WorldWideScience

Sample records for acidizing system matrix

  1. A novel enzyme-based acidizing system: Matrix acidizing and drilling fluid damage removal

    Energy Technology Data Exchange (ETDEWEB)

    Harris, R.E.; McKay, D.M. [Cleansorb Limited, Surrey (United Kingdom); Moses, V. [King`s College, London (United Kingdom)

    1995-12-31

    A novel acidizing process is used to increase the permeability of carbonate rock cores in the laboratory and to remove drilling fluid damage from cores and wafers. Field results show the benefits of the technology as applied both to injector and producer wells.

  2. Matrix fractional systems

    Science.gov (United States)

    Tenreiro Machado, J. A.

    2015-08-01

    This paper addresses the matrix representation of dynamical systems in the perspective of fractional calculus. Fractional elements and fractional systems are interpreted under the light of the classical Cole-Cole, Davidson-Cole, and Havriliak-Negami heuristic models. Numerical simulations for an electrical circuit enlighten the results for matrix based models and high fractional orders. The conclusions clarify the distinction between fractional elements and fractional systems.

  3. Event matrix system

    International Nuclear Information System (INIS)

    The number of background events in nuclear and particle physics experiments which use multiwire proportional chambers can be extremely high. Using a computer to resolve these events results in a high deadtime for the experiment. A fast matrix system for decreasing the number of background events is described in this report. 4 figures

  4. Fragmentation of extracellular matrix by hypochlorous acid

    DEFF Research Database (Denmark)

    Woods, Alan A; Davies, Michael Jonathan

    2003-01-01

    of the MPO-derived oxidant hypochlorous acid (HOCl) with extracellular matrix from vascular smooth muscle cells and healthy pig arteries has been examined. HOCl is rapidly consumed by such matrix samples, with the formation of matrix-derived chloramines or chloramides. The yield of these intermediates...... increases with HOCl dose. These materials undergo a time- and temperature-dependent decay, which parallels the release of sugar and protein components from the treated matrix, consistent with these species being important intermediates. Matrix damage is enhanced by species that increase chloramine...

  5. Oil-free hyaluronic acid matrix for serial femtosecond crystallography

    Science.gov (United States)

    Sugahara, Michihiro; Song, Changyong; Suzuki, Mamoru; Masuda, Tetsuya; Inoue, Shigeyuki; Nakane, Takanori; Yumoto, Fumiaki; Nango, Eriko; Tanaka, Rie; Tono, Kensuke; Joti, Yasumasa; Kameshima, Takashi; Hatsui, Takaki; Yabashi, Makina; Nureki, Osamu; Numata, Keiji; Iwata, So

    2016-04-01

    The grease matrix was originally introduced as a microcrystal-carrier for serial femtosecond crystallography and has been expanded to applications for various types of proteins, including membrane proteins. However, the grease-based matrix has limited application for oil-sensitive proteins. Here we introduce a grease-free, water-based hyaluronic acid matrix. Applications for proteinase K and lysozyme proteins were able to produce electron density maps at 2.3-Å resolution.

  6. Matrix member for containing fuel cell acid electrolyte

    International Nuclear Information System (INIS)

    A matrix member for carrying the acid electrolyte of a fuel cell comprised of a first layer containing a carbon material and a second layer containing a silicon carbide material. A further matrix member is disclosed wherein the mean pore size of the member is substantially equal to or less than that mean pore size of at least one of the fuel cell electrodes

  7. Analysis of amino acids network based on distance matrix

    Science.gov (United States)

    Ali, Tazid; Akhtar, Adil; Gohain, Nisha

    2016-06-01

    In this paper we have constructed a distance matrix of the amino acids. The distance is defined based on the relative evolutionary importance of the base position of the corresponding codons. From this distance matrix a network of the amino acids is obtained. We have argued that this network depicts the evolutionary pattern of the amino acids. To examine the relative importance of the amino acids with respect to this network we have discussed different measures of centrality. We have also investigated the correlation coefficients between different measures of centrality. Further we have explored clustering coefficient as well as degree of distribution.

  8. Controllability of semilinear matrix Lyapunov systems

    OpenAIRE

    Bhaskar Dubey; Raju K. George

    2013-01-01

    In this article, we establish some sufficient conditions for the complete controllability of semilinear matrix Lyapunov systems involving Lipschitzian and non-Lipschitzian nonlinearities. In case of non-Lipschitzian nonlinearities, we assume that nonlinearities are of monotone type.

  9. Systematic Exploration of an Efficient Amino Acid Substitution Matrix: MIQS.

    Science.gov (United States)

    Tomii, Kentaro; Yamada, Kazunori

    2016-01-01

    Amino acid sequence comparisons to find similarities between proteins are fundamental sequence information analyses for inferring protein structure and function. In this study, we improve amino acid substitution matrices to identify distantly related proteins. We systematically sampled and benchmarked substitution matrices generated from the principal component analysis (PCA) subspace based on a set of typical existing matrices. Based on the benchmark results, we identified a region of highly sensitive matrices in the PCA subspace using kernel density estimation (KDE). Using the PCA subspace, we were able to deduce a novel sensitive matrix, called MIQS, which shows better detection performance for detecting distantly related proteins than those of existing matrices. This approach to derive an efficient amino acid substitution matrix might influence many fields of protein sequence analysis. MIQS is available at http://csas.cbrc.jp/Ssearch/ . PMID:27115635

  10. The Matrix exponential, Dynamic Systems and Control

    DEFF Research Database (Denmark)

    Poulsen, Niels Kjølstad

    2004-01-01

    The matrix exponential can be found in various connections in analysis and control of dynamic systems. In this short note we are going to list a few examples. The matrix exponential usably pops up in connection to the sampling process, whatever it is in a deterministic or a stochastic setting or it...... is a tool for determining a Gramian matrix. This note is intended to be used in connection to the teaching post the course in Stochastic Adaptive Control (02421) given at Informatics and Mathematical Modelling (IMM), The Technical University of Denmark. This work is a result of a study of the...

  11. Anacardic Acid Inhibits the Catalytic Activity of Matrix Metalloproteinase-2 and Matrix Metalloproteinase-9

    OpenAIRE

    Omanakuttan, Athira; Nambiar, Jyotsna; Harris, Rodney M.; Bose, Chinchu; Pandurangan, Nanjan; Varghese, Rebu K.; Kumar, Geetha B.; Tainer, John A; Banerji, Asoke; Perry, J. Jefferson P.; Nair, Bipin G

    2012-01-01

    Cashew nut shell liquid (CNSL) has been used in traditional medicine for the treatment of a wide variety of pathophysiological conditions. To further define the mechanism of CNSL action, we investigated the effect of cashew nut shell extract (CNSE) on two matrix metalloproteinases, MMP-2/gelatinase A and MMP-9/gelatinase B, which are known to have critical roles in several disease states. We observed that the major constituent of CNSE, anacardic acid, markedly inhibited the gelatinase activit...

  12. GLYCOLIC-FORMIC ACID FLOWSHEET SLUDGE MATRIX STUDY

    Energy Technology Data Exchange (ETDEWEB)

    Lambert, D.; Koopman, D.

    2011-06-30

    Testing was completed to demonstrate the viability of the newly developed glycolic acid/formic acid flowsheet on processing in the Defense Waste Processing Facility's (DWPF) Chemical Process Cell (CPC). The Savannah River National Laboratory (SRNL) initiated a sludge matrix study to evaluate the impact of changing insoluble solid composition on the processing characteristics of slurries in DWPF. Four sludge simulants were prepared to cover two compositional ranges in the waste. The first was high iron/low aluminum versus low iron/high aluminum (referred to as HiFe or LoFe in this report). The second was high calcium-manganese/low nickel, chromium, and magnesium versus low calcium-manganese/high nickel, chromium, and magnesium (referred to as HiMn or LoMn in this report). These two options can be combined to form four distinct sludge compositions. The sludge matrix study called for testing each of these four simulants near the minimum acid required for nitrite destruction (100% acid stoichiometry) and at a second acid level that produced significant hydrogen by noble metal catalyzed decomposition of formic acid (150% acid stoichiometry). Four simulants were prepared based on the four possible combinations of the Al/Fe and Mn-Ca/Mg-Ni-Cr options. Preliminary simulant preparation work has already been documented. The four simulants were used for high and low acid testing. Eight planned experiments (GF26 to GF33) were completed to demonstrate the viability of the glycolic-formic flowsheet. Composition and physical property measurements were made on the SRAT product. Composition measurements were made on the condensate from the Mercury Water Wash Tank (MWWT), Formic Acid Vent Condenser (FAVC), ammonia scrubber and on SRAT samples pulled throughout the SRAT cycle. Updated values for formate loss and nitrite-tonitrate conversion were found that can be used in the acid calculations for future sludge matrix process simulations with the glycolic acid/formic acid

  13. Anacardic acid inhibits the catalytic activity of matrix metalloproteinase-2 and matrix metalloproteinase-9.

    Science.gov (United States)

    Omanakuttan, Athira; Nambiar, Jyotsna; Harris, Rodney M; Bose, Chinchu; Pandurangan, Nanjan; Varghese, Rebu K; Kumar, Geetha B; Tainer, John A; Banerji, Asoke; Perry, J Jefferson P; Nair, Bipin G

    2012-10-01

    Cashew nut shell liquid (CNSL) has been used in traditional medicine for the treatment of a wide variety of pathophysiological conditions. To further define the mechanism of CNSL action, we investigated the effect of cashew nut shell extract (CNSE) on two matrix metalloproteinases, MMP-2/gelatinase A and MMP-9/gelatinase B, which are known to have critical roles in several disease states. We observed that the major constituent of CNSE, anacardic acid, markedly inhibited the gelatinase activity of 3T3-L1 cells. Our gelatin zymography studies on these two secreted gelatinases, present in the conditioned media from 3T3-L1 cells, established that anacardic acid directly inhibited the catalytic activities of both MMP-2 and MMP-9. Our docking studies suggested that anacardic acid binds into the MMP-2/9 active site, with the carboxylate group of anacardic acid chelating the catalytic zinc ion and forming a hydrogen bond to a key catalytic glutamate side chain and the C15 aliphatic group being accommodated within the relatively large S1' pocket of these gelatinases. In agreement with the docking results, our fluorescence-based studies on the recombinant MMP-2 catalytic core domain demonstrated that anacardic acid directly inhibits substrate peptide cleavage in a dose-dependent manner, with an IC₅₀ of 11.11 μM. In addition, our gelatinase zymography and fluorescence data confirmed that the cardol-cardanol mixture, salicylic acid, and aspirin, all of which lack key functional groups present in anacardic acid, are much weaker MMP-2/MMP-9 inhibitors. Our results provide the first evidence for inhibition of gelatinase catalytic activity by anacardic acid, providing a novel template for drug discovery and a molecular mechanism potentially involved in CNSL therapeutic action. PMID:22745359

  14. Electromagnetic Compatibility of Matrix Converter System

    Directory of Open Access Journals (Sweden)

    S. Fligl

    2006-12-01

    Full Text Available The presented paper deals with matrix converters pulse width modulation strategies design with emphasis on the electromagnetic compatibility. Matrix converters provide an all-silicon solution to the problem of converting AC power from one frequency to another, offering almost all the features required of an ideal static frequency changer. They possess many advantages compared to the conventional voltage or current source inverters. A matrix converter does not require energy storage components as a bulky capacitor or an inductance in the DC-link, and enables the bi-directional power flow between the power supply and load. The most of the contemporary modulation strategies are able to provide practically sinusoidal waveforms of the input and output currents with negligible low order harmonics, and to control the input displacement factor. The perspective of matrix converters regarding EMC in comparison with other types of converters is brightly evident because it is no need to use any equipment for power factor correction and current and voltage harmonics reduction. Such converter with proper control is properly compatible both with the supply mains and with the supplied load. A special digital control system was developed for the realized experimental test bed which makes it possible to achieve greater throughput of the digital control system and its variability.

  15. Generating Nice Linear Systems for Matrix Gaussian Elimination

    Science.gov (United States)

    Homewood, L. James

    2004-01-01

    In this article an augmented matrix that represents a system of linear equations is called nice if a sequence of elementary row operations that reduces the matrix to row-echelon form, through matrix Gaussian elimination, does so by restricting all entries to integers in every step. Many instructors wish to use the example of matrix Gaussian…

  16. Boost matrix converters in clean energy systems

    Science.gov (United States)

    Karaman, Ekrem

    This dissertation describes an investigation of novel power electronic converters, based on the ultra-sparse matrix topology and characterized by the minimum number of semiconductor switches. The Z-source, Quasi Z-source, Series Z-source and Switched-inductor Z-source networks were originally proposed for boosting the output voltage of power electronic inverters. These ideas were extended here on three-phase to three-phase and three-phase to single-phase indirect matrix converters. For the three-phase to three-phase matrix converters, the Z-source networks are placed between the three-switch input rectifier stage and the output six-switch inverter stage. A brief shoot-through state produces the voltage boost. An optimal pulse width modulation technique was developed to achieve high boosting capability and minimum switching losses in the converter. For the three-phase to single-phase matrix converters, those networks are placed similarly. For control purposes, a new modulation technique has been developed. As an example application, the proposed converters constitute a viable alternative to the existing solutions in residential wind-energy systems, where a low-voltage variable-speed generator feeds power to the higher-voltage fixed-frequency grid. Comprehensive analytical derivations and simulation results were carried out to investigate the operation of the proposed converters. Performance of the proposed converters was then compared between each other as well as with conventional converters. The operation of the converters was experimentally validated using a laboratory prototype.

  17. Matrix models with Penner interaction inspired by interacting ribonucleic acid

    Indian Academy of Sciences (India)

    Pradeep Bhadola; N Deo

    2015-02-01

    The Penner interaction known in studies of moduli space of punctured Riemann surfaces is introduced and studied in the context of random matrix model of homo RNA. An analytic derivation of the generating function is given and the corresponding partition function is derived numerically. An additional dependence of the structure combinatorics factor on (related to the size of the matrix and the interaction strength) is obtained. This factor has a strong effect on the structure combinatorics in the low regime. Databases are scanned for real ribonucleic acid (RNA) structures and pairing information for these RNA structures is computationally extracted. Then the genus is calculated for every structure and plotted as a function of length. The genus distribution function is compared with the prediction from the nonlinear (NL) model. The specific heat and distribution of structure with temperature calculated from the NL model shows that the NL inter-action is biased towards planar structures. The second derivative of specific heat changes phase from a double peaked function for small to a single peak for large . Detailed analysis reveals the presence of the double peak only for genus 0 structures, the higher genii behave normally with . Comparable behaviour is found in studies involving interactions of RNA with osmolytes and monovalent cations in unfolding experiments.

  18. Entanglement property in matrix product spin systems

    Institute of Scientific and Technical Information of China (English)

    ZHU Jing-Min

    2012-01-01

    We study the entanglement property in matrix product spin-ring systems systemically by von Neumann entropy.We find that:(i) the Hilbert space dimension of one spin determines the upper limit of the maximal value of the entanglement entropy of one spin,while for multiparticle entanglement entropy,the upper limit of the maximal value depends on the dimension of the representation matrices.Based on the theory,we can realize the maximum of the entanglement entropy of any spin block by choosing the appropriate control parameter values.(ii) When the entanglement entropy of one spin takes its maximal value,the entanglement entropy of an asymptotically large spin block,i.e. the renormalization group fixed point,is not likely to take its maximal value,and so only the entanglement entropy Sn of a spin block that varies with size n can fully characterize the spin-ring entanglement feature.Finally,we give the entanglement dynamics,i.e.the Hamiltonian of the matrix product system.

  19. Digraph matrix analysis applications to systems interactions

    Energy Technology Data Exchange (ETDEWEB)

    Alesso, H.P.; Altenbach, T.; Lappa, D.; Kimura, C.; Sacks, I.J.; Ashmore, B.C.; Fromme, D.; Smith, C.F.; Williams, W.

    1984-01-01

    Complex events such as Three Mile Island-2, Brown's Ferry-3 and Crystal River-3 have demonstrated that previously unidentified system interdependencies can be important to safety. A major aspect of these events was dependent faults (common cause/mode failures). The term systems interactions has been introduced by the Nuclear Regulatory Commission (NRC) to identify the concepts of spatial and functional coupling of systems which can lead to system interdependencies. Spatial coupling refers to dependencies resulting from a shared environmental condition; functional coupling refers to both dependencies resulting from components shared between safety and/or support systems, and to dependencies involving human actions. The NRC is currently developing guidelines to search for and evaluate adverse systems interactions at light water reactors. One approach utilizes graph theoretical methods and is called digraph matrix analysis (DMA). This methodology has been specifically tuned to the systems interaction problem. The objective of this paper is to present results from two DMA applications and to contrast them with the results from more traditional fault tree approaches.

  20. Higher pH acid stimulation systems

    Energy Technology Data Exchange (ETDEWEB)

    Abrams, A.; Richardson, E.A.; Scheuerman, R.F.; Templeton, C.C.

    1979-01-01

    Two types of high pH (4 to 6), mild acting acidizing systems developed for in-depth rock matrix stimulation for both sandstone and carbonate reservoirs are described. With these systems, in-depth stimulation capability is available from ambient to about 280 F (138 C). Buffer regulated (BR) systems also have application for near well-bore stimulation at temperatures of up to at least 365 F (185 C). The self-generating systems based on methyl formate (MF), the ammonium salt of monochloroacetic acid (CA), and methyl acetate (MA), have sandstone application ranges and are described. Three BR systems have been developed, based on formic, acetic, and citric acids. Included in the study is a brief review of the theory involved, experimental techniques for measuring acid reaction rates, and discussions of clay dissolution and carbonate acidization mechanisms. 16 references.

  1. Poly(lactic-co-glycolic acid) matrix incorporated with nisin as a novel antimicrobial biomaterial.

    Science.gov (United States)

    Correia, Rafaela Coelho; Jozala, Angela Faustino; Martins, Kelly Fernanda; Penna, Thereza Christina Vessoni; Duek, Eliana Aparecida de Rezende; Rangel-Yagui, Carlota de Oliveira; Lopes, André Moreni

    2015-04-01

    The use of poly(lactic-co-glycolic acid) (PLGA) matrix as a biomolecule carrier has been receiving great attention due to its potential therapeutic application. In this context, we investigated the PLGA matrix capacity to incorporate nisin, an antimicrobial peptide capable of inhibiting the growth of Gram-positive bacteria and bacterial spores germination. Nisin-incorporated PLGA matrices were evaluated based on the inhibitory effect against the nisin-bioindicator Lactobacillus sakei. Additionally, the PLGA-nisin matrix stability over an 8-months period was investigated, as well as the nisin release profile. For the incorporation conditions, we observed that a 5 h incorporation time, at 30 °C, with 250 μg/mL nisin solution in PBS buffer pH 4.5, resulted in the highest inhibitory activity of 2.70 logAU/mL. The PLGA-nisin matrix was found to be relatively stable and showed sustained drug delivery, with continuous release of nisin for 2 weeks. Therefore, PLGA-nisin matrix is could be used as a novel antimicrobial delivery system and an alternative to antibiotics incorporated into PLGA matrices.

  2. Symmetries of the 2D magnetic particle imaging system matrix

    International Nuclear Information System (INIS)

    In magnetic particle imaging (MPI), the relation between the particle distribution and the measurement signal can be described by a linear system of equations. For 1D imaging, it can be shown that the system matrix can be expressed as a product of a convolution matrix and a Chebyshev transformation matrix. For multidimensional imaging, the structure of the MPI system matrix is not yet fully explored as the sampling trajectory complicates the physical model. It has been experimentally found that the MPI system matrix rows have symmetries and look similar to the tensor products of Chebyshev polynomials. In this work we will mathematically prove that the 2D MPI system matrix has symmetries that can be used for matrix compression. (paper)

  3. Random matrix description of decaying quantum systems

    International Nuclear Information System (INIS)

    This paper describes a statistical model for decaying quantum systems (e.g. photo-dissociation or -ionization). It takes the interference between direct and indirect decay processes explicitly into account. The resulting expressions for the partial decay amplitudes and the corresponding cross sections may be considered a many-channel many-resonance generalization of Fano's original work on resonance lineshapes (Fano 1961 Phys. Rev. 124 1866). A statistical (random matrix) model is then introduced. It allows to describe chaotic scattering systems with tunable couplings to the decay channels. We focus on the autocorrelation function of the total (photo) cross section, and we find that it depends on the same combination of parameters, as the Fano-parameter distribution. These combinations are statistical variants of the one-channel Fano parameter. It is thus possible to study the Fano interference (i.e. the interference between direct and indirect decay paths) on the basis of the autocorrelation function, and thereby in the regime of overlapping resonances. It allows us to study the Fano interference in the limit of strongly overlapping resonances, where we find a persisting effect on the level of the weak localization correction

  4. Thermal transport in a coupled sinusoidal fracture-matrix system

    OpenAIRE

    N.Natarajan,; Suresh Kumar, G.

    2010-01-01

    In this study, the behavior of thermal fronts along the fracture is studied in a coupled fracture-matrix system with sinusoidal fracture geometry. Cold water is injected into the fracture, which advances gradually extracting heat from the adjacent reservoir matrix. The heat conduction into the rock-matrix is assumed to be one dimensionalperpendicular to the rock fracture. Constant temperature water is injected into the fracture and the behavior of thermal fronts for various thermal conductivi...

  5. Rapid HPLC analysis of amino acids and biogenic amines in wines during fermentation and evaluation of matrix effect.

    Science.gov (United States)

    Wang, Ya-Qin; Ye, Dong-Qing; Zhu, Bao-Qing; Wu, Guang-Feng; Duan, Chang-Qing

    2014-11-15

    A rapid HPLC method has been developed for the simultaneous determination of 23 amino acids, 10 biogenic amines and the ammonium ion in wine. Samples were pre-column derivatised with diethyl ethoxymethylenemalonate and separated using reversed-phase HPLC within 30 min. The matrix effect was evaluated when measuring samples taken from different stages of fermentation. Most compounds showed no obvious matrix effect, whereas proline, ethanolamine and spermine had remarkably different responses to variable concentrations of sugar. High concentrations of sugar affected the pH of the derivatisation reaction system; proline, ethanolamine and spermine derivatives were sensitive to this effect. Matrix-matched calibration was used for the quantification of these compounds. Validation of the method showed that it was accurate, reproducible and efficient for the simultaneous determination of amino acids and biogenic amines in wines during fermentation. As a specific application of the method, red wine samples taken from different stages of fermentation were analysed. PMID:24912689

  6. Application of transmissibility matrix and random matrix to Bayesian system identification with response measurements only

    Science.gov (United States)

    Yan, Wang-Ji; Katafygiotis, Lambros S.

    2016-10-01

    The problem of stochastic system identification utilizing response measurements only is considered in this paper. A negative log-likelihood function utilized to determine the posterior most probable parameters and their associated uncertainties is formulated by incorporating transmissibility matrix concept, random matrix theory and Bayes’ theorem. A numerically iterative coupled method involving the optimization of the parameters in groups is proposed so as to reduce the dimension of the numerical optimization problem involved. The initial guess for the parameters to be optimized is also properly estimated through asymptotic analysis. One novel feature of the proposed method is to avoid repeated time-consuming evaluation of the determinant and inverse of the covariance matrix during optimization due to exploring the statistical properties of the trace of Wishart matrix. The proposed method requires no information about the model of the external input. The theory described in this work is illustrated with synthetic data and field data measured from a laboratory model installed with wireless sensors.

  7. Amino Acids Analysis by MALDI Mass Spectrometry Using Carbon Nanotube as Matrix

    Institute of Scientific and Technical Information of China (English)

    张菁; 王昊阳; 郭寅龙

    2005-01-01

    Twenty common amino acids have been analyzed successfully by matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) using carbon nanotubes as matrix. From the spectra, little or no background interference or fragmentation of the analytes has been observed. This method was also applied to the analysis of amino acid mixture successfully. Carbon nanotubes have some features such as large surface area to disperse the analyte molecules sufficiently and prevent the sample aggregation and strong ultraviolet absorption to transfer energy easily to the analyte molecules. The present method has potential application for the rapid and sensitive analysis of amino acids and their mixture.

  8. 37% Phosphoric Acid Induced Stronger Matrix Metalloproteinase-8 Expression of the Dental Pulp than 19% Ethylene Diamine Tetraacetic Acid

    Directory of Open Access Journals (Sweden)

    Nadie Fatimatuzzahro

    2014-11-01

    Full Text Available Etching agents such as ethylene diamine tetraacetic acid (EDTA and phosphoric acid which are widely used in adhesive restoration system aimed to increase for retention of restorative materials, may act a chemical irritant that induce inflammation of dental pulp. Inflammation is a body response against irritant and infectious agents. Matrix metalloproteinase-8, the major collagenolytic enzyme, degrades collagen type 1. This enzyme is expressed in low level in normal condition, however, the expression will increase during inflammation. The purpose of the present research was to study the effect of 19% EDTA and 37% phosphoric acid application as an etching agents on the MMP-8 expression of dental pulp. Forty-five male Sprague Dawley rats were divided into 3 groups. Cavity preparation was made on the occlusal surface of maxillary first molar using a round diamond bur. 19% EDTA, 37% phosphoric acid, and distilled water were applied on the surface of the cavity of the teeth in group I, II, and III subsequently. The cavity then filed by glass ionomer cements. The rats were sacrified at 1, 3, 5, 7, and 14 days after the treatment (n=3 for each day. The specimens were then processed histologically. Immunohistochemical (IHC analysis was performed using rabbit anti rat MMP-8 polyclonal antibody to examine MMP-8 expression and HE (Hematoxylen Eosin staining to observe the number of macrophages. The results showed 37% phosphoric acid application induced stronger expression of MMP-8 and higher number of macrophages than 19% EDTA. The strongest expression of MMP-8 seems on 5 days after the treatment where the highest number of macrophages were also found.

  9. Percolation phenomena in diffusion-controlled polymer matrix systems

    Institute of Scientific and Technical Information of China (English)

    徐铜文; 何炳林

    1997-01-01

    The controlled release of two kinds of drugs,5-fluorouracil (5-FU) and hydrocortisonum (Hydro.) loaded in poly(ethylene-vinylalcohol) (EVAL) was dealt with,of which 5-FU/EVAL and Hydro /EVAL matrix systems are composed.The results were analyzed using the pseudo-steady-diffusion models coupled with the fundamental concepts of percolation theory.The percolation thresholds for the two systems were calculated,which could indicate the contributions of pore diffusion and matrix diffusion.

  10. Content-boosted Matrix Factorization Techniques for Recommender Systems

    OpenAIRE

    Nguyen, Jennifer; Zhu, Mu

    2012-01-01

    Many businesses are using recommender systems for marketing outreach. Recommendation algorithms can be either based on content or driven by collaborative filtering. We study different ways to incorporate content information directly into the matrix factorization approach of collaborative filtering. These content-boosted matrix factorization algorithms not only improve recommendation accuracy, but also provide useful insights about the contents, as well as make recommendations more easily inte...

  11. Density matrix embedding theory for interacting electron-phonon systems

    Science.gov (United States)

    Sandhoefer, Barbara; Chan, Garnet Kin-Lic

    2016-08-01

    We describe the extension of the density matrix embedding theory framework to coupled interacting fermion-boson systems. This provides a frequency-independent, entanglement embedding formalism to treat bulk fermion-boson problems. We illustrate the concepts within the context of the one-dimensional Hubbard-Holstein model, where the phonon bath states are obtained from the Schmidt decomposition of a self-consistently adjusted coherent state. We benchmark our results against accurate density matrix renormalization group calculations.

  12. 3-Aminoquinoline/p-coumaric acid as a MALDI matrix for glycopeptides, carbohydrates, and phosphopeptides.

    Science.gov (United States)

    Fukuyama, Yuko; Funakoshi, Natsumi; Takeyama, Kohei; Hioki, Yusaku; Nishikaze, Takashi; Kaneshiro, Kaoru; Kawabata, Shin-Ichirou; Iwamoto, Shinichi; Tanaka, Koichi

    2014-02-18

    Glycosylation and phosphorylation are important post-translational modifications in biological processes and biomarker research. The difficulty in analyzing these modifications is mainly their low abundance and dissociation of labile regions such as sialic acids or phosphate groups. One solution in matrix-assisted laser desorption/ionization (MALDI) mass spectrometry is to improve matrices for glycopeptides, carbohydrates, and phosphopeptides by increasing the sensitivity and suppressing dissociation of the labile regions. Recently, a liquid matrix 3-aminoquinoline (3-AQ)/α-cyano-4-hydroxycinnamic acid (CHCA) (3-AQ/CHCA), introduced by Kolli et al. in 1996, has been reported to increase sensitivity for carbohydrates or phosphopeptides, but it has not been systematically evaluated for glycopeptides. In addition, 3-AQ/CHCA enhances the dissociation of labile regions. In contrast, a liquid matrix 1,1,3,3-tetramethylguanidium (TMG, G) salt of p-coumaric acid (CA) (G3CA) was reported to suppress dissociation of sulfate groups or sialic acids of carbohydrates. Here we introduce a liquid matrix 3-AQ/CA for glycopeptides, carbohydrates, and phosphopeptides. All of the analytes were detected as [M + H](+) or [M - H](-) with higher or comparable sensitivity using 3-AQ/CA compared with 3-AQ/CHCA or 2,5-dihydroxybenzoic acid (2,5-DHB). The sensitivity was increased 1- to 1000-fold using 3-AQ/CA. The dissociation of labile regions such as sialic acids or phosphate groups and the fragmentation of neutral carbohydrates were suppressed more using 3-AQ/CA than using 3-AQ/CHCA or 2,5-DHB. 3-AQ/CA was thus determined to be an effective MALDI matrix for high sensitivity and the suppression of dissociation of labile regions in glycosylation and phosphorylation analyses.

  13. Higher-pH acid stimulation systems

    Energy Technology Data Exchange (ETDEWEB)

    Abrams, A.; Richardson, E.A.; Scheuerman, R.F.; Templeton, C.C.

    1983-12-01

    Two types of high-pH (4 to 6), mild-acting acidizing systems have been developed for in-depth rock matrix stimulation of both sandstone and carbonate reservoirs: (1) self-generating (SG), which utilizes the hydrolysis of an ester (or other acid producers) to generate low concentrations of H/sup +/, and (2) buffer-regulated (BR), which utilizes an organic acid buffered with its ammonium salt. For sandstone stimulations, the HF acid generation is provided by the addition of ammonium fluoride. In-depth stimulation can be achieved with these systems from ambient temperature to about 280/sup 0/F (138/sup 0/C). Near-wellbore damage removal can be obtained by using BR systems to at least 380/sup 0/F (193/sup 0/C). Maximum application temperature is being determined now. Three SG systems have been developed for different operating temperature ranges: methyl formate (MF), for 130 to 180/sup 0/F (54 to 82/sup 0/C); the ammonium salt of monochloroacetic acid (CA), for 180 to 215/sup 0/F (82 to 102/sup 0/C); and methyl acetate (MA), for 190 to 280/sup 0/F (88 to 130/sup 0/C). Similarly, BR systems have been developed for different pH ranges: formic acid (F) for pH 3.5 to 4.0, and acetic acid (A) and citric acid (C) for pH 4.5 to 5.0. Because of their moderate pH levels and low corrosiveness, BR systems also have potential application at temperatures where excessive corrosion precludes the use of conventional acids. Laboratory corrosion studies on BR systems show that corrosion rates, without inhibitors, are within acceptable limits to about 380/sup 0/F (193/sup 0/C). Corrosion inhibitors should allow applicability to higher temperatures. This paper reviews the theory and experiments used in the development of these SG and BR systems. Field test results with these systems are presented in Refs. 1 through 4.

  14. Linear $r$-matrix algebra for classical separable systems

    CERN Document Server

    Eilbeck, J C; Kuznetsov, V B; Tsiganov, A V; Kuznetsov, Vadim B.

    1994-01-01

    We consider a hierarchy of the natural type Hamiltonian systems of $n$ degrees of freedom with polynomial potentials separable in general ellipsoidal and general paraboloidal coordinates. We give a Lax representation in terms of $2\\times 2$ matrices for the whole hierarchy and construct the associated linear $r$-matrix algebra with the $r$-matrix dependent on the dynamical variables. A Yang-Baxter equation of dynamical type is proposed. Using the method of variable separation we provide the integration of the systems in classical mechanics conctructing the separation equations and, hence, the explicit form of action variables. The quantisation problem is discussed with the help of the separation variables.

  15. Matrix solid-phase dispersion for the liquid chromatographic determination of phenolic acids in Melissa officinalis.

    Science.gov (United States)

    Ziaková, Alica; Brandsteterová, Eva; Blahová, Eva

    2003-01-01

    Matrix solid-phase dispersion (MSPD) was used for sample preparation of plant material (Melissa officinalis, Lemon Balm) prior to liquid chromatography of rosmarinic, caffeic and protocatechuic acids, phenolic compounds present in this herb. Different MSPD sorbents and various elution agents were tested and the optimal extraction conditions determined with the aim to obtain extraction recoveries greater than 90% for all analytes. PMID:12568390

  16. Sparse matrix approximation method for an active optical control system

    Science.gov (United States)

    Murphy, Timothy P.; Lyon, Richard G.; Dorband, John E.; Hollis, Jan M.

    2001-12-01

    We develop a sparse matrix approximation method to decompose a wave front into a basis set of actuator influence functions for an active optical system consisting of a deformable mirror and a segmented primary mirror. The wave front used is constructed by Zernike polynomials to simulate the output of a phase-retrieval algorithm. Results of a Monte Carlo simulation of the optical control loop are compared with the standard, nonsparse approach in terms of accuracy and precision, as well as computational speed and memory. The sparse matrix approximation method can yield more than a 50-fold increase in the speed and a 20-fold-reduction in matrix size and a commensurate decrease in required memory, with less than 10% degradation in solution accuracy. Our method is also shown to be better than when elements are selected for the sparse matrix on a magnitude basis alone. We show that the method developed is a viable alternative to use of the full control matrix in a phase-retrieval-based active optical control system.

  17. Phosphoric acid as a matrix additive for MALDI MS analysis of phosphopeptides and phosphoproteins

    DEFF Research Database (Denmark)

    Kjellström, Sven; Jensen, Ole Nørregaard

    2004-01-01

    Phosphopeptides are often detected with low efficiency by MALDI MS analysis of peptide mixtures. In an effort to improve the phosphopeptide ion response in MALDI MS, we investigated the effects of adding low concentrations of organic and inorganic acids during peptide sample preparation in 2...... acid to 2,5-DHB were also observed in LC-MALDI-MS analysis of tryptic phosphopeptides of B. subtilis PrkC phosphoprotein. Finally, the mass resolution of MALDI mass spectra of intact proteins was significantly improved by using phosphoric acid in 2,5-DHB matrix....

  18. Quantum phase transitions about parity breaking in matrix product systems

    Institute of Scientific and Technical Information of China (English)

    ZHU Jing-Min

    2011-01-01

    According to our scheme to construct quantum phase transitions (QPTs) in spin chain systems with matrix product ground states, we first successfully combine matrix product state (MPS) QPTs with spontaneous symmetry breaking. For a concrete model, we take into account a kind of MPS QPTs accompanied by spontaneous parity breaking, though for either side of the critical point the GS is typically unique, and show that the kind of MPS QPTs occur only in the thermodynamic limit and are accompanied by the appearance of singularities, diverging correlation length, vanishing energy gap and the entanglement entropy of a half-infinite chain not only staying finite but also whose first derivative discontinuous.

  19. Constrained Solutions of a System of Matrix Equations

    Directory of Open Access Journals (Sweden)

    Qing-Wen Wang

    2012-01-01

    Full Text Available We derive the necessary and sufficient conditions of and the expressions for the orthogonal solutions, the symmetric orthogonal solutions, and the skew-symmetric orthogonal solutions of the system of matrix equations AX=B and XC=D, respectively. When the matrix equations are not consistent, the least squares symmetric orthogonal solutions and the least squares skew-symmetric orthogonal solutions are respectively given. As an auxiliary, an algorithm is provided to compute the least squares symmetric orthogonal solutions, and meanwhile an example is presented to show that it is reasonable.

  20. Optimization of MIMO Systems Capacity Using Large Random Matrix Methods

    Directory of Open Access Journals (Sweden)

    Philippe Loubaton

    2012-11-01

    Full Text Available This paper provides a comprehensive introduction of large random matrix methods for input covariance matrix optimization of mutual information of MIMO systems. It is first recalled informally how large system approximations of mutual information can be derived. Then, the optimization of the approximations is discussed, and important methodological points that are not necessarily covered by the existing literature are addressed, including the strict concavity of the approximation, the structure of the argument of its maximum, the accuracy of the large system approach with regard to the number of antennas, or the justification of iterative water-filling optimization algorithms. While the existing papers have developed methods adapted to a specific model, this contribution tries to provide a unified view of the large system approximation approach.

  1. Determination of oxytetracycline residues in matrixes from a freshwater recirculating aquaculture system.

    Science.gov (United States)

    Carson, Mary C; Bullock, Graham; Bebak-Williams, Julie

    2002-01-01

    This paper describes related procedures to determine the amount of oxytetracycline (OTC) present in trout tissue (muscle with skin attached), biofilter sand, sediment, and tank water from a recirculating aquaculture system. OTC was extracted from the matrixes by different techniques, depending on complexity of the matrix and desired OTC detection level in that matrix. Listed in order of increasing complexity, OTC was extracted from tank water by dilution with acidic buffer containing ethylenediaminetetraacetic acid (EDTA); from biofilter sand by shaking with 0.1 N HCl; from sediment by homogenization and shaking with buffer/EDTA; and from ground trout by homogenization and shaking with buffer/EDTA (twice), with further cleanup and concentration of the extract on a polymeric solid-phase extraction cartridge. The 4 procedures all used the same reversed-phase gradient chromatography on a polymeric column with UV detection at 350 nm. The lower limit of detection (estimated) and upper limit of validation for each of these 4 matrixes were 0.04-4.0 microg/g (ppm; trout), 0.03-20 ppm (biofilter sand), 1-6000 ppm (sediment), and 0.003-10 ppm (water). Recoveries ranged from 82 to 108%, with relative standard deviation recirculating aquaculture system. PMID:11990017

  2. Simulating quantum systems on classical computers with matrix product states

    Energy Technology Data Exchange (ETDEWEB)

    Kleine, Adrian

    2010-11-08

    In this thesis, the numerical simulation of strongly-interacting many-body quantum-mechanical systems using matrix product states (MPS) is considered. Matrix-Product-States are a novel representation of arbitrary quantum many-body states. Using quantum information theory, it is possible to show that Matrix-Product-States provide a polynomial-sized representation of one-dimensional quantum systems, thus allowing an efficient simulation of one-dimensional quantum system on classical computers. Matrix-Product-States form the conceptual framework of the density-matrix renormalization group (DMRG). After a general introduction in the first chapter of this thesis, the second chapter deals with Matrix-Product-States, focusing on the development of fast and stable algorithms. To obtain algorithms to efficiently calculate ground states, the density-matrix renormalization group is reformulated using the Matrix-Product-States framework. Further, time-dependent problems are considered. Two different algorithms are presented, one based on a Trotter decomposition of the time-evolution operator, the other one on Krylov subspaces. Finally, the evaluation of dynamical spectral functions is discussed, and a correction vector-based method is presented. In the following chapters, the methods presented in the second chapter, are applied to a number of different physical problems. The third chapter deals with the existence of chiral phases in isotropic one-dimensional quantum spin systems. A preceding analytical study based on a mean-field approach indicated the possible existence of those phases in an isotropic Heisenberg model with a frustrating zig-zag interaction and a magnetic field. In this thesis, the existence of the chiral phases is shown numerically by using Matrix-Product-States-based algorithms. In the fourth chapter, we propose an experiment using ultracold atomic gases in optical lattices, which allows a well controlled observation of the spin-charge separation (of

  3. MULTIAGENT SYSTEM BASED ON GENETIC ACCESS MATRIX ANALYSIS

    Directory of Open Access Journals (Sweden)

    Noto Masato

    2012-12-01

    Full Text Available How should an individual contribute to the public good? Conversely, how does the public help the individual? We should analyze and alleviate conflicts in community clouds. Covert channels in the access matrix are caused by conflicts between public values and a private sense of values. We cannot control the information leaks from the covert channels by using only access control. We believe that the community cloud system should emphasize harmony between public values and a private sense of values. We interpret the access matrix as follows: The acts of the individual are generalized and symbolized by an access matrix that describes the access operations of the subject. We propose a multiagent system embodying the concept of swarm intelligence to analyze the covert channels that arise. Each agent has a group target and an individual target. The group target and an individual target include targets for generation of access and restriction of access. The system does not have any principle of universal control. Instead, an agent’s interactions are guided by metaheuristics for achieving targets. The social order of the whole society is made from the agents’ interactions related to the group value target, group game target, an individual value target, and an individual game target. The conceptual framework and multiagent system presented here are intended to support people. If the covert channel problem can be solved, it will become possible for people to use community clouds safely.

  4. Correction of tear trough deformity with a cohesive polydensified matrix hyaluronic acid: a case series

    OpenAIRE

    Huber-Vorländer J; Kürten M

    2015-01-01

    Jürgen Huber-Vorländer, Martin KürtenFort Malakoff Klinik, Mainz, GermanyAbstract: The tear trough or infraorbital hollow is a challenging area to treat, and only a few fillers are suitable for this delicate area. We report on a European case series of six subjects with mild to severe tear troughs who received treatment with cohesive polydensified matrix (CPM®) technology hyaluronic acid gel (Belotero® Balance). The product was injected as small depo...

  5. Enzyme system comprising an enzyme bonded in a porous matrix

    Science.gov (United States)

    Ackerman, Eric [Richland, WA; Liu, Jun [West Richland, WA

    2010-12-07

    A protein system is described in which a protein is bound within a matrix material that has pores that are sized to achieve excellent properties such as: activity, protein density, and stability. In a preferred embodiment, the pore sizes range from 50 to 400 .ANG.. One protein that has demonstrated surprisingly good results in this system is OPH. This protein is known to degrade organophosphorus compounds such as are found in chemical weapons and pesticides. Novel methods of forming the protein system and methods of making OPH are also described.

  6. THE BONUS-MALUS SYSTEM MODELLING USING THE TRANSITION MATRIX

    Directory of Open Access Journals (Sweden)

    SANDRA TEODORESCU

    2012-05-01

    Full Text Available The motor insurance is an important branch of non-life insurance in many countries; in some of them, coming first in total premium income category (in Romania, for example. The Bonus-Malus system implementation is one of the solutions chosen by the insurance companies in order to increase the efficiency in the motor insurance domain. This system has been recently introduced by the Romanian insurers as well. In this paper I present the means for modelling the bonus-malus system using the transition matrix.

  7. Gossypol-cross-linked boronic acid-modified hydrogels: a functional matrix for the controlled release of an anticancer drug.

    Science.gov (United States)

    Heleg-Shabtai, Vered; Aizen, Ruth; Orbach, Ron; Aleman-Garcia, Miguel Angel; Willner, Itamar

    2015-02-24

    Anticancer drug gossypol cross-links phenylboronic acid-modified acrylamide copolymer chains to form a hydrogel matrix. The hydrogel is dissociated in an acidic environment (pH 4.5), and its dissociation is enhanced in the presence of lactic acid (an α-hydroxy carboxylic acid) as compared to formic acid. The enhanced dissociation of the hydrogel by lactic acid is attributed to the effective separation of the boronate ester bridging groups through the formation of a stabilized complex between the boronic acid substituent and the lactic acid. Because lactic acid exists in cancer cells in elevated amounts and the cancer cells' environment is acidic, the cross-linked hydrogel represents a stimuli-responsive matrix for the controlled release of gossypol. The functionality is demonstrated and characterized by rheology and other spectroscopic means. PMID:25664656

  8. The Effects of Omega-3 Fatty Acids on Matrix Metalloproteinase-9 Production and Cell Migration in Human Immune Cells: Implications for Multiple Sclerosis

    OpenAIRE

    Lynne Shinto; Gail Marracci; Lauren Bumgarner; Vijayshree Yadav

    2011-01-01

    In multiple sclerosis (MS), compromised blood-brain barrier (BBB) integrity contributes to inflammatory T cell migration into the central nervous system. Matrix metalloproteinase-9 (MMP-9) is associated with BBB disruption and subsequent T cell migration into the CNS. The aim of this paper was to evaluate the effects of omega-3 fatty acids on MMP-9 levels and T cell migration. Peripheral blood mononuclear cells (PBMC) from healthy controls were pretreated with two types of omega-3 fatty acids...

  9. On the employment of lambda carrageenan in a matrix system. III. Optimization of a lambda carrageenan-HPMC hydrophilic matrix

    NARCIS (Netherlands)

    Bonferoni, MC; Rossi, S; Ferrari, F; Bertoni, M; Bolhuis, GK; Caramella, C

    1998-01-01

    The lambda carrageenan/HPMC ratio in matrix tablets has been optimized in order to obtain pH-independent release profiles of chlorpheniramine maleate, a freely soluble drug. Release profiles in acidic (pH 1.2) and neutral (pH 6.8) media were fitted according to the Weibull and the power law models.

  10. Correction of tear trough deformity with a cohesive polydensified matrix hyaluronic acid: a case series

    Directory of Open Access Journals (Sweden)

    Huber-Vorländer J

    2015-06-01

    Full Text Available Jürgen Huber-Vorländer, Martin KürtenFort Malakoff Klinik, Mainz, GermanyAbstract: The tear trough or infraorbital hollow is a challenging area to treat, and only a few fillers are suitable for this delicate area. We report on a European case series of six subjects with mild to severe tear troughs who received treatment with cohesive polydensified matrix (CPM® technology hyaluronic acid gel (Belotero® Balance. The product was injected as small depots (up to ten small boli 0.2 mL maximum each per side at the supraperiosteal level along or below the orbital rim. Follow-up visits took place at 1, 3, 6, and 9 months after injection for independent evaluation of the clinical effect using the Merz Aesthetics Scale™ for infraorbital hollows and the Global Aesthetic Improvement Scale. Adverse events were also recorded. Mean hollowness scores were considerably improved compared with baseline in all subjects. In all women, the improvements remained throughout the 9-month study, with none reverting to their baseline score. Subjects’ satisfaction with treatment was very high throughout the study, and all women stated that they would repeat treatment with the same product. The CPM hyaluronic acid gel was well tolerated. CPM hyaluronic acid gel is a safe and effective treatment for the tear trough area.Keywords: Belotero® Balance, cohesive polydensified matrix (CPM®, hyaluronic acid, infraorbital hollow, tear trough

  11. Sparse matrix methods research using the CSM testbed software system

    Science.gov (United States)

    Chu, Eleanor; George, J. Alan

    1989-01-01

    Research is described on sparse matrix techniques for the Computational Structural Mechanics (CSM) Testbed. The primary objective was to compare the performance of state-of-the-art techniques for solving sparse systems with those that are currently available in the CSM Testbed. Thus, one of the first tasks was to become familiar with the structure of the testbed, and to install some or all of the SPARSPAK package in the testbed. A suite of subroutines to extract from the data base the relevant structural and numerical information about the matrix equations was written, and all the demonstration problems distributed with the testbed were successfully solved. These codes were documented, and performance studies comparing the SPARSPAK technology to the methods currently in the testbed were completed. In addition, some preliminary studies were done comparing some recently developed out-of-core techniques with the performance of the testbed processor INV.

  12. Decoherence in chaotic and integrable systems: a random matrix approach

    Science.gov (United States)

    Gorin, T.; Seligman, T. H.

    2003-03-01

    We study the influence of chaos and order on entanglement and decoherence. In view of applications in quantum computing and teleportation which should be able to work with arbitrarily complicated states, we pay particular attention to the behavior of random states. While studies with coherent states indicate that chaos accelerates decoherence and entanglement, we find that there is practically no difference between the chaotic and the integrable case, as far as random states are concerned. In the present studies we use unitary time evolution of the total system, and partial traces to emulate decoherence. Random matrix models are a natural choice to describe the dynamics of random states. The invariant aspects of chaos and order are then reflected in the different spectral statistics. We develop random matrix models for the evolution of entanglement for a large variety of situations, discussing the strong coupling case in full detail.

  13. Decoherence in chaotic and integrable systems: a random matrix approach

    Energy Technology Data Exchange (ETDEWEB)

    Gorin, T.; Seligman, T.H

    2003-03-17

    We study the influence of chaos and order on entanglement and decoherence. In view of applications in quantum computing and teleportation which should be able to work with arbitrarily complicated states, we pay particular attention to the behavior of random states. While studies with coherent states indicate that chaos accelerates decoherence and entanglement, we find that there is practically no difference between the chaotic and the integrable case, as far as random states are concerned. In the present studies we use unitary time evolution of the total system, and partial traces to emulate decoherence. Random matrix models are a natural choice to describe the dynamics of random states. The invariant aspects of chaos and order are then reflected in the different spectral statistics. We develop random matrix models for the evolution of entanglement for a large variety of situations, discussing the strong coupling case in full detail.

  14. MALDI mechanism of dihydroxybenzoic acid isomers: desorption of neutral matrix and analyte.

    Science.gov (United States)

    Liang, Chi Wei; Lee, Chih Hao; Lin, Yu-Jiun; Lee, Yuan Tseh; Ni, Chi Kung

    2013-05-01

    Angular resolved velocity distributions of laser desorbed neutral matrices (dihydroxybenzoic acids, DHB) and analytes (tryptophan) embedded in these matrices were investigated at 322 nm by a modified crossed molecular beam apparatus. Desorbed ions generated from MALDI were measured by a time-of-flight mass spectrometer. Desorptions of neutral matrix and analyte from 2,3-DHB, 2,4-DHB, 2,5-DHB, 2,6-DHB, and 3,5--DHB at 322 nm have similar properties, but the ion intensities are in the order 2,3DHB ≅ 2,6-DHB > 2,5-DHB ≅ 2,4-DHB > 3,5-DHB. It indicates that the combination of various parameters related to neutral species, including absorption coefficient, sublimation energy, contact of analyte and matrix in crystal, and plume dynamics of desorbed species are not crucial in the determination of MALDI process for DHB isomers. The difference of matrix activity of DHB isomers at this wavelength must result from the other properties, like the excited state lifetime, proton affinity, gas-phase basicity, acidity, ionization energy, or the other properties related to the primary reactions in ion generation.

  15. Response matrix of an extended Bonner sphere system

    International Nuclear Information System (INIS)

    We have developed a system of Bonner spheres designed for use around high-energy accelerators. The upper energy limit of the system was extended using a lead radiator, which acts as an energy converter via the (n,xn) reaction. In addition, we use 11C activation as an additional component integrated into the system and the spectra unfolding process. In the first version of the system, the lead radiator was present in only one sphere with diameter of 30.48 cm. The object of the present work was to investigate the geometry of the lead radiator and its use in moderators of several different sizes. As a result, we have developed a modular design and calculated the response matrix of the new system

  16. Response matrix of an extended Bonner sphere system

    CERN Document Server

    Vylet, V

    2002-01-01

    We have developed a system of Bonner spheres designed for use around high-energy accelerators. The upper energy limit of the system was extended using a lead radiator, which acts as an energy converter via the (n,xn) reaction. In addition, we use sup 1 sup 1 C activation as an additional component integrated into the system and the spectra unfolding process. In the first version of the system, the lead radiator was present in only one sphere with diameter of 30.48 cm. The object of the present work was to investigate the geometry of the lead radiator and its use in moderators of several different sizes. As a result, we have developed a modular design and calculated the response matrix of the new system.

  17. Efficiency of Gas-Phase Ion Formation in Matrix-Assisted Laser Desorption Ionization with 2,5-Dihydroxybenzoic Acid as Matrix

    International Nuclear Information System (INIS)

    Numbers of matrix- and analyte-derived ions and their sum in matrix-assisted laser desorption ionization (MALDI) of a peptide were measured using 2,5-dihydroxybenzoic acid (DHB) as matrix. As for MALDI with α-cyano-4-hydroxy cinnamic acid as matrix, the sum was independent of the peptide concentration in the solid sample, or was the same as that of pure DHB. This suggested that the matrix ion was the primary ion and that the peptide ion was generated by matrix-to-peptide proton transfer. Experimental ionization efficiencies of 10-5-10-4 for peptides and 10-8-10-7 for matrices are far smaller than 10.3-10.1 for peptides and 10-5-10-3 for matrices speculated by Hillenkamp and Karas. Number of gas-phase ions generated by MALDI was unaffected by laser wavelength or pulse energy. This suggests that the main role of photo-absorption in MALDI is not in generating ions via a multi-photon process but in ablating materials in a solid sample to the gas phase

  18. EFFECT OF ACIDITY ON ACID-SENSITIVE UV CURING SYSTEM

    Institute of Scientific and Technical Information of China (English)

    Qi-dao Chen; Bing Wu; Xiao-yin Hong

    1999-01-01

    By using diphenyliodonium salts with different counterions as photo acid generators (PAGs), the effect of acidity on ring-opening polymerization of epoxy monomers and polycondensation of polyol with hexamethoxymethyl melamine (HMMM) was studied. The result shows that the rate of ring-opening polymerization is evidently dependent on the acidity of the acid and strong photo-generated acid is required.However, there is a leveling effect in the polycondensation system; if the photo-generated acid is stronger than protonated HMMM, the acidity does not obviously affect the polycondensation rate.

  19. Nucleic acid based logical systems.

    Science.gov (United States)

    Han, Da; Kang, Huaizhi; Zhang, Tao; Wu, Cuichen; Zhou, Cuisong; You, Mingxu; Chen, Zhuo; Zhang, Xiaobing; Tan, Weihong

    2014-05-12

    Researchers increasingly visualize a significant role for artificial biochemical logical systems in biological engineering, much like digital logic circuits in electrical engineering. Those logical systems could be utilized as a type of servomechanism to control nanodevices in vitro, monitor chemical reactions in situ, or regulate gene expression in vivo. Nucleic acids (NA), as carriers of genetic information with well-regulated and predictable structures, are promising materials for the design and engineering of biochemical circuits. A number of logical devices based on nucleic acids (NA) have been designed to handle various processes for technological or biotechnological purposes. This article focuses on the most recent and important developments in NA-based logical devices and their evolution from in vitro, through cellular, even towards in vivo biological applications.

  20. Arsenic speciation and identification of monomethylarsonous acid and monomethylthioarsonic acid in a complex matrix.

    Science.gov (United States)

    Yathavakilla, Santha Ketavarapu V; Fricke, Michael; Creed, Patricia A; Heitkemper, Douglas T; Shockey, Nohora V; Schwegel, Carol; Caruso, Joseph A; Creed, John T

    2008-02-01

    Anion-exchange chromatography was utilized for speciation of arsenite (As(III)), arsenate (As(V)), dimethylarsinic acid (DMA(V)), monomethylarsonic acid (MMA(V)), monomethylarsonous acid (MMA(III)), and the new As species monomethylthioarsonic acid (MMTA), using inductively coupled plasma mass spectrometric (ICPMS) detection. MMA(III) and MMTA were identified for the first time in freeze-dried carrot samples that were collected over 25 years ago as part of a joint U.S. EPA, U.S. FDA, and USDA study on trace elements in agricultural crops. The discovery of MMA(III) and MMTA in terrestrial foods necessitated the analytical characterization of synthetic standards of both species, which were used for standard addition in carrot extracts. The negative ion mode, high-resolution electrospray mass spectrometry (HR-ESI-MS) data produced molecular ions of m/z 122.9418 and 154.9152 for MMA(III) and MMTA, respectively. However, ESI-MS was not sensitive enough to directly identify MMA(III) and MMTA in the carrot extracts. Therefore, to further substantiate the identification of MMA(III) and MMTA, two additional separations using an Ion-120 column were developed using the more sensitive ICPMS detection. The first separation used 20 mM tetramethylammonium hydroxide at pH 12.2 with MMA(III) eluting in less than 7 min. In the second separation, MMTA eluted at 11.2 min by utilizing 40 mM ammonium carbonate at pH 9.0. Oxidation of MMA(III) and MMTA to MMA(V) with hydrogen peroxide was observed for standards and carrot extracts alike. Several samples of carrots collected from local markets in 2006 were also analyzed and found to contain low levels of inorganic arsenic species. PMID:18181583

  1. Use of stirred tanks for studying matrix effects caused by inorganic acids, easily ionized elements and organic solvents in inductively coupled plasma atomic emission spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Paredes, Eduardo [Departamento de Quimica Analitica, Nutricion y Bromatologia, University of Alicante, 03080 Alicante (Spain); Maestre, Salvador E. [Departamento de Quimica Analitica, Nutricion y Bromatologia, University of Alicante, 03080 Alicante (Spain); Todoli, Jose L. [Departamento de Quimica Analitica, Nutricion y Bromatologia, University of Alicante, 03080 Alicante (Spain)]. E-mail: jose.todoli@ua.es

    2006-03-15

    A stirred tank was used for the first time to elucidate the mechanism responsible for inductively coupled plasma atomic emission spectroscopy (ICP-AES) matrix effects caused by inorganic, acids and easily ionized elements (EIEs), as well as organic, ethanol and acetic acid, compounds. In order to gradually increase the matrix concentration, a matrix solution was introduced inside a stirred container (tank) initially filled with an aqueous multielement standard. PolyTetraFluoroEthylene (PTFE) tubing was used to deliver the resulting solution to the liquid sample introduction system. Matrix concentration ranged from 0 to 2 mol l{sup -1} in the case of inorganic acids (i.e., nitric, sulfuric, hydrochloric and a mixture of them), from 0 to about 2500 mg l{sup -1} for EIEs (i.e., sodium, calcium and mixtures of both) and from 0% to 15%, w/w for organic compounds. Up to 40-50 different solutions were prepared and measured in a period of time shorter than 6-7 min. This investigation was carried out in terms of emission intensity and tertiary aerosols characteristics. The experimental setup used in the present work allowed to thoroughly study the effect of matrix concentration on analytical signal. Generally speaking, the experiments concerning tertiary aerosol characterization revealed that, in the case of inorganic acids and EIEs, the mechanism responsible for changes in aerosol characteristics was the droplet fission. In contrast, for organic matrices it was found that the interference was caused by a change in both aerosol transport and plasma thermal characteristics. The extent of the interferences caused by organic as well as inorganic compounds was compared for a set of 14 emission lines through a wide range of matrix concentrations. With a stirred tank, it is possible to choose an efficient internal standard for any given matrix composition. The time required to complete this procedure was shorter than 7 min.

  2. The Expression of Bone Morphogenetic Protein 2 and Matrix Metalloproteinase 2 through Retinoic Acid Receptor Beta Induced by All-Trans Retinoic Acid in Cultured ARPE-19 Cells

    OpenAIRE

    Zhenya Gao; Lijun Huo; Dongmei Cui; Xiao Yang; Junwen Zeng

    2016-01-01

    Purpose All-trans retinoic acid (ATRA) plays an important role in ocular development. Previous studies found that retinoic acid could influence the metabolism of scleral remodeling by promoting retinal pigment epithelium (RPE) cells to secrete secondary signaling factors. The purpose of this study was to investigate whether retinoic acid affected secretion of bone morphogenetic protein 2 (BMP-2) and matrix metalloproteinase 2 (MMP-2) and to explore the signaling pathway of retinoic acid in cu...

  3. Analytical solutions of solute transport in a fracture-matrix system with different reaction rates for fracture and matrix

    Science.gov (United States)

    Zhu, Yonghui; Zhan, Hongbin; Jin, Menggui

    2016-08-01

    This study deals with the problem of reactive solute transport in a fracture-matrix system using both analytical and numerical modeling methods. The groundwater flow velocity in the fracture is assumed to be high enough (no less than 0.1 m/day) to ensure the advection-dominant transport in the fracture. The problem includes advection along the fracture, transverse diffusion in the matrix, with linear sorption as well as first-order reactions operative in both the fracture and the matrix. A constant-concentration boundary condition and a decay source boundary condition in the fracture are considered. With a constant-concentration source, we obtain closed-form analytical solutions that account for the transport without reaction as well as steady-state solutions with different first-order reactions in the two media. With a decay source, a semi-analytical solution is obtained. The analytical and semi-analytical solutions are in excellent agreement with the numerical simulation results obtained using COMSOL Multiphysics. Sensitivity analysis is conducted to assess the relative importance of matrix diffusion coefficient, fracture aperture, and matrix porosity. We conclude that the first-order reaction as well as the matrix diffusion in the fractured rock would decrease the solute peak concentration and shorten the penetration distance into the fracture. The solutions can be applied to assess the spatial-temporal distribution of concentrations in the fracture and the matrix as well as to assess the contaminant mass stored in the rock matrix. All of these are useful for designing remediation plans for contaminated fractured rocks or for risk assessment of contaminated fracture-matrix systems.

  4. Regulation of ovarian function by the matrix metalloproteinase system

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    @@ In most organs of mammals, cyclic remodelling of tissues after morphogenesis is minimal; however, repro-ductive tissues of female animals including endometrium, mammary gland, ovarian follicle and corpus luteum un-dergo growth, maturation and involution at various stages in the reproductive cycle or lifespan of the animal. Recon-struction of the extracellular matrix (ECM) is required for the dynamic tissue reorganization characteristic of these tissues. The ECM consists of proteinaceous and nonpro-teinaceous molecules that provide the tissue-specific, ex-tracellular architecture to which cells attach. Furthermore, interaction of cellular receptors with proteins of the ECM can regulate cellular structure, second messenger genera-tion and gene expression. Maintenance of ECM homeo-stasis depends largely on coordinated action of matrix metalloproteinases (MMPs) and tissue inhibitors of met-alloproteinases (TIMPs)-- an important proteinase sys-tem responsible for degradating and remodelling of ECM[1]. MMPs/TIMPs have been recognized as the cru-cial role players in regulating follicular and luteal function for their extensive involvements in the cyclic changes of dynamic ovarian tissues. In recent years, literature that MMP system has important roles in ovary is accumulating. The focus of this review is on the effects of MMPs and their inhibitors, TIMPs on follicular growth, atresia, ovu-lation, luteal development, and luteolysis. Emphasis has been given to the recent progress in the new field when-ever possible.

  5. Theoretical Studies of the Relaxation Matrix for Molecular Systems

    Science.gov (United States)

    Ma, Qiancheng; Boulet, C.

    2016-06-01

    The phenomenon of collisional transfer of intensity due to line mixing has an increasing importance for atmospheric monitoring. From a theoretical point of view, all relevant information about the collisional processes is contained in the relaxation matrix where the diagonal elements give half-widths and shifts, and the off-diagonal elements correspond to line interferences. For simple systems such as those consisting of diatom-atom or diatom-diatom, accurate fully quantum calculations based on interaction potentials are feasible. However, fully quantum calculations become unrealistic for more complex systems. On the other hand, the semi-classical Robert-Bonamy formalism, which has been widely used to calculate half-widths and shifts for decades, fails in calculating the off-diagonal matrix elements resulting from applying the isolated line approximation. As a result, in order to simulate atmospheric spectra where the effects from line mixing are important, semi-empirical fitting or scaling laws such as the energy corrected sudden (ECS) and the infinite order sudden (IOS) models are commonly used. Recently, we have found that in developing this semi-classical line shape theory, to rely on the isolated line approximation is not necessary. By eliminating this unjustified assumption, and accurately evaluating matrix elements of the exponential operators, we have developed a more capable formalism that enables one not only to reduce uncertainties for calculated half-widths and shifts, but also to calculate the whole relaxation matrix. This implies that we can address the line mixing with the semi-classical theory based on interaction potentials between molecular absorber and molecular perturber. We have applied this formalism for Raman and infrared spectra of linear and asymmetric-top molecules. Recently, the method has been extended into symmetric-tops with inverse symmetry such as the NH3 molecule. Our calculated half-widths of NH3 lines in the νb{1} and the pure

  6. Extracellular matrix assembly in extreme acidic eukaryotic biofilms and their possible implications in heavy metal adsorption

    Energy Technology Data Exchange (ETDEWEB)

    Aguilera, Angeles [Centro de Astrobiologia (INTA-CSIC), Carretera de Ajalvir Km 4, Torrejon de Ardoz, 28850 Madrid (Spain)], E-mail: aguileraba@inta.es; Souza-Egipsy, Virginia [Centro de Astrobiologia (INTA-CSIC), Carretera de Ajalvir Km 4, Torrejon de Ardoz, 28850 Madrid (Spain); San Martin-Uriz, Patxi [Centro de Biologia Molecular (UAM-CSIC), Universidad Autonoma de Madrid, Cantoblanco, 28049 Madrid (Spain); Amils, Ricardo [Centro de Astrobiologia (INTA-CSIC), Carretera de Ajalvir Km 4, Torrejon de Ardoz, 28850 Madrid (Spain); Centro de Biologia Molecular (UAM-CSIC), Universidad Autonoma de Madrid, Cantoblanco, 28049 Madrid (Spain)

    2008-07-30

    To evaluate the importance of the extracellular matrix in relation to heavy metal binding capacity in extreme acidic environments, the extracellular polymeric substances (EPS) composition of 12 biofilms isolated from Rio Tinto (SW, Spain) was analyzed. Each biofilm was composed mainly by one or two species of eukaryotes, although other microorganisms were present. EPS ranged from 130 to 439 mg g{sup -1} biofilm dry weight, representing between 15% and the 40% of the total biofilm dry weight (DW). Statistically significant differences (p < 0.05) were found in the amount of total EPS extracted from biofilms dominated by the same organism at different sampling points. The amount of EPS varied among different biofilms collected from the same sampling location. Colloidal EPS ranged from 42 to 313 mg g{sup -1} dry weight; 10% to 30% of the total biofilm dry weight. Capsular EPS ranged from 50 to 318 mg g{sup -1} dry weight; 5% to 30% of the total biofilm dry weight. Seven of the 12 biofilms showed higher amounts of capsular than colloidal EPS (p < 0.05). Total amount of EPS decreased when total cell numbers and pH increased. There was a positive correlation between EPS concentration and heavy metal concentration in the water. Observations by low temperature scanning electron microscopy (LTSEM) revealed the mineral adsorption in the matrix of EPS and onto the cell walls. EPS in all biofilms were primarily composed of carbohydrates, heavy metals and humic acid, plus small quantities of proteins and DNA. After carbohydrates, heavy metals were the second main constituents of the extracellular matrix. Their total concentrations ranged from 3 to 32 mg g{sup -1} biofilm dry weight, reaching up to 16% of the total composition. In general, the heavy metal composition of the EPS extracted from the biofilms closely resembled the metal composition of the water from which the biofilms were collected.

  7. Group classification of systems of non-linear reaction-diffusion equations with general diffusion matrix. II. Generalized Turing systems

    OpenAIRE

    Nikitin, A. G.

    2004-01-01

    Group classification of systems of two coupled nonlinear reaction-diffusion equation with a diagonal diffusion matrix is carried out. Symmetries of diffusion systems with singular diffusion matrix and additional first order derivative terms are described.

  8. Evaluating mirror alignment systems using the optical sensing matrix

    Energy Technology Data Exchange (ETDEWEB)

    Mantovani, M [Universita di Siena, INFN Pisa (Italy); Freise, A [School of Physics and Astronomy, University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom)], E-mail: mantovan@ego-gw.it

    2008-07-15

    The most sensitive gravitational-wave detectors today are based on large-scale laser interferometers whose optics are suspended from pendulums to decouple the instrument from seismic motion. Complex control systems are required to set and maintain the microscopic position of each mirror at a precisely defined value. Such control systems use the interferometer signals as input signals, and ideally it is designed such that the degrees of freedom (mirror positions) are well decoupled in the interferometer signals. However, this is not always feasible, in particular the mirror alignment control signals in interferometric gravitational wave detectors often show strong couplings between the different degrees of freedom. In this paper we will describe a simple and powerful method to quantify in advance the performances of an alignment control system by analyzing the optical matrix of the proposed read-out system. We will motivate the method using a Fabry-Perot cavity as an example, and we will further present results for the Virgo alignment system where this method was used to characterize and improve the alignment sensing scheme.

