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Sample records for activity electrophoretic mobility

  1. Electrophoretic mobilities of erythrocytes in various buffers

    NASA Technical Reports Server (NTRS)

    Plank, L. D.; Kunze, M. E.; Todd, P. W.

    1985-01-01

    The calibration of space flight equipment depends on a source of standard test particles, this test particle of choice is the fixed erythrocyte. Erythrocytes from different species have different electrophoretic mobilities. Electrophoretic mobility depends upon zeta potential, which, in turn depends upon ionic strength. Zeta potential decreases with increasing ionic strength, so cells have high electrophoretic mobility in space electrophoresis buffers than in typical physiological buffers. The electrophoretic mobilities of fixed human, rat, and rabbit erythrocytes in 0.145 M salt and buffers of varying ionic strength, temperature, and composition, to assess the effects of some of the unique combinations used in space buffers were characterized. Several effects were assessed: glycerol or DMSO (dimethylsulfoxide) were considered for use as cryoprotectants. The effect of these substances on erythrocyte electrophoretic mobility was examined. The choice of buffer depended upon cell mobility. Primary experiments with kidney cells established the choice of buffer and cryoprotectant. A nonstandard temperature of EPM in the suitable buffer was determined. A loss of ionic strength control occurs in the course of preparing columns for flight, the effects of small increases in ionic strength over the expected low values need to be evaluated.

  2. ELECTROPHORETIC MOBILITY OF MYCOBACTERIUM AVIUM COMPLEX ORGANISMS

    EPA Science Inventory

    The electrophoretic mobilities (EPMs) of thirty Mycobacterium avium Complex (MAC) organisms were measured. The EPMs of fifteen clinical isolates ranged from -1.9 to -5.0 µm cm V-1s-1, and the EPMs of fifteen environmental isolates ranged from -1...

  3. ELECTROPHORETIC MOBILITY OF MYCOBACTERIUM AVIUM COMPLEX ORGANISMS

    EPA Science Inventory

    The electrophoretic mobilities (EPMs) of thirty Mycobacterium avium Complex (MAC) organisms isolated from clinical and environmental sources were measured in 9.15 mM KH2PO4 buffered water. The EPMs of fifteen clinical isolates ranged from -1.9 to -5.0 µm cm V-1 ...

  4. Controlled method of reducing electrophoretic mobility of various substances

    NASA Technical Reports Server (NTRS)

    Vanalstine, James M. (Inventor)

    1989-01-01

    A method of reducing electrophoretic mobility of macromolecules, particles, cells, and the like is provided. The method comprises interacting the particles or cells with a polymer-linked affinity compound composed of: a hydrophilic neutral polymer such as polyethylene glycol, and an affinity component consisting of a hydrophobic compound such as a fatty acid ester, an immunocompound such as an antibody or active fragment thereof or simular macromolecule, or other ligands. The reduction of electrophoretic mobility achieved is directly proportional to the concentration of the polymer-linked affinity compound employed, and the mobility reduction obtainable is up to 100 percent for particular particles and cells. The present invention is advantageous in that analytical electrophoretic separation can not be achieved for macromolecules, particles, and cells whose native surface charge structure had prevented them from being separated by normal electrophoretic means. Depending on the affinity component utilized, separation can be achieved on the basis of specific/irreversible, specific/reversible, semi-specific/reversible, relatively nonspecific/reversible, or relatively nonspecific/irreversible ligand-substance interactions. The present method is also advantageous in that it can be used in a variety of standard laboratory electrophoresis equipment.

  5. Electrophoretic mobility of oil droplets in electrolyte and surfactant solutions.

    PubMed

    Wuzhang, Jiachen; Song, Yongxin; Sun, Runzhe; Pan, Xinxiang; Li, Dongqing

    2015-10-01

    Electrophoretic mobility of oil droplets of micron sizes in PBS and ionic surfactant solutions was measured in this paper. The experimental results show that, in addition to the applied electric field, the speed and the direction of electrophoretic motion of oil droplets depend on the surfactant concentration and on if the droplet is in negatively charged SDS solutions or in positively charged hexadecyltrimethylammonium bromide (CTAB) solutions. The absolute value of the electrophoretic mobility increases with increased surfactant concentration before the surfactant concentration reaches to the CMC. It was also found that there are two vortices around the oil droplet under the applied electric field. The size of the vortices changes with the surfactant and with the electric field. The vortices around the droplet directly affect the drag of the flow field to the droplet motion and should be considered in the studies of electrophoretic mobility of oil droplets. The existence of the vortices will also influence the determination and the interpretation of the zeta potential of the oil droplets based on the measured mobility data. PMID:26140616

  6. Alternative to polyacrylamide gels improves the electrophoretic mobility shift assay.

    PubMed

    Vanek, P G; Fabian, S J; Fisher, C L; Chirikjian, J G; Collier, G B

    1995-04-01

    In this paper we outline a simplified protocol for the electrophoretic mobility shift assay utilizing TreviGel 500, a nontoxic alternative to polyacrylamide. The TreviGel 500 matrix combines the strength and resolution of polyacrylamide with the simplicity and flexibility of agarose in the casting of gels. Therefore, this method provides a simple, rapid and nontoxic alternative to current protocols for the investigation of protein: DNA interactions.

  7. The Electrophoretic Mobility of Proteins near Surfaces

    NASA Astrophysics Data System (ADS)

    Ramasamy, Perumal; Singh, Avtar; Rafailovich, Miriam; Sokolov, Jonathan

    2004-03-01

    We have attempted to apply the methods developed for surface DNA electrophoresis (1) for proteomics. Droplets of FITC stained Abumin, Poly- L-Lysine, or Casein purchased from Sigma were deposited on glass cover slips. The droplets were then place in contact with a TBE buffer solution contained in a cell molded from PDMS. Pt electrodes were inserted into the cell and a voltage was a applied. The motion of the protein was then imaged with a Leica Confocal microscope as a function of buffer concentration, distance from the surface, and applied voltage. The mobilities were then compared with those of uncharged one micron florescent Polystyrene beads. References: 1)Henzel WJ, Watanabe C, Stults JT., !0 Protein Identification: The Origins of Peptide Mass Fingerprinting. !1 J. American Society for Mass Spectrometry. 14 (September 2003): 931-942 2)Mathesius U, Imin N, Natera SH, Rolfe BG., !0 Proteomics as a functional genomics tool. !1 Methods of Molecular Biology 236: 395-414. *Work supported in part by the NSF-MRSEC program

  8. Controlled method of reducing electrophoretic mobility of macromolecules, particles, or cells

    NASA Technical Reports Server (NTRS)

    Vanalstine, James M. (Inventor)

    1992-01-01

    A method of reducing electrophoretic mobility of macromolecules, particles, cells, and other substances is provided which comprises interacting in a conventional electrophoretic separating procedure, the substances with a polymer-linked affinity compound comprised of a hydrophilic neutral polymer such as polyethylene glycol bound to a second component such as a hydrophobic compound, an immunocompound such as an antibody or antibody active fragment, or a ligand such as a hormone, drug, antigen, or a hapten. The reduction of electrophoretic mobility achieved is directly proportional to the concentration of the polymer-linked affinity compound employed, and such reduction can comprise up to 100 percent for particular particles and cells. The present invention is advantageous in that electrophoretic separation can now be achieved for substances whose native surface charge structure had prevented them from being separated by normal electrophoretic means. Depending on the affinity component utilized, separation can be achieved on the basis of the specific/irreversible, specific/reversible, semi-specific/reversible, relatively nonspecific/reversible, or relatively nonspecific/irreversible ligand-substance interactions.

  9. Electrophoretic mobilities of counterions and a polymer in cylindrical pores

    PubMed Central

    Singh, Sunil P.; Muthukumar, M.

    2014-01-01

    We have simulated the transport properties of a uniformly charged flexible polymer chain and its counterions confined inside cylindrical nanopores under an external electric field. The hydrodynamic interaction is treated by describing the solvent molecules explicitly with the multiparticle collision dynamics method. The chain consisting of charged monomers and the counterions interact electrostatically with themselves and with the external electric field. We find rich behavior of the counterions around the polymer under confinement in the presence of the external electric field. The mobility of the counterions is heterogeneous depending on their location relative to the polymer. The adsorption isotherm of the counterions on the polymer depends nonlinearly on the electric field. As a result, the effective charge of the polymer exhibits a sigmoidal dependence on the electric field. This in turn leads to a nascent nonlinearity in the chain stretching and electrophoretic mobility of the polymer in terms of their dependence on the electric field. The product of the electric field and the effective polymer charge is found to be the key variable to unify our simulation data for various polymer lengths. Chain extension and the electrophoretic mobility show sigmoidal dependence on the electric field, with crossovers from the linear response regime to the nonlinear regime and then to the saturation regime. The mobility of adsorbed counterions is nonmonotonic with the electric field. For weaker and moderate fields, the adsorbed counterions move with the polymer and at higher fields they move opposite to the polymer's direction. We find that the effective charge and the mobility of the polymer decrease with a decrease in the pore radius. PMID:25240366

  10. Electrophoretic mobility of cells in a vertical Ficoll gradiant

    NASA Technical Reports Server (NTRS)

    Plank, L. D.; Todd, P. W.; Kunze, M. E.; Gaines, R. A.

    1985-01-01

    The upward migration of living cells and test particles under the influence of a constant electric field in a low conductivity Ficoll gradient occurs at nearly constant velocity. Viscosity and neutral polymer concentration affect migration rate. Decreasing viscosity speeds up the particle migration, decreasing neutral polymer (Ficoll) concentration, slows particle migration, since electrophoretic mobility increases approximately linearly with neutral polymer concentration. Neutral polymers interact with the cell surface to effectively raise its zeta potential. An analytic function was developed from the known dependence of these physical variables on migration distance; the analysis expresses migration velocity as an explicit function of position in the density gradient. It predicts an almost linear increase in velocity of about 12 to 16% over the working region of the gradient. It was numerically integrated and correctly predicts cell migration distance vs time curves without the use of any fitted parameters. The resulting migration curves follow the expected slowly varying exponential form that closely resembles a straight line. The ability to determine standard electrophoretic mobilities from such curves depends on knowledge of the effect of Ficoll on the zeta potential of the cell type that is separated.

  11. Electrophoretic mobilities of cultured human embryonic kidney cells in various buffers

    NASA Technical Reports Server (NTRS)

    1985-01-01

    Data on the electrophoretic mobility distributions of cells in the new D-1 buffer and the interlaboratory standardization of urokinase assay methods are presented. A table of cell strains and recent data on cell dispersal methods are also included. It was decided that glycerol in A-1 electrophoretic mobility data on cultured human embryonic kidney cells subjected to electrophoresis in this buffer. The buffer composition is presented.

  12. Effect of passage number on electrophoretic mobility distributions of cultured human embryonic kidney cells

    NASA Technical Reports Server (NTRS)

    Kunze, M. E.

    1985-01-01

    A systematic investigation was undertaken to characterize population shifts that occur in cultured human embryonic kidney cells as a function of passage number in vitro after original explantation. This approach to cell population shift analysis follows the suggestion of Mehreshi, Klein and Revesz that perturbed cell populations can be characterized by electrophoretic mobility distributions if they contain subpopulations with different electrophoretic mobilities. It was shown that this is the case with early passage cultured human embryo cells.

  13. Relating chromatographic retention and electrophoretic mobility to the ion distribution within electrosprayed droplets.

    PubMed

    Bökman, C Fredrik; Bylund, Dan; Markides, Karin E; Sjöberg, Per J R

    2006-03-01

    Ions that are observed in a mass spectrum obtained with electrospray mass spectrometry can be assumed to originate preferentially from ions that have a high distribution to the surface of the charged droplets. In this study, a relation between chromatographic retention and electrophoretic mobility to the ion distribution (derived from measured signal intensities in mass spectra and electrospray current) within electrosprayed droplets for a series of tetraalkylammonium ions, ranging from tetramethyl to tetrapentyl, is presented. Chromatographic retention in a reversed-phase system was taken as a measure of the analyte's surface activity, which was found to have a large influence on the ion distribution within electrosprayed droplets. In addition, different transport mechanisms such as electrophoretic migration and diffusion can influence the surface partitioning coefficient. The viscosity of the solvent system is affected by the methanol content and will influence both diffusion and ion mobility. However, as diffusion and ion mobility are proportional to each other, we have, in this study, chosen to focus on the ion mobility parameter. It was found that the influence of ion mobility relative to surface activity on the droplet surface partitioning of analyte ions decreases with increasing methanol content. This effect is most probably coupled to the decrease in droplet size caused by the decreased surface tension at increasing methanol content. The same observation was made upon increasing the ionic strength of the solvent system, which is also known to give rise to a decreased initial droplet size. The observed effect of ionic strength on the droplet surface partitioning of analyte ions could also be explained by the fact that at higher ionic strength, a larger number of ions are initially closer to the droplet surface and, thus, the contribution of ionic transport from the bulk liquid to the liquid/air surface interface (jet and droplet surface), attributable to

  14. Electrophoretic mobilities of neutral analytes and electroosmotic flow markers in aqueous solutions of Hofmeister salts.

    PubMed

    Křížek, Tomáš; Kubíčková, Anna; Hladílková, Jana; Coufal, Pavel; Heyda, Jan; Jungwirth, Pavel

    2014-03-01

    Small neutral organic compounds have traditionally the role of EOF markers in electrophoresis, as they are expected to have zero electrophoretic mobility in external electric fields. The BGE contains, however, ions that have unequal affinities to the neutral molecules, which in turn results in their mobilization. In this study we focused on two EOF markers-thiourea and DMSO, as well as on N-methyl acetamide (NMA) as a model of the peptide bond. By means of CE and all atom molecular dynamics simulations we explored mobilization of these neutral compounds in large set of Hofmeister salts. Employing a statistical mechanics approach, we were able to reproduce by simulations the experimental electrophoretic mobility coefficients. We also established the role of the chemical composition of marker and the BGE on the measured electrophoretic mobility coefficient. For NMA, we interpreted the results in terms of the relative affinities of cations versus anions to the peptide bond.

  15. Electrophoretic mobility as a tool to separate immune adjuvant saponins from Quillaja saponaria Molina.

    PubMed

    Gilabert-Oriol, Roger; Weng, Alexander; von Mallinckrodt, Benedicta; Stöshel, Anja; Nissi, Linda; Melzig, Matthias F; Fuchs, Hendrik; Thakur, Mayank

    2015-06-20

    Quillaja saponins are used as adjuvants in animal vaccines but their application in human vaccination is still under investigation. Isolation and characterization of adjuvant saponins is very tedious. Furthermore, standardization of Quillaja saponins is critical pertaining to its application in humans. In this study, a convenient method based on agarose gel electrophoresis was developed for the separation of Quillaja saponins. Six different commercial Quillaja saponins were segregated by size/charge into numerous fractions. Each of the fractions was characterized by ESI-TOF-MS spectroscopy and thin layer chromatography. Real-time impedance-based monitoring and red blood cell lysis assay were used to evaluate cytotoxicity and hemolytic activities respectively. Two specific regions in the agarose gel (delimited by specific relative electrophoretic mobility values) were identified and characterized by exclusive migration of acylated saponins known to possess immune adjuvant properties (0.18-0.58), and cytotoxic and hemolytic saponins (0.18-0.94). In vivo experiments in mice with the isolated fractions for evaluation of adjuvant activity also correlated with the relative electrophoretic mobility. In addition to the separation of specific Quillaja saponins with adjuvant effects as a pre-purification step to HPLC, agarose gel electrophoresis stands out as a new method for rapid screening, separation and quality control of saponins. PMID:25839418

  16. The electrophoretic mobility of montmorillonite. Zeta potential and surface conductivity effects.

    PubMed

    Leroy, Philippe; Tournassat, Christophe; Bernard, Olivier; Devau, Nicolas; Azaroual, Mohamed

    2015-08-01

    Clay minerals have remarkable adsorption properties because of their high specific surface area and surface charge density, which give rise to high electrochemical properties. These electrochemical properties cannot be directly measured, and models must be developed to estimate the electrostatic potential at the vicinity of clay mineral surfaces. In this context, an important model prediction is the zeta potential, which is thought to be representative of the electrostatic potential at the plane of shear. The zeta potential is usually deduced from electrophoretic measurements but for clay minerals, high surface conductivity decreases their mobility, thereby impeding straightforward interpretation of these measurements. By combining a surface complexation, conductivity and electrophoretic mobility model, we were able to reconcile zeta potential predictions with electrophoretic measurements on montmorillonite immersed in NaCl aqueous solutions. The electrochemical properties of the Stern and diffuse layers of the basal surfaces were computed by a triple-layer model. Computed zeta potentials have considerably higher amplitudes than measured zeta potentials calculated with the Smoluchowski equation. Our model successfully reproduced measured electrophoretic mobilities. This confirmed our assumptions that surface conductivity may be responsible for montmorillonite's low electrophoretic mobility and that the zeta potential may be located at the beginning of the diffuse layer.

  17. Alteration of the electrophoretic mobility of human peripheral blood mononuclear cells following treatment with dimethyl sulfoxide

    SciTech Connect

    Skrabut, E.M.; Catsimpoolas, N.; Kurtz, S.R.; Griffith, A.L.; Valeri, C.R.

    1983-12-01

    Studies have been conducted to determine the effects of DMSO and freezing on the electrophoretic distribution of peripheral blood mononuclear cells. Sodium (/sup 51/Cr)chromate was used to label the cells, and the distributions of cell number and cell-associated radioactivity were determined. Cells treated with DMSO had a narrower distribution of electrophoretic mobilities when compared with those not treated. DMSO-treated cells also demonstrated a more homogeneous distribution of radioactivity relative to the cell distribution than did the nontreated cells. The freezing of DMSO-treated cells did not result in any additional alteration of electrophoretic pattern compared to DMSO treatment alone. Analysis by linear categorization techniques indicated that the DMSO-treated and nontreated cells were completely distinguished by their electrophoretic behavior.

  18. Characterization of the Cell Surface Properties of Drinking Water Pathogens by Microbial Adhesion to Hydrocarbon and Electrophoretic Mobility Measurements

    EPA Science Inventory

    The surface characteristics of microbial cells directly influence their mobility and behavior within aqueous environments. The cell surface hydrophobicity (CSH) and electrophoretic mobility (EPM) of microbial cells impact a number of interactions and processes including aggregati...

  19. ELECTROPHORETIC MOBILITIES OF ESCHERICHIA COLI 0157:H7 AND WILD-TYPE ESCHERICHIA COLI STRAINS

    EPA Science Inventory

    The electrophoretic mobility (EPM) of a number of human-virulent and "wild-type" Escherichia coli strains in phosphate buffered water was measured. The impact of pH, ionic strength, cation type (valence) and concentration, and bacterial strain on the EPM was investigated. Resul...

  20. Electrophoretic mobility of supercoiled, catenated and knotted DNA molecules

    PubMed Central

    Cebrián, Jorge; Kadomatsu-Hermosa, Maridian J.; Castán, Alicia; Martínez, Víctor; Parra, Cristina; Fernández-Nestosa, María José; Schaerer, Christian; Martínez-Robles, María-Luisa; Hernández, Pablo; Krimer, Dora B.; Stasiak, Andrzej; Schvartzman, Jorge B.

    2015-01-01

    We systematically varied conditions of two-dimensional (2D) agarose gel electrophoresis to optimize separation of DNA topoisomers that differ either by the extent of knotting, the extent of catenation or the extent of supercoiling. To this aim we compared electrophoretic behavior of three different families of DNA topoisomers: (i) supercoiled DNA molecules, where supercoiling covered the range extending from covalently closed relaxed up to naturally supercoiled DNA molecules; (ii) postreplicative catenanes with catenation number increasing from 1 to ∼15, where both catenated rings were nicked; (iii) knotted but nicked DNA molecules with a naturally arising spectrum of knots. For better comparison, we studied topoisomer families where each member had the same total molecular mass. For knotted and supercoiled molecules, we analyzed dimeric plasmids whereas catenanes were composed of monomeric forms of the same plasmid. We observed that catenated, knotted and supercoiled families of topoisomers showed different reactions to changes of agarose concentration and voltage during electrophoresis. These differences permitted us to optimize conditions for their separation and shed light on physical characteristics of these different types of DNA topoisomers during electrophoresis. PMID:25414338

  1. Simultaneous sizing and electrophoretic mobility measurement of sub-micron particles using Brownian motion.

    PubMed

    Palanisami, Akilan; Miller, John H

    2010-10-01

    The size and surface chemistry of micron scale particles are of fundamental importance in studies of biology and air particulate pollution. However, typical electrophoretic measurements of these and other sub-micron scale particles (300 nm-1 μm) cannot resolve size information within heterogeneous mixtures unambiguously. Using optical microscopy, we monitor electrophoretic motion together with the Brownian velocity fluctuations - using the latter to measure size by either the Green-Kubo relation or by calibration from known size standards. Particle diameters are resolved to ±12% with 95% confidence. Strikingly, the size resolution improves as the particle size decreases due to the increased Brownian motion. The sizing ability of the Brownian assessed electrophoresis method described here complements the electrophoretic mobility resolution of the traditional CE. PMID:20882556

  2. Cobalt ferrite nanoparticles with improved aqueous colloidal stability and electrophoretic mobility

    NASA Astrophysics Data System (ADS)

    Munjal, Sandeep; Khare, Neeraj

    2016-04-01

    We have synthesized CoFe2O4 (CFO) nanoparticles of size ˜ 12.2 nm by hydrothermal synthesis method. To control the size of these CFO nanoparticles, oleic acid was used as a surfactant. The inverse spinel phase of the synthesized nanoparticles was confirmed by X-ray diffraction method. As synthesized oleic acid coated CFO (OA@CFO) nanoparticles has very less electrophoretic mobility in the water and are not water dispersible. These OA@CFO nanoparticles were successfully turned into water soluble phase with a better colloidal aqueous stability, through a chemical treatment using citric acid. The modified citric acid coated CFO (CA@CFO) nanoparticles were dispersible in water and form a stable aqueous solution with high electrophoretic mobility.

  3. Electrophoretic Mobility of Poly(acrylic acid)-Coated Alumina Particles

    SciTech Connect

    Bhosale, Prasad S.; Chun, Jaehun; Berg, John C.

    2011-06-01

    The effect of poly (acrylic acid) (PAA) adsorption on the electrokinetic behavior of alumina dispersions under high pH conditions was investigated as a function of polymer concentration and molecular weight as well as the presence, concentration and ion type of background electrolyte. Systems of this type are relevant to nuclear waste treatment, in which PAA is known to be an effective rheology modifier. The presence of all but the lowest molecular weight PAA studied (1800) led to decreases in dynamic electrophoretic mobility at low polymer concentrations, attributable to bridging flocculation, as verified by measurements of particle size distribution. Bridging effects increased with polymer molecular weight, and decreased with polymer concentration. Increases in background electrolyte concentration enhanced dynamic electrophoretic mobility as the polymer layers were compressed and bridging was reduced. Such enhancements were reduced as the cation was changed from Na+ to K+ to Cs+.

  4. Electrophoretic mobility of silica particles in a mixture of toluene and ethanol at different particle concentrations.

    PubMed

    Medrano, M; Pérez, A T; Lobry, L; Peters, F

    2009-10-20

    In this paper we present measurements of the electrophoretic mobility of colloidal particles by using heterodyne detection of light scattering. The measurements have been made up to concentrations of 5.4% silica nanoparticles, with a diameter on the order of 80 nm, in a mixture of 70% toluene and 30% ethanol. To make possible the measurements at these concentrations, the liquid mixture is chosen so as to match the index of refraction of the particles, thus resulting in a transparent suspension.

  5. Sequence dependent electrophoretic mobilities and melting temperatures for A-T containing oligodeoxyribonucleotides.

    PubMed Central

    Wilson, W D; Zuo, E T; Jones, R L; Zon, G L; Baumstark, B R

    1987-01-01

    The electrophoretic mobilities and thermal melting properties of self complementary A-T containing dodecamer oligodeoxyribonucleotides have been investigated as a function of solution conditions. The oligomers contained tracts of nonalternating A-T base pairs of 2 (d(A2T2)3), 3 (d(A3T3)2), and 6 (d(A6T6] as well as the fully alternating (d(A-T)6) sequence. The melting temperature increased with the length of the nonalternating sequence and was approximately 12 degrees C higher in the d(A6T6) sequence than in the alternating oligomer. Under denaturing conditions all oligomers had the same electrophoretic mobility on acrylamide gels. Under conditions which favor duplex formation, the oligomers exhibited significant sequence dependent mobility differences. The mobilities of two oligomers, d(A-T)6 and d(A6-T6), were approximately equal and were less than those of the other oligonucleotides. The greatest mobility was observed for d(A2T2)3. These results are best explained by a model which requires bending at a junction of two or more continuous A or T bases with another sequence. Images PMID:3822802

  6. High-Throughput Electrophoretic Mobility Shift Assays for Quantitative Analysis of Molecular Binding Reactions

    PubMed Central

    2015-01-01

    We describe a platform for high-throughput electrophoretic mobility shift assays (EMSAs) for identification and characterization of molecular binding reactions. A photopatterned free-standing polyacrylamide gel array comprised of 8 mm-scale polyacrylamide gel strips acts as a chassis for 96 concurrent EMSAs. The high-throughput EMSAs was employed to assess binding of the Vc2 cyclic-di-GMP riboswitch to its ligand. In optimizing the riboswitch EMSAs on the free-standing polyacrylamide gel array, three design considerations were made: minimizing sample injection dispersion, mitigating evaporation from the open free-standing polyacrylamide gel structures during electrophoresis, and controlling unit-to-unit variation across the large-format free-standing polyacrylamide gel array. Optimized electrophoretic mobility shift conditions allowed for 10% difference in mobility shift baseline resolution within 3 min. The powerful 96-plex EMSAs increased the throughput to ∼10 data/min, notably more efficient than either conventional slab EMSAs (∼0.01 data/min) or even microchannel based microfluidic EMSAs (∼0.3 data/min). The free-standing polyacrylamide gel EMSAs yielded reliable quantification of molecular binding and associated mobility shifts for a riboswitch–ligand interaction, thus demonstrating a screening assay platform suitable for riboswitches and potentially a wide range of RNA and other macromolecular targets. PMID:25233437

  7. The rate with which spontaneous mutation alters the electrophoretic mobility of polypeptides.

    PubMed Central

    Neel, J V; Satoh, C; Goriki, K; Fujita, M; Takahashi, N; Asakawa, J; Hazama, R

    1986-01-01

    Studies of a Japanese population, involving a total of 539,170 locus tests distributed over 36 polypeptides, yielded three presumptive spontaneous mutations altering the electrophoretic mobility of the polypeptide. This corresponds to a mutation rate of 0.6 X 10(-5) per locus per generation. The a priori probability that undetected discrepancies between legal and biological parentage might in our test system result in an apparent electrophoretic mutation in this population is calculated to be only 0.3 X 10(-7) per locus per generation. Since electrophoresis only detects about half of the amino acid substitutions due to mutations of nucleotides, the corrected rate for mutations causing amino acid substitutions in polypeptides is 1.2 X 10(-5) per locus per generation. With allowance for synonymous mutations and those resulting in stop codons, the total mutation rate for nucleotide changes in the exons encoding a polypeptide becomes approximately equal to 1.8 X 10(-5) per locus per generation. When the present observations are combined with all of the other available data concerning mutation resulting in electrophoretic variants, the electrophoretic rate drops to 0.3 X 10(-5) per locus per generation, the total locus rate drops to roughly 1.0 X 10(-5), and the nucleotide rate drops to 1 X 10(-8). Even with this lower estimate, given approximately equal to 2 X 10(9) nucleotides in the haploid genome and an average of 10(3) exon nucleotides per polypeptide encoded, the implication, if these exon rates can be generalized, is of approximately equal to 20 nucleotide mutations per gamete per generation. This estimate of the frequency of "point" mutations does not include small duplications, rearrangements, or deletions resulting from unequal crossing-over, transcription errors, etc. PMID:3455776

  8. The influence of hydrodynamic slip on the electrophoretic mobility of a spherical colloidal particle

    NASA Astrophysics Data System (ADS)

    Khair, Aditya S.; Squires, Todd M.

    2009-04-01

    Recent theoretical studies have suggested a significant enhancement in electro-osmotic flows over hydrodynamically slipping surfaces, and experiments have indeed measured O(1) enhancements. In this paper, we investigate whether an equivalent effect occurs in the electrophoretic motion of a colloidal particle whose surface exhibits hydrodynamic slip. To this end, we compute the electrophoretic mobility of a uniformly charged spherical particle with slip length λ as a function of the zeta (or surface) potential of the particle ζ and diffuse-layer thickness κ-1. In the case of a thick diffuse layer, κa ≪1 (where a is the particle size), simple arguments show that slip does lead to an O(1) enhancement in the mobility, owing to the reduced viscous drag on the particle. On the other hand, for a thin-diffuse layer κa ≫1, the situation is more complicated. A detailed asymptotic analysis, following the method of O'Brien [J. Colloid Interface Sci. 92, 204 (1983)], reveals that an O(κλ) increase in the mobility occurs at low-to-moderate zeta potentials (with ζ measured on the scale of thermal voltage kBT /e≈25 mV). However, as ζ is further increased, the mobility decreases and ultimately becomes independent of the slip length—the enhancement is lost—which is due to the importance of nonuniform surface conduction within the thin-diffuse layer, at large ζ and large, but finite, κa. Our asymptotic calculations for thick and thin-diffuse layers are corroborated and bridged by computation of the mobility from the numerical solution of the full electrokinetic equations (using the method of O'Brien and White [J. Chem. Soc., Faraday Trans. 2 74, 1607 (1978)]). In summary, then, we demonstrate that hydrodynamic slip can indeed produce an enhancement in the electrophoretic mobility; however, such enhancements will not be as dramatic as the previously studied κa →∞ limit would suggest. Importantly, this conclusion applies not only to electrophoresis but also to

  9. An electrophoretic mobility shift assay identifies a mechanistically unique inhibitor of protein sumoylation.

    PubMed

    Kim, Yeong Sang; Nagy, Katelyn; Keyser, Samantha; Schneekloth, John S

    2013-04-18

    The dynamic, posttranslational modification of proteins with a small ubiquitin-like modifier (SUMO) tag has been recognized as an important cellular regulatory mechanism relevant to a number of cancers as well as normal embryonic development. As part of a program aimed toward the identification of inhibitors of SUMO-conjugating enzymes, we developed a microfluidic electrophoretic mobility shift assay to monitor sumoylation events in real time. We disclose herein the use of this assay to identify a cell-permeable compound capable of blocking the transfer of SUMO-1 from the E2 enzyme Ubc9 to the substrate. We screened a small collection of compounds and identified an oxygenated flavonoid derivative that inhibits sumoylation in vitro. Next, we carried out an in-depth mechanistic analysis that ruled out many common false-positive mechanisms such as aggregation or alkylation. Furthermore, we report that this flavonoid inhibits a single step in the sumoylation cascade: the transfer of SUMO from the E2 enzyme (Ubc9) thioester conjugate to the substrate. In addition to having a unique mechanism of action, this inhibitor has a discrete structure-activity relationship uncharacteristic of a promiscuous inhibitor. Cell-based studies showed that the flavonoid inhibits the sumoylation of topoisomerase-I in response to camptothecin treatment in two different breast cancer cell lines, while isomeric analogs are inactive. Importantly, this compound blocks sumoylation while not affecting ubiquitylation in cells. This work identifies a point of entry for pharmacologic inhibition of the sumoylation cascade and may serve as the basis for continued study of additional pharmacophores that modulate SUMO-conjugating enzymes such as Ubc9. PMID:23601649

  10. Electrophoretic Mobility Shift Assays for Protein–DNA Complexes Involved in DNA Repair*

    PubMed Central

    Tsai, Chun; Smider, Vaughn; Hwang, Byung Joon; Chu, Gilbert

    2014-01-01

    The electrophoretic mobility shift assay (EMSA) can be used to study proteins that bind to DNA structures created by DNA-damaging agents. UV-damaged DNA-binding protein (UV-DDB), which is involved in nucleotide excision repair, binds to DNA damaged by ultraviolet radiation or the anticancer drug cisplatin. Ku, XRCC4/Ligase IV, and DNA–PKcs, which are involved in the repair of DNA double-strand breaks by nonhomologous end joining, assemble in complexes at DNA ends. This chapter will describe several EMSA protocols for detecting different DNA repair protein–DNA complexes. To obtain additional information, one can apply variations of the EMSA, which include the reverse EMSA to detect binding of 35S-labeled protein to damaged DNA, and the antibody supershift assay to detect the presence of a specific protein in the protein–DNA complex. PMID:22941596

  11. Effect of pH on the Electrophoretic Mobility of Spores of Bacillus anthracis and Its Surrogates in Aqueous Solutions

    EPA Science Inventory

    Electrophoretic mobility (EPM) of endospores of Bacillus anthracis and surrogates were measured in aqueous solution across a broad pH range and several ionic strengths. EPM values trended around phylogenetic clustering based on the 16S rRNA gene. Measurements reported here prov...

  12. Using Electrophoretic Mobility Shift Assays to Measure Equilibrium Dissociation Constants: GAL4-p53 Binding DNA as a Model System

    ERIC Educational Resources Information Center

    Heffler, Michael A.; Walters, Ryan D.; Kugel, Jennifer F.

    2012-01-01

    An undergraduate biochemistry laboratory experiment is described that will teach students the practical and theoretical considerations for measuring the equilibrium dissociation constant (K[subscript D]) for a protein/DNA interaction using electrophoretic mobility shift assays (EMSAs). An EMSA monitors the migration of DNA through a native gel;…

  13. Effect of pH on the Electrophoretic Mobility of Spores of Bacillus anthracis and Its Surrogates in Aqueous Solutions

    PubMed Central

    Popovici, Jonathan; Lytle, Darren A.; Adcock, Noreen J.; Rice, Eugene W.

    2012-01-01

    The electrophoretic mobility (EPM) of endospores of Bacillus anthracis and surrogates was measured in aqueous solution across a broad pH range and several ionic strengths. EPM values trended around phylogenetic clustering based on the 16S rRNA gene. Measurements reported here provide new insight for Bacillus anthracis surrogate selection and for attachment/detachment and transport studies. PMID:23001659

  14. Electrophoretic mobilities of the complexes between sodium dodecyl sulfate and various peptides or proteins determined by free solution electrophoresis using coated capillaries.

    PubMed

    Karim, M R; Shinagawa, S; Takagi, T

    1994-01-01

    Electrophoretic mobilities of various proteins or peptides complexed with sodium dodecyl sulfate (SDS) were determined by free solution capillary electrophoresis. The complexes formed between SDS and protein polypeptide showed electrophoretic mobilities virtually insensitive to the protein molecular weight. On the other hand, scattered and larger negative electrophoretic mobilities were observed for peptides of molecular weights less than 10000. Mobility differences as small as 0.3-3% among the three differently modified derivatives of bovine serum albumin could also be successfully determined due to the high resolving power of capillary electrophoresis.

  15. Mapping DNA quantity into electrophoretic mobility through quantum dot nanotethers for high-resolution genetic and epigenetic analysis.

    PubMed

    Zhang, Yi; Liu, Kelvin J; Wang, Tian-Li; Shih, Ie-Ming; Wang, Tza-Huei

    2012-01-24

    Newly discovered nanoparticle properties have driven the development of novel applications and uses. We report a new observation where the electrophoretic mobility of a quantum dot/DNA nanoassembly can be precisely modulated by the degree of surface DNA conjugation. By using streptavidin-coated quantum dots (QDs) as nanotethers to gather biotin-labeled DNA into electrophoretic nanoassemblies, the QD surface charge is modulated and transformed into electrophoretic mobility shifts using standard agarose gel electrophoresis. Typical fluorescent assays quantify based on relative intensity. However, this phenomenon uses a novel approach that accurately maps DNA quantity into shifts in relative band position. This property was applied in a QD-enabled nanoassay called quantum dot electrophoretic mobility shift assay (QEMSA) that enables accurate quantification of DNA targets down to 1.1-fold (9%) changes in quantity, beyond what is achievable in qPCR. In addition to these experimental findings, an analytical model is presented to explain this behavior. Finally, QEMSA was applied to both genetic and epigenetic analysis of cancer. First, it was used to analyze copy number variation (CNV) of the RSF1/HBXAP gene, where conventional approaches for CNV analysis based on comparative genomic hybridization (CGH), microarrays, and qPCR are unable to reliably differentiate less than 2-fold changes in copy number. Then, QEMSA was used for DNA methylation analysis of the p16/CDK2A tumor suppressor gene, where its ability to detect subtle changes in methylation was shown to be superior to that of qPCR.

  16. Rapid agarose gel electrophoretic mobility shift assay for quantitating protein: RNA interactions.

    PubMed

    Ream, Jennifer A; Lewis, L Kevin; Lewis, Karen A

    2016-10-15

    Interactions between proteins and nucleic acids are frequently analyzed using electrophoretic mobility shift assays (EMSAs). This technique separates bound protein:nucleic acid complexes from free nucleic acids by electrophoresis, most commonly using polyacrylamide gels. The current study utilizes recent advances in agarose gel electrophoresis technology to develop a new EMSA protocol that is simpler and faster than traditional polyacrylamide methods. Agarose gels are normally run at low voltages (∼10 V/cm) to minimize heating and gel artifacts. In this study we demonstrate that EMSAs performed using agarose gels can be run at high voltages (≥20 V/cm) with 0.5 × TB (Tris-borate) buffer, allowing for short run times while simultaneously yielding high band resolution. Several parameters affecting band and image quality were optimized for the procedure, including gel thickness, agarose percentage, and applied voltage. Association of the siRNA-binding protein p19 with its target RNA was investigated using the new system. The agarose gel and conventional polyacrylamide gel methods generated similar apparent binding constants in side-by-side experiments. A particular advantage of the new approach described here is that the short run times (5-10 min) reduce opportunities for dissociation of bound complexes, an important concern in non-equilibrium nucleic acid binding experiments. PMID:27495142

  17. Polar Residues in Transmembrane Helices can Decrease Electrophoretic Mobility in Polyacrylamide Gels Without Causing Helix Dimerization

    PubMed Central

    Walkenhorst, William F.; Merzlyakov, Mikhail; Hristova, Kalina; Wimley, William C.

    2010-01-01

    There are only a few available methods to study lateral interactions and self assembly of transmembrane helices. One of the most frequently used methods is sodium dodecylsulfate polyacrylamide gel electrophoresis (SDS-PAGE) which can report on strong interactions between peptides in SDS solution. Here we offer a cautionary tale about studying the folding and assembly of membrane proteins using peptides and SDS-PAGE experiments as membrane mimetic systems. At least for the specific peptide and detergent systems studied here, we show that a polar asparagine residue in the 12th position of an otherwise hydrophobic helical segment of 20 amino acids causes a peptide to migrate on SDS-PAGE gels with an apparent molecular weight that is twice its true molecular weight, suggesting dimerization. However when examined carefully in SDS solutions and in situ in the polyacrylamide gel itself using Forster resonance energy transfer no interaction can be detected. Instead we show evidence suggesting that differential interactions between peptide and detergent drive the differences in electrophoretic mobility without any interaction between peptides. These results emphasize the need to apply multiple independent techniques to the study of membrane protein folding, and they highlight the usefulness of studying folding and structure of membrane proteins in lipid membranes rather than in detergents. PMID:19265670

  18. Determination of electrokinetic and hydrodynamic parameters of proteins by modeling their electrophoretic mobilities through the electrically charged spherical porous particle.

    PubMed

    Deiber, Julio A; Piaggio, Maria V; Peirotti, Marta B

    2013-03-01

    This work explores the possibility of using the electrically charged "spherical porous particle" (SPP) to model the electrophoretic mobility of proteins in the low charge regime. In this regard, the electrophoretic mobility expression of the charged SPP (Hermans-Fujita model) is used and applied here to BSA and staphylococcal nuclease for different protocol pH values. The SPP is presented within the general framework of the "spherical soft particle" as described in the literature. The physicochemical conditions required to model proteins as SPP from their experimentally determined electrophoretic mobilities are established. It is shown that particle permeability and porosity and chain packing and friction fractal dimensions are relevant structural properties of proteins when hydrodynamic interaction between amino acid residues is present. The charge regulation phenomenon of BSA and staphylococcal nuclease with pIs ≈ 5.71 and 9.63, respectively, is described through the SPP within a wide range of bulk pH values. These case studies illustrate when the average regulating {pH} of the protein domain is lower and higher than the protocol pH. Further research for using the general spherical soft particle is also proposed on the basis of results and main conclusions.

  19. Determination of electrokinetic and hydrodynamic parameters of proteins by modeling their electrophoretic mobilities through the electrically charged spherical soft particle.

    PubMed

    Deiber, Julio A; Piaggio, María V; Peirotti, Marta B

    2013-03-01

    This work explores the possibility of using the electrically charged "spherical soft particle" (SSP) to model the electrophoretic mobility of proteins in the low charge regime. The general framework concerning the electrophoretic mobility of the SSP already presented in the literature is analyzed and discussed here in particular for polyampholyte-polypeptide chains. In this regard, this theory is applied to BSA for different protocol pH values. The physicochemical conditions required to model proteins as SSP from their experimentally determined electrophoretic mobilities are established. In particular, the protein charge regulation phenomenon and the SSP particle core are included to study BSA having isoelectric point pI ≈ 5.71, within a wide range of bulk pH values. The results of this case study are compared with previous ones concerning the spherical porous particle and the spherical hard particle with occluded water. A discussion of chain conformations in the SSP polyampholyte layer is presented through estimations of the packing and friction fractal dimensions.

  20. Easy measurement and analysis method of zeta potential and electrophoretic mobility of water-dispersed colloidal particles by using a self-mixing solid-state laser

    NASA Astrophysics Data System (ADS)

    Sudo, S.; Ohtomo, T.; Otsuka, K.

    2013-08-01

    We describe a highly sensitive method of measuring electrophoretic mobility and zeta potential of water-dispersed colloidal particles by using a self-mixing laser Doppler velocimeter with a laser-diode-pumped, thin-slice solid-state laser with extremely high optical sensitivity. The power spectra of laser output modulated by reinjected laser light scattered by the electrophoretic particles were observed. The power spectrum cannot be described by the well-known formula for translational motion or flowing Brownian motion, i.e., a combination of Doppler shift, diffusion, and translation. The power spectra shape is found to reflect the velocity distribution of electrophoretic particles in a capillary tube due to the electro-osmotic flow contribution. Not only evaluation of the electrophoretic mobility and zeta potential but also the particle diameter undergoing electrophoretic motion can be performed from the shape of the power spectrum.

  1. Some anomalous effects of sodium ions on the electrophoretic mobility and heteroaggregation of microgel particles.

    PubMed

    Routh, Alexander F; Vincent, Brian

    2004-05-15

    Experiments on the kinetics of heteroaggregation between oppositely charged particles, using both dynamic light scattering and turbidity methods, are reported. The negatively charged particles were cross-linked poly( [Formula: see text] -isopropylacrylamide) [PNIPAM] microgel particles, prepared using a carboxylic-acid-based initiator; these particles are swollen at room temperature. The positive particles were poly(4-vinylpyridine) [P4VP] particles, prepared using an amidinium-based initiator; such particles do not respond to temperature changes but do swell below pH approximately 4, where the pyridine moieties become protonated. As expected, the rate of heteroaggregation was shown to be largely independent of added salt concentration (up to approximately 20 mM), for a variety of alkali metal chlorides (MCl, where M = Li, Na, K, or Rb). However, an unexpected, significant decrease in the aggregation rate was observed at certain specific sodium chloride concentrations (typically at approximately 1 and also approximately 4 mM). Similar effects were not seen with the other alkali metal chloride salts. This strange effect was eventually attributed to the fact that the net charge on the positively charged P4VP particles had been reduced by the adsorption of (anionic) silicate species leached from the glassware container. Sodium silicates are known to be significantly more soluble than those of the other alkali metal ions, particularly at high pH. Moreover, P4VP particles dispersed in water, ostensibly at neutral pH, do buffer the aqueous medium to pH values around 9 or higher. This mechanism was confirmed by determining the electrophoretic mobility of the P4VP particles as a function of pH in the presence of the various alkali metal chloride salts. The mobility remained positive in 1 mM salt solutions over the pH range 3 to 11 for all the salts, except for sodium chloride; in that case the mobility reversed sign at alkaline pH values. A similar effect was observed for

  2. Understanding the poor iontophoretic transport of lysozyme across the skin: when high charge and high electrophoretic mobility are not enough.

    PubMed

    Dubey, S; Kalia, Y N

    2014-06-10

    The original aim of the study was to investigate the transdermal iontophoretic delivery of lysozyme and to gain further insight into the factors controlling protein electrotransport. Initial experiments were done using porcine skin. Lysozyme transport was quantified by using an activity assay based on the lysis of Micrococcus lysodeikticus and was corrected for the release of endogenous enzyme from the skin during current application. Cumulative iontophoretic permeation of lysozyme during 8h at 0.5mA/cm(2) (0.7mM; pH6) was surprisingly low (5.37±3.46μg/cm(2) in 8h) as compared to electrotransport of cytochrome c (Cyt c) and ribonuclease A (RNase A) under similar conditions (923.0±496.1 and 170.71±92.13μg/cm(2), respectively) - despite its having a higher electrophoretic mobility. The focus of the study then became to understand and explain the causes of its poor iontophoretic transport. Lowering formulation pH to 5 increased histidine protonation in the protein and decreased the ionisation of fixed negative charges in the skin (pI ~4.5) and resulted in a small but statistically significant increase in permeation. Co-iontophoresis of acetaminophen revealed a significant inhibition of electroosmosis; inhibition factors of 12-16 were indicative of strong lysozyme binding to skin. Intriguingly, lidocaine electrotransport, which is due almost exclusively to electromigration, was also decreased (approximately 2.7-fold) following skin pre-treatment by lysozyme iontophoresis (cf. iontophoresis of buffer solution) - suggesting that lysozyme was also able to influence subsequent cation electromigration. In order to elucidate the site of skin binding, different porcine skin models were tested (dermatomed skin with thicknesses of 250 and 750μm, tape-stripped skin and heat-separated dermis). Although no difference was seen between permeation across 250 and 750μm dermatomed skin (13.57±12.20 and 5.37±3.46μg/cm(2), respectively), there was a statistically significant

  3. Liquid phase separation of proteins based on electrophoretic effects in an electrospray setup during sample introduction into a gas-phase electrophoretic mobility molecular analyzer (CE–GEMMA/CE–ES–DMA)

    PubMed Central

    Weiss, Victor U.; Kerul, Lukas; Kallinger, Peter; Szymanski, Wladyslaw W.; Marchetti-Deschmann, Martina; Allmaier, Günter

    2014-01-01

    Nanoparticle characterization is gaining importance in food technology, biotechnology, medicine, and pharmaceutical industry. An instrument to determine particle electrophoretic mobility (EM) diameters in the single-digit to double-digit nanometer range receiving increased attention is the gas-phase electrophoretic mobility molecular analyzer (GEMMA) separating electrophoretically single charged analytes in the gas-phase at ambient pressure. A fused-silica capillary is used for analyte transfer to the gas-phase by means of a nano electrospray (ES) unit. The potential of this capillary to separate analytes electrophoretically in the liquid phase due to different mobilities is, at measurement conditions recommended by the manufacturer, eliminated due to elevated pressure applied for sample introduction. Measurements are carried out upon constant feeding of analytes to the system. Under these conditions, aggregate formation is observed for samples including high amounts of non-volatile components or complex samples. This makes the EM determination of individual species sometimes difficult, if not impossible. With the current study we demonstrate that liquid phase electrophoretic separation of proteins (as exemplary analytes) occurs in the capillary (capillary zone electrophoresis, CE) of the nano ES unit of the GEMMA. This finding was consecutively applied for on-line desalting allowing EM diameter determination of analytes despite a high salt concentration within samples. The present study is to our knowledge the first report on the use of the GEMMA to determine EM diameters of analytes solubilized in the ES incompatible electrolyte solutions by the intended use of electrophoresis (in the liquid phase) during sample delivery. Results demonstrate the proof of concept of such an approach and additionally illustrate the high potential of a future on-line coupling of a capillary electrophoresis to a GEMMA instrument. PMID:25109866

  4. The 'Densitometric Image Analysis Software' and its application to determine stepwise equilibrium constants from electrophoretic mobility shift assays.

    PubMed

    van Oeffelen, Liesbeth; Peeters, Eveline; Nguyen Le Minh, Phu; Charlier, Daniël

    2014-01-01

    Current software applications for densitometric analysis, such as ImageJ, QuantityOne (BioRad) and the Intelligent or Advanced Quantifier (Bio Image) do not allow to take the non-linearity of autoradiographic films into account during calibration. As a consequence, quantification of autoradiographs is often regarded as problematic, and phosphorimaging is the preferred alternative. However, the non-linear behaviour of autoradiographs can be described mathematically, so it can be accounted for. Therefore, the 'Densitometric Image Analysis Software' has been developed, which allows to quantify electrophoretic bands in autoradiographs, as well as in gels and phosphorimages, while providing optimized band selection support to the user. Moreover, the program can determine protein-DNA binding constants from Electrophoretic Mobility Shift Assays (EMSAs). For this purpose, the software calculates a chosen stepwise equilibrium constant for each migration lane within the EMSA, and estimates the errors due to non-uniformity of the background noise, smear caused by complex dissociation or denaturation of double-stranded DNA, and technical errors such as pipetting inaccuracies. Thereby, the program helps the user to optimize experimental parameters and to choose the best lanes for estimating an average equilibrium constant. This process can reduce the inaccuracy of equilibrium constants from the usual factor of 2 to about 20%, which is particularly useful when determining position weight matrices and cooperative binding constants to predict genomic binding sites. The MATLAB source code, platform-dependent software and installation instructions are available via the website http://micr.vub.ac.be.

  5. Electrophoretic mobility shift in native gels indicates calcium-dependent structural changes of neuronal calcium sensor proteins.

    PubMed

    Viviano, Jeffrey; Krishnan, Anuradha; Wu, Hao; Venkataraman, Venkat

    2016-02-01

    In proteins of the neuronal calcium sensor (NCS) family, changes in structure as well as function are brought about by the binding of calcium. In this article, we demonstrate that these structural changes, solely due to calcium binding, can be assessed through electrophoresis in native gels. The results demonstrate that the NCS proteins undergo ligand-dependent conformational changes that are detectable in native gels as a gradual decrease in mobility with increasing calcium but not other tested divalent cations such as magnesium, strontium, and barium. Surprisingly, such a gradual change over the entire tested range is exhibited only by the NCS proteins but not by other tested calcium-binding proteins such as calmodulin and S100B, indicating that the change in mobility may be linked to a unique NCS family feature--the calcium-myristoyl switch. Even within the NCS family, the changes in mobility are characteristic of the protein, indicating that the technique is sensitive to the individual features of the protein. Thus, electrophoretic mobility on native gels provides a simple and elegant method to investigate calcium (small ligand)-induced structural changes at least in the superfamily of NCS proteins.

  6. Comprehensive Size-Determination of Whole Virus Vaccine Particles Using Gas-Phase Electrophoretic Mobility Macromolecular Analyzer, Atomic Force Microscopy, and Transmission Electron Microscopy

    PubMed Central

    Havlik, Marlene; Marchetti-Deschmann, Martina; Friedbacher, Gernot; Winkler, Wolfgang; Messner, Paul; Perez-Burgos, Laura; Tauer, Christa; Allmaier, Günter

    2015-01-01

    Biophysical properties including particle size distribution, integrity, and shape of whole virus vaccine particles at different stages in tick-borne encephalitis (TBE) vaccines formulation were analyzed by a new set of methods. Size-exclusion chromatography (SEC) was used as a conservative sample preparation for vaccine particle fractionation and gas-phase electrophoretic mobility macromolecular analyzer (GEMMA) for analyzing electrophoretic mobility diameters of isolated TBE virions. The derived particle diameter was then correlated with molecular weight. The diameter of the TBE virions determined after SEC by GEMMA instrumentation was 46.8 ± 1.1 nm. Atomic force microscopy (AFM) and transmission electron microscopy (TEM) were implemented for comparison purposes and to gain morphological information on the virion particle. Western blotting (Dot Blot) as an immunological method confirmed biological activity of the particles at various stages of the developed analytical strategy. AFM and TEM measurements revealed higher diameters with much higher SD for a limited number of virions, 60.4 ± 8.5 and 53.5 ± 5.3 nm, respectively. GEMMA instrumentation was also used for fractionation of virions with specifically selected diameters in the gas-phase, which were finally collected by means of an electrostatic sampler. At that point (i.e., after particle collection), AFM and TEM showed that the sampled virions were still intact, exhibiting a narrow size distribution (i.e., 59.8 ± 7.8 nm for AFM and 47.5 ± 5.2 nm for TEM images), and most importantly, dot blotting confirmed immunological activity of the collected samples. Furthermore dimers and virion artifacts were detected, too. PMID:26266988

  7. The 'Densitometric Image Analysis Software' and its application to determine stepwise equilibrium constants from electrophoretic mobility shift assays.

    PubMed

    van Oeffelen, Liesbeth; Peeters, Eveline; Nguyen Le Minh, Phu; Charlier, Daniël

    2014-01-01

    Current software applications for densitometric analysis, such as ImageJ, QuantityOne (BioRad) and the Intelligent or Advanced Quantifier (Bio Image) do not allow to take the non-linearity of autoradiographic films into account during calibration. As a consequence, quantification of autoradiographs is often regarded as problematic, and phosphorimaging is the preferred alternative. However, the non-linear behaviour of autoradiographs can be described mathematically, so it can be accounted for. Therefore, the 'Densitometric Image Analysis Software' has been developed, which allows to quantify electrophoretic bands in autoradiographs, as well as in gels and phosphorimages, while providing optimized band selection support to the user. Moreover, the program can determine protein-DNA binding constants from Electrophoretic Mobility Shift Assays (EMSAs). For this purpose, the software calculates a chosen stepwise equilibrium constant for each migration lane within the EMSA, and estimates the errors due to non-uniformity of the background noise, smear caused by complex dissociation or denaturation of double-stranded DNA, and technical errors such as pipetting inaccuracies. Thereby, the program helps the user to optimize experimental parameters and to choose the best lanes for estimating an average equilibrium constant. This process can reduce the inaccuracy of equilibrium constants from the usual factor of 2 to about 20%, which is particularly useful when determining position weight matrices and cooperative binding constants to predict genomic binding sites. The MATLAB source code, platform-dependent software and installation instructions are available via the website http://micr.vub.ac.be. PMID:24465496

  8. Determining the electrophoretic mobility and translational diffusion coefficients of DNA molecules in free solution.

    PubMed

    Stellwagen, Earle; Stellwagen, Nancy C

    2002-08-01

    The free solution mobility of DNA molecules of different molecular weights, the sequence dependence of the mobility, and the diffusion coefficients of small single- and double-stranded DNA (ss- and dsDNA) molecules can be measured accurately by capillary zone electrophoresis, using coated capillaries to minimize the electroosmotic flow (EOF) of the solvent. Very small differences in mobility between various analytes can be quantified if a mobility marker is used to correct for small differences in EOF between successive experiments. Using mobility markers, the molecular weight at which the free solution mobility of dsDNA becomes independent of molecular weight is found to be approximately 170 bp in 40 mM Tris-acetate-EDTA buffer. A DNA fragment containing 170 bp has a contour length of approximately 58 nm, close to the persistence length of DNA under these buffer conditions. Hence, the approach of the free solution mobility of DNA to a plateau value may be associated with the transition from a rod-like to a coil-like conformation in solution. Markers have also been used to determine that the free solution mobilities of ss- and dsDNA oligomers are sequence-dependent. Double-stranded 20-bp oligomers containing runs of three or more adenine residues in a row (A-tracts) migrate somewhat more slowly than 20-mers without A-tracts, suggesting that somewhat larger numbers of counterions are condensed in the ion atmospheres of A-tract DNAs, decreasing their net effective charge. Single-stranded 20-mers with symmetric sequences migrate approximately 1% faster than their double-stranded counterparts, and faster than single-stranded 20-mers containing A(5)- or T(5)-tracts. Interestingly, the average mobility of two complementary single-stranded 20-mers is equal to the mobility of the double-stranded oligomer formed upon annealing. Finally, the stopped migration method has been used to measure the diffusion coefficients of single- and double-stranded oligomers. The diffusion

  9. Cationic surfactant adsorption states determined by the dependence of the electrophoretic mobility on dilution

    SciTech Connect

    Chang, C.H.

    1987-01-01

    A dilution method was devised in order to examine the dependence of the mobility of dilute aqueous coal dispersions on concentration. Mobility trends observed on dilution with water and the parent surfactant solution were interpreted in terms of desorption and adsorption of surfactant on coal. The dispersions were also studied by comparing the surface tension of surfactant solutions with the filtrates from a range of coal dispersions. The surfactants used were DTAB (Dodecyltrimethylammonium Bromide), CTAB (Cetyltrimethylammonium Bromide), ATLAS G-271 (N-Soya-N-ethyl morpholinium ethosulfate) and MERPOL-SE, (CH/sub 3/-(CH/sub 2/)/sub 24/-(OCH/sub 2/CH/sub 2/)/sub 8/-OH). The mobility of coal in the presence of cationic surfactant decreased as the dilution ratio increased and reach a constant value. It was also shown that the mobility remained near zero and constant if a non-ionic surfactant was used. On dilution with cationic surfactant solution, the mobility rose to a constant value at high dilution which was more than twice the aqueous asymptote suggesting the separate contribution of reversibility adsorbed surfactant. The structure of surfactant was another effect which controlled the adsorption mechanism. The two major properties of surfactant structure were the hydrophobicity and steric hindrance. The results also implied that hydrophobic tail-adsorbed was the dominant mechanism in contrast to the model which was proposed in earlier studies. Comparison of surface tension between pure surfactant solution and the filtrate from coal/surfactant solution indicated that the surfactants did not all act alike in some cases. Natural surfactant had been desorbed or eluted and in some cases surfactant had been adsorbed.

  10. Using electrophoretic mobility shift assays to measure equilibrium dissociation constants: GAL4-p53 binding DNA as a model system.

    PubMed

    Heffler, Michael A; Walters, Ryan D; Kugel, Jennifer F

    2012-01-01

    An undergraduate biochemistry laboratory experiment is described that will teach students the practical and theoretical considerations for measuring the equilibrium dissociation constant (K(D) ) for a protein/DNA interaction using electrophoretic mobility shift assays (EMSAs). An EMSA monitors the migration of DNA through a native gel; the DNA migrates more slowly when bound to a protein. To determine a K(D) the amount of unbound and protein-bound DNA in the gel is measured as the protein concentration increases. By performing this experiment, students will be introduced to making affinity measurements and gain experience in performing quantitative EMSAs. The experiment describes measuring the K(D) for the interaction between the chimeric protein GAL4-p53 and its DNA recognition site; however, the techniques are adaptable to other DNA binding proteins. In addition, the basic experiment described can be easily expanded to include additional inquiry-driven experimentation. © 2012 by The International Union of Biochemistry and Molecular Biology.

  11. Candies to Dye for: Cooperative, Open-Ended Student Activities to Promote Understanding of Electrophoretic Fractionation

    NASA Astrophysics Data System (ADS)

    Emry, Randall; Curtright, Robert D.; Wright, Jonathan; Markwell, John

    2000-10-01

    A three-part series of laboratory activities is presented that allows students to learn why electrophoretic separations work and to manipulate the factors that influence the separation process. In the first two exercises, students perform cooperative separations of FD&C dyes from candies utilizing electrophoresis in two buffers of different pH. Students must use package information from one brand of candy and critical thinking to determine the identities of these dyes. Using structural formulas for the dyes the students draw conclusions regarding the effect of charge and molecular mass on separation. The final activity is an open-ended investigation into a student-formulated question. These activities integrate topics in biology and chemistry into activities that interest students and foster a real understanding of the tool of electrophoresis.

  12. Electrophoretic mobility of linear and star-branched DNA in semidilute polymer solutions.

    PubMed

    Saha, Sourav; Heuer, Daniel M; Archer, Lynden A

    2006-08-01

    Electrophoresis of large linear T2 (162 kbp) and 3-arm star-branched (N(Arm) = 48.5 kbp) DNA in linear polyacrylamide (LPA) solutions above the overlap concentration c* has been investigated using a fluorescence visualization technique that allows both the conformation and mobility mu of the DNA to be determined. LPA solutions of moderate polydispersity index (PI approximately 1.7-2.1) and variable polymer molecular weight Mw (0.59-2.05 MDa) are used as the sieving media. In unentangled semidilute solutions (c* < c < c(e)), we find that the conformational dynamics of linear and star-branched DNA in electric fields are strikingly different; the former migrating in predominantly U- or I-shaped conformations, depending on electric field strength E, and the latter migrating in a squid-like profile with the star-arms outstretched in the direction opposite to E and dragging the branch point through the sieving medium. Despite these visual differences, mu for linear and star-branched DNA of comparable size are found to be nearly identical in semidilute, unentangled LPA solutions. For LPA concentrations above the entanglement threshold (c > c(e)), the conformation of migrating linear and star-shaped DNA manifest only subtle changes from their unentangled solution features, but mu for the stars decreases strongly with increasing LPA concentration and molecular weight, while mu for linear DNA becomes nearly independent of c and Mw. These findings are discussed in the context of current theories for electrophoresis of large polyelectrolytes. PMID:16850503

  13. Electrophoretic mobility of linear and star-branched DNA in semidilute polymer solutions.

    PubMed

    Saha, Sourav; Heuer, Daniel M; Archer, Lynden A

    2006-08-01

    Electrophoresis of large linear T2 (162 kbp) and 3-arm star-branched (N(Arm) = 48.5 kbp) DNA in linear polyacrylamide (LPA) solutions above the overlap concentration c* has been investigated using a fluorescence visualization technique that allows both the conformation and mobility mu of the DNA to be determined. LPA solutions of moderate polydispersity index (PI approximately 1.7-2.1) and variable polymer molecular weight Mw (0.59-2.05 MDa) are used as the sieving media. In unentangled semidilute solutions (c* < c < c(e)), we find that the conformational dynamics of linear and star-branched DNA in electric fields are strikingly different; the former migrating in predominantly U- or I-shaped conformations, depending on electric field strength E, and the latter migrating in a squid-like profile with the star-arms outstretched in the direction opposite to E and dragging the branch point through the sieving medium. Despite these visual differences, mu for linear and star-branched DNA of comparable size are found to be nearly identical in semidilute, unentangled LPA solutions. For LPA concentrations above the entanglement threshold (c > c(e)), the conformation of migrating linear and star-shaped DNA manifest only subtle changes from their unentangled solution features, but mu for the stars decreases strongly with increasing LPA concentration and molecular weight, while mu for linear DNA becomes nearly independent of c and Mw. These findings are discussed in the context of current theories for electrophoresis of large polyelectrolytes.

  14. [Study of the Sporothrix schenkii (yeast forms) extract. Electrophoretic and immunoelectrophoretic analyses: characterization of enzymatic activities].

    PubMed

    Walbaum, S; Duriez, T; Dujardin, L; Biguet, J

    1978-07-28

    An extract from living yeast forms of S. schenckii was prepared. The yeasts originated from a shake culture in B.H.I. broth (Difco) incubated for 3 days at 35 degrees C in darkness; they were harvested, washed and disrupted with glass beads in a model MSK Braun mechanical cell homogenizer; a freezing-thawing was added to improve the extract. After electrophoretic separation in agarose gel, the extract's components were characterized by their enzymic activity; with this technique, 30 bands were revealed. These enzymic activities were also investigated on the antigenic fractions of the extract revealed by a rabbit hyperimmunserum: 16 among 22 immunoprecipitates are identified by their catalytic properties. Study of the earliest precipitating antibodies (appearing-order and enzymic caracterization) in rabbits just immunized completes this work. How to ameliorate the quality of the extract by culture and extraction conditions is also specified. PMID:692628

  15. Effects of method of detachment on electrophoretic mobility of mammalian cells grown in monolayer culture

    NASA Technical Reports Server (NTRS)

    Plank, L. D.; Kunze, M. E.; Todd, P. W.

    1985-01-01

    A variety of proteolytic and micolytic enzumes, mechanical procedures, and changes in the ionic environment, especially Ca chelation, are used for dispersal of monolayer grown cells. If either chelating agents or mechanical dispersion are used alone, the cell yield is often low and suspensions of single cells are difficult to obtain. Confluent monolayers treated with EDTA tend to be released from their surfaces in sheets, and clumps of cells remain even after further incubation in EDTA. Crude trypsin is the most popular dispersal agent and is known to contain a variety of contaminating enzymes which contribute to the dispersal of cells. A variety of cell injuries resulting from the activity of proteolytic enzymes are reported. It is shown that crystalline trypsin is least harmful to cell integrity as judged by trypan blue uptake.

  16. Electrophoretic and densitometric analysis of esterase activity as an indicator of mercury toxicity

    SciTech Connect

    Benton, M.J.; Guttman, S.I.

    1995-12-31

    In an earlier experiment, esterase activity as determined by starch gel electrophoresis was absent in larval caddisflies (Nectopsyche albida) that succumbed to mercury exposure, but was present in control larvae. To test the effects of mercury exposure duration on esterase activity, additional larval N. albida were exposed under conditions identical to those in the earlier experiment, and esterase activity was determined by electrophoresis of several live individuals every 12 hours. To test the effects of mercury concentration on esterase activity, homogenates of unexposed N. albida were electrophoresed, and esterase activity was determined using esterase-specific stains spiked with various concentrations of mercury. Following both experiments, esterase activity was quantified by laser densitometry of stained electrophoresis gels, Results indicate that: (1) inorganic mercury inhibited esterase activity, (2) inhibition increased with exposure time, and (3) inhibition increased with mercury concentration. Esterase inhibition may be a causal factor in mortality related to mercury exposure. Quantification of esterase activity by densitometry of electrophoretic gels may be an alternative method of rapid toxicity assessment.

  17. Identification of tissue-specific DNA-protein binding sites by means of two-dimensional electrophoretic mobility shift assay display.

    PubMed

    Chernov, Igor P; Timchenko, Kira A; Akopov, Sergey B; Nikolaev, Lev G; Sverdlov, Eugene D

    2007-05-01

    We developed a technique of differential electrophoretic mobility shift assay (EMSA) display allowing identification of tissue-specific protein-binding sites within long genomic sequences. Using this approach, we identified 10 cell type-specific protein-binding sites (protein target sites [PTSs]) within a 137-kb human chromosome 19 region. In general, tissue-specific binding of proteins from different nuclear extracts by individual PTSs did not follow the all-or-nothing principle. Most often, PTS-protein complexes were formed in all cases, but they were different for different nuclear extracts used. PMID:17359930

  18. On the electrophoretic mobility of succinoglycan modelled as a spherical polyelectrolyte: From Hermans-Fujita theory to charge regulation in multi-component electrolytes.

    PubMed

    Hill, Reghan J

    2016-11-15

    Literature interpretations of the electrophoretic mobility of spherical polyelectrolytes are revisited using the capillary-electrophoresis data of Duval et al. (2006) for the extracellular polysaccharide succinoglycan as an example. Subtle changes in the polyelectrolyte mobility have recently been attributed to new electrokinetic theories that feature multi-component electrolytes, charge regulation, and the so-called polarization and relaxation phenomena. However, these calculations exhibit several unusual trends that have yet to be explained, and so the conclusions drawn from them are controversial. Here, independent computations strengthen conclusions drawn from the original model of Duval et al., i.e., the discrepancies between experiments and all the presently available electrokinetic theories reflect changes in the conformation of succinoglycan arising from changes in the electrolyte pH and ionic strength. PMID:27498018

  19. Anti-epileptic drugs and bone loss: Phenytoin reduces pro-collagen I and alters the electrophoretic mobility of osteonectin in cultured bone cells.

    PubMed

    Wilson, Emma L; Garton, Mark; Fuller, Heidi R

    2016-05-01

    Phenytoin is an antiepileptic drug used in the management of partial and tonic-clonic seizures. In previous studies we have shown that valproate, another antiepileptic drug, reduced the amount of two key bone proteins, pro-collagen I and osteonectin (SPARC, BM-40), in both skin fibroblasts and cultured osteoblast-like cells. Here we show that phenytoin also reduces pro-collagen I production in osteoblast-like cells, but does not appear to cause a decrease in osteonectin message or protein production. Instead, a 24h exposure to a clinically relevant concentration of phenytoin resulted in a dose-dependent change in electrophoretic mobility of osteonectin, which was suggestive of a change in post-translational modification status. The perturbation of these important bone proteins could be one of the mechanisms to explain the bone loss that has been reported following long-term treatment with phenytoin.

  20. A simple method for assessment and minimization of errors in determination of electrophoretic or electroosmotic mobilities and velocities associated with the axial electric field distortion.

    PubMed

    Nowak, Paweł Mateusz; Woźniakiewicz, Michał; Kościelniak, Paweł

    2015-12-01

    It is commonly accepted that the modern CE instruments equipped with efficient cooling system enable accurate determination of electrophoretic or electroosmotic mobilities. It is also often assumed that velocity of migration in a given buffer is constant throughout the capillary length. It is simultaneously neglected that the noncooled parts of capillary produce extensive Joule heating leading to an axial electric field distortion, which contributes to a difference between the effective and nominal electric field potentials and between velocities in the cooled and noncooled parts of capillary. This simplification introduces systematic errors, which so far were however not investigated experimentally. There was also no method proposed for their elimination. We show a simple and fast method allowing for estimation and elimination of these errors that is based on combination of a long-end and short-end injections. We use it to study the effects caused by variation of temperature, electric field, capillary length, and pH.

  1. Analysis of a common cold virus and its subviral particles by gas-phase electrophoretic mobility molecular analysis and native mass spectrometry.

    PubMed

    Weiss, Victor U; Bereszcazk, Jessica Z; Havlik, Marlene; Kallinger, Peter; Gösler, Irene; Kumar, Mohit; Blaas, Dieter; Marchetti-Deschmann, Martina; Heck, Albert J R; Szymanski, Wladyslaw W; Allmaier, Günter

    2015-09-01

    Gas-phase electrophoretic mobility molecular analysis (GEMMA) separates nanometer-sized, single-charged particles according to their electrophoretic mobility (EM) diameter after transition to the gas-phase via a nano electrospray process. Electrospraying as a soft desorption/ionization technique preserves noncovalent biospecific interactions. GEMMA is therefore well suited for the analysis of intact viruses and subviral particles targeting questions related to particle size, bioaffinity, and purity of preparations. By correlating the EM diameter to the molecular mass (Mr) of standards, the Mr of analytes can be determined. Here, we demonstrate (i) the use of GEMMA in purity assessment of a preparation of a common cold virus (human rhinovirus serotype 2, HRV-A2) and (ii) the analysis of subviral HRV-A2 particles derived from such a preparation. (iii) Likewise, native mass spectrometry was employed to obtain spectra of intact HRV-A2 virions and empty viral capsids (B-particles). Charge state resolution for the latter allowed its Mr determination. (iv) Cumulatively, the data measured and published earlier were used to establish a correlation between the Mr and EM diameter for a range of globular proteins and the intact virions. Although a good correlation resulted from this analysis, we noticed a discrepancy especially for the empty and subviral particles. This demonstrates the influence of genome encapsulation (preventing analytes from shrinking upon transition into the gas-phase) on the measured analyte EM diameter. To conclude, GEMMA is useful for the determination of the Mr of intact viruses but needs to be employed with caution when subviral particles or even empty viral capsids are targeted. The latter could be analyzed by native MS.

  2. Electrophoretic mobility of the capsid protein of the Plum pox virus strain PPV-Rec indicates its partial phosphorylation.

    PubMed

    Subr, Z; Ryslava, H; Kollerova, E

    2007-01-01

    A double-band SDS-PAGE profile was found reproducible for capsid protein (CP) of Plum pox virus (PPV) isolates belonging to the strain PPV-Rec. The double-band was also present in the virus population multiplied in various plants. A single-lesion passage in a hypersensitive host Chenopodium foetidum showed that its presence was not a result of a mixed infection. We found that the two electrophoretic forms of CP shared identical N-terminus. Therefore, they did not originate from an alternative proteolytic processing, but were different in their posttranslational modification. The slower band of CP could be converted to the faster one by the phosphatase treatment. We assumed that CP protein was present in both phosphorylated and dephosphorylated forms in the infected plants.

  3. Electrophoretic cell separation by means of immunomicrospheres

    NASA Technical Reports Server (NTRS)

    Rembaum, A.; Smolka, A. J. K.

    1980-01-01

    The electrophoretic mobility of fixed human red blood cells immunologically labeled with polymeric (4-vinyl)pyridine or polyglutaraldehyde microspheres was altered to a considerable extent. This observation was utilized in the preparative scale electrophoretic separation of human and turkey fixed red blood cells, whose mobilities under normal physiological conditions do not differ sufficiently to allow their separation by continuous flow electrophoresis. It is suggested that resolution in the electrophoretic separation of cell subpopulations, currently limited by finite and often overlapping mobility distributions, may be significantly enhanced by immuno-specific labeling of target populations using microspheres.

  4. Electrophoretic separation of kidney and pituitary cells on STS-8

    NASA Astrophysics Data System (ADS)

    Morrison, D. R.; Nachtwey, D. S.; Barlow, G. H.; Cleveland, C.; Lanham, J. W.; Farrington, M. A.; Hatfield, J. M.; Hymer, W. C.; Todd, P.; Wilfinger, W.; Grindeland, R.; Lewis, M. L.

