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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 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 ...

  3. 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...

  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 particles in concentrated solutions of electrolytes

    SciTech Connect

    Deinega, Yu.F.; Polyakova, V.M.; Aleksandrova, L.N.

    1986-11-01

    The electrophoretic mobility of particles of phenol-formaldehyde and aniline-formaldehyde resins in zinc sulfate solutions has been investigated. It is shown that as the electrolyte concentration rises, the electrophoretic mobility falls, reaches a minimum, and then increases. A possible mechanism for the formation of an electric double layer on the surface of particles in concentrated solutions of electrolytes is proposed.

  6. 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

  7. Electrophoretic mobilities and migrating analytes: Part 1: Relationships.

    PubMed

    Cross, Reginald F; Wong, Margaret G

    2002-01-01

    The molecular radii (r) of a series of peptides have been determined by molecular modeling. With these data, it is shown that electrophoretic mobility (mu(ep)) is proportional to 1/r2, and that the dependence presented in textbooks (mu(ep) infinity 1/r) is wrong. Use of the approximately equivalent, mass-based Offord equation is discussed, and other relevant considerations are presented. PMID:12546161

  8. 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

  9. 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.

  10. Electrophoretic mobility of spherical particles in bounded domain.

    PubMed

    Liu, Yu-Wei; Pennathur, Sumita; Meinhart, Carl D

    2016-01-01

    In this study, we improve on our 3D steady-state model of electrophoretic motion of spherical particles in bounded fluidic channels (Liu et al., 2014) to include the effect of nonsymmetric electrolytes, and further validate this improved model with detailed comparisons to experimental data. Specifically, we use the experimentally-measured particle mobilities from the work of Semenov et al. (2013), Napoli et al. (2011), and Wynne et al. (2012) to determine the corresponding particle zeta potentials using our model, and compare these results with classical theory. Incorporating the effects of nonsymmetric electrolytes, EDL polarization, and confinement, we show that our improved model is applicable to a wide range of practical experimental conditions, for example, particles that have high zeta potentials in a bounded channel filled with nonsymmetric electrolyte solutions, where classical theory is not applicable. In addition, we find that when electrolyte concentration is comparable to the concentration of hydronium or hydroxide ions, the complicated composition of ions increases the particle mobility. Finally, increased electrophoretic mobility can be observed when buffer solutions (phosphate or borate) were used as electrolyte solutions in experiments as opposed to simple symmetric electrolytes. PMID:26397906

  11. 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

  12. 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.

  13. Electrophoretic mobility patterns of collagen following laser welding

    NASA Astrophysics Data System (ADS)

    Bass, Lawrence S.; Moazami, Nader; Pocsidio, Joanne O.; Oz, Mehmet C.; LoGerfo, Paul; Treat, Michael R.

    1991-06-01

    Clinical application of laser vascular anastomosis in inhibited by a lack of understanding of its mechanism. Whether tissue fusion results from covalent or non-covalent bonding of collagen and other structural proteins is unknown. We compared electrophoretic mobility of collagen in laser treated and untreated specimens of rat tail tendon (>90% type I collagen) and rabbit aorta. Welding was performed, using tissue shrinkage as the clinical endpoint, using the 808 nm diode laser (power density 14 watts/cm2) and topical indocyanine green dye (max absorption 805 nm). Collagen was extracted with 8 M urea (denaturing), 0.5 M acetic acid (non-denaturing) and acetic acid/pepsin (cleaves non- helical protein). Mobility patterns on gel electrophoresis (SDS-PAGE) after urea or acetic acid extraction were identical in the lasered and control tendon and vessel (confirmed by optical densitometry), revealing no evidence of formation of novel covalent bonds. Alpha and beta band intensity was diminished in pepsin incubated lasered specimens compared with controls (optical density ratio 0.00 +/- 9 tendon, 0.65 +/- 0.12 aorta), indicating the presence of denatured collagen. With the laser parameters used, collagen is denatured without formation of covalent bonds, suggesting that non-covalent interaction between denatured collagen molecules may be responsible for the weld. Based on this mechanism, welding parameters can be chosen which produce collagen denaturation without cell death.

  14. 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.

  15. 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.

  16. 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. PMID:24338984

  17. 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

  18. Capillary electrophoresis separation of vinpocetine and related compounds: prediction of electrophoretic mobilities in partly aqueous media.

    PubMed

    Mazák, K; Szakács, Z; Nemes, A; Noszál, B

    2000-07-01

    Offord's equation, a relationship between electrophoretic mobility and charge, size and shape of peptides, has been extended to quantitate the electrophoretic mobility of vinca alkaloids. Partly aqueous protonation constants and the derived theoretical mobilities have been proven to be able to predict experimental electrophoretic mobilities. In practice, seven vincamine derivatives of very low water-solubility were separated by capillary electrophoresis. Buffer total concentration, apparent pH and methanol content, the three most important parameters of the running buffer, were used in triangular resolution mapping to characterize separation. Even though electrophoresis is well known to slow down in partly aqueous media, under our optimized circumstances a baseline separation was achieved within 8 min in each case. PMID:10939454

  19. Electrophoretic mobility patterns of immunologically phenotyped cells in different hemopoietic malignancies.

    PubMed

    Babusíková, O; Koníková, E; Ujházy, P

    1986-01-01

    The electrophoretic mobility distribution along with the immunologic phenotype (rosette tests, surface membrane immunoglobulin determination and mainly the detection of differentiation and leukemia-associated antigens by monoclonal antibodies) have been studied in 120 patients with different hemopoietic cell malignancies and in a group of healthy donors. The aim of our study was to compare the electrophoretic mobility character of malignant cells with that of normal T and B lymphocytes and their immune phenotype. Normal peripheral blood lymphocytes showed the typical bimodal pattern of two clearly distinguishable populations of different electrophoretic mobilities, corresponding to T and B cells. In leukemia and lymphoma cells the sharp unimodal peak has appeared, which was attributed to monoclonal origin of these cells. Moreover, the electrophoretic mobility of cells in different hemopoietic cell malignancies reflected different cell lineages and maturation stages within the given lineage group. Utilizing of the cell electrophoretic mobility as an additional marker to the immunologic data for the characterization of leukemia and lymphoma cells is proposed. PMID:3808126

  20. 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. PMID:25875489

  1. 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.

  2. Sterically stabilized liposomes. Reduction in electrophoretic mobility but not electrostatic surface potential.

    PubMed Central

    Woodle, M C; Collins, L R; Sponsler, E; Kossovsky, N; Papahadjopoulos, D; Martin, F J

    1992-01-01

    The electrophoretic mobility of liposomes containing a negatively charged derivative of phosphatidylethanolamine with a large headgroup composed of the hydrophilic polymer polyethylene glycol (PEG-PE) was determined by Doppler electrophoretic light scattering. The results show that this method is improved by the use of measurements at multiple angles to eliminate artifacts and that very small mobilities can be measured. The electrophoretic mobility of liposomes with 5 to 10 mol% PEG-PE is approximately -0.5 mu ms-1/Vcm-1 regardless of PEG-PE content compared with approximately -2 mu ms-1/Vcm-1 for similar liposomes but containing 7.5% phosphatidylglycerol (PG) instead of PEG-PE. Measurements of surface potential by distribution of an anionic fluorescent probe show that the PEG-PE imparts a negative charge identical to that by PG, consistent with the expectation of similar locations of the ionized phosphate responsible for the charge. The reduced mobility imparted by the surface bound PEG is attributed to a mechanism similar to that described for colloidal steric stabilization: hydrodynamic drag moves the hydrodynamic plane of shear, or the hydrodynamic radius, away from the charge-bearing plane, that of the phosphate moities. An extended length of approximately 50 A for the 2,000 molecular weight PEG is estimated from the reduction in electrophoretic mobility. PMID:1581503

  3. Enhancement of electrophoretic mobility of microparticles near a solid wall--experimental verification.

    PubMed

    Liang, Qian; Zhao, Cunlu; Yang, Chun

    2015-03-01

    Although the existing theories have predicted enhancement of electrophoretic mobility of microparticles near a solid wall, the relevant experimental studies are rare. This is mainly due to difficulties in experimentally controlling and measuring particle-wall separations under dynamic electrophoretic conditions. This paper reports an experimental verification of the enhancement of electrophoretic mobility of a microparticle moving near the wall of a microchannel. This is achieved by balancing dielectrophoretic and lift forces against gravitational force acting on the microparticle so as to control the gap of particle-wall separation. A simple experimental setup is configured and a fabrication method is developed to measure such separation gap. The experiments are conducted for various particle sizes under different electric field strengths. Our experimental results are compared against the available theoretical predictions in the literature. PMID:25421107

  4. 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...

  5. 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...

  6. Antiplasmin activity of electrophoretically separated human serum fractions

    PubMed Central

    Mann, R. D.; Cotton, Susan; Jackson, D.

    1966-01-01

    The antiplasmin which migrates electrophoretically with the alpha2 globulins preponderates in effect over that of the alpha1 migrating antiplasmin. This preponderance persists at physiological pH value in vitro and the significance of this finding is discussed. No evidence has been obtained of the existence of anti-urokinase activity in antiplasmin-free serum fractions. PMID:4160096

  7. Coarse-grained model of conformation-dependent electrophoretic mobility and its influence on DNA dynamics.

    PubMed

    Pandey, Harsh; Underhill, Patrick T

    2015-11-01

    The electrophoretic mobility of molecules such as λ-DNA depends on the conformation of the molecule. It has been shown that electrohydrodynamic interactions between parts of the molecule lead to a mobility that depends on conformation and can explain some experimental observations. We have developed a new coarse-grained model that incorporates these changes of mobility into a bead-spring chain model. Brownian dynamics simulations have been performed using this model. The model reproduces the cross-stream migration that occurs in capillary electrophoresis when pressure-driven flow is applied parallel or antiparallel to the electric field. The model also reproduces the change of mobility when the molecule is stretched significantly in an extensional field. We find that the conformation-dependent mobility can lead to a new type of unraveling of the molecule in strong fields. This occurs when different parts of the molecule have different mobilities and the electric field is large. PMID:26651689

  8. Coarse-grained model of conformation-dependent electrophoretic mobility and its influence on DNA dynamics

    NASA Astrophysics Data System (ADS)

    Pandey, Harsh; Underhill, Patrick T.

    2015-11-01

    The electrophoretic mobility of molecules such as λ -DNA depends on the conformation of the molecule. It has been shown that electrohydrodynamic interactions between parts of the molecule lead to a mobility that depends on conformation and can explain some experimental observations. We have developed a new coarse-grained model that incorporates these changes of mobility into a bead-spring chain model. Brownian dynamics simulations have been performed using this model. The model reproduces the cross-stream migration that occurs in capillary electrophoresis when pressure-driven flow is applied parallel or antiparallel to the electric field. The model also reproduces the change of mobility when the molecule is stretched significantly in an extensional field. We find that the conformation-dependent mobility can lead to a new type of unraveling of the molecule in strong fields. This occurs when different parts of the molecule have different mobilities and the electric field is large.

  9. 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+.

  10. Electrophoretic Mobility of a Dilute, Highly Charged "Soft" Spherical Particle in a Charged Hydrogel.

    PubMed

    Allison, Stuart; Li, Fei; Le, Melinda

    2016-08-25

    In this paper, numerical modeling studies are carried out on the electrophoretic mobility of a dilute, highly charged "soft" spherical particle in a hard hydrogel subjected to a weak, constant, external electric field. The particle contains a solid core with either a uniform charge density or "zeta" potential on its surface. Outside of this lies a charged gel layer of uniform thickness, composition, and charge density. The present work extends previous studies by accounting for the "relaxation effect", or distortion of the charge distribution in the vicinity of the model particle due to the imposition of an external electric and/or flow field. The particle gel layer and ambient hydrogel are modeled as porous Brinkman media. The (steady state) electrodynamic problem is solved at the level of the Poisson equation. Applications emphasize the influence of the relaxation effect and hydrogel charge density on the electrophoretic mobility. PMID:26815300

  11. 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.

  12. Microflora on explanted silicone rubber voice prostheses: taxonomy, hydrophobicity and electrophoretic mobility.

    PubMed

    Neu, T R; Verkerke, G J; Herrmann, I F; Schutte, H K; Van der Mei, H C; Busscher, H J

    1994-05-01

    Silicone rubber voice prostheses are implants which are inserted in a non-sterile environment and therefore become quickly colonized by micro-organisms. The micro-organisms exist on the medical grade silicone rubber as mixed biofilms of bacteria and yeasts. A total of 79 bacterial and 39 yeast strains were isolated from these biofilms by soft ultrasonic treatment. Gram-positive/catalase-negative and Gram-positive/catalase-positive cocci represented the dominant bacterial strains. The yeasts were mainly Candida species. Further characterization of cell surface properties such as hydrophobicity by microbial adhesion to hexadecane and electrophoretic mobility showed a distinct difference when the bacterial strains were compared with the yeasts. The bacterial hydrophobicities ranged from 0 to 100% adhesion to hexadecane, whereas the yeast strains, especially the Candida albicans strains, all had markedly hydrophilic cell surfaces. A comparison of the electrophoretic mobilities showed also differences between bacteria and yeast. The values for the bacteria were found to be between -2.5 to -0.5 (10(-8) m2 V-1 s-1), whereas for the yeasts electrophoretic mobilities were more positive. Based on the adhesive properties of the isolated micro-organisms, strategies can now be developed to modify the properties of the silicone rubber to reduce biofilm formation on such prostheses. PMID:8005837

  13. Antisera against electrophoretically purified tubulin stimulate colchicine-binding activity.

    PubMed

    Aubin, J E; Subrahmanyan, L; Kalnins, V I; Ling, V

    1976-04-01

    Several rabbit antisera have been prepared against reduced and alkylated, electrophoretically purified tubulin isolated from chick brain. These antisera give a single precipitin line in Ouchterlony double diffusion plates when tested against partially purified tubulin, and label specifically microtubule- and tubulin-containing structures, such as mitotic spindles, cilia, and vinblastine-induced crystals, in a variety of cells. The same antisera also display the unique ability to stimulate the colchicine-binding activity of tubulin preparations from chick brain and Chinese hamster ovary tissue culture cells. This specific stimulation of colchicine binding activity is also obtained with the gamma globulin fractions purified by ammonium sulfate precipitation of these antisera. PMID:57619

  14. Approximate Analytic Expression for the Electrophoretic Mobility of Moderately Charged Cylindrical Colloidal Particles.

    PubMed

    Ohshima, Hiroyuki

    2015-12-29

    An approximate analytic expression for the electrophoretic mobility of an infinitely long cylindrical colloidal particle in a symmetrical electrolyte solution in a transverse electric field is obtained. This mobility expression, which is correct to the order of the third power of the zeta potential ζ of the particle, considerably improves Henry's mobility formula correct to the order of the first power of ζ (Proc. R. Soc. London, Ser. A 1931, 133, 106). Comparison with the numerical calculations by Stigter (J. Phys. Chem. 1978, 82, 1417) shows that the obtained mobility formula is an excellent approximation for low-to-moderate zeta potential values at all values of κa (κ = Debye-Hückel parameter and a = cylinder radius). PMID:26639309

  15. 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

  16. Passive trapping of rigid rods due to conformation-dependent electrophoretic mobility.

    PubMed

    Pandey, Harsh; Szafran, Sylvia A; Underhill, Patrick T

    2016-03-16

    We present computer simulations of a rigid rod in a combination of an extensional fluid flow and extensional electric field. The electrophoretic mobility of the rod is different parallel or perpendicular to the rod. The dependence of the mobility on the conformation (orientation) leads to a new phenomenon where the rods can be passively trapped in all directions at the stagnation point. This contrasts with the behavior in either fluid flow or electric field alone, in which an object can be pushed towards the stagnation point along some directions but is pushed away in others. We have determined the state space where trapping occurs and have developed a model that describes the strength of trapping when it does occur. This new phenomenon could be used in the future to separate objects based on a coupling between their mobility and ability to be oriented. PMID:26892384

  17. 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. PMID:19754057

  18. 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

  19. 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

  20. Electrophoretic Mobility Shift Assay (EMSA) for Detecting Protein-Nucleic Acid Interactions

    PubMed Central

    Hellman, Lance M.; Fried, Michael G.

    2009-01-01

    The gel electrophoresis mobility shift assay (EMSA) is used to detect protein complexes with nucleic acids. It is the core technology underlying a wide range of qualitative and quantitative analyses for the characterization of interacting systems. In the classical assay, solutions of protein and nucleic acid are combined and the resulting mixtures are subjected to electrophoresis under native conditions through polyacrylamide or agarose gel. After electrophoresis, the distribution of species containing nucleic acid is determined, usually by autoradiography of 32P-labeled nucleic acid. In general, protein-nucleic acid complexes migrate more slowly than the corresponding free nucleic acid. In this article, we identify the most important factors that determine the stabilities and electrophoretic mobilities of complexes under assay conditions. A representative protocol is provided and commonly used variants are discussed. Expected outcomes are briefly described. References to extensions of the method and a troubleshooting guide are provided. PMID:17703195

  1. Cell surface adhesiveness of mouse sarcoma lines evaluated by latex particle adherence assay: correlation with growth behavior and electrophoretic mobility.

    PubMed

    Bubeník, J; Jandlová, T; Suhajová, E; Malkovský, M

    1979-01-01

    Using the latex particle adherence assay and five mouse sarcoma cell lines of the identical origin, etiology and genotype but differing in malignancy we attempted to correlate the degree of cell surface adhesiveness with growth behavior and electrophoretic mobility of cells. Higher tumorigenicity of four of the cell lines (Mc11--Mc14) was associated with lower cell surface adhesiveness and, conversely, lower malignancy of the fifth line (Mc15) with higher cell surface adhesiveness. No simple correlation or causal relationship was found among the electrophoretic mobility of the lines and other cellular characteristics. PMID:522921

  2. Observation of separate cation and anion electrophoretic mobilities in pure ionic liquids

    NASA Astrophysics Data System (ADS)

    Zhang, Zhiyang; Madsen, Louis A.

    2014-02-01

    Ionic liquids (ILs) continue to show relevance in many fields, from battery electrolytes, to carbon capture, to advanced separations. These highly ion-dense fluids present unique challenges in understanding their electrochemical properties due to deviations in behavior from existing electrolyte theories. Here we present a novel characterization of ILs using electrophoretic NMR (ENMR) to determine separate cation and anion mobilities. This method uses an applied electric field coincident with a pulsed magnetic field gradient to encode the E-field driven flow into NMR signals for cations (1H) and anions (19F). We describe the detailed design of these experiments, including quantitative analysis of artifact mitigation and necessary control experiments. We then explore mobilities and diffusion coefficients for two representative ILs: 1-ethyl-3-methyl imidazolium tetrafluoroborate ([C2mim][BF4]) and 1-ethyl-3-methyl imidazolium trifluoromethanesulfonate ([C2mim][TfO]). We further use the individual ion mobilities to calculate the bulk net conductivity, which closely agrees with bulk conductivity measurements obtained using impedance spectroscopy. These observations represent the first reliable measurements of cation and anion mobilities in pure ILs, with errors of ±7%. We discuss this advanced experimental methodology in detail, as well as implications of these sensitive measurements for understanding conduction mechanisms in ion-dense electrolytes.

  3. Observation of separate cation and anion electrophoretic mobilities in pure ionic liquids.

    PubMed

    Zhang, Zhiyang; Madsen, Louis A

    2014-02-28

    Ionic liquids (ILs) continue to show relevance in many fields, from battery electrolytes, to carbon capture, to advanced separations. These highly ion-dense fluids present unique challenges in understanding their electrochemical properties due to deviations in behavior from existing electrolyte theories. Here we present a novel characterization of ILs using electrophoretic NMR (ENMR) to determine separate cation and anion mobilities. This method uses an applied electric field coincident with a pulsed magnetic field gradient to encode the E-field driven flow into NMR signals for cations ((1)H) and anions ((19)F). We describe the detailed design of these experiments, including quantitative analysis of artifact mitigation and necessary control experiments. We then explore mobilities and diffusion coefficients for two representative ILs: 1-ethyl-3-methyl imidazolium tetrafluoroborate ([C2mim][BF4]) and 1-ethyl-3-methyl imidazolium trifluoromethanesulfonate ([C2mim][TfO]). We further use the individual ion mobilities to calculate the bulk net conductivity, which closely agrees with bulk conductivity measurements obtained using impedance spectroscopy. These observations represent the first reliable measurements of cation and anion mobilities in pure ILs, with errors of ±7%. We discuss this advanced experimental methodology in detail, as well as implications of these sensitive measurements for understanding conduction mechanisms in ion-dense electrolytes. PMID:24588161

  4. Difference in microchip electrophoretic mobility between partially and fully PEGylated poly(amidoamine) dendrimers.

    PubMed

    Park, Eun Ji; Na, Dong Hee

    2015-11-01

    The objective of this study was to investigate the difference in electrophoretic mobility between partially and fully poly(ethylene glycol)-conjugated poly(amidoamine) dendrimers (part-PEG-PAMAM and full-PEG-PAMAM, respectively) using a microchip capillary gel electrophoresis (MCGE). While MCGE allowed size-based separation of PEG-PAMAMs prepared with monomethoxy PEG-nitrophenyl carbonate, full-PEG-PAMAMs migrated slower than part-PEG-PAMAMs that were similar in size or larger. When the measured molecular weights obtained from MCGE analysis and the calculated molecular weights were plotted, each part-PEG-PAMAM and full-PEG-PAMAM showed correlation coefficients greater than 0.98. This study indicates that MCGE would be useful for characterizing PEG-PAMAMs with different PEGylation degrees. PMID:26253023

  5. 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...

  6. 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;…

  7. Electrophoretic mobility shift assays: analysis of tRNA binding to the T box riboswitch antiterminator RNA.

    PubMed

    Anupam, R; Zhou, S; Hines, J V

    2015-01-01

    Changes in electrophoretic mobility upon complex formation with RNA can be used to probe structure-function relationships that are critical for complex formation. Here, we describe the application of this technique to monitor tRNA binding to the T box riboswitch antiterminator RNA. PMID:25352142

  8. 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

  9. 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.

  10. A computer program for determining the electrophoretic mobility of cells in a rectangular chamber during asymmetric electroosmotic flow

    NASA Technical Reports Server (NTRS)

    1985-01-01

    In the field of cell electrophoresis, computer programs have been used for the estimation of zeta potential and surface charge density of specific charged chemical species from electrophoretic mobility data. The union of computer and microscope cell electrophoresis in the laboratory has yielded several satisfying results. The method organizes and error checks these data and stores them on permanent file for future reference or reanalysis. This computer analysis, accomplished in two steps by two main programs and a major subroutine, provides a quick, useful and realistic presentation of mobility data in histogram form, and is appropriate for any microelectrophoretic work using rectangular chambers. Computer program 1 is the first step of two in the analysis of mobility data. Program 2 consists of the main program, POLY2, which fits a least squares parabola to the apparent mobility data generated by Program 1, and the subroutine EXTRA which determines actual cell mobilities using the regression curve equation.

  11. Predicting Electrophoretic Mobility of Protein-Ligand Complexes for Ligands from DNA-Encoded Libraries of Small Molecules.

    PubMed

    Bao, Jiayin; Krylova, Svetlana M; Cherney, Leonid T; Hale, Robert L; Belyanskaya, Svetlana L; Chiu, Cynthia H; Shaginian, Alex; Arico-Muendel, Christopher C; Krylov, Sergey N

    2016-05-17

    Selection of target-binding ligands from DNA-encoded libraries of small molecules (DELSMs) is a rapidly developing approach in drug-lead discovery. Methods of kinetic capillary electrophoresis (KCE) may facilitate highly efficient homogeneous selection of ligands from DELSMs. However, KCE methods require accurate prediction of electrophoretic mobilities of protein-ligand complexes. Such prediction, in turn, requires a theory that would be applicable to DNA tags of different structures used in different DELSMs. Here we present such a theory. It utilizes a model of a globular protein connected, through a single point (small molecule), to a linear DNA tag containing a combination of alternating double-stranded and single-stranded DNA (dsDNA and ssDNA) regions of varying lengths. The theory links the unknown electrophoretic mobility of protein-DNA complex with experimentally determined electrophoretic mobilities of the protein and DNA. Mobility prediction was initially tested by using a protein interacting with 18 ligands of various combinations of dsDNA and ssDNA regions, which mimicked different DELSMs. For all studied ligands, deviation of the predicted mobility from the experimentally determined value was within 11%. Finally, the prediction was tested for two proteins and two ligands with a DNA tag identical to those of DELSM manufactured by GlaxoSmithKline. Deviation between the predicted and experimentally determined mobilities did not exceed 5%. These results confirm the accuracy and robustness of our model, which makes KCE methods one step closer to their practical use in selection of drug leads, and diagnostic probes from DELSMs. PMID:27119259

  12. Mapping DNA Quantity into Electrophoretic Mobility through Quantum Dot Nanotethers for High Resolution Genetic and Epigenetic Analysis

    PubMed Central

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

    2011-01-01

    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 (QD) 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 quantum dot 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. PMID:22136600

  13. 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

  14. Solubilization of Minerals by Bacteria: Electrophoretic Mobility of Thiobacillus ferrooxidans in the Presence of Iron, Pyrite, and Sulfur

    PubMed Central

    Blake, Robert C.; Shute, Elizabeth A.; Howard, Gary T.

    1994-01-01

    Thiobacillus ferroxidans is an obligate acidophile that respires aerobically on pyrite, elemental sulfur, or soluble ferrous ions. The electrophoretic mobility of the bacterium was determined by laser Doppler velocimetry under physiological conditions. When grown on pyrite or ferrous ions, washed cells were negatively charged at pH 2.0. The density of the negative charge depended on whether the conjugate base was sulfate, perchlorate, chloride, or nitrate. The addition of ferric ions shifted the net charge on the surface asymptotically to a positive value. When grown on elemental sulfur, washed cells were close to their isoelectric point at pH 2.0. Both pyrite and colloidal sulfur were negatively charged under the same conditions. The electrical double layer around the bacterial cells under physiological conditions exerted minimal electrostatic repulsion in possible interactions between the cell and either of its charged insoluble substrates. When Thiobacillus ferrooxidans was mixed with either pyrite or colloidal sulfur at pH 2.0, the mobility spectra of the free components disappeared with time to be replaced with a new colloidal particle whose electrophoretic properties were intermediate between those of the starting components. This new particle had the charge and size properties anticipated for a complex between the bacterium and its insoluble substrates. The utility of such measurements for the study of the interactions of chemolithotrophic bacteria with their insoluble substrates is discussed. Images PMID:16349387

  15. Electrophoretic mobility of concentrated carbon black dispersions in a low-permittivity solvent by optical coherence tomography.

    PubMed

    Patel, Mehul N; Smith, P Griffin; Kim, Jihoon; Milner, Thomas E; Johnston, Keith P

    2010-05-15

    Electrophoretic mobilities of concentrated dispersions of carbon black particles in a low-permittivity solvent were measured using differential-phase optical coherence tomography (DP-OCT). An electrode spacing of only 0.18 mm enables measurement of highly concentrated dispersions up to 1 wt.% of highly absorbing carbon black particles with high electric fields at low potentials. The capabilities of this DP-OCT method, including high sensitivity, high spatial resolution, and strong electric fields, enable enhanced measurement of low electrophoretic mobilities encountered in low-permittivity solvents. The zeta potential of carbon black particles ranged from -24 mV to -12 mV as the concentration of surfactant sodium bis(2-ethyl-1-hexyl)sulfosuccinate (AOT) was increased from 1 mM to 100 mM. A mechanism is presented to explain the electrostatic charging of carbon black particles in terms of the partitioning of the ions between the reverse micelles in the double layer and the surfactant adsorbed on the particle surface, as AOT concentration is varied. PMID:20176365

  16. 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

  17. Affinity Capillary Electrophoresis for Selective Control of Electrophoretic Mobility of Sialic Acid Using Lanthanide-Hexadentate Macrocyclic Polyazacarboxylate Complexes.

    PubMed

    Goto, Daiki; Ouchi, Kazuki; Shibukawa, Masami; Saito, Shingo

    2015-01-01

    It is difficult to control the electrophoretic mobility in order to obtain high resolution among saccharides in complex samples. We report herein on a new affinity capillary electrophoresis (ACE) method for an anionic monosaccharide, N-acetylneuraminic acid (Neu5Ac), which is important in terms of pathological diagnosis, using lanthanide-hexadentate macrocyclic polyazacarboxylate complexes (Ln-NOTA) as affinity reagents. It was shown that Ln-NOTA complexes increased the anionic mobility of Neu5Ac by approximately 40% through selective complexation with Neu5Ac. The extent of change in the mobility strongly depended on the type of central metal ion of Ln-NOTA. The stability constant (K) of Lu-NOTA with Neu5Ac was determined by ACE to be log Kb = 3.62 ± 0.04, which is the highest value among artificial receptors for Neu5Ac reported so far. Using this ACE, the Neu5Ac content in a glycoprotein sample, α1-acid glycoprotein (AGP), was determined after acid hydrolysis. Complete separation between Neu5Ac and hydrolysis products was successful by controlling the mobility to determine the concentration of Neu5Ac. PMID:26561258

  18. Non-monotonic mobility vs. length dependence observed in electrophoretic separation of 25 bp DNA ladder in Pluronic gels.

    NASA Astrophysics Data System (ADS)

    You, Seungyong; van Winkle, David

    2009-03-01

    We electrophoresed a double-stranded DNA ladder first in an agarose gel, then in gels of Pluronic F-127 at room temperature. The DNA ladder consisted of 19 discrete fragments ranging in length from 25 to 450 bp at 25 bp increments plus 500 bp. The DNA fragments were first separated in agarose gel and stacked normally with 25 bp having the highest mobility. A single lane of the separated DNA ladder in the agarose gel was inserted at the edge of a Pluronic gel slab. The DNA was electrophoresed from the agarose into the Pluronic gels perpendicular to the original separation axis. Mobilities of DNA fragments increased from 25 bp to 175 bp and then decreased from 175 bp to 500 bp. The 25 bp and 500 bp bands of the ladder had approximately the same mobility in several different Pluronic gel concentrations. Both were slower than most bands in between. The highest mobility fragments with length of 175 bp have 59.5 nm contour length which is about 3.5 times the diameter of a micelle (17 nm). This result suggests a crossover from chromatographic separation to electrophoretic separation for these short DNAs. This research is supported by the state of Florida (Martech) and Research Corporation.

