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Sample records for functionalized pentacene active

  1. Influence of substitution on the optical properties of functionalized pentacene monomers and crystals: Experiment and theory

    KAUST Repository

    Saeed, Yasir

    2013-10-01

    The influence of solubilizing substitutional groups on the electronic structure of prototypical functionalized pentacene molecules and crystals is studied by a combined experimental and theoretical approach. We experimentally establish characteristic effects of substituents on the electronic structure and relate those to theoretical optical spectra in order to explain the experimental results and provide a comprehensive picture of the substitution effects. Bands associated to C/Si atoms connecting the functional side group to the pentacene in the (6,13)-positions are the main contributors to the optical transitions. The amplitude of the redshift between the crystals and molecules provides insight in the packing structure. © 2013 Elsevier B.V. All rights reserved.

  2. Picosecond Transient Photoconductivity in Functionalized Pentacene Molecular Crystals Probed by Terahertz Pulse Spectroscopy

    Science.gov (United States)

    Hegmann, F. A.; Tykwinski, R. R.; Lui, K. P.; Bullock, J. E.; Anthony, J. E.

    2002-11-01

    We have measured transient photoconductivity in functionalized pentacene molecular crystals using ultrafast optical pump-terahertz probe techniques. The single crystal samples were excited using 800nm, 100fs pulses, and the change in transmission of time-delayed, subpicosecond terahertz pulses was used to probe the photoconducting state over a temperature range from 10 to 300K. A subpicosecond rise in photoconductivity is observed, suggesting that mobile carriers are a primary photoexcitation. At times longer than 4ps, a power-law decay is observed consistent with dispersive transport.

  3. Origins of Singlet Fission in Solid Pentacene from an ab initio Green's Function Approach

    Science.gov (United States)

    Refaely-Abramson, Sivan; da Jornada, Felipe H.; Louie, Steven G.; Neaton, Jeffrey B.

    2017-12-01

    We develop a new first-principles approach to predict and understand rates of singlet fission with an ab initio Green's-function formalism based on many-body perturbation theory. Starting with singlet and triplet excitons computed from a G W plus Bethe-Salpeter equation approach, we calculate the exciton-biexciton coupling to lowest order in the Coulomb interaction, assuming a final state consisting of two noninteracting spin-correlated triplets with finite center-of-mass momentum. For crystalline pentacene, symmetries dictate that the only purely Coulombic fission decay process from a bright singlet state requires a final state consisting of two inequivalent nearly degenerate triplets of nonzero, equal and opposite, center-of-mass momenta. For such a process, we predict a singlet lifetime of 30-70 fs, in very good agreement with experimental data, indicating that this process can dominate singlet fission in crystalline pentacene. Our approach is general and provides a framework for predicting and understanding multiexciton interactions in solids.

  4. Fabrication and characterization of 6,13-bis(triisopropylsilylethynyl)-pentacene active semiconductor thin films prepared by flow-coating method

    Energy Technology Data Exchange (ETDEWEB)

    Mohamad, Khairul Anuar; Rusnan, Fara Naila; Seria, Dzulfahmi Mohd Husin; Saad, Ismail; Alias, Afishah [Nano Engineering & Materials (NEMs) Research Group, Faculty of Engineering Universiti Malaysia Sabah, Kota Kinabalu 88400 Sabah (Malaysia); Katsuhiro, Uesugi; Hisashi, Fukuda [Division of Engineering for Composite Functions, Muroran Institute of Technology 27-1 Mizumoto, Muroran 050-8585 Hokkaido (Japan)

    2015-08-28

    Investigation on the physical characterization and comparison of organic thin film based on a soluble 6,13-bis(triisopropylsilylethynyl) (TIPS) pentacene is reported. Oriented thin-films of pentacene have been successfully deposited by flow-coating method, in which the chloroform solution is sandwiched between a transparent substrate and a slide glass, followed by slow-drawing of the substrate with respect to the slide glass. Molecular orientation of flow-coated TIPS-pentacene is comparable to that of the thermal-evaporated pentacene thin film by the X-ray diffraction (XRD) results. XRD results showed that the morphology of flow-coated soluble pentacene is similar to that of the thermal-evaporated pentacene thin films in series of (00l) diffraction peaks where the (001) diffraction peaks are strongest in the nominally out-of-plane intensity and interplanar spacing located at approximately 2θ = 5.33° (d-spacing, d{sub 001} = 16 Å). Following that, ITO/p-TIPS-pentacene/n-ZnO/Au vertical diode was fabricated. The diode exhibited almost linear characteristics at low voltage with nonlinear characteristics at higher voltage which similar to a pn junction behavior. The results indicated that the TIPS-pentacene semiconductor active thin films can be used as a hole injection layer for fabrication of a vertical organic transistor.

  5. Optimization of pentacene double floating gate memories based on charge injection regulated by SAM functionalization

    Science.gov (United States)

    Li, S.; Guérin, D.; Lenfant, S.; Lmimouni, K.

    2018-02-01

    Pentacene based double nano-floating gate memories (NFGM) by using gold nanoparticles (Au NPs) and reduced graphene oxide (rGO) sheets as charge trapping layers are prepared and demonstrated. Particularly, the NFGM chemically treated by 2,3,4,5,6-pentafluorobenzenethiol (PFBT) self-assembled monolayers (SAM) exhibits excellent memory performances, including high mobility of 0.23 cm2V-1s-1, the large memory window of 51 V, and the stable retention property more than 108 s. Comparing the performances of NFGM without treating with PFBT SAM, the improving performances of the memory devices by SAM modification are explained by the increase of charge injection, which could be further investigated by XPS and UPS. In particular, the results highlight the utility of SAM modulations and controlling of charge transport in the development of organic transistor memories.

  6. Optimization of pentacene double floating gate memories based on charge injection regulated by SAM functionalization

    Directory of Open Access Journals (Sweden)

    S. Li

    2018-02-01

    Full Text Available Pentacene based double nano-floating gate memories (NFGM by using gold nanoparticles (Au NPs and reduced graphene oxide (rGO sheets as charge trapping layers are prepared and demonstrated. Particularly, the NFGM chemically treated by 2,3,4,5,6-pentafluorobenzenethiol (PFBT self-assembled monolayers (SAM exhibits excellent memory performances, including high mobility of 0.23 cm2V-1s-1, the large memory window of 51 V, and the stable retention property more than 108 s. Comparing the performances of NFGM without treating with PFBT SAM, the improving performances of the memory devices by SAM modification are explained by the increase of charge injection, which could be further investigated by XPS and UPS. In particular, the results highlight the utility of SAM modulations and controlling of charge transport in the development of organic transistor memories.

  7. Impact of electron delocalization on the nature of the charge-transfer states in model pentacene/C60 Interfaces: A density functional theory study

    KAUST Repository

    Yang, Bing

    2014-12-04

    Electronic delocalization effects have been proposed to play a key role in photocurrent generation in organic photovoltaic devices. Here, we study the role of charge delocalization on the nature of the charge-transfer (CT) states in the case of model complexes consisting of several pentacene molecules and one fullerene (C60) molecule, which are representative of donor/acceptor heterojunctions. The energies of the CT states are examined by means of time-dependent density functional theory (TD-DFT) using the long-range-corrected functional, ωB97X, with an optimized range-separation parameter, ω. We provide a general description of how the nature of the CT states is impacted by molecular packing (i.e., interfacial donor/acceptor orientations), system size, and intermolecular interactions, features of importance in the understanding of the charge-separation mechanism.

  8. Description of the Charge Transfer States at the Pentacene/C60 Interface: Combining Range-Separated Hybrid Functionals with the Polarizable Continuum Model

    KAUST Repository

    Zheng, Zilong

    2016-06-24

    Density functional theory (DFT) approaches based on range-separated hybrid functionals are currently methods of choice for the description of the charge-transfer (CT) states in organic donor/acceptor solar cells. However, these calculations are usually performed on small-size donor/acceptor complexes and as result do not account for electronic polarization effects. Here, using a pentacene/C60 complex as a model system, we discuss the ability of long-range corrected (LCR) hybrid functionals in combination with the polarizable continuum model (PCM) to determine the impact of the solid-state environment on the CT states. The CT energies are found to be insensitive to the interactions with the dielectric medium when a conventional time-dependent DFT/PCM (TDDFT/PCM) approach is used. However, a decrease in the energy of the CT state in the framework of LRC functionals can be obtained by using a smaller range-separated parameter when going from an isolated donor/acceptor complex to the solid-state case.

  9. Guidelines for bottom-up approach of nanocarbon film formation from pentacene using heated tungsten on quartz substrate without metal catalyst

    Science.gov (United States)

    Heya, Akira; Matsuo, Naoto

    2018-04-01

    The guidelines for a bottom-up approach of nanographene formation from pentacene using heated tungsten were investigated using a novel method called hot mesh deposition (HMD). In this method, a heated W mesh was set between a pentacene source and a quartz substrate. Pentacene molecules were decomposed by the heated W mesh. The generated pentacene-based decomposed precursors were then deposited on the quartz substrate. The pentacene dimer (peripentacene) was obtained from pentacene by HMD using two heated catalysts. As expected from the calculation with the density functional theory in the literature, it was confirmed that the pentacene dimer can be formed by a reaction between pentacene and 6,13-dihydropentacene. This technique can be applied to the formation of novel nanographene on various substrates without metal catalysts.

  10. Azobenzene-functionalized gold nanoparticles as hybrid double-floating-gate in pentacene thin-film transistors/memories with enhanced response, retention, and memory windows.

    Science.gov (United States)

    Tseng, Chiao-Wei; Huang, Ding-Chi; Tao, Yu-Tai

    2013-10-09

    Gold nanoparticles (Au-NPs) with surfaces covered with a self-assembled monolayer of azobenzene derivatives were prepared at the interface of dielectric insulator SiO2 and pentacene thin film. Transistors constructed with these composite channel materials exhibited electric bistability upon different gate biases, with the monolayer serving as a barrier layer, a work function modulator, as well as additional charge trapping sites at the Au-NPs/semiconductor interface at the same time. In comparison with simple alkanethiol monolayer-covered Au-NPs, the CH3-substituted azobenzene-functionalized Au-NPs result in a transistor memory device with about 70% more charges trapped, much faster response time as well as higher retention time. Besides, depending on the substituent on the azobenzene moieties (CH3, H, or CF3) and the tethering alkyl chain length, the speed at which the carriers are trapped (affecting switching response) and the stability of the carriers that are trapped (affecting memory retention) can be modulated to improve the device performance. The structural characterization and electronic characteristics of these devices will be detailed.

  11. Surface-enhanced Raman spectroscopic studies of the Au-pentacene interface: a combined experimental and theoretical investigation.

    Science.gov (United States)

    Adil, D; Guha, S

    2013-07-28

    It has recently been shown [D. Adil and S. Guha, J. Phys. Chem. C 116, 12779 (2012)] that a large enhancement in the Raman intensity due to surface-enhanced Raman scattering (SERS) is observed from pentacene when probed through the Au contact in organic field-effect transistors (OFET) structures. Here, the SERS spectrum is shown to exhibit a high sensitivity to disorder introduced in the pentacene film by Au atoms. The Raman signature of the metal-semiconductor interface in pentacene OFETs is calculated with density-functional theory by explicitly considering the Au-pentacene interaction. The observed enhancement in the 1380 cm(-1) and the 1560 cm(-1) regions of the experimental Raman spectrum of pentacene is successfully modeled by Au-pentacene complexes, giving insights into the nature of disorder in the pentacene sp(2) network. Finally, we extend our previous work on high-operating voltage pentacene OFETs to low-operating voltage pentacene OFETs. No changes in the SERS spectra before and after subjecting the OFETs to a bias stress are observed, concurrent with no degradation in the threshold voltage. This shows that bias stress induced performance degradation is, in part, caused by field-induced structural changes in the pentacene molecule. Thus, we confirm that the SERS spectrum can be used as a visualization tool for correlating transport properties to structural changes, if any, in organic semiconductor based devices.

  12. Surface-enhanced Raman spectroscopic studies of the Au-pentacene interface: A combined experimental and theoretical investigation

    Science.gov (United States)

    Adil, D.; Guha, S.

    2013-07-01

    It has recently been shown [D. Adil and S. Guha, J. Phys. Chem. C 116, 12779 (2012)], 10.1021/jp3031804 that a large enhancement in the Raman intensity due to surface-enhanced Raman scattering (SERS) is observed from pentacene when probed through the Au contact in organic field-effect transistors (OFET) structures. Here, the SERS spectrum is shown to exhibit a high sensitivity to disorder introduced in the pentacene film by Au atoms. The Raman signature of the metal-semiconductor interface in pentacene OFETs is calculated with density-functional theory by explicitly considering the Au-pentacene interaction. The observed enhancement in the 1380 cm-1 and the 1560 cm-1 regions of the experimental Raman spectrum of pentacene is successfully modeled by Au-pentacene complexes, giving insights into the nature of disorder in the pentacene sp2 network. Finally, we extend our previous work on high-operating voltage pentacene OFETs to low-operating voltage pentacene OFETs. No changes in the SERS spectra before and after subjecting the OFETs to a bias stress are observed, concurrent with no degradation in the threshold voltage. This shows that bias stress induced performance degradation is, in part, caused by field-induced structural changes in the pentacene molecule. Thus, we confirm that the SERS spectrum can be used as a visualization tool for correlating transport properties to structural changes, if any, in organic semiconductor based devices.

  13. Surface morphology of vacuum-evaporated pentacene film on Si substrate studied by in situ grazing-incidence small-angle X-ray scattering: I. The initial stage of formation of pentacene film

    Science.gov (United States)

    Hirosawa, Ichiro; Watanabe, Takeshi; Koganezawa, Tomoyuki; Kikuchi, Mamoru; Yoshimoto, Noriyuki

    2018-03-01

    The progress of the surface morphology of a growing sub-monolayered pentacene film on a Si substrate was studied by in situ grazing-incidence small angle X-ray scattering (GISAXS). The observed GISAXS profiles did not show sizes of pentacene islands but mainly protuberances on the boundaries around pentacene film. Scattering of X-ray by residual pits in the pentacene film was also detected in the GISAXS profiles of an almost fully covered film. The average radius of pentacene protuberances increased from 13 to 24 nm as the coverage increased to 0.83 monolayer, and the most frequent radius was almost constant at approximately 9 nm. This result suggests that the population of larger protuberances increase with increasing lengths of boundaries of the pentacene film. It can also be considered that the detected protuberances were crystallites of pentacene, since the average size of protuberances was nearly equal to crystallite sizes of pentacene films. The almost constant characteristic distance of 610 nm and amplitudes of pair correlation functions at low coverages suggest that the growth of pentacene films obeyed the diffusion-limited aggregation (DLA) model, as previously reported. It is also considered that the sites of islands show a triangular distribution for small variations of estimated correlation distances.

  14. Anisotropy of the mobility of pentacene from frustration

    NARCIS (Netherlands)

    de Wijs, GA; Mattheus, CC; de Groot, RA; Palstra, TTM; Wijs, Gilles A. de

    2003-01-01

    The bandstructure of pentacene is calculated using first-principles density functional theory. A large anisotropy of the hole and electron effective masses within the molecular planes is found. The band dispersion of the HOMO and the LUMO is analyzed with the help of a tight-binding (TB) fit. The

  15. Graphene quantum dot (GQD)-induced photovoltaic and photoelectric memory elements in a pentacene/GQD field effect transistor as a probe of functional interface

    Science.gov (United States)

    Kim, Youngjun; Cho, Seongeun; Kim, Hyeran; Seo, Soonjoo; Lee, Hyun Uk; Lee, Jouhahn; Ko, Hyungduk; Chang, Mincheol; Park, Byoungnam

    2017-09-01

    Electric field-induced charge trapping and exciton dissociation were demonstrated at a penatcene/grapheme quantum dot (GQD) interface using a bottom contact bi-layer field effect transistor (FET) as an electrical nano-probe. Large threshold voltage shift in a pentacene/GQD FET in the dark arises from field-induced carrier trapping in the GQD layer or GQD-induced trap states at the pentacene/GQD interface. As the gate electric field increases, hysteresis characterized by the threshold voltage shift depending on the direction of the gate voltage scan becomes stronger due to carrier trapping associated with the presence of a GQD layer. Upon illumination, exciton dissociation and gate electric field-induced charge trapping simultaneously contribute to increase the threshold voltage window, which can potentially be exploited for photoelectric memory and/or photovoltaic devices through interface engineering.

  16. Electrical characteristics of top contact pentacene organic thin film ...

    Indian Academy of Sciences (India)

    such as flat panel displays, large area sensors and low cost RFID tags. Several conjugated polymers and small molecules are widely studied for organic semiconducting active layer in OTFTs. Among organic semiconductors, pentacene has been the leading material for electronic applications with field effect mobilities. 579 ...

  17. Hole mobility in thermally evaporated pentacene: Morphological and directional dependence

    Science.gov (United States)

    Günther, Alrun A.; Widmer, Johannes; Kasemann, Daniel; Leo, Karl

    2015-06-01

    Pentacene has been extensively studied as an active material for organic field-effect transistors as it shows very good charge carrier mobility along its preferred transport direction. In this contribution, we investigate the hole transport in pentacene thin films by measurement in conventional lateral organic field-effect transistors (OFETs), which yields the hole mobility along the a-b plane of pentacene, and by the recently published potential mapping (POEM) approach, which allows for direct extraction of the charge carrier mobility perpendicular to the substrate, in this case perpendicular to the a-b plane, without the assumption of a specific transport model. While the mobility along the a-b plane—determined from OFET measurements—is found to be in the region of 0.45 cm2/Vs, transport perpendicular to this plane shows an average mobility at least one order of magnitude lower. Investigating also how these effective mobility values depend on the deposition rate of the pentacene films, we find that the decrease in grain size for increasing deposition rate causes the mobility to decrease both parallel and perpendicular to the substrate due to the increased number of grain boundaries to be overcome. For the out-of-plane transport, this effect is found to saturate for deposition rates higher than 2.5 Å/s.

  18. Experimental and modeling study of the capacitance-voltage characteristics of metal-insulator-semiconductor capacitor based on pentacene/parylene

    KAUST Repository

    Wondmagegn, Wudyalew T.

    2011-04-01

    The capacitance-voltage (C-V) characteristics of metal-insulator- semiconductor (MIS) capacitors consisting of pentacene as an organic semiconductor and parylene as the dielectric have been investigated by experimental, analytical, and numerical analysis. The device simulation was performed using two-dimensional drift-diffusion methods taking into account the Poole-Frenkel field-dependent mobility. Pentacene bulk defect states and fixed charge density at the semiconductor/insulator interface were incorporated into the simulation. The analysis examined pentacene/parylene interface characteristics for various parylene thicknesses. For each thickness, the corresponding flat band voltage extracted from the C-V plot of the MIS structure was more negative than - 2.4 V. From the flat band voltage the existence of a significant mismatch between the work functions of the gate electrode and pentacene active material has been identified. Experimental and simulation results suggest the existence of interface charge density on the order of 3 × 1011 q/cm2 at the insulator/semiconductor interface. The frequency dispersion characteristics of the device are also presented and discussed. © 2011 Elsevier B.V.

  19. Growth of pentacene on clean and modified gold surfaces

    International Nuclear Information System (INIS)

    Kaefer, Daniel; Ruppel, Lars; Witte, Gregor

    2007-01-01

    The growth and evolution of pentacene films on gold substrates have been studied. By combining complementary techniques including scanning tunneling microscopy, atomic force microscopy, scanning electron microscopy, near-edge x-ray-absorption fine structure, and x-ray diffraction, the molecular orientation, crystalline structure, and morphology of the organic films were characterized as a function of film thickness and growth parameters (temperature and rate) for different gold substrates ranging from Au(111) single crystals to polycrystalline gold. Moreover, the influence of precoating the various gold substrates with self-assembled monolayers (SAM's) of organothiols with different chemical terminations has been studied. On bare gold the growth of pentacene films is characterized by a pronounced dewetting while the molecular orientation within the resulting crystalline three-dimensional islands depends distinctly on the roughness and cleanliness of the substrate surface. After completion of the first wetting layer where molecules adopt a planar orientation parallel to the surface the molecules continue to grow in a tilted fashion: on Au(111) the long molecular axis is oriented parallel to the surface while on polycrystalline gold it is upstanding oriented and thus parallels the crystalline orientation of pentacene films grown on SiO 2 . On SAM pretreated gold substrates the formation of a wetting layer is effectively suppressed and pentacene grows in a quasi-layer-by-layer fashion with an upstanding orientation leading to rather smooth films. The latter growth mode is observed independently of the chemical termination of the SAM's and the roughness of the gold substrate. Possible reasons for the different growth mechanism as well as consequences for the assignment of spectroscopic data of thin pentacene film are discussed

  20. A scanning Kelvin probe study of charge trapping in zone-cast pentacene thin film transistors

    International Nuclear Information System (INIS)

    Hallam, T; Duffy, C M; Ando, M; Sirringhaus, H; Minakata, T

    2009-01-01

    We have used scanning Kelvin probe microscopy (SKPM) as a local probe to study charge trapping in zone-cast pentacene field effect transistors on both SiO 2 and benzocyclobutene (BCB) substrates. Annealing at 130 deg. C was found to reduce the threshold voltage, susceptibility to negative gate bias stress and trapping of positive charges within single pentacene grains. We conclude that oxygen is able to penetrate and disassociatively incorporate into crystalline pentacene, chemically creating electrically active defect states. Screening of a positive gate bias caused by electron injection from Au into pentacene was directly observed with SKPM. The rate of screening was found to change significantly after annealing of the film and depended on the choice of gate dielectric.