  9. Random matrix theory for pseudo-Hermitian systems: Cyclic blocks

    Indian Academy of Sciences (India)

    Sudhir R Jain; Shashi C L Srivastava

    2009-12-01

    We discuss the relevance of random matrix theory for pseudo-Hermitian systems, and, for Hamiltonians that break parity and time-reversal invariance . In an attempt to understand the random Ising model, we present the treatment of cyclic asymmetric matrices with blocks and show that the nearest-neighbour spacing distributions have the same form as obtained for the matrices with scalar entries. We also summarize the theory for random cyclic matrices with scalar entries. We have also found that for block matrices made of Hermitian and pseudo-Hermitian sub-blocks of the form appearing in Ising model depart from the known results for scalar entries. However, there is still similarity in trends even in log–log plots.

  10. Investigations on the effect of antioxidant type and concentration and model system matrix on acrylamide formation in model Maillard reaction systems.

    Science.gov (United States)

    Constantinou, Costas; Koutsidis, Georgios

    2016-04-15

    The formation of acrylamide in model Maillard reaction systems containing phenolic compounds was examined, with regards to phenolic type, concentration, and model system matrix. In dry glyoxal/asparagine waxy maize starch (WMS) systems, 9 out of 10 examined phenolics demonstrated an inhibiting effect, with the most significant reductions (55-60%) observed for caffeoylquinic acids. In WMS glucose/asparagine systems, examination of three different concentrations (0.1, 0.5 and 1 μmol/g WMS) suggested a 'minimum effective concentration' for epicatechin and caffeic acid, whilst addition of caffeoylquinic acids resulted in dose-dependent acrylamide reduction (25-75%). The discordant results of further studies utilising different matrices (dry and wet-to-dry) indicated that, apart from the nature and chemical reactivity, the matrix and the physical state of the reactants might be important for acrylamide formation. PMID:26617015

  11. Investigations on the effect of antioxidant type and concentration and model system matrix on acrylamide formation in model Maillard reaction systems.

    Science.gov (United States)

    Constantinou, Costas; Koutsidis, Georgios

    2016-04-15

    The formation of acrylamide in model Maillard reaction systems containing phenolic compounds was examined, with regards to phenolic type, concentration, and model system matrix. In dry glyoxal/asparagine waxy maize starch (WMS) systems, 9 out of 10 examined phenolics demonstrated an inhibiting effect, with the most significant reductions (55-60%) observed for caffeoylquinic acids. In WMS glucose/asparagine systems, examination of three different concentrations (0.1, 0.5 and 1 μmol/g WMS) suggested a 'minimum effective concentration' for epicatechin and caffeic acid, whilst addition of caffeoylquinic acids resulted in dose-dependent acrylamide reduction (25-75%). The discordant results of further studies utilising different matrices (dry and wet-to-dry) indicated that, apart from the nature and chemical reactivity, the matrix and the physical state of the reactants might be important for acrylamide formation.

  12. 4-Chloro-α-cyanocinnamic acid is an efficient soft matrix for cyanocobalamin detection in foodstuffs by matrix-assisted laser desorption/ionization mass spectrometry (MALDI MS).

    Science.gov (United States)

    Calvano, Cosima Damiana; Ventura, Giovanni; Palmisano, Francesco; Cataldi, Tommaso R I

    2016-09-01

    4-Chloro-α-cyanocinnamic acid (ClCCA) is a very useful matrix able to give the protonated adduct [M+H](+) of intact cyanocobalamin (CNCbl) as the base peak (m/z 1355.58) in matrix-assisted laser desorption/ionization (MALDI) mass spectrometry (MS). The only fragment observed is [M-CN + H](+•) formed through the facile (•) CN neutral loss reflecting the fairly low Co-C bond energy. All other investigated proton transfer matrices, including α-cyano-4-hydroxycinnamic acid, para-nitroaniline and 2,5-dihydroxybenzoic acid, give rise to a complete decyanation of CNCbl with concomitant formation of [M-CN + H](+•) , [M-CN + Na](+•) and [M-CN + K](+•) adducts at m/z 1329.57, 1351.55 and 1367.51, respectively. Depending on the matrix used, a variable degree of fragmentation involving the α-side axial ligand was observed. A plausible explanation of the specific behaviour of 4-chloro-α-cyanocinnamic acid as a soft matrix is discussed. Tandem mass spectra of both [M + H](+) and [M-CN + H](+•) ions were obtained and product ions successfully assigned. The possibility of detecting the protonated adduct of intact CNCbl was exploited in foodstuff samples such as cow milk and hen egg yolk by MALDI tandem MS upon sample extraction. We believe that our data provide strong basis for the application of MALDI tandem MS in the qualitative analysis of natural CNCbl, including fish, liver and meat samples. Copyright © 2016 John Wiley & Sons, Ltd. PMID:27468135

  13. 4-Chloro-α-cyanocinnamic acid is an efficient soft matrix for cyanocobalamin detection in foodstuffs by matrix-assisted laser desorption/ionization mass spectrometry (MALDI MS).

    Science.gov (United States)

    Calvano, Cosima Damiana; Ventura, Giovanni; Palmisano, Francesco; Cataldi, Tommaso R I

    2016-09-01

    4-Chloro-α-cyanocinnamic acid (ClCCA) is a very useful matrix able to give the protonated adduct [M+H](+) of intact cyanocobalamin (CNCbl) as the base peak (m/z 1355.58) in matrix-assisted laser desorption/ionization (MALDI) mass spectrometry (MS). The only fragment observed is [M-CN + H](+•) formed through the facile (•) CN neutral loss reflecting the fairly low Co-C bond energy. All other investigated proton transfer matrices, including α-cyano-4-hydroxycinnamic acid, para-nitroaniline and 2,5-dihydroxybenzoic acid, give rise to a complete decyanation of CNCbl with concomitant formation of [M-CN + H](+•) , [M-CN + Na](+•) and [M-CN + K](+•) adducts at m/z 1329.57, 1351.55 and 1367.51, respectively. Depending on the matrix used, a variable degree of fragmentation involving the α-side axial ligand was observed. A plausible explanation of the specific behaviour of 4-chloro-α-cyanocinnamic acid as a soft matrix is discussed. Tandem mass spectra of both [M + H](+) and [M-CN + H](+•) ions were obtained and product ions successfully assigned. The possibility of detecting the protonated adduct of intact CNCbl was exploited in foodstuff samples such as cow milk and hen egg yolk by MALDI tandem MS upon sample extraction. We believe that our data provide strong basis for the application of MALDI tandem MS in the qualitative analysis of natural CNCbl, including fish, liver and meat samples. Copyright © 2016 John Wiley & Sons, Ltd.

  14. Hypohalous acids contribute to renal extracellular matrix damage in experimental diabetes.

    Science.gov (United States)

    Brown, Kyle L; Darris, Carl; Rose, Kristie Lindsey; Sanchez, Otto A; Madu, Hartman; Avance, Josh; Brooks, Nickolas; Zhang, Ming-Zhi; Fogo, Agnes; Harris, Raymond; Hudson, Billy G; Voziyan, Paul

    2015-06-01

    In diabetes, toxic oxidative pathways are triggered by persistent hyperglycemia and contribute to diabetes complications. A major proposed pathogenic mechanism is the accumulation of protein modifications that are called advanced glycation end products. However, other nonenzymatic post-translational modifications may also contribute to pathogenic protein damage in diabetes. We demonstrate that hypohalous acid-derived modifications of renal tissues and extracellular matrix (ECM) proteins are significantly elevated in experimental diabetic nephropathy. Moreover, diabetic renal ECM shows diminished binding of α1β1 integrin consistent with the modification of collagen IV by hypochlorous (HOCl) and hypobromous acids. Noncollagenous (NC1) hexamers, key connection modules of collagen IV networks, are modified via oxidation and chlorination of tryptophan and bromination of tyrosine residues. Chlorotryptophan, a relatively minor modification, has not been previously found in proteins. In the NC1 hexamers isolated from diabetic kidneys, levels of HOCl-derived oxidized and chlorinated tryptophan residues W(28) and W(192) are significantly elevated compared with nondiabetic controls. Molecular dynamics simulations predicted a more relaxed NC1 hexamer tertiary structure and diminished assembly competence in diabetes; this was confirmed using limited proteolysis and denaturation/refolding. Our results suggest that hypohalous acid-derived modifications of renal ECM, and specifically collagen IV networks, contribute to functional protein damage in diabetes.

  15. Correction of Tear Trough Deformity With a Cohesive Polydensified Matrix Hyaluronic Acid: A Case Series.

    Science.gov (United States)

    Huber-Vorländer, Jürgen; Kürten, Martin

    2015-01-01

    The tear trough or infraorbital hollow is a challenging area to treat, and only a few fillers are suitable for this delicate area. We report on a European case series of six subjects with mild to severe tear troughs who received treatment with cohesive polydensified matrix (CPM®) technology hyaluronic acid gel (Belotero® Balance). The product was injected as small depots (up to ten small boli 0.2 mL maximum each per side) at the supraperiosteal level along or below the orbital rim. Follow-up visits took place at 1, 3, 6, and 9 months after injection for independent evaluation of the clinical effect using the Merz Aesthetics Scale™ for infraorbital hollows and the Global Aesthetic Improvement Scale. Adverse events were also recorded. Mean hollowness scores were considerably improved compared with baseline in all subjects. In all women, the improvements remained throughout the 9-month study, with none reverting to their baseline score. Subjects' satisfaction with treatment was very high throughout the study, and all women stated that they would repeat treatment with the same product. The CPM hyaluronic acid gel was well tolerated. CPM hyaluronic acid gel is a safe and effective treatment for the tear trough area. PMID:26605822

  16. Superabsorbent biphasic system based on poly(lactic acid) and poly(acrylic acid)

    Science.gov (United States)

    Sartore, Luciana; Pandini, Stefano; Baldi, Francesco; Bignotti, Fabio

    2016-05-01

    In this research work, biocomposites based on crosslinked particles of poly(acrylic acid), commonly used as superabsorbent polymer (SAP), and poly-L-lactic acid (PLLA) were developed to elucidate the role of the filler (i.e., polymeric crosslinked particles) on the overall physico-mechanical behavior and to obtain superabsorbent thermoplastic products. Samples prepared by melt-blending of components in different ratios showed a biphasic system with a regular distribution of particles, with diameter ranging from 5 to 10 μm, within the PLLA polymeric matrix. The polymeric biphasic system, coded PLASA i.e. superabsorbent poly(lactic acid), showed excellent swelling properties, demonstrating that cross-linked particles retain their superabsorbent ability, as in their free counterparts, even if distributed in a thermoplastic polymeric matrix. The thermal characteristics of the biocomposites evidence enhanced thermal stability in comparison with neat PLLA and also mechanical properties are markedly modified by addition of crosslinked particles which induce regular stiffening effect. Furthermore, in aqueous environments the particles swell and are leached from PLLA matrix generating very high porosity. These new open-pore PLLA foams, produced in absence of organic solvents and chemical foaming agents, with good physico-mechanical properties appear very promising for several applications, for instance in tissue engineering for scaffold production.

  17. The shell matrix of the freshwater mussel Unio pictorum (Paleoheterodonta, Unionoida). Involvement of acidic polysaccharides from glycoproteins in nacre mineralization.

    Science.gov (United States)

    Marie, Benjamin; Luquet, Gilles; Pais De Barros, Jean-Paul; Guichard, Nathalie; Morel, Sylvain; Alcaraz, Gérard; Bollache, Loïc; Marin, Frédéric

    2007-06-01

    Among molluscs, the shell biomineralization process is controlled by a set of extracellular macromolecular components secreted by the calcifying mantle. In spite of several studies, these components are mainly known in bivalves from only few members of pteriomorph groups. In the present case, we investigated the biochemical properties of the aragonitic shell of the freshwater bivalve Unio pictorum (Paleoheterodonta, Unionoida). Analysis of the amino acid composition reveals a high amount of glycine, aspartate and alanine in the acid-soluble extract, whereas the acid-insoluble one is rich in alanine and glycine. Monosaccharidic analysis indicates that the insoluble matrix comprises a high amount of glucosamine. Furthermore, a high ratio of the carbohydrates of the soluble matrix is sulfated. Electrophoretic analysis of the acid-soluble matrix revealed discrete bands. Stains-All, Alcian Blue, periodic acid/Schiff and autoradiography with (45)Ca after electrophoretic separation revealed three major polyanionic calcium-binding glycoproteins, which exhibit an apparent molecular mass of 95, 50 and 29 kDa, respectively. Two-dimensional gel electrophoresis shows that these bands, provisionally named P95, P50 and P29, are composed of numerous isoforms, the majority of which have acidic isoelectric points. Chemical deglycosylation of the matrix with trifluoromethanesulfonic acid induces a drastic shift of both the apparent molecular mass and the isoelectric point of these matrix components. This treatment induces also a modification of the shape of CaCO(3) crystals grown in vitro and a loss of the calcium-binding ability of two of the main matrix proteins (P95 and P50). Our findings strongly suggest that post-translational modifications display important functions in mollusc shell calcification.

  18. The shell matrix of the freshwater mussel Unio pictorum (Paleoheterodonta, Unionoida). Involvement of acidic polysaccharides from glycoproteins in nacre mineralization.

    Science.gov (United States)

    Marie, Benjamin; Luquet, Gilles; Pais De Barros, Jean-Paul; Guichard, Nathalie; Morel, Sylvain; Alcaraz, Gérard; Bollache, Loïc; Marin, Frédéric

    2007-06-01

    Among molluscs, the shell biomineralization process is controlled by a set of extracellular macromolecular components secreted by the calcifying mantle. In spite of several studies, these components are mainly known in bivalves from only few members of pteriomorph groups. In the present case, we investigated the biochemical properties of the aragonitic shell of the freshwater bivalve Unio pictorum (Paleoheterodonta, Unionoida). Analysis of the amino acid composition reveals a high amount of glycine, aspartate and alanine in the acid-soluble extract, whereas the acid-insoluble one is rich in alanine and glycine. Monosaccharidic analysis indicates that the insoluble matrix comprises a high amount of glucosamine. Furthermore, a high ratio of the carbohydrates of the soluble matrix is sulfated. Electrophoretic analysis of the acid-soluble matrix revealed discrete bands. Stains-All, Alcian Blue, periodic acid/Schiff and autoradiography with (45)Ca after electrophoretic separation revealed three major polyanionic calcium-binding glycoproteins, which exhibit an apparent molecular mass of 95, 50 and 29 kDa, respectively. Two-dimensional gel electrophoresis shows that these bands, provisionally named P95, P50 and P29, are composed of numerous isoforms, the majority of which have acidic isoelectric points. Chemical deglycosylation of the matrix with trifluoromethanesulfonic acid induces a drastic shift of both the apparent molecular mass and the isoelectric point of these matrix components. This treatment induces also a modification of the shape of CaCO(3) crystals grown in vitro and a loss of the calcium-binding ability of two of the main matrix proteins (P95 and P50). Our findings strongly suggest that post-translational modifications display important functions in mollusc shell calcification. PMID:17488282

  19. Effects of spray-drying on w/o/w multiple emulsions prepared from a stearic acid matrix.

    Science.gov (United States)

    Mlalila, Nichrous; Swai, Hulda; Kalombo, Lonji; Hilonga, Askwar

    2014-01-01

    The goal of this study was to explore the effects of spray-drying on w/o/w double emulsions of methyltestosterone (MT) loaded in a stearic acid matrix. MT-loaded nanoparticles were formulated by a water-in-oil-in-water emulsion technique using 50, 75, and 100 mg of stearic acid, 2% and 3% w/v polyvinyl alcohol, 5% w/v lactose, and 0.2% w/v chitosan. The emulsions were immediately spray-dried based on an optimized model of inlet temperature and pump rate, and characterized for optimized responses with regard to particle size, polydispersity index, and zeta potential, for both emulsion and powder samples. Dynamic light scattering analysis shown that the nanoparticles increased in size with increasing concentrations of polyvinyl alcohol and stearic acid. Scanning electron microscopy indicated that the MT-loaded nanoparticles were spherical in shape, had a smooth surface, and were in an amorphous state, which was confirmed by differential scanning calorimetry. These MT-loaded nanoparticles are a promising candidate carrier for the delivery of MT; however, further studies are needed in order to establish the stability of the system and the cargo release profile under normal conditions of use. PMID:25489238

  20. 3matrix and 3motif: a protein structure visualization system for conserved sequence motifs

    OpenAIRE

    Bennett, Steven P.; Lu, Lin; Brutlag, Douglas L.

    2003-01-01

    Computational methods such as sequence alignment and motif construction are useful in grouping related proteins into families, as well as helping to annotate new proteins of unknown function. These methods identify conserved amino acids in protein sequences, but cannot determine the specific functional or structural roles of conserved amino acids without additional study. In this work, we present 3matrix (http://3matrix.stanford.edu) and 3motif (http://3motif.stanford.edu), a web-based sequen...

  1. Utilizing cell-matrix interactions to modulate gene transfer to stem cells inside hyaluronic acid hydrogels.

    Science.gov (United States)

    Gojgini, Shiva; Tokatlian, Talar; Segura, Tatiana

    2011-10-01

    The effective delivery of DNA locally would increase the applicability of gene therapy in tissue regeneration, where diseased tissue is to be repaired in situ. One promising approach is to use hydrogel scaffolds to encapsulate and deliver plasmid DNA in the form of nanoparticles to the diseased tissue, so that cells infiltrating the scaffold are transfected to induce regeneration. This study focuses on the design of a DNA nanoparticle-loaded hydrogel scaffold. In particular, this study focuses on understanding how cell-matrix interactions affect gene transfer to adult stem cells cultured inside matrix metalloproteinase (MMP) degradable hyaluronic acid (HA) hydrogel scaffolds. HA was cross-linked to form a hydrogel material using a MMP degradable peptide and Michael addition chemistry. Gene transfer inside these hydrogel materials was assessed as a function of polyplex nitrogen to phosphate ratio (N/P = 5 to 12), matrix stiffness (100-1700 Pa), RGD (Arg-Gly-Asp) concentration (10-400 μM), and RGD presentation (0.2-4.7 RGDs per HA molecule). All variables were found to affect gene transfer to mouse mensenchymal stem cells culture inside the DNA loaded hydrogels. As expected, higher N/P ratios lead to higher gene transfer efficiency but also higher toxicity; softer hydrogels resulted in higher transgene expression than stiffer hydrogels, and an intermediate RGD concentration and RGD clustering resulted in higher transgene expression. We believe that the knowledge gained through this in vitro model can be utilized to design better scaffold-mediated gene delivery for local gene therapy.

  2. Derivation of an amino acid similarity matrix for peptide:MHC binding and its application as a Bayesian prior

    Directory of Open Access Journals (Sweden)

    Sette Alessandro

    2009-11-01

    Full Text Available Abstract Background Experts in peptide:MHC binding studies are often able to estimate the impact of a single residue substitution based on a heuristic understanding of amino acid similarity in an experimental context. Our aim is to quantify this measure of similarity to improve peptide:MHC binding prediction methods. This should help compensate for holes and bias in the sequence space coverage of existing peptide binding datasets. Results Here, a novel amino acid similarity matrix (PMBEC is directly derived from the binding affinity data of combinatorial peptide mixtures. Like BLOSUM62, this matrix captures well-known physicochemical properties of amino acid residues. However, PMBEC differs markedly from existing matrices in cases where residue substitution involves a reversal of electrostatic charge. To demonstrate its usefulness, we have developed a new peptide:MHC class I binding prediction method, using the matrix as a Bayesian prior. We show that the new method can compensate for missing information on specific residues in the training data. We also carried out a large-scale benchmark, and its results indicate that prediction performance of the new method is comparable to that of the best neural network based approaches for peptide:MHC class I binding. Conclusion A novel amino acid similarity matrix has been derived for peptide:MHC binding interactions. One prominent feature of the matrix is that it disfavors substitution of residues with opposite charges. Given that the matrix was derived from experimentally determined peptide:MHC binding affinity measurements, this feature is likely shared by all peptide:protein interactions. In addition, we have demonstrated the usefulness of the matrix as a Bayesian prior in an improved scoring-matrix based peptide:MHC class I prediction method. A software implementation of the method is available at: http://www.mhc-pathway.net/smmpmbec.

  3. Science of Hyaluronic Acid Beyond Filling: Fibroblasts and Their Response to the Extracellular Matrix.

    Science.gov (United States)

    Landau, Marina; Fagien, Steven

    2015-11-01

    Loss of viscoelasticity is one of the primarily signs of skin aging, followed by appearance of visible wrinkles. Hyaluronic acid (HA)-based fillers are widely used to fill wrinkles and compensate for volume loss. Recent clinical observations demonstrate persistence of the filling effect longer than the biological availability of the filler. Stimulation of new collagen by cross-linked HA and up-regulation of elastin have been suggested as possible explanation to this observation and have been supported experimentally. Cross-linked HA substitutes for fragmented collagen in restoring extracellular matrix required for normal activity of fibroblasts, such as collagen and elastin production. To restore extracellular matrix efficiently, serial monthly treatments are required. Boosting of facial and nonfacial skin through fibroblast activation is a new indication for HA-based products. Injectable HA has also been recently registered in Europe as agents specific for the improvement of skin quality (Restylane Skinboosters). Further explanation of the possible mechanisms supported by long-term clinical examples is presented herein. PMID:26441098

  4. Fluorometric quantification of polyphosphate in environmental plankton samples: extraction protocols, matrix effects, and nucleic acid interference.

    Science.gov (United States)

    Martin, Patrick; Van Mooy, Benjamin A S

    2013-01-01

    Polyphosphate (polyP) is a ubiquitous biochemical with many cellular functions and comprises an important environmental phosphorus pool. However, methodological challenges have hampered routine quantification of polyP in environmental samples. We tested 15 protocols to extract inorganic polyphosphate from natural marine samples and cultured cyanobacteria for fluorometric quantification with 4',6-diamidino-2-phenylindole (DAPI) without prior purification. A combination of brief boiling and digestion with proteinase K was superior to all other protocols, including other enzymatic digestions and neutral or alkaline leaches. However, three successive extractions were required to extract all polyP. Standard addition revealed matrix effects that differed between sample types, causing polyP to be over- or underestimated by up to 50% in the samples tested here. Although previous studies judged that the presence of DNA would not complicate fluorometric quantification of polyP with DAPI, we show that RNA can cause significant interference at the wavelengths used to measure polyP. Importantly, treating samples with DNase and RNase before proteinase K digestion reduced fluorescence by up to 57%. We measured particulate polyP along a North Pacific coastal-to-open ocean transect and show that particulate polyP concentrations increased toward the open ocean. While our final method is optimized for marine particulate matter, different environmental sample types may need to be assessed for matrix effects, extraction efficiency, and nucleic acid interference.

  5. Oxidizing gel formulation for nuclear decontamination: rheological and acidic properties of the organic matrix and its ozonolysis

    International Nuclear Information System (INIS)

    An acidic and oxidizing gel was formulated with a purely organic matrix, xanthan gum, at low concentrations (1 to 2 wt %). This polymer gel was investigated in various media (aqueous, acidic and ceric) by means of rheology: shear thinning behaviour, thixotropy, yield stress... Evidences of unexpected rheological properties in highly concentrated media show that xanthan is quite convenient for industrial projection of this type of gel on metallic walls in nuclear plants, notwithstanding its time-limited resistance to oxidation (about a few hours). Complexation mechanisms between ceric species and polar sites of the polymer led us to characterise acidic properties of our xanthan sample by potentiometric titration and 1H NMR techniques. The matrix was finally treated by ozonolysis to suppress organic residues, as required to handle nuclear wastes. In acidic medium, ozonolysis of the gel was achieved successfully while in acidic and ceric medium this process showed limited efficiency, needing further investigation to be clarified. (author)

  6. Towards Acid-Tolerated Ethanol Dehydration: Chitosan-Based Mixed Matrix Membranes Containing Cyano-Bridged Coordination Polymer Nanoparticles.

    Science.gov (United States)

    Wu, C-W; Kang, Chao-Hsiang; Lin, Yi-Feng; Tung, Kuo-Lun; Deng, Yu-Heng; Ahamad, Tansir; Alshehri, Saad M; Suzuki, Norihiro; Yamauchi, Yusuke

    2016-04-01

    Prussian blue (PB) nanoparticles, one of many cyano-bridged coordination polymers, are successfully incorporated into chitosan (CS) polymer to prepare PB/CS mixed matrix membranes (MMMs). The PB nanoparticles are uniformly distributed in the MMMs without the collapse of the original PB structure. As-prepared PB/CS MMMs are used for ethanol dehydration at 25 °C in the pervaporation process. The effect of loading PB in CS matrix on pervaporation performance is carefully investigated. The PB/CS membrane with 30 wt% PB loading shows the best performance with a permeate flux of 614 g. m-2 . h-1 and a separation factor of 1472. The pervaporation using our PB/CS membranes exhibits outstanding performance in comparison with the previously reported CS-based membranes and MMMs. Furthermore, the addition of PB allows PB/CS MMMs to be tolerant of acidic environment. The present work demonstrates good pervaporation performance of PB/CS MMMs for the separation of an ethanol/water (90:10 in wt%) solution. Our new system provides an opportunity for dehydration of bioethanol in the future. PMID:27451778

  7. Towards Acid-Tolerated Ethanol Dehydration: Chitosan-Based Mixed Matrix Membranes Containing Cyano-Bridged Coordination Polymer Nanoparticles.

    Science.gov (United States)

    Wu, C-W; Kang, Chao-Hsiang; Lin, Yi-Feng; Tung, Kuo-Lun; Deng, Yu-Heng; Ahamad, Tansir; Alshehri, Saad M; Suzuki, Norihiro; Yamauchi, Yusuke

    2016-04-01

    Prussian blue (PB) nanoparticles, one of many cyano-bridged coordination polymers, are successfully incorporated into chitosan (CS) polymer to prepare PB/CS mixed matrix membranes (MMMs). The PB nanoparticles are uniformly distributed in the MMMs without the collapse of the original PB structure. As-prepared PB/CS MMMs are used for ethanol dehydration at 25 °C in the pervaporation process. The effect of loading PB in CS matrix on pervaporation performance is carefully investigated. The PB/CS membrane with 30 wt% PB loading shows the best performance with a permeate flux of 614 g. m-2 . h-1 and a separation factor of 1472. The pervaporation using our PB/CS membranes exhibits outstanding performance in comparison with the previously reported CS-based membranes and MMMs. Furthermore, the addition of PB allows PB/CS MMMs to be tolerant of acidic environment. The present work demonstrates good pervaporation performance of PB/CS MMMs for the separation of an ethanol/water (90:10 in wt%) solution. Our new system provides an opportunity for dehydration of bioethanol in the future.

  8. Modal cost analysis for linear matrix-second-order systems

    Science.gov (United States)

    Skelton, R. E.; Hughes, P. C.

    1980-01-01

    Reduced models and reduced controllers for systems governed by matrix-second-order differential equations are obtained by retaining those modes which make the largest contributions to quadratic control objectives. Such contributions, expressed in terms of modal data, used as mode truncation criteria, allow the statement of the specific control objectives to influence the early model reduction from very high order models which are available, for example, from finite element methods. The relative importance of damping, frequency, and eigenvector in the mode truncation decisions are made explicit for each of these control objectives: attitude control, vibration suppression and figure control. The paper also shows that using modal cost analysis (MCA) on the closed loop modes of the optimally controlled system allows the construction of reduced control policies which feedback only those closed loop modal coordinates which are most critical to the quadratic control performance criterion. In this way, the modes which should be controlled (and hence the modes which must be observable by choice of measurements), are deduced from truncations of the optimal controller.

  9. Matrix factorization method for the Hamiltonian structure of integrable systems

    Indian Academy of Sciences (India)

    S Ghosh; B Talukdar; S Chakraborti

    2003-07-01

    We demonstrate that the process of matrix factorization provides a systematic mathematical method to investigate the Hamiltonian structure of non-linear evolution equations characterized by hereditary operators with Nijenhuis property.

  10. Experimental results for improving the matrix condition using a hybrid optical system.

    Science.gov (United States)

    Klapp, Iftach; Mendlovic, David

    2012-03-01

    We present preliminary experimental results for implementing the "blurred trajectories" method on three parallel optics (PO) systems. The "main" system and "auxiliary" optics were simple laboratory graded lenses attached to an iris diaphragm. When applying the blurred trajectories method we first show an improvement in the matrix condition, as the matrix condition number decreased in a range of factors of 3 to 418 relative to the main system. Following that, image restoration by weak regularization was performed so that the system matrix condition dominated the restoration process. It was shown that the restoration results of the PO are better than those of the main system and the auxiliary optics separately. In addition, the quality of the restoration follows the system's matrix condition. The improvement in the matrix condition achieved by the PO system improved the immunity to detection noise. Finally, a comparison to Wiener filtering restoration shows that it is also generally inferior to the proposed method.

  11. Dry arthroscopy with a retraction system for matrix-aided cartilage repair of patellar lesions.

    Science.gov (United States)

    Sadlik, Boguslaw; Wiewiorski, Martin

    2014-02-01

    Several commercially available cartilage repair techniques use a natural or synthetic matrix to aid cartilage regeneration (e.g., autologous matrix-induced chondrogenesis or matrix-induced cartilage implantation). However, the use of matrix-aided techniques during conventional knee joint arthroscopy under continuous irrigation is challenging. Insertion and fixation of the matrix can be complicated by the presence of fluid and the confined patellofemoral joint space with limited access to the lesion. To overcome these issues, we developed a novel arthroscopic approach for matrix-aided cartilage repair of patellar lesions. This technical note describes the use of dry arthroscopy assisted by a minimally invasive retraction system. An autologous matrix-induced chondrogenesis procedure is used to illustrate this novel approach.

  12. An elementary formula for computing shape derivatives of EFIE system matrix

    OpenAIRE

    Kataja, Juhani; Toivanen, Jukka I.

    2012-01-01

    We derive analytical shape derivative formulas of the system matrix representing electric field integral equation discretized with Raviart-Thomas basis functions. The arising integrals are easy to compute with similar methods as the entries of the original system matrix. The results are compared to derivatives computed with automatic differentiation technique and finite differences, and are found to be in excellent agreement.

  13. Effects of spray-drying on w/o/w multiple emulsions prepared from a stearic acid matrix

    Directory of Open Access Journals (Sweden)

    Mlalila N

    2014-12-01

    Full Text Available Nichrous Mlalila,1 Hulda Swai,2 Lonji Kalombo,2 Askwar Hilonga3 1School of Life Sciences and Bioengineering, Nelson Mandela African Institution of Science and Technology, Arusha, Tanzania; 2Materials Science and Manufacturing, Council for Scientific and Industrial Research, Pretoria, South Africa; 3Department of Materials Science and Engineering, Nelson Mandela African Institution of Science and Technology, Arusha, Tanzania Abstract: The goal of this study was to explore the effects of spray-drying on w/o/w double emulsions of methyltestosterone (MT loaded in a stearic acid matrix. MT-loaded nanoparticles were formulated by a water-in-oil-in-water emulsion technique using 50, 75, and 100 mg of stearic acid, 2% and 3% w/v polyvinyl alcohol, 5% w/v lactose, and 0.2% w/v chitosan. The emulsions were immediately spray-dried based on an optimized model of inlet temperature and pump rate, and characterized for optimized responses with regard to particle size, polydispersity index, and zeta potential, for both emulsion and powder samples. Dynamic light scattering analysis shown that the nanoparticles increased in size with increasing concentrations of polyvinyl alcohol and stearic acid. Scanning electron microscopy indicated that the MT-loaded nanoparticles were spherical in shape, had a smooth surface, and were in an amorphous state, which was confirmed by differential scanning calorimetry. These MT-loaded nanoparticles are a promising candidate carrier for the delivery of MT; however, further studies are needed in order to establish the stability of the system and the cargo release profile under normal conditions of use. Keywords: double emulsions, nanoparticles, pump rate, spray-drying, testosterone

  14. Inhibition of matrix metalloproteinases expression in human dental pulp cells by all-trans retinoic acid

    Institute of Scientific and Technical Information of China (English)

    Jin Man Kim; Sang Wook Kang; Su-Mi Shin; Duck Su Kim; Kyong-Kyu Choi; Eun-Cheol Kim; Sun-Young Kim

    2014-01-01

    All-trans retinoic acid (ATRA) inhibits matrix metalloproteinase (MMP)-2 and MMP-9 in synovial fibroblasts, skin fibroblasts, bronchoalveolar lavage cells and cancer cells, but activates MMP-9 in neuroblast and leukemia cells. Very little is known regarding whether ATRA can activate or inhibit MMPs in human dental pulp cells (HDPCs). The purpose of this study was to determine the effects of ATRA on the production and secretion of MMP-2 and-9 in HDPCs. The productions and messenger RNA (mRNA) expressions of MMP-2 and-9 were accessed by gelatin zymography and real-time polymerase chain reaction (PCR), respectively. ATRA was found to decrease MMP-2 level in a dose-dependent manner. Significant reduction in MMP-2 mRNA expression was also observed in HDPCs treated with 25 mmol?L21 ATRA. However, HDPCs treated with ATRA had no effect on the pattern of MMP-9 produced or secreted in either cell extracts or conditioned medium fractions. Taken together, ATRA had an inhibitory effect on MMP-2 expression in HDPCs, which suggests that ATRA could be a candidate as a medicament which could control the inflammation of pulp tissue in vital pulp therapy and regenerative endodontics.

  15. Electrochemical biosensing platform using hydrogel prepared from ferrocene modified amino acid as highly efficient immobilization matrix.

    Science.gov (United States)

    Qu, Fengli; Zhang, Yi; Rasooly, Avraham; Yang, Minghui

    2014-01-21

    To increase the loading of glucose oxidase (GOx) and simplify glucose biosensor fabrication, hydrogel prepared from ferrocene (Fc) modified amino acid phenylalanine (Phe, F) was utilized for the incorporation of GOx. The synthesized hydrogel displays good biocompatibility and contains a significant number of Fc moieties, which can be considered as an ideal matrix to immobilize enzymes for the preparation of mediator-based biosensors. The hydrogel was studied by scanning electron microscopy, which indicated that it was composed of nanofibers with a diameter of around 50-100 nm and length extended to 1 mm. With the addition of GOx into the hydrogel and by directly dropping the resulting biocomposite onto the electrode surface, a glucose biosensor, that displays good performance due to improved enzyme loading and efficient electron transfer, can be simply constructed. The favorable network structure and good biocompatibility of the hydrogel could effectively avoid enzyme leakage and maintain the bioactivity of the enzymes, which resulted in good stability of the biosensor. The biosensor was utilized for the detection of glucose in blood samples with results comparable to those obtained from the hospital. The hydrogel as a functional component of an amperometric biosensor has implications for future development of biosensors and for clinical applications. PMID:24383679

  16. Study of acid solution bonding in epoxy matrix for sealed radioactive sources production

    International Nuclear Information System (INIS)

    The present work aims to analyze different resin formulations. These formulations are used in the production of radioactive sealed sources that are used in many fields such as nuclear medicine; environmental analyzes, radiation detectors accuracy check, and so on. These sources can be produced with different radioisotopes and different activities, it all depending on the use they will have. Certain types of resins have the same density water. This property is appreciated when we consider that radiotracers used in nuclear medicine are applied in aqueous solutions. So the sources used for checking and calibrating equipment must have their radioisotopes sealed in a material having similar properties, thus the measures are reproducible and repetitive. The most important aspect that is brought to attention in this work is the miscibility those resins have with water. The radioisotopes for the production of the sources are supplied in an aqueous form. In case the resin and the radioisotope solution do not mix, the source will not be sturdy enough to seal the radioisotopes in its structure and the source will not be safe. There were prepared different formulations with different amounts of acid solution, and the cured formulations were analyzed by Wipe Test, DSC (Differential Splanatory Calorimetry) and also, the possible volatile aspect of the radionuclide used. All to evaluate the integrity of the sources. The obtained results were satisfactory and show that when the resin is well cured, the radioisotope remains sealed in the matrix, making it possible to produce radioactive sealed sources. (author)

  17. Fluorescence Excitation-Emission Matrix Characterization of a Commercial Humic Acid

    Institute of Scientific and Technical Information of China (English)

    傅平青; 吴丰昌; 刘丛强

    2004-01-01

    Excitation-emission matrix fluorescence spectroscopy (EEM) has been widely used to elucidate the origin and structure of humic substances in natural environments. Due to its high sensitivity, good selectivity and non-destructive advantage, the EEM was applied to characterizing a commercial Fluka humic acid (FHA). The results showed that the EEMs of FHA has several Ex/Em peaks. Ionic strength (0-0.05 mol/L KClO-4) exerted little effect on the fluorescence properties of FHA, while the concentrations (5-100 mg/L) of FHA and pH (2-12) had significant effects. A red shift in the longer wavelength peak region was observed when the concentrations or pH values increased. The fluorescence intensity increased with increasing pH, but slightly decreased in the case of pH=5.0. The protonation constants (lgK'-HL) of peak B were calculated to be 3.57 and 3.13, indicating that peak B was due to carboxyl groups. The r-(A/B) values range from 0.61 to 2.59. A strong linear relationship between r-(A/B) and pH was also observed. This indicates that the fluorescence peaks A and B posses similar inherent fluorescence characteristics.

  18. Study of acid solution bonding in epoxy matrix for sealed radioactive sources production

    Energy Technology Data Exchange (ETDEWEB)

    Benega, Marcos A.G.; Nagatomi, Helio R.; Rostelato, Maria Elisa C.M.; Tiezzi, Rodrigo; Rodrigues, Bruna T.; Peleias Junior, Fernando; Souza, Carla D.; Souza, Daiane C.C. de; Souza, Anderson S. de; Silva, Thais H. da, E-mail: carladdsouza@yahoo.com.br, E-mail: marcosagbenega@gmail.com, E-mail: hrnagato@ipen.br, E-mail: elisaros@ipen.br, E-mail: rktiezzi@gmail.com, E-mail: bteigarodrigues@gmail.com, E-mail: fernandopeleias@gmail.com, E-mail: dcsouza@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2014-07-01

    The present work aims to analyze different resin formulations. These formulations are used in the production of radioactive sealed sources that are used in many fields such as nuclear medicine; environmental analyzes, radiation detectors accuracy check, and so on. These sources can be produced with different radioisotopes and different activities, it all depending on the use they will have. Certain types of resins have the same density water. This property is appreciated when we consider that radiotracers used in nuclear medicine are applied in aqueous solutions. So the sources used for checking and calibrating equipment must have their radioisotopes sealed in a material having similar properties, thus the measures are reproducible and repetitive. The most important aspect that is brought to attention in this work is the miscibility those resins have with water. The radioisotopes for the production of the sources are supplied in an aqueous form. In case the resin and the radioisotope solution do not mix, the source will not be sturdy enough to seal the radioisotopes in its structure and the source will not be safe. There were prepared different formulations with different amounts of acid solution, and the cured formulations were analyzed by Wipe Test, DSC (Differential Splanatory Calorimetry) and also, the possible volatile aspect of the radionuclide used. All to evaluate the integrity of the sources. The obtained results were satisfactory and show that when the resin is well cured, the radioisotope remains sealed in the matrix, making it possible to produce radioactive sealed sources. (author)

  19. Hydrophobic silica nanoparticles as reinforcing filler for poly (lactic acid polymer matrix

    Directory of Open Access Journals (Sweden)

    Pilić Branka M.

    2016-01-01

    Full Text Available Properties of poly (lactic acid (PLA and its nanocomposites, with silica nanoparticles (SiO2, as filler were investigated. Neat PLA films and PLA films with different percentage of hydrophobic fumed silica nanoparticles (0.2, 0.5, 1, 2, 3 and 5 wt. % were prepared by solution casting method. Several tools were used to characterize the influence of different silica content on crystalline behavior, and thermal, mechanical and barrier properties of PLA/SiO2 nanocomposites. Results from scanning electron microscope (SEM showed that the nanocomposite preparation and selection of specific hydrophobic spherical nano filler provide a good dispersion of the silica nanoparticles in the PLA matrix. Addition of silica nanoparticles improved mechanical properties, the most significant improvement being observed for lowest silica content (0.2wt.%. Barrier properties were improved for all measured gases at all loadings of silica nanoparticles. The degree of crystallinity for PLA slightly increased by adding 0.2 and 0.5 wt. % of nano filler. [Projekat Ministarstva nauke Republike Srbije, br. III46001

  20. Alteration of nuclear matrix-intermediate filament system and differential expression of nuclear matrix proteins during human hepatocarcinoma cell differentiation

    Institute of Scientific and Technical Information of China (English)

    Jian Tang; Jing-Wen Niu; Dong-Hui Xu; Zhi-Xing Li; Qi-Fu Li; Jin-An Chen

    2007-01-01

    accompanied by the configurational changes of nuclear matrix-intermediate filament (NM-IF)system and the compositional changes of nuclear matrix protein expression. These changes may be important morphological or functional indications of the cancer cell reversion.

  1. Matrix effect on serum uric acid determination%血清尿酸测定的基质效应

    Institute of Scientific and Technical Information of China (English)

    张江涛; 王冬环; 张传宝; 曾洁; 马嵘; 赵海舰; 周伟燕; 张天娇; 闫颖; 胡翠华; 汪静

    2016-01-01

    Objective To evaluate the matrix effect of 21 samples (sera and processed materials) on 13 routine determination systems in serum uric acid determination. Methods Determinations were performed according to the health industry standard WS/T356-2011. Isotope dilution liquid chromatography tandem mass spectrometry (ID-LC/MS/MS)was used as comparison method,and 13 kinds of uric acid kits(enzymic assay) were chosen as evaluation method with HITACHI 7180 analyzer. The 21 samples included 4 calibrators,5 kinds of external quality assessment(EQA) samples,6 kinds of quality control materials,3 processed materials (1 kind of spine serum and 2 kinds of liquid solutions),1 kind of standard reference material(SRM) 909c from the National Institute of Standards and Technology (NIST)and 2 kinds of the External Quality Assessment Scheme for Reference Laboratories in Laboratory Medicine (RELA)samples from the International Federation of Clinical Chemistry and Laboratory Medicine(IFCC). A total of 40 fresh frozen sera and the 21 samples were analyzed by comparison method and evaluation method. The results obtained by the 2 methods were analyzed by linear regression analysis. Two-tailed 95% confidence intervals for Y predictive value were computed,and the matrix effect of sera and processed materials was evaluated. Results A total of 5 kinds of evaluation samples (2 EQA samples,1 SRM 909c and 2 RELA samples)from fresh or lyophilized sera showed no matrix effect in all routine methods. Two calibrators (Landau and Dirui) showed matrix effect in 1 routine method. Of 5 EQA samples,except for fresh sera used for trueness verification,other lyophilized sera showed matrix effect in most routine methods. The 4 of 6 quality control materials showed no matrix effect,and 2 quality control materials with high values showed negative matrix effect. Conclusions Fresh serum is a reliable sample and could be used in SRM and quality control material preparation and EQA. Some calibrators could

  2. Neuro-fuzzy Logic Control of Single Phase Matrix Converter Fed Induction Heating System

    Directory of Open Access Journals (Sweden)

    P. Umasankar

    2015-02-01

    Full Text Available This study presents a design and simulation of Neuro-Fuzzy Logic Controlled (NFLC Single Phase Matrix Converter (SPMC fed Induction Heating (IH system. Single phase matrix converter system is an AC-AC converter which eliminates the usage of reactive storage elements and its performance over varying operating frequencies can be controlled by varying the Pulse Width Modulation (PWM signal fed to the switches of single phase matrix converter. In the existing system a Fuzzy Logic Controller (FLC was designed to control the matrix converter which yielded low Total Harmonic Distortion (THD values when compared to previous systems. In this study a Neuro-Fuzzy Logic Controller was designed to control the single phase matrix converter and the results obtained prove its advantage over the existing Fuzzy Logic based control system.

  3. Structure of isothiocyanic acid dimers. Theoretical and FTIR matrix isolation studies

    Science.gov (United States)

    Krupa, Justyna; Wierzejewska, Maria

    2016-05-01

    A quantum mechanical study of the potential energy surface for the HNCS dimer is reported. The calculations were performed using DFT and ab initio MP2 methods. The most stable is a cyclic form with a double N-H⋯S interaction and the interaction energy in the range of 16.91-18.92 kJ mol-1. An open HNCS dimer bound by the N-H⋯N hydrogen bond is by ca 3.3-5.1 kJ mol-1 less stable. Experimental FTIR matrix isolation studies of HNCS/N2 system show that exclusively less stable open dimer is formed in solid nitrogen. Possible reasons for the observed discrepancy between theory and experiment are discussed.

  4. On the Formulation of Flexible Multibody Systems with Constant Mass Matrix

    DEFF Research Database (Denmark)

    Pedersen, Niels Leergaard

    1997-01-01

    A flexible body in a multibody system isdescribed only by the position of the nodes in theinertial frame. With this description we can formulatethe mass matrix of the flexible multibody as aconstant matrix. This matrix can be inverted in apreprocessing stage which yields a more efficientaccelerat...... of this formulation is that neither thecentrifugal nor the Coriolis forces appear in theequations due to the description of the flexible body....

  5. Solution of the Lyapunov matrix equation for a system with a time-dependent stiffness matrix

    DEFF Research Database (Denmark)

    Pommer, Christian; Kliem, Wolfhard

    2004-01-01

    The stability of the linearized model of a rotor system with non-symmetric strain and axial loads is investigated. Since we are using a fixed reference system, the differential equations have the advantage to be free of Coriolis and centrifugal forces. A disadvantage is nevertheless the occurrence...

  6. Topological, smooth and holomorphic classifications of nonautonomous linear differential systems and projective matrix Riccati equations

    CERN Document Server

    Gorbuzov, V N

    2011-01-01

    The questions of global topological, smooth and holomorphic classifications of the differential systems, defined by covering foliations, are considered. The received results are applied to nonautonomous linear differential systems and projective matrix Riccati equations.

  7. Initial guidance on digraph-matrix analysis for systems interaction studies. [PWR; BWR

    Energy Technology Data Exchange (ETDEWEB)

    Alesso, H.P.; Sacks, I.J.; Smith, C.F.

    1983-03-01

    This report describes the digraph-matrix analysis for systems structural analysis. The method is useful to analysts that are searching for both single failures and paired failures that disable systems. The digraph-matrix analysis can assure the analyst that the independent functioning of a safety system is not jeopardized by design features that cause faults to be dependent. The digraph-matrix analysis facilitates the discovery and the quantification of component reachability. The guidance is sufficiently specific that the reader can make direct application. Because a systems interaction analysis of an LWR is expensive, the resource efficiency of a candidate method is important to the staff. A demonstration of the digraph-matrix analysis is part of the staffs efforts to provide a measure of its resource efficiency. Additionally, there are features within the digraph-matrix analysis itself that might be modified to enhance resource efficiency.

  8. Iterative reconstruction using a Monte Carlo based system transfer matrix for dedicated breast positron emission tomography.

    Science.gov (United States)

    Saha, Krishnendu; Straus, Kenneth J; Chen, Yu; Glick, Stephen J

    2014-08-28

    To maximize sensitivity, it is desirable that ring Positron Emission Tomography (PET) systems dedicated for imaging the breast have a small bore. Unfortunately, due to parallax error this causes substantial degradation in spatial resolution for objects near the periphery of the breast. In this work, a framework for computing and incorporating an accurate system matrix into iterative reconstruction is presented in an effort to reduce spatial resolution degradation towards the periphery of the breast. The GATE Monte Carlo Simulation software was utilized to accurately model the system matrix for a breast PET system. A strategy for increasing the count statistics in the system matrix computation and for reducing the system element storage space was used by calculating only a subset of matrix elements and then estimating the rest of the elements by using the geometric symmetry of the cylindrical scanner. To implement this strategy, polar voxel basis functions were used to represent the object, resulting in a block-circulant system matrix. Simulation studies using a breast PET scanner model with ring geometry demonstrated improved contrast at 45% reduced noise level and 1.5 to 3 times resolution performance improvement when compared to MLEM reconstruction using a simple line-integral model. The GATE based system matrix reconstruction technique promises to improve resolution and noise performance and reduce image distortion at FOV periphery compared to line-integral based system matrix reconstruction.

  9. Effects of ultraviolet irradiation on bonding strength between Co-Cr alloy and citric acid-crosslinked gelatin matrix.

    Science.gov (United States)

    Inoue, Motoki; Sasaki, Makoto; Katada, Yasuyuki; Taguchi, Tetsushi

    2014-02-01

    Novel techniques for creating a strong bond between polymeric matrices and biometals are required. We immobilized polymeric matrices on the surface of biometal for drug-eluting stents through covalent bond. We performed to improve the bonding strength between a cobalt-chromium alloy and a citric acid-crosslinked gelatin matrix by ultraviolet irradiation on the surface of cobalt-chromium alloy. The ultraviolet irradiation effectively generated hydroxyl groups on the surface of the alloy. The bonding strength between the gelatin matrix and the alloy before ultraviolet irradiation was 0.38 ± 0.02 MPa, whereas it increased to 0.48 ± 0.02 MPa after ultraviolet irradiation. Surface analysis showed that the citric acid derivatives occurred on the surface of the cobalt-chromium alloy through ester bond. Therefore, ester bond formation between the citric acid derivatives active esters and the hydroxyl groups on the cobalt-chromium alloy contributed to the enhanced bonding strength. Ultraviolet irradiation and subsequent immobilization of a gelatin matrix using citric acid derivatives is thus an effective way to functionalize biometal surfaces.

  10. Protective effect of naringin on 3-nitropropionic acid-induced neurodegeneration through the modulation of matrix metalloproteinases and glial fibrillary acidic protein.

    Science.gov (United States)

    Gopinath, Kulasekaran; Sudhandiran, Ganapasam

    2016-01-01

    Naringin (4',5,7-trihydroxy-flavonone-7-rhamnoglucoside), a flavonone present in grapefruit, has recently been reported to protect against neurodegeration, induced with 3-nitropropionic acid (3-NP), through its antioxidant, anti-inflammatory, and antiapoptotic properties. This study used a rat model of 3-NP-induced neurodegeneration to investigate the neuroprotective effects of naringin exerted by modulating the expression of matrix metalloproteinases and glial fibrillary acidic protein. Neurodegeneration was induced with 3-NP (10 mg/kg body mass, by intraperitoneal injection) once a day for 2 weeks, and induced rats were treated with naringin (80 mg/kg body mass, by oral gavage, once a day for 2 weeks). Naringin ameliorated the motor abnormalities caused by 3-NP, and reduced blood-brain barrier dysfunction by decreasing the expression of matrix metalloproteinases 2 and 9, along with increasing the expression of the tissue inhibitors of metalloproteinases 1 and 2 in 3-NP-induced rats. Further, naringin reduced 3-NP-induced neuroinflammation by decreasing the expression of nuclear factor-kappa B and glial fibrillary acidic protein. Thus, naringin exerts protective effects against 3-NP-induced neurodegeneration by ameliorating the expressions of matrix metalloproteinases and glial fibrillary acidic protein. PMID:26544788

  11. On Optimal Backward Perturbation Analysis for the Linear System with Skew Circulant Coefficient Matrix

    Science.gov (United States)

    Jiang, Zhaolin; Shen, Nuo; Zhou, Jianwei

    2013-01-01

    We first give the style spectral decomposition of a special skew circulant matrix C and then get the style decomposition of arbitrary skew circulant matrix by making use of the Kronecker products between the elements of first row in skew circulant and the special skew circulant C. Besides that, we obtain the singular value of skew circulant matrix as well. Finally, we deal with the optimal backward perturbation analysis for the linear system with skew circulant coefficient matrix on the base of its style spectral decomposition. PMID:24369488

  12. Delivery of Polyunsaturated Fatty Acids from a Glycerol Polyester Matrix with Anti-oxidant Properties

    Science.gov (United States)

    Awareness of the health benefits associated with the polyunsaturated acids such as alpha linolenic (ALA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA), has generated interest in formulating foods and dietary supplements with these compounds. However, the highly unsaturated structure o...

  13. Simulating local measurements on a quantum many-body system with stochastic matrix product states

    DEFF Research Database (Denmark)

    Gammelmark, Søren; Mølmer, Klaus

    2010-01-01

    We demonstrate how to simulate both discrete and continuous stochastic evolutions of a quantum many-body system subject to measurements using matrix product states. A particular, but generally applicable, measurement model is analyzed and a simple representation in terms of matrix product operators...

  14. Downregulation of membrane type-matrix metalloproteinases in the inflamed or injured central nervous system

    DEFF Research Database (Denmark)

    Toft-Hansen, Henrik; Babcock, Alicia A; Millward, Jason M;

    2007-01-01

    BACKGROUND: Matrix metalloproteinases (MMPs) are thought to mediate cellular infiltration in central nervous system (CNS) inflammation by cleaving extracellular matrix proteins associated with the blood-brain barrier. The family of MMPs includes 23 proteinases, including six membrane type-MMPs (MT...

  15. The Minimum Cut Sets of System Fault Based on Oriented Matrix Analysis

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    In this paper, the oriented matrix analysis (OMA) method of system reliability has been discussed. OMA uses a oriented fault graph instead of a traditional fault tree model. By defining the specific logic operation and calculating a reachability matrix, the cut sets can be formed directly and the minimum cut sets can be easily obtained.

  16. Molecular surface area based predictive models for the adsorption and diffusion of disperse dyes in polylactic acid matrix.

    Science.gov (United States)

    Xu, Suxin; Chen, Jiangang; Wang, Bijia; Yang, Yiqi

    2015-11-15

    Two predictive models were presented for the adsorption affinities and diffusion coefficients of disperse dyes in polylactic acid matrix. Quantitative structure-sorption behavior relationship would not only provide insights into sorption process, but also enable rational engineering for desired properties. The thermodynamic and kinetic parameters for three disperse dyes were measured. The predictive model for adsorption affinity was based on two linear relationships derived by interpreting the experimental measurements with molecular structural parameters and compensation effect: ΔH° vs. dye size and ΔS° vs. ΔH°. Similarly, the predictive model for diffusion coefficient was based on two derived linear relationships: activation energy of diffusion vs. dye size and logarithm of pre-exponential factor vs. activation energy of diffusion. The only required parameters for both models are temperature and solvent accessible surface area of the dye molecule. These two predictive models were validated by testing the adsorption and diffusion properties of new disperse dyes. The models offer fairly good predictive ability. The linkage between structural parameter of disperse dyes and sorption behaviors might be generalized and extended to other similar polymer-penetrant systems.

  17. Fuzzy Logic Control of Single Phase Matrix Converter Fed Induction Heating System

    OpenAIRE

    P. Umasankar; Dr.S.Senthilkumar

    2014-01-01

    This article represents the modeling and simulation of a Single Phase Matrix Converter (SPMC) fed Induction Heating (IH) system. The working principle and the control system using Fuzzy Logic Controller (FLC) are elucidated in detail. The performance of the system and their harmonic content analysis of Single Phase Matrix Converter are carried out in MATLAB/Simulink environment. Pulse Width Modulation (PWM) switching strategy by varying the duty cycle based on Fuzzy Logic Control is employed ...

  18. 21 CFR 862.1450 - Lactic acid test system.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Lactic acid test system. 862.1450 Section 862.1450....1450 Lactic acid test system. (a) Identification. A lactic acid test system is a device intended to measure lactic acid in whole blood and plasma. Lactic acid measurements that evaluate the acid-base...

  19. Wnt/β-Catenin and Retinoic Acid Receptor Signaling Pathways Interact to Regulate Chondrocyte Function and Matrix Turnover*

    OpenAIRE

    Yasuhara, Rika; Yuasa, Takahito; Williams, Julie A.; Byers, Stephen W.; Shah, Salim; Pacifici, Maurizio; Iwamoto, Masahiro; Enomoto-Iwamoto, Motomi

    2009-01-01

    Activation of the Wnt/β-catenin and retinoid signaling pathways is known to tilt cartilage matrix homeostasis toward catabolism. Here, we investigated possible interactions between these pathways. We found that all-trans-retinoic acid (RA) treatment of mouse epiphyseal chondrocytes in culture did increase Wnt/β-catenin signaling in the absence or presence of exogenous Wnt3a, as revealed by lymphoid enhancer factor/T-cell factor/β-catenin reporter activity and β-catenin nuclear accumulation. T...

  20. Synthesis of silica coated zinc oxide–poly(ethylene-co-acrylic acid) matrix and its UV shielding evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Ramasamy, Mohankandhasamy [Division of Bionanotechnology, Gachon University, Seongnam 461-701 (Korea, Republic of); Kim, Yu Jun; Gao, Haiyan [Department of Polymer Engineering, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Yi, Dong Kee, E-mail: vitalis@mju.ac.kr [Department of Chemistry, Myongji University, Yongin 449-728 (Korea, Republic of); An, Jeong Ho, E-mail: jhahn1us@skku.edu [Department of Polymer Engineering, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of)

    2014-03-01

    Graphical abstract: - Highlights: • Well layer thickness controlled silica shell was made on ZnO nanoparticles. • PEAA, an interfacial agent is used to make nanocomposite–polymer matrix by twin-screw extruder. • Si-ZnO/PEAA matrix is highly stable and UV protective as compared to ZnO/PEAA matrix. • Nanoparticle embedded polymer matrix is suggested to make UV shielding fabrics with Nylon4. - Abstract: Silica coated zinc oxide nanoparticles (Si-ZnO NPs) (7 nm thick) were synthesized successfully and melt blended with poly(ethylene-co-acrylic acid) (PEAA resin) to improving ultraviolet (UV) shielding of zinc oxide nanoparticles (ZnO NPs). The photostability of both the ZnO NPs and Si-ZnO NPs were analyzed by the difference in photoluminescence (PL) and by methylene blue (MB) degradation. Photo-degradation studies confirmed that Si-ZnO NPs are highly photostable compared to ZnO NPs. The melt blended matrices were characterized by field emission scanning electron microscopy interfaced with energy dispersive X-ray spectroscopy (FE-SEM-EDX). The UV shielding property was analyzed from the transmittance spectra of UV–visible (UV–vis) spectroscopy. The results confirmed fine dispersion of thick Si-ZnO NPs in the entire resin matrix. Moreover, the Si-ZnO/PEAA showed about 97% UV shielding properties than the ZnO/PEAA.

  1. Automated MALDI Matrix Coating System for Multiple Tissue Samples for Imaging Mass Spectrometry

    Science.gov (United States)

    Mounfield, William P.; Garrett, Timothy J.

    2012-03-01

    Uniform matrix deposition on tissue samples for matrix-assisted laser desorption/ionization (MALDI) is key for reproducible analyte ion signals. Current methods often result in nonhomogenous matrix deposition, and take time and effort to produce acceptable ion signals. Here we describe a fully-automated method for matrix deposition using an enclosed spray chamber and spray nozzle for matrix solution delivery. A commercial air-atomizing spray nozzle was modified and combined with solenoid controlled valves and a Programmable Logic Controller (PLC) to control and deliver the matrix solution. A spray chamber was employed to contain the nozzle, sample, and atomized matrix solution stream, and to prevent any interference from outside conditions as well as allow complete control of the sample environment. A gravity cup was filled with MALDI matrix solutions, including DHB in chloroform/methanol (50:50) at concentrations up to 60 mg/mL. Various samples (including rat brain tissue sections) were prepared using two deposition methods (spray chamber, inkjet). A linear ion trap equipped with an intermediate-pressure MALDI source was used for analyses. Optical microscopic examination showed a uniform coating of matrix crystals across the sample. Overall, the mass spectral images gathered from tissues coated using the spray chamber system were of better quality and more reproducible than from tissue specimens prepared by the inkjet deposition method.

  2. Matrix Cracking in Four Different 2D SiC/SiC Composite Systems

    Science.gov (United States)

    Morscher, Gregory N.

    2003-01-01

    Silicon carbide fiber reinforced, silicon carbide matrix composites are some of the most advanced composite systems for high-temperature, high-stress applications in oxidizing environments. A basic area that needs to be understood for the purpose of material behavior modeling and optimization is the architectural, constituent, and mechanistic factors that contribute to non-linear stress-strain behavior. The mechanism that causes non-linear stress-strain in dense-matrix composites is the formation and propagation of bridged matrix cracks. In addition, the occurrence and propagation of matrix cracks controls the time-dependent strength-properties of these materials in oxidizing environments at elevated temperatures. A modal acoustic emission technique has been used to monitor and estimate the stress-dependent matrix cracking. Two different SiC matrix systems, chemical vapor infiltrated (CVI) and melt-infiltrated (MI), with two different SiC fiber reinforcement, Hi-Nicalon (trademark) and Sylramic (trademark) were compared. Even though the averages of the range where matrix cracking occurred for the composites varied by more than 0.1% in strain and almost 200 MPa in stress, the range or distribution for matrix cracking could be reduced to a narrow band of stress for CVI SiC and MI SiC composites if it were assumed that all matrix cracks emanate outside of the load-bearing fiber, interphase, CVI preform minicomposite. A simple relationship was determined to describe stress-dependent matrix cracking which can then be used to estimate the onset of large, bridged matrix cracks or for material behavior models.

  3. Fuzzy Logic based Light Load Efficiency Improvement of Matrix Converter Based Wind Generation System

    OpenAIRE

    Vinod Kumar; R.R. Joshi

    2007-01-01

    The paper describes a variable speed wind generation system where fuzzy logic principles are used for light load efficiency improvement and optimization. A squirrel cage induction generator feeds the power to an improved topology of matrix converter which pumps power to a utility grid or can supply to an autonomous system. The power factor at the interface with the grid is controlled by the matrix converter to ensure purely active power injection into the grid for optimal utilization of the ...

  4. Rotor Bearing System Analysis Using the Transfer Matrix Method with Thickness Assumption of Disk and Bearing

    OpenAIRE

    Ghasemalizadeh, Omid; Mirzaee, Mohammad Reza; Sadeghi, Hossein; Ahmadian, Mohammad Taghi

    2013-01-01

    One of the methods to find the natural frequencies of rotating systems is the application of the transfer matrix method. In this method the rotor is modeled as several elements along the shaft which have their own mass and moment of inertia. Using these elements, the entire continuous system is discretized and the corresponding differential equation can be stated in matrix form. The bearings at the end of the shaft are modeled as equivalent spring and dampers which are applied as boundary con...

  5. Radiation-induced transformations of matrix-isolated formic acid: evidence for the HCOOH → HOCO + H channel.

    Science.gov (United States)

    Ryazantsev, Sergey V; Feldman, Vladimir I

    2015-11-11

    The effect of X-ray irradiation on the isolated formic acid molecules (HCOOH) in solid noble gas matrices (Xe, Kr, Ar, and Ne) at very low temperatures (6 K) was first studied by FTIR spectroscopy. Carbon oxides (CO and CO2) and hydrocarboxyl radicals (HOCO) have been detected as the principal degradation products. The formation of HOCO radicals represents a primary dissociation channel for formic acid, which was not reported previously under UV photolysis in solids. This reaction can be explained by the involvement of the recombination-induced excited states, which are not populated in photolysis. The effects of the matrix and the absorbed dose on the product formation were studied in detail and possible mechanisms are discussed with particular attention to the difference between radiolysis and UV-photolysis of the matrix-isolated formic acid. The results obtained provide a new insight into the effects of high-energy impact on the simplest carboxylic acid with possible implications to the astrochemical problems, in particular, the prebiotic evolution in the interstellar medium. PMID:26524429

  6. Electrochemical sensor for dopamine based on imprinted silica matrix-poly(aniline boronic acid) hybrid as recognition element.

    Science.gov (United States)

    Li, Jian; Zhang, Ning; Sun, Qingqing; Bai, Zhanming; Zheng, Jianbin

    2016-10-01

    A novel imprinted silica matrix-poly(aniline boronic acid) hybrid for electrochemical detection of dopamine (DA) was developed. Boronic acid functionalized conducting polymer was electrochemically prepared on Au electrode. The number of covalent binding sites toward DA templates was controlled by potential cycles. A precursory sol solution of ammonium fluorosilicate (as cross-linking monomer) containing DA was spin-coated on the polymer modified electrode. Under NH3 atmosphere, the hydroxyl ions were generated in the solution and catalyzed the hydrolysis of fluorosilicate to form silica matrix. After this aqueous sol-gel process, an inorganic framework around the DA template was formed and the imprinted hybrid for DA was also produced. As revealed by scanning electron microscopy, UV-vis spectroscopy and cyclic voltammetry characterization, DA was embedded in the imprinted hybrid successfully. The affinity and selectivity of the imprinted hybrid were also characterized by cyclic voltammetry. The imprinted hybrid showed higher affinity for DA than that for epinephrine, and little or no affinity for ascorbic acid and uric acid due to the combined effects of covalent interaction, cavities matching and electrostatic repulsion. The imprinted hybrid sensor exhibited a quick response (within 5min) to DA in the concentration range from 0.05 to 500μmolL(-1) with a detection limit of 0.018μmolL(-1). The prepared sensor was also applied to detect DA in real samples with a satisfactory result. PMID:27474321

  7. ANALYSIS OF TWO-MACHINE CONWIP SYSTEM:MATRIX GEOMETRIC SOLUTION

    Institute of Scientific and Technical Information of China (English)

    LIU Bin; YUE Dequan; CAO Jinhua; WANG Huanqiu

    2000-01-01

    In this paper we consider a two-machine CONWIP system. Firstly, we mathematically model the system as a QBD process. By using the matrix geometric solution technique, we obtain the equilibrium conditions of the system. Next, we derive the stationary probability distribution of the process. Finally, we give some important performance measures of the system.

  8. Matrix isolation infrared spectra of O-H· · · π Hydrogen bonded complexes of Acetic acid and Trifluoroacetic acid with Benzene

    Indian Academy of Sciences (India)

    PUJARINI BANERJEE; INDRANI BHATTACHARYA; TAPAS CHAKRABORTY

    2016-10-01

    Mid infrared spectra of two O–H· · · π hydrogen-bonded binary complexes of acetic acid (AA) and trifluoroacetic acid (F₃AA) with benzene (Bz) have been measured by isolating the complexes in an argon matrix at ∼8 K. In a matrix isolation condition, the O–H stretching fundamentals (νO−H) of the carboxylic acid groups of the two molecules are observed to have almost the same value. However, the spectral red-shifts of νO−H bands of the two acids on complexation with Bz are largely different, 90 and 150 cm⁻¹ for AA and F₃AA, respectively. Thus, the O–H bond weakening of the two acids upon binding with Bz in a non-interacting environment follows the sequence of their ionic dissociation tendencies (pKa) in aqueous media. Furthermore, ΔνO−H of the latter complex is the largest among the known π-hydrogen bonded binary complexes of prototypical O–H donors reported so far with respect to Bz as acceptor. It is also observed that the spectral shifts (ΔνO−H) of phenol-Bz and carboxylic acid-Bz complexes show similar dependence on the acidity factor (pKa). Electronic structure theory has been used to suggest suitable geometries of the complexes that are consistent with the measured IR spectral changes. Calculation at MP2/6-311++G (d, p) level predicts a T-shaped geometry for both AA-Bz and F₃AA-Bz complexes, and the corresponding binding energies are 3.0 and 4.5 kcal/mol, respectively. Natural Bond Orbital (NBO) analysis has been performed to correlate the observed spectral behavior of the complexes with the electronic structure parameters.