  19. Comprehensive size-determination of whole virus vaccine particles using gas-phase electrophoretic mobility macromolecular analyzer, atomic force microscopy, and transmission electron microscopy.

    PubMed

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

    2015-09-01

    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

  20. 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

  1. Patterns of Molecular Variation. II. Associations of Electrophoretic Mobility and Larval Substrate within Species of the DROSOPHILA MULLERI Complex

    PubMed Central

    Richardson, R. H.; Smouse, Peter E.; Richardson, Martha E.

    1977-01-01

    Electromorphic variation among populations of Drosophila mojavensis, D. arizonensis and D. longicornis was examined for seven genetic loci. The average electrophoretic mobility for a population was used as the metric. D. mojavensis and D. arizonensis use larval substrates in different parts of their geographic ranges, while D. longicornis is more narrowly restricted to different species of the cactus Opuntia in different localities. There is marked electromorphic variation among populations of either D. mojavensis or D. arizonensis, and the bulk of this variation is accounted for by differences in laval substrate. There is somewhat less variation among populations of D. longicornis, and only a moderate portion of this is accounted for by larval substrate differences. There appears to be an association between the taxonomic diversity of the larval substrates and the electromorphic diversity of the Drosophila populations utilizing those substrates. Evidence is reviewed that suggests physiological mechanisms for these possibly adaptive associations. PMID:838268

  2. Characterization of the cell surface properties of drinking water pathogens by microbial adhesion to hydrocarbon and electrophoretic mobility measurements.

    PubMed

    Popovici, Jonathan; White, Colin P; Hoelle, Jill; Kinkle, Brian K; Lytle, Darren A

    2014-06-01

    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 aggregation, adhesion to surfaces, and stability of the cells within the aqueous environments. These cell characteristics are unique to the bacterial species and are a reflection of the large diversity of surface structures, proteins, and appendages of microorganisms. CSH and EPM of bacterial cells contribute substantially to the effectiveness of drinking water treatment to remove them, and therefore an investigation of these properties will be useful in predicting their removal through drinking water treatment processes and transport through drinking water distribution systems. EPM and CSH measurements of six microbiological pathogen or surrogate species suspended in phosphate-buffered water are reported in this work. Two strains of Vibrio cholerae were hydrophobic, while three strains of Escherichia coli were hydrophilic. Bacillus cereus was categorized as moderately hydrophobic. The strains of E. coli had the highest (most negative) EPM. Based on the measurements, E. coli species is predicted to be most difficult to remove from water while V. cholerae will be the easiest to remove. PMID:24815929

  3. Capillary electrophoretic and extraction conditions for the analysis of Catha edulis FORKS active principles.

    PubMed

    Roda, Gabriella; Liberti, Vincenzo; Arnoldi, Sebastiano; Argo, Antonella; Rusconi, Chiara; Suardi, Sonia; Gambaro, Veniero

    2013-05-10

    A capillary electrophoretic method, which allowed the detection and separation of the active principles of Catha edulis, i.e. cathinone, cathine and phenylpropanolamine, was developed. A suitable internal standard (nicotinamide), which permitted the quantification of the analytes reducing the variability of the migration times due to EOF changes, was identified. The analytical method was validated, assessing linearity, sensitivity and repeatability, showing optimal features for the analysis of the vegetable material. Moreover extraction conditions were investigated to achieve the exhaustion of the plant material in the fastest and most efficient way to meet the requirements of the Court. PMID:23597752

  4. Determination of electrophoretic mobilities and hydrodynamic radii of three humic substances as a function of pH and ionic strength.

    PubMed

    Hosse, M; Wilkinson, K J

    2001-11-01

    Capillary electrophoresis (CE) and fluorescence correlation spectroscopy (FCS) were employed to determine electrophoretic mobilities and hydrodynamic sizes of three humic substances (IHSS aquatic fulvic acid (FA), IHSS aquatic humic acid (HA), and IHSS peat humic acid (PHA)) as a function of pH and ionic strength. A slight aggregation corresponding to the formation of dimers and trimers was observed at low pH using fluorescence correlation spectroscopy (FCS). For example, for the peat humic acid, diffusion coefficients decreased from 2.1 x 10(-10) m2 s(-1) at pH 4 to 2.4 x 10(-10) m2 s(-1) at pH 11. For all three humic substances, electrophoretic mobilities were also shown to decrease significantly below pH 6. Calculated zeta potentials observed at high pH of -69 mV (FA), -62 mV (HA), and -63 mV (PHA) decreased to -39, -50, and -47 mV, respectively, under slightly acidic pH (4.5-4.8) conditions. No evidence of ionic strength induced aggregation was found using fluorescence correlation spectroscopy (FCS); diffusion coefficients increased slightly (<25%) with increasing ionic strength (up to 1 M). Negative electrophoretic mobilities decreased to a maximum measured ionic strength of 0.18 M. Above this ionic strength, no peaks were observed due to an increased HS adsorption to the capillary wall and an important decrease in electroosmotic flow. Interpretation of electrophoretic mobilities determined by CE is complicated by the fact that under certain conditions, HS appeared to be complexed by CE buffer systems, including MES, BES, and AMPSO. PMID:11718346

  5. [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

  6. Estimation of electrokinetic and hydrodynamic global properties of relevant amyloid-beta peptides through the modeling of their effective electrophoretic mobilities and analysis of their propensities to aggregation.

    PubMed

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

    2014-09-01

    Neuronal activity loss may be due to toxicity caused by amyloid-beta peptides forming soluble oligomers. Here amyloid-beta peptides (1-42, 1-40, 1-39, 1-38, and 1-37) are characterized through the modeling of their experimental effective electrophoretic mobilities determined by a capillary zone electrophoresis method as reported in the literature. The resulting electrokinetic and hydrodynamic global properties are used to evaluate amyloid-beta peptide propensities to aggregation through pair particles interaction potentials and Brownian aggregation kinetic theories. Two background electrolytes are considered at 25°C, one for pH 9 and ionic strength I = 40 mM (aggregation is inhibited through NH4OH) the other for pH 10 and I = 100 mM (without NH4OH). Physical explanations of peptide oligomerization mechanisms are provided. The effect of hydration, electrostatic, and dispersion forces in the amyloidogenic process of amyloid-beta peptides (1-40 and 1-42) are quantitatively presented. The interplay among effective charge number, hydration, and conformation of chains is described. It is shown that amyloid-beta peptides (1-40 and 1-42) at pH 10, I = 100 mM and 25°C, may form soluble oligomers, mainly of order 2 and 4, after an incubation of 48 h, which at higher times evolve and end up in complex structures (protofibrils and fibrils) found in plaques associated with Alzheimer's disease. PMID:24975363

  7. 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

  8. Alpha chain hemoglobins with electrophoretic mobility similar to that of hemoglobin S in a newborn screening program

    PubMed Central

    Silva, Marcilene Rezende; Sendin, Shimene Mascarenhas; Araujo, Isabela Couto de Oliveira; Pimentel, Fernanda Silva; Viana, Marcos Borato

    2013-01-01

    Objective To characterize alpha-chain variant hemoglobins with electric mobility similar to that of hemoglobin S in a newborn screening program. Methods βS allele and alpha-thalassemia deletions were investigated in 14 children who had undefined hemoglobin at birth and an electrophoretic profile similar to that of hemoglobin S when they were six months old. Gene sequencing and restriction enzymes (DdeI, BsaJI, NlaIV, Bsu36I and TaqI) were used to identify hemoglobins. Clinical and hematological data were obtained from children who attended scheduled medical visits. Results The following alpha chain variants were found: seven children with hemoglobin Hasharon [alpha2 47(CE5) Asp>His, HbA2:c.142G>C], all associated with alpha-thalassemia, five with hemoglobin Ottawa [alpha1 15(A13) Gly>Arg, HBA1:c.46G>C], one with hemoglobin St Luke's [alpha1 95(G2) Pro>Arg, HBA1:c.287C>G] and another one with hemoglobin Etobicoke [alpha212 84(F5) Ser>Arg, HBA212:c.255C>G]. Two associations with hemoglobin S were found: one with hemoglobin Ottawa and one with hemoglobin St Luke's. The mutation underlying hemoglobin Etobicoke was located in a hybrid α212 allele in one child. There was no evidence of clinically relevant hemoglobins detected in this study. Conclusion Apparently these are the first cases of hemoglobin Ottawa, St Luke's, Etobicoke and the α212 gene described in Brazil. The hemoglobins detected in this study may lead to false diagnosis of sickle cell trait or sickle cell disease when only isoelectric focusing is used in neonatal screening. Additional tests are necessary for the correct identification of hemoglobin variants. PMID:23741188

  9. Photoaffinity electrophoretic mobility shift assay using photoreactive DNA bearing 3-trifluoromethyl-3-phenyldiazirine in its phosphate backbone.

    PubMed

    Sadakane, Yutaka; Hatanaka, Yasumaru

    2016-08-01

    Photoaffinity cross-linking enables the analysis of interactions between DNA and proteins even under denaturing conditions. We present a photoaffinity electrophoretic mobility shift assay (EMSA) in which two heterogeneous techniques-photoaffinity cross-linking using DNA bearing 3-trifluoromethyl-3-phenyldiazirine and sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) analysis-are combined. To prepare the photoreactive DNA, which is an essential tool for photoaffinity EMSA, we first determined the optimal conditions for the integration of 4-(3-trifluoromethyl-3H-diazirin-3-yl)benzyl bromide to the specific site of oligonucleotide where phosphodiester linkage was replaced with phosphorothioate linkage. The photoaffinity EMSA was developed using the POU (initial letters of three genes: Pit-l, Oct-1,2, and unc-86) domain region of Oct-1 protein, which specifically bound to octamer DNA motif (ATGCAAAT). The affinity-purified recombinant POU domain proteins conjugated with glutathione-S-transferase (GST) contained three distinct proteins with molecular weights of 34, 36, and 45 kDa. The photoaffinity EMSA could clearly distinguish the individual binding abilities of three proteins on a single lane and showed that the whole POU domain protein specifically bound to octamer DNA motif by competition experiments. Using the nuclear extract of HeLa cells, the photoaffinity EMSA revealed that at least five specific proteins could bind to the octamer DNA motif. These results show that photoaffinity EMSA using 3-trifluoromethyl-3-phenyldiazirine can provide high-performance analysis of DNA-binding proteins. PMID:27156811

  10. 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.

  11. 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.

  12. Global properties and propensity to dimerization of the amyloid-beta (12-28) peptide fragment through the modeling of its monomer and dimer diffusion coefficients and electrophoretic mobilities.

    PubMed

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

    2015-03-01

    Neuronal activity loss may be due to toxicity caused mainly by amyloid-beta (1-40) and (1-42) peptides forming soluble oligomers. Here the amyloid-beta (12-28) peptide fragment (monomer) and its dimer are characterized at low pH through the modeling of their diffusion coefficients and effective electrophoretic mobilities. Translational diffusion coefficient experimental values of monomer and dimer analogs of this peptide fragment and monomer and dimer mixtures at thermodynamic equilibrium are used as reported in the literature for different monomer initial concentrations. The resulting electrokinetic and hydrodynamic global properties are employed to evaluate the amyloid-beta (12-28) peptide fragment propensity to dimerization through a thermodynamic theoretical framework. Therefore equilibrium constants are considered at pH 2.9 to elucidate one of the amyloidogenic mechanisms involving the central hydrophobic region LVFFA of the peptide spanning residues 17-21 associated with phenylalanine at positions 19 and 20 in the amino acid sequence of amyloid-beta peptides. An analysis demonstrating that peptide aggregation is a concentration-dependent process is provided, where both pair and intraparticle charge regulation phenomena become relevant. It is shown that the modeling of the effective electrophoretic mobility of the amyloid-beta (12-28) peptide fragment is crucial to understand the effect of hydrophobic region LVFFA in the amyloidogenic process. PMID:25403948

  13. Determination of beta-hydroxyacyl CoA-dehydrogenase activity in meat by electrophoretically mediated microanalysis.

    PubMed

    Vallejo-Cordoba, Belinda; Mazorra-Manzano, Miguel A; González-Córdova, Aarón F

    2003-01-01

    The combined use of an in-tube enzyme assay and capillary electrophoresis for determining beta-hydroxyacyl CoA-dehydrogenase (beta-HADH) activity in meat was investigated. Beta-HADH is a significant mitochondrial enzyme in food muscle; thus, the determination of its activity is important in food analysis. The enzymatic assay and the separation of the reaction products were carried out by electrophoretically mediated microanalysis (EMMA) using a plug-plug reaction mode at variable potential. For the quantification of beta-HADH activity, the rate of conversion of reduced beta-nicotinamide adenine dinucleotide (NADH) to beta-nicotinamide adenine dinucleotide (NAD+) was calculated by determining NAD+ at 260 nm. A calibration curve for NAD+ concentration versus normalized areas showed a highly significant (p < 0.001) linear relationship (R2 = 0.993). Accurate quantification of beta-HADH activity was achieved since on-line monitoring allowed us to account for the NAD+ produced from NADH degradation by applying a correction factor. An average reaction time of 0.66 +/- 0.06 sec was determined for a protein concentration in the range of 0.1-0.5 mg protein/mL. The assay was reproducible since coefficients of variation of less than 6.2% were calculated for triplicate analyses. PMID:14596340

  14. 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

  15. Physical Activity Helps Seniors Stay Mobile

    MedlinePlus

    ... External link, please review our exit disclaimer . Subscribe Physical Activity Helps Seniors Stay Mobile A carefully structured, moderate physical activity program helped vulnerable older people maintain their mobility. ...

  16. Impact of chemical and structural anisotropy on the electrophoretic mobility of spherical soft multilayer particles: the case of bacteriophage MS2.

    PubMed

    Langlet, Jérémie; Gaboriaud, Fabien; Gantzer, Christophe; Duval, Jérôme F L

    2008-04-15

    We report a theoretical investigation of the electrohydrodynamic properties of spherical soft particles composed of permeable concentric layers that differ in thickness, soft material density, chemical composition, and flow penetration degree. Starting from a recent numerical scheme developed for the computation of the direct-current electrophoretic mobility (mu) of diffuse soft bioparticles, the dependence of mu on the electrolyte concentration and solution pH is evaluated taking the known three-layered structure of bacteriophage MS2 as a supporting model system (bulk RNA, RNA-protein bound layer, and coat protein). The electrokinetic results are discussed for various layer thicknesses, hydrodynamic flow penetration degrees, and chemical compositions, and are discussed on the basis of the equilibrium electrostatic potential and hydrodynamic flow field profiles that develop within and around the structured particle. This study allows for identifying the cases where the electrophoretic mobility is a function of the inner structural and chemical specificity of the particle and not only of its outer surface properties. Along these lines, we demonstrate the general inapplicability of the notions of zeta potential (zeta) and surface charge for quantitatively interpreting electrokinetic data collected for such systems. We further shed some light on the physical meaning of the isoelectric point. In particular, numerical and analytical simulations performed on structured soft layers in indifferent electrolytic solution demonstrate that the isoelectric point is a complex ionic strength-dependent signature of the flow permeation properties and of the chemical and structural details of the particle. Finally, the electrophoretic mobilities of the MS2 virus measured at various ionic strength levels and pH values are interpreted on the basis of the theoretical formalism aforementioned. It is shown that the electrokinetic features of MS2 are to a large extent determined not only

  17. Impact of Chemical and Structural Anisotropy on the Electrophoretic Mobility of Spherical Soft Multilayer Particles: The Case of Bacteriophage MS2

    PubMed Central

    Langlet, Jérémie; Gaboriaud, Fabien; Gantzer, Christophe; Duval, Jérôme F. L.

    2008-01-01

    We report a theoretical investigation of the electrohydrodynamic properties of spherical soft particles composed of permeable concentric layers that differ in thickness, soft material density, chemical composition, and flow penetration degree. Starting from a recent numerical scheme developed for the computation of the direct-current electrophoretic mobility (μ) of diffuse soft bioparticles, the dependence of μ on the electrolyte concentration and solution pH is evaluated taking the known three-layered structure of bacteriophage MS2 as a supporting model system (bulk RNA, RNA-protein bound layer, and coat protein). The electrokinetic results are discussed for various layer thicknesses, hydrodynamic flow penetration degrees, and chemical compositions, and are discussed on the basis of the equilibrium electrostatic potential and hydrodynamic flow field profiles that develop within and around the structured particle. This study allows for identifying the cases where the electrophoretic mobility is a function of the inner structural and chemical specificity of the particle and not only of its outer surface properties. Along these lines, we demonstrate the general inapplicability of the notions of zeta potential (ζ) and surface charge for quantitatively interpreting electrokinetic data collected for such systems. We further shed some light on the physical meaning of the isoelectric point. In particular, numerical and analytical simulations performed on structured soft layers in indifferent electrolytic solution demonstrate that the isoelectric point is a complex ionic strength-dependent signature of the flow permeation properties and of the chemical and structural details of the particle. Finally, the electrophoretic mobilities of the MS2 virus measured at various ionic strength levels and pH values are interpreted on the basis of the theoretical formalism aforementioned. It is shown that the electrokinetic features of MS2 are to a large extent determined not only by

  18. AN ELECTROPHORETIC STUDY OF A STREPTOCOCCAL PROTEINASE AND ITS PRECURSOR

    PubMed Central

    Shedlovsky, Theodore; Elliott, S. D.

    1951-01-01

    An electrophoretic study of crystalline preparations of a streptococcal proteinase and its precursor established their isoelectric points at pH values of 8.42 and 7.35 respectively (ionic strength 0.10). Preparations of the proteinase appeared to be electrophoretically homogeneous over a pH range of 5 to 8.5. Precursor preparations contained a relatively low concentration of the active enzyme visible as a separate peak in electrophoretic patterns of sufficiently concentrated solutions. Autocatalytic conversion of precursor to active enzyme was complete and resulted in a corresponding change in the electrophoretic pattern. Treatment of precursor preparations with trypsin produced incomplete conversion to the active enzyme and resulted in the formation of a modified precursor protein. This differed from the parent substance in electrophoretic mobility and in susceptibility to trypsin, but resembled it in immunological specificity and, as previously shown, in susceptibility to conversion to active enzyme by autocatalysis. Serological reactions of precursor and active enzyme components withdrawn from the cell after electrophoresis are described. It appears that the precursor protein may have two antigenic groups, one specific, the other shared by the active enzyme which behaves as a single antigen. PMID:14888818

  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. PMID:26999801

  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. PMID:26383237

  1. Measurement of Electrophoretic Mobility of Human Promyelocytic Leukemia Cell Lines (HL60) During Neutrophil Differentiation Using On-Chip Cell Electrophoresis

    NASA Astrophysics Data System (ADS)

    Matsuhashi, Ryutaro; Akagi, Takanori; Ichiki, Takanori

    Electrophoretic mobility (EPM) of human promyelocytic leukemia cell lines (HL60) during neutrophil differentiation induced by all-trans retinoic acid (ATRA) or dimethyl sulfoxide (DMSO) was measured using microcapillary electrophoresis chips. Prior to EPM measurement of HL60 cells, neutrophil differentiation of the cells was confirmed by morphological classification. Subsequently, EPM of HL60 cells was measured using an on-chip cell electrophoresis system before and after neutrophil differentiation. The EPM changed gradually with the progress of the neutrophil differentiation. From the analysis of experimental data by principal component analysis, it was revealed that there is a strong correlation between morphologic classification and EPM during the neutrophilic differentiation. The present result suggests that on-chip EPM measurement system can be used as a monitoring tool for the cell differentiation.

  2. Analysis of a Common Cold Virus and Its Subviral Particles by Gas-Phase Electrophoretic Mobility Molecular Analysis and Native Mass Spectrometry

    PubMed Central

    2015-01-01

    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. PMID:26221912

  3. Electrophoretic cell separation by means of microspheres

    NASA Technical Reports Server (NTRS)

    Smolka, A. J. K.; Nerren, B. H.; Margel, S.; Rembaum, A.

    1979-01-01

    The electrophoretic mobility of fixed human erythrocytes immunologically labeled with poly(vinylpyridine) or poly(glutaraldehyde) microspheres was reduced by approximately 40%. This observation was utilized in preparative scale electrophoretic separations of fixed human and turkey erythrocytes, the mobilities of which under normal physiological conditions do not differ sufficiently to allow their separation by continuous flow electrophoresis. We suggest that resolution in the electrophoretic separation of cell subpopulations, currently limited by finite and often overlapping mobility distributions, may be significantly enhanced by immunospecific 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. The pH dependence of predictive models relating electrophoretic mobility to peptide chemico-physical properties in capillary zone electrophoresis.

    PubMed

    Castagnola, M; Rossetti, D V; Corda, M; Pellegrini, M; Misiti, F; Olianas, A; Giardina, B; Messana, I

    1998-10-01

    We applied best fitting procedures to capillary electrophoresis (CE) mobility values, measured at varying acidic pH, of a set of 21 peptides with a molecular mass ranging from about 350 to 1850 Da. This method allowed the contemporary measurements of C-terminus and carboxylic group of the side-chain of aspartic and glutamic acid dissociation constants and of peptide Stokes radius at different protonation stages. Stokes radius was related to peptide molecular mass M at the power of a fractional coefficient, and best correlation was found at pH 2.25, the fractional coefficient being equal to 0.68. This value is close to that proposed by R. E. Offord (Nature 1966, 211, 591-593), who suggested a proportionality between the polymer Stokes radius and M(2/3). The coefficient value decreases at higher pH, reaching a value of 0.58 at pH 4.25, corresponding to a mean peptide conformational transition towards more compact structures as a consequence of C-terminus dissociation. The measurement of the dissociation constants of each peptide allowed us to determine the percentage error on peptide charge predictions performed utilizing mean dissociation constants. Even for the charge, the best predictive performance is obtained at the most acidic edge of the range of the pH studied, mainly at pH 2.25. Conclusively, this study shows that the best performance of predictive models for peptide CE mobility is obtainable in the very acidic pH range (2.25-2.50) and in the absence of electroosmotic flow, and that a satisfactory predictive equation of peptide electrophoretic mobility (m2V(-1)s(-1) is given by mu = 85.4(Z/M(0.68))10(-8). PMID:9788308

  7. 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.

  8. Identification and secondary structure analysis of a region affecting electrophoretic mobility of the STR locus SE33.

    PubMed

    Wang, Dennis Y; Green, Robert L; Lagacé, Robert E; Oldroyd, Nicola J; Hennessy, Lori K; Mulero, Julio J

    2012-05-01

    SE33 is one of the most informative markers in forensic use due to its high power of discrimination. During the course of developing the AmpFℓSTR(®) NGM SElect™ PCR Amplification Kit several SE33 primer designs were screened with one primer pair yielding a high frequency of discordant alleles when compared to the AmpFℓSTR(®) SEfiler Plus™ PCR Amplification Kit. This discordance was mostly specific to samples of African descent with an estimated frequency of 5.1% and was a result of a mobility shift of approximately +0.84nt. The sequence analysis of the affected alleles revealed that the only difference from the wild type sequence was a single nucleotide polymorphism (SNP) outside of the SE33 repeat but within the amplicon of this particular set of experimental primers. In total, we identified three different SNPs all within 9nt of each other, each of which could cause the mobility shift individually. Further characterization of this region via site directed mutagenesis and thermostability measurements strongly suggests that this polymorphic region contains a secondary structure that, when disrupted due to the presence of a variant SNP, results in a mobility shift relative to the wild type sequence. To overcome this problem, the SE33 primers used in the final configuration of the NGM SElect™ Kit avoided the amplification of this polymorphic region yielding in turn results highly concordant with the SEfiler Plus™ Kit. PMID:21757416

  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. Charge regulation phenomenon predicted from the modeling of polypeptide electrophoretic mobilities as a relevant mechanism of amyloid-beta peptide oligomerization.

    PubMed

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

    2016-03-01

    Electrophoretic mobilities of amyloid-beta (1-40) and (1-42) peptides and their aggregates are modeled to study the amyloidogenic pathway associated with Alzheimer´s Disease. The near molecule pH generated by the intraparticle charge regulation phenomenon during the oligomerization of amyloid-beta (1-40) and (1-42) peptides is evaluated and discussed as a relevant mechanism supporting the "amyloid cascade hypothesis" proposed in the literature. A theoretical framework associated with the oligomerization of amyloid-beta peptides including simple scaling laws and the consideration of electrokinetic and hydrodynamic global properties of oligomers is presented. The central finding is the explanation of the near molecule pH change toward the pI when the oligomerization number increases. These results allow one to rationalize consecutive physical stages that validate the amyloid cascade hypothesis. Concluding remarks involving mainly the effects of pair and intraparticle charge regulation phenomena on the amyloidogenic pathway with some suggestions for future research are provided. PMID:26718015

  11. A68 proteins in Alzheimer's disease are composed of several tau isoforms in a phosphorylated state which affects their electrophoretic mobilities.

    PubMed Central

    Brion, J P; Hanger, D P; Couck, A M; Anderton, B H

    1991-01-01

    The tau-immunoreactive A68 polypeptides found in brains from patients with Alzheimer's disease have been studied by Western blotting using (1) antibodies to synthetic peptides corresponding to sequences that span the complete human tau molecule, and (2) antibodies specific for inserts 1 and 2 found towards the N-terminus of some tau isoforms. The three major A68 polypeptides were labelled by all of the antibodies to sequences common to all tau isoforms, but the faster-migrating A68 polypeptides was not labelled by either of the two antibodies specific for inserts 1 and 2. Treatment with alkaline phosphatase of non-solubilized A68 did not change its electrophoretic mobility on SDS/PAGE under the conditions described here. However, A68 that was solubilized before treating it with alkaline phosphatase was found to move faster on SDS/PAGE than untreated A68, to a position similar to that of normal tau. We also confirmed that A68 preparations contain numerous paired helical filaments (PHF). These PHF were labelled by all anti-tau antibodies, including insert-specific antibodies. Our results further support the notion that PHF contain abnormally phosphorylated tau in an aggregated state, and indicate that these abnormally phosphorylated tau forms are composed of several tau isoforms and that the full length of the tau molecule is present in these polypeptides. Images Fig. 2. Fig. 3. Fig. 4. Fig. 5. Fig. 6. PMID:1953678

  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 semi-flexible double-stranded DNA in defect-controlled polymer networks: Mechanism investigation and role of structural parameters

    NASA Astrophysics Data System (ADS)

    Khairulina, Kateryna; Li, Xiang; Nishi, Kengo; Shibayama, Mitsuhiro; Chung, Ung-il; Sakai, Takamasa

    2015-06-01

    Our previous studies have reported an empirical model, which explains the electrophoretic mobility (μ) of double-stranded DNA (dsDNA) as a combination of a basic migration term (Rouse-like or reptation) and entropy loss term in polymer gels with ideal network structure. However, this case is of exception, considering a large amount of heterogeneity in the conventional polymer gels. In this study, we systematically tune the heterogeneity in the polymer gels and study the migration of dsDNA in these gels. Our experimental data well agree with the model found for ideal networks. The basic migration mechanism (Rouse-like or reptation) persists perfectly in the conventional heterogeneous polymer gel system, while the entropy loss term continuously changes with increase in the heterogeneity. Furthermore, we found that in the limit where dsDNA is shorter than dsDNA persistence length, the entropy loss term may be related to the collisional motions between DNA fragments and the cross-links.

  14. On electrophoretic NMR. Exploring high conductivity samples

    NASA Astrophysics Data System (ADS)

    Bielejewski, Michał; Giesecke, Marianne; Furó, István

    2014-06-01

    The performance of a new electrophoretic NMR (eNMR) method that uses a Carr-Purcell-Meiboom-Gill echo train with repeated electric field reversal is investigated. We show that this pulse sequence, with acronym CPMGER, yields strongly reduced artifacts from convective flow effects caused by the simultaneous presence of electroosmotic and thermal driving forces. We demonstrate the achieved improvements in various aqueous solutions. Ultimately, the method can be used for obtaining electrophoretic mobilities by eNMR without relying on uncharged reference molecules, otherwise a significant limitation for electrophoretic experiments performed with nuclei other than 1H.

  15. 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. PMID:25789885

  16. 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. PMID:26674535

  17. 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

  18. Electrophoretic Deposition for Fabricating Microbatteries

    NASA Technical Reports Server (NTRS)

    West, William; Whitacre, Jay; Bugga, Ratnakumar

    2003-01-01

    An improved method of fabrication of cathodes of microbatteries is based on electrophoretic deposition. Heretofore, sputtering (for deposition) and the use of photoresist and liftoff (for patterning) have been the primary methods of fabricating components of microbatteries. The volume of active electrode material that can be deposited by sputtering is limited, and the discharge capacities of prior microbatteries have been limited accordingly. In addition, sputter deposition is slow. In contrast, electrophoretic deposition is much faster and has shown promise for increasing discharge capacities by a factor of 10, relative to those of microbatteries fabricated by prior methods.

  19. 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…

  20. 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)

  1. 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.

  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. 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

  4. 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

  5. Electrophoretic transport of biomolecules across liquid-liquid interfaces.

    PubMed

    Hahn, Thomas; Münchow, Götz; Hardt, Steffen

    2011-05-11

    The mass transfer resistance of a liquid-liquid interface in an aqueous two-phase system composed of poly(ethylene glycol) and dextran is investigated. Different types of proteins and DNA stained with fluorescent dyes serve as probes to study the transport processes close to the interface. A microfluidic device is employed to enable the electrophoretic transport of biomolecules from one phase to another. The results obtained for proteins can be explained solely via the different electrophoretic mobilities and different affinities of the molecules to the two phases, without any indications of a significant mass transfer resistance of the liquid-liquid interface. By contrast, DNA molecules adsorb to the interface and only desorb under an increased electric field strength. The desorption process carries the signature of a thermally activated escape from a metastable state, as reflected in the exponential decay of the fluorescence intensity at the interface as a function of time. PMID:21508474

  6. Electrophoretic transport equations - Electrophoretic models based on migration only and their interrelationships

    NASA Technical Reports Server (NTRS)

    Thormann, Wolfgang; Mosher, Richard A.