  1. Epitaxial growth of pentacene on alkali halide surfaces studied by Kelvin probe force microscopy.

    Science.gov (United States)

    Neff, Julia L; Milde, Peter; León, Carmen Pérez; Kundrat, Matthew D; Eng, Lukas M; Jacob, Christoph R; Hoffmann-Vogel, Regina

    2014-04-22

    In the field of molecular electronics, thin films of molecules adsorbed on insulating surfaces are used as the functional building blocks of electronic devices. Control of the structural and electronic properties of the thin films is required for reliably operating devices. Here, noncontact atomic force and Kelvin probe force microscopies have been used to investigate the growth and electrostatic landscape of pentacene on KBr(001) and KCl(001) surfaces. We have found that, together with molecular islands of upright standing pentacene, a new phase of tilted molecules appears near step edges on KBr. Local contact potential differences (LCPD) have been studied with both Kelvin experiments and density functional theory calculations. Our images reveal that differently oriented molecules display different LCPD and that their value is independent of the number of molecular layers. These results point to the formation of an interface dipole, which may be explained by a partial charge transfer from the pentacene to the surface. Moreover, the monitoring of the evolution of the pentacene islands shows that they are strongly affected by dewetting: Multilayers build up at the expense of monolayers, and in the Kelvin images, previously unknown line defects appear, which reveal the epitaxial growth of pentacene crystals.

  2. Solution processed pentacene thin films and their structural properties

    International Nuclear Information System (INIS)

    Tao Chunlan; Zhang Xuhui; Zhang Fujia; Liu Yiyang; Zhang Haoli

    2007-01-01

    The paper reported the solution process of pentacene thin films from organic solvent O-dichlorobenzene. The pentacene thin films obtained from different conditions were characterized by X-ray diffraction (XRD), optical microscopy, scanning electron microscopy (SEM), and UV-vis spectroscopy. The result shows that the pentacene solution was successfully obtained at a minimum temperature of 40 deg. C. The optimum temperature of forming pentacene thin films was 100 deg. C

  3. A comparison of two crystals of 6, 13-bis (tri-isopropylsilylethynyl) pentacene (TIPS-pentacene) prepared for organic field effect transistors (OFETs)

    Science.gov (United States)

    Murtaza, Ghulam; Ahmad, Ishtiaq; Wu, Jiake

    2015-07-01

    We report on the comparative study of two single crystals grown for organic field effect transistors having different concentration, contact step height, surface roughness and crystallinity of single crystals prepared by droplet pinned crystallization (DPC) method. Organic Field-Effect Transistors (OFETs) consisting of 6, 13-bis (tri-isopropylsilyl-ethynyl) pentacene (TIPS-pentacene) as active semiconducting layer are fabricated. The concentration range of TIPS-pentacene is taken from 0.2 mg/ml to 1.0 mg/ml but for the detailed study, OFETs with concentration of 0.2 mg/ml and 0.6 mg/ml are selected. Five devices for each concentration are fabricated by varying contact positions whereas the top drain and source contacts are made of gold. The calculated values of the threshold voltage, sub threshold slope, Number of interface traps and the saturation mobility of TIPS-pentacene having concentration 0.2 mg/ml are in the range from -12 V to 13 V, -16 (V/decades) to -30 (V/decades), 1.67 × 1012 cm-2 eV-1 to 3.13 × 1012 cm-2 eV-1 and 0.2 to 1.1 cm2/V s while the values for the concentration 0.6 mg/ml are -22 V to 2.6 V,-17 (V/decade) to -22 (V/decade), 1.77 × 1012 cm-2 eV-1 to 2.29 × 1012 cm-2 eV-1 and 2.0-2.2 cm2/V s. The mobility degradation of TIPS-pentacene is found at different gate voltages.

  4. Patterning pentacene surfaces by local oxidation nanolithography

    International Nuclear Information System (INIS)

    Losilla, N.S.; Martinez, J.; Bystrenova, E.; Greco, P.; Biscarini, F.; Garcia, R.

    2010-01-01

    Sequential and parallel local oxidation nanolithographies have been applied to pattern pentacene samples by creating a variety of nanostructures. The sequential local oxidation process is performed with an atomic force microscope and requires the application of a sequence of voltage pulses of 36 V for 1 ms. The parallel local oxidation process is performed by using a conductive and patterned stamp. Then, a voltage pulse is applied between the stamp and the pentacene surface. Patterns formed by arrays of parallel lines covering 1 mm 2 regions and with a periodicity of less than 1 μm have been generated in a few seconds. We also show that the patterns can be used as templates for the deposition of antibodies.

  5. Patterning pentacene surfaces by local oxidation nanolithography

    Energy Technology Data Exchange (ETDEWEB)

    Losilla, N.S., E-mail: nuria@imm.cnm.csic.es [Instituto de Microelectronica de Madrid: CSIC, Isaac Newton 8, 28760 Tres Cantos, Madrid (Spain); Martinez, J. [Instituto de Microelectronica de Madrid: CSIC, Isaac Newton 8, 28760 Tres Cantos, Madrid (Spain); Bystrenova, E.; Greco, P.; Biscarini, F. [Institute for Nanostructured Materials: CNR (ISMN-CNR), Via Gobetti 101, 40129 Bologna (Italy); Garcia, R., E-mail: rgarcia@imm.cnm.csic.es [Instituto de Microelectronica de Madrid: CSIC, Isaac Newton 8, 28760 Tres Cantos, Madrid (Spain)

    2010-05-15

    Sequential and parallel local oxidation nanolithographies have been applied to pattern pentacene samples by creating a variety of nanostructures. The sequential local oxidation process is performed with an atomic force microscope and requires the application of a sequence of voltage pulses of 36 V for 1 ms. The parallel local oxidation process is performed by using a conductive and patterned stamp. Then, a voltage pulse is applied between the stamp and the pentacene surface. Patterns formed by arrays of parallel lines covering 1 mm{sup 2} regions and with a periodicity of less than 1 {mu}m have been generated in a few seconds. We also show that the patterns can be used as templates for the deposition of antibodies.

  6. Raman Identification of Polymorphs in Pentacene Films

    Directory of Open Access Journals (Sweden)

    Alberto Girlando

    2016-04-01

    Full Text Available We use Raman spectroscopy to characterize thin films of pentacene grown on Si/SiO x by Supersonic Molecular Beam Deposition (SuMBD. We find that films up to a thickness of about 781 Å (∼ 52 monolayers all belong to the so-called thin-film (TF phase. The appearance with strong intensity of some lattice phonons suggests that the films are characterized by good intra-layer order. A comparison of the Raman spectra in the lattice and CH bending spectral regions of the TF polymorph with the corresponding ones of the high-temperature (HT and low-temperature (LT bulk pentacene polymorphs provides a quick and nondestructive method to identify the different phases.

  7. Adsorption and electronic properties of pentacene on thin dielectric decoupling layers

    Directory of Open Access Journals (Sweden)

    Sebastian Koslowski

    2017-07-01

    Full Text Available With the increasing use of thin dielectric decoupling layers to study the electronic properties of organic molecules on metal surfaces, comparative studies are needed in order to generalize findings and formulate practical rules. In this paper we study the adsorption and electronic properties of pentacene deposited onto h-BN/Rh(111 and compare them with those of pentacene deposited onto KCl on various metal surfaces. When deposited onto KCl, the HOMO and LUMO energies of the pentacene molecules scale with the work functions of the combined KCl/metal surface. The magnitude of the variation between the respective KCl/metal systems indicates the degree of interaction of the frontier orbitals with the underlying metal. The results confirm that the so-called IDIS model developed by Willenbockel et al. applies not only to molecular layers on bare metal surfaces, but also to individual molecules on thin electronically decoupling layers. Depositing pentacene onto h-BN/Rh(111 results in significantly different adsorption characteristics, due to the topographic corrugation of the surface as well as the lateral electric fields it presents. These properties are reflected in the divergence from the aforementioned trend for the orbital energies of pentacene deposited onto h-BN/Rh(111, as well as in the different adsorption geometry. Thus, the highly desirable capacity of h-BN to trap molecules comes at the price of enhanced metal–molecule interaction, which decreases the HOMO–LUMO gap of the molecules. In spite of the enhanced interaction, the molecular orbitals are evident in scanning tunnelling spectroscopy (STS and their shapes can be resolved by spectroscopic mapping.

  8. The effect of oxygen exposure on pentacene electronic structure

    NARCIS (Netherlands)

    Vollmer, A; Jurchescu, OD; Arfaoui, [No Value; Salzmann, [No Value; Palstra, TTM; Rudolf, P; Niemax, J; Pflaum, J; Rabe, JP; Koch, N; Arfaoui, I.; Salzmann, I.

    We use ultraviolet photoelectron spectroscopy to investigate the effect of oxygen and air exposure on the electronic structure of pentacene single crystals and thin films. it is found that O-2 and water do not react noticeably with pentacene, whereas singlet oxygen/ozone readily oxidize the organic

  9. Energy level alignment symmetry at Co/pentacene/Co interfaces

    NARCIS (Netherlands)

    Popinciuc, M.; Jonkman, H. T.; van Wees, B. J.

    2006-01-01

    We have employed x-ray and ultraviolet photoemission spectroscopies (XPS and UPS) to study the energy level alignment and electronic structure at the Co/pentacene/Co interfaces. In the case of pentacene deposition on Co we found an interfacial dipole of about 1.05 eV and a hole injection barrier of

  10. Synthesis of regioregular pentacene-containing conjugated polymers

    KAUST Repository

    Okamoto, Toshihiro

    2011-01-01

    We report the synthesis and characterization of a new class of regioregular pentacene-containing conjugated polymers via our synthetic routes reported previously. We found that our regioregular pentacene polymers showed improved ordering than their regiorandom counterpart as well as ambipolar OFET performance. © 2011 The Royal Society of Chemistry.

  11. Bis(triisopropylsilylethynyl)pentacene/Au(111) interface: Coupling, molecular orientation, and thermal stability

    KAUST Repository

    Gnoli, Andrea

    2014-10-02

    The assembly and the orientation of functionalized pentacene at the interface with inorganics strongly influence both the electric contact and the charge transport in organic electronic devices. In this study electronic spectroscopies and theoretical modeling are combined to investigate the properties of the bis(triisopropylsilylethynyl)pentacene (TIPS-Pc)/Au(111) interface as a function of the molecular coverage to compare the molecular state in the gas phase and in the adsorbed phase and to determine the thermal stability of TIPS-Pc in contact with gold. Our results show that in the free molecule only the acene atoms directly bonded to the ligands are affected by the functionalization. Adsorption on Au(111) leads to a weak coupling which causes only modest binding energy shifts in the TIPS-Pc and substrate core level spectra. In the first monolayer the acene plane form an angle of 33 ± 2° with the Au(111) surface at variance with the vertical geometry reported for thicker solution-processed or evaporated films, whereas the presence of configurational disorder was observed in the multilayer. The thermal annealing of the TIPS-Pc/Au(111) interface reveals the ligand desorption at ∼470 K, which leaves the backbone of the decomposed molecule flat-lying on the metal surface as in the case of the unmodified pentacene. The weak interaction with the metal substrate causes the molecular dissociation to occur 60 K below the thermal decomposition taking place in thick drop-cast films.

  12. Transport characteristics in Au/pentacene/Au diodes

    Science.gov (United States)

    Hayashi, Toshiaki; Naka, Akiyoshi; Hiroki, Masanobu; Yokota, Tomoyuki; Someya, Takao; Fujiwara, Akira

    2018-03-01

    We have used scanning and transmission electron microscopes (SEM and TEM) to study the structure of a pentacene thin film grown on a Au layer with and shown that it consists of randomly oriented amorphous pentacene clusters. We have also investigated the transport properties of amorphous pentacene in a metal-semiconductor-metal (MSM) diode structure and shown that the current is logarithmically proportional to the square root of the applied voltage, which indicates that transport occurs as the result of hopping between localized sites randomly distributed in space and energy.

  13. First-principles study of the pentacene/Cu(1 1 1) interface: Adsorption states and vacuum level shifts

    International Nuclear Information System (INIS)

    Toyoda, Kenji; Nakano, Yosuke; Hamada, Ikutaro; Lee, Kyuho; Yanagisawa, Susumu; Morikawa, Yoshitada

    2009-01-01

    We have studied the interaction of pentacene with a Cu(1 1 1) surface using density functional theory (DFT) within a generalized gradient approximation (GGA) and the van der Waals density functional [vdW-DF, M. Dion, H. Rydberg, E. Schroeder, D.C. Langreth, B.I. Lundqvist, Phys. Rev. Lett. 92 (2004) 246401]. The adsorption energy is accurately predicted by vdW-DF, while the equilibrium distances between pentacene and the metal substrate (Z C ) are overestimated by both GGA and vdW-DF. The work function changes depend significantly on Z C . The experimental work function change can be successfully reproduced by GGA if the experimentally reported adsorption geometry is used, whereas the magnitude of the work function change is underestimated if calculated adsorption geometries are applied. We examined the IDIS model [H. Vazquez, R. Qszwaldowski, P. Pou, J. Ortega, R. Perez, F. Flores, A. Kahn, Europhys. Lett. 65 (2004) 802] to compare it with the GGA results. The interface dipoles estimated by the IDIS model fairly agree with the GGA results, provided that the adsorption distance is large. On the other hand, they tend to deviate from the GGA results as the adsorption distance becomes smaller, where back donation from the metal surface to the adsorbate occurs. Our analysis reveals that at experimentally reported metal-organic distance, back donation is significant enough to induce polarization of pentacene molecules perpendicular to the surface, which leads to a reduction of the work function. Thus, at the experimentally reported metal-organic distance, the work function change estimated by a simple IDIS model deviates from that calculated by self-consistent GGA calculations. We also found that at the experimentally reported metal-organic distance, the transferred electrons create weak chemical bonds between pentacene and the Cu(1 1 1) surface, illustrating the reactive nature of pentacene.

  14. Effects of the F4TCNQ-Doped Pentacene Interlayers on Performance Improvement of Top-Contact Pentacene-Based Organic Thin-Film Transistors

    Directory of Open Access Journals (Sweden)

    Ching-Lin Fan

    2016-01-01

    Full Text Available In this paper, the top-contact (TC pentacene-based organic thin-film transistor (OTFT with a tetrafluorotetracyanoquinodimethane (F4TCNQ-doped pentacene interlayer between the source/drain electrodes and the pentacene channel layer were fabricated using the co-evaporation method. Compared with a pentacene-based OTFT without an interlayer, OTFTs with an F4TCNQ:pentacene ratio of 1:1 showed considerably improved electrical characteristics. In addition, the dependence of the OTFT performance on the thickness of the F4TCNQ-doped pentacene interlayer is weaker than that on a Teflon interlayer. Therefore, a molecular doping-type F4TCNQ-doped pentacene interlayer is a suitable carrier injection layer that can improve the TC-OTFT performance and facilitate obtaining a stable process window.

  15. Electric bistability induced by incorporating self-assembled monolayers/aggregated clusters of azobenzene derivatives in pentacene-based thin-film transistors.

    Science.gov (United States)

    Tseng, Chiao-Wei; Huang, Ding-Chi; Tao, Yu-Tai

    2012-10-24

    Composite films of pentacene and a series of azobenzene derivatives are prepared and used as the active channel material in top-contact, bottom-gate field-effect transistors. The transistors exhibit high field-effect mobility as well as large I-V hysteresis as a function of the gate bias history. The azobenzene moieties, incorporated either in the form of self-assembled monolayer or discrete multilayer clusters at the dielectric surface, result in electric bistability of the pentacene-based transistor either by photoexcitation or gate biasing. The direction of threshold voltage shifts, size of hysteresis, response time, and retention characteristics all strongly depend on the substituent on the benzene ring. The results show that introducing a monolayer of azobenzene moieties results in formation of charge carrier traps responsible for slower switching between the bistable states and longer retention time. With clusters of azobenzene moieties as the trap sites, the switching is faster but the retention is shorter. Detailed film structure analyses and correlation with the transistor/memory properties of these devices are provided.

  16. The memory effect of a pentacene field-effect transistor with a polarizable gate dielectric

    Science.gov (United States)

    Unni, K. N. N.; de Bettignies, Remi; Dabos-Seignon, Sylvie; Nunzi, Jean-Michel

    2004-06-01

    The nonvolatile transistor memory element is an interesting topic in organic electronics. In this case a memory cell consists of only one device where the stored information is written as a gate insulator polarization by a gate voltage pulse and read by the channel conductance control with channel voltage pulse without destruction of the stored information. Therefore such transistor could be the base of non-volatile non-destructively readable computer memory of extremely high density. Also devices with polarizable gate dielectrics can function more effectively in certain circuits. The effective threshold voltage Vt can be brought very close to zero, for applications where the available gate voltage is limited. Resonant and adaptive circuits can be tuned insitu by polarizing the gates. Poly(vinylidene fluoride), PVDF and its copolymer with trifluoroethylene P(VDF-TrFE) are among the best known and most widely used ferroelectric polymers. In this manuscript, we report new results of an organic FET, fabricated with pentacene as the active material and P(VDF-TrFE) as the gate insulator. Application of a writing voltage of -50 V for short duration results in significant change in the threshold voltage and remarkable increase in the drain current. The memory effect is retained over a period of 20 hours.

  17. Effect of Pentacene-dielectric Affinity on Pentacene Thin Film Growth Morphology in Organic Field-effect Transistors

    Energy Technology Data Exchange (ETDEWEB)

    S Kim; M Jang; H Yang; C Park

    2011-12-31

    Organic field-effect transistors (OFETs) are fabricated by depositing a thin film of semiconductor on the functionalized surface of a SiO{sub 2} dielectric. The chemical and morphological structures of the interface between the semiconductor and the functionalized dielectric are critical for OFET performance. We have characterized the effect of the affinity between semiconductor and functionalized dielectric on the properties of the semiconductor-dielectric interface. The crystalline microstructure/nanostructure of the pentacene semiconductor layers, grown on a dielectric substrate that had been functionalized with either poly(4-vinyl pyridine) or polystyrene (to control hydrophobicity), and grown under a series of substrate temperatures and deposition rates, were characterized by X-ray diffraction, photoemission spectroscopy, and atomic force microscopy. By comparing the morphological features of the semiconductor thin films with the device characteristics (field-effect mobility, threshold voltage, and hysteresis) of the OFET devices, the effect of affinity-driven properties on charge modulation, charge trapping, and charge carrier transport could be described.

  18. High-Mobility Aligned Pentacene Films Grown by Zone-Casting

    DEFF Research Database (Denmark)

    Duffy, Claudia M.; Andreasen, Jens Wenzel; Breiby, Dag W.

    2008-01-01

    We investigate the growth and field-effect transistor performance of aligned pentacene thin films deposited by zone-casting from a solution of unsubstituted pentacene molecules in a chlorinated solvent. Polarized optical microscopy shows that solution processed pentacene films grow as large cryst...

  19. Structural properties 3,16-bis triisopropylsilylethynyl (pentacene) (TIPS-pentacene) thin films onto organic dielectric layer using slide coating method

    International Nuclear Information System (INIS)

    Rusnan, Fara Naila; Mohamad, Khairul Anuar; Seria, Dzul Fahmi Mohd Husin; Saad, Ismail; Ghosh, Bablu K.; Alias, Afishah

    2015-01-01

    3,16-bis triisopropylsilylethynyl (Pentacene) (TIPS-Pentacene) compactable interface property is important in order to have a good arrangement of molecular structure. Comparison for TIPS-Pentacene deposited between two different surface layers conducted. 0.1wt% TIPS-Pentacene diluted in chloroform were deposited onto poly(methylmeaclyrate) (PMMA) layered transparent substrates using slide coating method. X-ray diffraction (XRD) used to determine crystallinity of thin films. Series of (00l) diffraction peaks obtained with sharp first peaks (001) for TIPS-Pentacene deposited onto PMMA layer at 5.35° and separation of 16.3 Å. Morphology and surface roughness were carried out using scanning electron microscope (SEM) and surface profilemeter LS500, respectively.TIPS-Pentacene deposited onto PMMA layer formed needled-like-shape grains with 10.26 nm surface roughness. These properties were related as thin film formed and its surface roughness plays important role towards good mobility devices

  20. Structural properties 3,16-bis triisopropylsilylethynyl (pentacene) (TIPS-pentacene) thin films onto organic dielectric layer using slide coating method

    Energy Technology Data Exchange (ETDEWEB)

    Rusnan, Fara Naila; Mohamad, Khairul Anuar; Seria, Dzul Fahmi Mohd Husin; Saad, Ismail; Ghosh, Bablu K.; Alias, Afishah [Nano Engineering & Materials (NEMs) Research Group, Faculty of Engineering Universiti Malaysia Sabah, Kota Kinabalu 88400 Sabah (Malaysia)

    2015-08-28

    3,16-bis triisopropylsilylethynyl (Pentacene) (TIPS-Pentacene) compactable interface property is important in order to have a good arrangement of molecular structure. Comparison for TIPS-Pentacene deposited between two different surface layers conducted. 0.1wt% TIPS-Pentacene diluted in chloroform were deposited onto poly(methylmeaclyrate) (PMMA) layered transparent substrates using slide coating method. X-ray diffraction (XRD) used to determine crystallinity of thin films. Series of (00l) diffraction peaks obtained with sharp first peaks (001) for TIPS-Pentacene deposited onto PMMA layer at 5.35° and separation of 16.3 Å. Morphology and surface roughness were carried out using scanning electron microscope (SEM) and surface profilemeter LS500, respectively.TIPS-Pentacene deposited onto PMMA layer formed needled-like-shape grains with 10.26 nm surface roughness. These properties were related as thin film formed and its surface roughness plays important role towards good mobility devices.