  9. Fuzzy Controller for Matrix Converter System to Improve Its Quality of Output

    Directory of Open Access Journals (Sweden)

    N.Mahendran

    2010-10-01

    Full Text Available In this paper, Fuzzy Logic controller is developed for ac/ac Matrix Converter. Furthermore,Total Harmonic Distortion is reduced significantly. Space Vector Algorithm is a method to improve powerquality of the converter output. But its quality is limited to 86.7%.We are introduced a Cross coupled DQaxis controller to improve power quality. The Matrix Converter is an attractive topology for High voltagetransformation ratio. A Matlab / Simulink simulation analysis of the Matrix Converter system is provided.The design and implementation of fuzzy controlled Matrix Converter is described. This AC-AC system isproposed as an effective replacement for the conventional AC-DC-AC system which employs a two-steppower conversion.

  10. Fuzzy Controller for Matrix Converter System to Improve Its Quality of Output

    Directory of Open Access Journals (Sweden)

    N.Mahendran

    2010-10-01

    Full Text Available In this paper, Fuzzy Logic controller is developed for ac/ac Matrix Converter. Furthermore, Total Harmonic Distortion is reduced significantly. Space Vector Algorithm is a method to improve power quality of the converter output. But its quality is limited to 86.7%.We are introduced a Cross coupled DQ axis controller to improve power quality. The Matrix Converter is an attractive topology for High voltage transformation ratio. A Matlab / Simulink simulation analysis of the Matrix Converter system is provided. The design and implementation of fuzzy controlled Matrix Converter is described. This AC-AC system is proposed as an effective replacement for the conventional AC-DC-AC system which employs a two-step power conversion.

  11. Strategies for the elimination of matrix effects in the LC-MS/MS analysis of the lipophilic toxins okadaic acid and azaspiracid-1 in molluscan shellfish

    OpenAIRE

    Kilcoyne, Jane; Fux, Elie

    2010-01-01

    Considerable efforts are being made worldwide to replace in vivo assays with instrumental methods of analysis for the monitoring of marine biotoxins in shellfish. Analysis of these compounds by the preferred technique of LC-MS/MS is challenged by matrix effects associated with shellfish tissue components. In methods validation, assessment of matrix interferences is imperative to ensure the accuracy of analytical results. We evaluated matrix interferences in the analysis of okadaic acid (OA)...

  12. 21 CFR 862.1295 - Folic acid test system.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Folic acid test system. 862.1295 Section 862.1295....1295 Folic acid test system. (a) Identification. A folic acid test system is a device intended to measure the vitamin folic acid in plasma and serum. Folic acid measurements are used in the diagnosis...

  13. MATRIX/sub x/: control design and model building CAE capability for utility systems

    International Nuclear Information System (INIS)

    Automatic control of powerplants, transmission systems, and electric networks has been used as long as such systems have existed. In general terms, the problem of plant control is one of manipulating a set of inputs such that sufficient power will be generated and transmitted to meet demand, while many plant parameters remain within specified limits. Earlier, the emphasis of automatic control had been safe operation of power plants and good regulation of desired parameters. More emphasis is now being placed on economic operation, robustness and an extremely high fault tolerance. A good example is the operation of a Boiling Water Reactor (BWR). ISI has developed a computer-aided-engineering (CAE) system MATRIX/sub x/ for the design, analysis and verification of multivariable as well as nonlinear control systems. MATRIX/sub x/ and an associated capability System Build are unique in that they provide modeling, simulation, optimization and control design facilities in an integrated environment with a common data base. MATRIX/sub x/ is the leading CAE control system design package. The capabilities of Version 4.0 of MATRIX/sub x/ and SYSTEM BUILD are discussed and an approach to integrate Modular Modeling System (MMS) features into MATRIX/sub x/ is proposed

  14. The Effects of Omega-3 Fatty Acids on Matrix Metalloproteinase-9 Production and Cell Migration in Human Immune Cells: Implications for Multiple Sclerosis

    Directory of Open Access Journals (Sweden)

    Lynne Shinto

    2011-01-01

    Full Text Available In multiple sclerosis (MS, compromised blood-brain barrier (BBB integrity contributes to inflammatory T cell migration into the central nervous system. Matrix metalloproteinase-9 (MMP-9 is associated with BBB disruption and subsequent T cell migration into the CNS. The aim of this paper was to evaluate the effects of omega-3 fatty acids on MMP-9 levels and T cell migration. Peripheral blood mononuclear cells (PBMC from healthy controls were pretreated with two types of omega-3 fatty acids, eicosapentaenoic acid (EPA, and docosahexaenoic acid (DHA. Cell supernatants were used to determine MMP-9 protein and activity levels. Jurkat cells were pretreated with EPA and DHA and were added to fibronectin-coated transwells to measure T cell migration. EPA and DHA significantly decreased MMP-9 protein levels, MMP-9 activity, and significantly inhibited human T cell migration. The data suggest that omega-3 fatty acids may benefit patients with multiple sclerosis by modulating immune cell production of MMP-9.

  15. Lyapunov Functions and Solutions of the Lyapunov Matrix Equation for Marginally Stable Systems

    DEFF Research Database (Denmark)

    Kliem, Wolfhard; Pommer, Christian

    2000-01-01

    of the Lyapunov matrix equation and characterize the set of matrices $(B, C)$ which guarantees marginal stability. The theory is applied to gyroscopic systems, to indefinite damped systems, and to circulatory systems, showing how to choose certain parameter matrices to get sufficient conditions for marginal...

  16. Pore formation mechanism of porous poly(DL-lactic acid) matrix membrane.

    Science.gov (United States)

    Phaechamud, Thawatchai; Chitrattha, Sasiprapa

    2016-04-01

    Porous PLA structure has been widely used in cell transplantation, drug carrier and wound dressing. The porous structure can be controlled depending on the choice of the polymer, solvent, nonsolvent and preparation parameters. In this study, the porous PLA matrix membranes were prepared by adding PEG 400 in PLA solution using dichloromethane (DCM) as solvent prior to casting. The influence of other liquids as co-solvent on pore formation and the structural change during membrane formation were evaluated. The co-solvents affected both porous topography and mechanical properties of PLA membrane. The porous matrix were produced when the non-solvent of PLA was used as co-solvent. Cryo-SEM micrographs revealed that PEG 400 still remained in the PLA porous matrix membrane. From the tracking of the structural change during film formation, the PLA-PEG solution changed into porous structure by liquid liquid phase separation and solidification processes, respectively. Thermogravimetric analysis revealed that PLA-PEG in DCM solution exhibited the two-step of weight loss, the first step occurred from DCM evaporation and the second step occurred from the degradation of PLA-PEG matrix. The liquid-liquid phase separation and solidification started when the amount of DCM was higher than PEG 400 for 2.67 folds and DCM amount was equal to that of PEG 400, respectively. These results could clarify the pore formation mechanism of porous PLA membrane and will be useful for the further investigation and application. PMID:26838905

  17. A Unisonant r-Matrix Structure of Integrable Systems and Its Reductions

    Institute of Scientific and Technical Information of China (English)

    QIAO Zhi-Jun; Walter STRAMPP

    2000-01-01

    A new method is presented to generate finite dimensional integrable systems. Our starting point is a generalized Lax matrix instead of usual Lax pair. Then a unisonant r-matrix structure and a set of generalized Hamiltonian functions are constructed. It can be clearly seen that various constrained integrable flows by nonlinearization method, such as the c-AKNS, c-MKdV, c-Toda, etc., are derived from the reduction of this structure. Furthermore, some new integrable flows are produced

  18. Upper Triangular Matrix of Lie Algebra and a New Discrete Integrable Coupling System

    Institute of Scientific and Technical Information of China (English)

    YU Fa-Jun; ZHANG Hong-Qing

    2007-01-01

    The upper triangular matrix of Lie algebra is used to construct integrable couplings of discrete solition equations.Correspondingly,a feasible way to construct integrable couplings is presented.A nonlinear lattice soliton equation spectral problem is obtained and leads to a novel hierarchy of the nonlinear lattice equation hierarchy.It indicates that the study of integrable couplings using upper triangular matrix of Lie algebra is an important step towards constructing integrable systems.

  19. Density-matrix approach for an interacting polariton system

    OpenAIRE

    Savenko, I.G.; Magnusson, E. B.; Shelykh, I.A.

    2011-01-01

    Using the Lindblad approach we develop a general formalism for theoretical description of a spatially inhomogeneous bosonic system with dissipation provided by the interaction of bosons with a phonon bath. We apply our results to model the dynamics of an interacting one-dimensional polariton system in real space and time, analyzing in detail the role of polariton-polariton and polariton-phonon interactions.

  20. The effect of an autologous cellular gel-matrix integrated implant system on wound healing

    Directory of Open Access Journals (Sweden)

    Morales Patricio

    2010-06-01

    Full Text Available Abstract Background This manuscript reports the production and preclinical studies to examine the tolerance and efficacy of an autologous cellular gel-matrix integrated implant system (IIS aimed to treat full-thickness skin lesions. Methods The best concentration of fibrinogen and thrombin was experimentally determined by employing 28 formula ratios of thrombin and fibrinogen and checking clot formation and apparent stability. IIS was formed by integrating skin cells by means of the in situ gelification of fibrin into a porous crosslinked scaffold composed of chitosan, gelatin and hyaluronic acid. The in vitro cell proliferation within the IIS was examined by the MTT assay and PCNA expression. An experimental rabbit model consisting of six circular lesions was utilized to test each of the components of the IIS. Then, the IIS was utilized in an animal model to cover a 35% body surface full thickness lesion. Results The preclinical assays in rabbits demonstrated that the IIS was well tolerated and also that IIS-treated rabbit with lesions of 35% of their body surface, exhibited a better survival rate (p = 0,06. Conclusion IIS should be further studied as a new wound dressing which shows promising properties, being the most remarkable its good biological tolerance and cell growth promotion properties.

  1. Diglycolamic acid anchored on polyamine matrix for the mutual separation of Eu(III) and Am(III)

    Energy Technology Data Exchange (ETDEWEB)

    Suneesh, A.S.; Syamala, K.V.; Venkatesan, K.A.; Antony, M.P.; Vasudeva Rao, P.R. [Indira Gandhi Centre for Atomic Research, Kalpakkam (India). Fuel Chemistry Div.

    2016-04-01

    Diglycolamic acid was anchored on a polyamine matrix and the product (PA-DGAH) was characterized by ion-exchange capacity measurement, TG-DTA and FT-IR spectroscopy. The extraction behavior of Am(III) and Eu(III) in PA-DGAH was studied from dilute nitric acid medium to examine the feasibility using the anchored adsorbent for their mutual separation. The effect of various parameters such as the duration of equilibration, concentration of europium, nitric acid and diethylenetriaminepentaacetic acid (DTPA) in aqueous phase on the distribution coefficient (K{sub d}) of Am(III) and Eu(III) was studied. The distribution coefficient decreased with increase in the concentration of nitric acid. Rapid extraction of metal ions in the initial stages of equilibration followed by the establishment of equilibrium occurred within 4 h. The data on the rate of uptake of Am(III) and Eu(III) were fitted into pseudo-first order and pseudo-second order rate equation. The extraction isotherm was fitted to Langmuir and Freundlich adsorption models and the apparent europium extraction capacity was determined. The mechanism of extraction was elucidated and the conditions needed for efficient separation of Am(III) from Eu(III) was optimized using DTPA. The study indicated the possibility of using PA-DGAH for the separation of Eu(III) from Am(III) with high separation factors.

  2. Skew-orthogonal polynomials, differential systems and random matrix theory

    International Nuclear Information System (INIS)

    We study skew-orthogonal polynomials with respect to the weight function exp[-2V (x)], with V (x) = ΣK=12d (uK/K)xK, u2d > 0, d > 0. A finite subsequence of such skew-orthogonal polynomials arising in the study of Orthogonal and Symplectic ensembles of random matrices, satisfy a system of differential-difference-deformation equation. The vectors formed by such subsequence has the rank equal to the degree of the potential in the quaternion sense. These solutions satisfy certain compatibility condition and hence admit a simultaneous fundamental system of solutions. (author)

  3. On stabilization for a class of nonlinear stochastic time-delay systems: a matrix inequality approach

    Institute of Scientific and Technical Information of China (English)

    Weihai ZHANG; Xuezhen LIU; Shulan KONG; Qinghua LI

    2006-01-01

    This paper treats the feedback stabilization of nonlinear stochastic time-delay systems with state and control-dependent noise. Some locally (globally) robustly stabilizable conditions are given in terms of matrix inequalities that are independent of the delay size. When it is applied to linear stochastic time-delay systems, sufficient conditions for the state-feedback stabilization are presented via linear matrix inequalities. Several previous results are extended to more general systems with both state and control-dependent noise, and easy computation algorithms are also given.

  4. The decoupling of second-order linear systems with a singular mass matrix

    Science.gov (United States)

    Kawano, Daniel T.; Morzfeld, Matthias; Ma, Fai

    2013-12-01

    It was demonstrated in earlier work that a nondefective, linear dynamical system with an invertible mass matrix in free or forced motion may be decoupled in the configuration space by a real and isospectral transformation. We extend this work by developing a procedure for decoupling a linear dynamical system with a singular mass matrix in the configuration space, transforming the original differential-algebraic system into decoupled sets of real, independent, first- and second-order differential equations. Numerical examples are provided to illustrate the application of the decoupling procedure.

  5. Evaluation of microwave digestion systems for mercury recovery in an oil matrix

    Energy Technology Data Exchange (ETDEWEB)

    Whitaker, M.J.; Clymire, J.W.

    1997-09-01

    The scope of this document is to characterize three microwave systems developed by CEM Corporation. The purpose of this investigative work was to evaluate the performance of each system for dissolution qualities and the recovery of mercury in an oil based matrix. The microwave systems evaluated were the heavy duty vessel system (HDV), the advanced composite system (ACV), and the open vessel system (OVS). All three systems have automated features, but all systems are limited by one factor or another. EPA method 3051 was the procedure used for sample preparation for this project. This particular microwave digestion method can also be used for other metal analytes of interest. Of the three different systems, only the HDV (now UDV) demonstrated complete digestion of the oil based matrix in a one step process and acceptable mercury recoveries.

  6. High Performance Control of Matrix Converter Fed Induction Motor Drive System

    Institute of Scientific and Technical Information of China (English)

    孙凯; 黄立培; MATSUSE Kouki

    2007-01-01

    Matrix converter fed motor drive is superior to pulse width modulation inverter drives since it not only provides bi-directional power flow, sinusoidal input/output currents, unity input power factor, but also allows a compact design due to the lack of DC-link capacitors for energy storage. In this paper, model and control of matrix converter fed induction motor drive system are analyzed. A combined control strategy is simplified and improved, which realizes space vector pulse width modulation of matrix converter and rotor flux oriented vector control technique for induction motor drive simultaneously. This control strategy combines the advantages of matrix converter with the good drive performance of vector control technique. Experimental results demonstrate the feasibility and effectiveness of the proposed control strategy.

  7. Negative Ion In-Source Decay Matrix-Assisted Laser Desorption/Ionization Mass Spectrometry for Sequencing Acidic Peptides

    Science.gov (United States)

    McMillen, Chelsea L.; Wright, Patience M.; Cassady, Carolyn J.

    2016-05-01

    Matrix-assisted laser desorption/ionization (MALDI) in-source decay was studied in the negative ion mode on deprotonated peptides to determine its usefulness for obtaining extensive sequence information for acidic peptides. Eight biological acidic peptides, ranging in size from 11 to 33 residues, were studied by negative ion mode ISD (nISD). The matrices 2,5-dihydroxybenzoic acid, 2-aminobenzoic acid, 2-aminobenzamide, 1,5-diaminonaphthalene, 5-amino-1-naphthol, 3-aminoquinoline, and 9-aminoacridine were used with each peptide. Optimal fragmentation was produced with 1,5-diaminonphthalene (DAN), and extensive sequence informative fragmentation was observed for every peptide except hirudin(54-65). Cleavage at the N-Cα bond of the peptide backbone, producing c' and z' ions, was dominant for all peptides. Cleavage of the N-Cα bond N-terminal to proline residues was not observed. The formation of c and z ions is also found in electron transfer dissociation (ETD), electron capture dissociation (ECD), and positive ion mode ISD, which are considered to be radical-driven techniques. Oxidized insulin chain A, which has four highly acidic oxidized cysteine residues, had less extensive fragmentation. This peptide also exhibited the only charged localized fragmentation, with more pronounced product ion formation adjacent to the highly acidic residues. In addition, spectra were obtained by positive ion mode ISD for each protonated peptide; more sequence informative fragmentation was observed via nISD for all peptides. Three of the peptides studied had no product ion formation in ISD, but extensive sequence informative fragmentation was found in their nISD spectra. The results of this study indicate that nISD can be used to readily obtain sequence information for acidic peptides.

  8. Computing the Moore-Penrose Inverse of a Matrix with a Computer Algebra System

    Science.gov (United States)

    Schmidt, Karsten

    2008-01-01

    In this paper "Derive" functions are provided for the computation of the Moore-Penrose inverse of a matrix, as well as for solving systems of linear equations by means of the Moore-Penrose inverse. Making it possible to compute the Moore-Penrose inverse easily with one of the most commonly used Computer Algebra Systems--and to have the blueprint…

  9. Acid mine water aeration and treatment system

    Science.gov (United States)

    Ackman, Terry E.; Place, John M.

    1987-01-01

    An in-line system is provided for treating acid mine drainage which basically comprises the combination of a jet pump (or pumps) and a static mixer. The jet pump entrains air into the acid waste water using a Venturi effect so as to provide aeration of the waste water while further aeration is provided by the helical vanes of the static mixer. A neutralizing agent is injected into the suction chamber of the jet pump and the static mixer is formed by plural sections offset by 90 degrees.

  10. PET image reconstruction with rotationally symmetric polygonal pixel grid based highly compressible system matrix

    International Nuclear Information System (INIS)

    To achieve a maximum compression of system matrix in positron emission tomography (PET) image reconstruction, we proposed a polygonal image pixel division strategy in accordance with rotationally symmetric PET geometry. Geometrical definition and indexing rule for polygonal pixels were established. Image conversion from polygonal pixel structure to conventional rectangular pixel structure was implemented using a conversion matrix. A set of test images were analytically defined in polygonal pixel structure, converted to conventional rectangular pixel based images, and correctly displayed which verified the correctness of the image definition, conversion description and conversion of polygonal pixel structure. A compressed system matrix for PET image recon was generated by tap model and tested by forward-projecting three different distributions of radioactive sources to the sinogram domain and comparing them with theoretical predictions. On a practical small animal PET scanner, a compress ratio of 12.6:1 of the system matrix size was achieved with the polygonal pixel structure, comparing with the conventional rectangular pixel based tap-mode one. OS-EM iterative image reconstruction algorithms with the polygonal and conventional Cartesian pixel grid were developed. A hot rod phantom was detected and reconstructed based on these two grids with reasonable time cost. Image resolution of reconstructed images was both 1.35 mm. We conclude that it is feasible to reconstruct and display images in a polygonal image pixel structure based on a compressed system matrix in PET image reconstruction. (authors)

  11. Investigating the use of coupling agents to improve the interfacial properties between a resorbable phosphate glass and polylactic acid matrix.

    Science.gov (United States)

    Hasan, Muhammad Sami; Ahmed, Ifty; Parsons, Andrew J; Rudd, Chris D; Walker, Gavin S; Scotchford, Colin A

    2013-09-01

    Eight different chemicals were investigated as potential candidate coupling agents for phosphate glass fibre reinforced polylactic acid composites. Evidence of reaction of the coupling agents with phosphate glass and their effect on surface wettability and glass degradation were studied along with their principle role of improving the interface between glass reinforcement and polymer matrix. It was found that, with an optimal amount of coupling agent on the surface of the glass/polymer, interfacial shear strength improved by a factor of 5. Evidence of covalent bonding between agent and glass was found for three of the coupling agents investigated, namely: 3-aminopropyltriethoxysilane; etidronic acid and hexamethylene diisocyanate. These three coupling agents also improved the interfacial shear strength and increased the hydrophobicity of the glass surface. It is expected that this would provide an improvement in the macroscopic properties of full-scale composites fabricated from the same materials which may also help to retain these properties for the desired length of time by retarding the breakdown of the fibre/matrix interface within these composites.

  12. Adaptive Backstepping controller design and implementation for a matrix-converter-based IM drive system

    OpenAIRE

    R.R. Joshi; R.A. Gupta; A.K. Wadhwani

    2007-01-01

    A systematic controller design and implementation for a matrix-converter-based induction motor drive system is proposed. A nonlinear adaptive backstepping controller is proposed to improve the speed and position responses of the induction motor system. By using the proposed adaptive backstepping controller, the system can track a time-varying speed command and a time-varying position command well. Moreover, the system has a good load disturbance rejection capability. The realization of the co...

  13. Biological studies of matrix metalloproteinase sensitive drug delivery systems

    DEFF Research Database (Denmark)

    Johansen, Pia Thermann

    of a negatively charged lipopeptide-PEG conjugates containing a MMP-2 cleavable peptide, which leads to cationic liposomes with enhanced ability to interact with negatively charged cell membranes. Activation of the liposomal formulation developed here resulted in enhanced association of liposomes with cancer......Cancer, which is a group of diseases characterized by cells with elevated replication rate and compromised DNA damage response, is often treated with cytotoxic drugs, chemotherapeutics, inducing DNA damage that results in cell death. The use of chemotherapeutics in the clinic, however, is limited...... investigated the interaction between liposomes and cell populations in the blood, resulting in a novel liposomal system for specific targeting to CD14+ monocytes. Monocytes play an important role in in ammatory diseases, which are commonly treated with steroids, through their secretion of proin ammatory...

  14. TWO ITERATION METHODS FOR SOLVING LINEAR ALGEBRAIC SYSTEMS WITH LOW ORDER MATRIX A AND HIGH ORDER MATRIX B: Y = (A B)Y + Ф

    Institute of Scientific and Technical Information of China (English)

    Shuang-suo Zhao; Zhang-hua Luo; Guo-feng Zhang

    2000-01-01

    This paper presents optimum an one-parameter iteration (OOPI) method and a multi-parameter iteration direct (MPID) method for efficiently solving linear algebraic systems with low order matrix A and high order matrix B: Y = (A B)Y +Ф. On parallel computers (also on serial computer) the former will be efficient, even very efficient under certain conditions, the latter will be universally very efficient.

  15. Adaptive control of linear multivariable systems with high frequency gain matrix hurwitz

    Institute of Scientific and Technical Information of China (English)

    Ying ZHOU; Yuqiang WU; Shumin FEI

    2005-01-01

    A new adaptive control scheme is proposed for multivariable model reference adaptive control(MRAC) systems based on the nonlinear backstepping approach with vector form.The assumption on a priori knowledge of the high frequency gain matrix in existing results is relaxed and the new required condition for the high frequency gain matrix can be easily checked for certain plants so that the proposed method is widely applicable.This control scheme guarantees the global stability of the closed-loop systems and the tracking error can be arbitrary small.The simulation result for an application example shows the validity of the proposed nonlinear adaptive scheme.

  16. Adaptive Neuro Fuzzy Inference System Based DTC Control for Matrix Converter

    Directory of Open Access Journals (Sweden)

    Venugopal Chitra

    2012-04-01

    Full Text Available In this study an Adaptive Neuro Fuzzy Inference System is introduced to select the switching states of Matrix Converters. Matrix converters have received more attention in research and industrial application due its advantages like four quadrant operation, sinusoidal input and output waveforms, controllable displacement factor, less number of switches etc., Matrix Converters are efficient in speed control of Induction motors than the conventional converters. There are two different control techniques namely field oriented control and Direct Torque Control systems available for closed loop operation of induction motors. The Direct Torque Control technique provides control of torque and flux directly. The major drawback of Direct Torque Control technique is the presence of ripples in torque and flux curves. This due to the presence of two level and three level hysteresis controllers in torque and flux control stages respectively. Also the conventional space vector and look up table method of switching state selection reduces the accuracy of switch state selection in the appropriate time width. This reduces the speed control performance of the motor. Also in this paper the hysteresis controllers are replaced by fuzzy controllers. the complete ANFIS based DTC for Matrix Converter is simulated in MATLAB/SIMULINK and the results shows that the use of Adaptive neuro fuzzy inference in Matrix Converter system increases the speed control performance of Induction Motor.

  17. Numerical modelling of transdermal delivery from matrix systems: parametric study and experimental validation with silicone matrices.

    Science.gov (United States)

    Snorradóttir, Bergthóra S; Jónsdóttir, Fjóla; Sigurdsson, Sven Th; Másson, Már

    2014-08-01

    A model is presented for transdermal drug delivery from single-layered silicone matrix systems. The work is based on our previous results that, in particular, extend the well-known Higuchi model. Recently, we have introduced a numerical transient model describing matrix systems where the drug dissolution can be non-instantaneous. Furthermore, our model can describe complex interactions within a multi-layered matrix and the matrix to skin boundary. The power of the modelling approach presented here is further illustrated by allowing the possibility of a donor solution. The model is validated by a comparison with experimental data, as well as validating the parameter values against each other, using various configurations with donor solution, silicone matrix and skin. Our results show that the model is a good approximation to real multi-layered delivery systems. The model offers the ability of comparing drug release for ibuprofen and diclofenac, which cannot be analysed by the Higuchi model because the dissolution in the latter case turns out to be limited. The experiments and numerical model outlined in this study could also be adjusted to more general formulations, which enhances the utility of the numerical model as a design tool for the development of drug-loaded matrices for trans-membrane and transdermal delivery.

  18. Matrix Domain Modulates HIV-1 Gag's Nucleic Acid Chaperone Activity via Inositol Phosphate Binding ▿

    OpenAIRE

    Jones, Christopher P.; Datta, Siddhartha A.K.; Rein, Alan; Rouzina, Ioulia; Musier-Forsyth, Karin

    2010-01-01

    Retroviruses replicate by reverse transcribing their single-stranded RNA genomes into double-stranded DNA using specific cellular tRNAs to prime cDNA synthesis. In HIV-1, human tRNA3Lys serves as the primer and is packaged into virions during assembly. The viral Gag protein is believed to chaperone tRNA3Lys placement onto the genomic RNA primer binding site; however, the timing and possible regulation of this event are currently unknown. Composed of the matrix (MA), capsid (CA), nucleocapsid ...

  19. A System of Four Matrix Equations over von Neumann Regular Rings and Its Applications

    Institute of Scientific and Technical Information of China (English)

    Qing Wen WANG

    2005-01-01

    We consider the system of four linear matrix equations A1X = C1, XB2 = C2, A3XB3 = C3 and A4XB4 = C4 over(R) , an arbitrary yon Neumann regular ring with identity. A necessary and sufficient condition for the existence and the expression of the general solution to the system are derived. As applications, necessary and sufficient conditions are given for the system of matrix equations A1X = C1 and A3X = C3 to have a bisymmetric solution, the system of matrix equations A1X = C1and A3XB3 = C3 to have a perselfconjugate solution over(R) with an involution and char ≠(R)2,respectively. The representations of such solutions are also presented. Moreover, some auxiliary results on other systems over(R)are obtained. The previous known results on some systems of matrix equations are special cases of the new results.

  20. Polarography of uranium(VI)-salicylic acid system

    International Nuclear Information System (INIS)

    Uranium(VI)-salicylic acid system has been studied polarographically in perchloric acid medium. Varying concentrations of HClO4 and salicylic acid have been used. The nature of the polarographic waves is irreversible. (author)

  1. Spectrophotometric method for fast quantification of ascorbic acid and dehydroascorbic acid in simple matrix for kinetics measurements.

    Science.gov (United States)

    Gómez Ruiz, Braulio; Roux, Stéphanie; Courtois, Francis; Bonazzi, Catherine

    2016-11-15

    A simple, rapid and reliable method was developed for quantifying ascorbic (AA) and dehydroascorbic (DHAA) acids and validated in 20mM malate buffer (pH 3.8). It consists in a spectrophotometric measurement of AA, either directly on the solution added with metaphosphoric acid or after reduction of DHAA into AA by dithiothreitol. This method was developed with real time measurement of reactions kinetics in bulk reactors in mind, and was checked in terms of linearity, limits of detection and quantification, fidelity and accuracy. The linearity was found satisfactory on the range of 0-6.95mM with limits of detection and quantification of 0.236mM and 0.467mM, respectively. The method was found acceptable in terms of fidelity and accuracy with a coefficient of variation for repeatability and reproducibility below 6% for AA and below 15% for DHAA, and with a recovery range of 97-102% for AA and 88-112% for DHAA. PMID:27283671

  2. Stearic acid and high molecular weight PEO as matrix for the highly water soluble metoprolol tartrate in continuous twin-screw melt granulation.

    Science.gov (United States)

    Monteyne, Tinne; Adriaensens, Peter; Brouckaert, Davinia; Remon, Jean-Paul; Vervaet, Chris; De Beer, Thomas

    2016-10-15

    Granules with release-sustaining properties were developed by twin screw hot melt granulation (HMG) using a combination of stearic acid (SA) and high molecular weight polyethylene oxide (PEO) as matrix for a highly water soluble model drug, metoprolol tartrate (MPT). Earlier studies demonstrated that mixing molten SA and PEO resulted in hydrogen bond formation between hydroxyl groups of fatty acid molecules and ether groups in PEO chains. These molecular interactions might be beneficial in order to elevate the sustained release effect of drugs from a SA/PEO matrix. This study aims to investigate the continuous twin screw melt granulation technique to study the impact of a SA/PEO matrix on the dissolution rate of a highly water soluble drug (MPT). Decreasing the SA/PEO ratio improved the release-sustaining properties of the matrix. The solid state of the granules was characterized using differential scanning calorimetry (DSC), nuclear magnetic resonance (NMR), X-ray diffraction (XRD), Raman spectroscopy, Fourier transform infrared (FTIR) and near infrared chemical imaging (NIR-CI) in order to understand the dissolution behavior. The results revealed a preferential interaction of the MPT molecules with stearic acid impeding the PEO to form hydrogen bonds with the stearic acid chains. However, this allowed the PEO chains to recrystallize inside the stearic acid matrix after granulation, hence, elevating the release-sustaining characteristics of the formulation. PMID:27452420

  3. Identification of Protein-Protein Interactions via a Novel Matrix-Based Sequence Representation Model with Amino Acid Contact Information.

    Science.gov (United States)

    Ding, Yijie; Tang, Jijun; Guo, Fei

    2016-01-01

    Identification of protein-protein interactions (PPIs) is a difficult and important problem in biology. Since experimental methods for predicting PPIs are both expensive and time-consuming, many computational methods have been developed to predict PPIs and interaction networks, which can be used to complement experimental approaches. However, these methods have limitations to overcome. They need a large number of homology proteins or literature to be applied in their method. In this paper, we propose a novel matrix-based protein sequence representation approach to predict PPIs, using an ensemble learning method for classification. We construct the matrix of Amino Acid Contact (AAC), based on the statistical analysis of residue-pairing frequencies in a database of 6323 protein-protein complexes. We first represent the protein sequence as a Substitution Matrix Representation (SMR) matrix. Then, the feature vector is extracted by applying algorithms of Histogram of Oriented Gradient (HOG) and Singular Value Decomposition (SVD) on the SMR matrix. Finally, we feed the feature vector into a Random Forest (RF) for judging interaction pairs and non-interaction pairs. Our method is applied to several PPI datasets to evaluate its performance. On the S . c e r e v i s i a e dataset, our method achieves 94 . 83 % accuracy and 92 . 40 % sensitivity. Compared with existing methods, and the accuracy of our method is increased by 0 . 11 percentage points. On the H . p y l o r i dataset, our method achieves 89 . 06 % accuracy and 88 . 15 % sensitivity, the accuracy of our method is increased by 0 . 76 % . On the H u m a n PPI dataset, our method achieves 97 . 60 % accuracy and 96 . 37 % sensitivity, and the accuracy of our method is increased by 1 . 30 % . In addition, we test our method on a very important PPI network, and it achieves 92 . 71 % accuracy. In the Wnt-related network, the accuracy of our method is increased by 16 . 67 % . The source code and all datasets are available

  4. Chitosan-polycarbophil interpolyelectrolyte complex as an excipient for bioadhesive matrix systems to control macromolecular drug delivery.

    Science.gov (United States)

    Lu, Zhilei; Chen, Weiyang; Hamman, Josias H; Ni, Jian; Zhai, Xiaoling

    2008-01-01

    The in vitro performance of monolithic matrix systems containing the interpolyelectrolyte complex between chitosan and polycarbophil as excipient was evaluated in terms of their swelling, bioadhesive, and drug release properties. The different matrix systems showed excellent swelling properties without erosion, except for the formulation containing the highest quantity chitosan-polycarbophil complex that exhibited surface erosion in addition to swelling. All the different matrix systems exhibited significantly higher bioadhesive properties than the control group. Furthermore, they showed controlled insulin release without an initial burst release effect. However, only the matrix system that exhibited surface erosion in combination with swelling approached zero-order release.

  5. Linear Matrix Inequalities for Analysis and Control of Linear Vector Second-Order Systems

    DEFF Research Database (Denmark)

    Adegas, Fabiano Daher; Stoustrup, Jakob

    2015-01-01

    SUMMARY Many dynamical systems are modeled as vector second-order differential equations. This paper presents analysis and synthesis conditions in terms of LMI with explicit dependence in the coefficient matrices of vector second-order systems. These conditions benefit from the separation between...... the Lyapunov matrix and the system matrices by introducing matrix multipliers, which potentially reduce conservativeness in hard control problems. Multipliers facilitate the usage of parameter-dependent Lyapunov functions as certificates of stability of uncertain and time-varying vector second-order systems....... The conditions introduced in this work have the potential to increase the practice of analyzing and controlling systems directly in vector second-order form. Copyright © 2014 John Wiley & Sons, Ltd....

  6. Rotor Bearing System Analysis Using the Transfer Matrix Method with Thickness Assumption of Disk and Bearing

    CERN Document Server

    Ghasemalizadeh, Omid; Sadeghi, Hossein; Ahmadian, Mohammad Taghi

    2013-01-01

    One of the methods to find the natural frequencies of rotating systems is the application of the transfer matrix method. In this method the rotor is modeled as several elements along the shaft which have their own mass and moment of inertia. Using these elements, the entire continuous system is discretized and the corresponding differential equation can be stated in matrix form. The bearings at the end of the shaft are modeled as equivalent spring and dampers which are applied as boundary conditions to the discretized system. In this paper the dynamics of a rotor-bearing system is analyzed, considering the gyroscopic effect. The thickness of the disk and bearings is also taken into account. Continuous model is used for shaft. Results Show that, the stiffness of the shaft and the natural frequencies of the system increase, while the amplitude of vibration decreases as a consequence of increasing the thickness of the bearing.

  7. Linear System of Equations, Matrix Inversion, and Linear Programming Using MS Excel

    Science.gov (United States)

    El-Gebeily, M.; Yushau, B.

    2008-01-01

    In this note, we demonstrate with illustrations two different ways that MS Excel can be used to solve Linear Systems of Equation, Linear Programming Problems, and Matrix Inversion Problems. The advantage of using MS Excel is its availability and transparency (the user is responsible for most of the details of how a problem is solved). Further, we…

  8. Global stabilization of linear periodically time-varying switched systems via matrix inequalities

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    In this paper, we address the stabilization problem for linear periodically time-varying switched systems.Using discretization technique, we derive new conditions for the global stabilizability in terms of the solution of matrix inequalities. An algorithm for finding stabilizing controller and switching strategy is presented.

  9. Chitosan-polycarbophil complexes in swellable matrix systems for controlled drug release.

    Science.gov (United States)

    Lu, Z; Chen, W; Hamman, J H

    2007-10-01

    A prerequisite for progress in the design of novel drug delivery systems is the development of excipients that are capable of fulfilling multifunctional roles such as controlling the release of the drug according to the therapeutic needs. Although several polymers have been utilised in the development of specialised drug delivery systems, their scope in dosage form design can be enlarged through combining different polymers. When a polymer is cross-linked or complexed with an oppositely charged polyelectrolyte, a three-dimensional network is formed in which the drug can be incorporated to control its release. The swelling properties and release kinetics of two model drugs with different water solubilities (i.e. diltiazem and ibuprofen) from monolithic matrix tablets consisting of an interpolyelectrolyte complex between chitosan and polycarbophil are reported. Matrix tablets consisting of this polymeric complex without drug or excipients exhibited extremely high swelling properties that are completely reversible upon drying. The drug release from matrix systems with different formulations depended on the concentration of the chitosan-polycarbophil interpolyelectrolyte complex and approached zero order release kinetics for both model drugs. The chitosan-polycarbophil interpolyelectrolyte complex has demonstrated a high potential as an excipient for the production of swellable matrix systems with controlled drug release properties.

  10. Development of an extracellular matrix delivery system for effective intramyocardial injection in ischemic tissue.

    Science.gov (United States)

    Slaughter, Mark S; Soucy, Kevin G; Matheny, Robert G; Lewis, Beecher C; Hennick, Michael F; Choi, Young; Monreal, Gretel; Sobieski, Michael A; Giridharan, Guruprasad A; Koenig, Steven C

    2014-01-01

    Biomaterials with direct intramyocardial injection devices have been developed and are being investigated as a potential cardiac regenerative therapy for end-stage ischemic heart failure. Decellularized extracellular matrix (ECM) has been shown to improve cardiac function and attenuate or reverse pathologic remodeling cascades. CorMatrix Cardiovascular, Inc. has developed a porcine small intestinal submucosa-derived particulate extracellular matrix (P-ECM) and ECM Delivery System to provide uniform and controlled intramyocardial delivery of the injectable P-ECM material into infarcted regions. The CorMatrix ECM Delivery System is composed of a Multi-Needle P-ECM Syringe Assembly, Automated Injection Controller, and Tissue Depth Measurement System (portable ultrasound). Feasibility of the P-ECM delivery system was tested intraoperatively in a chronic ischemic heart failure bovine model (n = 11), and demonstrated the ability to control injection volume (0.1-1.0 ml) and depth of penetration (3-5 mm) under regulated injection pressure (150 psi CO2) into the ischemic region. Targeted intramyocardial delivery of P-ECM may improve efficacy and enable development of novel patient-specific therapy. PMID:25232775

  11. Algebraic method for analysis of nonlinear systems with a normal matrix

    International Nuclear Information System (INIS)

    A promising method has been proposed for analyzing a class of quasilinear nonautonomous systems of differential equations whose matrix can be represented as a sum of nonlinear normal matrices, which makes it possible to analyze stability without using the Lyapunov functions

  12. Acceleration of criticality analysis solution convergence by matrix eigenvector for a system with weak neutron interaction

    Energy Technology Data Exchange (ETDEWEB)

    Nomura, Yasushi; Takada, Tomoyuki; Kuroishi, Takeshi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Kadotani, Hiroyuki [Shizuoka Sangyo Univ., Iwata, Shizuoka (Japan)

    2003-03-01

    In the case of Monte Carlo calculation to obtain a neutron multiplication factor for a system of weak neutron interaction, there might be some problems concerning convergence of the solution. Concerning this difficulty in the computer code calculations, theoretical derivation was made from the general neutron transport equation and consideration was given for acceleration of solution convergence by using the matrix eigenvector in this report. Accordingly, matrix eigenvector calculation scheme was incorporated together with procedure to make acceleration of convergence into the continuous energy Monte Carlo code MCNP. Furthermore, effectiveness of acceleration of solution convergence by matrix eigenvector was ascertained with the results obtained by applying to the two OECD/NEA criticality analysis benchmark problems. (author)

  13. Investigation of fracture-matrix interaction: Preliminary experiments in a simple system

    Energy Technology Data Exchange (ETDEWEB)

    Foltz, S.D. [New Mexico Univ., Albuquerque, NM (United States). Dept. of Physics and Astronomy; Tidwell, V.C.; Glass, R.J.; Sobolik, S.R. [Sandia National Labs., Albuquerque, NM (United States)

    1992-12-31

    Paramount to the modeling of unsaturated flow and transport through fractured porous media is a clear understanding of the processes controlling fracture-matrix interaction. As a first step toward such an understanding, two preliminary experiments have been performed to investigate the influence of matrix imbibition on water percolation through unsaturated fractures in the plane normal to the fracture. Test systems consisted of thin slabs of either tuff or an analog material cut by a single vertical fracture into which a constant fluid flux was introduced. Transient moisture content and solute concentration fields were imaged by means of x-ray absorption. Flow fields associated with the two different media were significantly different owing to differences in material properties relative to the imposed flux. Richards` equation was found to be a valid means of modeling the imbibition of water into the tuff matrix from a saturated fracture for the current experiment.

  14. Toric Calabi-Yau threefolds as quantum integrable systems. R-matrix and RTT relations

    CERN Document Server

    Awata, Hidetoshi; Mironov, Andrei; Morozov, Alexei; Morozov, Andrey; Ohkubo, Yusuke; Zenkevich, Yegor

    2016-01-01

    R-matrix is explicitly constructed for simplest representations of the Ding-Iohara-Miki algebra. The calculation is straightforward and significantly simpler than the one through the universal R-matrix used for a similar calculation in the Yangian case by A.~Smirnov but less general. We investigate the interplay between the R-matrix structure and the structure of DIM algebra intertwiners, i.e.\\ of refined topological vertices and show that the R-matrix is diagonalized by the action of the spectral duality belonging to the SL(2,Z) group of DIM algebra automorphisms. We also construct the T-operators satisfying the RTT relations with the R-matrix from refined amplitudes on resolved conifold. We thus show that topological string theories on the toric Calabi-Yau threefolds can be naturally interpreted as lattice integrable models. Integrals of motion for these systems are related to q-deformation of the reflection matrices of the Liouville/Toda theories.

  15. Transfer matrix analysis of backscattering and reflection effects on WDM-PON systems.

    Science.gov (United States)

    Simatupang, Joni Welman; Lee, San-Liang

    2013-11-18

    This paper proposes using power transfer matrix analysis to characterize the effects of Rayleigh backscattering and Fresnel reflection on WDM-PON systems. The modeling of a WDM-PON system can be carried out simply by matrix multiplication of the corresponding matrices for all the building blocks, where all possible guided backward lights and resonant configurations along the optical network can be accounted for. The total sum of all interferences affecting the bidirectional transmission that leads to an optical crosstalk-to-signal (C/S) ratio can be modeled as back-reflections through cascaded two-port networks for the downstream and upstream signals. This approach is simple, robust, efficient, and also accurate. Its accuracy is verified for simple system architectures and then applied to study more complicated cases. The results show its versatility to analyze a wide variety of bidirectional optical transmission systems.

  16. A 9 × 9 Matrix Representation of Birman-Wenzl-Murakami Algebra and Berry Phase in Yang-Baxter System

    Institute of Scientific and Technical Information of China (English)

    GOU Li-Dan; XUE Kang; WANG Gang-Cheng

    2011-01-01

    We present a 9 × 9 S-matrix and E-matrix. A representation of specialized Birman-Wenzl-Murakami algebra is obtained. Starting from the given braid group representation S-matrix, we obtain the trigonometric solution of Yang-Baxter equation. A unitary matrix R(x,φ1,φ2) is generated via the Yang-Baxterization approach. Then we construct a Yang-Baxter Hamiltonian through the unitary matrixR(x, φ1, φ2). Berry phase of this Yang-Baxter system is investigated in detail.

  17. Modeling and controller design of a wind energy conversion system including a matrix converter

    Science.gov (United States)

    Barakati, S. Masoud

    In this thesis, a grid-connected wind-energy converter system including a matrix converter is proposed. The matrix converter, as a power electronic converter, is used to interface the induction generator with the grid and control the wind turbine shaft speed. At a given wind velocity, the mechanical power available from a wind turbine is a function of its shaft speed. Through the matrix converter, the terminal voltage and frequency of the induction generator is controlled, based on a constant V/f strategy, to adjust the turbine shaft speed and accordingly, control the active power injected into the grid to track maximum power for all wind velocities. The power factor at the interface with the grid is also controlled by the matrix converter to either ensure purely active power injection into the grid for optimal utilization of the installed wind turbine capacity or assist in regulation of voltage at the point of connection. Furthermore, the reactive power requirements of the induction generator are satisfied by the matrix converter to avoid use of self-excitation capacitors. The thesis addresses two dynamic models: a comprehensive dynamic model for a matrix converter and an overall dynamical model for the proposed wind turbine system. The developed matrix converter dynamic model is valid for both steady-state and transient analyses, and includes all required functions, i.e., control of the output voltage, output frequency, and input displacement power factor. The model is in the qdo reference frame for the matrix converter input and output voltage and current fundamental components. The validity of this model is confirmed by comparing the results obtained from the developed model and a simplified fundamental-frequency equivalent circuit-based model. In developing the overall dynamic model of the proposed wind turbine system, individual models of the mechanical aerodynamic conversion, drive train, matrix converter, and squirrel-cage induction generator are developed

  18. PECM: prediction of extracellular matrix proteins using the concept of Chou's pseudo amino acid composition.

    Science.gov (United States)

    Zhang, Jian; Sun, Pingping; Zhao, Xiaowei; Ma, Zhiqiang

    2014-12-21

    The extracellular matrix proteins (ECMs) are widely found in the tissues of multicellular organisms. They consist of various secreted proteins, mainly polysaccharides and glycoproteins. The ECMs involve the exchange of materials and information between resident cells and the external environment. Accurate identification of ECMs is a significant step in understanding the evolution of cancer as well as promises wide range of potential applications in therapeutic targets or diagnostic markers. In this paper, an accurate computational method named PECM is proposed for identifying ECMs. Here, we explore various sequence-derived discriminative features including evolutionary information, predicted secondary structure, and physicochemical properties. Rather than simply combining the features which may bring information redundancy and unwanted noises, we use Fisher-Markov selector and incremental feature selection approach to search the optimal feature subsets. Then, we train our model by the technique of support vector machine (SVM). PECM achieves good prediction performance with the ACC scores about 86% and 90% on testing and independent datasets, which are competitive with the state-of-the-art ECMs prediction tools. A web-server named PECM which implements the proposed approach is freely available at http://59.73.198.144:8088/PECM/.

  19. A matrix transformation approach to H∞ control via static output feedback for input delay systems

    OpenAIRE

    Du, B; Shu, Z; Lam, J.

    2009-01-01

    This paper addresses the static output feedback (SOF) H∞ control for continuous-time linear systems with an unknown input delay from a novel perspective. New equivalent characterizations on the stability and H∞ performance of the closed-loop system are established in terms of nonlinear matrix inequalities with free parametrization matrices. These delay-dependent characterizations possess a special monotonic structure, which leads to linearized iterative computation. The effectiveness and meri...

  20. The Type II secretion system delivers matrix proteins for biofilm formation by Vibrio cholerae.

    Science.gov (United States)

    Johnson, Tanya L; Fong, Jiunn C; Rule, Chelsea; Rogers, Andrew; Yildiz, Fitnat H; Sandkvist, Maria

    2014-12-01

    Gram-negative bacteria have evolved several highly dedicated pathways for extracellular protein secretion, including the type II secretion (T2S) system. Since substrates secreted via the T2S system include both virulence factors and degradative enzymes, this secretion system is considered a major survival mechanism for pathogenic and environmental species. Previous analyses revealed that the T2S system mediates the export of ≥ 20 proteins in Vibrio cholerae, a human pathogen that is indigenous to the marine environment. Here we demonstrate a new role in biofilm formation for the V. cholerae T2S system, since wild-type V. cholerae was found to secrete the biofilm matrix proteins RbmC, RbmA, and Bap1 into the culture supernatant, while an isogenic T2S mutant could not. In agreement with this finding, the level of biofilm formation in a static microtiter assay was diminished in T2S mutants. Moreover, inactivation of the T2S system in a rugose V. cholerae strain prevented the development of colony corrugation and pellicle formation at the air-liquid interface. In contrast, extracellular secretion of the exopolysaccharide VPS, an essential component of the biofilm matrix, remained unaffected in the T2S mutants. Our results indicate that the T2S system provides a mechanism for the delivery of extracellular matrix proteins known to be important for biofilm formation by V. cholerae. Because the T2S system contributes to the pathogenicity of V. cholerae by secreting proteins such as cholera toxin and biofilm matrix proteins, elucidation of the molecular mechanism of T2S has the potential to lead to the development of novel preventions and therapies. PMID:25266381

  1. Passivity-Based Nonlinear Excitation Control of Power Systems with Structure Matrix Reassignment

    OpenAIRE

    Bing Chu; Yanhong Liu; Chunwen Li; Jianyong Li

    2013-01-01

    Passivity-based control is widely used in electronic circuit systems because it can utilize their internal structures to facilitate the controller design. In this paper, we first propose a dissipative Hamiltonian realization of power systems and discuss the disadvantages of the traditional passivity-based excitation controller. Then, a novel excitation controller is put forward to reassign the interconnection and dissipative matrix, and the corresponding Hamiltonian function. Simulation resul...

  2. Theoretical Studies of Active Power/angle Sub-matrix in Power Flow Jacobian for Power System Analysis

    Institute of Scientific and Technical Information of China (English)

    CAO Guo-yun; ZHANG Qing; CHUNG T S; CHEN Chen

    2008-01-01

    Properties of the active power/angle sub-matrix in the power flow Jacobian for power system analysis are studied. The sub-matrix is a dominant and irreducible matrix under very general conditions of power systems, so that it is invertible. Also the necessary conditions for its singularity are given. These theoretical rsuts can be used to clarify the ambiguous understanding of the sub-matrix in current literature, and also provide the theoretical foundations for the applications based on reduced power flow Jacobian. Numerical simulation on the IEEE 118-bus power system is used to illustrate our results.

  3. Virtual design software for mechanical system dynamics using transfer matrix method of multibody system and its application

    Directory of Open Access Journals (Sweden)

    Hai-gen Yang

    2015-09-01

    Full Text Available The complex mechanical systems such as high-speed trains, multiple launch rocket system, self-propelled artillery, and industrial robots are becoming increasingly larger in scale and more complicated in structure. Designing these products often requires complex model design, multibody system dynamics calculation, and analysis of large amounts of data repeatedly. In recent 20 years, the transfer matrix method of multibody system has been widely applied in engineering fields and welcomed at home and in abroad for the following features: without global dynamic equations of the system, low orders of involved system matrices, high computational efficiency, and high programming. In order to realize the rapid and visual simulation for complex mechanical system virtual design using transfer matrix method of multibody system, a virtual design software named MSTMMSim is designed and implemented. In the MSTMMSim, the transfer matrix method of multibody system is used as the solver for dynamic modeling and calculation; the Open CASCADE is used for solid geometry modeling. Various auxiliary analytical tools such as curve plot and animation display are provided in the post-processor to analyze and process the simulation results. Two numerical examples are given to verify the validity and accuracy of the software, and a multiple launch rocket system engineering example is given at the end of this article to show that the software provides a powerful platform for complex mechanical systems simulation and virtual design.

  4. Parameter identification of fractional order linear system based on Haar wavelet operational matrix.

    Science.gov (United States)

    Li, Yuanlu; Meng, Xiao; Zheng, Bochao; Ding, Yaqing

    2015-11-01

    Fractional order systems can be more adequate for the description of dynamical systems than integer order models, however, how to obtain fractional order models are still actively exploring. In this paper, an identification method for fractional order linear system was proposed. This is a method based on input-output data in time domain. The input and output signals are represented by Haar wavelet, and then fractional order systems described by fractional order differential equations are transformed into fractional order integral equations. Taking use of the Haar wavelet operational matrix of the fractional order integration, the fractional order linear system can easily be converted into a system of algebraic equation. Finally, the parameters of the fractional order system are determined by minimizing the errors between the output of the real system and that of the identified system. Numerical simulations, involving integral and fractional order systems, confirm the efficiency of the above methodology.

  5. Fuzzy Logic Control of Single Phase Matrix Converter Fed Induction Heating System

    Directory of Open Access Journals (Sweden)

    P. Umasankar

    2014-07-01

    Full Text Available This article represents the modeling and simulation of a Single Phase Matrix Converter (SPMC fed Induction Heating (IH system. The working principle and the control system using Fuzzy Logic Controller (FLC are elucidated in detail. The performance of the system and their harmonic content analysis of Single Phase Matrix Converter are carried out in MATLAB/Simulink environment. Pulse Width Modulation (PWM switching strategy by varying the duty cycle based on Fuzzy Logic Control is employed to obtain better performance for a constant voltage, constant frequency input supply for various output frequencies. The proposed control strategy results achieve low Total Harmonic Distortion (THD for various operating frequencies without large reactive storage elements.

  6. Fluorescence Properties of Eu3+/Gd3+/Citric Acid Mixed Complexes Doping in Silicon Rubber Matrix

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Series of doped rare earth complexes-EuxGd(1-x)(CA)3·nH2O (CA=citric acid) were synthesized. Some characterizations were taken for these complexes. The experimental results shows that the doped rare earth complexes have the best fluorescence property when the ratio of Eu and Gd is from 0.7 to 0.3. Silicon rubber-based composites were prepared by mechanical blending the EuxGd(1-x)(CA)3·nH2O and silicon rubber. Then, the fluorescent property of the composites was studied. It is found that the fluorescence intensity of the composites increase linearly with the contents of the rare earth complexes increasing.

  7. Low pressure process for continuous fiber reinforced polyamic acid resin matrix composite laminates

    Science.gov (United States)

    Druyun, Darleen A. (Inventor); Hou, Tan-Hung (Inventor); Kidder, Paul W. (Inventor); Reddy, Rakasi M. (Inventor); Baucom, Robert M. (Inventor)

    1994-01-01

    A low pressure processor was developed for preparing a well-consolidated polyimide composite laminate. Prepreg plies were formed from unidirectional fibers and a polyamic acid resin solution. Molding stops were placed at the sides of a matched metal die mold. The prepreg plies were cut shorter than the length of the mold in the in-plane lateral direction and were stacked between the molding stops to a height which was higher than the molding stops. The plies were then compressed to the height of the stops and heated to allow the volatiles to escape and to start the imidization reaction. After removing the stops from the mold, the heat was increased and 0 - 500 psi was applied to complete the imidization reaction. The heat and pressure were further increased to form a consolidated polyimide composite laminate.

  8. Numerical Modeling on Two phase Fluid flow in a Coupled Fracture-Skin-Matrix System

    Science.gov (United States)

    Valsala Kumari, R.; G, S. K.

    2015-12-01

    Multiphase flow modeling studies below the ground surface is very essential for designing suitable remediation strategies for contaminated aquifers and for the development of petroleum and geothermal reservoirs. Presence of fractured bedrock beneath the ground surface will make multiphase flow process more complex due to its highly heterogeneous nature. A major challenge in modeling flow within a fractured rock is to capture the interaction between the high permeability fracture and the low permeability rock-matrix. In some instances, weathering and mineral depositions will lead to formation of an additional layer named fracture-skin at the fracture-matrix interface. Porosity and permeability of fracture-skin may significantly vary from the adjacent rock matrix and this variation will result in different flow and transport behavior within the fracture-skin. In the present study, an attempt has been made to model simultaneous flow of two immiscible phases (water and LNAPL) in a saturated coupled fracture-skin-matrix system. A fully-implicit finite difference model has been developed to simulate the variation of pressure and saturation of fluid phases along the fracture and within the rock-matrix. Sensitivity studies have been done to analyze the effect of change of various fracture-skin parameters such as porosity, diffusion coefficient and thickness on pressure and saturation distribution of both wetting and non-wetting fluid phases. It can be concluded from the study that the presence of fracture-skin is significantly affecting the fluid flow at the fracture-matrix interface and it can also be seen from the study that the flow behavior of both fluid phases is sensitive to fracture-skin parameters.

  9. Eicosapentaenoic acid inhibits TNF-α-induced matrix metalloproteinase-9 expression in human keratinocytes, HaCaT cells

    International Nuclear Information System (INIS)

    Eicosapentaenoic acid (EPA) is an omega-3 (ω-3) polyunsaturated fatty acid (PUFA), which has anti-inflammatory and anti-cancer properties. Some reports have demonstrated that EPA inhibits NF-κB activation induced by tumor necrosis factor (TNF)-α or lipopolysaccharide (LPS) in various cells. However, its detailed mode of action is unclear. In this report, we investigated whether EPA inhibits the expression of TNF-α-induced matrix metalloproteinases (MMP)-9 in human immortalized keratinocytes (HaCaT). TNF-α induced MMP-9 expression by NF-κB-dependent pathway. Pretreatment of EPA inhibited TNF-α-induced MMP-9 expression and p65 phosphorylation. However, EPA could not affect IκB-α phosphorylation, nuclear translocation of p65, and DNA binding activity of NF-κB. EPA inhibited TNF-α-induced p65 phosphorylation through p38 and Akt inhibition and this inhibition was IKKα-dependent event. Taken together, we demonstrate that EPA inhibits TNF-α-induced MMP-9 expression through inhibition of p38 and Akt activation

  10. Comparison of the FFT/matrix inversion and system matrix techniques for higher-order probe correction in spherical near-field antenna measurements

    DEFF Research Database (Denmark)

    Pivnenko, Sergey; Nielsen, Jeppe Majlund; Breinbjerg, Olav;

    2011-01-01

    Two higher-order probe-correction techniques for spherical near-field antenna measurements are compared in details for the accuracy they provide and their computational cost. The investigated techniques are the FFT/matrix inversion and the system matrix inversion. Each of these techniques allows...... correction of general high-order probes, including non-symmetric dual-polarized antennas with independent ports. The investigation was carried out by processing with each technique the same measurement data for a challenging case with an antenna under test significantly offset from the center of rotation...

  11. Vesiculoviral matrix (M) protein occupies nucleic acid binding site at nucleoporin pair (Rae1∙Nup98)

    Energy Technology Data Exchange (ETDEWEB)

    Quan, Beili; Seo, Hyuk-Soo; Blobel, Günter; Ren, Yi [Rockefeller

    2014-07-01

    mRNA export factor 1 (Rae1) and nucleoporin 98 (Nup98) are host cell targets for the matrix (M) protein of vesicular stomatitis virus (VSV). How Rae1 functions in mRNA export and how M protein targets both Rae1 and Nup98 are not understood at the molecular level. To obtain structural insights, we assembled a 1:1:1 complex of M•Rae1•Nup98 and established a crystal structure at 3.15-Å resolution. We found that the M protein contacts the Rae1•Nup98 heterodimer principally by two protrusions projecting from the globular domain of M like a finger and thumb. Both projections clamp to the side of the β-propeller of Rae1, with the finger also contacting Nup98. The most prominent feature of the finger is highly conserved Methionine 51 (Met51) with upstream and downstream acidic residues. The complementary surface on Rae1 displays a deep hydrophobic pocket, into which Met51 fastens like a bolt, and a groove of basic residues on either side, which bond to the acidic residues of the finger. Notably, the M protein competed for in vitro binding of various oligonucleotides to Rae1•Nup98. We localized this competing activity of M to its finger using a synthetic peptide. Collectively, our data suggest that Rae1 serves as a binding protein for the phosphate backbone of any nucleic acid and that the finger of M mimics this ligand. In the context of mRNA export, we propose that a given mRNA segment, after having been deproteinated by helicase, is transiently reproteinated by Nup98-tethered Rae1. We suggest that such repetitive cycles provide cytoplasmic stopover sites required for ratcheting mRNA across the nuclear pore.

  12. Fuzzy Logic based Light Load Efficiency Improvement of Matrix Converter Based Wind Generation System

    Directory of Open Access Journals (Sweden)

    Vinod Kumar

    2007-06-01

    Full Text Available The paper describes a variable speed wind generation system where fuzzy logic principles are used for light load efficiency improvement and optimization. A squirrel cage induction generator feeds the power to an improved topology of matrix converter which pumps power to a utility grid or can supply to an autonomous system. The power factor at the interface with the grid is controlled by the matrix converter to ensure purely active power injection into the grid for optimal utilization of the installed wind turbine capacity. Furthermore, the reactive power requirements of the induction generator are satisfied by the matrix converter to avoid self-excitation capacitors. The generation system has fuzzy logic control with vector control in the inner loops. Fuzzy controller tracks the angular frequency with the wind velocity to extract the maximum power and programs the machine flux for light load efficiency improvement. The complete control system has been developed, analyzed, and validated by simulation study. Performances have then been evaluated in detail.

  13. Porous poly(DL-lactic acid) matrix film with antimicrobial activities for wound dressing application.

    Science.gov (United States)

    Chitrattha, Sasiprapa; Phaechamud, Thawatchai

    2016-01-01

    Poly(lactic acid) (PLA) is polymeric biomaterial that has been used for wound dressing due to its biodegradability and biocompatibility. However, PLA has some limitations including poor toughness, low degradation rate and high hydrophobicity. The aim of this study is to develop an antibiotic drug-loaded PLA porous film as wound dressing with antibacterial activity. PLA porous film was fabricated by temperature change technique using solvent casting method. Polyethylene glycol (PEG) 400 was added for improving the pore interconnectivity of film. Gentamicin sulfate (GS) or metronidazole (MZ) was incorporated into PLA porous films. PLA containing PEG 400 exhibited the more amorphous form than plain PLA film and contained 55.31 ± 2.85% porosity and 20 μm of the pore size which significantly improved the water vapor transmission rate, oxygen transmission rate, degradation rate and percentage of drug release, respectively. Drug-loaded porous films efficiently inhibited the bacteria growth. GS-loaded film inhibited Staphylococcus aureus, Proteus mirabilis, Pseudomonas aeruginosa, whereas MZ-loaded film inhibited Bacteroides fragilis and the sustainable antibacterial activity was attained for 7 days.

  14. Discrete time transfer matrix method for dynamics of multibody system with flexible beams moving in space

    Institute of Scientific and Technical Information of China (English)

    Xiao-Ting Rui; Edwin Kreuzer; Bao Rong; Bin He

    2012-01-01

    In this paper,by defining new state vectors and developing new transfer matrices of various elements moving in space,the discrete time transfer matrix method of multi-rigid-flexible-body system is expanded to study the dynamics of muhibody system with flexible beams moving in space.Formulations and numerical example of a rigidflexible-body three pendulums system moving in space are given to validate the method. Using the new method to study the dynamics of multi-rigid-flexible-body system mov ing in space,the global dynamics equations of system are not needed,the orders of involved matrices of the system are very low and the computational speed is high,irrespective of the size of the system.The new method is simple,straightforward,practical,and provides a powerful tool for multi-rigid-flexible-body system dynamics.

  15. Discrete time transfer matrix method for dynamics of multibody system with flexible beams moving in space

    Science.gov (United States)

    Rui, Xiao-Ting; Kreuzer, Edwin; Rong, Bao; He, Bin

    2012-04-01

    In this paper, by defining new state vectors and developing new transfer matrices of various elements moving in space, the discrete time transfer matrix method of multi-rigid-flexible-body system is expanded to study the dynamics of multibody system with flexible beams moving in space. Formulations and numerical example of a rigid-flexible-body three pendulums system moving in space are given to validate the method. Using the new method to study the dynamics of multi-rigid-flexible-body system moving in space, the global dynamics equations of system are not needed, the orders of involved matrices of the system are very low and the computational speed is high, irrespective of the size of the system. The new method is simple, straightforward, practical, and provides a powerful tool for multi-rigid-flexible-body system dynamics.

  16. Thermal front propagation in variable aperture fracture-matrix system: A numerical study

    Indian Academy of Sciences (India)

    Nikhil Bagalkot; G Suresh Kumar

    2015-04-01

    A numerical study on the effect of complex fracture aperture geometry on propagation of thermal front in a coupled single fracture-matrix system has been carried out. Sinusoidal and logarithmic functions have been used to capture the variation in fracture aperture. Modifications have been made to existing coupled partial differential governing equations to consider the variation of fracture aperture. Effect of temperature on the thermal and physical properties of rock have been incorporated. A fully implicit finite difference scheme has been used to discretize the coupled governing equations. Thermal convection, dispersion and conduction are the major transport processes within fracture, while conduction is the major transport process within rock matrix. The results suggest that variation of fracture aperture increases the heat transfer rate at the fracture-matrix interface. Sensitivity analysis on rock thermal conductivity and fracture aperture have been carried out. The results suggest that the heat transfer from rock matrix to fracture for the case of the parallel plate model is greatly dependent on the rock thermal conductivity (m) as compared to variable aperture model. Further, the thermal front propagation for both parallel plate model and variable aperture model is sensitive to changes in fracture aperture. The heat transfer rate at the interface is greater at smaller fracture apertures and decreases with increase in aperture.

  17. Fast and accurate generation method of PSF-based system matrix for PET reconstruction

    CERN Document Server

    Sun, Xiao-Li; Yun, Ming-Kai; Li, Dao-Wu; Gao, Juan; Li, Mo-Han; Chai, Pei; Tang, Hao-Hui; Zhang, Zhi-Ming; Wei, Long

    2016-01-01

    Positional single photon incidence response (P-SPIR) theory is researched in this paper to generate more accurate PSF-contained system matrix simply and quickly. The method has been proved highly effective to improve the spatial resolution by applying to the Eplus-260 primate PET designed by the Institute of High Energy Physics of the Chinese Academy of Sciences(IHEP). Simultaneously, to meet the clinical needs, GPU acceleration is put to use. Basically, P-SPIR theory takes both incidence angle and incidence position by crystal subdivision instead of only incidence angle into consideration based on Geant4 Application for Emission Tomography (GATE). The simulation conforms to the actual response distribution and can be completed rapidly within less than 1s. Furthermore,two-block penetration and normalization of the response probability are raised to fit the reality. With PSF obtained, the homogenization model is analyzed to calculate the spread distribution of bins within a few minutes for system matrix genera...

  18. The Real and Complex Hermitian Solutions to a System of Quaternion Matrix Equations with Applications

    Directory of Open Access Journals (Sweden)

    Shao-Wen Yu

    2012-01-01

    Full Text Available We establish necessary and sufficient conditions for the existence of and the expressions for the general real and complex Hermitian solutions to the classical system of quaternion matrix equations A1X=C1,XB1=C2, and  A3XA3*=C3. Moreover, formulas of the maximal and minimal ranks of four real matrices X1,X2,X3, and X4 in solution X=X1+X2i+X3j+X4k to the system mentioned above are derived. As applications, we give necessary and sufficient conditions for the quaternion matrix equations A1X=C1,XB1=C2,A3XA3*=C3, and  A4XA4*=C4 to have real and complex Hermitian solutions.

  19. Novel Control for Voltage Boosted Matrix Converter based Wind Energy Conversion System with Practicality

    Science.gov (United States)

    Kumar, Vinod; Joshi, Raghuveer Raj; Yadav, Dinesh Kumar; Garg, Rahul Kumar

    2016-06-01

    This paper presents the implementation and investigation of novel voltage boosted matrix converter (MC) based permanent magnet wind energy conversion system (WECS). In this paper, on-line tuned adaptive fuzzy control algorithm cooperated with reversed MC is proposed to yield maximum energy. The control system is implemented on a dSPACE DS1104 real time board. Feasibility of the proposed system has been experimentally verified using a laboratory 1.2 kW prototype of WECS under steady-state and dynamic conditions.

  20. Dominance-based Matrix algorithm for Knowledge Reductions in Incomplete Fuzzy Information System

    Directory of Open Access Journals (Sweden)

    Lixin Fan

    2013-07-01

    Full Text Available In this paper,definitions of knowledge granulation and rough entropy are proposed based on dominance relations in incomplete fuzzy information system, and important properties are obtained. It can be found that using the definitions can measure uncertainty of an attribute set in the incomplete fuzzy information systems. A matrix algorithm for attributes reduction is acquired in the systems. An example illustrates the validity of this algorithm, and results of compared with other existing methods show that the algorithm is an efficient tool for data mining.  

  1. Non-contact and Automatic Measurement of 2D Size with CCD Matrix and Computer System

    Institute of Scientific and Technical Information of China (English)

    ZHANG Ye; WANG Wen-sheng; GUO Yang-xue; SONG Hui-ying

    2003-01-01

    A measurement system with the CCD matrix and computer system is designed to test the 2D size of any shape workpieces automatically. In addition, the system adopts the method of the relative measurement which increases the precision and the velocity.More importantly,the precision can't be changed with the conditions of the temperature and air pressure.The experiments show that the relative precision of 0.002 9 and the absolute precision of 2.97 μm are obtained. The instrument may be used in the product line and make the testing on line possible.