    1985-01-01

    The general equations which describe the electrophoretic transport of components in solution are restated using Newman's general concept of mobilities. A concise derivation of the moving boundary equation and the regulating function from the continuity equation is presented. Various other regulating principles across moving and stationary boundaries are also discussed, which permits a review of the features and interrelationships of the electrophoretic models based on electromigration only. The effect of considering an interactive (dissociating) solvent on the mathematical treatment is discussed.

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

    NASA Astrophysics Data System (ADS)

    Morrison, Dennis R.; Lewis, Marian L.; Barlow, Grant H.; Todd, Paul; Kunze, M. Elaine; Sarnoff, Burton E.; Li, Zhankui

    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.

  9. 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.

  10. 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.

  11. Assessment of DNA-binding affinity of cholinesterase reactivators and electrophoretic determination of their effect on topoisomerase I and II activity.

    PubMed

    Janockova, J; Zilecka, E; Kasparkova, J; Brabec, V; Soukup, O; Kuca, K; Kozurkova, M

    2016-08-16

    In this paper, we describe the biochemical properties and biological activity of a series of cholinesterase reactivators (symmetrical bisquaternary xylene-linked compounds, K106-K114) with ctDNA. The interaction of the studied derivatives with ctDNA was investigated using UV-Vis, fluorescence, CD and LD spectrometry, and electrophoretic and viscometric methods. The binding constants K were estimated to be in the range 1.05 × 10(5)-5.14 × 10(6) M(-1) and the percentage of hypochromism was found to be 10.64-19.28% (from UV-Vis titration). The used methods indicate that the studied samples are groove binders. Electrophoretic methods proved that the studied compounds clearly influence calf thymus Topo I (at 5 μM concentration, except for compounds K107, K111 and K114 which were effective at higher concentrations) and human Topo II (K110 partially inhibited Topo II effects even at 5 μM concentration) activity. PMID:27412811

  12. 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.

  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. Activity and electrophoretic profiles of liver aldehyde dehydrogenases from mice of inbred strains with different alcohol preference.

    PubMed

    Yamazaki, H; Nishiguchi, K; Miyamoto, R; Ogita, Z I; Nakanishi, S

    1983-01-01

    1. The activity of low Km-aldehyde dehydrogenase (ALDH) in the liver mitochondrial fraction (MT-fraction) from male C57BL/6J strain mice (alcohol preferring) was significantly higher than that from DBA/2 mice (alcohol avoiding). The F1 hybrids (C57BL/6J X DBA/2) did not exhibit the intermediate activity to these two strains. 2. Strain differences in liver mitochondrial ALDH isozymes were observed by isoelectric focusing. C57BL/6J strain had two isozymes at pH 7.1 while DBA/2 had no band at this pH. F1 hybrid mice had similar two bands with lower density to those of C57BL/6J at pH 7.1. There was no difference in zymograms of the soluble fraction between C57BL/6J and DBA/2 strains. 3. The present results suggest that the difference in alcohol preference of mice may depend on some restricted ALDH isozymes with different pl or electric mobility rather than the enzymatic activity in the liver MT-fraction. PMID:6822317

  16. 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

  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. PMID:25871116

  18. Purification of cereolysin and the electrophoretic separation of the active (reduced) and inactive (oxidized) forms of the purified toxin.

    PubMed Central

    Cowell, J L; Grushoff-Kosyk, P S; Bernheimer, A W

    1976-01-01

    Cereolysin was purified to apparent homogeneity by using ammonium sulfate fractionation, hydrophobic chromatography with AH-Sepharose, isoelectric focusing, and gel filtration. The active form of the toxin had an isoelectric point of 6.6, and the molecular weight of the protein was about 55,500 as judged by sodium dodecyl sulfate-gel electrophoresis, gel filtration, and gel electrophoresis using various concentrations of acrylamide. Cereolysin contained two half-cystine residues and was dependent on reducing agents, such as dithiothreitol, for maximal hemolytic activity and charge homogeneity. By using discontinuous acrylamide electrophoresis, two forms of the toxin could be observed: oxidized and reduced. If the toxin was purified in the absence of dithiothreitol, partial spontaneous oxidation resulted in the formation of an oxidized form of the toxin. Relative to the reduced form, the oxidized form moved slightly closer to the anode in gel electrophoresis at pH 9.0. If the toxin was purified in the presence of 5 mM dithiothreitol or if the spontaneously oxidized toxin was preincubated with dithiothreitol, only the reduced form of the protein was observed. When the logarithims of their relative mobilities were plotted against the concentration of acrylamide in the gels, the slopes for the reduced and oxidized forms were identical. This indicates that the two forms are identical in size and are separable because of different charges. The reduced protein could be inhibited by N-ethylmaleimide, 5,5'-dithiobis(2-nitrobenzoic acid), and p-hydroxymercuribenzoate. Inhibition by the latter two sulfhydryl reagents could be completely reversed by dithiothreitol. The reversibly oxidized form of the toxin did not appear to be inhibited by N-ethylmaleimide and apparently was either unable to bind to or had a decreased affinity for the erythrocyte membrane. Images PMID:820638

  19. 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

  20. On-line and Mobil Learning Activities

    NASA Astrophysics Data System (ADS)

    Ackerman, S. A.; Whittaker, T. M.; Jasmin, T.; Mooney, M. E.

    2012-12-01

    Introductory college-level science courses for non-majors are critical gateways to imparting not only discipline-specific information, but also the basics of the scientific method and how science influences society. They are also indispensable for student success to degree. On-line, web-based homework (whether on computers or mobile devices) is a rapidly growing use of the Internet and is becoming a major component of instruction in science, replacing delayed feedback from a few major exams. Web delivery and grading of traditional textbook-type questions is equally effective as having students write them out for hand grading, as measured by student performance on conceptual and problem solving exams. During this presentation we will demonstrate some of the interactive on-line activities used to teach concepts and how scientists approach problem solving, and how these activities have impacted student learning. Evaluation of the activities, including formative and summative, will be discussed and provide evidence that these interactive activities significantly enhance understanding of introductory meteorological concepts in a college-level science course. More advanced interactive activities are also used in our courses for department majors, some of these will be discussed and demonstrated. Bring your mobile devices to play along! Here is an example on teaching contouring: http://profhorn.aos.wisc.edu/wxwise/contour/index.html

  1. Sequence-specific nucleic acid mobility using a reversible block copolymer gel matrix and DNA amphiphiles (lipid-DNA) in capillary and microfluidic electrophoretic separations.

    PubMed

    Wagler, Patrick; Minero, Gabriel Antonio S; Tangen, Uwe; de Vries, Jan Willem; Prusty, Deepak; Kwak, Minseok; Herrmann, Andreas; McCaskill, John S

    2015-10-01

    Reversible noncovalent but sequence-dependent attachment of DNA to gels is shown to allow programmable mobility processing of DNA populations. The covalent attachment of DNA oligomers to polyacrylamide gels using acrydite-modified oligonucleotides has enabled sequence-specific mobility assays for DNA in gel electrophoresis: sequences binding to the immobilized DNA are delayed in their migration. Such a system has been used for example to construct complex DNA filters facilitating DNA computations. However, these gels are formed irreversibly and the choice of immobilized sequences is made once off during fabrication. In this work, we demonstrate the reversible self-assembly of gels combined with amphiphilic DNA molecules, which exhibit hydrophobic hydrocarbon chains attached to the nucleobase. This amphiphilic DNA, which we term lipid-DNA, is synthesized in advance and is blended into a block copolymer gel to induce sequence-dependent DNA retention during electrophoresis. Furthermore, we demonstrate and characterize the programmable mobility shift of matching DNA in such reversible gels both in thin films and microchannels using microelectrode arrays. Such sequence selective separation may be employed to select nucleic acid sequences of similar length from a mixture via local electronics, a basic functionality that can be employed in novel electronic chemical cell designs and other DNA information-processing systems. PMID:26095642

  2. Electrophoretic Transport of Biomolecules through Carbon Nanotube Membranes

    PubMed Central

    Sun, Xinghua; Su, Xin; Wu, Ji; Hinds, Bruce J.

    2013-01-01

    Electrophoretic transport of proteins across electrochemically oxidized multi-walled carbon nanotube (MWCNT) membranes has been investigated. Small charged protein, lysozyme, was successfully pumped across MWCNT membranes by electric field while rejecting larger bovine serum albumin (BSA). Transport of the lysozome was reduced by a factor of about 30 in comparison to bulk mobility and consistent with prediction for hindered transport. Mobilities between 0.33-1.4×10-9 m2/V-s were observed and are approximately 10 fold faster than comparable ordered nanoporous membranes and are consistent with continuum models. For mixtures of BSA and lysozyme, complete rejection of BSA is seen with electrophoretic separations PMID:21338104

  3. Designed and User-Generated Activity in the Mobile Age

    ERIC Educational Resources Information Center

    Kukulska-Hulme, Agnes; Traxler, John; Pettit, John

    2007-01-01

    The paper addresses the question of how to design for learning taking place on mobile and wireless devices. The authors argue that learning activity designers need to consider the characteristics of mobile learning; at the same time, it is vital to realise that learners are already creating mobile learning experiences for themselves. Profound…

  4. A novel electrophoretic technique designed to modify the ratio of magnesium isotopes inside the creatine kinase active sites. A preliminary report.

    PubMed

    Kouznetsov, Dmitri A; Arkhangelsky, Stanislav E; Berdieva, Alana G; Khasigov, Peter Z; Orlova, Marina A

    2004-09-01

    A simple and efficient preparative electrophoretic technique has been proposed to obtain a modified creatine kinase (CK, E.C.2.7.3.2) molecule with an increased content of 25Mg in the active site. A key point of the method is the special design of a 0.9 x 12.0 cm column for ascendent electrophoresis, packed consecutively, from the bottom to the top, with layers of 30 % PAAG (polyacrylamide grade), 25Mg2+ -containing 7.5 % PAAG, enzyme-binding ADP Sepharose and 2.2 % agarose gels, based on different tris-glycine and tris-HCl separation buffer systems. The isotope substitution process was a result of simultaneous desorption of enzyme from ADP Sepharose and electrically directed extensive flow of 25Mg2+ cations through the porous gel matrix. Greater than 8-fold 25Mg enrichment, i.e. a 10.2-86.3 % increase of 25Mg contribution to total enzyme magnesium, has been reached. The modified 25Mg-rich CK samples manifest higher (2.4-fold increase) values of specific catalytic activity when compared with intact (control) ones. PMID:15370286

  5. Convection Compensated Electrophoretic NMR

    NASA Astrophysics Data System (ADS)

    He, Qiuhong; Wei, Zhaohui

    2001-06-01

    A novel method of convection compensated ENMR (CC-ENMR) has been developed to detect electrophoretic motion of ionic species in the presence of bulk solution convection. This was accomplished using a gradient moment nulling technique to remove spectral artifacts from heat-induced convection and using the polarity switch of the applied electric field to retain spin phase modulations due to electrophoretic flow. Experiments were carried out with a mixture of 100 mM L-aspartic acid and 100 mM 4,9-dioxa-1,12-dodecanediamine to demonstrate this new method of ENMR. CC-ENMR enhances our previously developed capillary array ENMR (CA-ENMR) in solving the convection problem. The combined CA- and CC-ENMR approach strengthens the potential of multidimensional ENMR in simultaneous structural determination of coexisting proteins and protein conformations in biological buffer solutions of high ionic strength. Structural mapping of interacting proteins during biochemical reactions becomes possible in the future using ENMR techniques, which may have a profound impact on the understanding of biological events, including protein folding, genetic control, and signal transduction in general.

  6. Mobilization of evaporites in tectonically active terrains

    NASA Astrophysics Data System (ADS)

    Stiros, Stathis C.

    2015-04-01

    The role of evaporites, mostly halite, during seismic sequences is investigated using evidence from certain earthquakes with magnitude between approximately 6.0 and 7.2 which occurred in the last 60 years in the Zagros Mts. (Iran) and the Ionian Sea (Greece); i.e. two seismically active areas, characterized by evaporite-associated decollements and more shallow decollements combined with mature, along-thrusts intrusions. Studied earthquakes produced either large scale surface deformation, or were covered by high-resolution and accuracy GPS and INSAR data, permitting to fully recognize the deformation pattern. In all cases an "atypical", tectonic deformation pattern was observed, ranging from apparently "impossible" patterns (thrust and normal faults, sub-parallel and homothetic; 1953 Cephalonia earthquake, Greece) to rather diffuse tectonic patterns, even to "phantom" earthquakes (Zagros). Careful analysis and modeling of the surface deformation data, in combination with the available geological, geophysical and seismological data permits to recognize, and even to quantify differences between deformation observed, and that expected in ordinary environments. In particular, it was found that during earthquakes evaporites were mobilized, and this led either to a secondary deformation of the overburden, fully detached from the basement, or to significant aseismic (post-seismic) deformation. Anomalies in the distribution of seismic intensities due to evaporitic intrusions along faults were also observed. Apart from seismological implications (unpredictable post-seismic deformation, possibly also in the far-field), these results deriving from regions at different levels of evaporitic evolution, may prove useful to understand patterns of mobilization of evaporites during periods of tectonic activity.

  7. 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.

  8. 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...

  9. 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.

  10. 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

  11. Electrophoretic approach to the biochemical systematics of gammarids

    NASA Astrophysics Data System (ADS)

    Bulnheim, H.-P.; Scholl, A.

    1981-12-01

    By utilizing the techniques for electrophoretic separation of proteins by vertical starch gels, the biochemical systematics of 10 Gammaridae species obtained from marine, brackish and freshwater habitats was studied. They included Chaetogammarus marinus, Gammarus zaddachi, G. salinus, G. oceanicus, G. tigrinus, G. chevreuxi, G. locusta, G. duebeni duebeni, G. d. celticus, G. pulex pulex, and G. fossarum. For comparison of electrophoretic mobilities selected enzymes (phosphoglucose isomerase, glutamate oxalacetate transaminase, arginine phosphokinase, hexokinase, leucine amino peptidase, mannose 6-phosphate isomerase) were assayed. They were used as diagnostic characters in terms of electrophoretic identities or diversities of most frequent alleles at polymorphic gene loci. These criteria could be applied to estimate intrageneric enzymic variation and degrees of genetic relatedness between the crustacean amphipod species under consideration, thereby complementing traditional morphological classification.

  12. 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.

  13. Physical Activity Recognition with Mobile Phones: Challenges, Methods, and Applications

    NASA Astrophysics Data System (ADS)

    Yang, Jun; Lu, Hong; Liu, Zhigang; Boda, Péter Pál

    In this book chapter, we present a novel system that recognizes and records the physical activity of a person using a mobile phone. The sensor data is collected by built-in accelerometer sensor that measures the motion intensity of the device. The system recognizes five everyday activities in real-time, i.e., stationary, walking, running, bicycling, and in vehicle. We first introduce the sensor's data format, sensor calibration, signal projection, feature extraction, and selection methods. Then we have a detailed discussion and comparison of different choices of feature sets and classifiers. The design and implementation of one prototype system is presented along with resource and performance benchmark on Nokia N95 platform. Results show high recognition accuracies for distinguishing the five activities. The last part of the chapter introduces one demo application built on top of our system, physical activity diary, and a selection of potential applications in mobile wellness, mobile social sharing and contextual user interface domains.

  14. Early active mobilization following UCL repair With Mitek bone anchor.

    PubMed

    Crowley, Timothy P; Stevenson, Susan; Taghizadeh, Reika; Addison, Patrick; Milner, Richard H

    2013-09-01

    Ulnar collateral ligament (UCL) injuries of the thumb are common. Surgical repair is accepted as the treatment of choice for complete rupture of the ligament. Biomechanical studies have suggested that Mitek bone anchor repairs are potentially safe and strong enough to allow early controlled active mobilization. To date, there have been no studies to compare early active mobilization following Mitek bone anchor repair to standard postoperative rehabilitation involving thumb spica immobilization for the first 4 to 6 weeks. We performed a small pilot randomized control trial to assess the outcome of this new rehabilitation technique to that of standard immobilization following UCL repair with Mitek bone anchor. Our results show that on average early active mobilization leads to an earlier return to full hand function (6 vs. 8 wk) and an earlier return to work (7 vs. 11 wk). There is no difference in the final range of motion achieved. We suggest that Mitek bone anchor repairs for UCL ruptures are robust enough to allow early active mobilization and that a larger trial is warranted to assess whether early active mobilization is superior to standard rehabilitation. PMID:23970193

  15. Increasing physical activity through mobile device interventions: A systematic review.

    PubMed

    Muntaner, Adrià; Vidal-Conti, Josep; Palou, Pere

    2016-09-01

    Physical inactivity is a health problem that affects people worldwide and has been identified as the fourth largest risk factor for overall mortality (contributing to 6% of deaths globally). Many researchers have tried to increase physical activity levels through traditional methods without much success. Thus, many researchers are turning to mobile technology as an emerging method for changing health behaviours. This systematic review sought to summarise and update the existing scientific literature on increasing physical activity through mobile device interventions, taking into account the methodological quality of the studies. The articles were identified by searching the PubMed, SCOPUS and SPORTDiscus databases for studies published between January 2003 and December 2013. Studies investigating efforts to increase physical activity through mobile phone or even personal digital assistant interventions were included. The search results allowed the inclusion of 11 studies that gave rise to 12 publications. Six of the articles included in this review reported significant increases in physical activity levels. The number of studies using mobile devices for interventions has increased exponentially in the last few years, but future investigations with better methodological quality are needed to draw stronger conclusions regarding how to increase physical activity through mobile device interventions. PMID:25649783

  16. An electrophoretic study of urinary protein in the rat.

    PubMed

    SELLERS, A L; ROBERTS, S; RASK, I; SMITH, S; MARMORSTON, J; GOODMAN, H C

    1952-05-01

    The nature of the proteins present in the urine of the normal rat has been investigated by electrophoretic analysis and by fractional precipitation of these proteins by ammonium sulfate. Components similar to serum alpha- and beta-globulin constitute the major portion of the urinary protein in both male and female rats. Following the intraperitoneal injection of renin, a massive proteinuria occurs. The proteins excreted are similar in proportion and electric mobility to those of normal rat serum. PMID:14927799

  17. AN ELECTROPHORETIC STUDY OF URINARY PROTEIN IN THE RAT

    PubMed Central

    Sellers, Alvin L.; Roberts, Sidney; Rask, Irene; Smith, Stephen; Marmorston, Jessie; Goodman, Howard C.

    1952-01-01

    The nature of the proteins present in the urine of the normal rat has been investigated by electrophoretic analysis and by fractional precipitation of these proteins by ammonium sulfate. Components similar to serum α- and β-globulin constitute the major portion of the urinary protein in both male and female rats. Following the intraperitoneal injection of renin, a massive proteinuria occurs. The proteins excreted are similar in proportion and electric mobility to those of normal rat serum. PMID:14927799

  18. 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…

  19. 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.

  20. 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.

  1. 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.

  2. DESIGN AND CONSTRUCTION OF A MOBILE ACTIVATED CARBON REGENERATOR SYSTEM

    EPA Science Inventory

    Activated carbon adsorption has become a standard procedure for the cleanup of contaminated water streams. To facilitate such cleanup at hazardous waste and spill sites, mobile carbon adsorption units have been constructed and are now in use. Their primary drawback is the logisti...

  3. 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.

  4. [The NAS system: Nursing Activities Score in mobile technology].

    PubMed

    Catalan, Vanessa Menezes; Silveira, Denise Tolfo; Neutzling, Agnes Ludwig; Martinato, Luísa Helena Machado; Borges, Gilberto Cabral de Mello

    2011-12-01

    The objective of this study was to present the computerized structure that enables the use of the Nursing Activities Score (NAS) in mobile technology. It is a project for the development of technology production based on software engineering, founded on the theory of systems development life cycle. The NAS system was built in two modules: the search module, which is accessed using a personal computer (PC), and Data Collection module, which is accessed through a mobile device (Smartphone). The NAS system was constructed to allow other forms, in addition to the NAS tool, to be included in the future. Thus, it is understood that the development of the NAS will bring nurses closer to mobile technology and facilitate their accessibility to the data of the instrument relating to patients, thus assisting in decision-making and in staffing to provide nursing care. PMID:22241201

  5. 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

  6. 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

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

    PubMed

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

    2015-01-01

    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

  8. Ligand Mobility Modulates Immunological Synapse Formation and T Cell Activation

    PubMed Central

    Hsu, Chih-Jung; Hsieh, Wan-Ting; Waldman, Abraham; Clarke, Fiona; Huseby, Eric S.; Burkhardt, Janis K.; Baumgart, Tobias

    2012-01-01

    T cell receptor (TCR) engagement induces clustering and recruitment to the plasma membrane of many signaling molecules, including the protein tyrosine kinase zeta-chain associated protein of 70 kDa (ZAP70) and the adaptor SH2 domain-containing leukocyte protein of 76 kDa (SLP76). This molecular rearrangement results in formation of the immunological synapse (IS), a dynamic protein array that modulates T cell activation. The current study investigates the effects of apparent long-range ligand mobility on T cell signaling activity and IS formation. We formed stimulatory lipid bilayers on glass surfaces from binary lipid mixtures with varied composition, and characterized these surfaces with respect to diffusion coefficient and fluid connectivity. Stimulatory ligands coupled to these surfaces with similar density and orientation showed differences in their ability to activate T cells. On less mobile membranes, central supramolecular activation cluster (cSMAC) formation was delayed and the overall accumulation of CD3ζ at the IS was reduced. Analysis of signaling microcluster (MC) dynamics showed that ZAP70 MCs exhibited faster track velocity and longer trajectories as a function of increased ligand mobility, whereas movement of SLP76 MCs was relatively insensitive to this parameter. Actin retrograde flow was observed on all surfaces, but cell spreading and subsequent cytoskeletal contraction were more pronounced on mobile membranes. Finally, increased tyrosine phosphorylation and persistent elevation of intracellular Ca2+ were observed in cells stimulated on fluid membranes. These results point to ligand mobility as an important parameter in modulating T cell responses. PMID:22384241

  9. Electrophoretic separator for purifying biologicals

    NASA Technical Reports Server (NTRS)

    1975-01-01

    Mathematical expressions were developed to describe the interrelationships between operating requirements (capabilities), cell parameters, and system constraints in terms of design criteria definition. The mathematical model was programmed for computer solution. The model was exercised to identify performance-limiting characteristics, and analyses were conducted to predict operation in space of an experiment involving separation of four components. An engineering model of a flowing electrophoretic separator was constructed. The design is directed toward verifying improvements in resolution and throughput of a thicker cell than can be used on earth.

  10. 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.

  11. 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

  12. 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.

  13. 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

  14. 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.

  15. Energy-efficiency testing activities of the Mobile Energy Laboratory

    SciTech Connect

    Parker, G.B.

    1991-01-01

    This report summarizes energy-efficiency testing activities during the first and second quarters of fiscal year 1990 applying the Mobile Energy Laboratory (MEL) testing capabilities. Four MELs, developed by the US Department of Energy (DOE) Federal Energy Management Program (FEMP), are administered by Pacific Northwest Laboratory (PNL) for energy testing and program support functions at federal facilities. The using agencies principally fund MEL applications, while DOE/FEMP funds program administration and capability enhancement activities. This report fulfills the requirements established in 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.

  16. 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 Electrophoretic hemoglobin analysis system. (a) Identification. An electrophoretic hemoglobin analysis system is a device that electrophoretically separates and identifies normal and...

  17. 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...

  18. 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.

  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. Peptidase activities in Saccharomyces cerevisiae.

    PubMed Central

    Rose, B; Becker, J M; Naider, F

    1979-01-01

    At least four distinct aminopeptidase activities and a single dipeptidase activity were found in cell extracts of a leucine-lysine auxotroph of Saccharomyces cerevisiae. The assay for peptidase activity involved polyacrylamide gel electrophoresis followed by an enzyme-coupled activity staining procedure. The aminopeptidases had largely overlapping specificities but could be distinguished from one another by their electrophoretic mobilities and activities toward different peptide substrates. Substrates tested included both free and blocked di- and tripeptides and amino acid derivatives. Images PMID:378955

  1. Electrophoretic Migration of Branched DNA in Polymer Solutions

    NASA Astrophysics Data System (ADS)

    Lau, Henry; Archer, Lynden

    2009-03-01

    The electrophoretic migration of large, star-branched DNA molecules has previously been studied in both neutral polymer solutions and gels, and the results have provided insight into the local interactions between the analytes and the sieving matrix during electrophoresis (Electrophoresis, 2006, 27, 3128). This talk focuses on using rigid-rod DNA molecules of complex shapes as model analytes in studying the effects of analyte architecture on mobility in polymer solutions. Electrophoresis of a series of Y-shaped DNA molecules that mimick the shapes of antibodies, was performed in polymer solutions above the overlap concentration and at electric fields up to 300V/cm. The location of the branch point as well as the arm sizes are varied in order to examine their influence on mobility. Our results point to novel, topology-based fractionation strategies for separating biological molecules using capillary electrophoresis with polymer sieving media.

  2. 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,…

  3. 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

  4. Cell electrophoretic characterization of peripheral blood lymphocyte subpopulations enriched by rosette formation, from normal individuals and CLL patients.

    PubMed

    Rychly, J; Babusíková, O; Koníková, E; Anders, O

    1984-01-01

    Peripheral blood lymphocytes from healthy subjects and patients with chronic lymphatic leukemia (CLL) were isolated and their subpopulations enriched through formation of spontaneous rosettes with sheep or mouse red blood cells, respectively. Electrophoretic measurements were performed in unseparated as well as in fractionated cell populations. Normal blood lymphocytes showed two clearly distinguishable populations of different electrophoretic mobilities. After separation by SRBC rosette formation the rosette-forming cells could be identified as high mobility cells. CLL lymphocytes showed in most cases an unimodally distributed cytopherogram, the mean electrophoretic mobility being intermediate between the low and high mobility cells of control persons. After separation through mouse erythrocytes rosette formation these cells contained two cell fractions differing in their electrophoretic mobility: a fraction of slower mouse rosette-forming cells and a fraction of the non-MRFC which contained mainly cells of higher mobility that could be identified as enriched T cells. These both fractions showed unimodal distributions. This study shows that CLL lymphocyte subpopulations can be further characterized by surface charge density. PMID:6700796

  5. 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. PMID:25582166

  6. Evidence for segmental mobility in the active site of pepsin

    SciTech Connect

    Pohl, J.; Strop, P.; Senn, H.; Foundling, S.; Kostka, V.

    1986-05-01

    The low hydrolytic activity (k/sub cat/ < 0.001 s/sup -1/) of chicken pepsin (CP) towards tri- and tetrapeptides is enhanced at least 100 times by modification of its single sulfhydryl group of Cys-115, with little effect on K/sub m/-values. Modification thus simulates the effect of secondary substrate binding on pepsin catalysis. The rate of Cys-115 modification is substantially decreased in the presence of some competitive inhibitors, suggesting its active site location. Experiments with CP alkylated at Cys-115 with Acrylodan as a fluorescent probe or with N-iodoacetyl-(4-fluoro)-aniline as a /sup 19/F-nmr probe suggest conformation change around Cys-115 to occur on substrate or substrate analog binding. The difference /sup 1/H-nmr spectra (500 MHz) of unmodified free and inhibitor-complexed CP reveal chemical shifts almost exclusively in the aromatic region. The effects of Cu/sup + +/ on /sup 19/F- and /sup 1/H-nmr spectra have been studied. Examination of a computer graphics model of CP based on E. parasitica pepsin-inhibitor complex X-ray coordinates suggests that Cys-115 is located near the S/sub 3//S/sub 5/ binding site. The results are interpreted in favor of segmental mobility of this region important for pepsin substrate binding and catalysis.

  7. Adaptive activity and environment recognition for mobile phones.

    PubMed

    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

  8. 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

  9. 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

  10. Electrophoretic characterization of insulin growth factor (IGF-1) functionalized magnetic nanoparticles.

    PubMed

    Viota, Julián L; Rudzka, Katarzyna; Trueba, Ángel; Torres-Aleman, Ignacio; Delgado, Ángel V

    2011-05-17

    The synthesis of composite nanoparticles consisting of a magnetite core coated with a layer of the hormone insulin growth factor 1 (IGF-1) is described. The adsorption of the hormone in the different formulations is first studied by electrophoretic mobility measurements as a function of pH, ionic strength, and time. Because of the permeable character expected for both citrate and IGF-1 coatings surrounding the magnetite cores, an appropriate analysis of their electrophoretic mobility must be addressed. Recent developments of electrokinetic theories for particles covered by soft surface layers have rendered possible the evaluation of the softness degree from raw electrophoretic mobility data. In the present contribution, the data are quantitatively analyzed based on the theoretical model of the electrokinetics of soft particles. As a result, information is obtained on both the thickness and the charge density of the surrounding layer. It is shown that IGF-1 adsorbs onto the surface of citrate-coated magnetite nanoparticles, and adsorption is confirmed by dot-blot analysis. In addition, it is also demonstrated that the external layer of IGF-1 exerts a shielding effect on the surface charge of citrate-magnetite particles, as suggested by the mobility reduction upon contacting the particles with the hormone. Aging effects are demonstrated, providing an electrokinetic fingerprint of changes in adsorbed protein configuration with time. PMID:21506536

  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. 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...

  15. 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...

  16. 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.

  17. 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.

  18. Simulations of electrophoretic collisions of DNA knots with gel obstacles

    NASA Astrophysics Data System (ADS)

    Weber, C.; DeLos Rios, P.; Dietler, G.; Stasiak, A.

    2006-04-01

    Gel electrophoresis can be used to separate nicked circular DNA molecules of equal length but forming different knot types. At low electric fields, complex knots drift faster than simpler knots. However, at high electric field the opposite is the case and simpler knots migrate faster than more complex knots. Using Monte Carlo simulations we investigate the reasons of this reversal of relative order of electrophoretic mobility of DNA molecules forming different knot types. We observe that at high electric fields the simulated knotted molecules tend to hang over the gel fibres and require passing over a substantial energy barrier to slip over the impeding gel fibre. At low electric field the interactions of drifting molecules with the gel fibres are weak and there are no significant energy barriers that oppose the detachment of knotted molecules from transverse gel fibres.