  1. Direct observation of contact and channel resistance in pentacene four-terminal thin-film transistor patterned by laser ablation method

    International Nuclear Information System (INIS)

    Yagi, Iwao; Tsukagoshi, Kazuhito; Aoyagi, Yoshinobu

    2004-01-01

    We established a dry-etching patterning process for the channel formation of pentacene thin-film transistor, and fabricated a four-terminal device equipped with a gate electrode. The four-terminal device enabled us to divide two-terminal source-drain resistance into two components of contact resistance and pentacene channel resistance. We obtained direct evidence of a gate-voltagedependent contact resistance change: the gate-induced charge significantly reduced the contact resistance and increased source-drain current. Furthermore, the temperature dependence of the device clearly indicated that the contact resistance was much higher than the channel resistance and was dominated in the two-terminal total resistance of the device below 120 K. An observed activation energy of 80 meV for contact resistance was higher than that of 42 meV for pentacene channel resistance

  2. Characteristics of terahertz wave modulation using wavelength-selective photoexcitation in pentacene/Si and TIPS pentacene/Si bilayers

    Directory of Open Access Journals (Sweden)

    Hyung Keun Yoo

    2016-11-01

    Full Text Available We demonstrate the characteristics of the optical control of terahertz (THz wave transmission in photoexcited bilayers of pentacene/Si and 6,13-bis(triisopropylsilylethynyl pentacene (TIPS pentacene/Si. The modulation efficiency is influenced significantly by the photoexcitation wavelength of the optical beams. Lower optical absorption of organic materials leads to higher modulation efficiency because the photocarriers excited on Si with a higher diffusion rate and mobility are far more instrumental in increasing the modulation than the excitons generated on the organic layers. Securing a sufficient depth for carrier diffusion on organic layers is also important for increasing the THz modulation efficiency. These findings may be useful for designing highly efficient and spectrally controllable THz wave modulators.

  3. Dynamics of Molecular Orientation Observed Using Angle Resolved Photoemission Spectroscopy during Deposition of Pentacene on Graphite.

    Science.gov (United States)

    Park, Sang Han; Kwon, Soonnam

    2016-04-19

    A real-time method to observe both the structural and the electronic configuration of an organic molecule during deposition is reported for the model system of pentacene on graphite. Structural phase transition of the thin films as a function of coverage is monitored by using in situ angle resolved photoemission spectroscopy (ARPES) results to observe the change of the electronic configuration at the same time. A photoemission theory that uses independent atomic center approximations is introduced to identify the molecular orientation from the ARPES technique. This study provides a practical insight into interpreting ARPES data regarding dynamic changes of molecular orientation during initial growth of molecules on a well-defined surface.

  4. Interpretation of the ultrafast photoinduced processes in pentacene thin films

    DEFF Research Database (Denmark)

    Kuhlman, Thomas Scheby; Kongsted, Jacob; Mikkelsen, Kurt V.

    2010-01-01

    Ambiguity remains in the models explaining the photoinduced dynamics in pentacene thin films as observed in pump-probe experiments. One model advocates exciton fission as governing the evolution of the initially excited species, whereas the other advocates the formation of an excimeric species su...

  5. Impact of regioregularity on thin-film transistor and photovoltaic cell performances of pentacene-containing polymers

    KAUST Repository

    Jiang, Ying

    2012-01-01

    Regioregular pentacene-containing polymers were synthesized with alkylated bithiophene (BT) and cyclopentadithiophene (CPDT) as comonomers. Among them, 2,9-conjugated polymers PnBT-2,9 and PnCPDT-2,9 achieved the best performance in transistor and photovoltaic devices respectively. The former achieved the most highly ordered structures in thin films, yielding ambipolar transistor behavior with hole and electron mobilities up to 0.03 and 0.02 cm 2 V -1 s -1 on octadecylsilane-treated substrates. The latter achieved photovoltaic power conversion efficiencies up to 0.33%. The impact of regioregularity and direction of conjugation-extension (2,9 vs. 2,10), on thin-film order and device performance has been demonstrated for the pentacene-containing polymers for the first time, providing insight towards future functional material design. © 2012 The Royal Society of Chemistry.

  6. High-Performance Nonvolatile Organic Field-Effect Transistor Memory Based on Organic Semiconductor Heterostructures of Pentacene/P13/Pentacene as Both Charge Transport and Trapping Layers.

    Science.gov (United States)

    Li, Wen; Guo, Fengning; Ling, Haifeng; Zhang, Peng; Yi, Mingdong; Wang, Laiyuan; Wu, Dequn; Xie, Linghai; Huang, Wei

    2017-08-01

    Nonvolatile organic field-effect transistor (OFET) memory devices based on pentacene/ N , N '-ditridecylperylene-3,4,9,10-tetracarboxylic diimide (P13)/pentacene trilayer organic heterostructures have been proposed. The discontinuous n-type P13 embedded in p-type pentacene layers can not only provide electrons in the semiconductor layer that facilitates electron trapping process; it also works as charge trapping sites, which is attributed to the quantum well-like pentacene/P13/pentacene organic heterostructures. The synergistic effects of charge trapping in the discontinuous P13 and the charge-trapping property of the poly(4-vinylphenol) (PVP) layer remarkably improve the memory performance. In addition, the trilayer organic heterostructures have also been successfully applied to multilevel and flexible nonvolatile memory devices. The results provide a novel design strategy to achieve high-performance nonvolatile OFET memory devices and allow potential applications for different combinations of various organic semiconductor materials in OFET memory.

  7. Poly(3-hexylthiophene): TIPS-pentacene blends aiming transistor applications

    Energy Technology Data Exchange (ETDEWEB)

    Silva Ozório, Maiza da, E-mail: ozoriounesp@gmail.com; Nogueira, Gabriel Leonardo; Morais, Rogério Miranda; Silva Martin, Cibely da; Constantino, Carlos José Leopoldo; Alves, Neri

    2016-06-01

    Poly(3-hexylthiophene):6,13-bis(triisopropylsilylethynyl)-pentacene (P3HT:TP) blends with a ratio of 1:1 (wt/wt) were deposited via spin coating on anodized oxide (Al{sub 2}O{sub 3}). A phase separation of the compounds was observed, resulting in the formation of crystalline aggregates of TP molecules that segregate vertically on the surface. The form of segregation depends on the oxide surface treatment used. Spectroscopy analysis shows a higher molecular order of P3HT in the blend than for neat film and that TP molecules are also distributed in the polymeric matrix. Regarding the OFET characteristics, charge carrier mobilities of 1.2 × 10{sup −3} cm{sup 2} V{sup −1} s{sup −1} and 2.0 × 10{sup −3} cm{sup 2} V{sup −1} s{sup −1} were obtained from devices for untreated and (hexamethyldisilazane) HMDS-treated Al{sub 2}O{sub 3} gate dielectric, respectively. These results confirm that P3HT:TP blends have good potential as an active layer in organic field effect transistors (OFETs). - Highlights: • Phase separation occurs in the P3HT:TP blend. • The P3HT:TP blends form aggregates that segregate vertically to the surface. • The molecular order of the P3HT is higher for the blend than for the neat film. • Treatment of surface with HMDS influence in the formation of the aggregate • The P3HT:TP blends have great viability of using for application in transistors.

  8. The energy level alignment at the CH3NH3PbI3/pentacene interface

    International Nuclear Information System (INIS)

    Ji, Gengwu; Zhao, Bin; Song, Fei; Zheng, Guanhaojie; Zhang, Xiaonan; Shen, Kongchao; Yang, Yingguo; Chen, Shi; Gao, Xingyu

    2017-01-01

    Highlights: • The Energy Level Alignment at the CH 3 NH 3 PbI 3 /Pentacene Interface was resolved experimentally. • The downward band bending and the dipole found at the pentacene side would favorably drive holes away from the interface into pentacene. • A ∼0.7 eV offset between pentacene HOMO and CH 3 NH 3 PbI 3 VBM would be in favor of hole transfer whereas a ∼1.35 eV offset between pentacene LUMO and CH 3 NH 3 PbI 3 CBM should efficiently block the unwanted electron transfer from perovskite to pentacene. • Pentacene could be a viable hole transfer material candidate on perovskite to be explored in perovskite devices. - Abstract: Pentacene thin film on CH 3 NH 3 PbI 3 was studied by in-situ X-ray photoelectron spectroscopy and ultraviolet photoelectron spectroscopy to determine their interfacial energy level alignment. A 0.2 eV downward band bending together with a 0.1 eV interfacial dipole was found at the pentacene side, whereas there was no band bending found at the CH 3 NH 3 PbI 3 side. The offset between CH 3 NH 3 PbI 3 Valance Band Maximum (VBM) and pentacene Highest Occupied Molecular Orbital (HOMO) and that between CH 3 NH 3 PbI 3 Conduction Band Minimum (CBM) and pentacene Lowest Unoccupied Molecular Orbital (LUMO) was determined to be 0.7 and 1.35 eV, respectively. The band alignment at this interface is favor of efficient hole transfer, which suggests pentacene as a viable HTL candidate to be explored in perovskite solar cells.

  9. A novel approach for the characterization of a bilayer of phenyl-c71-butyric-acid-methyl ester and pentacene using ultraviolet photoemission spectroscopy and argon gas cluster ion beam sputtering process

    International Nuclear Information System (INIS)

    Yun, Dong-Jin; Chung, JaeGwan; Jung, Changhoon; Chung, Yeonji; Kim, SeongHeon; Lee, Seunghyup; Kim, Ki-Hong; Han, Hyouksoo; Park, Gyeong-Su; Park, SungHoon

    2013-01-01

    The material arrangement and energy level alignment of an organic bilayer comprising of phenyl-c71-butyric-acid-methyl ester (PCBM-71) and pentacene were studied using ultraviolet photoelectron spectroscopy (UPS) and the argon gas cluster ion beam (GCIB) sputtering process. Although there is a small difference in the full width at half maximum of the carbon C 1s core level peaks and differences in the oxygen O 1s core levels of an X-ray photoemission spectroscopy spectra, these differences are insufficient to clearly distinguish between PCBM-71 and pentacene layers and to classify the interface and bulk regions. On the other hand, the valence band structures in the UPS spectra contain completely distinct configurations for the PCBM-71 and pentacene layers, even when they have similar atomic compositions. According to the valence band structures of the PCBM-71/pentacene/electrodes, the highest unoccupied molecular orbital (HOMO) region of pentacene is at least 0.8 eV closer to the Fermi level than that of PCBM-71 and it does not overlap with any of the chemical states in the valence band structure of PCBM-71. Therefore, by just following the variations in the area of the HOMO region of pentacene, the interface/bulk regions of the PCBM/pentacene layers were distinctly categorized. Besides, the variation of valence band structures as a function of the Ar GCIB sputtering time fully corroborated with the surface morphologies observed in the atomic force microscope images. In summary, we believe that the novel approach, which involves UPS analysis in conjunction with Ar GCIB sputtering, can be one of the best methods to characterize the material distribution and energy level alignments of stacks of organic layers

  10. Remarkable reduction in the threshold voltage of pentacene-based thin film transistors with pentacene/CuPc sandwich configuration

    Directory of Open Access Journals (Sweden)

    Yi Li

    2014-06-01

    Full Text Available This study investigates the remarkable reduction in the threshold voltage (VT of pentacene-based thin film transistors with pentacene/copper phthalocyanine (CuPc sandwich configuration. This reduction is accompanied by increased mobility and lowered sub-threshold slope (S. Sandwich devices coated with a 5 nm layer of CuPc layer are compared with conventional top-contact devices, and results indicate that VT decreased significantly from −20.4 V to −0.2 V, that mobility increased from 0.18 cm2/Vs to 0.51 cm2/Vs, and that S was reduced from 4.1 V/dec to 2.9 V/dec. However, the on/off current ratio remains at 105. This enhanced performance could be attributed to the reduction in charge trap density by the incorporated CuPc layer. Results suggest that this method is simple and effectively generates pentacene-based organic thin film transistors with high mobility and low VT.

  11. Chemisorption of pentacene on Pt(111) with a little molecular distortion

    DEFF Research Database (Denmark)

    Brivio, Gian Paolo; Ugolotti, Aldo; Harivyasi, Shashank S.

    2017-01-01

    We investigated the adsorption of pentacene on the (111) surface of platinum, which is an archetypal system for a junction with a low charge-injection barrier. We probed the structural and electronic configurations of pentacene by scanning tunnelling microscopy (STM), X-ray photoemission spectros...

  12. Fast and inexpensive synthesis of pentacene with high yield using 6,13-pentacenequinone as precursor

    Science.gov (United States)

    Mota, María L.; Rodriguez, Bibiana; Carrillo, Amanda; Ambrosio, Roberto C.; Luque, Priscy A.; Mireles, Marcela; Vivaldo, Israel; Quevedo, Manuel A.

    2018-02-01

    Pentacene is an important semiconductor in the field of organic electronics. In this work is presented an alternative synthesis procedure to obtain pentacene from 6,13-pentacenequinone as a precursor. Synthesis of pentacene was performed in two reactions, Diels-Adler cycloaddition of 6,13-pentacenequinone followed by 6,13-pentacenequinone reduction to pentacene, employing LiAlH4 as reducing agent. The products were characterized by Fourier Transform Infrared Spectroscopy (FTIR), 1H-Nuclear Magnetic Resonance Spectroscopy (1H-NMR), X-Ray Diffraction (XRD), Thermogravimetric Analysis (TGA) and Ultraviolet-Visible Spectroscopy (UV-VIS). In this work, 6,13-pentacenequinone was synthetized with a high yield (55%) using an alternative method. The optimization process resulted in an overall reduction of reaction time while exhibiting high yield. The method presented here provides an affordable pentacene synthesis route with high purity, which can be further applied for research and development of organic electronic applications.

  13. Effects of pentacene-doped PEDOT:PSS as a hole-conducting layer on the performance characteristics of polymer photovoltaic cells

    OpenAIRE

    Kim, Hyunsoo; Lee, Jungrae; Ok, Sunseong; Choe, Youngson

    2012-01-01

    We have investigated the effect of pentacene-doped poly(3,4-ethylenedioxythiophene:poly(4-styrenesulfonate) [PEDOT:PSS] films as a hole-conducting layer on the performance of polymer photovoltaic cells. By increasing the amount of pentacene and the annealing temperature of pentacene-doped PEDOT:PSS layer, the changes of performance characteristics were evaluated. Pentacene-doped PEDOT:PSS thin films were prepared by dissolving pentacene in 1-methyl-2-pyrrolidinone solvent and mixing with PEDO...

  14. Non-linear optics of nano-scale pentacene thin film

    Science.gov (United States)

    Yahia, I. S.; Alfaify, S.; Jilani, Asim; Abdel-wahab, M. Sh.; Al-Ghamdi, Attieh A.; Abutalib, M. M.; Al-Bassam, A.; El-Naggar, A. M.

    2016-07-01

    We have found the new ways to investigate the linear/non-linear optical properties of nanostructure pentacene thin film deposited by thermal evaporation technique. Pentacene is the key material in organic semiconductor technology. The existence of nano-structured thin film was confirmed by atomic force microscopy and X-ray diffraction. The wavelength-dependent transmittance and reflectance were calculated to observe the optical behavior of the pentacene thin film. It has been observed the anomalous dispersion at wavelength λ 800. The non-linear refractive index of the deposited films was investigated. The linear optical susceptibility of pentacene thin film was calculated, and we observed the non-linear optical susceptibility of pentacene thin film at about 6 × 10-13 esu. The advantage of this work is to use of spectroscopic method to calculate the liner and non-liner optical response of pentacene thin films rather than expensive Z-scan. The calculated optical behavior of the pentacene thin films could be used in the organic thin films base advanced optoelectronic devices such as telecommunications devices.

  15. The interplay of topography and energy dissipation in pentacene thin films

    Energy Technology Data Exchange (ETDEWEB)

    Wall, S., E-mail: simone.wall@uni-due.de [Department of Physics and Center for Nanointegration Duisburg-Essen CENIDE, Universitaet Duisburg-Essen, D-47057 Duisburg (Germany); Thien, D.; Meyer zu Heringdorf, F.-J. [Department of Physics and Center for Nanointegration Duisburg-Essen CENIDE, Universitaet Duisburg-Essen, D-47057 Duisburg (Germany)

    2012-10-15

    Highlights: Black-Right-Pointing-Pointer We observe a lifetime contrast in time-resolved photoemission electron microscopy for thin pentacene films on Si(0 0 1) and ({radical}3 Multiplication-Sign {radical}3)-Ag/Si(1 1 1). Black-Right-Pointing-Pointer Depending on the morphology of the sample the observed lifetime varies by a factor of two. Black-Right-Pointing-Pointer This difference can be explained by the electronic coupling of the pentacene layers to the substrate. -- Abstract: Nonlinear photoemission electron microscopy was used to study the morphology-dependent lifetime of electronic excitations in pentacene islands on Si(0 0 1) and ({radical}3 Multiplication-Sign {radical}3)R30 Degree-Sign -Ag/Si(1 1 1). After an optical excitation of electrons by a {lambda} = 400 nm femtosecond laser pulse the characteristic decay times were measured with spatial resolution in a pump-probe setup. For pentacene on Si(0 0 1), the observed lifetimes vary by a factor of two between the wetting layer and the fractal-shaped pentacene islands. The measured lifetime difference is explained by a difference in the electronic coupling of the pentacene islands and the wetting layer to the substrate. For pentacene on ({radical}3 Multiplication-Sign {radical}3)R30 Degree-Sign -Ag/Si(1 1 1), similar lifetimes are found, although the orientation of the pentacene molecules in the compact islands is rotated. Our findings suggest that electronic excitations in higher layers of the pentacene islands do not diffuse to the interface before they decay.

  16. Surface-directed molecular assembly of pentacene on monolayer graphene for high-performance organic transistors.

    Science.gov (United States)

    Lee, Wi Hyoung; Park, Jaesung; Sim, Sung Hyun; Lim, Soojin; Kim, Kwang S; Hong, Byung Hee; Cho, Kilwon

    2011-03-30

    Organic electronic devices that use graphene electrodes have received considerable attention because graphene is regarded as an ideal candidate electrode material. Transfer and lithographic processes during fabrication of patterned graphene electrodes typically leave polymer residues on the graphene surfaces. However, the impact of these residues on the organic semiconductor growth mechanism on graphene surface has not been reported yet. Here, we demonstrate that polymer residues remaining on graphene surfaces induce a stand-up orientation of pentacene, thereby controlling pentacene growth such that the molecular assembly is optimal for charge transport. Thus, pentacene field-effect transistors (FETs) using source/drain monolayer graphene electrodes with polymer residues show a high field-effect mobility of 1.2 cm(2)/V s. In contrast, epitaxial growth of pentacene having molecular assembly of lying-down structure is facilitated by π-π interaction between pentacene and the clean graphene electrode without polymer residues, which adversely affects lateral charge transport at the interface between electrode and channel. Our studies provide that the obtained high field-effect mobility in pentacene FETs using monolayer graphene electrodes arises from the extrinsic effects of polymer residues as well as the intrinsic characteristics of the highly conductive, ultrathin two-dimensional monolayer graphene electrodes.

  17. Effect of vacuum annealing on evaporated pentacene thin films for memory device applications

    International Nuclear Information System (INIS)

    Gayathri, A.G.; Joseph, C.M.

    2016-01-01

    Graphical abstract: Switching of ITO/pentacene/Al thin films for different annealing temperatures. - Highlights: • Memory device performance in pentacene improved considerably with annealing. • ON/OFF ratio of the pentacene device increases due to annealing. • Threshold voltage reduces from 2.55 V to 1.35 V due to annealing. • Structure of pentacene thin films is also dependent on annealing temperature. - Abstract: Thin films of pentacene were deposited thermally onto glass substrates and annealed at 323 K, 373 K, 423 K, 473 K and 523 K in high vacuum. Effect of annealing on the morphological and structural properties of these films was studied. X-ray diffraction patterns confirmed the crystalline nature of the films. Electrical studies for the use as write once read many (WORM) memory devices were done for the vacuum deposited pentacene thin films on indium tin oxide coated glass. Due to annealing, a sharp increase in the ON/OFF ratio of current and a decrease in threshold voltage were observed at around 373 K. This device showed a stable switching with an ON/OFF current ratio as high as 10 9 and a switching threshold voltage of 1.35 V. The performance of the device degraded above 423 K due to the changes in the crystallinity of the film.