  2. Passivity-Based Nonlinear Excitation Control of Power Systems with Structure Matrix Reassignment

    Directory of Open Access Journals (Sweden)

    Bing Chu

    2013-08-01

    Full Text Available Passivity-based control is widely used in electronic circuit systems because it can utilize their internal structures to facilitate the controller design. In this paper, we first propose a dissipative Hamiltonian realization of power systems and discuss the disadvantages of the traditional passivity-based excitation controller. Then, a novel excitation controller is put forward to reassign the interconnection and dissipative matrix, and the corresponding Hamiltonian function. Simulation results verify that the proposed controller can effectively improve the transient stability of the power system.

  3. Thin Film Heat Flux Sensor Development for Ceramic Matrix Composite (CMC) Systems

    Science.gov (United States)

    Wrbanek, John D.; Fralick, Gustave C.; Hunter, Gary W.; Zhu, Dongming; Laster, Kimala L.; Gonzalez, Jose M.; Gregory, Otto J.

    2010-01-01

    The NASA Glenn Research Center (GRC) has an on-going effort for developing high temperature thin film sensors for advanced turbine engine components. Stable, high temperature thin film ceramic thermocouples have been demonstrated in the lab, and novel methods of fabricating sensors have been developed. To fabricate thin film heat flux sensors for Ceramic Matrix Composite (CMC) systems, the rough and porous nature of the CMC system posed a significant challenge for patterning the fine features required. The status of the effort to develop thin film heat flux sensors specifically for use on silicon carbide (SiC) CMC systems with these new technologies is described.

  4. Robust control of uncertain multi-inventory systems via Linear Matrix Inequality

    OpenAIRE

    Bauso, D.; Giarré, L.; Pesenti, R.

    2007-01-01

    We consider a continuous time linear multi inventory system with unknown demands bounded within ellipsoids and controls bounded within ellipsoids or polytopes. We address the problem of "-stabilizing the inventory since this implies some reduction of the inventory costs. The main results are certain conditions under which "-stabilizability is possible through a saturated linear state feedback control. All the results are based on a Linear Matrix Inequalities (LMIs) approach and on some recent...

  5. Social Accounting Matrix and the System of National Accounts: an application

    OpenAIRE

    Santos, Susana

    2005-01-01

    Presented to the 15th International Input-Output Conference, held at the Renmin University of China, Beijing, on 28 June 2005 The purpose of this session is to show how the System of National Accounts (SNA) and the input- output (supply and use) tables are used to construct a Social Accounting Matrix (SAM). Based on the country's National Accounts, an aggregate SAM will be constructed for the Portuguese economy and their full consonance will be demonstrated by identifying both the items...

  6. Multi-ray-based system matrix generation for 3D PET reconstruction.

    Science.gov (United States)

    Moehrs, Sascha; Defrise, Michel; Belcari, Nicola; Guerra, Alberto Del; Bartoli, Antonietta; Fabbri, Serena; Zanetti, Gianluigi

    2008-12-01

    Iterative image reconstruction algorithms for positron emission tomography (PET) require a sophisticated system matrix (model) of the scanner. Our aim is to set up such a model offline for the YAP-(S)PET II small animal imaging tomograph in order to use it subsequently with standard ML-EM (maximum-likelihood expectation maximization) and OSEM (ordered subset expectation maximization) for fully three-dimensional image reconstruction. In general, the system model can be obtained analytically, via measurements or via Monte Carlo simulations. In this paper, we present the multi-ray method, which can be considered as a hybrid method to set up the system model offline. It incorporates accurate analytical (geometric) considerations as well as crystal depth and crystal scatter effects. At the same time, it has the potential to model seamlessly other physical aspects such as the positron range. The proposed method is based on multiple rays which are traced from/to the detector crystals through the image volume. Such a ray-tracing approach itself is not new; however, we derive a novel mathematical formulation of the approach and investigate the positioning of the integration (ray-end) points. First, we study single system matrix entries and show that the positioning and weighting of the ray-end points according to Gaussian integration give better results compared to equally spaced integration points (trapezoidal integration), especially if only a small number of integration points (rays) are used. Additionally, we show that, for a given variance of the single matrix entries, the number of rays (events) required to calculate the whole matrix is a factor of 20 larger when using a pure Monte-Carlo-based method. Finally, we analyse the quality of the model by reconstructing phantom data from the YAP-(S)PET II scanner. PMID:19001696

  7. The Expression of Bone Morphogenetic Protein 2 and Matrix Metalloproteinase 2 through Retinoic Acid Receptor Beta Induced by All-Trans Retinoic Acid in Cultured ARPE-19 Cells.

    Directory of Open Access Journals (Sweden)

    Zhenya Gao

    Full Text Available All-trans retinoic acid (ATRA plays an important role in ocular development. Previous studies found that retinoic acid could influence the metabolism of scleral remodeling by promoting retinal pigment epithelium (RPE cells to secrete secondary signaling factors. The purpose of this study was to investigate whether retinoic acid affected secretion of bone morphogenetic protein 2 (BMP-2 and matrix metalloproteinase 2 (MMP-2 and to explore the signaling pathway of retinoic acid in cultured acute retinal pigment epithelial 19 (ARPE-19 cells.The effects of ATRA (concentrations from 10-9 to 10-5 mol/l on the expression of retinoic acid receptors (RARs in ARPE-19 cells were examined at the mRNA and protein levels using reverse transcription-polymerase chain reaction (RT-PCR and western blot assay, respectively. The effects of treating ARPE-19 cells with ATRA concentrations ranging from 10-9 to 10-5 mol/l for 24 h and 48 h or with 10-6mol/l ATRA at different times ranging from 6h to 72h were assessed using real-time quantitative PCR (qPCR and enzyme-linked immunosorbent assay (ELISA. The contribution of RARβ-induced activation of ARPE-19 cells was confirmed using LE135, an antagonist of RARβ.RARβ mRNA levels significantly increased in the ARPE-19 cells treated with ATRA for 24h and 48h. These increases in RARβ mRNA levels were dose dependent (at concentrations of 10-9 to 10-5 mol/l with a maximum effect observed at 10-6 mol/l. There were no significant changes in the mRNA levels of RARα and RARγ. Western blot assay revealed that RARβ protein levels were increased significantly in a time-dependent manner in ARPE-19 cells treated with 10-6 mol/l ATRA from 12 h to 72 h, with a marked increase observed at 24 h and 48 h. The upregulation of RARβ and the ATRA-induced secretion in ARPE-19 cells could be inhibited by the RARβ antagonist LE135.ATRA induced upregulation of RARβ in ARPE-19 cells and stimulated these cells to secrete BMP-2 and MMP-2.

  8. The Expression of Bone Morphogenetic Protein 2 and Matrix Metalloproteinase 2 through Retinoic Acid Receptor Beta Induced by All-Trans Retinoic Acid in Cultured ARPE-19 Cells

    Science.gov (United States)

    Gao, Zhenya; Huo, Lijun; Cui, Dongmei; Yang, Xiao; Zeng, Junwen

    2016-01-01

    Purpose All-trans retinoic acid (ATRA) plays an important role in ocular development. Previous studies found that retinoic acid could influence the metabolism of scleral remodeling by promoting retinal pigment epithelium (RPE) cells to secrete secondary signaling factors. The purpose of this study was to investigate whether retinoic acid affected secretion of bone morphogenetic protein 2 (BMP-2) and matrix metalloproteinase 2 (MMP-2) and to explore the signaling pathway of retinoic acid in cultured acute retinal pigment epithelial 19 (ARPE-19) cells. Methods The effects of ATRA (concentrations from 10−9 to 10−5 mol/l) on the expression of retinoic acid receptors (RARs) in ARPE-19 cells were examined at the mRNA and protein levels using reverse transcription-polymerase chain reaction (RT-PCR) and western blot assay, respectively. The effects of treating ARPE-19 cells with ATRA concentrations ranging from 10−9 to 10−5 mol/l for 24 h and 48 h or with 10-6mol/l ATRA at different times ranging from 6h to 72h were assessed using real-time quantitative PCR (qPCR) and enzyme-linked immunosorbent assay (ELISA). The contribution of RARβ-induced activation of ARPE-19 cells was confirmed using LE135, an antagonist of RARβ. Results RARβ mRNA levels significantly increased in the ARPE-19 cells treated with ATRA for 24h and 48h. These increases in RARβ mRNA levels were dose dependent (at concentrations of 10−9 to 10−5 mol/l) with a maximum effect observed at 10−6 mol/l. There were no significant changes in the mRNA levels of RARα and RARγ. Western blot assay revealed that RARβ protein levels were increased significantly in a time-dependent manner in ARPE-19 cells treated with 10−6 mol/l ATRA from 12 h to 72 h, with a marked increase observed at 24 h and 48 h. The upregulation of RARβ and the ATRA-induced secretion in ARPE-19 cells could be inhibited by the RARβ antagonist LE135. Conclusion ATRA induced upregulation of RARβ in ARPE-19 cells and stimulated

  9. Fast and accurate computation of system matrix for area integral model-based algebraic reconstruction technique

    Science.gov (United States)

    Zhang, Shunli; Zhang, Dinghua; Gong, Hao; Ghasemalizadeh, Omid; Wang, Ge; Cao, Guohua

    2014-11-01

    Iterative algorithms, such as the algebraic reconstruction technique (ART), are popular for image reconstruction. For iterative reconstruction, the area integral model (AIM) is more accurate for better reconstruction quality than the line integral model (LIM). However, the computation of the system matrix for AIM is more complex and time-consuming than that for LIM. Here, we propose a fast and accurate method to compute the system matrix for AIM. First, we calculate the intersection of each boundary line of a narrow fan-beam with pixels in a recursive and efficient manner. Then, by grouping the beam-pixel intersection area into six types according to the slopes of the two boundary lines, we analytically compute the intersection area of the narrow fan-beam with the pixels in a simple algebraic fashion. Overall, experimental results show that our method is about three times faster than the Siddon algorithm and about two times faster than the distance-driven model (DDM) in computation of the system matrix. The reconstruction speed of our AIM-based ART is also faster than the LIM-based ART that uses the Siddon algorithm and DDM-based ART, for one iteration. The fast reconstruction speed of our method was accomplished without compromising the image quality.

  10. Twisted Six Dimensional Gauge Theories on Tori, Matrix Models,and Integrable Systems

    CERN Document Server

    Ganguli, S N; Gill, J A; Ganguli, Surya; Ganor, Ori J.; Gill, James A.

    2004-01-01

    We use the Dijkgraaf-Vafa technique to study massive vacua of 6D SU(N) SYM theories on tori with R-symmetry twists. One finds a matrix model living on the compactification torus with a genus-2 spectral curve whose Jacobian is closely related to a twisted four torus T in which the Seiberg-Witten curves of the theory are embedded. We also analyze R-symmetry twists in a bundle with nontrivial first Chern class which yields intrinsically 6D SUSY breaking and a novel matrix integral in which eigenvalues float in a sea of background charge. Next we analyze the underlying integrable system of the theory, whose phase space we show to be a system of N-1 points on T. We write down an explicit set of Poisson commuting Hamiltonians for this system for arbitrary N and use them to prove that equilbrium configurations with respect to all Hamiltonians correspond to points in moduli space where the Seiberg-Witten curve maximally degenerates to genus 2, thereby recovering the matrix model spectral curve. We also write down a c...

  11. A NEW BINARY POLYMERIC MATRIX SYSTEM FOR SUSTAINED RESEASE DRUG DELIVERY OF HIGHLY SOLUBLE DRUG: DILTIAZEM HYDROCHLORIDE

    Directory of Open Access Journals (Sweden)

    Gupta Khemchand

    2011-06-01

    Full Text Available The major objective of this study was to use pectin (high methoxylated in combination with guar gum to control the burst effect by promoting gelation and also to examine the release pattern of guar-pectin matrices. Guar gum has long been used to prepare matrix tablets. But its uncontrolled rate of hydration and initial slow gelling results into undesirable burst effect. Various combination of drug: polymer ratios were tried, out of which the ratio 1:2 yielded best results. The ratio of gaur: pectin in the polymer blend which gave best results was found to be 1:1.The effects of various diluents on the drug release were also determined at the same polymer level. The matrix tablet were prepared by wet granulation method using distilled water, were subjected to physical characterization and in vitro release studies. Release kinetics was evaluated by using USP apparatus type II at 100 rpm in 900 ml of acidic dissolution medium ( pH 1.2 for two hours, followed by 900 ml phosphate buffer dissolution medium (pH 6.8.The in-vitro drug release study revealed that (batch F3 combining pectin with guar gum sustained the drug release for 10 hours (87.54±2.36% release. Fitting the in-vitro drug release data to Korsmeyer-Peppas equation indicated that diffusion along with erosion could be the mechanism of drug release. At the same polymer level the order of release fell in the following manner lactose, avicel pH 101, starch and Emcompress®. It was concluded from the study that guar-pectin binary polymeric matrix system is an interesting alternative for preparing sustained release tablets.

  12. Matrix-product states for strongly correlated systems and quantum information processing

    International Nuclear Information System (INIS)

    This thesis offers new developments in matrix-product state theory for studying the strongly correlated systems and quantum information processing through three major projects: In the first project, we perform a systematic comparison between Wilson's numerical renormalization group (NRG) and White's density-matrix renormalization group (DMRG). The NRG method for solving quantum impurity models yields a set of energy eigenstates that have the form of matrix-product states (MPS). White's DMRG for treating quantum lattice problems can likewise be reformulated in terms of MPS. Thus, the latter constitute a common algebraic structure for both approaches. We exploit this fact to compare the NRG approach for the single-impurity Anderson model to a variational matrix-product state approach (VMPS), equivalent to single-site DMRG. For the latter, we use an ''unfolded'' Wilson chain, which brings about a significant reduction in numerical costs compared to those of NRG. We show that all NRG eigenstates (kept and discarded) can be reproduced using VMPS, and compare the difference in truncation criteria, sharp vs. smooth in energy space, of the two approaches. Finally, we demonstrate that NRG results can be improved upon systematically by performing a variational optimization in the space of variational matrix-product states, using the states produced by NRG as input. In the second project we demonstrate how the matrix-product state formalism provides a flexible structure to solve the constrained optimization problem associated with the sequential generation of entangled multiqubit states under experimental restrictions. We consider a realistic scenario in which an ancillary system with a limited number of levels performs restricted sequential interactions with qubits in a row. The proposed method relies on a suitable local optimization procedure, yielding an efficient recipe for the realistic and approximate sequential generation of any entangled multiqubit state. We give

  13. Matrix-product states for strongly correlated systems and quantum information processing

    Energy Technology Data Exchange (ETDEWEB)

    Saberi, Hamed

    2008-12-12

    This thesis offers new developments in matrix-product state theory for studying the strongly correlated systems and quantum information processing through three major projects: In the first project, we perform a systematic comparison between Wilson's numerical renormalization group (NRG) and White's density-matrix renormalization group (DMRG). The NRG method for solving quantum impurity models yields a set of energy eigenstates that have the form of matrix-product states (MPS). White's DMRG for treating quantum lattice problems can likewise be reformulated in terms of MPS. Thus, the latter constitute a common algebraic structure for both approaches. We exploit this fact to compare the NRG approach for the single-impurity Anderson model to a variational matrix-product state approach (VMPS), equivalent to single-site DMRG. For the latter, we use an ''unfolded'' Wilson chain, which brings about a significant reduction in numerical costs compared to those of NRG. We show that all NRG eigenstates (kept and discarded) can be reproduced using VMPS, and compare the difference in truncation criteria, sharp vs. smooth in energy space, of the two approaches. Finally, we demonstrate that NRG results can be improved upon systematically by performing a variational optimization in the space of variational matrix-product states, using the states produced by NRG as input. In the second project we demonstrate how the matrix-product state formalism provides a flexible structure to solve the constrained optimization problem associated with the sequential generation of entangled multiqubit states under experimental restrictions. We consider a realistic scenario in which an ancillary system with a limited number of levels performs restricted sequential interactions with qubits in a row. The proposed method relies on a suitable local optimization procedure, yielding an efficient recipe for the realistic and approximate sequential generation of any

  14. The composition of acids in bitumen and in products from saponification of kerogen: Investigation of their role as connecting kerogen and mineral matrix

    Energy Technology Data Exchange (ETDEWEB)

    Razvigorova, M.; Budinova, T.; Tsyntsarski, B.; Petrova, B. [Bulgarian Academy of Sciences, Institute of Organic Chemistry, 1113 Sofia, Acad. Bonchev Str., bl. 9 (Bulgaria); Ekinci, E. [ISIK University, Kumbaba Mevkii, 34980 Istanbul (Turkey); Atakul, H. [Istanbul Technical University, Department of Chemical Engineering, Maslak, 34469 Istanbul (Turkey)

    2008-11-03

    In order to obtain more information and to understand the nature of relation between organic and mineral matter in oil shales, the compositions of soluble bitumen fractions obtained by extraction from Bulgarian oil shales before and after demineralization with 10% HCl, concentrated HF, and a HF/HCl mixture were investigated. The four extracts were quantitatively examined by IR and {sup 1}H NMR spectroscopy. The investigation of isolated acidic material of the bitumen fractions showed that the fatty acids are present in bitumen fractions as free acids, esters and salts. The amount of free acids in bitumen is very small. The dominant part of bitumen acids is associated with mineral components of the oil shales as well as part of them is included in the mineral matrix, and can be separated only after deep demineralization. The kerogen of the oil shales, obtained after separation of the bitumen fractions and mineral components, was subjected to saponification in order to determine the amount of acids, bound as esters to the kerogen matrix. The major components found were n-carboxylic, {alpha},{omega}-di-carboxylic, and aromatic acids. The connection of kerogen with mineral components is accomplished by the participation of carboxylic and complicated ester bonds. Experimental data for the composition of bitumen acids give evidence that algae and terrestrial materials are initial sources in the formation of soluble organic matter of Bulgarian oil shale. (author)

  15. Effect of linear sorption on solute transport in a coupled fracture-matrix system with sinusoidal fracture geometry

    Directory of Open Access Journals (Sweden)

    N.Natarajan

    2010-10-01

    Full Text Available Modeling of solute transport through fractured rock is an important component of in many disciplines especially groundwater contamination and nuclear waste disposal. Several studies have been conducted on single rock fracture using parallel plate model and recently solute and thermal transport has been numerically modeled in the sinusoidal fracture matrix coupled system. The effect of linear sorption has been studied on the same. Results suggest the high matrix porosity and matrix diffusion coefficient enhance the sorption process and reduce the matrix diffusion of solutes. The velocity of the fluid reduces with increment in fracture aperture.

  16. A New Agile Radiating System Called Electromagnetic Band Gap Matrix Antenna

    Directory of Open Access Journals (Sweden)

    Hussein Abou Taam

    2014-01-01

    Full Text Available Civil and military applications are increasingly in need for agile antenna devices which respond to wireless telecommunications, radars, and electronic warfare requirements. The objective of this paper is to design a new agile antenna system called electromagnetic band gap (EBG matrix. The working principle of this antenna is based on the radiating aperture theory and constitutes the subject of an accepted CNRS patent. In order to highlight the interest and the originality of this antenna, we present a comparison between it and a classical patch array only for the (one-dimensional 1D configuration by using a rigorous full wave simulation (CST Microwave software. In addition, EBG matrix antenna can be controlled by specific synthesis algorithms. These algorithms use inside their; optimization loop an analysis procedure to evaluate the radiation pattern. The analysis procedure is described and validated at the end of this paper.

  17. Space Vector Modulation Based Direct Matrix Converter for Stand-Alone system

    Directory of Open Access Journals (Sweden)

    Chandra Sekhar Ajin Sekhar

    2014-02-01

    Full Text Available In this paper Permanent Magnet Synchronous Generator (PMSG is used for wind power generation in standalone system due to their feature of high efficiency and low maintenance cost, which was fed with smart direct matrix converter for direct AC-AC conversion, It provides sinusoidal output waveforms with minimal higher order harmonics and no sub harmonics and also it eliminate the usage of dc-link and other passive elements. Space vector modulation (SVM controlled technique is used for matrix converter switching which can eliminate the switching loses by selected switching states.Proposed work are often seen as a future concept for variable speed drives technology.The  proposed model for RL load was analysed and verified by varying the resistor and inductance value and analysed using MATLAB simulation.

  18. An explicit matrix formulation of the dynamical equations for flexible multibody systems - A recursive approach

    Science.gov (United States)

    Amirouche, F. M. L.; Xie, M.

    1993-01-01

    The dynamic simulation of complex rigid/flexible multibody systems relies greatly on the presentation and development of the equations of motion. To achieve computational speed in the execution and to further develop the control algorithms, the expressions involved in the kinematics and the subsequent coefficients associated with the equations of motion must be clearly defined. The intention of this paper is to develop a recursive formulation based on finite element method where all terms are presented in a matrix form. The methodology permits one to identify the coupling between rigid and flexible body motion, and build the necessary arrays for the application at hand. The equations of motion are based on Kane's equation and the general matrix representation for n bodies of its partial velocities and partial angular velocities. The algorithm developed is applied to a single two-link robot manipulator and the subsequent explicit equations of motion are presented.

  19. Development and evaluation of a hydrophilic matrix as a buccoadhesive system containing diclofenac sodium

    Directory of Open Access Journals (Sweden)

    Thaiz Cristina Wypych

    2011-10-01

    Full Text Available The aim of this work was to study the development and evaluation of a hydrolphilic matrix as a buccoadhesive system containing diclofenac sodium. Eleven formulations were prepared containing the following bioadhesive polymers: hydroxylpropylmethylcellulose, polycarbophil, guar gum and xanthan gum individually and in combination. All the formulations were evaluated for the swelling index, adhesive index, and the time of adhesive and drug release profile (%. The results showed that the formulations that presented the most swelling index were the F3 (PAA/GX and F6 (GG/GX. The smaller index swelling was for F1 (PAA/CM and F10 (HPCMC/CM. The F4 (PAA/HPMC formulation presented the best adhesive index and F10 (HPMC/CM the worst. F1 (PAA/CM was the best matrix hydrophilic adhesive for controlled release. The hydroxylpropylmethylcellulose, guar and xanthan gum when used individually presented low adhesiveness.

  20. Effect of adhesive matrix composition and terpinolene on indomethacin bioavailability in rats from transdermal therapeutic system.

    Science.gov (United States)

    Cal, Krzysztof; Sznitowska, Malgorzata; Janicki, Stanislaw

    2008-10-01

    Drug-in-adhesive matrix-type transdermal therapeutic systems for indomethacin (IND) were formulated and evaluated. Silicone and two types of polyacrylates were used as the bases of matrices. Terpinolene was used as a penetration enhancer. The physicochemical properties of matrices were determined. The bioavailability study of IND was performed in rats. The presence of IND in blood was demonstrated for each system. The calculated pharmacokinetics parameters for IND mainly depend on the solubility of IND in the adhesive layer. The positive influence of a penetration enhancer on IND bioavailability was observed only for one type of polyacrylate matrices. PMID:18777239

  1. A RELIABLE MATRIX CONVERTER FED INDUCTION MOTOR DRIVE SYSTEM BASED ON PARAMETER PLANE SYNTHESIS METHOD

    Directory of Open Access Journals (Sweden)

    Anubhav Agrawal

    2016-06-01

    Full Text Available The paper presents a novel technique for designing Proportional Integral (PI controller parameters for a reliable closed loop operation of Matrix Converter (MC fed Induction Motor Drive (IMD. Parameter plane synthesis method is used to find the stable region in PI parameter plane. Small signal stability of the system is tested by perturbation along the stable point. The frequency scanning technique is used to confirm the stability of the region in parametric plane. The theoretical investigations have been carried out for analyzing the steady state and transient behavior of the proposed drive system and compared with the conventional Ziegler-Nichols method.

  2. Robust control of uncertain multi-inventory systems via Linear Matrix Inequality

    CERN Document Server

    Bauso, D; Pesenti, R

    2007-01-01

    We consider a continuous time linear multi inventory system with unknown demands bounded within ellipsoids and controls bounded within ellipsoids or polytopes. We address the problem of "-stabilizing the inventory since this implies some reduction of the inventory costs. The main results are certain conditions under which "-stabilizability is possible through a saturated linear state feedback control. All the results are based on a Linear Matrix Inequalities (LMIs) approach and on some recent techniques for the modeling and analysis of polytopic systems with saturations.

  3. QUATERNION MATRIX IN NONLINEAR DYNAMICS OF HIGH-SPEED TRANSPORT SYSTEMS

    Directory of Open Access Journals (Sweden)

    V. V. Kravets

    2009-07-01

    Full Text Available The system of four quaternion matrices for presentation of main relationships of the theory of final rotation, kinematics and nonlinear dynamics of an asymmetric solid body in a three-dimensional space is presented. By means of application of equations in the form of Euler-Lagrange and the system of four quaternion matrices, the block-matrix model of nonlinear dynamics of a free asymmetric solid body in a three-dimensional space is built. The results obtained are approved. The offered algorithms are adapted directly to computing experiment.

  4. PERTURBATION TRANSFER MATRIX METHOD FOR EIGENDATA OF ONE-DIMENSIONAL STRUCTURAL SYSTEM WITH PARAMETER UNCERTAINTIES

    Institute of Scientific and Technical Information of China (English)

    刘保国; 殷学纲; 蹇开林; 吴永

    2003-01-01

    A general method based on Riccati transfer matrix is presented to calculate the2 nd order perturbations of eigendatas for one-dimensional structural system with parameteruncertainties. The method is applicable to both real and complex eigendatas of any one-dimensional structural system. The formulas for calculating the sensitivity derivatives ofeigendatas based on this method are also presented. The method is applied to theperturbation analysis for the eigendatas of a rotor with gyroscopic moment, and thedifferences between the perturbation results and the accurate calculating results are small.

  5. Stiffness of hyaluronic acid gels containing liver extracellular matrix supports human hepatocyte function and alters cell morphology.

    Science.gov (United States)

    Deegan, Daniel B; Zimmerman, Cynthia; Skardal, Aleksander; Atala, Anthony; Shupe, Thomas D

    2015-03-01

    Tissue engineering and cell based liver therapies have utilized primary hepatocytes with limited success due to the failure of hepatocytes to maintain their phenotype in vitro. In order to overcome this challenge, hyaluronic acid (HA) cell culture substrates were formulated to closely mimic the composition and stiffness of the normal liver cellular microenvironment. The stiffness of the substrate was modulated by adjusting HA hydrogel crosslinking. Additionally, the repertoire of bioactive molecules within the HA substrate was bolstered by supplementation with normal liver extracellular matrix (ECM). Primary human hepatocyte viability and phenotype were determined over a narrow physiologically relevant range of substrate stiffnesses from 600 to 4600Pa in both the presence and absence of liver ECM. Cell attachment, viability, and organization of the actin cytoskeleton improved with increased stiffness up to 4600Pa. These differences were not evident in earlier time points or substrates containing only HA. However, gene expression for the hepatocyte markers hepatocyte nuclear factor 4 alpha (HNF4α) and albumin significantly decreased on the 4600Pa stiffness at day 7 indicating that cells may not have maintained their phenotype long-term at this stiffness. Function, as measured by albumin secretion, varied with both stiffness and time in culture and peaked at day 7 at the 1200Pa stiffness, slightly below the stiffness of normal liver ECM at 3000Pa. Overall, gel stiffness affected primary human hepatocyte cell adhesion, functional marker expression, and morphological characteristics dependent on both the presence of liver ECM in gel substrates and time in culture. PMID:26569044

  6. Stiffness of hyaluronic acid gels containing liver extracellular matrix supports human hepatocyte function and alters cell morphology.

    Science.gov (United States)

    Deegan, Daniel B; Zimmerman, Cynthia; Skardal, Aleksander; Atala, Anthony; Shupe, Thomas D

    2015-03-01

    Tissue engineering and cell based liver therapies have utilized primary hepatocytes with limited success due to the failure of hepatocytes to maintain their phenotype in vitro. In order to overcome this challenge, hyaluronic acid (HA) cell culture substrates were formulated to closely mimic the composition and stiffness of the normal liver cellular microenvironment. The stiffness of the substrate was modulated by adjusting HA hydrogel crosslinking. Additionally, the repertoire of bioactive molecules within the HA substrate was bolstered by supplementation with normal liver extracellular matrix (ECM). Primary human hepatocyte viability and phenotype were determined over a narrow physiologically relevant range of substrate stiffnesses from 600 to 4600Pa in both the presence and absence of liver ECM. Cell attachment, viability, and organization of the actin cytoskeleton improved with increased stiffness up to 4600Pa. These differences were not evident in earlier time points or substrates containing only HA. However, gene expression for the hepatocyte markers hepatocyte nuclear factor 4 alpha (HNF4α) and albumin significantly decreased on the 4600Pa stiffness at day 7 indicating that cells may not have maintained their phenotype long-term at this stiffness. Function, as measured by albumin secretion, varied with both stiffness and time in culture and peaked at day 7 at the 1200Pa stiffness, slightly below the stiffness of normal liver ECM at 3000Pa. Overall, gel stiffness affected primary human hepatocyte cell adhesion, functional marker expression, and morphological characteristics dependent on both the presence of liver ECM in gel substrates and time in culture.

  7. Influence of purified multiwalled carbon nanotubes on the mechanical and morphological behavior in poly (L-lactic acid) matrix.

    Science.gov (United States)

    Leal, C V; Martinez, D S T; Más, B A; Alves, O L; Duek, E A R

    2016-06-01

    Poly (L-latic acid) (PLLA) is a bioresorbable polymer widely used as a biomaterial, but its fragility can limit its use. An alternative is to produce polymer nanocomposites, which can enhance the mechanical properties of polymeric matrix, resulting in a material with differentiated properties. In this work, PLLA based nanocomposites containing 0.25, 0.5 and 1.0wt% of purified multiwalled carbon nanotubes (p-MWCNTs) were prepared by the solvent casting method. The morphology and mechanical properties results show an improvement in strain at break for 0.25 and 0.5wt% p-MWCNTs and an increase in stiffness and elastic modulus for all compositions. Nanocomposites presented a p-MWCNTs agglomeration; however, there was a good stress transfer between PLLA and p-MWCNTs, which was confirmed by the increase in the hardness and elastic modulus. Atomic force microscopy analysis indicated an increase in roughness after nanotube addition. The in vitro biological study showed that PLLA/p-MWCNTs nanocomposites are cytocompatible with osteoblasts cells. The capacity of PLLA nanocomposites to stimulate osteogenesis was investigated by alkaline phosphatase (ALP) activity assay. Higher ALP activity was found on osteoblasts cultured on nanocomposites with 0.25 and 0.5wt% p-MWCNT compared to neat PLLA, confirming that PLLA cytocompatibility was improved on these compositions. Finally, our results showed that by a simple and inexpensive solvent casting method, it is possible to manufacture biofunctional nanocomposites devices with potential for orthopedic applications. PMID:27038896

  8. Evaluation of Influence of Various Polymers on Dissolution and Phase Behavior of Carbamazepine-Succinic Acid Cocrystal in Matrix Tablets

    Directory of Open Access Journals (Sweden)

    Majeed Ullah

    2015-01-01

    Full Text Available The aim of current study was to explore the influence of three commonly used polymers, that is, cellulosics and noncellulosics, for example, Methocel K4M, Kollidon VA/64, and Soluplus, on the phase disproportionation and drug release profile of carbamazepine-succinic acid (CBZ-SUC cocrystal at varying drug to polymer ratios (1 : 1 to 1 : 0.25 in matrix tablets. The polymorphic phase disproportionation during in-depth dissolution studies of CBZ-SUC cocrystals and its crystalline properties were scrutinized by X-ray powder diffractrometry and Raman spectroscopy. The percent drug release from HPMC formulations (CSH showed inverse relation with the concentration of polymer; that is, drug release increased with decrease in polymer concentration. On contrary, direct relation was observed between percent drug release and polymer concentrations of Kollidon VA 64/Soluplus (CSK, CSS. At similar polymer concentration, drug release from pure carbamazepine was slightly lower with HPMC formulations than that of cocrystal; however, opposite trend in release rate was observed with Kollidon VA/64 and Soluplus. The significant increase in dissolution rate of cocrystal occurred with Kollidon VA/64 and Soluplus at higher polymer concentration. Moreover, no phase change took place in Methocel and Kollidon formulations. No tablet residue was left for Soluplus formulation so the impact of polymer on cocrystal integrity cannot be predicted.

  9. Numerical modelling and experimental investigation of drug release from layered silicone matrix systems.

    Science.gov (United States)

    Snorradóttir, Bergthóra S; Jónsdóttir, Fjóla; Sigurdsson, Sven Th; Thorsteinsson, Freygardur; Másson, Már

    2013-07-16

    Medical devices and polymeric matrix systems that release drugs or other bioactive compounds are of interest for a variety of applications. The release of the drug can be dependent on a number of factors such as the solubility, diffusivity, dissolution rate and distribution of the solid drug in the matrix. Achieving the goal of an optimal release profile can be challenging when relying solely on traditional experimental work. Accurate modelling complementing experimentation is therefore desirable. Numerical modelling is increasingly becoming an integral part of research and development due to the significant advances in computer simulation technology. This work focuses on numerical modelling and investigation of multi-layered silicone matrix systems. A numerical model that can be used to model multi-layered systems was constructed and validated by comparison with experimental data. The model could account for the limited dissolution rate and effect of the drug distribution on the release profiles. Parametric study showed how different factors affect the characteristics of drug release. Multi-layered medical silicone matrices were prepared in special moulds, where the quantity of drug in each layer could be varied, and release was investigated with Franz-diffusion cell setup. Data for long-term release was fitted to the model and the full depletion of the system predicted. The numerical model constructed for this study, whose input parameters are the diffusion, effective dissolution rate and dimensional solubility coefficients, does not require any type of steady-state approximation. These results indicate that numerical model can be used as a design tool for development of controlled release systems such as drug-loaded medical devices.

  10. Evaluation of the thermodynamics of a four level system using canonical density matrix method

    Directory of Open Access Journals (Sweden)

    Awoga Oladunjoye A.

    2013-02-01

    Full Text Available We consider a four-level system with two subsystems coupled by weak interaction. The system is in thermal equilibrium. The thermodynamics of the system, namely internal energy, free energy, entropy and heat capacity, are evaluated using the canonical density matrix by two methods. First by Kronecker product method and later by treating the subsystems separately and then adding the evaluated thermodynamic properties of each subsystem. It is discovered that both methods yield the same result, the results obey the laws of thermodynamics and are the same as earlier obtained results. The results also show that each level of the subsystems introduces a new degree of freedom and increases the entropy of the entire system. We also found that the four-level system predicts a linear relationship between heat capacity and temperature at very low temperatures just as in metals. Our numerical results show the same trend.

  11. Grid Connected Wind Energy Conversion System Using Three Phase Matrix Converter

    Directory of Open Access Journals (Sweden)

    R.A. Priya

    2015-01-01

    Full Text Available A variable speed Wind Energy Conversion System (WECS with Permanent Magnet Synchronous Generator (PMSG connected to grid through Matrix Converter (MC is proposed in this study. Necessity for increased demand in electrical energy paved way for use of renewable energy sources, one of which is abundant wind energy available in ample. Various Wind Energy Conversion systems have been proposed over the decades, of which various topologies had been projected, where complex topologies are being in existence. Permanent magnet synchronous generator has substantial advantages over conventional generators like less weight and volume and exemption for separate excitation with high precision. The conventional system involves two stage of conversion involving rectification followed by inversion being coupled by a DC link capacitor before fed to a grid, which decreases the efficiency of the system due to power quality issue. To overcome this matrix converter can be utilized to transfer the power from generation stage to the grid; there by an AC-AC converter can transfer power from generator to the grid. The proposed system is designed and tested in MATALB/Simulink environment and the results are effective.

  12. Criticality and Excitation Gap in Quantum Systems: Applications of Continuous Matrix Product States in Imaginary Time

    CERN Document Server

    Tirrito, Emanuele; Ran, Shi-Ju

    2016-01-01

    We demonstrate an efficient method that allows for simultaneous determination of the ground state, low energy excitation properties and excitation gap in quantum many body systems. To this aim we first use the \\textit{ab-initio} optimization principle of tensor networks (TN), to show that the infinite density matrix renormalization group (iDMRG) in the real space is associated in a natural manner to the infinite time-evolving block decimation (iTEBD) implemented on a continuous matrix product state (MPS), and defined in imaginary time. We illustrate this association showing that the (imaginary) time matrix product state (MPS) in iTEBD reproduces accurately the properties of the two-dimensional (2D) classical Ising model, verifying in this way that the time MPS corresponds to a well-defined physical state. We apply then our scheme to the one-dimensional (1D) quantum Ising chain, where the time MPS is defined in continuous imaginary time. It is found that the time MPS at or close to the critical point is always...

  13. Realizing Low-Energy Classification Systems by Implementing Matrix Multiplication Directly Within an ADC.

    Science.gov (United States)

    Wang, Zhuo; Zhang, Jintao; Verma, Naveen

    2015-12-01

    In wearable and implantable medical-sensor applications, low-energy classification systems are of importance for deriving high-quality inferences locally within the device. Given that sensor instrumentation is typically followed by A-D conversion, this paper presents a system implementation wherein the majority of the computations required for classification are implemented within the ADC. To achieve this, first an algorithmic formulation is presented that combines linear feature extraction and classification into a single matrix transformation. Second, a matrix-multiplying ADC (MMADC) is presented that enables multiplication between an analog input sample and a digital multiplier, with negligible additional energy beyond that required for A-D conversion. Two systems mapped to the MMADC are demonstrated: (1) an ECG-based cardiac arrhythmia detector; and (2) an image-pixel-based facial gender detector. The RMS error over all multiplication performed, normalized to the RMS of ideal multiplication results is 0.018. Further, compared to idealized versions of conventional systems, the energy savings obtained are estimated to be 13× and 29×, respectively, while achieving similar level of performance. PMID:26849205

  14. Correlation matrix renormalization approximation for total-energy calculations of correlated electron systems

    Energy Technology Data Exchange (ETDEWEB)

    Yao, Y. X. [Ames Lab., Ames, IA (United States); Liu, Jun [Ames Lab., Ames, IA (United States); Wang, Cai-Zhuang [Ames Lab., Ames, IA (United States); Ho, Kai-Ming [Ames Lab., Ames, IA (United States)

    2014-01-23

    We generalized the commonly used Gutzwiller approximation for calculating the electronic structure and total energy of strongly correlated electron systems. In our method, the evaluation of one-body and two-body density matrix elements of the Hamiltonian is simplified using a renormalization approximation to achieve better scaling of the computational effort as a function of system size. To achieve a clear presentation of the concept and methodology, we describe the detailed formalism for a finite hydrogen system with minimal basis set. We applied the correlation matrix renormalization approximation approach to a H2 dimer and H8 cubic fragment with minimal basis sets, as well as a H2 molecule with a large basis set. The results compare favorably with sophisticated quantum chemical calculations. We believe our approach can serve as an alternative way to build up the exchange-correlation energy functional for an improved density functional theory description of systems with strong electron correlations.

  15. Adaptive Backstepping controller design and implementation for a matrix-converter-based IM drive system

    Directory of Open Access Journals (Sweden)

    R.R. Joshi

    2007-06-01

    Full Text Available A systematic controller design and implementation for a matrix-converter-based induction motor drive system is proposed. A nonlinear adaptive backstepping controller is proposed to improve the speed and position responses of the induction motor system. By using the proposed adaptive backstepping controller, the system can track a time-varying speed command and a time-varying position command well. Moreover, the system has a good load disturbance rejection capability. The realization of the controller is very simple. All of the control loops, including the current loop, speed loop and position loop, are implemented by a digital signal processor. Several experimental results are given to validate the theoretical analysis.

  16. Visualization and simulation of imbibition in the matrix-fracture system

    Energy Technology Data Exchange (ETDEWEB)

    Haghighi, M.; Shariat-Panahi, F. [Tehran Univ., (Iran, Islamic Republic of); Yortsos, Y.C. [Southern California Univ., CA (United States)

    2005-07-01

    In order to realistically predict ultimate oil recovery from naturally fractured reservoirs during water displacement, it is important to understand the flow behavior in the matrix-fracture systems at pore level. This study assessed some unclear theories that have been put forward regarding the production behavior of fractured oil reservoirs with water drive or during water injection. Primary imbibition at the pore level was visualized during 2 series of experiments, one without the effects of gravity at various capillary number values (Nc) and mobility ratios (M), and another with the effects of gravity at different Nc and constant M. In the experiments without gravity effects, it was observed that at low Nc the wetting fluid preferentially invaded the matrix. A critical capillary number was identified for the start of penetration in the fracture when the viscosity ratio was much less than one, and another was identified for the rate of propagation of the front in the fracture. The critical capillary numbers were in agreement with the results of a pore network simulation. Free imbibition in a fractured system was also examined and compared favorably with pore network simulation. All experiments under gravity effects were performed on 3 types of micromodels with different fracture orientations and gravity effects. The amount of oil recovery from the matrix fracture systems at various capillary numbers was determined and the results were compared with the model with no fracture. The results indicate that the amount of oil recovery by water displacement under the water-wet condition of the model is not very sensitive to the orientation of fractures. 21 refs., 3 tabs., 16 figs.

  17. Two-stage Voltage Closed Loop Control Scheme for Hybrid Excited Synchronous Generator-matrix Converter Generation System

    Institute of Scientific and Technical Information of China (English)

    SHI Mingming; ZHOU Bo; WEI Jiadan; MAO Yiran

    2012-01-01

    Matrix Converter (MC), a direct AC-AC converter which is capable of bidirectional power flow, unity input power factor control and efficiency improvement. Thus, it is more suitable for integration of motor machine and power electronics systems.

  18. Extracellular matrix molecules play diverse roles in the growth and guidance of central nervous system axons

    Directory of Open Access Journals (Sweden)

    M.A. Pires-Neto

    1999-05-01

    Full Text Available Axon growth and guidance represent complex biological processes in which probably intervene diverse sets of molecular cues that allow for the appropriate wiring of the central nervous system (CNS. The extracellular matrix (ECM represents a major contributor of molecular signals either diffusible or membrane-bound that may regulate different stages of neural development. Some of the brain ECM molecules form tridimensional structures (tunnels and boundaries that appear during time- and space-regulated events, possibly playing relevant roles in the control of axon elongation and pathfinding. This short review focuses mainly on the recognized roles played by proteoglycans, laminin, fibronectin and tenascin in axonal development during ontogenesis.

  19. Vector radiative transfer numerical model of coupled ocean-atmosphere system using matrix-operator method

    Institute of Scientific and Technical Information of China (English)

    HE XianQiang; PAN DeLu; BAI Yan; ZHU QianKun; GONG Fang

    2007-01-01

    A vector radiative transfer numerical model of the coupled ocean-atmosphere system is developed based on the matrix-operator method,which is named PCOART.Using the Fourier analysis,the vector radiative transfer equation (VRTE) is separated into a set of equations depending only on the observation zenith angle.Using the Gaussian-Quadrature method,VRTE is finally transferred into the matrix equation solved by the adding-doubling method.According to the reflective and refractive properties of the ocean-atmosphere interface,the vector radiative transfer numerical model of the ocean and atmosphere is coupled in PCOART.Compared with the exact Rayleigh scattering look-up tables of MODIS (Moderate-resolution Imaging Spectroradiometer),it is shown that PCOART is an exactly numerical model,and the processing methods of the multi-scattering and polarization are correct.Also,validated with the standard problems of the radiative transfer in water,it is shown that PCOART can be used to calculate the underwater radiative transfer problems.Therefore,PCOART is a useful tool for exactly calculating the vector radiative transfer of the coupled ocean-atmosphere system,which can be used to study the polarization properties of the radiance in the whole ocean-atmosphere system and the remote sensing of the atmosphere and ocean.

  20. Vector radiative transfer numerical model of coupled ocean-atmosphere system using matrix-operator method

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A vector radiative transfer numerical model of the coupled ocean-atmosphere system is developed based on the matrix-operator method, which is named PCOART. Using the Fourier analysis, the vector radiative transfer equation (VRTE) is separated into a set of equations depending only on the observa-tion zenith angle. Using the Gaussian-Quadrature method, VRTE is finally transferred into the matrix equation solved by the adding-doubling method. According to the reflective and refractive properties of the ocean-atmosphere interface, the vector radiative transfer numerical model of the ocean and at-mosphere is coupled in PCOART. Compared with the exact Rayleigh scattering look-up tables of MODIS (Moderate-resolution Imaging Spectroradiometer), it is shown that PCOART is an exactly numerical model, and the processing methods of the multi-scattering and polarization are correct. Also, validated with the standard problems of the radiative transfer in water, it is shown that PCOART can be used to calculate the underwater radiative transfer problems. Therefore, PCOART is a useful tool for exactly calculating the vector radiative transfer of the coupled ocean-atmosphere system, which can be used to study the polarization properties of the radiance in the whole ocean-atmosphere system and the remote sensing of the atmosphere and ocean.

  1. Discrete time transfer matrix method for dynamics of multibody system with real-time control

    Science.gov (United States)

    Rong, Bao; Rui, Xiaoting; Wang, Guoping; Yang, Fufeng

    2010-03-01

    By taking the control and feedback parameters into account in state vectors, defining new state vectors and deducing new transfer equations and transfer matrices for actuator, controlled element and feedback element, a new method named as the discrete time transfer matrix method for controlled multibody system (CMS) is developed to study dynamics of CMS with real-time control in this paper. This method does not need the global dynamics equations of system. It has the modeling flexibility, low order of system matrix, high computational efficiency, and is efficient for general CMS. Compared with the ordinary dynamics methods, the proposed method has more advantages for dynamics design and real-time control of a complex CMS. Adopting the PID adaptive controller and modal velocity feedback control on PZT actuators, and applying the proposed method and ordinary dynamics method, respectively, the tip trajectory tracking for a flexible manipulator is carried out. Formulations of the method as well as numerical simulation are given to validate the proposed method.

  2. Approximate Controllability of a Reaction-Diffusion System with a Cross-Diffusion Matrix and Fractional Derivatives on Bounded Domains

    OpenAIRE

    Badraoui Salah

    2010-01-01

    We study the following reaction-diffusion system with a cross-diffusion matrix and fractional derivatives in , in , on , , in where is a smooth bounded domain, , the diffusion matrix has semisimple and positive eigenvalues , , is an open nonempty set, and is the characteristic function of . Specifically, we prove that under some conditions over the coefficients , the semigroup generated by the linear operator of the system is exponentially stable, and under other c...

  3. Interface Stability of the SiC Particles/Fe Matrix Composite System

    Institute of Scientific and Technical Information of China (English)

    TANG Wenming; ZHENG Zhixiang; WU Yucheng; JIN Zhihao

    2006-01-01

    The interface reaction between the SiC particles (SiCp) and Fe was studied during sintering the SiCp reinforced Fe matrix composites at 1423 K for 1 h. In the composite having 3wt% (weight ratio) SiCp (the 3SiCp/Fe composite), the interface reaction products of Fe3Si, the carbon precipitates, and Fe3C or pearlite were generated. Fe3Si constructs the bright matrix of the reaction zone in the original situation of the SiCp. The carbon precipitates are randomly embedded in the reaction zone. Fe3C or pearlite exists at the grain boundaries of the Fe matrix. As increasing the SiCp concentration in the SiCp/Fe composite, the intensity of the interface reaction between SiCp and Fe increases. After the 10SiCp/Fe composite (having 10wt.% SiCp) sintered at 1423 K for 1 h, all of SiCp are decomposed, and replaced by the reaction zone composed of Fe3Si and the carbon precipitates. No Fe3C or pearlite was generated during the reaction. The effects of the techniques of oxidizing of SiCp, coating SiCp by interaction with the Cr powder, and alloying the Fe matrix by adding the Cr element on the interface stability of the SiCp/Fe composite system were also investigated, respectively. The oxide membrane and the coating layer on SiCp can inhibit the interface reaction between SiCp and Fe by isolating SiCp from the Fe matrix during sintering. The interface reaction does not occur in the 3SiCp/Fe-10Cr composite but in the 3SiCp/Fe-5Cr composite. In the SiCp/Fe-Cr alloy composites, the interface reaction between SiCp and the Fe-Cr alloys is weaker than that between SiCp and Fe. The Cr element behaves as a diluent, it causes a reduction in the interface reaction, which is proportional to the amount of the element added.

  4. Extracellular matrix-inspired growth factor delivery systems for bone regeneration

    Energy Technology Data Exchange (ETDEWEB)

    Martino, Mikaël M. [Osaka Univ. (Japan). Immunology Frontier Research Center; Briquez, Priscilla S. [Ecole Polytechnique Federale de Lausanne (Switzerland). Inst. of Bioengineering; Maruyama, Kenta [Osaka Univ. (Japan). Immunology Frontier Research Center; Hubbell, Jeffrey A. [Ecole Polytechnique Federale de Lausanne (Switzerland). Inst. of Bioengineering; Univ. of Chicago, IL (United States). Inst. for Molecular Engineering; Argonne National Lab. (ANL), Argonne, IL (United States)

    2015-04-17

    Growth factors are very promising molecules to enhance bone regeneration. However, their translation to clinical use has been seriously limited, facing issues related to safety and cost-effectiveness. These problems derive from the vastly supra-physiological doses of growth factor used without optimized delivery systems. Therefore, these issues have motivated the development of new delivery systems allowing better control of the spatio-temporal release and signaling of growth factors. Because the extracellular matrix (ECM) naturally plays a fundamental role in coordinating growth factor activity in vivo, a number of novel delivery systems have been inspired by the growth factor regulatory function of the ECM. After introducing the role of growth factors during the bone regeneration process, this review exposes different issues that growth factor-based therapies have encountered in the clinic and highlights recent delivery approaches based on the natural interaction between growth factor and the ECM.

  5. Observer design for matrix second order linear systems with uncertain disturbance input-a parametric approach

    Institute of Scientific and Technical Information of China (English)

    Wu Yunli; Li Zhibin; Duan Guangren

    2006-01-01

    A simple parametric approach to design a full-order observer for matrix second-order linear systems with uncertain disturbance input in the matrixsecond-order framework is proposed. The basic idea is to minimize the H2 norm of the transfer function from disturbance to estimation error using the design degrees of freedom provided by a parametric approach in the observer design. Besides the design parameters, the eigenvalues of the closed-loop system are also optimized within desired regions on the left-half of the complex plane. Using the proposed approach, additional specifications can be easily achieved. A spring-mass system is using to show the effect of the proposed approaches.

  6. Investigation of a matrix converter for contactless power transmission systems; Untersuchung eines Matrixumrichters fuer kontaktlose Energieuebertragungssysteme

    Energy Technology Data Exchange (ETDEWEB)

    Ecklebe, Andreas

    2009-05-22

    The publication discusses a three- to two-phase matrix converter for contactless power transmission systems. Based on relevant publications, possible resonance setups for contactless power transmission systems are investigated to begin with. An analysis of relevant parameters shows the differences between the various setups, but it also shows that for an investigation focusing on the feeding converter, simple modelling of the three investigated resonance setups is possible with the aid of a serial oscillating circuit. In consequence, it should be possible to apply the results also to the matrix converter with other serially resonant loads. The second part of the investigation focuses on the matrix converter. After a theoretical description, a combination von high-frequency control - e.g. bulk pulsing - and low-frequency pulsing patterns for setting the harmonics level of the grid currents is presented. The similarity to a conventional H bridge circuit enables an assessment of commutation and the identification of the necessary inverter states. These are characterized in that a bidirectional connection between the input system and each output phase is available at any time. The functioning of the commutation and of the inverter as a whole is proved by simulation in a first step, in which also the dynamic switching characteristics of the power semiconductors is taken into account. Finally, the results of laboratory measurements are presented and compared with the theoretical results. The laboratory setup consists of the power section of the matrix converter with input filters and modular gate drivers, a DSP/FPGA control system, and a contactless power transmission system with a current inverter and load on the secondary side. The investigation thus provides information on the use of the three-to-two phase matrix converter as an interesting alternative for feeding of contactless power transmission systems and other serially resonant loads. (orig.) [German] Diese

  7. Investigation of a matrix converter for contactless power transmission systems; Untersuchung eines Matrixumrichters fuer kontaktlose Energieuebertragungssysteme

    Energy Technology Data Exchange (ETDEWEB)

    Ecklebe, Andreas

    2009-05-22

    The publication discusses a three- to two-phase matrix converter for contactless power transmission systems. Based on relevant publications, possible resonance setups for contactless power transmission systems are investigated to begin with. An analysis of relevant parameters shows the differences between the various setups, but it also shows that for an investigation focusing on the feeding converter, simple modelling of the three investigated resonance setups is possible with the aid of a serial oscillating circuit. In consequence, it should be possible to apply the results also to the matrix converter with other serially resonant loads. The second part of the investigation focuses on the matrix converter. After a theoretical description, a combination von high-frequency control - e.g. bulk pulsing - and low-frequency pulsing patterns for setting the harmonics level of the grid currents is presented. The similarity to a conventional H bridge circuit enables an assessment of commutation and the identification of the necessary inverter states. These are characterized in that a bidirectional connection between the input system and each output phase is available at any time. The functioning of the commutation and of the inverter as a whole is proved by simulation in a first step, in which also the dynamic switching characteristics of the power semiconductors is taken into account. Finally, the results of laboratory measurements are presented and compared with the theoretical results. The laboratory setup consists of the power section of the matrix converter with input filters and modular gate drivers, a DSP/FPGA control system, and a contactless power transmission system with a current inverter and load on the secondary side. The investigation thus provides information on the use of the three-to-two phase matrix converter as an interesting alternative for feeding of contactless power transmission systems and other serially resonant loads. (orig.) [German] Diese

  8. Parity effects in eigenvalue correlators, parametric and crossover correlators in random matrix models: Application to mesoscopic systems

    Indian Academy of Sciences (India)

    N Deo

    2002-02-01

    This paper summarizes some work that I have been doing on eigenvalue correlators of random matrix models which show some interesting behavior. First we consider matrix models with gaps in their spectrum or density of eigenvalues. The density–density correlators of these models depend on whether , where is the size of the matrix, takes even or odd values. The fact that this dependence persists in the large thermodynamic limit is an unusual property and may have consequences in the study of one electron effects in mesoscopic systems. Secondly, we study the parametric and cross correlators of the Harish Chandra–Itzykson–Zuber matrix model. The analytic expressions determine how the correlators change as a parameter (e.g. the strength of a perturbation in the Hamiltonian of the chaotic system or external magnetic field on a sample of material) is varied. The results are relevant for the conductance fluctuations in disordered mesoscopic systems.

  9. In the presence of danger:the extracellular matrix defensive response to central nervous system injury

    Institute of Scientific and Technical Information of China (English)

    Lyn B. Jakeman; Kent E. Williams; Bryan Brautigam

    2014-01-01

    Glial cells in the central nervous system (CNS) contribute to formation of the extracellular matrix, which provides adhesive sites, signaling molecules, and a diffusion barrier to enhance efifcient neurotransmission and axon potential propagation. In the normal adult CNS, the extracellular matrix (ECM) is relatively stable except in selected regions characterized by dynamic remodel-ing. However, after trauma such as a spinal cord injury or cortical contusion, the lesion epicenter becomes a focus of acute neuroinlfammation. The activation of the surrounding glial cells leads to a dramatic change in the composition of the ECM at the edges of the lesion, creating a perile-sion environment dominated by growth inhibitory molecules and restoration of the peripheral/central nervous system border. An advantage of this response is to limit the invasion of damaging cells and diffusion of toxic molecules into the spared tissue regions, but this occurs at the cost of inhibiting migration of endogenous repair cells and preventing axonal regrowth. The following review was prepared by reading and discussing over 200 research articles in the ifeld published in PubMed and selecting those with signiifcant impact and/or controversial points. This article highlights structural and functional features of the normal adult CNS ECM and then focuses on the reactions of glial cells and changes in the perilesion border that occur following spinal cord or contusive brain injury. Current research strategies directed at modifying the inhibitory perile-sion microenvironment without eliminating the protective functions of glial cell activation are discussed.

  10. Temporal moment analysis of solute transport in a coupled fracture-skin-matrix system

    Indian Academy of Sciences (India)

    V Renu; G Suresh Kumar

    2014-04-01

    In the present study, method of temporal moments has been used to analyse the transport characteristics of reactive solute along fracture in a coupled fracture-skin-matrix system. In order to obtain the concentration distribution within the fracture, a system of coupled partial differential equations for fracture, fractureskin and rock-matrix has been solved numerically in a pseudo two-dimensional domain using implicit finite difference method. Subsequently, lower order temporal moments of solute have been computed from the concentration distribution to analyse the transport characteristics of solutes in the fracture. This study has been done by considering an inlet boundary condition of constant continuous source in a single fracture. The effect of various fracture-skin parameters like porosity, thickness and diffusion coefficient on the transport of solutes have been studied by doing sensitivity analyses. The effect of nonlinear sorption and radioactive decay of solutes have also been analysed by carrying out simulations for different sorption intensities and decay constants. Numerical results suggested that the presence of fracture-skin significantly influences the transport characteristics of reactive solutes along the fracture.

  11. A suppository-base-matrix tablet for time-dependent colon-specific delivery system

    Directory of Open Access Journals (Sweden)

    Meijuan Zou

    2014-09-01

    Full Text Available Our research has focused on the main design features and release performances of time-dependent colon-specific (TDCS delivery tablets, which relies on the relative constancy that is observed in the small intestinal transit time of dosage forms. But inflammatory bowel disease(IBD)can affect the transit time, and usually results in watery stool. Compared to the TDCS and wax-matrix TDCS tablet, a promising time-dependent colon-specific delivery system was investigated. In our study, a suppository-base-matrix coated tablet was evaluated. Water soluble suppository-base helps the expansion of tablet, facilitates uniform film dissolution and achives high osmotic pressure. Combining the expansion of carboxymethyl starch sodium (CMS-Na and the moisture absorption of NaCl, the coated TDCS tablet obtained a burst and targeted drug delivery system. A very good correlation between in vitro drug release and in vivo outcome was observed. This TDCS coated tablet provides a promising strategy to control drug release to the desired lower gastrointestinal region.

  12. Reduction of Inflammatory Responses and Enhancement of Extracellular Matrix Formation by Vanillin-Incorporated Poly(Lactic-co-Glycolic Acid) Scaffolds

    OpenAIRE

    Lee, Yujung; Kwon, JeongIl; Khang, Gilson; Lee, Dongwon

    2012-01-01

    Vanillin is one of the major components of vanilla, a commonly used flavoring agent and preservative and is known to exert potent antioxidant and anti-inflammatory activities. In this work, vanillin-incorporated poly(lactic-co-glycolic acid) (PLGA) films and scaffolds were fabricated to evaluate the effects of vanillin on the inflammatory responses and extracellular matrix (ECM) formation in vitro and in vivo. The incorporation of vanillin to PLGA films induced hydrophilic nature, resulting i...

  13. AN AMPEROMETRIC BIOSENSOR BASED ON COVALENT IMMOBILIZATION OF ASCORBATE OXIDASE ON BIOCOMPATIABLE AND LOW-TOXIC POLY(THIOPHENE-3-ACETIC ACID) MATRIX

    Institute of Scientific and Technical Information of China (English)

    Dong Li; Yang-ping Wen; Jing-kun Xu; Hao-hua He; Ming Liu

    2012-01-01

    The biocompatiable and low-toxic poly(thiophene-3-acetic acid) (PTAA) matrix was successfully electrosynthesized in ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate (BmimPF6) in comparison with the electrosynthesis of PTAA matrix in acetonitrile (ACN).Ascorbate oxidase (AO) was used as a model for the development and application of biosensor.Vitamin C (VC) biosensors were facilely fabricated by the covalent immobilization of AO molecules on PTAA matrices electrosynthesized in ACN containing tetrabutylammonium tetrafluoroborate and BmimPF6,respectively.Electrochemical impedance spectroscopy,scanning electron microscopy and FTIR spectroscopy indicated that AO molecules were covalently immobilized on PTAA matrices.Parameters of the as-obtained biosensors such as working potential,pH and temperature have been optimized.The amperometric biosensor based on PTAA matrix electrosynthesized in BmimPF6 exhibited wider linear range,lower detection limit,higher sensitivity and bioaffinity,and better operational and storage stability than that electrosynthesized in ACN under optimal conditions.The as-obtained biosensor based on PTAA matrix electrosynthesized in BmimPF6 was employed for the detection of VC content in commercial juices,and the result was close to the data given by manufacturers.Excellent results indicate that the PTAA matrix electrosynthesized in ionic liquid is a promising platform for the covalent immobilization of biologically-active species and the development of biosensors.

  14. Brain docosahexaenoic acid (DHA levels of young rats are related to alpha-linolenic acid (ALA levels and fat matrix of the diet: impact of dairy fat*

    Directory of Open Access Journals (Sweden)

    Delplanque Bernadette

    2011-11-01

    Full Text Available Dososahexaenoate (DHA is highly concentrated in mammalian nervous and visual systems and its deficiency during gestation, lactation and early life, could have dramatic impacts on brain functions and mental health. Achieving an appropriate DHA status in the neonatal brain is an important goal of neonatal nutrition. We evaluated how a-linolenic acid (ALA provided by different dietary fat matrices improved DHA content in the brains of both young male and female rats. Young rats born from dams fed during gestation and lactation with a low ALA diet (0.4% of fatty acids were subjected for 6 weeks after weaning to an anhydrous dairy fat blend-based diet that provided 1.5% ALA or to a palm oil blend-based diet that provided the same ALA level: either 1.5% ALA or 1.5% ALA and 0.12% DHA with 0.4% arachidonic acid (ARA. With each diet the n-6/ n-3 ratio was similar (10 to follow the values generally recommended for infant formula. Fatty acids analysis in whole brain showed that 1.5% ALA dairy fat blend was superior to both 1.5% ALA palm-oil blends, supplemented or not with dietary DHA, for increasing brain DHA. Females compared to males had significantly higher brain DHA with the 1.5% ALA palm-blend diet, but the dietary supplementation with DHA smoothed the differences by a specific increase of males DHA brain. In conclusion, dairy fat blend enriched with ALA appear to be an interesting strategy for achieving optimal DHA levels in the brain of post-weaning rats. Inclusion of dairy fat in infant formulas should be reconsidered.

  15. Federal Aviation Administration (FAA airworthiness certification for ceramic matrix composite components in civil aircraft systems

    Directory of Open Access Journals (Sweden)

    Gonczy Stephen T.

    2015-01-01

    Full Text Available Ceramic matrix composites (CMCs are being designed and developed for engine and exhaust components in commercial aviation, because they offer higher temperature capabilities, weight savings, and improved durability compared to metals. The United States Federal Aviation Administration (FAA issues and enforces regulations and minimum standards covering the safe manufacture, operation, and maintenance of civil aircraft. As new materials, these ceramic composite components will have to meet the certification regulations of the FAA for “airworthiness”. The FAA certification process is defined in the Federal Aviation Regulations (Title 14 of the Code of Federal Regulations, FAA policy statements, orders, advisory circulars, technical standard orders, and FAA airworthiness directives. These regulations and documents provide the fundamental requirements and guidelines for design, testing, manufacture, quality assurance, registration, operation, inspection, maintenance, and repair of aircraft systems and parts. For metallic parts in aircraft, the FAA certification and compliance process is well-established for type and airworthiness certification, using ASTM and SAE standards, the MMPDS data handbook, and FAA advisory circulars. In a similar manner for polymer matrix composites (PMC, the PMC industry and the FAA have jointly developed and are refining parallel guidelines for polymer matrix composites (PMCs, using guidance in FAA circulars and the CMH-17 PMC handbook. These documents discuss design methods and codes, material testing, property data development, life/durability assessment, production processes, QA procedures, inspection methods, operational limits, and repairs for PMCs. For ceramic composites, the FAA and the CMC and aerospace community are working together (primarily through the CMH-17 CMC handbook to define and codify key design, production, and regulatory issues that have to be addressed in the certification of CMC components in

  16. Recent Applications Of Metal Matrix Composites In Precision Instruments And Optical Systems

    Science.gov (United States)

    Mohn, Walter R.; Vukobratovich, Daniel

    1988-02-01

    This paper describes three unique metal matrix composite (MMC) material systems that have been developed for use in dimensionally stable platforms, precision mechanical systems, and lightweight reflective optics. These engineered materials, consisting of aluminum alloys reinforced with fine particles of silicon carbide, offer distinctive performance advantages over conventional metals, including greater specific stiffness, higher strength, and better resistance to compressive microcreep. Weighing about the same as aluminum, certain grades of these MMC materials are isotropic and have excellent thermal conductivity, and they can be tailored to match the coefficients of thermal expansion of other materials, including beryllium, stainless steel, and electroless nickel. Such flexibilities in establishing material properties and characteristics present new opportunities to the designer in producing weight-critical, precision hardware. Practical applications of MMC materials in advanced guidance equipment and lightweight optical assemblies are presented and discussed.

  17. Continuous-flow free acid monitoring method and system

    Science.gov (United States)

    Strain, J.E.; Ross, H.H.

    1980-01-11

    A free acid monitoring method and apparatus is provided for continuously measuring the excess acid present in a process stream. The disclosed monitoring system and method is based on the relationship of the partial pressure ratio of water and acid in equilibrium with an acid solution at constant temperature. A portion of the process stream is pumped into and flows through the monitor under the influence of gravity and back to the process stream. A continuous flowing sample is vaporized at a constant temperature and the vapor is subsequently condensed. Conductivity measurements of the condensate produces a nonlinear response function from which the free acid molarity of the sample process stream is determined.

  18. Simplified LCA and matrix methods in identifying the environmental aspects of a product system.

    Science.gov (United States)

    Hur, Tak; Lee, Jiyong; Ryu, Jiyeon; Kwon, Eunsun

    2005-05-01

    In order to effectively integrate environmental attributes into the product design and development processes, it is crucial to identify the significant environmental aspects related to a product system within a relatively short period of time. In this study, the usefulness of life cycle assessment (LCA) and a matrix method as tools for identifying the key environmental issues of a product system were examined. For this, a simplified LCA (SLCA) method that can be applied to Electrical and Electronic Equipment (EEE) was developed to efficiently identify their significant environmental aspects for eco-design, since a full scale LCA study is usually very detailed, expensive and time-consuming. The environmentally responsible product assessment (ERPA) method, which is one of the matrix methods, was also analyzed. Then, the usefulness of each method in eco-design processes was evaluated and compared using the case studies of the cellular phone and vacuum cleaner systems. It was found that the SLCA and the ERPA methods provided different information but they complemented each other to some extent. The SLCA method generated more information on the inherent environmental characteristics of a product system so that it might be useful for new design/eco-innovation when developing a completely new product or method where environmental considerations play a major role from the beginning. On the other hand, the ERPA method gave more information on the potential for improving a product so that it could be effectively used in eco-redesign which intends to alleviate environmental impacts of an existing product or process.