  19. 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.

  20. 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.

  1. 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…

  2. 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.…

  3. 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.…

  4. 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…

  5. 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…

  6. Mobile phone usage in complex urban systems: a space-time, aggregated human activity study

    NASA Astrophysics Data System (ADS)

    Tranos, Emmanouil; Nijkamp, Peter

    2015-04-01

    The present study aims to demonstrate the importance of digital data for investigating space-time dynamics of aggregated human activity in urban systems. Such dynamics can be monitored and modelled using data from mobile phone operators regarding mobile telephone usage. Using such an extensive dataset from the city of Amsterdam, this paper introduces space-time explanatory models of aggregated human activity patterns. Various modelling experiments and results are presented, which demonstrate that mobile telephone data are a good proxy of the space-time dynamics of aggregated human activity in the city.

  7. 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…

  8. Mobile satellite communications technology - A summary of NASA activities

    NASA Technical Reports Server (NTRS)

    Dutzi, E. J.; Knouse, G. H.

    1986-01-01

    Studies in recent years indicate that future high-capacity mobile satellite systems are viable only if certain high-risk enabling technologies are developed. Accordingly, NASA has structured an advanced technology development program aimed at efficient utilization of orbit, spectrum, and power. Over the last two years, studies have concentrated on developing concepts and identifying cost drivers and other issues associated with the major technical areas of emphasis: vehicle antennas, speech compression, bandwidth-efficient digital modems, network architecture, mobile satellite channel characterization, and selected space segment technology. The program is now entering the next phase - breadboarding, development, and field experimentation.

  9. 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.

  10. Mobility systems activity for lunar rovers at MSFC

    NASA Technical Reports Server (NTRS)

    Jones, C. S., Jr.; Nola, F. J.

    1971-01-01

    The Apollo Lunar Roving Vehicle (LRV) mobility system is described. Special emphasis is given to the redundancy aspects and to the selection of the drive motors. A summary chart of the performance on the lunar surface during the Apollo 15 flight is included. An appendix gives details on some development work on high efficiency drive systems and compares these systems to the selected system.

  11. 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.

  12. 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. PMID:26152855

  13. New reflective-type electrophoretic display

    NASA Astrophysics Data System (ADS)

    Orsaev, A. M.; Orsaev, T. M.; Gaev, D. S.

    2001-06-01

    Advantages and problems of the electrophoretic display design are considered. To increase its lifetime a new EPD version is proposed, and operation process is described. Main distinguish feature is the present of an agile film as the third electrode. Such a display can be manufactured on the base of standard technological processes and promises to be X-Y multiplex addressed, simple and cheap for manufacturing.

  14. A unified mathematical theory of electrophoretic processes

    NASA Technical Reports Server (NTRS)

    Bier, M.; Palusinski, O. A.; Mosher, R. A.; Graham, A.; Saville, D. A.

    1983-01-01

    A mathematical theory is presented which shows that each of the four classical electrophoretic modes (zone electrophoresis, moving boundary electrophoresis, isotachophoresis, and isoelectric focusing) is based on the same general principles and can collectively be described in terms of a single set of equations. This model can predict the evolution of the four electrophoretic modes as a function of time. The model system is one-dimensional, neglecting the effects of electroosmosis, temperature gradients, and any bulk flows of liquid. The model is based on equations which express the components' dissociation equilibria, the mass transport due to electromigration and diffusion, electroneutrality, and the conservation of mass and charge. The model consists of a system of coupled partial differential and nonlinear algebraic equations which can be solved numerically by use of a computer. The versatility of this model was verified using an example of a three-component system containing cacodylate, tris hydroxylmethylaminomethane, and histidine. Results show that this model not only correctly predicts the characteristic features of each electrophoretic mode, but also gives details of the concentration, pH, and conductivity profiles not easily amenable to direct experimental measurement.

  15. 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.

  16. 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

  17. Luminescent electrophoretic particles via miniemulsion polymerization for night-vision electrophoretic displays.

    PubMed

    Meng, Xianwei; Wen, Ting; Qiang, Li; Ren, Jun; Tang, Fangqiong

    2013-05-01

    A novel glowing electrophoretic display (EPD) is achieved by luminescent electrophoretic particles (EPs), which is potentially to improve the situation in which the existing EPDs disable in darkness. To combine both modes of reflective and emissive displays, a trilayer luminescence EP is designed and synthesized via an improved miniemulsion polymerization. The luminescence EP is composed of a pigment core, a polystyrene interlayer, and a fluorescent coating. The particle sizes are from 140 to 170 nm, and the size distribution is narrow. Their ζ potential value is -12.4 mV, which is enough to migrate in the electrophoretic fluid by the driving of an electric field. The display performance of the particles in an EPD cell has been characterized under the bias of 20 V. Both the reflectance (491 nm) and fluorescence (521 nm) intensities of the EPD cell remained in a constant range after 30 switches. PMID:23547950

  18. Parental physical activity, safety perceptions and children’s independent mobility

    PubMed Central

    2013-01-01

    Background Parents are likely to be a basic influence on their children's behavior. There is an absence of information about the associations between parents' physical activity and perception of neighborhood environment with children’s independent mobility. The purpose of this study is to examine the contribution of parental physical activity and perception of neighborhood safety to children’s independent mobility. Methods In this cross-sectional study of 354 pupils and their parents, independent mobility, perceptions of neighborhood safety and physical activity were evaluated by questionnaire. Categorical principal components analyses were used to determine the underlying dimensions of both independent mobility and perceptions of neighborhood safety items. Results The strongest predictor of independent mobility was the parental perception of sidewalk and street safety (ß = 0.132). Parent’s physical activity was also a significant predictor. The final model accounted for 13.0% of the variance. Conclusions Parental perception of neighborhood safety and parents’ self reported physical activity might be associated with children’s independent mobility. Further research in this topic is needed to explore this possible association. PMID:23767778

  19. 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

  20. Preparation and surface encapsulation of hollow TiO nanoparticles for electrophoretic displays

    NASA Astrophysics Data System (ADS)

    Zhao, Qian; Tan, Tingfeng; Qi, Peng; Wang, Shirong; Bian, Shuguang; Li, Xianggao; An, Yong; Liu, Zhaojun

    2011-02-01

    Hollow black TiO nanosparticles were obtained via deposition of inorganic coating on the surface of hollow core-shell polymer latex with Ti(OBu)4 as precursor and subsequent calcination in ammonia gas. Hollow TiO particles were characterized by scanning electron microscope, transmission electronic microscopy, X-ray diffraction, and thermogravimetric analysis. Encapsulation of TiO via dispersion polymerization was promoved by pretreating the pigments with 3-(trimethoxysilyl) propyl methacrylate, making it possible to prepare hollow TiO-polymer particles. When St and DVB were used as polymerization monomer, hollow TiO-polymer core-shell particles came into being via dispersion polymerization, and the lipophilic degree is 28.57%. Glutin-arabic gum microcapsules containing TiO-polymer particles electrophoretic liquid were prepared using via complex coacervation. It was founded that hollow TiO-polymer particles had enough electrophoretic mobility after coating with polymer.

  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. Can directed activity improve mobility in Huntington's disease?

    PubMed

    Busse, M E; Rosser, A E

    2007-04-30

    Huntington's disease is an inherited disorder of the CNS that results in progressive deterioration of mobility and cognition and also affects behaviour. There are no disease-modifying interventions available to date, although there has been considerable progress in research directed at understanding the pathological basis of the disease with a view to identifying potential treatments. It is however important not to overlook currently available treatment strategies, including rehabilitation approaches. There has been little work to date to explore the potential of such approaches and here we highlight the need for more systematic studies in this area as well as the need for good objective assessment tools and the potential role that rehabilitation and training may have in the application of novel treatment options. PMID:17352942

  3. Improvements in in-plane electrophoretic displays

    NASA Astrophysics Data System (ADS)

    Henzen, Alex

    2011-03-01

    Electronic paper is now developing fast into an accepted alternative for paper. Its applications nowadays seem focused on books, documents and newspapers. Development of credible color implementations of electrophoretic displays has been initiated, focusing on multi-layer in-plane electrophoresis, but the difficulties associated with these systems (particle drift, aperture, accuracy) were so far not solved. Electro-osmotic principles lead to openings towards multi-layer color displays as well as fast switching, high reflectance grayscale displays. Drift, aperture and accuracy can be brought to the level necessary to create in-plane switching electro-osmotic displays without the need for encapsulation

  4. 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.

  5. 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…

  6. 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...

  7. 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…

  8. 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...

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

    NASA Astrophysics Data System (ADS)

    Azarbar, Bahman

    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.

  10. 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.

  11. 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.

  12. 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

  13. 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. PMID:27148889

  14. 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.

  15. Preparation and properties of red inorganic hollow nanospheres for electrophoretic display

    NASA Astrophysics Data System (ADS)

    Fang, Yi; Wang, Shirong; Xiao, Yin; Li, Xianggao

    2014-10-01

    An effective approach had been developed for the preparation of Fe-doped TiO2 red hollow nanospheres via template method using PMMA-BA copolymers as the core template by a two-step hydrolysis process. The nanospheres were rarely displayed fragmentation and exhibited hollow structures with uniform size and shape. Then, the multicomponent Fe/Co/Al-doped TiO2 hollow nanospheres were produced with Co and Al as tinting metal ions so as to endow them with higher color saturation and brightness. The average diameter of the hollow spheres coated with a layer of α-Fe2O3 was approximately 300 nm and the thickness of the layer was roughly 50 nm. The electrophoretic mobility and zeta potential of two kinds of hollow particles were about -1.0 × 10-5 cm2 v-1 s-1 and -100 mV, respectively. Finally, the electrophoretic inks prototype device was successfully assembled using dispersion of the obtained red hollow nanospheres in a mixed dielectric solvent with TiO2 white particles as contrast. Under an applied bias voltage of 30 V, the response time of the simple EPD device was 1121 ms and the max contrast was 3.173, which had shown great potential for practical application in a vivid chromatic electrophoretic display.

  16. Electrophoretically induced aqueous flow through single-wall carbon nanotube membranes

    PubMed Central

    Wu, Ji; Gerstandt, Karen; Zhang, Hongbo; Liu, Jie; Hinds, Bruce. J.

    2013-01-01

    Electrophoresis, the motion of charged species through liquids and pores under an external electric field, has been principle source of chemical pumping for numerous micro- and nano-fluidic devices platforms. Recent studies of ion current through single or few carbon nanotube channels range from near bulk mobility to 2-7 orders of magnitude of enhancement but cannot directly measure ion flux. Membranes, with large number of nanotube pores, allow independent confirmation of ion current and flux. Here we report that the aqueous electrophoretic mobility of ions within the graphitic cores of carbon nanotube membranes, with a uniform pore size of 0.9 ± 0.2 nm, is enhanced ∼3 times that of bulk mobilities. The induced electroosmotic velocities are 4 orders of magnitude faster than those measured in conventional porous materials. We also show that a nanotube membrane can function as a rectifying diode due to ionic steric effects within tightly controlled nanotube diameter. PMID:22245860

  17. 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…

  18. 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

  19. 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).

  20. Human blood platelet membrane glycoproteins. Resolution in different polyacrylamide gel electrophoretic systems.

    PubMed

    Jenkins, C S; Ali-Briggs, E F; Zonneveld, G T; Sturk, A; Clemetson, K J

    1980-02-29

    The separation of the major platelet membrane glycoproteins of normal subjects and subjects with well defined platelet membrane glycoprotein abnormalities have been examined using four different polyacrylamide gel electrophoretic techniques (continuous and discontinuous). The mobilities of the resolved glycoprotein bands have been correlated with the glycoprotein nomenclature proposed for the conventional sodium dodecyl sulphate-phosphate buffer system. Since the glycoprotein distribution varies depending on the system used, the merits of each method should be considered before application to a specific problem. PMID:6768152

  1. 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.

  2. 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.

  3. 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

  4. 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

  5. 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

  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. Electrophoretic behavior of DNA-methyl-CpG-binding domain protein complexes revealed by capillary electrophoreses laser-induced fluorescence.

    PubMed

    Zhong, Shangwei; Zou, Dandan; Zhao, Bailin; Zhang, Dapeng; Li, Xiangjun; Wang, Hailin

    2015-12-01

    The free solution electrophoretic behavior of DNA-protein complexes depends on their charge and mass in a certain experimental condition, which are two fundamental properties of DNA-protein complexes in free solution. Here, we used CE LIF to study the free solution behavior of DNA-methyl-CpG-binding domain protein (MBD2b) complexes through exploring the relationship between the mobilities, charge, and mass of DNA-protein complexes. This method is based on the effective separation of free DNA and DNA-protein complexes because of their different electrophoretic mobility in a certain electric field. In order to avoid protein adsorption, a polyacrylamide-coated capillary was used. Based on the evaluation of the electrophoretic behavior of formed DNA-MBD2b complexes, we found that the values of (μ0 /μ)-1 were directly proportional to the charge-to-mass ratios of formed complexes, where the μ0 and μ are the mobility of free DNA probe and DNA-protein complex, respectively. The models were further validated by the complex mobilities of protein with various lengths of DNA probes. The deviation of experimental and calculated charge-to-mass ratios of formed complexes from the theoretical data was less than 10%, suggesting that our models are useful to analyze the DNA-binding properties of the purified MBD2b protein and help to analyze other DNA-protein complexes. Additionally, this study enhances the understanding of the influence of the charge-to-mass ratios of formed DNA-protein complexes on their separation and electrophoretic behaviors. PMID:26377303

  8. 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,…

  9. An Active K/K-Band Antenna Array for the NASA ACTS Mobile Terminal

    NASA Technical Reports Server (NTRS)

    Tulintseff, A.; Crist, R.; Densmore, A.; Sukamto, L.

    1993-01-01

    An active K/K-band antenna array is currently under development for NASA's ACTS Mobile Terminal (AMT). The AMT task will demonstrate voice, data, and video communications to and from the AMT vehicle in Los Angeles, California, and a base station in Cleveland, Ohio, via the ACTS satellite at 30 and 20 GHz.

  10. 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…

  11. Pedagogical Values of Mobile-Assisted Task-Based Activities to Enhance Speaking Skill

    ERIC Educational Resources Information Center

    Mohammadi, Mojtaba; Safdari, Nastaran

    2015-01-01

    The purpose of the present study was to examine the impact of online mobile-assisted task-based activities on improving Iranian intermediate English as a Foreign Language (EFL) learners' speaking skills. To achieve the purpose of the study, 90 intermediate language learners were selected ranging between 13 to 16 years old and divided into three…

  12. Explaining the mobility of retinal in activated rhodopsin and opsin.

    PubMed

    Mertz, Blake; Feng, Jun; Corcoran, Conor; Neeley, Brandon

    2015-11-01

    Rhodopsin, the mammalian dim light photoreceptor, is the canonical model for G protein-coupled receptors. Activation of rhodopsin occurs when the covalently bound inverse agonist, retinal, absorbs a photon and undergoes an 11-cis to all-trans isomerization. Two critical components of the visual cycle occur with the (1) hydrolytic release of all-trans retinaldehyde and subsequent (2) uptake of 11-cis retinaldehyde to reform the Schiff base linkage in the apoprotein opsin. Two pores on the surface of opsin are connected via the retinal channel, as discovered upon solution of the X-ray crystal structure (Park et al., Nature, 2008), and could serve as potential entryways for uptake and release. Using molecular dynamics simulations, we examined the behavior of rhodopsin in the Meta-II conformation (active) under Meta-I conditions (inactive), and discovered that the retinal binding pocket is flexible enough to allow a 180° rotation along the long axis of the retinal polyene chain. This result reconciles a discrepancy between the known polyene chain orientation from crystallographic and spectroscopic studies and opens the door for further investigation into the intermolecular interactions between the retinal ligand and the apoprotein opsin. Subsequent docking studies of both isomers of retinal into the opsin channel were then conducted to identify the mechanism for uptake and release. Our results suggest that retinal undergoes unidirectional uptake through Pore A and release through Pore B, and that aromatic sidechain interactions play a key role in stabilizing retinal within the opsin channel. These findings are significant in developing our understanding of the retinoid cycle and how ligand-receptor interactions in rhodopsin relate to G protein-coupled receptor activation. PMID:26248892

  13. 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

  14. Mobile Phone Interventions to Increase Physical Activity and Reduce Weight

    PubMed Central

    Stephens, Janna; Allen, Jerilyn

    2013-01-01

    Objective This systematic review was conducted to determine user satisfaction and effectiveness of smartphone applications and text messaging interventions to promote weight reduction and physical activity. Methods Studies of smartphone applications and text messaging interventions related to the cardiovascular risk factors of physical inactivity and overweight/obesity published between January 2005 and August 2010 were eligible. Studies related to disease management were excluded. Study characteristics and results were gathered and synthesized. Results A total of 36 citations from CINAHL, EMBASE, MEDLINE, PsyclNFO, and PubMed were identified; 7 articles were eligible for inclusion. The most frequent outcome measured in the studies was change in the weight of participants (57%). More than half of the studies (71%) reported statistically significant results in at least 1 outcome of weight loss, physical activity, dietary intake, decreased body mass index, decreased waist circumference, sugar-sweetened beverage intake, screen time, and satisfaction or acceptability outcomes. Conclusions All of the technology interventions that were supported by education or an additional intervention demonstrated a beneficial impact of text messaging or smartphone application for reduction of physical inactivity and/or overweight/obesity. More rigorous trials that determine what parts of the technology or intervention are effective as well as establishment of cost-effectiveness are necessary for further evaluation of smartphone and text messaging interventions. PMID:22635061

  15. The mPED randomized controlled clinical trial: applying mobile persuasive technologies to increase physical activity in sedentary women protocol

    PubMed Central

    2011-01-01

    Background Despite the significant health benefits of regular physical activity, approximately half of American adults, particularly women and minorities, do not meet the current physical activity recommendations. Mobile phone technologies are readily available, easily accessible and may provide a potentially powerful tool for delivering physical activity interventions. However, we need to understand how to effectively apply these mobile technologies to increase and maintain physical activity in physically inactive women. The purpose of this paper is to describe the study design and protocol of the mPED (mobile phone based physical activity education) randomized controlled clinical trial that examines the efficacy of a 3-month mobile phone and pedometer based physical activity intervention and compares two different 6-month maintenance interventions. Methods A randomized controlled trial (RCT) with three arms; 1) PLUS (3-month mobile phone and pedometer based physical activity intervention and 6-month mobile phone diary maintenance intervention), 2) REGULAR (3-month mobile phone and pedometer based physical activity intervention and 6-month pedometer maintenance intervention), and 3) CONTROL (pedometer only, but no intervention will be conducted). A total of 192 physically inactive women who meet all inclusion criteria and successfully complete a 3-week run-in will be randomized into one of the three groups. The mobile phone serves as a means of delivering the physical activity intervention, setting individualized weekly physical activity goals, and providing self-monitoring (activity diary), immediate feedback and social support. The mobile phone also functions as a tool for communication and real-time data capture. The primary outcome is objectively measured physical activity. Discussion If efficacy of the intervention with a mobile phone is demonstrated, the results of this RCT will be able to provide new insights for current behavioral sciences and m

  16. 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

  17. 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

  18. 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

  19. 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.

  20. 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.

  1. Effects of structural properties of the Stern layer on the electrophoretic migration of a highly charged spherical macroion.

    PubMed

    Rezaei, Majid; Azimian, Ahmad Reza

    2015-12-01

    The electrophoretic migration of a highly charged spherical macroion suspended in an aqueous solution of NaCl is studied using the molecular dynamic method. The objective is to examine the effects of the colloidal surface charge density on the electrophoretic mobility (μ) of the spherical macroion. The bare charge and the size of the macroion are varied separately to induce changes in the colloidal surface charge density. Our results indicate that μ depends on colloidal surface charge density in a nonmonotonic manner, but that this relationship is independent of the way the surface charge density is varied. It is found that an increase in colloidal surface charge density may lead to the formation of new sublayers in the Stern layer. The μ profile is also found to have a local maximum for a bare charge at which a new sublayer is formed in the Stern layer, and a local minimum for a bare charge at which the outer sublayer becomes relatively dense. Finally, the electrophoretic flow caused by the migration of the spherical macroion is studied to find that one decisive factor causing the electrophoretic flow is the ability of the macroion to carry anions in the electrolyte solution. PMID:26456026

  2. Mobility disability and the pattern of accelerometer-derived sedentary and physical activity behaviors in people with multiple sclerosis

    PubMed Central

    Ezeugwu, Victor; Klaren, Rachel E.; A. Hubbard, Elizabeth; Manns, Patricia (Trish); Motl, Robert W.

    2015-01-01

    Objective Low physical activity and high sedentary behavior levels are major concerns in persons with multiple sclerosis (MS) and these differ depending on the level of mobility disability. However, the manner in which daily activity is accumulated is currently unknown in this population. Methods A secondary analysis was performed on a combined data set of persons with MS from two previous investigations of physical activity and symptomatic or quality of life outcomes in the United States over a two year period (2007–2009). Mobility disability status was determined using the Patient Determined Disease Steps (PDDS) while activity behavior was objectively monitored using an ActiGraph accelerometer for 7 days. Results Persons with MS who have mobility disability were involved in sedentary behavior, light and moderate intensity activity for 65%, 34% and 1% of the day, respectively compared to 60%, 37%, and 3%, respectively in those without mobility disability (p < 0.05). Breaks in sedentary time did not differ by mobility disability status. Compared to those without mobility disability, the average number of sedentary bouts longer than 30 min was greater in those with mobility disability (p = 0.016). Conclusion Persons with MS with mobility disability are less active, engage in more sedentary behavior and accumulate prolonged sedentary bouts. PMID:26844077

  3. MICROSPORIDIAN TAXONOMY: APPLICATION OF ELECTROPHORETIC AND IMMUNOLOGICAL TECHNIQUES

    EPA Science Inventory

    A review of investigations utilizing electrophoretic and immunological methods for identification and classification of microsporidians, the group to which the first protozoan microbial pesticide belongs, indicate that these methods can be successfully used to classify strains an...

  4. 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.

  5. 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.

  6. 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.

  7. A lateral electrophoretic flow diagnostic assay

    PubMed Central

    Lin, Robert; Skandarajah, Arunan; Gerver, Rachel E.; Neira, Hector D.; Fletcher, Daniel A.

    2015-01-01

    Immunochromatographic assays are a cornerstone tool in disease screening. To complement existing lateral flow assays (based on wicking flow) we introduce a lateral flow format that employs directed electrophoretic transport. The format is termed a “lateral e-flow assay” and is designed to support multiplexed detection using immobilized reaction volumes of capture antigen. To fabricate the lateral e-flow device, we employ mask-based UV photopatterning to selectively immobilize unmodified capture antigen along the microchannel in a barcode-like pattern. The channel-filling polyacrylamide hydrogel incorporates a photoactive moiety (benzophenone) to immobilize capture antigen to the hydrogel without a priori antigen modification. We report a heterogeneous sandwich assay using low-power electrophoresis to drive biospecimen through the capture antigen barcode. Fluorescence barcode readout is collected via a low-resource appropriate imaging system (CellScope). We characterize lateral e-flow assay performance and demonstrate a serum assay for antibodies to the hepatitis C virus (HCV). In a pilot study, the lateral e-flow assay positively identifies HCV+ human sera in 60 min. The lateral e-flow assay provides a flexible format for conducting multiplexed immunoassays relevant to confirmatory diagnosis in near-patient settings. PMID:25608872

  8. 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

  9. Activity Classification Using Mobile Phone based Motion Sensing and Distributed Computing.

    PubMed

    Artetxe, Arkaitz; Beristain, Andoni; Kabongo, Luis

    2014-01-01

    In this work we present a system that uses the accelerometer embedded in a mobile phone to perform activity recognition, with the purpose of continuously and pervasively monitoring the users' level of physical activity in their everyday life. Several classification algorithms are analysed and their performance measured, based for 6 different activities, namely walking, running, climbing stairs, descending stairs, sitting and standing. Feature selection has also been explored in order to minimize computational load, which is one of the main concerns given the restrictions of smartphones in terms of processor capabilities and specially battery life. PMID:25488205

  10. 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

  11. An active K/Ka-band antenna array for the NASA ACTS mobile terminal

    NASA Technical Reports Server (NTRS)

    Tulintseff, A.; Crist, R.; Densmore, Art; Sukamto, L.

    1993-01-01

    An active K/Ka-band antenna array is currently under development for NASA's ACTS Mobile Terminal (AMT). The AMT task will demonstrate voice, data, and video communications to and from the AMT vehicle in Los Angeles, California, and a base station in Cleveland, Ohio, via the ACTS satellite at 30 and 20 GHz. Satellite tracking for the land-mobile vehicular antenna system involves 'mechanical dithering' of the antenna, where the antenna radiates a fixed beam 46 deg. above the horizon. The antenna is to transmit horizontal polarization and receive vertical polarization at 29.634 plus or minus 0.15 GHz and 19.914 plus or minus 0.15 GHz, respectively. The active array will provide a minimum of 22 dBW EIRP transmit power density and a -8 dB/K deg. receive sensitivity.

  12. Off-the-shelf mobile handset environments for deploying accelerometer based gait and activity analysis algorithms.

    PubMed

    Hynes, Martin; Wang, Han; Kilmartin, Liam

    2009-01-01

    Over the last decade, there has been substantial research interest in the application of accelerometry data for many forms of automated gait and activity analysis algorithms. This paper introduces a summary of new "of-the-shelf" mobile phone handset platforms containing embedded accelerometers which support the development of custom software to implement real time analysis of the accelerometer data. An overview of the main software programming environments which support the development of such software, including Java ME based JSR 256 API, C++ based Motion Sensor API and the Python based "aXYZ" module, is provided. Finally, a sample application is introduced and its performance evaluated in order to illustrate how a standard mobile phone can be used to detect gait activity using such a non-intrusive and easily accepted sensing platform. PMID:19964383

  13. Association of electrophoretic karyotype of Candida stellatoidea with virulence for mice

    SciTech Connect

    Kwon-Chung, K.J.; Wickes, B.L.; Merz, W.G.

    1988-07-01

    Seven isolates of Candida stellatoidea were studied for their electrophoretic karyotype, virulence for mice, sensitivity to UV radiation, growth rate in vitro, reaction on cycloheximide-indicator medium, and proteinase activity. The isolates exhibited one of two distinct electrophoretic karyotypes as determined by orthogonal field alternating gel electrophoresis (OFAGE). Four isolates, including the type culture of C. stellatoidea, belonged to electrophoretic karyotype type I by OFAGE, showing eight to nine bands of which at least two bands were less than 1,000 kilobases in size as estimated by comparison with the DNA bands of Saccharomyces cerevisiae. These isolates failed to produce fatal infection in mice within 20 days when 5 X 10(5) cells were injected intravenously. The yeasts were cleared from the kidneys of two of three mice tested by day 30. Type I showed proteinase activity on bovine serum albumin agar at pH 3.8 and produced a negative reaction on cycloheximide-bromcresol green medium within 48 h. The three grouped in type II by OFAGE showed banding patterns similar to those of a well-characterized isolate of Candida albicans. The isolates of type II had an electrophoretic karyotype of six to seven bands approximately 1,200 kilobases or greater in size. All three type II isolates were highly virulent for mice, producing fatality curves similar to those of a previously studied C. albicans isolate. From 80 to 90% of the mice injected with 5 X 10(5) cells intravenously died within 20 days. The type II isolates produced a positive reaction on cycloheximide-bromcresol green agar and showed no proteinase activity on bovine serum albumin agar at the low pH. In addition, the type II isolates grew faster and were significantly more resistant to UV irradiation than the type I isolates.

  14. A mobile system for the multifrequency Doppler sounding of the modified ionosphere in active experiments

    NASA Astrophysics Data System (ADS)

    Bagno, Iu. D.; Kim, V. Iu.; Namazov, S. A.; Panchenko, V. N.; Khar'kov, I. P.

    1993-01-01

    The paper presents a description of a mobile multichannel Doppler system designed for shipboard studies of the modified ionosphere. The system was used for the diagnostics of the modified ionosphere in active experiments carried out in equatorial and low-latitude regions using the MR-20 geophysical rockets as well as in satellite experiments in the framework of the CRRES project. The data processing method is discussed, and experimental data are presented.

  15. 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

  16. 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

  17. 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.

  18. Wearable Systems for Monitoring Mobility-Related Activities in Chronic Disease: A Systematic Review

    PubMed Central

    Allet, Lara; Knols, Ruud H.; Shirato, Kei; de Bruin, Eling D.