    A Continuous Flow Electrophoresis System (CFES) was used on Space Shuttle flight STS-8 to separate specific secretory cells from suspensions of cultured primary human embryonic kidney cells and rat pituitary cells. The objectives were to isolate the subfractions of kidney cells that produce the largest amounts of urokinase (plasminogen activator), and to isolate the subfractions of rat pituitary cells that secrete growth hormone, prolactin, and other hormones. Kidney cells were separated into more than 32 fractions in each of two electrophoretic runs. Electrophoretic mobility distributions in flight experiments were spread more than the ground controls. Multiple assay methods confirmed that all cultured kidney cell fractions produced some urokinase, and five to six fractions produced significantly more urokinase than the other fractions. Several fractions also produced tissue plasminogen activator. The pituitary cells were separated into 48 fractions in each of the two electrophoretic runs, and the amounts of growth hormone (GH) and prolactin (PRL) released into the medium for each cell fraction were determined. Cell fractions were grouped into eight mobility classes and immunocytochemically assayed for the presence of GH, PRL, ACTH, LH, TSH, and FSH. The patterns of hormone distribution indicate that the specialized cells producing GH and PRL are isolatable due to the differences in electrophoretic mobilities.

  5. An integrated electrophoretic mobility control device with split design for signal improvement in liquid chromatography-electrospray ionization mass spectrometry analysis of aminoglycosides using a heptafluorobutyric acid containing mobile phase.

    PubMed

    Hung, Sih-Hua; Yu, Meng-Ju; Wang, Nan-Hsuan; Hsu, Ren-Yu; Wei, Guor-Jien; Her, Guor-Rong

    2016-08-24

    Electrophoretic mobility control (EMC) was used to alleviate the adverse effect of the ion-pairing agent heptafluorobutyric acid (HFBA) in the liquid chromatography-electrospray ionization mass spectrometry (LC-ESI-MS) analysis of aminoglycosides. Aminoglycosides separated by LC were directed to a connecting column before their detection via ESI. Applying an electric field across the connecting column caused the positively charged aminoglycosides to migrate toward the mass spectrometer whereas the HFBA anions remained in the junction reservoir, thus alleviating the ion suppression caused by HFBA. To accommodate the flow rate of a narrow-bore column, minimize the effect of electrophoretic mobility on separation, and facilitate the operation, an integrated EMC device with a split design was fabricated. With the proposed EMC device, the signals of aminoglycosides were enhanced by a factor of 5-85 without affecting the separation efficiency or elution order. For the analysis of aminoglycosides in bovine milk, the proposed approach demonstrates a sensitivity that is at least 10 times below the maximum residue limits set by most countries. PMID:27497008

  6. Electrophoretic deposition of CdS coatings and their photocatalytic activities in the degradation of tetracycline antibiotic

    NASA Astrophysics Data System (ADS)

    Vázquez, A.; Hernández-Uresti, D. B.; Obregón, S.

    2016-11-01

    The photocatalytic activities of CdS coatings formed by electrophoretic deposition (EPD) were evaluated through the photodegradation of an antibiotic, tetracycline. First, CdS nanoparticles were synthesized under microwave irradiation of aqueous solutions containing the cadmium and sulfur precursors at stoichiometric amounts and by using trisodium citrate as stabilizer. Microwave irradiation was carried out in a conventional microwave oven at 2.45 GHz and 1650 W of nominal power, for 60 s. The CdS nanoparticles were characterized by UV-vis spectrophotometry, photoluminescence and X-ray diffraction. Electrophoretic deposition parameters were 300 mV, 600 mV and 900 mV of applied voltage between aluminum plates separated by 1 cm. The fractal dimensions of the surfaces were evaluated by atomic force microscopy and correlated to the morphological and topographic characteristics of the coatings. The photocatalytic activity of the CdS coatings was investigated by means the photodegradation of the tetracycline antibiotic under simulated sunlight irradiation. According to the results, the photoactivity of the coatings directly depends on the concentration of the precursors and the applied voltage during the deposition. The material obtained at 600 mV showed the best photocatalytic behavior, probably due to its physical properties, such as optimum load and suitable aggregate size.

  7. Intrinsically bent DNA flanks both sides of an RNA polymerase I transcription start site. Both regions display novel electrophoretic mobility.

    PubMed

    Schroth, G P; Siino, J S; Cooney, C A; Th'ng, J P; Ho, P S; Bradbury, E M

    1992-05-15

    We have identified two intrinsically bent regions of DNA which flank the transcription start site of the rRNA gene from Physarum polycephalum. DNA fragments from both regions were analyzed by circular permutation polyacrylamide gel electrophoresis assay and computer modeling. Both types of analysis indicate that one fragment contains a relatively simple bend centered about 160 base pairs (bp) upstream of the transcription start site while the other fragment contains multiple bends, the most prominent of which is centered about 150 bp downstream of the start site. According to both gel mobilities and computer modeling we estimate that the net bending in each is about 45 degrees. These fragments were studied in detail by varying parameters of electrophoresis that are known to affect bending. Previous work indicates that anomalous mobility should decrease when temperature or ethidium bromide concentration is increased, whereas anomalous mobility should increase when polyacrylamide gel percentage is increased. The anomalous mobility of both fragments decreases as temperature is raised from 4 to 65 degrees C, although the bent structure centered at -160 bp is more temperature labile than the bend at +150 bp. Strikingly different behavior was observed for the two fragments as the polyacrylamide concentrations was varied. As polyacrylamide concentrations are increased from 6 to 10%, the anomalous mobility of the bend centered at -160 bp increases while that of the bend centered at +150 bp decreases. The bend centered at +150 bp is "straightened" at all ethidium concentrations tested. In sharp contrast and unexpectedly, the anomalous migration of the bend centered at -160 bp increases dramatically in 0.1 micrograms/ml ethidium bromide. Many of the mobility differences we observe suggest that the two regions studied represent structurally distinct forms of bent DNA. The location of these strongly bent regions on either side of a RNA polymerase I transcription start site

  8. Electrophoretic Focusing

    NASA Technical Reports Server (NTRS)

    Snyder, Robert S.

    2001-01-01

    Electrophoretic focusing is a new method of continuous flow electrophoresis that introduces precision flow control to achieve high resolution separations. The electric field is applied perpendicular to an incoming sample lamina and buffer but also perpendicular to the broad faces of the thin rectangular chamber. A uniform fluid cross-flow then enters and exits the separation chamber through the same broad faces which are porous. A balance is achieved by adjusting either the electric field or the cross-flow so the desired sample fraction with its specific migration velocity encounters an opposing flow of the same velocity. Applying an electric field transverse to the incoming sample lamina and opposing this field with a carefully configured buffer flow, a sample constituent can be selected and focused into a narrow stream for subsequent analysis. Monotonically changing either electric field or buffer cross-flow will yield a scan of all constituents of the sample. Stopping the scan increases the collection time for minor constituents to improve their analysis. Using the high voltage gradients and/or cross-flow to rapidly deflect extraneous sample through the porous screens and into either of the side (purge) chambers, the selected sample is focused in the center plane of the separation chamber and collected without contact or interaction with the separation chamber walls. Results will be presented on the separation of a range of materials including dyes, proteins, and monodisperse polystyrene latexes. Sources of sample dispersion inherent in other electrokinetic techniques will be shown to be negligible for a variety of sample concentrations, buffer properties and operating conditions.

  9. High Sensitivity Method to Estimate Distribution of Hyaluronan Molecular Sizes in Small Biological Samples Using Gas-Phase Electrophoretic Mobility Molecular Analysis

    PubMed Central

    Do, Lan; Dahl, Christen P.; Kerje, Susanne; Hansell, Peter; Mörner, Stellan; Lindqvist, Ulla; Engström-Laurent, Anna; Larsson, Göran; Hellman, Urban

    2015-01-01

    Hyaluronan is a negatively charged polydisperse polysaccharide where both its size and tissue concentration play an important role in many physiological and pathological processes. The various functions of hyaluronan depend on its molecular size. Up to now, it has been difficult to study the role of hyaluronan in diseases with pathological changes in the extracellular matrix where availability is low or tissue samples are small. Difficulty to obtain large enough biopsies from human diseased tissue or tissue from animal models has also restricted the study of hyaluronan. In this paper, we demonstrate that gas-phase electrophoretic molecular mobility analyzer (GEMMA) can be used to estimate the distribution of hyaluronan molecular sizes in biological samples with a limited amount of hyaluronan. The low detection level of the GEMMA method allows for estimation of hyaluronan molecular sizes from different parts of small organs. Hence, the GEMMA method opens opportunity to attain a profile over the distribution of hyaluronan molecular sizes and estimate changes caused by disease or experimental conditions that has not been possible to obtain before. PMID:26448761

  10. Sizing up large protein complexes by electrospray ionisation-based electrophoretic mobility and native mass spectrometry: morphology selective binding of Fabs to hepatitis B virus capsids.

    PubMed

    Bereszczak, Jessica Z; Havlik, Marlene; Weiss, Victor U; Marchetti-Deschmann, Martina; van Duijn, Esther; Watts, Norman R; Wingfield, Paul T; Allmaier, Guenter; Steven, Alasdair C; Heck, Albert J R

    2014-02-01

    The capsid of hepatitis B virus (HBV) is a major viral antigen and important diagnostic indicator. HBV capsids have prominent protrusions ('spikes') on their surface and are unique in having either T = 3 or T = 4 icosahedral symmetry. Mouse monoclonal and also human polyclonal antibodies bind either near the spike apices (historically the 'α-determinant') or in the 'floor' regions between them (the 'β-determinant'). Native mass spectrometry (MS) and gas-phase electrophoretic mobility molecular analysis (GEMMA) were used to monitor the titration of HBV capsids with the antigen-binding domain (Fab) of mAb 3120, which has long defined the β-determinant. Both methods readily distinguished Fab binding to the two capsid morphologies and could provide accurate masses and dimensions for these large immune complexes, which range up to ~8 MDa. As such, native MS and GEMMA provide valuable alternatives to a more time-consuming cryo-electron microscopy analysis for preliminary characterisation of virus-antibody complexes.

  11. Nano electrospray gas-phase electrophoretic mobility molecular analysis (nES GEMMA) of liposomes: applicability of the technique for nano vesicle batch control

    PubMed Central

    Weiss, Victor U.; Urey, Carlos; Gondikas, Andreas; Golesne, Monika; Friedbacher, Gernot; von der Kammer, Frank; Hofmann, Thilo; Andersson, Roland; Marko-Varga, György; Marchetti-Deschmann, Martina

    2016-01-01

    Liposomes are biodegradable nanoparticle vesicles consisting of a lipid bilayer encapsulating an aqueous core. Entrapped cargo material is shielded from the extra-vesicular medium and sustained release of encapsulated material can be achieved. However, application of liposomes as nano-carriers demands their characterization concerning size and size distribution, particle-number concentration, occurrence of vesicle building blocks in solution and determination of the resulting vesicle encapsulation capacity. These questions can be targeted via gas-phase electrophoretic mobility molecular analysis (GEMMA) based on a nano electrospray (nES) charge-reduction source. This instrument separates single-charged nanoparticles in the gas-phase according to size in a high-laminar sheath-flow by means of an orthogonal, tunable electric field. nES GEMMA analysis enables to confirm liposome integrity after passage through the instrument (in combination with atomic force microscopy) as well as to exclude vesicle aggregation. Additionally, nanoparticle diameters at peak apexes and size distribution data are obtained. Differences of hydrodynamic and dry particle diameter values, as well as the effect of number- and mass-based concentration data analysis on obtained liposome diameters are shown. Furthermore, the repeatability of liposome preparation is studied, especially upon incorporation of PEGylated lipids in the bilayer. Finally, the instruments applicability to monitor mechanical stress applied to vesicles is demonstrated. PMID:27549027

  12. Screening for Functional Non-coding Genetic Variants Using Electrophoretic Mobility Shift Assay (EMSA) and DNA-affinity Precipitation Assay (DAPA).

    PubMed

    Miller, Daniel E; Patel, Zubin H; Lu, Xiaoming; Lynch, Arthur T; Weirauch, Matthew T; Kottyan, Leah C

    2016-01-01

    Population and family-based genetic studies typically result in the identification of genetic variants that are statistically associated with a clinical disease or phenotype. For many diseases and traits, most variants are non-coding, and are thus likely to act by impacting subtle, comparatively hard to predict mechanisms controlling gene expression. Here, we describe a general strategic approach to prioritize non-coding variants, and screen them for their function. This approach involves computational prioritization using functional genomic databases followed by experimental analysis of differential binding of transcription factors (TFs) to risk and non-risk alleles. For both electrophoretic mobility shift assay (EMSA) and DNA affinity precipitation assay (DAPA) analysis of genetic variants, a synthetic DNA oligonucleotide (oligo) is used to identify factors in the nuclear lysate of disease or phenotype-relevant cells. For EMSA, the oligonucleotides with or without bound nuclear factors (often TFs) are analyzed by non-denaturing electrophoresis on a tris-borate-EDTA (TBE) polyacrylamide gel. For DAPA, the oligonucleotides are bound to a magnetic column and the nuclear factors that specifically bind the DNA sequence are eluted and analyzed through mass spectrometry or with a reducing sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) followed by Western blot analysis. This general approach can be widely used to study the function of non-coding genetic variants associated with any disease, trait, or phenotype. PMID:27585267

  13. Electrophoretic mobility of cell nuclei (EMN index) as a biomarker of the biological aging process: Considering the association between EMN index and age.

    PubMed

    Czapla, Z; McPhail, S M

    2015-12-01

    The present study examined whether a specific property of cell microstructures may be useful as a biomarker of aging. Specifically, the association between age and changes of cellular structures reflected in electrophoretic mobility of cell nuclei index (EMN index) values across the adult lifespan was examined. This report considers findings from cross sections of females (n=1273) aged 18-98 years, and males (n=506) aged 19-93 years. A Biotest apparatus was used to perform intracellular microelectrophoresis on buccal epithelial cells collected from each individual. EMN index was calculated on the basis of the number of epithelial cells with mobile nuclei in reference to the cells with immobile nuclei per 100cells. Regression analyses indicated a significant negative association between EMN index value and age for men (r=-0.71, p<0.001) and women (r=-0.60, p<0.001); demonstrating a key requirement that must be met by a biomarker of aging. The strength of association observed between EMN index and age for both men and women was encouraging and supports the potential use of EMN index for determining a biological age of an individual (or a group). In this study, a new attempt of complex explanation of cellular mechanisms contributing to age related changes of the EMN index was made. In this study, a new attempt of complex explanation of cellular mechanisms contributing to age related changes of the EMN index was made. EMN index has demonstrated potential to meet criteria proposed for biomarkers of aging and further investigations are necessary.

  14. Properties of poly(styrene/alpha-tert-butoxy-omega-vinylbenzyl-polyglycidol) microspheres suspended in water. Effect of sodium chloride and temperature on particle diameters and electrophoretic mobility.

    PubMed

    Basinska, Teresa; Slomkowski, Stanislaw; Kazmierski, Slawomir; Chehimi, Mohamed M

    2008-08-19

    Hydrodynamic and electrophoretic properties of core-shell poly(styrene/alpha- tert-butoxy-omega-vinylbenzyl-polyglycidol) (P(S/PGL)) microspheres suspended in water are described. The microspheres were obtained by surfactant-free emulsion copolymerization of styrene and alpha- tert-butoxy-omega-vinylbenzyl-polyglycidol macromonomer ( M n = 2800, M w/ M n = 1.05). The process yielded microspheres with number average diameter D n = 270 nm and with low diameter dispersity index D w/ D n = 1.01. Shells of P(S/PGL) microspheres were enriched in polyglycidol. Molar fraction of polyglycidol monomeric units in the shells (determined by X-ray photoelectron spectroscopy) was equal to 0.34, which is much higher than the average molar fraction of polyglycidol monomeric units in whole particles of 0.048. Influences of NaCl concentration and temperature on P(S/PGL) microsphere diameters and on their electrophoretic mobility were investigated. It was found that hydrodynamic diameter of P(S/PGL) microspheres, determined by photon correlation spectroscopy, decreased significantly when temperature did exceed a certain value (transition temperature, T t). It has been found that the decrease is more pronounced for higher concentrations of NaCl in the medium. For microspheres suspended in 10 (-1) M NaCl, the hydrodynamic diameter decreased by 8% whereas for the same particles in pure water the diameter decreased by 5.2%. The process of shrinkage was fully reversible. Values of T t for P(S/PGL) microspheres were lower for higher concentrations of NaCl. Adjustment of salt concentration allowed controlling T t in a range from 44.4 to 49.9 degrees C. 13C NMR relaxation time measurements (T 1) for carbon atoms in polyglycidol macromonomer revealed that T 1 did increase with increasing temperature (in temperature range from 25 to 75 degrees C) indicating higher motion of chains at higher temperature. Addition of NaCl did not induce a substantial change of T 1 in the mentioned temperature

  15. Effects of non-equilibrium association-dissociation processes in the dynamic electrophoretic mobility and dielectric response of realistic salt-free concentrated suspensions.

    PubMed

    Carrique, Félix; Ruiz-Reina, Emilio; Lechuga, Luis; Arroyo, Francisco J; Delgado, Ángel V

    2013-12-01

    Electrokinetic investigations in nanoparticle suspensions in aqueous media are most often performed assuming that the liquid medium is a strong electrolyte solution with specified concentration. The role of the ions produced by the process of charging the surfaces of the particles is often neglected or, at most, the concentrations of such ions are estimated in some way and added to the concentrations of the ions in the externally prepared solution. The situation here considered is quite different: no electrolyte is dissolved in the medium, and ideally only the counterions stemming from the particle charging are assumed to be in solution. This is the case of so-called salt-free systems. With the aim of making a model for such kind of dispersions as close to real situations as possible, it was previously found to consider the unavoidable presence of H(+) and OH(-) coming from water dissociation, as well as the (almost unavoidable) ions stemming from the dissolution of atmospheric CO2. In this work, we extend such approach by considering that the chemical reactions involved in dissociation and recombination of the (weak) electrolytes in solution must not necessarily be in equilibrium conditions (equal rates of forward and backward reactions). To that aim, we calculate the frequency spectra of the electric permittivity and dynamic electrophoretic mobility of salt-free suspensions considering realistic non-equilibrium conditions, using literature values for the rate constants of the reactions. Four species are linked by such reactions, namely H(+) (from water, from the--assumed acidic--groups on the particle surfaces, and from CO2 dissolution), OH(-) (from water), HCO3(-) and H2CO3 (again from CO2). A cell model is used for the calculations, which are extended to arbitrary values of the surface charge, the particle size, and particle volume fraction, in a wide range of the field frequency ω. Both approaches predict a high frequency relaxation of the counterion

  16. Effects of non-equilibrium association-dissociation processes in the dynamic electrophoretic mobility and dielectric response of realistic salt-free concentrated suspensions.

    PubMed

    Carrique, Félix; Ruiz-Reina, Emilio; Lechuga, Luis; Arroyo, Francisco J; Delgado, Ángel V

    2013-12-01

    Electrokinetic investigations in nanoparticle suspensions in aqueous media are most often performed assuming that the liquid medium is a strong electrolyte solution with specified concentration. The role of the ions produced by the process of charging the surfaces of the particles is often neglected or, at most, the concentrations of such ions are estimated in some way and added to the concentrations of the ions in the externally prepared solution. The situation here considered is quite different: no electrolyte is dissolved in the medium, and ideally only the counterions stemming from the particle charging are assumed to be in solution. This is the case of so-called salt-free systems. With the aim of making a model for such kind of dispersions as close to real situations as possible, it was previously found to consider the unavoidable presence of H(+) and OH(-) coming from water dissociation, as well as the (almost unavoidable) ions stemming from the dissolution of atmospheric CO2. In this work, we extend such approach by considering that the chemical reactions involved in dissociation and recombination of the (weak) electrolytes in solution must not necessarily be in equilibrium conditions (equal rates of forward and backward reactions). To that aim, we calculate the frequency spectra of the electric permittivity and dynamic electrophoretic mobility of salt-free suspensions considering realistic non-equilibrium conditions, using literature values for the rate constants of the reactions. Four species are linked by such reactions, namely H(+) (from water, from the--assumed acidic--groups on the particle surfaces, and from CO2 dissolution), OH(-) (from water), HCO3(-) and H2CO3 (again from CO2). A cell model is used for the calculations, which are extended to arbitrary values of the surface charge, the particle size, and particle volume fraction, in a wide range of the field frequency ω. Both approaches predict a high frequency relaxation of the counterion

  17. Experimental test of new theoretical models for the electrokinetic properties of biological membranes. The effect of UO/sup 2 + +/ and tetracaine on the electrophoretic mobility of bilayer membranes and human erythrocytes

    SciTech Connect

    Pasquale, L.; Winiski, A.; Oliva, C.; Vaio, G.; McLaughlin, S.

    1986-12-01

    For a large smooth particle with charges at the surface, the electrophoretic mobility is proportional to the zeta potential, which is related to the charge density by the Gouy-Chapman theory of the diffuse double layer. This classical model adequately describes the dependence of the electrophoretic mobility of phospholipid vesicles on charge density and salt concentration, but it is not applicable to most biological cells, for which new theoretical models have been developed. We tested these new models experimentally by measuring the effect of UO/sup 2 + +/ on the electrophoretic mobility of model membranes and human erythrocytes in 0.15 M NaCl at pH 5. We used UO/sup 2 + +/ for these studies because it should adsorb specifically to the bilayer surface of the erythrocyte and should not change the density of fixed charges in the glycocalyx. Our experiments demonstrate that it forms high-affinity complexes with the phosphate groups of several phospholipids in a bilayer but does not bind significantly to sialic acid residues. As observed previously, UO/sup 2 + +/ adsorbs strongly to egg phosphatidylcholine (PC) vesicles: 0.1 mM UO/sup 2 + +/ changes the zeta potential of PC vesicles from 0 to +40 mV. It also has a large effect on the electrophoretic mobility of vesicles formed from mixtures of PC and the negative phospholipid phosphatidylserine (PS): 0.1 mM UO/sup 2 + +/ changes the zeta potential of PC/PS vesicles (10 mol % PS) from -13 to +37 mV. In contrast, UO/sup 2 + +/ has only a small effect on the electrophoretic mobility of either vesicles formed from mixtures of PC and the negative ganglioside GM1 or erythrocytes: 0.1 mM UO/sup 2 + +/ changes the apparent zeta potential of PC/GM1 vesicles (17 mol % GM1) from -11 to +5 mV and the apparent zeta potential of erythrocytes from -12 to -4 mV.

  18. Quantifying the Heterogeneity of Chemical Structures in Complex Charged Polymers through the Dispersity of Their Distributions of Electrophoretic Mobilities or of Compositions.

    PubMed

    Thevarajah, Joel J; Sutton, Adam T; Maniego, Alison R; Whitty, Elizabeth G; Harrisson, Simon; Cottet, Hervé; Castignolles, Patrice; Gaborieau, Marianne

    2016-02-01

    The complexity of synthetic and natural polymers used in industrial and medical applications is expanding; thus, it becomes increasingly important to improve and develop methods for their molecular characterization. Free-solution capillary electrophoresis is a robust technique for the separation and characterization of both natural and synthetic complex charged polymers. In the case of polyelectrolytes, free-solution capillary electrophoresis is in the "critical conditions" (CE-CC): it allows their separation by factors other than molar mass for molar masses typically higher than 20000 g/mol. This method is thus complementary to size-exclusion chromatography (SEC). SEC is widely used to determine molar mass distributions and their dispersities. Utilizing CE-CC, an analogous calculation of dispersity based on the distributions of electrophoretic mobilities was derived and the heterogeneity of composition or branching in different polysaccharides or synthetic polymers was obtained in a number of experimental cases. Calculations are based on a ratio of moments and could therefore be compared to simulations of polymerization processes, in analogy to the work performed on molar mass distributions. Among four possible types of dispersity, the most precise values were obtained with the calculation analogous with the dispersity of molar mass distribution Mw/Mn. In addition, the dispersity value allows conclusions based on a single value: the closer the dispersity is to 1, the more homogeneous the polymer is in terms of composition or branching. This approach allows the analysis of dispersity of important molecular attributes of polymers other than molar mass and aims at improving the overall molecular characterization of both synthetic and natural polymers. The dispersity can also be monitored online while performing a chemical reaction within the CE instrument.

  19. Instrument and method to determine the electrophoretic mobility of nanoparticles and proteins by combining electrical and flow field-flow fractionation.

    PubMed

    Johann, Christoph; Elsenberg, Stephan; Schuch, Horst; Rösch, Ulrich

    2015-04-21

    A new FFF method is presented which combines asymmetrical flow-FFF (AF4) and electrical FFF (ElFFF) in one channel to electrical asymmetrical flow-FFF (EAF4) to overcome the restrictions of pure ElFFF. It allows for measuring electrophoretic mobility (μ) as a function of size. The method provides an absolute value and does not require calibration. Results of μ for two particle standards are in good agreement with values determined by phase analysis light scattering (PALS). There is no requirement for low ionic strength carriers with EAF4. This overcomes one of the main limitations of ElFFF, making it feasible to measure proteins under physiological conditions. EAF4 has the capability to determine μ for individual populations which are resolved into separate peaks. This is demonstrated for a mixture of three polystyrene latex particles with different sizes as well as for the monomer and dimer of BSA and an antibody. The experimental setup consists of an AF4 channel with added electrodes; one is placed beneath the frit at the bottom wall and the other covers the inside of the upper channel plate. This design minimizes contamination from the electrolysis reactions by keeping the particles distant from the electrodes. In addition the applied voltage range is low (1.5-5 V), which reduces the quantity of gaseous electrolysis products below a threshold that interferes with the laminar flow profile or detector signals. Besides measuring μ, the method can be useful to improve the separation between sample components compared to pure flow-FFF. For two proteins (BSA and a monoclonal antibody), enhanced resolution of the monomer and dimer is achieved by applying an electric field.

  20. Analysis of Mutant SOD1 Electrophoretic Mobility by Blue Native Gel Electrophoresis; Evidence for Soluble Multimeric Assemblies

    PubMed Central

    Brown, Hilda H.; Borchelt, David R.

    2014-01-01

    Mutations in superoxide dismutase 1 (SOD1) cause familial forms of amyotrophic lateral sclerosis (fALS). Disease causing mutations have diverse consequences on the activity and half-life of the protein, ranging from complete inactivity and short half-life to full activity and long-half-life. Uniformly, disease causing mutations induce the protein to misfold and aggregate and such aggregation tendencies are readily visualized by over-expression of the proteins in cultured cells. In the present study we have investigated the potential of using immunoblotting of proteins separated by Blue-Native gel electrophoresis (BNGE) as a means to identify soluble multimeric forms of mutant protein. We find that over-expressed wild-type human SOD1 (hSOD1) is generally not prone to form soluble high molecular weight entities that can be separated by BNGE. For ALS mutant SOD1, we observe that for all mutants examined (A4V, G37R, G85R, G93A, and L126Z), immunoblots of BN-gels separating protein solubilized by digitonin demonstrated varied amounts of high molecular weight immunoreactive entities. These entities lacked reactivity to ubiquitin and were partially dissociated by reducing agents. With the exception of the G93A mutant, these entities were not reactive to the C4F6 conformational antibody. Collectively, these data demonstrate that BNGE can be used to assess the formation of soluble multimeric assemblies of mutant SOD1. PMID:25121776

  1. Candies to Dye For: Cooperative, Open-Ended Student Activities To Promote Understanding of Electrophoretic Fractionation.

    ERIC Educational Resources Information Center

    Emry, Randall; Curtright, Robert D.; Wright, Jonathan; Markwell, John

    2000-01-01

    Introduces electrophoresis activities developed for chemistry and biology courses in which students identify the food, drug, and cosmetic identity of the food dyes used in the coating of candies. (YDS)

  2. Electrophoretically active sol-gel processes to backfill, seal, and/or densify porous, flawed, and/or cracked coatings on electrically conductive material

    DOEpatents

    Panitz, J.K.; Reed, S.T.; Ashley, C.S.; Neiser, R.A.; Moffatt, W.C.

    1999-07-20

    Electrophoretically active sol-gel processes to fill, seal, and/or density porous, flawed, and/or cracked coatings on electrically conductive substrates. Such coatings may be dielectrics, ceramics, or semiconductors and, by the present invention, may have deposited onto and into them sol-gel ceramic precursor compounds which are subsequently converted to sol-gel ceramics to yield composite materials with various tailored properties. 6 figs.

  3. Electrophoretically active sol-gel processes to backfill, seal, and/or densify porous, flawed, and/or cracked coatings on electrically conductive material

    DOEpatents

    Panitz, Janda K.; Reed, Scott T.; Ashley, Carol S.; Neiser, Richard A.; Moffatt, William C.

    1999-01-01

    Electrophoretically active sol-gel processes to fill, seal, and/or density porous, flawed, and/or cracked coatings on electrically conductive substrates. Such coatings may be dielectrics, ceramics, or semiconductors and, by the present invention, may have deposited onto and into them sol-gel ceramic precursor compounds which are subsequently converted to sol-gel ceramics to yield composite materials with various tailored properties.

  4. Capillary electrophoretic behaviors of pharmacologically active xanthones from Securidaca inappendiculata with beta-cyclodextrin as a buffer additive.

    PubMed

    Bo, Tao; Huang, Yongfa; Yang, Xuedong; Li, Ke An; Liu, Huwei; Xu, Lizhen

    2003-04-01

    The capillary electrophoretic (CE) behaviors of ten xanthones in the presence of beta-cyclodextrin (CD) are investigated, and apparent analyte-selector binding constants between beta-CD and the xanthones in the CE running buffer are calculated to elucidate the migration order. Also, the separation selectivity with beta-CD additive is compared with that of sulfated beta-CD additive. It is indicated that beta-CD can greatly change the separation selectivity of xanthones, and the electrophoretic behaviors of xanthones are rather different when using beta-CD from that when using sulfated beta-CD as an additive. PMID:12803804

  5. Staining electrophoretic gels for laccase and peroxidase activity using 1,8-diaminonaphthalene.

    PubMed

    Hoopes, J T; Dean, J F

    2001-06-01

    A new chromogenic substrate for laccases and peroxidases, 1,8-diaminonapthalene, was used to detect phenoloxidase activity in gels after SDS-PAGE. This substrate has several advantages over other widely used phenoloxidase stains in that it is inexpensive, and the oxidized product has both high molar absorptivity and very low solubility. Furthermore, neither the substrate nor the product is known to have toxicity problems of the type associated with many other phenoloxidase stains. The sensitivity of detection using 1,8-diaminonapthalene was comparable to that obtained using the most sensitive stains commonly used for phenoloxidases, e.g., 3,3-diaminobenzidine, and was close to that attainable for protein detection using silver staining. Zymograms developed with 1,8-diaminonapthalene can be used with video densitometry to monitor the specific enzymatic activity of phenoloxidases during enzyme purification. PMID:11373084

  6. Research on Mobile Learning Activities Applying Tablets

    ERIC Educational Resources Information Center

    Kurilovas, Eugenijus; Juskeviciene, Anita; Bireniene, Virginija

    2015-01-01

    The paper aims to present current research on mobile learning activities in Lithuania while implementing flagship EU-funded CCL project on application of tablet computers in education. In the paper, the quality of modern mobile learning activities based on learning personalisation, problem solving, collaboration, and flipped class methods is…

  7. Properties of electrophoretic fractions of human embryonic kidney cells separated on space shuttle flight STS-8

    NASA Technical Reports Server (NTRS)

    Morrison, D. R.; Lewis, M. L.; Barlow, G. H.; Todd, P. W.; Kunze, M. E.; Sarnoff, B. E.; Li, Z. K.

    1985-01-01

    Suspensions of cultured primary human embryonic kidney cells were subjected to continuous flow electrophoresis on Space Shuttle flight STS-8. The objectives of the experiments were to obtain electrophoretically separated fractions of the original cell populations and to test these fractions for the amount and kind of urokinase (a kidney plasminogen activator that is used medically for digesting blood clots), the morphologies of cells in the individual fractions, and their cellular electrophoretic mobilities after separation and subsequent proliferation. Individual fractions were successfully cultured after return from orbit, and they were found to differ substantially from one another and from the starting sample with respect to all of these properties.

  8. Surface modification of inorganic black particles for electrophoretic display

    NASA Astrophysics Data System (ADS)

    Kim, Sang Deuk; Ahn, Woo Jin; Choi, Hyoung Jin

    2014-11-01

    Inorganic black particles (Black 444) were modified with poly(methyl methacrylate) as a shell material by using dispersion polymerization to improve their dispersion stability in a medium oil for electrophoretic display applications. They were also positively charged with vinylimidazole to enhance their electrophoretic mobility. The morphology and the shape of the composite particles were characterized by using scanning electron microscopy. The thermal properties and the chemical structure of the samples were examined by using thermogravimetric analysis and Fourier-transform infrared spectroscopy, respectively. In addition, the electrophoretic mobility and the zeta-potential of the black444/PMMA/vinylimidazole particles in a dielectric fluid were measured by using optical microscopy and electrophoretic light scattering. With increasing positive charge, the black444/PMMA/vinylimidazole particles showed improved electrophoretic characteristics compared to pristine Black 444.

  9. Urokinase production by electrophoretically separated cultured human embryonic kidney cells

    NASA Technical Reports Server (NTRS)

    Kunze, M. E.; Plank, L. D.; Giranda, V.; Sedor, K.; Todd, P. W.

    1985-01-01

    Urokinase is a plasminogen activator found in urine. Relatively pure preparations have been tested in Europe, Japan and the United States for the treatment of deep vein thrombosis and other dangerous blood clots. Human embryonic kidney cell cultures have been found to produce urokinase at much higher concentrations, but less than 5% of the cells in typical cultures are producers. Since human diploid cells become senescent in culture the selection of clones derived from single cells will not provide enough material to be useful, so a bulk purification method is needed for the isolation of urokinase producing cell populations. Preparative cell electrophoresis was chosen as the method, since evidence exists that human embryonic cell cultures are richly heterogeneous with respect to electrophoretic mobility, and preliminary electrophoretic separations on the Apollo-Soyuz space flight produced cell populations that were rich in urokinase production. Similarly, erythropoietin is useful in the treatment of certain anemias and is a kidney cell duct, and electrophoretically enriched cell populations producing this product have been reported. Thus, there is a clear need for diploid human cells that produce these products, and there is evidence that such cells should be separable by free-flow cell electrophoresis.

  10. Comparison of experimental vision performance testing techniques, including the implementation of an active matrix electrophoretic ink display

    NASA Astrophysics Data System (ADS)

    Swinney, Mathew W.; Marasco, Peter L.; Heft, Eric L.

    2007-04-01

    Standard black and white printed targets have been used for numerous vision related experiments, and are ideal with respect to contrast and spectral uniformity in the visible and near-infrared (NIR) regions of the electromagnetic (EM) spectrum. However, these targets lack the ability to refresh, update, or perform as a real-time, dynamic stimulus. This impacts their ability to be used in various standard vision performance measurement techniques. Emissive displays, such as a LCD's, possess some of the attributes printed targets lack, but come with a disadvantage of their own: LCD's lack the spectral uniformity of printed targets, making them of debatable value for presenting test targets in the near and short wave infrared regions of the spectrum. Yet a new option has recently become viable that may retain favorable attributes of both of the previously mentioned alternatives. The electrophoretic ink display is a dynamic, refreshable, and easily manipulated display that performs much like printed targets with respect to spectral uniformity. This paper will compare and contrast the various techniques that can be used to measure observer visual performance through night vision devices and imagers - focusing on the visible to infrared region of the EM spectrum. Furthermore, it will quantify the electrophoretic ink display option, determining its advantages and situations that it would be best suited for.

  11. Arylsulfatase A: Relationship of genotype to variant electrophoretic properties

    SciTech Connect

    Park, D.S.; Poretz, R.D.; Ricketts, M.H.; Manowitz, P.

    1996-04-01

    Previous work has shown that specific electrophoretic variants of arylsulfatase A occur more frequently among alcoholic patients than among psychiatric and normal controls. The present study sequenced the gene for two of these electrophoretic variants, IIIa and IIIb. Both contain an A-to-G transition corresponding to substitution of Asn{sub 350} by Ser, with the resulting loss of an N -glycosylation site. The difference in electrophoretic mobility of their gene products is due to a mutation in the IIIb gene resulting in the replacement of Arg{sub 496} by His. Evidence is presented that individuals posessing either of two other electrophoretic variants, Va and Vb, are heterozygous for a normal ASA allele and either a IIIa or IIIb allele, respectively. Thus, the relationship between the phenotype of the electrophoretic banding patterns, IIIa, IIIb, Va, and Vb, and their corresponding genotypes has been elucidated. 18 refs., 5 figs., 1 tab.

  12. Analyses of gonococcal H8 antigen. Surface location, inter- and intrastrain electrophoretic heterogeneity, and unusual two-dimensional electrophoretic characteristics.

    PubMed

    Hitchcock, P J; Hayes, S F; Mayer, L W; Shafer, W M; Tessier, S L

    1985-12-01

    The H8 protein is a surface-exposed antigen that is found, among members of the Neisseria genus, primarily on pathogenic species. In this study, the surface exposure of H8 was reassessed by four techniques. Results of slide agglutination, indirect fluorescent antibody binding, absorption of sera with whole gonococci, and immune electron microscopy all confirmed the presence of H8 in the outer membrane. The degree to which protein A-gold-labeled monoclonal antibodies bound to H8 was marked, and suggested that this antigen was present in abundant amounts in the outer membrane. Also in this study, the electrophoretic heterogeneity of this common surface antigen was examined. Because H8 stains poorly, electrophoretic mobility was assessed using polyclonal antibodies and a monoclonal antibody that recognizes a common H8 epitope. H8 was analyzed with respect to protein I, lipopolysaccharide (LPS), and pilus and opacity phenotypic variation; results confirmed that heterogeneity of Mr was the rule among strains (21 were examined), however, the variability in Mr was independent of protein I or LPS Mr. In one strain (FA1090), the heterogeneity of H8 was examined among 10 piliation/opacity variants; the H8 (and LPS) Mr was identical in all variants; similar data were generated in strains JS3 and JS1. The electrophoretic mobility of H8 was altered in serum-resistant and neutrophil enzyme-resistant gonococci compared to the sensitive gonococci. Some of the unusual electrophoretic migration characteristics of the antigen were also examined. H8 formed a unique mushroom-shaped band in one-dimensional gels; in a two-dimensional electrophoresis system, the antigen migrated aberrantly, very similarly to LPS. Also seen in the two-dimensional electrophoresis profile were multimers of the H8 antigen; in strain JS3 (Mr 23,500), these migrated at 43,600, 86,000, and greater than 150,000. In other strains, the Mr of the multimers differed depending upon the Mr of the monomer. The two

  13. Mobile robotics activities in DOE laboratories

    NASA Astrophysics Data System (ADS)

    Lujan, Ron; Harbour, Jerry; Feddema, John; Bailey, Sharon; Barhen, Jacob; Reister, David

    2005-05-01

    This paper will briefly outline major activities in Department of Energy (DOE) Laboratories focused on mobile platforms, both Unmanned Ground Vehicles (UGV"s) as well as Unmanned Air Vehicles (UAV's). The activities will be discussed in the context of the science and technology construct used by the DOE Technology Roadmap for Robotics and Intelligent Machines (RIM)1 published in 1998; namely, Perception, Reasoning, Action, and Integration. The activities to be discussed span from research and development to deployment in field operations. The activities support customers in other agencies. The discussion of "perception" will include hyperspectral sensors, complex patterns discrimination, multisensor fusion and advances in LADAR technologies, including real-world perception. "Reasoning" activities to be covered include cooperative controls, distributed systems, ad-hoc networks, platform-centric intelligence, and adaptable communications. The paper will discuss "action" activities such as advanced mobility and various air and ground platforms. In the RIM construct, "integration" includes the Human-Machine Integration. Accordingly the paper will discuss adjustable autonomy and the collaboration of operator(s) with distributed UGV's and UAV's. Integration also refers to the applications of these technologies into systems to perform operations such as perimeter surveillance, large-area monitoring and reconnaissance. Unique facilities and test beds for advanced mobile systems will be described. Given that this paper is an overview, rather than delve into specific detail in these activities, other more exhaustive references and sources will be cited extensively.

  14. GalileoMobile: Astronomical activities in schools

    NASA Astrophysics Data System (ADS)

    Dasi Espuig, Maria; Vasquez, Mayte; Kobel, Philippe

    GalileoMobile is an itinerant science education initiative run on a voluntary basis by an international team of astronomers, educators, and science communicators. Our team's main goal is to make astronomy accessible to schools and communities around the globe that have little or no access to outreach actions. We do this by performing teacher workshops, activities with students, and donating educational material. Since the creation of GalileoMobile in 2008, we have travelled to Chile, Bolivia, Peru, India, and Uganda, and worked with 56 schools in total. Our activities are centred on the GalileoMobile Handbook of Activities that comprises around 20 astronomical activities which we adapted from many different sources, and translated into 4 languages. The experience we gained in Chile, Bolivia, Peru, India, and Uganda taught us that (1) bringing experts from other countries was very stimulating for children as they are naturally curious about other cultures and encourages a collaboration beyond borders; (2) high-school students who were already interested in science were always very eager to interact with real astronomers doing research to ask for career advice; (3) inquiry-based methods are important to make the learning process more effective and we have therefore, re-adapted the activities in our Handbook according to these; (4) local teachers and university students involved in our activities have the potential to carry out follow-up activities, and examples are those from Uganda and India.

  15. Mobile Robotics Activities in DOE Laboratories

    SciTech Connect

    Ron Lujan; Jerry Harbour; John T. Feddema; Sharon Bailey; Jacob Barhen; David Reister

    2005-03-01

    This paper will briefly outline major activities in Department of Energy (DOE) Laboratories focused on mobile platforms, both Unmanned Ground Vehicles (UGV’s) as well as Unmanned Air Vehicles (UAV’s). The activities will be discussed in the context of the science and technology construct used by the DOE Technology Roadmap for Robotics and Intelligent Machines (RIM)1 published in 1998; namely, Perception, Reasoning, Action, and Integration. The activities to be discussed span from research and development to deployment in field operations. The activities support customers in other agencies. The discussion of "perception" will include hyperspectral sensors, complex patterns discrimination, multisensor fusion and advances in LADAR technologies, including real-world perception. "Reasoning" activities to be covered include cooperative controls, distributed systems, ad-hoc networks, platform-centric intelligence, and adaptable communications. The paper will discuss "action" activities such as advanced mobility and various air and ground platforms. In the RIM construct, "integration" includes the Human-Machine Integration. Accordingly the paper will discuss adjustable autonomy and the collaboration of operator(s) with distributed UGV’s and UAV’s. Integration also refers to the applications of these technologies into systems to perform operations such as perimeter surveillance, large-area monitoring and reconnaissance. Unique facilities and test beds for advanced mobile systems will be described. Given that this paper is an overview, rather than delve into specific detail in these activities, other more exhaustive references and sources will be cited extensively.

  16. Multistage Electrophoretic Separators

    NASA Technical Reports Server (NTRS)

    Thomas, Nathan; Doyle, John F.; Kurk, Andy; Vellinger, John C.; Todd, Paul

    2006-01-01

    A multistage electrophoresis apparatus has been invented for use in the separation of cells, protein molecules, and other particles and solutes in concentrated aqueous solutions and suspensions. The design exploits free electrophoresis but overcomes the deficiencies of prior free-electrophoretic separators by incorporating a combination of published advances in mathematical modeling of convection, sedimentation, electro-osmotic flow, and the sedimentation and aggregation of droplets. In comparison with other electrophoretic separators, these apparatuses are easier to use and are better suited to separation in relatively large quantities characterized in the art as preparative (in contradistinction to smaller quantities characterized in the art as analytical). In a multistage electrophoretic separator according to the invention, an applied vertical steady electric field draws the electrically charged particles of interest from within a cuvette to within a collection cavity that has been moved into position of the cuvette. There are multiple collection cavities arranged in a circle; each is aligned with the cuvette for a prescribed short time. The multistage, short-migration-path character of the invention solves, possibly for the first time, the fluid-instability problems associated with free electrophoresis. The figure shows a prototype multistage electrophoretic separator that includes four sample stations and five collection stages per sample. At each sample station, an aqueous solution or suspension containing charged species to be separated is loaded into a cuvette, which is machined into a top plate. The apparatus includes a lower plate, into which 20 collection cavities have been milled. Each cavity is filled with an electrophoresis buffer solution. For the collection of an electrophoretic fraction, the lower plate is rotated to move a designated collection cavity into alignment with the opening of the cuvette. An electric field is then applied between a non

  17. Active microrheology in active matter systems: Mobility, intermittency, and avalanches.

    PubMed

    Reichhardt, C; Reichhardt, C J Olson

    2015-03-01

    We examine the mobility and velocity fluctuations of a driven particle moving through an active matter bath of self-mobile disks for varied density or area coverage and varied activity. We show that the driven particle mobility can exhibit nonmonotonic behavior that is correlated with distinct changes in the spatiotemporal structures that arise in the active media. We demonstrate that the probe particle velocity distributions exhibit specific features in the different dynamic regimes and identify an activity-induced uniform crystallization that occurs for moderate activity levels and is distinct from the previously observed higher activity cluster phase. The velocity distribution in the cluster phase has telegraph noise characteristics produced when the probe particle moves alternately through high-mobility areas that are in the gas state and low-mobility areas that are in the dense phase. For higher densities and large activities, the system enters what we characterize as an active jamming regime. Here the probe particle moves in intermittent jumps or avalanches that have power-law-distributed sizes that are similar to the avalanche distributions observed for nonactive disk systems near the jamming transition.

  18. Active microrheology in active matter systems: Mobility, intermittency, and avalanches.

    PubMed

    Reichhardt, C; Reichhardt, C J Olson

    2015-03-01

    We examine the mobility and velocity fluctuations of a driven particle moving through an active matter bath of self-mobile disks for varied density or area coverage and varied activity. We show that the driven particle mobility can exhibit nonmonotonic behavior that is correlated with distinct changes in the spatiotemporal structures that arise in the active media. We demonstrate that the probe particle velocity distributions exhibit specific features in the different dynamic regimes and identify an activity-induced uniform crystallization that occurs for moderate activity levels and is distinct from the previously observed higher activity cluster phase. The velocity distribution in the cluster phase has telegraph noise characteristics produced when the probe particle moves alternately through high-mobility areas that are in the gas state and low-mobility areas that are in the dense phase. For higher densities and large activities, the system enters what we characterize as an active jamming regime. Here the probe particle moves in intermittent jumps or avalanches that have power-law-distributed sizes that are similar to the avalanche distributions observed for nonactive disk systems near the jamming transition. PMID:25871116

  19. Active microrheology in active matter systems: Mobility, intermittency, and avalanches

    NASA Astrophysics Data System (ADS)

    Reichhardt, C.; Reichhardt, C. J. Olson

    2015-03-01

    We examine the mobility and velocity fluctuations of a driven particle moving through an active matter bath of self-mobile disks for varied density or area coverage and varied activity. We show that the driven particle mobility can exhibit nonmonotonic behavior that is correlated with distinct changes in the spatiotemporal structures that arise in the active media. We demonstrate that the probe particle velocity distributions exhibit specific features in the different dynamic regimes and identify an activity-induced uniform crystallization that occurs for moderate activity levels and is distinct from the previously observed higher activity cluster phase. The velocity distribution in the cluster phase has telegraph noise characteristics produced when the probe particle moves alternately through high-mobility areas that are in the gas state and low-mobility areas that are in the dense phase. For higher densities and large activities, the system enters what we characterize as an active jamming regime. Here the probe particle moves in intermittent jumps or avalanches that have power-law-distributed sizes that are similar to the avalanche distributions observed for nonactive disk systems near the jamming transition.

  20. Determination of the dissociation constants (pKa) of secondary and tertiary amines in organic media by capillary electrophoresis and their role in the electrophoretic mobility order inversion.

    PubMed

    Cantu, Marcelo Delmar; Hillebranda, Sandro; Carrilho, Emanuel

    2005-03-11

    Non-aqueous capillary electrophoresis (NACE) may provide a selectivity enhancement in separations since the analyte dissociation constants (pKa) in organic media are different from those in aqueous solutions. In this work, we have studied the inversion in mobility order observed in the separation of tertiary (imipramine (IMI) and amitryptiline (AMI)) and secondary amines (desipramine (DES) and nortryptiline (NOR)) in water, methanol, and acetonitrile. We have determined the pKa values in those solvents and the variation of dissociation constants with the temperature. From these data, and applying the Van't Hoff equation, we have calculated the thermodynamic parameters deltaH and deltaS. The pKa values found in methanol for DES, NOR, IMI, and AMI were 10.80, 10.79, 10.38, and 10.33, respectively. On the other hand, in acetonitrile an opposite relation was found since the values were 20.60, 20.67, 20.74, and 20.81 for DES, NOR, IMI, and AMI. This is the reason why a migration order inversion is observed in NACE for these solvents. The thermodynamic parameters were evaluated and presented a tendency that can be correlated with that observed for pKa values.

  1. Preparation of guinea pig macrophage for electrophoretic experiments in space

    NASA Technical Reports Server (NTRS)

    1979-01-01

    Methods of storage and cultivation of macrophage cells in preparation for space experiments were investigated. Results show that freezing and thawing immediately after extraction did not cause any change in viability or electrophoretic mobility of the cells. A prolonged storage at -80 C did cause cell damage as indicated by a 95% reduction in variable cells. Cell damage was decreased when Glycerol or Dimethyl Sulfoxide (DMSO) was added as a cryogenic protective agent. A 100% viability was observed in cultivation experiments after two weeks due to the additional serum. Results from gamma-glutamyl transpeptidase study showed a zero activity rate. It is suggested that a flat stationary field be used for the collection and use of macrophage. It was found that a 24-hour delay in obtaining macrophage cells helps to maintain a pure culture.

  2. Analysis of the interfacial properties of fibrillated and nonfibrillated oral streptococcal strains from electrophoretic mobility and titration measurements: evidence for the shortcomings of the 'classical soft-particle approach'.

    PubMed

    Duval, Jérôme F L; Busscher, Henk J; van de Belt-Gritter, Betsy; van der Mei, Henny C; Norde, Willem

    2005-11-22

    Chemical and structural intricacies of bacterial cells complicate the quantitative evaluation of the physicochemical properties pertaining to the cell surface. The presence of various types of cell surface appendages has a large impact on those properties and therefore on various interfacial phenomena, such as aggregation and adhesion. In this paper, an advanced analysis of the electrophoretic mobilities of fibrillated and nonfibrillated strains (Streptococcus salivarius HB and Streptococcus salivarius HB-C12, respectively) is performed over a wide range of pH and ionic strength conditions on the basis of a recent electrokinetic theory for soft particles. The latter extends the approximate formalism originally developed by Ohshima by solving rigorously the fundamental electrokinetic equations without restrictions on the bacterial size, charge, and double layer thickness. It further allows (i) a straightforward implementation of the dissociation characteristics, as evaluated from titration experiments, of the ionogenic charged groups distributed throughout the bacterial cell wall and/or the surrounding exopolymer layer and (ii) the inclusion of possible specific interactions between the charged groups and ions from the background electrolyte other than charge-determining ions. The theory also enables an estimation of possible swelling/shrinking processes operating on the outer polymeric layer of the bacterium. Application of the electrokinetic model to HB and HB-C12 clearly shows a significant discrepancy between the amount of surface charges probed by electrophoresis and by protolytic titration. This is ascribed to the specific adsorption of cations onto pristine charged sites in the cell wall. Physicochemical parameters pertaining to the hydrodynamics (softness degree) and electrostatics of the bacterial cell wall (HB-C12) and soft polymeric layer (HB) are quantitatively derived.

  3. Electrophoretic deposition of biomaterials.

    PubMed

    Boccaccini, A R; Keim, S; Ma, R; Li, Y; Zhitomirsky, I

    2010-10-01

    Electrophoretic deposition (EPD) is attracting increasing attention as an effective technique for the processing of biomaterials, specifically bioactive coatings and biomedical nanostructures. The well-known advantages of EPD for the production of a wide range of microstructures and nanostructures as well as unique and complex material combinations are being exploited, starting from well-dispersed suspensions of biomaterials in particulate form (microsized and nanoscale particles, nanotubes, nanoplatelets). EPD of biological entities such as enzymes, bacteria and cells is also being investigated. The review presents a comprehensive summary and discussion of relevant recent work on EPD describing the specific application of the technique in the processing of several biomaterials, focusing on (i) conventional bioactive (inorganic) coatings, e.g. hydroxyapatite or bioactive glass coatings on orthopaedic implants, and (ii) biomedical nanostructures, including biopolymer-ceramic nanocomposites, carbon nanotube coatings, tissue engineering scaffolds, deposition of proteins and other biological entities for sensors and advanced functional coatings. It is the intention to inform the reader on how EPD has become an important tool in advanced biomaterials processing, as a convenient alternative to conventional methods, and to present the potential of the technique to manipulate and control the deposition of a range of nanomaterials of interest in the biomedical and biotechnology fields.

  4. Electrophoretic deposition of biomaterials

    PubMed Central

    Boccaccini, A. R.; Keim, S.; Ma, R.; Li, Y.; Zhitomirsky, I.

    2010-01-01

    Electrophoretic deposition (EPD) is attracting increasing attention as an effective technique for the processing of biomaterials, specifically bioactive coatings and biomedical nanostructures. The well-known advantages of EPD for the production of a wide range of microstructures and nanostructures as well as unique and complex material combinations are being exploited, starting from well-dispersed suspensions of biomaterials in particulate form (microsized and nanoscale particles, nanotubes, nanoplatelets). EPD of biological entities such as enzymes, bacteria and cells is also being investigated. The review presents a comprehensive summary and discussion of relevant recent work on EPD describing the specific application of the technique in the processing of several biomaterials, focusing on (i) conventional bioactive (inorganic) coatings, e.g. hydroxyapatite or bioactive glass coatings on orthopaedic implants, and (ii) biomedical nanostructures, including biopolymer–ceramic nanocomposites, carbon nanotube coatings, tissue engineering scaffolds, deposition of proteins and other biological entities for sensors and advanced functional coatings. It is the intention to inform the reader on how EPD has become an important tool in advanced biomaterials processing, as a convenient alternative to conventional methods, and to present the potential of the technique to manipulate and control the deposition of a range of nanomaterials of interest in the biomedical and biotechnology fields. PMID:20504802

  5. INFLUENCE OF BORATE BUFFERS ON THE ELECTROPHORETIC BEHAVIOR OF HUMIC SUBSTANCES IN CAPILLARY ZONE ELECTROPHORESIS

    EPA Science Inventory

    The influence of tetrahydroxyborate ions on the electrophoretic mobility of humic acids was evaluated by capillary electrophoresis (CE). Depending on the molarity of borate ions in the separation buffer, the humic acids exhibit electropherograms with sharp peaks consistently exte...

  6. Draft Genome Sequences of Eight Nontypeable Haemophilus influenzae Strains Previously Characterized Using an Electrophoretic Typing Scheme

    PubMed Central

    Mussa, Huda J.; VanWagoner, Timothy M.; Seale, Thomas W.; Whitby, Paul W.; Stull, Terrence L.

    2015-01-01

    Nontypeable Haemophilus influenzae is an important cause of human disease. Strains were selected for genome sequencing to represent the breadth of nontypeable strains within the species, as previously defined by the electrophoretic mobility of 16 metabolic enzymes. PMID:26607889

  7. Development of the Resolution Theory for Electrophoretic Exclusion

    PubMed Central

    Kenyon, Stacy M.; Keebaugh, Michael W.; Hayes, Mark A.

    2015-01-01

    Electrophoretic exclusion, a technique that differentiates species in bulk solution near a channel entrance, has been demonstrated on benchtop and microdevice designs. In these systems, separation occurs when the electrophoretic velocity of one species is greater than the opposing hydrodynamic flow, while the velocity of the other species is less than that flow. Although exclusion has been demonstrated in multiple systems for a range of analytes, a theoretical assessment of resolution has not been addressed. To compare the results of these calculations to traditional techniques, the performance is expressed in terms of smallest difference in electrophoretic mobilities that can be completely separated (R = 1.5). The calculations indicate that closest resolvable species (Δμmin) differ by approximately 10−13 m2/Vs and peak capacity (nc) is 1000. Published experimental data is compared to these calculated results. PMID:24916305

  8. a Multidisciplinary Analytical Framework for Studying Active Mobility Patterns

    NASA Astrophysics Data System (ADS)

    Orellana, D.; Hermida, C.; Osorio, P.

    2016-06-01

    Intermediate cities are urged to change and adapt their mobility systems from a high energy-demanding motorized model to a sustainable low-motorized model. In order to accomplish such a model, city administrations need to better understand active mobility patterns and their links to socio-demographic and cultural aspects of the population. During the last decade, researchers have demonstrated the potential of geo-location technologies and mobile devices to gather massive amounts of data for mobility studies. However, the analysis and interpretation of this data has been carried out by specialized research groups with relatively narrow approaches from different disciplines. Consequently, broader questions remain less explored, mainly those relating to spatial behaviour of individuals and populations with their geographic environment and the motivations and perceptions shaping such behaviour. Understanding sustainable mobility and exploring new research paths require an interdisciplinary approach given the complex nature of mobility systems and their social, economic and environmental impacts. Here, we introduce the elements for a multidisciplinary analytical framework for studying active mobility patterns comprised of three components: a) Methodological, b) Behavioural, and c) Perceptual. We demonstrate the applicability of the framework by analysing mobility patterns of cyclists and pedestrians in an intermediate city integrating a range of techniques, including: GPS tracking, spatial analysis, auto-ethnography, and perceptual mapping. The results demonstrated the existence of non-evident spatial behaviours and how perceptual features affect mobility. This knowledge is useful for developing policies and practices for sustainable mobility planning.

  9. Synthesis, characterization, and photocatalytic activities of Cobalt(II)-Titanium dioxide nanorods, and electrophoretic deposition of Titanium dioxide nanoparticle/nanorod composite films for self-cleaning applications

    NASA Astrophysics Data System (ADS)

    Kang, Wonjun

    This dissertation consists of two projects. The first project is synthesis, characterization, and photocatalytic activities of Co(II)-TiO2 nanorods. We modified brookite TiO2 nanorods with cobalt(II) ions to design new photocatalysts with visible light absorption. X-ray absorption spectroscopy (XAS) and X-ray photoelectron spectroscopy (XPS) data indicated that the local structure of Co(II)-TiO2 nanorods was shown as tetrahedral and octahedral Co(II) sites at TiO2 nanorod surface. Dimethylglyoxime (DMG) has been used to remove surface Co(II) from Co(II)-TiO2 nanorods to determine single-site Co(II) ions selectively attached to the TiO 2 nanorod surface. We proposed a mechanism that the Co-Co bond of the precursor Co2(CO)8 undergoes heterolysis followed by disproportionation of Co(I) to produce Co(II) and Co(0) precipitate. Finally, the Co(II)-TiO2 nanorods showed greater activity than TiO 2 nanorods in the degradation of 5,8-dihydroxy-1,4-naphthoquinone (DHNQ) dye under visible light irradiation. The second project is electrophoretic deposition (EPD) of TiO2 nanoparticle/nanorod composite films for self-cleaning applications. We developed novel electrolyte system for EPD of TiO2 nanoparticle/nanorod composites for self-cleaning coatings. A mixture of TiO2 powder and TiO2 nanorods was used as EPD suspension in a mixture of THF and acetone. TiO2 nanoparticle/nanorod composite films were fabricated on aluminium substrates via the EPD method, and were characterized by scanning electron microscope (SEM). SEM images showed that TiO2 nanoparticle/nanorod composite films had a uniform pore structure. The hydrophobic properties of surfaces in TiO2 nanoparticle/nanorod composite films were evaluated by water contact angle measurements. It was found that the surfaces of TiO2 nanoparticle/nanorod composite films were hydrophobic with contact angle of 103°. These hydrophobic surfaces are expected to have potential applications for self-cleaning.

  10. Electrophoretic Process For Purifying Wastewater

    NASA Technical Reports Server (NTRS)

    Sammons, David W.; Twitty, Garland E.; Sharnez, Rizwan; Egen, Ned B.

    1992-01-01

    Microbes, poisonous substances, and colloidal particles removed by combination of electric fields. Electrophoretic process removes pathogenicorganisms, toxins, toxic metals, and cooloidal soil particles from wastewater. Used to render domestic, industrial, and agricultural wastewater streams potable. Process also useful in bioregenerative and other closed systems like in space stations and submarines, where water must be recycled.

  11. Electrophoretically unique amylases in rat livers: phylogenic and ontogenic study on the mammalian liver.

    PubMed

    Koyama, Iwao; Komine, Shin-Ichi; Hokari, Shigeru; Matsunaga, Toshiyuki; Nakamura, Koh-Ich; Komoda, Tsugikazu

    2002-09-01

    Liver amylase activity in rodents was assayed with Blue Starch as substrate, and found to be higher than in humans or pigs. Based on the result of concanavalin A affinity chromatography, we found that the sugar moieties of amylase molecules increased in parallel with amylase activity in the tested mammals. However, the amounts of amylase proteins determined by Western bloting with anti-human salivary-type antibody as the probe, were similar to the levels in mammalian livers. Moreover, a similar expression of amylase mRNA was also detected in the mammalian livers by a reverse transcriptional-polymerase chain reaction using primers specific for the human salivary and/or pancreatic amylase complementary DNA (cDNA) sequences. The amylase was detected at the catalytic activity, protein molecule and mRNA levels in rat liver at all ages from fetus to adult. Salivary-type liver amylase activity increased up to one week after birth, and was maintained at the adult level thereafter. However, based on the results of the electrophoretic mobility test, livers with accelerated amylase activity, e.g., at 2-4 weeks after birth or during liver regeneration after partial hepatectomy, were also found to express an amylase electrophoretical identical to pancreatic-type amylase in addition to salivary-type activity. These results suggest that the liver may express an etopic amylase in a certain condition.

  12. An Electrophoretic Analysis of the Isozymes of Malate Dehydrogenase in Several Different Plants 1

    PubMed Central

    Weimberg, Ralph

    1968-01-01

    The particulate and soluble fractions of cell-free extracts from seeds, roots, and leaves of 10 different plants were examined electrophoretically for isozymes of malate dehydrogenase. Distinct isozyme patterns were observed for each plant and even for the individual tissues of each species. There were some isozymes in several different plant extracts with equal electrophoretic mobilities, but there was no isozyme band that was common to all tissues or to all plants. Images PMID:16656816

  13. Identification and quantitation of morphological cell types in electrophoretically separated human embryonic kidney cell cultures

    NASA Technical Reports Server (NTRS)

    Williams, K. B.; Kunze, M. E.; Todd, P. W.

    1985-01-01

    Four major cell types were identified by phase microscopy in early passage human embryonic kidney cell cultures. They are small and large epithelioid, domed, and fenestrated cells. Fibroblasts are also present in some explants. The percent of each cell type changes with passage number as any given culture grows. As a general rule, the fraction of small epithelioid cells increases, while the fraction of fenestrated cells, always small, decreases further. When fibroblasts are present, they always increase in percentage of the total cell population. Electrophoretic separation of early passage cells showed that the domed cells have the highest electrophoretic mobility, fibroblasts have an intermediate high mobility, small epithelioid cells have a low mobility, broadly distributed, and fenestrated cells have the lowest mobility. All cell types were broadly distributed among electrophoretic subfractions, which were never pure but only enriched with respect to a given cell type.

  14. Sensitive and robust electrophoretic NMR: Instrumentation and experiments

    NASA Astrophysics Data System (ADS)

    Hallberg, Fredrik; Furó, István; Yushmanov, Pavel V.; Stilbs, Peter

    2008-05-01

    Although simple as a concept, electrophoretic NMR (eNMR) has so far failed to find wider application. Problems encountered are mainly due to disturbing and partly irreproducible convection-like bulk flow effects from both electro-osmosis and thermal convection. Additionally, bubble formation at the electrodes and rf noise pickup has constrained the typical sample geometry to U-tube-like arrangements with a small filling factor and a low resulting NMR sensitivity. Furthermore, the sign of the electrophoretic mobility cancels out in U-tube geometries. We present here a new electrophoretic sample cell based on a vertically placed conventional NMR sample tube with bubble-suppressing palladium metal as electrode material. A suitable radiofrequency filter design prevents noise pickup by the NMR sample coil from the high-voltage leads which extend into the sensitive sample volume. Hence, the obtained signal-to-noise ratio of this cell is one order of magnitude higher than that of our previous U-tube cells. Permitted by the retention of the sign of the displacement-related signal phase in the new cell design, an experimental approach is described where bulk flow effects by electro-osmosis and/or thermal convection are compensated through parallel monitoring of a reference signal from a non-charged species in the sample. This approach, together with a CPMG-like pulse train scheme provides a superior first-order cancellation of non-electrophoretic bulk flow effects.

  15. Electrophoretic study of Clostridium species.

    PubMed Central

    Cato, E P; Hash, D E; Holdeman, L V; Moore, W E

    1982-01-01

    Polyacrylamide gel electrophoretic analysis of soluble cellular proteins (without sodium dodecyl sulfate) of 70 Clostridium species indicated that the procedure was readily applicable to the differentiation of species in the genus. The protein patterns correlated well with the available DNA homology data and with most accepted differential tests. Results indicated that several earlier names for species were synonyms of those of accepted species and that two accepted species may be synonymous. Images PMID:6175658

  16. Design Modification of Electrophoretic Equipment

    NASA Technical Reports Server (NTRS)

    Reddick, J. M.; Hirsch, I.

    1973-01-01

    The improved design of a zone electrophoretic sampler is reported that can be used in mass screening for hemoglobin S, the cause of sickle cell anemia. Considered is a high voltage multicell cellulose acetate device that requires 5 to 6 minutes electrophoresis periods; cells may be activitated individually or simultaneously. A multisample hemoglobin applicator standardizes the amount of sample applied and transfers the homolysate to the electrical wires.

  17. Supporting Mobile Collaborative Activities through Scaffolded Flexible Grouping

    ERIC Educational Resources Information Center

    Boticki, Ivica; Looi, Chee-Kit; Wong, Lung-Hsiang

    2011-01-01

    Within the field of Mobile Computer-Supported Collaborative Learning (mCSCL), we are interested in exploring the space of collaborative activities that enable students to practice communication, negotiation and decision-making skills. Collaboration is via learning activities that circumvent the constraints of fixed seating or locations of…

  18. Recent patents on electrophoretic displays and materials.

    PubMed

    Christophersen, Marc; Phlips, Bernard F

    2010-11-01

    Electrophoretic displays (EPDs) have made their way into consumer products. EPDs enable displays that offer the look and form of a printed page, often called "electronic paper". We will review recent apparatus and method patents for EPD devices and their fabrication. A brief introduction into the basic display operation and history of EPDs is given, while pointing out the technological challenges and difficulties for inventors. Recently, the majority of scientific publications and patenting activity has been directed to micro-segmented EPDs. These devices exhibit high optical reflectance and contrast, wide viewing angle, and high image resolution. Micro-segmented EPDs can also be integrated with flexible transistors technologies into flexible displays. Typical particles size ranges from 200 nm to 2 micrometer. Currently one very active area of patenting is the development of full-color EPDs. We summarize the recent patenting activity for EPDs and provide comments on perceiving factors driving intellectual property protection for EPD technologies. PMID:20565384

  19. Reversed-polarity capillary zone electrophoretic analysis of usnic acid.

    PubMed

    Kreft, S; Strukelj, B

    2001-08-01

    A capillary zone electrophoretic (CZE) method for the determination of usnic acid is described for the first time. Usnic acid is an antibiotic substance from lichens. Due to its low solubility in water, a high content of methanol in CZE buffer is required. Because of the methanol in the buffer, the electroosmotic flow velocity was lower than the electrophoretic mobility of usnic acid. Accordingly, the use of reversed-polarity (with the anode on the detector side of the capillary) was necessary. The optimal buffer composition was 50 mM NaOH, 20 mM acetic acid and 5% water in methanol. The detection limit of UV detector at 290 nm for usnic acid in the injected extract was 3.5 mg/L and the relative standard deviation of the normalized peak area was 3.3% at 250 mg/L.

  20. Demonstration of cell-ricin interaction by electrophoretic light scattering.

    PubMed

    Hakim Hachemi, B; Betrencourt, C; Volochine, B; Frénoy, J P; Chraïbi, Z; Alfsen, A; Lavialle, F

    1989-07-01

    Electrophoretic light scattering has been used to investigate the interaction of ricin, a vegetal toxin, with cells. This technique allowed measurements in the presence of free ligand and proved particularly useful for the study of a system with low affinity. The electrophoretic mobility of erythrocytes and oligodendrocytes was found equal to 2.08 x 10(-8) and 2.35 x 10(-8)m2s-1V-1, respectively. Upon ricin binding, these values decreased significantly. This change was related to the saturation of the binding sites. The specificity of the interaction was demonstrated by conducting the experiments in the presence of lactose. This specific inhibitor fully prevented the ricin-cell interaction.

  1. Electrophoretic analysis of multiple forms of myosin in fast-twitch and slow-twitch muscles of the chick.

    PubMed Central

    Hoh, J Y; McGrath, P A; White, R I

    1976-01-01

    1. A method is described for the electrophoretic analysis of intact myosin in polyacrylamide gel in a buffer system containing 0.02 M-pyrophosphate and 10% (v/v) glycerol, pH 8.8. 2. In this system chicken skeletal-muscle myosins reveal five distinct electrophoretic components, three components from the fast-twitch posterior latissimus dorsi muscle and two slower-migrating components from the slow-twitch anterior latissimus dorsi muscle. 3. The Ca2+-activated ATPase (adenosine triphosphatase) activity of myosin components was measured by densitometric scanning of the gel for the Ca3(PO4)2 precipitate formed during the ATPase reaction and subsequently for stained protein. Each component from the same muscle appears to have identical ATPase activity, but components from the fast-twitch muscle had an activity 2.2 times higher than those from the slow-twitch muscle. 4. On re-electrophoresis in the same buffer system, individual fractions of fast-twitch myosin did not reproduce the three-band pattern of the original myosin, but migrated at rates consistent with their original mobility. 5. Analysis of the mobility of the three fast-twitch myosin components in gels of different concentrations suggests that they are not stable oligomers of each other. 6. It is suggested that these components of fast-twitch myosin and slow-twitch myosin are isoenzymes of myosin. PMID:183747

  2. GalileoMobile: Interactive astronomy activities in schools

    NASA Astrophysics Data System (ADS)

    Vasquez, M.; Dasi Espuig, M.

    2014-04-01

    GalileoMobile is an itinerant science education initiative run on a voluntary basis by an international team of astronomers, educators, and science communicators. Our team's main goal is to make astronomy accessible to schools and communities around the globe that have little or no access to outreach actions. We do this by performing teacher workshops, activities with students, and donating educational material. Since the creation of GalileoMobile in 2008, we have travelled to Chile, Bolivia, Peru, India, and Uganda, and worked with 56 schools in total.

  3. A survey of online activity recognition using mobile phones.

    PubMed

    Shoaib, Muhammad; Bosch, Stephan; Incel, Ozlem Durmaz; Scholten, Hans; Havinga, Paul J M

    2015-01-19

    Physical activity recognition using embedded sensors has enabled many context-aware applications in different areas, such as healthcare. Initially, one or more dedicated wearable sensors were used for such applications. However, recently, many researchers started using mobile phones for this purpose, since these ubiquitous devices are equipped with various sensors, ranging from accelerometers to magnetic field sensors. In most of the current studies, sensor data collected for activity recognition are analyzed offline using machine learning tools. However, there is now a trend towards implementing activity recognition systems on these devices in an online manner, since modern mobile phones have become more powerful in terms of available resources, such as CPU, memory and battery. The research on offline activity recognition has been reviewed in several earlier studies in detail. However, work done on online activity recognition is still in its infancy and is yet to be reviewed. In this paper, we review the studies done so far that implement activity recognition systems on mobile phones and use only their on-board sensors. We discuss various aspects of these studies. Moreover, we discuss their limitations and present various recommendations for future research.

  4. A Survey of Online Activity Recognition Using Mobile Phones

    PubMed Central

    Shoaib, Muhammad; Bosch, Stephan; Incel, Ozlem Durmaz; Scholten, Hans; Havinga, Paul J.M.

    2015-01-01

    Physical activity recognition using embedded sensors has enabled many context-aware applications in different areas, such as healthcare. Initially, one or more dedicated wearable sensors were used for such applications. However, recently, many researchers started using mobile phones for this purpose, since these ubiquitous devices are equipped with various sensors, ranging from accelerometers to magnetic field sensors. In most of the current studies, sensor data collected for activity recognition are analyzed offline using machine learning tools. However, there is now a trend towards implementing activity recognition systems on these devices in an online manner, since modern mobile phones have become more powerful in terms of available resources, such as CPU, memory and battery. The research on offline activity recognition has been reviewed in several earlier studies in detail. However, work done on online activity recognition is still in its infancy and is yet to be reviewed. In this paper, we review the studies done so far that implement activity recognition systems on mobile phones and use only their on-board sensors. We discuss various aspects of these studies. Moreover, we discuss their limitations and present various recommendations for future research. PMID:25608213

  5. Electrophoretic separator for purifying biologicals, part 1

    NASA Technical Reports Server (NTRS)

    Mccreight, L. R.

    1978-01-01

    A program to develop an engineering model of an electrophoretic separator for purifying biologicals is summarized. An extensive mathematical modeling study and numerous ground based tests were included. Focus was placed on developing an actual electrophoretic separator of the continuous flow type, configured and suitable for flight testing as a space processing applications rocket payload.