  19. Simplified LCA and matrix methods in identifying the environmental aspects of a product system.

    Science.gov (United States)

    Hur, Tak; Lee, Jiyong; Ryu, Jiyeon; Kwon, Eunsun

    2005-05-01

    In order to effectively integrate environmental attributes into the product design and development processes, it is crucial to identify the significant environmental aspects related to a product system within a relatively short period of time. In this study, the usefulness of life cycle assessment (LCA) and a matrix method as tools for identifying the key environmental issues of a product system were examined. For this, a simplified LCA (SLCA) method that can be applied to Electrical and Electronic Equipment (EEE) was developed to efficiently identify their significant environmental aspects for eco-design, since a full scale LCA study is usually very detailed, expensive and time-consuming. The environmentally responsible product assessment (ERPA) method, which is one of the matrix methods, was also analyzed. Then, the usefulness of each method in eco-design processes was evaluated and compared using the case studies of the cellular phone and vacuum cleaner systems. It was found that the SLCA and the ERPA methods provided different information but they complemented each other to some extent. The SLCA method generated more information on the inherent environmental characteristics of a product system so that it might be useful for new design/eco-innovation when developing a completely new product or method where environmental considerations play a major role from the beginning. On the other hand, the ERPA method gave more information on the potential for improving a product so that it could be effectively used in eco-redesign which intends to alleviate environmental impacts of an existing product or process. PMID:15829365

  20. 一矩阵方程组的反射解%Reflexive solution to a system of matrix equations

    Institute of Scientific and Technical Information of China (English)

    常海霞; 王卿文

    2007-01-01

    We derive necessary and sufficient conditions for the existence and an expression of the (anti)reflexive solution with respect to the nontrivial generalized reflection matrix P to the system of complex matrix equations AX = B and XC = D.The explicit solutions of the approximation problem minX∈φ‖X- E‖F was given, where E is a given complex matrix and o is it was pointed that some results in a recent paper are special cases of this paper.

  1. Dry Arthroscopy With a Retraction System for Matrix-Aided Cartilage Repair of Patellar Lesions

    OpenAIRE

    Sadlik, Boguslaw; Wiewiorski, Martin

    2014-01-01

    Several commercially available cartilage repair techniques use a natural or synthetic matrix to aid cartilage regeneration (e.g., autologous matrix–induced chondrogenesis or matrix-induced cartilage implantation). However, the use of matrix-aided techniques during conventional knee joint arthroscopy under continuous irrigation is challenging. Insertion and fixation of the matrix can be complicated by the presence of fluid and the confined patellofemoral joint space with limited access to the ...

  2. The {P,Q,k+1}-Reflexive Solution to System of Matrix Equations AX=C, XB=D

    Directory of Open Access Journals (Sweden)

    Chang-Zhou Dong

    2015-01-01

    Full Text Available Let P∈Cm×m and Q∈Cn×n be Hermitian and {k+1}-potent matrices; that is, Pk+1=P=P⁎ and Qk+1=Q=Q⁎, where ·⁎ stands for the conjugate transpose of a matrix. A matrix X∈Cm×n is called {P,Q,k+1}-reflexive (antireflexive if PXQ=X (PXQ=-X. In this paper, the system of matrix equations AX=C and XB=D subject to {P,Q,k+1}-reflexive and antireflexive constraints is studied by converting into two simpler cases: k=1 and k=2. We give the solvability conditions and the general solution to this system; in addition, the least squares solution is derived; finally, the associated optimal approximation problem for a given matrix is considered.

  3. ABOUT THE INFORMATIZATION MANAGING OF THE PRODUCTION SYSTEM BASED ON THE MATRIX MODEL

    Directory of Open Access Journals (Sweden)

    Aleksandr V. Romanenko

    2016-06-01

    Full Text Available Introduction. The problem of formation and information management systems management of manufacturing system businesses is analyzed in the article. Existing schemes of the Russian economy increased demands for its efficiency. Stability integrative model business entity lifecycle requires a search for solutions based on new technologies in the organization and operation of information management systems. Results. On the basis of the analysis of their importance for sustainability of the entity components of its life cycle conclusions are made about the applicability of the matrix model to the production system management. Contradiction in the application of this management model are solved by separating the information on the basis of the state of product and process state. This division contributes to a better organization of the distribution of responsibility between the profit centers and cost centers. As an indicator of the efficiency of profit centers, it is proposed to use the ratio revenue net from the sale of products to the current value of the planned costs of its production. To assess the effectiveness of cost centers used index that is similar to profitability of fixed assets taking into account the cost of resources utilized by each cost center separately. Discussion and Conclusions. We analyze the relationship between goals management of the production system with the role of profit centers and cost centers. The proposed basis of the formation model information ensures the management of the production system, contributing to improve the quality of managerial decisions in implementing the competitive advantages of business entity.

  4. Evolutionary systems biology of amino acid biosynthetic cost in yeast.

    Directory of Open Access Journals (Sweden)

    Michael D Barton

    Full Text Available Every protein has a biosynthetic cost to the cell based on the synthesis of its constituent amino acids. In order to optimise growth and reproduction, natural selection is expected, where possible, to favour the use of proteins whose constituents are cheaper to produce, as reduced biosynthetic cost may confer a fitness advantage to the organism. Quantifying the cost of amino acid biosynthesis presents challenges, since energetic requirements may change across different cellular and environmental conditions. We developed a systems biology approach to estimate the cost of amino acid synthesis based on genome-scale metabolic models and investigated the effects of the cost of amino acid synthesis on Saccharomyces cerevisiae gene expression and protein evolution. First, we used our two new and six previously reported measures of amino acid cost in conjunction with codon usage bias, tRNA gene number and atomic composition to identify which of these factors best predict transcript and protein levels. Second, we compared amino acid cost with rates of amino acid substitution across four species in the genus Saccharomyces. Regardless of which cost measure is used, amino acid biosynthetic cost is weakly associated with transcript and protein levels. In contrast, we find that biosynthetic cost and amino acid substitution rates show a negative correlation, but for only a subset of cost measures. In the economy of the yeast cell, we find that the cost of amino acid synthesis plays a limited role in shaping transcript and protein expression levels compared to that of translational optimisation. Biosynthetic cost does, however, appear to affect rates of amino acid evolution in Saccharomyces, suggesting that expensive amino acids may only be used when they have specific structural or functional roles in protein sequences. However, as there appears to be no single currency to compute the cost of amino acid synthesis across all cellular and environmental

  5. All-order renormalization of propagator matrix for fermionic system with flavor mixing

    Energy Technology Data Exchange (ETDEWEB)

    Kniehl, Bernd A. [California Univ., Santa Barbara, CA (United States). Kavli Inst. for Theoretical Physics

    2013-08-15

    We consider a mixed system of Dirac fermions in a general parity-nonconserving theory and renormalize the propagator matrix to all orders in the pole scheme, in which the squares of the renormalized masses are identified with the complex pole positions and the wave-function renormalization (WFR) matrices are adjusted in compliance with the Lehmann-Symanzik-Zimmermann reduction formalism. We present closed analytic all-order expressions for the renormalization constants in terms of the scalar, pseudoscalar, vector, and pseudovector parts of the unrenormalized self-energy matrix, which is computable from the one-particle-irreducible Feynman diagrams of the flavor transitions. We identify residual degrees of freedom in the WFR matrices and propose an additional renormalization condition to exhaust them. We then explain how our results may be generalized to the case of unstable fermions, in which we encounter the phenomenon of WFR bifurcation. In the special case of a solitary unstable fermion, the all-order-renormalized propagator is presented in a particularly compact form.

  6. Radiation resistance of GFRP and CFRP using bisphenol A system epoxy as matrix

    International Nuclear Information System (INIS)

    The use of fiber-reinforced plastics as structural materials is increasing, but they are apt to be affected by the environment of their use unlike metals. When FRPs are used as the material requiring endurance, the resin composing the FRPs deteriorates due to radiation, and it causes the lowering of the characteristics of the FRPs. Accordingly, it is very important to evaluate the radiation resistance of FRPs and to understand the mechanism of deterioration. In this study, the deterioration due to electron beam irradiation and its mechanism of glass fiber reinforced plastics (GFRP) and carbon fiber reinforced plastics (CFRP) using bisphenol A system epoxy as the matrix were evaluated by bending strength test, rate of boiling water absorption test and scanning acoustic microscope observation, and the radiation resistance based on the difference of fiber materials was examined. The samples, the irradiation using a Dynamitron electron accelerator, the above mentioned testing methods and the results are reported. The nondestructive information on interface separation, microvoids and cracks in the matrix was given by acoustic microscope images. (K.I.)

  7. An Ultrasonic Imaging System Using a Matrix-Type Transducer Array

    Science.gov (United States)

    Noguchi, Michitoshi; Mizutani, Koichi; Nagai, Keinosuke; Yamashita, Yoshinari

    1999-05-01

    We propose a method for imaging an object's surface using a matrix-type transducer array. The matrix-type transducer array has a simple structure with some line-electrode fingers on both sides of a piezoelectric ceramic plate. By a combination of electrical-mechanical scanning, we image of an object's surface using data of distance between the transducer and the object. The ultrasonic probe used in the present system requires without beam forming and no signal processing for focusing. We measure two objects: one has a multilayered structure consisting of three differently sized aluminum plates, the biggest plate having an area of 150 mm × 80 mm and 0.8 1.5 mm thickness; and the other is a radio-wave-absorbent block 100.5 mm × 100.5 mm × 18.5 mm in size with 5 × 5 holes in a grid made of ferrite. The ultrasonic probe operates at a frequency of 3.5 MHz and the sensing distance between the transducer and the measured object is about 80 mm. At this distance, the diameter of the ultrasonic beam launched from the transducer is about 13 mm. We obtained a height resolution of ±0.2 mm and a spatial resolution of about 3.0 mm.

  8. Nucleic acid detection system and method for detecting influenza

    Energy Technology Data Exchange (ETDEWEB)

    Cai, Hong; Song, Jian

    2015-03-17

    The invention provides a rapid, sensitive and specific nucleic acid detection system which utilizes isothermal nucleic acid amplification in combination with a lateral flow chromatographic device, or DNA dipstick, for DNA-hybridization detection. The system of the invention requires no complex instrumentation or electronic hardware, and provides a low cost nucleic acid detection system suitable for highly sensitive pathogen detection. Hybridization to single-stranded DNA amplification products using the system of the invention provides a sensitive and specific means by which assays can be multiplexed for the detection of multiple target sequences.

  9. Effect of the matrix system in the delivery and in vitro bioactivity of microencapsulated Oregano essential oil

    OpenAIRE

    Costa, Sara Beirão da; Duarte, Cláudia; Bourbon, A. I.; A. C. Pinheiro; Serra, Ana Teresa; Martins, Margarida Moldão; Januário, Maria Isabel Nunes; Vicente, A.A.; Delgadillo, Ivonne; Duarte, Catarina; Costa, Maria Luísa Beirão da

    2012-01-01

    The effect of encapsulating matrix on retention, protection and delivery of Oregano essential oil (EO) was studied. EO was encapsulated in rice starch porous spheres, inulin and gelatine/sucrose capsules by spray drying. Gelatine/sucrose matrix was also dried by freeze drying. Experimental designs were applied to test the effect of bonding agents and solids content for rice starch and drying temperature and solids content for inulin and gelatine/sucrose systems. The ratio of gelatine/sucro...

  10. Determination of the fatty acid composition of saponified vegetable oils using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.

    Science.gov (United States)

    Ayorinde, F O; Garvin, K; Saeed, K

    2000-01-01

    A method using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) for the determination of the fatty acid composition of vegetable oils is described and illustrated with the analysis of palm kernel oil, palm oil, olive oil, canola oil, soybean oil, vernonia oil, and castor oil. Solutions of the saponified oils, mixed with the matrix, meso-tetrakis(pentafluorophenyl)porphyrin, provided reproducible MALDI-TOF spectra in which the ions were dominated by sodiated sodium carboxylates [RCOONa + Na]+. Thus, palm kernel oil was found to contain capric acid, lauric acid, myristic acid, palmitic acid, oleic acid, and stearic acid. Palm oil had a fatty acid profile including palmitic, linoleic, oleic, and stearic. The relative percentages of the fatty acids in olive oil were palmitoleic (1.2 +/- 0.5), palmitic (10.9 +/- 0.8), linoleic (0.6 +/- 0.1), linoleic (16.5 +/- 0.8), and oleic (70.5 +/- 1.2). For soybean oil, the relative percentages were: palmitoleic (0.4 +/- 0.4), palmitic (6.0 +/- 1.3), linolenic (14.5 +/- 1.8), linoleic (50.1 +/- 4.0), oleic (26.1 +/- 1.2), and stearic (2.2 +/- 0.7). This method was also applied to the analysis of two commercial soap formulations. The first soap gave a fatty acid profile that included: lauric (19.4% +/- 0.8), myristic (9.6% +/- 0.5), palmitoleic (1.9% +/- 0.3), palmitic (16.3% +/- 0.9), linoleic (5.6% +/- 0.4), oleic (37.1% +/- 0.8), and stearic (10.1% +/- 0.7) and that of the second soap was: lauric (9.3% +/- 0.3), myristic (3.8% +/- 0.5), palmitoleic (3.1% +/- 0.8), palmitic (19.4% +/- 0.8), linoleic (4.9% +/- 0.7), oleic (49.5% +/- 1.1), and stearic (10.0% +/- 0.9). The MALDI-TOFMS method described in this communication is simpler and less time-consuming than the established transesterification method that is coupled with analysis by gas chromatography/mass spectrometry (GC/MS). The new method could be used routinely to determine the qualitative fatty acid composition of vegetable oils

  11. Corrosion Inhibition by – Phthalic Acid - Zn2+ System

    Directory of Open Access Journals (Sweden)

    R. Mohan

    2014-05-01

    Full Text Available The inhibition effect of Phthalic acid(PA – Zn2+ system controls the corrosion of carbon steel has been studied by weight – loss method. The weight – loss study reveals that the formulation consisting of 60 ppm of Zn2+, 50 ppm of phthalic acid has 82 % inhibition efficiency. Synergistic effect exists between phthalic acid- Zn2+ system. The influence of N-cetyl- N, N, N-trimethylammonium bromide(CTAB on the PA- Zn2+ system control the microbial corrosion. The value of the separation factor, RL indicated the phthalic acid- Zn2+ system was favorable adsorption. The Adsorption equilibrium exhibited better fit to Langmuir isotherm than Freundlich isotherm. The protective film consists of Fe2+ - Phthalic acid and Zn(OH2 by FTIR spectroscopy.

  12. Phenolic Acids in Plant-Soil-Microbe System: A Review

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Phenolic acids are very common compounds in pedosphere. The objective of this review was to summarize the current knowledge of the behaviors of phenolic acids in plant-soil-microbe system. When phenolic acids originated from leaching, decomposition and exudation of living and dead plant tissues enter soils, they can react physicochemically with soil particle surfaces and/or incorporate into humic matter. Phenolic acids desorbed from soil particle surfaces and remained in solution phase can be utilized by microbe as carbon sources and absorbed by plants. The degradation products of phenolic acids by microbe include some organic and/or inorganic compounds such as new phenolic acids. In addition, phenolic acids in soils can stimulate population and activity of microbe. Phenolic acids can inhibit plants growth by affecting ion leakage, phytohormone activity, membrane permeability, hydraulic conductivity, net nutrient uptake, and enzyme activity. Behaviors of phenolic acids in soils are influenced by other organic compounds (phenolic acids, methionine, glucose, etc.) and/or inorganic ions. The role of phenolic acids as allelopathic agents should not be neglected only based on their low specific concentrations in natural soils, because numbers and interactions of phenolic acids will increase their allelopathic activities.

  13. Comparative researches on two direct transmethylation without prior extraction methods for fatty acids analysis in vegetal matrix with low fat content

    Directory of Open Access Journals (Sweden)

    Harmanescu Monica

    2012-01-01

    Full Text Available Abstract Background The aim of our work was to compare two methods, both based on direct transmethylation with different reagents, BF3/MeOH (boron trifluoride in methanol or HCl/MeOH (hydrochloride acid in methanol, in acid catalysis, without prior extraction, to find the fast, non-expensive but enough precise method for 9 principal fatty acids (lauric, myristic, palmitic, stearic, oleic, linoleic, linolenic, arahidic and behenic acids analysis in vegetal matrix with low fat content (forage from grassland, for nutrition and agrochemical studies. Results Comparatively, between the average values obtained for all analysed fatty acids by the two methods based on direct transmethylation without prior extraction no significantly difference was identified (p > 0.05. The results of fatty acids for the same forage sample were more closely to their average value, being more homogenous for BF3/MeOH than HCl/MeOH, because of the better accuracy and repeatability of this method. Method that uses BF3/MeOH reagent produces small amounts of interfering compounds than the method using HCl/MeOH reagent, results reflected by the better statistical parameters. Conclusion The fast and non-expensive BF3/methanol method was applied with good accuracy and sensitivity for the determination of free or combined fatty acids (saturated and unsaturated in forage matrix with low fat content from grassland. Also, the final extract obtained by this method, poorer in interfering compounds, is safer to protect the injector and column from contamination with heavy or non-volatile compounds formed by transmethylation reactions.

  14. Abscisic acid ameliorates the systemic sclerosis fibroblast phenotype in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Bruzzone, Santina, E-mail: santina.bruzzone@unige.it [Department of Experimental Medicine, Section of Biochemistry, University of Genova, Viale Benedetto XV 1, 16132 Genova (Italy); Centre of Excellence for Biomedical Research, University of Genova, Viale Benedetto XV 9, 16132 Genova (Italy); Advanced Biotechnology Center, Largo Rosanna Benzi 10, 16132 Genova (Italy); Battaglia, Florinda [Centre of Excellence for Biomedical Research, University of Genova, Viale Benedetto XV 9, 16132 Genova (Italy); Mannino, Elena [Department of Experimental Medicine, Section of Biochemistry, University of Genova, Viale Benedetto XV 1, 16132 Genova (Italy); Parodi, Alessia [Centre of Excellence for Biomedical Research, University of Genova, Viale Benedetto XV 9, 16132 Genova (Italy); Fruscione, Floriana [Department of Experimental Medicine, Section of Biochemistry, University of Genova, Viale Benedetto XV 1, 16132 Genova (Italy); Advanced Biotechnology Center, Largo Rosanna Benzi 10, 16132 Genova (Italy); Basile, Giovanna [Department of Experimental Medicine, Section of Biochemistry, University of Genova, Viale Benedetto XV 1, 16132 Genova (Italy); Salis, Annalisa; Sturla, Laura [Department of Experimental Medicine, Section of Biochemistry, University of Genova, Viale Benedetto XV 1, 16132 Genova (Italy); Centre of Excellence for Biomedical Research, University of Genova, Viale Benedetto XV 9, 16132 Genova (Italy); Negrini, Simone; Kalli, Francesca; Stringara, Silvia [Centre of Excellence for Biomedical Research, University of Genova, Viale Benedetto XV 9, 16132 Genova (Italy); Filaci, Gilberto [Centre of Excellence for Biomedical Research, University of Genova, Viale Benedetto XV 9, 16132 Genova (Italy); Department of Internal Medicine, Viale Benedetto XV 6, 16132 Genova (Italy); and others

    2012-05-25

    Highlights: Black-Right-Pointing-Pointer ABA is an endogenous hormone in humans, regulating different cell responses. Black-Right-Pointing-Pointer ABA reverts some of the functions altered in SSc fibroblasts to a normal phenotype. Black-Right-Pointing-Pointer UV-B irradiation increases ABA content in SSc cultures. Black-Right-Pointing-Pointer SSc fibroblasts could benefit from exposure to ABA and/or to UV-B. -- Abstract: The phytohormone abscisic acid (ABA) has been recently identified as an endogenous hormone in humans, regulating different cell functions, including inflammatory processes, insulin release and glucose uptake. Systemic sclerosis (SSc) is a chronic inflammatory disease resulting in fibrosis of skin and internal organs. In this study, we investigated the effect of exogenous ABA on fibroblasts obtained from healthy subjects and from SSc patients. Migration of control fibroblasts induced by ABA was comparable to that induced by transforming growth factor-{beta} (TGF-{beta}). Conversely, migration toward ABA, but not toward TGF-{beta}, was impaired in SSc fibroblasts. In addition, ABA increased cell proliferation in fibroblasts from SSc patients, but not from healthy subjects. Most importantly, presence of ABA significantly decreased collagen deposition by SSc fibroblasts, at the same time increasing matrix metalloproteinase-1 activity and decreasing the expression level of tissue inhibitor of metalloproteinase (TIMP-1). Thus, exogenously added ABA appeared to revert some of the functions altered in SSc fibroblasts to a normal phenotype. Interestingly, ABA levels in plasma from SSc patients were found to be significantly lower than in healthy subjects. UV-B irradiation induced an almost 3-fold increase in ABA content in SSc cultures. Altogether, these results suggest that the fibrotic skin lesions in SSc patients could benefit from exposure to high(er) ABA levels.

  15. Abscisic acid ameliorates the systemic sclerosis fibroblast phenotype in vitro

    International Nuclear Information System (INIS)

    Highlights: ► ABA is an endogenous hormone in humans, regulating different cell responses. ► ABA reverts some of the functions altered in SSc fibroblasts to a normal phenotype. ► UV-B irradiation increases ABA content in SSc cultures. ► SSc fibroblasts could benefit from exposure to ABA and/or to UV-B. -- Abstract: The phytohormone abscisic acid (ABA) has been recently identified as an endogenous hormone in humans, regulating different cell functions, including inflammatory processes, insulin release and glucose uptake. Systemic sclerosis (SSc) is a chronic inflammatory disease resulting in fibrosis of skin and internal organs. In this study, we investigated the effect of exogenous ABA on fibroblasts obtained from healthy subjects and from SSc patients. Migration of control fibroblasts induced by ABA was comparable to that induced by transforming growth factor-β (TGF-β). Conversely, migration toward ABA, but not toward TGF-β, was impaired in SSc fibroblasts. In addition, ABA increased cell proliferation in fibroblasts from SSc patients, but not from healthy subjects. Most importantly, presence of ABA significantly decreased collagen deposition by SSc fibroblasts, at the same time increasing matrix metalloproteinase-1 activity and decreasing the expression level of tissue inhibitor of metalloproteinase (TIMP-1). Thus, exogenously added ABA appeared to revert some of the functions altered in SSc fibroblasts to a normal phenotype. Interestingly, ABA levels in plasma from SSc patients were found to be significantly lower than in healthy subjects. UV-B irradiation induced an almost 3-fold increase in ABA content in SSc cultures. Altogether, these results suggest that the fibrotic skin lesions in SSc patients could benefit from exposure to high(er) ABA levels.

  16. A Moebius-Strip Representation of the Matrix-Product Periodic System of Diatomic Molecules

    Science.gov (United States)

    Hefferlin, Ray

    2007-04-01

    Periodic systems of diatomic and triatomic molecules are well tested and documented [1]. The 3D form of the diatomic system consists of blocks, each having all molecules with two fixed-row atoms, on which the molecules are addressed by their atomic group numbers. The blocks can be replaced by tori [2], but in either case many redundancies exist (e.g., CO and OC). The tori [3] may be replaced by Moebius strips [4] which remove the redundancies. This representation of the periodic system will be presented. [1] Hefferlin, R., ``The Periodic Systems of Molecules, Presuppositions, Problems, and Prospects,'' Baird, D., Scerri, E., and McIntyre, L., Editors, Philosophy of Chemistry, Boston Studies in the Philosophy of Science, Springer, Dodrecht, the Netherlands, 2006. [2] Hefferlin, R,. ``Matrix-Product Periodic Systems of Molecules,'' J. Chem. Inf. Comput. Sci, 34, 314-317 (1994). [3] Hall, D. E, ``Quantitative Evaluation of Musical Scale Tunings,'' AJP, 42, 543-552 (1974). [4] Blau, S. K., ``Good Music unfolds in Small Steps,'' Physics Today, October 2006, pp. 19-21.

  17. Bidirectional output stage matrix converter applied to a distributed generation system

    Science.gov (United States)

    Ortega, Manuel; Jurado, Francisco; Roa, Juan P.

    2012-08-01

    In this article a new bidirectional output stage ultra-sparse matrix converter (BOSUMC) is presented. This converter is designed for connecting a hybrid electrical system to a distributed generation network. The proposed converter comprises an input stage and an output stage with six bidirectional switches in such a way that both the input and output stages are linked with a DC link, which can be coupled to an electrolyser and a fuel cell. The converter allows the current to flow in both ways in its output stage, and if there is an excess of energy in the network, it can be transformed into electric direct current and later into hydrogen for its exploitation. For verifying the control algorithm of the BOSUMC, a laboratory prototype has been prepared using among other elements a Spectrum Digital eZdsp™ TMS320F2812 card.

  18. Extraction of food consumption systems by nonnegative matrix factorization (NMF) for the assessment of food choices.

    Science.gov (United States)

    Zetlaoui, Mélanie; Feinberg, Max; Verger, Philippe; Clémençon, Stephan

    2011-12-01

    In Western countries where food supply is satisfactory, consumers organize their diets around a large combination of foods. It is the purpose of this article to examine how recent nonnegative matrix factorization (NMF) techniques can be applied to food consumption data to understand these combinations. Such data are nonnegative by nature and of high dimension. The NMF model provides a representation of consumption data through latent vectors with nonnegative coefficients, that we call consumption systems (CS), in a small number. As the NMF approach may encourage sparsity of the data representation produced, the resulting CS are easily interpretable. Beyond the illustration of its properties we provide through a simple simulation result, the NMF method is applied to data issued from a French consumption survey. The numerical results thus obtained are displayed and thoroughly discussed. A clustering based on the k-means method is also achieved in the resulting latent consumption space, to recover food consumption patterns easily usable for nutritionists. PMID:21418050

  19. Optimum Co-Design for Spectrum Sharing between Matrix Completion Based MIMO Radars and a MIMO Communication System

    Science.gov (United States)

    Li, Bo; Petropulu, Athina P.; Trappe, Wade

    2016-09-01

    Recently proposed multiple input multiple output radars based on matrix completion (MIMO-MC) employ sparse sampling to reduce the amount of data that need to be forwarded to the radar fusion center, and as such enable savings in communication power and bandwidth. This paper proposes designs that optimize the sharing of spectrum between a MIMO-MC radar and a communication system, so that the latter interferes minimally with the former. First, the communication system transmit covariance matrix is designed to minimize the effective interference power (EIP) to the radar receiver, while maintaining certain average capacity and transmit power for the communication system. Two approaches are proposed, namely a noncooperative and a cooperative approach, with the latter being applicable when the radar sampling scheme is known at the communication system. Second, a joint design of the communication transmit covariance matrix and the MIMO-MC radar sampling scheme is proposed, which achieves even further EIP reduction.

  20. Unified parametric approaches for high-order integral observer design for matrix second-order linear systems

    Institute of Scientific and Technical Information of China (English)

    Guangren DUAN; Yunli WU

    2006-01-01

    A type of high-order integral observers for matrix second-order linear systems is proposed on the basis of generalized eigenstructure assignment via unified parametric approaches. Through establishing two general parametric solutions to this type of generalized matrix second-order Sylvester matrix equations, two unified complete parametric methods for the proposed observer design problem are presented. Both methods give simple complete parametric expressions for the observer gain matrices. The first one mainly depends on a series of singular value decompositions, and is thus numerically simple and reliable; the second one utilizes the right factorization of the system, and allows eigenvalues of the error system to be set undetermined and sought via certain optimization procedures. A spring-mass-dashpot system is utilized to illustrate the design procedure and show the effect of the proposed approach.

  1. PET image reconstruction with system matrix based on point spread function derived from single photon incidence response

    CERN Document Server

    Xin, Fan; Ming-Kai, Yun; Xiao-Li, Sun; Xue-Xiang, Cao; Shuang-Quanm, Liu; Pei, Chai; Dao-Wu, Li; Long, Wei

    2014-01-01

    In positron emission tomography (PET) imaging, statistical iterative reconstruction (IR) techniques appear particularly promising since they can provide accurate physical model and geometric system description. The reconstructed image quality mainly depends on the system matrix model which describes the relationship between image space and projection space for the IR method. The system matrix can contain some physics factors of detection such as geometrical component and blurring component. Point spread function (PSF) is generally used to describe the blurring component. This paper proposes an IR method based on the PSF system matrix, which is derived from the single photon incidence response function. More specifically, the gamma photon incidence on a crystal array is simulated by the Monte Carlo (MC) simulation, and then the single photon incidence response functions are obtained. Subsequently, using the single photon incidence response functions, the coincidence blurring factor is acquired according to the...

  2. Thermal conductivity and acid dissolution behavior of MgO-ZrO 2 ceramics for use in LWR inert matrix fuel

    Science.gov (United States)

    Medvedev, P. G.; Lambregts, M. J.; Meyer, M. K.

    2006-02-01

    Dual-phase MgO-ZrO 2 ceramics are proposed for use in inert matrix fuel for disposition of plutonium and minor actinides in existing light water reactors. The concept for use of this composite material was developed with the intent to capitalize on the known advantages of the composite's constituents: high thermal conductivity of MgO, and stability of ZrO 2 in LWR coolant. The study presented in this paper addressed the thermal conductivity and nitric acid solubility of MgO-ZrO 2 ceramics. Thermal analysis, based on experimental and analytical techniques, established that the product of all investigated compositions has the thermal conductivity superior to that of UO 2. Nitric acid dissolution experiments showed that only the free MgO phase dissolves in the nitric acid, leaving behind a porous pellet consisting of a ZrO 2-based solid solution.

  3. Matrix light and pixel light: optical system architecture and requirements to the light source

    Science.gov (United States)

    Spinger, Benno; Timinger, Andreas L.

    2015-09-01

    Modern Automotive headlamps enable improved functionality for more driving comfort and safety. Matrix or Pixel light headlamps are not restricted to either pure low beam functionality or pure high beam. Light in direction of oncoming traffic is selectively switched of, potential hazard can be marked via an isolated beam and the illumination on the road can even follow a bend. The optical architectures that enable these advanced functionalities are diverse. Electromechanical shutters and lens units moved by electric motors were the first ways to realize these systems. Switching multiple LED light sources is a more elegant and mechanically robust solution. While many basic functionalities can already be realized with a limited number of LEDs, an increasing number of pixels will lead to more driving comfort and better visibility. The required optical system needs not only to generate a desired beam distribution with a high angular dynamic, but also needs to guarantee minimal stray light and cross talk between the different pixels. The direct projection of the LED array via a lens is a simple but not very efficient optical system. We discuss different optical elements for pre-collimating the light with minimal cross talk and improved contrast between neighboring pixels. Depending on the selected optical system, we derive the basic light source requirements: luminance, surface area, contrast, flux and color homogeneity.

  4. Closed-form solutions for linear regulator design of mechanical systems including optimal weighting matrix selection

    Science.gov (United States)

    Hanks, Brantley R.; Skelton, Robert E.

    1991-01-01

    Vibration in modern structural and mechanical systems can be reduced in amplitude by increasing stiffness, redistributing stiffness and mass, and/or adding damping if design techniques are available to do so. Linear Quadratic Regulator (LQR) theory in modern multivariable control design, attacks the general dissipative elastic system design problem in a global formulation. The optimal design, however, allows electronic connections and phase relations which are not physically practical or possible in passive structural-mechanical devices. The restriction of LQR solutions (to the Algebraic Riccati Equation) to design spaces which can be implemented as passive structural members and/or dampers is addressed. A general closed-form solution to the optimal free-decay control problem is presented which is tailored for structural-mechanical system. The solution includes, as subsets, special cases such as the Rayleigh Dissipation Function and total energy. Weighting matrix selection is a constrained choice among several parameters to obtain desired physical relationships. The closed-form solution is also applicable to active control design for systems where perfect, collocated actuator-sensor pairs exist.

  5. Modeling multi-component transport and enhanced anaerobic dechlorination processes in a single fracture-clay matrix system

    DEFF Research Database (Denmark)

    Chambon, Julie Claire Claudia; Broholm, Mette Martina; Binning, Philip John;

    2010-01-01

    of a contaminant in a single fracture-clay matrix system coupled with a reactive model for anaerobic dechlorination. The model takes into account microbially driven anaerobic dechlorination, where sequential Monod kinetics with competitive inhibition is used to model the reaction rates, and degradation...... is localized to account for potential pore size limitations on microbial entry to the clay matrix. The model is used to assess the distribution of TCE and its daughter products in the clay matrix and the concentration of the different compounds at the outlet of the fracture. The time frame for complete cleanup...... to the physical processes, mainly diffusion in the matrix, than to the biogeochemical processes, when dechlorination is assumed to take place in a limited reaction zone only. The inclusion of sequential dechlorination in clay fracture transport models is crucial, as the contaminant flux to the aquifer...

  6. Phase diagram of the ternary system lauric acid-capric acid-naphthalene

    Energy Technology Data Exchange (ETDEWEB)

    Longfei, Jin; Fengping, Xiao [College of Chemistry, Central China Normal University, Wuhan 430079 (China)

    2004-12-15

    The mixture of lauric acid and capric acid is a potential latent heat storage material. However, its eutectic melting temperature is quite high for low-temperature thermal energy storage. Addition of naphthalene is proposed. The ternary system lauric acid-capric acid-naphthalene has been investigated by differential scanning calorimetry (DSC), visual polythermal and chromatography of gases. The phase diagram is of an incongruent eutectic type. The eutectic mixture contains 18.4mol% lauric acid, 63.1mol% capric acid and 18.5mol% naphthalene and melts at 13.3{sup o}C. The peritectic mixture contains 32.4mol% lauric acid, 48.2mol% capric acid and 19.4mol% naphthalene and peritectic temperature of 16.2{sup o}C. The incongruent compound was analysed to be CH{sub 3}(CH{sub 2}){sub 10}COOH.CH{sub 3}(CH{sub 2}){sub 8}COOH. The melting temperature of the lauric acid-capric acid-naphthalene eutectic mixture makes it suitable for cooling applications.

  7. On the Centro-symmetric Solution of a System of Matrix Equations over a Regular Ring with Identity

    Institute of Scientific and Technical Information of China (English)

    Qingwen Wang; Haixia Chang; Chunyan Lin

    2007-01-01

    In this paper, we find the centro-symmetric solution of a system of matrix equations over an arbitrary regular ring R with identity. We first derive some necessary and sufficient conditions for the existence and an explicit expression of the general solution of the system of matrix equations A1X1 = C1, A2X1 = C2, A3X2 = C3, A4X2 = C4 and A5X1B5 + A6X2B6= C5 over R. By using the above results, we establish two criteria for the existence and the representation of the general centro-symmetric solution of the system of matrix equations AaX = Ca, AbX = Cb and AcXBc = Cc over the ring R.

  8. Wavefront response matrix for closed-loop adaptive optics system based on non-modulation pyramid wavefront sensor

    Science.gov (United States)

    Wang, Jianxin; Bai, Fuzhong; Ning, Yu; Li, Fei; Jiang, Wenhan

    2012-06-01

    Pyramid wavefront sensor (PWFS) is a kind of wavefront sensor with high spatial resolution and high energy utilization. In this paper an adaptive optics system with PWFS as wavefront sensor and liquid-crystal spatial light modulator (LC-SLM) as wavefront corrector is built in the laboratory. The wavefront response matrix is a key element in the close-loop operation. It can be obtained by measuring the real response to given aberrations, which is easily contaminated by noise and influenced by the inherent aberration in the optical system. A kind of analytic solution of response matrix is proposed, with which numerical simulation and experiment are also implemented to verify the performance of closed-loop correction of static aberration based on linear reconstruction theory. Results show that this AO system with the proposed matrix can work steadily in closed-loop operation.

  9. On the Free Vibration Modeling of Spindle Systems: A Calibrated Dynamic Stiffness Matrix

    Directory of Open Access Journals (Sweden)

    Omar Gaber

    2014-01-01

    Full Text Available The effect of bearings on the vibrational behavior of machine tool spindles is investigated. This is done through the development of a calibrated dynamic stiffness matrix (CDSM method, where the bearings flexibility is represented by massless linear spring elements with tuneable stiffness. A dedicated MATLAB code is written to develop and to assemble the element stiffness matrices for the system’s multiple components and to apply the boundary conditions. The developed method is applied to an illustrative example of spindle system. When the spindle bearings are modeled as simply supported boundary conditions, the DSM model results in a fundamental frequency much higher than the system’s nominal value. The simply supported boundary conditions are then replaced by linear spring elements, and the spring constants are adjusted such that the resulting calibrated CDSM model leads to the nominal fundamental frequency of the spindle system. The spindle frequency results are also validated against the experimental data. The proposed method can be effectively applied to predict the vibration characteristics of spindle systems supported by bearings.

  10. Development of a robust once-a-day glipizide matrix system.

    Science.gov (United States)

    Jamzad, Shahla; Fassihi, Reza

    2007-06-01

    The robustness of a new hydroxypropylmethylcellulose (HPMC) based modified release glipizide (10 mg) formulation was studied. The tablet formulations were prepared by dry blending the ingredients and direct compression, incorporating a range of release modifying agents up to +/-20% w/w relative to an optimized formulation. The dissolution was assessed in 900 mL pH 6.8 buffer at 75 rev min(-1) paddle speed. Calculated difference and similarity factors (f(1) and f(2)) and results of analysis of variance suggest that the overall release profiles were similar. Compositional changes up to +/-20% w/w and a reduction of drug dose to half did not change the general release pattern of this low dose/pH-dependent drug in a significant way. It is concluded that the drug release from the developed matrix systems is highly dependent on the kinetics of hydration and erosion, and that the proposed compositional changes within +/-20% w/w did not alter this relationship. The particulate systems used were characterized by determining the Carr index, Hausner ratio and the rheological properties using a texture analyser. Results indicate that the release is reproducible and the system has potential for successful scale-up operation, while complying with recommended Food and Drug Administration guidelines "Scale Up and Post Approval Changes". PMID:17637169

  11. Determination of Iron in Layered Crystal Sodium Disilicate and Sodium Silicate by Flame Atomic Absorption Spectrometry with Boric Acid as a Matrix Modifier

    Institute of Scientific and Technical Information of China (English)

    Zhi Hua WANG; Min CAI; Shu Jun WANG

    2006-01-01

    The effects of matrix silicate and experimental conditions on the determination of iron in flame atomic absorption spectrometry (FAAS) were investigated. It was found that boric acid as a matrix modifier obviously eliminated silicate interference. Under the optimum operating conditions, the determination results of iron in layered crystal sodium disilicate and sodium silicate samples by FAAS were satisfactory. The linear range of calibration curve is 0-10.5 μg.mL-1, the relative standard deviation of method is 1.2%-2.2%, the recovery of added iron is 96.0%-101%, the of iron of the standard curve method, standard addition calibration and colorimetry method was the same, but the first has the merits of rapid sample preparation, reduced contamination risks and fast analysis.

  12. Amino Acid Synthesis in a Supercritical Carbon Dioxide - Water System

    Directory of Open Access Journals (Sweden)

    Akiyoshi Hoshino

    2009-06-01

    Full Text Available Mars is a CO2-abundant planet, whereas early Earth is thought to be also CO2-abundant. In addition, water was also discovered on Mars in 2008. From the facts and theory, we assumed that soda fountains were present on both planets, and this affected amino acid synthesis. Here, using a supercritical CO2/liquid H2O (10:1 system which mimicked crust soda fountains, we demonstrate production of amino acids from hydroxylamine (nitrogen source and keto acids (oxylic acid sources. In this research, several amino acids were detected with an amino acid analyzer. Moreover, alanine polymers were detected with LC-MS. Our research lights up a new pathway in the study of life’s origin.

  13. Radiolytic degradation of sorbic acid in isolated systems

    International Nuclear Information System (INIS)

    Effect of Co(60) gamma-irradiation on stability of sorbic acid (SA) in solutions, dough and chapaties has been investigated. SA was highly susceptible to radiolytic degradation in aqueous systems. Rate of degradation decreased with rise in pH. Sugars, hydrocolloids except pectin, citric acid, lactic acid, malic acid, arginine and threonine, catalyzed degradation while oxalic acid, maleic acid, Cu2+, nitrite, nitrate and phthalate had protective effects. SA was more stable in alcohols and vegetable oils than in aqueous solutions. In wheat flour radiolytic degradation of SA was less at lower moisture. Relatively SA was more stable in chapaties than in dough. Gelatinization and addition of oil in dough reduced degradation of SA

  14. 300 Area waste acid treatment system closure plan. Revision 1

    International Nuclear Information System (INIS)

    This section provides a description of the Hanford Site, identifies the proposed method of 300 Area Waste Acid Treatment System (WATS) closure, and briefly summarizes the contents of each chapter of this plan

  15. Ammonia-treated N-(1-naphthyl) ethylenediamine dihydrochloride as a novel matrix for rapid quantitative and qualitative determination of serum free fatty acids by matrix-assisted laser desorption/ionization-Fourier transform ion cyclotron resonance mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yaping [Department of Biophysics and Structural Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and School of Basic Medicine, Peking Union Medical College, 5 Dongdan San Tiao, Beijing 100005 (China); Wang, Yanmin [Department of Clinical Laboratory, Heze Municipal Hospital, Shandong (China); Guo, Shuai; Guo, Yumei; Liu, Hui [Department of Biophysics and Structural Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and School of Basic Medicine, Peking Union Medical College, 5 Dongdan San Tiao, Beijing 100005 (China); Li, Zhili, E-mail: lizhili@ibms.pumc.edu.cn [Department of Biophysics and Structural Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and School of Basic Medicine, Peking Union Medical College, 5 Dongdan San Tiao, Beijing 100005 (China)

    2013-09-10

    Graphical abstract: -- Highlights: •A novel MALDI matrix for the detection of serum free fatty acids is ammonia-treated N-(1-naphthyl) ethylenediamine dihydrochloride. •Multiple point internal standard calibration curves were constructed for nine FFAs, respectively, with excellent correlation coefficients between 0.991 and 0.999. •The MALDI-MS approach was used to rapidly differentiate the patients with and without hyperglycemia and healthy controls. -- Abstract: The blood free fatty acids (FFAs), which provide energy to the cell and act as substrates in the synthesis of fats, lipoproteins, liposaccharides, and eicosanoids, involve in a number of important physiological processes. In the present study, matrix-assisted laser desorption/ionization-Fourier transform ion cyclotron resonance mass spectrometry (MALDI-FTICR MS) with ammonia-treated N-(1-naphthyl) ethylenediamine dihydrochloride (ATNEDC) as a novel MALDI matrix in a negative ion mode was employed to directly quantify serum FFAs. Multiple point internal standard calibration curves between the concentration ratios of individual fatty acids to internal standard (IS, C{sub 17:0}) versus their corresponding intensity ratios were constructed for C{sub 14:0}, C{sub 16:1}, C{sub 16:0}, C{sub 18:0}, C{sub 18:1}, C{sub 18:2}, C{sub 18:3}, C{sub 20:4}, and C{sub 22:6}, respectively, in their mixture, with correlation coefficients between 0.991 and 0.999 and limits of detection (LODs) between 0.2 and 5.4 μM, along with the linear dynamic range of more than two orders of magnitude. The results indicate that the multiple point internal standard calibration could reduce the impact of ion suppression and improve quantification accuracy in the MALDI mode. The quantitative results of nine FFAs from 339 serum samples, including 161 healthy controls, 118 patients with hyperglycemia and 60 patients without hyperglycemia show that FFAs levels in hyperglycemic patient sera are significantly higher than those in healthy

  16. Simultaneous determination of bromate, chlorite and haloacetic acids by two-dimensional matrix elimination ion chromatography with coupled conventional and capillary columns.

    Science.gov (United States)

    Teh, Hui Boon; Li, Sam Fong Yau

    2015-02-27

    A new, highly sensitive and reliable two-dimensional matrix elimination ion chromatography (IC) method was developed for simultaneous detection of bromate, chlorite and five haloacetic acids. This method combined the conventional IC in first dimension with capillary IC in the second dimension coupled with suppressed conductivity detection. The first dimension utilizes a high capacity column to partially resolve matrix from target analytes. By optimizing the cut window, the target analytes were selectively cut and trapped in a trap column through the use of a six-port valve, while the separated matrix were diverted to waste. The trapped target analytes were delivered on to the capillary column for further separation and detection. Temperature programming was used to improve selectivity in second dimension column to obtain complete resolution of the target analytes. Compared to the performance of one-dimensional IC, the two-dimensional approach resulted in a significant increase in sensitivity for all target analytes with limit of detection ranging from 0.30 to 0.64μg/L and provided more reliable analysis due to second column confirmation. Good linearity was obtained for all the target analytes with correlation coefficients >0.998. The proposed method was successfully applied to the determination of oxyhalides and haloacetic acids in various matrices with recoveries ranging from 90 to 116% and RSD less than 6.1%. The method allows direct injection of samples and the use of columns with different selectivity, thus significantly reduces the level of false positive results. The method is fully automated and simple, making it practical for routine monitoring of water quality. The satisfactory results also demonstrated that the two-dimensional matrix elimination method coupled with capillary IC is a promising approach for detection of trace substances in complex matrices.

  17. Influence of the composition of hydroxypropyl cellulose/maleic acid-alt-styrene copolymer blends on their properties as matrix for drug release

    Directory of Open Access Journals (Sweden)

    2009-05-01

    Full Text Available Poly(carboxylic acid-polysaccharide compositions have been found suitable for obtaining drug formulations with controlled release, most formulations being therapeutically efficacious, stable, and non-irritant. The influence of the characteristics of the aqueous solutions from which the polymer matrix is prepared (i.e. the total concentration of polymer in solutions and the mixing ratio between the partners, hydroxypropyl cellulose, HPC and maleic acid-alternating-styrene copolymer, MAc-alt-S on the kinetics of some drugs release in acidic environment (pH = 2 has been followed by ‘in vitro’ dissolution tests. It has been established that the kinetics of procaine hydrochloride release from HPC/MAc-alt-S matrix depends on its composition; the diffusion exponent, n is close to 0.5 for matrices where one of the components is in large excess and n~0.02 for middle composition range. The lower value of diffusion exponent for middle composition range could be caused by the so called ‘burst effect’, therefore the kinetic evaluation is difficult.

  18. On-Tissue Derivatization via Electrospray Deposition for Matrix-Assisted Laser Desorption/Ionization Mass Spectrometry Imaging of Endogenous Fatty Acids in Rat Brain Tissues.

    Science.gov (United States)

    Wu, Qian; Comi, Troy J; Li, Bin; Rubakhin, Stanislav S; Sweedler, Jonathan V

    2016-06-01

    Matrix-assisted laser desorption/ionization (MALDI) mass spectrometry imaging (MSI) is used for the multiplex detection and characterization of diverse analytes over a wide mass range directly from tissues. However, analyte coverage with MALDI MSI is typically limited to the more abundant compounds, which have m/z values that are distinct from MALDI matrix-related ions. On-tissue analyte derivatization addresses these issues by selectively tagging functional groups specific to a class of analytes, while simultaneously changing their molecular masses and improving their desorption and ionization efficiency. We evaluated electrospray deposition of liquid-phase derivatization agents as a means of on-tissue analyte derivatization using 2-picolylamine; we were able to detect a range of endogenous fatty acids with MALDI MSI. When compared with airbrush application, electrospray led to a 3-fold improvement in detection limits and decreased analyte delocalization. Six fatty acids were detected and visualized from rat cerebrum tissue using a MALDI MSI instrument operating in positive mode. MALDI MSI of the hippocampal area allowed targeted fatty acid analysis of the dentate gyrus granule cell layer and the CA1 pyramidal layer with a 20-μm pixel width, without degrading the localization of other lipids during liquid-phase analyte derivatization.

  19. On-Tissue Derivatization via Electrospray Deposition for Matrix-Assisted Laser Desorption/Ionization Mass Spectrometry Imaging of Endogenous Fatty Acids in Rat Brain Tissues.

    Science.gov (United States)

    Wu, Qian; Comi, Troy J; Li, Bin; Rubakhin, Stanislav S; Sweedler, Jonathan V

    2016-06-01

    Matrix-assisted laser desorption/ionization (MALDI) mass spectrometry imaging (MSI) is used for the multiplex detection and characterization of diverse analytes over a wide mass range directly from tissues. However, analyte coverage with MALDI MSI is typically limited to the more abundant compounds, which have m/z values that are distinct from MALDI matrix-related ions. On-tissue analyte derivatization addresses these issues by selectively tagging functional groups specific to a class of analytes, while simultaneously changing their molecular masses and improving their desorption and ionization efficiency. We evaluated electrospray deposition of liquid-phase derivatization agents as a means of on-tissue analyte derivatization using 2-picolylamine; we were able to detect a range of endogenous fatty acids with MALDI MSI. When compared with airbrush application, electrospray led to a 3-fold improvement in detection limits and decreased analyte delocalization. Six fatty acids were detected and visualized from rat cerebrum tissue using a MALDI MSI instrument operating in positive mode. MALDI MSI of the hippocampal area allowed targeted fatty acid analysis of the dentate gyrus granule cell layer and the CA1 pyramidal layer with a 20-μm pixel width, without degrading the localization of other lipids during liquid-phase analyte derivatization. PMID:27181709

  20. Acid-base homeostasis in the human system

    Science.gov (United States)

    White, R. J.

    1974-01-01

    Acid-base regulation is a cooperative phenomena in vivo with body fluids, extracellular and intracellular buffers, lungs, and kidneys all playing important roles. The present account is much too brief to be considered a review of present knowledge of these regulatory systems, and should be viewed, instead, as a guide to the elements necessary to construct a simple model of the mutual interactions of the acid-base regulatory systems of the body.

  1. Matrix Failure Modes and Effects Analysis as a Knowledge Base for a Real Time Automated Diagnosis Expert System

    Science.gov (United States)

    Herrin, Stephanie; Iverson, David; Spukovska, Lilly; Souza, Kenneth A. (Technical Monitor)

    1994-01-01

    Failure Modes and Effects Analysis contain a wealth of information that can be used to create the knowledge base required for building automated diagnostic Expert systems. A real time monitoring and diagnosis expert system based on an actual NASA project's matrix failure modes and effects analysis was developed. This Expert system Was developed at NASA Ames Research Center. This system was first used as a case study to monitor the Research Animal Holding Facility (RAHF), a Space Shuttle payload that is used to house and monitor animals in orbit so the effects of space flight and microgravity can be studied. The techniques developed for the RAHF monitoring and diagnosis Expert system are general enough to be used for monitoring and diagnosis of a variety of other systems that undergo a Matrix FMEA. This automated diagnosis system was successfully used on-line and validated on the Space Shuttle flight STS-58, mission SLS-2 in October 1993.

  2. Inert matrix fuel concept for the rapid incineration of minor actinides harmonious with a fast reactor cycle system

    International Nuclear Information System (INIS)

    We proposed a fast reactor cycle concept that incorporates inert matrix fuels as a high-performance device for rapid incineration of minor actinides and a harmonious system with the existing fast reactor cycle technologies. R and D of minor actinides containing advanced fuels for use in fast reactors is described in relation to inert matrix fuels with MgO, Mo and Si3N4. As related technologies, burn-up characteristics of a fast reactor core loaded with the inert matrix fuel with MgO and Mo were analyzed, mainly in terms of core criticality. Fabrication tests of inert matrix fuels with MgO, Mo and Si3N4 were done by a practical process that could be adapted to the presently-used commercial manufacturing technology. Preliminary investigations for the solubility of inert matrix fuels to the HNO3 were carried out for the evaluation of applicability to existing reprocessing technology. This paper describes a part of our efforts towards the establishment of a fast reactor cycle that incorporates the minor actinides containing inert matrix fuels. (author)

  3. The density matrix renormalization group for strongly correlated electron systems: A generic implementation

    Science.gov (United States)

    Alvarez, G.

    2009-09-01

    The purpose of this paper is (i) to present a generic and fully functional implementation of the density-matrix renormalization group (DMRG) algorithm, and (ii) to describe how to write additional strongly-correlated electron models and geometries by using templated classes. Besides considering general models and geometries, the code implements Hamiltonian symmetries in a generic way and parallelization over symmetry-related matrix blocks. Program summaryProgram title: DMRG++ Catalogue identifier: AEDJ_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEDJ_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: See file LICENSE No. of lines in distributed program, including test data, etc.: 15 795 No. of bytes in distributed program, including test data, etc.: 83 454 Distribution format: tar.gz Programming language: C++, MPI Computer: PC, HP cluster Operating system: Any, tested on Linux Has the code been vectorized or parallelized?: Yes RAM: 1 GB (256 MB is enough to run included test) Classification: 23 External routines: BLAS and LAPACK Nature of problem: Strongly correlated electrons systems, display a broad range of important phenomena, and their study is a major area of research in condensed matter physics. In this context, model Hamiltonians are used to simulate the relevant interactions of a given compound, and the relevant degrees of freedom. These studies rely on the use of tight-binding lattice models that consider electron localization, where states on one site can be labeled by spin and orbital degrees of freedom. The calculation of properties from these Hamiltonians is a computational intensive problem, since the Hilbert space over which these Hamiltonians act grows exponentially with the number of sites on the lattice. Solution method: The DMRG is a numerical variational technique to study quantum many body Hamiltonians. For one-dimensional and quasi one-dimensional systems, the

  4. A matrix model for valuing anesthesia service with the resource-based relative value system

    Directory of Open Access Journals (Sweden)

    Sinclair DR

    2014-10-01

    Full Text Available David R Sinclair,1 David A Lubarsky,1 Michael M Vigoda,1 David J Birnbach,1 Eric A Harris,1 Vicente Behrens,1 Richard E Bazan,1 Steve M Williams,1 Kristopher Arheart,2 Keith A Candiotti1 1Department of Anesthesiology, Perioperative Medicine and Pain Management, 2Department of Public Health Sciences, Division of Biostatistics, University of Miami Miller School of Medicine, Miami, FL, USA Background: The purpose of this study was to propose a new crosswalk using the resource-based relative value system (RBRVS that preserves the time unit component of the anesthesia service and disaggregates anesthesia billing into component parts (preoperative evaluation, intraoperative management, and postoperative evaluation. The study was designed as an observational chart and billing data review of current and proposed payments, in the setting of a preoperative holing area, intraoperative suite, and post anesthesia care unit. In total, 1,195 charts of American Society of Anesthesiology (ASA physical status 1 through 5 patients were reviewed. No direct patient interventions were undertaken. Results: Spearman correlations between the proposed RBRVS billing matrix payments and the current ASA relative value guide methodology payments were strong (r=0.94–0.96, P<0.001 for training, test, and overall. The proposed RBRVS-based billing matrix yielded payments that were 3.0%±1.34% less than would have been expected from commercial insurers, using standard rates for commercial ASA relative value units and RBRVS relative value units. Compared with current Medicare reimbursement under the ASA relative value guide, reimbursement would almost double when converting to an RBRVS billing model. The greatest increases in Medicare reimbursement between the current system and proposed billing model occurred as anesthetic management complexity increased. Conclusion: The new crosswalk correlates with existing evaluation and management and intensive care medicine codes in an

  5. Radiative transfer solutions for coupled atmosphere ocean systems using the matrix operator technique

    Science.gov (United States)

    Hollstein, André; Fischer, Jürgen

    2012-05-01

    Accurate radiative transfer models are the key tools for the understanding of radiative transfer processes in the atmosphere and ocean, and for the development of remote sensing algorithms. The widely used scalar approximation of radiative transfer can lead to errors in calculated top of atmosphere radiances. We show results with errors in the order of±8% for atmosphere ocean systems with case one waters. Variations in sea water salinity and temperature can lead to variations in the signal of similar magnitude. Therefore, we enhanced our scalar radiative transfer model MOMO, which is in use at Freie Universität Berlin, to treat these effects as accurately as possible. We describe our one-dimensional vector radiative transfer model for an atmosphere ocean system with a rough interface. We describe the matrix operator scheme and the bio-optical model for case one waters. We discuss some effects of neglecting polarization in radiative transfer calculations and effects of salinity changes for top of atmosphere radiances. Results are shown for the channels of the satellite instruments MERIS and OLCI from 412.5 nm to 900 nm.

  6. Classical integrable systems and soliton equations related to eleven-vertex R-matrix

    Energy Technology Data Exchange (ETDEWEB)

    Levin, A., E-mail: alevin@hse.ru [NRU HSE, Department of Mathematics, Myasnitskaya str. 20, Moscow, 101000 (Russian Federation); ITEP, B. Cheremushkinskaya str. 25, Moscow, 117218 (Russian Federation); Olshanetsky, M., E-mail: olshanet@itep.ru [ITEP, B. Cheremushkinskaya str. 25, Moscow, 117218 (Russian Federation); MIPT, Institutskii per. 9, Dolgoprudny, Moscow Region, 141700 (Russian Federation); Zotov, A., E-mail: zotov@mi.ras.ru [Steklov Mathematical Institute RAS, Gubkina str. 8, Moscow, 119991 (Russian Federation); ITEP, B. Cheremushkinskaya str. 25, Moscow, 117218 (Russian Federation); MIPT, Institutskii per. 9, Dolgoprudny, Moscow Region, 141700 (Russian Federation)

    2014-10-15

    In our recent paper we suggested a natural construction of the classical relativistic integrable tops in terms of the quantum R-matrices. Here we study the simplest case – the 11-vertex R-matrix and related gl{sub 2} rational models. The corresponding top is equivalent to the 2-body Ruijsenaars–Schneider (RS) or the 2-body Calogero–Moser (CM) model depending on its description. We give different descriptions of the integrable tops and use them as building blocks for construction of more complicated integrable systems such as Gaudin models and classical spin chains (periodic and with boundaries). The known relation between the top and CM (or RS) models allows to rewrite the Gaudin models (or the spin chains) in the canonical variables. Then they assume the form of n-particle integrable systems with 2n constants. We also describe the generalization of the top to 1+1 field theories. It allows us to get the Landau–Lifshitz type equation. The latter can be treated as non-trivial deformation of the classical continuous Heisenberg model. In a similar way the deformation of the principal chiral model is described.

  7. Classical integrable systems and soliton equations related to eleven-vertex R-matrix

    Directory of Open Access Journals (Sweden)

    A. Levin

    2014-10-01

    Full Text Available In our recent paper we suggested a natural construction of the classical relativistic integrable tops in terms of the quantum R-matrices. Here we study the simplest case – the 11-vertex R-matrix and related gl2 rational models. The corresponding top is equivalent to the 2-body Ruijsenaars–Schneider (RS or the 2-body Calogero–Moser (CM model depending on its description. We give different descriptions of the integrable tops and use them as building blocks for construction of more complicated integrable systems such as Gaudin models and classical spin chains (periodic and with boundaries. The known relation between the top and CM (or RS models allows to rewrite the Gaudin models (or the spin chains in the canonical variables. Then they assume the form of n-particle integrable systems with 2n constants. We also describe the generalization of the top to 1+1 field theories. It allows us to get the Landau–Lifshitz type equation. The latter can be treated as non-trivial deformation of the classical continuous Heisenberg model. In a similar way the deformation of the principal chiral model is described.

  8. Development of an integrated system for activity-based profiling of matrix metallo-proteases

    NARCIS (Netherlands)

    Freije, Jan Robert

    2006-01-01

    Matrix metallo-proteases constitute a family of extracellular zinc-dependent endopeptidases that are involved in degradation of extracellular matrix (ECM) components and other bioactive non-ECM molecules. A plethora of studies have implicated important roles for MMPs in many diseases (including canc

  9. All-trans retinoic acid regulates the expression of the extracellular matrix protein fibulin-1 in the guinea pig sclera and human scleral fibroblasts

    OpenAIRE

    Li, Chuanxu; McFadden, Sally A.; Morgan, Ian; Cui, Dongmei; Hu, Jianmin; Wan, Wenjuan; Zeng, Junwen

    2010-01-01

    Purpose Fibulin-1 (FBLN1) mRNA is expressed in human sclera and is an important adhesion modulatory protein that can affect cell–matrix interactions and tissue remodeling. Scleral remodeling is influenced by all-trans retinoic acid (RA). Our purpose was to confirm the presence of fibulin-1 protein in guinea pig sclera and investigate the effect of RA on the expression of fibulin-1 in guinea pig sclera in vivo and in cultured human scleral fibroblasts (HSFs). Methods Confocal fluorescence micr...

  10. Design of Luenberger function observer with disturbance decoupling for matrix second-order linear systems-a parametric approach

    Institute of Scientific and Technical Information of China (English)

    Wu Yunli; Duan Guangren

    2006-01-01

    A simple method for disturbance decoupling for matrix second-order linear systems is proposed directly in matrix second-order framework via Luenberger function observers based on complete parametric eigenstructure assignment.By introducing the H2 norm of the transfer function from disturbance to estimation error, sufficient and necessary conditions for disturbance decoupling in matrix second-order linear systems are established and are arranged into constraints on the design parameters via Luenberger function observers in terms of the closed-loop eigenvalues and the group of design parameters provided by the eigenstructure assignment approach. Therefore, the disturbance decoupling problem is converted into an eigenstructure assignment problem with extra parameter constraints. A simple example is investigated to show the effect and simplicity of the approach.

  11. Human amnion membrane matrix as a substratum for axonal regeneration in the central nervous system.

    Science.gov (United States)

    Gage, F H; Blaker, S N; Davis, G E; Engvall, E; Varon, S; Manthorpe, M

    1988-01-01

    Human Amnion Membrane Matrix (HAMM) was used as a substratum for the regeneration of neuronal axons in the central nervous system. A large piece of HAMM was bound to nitrocellulose paper (NCP) as a supporting material, and cut into small strips. Aspirative lesions of the fimbria-fornix were made in adult rats leaving a cavity separating the septum from the hippocampus. In the same operation a small piece of HAMM-NCP was placed into the cavity with one end abutting the axotomized septum and the other end abutting the denervated hippocampus. At times between 2 weeks and 3 months after surgery the brains of the animals were examined histologically for 1) host response to the implant; 2) maintenance of HAMM-NCP in the originally implanted orientation; 3) growth of acetylcholinesterase (AChE)-positive fibers on the HAMM; 4) growth of the AChE-positive fibers into the denervated hippocampus; and 5) non-neuronal cells on the HAMM. The NCP remained in place over the 3-month period. In most cases the HAMM and NCP remained apposed and caused no greater reaction in the brain beyond that created in response to the aspirative lesion alone. AChE-positive fibers grew out from the septum onto the HAMM by 2 weeks, and by 8 weeks more extensive growth was observed on the HAMM. By 8-weeks, AChE fibers could be clearly seen coming off the membrane and entering the host hippocampus. By double-labelling for the basement membrane side of the HAMM (using anti-human laminin antibodies) and for cholinergic fibers (using AChE histochemistry) in the same sections, it was possible to see fibers clearly growing on the laminin-positive side of the HAMM but little or no growth on the opposing laminin-negative stromal side. The most important variables for extensive growth appeared to be the accurate placement of the implant and the amount of time following the lesions. The placement of the matrix on NCP prior to implantation in the brain made it easier to orient the membrane between the septum

  12. The Usefulness of Performance Matrix Tests in Locomotor System Evaluation of Girls Attending a Ballet School — Preliminary Observation

    OpenAIRE

    Wójcik, Małgorzata; Siatkowski, Idzi

    2014-01-01

    [Purpose] Learning ballet is connected with continuous use of the locomotor system while subjecting it to high loads. Therefore, we conducted some research defining the appearance of weak links in the motor system, in order to eliminate the risk of injury. [Methods] Fifty-two female students of a ballet school were examined. To identify weak links, low-threshold Performance Matrix tests were performed. An analysis of weak link occurrence in the locomotor system was carried out, using two way ...

  13. Systems interaction results from the digraph matrix analysis of the Watts Bar Nuclear Power Plant high pressure safety injection systems. Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    Sacks, I.J.; Ashmore, B.C.; Alesso, H.P.

    1983-07-01

    Spatial and functional coupling (including human actions) of nuclear power plant systems that lead to interdependencies are called Systems Interactions. At present, the US Nuclear Regulatory Commission (NRC) is investigating ways of integrating a systems interactions study with existing Probabilistic Risk Assessment efforts. One approach is based on graph-theoretic methods utilizing matrix representations of logic diagrams called Digraph Matrix Analysis (DMA). The objective in this report is to demonstrate the capabilities of Digraph Matrix Analysis to model an accident sequence (including front-line systems, support systems and human actions) as a continuous, well-integrated logic model in order to identify and evaluate functional systems interactions. The selected accident sequence, loss of high pressure safety injection during a LOCA, was modeled and qualitative and quantitative comparisons were made to the Reactor Safety Study (WASH 1400) and other studies.

  14. Systems interaction results from the digraph matrix analysis of the Watts Bar Nuclear Power Plant high pressure safety injection systems. Volume 2

    Energy Technology Data Exchange (ETDEWEB)

    Sacks, I.J.; Ashmore, B.C.; Alesso, H.P.

    1983-07-01

    Spatial and functional coupling of nuclear power plant systems that lead to interdependencies are called Systems Interactions. At present, the US Nuclear Regulatory Commission (NRC) is investigating ways of integrating a systems interactions study with existing Probabilistic Risk Assessment efforts. One approach is based on graph-theoretic methods utilizing matrix representations of logic diagrams called Digraph Matrix Analysis (DMA). The objective in this report is to demonstrate the capabilities of Digraph Matrix Analysis to model an accident sequence (including front line systems, support systems and human actions) as a continuous, well-integrated logic model in order to identify and evaluate functional systems interactions. The selected accident sequence, loss of high pressure safety injection during an S1 LOCA, was modeled and qualitative and quantitative comparisons were made to WASH 1400 aand other studies.

  15. Identification of a novel system L amino acid transporter structurally distinct from heterodimeric amino acid transporters.

    Science.gov (United States)

    Babu, Ellappan; Kanai, Yoshikatsu; Chairoungdua, Arthit; Kim, Do Kyung; Iribe, Yuji; Tangtrongsup, Sahatchai; Jutabha, Promsuk; Li, Yuewei; Ahmed, Nesar; Sakamoto, Shinichi; Anzai, Naohiko; Nagamori, Seishi; Endou, Hitoshi

    2003-10-31

    A cDNA that encodes a novel Na+-independent neutral amino acid transporter was isolated from FLC4 human hepatocarcinoma cells by expression cloning. When expressed in Xenopus oocytes, the encoded protein designated LAT3 (L-type amino acid transporter 3) transported neutral amino acids such as l-leucine, l-isoleucine, l-valine, and l-phenylalanine. The LAT3-mediated transport was Na+-independent and inhibited by 2-aminobicyclo[2.2.1]heptane-2-carboxylic acid, consistent with the properties of system L. Distinct from already known system L transporters LAT1 and LAT2, which form heterodimeric complex with 4F2 heavy chain, LAT3 was functional by itself in Xenopus oocytes. The deduced amino acid sequence of LAT3 was identical to the gene product of POV1 reported as a prostate cancer-up-regulated gene whose function was not determined, whereas it did not exhibit significant similarity to already identified transporters. The Eadie-Hofstee plots of LAT3-mediated transport were curvilinear, whereas the low affinity component is predominant at physiological plasma amino acid concentration. In addition to amino acid substrates, LAT3 recognized amino acid alcohols. The transport of l-leucine was electroneutral and mediated by a facilitated diffusion. In contrast, l-leucinol, l-valinol, and l-phenylalaninol, which have a net positive charge induced inward currents under voltage clamp, suggesting these compounds are transported by LAT3. LAT3-mediated transport was inhibited by the pretreatment with N-ethylmaleimide, consistent with the property of system L2 originally characterized in hepatocyte primary culture. Based on the substrate selectivity, affinity, and N-ethylmaleimide sensitivity, LAT3 is proposed to be a transporter subserving system L2. LAT3 should denote a new family of organic solute transporters. PMID:12930836

  16. Modeling State-Space Aeroelastic Systems Using a Simple Matrix Polynomial Approach for the Unsteady Aerodynamics

    Science.gov (United States)

    Pototzky, Anthony S.

    2008-01-01

    A simple matrix polynomial approach is introduced for approximating unsteady aerodynamics in the s-plane and ultimately, after combining matrix polynomial coefficients with matrices defining the structure, a matrix polynomial of the flutter equations of motion (EOM) is formed. A technique of recasting the matrix-polynomial form of the flutter EOM into a first order form is also presented that can be used to determine the eigenvalues near the origin and everywhere on the complex plane. An aeroservoelastic (ASE) EOM have been generalized to include the gust terms on the right-hand side. The reasons for developing the new matrix polynomial approach are also presented, which are the following: first, the "workhorse" methods such as the NASTRAN flutter analysis lack the capability to consistently find roots near the origin, along the real axis or accurately find roots farther away from the imaginary axis of the complex plane; and, second, the existing s-plane methods, such as the Roger s s-plane approximation method as implemented in ISAC, do not always give suitable fits of some tabular data of the unsteady aerodynamics. A method available in MATLAB is introduced that will accurately fit generalized aerodynamic force (GAF) coefficients in a tabular data form into the coefficients of a matrix polynomial form. The root-locus results from the NASTRAN pknl flutter analysis, the ISAC-Roger's s-plane method and the present matrix polynomial method are presented and compared for accuracy and for the number and locations of roots.