    2010-01-01

    The use of wearable motion sensing technology offers important advantages over conventional methods for obtaining measures of physical activity and/or physical functioning in individuals with chronic diseases. This review aims to identify the actual state of applying wearable systems for monitoring mobility-related activity in individuals with chronic disease conditions. In this review we focus on technologies and applications, feasibility and adherence aspects, and clinical relevance of wearable motion sensing technology. PubMed (Medline since 1990), PEdro, and reference lists of all relevant articles were searched. Two authors independently reviewed randomised trials systematically. The quality of selected articles was scored and study results were summarised and discussed. 163 abstracts were considered. After application of inclusion criteria and full text reading, 25 articles were taken into account in a full text review. Twelve of these papers evaluated walking with pedometers, seven used uniaxial accelerometers to assess physical activity, six used multiaxial accelerometers, and two papers used a combination approach of a pedometer and a multiaxial accelerometer for obtaining overall activity and energy expenditure measures. Seven studies mentioned feasibility and/or adherence aspects. The number of studies that use movement sensors for monitoring of activity patterns in chronic disease (postural transitions, time spent in certain positions or activities) is nonexistent on the RCT level of study design. Although feasible methods for monitoring human mobility are available, evidence-based clinical applications of these methods in individuals with chronic diseases are in need of further development. PMID:22163393

  19. Column-coupling strategies for multidimensional electrophoretic separation techniques.

    PubMed

    Kler, Pablo A; Sydes, Daniel; Huhn, Carolin

    2015-01-01

    Multidimensional electrophoretic separations represent one of the most common strategies for dealing with the analysis of complex samples. In recent years we have been witnessing the explosive growth of separation techniques for the analysis of complex samples in applications ranging from life sciences to industry. In this sense, electrophoretic separations offer several strategic advantages such as excellent separation efficiency, different methods with a broad range of separation mechanisms, and low liquid consumption generating less waste effluents and lower costs per analysis, among others. Despite their impressive separation efficiency, multidimensional electrophoretic separations present some drawbacks that have delayed their extensive use: the volumes of the columns, and consequently of the injected sample, are significantly smaller compared to other analytical techniques, thus the coupling interfaces between two separations components must be very efficient in terms of providing geometrical precision with low dead volume. Likewise, very sensitive detection systems are required. Additionally, in electrophoretic separation techniques, the surface properties of the columns play a fundamental role for electroosmosis as well as the unwanted adsorption of proteins or other complex biomolecules. In this sense the requirements for an efficient coupling for electrophoretic separation techniques involve several aspects related to microfluidics and physicochemical interactions of the electrolyte solutions and the solid capillary walls. It is interesting to see how these multidimensional electrophoretic separation techniques have been used jointly with different detection techniques, for intermediate detection as well as for final identification and quantification, particularly important in the case of mass spectrometry. In this work we present a critical review about the different strategies for coupling two or more electrophoretic separation techniques and the

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

    DOE PAGESBeta

    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

  1. 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

  2. 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.

  3. 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

  4. 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

  5. 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

  6. Exploring Cold Trapped Volatiles from Stationary Landers and Mobile Rovers: ESA Activities for Resource Prospecting at the Poles

    NASA Astrophysics Data System (ADS)

    Carpenter, J. D.; Fisackerly, R.; Aziz, S.; Houdou, B.

    2015-10-01

    An overview of ESA activities in the area of measuring cold trapped volatiles in-situ, including the PROSPECT package for the Russian Luna-27 mission and the development of mobile platform capabilities that could be applied to future missions.

  7. A comparison of the acoustic mobility and the electrophoretic mobility of coal dispersions

    SciTech Connect

    Marlow, B.J.; Rowell, R.L.

    1987-04-01

    Aqueous coal dispersions play a major role from mining to the utilization of coal. The properties of these dispersions, such as stability towards aggregation, rheology, etc., are controlled by two major factors, namely, the particle size and interfacial chemistry. The interfacial chemistry is controlled by the interactions of the coal surface with the aqueous phase. Coal surface-aqueous phase interactions are controlled by rank, mineral content, surface functional groups, pore structure, adsorption, pH, ionic strength, etc. These interactions can be probed using electrokinetic techniques. The authors describe a new electrokinetic technique that utilizes ultrasonics and preliminary data on the application of this technique to coal dispersions. The advantage of ultrasonics are virtually any particle size can be used from ions to aggregates, any concentration of the dispersed phase can be used from the ppm range to volume filling networks, and samples can be optically opaque.

  8. 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.

  9. User experiences of mobile controlled games for activation, rehabilitation and recreation of elderly and physically impaired.

    PubMed

    Sirkka, Andrew; Merilampi, Sari; Koivisto, Antti; Leinonen, Markus; Leino, Mirka

    2012-01-01

    The purpose of this paper was to study how aged people experience mobile controlled game as a method of rehabilitation and recreation. The target group contained persons 70+ years of age living in assisted living conditions (N=34). The average age of the participants was 85.9 years. Women (n=17) and men (n=17) were equally presented in the sample group. Only 12 % (n=4) of participants were involved in an active weekly-based rehabilitation, light physical sitting exercises 38% (n=13). Three (n=3) of the participants (9%) used computers (net banking), and 20 (59%) used mobile phones on daily basis. Social activities and physical activation seem to be rather inadequate and traditional in assisted living organizations. The overall experiences of mobile controlled game described in this paper appeared to be a successful experiment also proving that the elderly are not as reluctant to use technical devices or playing virtual games as often thought. The game was reckoned very motivating, interesting, and entertaining both by the aged and the staff. Activation, rehabilitation and recreation in the elderly homes or assisted living organizations could benefit from utilization of new technology providing new ways and solutions that motivate the users and offer also possibilities for measuring and follow-up of the physical impacts. The future goals to improve the game were set according to the feedback given in this survey: a) wider variety of controlling modes for the game, b) developing various difficulty levels, c) developing the game to support different kinds of body movements, d) easily modified according to the individual user's exercising or rehabilitation needs as well as e) emphasizing the social aspects of the game by producing multiplayer versions. PMID:22942069

  10. 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.

  11. Active-site mobility revealed by the crystal structure of arylmalonate decarboxylase from Bordetella bronchiseptica.

    PubMed

    Kuettner, E Bartholomeus; Keim, Antje; Kircher, Markus; Rosmus, Susann; Sträter, Norbert

    2008-03-21

    Arylmalonate decarboxylase (AMDase) from Bordetella bronchiseptica catalyzes the enantioselective decarboxylation of arylmethylmalonates without the need for an organic cofactor or metal ion. The decarboxylation reaction is of interest for the synthesis of fine chemicals. As basis for an analysis of the catalytic mechanism of AMDase and for a rational enzyme design, we determined the X-ray structure of the enzyme up to 1.9 A resolution. Like the distantly related aspartate or glutamate racemases, AMDase has an aspartate transcarbamoylase fold consisting of two alpha/beta domains related by a pseudo dyad. However, the domain orientation of AMDase differs by about 30 degrees from that of the glutamate racemases, and also significant differences in active-site structures are observed. In the crystals, four independent subunits showing different conformations of active-site loops are present. This finding is likely to reflect the active-site mobility necessary for catalytic activity. PMID:18258259

  12. 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.

  13. Effects of social activation and physical mobilization on sleep in nursing home residents.

    PubMed

    Kuck, Joachim; Pantke, Michaela; Flick, Uwe

    2014-01-01

    Age-related changes in sleep physiology, frequent occurrence of health impairments, and a sedentary lifestyle make nursing home residents particularly vulnerable to sleep disturbances. Despite the high prevalence of sleep disturbances in nursing homes, there is a lack of research concerning the use of non-pharmacological approaches for improving residents' sleep. This study aimed to promote residents' sleep by improving their social activation and physical mobilization. An experimental group of residents attending an activation program four times a week during an eight-week study course was compared to a non-treated control group in a cluster-randomized intervention trial among 85 residents of 20 nursing homes. Sleep was assessed by the Insomnia Severity Index (ISI), nurses' ratings of residents' sleep disturbances and actigraphy-based sleep parameters. Although no changes in actigraphy-based sleep parameters were observed, the subjective sleep quality ratings of the intervention participants significantly improved compared to the control group members (p = 0.004). This study suggests that physical mobilization and social activation may improve residents' subjective sleep quality. Further efforts to improve residents' sleep by increasing their physical and social activity should consider existing obstacles to encourage participation and adherence to the program. PMID:25270432

  14. Localized CCR2 Activation in the Bone Marrow Niche Mobilizes Monocytes by Desensitizing CXCR4

    PubMed Central

    Park, Jeong Eun; Miller, Richard J.

    2015-01-01

    Inflammatory (classical) monocytes residing in the bone marrow must enter the bloodstream in order to combat microbe infection. These monocytes express high levels of CCR2, a chemokine receptor whose activation is required for them to exit the bone marrow. How CCR2 is locally activated in the bone marrow and how their activation promotes monocyte egress is not understood. Here, we have used double transgenic lines that can visualize CCR2 activation in vivo and show that its chemokine ligand CCL2 is acutely released by stromal cells in the bone marrow, which make direct contact with CCR2-expressing monocytes. These monocytes also express CXCR4, whose activation immobilizes cells in the bone marrow, and are in contact with stromal cells expressing CXCL12, the CXCR4 ligand. During the inflammatory response, CCL2 is released and activates the CCR2 on neighboring monocytes. We demonstrate that acutely isolated bone marrow cells co-express CCR2 and CXCR4, and CCR2 activation desensitizes CXCR4. Inhibiting CXCR4 by a specific receptor antagonist in mice causes CCR2-expressing cells to exit the bone marrow in absence of inflammatory insults. Taken together, these results suggest a novel mechanism whereby the local activation of CCR2 on monocytes in the bone marrow attenuates an anchoring signalling provided by CXCR4 expressed by the same cell and mobilizes the bone marrow monocyte to the blood stream. Our results also provide a generalizable model that cross-desensitization of chemokine receptors fine-tunes cell mobility by integrating multiple chemokine signals. PMID:26029924

  15. Quantitative determination of residual active pharmaceutical ingredients and intermediates on equipment surfaces by ion mobility spectrometry.

    PubMed

    Qin, C; Granger, A; Papov, V; McCaffrey, J; Norwood, D L

    2010-01-01

    Ion mobility spectrometry (IMS) is an analytical technique that separates ions based on their gas phase mobility at atmospheric pressure. Since gas phase ion mobility is a function of the shape and structure of the ion, this technique has the potential to provide unique specificity and selectivity. Furthermore, IMS is very sensitive (subnanogram detection limits for many small molecules), and a single analysis is typically completed within 1 min. In principle, these features of IMS should make it an ideal choice for use in cleaning verification analysis of pharmaceutical manufacturing equipment. This report describes the successful development and validation of three different equipment cleaning verification methods using IMS. The methods were developed for a specific intermediate (Compound A) in the synthetic route for a drug substance as well as for final drug substances (active pharmaceutical ingredients Compounds B and C). The cleaning verification methods were validated with respect to specificity, linearity, precision, accuracy, stability, and limit-of-quantitation. In all cases, the limits-of-quantitation were determined to be at the nanogram or sub-nanogram level. Both swab and rinse samples collected from the equipment surfaces were successfully analyzed and manufacturing equipment down-time was significantly minimized due to the reduction in cleaning verification analysis time (for example, the total analysis time for more than 30 samples using IMS was reduced to less than 2h). PMID:19758781

  16. 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

  17. 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.

  18. 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

  19. Addressing the nonexercise part of the activity continuum: a more realistic and achievable approach to activity programming for adults with mobility disability?

    PubMed

    Manns, Patricia J; Dunstan, David W; Owen, Neville; Healy, Genevieve N

    2012-04-01

    Participation in physical activity is fundamental for the maintenance of metabolic health and the prevention of major chronic diseases, particularly type 2 diabetes and cardiovascular disease. A whole-of-day approach to physical activity promotion is increasingly advocated and includes not only increasing moderate-intensity physical activity but also reducing sedentary time and increasing light-intensity activity (the "nonexercise" part of the activity continuum). This whole-of-day approach to tackling the challenge of inactivity may be particularly relevant for adults with mobility disabilities, who are among the most inactive segment of the population. Focusing on nonexercise activity by striving to reduce sedentary time and increase light-intensity activity may be a more successful place to begin to change behavior in someone with mobility disability. This article discusses what is known about the metabolic health consequences of sedentary behavior and light-intensity activity in adults with and without mobility disability. The concept of inactivity physiology is presented, along with possible applications or evidence from studies with adults with mobility disability. Mobility disability discussions and examples focus on stroke and spinal cord injury. Finally, clinical implications and future research directions related to sedentary behavior in adults with mobility disability are discussed. PMID:22156025

  20. Effects of activation of the foot on trunk mobility of patients with hemiplegia

    PubMed Central

    Kim, Young-dong

    2015-01-01

    [Purpose] The purpose of this study was to determine the effects of activation of the foot on the trunk mobility of patients with hemiplegia. [Subjects] Sixteen subjects with hemiplegia took part in the immediate group (IG), and 14 subjects with hemiplegia participated in the 2-month group (2MG). [Methods] The subjects in IG were given one leg stance training through activation of the foot only once, and 2MG received the same intervention for 30 minutes 3 times a week for, 8 weeks. The Spinal Mouse was used to collect spinal alignment data. Also, the trunk Impairment Scale (TIS) and Sensory test were used as functional tests. [Results] Sacral hip (SH), lumbar spine (LS) and thoracic spine (TS) angles in IG improved significantly, but not inclination (I), and 2MG showed increased angles of SH, LS and I, but not TS. Also, TIS Dynamic, TIS Coordination and Sensory test results of 2MG increased significantly. [Conclusion] One leg stance training through activation of the foot was effective at improving sensory input and alignment of the spine, therefore trunk mobility was improved. PMID:25995561

  1. 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

  2. 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

  3. 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

  4. 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

  5. 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

  6. Theory of electrophoretic separations. I - Formulation of a mathematical model

    NASA Technical Reports Server (NTRS)

    Saville, D. A.; Palusinski, O. A.

    1986-01-01

    A generally applicable model of electrophoretic processes is presented. The model describes the chemical reactions, treating the chemical processes as reactions at equilibrium and accounting for convection, conservation, diffusion, and electromigration of individual species as well as the relation between charge and potential. Conservation relations are described and simplified, taking advantage of the speed of the chemical reactions as compared to the transport processes to adapt the model to the electrophoretic processes involving weak electrolytes. As an application example, isotachophoresis in a one-dimensional column is considered in detail.

  7. 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.

  8. Habitual Physical Activity Levels are Associated with Performance in Measures of Physical Function and Mobility in Older Men

    PubMed Central

    Morie, Marina; Reid, Kieran F.; Miciek, Renee; Lajevardi, Newsha; Choong, Karen; Krasnoff, Joanne B.; Storer, Thomas W.; Fielding, Roger A.; Bhasin, Shalender; LeBrasseur, Nathan K.

    2010-01-01

    Objectives To determine whether objectively measured physical activity levels are associated with physical function and mobility in older men. Design Cross-sectional. Setting Academic research center. Participants Eighty-two community-dwelling men ≥ 65 years of age with self-reported mobility limitations were divided into a low activity and a high activity group based on the median average daily physical activity counts of the whole sample. Measurements Physical activity by triaxial accelerometers; physical function and mobility by the Short Physical Performance Battery (SPPB), gait speed, stair climb time, and a lift and lower task; aerobic capacity by maximum oxygen consumption (VO2max); and leg press and chest press maximal strength and peak power. Results Older men with higher compared to lower physical activity levels demonstrated a > 1.4 point higher mean SPPB score and a 0.35 m/s faster walking speed. They also climbed a standard flight of stairs 1.85 sec faster and completed 60% more shelves in a lift and lower task (all p < 0.01). Muscle strength and power measures, however, were not significantly different between the low and high activity group. Correlation analyses and multiple linear regression models showed that physical activity is positively associated with all physical function and mobility measures, leg press strength, and VO2max. Conclusion Older men with higher physical activity levels demonstrate better physical function and mobility than less active peers. Moreover, in older men physical activity levels are predictive of performance in measures of physical function and mobility. Future work is needed to determine whether modifications in physical activity levels can improve or preserve physical performance in later-life. PMID:20738436

  9. 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. PMID:19872717

  10. alpha-lytic protease can exist in two separately stable conformations with different His57 mobilities and catalytic activities.

    PubMed

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

    2005-01-25

    alpha-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

  11. 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

  12. 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

  13. 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

  14. Electrophoretic and aggregation behavior of bovine, horse and human red blood cells in plasma and in polymer solutions.

    PubMed

    Bäumler, H; Neu, B; Mitlöhner, R; Georgieva, R; Meiselman, H J; Kiesewetter, H

    2001-01-01

    The electrophoretic mobility of native and glutaraldehyde-fixed bovine, human, and horse red blood cells (RBC) was investigated as a function of ionic strength (5-150 mM) and concentration of 464 kDa dextran (2 and 3 g/dl); RBC aggregation in autologous plasma and in dextran solutions was also measured. In agreement with previous observations, human and horse RBC form stable rouleaux whereas bovine RBC do not aggregate in either plasma or in dextran 464 kDa solutions. Electrophoretic measurements showed a species-dependent adsorption and depletion of dextran that can be theoretically evaluated. Adsorption of polymer is not a prerequisite for RBC aggregation (bovine RBC show the highest amount of adsorbed dextran yet do not aggregate). Aggregate formation thus occurs as long as the Gibbs free energy difference, given by the osmotic pressure difference between the bulk phase and the polymer-depleted region between two RBC, is larger than the steric and electrostatic repulsive energy contributed by the macromolecules present on the RBC surface. With increasing bulk-phase polymer concentration the depletion layer thickness decreases and the amount of adsorbed macromolecules increases, thereby resulting in an increase of the repulsive component of the interaction energy and decreased aggregation. We thus view electrophoretic measurements of RBC in various media as an important tool for understanding polymer behavior near the red cell surface and hence the mechanisms involved in RBC aggregation. PMID:11381164

  15. 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.

  16. 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.

  17. 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.

  18. 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

  19. 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 §...

  20. 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 §...

  1. 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 §...

  2. 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 §...

  3. 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

  4. Peripheral and spinal activation of cannabinoid receptors by joint mobilization alleviates postoperative pain in mice.

    PubMed

    Martins, D F; Mazzardo-Martins, L; Cidral-Filho, F J; Gadotti, V M; Santos, A R S

    2013-01-01

    The present study was undertaken to investigate the relative contribution of cannabinoid receptors (CBRs) subtypes and to analyze cannabimimetic mechanisms involved in the inhibition of anandamide (AEA) and 2-arachidonoyl glycerol degradation on the antihyperalgesic effect of ankle joint mobilization (AJM). Mice (25-35g) were subjected to plantar incision (PI) and 24h after surgery animals received the following treatments, AJM for 9min, AEA (10mg/kg, intraperitoneal [i.p.]), WIN 55,212-2 (1.5mg/kg, i.p.), URB937 (0.01-1mg/kg, i.p.; a fatty acid amide hydrolase [FAAH] inhibitor) or JZL184 (0.016-16mg/kg, i.p.; a monoacylglycerol lipase [MAGL] inhibitor). Withdrawal frequency to mechanical stimuli was assessed 24h after PI and at different time intervals after treatments. Receptor specificity was investigated using selective CB1R (AM281) and CB2R (AM630) antagonists. In addition, the effect of the FAAH and MAGL inhibitors on the antihyperalgesic action of AJM was investigated. AJM, AEA, WIN 55,212-2, URB937 and JZL184 decreased mechanical hyperalgesia induced by PI. The antihyperalgesic effect of AJM was reversed by pretreatment with AM281 given by intraperitoneal and intrathecal routes, but not intraplantarly. Additionally, intraperitoneal and intraplantar, but not intrathecal administration of AM630 blocked AJM-induced antihyperalgesia. Interestingly, in mice pretreated with FAAH or the MAGL inhibitor the antihyperalgesic effect of AJM was significantly longer. This article presents data addressing the CBR mechanisms underlying the antihyperalgesic activity of joint mobilization as well as of the endocannabinoid catabolic enzyme inhibitors in the mouse postoperative pain model. Joint mobilization and these enzymes offer potential targets to treat postoperative pain. PMID:24120553

  5. 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

  6. Active defense scheme against DDoS based on mobile agent and network control in network confrontation

    NASA Astrophysics Data System (ADS)

    Luo, Rong; Li, Junshan; Ye, Xia; Wang, Rui

    2013-03-01

    In order to effective defend DDoS attacks in network confrontation, an active defense scheme against DDoS is built based on Mobile Agent and network control. A distributed collaborative active defense model is constructed by using mobile agent technology and encapsulating a variety of DDoS defense techniques. Meanwhile the network control theory is applied to establish a network confrontation's control model for DDoS to control the active defense process. It provides a new idea to solve the DDoS problem.

  7. Electrophoresis system for high temperature mobility measurements of nanosize particles

    NASA Astrophysics Data System (ADS)

    Rodriguez-Santiago, Victor; Fedkin, Mark V.; Lvov, Serguei N.

    2008-09-01

    The electrophoretic mobility, which reflects the zeta potential of a solid material, is an important experimental quantity providing information about the electrical double layer at the solid/liquid interface. A new high temperature electrophoresis cell was developed suitable for electrophoretic mobility measurements of dispersed nanosize particles up to 150 °C and 40 bars. Amorphous silica (SiO2) particle size standards were used to test the particle size detection limit of the new instrument at 25, 100, and 150 °C and several pH values. The microscopic detection of the particles was enabled by dark-field illumination, which allowed extending the previously available capabilities and provided higher accuracy of the electrophoretic mobility data. The electrophoretic mobility measurements for SiO2 at temperatures above 100 °C were reported for the first time and indicated a gradual increase in particle electrophoretic response with increasing temperature. The obtained data indicated negatively charged SiO2 surface throughout the pH and temperature ranges studied.

  8. 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. PMID:27374255

  9. Electrophoretic Separation of Single Particles Using Nanoscale Thermoplastic Columns.

    PubMed

    Weerakoon-Ratnayake, Kumuditha M; Uba, Franklin I; Oliver-Calixte, Nyoté J; Soper, Steven A

    2016-04-01

    Phenomena associated with microscale electrophoresis separations cannot, in many cases, be applied to the nanoscale. Thus, understanding the electrophoretic characteristics associated with the nanoscale will help formulate relevant strategies that can optimize the performance of separations carried out on columns with at least one dimension below 150 nm. Electric double layer (EDL) overlap, diffusion, and adsorption/desorption properties and/or dielectrophoretic effects giving rise to stick/slip motion are some of the processes that can play a role in determining the efficiency of nanoscale electrophoretic separations. We investigated the performance characteristics of electrophoretic separations carried out in nanoslits fabricated in poly(methyl methacrylate), PMMA, devices. Silver nanoparticles (AgNPs) were used as the model system with tracking of their transport via dark field microscopy and localized surface plasmon resonance. AgNPs capped with citrate groups and the negatively charged PMMA walls (induced by O2 plasma modification of the nanoslit walls) enabled separations that were not apparent when these particles were electrophoresed in microscale columns. The separation of AgNPs based on their size without the need for buffer additives using PMMA nanoslit devices is demonstrated herein. Operational parameters such as the electric field strength, nanoslit dimensions, and buffer composition were evaluated as to their effects on the electrophoretic performance, both in terms of efficiency (plate numbers) and resolution. Electrophoretic separations performed at high electric field strengths (>200 V/cm) resulted in higher plate numbers compared to lower fields due to the absence of stick/slip motion at the higher electric field strengths. Indeed, 60 nm AgNPs could be separated from 100 nm particles in free solution using nanoscale electrophoresis with 100 μm long columns. PMID:26963496

  10. Molluscan mobile elements similar to the vertebrate recombination-activating genes

    PubMed Central

    Panchin, Yuri; Moroz, Leonid L.

    2009-01-01

    Animal genomes contain ~20,000 genes. Additionally millions of genes for antigen receptors are generated in cells of the immune system from the sets of separate gene segments by a mechanism known as the V(D)J somatic recombination. The components of the V(D)J recombination system, Recombination-Activating Gene proteins (RAG1 and RAG2) and recombination signal sequence (RSS), are thought to have “entered” the vertebrate genome as a hypothetical “RAG transposon”. Recently discovered mobile elements have terminal inverted repeats (TIRs) similar to RSS and may encode proteins with a different degree of similarity to RAG1. We describe a novel N-RAG-TP transposon identified from the sea slug Aplysia californica that encodes a protein similar to the N-terminal part of RAG1 in vertebrates. This refines the “RAG transposon” hypothesis and allows us to propose a scenario for V(D)J recombination machinery evolution from a relic transposon related to the existing mobile elements N-RAG-TP, Chapaev and Transib. PMID:18313399

  11. Ultrasonic Localization of Mobile Robot Using Active Beacons and Code Correlation

    NASA Astrophysics Data System (ADS)

    Peca, Marek

    Ultrasonic localization system for planar mobile robot inside of a restricted field is presented. System is based on stationary active beacons and measurement of distances between beacons and robot, using cross-correlation of pseudorandom binary sequences (PRBSes). Due to high demand of dynamic reserve imposed by range ratio in our specific task, both code- as well as frequency-divided media access has been utilized. For the same reason, 1-bit signal quantization has been abandoned in favor of higher resolution in receiver analog-to-digital conversion. Finally, dynamic estimation of the position is recommended over analytic calculation. The final solution uses the extended Kalman filter (EKF), equipped with erroneous measurement detection, initial state computation, and recovery from being lost. EKF also performs data-fusion with odometry measurement. Unlike the approach in majority of works on mobile robot localization, a model, actuated solely by additive process noise, is presented for the data-fusion. It offers estimation of heading angle, and remains locally observable. Simplistic double integrator model of motion dynamics is described, and the importance of clock dynamics is emphasized.

  12. 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. PMID:16216301

  13. Analyte zone sharpening in pressurized capillary electrochromatography based on electrophoretic migration under a heterogeneous field.

    PubMed

    Kitagawa, Shinya; Buno, Hiroki; Sakabe, Koichi; Nakagawa, Hiroyuki; Ohtani, Hajime

    2014-11-01

    Significant peak width reductions, or peak height enhancements, of angiotensins were observed when a high voltage was applied to hydrophilic interaction pressurized capillary electrochromatography using gradient elution with mobile phases containing perchloric acid. The investigation using a contactless conductivity detector revealed that perchloric acid was adsorbed on the surface of the stationary phase, when the acetonitrile content in the mobile phase was high, and released from the stationary phase by increasing the water content during a gradient procedure. The released perchloric acid formed a highly concentrated zone moving from the column inlet to the outlet. The electrochromatographic behavior of the analytes, primarily electrophoretic migration, was changed in this zone. As a consequence of the significant variation in migration velocity of the analytes, the sample band width was reduced similar fashion to on-capillary concentration in capillary electrophoresis. Using this result, the reduction of band width and enhancement in separation efficiency was demonstrated in reversed-phase pressurized electrochromatography, in which the conductivity of the mobile phase was significantly altered using a step gradient. The resolution between benzoic acid and 1-naphthalene sulfonic acid was successfully improved from 2.7 to 4.3 by using the band width reduction method based on field-amplified stacking. PMID:25115853

  14. 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

  15. 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

  16. Thermally activated electron capture by mobile protons in SiO{sub 2} thin films

    SciTech Connect

    Vanheusden, K.; Karna, S.P.; Pugh, R.D.; Warren, W.L.; Fleetwood, D.M.; Devine, R.A.

    1998-01-01

    The annihilation of mobile protons in thin SiO{sub 2} films by capture of ultraviolet-excited electrons has been analyzed for temperatures between 77 and 500 K. We observe a strong increase in proton annihilation with increasing temperature, and derive an activation energy for electron capture of about 0.2 eV. Based on quantum chemical [(OH){sub 3}Si]{sub 2}{endash}O{endash}H{sup +} cluster calculations, we suggest photoexcitation of electrons from excited vibrational states of the ground electronic (valence band) state to a nearby excited electronic (SiO{sub 2} gap) state. It is argued that the latter excitation can result in H{sup 0} formation at elevated temperatures. {copyright} {ital 1998 American Institute of Physics.}

  17. Possible mechanisms of normal amylase activity in hyperlipemic pancreatitis.

    PubMed Central

    Mishkin, S.; Bates, J.; O'Hashi, J.; Schneider, P.; Sniderman, A. D.; Wolf, R. O.

    1976-01-01

    Lipemic serum from three patients with acute pancreatitis and type IV hyperlipemia was fractionated into very-low-density lipoproteins and clear serum. Amylase activity (determined by the Phadebas method) in the component fractions did not exceed that in the original lipemic serum. Addition of these fractions or VLDL and chylomicrons from asymptomatic patients with hyperlipemia to nonlipemic serum from patients with "routine acute pancreatitis" did not inhibit amylase activity or alter the electrophoretic mobility of amylase isoenzymes. Therefore the normal amylase activity often observed in hyperlipemic pancreatitis does not result from an inhibition of amylase activity by serum lipoproteins. Images FIG. 4 FIG. 5 PMID:206333

  18. Calcium mobilization and phosphoinositide turnover in fluoride-activated human neutrophils

    SciTech Connect

    Strnad, C.F.; Wong, K.

    1986-05-01

    Fluoride ion, at concentrations above 10 mM, has been found to activate a superoxide production response in human neutrophils which is strongly dependent on the presence of extracellular calcium. In an attempt to further explore the calcium requirement of fluoride-induced neutrophil activation, intracellular calcium concentrations were monitored through use of the fluorescent calcium probe, Quin 2. Fluoride ion, at concentrations between 10 and 20 mM, was found to elicit a rise in intracellular calcium levels which was characterized by a lag period of 4 to 10 min and a prolonged duration of action (greater than 20 min). In contrast, the chemotactic peptide, formylmethionyl-leucyl-phenylalanine (FMLP), induced a rise in intracellular calcium concentration which peaked within 1 min. Preincubation of cells with 1 ..mu..g/ml pertussis toxin resulted in inhibition of the FMLP-induced response, but not that elicited by fluoride. Furthermore, anion exchange chromatography indicated that inositol phosphate accumulation occurred in fluoride-treated cells in association with calcium mobilization. Recent evidence suggests that the FMLP receptor is coupled to phospholipase C and phosphoinositide turnover through a guanine nucleotide binding protein susceptible to inhibition by pertussis toxin. Present results suggest that fluoride ion may serve to activate this protein in a manner resistant to inhibition by pertussis toxin.

  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. Electrophoretic determination of calystegines A3 and B2 in potato.

    PubMed

    Kvasnicka, Frantisek; Jockovic, Nebojsa; Dräger, Birgit; Sevcík, Rudolf; Cepl, Jaroslav; Voldrich, Michal

    2008-02-15

    Potatoes, members of the Solanaceae plant family, contain calystegines, water-soluble nortropane alkaloids, which are biologically active as glycosidase inhibitors. The content of calystegines A(3) and B(2) in different varieties of potato and in various parts of the tubers (whole potato, peel, flesh, and sprouts) were analysed by new capillary zone electrophoresis and capillary isotachophoresis methods and by the routine GC method. The optimized background electrolyte for capillary zone electrophoretic analysis was mixture of 20 mM histidine, 20 mM N,N-bis(2-hydroxyethyl)-2-aminoethanesulfonic acid and 20% (v/v) methanol in demineralized water. Calystegines were detected by indirect UV detection at 210 nm. A clear separation of calystegines from other components of the methanolic sample extract was achieved within 4 min. The electrolytes for isotachophoretic analysis consisted of 5 mM NH(4)OH, 10 mM N,N-bis(2-hydroxyethyl)-2-aminoethanesulfonic acid, 0.1% hydroxyethylcellulose and 20% (v/v) methanol in demineralized water (leading) and 5 mM histidine+10 mM acetic acid+20% (v/v) methanol in demineralized water (terminating). Calystegines were separated within 20 min and detected by a conductimeter. Method characteristics of both zone electrophoresis and isotachophoresis, i.e., linearity (10-100 ng/microl and 1-10 ng/microl), accuracy (recovery 96+/-5% and 98+/-4%), intra-assay repeatability (4.2% and 3.5%), and detection limit (3 and 0.4 ng/microl) were evaluated. Simple sample preparation, sufficient sensitivity, speed of analysis, and low running cost are important attributes of the electrophoretic methods. The overall results of electrophoretic methods were comparable with GC. PMID:18178214

  1. [A new electrophoretic method for coating metalceramic elements with opaque].