  18. Ultrathin polycrystalline 6,13-Bis(triisopropylsilylethynyl)-pentacene films

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Min-Cherl; Zhang, Dongrong; Nikiforov, Gueorgui O.; Lee, Michael V.; Qi, Yabing, E-mail: Yabing.Qi@oist.jp [Energy Materials and Surface Sciences Unit (EMSS), Okinawa Institute of Science and Technology Graduate University (OIST), 1919-1 Tancha, Onna-son, Okinawa 904-0495 (Japan); Joo Shin, Tae; Ahn, Docheon; Lee, Han-Koo; Baik, Jaeyoon; Shin, Hyun-Joon [Pohang Accelerator Laboratory, POSTECH, Pohang 790-784 (Korea, Republic of)

    2015-03-15

    Ultrathin (<6 nm) polycrystalline films of 6,13-bis(triisopropylsilylethynyl) pentacene (TIPS-P) are deposited with a two-step spin-coating process. The influence of spin-coating conditions on morphology of the resulting film was examined by atomic force microscopy. Film thickness and RMS surface roughness were in the range of 4.0–6.1 and 0.6–1.1 nm, respectively, except for small holes. Polycrystalline structure was confirmed by grazing incidence x-ray diffraction measurements. Near-edge x-ray absorption fine structure measurements suggested that the plane through aromatic rings of TIPS-P molecules was perpendicular to the substrate surface.

  19. Hybrid, Gate-Tunable, van der Waals p–n Heterojunctions from Pentacene and MoS 2

    Energy Technology Data Exchange (ETDEWEB)

    Jariwala, Deep [Department of Materials Science and Engineering and ‡Department of; Howell, Sarah L. [Department of Materials Science and Engineering and ‡Department of; Chen, Kan-Sheng [Department of Materials Science and Engineering and ‡Department of; Kang, Junmo [Department of Materials Science and Engineering and ‡Department of; Sangwan, Vinod K. [Department of Materials Science and Engineering and ‡Department of; Filippone, Stephen A. [Department of Materials Science and Engineering and ‡Department of; Turrisi, Riccardo [Department of Materials Science and Engineering and ‡Department of; Marks, Tobin J. [Department of Materials Science and Engineering and ‡Department of; Lauhon, Lincoln J. [Department of Materials Science and Engineering and ‡Department of; Hersam, Mark C. [Department of Materials Science and Engineering and ‡Department of

    2015-12-18

    The recent emergence of a wide variety of two-dimensional (2D) materials has created new opportunities for device concepts and applications. In particular, the availability of semiconducting transition metal dichalcogenides, in addition to semimetallic graphene and insulating boron nitride, has enabled the fabrication of “all 2D” van der Waals heterostructure devices. Furthermore, the concept of van der Waals heterostructures has the potential to be significantly broadened beyond layered solids. For example, molecular and polymeric organic solids, whose surface atoms possess saturated bonds, are also known to interact via van der Waals forces and thus offer an alternative for scalable integration with 2D materials. Here, we demonstrate the integration of an organic small molecule p-type semiconductor, pentacene, with a 2D n-type semiconductor, MoS2. The resulting p–n heterojunction is gate-tunable and shows asymmetric control over the antiambipolar transfer characteristic. In addition, the pentacene/MoS2 heterojunction exhibits a photovoltaic effect attributable to type II band alignment, which suggests that MoS2 can function as an acceptor in hybrid solar cells.

  20. Low-voltage bendable pentacene thin-film transistor with stainless steel substrate and polystyrene-coated hafnium silicate dielectric.

    Science.gov (United States)

    Yun, Dong-Jin; Lee, Seunghyup; Yong, Kijung; Rhee, Shi-Woo

    2012-04-01

    The hafnium silicate and aluminum oxide high-k dielectrics were deposited on stainless steel substrate using atomic layer deposition process and octadecyltrichlorosilane (OTS) and polystyrene (PS) were treated improve crystallinity of pentacene grown on them. Besides, the effects of the pentacene deposition condition on the morphologies, crystallinities and electrical properties of pentacene were characterized. Therefore, the surface treatment condition on dielectric and pentacene deposition conditions were optimized. The pentacene grown on polystyrene coated high-k dielectric at low deposition rate and temperature (0.2-0.3 Å/s and R.T.) showed the largest grain size (0.8-1.0 μm) and highest crystallinity among pentacenes deposited various deposition conditions, and the pentacene TFT with polystyrene coated high-k dielectric showed excellent device-performance. To decrease threshold voltage of pentacene TFT, the polystyrene-thickness on high-k dielectric was controlled using different concentration of polystyrene solution. As the polystyrene-thickness on hafnium silicate decreases, the dielectric constant of polystyrene/hafnium silicate increases, while the crystallinity of pentacene grown on polystyrene/hafnium silicate did not change. Using low-thickness polystyrene coated hafnium silicate dielectric, the high-performance and low voltage operating (1 × 10(4)) and complementary inverter (DC gains, ~20) could be fabricated.

  1. Self-interaction corrections applied to Mg-porphyrin, C60, and pentacene molecules

    International Nuclear Information System (INIS)

    Pederson, Mark R.; Baruah, Tunna; Basurto, Luis; Kao, Der-you

    2016-01-01

    We have applied a recently developed method to incorporate the self-interaction correction through Fermi orbitals to Mg-porphyrin, C 60 , and pentacene molecules. The Fermi-Löwdin orbitals are localized and unitarily invariant to the Kohn-Sham orbitals from which they are constructed. The self-interaction-corrected energy is obtained variationally leading to an optimum set of Fermi-Löwdin orbitals (orthonormalized Fermi orbitals) that gives the minimum energy. A Fermi orbital, by definition, is dependent on a certain point which is referred to as the descriptor position. The degree to which the initial choice of descriptor positions influences the variational approach to the minimum and the complexity of the energy landscape as a function of Fermi-orbital descriptors is examined in detail for Mg-porphyrin. The applications presented here also demonstrate that the method can be applied to larger molecular systems containing a few hundred electrons. The atomization energy of the C 60 molecule within the Fermi-Löwdin-orbital self-interaction-correction approach is significantly improved compared to local density approximation in the Perdew-Wang 92 functional and generalized gradient approximation of Perdew-Burke-Ernzerhof functionals. The eigenvalues of the highest occupied molecular orbitals show qualitative improvement.

  2. Characteristics of carrier-generated field-effect transistors with pentacene/vanadium pentoxide

    Energy Technology Data Exchange (ETDEWEB)

    Minagawa, M. [Nagaoka National College of Technology, Niigata (Japan); Nakai, K.; Baba, A.; Shinbo, K.; Kato, K.; Kaneko, F. [Niigata University, Niigata (Japan); Lee, C. [Inha University, Incheon (Korea, Republic of)

    2011-05-15

    In this paper, the driving mechanism of carrier-generated organic field-effect transistors (OFETs) with pentacene and vanadium pentoxide (V{sub 2}O{sub 5}) layers is discussed. In this study, large on-currents were observed in an OFET with a 35-nm V{sub 2}O{sub 5} layer. Devices with aluminum (Al)/pentacene/V{sub 2}O{sub 5}/Al layer structures were also prepared. These devices exhibited a large current density in spite of their high carrier injection barriers between each layer and the Al electrodes. Moreover, new absorption bands corresponding to the radical cation absorption of pentacene were observed within the absorption spectrum of the pentacene and V{sub 2}O{sub 5} mixed layers. It was inferred that the charge transfer (CT) complexes that formed at the interface between the pentacene and V{sub 2}O{sub 5} layers were dissociated by the applied gate voltage and that the generated holes contributed to driving the OFETs.

  3. Current-Induced Joule Heating and Electrical Field Effects in Low Temperature Measurements on TIPS Pentacene Thin Film Transistors

    NARCIS (Netherlands)

    Nikiforov, G.O.; Venkateshvaran, D.; Mooser, S.; Meneau, A.; Strobel, T.; Kronemeijer, A.; Jiang, L.; Lee, M.J.; Sirringhaus, H.

    2016-01-01

    The channel temperature (Tch) of solution-processed 6,13-bis(triisopropylsilylethynyl)-pentacene (TIPS pentacene) thin film transistors (TFTs) is closely monitored in real time during current–voltage (I–V) measurements carried out in a He exchange gas cryostat at various base temperatures (Tb)

  4. Electronic structure of ClAlPc/pentacene/ITO interfaces studied by using soft X-ray spectroscopy

    International Nuclear Information System (INIS)

    Cho, Sangwan; Lee, Sangho; Kim, Minsoo; Heo, Nari; Lee, Geunjeong; Smith, Kevin E.

    2014-01-01

    The interfacial electronic structure of a bilayer of chloroaluminum phthalocyanine (ClAlPc) and pentacene grown on indium tin oxide (ITO) has been studied using synchrotron-radiation-excited photoelectron spectroscopy. The energy difference between the highest occupied molecular orbital (HOMO) level of the pentacene layer and the lowest unoccupied molecular orbital (LUMO) level of the ClAlPc layer (E D HOMO - E A LUMO ) was determined and compared with that of C 60 / pentacene bilayers. The E D HOMO - E A LUMO of a heterojunction with ClAlPc was found to be 1.3 eV while that with C 60 was 0.9 eV. This difference is discussed in terms of the difference in the ionization energy of each acceptor materials. We also obtained the complete energy level diagrams of both ClAlPc/pentacene/ITO and C 60 /pentacene/ITO.

  5. Effect of passivation on the sensitivity and stability of pentacene transistor sensors in aqueous media

    KAUST Repository

    Khan, Hadayat Ullah

    2011-06-01

    Charge-detecting biosensors have recently become the focal point of biosensor research, especially research onto organic thin-film transistors (OTFTs), which combine compactness, a low cost, and fast and label-free detection to realize simple and stable in vivo diagnostic systems. We fabricated organic pentacene-based bottom-contact thin-film transistors with an ultra-thin insulating layer of a cyclized perfluoro polymer called CYTOP (Asahi Glass Co., Tokyo, Japan) on SiO2 for operation in aqueous media. The stability and sensitivity of these transistor sensors were examined in aqueous buffer media with solutions of variable pH levels after the passivation of perfluoro polymers with thicknesses ranging from 50 to 300nm. These transistor sensors were further modified with an ultra-thin film (5nm) functional layer for selective BSA/antiBSA detection in aqueous buffer media, demonstrating a detection capability as low as 500nM of concentrated antiBSA. The dissociation constant from the antiBSA detection results was 2.1×10-6M. Thus, this study represents a significant step forward in the development of organic electronics for a disposable and versatile chemical and bio-sensing platform. © 2011 Elsevier B.V.

  6. Hysteresis mechanism and control in pentacene organic field-effect transistors with polymer dielectric

    Directory of Open Access Journals (Sweden)

    Wei Huang

    2013-05-01

    Full Text Available Hysteresis mechanism of pentacene organic field-effect transistors (OFETs with polyvinyl alcohol (PVA and/or polymethyl methacrylate (PMMA dielectrics is studied. Through analyzing the electrical characteristics of OFETs with various PVA/PMMA arrangements, it shows that charge, which is trapped in PVA bulk and at the interface of pentacene/PVA, is one of the origins of hysteresis. The results also show that memory window is proportional to both trap amount in PVA and charge density at the gate/PVA or PVA/pentacene interfaces. Hence, the controllable memory window of around 0 ∼ 10 V can be realized by controlling the thickness and combination of triple-layer polymer dielectrics.

  7. Effects of Polymeric Dielectric Morphology on Pentacene Morphology and Organic TFT Characteristics

    Directory of Open Access Journals (Sweden)

    Ye Rongbin

    2016-01-01

    Full Text Available In this paper, we report on the effects of the polymeric dielectric morphology on pentacene morphology and organic thin film transistor (TFT characteristics. The morphology and thickness of cyclo-olefin polymer (COP dielectric could be controlled by selecting a solvent. Higher the solvent’s boiling point is, thinner and smother COP films could be obtained. Using the solvent of trimethylcyclohexane, the spin-coated COP films of ca. 330 nm with the peak-to-valley of 7.35 nm and the roughness of root mean square of 0.58 nm were obtained, and pentacene TFT showed high mobility of 2.0 cm2V-1s-1, which originated from highly ordering of pentacene thin films deposited on the smoother and thinner COP films.

  8. Nanoscale domains in thin-film pentacene seen by mid-infrared near-field spectroscopy

    Science.gov (United States)

    Keilmann, Fritz; Nickel, Bert; Westermeier, Christian; Liewald, Clemens; Amarie, Sergiu; Cernescu, Adrian

    2015-03-01

    The coexistence of structural phases in thin-film pentacene was known from X-ray diffraction, yet the scale of domain sizes remained unknown due to large-scale averaging. Infrared spectroscopy (classical FTIR) can distinguish different structural phases by slightly shifted molecular vibrational resonances but with spatial resolution not better than about 10 micrometer. When FTIR is paired with near-field microscopy performed by back-scattering infrared radiation from an AFM tip (``nano-FTIR'' allowing 20 nm resolution), Bulk-Phase (BP) domains were readily observed to form cost of the surrounding Thin-Film-Phase (TFP) pentacene. Both the domain interfaces and their continuing dimensional evolution may point to hidden problems for solar conversion systems development, possibly also with molecular materials beyond pentacene.

  9. OTFT with pentacene-gate dielectric interface modified by silicon nanoparticles

    International Nuclear Information System (INIS)

    Jakabovic, J.; Kovac, J.; Srnanek, R.; Guldan, S.; Donoval, D.; Weis, M.; Sokolsky, M.; Cirak, J.; Broch, K.; Schreiber, F.

    2011-01-01

    We have for the first time investigated the structural and electrical properties of pentacene OTFT deposited on the semiconductor-gate insulator interface covered with SiNPs monolayer prepared by the LB method and compared these to a reference sample (without SiNPs). The micro-Raman, AFM and XRD measurements confirmed that the pentacene layer deposited on the semiconductor-gate insulator interface covered with a SiNPs monolayer on both hydrophobic and hydrophilic surfaces changes the structure. The Raman measurements show that the average value of α is between 0.8 and 1.0. The different structural quality of pentacene leads to better OTFTs electrical characteristics mainly saturation current of OTFTs with SiNPs increasing (∼ 2.5 x) with storing time (85 days) in comparison to OTFTs without SiNPs, which decrease similarly after 85 days.

  10. Absence of Intramolecular Singlet Fission in Pentacene-Perylenediimide Heterodimers: The Role of Charge Transfer State.

    Science.gov (United States)

    Wang, Long; Wu, Yishi; Chen, Jianwei; Wang, Lanfen; Liu, Yanping; Yu, Zhenyi; Yao, Jiannian; Fu, Hongbing

    2017-11-16

    A new class of donor-acceptor heterodimers based on two singlet fission (SF)-active chromophores, i.e., pentacene (Pc) and perylenediimide (PDI), was developed to investigate the role of charge transfer (CT) state on the excitonic dynamics. The CT state is efficiently generated upon photoexcitation. However, the resulting CT state decays to different energy states depending on the energy levels of the CT state. It undergoes extremely rapid deactivation to the ground state in polar CH 2 Cl 2 , whereas it undergoes transformation to a Pc triplet in nonpolar toluene. The efficient triplet generation in toluene is not due to SF but CT-mediated intersystem crossing. In light of the energy landscape, it is suggested that the deep energy level of the CT state relative to that of the triplet pair state makes the CT state actually serve as a trap state that cannot undergoes an intramolecular singlet fission process. These results provide guidance for the design of SF materials and highlight the requisite for more widely applicable design principles.

  11. Microstructural control over soluble pentacene deposited by capillary pen printing for organic electronics.

    Science.gov (United States)

    Lee, Wi Hyoung; Min, Honggi; Park, Namwoo; Lee, Junghwi; Seo, Eunsuk; Kang, Boseok; Cho, Kilwon; Lee, Hwa Sung

    2013-08-28

    Research into printing techniques has received special attention for the commercialization of cost-efficient organic electronics. Here, we have developed a capillary pen printing technique to realize a large-area pattern array of organic transistors and systematically investigated self-organization behavior of printed soluble organic semiconductor ink. The capillary pen-printed deposits of organic semiconductor, 6,13-bis(triisopropylsilylethynyl) pentacene (TIPS_PEN), was well-optimized in terms of morphological and microstructural properties by using ink with mixed solvents of chlorobenzene (CB) and 1,2-dichlorobenzene (DCB). Especially, a 1:1 solvent ratio results in the best transistor performances. This result is attributed to the unique evaporation characteristics of the TIPS_PEN deposits where fast evaporation of CB induces a morphological evolution at the initial printed position, and the remaining DCB with slow evaporation rate offers a favorable crystal evolution at the pinned position. Finally, a large-area transistor array was facilely fabricated by drawing organic electrodes and active layers with a versatile capillary pen. Our approach provides an efficient printing technique for fabricating large-area arrays of organic electronics and further suggests a methodology to enhance their performances by microstructural control of the printed organic semiconducting deposits.

  12. 3D reconstruction of pentacene structural organization in top-contact OTFTs via resonant soft X-ray reflectivity

    Science.gov (United States)

    Capelli, Raffaella; Nardi, Marco Vittorio; Toccoli, Tullio; Verucchi, Roberto; Dinelli, Franco; Gelsomini, Carolina; Koshmak, Konstantin; Giglia, Angelo; Nannarone, Stefano; Pasquali, Luca

    2018-01-01

    Herein, we describe the use of soft X-ray reflectivity at the carbon K-edge to study the molecular organization (orientation, structure, and morphology) of pentacene active films in a top-contact transistor geometry. This technique is not affected by sample charging, and it can be applied in the case of insulating substrates. In addition, the sampling depth is not limited to the near-surface region, giving access to buried device interfaces (metal/organic and dielectric/organic). Spectral lineshape simulations, based on ab-initio calculations using a realistic 3D layer-by-layer model, allow us to unravel the details of the molecular organization in all the specific and crucial areas of the active film, overcoming the limitations of conventional approaches. The tilt angle of the long molecular axis in the whole film is found to progressively decrease with respect to the substrate normal from 25° to 0° with the increasing film thickness. A full vertical alignment, optimal for in-plane charge hopping, is reached only after the complete formation of the first five monolayers. Remarkably, starting from the first one in contact with the dielectric substrate, all the monolayers in the stack show a change in orientation with the increasing thickness. On the other hand, at the buried interface with a gold top-contact, the molecules assume a flat orientation that only propagates for two or three monolayers into the organic film. Top-contact devices with the highest performances can thus be obtained using films of at least ten monolayers. This explains the observed thickness dependence of charge mobility in pentacene transistors.

  13. Investigation Performance and Mechanisms of Inverted Polymer Solar Cells by Pentacene Doped P3HT : PCBM

    Directory of Open Access Journals (Sweden)

    Hsin-Ying Lee

    2014-01-01

    Full Text Available The inverted polymer solar cells (PSCs with pentacene-doped P3HT : PCBM absorption layers were fabricated. It was demonstrated that the pentacene doping modulated the electron mobility and the hole mobility in the resulting absorption layer. Furthermore, by varying the doping content, the optimal carrier mobility balance could be obtained. In addition, the pentacene doping led to an improvement in the crystallinity of the resulting films and made an enhancement in the light absorption, which was partly responsible for the performance improvement of the solar cells. Using the space-charge-limited current (SCLC method, it was determined that the balanced carrier mobility (μh/μe=1.000 was nearly achieved when a pentacene doping ratio of 0.065 by weight was doped into the P3HT : PCBM : pentacene absorption layer. Compared with the inverted PSCs without the pentacene doping, the short circuit current density and the power conversion efficiency of the inverted PSCs with the pentacene doping ratio of 0.065 were increased from 9.73 mA/cm2 to 11.26 mA/cm2 and from 3.39% to 4.31%, respectively.

  14. Vibronic relaxation in molecular mixed crystals : Pentacene in naphthalene and p-terphenyl

    NARCIS (Netherlands)

    Hesselink, Wim H.; Wiersma, Douwe A.

    1981-01-01

    Picosecond photon echo techniques are used to measure directly vibronic relaxation times in the first excited singlet state of pentacene in naphthalene and p-terphenyl. In regions of low (< 300 cm–1) and high (> 1000 cm–1) vibrational energy, relaxation is fast (τ <2 ps) due to direct phonon

  15. Observation of Frenkel and charge transfer excitons in pentacene single crystals using spectroscopic generalized ellipsometry

    NARCIS (Netherlands)

    Qi, Dongchen; Su, Haibin; Bastjan, M.; Jurchescu, O. D.; Palstra, T. M.; Wee, Andrew T. S.; Ruebhausen, M.; Rusydi, A.; Rübhausen, M.