  17. GLYCOLIC-NITRIC ACID FLOWSHEET DEMONSTRATION OF THE DWPF CHEMICAL PROCESSING CELL WITH MATRIX SIMULANTS AND SUPERNATE

    Energy Technology Data Exchange (ETDEWEB)

    Lambert, D.; Stone, M.; Newell, J.; Best, D.

    2012-05-07

    Savannah River Remediation (SRR) is evaluating changes to its current DWPF flowsheet to improve processing cycle times. This will enable the facility to support higher canister production while maximizing waste loading. Higher throughput is needed in the CPC since the installation of the bubblers into the melter has increased melt rate. Due to the significant maintenance required for the DWPF gas chromatographs (GC) and the potential for production of flammable quantities of hydrogen, reducing or eliminating the amount of formic acid used in the CPC is being developed. Earlier work at Savannah River National Laboratory has shown that replacing formic acid with an 80:20 molar blend of glycolic and formic acids has the potential to remove mercury in the SRAT without any significant catalytic hydrogen generation. This report summarizes the research completed to determine the feasibility of processing without formic acid. In earlier development of the glycolic-formic acid flowsheet, one run (GF8) was completed without formic acid. It is of particular interest that mercury was successfully removed in GF8, no formic acid at 125% stoichiometry. Glycolic acid did not show the ability to reduce mercury to elemental mercury in initial screening studies, which is why previous testing focused on using the formic/glycolic blend. The objective of the testing detailed in this document is to determine the viability of the nitric-glycolic acid flowsheet in processing sludge over a wide compositional range as requested by DWPF. This work was performed under the guidance of Task Technical and Quality Assurance Plan (TT and QAP). The details regarding the simulant preparation and analysis have been documented previously.

  18. Release of salicylic acid, diclofenac acid and diclofenac acid salts from isotropic and anisotropic nonionic surfactant systems across rat skin.

    Science.gov (United States)

    Gabboun, N H; Najib, N M; Ibrahim, H G; Assaf, S

    2001-01-01

    Release of salicylic acid, diclofenac acid, diclofenac diethylamine and diclofenac sodium, from lyotropic structured systems, namely; neat and middle liquid crystalline phases, across mid-dorsal hairless rat skin into aqueous buffer were studied. Release results were compared with those from the isotropic systems. The donor systems composed of the surfactant polyoxyethylene (20) isohexadecyl ether, HCl buffer of pH 1 or distilled water and the specific drug. High performance liquid chromatography (HPLC) methods were used to monitor the transfer of the drugs across the skin barrier. Results indicated that the rate-determining step in the transport process was the release of the drug from the specified donor system. Further, apparent zero order release was demonstrated with all systems. Except for diclofenac sodium, drug fluxes decreased as the donor medium changed from isotropic to anisotropic. The decrease in fluxes was probably due to the added constrains on the movement of drug molecules. By changing the anisotropic donor medium from neat to middle phase, drug flux decreased in case of salicylic acid and diclofenac sodium. In the mean time, flux increased in case of the diethylamine salt and appeared nearly similar in case of diclofenac acid. Rates of drug transfer across the skin from the anisotropic donors seemed to be largely controlled by the entropy contribution to the transport process. The type and extent of drug-liquid crystal interactions probably influenced the latter.

  19. Comparison between Unknown Input Estimation of a System Using Projection Operator Approach and Generalized Matrix Inverse Method

    Directory of Open Access Journals (Sweden)

    Ashis De

    2014-01-01

    Full Text Available In this paper a detailed comparison between the estimation results of unknown inputs of a linear time invariant system using projection operator approach and using the method of generalized matrix inverse have been discussed. The full order observer constructed using projection operator approach has been extended and implemented for this purpose.

  20. Coordinated Control for Flywheel Energy Storage Matrix Systems for Wind Farm Based on Charging/Discharging Ratio Consensus Algorithms

    DEFF Research Database (Denmark)

    Cao, Qian; Song, Y. D.; Guerrero, Josep M.;

    2016-01-01

    This paper proposes a distributed algorithm for coordination of flywheel energy storage matrix system (FESMS) cooperated with wind farm. A simple and distributed ratio consensus algorithm is proposed to solve FESMS dispatch problem. The algorithm is based on average consensus for both undirected...

  1. Influence of matrix systems on proximal contact tightness of 2- and 3-surface posterior composite restorations in vivo

    NARCIS (Netherlands)

    Wirsching, E.; Loomans, B.A.C.; Klaiber, B.; Dorfer, C.E.

    2011-01-01

    OBJECTIVES: To investigate the influence of cavity preparation (MO/DO/MOD) and type of matrix system on proximal contact tightness of direct posterior composite restorations. MATERIALS AND METHODS: 85 patients in need of a two- or three surface Class II direct composite restoration were randomly div

  2. Blade system design studies volume II : preliminary blade designs and recommended test matrix.

    Energy Technology Data Exchange (ETDEWEB)

    Griffin, Dayton A. (Global Energy Concepts, LLC, Kirkland, WA)

    2004-06-01

    As part of the U.S. Department of Energy's Wind Partnerships for Advanced Component Technologies (WindPACT) program, Global Energy Concepts, LLC is performing a Blade System Design Study (BSDS) concerning innovations in materials, processes and structural configurations for application to wind turbine blades in the multi-megawatt range. The BSDS Volume I project report addresses issues and constraints identified to scaling conventional blade designs to the megawatt size range, and evaluated candidate materials, manufacturing and design innovations for overcoming and improving large blade economics. The current report (Volume II), presents additional discussion of materials and manufacturing issues for large blades, including a summary of current trends in commercial blade manufacturing. Specifications are then developed to guide the preliminary design of MW-scale blades. Using preliminary design calculations for a 3.0 MW blade, parametric analyses are performed to quantify the potential benefits in stiffness and decreased gravity loading by replacement of a baseline fiberglass spar with carbon-fiberglass hybrid material. Complete preliminary designs are then presented for 3.0 MW and 5.0 MW blades that incorporate fiberglass-to-carbon transitions at mid-span. Based on analysis of these designs, technical issues are identified and discussed. Finally, recommendations are made for composites testing under Part I1 of the BSDS, and the initial planned test matrix for that program is presented.

  3. System and method for the adaptive mapping of matrix data to sets of polygons

    Science.gov (United States)

    Burdon, David (Inventor)

    2003-01-01

    A system and method for converting bitmapped data, for example, weather data or thermal imaging data, to polygons is disclosed. The conversion of the data into polygons creates smaller data files. The invention is adaptive in that it allows for a variable degree of fidelity of the polygons. Matrix data is obtained. A color value is obtained. The color value is a variable used in the creation of the polygons. A list of cells to check is determined based on the color value. The list of cells to check is examined in order to determine a boundary list. The boundary list is then examined to determine vertices. The determination of the vertices is based on a prescribed maximum distance. When drawn, the ordered list of vertices create polygons which depict the cell data. The data files which include the vertices for the polygons are much smaller than the corresponding cell data files. The fidelity of the polygon representation can be adjusted by repeating the logic with varying fidelity values to achieve a given maximum file size or a maximum number of vertices per polygon.

  4. Multireference linearized Coupled Cluster theory for strongly correlated systems using Matrix Product States

    CERN Document Server

    Sharma, Sandeep

    2015-01-01

    We propose a multireference linearized coupled cluster theory using matrix product states (MPS-LCC) which provides remarkably accurate ground-state energies, at a computational cost that has the same scaling as multireference configuration interaction singles and doubles (MRCISD), for a wide variety of electronic Hamiltonians. These range from first-row dimers at equilibrium and stretched geometries, to highly multireference systems such as the chromium dimer and lattice models such as periodic two-dimensional 1-band and 3-band Hubbard models. The MPS-LCC theory shows a speed up of several orders of magnitude over the usual DMRG algorithm while delivering energies in excellent agreement with converged DMRG calculations. Also, in all the benchmark calculations presented here MPS-LCC outperformed the commonly used multi-reference quantum chemistry methods in some cases giving energies in excess of an order of magnitude more accurate. As a size-extensive method that can treat large active spaces, MPS-LCC opens u...

  5. The Spin Density Matrix II: Application to a system of two quantum dots

    CERN Document Server

    Kunikeev, Sharif D

    2007-01-01

    This work is a sequel to our work "The Spin Density Matrix I: General Theory and Exact Master Equations" (eprint cond-mat/0708.0644). Here we compare pure- and pseudo-spin dynamics using as an example a system of two quantum dots, a pair of localized conduction-band electrons in an n-doped GaAs semiconductor. Pure-spin dynamics is obtained by tracing out the orbital degrees of freedom, whereas pseudo-spin dynamics retains (as is conventional) an implicit coordinate dependence. We show that magnetic field inhomogeneity and spin-orbit interaction result in a non-unitary evolution in pure-spin dynamics, whereas these interactions contribute to the effective pseudo-spin Hamiltonian via terms that are asymmetric in spin permutations, in particular, the Dzyaloshinskii-Moriya (DM) spin-orbit interaction. We numerically investigate the non-unitary effects in the dynamics of the triplet states population, purity, and Lamb energy shift, as a function of interdot distance and magnetic field difference. The spin-orbit in...

  6. Matrix-product-state method with local basis optimization for nonequilibrium electron-phonon systems

    Science.gov (United States)

    Heidrich-Meisner, Fabian; Brockt, Christoph; Dorfner, Florian; Vidmar, Lev; Jeckelmann, Eric

    We present a method for simulating the time evolution of quasi-one-dimensional correlated systems with strongly fluctuating bosonic degrees of freedom (e.g., phonons) using matrix product states. For this purpose we combine the time-evolving block decimation (TEBD) algorithm with a local basis optimization (LBO) approach. We discuss the performance of our approach in comparison to TEBD with a bare boson basis, exact diagonalization, and diagonalization in a limited functional space. TEBD with LBO can reduce the computational cost by orders of magnitude when boson fluctuations are large and thus it allows one to investigate problems that are out of reach of other approaches. First, we test our method on the non-equilibrium dynamics of a Holstein polaron and show that it allows us to study the regime of strong electron-phonon coupling. Second, the method is applied to the scattering of an electronic wave packet off a region with electron-phonon coupling. Our study reveals a rich physics including transient self-trapping and dissipation. Supported by Deutsche Forschungsgemeinschaft (DFG) via FOR 1807.

  7. Chondroitin sulphate proteoglycans: extracellular matrix proteins that regulate immunity of the central nervous system.

    Science.gov (United States)

    Haylock-Jacobs, Sarah; Keough, Michael B; Lau, Lorraine; Yong, V Wee

    2011-10-01

    The extracellular matrix (ECM) is a complex network of scaffolding molecules that also plays an important role in cell signalling, migration and tissue structure. In the central nervous system (CNS), the ECM is integral to the efficient development/guidance and survival of neurons and axons. However, changes in distribution of the ECM in the CNS may significantly enhance pathology in CNS disease or following injury. One group of ECM proteins that is important for CNS homeostasis is the chondroitin sulphate proteoglycans (CSPGs). Up-regulation of these molecules has been demonstrated to be both desirable and detrimental following CNS injury. Taking cues from arthritis, where there is a strong anti-CSPG immune response, there is evidence that suggests that CSPGs may influence immunity during CNS pathological conditions. This review focuses on the role of CSPGs in CNS pathologies as well as in immunity, both from a viewpoint of how they may inhibit repair and exacerbate damage in the CNS, and how they are involved in activation and function of peripheral immune cells, particularly in multiple sclerosis. Lastly, we address how CSPGs may be manipulated to improve disease outcomes.

  8. Cells must express components of the planar cell polarity system and extracellular matrix to support cytonemes

    Science.gov (United States)

    Huang, Hai; Kornberg, Thomas B

    2016-01-01

    Drosophila dorsal air sac development depends on Decapentaplegic (Dpp) and Fibroblast growth factor (FGF) proteins produced by the wing imaginal disc and transported by cytonemes to the air sac primordium (ASP). Dpp and FGF signaling in the ASP was dependent on components of the planar cell polarity (PCP) system in the disc, and neither Dpp- nor FGF-receiving cytonemes extended over mutant disc cells that lacked them. ASP cytonemes normally navigate through extracellular matrix (ECM) composed of collagen, laminin, Dally and Dally-like (Dlp) proteins that are stratified in layers over the disc cells. However, ECM over PCP mutant cells had reduced levels of laminin, Dally and Dlp, and whereas Dpp-receiving ASP cytonemes navigated in the Dally layer and required Dally (but not Dlp), FGF-receiving ASP cytonemes navigated in the Dlp layer, requiring Dlp (but not Dally). These findings suggest that cytonemes interact directly and specifically with proteins in the stratified ECM. DOI: http://dx.doi.org/10.7554/eLife.18979.001 PMID:27591355

  9. Furan Occurrence in Starchy Food Model Systems Processed at High Temperatures: Effect of Ascorbic Acid and Heating Conditions

    DEFF Research Database (Denmark)

    Mariotti, María; Granby, Kit; Fromberg, Arvid;

    2012-01-01

    Furan, a potential carcinogen, has been detected in highly consumed starchy foods, such as bread and snacks; however, research on furan generation in these food matrixes has not been undertaken, thus far. The present study explored the effect of ascorbic acid addition and cooking methods (frying...... and baking) over furan occurrence and its relation with the non-enzymatic browning in a wheat flour starchy food model system. Results showed that furan generation significantly increased in the presence of ascorbic acid after 7 min of heating (p

  10. Downregulation of membrane type-matrix metalloproteinases in the inflamed or injured central nervous system

    Directory of Open Access Journals (Sweden)

    Millward Jason M

    2007-09-01

    Full Text Available Abstract Background Matrix metalloproteinases (MMPs are thought to mediate cellular infiltration in central nervous system (CNS inflammation by cleaving extracellular matrix proteins associated with the blood-brain barrier. The family of MMPs includes 23 proteinases, including six membrane type-MMPs (MT-MMPs. Leukocyte infiltration is an integral part of the pathogenesis of autoimmune inflammation in the CNS, as occurs in multiple sclerosis and its animal model experimental autoimmune encephalomyelitis (EAE, as well as in the response to brain trauma and injury. We have previously shown that gene expression of the majority of MMPs was upregulated in the spinal cord of SJL mice with severe EAE induced by adoptive transfer of myelin basic protein-reactive T cells, whereas four of the six MT-MMPs (MMP-15, 16, 17 and 24 were downregulated. The two remaining MT-MMPs (MMP-14 and 25 were upregulated in whole tissue. Methods We used in vivo models of CNS inflammation and injury to study expression of MT-MMP and cytokine mRNA by real-time RT-PCR. Expression was also assessed in microglia sorted from CNS by flow cytometry, and in primary microglia cultures following treatment with IFNγ. Results We now confirm the expression pattern of MT-MMPs in the B6 mouse, independent of effects of adjuvant. We further show expression of all the MT-MMPs, except MMP-24, in microglia. Microglia isolated from mice with severe EAE showed statistically significant downregulation of MMP-15, 17 and 25 and lack of increase in levels of other MT-MMPs. Downregulation of MT-MMPs was also apparent following CNS injury. The pattern of regulation of MT-MMPs in neuroinflammation showed no association with expression of the proinflammatory cytokines TNFα, IL-1β, or IFNγ. Conclusion CNS inflammation and injury leads to downregulation in expression of the majority of MT-MMPs. Microglia in EAE showed a general downregulation of MT-MMPs, and our findings suggest that MT-MMP levels may

  11. Effect of pioglitazone, quercetin and hydroxy citric acid on extracellular matrix components in experimentally induced non-alcoholic steatohepatitis

    Directory of Open Access Journals (Sweden)

    Surapaneni Krishna Mohan

    2015-08-01

    Results:The experimental NASH rats treated with pioglitazone showed significant decrease in the levels of hyaluronic acid and significant increase in adiponectin levels when compared to experimentally induced NASH group, but did not show any effect on the levels of leptin. Contrary to these two drugs, viz. pioglitazone and hydroxy citric acid, the group treated with quercetin showedsignificant decrease in the levels of hyaluronic acid and leptin and significant decrease in adiponectin levels compared with that of experimentally induced NASH NASH group, offering maximum protection against NASH. Conclusion: Considering our findings, it could be concluded that quercetin may offer maximum protection against NASH by significantly increasing the levels of adiponectin, when compared to pioglitazone and hydroxy citric acid.

  12. Research on development of in situ titanium matrix composites and in situ reaction thermodynamics of the reaction systems

    Institute of Scientific and Technical Information of China (English)

    Lifang Cai; Yongzhong Zhang; Likai Shi; Haoqiang Yang; Mingzhe Xi

    2006-01-01

    The in situ synthesis method for titanium matrix composites (TMCs) has obvious technical and economical advantages over other traditional methods. Ultrafine reinforcement particles were formed in situ by chemical reaction between elements or between elements and compounds. Using the approach, contamination at the composite matrix/reinforcement particle interface did not occur,interface bonding was good, and the reinforcement particle was thermodynamically stable. The stage of development of the preparation process for in situ TMCs as well as the thermodynamic analysis of the possible in situ reaction systems was described.

  13. Geometrical construction of the S matrix and multichannel quantum defect theory for the two open and one closed channel system

    CERN Document Server

    Lee, C W

    2002-01-01

    The multichannel quantum defect theory (MQDT) is reformulated into the form of the configuration mixing (CM) method using the geometrical construction of the S matrix developed for the system involving two open and one closed channels. The reformulation is done by the phase renormalization method of Giusti-Suzor and Fano. The rather unconventional short-range reactance matrix K whose diagonal elements are not zero is obtained though the Lu-Fano plot becomes symmetrical. The reformulation of MQDT yields the partial cross section formulas analogous to Fano's resonance formula, which has not easily been available in other's work.

  14. Geometrical construction of the S matrix and multichannel quantum defect theory for the two open and one closed channel system

    International Nuclear Information System (INIS)

    The multichannel quantum defect theory (MQDT) is reformulated into the form of the configuration mixing (CM) method using the geometrical construction of the S matrix developed for the system involving two open and one closed channels. The reformulation is done by the phase renormalization method of Giusti-Suzor and Fano. The rather unconventional short-range reactance matrix K whose diagonal elements are not zero is obtained though the Lu-Fano plot becomes symmetrical. The reformulation of MQDT yields the partial cross section formulas analogous to Fano's resonance formula, which has not easily been available in other's work

  15. Microbial Nucleic Acid Sensing in Oral and Systemic Diseases.

    Science.gov (United States)

    Crump, K E; Sahingur, S E

    2016-01-01

    One challenge in studying chronic infectious and inflammatory disorders is understanding how host pattern recognition receptors (PRRs), specifically toll-like receptors (TLRs), sense and respond to pathogen- or damage-associated molecular patterns, their communication with each other and different components of the immune system, and their role in propagating inflammatory stages of disease. The discovery of innate immune activation through nucleic acid recognition by intracellular PRRs such as endosomal TLRs (TLR3, TLR7, TLR8, and TLR9) and cytoplasmic proteins (absent in melanoma 2 and DNA-dependent activator of interferon regulatory factor) opened a new paradigm: Nucleic acid sensing is now implicated in multiple immune and inflammatory conditions (e.g., atherosclerosis, cancer), viral (e.g., human papillomavirus, herpes virus) and bacterial (e.g., Helicobacter pylori, pneumonia) diseases, and autoimmune disorders (e.g., systemic lupus erythematosus, rheumatoid arthritis). Clinical investigations reveal the overexpression of specific nucleic acid sensors in diseased tissues. In vivo animal models show enhanced disease progression associated with receptor activation. The involvement of nucleic acid sensors in various systemic conditions is further supported by studies reporting receptor knockout mice being either protected from or prone to disease. TLR9-mediated inflammation is also implicated in periodontal diseases. Considering that persistent inflammation in the oral cavity is associated with systemic diseases and that oral microbial DNA is isolated at distal sites, nucleic acid sensing may potentially be a link between oral and systemic diseases. In this review, we discuss recent advances in how intracellular PRRs respond to microbial nucleic acids and emerging views on the role of nucleic acid sensors in various systemic diseases. We also highlight new information on the role of intracellular PRRs in the pathogenesis of oral diseases including periodontitis

  16. 21 CFR 862.1320 - Gastric acidity test system.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Gastric acidity test system. 862.1320 Section 862.1320 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems §...

  17. 21 CFR 862.1290 - Fatty acids test system.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Fatty acids test system. 862.1290 Section 862.1290 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems §...

  18. 21 CFR 862.1095 - Ascorbic acid test system.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ascorbic acid test system. 862.1095 Section 862.1095 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems §...

  19. Throughput-Distortion Computation Of Generic Matrix Multiplication: Toward A Computation Channel For Digital Signal Processing Systems

    CERN Document Server

    Anastasia, Davide

    2011-01-01

    The generic matrix multiply (GEMM) function is the core element of high-performance linear algebra libraries used in many computationally-demanding digital signal processing (DSP) systems. We propose an acceleration technique for GEMM based on dynamically adjusting the imprecision (distortion) of computation. Our technique employs adaptive scalar companding and rounding to input matrix blocks followed by two forms of packing in floating-point that allow for concurrent calculation of multiple results. Since the adaptive companding process controls the increase of concurrency (via packing), the increase in processing throughput (and the corresponding increase in distortion) depends on the input data statistics. To demonstrate this, we derive the optimal throughput-distortion control framework for GEMM for the broad class of zero-mean, independent identically distributed, input sources. Our approach converts matrix multiplication in programmable processors into a computation channel: when increasing the processi...

  20. Ranking of small scale proposals for water system repair using the Rapid Impact Assessment Matrix (RIAM)

    Energy Technology Data Exchange (ETDEWEB)

    Shakib-Manesh, T.E.; Hirvonen, K.O.; Jalava, K.J.; Ålander, T.; Kuitunen, M.T., E-mail: markku.kuitunen@jyu.fi

    2014-11-15

    Environmental impacts of small scale projects are often assessed poorly, or not assessed at all. This paper examines the usability of the Rapid Impact Assessment Matrix (RIAM) as a tool to prioritize project proposals for small scale water restoration projects in relation to proposals' potential to improve the environment. The RIAM scoring system was used to assess and rank the proposals based on their environmental impacts, the costs of the projects to repair the harmful impacts, and the size of human population living around the sites. A four-member assessment group (The expert panel) gave the RIAM-scores to the proposals. The assumed impacts of the studied projects at the Eastern Finland water systems were divided into the ecological and social impacts. The more detailed assessment categories of the ecological impacts in this study were impacts on landscape, natural state, and limnology. The social impact categories were impacts to recreational use of the area, fishing, industry, population, and economy. These impacts were scored according to their geographical and social significance, their magnitude of change, their character, permanence, reversibility, and cumulativeness. The RIAM method proved to be an appropriate and recommendable method for the small-scale assessment and prioritizing of project proposals. If the assessments are well documented, the RIAM can be a method for easy assessing and comparison of the various kinds of projects. In the studied project proposals there were no big surprises in the results: the best ranks were received by the projects, which were assumed to return watersheds toward their original state.

  1. Assessment of antimicrobial resistance transfer between lactic acid bacteria and potential foodborne pathogens using in vitro methods and mating in a food matrix.

    Science.gov (United States)

    Toomey, Niamh; Monaghan, Aine; Fanning, Séamus; Bolton, Declan J

    2009-10-01

    The transferability of antimicrobial resistance from lactic acid bacteria (LAB) to potential pathogenic strains was studied using in vitro methods and mating in a food matrix. Five LAB donors containing either erythromycin or tetracycline resistance markers on transferable elements were conjugally mated with LAB (Enterococcus faecalis, Lactococcus lactis) and pathogenic strains (Listeria spp., Salmonella ssp., Staphylococcus aureus, and Escherichia coli). In vitro transfer experiments were carried out with the donors and recipients using both the filter and plate mating methods. The food matrix consisted of fermented whole milk (fermented with the LAB donors) with the pathogenic recipients added as contaminants during the production process. All transconjugants were confirmed by phenotypic and molecular methods. Erythromycin resistance transfer from LAB strains to Listeria spp. was observed using both in vitro mating methods at high transfer frequencies of up to 5.1 x 10(-4) transconjugants per recipient. Also, high frequency transfer (ranging from 2.7 x 10(-8) up to 1.1 x 10(-3) transconjugants per recipient) of both erythromycin and tetracycline-resistance was observed between LAB species using in vitro methods. No resistance transfer was observed to Salmonella spp., Staphylococcus aureus, and E. coli. The only conjugal transfer observed in the fermented milk matrix was for tetracycline resistance between two LAB strains (at a transfer frequency of 2.6 x 10(-7) transconjugants per recipients). This study demonstrates the transfer of antimicrobial resistance from LAB to Listeria spp. using in vitro methods and also the transfer of resistance between LAB species in a food matrix. It highlights the involvement of LAB as a potential source of resistance determinants that may be disseminated between LAB and pathogenic strains including Listeria spp. Furthermore, it indicates that food matrices such as fermented milks may provide a suitable environment to support gene

  2. The Density Matrix Renormalization Group for Strongly Correlated Electron Systems: A Generic Implementation

    Energy Technology Data Exchange (ETDEWEB)

    Alvarez, Gonzalo [ORNL

    2009-01-01

    The purpose of this paper is (1) to present a generic and fully functional implementation of the density-matrix renormalization group (DMRG) algorithm, and (2) to describe how to write additional strongly-correlated electron models and geometries by using templated classes. Besides considering general models and geometries, the code implements Hamiltonian symmetries in a generic way and parallelization over symmetry-related matrix blocks.

  3. Dissolution state of cellulose in aqueous systems. 2. Acidic solvents.

    Science.gov (United States)

    Alves, Luis; Medronho, Bruno; Antunes, Filipe E; Topgaard, Daniel; Lindman, Björn

    2016-10-20

    Cellulose is insoluble in water but can be dissolved in strong acidic or alkaline conditions. How well dissolved cellulose is in solution and how it organizes are key questions often neglected in literature. The typical low pH required for dissolving cellulose in acidic solvents limits the use of typical characterization techniques. In this respect, Polarization Transfer Solid State NMR (PT ssNMR) emerges as a reliable alternative. In this work, combining PT ssNMR, microscopic techniques and X-ray diffraction, a set of different acidic systems (phosphoric acid/water, sulfuric acid/glycerol and zinc chloride/water) is investigated. The studied solvent systems are capable to efficiently dissolve cellulose, although degradation occurs to some extent. PT ssNMR is capable to identify the liquid and solid fractions of cellulose, the degradation products and it is also sensitive to gelation. The materials regenerated from the acidic dopes were found to be highly sensitive to the solvent system and to the presence of amphiphilic additives in solution. PMID:27474617

  4. Determination of optimal collimation parameters for a rotating slat collimator system: a system matrix method using ML-EM

    Science.gov (United States)

    Boisson, F.; Bekaert, V.; Brasse, D.

    2016-03-01

    Nowadays, Single Photon imaging has become an essential part of molecular imaging and nuclear medicine. Whether to establish a diagnosis or in the therapeutic monitoring, this modality presents performance that continues to improve. For over 50 years, several collimators have been proposed. Mainly governed by collimation parameters, the resolution-sensitivity trade-off is the factor determining the collimator the most suitable for an intended study. One alternative to the common approaches is the rotating slat collimator (RSC). In the present study, we are aiming at developing a preclinical system equipped with a RSC dedicated to mice and rats imaging, which requires both high sensitivity and spatial resolution. We investigated the resolution-sensitivity trade-offs obtained by varying different collimation parameters: (i) the slats height (H), and (ii) the gap between two consecutive slats (g), considering different intrinsic spatial resolutions. One system matrix was generated for each set of collimation parameters (H,g). Spatial resolutions, Signal-to-Noise Ratio (SNR) and sensitivity obtained for all the set of collimation parameters (H,g) were measured in the 2D projections reconstructed with ML-EM. According to our results, 20 mm high slats and a 1 mm gap were chosen as a good RSC candidate for a preclinical detection module. This collimator will ensure a sensitivity greater than 0.2% and a system spatial resolution below 1 mm, considering an intrinsic spatial resolution below 0.8 mm.

  5. Imaging MALDI mass spectrometry of sphingolipids using an oscillating capillary nebulizer matrix application system.

    Science.gov (United States)

    Chen, Yanfeng; Liu, Ying; Allegood, Jeremy; Wang, Elaine; Cachón-González, Begoña; Cox, Timothy M; Merrill, Alfred H; Sullards, M Cameron

    2010-01-01

    Matrix deposition is a critical step in tissue imaging by matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS). It greatly affects the quality of MALDI imaging, especially for the analytes (such as lipids) that may easily dissolve in the solvent used for the matrix application. This chapter describes the use of an oscillating capillary nebulizer (OCN) to spray small droplets of matrix aerosol onto the sample surface for improved matrix homogeneity, reduced crystal size, and controlled solvent effects. This protocol allows visualization of many different lipid species and, of particular interest, sphingolipids in tissue slices of Tay-Sachs/Sandhoff disease by imaging MALDI-MS. The structures of these lipids were identified by analysis of tissue extracts using electrospray ionization in conjunction with tandem mass spectrometry (MS/MS and MS(3)). These results illustrate the usefulness of tissue imaging MALDI-MS with matrix deposition by OCN for the molecular analysis in normal physiology and pathology. In addition, the observation of numerous lipid subclasses with distinct localizations in the brain slices demonstrates that imaging MALDI-MS could be effectively used for "lipidomic" studies. PMID:20680588

  6. An adaptive method with weight matrix as a function of the state to design the rotatory flexible system control law

    Science.gov (United States)

    Souza, Luiz C. G.; Bigot, P.

    2016-10-01

    One of the most well-known techniques of optimal control is the theory of Linear Quadratic Regulator (LQR). This method was originally applied only to linear systems but has been generalized for non-linear systems: the State Dependent Riccati Equation (SDRE) technique. One of the advantages of SDRE is that the weight matrix selection is the same as in LQR. The difference is that weights are not necessarily constant: they can be state dependent. Then, it gives an additional flexibility to design the control law. Many are applications of SDRE for simulation or real time control but generally SDRE weights are chosen constant so no advantage of this flexibility is taken. This work serves to show through simulation that state dependent weights matrix can improve SDRE control performance. The system is a non-linear flexible rotatory beam. In a brief first part SDRE theory will be explained and the non-linear model detailed. Then, influence of SDRE weight matrix associated with the state Q will be analyzed to get some insight in order to assume a state dependent law. Finally, these laws are tested and compared to constant weight matrix Q. Based on simulation results; one concludes showing the benefits of using an adaptive weight Q rather than a constant one.

  7. General A 9 × 9 Matrix Representation of Birman—Wenzl—Murakami Algebra and Berry Phase in Yang—Baxter System

    Science.gov (United States)

    Gou, Li-Dan; Xue, Kang; Wang, Gang-Cheng

    2011-02-01

    We present a 9 × 9 S-matrix and E-matrix. A representation of specialized Birman—Wenzl—Murakami algebra is obtained. Starting from the given braid group representation S-matrix, we obtain the trigonometric solution of Yang-Baxter equation. A unitary matrix Ř(x, ϕ1,ϕ2) is generated via the Yang—Baxterization approach. Then we construct a Yang—Baxter Hamiltonian through the unitary matrix Ř(x, ϕ1,ϕ2). Berry phase of this Yang—Baxter system is investigated in detail.

  8. Properties and mechanisms of drug release from matrix tablets containing poly(ethylene oxide) and poly(acrylic acid) as release retardants.

    Science.gov (United States)

    Zhang, Feng; Meng, Fan; Lubach, Joseph; Koleng, Joseph; Watson, N A

    2016-08-01

    The interactions between poly(ethylene oxide) (PEO) and poly(acrylic acid) (PAA) in aqueous medium at pH 6.8 were investigated in the current study. We have also studied the effect of interpolymer interactions and various formulation variables, including the molecular weight of PEO, the ratio between PEO and PAA, the crystallinity of PEO, and the presence of an acidifying agent, on the release of theophylline from matrix tablets containing both PEO and PAA as release retardants. At pH 6.8, the synergy in solution viscosity between PEO and PAA as the result of ion-dipole interaction was observed in this study. The release of theophylline from the matrix tablets containing physical mixtures of PEO and PAA was found to be a function of dissolution medium pH because of the pH-dependent interactions between these two polymers. Because of the formation of water insoluble interpolymer complex between PEO and PAA in aqueous medium at pH below 4.0, the release of theophylline was independent of PEO molecular weight and was controlled by Fickian diffusion mechanism in 0.01N hydrochloric acid solution. In comparison, the drug release was a function of PEO molecular weight and followed the anomalous transport mechanism in phosphate buffer pH 6.8. The presence of PAA exerted opposite effects on the release of theophylline in phosphate buffer pH 6.8. In one aspect, theophylline release was accelerated because the erosion of PAA was much faster than that of PEO at pH6.8. On the opposite aspect, theophylline release was slowed down because of the formation of insoluble complex inside the gel layer as the result of the acidic microenvironment induced by PAA, and the increase in the viscosity of the gel layer as the result of the synergy between PEO and PAA. These two opposite effects offset each other. As a result, the release of theophylline remained statistically the same even when 75% PEO in the formulation was replaced with PAA. In phosphate buffer pH 6.8, the release of

  9. Third generation capture system: precipitating amino acid solvent systems

    NARCIS (Netherlands)

    Sanchez Fernandez, E.; Misiak, K.; Ham, L. van der; Goetheer, E.L.V.

    2013-01-01

    This work summarises the results of the design of novel separation processes for CO2 removal from flue gas based on precipitating amino acid solvents. The processes here described (DECAB, DECAB Plus and pH-swing) use a combination of enhanced CO2 absorption (based on the Le Chatelier’s principle) an

  10. Linear matrix inequality-based nonlinear adaptive robust control with application to unmanned aircraft systems

    Science.gov (United States)

    Kun, David William

    Unmanned aircraft systems (UASs) are gaining popularity in civil and commercial applications as their lightweight on-board computers become more powerful and affordable, their power storage devices improve, and the Federal Aviation Administration addresses the legal and safety concerns of integrating UASs in the national airspace. Consequently, many researchers are pursuing novel methods to control UASs in order to improve their capabilities, dependability, and safety assurance. The nonlinear control approach is a common choice as it offers several benefits for these highly nonlinear aerospace systems (e.g., the quadrotor). First, the controller design is physically intuitive and is derived from well known dynamic equations. Second, the final control law is valid in a larger region of operation, including far from the equilibrium states. And third, the procedure is largely methodical, requiring less expertise with gain tuning, which can be arduous for a novice engineer. Considering these facts, this thesis proposes a nonlinear controller design method that combines the advantages of adaptive robust control (ARC) with the powerful design tools of linear matrix inequalities (LMI). The ARC-LMI controller is designed with a discontinuous projection-based adaptation law, and guarantees a prescribed transient and steady state tracking performance for uncertain systems in the presence of matched disturbances. The norm of the tracking error is bounded by a known function that depends on the controller design parameters in a known form. Furthermore, the LMI-based part of the controller ensures the stability of the system while overcoming polytopic uncertainties, and minimizes the control effort. This can reduce the number of parameters that require adaptation, and helps to avoid control input saturation. These desirable characteristics make the ARC-LMI control algorithm well suited for the quadrotor UAS, which may have unknown parameters and may encounter external

  11. 300 Area waste acid treatment system closure plan

    International Nuclear Information System (INIS)

    The Hanford Facility Dangerous Waste Permit Application is considered to be a single application organized into a General Information Portion (document number DOERL-91-28) and a Unit-Specific Portion. The scope of the Unit-Specific Portion includes closure plan documentation submitted for individual, treatment, storage, and/or disposal units undergoing closure, such as the 300 Area Waste Acid Treatment System. Documentation contained in the General Information Portion is broader in nature and could be used by multiple treatment, storage, and/or disposal units (e.g., the glossary provided in the General Information Portion). Whenever appropriate, 300 Area Waste Acid Treatment System documentation makes cross-reference to the General Information Portion, rather than duplicating text. This 300 Area Waste Acid Treatment System Closure Plan (Revision 2) includes a Hanford Facility Dangerous Waste Permit Application, Part A, Form 3. Information provided in this closure plan is current as of April 1999

  12. 300 Area waste acid treatment system closure plan

    Energy Technology Data Exchange (ETDEWEB)

    LUKE, S.N.

    1999-05-17

    The Hanford Facility Dangerous Waste Permit Application is considered to be a single application organized into a General Information Portion (document number DOERL-91-28) and a Unit-Specific Portion. The scope of the Unit-Specific Portion includes closure plan documentation submitted for individual, treatment, storage, and/or disposal units undergoing closure, such as the 300 Area Waste Acid Treatment System. Documentation contained in the General Information Portion is broader in nature and could be used by multiple treatment, storage, and/or disposal units (e.g., the glossary provided in the General Information Portion). Whenever appropriate, 300 Area Waste Acid Treatment System documentation makes cross-reference to the General Information Portion, rather than duplicating text. This 300 Area Waste Acid Treatment System Closure Plan (Revision 2) includes a Hanford Facility Dangerous Waste Permit Application, Part A, Form 3. Information provided in this closure plan is current as of April 1999.

  13. Bile acid nuclear receptor FXR and digestive system diseases

    Directory of Open Access Journals (Sweden)

    Lili Ding

    2015-03-01

    Full Text Available Bile acids (BAs are not only digestive surfactants but also important cell signaling molecules, which stimulate several signaling pathways to regulate some important biological processes. The bile-acid-activated nuclear receptor, farnesoid X receptor (FXR, plays a pivotal role in regulating bile acid, lipid and glucose homeostasis as well as in regulating the inflammatory responses, barrier function and prevention of bacterial translocation in the intestinal tract. As expected, FXR is involved in the pathophysiology of a wide range of diseases of gastrointestinal tract, including inflammatory bowel disease, colorectal cancer and type 2 diabetes. In this review, we discuss current knowledge of the roles of FXR in physiology of the digestive system and the related diseases. Better understanding of the roles of FXR in digestive system will accelerate the development of FXR ligands/modulators for the treatment of digestive system diseases.

  14. Enterprise-process: computer-based application for obtaining a process-organisation matrix during strategic information system planning

    Directory of Open Access Journals (Sweden)

    José Alirio Rondón

    2010-04-01

    Full Text Available A lot of material has been published about strategic information system planning (SISP methodologies. These methods are designed to help information system planners to integrate their strategies with organisational stra-tegies. Classic business system planning for strategical alignment (BSP/SA theory stands out because it provides information systems with a reactive role regarding an organisation’s objectives and strategy. BSP/SA has been described in terms of phases and the specific tasks within them. This work was aimed at presenting a computer-based application automating one of the most important tasks in BSP/SA methodology (process-organisation matrix. This matrix allows storing information about the levels of present responsibilities in positions and processes. Automating this task has facilitated students’ analysing the process-organisation matrix during SISP workshops forming part of the Systems Management course (Systems Engineering, Universidad Nacional de Colombia. Improved results have thus arisen from such workshops. The present work aims to motivate software development for supporting SISP tasks.

  15. Low Complexity Precoder and Receiver Design for Massive MIMO Systems: A Large System Analysis using Random Matrix Theory

    KAUST Repository

    Sifaou, Houssem

    2016-05-01

    Massive MIMO systems are shown to be a promising technology for next generations of wireless communication networks. The realization of the attractive merits promised by massive MIMO systems requires advanced linear precoding and receiving techniques in order to mitigate the interference in downlink and uplink transmissions. This work considers the precoder and receiver design in massive MIMO systems. We first consider the design of the linear precoder and receiver that maximize the minimum signal-to-interference-plus-noise ratio (SINR) subject to a given power constraint. The analysis is carried out under the asymptotic regime in which the number of the BS antennas and that of the users grow large with a bounded ratio. This allows us to leverage tools from random matrix theory in order to approximate the parameters of the optimal linear precoder and receiver by their deterministic approximations. Such a result is of valuable practical interest, as it provides a handier way to implement the optimal precoder and receiver. To reduce further the complexity, we propose to apply the truncated polynomial expansion (TPE) concept on a per-user basis to approximate the inverse of large matrices that appear on the expressions of the optimal linear transceivers. Using tools from random matrix theory, we determine deterministic approximations of the SINR and the transmit power in the asymptotic regime. Then, the optimal per-user weight coe cients that solve the max-min SINR problem are derived. The simulation results show that the proposed precoder and receiver provide very close to optimal performance while reducing signi cantly the computational complexity. As a second part of this work, the TPE technique in a per-user basis is applied to the optimal linear precoding that minimizes the transmit power while satisfying a set of target SINR constraints. Due to the emerging research eld of green cellular networks, such a problem is receiving increasing interest nowadays. Closed

  16. Homogeneous vs. heterogeneous nucleation in water-dicarboxylic acid systems

    Directory of Open Access Journals (Sweden)

    A. I. Hienola

    2008-10-01

    Full Text Available Binary heterogeneous nucleation of water-succinic/glutaric/malonic/adipic acid on nanometer-sized particles is investigated within the frame of classical heterogeneous nucleation theory. Homogeneous nucleation is also included for comparison. It is found that the nucleation probabilities depend on the contact angle and on the size of the seed particles. New thermodynamical properties, such as saturation vapor pressure, density and surface tension for all the dicarboxylic acid aqueous solutions are included in the calculations. While the new surface tension and density formulations do not bring any significant difference in the computed nucleation rate for homogeneous nucleation for succinic and glutaric acids, the use of the newly derived equations for the vapor pressure decrease the acid concentrations in gas phase with 3 orders of magnitude. According to our calculations, the binary heterogeneous nucleation of succinic acid-water and glutaric acid-water – although it requires a 3–4 orders of magnitude lower vapor concentrations than the homogeneous nucleation – cannot take place in atmospheric conditions. On the other hand binary homogeneous nucleation of adipic acid-water systems might be possible in conditions occuring in upper boundary layer. However, a more detailed characterization of the interaction between the surface and the molecules of the nucleating vapor should be considered in the future.

  17. Lead/acid batteries in systems to improve power quality

    Science.gov (United States)

    Taylor, P.; Butler, P.; Nerbun, W.

    Increasing dependence on computer technology is driving needs for extremely high-quality power to prevent loss of information, material, and workers' time that represent billions of dollars annually. This cost has motivated commercial and Federal research and development of energy storage systems that detect and respond to power-quality failures in milliseconds. Electrochemical batteries are among the storage media under investigation for these systems. Battery energy storage systems that employ either flooded lead/acid or valve-regulated lead/acid battery technologies are becoming commercially available to capture a share of this emerging market. Cooperative research and development between the US Department of Energy and private industry have led to installations of lead/acid-based battery energy storage systems to improve power quality at utility and industrial sites and commercial development of fully integrated, modular battery energy storage system products for power quality. One such system by AC Battery Corporation, called the PQ2000, is installed at a test site at Pacific Gas and Electric Company (San Ramon, CA, USA) and at a customer site at Oglethorpe Power Corporation (Tucker, GA, USA). The PQ2000 employs off-the-shelf power electronics in an integrated methodology to control the factors that affect the performance and service life of production-model, low-maintenance, flooded lead/acid batteries. This system, and other members of this first generation of lead/acid-based energy storage systems, will need to compete vigorously for a share of an expanding, yet very aggressive, power quality market.

  18. Preliminary systems-interaction results from the Digraph Matrix Analysis of the Watts Bar Nuclear Power Plant safety-injection systems

    Energy Technology Data Exchange (ETDEWEB)

    Sacks, I.J.; Ashmore, B.C.; Champney, J.M.; Alesso, H.P.

    1983-06-01

    This report provides preliminary results generated by a Digraph Matrix Analysis (DMA) for a Systems Interaction analysis performed on the Safety Injection System of the Tennessee Valley Authority Watts Bar Nuclear Power Plant. An overview of DMA is provided along with a brief description of the computer codes used in DMA.

  19. A software tool for teaching and training how to build and use matrixes in strategic information systems planning

    Directory of Open Access Journals (Sweden)

    Javier Andrés Arias Sanabria

    2010-10-01

    Full Text Available Strategic information systems planning (SISP allows an organisation to determine a portfolio of computer-based applications to help it achieve its business objectives. IBM’s business system planning for strategic alignment (BSP/SA is an important technique for developing a strategic plan for an entire company’s information resource. BSP/SA has been described in terms of stages and the specific tasks within them. Tasks are usually done manually and require some experience. This work was thus aimed at presenting a computer-based application that automates two of the most important tasks in BSP/SA methodology: process-organisation matrix (POM and processes-data classes–matrix (PDM. Special emphasis was placed on analysing, designing and implementing systems development life-cycle for developing the software. An important part of the analysis consisted of conducting a literature review and the semi-structured interviews with some experts in SISP. A special contribution of the present work is the design and implementation of statistical reports associated with each matrix. Automating this task has facilitated students being able to analyse POM and PDM during SISP workshops forming part of the Information Systems Management course (Systems Engineering, Universidad Nacional de Colombia. Results arising from the workshops have also been improved.

  20. Study of self assembly system formed by malic acid and alkyloxy benzoic acids

    Energy Technology Data Exchange (ETDEWEB)

    Vijakumar, Vellalapalayam Nallagounder; Madhu Mohan, Mathukumalli Lakshmi Narayana [Bannari Amman Inst. of Technology, Sathyamangalam (IN). Liquid Crystal Research Lab. (LCRL)

    2010-12-15

    Self assembly systems formed by malic acid and alkyloxy benzoic acids are characterized. The ferroelectric ingredient malic acid formed double hydrogen bond with p-n-alkyloxy benzoic acids. Various hydrogen bonded complexes have been synthesized with malic acid and pentyl to dodecyloxy benzoic acid, respectively. Fourier transformation infrared (FTIR) studies confirm the hydrogen bond formation. Polarizing optical microscopic (POM) studies revealed the textural information while the transition and enthalpy values are calculated from differential scanning calorimetry (DSC) studies. A phase diagram has been constructed from the POMand DSC studies. Anew smectic ordering, smectic X*, has been identified which exhibits a finger print type texture. This phase has been characterized by POM, DSC, helix, and tilt angle studies. The transition from traditional cholesteric to smectic X{sup *} phase is observed to be first order. The tilt angle data in this phase has been fitted to a power law and the temperature variation of the tilt angle follows mean field theory predictions. The results of FTIR, POM, DSC, tilt angle, and helicoidal studies are discussed. (orig.)

  1. Thermodynamic properties of citric acid and the system citric acid-water

    NARCIS (Netherlands)

    Kruif, C.G. de; Miltenburg, J.C. van; Sprenkels, A.J.J.; Stevens, G.; Graaf, W. de; Wit, H.G.M. de

    1982-01-01

    The binary system citric acid-water has been investigated with static vapour pressure measurements, adiabatic calorimetry, solution calorimetry, solubility measurements and powder X-ray measurements. The data are correlated by thermodynamics and a large part of the phase diagram is given. Molar heat

  2. Integrity of Narrow Epithelial Tubes in the C. elegans Excretory System Requires a Transient Luminal Matrix

    Science.gov (United States)

    Ayala-Figueroa, Jesus; Parry, Jean M.; Pu, Pu; Hall, David H.

    2016-01-01

    Most epithelial cells secrete a glycoprotein-rich apical extracellular matrix that can have diverse but still poorly understood roles in development and physiology. Zona Pellucida (ZP) domain glycoproteins are common constituents of these matrices, and their loss in humans is associated with a number of diseases. Understanding of the functions, organization and regulation of apical matrices has been hampered by difficulties in imaging them both in vivo and ex vivo. We identified the PAN-Apple, mucin and ZP domain glycoprotein LET-653 as an early and transient apical matrix component that shapes developing epithelia in C. elegans. LET-653 has modest effects on shaping of the vulva and epidermis, but is essential to prevent lumen fragmentation in the very narrow, unicellular excretory duct tube. We were able to image the transient LET-653 matrix by both live confocal imaging and transmission electron microscopy. Structure/function and fluorescence recovery after photobleaching studies revealed that LET-653 exists in two separate luminal matrix pools, a loose fibrillar matrix in the central core of the lumen, to which it binds dynamically via its PAN domains, and an apical-membrane-associated matrix, to which it binds stably via its ZP domain. The PAN domains are both necessary and sufficient to confer a cyclic pattern of duct lumen localization that precedes each molt, while the ZP domain is required for lumen integrity. Ectopic expression of full-length LET-653, but not the PAN domains alone, could expand lumen diameter in the developing gut tube, where LET-653 is not normally expressed. Together, these data support a model in which the PAN domains regulate the ability of the LET-653 ZP domain to interact with other factors at the apical membrane, and this ZP domain interaction promotes expansion and maintenance of lumen diameter. These data identify a transient apical matrix component present prior to cuticle secretion in C. elegans, demonstrate critical roles for

  3. Random matrix models for decoherence and fidelity decay in quantum information systems

    Science.gov (United States)

    Pineda, Carlos; Seligman, Thomas H.

    2008-03-01

    This course aims to introduce the student to random matrix models for decoherence and fidelity decay. They present a very powerful alternate approach, that emphasizes the disordered character of many environments and uncontrollable perturbations/couplings. The inherent integrability of such models makes analytic studies possible. We limit our considerations to linear response treatment, as high fidelity and small decoherence are the backbone of quantum information processes. For fidelity decay, where experimental results are available, a comparison with experiments shows excellent agreement with random matrix theory predictions.

  4. Integrity of Narrow Epithelial Tubes in the C. elegans Excretory System Requires a Transient Luminal Matrix.

    Science.gov (United States)

    Gill, Hasreet K; Cohen, Jennifer D; Ayala-Figueroa, Jesus; Forman-Rubinsky, Rachel; Poggioli, Corey; Bickard, Kevin; Parry, Jean M; Pu, Pu; Hall, David H; Sundaram, Meera V

    2016-08-01

    Most epithelial cells secrete a glycoprotein-rich apical extracellular matrix that can have diverse but still poorly understood roles in development and physiology. Zona Pellucida (ZP) domain glycoproteins are common constituents of these matrices, and their loss in humans is associated with a number of diseases. Understanding of the functions, organization and regulation of apical matrices has been hampered by difficulties in imaging them both in vivo and ex vivo. We identified the PAN-Apple, mucin and ZP domain glycoprotein LET-653 as an early and transient apical matrix component that shapes developing epithelia in C. elegans. LET-653 has modest effects on shaping of the vulva and epidermis, but is essential to prevent lumen fragmentation in the very narrow, unicellular excretory duct tube. We were able to image the transient LET-653 matrix by both live confocal imaging and transmission electron microscopy. Structure/function and fluorescence recovery after photobleaching studies revealed that LET-653 exists in two separate luminal matrix pools, a loose fibrillar matrix in the central core of the lumen, to which it binds dynamically via its PAN domains, and an apical-membrane-associated matrix, to which it binds stably via its ZP domain. The PAN domains are both necessary and sufficient to confer a cyclic pattern of duct lumen localization that precedes each molt, while the ZP domain is required for lumen integrity. Ectopic expression of full-length LET-653, but not the PAN domains alone, could expand lumen diameter in the developing gut tube, where LET-653 is not normally expressed. Together, these data support a model in which the PAN domains regulate the ability of the LET-653 ZP domain to interact with other factors at the apical membrane, and this ZP domain interaction promotes expansion and maintenance of lumen diameter. These data identify a transient apical matrix component present prior to cuticle secretion in C. elegans, demonstrate critical roles for

  5. High Level Waste System Impacts from Acid Dissolution of Sludge

    Energy Technology Data Exchange (ETDEWEB)

    KETUSKY, EDWARD

    2006-04-20

    This research evaluates the ability of OLI{copyright} equilibrium based software to forecast Savannah River Site High Level Waste system impacts from oxalic acid dissolution of Tank 1-15 sludge heels. Without further laboratory and field testing, only the use of oxalic acid can be considered plausible to support sludge heel dissolution on multiple tanks. Using OLI{copyright} and available test results, a dissolution model is constructed and validated. Material and energy balances, coupled with the model, identify potential safety concerns. Overpressurization and overheating are shown to be unlikely. Corrosion induced hydrogen could, however, overwhelm the tank ventilation. While pH adjustment can restore the minimal hydrogen generation, resultant precipitates will notably increase the sludge volume. OLI{copyright} is used to develop a flowsheet such that additional sludge vitrification canisters and other negative system impacts are minimized. Sensitivity analyses are used to assess the processability impacts from variations in the sludge/quantities of acids.

  6. Skin delivery of ferulic acid from different vesicular systems.

    Science.gov (United States)

    Chen, Ming; Liu, Xiangli; Fahr, Alfred

    2010-10-01

    The aim of the present research is to evaluate the skin delivery capabilities of different vesicular systems, including conventional liposomes (CL), Tween 80-based deformable liposomes (DL), invasomes (INS) and ethosomes bearing ferulic acid (FA) being an antioxidant exhibiting a wide range of therapeutic effects against various diseases. All of the test formulations were characterized for particle size distribution, zeta-potential, vesicular shape and surface morphology, in vitro human skin permeation and skin deposition. Dynamic Light Scattering (DLS) and Transmission Electron Microscopy (TEM) defined that all of liposomal vesicles were almost spherical, displaying unilamellar structures with low polydispersity (PDI ethosomal system containing 18.0 mg/ml of ferulic acid with an significantly (P ethosomes are promising vesicular carriers for delivering ferulic acid into or across the skin. PMID:21329050

  7. Data and Knowledge Base on the Basis of the Expanded Matrix Model of Their Representation for the Intelligent System of Road-Climatic Zoning of Territories

    Science.gov (United States)

    Yankovskaya, A.; Cherepanov, D.; Selivanikova, O.

    2016-08-01

    An extended matrix model of data and knowledge representation on the investigated area, as well as a matrix model of data representation on the territory under investigation, are proposed for the intelligent system of road-climatic zoning of territories (RCZT) - the main information technology of RCZT. A part of the West Siberian region has been selected as the investigated territory. The extended matrix model of knowledge representation is filled out by knowledge engineers with participation of highly qualified experts in the field of RCZT. The matrix model of data representation on the territory under investigation is filled out by persons concerned in RCZT of the motor-roads management system.

  8. 21 CFR 862.3580 - Lysergic acid diethylamide (LSD) test system.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Lysergic acid diethylamide (LSD) test system. 862... Test Systems § 862.3580 Lysergic acid diethylamide (LSD) test system. (a) Identification. A lysergic acid diethylamide (LSD) test system is a device intended to measure lysergic acid diethylamide,...

  9. Analytical, experimental, and Monte Carlo system response matrix for pinhole SPECT reconstruction

    Energy Technology Data Exchange (ETDEWEB)

    Aguiar, Pablo, E-mail: pablo.aguiar.fernandez@sergas.es [Fundación Ramón Domínguez, Medicina Nuclear, CHUS, Spain and Grupo de Imaxe Molecular, IDIS, Santiago de Compostela 15706 (Spain); Pino, Francisco [Unitat de Biofísica, Facultat de Medicina, Universitat de Barcelona, Spain and Servei de Física Médica i Protecció Radiológica, Institut Catalá d' Oncologia, Barcelona 08036 (Spain); Silva-Rodríguez, Jesús [Fundación Ramón Domínguez, Medicina Nuclear, CHUS, Santiago de Compostela 15706 (Spain); Pavía, Javier [Servei de Medicina Nuclear, Hospital Clínic, Barcelona (Spain); Institut d' Investigacions Biomèdiques August Pí i Sunyer (IDIBAPS) (Spain); CIBER en Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), Barcelona 08036 (Spain); Ros, Doménec [Unitat de Biofísica, Facultat de Medicina, Casanova 143 (Spain); Institut d' Investigacions Biomèdiques August Pí i Sunyer (IDIBAPS) (Spain); CIBER en Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), Barcelona 08036 (Spain); Ruibal, Álvaro [Servicio Medicina Nuclear, CHUS (Spain); Grupo de Imaxe Molecular, Facultade de Medicina (USC), IDIS, Santiago de Compostela 15706 (Spain); Fundación Tejerina, Madrid (Spain); and others

    2014-03-15

    Purpose: To assess the performance of two approaches to the system response matrix (SRM) calculation in pinhole single photon emission computed tomography (SPECT) reconstruction. Methods: Evaluation was performed using experimental data from a low magnification pinhole SPECT system that consisted of a rotating flat detector with a monolithic scintillator crystal. The SRM was computed following two approaches, which were based on Monte Carlo simulations (MC-SRM) and analytical techniques in combination with an experimental characterization (AE-SRM). The spatial response of the system, obtained by using the two approaches, was compared with experimental data. The effect of the MC-SRM and AE-SRM approaches on the reconstructed image was assessed in terms of image contrast, signal-to-noise ratio, image quality, and spatial resolution. To this end, acquisitions were carried out using a hot cylinder phantom (consisting of five fillable rods with diameters of 5, 4, 3, 2, and 1 mm and a uniform cylindrical chamber) and a custom-made Derenzo phantom, with center-to-center distances between adjacent rods of 1.5, 2.0, and 3.0 mm. Results: Good agreement was found for the spatial response of the system between measured data and results derived from MC-SRM and AE-SRM. Only minor differences for point sources at distances smaller than the radius of rotation and large incidence angles were found. Assessment of the effect on the reconstructed image showed a similar contrast for both approaches, with values higher than 0.9 for rod diameters greater than 1 mm and higher than 0.8 for rod diameter of 1 mm. The comparison in terms of image quality showed that all rods in the different sections of a custom-made Derenzo phantom could be distinguished. The spatial resolution (FWHM) was 0.7 mm at iteration 100 using both approaches. The SNR was lower for reconstructed images using MC-SRM than for those reconstructed using AE-SRM, indicating that AE-SRM deals better with the

  10. Evidence of heterosynaptic LTD in the human nociceptive system: superficial skin neuromodulation using a matrix electrode reduces deep pain sensitivity.

    Directory of Open Access Journals (Sweden)

    Martin Mücke

    Full Text Available Long term depression (LTD is a neuronal learning mechanism after low frequency stimulation (LFS. This study compares two types of electrodes (concentric vs. matrix and stimulation frequencies (4 and 30 Hz to examine homo- and heterosynaptic effects indirectly depicted from the somatosensory profile of healthy subjects. Both electrodes were compared in a prospective, randomized, controlled cross-over study using 4 Hz as the conditioning LFS compared to 30 Hz (intended sham condition. Quantitative sensory testing (QST was used to examine 13 thermal and mechanical detection and pain thresholds. Sixteen healthy volunteers (10 women, age 31.0 ± 12.7 years were examined. Depending on the electrodes and frequencies used a divergent pattern of sensory minus signs occurred. Using LFS the concentric electrode increased thermal thresholds, while the matrix electrode rather increased mechanical including deep pain thresholds. Findings after cutaneous neuromodulation using LFS and a matrix electrode are consistent with the concept of heterosynaptic LTD in the human nociceptive system, where deep pain sensitivity was reduced after superficial stimulation of intraepidermal nerve fibres. Cutaneous neuromodulation using LFS and a matrix electrode may be a useful tool to influence deep pain sensitivity in a variety of chronic pain syndromes.

  11. Complete polarization characterization of single plasmonic nanoparticle enabled by a novel Dark-field Mueller matrix spectroscopy system

    CERN Document Server

    Chandel, Shubham; Ray, Subir K; Das, Anwesh; Ghosh, Anirudha; Raj, Satyabrata; Ghosh, Nirmalya

    2015-01-01

    Information on the polarization properties of scattered light from plasmonic systems are of paramount importance due to fundamental interest and potential applications. However, such studies are severely compromised due to the experimental difficulties in recording full polarization response of plasmonic nanostructures. Here, we report on a novel Mueller matrix spectroscopic system capable of acquiring complete polarization information from single isolated plasmonic nanoparticle/nanostructure. The outstanding issues pertaining to reliable measurements of full 4X4 spectroscopic scattering Mueller matrices from single nanoparticle/nanostructures are overcome by integrating an efficient Mueller matrix measurement scheme and a robust calibration method with a dark-field microscopic spectroscopy arrangement.The spectral polarization responses of the required polarization state generator, analyzer units, the imaging and the detection systemsare taken care off by eigenvalue calibration, thus enabling recording of th...

  12. On absolute stability of Lur'e control systems with multiple non-linearities using linear matrix inequalities

    Institute of Scientific and Technical Information of China (English)

    Min WU; Yong HE; Jinhua SHE

    2004-01-01

    Necessary and suffcient conditions for the existence of a Lyapunov function in the Lur'e form to guarantee the absolute stability ofLur' e control systems with multiple non-linearities are discussed in this paper. It simplifies the existence problem to one of solving a set of linear matrix inequalities (LMIs). If those LMIs are feasible, free parameters in the Lyapunov function,such as the positive definite matrix and the coefficients of the integral terms, are given by the solution of the LMIs. Otherwise, this Lyapunov function does not exist. Some sufficient conditions are also obtained for the robust absolute stability of uncertain systems.A numerical example is provided to demonstrate the effectiveness of the proposed method.

  13. Aqueous flow and transport in analog systems of fractures embedded in permeable matrix

    DEFF Research Database (Denmark)

    Sonnenborg, Torben Obel; Butts, Michael Brian; Jensen, Karsten Høgh

    1999-01-01

    Two-dimensional laboratory investigations of flow and transport in a fractured permeable medium are presented. Matrix blocks of a manufactured consolidated permeable medium were arranged together to create fractures in the spaces between the blocks. Experiments examined flow and transport in four...

  14. Effect of fatty acids and programming on the immune system

    OpenAIRE

    Fear, Alison Lindsay

    2010-01-01

    Research to date has suggested that fatty acids (FAs) may affect the immune system, through their (and those of their metabolites) effects on membranes, mediators, and gene expression. However, despite the research carried out, there still exist gaps of knowledge where further research is required. In addition, programming by diet in pregnancy may affect the immune system, due to stress and/or structural and functional changes to immune cells, but whether this effect is long-lasting is uncert...

  15. Inducible gene expression system by 3-hydroxypropionic acid

    OpenAIRE

    Zhou, Shengfang; Ainala, Satish Kumar; Seol, Eunhee; Nguyen, Trinh Thi; Park, Sunghoon

    2015-01-01

    Background 3-Hydroxypropionic acid (3-HP) is an important platform chemical that boasts a variety of industrial applications. Gene expression systems inducible by 3-HP, if available, are of great utility for optimization of the pathways of 3-HP production and excretion. Results Here we report the presence of unique inducible gene expression systems in Pseudomonas denitrificans and other microorganisms. In P. denitrificans, transcription of three genes (hpdH, mmsA and hbdH-4) involved in 3-HP ...

  16. Nonlinear optical studies on 4-(ferrocenylmethylimino)-2-hydroxy-benzoic acid thin films deposited by matrix-assisted pulsed laser evaporation (MAPLE)

    Science.gov (United States)

    Matei, Andreea; Marinescu, Maria; Constantinescu, Catalin; Ion, Valentin; Mitu, Bogdana; Ionita, Iulian; Dinescu, Maria; Emandi, Ana

    2016-06-01

    We present results on a new, laboratory synthesized ferrocene-derivative, i.e. 4-(ferrocenylmethylimino)-2-hydroxy-benzoic acid. Thin films with controlled thickness are deposited by matrix-assisted pulsed laser evaporation (MAPLE), on quartz and silicon substrates, with the aim of evaluating the nonlinear optical properties for potential optoelectronic applications. Dimethyl sulfoxide was used as matrix, with 1% wt. concentration of the guest compound. The frozen target is irradiated by using a Nd:YAG laser (4ω/266 nm, 7 ns pulse duration, 10 Hz repetition rate), at low fluences ranging from 0.1 to 1 J/cm2. Atomic force microscopy (AFM) and scanning electron microscopy (SEM) are used to probe the surface morphology of the films. Fourier transform infrared (FTIR) and Raman spectroscopy reveal similar structure of the thin film material when compared to the starting material. The optical properties of the thin films are investigated by spectroscopic-ellipsometry (SE), and the refractive index dependence with respect to temperature is studied. The second harmonic generation (SHG) potential is assessed by using a femtosecond Ti:sapphire laser (800 nm, 60-100 fs pulse duration, 80 MHz repetition rate), at 200 mW maximum output power, revealing that the SHG signal intensity is strongly influenced by the films' thickness.

  17. Constructing a database for economic modelling from the System of National Accounts: a Social Accounting Matrix for Portugal

    OpenAIRE

    Santos, Susana

    2006-01-01

    Based on the country's National Accounts, an aggregate Social Accounting Matrix (SAM) will be constructed for the Portuguese economy. The full consonance between the two will be demonstrated by identifying both the items and balances of the various internal accounts of the System of National Accounts in the constructed SAM. The balance of the government budget and the balance of payments will also be identified. Blocks of sub-matrices with common characteristics will be identified and describ...

  18. Thermodynamics of sodium dodecyl sulphate-salicylic acid based micellar systems and their potential use in fruits postharvest.

    Science.gov (United States)

    Cid, A; Morales, J; Mejuto, J C; Briz-Cid, N; Rial-Otero, R; Simal-Gándara, J

    2014-05-15

    Micellar systems have excellent food applications due to their capability to solubilise a large range of hydrophilic and hydrophobic substances. In this work, the mixed micelle formation between the ionic surfactant sodium dodecyl sulphate (SDS) and the phenolic acid salicylic acid have been studied at several temperatures in aqueous solution. The critical micelle concentration and the micellization degree were determined by conductometric techniques and the experimental data used to calculate several useful thermodynamic parameters, like standard free energy, enthalpy and entropy of micelle formation. Salicylic acid helps the micellization of SDS, both by increasing the additive concentration at a constant temperature and by increasing temperature at a constant concentration of additive. The formation of micelles of SDS in the presence of salicylic acid was a thermodynamically spontaneous process, and is also entropically controlled. Salicylic acid plays the role of a stabilizer, and gives a pathway to control the three-dimensional water matrix structure. The driving force of the micellization process is provided by the hydrophobic interactions. The isostructural temperature was found to be 307.5 K for the mixed micellar system. This article explores the use of SDS-salicylic acid based micellar systems for their potential use in fruits postharvest.

  19. Parallelism in matrix computations

    CERN Document Server

    Gallopoulos, Efstratios; Sameh, Ahmed H

    2016-01-01

    This book is primarily intended as a research monograph that could also be used in graduate courses for the design of parallel algorithms in matrix computations. It assumes general but not extensive knowledge of numerical linear algebra, parallel architectures, and parallel programming paradigms. The book consists of four parts: (I) Basics; (II) Dense and Special Matrix Computations; (III) Sparse Matrix Computations; and (IV) Matrix functions and characteristics. Part I deals with parallel programming paradigms and fundamental kernels, including reordering schemes for sparse matrices. Part II is devoted to dense matrix computations such as parallel algorithms for solving linear systems, linear least squares, the symmetric algebraic eigenvalue problem, and the singular-value decomposition. It also deals with the development of parallel algorithms for special linear systems such as banded ,Vandermonde ,Toeplitz ,and block Toeplitz systems. Part III addresses sparse matrix computations: (a) the development of pa...

  20. [Modern polymers in matrix tablets technology].

    Science.gov (United States)

    Zimmer, Łukasz; Kasperek, Regina; Poleszak, Ewa

    2014-01-01

    Matrix tablets are the most popular method of oral drug administration, and polymeric materials have been used broadly in matrix formulations to modify and modulate drug release rate. The main goal of the system is to extend drug release profiles to maintain a constant in vivo plasma drug concentration and a consistent pharmacological effect. Polymeric matrix tablets offer a great potential as oral controlled drug delivery systems. Cellulose derivatives, like hydroxypropyl methylcellulose (HPMC) are often used as matrix formers. However, also other types of polymers can be used for this purpose including: Kollidon SR, acrylic acid polymers such as Eudragits and Carbopols. Nevertheless, polymers of natural origin like: carragens, chitosan and alginates widely used in the food and cosmetics industry are now coming to the fore of pharmaceutical research and are used in matrix tablets technology. Modern polymers allow to obtain matrix tablets by 3D printing, which enables to develop new formulation types. In this paper, the polymers used in matrix tablets technology and examples of their applications were described. PMID:25739125

  1. [Modern polymers in matrix tablets technology].