    PubMed

    Weber, H

    1979-05-01

    A new, electrophoretical method of coating dental alloys (Au or Ni-Cr) with opaque is described for the first time. The comparison of this method with the known wet brush technique shows that bubbles or voids might occur at the interface between metal and opaque when applying the first ceramic layer manually whereas the electrophoretical one generates a thin and dense layer of porcelain being free of voids within the adherence zone. Those bubbles are considered to be inherent with the brush technique. The author suggests to galvanize dental alloys particularly noble metals in order to suppress any anodic reactions. General advantage for the bond due to galvanization are expected no matter how the opaque was applied. PMID:380960

  2. EFFECT OF STRUCTURED PHYSICAL ACTIVITY ON SLEEP-WAKE BEHAVIORS IN SEDENTARY ELDERS WITH MOBILITY LIMITATIONS

    PubMed Central

    Vaz Fragoso, Carlos A.; Miller, Michael E.; King, Abby C.; Kritchevsky, Stephen B.; Liu, Christine K.; Myers, Valerie H.; Nadkarni, Neelesh K.; Pahor, Marco; Spring, Bonnie J.; Gill, Thomas M.

    2016-01-01

    OBJECTIVE To evaluate the effect of structured physical activity on sleep-wake behaviors in sedentary community-dwelling elders with mobility limitations. DESIGN Multicenter, randomized trial of moderate-intensity physical activity versus health education, with sleep-wake behaviors pre-specified as a tertiary outcome over a planned intervention period ranging between 24 and 30 months. SETTING Lifestyle Interventions and Independence in Elder (LIFE) Study. PARTICIPANTS 1635 community-dwelling persons, aged 70–89 years, who were initially sedentary with a Short Physical Performance Battery score <10. MEASUREMENTS Sleep-wake behaviors were evaluated by the Insomnia Severity Index (ISI) (≥8 defined insomnia), Epworth Sleepiness Scale (ESS) (≥10 defined daytime drowsiness), and Pittsburgh Sleep Quality Index (PSQI) (> 5 defined poor sleep quality) — administered at baseline and subsequently at 6, 18, and 30 months. RESULTS The randomized groups were similar on baseline demographic variables, including mean age (79 years) and sex (67% female). Relative to health education, structured physical activity significantly reduced the likelihood of having poor sleep quality (adjusted odds ratios [adjOR] for PSQI >5 of 0.80 [0.68, 0.94]), including a reduction in new cases (adjOR for PSQI >5 of 0.70 [0.54, 0.89]) but not in resolution of prevalent cases (adjOR for PSQI ≤5 of 1.13 [0.90, 1.43]). No significant intervention effects were observed for ISI or ESS. CONCLUSION Structured physical activity reduced the likelihood of developing poor sleep quality (PSQI >5) over the intervention period, when compared with health education, but had no effect on prevalent cases of poor sleep quality, or on sleep-wake behaviors evaluated by the ISI or ESS. These results suggest that the benefit of physical activity in this sample was preventive and limited to sleep-wake behaviors evaluated by the PSQI. PMID:26115386

  3. 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.

  4. 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 ...

  5. Mobility and Active Ageing in Suburban Environments: Findings from In-Depth Interviews and Person-Based GPS Tracking

    PubMed Central

    Zeitler, Elisabeth; Buys, Laurie; Aird, Rosemary; Miller, Evonne

    2012-01-01

    Background. Governments face a significant challenge to ensure that community environments meet the mobility needs of an ageing population. Therefore, it is critical to investigate the effect of suburban environments on the choice of transportation and its relation to participation and active ageing. Objective. This research explores if and how suburban environments impact older people's mobility and their use of different modes of transport. Methods. Data derived from GPS tracking, travel diaries, brief questionnaires, and semistructured interviews were gathered from thirteen people aged from 56 to 87 years, living in low-density suburban environments in Brisbane, Australia. Results. The suburban environment influenced the choice of transportation and out-of-home mobility. Both walkability and public transportation (access and usability) impact older people's transportation choices. Impracticality of active and public transportation within suburban environments creates car dependency in older age. Conclusion. Suburban environments often create barriers to mobility, which impedes older people's engagement in their wider community and ability to actively age in place. Further research is needed to develop approaches towards age-friendly suburban environments which will encourage older people to remain active and engaged in older age. PMID:23346108

  6. 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...

  7. Protease-Activated Receptor 4 Induces Bladder Pain through High Mobility Group Box-1

    PubMed Central

    Kouzoukas, Dimitrios E.; Ma, Fei; Meyer-Siegler, Katherine L.; Westlund, Karin N.; Hunt, David E.; Vera, Pedro L.

    2016-01-01

    Pain is the significant presenting symptom in Interstitial Cystitis/Painful Bladder Syndrome (IC/PBS). Activation of urothelial protease activated receptor 4 (PAR4) causes pain through release of urothelial macrophage migration inhibitory factor (MIF). High Mobility Group Box-1 (HMGB1), a chromatin-binding protein, mediates bladder pain (but not inflammation) in an experimental model (cyclophosphamide) of cystitis. To determine if PAR4-induced bladder hypersensitivity depends on HMGB1 downstream, we tested whether: 1) bladder PAR4 stimulation affected urothelial HMGB1 release; 2) blocking MIF inhibited urothelial HMGB1 release; and 3) blocking HMGB1 prevented PAR4-induced bladder hypersensitivity. HMGB1 release was examined in immortalized human urothelial cultures (UROtsa) exposed to PAR4-activating peptide (PAR4-AP; 100 μM; 2 hours) or scrambled control peptide. Female C57BL/6 mice, pretreated with a HMGB1 inhibitor (glycyrrhizin: 50 mg/kg; ip) or vehicle, received intravesical PAR4-AP or a control peptide (100 μM; 1 hour) to determine 1) HMGB1 levels at 1 hour in the intravesical fluid (released HMGB1) and urothelium, and 2) abdominal hypersensitivity to von Frey filament stimulation 24 hours later. We also tested mice pretreated with a MIF blocker (ISO-1: 20 mg/kg; ip) to determine whether MIF mediated PAR4-induced urothelial HMGB1 release. PAR4-AP triggered HMGB1 release from human (in vitro) and mice (in vivo) urothelial cells. Intravesical PAR4 activation elicited abdominal hypersensitivity in mice that was prevented by blocking HMGB1. MIF inhibition prevented PAR4-mediated HMGB1 release from mouse urothelium. Urothelial MIF and HGMB1 represent novel targets for therapeutic intervention in bladder pain conditions. PMID:27010488

  8. 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.

  9. 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

  10. Microfluidic Mobility Shift Profiling of Lysine Acetyltransferases Enables Screening and Mechanistic Analysis of Cellular Acetylation Inhibitors.

    PubMed

    Sorum, Alexander W; Shrimp, Jonathan H; Roberts, Allison M; Montgomery, David C; Tiwari, Neil K; Lal-Nag, Madhu; Simeonov, Anton; Jadhav, Ajit; Meier, Jordan L

    2016-03-18

    Lysine acetyltransferases (KATs) are critical regulators of signaling in many diseases, including cancer. A major challenge in establishing the targetable functions of KATs in disease is a lack of well-characterized, cell-active KAT inhibitors. To confront this challenge, here we report a microfluidic mobility shift platform for the discovery and characterization of small molecule KAT inhibitors. Novel fluorescent peptide substrates were developed for four well-known KAT enzymes (p300, Crebbp, Morf, and Gcn5). Enzyme-catalyzed acetylation alters the electrophoretic mobility of these peptides in a microfluidic chip, allowing facile and direct monitoring of KAT activity. A pilot screen was used to demonstrate the utility of microfluidic mobility shift profiling to identify known and novel modulators of KAT activity. Real-time kinetic monitoring of KAT activity revealed that garcinol, a natural product KAT inhibitor used in cellular studies, exhibits time-dependent and detergent-sensitive inhibition, consistent with an aggregation-based mechanism. In contrast, the cell-permeable bisubstrate inhibitor Tat-CoA exhibited potent and time-independent KAT inhibition, highlighting its potential utility as a cellular inhibitor of KAT activity. These studies define microfluidic mobility shift profiling as a powerful platform for the discovery and characterization of small molecule inhibitors of KAT activity, and provide mechanistic insights potentially important for the application of KAT inhibitors in cellular contexts. PMID:26428393

  11. 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.

  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. 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

  15. Impaired neural activation limits muscle power in mobility-limited older adults

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Declines in functional mobility are common with advancing age, though the physiological determinants underlying this problem are not fully understood. Accumulating evidence indicates that muscle power, the product of force and velocity, is an independent predictor of mobility function in older adul...

  16. Electrophoretic isolation of saponin fractions from Saponinum album and their evaluation in synergistically enhancing the receptor-specific cytotoxicity of targeted toxins.

    PubMed

    Thakur, Mayank; Weng, Alexander; Bachran, Diana; Riese, Sebastian B; Böttger, Stefan; Melzig, Matthias F; Fuchs, Hendrik

    2011-11-01

    Saponinum album (SA) is a commercial mixture of saponins isolated from Gypsophila species. In the previously published work, we reported that SA dramatically improves the inhibition of tumor growth by targeted toxins in mice in a synergistic way. Here we report a simplified electrophoretic method for the isolation of a highly effective fraction of SA with a relative electrophoretic mobility to the dye front (R(f) ) of 0.63 from the mixture. In total, four different fractions were separated at a preparative scale, and evaluated by ESI-MS, HPLC and TLC analysis. Electrophoretic mobility and electrochemical properties of the different fractions of saponins from SA were set into relation to their ability to enhance the cytotoxicity of epidermal growth factor (EGF)-based targeted toxins. We here treated HER-14 cells, which are NIH-3T3 Swiss mouse embryo cells transfected with the human EGF receptor. Untransfected NIH-3T3 cells served as control. The major bulk of SA (72.3%) (R(f) =0.78) migrated the farthest and was found to be significantly ineffective (p<0.05) in enhancing the cytotoxicity of the targeted toxin, while the second fraction (R(f) =0.63) showed an enhancement of 9800-fold. The third (R(f) =0.56) had an enhancement factor of 3200, the fourth (R(f) =0.08) was again significantly ineffective (p<0.05) in exhibiting any enhancement of cytotoxicity. PMID:21997431

  17. Asesssment of mobile gamma-scanning van activities in Edgemont, South Dakota. [UMTRA program

    SciTech Connect

    Not Available

    1986-04-01

    All accessible thoroughfares in an area in Edgemont, South Dakota, comprising approximately 800 properties, were traversed by a mobile gamma-ray scanning van operated by Oak Ridge National Laboratory (ORNL). The purpose of the mobile survey was to identify residual radioactive contamination on properties in the vicinity of the nearby uranium tailings pile. The properties identified by mobile scanning (herein referred to as anomalies) were compared with results from walk-on measurements conducted by Battelle Pacific Northwest Laboratories (PNL). The mobile scan was successful in identifying 48% of the properties previously identified as contaminated by PNL walk-on measurements. Modification of the algorithm used by the mobile scanning van to identify radioactive contamination from the measured gamma radiation resulted in mixed success; the number of successful identifications increased but the number of false identifications increased disproportionately and unacceptably.

  18. 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?

  19. 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.

  20. 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

  1. Activity and Ca2+ regulate the mobility of TRPV1 channels in the plasma membrane of sensory neurons

    PubMed Central

    Senning, Eric N; Gordon, Sharona E

    2015-01-01

    TRPV1 channels are gated by a variety of thermal, chemical, and mechanical stimuli. We used optical recording of Ca2+ influx through TRPV1 to measure activity and mobility of single TRPV1 molecules in isolated dorsal root ganglion neurons and cell lines. The opening of single TRPV1 channels produced sparklets, representing localized regions of elevated Ca2+. Unlike sparklets reported for L-type Ca2+ channels, TRPV4 channels, and AchR channels, TRPV1 channels diffused laterally in the plasma membrane as they gated. Mobility was highly variable from channel-to-channel and, to a smaller extent, from cell to cell. Most surprisingly, we found that mobility decreased upon channel activation by capsaicin, but only in the presence of extracellular Ca2+. We propose that decreased mobility of open TRPV1 could act as a diffusion trap to concentrate channels in cell regions with high activity. DOI: http://dx.doi.org/10.7554/eLife.03819.001 PMID:25569155

  2. Electrophoretic Deposition of Chitosan Coatings Modified with Gelatin Nanospheres To Tune the Release of Antibiotics.

    PubMed

    Song, Jiankang; Chen, Qiang; Zhang, Yang; Diba, Mani; Kolwijck, Eva; Shao, Jinlong; Jansen, John A; Yang, Fang; Boccaccini, Aldo R; Leeuwenburgh, Sander C G

    2016-06-01

    Orthopedic and dental implants are increasingly used in the medical field in view of their high success rates. Implant-associated infections, however, still occur and are difficult to treat. To combat these infections, the application of an active coating to the implant surface is advocated as an effective strategy to facilitate sustained release of antibacterial drugs from implant surfaces. Control over this release is, however, still a major challenge. To overcome this problem, we deposited composite coatings composed of a chitosan matrix containing gelatin nanospheres loaded with antibiotics onto stainless steel plates by means of the electrophoretic deposition technique. The gelatin nanospheres were distributed homogeneously throughout the coatings. The surface roughness and wettability of the coatings could be tuned by a simple adjustment of the weight ratio between the gelatin nanospheres and chitosan. Vancomycin and moxifloxacin were released in sustained and burst-type manners, respectively, while the coatings were highly cytocompatible. The antibacterial efficacy of the coatings containing different amounts of antibiotics was tested using a zone of inhibition test against Staphylococcus aureus, which showed that the coatings containing moxifloxacin exhibited an obvious inhibition zone. The coatings containing a high amount of vancomycin were able to kill bacteria in direct contact with the implant surface. These results suggest that the antibacterial capacity of metallic implants can be tuned by orthogonal control over the release of (multiple) antibiotics from electrophoretically deposited composite coatings, which offers a new strategy to prevent orthopedic implant-associated infections. PMID:27167424

  3. Electrophoretic deposition of tetracycline modified silk fibroin coatings for functionalization of titanium surfaces

    NASA Astrophysics Data System (ADS)

    Zhang, Zhen; Qu, Yinying; Li, Xiaoshuang; Zhang, Sheng; Wei, Qingsong; Shi, Yusheng; Chen, Lili

    2014-06-01

    Electrophoretic deposition has been widely used for the fabrication of functional coatings onto metal implant. A characteristic feature of this process is that positively charged materials migrate toward the cathode and can deposit on it. In this study, silk fibroin was decorated with tetracycline in aqueous solution to impart positive charge, and then deposited on negatively titanium cathode under certain electric field. The characterization of the obtained coatings indicated that the intermolecular hydrogen bonds formed between the backbone of silk fibroin and tetracycline molecular. In vitro biological tests demonstrated that osteoblast-like cells achieved acceptable cell affinity on the tetracycline cross-linked silk fibroin coatings, although greater cell viability was seen on pure silk fibroin coatings. The cationic silk fibroin coatings showed remarkable antibacterial activity against gram-positive (Staphylococcus aureus) and gram-negative (Escherichia coli) bacteria. Therefore, we concluded that electrophoretic deposition was an effective and efficient technique to prepare cationic silk fibroin coatings on the titanium surface and that cationic silk fibroin coatings with acceptable biocompatibility and antibacterial property were promising candidates for further loading of functional agents.

  4. Screening α-glucosidase inhibitors from traditional Chinese drugs by capillary electrophoresis with electrophoretically mediated microanalysis.

    PubMed

    Guo, Li-Ping; Jiang, Ting-Fu; Lv, Zhi-Hua; Wang, Yuan-Hong

    2010-12-15

    In the present study, we report the study by a combination of electrophoretically mediated microanalysis method with a partial technique for screening alpha-glucosidase inhibitors from 21 traditional Chinese drugs. In the setup, substrates and enzymes were introduced into the capillary as distinct plugs, the electrophoretic conditions for enzyme reaction and separation of substrates and products were different in the composition and pH of the background electrolyte, which make more enzyme reactions possible. Part of the capillary was filled with the optimal buffer for the enzyme reaction, whereas the rest was filled with the background electrolyte optimal for the separation of substrates and products. With the optimal condition, the Michaelis-Menten constant and the inhibitive mechanism of acarbose were studied, which were in the same range as previous literature data. Furthermore, the inhibitory ratios of enzymatic activity (IRE) of 21 traditional Chinese drugs were determined. The classical method has superiorities over traditional assay methods, which not only minimizes the false-positive results but also simplifies the experimental processes. It could be used for screening inhibitors in natural extract. PMID:20719454

  5. Hexokinase inhibitor screening based on adenosine 5'-diphosphate determination by electrophoretically mediated microanalysis.

    PubMed

    Wang, Tongdan; Kang, Jingwu

    2009-04-01

    A CE-based method for hexokinase inhibitor screening was developed in the present paper. In this method, hexokinase activity was assayed via electrophoretically mediated microanalysis (EMMA), which combines on-column hexokinase-mediated reaction and measurement of produced adenosine 5'-diphosphate (ADP) via electrophoretical separation and UV detection. Enzyme inhibition can be read out directly from the reduced peak area of ADP in comparison with a reference electropherogram obtained in the absence of any inhibitor. Conditions for on-column enzyme reaction and separation of adenosine 5'-triphosphate (ATP) and ADP were optimized. The optimal buffer composition for enzymatic reaction was 25 mM HEPES buffer (pH 7.5) containing 5 mM MgCl(2), whereas the optimal buffer composition for separation was 100 mM Tris-phosphate buffer (pH 5.5) containing 0.02% (m/v) hexadimethrine bromide (HDB). Fortunately, discontinuous buffer system can be adapted easily in the EMMA method. The time for separation was reduced dramatically to less than 3 min by reversing the direction of EOF via dynamically coating the capillary wall with the cationic polyelectrolyte HDB. Moreover, the peak tailing of ATP was also reduced by HDB coating. The Z' factor as high as 0.98 was obtained, indicating a high quality of the screening data. The present method is simple, robust and cost-effective. PMID:19306267

  6. 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

  7. 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

  8. Thermally Activated Point Defect Diffusion in Methylammonium Lead Trihalide: Anisotropic and Ultrahigh Mobility of Iodine.

    PubMed

    Delugas, P; Caddeo, C; Filippetti, A; Mattoni, A

    2016-07-01

    We study the diffusion of point defects in crystalline methylammonium lead halide (MAPI) at finite temperatures by using all-atoms molecular dynamics. We find that, for what concerns intrinsic defects, iodine diffusion is by far the dominant mechanism of ionic transport in MAPI, with diffusivities as high as 7.4 × 10(-7) and 4.3 × 10(-6) cm(2) s(-1) at 300 K and single activation energies of 0.24 and 0.10 eV, for interstitials and vacancies, respectively. The comparison with common covalent and oxide crystals reveals the ultrahigh mobility of defects in MAPI. Though at room temperature the vacancies are about 1 order of magnitude more diffusive, the anisotropic interstitial dynamics increases more rapidly with temperature, and it can be dominant at high temperatures. Present results are fully consistent with the involvement of iodide ions in hysteresis and have implications for improvement of the material quality by better control of defect diffusion. PMID:27237630

  9. 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

  10. 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. PMID:15101385

  11. Single neuronal activities from CA3 region of hippocampus during conditioning, in mobile unanaesthetised conscious rabbits.

    PubMed

    Datta, S

    1988-01-01

    Single neuronal activities of 93 units from CA3 region of hippocampus were studied in unanaesthetised mobile rabbits. Effects of repeated reinforced conditioned stimuli (CS+) were observed on these neuronal firing pattern. The conditioned stimuli (CS) consisted of a tone 600 Hz for 6 seconds which was reinforced by a subcutaneous electrical shock (0.4 V, frequency 250 sec, and pulse width 300 microsec) for one second duration (CS+). Ten such CS+ were applied at the gap of 5 min, in between. As majority of CA3 neurons showed irregular spontaneous activities-the histograms drawn after calculation of interspike intervals showed a definite pattern of discharge which could be compared before, during and after multiple CS+. Two groups of neurons could be identified by their resting firing pattern. One group consisting of 21 neurons (22.5% approximately) showed complex spikes, with spike frequency less than 2 to 8 per sec. They were complex spike cells (CSC). The other group consisting of majority of neurons (72 neurons, 77.5% approximately) showed comparatively high spike frequency greater than 8 to 40 per sec (theta cells). Both the group of neurons reacted tonically to CS+. All complex spike cells and 54% of theta cells showed inhibitory reaction and 46% of theta cells showed excitatory reaction to CS+. But with repeated presentation (4th to 5th) of CS+ the reaction gradually declined and finally after tenth CS+ it disappeared and resting firing pattern was observed. Thus it seems that the neurons of CA3 region have an intrinsic habituation capability. The probable cause, mechanism and the significance for the habituation has been discussed here. PMID:3198239

  12. 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. PMID:23647448

  13. 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

  14. Activities of the European Conference of Posts and Telecommunications (CEPT) special Group on Mobile Communications (GSM)

    NASA Astrophysics Data System (ADS)

    Dupuis, P.

    1986-09-01

    The group on mobile communications (GSM) of the European Conference of Posts and Telecommunications is in charge of specifying a harmonized mobile radio communication system adapted to the needs and to the technological environment of the coming decades. The means at the disposal of GSM, the objectives of the system, (basic requirements), the program, and time schedule are presented. The strength of GSM and the dangers which it must avoid are pointed out.

  15. Electrophoretic lithium iron phosphate/reduced graphene oxide composite for lithium ion battery cathode application

    NASA Astrophysics Data System (ADS)

    Huang, Yuan; Liu, Hao; Lu, Yi-Chun; Hou, Yanglong; Li, Quan

    2015-06-01

    A binder/additive free composite electrode of lithium iron phosphate/reduced graphene oxide with ultrahigh lithium iron phosphate mass ratio (91.5 wt% of lithium iron phosphate) is demonstrated using electrophoresis. The quasi-spherical lithium iron phosphate particles are uniformly connected to and/or wrapped by three-dimensional networks of reduced graphene oxide nanosheets, with intimate contact formed between the two. Enhanced capacity is achieved in the electrophoretic composite cathode, when compared to either the conventional one or composite cathode formed by mechanically mixing lithium iron phosphate and reduced graphene oxide. The present methodology is simple and does not disturb the active material growth process. It can be generally applied to a variety of active material systems for both cathode and anode applications in lithium ion batteries.

  16. Tyrosinase inhibitor screening in traditional Chinese medicines by electrophoretically mediated microanalysis.

    PubMed

    Tang, Lilin; Zhang, Wenpeng; Zhao, Haiyan; Chen, Zilin

    2015-08-01

    A capillary-electrophoresis-based method for the screening of tyrosinase inhibitors in traditional Chinese medicines was developed. The method integrated electrophoretically mediated microanalysis with sandwich mode injection, partial filling, and rapid polarity switching techniques, and carried out on-column enzyme reaction and the separation of substrate and product. The conditions were optimized including the background electrolyte, mixing voltage, and the incubation time. Finally, the screening of nine standard natural compounds of traditional Chinese medicines was carried out. The inhibitors can be directly identified from the reduced peak area of the product compared to that obtained without any inhibitor. Chlorogenic acid (100 μM) showed inhibitory activity with the inhibitory percentage of 19.8%, while the other compounds showed no inhibitory activity. This method has great application potential in drug discovery from traditional Chinese medicines. PMID:26037533

  17. 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

  18. 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.

  19. 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

  20. Selectively-etched nanochannel electrophoretic and electrochemical devices

    SciTech Connect

    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.

  1. A conformationally mobile cysteine residue (Cys-561) modulates Na+ and H+ activation of human CNT3.

    PubMed

    Slugoski, Melissa D; Smith, Kyla M; Mulinta, Ras; Ng, Amy M L; Yao, Sylvia Y M; Morrison, Ellen L; Lee, Queenie O T; Zhang, Jing; Karpinski, Edward; Cass, Carol E; Baldwin, Stephen A; Young, James D

    2008-09-01

    In humans, the SLC28 concentrative nucleoside transporter (CNT) protein family is represented by three Na+-coupled members; human CNT1 (hCNT1) and hCNT2 are pyrimidine and purine nucleoside-selective, respectively, whereas hCNT3 transports both purine and pyrimidine nucleosides and nucleoside drugs. Belonging to a phylogenetic CNT subfamily distinct from hCNT1/2, hCNT3 also mediates H+/nucleoside cotransport. Using heterologous expression in Xenopus oocytes, we have characterized a cysteineless version of hCNT3 (hCNT3C-). Processed normally to the cell surface, hCNT3C- exhibited hCNT3-like transport properties, but displayed a decrease in apparent affinity specific for Na+ and not H+. Site-directed mutagenesis experiments in wild-type and hCNT3C- backgrounds identified intramembranous Cys-561 as the residue responsible for this altered Na+-binding phenotype. Alanine at this position restored Na+ binding affinity, whereas substitution with larger neutral amino acids (threonine, valine, and isoleucine) abolished hCNT3 H+-dependent nucleoside transport activity. Independent of these findings, we have established that Cys-561 is located in a mobile region of the hCNT3 translocation pore adjacent to the nucleoside binding pocket and that access of p-chloromercuribenzene sulfonate to this residue reports a specific H+-induced conformational state of the protein ( Slugoski, M. D., Ng, A. M. L., Yao, S. Y. M., Smith, K. M., Lin, C. C., Zhang, J., Karpinski, E., Cass, C. E., Baldwin, S. A., and Young, J. D. (2008) J. Biol. Chem. 283, 8496-8507 ). The present investigation validates hCNT3C- as a template for substituted cysteine accessibility method studies of CNTs and reveals a pivotal functional role for Cys-561 in Na+- as well as H+-coupled modes of hCNT3 nucleoside transport. PMID:18621735

  2. 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. PMID:3170218

  3. Weight Status and Differences in Mobility Performance, Pain Symptoms, and Physical Activity in Older, Knee Osteoarthritis Patients

    PubMed Central

    Garver, Matthew J.; Focht, Brian C.; Dials, Justin; Lucas, Alexander R.; Devor, Steven T.; Emery, Charles F.; Hackshaw, Kevin V.; Rejeski, W. Jack

    2014-01-01

    Knee osteoarthritis (OA) is a leading cause of functional disability among American adults. Obesity is a strong independent risk factor for OA. While research emphasizes the role of obesity in the OA-physical function relationship, the extent to which weight status impacts salient physical, health, and pain measures in older, knee OA patients is not well delineated. The primary aim of this study was to assess differences in mobility performance (stair climb and 400-meter walk), mobility-related self-efficacy, pain symptoms (WOMAC), and measures of accelerometer-determined physical activity (PA) as a function of weight status. Analysis of covariance was conducted to examine differences on the dependent variables. Obese class III patients were outperformed by their counterparts on nearly every measure of mobility, mobility-related self-efficacy, and the assessment of pain symptoms. These outcomes did not differ among other weight comparisons. Normal weight subjects outperformed classes I, II, and III counterparts on most measures of PA (engagement in moderate or greater PA and total weekly steps). Additionally, overweight participants outperformed obese class II participants and obese class I participants outperformed obese classes II and III participants on total weekly steps. Collectively, these findings underscore the meaningful differences observed in relevant OA outcomes as a function of increasing levels of body weight. PMID:24963401

  4. Parental perceived neighborhood attributes: associations with active transport and physical activity among 10–12 year old children and the mediating role of independent mobility

    PubMed Central

    2014-01-01

    Background During the last decades, the use of active travel modes declined in all age groups. Childhood is a critical time to establish lifelong healthy patterns. To develop effective interventions in this age group, insight in the correlates of health behaviors and the possible mediating factors is necessary. Among children, the role of parents may not be overlooked. Therefore, this study aimed to examine the associations of parental perceptions of neighborhood environmental attributes with active transport and total physical activity in 10–12 year old Belgian boys and girls. Furthermore, this study examined the potential mediating effect of independent mobility on these associations. Methods In the present study, 736 10–12 year old children and their parents from 44 elementary schools in Flanders, Belgium, participated. The children were asked to wear an activity monitor and to fill in a survey questioning demographic factors and the Flemish Physical Activity Questionnaire. The parents filled in a survey concerning demographic factors, the child’s level of independent mobility and environmental perceptions (Neighborhood Environmental Walkability Scale). Results Overall, boys reported more active transport when parents perceived more land use mix diversity, shorter distances to school, good land use mix access, higher residential density and less pleasing neighborhood aesthetics. Higher total physical activity levels were reported when parents perceived shorter distances to school and availability of walking/cycling infrastructure. None of the associations was mediated by independent mobility in boys. Girls reported more active transport when parents perceived higher residential density, more land use mix diversity, shorter distances to school, good land use mix access, available walking/cycling infrastructure and convenient recreational facilities. Girls reported higher total physical activity levels when parents perceived high residential density, good

  5. Electrophoretic karyotypes of clinical isolates of Coccidioides immitis.

    PubMed Central

    Pan, S; Cole, G T

    1992-01-01

    Chromosomes of the fungal respiratory pathogen, Coccidioides immitis, were separated by contour-clamped homogeneous electric field gel electrophoresis. Twelve isolates were examined, the majority of which showed four chromosomes with a range of molecular size from 11.5 to 3.2 Mb. Three isolates (C634, C735, and L) revealed three chromosomal bands under the conditions employed for electrophoretic separation. However, in two of these isolates (C634 and C735), four chromosomes were visible on membrane transfers of pulsed-field gels after Southern hybridization between the chromosomal DNA and selected DNA probes. The probes included a conserved ribosomal gene and three previously described cDNAs isolated from C. immitis expression libraries. The L isolate was determined to have the same genome size as a typical four-chromosome isolate on the basis of microspectrophotometric comparison of fluorescence intensity of the ethidium bromide-stained nuclear DNA. The genome size of C. immitis determined by microspectrophotometry was approximately 28.2 +/- 2.6 Mb. The calculated genome size based on addition of the average molecular weights of chromosomal bands separated by contour-clamped homogeneous electric field gel electrophoresis was approximately equal to the estimate derived from the spectrophotometric analyses. This is the first report of the electrophoretic karyotype of C. immitis. Images PMID:1398998

  6. [Analysis of proteins in food with electrophoretic and chromatographic methods].