    2013-01-01

    We report on the emerging and admixture of Frenkel and charge transfer (CT) excitons near the absorption onset in pentacene single crystals. Using high energy-resolution spectroscopic generalized ellipsometry with in-plane polarization dependence, the excitonic nature of three lowest lying

  16. Key role of molecular kinetic energy in early stages of pentacene island growth

    NARCIS (Netherlands)

    Wu, Yu; Toccoli, Tullio; Zhang, Jian; Koch, Norbert; Iacob, Erica; Pallaoro, Alessia; Iannotta, Salvatore; Rudolf, Petra

    Organic molecular beam deposition is studied systematically at thermal and hyperthermal regimes aiming at investigating the role of molecular kinetic energy on the growth mechanism of pentacene submonolayers on SiO (x) /Si. We show that the kinetic energy of the impinging molecule (E (k) ) plays a

  17. The energy level alignment at the CH{sub 3}NH{sub 3}PbI{sub 3}/pentacene interface

    Energy Technology Data Exchange (ETDEWEB)

    Ji, Gengwu [Shanghai Synchrotron Radiation Facility, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201204 (China); University of Chinese Academy of Science, Beijing 100049 (China); Zhao, Bin; Song, Fei [Shanghai Synchrotron Radiation Facility, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201204 (China); Zheng, Guanhaojie; Zhang, Xiaonan [Shanghai Synchrotron Radiation Facility, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201204 (China); University of Chinese Academy of Science, Beijing 100049 (China); Shen, Kongchao [Department of Physics, Zhejiang University, Hangzhou 310027 (China); Yang, Yingguo [Shanghai Synchrotron Radiation Facility, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201204 (China); Chen, Shi, E-mail: ChenShi@ntu.edu.sg [Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore 637371 (Singapore); Gao, Xingyu, E-mail: gaoxingyu@sinap.ac.cn [Shanghai Synchrotron Radiation Facility, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201204 (China)

    2017-01-30

    Highlights: • The Energy Level Alignment at the CH{sub 3}NH{sub 3}PbI{sub 3}/Pentacene Interface was resolved experimentally. • The downward band bending and the dipole found at the pentacene side would favorably drive holes away from the interface into pentacene. • A ∼0.7 eV offset between pentacene HOMO and CH{sub 3}NH{sub 3}PbI{sub 3} VBM would be in favor of hole transfer whereas a ∼1.35 eV offset between pentacene LUMO and CH{sub 3}NH{sub 3}PbI{sub 3} CBM should efficiently block the unwanted electron transfer from perovskite to pentacene. • Pentacene could be a viable hole transfer material candidate on perovskite to be explored in perovskite devices. - Abstract: Pentacene thin film on CH{sub 3}NH{sub 3}PbI{sub 3} was studied by in-situ X-ray photoelectron spectroscopy and ultraviolet photoelectron spectroscopy to determine their interfacial energy level alignment. A 0.2 eV downward band bending together with a 0.1 eV interfacial dipole was found at the pentacene side, whereas there was no band bending found at the CH{sub 3}NH{sub 3}PbI{sub 3} side. The offset between CH{sub 3}NH{sub 3}PbI{sub 3} Valance Band Maximum (VBM) and pentacene Highest Occupied Molecular Orbital (HOMO) and that between CH{sub 3}NH{sub 3}PbI{sub 3} Conduction Band Minimum (CBM) and pentacene Lowest Unoccupied Molecular Orbital (LUMO) was determined to be 0.7 and 1.35 eV, respectively. The band alignment at this interface is favor of efficient hole transfer, which suggests pentacene as a viable HTL candidate to be explored in perovskite solar cells.

  18. Analysis of the thickness-dependent electrical characteristics in pentacene field-effect devices

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Dongwook; Shin, Hyunji; Choi, Jongsun [Hongik University, Seoul (Korea, Republic of); Zhang, Xue; Park, Jiho; Baang, Sungkeun; Park, Jaehoon [Hallym University, Chuncheon (Korea, Republic of)

    2014-07-15

    In this paper, we report on the important relationship among the capacitance-voltage (C - V) characteristics of metal-insulator-semiconductor (MIS) capacitors, the output currents of pentacene based organic field-effect transistors (OFETs), and the semiconductor layer's thickness. The effect of the semiconductor layer's thickness on the effective channel capacitance, when the MIS capacitors are fully accumulated with sufficient negative bias, was observed to be directly correlated with the magnitude of the saturated output current. The variation in accumulation capacitance of MIS capacitors due to changes in layer thickness is shown to indicate the existence of a channel capacitance. This determines the output currents in the saturation region. Furthermore, the accumulation capacitance appears to decrease notably when the thickness of the pentacene layer is reduced below 20 nm.

  19. Surface crystallographic structures of cellulose nanofiber films and overlayers of pentacene

    Science.gov (United States)

    Nakayama, Yasuo; Mori, Toshiaki; Tsuruta, Ryohei; Yamanaka, Soichiro; Yoshida, Koki; Imai, Kento; Koganezawa, Tomoyuki; Hosokai, Takuya

    2018-03-01

    Cellulose nanofibers or nanocellulose is a promising recently developed biomass and biodegradable material used for various applications. In order to utilize this material as a substrate in organic electronic devices, thorough understanding of the crystallographic structures of the surfaces of the nanocellulose composites and of their interfaces with organic semiconductor molecules is essential. In this work, surface crystallographic structures of nanocellulose films (NCFs) and overlayers of pentacene were investigated by two-dimensional grazing-incidence X-ray diffraction. The NCFs are found to crystallize on solid surfaces with the crystal lattice preserving the same structure of the known bulk phase, whereas distortion of interchain packing toward the surface normal direction is suggested. The pentacene overlayers on the NCFs are found to form the thin-film phase with an in-plane mean crystallite size of over 10 nm.

  20. Quasi-unipolar pentacene films embedded with fullerene for non-volatile organic transistor memories

    International Nuclear Information System (INIS)

    Lee, Juhee; Lee, Sungpyo; Lee, Moo Hyung; Kang, Moon Sung

    2015-01-01

    Quasi-unipolar non-volatile organic transistor memory (NOTM) can combine the best characteristics of conventional unipolar and ambipolar NOTMs and, as a result, exhibit improved device performance. Unipolar NOTMs typically exhibit a large signal ratio between the programmed and erased current signals but also require a large voltage to program and erase the memory cells. Meanwhile, an ambipolar NOTM can be programmed and erased at lower voltages, but the resulting signal ratio is small. By embedding a discontinuous n-type fullerene layer within a p-type pentacene film, quasi-unipolar NOTMs are fabricated, of which the signal storage utilizes both electrons and holes while the electrical signal relies on only hole conduction. These devices exhibit superior memory performance relative to both pristine unipolar pentacene devices and ambipolar fullerene/pentacene bilayer devices. The quasi-unipolar NOTM exhibited a larger signal ratio between the programmed and erased states while also reducing the voltage required to program and erase a memory cell. This simple approach should be readily applicable for various combinations of advanced organic semiconductors that have been recently developed and thereby should make a significant impact on organic memory research

  1. Pentacene-Based Thin Film Transistor with Inkjet-Printed Nanocomposite High-K Dielectrics

    Directory of Open Access Journals (Sweden)

    Chao-Te Liu

    2012-01-01

    Full Text Available The nanocomposite gate insulating film of a pentacene-based thin film transistor was deposited by inkjet printing. In this study, utilizing the pearl miller to crumble the agglomerations and the dispersant to well stabilize the dispersion of nano-TiO2 particles in the polymer matrix of the ink increases the dose concentration for pico-jetting, which could be as the gate dielectric film made by inkjet printing without the photography process. Finally, we realized top contact pentacene-TFTs and successfully accomplished the purpose of directly patternability and increase the performance of the device based on the nanocomposite by inkjet printing. These devices exhibited p-channel TFT characteristics with a high field-effect mobility (a saturation mobility of ̃0.58 cm2 V−1 s−1, a large current ratio (>103 and a low operation voltage (<6 V. Furthermore, we accorded the deposited mechanisms which caused the interface difference between of inkjet printing and spin coating. And we used XRD, SEM, Raman spectroscopy to help us analyze the transfer characteristics of pentacene films and the performance of OTFTs.

  2. Electronic structure of ClAlPc/pentacene/ITO interfaces studied by using soft X-ray spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Sangwan; Lee, Sangho; Kim, Minsoo; Heo, Nari; Lee, Geunjeong [Yonsei University, Wonju (Korea, Republic of); Smith, Kevin E. [Boston University, Boston, MA (United States)

    2014-11-15

    The interfacial electronic structure of a bilayer of chloroaluminum phthalocyanine (ClAlPc) and pentacene grown on indium tin oxide (ITO) has been studied using synchrotron-radiation-excited photoelectron spectroscopy. The energy difference between the highest occupied molecular orbital (HOMO) level of the pentacene layer and the lowest unoccupied molecular orbital (LUMO) level of the ClAlPc layer (E{sup D}{sub HOMO} - E{sup A}{sub LUMO}) was determined and compared with that of C{sub 60}/ pentacene bilayers. The E{sup D}{sub HOMO} - E{sup A}{sub LUMO} of a heterojunction with ClAlPc was found to be 1.3 eV while that with C{sub 60} was 0.9 eV. This difference is discussed in terms of the difference in the ionization energy of each acceptor materials. We also obtained the complete energy level diagrams of both ClAlPc/pentacene/ITO and C{sub 60}/pentacene/ITO.

  3. Electronic Structure of ClAlPc/pentacene/ITO Interfaces Studied by Using Soft X-ray Spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Sang Wan [Yonsei Univ., Wonju (Korea); Lee, Sangho [Yonsei Univ., Wonju (Korea); Kim, Minsoo [Yonsei Univ., Wonju (Korea); Heo, Nari [Yonsei Univ., Wonju (Korea); Lee, Geunjeong [Yonsei Univ., Wonju (Korea); Smith, Kevin E. [Boston Univ., MA (United States)

    2014-12-06

    The interfacial electronic structure of a bilayer of chloroaluminum phthalocyanine (ClAlPc) and pentacene grown on indium tin oxide (ITO) has been studied using synchrotron-radiation-excited photoelectron spectroscopy. The energy difference between the highest occupied molecular orbital (HOMO) level of the pentacene layer and the lowest unoccupied molecular orbital (LUMO) level of the ClAlPc layer (E HOMO D - E LUMO A ) was determined and compared with that of C60/pentacene bilayers. The E HOMO D - E LUMO A of a heterojunction with ClAlPc was found to be 1.3 eV while that with C60 was 0.9 eV. This difference is discussed in terms of the difference in the ionization energy of each acceptor materials. We also obtained the complete energy level diagrams of both ClAlPc/pentacene/ITO and C60/pentacene/ITO.

  4. CFTR activity and mitochondrial function

    Directory of Open Access Journals (Sweden)

    Angel Gabriel Valdivieso

    2013-01-01

    Full Text Available Cystic Fibrosis (CF is a frequent and lethal autosomal recessive disease, caused by mutations in the gene encoding the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR. Before the discovery of the CFTR gene, several hypotheses attempted to explain the etiology of this disease, including the possible role of a chloride channel, diverse alterations in mitochondrial functions, the overexpression of the lysosomal enzyme α-glucosidase and a deficiency in the cytosolic enzyme glucose 6-phosphate dehydrogenase. Because of the diverse mitochondrial changes found, some authors proposed that the affected gene should codify for a mitochondrial protein. Later, the CFTR cloning and the demonstration of its chloride channel activity turned the mitochondrial, lysosomal and cytosolic hypotheses obsolete. However, in recent years, using new approaches, several investigators reported similar or new alterations of mitochondrial functions in Cystic Fibrosis, thus rediscovering a possible role of mitochondria in this disease. Here, we review these CFTR-driven mitochondrial defects, including differential gene expression, alterations in oxidative phosphorylation, calcium homeostasis, oxidative stress, apoptosis and innate immune response, which might explain some characteristics of the complex CF phenotype and reveals potential new targets for therapy.

  5. Activity and functions of VATESI

    International Nuclear Information System (INIS)

    Kutas, S.

    1998-01-01

    Functions of national nuclear safety regulatory authority VATESI are described. The Republic of Lithuania has undertaken a obligation to ensure safety of all nuclear installations under its jurisdiction, including Ignalina NPP, and to establish the legal framework for the nuclear safety regulatory system, namely: national safety rules and requirements, licensing system for nuclear facilities, system for analysis and assessment of nuclear installations. To deal with these issues the Government has established State Nuclear Power Safety Inspectorate (VATESI) on 18 October 1991. In addition to that VATESI performs the following functions to: form the principles and criteria of safety in nuclear energy, safe utilization, transportation and storage of radioactive and nuclear materials, establish safety norms and regulations, issue licenses for the operators of nuclear or radiation related production, prepare and perform inspection programs. VATESI as regulatory body participate in civil emergency preparedness as well. In case of emergency residents of Lithuania will be protected in accordance with the plan for the protection of residents of the Republic of Lithuania in the event of accident of the Ignalina NPP which was adopted by the Prime Minister of the Republic of Lithuania on 4 May 1995. According to the Law on Nuclear Energy Ignalina NPP carries responsibility for nuclear emergency prevention and its consequences elimination. Nuclear emergency and its consequences elimination work is carried out in compliance with Ignalina NPP emergency preparedness plan. This plan is the main operative instruction to carry out organizational, technical, medical, evacuation and other activities to protect the plant personnel and the population

  6. N-Heterocyclic Carbene-Treated Gold Surfaces in Pentacene Organic Field-Effect Transistors: Improved Stability and Contact at the Interface.

    Science.gov (United States)

    Lv, Aifeng; Freitag, Matthias; Chepiga, Kathryn M; Schäfer, Andreas H; Glorius, Frank; Chi, Lifeng

    2018-02-16

    N-Heterocyclic carbene (NHC) molecules, which reacted with the surface of Au electrodes, have been successfully applied in the pentacene transistors. With the application of NHCs, the charge carrier mobility of pentacene transistors increased by five times, while the contact resistance at the pentacene-Au interface reduced down to 85%. Even after annealing the NHC-Au electrodes at 200 oC for two hours before pentacene deposition, the charge carrier mobility of the pentacene transistors did not decrease. The distinguished performance renders the NHCs as excellent alternatives to thiols as metal modifiers for the application in organic field-effect transistors (OFETs). © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Dipolar Quinoidal Acene Analogues as Stable Isoelectronic Structures of Pentacene and Nonacene

    KAUST Repository

    Shi, Xueliang

    2015-10-08

    Quinoidal thia-acene analogues, as the respective isoelectronic structures of pentacene and nonacene, were synthesized and an unusual 1,2-sulfur migration was observed during the Friedel-Crafts alkylation reaction. The analogues display a closed-shell quinoidal structure in the ground state with a distinctive dipolar character. In contrast to their acene isoelectronic structures, both compounds are stable because of the existence of more aromatic sextet rings, a dipolar character, and kinetic blocking. They exhibit unique packing in single crystals resulting from balanced dipole-dipole and [C-H⋯π]/[C-H⋯S] interactions.

  8. A Direct Mechanism of Ultrafast Intramolecular Singlet Fission in Pentacene Dimers

    Science.gov (United States)

    2016-08-24

    Phys. Chem. B 2015, 119, 7644−7650. (17) Zirzlmeier, J.; Lehnherr, D.; Coto, P. B.; Chernick, E. T.; Casillas, R.; Basel , B. S.; Thoss, M.; Tykwinski...Arago,́ J.; Serrano-Perez, J. J.; Ortí, E.; Loṕez Navarrete, J. T.; Takimiya, K.; Casanova, D.; Casado, J.; Goodson, T., III High Yield Ultrafast...theory of singlet exciton fission. III . Crystalline pentacene. J. Chem. Phys. 2014, 141, 074705. (32) Zeng, T.; Hoffmann, R.; Ananth, N. The Low-Lying

  9. An efficient strategy for designing ambipolar organic semiconductor material: Introducing dehydrogenated phosphorus atoms into pentacene core

    Science.gov (United States)

    Tang, Xiao-Dan

    2017-09-01

    The charge transport properties of phosphapentacene (P-PEN) derivatives were systematically explored by theoretical calculation. The dehydrogenated P-PENs have reasonable frontier molecular orbital energy levels to facilitate both electron and hole injection. The reduced reorganization energies of dehydrogenated P-PENs could be intimately connected to the bonding nature of phosphorus atoms. From the idea of homology modeling, the crystal structure of TIPSE-4P-2p is constructed and fully optimized. Fascinatingly, TIPSE-4P-2p shows the intrinsic property of ambipolar transport in both hopping and band models. Thus, introducing dehydrogenated phosphorus atoms into pentacene core could be an efficient strategy for designing ambipolar material.

  10. Asymmetric Response toward Molecular Fluorination in Binary Copper–Phthalocyanine/Pentacene Assemblies

    DEFF Research Database (Denmark)

    de Oteyza, D. G.; García Lastra, Juan Maria; Goiri, E.

    2014-01-01

    We report a didactic and simple example of the subtleness in the balance of intermolecular and molecule–substrate interactions and its effect on molecular self-assembly. The study is performed on two closely related molecular blends of copper phthalocyanines and pentacene, in each of which one of...... intermolecular interactions and a larger corrugation in the molecule–substrate interaction potential, results in a disordered layer. However, the difference between the two blend’s structures vanishes when substrates with less corrugated interaction potentials are used....

  11. Activities To Help in Learning about Functions.

    Science.gov (United States)

    Willoughby, Stephen S.

    1997-01-01

    Describes several activities and games that provide an introduction to the concept of function. Suggests that experiences should depend more on students' experiences and understanding and less on the memorization of unmotivated conventions with abstract symbols. Includes activities for a calculator as a function machine, composite functions, and…

  12. Nonlocal electron-phonon coupling in the pentacene crystal: Beyond the Γ-point approximation

    KAUST Repository

    Yi, Yuanping

    2012-01-01

    There is currently increasing interest in understanding the impact of the nonlocal (Peierls-type) electron-phonon mechanism on charge transport in organic molecular semiconductors. Most estimates of the non-local coupling constants reported in the literature are based on the Γ-point phonon modes. Here, the influence of phonon modes spanning the entire Brillouin zone (phonon dispersion) on the nonlocal electron-phonon couplings is investigated for the pentacene crystal. The phonon modes are obtained by using a supercell approach. The results underline that the overall nonlocal couplings are substantially underestimated by calculations taking sole account of the phonons at the Γ point of the unit cell. The variance of the transfer integrals based on Γ-point normal-mode calculations at room temperature is underestimated in some cases by 40% for herringbone-type dimers and by over 80% for cofacial dimers. Our calculations show that the overall coupling is somewhat larger for holes than for electrons. The results also suggest that the interactions of charge carriers (both electrons and holes) with acoustic and optical phonons are comparable. Therefore, an adequate description of the charge-transport properties in pentacene and similar systems requires that these two electron-phonon coupling mechanisms be treated on the same footing. © 2012 American Institute of Physics.

  13. Angular-dependent EDMR linewidth for spin-dependent space charge limited conduction in a polycrystalline pentacene

    Science.gov (United States)

    Fukuda, Kunito; Asakawa, Naoki

    2017-08-01

    Spin-dependent space charge limited carrier conduction in a Schottky barrier diode using polycrystalline p-type π-conjugated molecular pentacene is explored using multiple-frequency electrically detected magnetic resonance (EDMR) spectroscopy with a variable-angle configuration. The measured EDMR spectra are decomposed into two components derived respectively from mobile and trapped positive polarons. The linewidth of the EDMR signal for the trapped polarons increases with increasing resonance magnetic field for an in-plane configuration where the normal vector of the device substrate is perpendicular to the resonance magnetic field, while it is independent of the field for an out-of-plane configuration. This difference is consistent with the pentacene arrangement on the device substrate, where pentacene molecules exhibit a uniaxial orientation on the out-of-substrate plane. By contrast, the mobile polarons do not show anisotropic behavior with respect to the resonance magnetic field, indicating that the anisotropic effect is averaged out owing to carrier motion. These results suggest that the orientational arrangements of polycrystalline pentacene molecules in a nano thin film play a crucial role in spin-dependent electrical conduction.

  14. Angular-Dependent EDMR Linewidth for Spin-Dependent Space-Charge-Limited Conduction in a Polycrystalline Pentacene

    Directory of Open Access Journals (Sweden)

    Kunito Fukuda

    2017-08-01

    Full Text Available Spin-dependent space-charge-limited carrier conduction in a Schottky barrier diode using polycrystalline p-type π-conjugated molecular pentacene is explored using multiple-frequency electrically detected magnetic resonance (EDMR spectroscopy with a variable-angle configuration. The measured EDMR spectra are decomposed into two components derived, respectively, from mobile and trapped positive polarons. The linewidth of the EDMR signal for the trapped polarons increases with increasing resonance magnetic field for an in-plane configuration where the normal vector of the device substrate is perpendicular to the resonance magnetic field, while it is independent of the field for an out-of-plane configuration. This difference is consistent with the pentacene arrangement on the device substrate, where pentacene molecules exhibit a uniaxial orientation on the out-of-substrate plane. By contrast, the mobile polarons do not show anisotropic behavior with respect to the resonance magnetic field, indicating that the anisotropic effect is averaged out owing to carrier motion. These results suggest that the orientational arrangements of polycrystalline pentacene molecules in a nano thin film play a crucial role in spin-dependent electrical conduction.