    Science.gov (United States)

    Zimmer, Łukasz; Kasperek, Regina; Poleszak, Ewa

    2014-01-01

    Matrix tablets are the most popular method of oral drug administration, and polymeric materials have been used broadly in matrix formulations to modify and modulate drug release rate. The main goal of the system is to extend drug release profiles to maintain a constant in vivo plasma drug concentration and a consistent pharmacological effect. Polymeric matrix tablets offer a great potential as oral controlled drug delivery systems. Cellulose derivatives, like hydroxypropyl methylcellulose (HPMC) are often used as matrix formers. However, also other types of polymers can be used for this purpose including: Kollidon SR, acrylic acid polymers such as Eudragits and Carbopols. Nevertheless, polymers of natural origin like: carragens, chitosan and alginates widely used in the food and cosmetics industry are now coming to the fore of pharmaceutical research and are used in matrix tablets technology. Modern polymers allow to obtain matrix tablets by 3D printing, which enables to develop new formulation types. In this paper, the polymers used in matrix tablets technology and examples of their applications were described.

  2. Cloud point extraction of plutonium in environmental matrixes coupled to ICPMS and α spectrometry in highly acidic conditions.

    Science.gov (United States)

    Labrecque, Charles; Whitty-Léveillé, Laurence; Larivière, Dominic

    2013-11-01

    A new cloud point extraction procedure has been developed for the quantification of plutonium(IV) in environmental samples. The separation procedure can be either coupled to inductively coupled plasma mass spectrometry (ICPMS) or α spectrometry for plutonium quantification. The method uses a combination of selective ligand (P,P'-di(2-ethylhexyl) methanediphosphonic acid (H2DEH[MDP])) and micelle shielding by bromine formation to enable quantitative extraction of Pu in highly acidic solutions. Cross-optimization of all parameters (nonionic and ionic surfactant, chelating agent, bromate, bromide, and pH) led to optimal of the extraction conditions. Figures of merit of the method for the detection using α spectrometry and ICPMS are reported (limit of detection, limit of quantification, minimal detectable activity, and recovery). Quantitative extractions (>95%) were obtained for a wide variety of aqueous and digested samples (synthetic urine, wastewater, drinking water, seawater, and soil samples). The method features the first successful coupling between α spectrometry and cloud point extraction and is the first demonstration of CPE suitability with metaborate fusion as a sample preparation approach, techniques used extensively in nuclear industries.

  3. Initial guidance on digraph-matrix analysis for systems interaction studies at selected LWR's

    Energy Technology Data Exchange (ETDEWEB)

    Alesso, H.P.; Sacks, I.J.; Smith, C.F.

    1982-08-12

    The Nuclear Regulatory Commission (NRC) is currently developing guidance to search for and evaluate systems interactions at light water reactors (LWRs). In addition, related efforts are being made to incorporate such analyses into the framework of Probabilistic Risk Assessment (PRA). Preliminary results indicate that there are at least three concepts on how systems interactions can be analyzed independently or incorporated into an overall PRA. One point of view is that systems interactions can be adequately analyzed by enhancing existing PRAs. A second and closely related point of view is that systems interactions can be incorporated into a PRA in the event-tree stage of analysis. This approach attempts to capture systems interactions at an earlier stage of analysis. By treating dependencies in the event tree analysis portion of a PRA, the requirement of fault tree modeling at additional levels of detail is reduced. A third point of view about the Systems Interaction problem is that a new technique, called Digraph-Matrix Analysis (DMA), which utilizes matrix representation of logic diagrams, may offer a more complete and possibly more efficient analysis in certain areas. This report will present proposed initial guidance on DMA for application to systems interactions. DMA will be presented as a procedure independent from PRA. Peer review and later sample applications can provide useful feedback for refining the final guidance.

  4. Deregulation of the lysyl hydroxylase matrix cross-linking system in experimental and clinical bronchopulmonary dysplasia

    OpenAIRE

    Witsch, Thilo J.; Turowski, Paweł; Sakkas, Elpidoforos; Niess, Gero; Becker, Simone; Herold, Susanne; Mayer, Konstantin; Vadász, István; Roberts, Jesse D.; Seeger, Werner; Morty, Rory E.

    2013-01-01

    Bronchopulmonary dysplasia (BPD) is a common and serious complication of premature birth, characterized by a pronounced arrest of alveolar development. The underlying pathophysiological mechanisms are poorly understood although perturbations to the maturation and remodeling of the extracellular matrix (ECM) are emerging as candidate disease pathomechanisms. In this study, the expression and regulation of three members of the lysyl hydroxylase family of ECM remodeling enzymes (Plod1, Plod2, an...

  5. Analysis of innovative matrix systems for continuous fiber reinforced plastics in RTM process

    OpenAIRE

    Bosch Herrero, Mariona

    2012-01-01

    The use of lightweight and high-performance materials is nowadays one of the main challenge for the global automotive industry. Companies are forced to look for new ways to design and manufacture a commercially viable lightweight vehicle in order to meet stringent carbon emissions targets and offer highly fuel efficient vehicles to the consumer while maintaining structural performance. The use of polymer matrix composites in substitution of the present metal components remains a top priority....

  6. Tissue matrix arrays for high-throughput screening and systems analysis of cell function.

    Science.gov (United States)

    Beachley, Vince Z; Wolf, Matthew T; Sadtler, Kaitlyn; Manda, Srikanth S; Jacobs, Heather; Blatchley, Michael R; Bader, Joel S; Pandey, Akhilesh; Pardoll, Drew; Elisseeff, Jennifer H

    2015-12-01

    Cell and protein arrays have demonstrated remarkable utility in the high-throughput evaluation of biological responses; however, they lack the complexity of native tissue and organs. Here we spotted tissue extracellular matrix (ECM) particles as two-dimensional (2D) arrays or incorporated them with cells to generate three-dimensional (3D) cell-matrix microtissue arrays. We then investigated the responses of human stem, cancer and immune cells to tissue ECM arrays originating from 11 different tissues. We validated the 2D and 3D arrays as representative of the in vivo microenvironment by means of quantitative analysis of tissue-specific cellular responses, including matrix production, adhesion and proliferation, and morphological changes after culture. The biological outputs correlated with tissue proteomics, and network analysis identified several proteins linked to cell function. Our methodology enables broad screening of ECMs to connect tissue-specific composition with biological activity, providing a new resource for biomaterials research and further understanding of regeneration and disease mechanisms. PMID:26480475

  7. Hyaluronic acid fillers with cohesive polydensified matrix for soft-tissue augmentation and rejuvenation: a literature review

    Science.gov (United States)

    Prasetyo, Adri D; Prager, Welf; Rubin, Mark G; Moretti, Ernesto A; Nikolis, Andreas

    2016-01-01

    Background Cohesive monophasic polydensified fillers show unique viscoelastic properties and variable density of hyaluronic acid, allowing for a homogeneous tissue integration and distribution of the material. Objective The aim of this paper was to review the clinical data regarding the performance, tolerability, and safety of the Belotero® fillers for soft-tissue augmentation and rejuvenation. Methods A literature search was performed up until May 31, 2015 to identify all relevant articles on Belotero® fillers (Basic/Balance, Hydro, Soft, Intense, Volume) and equivalent products (Esthélis®, Mesolis®, Fortélis®, Modélis®). Results This comprehensive review included 26 papers. Findings from three randomized controlled trials showed a greater reduction in nasolabial fold severity with Belotero® Basic/Balance than with collagen (at 8, 12, 16, and 24 weeks, n=118) and Restylane® (at 4 weeks, n=40), and higher patient satisfaction with Belotero® Intense than with Perlane® (at 2 weeks, n=20). With Belotero® Basic/Balance, an improvement of at least 1 point on the severity scale can be expected in ~80% of patients 1–6 months after injection, with an effect still visible at 8–12 months. Positive findings were also reported with Belotero® Volume (no reduction in hyaluronic acid volume at 12 months, as demonstrated by magnetic resonance imaging), Soft (improvement in the esthetic outcomes when used in a sequential approach), and Hydro (improvement in skin appearance in all patients). The most common adverse effects were mild-to-moderate erythema, edema, and hematoma, most of which were temporary. There were no reports of Tyndall effect, nodules, granulomas, or tissue necrosis. Conclusion Clinical evidence indicates sustainable esthetic effects, good safety profile, and long-term tolerability of the Belotero® fillers, particularly Belotero® Basic/Balance and Intense. PMID:27660479

  8. Hyaluronic acid fillers with cohesive polydensified matrix for soft-tissue augmentation and rejuvenation: a literature review

    Science.gov (United States)

    Prasetyo, Adri D; Prager, Welf; Rubin, Mark G; Moretti, Ernesto A; Nikolis, Andreas

    2016-01-01

    Background Cohesive monophasic polydensified fillers show unique viscoelastic properties and variable density of hyaluronic acid, allowing for a homogeneous tissue integration and distribution of the material. Objective The aim of this paper was to review the clinical data regarding the performance, tolerability, and safety of the Belotero® fillers for soft-tissue augmentation and rejuvenation. Methods A literature search was performed up until May 31, 2015 to identify all relevant articles on Belotero® fillers (Basic/Balance, Hydro, Soft, Intense, Volume) and equivalent products (Esthélis®, Mesolis®, Fortélis®, Modélis®). Results This comprehensive review included 26 papers. Findings from three randomized controlled trials showed a greater reduction in nasolabial fold severity with Belotero® Basic/Balance than with collagen (at 8, 12, 16, and 24 weeks, n=118) and Restylane® (at 4 weeks, n=40), and higher patient satisfaction with Belotero® Intense than with Perlane® (at 2 weeks, n=20). With Belotero® Basic/Balance, an improvement of at least 1 point on the severity scale can be expected in ~80% of patients 1–6 months after injection, with an effect still visible at 8–12 months. Positive findings were also reported with Belotero® Volume (no reduction in hyaluronic acid volume at 12 months, as demonstrated by magnetic resonance imaging), Soft (improvement in the esthetic outcomes when used in a sequential approach), and Hydro (improvement in skin appearance in all patients). The most common adverse effects were mild-to-moderate erythema, edema, and hematoma, most of which were temporary. There were no reports of Tyndall effect, nodules, granulomas, or tissue necrosis. Conclusion Clinical evidence indicates sustainable esthetic effects, good safety profile, and long-term tolerability of the Belotero® fillers, particularly Belotero® Basic/Balance and Intense.

  9. Fully 3D tomographic reconstruction by Monte Carlo simulation of the system matrix in preclinical PET with iodine 124

    International Nuclear Information System (INIS)

    Immuno-PET imaging can be used to assess the pharmacokinetic in radioimmunotherapy. When using iodine-124, PET quantitative imaging is limited by physics-based degrading factors within the detection system and the object, such as the long positron range in water and the complex spectrum of gamma photons. The objective of this thesis was to develop a fully 3D tomographic reconstruction method (S(MC)2PET) using Monte Carlo simulations for estimating the system matrix, in the context of preclinical imaging with iodine-124. The Monte Carlo simulation platform GATE was used for that respect. Several complexities of system matrices were calculated, with at least a model of the PET system response function. Physics processes in the object was either neglected or taken into account using a precise or a simplified object description. The impact of modelling refinement and statistical variance related to the system matrix elements was evaluated on final reconstructed images. These studies showed that a high level of complexity did not always improve qualitative and quantitative results, owing to the high-variance of the associated system matrices. (author)

  10. Improving thermal stability and light fastness of Acid Red 114 by incorporating its anions in a ZnAl-layered double hydroxides matrix

    Institute of Scientific and Technical Information of China (English)

    Haifeng Zhu; Liren Wang; Pinggui Tang; Yongjun Feng; Dianqing Li

    2012-01-01

    Incorporation of anions of Acid Red 114 dye (1,3-naphthalenedisulfonic acid,8-[2-[3,3'-dimethyl-4'-[2-[4-[[(4-methylphenyl)sulfonyl]oxy] phenyl]diazenyl] [1,1'-biphenyl]-4-yl]diazenyl]-7-hydroxy-,disodium salt) (denoted as NPDA) into ZnAl-layered double hydroxides (LDHs) has been carried out by an anionexchange method in an effort to improve their thermal stability and light fastness.After intercalation of NPDA anions,the interlayer distance of the LDHs increases from 0.87 to 2.18nm,confirming their incorporation into the interlayer galleries of the LDHs host.Infrared spectroscopy and thermogravimetric analysis revealed the presence of host-guest interactions between LDHs layers and NPDA anions.The thermal stability of NPDA and ZnAl-NPDA-LDHs was compared by thermogravimetric-differential thermal analysis,UV-visible spectroscopy and infrared spectroscopy.It was found that the thermal stability of NPDA anions was markedly improved by incorporation into the ZnAl-LDHs matrix,while the light fastness was also enhanced.

  11. Exhaustive derivation of static self-consistent multi-soliton solutions in the matrix Bogoliubov-de Gennes systems

    CERN Document Server

    Takahashi, Daisuke A

    2015-01-01

    The matrix-generalized Bogoliubov-de Gennes systems are recently considered by the present author [arXiv:1509.04242], and the time-dependent and self-consistent multi-soliton solutions are constructed based on the ansatz method. In this paper, restricting the problem to the static case, we exhaustively determine the self-consistent solutions using the inverse scattering theory. Solving the gap equation, we rigorously prove that the self-consistent potential must be reflectionless. As a supplementary topic, we elucidate the relation between the stationary self-consistent potentials and the soliton solutions in the matrix nonlinear Schr\\"odinger equation. The asymptotic formulae of multi-soliton solutions for sufficiently isolated solitons are also presented.

  12. Systems solutions by lactic acid bacteria: from paradigms to practice.

    Science.gov (United States)

    de Vos, Willem M

    2011-08-30

    Lactic acid bacteria are among the powerhouses of the food industry, colonize the surfaces of plants and animals, and contribute to our health and well-being. The genomic characterization of LAB has rocketed and presently over 100 complete or nearly complete genomes are available, many of which serve as scientific paradigms. Moreover, functional and comparative metagenomic studies are taking off and provide a wealth of insight in the activity of lactic acid bacteria used in a variety of applications, ranging from starters in complex fermentations to their marketing as probiotics. In this new era of high throughput analysis, biology has become big science. Hence, there is a need to systematically store the generated information, apply this in an intelligent way, and provide modalities for constructing self-learning systems that can be used for future improvements. This review addresses these systems solutions with a state of the art overview of the present paradigms that relate to the use of lactic acid bacteria in industrial applications. Moreover, an outlook is presented of the future developments that include the transition into practice as well as the use of lactic acid bacteria in synthetic biology and other next generation applications.

  13. Evaluation of optimal reuse system for hydrofluoric acid wastewater

    Energy Technology Data Exchange (ETDEWEB)

    Won, Chan-Hee [Department of Environmental Engineering, Chonbuk National University, 567 Bakje-daero, Deokjin-Gu, Jeonju, Jeollabuk-Do, 561-756 (Korea, Republic of); Choi, Jeongyun [R and D Center, Samsung Engineering Co. Ltd., 415-10 Woncheon-Dong, Youngtong-Gu, Suwon, Gyeonggi-Do, 443-823 (Korea, Republic of); Chung, Jinwook, E-mail: jin-wook.chung@samsung.com [R and D Center, Samsung Engineering Co. Ltd., 415-10 Woncheon-Dong, Youngtong-Gu, Suwon, Gyeonggi-Do, 443-823 (Korea, Republic of)

    2012-11-15

    Highlights: Black-Right-Pointing-Pointer Coagulation and ion exchange technologies were ineffective in removing fluoride. Black-Right-Pointing-Pointer Polyamide RO was more efficacious than cellulose RO due to its high flux and rejection. Black-Right-Pointing-Pointer Spiral wound RO system was more preferential to disc tube RO system for reusing raw hydrofluoric acid wastewater. Black-Right-Pointing-Pointer Combined coagulation and RO technology can be applied to reuse raw hydrofluoric acid wastewater. - Abstract: The treatment of hydrofluoric acid (HF) wastewater has been an important environmental issue in recent years due to the extensive use of hydrofluoric acid in the chemical and electronics industries, such as semiconductor manufacturers. Coagulation/precipitation and ion exchange technologies have been used to treat HF wastewater, but these conventional methods are ineffective in removing organics, salts, and fluorides, limiting its reuse for water quality and economic feasibility. One promising alternative is reverse osmosis (RO) after lime treatment. Based on pilot-scale experiment using real HF wastewater discharged from semiconductor facility, the spiral wound module equipped with polyamide membranes has shown excellent flux and chemical cleaning cycles. Our results suggest that coagulation/precipitation and spiral wound RO constitute the optimal combination to reuse HF wastewater.

  14. Observability Analysis of a Matrix Kalman Filter-Based Navigation System Using Visual/Inertial/Magnetic Sensors

    Directory of Open Access Journals (Sweden)

    Guohu Feng

    2012-06-01

    Full Text Available A matrix Kalman filter (MKF has been implemented for an integrated navigation system using visual/inertial/magnetic sensors. The MKF rearranges the original nonlinear process model in a pseudo-linear process model. We employ the observability rank criterion based on Lie derivatives to verify the conditions under which the nonlinear system is observable. It has been proved that such observability conditions are: (a at least one degree of rotational freedom is excited, and (b at least two linearly independent horizontal lines and one vertical line are observed. Experimental results have validated the correctness of these observability conditions.

  15. MANAGEMENT MODEL OF UNCONFINED AQUIFER SYSTEM WITH SMALL THICKNESS WITH RESPECT TO DRAWDOWN BASED ON TWO-LEVEL RESPONSE MATRIX

    Institute of Scientific and Technical Information of China (English)

    Cai-Zhi SUN; Wei ZOU; Xue-Yu LIN

    2004-01-01

    In the management of unconfined aquifer systems, if the thickness of the aquifer is very small and the drawdown is relatively big, errors may arise when the superposition principle is adopted.directly. In allusion to this limitation, a new management model for the management of unconfined aquifer systems called two-level response matrix method is put forward. This method is applied in groundwater resources management in Shenyang city. The managing results show that this methodcan, in some degree, increase the efficiency of management and decrease the risk of management.

  16. Antioxidative activity of 3,4-dihydroxyplienylacetic acid and α-tocopherol on the triglyceride matrix of olive oil. Effect of acidity.

    Directory of Open Access Journals (Sweden)

    Blekas, Georgios

    1998-02-01

    Full Text Available Minor constituents of virgin olive oil are important for the remarkable stability of the oil in autoxidation, but the exact role and the extent to which each antioxidant factor contributes to the total antioxidant effect has not been thoroughly Investigated. In this study the role of α-tocopherol is explored at various acidity levels and at low concentrations of ortho-diphenols. A substrate of olive oil triacylglycerols devoid of prooxidant or antioxidant constituents was prepared from refined olive oil by column chromatography To tills substrate, slightly oxidized, the additives (oleic acid, 3,4-dihydroxyphenylacetic acid and α-tocopherol were added and the stability was assessed by periodical measurements of peroxide values. It was found that free fatty adds reduce mainly the protective activity of the ortho-diphenol. It is also concluded that α-tocopherol has a synergistic effect with the ortho-diphenols and contributes significantly to the retardation of peroxide formation. This is Important for oils poor in ortho-diphenols.

    Los constituyentes menores del aceite de oliva virgen son importantes para la notable estabilidad del aceite en la autooxidación, pero el papel exacto y el alcance con que cada factor antioxidante contribuye al efecto antioxidante total no ha sido investigado a fondo. En este estudio el papel del α-tocoferol es examinado a varios niveles de acidez y a baja concentraciones de o-difenoles. Un sustrato de triacilgliceroles de aceite de oliva desprovisto de constituyentes prooxidantes o antioxidantes fue preparado a partir de aceite de oliva refinado mediante cromatografía en columna. A este sustrato, un poco oxidado, los aditivos (ácido oleico, ácido 3,4-dihidroxifenilacético y α-tocoferol fueron añadidos y la estabilidad fue calculada mediante medidas periódicas del índice de peróxido. Se encontró que los ácidos grasos libres reducen principalmente la actividad protectora de los orto-difenoles. Se

  17. Probabilistic models and numerical calculation of system matrix and sensitivity in list-mode MLEM 3D reconstruction of Compton camera images.

    Science.gov (United States)

    Maxim, Voichita; Lojacono, Xavier; Hilaire, Estelle; Krimmer, Jochen; Testa, Etienne; Dauvergne, Denis; Magnin, Isabelle; Prost, Rémy

    2016-01-01

    This paper addresses the problem of evaluating the system matrix and the sensitivity for iterative reconstruction in Compton camera imaging. Proposed models and numerical calculation strategies are compared through the influence they have on the three-dimensional reconstructed images. The study attempts to address four questions. First, it proposes an analytic model for the system matrix. Second, it suggests a method for its numerical validation with Monte Carlo simulated data. Third, it compares analytical models of the sensitivity factors with Monte Carlo simulated values. Finally, it shows how the system matrix and the sensitivity calculation strategies influence the quality of the reconstructed images.

  18. An all-optical matrix multiplication scheme with non-linear material based switching system

    Institute of Scientific and Technical Information of China (English)

    Archan Kumar Das; Sourangshu Mukhopadhyay

    2005-01-01

    Optics is a potential candidate in information, data, and image processing. In all-optical data and information processing, optics has been used as information carrying signal because of its inherent advantages of parallelism. Several optical methods are proposed in support of the above processing. In many algebraic,arithmetic, and image processing schemes fundamental logic and memory operations are conducted exploring all-optical devices. In this communication we report an all-optical matrix multiplication operation with non-linear material based switching circuit.

  19. Matrix tablets based on thiolated poly(acrylic acid): pH-dependent variation in disintegration and mucoadhesion.

    Science.gov (United States)

    Guggi, Davide; Marschütz, Michaela K; Bernkop-Schnürch, Andreas

    2004-04-15

    This study examined the influence of the pH on the mucoadhesive and cohesive properties of polyarcylic acid (PAA) and thiolated PAA. The pH of PAA (molecular mass: 450 kDa) and of a corresponding PAA-cysteine conjugate was adjusted to 3, 4, 5, 6, 7 and 8. The amount of immobilised thiol groups and disulfide bonds was determined via Ellman's reagent. Tablets were compressed out of each pH-batch of both thiolated and unmodified PAA and the swelling behaviour, the disintegration time and the mucoadhesiveness were evaluated. The amount of thiol/disulfide groups per gram thiolated PAA of pH 3 and pH 8 was determined to be 332 +/- 94 micromol and 162 +/- 46 micromol, respectively. The thiolated PAA tablets displayed a minimum four-fold higher water uptake compared to unmodified PAA tablets. A faster and higher water uptake of both polymer types was observed above pH 5. Thiolated polymer tablets showed a 3-20-fold more prolonged disintegration time than unmodified PAA tablets. The cohesiveness of PAA-cysteine conjugate increased at higher pH, whereas the unmodified PAA behaved inversely. A 3-7-fold stronger mucoadhesiveness was observed for the PAA-cysteine conjugate tablets compared to unmodified PAA tablets. For both thiolated and unmodified polymer the mucoadhesiveness was 2-4-fold enhanced below pH 5. The difference in mucoadhesion between the two polymer types was most pronounced at these lower pH values. In this study substantial information regarding the pH-dependence of mucoadhesion and cohesion of unmodified polyacrylates and of thiolated polyacrylates is provided, representing helpful basic information for an ameliorated deployment of these polymers. PMID:15072786

  20. The incorporation of water-soluble gel matrix into bile acid-based microcapsules for the delivery of viable β-cells of the pancreas, in diabetes treatment: biocompatibility and functionality studies.

    Science.gov (United States)

    Mooranian, Armin; Negrulj, Rebecca; Al-Salami, Hani

    2016-02-01

    In recent studies, we microencapsulated pancreatic β-cells using sodium alginate (SA) and poly-L-ornithine (PLO) and the bile acid, ursodeoxycholic acid (UDCA), and tested the morphology and cell viability post-microencapsulation. Cell viability was low probably due to limited strength of the microcapsules. This study aimed to assess a β-cell delivery system which consists of UDCA-based microcapsules incorporated with water-soluble gel matrix. The polyelectrolytes, water-soluble gel (WSG), polystyrenic sulphate (PSS), PLO and polyallylamine (PAA) at ratios 4:1:1:2.5 with or without 4% UDCA, were incorporated into our microcapsules, and cell viability, metabolic profile, cell functionality, insulin production, levels of inflammation, microcapsule morphology, cellular distribution, UDCA partitioning, biocompatibility, thermal and chemical stabilities and the microencapsulation efficiency were examined. The incorporation of UDCA with PSS, PAA and WSG enhanced cell viability per microcapsule (p < 0.05), cellular metabolic profile (p < 0.01) and insulin production (p < 0.01); reduced the inflammatory release TNF-α (p < 0.01), INF-gamma (p < 0.01) and interleukin-6 (IL-6) (p < 0.01); and ceased the production of IL-1β. UDCA, PSS, PAA and WSG addition did not change the microencapsulation efficiency and resulted in biocompatible microcapsules. Our designed microcapsules showed good morphology and desirable insulin production, cell functionality and reduced inflammatory profile suggesting potential applications in diabetes.

  1. A hybrid finite element-transfer matrix model for vibroacoustic systems with flat and homogeneous acoustic treatments.

    Science.gov (United States)

    Alimonti, Luca; Atalla, Noureddine; Berry, Alain; Sgard, Franck

    2015-02-01

    Practical vibroacoustic systems involve passive acoustic treatments consisting of highly dissipative media such as poroelastic materials. The numerical modeling of such systems at low to mid frequencies typically relies on substructuring methodologies based on finite element models. Namely, the master subsystems (i.e., structural and acoustic domains) are described by a finite set of uncoupled modes, whereas condensation procedures are typically preferred for the acoustic treatments. However, although accurate, such methodology is computationally expensive when real life applications are considered. A potential reduction of the computational burden could be obtained by approximating the effect of the acoustic treatment on the master subsystems without introducing physical degrees of freedom. To do that, the treatment has to be assumed homogeneous, flat, and of infinite lateral extent. Under these hypotheses, simple analytical tools like the transfer matrix method can be employed. In this paper, a hybrid finite element-transfer matrix methodology is proposed. The impact of the limiting assumptions inherent within the analytical framework are assessed for the case of plate-cavity systems involving flat and homogeneous acoustic treatments. The results prove that the hybrid model can capture the qualitative behavior of the vibroacoustic system while reducing the computational effort.

  2. THE HIGH RESOLUTION MIMO RADAR SYSTEM BASED ON MINIMIZING THE STATISTICAL COHERENCE OF COMPRESSED SENSING MATRIX

    Institute of Scientific and Technical Information of China (English)

    Zhu Yanping; Song Yaoliang; Chen Jinli; Zhao Delin

    2012-01-01

    Compressed Sensing (CS) theory is a great breakthrough of the traditional Nyquist sampling theory.It can accomplish compressive sampling and signal recovery based on the sparsity of interested signal,the randomness of measurement matrix and nonlinear optimization method of signal recovery.Firstly,the CS principle is reviewed.Then the ambiguity function of Multiple-Input Multiple-Output (MIMO) radar is deduced.After that,combined with CS theory,the ambiguity function of MIMO radar is analyzed and simulated in detail.At last,the resolutions of coherent and non-coherent MIMO radars on the CS theory are discussed.Simulation results show that the coherent MIMO radar has better resolution performance than the non-coherent.But the coherent ambiguity function has higher side lobes,which caused a deterioration in radar target detection performances.The stochastic embattling method of sparse array based on minimizing the statistical coherence of sensing matrix is proposed.And simulation results show that it could effectively suppress side lobes of the ambiguity function and improve the capability of weak target detection.

  3. The Significance of Matrix Metalloproteinases in Parasitic Infections Involving the Central Nervous System

    Directory of Open Access Journals (Sweden)

    Fabrizio Bruschi

    2013-02-01

    Full Text Available Matrix metalloproteinases (MMPs represent a large family of over twenty different secreted or membrane-bound endopeptidases, involved in many physiological (embryogenesis, precursor or stem cell mobilization, tissue remodeling during wound healing, etc., as well as pathological (inflammation, tumor progression and metastasis in cancer, vascular pathology, etc. conditions. For a long time, MMPs were considered only for the ability to degrade extracellular matrix (ECM molecules (e.g., collagen, laminin, fibronectin and to release hidden epitopes from the ECM. In the last few years, it has been fully elucidated that these molecules have many other functions, mainly related to the immune response, in consideration of their effects on cytokines, hormones and chemokines. Among others, MMP-2 and MMP-9 are endopeptidases of the MMP family produced by neutrophils, macrophages and monocytes. When infection is associated with leukocyte influx into specific organs, immunopathology and collateral tissue damage may occur. In this review, the involvement of MMPs and, in particular, of gelatinases in both protozoan and helminth infections will be described. In cerebral malaria, for example, MMPs play a role in the pathogenesis of such diseases. Also, trypanosomosis and toxoplasmosis will be considered for protozoan infections, as well as neurocysticercosis and angiostrongyloidosis, as regards helminthiases. All these situations have in common the proteolytic action on the blood brain barrier, mediated by MMPs.

  4. Developments of theory of effective prepotential from extended Seiberg-Witten system and matrix models

    CERN Document Server

    Itoyama, Hiroshi

    2015-01-01

    This is a semi-pedagogical review of a medium size on the exact determination of and the role played by the low energy effective prepotential ${\\cal F}$ in QFT with (broken) extended supersymmetry, which began with the work of Seiberg and Witten in 1994. While paying an attention to an overall view of this subject lasting long over the two decades, we probe several corners marked in the three major stages of the developments, emphasizing uses of the deformation theory on the attendant Riemann surface as well as its close relation to matrix models. Examples picked here in different contexts tell us that the effective prepotential is to be identified as the suitably defined free energy $F$ of a matrix model: ${\\cal F} = F$. To be submitted to PTEP as an invited review article and based in part on the talk delivered by one of the authors (H.I.) in the workshop held at Shizuoka University, Shizuoka, Japan, on December 5, 2014.

  5. Effects of organic acids, amino acids and ethanol on the radio-degradation of patulin in an aqueous model system

    Energy Technology Data Exchange (ETDEWEB)

    Yun, Hyejeong [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Chonbuk, Jeongeup 580-185 (Korea, Republic of); Department of Food Science and Technology, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Lim, Sangyong [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Chonbuk, Jeongeup 580-185 (Korea, Republic of); Jo, Cheorun [Department of Animal Science and Biotechnology, Chungnam National University, Daejeon 305-764 (Korea, Republic of); Chung, Jinwoo [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Chonbuk, Jeongeup 580-185 (Korea, Republic of); Kim, Soohyun [Glycomics Team, Korea Basic Science Institute, Daejeon 305-333 (Korea, Republic of); Kwon, Joong-Ho [Department of Food Science and Technology, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Kim, Dongho [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Chonbuk, Jeongeup 580-185 (Korea, Republic of)], E-mail: fungikim@kaeri.re.kr

    2008-06-15

    The effects of organic acids, amino acids, and ethanol on the radio-degradation of patulin by gamma irradiation in an aqueous model system were investigated. The patulin, dissolved in distilled water at a concentration of 50 ppm, was practically degraded by the gamma irradiation at the dose of 1.0 kGy, while 33% of the patulin remained in apple juice. In the aqueous model system, the radio-degradation of patulin was partially inhibited by the addition of organic acids, amino acids, and ethanol. The proportions of remaining patulin after irradiation with the dose of 1.0 kGy in the 1% solution of malic acid, citric acid, lactic acid, acetic acid, ascorbic acid, and ethanol were 31.4%, 2.3%, 31.2%, 6.1%, 50.8%, and 12.5%, respectively. During 30 days of storage, the remaining patulin was reduced gradually in the solution of ascorbic acid and malic acid compared to being stable in other samples. The amino acids, serine, threonine, and histidine, inhibited the radio-degradation of patulin. In conclusion, it was suggested that 1 kGy of gamma irradiation (recommended radiation doses for radicidation and/or quarantine in fruits) is effective for the reduction of patulin, but the nutritional elements should be considered because the radio-degradation effects are environment dependent.

  6. System for portable nucleic acid testing in low resource settings

    Science.gov (United States)

    Lu, Hsiang-Wei; Roskos, Kristina; Hickerson, Anna I.; Carey, Thomas; Niemz, Angelika

    2013-03-01

    Our overall goal is to enable timely diagnosis of infectious diseases through nucleic acid testing at the point-of-care and in low resource settings, via a compact system that integrates nucleic acid sample preparation, isothermal DNA amplification, and nucleic acid lateral flow (NALF) detection. We herein present an interim milestone, the design of the amplification and detection subsystem, and the characterization of thermal and fluidic control and assay execution within this system. Using an earlier prototype of the amplification and detection unit, comprised of a disposable cartridge containing flexible pouches, passive valves, and electrolysis-driven pumps, in conjunction with a small heater, we have demonstrated successful execution of an established and clinically validated isothermal loop-mediated amplification (LAMP) reaction targeting Mycobacterium tuberculosis (M.tb) DNA, coupled to NALF detection. The refined design presented herein incorporates miniaturized and integrated electrolytic pumps, novel passive valves, overall design changes to facilitate integration with an upstream sample preparation unit, and a refined instrument design that automates pumping, heating, and timing. Nucleic acid amplification occurs in a two-layer pouch that facilitates fluid handling and appropriate thermal control. The disposable cartridge is manufactured using low-cost and scalable techniques and forms a closed system to prevent workplace contamination by amplicons. In a parallel effort, we are developing a sample preparation unit based on similar design principles, which performs mechanical lysis of mycobacteria and DNA extraction from liquefied and disinfected sputum. Our next step is to combine sample preparation, amplification, and detection in a final integrated cartridge and device, to enable fully automated sample-in to answer-out diagnosis of active tuberculosis in primary care facilities of low-resource and high-burden countries.

  7. Some fundamental aspects of fault-tree and digraph-matrix relationships for a systems-interaction evaluation procedure

    International Nuclear Information System (INIS)

    Recent events, such as Three Mile Island-2, Brown's Ferry-3, and Crystal River-3, have demonstrated that complex accidents can occur as a result of dependent (common-cause/mode) failures. These events are now being called Systems Interactions. A procedure for the identification and evaluation of Systems Interactions is being developed by the NRC. Several national laboratories and utilities have contributed preliminary procedures. As a result, there are several important views of the Systems Interaction problem. This report reviews some fundamental mathematical background of both fault-oriented and success-oriented risk analyses in order to bring out the advantages and disadvantages of each. In addition, it outlines several fault-oriented/dependency analysis approaches and several success-oriented/digraph-matrix approaches. The objective is to obtain a broad perspective of present options for solving the Systems Interaction problem

  8. M-matrix strategies for pinning-controlled leader-following consensus in multiagent systems with nonlinear dynamics.

    Science.gov (United States)

    Song, Qiang; Liu, Fang; Cao, Jinde; Yu, Wenwu

    2013-12-01

    This paper considers the leader-following consensus problem for multiagent systems with inherent nonlinear dynamics. Some M-matrix strategies are developed to address several challenging issues in the pinning control of multiagent systems by using algebraic graph theory and the properties of nonnegative matrices. It is shown that second-order leader-following consensus in a nonlinear multiagent system can be reached if the virtual leader has a directed path to every follower and a derived quantity is greater than a positive threshold. In particular, this paper analytically proves that leader-following consensus may be easier to be achieved by pinning more agents or increasing the pinning feedback gains. A selective pinning scheme is then proposed for nonlinear multiagent systems with directed network topologies. Numerical results are given to verify the theoretical analysis. PMID:24273144

  9. 21 CFR 862.1390 - 5-Hydroxyindole acetic acid/serotonin test system.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false 5-Hydroxyindole acetic acid/serotonin test system... Test Systems § 862.1390 5-Hydroxyindole acetic acid/serotonin test system. (a) Identification. A 5-hydroxyindole acetic acid/serotonin test system is a device intended to measure 5-hydroxyindole acetic...

  10. 21 CFR 862.1020 - Acid phosphatase (total or prostatic) test system.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Acid phosphatase (total or prostatic) test system... Test Systems § 862.1020 Acid phosphatase (total or prostatic) test system. (a) Identification. An acid phosphatase (total or prostatic) test system is a device intended to measure the activity of the...

  11. Pump design for High Temperature Sulfuric acid transfer system

    International Nuclear Information System (INIS)

    In the sulfuric acid concentration / decomposition section, consequent issues handling material corrosion and the coupling with high temperature energy source were generated, as well as the study of catalyst activity and stability. And Onuki et al., mentioned that material resistance issues are also important for the development of the hydriodic acid concentration/decomposition section. Moreover, the transfer of high temperature H2SO4 is a very important factor considering safety in successive reaction process and efficiency. As mentioned above, the pump to carry sulfuric acid is very important in SI process, but this study is insufficient. After forced cooling of high temperature H2SO4, reduction of safety and process efficiency which is caused by transfer, re-heating, and pressurization is one of the weaknesses in H2SO4 transfer system. Therefore, in this study, we proposed the newly designed H2SO4 transfer system for SI thermo-chemical cycle and the proposed H2SO4 transfer system was analyzed using computational fluid dynamics (CFD) analysis in order to investigate thermodynamic /hydrodynamic characteristics. As the results, we identify as follows as: By the thermal analysis result of bellows in developed transfer system, it is verified that continuous operation is possible within the deformation temperature limit of Teflon 430 K. Physical/chemical environment of inside the bellows box and performance of bellows in continuous operation condition were evaluated. It is verified that not only the bellows, but also the end-plate made of STS can provide reliability and durability during continuous operation. The CFD results on thermohydrodynamic characteristics show good performance for the proposed H2SO4 transfer system. It is evaluated that it will be efficient in actual manufacturing process because it can provide quantitative transfer and prevent heat loss

  12. Hyaluronic acid based hydrogel system for soft tissue regeneration and drug delivery

    Science.gov (United States)

    Jha, Amit Kumar

    We have developed hyaluronic acid (HA)-based, biomimetic hydrogel matrices that are hierarchically structured, mechanically robust and biologically active. Specifically, HA-based hydrogel particles (HGPs) with controlled sizes, defined porosity, and improved stability were synthesized using different inverse emulsion systems and crosslinking chemistries. The resultant particles either contained residual functional groups or were rendered reactive by subsequent chemical modifications. HA-based doubly crosslinked networks (DXNs) were synthesized via covalent crosslinking of HA HGPs with soluble HA macromers carrying mutually reactive functional groups. These hybrid matrices are hierarchical in nature, consisting of densely crosslinked HGPs integrated in a loosely connected secondary matrix. Their mechanical properties and degradation kinetics can be readily tuned by varying the particle size, functional group density, intra- and interparticle crosslinking. To improve the biological functions of HA HGPs, perlecan domain I (PlnDI), a basement membrane proteoglycan that has strong affinity for various heparin binding growth factors (HBGFs), was successfully conjugated to the particles through the core protein via a flexible poly(ethylene glycol) (PEG) linker. The immobilized PlnDI maintains its ability to bind bone morphogenetic proteins (BMP-2) and modulates its in vitro release. A similar, sustained release of BMP-2 was achieved by encapsulating BMP-2-loaded HGPs within a photocrosslinked HA matrix. When encapsulated in HA DXNs, primary bovine chondrocytes were able to maintain their phenotype, proliferate readily and produce abundant glycosaminoglycan. Finally, cell-adhesive HA DXNs were fabricated by encapsulating gelatin-decorated HA HGPs in a secondary HA matrix. Human MSCs were shown to adhere to the composite matrix through the focal adhesion sites clustered on particle surface. The cell-adhesive composite matrices supported hMSC proliferation and migration into

  13. Group classification of systems of non-linear reaction-diffusion equations with general diffusion matrix. I. Generalized Landau-Ginzburg equations

    OpenAIRE

    Nikitin, A. G.

    2004-01-01

    Group classification of the generalized complex Ginzburg-Landau equations is presented. An approach to group classification of systems of reaction-diffusion equations with general diffusion matrix is developed.

  14. R-matrix Analysis for the 8Be System and Features in the p+7Li Reaction Over Resonance Region

    Directory of Open Access Journals (Sweden)

    Kunieda Satoshi

    2016-01-01

    Full Text Available A comprehensive R-matrix analysis is currently underway for the 8Be compound system toward a consistent evaluation of the p+7Li reaction cross-sections over the resonance energy region. In this analysis, the energy eigenvalues are fixed to the level energies given in ENSDF, and we searched for values of the boundary condition parameters as well as the reduced-width amplitudes. It is found that some additional levels are necessary to fit the resonant shape of experimental cross-sections. Besides, the channel radii obtained may be consistent with well-known physical pictures of the atomic nucleus.

  15. Resin Systems and Chemistry-Degradation Mechanisms and Durability in Long-Term Durability of Polymeric Matrix Composites. Chapter 1

    Science.gov (United States)

    Hinkley, Jeffrey A.; Connell, John W.

    2012-01-01

    In choosing a polymer-matrix composite material for a particular application, a number of factors need to be weighed. Among these are mechanical requirements, fabrication method (e.g. press-molding, resin infusion, filament winding, tape layup), and use conditions. Primary among the environmental exposures encountered in aerospace structures are moisture and elevated temperatures, but certain applications may require resistance to other fluids and solvents, alkaline agents, thermal cycling, radiation, or rapid, localized heating (for example, lightning strike). In this chapter, the main classes of polymer resin systems found in aerospace composites will be discussed. Within each class, their responses to environmental factors and the associated degradation mechanisms will be reviewed.

  16. R-matrix Analysis for the 8Be System and Features in the p+7Li Reaction Over Resonance Region

    Science.gov (United States)

    Kunieda, Satoshi

    2016-06-01

    A comprehensive R-matrix analysis is currently underway for the 8Be compound system toward a consistent evaluation of the p+7Li reaction cross-sections over the resonance energy region. In this analysis, the energy eigenvalues are fixed to the level energies given in ENSDF, and we searched for values of the boundary condition parameters as well as the reduced-width amplitudes. It is found that some additional levels are necessary to fit the resonant shape of experimental cross-sections. Besides, the channel radii obtained may be consistent with well-known physical pictures of the atomic nucleus.

  17. Statistical Analysis of the Figure of Merit of a Two-Level Thermoelectric System: A Random Matrix Approach

    Science.gov (United States)

    Abbout, Adel; Ouerdane, Henni; Goupil, Christophe

    2016-09-01

    Using the tools of random matrix theory we develop a statistical analysis of the transport properties of thermoelectric low-dimensional systems made of two electron reservoirs set at different temperatures and chemical potentials, and connected through a low-density-of-states two-level quantum dot that acts as a conducting chaotic cavity. Our exact treatment of the chaotic behavior in such devices lies on the scattering matrix formalism and yields analytical expressions for the joint probability distribution functions of the Seebeck coefficient and the transmission profile, as well as the marginal distributions, at arbitrary Fermi energy. The scattering matrices belong to circular ensembles which we sample to numerically compute the transmission function, the Seebeck coefficient, and their relationship. The exact transport coefficients probability distributions are found to be highly non-Gaussian for small numbers of conduction modes, and the analytical and numerical results are in excellent agreement. The system performance is also studied, and we find that the optimum performance is obtained for half-transparent quantum dots; further, this optimum may be enhanced for systems with few conduction modes.

  18. Quantum propagation and confinement in 1D systems using the transfer-matrix method

    International Nuclear Information System (INIS)

    The aim of this article is to provide some Matlab scripts to the teaching community in quantum physics. The scripts are based on the transfer-matrix formalism and offer a very efficient and versatile tool to solve problems of a physical object (electron, proton, neutron, etc) with one-dimensional (1D) stationary potential energy. Resonant tunnelling through a multiple-barrier or confinement in wells of various shapes is particularly analysed. The results are quantitatively discussed with semiconductor heterostructures, harmonic and anharmonic molecular vibrations, or neutrons in a gravity field. Scripts and other examples (hydrogen-like ions and transmission by a smooth variation of potential energy) are available freely at http://www-loa.univ-lille1.fr/~pujol in three languages: English, French and Spanish. (paper)

  19. Quantum propagation and confinement in 1D systems using the transfer-matrix method

    Science.gov (United States)

    Pujol, Olivier; Carles, Robert; Pérez, José-Philippe

    2014-05-01

    The aim of this article is to provide some Matlab scripts to the teaching community in quantum physics. The scripts are based on the transfer-matrix formalism and offer a very efficient and versatile tool to solve problems of a physical object (electron, proton, neutron, etc) with one-dimensional (1D) stationary potential energy. Resonant tunnelling through a multiple-barrier or confinement in wells of various shapes is particularly analysed. The results are quantitatively discussed with semiconductor heterostructures, harmonic and anharmonic molecular vibrations, or neutrons in a gravity field. Scripts and other examples (hydrogen-like ions and transmission by a smooth variation of potential energy) are available freely at http://www-loa.univ-lille1.fr/˜pujol in three languages: English, French and Spanish.

  20. Comparison of metoprolol tartrate multiple-unit lipid matrix systems produced by different technologies.

    Science.gov (United States)

    Aleksovski, Aleksandar; Van Bockstal, Pieter-Jan; Roškar, Robert; Sovány, Tamás; Regdon, Géza; De Beer, Thomas; Vervaet, Chris; Dreu, Rok

    2016-06-10

    The aim of this study was to develop, evaluate and compare extended release mini-matrices based on metoprolol tartrate (MPT) and either glyceryl behenate (GB) or glyceryl palmitostearate (GPS). Mini-matrices were produced by three different techniques: hot melt extrusion, compression of melt granulates and prilling. Hot-melt extrusion and compression of granules obtained from melted material proved to be reliable, robust and reproducible techniques with aim of obtaining extended release matrices. Prilling tended to be susceptible to increased melt viscosity. Direct compression was not applicable for mini-matrix production due to poor powder flow. In general MPT release from all matrices was affected by its loading and the size of the units/particles. Processing of GB-MPT mixtures by different techniques did not lead to different drug release rates and patterns, while in case of GPS differently obtained matrices provided diverse MPT release outcomes. Matrices based on GB tended to have higher porosity compared to ones composed of GPS and thus most of the GB-based formulations showed faster drug delivery. FT-IR analysis revealed no interactions between primary components used for matrix production and Raman mapping outlined uniform MPT distribution throughout the units. DSC and X-ray studies revealed significant changes in the crystallinity of glycerides after storage under room conditions (GPS samples) and at increased temperature (GB and GPS samples), which was correlated to the changes seen in drug release rate and pattern after storage. Media composition in general tended to insignificantly affect GB matrices, while in case of GPS matrices increasing the pH and presence of biorelevant compounds induced faster drug release. PMID:26980237

  1. A METHOD OF CONSTRUCTING A MATRIX OF STATES OF THE DIAGNOSTIC PARAMETERS OF BRAKE SYSTEM OF A CAR

    Directory of Open Access Journals (Sweden)

    Uspensky I. A.

    2014-05-01

    Full Text Available The article describes the method of determining the list of rational diagnostic parameters of the brake system of a vehicle using the theory of probability and mathematical statistics. The problems determining the statistical probabilities of failures on objects considered a run; mathematical models (regression dependence the probability of failure of run; A statistical evaluation of the significance of the coefficients of regression models; verification has been made on the adequacy of the regression models; the probabilities of possible states of objects. On the basis of the construction and analysis of structural- effect model brake system information and calculates the importance of each monitored parameter using the notion of information entropy, determine the parameters to be diagnostic, and builds a matrix condition of brake systems for non-destructive testing, in order to move on maintenance and repair of the actual state

  2. The factorization method for systems with a complex action. A test in random matrix theory for finite density QCD

    International Nuclear Information System (INIS)

    Monte Carlo simulations of systems with a complex action are known to be extremely difficult. A new approach to this problem based on a factorization property of distribution functions of observables has been proposed recently. The method can be applied to any system with a complex action, and it eliminates the so-called overlap problem completely. We test the new approach in a Random Matrix Theory for finite density QCD, where we are able to reproduce the exact results for the quark number density. The achieved system size is large enough to extract the thermodynamic limit. Our results provide a clear understanding of how the expected first order phase transition is induced by the imaginary part of the action. (author)

  3. Creep Behavior of Hafnia and Ytterbium Silicate Environmental Barrier Coating Systems on SiC/SiC Ceramic Matrix Composites

    Science.gov (United States)

    Zhu, Dongming; Fox, Dennis S.; Ghosn, Louis J.; Harder, Bryan

    2011-01-01

    Environmental barrier coatings will play a crucial role in future advanced gas turbine engines because of their ability to significantly extend the temperature capability and stability of SiC/SiC ceramic matrix composite (CMC) engine components, thus improving the engine performance. In order to develop high performance, robust coating systems for engine components, appropriate test approaches simulating operating temperature gradient and stress environments for evaluating the critical coating properties must be established. In this paper, thermal gradient mechanical testing approaches for evaluating creep and fatigue behavior of environmental barrier coated SiC/SiC CMC systems will be described. The creep and fatigue behavior of Hafnia and ytterbium silicate environmental barrier coatings on SiC/SiC CMC systems will be reported in simulated environmental exposure conditions. The coating failure mechanisms will also be discussed under the heat flux and stress conditions.

  4. Reduction of inflammatory responses and enhancement of extracellular matrix formation by vanillin-incorporated poly(lactic-co-glycolic acid) scaffolds.

    Science.gov (United States)

    Lee, Yujung; Kwon, Jeongil; Khang, Gilson; Lee, Dongwon

    2012-10-01

    Vanillin is one of the major components of vanilla, a commonly used flavoring agent and preservative and is known to exert potent antioxidant and anti-inflammatory activities. In this work, vanillin-incorporated poly(lactic-co-glycolic acid) (PLGA) films and scaffolds were fabricated to evaluate the effects of vanillin on the inflammatory responses and extracellular matrix (ECM) formation in vitro and in vivo. The incorporation of vanillin to PLGA films induced hydrophilic nature, resulting in the higher cell attachment and proliferation than the pure PLGA film. Vanillin also reduced the generation of reactive oxygen species (ROS) in cells cultured on the pure PLGA film and significantly inhibited the PLGA-induced inflammatory responses in vivo, evidenced by the reduced accumulation of inflammatory cells and thinner fibrous capsules. The effects of vanillin on the ECM formation were evaluated using annulus fibrous (AF) cell-seeded porous PLGA/vanillin scaffolds. PLGA/vanillin scaffolds elicited the more production of glycosaminoglycan and collagen than the pure PLGA scaffold, in a concentration-dependent manner. Based on the low level of inflammatory responses and enhanced ECM formation, vanillin-incorporated PLGA constructs make them promising candidates in the future biomedical applications.

  5. Caffeic Acid Phenethyl Ester Inhibits Oral Cancer Cell Metastasis by Regulating Matrix Metalloproteinase-2 and the Mitogen-Activated Protein Kinase Pathway

    Directory of Open Access Journals (Sweden)

    Chih-Yu Peng

    2012-01-01

    Full Text Available Caffeic acid phenethyl ester (CAPE, an active component extracted from honeybee hives, exhibits anti-inflammatory and anticancer activities. However, the molecular mechanism by which CAPE affects oral cancer cell metastasis has yet to be elucidated. In this study, we investigated the potential mechanisms underlying the effects of CAPE on the invasive ability of SCC-9 oral cancer cells. Results showed that CAPE attenuated SCC-9 cell migration and invasion at noncytotoxic concentrations (0 μM to 40 μM. Western blot and gelatin zymography analysis findings further indicated that CAPE downregulated matrix metalloproteinase-2 (MMP-2 protein expression and inhibited its enzymatic activity. CAPE exerted its inhibitory effects on MMP-2 expression and activity by upregulating tissue inhibitor of metalloproteinase-2 (TIMP-2 and potently decreased migration by reducing focal adhesion kinase (FAK phosphorylation and the activation of its downstream signaling molecules p38/MAPK and JNK. These data indicate that CAPE could potentially be used as a chemoagent to prevent oral cancer metastasis.

  6. A Novel MALDI Matrix for Analyzing Peptides and Proteins: Paraffin Wax Immobilized Matrix

    Institute of Scientific and Technical Information of China (English)

    WEI Yuanlong; MEI Yuan; XU Zhe; WANG Cuihong; GUO Yinlong; DU Yiping; ZHANG Weibing

    2009-01-01

    A new kind of MALDI matrix, termed paraffin wax immobilized matrix, was used to study peptide mixtures and proteins. During the preparation process, the paraffin wax was heated and coated on the stainless-steel target plate, and then 2,5-dihydrobenzoic acid (DHB) was deposited on the paraffin layer and stainless-steel target plate to obtain different kinds of matrix spots. The morphology of matrices on different supports and peptide-matrix co-crystallization were observed by a high resolution digital-video microscopy system. Peptide mixtures and bovine serum albumin (BSA) digests were used to investigate the performance of the immobilized matrices on the paraffin target. The MALDI-FTMS analysis results also showed that the detection sensitivity of matrices immobilized in the paraffin sample support was better than that on other sample supports.

  7. Dietary amino acid-induced systemic lupus erythematosus.

    Science.gov (United States)

    Montanaro, A; Bardana, E J

    1991-05-01

    The effects of dietary manipulations on autoimmune disease are understood poorly. In this article, we detail our experience with a human subject who developed autoimmune hemolytic anemia while participating in a research study that required the ingestion of alfalfa seeds. Subsequent experimental studies in primates ingesting alfalfa sprout seeds and L-canavanine (a prominent amino acid constituent of alfalfa) is presented. The results of these studies indicate a potential toxic and immunoregulatory role of L-canavanine in the induction of a systemic lupus-like disease in primates. PMID:1862241

  8. Results of electric-vehicle propulsion system performance on three lead-acid battery systems

    Science.gov (United States)

    Ewashinka, J. G.

    1984-01-01

    Three types of state of the art 6 V lead acid batteries were tested. The cycle life of lead acid batteries as a function of the electric vehicle propulsion system design was determined. Cycle life, degradation rate and failure modes with different battery types (baseline versus state of the art tubular and thin plate batteries) were compared. The effects of testing strings of three versus six series connected batteries on overall performance were investigated. All three types do not seem to have an economically feasible battery system for the propulsion systems. The tubular plate batteries on the load leveled profile attained 235 cycles with no signs of degradation and minimal capacity loss.

  9. FORMULATION AND EVALUATION OF MATRIX TYPE TRANSDERMAL SYSTEM OF LISINOPRIL DIHYDRATE

    Directory of Open Access Journals (Sweden)

    Suchetha Reddy Aleti

    2011-06-01

    Full Text Available Lisinopril is a drug of class angiotensin converting enzyme (ACE inhibitor that is primarily used in treatment of hypertension, congestive heart failure, heart attacks and also in preventing renal and retinal complications of diabetes. If it is given orally, there may be severe hepatic first pass metabolism as a result there is reduction in the bioavailability (6-60%. In order to increase the bioavailability of the lisinopril, transdermal films were formulated using different polymer combinations such as hydrophilic (hydroxy propyl methyl cellulose: poly vinyl pyrrolidone and combination of lipophillic- hydrophilic polymers (ethyl cellulose: poly vinyl pyrrolidone in different ratios. The prepared films were evaluated for thickness, folding endurance, drug content uniformity, tensile strength, percent moisture uptake, percent moisture loss, in-vitro skin permeation study. In-vitro drug release study through sigma membrane indicated that hydrophilic polymer combinations have shown greater drug release than the hydrophilic-lipophillic polymer combinations. By fitting the data into zero order, first order and Higuchi model, it was concluded that drug release from matrix films followed Higuchi model and the mechanism of release was diffusion mediated.

  10. Embryonic and postnatal development of the layer I-directed ("matrix") thalamocortical system in the rat.

    Science.gov (United States)

    Galazo, Maria J; Martinez-Cerdeño, Verónica; Porrero, César; Clascá, Francisco

    2008-02-01

    Inputs to the layer I apical dendritic tufts of pyramidal cells are crucial in "top-down" interactions in the cerebral cortex. A large population of thalamocortical cells, the "matrix" (M-type) cells, provides a direct robust input to layer I that is anatomically and functionally different from the thalamocortical input to layer VI. The developmental timecourse of M-type axons is examined here in rats aged E (embryonic day) 16 to P (postnatal day) 30. Anterograde techniques were used to label axons arising from 2 thalamic nuclei mainly made up of M-type cells, the Posterior and the Ventromedial. The primary growth cones of M-type axons rapidly reached the subplate of dorsally situated cortical areas. After this, interstitial branches would sprout from these axons under more lateral cortical regions to invade the overlying cortical plate forming secondary arbors. Moreover, retrograde labeling of M-type cell somata in the thalamus after tracer deposits confined to layer I revealed that large numbers of axons from multiple thalamic nuclei had already converged in a given spot of layer I by P3. Because of early ingrowth in such large numbers, interactions of M-type axons may significantly influence the early development of cortical circuits.

  11. Quantum information aspects on bulk and nano interacting Fermi system: A spin-space density matrix approach

    Science.gov (United States)

    Afzali, R.; Ebrahimian, N.; Eghbalifar, B.

    2016-10-01

    By approximating the energy gap, entering nano-size effect via gap fluctuation and calculating the Green's functions and the space-spin density matrix, the dependence of quantum correlation (entanglement, discord and tripartite entanglement) on the relative distance of two electron spins forming Cooper pairs, the energy gap and the length of bulk and nano interacting Fermi system (a nodal d-wave superconductor) is determined. In contrast to a s-wave superconductor, quantum correlation of the system is sensitive to the change of the gap magnitude and strongly depends on the length of the grain. Also, quantum discord oscillates. Furthermore, the entanglement length and the correlation length are investigated. Discord becomes zero at a characteristic length of the d-wave superconductor.

  12. Development Status and Performance Comparisons of Environmental Barrier Coating Systems for SiCSiC Ceramic Matrix Composites

    Science.gov (United States)

    Zhu, Dongming; Harder, Bryan

    2016-01-01

    Environmental barrier coatings (EBC) and SiCSiC ceramic matrix composites (CMCs) will play a crucial role in future aircraft turbine engine systems, because of their ability to significantly increase engine operating temperatures, reduce engine weight and cooling requirements. This paper presents current NASA EBC-CMC development emphases including: the coating composition and processing improvements, laser high heat flux-thermal gradient thermo-mechanical fatigue - environmental testing methodology development, and property evaluations for next generation EBC-CMC systems. EBCs processed with various deposition techniques including Plasma Spray, Electron Beam - Physical Vapor Deposition, and Plasma Spray Physical Vapor Deposition (PS-PVD) will be particularly discussed. The testing results and demonstrations of advanced EBCs-CMCs in complex simulated engine thermal gradient cyclic fatigue, oxidizing-steam and CMAS environments will help provide insights into the coating development strategies to meet long-term engine component durability goals.

  13. 21 CFR 862.1187 - Conjugated sulfolithocholic acid (SLCG) test system.

    Science.gov (United States)

    2010-04-01

    ... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems § 862.1187 Conjugated sulfolithocholic acid (SLCG) test system. (a) Identification....

  14. New initiation system for polymerization of acryl acid

    Institute of Scientific and Technical Information of China (English)

    LI Hai-pu; ZHONG Hong; CHEN Qi-yuan; YIN Zhou-lan

    2005-01-01

    The redox initiation system for polyacrylate sodium of high molecular mass was designed and its effect with varying component dosage on the degree of polymerization was investigated. The results show that the proper type and amount of inorganic salt, as well as amine initiator, are conductive to the increase of degree of polymerization. The fine ingredient of the initiation system is as follows:the dosages of amine, persulphate and inorganic salt are 0.75%, 0.10% and 1.00% by mass based on acryl acid respectively, the molar ratio of sulphite to the persulphate is 1:1. Under such conditions the degree of polyacrylate can reach 7.43×107 with a acceptable polymerization time for industrial production.

  15. Digraph Matrix Analysis for systems interactions at Indian Point Unit 3. Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    Alesso, H.P.; Altenbach, T.J.; Prassinos, P.G.; Lappa, D.A.; Kimura, C.Y.; Patenaude, C.J.; Sacks, I.J.; Ashmore, B.C.; Fromme, D.C.; Hershberger, M.V.

    1986-01-01

    This report documents the analysis of the Indian Point Plant, Unit 3 (IP-3) for adverse systems interactions using DMA. The primary objective of the study was to compare the effectiveness of DMA in finding systems interactions. To this end a parallel study was funded at Brookhaven National Laboratory (BNL). The results of this study and the BNL study will then be compared by NRC to the results of a similar study performed by the Power Authority of the State of New York. A secondary objective of this study was to determine systems interactions in selected combinations of safety systems at IP-3. 24 refs., 22 figs., 29 tabs.

  16. A positioning model of a two CCD camera coordinate system with an alternate-four-matrix look-up table algorithm

    Science.gov (United States)

    Lin, Chern-Sheng; Chen, Chia-Tse; Wei, Tzu-Chi; Chen, Wei-Lung; Chang, Chia-Chang

    2010-12-01

    This study proposes a novel positioning model of a two CCD camera coordinate system with an alternate-four-matrix (AFM) look-up table (LUT) algorithm. Two CCD cameras are set on both sides of a large scale screen and used to aid the position measures of targets. The coordinate position of the object in a specified space can be obtained by using different viewing angles of the two cameras and the AFMLUT method. The right camera is in charge of detecting the intermediate block near the right side and the dead zone of the left camera, using the first and the second matrix LUTs. The left camera is in charge of detecting the other parts, using the third and the fourth matrix LUTs. The results indicate that this rapid mapping and four matrix memory allocation method has good accuracy (positioning error <2%) and stability when operating a human-machine interface system.

  17. Deregulation of the lysyl hydroxylase matrix cross-linking system in experimental and clinical bronchopulmonary dysplasia.

    Science.gov (United States)

    Witsch, Thilo J; Turowski, Pawel; Sakkas, Elpidoforos; Niess, Gero; Becker, Simone; Herold, Susanne; Mayer, Konstantin; Vadász, István; Roberts, Jesse D; Seeger, Werner; Morty, Rory E

    2014-02-01

    Bronchopulmonary dysplasia (BPD) is a common and serious complication of premature birth, characterized by a pronounced arrest of alveolar development. The underlying pathophysiological mechanisms are poorly understood although perturbations to the maturation and remodeling of the extracellular matrix (ECM) are emerging as candidate disease pathomechanisms. In this study, the expression and regulation of three members of the lysyl hydroxylase family of ECM remodeling enzymes (Plod1, Plod2, and Plod3) in clinical BPD, as well as in an experimental animal model of BPD, were addressed. All three enzymes were localized to the septal walls in developing mouse lungs, with Plod1 also expressed in the vessel walls of the developing lung and Plod3 expressed uniquely at the base of developing septa. The expression of plod1, plod2, and plod3 was upregulated in the lungs of mouse pups exposed to 85% O2, an experimental animal model of BPD. Transforming growth factor (TGF)-β increased plod2 mRNA levels and activated the plod2 promoter in vitro in lung epithelial cells and in lung fibroblasts. Using in vivo neutralization of TGF-β signaling in the experimental animal model of BPD, TGF-β was identified as the regulator of aberrant plod2 expression. PLOD2 mRNA expression was also elevated in human neonates who died with BPD or at risk for BPD, compared with neonates matched for gestational age at birth or chronological age at death. These data point to potential roles for lysyl hydroxylases in normal lung development, as well as in perturbed late lung development associated with BPD. PMID:24285264

  18. Development of UO2/PuO2 dispersed in uranium matrix CERMET fuel system for fast reactors

    International Nuclear Information System (INIS)

    CERMET fuel with either PuO2 or enriched UO2 dispersed in uranium metal matrix has a strong potential of becoming a fuel for the liquid metal cooled fast breeder reactors (LMR’s). In fact it may act as a bridge between the advantages and disadvantages associated with the two extremes of fuel systems (i.e. ceramic fuel and metallic fuel) for fast reactors. At Bhabha Atomic Research Centre (BARC), R and D efforts are on to develop this CERMET fuel by powder metallurgy route. This paper describes the development of flow sheet for preparation of UO2 dispersed in uranium metal matrix pellets for three different compositions i.e. U–20 wt%UO2, U–25 wt%UO2 and U–30 wt%UO2. It was found that the sintered pellets were having excellent integrity and their linear mass was higher than that of carbide fuel pellets used in Fast Breeder Test Reactor programme (FBTR) in India. The pellets were characterized by X-ray diffraction (XRD) technique for phase analysis and lattice parameter determination. The optical microstructures were developed and reported for all the three different U–UO2 compositions.

  19. Quasi-disjoint pentadiagonal matrix systems for the parallelization of compact finite-difference schemes and filters

    Science.gov (United States)

    Kim, Jae Wook

    2013-05-01

    This paper proposes a novel systematic approach for the parallelization of pentadiagonal compact finite-difference schemes and filters based on domain decomposition. The proposed approach allows a pentadiagonal banded matrix system to be split into quasi-disjoint subsystems by using a linear-algebraic transformation technique. As a result the inversion of pentadiagonal matrices can be implemented within each subdomain in an independent manner subject to a conventional halo-exchange process. The proposed matrix transformation leads to new subdomain boundary (SB) compact schemes and filters that require three halo terms to exchange with neighboring subdomains. The internode communication overhead in the present approach is equivalent to that of standard explicit schemes and filters based on seven-point discretization stencils. The new SB compact schemes and filters demand additional arithmetic operations compared to the original serial ones. However, it is shown that the additional cost becomes sufficiently low by choosing optimal sizes of their discretization stencils. Compared to earlier published results, the proposed SB compact schemes and filters successfully reduce parallelization artifacts arising from subdomain boundaries to a level sufficiently negligible for sophisticated aeroacoustic simulations without degrading parallel efficiency. The overall performance and parallel efficiency of the proposed approach are demonstrated by stringent benchmark tests.

  20. Matrix calculus

    CERN Document Server

    Bodewig, E

    1959-01-01

    Matrix Calculus, Second Revised and Enlarged Edition focuses on systematic calculation with the building blocks of a matrix and rows and columns, shunning the use of individual elements. The publication first offers information on vectors, matrices, further applications, measures of the magnitude of a matrix, and forms. The text then examines eigenvalues and exact solutions, including the characteristic equation, eigenrows, extremum properties of the eigenvalues, bounds for the eigenvalues, elementary divisors, and bounds for the determinant. The text ponders on approximate solutions, as well

  1. ADVANCES IN TRANSFER MATRIX METHOD FOR MULTIBODY SYSTEM DYNAMICS%多体系统传递矩阵法研究进展

    Institute of Scientific and Technical Information of China (English)

    芮筱亭; 戎保

    2012-01-01

    作为一种多体系统动力学新方法,多体系统传递矩阵法由于其无需系统总体动力学方程和快速计算的特点,已被广泛用于各种多管火箭、自行火炮、舰炮等复杂大型机械系统动力学分析与设计.本文介绍了该方法的研究进展,包括:线性多体系统传递矩阵法、多体系统离散时间传递矩阵法、二维系统传递矩阵法、受控多体系统传递矩阵法、多体系统传递矩阵法和通常动力学方法的混合方法等,给出了该方法解决自行火炮、多管火箭武器多体系统动力学的重大工程应用实例.%As a new method of multibody system dynamics, the transfer matrix method of multibody system has the following characteristics: without the global dynamics equation of system, low order of matrix involved, high efficiency. It has been widely used in the dynamic design of many complex mechanical systems, such as multiple launch rocket system, self-propelled artillery system, and warship gun system. In this paper, the advances in transfer matrix method of multibody system, including linear transfer matrix method of multibody system, discrete time transfer matrix method of multibody system, transfer matrix method of two-dimension system, transfer matrix method of controlled multibody system, and the mixed method of transfer matrix method of multibody system and ordinary dynamics methods, are presented. Some engineering applications of this method on self-propelled artillery system and multiple launch rocket system are also given.