  6. Electrophoretic karyotype of Cercospora kikuchii.

    PubMed

    Hightower, R C; Callahan, T M; Upchurch, R G

    1995-02-01

    Classical genetic analyses are not possible with the phytopathogenic fungus Cercospora kikuchii since no sexual stage has been identified. To facilitate gene mapping and to develop an understanding of the genome organization of C. kikuchii, an electrophoretic karyotype has been obtained using contour-clamped homogeneous electric field gel electrophoresis (CHEF). Eight chromosomes, two of which migrate as a doublet, have been separated into seven bands ranging from 2.0 to 5.5 Mb. Using this determination of chromosome number and size, the total genome size of C. kikuchii is estimated to be 28.4 Mb. In addition, genes encoding tubulin, ribosomal DNA, and four previously isolated light-enhanced cDNAs from C. kikuchii were assigned to chromosomes by Southern-hybridization analysis of CHEF blots.

  7. An electrophoretic characterization of serum proteins of the collared peccary (Tayassu tajacu).

    PubMed

    Lochmiller, R L; Hellgren, E C; Varner, L W; Grant, W E

    1984-01-01

    Serum proteins of the collared peccary (Tayassu tajacu) were analyzed by agarose gel electrophoresis for wild adult males and females, nursing young, and reproductively-active females in captivity. Electrophoretic profiles of the adult peccary showed at least six distinct protein bands corresponding to the fractions: albumin, alpha-1, alpha-2, beta-1, beta-2, and gamma globulin. Globulin fractions of the peccary had different mobilities from the domestic swine. The only sexual dimorphisms were associated with the beta globulin:albumin ratio and the albumin:globulin ratio. Ingestion of colostrum in 1-day-old neonates was marked by a very large increase in gamma globulins. The only significant difference between pregnant and lactating females was in the alpha globulin:beta globulin ratio. Lactating females had higher concentrations of alpha-2 globulin than non-pregnant females.

  8. Electrophoretic separation of kidney and pituitary cells on STS-8

    NASA Technical Reports Server (NTRS)

    Morrison, D. R.; Nachtwey, D. S.; Barlow, G. H.; Cleveland, C.; Lanham, J. W.; Farrington, M. A.; Hatfield, J. M.; Hymer, W. C.; Grindeland, R.; Lewis, M. L.

    1984-01-01

    Specific secretory cells were separated from suspensions of cultured primary human embryonic cells and rat pituitary cells in microgravity conditions, with an objective of isolating the subfractions of kidney cells that produce the largest amount of urakinase, and the subfractions of rat pituitary cells that secrete growth hormones (GH), prolactin (PRL), and other hormones. It is inferred from the experimental observations that the surface charge distributions of the GH-containing cells differ from those of the PRL-containing cells, which is explained by the presence of secretory products on the surface of pituitary cells. For kidney cells, the electrophoretic mobility distributions in flight experiments were spread more than the ground controls.

  9. Inferring Human Activity in Mobile Devices by Computing Multiple Contexts

    PubMed Central

    Chen, Ruizhi; Chu, Tianxing; Liu, Keqiang; Liu, Jingbin; Chen, Yuwei

    2015-01-01

    This paper introduces a framework for inferring human activities in mobile devices by computing spatial contexts, temporal contexts, spatiotemporal contexts, and user contexts. A spatial context is a significant location that is defined as a geofence, which can be a node associated with a circle, or a polygon; a temporal context contains time-related information that can be e.g., a local time tag, a time difference between geographical locations, or a timespan; a spatiotemporal context is defined as a dwelling length at a particular spatial context; and a user context includes user-related information that can be the user’s mobility contexts, environmental contexts, psychological contexts or social contexts. Using the measurements of the built-in sensors and radio signals in mobile devices, we can snapshot a contextual tuple for every second including aforementioned contexts. Giving a contextual tuple, the framework evaluates the posteriori probability of each candidate activity in real-time using a Naïve Bayes classifier. A large dataset containing 710,436 contextual tuples has been recorded for one week from an experiment carried out at Texas A&M University Corpus Christi with three participants. The test results demonstrate that the multi-context solution significantly outperforms the spatial-context-only solution. A classification accuracy of 61.7% is achieved for the spatial-context-only solution, while 88.8% is achieved for the multi-context solution. PMID:26343665

  10. Electrophoretic control of actomyosin motility

    NASA Astrophysics Data System (ADS)

    Hanson, Kristi L.; Solana, Gerardin; Nicolau, Dan V.

    2005-03-01

    The effect of DC electric field strength on in vitro actomyosin motility was examined. Rabbit skeletal muscle heavy meromyosin (HMM) was adsorbed to nitrocellulose-coated glass, and the myosin driven movement of fluorescently labeled actin filaments was recorded in the presence of 0 to 9000 V m-1 applied DC voltage. The applied electric field resulted in increased filament velocity and oriented actin movement, with leading heads of filaments directed towards the positive electrode. Velocity (v) was found to increase moderately with electric field strength at applied fields up to ~ 4500 V m-1 (Δv/ΔE = 0.037 μm2 V-1sec-1), and then increased at a more rapid rate (Δv/ΔE = 0.100 μm2 V-1sec-1) at higher field strengths up to 9000 V m-1. The electrophoretic effect caused up to 70% of actin motion to be oriented within 30 degrees of the positive electrode, with the largest effect observed using an applied field of 6000 V m-1. Higher electric field strengths caused filament breakage.

  11. Automated Parallel Capillary Electrophoretic System

    DOEpatents

    Li, Qingbo; Kane, Thomas E.; Liu, Changsheng; Sonnenschein, Bernard; Sharer, Michael V.; Kernan, John R.

    2000-02-22

    An automated electrophoretic system is disclosed. The system employs a capillary cartridge having a plurality of capillary tubes. The cartridge has a first array of capillary ends projecting from one side of a plate. The first array of capillary ends are spaced apart in substantially the same manner as the wells of a microtitre tray of standard size. This allows one to simultaneously perform capillary electrophoresis on samples present in each of the wells of the tray. The system includes a stacked, dual carousel arrangement to eliminate cross-contamination resulting from reuse of the same buffer tray on consecutive executions from electrophoresis. The system also has a gel delivery module containing a gel syringe/a stepper motor or a high pressure chamber with a pump to quickly and uniformly deliver gel through the capillary tubes. The system further includes a multi-wavelength beam generator to generate a laser beam which produces a beam with a wide range of wavelengths. An off-line capillary reconditioner thoroughly cleans a capillary cartridge to enable simultaneous execution of electrophoresis with another capillary cartridge. The streamlined nature of the off-line capillary reconditioner offers the advantage of increased system throughput with a minimal increase in system cost.

  12. Different conformations of ribosomal DNA in active and inactive chromatin in Xenopus laevis.

    PubMed

    Spadafora, C; Riccardi, P

    1985-12-20

    The chromatin structure of the ribosomal DNA in Xenopus laevis was studied by micrococcal nuclease digestions of blood, liver and embryonic cell nuclei. We have found that BglI-restricted DNA from micrococcal nuclease-digested blood cell nuclei has an increased electrophoretic mobility compared to the undigested control. Micrococcal nuclease digestion of liver cell nuclei causes a very slight shift in mobility, only in the region of the spacer containing the "Bam Islands". In contrast, the mobility of ribosomal DNA in chromatin of embryonic cells, under identical digestion conditions, remains unaffected by the nuclease activity. Denaturing gels or ligase action on the nuclease-treated DNA abolishes the differences in the electrophoretic mobility. Ionic strength and ethidium bromide influence the relative electrophoretic migration of the two DNA fragment populations, suggesting that secondary structure may play an important role in the observed phenomena. In addition, restriction analysis under native electrophoretic conditions of DNA prepared from blood, liver and embryonic cells shows that blood cell DNA restriction fragments always have a faster mobility than the corresponding fragments of liver and embryo cell DNA. We therefore propose that nicking activity by micrococcal nuclease modifies the electrophoretic mobility of an unusual DNA conformation, present in blood cell, and to a lesser extent, in liver cell ribosomal chromatin. A possible function for these structures is discussed. The differences of the ribosomal chromatin structures in adult and embryonic tissues may reflect the potential of the genes to be expressed.

  13. CAPILLARY ELECTROPHORETIC BEHAVIOR OF SEVEN SULFONYLUREAS

    EPA Science Inventory

    The electrophoretic behavior of bensulfuron Me, sulfometuron Me, nicosulfuron (Accent), chlorimuron Et, thifensulfuron Me (Harmony), metsulfuron Me, and chlorsulfuron was studied under capillary zone electrophoresis (CZE) and micellar electrokinetic chromatography (MEKC) conditio...

  14. Electrophoretic Measurements of Lipid Charges in Supported Bilayers

    PubMed Central

    Poyton, Matthew F.; Cremer, Paul S.

    2013-01-01

    While electrophoresis in lipid bilayers has been performed since the 1970’s, the technique has until now been unable to accurately measure the charge on lipids and proteins within the membrane based on drift velocity measurements. Part of the problem is caused by the use of the Einstein-Smoluchowski equation to estimate the electrophoretic mobility of such species. The source of the error arises from the fact that a lipid head group is typically smaller than the Debye length of the adjacent aqueous solution in most electrophoresis experiments. Instead, the Henry equation can more accurately predict the electrophoretic mobility at sufficient ionic strength. This was done for three dye-labeled lipids with different sized head groups and a charge on each lipid of −1. Also, the charge was measured as a function of pH for two titratable lipids that were fluorescently labeled. Finally, it was shown that the Henry equation also has difficulties measuring the correct lipid charge at salt concentrations below 5 mM, where electroosmotic forces are more significant. PMID:24191728

  15. Active control of excessive sound emission on a mobile device.

    PubMed

    Jeon, Se-Woon; Youn, Dae Hee; Park, Young-cheol; Lee, Gun-Woo

    2015-04-01

    During a phone conversation, loud vocal emission from the far-end to the near-end space can disturb nearby people. In this paper, the possibility of actively controlling such unwanted sound emission using a control source placed on the mobile device is investigated. Two different approaches are tested: Global control, minimizing the potential energy measured along a volumetric space surface, and local control, minimizing the squared sound pressure at a discrete point on the phone. From the test results, both approaches can reduce the unwanted sound emission by more than 6 dB in the frequency range up to 2 kHz. PMID:25920885

  16. Multi-carrier mobile TDMA system with active array antenna

    NASA Technical Reports Server (NTRS)

    Suzuki, Ryutaro; Matsumoto, Yasushi; Hamamoto, Naokazu

    1990-01-01

    A multi-carrier time division multiple access (TDMA) is proposed for the future mobile satellite communications systems that include a multi-satellite system. This TDMA system employs the active array antenna in which the digital beam forming technique is adopted to control the antenna beam direction. The antenna beam forming is carried out at the base band frequency by using the digital signal processing technique. The time division duplex technique is applied for the TDM/TDMA burst format, in order not to overlap transmit and receive timing.

  17. Active control of excessive sound emission on a mobile device.

    PubMed

    Jeon, Se-Woon; Youn, Dae Hee; Park, Young-cheol; Lee, Gun-Woo

    2015-04-01

    During a phone conversation, loud vocal emission from the far-end to the near-end space can disturb nearby people. In this paper, the possibility of actively controlling such unwanted sound emission using a control source placed on the mobile device is investigated. Two different approaches are tested: Global control, minimizing the potential energy measured along a volumetric space surface, and local control, minimizing the squared sound pressure at a discrete point on the phone. From the test results, both approaches can reduce the unwanted sound emission by more than 6 dB in the frequency range up to 2 kHz.

  18. Dielectrophoretic and electrophoretic force analysis of colloidal fullerenes in a nematic liquid-crystal medium.

    PubMed

    Srivastava, Anoop Kumar; Kim, Miyoung; Kim, Sung Min; Kim, Mi-Kyung; Lee, Kyu; Lee, Young Hee; Lee, Myong-Hoon; Lee, Seung Hee

    2009-11-01

    This research focuses on the electrokinetic motion of fullerenes suspended in liquid crystal host medium, which are investigated in the homogeneously aligned nematic liquid crystal cells driven by in-plane field. We investigated the effect of electrophoretic and dielectrophoretic forces and related parameters of the colloidal fullerenes in liquid crystals. The electrophoretic mobility, zeta potential, and critical voltage have been evaluated. Fullerenes suspended in liquid crystal medium migrated toward the positive electrode, but were pulled back in the opposite direction when the polarity was reversed especially at low frequency range (<5 Hz) . At higher electric field and higher frequency ranges, the net displacement of fullerenes has been observed. We demonstrate that the dielectrophoretic force dominated the motion in the colloidal fullerenes by a proper analysis of different electrophoretic parameters. In addition, the electrodynamics of fullerenes was explained by applying the theory of the dielectrophoresis and Schwarz's formula. We propose a model to estimate the density of fullerenes suspended in liquid crystal medium.

  19. Does small-bodied salmon spawning activity enhance streambed mobility?

    NASA Astrophysics Data System (ADS)

    Hassan, Marwan A.; Tonina, Daniele; Buxton, Todd H.

    2015-09-01

    Female salmonids bury and lay their eggs in streambeds by digging a pit, which is then covered with sediment from a second pit that is dug immediately upstream. The spawning process alters streambed topography, winnows fine sediment, and mixes sediment in the active layer. The resulting egg nests (redds) contain coarser and looser sediments than those of unspawned streambed areas, and display a dune-like shape with an amplitude and length that vary with fish size, substrate conditions, and flow conditions. Redds increase local bed surface roughness (<10-1 channel width, W), but may reduce the size of macro bedforms by eroding reach-scale topography (100-101W). Research has suggested that spawning may increase flow resistance due to redd form drag, resulting in lower grain shear stress and less particle mobility. Spawning, also prevents streambed armoring by mixing surface and subsurface material, potentially increasing particle mobility. Here we use two-dimensional hydraulic modeling with detailed prespawning and postspawning bathymetries and field observations to test the effect of spawning by small-bodied salmonids on sediment transport. Our results show that topographical roughness from small salmon redds has negligible effects on shear stress at the reach-unit scale, and limited effects at the local scale. Conversely, results indicate sediment mixing reduces armoring and enhances sediment mobility, which increases potential bed load transport by subsequent floods. River restoration in fish-bearing streams should take into consideration the effects of redd excavation on channel stability. This is particularly important for streams that historically supported salmonids and are the focus of habitat restoration actions.

  20. Emerging Vocabulary Learning: From a Perspective of Activities Facilitated by Mobile Devices

    ERIC Educational Resources Information Center

    Hu, Zengning

    2013-01-01

    This paper examines the current mobile vocabulary learning practice to discover how far mobile devices are being used to support vocabulary learning. An activity-centered perspective is undertaken, with the consideration of new practice against existing theories of learning activities including behaviorist activities, constructivist activities,…

  1. Study of the Electrophoretic Behavior of Cephalosporins by Capillary Zone Electrophoresis

    PubMed Central

    Hancu, Gabriel; Sasebeşi, Adina; Rusu, Aura; Kelemen, Hajnal; Ciurba, Adriana

    2015-01-01

    Purpose: The aim of the study was the characterization of the electrophoretic behavior of cephalosporins from different generation having different structural characteristics in order to develop a rapid, simple and efficient capillary electrophoretic method for their identification and simultaneous separation from complex mixtures. Methods: Ten cephalosporin derivatives (cefaclor, cefadroxil, cefalexin, cefazolin, cefoxitin, cefuroxime, cefoperazone, cefotaxime, ceftazidime, ceftriaxone) were analyzed by capillary zone electrophoresis using different background electrolyte solutions at different pH values. Electrophoretic mobilities of the analytes were calculated, the influence of the electrophoretic parameteres on the separation was established and the analytical conditions were optimized. Results: Taking into consideration their structural and chemical properties cephalosporins can be detected over a pH range between 6 and 10. The best results were obtained using a buffer solution containing 25 mM disodium hydrogenophosphate - 25 mM sodium dihydrogenophosphate, at a pH – 7.00, + 25 kV voltage at a temperature of 25 °C, UV detection at 210 nm. Using the optimized analytical conditions we achieved the simultaneous baseline separation for seven cephalosporins in less then 10 minutes. Conclusion: Using the described optimized electrophoretic procedures, capillary electrophoresis can be used for the identification and determination of cephalosporins in formulated pharmaceutical products and for their separation from complex mixtures. PMID:26236661

  2. Tunable electrophoretic separations using a scalable, fabric-based platform.

    PubMed

    Narahari, Tanya; Dendukuri, Dhananjaya; Murthy, Shashi K

    2015-02-17

    There is a rising need for low-cost and scalable platforms for sensitive medical diagnostic testing. Fabric weaving is a mature, scalable manufacturing technology and can be used as a platform to manufacture microfluidic diagnostic tests with controlled, tunable flow. Given its scalability, low manufacturing cost (<$0.25 per device), and potential for patterning multiplexed channel geometries, fabric is a viable platform for the development of analytical devices. In this paper, we describe a fabric-based electrophoretic platform for protein separation. Appropriate yarns were selected for each region of the device and weaved into straight channel electrophoretic chips in a single step. A wide dynamic range of analyte molecules ranging from small molecule dyes (<1 kDa) to macromolecule proteins (67-150 kDa) were separated in the device. Individual yarns behave as a chromatographic medium for electrophoresis. We therefore explored the effect of yarn and fabric parameters on separation resolution. Separation speed and resolution were enhanced by increasing the number of yarns per unit area of fabric and decreasing yarn hydrophilicity. However, for protein analytes that often require hydrophilic, passivated surfaces, these effects need to be properly tuned to achieve well-resolved separations. A fabric device tuned for protein separations was built and demonstrated. As an analytical output parameter for this device, the electrophoretic mobility of a sedimentation marker, Naphthol Blue Black bovine albumin in glycine-NaOH buffer, pH 8.58 was estimated and found to be -2.7 × 10(-8) m(2) V(-1) s(-1). The ability to tune separation may be used to predefine regions in the fabric for successive preconcentrations and separations. The device may then be applied for the multiplexed detection of low abundance proteins from complex biological samples such as serum and cell lysate.

  3. Electrophoretic karyotypes of some related Mucor species.

    PubMed

    Nagy, A; Palagyi, Z; Vastag, M; Ferenczy, L; Vágvölgyi, C

    2000-07-01

    Contour clamped homogeneous electric field (CHEF) gel electrophoresis was used to obtain electrophoretic karyotypes from nine Mucor strains representing five different species (M. bainieri, M. circinelloides, M. mucedo, M. plumbeus and M. racemosus). The chromosomal banding patterns revealed high variability among the isolates. The sizes of the DNA in the Mucor chromosomes were estimated to be between 2.5 and 8.7 Mb. The total genome sizes were calculated to be between 30.0 and 44.7 Mb. The applicability of these electrophoretic karyotypes for the investigation of genome structure, for strain identification and for species delimitation is considered.

  4. Heterogeneity of adenovirus type 5 E1A proteins: multiple serine phosphorylations induce slow-migrating electrophoretic variants but do not affect E1A-induced transcriptional activation or transformation.

    PubMed Central

    Richter, J D; Slavicek, J M; Schneider, J F; Jones, N C

    1988-01-01

    The 289-amino-acid product encoded by the adenovirus E1A 13S mRNA has several pleiotropic activities, including transcriptional activation, transcriptional repression, and when acting in concert with certain oncogene products, cell transformation. In all cell types in which E1A has been introduced (except bacteria), E1A protein is extensively posttranslationally modified to yield several isoelectric and molecular weight variants. The most striking variant is one that has a retarded mobility, by about Mr = 2,000, in sodium dodecyl sulfate gels. We have investigated the nature of this modification and have assessed its importance for E1A activity. Phosphorylation is responsible for the altered mobility of E1A, since acid phosphatase treatment eliminates the higher apparent molecular weight products. By using several E1A deletion mutants, we show that at least two seryl residues, residing between residues 86 and 120 and 224 and 289, are the sites of phosphorylation and that each phosphorylation can independently induce the mobility shift. However, E1A mutants lacking these seryl residues transcriptionally activate the adenovirus E3 and E2A promoters and transform baby rat kidney cells to near wild-type levels. Images PMID:2835499

  5. Adaptive Activity and Environment Recognition for Mobile Phones

    PubMed Central

    Parviainen, Jussi; Bojja, Jayaprasad; Collin, Jussi; Leppänen, Jussi; Eronen, Antti

    2014-01-01

    In this paper, an adaptive activity and environment recognition algorithm running on a mobile phone is presented. The algorithm makes inferences based on sensor and radio receiver data provided by the phone. A wide set of features that can be extracted from these data sources were investigated, and a Bayesian maximum a posteriori classifier was used for classifying between several user activities and environments. The accuracy of the method was evaluated on a dataset collected in a real-life trial. In addition, comparison to other state-of-the-art classifiers, namely support vector machines and decision trees, was performed. To make the system adaptive for individual user characteristics, an adaptation algorithm for context model parameters was designed. Moreover, a confidence measure for the classification correctness was designed. The proposed adaptation algorithm and confidence measure were evaluated on a second dataset obtained from another real-life trial, where the users were requested to provide binary feedback on the classification correctness. The results show that the proposed adaptation algorithm is effective at improving the classification accuracy. PMID:25372620

  6. Adaptive activity and environment recognition for mobile phones.

    PubMed

    Parviainen, Jussi; Bojja, Jayaprasad; Collin, Jussi; Leppänen, Jussi; Eronen, Antti

    2014-11-03

    In this paper, an adaptive activity and environment recognition algorithm running on a mobile phone is presented. The algorithm makes inferences based on sensor and radio receiver data provided by the phone. A wide set of features that can be extracted from these data sources were investigated, and a Bayesian maximum a posteriori classifier was used for classifying between several user activities and environments. The accuracy of the method was evaluated on a dataset collected in a real-life trial. In addition, comparison to other state-of-the-art classifiers, namely support vector machines and decision trees, was performed. To make the system adaptive for individual user characteristics, an adaptation algorithm for context model parameters was designed. Moreover, a confidence measure for the classification correctness was designed. The proposed adaptation algorithm and confidence measure were evaluated on a second dataset obtained from another real-life trial, where the users were requested to provide binary feedback on the classification correctness. The results show that the proposed adaptation algorithm is effective at improving the classification accuracy.

  7. Combined electrophoretic-separation and electrospray method and system

    DOEpatents

    Smith, R.D.; Olivares, J.A.

    1989-06-27

    A system and method for analyzing molecular constituents of a composition sample includes: forming a solution of the sample, separating the solution by capillary zone electrophoresis into an eluent of constituents longitudinally separated according to their relative electrophoretic mobilities, electrospraying the eluent to form a charged spray in which the molecular constituents have a temporal distribution; and detecting or collecting the separated constituents in accordance with the temporal distribution in the spray. A first high-voltage (e.g., 5--100 kVDC) is applied to the solution. The spray is charged by applying a second high voltage (e.g., [+-]2--8 kVDC) between the eluent at the capillary exit and a cathode spaced in front of the exit. A complete electrical circuit is formed by a conductor which directly contacts the eluent at the capillary exit. 10 figs.

  8. Separation of aracytidine and cytidine by capillary electrophoretic techniques.

    PubMed

    Krivánková, L; Kostálová, A; Vargas, G; Havel, J; Bocek, P

    1996-12-01

    Aracytidine (cytarabine, 1-beta-D-arabinofuranosylcytosine) is a synthetic analog of cytidine in which ribose is substituted by arabinose; it is used as a drug for the treatment of leukemia. A fast and reliable capillary electrophoretic method for the analysis of cytarabine and cytidine is described. The procedure utilizes the interactions with sodium dodecyl sulfate (SDS) micelles and borate, present in the background electrolyte, for the mobilization and selective separation of the analytes. The detection is carried out by UV absorbance at 275 nm. The method was applied both to pharmaceutical preparations and human serum. Analysis of an untreated serum requires 15 min; the detection limit is 0.8 microgram/mL and the relative standard deviation (RSD) is 5.3%.

  9. Combined electrophoretic-separation and electrospray method and system

    DOEpatents

    Smith, Richard D.; Olivares, Jose A.

    1989-01-01

    A system and method for analyzing molecular constituents of a composition sample includes: forming a solution of the sample, separating the solution by capillary zone electrophoresis into an eluent of constituents longitudinally separated according to their relative electrophoretic mobilities, electrospraying the eluent to form a charged spray in which the molecular constituents have a temporal distribution; and detecting or collecting the separated constituents in accordance with the temporal distribution in the spray. A first high-voltage (e.g., 5-100 KVDC) is applied to the solution. The spray is charged by applying a second high voltage (e.g., .+-.2-8 KVDC) between the eluent at the capillary exit and a cathode spaced in front of the exit. A complete electrical circuit is formed by a conductor which directly contacts the eluent at the capillary exit.

  10. Electrophoretic purification of cells in space - Evaluation of results from STS-3

    NASA Technical Reports Server (NTRS)

    Sarnoff, B. E.; Kunze, M. E.; Todd, P.

    1983-01-01

    The procedure and results of Electrophoresis Equipment Verification Test, designed to examine electrophoretic behavior of animal cells is suspension more concentrated than possible on earth and flown on the Shuttle flight STS-3, were discussed. Ground-based laboratory values of electrophoretic mobilities of a mixture of human and rabbit aldehyde-fixed red blood cells (RBC) were compared with those recorded at 11 minute intervals on the Shuttle STS-3. RBC migration and separation observed through photographic records were not as expected. However, cell mobilities and migrating band profiles were consistent with the results of laboratory simulation experiments. It was concluded that zero G electrophoresis of very high concentrations (1 x 10 to the 9th) is possible and similar to electrophoresis of normal cell concentrations on earth.

  11. The Effectiveness of WhatsApp Mobile Learning Activities Guided by Activity Theory on Students' Knowledge Management

    ERIC Educational Resources Information Center

    Barhoumi, Chokri

    2015-01-01

    This research paper explores the effectiveness of using mobile technologies to support a blended learning course titled Scientific Research Methods in Information Science. Specifically, it discusses the effects of WhatsApp mobile learning activities guided by activity theory on students' knowledge Management (KM). During the 2014 academic year,…

  12. Active object programming for military autonomous mobile robot software prototyping

    NASA Astrophysics Data System (ADS)

    Cozien, Roger F.

    2001-10-01

    While designing mobile robots, we do think that the prototyping phase is really critical. Good and clever choices have to be made. Indeed, we may not easily upgrade such robots, and most of all, when the robot is on its own, any change in both the software and the physical body is going to be very difficult, if not impossible. Thus, a great effort has to be made when prototyping the robot. Furthermore, I think that the kind of programming is very important. If your programming model is not expressive enough, you may experience a great deal of difficulties to add all the features you want, in order to give your robot reactiveness and decision making autonomy. Moreover, designing, and prototyping the on-board software of a reactive robot brings other difficulties. A reactive robot does not include any matter of rapidity. A reactive system is a system able to respond to a huge panel of situations of which it does not have the schedule. In other words, for instance, the robot does not know when a particular situation may occur, and overall, what it would be doing at this time, and what would be its internal state. This kind of robot must be able to take a decision and to act even if they do not have all the contextual information. To do so, we use a computer language named oRis featuring object and active object oriented programming, but also parallel and dynamic code, (the code can be changed during its own execution). This last point has been made possible because oRis is fully interpreted. However oRis may call fully compiled code, but also Prolog and Java code. An oRis program may be distributed on several computers using TCP/IP network connections. The main issue in this paper is to show how active objet oriented programming, as a modern extension of object oriented programming, may help us in designing autonomous mobile robots. Based on a fully parallel software programming, an active object code allows us to give many features to a robot, and to easily solve

  13. Active objects programming for military autonomous mobile robots software prototyping

    NASA Astrophysics Data System (ADS)

    Cozien, Roger F.

    2001-09-01

    While designing mobile robots, we do think that the prototyping phase is really critical. Good and clever choices have to be made. Indeed, we may not easily upgrade such robots, and most of all, when the robot is on its own, any change in both the software and the physical body is going to be very difficult, if not impossible. Thus, a great effort has to be made when prototyping the robot. Furthermore, I think that the kind of programming is very important. If your programming model is not expressive enough, you may experience a great deal of difficulties to add all the features you want, in order to give your robot reactiveness and decision making autonomy. Moreover, designing, and prototyping the on-board software of a reactive robot brings other difficulties. A reactive robot does not include any matter of rapidity. A reactive system is a system able to respond to a huge pannel of situations of which it does not have the schedule. In other words, for instance, the robot does not know when a particular situation may occur, and overall, what it would be doing at this time, and what would be its internal state. This kind of robot must be able to take a decision and to act even if they do not have all the contextual information. To do so, we use a computer language named oRis featuring object and active object oriented programming, but also parallel and dynamic code, (the code can be changed during its own execution). This last point has been made possible because oRis is fully interpreted. However oRis may call fully compiled code, but also Prolog and Java code. An oRis program may be distributed on several computers using TCP/IP network connections. The main issue in this paper is to show how active objet oriented programming, as a modern extension of object oriented programming, may help us in designing autonomous mobile robots. Based on a fully parallel software programming, an active object code allows us to give many features to a robot, and to easily solve

  14. Impaired voluntary neuromuscular activation limits muscle power in mobility-limited older adults

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background. Age-related alterations of neuromuscular activation may contribute to deficits in muscle power and mobility function. This study assesses whether impaired activation of the agonist quadriceps and antagonist hamstrings, including amplitude- and velocity-dependent characteristics of activa...

  15. Effect of structured physical activity on respiratory outcomes in sedentary elderly adults with mobility limitations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    OBJECTIVES: To evaluate the effect of structured physical activity on respiratory outcomes in community dwelling elderly adults with mobility limitations. DESIGN: Multicenter, randomized trial of physical activity vs health education, with respiratory variables prespecified as tertiary outcomes over...

  16. Failure to Confirm the Macrophage Electrophoretic Mobility Test in Cancer

    PubMed Central

    Forrester, J. A.; Dando, P. M.; Smith, W. J.; Turberville, C.

    1977-01-01

    A series of patients with a variety of histopathologically confirmed cancers have been examined using the MOD-MEM test as described by Pritchard et al. (1973). Despite the closest possible adherence to the experimental protocols recommended by these authors, no positive reactions to the test were observed in this series: neither were we able to demonstrate the release of a “macrophage-slowing factor” by a panel of normal donors when challenged with tubercle PPD. We conclude that the test has no present application to the diagnosis of cancer.

  17. Electrophoretic mobility of magnetite particles in high temperature water

    SciTech Connect

    Vidojkovic, Sonja; Rodriguez-Santiago, V; Fedkin, Mark V.; Wesolowski, David J; Lvov, Serguei N.

    2011-01-01

    Magnetite(Fe3O4) isoneofthemostcommonoxidesformingdepositsandparticulatephasesin industrialhightemperaturewatercircuits.Itscolloidalcharacteristicsplayaprincipalroleinthe mechanismofdepositformationandcanbeusedascontrollingfactorstopreventorminimizedeposit formationanddamageofindustrialpipelinesduetounder-depositcorrosion.Inthisstudy,ahigh temperatureparticleelectrophoresistechniquewasemployedtomeasurethezetapotentialatthe magnetite/waterinterface the parameterthatcontrolscolloidalstabilityofparticles,theiraggrega- tion, anddeposition.Themeasurementsweremadeattemperaturesupto200 1C overawiderangeofpH. The isoelectricpointsofmagnetite,atwhichthedepositionofparticlesisincreased,weredeterminedatpH 6.35, 6.00,5.25,and5.05fortemperatures25,100,150,and200 1C, respectively.Theobserved temperaturedependenceofzetapotentialandtheisoelectricpHpointofmagnetitecanhelptoexplain the extentofinteractionsbetweenthecolloidalparticlesandthesteelwallsurfacesunderhydro- thermalconditions,andindicatemethodsforcontrollingandmitigatingoxidedepositioninhigh temperaturewatercycles.

  18. SEM Analysis of Electrophoretically-Deposited Nanoparticle Films

    NASA Astrophysics Data System (ADS)

    Verma, Neil

    Cobalt ferrite nanoparticles (20 nm) were synthesized and electrophoretically deposited onto aluminum foil, graphite paper, and carbon felt in order to study its potential as a cost-effective electrocatalyst for the oxidation of ammonium sulfite to ammonium sulfate in a proposed sulfur ammonia thermochemical cycle. Scanning electron microscopy and linear sweep voltammetry were used to characterize the deposited films and investigate their electrochemical activity. Furthermore, the effects of electrophoretic deposition conditions on deposit morphology and subsequently the effects of deposit morphology on electrochemical activity in 2 M ammonium sulfite were studied to better understand how to improve electrocatalysts. It was found that there is a critical deposit thickness for each substrate, where additional deposited particles reduce overall electrocatalytic activity of the deposits. For graphite paper, this thickness was estimated to be 3 particle layers for the EPD conditions studied. The 3 particle layer film on graphite paper resulted in a 5.5 fold increase in current density from a blank graphite paper substrate. For carbon felt, the deposit thickness threshold was calculated to be 0.13 of a particle layer for the EPD conditions studied. Moreover, this film was found to have a 4.3 fold increase in current density from a blank carbon felt substrate.

  19. Electrostatic properties of maghemite (γ- Fe(2)O(3)) nanocrystalline quantum dots determined by electrophoretic deposition.

    PubMed

    Islam, Mohammad A; Xia, Shengguo

    2009-07-15

    We applied a DC electric field between two flat electrodes to attract thermally charged maghemite (γ-Fe(2)O(3)) nanocrystalline quantum dots dissolved in hexane to form smooth, robust, large area and apparently identical films of equal thickness on both electrodes. Visible microscopy, scanning electron microscopy, atomic force microscopy and profilometry showed that the electrophoretically deposited dot films were very smooth with an rms roughness of ∼10 nm for ∼0.2 µm thick films. The films were of high quality. They did not re-dissolve in hexane (as do those formed by dry casting), which is a good solvent for these dots, or in common cleaning solvents such as water, alcohols and acetone. The deposition on both electrodes implies there are both positively and negatively thermally charged dots, unlike conventional electrophoretic deposition. We used simple thermodynamics to explain the results of electrophoretic deposition macroscopically. To connect the macroscopic nature of the deposition to the microscopic nature of the dots we performed electrophoretic mobility measurements of the dots and the results seem to complement the thermodynamic treatment.

  20. Electrostatic properties of maghemite (γ- Fe2O3) nanocrystalline quantum dots determined by electrophoretic deposition

    NASA Astrophysics Data System (ADS)

    Islam, Mohammad A.; Xia, Shengguo

    2009-07-01

    We applied a DC electric field between two flat electrodes to attract thermally charged maghemite (γ-Fe2O3) nanocrystalline quantum dots dissolved in hexane to form smooth, robust, large area and apparently identical films of equal thickness on both electrodes. Visible microscopy, scanning electron microscopy, atomic force microscopy and profilometry showed that the electrophoretically deposited dot films were very smooth with an rms roughness of ~10 nm for ~0.2 µm thick films. The films were of high quality. They did not re-dissolve in hexane (as do those formed by dry casting), which is a good solvent for these dots, or in common cleaning solvents such as water, alcohols and acetone. The deposition on both electrodes implies there are both positively and negatively thermally charged dots, unlike conventional electrophoretic deposition. We used simple thermodynamics to explain the results of electrophoretic deposition macroscopically. To connect the macroscopic nature of the deposition to the microscopic nature of the dots we performed electrophoretic mobility measurements of the dots and the results seem to complement the thermodynamic treatment.

  1. Electrostatic properties of maghemite (γ- Fe(2)O(3)) nanocrystalline quantum dots determined by electrophoretic deposition.

    PubMed

    Islam, Mohammad A; Xia, Shengguo

    2009-07-15

    We applied a DC electric field between two flat electrodes to attract thermally charged maghemite (γ-Fe(2)O(3)) nanocrystalline quantum dots dissolved in hexane to form smooth, robust, large area and apparently identical films of equal thickness on both electrodes. Visible microscopy, scanning electron microscopy, atomic force microscopy and profilometry showed that the electrophoretically deposited dot films were very smooth with an rms roughness of ∼10 nm for ∼0.2 µm thick films. The films were of high quality. They did not re-dissolve in hexane (as do those formed by dry casting), which is a good solvent for these dots, or in common cleaning solvents such as water, alcohols and acetone. The deposition on both electrodes implies there are both positively and negatively thermally charged dots, unlike conventional electrophoretic deposition. We used simple thermodynamics to explain the results of electrophoretic deposition macroscopically. To connect the macroscopic nature of the deposition to the microscopic nature of the dots we performed electrophoretic mobility measurements of the dots and the results seem to complement the thermodynamic treatment. PMID:21828514

  2. Mobilization of hepatic calcium pools by platelet activating factor

    SciTech Connect

    Lapointe, D.S.; Hanahan, D.J.; Olson, M.S.

    1987-03-24

    In the perfused rat liver, platelet activating factor, 1-O-hexadecyl-2-acetyl-sn-glycero-3-phosphocholine (AGEPC), infusion produces an extensive but transient glycogenolytic response which at low AGEPC concentrations is markedly dependent upon the perfusate calcium levels. The role of calcium in the glycogenolytic response of the liver to AGEPC was investigated by assessing the effect of AGEPC on various calcium pools in the intact liver. Livers from fed rats were equilibrated with /sup 45/Ca/sup 2 +/, and the kinetics of /sup 45/Ca/sup 2 +/ efflux were determined in control, AGEPC-stimulated, and phenylephrine-stimulated livers during steady-state washout of /sup 45/Ca/sup 2 +/. AGEPC treatment had only a slight if any effect on the pattern of steady-state calcium efflux from the liver, as opposed to major perturbations in the pattern of calcium efflux effected by the ..cap alpha..-adrenergic agonist phenylephrine. Infusion of short pulses of AGEPC during the washout of /sup 45/Ca/sup 2 +/ from labeled livers caused a transient release of /sup 45/Ca/sup 2 +/ which was not abolished at low calcium concentrations in the perfusate. Infusion of latex beads, which are removed by the reticuloendothelial cells, caused the release of hepatic /sup 45/Ca/sup 2 +/ in a fashion similar to the case with AGEPC. The findings indicate that AGEPC does not perturb a major pool of calcium within the liver as occurs upon ..cap alpha..-adrenergic stimulation; it is likely that AGEPC mobilizes calcium from a smaller yet very important pool, very possibly from nonparenchymal cells in the liver.

  3. Activation energy associated with the electromigration of oligosaccharides through viscosity modifier and polymeric additive containing background electrolytes.

    PubMed

    Kerékgyártó, Márta; Járvás, Gábor; Novák, Levente; Guttman, András

    2016-02-01

    The activation energy related to the electromigration of oligosaccharides can be determined from their measured electrophoretic mobilities at different temperatures. The effects of a viscosity modifier (ethylene glycol) and a polymeric additive (linear polyacrylamide) on the electrophoretic mobility of linear sugar oligomers with α1-4 linked glucose units (maltooligosaccharides) were studied in CE using the activation energy concept. The electrophoretic separations of 8-aminopyrene-1,3,6-trisulfonate-labeled maltooligosaccharides were monitored by LIF detection in the temperature range of 20-50°C, using either 0-60% ethylene glycol (viscosity modifier) or 0-3% linear polyacrylamide (polymeric additive) containing BGEs. Activation energy curves were constructed based on the slopes of the Arrhenius plots. With the use of linear polyacrylamide additive, solute size-dependent activation energy variations were found for the maltooligosaccharides with polymerization degrees below and above maltoheptaose (DP 7), probably due to molecular conformation changes and possible matrix interaction effects.

  4. Usability of Mobile Phones in Physical Activity-Rrelated Research: A Systematic Review

    ERIC Educational Resources Information Center

    Monroe, Courtney M.; Thompson, Dixie L.; Bassett, David R., Jr.; Fitzhugh, Eugene C.; Raynor, Hollie A.

    2015-01-01

    Background: The use of mobile phones for physical activity (PA) promotion and assessment represents an attractive research area because this technology is characterized by a widespread reach and dynamic features. Purpose: The purpose of this study was to conduct a systematic review of mobile phone-based approaches for encouraging and assessing PA.…

  5. The Experience of Choice in Physical Activity Contexts for Adults with Mobility Impairments

    ERIC Educational Resources Information Center

    Morphy, Lorraine Y.; Goodwin, Donna L.

    2012-01-01

    This exploratory study described the experiences of choice in physical activity contexts for adults with mobility impairments. The experiences of 3 female and 2 males with mobility impairments between 18 and 23 years of age were described using the interpretive phenomenological methods of individual interviews, written stories, and field notes.…

  6. Using Mobile Phones for Vocabulary Activities: Examining the Effect of the Platform

    ERIC Educational Resources Information Center

    Stockwell, Glenn

    2010-01-01

    While problems such as small screens and inconvenient keypads have been pointed out by researchers (e.g., Thornton & Houser, 2002), we still have little knowledge of how the mobile platform affects the way in which activities are completed and how learners make decisions about using mobile phones. Stockwell (2007b) provided preliminary evidence…

  7. Embodied Computation: An Active-Learning Approach to Mobile Robotics Education

    ERIC Educational Resources Information Center

    Riek, L. D.

    2013-01-01

    This paper describes a newly designed upper-level undergraduate and graduate course, Autonomous Mobile Robots. The course employs active, cooperative, problem-based learning and is grounded in the fundamental computational problems in mobile robotics defined by Dudek and Jenkin. Students receive a broad survey of robotics through lectures, weekly…

  8. Investigating Acceptance toward Mobile Learning to Assist Individual Knowledge Management: Based on Activity Theory Approach

    ERIC Educational Resources Information Center

    Liaw, Shu-Sheng; Hatala, Marek; Huang, Hsiu-Mei

    2010-01-01

    Mobile devices could facilitate human interaction and access to knowledge resources anytime and anywhere. With respect to wide application possibilities of mobile learning, investigating learners' acceptance towards it is an essential issue. Based on activity theory approach, this research explores positive factors for the acceptance of m-learning…

  9. Developing a Mobile Learning Management System for Outdoors Nature Science Activities Based on 5E Learning Cycle

    ERIC Educational Resources Information Center

    Lai, Ah-Fur; Lai, Horng-Yih; Chuang, Wei-Hsiang; Wu, Zih-Heng

    2015-01-01

    Traditional outdoor learning activities such as inquiry-based learning in nature science encounter many dilemmas. Due to prompt development of mobile computing and widespread of mobile devices, mobile learning becomes a big trend on education. The main purpose of this study is to develop a mobile-learning management system for overcoming the…

  10. The association between objectively measured physical activity and life-space mobility among older people.

    PubMed

    Tsai, L-T; Portegijs, E; Rantakokko, M; Viljanen, A; Saajanaho, M; Eronen, J; Rantanen, T

    2015-08-01

    The purpose of this cross-sectional study was to investigate the association between objectively measured physical activity and life-space mobility in community-dwelling older people. Life-space refers to the spatial area a person purposefully moves through in daily life (bedroom, home, yard, neighborhood, town, and beyond) and life-space mobility to the frequency of travel and the help needed when moving through different life-space areas. The study population comprised community-living 75- to 90-year-old people {n = 174; median age 79.7 [interquartile range (IQR) 7.1]}, participating in the accelerometer substudy of Life-Space Mobility in Old Age (LISPE) project. Step counts and activity time were measured by an accelerometer (Hookie "AM20 Activity Meter") for 7 days. Life-space mobility was assessed with Life-Space Assessment (LSA) questionnaire. Altogether, 16% had a life-space area restricted to the neighborhood when moving independently. Participants with a restricted life space were less physically active and about 70% of them had exceptionally low values in daily step counts (≤ 615 steps) and moderate activity time (≤ 6.8 min). Higher step counts and activity time correlated positively with life-space mobility. Prospective studies are needed to clarify the temporal order of low physical activity level and restriction in life-space mobility.

  11. A mobile system for active otpical pollution monitoring

    NASA Technical Reports Server (NTRS)

    Sunesson, A.; Edner, H.; Svanberg, S.; Uneus, L.; Wendt, W.; Fredriksson, K.

    1986-01-01

    The remote monitoring of atmospheric pollutants can now be performed in several ways. Laser radar techniques have proven their ability to reveal the spatial distribution of different species or particles. Classical optical techniques can also be used, but yield the average concentration over a given path and hence no range resolution. One such technique is Differential Optical Absorption Spectroscopy, DOAS. Such schemes can be used to monitor paths that a preliminary lidar investigation has shown to be of interest. Having previously had access to a mobile lidar system, a new system has been completed. The construction builds on experience from using the other system and it is meant to be more of a mobile optical laboratory than just a lidar system. A complete system description is given along with some preliminary usage. Future uses are contemplated.

  12. Modified Advanced Crew Escape Suit Intravehicular Activity Suit for Extravehicular Activity Mobility Evaluations

    NASA Technical Reports Server (NTRS)

    Watson, Richard D.

    2014-01-01

    The use of an intravehicular activity (IVA) suit for a spacewalk or extravehicular activity (EVA) was evaluated for mobility and usability in the Neutral Buoyancy Laboratory (NBL) environment at the Sonny Carter Training Facility near NASA Johnson Space Center in Houston, Texas. The Space Shuttle Advanced Crew Escape Suit was modified to integrate with the Orion spacecraft. The first several missions of the Orion Multi-Purpose Crew Vehicle will not have mass available to carry an EVA-specific suit; therefore, any EVA required will have to be performed by the Modified Advanced Crew Escape Suit (MACES). Since the MACES was not designed with EVA in mind, it was unknown what mobility the suit would be able to provide for an EVA or whether a person could perform useful tasks for an extended time inside the pressurized suit. The suit was evaluated in multiple NBL runs by a variety of subjects, including crewmembers with significant EVA experience. Various functional mobility tasks performed included: translation, body positioning, tool carrying, body stabilization, equipment handling, and tool usage. Hardware configurations included with and without Thermal Micrometeoroid Garment, suit with IVA gloves and suit with EVA gloves. Most tasks were completed on International Space Station mock-ups with existing EVA tools. Some limited tasks were completed with prototype tools on a simulated rocky surface. Major findings include: demonstrating the ability to weigh-out the suit, understanding the need to have subjects perform multiple runs prior to getting feedback, determining critical sizing factors, and need for adjusting suit work envelope. Early testing demonstrated the feasibility of EVA's limited duration and limited scope. Further testing is required with more flight-like tasking and constraints to validate these early results. If the suit is used for EVA, it will require mission-specific modifications for umbilical management or Primary Life Support System integration

  13. Scanning and storage of electrophoretic records

    DOEpatents

    McKean, Ronald A.; Stiegman, Jeff

    1990-01-01

    An electrophoretic record that includes at least one gel separation is mounted for motion laterally of the separation record. A light source is positioned to illuminate at least a portion of the record, and a linear array camera is positioned to have a field of view of the illuminated portion of the record and orthogonal to the direction of record motion. The elements of the linear array are scanned at increments of motion of the record across the field of view to develop a series of signals corresponding to intensity of light at each element at each scan increment.

  14. Isolation and characterization of an utero-active compound from Agave americana.

    PubMed

    Basilio, C M; Seyler, L; Bernstein, J; Castro de la Mata, R

    1989-12-01

    Crude extracts of Agave americana contain two utero-active compounds. One of these, tentatively named "Fraction B", has been purified to chromatographic homogeneity. Its pharmacological actions are similar to those of acetylcholine. However its chromatographic and electrophoretic mobilities are different. Some chemical properties of fraction B are compatible with the structure of an acyl derivative of choline different from acetylcholine.

  15. Variation of electrophoretic karyotypes among clinical isolates of Candida albicans.

    PubMed Central

    Merz, W G; Connelly, C; Hieter, P

    1988-01-01

    Orthogonal-field-alternation gel electrophoresis was used to compare clinical isolates of Candida albicans by resolving chromosome-sized DNA molecules into an electrophoretic karyotype. Seven to nine bands were observed among isolates recovered from 17 patients. In addition, 14 distinct electrophoretic patterns were noted among the isolates from these patients. In a given individual, isolates were likely to have identical electrophoretic patterns. Therefore, the electrophoretic karyotype patterns demonstrated by orthogonal-field-alternation gel electrophoresis can be used to designate a strain for epidemiologic studies. Images PMID:3290238

  16. Rapid fabrication of reconstructible hydrogels by electrophoretic microbead adhesion.

    PubMed

    Asoh, Taka-Aki; Kikuchi, Akihiko

    2012-10-14

    Hydrogel constructs were rapidly fabricated via the electrophoretic adhesion of oppositely charged microbeads. The reversible preparation of hydrogel constructs was achieved by the reconstruction of microbead networks.

  17. Neuronal Activity and Glutamate Uptake Decrease Mitochondrial Mobility in Astrocytes and Position Mitochondria Near Glutamate Transporters

    PubMed Central

    Jackson, Joshua G.; O'Donnell, John C.; Takano, Hajime; Coulter, Douglas A.

    2014-01-01

    Within neurons, mitochondria are nonuniformly distributed and are retained at sites of high activity and metabolic demand. Glutamate transport and the concomitant activation of the Na+/K+-ATPase represent a substantial energetic demand on astrocytes. We hypothesized that mitochondrial mobility within astrocytic processes might be regulated by neuronal activity and glutamate transport. We imaged organotypic hippocampal slice cultures of rat, in which astrocytes maintain their highly branched morphologies and express glutamate transporters. Using time-lapse confocal microscopy, the mobility of mitochondria within individual astrocytic processes and neuronal dendrites was tracked. Within neurons, a greater percentage of mitochondria were mobile than in astrocytes. Furthermore, they moved faster and farther than in astrocytes. Inhibiting neuronal activity with tetrodotoxin (TTX) increased the percentage of mobile mitochondria in astrocytes. Mitochondrial movement in astrocytes was inhibited by vinblastine and cytochalasin D, demonstrating that this mobility depends on both the microtubule and actin cytoskeletons. Inhibition of glutamate transport tripled the percentage of mobile mitochondria in astrocytes. Conversely, application of the transporter substrate d-aspartate reversed the TTX-induced increase in the percentage of mobile mitochondria. Inhibition of reversed Na+/Ca2+ exchange also increased the percentage of mitochondria that were mobile. Last, we demonstrated that neuronal activity increases the probability that mitochondria appose GLT-1 particles within astrocyte processes, without changing the proximity of GLT-1 particles to VGLUT1. These results imply that neuronal activity and the resulting clearance of glutamate by astrocytes regulate the movement of astrocytic mitochondria and suggest a mechanism by which glutamate transporters might retain mitochondria at sites of glutamate uptake. PMID:24478345

  18. Effect of affordable technology on physical activity levels and mobility outcomes in rehabilitation: a protocol for the Activity and MObility UsiNg Technology (AMOUNT) rehabilitation trial

    PubMed Central

    Hassett, Leanne; van den Berg, Maayken; Lindley, Richard I; Crotty, Maria; McCluskey, Annie; van der Ploeg, Hidde P; Smith, Stuart T; Schurr, Karl; Killington, Maggie; Bongers, Bert; Howard, Kirsten; Heritier, Stephane; Togher, Leanne; Hackett, Maree; Treacy, Daniel; Dorsch, Simone; Wong, Siobhan; Scrivener, Katharine; Chagpar, Sakina; Weber, Heather; Pearson, Ross; Sherrington, Catherine

    2016-01-01

    Introduction People with mobility limitations can benefit from rehabilitation programmes that provide a high dose of exercise. However, since providing a high dose of exercise is logistically challenging and resource-intensive, people in rehabilitation spend most of the day inactive. This trial aims to evaluate the effect of the addition of affordable technology to usual care on physical activity and mobility in people with mobility limitations admitted to inpatient aged and neurological rehabilitation units compared to usual care alone. Methods and analysis A pragmatic, assessor blinded, parallel-group randomised trial recruiting 300 consenting rehabilitation patients with reduced mobility will be conducted. Participants will be individually randomised to intervention or control groups. The intervention group will receive technology-based exercise to target mobility and physical activity problems for 6 months. The technology will include the use of video and computer games/exercises and tablet applications as well as activity monitors. The control group will not receive any additional intervention and both groups will receive usual inpatient and outpatient rehabilitation care over the 6-month study period. The coprimary outcomes will be objectively assessed physical activity (proportion of the day spent upright) and mobility (Short Physical Performance Battery) at 6 months after randomisation. Secondary outcomes will include: self-reported and objectively assessed physical activity, mobility, cognition, activity performance and participation, utility-based quality of life, balance confidence, technology self-efficacy, falls and service utilisation. Linear models will assess the effect of group allocation for each continuously scored outcome measure with baseline scores entered as a covariate. Fall rates between groups will be compared using negative binomial regression. Primary analyses will be preplanned, conducted while masked to group allocation and use an

  19. Electrophoretic Porosimetry of Sol-Gels

    NASA Technical Reports Server (NTRS)

    Snow, L. A.; Smith, D. D.; Sibille, L.; Hunt, A. J.; Ng, J.; Rose, M. Franklin (Technical Monitor)

    2000-01-01

    It has been hypothesized that gravity has an effect on the formation and resulting microstructure of sol-gels. In order to more clearly resolve the effect of gravity, pores may be non-destructively analyzed in the wet gel, circumventing the shrinkage and coarsening associated with the drying procedure. We discuss the development of an electrophoretic technique, analogous to affinity chromatography, for the determination of pore size distribution and its application to silica gels. Specifically a monodisperse charged dye is monitored by an optical densitometer as it moves through the wet gel under the influence of an electric field. The transmittance data (output) represents the convolution of the dye concentration profile at the beginning of the run (input) with the pore size distribution (transfer function), i.e. linear systems theory applies. Because of the practical difficulty in producing a delta function input dye profile we prefer instead to use a step function. Average pore size is then related to the velocity of this dye front, while the pore size distribution is related to the spreading of the front. Preliminary results of this electrophoretic porosimetry and its application to ground and space-grown samples will be discussed.

  20. Hydralazine administration activates sympathetic preganglionic neurons whose activity mobilizes glucose and increases cardiovascular function.

    PubMed

    Parker, Lindsay M; Damanhuri, Hanafi A; Fletcher, Sophie P S; Goodchild, Ann K

    2015-04-16

    Hypotensive drugs have been used to identify central neurons that mediate compensatory baroreceptor reflex responses. Such drugs also increase blood glucose. Our aim was to identify the neurochemical phenotypes of sympathetic preganglionic neurons (SPN) and adrenal chromaffin cells activated following hydralazine (HDZ; 10mg/kg) administration in rats, and utilize this and SPN target organ destination to ascribe their function as cardiovascular or glucose regulating. Blood glucose was measured and adrenal chromaffin cell activation was assessed using c-Fos immunoreactivity (-ir) and phosphorylation of tyrosine hydroxylase, respectively. The activation and neurochemical phenotype of SPN innervating the adrenal glands and celiac ganglia were determined using the retrograde tracer cholera toxin B subunit, in combination with in situ hybridization and immunohistochemistry. Blood glucose was elevated at multiple time points following HDZ administration but little evidence of chromaffin cell activation was seen suggesting non-adrenal mechanisms contribute to the sustained hyperglycemia. 16±0.1% of T4-T11 SPN contained c-Fos and of these: 24.3±1.4% projected to adrenal glands and 29±5.5% projected to celiac ganglia with the rest innervating other targets. 62.8±1.4% of SPN innervating adrenal glands were activated and 29.9±3.3% expressed PPE mRNA whereas 53.2±8.6% of SPN innervating celiac ganglia were activated and 31.2±8.8% expressed PPE mRNA. CART-ir SPN innervating each target were also activated and did not co-express PPE mRNA. Neurochemical coding reveals that HDZ administration activates both PPE+SPN, whose activity increase glucose mobilization causing hyperglycemia, as well as CART+SPN whose activity drive vasomotor responses mediated by baroreceptor unloading to raise vascular tone and heart rate.

  1. Change-of-state determination to recognize mobility activities using a BlackBerry smartphone.

    PubMed

    Wu, Hui Hsien; Lemaire, Edward D; Baddour, Natalie

    2011-01-01

    A Wearable Mobility Monitoring System (WMMS) can be a useful tool for rehabilitation decision-making. This paper presents preliminary design and evaluation of a WMMS proof-of-concept system. Software was developed for the BlackBerry 9550, using the integrated three axes accelerometer, GPS, video camera, and timer to identify mobility changes-of-state (CoS) between static activities, walking-related activities, taking an elevator, bathroom activities, working in the kitchen, and meal preparation (five able-bodied subjects). This pilot project provides insight into new algorithms and features that recognize CoS and activities in real-time. Following features extraction from the sensor data, two decision trees were used to distinguish the CoS and activities. Real-time CoS identification triggered BlackBerry video recording for improved mobility context analysis during post-processing. PMID:22255522

  2. Brain activation during visual working memory correlates with behavioral mobility performance in older adults.

    PubMed

    Kawagoe, Toshikazu; Suzuki, Maki; Nishiguchi, Shu; Abe, Nobuhito; Otsuka, Yuki; Nakai, Ryusuke; Yamada, Minoru; Yoshikawa, Sakiko; Sekiyama, Kaoru

    2015-01-01

    Functional mobility and cognitive function often decline with age. We previously found that functional mobility as measured by the Timed Up and Go Test (TUG) was associated with cognitive performance for visually-encoded (i.e., for location and face) working memory (WM) in older adults. This suggests a common neural basis between TUG and visual WM. To elucidate this relationship further, the present study aimed to examine the neural basis for the WM-mobility association. In accordance with the well-known neural compensation model in aging, we hypothesized that "attentional" brain activation for easy WM would increase in participants with lower mobility. The data from 32 healthy older adults were analyzed, including brain activation during easy WM tasks via functional Magnetic Resonance Imaging (fMRI) and mobility performance via both TUG and a simple walking test. WM performance was significantly correlated with TUG but not with simple walking. Some prefrontal brain activations during WM were negatively correlated with TUG performance, while positive correlations were found in subcortical structures including the thalamus, putamen and cerebellum. Moreover, activation of the subcortical regions was significantly correlated with WM performance, with less activation for lower WM performers. These results indicate that older adults with lower mobility used more cortical (frontal) and fewer subcortical resources for easy WM tasks. To date, the frontal compensation has been proposed separately in the motor and cognitive domains, which have been assumed to compensate for dysfunction of the other brain areas; however, such dysfunction was less clear in previous studies. The present study observed such dysfunction as degraded activation associated with lower performance, which was found in the subcortical regions. We conclude that a common dysfunction-compensation activation pattern is likely the neural basis for the association between visual WM and functional mobility.

  3. Electrophoretic Deposition of Carbon Nitride Layers for Photoelectrochemical Applications.

    PubMed

    Xu, Jingsan; Shalom, Menny

    2016-05-25

    Electrophoretic deposition (EPD) is used for the growth of carbon nitride (C3N4) layers on conductive substrates. EPD is fast, environmentally friendly, and allows the deposition of negatively charged C3N4 with different compositions and chemical properties. In this method, C3N4 can be deposited on various conductive substrates ranging from conductive glass and carbon paper to nickel foam possessing complex 3D geometries. The high flexibility of this approach enables us to readily tune the photophysical and photoelectronic properties of the C3N4 electrodes. The advantage of this method was further illustrated by the tailored construction of a heterostructure between two complementary C3N4, with marked photoelectrochemical activity.

  4. The electrophoretically 'slow' and 'fast' forms of the alpha 2-macroglobulin molecule.

    PubMed Central

    Barrett, A J; Brown, M A; Sayers, C A

    1979-01-01

    alpha 2-Macroglobulin (alpha 2M) was isolated from human plasma by a four-step procedure: poly(ethylene glyco) fractionation, gel chromatography, euglobulin precipitation and immunoadsorption. No contaminants were detected in the final preparations by electrophoresis or immunoprecipitation. The protein ran as a single slow band in gel electrophoresis, and was designated 'S-alpha 2M'. S-alpha 2M bound about 2 mol of trypsin/mol. Treatment of S-alpha 2M with a proteinase or ammonium salts produced a form of the molecule more mobile in electrophoresis, and lacking proteinase-binding activity (F-alpha 2M). The electrophoretic mobility of the F-alpha 2M resulting from reaction with NH4+ salts was identical with that of proteinase complexes. We attribute the change in electrophoretic mobility of the alpha 2M to a conformation change, but there was no evidence of a change in pI or Strokes radius. Electrophoresis of S-alpha 2M in the presence of sodium dodecylsulphate gave results consistent with the view that the alpha 2M molecule is a tetramer of identical subunits, assembled as a non-covalent pair of disulphide-linked dimers. Some of the subunits seemed to be 'nicked' into two-thires-length and one-third-length chains, however. This was not apparent with F-alpha 2M produced by ammonium salts. F-alpha 2M produced by trypsin showed two new bands attributable to cleavage of the subunit polypeptide chain near the middle. Immunoassays of F-alpha 2M gave 'rockets' 12-29% lower than those with S-alpha 2M. The nature of the interactions between subunits in S-alpha 2M and F-alpha 2M was investigated by treating each form with glutaraldehyde before electrophoresis in the presence of sodium dodecyl sulphate. A much greater degree of cross-linking was observed with the F-alpha 2M, indicating that the subunits interact most closely in this form of the molecule. Exposure of S-alpha 2M to 3 M-urea or pH3 resulted in dissociation to the disulphide-bonded half-molecules; these did not

  5. A new high activity plasma cholinesterase variant.

    PubMed Central

    Krause, A; Lane, A B; Jenkins, T

    1988-01-01

    A South African Afrikaans speaking family is reported in which a new high activity plasma cholinesterase variant was found to occur in the mother and son. The variant has the same electrophoretic mobility as the "usual' enzyme, but greater heat stability. Its higher specific activity is associated with a normal number of enzyme molecules. The variant may be inherited as a dominant trait, though its locus is uncertain. Images PMID:3225823

  6. Investigation of the free flow electrophoretic process

    NASA Technical Reports Server (NTRS)

    Weiss, R. A.; Lanham, J. W.; Richman, D. W.; Walker, C. D.

    1980-01-01

    The effects of gravity on the free flow electrophoretic process was demonstrated. The free flow electrophoresis chamber used to demonstrate the effects of gravity on the process was of a proprietary design. This chamber was 120 cm long, 16 cm wide, and 0.15 cm thick. Flow in this chamber was in the upward direction and exited through 197 outlets at the top of the chamber. During electrophoresis a stream of sample was injected into the flow near the bottom of the chamber and an electrical field was applied across the width of the chamber. The field caused a lateral force on particles in the sample proportional to the inherent change of the particle and the electric field strength. Particle lateral velocity was then dependent on the force due to viscous drag which was proportional to particle size and particle shape dependent.

  7. Chromatographic and electrophoretic approaches in ink analysis.

    PubMed

    Zlotnick, J A; Smith, F P

    1999-10-15

    Inks are manufactured from a wide variety of substances that exhibit very different chemical behaviors. Inks designed for use in different writing instruments or printing methods have quite dissimilar components. Since the 1950s chromatographic and electrophoretic methods have played important roles in the analysis of inks, where compositional information may have bearing on the investigation of counterfeiting, fraud, forgery, and other crimes. Techniques such as paper chromatography and electrophoresis, thin-layer chromatography, high-performance liquid chromatography, gas chromatography, gel electrophoresis, and the relatively new technique of capillary electrophoresis have all been explored as possible avenues for the separation of components of inks. This paper reviews the components of different types of inks and applications of the above separation methods are reviewed. PMID:10572985

  8. Electrophoretic deposition of porous hydroxyapatite scaffold.

    PubMed

    Ma, J; Wang, C; Peng, K W

    2003-09-01

    Bioactive porous hydroxyapatite (HA) scaffold was fabricated using electrophoretic deposition (EPD) technique in the present work. Bulk HA scaffold was achieved by repeated deposition. The green scaffold was sintered at 1200 degrees C to 82% of the theoretical density. Scanning electron microscopy examination and mercury porosimetry measurement have shown that the porosity remains interconnected and a range of pore size from several microns to hundreds of microns was obtained. X-ray diffraction analysis was performed and confirmed that there is no HA decomposition during the sintering process. Mechanical characterization has also shown that the EPD scaffold possesses excellent properties. Cell culturing experiment was carried out and the result shows that the scaffold bioactivity is not only dependent on the interconnectivity of the pores, but also the pore size.

  9. Electrophoretic Deposition on Porous Non-Conductors

    NASA Technical Reports Server (NTRS)

    Compson, Charles; Besra, Laxmidhar; Liu, Meilin

    2007-01-01

    A method of electrophoretic deposition (EPD) on substrates that are porous and electrically non-conductive has been invented. Heretofore, in order to perform an EPD, it has been necessary to either (1) use a substrate material that is inherently electrically conductive or (2) subject a non-conductive substrate to a thermal and/or chemical treatment to render it conductive. In the present method, instead of relying on the electrical conductivity of the substrate, one ensures that the substrate is porous enough that when it is immersed in an EPD bath, the solvent penetrates throughout the thickness, thereby forming quasi-conductive paths through the substrate. By making it unnecessary to use a conductive substrate, this method simplifies the overall EPD process and makes new applications possible. The method is expected to be especially beneficial in enabling deposition of layers of ceramic and/or metal for chemical and electrochemical devices, notably including solid oxide fuel cells.

  10. SPAR electrophoretic separation experiments, part 2

    NASA Technical Reports Server (NTRS)

    Cosmi, F. M.

    1978-01-01

    The opportunity to use a sounding rocket for separation experiments is a logical continuation of earlier electrophoresis demonstrations and experiments. A free-flow electrophoresis system, developed under the Advanced Applications Flight Experiment (AAFE) Program, was designed so that it would fit into a rocket payload. The SPAR program provides a unique opportunity to complete the intial stages of microgravity testing prior to any Shuttle applications. The objective of the work described in this report was to ensure proper operating parameters for the defined experimental samples to be used in the SPAR Electrophoretic Separation Experiment. Ground based experiments were undertaken not only to define flight parameters but also to serve as a point of comparison for flight results. Possible flight experiment problem areas were also studied such as sample interaction due to sedimentation, concentration effects and storage effects. Late in the program anomalies of field strengths and buffer conductivities were also investigated.

  11. Does quadriceps neuromuscular activation capability explain mobility function among older men and women?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Age-related impairment of neuromuscular activation has been shown to contribute to weakness in older adults. However, it is unclear to what extent impaired neuromuscular activation independently accounts for decline of mobility function. The hypothesis of this study is that capability to produce rap...

  12. Does neuromuscular activation capability explain mobility function among older men and women?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Age-related impairment of neuromuscular activation has been shown to contribute to weakness in older adults. However, it is unclear to what extent impaired neuromuscular activation independently accounts for decline of mobility function. The hypothesis of this study is that capability to produce rap...

  13. Exploration of Tensions in a Mobile-Technology Supported Fieldtrip: An Activity Theory Perspective

    ERIC Educational Resources Information Center

    Lai, Chih-Hung; Chen, Fei-Ching; Yang, Jie-Chi

    2014-01-01

    The purpose of this study was to analyze how mobile technologies were incorporated and implemented in an outdoor learning activity. Two classes of primary school students participated in the experiment. Using activity theory as an analytical framework, it is found that underlying tensions provided rich insights into system dynamics and that…

  14. A Physical Activity Program to Mobilize Older People: A Practical and Sustainable Approach

    ERIC Educational Resources Information Center

    Jancey, Jonine M.; Clarke, Ann; Howat, Peter A.; Lee, Andy H.; Shilton, Trevor; Fisher, John

    2008-01-01

    Purpose: Despite the documented benefits of physical activity, it remains difficult to motivate older adults to start and maintain regular physical activity. This study tested an innovative intervention for mobilizing older adults into a neighborhood-based walking program. Design and Methods: Researchers recruited a total of 260 healthy but…

  15. Dielectrophoretic and electrophoretic force analysis of colloidal fullerenes in a nematic liquid-crystal medium

    NASA Astrophysics Data System (ADS)

    Srivastava, Anoop Kumar; Kim, Miyoung; Kim, Sung Min; Kim, Mi-Kyung; Lee, Kyu; Lee, Young Hee; Lee, Myong-Hoon; Lee, Seung Hee

    2009-11-01

    This research focuses on the electrokinetic motion of fullerenes suspended in liquid crystal host medium, which are investigated in the homogeneously aligned nematic liquid crystal cells driven by in-plane field. We investigated the effect of electrophoretic and dielectrophoretic forces and related parameters of the colloidal fullerenes in liquid crystals. The electrophoretic mobility, zeta potential, and critical voltage have been evaluated. Fullerenes suspended in liquid crystal medium migrated toward the positive electrode, but were pulled back in the opposite direction when the polarity was reversed especially at low frequency range (<5Hz) . At higher electric field and higher frequency ranges, the net displacement of fullerenes has been observed. We demonstrate that the dielectrophoretic force dominated the motion in the colloidal fullerenes by a proper analysis of different electrophoretic parameters. In addition, the electrodynamics of fullerenes was explained by applying the theory of the dielectrophoresis and Schwarz’s formula. We propose a model to estimate the density of fullerenes suspended in liquid crystal medium.

  16. Electrochemically powered self-propelled electrophoretic nanosubmarines

    NASA Astrophysics Data System (ADS)

    Pumera, Martin

    2010-09-01

    In the past few years, we have witnessed rapid developments in the realization of the old nanotechnology dream, autonomous nanosubmarines. These nanomachines are self-powered, taking energy from their environment by electrocatalytic conversion of chemicals present in the solution, self-propelled by flux of the electrons within the submarine and the hydronium ions on the surface of the nanosub, powering it in the direction opposite to that of the flux of the hydronium. These nanosubmarines are responsive to external fields, able to follow complex magnetic patterns, navigate themselves in complex microfluidic channels, follow chemical gradients, carry cargo, and communicate with each other. This minireview focuses on a discussion of the fundamentals of the electrophoretic mechanism underlying the propulsion of this sort of nanosub, as well as a demonstration of the proof-of-concept capabilities of nanosubmarines.In the past few years, we have witnessed rapid developments in the realization of the old nanotechnology dream, autonomous nanosubmarines. These nanomachines are self-powered, taking energy from their environment by electrocatalytic conversion of chemicals present in the solution, self-propelled by flux of the electrons within the submarine and the hydronium ions on the surface of the nanosub, powering it in the direction opposite to that of the flux of the hydronium. These nanosubmarines are responsive to external fields, able to follow complex magnetic patterns, navigate themselves in complex microfluidic channels, follow chemical gradients, carry cargo, and communicate with each other. This minireview focuses on a discussion of the fundamentals of the electrophoretic mechanism underlying the propulsion of this sort of nanosub, as well as a demonstration of the proof-of-concept capabilities of nanosubmarines. In memory of Karel Zeman, Czech animator, who encouraged thousands of young people into science and technology, on the occasion of the 100th

  17. Iterative development of MobileMums: a physical activity intervention for women with young children

    PubMed Central

    2012-01-01

    Background To describe the iterative development process and final version of ‘MobileMums’: a physical activity intervention for women with young children (<5 years) delivered primarily via mobile telephone (mHealth) short messaging service (SMS). Methods MobileMums development followed the five steps outlined in the mHealth development and evaluation framework: 1) conceptualization (critique of literature and theory); 2) formative research (focus groups, n= 48); 3) pre-testing (qualitative pilot of intervention components, n= 12); 4) pilot testing (pilot RCT, n= 88); and, 5) qualitative evaluation of the refined intervention (n= 6). Results Key findings identified throughout the development process that shaped the MobileMums program were the need for: behaviour change techniques to be grounded in Social Cognitive Theory; tailored SMS content; two-way SMS interaction; rapport between SMS sender and recipient; an automated software platform to generate and send SMS; and, flexibility in location of a face-to-face delivered component. Conclusions The final version of MobileMums is flexible and adaptive to individual participant’s physical activity goals, expectations and environment. MobileMums is being evaluated in a community-based randomised controlled efficacy trial (ACTRN12611000481976). PMID:23256730

  18. An upward compatible spectrum sharing architecture for existing, actively planned and emerging mobile satellite systems

    NASA Technical Reports Server (NTRS)

    Azarbar, Bahman

    1990-01-01

    Existing and actively planned mobile satellite systems are competing for a viable share of the spectrum allocated by the International Telecommunications Union (ITU) to the satellite based mobile services in the 1.5/1.6 GHz range. The limited amount of spectrum available worldwide and the sheer number of existing and planned mobile satellite systems dictate the adoption of an architecture which will maximize sharing possibilities. A viable sharing architecture must recognize the operational needs and limitations of the existing systems. Furthermore, recognizing the right of access of the future systems as they will emerge in time, the adopted architecture must allow for additional growth and be amenable to orderly introduction of future systems. An attempt to devise such a sharing architecture is described. A specific example of the application of the basic concept to the existing and planned mobile satellite systems is also discussed.

  19. Mobile fission and activation products in nuclear waste disposal

    NASA Astrophysics Data System (ADS)

    Grambow, Bernd

    2008-12-01

    When disposing nuclear waste in clay formations it is expected that the most radiotoxic elements like Pu, Np or Am move only a few centimetres to meters before they decay. Only a few radionuclides are able to reach the biosphere and contribute to their long-term exposure risks, mainly anionic species like I129, Cl36, Se79 and in some cases C14 and Tc99, whatever the scenario considered. The recent OECD/NEA cosponsored international MOFAP workshop focussed on transport and chemical behaviour of these less toxic radionuclides. New research themes have been addressed, such as how to make use of molecular level information for the understanding of the problem of migration at large distances. Diffusion studies need to face mineralogical heterogeneities over tens to hundreds of meters. Diffusion rates are very low since the clay rock pores are so small (few nm) that electrostatic repulsion limits the space available for anion diffusion (anion exclusion). The large volume of traversed rock will provide so many retention sites that despite weak retention, even certain of these "mobile" nuclides may show significant retardation. However, the question how to measure reliably very low retention parameters has been posed. An important issue is whether redox states or organic/inorganic speciation change from their initial state at the moment of release from the waste during long term contact with surfaces, hydrogen saturated environments, etc.