    PubMed

    Kaiser, K P; Krause, I

    1985-03-01

    The efficiency of electrophoretic methods (gel electrophoresis, isoelectric focusing, twodimensional techniques) and of chromatographic methods (size exclusion and ion exchange chromatography, reversed phase HPLC) to analyze proteins in foods is reviewed. Several selected applications are discussed in detail. The large diversity of proteins in a particular food results in a unique electrophoretic or chromatographic pattern, that can be used for identification purposes, by means of the so called indicator proteins. The adaptability and resolving power of the methods assure their extended application to many protein containing foods. The uniqueness of the patterns obtained warranties differentiations of even closely related animal or plant foods as well as mixtures of them. The methods also allow quantitative determinations of mixtures of foods. Their ease of handling and good reproducibility and reliability favours their use in routine analyses. Numerous investigations on fish, meat and derived products, non-meat proteins in meat products, milk, cheese, cereals and products made of cereals, oilseed proteins, legumes, fruits and vegetables described in the literature are here presented. PMID:3890408

  7. 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%. PMID:24863199

  8. 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.

  9. 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. PMID:24367481

  10. 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

  11. 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...

  12. 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

  13. 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.

  14. 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.

  15. 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.

  16. Designing iCanFit: A Mobile-Enabled Web Application to Promote Physical Activity for Older Cancer Survivors

    PubMed Central

    Dahlke, Deborah Vollmer; Ory, Marcia; Hochhalter, Angela; Reynolds, Jana; Purcell, Ninfa Pena; Talwar, Divya; Eugene, Nola

    2013-01-01

    Background Most older cancer survivors (OCS) do not engage in regular physical activity (PA) despite well-known health benefits. With the increased use of mobile technologies among older adults, mobile tools may be an effective method to deliver PA promotion programs for OCS. Objective To document the process of designing an OCS-friendly mobile-enabled Web application of PA promotion program. Methods Mixed methods encompassing group discussions, individual interviews, and brief surveys with community leaders, OCS, cancer care providers, and software professionals were used in this formative research. Results The varied stakeholders welcomed the idea of developing an online tool to promote PA in OCS. Our formative research revealed several major barriers to regular PA including limited access to senior-friendly PA resources, lack of motivation and social support, and insufficient knowledge and skills on building safe and appropriate workout plans. This feedback was incorporated into the development of iCanFit, a mobile-enabled Web application, designed specifically for OCS. The iCanFit online tools allow users to locate PA resources, set and track goals for PA, network with peer OCS in a secure online space, and receive practical and evidence-informed healthy tips. Conclusions Our mixed-method formative research led to the design of iCanFit protocol to promote PA and well-being of OCS. The involvement of stakeholders is critical in the planning and design of the mobile application in order to enhance program relevance, appeal, and match with the needs of target users. PMID:23612053

  17. 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

  18. 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

  19. 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

  20. 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,…

  1. The effect of exposure duration on the biological activity of mobile telephony radiation.

    PubMed

    Panagopoulos, Dimitris J; Margaritis, Lukas H

    2010-06-17

    In the present experiments we studied the effects of different durations of a single (continuous), daily exposure, ranging from 1 min up to 21 min, to the two established systems of digital mobile telephony radiation that are commonly used in Europe, viz. GSM 900 MHz (Global System for Mobile telecommunications) and DCS 1800 MHz (Digital Cellular System-referred to also as GSM 1800 MHz), on a well-tested biological model, the reproductive capacity of the insect Drosophila melanogaster. The insects were exposed to each type of radiation at an intensity of about 10 microW/cm(2), corresponding to a distance of 20 or 30 cm from the antenna of a DCS 1800 or a GSM 900 mobile phone handset, respectively. At these distances the bioactivity of mobile telephony radiation was found to be at a maximum due to the existence of a "window" of increased bioactivity around this value, as we have shown recently [1-4]. The results show that the reproductive capacity decreases almost linearly with increasing exposure duration to both GSM 900 and DCS 1800 radiation, suggesting that short-term exposures to these radiations have cumulative effects on living organisms. Additionally, our results show again that GSM 900 MHz radiation is slightly more bioactive than DCS 1800 MHz radiation, at the same exposure durations and under equal radiation intensities, as shown in our previous experiments [5]. PMID:20399887

  2. 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…

  3. Protein kinase C promotes arachidonate mobilization through enhancement of CoA-independent transacylase activity in platelets.

    PubMed Central

    Breton, M; Colard, O

    1991-01-01

    A role for protein kinase C in arachidonate mobilization was demonstrated. Treatment of rat platelets with phorbol myristate acetate (PMA) or the diacylglycerol 1-oleoyl-2-acetylglycerol increased the transfer rate of arachidonate (AA) from phosphatidylcholine to phosphatidylethanolamine and stimulated AA release. The transfer dose-dependently induced by PMA was inhibited by staurosporine. Ether phospholipids were the acceptors of AA in these stimulated transfer reactions. Membrane-bound protein kinase C activity was enhanced by PMA, and this increase was inhibited by staurosporine. AA transfer between phospholipids is due to the action of polyunsaturated-fatty-acid-specific transacylases. For this purpose, transacylase activities were assayed in cell-free systems from PMA-treated platelets. We observed that the CoA-independent transacylase activity was modulated in parallel to AA transfer as a function of PMA concentration. Taken together, the data show that protein kinase C activation might promote the mobilization of AA in platelets through the enhancement of CoA-independent transacylase activity. PMID:1741761

  4. Electrophoretic assay of specific estrogen receptors: a contribution to methodology.

    PubMed

    van Netten, J P; Algard, F T; Montessori, G; Weare, B

    1977-11-01

    Experimental evidence is presented that supports the use of the cold agar-gel electrophoretic method for the clinical quantitation of specific estrogen-binding protein present in some human mammary carcinomas. It is necessary to dilute tumor extracts to avoid interference by serum-borne, non-relevant hormone-binding proteins such as albumin, which migrates to the same anodal region as does the binding protein. Dilution to 2.5 mg or less of total protein per milliliter circumvents such interference while still permitting reliable quantitation of the binding protein. Seventy-two mammary carcinomas were compared for binding-protein content by both the cold agar-gel electrophoresis and a single-point dextran-coated charcoal assay. The correlation coefficient (0.96) indicated excellent agreement between results by the two methods. In addition results are presented which indicate that the preparation of tumor extracts for electrophoresis does not require the use of an ultracentrifuge. PMID:912871

  5. 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.

  6. 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.

  7. Studies on phytochrome. Some properties of electrophoretically pure phytochrome

    PubMed Central

    Walker, T. S.; Bailey, J. L.

    1970-01-01

    1. Phytochrome was purified from etiolated oat (Avena sativa) seedlings either by gel-filtration chromatography and ion-exchange chromatography or by gel-filtration chromatography and calcium phosphate chromatography. Differences were observed in the spectral properties of phytochrome isolated by the two methods. 2. Electrophoresis of pure phytochrome at pH values between 9.0 and 6.0 showed the tendency of phytochrome to form different molecular species. Studies in the ultracentrifuge did not show a corresponding change in the sedimentation coefficient with the change in pH. 3. Tryptic digestion of electrophoretically pure phytochrome gave 17 peptides and a photoactive core. The amino acid composition of the core is reported and compared with the analysis of whole phytochrome. 4. Some properties of phytochrome isolated from Pisum sativum are compared with those of phytochrome from A. sativa. 5. The properties of phytochrome purified by other workers are compared with our findings. ImagesFig. 4. PMID:5499974

  8. 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.

  9. Formation of diamond nanoparticle thin films by electrophoretic deposition

    NASA Astrophysics Data System (ADS)

    Goto, Yosuke; Ohishi, Fujio; Tanaka, Kuniaki; Usui, Hiroaki

    2016-03-01

    Thin films of diamond nanoparticles were prepared by electrophoretic deposition (EPD) using 0.5 wt % dispersions in water, ethanol, and 2-propanol. The film growth rate increased with increasing voltage applied to the electrodes. However, an excessive increase in voltage caused the degradation of film morphology. The optimum voltage was 4 V with an electrode separation of 5 mm. The film growth rate was higher in organic solvents than in water. The deposited film had a smooth surface with an average surface roughness comparable to the size of primary particles of the source material. It is notable that the EPD films had a considerably higher physical stability than spin-coated and cast films. The stability was further improved by thermally annealing the films. IR analysis revealed that the diamond nanoparticles have carboxy and amino groups on their surfaces. It is considered that the stability of the EPD films originate from a chemical reaction between these functional groups.

  10. 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

  11. 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

  12. Activation of two different receptors mobilizes calcium from distinct stores in Xenopus oocytes

    SciTech Connect

    Shapira, H.; Lupu-Meiri, M.; Gershengorn, M.C.; Oron, Y. )

    1990-06-01

    Acetylcholine (ACh) and thyrotropin-releasing hormone (TRH) utilize inositol 1,4,5-trisphosphate (IP3) as a second messenger and evoke independent depolarizing membrane electrical responses accompanied by characteristic {sup 45}Ca efflux profiles in Xenopus laevis oocytes injected with GH3 pituitary cell mRNA. To determine whether this could be accounted for by mobilization of calcium from functionally separate stores, we measured simultaneously {sup 45}Ca efflux and membrane electrical responses to ACh and TRH in single oocytes. We found that depletion of ACh-sensitive calcium store did not affect the membrane electrical response to TRH and the TRH-evoked {sup 45}Ca efflux. Our data suggest that ACh and TRH mobilize calcium from distinct cellular stores in the oocyte. This is the first demonstration in a single cell of strict subcellular compartmentalization of calcium stores coupled to two different populations of cell membrane receptors that utilize the same second messenger.

  13. 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

  14. 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

  15. Sizing Large Proteins and Protein Complexes by Electrospray Ionization Mass Spectrometry and Ion Mobility

    PubMed Central

    Kaddis, Catherine S.; Lomeli, Shirley H.; Yin, Sheng; Berhane, Beniam; Apostol, Marcin I.; Kickhoefer, Valerie A.; Rome, Leonard H.; Loo, Joseph A.

    2009-01-01

    Mass spectrometry (MS) and ion mobility with electrospray ionization (ESI) have the capability to measure and detect large noncovalent protein-ligand and protein-protein complexes. Using an ion mobility method termed GEMMA (Gas-Phase Electrophoretic Mobility Molecular Analysis), protein particles representing a range of sizes can be separated by their electrophoretic mobility in air. Highly charged particles produced from a protein complex solution using electrospray can be manipulated to produce singly charged ions which can be separated and quantified by their electrophoretic mobility. Results from ESI-GEMMA analysis from our laboratory and others were compared to other experimental and theoretically determined parameters, such as molecular mass and cryoelectron microscopy and x-ray crystal structure dimensions. There is a strong correlation between the electrophoretic mobility diameter determined from GEMMA analysis and the molecular mass for protein complexes up to 12 MDa, including the 93 kDa enolase dimer, the 480 kDa ferritin 24-mer complex, the 4.6 MDa cowpea chlorotic mottle virus (CCMV), and the 9 MDa MVP-vault assembly. ESI-GEMMA is used to differentiate a number of similarly sized vault complexes that are composed of different N-terminal protein tags on the MVP subunit. The average effective density of the proteins and protein complexes studied was 0.6 g/cm3. Moreover, there is evidence that proteins and protein complexes collapse or become more compact in the gas phase in the absence of water. PMID:17434746

  16. 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).

  17. 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

  18. 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. PMID:22278771

  19. A study of electrically active traps in AlGaN/GaN high electron mobility transistor

    NASA Astrophysics Data System (ADS)

    Yang, Jie; Cui, Sharon; Ma, T. P.; Hung, Ting-Hsiang; Nath, Digbijoy; Krishnamoorthy, Sriram; Rajan, Siddharth

    2013-10-01

    We have studied electron conduction mechanisms and the associated roles of the electrically active traps in the AlGaN layer of an AlGaN/GaN high electron mobility transistor structure. By fitting the temperature dependent I-V (Current-Voltage) curves to the Frenkel-Poole theory, we have identified two discrete trap energy levels. Multiple traces of I-V measurements and constant-current injection experiment all confirm that the main role of the traps in the AlGaN layer is to enhance the current flowing through the AlGaN barrier by trap-assisted electron conduction without causing electron trapping.

  20. Multimedia authoring and synchronization within ActiveM3: a system for composing active e-mail messages as subtypes of mobile agents

    NASA Astrophysics Data System (ADS)

    Schirmer, Juergen; Hayn, Ralf

    1998-09-01

    Multimedia electronic mail and active electronic mail are very well known concepts. Multimedia electronic mail is concerned with the transmission of multimedia information like images, audio and video objects within email. Moreover, active email (or enhanced email) incorporates programs in ordinary electronic mail. The active email message automatically executes at the email receiver's site and, for instance, orchestrates the presentation of the multimedia information. This kind of message can be regarded as a subtype of a mobile agent which as a user interface and which gets into contact with the enduser. Based on a realized prototype ActiveM3, the related concepts for multimedia authoring and synchronization within the active email approach are introduced in this article.

  1. 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.

  2. 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

  3. Sedimentation of macroscopic rigid knots and its relation to gel electrophoretic mobility of DNA knots.

    PubMed

    Weber, Cédric; Carlen, Mathias; Dietler, Giovanni; Rawdon, Eric J; Stasiak, Andrzej

    2013-01-01

    We address the general question of the extent to which the hydrodynamic behaviour of microscopic freely fluctuating objects can be reproduced by macrosopic rigid objects. In particular, we compare the sedimentation speeds of knotted DNA molecules undergoing gel electrophoresis to the sedimentation speeds of rigid stereolithographic models of ideal knots in both water and silicon oil. We find that the sedimentation speeds grow roughly linearly with the average crossing number of the ideal knot configurations, and that the correlation is stronger within classes of knots. This is consistent with previous observations with DNA knots in gel electrophoresis. PMID:23346349

  4. Sedimentation of macroscopic rigid knots and its relation to gel electrophoretic mobility of DNA knots

    PubMed Central

    Weber, Cédric; Carlen, Mathias; Dietler, Giovanni; Rawdon, Eric J.; Stasiak, Andrzej

    2013-01-01

    We address the general question of the extent to which the hydrodynamic behaviour of microscopic freely fluctuating objects can be reproduced by macrosopic rigid objects. In particular, we compare the sedimentation speeds of knotted DNA molecules undergoing gel electrophoresis to the sedimentation speeds of rigid stereolithographic models of ideal knots in both water and silicon oil. We find that the sedimentation speeds grow roughly linearly with the average crossing number of the ideal knot configurations, and that the correlation is stronger within classes of knots. This is consistent with previous observations with DNA knots in gel electrophoresis. PMID:23346349

  5. Overcharging in Biological Systems: Reversal of Electrophoretic Mobility of Aqueous Polyaspartate by Multivalent Cations

    NASA Astrophysics Data System (ADS)

    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.

  6. 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.

  7. 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.

  8. 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. PMID:26003417

  9. 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.

  10. Theory of activated glassy relaxation, mobility gradients, surface diffusion, and vitrification in free standing thin films.

    PubMed

    Mirigian, Stephen; Schweizer, Kenneth S

    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. PMID:26723700

  11. Theory of activated glassy relaxation, mobility gradients, surface diffusion, and vitrification in free standing thin films

    NASA Astrophysics Data System (ADS)

    Mirigian, Stephen; Schweizer, Kenneth S.

    2015-12-01

    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.

  12. Purification and variability in thrombin-like activity of Bothrops atrox venom from different geographic regions.

    PubMed

    Cavinato, R A; Remold, H; Kipnis, T L

    1998-02-01

    Bothrops atrox snake venoms from two different Amazon regions, i.e., Manaus, AM (3 degrees 0.6'40"S; 60 degrees 0.1'6.0"W) and Tucurui, PA (3 degrees 0.42'30"S; 49 degrees 0.41'45"W), were analyzed with respect to the thrombin-like activity component by elution profile on gel-filtration and reverse phase HPLC chromatography, electrophoretic mobility on SDS-PAGE, and enzymatic activity on fibrinogen. Despite some individual discrepancies among venom specimens, the thrombin-like activity present in the Manaus pool was eluted earlier compared with the Tucurui pool but its enzymatic specific activity on thrombin was lower (s.a. = 6.0) than that observed in the Tucurui pool (s.a. = 134.0). However, the electrophoretic mobilities of the pools were similar, with most protein bands being concentrated around three main regions, i.e., protein bands with an apparent mr of 100 kDa, of 38-37 kDa and 30 kDa. However, no significant differences were observed in amidolytic activity on the synthetic substrate Tos-Gly-Pro-Arg-pNa, and there was no correlation between thrombin-like and amidolytic activities. A 32 kDa protein endowed with thrombin-like activity and specific activity of 2444 recognized and neutralized by horse anti-B. atrox antivenom, was purified by the successive use of gel filtration, electrofocusing and reverse phase HPLC. PMID:9620574

  13. A study on the gate voltage dependence of the activation energy in Meyer-Neldel rule for charge mobility in pentacene OTFTs

    SciTech Connect

    Petrosino, Mario; Rubino, Alfredo; Miscioscia, Riccardo; Girolamo del Mauro, Anna de; Rega, Romina; Cerri, Valerio; Minarini, Carla

    2010-06-02

    A temperature analysis of the OTFT having pentacene as channel semiconductor and PMMA as gate dielectric has been performed. The experimental results have been studied by extracting the field-effect mobility of the TFTs and relating it to the sample's temperature. We have found the mobility to follow the Meyer-Neldel rule. This behavior can be considered imputable to the channel carrier hopping. The gate voltage effect on the thermal activation energy for the mobility and the asymptotic parameter has been also taken into account.

  14. Design and test of a hybrid foot force sensing and GPS system for richer user mobility activity recognition.

    PubMed

    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

  15. 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

  16. 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.

  17. 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.

  18. 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.

  19. A model for electrophoretic transport of charged particles through membrane before steady state

    NASA Astrophysics Data System (ADS)

    de Souza, Tatiana Miranda; Fragoso, Viviane Muniz da Silva; Cruz, Frederico Alan de Oliveira

    2015-12-01

    In this paper, we are presenting a model for electrophoretic motion of a charged particle through the membrane before it reaches the steady state, based on concepts of Physics. Some results from analysis of the model are discussed.

  20. 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

  1. 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

  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. Open source simulation tool for electrophoretic stacking, focusing, and separation.

    PubMed

    Bercovici, Moran; Lele, Sanjiva K; Santiago, Juan G

    2009-02-01

    We present the development, formulation, and performance of a new simulation tool for electrophoretic preconcentration and separation processes such as capillary electrophoresis, isotachophoresis, and field amplified sample stacking. The code solves the one-dimensional transient advection-diffusion equations for multiple multivalent weak electrolytes (including ampholytes) and includes a model for pressure-driven flow and Taylor-Aris dispersion. The code uses a new approach for the discretization of the equations, consisting of a high resolution compact scheme which is combined with an adaptive grid algorithm. We show that this combination allows for accurate resolution of sharp concentration gradients at high electric fields, while at the same time significantly reducing the computational time. We demonstrate smooth, stable, and accurate solutions at current densities as high as 5000A/m(2) using only 300 grid points, and a 75-fold reduction in computational time compared with equivalent uniform grid techniques. The code is available as an open source for free at http://microfluidics.stanford.edu. PMID:19124132

  4. 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.

  5. 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

  6. Interfacial bond strength of electrophoretically deposited hydroxyapatite coatings on metals.

    PubMed

    Wei, M; Ruys, A J; Swain, M V; Kim, S H; Milthorpe, B K; Sorrell, C C

    1999-07-01

    Hydroxyapatite (HAp) coatings were deposited onto substrates of metal biomaterials (Ti, Ti6Al4V, and 316L stainless steel) by electrophoretic deposition (EPD). Only ultra-high surface area HAp powder, prepared by the metathesis method 10Ca(NO3)2 + 6(NH4)2HPO4 + 8NH4OH), could produce dense coatings when sintered at 875-1000degreesC. Single EPD coatings cracked during sintering owing to the 15-18% sintering shrinkage, but the HAp did not decompose. The use of dual coatings (coat, sinter, coat, sinter) resolved the cracking problem. Scanning electron microscopy/energy dispersive spectroscopy (SEM/EDS) inspection revealed that the second coating filled in the "valleys" in the cracks of the first coating. The interfacial shear strength of the dual coatings was found, by ASTM F1044-87, to be approximately 12 MPa on a titanium substrate and approximately 22 MPa on 316L stainless steel, comparing quite favorably with the 34 MPa benchmark (the shear strength of bovine cortical bone was found to be 34 MPa). Stainless steel gave the better result since -316L (20.5 microm mK(-1)) > alpha-HAp (approximately 14 microm mK(-1)), resulting in residual compressive stresses in the coating, whereas alpha-titanium (approximately 10.3 microm mK(-1)) < alpha-HAp, resulting in residual tensile stresses in the coating. PMID:15348125

  7. Electrophoretic assembly of organic molecules and composites for electrochemical supercapacitors.

    PubMed

    Su, Y; Zhitomirsky, I

    2013-02-15

    Electrophoretic deposition (EPD) method has been developed for the fabrication of 1-pyrenebutyric acid (PBH) films from aqueous solutions. The films can be deposited at constant voltage or potentiodynamic conditions. The method allowed the formation of 0.1-2 μm thick films, containing needle-shape PBH particles. The deposition mechanism involved the electrophoresis, pH decrease at the anode surface, charge neutralization and formation of insoluble PBH films. The film morphology and shape of the PBH particles are controlled by the π-π stacking mechanism of the polyaromatic PBH molecules. The important finding was the possibility of controlled EPD of multiwalled carbon nanotubes (MWCNTs) using PBH as a charging, dispersing and film forming agent. It was found that at low voltages or low PBH concentrations the deposits contained mainly MWCNT. The increase in the deposition voltage or/and PBH concentration resulted in co-deposition of MWCNT and needle-shape PBH particles. The new approach to the deposition of MWCNT was used for the fabrication of composite MnO(2)-MWCNT films for electrodes of electrochemical supercapacitors, which showed a specific capacitance of 250 F g(-1). The EPD method developed in this investigation paves the way for the deposition of other small organic molecules and composites and their applications in new materials and devices, utilizing functional properties of the organic molecules, CNT, and other advanced materials. PMID:23141761

  8. Electrophoretic nanotechnology of composite electrodes for electrochemical supercapacitors.

    PubMed

    Su, Y; Zhitomirsky, I

    2013-02-14

    The electrophoretic deposition (EPD) method has been developed for the fabrication of MnO(2)-multiwalled carbon nanotube (MWCNT) films for application in electrochemical supercapacitors (ESs). For MWCNT applications, which depend on electrical conductivity, it is challenging to achieve dispersion and EPD of pristine MWCNT and avoid defects due to chemical treatment or functionalization. An important finding was the possibility of efficient dispersion and controlled EPD of MWCNT using calconcarboxylic acid (CCA). Moreover, the use of CCA allowed efficient dispersion of MnO(2) in concentrated suspensions and EPD of MnO(2) films. The comparison of the experimental data for chromotrope FB (CFB) and CCA and chemical structures of the molecules provided insight into the mechanism of CCA adsorption on MnO(2). The fabrication of stable suspensions of MnO(2) nanoparticles containing MWCNT, and controlled codeposition of both materials is a crucial aspect in the EPD of composites. The new approach was based on the use of CCA as a charging and dispersing agent for EPD of MnO(2) nanoparticles and MWCNT. The deposition yield measurements at various experimental conditions and Fourier transform infrared spectroscopy data, coupled with results of electron microscopy, thermogravimetric, and differential thermal analysis provided evidence of the formation of MnO(2)-MWCNT composites. The electrochemical testing results and impedance spectroscopy data showed good capacitive behavior of the composite films and the beneficial effect of MWCNTs. PMID:22662969

  9. 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.

  10. Improvement of electrophoretic enantioseparation of amlodipine by polybrene.

    PubMed

    Zandkarimi, Majid; Shafaati, Alireza; Foroutan, Sayyed Mohsen; A Lucy, Charles

    2012-01-01

    In chiral and non-chiral electrophoretic resolution of basic drugs, adsorption of analytes to negatively charged capillary wall could lead to poor repeatability of migration time and peak area. In addition, chiral resolutions of basic drugs are commonly performed in low pH buffers. Therefore, longer analysis time due to suppression of electroosmotic flow (EOF) is another dilemma. In this work the improvement effect of polybrene (PB), a cationic polymer, on chiral separation of a model basic drug, amlodipine (AML), was investigated. PB both as a semi-permanent coating agent and as an additive in the running buffer was utilized. Better results were obtained with PB as a buffer additive. Compare to untreated bare silica without using PB in running buffer, addition of 0.0005% PB buffer decreased analysis time downed to 3 folds; efficiency improved up to 5 folds; limit of detection (LOD) and limit of quantification (LOQ) downed to 8 folds and within-day migration time and peak area repeatabilities, in terms of relative standard deviations (RSD) downed to 5 and 20 folds, respectively. PMID:25317194

  11. Improvement of Electrophoretic Enantioseparation of Amlodipine by Polybrene

    PubMed Central

    Zandkarimi, Majid; Shafaati, Alireza; Foroutan, Sayyed Mohsen; A. Lucy, Charles

    2012-01-01

    In chiral and non-chiral electrophoretic resolution of basic drugs, adsorption of analytes to negatively charged capillary wall could lead to poor repeatability of migration time and peak area. In addition, chiral resolutions of basic drugs are commonly performed in low pH buffers. Therefore, longer analysis time due to suppression of electroosmotic flow (EOF) is another dilemma. In this work the improvement effect of polybrene (PB), a cationic polymer, on chiral separation of a model basic drug, amlodipine (AML), was investigated. PB both as a semi-permanent coating agent and as an additive in the running buffer was utilized. Better results were obtained with PB as a buffer additive. Compare to untreated bare silica without using PB in running buffer, addition of 0.0005% PB buffer decreased analysis time downed to 3 folds; efficiency improved up to 5 folds; limit of detection (LOD) and limit of quantification (LOQ) downed to 8 folds and within-day migration time and peak area repeatabilities, in terms of relative standard deviations (RSD) downed to 5 and 20 folds, respectively. PMID:25317194

  12. Fabrication of Electrophoretic Display Driven by Membrane Switch Array

    NASA Astrophysics Data System (ADS)

    Senda, Kazuo; Usui, Hiroaki

    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.

  13. 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.

  14. 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

  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. PMID:26878711

  16. 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

  17. 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…

  18. Vector-host-parasite inter-relationships in leishmaniasis. IV. Electrophoretic studies on proteins of four vertebrate bloods with and without Leishmania infantum or L. major.

    PubMed

    Daba, S; Mansour, N S; Youssef, F G; Shanbaky, N M; el Sawaf, B M

    1997-12-01

    Fifty five protein bands with relative mobilities of 8,954 to 245,471 kilo Daltons (kD) were electrophoretically separated from 12 feeding media of blood from 4 natural vertebrate hosts of Phlebotomus langeroni. The feeding media included human, dog (Canis familiaris), rat (Rattus rattus) and turkey (Melagris gallopava) bloods without or with Leishmania infantum or L. major promastigotes. Protein bands were identical among the feeding media of one host's blood but varied in number (24-28 bands) and relative mobilities among the various hosts' blood. Some protein fractions were common among the various hosts blood, others were only present in two or three hosts' blood and some were restricted to one host blood and were unique for each host. This study provides data which may help in understanding why blood from different natural hosts may variably influence the life cycle of Leishmania parasite in the sand fly gut. PMID:9425823

  19. 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

  20. Involvement of Nitric Oxide on Calcium Mobilization and Arachidonic Acid Pathway Activation during Platelet Aggregation with different aggregating agonists.

    PubMed

    Banerjee, Debipriya; Mazumder, Sahana; Kumar Sinha, Asru

    2016-03-01

    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 Ca(2+) 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 [Ca(2+)] in nM ranges. In contrast, the pre-treatment of washed PRP with aspirin increased platelet NO level and inhibited the Ca(2+) mobilization and TXA2 synthesis. These results indicated that the aggregation of platelets by different aggregating agonists was caused by the cytosolic Ca(2+) mobilization due to the inhibition of NOS. PMID:27127451

  1. 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

  2. Effect of micelles and mixed micelles on efficiency and selectivity of antibiotic-based capillary electrophoretic enantioseparations

    SciTech Connect

    Rundlett, K.L.; Armstrong, D.W.

    1995-07-01

    Vancomycin (an oligophenolic, glycopeptide, macrocyclic antibiotic) has been shown to be a superb chiral selector for anionic and neutral compounds. It was found that adding sodium dodecyl sulfate to the run buffer increased efficiency by over 1 order of magnitude, decreased analysis times, and reversed the elution order of the enantiomers. This allows for control of the retention order as well as the resolution of enantiomers in complex mixtures in a single run. A mechanism is proposed which explains all of the observed effects and is verified experimentally. Since vancomycin is present in both the micelle and in free solution, previously proposed micelle-selector models are, at best, limiting cases. A general equation is derived which can be used to describe all possible interactions, including those with the capillary wall, if needed. Also, it is shown that electrophoretic mobilities and not migration times must be used to calculate binding constants of a solute to the micelle, the chiral selector, or both. Furthermore, it is shown that a neutral marker molecule cannot be used to accurately correct mobilities that have been altered due to changes in solution viscosity. While this work utilizes the practical vancomycin-micelle system, the general conclusions and theory apply to most other analogous CE systems as well. 48 refs., 4 figs., 5 tabs.