  2. Time rate collision matrix

    International Nuclear Information System (INIS)

    The collision integral terms in Boltzmann equation are reformulated numerically leading to the substitution of the multiple integrals with a multiplicative matrix of the two colliding species velocity distribution functions which varies with the differential collision cross section. A matrix of lower rank may be constructed when one of the distribution functions is specified, in which case the matrix elements represent kinetic transition probabilities in the velocity space and the multiplication of the time rate collision matrix with the unknown velocity distribution function expresses the time rate of change of the distribution. The collision matrix may be used to describe the time evolution of systems in nonequilibrium conditions, to evaluate the rate of momentum and energy transfer between given species, or to generate validity criteria for linearized kinetic equations

  3. Anisotropic dielectric properties of two-dimensional matrix in pseudo-spin ferroelectric system

    Science.gov (United States)

    Kim, Se-Hun

    2016-10-01

    The anisotropic dielectric properties of a two-dimensional (2D) ferroelectric system were studied using the statistical calculation of the pseudo-spin Ising Hamiltonian model. It is necessary to delay the time for measurements of the observable and the independence of the new spin configuration under Monte Carlo sampling, in which the thermal equilibrium state depends on the temperature and size of the system. The autocorrelation time constants of the normalized relaxation function were determined by taking temperature and 2D lattice size into account. We discuss the dielectric constants of a two-dimensional ferroelectric system by using the Metropolis method in view of the Slater-Takagi defect energies.

  4. Sinapinic acid-directed synthesis of gold nanoclusters and their application to quantitative matrix-assisted laser desorption/ionization mass spectrometry

    Science.gov (United States)

    Chen, Tzu-Heng; Yu, Cheng-Ju; Tseng, Wei-Lung

    2014-01-01

    Core etching of gold nanoparticles (AuNPs) into smaller-sized clusters is a classic method for fabricating gold nanoclusters (AuNCs). The top down-based synthesis of AuNCs includes two steps: (i) reducing the Au3+ precursor solution to generate AuNPs in the presence of protecting ligands and (ii) core etching of the formed AuNPs into the AuNCs via ligand exchange. For the first time, this paper describes a one-step approach for preparing AuNCs using a top down approach. The sinapinic acid (SA)-induced formation of the AuNCs involved a three-step reaction process. First, large AuNPs (>200 nm) were quickly formed after mixing SA and the Au3+ precursor solution. Second, excess SA molecules self-assembled on the NP surface, and large AuNPs were etched to small AuNPs via electrostatic repulsion between the neighboring SA molecules. Finally, SA-induced core etching of the AuNPs resulted in the formation of the AuNCs within 70 min. Furthermore, we showed that the presence of the AuNCs in SA was capable of suppressing crystal growth and eliminating the coffee-ring effect. Thus, proteins can be successfully quantified using the SA-AuNCs as matrices for matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Compared with using SA as matrices, the SA-AuNCs offered substantial advantages for improving shot-to-shot reproducibility and enhancing the ionization efficiency of proteins.Core etching of gold nanoparticles (AuNPs) into smaller-sized clusters is a classic method for fabricating gold nanoclusters (AuNCs). The top down-based synthesis of AuNCs includes two steps: (i) reducing the Au3+ precursor solution to generate AuNPs in the presence of protecting ligands and (ii) core etching of the formed AuNPs into the AuNCs via ligand exchange. For the first time, this paper describes a one-step approach for preparing AuNCs using a top down approach. The sinapinic acid (SA)-induced formation of the AuNCs involved a three-step reaction process. First, large

  5. The Usefulness of Performance Matrix Tests in Locomotor System Evaluation of Girls Attending a Ballet School — Preliminary Observation

    Science.gov (United States)

    Wójcik, Małgorzata; Siatkowski, Idzi

    2014-01-01

    [Purpose] Learning ballet is connected with continuous use of the locomotor system while subjecting it to high loads. Therefore, we conducted some research defining the appearance of weak links in the motor system, in order to eliminate the risk of injury. [Methods] Fifty-two female students of a ballet school were examined. To identify weak links, low-threshold Performance Matrix tests were performed. An analysis of weak link occurrence in the locomotor system was carried out, using two way analysis of variance ANOVA Tukey’s HSD test, clustering methods and Principal Component Analysis (PCA). [Results] The average age of the subjects was 11.64±0.53 years (mean ± standard deviation), their average body height was 151.1±7.5 cm, their average body weight was 35.92±5.41 kg, and their average time of learning at ballet school was 2.17±0.65 years. We found that there were significant differences in weak links occurrence in the motor system of every girl examined. [Conclusions] Weak links were found in every location of the motor system. Our results show that the influence of weak link location is essentially different from their occurrence, and that learning ballet has a significantly different impact on the number of weak links in different locations. PMID:24567673

  6. The usefulness of performance matrix tests in locomotor system evaluation of girls attending a ballet school - preliminary observation.

    Science.gov (United States)

    Wójcik, Małgorzata; Siatkowski, Idzi

    2014-01-01

    [Purpose] Learning ballet is connected with continuous use of the locomotor system while subjecting it to high loads. Therefore, we conducted some research defining the appearance of weak links in the motor system, in order to eliminate the risk of injury. [Methods] Fifty-two female students of a ballet school were examined. To identify weak links, low-threshold Performance Matrix tests were performed. An analysis of weak link occurrence in the locomotor system was carried out, using two way analysis of variance ANOVA Tukey's HSD test, clustering methods and Principal Component Analysis (PCA). [Results] The average age of the subjects was 11.64±0.53 years (mean ± standard deviation), their average body height was 151.1±7.5 cm, their average body weight was 35.92±5.41 kg, and their average time of learning at ballet school was 2.17±0.65 years. We found that there were significant differences in weak links occurrence in the motor system of every girl examined. [Conclusions] Weak links were found in every location of the motor system. Our results show that the influence of weak link location is essentially different from their occurrence, and that learning ballet has a significantly different impact on the number of weak links in different locations. PMID:24567673

  7. Gamma Matrix Expansion of the Bethe-Salpeter Equation for Nucleon-Nucleon System

    CERN Document Server

    Kinpara, Susumu

    2016-01-01

    For the coefficients of the amplitude a set of simultaneous equations is derived in momentum space. By the auxiliary conditions they are equivalent to nonrelativistic equations and suitable for the investigation of two-nucleon system.

  8. The Effects of Crack on the Transmission Matrix of Rotor Systems

    Directory of Open Access Journals (Sweden)

    Z.K. Peng

    2011-01-01

    Full Text Available The dynamic behavior of rotor containing crack is a subject of particular interest and has been extensively investigated by researchers. The effects of crack on the natural frequencies and modal shapes and motion orbits of rotor systems have already been well explored by researchers. In the present study, the infl uence of crack on the transmission matrices of the rotor systems is investigated by using the FEM (finite element method analysis and the HBM (harmonic balance method technique. It is for the first time revealed that there are differences between the transmission matrices for the fundamental frequency components and the transmission matrices for the super-harmonic components, and the differences are mainly determined by the crack location. The results are validated by numerical experiments where the system responses of a rotor system are obtained using Runge-Kutta method. The results are of significance for the development of effective crack detection methods in practice.

  9. Salvianolic Acid B Down-regulates Matrix Metalloproteinase-9 Activity and Expression in Tumor Necrosis Factor-α-induced Human Coronary Artery Endothelial Cells

    Institute of Scientific and Technical Information of China (English)

    Le Ma; Yun-Qian Guan; Zhong-Dong Du

    2015-01-01

    Background:Salvianolic acid B (Sal B) is a bioactive water-soluble compound of Salviae miltiorrhizae,a traditional herbal medicine that has been used clinically tor the treatment of cardiovascular diseases.This study sought to evaluate the effect of Sal B on matrix metalloproteinase-9 (MMP-9) and on the underlying mechanisms in tumor necrosis factor-α (TNF-α)-activated human coronary artery endothelial cells (HCAECs),a cell model of Kawasaki disease.Methods:HCAECs were pretreated with 1 l0 μmol/L of Sal B,and then stimulated by TNF-α at different time points.The protein expression and activity of MMP-9 were determined by Western blot assay and gelatin zymogram assay,respectively.Nuclear factor-κB (NF-κB) activation was detected with immunofluorescence,electrophoretic mobility shift assay,and Western blot assay.Protein expression levels of mitogen-activated protein kinase (c-Jun N-terminal kinase [JNK],extra-cellular signal-regulated kinase [ERK],and p38) were determined by Western blot assay.Results:After HCAECs were exposed to TNF-α,1-10 μtmol/L Sal B significantly inhibited TNF-α-induced MMP-9 expression and activity.Furthermore,Sal B significantly decreased IκBα phosphorylation and p65 nuclear translocation in HCAECs stimulated with TNF-α for 30 min.In addition,Sal B decreased the phosphorylation of JNK and ERK1/2 proteins in cells treated with TNF-α for 10 min.Conclusions:The data suggested that Sal B suppressed TNF-α-induced MMP-9 expression and activity by blocking the activation of NF-κB,JNK,and ERK1/2 signaling pathways.

  10. Sinapinic acid-directed synthesis of gold nanoclusters and their application to quantitative matrix-assisted laser desorption/ionization mass spectrometry.

    Science.gov (United States)

    Chen, Tzu-Heng; Yu, Cheng-Ju; Tseng, Wei-Lung

    2014-01-01

    Core etching of gold nanoparticles (AuNPs) into smaller-sized clusters is a classic method for fabricating gold nanoclusters (AuNCs). The top down-based synthesis of AuNCs includes two steps: (i) reducing the Au(3+) precursor solution to generate AuNPs in the presence of protecting ligands and (ii) core etching of the formed AuNPs into the AuNCs via ligand exchange. For the first time, this paper describes a one-step approach for preparing AuNCs using a top down approach. The sinapinic acid (SA)-induced formation of the AuNCs involved a three-step reaction process. First, large AuNPs (>200 nm) were quickly formed after mixing SA and the Au(3+) precursor solution. Second, excess SA molecules self-assembled on the NP surface, and large AuNPs were etched to small AuNPs via electrostatic repulsion between the neighboring SA molecules. Finally, SA-induced core etching of the AuNPs resulted in the formation of the AuNCs within 70 min. Furthermore, we showed that the presence of the AuNCs in SA was capable of suppressing crystal growth and eliminating the coffee-ring effect. Thus, proteins can be successfully quantified using the SA-AuNCs as matrices for matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Compared with using SA as matrices, the SA-AuNCs offered substantial advantages for improving shot-to-shot reproducibility and enhancing the ionization efficiency of proteins. PMID:24288017

  11. All-trans retinoic acid regulates the expression of the extracellular matrix protein fibulin-1 in the guinea pig sclera and human scleral fibroblasts

    Science.gov (United States)

    Li, Chuanxu; McFadden, Sally A.; Morgan, Ian; Cui, Dongmei; Hu, Jianmin; Wan, Wenjuan

    2010-01-01

    Purpose Fibulin-1 (FBLN1) mRNA is expressed in human sclera and is an important adhesion modulatory protein that can affect cell–matrix interactions and tissue remodeling. Scleral remodeling is influenced by all-trans retinoic acid (RA). Our purpose was to confirm the presence of fibulin-1 protein in guinea pig sclera and investigate the effect of RA on the expression of fibulin-1 in guinea pig sclera in vivo and in cultured human scleral fibroblasts (HSFs). Methods Confocal fluorescence microscopy was used to study fibulin-1 and aggrecan expression and localization in sclera from control guinea pigs and in animals given RA by daily gavage from 4 to 8 days of age. The effects of RA (from 10−9 to 10−5 M) on fibulin-1 expression in HSFs were observed by immunohistochemistry and assayed by real-time PCR and western blot analysis. Results Fibulin-1 protein expression was detected by confocal fluorescence microscopy in guinea pig sclera and in cultured HSFs. Upregulation of fibulin-1 in scleral tissue was observed after feeding with RA. In vitro, the level of Fbln1 mRNA was increased after treatment of HSFs with RA (at concentrations of 10−8 to 10−6 M; p<0.001), with a maximum effect at 10−7 M. Fibulin-1 protein levels were significantly increased after treatment of HSFs with 10−7 M of RA for 24 or 48 h (p<0.05). Conclusions Fibulin-1 protein was expressed in guinea pig sclera and cultured HSFs. Expression was regulated by RA, a molecule known to be involved in the regulation of eye growth. Further studies on the role of fibulin-1 in the regulation of eye growth, including during the development of myopia, are therefore warranted. PMID:20405022

  12. Comparison of cellular effects of starch-coated SPIONs and poly(lactic-co-glycolic acid) matrix nanoparticles on human monocytes

    Science.gov (United States)

    Gonnissen, Dominik; Qu, Ying; Langer, Klaus; Öztürk, Cengiz; Zhao, Yuliang; Chen, Chunying; Seebohm, Guiscard; Düfer, Martina; Fuchs, Harald; Galla, Hans-Joachim; Riehemann, Kristina

    2016-01-01

    Within the last years, progress has been made in the knowledge of the properties of medically used nanoparticles and their toxic effects, but still, little is known about their influence on cellular processes of immune cells. The aim of our comparative study was to present the influence of two different nanoparticle types on subcellular processes of primary monocytes and the leukemic monocyte cell line MM6. We used core-shell starch-coated superparamagnetic iron oxide nanoparticles (SPIONs) and matrix poly(lactic-co-glycolic acid) (PLGA) nanoparticles for our experiments. In addition to typical biocompatibility testing like the detection of necrosis or secretion of interleukins (ILs), we investigated the impact of these nanoparticles on the actin cytoskeleton and the two voltage-gated potassium channels Kv1.3 and Kv7.1. Induction of necrosis was not seen for PLGA nanoparticles and SPIONs in primary monocytes and MM6 cells. Likewise, no alteration in secretion of IL-1β and IL-10 was detected under the same experimental conditions. In contrast, IL-6 secretion was exclusively downregulated in primary monocytes after contact with both nanoparticles. Two-electrode voltage clamp experiments revealed that both nanoparticles reduce currents of the aforementioned potassium channels. The two nanoparticles differed significantly in their impact on the actin cytoskeleton, demonstrated via atomic force microscopy elasticity measurement and phalloidin staining. While SPIONs led to the disruption of the respective cytoskeleton, PLGA did not show any influence in both experimental setups. The difference in the effects on ion channels and the actin cytoskeleton suggests that nanoparticles affect these subcellular components via different pathways. Our data indicate that the alteration of the cytoskeleton and the effect on ion channels are new parameters that describe the influence of nanoparticles on cells. The results are highly relevant for medical application and further

  13. Solving systems of linear equations by GPU-based matrix factorization in a Science Ground Segment

    Science.gov (United States)

    Legendre, Maxime; Schmidt, Albrecht; Moussaoui, Saïd; Lammers, Uwe

    2013-11-01

    Recently, Graphics Cards have been used to offload scientific computations from traditional CPUs for greater efficiency. This paper investigates the adaptation of a real-world linear system solver, which plays a central role in the data processing of the Science Ground Segment of ESA's astrometric Gaia mission. The paper quantifies the resource trade-offs between traditional CPU implementations and modern CUDA based GPU implementations. It also analyses the impact on the pipeline architecture and system development. The investigation starts from both a selected baseline algorithm with a reference implementation and a traditional linear system solver and then explores various modifications to control flow and data layout to achieve higher resource efficiency. It turns out that with the current state of the art, the modifications impact non-technical system attributes. For example, the control flow of the original modified Cholesky transform is modified so that locality of the code and verifiability deteriorate. The maintainability of the system is affected as well. On the system level, users will have to deal with more complex configuration control and testing procedures.

  14. Preparation and evaluation of microemulsion systems containing salicylic acid.

    Science.gov (United States)

    Badawi, Alia A; Nour, Samia A; Sakran, Wedad S; El-Mancy, Shereen Mohamed Sameh

    2009-01-01

    Microemulsions (MEs) are clear, thermodynamically stable systems. They were used to solubilize drugs and to improve topical drug availability. Salicylic acid (SA) is a keratolytic agent used in topical products with antimicrobial actions. The objective of this work was to prepare and evaluate SA ME systems. Different concentrations of SA were incorporated in an ME base composed of isopropyl myristate, water, and Tween 80: propylene glycol in the ratio of 15:1. Three ME systems were prepared: S2%, S5%, and S10% which contain 2%, 5%, and 10% of SA, respectively. Evaluation by examination under cross-polarizing microscope, measuring of percent transmittance, pH measurement, determination of the specific gravity, assessment of rheological properties, and accelerated stability study were carried out. The data showed that the addition of SA markedly affected the physical properties of the base. All systems were not affected by accelerated stability tests. Stability study for 6 months under ambient conditions was carried out for S10%. No remarkable changes were recorded except a decrease in the viscosity value after 1 month. The results suggested that ME could be a suitable vehicle for topical application of different concentrations of SA. PMID:19757081

  15. THE STABILIZATION SYSTEM OF SOIL ACIDITY WHEN GROWING TOMATOES IN A GREENHOUSE

    Directory of Open Access Journals (Sweden)

    Tsokur D. S.

    2013-11-01

    Full Text Available The article presents: the stabilization system of soil acidity, which allows subsoil irrigation tomato plants catholyte to compensate the negative effects of acidic fertilizer, and additionally to prevent plant diseases anolyte solution; transfer function of the stabilization system of soil acidity and the results of its tests

  16. Microgravity effects on water supply and substrate properties in porous matrix root support systems

    Science.gov (United States)

    Bingham, G. E.; Jones, S. B.; Or, D.; Podolski, I. G.; Levinskikh, M. A.; Sytchov, V. N.; Ivanova, T.; Kostov, P.; Sapunova, S.; Dandolov, I.; Bubenheim, D. B.; Jahns, G.; Campbell, W. F. (Principal Investigator)

    2000-01-01

    The control of water content and water movement in granular substrate-based plant root systems in microgravity is a complex problem. Improper water and oxygen delivery to plant roots has delayed studies of the effects of microgravity on plant development and the use of plants in physical and mental life support systems. Our international effort (USA, Russia and Bulgaria) has upgraded the plant growth facilities on the Mir Orbital Station (OS) and used them to study the full life cycle of plants. The Bulgarian-Russian-developed Svet Space Greenhouse (SG) system was upgraded on the Mir OS in 1996. The US developed Gas Exchange Measurement System (GEMS) greatly extends the range of environmental parameters monitored. The Svet-GEMS complex was used to grow a fully developed wheat crop during 1996. The growth rate and development of these plants compared well with earth grown plants indicating that the root zone water and oxygen stresses that have limited plant development in previous long-duration experiments have been overcome. However, management of the root environment during this experiment involved several significant changes in control settings as the relationship between the water delivery system, water status sensors, and the substrate changed during the growth cycles. c 2001 Published by Elsevier Science Ltd. All rights reserved.

  17. Asymptotic degeneracy of the transfer matrix spectrum for systems with interfaces: Relation to surface stiffness and step free energy

    Energy Technology Data Exchange (ETDEWEB)

    Privman, V.; Svrakic, N.M.

    1989-02-01

    Two- and three-dimensional Ising-type systems are considered in the finite-cross-section cylindrical geometry. An interface is forced along the cylinder (strip in 2d) by the antiperiodic or /plus minus/ boundary conditions. Detailed predictions are presented for the largest asymptotically degenerate set of the transfer matrix eigenvalues. For rough interfaces, i.e., for O < T < T/sub c/ in 2d, T/sub R/ < T < T/sub c/ in 3d, the eigenvalues are split algebraically, and the spectral gaps are governed by the surface stiffness coefficient. For rigid interfaces, i.e., O < T < T /sub R/ in 3d, the eigenvalues are split exponentially, with the gaps determined by the step free energy.

  18. Estimation of Circular Error Probability of Strapped Down Inertial Navigation System by Propagation of Error Covariance Matrix

    Directory of Open Access Journals (Sweden)

    S. Vathsal

    1994-01-01

    Full Text Available This paper provides an error model of the strapped down inertial navigation system in the state space format. A method to estimate the circular error probability is presented using time propagation of error covariance matrix. Numerical results have been obtained for a typical flight trajectory. Sensitivity studies have also been conducted for variation of sensor noise covariances and initial state uncertainty. This methodology seems to work in all the practical cases considered so far. Software has been tested for both the local vertical frame and the inertial frame. The covariance propagation technique provides accurate estimation of dispersions of position at impact. This in turn enables to estimate the circular error probability (CEP very accurately.

  19. 武器装备体系能力矩阵评估方法%Matrix Methodology Based Capability Evaluation of Weapon System of Systems

    Institute of Scientific and Technical Information of China (English)

    曹强; 荆涛; 周少平

    2016-01-01

    针对武器装备体系能力难以客观、定量评估的问题,引入复杂网络理论,提出了基于矩阵运算的武器装备体系能力评估方法。分析了武器装备体系能力的概念,建立了武器装备体系的复杂层次网络模型,描述了装备网络的组成、运行过程,定义了装备网络的矩阵描述方法和矩阵运算规则,提出了装备网络作战能力描述参数,给出了装备网络能力的矩阵计算方法,进行了影响因素分析,最后通过实例验证了方法可行性、有效性和灵活性。%In order to evaluate capability of weapon system of systems more objectively and quantitively,complex networks theory is introduced,and a new matrix capability evaluation methodology is put forward. The capability definitions of weapon system of systems are analyzed,a layered complex network model of weapon system of systems is built,the components and operation process of the weapon network model are also described. Then matrix expression methods of weapon network and its special calculate rules are defined,tailor-made operation capability indexes of weapon network are brought out. The algorithm of using single-layer-matrixes and inter-layer-matrixes to compute whole weapon network’s capability is present; the influence factors of the algorithm are detailly analyzed. By the case study of a nominal operation network,the feasibility,validity and flexibility of proposed methodology are proved.

  20. An exact dynamic stiffness matrix for axially loaded double-beam systems

    Indian Academy of Sciences (India)

    Li Xiaobin; Xu Shuangxi; Wu Weiguo; Li Jun

    2014-06-01

    An exact dynamic stiffness method is presented in this paper to determine the natural frequencies and mode shapes of the axially loaded double-beam systems,which consist of two homogeneous and prismatic beams with a distributed spring in parallel between them.The effects of the axial force, shear deformation and rotary inertia are considered, as shown in the theoretical formulation. The dynamic stiffness influence coefficients are formulated from the governing differential equations of the axially loaded double-beam system in free vibration by using the Laplace transform method. An example is given to demonstrate the effectiveness of this method, in which ten boundary conditions are investigated and the effect of the axial force on the natural frequencies and mode shapes of the double-beam system are further discussed.

  1. Matrix equation decomposition and parallel solution of systems resulting from unstructured finite element problems in electromagnetics

    Energy Technology Data Exchange (ETDEWEB)

    Cwik, T. [California Institute of Technology, Pasadena, CA (United States); Katz, D.S. [Cray Research, El Segundo, CA (United States)

    1996-12-31

    Finite element modeling has proven useful for accurately simulating scattered or radiated electromagnetic fields from complex three-dimensional objects whose geometry varies on the scale of a fraction of an electrical wavelength. An unstructured finite element model of realistic objects leads to a large, sparse, system of equations that needs to be solved efficiently with regard to machine memory and execution time. Both factorization and iterative solvers can be used to produce solutions to these systems of equations. Factorization leads to high memory requirements that limit the electrical problem size of three-dimensional objects that can be modeled. An iterative solver can be used to efficiently solve the system without excessive memory use and in a minimal amount of time if the convergence rate is controlled.

  2. Weighted Moore–Penrose generalized matrix inverse: MySQL vs. Cassandra database storage system

    Indian Academy of Sciences (India)

    DANIJELA MILOSEVIC; SELVER PEPIC; MUZAFER SARACEVIC; MILAN TASIC

    2016-08-01

    The research in this paper refers to two areas: programming and data storage (data base) for computing the weighted Moore–Penrose inverse. The main aim of this paper analysis of the execution speed of computing using PHP programming language and data store. The research shows that the speed of execution gives considerable difference between the Procedural programming and Object Oriented PHP language, on the middle layer in the three tier of the web architecture. Also, the research concerning the comparison of relationdatabase system, MySQL and NoSQL, key value store system, ApacheCassandra, on the database layer. The CPU times are compared and discussed.

  3. Optimal observation for cyber-physical systems a fisher-information-matrix-based approach

    CERN Document Server

    Song, Zhen; Sastry, Chellury R; Tas, Nazif C

    2009-01-01

    Presents a framework within which many problems can be solved without resort to a combination of different methodsGives the reader access to a co-ordinated body of theoretical and applied research on the increasingly well-studied subject of cyber-physical systems

  4. Reduction of Under-Determined Linear Systems by Sparce Block Matrix Technique

    DEFF Research Database (Denmark)

    Tarp-Johansen, Niels Jacob; Poulsen, Peter Noe; Damkilde, Lars

    1996-01-01

    Under-determined linear equation systems occur in different engineering applications. In structural engineering they typically appear when applying the force method. As an example one could mention limit load analysis based on The Lower Bound Theorem. In this application there is a set of under...

  5. Solid-state active switch matrix for high energy, moderate power battery systems

    Science.gov (United States)

    Deal, Larry; Paris, Peter; Ye, Changqing

    2016-06-07

    A battery management system employs electronic switches and capacitors. No traditional cell-balancing resistors are used. The BMS electronically switches individual cells into and out of a module of cells in order to use the maximum amount of energy available in each cell and to completely charge and discharge each cell without overcharging or under-discharging.

  6. The 300 area waste acid treatment system closure plan

    International Nuclear Information System (INIS)

    The 300 Area Waste Acid Treatment System (WATS) is located within operable units 300-FF-2 (source) and 300-FF-5 (groundwater), as designated in the Hanford Federal Facility Agreement and Consent Order (Tri-Party Agreement) . Operable units 300-FF-2 and 300-FF-5 are scheduled to be remediated using the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) Remedial Investigation/Feasibility Study (RI/FS) process. Thus, any remediation of the 300 Area WATS with respect to contaminants not produced by those facilities and soils and groundwater will be deferred to the CERCLA RI/FS process. Final closure activities will be completed in 3 phases and certified in accordance with the 300 Area WATS closure plan by the Washington State Department of Ecology (Ecology) and the U.S. Environmental Protection Agency (EPA). It is anticipated that the 300 Area WATS closure would take 2 years to complete

  7. Development of PNA-Surfactant Systems for Nucleic Acid Separations

    Science.gov (United States)

    Vernille, James; Armitage, Bruce; Schneider, James

    2002-03-01

    We have been exploring the use of novel peptide nucleic acid (PNA) surfactants for use in sequence specific, scalable DNA separations. While the synthetic and physical characteristics of PNA make it a useful molecule for bioseparations, PNA shows limited water solubility. Here we describe a molecular design strategy to improve water solubility while maintaining sequence specificity. A candidate molecule has been identified which contains lysine residues and a short alkane tail. Melting temperature data show that lipid tail interactions with the DNA nucleobases have a small but significant effect on stability while the added lysines stabilize the complex in an ionic strength dependent way. We also discuss the incorporation of these surfactants into micellar systems for novel separations.

  8. Enzymatically triggered multifunctional delivery system based on hyaluronic acid micelles

    KAUST Repository

    Deng, Lin

    2012-01-01

    Tumor targetability and stimuli responsivity of drug delivery systems (DDS) are key factors in cancer therapy. Implementation of multifunctional DDS can afford targetability and responsivity at the same time. Herein, cholesterol molecules (Ch) were coupled to hyaluronic acid (HA) backbones to afford amphiphilic conjugates that can self-assemble into stable micelles. Doxorubicin (DOX), an anticancer drug, and superparamagnetic iron oxide (SPIO) nanoparticles (NPs), magnetic resonance imaging (MRI) contrast agents, were encapsulated by Ch-HA micelles and were selectively released in the presence of hyaluronidase (Hyals) enzyme. Cytotoxicity and cell uptake studies were done using three cancer cell lines (HeLa, HepG2 and MCF7) and one normal cell line (WI38). Higher Ch-HA micelles uptake was seen in cancer cells versus normal cells. Consequently, DOX release was elevated in cancer cells causing higher cytotoxicity and enhanced cell death. © 2012 The Royal Society of Chemistry.

  9. Efficient Debromination of Vicinal (, (-Dibromo Carboxylic Acid Derivatives with the Sm/HOAc System

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The α, β vicinal dibromo carboxylic acid and its derivatives were debrominated with Sm/HOAc system to afford the corresponding cinnamic acid and its derivatives in good yields under mild conditions.

  10. A novel gastro-floating multiparticulate system for dipyridamole (DIP) based on a porous and low-density matrix core: in vitro and in vivo evaluation.

    Science.gov (United States)

    Li, Zhao; Xu, Heming; Li, Shujuan; Li, Qijun; Zhang, Wenji; Ye, Tiantian; Yang, Xinggang; Pan, Weisan

    2014-01-30

    The study was aimed to develop a novel gastro-floating multiparticulate system based on a porous and low-density matrix core with excellent floatability. The gastro-floating pellets (GFP) were composed of a porous matrix core, a drug loaded layer (DIP and HPMC), a sub-coating layer (HPMC) and a retarding layer (Eudragit(®) NE 30D). The porous matrix cores were evaluated in specific. EC was chosen as the matrix membrane for its rigidity and minimal expansion to large extent. The porous matrix core was achieved by the complete release of the bulk water soluble excipient from the EC coated beads, and mannitol was selected as the optimal water soluble excipient. SEM photomicrographs confirmed the structure of porous matrix cores. The compositions of GFP were investigated and optimized by orthogonal array design. The optimized formulation could sustain the drug release for 12h and float on the dissolution medium for at least 12h without lag time to float. The pharmacokinetic study was conducted in beagle dogs, and the relative bioavailability of the test preparation was 193.11±3.43%. In conclusion, the novel gastro-floating pellets can be developed as a promising approach for the gastro-retentive drug delivery systems.

  11. A novel gastro-floating multiparticulate system for dipyridamole (DIP) based on a porous and low-density matrix core: in vitro and in vivo evaluation.

    Science.gov (United States)

    Li, Zhao; Xu, Heming; Li, Shujuan; Li, Qijun; Zhang, Wenji; Ye, Tiantian; Yang, Xinggang; Pan, Weisan

    2014-01-30

    The study was aimed to develop a novel gastro-floating multiparticulate system based on a porous and low-density matrix core with excellent floatability. The gastro-floating pellets (GFP) were composed of a porous matrix core, a drug loaded layer (DIP and HPMC), a sub-coating layer (HPMC) and a retarding layer (Eudragit(®) NE 30D). The porous matrix cores were evaluated in specific. EC was chosen as the matrix membrane for its rigidity and minimal expansion to large extent. The porous matrix core was achieved by the complete release of the bulk water soluble excipient from the EC coated beads, and mannitol was selected as the optimal water soluble excipient. SEM photomicrographs confirmed the structure of porous matrix cores. The compositions of GFP were investigated and optimized by orthogonal array design. The optimized formulation could sustain the drug release for 12h and float on the dissolution medium for at least 12h without lag time to float. The pharmacokinetic study was conducted in beagle dogs, and the relative bioavailability of the test preparation was 193.11±3.43%. In conclusion, the novel gastro-floating pellets can be developed as a promising approach for the gastro-retentive drug delivery systems. PMID:24368104

  12. Glutamic acid modified fenton system for degradation of BTEX contamination

    Energy Technology Data Exchange (ETDEWEB)

    Yehia, Fatma Z.; Badawi, Abdelfatah M.; Mady, Amr H. [Department of Petrochemicals, Egyptian Petroleum Research Institute, Nasr City, Cairo (Egypt); Kandile, Nadia G. [Faculty of Women, Department of Chemistry, Ain Shams University, Heliopolis, Cairo (Egypt)

    2012-07-15

    The present study employed a modified Fenton system that aims to extend the optimum pH range towards neutral conditions for studying the oxidation of benzene, toluene, ethyl benzene, xylenes (BTEX) using glutamic acid (Glu) as an iron chelator. Addition of 20 mM Glu greatly enhanced the oxidation rate of BTEX in modified Fenton system at pH 5-7. A rapid mass destruction (>97% after 1 h) of BTEX as a water contaminant carried out in the presence of 500 mM H{sub 2}O{sub 2}, 10 mM Fe{sup 2+}, and 20 mM Glu at pH 5 could be shown. The efficiency of this modified Fenton's system for mass destruction of BTEX in contaminated water was measured to estimate the impact of the major process variables that include initial concentrations of soluble Fe, H{sub 2}O{sub 2}, Glu (as metal chelating agent), and reaction time. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  13. Excess molar enthalpies of binary systems containing 2-octanone, hexanoic acid, or octanoic acid at T = 298.15 K

    Energy Technology Data Exchange (ETDEWEB)

    Liao, Wei-Chen; Lin, Ho-mu [Department of Chemical Engineering, National Taiwan University of Science and Technology, 43 Keelung Road, Section 4, Taipei 106-07, Taiwan (China); Lee, Ming-Jer, E-mail: mjlee@mail.ntust.edu.tw [Department of Chemical Engineering, National Taiwan University of Science and Technology, 43 Keelung Road, Section 4, Taipei 106-07, Taiwan (China)

    2012-01-15

    Highlights: > An isothermal titration calorimeter was used for enthalpy data measurement. > The investigated binary systems contain 2-octanone, hexanoic acid, or octanoic acid. > The excess enthalpies are all positive except for mixtures containing DMSO and DMF. > The Peng-Robinson equation with two parameters yielded the best representation. - Abstract: An isothermal titration calorimeter was used to measure the excess molar enthalpies (H{sup E}) of six binary systems at T = 298.15 K under atmospheric pressure. The systems investigated include (1-hexanol + 2-octanone), (1-octanol + 2-octanone), (1-hexanol + octanoic acid), (1-hexanol + hexanoic acid), {l_brace}N,N-dimethylformamide (DMF) + hexanoic acid{r_brace}, and {l_brace}dimethyl sulfoxide (DMSO) + hexanoic acid{r_brace}. The values of excess molar enthalpies are all positive except for the DMSO- and the DMF-containing systems. In the 1-hexanol with hexanoic acid or octanoic acid systems, the maximum values of H{sup E} are located around the mole fraction of 0.4 of 1-hexanol, but the H{sup E} vary nearly symmetrically with composition for other four systems. In addition to the modified Redlich-Kister and the NRTL models, the Peng-Robinson (PR) and the Patel-Teja (PT) equations of state were used to correlate the excess molar enthalpy data. The modified Redlich-Kister equation correlates the H{sup E} data to within about experimental uncertainty. The calculated results from the PR and the PT are comparable. It is indicated that the overall average absolute relative deviations (AARD) of the excess enthalpy calculations are reduced from 18.8% and 18.8% to 6.6% and 7.0%, respectively, as the second adjustable binary interaction parameter, k{sub bij}, is added in the PR and the PT equations. Also, the NRTL model correlates the H{sup E} data to an overall AARD of 10.8% by using two adjustable model parameters.

  14. Stability, controllability and observability of linear matrix-second-order systems

    Science.gov (United States)

    Hughes, P. C.; Skelton, R. E.

    1979-01-01

    The stability, controllability and observability of lightly damped linear mechanical systems are considered and gyroscopic effects (e.g., control moment gyros) are also included. The structure of the equations is further specified to include both 'rigid' and 'elastic' modes, possibly coupled by gyroscopic terms. Stability and asymptotic stability results are summarized in two theorems. The special structure of the system equations permits a statement of the necessary and sufficient conditions for controllability and observability in terms of simple rank tests. Of great practical significance, the minimum number of actuators and sensors are among the necessary conditions derived. Natural definitions for modal controllability and observability are also evolved which give a direct indication of beneficial locations for actuators and sensors.

  15. Osmolarity affects matrix synthesis in the nucleus pulposus associated with the involvement of MAPK pathways: A study of ex vivo disc organ culture system.

    Science.gov (United States)

    Li, Pei; Gan, Yibo; Xu, Yuan; Li, Songtao; Song, Lei; Li, Sukai; Li, Huijuan; Zhou, Qiang

    2016-06-01

    Matrix homeostasis within the nucleus pulposus (NP) is important for disc function. Unfortunately, the effects of osmolarity on NP matrix synthesis in a disc organ culture system and the underlying mechanisms are largely unknown. The present study was to investigate the effects of different osmolarity modes (constant and cyclic) and osmolarity levels (hypo-, iso-, and hyper-) on NP matrix synthesis using a disc organ culture system and determine whether ERK1/2 or p38MAPK pathway has a role in this process. Porcine discs were cultured for 7 days in various osmotic media, including constant hypo-, iso-, hyper-osmolarity (330, 430, and 550 mOsm/kg, respectively) and cyclic-osmolarity (430 mOsm/kg for 8 h, followed by 550 mOsm/kg for 16 h). The role of ERK1/2 and p38MAPK pathways were determined by their inhibitors U0126 and SB202190 respectively. The expression of SOX9 and downstream aggrecan and collagen II, biochemical content, and histology were used to assess NP matrix synthesis. The findings revealed that NP matrix synthesis was promoted in iso- and cyclic-osmolarity cultures compared to hypo- or hyper-osmolarity culture although the level of matrix synthesis in cyclic-osmolarity culture did not reach that in iso-osmolarity culture. Further analysis suggested that inhibition of the ERK1/2 or p38MAPK pathway in iso- and cyclic-osmolarity cultures reduced NP matrix production. Therefore, we concluded that the effects of osmolarity on NP matrix synthesis depend on osmolarity level (hypo-, iso-, or hyper-) and osmolarity mode (constant or cyclic), and the ERK1/2 and p38MAPK pathways may participate in this process. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1092-1100, 2016.

  16. Omega-3 fatty acids differentially modulate enzymatic anti-oxidant systems in skeletal muscle cells

    OpenAIRE

    E. P. da Silva; Nachbar, R. T.; Levada-Pires, A. C.; Hirabara, S. M.; Lambertucci, R. H.

    2015-01-01

    During physical activity, increased reactive oxygen species production occurs, which can lead to cell damage and in a decline of individual’s performance and health. The use of omega-3 polyunsaturated fatty acids as a supplement to protect the immune system has been increasing; however, their possible benefit to the anti-oxidant system is not well described. Thus, the aim of this study was to evaluate whether the omega-3 fatty acids (docosahexaenoic acid and eicosapentaenoic acid) can be bene...

  17. Acetic Acid Production by an Electrodialysis Fermentation Method with a Computerized Control System

    OpenAIRE

    Nomura, Yoshiyuki; Iwahara, Masayoshi; Hongo, Motoyoshi

    1988-01-01

    In acetic acid fermentation by Acetobacter aceti, the acetic acid produced inhibits the production of acetic acid by this microorganism. To alleviate this inhibitory effect, we developed an electrodialysis fermentation method such that acetic acid is continuously removed from the broth. The fermentation unit has a computerized system for the control of the pH and the concentration of ethanol in the fermentation broth. The electrodialysis fermentation system resulted in improved cell growth an...

  18. Extracellular matrix of the central nervous system: from neglect to challenge

    OpenAIRE

    Zimmermann, D R; Dours-Zimmermann, M

    2008-01-01

    The basic concept, that specialized extracellular matrices rich in hyaluronan, chondroitin sulfate proteoglycans (aggrecan, versican, neurocan, brevican, phosphacan), link proteins and tenascins (Tn-R, Tn-C) can regulate cellular migration and axonal growth and thus, actively participate in the development and maturation of the nervous system, has in recent years gained rapidly expanding experimental support. The swift assembly and remodeling of these matrices have been associated with axonal...

  19. Construction Zero Cross Correlation Code using Permutation Matrix for SAC-OCDMA Systems

    OpenAIRE

    Nisar, K. S.

    2016-01-01

    This paper present a new method for constructing zero cross correlation code with the help of permutation matrices. The benefits of this newly proposed code are easy way code construction, the code weight exist for every natural number and the code length is acceptable. The numerical comparison shows that the proposed code has better or compatible code length compared with other existing zero cross correlation code in Optical Spectrum Code Division Multiple Access (OSCDMA) systems.

  20. Structure-Processing-Property Relationship of Poly(Glycolic Acid for Drug Delivery Systems 1: Synthesis and Catalysis

    Directory of Open Access Journals (Sweden)

    Vineet Singh

    2010-01-01

    Full Text Available Till date, market is augmented with a huge number of improved drug delivery systems. The success in this area is basically due to biodegradable polymers. Although conventional systems of drug delivery utilizing the natural and semisynthetic polymers so long but synthetic polymer gains success in the controlled drug delivery area due to better degradation profile and controlled network and functionality. The polyesters are the most studied class group due the susceptible ester linkage in their backbone. The Poly(glycolic Acid (PGA, Poly(lactic acid (PLA, and Polylactide-co-glycolide (PLGA are the best profiled polyesters and are most widely used in marketed products. These polymers, however, still are having drawbacks which failed them to be used in platform technologies like matrix systems, microspheres, and nanospheres in some cases. The common problems arose with these polymers are entrapment inefficiency, inability to degrade and release drugs with required profile, and drug instability in the microenvironment of the polymers. These problems are forcing us to develop new polymers with improved physicochemical properties. The present review gave us an insight in the various structural elements of Poly(glycolic acid, polyester, with in depth study. The first part of the review focuses on the result of studies related to synthetic methodologies and catalysts being utilized to synthesize the polyesters. However the author will also focus on the effect of processing methodologies but due some constraints those are not included in the preview of this part of review.

  1. Matrix Algebra for GPU and Multicore Architectures (MAGMA) for Large Petascale Systems

    Energy Technology Data Exchange (ETDEWEB)

    Dongarra, Jack J. [University Distinguished Professor; Tomov, Stanimire [Research Scientist

    2014-03-24

    The goal of the MAGMA project is to create a new generation of linear algebra libraries that achieve the fastest possible time to an accurate solution on hybrid Multicore+GPU-based systems, using all the processing power that future high-end systems can make available within given energy constraints. Our efforts at the University of Tennessee achieved the goals set in all of the five areas identified in the proposal: 1. Communication optimal algorithms; 2. Autotuning for GPU and hybrid processors; 3. Scheduling and memory management techniques for heterogeneity and scale; 4. Fault tolerance and robustness for large scale systems; 5. Building energy efficiency into software foundations. The University of Tennessee’s main contributions, as proposed, were the research and software development of new algorithms for hybrid multi/many-core CPUs and GPUs, as related to two-sided factorizations and complete eigenproblem solvers, hybrid BLAS, and energy efficiency for dense, as well as sparse, operations. Furthermore, as proposed, we investigated and experimented with various techniques targeting the five main areas outlined.

  2. Transient and stability analysis of large scale rotor-bearing system with strong nonlinear elements by the mode summation-transfer matrix method

    Science.gov (United States)

    Gu, Zhiping

    This paper extends Riccati transfer matrix method to the transient and stability analysis of large scale rotor-bearing systems with strong nonlinear elements, and proposes a mode summation-transfer matrix method, in which the field transfer matrix of a distributed mass uniform shaft segment is obtained with the aid of the idea of mode summation and Newmark beta formulation, and the Riccati transfer matrix method is adopted to stablize the boundary value problem of the nonlinear systems. In this investigation, the real nonlinearity of the strong nonlinear elements is considered, not linearized, and the advantages of the Riccati transfer matrix are retained. So, this method is especially applicable to analyze the transient response and stability of large-scale rotor-bear systems with strong nonlinear elements. One example, a single-spool rotating system with strong nonlinear elements, is given. The obtained results show that this method is superior to that of Gu and Chen (1990) in accuracy, stability, and economy.

  3. The ternary system U(VI) / humic acid / Opalinus Clay

    Energy Technology Data Exchange (ETDEWEB)

    Joseph, Claudia

    2013-07-23

    The storage of nuclear waste in deep geological formations is discussed worldwide as the main strategy for nuclear waste management. To ensure the confinement of the nuclear waste, a multiple barrier system which consists of engineered, geo-engineered, and geological barriers will be applied. Thereby, in Germany the definition of the isolating rock zone represents an important safety function indicator. Clay rock is internationally investigated as potential host rock for a repository and represents a part of the geological barrier. In the present work, the natural clay rock Opalinus Clay from the Mont Terri rock laboratory, Switzerland, was studied. In Germany, the direct disposal of the spent nuclear fuel without the reprocessing of the spent fuel is preferred. In case of water ingress, radionuclides can be released from the nuclear waste repository into its surroundings, namely the host rock of the repository. Humic acids, ubiquitous in nature, can be found associated with the inorganic components in natural clay rock (1.5 x 10{sup -3} wt.% in Opalinus Clay). They can be released under certain conditions. Due to their variety of functional groups, humic acids are very strong complexing agents for metal ions. They have inherent redox abilities and a colloidal conformation in solution. Because of these characteristics, humic acids can affect the mobility of metal ions such as actinides. Furthermore, in the near-field of a repository elevated temperatures have to be considered due to the heat production resulting from the radioactive decay of the various radionuclides in the nuclear waste. This work focuses on the interaction of uranium, as main component of spent nuclear fuel, with Opalinus Clay and studies the influence of humic acid and elevated temperature on this interaction. Thus, the collected sorption and diffusion data are not only relevant for safety assessment of nuclear waste repositories but also for any clay-containing system present in the environment

  4. Silica-based ionic liquid coating for 96-blade system for extraction of aminoacids from complex matrixes

    Energy Technology Data Exchange (ETDEWEB)

    Mousavi, Fatemeh; Pawliszyn, Janusz, E-mail: janusz@uwaterloo.ca

    2013-11-25

    Graphical abstract: -- Highlights: •Silica-based 1-vinyl-3-octadecylimidazolium bromide ionic liquid was synthesized and characterized. •The synthesized polymer was immobilized on the stainless steel blade using polyacrylonitrile glue. •SiImC{sub 18}-PAN 96-blade SPME was applied as an extraction phase for extraction of highly polar compounds in grape matrix. •This system provides high extraction efficiency and reproducibility for up to 50 extractions from tartaric buffer and 20 extractions from grape pulp. -- Abstract: 1-Vinyl-3-octadecylimidazolium bromide ionic liquid [C{sub 18}VIm]Br was prepared and used for the modification of mercaptopropyl-functionalized silica (Si-MPS) through surface radical chain-transfer addition. The synthesized octadecylimidazolium-modified silica (SiImC{sub 18}) was characterized by thermogravimetric analysis (TGA), infrared spectroscopy (IR), {sup 13}C NMR and {sup 29}Si NMR spectroscopy and used as an extraction phase for the automated 96-blade solid phase microextraction (SPME) system with thin-film geometry using polyacrylonitrile (PAN) glue. The new proposed extraction phase was applied for extraction of aminoacids from grape pulp, and LC–MS–MS method was developed for separation of model compounds. Extraction efficiency, reusability, linearity, limit of detection, limit of quantitation and matrix effect were evaluated. The whole process of sample preparation for the proposed method requires 270 min for 96 samples simultaneously (60 min preconditioning, 90 min extraction, 60 min desorption and 60 min for carryover step) using 96-blade SPME system. Inter-blade and intra-blade reproducibility were in the respective ranges of 5–13 and 3–10% relative standard deviation (RSD) for all model compounds. Limits of detection and quantitation of the proposed SPME-LC–MS/MS system for analysis of analytes were found to range from 0.1 to 1.0 and 0.5 to 3.0 μg L{sup −1}, respectively. Standard addition calibration was

  5. RESOURCE ALLOCATION TECHNIQUE USING LOAD MATRIX METHOD IN WIRELESS CELLULAR SYSTEMS

    Directory of Open Access Journals (Sweden)

    S.Prabhakar

    2012-05-01

    Full Text Available An efficient resource allocation is one of the greatest challenges in wireless cellular communication. The resource allocation schemes avoid wastage of resources by allocating resources to a mobile terminal over a short period of time, providing quality of service over wireless networks is the most stressing point for service providers. In general a high degree of sharing is efficient, but requires service protection mechanisms to guarantee the QoS for all services. In this paper we address the multi cell interference on overall radio resource utilization and propose a new strategy for resource allocation in multi cell systems. we also propose a joint management of interference within and between cells for allocation of radio resources , Simulation results are showing that there is a significant improvement in the resource utilization so that overall network performance.

  6. Matrix Thermalization

    CERN Document Server

    Craps, Ben; Nguyen, Kévin

    2016-01-01

    Matrix quantum mechanics offers an attractive environment for discussing gravitational holography, in which both sides of the holographic duality are well-defined. Similarly to higher-dimensional implementations of holography, collapsing shell solutions in the gravitational bulk correspond in this setting to thermalization processes in the dual quantum mechanical theory. We construct an explicit, fully nonlinear supergravity solution describing a generic collapsing dilaton shell, specify the holographic renormalization prescriptions necessary for computing the relevant boundary observables, and apply them to evaluating thermalizing two-point correlation functions in the dual matrix theory.

  7. The EGF Receptor Promotes the Malignant Potential of Glioma by Regulating Amino Acid Transport System xc(-).

    Science.gov (United States)

    Tsuchihashi, Kenji; Okazaki, Shogo; Ohmura, Mitsuyo; Ishikawa, Miyuki; Sampetrean, Oltea; Onishi, Nobuyuki; Wakimoto, Hiroaki; Yoshikawa, Momoko; Seishima, Ryo; Iwasaki, Yoshimi; Morikawa, Takayuki; Abe, Shinya; Takao, Ayumi; Shimizu, Misato; Masuko, Takashi; Nagane, Motoo; Furnari, Frank B; Akiyama, Tetsu; Suematsu, Makoto; Baba, Eishi; Akashi, Koichi; Saya, Hideyuki; Nagano, Osamu

    2016-05-15

    Extracellular free amino acids contribute to the interaction between a tumor and its microenvironment through effects on cellular metabolism and malignant behavior. System xc(-) is composed of xCT and CD98hc subunits and functions as a plasma membrane antiporter for the uptake of extracellular cystine in exchange for intracellular glutamate. Here, we show that the EGFR interacts with xCT and thereby promotes its cell surface expression and function in human glioma cells. EGFR-expressing glioma cells manifested both enhanced antioxidant capacity as a result of increased cystine uptake, as well as increased glutamate, which promotes matrix invasion. Imaging mass spectrometry also revealed that brain tumors formed in mice by human glioma cells stably overexpressing EGFR contained higher levels of reduced glutathione compared with those formed by parental cells. Targeted inhibition of xCT suppressed the EGFR-dependent enhancement of antioxidant capacity in glioma cells, as well as tumor growth and invasiveness. Our findings establish a new functional role for EGFR in promoting the malignant potential of glioma cells through interaction with xCT at the cell surface. Cancer Res; 76(10); 2954-63. ©2016 AACR.

  8. A New Multichelating Acid System for High-Temperature Sandstone Reservoirs

    Directory of Open Access Journals (Sweden)

    Nianyin Li

    2015-01-01

    Full Text Available Sandstone reservoir acidizing is a complex and heterogeneous acid-rock reaction process. If improper acid treatment is implemented, further damage can be induced instead of removing the initial plug, particularly in high-temperature sandstone reservoirs. An efficient acid system is the key to successful acid treatment. High-temperature sandstone treatment with conventional mud acid system faces problems including high acid-rock reaction rate, short acid effective distance, susceptibility to secondary damage, and serious corrosion to pipelines. In this paper, a new multichelating acid system has been developed to overcome these shortcomings. The acid system is composed of ternary weak acid, organic phosphonic chelating agent, anionic polycarboxylic acid chelating dispersant, fluoride, and other assisted additives. Hydrogen ion slowly released by multistage ionization in ternary weak acid and organic phosphonic within the system decreases the concentration of HF to achieve retardation. Chelating agent and chelating dispersant within the system inhibited anodic and cathodic reaction, respectively, to protect the metal from corrosion, while chelating dispersant has great chelating ability on iron ions, restricting the depolarization reaction of ferric ion and metal. The synergic effect of chelating agent and chelating dispersant removes sulfate scale precipitation and inhibits or decreases potential precipitation such as CaF2, silica gel, and fluosilicate. Mechanisms of retardation, corrosion-inhibition, and scale-removing features have been discussed and evaluated with laboratory tests. Test results indicate that this novel acid system has good overall performance, addressing the technical problems and improving the acidizing effect as well for high-temperature sandstone.

  9. Optimization of Multiple and Multipurpose Reservoir System Operations by Using Matrix Structure (Case Study: Karun and Dez Reservoir Dams.

    Directory of Open Access Journals (Sweden)

    Mohammad Heydari

    Full Text Available Optimal operation of water resources in multiple and multipurpose reservoirs is very complicated. This is because of the number of dams, each dam's location (Series and parallel, conflict in objectives and the stochastic nature of the inflow of water in the system. In this paper, performance optimization of the system of Karun and Dez reservoir dams have been studied and investigated with the purposes of hydroelectric energy generation and providing water demand in 6 dams. On the Karun River, 5 dams have been built in the series arrangements, and the Dez dam has been built parallel to those 5 dams. One of the main achievements in this research is the implementation of the structure of production of hydroelectric energy as a function of matrix in MATLAB software. The results show that the role of objective function structure for generating hydroelectric energy in weighting method algorithm is more important than water supply. Nonetheless by implementing ε- constraint method algorithm, we can both increase hydroelectric power generation and supply around 85% of agricultural and industrial demands.

  10. Optimization of Multiple and Multipurpose Reservoir System Operations by Using Matrix Structure (Case Study: Karun and Dez Reservoir Dams).

    Science.gov (United States)

    Heydari, Mohammad; Othman, Faridah; Taghieh, Mahmood

    2016-01-01

    Optimal operation of water resources in multiple and multipurpose reservoirs is very complicated. This is because of the number of dams, each dam's location (Series and parallel), conflict in objectives and the stochastic nature of the inflow of water in the system. In this paper, performance optimization of the system of Karun and Dez reservoir dams have been studied and investigated with the purposes of hydroelectric energy generation and providing water demand in 6 dams. On the Karun River, 5 dams have been built in the series arrangements, and the Dez dam has been built parallel to those 5 dams. One of the main achievements in this research is the implementation of the structure of production of hydroelectric energy as a function of matrix in MATLAB software. The results show that the role of objective function structure for generating hydroelectric energy in weighting method algorithm is more important than water supply. Nonetheless by implementing ε- constraint method algorithm, we can both increase hydroelectric power generation and supply around 85% of agricultural and industrial demands. PMID:27248152

  11. Some properties of horn equation model of ultrasonic system vibration and of transfer matrix and equivalent circuit methods of its solution.

    Science.gov (United States)

    Hornišová, K; Billik, P

    2014-01-01

    Traditional technique of horn equation solved by transfer matrices as a model of vibration of ultrasonic systems consisting of sectional transducer, horn and load is discussed. Expression of vibration modes as a ratio of solutions of two Schrödinger equations gives better insight to the structure of a transfer matrix and properties of amplitudes of displacement and strain, and enables more systematic search for analytic solutions. Incorrectness of impedance matrix method and of equivalent circuit method on one hand and correctness and advantages of transfer matrix method in avoiding numerical artifacts and revealing the real features of the model on the other hand are demonstrated on examples. Discontinuous dependence of the nth resonant value on parameters of ultrasonic system, recently described in Sturm-Liouville theory, and consequently, a jump from half-wave to full-wave mode, is observed in a transducer model.

  12. Abscisic Acid: Hidden Architect of Root System Structure

    Directory of Open Access Journals (Sweden)

    Jeanne M. Harris

    2015-08-01

    Full Text Available Plants modulate root growth in response to changes in the local environment, guided by intrinsic developmental genetic programs. The hormone Abscisic Acid (ABA mediates responses to different environmental factors, such as the presence of nitrate in the soil, water stress and salt, shaping the structure of the root system by regulating the production of lateral roots as well as controlling root elongation by modulating cell division and elongation. Curiously, ABA controls different aspects of root architecture in different plant species, perhaps providing some insight into the great diversity of root architecture in different plants, both from different taxa and from different environments. ABA is an ancient signaling pathway, acquired well before the diversification of land plants. Nonetheless, how this ancient signaling module is implemented or interacts within a larger signaling network appears to vary in different species. This review will examine the role of ABA in the control of root architecture, focusing on the regulation of lateral root formation in three plant species, Arabidopsis thaliana, Medicago truncatula and Oryza sativa. We will consider how the implementation of the ABA signaling module might be a target of natural selection, to help contribute to the diversity of root architecture in nature.

  13. A new chemical system solution for acid gas removal

    Energy Technology Data Exchange (ETDEWEB)

    Seiler, M.; Rolker, J.; Witthaut, D.; Schulze, S. [Evonik Industries AG, Hanau (Germany); Buchholz, S. [Evonik Industries AG, Marl (Germany)

    2012-07-01

    An energy-efficient absorbent formulation fors eparating acid gases (e.g. CO{sub 2}, H2S) from gas streams such as natural gas, syngas or flue gas is important for a number of industrial applications. In many cases, a substantial share of their costs is driven by the operational expenditure (OPEX) of the CO{sub 2} separation unit. One possible strategy for reducing OPEX is the improvement of the absorbent performance. Although a number of absorbents for the separation of CO{sub 2} from gas streams exist, there is still a need to develop CO{sub 2} absorbents with an improved absorption performance, less corrosion and foaming, no nitrosamine formation, lower energy requirement and therefore less OPEX. This contribution aims at giving a brief state-of-the-art overview followed by an introduction and performance characterization of a new family of amine-based CO{sub 2} absorbents. High cyclic capacities in the range of 2.9 to 3.2 mol CO{sub 2} kg{sup -1} absorbent and low absorption enthalpies of about -30 kJ mol{sup -1} allow for significant savings in the regeneration energy of the new absorbent system. Calculations with the modified Kremser model indicate a reduction in the specific reboiler heat duty of 45 %. Moreover, the high-performance absorbents developed show much lower corrosion rates than state-of-the-art solutions that are currently employed. (orig.)

  14. Liquid chromatography/electrospray ionization/isotopic dilution mass spectrometry analysis of n-(phosphonomethyl) glycine and mass spectrometry analysis of aminomethyl phosphonic acid in environmental water and vegetation matrixes.

    Science.gov (United States)

    Grey, L; Nguyen, B; Yang, P

    2001-01-01

    A liquid chromatography/electrospray/mass spectrometry (LC/ES/MS) method was developed for the analysis of glyphosate (n-phosphonomethyl glycine) and its metabolite, aminomethyl phosphonic acid (AMPA) using isotope-labelled glyphosate as a method surrogate. Optimized parameters were achieved to derivatize glyphosate and AMPA using 9-fluorenylmethyl chloroformate (FMOC-Cl) in borate buffer prior to a reversed-phase LC analysis. Method spike recovery data obtained using laboratory and real world sample matrixes indicated an excellent correlation between the recovery of the native and isotope-labelled glyphosate. Hence, the first performance-based, isotope dilution MS method with superior precision, accuracy, and data quality was developed for the analysis of glyphosate. There was, however, no observable correlation between the isotope-labelled glyphosate and AMPA. Thus, the use of this procedure for the accurate analysis of AMPA was not supported. Method detection limits established using standard U.S. Environmental Protection Agency protocol were 0.06 and 0.30 microg/L, respectively, for glyphosate and AMPA in water matrixes and 0.11 and 0.53 microg/g, respectively, in vegetation matrixes. Problems, solutions, and the method performance data related to the analysis of chlorine-treated drinking water samples are discussed. Applying this method to other environmental matrixes, e.g., soil, with minimum modifications is possible, assuring accurate, multimedia studies of glyphosate concentration in the environment and the delivery of useful multimedia information for regulatory applications.

  15. Simultaneous integration of mixed quantum-classical systems by density matrix evolution equations using interaction representation and adaptive time step integrator

    NARCIS (Netherlands)

    Lensink, M.F; Mavri, J.; Berendsen, H.J.C.

    1996-01-01

    A density matrix evolution method [H. J. C. Berendsen and J. Mavri, J. Phys. Chem., 97, 13464 (1993)] to simulate the dynamics of quantum systems embedded in a classical environment is applied to study the inelastic collisions of a classical particle with a five-level quantum harmonic oscillator. We

  16. Sequence-specific nucleic acid mobility using a reversible block copolymer gel matrix and DNA amphiphiles (lipid-DNA) in capillary and microfluidic electrophoretic separations.

    Science.gov (United States)

    Wagler, Patrick; Minero, Gabriel Antonio S; Tangen, Uwe; de Vries, Jan Willem; Prusty, Deepak; Kwak, Minseok; Herrmann, Andreas; McCaskill, John S

    2015-10-01

    Reversible noncovalent but sequence-dependent attachment of DNA to gels is shown to allow programmable mobility processing of DNA populations. The covalent attachment of DNA oligomers to polyacrylamide gels using acrydite-modified oligonucleotides has enabled sequence-specific mobility assays for DNA in gel electrophoresis: sequences binding to the immobilized DNA are delayed in their migration. Such a system has been used for example to construct complex DNA filters facilitating DNA computations. However, these gels are formed irreversibly and the choice of immobilized sequences is made once off during fabrication. In this work, we demonstrate the reversible self-assembly of gels combined with amphiphilic DNA molecules, which exhibit hydrophobic hydrocarbon chains attached to the nucleobase. This amphiphilic DNA, which we term lipid-DNA, is synthesized in advance and is blended into a block copolymer gel to induce sequence-dependent DNA retention during electrophoresis. Furthermore, we demonstrate and characterize the programmable mobility shift of matching DNA in such reversible gels both in thin films and microchannels using microelectrode arrays. Such sequence selective separation may be employed to select nucleic acid sequences of similar length from a mixture via local electronics, a basic functionality that can be employed in novel electronic chemical cell designs and other DNA information-processing systems. PMID:26095642

  17. Matrix inequalities

    CERN Document Server

    Zhan, Xingzhi

    2002-01-01

    The main purpose of this monograph is to report on recent developments in the field of matrix inequalities, with emphasis on useful techniques and ingenious ideas. Among other results this book contains the affirmative solutions of eight conjectures. Many theorems unify or sharpen previous inequalities. The author's aim is to streamline the ideas in the literature. The book can be read by research workers, graduate students and advanced undergraduates.

  18. Comparison of cellular effects of starch-coated SPIONs and poly(lactic-co-glycolic acid matrix nanoparticles on human monocytes

    Directory of Open Access Journals (Sweden)

    Gonnissen D

    2016-10-01

    Full Text Available Dominik Gonnissen,1 Ying Qu,1,2 Klaus Langer,3 Cengiz Öztürk,4 Yuliang Zhao,2 Chunying Chen,2 Guiscard Seebohm,5 Martina Düfer,6 Harald Fuchs,1 Hans-Joachim Galla,7 Kristina Riehemann11Center for Nanotechnology, Institute of Physics, University of Münster, Münster, Germany; 2National Center for Nanoscience and Technology, Chinese Academy of Sciences, Beijing, People’s Republic of China; 3Institute of Pharmaceutical Technology and Biopharmacy, University of Münster, Münster, 4chemicell GmbH, Berlin, 5Department of Cardiovascular Medicine, Institute for Genetics of Heart Diseases, University Hospital Münster, 6Department of Pharmacology, Institute of Pharmaceutical and Medicinal Chemistry, 7Department of Cell Biology/Biophysics, Institute of Biochemistry, University of Münster, Münster, GermanyAbstract: Within the last years, progress has been made in the knowledge of the properties of medically used nanoparticles and their toxic effects, but still, little is known about their influence on cellular processes of immune cells. The aim of our comparative study was to present the influence of two different nanoparticle types on subcellular processes of primary monocytes and the leukemic monocyte cell line MM6. We used core-shell starch-coated superparamagnetic iron oxide nanoparticles (SPIONs and matrix poly(lactic-co-glycolic acid (PLGA nanoparticles for our experiments. In addition to typical biocompatibility testing like the detection of necrosis or secretion of interleukins (ILs, we investigated the impact of these nanoparticles on the actin cytoskeleton and the two voltage-gated potassium channels Kv1.3 and Kv7.1. Induction of necrosis was not seen for PLGA nanoparticles and SPIONs in primary monocytes and MM6 cells. Likewise, no alteration in secretion of IL-1β and IL-10 was detected under the same experimental conditions. In contrast, IL-6 secretion was exclusively downregulated in primary monocytes after contact with both

  19. Effects of extracellular matrix proteins on macrophage differentiation, growth, and function: comparison of liquid and agar culture systems

    Science.gov (United States)

    Armstrong, J. W.; Chapes, S. K.; Spooner, B. S. (Principal Investigator)

    1994-01-01

    Both spaceflight and skeletal unloading suppress the haematopoietic differentiation of macrophages (Sonnenfeld et al., Aviat. Space Environ. Med., 61:648-653, 1990; Armstrong et al., J. Appl. Physiol., 75:2734-2739, 1993). The mechanism behind this reduction in haematopoiesis has yet to be elucidated. However, changes in bone marrow extracellular matrix (ECM) may be involved. To further understand the role of ECM products in macrophage differentiation, we have performed experiments evaluating the effects of fibronectin, laminin, collagen type I, and collagen type IV on macrophage development and function. Bone marrow-derived macrophages cultured on four different ECM substrates in liquid culture medium showed less growth than those cultured on plastic. Significant morphological differences were seen on each of the substrates used. Phenotypically and functionally, as measured by class II major histocompatibility molecule (MHCII) expression, MAC-2 expression, and the secretion of interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-alpha), these macrophages were similar. In contrast, bone marrow-derived macrophages cultured in suspension, using agar, showed no difference in growth when exposed to ECM proteins. However, IL-6 and TNF-alpha secretion was affected by fibronectin, laminin, collagen type I, and collagen type IV in a concentration-dependent manner. We conclude that the ECM products fibronectin, laminin, collagen type I, and collagen type IV have profound effects on macrophage development and function. Additionally, we suggest that an ECM-supplemented agar culture system provides an environment more analogous to in vivo bone marrow than does a traditional liquid culture system.

  20. Artificial extracellular matrix proteins containing phenylalanine analogues biosynthesized in bacteria using T7 expression system and the PEGylation.

    Science.gov (United States)

    Takasu, Akinori; Kondo, Shiori; Ito, Akihiro; Furukawa, Yuya; Higuchi, Masahiro; Kinoshita, Takatoshi; Kwon, Inchan

    2011-10-10

    In vivo incorporation of phenylalanine (Phe) analogues into an artificial extracellular matrix protein (aECM-CS5-ELF) was accomplished using a bacterial expression host that harbors the mutant phenylalanyl-tRNA synthetase (PheRS) with an enlarged binding pocket. Although the Ala294Gly/Thr251Gly mutant PheRS (PheRS**) under the control of T5 promoter allows incorporation of some Phe analogues into a protein, the T5 system is not suitable for material science studies because the amount of materials produced is not sufficient due to the moderate strength of the T5 promoter. This limitation can be overcome by using a pair of T7 promoter and T7 RNA polymerase instead. In the T7 expression system, it is difficult, however, to achieve a high incorporation level of Phe analogues, due to competition of Phe analogues for incorporation with the residual Phe that is required for synthesis of active T7 RNA polymerase. In this study, we prepared the PheRS** under T7 promoter and optimized culture condition to improve both the incorporation level of recombinant aECM protein and the incorporation level of Phe analogues. Incorporation and expression levels tend to increase in the case of p-azidophenylalanine, p-iodophenylalanine, and p-acetylphenylalanine. We evaluated the lower critical transition temperature, which is dependent on the incorporation ratio and the turbidity decreased when the incorporation level increased. Circular dichromism measurement indicated that this tendency is based on conformational change from random coil to β-turn structure. We demonstrated that polyethylene glycol (PEG) can be conjugated at reaction site of Phe analogues incorporated. We also demonstrated that the increased hydrophilicity of elastin-like sequences in the aECM-CS5-ELF made by PEG conjugation could suppress nonspecific adhesion of human umbilical vein endothelial cells (HUVEC).