  20. Mobile fission and activation products in nuclear waste disposal.

    PubMed

    Grambow, Bernd

    2008-12-12

    When disposing nuclear waste in clay formations it is expected that the most radiotoxic elements like Pu, Np or Am move only a few centimetres to meters before they decay. Only a few radionuclides are able to reach the biosphere and contribute to their long-term exposure risks, mainly anionic species like I129, Cl36, Se79 and in some cases C14 and Tc99, whatever the scenario considered. The recent OECD/NEA cosponsored international MOFAP workshop focussed on transport and chemical behaviour of these less toxic radionuclides. New research themes have been addressed, such as how to make use of molecular level information for the understanding of the problem of migration at large distances. Diffusion studies need to face mineralogical heterogeneities over tens to hundreds of meters. Diffusion rates are very low since the clay rock pores are so small (few nm) that electrostatic repulsion limits the space available for anion diffusion (anion exclusion). The large volume of traversed rock will provide so many retention sites that despite weak retention, even certain of these "mobile" nuclides may show significant retardation. However, the question how to measure reliably very low retention parameters has been posed. An important issue is whether redox states or organic/inorganic speciation change from their initial state at the moment of release from the waste during long term contact with surfaces, hydrogen saturated environments, etc.

  1. Electrophoretic dynamics of self-assembling branched DNA structures

    NASA Astrophysics Data System (ADS)

    Heuer, Daniel Milton

    This study advances our understanding of the electrophoretic dynamics of branched biopolymers and explores technologies designed to exploit their unique properties. New self-assembly techniques were developed to create branched DNA for visualization via fluorescence microscopy. Experiments in fixed gel networks reveal a distinct trapping behavior, in contrast with linear topologies. The finding that detection can be achieved by introducing a branch point contributes significantly to the field of separation science and can be exploited to develop new applications. Results obtained in polymer solutions point to identical mobilities for branched and linear topologies, despite large differences in their dynamics. This finding led to a new description of electrophoresis based on non-Newtonian viscoelastic effects in the electric double layer surrounding a charged object. This new theoretical framework presents a new outlook important not only to the electrophoretic physics of nucleic acids, but all charged objects including proteins, colloids, and nanoparticles. To study the behavior of smaller biopolymers, such as restriction fragments and recombination intermediates, a library of symmetrically branched DNA was synthesized followed by characterization in gels. The experimental results contribute a large body of information relating molecular architecture and the dynamics of rigid structures in an electric field. The findings allow us to create new separation technologies based on topology. These contributions can also be utilized in a number of different applications including the study of recombination intermediates and the separation of proteins according to structure. To demonstrate the importance of these findings, a sequence and mutation detection technique was envisioned and applied for genetic analysis. Restriction fragments from mutation "hotspots" in the p53 tumor suppressor gene, known to play a role in cancer development, were analyzed with this technique

  2. All solution processed organic thin film transistor-backplane with printing technology for electrophoretic display

    USGS Publications Warehouse

    Lee, Myung W.; Song, C.K.

    2012-01-01

    In this study, solution processes were developed for backplane using an organic thin film transistor (OTFT) as a driving device for an electrophoretic display (EPD) panel. The processes covered not only the key device of OTFTs but also interlayer and pixel electrodes. The various materials and printing processes were adopted to achieve the requirements of devices and functioning layers. The performance of OTFT of the backplane was sufficient to drive EPD sheet by producing a mobility of 0.12 cm2/v x sec and on/off current ratio of 10(5).

  3. Results of mobile gamma scanning activities in St. Louis, Missouri

    SciTech Connect

    Rodriguez, R E; Witt, D A; Cottrell, W D; Carrier, R F

    1991-06-01

    From 1942 through approximately 1966, the Mallinckrodt Chemical Works operated four plants in St. Louis, Missouri, for the Manhattan Engineer District and the Atomic Energy Commission. A variety of production processes using uranium- and radium-bearing ore materials were performed at the plants. It is the policy of the DOE to verify that radiological conditions at such sites or facilities comply with current DOE guidelines. Guidelines for release and use of such sites have become more stringent as research has provided more information since previous cleanups. The Formerly Utilized Sites Remedial Action Program (FUSRAP) was established as part of that effort to confirm the closeout status of facilities under contract to agencies preceding DOE during early nuclear energy development. Under the FUSRAP program, the Mallinckrodt properties have been previously investigated to determine the extent of on-site radiological contamination. At the request of DOE, Oak Ridge National Laboratory (ORNL) conducted a survey in May 1990, of public roadways and suspected haul routes between the Mallinckrodt plant and storage sites in St. Louis to ensure that no residual radioactive materials were conveyed off-site. A mobile gamma scanning van with an on-board computer system was used to identify possible anomalies. Suspect areas are those displaying measurements deviating from gamma exposure rates identified as typical for radiologically unenhanced areas in the vicinity of the areas of interest. The instrumentation highlighted three anomaly locations each of which measured less than 1m{sup 2} in size. None of the slightly elevated radiation levels originated from material associated with former AEC-related processing operations in the area. The anomalies resulted from elevated concentrations of radionuclides present in phosphate fertilizers, increased thorium in road-base gravel, and emanations from the radioactive storage site near the Latty Avenue airport. 9 refs., 3 figs.

  4. Human movement activity classification approaches that use wearable sensors and mobile devices

    NASA Astrophysics Data System (ADS)

    Kaghyan, Sahak; Sarukhanyan, Hakob; Akopian, David

    2013-03-01

    Cell phones and other mobile devices become part of human culture and change activity and lifestyle patterns. Mobile phone technology continuously evolves and incorporates more and more sensors for enabling advanced applications. Latest generations of smart phones incorporate GPS and WLAN location finding modules, vision cameras, microphones, accelerometers, temperature sensors etc. The availability of these sensors in mass-market communication devices creates exciting new opportunities for data mining applications. Particularly healthcare applications exploiting build-in sensors are very promising. This paper reviews different approaches of human activity recognition.

  5. The dendritic cell cytoskeleton promotes T cell adhesion and activation by constraining ICAM-1 mobility

    PubMed Central

    Comrie, William A.; Li, Shuixing; Boyle, Sarah

    2015-01-01

    Integrity of the dendritic cell (DC) actin cytoskeleton is essential for T cell priming, but the underlying mechanisms are poorly understood. We show that the DC F-actin network regulates the lateral mobility of intracellular cell adhesion molecule 1 (ICAM-1), but not MHCII. ICAM-1 mobility and clustering are regulated by maturation-induced changes in the expression and activation of moesin and α-actinin-1, which associate with actin filaments and the ICAM-1 cytoplasmic domain. Constrained ICAM-1 mobility is important for DC function, as DCs expressing a high-mobility ICAM-1 mutant lacking the cytoplasmic domain exhibit diminished antigen-dependent conjugate formation and T cell priming. These defects are associated with inefficient induction of leukocyte functional antigen 1 (LFA-1) affinity maturation, which is consistent with a model in which constrained ICAM-1 mobility opposes forces on LFA-1 exerted by the T cell cytoskeleton, whereas ICAM-1 clustering enhances valency and further promotes ligand-dependent LFA-1 activation. Our results reveal an important new mechanism through which the DC cytoskeleton regulates receptor activation at the immunological synapse. PMID:25666808

  6. [Electrophoretic study of liver histones in the postnatal ontogeny of white rats: the effect of testosterone propionate and gonadectomy].

    PubMed

    Klimenko, A I; Khints, R

    1976-01-01

    By means of polyacrylamide gel disc electrophoresis heterogeneity, electrophoretic mobility and relative content of different fractions of histones in nuclei of liver cells were studied in gonadectomized Wistar rats and in castrated in intact animals, administered with testosteone propionate. In all the experiments a significant conservatism of histone proteins was found in postnatal development. In animals, treated with the endocrine preparations, the age peculiarities were shown to reflect the quanitative proportion of different histone fractions. PMID:1027242

  7. A Conceptual Framework Based on Activity Theory for Mobile CSCL

    ERIC Educational Resources Information Center

    Zurita, Gustavo; Nussbaum, Miguel

    2007-01-01

    There is a need for collaborative group activities that promote student social interaction in the classroom. Handheld computers interconnected by a wireless network allow people who work on a common task to interact face to face while maintaining the mediation afforded by a technology-based system. Wirelessly interconnected handhelds open up new…

  8. Cell and Particle Interactions and Aggregation During Electrophoretic Motion

    NASA Technical Reports Server (NTRS)

    Wang, Hua; Zeng, Shulin; Loewenberg, Michael; Todd, Paul; Davis, Robert H.

    1996-01-01

    The stability and pairwise aggregation rates of small spherical particles under the collective effects of buoyancy-driven motion and electrophoretic migration are analyzed. The particles are assumed to be non-Brownian, with thin double-layers and different zeta potentials. The particle aggregation rates may be enhanced or reduced, respectively, by parallel and antiparallel alignments of the buoyancy-driven and electrophoretic velocities. For antiparallel alignments, with the buoyancy-driven relative velocity exceeding the electrophoretic relative velocity between two widely-separated particles, there is a 'collision-forbidden region' in parameter space due to hydrodynamic interactions; thus, the suspension becomes stable against aggregation.

  9. Metabolic Cost of Daily Activities and Effect of Mobility Impairment in Older Adults

    PubMed Central

    Knaggs, Jeffrey D; Larkin, Kelly A; Manini, Todd M

    2013-01-01

    OBJECTIVES There is a shortage of information on metabolic costs of daily physical activities in older adults and the effect of having mobility impairments. The primary purpose of this study was to evaluate metabolic equivalent (MET) values on common daily tasks in men and women aged > 70 years compared to normative criteria. A secondary purpose was to determine the effect of having mobility impairments. DESIGN Cross-sectional observational study. SETTING University based research clinic PARTICIPANTS Forty-five participants aged 70 to 90 years of age (mean: 76.3 ± 5.1) volunteered to complete 17 daily activities, each lasting 10 minutes. MEASUREMENTS Oxygen consumption (VO2 = ml•kg−1•min−1) was measured through a mask by a portable gas analyzer and MET values were calculated as measured VO2/3.5 ml•kg−1•min−1. Values were compared to both normative values and between participants with and without mobility impairments. RESULTS Compared to the established normative criteria, measured METs were different in 14 of 17 tasks performed. Compared to measured METs, normative values underestimated walking leisurely (0.87 ± 0.12 METs) walking briskly (0.87 ± 0.12 METs ), and bed making (1.07 ± 0.10 METs ), but overestimated gardening (1.46 ± 0.12 METs) and climbing stairs (0.73 ± 0.18). Participants with impairments had significantly lower METs while gardening, vacuuming/sweeping, stair climbing, and walking briskly. However, when METs were adjusted for performance speed the metabolic costs were 16–27% higher for those with mobility impairments. CONCLUSION Compared to normative values, metabolic costs of daily activities are substantially different in older adults and having mobility impairments increases this metabolic cost. These results may have implications for practitioners to appropriately prescribe daily physical activities for healthy and mobility impaired older adults. PMID:22091979

  10. Persuasive Technology in Mobile Applications Promoting Physical Activity: a Systematic Review.

    PubMed

    Matthews, John; Win, Khin Than; Oinas-Kukkonen, Harri; Freeman, Mark

    2016-03-01

    Persuasive technology in mobile applications can be used to influence the behaviour of users. A framework known as the Persuasive Systems Design model has been developed for designing and evaluating systems that influence the attitudes or behaviours of users. This paper reviews the current state of mobile applications for health behavioural change with an emphasis on applications that promote physical activity. The inbuilt persuasive features of mobile applications were evaluated using the Persuasive Systems Design model. A database search was conducted to identify relevant articles. Articles were then reviewed using the Persuasive Systems Design model as a framework for analysis. Primary task support, dialogue support, and social support were found to be moderately represented in the selected articles. However, system credibility support was found to have only low levels of representation as a persuasive systems design feature in mobile applications for supporting physical activity. To ensure that available mobile technology resources are best used to improve the wellbeing of people, it is important that the design principles that influence the effectiveness of persuasive technology be understood. PMID:26748792

  11. Persuasive Technology in Mobile Applications Promoting Physical Activity: a Systematic Review.

    PubMed

    Matthews, John; Win, Khin Than; Oinas-Kukkonen, Harri; Freeman, Mark

    2016-03-01

    Persuasive technology in mobile applications can be used to influence the behaviour of users. A framework known as the Persuasive Systems Design model has been developed for designing and evaluating systems that influence the attitudes or behaviours of users. This paper reviews the current state of mobile applications for health behavioural change with an emphasis on applications that promote physical activity. The inbuilt persuasive features of mobile applications were evaluated using the Persuasive Systems Design model. A database search was conducted to identify relevant articles. Articles were then reviewed using the Persuasive Systems Design model as a framework for analysis. Primary task support, dialogue support, and social support were found to be moderately represented in the selected articles. However, system credibility support was found to have only low levels of representation as a persuasive systems design feature in mobile applications for supporting physical activity. To ensure that available mobile technology resources are best used to improve the wellbeing of people, it is important that the design principles that influence the effectiveness of persuasive technology be understood.

  12. Preparation and application of microcapsule-encapsulated color electrophortic fluid in Isopar M system for electrophoretic display

    NASA Astrophysics Data System (ADS)

    Sun, Cui; Feng, Ya-Qing; Zhang, Bao; Li, Xiang-Gao; Shao, Ji-Zhou; Han, Jing-Jing; Chen, Xu

    2013-05-01

    The use of Isopar M as a liquid suspending fluid for electrophoretic display was studied. The dispersion stability and chargeability of pigments suspended in Isopar M were investigated. Polyisobutylene monosuccinimide (T-151) as the charge control additive in Isopar M electrophoretic fluid can provide a good electrophoretic mobility to the particles. The wall materials of a series of blue-white, red-white and yellow-white dual-particle microcapsules were prepared by in situ polymerization of urea and formaldehyde. The mass ratio of wall/core material was a key factor in influencing the yield of microcapsules. The concentration of resorcinol has an impact on the surface morphology and mechanical strength of microcapsule wall. Microcapsules' surface morphologies were characterized by optical microscopy and scanning electron microscopy. The performance of the microcapsules with different binder materials and adhesive layers were investigated. Contrast ratio of microcapsules display device were tested every 10 days for a period of 90 days. The compatibility of Isopar M with both the electrophoretic particles and bounding capsule was studied.

  13. Training Learners to Use Quizlet Vocabulary Activities on Mobile Phones in Vietnam with Facebook

    ERIC Educational Resources Information Center

    Tran, Phuong

    2016-01-01

    Mobile phone ownership among university students in Vietnam has reached almost 100%, exceeding that of Internet-capable desktop computers. This has made them increasingly popular to allow learners to carry out learning activities outside of the classroom, but some studies have suggested that learners are not always willing to engage in activities…

  14. Outdoor Built Environment Barriers and Facilitators to Activity among Midlife and Older Adults with Mobility Disabilities

    ERIC Educational Resources Information Center

    Rosenberg, Dori E.; Huang, Deborah L.; Simonovich, Shannon D.; Belza, Basia

    2013-01-01

    Purpose: To gain better understanding of how the built environment impacts neighborhood-based physical activity among midlife and older adults with mobility disabilities. Design and methods: We conducted in-depth interviews with 35 adults over age 50, which used an assistive device and lived in King County, Washington, U.S. In addition,…

  15. Molecular analysis and physicochemical properties of electrophoretic variants of wild soybean Glycine soja storage proteins.

    PubMed

    Fukuda, Takako; Maruyama, Nobuyuki; Kanazawa, Akira; Abe, Jun; Shimamoto, Yoshiya; Hiemori, Miki; Tsuji, Hideaki; Tanisaka, Takatoshi; Utsumi, Shigeru

    2005-05-01

    Cultivated soybeans (Glycine max) are derived from wild soybeans (Glycine soja) and can be crossed with them to produce fertile offspring. The latter exhibit greater genetic variation than the former, suggesting a possibility that wild soybeans contain storage proteins with properties different from and better than those of cultivated soybeans. To identify a wild soybean suitable for breeding a new soybean cultivar, we analyzed seed proteins from 390 lines of wild soybeans by electrophoresis. We found some lines containing electrophoretic variants of glycinin and beta-conglycinin subunits: one line containing a small alpha' subunit of beta-conglycinin and two and five lines containing small A3 and large A4 polypeptides of glycinin, respectively. Beta-Conglycinin and glycinin containing such variant subunits exhibited solubility and emulsifying ability similar to those of the predominant types of wild and cultivated soybeans. Glycinins containing small A3 and large A4 gave a shoulder derived from the start of denaturation at a temperature 4 degrees C lower than that of glycinin from the predominant types of wild and cultivated soybeans, although their thermal denaturation midpoint temperatures were very similar to each other. Cloning and sequencing of the predominant and variant subunit cDNAs revealed that the small alpha' and the small A3 lacked 24 amino acid residues in the extension region and four amino acid residues in the hypervariable region, respectively, and that the large A4 did not have an insert corresponding to the difference in the electrophoretic mobility but Arg279 and Gln305 were replaced by glutamine and histidine, respectively, in the hypervariable region. These suggest that small differences even in the hypervariable region can affect the thermal stability, as well as the electrophoretic mobilities, of the proteins.

  16. Calcium can mobilize and activate myosin-VI

    PubMed Central

    Batters, Christopher; Brack, Dario; Ellrich, Heike; Averbeck, Beate; Veigel, Claudia

    2016-01-01

    The ability to coordinate the timing of motor protein activation lies at the center of a wide range of cellular motile processes including endocytosis, cell division, and cancer cell migration. We show that calcium dramatically alters the conformation and activity of the myosin-VI motor implicated in pivotal steps of these processes. We resolved the change in motor conformation and in structural flexibility using single particle analysis of electron microscopic data and identified interacting domains using fluorescence spectroscopy. We discovered that calcium binding to calmodulin increases the binding affinity by a factor of 2,500 for a bipartite binding site on myosin-VI. The ability of calcium-calmodulin to seek out and bridge between binding site components directs a major rearrangement of the motor from a compact dormant state into a cargo binding primed state that is nonmotile. The lack of motility at high calcium is due to calmodulin switching to a higher affinity binding site, which leaves the original IQ-motif exposed, thereby destabilizing the lever arm. The return to low calcium can either restabilize the lever arm, required for translocating the cargo-bound motors toward the center of the cell, or refold the cargo-free motors into an inactive state ready for the next cellular calcium flux. PMID:26811464

  17. Electrophoretic transfer of proteins across polyacrylamide membranes.

    PubMed

    Rylatt, D B; Napoli, M; Ogle, D; Gilbert, A; Lim, S; Nair, C H

    1999-12-31

    The electrophoretic transfer of purified proteins has been examined in a Gradiflow "Babyflow BF100" unit. A number of factors affect protein separation within this preparative electrophoresis system. We established that the rate of protein transfer was proportional to the applied voltage. The transfer is slowest at the isoelectric point (pI) and increased the further away the pH was from the pI of the protein. Protein transfer was found to be independent of the ionic strength of the buffer, for buffers that excluded the addition of strong acids or strong bases or sodium chloride. Transfer decreased as the pore size of the membrane decreased. Finally, transfer was inhibited at high salt concentrations in the protein solution, but remained unaffected when urea and non-ionic detergents were added to the solution. To increase the speed of protein separations, buffers with low conductivity should be used. A pH for the optimal separation should be selected on the basis of the relative pI and size of the target proteins and that of the major contaminants. PMID:10674937

  18. Microencapsulated Electrophoretic Films for Electronic Paper Displays

    NASA Astrophysics Data System (ADS)

    Amundson, Karl

    2003-03-01

    Despite the dominance of liquid crystal displays, they do not perform some functions very well. While backlit liquid crystal displays can offer excellent color performance, they wash out in bright lighting and suffer from high power consumption. Reflective liquid crystal displays have limited brightness, making these devices challenging to read for long periods of time. Flexible liquid crystal displays are difficult to manufacture and keep stable. All of these attributes (long battery lifetime, bright reflective appearance, compatibility with flexible substrates) are traits that would be found in an ideal electronic paper display - an updateable substitute for paper that could be employed in electronic books, newspapers, and other applications. I will discuss technologies that are being developed for electronic-paper-like displays, and especially on particle-based technologies. A microencapsulated electrophoretic display technology is being developed at the E Ink corporation. This display film offers offer high brightness and an ink-on-paper appearance, compatibility with flexible substrates, and image stability that can lead to very low power consumption. I will present some of the physical and chemical challenges associated with making display films with high performance.

  19. Tubulin evolution: an electrophoretic and immunological analysis.

    PubMed

    Adoutte, A; Claisse, M; Cance, J

    1984-03-01

    This paper summarizes a survey of the electrophoretic behavior of the tubulins of 23 species (mostly protists) as well as their reactivity towards 4 anti-tubulin antibodies (raised against two ciliate tubulins and two vertebrate ones). Some generalizations concerning the relative migration rates of alpha VS beta tubulin could be made, in particular the alpha/beta inversion, first described in Physarum was extended to several ciliates. Antivertebrate tubulin antibodies displayed a very broad spectrum of reactions, reacting with virtually all the species tested. They appear to correspond to auto-antibodies no exclusively directed against species specific determinants. In contrast, the two anti-ciliate tubulin antibodies displayed a narrow species specificity reacting only with a limited subset of protists. They were shown to be specific for a small number of immunological determinants present on ciliate tubulins. This allowed a rough evaluation of evolutionary relatedness between the various groups of protists analyzed. The results are discussed within the framework of a number of published phyllogenies and shown to be in striking agreement with some of the schemes.

  20. Capillary electrophoretic behavior of seven sulfonylureas.

    PubMed

    Matchett, W H; Winnik, W; Brumley, W C

    1996-01-01

    The electrophoretic behavior of seven sulfonylureas (bensulfuron methyl, sulfometuron methyl, nicosulfuron [accent], chlorimuron ethyl, thifensulfuron methyl [harmony], metsulfuron methyl, and chlorsulfuron) was studied under capillary zone electrophoresis (CZE) and micellar electrokinetic chromatography (MEKC) conditions. Mixtures of these compounds were separated with very high efficiencies (2 x 10(5) theoretical plates) in a running buffer consisting of 3 parts acetate buffer (25 mM, pH 5.0) and 1 part acetonitrile. In this buffer system, acetonitrile was shown to be superior to methanol, acetone, and ethanol as a nonpolar additive, but any of these solvents can be used to reduce electroosmotic flow (EOF) and to obtain adequate separation. On-column detection limits at 214 nM were of the order of 80-100 fM. Micellar agents such as sodium dodecyl sulfate (SDS) and sodium cholate (but not monosialoganglioside-Gm1 or starburst dendrimer, generation 2.5) improved separation in phosphate and borate buffers. Implications of these results for the development of methods to detect these compounds on matrices of environmental origin are discussed. In particular, the instability of these compounds in methanol is noted and degradation products are detected using free zone CE. The methanolysis products of sulfometuron are tentatively identified by tandem MS (negative ion conditions) as 2-amino-4,6-dimethylpyrimidine and 2-carboxymethylbenz(N-carboxymethyl)sulfonamide.

  1. Electrophoretic forming of functionally-graded materials

    SciTech Connect

    Sarkar, P.; Datta, S.; Nicholson, P.S.

    1997-12-31

    Electrophoretic deposition (EPD) is a colloidal forming process where electrically charged particles are deposited onto an oppositely-charged electrode from an electrostatically stabilized suspension by the application of a dc electric field. It is a cheap and facile technique to fabricate complicated ceramic shapes. EPD is very effective method to synthesize ceramic/ceramic and metal/ceramic composites, eg.; dispersed, laminar, fibre reinforced, and functionally graded materials (FGM) etc. By EPD it is possible to synthesize step FGMs and continuous profile FGMs. The compositional profile of the FGM can be controlled by deposition current density, second component flow rate, suspension concentration etc. Step and continuous profile Al{sub 2}O{sub 3}/YSZ and continuous profile Al{sub 2}O{sub 3}/MoSi{sub 2}, Al{sub 2}O{sub 3}/Ni and YSZ/Ni fabrication is reported herein. The microstructures of the FGMs produced were characterized by optical/electron microscopy and micro-indentation was used to quantify the Vicker`s hardness and fracture toughness variation across The FGM sections.

  2. Fluid Delivery System For Capillary Electrophoretic Applications.

    DOEpatents

    Li, Qingbo; Liu, Changsheng; Kane, Thomas E.; Kernan, John R.; Sonnenschein, Bernard; Sharer, Michael V.

    2002-04-23

    An automated electrophoretic system is disclosed. The system employs a capillary cartridge having a plurality of capillary tubes. The cartridge has a first array of capillary ends projecting from one side of a plate. The first array of capillary ends are spaced apart in substantially the same manner as the wells of a microtitre tray of standard size. This allows one to simultaneously perform capillary electrophoresis on samples present in each of the wells of the tray. The system includes a stacked, dual carrousel arrangement to eliminate cross-contamination resulting from reuse of the same buffer tray on consecutive executions from electrophoresis. The system also has a gel delivery module containing a gel syringe/a stepper motor or a high pressure chamber with a pump to quickly and uniformly deliver gel through the capillary tubes. The system further includes a multi-wavelength beam generator to generate a laser beam which produces a beam with a wide range of wavelengths. An off-line capillary reconditioner thoroughly cleans a capillary cartridge to enable simultaneous execution of electrophoresis with another capillary cartridge. The streamlined nature of the off-line capillary reconditioner offers the advantage of increased system throughput with a minimal increase in system cost.

  3. Cell and Particle Interactions and Aggregation During Electrophoretic Motion

    NASA Technical Reports Server (NTRS)

    Davis, Robert H.

    2000-01-01

    The objectives of this research were (i) to perform experiments for observing and quantifying electrophoretic aggregation, (ii) to develop a theoretical description to appropriately analyze and compare with the experimental results, (iii) to study the combined effects of electrophoretic and gravitational aggregation of large particles, and the combined effects of electrophoretic and Brownian aggregation of small particles, and (iv) to perform a preliminary design of a potential future flight experiment involving electrophoretic aggregation. Electrophoresis refers to the motion of charged particles, droplets or molecules in response to an applied electric field. Electrophoresis is commonly used for analysis and separation of biological particles or molecules. When particles have different surface charge densities or potentials, they will migrate at different velocities in an electric field. This differential migration leads to the possibility that they will collide and aggregate, thereby preventing separation.

  4. Carboxylated ficolls: preparation, characterization, and electrophoretic behavior of model charged nanospheres.

    PubMed

    Guo, Xuhong; Kirton, Gavin F; Dubin, Paul L

    2006-10-26

    Carboxylated ficolls were prepared as model spherical colloids of variable charge and size, with radii ranging from 3.0 to 19.3 nm. Capillary electrophoresis (CE), electrophoretic light scattering (ELS), and potentiometric titration were used to determine mobilities as a function of pH, degree of ionization alpha, and surface potential psi(0). Measured mobilities typically display a plateau at high pH, corresponding to high alpha and psi(0), confirming the general nature of this effect for charged spheres, seen also for charged dendrimers and charged latex particles. This result is examined in the context of a discontinuity in mobility predicted by the Wiersema, O'Brien, and White (WOW) theory and a more recent primitive model electrophoresis (PME) theory, in which bound counterions are considered either as point charges or as hard spheres. While no mobility maximum can be determined as expected by these two theories, our data seem more to support Belloni's theoretical expectations on charged polymers and spheres. Here we explain the mobility plateaus in terms of counterions accumulated close to the surface (surface potential-determining ions) or within the shear plane (mobility-determining ions).

  5. Enhanced electrophoretic motion using supercapacitor-based energy storage system.

    PubMed

    Liu, Ran; Wong, Flory; Duan, Wentao; Sen, Ayusman

    2013-12-23

    Electrophoretic motion at low potentials is facilitated by redox chemistry occurring in a supercapacitor-based electrochemical energy storage system during charge and discharge. We show that MnO2 -modified electrodes can effectively alleviate the electrode surface polarization, the main factor that leads to inefficient electrophoresis at low voltages. A self-powered electrophoretic system based on a discharging battery has been also fabricated.

  6. Monodisperse light color nanoparticle ink toward chromatic electrophoretic displays.

    PubMed

    Peng, Bo; Li, Yue; Li, Jian; Bi, Lei; Lu, Haipeng; Xie, Jianliang; Ren, Xiangling; Cao, Yonghai; Wang, Ning; Meng, Xianwei; Deng, Longjiang; Guo, Zhanhu

    2016-06-01

    The facile synthesis of nanoparticles for precise image control and fast response of chromatic electrophoretic displays (EPDs) is a challenge. Herein, we report a general method to prepare pink, blue, and yellow nanoparticles with low density and a tunable size of 230-310 nm. The monodispersity is down to 0.02 and surface charges are up to 666e. Importantly, our work highlights the feasibility of chromatic nanoparticles as cost-effective candidates for electrophoretic displays. PMID:27189743

  7. Thermal tracking in mobile robots for leak inspection activities.

    PubMed

    Ibarguren, Aitor; Molina, Jorge; Susperregi, Loreto; Maurtua, Iñaki

    2013-10-09

    Maintenance tasks are crucial for all kind of industries, especially in extensive industrial plants, like solar thermal power plants. The incorporation of robots is a key issue for automating inspection activities, as it will allow a constant and regular control over the whole plant. This paper presents an autonomous robotic system to perform pipeline inspection for early detection and prevention of leakages in thermal power plants, based on the work developed within the MAINBOT (http://www.mainbot.eu) European project. Based on the information provided by a thermographic camera, the system is able to detect leakages in the collectors and pipelines. Beside the leakage detection algorithms, the system includes a particle filter-based tracking algorithm to keep the target in the field of view of the camera and to avoid the irregularities of the terrain while the robot patrols the plant. The information provided by the particle filter is further used to command a robot arm, which handles the camera and ensures that the target is always within the image. The obtained results show the suitability of the proposed approach, adding a tracking algorithm to improve the performance of the leakage detection system.

  8. Thermal Tracking in Mobile Robots for Leak Inspection Activities

    PubMed Central

    Ibarguren, Aitor; Molina, Jorge; Susperregi, Loreto; Maurtua, Iñaki

    2013-01-01

    Maintenance tasks are crucial for all kind of industries, especially in extensive industrial plants, like solar thermal power plants. The incorporation of robots is a key issue for automating inspection activities, as it will allow a constant and regular control over the whole plant. This paper presents an autonomous robotic system to perform pipeline inspection for early detection and prevention of leakages in thermal power plants, based on the work developed within the MAINBOT (http://www.mainbot.eu) European project. Based on the information provided by a thermographic camera, the system is able to detect leakages in the collectors and pipelines. Beside the leakage detection algorithms, the system includes a particle filter-based tracking algorithm to keep the target in the field of view of the camera and to avoid the irregularities of the terrain while the robot patrols the plant. The information provided by the particle filter is further used to command a robot arm, which handles the camera and ensures that the target is always within the image. The obtained results show the suitability of the proposed approach, adding a tracking algorithm to improve the performance of the leakage detection system. PMID:24113684

  9. Thermal tracking in mobile robots for leak inspection activities.

    PubMed

    Ibarguren, Aitor; Molina, Jorge; Susperregi, Loreto; Maurtua, Iñaki

    2013-01-01

    Maintenance tasks are crucial for all kind of industries, especially in extensive industrial plants, like solar thermal power plants. The incorporation of robots is a key issue for automating inspection activities, as it will allow a constant and regular control over the whole plant. This paper presents an autonomous robotic system to perform pipeline inspection for early detection and prevention of leakages in thermal power plants, based on the work developed within the MAINBOT (http://www.mainbot.eu) European project. Based on the information provided by a thermographic camera, the system is able to detect leakages in the collectors and pipelines. Beside the leakage detection algorithms, the system includes a particle filter-based tracking algorithm to keep the target in the field of view of the camera and to avoid the irregularities of the terrain while the robot patrols the plant. The information provided by the particle filter is further used to command a robot arm, which handles the camera and ensures that the target is always within the image. The obtained results show the suitability of the proposed approach, adding a tracking algorithm to improve the performance of the leakage detection system. PMID:24113684

  10. Glucose-6-phosphate dehydrogenase from Plasmodium berghei: kinetic and electrophoretic characterization.

    PubMed

    Buckwitz, D; Jacobasch, G; Kuckelkorn, U; Plonka, A; Gerth, C

    1990-04-01

    Evidence is given for the existence of a parasite-specific glucose-6-phosphate dehydrogenase (G6PD) in Plasmodium berghei by characterization of its kinetic and electrophoretic properties. From infected rat erythrocytes the parasites were isolated, washed, and lysed. G6PD was purified by affinity chromatography with 2'5'-ADP-Sepharose 4B, although the separation of the malaria-specific enzyme from that of the host cell was not complete. Malarial G6PD significantly differed from the red cell enzyme with respect to its electrophoretic properties. In cellulose acetate electrophoresis, a band with catodic mobility was observed in addition to the anodically mobile host cell enzyme at pH 7.0. The subunits of the parasite-specific G6PD have a molecular weight of 55 kDa in contrast to 59 kDa of red cell G6PD subunits. The enzyme from P. berghei shows no cross-reactivity with polyclonal antibodies against G6PD from rat erythrocytes. Thus, a close evolutionary relationship between both proteins and the presence of proteolytic modifications could be excluded. The Km value for G6P of malarial G6PD is increased by one order of magnitude compared with the host cell enzyme.

  11. Origin of the effective mobility in non-linear active micro-rheology

    NASA Astrophysics Data System (ADS)

    Santamaría-Holek, I.; Pérez-Madrid, A.

    2016-10-01

    The distinction between the damping coefficient and the effective non-linear mobility of driven particles in active micro-rheology of supercooled liquids is explained in terms of individual and collective dynamics. The effective mobility arises as a collective effect which gives insight into the energy landscape of the system. On the other hand, the damping coefficient is a constant that modulates the effect of external forces over the thermal energy which particles have at their disposition to perform Brownian motion. For long times, these thermal fluctuations become characterized in terms of an effective temperature that is a consequence of the dynamic coupling between kinetic and configurational degrees of freedom induced by the presence of the strong external force. The interplay between collective mobility and effective temperature allows to formulate a generalized Stokes-Einstein relation that may be used to determine the collective diffusion coefficient. The explicit relations we deduce reproduce simulation data remarkably well.

  12. Mass Spectrometric Collisional Activation and Product Ion Mobility of Human Serum Neutral Lipid Extracts

    PubMed Central

    Hankin, Joseph A.; Barkley, Robert M.; Zemski-Berry, Karin; Deng, Yiming; Murphy, Robert C.

    2016-01-01

    A novel method for lipid analysis called CTS (collisional activation and traveling wave mass spectrometry) involving tandem mass spectrometry of all precursor ions with ion mobility determinations of all product ions was applied to a sample of human serum. The resulting four dimensional data set (precursor ion, product ion, ion mobility values, and intensity) was found to be useful for characterization of lipids as classes as well as identification of specific species. Utilization of ion mobility measurements of the product ions is a novel approach for lipid analysis. The trends and patterns of product mobility values when visually displayed yield information on lipid classes and specific species independent of mass determination. The collection of a comprehensive set of data that incorporates all precursor-product relationships combined with ion mobility measurements of all products enables data analysis where different molecular properties can be juxtaposed and analyzed to assist with class and species identification. Overall, CTS is powerful, specific, and comprehensive method for lipid analysis. PMID:27213895

  13. The experience of choice in physical activity contexts for adults with mobility impairments.

    PubMed

    Morphy, Lorraine Y; Goodwin, Donna

    2012-04-01

    This exploratory study described the experiences of choice in physical activity contexts for adults with mobility impairments. The experiences of 3 female and 2 males with mobility impairments between 18 and 23 years of age were described using the interpretive phenomenological methods of individual interviews, written stories, and field notes. Thematic analysis revealed three themes: (a) interpreting the setting described participants' interpretation of the environment, person, and task when making movement choices; (b) alternative selection described how participants actively engaged in analyzing alternatives and choosing among them; and (c) implications of choices made described participants' evaluations of good and bad choices and what was learned. Evidence of effective choice making among adults with physical impairments suggests the potential efficacy of ecological task analysis as a pedagogical tool in physical activity contexts.

  14. Mobile phone electromagnetic radiation activates MAPK signaling and regulates viability in Drosophila.

    PubMed

    Lee, Kyu-Sun; Choi, Jong-Soon; Hong, Sae-Yong; Son, Tae-Ho; Yu, Kweon

    2008-07-01

    Mobile phones are widely used in the modern world. However, biological effects of electromagnetic radiation produced by mobile phones are largely unknown. In this report, we show biological effects of the mobile phone 835 MHz electromagnetic field (EMF) in the Drosophila model system. When flies were exposed to the specific absorption rate (SAR) 1.6 W/kg, which is the proposed exposure limit by the American National Standards Institute (ANSI), more than 90% of the flies were viable even after the 30 h exposure. However, in the SAR 4.0 W/kg strong EMF exposure, viability dropped from the 12 h exposure. These EMF exposures triggered stress response and increased the production of reactive oxygen species. The EMF exposures also activated extracellular signal regulated kinase (ERK) and c-Jun N-terminal kinase (JNK) signaling, but not p38 kinase signaling. Interestingly, SAR 1.6 W/kg activated mainly ERK signaling and expression of an anti-apoptotic gene, whereas SAR 4.0 W/kg strongly activated JNK signaling and expression of apoptotic genes. In addition, SAR 4.0 W/kg amplified the number of apoptotic cells in the fly brain. These findings demonstrate that the exposure limit on electromagnetic radiation proposed by ANSI triggered ERK-survival signaling but the strong electromagnetic radiation activated JNK-apoptotic signaling in Drosophila.

  15. Metabolic and cytoskeletal modulation of transferrin receptor mobility in mitogen-activated human lymphocytes.

    PubMed Central

    Galbraith, G M; Galbraith, R M

    1980-01-01

    The transferrin receptors which appear on mitogen-activated human peripheral blood lymphocytes were found by the use of immunofluorescence techniques to display temperature-dependent patching and capping reactions upon binding of transferrin. Lateral mobility of ligand-occupied membrane sites was accompanied by both shedding and endocytosis of receptor-transferrin complexes. In the presence of sodium azide or the microfilament inhibitor cytochalasin B, cap formation and shedding were markedly inhibited. In contrast, endocytosis of patched receptor-ligand complexes was inhibited by azide and microtubule inhibitors, including colchicine, vinblastine and vincristine. Co-capping experiments performed to elucidate further the alterations in membrane configuration involved in these reactions failed to reveal any topographical relationship between transferrin receptors and lectin-binding sites in these cells. These studied indicate that temperature-dependent mobility of transferrin receptors upon mitogen-activated peripheral blood lymphocytes is dependent upon the integrity of the cytoskeletal system and metabolic function of the cell. PMID:6258830

  16. Multiple Behavior Change in Diet and Activity: A Randomized Controlled Trial Using Mobile Technology

    PubMed Central

    Spring, Bonnie; Schneider, Kristin; McFadden, H.G.; Vaughn, Jocelyn; Kozak, Andrea T.; Smith, Malaina; Moller, Arlen C.; Epstein, Leonard H.; DeMott, Andrew; Hedeker, Donald; Siddique, Juned; Lloyd-Jones, Donald M.

    2012-01-01

    Background Many patients exhibit multiple chronic disease risk behaviors. Research provides little information about advice that can maximize simultaneous health behavior changes. Methods To test which combination of diet and activity advice maximizes healthy change, we randomized 204 adults with elevated saturated fat and low fruit/vegetable intakes, high sedentary leisure time and low physical activity to one of four treatments: increase fruit/vegetable and physical activity; decrease fat and sedentary leisure; decrease fat and increase physical activity; increase fruit/vegetable and decrease sedentary leisure. Treatments provided three weeks of remote coaching supported by mobile decision support technology and financial incentives. During treatment, incentives were contingent on using the mobile device to self-monitor and attain behavioral targets; during follow-up they were contingent only on recording. The outcome was standardized, composite improvement on the four diet and activity behaviors at end of treatment and five month follow-up. Results Of those randomized, 200 (98%) completed follow-up. The increase fruit/vegetable and decrease sedentary leisure treatment improved more than the other 3 treatments (p<.001). Specifically, fruit/vegetables increased from 1.2 servings/day to 5.5; sedentary leisure decreased from 219.2 minutes/day to 89.3; saturated fat decreased from 12.0% of calories consumed to 9.5%. Differences between treatment groups were maintained through follow-up. Traditional dieting (decrease fat and increase physical activity) improved less than the other 3 treatments (p<.001). Conclusions Remote coaching supported by mobile technology and financial incentives holds promise to improve diet and activity. Targeting fruits/vegetables and sedentary leisure together maximizes overall adoption and maintenance of multiple healthy behavior changes. PMID:22636824

  17. The effect of substrate molecular mobility on surface induced immune complement activation and blood plasma coagulation.

    PubMed

    Berglin, Mattias; Andersson, Marcus; Sellborn, Anders; Elwing, Hans

    2004-08-01

    Changing the length of the alkyl ester side chain in poly(alkyl methacrylates) provides a unique opportunity to systematically vary the mobility of the polymer chains, or in other words vary the glass transition temperature (T(g)), without greatly affect the solid surface energy (gamma(s)) of the polymer. A series of poly(alkyl methacrylate) coatings was therefore analysed with regard to the human immune complement (IC) activation and the surface associated blood plasma coagulation cascade (CC) properties. For the IC and CC measurements we used a quartz crystal microbalance (QCM) where we modified the chemistry of the sensor surface by applying 10-30 nm thick poly(alkyl methacrylate) coatings. The surface energy was calculated from water contact angles and small differences between the coatings were observed. The surface chemistry of the coatings, as determined with X-ray photoelectron spectroscopy (XPS), showed no deviation from expected compositions. Tapping mode atomic force microscopy (TM-AFM) measurements revealed that all coatings displayed similar morphology and the roughness was in the range of 0.7-0.9 nm. Increased polymer mobility correlated with a decrease in IC activation, measured as a decreased C3c deposition at the surface. The surface induced CC, measured as fibrin clot formation at the surface, was different between the different coatings but no correlation with molecular mobility was observed. Thus, the molecular mobility of the polymer chains had a major effect on both the IC and the CC and it seems that different aspects of the chemistry of the solid surface regulate activation of the IC and the CC.

  18. Biochemical and electrophoretic studies of erythrocyte pyridoxine kinase in white and black Americans.

    PubMed

    Chern, C J; Beutler, E

    1976-01-01

    The mean PNK activity in red blood cells from black subjects was only about 40% of that in whites. Among 51 whites examined, one was found to have enzyme deficiency. The estimated gene frequencies for PNKH (the common allele in whites which codes for higher enzyme activity) and PNKL (the common allele in blacks which codes for lower enzyme activity) were .35 and .65, respectively, for black donors, and .81 and .19, respectively, for white donors, The variant enzyme in persons with enzyme deficiency was associated with an increased rate of degradation in red cells during aging. No other biochemical or electrophoretic differences were detected.

  19. Using Internet and Mobile Phone Technology to Deliver an Automated Physical Activity Program: Randomized Controlled Trial

    PubMed Central

    Catt, Michael; De Boni, Marco; Fairley, Bruce William; Hurst, Tina; Murray, Peter; Richardson, Alannah; Sodhi, Jaspreet Singh

    2007-01-01

    Background The Internet has potential as a medium for health behavior change programs, but no controlled studies have yet evaluated the impact of a fully automated physical activity intervention over several months with real-time objective feedback from a monitor. Objective The aim was to evaluate the impact of a physical activity program based on the Internet and mobile phone technology provided to individuals for 9 weeks. Methods A single-center, randomized, stratified controlled trial was conducted from September to December 2005 in Bedfordshire, United Kingdom, with 77 healthy adults whose mean age was 40.4 years (SD = 7.6) and mean body mass index was 26.3 (SD = 3.4). Participants were randomized to a test group that had access to an Internet and mobile phone–based physical activity program (n = 47) or to a control group (n = 30) that received no support. The test group received tailored solutions for perceived barriers, a schedule to plan weekly exercise sessions with mobile phone and email reminders, a message board to share their experiences with others, and feedback on their level of physical activity. Both groups were issued a wrist-worn accelerometer to monitor their level of physical activity; only the test group received real-time feedback via the Internet. The main outcome measures were accelerometer data and self-report of physical activity. Results At the end of the study period, the test group reported a significantly greater increase over baseline than did the control group for perceived control (P < .001) and intention/expectation to exercise (P < .001). Intent-to-treat analyses of both the accelerometer data (P = .02) and leisure time self-report data (P = .03) found a higher level of moderate physical activity in the test group. The average increase (over the control group) in accelerometer-measured moderate physical activity was 2 h 18 min per week. The test group also lost more percent body fat than the control group (test group: −2

  20. An active view planning method for mobile robots using a trinocular visual sensor

    NASA Astrophysics Data System (ADS)

    Kim, Min Y.; Cho, Hyungsuck

    2003-10-01

    The ability of mobile robots to perceive and recognize environments is essential for autonomous navigation. To improve the performance of autonomous environment perception for mobile robots, it is important to effectively plan the next pose (position and orientation) of the sensor system at a current navigation state. In this paper, we propose a next-view-planning method for autonomous map construction needed for mobile robots with visual range sensor systems. The proposed view-planning method mimics the decision-making method of human beings, and uses the occlusion information reduced from the geometric relationship between the sensor view and objects as an important clue for the next sensor view planning. The proposed view-planning algorithms are developed in the following steps: 1) Given a prior map and range measurements sensed at a current location of the mobile robot, it is determined which parts in the map are interested in a view of solving the map uncertainty. 2) Based on the selected potential regions, some candidate poses of the sensor system for the next environment sensing are carefully generated. 3) The created candidates are evaluated by using a specially designed evaluation parameter, and the best one of them is selected as a next sensor position based on a fuzzy decision-making method. In this work, the principle of the view planning method is described in detail, and a series of experimental tests is performed to show the feasibility of the method for autonomous map building. For sensing the environments, an active trinocular vision sensor using laser structured light is utilized, which is mounted on the pan-tilt mechanism of the mobile robot, which is composed of a laser stripe projector and two cameras.

  1. A plasmid containing the human metallothionein II gene can function as an antibody-assisted electrophoretic biosensor for heavy metals.

    PubMed

    Wooten, Dennis C; Starr, Clarise R; Lyon, Wanda J

    2016-01-01

    Different forms of heavy metals affect biochemical systems in characteristic ways that cannot be detected with typical metal analysis methods like atomic absorption spectrometry. Further, using living systems to analyze interaction of heavy metals with biochemical systems can be laborious and unreliable. To generate a reliable easy-to-use biologically-based biosensor system, the entire human metallothionein-II (MT-II) gene was incorporated into a plasmid (pUC57-MT) easily replicated in Escherichia coli. In this system, a commercial polyclonal antibody raised against human metal-responsive transcription factor-1 protein (MTF-1 protein) could modify the electrophoretic migration patterns (i.e. cause specific decreases in agarose gel electrophoretic mobility) of the plasmid in the presence or absence of heavy metals other than zinc (Zn). In the study here, heavy metals, MTF-1 protein, and polyclonal anti-MTF-1 antibody were used to assess pUC57-MT plasmid antibody-assisted electrophoretic mobility. Anti-MTF-1 antibody bound both MTF-1 protein and pUC57-MT plasmid in a non-competitive fashion such that it could be used to differentiate specific heavy metal binding. The results showed that antibody-inhibited plasmid migration was heavy metal level-dependent. Zinc caused a unique mobility shift pattern opposite to that of other metals tested, i.e. Zn blocked the antibody ability to inhibit plasmid migration, despite a greatly increased affinity for DNA by the antibody when Zn was present. The Zn effect was reversed/modified by adding MTF-1 protein. Additionally, antibody inhibition of plasmid mobility was resistant to heat pre-treatment and trypsinization, indicating absence of residual DNA extraction-resistant bacterial DNA binding proteins. DNA binding by anti-DNA antibodies may be commonly enhanced by xenobiotic heavy metals and elevated levels of Zn, thus making them potentially effective tools for assessment of heavy metal bioavailability in aqueous solutions and

  2. Electrophoretic interactions and aggregation of colloidal biological particles

    NASA Technical Reports Server (NTRS)

    Davis, Robert H.; Nichols, Scott C.; Loewenberg, Michael; Todd, Paul

    1994-01-01

    The separation of cells or particles from solution has traditionally been accomplished with centrifuges or by sedimentation; however, many particles have specific densities close to unity, making buoyancy-driven motion slow or negligible, but most cells and particles carry surface charges, making them ideal for electrophoretic separation. Both buoyancy-driven and electrophoretic separation may be influenced by hydrodynamic interactions and aggregation of neighboring particles. Aggregation by electrophoresis was analyzed for two non-Brownian particles with different zeta potentials and thin double layers migrating through a viscous fluid. The results indicate that the initial rate of electrophoretically-driven aggregation may exceed that of buoyancy-driven aggregation, even under conditions in which buoyancy-driven relative motion of noninteracting particles is dominant.

  3. A feasibility study of the in vivo prompt gamma activation analysis using a mobile nuclear reactor.

    PubMed

    Chung, C; Yuan, L J; Chen, K B; Weng, P S; Chang, P S; Ho, Y H

    1985-05-01

    A facility for in vivo prompt gamma activation analysis using moderated neutron beams from a 0.1 W mobile nuclear reactor is described. The low-power nuclear reactor provides total neutron flux of 3.3 X 10(4)n cm-2 s-1 on the surface of a vertical beam tube to which a liquid phantom is positioned. The capability of such a partial-body irradiation facility is demonstrated by measuring trace amounts of toxic cadmium in kidney. The detection limit of Cd in kidney for a skin dose of 1.66 mSv (166 mrem) is 1.34 mg under 500 s irradiation. This facility therefore combines the advantages of mobility with high sensitivity of detection of a toxic element under low neutron and gamma doses.

  4. Restricted mobility of specific functional groups reduces anti-cancer drug activity in healthy cells

    PubMed Central

    Martins, Murillo L.; Ignazzi, Rosanna; Eckert, Juergen; Watts, Benjamin; Kaneno, Ramon; Zambuzzi, Willian F.; Daemen, Luke; Saeki, Margarida J.; Bordallo, Heloisa N.

    2016-01-01

    The most common cancer treatments currently available are radio- and chemo-therapy. These therapies have, however, drawbacks, such as, the reduction in quality of life and the low efficiency of radiotherapy in cases of multiple metastases. To lessen these effects, we have encapsulated an anti-cancer drug into a biocompatible matrix. In-vitro assays indicate that this bio-nanocomposite is able to interact and cause morphological changes in cancer cells. Meanwhile, no alterations were observed in monocytes and fibroblasts, indicating that this system might carry the drug in living organisms with reduced clearance rate and toxicity. X-rays and neutrons were used to investigate the carrier structure, as well as to assess the drug mobility within the bio-nanocomposite. From these unique data we show that partial mobility restriction of active groups of the drug molecule suggests why this carrier design is potentially safer to healthy cells. PMID:26932808

  5. Restricted mobility of specific functional groups reduces anti-cancer drug activity in healthy cells.

    PubMed

    Martins, Murillo L; Ignazzi, Rosanna; Eckert, Juergen; Watts, Benjamin; Kaneno, Ramon; Zambuzzi, Willian F; Daemen, Luke; Saeki, Margarida J; Bordallo, Heloisa N

    2016-01-01

    The most common cancer treatments currently available are radio- and chemo-therapy. These therapies have, however, drawbacks, such as, the reduction in quality of life and the low efficiency of radiotherapy in cases of multiple metastases. To lessen these effects, we have encapsulated an anti-cancer drug into a biocompatible matrix. In-vitro assays indicate that this bio-nanocomposite is able to interact and cause morphological changes in cancer cells. Meanwhile, no alterations were observed in monocytes and fibroblasts, indicating that this system might carry the drug in living organisms with reduced clearance rate and toxicity. X-rays and neutrons were used to investigate the carrier structure, as well as to assess the drug mobility within the bio-nanocomposite. From these unique data we show that partial mobility restriction of active groups of the drug molecule suggests why this carrier design is potentially safer to healthy cells. PMID:26932808

  6. Restricted mobility of specific functional groups reduces anti-cancer drug activity in healthy cells

    NASA Astrophysics Data System (ADS)

    Martins, Murillo L.; Ignazzi, Rosanna; Eckert, Juergen; Watts, Benjamin; Kaneno, Ramon; Zambuzzi, Willian F.; Daemen, Luke; Saeki, Margarida J.; Bordallo, Heloisa N.

    2016-03-01

    The most common cancer treatments currently available are radio- and chemo-therapy. These therapies have, however, drawbacks, such as, the reduction in quality of life and the low efficiency of radiotherapy in cases of multiple metastases. To lessen these effects, we have encapsulated an anti-cancer drug into a biocompatible matrix. In-vitro assays indicate that this bio-nanocomposite is able to interact and cause morphological changes in cancer cells. Meanwhile, no alterations were observed in monocytes and fibroblasts, indicating that this system might carry the drug in living organisms with reduced clearance rate and toxicity. X-rays and neutrons were used to investigate the carrier structure, as well as to assess the drug mobility within the bio-nanocomposite. From these unique data we show that partial mobility restriction of active groups of the drug molecule suggests why this carrier design is potentially safer to healthy cells.

  7. Restricted mobility of specific functional groups reduces anti-cancer drug activity in healthy cells

    DOE PAGES

    Martins, Murillo L.; Ignazzi, Rosanna; Eckert, Juergen; Watts, Benjamin; Kaneno, Ramon; Zambuzzi, Willian F.; Daemen, Luke; Saeki, Margarida J.; Bordallo, Heloisa N.

    2016-03-02

    Here, the most common cancer treatments currently available are radio- and chemo-therapy. These therapies have, however, drawbacks, such as, the reduction in quality of life and the low efficiency of radiotherapy in cases of multiple metastases. To lessen these effects, we have encapsulated an anti-cancer drug into a biocompatible matrix. In-vitro assays indicate that this bio-nanocomposite is able to interact and cause morphological changes in cancer cells. Meanwhile, no alterations were observed in monocytes and fibroblasts, indicating that this system might carry the drug in living organisms with reduced clearance rate and toxicity. X-rays and neutrons were used to investigatemore » the carrier structure, as well as to assess the drug mobility within the bio-nanocomposite. In conclusion, from these unique data we show that partial mobility restriction of active groups of the drug molecule suggests why this carrier design is potentially safer to healthy cells.« less

  8. Preparation and characterization of TiO 2-cationic hybrid nanoparticles as electrophoretic particles

    NASA Astrophysics Data System (ADS)

    Li, Jingjing; Deng, Liandong; Xing, Jinfeng; Dong, Anjie; Li, Xianggao

    2012-01-01

    The hybrid nanoparticles (TiO2-HNPs) with TiO2 nanoparticles as core and with poly(N,N-dimethylaminoethyl methacrylate-co-methyl methacrylate) by using triallylamine as cross-linking agent as shell were firstly prepared via atom transfer radical polymerization (ATRP) in methanol. Then the hybrid nanoparticles with positive charge were produced by the quaternization with methyl iodide as quaternization reagent so as to endow them with greater electrophoretic mobility. The cationic hybrid nanoparticles (TiO2-CHNPs) were studied by means of transmission electron microscopy (TEM), scanning electron microscopy (SEM), Fourier-transform infrared (FTIR) spectroscopy and dynamic light scattering (DLS) measurements. The results indicate that the cationic polymer is successfully grafted on the surface of the TiO2 nanoparticles. The particle size of TiO2-CHNPs is about 150 nm and the polydispersity index (PDI) is 0.307. The zeta potential, the contrast ratio of white state to dark state and response time of TiO2-CHNPs are +16.8 mV, 30 and 3 s, respectively, which show the potential application prospect in the development of electrophoretic ink.

  9. Intra-Urban Human Mobility and Activity Transition: Evidence from Social Media Check-In Data

    PubMed Central

    Wu, Lun; Zhi, Ye; Sui, Zhengwei; Liu, Yu

    2014-01-01

    Most existing human mobility literature focuses on exterior characteristics of movements but neglects activities, the driving force that underlies human movements. In this research, we combine activity-based analysis with a movement-based approach to model the intra-urban human mobility observed from about 15 million check-in records during a yearlong period in Shanghai, China. The proposed model is activity-based and includes two parts: the transition of travel demands during a specific time period and the movement between locations. For the first part, we find the transition probability between activities varies over time, and then we construct a temporal transition probability matrix to represent the transition probability of travel demands during a time interval. For the second part, we suggest that the travel demands can be divided into two classes, locationally mandatory activity (LMA) and locationally stochastic activity (LSA), according to whether the demand is associated with fixed location or not. By judging the combination of predecessor activity type and successor activity type we determine three trip patterns, each associated with a different decay parameter. To validate the model, we adopt the mechanism of an agent-based model and compare the simulated results with the observed pattern from the displacement distance distribution, the spatio-temporal distribution of activities, and the temporal distribution of travel demand transitions. The results show that the simulated patterns fit the observed data well, indicating that these findings open new directions for combining activity-based analysis with a movement-based approach using social media check-in data. PMID:24824892

  10. Leisure Engagement: Medical Conditions, Mobility Difficulties, and Activity Limitations—A Later Life Perspective

    PubMed Central

    Nilsson, Ingeborg; Nyqvist, Fredrica; Gustafson, Yngve; Nygård, Mikael

    2015-01-01

    Objectives. This study aims to investigate the impact of medical conditions, mobility difficulties, and activity limitations on older people's engagement in leisure activities. Methods. The analyses are based on a cross regional survey carried out in 2010 in the Bothnia region (Northern Sweden and Western Finland). A posted questionnaire, which included questions on different aspects of leisure engagement, medical history, and health, was sent out to older persons in the region. The final sample consisted of 5435 persons aged 65, 70, 75, and 80 years. The data was analyzed by using ordinary least squares (OLS) multivariate regression. Results. The most important predictor of leisure engagement abstention among older people is the prevalence of activity limitations, whereas mobility difficulties and medical conditions play less important roles. The strong negative association between activity limitations and leisure engagement remains significant even after we control for individual, sociodemographic characteristics, and country. Discussion. This study provides a window into leisure engagement in later life and factors influencing the magnitude of engagement in leisure activities. PMID:26346706

  11. High charged red pigment nanoparticles for electrophoretic displays

    NASA Astrophysics Data System (ADS)

    Hou, Xin-Yan; Bian, Shu-Guang; Chen, Jian-Feng; Le, Yuan

    2012-12-01

    Organic pigment permanent red F2R nanoparticles were prepared via surface modification to improve the surface charge and dispersion ability in organic medium. Their large surface chargeability is confirmed by ζ-potential value of -49.8 mV. The prepared particles exhibited average size of 105 nm and showed very narrow distribution with polydispersity index of 0.068. The sedimentation ratio of the prepared particles in tetrachloroethylene was less than 5% within 12 days. The electrophoretic inks consisting of the prepared red particles with white particles as contrast showed good electrophoretic display, its refresh time was 200 ms.

  12. Importance of temperature effect on the electrophoretic behavior of charge-regulated particles.

    PubMed

    Hsu, Jyh-Ping; Tai, Yi-Hsuan; Yeh, Li-Hsien; Tseng, Shiojenn

    2012-01-10

    The Joule heating effect is inevitable in electrophoresis operations. To assess its influence on the performance of electrophoresis, we consider the case of a charge-regulated particle in a solution containing multiple ionic species at temperatures ranging from 298 to 308 K. Using an aqueous SiO(2) dispersion as an example, we show that an increase in the temperature leads to a decrease in both the dielectric constant and the viscosity of the liquid phase, and an increase in both the diffusivity of ions and the particle surface potential. For a particle having a constant surface potential, its electrophoretic mobility is most influenced by the variation in the liquid viscosity as the temperature varies, but for a charged-regulated particle both the liquid viscosity and the surface potential can play an important role. Depending upon the level of pH, the degree of increase in the mobility can be on the order of 40% for a 5 K increase in the temperature. The presence of double-layer polarization, which is significant when the surface potential is sufficiently high, has the effect of inhibiting that increase in the mobility. This implies that the influence of the temperature on the mobility of the particle is most significant when the pH is close to the point of zero charge. PMID:22126364

  13. Effects of Carbon in Flooded Paddy Soils: Implications for Microbial Activity and Arsenic Mobilization

    NASA Astrophysics Data System (ADS)

    Avancha, S.; Boye, K.

    2014-12-01

    In the Mekong delta in Cambodia, naturally occurring arsenic (originating from erosion in the Himalaya Mountains) in paddy soils is mobilized during the seasonal flooding. As a consequence, rice grown on the flooded soils may take up arsenic and expose people eating the rice to this carcinogenic substance. Microbial activity will enhance or decrease the mobilization of arsenic depending on their metabolic pathways. Among the microbes naturally residing in the soil are denitrifying bacteria, sulfate reducers, metal reducers (Fe, Mn), arsenic reducers, methanogens, and fermenters, whose activity varies based on the presence of oxygen. The purpose of the experiment was to assess how different amendments affect the microbial activity and the arsenic mobilization during the transition from aerobic to anaerobic metabolism after flooding of naturally contaminated Cambodian soil. In a batch experiment, we investigated how the relative metabolic rate of naturally occurring microbes could vary with different types of organic carbon. The experiment was designed to measure the effects of various sources of carbon (dried rice straw, charred rice straw, manure, and glucose) on the microbial activity and arsenic release in an arsenic-contaminated paddy soil from Cambodia under flooded conditions. All amendments were added based on the carbon content in order to add 0.036 g of carbon per vial. The soil was flooded with a 10mM TRIS buffer solution at pH 7.04 in airtight 25mL serum vials and kept at 25 °C. We prepared 14 replicates per treatment to sample both gas and solution. On each sampling point, the solution replicates were sampled destructively. The gas replicates continued on and were sampled for both gas and solution on the final day of the experiment. We measured pH, total arsenic, methane, carbon dioxide, and nitrous oxide at 8 hours, 1.5 days, 3.33 days, and 6.33 days from the start of the experiment.

  14. Locust flight activity as a model for hormonal regulation of lipid mobilization and transport.

    PubMed

    Van der Horst, Dick J; Rodenburg, Kees W

    2010-08-01

    Flight activity of insects provides a fascinating yet relatively simple model system for studying the regulation of processes involved in energy metabolism. This is particularly highlighted during long-distance flight, for which the locust constitutes a long-standing favored model insect, which as one of the most infamous agricultural pests additionally has considerable economical importance. Remarkably many aspects and processes pivotal to our understanding of (neuro)hormonal regulation of lipid mobilization and transport during insect flight activity have been discovered in the locust; among which are the peptide adipokinetic hormones (AKHs), synthesized and stored by the neurosecretory cells of the corpus cardiacum, that regulate and integrate lipid (diacylglycerol) mobilization and transport, the functioning of the reversible conversions of lipoproteins (lipophorins) in the hemolymph during flight activity, revealing novel concepts for the transport of lipids in the circulatory system, and the structure and functioning of the exchangeable apolipopotein, apolipophorin III, which exhibits a dual capacity to exist in both lipid-bound and lipid-free states that is essential to these lipophorin conversions. Besides, the lipophorin receptor (LpR) was identified and characterized in the locust. In an integrative approach, this short review aims at highlighting the locust as an unrivalled model for studying (neuro)hormonal regulation of lipid mobilization and transport during insect flight activity, that additionally has offered a broad and profound research model for integrative physiology and biochemistry, and particularly focuses on recent developments in the concept of AKH-induced changes in the lipophorin system during locust flight, that deviates fundamentally from the lipoprotein-based transport of lipids in the circulation of mammals. Current studies in this field employing the locust as a model continue to attribute to its role as a favored model organism, but

  15. Damping Control of Liquid Container by Swing-type Active Vibration Reducer on Mobile Robot

    NASA Astrophysics Data System (ADS)

    Hamaguchi, Masafumi; Taniguchi, Takao

    This paper proposes a damping control of sloshing in a cylindrical container with a swing-type active vibration reducer on a wheeled mobile robot (WMR). The WMR runs along a straight path on a horizontal plane. The container is mounted on the active vibration reducer. A laser displacement sensor is used to observe the liquid level in the container. The container can be tilted in the running direction by the active vibration reducer. A sloshing model is obtained from a spherical pendulum-type sloshing model, which approximately expresses (1, 1)-mode sloshing. The sloshing model is used to design a damping control system. The control system of the active vibration reducer is designed with an inverse model of sloshing and an optimal regulator with a Kalman filter. The WMR is driven by an acceleration pattern designed with an input shaping method. The usefulness of the proposed method is demonstrated through simulation and experimental results.

  16. Effects of motor patterns on water-soluble and membrane proteins and cholinesterase activity in subcellular fractions of rat brain tissue

    NASA Technical Reports Server (NTRS)

    Pevzner, L. Z.; Venkov, L.; Cheresharov, L.

    1980-01-01

    Albino rats were kept for a year under conditions of daily motor load or constant hypokinesia. An increase in motor activity results in a rise in the acetylcholinesterase activity determined in the synaptosomal and purified mitochondrial fractions while hypokinesia induces a pronounced decrease in this enzyme activity. The butyrylcholinesterase activity somewhat decreases in the synaptosomal fraction after hypokinesia but does not change under the motor load pattern. Motor load causes an increase in the amount of synaptosomal water-soluble proteins possessing an intermediate electrophoretic mobility and seem to correspond to the brain-specific protein 14-3-2. In the synaptosomal fraction the amount of membrane proteins with a low electrophoretic mobility and with the cholinesterase activity rises. Hypokinesia, on the contrary, decreases the amount of these membrane proteins.

  17. Neighbourhoods for Active Kids: study protocol for a cross-sectional examination of neighbourhood features and children's physical activity, active travel, independent mobility and body size

    PubMed Central

    Oliver, Melody; McPhee, Julia; Carroll, Penelope; Ikeda, Erika; Mavoa, Suzanne; Mackay, Lisa; Kearns, Robin A; Kyttä, Marketta; Asiasiga, Lanuola; Garrett, Nicholas; Lin, Judy; Mackett, Roger; Zinn, Caryn; Moewaka Barnes, Helen; Egli, Victoria; Prendergast, Kate; Witten, Karen

    2016-01-01

    Introduction New Zealand children's physical activity, including independent mobility and active travel, has declined markedly over recent decades. The Neighbourhoods for Active Kids (NfAK) study examines how neighbourhood built environments are associated with the independent mobility, active travel, physical activity and neighbourhood experiences of children aged 9–12 years in primary and intermediate schools across Auckland, New Zealand's largest city. Methods and analysis Child-specific indices of walkability, destination accessibility and traffic exposure will be constructed to measure the built environment in 8 neighbourhoods in Auckland. Interactive online-mapping software will be used to measure children's independent mobility and transport mode to destinations and to derive measures of neighbourhood use and perceptions. Physical activity will be measured using 7-day accelerometry. Height, weight and waist circumference will be objectively measured. Parent telephone interviews will collect sociodemographic information and parent neighbourhood perceptions. Interviews with school representative will capture supports and barriers for healthy activity and nutrition behaviours at the school level. Multilevel modelling approaches will be used to understand how differing built environment variables are associated with activity, neighbourhood experiences and health outcomes. Discussion We anticipate that children who reside in neighbourhoods considered highly walkable will be more physically active, accumulate more independent mobility and active travel, and be more likely to have a healthy body size. This research is timely as cities throughout New Zealand develop and implement plans to improve the liveability of intensifying urban neighbourhoods. Results will be disseminated to participants, local government agencies and through conventional academic avenues. PMID:27531740

  18. Computer simulation of two electrophoretic columns coupled for isoelectric focusing in simple buffers

    NASA Technical Reports Server (NTRS)

    Tsai, Amos; Mosher, Richard A.; Bier, Milan

    1986-01-01

    Computer simulation is used to analyze a system of two electrophoretic columns coupled by mixing the anolyte of one with the catholyte of the other. A mathematical model is presented which is used to predict the pH gradients formed by monovalent buffers in this system, when the currents in the columns are unequal. In the column with the higher current a pH gradient is created which increases from anode to cathode and is potentially useful for isoelectric focusing. The breadth of this gradient is dependent upon the ratio of the currents. The function of the second column is the compensation of buffer migration which occurs in the first column, thereby maintaining constant electrolyte composition. The effects of buffer pKs and mobilities are evaluated.

  19. Investigation of the free flow electrophoretic process. Volume 2: Technical analysis

    NASA Technical Reports Server (NTRS)

    Weiss, R. A.; Lanham, J. W.; Richman, D. W.; Walker, C. D.

    1979-01-01

    The effect of gravity on the free flow electrophoretic process was investigated. The demonstrated effects were then compared with predictions made by mathematical models. Results show that the carrier buffer flow was affected by gravity induced thermal convection and that the movement of the separating particle streams was affected by gravity induced buoyant forces. It was determined that if gravity induced buoyant forces were included in the mathematical models, then effective predictions of electrophoresis chamber separation performance were possible. The results of tests performed using various methods of electrophoresis using supportive media show that the mobility and the ability to separate were essentially independent of concentration, providing promise of being able to perform electrophoresis with higher inlet concentrations in space.

  20. Activation of vegetated parabolic dunes into mobile barchans under potential environmental change scenarios

    NASA Astrophysics Data System (ADS)

    Yan, Na; Baas, Andreas C. W.

    2016-04-01

    Parabolic dunes are a quintessential example of the co-evolution of soil, landform, and vegetation, and they are found around the world, on coasts, river valleys, lake shores, and margins of deserts and steppes. These areas are often sensitive to changes in natural and anthropogenic forcings and socio-economic activities. Some studies have indicated parabolic dunes can lose vegetation and transform into barchan and transverse dunes by environmental change such as decreased precipitation or lowered water table, as well as anthropogenic stress such as increased burning and grazing. These transformations and shifts between states of eco-geomorphic systems may have significant implications on land management and social-economic development. This study utilises the Extended-DECAL - parameterised by field measurements of dune topography and vegetation characteristics combined with remote sensing - to explore how increases in drought stress, wind strength, and grazing stress may lead to the activation of stabilised parabolic dunes into highly mobile barchans. The modelling results show that the mobility of an initial parabolic dune at the outset of perturbations determines to a large extent the capacity of a system to absorb the environmental change, and a slight increase in vegetation cover of an initial parabolic dune can increase the activation threshold significantly. Plants with a higher deposition tolerance increase the activation threshold for the climatic impact and sand transport rate, whereas the erosion tolerance of plants influences the patterns of resulting barchans. The change in the characteristics of eco-geomorphic interaction zones may indirectly reflect the dune stability and predict an ongoing transformation, whilst the activation angle may be potentially used as a proxy of environmental stresses. In contrast to the natural environmental changes which tend to affect relatively weak and young plants, grazing stress can exert a broader impact on all

  1. 21 CFR 864.7440 - Electrophoretic hemoglobin analysis system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Electrophoretic hemoglobin analysis system. 864.7440 Section 864.7440 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Kits and Packages §...

  2. 21 CFR 864.7440 - Electrophoretic hemoglobin analysis system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Electrophoretic hemoglobin analysis system. 864.7440 Section 864.7440 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Kits and Packages §...

  3. 21 CFR 864.7440 - Electrophoretic hemoglobin analysis system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Electrophoretic hemoglobin analysis system. 864.7440 Section 864.7440 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Kits and Packages §...

  4. 21 CFR 864.7440 - Electrophoretic hemoglobin analysis system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Electrophoretic hemoglobin analysis system. 864.7440 Section 864.7440 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Kits and Packages §...

  5. 21 CFR 864.7440 - Electrophoretic hemoglobin analysis system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Electrophoretic hemoglobin analysis system. 864.7440 Section 864.7440 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Kits and Packages §...

  6. Monodisperse light color nanoparticle ink toward chromatic electrophoretic displays

    NASA Astrophysics Data System (ADS)

    Peng, Bo; Li, Yue; Li, Jian; Bi, Lei; Lu, Haipeng; Xie, Jianliang; Ren, Xiangling; Cao, Yonghai; Wang, Ning; Meng, Xianwei; Deng, Longjiang; Guo, Zhanhu

    2016-05-01

    The facile synthesis of nanoparticles for precise image control and fast response of chromatic electrophoretic displays (EPDs) is a challenge. Herein, we report a general method to prepare pink, blue, and yellow nanoparticles with low density and a tunable size of 230-310 nm. The monodispersity is down to 0.02 and surface charges are up to 666e. Importantly, our work highlights the feasibility of chromatic nanoparticles as cost-effective candidates for electrophoretic displays.The facile synthesis of nanoparticles for precise image control and fast response of chromatic electrophoretic displays (EPDs) is a challenge. Herein, we report a general method to prepare pink, blue, and yellow nanoparticles with low density and a tunable size of 230-310 nm. The monodispersity is down to 0.02 and surface charges are up to 666e. Importantly, our work highlights the feasibility of chromatic nanoparticles as cost-effective candidates for electrophoretic displays. Electronic supplementary information (ESI) available. See DOI: 10.1039/c6nr02524b

  7. Electrophoretic separation of human kidney cells at zero gravity

    NASA Technical Reports Server (NTRS)

    Barlow, G. H.; Lazer, S. L.; Rueter, A.; Allen, R. E.

    1977-01-01

    Electrophoretic isolation of cells results in a loss of resolution power caused by the sedimentation of the cells in the media. The results of an experiment to extract urokinase from human embryos during the Apollo Soyuz mission are presented and discussed.