  15. Increased mobility and on/off ratio in organic field-effect transistors using low-cost guanine-pentacene multilayers

    Science.gov (United States)

    Shi, Wei; Zheng, Yifan; Taylor, André D.; Yu, Junsheng; Katz, Howard E.

    2017-07-01

    Layer-by-layer deposited guanine and pentacene in organic field-effect transistors (OFETs) is introduced. Through adjusting the layer thickness ratio of guanine and pentacene, the tradeoff of two electronic parameters in OFETs, charge carrier mobility and current on/off ratio, was controlled. The charge mobility was enhanced by depositing pentacene over and between guanine layers and by increasing the proportion of pentacene in the layer-by-layer system, while the current on/off ratio was increased via the decreased off current induced by the guanine layers. The tunable device performance was mainly ascribed to the trap and dopant neutralizing properties of the guanine layers, which would decrease the density of free hydroxyl groups in the OFETs. Furthermore, the cost of the devices could be reduced remarkably via the adoption of low-cost guanine.

  16. Exciton-Dissociation and Charge-Recombination Processes in Pentacene/C 60 Solar Cells: Theoretical Insight into the Impact of Interface Geometry

    KAUST Repository

    Yi, Yuanping

    2009-11-04

    The exciton-dissociation and charge-recombination processes in organic solar cells based on pentacene/C60 heterojunctions are investigated by means of quantum-mechanical calculations. The electronic couplings and the rates of exciton dissociation and charge recombination have been evaluated for several geometrical configurations of the pentacene/C60 complex, which are relevant to bilayer and bulk heterojunctions. The results suggest that, irrespective of the actual pentacene-fullerene orientation, both pentacene-based and C60-based excitons are able to dissociate efficiently. Also, in the case of parallel configurations of the molecules at the pentacene/C60 interface, the decay of the lowest charge-transfer state to the ground state is calculated to be very fast; as a result, it can compete with the dissociation process into mobile charge carriers. Since parallel configurations are expected to be found more frequently in bulk heterojunctions than in bilayer heterojunctions, the performance of pentacene/C60 bulk-heterojunction solar cells is likely to be more affected by charge recombination than that of bilayer devices. © 2009 American Chemical Society.

  17. Singlet-to-triplet intermediates and triplet exciton dynamics in pentacene thinfilms

    Science.gov (United States)

    Thorsmolle, Verner; Korber, Michael; Obergfell, Emanuel; Kuhlman, Thomas; Campbell, Ian; Crone, Brian; Taylor, Antoinette; Averitt, Richard; Demsar, Jure

    Singlet-to-triplet fission in organic semiconductors is a spin-conserving multiexciton process in which one spin-zero singlet excitation is converted into two spin-one triplet excitations on an ultrafast timescale. Current scientific interest into this carrier multiplication process is largely driven by prospects of enhancing the efficiency in photovoltaic applications by generating two long-lived triplet excitons by one photon. The fission process is known to involve intermediate states, known as correlated triplet pairs, with an overall singlet character, before being interchanged into uncorrelated triplets. Here we use broadband femtosecond real-time spectroscopy to study the excited state dynamics in pentacene thin films, elucidating the fission process and the role of intermediate triplet states. VKT and AJT acknowledge support by the LDRD program at Los Alamos National Laboratory and the Department of Energy, Grant No. DE-FG02-04ER118. MK, MO and JD acknowledge support by the Alexander von Humboldt Foundation.

  18. Controlling field-effect mobility in pentacene-based transistors by supersonic molecular-beam deposition

    International Nuclear Information System (INIS)

    Toccoli, T.; Pallaoro, A.; Coppede, N.; Iannotta, S.; De Angelis, F.; Mariucci, L.; Fortunato, G.

    2006-01-01

    We show that pentacene field-effect transistors, fabricated by supersonic molecular beams, have a performance strongly depending on the precursor's kinetic energy (K E ). The major role played by K E is in achieving highly ordered and flat films. In the range K E ≅3.5-6.5 eV, the organic field effect transistor linear mobility increases of a factor ∼5. The highest value (1.0 cm 2 V -1 s -1 ) corresponds to very uniform and flat films (layer-by-layer type growth). The temperature dependence of mobility for films grown at K E >6 eV recalls that of single crystals (bandlike) and shows an opposite trend for films grown at K E ≤5.5 eV

  19. Multiple-trapping in pentacene field-effect transistors with a nanoparticles self-assembled monolayer

    Directory of Open Access Journals (Sweden)

    Keanchuan Lee

    2012-06-01

    Full Text Available A silver nanoparticles self-assembled monolayer (SAM was incorporated in pentacene field-effect transistor and its effects on the carrier injection and transport were investigated using the current-voltage (I − V and impedance spectroscopy (IS measurements. The I − V results showed that there was a significant negative shift of the threshold voltage, indicating the hole trapping inside the devices with about two orders higher in the contact resistance and an order lower in the effective mobility when a SAM was introduced. The IS measurements with the simulation using a Maxwell-Wagner equivalent circuit model revealed the existence of multiple trapping states for the devices with NPs, while the devices without NPs exhibited only a single trap state.

  20. Physical Activity, Aging, and Physiological Function.

    Science.gov (United States)

    Harridge, Stephen D R; Lazarus, Norman R

    2017-03-01

    Human evolution suggests that the default position for health is to be physically active. Inactivity, by contrast, has serious negative effects on health across the lifespan. Therefore, only in physically active people can the inherent aging process proceed unaffected by disuse complications. In such individuals, although the relationship between age and physiological function remains complex, function is generally superior with health, well being, and the aging process optimized. ©2017 Int. Union Physiol. Sci./Am. Physiol. Soc.

  1. Activation of different cerebral functional regions following ...

    African Journals Online (AJOL)

    Background: To explore the brain function regions characteristics of the acupoint combination, this study observed activity changes in the brain regions of healthy volunteers after acupuncture at both Taixi (KI3) and Taichong (LR3) (KI3 + LR3) and KI3 alone using resting-state functional magnetic resonance imaging(fMRI).

  2. Engineering the mobility increment in pentacene-based field-effect transistors by fast cooling of polymeric modification layer

    Science.gov (United States)

    Ling, Haifeng; Zhang, Chenxi; Chen, Yan; Shao, Yaqing; Li, Wen; Li, Huanqun; Chen, Xudong; Yi, Mingdong; Xie, Linghai; Huang, Wei

    2017-06-01

    In this work, we investigate the effect of the cooling rate of polymeric modification layers (PMLs) on the mobility improvement of pentacene-based organic field-effect transistors (OFETs). In contrast to slow cooling (SC), the OFETs fabricated through fast cooling (FC) with PMLs containing side chain-phenyl rings, such as polystyrene (PS) and poly (4-vinylphenol) (PVP), show an obvious mobility incensement compared with that of π-group free polymethylmethacrylate (PMMA). Atomic force microscopy (AFM) images and x-ray diffraction (XRD) characterizations have showed that fast-cooled PMLs could effectively enhance the crystallinity of pentacene, which might be related to the optimized homogeneity of surface energy on the surface of polymeric dielectrics. Our work has demonstrated that FC treatment could be a potential strategy for performance modulation of OFETs.

  3. A pentacene thin film transistor with good performance using sol-gel derived SiO2 gate dielectric layer

    Science.gov (United States)

    Cavas, M.; Al-Ghamdi, Ahmed A.; Al-Hartomy, O. A.; El-Tantawy, F.; Yakuphanoglu, F.

    2013-02-01

    A low-voltage pentacene field-effect transistor with sol-gel derived SiO2 gate dielectric was fabricated. The mobility of the transistor was achieved as high as 1.526 cm2/V on the bared SiO2/Si substrate by a higher dielectric constant. The interface state density for the transistor was found to vary from 3.8 × 1010 to 7.5 × 1010 eV-1 cm-2 at frequency range of 100 kHz-1 MHz. It is evaluated that the SiO2 derived by low cost sol-gel is quite a promising candidate as a gate dielectric layer for low-voltage pentacene field-effect transistor.

  4. Functioning of active postmenopausal women with osteoporosis

    Directory of Open Access Journals (Sweden)

    Aline Cristiane Binda

    Full Text Available Abstract Introduction: The multiple aspects of disability in patients with osteoporosis require comprehensive tool for their assessment. The International Classification of Functioning, Disability and Health (ICF is designed to describe the experience of such patients with theirs functioning. Objective: This study aimed to describe the functioning in a sample of active postmenopausal women with osteoporosis according to the brief ICF core set for osteoporosis. Methods: This cross-sectional study was conducted among active community-dwelling older adults in a southern Brazilian city. Participants were enrolled by convenience sampling from a group conducting supervised aquatic and land-based exercises. Active postmenopausal women with osteoporosis were included. Thirty-two women (mean age 68.0 ± 5.1 years old participated in the evaluation. The brief ICF core set for osteoporosis was used to establish functional profiles. The categories were considered valid when ≥20% of participants showed some disability (according to ICF qualifiers. Results: No category showed a high level of disability, as >50% of women rated by qualifiers .3 or .4. Only the category e580 was considered by all participants as a facilitator. Conclusion: The brief ICF core set for osteoporosis results demonstrated that this classification system is representative to describe the functional profile of the sample. Active postmenopausal women with osteoporosis presented few impairments related to body functions and structures, activities and participation and environmental factors.

  5. Microalbuminuria, Kidney Function, and Daily Physical Activity

    OpenAIRE

    Afsar, Baris

    2013-01-01

    The present study was carried out to investigate independent relationship between daily physical activity, microalbuminuria, and kidney function. The demographic characteristics and laboratory parameters were recorded for all patients. The determination of daily activities was carried out by Nottingham Extended Activities of Daily Living Scale (NEADLS) which was performed for each patient in an interview. Totally 139 patients were enrolled. In the whole group NEADLS score was correlated with ...

  6. Association Between Brain Activation and Functional Connectivity.

    Science.gov (United States)

    Tomasi, Dardo; Volkow, Nora D

    2018-04-13

    The origin of the "resting-state" brain activity recorded with functional magnetic resonance imaging (fMRI) is still uncertain. Here we provide evidence for the neurovascular origins of the amplitude of the low-frequency fluctuations (ALFF) and the local functional connectivity density (lFCD) by comparing them with task-induced blood-oxygen level dependent (BOLD) responses, which are considered a proxy for neuronal activation. Using fMRI data for 2 different tasks (Relational and Social) collected by the Human Connectome Project in 426 healthy adults, we show that ALFF and lFCD have linear associations with the BOLD response. This association was significantly attenuated by a novel task signal regression (TSR) procedure, indicating that task performance enhances lFCD and ALFF in activated regions. We also show that lFCD predicts BOLD activation patterns, as was recently shown for other functional connectivity metrics, which corroborates that resting functional connectivity architecture impacts brain activation responses. Thus, our findings indicate a common source for BOLD responses, ALFF and lFCD, which is consistent with the neurovascular origin of local hemodynamic synchrony presumably reflecting coordinated fluctuations in neuronal activity. This study also supports the development of task-evoked functional connectivity density mapping.

  7. Cerebral blood flow response to functional activation

    DEFF Research Database (Denmark)

    Paulson, Olaf B; Hasselbalch, Steen G; Rostrup, Egill

    2010-01-01

    Cerebral blood flow (CBF) and cerebral metabolic rate are normally coupled, that is an increase in metabolic demand will lead to an increase in flow. However, during functional activation, CBF and glucose metabolism remain coupled as they increase in proportion, whereas oxygen metabolism only...... most distant from the capillaries, whereas other studies point to a shift toward a higher degree of non-oxidative glucose consumption during activation. In this review, we argue that the key mechanism responsible for the regional CBF (rCBF) increase during functional activation is a tight coupling...... between rCBF and glucose metabolism. We assert that uncoupling of rCBF and oxidative metabolism is a consequence of a less pronounced increase in oxygen consumption. On the basis of earlier studies, we take into consideration the functional recruitment of capillaries and attempt to accommodate...

  8. Raman spectroscopy of metal/organic/inorganic heterostructures and pentacene-based OFETs

    Energy Technology Data Exchange (ETDEWEB)

    Paez-Sierra, Beynor Antonio

    2007-12-20

    In the framework of this thesis the interaction of In and Mg as top electrodes on two perylene derivates, 3,4,9,10-perylene tetracarbonic acid dianhydride (PTCDA) and dimethyl-3,4,9,10-perylene tetracarbonic acid diimide (DiMe-PTCDI) was studied. The metal-organic layers wer fabricated on S-passivated GaAs(100)2 x 1 substrates. As main characterization method the Raman spectroscopy was applied. The PTCDA/Mg form themselves by two stages of the metal growth, the first belongs to a new molecular structure for a Mg layer thinner than 2.8 nm, whereby the PTCA molecule loses the oxygen atom from the dianhydride group. The second belongs to the surface-amplified Raman spectrum of the preceding structure. In the case of the Mg/DiMe-PTCDI heterostructures the molecule is well conserved, whereby the Raman shift on the diimide group is not modified. Also this structure shows a coupling between discrete molecule eigenvibrations of 221 cm{sup -1}, 1291 cm{sup -1}, and 1606 cm{sup -1} of the organic material and the electronic continuum states of the Mg metal contact. The studies on the preceding heterostructures helped to analyze experimentally the channel formation of pentacene-based organic field-effect transistors. [German] Im Rahmen dieser Arbeit wurden die Wechselwirkung von In und Mg als Topelektroden auf zwei Perylen-Derivativen, 3,4,9,10-Perylentetracarbonsaure Dianhydrid (PTCDA) und Dimethyl-3,4,9,10- Perylentetracarbonsaure Diimid (DiMe-PTCDI) untersucht. Die Metal/organische Schichten wurden auf S-passivierten GaAs(100):2 x 1-Substraten hergestellt. Als Hauptcharakterisierungsmethode wird die Raman-Spektroskopie eingesetzt. Die PTCDA/Mg Strukturen formen sich durch zwei Stufen des Metallwachstum, die erste gehoert zu einer neuen molekularen Struktur fuer eine Mg Schicht duenner als 2.8 nm, wobei das PTCA-Molekuel das Sauerstoffatom von der Dianhydridgruppe verliert. Die zweite gehoert zu dem oberflaechenverstaerkten Ramanspektrum von der vorherigen Struktur. Im

  9. Adrenocortical function in hospitalised patients with active ...

    African Journals Online (AJOL)

    2006-05-17

    May 17, 2006 ... Tuberculosis (TB) is a major cause of morbidity and mortality in sub-Sah aran Africa, ... To assess whether adrenocortical function was compromised in patients with active tuberculosis. (TB) during the first 5 days of ..... Hernandez-Pando R, de la Luz Streber M, Orozco H, et al. Emergent immunoregulatory.

  10. Opiates and cerebral functional activity in rats

    Energy Technology Data Exchange (ETDEWEB)

    Trusk, T.C.

    1986-01-01

    Cerebral activity was measured using the free-fatty acid (1-/sup 14/C) octanoate as a fast functional tracer in conscious, unrestrained rats 5 minutes after intravenous injection of heroin, cocaine or saline vehicle. Regional changes of octanoate labeling density in the autoradiograms relative to saline-injected animals were used to determine the functional activity effects of each drug. Heroin and cocaine each produced a distinctive pattern of activity increases and suppression throughout the rat brain. Similar regional changes induced by both drugs were found in limbic brain regions implicated in drug reinforcement. Labeled octanoate autoradiography was used to measure the cerebral functional response to a tone that had previously been paired to heroin injections. Rats were trained in groups of three consisting of one heroin self-administration animal, and two animals receiving yoked infusion of heroin or saline. A tone was paired with each infusion during training. Behavioral experiments in similarly trained rats demonstrated that these training conditions impart secondary reinforcing properties to the tone in animals previously self-administering heroin, while the tone remains behaviorally neutral in yoked-infusion rats. Cerebral functional activity was measured during presentation of the tone without drug infusion. Octanoate labeling density changed in fifteen brain areas in response to the tone previously paired to heroin without response contingency. Labeling density was significantly modified in sixteen regions as a result of previously pairing the tone to response-contingent heroin infusions.

  11. Solvent Effect on Morphology and Optical Properties of Poly(3-hexylthiophene):TIPS-Pentacene Blends

    Science.gov (United States)

    Ozório, Maíza Silva; Camacho, Sabrina Alessio; Cordeiro, Neusmar Junior Artico; Duarte, José Leonil; Alves, Neri

    2018-02-01

    Optical, electrical, and morphological properties of poly(3-hexylthiophene):6,13-bis(triisopropylsilylethynyl) (TIPS)-pentacene (P3HT:TP) blend films, in the proportion of 1:1 (w/w), have been investigated using chloroform, toluene, or trichlorobenzene as solvent. The main morphological feature was formation of aggregates that tended to segregate vertically, exhibiting characteristics that were strongly influenced by the type of solvent applied. The phase segregation of TP observed for the P3HT:TP blend film obtained using chloroform, the most volatile of the investigated solvents, can be explained based on the Marangoni effect and the Flory-Huggins model. The TP molecules induce better organization of P3HT, as evidenced by the ultraviolet-visible (UV-Vis) absorption spectra. Photoluminescence (PL) measurements revealed quenching and an increase in the lifetime of the carriers. The PL measurements also showed that the exciton dissociation was dependent on the characteristics of the surface on which the film was deposited. P3HT:TP blend film prepared using trichlorobenzene showed the best morphology with moderate phase segregation and better P3HT ordering. The output current from organic field-effect transistors (OFETs) with blend film prepared using trichlorobenzene was three times (3×) larger than when using the other solvents, with carrier mobility of 5.0 × 10-3 cm2 V-1 s-1.

  12. Structures and magnetism of multinuclear vanadium-pentacene sandwich clusters and their 1D molecular wires.

    Science.gov (United States)

    Zhang, Tingting; Zhu, Liyan; Wu, Qisheng; Yang, Shuo-Wang; Wang, Jinlan

    2012-10-28

    Two types of multinuclear sandwich clusters, (V(3))(n)Pen(n+1), (V(4))(n)Pen(n+1) (Pen = Pentacene; n = 1, 2), and their corresponding infinite one-dimensional (1D) molecular wires ([V(3)Pen](∞), [V(4)Pen](∞)) are investigated theoretically, especially on their magnetic coupling mechanism. These sandwich clusters and molecular wires are found to be of high stability and exhibit intriguing magnetic properties. The intra-layered V atoms in (V(3))(n)Pen(n+1) clusters prefer antiferromagnetic (AFM) coupling, while they can be either ferromagnetic (FM) or AFM coupling in (V(4))(n)Pen(n+1) depending on the intra-layered V-V distances via direct exchange or superexchange mechanism. The inter-layered V atoms favor FM coupling in (V(3))(2)Pen(3), whereas they are AFM coupled in (V(4))(2)Pen(3). Such magnetic behaviors are the consequence of the competition between direct exchange and superexchange interactions among inter-layered V atoms. In contrast, the 1D molecular wires, [V(3)Pen](∞) and [V(4)Pen](∞), appear to be FM metallic with ultra high magnetic moments of 6.8 and 4.0 μ(B) per unit cell respectively, suggesting that they can be served as good candidates for molecular magnets.

  13. Efficient singlet exciton fission in pentacene prepared from a soluble precursor

    Directory of Open Access Journals (Sweden)

    Maxim Tabachnyk

    2016-11-01

    Full Text Available Carrier multiplication using singlet exciton fission (SF to generate a pair of spin-triplet excitons from a single optical excitation has been highlighted as a promising approach to boost the photocurrent in photovoltaics (PVs thereby allowing PV operation beyond the Shockley-Queisser limit. The applicability of many efficient fission materials, however, is limited due to their poor solubility. For instance, while acene-based organics such as pentacene (Pc show high SF yields (up to200%, the plain acene backbone renders the organic molecule insoluble in common organic solvents. Previous approaches adding solubilizing side groups such as bis(tri-iso-propylsilylethynyl to the Pc core resulted in low vertical carrier mobilities due to reduction of the transfer integrals via steric hindrance, which prevented high efficiencies in PVs. Here we show how to achieve good solubility while retaining the advantages of molecular Pc by using a soluble precursor route. The precursor fully converts into molecular Pc through thermal removal of the solubilizing side groups upon annealing above 150 °C in the solid state. The annealed precursor shows small differences in the crystallinity compared to evaporated thin films of Pc, indicating that the Pc adopts the bulk rather than surface polytype. Furthermore, we identify identical SF properties such as sub-100 fs fission time and equally long triplet lifetimes in both samples.

  14. In-situ studies of iodine intercalation in pentacene thin films and single crystals

    Science.gov (United States)

    Haas, S.; Batlogg, B.