  3. Determination of sulfonylureas in cereal samples with electrophoretic method using ionic liquid with dispersed carbon nanotubes as electrophoretic buffer.

    PubMed

    Springer, Valeria H; Aprile, Francisco; Lista, Adriana G

    2014-01-15

    A capillary electrophoresis method to determine four sulfonylureas in grain samples was developed using 10mM of 1-butyl-3-methyl imidazolium tetrafluoroborate (bminBF4) as electrophoretic buffer solution. 2mgL(-1) of Surfactant Coated-Single Wall-Carbon Nanotubes (SC-SWCNTs) was added to the buffer solution to improve the resolution. In this way, the separation of nicosulfuron, ethoxysulfuron, sulfometuron methyl and chlorsulfuron was carried out in 16min without using organic solvents. A clean up-preconcentration procedure was done prior to inject the sample into the CE instrument, in order to achieve the established maximum residue limits (MRLs). So, the detection limits (LODs) for each analytes were between 16.8 and 26.6μgkg(-1). The relative standard deviations (RSDs) were in the range 1.9-6.7%. A recovery study using the so-called matrix matched calibration demonstrates that no matrix interferences were found throughout the determination. The recovery percentages were ranged between 80% and 113%. PMID:24054250

  4. The effects of ankle mobilization and active stretching on the difference of weight-bearing distribution, low back pain and flexibility in pronated-foots subjects

    PubMed Central

    Yoon, Ki-Seok; Park, Seong-Doo

    2013-01-01

    The purpose of this study was designed to analyze the effects mobilization and active stretching on the difference of weight-bearing distribution, low back pain, and flexibility in pronated-foot subjects. The subjects of this study were 16 chronic low back pain patients. They were randomly divided into the control and experimental group. The experimental group had used the model of ankle mobilization and calf muscle active stretching three times per week, for 4 weeks. The control group did same method without an ankle mobilization. The range of flexion and extension motion of the lumbar vertebrae and low back pain degree and difference of weight-bearing were measured before and after the experiment. The model of ankle mobilization and calf muscle stretching of pronated-foot significantly improved the range of flexion and extension motion of the vertebrae. And the visual analogue scale and distribution of weight-bearing were decreased in both of two groups. In other word, the exercise of this study showed that the model of ankle mobilization and calf muscle stretching of pronated-foot had positive effects on improving the range of flexion and extension motion of the vertebrae. The calf muscle stretching was easy and it is effective in therapy that patients by themselves and helped to recover the balance of the vertebrae to combine ankle mobilization and muscle stretching. PMID:24278874

  5. Ribosomal frameshifting and dual-target antiactivation restrict quorum-sensing–activated transfer of a mobile genetic element

    PubMed Central

    Ramsay, Joshua P.; Tester, Laura G. L.; Major, Anthony S.; Sullivan, John T.; Edgar, Christina D.; Kleffmann, Torsten; Patterson-House, Jackson R.; Hall, Drew A.; Tate, Warren P.; Hynes, Michael F.; Ronson, Clive W.

    2015-01-01

    Symbiosis islands are integrative and conjugative mobile genetic elements that convert nonsymbiotic rhizobia into nitrogen-fixing symbionts of leguminous plants. Excision of the Mesorhizobium loti symbiosis island ICEMlSymR7A is indirectly activated by quorum sensing through TraR-dependent activation of the excisionase gene rdfS. Here we show that a +1 programmed ribosomal frameshift (PRF) fuses the coding sequences of two TraR-activated genes, msi172 and msi171, producing an activator of rdfS expression named Frameshifted excision activator (FseA). Mass-spectrometry and mutational analyses indicated that the PRF occurred through +1 slippage of the tRNAphe from UUU to UUC within a conserved msi172-encoded motif. FseA activated rdfS expression in the absence of ICEMlSymR7A, suggesting that it directly activated rdfS transcription, despite being unrelated to any characterized DNA-binding proteins. Bacterial two-hybrid and gene-reporter assays demonstrated that FseA was also bound and inhibited by the ICEMlSymR7A-encoded quorum-sensing antiactivator QseM. Thus, activation of ICEMlSymR7A excision is counteracted by TraR antiactivation, ribosomal frameshifting, and FseA antiactivation. This robust suppression likely dampens the inherent biological noise present in the quorum-sensing autoinduction circuit and ensures that ICEMlSymR7A transfer only occurs in a subpopulation of cells in which both qseM expression is repressed and FseA is translated. The architecture of the ICEMlSymR7A transfer regulatory system provides an example of how a set of modular components have assembled through evolution to form a robust genetic toggle that regulates gene transcription and translation at both single-cell and cell-population levels. PMID:25787256

  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. 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.

  8. 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

  9. LYAR promotes colorectal cancer cell mobility by activating galectin-1 expression.

    PubMed

    Wu, Yupeng; Liu, Ming; 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

    2015-10-20

    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

  10. 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.

  11. 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

  12. The active gene that encodes human High Mobility Group 1 protein (HMG1) contains introns and maps to chromosome 13

    SciTech Connect

    Ferrari, S.; Finelli, P.; Rocchi, M.

    1996-07-15

    The human genome contains a large number of sequences related to the cDNA for High Mobility Group 1 protein (HMG1), which so far has hampered the cloning and mapping of the active HMG1 gene. We show that the human HMG1 gene contains introns, while the HMG1-related sequences do not and most likely are retrotransposed pseudogenes. We identified eight YACs from the ICI and CEPH libraries that contain the human HMG1 gene. The HMG1 gene is similar in structure to the previously characterized murine homologue and maps to human chromosome 13 and q12, as determined by in situ hybridization. The mouse Hmg1 gene maps to the telomeric region of murine Chromosome 5, which is syntenic to the human 13q12 band. 18 refs., 3 figs.

  13. 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

  14. Electrophoretic capture and detection of nanoparticles at the opening of a membrane pore using scanning electrochemical microscopy.

    PubMed

    Lee, Sungwon; Zhang, Yanhui; White, Henry S; Harrell, C Chad; Martin, Charles R

    2004-10-15

    Stochastic electrophoretic capture of individual nanometer-scale particles at the small opening of a conically shaped nanopore in a synthetic membrane is described. Particle capture is sensed using a scanning electrochemical microscope (SECM) to measure the decrease in the transport rate of a redox-active molecule through the pore. The SECM tip is positioned at the larger backside opening of pore and used to amperometrically monitor the transport rate prior, during, and after particle capture. Following capture, the particle is released by electrophoretically driving it out of the pore opening and back into the solution. The capture and release method is demonstrated by detection of charged polystyrene spheres (43-150-nm diameter) using a polycarbonate membrane with conically shaped pores, the small opening of the pore having a diameter of 60 nm. The inverse of the time to capture polystyrene spheres increases with particle concentration over the range 10(8)-10(10) particles/mL. Selective detection based on nanoparticle charge and size is also demonstrated. A quantitative theoretical description of the rate of particle capture is presented, and the physical mechanism of particle capture, based on the balance of electrostatic and entropic forces, is considered. PMID:15481960

  15. 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

  16. 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

  17. 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

  18. 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.

  19. High-mobility group box 1 activates integrin-dependent homing of endothelial progenitor cells.

    PubMed

    Chavakis, Emmanouil; Hain, Andreas; Vinci, Maria; Carmona, Guillaume; Bianchi, Marco E; Vajkoczy, Peter; Zeiher, Andreas M; Chavakis, Triantafyllos; Dimmeler, Stefanie

    2007-02-01

    Endothelial progenitor cells (EPCs) are recruited to ischemic regions and improve neovascularization. Integrins contribute to EPC homing. High-mobility group box 1 (HMGB1) is a nuclear protein that is released extracellularly on cell necrosis and tissue damage, eliciting a proinflammatory response and stimulating tissue repair. In the present study, we investigated the effects of HMGB1 on EPC homing. EPCs express the HMGB1 receptors RAGE (receptor for advanced glycation end products) and TLR2 (Toll-like receptor 2). EPC migration was stimulated by HMGB1 in a RAGE-dependent manner. In addition, the HMGB1-induced migration of EPCs on fibronectin and fibrinogen was significantly inhibited by antibodies against beta1 and beta2 integrins, respectively. Short-term prestimulation of EPCs with HMGB1 also increased EPC adhesion to endothelial cell monolayers, and this effect was blocked by antibodies to beta2 integrins or RAGE. HMGB1 increased EPC adhesion to the immobilized integrin ligands intercellular adhesion molecule-1 and fibronectin in a RAGE-dependent manner. Strikingly, HMGB1 rapidly increased integrin affinity and induced integrin polarization. Using intravital microscopy in a tumor model of neovascularization, prestimulation of EPCs with HMGB1 enhanced the initial in vivo adhesion of EPCs to microvessels and the recruitment of EPCs in the tumor tissue. In addition, prestimulation of EPCs with HMGB1 increased the homing of EPCs to ischemic muscles. In conclusion, these data represent a link between HMGB1 and integrin functions of EPCs and demonstrate that HMGB1 stimulates EPC homing to ischemic tissues. These results may provide a platform for the development of novel therapeutic approaches to improve EPC homing. PMID:17218606

  20. Reprogramming somatic cells into iPS cells activates LINE-1 retroelement mobility

    PubMed Central

    Wissing, Silke; Muñoz-Lopez, Martin; Macia, Angela; Yang, Zhiyuan; Montano, Mauricio; Collins, William; Garcia-Perez, Jose Luis; Moran, John V.; Greene, Warner C.

    2012-01-01

    Long interspersed element-1 (LINE-1 or L1) retrotransposons account for nearly 17% of human genomic DNA and represent a major evolutionary force that has reshaped the structure and function of the human genome. However, questions remain concerning both the frequency and the developmental timing of L1 retrotransposition in vivo and whether the mobility of these retroelements commonly results in insertional and post-insertional mechanisms of genomic injury. Cells exhibiting high rates of L1 retrotransposition might be especially at risk for such injury. We assessed L1 mRNA expression and L1 retrotransposition in two biologically relevant cell types, human embryonic stem cells (hESCs) and induced pluripotent stem cells (iPSCs), as well as in control parental human dermal fibroblasts (HDFs). Full-length L1 mRNA and the L1 open reading frame 1-encoded protein (ORF1p) were readily detected in hESCs and iPSCs, but not in HDFs. Sequencing analysis proved the expression of human-specific L1 element mRNAs in iPSCs. Bisulfite sequencing revealed that the increased L1 expression observed in iPSCs correlates with an overall decrease in CpG methylation in the L1 promoter region. Finally, retrotransposition of an engineered human L1 element was ∼10-fold more efficient in iPSCs than in parental HDFs. These findings indicate that somatic cell reprogramming is associated with marked increases in L1 expression and perhaps increases in endogenous L1 retrotransposition, which could potentially impact the genomic integrity of the resultant iPSCs. PMID:21989055

  1. Increasing Physical Activity Efficiently: An Experimental Pilot Study of a Website and Mobile Phone Intervention

    PubMed Central

    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

  2. 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

  3. 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

  4. 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

  5. Capillary electrophoretic separation of poly(ethylene glycol)-modified granulocyte-colony stimulating factor.

    PubMed

    Lee, Kyung Soo; Na, Dong Hee

    2010-03-01

    We evaluated the utility of capillary electrophoretic methods for analyzing poly(ethylene glycol) (PEG)-modified granulocyte-colony stimulating factor (G-CSF), a long-acting form of GCSF for the treatment of cancer therapy-induced neutropenia. Low- and high-molecularweight PEG-G-CSF conjugates prepared with aldehyde-activated PEG-5K and PEG-20K were separated by high-performance size-exclusion chromatography (HP-SEC), capillary zone electrophoresis (CZE), and sodium dodecyl sulfate-capillary gel electrophoresis (SDS-CGE). HPSEC showed low resolution for separating mono- and di-PEG-G-CSFs. SDS-CGE had higher resolution, but required a long analysis and had low peak efficiency. CZE could successfully separate both PEG-5K- and PEG-20K-conjugated G-CSFs with a running time of 20 min and high peak efficiency. In conclusion, CZE was better than SDS-CGE for separating PEG-G-CSF conjugates and will be useful for PEGylation studies, such as reaction monitoring for optimization of the PEGylation reaction, and purity and stability tests of PEG-G-CSF. PMID:20361316

  6. High mobility group protein 2 functionally interacts with the POU domains of octamer transcription factors.

    PubMed Central

    Zwilling, S; König, H; Wirth, T

    1995-01-01

    The octamer transcription factors Oct1 and Oct2 are involved in the transcriptional regulation of both lymphoid-specific and ubiquitously expressed genes. Their activity depends critically on their interaction with distinct cellular cofactors. Therefore, we have isolated cDNAs encoding proteins that physically interact with Oct2. Here we describe the analysis of one such clone, representing the murine homologue of high mobility group (HMG) protein 2. We have mapped the interaction domains for both proteins and have shown that HMG2 and Oct2 interact via their HMG domains and POU homeodomains, respectively. This interaction is not restricted to Oct2, as other members of the octamer transcription factor family like Oct1 and Oct6 also interact with HMG2. The interaction with HMG2 results in a marked increase in the sequence-specific DNA binding activity of the Oct proteins. Interestingly, the HMG2 protein is not present in the protein-DNA complex detected by an electrophoretic mobility shift assay. The Oct and HMG2 proteins also interact in vivo. A chimeric protein, in which the strong transactivation domain of VP16 was fused directly to the HMG domains of HMG2, stimulated the activity of an octamer-dependent reporter construct upon cotransfection. Furthermore, the expression of antisense RNA for HMG2 specifically reduces octamer-dependent transcription. These results suggest that one of the functions of HMG2 is to support the octamer transcription factors in their role as transcriptional activators. Images PMID:7720710

  7. [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.

  8. 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…

  9. Arsenic mobility in the amended mine tailings and its impact on soil enzyme activity.

    PubMed

    Koo, Namin; Lee, Sang-Hwan; Kim, Jeong-Gyu

    2012-06-01

    The objectives of this study were to elucidate the effects of soil amendments [Ferrous sulfate (Fe(II)), red mud, Fe(II) with calcium carbonate (Fe(II)/L) or red mud (RM/F), zero-valent iron (ZVI), furnace slag, spent mushroom waste and by-product fertilizer] on arsenic (As) stabilization and to establish relationships between soil properties, As fractions and soil enzyme activities in amended As-rich gold mine tailings (Kangwon and Keumkey). Following the application of amendments, a sequential extraction test and evaluation of the soil enzyme activities (dehydrogenase and β-glucosidase) were conducted. Weak and negative relationships were observed between water-soluble As fractions (As(WS)) and oxalate extractable iron, while As(WS) was mainly affected by dissolved organic carbon in alkaline tailings sample (Kangwon) and by soil pH in acidic tailings sample (Keumkey). The soil enzyme activities in both tailings were mainly associated with As(WS). Principal component and multiple regression analyses confirmed that As(WS) was the most important factor to soil enzyme activities. However, with some of the treatments in Keumkey, contrary results were observed due to increased water-soluble heavy metals and carbon sources. In conclusion, our results suggest that to simultaneously achieve decreased As(WS) and increased soil enzyme activities, Kangwon tailings should be amended with Fe(II), Fe(II)/L or ZVI, while only ZVI or RM/F would be suitable for Keumkey tailings. Despite the limitations of specific soil samples, this result can be expected to provide useful information on developing a successful remediation strategy of As-contaminated soils. PMID:21850414

  10. Fabrication and kinetics study of nano-Al/NiO thermite film by electrophoretic deposition.

    PubMed

    Zhang, Daixiong; Li, Xueming

    2015-05-21

    Nano-Al/NiO thermites were successfully prepared as film by electrophoretic deposition (EPD). For the key issue of this EPD, a mixture solvent of ethanol-acetylacetone (1:1 in volume) containing 0.00025 M nitric acid was proved to be a suitable dispersion system for EPD. The kinetics of electrophoretic deposition for both nano-Al and nano-NiO were investigated; the linear relation between deposition weight and deposition time in short time and parabolic relation in prolonged time were observed in both EPDs. The critical transition time between linear deposition kinetics and parabolic deposition kinetics for nano-Al and nano-NiO were 20 and 10 min, respectively. The theoretical calculation of the kinetics of electrophoretic deposition revealed that the equivalence ratio of nano-Al/NiO thermites film would be affected by the behavior of electrophoretic deposition for nano-Al and nano-NiO. The equivalence ratio remained steady when the linear deposition kinetics dominated for both nano-Al and nano-NiO. The equivalence ratio would change with deposition time when deposition kinetics for nano-NiO changed into parabolic kinetics dominated after 10 min. Therefore, the rule was suggested to be suitable for other EPD of bicomposites. We also studied thermodynamic properties of electrophoretic nano-Al/NiO thermites film as well as combustion performance. PMID:25950271

  11. 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

  12. 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}.

  13. 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. PMID:23454664

  14. 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. PMID:25571580

  15. Mobility, strength, and fitness after a graded activity program for patients with subacute low back pain. A randomized prospective clinical study with a behavioral therapy approach.

    PubMed

    Lindström, I; Ohlund, C; Eek, C; Wallin, L; Peterson, L E; Nachemson, A

    1992-06-01

    Patients with nonspecific mechanical low back pain (n = 103), examined by an orthopaedic surgeon and a social worker, were randomized to an activity group (n = 51) and a control group (n = 52). Patients with defined orthopaedic, medical, or psychiatric diagnoses were excluded before randomization. No patients were excluded due to place of birth or difficulties in speaking or understanding the Swedish language. The purpose of the study was to compare mobility, strength and fitness after traditional care and after traditional care plus a graded activity program with a behavioral therapy approach. A graded activity program, with a behavioral therapy approach was given under the guidance of a physical therapist. The endpoint of the graded activity program was return to work. This program significantly increased mobility, strength, and fitness more than could be explained by only a time recovery effect, especially in males. The patients in the activity group returned to work earlier than did the patients in the control group. Spinal rotation, abdominal muscle endurance time and lifting capacity were significantly correlated to rate of return to work. Traditional care plus a graded activity program were superior to only traditional care, evaluated in terms of mobility, strength and fitness. The graded activity program proved to be a successful method of restoring occupational function and facilitating return to work in subacute low back pain patients. The patients in the graded activity program learned that it is safe to move, while regaining function. PMID:1385658

  16. 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

  17. 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…

  18. 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...

  19. Mobile Marine Museum.

    ERIC Educational Resources Information Center

    Bauer, R. D.; Schaadt, M. S.

    1984-01-01

    Calfiornia State University (Long Beach) purchased a motor home and converted it into a mobile marine science display unit, outfitting it with built-in display racks inside and an awning to provide shelter displays suited to outdoor use. School activities and programs using the mobile museum are described. (JN)

  20. 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,…

  1. 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.

  2. Electrophoretic separation techniques and their hyphenation to mass spectrometry in biological inorganic chemistry.

    PubMed

    Holtkamp, Hannah; Grabmann, Gerlinde; Hartinger, Christian G

    2016-04-01

    Electrophoretic methods have been widely applied in research on the roles of metal complexes in biological systems. In particular, CE, often hyphenated to a sensitive MS detector, has provided valuable information on the modes of action of metal-based pharmaceuticals, and more recently new methods have been added to the electrophoretic toolbox. The range of applications continues to expand as a result of enhanced CE-to-MS interfacing, with sensitivity often at picomolar level, and evolved separation modes allowing for innovative sample analysis. This article is a followup to previous reviews about CE methods in metallodrug research (Electrophoresis, 2003, 24, 2023-2037; Electrophoresis, 2007, 28, 3436-3446; Electrophoresis, 2012, 33, 622-634), also providing a comprehensive overview of metal species studied by electrophoretic methods hyphenated to MS. It highlights the latest CE developments, takes a sneak peek into gel electrophoresis, traces biomolecule labeling, and focuses on the importance of early-stage drug development. PMID:26643265

  3. Nonlinear electrophoretic response yields a unique parameter for separation of biomolecules

    PubMed Central

    Pel, Joel; Broemeling, David; Mai, Laura; Poon, Hau-Ling; Tropini, Giorgia; Warren, René L.; Holt, Robert A.; Marziali, Andre

    2009-01-01

    We demonstrate a unique parameter for biomolecule separation that results from the nonlinear response of long, charged polymers to electrophoretic fields and apply it to extraction and concentration of nucleic acids from samples that perform poorly under conventional methods. Our method is based on superposition of synchronous, time-varying electrophoretic fields, which can generate net drift of charged molecules even when the time-averaged molecule displacement generated by each field individually is zero. Such drift can only occur for molecules, such as DNA, whose motive response to electrophoretic fields is nonlinear. Consequently, we are able to concentrate DNA while rejecting high concentrations of contaminants. We demonstrate one application of this method by extracting DNA from challenging samples originating in the Athabasca oil sands. PMID:19706437

  4. 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. PMID:24594043

  5. Application of high-performance chromatographic and electrophoretic methods to the purification and characterization of glucose oxidase and catalase from Penicillium chrysogenum.

    PubMed

    Eriksson, K O; Kourteva, I; Yao, K Q; Liao, J L; Kilár, F; Hjertén, S; Chaga, G

    1987-06-26

    The high resolving power of the preparative and analytical high-performance chromatographic and electrophoretic methods recently developed in this laboratory for the separation of biopolymers has been demonstrated by the purification and characterization of glucose oxidase and catalase from Penicillium chrysogenum. Crude glucose oxidase was purified to homogeneity in one step by high-performance hydrophobic-interaction chromatography (HIC) on a pentylagarose column. Crude catalase was purified by a combination of HIC and high-performance anion-exchange chromatography on 3-diethylamino-2-hydroxypropylagarose. The homogeneity of the enzymes was monitored by high-performance electrophoresis and free zone electrophoresis. The pI values of these two enzymes determined by isoelectric focusing in the high-performance electrophoresis apparatus were 4.2 and 6.5, respectively. Their molecular weights were determined by high-performance molecular sieve chromatography on an agarose column. Glucose oxidase has a molecular weight of 175,000 and probably consists of two identical subunits, as sodium dodecyl sulphate polyacrylamide gel electrophoresis gave a molecular weight of around 72,000. The molecular weight of catalase, which is probably composed of non-identical subunits, as indicated by sodium dodecyl sulphate electrophoresis, is around 320,000. Some other characteristics of these two enzymes were also investigated, e.g., electrophoretic mobility, pH stability and optimum pH. PMID:3116021

  6. 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.

  7. 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

  8. 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…

  9. 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…

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

    PubMed Central

    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

  11. Separation and Identification of Isomeric Glycans by Selected Accumulation-Trapped Ion Mobility Spectrometry-Electron Activated Dissociation Tandem Mass Spectrometry.

    PubMed

    Pu, Yi; Ridgeway, Mark E; Glaskin, Rebecca S; Park, Melvin A; Costello, Catherine E; Lin, Cheng

    2016-04-01

    One of the major challenges in structural characterization of oligosaccharides is the presence of many structural isomers in most naturally occurring glycan mixtures. Although ion mobility spectrometry (IMS) has shown great promise in glycan isomer separation, conventional IMS separation occurs on the millisecond time scale, largely restricting its implementation to fast time-of-flight (TOF) analyzers which often lack the capability to perform electron activated dissociation (ExD) tandem MS analysis and the resolving power needed to resolve isobaric fragments. The recent development of trapped ion mobility spectrometry (TIMS) provides a promising new tool that offers high mobility resolution and compatibility with high-performance Fourier transform ion cyclotron resonance (FTICR) mass spectrometers when operated under the selected accumulation-TIMS (SA-TIMS) mode. Here, we present our initial results on the application of SA-TIMS-ExD-FTICR MS to the separation and identification of glycan linkage isomers. PMID:26959868

  12. Electrophoretic deposition of hyaluronic acid and composite films for biomedical applications

    NASA Astrophysics Data System (ADS)

    Ma, R.; Li, Y.; Zhitomirsky, I.

    2010-06-01

    Hyaluronic acid (HYH) is a natural biopolymer, which has tremendous potential for various biomedical applications. Electrophoretic deposition (EPD) methods have been developed for the fabrication of HYH films and composites. New methods for the immobilization of drugs and proteins have been utilized for the fabrication of organic composites. Electrophoretic deposition enabled the fabrication of organic-inorganic composites containing bioceramics and bioglass in the HYH matrix. It was shown that the deposition yield, microstructure, and composition of the films can be controlled. Potential applications of EPD for the surface modification of biomedical implants and fabrication of biosensors are highlighted.

  13. Polyacrylamide gel electrophoretic methods in the separation of structural muscle proteins.

    SciTech Connect

    Barany, K.; Barany, M.; Giometti, C. S.; Center for Mechanistic Biology and Biotechnology; Univ. of Illinois at Chicago

    1995-04-28

    Polyacrylamide gel electrophoresis plays a major role in analyzing the function of muscle structural proteins. This review describes one- and two-dimensional gel electrophoretic methods for qualitative and quantitative investigation of the muscle proteins, with special emphasis on determination of protein phosphorylation. The electrophoretic studies established the subunit structures of the muscle proteins, characterized their multiple forms, revealed changes in subunit composition or shifts in isoform distribution of specific proteins during development, upon stimulation or denervation of the muscle. Protein phosphorylation during muscle contraction is preferentially studied by two-dimensional gel electrophoresis. The same method demonstrated protein alterations in human neuromuscular diseases.

  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. Connexin-43 hemichannels mediate cyclic ADP-ribose generation and its Ca2+-mobilizing activity by NAD+/cyclic ADP-ribose transport.

    PubMed

    Song, Eun-Kyung; Rah, So-Young; Lee, Young-Rae; Yoo, Chae-Hwa; Kim, Yu-Ri; Yeom, Ji-Hyun; Park, Kwang-Hyun; Kim, Jong-Suk; Kim, Uh-Hyun; Han, Myung-Kwan

    2011-12-30

    The ADP-ribosyl cyclase CD38 whose catalytic domain resides in outside of the cell surface produces the second messenger cyclic ADP-ribose (cADPR) from NAD(+). cADPR increases intracellular Ca(2+) through the intracellular ryanodine receptor/Ca(2+) release channel (RyR). It has been known that intracellular NAD(+) approaches ecto-CD38 via its export by connexin (Cx43) hemichannels, a component of gap junctions. However, it is unclear how cADPR extracellularly generated by ecto-CD38 approaches intracellular RyR although CD38 itself or nucleoside transporter has been proposed to import cADPR. Moreover, it has been unknown what physiological stimulation can trigger Cx43-mediated export of NAD(+). Here we demonstrate that Cx43 hemichannels, but not CD38, import cADPR to increase intracellular calcium through RyR. We also demonstrate that physiological stimulation such as Fcγ receptor (FcγR) ligation induces calcium mobilization through three sequential steps, Cx43-mediated NAD(+) export, CD38-mediated generation of cADPR and Cx43-mediated cADPR import in J774 cells. Protein kinase A (PKA) activation also induced calcium mobilization in the same way as FcγR stimulation. FcγR stimulation-induced calcium mobilization was blocked by PKA inhibition, indicating that PKA is a linker between FcγR stimulation and NAD(+)/cADPR transport. Cx43 knockdown blocked extracellular cADPR import and extracellular cADPR-induced calcium mobilization in J774 cells. Cx43 overexpression in Cx43-negative cells conferred extracellular cADPR-induced calcium mobilization by the mediation of cADPR import. Our data suggest that Cx43 has a dual function exporting NAD(+) and importing cADPR into the cell to activate intracellular calcium mobilization. PMID:22033928

  16. Electrophoretic Deposition of Carbon Nanotubes over TiO2 Nanotubes: Evaluation of Surface Properties and Biocompatibility

    PubMed Central

    Park, Jung Eun; Park, Il Song; Bae, Tae Sung; Lee, Min Ho

    2014-01-01

    Titanium (Ti) is often used as an orthopedic and dental implant material due to its better mechanical properties, corrosion resistance, and excellent biocompatibility. Formation of TiO2 nanotubes (TiO2 NTs) on titanium is an interesting surface modification to achieve controlled drug delivery and to promote cell growth. Carbon nanotubes (CNTs) possess excellent chemical durability and mechanical strength. The use of CNTs in biomedical applications such as scaffolds has received considerable attention in recent years. The present study aims to modify the surface of titanium by anodizing to form TiO2 NTs and subsequently deposit CNTs over it by electrophoretic deposition (EPD). Characteristic, biocompatibility, and apatite forming ability of the surface modified samples were evaluated. The results of the study reveal that CNTs coating on TiO2 nanotubes help improve the biological activity and this type of surface modification is highly suitable for biomedical applications. PMID:25093017

  17. Electric field-induced lateral mobility of photosystem I in the photosynthetic membrane

    PubMed Central

    Brumfeld, Vlad; Miller, Israel R.; Korenstein, Rafi

    1989-01-01

    Electrophoretic movement of photosystem I (PS I) along the photosynthetic membrane of hypotonically swollen thylakoid vesicles was studied by analyzing the electric field-stimulated delayed luminescence (electrophotoluminescence) emitted from PS I. The electrophoretic mobility was inferred from the differences in electrophotoluminescence (EPL) of the photosynthetic vesicles in presence and absence of trains of low amplitude (<80 V/cm) prepulses of 1 ms duration at 4 ms spacing. The average apparent electric mobility, determined from the time course of EPL increase on one hemisphere or its decrease on the other one, as function of prepulse length and intensity was of the order of 3 · 10-5 cm2V-1s-1. The assymetric distribution of the PS I reached a steady state when the diffusional, electrostatic, and elastic forces balanced the electrophoretic driving force. A lateral diffusion coefficient of ∼5 · 10-9 cm2s-1 was found for the PS I complex from the diffusional relaxation after cessation of the electric field pulse train. Experimental conditions such as concentration, temperature, and viscosity of the aqueous solution were not critical for the effect. Between 23 and 150 electron charges per moving particle were estimated from the measured electrophoretic mobility. PMID:19431746

  18. 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

  19. 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.

  20. 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