  8. Differential mitotic activation of endogenous c-Src, c-Yes, and Lyn in HeLa cells.

    PubMed

    Kuga, Takahisa; Nakayama, Yuji; Hoshino, Masaki; Higashiyama, Yukihiro; Obata, Yuuki; Matsuda, Daisuke; Kasahara, Kousuke; Fukumoto, Yasunori; Yamaguchi, Naoto

    2007-10-01

    Src-family tyrosine kinases (SFKs) play an important role in mitosis. Despite overlapping expression of multiple SFK members, little is known about how individual SFK members are activated in M phase. Here, we examined mitotic activation of endogenous c-Src, c-Yes, and Lyn, which are co-expressed in HeLa cells. c-Src, c-Yes, and Lyn were activated at different levels in M phase, and the activation was inhibited by Cdc2 inactivation. Mitotic c-Src and c-Yes exhibited normal- and retarded-electrophoretic-mobility forms on SDS-polyacrylamide gels, whereas Lyn did not show mobility retardation. Like c-Src, the retardation of electrophoretic mobility of c-Yes was caused by Cdc2-mediated phosphorylation. The normal- and retarded-mobility forms of c-Src were comparably activated, but activation of the retarded-mobility form of c-Yes was higher than that of the normal-mobility form of c-Yes. Thus, these results suggest that endogenous c-Src, c-Yes, and Lyn are differentially activated through Cdc2 activation during M phase.

  9. Active and reactive behaviour in human mobility: the influence of attraction points on pedestrians

    NASA Astrophysics Data System (ADS)

    Gutiérrez-Roig, M.; Sagarra, O.; Oltra, A.; Palmer, J. R. B.; Bartumeus, F.; Díaz-Guilera, A.; Perelló, J.

    2016-07-01

    Human mobility is becoming an accessible field of study, thanks to the progress and availability of tracking technologies as a common feature of smart phones. We describe an example of a scalable experiment exploiting these circumstances at a public, outdoor fair in Barcelona (Spain). Participants were tracked while wandering through an open space with activity stands attracting their attention. We develop a general modelling framework based on Langevin dynamics, which allows us to test the influence of two distinct types of ingredients on mobility: reactive or context-dependent factors, modelled by means of a force field generated by attraction points in a given spatial configuration and active or inherent factors, modelled from intrinsic movement patterns of the subjects. The additive and constructive framework model accounts for some observed features. Starting with the simplest model (purely random walkers) as a reference, we progressively introduce different ingredients such as persistence, memory and perceptual landscape, aiming to untangle active and reactive contributions and quantify their respective relevance. The proposed approach may help in anticipating the spatial distribution of citizens in alternative scenarios and in improving the design of public events based on a facts-based approach.

  10. Active and reactive behaviour in human mobility: the influence of attraction points on pedestrians.

    PubMed

    Gutiérrez-Roig, M; Sagarra, O; Oltra, A; Palmer, J R B; Bartumeus, F; Díaz-Guilera, A; Perelló, J

    2016-07-01

    Human mobility is becoming an accessible field of study, thanks to the progress and availability of tracking technologies as a common feature of smart phones. We describe an example of a scalable experiment exploiting these circumstances at a public, outdoor fair in Barcelona (Spain). Participants were tracked while wandering through an open space with activity stands attracting their attention. We develop a general modelling framework based on Langevin dynamics, which allows us to test the influence of two distinct types of ingredients on mobility: reactive or context-dependent factors, modelled by means of a force field generated by attraction points in a given spatial configuration and active or inherent factors, modelled from intrinsic movement patterns of the subjects. The additive and constructive framework model accounts for some observed features. Starting with the simplest model (purely random walkers) as a reference, we progressively introduce different ingredients such as persistence, memory and perceptual landscape, aiming to untangle active and reactive contributions and quantify their respective relevance. The proposed approach may help in anticipating the spatial distribution of citizens in alternative scenarios and in improving the design of public events based on a facts-based approach. PMID:27493774

  11. Active and reactive behaviour in human mobility: the influence of attraction points on pedestrians

    PubMed Central

    Sagarra, O.; Oltra, A.; Palmer, J. R. B.; Bartumeus, F.; Díaz-Guilera, A.; Perelló, J.

    2016-01-01

    Human mobility is becoming an accessible field of study, thanks to the progress and availability of tracking technologies as a common feature of smart phones. We describe an example of a scalable experiment exploiting these circumstances at a public, outdoor fair in Barcelona (Spain). Participants were tracked while wandering through an open space with activity stands attracting their attention. We develop a general modelling framework based on Langevin dynamics, which allows us to test the influence of two distinct types of ingredients on mobility: reactive or context-dependent factors, modelled by means of a force field generated by attraction points in a given spatial configuration and active or inherent factors, modelled from intrinsic movement patterns of the subjects. The additive and constructive framework model accounts for some observed features. Starting with the simplest model (purely random walkers) as a reference, we progressively introduce different ingredients such as persistence, memory and perceptual landscape, aiming to untangle active and reactive contributions and quantify their respective relevance. The proposed approach may help in anticipating the spatial distribution of citizens in alternative scenarios and in improving the design of public events based on a facts-based approach. PMID:27493774

  12. Transposable elements become active and mobile in the genomes of aging mammalian somatic tissues.

    PubMed

    De Cecco, Marco; Criscione, Steven W; Peterson, Abigail L; Neretti, Nicola; Sedivy, John M; Kreiling, Jill A

    2013-12-01

    Transposable elements (TEs) were discovered by Barbara McClintock in maize and have since been found to be ubiquitous in all living organisms. Transposition is mutagenic and organisms have evolved mechanisms to repress the activity of their endogenous TEs. Transposition in somatic cells is very low, but recent evidence suggests that it may be derepressed in some cases, such as cancer development. We have found that during normal aging several families of retrotransposable elements (RTEs) start being transcribed in mouse tissues. In advanced age the expression culminates in active transposition. These processes are counteracted by calorie restriction (CR), an intervention that slows down aging. Retrotransposition is also activated in age-associated, naturally occurring cancers in the mouse. We suggest that somatic retrotransposition is a hitherto unappreciated aging process. Mobilization of RTEs is likely to be an important contributor to the progressive dysfunction of aging cells. PMID:24323947

  13. Transposable elements become active and mobile in the genomes of aging mammalian somatic tissues.

    PubMed

    De Cecco, Marco; Criscione, Steven W; Peterson, Abigail L; Neretti, Nicola; Sedivy, John M; Kreiling, Jill A

    2013-12-01

    Transposable elements (TEs) were discovered by Barbara McClintock in maize and have since been found to be ubiquitous in all living organisms. Transposition is mutagenic and organisms have evolved mechanisms to repress the activity of their endogenous TEs. Transposition in somatic cells is very low, but recent evidence suggests that it may be derepressed in some cases, such as cancer development. We have found that during normal aging several families of retrotransposable elements (RTEs) start being transcribed in mouse tissues. In advanced age the expression culminates in active transposition. These processes are counteracted by calorie restriction (CR), an intervention that slows down aging. Retrotransposition is also activated in age-associated, naturally occurring cancers in the mouse. We suggest that somatic retrotransposition is a hitherto unappreciated aging process. Mobilization of RTEs is likely to be an important contributor to the progressive dysfunction of aging cells.

  14. Health-Promoting Physical Activity of Children Who Use Assistive Mobility Devices: A Scoping Review.

    PubMed

    Jirikowic, Tracy L; Kerfeld, Cheryl I

    2016-01-01

    Children with physical disabilities who use assistive mobility devices (AMDs) are at risk for obesity and other secondary health conditions. Habitual physical activity is one lifestyle factor that may prevent obesity and contribute to overall health, and an active lifestyle in childhood improves prospects for lifelong healthy behaviors. Child, family, and environmental facilitators and barriers influence health-promoting physical activity (HPPA) for children without disabilities, but comparable models and levels of understanding for children who use AMDs are lacking. In this scoping review, we identified a similar set of child, family, and environmental facilitators and barriers relevant to HPPA participation among children who use AMDs. Noted gaps in the literature included limited reporting of AMD use, inconsistent HPPA definitions, and inadequate measurement tools for children who are nonambulatory. The identified child, family, and environmental factors provide a framework for occupational therapy practitioners and interprofessional teams to develop HPPA opportunities and interventions for an underserved population. PMID:27548861

  15. Mobile Phone Use and its Association With Sitting Time and Meeting Physical Activity Recommendations in a Mexican American Cohort

    PubMed Central

    Chow, Wong-Ho; Daniel, Carrie R; Wu, Xifeng; Zhao, Hua

    2016-01-01

    Background The benefits of physical activity (PA) are well-documented. Mobile phones influence PA by promoting screen-based sedentary time, providing prompts or reminders to be active, aiding in tracking and monitoring PA, or providing entertainment during PA. It is not known how mobile phone use is associated with PA and sitting time in Mexican Americans, and how mobile phone users may differ from nonusers. Objective To determine the associations between mobile phone use, PA, and sitting time and how these behaviors differ from mobile phone nonusers in a sample of 2982 Mexican-American adults from the Mano a Mano cohort. Methods Differences in meeting PA recommendations and sitting time between mobile phone users and nonusers were examined using chi-square and analysis of variance tests. Logistic regression was used to examine associations between mobile phone use, PA, and sitting. Results Mobile phone users were more likely to be obese by body mass index criteria (≥30 kg/m2), younger, born in the United States and lived there longer, more educated, and sit more hours per day but more likely to meet PA recommendations than nonusers. Males (odds ratio [OR] 1.42, 95% CI 1.16-1.74), use of text messaging (OR 1.26, 95% CI 1.03-1.56), and having a higher acculturation score (OR 1.27, 95% CI 1.07-1.52) were associated with higher odds of meeting PA recommendations. Sitting more hours per day was associated with being male, obese, born in the United States, a former alcohol drinker, and having at least a high school education. Among nonusers, being born in the United States was associated with higher odds of more sitting time, and being married was associated with higher odds of meeting PA recommendations. Conclusions Mobile phone interventions using text messages could be tailored to promote PA in less acculturated and female Mexican American mobile phone users. PMID:27311831

  16. ELECTROKINETIC PHENOMENA : X. ELECTRIC MOBILITY AND CHARGE OF PROTEINS IN ALCOHOL-WATER MIXTURES.

    PubMed

    Daniel, J

    1933-01-20

    1. The electrophoretic velocities of gelatin-, egg-albumin-, and gliadin-covered quartz particles in various alcohol-water solutions are, within the limits employed in usual experimental procedures, proportional to the field strength. 2. The electrophoretic mobilities of small, irregularly shaped quartz particles covered with an adsorbed film of protein in alcohol-water solutions are equal to the electroosmotic mobilities of the liquid past similarly coated flat surfaces. Hence the size and shape of such particles does not influence their mobilities, which depend entirely on the protein film. 3. The corrected mobility and hence presumably the charge of gelatin-covered quartz particles in solutions containing 35 per cent ethyl alcohol is proportional to the combining power of the gelatin; therefore the gelatin is adsorbed with the active groups oriented toward the liquid. The same is true in 60 per cent alcohol. 4. The charge calculated by means of the Debye-Henry approximation from the mobility of gelatin in solutions containing up to 35 per cent ethyl alcohol is, in the neighborhood of the isoelectric point, proportional to the combining power of the gelatin. Therefore the dielectric constant and the viscosity of the bulk of the medium may be used in the Debye-Henry approximation Q = 6 pi eta r v(m) (1 + kappa r) to predict changes in charge from mobility. 5. In the neighborhood of the isoelectric point gelatin is probably completely ionized in buffered ethyl alcohol-water mixtures up to 60 per cent alcohol. 6. In the presence of ethyl alcohol the isoelectric point of gelatin is shifted toward smaller hydrogen ion activities. This shift, like that caused by alcohol in the isoelectric points of certain amino acids, is approximately linearly related to the dielectric constant of the medium.

  17. Electrophoretic behaviour of human urinary amylase

    PubMed Central

    Franzini, C.

    1965-01-01

    A saccharogenic method is described for estimating amylase activity in human urine. Results accord with those reported elsewhere except that in this study the peak in the beta zone is a new finding. Comparison between normal and pathological urines suggests that the amylase activity of the beta peak is not of pancreatic origin. PMID:5835450

  18. Atrial natriuretic peptide regulates lipid mobilization and oxygen consumption in human adipocytes by activating AMPK

    SciTech Connect

    Souza, Sandra C.; Chau, Mary D.L.; Yang, Qing; Gauthier, Marie-Soleil; Clairmont, Kevin B.; Wu, Zhidan; Gromada, Jesper; Dole, William P.

    2011-07-08

    Highlights: {yields} Treatment of differentiated human adipocytes with atrial natriuretic peptide (ANP) increased lipolysis and oxygen consumption by activating AMP-activated protein kinase (AMPK). {yields} ANP stimulated lipid mobilization by selective activation of the alpha2 subunit of AMPK and increased energy utilization through activation of both the alpha1 and alpha2 subunits of AMPK. {yields} ANP enhanced adipocyte mitochondrial oxidative capacity as evidenced by induction of oxidative mitochondrial genes and increase in oxygen consumption. {yields} Exposure of human adipocytes to fatty acids and (TNF{alpha}) induced insulin resistance and decreased expression of mitochondrial genes which was restored to normal by ANP. -- Abstract: Atrial natriuretic peptide (ANP) has been shown to regulate lipid and carbohydrate metabolism providing a possible link between cardiovascular function and metabolism by mediating the switch from carbohydrate to lipid mobilization and oxidation. ANP exerts a potent lipolytic effect via cGMP-dependent protein kinase (cGK)-I mediated-stimulation of AMP-activated protein kinase (AMPK). Activation of the ANP/cGK signaling cascade also promotes muscle mitochondrial biogenesis and fat oxidation. Here we demonstrate that ANP regulates lipid metabolism and oxygen utilization in differentiated human adipocytes by activating the alpha2 subunit of AMPK. ANP treatment increased lipolysis by seven fold and oxygen consumption by two fold, both of which were attenuated by inhibition of AMPK activity. ANP-induced lipolysis was shown to be mediated by the alpha2 subunit of AMPK as introduction of dominant-negative alpha2 subunit of AMPK attenuated ANP effects on lipolysis. ANP-induced activation of AMPK enhanced mitochondrial oxidative capacity as evidenced by a two fold increase in oxygen consumption and induction of mitochondrial genes, including carnitine palmitoyltransferase 1A (CPT1a) by 1.4-fold, cytochrome C (CytC) by 1.3-fold, and

  19. α-Lytic protease can exist in two separately stable conformations with different His57 mobilities and catalytic activities

    PubMed Central

    Haddad, Kristin Coffman; Sudmeier, James L.; Bachovchin, Daniel A.; Bachovchin, William W.

    2005-01-01

    α-Lytic protease is a bacterial serine protease widely studied as a model system of enzyme catalysis. Here we report that lyophilization induces a structural change in the enzyme that is not reversed by redissolution in water. The structural change reduces the mobility of the active-site histidine residue and the catalytic activity of the enzyme. The application of mild pressure to solutions of the altered enzyme reverses the lyophilization-induced structural change and restores the mobility of the histidine residue and the enzyme's catalytic activity. This effect of lyophilization permits a unique opportunity for investigating the relationship between histidine ring dynamics and catalytic activity. The results demonstrate that His57 in resting enzymes is more mobile than previously thought, especially when protonated. The histidine motion and its correlation to enzyme activity lend support to the reaction-driven ring flip hypothesis. PMID:15657134

  20. Development of the Barriers to Physical Activity Questionnaire for People with Mobility Impairments

    PubMed Central

    Vasudevan, Vijay; Rimmer, James H.; Kviz, Frederick

    2015-01-01

    Background Despite the widely known benefits of physical activity, people with disabilities are more likely to be inactive when compared to people without disabilities. Previous questionnaires that measure barriers physical activity for people with disabilities do not measure barriers from an ecological perspective. Objective The purpose of this study was to develop the Barriers to Physical Activity Questionnaire for People with Mobility Impairments (BPAQ-MI) that measures barriers using an ecological framework. Methods This study consisted of two phases. In Phase one, developed the content validity by (a) developing an item bank, (b) identifying missing items and combining items using a Delphi panel, and (c) refine item wording via cognitive interviews. In Phase two, people with mobility impairments took part in in-person interviews to establish test-retest reliability, internal consistency, and construct validity of the BPAQ-MI. Results Exploratory factor analysis revealed the BPAQ-MI was comprised of eight subscales or factors: health; beliefs and attitudes; family; friends; fitness center built environment; staff and policy; community built environment; and safety. The BPAQ-MI demonstrated very good test-retest reliability. Cronbach’s alpha ranged from 0.792 to 0.935. The BPAQ-MI showed significant negative correlations with exercise (minutes/week) and significant positive correlations between BPAQ-MI subscales and inactivity (hours/day). Conclusions The BPAQ-MI is the first questionnaire that places greater equity at measuring barriers to physical activity across the intrapersonal, interpersonal, organizational, and community domains. The BPAQ-MI has the potential to assist researchers in understanding the complex relationship between barriers and ultimately develop physical activity interventions that address these barriers. PMID:26087721

  1. Evidence of the activity of dissimilatory sulfate-reducing prokaryotes in nonsulfidogenic tropical mobile muds.

    PubMed

    Madrid, Vanessa M; Aller, Robert C; Aller, Josephine Y; Chistoserdov, Andrei Y

    2006-08-01

    In spite of the nonsulfidic conditions and abundant reactive iron(III) commonly found in mobile tropical deltaic muds, genes encoding dissimilatory sulfite reductase (dsr) were successfully amplified from the upper approximately 1 m of coastal deposits sampled along French Guiana and in the Gulf of Papua. The dsr sequences retrieved were highly diverse, were generally represented in both study regions and fell into six large phylogenetic groupings: Deltaproteobacteria, Thermodesulfovibrio groups, Firmicutes and three groups without known cultured representatives. The spatial and temporal distribution of dsr sequences strongly supports the contention that the sulfate-reducing prokaryote communities in mobile mud environments are cosmopolitan and stable over a period of years. The decrease in the (35)SO(4) (2-) tracer demonstrates that, despite abundant reactive sedimentary iron(III) ( approximately 350-400 mumol g(-1)), the sulfate-reducing prokaryotes present are active, with the highest levels of sulfide being generated in the upper zones of the cores (0-30 cm). Both the time course of the (35)S-sulfide tracer activity and the lack of reduced sulfur in sediments demonstrate virtually complete anaerobic loss of solid phase sulfides. We propose a pathway of organic matter oxidation involving at least 5-25% of the remineralized carbon, wherein sulfide produced by sulfate-reducing prokaryotes is cyclically oxidized biotically or abiotically by metal oxides.

  2. Increasing the Lifetime of Mobile WSNs via Dynamic Optimization of Sensor Node Communication Activity

    PubMed Central

    Guimarães, Dayan Adionel; Sakai, Lucas Jun; Alberti, Antonio Marcos; de Souza, Rausley Adriano Amaral

    2016-01-01

    In this paper, a simple and flexible method for increasing the lifetime of fixed or mobile wireless sensor networks is proposed. Based on past residual energy information reported by the sensor nodes, the sink node or another central node dynamically optimizes the communication activity levels of the sensor nodes to save energy without sacrificing the data throughput. The activity levels are defined to represent portions of time or time-frequency slots in a frame, during which the sensor nodes are scheduled to communicate with the sink node to report sensory measurements. Besides node mobility, it is considered that sensors’ batteries may be recharged via a wireless power transmission or equivalent energy harvesting scheme, bringing to the optimization problem an even more dynamic character. We report large increased lifetimes over the non-optimized network and comparable or even larger lifetime improvements with respect to an idealized greedy algorithm that uses both the real-time channel state and the residual energy information. PMID:27657075

  3. Outdoor Built Environment Barriers and Facilitators to Activity among Midlife and Older Adults with Mobility Disabilities

    PubMed Central

    Rosenberg, Dori E.

    2013-01-01

    Purpose: To gain better understanding of how the built environment impacts neighborhood-based physical activity among midlife and older adults with mobility disabilities. Design and methods: We conducted in-depth interviews with 35 adults over age 50, which used an assistive device and lived in King County, Washington, U.S. In addition, participants wore Global Positioning Systems (GPS) devices for 3 days prior to the interview. The GPS maps were used as prompts during the interviews. Open coding of the 35 interviews using latent content analysis resulted in key themes and subthemes that achieved consensus between coders. Two investigators independently coded the text of each interview. Results: Participants were on average of 67 years of age (range: 50–86) and predominantly used canes (57%), walkers (57%), or wheelchairs (46%). Key themes pertained to curb ramp availability and condition, sidewalk availability and condition, hills, aesthetics, lighting, ramp availability, weather, presence and features of crosswalks, availability of resting places and shelter on streets, paved or smooth walking paths, safety, and traffic on roads. Implications: A variety of built environment barriers and facilitators to neighborhood-based activity exist for midlife and older adults with mobility disabilities. Preparing our neighborhood environments for an aging population that uses assistive devices will be important to foster independence and health. PMID:23010096

  4. Norflurazon mobility, dissipation, activity, and persistence in a sandy soil as influenced by formulation.

    PubMed

    Sopeña, Fátima; Maqueda, Celia; Morillo, Esmeralda

    2007-05-01

    Five ethylcellulose (EC) microencapsulated formulations (MEFs) of norflurazon were prepared and applied in soil to study their mobility, dissipation, activity, and persistence. The results show that the release into water of norflurazon from EC microspheres was retarded when compared with that of commercial herbicide. The mobility of norflurazon from MEFs into soil columns has been greatly diminished in comparison with that of its current commercial formulation (CF). Norflurazon distribution at different depths in the soil was higher in the upper ring (up to 50% of the initial application). In contrast, the residues from commercial norflurazon along the complete soil column were only about 2%. Degradation and bioassay experiments showed that the MEFs had greater persistence (t1/2 values were 7.72 and 30.83 weeks for CF and MEFs, respectively) and herbicidal activity than the commercial formulation. The use of these formulations can be advantageous, because they can minimize the risk of groundwater contamination and permit herbicide use at reduced rates, maintaining the desired concentrations of herbicide in the topsoil layer for longer periods of weed control.

  5. Enabling Remote Activity: Using mobile technology for remote participation in geoscience fieldwork

    NASA Astrophysics Data System (ADS)

    Davies, Sarah; Collins, Trevor; Gaved, Mark; Bartlett, Jessica; Valentine, Chris; McCann, Lewis

    2010-05-01

    Field-based activities are regarded as essential to the development of a range of professional and personal skills within the geosciences. Students enjoy field activities, preferring these to learning with simulations (Spicer and Stratford 2001), and these improve deeper learning and understanding (Kern and Carpenter, 1984; Elkins and Elkins, 2007). However, some students find it difficult to access these field-based learning opportunities. Field sites may be remote and often require travel across uneven, challenging or potentially dangerous terrain. Mobility-impaired students are particularly limited in their opportunities to participate in field-based learning activities and, as higher education institutions have a responsibility to provide inclusive opportunities for students (UK Disability Discrimination Act 1995, UK Special Education Needs and Disability Rights Act 2001), the need for inclusive fieldwork learning is being increasingly recognised. The Enabling Remote Activity (ERA) project has been investigating how mobile communications technologies might allow field learning experiences to be brought to students who would otherwise find it difficult to participate, and also to enhance activities for all participants. It uses a rapidly deployable, battery-powered wireless network to transmit video, audio, and high resolution still images to connect participants at an accessible location with participants in the field. Crucially, the system uses a transient wireless network, allowing multiple locations to be explored during a field visit, and for plans to be changed dynamically if required. Central to the concept is the requirement for independent investigative learning: students are enabled to participate actively in the learning experience and to direct the investigations, as opposed to being simply remote viewers of the experience. Two ways of using the ERA system have been investigated: remote access and collaborative groupwork. In 2006 and 2008 remote

  6. Goal striving strategies and effort mobilization: When implementation intentions reduce effort-related cardiac activity during task performance.

    PubMed

    Freydefont, Laure; Gollwitzer, Peter M; Oettingen, Gabriele

    2016-09-01

    Two experiments investigate the influence of goal and implementation intentions on effort mobilization during task performance. Although numerous studies have demonstrated the beneficial effects of setting goals and making plans on performance, the effects of goals and plans on effort-related cardiac activity and especially the cardiac preejection period (PEP) during goal striving have not yet been addressed. According to the Motivational Intensity Theory, participants should increase effort mobilization proportionally to task difficulty as long as success is possible and justified. Forming goals and making plans should allow for reduced effort mobilization when participants perform an easy task. However, when the task is difficult, goals and plans should differ in their effect on effort mobilization. Participants who set goals should disengage, whereas participants who made if-then plans should stay in the field showing high effort mobilization during task performance. As expected, using an easy task in Experiment 1, we observed a lower cardiac PEP in both the implementation intention and the goal intention condition than in the control condition. In Experiment 2, we varied task difficulty and demonstrated that while participants with a mere goal intention disengaged from difficult tasks, participants with an implementation intention increased effort mobilization proportionally with task difficulty. These findings demonstrate the influence of goal striving strategies (i.e., mere goals vs. if-then plans) on effort mobilization during task performance.

  7. Variation in Activities of Amylase Allozymes Associated with Chromosome Inversions in DROSOPHILA PSEUDOOBSCURA, D. PERSIMILIS and D. MIRANDA

    PubMed Central

    Norman, R. A.; Prakash, Satya

    1980-01-01

    Different electrophoretic alleles of amylase show associations with particular chromosome 3 inversions in D. pseudoobscura and D. persimilis. Relative adult amylase activities were compared in 37, 37 and 10 strains of D. pseudoobscura, D. persimilis and D. miranda, respectively. Strains carrying the same electrophoretic allele were compared by crossing these lines individually to a reference strain carrying a different electrophoretic mobility allele. This procedure allows comparisons among species, inversions, electromorphs and strains for genetic variation in amylase activity. F2 analysis established that the activity variation co-segregates with the structural amylase locus. This type of variation could be due to either structural gene differences or differences in closely linked, cis-acting regulatory regions. Variation has been detected among and within electrophoretic mobility classes. Moreover, this variation is clearly nonrandom and reveals more of the genetic structure associated with the chromosomal inversion phylogeny of D. pseudoobscura and D. persimilis.—Some of the findings are: (1) Similar electromorphs in D. pseudoobscura and D. persimilis usually show different activities. These species show nearly complete differentiation of amylase alleles, based on activities. (2) D. persimilis has the broadest range of variation in amylase activity, about four-fold between the highest and lowest alleles. D. pseudoobscura and D. miranda are also polymorphic for activity, but have more constrained ranges of variation. D. miranda alleles show on the average about four times the activity of D. pseudoobscura alleles. (3) Some association of electrophoretic mobility and activity has been found. Alleles 1.09 of D. persimilis, as well as 1.43 and 1.55 of D. miranda, have relatively high activity. It may be that these high activity alleles are part of an adaptation to cooler habitats. (4) Within electrophoretic classes, associations of activities with inversions have

  8. Mobility of heavy metals from tailings to stream waters in a mining activity contaminated site.

    PubMed

    Concas, A; Ardau, C; Cristini, A; Zuddas, P; Cao, G

    2006-04-01

    In this paper the results of a recent characterization of Rio Piscinas (SW of Sardinia, Italy) hydrological basin are reported. In such area (about 50 km2), previous mining activities caused a serious heavy metal contamination of surface waters, groundwater, soils and biota. Acid mine drainage phenomena were observed in the area. The main sources of contamination are the tailings stored in mine tunnels and abandoned along fluvial banks. A methodological approach was adopted in order to identify relations between tailings and water contamination. Representative samples of tailings and stream sediments samples were collected. XRD analyses were performed for mineralogical characterization, while acid digestion was carried out for determining metal contents. Batch sequential leaching tests were performed in order to assess metal mobility. Also groundwater and stream water were sampled in specific locations and suitably characterized. All information collected allowed the understanding of the effect of tailings on water contamination, thus contributing to the qualitative prediction of pollution evolution on the basis of metal mobility. Finally, a potential remediation strategy of stream water is proposed.

  9. Supercapacitors using carbon nanotubes films by electrophoretic deposition

    NASA Astrophysics Data System (ADS)

    Du, Chunsheng; Pan, Ning

    Multi-walled carbon nanotube (MWNT) thin films have been fabricated by electrophoretic deposition technique in this study. The supercapacitors built from such thin film electrodes have exhibited near-ideal rectangular cyclic voltammograms even at a scan rate as high as 1000 mV s -1 and a high specific power density over 20 kW kg -1. More importantly, the supercapacitors showed superior frequency response, with a frequency 'knee' at about 7560 Hz, which is more than 70 times higher than the highest 'knee' frequency (100 Hz) so far reported for such supercapacitors. Our study also demonstrated that these carbon nanotube thin films can serve as a coating layer over ordinary current collectors to drastically enhance the electrode performance, indicating the huge potential in supercapacitor and battery manufacturing. Finally, it is clear that electrophoretic deposition is a promising technique for massive fabrication of carbon nanotube electrodes for various electronic devices.

  10. Preparation and properties of electrophoretic microcapsules for electronic paper.

    PubMed

    Song, J K; Choi, H J; Chin, I

    2007-02-01

    This paper shows two types of microcapsules used for electrophoretic display. One is prepared by in-situ polymerization which is based on urea, melamine and formaldehyde and another by complex coacervation, which is composed of gelatin and gum Arabic. Microcapsules attract interests of many research groups for longer lifetime of electrophoretic display by reducing agglomerization or lateral movements of nanoparticles. The gelatin microcapsules were more attractive in providing more uniform microcapsule coverage on electrodes due to their flexibility as compared to the melamine-urea microcapsules. The properties of microcapsules were characterized by FTIR, OM, SEM and TGA. Migration of nanoparticles in the two types of microcapsules was also observed when an electric field was applied.

  11. Submaximal oxygen uptake kinetics, functional mobility, and physical activity in older adults with heart failure and reduced ejection fraction

    PubMed Central

    Hummel, Scott L; Herald, John; Alpert, Craig; Gretebeck, Kimberlee A; Champoux, Wendy S; Dengel, Donald R; Vaitkevicius, Peter V; Alexander, Neil B

    2016-01-01

    Background Submaximal oxygen uptake measures are more feasible and may better predict clinical cardiac outcomes than maximal tests in older adults with heart failure (HF). We examined relationships between maximal oxygen uptake, submaximal oxygen kinetics, functional mobility, and physical activity in older adults with HF and reduced ejection fraction. Methods Older adults with HF and reduced ejection fraction (n = 25, age 75 ± 7 years) were compared to 25 healthy age- and gender-matched controls. Assessments included a maximal treadmill test for peak oxygen uptake (VO2peak), oxygen uptake kinetics at onset of and on recovery from a submaximal treadmill test, functional mobility testing [Get Up and Go (GUG), Comfortable Gait Speed (CGS), Unipedal Stance (US)], and self-reported physical activity (PA). Results Compared to controls, HF had worse performance on GUG, CGS, and US, greater delays in submaximal oxygen uptake kinetics, and lower PA. In controls, VO2peak was more strongly associated with functional mobility and PA than submaximal oxygen uptake kinetics. In HF patients, submaximal oxygen uptake kinetics were similarly associated with GUG and CGS as VO2peak, but weakly associated with PA. Conclusions Based on their mobility performance, older HF patients with reduced ejection fraction are at risk for adverse functional outcomes. In this population, submaximal oxygen uptake measures may be equivalent to VO2 peak in predicting functional mobility, and in addition to being more feasible, may provide better insight into how aerobic function relates to mobility in older adults with HF. PMID:27594875

  12. Submaximal oxygen uptake kinetics, functional mobility, and physical activity in older adults with heart failure and reduced ejection fraction

    PubMed Central

    Hummel, Scott L; Herald, John; Alpert, Craig; Gretebeck, Kimberlee A; Champoux, Wendy S; Dengel, Donald R; Vaitkevicius, Peter V; Alexander, Neil B

    2016-01-01

    Background Submaximal oxygen uptake measures are more feasible and may better predict clinical cardiac outcomes than maximal tests in older adults with heart failure (HF). We examined relationships between maximal oxygen uptake, submaximal oxygen kinetics, functional mobility, and physical activity in older adults with HF and reduced ejection fraction. Methods Older adults with HF and reduced ejection fraction (n = 25, age 75 ± 7 years) were compared to 25 healthy age- and gender-matched controls. Assessments included a maximal treadmill test for peak oxygen uptake (VO2peak), oxygen uptake kinetics at onset of and on recovery from a submaximal treadmill test, functional mobility testing [Get Up and Go (GUG), Comfortable Gait Speed (CGS), Unipedal Stance (US)], and self-reported physical activity (PA). Results Compared to controls, HF had worse performance on GUG, CGS, and US, greater delays in submaximal oxygen uptake kinetics, and lower PA. In controls, VO2peak was more strongly associated with functional mobility and PA than submaximal oxygen uptake kinetics. In HF patients, submaximal oxygen uptake kinetics were similarly associated with GUG and CGS as VO2peak, but weakly associated with PA. Conclusions Based on their mobility performance, older HF patients with reduced ejection fraction are at risk for adverse functional outcomes. In this population, submaximal oxygen uptake measures may be equivalent to VO2 peak in predicting functional mobility, and in addition to being more feasible, may provide better insight into how aerobic function relates to mobility in older adults with HF.

  13. Recrystallisation of electrophoretically deposited CdTe films

    NASA Astrophysics Data System (ADS)

    Pande, P. C.; Bocking, S.; Duke, S.; Miles, R. W.; Carter, M. J.; Latimer, I. D.; Hill, R.

    1996-02-01

    Films of CdTe have been produced by a novel low cost process based on electrophoretic deposition using polar organic solvents. The main advantage of this method is the high rate of deposition, greater than 20 μm/min. Details of the deposition process are given and the effects of post-deposition annealing of the samples have also been investigated using XRD, SEM and EDAX. Laser annealing resulted in melting of CdTe producing more compact and robust films.

  14. Parent-Targeted Mobile Phone Intervention to Increase Physical Activity in Sedentary Children: Randomized Pilot Trial

    PubMed Central

    Marker, Arwen M; Allen, H Raymond; Machtmes, Ryan; Han, Hongmei; Johnson, William D; Schuna Jr, John M; Broyles, Stephanie T; Tudor-Locke, Catrine; Church, Timothy S

    2014-01-01

    Background Low levels of moderate-to-vigorous physical activity are associated with adverse health consequences. Objective The intent of the study was to determine the feasibility and efficacy of a 12-week physical activity promotion program targeting children, which was delivered to parents through mobile phones. Methods Potential participants were recruited through advertisements placed in the newspaper, local hospitals and schools, and an email listserv. Sedentary children aged 6-10 years were randomly assigned to a minimal (MIG) or intensive (IIG) intervention group. Parents in the MIG were given a goal to increase (within 1 month) and maintain their child’s activity at 6000 pedometer steps/day above their baseline levels and to monitor their child’s steps daily. Parents in the IIG were given the same steps/day and monitoring goals, in addition to text messages and articles containing additional behavioral strategies (based on the Social Cognitive Theory) designed to promote their child’s physical activity. The intervention components were delivered via mobile phone. Anthropometrics, body composition, and questionnaires were administered in a clinic. Children wore a New Lifestyles pedometer (NL-1000) each day throughout the intervention and parents were to monitor their child’s step counts daily. Results Out of 59 children who screened for the study, a total of 27 children (mean age 8.7, SD 1.4 years; 56%, 15/27 female; 59%, 16/27 African American) were enrolled and completed the study. Overall, 97.90% (2220/2268; 98.20%, 1072/1092 for MIG; 97.60%, 1148/1176 for IIG) of expected step data were successfully entered by the parent or study coordinator. Parents in the MIG and IIG were sent approximately 7 and 13 text messages per week, respectively, averaged over the course of the study. IIG parents accessed an average of 6.1 (SD 4.4) articles over the course of the intervention and accessed a fewer number of articles in the last month compared to the first

  15. Primary patellar tendon repair and early mobilization: results in an active-duty population.

    PubMed

    Enad, J G; Loomis, L L

    2001-01-01

    We retrospectively reviewed 13 patellar tendon repairs done over 32 months at a tertiary care, military medical center. Early mobilization was initiated within 2 weeks postoperatively. Clinical and functional results were statistically examined with relation to age, timing of surgery, length of follow-up, quadriceps atrophy, extensor lag, patella position, and time to full duty. At an average of 24 months' follow-up, six patients (46%) had thigh girth atrophy, and one patient (8%) had an extensor lag >5 degrees. Mean Lysholm score was 84 (range, 57 to 100). Maximum postoperative Tegner activity scores averaged 7.1 (range, 5 to 10). Clinical results classified five cases as excellent, three good, three fair, and two poor. Functional results classified three cases as excellent, four good, two fair, and four poor. Time to return to duty averaged 13 months. Our results suggest that adequate extensor function can be restored after primary repair and immediate motion therapy.

  16. Study on the interaction of catechins with human serum albumin using spectroscopic and electrophoretic techniques

    NASA Astrophysics Data System (ADS)

    Trnková, Lucie; Boušová, Iva; Staňková, Veronika; Dršata, Jaroslav

    2011-01-01

    The interaction between eight naturally occurring flavanols (catechin, epicatechin, gallocatechin, epigallocatechin, catechin gallate, epicatechin gallate, gallocatechin gallate, and epigallocatechin gallate) and human serum albumin (HSA) has been investigated by spectroscopic (fluorescence quenching and UV-Vis absorption) and electrophoretic (native and SDS PAGE) techniques under simulated physiological conditions (pH 7.40, 37 °C). The spectroscopic results confirmed the complex formation for the tested systems. The binding constants and the number of binding sites were obtained by analysis of fluorescence data. The strongest binding affinity to HSA was found for epicatechin gallate and decreased in the order epicatechin gallate ⩾ catechin gallate > epigallocatechin gallate > gallocatechin gallate ≫ epicatechin ⩾ catechin > gallocatechin ⩾ epigallocatechin. All free energy changes possessed negative sign indicating the spontaneity of catechin-HSA systems formation. The binding distances between the donor (HSA) and the acceptors (catechins) estimated by the Förster theory revealed that non-radiation energy transfer from HSA to catechins occurred with high possibility. According to results obtained by native PAGE, the galloylated catechins increased the electrophoretic mobility of HSA, which indicated the change in the molecular charge of HSA, whilst the non-galloylated catechins caused no changes. The ability of aggregation and cross-linking of tested catechins with HSA was not proved by SDS-PAGE. The relationship between the structure characteristics of all tested catechins (e.g. presence of the galloyl moiety on the C-ring, the number of hydroxyl groups on the B-ring, and the spatial arrangement of the substituents on the C-ring) and their binding properties to HSA is discussed. The presented study contributes to the current knowledge in the area of protein-ligand binding, particularly catechin-HSA interactions.

  17. Antioxidant activity associated with lipid and phenolic mobilization during seed germination of Pangium edule Reinw.

    PubMed

    Andarwulan, N; Fardiaz, D; Wattimena, G A; Shetty, K

    1999-08-01

    Seeds of the tropical tree Pangium edule Reinw. are widely eaten in Southeast Asia after some treatment or processing. Fermented seeds are a specialty in Indonesia and have been used as spices. Because the tree is wild and has not been cultivated commercially, the physiology of germinated seeds of this tree for food uses is not known. This study reports some biochemical changes during seed germination associated with antioxidant activity and the mobilization of lipids and phenolics. Lipid content decreased, whereas the dominant fatty acids did not change significantly. The dominant fatty acids were oleic acid (C(18:1(n-9))) and linoleic acid (C(18:2(n-6))). During germination, oleic acid decreased while linoleic acid increased proportionally. The hypocotyl synthesized chlorophyll and the tocol composition also changed substantially. The antioxidant activity of phenolic extract increased in proportion to the total phenolics. Guaiacol peroxidase and glucose-6-phosphate dehydrogenase, selected enzymes association with phenolic metabolism, showed that the increased activities coincided with increased total phenolics and free proline. PMID:10552624

  18. Dynamic high-resolution computer simulation of electrophoretic enantiomer separations with neutral cyclodextrins as chiral selectors.

    PubMed

    Breadmore, Michael C; Kwan, Hiu Ying; Caslavska, Jitka; Thormann, Wolfgang

    2012-03-01

    GENTRANS, a comprehensive one-dimensional dynamic simulator for electrophoretic separations and transport, was extended for handling electrokinetic chiral separations with a neutral ligand. The code can be employed to study the 1:1 interaction of monovalent weak and strong acids and bases with a single monovalent weak or strong acid or base additive, including a neutral cyclodextrin, under real experimental conditions. It is a tool to investigate the dynamics of chiral separations and to provide insight into the buffer systems used in chiral capillary zone electrophoresis (CZE) and chiral isotachophoresis. Analyte stacking across conductivity and buffer additive gradients, changes of additive concentration, buffer component concentration, pH, and conductivity across migrating sample zones and peaks, and the formation and migration of system peaks can thereby be investigated in a hitherto inaccessible way. For model systems with charged weak bases and neutral modified β-cyclodextrins at acidic pH, for which complexation constants, ionic mobilities, and mobilities of selector-analyte complexes have been determined by CZE, simulated and experimentally determined electropherograms and isotachopherograms are shown to be in good agreement. Simulation data reveal that CZE separations of cationic enantiomers performed in phosphate buffers at low pH occur behind a fast cationic migrating system peak that has a small impact on the buffer composition under which enantiomeric separation takes place. PMID:22528416

  19. The application of machine learning in multi sensor data fusion for activity recognition in mobile device space

    NASA Astrophysics Data System (ADS)

    Marhoubi, Asmaa H.; Saravi, Sara; Edirisinghe, Eran A.

    2015-05-01

    The present generation of mobile handheld devices comes equipped with a large number of sensors. The key sensors include the Ambient Light Sensor, Proximity Sensor, Gyroscope, Compass and the Accelerometer. Many mobile applications are driven based on the readings obtained from either one or two of these sensors. However the presence of multiple-sensors will enable the determination of more detailed activities that are carried out by the user of a mobile device, thus enabling smarter mobile applications to be developed that responds more appropriately to user behavior and device usage. In the proposed research we use recent advances in machine learning to fuse together the data obtained from all key sensors of a mobile device. We investigate the possible use of single and ensemble classifier based approaches to identify a mobile device's behavior in the space it is present. Feature selection algorithms are used to remove non-discriminant features that often lead to poor classifier performance. As the sensor readings are noisy and include a significant proportion of missing values and outliers, we use machine learning based approaches to clean the raw data obtained from the sensors, before use. Based on selected practical case studies, we demonstrate the ability to accurately recognize device behavior based on multi-sensor data fusion.

  20. Ballistic abdominal exercises: muscle activation patterns during three activities along the stability/mobility continuum.

    PubMed

    McGill, Stuart M; Karpowicz, Amy; Fenwick, Chad M J

    2009-05-01

    The purpose of this study was to document the muscle activity and spine motion during several tasks requiring rapid abdominal contraction. Eight healthy men from a university population were instrumented to obtain surface electromyography of selected trunk and hip muscles, together with video analysis to calculate joint moments and electromagnetic lumbar spine position sensor to track spine posture. Exercises included a punch, throw, and a ballistic torso-stiffening maneuver. This study found that no muscle turned on significantly before any other muscle during both the 1-in. punch and ballistic torso-stiffening maneuver. Conversely, there was a significant order or muscle onset during the baseball throw. Muscles reached peak activation significantly before any other muscle during the baseball throw and 1-in. punch, but there were no significant differences for the torso-stiffening maneuver. The exercises quantified in this study demonstrated how muscle contraction dynamics change to meet differing demands for stiffening, for force/moment production, and for rapid movements. Specifically, it seems that there is an order of contraction when movement is the goal but not when just spine stability is required. Thus, a different intensity of abdominal bracing is required to achieve the different objectives of sports tasks and exercises.

  1. No evidence for cell activation or brain vaso-occlusion with plerixafor mobilization in sickle cell mice.

    PubMed

    Choi, Erika; Branch, Craig; Cui, Min-Hui; Yazdanbakhsh, Karina; Mohandas, Narla; Billett, Henny H; Shi, Patricia A

    2016-03-01

    Gene therapy for sickle cell disease is currently in active trials. Collecting hematopoietic progenitor cells safely and effectively is challenging, however, because granulocyte colony stimulating factor, the drug used most commonly for mobilization, can cause life-threatening vaso-occlusion in patients with sickle cell disease, and bone marrow harvest requires general anesthesia and multiple hip bone punctures. Plerixafor is an inhibitor of the CXCR4 chemokine receptor on hematopoietic progenitor cells, blocking its binding to SDF-1 (CXCL12) on bone marrow stroma. In support of a clinical trial in patients with sickle cell disease of plerixafor mobilization (NCT02193191), we administered plerixafor to sickle cell mice and found that it mobilizes hematopoietic progenitor cells without evidence of concomitant cell activation or brain vaso-occlusion.

  2. Electrophoretic separation and analysis of living cells from solid tissues by several methods - Human embryonic kidney cell cultures as a model

    NASA Technical Reports Server (NTRS)

    Todd, Paul; Plank, Lindsay D.; Kunze, M. Elaine; Lewis, Marian L.; Morrison, Dennis R.

    1986-01-01

    The use of free-fluid electrophoresis methods to separate tissue cells having a specific function is discussed. It is shown that cells suspended by trypsinization from cultures of human embryonic kidney are electrophoretically heterogeneous and tolerate a wide range of electrophoresis buffers and conditions without significant attenuation of function. Moreover, these cells do not separate electrophoretically on the basis of size or cell position alone and can be separated according to their ability to give rise to progeny that produce specific plasminogen activators.

  3. Superhydrophobic nanostructured ZnO thin films on aluminum alloy substrates by electrophoretic deposition process

    NASA Astrophysics Data System (ADS)

    Huang, Ying; Sarkar, D. K.; Chen, X.-Grant

    2015-02-01

    Superhydrophobic thin films have been fabricated on aluminum alloy substrates by electrophoretic deposition (EPD) process using stearic acid (SA) functionalized zinc oxide (ZnO) nanoparticles suspension in alcohols at varying bath temperatures. The deposited thin films have been characterized using both X-ray diffraction (XRD) and infrared (IR) spectroscopy and it is found that the films contain low surface energy zinc stearate and ZnO nanoparticles. It is also observed that the atomic percentage of Zn and O, roughness and water contact angle of the thin films increase with the increase of the deposited bath temperature. Furthermore, the thin film deposited at 50 °C, having a roughness of 4.54 ± 0.23 μm, shows superhydrophobic properties providing a water contact angle of 155 ± 3° with rolling off properties. Also, the activation energy of electrophoretic deposition of stearic-acid-functionalized ZnO nanoparticles is calculated to be 0.5 eV.

  4. p21-activated kinase regulates mast cell degranulation via effects on calcium mobilization and cytoskeletal dynamics

    PubMed Central

    Allen, Jayme D.; Jaffer, Zahara M.; Park, Su-Jung; Burgin, Sarah; Hofmann, Clemens; Sells, Mary Ann; Chen, Shi; Derr-Yellin, Ethel; Michels, Elizabeth G.; McDaniel, Andrew; Bessler, Waylan K.; Ingram, David A.; Atkinson, Simon J.; Travers, Jeffrey B.

    2009-01-01

    Mast cells are key participants in allergic diseases via activation of high-affinity IgE receptors (FcϵRI) resulting in release of proinflammatory mediators. The biochemical pathways linking IgE activation to calcium influx and cytoskeletal changes required for intracellular granule release are incompletely understood. We demonstrate, genetically, that Pak1 is required for this process. In a passive cutaneous anaphylaxis experiment, Wsh/Wsh mast cell–deficient mice locally reconstituted with Pak1−/− bone marrow–derived mast cells (BMMCs) experienced strikingly decreased allergen-induced vascular permeability compared with controls. Consistent with the in vivo phenotype, Pak1−/− BMMCs exhibited a reduction in FcϵRI-induced degranulation. Further, Pak1−/− BMMCs demonstrated diminished calcium mobilization and altered depolymerization of cortical filamentous actin (F-actin) in response to FcϵRI stimulation. These data implicate Pak1 as an essential molecular target for modulating acute mast cell responses that contribute to allergic diseases. PMID:19124833

  5. Plasmid metagenome reveals high levels of antibiotic resistance genes and mobile genetic elements in activated sludge.

    PubMed

    Zhang, Tong; Zhang, Xu-Xiang; Ye, Lin

    2011-01-01

    The overuse or misuse of antibiotics has accelerated antibiotic resistance, creating a major challenge for the public health in the world. Sewage treatment plants (STPs) are considered as important reservoirs for antibiotic resistance genes (ARGs) and activated sludge characterized with high microbial density and diversity facilitates ARG horizontal gene transfer (HGT) via mobile genetic elements (MGEs). However, little is known regarding the pool of ARGs and MGEs in sludge microbiome. In this study, the transposon aided capture (TRACA) system was employed to isolate novel plasmids from activated sludge of one STP in Hong Kong, China. We also used Illumina Hiseq 2000 high-throughput sequencing and metagenomics analysis to investigate the plasmid metagenome. Two novel plasmids were acquired from the sludge microbiome by using TRACA system and one novel plasmid was identified through metagenomics analysis. Our results revealed high levels of various ARGs as well as MGEs for HGT, including integrons, transposons and plasmids. The application of the TRACA system to isolate novel plasmids from the environmental metagenome, coupled with subsequent high-throughput sequencing and metagenomic analysis, highlighted the prevalence of ARGs and MGEs in microbial community of STPs.

  6. Results of the survey activities and mobile gamma scanning in Monticello, Utah

    SciTech Connect

    Little, C.A.; Berven, B.A.

    1985-11-01

    The town of Monticello, Utah, was once the site of an active mill which processed vanadium ore (1942 to 1948), and uranium ore (1948 to 1960). Properties in the vicinity of that mill have become contaminated with radioactive material from ore processing. The Radiological Survey Activities (RASA) group at Oak Ridge National Laboratory (ORNL) was requested by the Division of Remedial Action Projects (DRAP) in the Department of Energy (DOE) to: (1) identify potentially contaminated properties; (2) assess natural background radiation levels; and (3) rapidly assess the magnitude, extent, and type (i.e. ore, tailings, etc.) of contamination present on these properties (if any). This survey was conducted by RASA during April 1983. In addition to the 114 properties previously identified from historical information, the ORNL mobile gamma scanning van located 36 new properties exhibiting anomalous gamma radiation levels. Onsite surveys were conducted on 145 of the 150 total properties identified either historically or with the gamma scanning van. Of these 145 properties, 122 of them appeared to have some type of contaminated material present on them; however, only 48 appeared to be contaminated to the extent where they were in excess of Environmental Protection Agency (EPA) criteria (40 CFR 192). Twenty-one other properties were recommended for additional investigation (indoor gamma scanning and radon daughter measurements); of these, only ten required further analysis. This report provides the detailed data and analyses related to the radiological survey efforts performed by ORNL in Monticello, Utah.

  7. Venus Mobile Explorer with RPS for Active Cooling: A Feasibility Study

    NASA Technical Reports Server (NTRS)

    Leifer, Stephanie D.; Green, Jacklyn R.; Balint, Tibor S.; Manvi, Ram

    2009-01-01

    We present our findings from a study to evaluate the feasibility of a radioisotope power system (RPS) combined with active cooling to enable a long-duration Venus surface mission. On-board power with active cooling technology featured prominently in both the National Research Council's Decadal Survey and in the 2006 NASA Solar System Exploration Roadmap as mission-enabling for the exploration of Venus. Power and cooling system options were reviewed and the most promising concepts modeled to develop an assessment tool for Venus mission planners considering a variety of future potential missions to Venus, including a Venus Mobile Explorer (either a balloon or rover concept), a long-lived Venus static lander, or a Venus Geophysical Network. The concepts modeled were based on the integration of General Purpose Heat Source (GPHS) modules with different types of Stirling cycle heat engines for power and cooling. Unlike prior investigations which reported on single point design concepts, this assessment tool allows the user to generate either a point design or parametric curves of approximate power and cooling system mass, power level, and number of GPHS modules needed for a "black box" payload housed in a spherical pressure vessel.

  8. Cost effectiveness of the LIFE physical activity intervention for older adults at increased risk for mobility disability

    Technology Transfer Automated Retrieval System (TEKTRAN)

    BACKGROUND: Losing the ability to walk safely and independently is a major concern for many older adults. The Lifestyle Interventions and Independence for Elders study recently demonstrated that a physical activity (PA) intervention can delay the onset of major mobility disability. Our objective is ...

  9. Habitual physical activity levels are associated with performance in measures of physical function and mobility in older men

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Physical activity according to triaxial accelerometers; physical function and mobility according to the Short Physical Performance Battery (SPPB), gait speed, stair climb time, and a lift-and-lower task; aerobic capacity according to maximum oxygen consumption (VO(2) max); and leg press and chest pr...

  10. Mobility of University Staff.

    ERIC Educational Resources Information Center

    Council for Cultural Cooperation, Strasbourg (France).

    This study deals with interuniversity mobility. Part I examines the harmonization of action taken to encourage mobility, the removal of legislative and statutory obstacles to mobility, the simplification of university staff regulations and careers, and incentives to mobility. Part II describes the ideas and activities of UNESCO, the Council of…

  11. Enabling Remote Activity: Using mobile technology for remote participation in geoscience fieldwork

    NASA Astrophysics Data System (ADS)

    Davies, Sarah; Collins, Trevor; Gaved, Mark; Bartlett, Jessica; Valentine, Chris; McCann, Lewis

    2010-05-01

    Field-based activities are regarded as essential to the development of a range of professional and personal skills within the geosciences. Students enjoy field activities, preferring these to learning with simulations (Spicer and Stratford 2001), and these improve deeper learning and understanding (Kern and Carpenter, 1984; Elkins and Elkins, 2007). However, some students find it difficult to access these field-based learning opportunities. Field sites may be remote and often require travel across uneven, challenging or potentially dangerous terrain. Mobility-impaired students are particularly limited in their opportunities to participate in field-based learning activities and, as higher education institutions have a responsibility to provide inclusive opportunities for students (UK Disability Discrimination Act 1995, UK Special Education Needs and Disability Rights Act 2001), the need for inclusive fieldwork learning is being increasingly recognised. The Enabling Remote Activity (ERA) project has been investigating how mobile communications technologies might allow field learning experiences to be brought to students who would otherwise find it difficult to participate, and also to enhance activities for all participants. It uses a rapidly deployable, battery-powered wireless network to transmit video, audio, and high resolution still images to connect participants at an accessible location with participants in the field. Crucially, the system uses a transient wireless network, allowing multiple locations to be explored during a field visit, and for plans to be changed dynamically if required. Central to the concept is the requirement for independent investigative learning: students are enabled to participate actively in the learning experience and to direct the investigations, as opposed to being simply remote viewers of the experience. Two ways of using the ERA system have been investigated: remote access and collaborative groupwork. In 2006 and 2008 remote

  12. Built environment attributes related to GPS measured active trips in mid-life and older adults with mobility disabilities

    PubMed Central

    Gell, Nancy M.; Rosenberg, Dori E.; Carlson, Jordan; Kerr, Jacqueline; Belza, Basia

    2015-01-01

    Background Understanding factors which may promote walking in mid-life and older adults with mobility impairments is key given the association between physical activity and positive health outcomes. Objective To examine the relationship between active trips and objective measures of the home neighborhood built environment. Methods Global positioning systems (GPS) data collected on 28 adults age 50+ with mobility disabilities were analyzed for active trips from home. Objective and geographic information systems (GIS) derived measures included Walk Score, population density, street connectivity, crime rates, and slope within the home neighborhood. For this cross-sectional observational study, we conducted mean comparisons between participants who took active trips from home and those who did not for the objective measures. Effect sizes were calculated to assess the magnitude of group differences. Results Nine participants (32%) took active trips from home. Walking in the home neighborhood was significantly associated with GIS derived measures (Walk Score, population density, and street density; effect sizes .9-1.2). Participants who used the home neighborhood for active trips had less slope within 1 km of home but the difference was not significant (73.5 meters±22 vs. 100.8 meters ±38.1, p=.06, d=0.8). There were no statistically significant differences in mean scores for crime rates between those with active trips from home and those without. Conclusions The findings provide preliminary evidence that more walkable environments promote active mobility among mid-life and older adults with mobility disabilities. The data suggest that this population can and does use active transportation modes when the built environment is supportive. PMID:25637503

  13. Subsurface sediment mobilization and active pockmarks from sublacustrine ground-water seepage

    NASA Astrophysics Data System (ADS)

    Reusch, A.; Moernaut, J.; Loher, M.; Hilbe, M.; Meinecke, G.; Kipfer, R.; Anselmetti, F.; Bouffard, D.; Strasser, M.

    2014-12-01

    Lakes can be used as "model basins" to study fluid-flow processes with a multi-method approach in a well-defined environment. We present unprecedented insight into newly discovered pockmarks and associated subsurface sediment-mobilization structures in Lake Neuchâtel, Switzerland. A geophysical approach using multiple tools provides precise high-resolution bathymetric data and subsurface information of the sedimentary infill. We combine geophysical (300 kHz Kongsberg EM2040 multibeam, 3.5 kHz pinger seismic, deep-towed multi-frequency chirp seismic, mounted on an AUV), sedimentological (piston cores), hydrological (CTD), geochemical (methane, δ18O) and visual (ROV survey) data and observations. The data show several circular, crater-shaped pockmarks of up to 160 m in diameter and up to 30 m depth. The pockmarks are partially filled with mud in a fluid-like state. It is hypothesized that this mud is a result of active fluid flow within the pockmark. The levees of the pockmarks are characterized by high-amplitude wedge-shaped seismic reflections being intercalated with the background sediments. They are interpreted as overflow deposits originating from episodic increases in fluid flow from inside the pockmarks, causing sediment to be spilled over the margin and deposited on the levees. Data show multiple phases of sediment expulsion during discrete periods throughout the Holocene. Geochemical sediment analyses of headspace methane indicate the presence of purely microbial methane at low concentrations, thus no indications of active gas seepage. Elevated temperature values and depleted δ18O signals within the pockmark, compared to the reference sites, hint towards different water sources. We interpret these data to show two water bodies: (i) lake bottom-water, and (ii) groundwater entering as focused fluid flow through the pockmark. This multi-proxy approach shows that the newly discovered pockmarks of Lake Neuchâtel are sublacustrine springs, possibly related to

  14. Active ambulatory care management supported by short message services and mobile phone technology in patients with arterial hypertension.

    PubMed

    Kiselev, Anton R; Gridnev, Vladimir I; Shvartz, Vladimir A; Posnenkova, Olga M; Dovgalevsky, Pavel Ya

    2012-01-01

    The use of short message services and mobile phone technology for ambulatory care management is the most accessible and most inexpensive way to transition from traditional ambulatory care management to active ambulatory care management in patients with arterial hypertension (AH). The aim of this study was to compare the clinical efficacy of active ambulatory care management supported by short message services and mobile phone technology with traditional ambulatory care management in AH patients. The study included 97 hypertensive patients under active ambulatory care management and 102 patients under traditional ambulatory care management. Blood pressure levels, body mass, and smoking history of patients were analyzed in the study. The duration of study was 1 year. In the active ambulatory care management group, 36% of patients were withdrawn from the study within a year. At the end of the year, 77% of patients from the active care management group had achieved the goal blood pressure level. That was more than 5 times higher than that in the traditional ambulatory care management group (P < .001). The risk ratio of achieving and maintaining the goal blood pressure in patients of active care management group was 5.44, CI (3.2-9.9; P = .005). Implementation of active ambulatory care management supported by short message services and mobile phone improves the quality of ambulatory care of hypertensive patients.

  15. Selectively-etched nanochannel electrophoretic and electrochemical devices

    DOEpatents

    Surh, Michael P.; Wilson, William D.; Barbee, Jr., Troy W.; Lane, Stephen M.

    2004-11-16

    Nanochannel electrophoretic and electrochemical devices having selectively-etched nanolaminates located in the fluid transport channel. The normally flat surfaces of the nanolaminate having exposed conductive (metal) stripes are selectively-etched to form trenches and baffles. The modifications of the prior utilized flat exposed surfaces increase the amount of exposed metal to facilitate electrochemical redox reaction or control the exposure of the metal surfaces to analytes of large size. These etched areas variously increase the sensitivity of electrochemical detection devices to low concentrations of analyte, improve the plug flow characteristic of the channel, and allow additional discrimination of the colloidal particles during cyclic voltammetry.

  16. Selectively-etched nanochannel electrophoretic and electrochemical devices

    DOEpatents

    Surh, Michael P.; Wilson, William D.; Barbee, Jr., Troy W.; Lane, Stephen M.

    2006-06-27

    Nanochannel electrophoretic and electrochemical devices having selectively-etched nanolaminates located in the fluid transport channel. The normally flat surfaces of the nanolaminate having exposed conductive (metal) stripes are selectively-etched to form trenches and baffles. The modifications of the prior utilized flat exposed surfaces increase the amount of exposed metal to facilitate electrochemical redox reaction or control the exposure of the metal surfaces to analytes of large size. These etched areas variously increase the sensitivity of electrochemical detection devices to low concentrations of analyte, improve the plug flow characteristic of the channel, and allow additional discrimination of the colloidal particles during cyclic voltammetry.

  17. Protein electrophoretic migration data from custom and commercial gradient gels.

    PubMed

    Miller, Andrew J; Roman, Brandon; Norstrom, Eric M

    2016-12-01

    This paper presents data related to the article "A method for easily customizable gradient gel electrophoresis" (A.J. Miller, B. Roman, E.M. Norstrom, 2016) [1]. Data is presented on the rate of electrophoretic migration of proteins in both hand-poured and commercially acquired acrylamide gradient gels. For each gel, migration of 9 polypeptides of various masses was measured upon completion of gel electrophoresis. Data are presented on the migration of proteins within separate lanes of the same gel as well as migration rates from multiple gels. PMID:27622203

  18. Trans-synaptic zinc mobilization improves social interaction in two mouse models of autism through NMDAR activation

    PubMed Central

    Lee, Eun-Jae; Lee, Hyejin; Huang, Tzyy-Nan; Chung, Changuk; Shin, Wangyong; Kim, Kyungdeok; Koh, Jae-Young; Hsueh, Yi-Ping; Kim, Eunjoon

    2015-01-01

    Genetic aspects of autism spectrum disorders (ASDs) have recently been extensively explored, but environmental influences that affect ASDs have received considerably less attention. Zinc (Zn) is a nutritional factor implicated in ASDs, but evidence for a strong association and linking mechanism is largely lacking. Here we report that trans-synaptic Zn mobilization rapidly rescues social interaction in two independent mouse models of ASD. In mice lacking Shank2, an excitatory postsynaptic scaffolding protein, postsynaptic Zn elevation induced by clioquinol (a Zn chelator and ionophore) improves social interaction. Postsynaptic Zn is mainly derived from presynaptic pools and activates NMDA receptors (NMDARs) through postsynaptic activation of the tyrosine kinase Src. Clioquinol also improves social interaction in mice haploinsufficient for the transcription factor Tbr1, which accompanies NMDAR activation in the amygdala. These results suggest that trans-synaptic Zn mobilization induced by clioquinol rescues social deficits in mouse models of ASD through postsynaptic Src and NMDAR activation. PMID:25981743

  19. Trans-synaptic zinc mobilization improves social interaction in two mouse models of autism through NMDAR activation.

    PubMed

    Lee, Eun-Jae; Lee, Hyejin; Huang, Tzyy-Nan; Chung, Changuk; Shin, Wangyong; Kim, Kyungdeok; Koh, Jae-Young; Hsueh, Yi-Ping; Kim, Eunjoon

    2015-01-01

    Genetic aspects of autism spectrum disorders (ASDs) have recently been extensively explored, but environmental influences that affect ASDs have received considerably less attention. Zinc (Zn) is a nutritional factor implicated in ASDs, but evidence for a strong association and linking mechanism is largely lacking. Here we report that trans-synaptic Zn mobilization rapidly rescues social interaction in two independent mouse models of ASD. In mice lacking Shank2, an excitatory postsynaptic scaffolding protein, postsynaptic Zn elevation induced by clioquinol (a Zn chelator and ionophore) improves social interaction. Postsynaptic Zn is mainly derived from presynaptic pools and activates NMDA receptors (NMDARs) through postsynaptic activation of the tyrosine kinase Src. Clioquinol also improves social interaction in mice haploinsufficient for the transcription factor Tbr1, which accompanies NMDAR activation in the amygdala. These results suggest that trans-synaptic Zn mobilization induced by clioquinol rescues social deficits in mouse models of ASD through postsynaptic Src and NMDAR activation.

  20. Electrophoretic analysis and separation of single-walled carbon nanotubes and metallic nanoparticles

    NASA Astrophysics Data System (ADS)

    Xu, Xiaoyou

    Electrophoresis has been widely used in biological science but has barely applied to nanomaterials. This study is to demonstrate the applications of electrophoresis to separation and analysis of nanomaterials based on size and shape. In an effort to purify arc-discharge single-walled carbon nanotubes (SWNTs), we developed a procedure to separate larger graphite-related materials from stable crude nanotubes suspension, which was subjected to electrophoretic separation in glass bead matrix and agarose gel. Three important components were well separated: purified SWNTs, short tubule carbon species, and fluorescent fragments. For the first time, electrophoresis has been successfully used to purify arc-discharge SWNTs. Moreover, the two classes of new nanomaterials: short tubule carbon and fluorescent fragments promise to be useful in their own right. The electrophoretic technique was extended to the separation of gold nanoparticles. First, column electrophoresis was demonstrated to separate nanospheres based on size. Next crude nanospheres were electrophoretically purified. The standard deviation of crude sample of 20% was narrowed to 3--4% of purified sample, indicative of substantial improvement in size distribution. Finally, the crude gold nanorod sample was separated into three components based on shape: spheres, platelets, and rods. Gel electrophoresis has demonstrated much higher resolution than conventional methods: multi-step centrifugation, size exclusion chromatography, etc. In spite of the fact that SERS activity is intimately associated with the size and shape of nanoparticles, there are rare reports on how to find the size and shape of nanoparticles with highest SERS activity. To achieve this goal, we have designed a procedure. First, crude silver nanoparticles with wide distribution in size and shape was synthesized and functionalized. Then gel electrophoresis was used to separate the nanoparticles into different colorful bands and each of them may

  1. Electrophoretic deposition and mechanistic studies of nano-Al/CuO thermites

    NASA Astrophysics Data System (ADS)

    Sullivan, K. T.; Kuntz, J. D.; Gash, A. E.

    2012-07-01

    Electrophoretic deposition was used to deposit thin films (˜10-200 μm) of nano-aluminum/copper oxide thermites, with a density of 29% the theoretical maximum. The reaction propagation velocity was examined using fine-patterned electrodes (0.25 × 20 mm), and the optimum velocity was found to correspond to a fuel-rich equivalence ratio of 1.7. This value did not correlate with the calculated maximum in gas production or temperature, and it is suggested that it is a result of enhanced condensed-phase transport, which is speculated to increase for fuel-rich conditions. A ˜25% drop in propagation velocity occurred above an equivalence ratio of 2.0, where Al2O3 is predicted to undergo a phase change from liquid to solid. This is expected to hinder the kinetics by decreasing the mobility of condensed-phase reacting species. The effect of film thickness on propagation velocity was investigated, using the optimum equivalence ratio. The velocity was seen to exhibit a two-plateau behavior, with one plateau between 13 and 50 μm film thickness, and the other above ˜120 μm. The latter had nearly an order of magnitude faster velocity than the former, 36 m/s vs. 4 m/s, respectively. For film thicknesses in the 50-120 μm range, a linear transitional regime was observed. Images from the combustion studies showed an increase in forward-transported particles as the film thickness increased, along with more turbulent behavior of the flame. It was suggested that the two-plateau behavior indicated a shift in the energy transport mechanism. While nanocomposite thermites have been traditionally thought to exhibit convective energy transport, we find in this work that particle advection may also be important. The velocity of particles ejected through a thin slit mounted above a thermite strip was measured, and was found to be even faster (˜2-3×) than the flame propagation velocity. The morphology of captured particles was examined with an electron microscope, and indicated that

  2. Aspirin's Active Metabolite Salicylic Acid Targets High Mobility Group Box 1 to Modulate Inflammatory Responses.

    PubMed

    Choi, Hyong Woo; Tian, Miaoying; Song, Fei; Venereau, Emilie; Preti, Alessandro; Park, Sang-Wook; Hamilton, Keith; Swapna, G V T; Manohar, Murli; Moreau, Magali; Agresti, Alessandra; Gorzanelli, Andrea; De Marchis, Francesco; Wang, Huang; Antonyak, Marc; Micikas, Robert J; Gentile, Daniel R; Cerione, Richard A; Schroeder, Frank C; Montelione, Gaetano T; Bianchi, Marco E; Klessig, Daniel F

    2015-01-01

    Salicylic acid (SA) and its derivatives have been used for millennia to reduce pain, fever and inflammation. In addition, prophylactic use of acetylsalicylic acid, commonly known as aspirin, reduces the risk of heart attack, stroke and certain cancers. Because aspirin is rapidly de-acetylated by esterases in human plasma, much of aspirin's bioactivity can be attributed to its primary metabolite, SA. Here we demonstrate that human high mobility group box 1 (HMGB1) is a novel SA-binding protein. SA-binding sites on HMGB1 were identified in the HMG-box domains by nuclear magnetic resonance (NMR) spectroscopic studies and confirmed by mutational analysis. Extracellular HMGB1 is a damage-associated molecular pattern molecule (DAMP), with multiple redox states. SA suppresses both the chemoattractant activity of fully reduced HMGB1 and the increased expression of proinflammatory cytokine genes and cyclooxygenase 2 (COX-2) induced by disulfide HMGB1. Natural and synthetic SA derivatives with greater potency for inhibition of HMGB1 were identified, providing proof-of-concept that new molecules with high efficacy against sterile inflammation are attainable. An HMGB1 protein mutated in one of the SA-binding sites identified by NMR chemical shift perturbation studies retained chemoattractant activity, but lost binding of and inhibition by SA and its derivatives, thereby firmly establishing that SA binding to HMGB1 directly suppresses its proinflammatory activities. Identification of HMGB1 as a pharmacological target of SA/aspirin provides new insights into the mechanisms of action of one of the world's longest and most used natural and synthetic drugs. It may also provide an explanation for the protective effects of low-dose aspirin usage. PMID:26101955

  3. Aspirin's Active Metabolite Salicylic Acid Targets High Mobility Group Box 1 to Modulate Inflammatory Responses.

    PubMed

    Choi, Hyong Woo; Tian, Miaoying; Song, Fei; Venereau, Emilie; Preti, Alessandro; Park, Sang-Wook; Hamilton, Keith; Swapna, G V T; Manohar, Murli; Moreau, Magali; Agresti, Alessandra; Gorzanelli, Andrea; De Marchis, Francesco; Wang, Huang; Antonyak, Marc; Micikas, Robert J; Gentile, Daniel R; Cerione, Richard A; Schroeder, Frank C; Montelione, Gaetano T; Bianchi, Marco E; Klessig, Daniel F

    2015-06-18

    Salicylic acid (SA) and its derivatives have been used for millennia to reduce pain, fever and inflammation. In addition, prophylactic use of acetylsalicylic acid, commonly known as aspirin, reduces the risk of heart attack, stroke and certain cancers. Because aspirin is rapidly de-acetylated by esterases in human plasma, much of aspirin's bioactivity can be attributed to its primary metabolite, SA. Here we demonstrate that human high mobility group box 1 (HMGB1) is a novel SA-binding protein. SA-binding sites on HMGB1 were identified in the HMG-box domains by nuclear magnetic resonance (NMR) spectroscopic studies and confirmed by mutational analysis. Extracellular HMGB1 is a damage-associated molecular pattern molecule (DAMP), with multiple redox states. SA suppresses both the chemoattractant activity of fully reduced HMGB1 and the increased expression of proinflammatory cytokine genes and cyclooxygenase 2 (COX-2) induced by disulfide HMGB1. Natural and synthetic SA derivatives with greater potency for inhibition of HMGB1 were identified, providing proof-of-concept that new molecules with high efficacy against sterile inflammation are attainable. An HMGB1 protein mutated in one of the SA-binding sites identified by NMR chemical shift perturbation studies retained chemoattractant activity, but lost binding of and inhibition by SA and its derivatives, thereby firmly establishing that SA binding to HMGB1 directly suppresses its proinflammatory activities. Identification of HMGB1 as a pharmacological target of SA/aspirin provides new insights into the mechanisms of action of one of the world's longest and most used natural and synthetic drugs. It may also provide an explanation for the protective effects of low-dose aspirin usage.

  4. Development of the Self-Powered Extravehicular Mobility Unit Extravehicular Activity Data Recorder

    NASA Technical Reports Server (NTRS)

    Bernard, Craig; Hill, Terry R.; Murray, Sean; Wichowski, Robert; Rosenbush, David

    2012-01-01

    The Self-Powered Extravehicular Mobility Unit (EMU) Extravehicular Activity (EVA) Data Recorder (SPEEDR) is a field-programmable gate array (FPGA)-based device designed to collect high-rate EMU Primary Life Support Subsystem (PLSS) data for download at a later time. During EVA, the existing EMU PLSS data downlink capability is one data packet every 2 minutes and is subject to bad packets or loss of signal. Higher-rate PLSS data is generated by the Enhanced Caution and Warning System but is not normally captured or distributed. Access to higher-rate data will increase the capability of EMU anomaly resolution team to pinpoint issues remotely, saving crew time by reducing required call-down Q&A and on-orbit diagnostic activities. With no Space Shuttle flights post Fiscal Year 2011 (FY11), and potentially limited down-mass capability, the ISS crew and ground support personnel will have to be capable of on-orbit operations to maintain, diagnose, repair, and return to service EMU hardware, possibly through 2028. Collecting high-rate EMU PLSS data during both intravehicular activity (IVA) and EVA operations will provide trending analysis for life extension and/or predictive performance. The SPEEDR concept has generated interest as a tool/technology that could be used for other International Space Station subsystems or future exploration-class space suits where hardware reliability/availability is critical and low/variable bandwidth may require store then forward methodology. Preliminary work in FY11 produced a functional prototype consisting of an FPGA evaluation board, custom memory/interface circuit board, and custom software. The SPEEDR concept includes a stand-alone battery that is recharged by a computer Universal Serial Bus (USB) port while data are being downloaded.