    2004-03-01

    One approach to create a finite charge density in organic molecular semiconductors is bulk chemical doping with intercalated charge donors, which is expected, at suitable doping levels, to induce an insulator-to-metal transition. We report on in-situ, time resolved measurements of iodine intercalation in pentacene single crystals and thin films by means of X-ray diffraction and four- and two-terminal electrical resistivity measurements. The iodine vapor pressure was varied between 0.03 and 0.26 torr, while the samples were mostly held at room temperature. Both intercalated single crystals and films show an enhanced interlayer spacing (d_001) of 19.2 Å and 19.4 Årespectively. The resistivity is decreased by several orders of magnitude, thin films showing a near-metallic low temperature behaviour. The iodine is de-intercalated by continuous pumping and sample heating. This results in thin films in a structural change: The 14.4 Å bulk phase has disappeared and only the 15.4 Å thin film phase remains.

  15. Bisindeno-annulated pentacenes with exceptionally high photo-stability and ordered molecular packing: Simple synthesis by a regio-selective Scholl reaction

    KAUST Repository

    Naibi Lakshminarayana, Arun

    2015-01-01

    Bisindeno-annulated pentacenes 3a and 3b were synthesized by a simple regio-selective, FeCl3-mediated Scholl reaction from the corresponding 6,13-diaryl pentacene precursors. The fusion of two indeno-units dramatically changes the electronic properties and chemical reactivity of pentacene and the obtained compounds exhibited exceptionally high photo-stability in the solution, with a half-life time of 11.2 (3a) and 32.0 (3b) days under ambient light and air conditions. Ordered molecular packing with a small π-π stacking distance was observed in the single crystals of 3a and 3b. Our research provides a promising strategy to access stable higher order acenes with controlled molecular order. This journal is

  16. Deep Neural Networks with Multistate Activation Functions

    Directory of Open Access Journals (Sweden)

    Chenghao Cai

    2015-01-01

    Full Text Available We propose multistate activation functions (MSAFs for deep neural networks (DNNs. These MSAFs are new kinds of activation functions which are capable of representing more than two states, including the N-order MSAFs and the symmetrical MSAF. DNNs with these MSAFs can be trained via conventional Stochastic Gradient Descent (SGD as well as mean-normalised SGD. We also discuss how these MSAFs perform when used to resolve classification problems. Experimental results on the TIMIT corpus reveal that, on speech recognition tasks, DNNs with MSAFs perform better than the conventional DNNs, getting a relative improvement of 5.60% on phoneme error rates. Further experiments also reveal that mean-normalised SGD facilitates the training processes of DNNs with MSAFs, especially when being with large training sets. The models can also be directly trained without pretraining when the training set is sufficiently large, which results in a considerable relative improvement of 5.82% on word error rates.

  17. Chemical Composition, antioxidant activity, functional properties and ...

    African Journals Online (AJOL)

    Chemical Composition, antioxidant activity, functional properties and inhibitory action of unripe plantain ( M. Paradisiacae ) flour. ... of dry matter (48.00 ± 3.96%) and starch (31.10 ± 0.44%) but was low in phenol (1.42 ± 0.03%), protein (3.15 ± 0.042%), ash (5.50 ± 0.42%) and total soluble sugar (0.64 ± 0.001%) (p < 0.05).

  18. Synthesis of Dibenzo[h,rst]pentaphenes and Dibenzo[fg,qr]pentacenes by the Chemoselective C-O Arylation of Dimethoxyanthraquinones.

    Science.gov (United States)

    Suzuki, Yusuke; Yamada, Kohei; Watanabe, Kentaro; Kochi, Takuya; Ie, Yutaka; Aso, Yoshio; Kakiuchi, Fumitoshi

    2017-07-21

    A convenient method for the syntheses of dibenzo[h,rst]pentaphenes and dibenzo[fg,qr]pentacenes via the ruthenium-catalyzed chemoselective C-O arylation of 1,4- and 1,5-dimethoxyanthraquinones is described. Dimethoxyanthraquinones reacted selectively with arylboronates at the ortho C-O bonds to give diarylation products. An efficient two-step procedure consisting of a Corey-Chaykofsky reaction and subsequent dehydrative aromatization afforded derivatives of dibenzo[h,rst]pentaphenes and dibenzo[fg,qr]pentacenes. Hole-transporting characteristics were observed for a device with a bottom-contact configuration that was fabricated from one of these polycyclic aromatic hydrocarbons.

  19. Large tunneling anisotropic magnetoresistance in La0.7Sr0.3MnO3/pentacene/Cu structures prepared on SrTiO3 (110) substrates

    Science.gov (United States)

    Kamiya, Takeshi; Miyahara, Chihiro; Tada, Hirokazu

    2017-01-01

    We investigated tunneling anisotropic magnetoresistance (TAMR) at the interface between pentacene and La0.7Sr0.3MnO3 (LSMO) thin films prepared on SrTiO3 (STO) (110) substrates. The dependence of the TAMR ratio on the magnetic field strength was approximately ten times larger than that of the magnetic field angle at a high magnetic field. This large difference in the TAMR ratio is explained by the interface magnetic anisotropy of strain-induced LSMO thin films on a STO (110) substrate, which has an easy axis with an out-of-plane component. We also note that the TAMR owing to out-of-plane magnetization was positive at each angle of the in-plane magnetic field. This result implies that active control of the interface magnetic anisotropy between organic materials and ferromagnetic metals should realize nonvolatile and high-efficiency TAMR devices.

  20. Simulation of the PIR detector active function

    Directory of Open Access Journals (Sweden)

    Drga Rudolf

    2016-01-01

    Full Text Available The work deals with the behaviour of the PIR detector in an environment with great influence of a thermal background. It was necessary to perform simulations of the thermal behaviour of the sensor by COMSOL Multiphysics in different modes of heating the room to be able to prove that the PIR detector can function as an active detector with improved detection possibilities of intruders who would be invisible to a detector under normal circumstances. This confirms the detector’s ability to work on the principle of active detector, i.e. as transmitter and receiver of thermal radiation and evaluation of heat flux changes depending on the type of the heater and the shrouding.

  1. Surface properties of SiO2 with and without H2O2 treatment as gate dielectrics for pentacene thin-film transistor applications

    Science.gov (United States)

    Hung, Cheng-Chun; Lin, Yow-Jon

    2018-01-01

    The effect of H2O2 treatment on the surface properties of SiO2 is studied. H2O2 treatment leads to the formation of Si(sbnd OH)x at the SiO2 surface that serves to reduce the number of trap states, inducing the shift of the Fermi level toward the conduction band minimum. H2O2 treatment also leads to a noticeable reduction in the value of the SiO2 capacitance per unit area. The effect of SiO2 layers with H2O2 treatment on the behavior of carrier transports for the pentacene/SiO2-based organic thin-film transistor (OTFT) is also studied. Experimental identification confirms that the shift of the threshold voltage towards negative gate-source voltages is due to the reduced number of trap states in SiO2 near the pentacene/SiO2 interface. The existence of a hydrogenated layer between pentacene and SiO2 leads to a change in the pentacene-SiO2 interaction, increasing the value of the carrier mobility.

  2. Investigation of pentacene growth on SiO2 gate insulator after photolithography for nitrogen-doped LaB6 bottom-contact electrode formation

    Science.gov (United States)

    Maeda, Yasutaka; Hiroki, Mizuha; Ohmi, Shun-ichiro

    2018-04-01

    Nitrogen-doped (N-doped) LaB6 is a candidate material for the bottom-contact electrode of n-type organic field-effect transistors (OFETs). However, the formation of a N-doped LaB6 electrode affects the surface morphology of a pentacene film. In this study, the effects of surface treatments and a N-doped LaB6 interfacial layer (IL) were investigated to improve the pentacene film quality after N-doped LaB6 electrode patterning with diluted HNO3, followed by resist stripping with acetone and methanol. It was found that the sputtering damage during N-doped LaB6 deposition on a SiO2 gate insulator degraded the crystallinity of pentacene. The H2SO4 and H2O2 (SPM) and diluted HF treatments removed the damaged layer on the SiO2 gate insulator surface. Furthermore, the N-doped LaB6 IL improved the crystallinity of pentacene and realized dendritic grain growth. Owing to these surface treatments, the hole mobility improved from 2.8 × 10‑3 to 0.11 cm2/(V·s), and a steep subthreshold swing of 78 mV/dec for the OFET with top-contact configuration was realized in air even after bottom-contact electrode patterning.

  3. Thermally dried ink-jet process for 6,13-bis(triisopropylsilylethynyl)-pentacene for high mobility and high uniformity on a large area substrate

    Science.gov (United States)

    Ryu, Gi Seong; Lee, Myung Won; Jeong, Seung Hyeon; Song, Chung Kun

    2012-01-01

    In this study we developed a simple ink-jet process for 6,13-bis(triisopropylsilylethynyl)-pentacene (TIPS-pentacene), which is known as a high-mobility soluble organic semiconductor, to achieve relatively high-mobility and high-uniformity performance for large-area applications. We analyzed the behavior of fluorescent particles in droplets and applied the results to determining a method of controlling the behavior of TIPS-pentacene molecules. The grain morphology of TIPS-pentacene varied depending on the temperature applied to the droplets during drying. We were able to obtain large and uniform grains at 46 degrees C without any "coffee stain". The process was applied to a large-size organic thin-film transistor (OTFT) backplane for an electrophoretic display panel containing 192 x 150 pixels on a 6-in.-sized substrate. The average of mobilities of 36 OTFTs, which were taken from different locations of the backplane, was 0.44 +/- 0.08 cm2.V-1.s-1, with a small deviation of 20%, over a 6-in.-size area comprising 28,800 OTFTs. This process providing high mobility and high uniformity can be achieved by simply maintaining the whole area of the substrate at a specific temperature (46 degrees C in this case) during drying of the droplets.

  4. Tensor network methods for the simulation of open quantum dynamics in multichromophore systems: Application to singlet fission in novel pentacene dimers

    Science.gov (United States)

    Chin, Alex

    Singlet fission (SF) is an ultrafast process in which a singlet exciton spontaneously converts into a pair of entangled triplet excitons on neighbouring organic molecules. As a mechanism of multiple exciton generation, it has been suggested as a way to increase the efficiency of organic photovoltaic devices, and its underlying photophysics across a wide range of molecules and materials has attracted significant theoretical attention. Recently, a number of studies using ultrafast nonlinear optics have underscored the importance of intramolecular vibrational dynamics in efficient SF systems, prompting a need for methods capable of simulating open quantum dynamics in the presence of highly structured and strongly coupled environments. Here, a combination of ab initio electronic structure techniques and a new tensor-network methodology for simulating open vibronic dynamics is presented and applied to a recently synthesised dimer of pentacene (DP-Mes). We show that ultrafast (300 fs) SF in this system is driven entirely by symmetry breaking vibrations, and our many-body approach enables the real-time identification and tracking of the ''functional' vibrational dynamics and the role of the ''bath''-like parts of the environment. Deeper analysis of the emerging wave functions points to interesting links between the time at which parts of the environment become relevant to the SF process and the optimal topology of the tensor networks, highlighting the additional insight provided by moving the problem into the natural language of correlated quantum states and how this could lead to simulations of much larger multichromophore systems Supported by The Winton Programme for the Physics of Sustainability.

  5. Cardiovascular function following reduced aerobic activity

    Science.gov (United States)

    Raven, P. B.; Welch-O'Connor, R. M.; Shi, X.; Blomqvist, C. G. (Principal Investigator)

    1998-01-01

    PURPOSE: The aim of this study was to test the hypothesis that a sustained reduction of physical activity (deconditioning) would alter the cardiovascular regulatory function. METHODS: Nineteen young, healthy volunteers participated in physical deconditioning for a period of 8 wk. Before (pre) and following (post) physical deconditioning, the responses of heart rate (HR), mean arterial pressure (MAP, measured by Finapres), central venous pressure (CVP), stroke volume (SV, Doppler), and forearm blood flow (FBF, plethysmography) were determined during lower body negative pressure (LBNP). The carotid baroreflex (CBR) function was assessed using a train of pulsatile neck pressure (NP) and suction, and the aortic baroreflex control of HR was assessed during steady-state phenylephrine (PE) infusion superimposed by LBNP and NP to counteract the PE increased CVP and carotid sinus pressure, respectively. RESULTS: Active physical deconditioning significantly decreased maximal oxygen uptake (-7%) and LBNP tolerance (-13%) without a change in baseline hemodynamics. Plasma volume (-3% at P = 0.135), determined by Evans Blue dilution, and blood volume (-4% at P = 0.107) were not significantly altered. During LBNP -20 to -50 torr, there was a significantly greater drop of SV per unit decrease in CVP in the post- (14.7 +/- 1.6%/mm Hg) than predeconditioning (11.2 +/- 0.7%/mm Hg) test accompanied by a greater tachycardia. Deconditioning increased the aortic baroreflex sensitivity (pre vs post: -0.61 +/- 0.12 vs -0.84 +/- 0.14 bpm.mm-1 Hg, P = 0.009) and the slope of forearm vascular resistance (calculated from [MAP-CVP]/FBF) to CVP (-2.75 +/- 0.26 vs -4.94 +/- 0.97 PRU/mm Hg, P = 0.086). However, neither the CBR-HR (-0.28 +/- 0.03 VS -0.39 +/- 0.10 bpm.mm-1 Hg) nor the CBR-MAP (-0.37 +/- 0.16 vs -0.25 +/- 0.07 mm Hg/mm Hg) gains were statistically different between pre- and postdeconditioning. CONCLUSIONS: We concluded that the functional modification of the cardiac pressure

  6. Physical Activity to Improve Erectile Function

    DEFF Research Database (Denmark)

    Gerbild, Helle Nygaard; Larsen, Camilla Marie; Areskoug Josefsson, Kristina

    2018-01-01

    , and metabolic syndrome. Physical activity (PA) has proved to be a protective factor against erectile problems, and it has been shown to improve erectile function for men affected by vascular ED. This systematic review estimated the levels of PA needed to decrease ED for men with physical inactivity, obesity......Introduction The leading cause of erectile dysfunction (ED) is arterial dysfunction, with cardiovascular disease as the most common comorbidity. Therefore, ED is typically linked to a web of closely interrelated cardiovascular risk factors such as physical inactivity, obesity, hypertension......, hypertension, metabolic syndrome, and/or manifest cardiovascular diseases. Aim To provide recommendations of levels of PA needed to decrease ED for men with physical inactivity, obesity, hypertension, metabolic syndrome, and/or cardiovascular diseases. Methods In accord with the Preferred Reporting Items...

  7. Influence of denture treatment on brain function activity

    Directory of Open Access Journals (Sweden)

    Toshio Hosoi

    2011-02-01

    In this study, it was revealed that brain function activity was enhanced by the improvement of complete dentures, and by wearing partial dentures. Not only denture function improvement but also brain functional activation was achieved in elderly denture wearers at risk of brain activity deterioration.

  8. Dimer and cluster approach for the evaluation of electronic couplings governing charge transport: Application to two pentacene polymorphs

    Energy Technology Data Exchange (ETDEWEB)

    Canola, Sofia; Pecoraro, Claudia; Negri, Fabrizia

    2016-10-20

    Hole transport properties are modeled for two polymorphs of pentacene: the single crystal polymorph and the thin film polymorph relevant for organic thin-film transistor applications. Electronic couplings are evaluated in the standard dimer approach but also considering a cluster approach in which the central molecule is surrounded by a large number of molecules quantum-chemically described. The effective electronic couplings suitable for the parametrization of a tight-binding model are derived either from the orthogonalization scheme limited to HOMO orbitals and from the orthogonalization of the full basis of molecular orbitals. The angular dependent mobilities estimated for the two polymorphs using the predicted pattern of couplings display different anisotropy characteristics as suggested from experimental investigations.

  9. Effect of In Situ Annealing Treatment on the Mobility and Morphology of TIPS-Pentacene-Based Organic Field-Effect Transistors

    Science.gov (United States)

    Yang, Fuqiang; Wang, Xiaolin; Fan, Huidong; Tang, Ying; Yang, Jianjun; Yu, Junsheng

    2017-08-01

    In this work, organic field-effect transistors (OFETs) with a bottom gate top contact structure were fabricated by using a spray-coating method, and the influence of in situ annealing treatment on the OFET performance was investigated. Compared to the conventional post-annealing method, the field-effect mobility of OFET with 60 °C in situ annealing treatment was enhanced nearly four times from 0.056 to 0.191 cm2/Vs. The surface morphologies and the crystallization of TIPS-pentacene films were characterized by optical microscope, atomic force microscope, and X-ray diffraction. We found that the increased mobility was mainly attributed to the improved crystallization and highly ordered TIPS-pentacene molecules.

  10. Effects of V2O5/Au bi-layer electrodes on the top contact Pentacene-based organic thin film transistors

    Science.gov (United States)

    Borthakur, Tribeni; Sarma, Ranjit

    2017-05-01

    Top-contact Pentacene-based organic thin film transistors (OTFTs) with a thin layer of Vanadium Pent-oxide between Pentacene and Au layer are fabricated. Here we have found that the devices with V2O5/Au bi-layer source-drain electrode exhibit better field-effect mobility, high on-off ratio, low threshold voltage and low sub-threshold slope than the devices with Au only. The field-effect mobility, current on-off ratio, threshold voltage and sub-threshold slope of V2O5/Au bi-layer OTFT estimated from the device with 15 nm thick V2O5 layer is .77 cm2 v-1 s-1, 7.5×105, -2.9 V and .36 V/decade respectively.

  11. Enhancement of Electrical Conductance for Pentacene Thin Film Transistor by Controlling an Initial Layer-by-Layer Growth Mode Directly on SiO2 Insulator

    Science.gov (United States)

    Qi, Qiong; Jiang, Yeping; Yu, Aifang; Qiu, Xiaohui; Jiang, Chao

    2009-04-01

    Initial nucleation and growth of pentacene films on various pre-cleaning treated SiO2 gate insulators were systematically examined by atomic force microscope. The performance of fabricated pentacene thin film transistor devices was found to be highly related to the initial film growth modes. In contrast to the film in the three-dimensional island-like growth mode on SiO2 under an organic cleaning process, a layer-by-layer initial growth mode occurred on the SiO2 insulator cleaned with ammonia solution which has shown much improved electrical properties of the thin film transistors. Field effect mobility of the thin film transistor devices could be achieved as high as 1.0 cm2 V-1 s-1 on the bared SiO2/Si substrate and the on/off ratio was over 106. The enhanced electrical conductance was further confirmed by an electrostatic force microscopic observation of quantized electrical potentials via charge-injection to the submonolayer pentacene islands with layer-by-layer growth mode.

  12. Benzo[4,5]cyclohepta[1,2-b]fluorene: an isomeric motif for pentacene containing linearly fused five-, six- and seven-membered rings

    KAUST Repository

    Yang, Xuejin

    2016-06-07

    Benzo[4,5]cyclohepta[1,2-b]fluorene (5a), a new π-conjugated polycyclic hydrocarbon containing linearly fused six-, five-, six-, seven- and six-membered rings (C6-C5-C6-C7-C6), was designed and its stable derivatives 5b and 5c were synthesized. With 22 π electrons, 5a is an isomer of pentacene with quinoidal, dipolar ionic and diradical resonance forms. Molecules 5b and 5c were experimentally investigated with cyclic voltammetry, electronic absorption spectroscopy and X-ray crystallographic analysis, and theoretically studied by calculating the NICS value, diradical character and dipole moment. A comparison of 5a–c with pentacene and other pentacene analogues containing linearly fused five- or seven- membered rings was also conducted and discussed. It was found that 5b behaved as a p-type organic semiconductor in solution-processed thin film transistors with field effect mobility of up to 0.025 cm2/Vs.

  13. Activation of different cerebral functional regions following ...

    African Journals Online (AJOL)

    Methods and Materials: 30 healthy volunteers were randomly allocated into two groups, one group received acupuncture at KI3 and LR3, the other only acupuncture ... Key words: acupoint combination, acupuncture, resting state, functional magnetic resonance imaging (fMRI), amplitude of low-frequency fluctuation (ALFF), ...

  14. activation parameters and excess thermodyanamic functions of ...

    African Journals Online (AJOL)

    ABSTRACT. Experimental values of density and viscosity of N-arylsubstituted hydroxamic acids were evaluated at T = 303.15 K and 313.15 K in acetone-water mixture as a function of their concentration. The properties of solutes were obtained as an intercept of plots C vs η of solutions. Applying these data, viscosity-B-.

  15. Functional imaging of epileptic activity in humans

    OpenAIRE

    Vulliemoz, Serge

    2012-01-01

    Around 20% of patients suffering from epilepsy have medically refractory seizures and epilepsy surgery can offer a cure or at least a significant improvement of their seizures. in well selected patients. A comprehensive work-up combining different imaging techniques is necessary to localise brain regions involved in the epileptic network. Simultaneous ElectroEncephaloGraphy and functional Magnetic Resonance Imaging (EEG-fMRI) is a new technique that allows mapping epileptic networks at a whol...

  16. Pulmonary Function Responses to Active Cycle Breathing ...

    African Journals Online (AJOL)

    Chronic heart failure patients experience restrictive respiratory dysfunction, resulting in alterations of FEV1, FVC and FEV /FVC as demonstrated in exercise 1 intolerance, dyspnoea and poor quality of life (QoL). Active Cycle of Breathing Techniques (ACBT) is traditionally used by Physiotherapists in the management of ...