  5. How can the curation of hands-on STEM activities power successful mobile apps and websites?

    NASA Astrophysics Data System (ADS)

    Porcello, D.; Peticolas, L. M.; Schwerin, T. G.

    2015-12-01

    The Lawrence Hall of Science (LHS) is University of California, Berkeley's public science center. Over the last decade, the Center for Technology Innovation at LHS has partnered with many institutions to establish a strong track record of developing successful technology solutions to support STEM teaching and learning within informal environments. Curation by subject-matter experts has been at the heart of many educational technology products from LHS and its partners that are directed at educators and families. This work includes: (1) popular digital libraries for inquiry-based activities at Howtosmile.org (NSF DRL #0735007) and NASA Earth and Space science education resources at NASAwavelength.org; and novel mobile apps like DIY Sun Science (NASA NNX10AE05G) and DIY Human Body (NIH 5R25OD010543) designed to scaffold exploration of STEM phenomena at home. Both NASA Wavelength and DIY Sun Science arose out of long-term collaborations with the Space Sciences Laboratory at UC Berkeley, Institute for Global Environmental Strategies (IGES), and other NASA-funded organizations, in partnership with NASA through cooperative agreements. This session will review the development, formative evaluation, and usage metrics for these two Earth and Space science-themed educational technology products directly relevant to the AGU community. Questions reviewed by presenters will include: What makes a good hands-on activity, and what essential information do educators depend on when searching for programming additions? What content and connections do families need to explore hands-on activities? How can technology help incorporate educational standards into the discovery process for learning experiences online? How do all these components drive the design and user experience of websites and apps that showcase STEM content?

  6. Simulated null-gravity environments as applied to electrophoretic separations of biological species

    NASA Technical Reports Server (NTRS)

    Giannovario, J. A.; Griffin, R. N.

    1978-01-01

    The scale-up of electrophoretic separations to provide preparative quantities of materials has been hampered by gravity induced convection and sedimentation. The separation of biologically important species may be significantly enhanced by electrophoretic space processing. Simple demonstrations on past space flights have proven some principles. Several techniques have been evolved to study electrophoretic separations where the effects of gravity have been nullified or significantly reduced. These techniques employ mechanical design, density gradients and computer modeling. Utilization of these techniques for ground based studies will yield clues as to which biological species can be considered prime candidates for electrophoretic processing in zero-G.

  7. Electrophoretic deposition of titanium dioxide films on copper in aqueous media.

    PubMed

    Laamari, M; Ben Youssef, A; Bousselmi, L

    2016-01-01

    Electrophoretic deposition was used to produce titanium dioxide (TiO2) nanostructured films on copper substrate in aqueous media for photocatalytic application. Polyvinyl pyrrolidone (PVP) with a weight rate from 0 to 15% was added to TiO2 P25 suspension in order to enhance film adhesion. The films were characterized by X-ray diffraction, optical microscopy, contact angle measurement, nanoindentation, scratch test and photoluminescence. The photocatalytic activity of the films was tested with amido black 10B under UV irradiation. The results indicated that the morphology and the mechanical properties of films depended on the added PVP amount. Scratch test showed that adhesion strength rose with increased PVP amount. The photocatalytic activity indicated that TiO2 film synthesized with 13% PVP had the highest efficiency. PMID:27438247

  8. Restricting mobility of Gsalpha relative to the beta2-adrenoceptor enhances adenylate cyclase activity by reducing Gsalpha GTPase activity.

    PubMed Central

    Wenzel-Seifert, K; Lee, T W; Seifert, R; Kobilka, B K

    1998-01-01

    The beta2-adrenoceptor (beta2AR) activates the G-protein Gsalpha to stimulate adenylate cyclase (AC). Fusion of the beta2AR C-terminus to the N-terminus of Gsalpha (producing beta2ARGsalpha) markedly increases the efficiency of receptor/G-protein coupling compared with the non-fused state. This increase in coupling efficiency can be attributed to the physical proximity of receptor and G-protein. To determine the optimal length for the tether between receptor and G-protein we constructed fusion proteins from which 26 [beta2AR(Delta26)Gsalpha] or 70 [beta2AR(Delta70)Gsalpha] residues of the beta2AR C-terminus had been deleted and compared the properties of these fusion proteins with the previously described beta2ARGsalpha. Compared with beta2ARGsalpha, basal and agonist-stimulated GTP hydrolysis was markedly decreased in beta2AR(Delta70)Gsalpha, whereas the effect of the deletion on binding of guanosine 5'-[gamma-thio]triphosphate (GTP[S]) was relatively small. Surprisingly, deletions did not alter the efficiency of coupling of the beta2AR to Gsalpha as assessed by GTP[S]-sensitive high-affinity agonist binding. Moreover, basal and ligand-regulated AC activities in membranes expressing beta2AR(Delta70)Gsalpha and beta2AR(Delta26)Gsalpha were higher than in membranes expressing beta2ARGsalpha. These findings suggest that restricting the mobility of Gsalpha relative to the beta2AR results in a decrease in G-protein inactivation by GTP hydrolysis and thereby enhanced activation of AC. PMID:9729456

  9. High-mobility group box-1 induces vascular remodelling processes via c-Jun activation

    PubMed Central

    Zabini, Diana; Crnkovic, Slaven; Xu, Hui; Tscherner, Maria; Ghanim, Bahil; Klepetko, Walter; Olschewski, Andrea; Kwapiszewska, Grazyna; Marsh, Leigh M

    2015-01-01

    Extracellular high-mobility group box-1 (HMGB1) acts as a signalling molecule during inflammation, cell differentiation and angiogenesis. Increased abundance of HMGB1 is associated with several pathological disorders such as cancer, asthma and chronic obstructive pulmonary disease (COPD). In this study, we investigated the relevance of HMGB1 in the pathological remodelling present in patients with idiopathic pulmonary arterial hypertension (IPAH) and pulmonary hypertension (PH) associated with COPD. Remodelled vessels present in COPD with PH and IPAH lung samples were often surrounded by HMGB1-positive cells. Increased HMGB1 serum levels were detected in both patient populations compared to control samples. The effects of physiological HMGB1 concentrations were then examined on cellular responses in vitro. HMGB1 enhanced proliferation of pulmonary arterial smooth muscle cells (PASMC) and primary human arterial endothelial cells (PAEC). HMGB1 stimulated p38, extracellular signal-regulated kinase (ERK) and c-Jun N-terminal kinase (JNK) phosphorylation. Furthermore, activation of the downstream AP-1 complex proteins c-Fos and c-Jun was observed. Silencing of c-Jun ablated the HMGB1-induced proliferation in PASMC. Thus, an inflammatory component such as HMGB1 can contribute to PASMC and PAEC proliferation and therefore potentially to vascular remodelling and PH pathogenesis. PMID:25726846

  10. Design and Certification of the Extravehicular Activity Mobility Unit (EMU) Water Processing Jumper

    NASA Technical Reports Server (NTRS)

    Peterson, Laurie J.; Neumeyer, Derek J.; Lewis, John F.

    2006-01-01

    The Extravehicular Mobility Units (EMUs) onboard the International Space Station (ISS) experienced a failure due to cooling water contamination from biomass and corrosion byproducts forming solids around the EMU pump rotor. The coolant had no biocide and a low pH which induced biofilm growth and corrosion precipitates, respectively. NASA JSC was tasked with building hardware to clean the ionic, organic, and particulate load from the EMU coolant loop before and after Extravehicular Activity (EVAs). Based on a return sample of the EMU coolant loop, the chemical load was well understood, but there was not sufficient volume of the returned sample to analyze particulates. Through work with EMU specialists, chemists, (EVA) Mission Operations Directorate (MOD) representation, safety and mission assurance, astronaut crew, and team engineers, requirements were developed for the EMU Water Processing hardware (sometimes referred to as the Airlock Coolant Loop Recovery [A/L CLR] system). Those requirements ranged from the operable level of ionic, organic, and particulate load, interfaces to the EMU, maximum cycle time, operating pressure drop, flow rate, and temperature, leakage rates, and biocide levels for storage. Design work began in February 2005 and certification was completed in April 2005 to support a return to flight launch date of May 12, 2005. This paper will discuss the details of the design and certification of the EMU Water Processing hardware and its components

  11. Mobile Phone Apps to Promote Weight Loss and Increase Physical Activity: A Systematic Review and Meta-Analysis

    PubMed Central

    Ferré-Grau, Carme; Montaña-Carreras, Xavier

    2015-01-01

    Background To our knowledge, no meta-analysis to date has assessed the efficacy of mobile phone apps to promote weight loss and increase physical activity. Objective To perform a systematic review and meta-analysis of studies to compare the efficacy of mobile phone apps compared with other approaches to promote weight loss and increase physical activity. Methods We conducted a systematic review and meta-analysis of relevant studies identified by a search of PubMed, the Cumulative Index to Nursing and Allied Health Literature (CINAHL), and Scopus from their inception through to August 2015. Two members of the study team (EG-F, GF-M) independently screened studies for inclusion criteria and extracted data. We included all controlled studies that assessed a mobile phone app intervention with weight-related health measures (ie, body weight, body mass index, or waist circumference) or physical activity outcomes. Net change estimates comparing the intervention group with the control group were pooled across studies using random-effects models. Results We included 12 articles in this systematic review and meta-analysis. Compared with the control group, use of a mobile phone app was associated with significant changes in body weight (kg) and body mass index (kg/m2) of -1.04 kg (95% CI -1.75 to -0.34; I2 = 41%) and -0.43 kg/m2 (95% CI -0.74 to -0.13; I2 = 50%), respectively. Moreover, a nonsignificant difference in physical activity was observed between the two groups (standardized mean difference 0.40, 95% CI -0.07 to 0.87; I2 = 93%). These findings were remarkably robust in the sensitivity analysis. No publication bias was shown. Conclusions Evidence from this study shows that mobile phone app-based interventions may be useful tools for weight loss. PMID:26554314

  12. Electrophoretic motion of ideally polarizable particles in a microchannel.

    PubMed

    Wu, Zhemin; Gao, Yandong; Li, Dongqing

    2009-03-01

    The induced-charge electrophoretic (ICEP) motion of ideally polarizable particles in a microchannel is numerically studied in this paper. A complete 3-D multi-physics model is set up to simulate the transient ICEP motion of spherical ideally polarizable particles in a microchannel. The study shows that a non-uniform distribution of induced surface charge occurs when an ideally polarizable particle is immersed in an externally applied electric field, resulting in a varying slipping (EOF) velocity along the particle's surface and hence producing micro vortexes in the liquid. The numerical results verify that the steady-state ICEP velocity of an ideally polarizable particle does not differ from the electrophoretic velocity of a non-conducting particle, although the flow field near the particle does. A strong wall-repelling effect of ICEP is found when the polarizable particle is placed close to the channel wall. This is due to the lifting effect generated from the interaction between the induced micro vortexes and the channel wall and depends on the electric field and the particle size. The wall effects on ICEP motion can be used for focusing particles and for separation of particle by density. PMID:19197897

  13. Electrophoretic analysis of PEGylated hemoglobin-based blood substitutes.

    PubMed

    Ronda, Luca; Pioselli, Barbara; Bruno, Stefano; Faggiano, Serena; Mozzarelli, Andrea

    2011-01-01

    Polyethylene glycol (PEG)-conjugated hemoglobins, a novel class of blood substitutes, were investigated by a combination of native and denaturing one- and two-dimensional polyacrylamide gel electrophoresis (PAGE) coupled with the microspectrophotometric characterization of single bands and the functional analysis of electrophoretically separated fractions. For these intrinsically heterogeneous products, the molecular mass, the size distribution, and the degree of PEGylation are strictly correlated to their side effects and, therefore, are crucial pieces of information to evaluate their safety and efficacy. The PEGylation pattern was shown to strongly depend on the quaternary conformation of hemoglobin during the reaction, and the degree of conjugation was shown to correlate with the oxygen binding properties of the individual electrophoretically separated fractions. Moreover, small but not negligible fractions of underivatized tetramers, known to be responsible for serious side effects, were detected even in preparations with a high average degree of PEGylation. Overall, this approach might be exploited to characterize other products of protein PEGylation, an increasingly relevant technology for the optimization of the pharmacokinetic properties of protein-based drugs.

  14. Electrophoretic deposition of composite hydroxyapatite-chitosan coatings

    SciTech Connect

    Pang Xin; Zhitomirsky, Igor . E-mail: zhitom@mcmaster.ca

    2007-04-15

    Cathodic electrophoretic deposition has been utilized for the fabrication of composite hydroxyapatite-chitosan coatings on 316L stainless steel substrates. The addition of chitosan to the hydroxyapatite suspensions promoted the electrophoretic deposition of the hydroxyapatite nanoparticles and resulted in the formation of composite coatings. The obtained coatings were investigated by X-ray diffraction, thermogravimetric and differential thermal analysis, scanning and transmission electron microscopy, potentiodynamic polarization measurements, and electrochemical impedance spectroscopy. It was shown that the deposit composition can be changed by a variation of the chitosan or hydroxyapatite concentration in the solutions. Experimental conditions were developed for the fabrication of hydroxyapatite-chitosan nanocomposites containing 40.9-89.8 wt.% hydroxyapatite. The method enabled the formation of adherent and uniform coatings of thicknesses up to 60 {mu}m. X-ray studies revealed that the preferred orientation of the hydroxyapatite nanoparticles in the chitosan matrix increases with decreasing hydroxyapatite content in the composite coatings. The obtained coatings provided the corrosion protection for the 316L stainless steel substrates00.

  15. Recent innovations in protein separation on microchips by electrophoretic methods.

    PubMed

    Peng, Youyuan; Pallandre, Antoine; Tran, N Thuy; Taverna, Myriam

    2008-01-01

    Microchips for analytical purposes have attracted great attention over the last 20 years. In the present review, we focus on the most recent development of microchips for electrophoretic separation of proteins. This review starts with a short recalling about the microchips covering the basic microchip layout for CE and the commercial chips and microchip platforms. A short paragraph is dedicated to the surface treatment of microchips, which is of paramount importance in protein analysis. One section is dedicated to on-line sample pretreatment in microchips and summarizes different strategies to pre-concentrate or to purify proteins from complex matrixes. Most of the common modes used for CE of proteins have already been adapted to the chip format, while multidimensional approaches are still in progress. The different routes to achieve detection in microchip are also presented with a special attention to derivatization or labeling of proteins. Finally, several recent applications are mentioned. They highlight the great potential of electrophoretic separations of proteins in numerous fields such as biological, pharmaceutical or agricultural and food analysis. A bibliography with 151 references is provided covering papers published from 2000 to the early 2007.

  16. Electrophoretic deposition of zinc-substituted hydroxyapatite coatings.

    PubMed

    Sun, Guangfei; Ma, Jun; Zhang, Shengmin

    2014-06-01

    Zinc-substituted hydroxyapatite nanoparticles synthesized by the co-precipitation method were used to coat stainless steel plates by electrophoretic deposition in n-butanol with triethanolamine as a dispersant. The effect of zinc concentration in the synthesis on the morphology and microstructure of coatings was investigated. It is found that the deposition current densities significantly increase with the increasing zinc concentration. The zinc-substituted hydroxyapatite coatings were analyzed by X-ray diffraction, scanning electron microscopy and Fourier transform infrared spectroscopy. It is inferred that hydroxyapatite and triethanolamine predominate in the chemical composition of coatings. With the increasing Zn/Ca ratios, the contents of triethanolamine decrease in the final products. The triethanolamine can be burnt out by heat treatment. The tests of adhesive strength have confirmed good adhesion between the coatings and substrates. The formation of new apatite layer on the coatings has been observed after 7days of immersion in a simulated body fluid. In summary, the results show that dense, uniform zinc-substituted hydroxyapatite coatings are obtained by electrophoretic deposition when the Zn/Ca ratio reaches 5%.

  17. What kinds of website and mobile phone-delivered physical activity and nutrition interventions do middle-aged men want?

    PubMed

    Vandelanotte, Corneel; Caperchione, Cristina M; Ellison, Marcus; George, Emma S; Maeder, Anthony; Kolt, Gregory S; Duncan, Mitch J; Karunanithi, Mohanraj; Noakes, Manny; Hooker, Cindy; Viljoen, Pierre; Mummery, W Kerry

    2013-01-01

    Within a health context, men in Western societies are a hard-to-reach population who experience higher rates of chronic disease compared with women. Innovative technology-based interventions that specifically target men are needed; however, little is known about how these should be developed for this group. This study aimed to examine opinions and perceptions regarding the use of Internet and mobile phones to improve physical activity and nutrition behaviors for middle-aged men. The authors conducted 6 focus groups (n = 30) in Queensland, Australia. Their analyses identified 6 themes: (a) Internet experience, (b) website characteristics, (c) Web 2.0 applications, (d) website features, (e) self-monitoring, and (f) mobile phones as delivery method. The outcomes indicate that men support the use of the Internet to improve and self-monitor physical activity and dietary behaviors on the condition that the website-delivered interventions are quick and easy to use, because commitment levels to engage in online tasks are low. Participants also indicated that they were reluctant to use normal mobile phones to change health behaviors, although smartphones were perceived to be more acceptable. This pilot study suggests that there are viable avenues to engage middle-aged men in Internet- or in mobile-delivered health interventions. This study also suggests that to be successful, these interventions need to be tailor-made especially for men, with an emphasis on usability and convenience. A wider quantitative study would bring further support to these findings.

  18. Age-dependent changes in extracellular proteins, aminopeptidase and proteinase activities in Frankia isolate BR.

    PubMed

    Müller, A; Benoist, P; Diem, H G; Schwencke, J

    1991-12-01

    To investigate protein secretion by the nitrogen-fixing actinomycete Frankia isolate BR, we designed a rapid DEAE adsorption, salt elution and Biogel P6DG desalination method to concentrate protein from the growth medium. Secreted proteins reached a maximum concentration (5.6 gm l-1) in the medium at growth arrest. Analysis by SDS-PAGE detected up to 63 extracellular polypeptides when Frankia cells were grown under stirred conditions in BAP medium supplemented with phosphatidylcholine and MES buffer and 65 proteins in stirred BAP media alone. The pattern of extracellular polypeptides changed during growth. Several extracellular proteolytic activities were detected and compared with intracellular ones. The substrate specificity of the extracellular and intracellular aminopeptidase activities were the same. Also, the electrophoretic migration patterns of secreted and intracellular aminopeptidases could not be distinguished. Secretion of the proline-specific aminopeptidase FAP proteinase (PF) were secreted: 10 had the same electrophoretic mobility as their intracellular counterparts after SDS-gelatine-PAGE while five (PF - 39.5, PF - 38.5, PF - 36.5, PF - 25.5 and PF - 20.5 kDa) had a different electrophoretic mobility and, therefore, appeared to be exclusively extracellular. At least seven extracellular proteinases appeared to increase coordinately in activity shortly before growth arrest.

  19. Relationship of stride activity and participation in mobility-based life habits among children with cerebral palsy

    PubMed Central

    Bjornson, Kristie F.; Zhou, Chuan; Stevenson, Richard D.; Christakis, Dimitri

    2014-01-01

    Objective To date walking outcomes in cerebral palsy (CP) have been capacity-based (what a child does in structured setting). Physical activity performance (what a child really does in daily life) has been documented to influence the relationship of capacity-based gross motor measures to participation.(1) This study examines the relationship between walking performance and participation in mobility-related habits of daily life in children with CP. Design Cross-sectional prospective cohort study. Setting Regional pediatric specialty care centers Participants A cohort of 128 ambulatory children with CP ages 2–9 yrs, 41% female, and 49% having hemiplegia participated. Interventions Not Applicable. Main Outcome Measures Walking performance was quantified from a 5-day sample of StepWatch accelerometry data. Stride activity was summarized through the outcomes of average total strides/day (independent of intensity) and average number of strides/day at > 30 strides/minute (marker of intensity). Mobility-based participation was assessed by the Life Habits (Life-H) categories of Personal Care, Housing, Mobility, and Recreation. Regression models were developed controlling for gender, age, cognition, communication, pain, and body composition. Results Average total strides/day was positively associated with the Personal Care, Housing, Mobility, and Recreation Life-H categories (β = .34 to.41, p <.001). Average number of strides > 30 stride/min/day was associated with all categories (β = .54 to.60, p < .001). Conclusions Accelerometry-based walking activity performance is significantly associated with levels of participation in mobility-based life habits for ambulatory children with CP. Evaluation of other factors and the direction of relationships within the ICF is warranted to inform rehabilitation strategies. PMID:24231402

  20. Microchannel gel electrophoretic separation systems and methods for preparing and using

    DOEpatents

    Herr, Amy E; Singh, Anup K; Throckmorton, Daniel J

    2015-02-24

    A micro-analytical platform for performing electrophoresis-based immunoassays was developed by integrating photopolymerized cross-linked polyacrylamide gels within a microfluidic device. The microfluidic immunoassays are performed by gel electrophoretic separation and quantifying analyte concentration based upon conventional polyacrylamide gel electrophoresis (PAGE). To retain biological activity of proteins and maintain intact immune complexes, native PAGE conditions were employed. Both direct (non-competitive) and competitive immunoassay formats are demonstrated in microchips for detecting toxins and biomarkers (cytokines, c-reactive protein) in bodily fluids (serum, saliva, oral fluids). Further, a description of gradient gels fabrication is included, in an effort to describe methods we have developed for further optimization of on-chip PAGE immunoassays. The described chip-based PAGE immunoassay method enables immunoassays that are fast (minutes) and require very small amounts of sample (less than a few microliters). Use of microfabricated chips as a platform enables integration, parallel assays, automation and development of portable devices.

  1. Microchannel gel electrophoretic separation systems and methods for preparing and using

    DOEpatents

    Herr, Amy; Singh, Anup K; Throckmorton, Daniel J

    2013-09-03

    A micro-analytical platform for performing electrophoresis-based immunoassays was developed by integrating photopolymerized cross-linked polyacrylamide gels within a microfluidic device. The microfluidic immunoassays are performed by gel electrophoretic separation and quantifying analyte concentration based upon conventional polyacrylamide gel electrophoresis (PAGE). To retain biological activity of proteins and maintain intact immune complexes, native PAGE conditions were employed. Both direct (non-competitive) and competitive immunoassay formats are demonstrated in microchips for detecting toxins and biomarkers (cytokines, c-reactive protein) in bodily fluids (serum, saliva, oral fluids). Further, a description of gradient gels fabrication is included, in an effort to describe methods we have developed for further optimization of on-chip PAGE immunoassays. The described chip-based PAGE immunoassay method enables immunoassays that are fast (minutes) and require very small amounts of sample (less than a few microliters). Use of microfabricated chips as a platform enables integration, parallel assays, automation and development of portable devices.

  2. Electrophoretically deposited multiwalled carbon nanotube based amperometric genosensor for E.coli detection

    NASA Astrophysics Data System (ADS)

    Bhardwaj, Hema; Solanki, Shipra; Sumana, Gajjala

    2016-04-01

    This work reports on a sensitive and selective genosensor fabrication method for Escherichia coli (E.coli) detection. The functionalized multiwalled carbon nanotubes (MWCNT) synthesized via chemical vapour deposition have been deposited electrophoretically onto indium tin oxide coated glass surface and have been utilized as matrices for the covalent immobilization of E.coli specific probe oligonucleotide that was identified from the 16s rRNA coding region of the E.coli genome. This fabricated functionalized MWCNT based platform sought to provide improved fundamental characteristics to electrode interface in terms of electro-active surface area and diffusion coefficient. Electrochemical cyclic voltammetry revealed that this genosensor exhibits a linear response to complementary DNA in the concentration range of 10-7 to 10-12 M with a detection limit of 1×10-12 M.

  3. Demonstrating Electrophoretic Separation in a Straight Paper Channel Delimited by a Hydrophobic Wax Barrier

    ERIC Educational Resources Information Center

    Xu, Chunxiu; Lin, Wanqi; Cai, Longfei

    2016-01-01

    A demonstration is described of electrophoretic separation of carmine and sunset yellow with a paper-based device. The channel in the paper device was fabricated by hand with a wax pen. Electrophoretic separation of carmine and sunset yellow was achieved within a few minutes by applying potential on the channel using a simple and inexpensive power…

  4. Mobility of a gas-pressurized elastic glove for extravehicular activity

    NASA Astrophysics Data System (ADS)

    Tanaka, Kunihiko; Abe, Chikara; Iwata, Chihiro; Yamagata, Kenji; Murakami, Naoko; Tanaka, Masao; Tanaka, Nobuyuki; Morita, Hironobu

    2010-04-01

    Usability of a gas-pressurized elastic glove for extravehicular activity (EVA) was evaluated by comparing its performance with that of a non-elastic glove like that in the current EVA suit. The right hands of eight healthy volunteers were studied in a chamber. The bare hand at normal ambient pressure, and at -220 mmHg of the chamber pressure (producing the same pressure differential as the current US EVA suit) with each of the gloves. No significant difference in cutaneous blood flow or skin temperature was observed between the gloves. Range of motion (ROM) in the proximal interphalangeal joint of the middle finger with the elastic glove (87.4±4.9°) was significantly wider than that with the non-elastic glove (70.6±2.3°), but the surface electromyography (EMG) amplitude during flexion with the elastic glove was significantly smaller than that with the non-elastic glove (29.3±2.7 mV vs. 46.7±2.3 mV for elastic and non-elastic gloves, respectively). The elastic glove also allowed smaller reduction in grip strength and longer endurance time than the non-elastic glove (-44.3±6.0% vs. -59.4±1.5% from the bare hand grip strength, 26.3±5.7% vs. 10.9±3.1% of the bare hand endurance time, for elastic and non-elastic glove, respectively). The static effects of non-elastic and elastic gloves are similar, but the mobility of the elastic glove is better than that of the non-elastic glove like the one used in the current EVA suit.

  5. Ionic liquids in chromatographic and electrophoretic techniques: toward additional improvements in the separation of natural compounds

    PubMed Central

    Freire, Carmen S. R.; Coutinho, João A. P.; Silvestre, Armando J. D.; Freire, Mara G.

    2016-01-01

    Due to their unique properties, in recent years, ionic liquids (ILs) have been largely investigated in the field of analytical chemistry. Particularly during the last sixteen years, they have been successfully applied in the chromatographic and electrophoretic analysis of value-added compounds extracted from biomass. Considering the growing interest in the use of ILs in this field, this critical review provides a comprehensive overview on the improvements achieved using ILs as constituents of mobile or stationary phases in analytical techniques, namely in capillary electrophoresis and its different modes, in high performance liquid chromatography, and in gas chromatography, for the separation and analysis of natural compounds. The impact of the IL chemical structure and the influence of secondary parameters, such as the IL concentration, temperature, pH, voltage and analysis time (when applied), are also critically addressed regarding the achieved separation improvements. Major conclusions on the role of ILs in the separation mechanisms and the performance of these techniques in terms of efficiency, resolution and selectivity are provided. Based on a critical analysis of all published results, some target-oriented ILs are suggested. Finally, current drawbacks and future challenges in the field are highlighted. In particular, the design and use of more benign and effective ILs as well as the development of integrated (and thus more sustainable) extraction–separation processes using IL aqueous solutions are suggested within a green chemistry perspective. PMID:27667965

  6. Electrophoretic Transport of Na(+) and K(+) Ions Within Cyclic Peptide Nanotubes.

    PubMed

    Carvajal-Diaz, Jennifer A; Cagin, Tahir

    2016-08-18

    One of the most important applications of cyclic peptide nanotubes (CPNTs) is their potential to be used as artificial ion channels. Natural ion channels are large and complex membrane proteins, which are very expensive, difficult to isolate, and sensible to denaturation; for this reason, artificial ion channels are an important alternative, as they can be produced by simple and inexpensive synthetic chemistry paths, allowing manipulation of properties and enhancement of ion selectivity properties. Artificial ion channels can be used as component in molecular sensors and novel therapeutic agents. Here, the electrophoretic transport of Na(+) and K(+) ions within cyclic peptide nanotubes is investigated by using molecular dynamic simulations. The effect of electric field in the stability of peptide nanotubes was studied by calculating the root mean square deviation curves. Results show that the stability for CPNTs decreases for higher electric fields. Selective transport of cations within the hydrophilic tubes was observed and the negative Cl(-) ions did not enter the peptide nanotubes during the simulation. Radial distribution functions were calculated to describe structural properties and coordination numbers and changes in the first and second hydration shell were observed for the transport of Na(+) and K(+) inside of cyclic peptide nanotubes. However, no effect on coordination number was observed. Diffusion coefficients were calculated from the mean square deviation curves and the Na(+) ion showed higher mobility than the K(+) ion as observed in equivalent experimental studies. The values for diffusion coefficients are comparable with previous calculations in protein channels of equivalent sizes. PMID:27448165

  7. Ionic liquids in chromatographic and electrophoretic techniques: toward additional improvements in the separation of natural compounds

    PubMed Central

    Freire, Carmen S. R.; Coutinho, João A. P.; Silvestre, Armando J. D.; Freire, Mara G.

    2016-01-01

    Due to their unique properties, in recent years, ionic liquids (ILs) have been largely investigated in the field of analytical chemistry. Particularly during the last sixteen years, they have been successfully applied in the chromatographic and electrophoretic analysis of value-added compounds extracted from biomass. Considering the growing interest in the use of ILs in this field, this critical review provides a comprehensive overview on the improvements achieved using ILs as constituents of mobile or stationary phases in analytical techniques, namely in capillary electrophoresis and its different modes, in high performance liquid chromatography, and in gas chromatography, for the separation and analysis of natural compounds. The impact of the IL chemical structure and the influence of secondary parameters, such as the IL concentration, temperature, pH, voltage and analysis time (when applied), are also critically addressed regarding the achieved separation improvements. Major conclusions on the role of ILs in the separation mechanisms and the performance of these techniques in terms of efficiency, resolution and selectivity are provided. Based on a critical analysis of all published results, some target-oriented ILs are suggested. Finally, current drawbacks and future challenges in the field are highlighted. In particular, the design and use of more benign and effective ILs as well as the development of integrated (and thus more sustainable) extraction–separation processes using IL aqueous solutions are suggested within a green chemistry perspective.

  8. Limitations in activities of daily living and instrumental activities of daily living capacity in a representative sample: disentangling dementia- and mobility-related effects.

    PubMed

    Wilms, Hans-Ulrich; Riedel-Heller, Steffi G; Angermeyer, Matthias C

    2007-01-01

    A representative sample of the Leipzig population aged 75 years and older showed 61.8% of the participants with relevant deficits in their capacity for independent living, according to a combined activities of daily living/instrumental activities of daily living (ADL/IADL) scale. The quantity and quality of care needed almost exponentially increases above 85 years of age. Looking at potential reasons for ADL/IADL limitations, 44% of variance in single ADL/IADL activities and 75% of the combined ADL/IADL sum score could come from a minimal set of predictor variables. Most important are dementia- or mobility-related declines, but living conditions also explain small but significant amounts of variance. These seem initially impressive, yet analyses showed about half the explained variances shared among the mobility and dementia indicators, limiting the use not only of ADL/IADL sum scores but of many single ADL/IADL items as well. Before deriving specific conclusions from variations in ADL/IADL instruments, one must note that the data suggest that interpretations of covariations--whether for health/mobility or dementia--are useful and substantial only if both indicators/predictors are verified. The information given captures the mobility- and dementia-related variance if ADL/IADL items, facilitating more specific scale developments.

  9. Chitosan-induced phospholipase A2 activation and arachidonic acid mobilization in P388D1 macrophages.

    PubMed

    Bianco, I D; Balsinde, J; Beltramo, D M; Castagna, L F; Landa, C A; Dennis, E A

    2000-01-28

    We have found that chitosan, a polysaccharide present in fungal cell walls, is able to activate macrophages for enhanced mobilization of arachidonic acid in a dose- and time-dependent manner. Studies aimed at identifying the intracellular effector(s) implicated in chitosan-induced arachidonate release revealed the involvement of the cytosolic Group IV phospholipase A2 (PLA2), as judged by the inhibitory effect of methyl arachidonoyl fluorophosphonate but not of bromoenol lactone. Interestingly, priming of the macrophages with lipopolysaccharide renders the cells more sensitive to a subsequent stimulation with chitosan, and this enhancement is totally blocked by the secretory PLA2 inhibitor 3-(3-acetamide)-1-benzyl-2-ethylindolyl-5-oxy-propanesulfonic acid (LY311727). Collectively, the results of this work establish chitosan as a novel macrophage-activating factor that elicits AA mobilization in P388D1 macrophages by a mechanism involving the participation of two distinct phospholipases A2. PMID:10682846

  10. Radiation does from medical in-vivo prompt gamma-ray activation using a mobile nuclear reactor.

    PubMed

    Chung, C; Chen, C P; Chang, P S

    1988-10-01

    A method of medical diagnosis of toxic elements, using a neutron beam from a mobile nuclear reactor to perform partial-body in-vivo prompt gamma-ray activation technique, has been developed. Both neutron and gamma-ray dose equivalents in an irradiated phantom and around medical researchers were measured and evaluated. Neutron flux at various kinetic energies was measured using an activation foil technique, and the neutron dose equivalents at tissues of risk inside the irradiated phantom were calculated by neutron transport code. Gamma-ray dose equivalents inside the irradiated phantom and around the nuclear reactor were measured by thermoluminescent dosimeters. The risk associated with the neutron and gamma radiation dose equivalents received by both the irradiated phantom and medical researchers were evaluated in detail. The radiation safety of the in-vivo medical diagnosis using the mobile nuclear reactor, under the context of radiation protection guidelines, is discussed.

  11. New capabilities and applications for electrophoretically deposited coatings

    SciTech Connect

    Sharp, D.J.

    1991-01-01

    Our primary purpose in this test is to provide a brief general description of a few applications of various electrophoretic systems which have been investigated and have found use in various coating applications at Sandia National Laboratories. Both organic and inorganic suspensions in aqueous and non-aqueous media have been considered in these studies. Applications include high voltage insulating dielectrics, thermally conductive/electrically insulating films, adherent lubricating films, uniform photoresist films, glass coatings, and fissile uranium oxide/carbon composite films for studies of nuclear powered lasers. More recently, we have become interested in the beneficial environmental aspects of being able to provide protective polymer coatings which reduce or minimize the use of organic solvents required by traditional spray coat processes. Important practical factors which relate to film uniformity, adhesion, and composition are related to unique coating or plating capabilities and applications. 6 refs., 2 figs., 1 tab.

  12. Electrophoretic Deposition Applied to Thick Metal-Ceramic Coatings

    SciTech Connect

    Windes, William Enoch; Zimmerman, Jeramy; Reimanis, Ivar E.

    2002-08-01

    Electrophoretic deposition was used to fabricate thick (4 mm) metal–ceramic deposits from a non-aqueous slurry of nickel and alumina particles. A high solid volume in the slurry was identified as the primary parameter for depositing thick cermet coatings rather than the applied electric potential or ionic additive concentration. Ionic additives (MgCl2, AlCl3, etc.) were found to adequately suspend the alumina particles and provide rapid deposition rates. The nickel particles proved to be more difficult to suspend in solution, thereby sacrificing control of the deposition composition. The use of small (3.0 µm) particles and continuously pumping the slurry alleviated the suspension problems but small electric potentials (100 V/cm) were required to avoid the formation of rough, columnar deposits on the depositing electrode.

  13. Electrophoretic deposition of nickel zinc ferrite nanoparticles into microstructured patterns

    NASA Astrophysics Data System (ADS)

    Kelly, Stefan J.; Wen, Xiao; Arnold, David P.; Andrew, Jennifer S.

    2016-05-01

    Using DC electric fields, nickel-zinc ferrite (Ni0.5Zn0.5Fe2O4) nanoparticles (Dh =16.6 ± 3.6 nm) are electrophoretically deposited onto silicon substrates to form dense structures defined by photoresist molds. Parameters such as electric field, bath composition, and deposition time are tuned to produce films ranging in thickness from 177 to 805 nm. The deposited films exhibit soft magnetic properties with a saturation magnetization of 60 emu/g and a coercivity of 2.6 kA/m (33 Oe). Additionally, the influence of the photoresist mold on the deposit profile is studied, and patterned films with different shapes (lines, squares, circles, etc.) are demonstrated with feature sizes down to 5 μm.

  14. Zirconia/alumina functionally gradiented composites by electrophoretic deposition techniques

    SciTech Connect

    Sarkar, P.; Huang, Xuening; Nicholson, P.S. . Dept. of Materials Science and Engineering)

    1993-04-01

    Continuous variation of composition, and thus of physical property, is characteristic of a functionally gradiented material (FGM). Such composite find applications in extreme thermal shielding, the joining of ceramics to metals, optical/electronic functions, and biomaterial implant development. FGMs have been synthesized by chemical vapor deposition (CVD), plasma spraying, self-propagating high-temperature synthesis, and green forming followed by sintering. An electrophoretic deposition and sintering route was used to prepare YSZ/Al[sub 2]O[sub 3] composites with a compositional gradient. The YSZ content was continuously decreased from the YSZ-rich surface to the Al[sub 2]O[sub 3]-rich surface. Microstructural and Vickers hardness (16--24 GPa) evidence tracked the compositional development, and the indentation fracture toughness was found to vary across the section (10--3 MPa[center dot]m[sup 1/2]).

  15. Method for in-situ calibration of electrophoretic analysis systems

    DOEpatents

    Liu, Changsheng; Zhao, Hequan

    2005-05-08

    An electrophoretic system having a plurality of separation lanes is provided with an automatic calibration feature in which each lane is separately calibrated. For each lane, the calibration coefficients map a spectrum of received channel intensities onto values reflective of the relative likelihood of each of a plurality of dyes being present. Individual peaks, reflective of the influence of a single dye, are isolated from among the various sets of detected light intensity spectra, and these can be used to both detect the number of dye components present, and also to establish exemplary vectors for the calibration coefficients which may then be clustered and further processed to arrive at a calibration matrix for the system. The system of the present invention thus permits one to use different dye sets to tag DNA nucleotides in samples which migrate in separate lanes, and also allows for in-situ calibration with new, previously unused dye sets.

  16. Water buffalo (Bubalus bubalis) hemoglobins: an electrophoretic and chromatographic study.

    PubMed

    Di Luccia, A; Iannibelli, L; Ferranti, P; Iorio, M; Annunziata, M; Ferrara, L

    1989-01-01

    1. Hemoglobins from three phenotypes of Italian water buffalo (Bubalus bubalis), named AA, AB and BB, were selected by starch gel electrophoresis at alkaline pH and analyzed using polyacrylamide gel isoelectric focusing and subsequent analysis of titration curves to reveal differences between two types of hemoglobin identified as Hb fast and Hb slow. 2. Globins from Hb fast and Hb slow were purified by fast protein liquid chromatography (FPLC). Electrophoretic differences were found in the respective alpha-chains using polyacrylamide gel disc-electrophoresis at acid pH, polyacrylamide gel isoelectric focusing and by subsequently analyzing titration curves. 3. The results suggest that the alpha chains of Hb fast and Hb slow, called I alpha and II alpha, respectively, differ in at least two aminoacid residues. Subsequently, these amino acids were identified as lysine and cysteine.

  17. Electrophoretic deposition of ultrasonicated and functionalized nanomaterials for multifunctional composites

    NASA Astrophysics Data System (ADS)

    An, Qi

    Recent advances in the synthesis and characterization of nanostructured composite materials have enabled a broad range of opportunities for engineering the properties of polymer-matrix materials. Carbon nanotubes (CNTs) are known to have exceptional mechanical, electrical and thermal properties. Because of their small size, CNTs can occupy regions between traditional micro-scale reinforcements and create a hierarchical micro/nano structure spanning several orders of magnitude. Since CNTs possess critical reinforcement dimensions below 100 nm, new opportunities exist for tailoring the fiber/matrix interphase regions and ultimately the mechanical and electrical performance of advanced fiber-composites with minimal impact on the fiber-dominated properties. This growing interest in nanoscale hybridization with conventional fiber reinforcement has highlighted the need to develop new processing techniques for successful CNT integration. In this work, a novel and industrially scalable approach for producing multi-scale hybrid carbon nanotube/fiber composites using an electrophoretic deposition (EPD) technique has been studied as an alternative to in situ chemical vapor deposition growth (CVD). EPD is a widely used industrial coating process employed in areas ranging from automotive to electronics production. The method has a number of benefits which include low energy use and the ability to homogenously coat complex shapes with well adhered films of controlled thickness and density. A stable aqueous dispersion of multi-walled carbon nanotubes (MWCNTs) was produced using a novel ozonolysis and ultrasonication (USO) technique that results in dispersion and functionalization in a single step. Networks of CNTs span between adjacent fibers and the resulting composites exhibit significant increases in electrical conductivity and considerable improvements in the interlaminar shear strength and fracture toughness. In order to better understand the underlying mechanisms behind the

  18. Characterization of Yersinia enterocolitica, Y. intermedia, Y. aldovae, Y. frederiksenii, Y. kristensenii and Y. pseudotuberculosis by electrophoretic polymorphism of acid phosphatase, esterases, and glutamate and malate dehydrogenases.

    PubMed

    Goullet, P; Picard, B

    1988-02-01

    Acid phosphatase, esterases, and glutamate and malate dehydrogenases of 192 strains of Yersinia enterocolitica, Y. intermedia, Y. aldovae, Y. frederiksenii, Y. kristensenii and Y. pseudotuberculosis were analysed by horizontal polyacrylamide agarose gel electrophoresis and by isoelectrofocusing in thin-layer polyacrylamide gels. The six species were clearly separated from each other by their distinct enzyme electrophoretic polymorphism. For Y. enterocolitica, the strains of biotype 5 were differentiated from the other biotypes by the mobility of glutamate dehydrogenase. For Y. frederiksenii, six zymotypes were delineated by pI and by the mobility of the enzymes. Variation in number or mobility of esterases within each species could represent a marker for epidemiological and ecological analyses. A linear relationship was obtained between the mean genetic diversity coefficient of enzymes and the mean percentage DNA-DNA relatedness of Y. intermedia, Y. aldovae, Y. enterocolitica and Y. frederiksenii.

  19. Weather Effects on the Patterns of People's Everyday Activities: A Study Using GPS Traces of Mobile Phone Users

    PubMed Central

    Leong, Tuck W.; Sekimoto, Yoshihide; Shibasaki, Ryosuke

    2013-01-01

    This study explores the effects that the weather has on people's everyday activity patterns. Temperature, rainfall, and wind speed were used as weather parameters. People's daily activity patterns were inferred, such as place visited, the time this took place, the duration of the visit, based on the GPS location traces of their mobile phones overlaid upon Yellow Pages information. Our analysis of 31,855 mobile phone users allowed us to infer that people were more likely to stay longer at eateries or food outlets, and (to a lesser degree) at retail or shopping areas when the weather is very cold or when conditions are calm (non-windy). When compared to people's regular activity patterns, certain weather conditions affected people's movements and activities noticeably at different times of the day. On cold days, people's activities were found to be more diverse especially after 10AM, showing greatest variations between 2PM and 6PM. A similar trend is observed between 10AM and midnight on rainy days, with people's activities found to be most diverse on days with heaviest rainfalls or on days when the wind speed was stronger than 4 km/h, especially between 10AM–1AM. Finally, we observed that different geographical areas of a large metropolis were impacted differently by the weather. Using data of urban infrastructure to characterize areas, we found strong correlations between weather conditions upon people's accessibility to trains. This study sheds new light on the influence of weather conditions on human behavior, in particular the choice of daily activities and how mobile phone data can be used to investigate the influence of environmental factors on urban dynamics. PMID:24367481

  20. Weather effects on the patterns of people's everyday activities: a study using GPS traces of mobile phone users.

    PubMed

    Horanont, Teerayut; Phithakkitnukoon, Santi; Leong, Tuck W; Sekimoto, Yoshihide; Shibasaki, Ryosuke

    2013-01-01

    This study explores the effects that the weather has on people's everyday activity patterns. Temperature, rainfall, and wind speed were used as weather parameters. People's daily activity patterns were inferred, such as place visited, the time this took place, the duration of the visit, based on the GPS location traces of their mobile phones overlaid upon Yellow Pages information. Our analysis of 31,855 mobile phone users allowed us to infer that people were more likely to stay longer at eateries or food outlets, and (to a lesser degree) at retail or shopping areas when the weather is very cold or when conditions are calm (non-windy). When compared to people's regular activity patterns, certain weather conditions affected people's movements and activities noticeably at different times of the day. On cold days, people's activities were found to be more diverse especially after 10AM, showing greatest variations between 2PM and 6PM. A similar trend is observed between 10AM and midnight on rainy days, with people's activities found to be most diverse on days with heaviest rainfalls or on days when the wind speed was stronger than 4 km/h, especially between 10AM-1AM. Finally, we observed that different geographical areas of a large metropolis were impacted differently by the weather. Using data of urban infrastructure to characterize areas, we found strong correlations between weather conditions upon people's accessibility to trains. This study sheds new light on the influence of weather conditions on human behavior, in particular the choice of daily activities and how mobile phone data can be used to investigate the influence of environmental factors on urban dynamics.

  1. The Lifestyle Interventions and Independence for Elders (LIFE) study, randomized trial of physical activity: Effect on the prevention of major mobility disability

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In older adults reduced mobility is common and is an independent risk factor for morbidity, hospitalization, disability, and mortality. Limited evidence suggests that physical activity may help prevent mobility disability; however, there are no definitive clinical trials examining if physical activi...

  2. Modeling the influence of temperature, water activity and water mobility on the persistence of Salmonella in low-moisture foods.

    PubMed

    Farakos, S M Santillana; Frank, J F; Schaffner, D W

    2013-09-01

    Salmonella can survive in low-moisture foods for long periods of time. Reduced microbial inactivation during heating is believed to be due to the interaction of cells and water, and is thought to be related to water activity (a(w)). Little is known about the role of water mobility in influencing the survival of Salmonella in low-moisture foods. The aim of this study was to determine how the physical state of water in low-moisture foods influences the survival of Salmonella and to use this information to develop mathematical models that predict the behavior of Salmonella in these foods. Whey protein powder of differing water mobilities was produced by pH adjustment and heat denaturation, and then equilibrated to aw levels between 0.19±0.03 and 0.54±0.02. Water mobility was determined by wide-line proton-NMR. Powders were inoculated with a four-strain cocktail of Salmonella, vacuum-sealed and stored at 21, 36, 50, 60, 70 and 80°C. Survival data was fitted to the log-linear, the Geeraerd-tail, the Weibull, the biphasic-linear and the Baranyi models. The model with the best ability to describe the data over all temperatures, water activities and water mobilities (f(test)mobility on the survival of Salmonella was evaluated using multiple linear regression. Secondary models were developed and then validated in dry non-fat dairy and grain, and low-fat peanut and cocoa products within the range of the modeled data. Water activity significantly influenced the survival of Salmonella at all temperatures, survival increasing with decreasing a(w). Water mobility did not significantly influence survival independent of a(w). Secondary models were useful in predicting the survival of Salmonella in various low-moisture foods providing a correlation of R=0.94 and an acceptable prediction performance of 81

  3. Modeling the influence of temperature, water activity and water mobility on the persistence of Salmonella in low-moisture foods.

    PubMed

    Farakos, S M Santillana; Frank, J F; Schaffner, D W

    2013-09-01

    Salmonella can survive in low-moisture foods for long periods of time. Reduced microbial inactivation during heating is believed to be due to the interaction of cells and water, and is thought to be related to water activity (a(w)). Little is known about the role of water mobility in influencing the survival of Salmonella in low-moisture foods. The aim of this study was to determine how the physical state of water in low-moisture foods influences the survival of Salmonella and to use this information to develop mathematical models that predict the behavior of Salmonella in these foods. Whey protein powder of differing water mobilities was produced by pH adjustment and heat denaturation, and then equilibrated to aw levels between 0.19±0.03 and 0.54±0.02. Water mobility was determined by wide-line proton-NMR. Powders were inoculated with a four-strain cocktail of Salmonella, vacuum-sealed and stored at 21, 36, 50, 60, 70 and 80°C. Survival data was fitted to the log-linear, the Geeraerd-tail, the Weibull, the biphasic-linear and the Baranyi models. The model with the best ability to describe the data over all temperatures, water activities and water mobilities (f(test)mobility on the survival of Salmonella was evaluated using multiple linear regression. Secondary models were developed and then validated in dry non-fat dairy and grain, and low-fat peanut and cocoa products within the range of the modeled data. Water activity significantly influenced the survival of Salmonella at all temperatures, survival increasing with decreasing a(w). Water mobility did not significantly influence survival independent of a(w). Secondary models were useful in predicting the survival of Salmonella in various low-moisture foods providing a correlation of R=0.94 and an acceptable prediction performance of 81

  4. Validation and User Evaluation of a Sensor-Based Method for Detecting Mobility-Related Activities in Older Adults

    PubMed Central

    Geraedts, Hilde A. E.; Zijlstra, Wiebren; Van Keeken, Helco G.; Zhang, Wei; Stevens, Martin

    2015-01-01

    Regular physical activity is essential for older adults to stay healthy and independent. However, daily physical activity is generally low among older adults and mainly consists of activities such as standing and shuffling around indoors. Accurate measurement of this low-energy expenditure daily physical activity is crucial for stimulation of activity. The objective of this study was to assess the validity of a necklace-worn sensor-based method for detecting time-on-legs and daily life mobility related postures in older adults. In addition user opinion about the practical use of the sensor was evaluated. Twenty frail and non-frail older adults performed a standardized and free movement protocol in their own home. Results of the sensor-based method were compared to video observation. Sensitivity, specificity and overall agreement of sensor outcomes compared to video observation were calculated. Mobility was assessed based on time-on-legs. Further assessment included the categories standing, sitting, walking and lying. Time-on-legs based sensitivity, specificity and percentage agreement were good to excellent and comparable to laboratory outcomes in other studies. Category-based sensitivity, specificity and overall agreement were moderate to excellent. The necklace-worn sensor is considered an acceptable valid instrument for assessing home-based physical activity based upon time-on-legs in frail and non-frail older adults, but category-based assessment of gait and postures could be further developed. PMID:26361009

  5. Synthesis, characterization and catalytic activity of indium substituted nanocrystalline Mobil Five (MFI) zeolite

    SciTech Connect

    Shah, Kishor Kr.; Nandi, Mithun; Talukdar, Anup K.

    2015-06-15

    Highlights: • In situ modification of the MFI zeolite by incorporation of indium. • The samples were characterized by XRD, FTIR, TGA, UV–vis (DRS), SAA, EDX and SEM. • The incorporation of indium was confirmed by XRD, FT-IR, UV–vis (DRS), EDX and TGA. • Hydroxylation of phenol reaction was studied on the synthesized catalysts. - Abstract: A series of indium doped Mobil Five (MFI) zeolite were synthesized hydrothermally with silicon to aluminium and indium molar ratio of 100 and with aluminium to indium molar ratios of 1:1, 2:1 and 3:1. The MFI zeolite phase was identified by XRD and FT-IR analysis. In XRD analysis the prominent peaks were observed at 2θ values of around 6.5° and 23° with a few additional shoulder peaks in case of all the indium incorporated samples suggesting formation of pure phase of the MFI zeolite. All the samples under the present investigation were found to exhibit high crystallinity (∼92%). The crystallite sizes of the samples were found to vary from about 49 to 55 nm. IR results confirmed the formation of MFI zeolite in all cases showing distinct absorbance bands near 1080, 790, 540, 450 and 990 cm{sup −1}. TG analysis of In-MFI zeolites showed mass losses in three different steps which are attributed to the loss due to adsorbed water molecules and the two types TPA{sup +} cations. Further, the UV–vis (DRS) studies reflected the position of the indium metal in the zeolite framework. Surface area analysis of the synthesized samples was carried out to characterize the synthesized samples The analysis showed that the specific surface area ranged from ∼357 to ∼361 m{sup 2} g{sup −1} and the pore volume of the synthesized samples ranged from 0.177 to 0.182 cm{sup 3} g{sup −1}. The scanning electron microscopy studies showed the structure of the samples to be rectangular and twinned rectangular shaped. The EDX analysis was carried out for confirmation of Si, Al and In in zeolite frame work. The catalytic activities of

  6. An Interactive Concept Map Approach to Supporting Mobile Learning Activities for Natural Science Courses

    ERIC Educational Resources Information Center

    Hwang, Gwo-Jen; Wu, Po-Han; Ke, Hui-Ru

    2011-01-01

    Mobile and wireless communication technologies not only enable anytime and anywhere learning, but also provide the opportunity to develop learning environments that combine real-world and digital-world resources. Nevertheless, researchers have indicated that, without effective tools for helping students organize their observations in the field,…

  7. A Framework for Gamified Activities Based on Mobile Games Played by Portuguese University Students

    ERIC Educational Resources Information Center

    Carvalho, Ana Amélia; Araújo, Inês; Zagalo, Nelson

    2014-01-01

    This paper starts by reporting the findings of a survey of Portuguese university students concerning their game habits and preferences. An online questionnaire was developed and 1101 answers were collected, 626 were mobile game players. The results from the survey indicate that the games most played by university students are essentially casual…

  8. Biochemical Analysis of Autophagy in Algae and Plants by Monitoring the Electrophoretic Mobility of ATG8.

    PubMed

    Pérez-Pérez, María Esther; Andrés-Garrido, Ascensión; Crespo, José L

    2016-01-01

    Identification of specific autophagy markers has been fundamental to investigate autophagy as catabolic process. Among them, the ATG8 protein turned out to be one of the most widely used and specific molecular markers of autophagy both in higher and lower eukaryotes. Here, we describe how ATG8 can be used to monitor autophagy in Chlamydomonas and Arabidopsis by western blot analysis.

  9. Overcharging in biological systems: reversal of electrophoretic mobility of aqueous polyaspartate by multivalent cations.

    PubMed

    Kubíčková, Anna; Křížek, Tomáš; Coufal, Pavel; Vazdar, Mario; Wernersson, Erik; Heyda, Jan; Jungwirth, Pavel

    2012-05-01

    Charge reversal as an extreme case of charge compensation is directly observed by capillary electrophoresis for a negatively charged peptide in aqueous solutions of trivalent cations. Atomistic and coarse-grained simulations provide molecular interpretation of this effect showing that it is largely of electrostatic origin with a minor contribution of chemical specificity of the salt ions.

  10. Characterization of U(VI)-carbonato ternary complexes on hematite: EXAFS and electrophoretic mobility measurements

    USGS Publications Warehouse

    Bargar, John R.; Reitmeyer, Rebecca; Lenhart, John J.; Davis, James A.

    2000-01-01

    We have measured U(VI) adsorption on hematite using EXAFS spectroscopy and electrophoresis under conditions relevant to surface waters and aquifers (0.01 to 10 μM dissolved uranium concentrations, in equilibrium with air, pH 4.5 to 8.5). Both techniques suggest the existence of anionic U(VI)-carbonato ternary complexes. Fits to EXAFS spectra indicate that U(VI) is simultaneously coordinated to surface FeO6 octahedra and carbonate (or bicarbonate) ligands in bidentate fashions, leading to the conclusion that the ternary complexes have an inner-sphere metal bridging (hematite-U(VI)-carbonato) structure. Greater than or equal to 50% of adsorbed U(VI) was comprised of monomeric hematite-U(VI)-carbonato ternary complexes, even at pH 4.5. Multimeric U(VI) species were observed at pH ≥ 6.5 and aqueous U(VI) concentrations approximately an order of magnitude more dilute than the solubility of crystalline β-UO2(OH)2. Based on structural constraints, these complexes were interpreted as dimeric hematite-U(VI)-carbonato ternary complexes. These results suggest that Fe-oxide-U(VI)-carbonato complexes are likely to be important transport-limiting species in oxic aquifers throughout a wide range of pH values.

  11. Biochemical Analysis of Autophagy in Algae and Plants by Monitoring the Electrophoretic Mobility of ATG8.

    PubMed

    Pérez-Pérez, María Esther; Andrés-Garrido, Ascensión; Crespo, José L

    2016-01-01

    Identification of specific autophagy markers has been fundamental to investigate autophagy as catabolic process. Among them, the ATG8 protein turned out to be one of the most widely used and specific molecular markers of autophagy both in higher and lower eukaryotes. Here, we describe how ATG8 can be used to monitor autophagy in Chlamydomonas and Arabidopsis by western blot analysis. PMID:27424752

  12. Water activity and mobility in solutions of glycerol and small molecular weight sugars: Implication for cryo- and lyopreservation

    NASA Astrophysics Data System (ADS)

    He, Xiaoming; Fowler, Alex; Toner, Mehmet

    2006-10-01

    In this study, the free volume models, originally developed for large molecular weight polymer-solvent systems, were used to study the water activity and mobility in solutions of four small molecular weight cryo-/lyoprotectants, viz., glycerol, a monosaccharide (fructose), and two disaccharides (sucrose and trehalose). The free volume model parameters were determined by fitting the models to available experimental data using a nonlinear optimization procedure. It was found that free volume models could accurately predict the available experimental data, which suggests that the free volume models might be generally applicable to aqueous solutions of small molecular weight cryo-/lyoprotectants. Furthermore, several models for estimating the mutual diffusion coefficient were tested using available experimental data for aqueous solutions of glycerol and a better method to estimate the mutual diffusion coefficient was proposed. Free volume models were used to predict and analyze the water activity and mobility in solutions of four cryo-/lyoprotectants under conditions frequently encountered in cryo-/lyopreservation applications. It was found that the water mobility in the glassy state of the above four solutions is essentially negligible in the case of cryopreservation with storage temperature lower than -110°C. However, the water mobility in a glass at higher temperature (>-80°C) may be significant. As a result, a subcooling of up to 50°C may be necessary for the long-term cryo-/lyopreservation of biomaterials depending on the water content and the type of cryo-/lyoprotectants. It was further shown that trehalose might be the best of the four protectants studied for lyopreservation (water mass fraction ⩽0.1) when the storage temperature is above the room temperature. The results from this study might be useful for the development of more effective protocols for both cryopreservation and lyopreservation of living cells and other biomaterials.

  13. On the use of the activation energy concept to investigate analyte and network deformations in entangled polymer solution capillary electrophoresis of synthetic polyelectrolytes.

    PubMed

    Cottet, H; Gareil, P

    2001-01-01

    The activation energy associated with the electrophoretic migration of an analyte under given electrolyte conditions can be accessed through the determination of the analyte electrophoretic mobility at various temperatures. In the case of the electrophoretic separation of polyelectrolytes in the presence of an entangled polymer network, activation energy can be regarded as the energy needed by the analyte to overcome the obstacles created by the separating network. Any deformation undergone by the analyte or the network is expected to induce a decrease in the activation energy. In this work, the electrophoretic mobilities of poly(styrenesulfonates) (PSSs) of various molecular weights (Mr 16 x 10(3) to 990 x 10(3)) were determined in entangled polyethylene oxide (PEO) solutions as a function of temperature (in the 17-60 degrees C range) and the PSS activation energies were calculated. The influences of the PSS molecular weight, blob sizes zetab of the separating network (related to the PEO concentration), ionic strength of the electrolyte and electric field strength (75-600 V/cm) were investigated. The results were interpreted in terms of analyte and network deformations and were confronted with those previously obtained for DNA migration in polymer solutions and chemical gels. For a radius of gyration Rgactivation energy increases with the PSS molecular mass, while the reverse is true for Rg>zetab, suggesting PSS and network deformations in the latter case. Increasing ionic strength resulted in an increase in the PSS activation energy, because of the decrease of their radii of gyration, which makes them less deformable. Finally, the activation energies of all the PSSs are a decreasing function of field strength and at high field strength tend to reach a constant value close to that for a small molecule.

  14. Multilocus Electrophoretic Assessment of the Genetic Structure and Diversity of Yersinia ruckeri

    PubMed Central

    Schill, William B.; Phelps, Stevan R.; Pyle, Stephen W.

    1984-01-01

    Multilocus isoenzyme electrophoresis was used to screen 47 field isolates of Yersinia ruckeri for electrophoretic variation at 15 enzyme loci. Only four electrophoretic types were observed, thus indicating that the genetic structure of Y. ruckeri is clonal. Forty-two isolates were of one electrophoretic type, a reflection of the low amount of genetic diversity extant in this species. Although sorbitol fermentation has been considered to be indicative of a second biotype, no significant gene frequency differences were found between the group of 20 isolates that readily used sorbitol as the sole carbon source and the group of 27 that did not. Images PMID:16346669

  15. On the asynchronously continuous control of mobile robot movement by motor cortical spiking activity.

    PubMed

    Xu, Zhiming; So, Rosa Q; Toe, Kyaw Kyar; Ang, Kai Keng; Guan, Cuntai

    2014-01-01

    This paper presents an asynchronously intracortical brain-computer interface (BCI) which allows the subject to continuously drive a mobile robot. This system has a great implication for disabled patients to move around. By carefully designing a multiclass support vector machine (SVM), the subject's self-paced instantaneous movement intents are continuously decoded to control the mobile robot. In particular, we studied the stability of the neural representation of the movement directions. Experimental results on the nonhuman primate showed that the overt movement directions were stably represented in ensemble of recorded units, and our SVM classifier could successfully decode such movements continuously along the desired movement path. However, the neural representation of the stop state for the self-paced control was not stably represented and could drift. PMID:25570634

  16. On the asynchronously continuous control of mobile robot movement by motor cortical spiking activity.

    PubMed

    Xu, Zhiming; So, Rosa Q; Toe, Kyaw Kyar; Ang, Kai Keng; Guan, Cuntai

    2014-01-01

    This paper presents an asynchronously intracortical brain-computer interface (BCI) which allows the subject to continuously drive a mobile robot. This system has a great implication for disabled patients to move around. By carefully designing a multiclass support vector machine (SVM), the subject's self-paced instantaneous movement intents are continuously decoded to control the mobile robot. In particular, we studied the stability of the neural representation of the movement directions. Experimental results on the nonhuman primate showed that the overt movement directions were stably represented in ensemble of recorded units, and our SVM classifier could successfully decode such movements continuously along the desired movement path. However, the neural representation of the stop state for the self-paced control was not stably represented and could drift.

  17. Harnessing Different Motivational Frames via Mobile Phones to Promote Daily Physical Activity and Reduce Sedentary Behavior in Aging Adults

    PubMed Central

    King, Abby C.; Hekler, Eric B.; Grieco, Lauren A.; Winter, Sandra J.; Sheats, Jylana L.; Buman, Matthew P.; Banerjee, Banny; Robinson, Thomas N.; Cirimele, Jesse

    2013-01-01

    Mobile devices are a promising channel for delivering just-in-time guidance and support for improving key daily health behaviors. Despite an explosion of mobile phone applications aimed at physical activity and other health behaviors, few have been based on theoretically derived constructs and empirical evidence. Eighty adults ages 45 years and older who were insufficiently physically active, engaged in prolonged daily sitting, and were new to smartphone technology, participated in iterative design development and feasibility testing of three daily activity smartphone applications based on motivational frames drawn from behavioral science theory and evidence. An “analytically” framed custom application focused on personalized goal setting, self-monitoring, and active problem solving around barriers to behavior change. A “socially” framed custom application focused on social comparisons, norms, and support. An “affectively” framed custom application focused on operant conditioning principles of reinforcement scheduling and emotional transference to an avatar, whose movements and behaviors reflected the physical activity and sedentary levels of the user. To explore the applications' initial efficacy in changing regular physical activity and leisure-time sitting, behavioral changes were assessed across eight weeks in 68 participants using the CHAMPS physical activity questionnaire and the Australian sedentary behavior questionnaire. User acceptability of and satisfaction with the applications was explored via a post-intervention user survey. The results indicated that the three applications were sufficiently robust to significantly improve regular moderate-to-vigorous intensity physical activity and decrease leisure-time sitting during the 8-week behavioral adoption period. Acceptability of the applications was confirmed in the post-intervention surveys for this sample of midlife and older adults new to smartphone technology. Preliminary data exploring

  18. Harnessing different motivational frames via mobile phones to promote daily physical activity and reduce sedentary behavior in aging adults.

    PubMed

    King, Abby C; Hekler, Eric B; Grieco, Lauren A; Winter, Sandra J; Sheats, Jylana L; Buman, Matthew P; Banerjee, Banny; Robinson, Thomas N; Cirimele, Jesse

    2013-01-01

    Mobile devices are a promising channel for delivering just-in-time guidance and support for improving key daily health behaviors. Despite an explosion of mobile phone applications aimed at physical activity and other health behaviors, few have been based on theoretically derived constructs and empirical evidence. Eighty adults ages 45 years and older who were insufficiently physically active, engaged in prolonged daily sitting, and were new to smartphone technology, participated in iterative design development and feasibility testing of three daily activity smartphone applications based on motivational frames drawn from behavioral science theory and evidence. An "analytically" framed custom application focused on personalized goal setting, self-monitoring, and active problem solving around barriers to behavior change. A "socially" framed custom application focused on social comparisons, norms, and support. An "affectively" framed custom application focused on operant conditioning principles of reinforcement scheduling and emotional transference to an avatar, whose movements and behaviors reflected the physical activity and sedentary levels of the user. To explore the applications' initial efficacy in changing regular physical activity and leisure-time sitting, behavioral changes were assessed across eight weeks in 68 participants using the CHAMPS physical activity questionnaire and the Australian sedentary behavior questionnaire. User acceptability of and satisfaction with the applications was explored via a post-intervention user survey. The results indicated that the three applications were sufficiently robust to significantly improve regular moderate-to-vigorous intensity physical activity and decrease leisure-time sitting during the 8-week behavioral adoption period. Acceptability of the applications was confirmed in the post-intervention surveys for this sample of midlife and older adults new to smartphone technology. Preliminary data exploring sustained use

  19. Harnessing different motivational frames via mobile phones to promote daily physical activity and reduce sedentary behavior in aging adults.

    PubMed

    King, Abby C; Hekler, Eric B; Grieco, Lauren A; Winter, Sandra J; Sheats, Jylana L; Buman, Matthew P; Banerjee, Banny; Robinson, Thomas N; Cirimele, Jesse

    2013-01-01

    Mobile devices are a promising channel for delivering just-in-time guidance and support for improving key daily health behaviors. Despite an explosion of mobile phone applications aimed at physical activity and other health behaviors, few have been based on theoretically derived constructs and empirical evidence. Eighty adults ages 45 years and older who were insufficiently physically active, engaged in prolonged daily sitting, and were new to smartphone technology, participated in iterative design development and feasibility testing of three daily activity smartphone applications based on motivational frames drawn from behavioral science theory and evidence. An "analytically" framed custom application focused on personalized goal setting, self-monitoring, and active problem solving around barriers to behavior change. A "socially" framed custom application focused on social comparisons, norms, and support. An "affectively" framed custom application focused on operant conditioning principles of reinforcement scheduling and emotional transference to an avatar, whose movements and behaviors reflected the physical activity and sedentary levels of the user. To explore the applications' initial efficacy in changing regular physical activity and leisure-time sitting, behavioral changes were assessed across eight weeks in 68 participants using the CHAMPS physical activity questionnaire and the Australian sedentary behavior questionnaire. User acceptability of and satisfaction with the applications was explored via a post-intervention user survey. The results indicated that the three applications were sufficiently robust to significantly improve regular moderate-to-vigorous intensity physical activity and decrease leisure-time sitting during the 8-week behavioral adoption period. Acceptability of the applications was confirmed in the post-intervention surveys for this sample of midlife and older adults new to smartphone technology. Preliminary data exploring sustained use

  20. A mobile laboratory for surface and subsurface imaging in geo-hazard monitoring activity

    NASA Astrophysics Data System (ADS)

    Cornacchia, Carmela; Bavusi, Massimo; Loperte, Antonio; Pergola, Nicola; Pignatti, Stefano; Ponzo, Felice; Lapenna, Vincenzo

    2010-05-01

    high data acquisition repetition rate up to 500.000 pxl/sec with a range resolution of 0.1 mm, vertical and horizontal FoV of 310° and 360° respectively with a resolution of 0.0018°. The system is also equipped with a metric camera allows to georeference the high resolution images acquired. The electromagnetic sensors allow to obtain in near real time high-resolution 2D and 3D subsurface tomographic images. The main components are a fully automatic resistivity meter for DC electrical surveys (resistivity) and Induced Polarization, a Ground Penetrating Radar with antennas covering range for 400 MHz to 1.5 GHz and a gradiometric magnetometric system. All the sensors can be installed on a mobile van and remotely controlled using wi-fi technologies. An all-time network connection capability is guaranteed by a self-configurable satellite link for data communication, which allows to transmit in near-real time experimental data coming from the field surveys and to share other geospatial information. This ICT facility is well suited for emergency response activities during and after catastrophic events. Sensor synergy, multi-temporal and multi-scale resolutions of surface and sub-surface imaging are the key technical features of this instrumental facility. Finally, in this work we shortly present some first preliminary results obtained during the emergence phase of Abruzzo earthquake (Central Italy).

  1. Survival, mobility, and membrane-bound enzyme activities of freshwater planarian, Dugesia japonica, exposed to synthetic and natural surfactants.

    PubMed

    Li, Mei-Hui

    2012-04-01

    Surfactants are a major class of emerging pollutants widely used in large quantities in everyday life and commonly found in surface waters worldwide. Freshwater planarian was selected to examine the effects of different surfactants by measuring mortality, mobility, and membrane-bound enzyme activities. Among the 10 surfactants tested, the acute toxicities of betaine and polyethylene glycol (PEG-200) to planarians were relatively low, with a median lethal concentration (LC50) greater than 10,000 mg/L. The toxicity to planarians of the other eight surfactants based on 48-h LC50 could be arranged in the descending order of cetylpyridinum chloride (CPC) > 4-tert-octylphenol (4-tert-OP) > ammonium lauryl sulfate > benzalkonium chloride > saponin > sodium lauroylsarcosinate > dioctyl sulfosuccinate > dodecyl trimethyl ammonium bromide (DTAB). Both CPC and 4-tert-OP were very toxic to planarians, with 48-h LC50 values <1 mg/L. The median effective concentrations (EC50s) of planarian mobility were in the 0.1 to 50 mg/L range and were in the same range as the 24-h LC50 of planarians exposed to different surfactants, except for DTAB. In addition, significant inhibition of cholinesterase activity activities was found in planarians exposed to 4-tert-OP at 2.5 and 5 mg/L and to saponin at 10 mg/L after 2-h treatments. This result suggests that planarian mobility responses can be used as an alternative indicator for acute toxicity of surfactants after a very short exposure period.

  2. From Data Acquisition to Data Fusion: A Comprehensive Review and a Roadmap for the Identification of Activities of Daily Living Using Mobile Devices

    PubMed Central

    Pires, Ivan Miguel; Garcia, Nuno M.; Pombo, Nuno; Flórez-Revuelta, Francisco

    2016-01-01

    This paper focuses on the research on the state of the art for sensor fusion techniques, applied to the sensors embedded in mobile devices, as a means to help identify the mobile device user’s daily activities. Sensor data fusion techniques are used to consolidate the data collected from several sensors, increasing the reliability of the algorithms for the identification of the different activities. However, mobile devices have several constraints, e.g., low memory, low battery life and low processing power, and some data fusion techniques are not suited to this scenario. The main purpose of this paper is to present an overview of the state of the art to identify examples of sensor data fusion techniques that can be applied to the sensors available in mobile devices aiming to identify activities of daily living (ADLs). PMID:26848664

  3. Phospholipase C-η1 is activated by intracellular Ca(2+) mobilization and enhances GPCRs/PLC/Ca(2+) signaling.

    PubMed

    Kim, Jung Kuk; Choi, Jung Woong; Lim, Seyoung; Kwon, Ohman; Seo, Jeong Kon; Ryu, Sung Ho; Suh, Pann-Ghill

    2011-06-01

    Phospholipase C-η1 (PLC-η1) is the most recently identified PLC isotype and is primarily expressed in nerve tissue. However, its functional role is unclear. In the present study, we report for the first time that PLC-η1 acts as a signal amplifier in G protein-coupled receptor (GPCR)-mediated PLC and Ca(2+) signaling. Short-hairpin RNA (shRNA)-mediated knockdown of endogenous PLC-η1 reduced lysophosphatidic acid (LPA)-, bradykinin (BK)-, and PACAP-induced PLC activity in mouse neuroblastoma Neuro2A (N2A) cells, indicating that PLC-η1 participates in GPCR-mediated PLC activation. Interestingly, ionomycin-induced PLC activity was significantly decreased by PLC-η1, but not PLC-η2, knockdown. In addition, we found that intracellular Ca(2+) source is enough for PLC-η1 activation. Furthermore, the IP(3) receptor inhibitor, 2-APB, inhibited LPA-induced PLC activity in control N2A cells, whereas this effect was not observed in PLC-η1 knockdown N2A cells, suggesting a pivotal role of intracellular Ca(2+) mobilization in PLC-η1 activation. Finally, we found that LPA-induced ERK1/2 phosphorylation and expression of the downstream target gene, krox-24, were significantly decreased by PLC-η1 knockdown, and these knockdown effects were abolished by 2-APB. Taken together, our results strongly suggest that PLC-η1 is activated via intracellular Ca(2+) mobilization from the ER, and therefore amplifies GPCR-mediated signaling.

  4. Lateral Mobility and Nanoscale Spatial Arrangement of Chemokine-activated α4β1 Integrins on T Cells*

    PubMed Central

    Sosa-Costa, Alberto; Isern de Val, Sol; Sevilla-Movilla, Silvia; Teixidó, Joaquin

    2016-01-01

    Chemokine stimulation of integrin α4β1-dependent T lymphocyte adhesion is a key step during lymphocyte trafficking. A central question regarding α4β1 function is how its lateral mobility and organization influence its affinity and avidity following cell stimulation with chemokines and/or ligands. Using single particle tracking and superresolution imaging approaches, we explored the lateral mobility and spatial arrangement of individual α4β1integrins on T cells exposed to different activating stimuli. We show that CXCL12 stimulation leads to rapid and transient α4β1activation, measured by induction of the activation epitope recognized by the HUTS-21 anti-β1antibody and by increased talin-β1 association. CXCL12-dependent α4β1 activation directly correlated with restricted lateral diffusion and integrin immobilization. Moreover, co-stimulation by CXCL12 together with soluble VCAM-1 potentiated integrin immobilization with a 5-fold increase in immobile integrins compared with unstimulated conditions. Our data indicate that docking by talin of the chemokine-activated α4β1 to the actin cytoskeleton favors integrin immobilization, which likely facilitates ligand interaction and increased adhesiveness. Superresolution imaging showed that the nanoscale organization of high-affinity α4β1 remains unaffected following chemokine and/or ligand addition. Instead, newly activated α4β1 integrins organize on the cell membrane as independent units without joining pre-established integrin sites to contribute to cluster formation. Altogether, our results provide a rationale to understand how the spatiotemporal organization of activated α4β1 integrins regulates T lymphocyte adhesion. PMID:27481944

  5. AC electrophoretic deposition of organic-inorganic composite coatings.

    PubMed

    Yoshioka, T; Chávez-Valdez, A; Roether, J A; Schubert, D W; Boccaccini, A R

    2013-02-15

    Alternating current electrophoretic deposition (AC-EPD) of polyacrylic acid (PAA)-titanium oxide (TiO(2)) nanoparticle composites on stainless steel electrodes was investigated in basic aqueous solution. AC square wave with duty cycle of 80% was applied at a frequency of 1 kHz. FTIR-ATR spectra showed that both AC and direct current (DC) EPD successfully deposited PAA-TiO(2) composites. The deposition rate using AC-EPD was lower than that obtained in direct current DC-EPD. However, the microstructure and surface morphology of the deposited composite coatings were different depending on the type of electric field applied. AC-EPD applied for not more than 5 min led to smooth films without bubble formation, while DC-EPD for 1 min or more showed deposits with microstructural defects possibly as result of water electrolysis. AC-EPD was thus for the first time demonstrated to be a suitable technique to deposit organic-inorganic composite coatings from aqueous suspensions, showing that applying a square wave and frequency of 1 kHz leads to uniform PAA-TiO(2) composite coatings on conductive materials. PMID:23218240

  6. Electrophoretic and immunoblot analyses of Rhizopus arrhizus antigens.

    PubMed Central

    Wysong, D R; Waldorf, A R

    1987-01-01

    Four antigen preparations from Rhizopus arrhizus were made and analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and column chromatography. Electrophoretic analyses of these antigens indicated that there are 18 to 28 component bands with a molecular mass range of approximately 10,500 to 83,000 daltons. Seven of these bands appear to be components common to three antigen preparations. Several of the bands identified by SDS-PAGE were composed of glycoproteins or carbohydrates as determined by their affinity for concanavalin A. Western blots, using sera from five patients with mucormycosis, consistently identified five different determinants in the R. arrhizus antigens separated by SDS-PAGE. This suggests that several of the Rhizopus antigens are present during mucormycosis. Four of the antigenic determinants recognized by patient sera reacted with the concanavalin A-peroxidase stain, indicating that they are composed of glycoproteins or carbohydrate. Enzyme-linked immunosorbent assays of sera from five patients with mucormycosis and with rabbit antisera resulted in antibody titers ranging from 1:64 to 1:32,000 for the R. arrhizus antigens. Images PMID:3546367

  7. Electrophoretic and immunoblot analyses of Rhizopus arrhizus antigens.

    PubMed

    Wysong, D R; Waldorf, A R

    1987-02-01

    Four antigen preparations from Rhizopus arrhizus were made and analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and column chromatography. Electrophoretic analyses of these antigens indicated that there are 18 to 28 component bands with a molecular mass range of approximately 10,500 to 83,000 daltons. Seven of these bands appear to be components common to three antigen preparations. Several of the bands identified by SDS-PAGE were composed of glycoproteins or carbohydrates as determined by their affinity for concanavalin A. Western blots, using sera from five patients with mucormycosis, consistently identified five different determinants in the R. arrhizus antigens separated by SDS-PAGE. This suggests that several of the Rhizopus antigens are present during mucormycosis. Four of the antigenic determinants recognized by patient sera reacted with the concanavalin A-peroxidase stain, indicating that they are composed of glycoproteins or carbohydrate. Enzyme-linked immunosorbent assays of sera from five patients with mucormycosis and with rabbit antisera resulted in antibody titers ranging from 1:64 to 1:32,000 for the R. arrhizus antigens.

  8. AC electrophoretic deposition of organic-inorganic composite coatings.

    PubMed

    Yoshioka, T; Chávez-Valdez, A; Roether, J A; Schubert, D W; Boccaccini, A R

    2013-02-15

    Alternating current electrophoretic deposition (AC-EPD) of polyacrylic acid (PAA)-titanium oxide (TiO(2)) nanoparticle composites on stainless steel electrodes was investigated in basic aqueous solution. AC square wave with duty cycle of 80% was applied at a frequency of 1 kHz. FTIR-ATR spectra showed that both AC and direct current (DC) EPD successfully deposited PAA-TiO(2) composites. The deposition rate using AC-EPD was lower than that obtained in direct current DC-EPD. However, the microstructure and surface morphology of the deposited composite coatings were different depending on the type of electric field applied. AC-EPD applied for not more than 5 min led to smooth films without bubble formation, while DC-EPD for 1 min or more showed deposits with microstructural defects possibly as result of water electrolysis. AC-EPD was thus for the first time demonstrated to be a suitable technique to deposit organic-inorganic composite coatings from aqueous suspensions, showing that applying a square wave and frequency of 1 kHz leads to uniform PAA-TiO(2) composite coatings on conductive materials.

  9. Integrated Microfluidic Isolation of Aptamers Using Electrophoretic Oligonucleotide Manipulation

    NASA Astrophysics Data System (ADS)

    Kim, Jinho; Olsen, Timothy R.; Zhu, Jing; Hilton, John P.; Yang, Kyung-Ae; Pei, Renjun; Stojanovic, Milan N.; Lin, Qiao

    2016-05-01

    We present a microfluidic approach to integrated isolation of DNA aptamers via systematic evolution of ligands by exponential enrichment (SELEX). The approach employs a microbead-based protocol for the processes of affinity selection and amplification of target-binding oligonucleotides, and an electrophoretic DNA manipulation scheme for the coupling of these processes, which are required to occur in different buffers. This achieves the full microfluidic integration of SELEX, thereby enabling highly efficient isolation of aptamers in drastically reduced times and with minimized consumption of biological material. The approach as such also offers broad target applicability by allowing selection of aptamers with respect to targets that are either surface-immobilized or solution-borne, potentially allowing aptamers to be developed as readily available affinity reagents for a wide range of targets. We demonstrate the utility of this approach on two different procedures, respectively for isolating aptamers against a surface-immobilized protein (immunoglobulin E) and a solution-phase small molecule (bisboronic acid in the presence of glucose). In both cases aptamer candidates were isolated in three rounds of SELEX within a total process time of approximately 10 hours.

  10. Solubilization and electrophoretic characterization of select edible nut seed proteins.

    PubMed

    Sathe, Shridhar K; Venkatachalam, Mahesh; Sharma, Girdhari M; Kshirsagar, Harshal H; Teuber, Suzanne S; Roux, Kenneth H

    2009-09-01

    The solubility of almond, Brazil nut, cashew nut, hazelnut, macadamia, pecan, pine nut, pistachio, walnut, and peanut proteins in several aqueous solvents was qualitatively and quantitatively assessed. In addition, the effects of extraction time and ionic strength on protein solubility were also investigated. Electrophoresis and protein determination (Lowry, Bradford, and micro-Kjeldahl) methods were used for qualitative and quantitative assessment of proteins, respectively. Depending on the seed, buffer type and ionic strength significantly affected protein solubility. The results suggest that buffered sodium borate (BSB; 0.1 M H(3)BO(3), 0.025 M Na(2)B(4)O(7), 0.075 M NaCl, pH 8.45) optimally solubilizes nut seed proteins. Qualitative differences in seed protein electrophoretic profiles were revealed. For a specific seed type, these differences were dependent on the solvent(s) used to solubilize the seed proteins. SDS-PAGE results suggest the polypeptide molecular mass range for the tree nut seed proteins to be 3-100 kDa. The results of native IEF suggested that the proteins were mainly acidic, with a pI range from >4.5 to <7.0. Western immunoblotting experiments indicated that rabbit polyclonal antibodies recognized substantially the same polypeptides as those recognized by the corresponding pooled patient sera IgE.

  11. Origami paper-based fluidic batteries for portable electrophoretic devices.

    PubMed

    Chen, Sung-Sheng; Hu, Chih-Wei; Yu, I-Fan; Liao, Ying-Chih; Yang, Jing-Tang

    2014-06-21

    A manufacturing approach for paper-based fluidic batteries was developed based on the origami principle (three-dimension paper folding). Microfluidic channels were first created on a filter paper by a wax-printing method. Copper and aluminium sheets were then glued onto the paper as electrodes for the redox reaction. After the addition of copper sulphate and aluminium chloride, commonly available cellophane paper was attached as a membrane to separate the two electrodes. The resulting planar paper sheets were then folded into three-dimensional structures and compiled as a single battery with glue. The two half reactions (Al/Al(3+) and Cu/Cu(2+)) in the folded batteries provided an open-circuit potential from 0.82 V (one cell) to 5.0 V (eight cells in series) depending on the origami design. The prepared battery can provide a stable current of 500 μA and can light a regular LED for more than 65 min. These paper-based fluidic batteries in a set can also be compiled into a portable power bank to provide electric power for many electric or biomedical applications, such as LED lights and electrophoretic devices, as we report here. PMID:24811036

  12. Solution ripening of hydroxyapatite nanoparticles: effects on electrophoretic deposition.

    PubMed

    Wei, M; Ruys, A J; Milthorpe, B K; Sorrell, C C

    1999-04-01

    Electrophoretic deposition is a low-cost, simple, and flexible coating method for producing hydroxyapatite (Hap) coatings on metal implants. However, densification requires heating the coated metal to high temperatures, which, for commercial HAp powders, generally means at least 1200 degrees C. At such temperatures, the metal tends to react with the HAp coating, inducing decomposition, and the strength of titanium and stainless steel implants is severely degraded. With the use of raw uncalcined nanoparticulate Hap, densification can occur at 900 degrees -1050 degrees C; however, such coatings are prone to cracking due to the high drying shrinkage. This problem was solved by precipitating nanoparticulate HAp by the metathesis process [10Ca(NO3)2 + 6NH4H2PO4 + 8NH4OH] and optimizing the approximately 30 nm of nanoprecipitates by an Ostwald ripening approach, that is, by boiling and/or ambient aging in the mother liquor. While the as-precipitated nanoparticles produced severely cracked coatings, 2 h of boiling or 10 days of ambient aging ripened the "gel-like" mass into unagglomerated nanoparticles, which produced crack-free coatings. Since boiling enhanced particle size but ambient aging did not, crack elimination probably was due to the transition from the highly agglomerated gel-like state to the dispersed nanoparticulate state rather than to particle growth. Furthermore, boiling only reduced the amount of cracking whereas aging completely eliminated cracking.

  13. Origami paper-based fluidic batteries for portable electrophoretic devices.

    PubMed

    Chen, Sung-Sheng; Hu, Chih-Wei; Yu, I-Fan; Liao, Ying-Chih; Yang, Jing-Tang

    2014-06-21

    A manufacturing approach for paper-based fluidic batteries was developed based on the origami principle (three-dimension paper folding). Microfluidic channels were first created on a filter paper by a wax-printing method. Copper and aluminium sheets were then glued onto the paper as electrodes for the redox reaction. After the addition of copper sulphate and aluminium chloride, commonly available cellophane paper was attached as a membrane to separate the two electrodes. The resulting planar paper sheets were then folded into three-dimensional structures and compiled as a single battery with glue. The two half reactions (Al/Al(3+) and Cu/Cu(2+)) in the folded batteries provided an open-circuit potential from 0.82 V (one cell) to 5.0 V (eight cells in series) depending on the origami design. The prepared battery can provide a stable current of 500 μA and can light a regular LED for more than 65 min. These paper-based fluidic batteries in a set can also be compiled into a portable power bank to provide electric power for many electric or biomedical applications, such as LED lights and electrophoretic devices, as we report here.

  14. Electrophoretic coating of amphiphilic chitosan colloids on regulating cellular behaviour.

    PubMed

    Wang, Yen-Jen; Lo, Teng-Yuan; Wu, Chieh-Hsi; Liu, Dean-Mo

    2013-09-01

    In this communication, we report a facile nanotopographical control over a stainless steel surface via an electrophoretic deposition of colloidal amphiphilic chitosan for preferential growth, proliferation or migration of vascular smooth muscle cells (VSMCs) and human umbilical vein endothelial cells (HUVECs). Atomic force microscopy revealed that the colloidal surface exhibited a deposition time-dependent nanotopographical evolution, wherein two different nanotopographic textures indexed by 'kurtosis' (Rkur) value were easily designed, which were termed as 'sharp' (i.e. high peak-to-valley texture) surface and 'flat' (i.e. low peak-to-valley texture) surface. Cellular behaviour of VSMCs and HUVECs on both surfaces demonstrated topographically dependent morphogenesis, adherent responses and biochemical properties in comparison with bare stainless steel. The formation of a biofunctionalized surface upon a facile colloidal chitosan deposition envisions the potential application towards numerous biomedical devices, and this is especially promising for cardiovascular stents wherein a new surface with optimized texture can be designed and is expected to create an advantageous environment to stimulate HUVEC growth for improved healing performance. PMID:23804439

  15. Electrophoretic deposition of tannic acid-polypyrrolidone films and composites.

    PubMed

    Luo, Dan; Zhang, Tianshi; Zhitomirsky, Igor

    2016-05-01

    Thin films of polyvinylpyrrolidone (PVP)-tannic acid (TA) complexes were prepared by a conceptually new strategy, based on electrophoretic deposition (EPD). Proof of concept investigations involved the analysis of the deposition yield, FTIR and UV-vis spectroscopy of the deposited material, and electron microscopy studies. The analysis of the deposition mechanism indicated that the limitations of the EPD in the deposition of small phenolic molecules, such as TA, and electrically neutral polymers, similar to PVP, containing hydrogen-accepting carbonyl groups, can be avoided. The remarkable adsorption properties of TA and film forming properties of the PVP-TA complexes allowed for the EPD of materials of different types, such as huntite mineral platelets and hydrotalcite clay particles, TiO2 and MnO2 oxide nanoparticles, multiwalled carbon nanotubes, TiN and Pd nanoparticles. Moreover, PVP-TA complexes were used for the co-deposition of different materials and formation of composite films. In another approach, TA was used as a capping agent for the hydrothermal synthesis of ZnO nanorods, which were then deposited by EPD using PVP-TA complexes. The fundamental adsorption and interaction mechanisms of TA involved chelation of metal atoms on particle surfaces with galloyl groups, π-π interactions and hydrogen bonding. The films prepared by EPD can be used for various applications, utilizing functional properties of TA, PVP, inorganic and organic materials of different types and their composites.

  16. Electrophoretic deposition of tannic acid-polypyrrolidone films and composites.

    PubMed

    Luo, Dan; Zhang, Tianshi; Zhitomirsky, Igor

    2016-05-01

    Thin films of polyvinylpyrrolidone (PVP)-tannic acid (TA) complexes were prepared by a conceptually new strategy, based on electrophoretic deposition (EPD). Proof of concept investigations involved the analysis of the deposition yield, FTIR and UV-vis spectroscopy of the deposited material, and electron microscopy studies. The analysis of the deposition mechanism indicated that the limitations of the EPD in the deposition of small phenolic molecules, such as TA, and electrically neutral polymers, similar to PVP, containing hydrogen-accepting carbonyl groups, can be avoided. The remarkable adsorption properties of TA and film forming properties of the PVP-TA complexes allowed for the EPD of materials of different types, such as huntite mineral platelets and hydrotalcite clay particles, TiO2 and MnO2 oxide nanoparticles, multiwalled carbon nanotubes, TiN and Pd nanoparticles. Moreover, PVP-TA complexes were used for the co-deposition of different materials and formation of composite films. In another approach, TA was used as a capping agent for the hydrothermal synthesis of ZnO nanorods, which were then deposited by EPD using PVP-TA complexes. The fundamental adsorption and interaction mechanisms of TA involved chelation of metal atoms on particle surfaces with galloyl groups, π-π interactions and hydrogen bonding. The films prepared by EPD can be used for various applications, utilizing functional properties of TA, PVP, inorganic and organic materials of different types and their composites. PMID:26878711

  17. Electrophoretic deposition of composite hydroxyapatite-silica-chitosan coatings

    SciTech Connect

    Grandfield, K.; Zhitomirsky, I.

    2008-01-15

    Electrophoretic deposition (EPD) method has been developed for the fabrication of nanocomposite silica-chitosan coatings. Cathodic deposits were obtained on various conductive substrates using suspensions of silica nanoparticles in a mixed ethanol-water solvent, containing dissolved chitosan. Co-deposition of silica and hydroxyapatite (HA) nanoparticles resulted in the fabrication of HA-silica-chitosan coatings. The deposition yield has been studied at a constant voltage mode at various deposition durations. The method enabled the formation of coatings of different thickness in the range of up to 100 {mu}m. Deposit composition, microstructure and porosity can be varied by variation of HA and silica concentration in the suspensions. It was demonstrated that EPD can be used for the fabrication of HA-silica-chitosan coatings of graded composition and laminates. The method enabled the deposition of coatings containing layers of silica-chitosan and HA-chitosan nanocomposites using suspensions with different HA and silica content. Obtained coatings were studied by X-ray diffraction, thermogravimetric and differential thermal analysis, scanning electron microscopy and energy dispersive spectroscopy. The mechanism of deposition is discussed.

  18. Pulsed-field gel electrophoretic analysis of leptospiral DNA.

    PubMed Central

    Taylor, K A; Barbour, A G; Thomas, D D

    1991-01-01

    The genomic structures of spirochete species are not well characterized, and genetic studies on these organisms have been hampered by lack of a genetic exchange mechanism in these bacteria. In view of these observations, pulsed-field gel electrophoresis was used to examine the genomes of Leptospira species. Live cells, prepared in agarose plugs, were lysed in situ, and the DNA was analyzed under different electrophoretic conditions. Pulsed-field gel electrophoresis of DNA digested with infrequently cutting restriction enzymes showed that the genome of Leptospira interrogans serovar canicola is approximately 3.1 Mb, while that of the saprophytic L. biflexa serovar patoc I is 3.5 Mb. DNA forms of approximately 2,000 and 350 kb which were present in samples from L. interrogans serovars were not readily detected in nonpathogenic serovars. Three distinct populations, designated type alpha, beta, and gamma, of L. interrogans DNA molecules were further analyzed with two-dimensional gel electrophoresis. Evidence suggested that two of these DNA forms, type alpha and gamma, were linear structures. Pulsed-field gel electrophoresis has proven to be a valuable tool with which to size bacterial genomes and to take the first steps toward characterization of a form of leptospiral DNA which behaves as a linear molecule and which may be related to the virulence of L. interrogans. Images PMID:1987046

  19. Fabrication of Electrophoretic Display Driven by Membrane Switch Array

    NASA Astrophysics Data System (ADS)

    Kazuo Senda,; Hiroaki Usui,

    2010-04-01

    Electrophoretic devices (EPDs) and organic light-emitting diodes (OLEDs) have potential application in a large-area flexible displays, such as digital signage. For this purpose, a new backplane is capable of driving a large unit is required instead of thin-film transistors. In this paper we describe the fabrication of a membrane switch array suitable for driving large-scale flat-panel displays. An array of membrane switches was prepared using flexible printed circuit (FPC) technology of polyimide films, by combining low-temperature processes of lamination and copper electroplating methods. An array of 256 matrix switches with a pixel size of 7 mm2 was prepared to drive the EPD front panel. The switches were driven at a voltage of about 40 V and a frequency of 10 Hz. The operation characteristics agreed well with the result of the theoretical calculation. The calculation also suggested that driving voltage can be lowered by increasing pixel size. The contact resistance of the membrane switch was as low as 0.2 Ω, which implies the wide applicability of this device for driving a variety of elements.

  20. Integrated Microfluidic Isolation of Aptamers Using Electrophoretic Oligonucleotide Manipulation.

    PubMed

    Kim, Jinho; Olsen, Timothy R; Zhu, Jing; Hilton, John P; Yang, Kyung-Ae; Pei, Renjun; Stojanovic, Milan N; Lin, Qiao

    2016-01-01

    We present a microfluidic approach to integrated isolation of DNA aptamers via systematic evolution of ligands by exponential enrichment (SELEX). The approach employs a microbead-based protocol for the processes of affinity selection and amplification of target-binding oligonucleotides, and an electrophoretic DNA manipulation scheme for the coupling of these processes, which are required to occur in different buffers. This achieves the full microfluidic integration of SELEX, thereby enabling highly efficient isolation of aptamers in drastically reduced times and with minimized consumption of biological material. The approach as such also offers broad target applicability by allowing selection of aptamers with respect to targets that are either surface-immobilized or solution-borne, potentially allowing aptamers to be developed as readily available affinity reagents for a wide range of targets. We demonstrate the utility of this approach on two different procedures, respectively for isolating aptamers against a surface-immobilized protein (immunoglobulin E) and a solution-phase small molecule (bisboronic acid in the presence of glucose). In both cases aptamer candidates were isolated in three rounds of SELEX within a total process time of approximately 10 hours. PMID:27217242

  1. Polyacrylamide medium for the electrophoretic separation of biomolecules

    DOEpatents

    Madabhushi, Ramakrishna S.; Gammon, Stuart A.

    2003-11-11

    A polyacryalmide medium for the electrophoretic separation of biomolecules. The polyacryalmide medium comprises high molecular weight polyacrylamides (PAAm) having a viscosity average molecular weight (M.sub.v) of about 675-725 kDa were synthesized by conventional red-ox polymerization technique. Using this separation medium, capillary electrophoresis of BigDye DNA sequencing standard was performed. A single base resolution of .about.725 bases was achieved in .about.60 minute in a non-covalently coated capillary of 50 .mu.m i.d., 40 cm effective length, and a filed of 160 V/cm at 40.degree. C. The resolution achieved with this formulation to separate DNA under identical conditions is much superior (725 bases vs. 625 bases) and faster (60 min. vs. 75 min.) to the commercially available PAAm, such as supplied by Amersham. The formulation method employed here to synthesize PAAm is straight-forward, simple and does not require cumbersome methods such as emulsion polymerizaiton in order to achieve very high molecular weights. Also, the formulation here does not require separation of PAAm from the reaction mixture prior to reconstituting the polymer to a final concentration. Furthermore, the formulation here is prepared from a single average mol. wt. PAAm as opposed to the mixture of two different average mo. wt. PAAm previously required to achieve high resolution.

  2. Integrated Microfluidic Isolation of Aptamers Using Electrophoretic Oligonucleotide Manipulation

    PubMed Central

    Kim, Jinho; Olsen, Timothy R.; Zhu, Jing; Hilton, John P.; Yang, Kyung-Ae; Pei, Renjun; Stojanovic, Milan N.; Lin, Qiao

    2016-01-01

    We present a microfluidic approach to integrated isolation of DNA aptamers via systematic evolution of ligands by exponential enrichment (SELEX). The approach employs a microbead-based protocol for the processes of affinity selection and amplification of target-binding oligonucleotides, and an electrophoretic DNA manipulation scheme for the coupling of these processes, which are required to occur in different buffers. This achieves the full microfluidic integration of SELEX, thereby enabling highly efficient isolation of aptamers in drastically reduced times and with minimized consumption of biological material. The approach as such also offers broad target applicability by allowing selection of aptamers with respect to targets that are either surface-immobilized or solution-borne, potentially allowing aptamers to be developed as readily available affinity reagents for a wide range of targets. We demonstrate the utility of this approach on two different procedures, respectively for isolating aptamers against a surface-immobilized protein (immunoglobulin E) and a solution-phase small molecule (bisboronic acid in the presence of glucose). In both cases aptamer candidates were isolated in three rounds of SELEX within a total process time of approximately 10 hours. PMID:27217242

  3. Electrophoretic coating of amphiphilic chitosan colloids on regulating cellular behaviour.

    PubMed

    Wang, Yen-Jen; Lo, Teng-Yuan; Wu, Chieh-Hsi; Liu, Dean-Mo

    2013-09-01

    In this communication, we report a facile nanotopographical control over a stainless steel surface via an electrophoretic deposition of colloidal amphiphilic chitosan for preferential growth, proliferation or migration of vascular smooth muscle cells (VSMCs) and human umbilical vein endothelial cells (HUVECs). Atomic force microscopy revealed that the colloidal surface exhibited a deposition time-dependent nanotopographical evolution, wherein two different nanotopographic textures indexed by 'kurtosis' (Rkur) value were easily designed, which were termed as 'sharp' (i.e. high peak-to-valley texture) surface and 'flat' (i.e. low peak-to-valley texture) surface. Cellular behaviour of VSMCs and HUVECs on both surfaces demonstrated topographically dependent morphogenesis, adherent responses and biochemical properties in comparison with bare stainless steel. The formation of a biofunctionalized surface upon a facile colloidal chitosan deposition envisions the potential application towards numerous biomedical devices, and this is especially promising for cardiovascular stents wherein a new surface with optimized texture can be designed and is expected to create an advantageous environment to stimulate HUVEC growth for improved healing performance.

  4. An improved driving waveform reference grayscale of electrophoretic displays

    NASA Astrophysics Data System (ADS)

    Wang, Li; Yi, Zichuan; Peng, Bao; Zhou, Guofu

    2015-10-01

    Driving waveform is an important component for gray scale display on the electrophoretic display (EPD). In the traditional driving waveform, a white reference gray scale is formed before writing a new image. However, the reflectance value can not reach agreement in each gray scale transformation. In this paper, a new driving waveform, which has a short waiting time after the formation of reference gray scale, is proposed to improve the consistency of reference gray scale. Firstly, the property of the particles in the microcapsule is analyzed and the change of the EPD reflectance after the white reference gray scale formation is studied. Secondly, the reflectance change curve is fitted by using polynomial and the duration of the waiting time is determined. Thirdly, a set of the new driving waveform is designed by using the rule of DC balance and some real E-ink commercial EPDs are used to test the performance. Experimental results show that the effect of the new driving waveform has a better performance than traditional waveforms.

  5. Solubilization and electrophoretic characterization of select edible nut seed proteins.

    PubMed

    Sathe, Shridhar K; Venkatachalam, Mahesh; Sharma, Girdhari M; Kshirsagar, Harshal H; Teuber, Suzanne S; Roux, Kenneth H

    2009-09-01

    The solubility of almond, Brazil nut, cashew nut, hazelnut, macadamia, pecan, pine nut, pistachio, walnut, and peanut proteins in several aqueous solvents was qualitatively and quantitatively assessed. In addition, the effects of extraction time and ionic strength on protein solubility were also investigated. Electrophoresis and protein determination (Lowry, Bradford, and micro-Kjeldahl) methods were used for qualitative and quantitative assessment of proteins, respectively. Depending on the seed, buffer type and ionic strength significantly affected protein solubility. The results suggest that buffered sodium borate (BSB; 0.1 M H(3)BO(3), 0.025 M Na(2)B(4)O(7), 0.075 M NaCl, pH 8.45) optimally solubilizes nut seed proteins. Qualitative differences in seed protein electrophoretic profiles were revealed. For a specific seed type, these differences were dependent on the solvent(s) used to solubilize the seed proteins. SDS-PAGE results suggest the polypeptide molecular mass range for the tree nut seed proteins to be 3-100 kDa. The results of native IEF suggested that the proteins were mainly acidic, with a pI range from >4.5 to <7.0. Western immunoblotting experiments indicated that rabbit polyclonal antibodies recognized substantially the same polypeptides as those recognized by the corresponding pooled patient sera IgE. PMID:19655801

  6. Dependence of mobility on density of gap states in organics by GAMEaS-gate modulated activation energy spectroscopy

    NASA Astrophysics Data System (ADS)

    So, Woo-young; Lang, David V.; Butko, Vladimir Y.; Chi, Xiaoliu; Lashley, Jason C.; Ramirez, Arthur P.

    2008-09-01

    We develop a broadly applicable transport-based technique, gate modulated activation energy spectroscopy (GAMEaS), for determining the density of states (DOS) in an energy gap. GAMEaS is applied to field-effect transistors (FETs) made from different single crystal oligomer semiconductors. We find that there are two distinct types of band tails, deep and shallow, depending on the crystallization process. The exponential band tails of the localized DOS are characterized by their slope with the highest mobility FETs having a value of 29 eV-1 close to 1/kBT at 300 K.

  7. Size and DNA distributions of electrophoretically separated cultured human kidney cells

    NASA Technical Reports Server (NTRS)

    Kunze, M. E.; Plank, L. D.; Todd, P. W.

    1985-01-01

    Electrophoretic purification of purifying cultured cells according to function presumes that the size of cycle phase of a cell is not an overriding determinant of its electrophoretic velocity in an electrophoretic separator. The size distributions and DNA distributions of fractions of cells purified by density gradient electrophoresis were determined. No systematic dependence of electrophoretic migration upward in a density gradient column upon either size or DNA content were found. It was found that human leukemia cell populations, which are more uniform function and found in all phases of the cell cycle during exponential growth, separated on a vertical sensity gradient electrophoresis column according to their size, which is shown to be strictly cell cycle dependent.

  8. Improved design of electrophoretic equipment for rapid sickle-cell-anemia screening

    NASA Technical Reports Server (NTRS)

    Reddick, J. M.; Hirsch, I.

    1974-01-01

    Effective mass screening may be accomplished by modifying existing electrophoretic equipment in conjunction with multisample applicator used with cellulose-acetate-matrix test paper. Using this method, approximately 20 to 25 samples can undergo electrophoresis in 5 to 6 minutes.

  9. Affecting proton mobility in activated peptide and whole protein ions via lysine guanidination.

    PubMed

    Pitteri, Sharon J; Reid, Gavin E; McLuckey, Scott A

    2004-01-01

    We have evaluated the effect of lysine guanidination in peptides and proteins on the dissociation of protonated ions in the gas phase. The dissociation of guanidinated model peptide ions compared to their unmodified forms showed behavior consistent with concepts of proton mobility as a major factor in determining favored fragmentation channels. Reduction of proton mobility associated with lysine guanidination was reflected by a relative increase in cleavages occurring C-terminal to aspartic acid residues as well as increases in small molecule losses. To evaluate the effect of guanidination on the dissociation behavior of whole protein ions, bovine ubiquitin was selected as a model. Essentially, all of the amide bond cleavages associated with the +10 charge state of fully guanidinated ubiquitin were observed to occur C-terminal to aspartic acid residues, unlike the dissociation behavior of the +10 ion of the unmodified protein, where competing cleavage N-terminal to proline and nonspecific amide bond cleavages were also observed. The +8 and lower charge states of the guanidinated protein showed prominent losses of small neutral molecules. This overall fragmentation behavior is consistent with current hypotheses regarding whole protein dissociation that consider proton mobility and intramolecular charge solvation as important factors in determining favored dissociation channels, and are also consistent with the fragmentation behaviors observed for the guanidinated model peptide ions. Further evaluation of the utility of condensed phase guanidination of whole proteins is necessary but the results described here confirm that guanidination can be an effective strategy for enhancing C-terminal aspartic acid cleavages. Gas phase dissociation exclusively at aspartic acid residues, especially for whole protein ions, could be useful in identifying and characterizing proteins via tandem mass spectrometry of whole protein ions.

  10. Assessment of heart rate variability based on mobile device for planning physical activity

    NASA Astrophysics Data System (ADS)

    Svirin, I. S.; Epishina, E. V.; Voronin, V. V.; Semenishchev, E. A.; Solodova, E. N.; Nabilskaya, N. V.

    2015-05-01

    In this paper we present a method for the functional analysis of human heart based on electrocardiography (ECG) signals. The approach using the apparatus of analytical and differential geometry and correlation and regression analysis. ECG contains information on the current condition of the cardiovascular system as well as on the pathological changes in the heart. Mathematical processing of the heart rate variability allows to obtain a great set of mathematical and statistical characteristics. These characteristics of the heart rate are used when solving research problems to study physiological changes that determine functional changes of an individual. The proposed method implemented for up-to-date mobile Android and iOS based devices.

  11. The role of cell size in density gradient electrophoretic separation of mouse leukemia cells according to position in the cell cycle

    NASA Technical Reports Server (NTRS)

    Plank, L. D.; Kunze, M. E.; Todd, P. W.

    1985-01-01

    Cultured mouse leukemia cells line L5178Y were subjected to upward electrophoresis in a density gradient and the slower migrating cell populations were enriched in G2 cells. It is indicated that this cell line does not change electrophoretic mobility through the cell cycle. The possibility that increased sedimentation downward on the part of the larger G2 cells caused this separation was explored. Two different cell populations were investigated. The log phase population was found to migrate upward faster than the G2 population, and a similar difference between their velocities and calculated on the basis of a 1 um diameter difference between the two cell populations. The G2 and G1 enriched populations were isolated by Ficoll density gradient sedimentation. The bottom fraction was enriched in G2 cells and the top fraction was enriched with G1 cells, especially when compared with starting materials. The electrophoretic mobilities of these two cell populations did not differ significantly from one another. Cell diameter dependent migration curves were calculated and were found to be different. Families of migration curves that differ when cell size is considered as a parameter are predicted.

  12. Electrophoretic and immunological analyses of almond (Prunusdulcis l.) genotypes and hybrids.

    PubMed

    Sathe, S K; Teuber, S S; Gradziel, T M; Roux, K H

    2001-04-01

    Aqueous extracts from sixty almond samples representing various genotypes and interspecies hybrids of almond, including almond-peach, were analyzed for protein and peptide content using electrophoresis, Western immunoblotting, and enzyme-linked immunosorbent assay (ELISA). Nondenaturing nondissociating polyacrylamide gel electrophoresis (NDND-PAGE) of the aqueous extracts indicated that a single major storage protein (almond major protein -- AMP or amandin) dominated the total soluble protein composition. Denaturing SDS--PAGE analyses of the aqueous extracts revealed that the AMP was mainly composed of two sets of polypeptides with estimated molecular masses in the ranges of 38--41 kDa and 20--22 kDa, regardless of the source; however, distinct variations in the intensity and electrophoretic mobility of some bands were noted between samples. In addition to AMP, several minor polypeptides were also present in all the genotypes, and variations were seen in these as well. Regardless of the genotype, AMP was recognized in Western blots by rabbit polyclonal anti-AMP antibodies, mouse monoclonal anti-AMP antibodies (mAbs), and serum IgE from patients displaying strong serum anti-almond IgE reactivity. As with protein staining results, antibody reactivity also revealed common patterns but displayed some variation between samples. An anti-AMP inhibition ELISA was used to quantify and compare aqueous extracts for various samples. All samples (n = 60) reacted in this assay with a mean +/- standard deviation (sigma n) = 0.82 +/- 0.18 when compared to reference aqueous extract from Nonpareil designated as 1.0. PMID:11308365

  13. A novel Ca2+-activated protease from germinating Vigna radiata seeds and its role in storage protein mobilization.

    PubMed

    Khan, Sadaf; Verma, Giti; Sharma, Samir

    2010-07-15

    Calcium (Ca(2+))-dependent/activated proteases make decisive cleavages in proteins, affecting their further degradation/activation. Few such Ca(2+)-dependent proteases have been reported from plants, and none during germination-related events. Seeds are woken up from their quiescent state upon imbibition of water. The subsequent process of germination is strongly influenced by hormones (mainly gibberellins) and light, with both resulting in change in intracellular Ca(2+). We have investigated the effect of Ca(2+) on protease activity in extracts prepared from dry Vigna radiata (L.) Wilczec seeds and cotyledons 4, 24, 48 and 72h post-imbibition. Ca(2+)-activated protease activity is present at a very low level in dry seeds, rises with imbibition and peaks 24h post-imbibition. Subsequently, the activity rapidly declines, even as total protease activity continues to rise. Calcium activation of proteolysis was reversed by ethylene diamine tetraacetic acid (EDTA), ethylene glycol-bis (2-aminoethylether)-N,N,N',N'-tetraacetic acid (EGTA), 1,10, phenanthroline, chlorpromazine and by beta-mercaptoethanol in a concentration-dependent manner. Protease activity was also inhibited by para chloro mercuribenzoate (pCMB) and l-trans-epoxysuccinyl-leucylamido(4-guanidino) butane (E 64), while phenyl methyl sulfonyl fluoride (PMSF) and pepstatin did not effect Ca(2+) activation. The protease could be separated from the calmodulin fraction by size-exclusion chromatography, while retaining its ability for Ca(2+) activation, excluding the possibility of activation through calmodulin-based pathways. The presence of a Ca(2+)-activated protease in the cotyledons suggests its role in a predetermined program of germination involving elevation of cytosolic Ca(2+) levels during germination. This protease could be an important enzyme interfacing cytoplasmic signaling events and initiation of storage protein mobilization during seed germination.

  14. Mobile laboratory measurements of atmospheric emissions from agriculture, oil, and natural gas activities in northeastern Colorado

    NASA Astrophysics Data System (ADS)

    Eilerman, S. J.; Peischl, J.; Neuman, J. A.; Ryerson, T. B.; Wild, R. J.; Perring, A. E.; Brown, S. S.; Aikin, K. C.; Holloway, M.; Roberts, O.

    2014-12-01

    Atmospheric emissions from agriculture are important to air quality and climate, yet their representation in inventories is incomplete. Increased fertilizer use has lead to increased emissions of nitrogen compounds, which can adversely affect ecosystems and contribute to the formation of fine particulates. Furthermore, extraction and processing of oil and natural gas continues to expand throughout northeastern Colorado; emissions from these operations require ongoing measurement and characterization. This presentation summarizes initial data and analysis from a summer 2014 campaign to study emissions of nitrogen compounds, methane, and other species in northeastern Colorado using a new mobile laboratory. A van was instrumented to measure NH3, N2O, NOx, NOy, CH4, CO, CO2, O3, and bioaerosols with high time resolution. By sampling in close proximity to a variety of emissions sources, the mobile laboratory facilitated accurate source identification and quantification of emissions ratios. Measurements were obtained near agricultural sites, natural gas and oil operations, and other point sources. Additionally, extensive measurements were obtained downwind from urban areas and along roadways. The relationship between ammonia and other trace gases is used to characterize sources and constrain emissions inventories.

  15. Theory of activated glassy relaxation, mobility gradients, surface diffusion, and vitrification in free standing thin films

    SciTech Connect

    Mirigian, Stephen E-mail: smirigian@gmail.com; Schweizer, Kenneth S. E-mail: smirigian@gmail.com

    2015-12-28

    We have constructed a quantitative, force level, statistical mechanical theory for how confinement in free standing thin films introduces a spatial mobility gradient of the alpha relaxation time as a function of temperature, film thickness, and location in the film. The crucial idea is that relaxation speeds up due to the reduction of both near-surface barriers associated with the loss of neighbors in the local cage and the spatial cutoff and dynamical softening near the vapor interface of the spatially longer range collective elasticity cost for large amplitude hopping. These two effects are fundamentally coupled. Quantitative predictions are made for how an apparent glass temperature depends on the film thickness and experimental probe technique, the emergence of a two-step decay and mobile layers in time domain measurements, signatures of confinement in frequency-domain dielectric loss experiments, the dependence of film-averaged relaxation times and dynamic fragility on temperature and film thickness, surface diffusion, and the relationship between kinetic experiments and pseudo-thermodynamic measurements such as ellipsometry.

  16. Crystallization kinetics and molecular mobility of an amorphous active pharmaceutical ingredient: A case study with Biclotymol.

    PubMed

    Schammé, Benjamin; Couvrat, Nicolas; Malpeli, Pascal; Delbreilh, Laurent; Dupray, Valérie; Dargent, Éric; Coquerel, Gérard

    2015-07-25

    The present case study focuses on the crystallization kinetics and molecular mobility of an amorphous mouth and throat drug namely Biclotymol, through differential scanning calorimetry (DSC), temperature resolved X-ray powder diffraction (TR-XRPD) and hot stage microscopy (HSM). Kinetics of crystallization above the glass transition through isothermal and non-isothermal cold crystallization were considered. Avrami model was used for isothermal crystallization process. Non-isothermal cold crystallization was investigated through Augis and Bennett model. Differences between crystallization processes have been ascribed to a site-saturated nucleation mechanism of the metastable form, confirmed by optical microscopy images. Regarding molecular mobility, a feature of molecular dynamics in glass-forming liquids as thermodynamic fragility index m was determined through calorimetric measurements. It turned out to be around m=100, describing Biclotymol as a fragile glass-former for Angell's classification. Relatively long-term stability of amorphous Biclotymol above Tg was analyzed indirectly by calorimetric monitoring to evaluate thermodynamic parameters and crystallization behavior of glassy Biclotymol. Within eight months of storage above Tg (T=Tg+2°C), amorphous Biclotymol does not show a strong inclination to crystallize and forms a relatively stable glass. This case study, involving a multidisciplinary approach, points out the importance of continuing looking for stability predictors.

  17. A single amino acid mutation alters the capsid protein electrophoretic double-band phenotype of the Plum pox virus strain PPV-Rec.

    PubMed

    Subr, Z W; Kamencayová, M; Nováková, S; Nagyová, A; Nosek, J; Glasa, M

    2010-07-01

    Plum pox virus (PPV) isolates differ by their capsid protein (CP) mobility in SDS-PAGE. These electrophoretic phenotypes are likely to result from post-translational modifications of the CP. We demonstrated that the CP mobility was solely determined by the CP N-terminal region. Sequence comparison pinpointed a possible role of mutations at position 66 in determining the CP phenotype of PPV-Rec isolates. Site-directed mutagenesis of a chimeric clone demonstrated that Gly(66) in the CP resulted in the double-band phenotype, while Arg(66) led to a single-band CP pattern, possibly by preventing the phosphorylation of a nearby Ser residue by steric hindrance.

  18. Design and Test of a Hybrid Foot Force Sensing and GPS System for Richer User Mobility Activity Recognition

    PubMed Central

    Zhang, Zelun; Poslad, Stefan

    2013-01-01

    Wearable and accompanied sensors and devices are increasingly being used for user activity recognition. However, typical GPS-based and accelerometer-based (ACC) methods face three main challenges: a low recognition accuracy; a coarse recognition capability, i.e., they cannot recognise both human posture (during travelling) and transportation mode simultaneously, and a relatively high computational complexity. Here, a new GPS and Foot-Force (GPS + FF) sensor method is proposed to overcome these challenges that leverages a set of wearable FF sensors in combination with GPS, e.g., in a mobile phone. User mobility activities that can be recognised include both daily user postures and common transportation modes: sitting, standing, walking, cycling, bus passenger, car passenger (including private cars and taxis) and car driver. The novelty of this work is that our approach provides a more comprehensive recognition capability in terms of reliably recognising both human posture and transportation mode simultaneously during travel. In addition, by comparing the new GPS + FF method with both an ACC method (62% accuracy) and a GPS + ACC based method (70% accuracy) as baseline methods, it obtains a higher accuracy (95%) with less computational complexity, when tested on a dataset obtained from ten individuals. PMID:24189333

  19. Design and test of a hybrid foot force sensing and GPS system for richer user mobility activity recognition.

    PubMed

    Zhang, Zelun; Poslad, Stefan

    2013-11-01

    Wearable and accompanied sensors and devices are increasingly being used for user activity recognition. However, typical GPS-based and accelerometer-based (ACC) methods face three main challenges: a low recognition accuracy; a coarse recognition capability, i.e., they cannot recognise both human posture (during travelling) and transportation mode simultaneously, and a relatively high computational complexity. Here, a new GPS and Foot-Force (GPS + FF) sensor method is proposed to overcome these challenges that leverages a set of wearable FF sensors in combination with GPS, e.g., in a mobile phone. User mobility activities that can be recognised include both daily user postures and common transportation modes: sitting, standing, walking, cycling, bus passenger, car passenger (including private cars and taxis) and car driver. The novelty of this work is that our approach provides a more comprehensive recognition capability in terms of reliably recognising both human posture and transportation mode simultaneously during travel. In addition, by comparing the new GPS + FF method with both an ACC method (62% accuracy) and a GPS + ACC based method (70% accuracy) as baseline methods, it obtains a higher accuracy (95%) with less computational complexity, when tested on a dataset obtained from ten individuals.

  20. Important parameters in semi-dry electrophoretic transfer.

    PubMed

    Jacobson, G; Kårsnäs, P

    1990-01-01

    The efficiency of semi-dry electrophoretic transfer after sodium dodecyl sulfate (SDS)-electrophoresis using PhastGel media was investigated in a model system using three isotope labelled proteins. To give a full picture of the blotting process the amount of protein present in the gel, membranes, and filter papers was determined after different transfer times. The influence of the transfer buffer, commonly used additives such as methanol and SDS, and several different immobilizing matrices was investigated. Soybean trypsin inhibitor, bovine serum albumin, and ferritin were used as model proteins to study the effect of size on transfer efficiency. Basically, all three stages of the blotting process decide the result; the elution of protein from the gel, the immobilization of protein to the membrane, and the loss of material from the membrane during transfer. A theoretical explanation for the observed poor binding to a second membrane is discussed. Our results show that the buffer composition has little influence on the efficiency of transfer from the gel, but can be significant to the binding capacity of the membrane. In all experiments performed, there was never one moment during the transfer when all protein was eluted from the gel and simultaneously still bound to the membrane. The highest recovery in the membrane was obtained at different time intervals for different proteins. This indicates that quantitative transfer procedures cannot be generalized. However, obtaining an optimal method for reliable quantification of a specific protein or group of proteins is possible. For general protein staining of nitrocellulose and polyvinylidene difluoride membranes, a highly sensitive silver staining method requiring only 15 min has been used. PMID:1690643

  1. Automated Personalized Feedback for Physical Activity and Dietary Behavior Change With Mobile Phones: A Randomized Controlled Trial on Adults

    PubMed Central

    Pfammatter, Angela; Zhang, Mi; Spring, Bonnie; Choudhury, Tanzeem

    2015-01-01

    Background A dramatic rise in health-tracking apps for mobile phones has occurred recently. Rich user interfaces make manual logging of users’ behaviors easier and more pleasant, and sensors make tracking effortless. To date, however, feedback technologies have been limited to providing overall statistics, attractive visualization of tracked data, or simple tailoring based on age, gender, and overall calorie or activity information. There are a lack of systems that can perform automated translation of behavioral data into specific actionable suggestions that promote healthier lifestyle without any human involvement. Objective MyBehavior, a mobile phone app, was designed to process tracked physical activity and eating behavior data in order to provide personalized, actionable, low-effort suggestions that are contextualized to the user’s environment and previous behavior. This study investigated the technical feasibility of implementing an automated feedback system, the impact of the suggestions on user physical activity and eating behavior, and user perceptions of the automatically generated suggestions. Methods MyBehavior was designed to (1) use a combination of automatic and manual logging to track physical activity (eg, walking, running, gym), user location, and food, (2) automatically analyze activity and food logs to identify frequent and nonfrequent behaviors, and (3) use a standard machine-learning, decision-making algorithm, called multi-armed bandit (MAB), to generate personalized suggestions that ask users to either continue, avoid, or make small changes to existing behaviors to help users reach behavioral goals. We enrolled 17 participants, all motivated to self-monitor and improve their fitness, in a pilot study of MyBehavior. In a randomized two-group trial, investigators randomly assigned participants to receive either MyBehavior’s personalized suggestions (n=9) or nonpersonalized suggestions (n=8), created by professionals, from a mobile phone

  2. Characterization and film properties of electrophoretically deposited nanosheets of anionic titanate and cationic MgAl-layered double hydroxide.

    PubMed

    Matsuda, Atsunori; Sakamoto, Hisatoshi; Mohd Nor, Mohd Arif Bin; Kawamura, Go; Muto, Hiroyuki

    2013-02-14

    Anionic hydrated titanate (H(n)TiO(m): HTO) nanosheets and cationic magnesium-aluminum layered double hydroxide (Mg-Al LDH) nanosheets were electrophoretically deposited on positively and negatively charged indium tin oxide (ITO)-coated glass substrates, respectively. The HTO nanosheets and Mg-Al LDH nanosheets obtained were identified in neutral water as H(2)Ti(4)O(9)·nH(2)O with a ζ-potential of -23 mV and Mg(6)Al(2)(OH)(18)·4.5H(2)O with a ζ-potential of +41 mV, respectively. Dense and smooth HTO and Mg-Al LDH films with layered structures with thicknesses of about 10-15 μm were prepared in 300 s at 7.5 V by electrophoretic deposition (EPD) from the nanosheet suspensions. Both EPD HTO and LDH films showed elasticity because of their layered laminate structures. The HTO thick films demonstrated large adsorption properties and high photocatalytic activity, while the Mg-Al LDH thick films showed relatively high ionic conductivity of 10(-5) S cm(-1) at 80 °C and 80% relative humidity.

  3. Electrophoretic deposition of multi-walled carbon nanotube on a stainless steel electrode for use in sediment microbial fuel cells.

    PubMed

    Song, Tian-Shun; Peng-Xiao; Wu, Xia-Yuan; Zhou, Charles C

    2013-07-01

    Sediment microbial fuel cells (SMFCs) could be used as power sources and one type of new technology for the removal of organic matters in sediments. In order to improve electrode materials and enhance their effect on the performance, we deposited multi-walled carbon nanotube (MWNT) on stainless steel net (SSN). Electrophoretic deposition technique as a method with low cost, process simplicity, and thickness control was used for this electrode modification and produced this novel SSN-MWNT electrode. The performances of SMFCs with SSN-MWNT as electrode were investigated. The results showed that the maximum power density of SMFC with SSN-MWNT cathode was 31.6 mW m(-2), which was 3.2 times that of SMFC with an uncoated stainless steel cathode. However, no significant increase in the maximum power density of SMFC with SSN-MWNT anode was detected. Further electrochemical analysis showed that when SSN-MWNT was used as the cathode, the cathodic electrochemical activity and oxygen reduction rate were significantly improved. This study demonstrates that the electrophoretic deposition of carbon nanotubes on conductive substrate can be applied for improving the performance of SMFC.

  4. School Travel Planning: Mobilizing School and Community Resources to Encourage Active School Transportation

    ERIC Educational Resources Information Center

    Buliung, Ron; Faulkner, Guy; Beesley, Theresa; Kennedy, Jacky

    2011-01-01

    Background: Active school transport (AST), school travel using an active mode like walking, may be important to children's overall physical activity. A "school travel plan" (STP) documents a school's transport characteristics and provides an action plan to address school and neighborhood barriers to AST. Methods: We conducted a pilot STP…

  5. Attitudes and perceptions of patients on the kidney transplant waiting list toward mobile health–delivered physical activity programs

    PubMed Central

    Sieverdes, John C.; Raynor, Phyllis A.; Armstrong, Tracy; Jenkins, Carolyn H.; Sox, Luke R.; Treiber, Frank A.

    2016-01-01

    Context Dialysis patients’ lifestyles are associated with low levels of physical activity, increasing the chances of being removed from kidney waiting lists or dying while awaiting transplant because of increased cardiovascular risk factors and deteriorating health conditions. Personalized mobile health (mHealth) delivered programs may support their engagement in healthier lifestyles, maintain transplant eligibility, and reduce premature mortality. Objective To explore barriers and perceptions of physical activity behaviors and gauge interest in using mHealth in a physical activity wellness program for dialysis patients on the kidney transplant waiting list. Participants and Design In-depth key informant interviews were conducted with 22 randomly selected dialysis patients during dialysis treatment in an urban Southeastern coastal city. A theory-guided community-based participatory research approach was used to develop the interview content. Constructivist grounded theory guided the data analysis using NVIVO 10 (QSR Int). The 32-item checklist from the Consolidated Criteria for Reporting Qualitative Studies was used in the qualitative reporting. Results Dialysis patients had a mean age of 46 (SD, 10.7) years, 45% were female, and 82% were African American. Their mean duration on transplant waiting lists was 6.7 (SD 4.3) years, and 73% owned smartphones. After saturation was reached, predominant themes included (1) physical activity was perceived as optional, (2) social support both encouraged and limited physical activity, (3) chronic stress and coping influenced physical activity, (4) spirituality provided strength to engage in physical activity, (5) self-care management practices varied considerably, and (6) high interest (95%) for using mHealth to promote physical activity was found. Patients preferred their home and neighborhood environments to intradialytic settings for engaging in physical activity. PMID:25758797

  6. Mobile Learning Using Mobile Phones

    ERIC Educational Resources Information Center

    Vicente, Paula

    2013-01-01

    The participation in mobile learning programs is conditioned by having/using mobile communication technology. Those who do not have or use such technology cannot participate in mobile learning programs. This study evaluates who are the most likely participants of mobile learning programs by examining the demographic profile and mobile phone usage…

  7. Involvement of Nitric Oxide on Calcium Mobilization and Arachidonic Acid Pathway Activation during Platelet Aggregation with different aggregating agonists

    PubMed Central

    Banerjee, Debipriya; Mazumder, Sahana; Kumar Sinha, Asru

    2016-01-01

    Platelet aggregation by different aggregating agonists is essential in the normal blood coagulation process, the excess of which caused acute coronary syndrome (ACS). In all cases, the activation of arachidonic acid by cycloxygenase was needed for the synthesis of thromboxane A2 (TXA2) but the mechanism of arachidonic acid release in platelets remains obscure. Studies were conducted to determine the role of nitric oxide (NO), if any, on the release of arachidonic acid in platelets. The cytosolic Ca2+ was visualized and quantitated by fluorescent spectroscopy by using QUIN-2. NO was measured by methemoglobin method. Arachidonic acid was determined by HPLC. TXA2 was measured as ThromboxaneB2 (TXB2) by ELISA. Treatment of platelets in platelet-rich plasma (PRP) with different aggregating agents resulted in the inhibition of nitric oxide synthase (NOS) which inhibited the production of NO synthesis and increased TXA2 synthesis. Furthermore, the treatment of washed PRP with different platelet aggregating agents resulted in the increase of [Ca2+] in nM ranges. In contrast, the pre-treatment of washed PRP with aspirin increased platelet NO level and inhibited the Ca2+ mobilization and TXA2 synthesis. These results indicated that the aggregation of platelets by different aggregating agonists was caused by the cytosolic Ca2+ mobilization due to the inhibition of NOS. PMID:27127451

  8. Mobilization of endocrine-disrupting chemicals and estrogenic activity in simulated rainfall runoff from land-applied biosolids.

    PubMed

    Giudice, Ben D; Young, Thomas M

    2011-10-01

    Municipal biosolids are commonly applied to land as soil amendment or fertilizer as a form of beneficial reuse of what could otherwise be viewed as waste. Balanced against this benefit are potential risks to groundwater and surface water quality from constituents that may be mobilized during storm events. The objective of the present study was to characterize the mobilization of selected endocrine-disrupting compounds, heavy metals, and total estrogenic activity in rainfall runoff from land-applied biosolids. Rainfall simulations were conducted on soil plots amended with biosolids. Surface runoff and leachate was collected and analyzed for the endocrine-disrupting compounds bisphenol A, 17α-ethynylestradiol, triclocarban, triclosan, octylphenol, and nonylphenol; a suite of 16 metals; and estrogenic activity via the estrogen receptor-mediated chemical activated luciferase gene expression (ER-CALUX) bioassay. Triclocarban (2.3-17.3 ng/L), triclosan (<51-309 ng/L), and octylphenol (<4.9-203 ng/L) were commonly detected. Chromium (2.0-22 µg/L), Co (2.5-10 µg/L), Ni (28-235 µg/L), Cu (14-110 µg/L), As (1.2-2.7 µg/L), and Se (0.29-12 µg/L) were quantifiable over background levels. Triclosan, Ni, and Cu were detected at levels that might pose some risk to aquatic life, though levels of metals in the biosolids were well below the maximum allowable regulatory limits. The ER-CALUX results were mostly explained by background bisphenol A contamination and octylphenol in runoff, although unknown contributors or matrix effects were also found. PMID:21786314

  9. Mobilization of endocrine-disrupting chemicals and estrogenic activity in simulated rainfall runoff from land-applied biosolids.

    PubMed

    Giudice, Ben D; Young, Thomas M

    2011-10-01

    Municipal biosolids are commonly applied to land as soil amendment or fertilizer as a form of beneficial reuse of what could otherwise be viewed as waste. Balanced against this benefit are potential risks to groundwater and surface water quality from constituents that may be mobilized during storm events. The objective of the present study was to characterize the mobilization of selected endocrine-disrupting compounds, heavy metals, and total estrogenic activity in rainfall runoff from land-applied biosolids. Rainfall simulations were conducted on soil plots amended with biosolids. Surface runoff and leachate was collected and analyzed for the endocrine-disrupting compounds bisphenol A, 17α-ethynylestradiol, triclocarban, triclosan, octylphenol, and nonylphenol; a suite of 16 metals; and estrogenic activity via the estrogen receptor-mediated chemical activated luciferase gene expression (ER-CALUX) bioassay. Triclocarban (2.3-17.3 ng/L), triclosan (<51-309 ng/L), and octylphenol (<4.9-203 ng/L) were commonly detected. Chromium (2.0-22 µg/L), Co (2.5-10 µg/L), Ni (28-235 µg/L), Cu (14-110 µg/L), As (1.2-2.7 µg/L), and Se (0.29-12 µg/L) were quantifiable over background levels. Triclosan, Ni, and Cu were detected at levels that might pose some risk to aquatic life, though levels of metals in the biosolids were well below the maximum allowable regulatory limits. The ER-CALUX results were mostly explained by background bisphenol A contamination and octylphenol in runoff, although unknown contributors or matrix effects were also found.

  10. The Presence of a Stable Block bounded by Active Zones (Mobile Belts) in the southwestern North American Proterozoic craton

    NASA Astrophysics Data System (ADS)

    Goodell, P.; Martinez P, C.; Mahar, M. A.

    2014-12-01

    Bouguer gravity data, initial Sr isotope values, zircon U-Pb, and multiple occurrences of felsic Proterozoic rocks, have revealed an elevated, less deformed, felsic cratonic block in the northern Mexico. The block is situated in western Chihuahua and is bounded by active zones or mobile belts on three sides, and is here referred to as the Western Chihuahua Cratonic Block (WCCB). Bouguer gravity data clearly indicate a region of a highly negative anomaly (< -200 mgal) in contrast to adjoining areas. The region is large and the anomaly is relatively smooth over broad areas; the WCCB appears as a smaller version of the Colorado Plateau. The block is characterized by high initial Sr isotope ratios (<0.706). Several occurrences of Proterozoic rocks are located within or next to the WCCB, and they reveal the character of the Bouguer anomaly. On the east, at Los Filtros, Proterozoic rocks crop out in a basement cored uplift interpreted to having been derived from the WCCB during the Ouachita orogeny. At Sierra La Mojina boulders of 1.1 Ga granites are found in Permian conglomerates. And at Basasiachic, xenoliths of 1.1 Ga granites are present in ash flow tuffs. Establishment of the Precambrian character of the WCCB is of importance, and these multiple occurrences are evidence. Prior studies of the Sierra Madre Occidental suggest that the region was uplifted because of a vast Cenozoic batholith presumed to lie under the SLIP (Silicic Large Igneous Province), the Upper Volcanic Series. The present study challenges that conclusion and maintains the SMO is underlain by Proterozoic silicic crust. The geology of age dated samples supports this. The WCCB is surrounded on three sides by Active Zones or Mobile Belts, which have been active extensional and translational zones periodically over a long period of time. On the east are the Paleozoic Pedrogosa Basin, Mesozoic Chihuahua Trough and Cenozoic Rio Grande Rift, the first two of which also continue around the northern border

  11. Photoelectrochemical Behavior of Electrophoretically Deposited Hematite Thin Films Modified with Ti(IV).

    PubMed

    Dalle Carbonare, Nicola; Boaretto, Rita; Caramori, Stefano; Argazzi, Roberto; Dal Colle, Maurizio; Pasquini, Luca; Bertoncello, Renzo; Marelli, Marcello; Evangelisti, Claudio; Bignozzi, Carlo Alberto

    2016-01-01

    Doping hematite with different elements is a common strategy to improve the electrocatalytic activity towards the water oxidation reaction, although the exact effect of these external agents is not yet clearly understood. Using a feasible electrophoretic procedure, we prepared modified hematite films by introducing in the deposition solution Ti(IV) butoxide. Photoelectrochemical performances of all the modified electrodes were superior to the unmodified one, with a 4-fold increase in the photocurrent at 0.65 V vs. SCE in 0.1 M NaOH (pH 13.3) for the 5% Ti-modified electrode, which was the best performing electrode. Subsequent functionalization with an iron-based catalyst led, at the same potential, to a photocurrent of ca. 1.5 mA·cm(-2), one of the highest achieved with materials based on solution processing in the absence of precious elements. AFM, XPS, TEM and XANES analyses revealed the formation of different Ti(IV) oxide phases on the hematite surface, that can reduce surface state recombination and enhance hole injection through local surface field effects, as confirmed by electrochemical impedance analysis. PMID:27447604

  12. Highly sensitive microscale in vivo sensor enabled by electrophoretic assembly of nanoparticles for multiple biomarker detection.

    PubMed

    Malima, Asanterabi; Siavoshi, Salome; Musacchio, Tiziana; Upponi, Jaydev; Yilmaz, Cihan; Somu, Sivasubramanian; Hartner, William; Torchilin, Vladimir; Busnaina, Ahmed

    2012-11-21

    This paper describes a microscale in vivo sensor platform device for the simultaneous detection of multiple biomarkers. We designed the polymer-based biosensors incorporating multiple active isolated areas, as small as 70 μm × 70 μm, for antigen detection. The fabrication approach involved conventional micro- and nano-fabrication processes followed by site-specific electrophoretic directed assembly of antibody-functionalized nanoparticles. To ensure precise and large-scale manufacturing of these biosensors, we developed a semi-automated system for the attachment of the 250-μm biosensor to a 300-μm catheter probe. Our fabrication and post-processing procedures should enable large-scale production of such biosensor devices at lower manufacturing cost. The principle of detection with these biosensors involved a simple fluorescence-based enzyme-linked immunosorbent assay. These biosensors exhibit high selectivity (ability to selectively detect multiple biomarkers of different diseases), specificity (ability to target generic to specific disease biomarkers), rapid antigen uptake, and low detection limits (for carcinoembryonic antigen, 31.25 pg mL(-1); for nucleosomes, 62.5 pg mL(-1)), laying the foundation for potential early detection of various diseases. PMID:22983480

  13. Fast immuno-labeling by electrophoretically driven infiltration for intact tissue imaging

    PubMed Central

    Li, Jun; Czajkowsky, Daniel M.; Li, Xiaowei; Shao, Zhifeng

    2015-01-01

    Recently developed tissue clearing techniques, where the tissue is embedded within a hydrogel, have revolutionized our ability to resolve fine cellular structures in nearly intact tissues. However, the slow rate of penetration of antibodies within this hydrogel-tissue matrix has become a significantly limiting factor in many experiments, as thick tissues often require weeks to months to be adequately labeled. Increasing the pore size of this matrix has been investigated as a possible solution, but with only modest success. Here, we have systematically examined the diffusional behavior of antibodies and other typically used immuno-labels within this hydrogel-tissue matrix and, surprisingly, found that infiltration occurs at rates similar to those of diffusion in free solution. Therefore, changing the pore size of the matrix would be expected to afford only limited improvement and, instead, some means of active transport is necessary. We show that an electrophoretically-driven approach decreases the delivery time of antibodies by more than 800-fold over simple diffusion, without incurring structural damage. These results, together with the high quality of the images obtained with this method, demonstrate the advantage of this approach, thus significantly broadening the practical range of samples that can now be investigated by whole-mount tissue clearing methods. PMID:26013317

  14. High-mobility thin film transistors with neodymium-substituted indium oxide active layer

    SciTech Connect

    Lin, Zhenguo; Lan, Linfeng Xiao, Peng; Sun, Sheng; Li, Yuzhi; Song, Wei; Gao, Peixiong; Wang, Lei; Ning, Honglong; Peng, Junbiao

    2015-09-14

    Thin-film transistors (TFTs) with neodymium-substituted indium oxide (InNdO) channel layer were demonstrated. The structural properties of the InNdO films as a function of annealing temperature have been analyzed using X-ray diffraction and transmission electron microscopy. The InNdO thin films showed polycrystalline nature when annealed at 450 °C with a lattice parameter (cubic cell) of 10.255 Å, which is larger than the cubic In{sub 2}O{sub 3} film (10.117 Å). The high-resolution transmission electron microscopy and energy dispersive X-ray spectroscopy showed that no Nd{sub 2}O{sub 3} clusters were found in the InNdO film, implying that Nd was incorporated into the In{sub 2}O{sub 3} lattice. The InNdO TFTs annealed at 450 °C exhibited more excellent electrical properties with a high mobility of 20.4 cm{sup 2} V{sup −1} s{sup −1} and better electric bias stability compared to those annealed at 300 °C, which was attributed to the reduction of the scattering centers and/or charge traps due to the decrease of the |Nd3d{sub 5/2}{sup 5}4f{sup 4}O2p{sup −1}〉 electron configuration.

  15. LYAR promotes colorectal cancer cell mobility by activating galectin-1 expression

    PubMed Central

    Li, Zhuchen; Wu, Xiao-Bin; Wang, Ying; Wang, Yadong; Nie, Min; Huang, Feifei; Ju, Junyi; Ma, Chi; Tan, Renxiang; Zen, Ke; Zhang, Chen-Yu; Fu, Keqin; Chen, Yu-Gen; Wang, Ming-Rong; Zhao, Quan

    2015-01-01

    Colorectal cancer (CRC) is one of the leading causes of cancer-related death worldwide. However, the molecular mechanisms of CRC pathogenesis are not fully understood. In this study, we report the characterization of LYAR (Ly-1 antibody reactive clone) as a key regulator of the migration and invasion of human CRC cells. Immunohistochemistry analysis demonstrated that LYAR is expressed at a higher level in metastatic CRC tissues. We found that LYAR promoted the migratory and invasive capabilities of CRC cells. Gene expression profile analysis of CRC cells showed that LGALS1, which encodes the galectin-1 protein, was a potential target of LYAR. The ChIP assay and gene reporter assays indicated that LYAR directly bound to the LGALS1 promoter. The ectopic expression of galectin-1 partially restored the mobile potential of LYAR knocked-down cells, which suggests that galectin-1 contributed to the LYAR-promoted cell migration and invasion of CRC cells. Thus, this study revealed a novel mechanism by which the transcription factor LYAR may promote tumor cell migration and invasion by upregulating galectin-1 gene expression in CRC. PMID:26413750

  16. High mobility group box 1 induced human lung myofibroblasts differentiation and enhanced migration by activation of MMP-9.

    PubMed

    Lee, Chen-Chen; Wang, Chien-Neng; Lee, Yueh-Lun; Tsai, Yi-Ru; Liu, Jau-Jin

    2015-01-01

    High mobility group box 1 (HMGB1) is a nuclear protein that involves the binding with DNA and influences chromatin regulation and transcription. HMGB1 is also a cytokine that can activate monocytes and neutrophils involved in inflammation. In this study, we investigated the role of HMGB1 on cellular activation using human fibroblast cell line WI-38. After treatment with 1, 10, and 100 ng/mL of HMGB1 for 24 h, we did not find obviously cytotoxicity and cellular proliferation of WI-38 cells by MTT and BrdU incorporation assay, respectively. However, we found that treatment with 10 and 100 ng/mL of HMGB1 induced the differentiation of lung fibroblasts into myofibroblasts and myofibroblasts showed higher migration ability through activation of matrix metalloproteinase (MMP)-9 activation. To delineate the mechanism underlying HMGB1-induced cellular migration, we examined HMGB1-induced mitogen activated protein kinases (MAPKs), including extracellular signal related kinase (ERK), c-Jun N-terminal kinase (JNK), and p38 mitogen activated protein kinase (p38) phosphorylation, as well as nuclear factor (NF)-κB nuclear translocation. Using specific inhibitors and shRNAs of protein kinases, we observed that repression of ERK, JNK, p38, and NF-κB all inhibited HMGB1-induced cellular differentiation, migration and MMP-9 activation in WI-38 cells. In addition, knocking down of RAGE but not TLR2 and TLR4 by shRNAs attenuated HMGB1-induced myofibroblast differentiation and migration. In conclusion, our study demonstrated that HMGB1 induced lung fibroblasts' differentiation into myofibroblasts and enhanced cell migration through induction of MMP-9 activation and the RAGE-MAPK and NF-κB interaction signaling pathways. Targeting HMGB1 might be a potential therapeutic approach for alleviation of airway remodeling seen in chronic airway inflammatory diseases.

  17. Synthesis of functionally graded materials via electrophoretic deposition and sintering

    NASA Astrophysics Data System (ADS)

    Wang, Xuan

    In this research, both the experiments and the modeling aspects of the net-shape fabrication of Functionally Graded Materials (FGM) by Electrophoretic Deposition (EPD) and consecutive sintering have been investigated. In order to obtain FGMs with desired final shape and properties, the issues regarding the shape evolution during sintering, the optimization of initial properties and composition profiles, and the fabrication of green components by EPD have been analyzed. In order to fabricate FGMs by the proposed technological sequence (EPD with the following sintering), the initial shape has to be optimized prior to sintering. In this research, the formulations to simulate sintering of an FGM were developed based on the continuum theory of sintering. A finite element sintering-modeling subroutine has been created and linked to the commercial finite element package ABAQUS. The shape changes of FGM disks during sintering were simulated. In order to obtain the desired final shape after sintering, an inverse modeling methodology was developed to optimize the initial shape. In order to fabricate the optimized initial shape of a green FGM specimen determined by the inverse continuum modeling of sintering, EPD of a number of FGMs was investigated. The FGM green specimens made of Al2O 3 and ZrO2 with the initial shape predicted by the inverse modeling, were deposited using self-designed equipments. The acetone-based suspension with n-butylamine as a particle-charging additive was used. The comparison of the shape between the sintered and the green FGM indicated that the developed experimental-theoretical methodology provided a reliable solution for near net shaping of complex 3-D FGM components. Other applications of EPD, such as in electronic packaging materials and zeolites, were also investigated. In order to fabricate functionally graded materials based on aligned porous structures, unidirectional freezing followed by freeze-drying and sintering has been investigated

  18. Activation of Plant Innate Immunity by Extracellular High Mobility Group Box 3 and Its Inhibition by Salicylic Acid

    PubMed Central

    Choi, Hyong Woo; Manohar, Murli; Manosalva, Patricia; Tian, Miaoying; Moreau, Magali; Klessig, Daniel F.

    2016-01-01

    Damage-associated molecular pattern molecules (DAMPs) signal the presence of tissue damage to induce immune responses in plants and animals. Here, we report that High Mobility Group Box 3 (HMGB3) is a novel plant DAMP. Extracellular HMGB3, through receptor-like kinases BAK1 and BKK1, induced hallmark innate immune responses, including i) MAPK activation, ii) defense-related gene expression, iii) callose deposition, and iv) enhanced resistance to Botrytis cinerea. Infection by necrotrophic B. cinerea released HMGB3 into the extracellular space (apoplast). Silencing HMGBs enhanced susceptibility to B. cinerea, while HMGB3 injection into apoplast restored resistance. Like its human counterpart, HMGB3 binds salicylic acid (SA), which results in inhibition of its DAMP activity. An SA-binding site mutant of HMGB3 retained its DAMP activity, which was no longer inhibited by SA, consistent with its reduced SA-binding activity. These results provide cross-kingdom evidence that HMGB proteins function as DAMPs and that SA is their conserved inhibitor. PMID:27007252

  19. Energy-efficiency testing activities of the Mobile Energy Laboratory - Semiannual Report: April 1, 1990, Through September 30, 1990

    SciTech Connect

    Parker, G.B.; Currie, J.W.

    1991-03-01

    This report summarizes energy-efficiency testing activities applying the Mobile Energy Laboratory (MEL) testing capabilities during the third and fourth quarters of fiscal year (FY) 1990. The MELs, developed by the US Department of Energy (DOE) Federal Energy Management Program (FEMP), are administered by Pacific Northwest Laboratory (PNL) and the Naval Energy and Environmental Support Activity (NEESA) for energy testing and energy conservation program support functions at federal facilities. MELs are equipped for the on-site evaluation of energy use efficiency. The using agencies principally fund MEL applications, while DOE/FEMP funds program administration and capability enhancement activities. This report fulfills the requirements established in Section 8 of the MEL Use Plan (PNL-6861) for semiannual reporting on energy-efficiency testing activities using the MEL capabilities. The MEL Use Committee, formally established in 1989, developed the MEL Use Plan and meets semiannually to establish priorities for energy-efficient testing applications using the MEL capabilities. This report describes the testing, test results, and suggested courses of action.

  20. Activation of Plant Innate Immunity by Extracellular High Mobility Group Box 3 and Its Inhibition by Salicylic Acid.

    PubMed

    Choi, Hyong Woo; Manohar, Murli; Manosalva, Patricia; Tian, Miaoying; Moreau, Magali; Klessig, Daniel F

    2016-03-01

    Damage-associated molecular pattern molecules (DAMPs) signal the presence of tissue damage to induce immune responses in plants and animals. Here, we report that High Mobility Group Box 3 (HMGB3) is a novel plant DAMP. Extracellular HMGB3, through receptor-like kinases BAK1 and BKK1, induced hallmark innate immune responses, including i) MAPK activation, ii) defense-related gene expression, iii) callose deposition, and iv) enhanced resistance to Botrytis cinerea. Infection by necrotrophic B. cinerea released HMGB3 into the extracellular space (apoplast). Silencing HMGBs enhanced susceptibility to B. cinerea, while HMGB3 injection into apoplast restored resistance. Like its human counterpart, HMGB3 binds salicylic acid (SA), which results in inhibition of its DAMP activity. An SA-binding site mutant of HMGB3 retained its DAMP activity, which was no longer inhibited by SA, consistent with its reduced SA-binding activity. These results provide cross-kingdom evidence that HMGB proteins function as DAMPs and that SA is their conserved inhibitor.

  1. Studies on the introduction and mobility of the maize Activator element in Arabidopsis thaliana and Daucus carota.

    PubMed Central

    Van Sluys, M A; Tempé, J; Fedoroff, N

    1987-01-01

    We have co-transformed carrot (Daucus carota) and Arabidopsis thaliana with an Agrobacterium tumefaciens non-tumorigenic T-DNA carrying the maize transposable element Activator (Ac) and an Agrobacterium rhizogenes Ri T-DNA. We present evidence that the Ac element transposes in transformed root or root-derived callus cultures of both species. We show that fertile plants can be regenerated from transformed, root-derived callus cultures of Arabidopsis, demonstrating the utility of the Ri plasmid for introducing the maize Ac element into plants. We also present evidence that Ac elements that excise from the transforming T-DNA early after transformation continue to be mobile in carrot root cultures. Images Fig. 2. Fig. 3. Fig. 4. Fig. 5. Fig. 6. Fig. 7. PMID:2832144

  2. Hand, belt, pocket or bag: Practical activity tracking with mobile phones.

    PubMed

    Antos, Stephen A; Albert, Mark V; Kording, Konrad P

    2014-07-15

    For rehabilitation and diagnoses, an understanding of patient activities and movements is important. Modern smartphones have built in accelerometers which promise to enable quantifying minute-by-minute what patients do (e.g. walk or sit). Such a capability could inform recommendations of physical activities and improve medical diagnostics. However, a major problem is that during everyday life, we carry our phone in different ways, e.g. on our belt, in our pocket, in our hand, or in a bag. The recorded accelerations are not only affected by our activities but also by the phone's location. Here we develop a method to solve this kind of problem, based on the intuition that activities change rarely, and phone locations change even less often. A hidden Markov model (HMM) tracks changes across both activities and locations, enabled by a static support vector machine (SVM) classifier that probabilistically identifies activity-location pairs. We find that this approach improves tracking accuracy on healthy subjects as compared to a static classifier alone. The obtained method can be readily applied to patient populations. Our research enables the use of phones as activity tracking devices, without the need of previous approaches to instruct subjects to always carry the phone in the same location.

  3. Mobile internet service for self-management of physical activity in people with rheumatoid arthritis: evaluation of a test version

    PubMed Central

    Opava, Christina H; Ahlén, Henrik; Pettersson, Susanne; Åsenlöf, Pernilla

    2016-01-01

    Objectives Life-long adherence to health-enhancing physical activity (PA) is a major challenge for people with rheumatoid arthritis (RA). Our aim was to evaluate the utilisation of and experiences with a RA-specific, mobile internet PA support service, ‘tRAppen’, developed through a co-design process. Methods 28 participants with RA formed 3 web communities and tested tRAppen for 6 weeks. A mixed-method design was used to combine different types of data. Log data and questionnaire data were analysed quantitatively, while data from telephone interviews were analysed with a directed content analysis. Results 25 of the 28 participants used tRAppen. Log data indicated that a majority of them registered their PA, sent likes and posted comments to peers, set personal goals and made exercise plans. tRAppen was rated as easy and fun to use, and fairly informative and supportive for PA, and was highly recommended for people with RA. The interview analysis resulted in the following 6 categories describing the utilisation of and experiences with tRAppen: (1) experiences in general, (2) feasibility of features, (3) value as support for PA, (4) enjoyment, (5) ideas for improvements and (6) additional factors. Conclusions tRAppen is the first co-designed mobile internet service developed specifically for the self-management of PA in people with RA. The results are promising and indicate that tRAppen may be useful for supporting a physically active lifestyle in a subpopulation at certain risk of poor health. It will now be revised, launched and continuously updated in an iterative process involving its future users. PMID:27099777

  4. MOBILIZATION OF ENDOCRINE DISRUPTING CHEMICALS AND ESTROGENIC ACTIVITY IN SIMULATED RAINFALL RUNOFF FROM LAND-APPLIED BIOSOLIDS

    PubMed Central

    Giudice, Ben D.; Young, Thomas M.

    2012-01-01

    Municipal biosolids are commonly applied to land as soil amendment or fertilizer as a form of beneficial reuse of what could otherwise be viewed as waste. Balanced against this benefit are potential risks to groundwater and surface water quality from constituents that may be mobilized during storm events. The objective of the present study was to characterize the mobilization of selected endocrine disrupting compounds (EDCs), heavy metals, and total estrogenic activity in rainfall runoff from land-applied biosolids. Rainfall simulations were conducted on soil plots amended with biosolids. Surface runoff and leachate was collected and analyzed for the EDCs bisphenol A, 17α-ethynylestradiol, triclocarban, triclosan, octylphenol, and nonylphenol; a suite of sixteen metals; and estrogenic activity via the ER-CALUX bioassay. Triclocarban (2.3–17.3 ng/L), triclosan (<51–309 ng/L), and octylphenol (<4.9–203 ng/L) were commonly detected. Chromium (2.0–22 µg/L), cobalt (2.5–10 µg/L), nickel (28–235 µg/L), copper (14–110 µg/L), arsenic (1.2–2.7 µg/L), and selenium (0.29–12 µg/L) were quantifiable over background levels. Triclosan, nickel, and copper were detected at levels that might pose some risk to aquatic life, though levels of metals in the biosolids were well below maximum allowable regulatory limits. ER-CALUX results were mostly explained by background bisphenol A contamination and octylphenol in runoff, though unknown contributors and/or matrix effects were also found. PMID:21786314

  5. Microbiological Analysis of an Active Pilot-Scale Mobile Bioreactor Treating Organic Contaminants

    SciTech Connect

    Brigmon, R.L.

    1997-11-26

    Samples were obtained for microbiological analysis from a granular activated carbon fluidized bed bioreactor (GAC-FBR). This GAC-FBR was in operation at a former manufactured gas plant (MGP) Site in Augusta Georgia for in situ groundwater bioremediation of organics. The samples included contaminated site groundwater, GAC-FBR effluent, and biofilm coated granular activated carbon at 5, 9, and 13 feet within the GAC-FBR column. The objective of this analysis was to correlate contaminant removal with microbiological activity within the GAC-FBR.

  6. Increasing physical activity efficiently: an experimental pilot study of a website and mobile phone intervention.

    PubMed

    Thorsteinsen, Kjærsti; Vittersø, Joar; Svendsen, Gunnvald Bendix

    2014-01-01

    The main objective of this pilot study was to test the effectiveness of an online, interactive physical activity intervention that also incorporated gaming components. The intervention design included an activity planner, progress monitoring, and gamification components and used SMS text as a secondary delivery channel and feedback to improve engagement in the intervention content. Healthy adults (n = 21) recruited through ads in local newspapers (age 35-73) were randomized to the intervention or the control condition. Both groups reported physical activity using daily report forms in four registration weeks during the three-month study: only the experiment condition received access to the intervention. Analyses showed that the intervention group had significantly more minutes of physical activity in weeks five and nine. We also found a difference in the intensity of exercise in week five. Although the intervention group reported more minutes of physical activity at higher intensity levels, we were not able to find a significant effect at the end of the study period. In conclusion, this study adds to the research on the effectiveness of using the Internet and SMS text messages for delivering physical activity interventions and supports gamification as a viable intervention tool.

  7. Increasing physical activity efficiently: an experimental pilot study of a website and mobile phone intervention.

    PubMed

    Thorsteinsen, Kjærsti; Vittersø, Joar; Svendsen, Gunnvald Bendix

    2014-01-01

    The main objective of this pilot study was to test the effectiveness of an online, interactive physical activity intervention that also incorporated gaming components. The intervention design included an activity planner, progress monitoring, and gamification components and used SMS text as a secondary delivery channel and feedback to improve engagement in the intervention content. Healthy adults (n = 21) recruited through ads in local newspapers (age 35-73) were randomized to the intervention or the control condition. Both groups reported physical activity using daily report forms in four registration weeks during the three-month study: only the experiment condition received access to the intervention. Analyses showed that the intervention group had significantly more minutes of physical activity in weeks five and nine. We also found a difference in the intensity of exercise in week five. Although the intervention group reported more minutes of physical activity at higher intensity levels, we were not able to find a significant effect at the end of the study period. In conclusion, this study adds to the research on the effectiveness of using the Internet and SMS text messages for delivering physical activity interventions and supports gamification as a viable intervention tool. PMID:24963290

  8. Electrical characterization of electrophoretically coated aluminum samples for photovoltaic concentrator application

    SciTech Connect

    Sugimura, R.S.; Mon, G.R.; Ross, R.G. Jr.

    1992-10-01

    The practicality of using a thin-film styrene/acrylate copolymer electrophoretic coating to isolate concentrator cells electrically from their surroundings in a photovoltaic concentrator module is assessed. Only the electrical isolation problem was investigated. The approach was to subject various types of EP-coated aluminum specimens to electrical stress testing and to aging tests while monitoring coating electrical resistivity properties. It was determined that, in general, longer processing times--i.e., thicker electrophoretic layers--resulted in better voltage-withstand properties. In particular, a two-minute processing time seemed sufficient to provide the electrical isolation required in photovoltaic concentrator application applications. Even though electrophoretic coatings did not seem to fill voids in porous-anodized aluminum substrates, breakdown voltages generally exceeded hi-pot pass-fail voltage levels with a comfortable margin. 6 refs, 11 figs, 5 tabs.

  9. The cost-effectiveness of the MobileMums intervention to increase physical activity among mothers with young children: a Markov model informed by a randomised controlled trial

    PubMed Central

    Burn, Edward; Barnett, Adrian G; Fjeldsoe, Brianna S; Graves, Nicholas

    2015-01-01

    Objectives To determine the cost-effectiveness of the MobileMums intervention. MobileMums is a 12-week programme which assists mothers with young children to be more physically active, primarily through the use of personalised SMS text-messages. Design A cost-effectiveness analysis using a Markov model to estimate and compare the costs and consequences of MobileMums and usual care. Setting This study considers the cost-effectiveness of MobileMums in Queensland, Australia. Participants A hypothetical cohort of over 36 000 women with a child under 1 year old is considered. These women are expected to be eligible and willing to participate in the intervention in Queensland, Australia. Data sources The model was informed by the effectiveness results from a 9-month two-arm community-based randomised controlled trial undertaken in 2011 and registered retrospectively with the Australian Clinical Trials Registry (ACTRN12611000481976). Baseline characteristics for the model cohort, treatment effects and resource utilisation were all informed by this trial. Main outcome measures The incremental cost per quality-adjusted life year (QALY) of MobileMums compared with usual care. Results The intervention is estimated to lead to an increase of 131 QALYs for an additional cost to the health system of 1.1 million Australian dollars (AUD). The expected incremental cost-effectiveness ratio for MobileMums is 8608 AUD per QALY gained. MobileMums has a 98% probability of being cost-effective at a cost-effectiveness threshold of 64 000 AUD. Varying modelling assumptions has little effect on this result. Conclusions At a cost-effectiveness threshold of 64 000 AUD, MobileMums would likely be a cost-effective use of healthcare resources in Queensland, Australia. Trial registration number Australian Clinical Trials Registry; ACTRN12611000481976. PMID:25926145

  10. Active Social Policy Meets the Discipline of the Australian Marketplace: The Outcomes of Mobile Policies

    ERIC Educational Resources Information Center

    Zoellner, Don

    2016-01-01

    Many advanced market democracies pursue social justice by bundling together a range of programmes represented as active social policy. Northern European exemplars sanction employment as an economic and social citizen's civic obligation, promote lifelong learning and place welfare payments as a last resort. In the United States, market-based…

  11. [Development of a semi-autonomous mobile robot for reactor containments]. 1992 annual summary of activity

    SciTech Connect

    Wehe, D.K.

    1993-02-10

    The University of Michigan reports its progress on this project on a bimonthly or quarterly reporting frequency. As a result, the detailed annual summary of activity is derived from the integration of these progress reports. They are attached here to form a permanent record of the University`s contribution to this program.

  12. Poly(glycidyl methacrylate)/silver nanocomposite microspheres as a radioiodine scavenger: electrophoretic characterisation of carboxyl- and amine-modified particles.

    PubMed

    Macková, Hana; Oukacine, Farid; Plichta, Zdeněk; Hrubý, Martin; Kučka, Jan; Taverna, Myriam; Horák, Daniel

    2014-05-01

    Silver nanoparticles possess potent antibacterial properties and have extremely high affinities to radioiodine. For several applications, it is essential to anchor the nanoparticles to microparticles or solid surfaces to make them insoluble while retaining their unique properties. This current work is related to the design of anionic and cationic macroporous polymer microspheres based on poly(glycidyl methacrylate) (PGMA) obtained using a multistep swelling polymerisation. According to scanning electron microscopy, the microspheres were monodisperse in size and 4.2 μm in diameter. The presence of the carboxyl and amino groups in the PGMA-COOH and PGMA-NH2 microspheres was confirmed by FT-IR spectroscopy. Capillary electrophoresis (CE) and pressure-assisted capillary electrophoresis (PACE) were used to study the electrophoretic behaviour of both types of microparticles. The electrophoretic mobility of the microparticles was changed into ζ potential using Smoluchowski modelling. Finally, silver-containing microspheres were prepared by reducing silver nitrate in the presence of the microspheres, and they proved effective for scavenging radioiodide ions from a model medium.

  13. Comparison of Physical Activity Measures Using Mobile Phone-Based CalFit and Actigraph

    PubMed Central

    Donaire-Gonzalez, David; de Nazelle, Audrey; Seto, Edmund; Mendez, Michelle; Jerrett, Michael

    2013-01-01

    Background Epidemiological studies on physical activity often lack inexpensive, objective, valid, and reproducible tools for measuring physical activity levels of participants. Novel sensing technologies built into smartphones offer the potential to fill this gap. Objective We sought to validate estimates of physical activity and determine the usability for large population-based studies of the smartphone-based CalFit software. Methods A sample of 36 participants from Barcelona, Spain, wore a smartphone with CalFit software and an Actigraph GT3X accelerometer for 5 days. The ease of use (usability) and physical activity measures from both devices were compared, including vertical axis counts (VT) and duration and energy expenditure predictions for light, moderate, and vigorous intensity from Freedson’s algorithm. Statistical analyses included (1) Kruskal-Wallis rank sum test for usability measures, (2) Spearman correlation and linear regression for VT counts, (3) concordance correlation coefficient (CCC), and (4) Bland-Altman plots for duration and energy expenditure measures. Results Approximately 64% (23/36) of participants were women. Mean age was 31 years (SD 8) and mean body mass index was 22 kg/m2 (SD 2). In total, 25/36 (69%) participants recorded at least 3 days with at least 10 recorded hours of physical activity using CalFit. The linear association and correlations for VT counts were high (adjusted R 2=0.85; correlation coefficient .932, 95% CI 0.931-0.933). CCCs showed high agreement for duration and energy expenditure measures (from 0.83 to 0.91). Conclusions The CalFit system had lower usability than the Actigraph GT3X because the application lacked a means to turn itself on each time the smartphone was powered on. The CalFit system may provide valid estimates to quantify and classify physical activity. CalFit may prove to be more cost-effective and easily deployed for large-scale population health studies than other specialized instruments because

  14. Capillary electrophoretic study of thiolated alpha-cyclodextrin-capped gold nanoparticles with tetraalkylammonium ions.

    PubMed

    Paau, Man Chin; Lo, Chung Keung; Yang, Xiupei; Choi, Martin M F

    2009-11-27

    Capillary zone electrophoresis (CZE) has been employed to characterize nanometer-sized thiolated alpha-cyclodextrin-capped gold nanoparticles (alpha-CD-S-AuNPs). The addition of tetrabutylammonium (Bu(4)N(+)) ions to the run buffer greatly narrows the migration peak of alpha-CD-S-AuNP. The optimal run buffer was determined to be 10mM Bu(4)N(+) in 30 mM phosphate buffer at pH 12 and an applied voltage of 15 kV. The effect of various tetraalkylammonium ions on the peak width and electrophoretic mobility (mu(e)) of alpha-CD-S-AuNP was studied in detail. Bu(4)N(+) ions assist in inter-linking the alpha-CD-S-AuNPs and narrowing the migration peak in CZE. This observation can be explained by the fact that each Bu(4)N(+) ion can simultaneously interact with several hydrophobic cavities of the surface-attached alpha-CDs on AuNPs. The TEM images show that alpha-CD-S-AuNPs with Bu(4)N(+) are linked together but in the absence of Bu(4)N(+), they are more dispersed. The migration mechanism in CZE is based on the formation of inclusion complexes between Bu(4)N(+) and alpha-CD-S-AuNPs which induces changes in the charge-to-size ratio of alpha-CD-S-AuNPs and mu(e). An inverse linear relationship (r(2)>0.998) exists between the mu(e) and size of alpha-CD-S-AuNPs in the core range 1.4-4.1 nm. The CZE analyses are rapid with migration time less than 4 min. A few nanoliters of each of the alpha-CD-S-AuNP samples were injected hydrodynamically at 0.5 psi for 5s. Our work confirms that CZE is an efficient tool for characterizing the sizes of alpha-CD-S-AuNPs using Bu(4)N(+) ions. PMID:19853853

  15. Doped LaFeO3 as SOFC Catalysts: Control of Oxygen Mobility Oxidation Activity

    SciTech Connect

    N Lakshminarayanan; J Kuhn; S Rykov; J Millet; U Ozkan; T Rao; J Smedley; E Wang; E Muller; et al.

    2011-12-31

    The bulk structure and surface properties of Fe-based perovskite-type oxides with the formula La{sub 0.6}Sr{sub 0.4}Co{sub y}Fe{sub 1-y}O{sub 3-{delta}} for y = 0.1, 0.2, and 0.3 have been investigated. The properties were found to strongly depend upon Co content, temperature, and environment. The materials were selected due to their potential use as solid oxide fuel cell cathodes. The intermediate Co loading formed oxygen vacancies most easily and several other properties including oxidation activity and surface sites showed a similar non-linear trend. Trends are related to a possible transition in electronic structure. Activity for oxidation of methane, oxygen storage and chemical compatibility was shown to be superior to that of the La{sub 0.6}Sr{sub 0.4}MnO{sub 3}.

  16. Mobilization of the active MITE transposons mPing and Pong in rice by introgression from wild rice (Zizania latifolia Griseb.).

    PubMed

    Shan, Xiaohui; Liu, Zhenlan; Dong, Zhenying; Wang, Yongming; Chen, Yu; Lin, Xiuyun; Long, Likun; Han, Fangpu; Dong, Yingshan; Liu, Bao

    2005-04-01

    Hybridization between different species plays an important role in plant genome evolution, as well as is a widely used approach for crop improvement. McClintock has predicted that plant wide hybridization constitutes a "genomic shock" whereby cryptic transposable elements may be activated. However, direct experimental evidence showing a causal relationship between plant wide hybridization and transposon mobilization has not yet been reported. The miniature-Ping (mPing) is a recently isolated active miniature inverted-repeat transposable element transposon from rice, which is mobilized by tissue culture and gamma-ray irradiation. We show herein that mPing, together with its putative transposase-encoding partner, Pong, is mobilized in three homologous recombinant inbred lines (RILs), derived from hybridization between rice (cultivar Matsumae) and wild rice (Zizania latifolia Griseb.), harboring introgressed genomic DNA from wild rice. In contrast, both elements remain immobile in two lines sharing the same parentage to the RILs but possessing no introgressed DNA. Thus, we have presented direct evidence that is consistent with McClintock's insight by demonstrating a causal link between wide hybridization and transposon mobilization in rice. In addition, we report an atypical behavior of mPing/Pong mobilization in these lines, i.e., the exclusive absence of footprints after excision. PMID:15647520

  17. Conceptualization and measurement of environmental exposure in epidemiology: accounting for activity space related to daily mobility.

    PubMed

    Perchoux, Camille; Chaix, Basile; Cummins, Steven; Kestens, Yan

    2013-05-01

    A considerable body of literature has investigated how environmental exposures affect health through various pathways. These studies have generally adopted a common approach to define environmental exposures, focusing on the local residential environment, using census tracts or postcodes to delimit exposures. However, use of such administrative units may not be appropriate to evaluate contextual effets on health because they are generally not a 'true' representation of the environments to which individuals are exposed. Recent work has suggested that advances may be made if an activity-space approach is adopted. The present paper investigates how various disciplines may contribute to the refinement of the concept of activity space for use in health research. In particular we draw on seminal work in time geography, which provides a framework to describe individual behavior in space and time, and can help the conceptualization of activity space. In addition we review work in environmental psychology and social networks research, which provides insights on how people and places interact and offers new theories for improving the spatial definition of contextual exposures.

  18. Inertial measurements of free-living activities: assessing mobility to predict falls.

    PubMed

    Wang, Kejia; Lovell, Nigel H; Del Rosario, Michael B; Liu, Ying; Wang, Jingjing; Narayanan, Michael R; Brodie, Matthew A D; Delbaere, Kim; Menant, Jasmine; Lord, Stephen R; Redmond, Stephen J

    2014-01-01

    An exploratory analysis was conducted into how simple features, from acceleration at the lower back and ankle during simulated free-living walking, stair ascent and descent, correlate with age, the overall fall risk from a clinically validated Physiological Profile Assessment (PPA), and its sub-components. Inertial data were captured from 92 older adults aged 78-95 (42 female, mean age 84.1, standard deviation 3.9 years). The dominant frequency, peak width from Welch's power spectral density estimate, and signal variance along each axis, from each sensor location and for each activity were calculated. Several correlations were found between these features and the physiological risk factors. The strongest correlations were from the dominant frequency at the ankle along the mediolateral direction during stair ascent (Spearman's correlation coefficient p = - 0.45) with anterioposterior sway, and signal variance of the anterioposterior acceleration at the lower back during stair descent (p = - 0.45) with age. These findings should aid future attempts to classify activities and predict falls in older adults, based on true free-living data from a range of activities.

  19. Mobile Apps for Librarians

    ERIC Educational Resources Information Center

    Power, June L.

    2013-01-01

    In an increasing mobile environment, library and reading-related activities often take place on a phone or tablet device. Not only does this mean that library Web sites must keep mobile navigability in mind, but also develop and utilize apps that allow patrons to interact with information and with libraries. While apps do not serve every purpose,…

  20. Local context influence, activity space, and foodscape exposure in two canadian metropolitan settings: is daily mobility exposure associated with overweight?

    PubMed

    Lebel, Alexandre; Kestens, Yan; Pampalon, Robert; Thériault, Marius; Daniel, Mark; Subramanian, S V

    2012-01-01

    It has become increasingly common to attribute part of the obesity epidemic to changes in the environment. Identification of a clear and obvious role for contextual risk factors has not yet been demonstrated. The objectives of this study were to explain differences in local overweight risk in two different urban settings and to explore sex-specific associations with estimated mobility patterns. Overweight was modeled within a multilevel framework using built environmental and socioeconomic contextual indicators and individual-level estimates of activity space exposure to fast-food restaurants (or exposure to visited places). Significant variations in local levels in overweight risk were observed. Physical and socioeconomic contexts explained more area-level differences in overweight among men than among women and among inhabitants of Montreal than among inhabitants of Quebec City. Estimated activity space exposure to fast-food outlets was significantly associated with overweight for men in Montreal. Local-level analyses are required to improve our understanding of contextual influences on obesity, including multiple influences in people's daily geographies.

  1. Measurement and Intervention on Physical Activity and Sedentary Behaviours in Bariatric Surgery Patients: Emphasis on Mobile Technology.

    PubMed

    Bond, Dale S; Thomas, J Graham

    2015-11-01

    Physical activity (PA) and sedentary behaviours (SB-i.e. activities involving low-energy expenditure and a sitting/reclining posture) may each have significant implications for weight loss and other bariatric surgery outcomes. While early studies suggested that patients typically comply with clinical recommendations to adopt habitual PA, these data were based on retrospective questionnaires. Conversely, recent studies incorporating mobile health (mHealth) technologies (e.g. objective monitors), which assess PA and SB in real time and in the natural environment, show that most patients are inactive and highly sedentary pre-operatively and only make modest changes in these behaviours postoperatively. In addition to using mHealth technologies for obtaining accurate and detailed information on PA and SB, they are increasingly being employed to intervene on patients' PA and SB and/or evaluate intervention outcomes. Researchers and clinicians are encouraged to consider the benefits of using mHealth technology when studying and treating PA and SB in bariatric surgery patients.

  2. The high mobility group box 1 protein of Sciaenops ocellatus is a secreted cytokine that stimulates macrophage activation.

    PubMed

    Zhao, Lu; Hu, Yong-Hua; Sun, Jin-Sheng; Sun, Li

    2011-10-01

    High mobility group box 1 protein (HMGB1) is a chromatin-associated nonhistone protein that is involved in nucleosome formation and transcriptional regulation. In addition, HMGB1 is also known as an extracellular cytokine that triggers inflammation and immune responses. HMGB1-like sequences have been identified in a number of fish species, however, the function of piscine HMGB1 remains uninvestigated. In this study, we reported the identification and analysis of SoHMGB1, an HMGB1 homologue from red drum (Sciaenops ocellatus). SoHMGB1 is 206 residues in length and contains two basic HMG boxes and a highly acidic C-terminal domain. SoHMGB1 shares 71-87% overall sequence identities with the HMGB1 counterparts from human, rat, and several fish species. Quantitative real time RT-PCR analysis showed that constitutive SoHMGB1 expression was detected in various tissues, with the lowest and highest levels found in kidney and muscle respectively. Bacterial challenge upregulated SoHMGB1 expression in head kidney (HK) and HK macrophages and induced extracellular secretion of SoHMGB1 by the activated macrophages. Recombinant SoHMGB1 (rSoHMGB1) purified from yeast exhibited no direct antimicrobial effect but was significantly stimulatory on the proliferation, activation, and bactericidal activity of HK macrophages. Taken together, these results indicate for the first time that a fish HMGB1, SoHMGB1, can function as a secreted cytokine in the event of bacterial infection and promote innate defense through the activation of macrophages. PMID:21527276

  3. Dendritic Slow Dynamics Enables Localized Cortical Activity to Switch between Mobile and Immobile Modes with Noisy Background Input

    PubMed Central

    Kurashige, Hiroki; Câteau, Hideyuki

    2011-01-01

    Mounting lines of evidence suggest the significant computational ability of a single neuron empowered by active dendritic dynamics. This motivates us to study what functionality can be acquired by a network of such neurons. The present paper studies how such rich single-neuron dendritic dynamics affects the network dynamics, a question which has scarcely been specifically studied to date. We simulate neurons with active dendrites networked locally like cortical pyramidal neurons, and find that naturally arising localized activity – called a bump – can be in two distinct modes, mobile or immobile. The mode can be switched back and forth by transient input to the cortical network. Interestingly, this functionality arises only if each neuron is equipped with the observed slow dendritic dynamics and with in vivo-like noisy background input. If the bump activity is considered to indicate a point of attention in the sensory areas or to indicate a representation of memory in the storage areas of the cortex, this would imply that the flexible mode switching would be of great potential use for the brain as an information processing device. We derive these conclusions using a natural extension of the conventional field model, which is defined by combining two distinct fields, one representing the somatic population and the other representing the dendritic population. With this tool, we analyze the spatial distribution of the degree of after-spike adaptation and explain how we can understand the presence of the two distinct modes and switching between the modes. We also discuss the possible functional impact of this mode-switching ability. PMID:21931635

  4. An Augmented Reality-Based Mobile Learning System to Improve Students' Learning Achievements and Motivations in Natural Science Inquiry Activities

    ERIC Educational Resources Information Center

    Chiang, Tosti H. C.; Yang, Stephen J. H.; Hwang, Gwo-Jen

    2014-01-01

    In this study, an augmented reality-based mobile learning system is proposed for conducting inquiry-based learning activities. An experiment has been conducted to examine the effectiveness of the proposed approach in terms of learning achievements and motivations. The subjects were 57 fourth graders from two classes taught by the same teacher in…

  5. Evaluation of the maximum permissible level of low-intensity electromagnetic radiation at mobile connection frequency (1 GHz) by changes in motor activity of Spirostomum Ambiguum.

    PubMed

    Sarapultseva, E I; Igolkina, J V; Litovchenko, A V

    2009-04-01

    Electromagnetic radiation at the mobile connection frequency (1 GHz) at maximum energy flow density (10 microW/cm(2)) permitted in Russia causes serious functional disorders in the studied unicellular hydrobionts infusoria Spirostomum ambiguum: reduction of their spontaneous motor activity. The form of biological reaction is uncommon: the effect is threshold, overall, and does not depend on the duration of microwave exposure.

  6. Antihypertensive use and the effect of a physical activity intervention in the prevention of major mobility disability among older adults: The LIFE study

    Technology Transfer Automated Retrieval System (TEKTRAN)

    BACKGROUND: This subgroup analysis of the Lifestyle Intervention and Independence for Elders trial evaluates the impact of a long-term physical activity (PA) intervention on rates of major mobility disability (MMD) among older adults according to their antihypertensive medication use. METHODS: Lifes...

  7. The molecular basis of Rieger syndrome. Analysis of Pitx2 homeodomain protein activities.

    PubMed

    Amendt, B A; Sutherland, L B; Semina, E V; Russo, A F

    1998-08-01

    Rieger syndrome is an autosomal-dominant developmental disorder that includes glaucoma and mild craniofacial dysmorphism in humans. Mutations in the Pitx2 homeobox gene have been linked to Rieger syndrome. We have characterized wild type and mutant Pitx2 activities using electrophoretic mobility shift assays, protein binding, and transient transfection assays. Pitx2 preferentially binds the bicoid homeodomain binding site and transactivates reporter genes containing this site. The combination of Pitx2 and another homeodomain protein, Pit-1, yielded a synergistic 55-fold activation of the prolactin promoter in transfection assays. Addition of Pit-1 increased Pitx2 binding to the bicoid element in electrophoretic mobility shift assays. Furthermore, we demonstrate specific binding of Pit-1 to Pitx2 in vitro. Thus, wild type Pitx2 DNA binding activity is modulated by protein-protein interactions. We next studied two Rieger mutants. A threonine to proline mutation (T68P) in the second helix of the homeodomain retained DNA binding activity with the same apparent KD and only about a 2-fold reduction in the Bmax. However, this mutant did not transactivate reporter genes containing the bicoid site. The mutant Pitx2 protein binds Pit-1, but there was no detectable synergism on the prolactin promoter. A second mutation (L54Q) in a highly conserved residue in helix 1 of the homeodomain yielded an unstable protein. Our results provide insights into the potential mechanisms underlying the developmental defects in Rieger syndrome. PMID:9685346

  8. Assessment of highly active dune mobility in the medium, short and very short term

    NASA Astrophysics Data System (ADS)

    Navarro, Marina; Muñoz-Pérez, Juan J.; Román-Sierra, Jorge; Tsoar, Haim; Rodríguez, Inmaculada; Gómez-Pina, Gregorio

    2011-06-01

    Dune activity or stability has usually been studied over long time periods; however, this may not reflect changes that occur in the short term, especially for highly active dunefields. Extreme wind conditions that are generated near the Strait of Gibraltar (SW Spain) have given rise to the transgressive Valdevaqueros dunefield. The current work focuses on analyzing the sand drift potential and the evolution of the dune profile in the medium term (months), the short term (days) and the very short term (hours). Topographic data, which were collected with a differential GPS, were interpreted from reconstructed empirical orthogonal functions (EOF). The results showed that generally the dune profile presented shifting morphologies, especially around the crest and brink, and a trend towards migration to a gentler steady state. As a result, the leeward side adopted continuous slope variations during the different survey periods, whereas the windward slope did not undergo any significant change. Lateral and vertical displacements were analyzed during a severe easterly sandstorm, when the dune brink experienced an advance migration rate of 1.75 m in 24 h. Sand transport rates of 25.5-36.5 m 3 m - 1 month - 1 , 22.52 m 3 m - 1 day - 1 and 0.93 m 3 m - 1 h - 1 were measured for the medium term, short term and very short term, respectively. These values were compared to the theoretical sand transport rate for Valdevaqueros dune, based on the classic Bagnold equation as well other more recent formulae, to obtain a ratio between the real and the theoretical rates for each study period. These results together with the sand drift potential (up to 10,000 vector units) demonstrate that Valdevaqueros (Tarifa) is a dunefield with one of the highest sand transport capacities in Europe.

  9. Escape from Lethal Bacterial Competition through Coupled Activation of Antibiotic Resistance and a Mobilized Subpopulation

    PubMed Central

    Stubbendieck, Reed M.; Straight, Paul D.

    2015-01-01

    Bacteria have diverse mechanisms for competition that include biosynthesis of extracellular enzymes and antibiotic metabolites, as well as changes in community physiology, such as biofilm formation or motility. Considered collectively, networks of competitive functions for any organism determine success or failure in competition. How bacteria integrate different mechanisms to optimize competitive fitness is not well studied. Here we study a model competitive interaction between two soil bacteria: Bacillus subtilis and Streptomyces sp. Mg1 (S. Mg1). On an agar surface, colonies of B. subtilis suffer cellular lysis and progressive degradation caused by S. Mg1 cultured at a distance. We identify the lytic and degradative activity (LDA) as linearmycins, which are produced by S. Mg1 and are sufficient to cause lysis of B. subtilis. We obtained B. subtilis mutants spontaneously resistant to LDA (LDAR) that have visibly distinctive morphology and spread across the agar surface. Every LDAR mutant identified had a missense mutation in yfiJK, which encodes a previously uncharacterized two-component signaling system. We confirmed that gain-of-function alleles in yfiJK cause a combination of LDAR, changes in colony morphology, and motility. Downstream of yfiJK are the yfiLMN genes, which encode an ATP-binding cassette transporter. We show that yfiLMN genes are necessary for LDA resistance. The developmental phenotypes of LDAR mutants are genetically separable from LDA resistance, suggesting that the two competitive functions are distinct, but regulated by a single two-component system. Our findings suggest that a subpopulation of B. subtilis activate an array of defensive responses to counter lytic stress imposed by competition. Coordinated regulation of development and antibiotic resistance is a streamlined mechanism to promote competitive fitness of bacteria. PMID:26647299

  10. Using Mobile Devices in Physical Education to Enhance Learning and Physical Activity for At-Risk Girls

    ERIC Educational Resources Information Center

    Gibbone, Anne; Perez, Samantha L.; Virgilio, Stephen J.

    2014-01-01

    The purpose of the article is to illustrate how a physical education program uses mobile devices to motivate at-risk girls attending an urban charter school. Permitting students to use mobile devices in physical education gives students a "technological freedom" that has been removed in other contexts. The apps described in this article…

  11. Activity Theory Approach to Developing Context-Aware Mobile Learning Systems for Understanding Scientific Phenomenon and Theories

    ERIC Educational Resources Information Center

    Uden, Lorna; Hwang, Gwo-Jen

    2013-01-01

    Mobile computing offers potential opportunities for students' learning especially when it combines a sensing device such as RFID (Radio Frequency Identification). Researchers have indicated that a key feature of in-field learning supported by mobile devices and technology is context awareness, with which context and functionality provided by…

  12. Fenton fragmentation for faster electrophoretic on chip purification of amplifiable genomic DNA.

    PubMed

    Hakenberg, S; Hügle, M; Meyer, P; Behrmann, O; Dame, G; Urban, G A

    2015-05-15

    With a rapid and simple actuation protocol electrophoretic nucleic acid extraction is easy automatable, requires no moving parts, is easy to miniaturize and furthermore possesses a size dependent cut-off filter adjustable by the pore size of the hydrogel. However electrophoretic nucleic acid extraction from bacteria has so far been applied mainly for short RNA targets. One of the reasons is that electrophoretic processing of unfragmented genomic DNA strands is time-consuming, because of the length. Here DNA fragmentation would accelerate extraction and isolation. We introduce on-chip lysis and non-enzymatic DNA cleavage directly followed by a purifying step for receiving amplifiable DNA fragments from bacteria in less than 25 min. In contrast to restriction enzymes the Fenton reaction is known to cleave DNA without nucleotide specificity. The reaction mix contains iron(II) EDTA, sodium ascorbate, hydrogen peroxide and lysozyme. The degree of fragmentation can be adjusted by the concentration of reagents. The results enable electrophoretic extraction methods to unspecifically process long genomic DNA in a short time frame, e.g. for pathogen detection in a lab-on-a-chip format.

  13. Fenton fragmentation for faster electrophoretic on chip purification of amplifiable genomic DNA.

    PubMed

    Hakenberg, S; Hügle, M; Meyer, P; Behrmann, O; Dame, G; Urban, G A

    2015-05-15

    With a rapid and simple actuation protocol electrophoretic nucleic acid extraction is easy automatable, requires no moving parts, is easy to miniaturize and furthermore possesses a size dependent cut-off filter adjustable by the pore size of the hydrogel. However electrophoretic nucleic acid extraction from bacteria has so far been applied mainly for short RNA targets. One of the reasons is that electrophoretic processing of unfragmented genomic DNA strands is time-consuming, because of the length. Here DNA fragmentation would accelerate extraction and isolation. We introduce on-chip lysis and non-enzymatic DNA cleavage directly followed by a purifying step for receiving amplifiable DNA fragments from bacteria in less than 25 min. In contrast to restriction enzymes the Fenton reaction is known to cleave DNA without nucleotide specificity. The reaction mix contains iron(II) EDTA, sodium ascorbate, hydrogen peroxide and lysozyme. The degree of fragmentation can be adjusted by the concentration of reagents. The results enable electrophoretic extraction methods to unspecifically process long genomic DNA in a short time frame, e.g. for pathogen detection in a lab-on-a-chip format. PMID:24970713

  14. Electrophoretic isoenzyme patterns of the pathogenic and non-pathogenic intestinal amoebae of man.

    PubMed

    Sargeaunt, P G; Williams, J E

    1979-01-01

    Cultured stocks of Entamoeba hartmanni, Endolimax nana, Iodamoeba buetschlli and Dientamoeba fragilis were compared with the four Entamoeba histolytical groups already described (SARGEAUNT et al., 1978), by the electrophoretic patterns of three enzymes: glucose phosphate isomerase (GPI), phosphoglucomutase (PGM) and L-malate: NADP+ oxidoreductase (oxalacetate-decarboxylating) (ME). All the species were easily distinguished by their characteristic patterns. PMID:473310

  15. Electrophoretic Deposition for Cholesteric Liquid-Crystalline Devices with Memory and Modulation of Reflection Colors.

    PubMed

    Tokunaga, Shoichi; Itoh, Yoshimitsu; Yaguchi, Yuya; Tanaka, Hiroyuki; Araoka, Fumito; Takezoe, Hideo; Aida, Takuzo

    2016-06-01

    The first design strategy that allows both memorization and modulation of the liquid-crystalline reflection color is reported. Electrophoretic deposition of a tailored ionic chiral dopant is key to realizing this unprecedented function, which may pave the way for the development of full-color e-paper that can operate without the need of color filters. PMID:27027423

  16. Electrophoretic purification of radioiodinated follicle-stimulating hormone for radioligand receptor assay and radioimmunoassay

    SciTech Connect

    Schneyer, A.L.; Sluss, P.M.; Bosukonda, D.; Reichert, L.E. Jr.

    1986-10-01

    A method is described for electrophoretic purification of (/sup 125/I)human (h) FSH after radioiodination that improves radioligand binding to FSH membrane receptors. Lactoperoxidase-iodinated hFSH was separated from reaction products by electrophoresis on 7.5% polyacrylamide tube gels (PAGE). Material eluted from 3-mm gel slices was analyzed for incorporation of /sup 125/I and binding to antibody (RIA) or receptor (RRA), and by sodium dodecyl sulfate-PAGE for protein composition. Sodium dodecyl sulfate-PAGE analysis of individual PAGE fractions demonstrated that iodinated proteins, both higher and lower in apparent mol wt than intact FSH, were separated by PAGE, but not by gel filtration chromatography (Sephadex G-25). PAGE purification of radioligand resulted in significantly greater (compared to gel filtration) RRA sensitivity and specificity. Maximum binding of PAGE-purified (/sup 125/I)hFSH to excess calf tests membrane receptors was 45%, with a specific activity of approximately 26 microCi/micrograms, as determined by the method of self-displacement. Maximum binding to excess hFSH antisera (NIH anti-hFSH 4) was 80-85%. This allowed a useful final dilution of 1:120,000, thereby facilitating development of a sensitive and specific RIA with this antiserum. These data indicate that PAGE separation of intact (/sup 125/I)hFSH from other iodinated proteins results in improved radioligand binding, assay sensitivity, and assay specificity. In addition, PAGE-purified lactoperoxidase-iodinated hFSH is suitable for use in both RIA and RRA.

  17. An aeronautical mobile satellite experiment

    NASA Technical Reports Server (NTRS)

    Jedrey, T. C.; Dessouky, K. I.; Lay, N. E.

    1990-01-01

    The various activities and findings of a NASA/FAA/COMSAT/INMARSAT collaborative aeronautical mobile satellite experiment are detailed. The primary objective of the experiment was to demonstrate and evaluate an advanced digital mobile satellite terminal developed at the Jet Propulsion Laboratory under the NASA Mobile Satellite Program. The experiment was a significant milestone for NASA/JPL, since it was the first test of the mobile terminal in a true mobile satellite environment. The results were also of interest to the general mobile satellite community because of the advanced nature of the technologies employed in the terminal.

  18. Mobile Transporter

    NASA Technical Reports Server (NTRS)

    2001-01-01

    The Space Shuttle Atlantis, STS-110 mission, deployed this railcar, called the Mobile Transporter, and an initial 43-foot section of track, the S0 (S-zero) truss, preparing the International Space Station (ISS) for future spacewalks. The first railroad in space, the Mobile Transporter will allow the Station's robotic arm to travel up and down the finished truss for future assembly and maintenance. The 27,000-pound S0 truss is the first of 9 segments that will make up the Station's external framework that will eventually stretch 356 feet (109 meters), or approximately the length of a football field. The completed truss structure will hold solar arrays and radiators to provide power and cooling for additional international research laboratories from Japan and Europe that will be attached to the Station. The Space Shuttle Orbiter Atlantis, STS-110 mission, was launched April 8, 2002 and returned to Earth April 19, 2002. STS-110's Extravehicular Activity (EVA) marked the first use of the Station's robotic arm to maneuver spacewalkers around the Station.

  19. Mobility of Source Zone Heavy Metals and Radionuclides: The Mixed Roles of Fermentative Activity on Fate and Transport of U and Cr

    SciTech Connect

    Apel, William; Peyton, Brent; Gerlach, Robin; Lee, Brady

    2006-04-05

    Various U. S. Department of Energy (DOE) low and medium-level radioactive waste sites contain mixtures of heavy metals, radionuclides and assorted organic materials. Over time, water infiltrates the wastes, and releases metals and radionuclides causing transport into the surrounding environment. We propose that fermentative microorganisms are active in these sites and may control metal and radionuclide migration from source zones (Figure 1). The following overarching hypothesis will drive our research: 'Metals and radionuclides can be mobilized by infiltration of water into waste storage sites. Microbial communities of lignocellulose degrading and fermenting microorganisms present in the subsurface of contaminated DOE sites can significantly impact migration by directly reducing and immobilizing metals and radionuclides while degrading complex organic matter to low molecular weight organic compounds. These low molecular weight organic compounds can increase metal and radionuclide mobility by chelation (i.e., certain organic acids) or decrease mobility by stimulating respiratory metal reducing microorganisms.' The objective of our research is to determine the effect of carbon and energy flow through simulated waste environments on metal and radionuclide migration from waste pits and trenches across the DOE complex. Metals and radionuclides can be mobilized by infiltration of water into waste storage sites. Cellulolytic and non-cellulolytic fermentative microorganisms have been chosen as the focus of this research because their activity is a critical first step that we hypothesize will control subsequent fate and transport in contaminated natural systems. Microbial communities of lignocellulose degrading and fermenting microorganisms present in the subsurface of contaminated DOE sites can significantly impact migration by directly reducing and immobilizing metals and radionuclides while degrading complex organic matter to low molecular weight organic compounds. These

  20. Late Holocene dune mobilizations in the northwestern Negev dunefield, Israel: A response to combined anthropogenic activity and short-term intensified windiness

    NASA Astrophysics Data System (ADS)

    Roskin, Joel; Katra, Itzhak; Blumberg, Dan G.

    2013-04-01

    The study of the effects of past climates on ancient cultures is usually based on geologic records pertaining to rainfall and temperature fluctuations and shifts. This study proposes a paradigm of anthropogenic activity and windiness fluctuations to explain aeolian sedimentation and dune mobilization in the northwestern (NW) Negev Desert dunefield (Israel). The proposed paradigm contributes a different approach to estimating the effect of climate changes on the unprecedented agricultural and urban settlement expansion during the late Roman to Early Islamic period in the northern and central Negev Desert. This study builds upon the late Holocene cluster of luminescence ages of Roskin et al. (Age, origin and climatic controls on vegetated linear dunes in the northwestern Negev Desert (Israel), Quaternary Science Reviews 30 (2011), 1649-1674) coupled with analysis of archaeological finds and historical texts. We suggest that whereas the NW Negev dunefield was generally stable during the Holocene, intermittent dune mobilization during the late Holocene, at ~1.8 ka and mostly 1.4-1.1 ka (~600-900 CE), are linked to periods of human occupation. The idea that the last glacial dune encroachments alone that formed the NW Negev dunefield is connected to cold-event windy climates that may have intensified East Mediterranean cyclonic winter storms, cannot explain the late Holocene dune mobilizations. We conceptually model a connection between late Holocene dune mobilization, widespread anthropogenic occupation and activity, and windiness. We maintain that historic grazing and uprooting shrubs for fuel in the past by nomads and sedentary populations led to decimation of dune stabilizers, biogenic soil crusts and vegetation, causing dune erodibility and low-grade activity. Short-term events of amplified wind power in conjunction with periods of augmented anthropogenic activity that triggered major events of dune mobilization (elongation) and accretion have been preserved in the

  1. Designing a Culturally Appropriate Visually Enhanced Low-Text Mobile Health App Promoting Physical Activity for Latinos: A Qualitative Study.

    PubMed

    Bender, Melinda S; Martinez, Suzanna; Kennedy, Christine

    2016-07-01

    Rapid proliferation of smartphone ownership and use among Latinos offers a unique opportunity to employ innovative visually enhanced low-text (VELT) mobile health applications (mHealth app) to promote health behavior change for Latinos at risk for lifestyle-related diseases. Using focus groups and in-depth interviews with 16 promotores and 5 health care providers recruited from California clinics, this qualitative study explored perceptions of visuals for a VELT mHealth app promoting physical activity (PA) and limiting sedentary behavior (SB) for Latinos. In this Phase 1 study, participants endorsed visuals portraying PA guidelines and recommended visuals depicting family and socially oriented PA. Overall, participants supported a VELT mHealth app as an alternative to text-based education. Findings will inform the future Phase 2 study development of a culturally appropriate VELT mHealth app to promote PA for Latinos, improve health literacy, and provide an alternative to traditional clinic text-based health education materials.

  2. Tests of an alternate mobile transporter and extravehicular activity assembly procedure for the Space Station Freedom truss

    NASA Technical Reports Server (NTRS)

    Heard, Walter L., Jr.; Watson, Judith J.; Lake, Mark S.; Bush, Harold G.; Jensen, J. Kermit; Wallsom, Richard E.; Phelps, James E.

    1992-01-01

    Results are presented from a ground test program of an alternate mobile transporter (MT) concept and extravehicular activity (EVA) assembly procedure for the Space Station Freedom (SSF) truss keel. A three-bay orthogonal tetrahedral truss beam consisting of 44 2-in-diameter struts and 16 nodes was assembled repeatedly in neutral buoyancy by pairs of pressure-suited test subjects working from astronaut positioning devices (APD's) on the MT. The truss bays were cubic with edges 15 ft long. All the truss joint hardware was found to be EVA compatible. The average unit assembly time for a single pair of experienced test subjects was 27.6 sec/strut, which is about half the time derived from other SSF truss assembly tests. A concept for integration of utility trays during truss assembly is introduced and demonstrated in the assembly tests. The concept, which requires minimal EVA handling of the trays, is shown to have little impact on overall assembly time. The results of these tests indicate that by using an MT equipped with APD's, rapid EVA assembly of a space station-size truss structure can be expected.

  3. Mobilization of Copper ions by Flavonoids in Human Peripheral Lymphocytes Leads to Oxidative DNA Breakage: A Structure Activity Study.

    PubMed

    Arif, Hussain; Rehmani, Nida; Farhan, Mohd; Ahmad, Aamir; Hadi, Sheikh Mumtaz

    2015-11-09

    Epidemiological studies have linked dietary consumption of plant polyphenols with lower incidence of various cancers. In particular, flavonoids (present in onion, tomato and other plant sources) induce apoptosis and cytotoxicity in cancer cells. These can therefore be used as lead compounds for the synthesis of novel anticancer drugs with greater bioavailability. In the present study, we examined the chemical basis of cytotoxicity of flavonoids by studying the structure-activity relationship of myricetin (MN), fisetin (FN), quercetin (QN), kaempferol (KL) and galangin (GN). Using single cell alkaline gel electrophoresis (comet assay), we established the relative efficiency of cellular DNA breakage as MN > FN > QN > KL > GN. Also, we determined that the cellular DNA breakage was the result of mobilization of chromatin-bound copper ions and the generation of reactive oxygen species. The relative DNA binding affinity order was further confirmed using molecular docking and thermodynamic studies through the interaction of flavonoids with calf thymus DNA. Our results suggest that novel anti-cancer molecules should have ortho-dihydroxy groups in B-ring and hydroxyl groups at positions 3 and 5 in the A-ring system. Additional hydroxyl groups at other positions further enhance the cellular cytotoxicity of the flavonoids.

  4. Mobilization of copper ions in human peripheral lymphocytes by catechins leading to oxidative DNA breakage: A structure activity study.

    PubMed

    Farhan, Mohd; Zafar, Atif; Chibber, Sandesh; Khan, Husain Yar; Arif, Hussain; Hadi, S M

    2015-08-15

    Epidemiological studies suggest that dietary consumption of plant polyphenols is related to a lower incidence of various cancers. Among these compounds catechins (present in green tea and other beverages) are considered to be potent inducers of apoptosis and cytotoxicity to cancer cells. Thus these compounds can be used as leads to synthesize novel anticancer drugs with greater bioavailability. In view of this in this paper we have examined the chemical basis of cytotoxicity of catechins by studying the structure-activity relationship between catechin (C), epicatechin (EC), epigallocatechin (EGC) and epigallocatechin-3-gallate (EGCG). Using single cell alkaline gel electrophoresis (comet assay) we have established the relative efficiency of cellular DNA breakage as EGCG>EGC>EC>C. We also show that cellular DNA breakage is the result of mobilization of copper ions bound to chromatin and the generation of reactive oxygen species. Further the relative DNA binding affinity order was confirmed using molecular docking and thermodynamic studies by studying the interaction of catechins with calf thymus DNA. The results suggest that the synthesis of any novel anti cancer molecule based on the structure of catechins should have as many galloyl moieties as possible resulting in an increased number of hydroxyl groups that may facilitate the binding of the molecule to cellular DNA.

  5. Mobilization of Copper ions by Flavonoids in Human Peripheral Lymphocytes Leads to Oxidative DNA Breakage: A Structure Activity Study

    PubMed Central

    Arif, Hussain; Rehmani, Nida; Farhan, Mohd; Ahmad, Aamir; Hadi, Sheikh Mumtaz

    2015-01-01

    Epidemiological studies have linked dietary consumption of plant polyphenols with lower incidence of various cancers. In particular, flavonoids (present in onion, tomato and other plant sources) induce apoptosis and cytotoxicity in cancer cells. These can therefore be used as lead compounds for the synthesis of novel anticancer drugs with greater bioavailability. In the present study, we examined the chemical basis of cytotoxicity of flavonoids by studying the structure–activity relationship of myricetin (MN), fisetin (FN), quercetin (QN), kaempferol (KL) and galangin (GN). Using single cell alkaline gel electrophoresis (comet assay), we established the relative efficiency of cellular DNA breakage as MN > FN > QN > KL > GN. Also, we determined that the cellular DNA breakage was the result of mobilization of chromatin-bound copper ions and the generation of reactive oxygen species. The relative DNA binding affinity order was further confirmed using molecular docking and thermodynamic studies through the interaction of flavonoids with calf thymus DNA. Our results suggest that novel anti-cancer molecules should have ortho-dihydroxy groups in B-ring and hydroxyl groups at positions 3 and 5 in the A-ring system. Additional hydroxyl groups at other positions further enhance the cellular cytotoxicity of the flavonoids. PMID:26569217

  6. Differential arsenic mobilization from As-bearing ferrihydrite by iron-respiring Shewanella strains with different arsenic-reducing activities.

    PubMed

    Jiang, Shenghua; Lee, Ji-Hoon; Kim, Donghun; Kanaly, Robert A; Kim, Min-Gyu; Hur, Hor-Gil

    2013-08-01

    Arsenic immobilization and release in the environment is significantly influenced by bacterial oxidation and reduction of arsenic and arsenic-bearing minerals. In this study, we tested three iron-reducing bacteria, Shewanella oneidensis MR-1, Shewanella sp. HN-41, and Shewanella putrefaciens 200, which have diverse arsenate-reducing activities with regard to reduction of an As-bearing ferrihydrite slurry. In the cultures of S. oneidensis MR-1 and Shewanella sp. HN-41, which are not capable of respiratory reduction of As(V) to As(III), arsenic was maintained predominantly in its pentavalent form, existing in particulate poorly crystalline As-bearing ferrihydrite and formed small quantities of a stable ferrous arsenate [Fe3(AsO4)2] precipitate. However, in the culture of the As(V) reducer, S. putrefaciens 200, As(V) was reduced to As(III) and a small fraction of As-bearing ferrihydrite was transformed into ribbon-shaped siderite that subsequently re-released arsenic into the liquid phase. Our results indicated that release of arsenic and formation of diverse secondary nanoscale Fe-As minerals are specifically closely related to the arsenic-reducing abilities of different bacteria. Therefore, bacterial arsenic reduction appears to significantly influence As mobilization in soils, minerals, and other Fe-rich environments.

  7. Mobile apps for pediatric obesity prevention and treatment, healthy eating, and physical activity promotion: just fun and games?

    PubMed

    Schoffman, Danielle E; Turner-McGrievy, Gabrielle; Jones, Sonya J; Wilcox, Sara

    2013-09-01

    Mobile applications (apps) offer a novel way to engage children in behavior change, but little is known about content of commercially available apps for this population. We analyzed the content of apps for iPhone/iPad for pediatric weight loss, healthy eating (HE), and physical activity (PA). Fifty-seven apps were downloaded and tested by two independent raters. Apps were coded for: inclusion of the Expert Committee for Pediatric Obesity Prevention's (ECPOP) eight recommended strategies (e.g., set goals) and seven behavioral targets (e.g., do ≥1 h of PA per day), utilization of gaming elements, and general characteristics. Most apps lacked any expert recommendations (n = 35, 61.4 %). The mean number of recommendations among apps that used recommendations was 3.6 ± 2.7 out of 15, 56.1 % (n = 32) apps were classified as games, and mean price per app was $1.05 ± 1.66. Most apps reviewed lacked expert recommendations and could be strengthened by addition of comprehensive information about health behavior change and opportunities for goal setting. PMID:24073184

  8. Mobilization of Copper ions by Flavonoids in Human Peripheral Lymphocytes Leads to Oxidative DNA Breakage: A Structure Activity Study.

    PubMed

    Arif, Hussain; Rehmani, Nida; Farhan, Mohd; Ahmad, Aamir; Hadi, Sheikh Mumtaz

    2015-01-01

    Epidemiological studies have linked dietary consumption of plant polyphenols with lower incidence of various cancers. In particular, flavonoids (present in onion, tomato and other plant sources) induce apoptosis and cytotoxicity in cancer cells. These can therefore be used as lead compounds for the synthesis of novel anticancer drugs with greater bioavailability. In the present study, we examined the chemical basis of cytotoxicity of flavonoids by studying the structure-activity relationship of myricetin (MN), fisetin (FN), quercetin (QN), kaempferol (KL) and galangin (GN). Using single cell alkaline gel electrophoresis (comet assay), we established the relative efficiency of cellular DNA breakage as MN > FN > QN > KL > GN. Also, we determined that the cellular DNA breakage was the result of mobilization of chromatin-bound copper ions and the generation of reactive oxygen species. The relative DNA binding affinity order was further confirmed using molecular docking and thermodynamic studies through the interaction of flavonoids with calf thymus DNA. Our results suggest that novel anti-cancer molecules should have ortho-dihydroxy groups in B-ring and hydroxyl groups at positions 3 and 5 in the A-ring system. Additional hydroxyl groups at other positions further enhance the cellular cytotoxicity of the flavonoids. PMID:26569217

  9. Immediate effects of the activation of the affected lower limb on the balance and trunk mobility of hemiplegic stroke patients.

    PubMed

    Kim, Young-Dong; Lee, Kyoung-Bo; Roh, Hyo-Lyun

    2015-05-01

    [Purpose] The purpose of this study was to determine the effects of the activation of the affected lower limb on balance and the trunk hemiplegic mobility of stroke patients. [Subjects] The gait group (GG) consisted of 6 subjects with hemiplegia and the non-gait group (NGG) consisted of 6 hemiplegic subjects. [Methods] The subjects in both groups were given foot facilitation training once for 30 min. The Spinal Mouse was used to measure the spinal alignment and the Berg balance scale (BBS) and sensory tests were also performed. [Results] In the GG, the sacral hip in upright to flexion, the lumbar spine in upright to extension, and the sacral hip and lumbar spine in flexion to extension showed significant increases in their angles after the intervention. In addition, there was a significant increase in the angle of the lumbar spine during extension from an upright position in the NGG. The BBS scores of both groups also increased significantly. [Conclusion] The intervention resulted in improvements in the angle of anterior pelvic tilt in the GG, and subjects in the NGG showed more extension of the thorax, which was regarded as compensation to avoid falling forward when flexing from an upright position. However, when extending backward from an upright position, both groups tended to control balance by using more lumbar flexion to keep the center of mass (COM) within the base of support (BOS). Both groups had better BBS scores.

  10. Mobilization of copper ions in human peripheral lymphocytes by catechins leading to oxidative DNA breakage: A structure activity study.

    PubMed

    Farhan, Mohd; Zafar, Atif; Chibber, Sandesh; Khan, Husain Yar; Arif, Hussain; Hadi, S M

    2015-08-15

    Epidemiological studies suggest that dietary consumption of plant polyphenols is related to a lower incidence of various cancers. Among these compounds catechins (present in green tea and other beverages) are considered to be potent inducers of apoptosis and cytotoxicity to cancer cells. Thus these compounds can be used as leads to synthesize novel anticancer drugs with greater bioavailability. In view of this in this paper we have examined the chemical basis of cytotoxicity of catechins by studying the structure-activity relationship between catechin (C), epicatechin (EC), epigallocatechin (EGC) and epigallocatechin-3-gallate (EGCG). Using single cell alkaline gel electrophoresis (comet assay) we have established the relative efficiency of cellular DNA breakage as EGCG>EGC>EC>C. We also show that cellular DNA breakage is the result of mobilization of copper ions bound to chromatin and the generation of reactive oxygen species. Further the relative DNA binding affinity order was confirmed using molecular docking and thermodynamic studies by studying the interaction of catechins with calf thymus DNA. The results suggest that the synthesis of any novel anti cancer molecule based on the structure of catechins should have as many galloyl moieties as possible resulting in an increased number of hydroxyl groups that may facilitate the binding of the molecule to cellular DNA. PMID:26142371

  11. Relation of fatty acid composition in lead-exposed mallards to fat mobilization, lipid peroxidation and alkaline phosphatase activity

    USGS Publications Warehouse

    Mateo, R.; Beyer, W.N.; Spann, J.W.; Hoffman, D.J.

    2003-01-01

    The increase of n-6 polyunsaturated fatty acids (PUFA) in animal tissues has been proposed as a mechanism of Pb poisoning through lipid peroxidation or altered eicosanoids metabolism. We have studied fatty acid (FA) composition in liver and brain of mallards (Anas platyrhynchos) feeding for three weeks on diets containing combinations of low or high levels of vitamin E (20 or 200 UI/kg) and Pb (0 or 2 g/kg). Saturated FA, n-6 PUFA and total concentrations of FA were higher in livers of Pb-exposed mallards, but not in their brains. The percentage of n-6 PUFA in liver and brain was slightly higher in Pb-exposed mallards. The increase of n-6 PUFA in liver was associated with increased triglycerides and cholesterol in plasma, thus could be in part attributed to feed refusal and fat mobilization. The hepatic ratios between adrenic acid (22:4 n-6) and arachidonic acid (20:4 n-6) or between adrenic acid and linoleic acid (18:2 n-6) were higher in Pb exposed birds, supporting the existing hypothesis of increased fatty acid elongation by Pb. Among the possible consequences of increased n-6 PUFA concentration in tissues, we found increased lipid peroxidation in liver without important histopathological changes, and decreased plasma alkaline phosphatase activity that may reflect altered bone metabolism in birds.

  12. Designing a Culturally Appropriate Visually Enhanced Low-Text Mobile Health App Promoting Physical Activity for Latinos: A Qualitative Study.

    PubMed

    Bender, Melinda S; Martinez, Suzanna; Kennedy, Christine

    2016-07-01

    Rapid proliferation of smartphone ownership and use among Latinos offers a unique opportunity to employ innovative visually enhanced low-text (VELT) mobile health applications (mHealth app) to promote health behavior change for Latinos at risk for lifestyle-related diseases. Using focus groups and in-depth interviews with 16 promotores and 5 health care providers recruited from California clinics, this qualitative study explored perceptions of visuals for a VELT mHealth app promoting physical activity (PA) and limiting sedentary behavior (SB) for Latinos. In this Phase 1 study, participants endorsed visuals portraying PA guidelines and recommended visuals depicting family and socially oriented PA. Overall, participants supported a VELT mHealth app as an alternative to text-based education. Findings will inform the future Phase 2 study development of a culturally appropriate VELT mHealth app to promote PA for Latinos, improve health literacy, and provide an alternative to traditional clinic text-based health education materials. PMID:25556208

  13. Electrophoretic Particle Guidance Significantly Enhances Olfactory Drug Delivery: A Feasibility Study

    PubMed Central

    Xi, Jinxiang; Si, Xiuhua A.; Gaide, Rachel

    2014-01-01

    Background Intranasal olfactory drug delivery provides a non-invasive method that bypasses the Blood-Brain-Barrier and directly delivers medication to the brain and spinal cord. However, a device designed specifically for olfactory delivery has not yet been found. Methods In this study, a new delivery method was proposed that utilized electrophoretic forces to guide drug particles to the olfactory region. The feasibility of this method was numerically evaluated in both idealized 2-D and anatomically accurate 3-D nose models. The influence of nasal airflow, electrode strength, and drug release position were also studied on the olfactory delivery efficiency. Findings Results showed that by applying electrophoretic forces, the dosage to the olfactory region was significantly enhanced. In both 2-D and 3-D cases, electrophoretic-guided delivery achieved olfactory dosages nearly two orders of magnitude higher than that without electrophoretic forces. Furthermore, releasing drugs into the upper half of the nostril (i.e., partial release) led to olfactory dosages two times higher than releasing drugs over the entire area of the nostril. By combining the advantages of pointed drug release and appropriate electrophoretic guidance, olfactory dosages of more than 90% were observed as compared to the extremely low olfactory dosage (<1%) with conventional inhaler devices. Conclusion Results of this study have important implications in developing personalized olfactory delivery protocols for the treatment of neurological disorders. Moreover, a high sensitivity of olfactory dosage was observed in relation to different pointed release positions, indicating the importance of precise particle guidance for effective olfactory delivery. PMID:24497957

  14. Mobile learning in medicine

    NASA Astrophysics Data System (ADS)

    Serkan Güllüoüǧlu, Sabri

    2013-03-01

    This paper outlines the main infrastructure for implicating mobile learning in medicine and present a sample mobile learning application for medical learning within the framework of mobile learning systems. Mobile technology is developing nowadays. In this case it will be useful to develop different learning environments using these innovations in internet based distance education. M-learning makes the most of being on location, providing immediate access, being connected, and acknowledges learning that occurs beyond formal learning settings, in places such as the workplace, home, and outdoors. Central to m-learning is the principle that it is the learner who is mobile rather than the device used to deliver m learning. The integration of mobile technologies into training has made learning more accessible and portable. Mobile technologies make it possible for a learner to have access to a computer and subsequently learning material and activities; at any time and in any place. Mobile devices can include: mobile phone, personal digital assistants (PDAs), personal digital media players (eg iPods, MP3 players), portable digital media players, portable digital multimedia players. Mobile learning (m-learning) is particularly important in medical education, and the major users of mobile devices are in the field of medicine. The contexts and environment in which learning occurs necessitates m-learning. Medical students are placed in hospital/clinical settings very early in training and require access to course information and to record and reflect on their experiences while on the move. As a result of this paper, this paper strives to compare and contrast mobile learning with normal learning in medicine from various perspectives and give insights and advises into the essential characteristics of both for sustaining medical education.

  15. High-mobility group box 1 impairs airway epithelial barrier function through the activation of the RAGE/ERK pathway

    PubMed Central

    HUANG, WUFENG; ZHAO, HAIJIN; DONG, HANGMING; WU, YUE; YAO, LIHONG; ZOU, FEI; CAI, SHAOXI

    2016-01-01

    Recent studies have indicated that high-mobility group box 1 protein (HMGB1) and the receptor for advanced glycation end-products (RAGE) contribute to the pathogenesis of asthma. However, whether the activation of the HMGB1/RAGE axis mediates airway epithelial barrier dysfunction remains unknown. Thus, the aim of this study was to examine the effects of HMGB1 and its synergistic action with interleukin (IL)-1β on airway epithelial barrier properties. We evaluated the effects of recombinant human HMGB1 alone or in combination with IL-1β on ionic and macromolecular barrier permeability, by culturing air-liquid interface 16HBE cells with HMGB1 to mimic the differentiated epithelium. Western blot analysis and immunofluorescence staining were utilized to examine the level and structure of major junction proteins, namely E-cadherin, β-catenin, occludin and claudin-1. Furthermore, we examined the effects of RAGE neutralizing antibodies and mitogen-activated protein kinase (MAPK) inhibitors on epithelial barrier properties in order to elucidate the mechanisms involved. HMGB1 increased FITC-dextran permeability, but suppressed epithelial resistance in a dose-and time-dependent manner. HMGB1-mediated barrier hyperpermeability was accompanied by a disruption of cell-cell contacts, the selective downregulation of occludin and claudin-1, and the redistribution of E-cadherin and β-catenin. HMGB1 in synergy with IL-1β induced a similar, but greater barrier hyperpermeability and induced the disruption of junction proteins. Furthermore, HMGB1 elicited the activation of the RAGE/extracellular signal-related kinase (ERK)1/2 signaling pathway, which correlated with barrier dysfunction in the 16HBE cells. Anti-RAGE antibody and the ERK1/2 inhibitor, U0126, attenuated the HMGB1-mediated changes in barrier permeability, restored the expression levels of occludin and claudin-1 and pevented the redistribution of E-cadherin and β-catenin. Taken together, the findings of our study

  16. Mobile neutron/gamma waste assay system for characterization of waste containing transuranics, uranium, and fission/activation products

    SciTech Connect

    Davidson, D.R.; Haggard, D.; Lemons, C.

    1994-12-31

    A new integrated neutron/gamma assay system has been built for measuring 55-gallon drums at Pacific Northwest Laboratory. The system is unique because it allows simultaneous measurement of neutrons and gamma-rays. This technique also allows measurement of transuranics (TRU), uranium, and fission/activation products, screening for shielded Special Nuclear Material prior to disposal, and critically determinations prior to transportation. The new system is positioned on a platform with rollers and installed inside a trailer or large van to allow transportation of the system to the waste site instead of movement of the drums to the scanner. The ability to move the system to the waste drums is particularly useful for drum retrieval programs common to all DOE sites and minimizes transportation problems on the site. For longer campaigns, the system can be moved into a facility. The mobile system consists of two separate subsystems: a passive Segmented Gamma Scanner (SGS) and a {open_quotes}clam-shell{close_quotes} passive neutron counter. The SGS with high purity germanium detector and {sup 75}Se transmission source simultaneously scan the height of the drum allowing identification of unshieled {open_quotes}hot spots{close_quotes} in the drum or segments where the matrix is too dense for the transmission source to penetrate. Dense segments can flag shielding material that could be used to hide plutonium or uranium during the gamma analysis. The passive nuetron counter with JSR-12N Neutron Coincidence Analyzer measures the coincident neutrons from the spontaneous fission of even isotopes of plutonium. Because high-density shielding produces minimal absorption of neutrons, compared to gamma rays, the passive neutron portion of the system can detect shielded SNM. Measurements to evaluate the performance of the system are still underway at Pacific Northwest Laboratory.

  17. Simulation of the potential effects of CO2 leakage from carbon capture and storage activities on the mobilization and speciation of metals.

    PubMed

    de Orte, Manoela Romanó; Sarmiento, Aguasanta M; DelValls, T Ángel; Riba, Inmaculada

    2014-09-15

    One of the main risks associated with carbon capture and storage (CCS) activities is the leakage of the stored CO2, which can result in several effects on the ecosystem. Laboratory-scale experiments were performed to provide data on the possible effects of CO2 leakage from CCS on the mobility of metals previously trapped in sediments. Metal-contaminated sediments were collected and submitted to acidification by means of CO2 injection using different pH treatments. The test lasted 10 days, and samples were collected at the beginning and at the end of the experiment for metal analysis. The results revealed increases in the mobility of metals such as Co, Cu, Fe, Pb and Zn due to pH decreases. Geochemical modeling demonstrated that acidification influenced the speciation of the metals, increasing the concentrations of their free forms. These data suggest the possible sediment contamination consequences of accidental CO2 leakage during CCS activities.

  18. Nanolaminate microfluidic device for mobility selection of particles

    SciTech Connect

    Surh, Michael P.; Wilson, William D.; Barbee, Jr., Troy W.; Lane, Stephen M.

    2006-10-10

    A microfluidic device made from nanolaminate materials that are capable of electrophoretic selection of particles on the basis of their mobility. Nanolaminate materials are generally alternating layers of two materials (one conducting, one insulating) that are made by sputter coating a flat substrate with a large number of layers. Specific subsets of the conducting layers are coupled together to form a single, extended electrode, interleaved with other similar electrodes. Thereby, the subsets of conducting layers may be dynamically charged to create time-dependent potential fields that can trap or transport charge colloidal particles. The addition of time-dependence is applicable to all geometries of nanolaminate electrophoretic and electrochemical designs from sinusoidal to nearly step-like.

  19. Ligand-substitution mode capillary electrophoretic reactor: extending capillary electrophoretic reactor toward measurement of slow dissociation kinetics with a half-life of hours.

    PubMed

    Iki, Nobuhiko; Takahashi, Mariko; Takahashi, Toru; Hoshino, Hitoshi

    2009-09-15

    A method employing capillary electrophoresis (CE) was developed to determine the rate constant of the very slow spontaneous dissociation of a complex species. The method uses a CE reactor (CER) to electrophoretically separate components from a complex zone and, thus, spontaneously dissociate a complex. The dissociation is accelerated by ligand substitution (LS) involving a competing ligand added to the electrophoretic buffer. The LS-CER method is validated using the dissociation of a Ti(IV)-catechin complex and EDTA as a competing ligand. There is good agreement between the spontaneous dissociation rate constant (k(d) = (1.64 +/- 0.63) x 10(-4) s(-1)) and the rate constant obtained by a conventional batchwise LS reaction (k(d) = (1.43 +/- 0.04) x 10(-4) s(-1)). Furthermore, the usefulness of the method is demonstrated using a Ti(IV)-tiron complex, for which k(d) = (0.51 +/- 0.43) x 10(-4) s(-1), corresponding to a half-life (t(1/2)) of 3.8 h. Notably, a single run of LS-CER for the Ti(IV) complex is completed within 40 min, implying that LS-CER requires a considerably shorter measurement time (roughly equal to t(1/2)) than conventional CER. LS-CER can be widely applied to determine the spontaneous dissociation rates of inorganic diagnostic and therapeutic reagents as well as of biomolecular complexes.

  20. Stabilization of green bodies via sacrificial gelling agent during electrophoretic deposition

    DOEpatents

    Worsley, Marcus A.; Kuntz, Joshua D.; Rose, Klint A.

    2016-03-22

    In one embodiment, a method for electrophoretic deposition of a three-dimensionally patterned green body includes suspending a first material in a gelling agent above a patterned electrode of an electrophoretic deposition (EPD) chamber, and gelling the suspension while applying a first electric field to the suspension to cause desired patterning of the first material in a resulting gelation. In another embodiment, a ceramic, metal, or cermet includes a plurality of layers, wherein each layer includes a gradient in composition, microstructure, and/or density in an x-y plane oriented parallel to a plane of deposition of the plurality of layers along a predetermined distance in a z-direction perpendicular to the plane of deposition.