  17. Graves' disease: thyroid function and immunologic activity

    International Nuclear Information System (INIS)

    Gossage, A.A.; Crawley, J.C.; Copping, S.; Hinge, D.; Himsworth, R.L.

    1982-01-01

    Patients with Graves' disease were studied for two years during and after a twelve-month course of treatment. Disease activity was determined by repeated measurements of thyroidal uptake of [/sup 99m/Tc]pertechnetate during tri-iodothyronine administration. These in-vivo measurements of thyroid stimulation were compared with the results of in-vitro assays of Graves, immunoglobulin (TSH binding inhibitory activity--TBIA). There was no correlation between the thyroid uptake and TBIA on diagnosis. Pertechnetate uptake and TBIA both declined during the twelve months of antithyroid therapy. TBIA was detectable in sera from 19 of the 27 patients at diagnosis; in 11 of these 19 patients there was a good correlation (p less than 0.05) throughout the course of their disease between the laboratory assay of the Graves, immunoglobulin and the thyroid uptake. Probability of recurrence can be assessed but sustained remission of Graves' disease after treatment cannot be predicted from either measurement alone or in combination

  18. Assessing physical function and physical activity in patients with CKD.

    Science.gov (United States)

    Painter, Patricia; Marcus, Robin L

    2013-05-01

    Patients with CKD are characterized by low levels of physical functioning, which, along with low physical activity, predict poor outcomes in those treated with dialysis. The hallmark of clinical care in geriatric practice and geriatric research is the orientation to and assessment of physical function and functional limitations. Although there is increasing interest in physical function and physical activity in patients with CKD, the nephrology field has not focused on this aspect of care. This paper provides an in-depth review of the measurement of physical function and physical activity. It focuses on physiologic impairments and physical performance limitations (impaired mobility and functional limitations). The review is based on established frameworks of physical impairment and functional limitations that have guided research in physical function in the aging population. Definitions and measures for physiologic impairments, physical performance limitations, self-reported function, and physical activity are presented. On the basis of the information presented, recommendations for incorporating routine assessment of physical function and encouragement for physical activity in clinical care are provided.

  19. Approximation results for neural network operators activated by sigmoidal functions.

    Science.gov (United States)

    Costarelli, Danilo; Spigler, Renato

    2013-08-01

    In this paper, we study pointwise and uniform convergence, as well as the order of approximation, for a family of linear positive neural network operators activated by certain sigmoidal functions. Only the case of functions of one variable is considered, but it can be expected that our results can be generalized to handle multivariate functions as well. Our approach allows us to extend previously existing results. The order of approximation is studied for functions belonging to suitable Lipschitz classes and using a moment-type approach. The special cases of neural network operators activated by logistic, hyperbolic tangent, and ramp sigmoidal functions are considered. In particular, we show that for C(1)-functions, the order of approximation for our operators with logistic and hyperbolic tangent functions here obtained is higher with respect to that established in some previous papers. The case of quasi-interpolation operators constructed with sigmoidal functions is also considered. Copyright © 2013 Elsevier Ltd. All rights reserved.

  20. Antibacterial and antioxidative activity of O-amine functionalized chitosan.

    Science.gov (United States)

    Tamer, Tamer M; Hassan, Mohamed A; Omer, Ahmed M; Valachová, Katarína; Eldin, Mohamed S Mohy; Collins, Maurice N; Šoltés, Ladislav

    2017-08-01

    Cinnamaldehyde was immobilized to O-amine functionalized chitosan via a coupling reaction. Fourier transform infrared spectroscopy confirmed N-cinnamyl substitution. Wetting analyses demonstrate more hydrophobicity in the N-cinnamyl substituted O-amine functionalized chitosan compared to chitosan or unsubstituted O-amine functionalized chitosan. Thermal gravimetric analysis and differential scanning calorimetry demonstrates that the prepared N-cinnamyl substituted O-amine functionalized chitosan exhibits higher thermostability than unmodified chitosan at temperatures in which polysaccharides are commonly stored and utilised. The N-cinnamyl substituted O-amine functionalized chitosan, against four different bacteria strains [two gram-positive (Staphylococcus aureus and Bacillus cereus) and two gram-negative (Escherichia coli and Pseudomonas aeruginosa)], displays promotion of inhibition activity against these bacterial strains. Finally, the antioxidative activity of the N-cinnamyl substituted O-amine functionalized chitosan was compared with those activities of chitosan and O-amine functionalized chitosan. This was evaluated by uninhibited and inhibited hyaluronan degradation and ABTS assay. The N-cinnamyl substituted O-amine functionalized chitosan shows a lower activity towards donating a hydrogen radical compared to chitosan or O-amine functionalized chitosan. On the other hand, the N-cinnamyl substituted O-amine functionalized chitosan exhibited a higher ability to scavenge the ABTS + cation radical compared to chitosan and O-amine functionalized chitosan. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Ramiprilate inhibits functional matrix metalloproteinase activity in Crohn's disease fistulas

    DEFF Research Database (Denmark)

    Efsen, Eva; Saermark, Torben; Hansen, Alastair

    2011-01-01

    from six controls were also included. Total functional MMP activity was measured by a high-pressure liquid chromatography (HPLC)-based, fluorogenic MMP-substrate cleavage assay, and the specific activity of MMP-2, -3 and -9 by the MMP Biotrak Activity Assay. The MMP inhibitors comprised ethylene...

  2. Influence of orientation mismatch on charge transport across grain boundaries in tri-isopropylsilylethynyl (TIPS) pentacene thin films.

    Science.gov (United States)

    Steiner, Florian; Poelking, Carl; Niedzialek, Dorota; Andrienko, Denis; Nelson, Jenny

    2017-05-03

    We present a multi-scale model for charge transport across grain boundaries in molecular electronic materials that incorporates packing disorder, electrostatic and polarisation effects. We choose quasi two-dimensional films of tri-isopropylsilylethynyl pentacene (TIPS-P) as a model system representative of technologically relevant crystalline organic semiconductors. We use atomistic molecular dynamics, with a force-field specific for TIPS-P, to generate and equilibrate polycrystalline two-dimensional thin films. The energy landscape is obtained by calculating contributions from electrostatic interactions and polarization. The variation in these contributions leads to energetic barriers between grains. Subsequently, charge transport is simulated using a kinetic Monte-Carlo algorithm. Two-grain systems with varied mutual orientation are studied. We find relatively little effect of long grain boundaries due to the presence of low impedance pathways. However, effects could be more pronounced for systems with limited inter-grain contact areas. Furthermore, we present a lattice model to generalize the model for small molecular systems. In the general case, depending on molecular architecture and packing, grain boundaries can result in interfacial energy barriers, traps or a combination of both with qualitatively different effects on charge transport.

  3. Hybrid independent component analysis by adaptive LUT activation function neurons.

    Science.gov (United States)

    Fiori, Simone

    2002-01-01

    The aim of this paper is to present an efficient implementation of unsupervised adaptive-activation function neurons dedicated to one-dimensional probability density estimation, with application to independent component analysis. The proposed implementation is a computationally light improvement to adaptive pseudo-polynomial neurons, recently presented in Fiori, S. (2000a). Blind signal processing by the adaptive activation function neurons. Neural Networks, 13(6), 597-611, and is based upon the concept of 'look-up table' (LUT) neurons.

  4. Activity limitations and factors influencing functional outcome of ...

    African Journals Online (AJOL)

    EB

    2013-09-03

    Sep 3, 2013 ... It further underscores the administration of a functional rating scale on admission in order to aggressively manage activity limitations. .... rating scale (presented with intervals of 5 points) of this tool allows for the measurement of the ..... function and life satisfaction after stroke. Journal of the American Heart ...

  5. Physical Activity and Cognitive Functioning of Children: A Systematic Review

    Directory of Open Access Journals (Sweden)

    Ilona Bidzan-Bluma

    2018-04-01

    Full Text Available Childhood is an important and sensitive period for cognitive development. There is limited published research regarding the relationship between sports and cognitive functions in children. We present studies that demonstrate the influence of physical activity on health, especially a positive correlation between sports and cognitive functions. The keywords “children, cognition, cognitive function, physical activity, and brain” were searched for using PsycInfo, Medline, and Google Scholar, with publication dates ranging from January 2000 to November 2017. Of the 617 results, 58 articles strictly connected to the main topics of physical activity and cognitive functioning were then reviewed. The areas of attention, thinking, language, learning, and memory were analyzed relative to sports and childhood. Results suggest that engaging in sports in late childhood positively influences cognitive and emotional functions. There is a paucity of publications that investigate the impact of sports on pre-adolescents’ cognitive functions, or explore which cognitive functions are developed by which sporting disciplines. Such knowledge would be useful in developing training programs for pre-adolescents, aimed at improving cognitive functions that may guide both researchers and practitioners relative to the wide range of benefits that result from physical activity.

  6. Immune activation is associated with decreased thymic function in ...

    African Journals Online (AJOL)

    Background: Reduced thymic function causes poor immunological reconstitution in human immunodeficiency virus (HIV)-positive patients on combined antiretroviral therapy (cART). The association between immune activation and thymic function in asymptomatic HIVpositive treatment-naive individuals has thus far not been ...

  7. The contact activation proteins: a structure/function overview

    NARCIS (Netherlands)

    Meijers, J. C.; McMullen, B. A.; Bouma, B. N.

    1992-01-01

    In recent years, extensive knowledge has been obtained on the structure/function relationships of blood coagulation proteins. In this overview, we present recent developments on the structure/function relationships of the contact activation proteins: factor XII, high molecular weight kininogen,

  8. Intraoperative Functional Ultrasound Imaging of Human Brain Activity

    OpenAIRE

    Imbault, Marion; Chauvet, Dorian; Gennisson, Jean-Luc; Capelle, Laurent; Tanter, Mickael

    2017-01-01

    International audience; The functional mapping of brain activity is essential to perform optimal glioma surgery and to minimize the risk of postoperative deficits. We introduce a new, portable neuroimaging modality of the human brain based on functional ultrasound (fUS) for deep functional cortical mapping. Using plane-wave transmissions at an ultrafast frame rate (1 kHz), fUS is performed during surgery to measure transient changes in cerebral blood volume with a high spatiotemporal resoluti...

  9. Barrier formation at organic interfaces in a Cu(100)-benzenethiolate-pentacene heterostructure

    DEFF Research Database (Denmark)

    Betti, M.G.; Kanjilal, A.; Mariani, C.

    2008-01-01

    molecular dipoles, and interface screening as a function of coverage. Despite the different nature of the two interfaces, our model provides a unified explanation for the work-function changes at both junctions and enables us to determine the benzenethiolate orientation as a function of coverage....

  10. Physical Activity Level, Nutritional Intake, Functional Status and ...

    African Journals Online (AJOL)

    Background: Participation in physical activity (PA) and healthy nutrition are important factors that affects muscle and bone strength and the resultant functioning in the activities of daily living (ADL) skills including the overall quality of life (QoL) of geriatric individuals. However, the relationships between all these parameters ...

  11. Activity limitations and factors influencing functional outcome of ...

    African Journals Online (AJOL)

    Results: The mean Barthel Index scores on admission and at discharge were 58.85 and 81.59 respectively. A significant improvement was noted in the ... It further underscores the administration of a functional rating scale on admission in order to aggressively manage activity limitations. Key words: stroke, activity limitations, ...

  12. Pentacene thin-film transistors and inverters with plasma-enhanced atomic-layer-deposited Al2O3 gate dielectric

    International Nuclear Information System (INIS)

    Koo, Jae Bon; Lim, Jung Wook; Kim, Seong Hyun; Yun, Sun Jin; Ku, Chan Hoe; Lim, Sang Chul; Lee, Jung Hun

    2007-01-01

    The performances of pentacene thin-film transistor with plasma-enhanced atomic-layer-deposited (PEALD) 150 nm thick Al 2 O 3 dielectric are reported. Saturation mobility of 0.38 cm 2 /V s, threshold voltage of 1 V, subthreshold swing of 0.6 V/decade, and on/off current ratio of about 10 8 have been obtained. Both depletion and enhancement mode inverter have been realized with the change of treatment method of hexamethyldisilazane on PEALD Al 2 O 3 gate dielectric. Full swing depletion mode inverter has been demonstrated at input voltages ranging from 5 V to - 5 V at supply voltage of - 5 V

  13. Functional connectivity and brain activation: a synergistic approach.

    Science.gov (United States)

    Tomasi, Dardo; Wang, Ruiliang; Wang, Gene-Jack; Volkow, Nora D

    2014-10-01

    Traditional functional magnetic resonance imaging (fMRI) studies exploit endogenous brain activity for mapping brain activation during "periodic" cognitive/emotional challenges or brain functional connectivity during the "resting state". Previous studies demonstrated that these approaches provide a limited view of brain function which can be complemented by each other. We hypothesized that graph theory functional connectivity density (FCD) mapping would demonstrate regional FCD decreases between resting-state scan and a continuous "task-state" scan. Forty-five healthy volunteers underwent functional connectivity MRI during resting-state as well as a continuous visual attention task, and standard fMRI with a blocked version of the visual attention task. High-resolution data-driven FCD mapping was used to measure task-related connectivity changes without a priori hypotheses. Results demonstrate that task performance was associated with FCD decreases in brain regions weakly activated/deactivated by the task. Furthermore, a pronounced negative correlation between blood oxygen level-dependent-fMRI activation and task-related FCD decreases emerged across brain regions that also suggest the disconnection of task-irrelevant networks during task performance. The correlation between improved accuracy and stronger FCD decreases further suggests the disconnection of task-irrelevant networks during task performance. Functional connectivity can potentiate traditional fMRI studies and offer a more complete picture of brain function. Published by Oxford University Press 2013. This work is written by (a) US Government employee(s) and is in the public domain in the US.

  14. A (time-dependent) density functional theory study of the optoelectronic properties of bis-triisopropylsilylethynyl-functionalized acenes

    International Nuclear Information System (INIS)

    Malloci, G.; Cappellini, G.; Mulas, G.; Mattoni, A.

    2013-01-01

    We report a comparative study of the optoelectronic properties of small acenes (benzene, anthracene, and pentacene) and their bis-triisopropylsilylethynyl (TIPS) functionalized counterparts. We computed the fundamental gap using density functional theory (DFT) in the framework of the ΔSCF scheme, and the optical absorption spectra by means of time-dependent DFT. Upon TIPS functionalization we observed a lowering of the ionization energy and a rise of the electron affinity; we consequently predict a systematic reduction of the fundamental electronic gap which decreases from ∼ 40% for benzene to ∼ 16% for pentacene. This trend is reflected in the computed optical absorption spectra: for all TIPS-molecules the onset of absorption is red-shifted as compared to their plain precursors. In the case of TIPS-pentacene, in particular, the computed spectrum agrees with the available experimental data. - Highlights: • We evaluate the effect of triisopropylsilylethynyl (TIPS)-substitution on acenes. • We compared the fundamental gap and the optical absorption as a function of size. • We found a general gap reduction following TIPS functionalization. • The gap reduction decreases at increasing size, from 40% for n = 1 to 16% for n = 5. • The onset of absorption is red-shifted as compared to TIPS precursors

  15. Physical activity and sexual function in middle-aged women

    Directory of Open Access Journals (Sweden)

    Patrícia Uchôa Leitão Cabral

    2014-02-01

    Full Text Available Objective To investigate the relationship between physical activity level and sexual function in middle-aged women. Methods A cross-sectional study with a sample of 370 middle-aged women (40-65 years old, treated at public health care facilities in a Brazilian city. A questionnaire was used containing enquiries on sociodemographic, clinical and behavioral characteristics: the International Physical Activity Questionnaire (IPAQ, short form, and the Female Sexual Function Index (FSFI. Results The average age of the women studied was 49.8 years (± 8.1, 67% of whom exhibited sexual dysfunction (FSFI ≤ 26.55. Sedentary women had a higher prevalence (78.9% of sexual dysfunction when compared to active (57.6% and moderately active (66.7% females (p = 0.002. Physically active women obtained higher score in all FSFI domains (desire, arousal, lubrication, orgasm, satisfaction and pain and total FSFI score (20.9, indicating better sexual function than their moderately active (18.8 and sedentary (15.6 counterparts (p <0.05. Conclusion Physical activity appears to influence sexual function positively in middle-aged women.

  16. Effects of functional physical activity on the maintenance of motor function in Alzheimer’s disease

    OpenAIRE

    Fajersztajn, Laís; Cordeiro, Renata Cereda; Andreoni, Solange; Garcia, Jacqueline Takayanagi

    2008-01-01

    Abstract It is widely known that older adults, even frail individuals, can improve their physical function using appropriately targeted exercise. Nevertheless, older adults with Alzheimer's disease (AD) have been excluded from the majority of studies on exercise. The functional-task physical activity program is based on activities of daily living, and may be suited for elderly people with AD because it focuses on the maintenance and stimulation of preserved abilities. In addition, session cos...

  17. Cortical language activation in aphasia: a functional MRI study

    International Nuclear Information System (INIS)

    Xu Xiaojun; Zhang Minming; Shang Desheng; Wang Qidong; Luo Benyan

    2004-01-01

    Objective: To investigate the differences of the underlying neural basis of language processing between normal subjects and aphasics, and to study the feasibility for functional magnetic resonance imaging (fMRI) in examining the cortical language activation in clinical aphasics. Methods: fMRI was used to map language network in 6 normal subjects and 3 patients with aphasia who were in the stage of recovery from acute stroke. The participants performed word generation task during fMRI scanning, which measured the signal changes associated with regional neural activity induced by the task. These signal changes were processed to statistically generate the activation map that represented the language area. Results: In normal subjects, a distributed language network was activated. Activations were present in the frontal, temporal, parietal and occipital regions in normal group. In the patient group, however, no activation was showed in the left inferior frontal gyrus whether or not the patient had lesion in the left frontal lobe. Two patients showed activations in some right hemisphere regions where no activation appeared in normal subjects. Conclusion: The remote effect of focal lesion and functional redistribution or reorganization was found in aphasic patients. fMRI was useful in evaluating the language function in aphasic patients. (authors)

  18. Ramiprilate inhibits functional matrix metalloproteinase activity in Crohn's disease fistulas

    DEFF Research Database (Denmark)

    Efsen, Eva; Saermark, Torben; Hansen, Alastair

    2011-01-01

    Increased expression of matrix metalloproteinase (MMP)-2, -3 and -9 has been demonstrated in Crohn's disease fistulas, but it is unknown whether these enzymes are biologically active and represent a therapeutic target. Therefore, we investigated the proteolytic activity of MMPs in fistula tissue...... from six controls were also included. Total functional MMP activity was measured by a high-pressure liquid chromatography (HPLC)-based, fluorogenic MMP-substrate cleavage assay, and the specific activity of MMP-2, -3 and -9 by the MMP Biotrak Activity Assay. The MMP inhibitors comprised ethylene......-9.83) compared with non-Crohn's fistulas, [0.32 ng/ml, range 0-2.66, (p MMP-9 activity [0.64 ng/ml, range 0-5.66 and 0.17 ng/ml, range 0-1.1, respectively (p MMP activity level by 42% and suppressed the specific MMP-3...

  19. Effects of functional physical activity on the maintenance of motor function in Alzheimer's disease

    Directory of Open Access Journals (Sweden)

    Laís Fajersztajn

    Full Text Available Abstract It is widely known that older adults, even frail individuals, can improve their physical function using appropriately targeted exercise. Nevertheless, older adults with Alzheimer's disease (AD have been excluded from the majority of studies on exercise. The functional-task physical activity program is based on activities of daily living, and may be suited for elderly people with AD because it focuses on the maintenance and stimulation of preserved abilities. In addition, session costs are substantially reduced by adopting a group approach. Furthermore, the group approach may improve the social interaction of the demented patient. Objectives: To determine whether a functional-task physical activity program in groups can maintain motor function in elderly with AD. Methods: 10 elderly diagnosed with mild or moderate AD were assigned into one of two groups: subjects with and without intervention. The intervention consisted of a 12-week function-task physical activity program in groups. Measurements: activities of daily living (Katz and Lawton & Brody questionnaires, mobility (Timed Up and Go Test, Timed Up and Go manual Test and Timed Up and Go Cognitive Test, cognition (Mini-Mental State Examination, behavioral disturbances (Neuropsychiatric Inventory I-brief and functional balance (Berg Balance Scale. Results: A statistically significant difference between the two groups was found regarding the functional balance mean change measured by Berg scale score (p=0.046. A significant improvement of 1.60 points (95%CI[0.22;2.98] was observed in the intervention group on this scale, while the non-intervention group showed -0.40 points (95%CI[-1.78;0.98], no change. Conclusions: It is possible to treat mild and moderate Alzheimer's patients using a group approach. The functional task physical activity program was efficient in functional balance improvement and also appeared to prevent mobility decline.

  20. Optimized circuit design for flexible 8-bit RFID transponders with active layer of ink-jet printed small molecule semiconductors

    NARCIS (Netherlands)

    Kjellander, B.K.C.; Smaal, W.T.T.; Myny, K.; Genoe, J.; Dehaene, W.; Heremans, P.; Gelinck, G.H.

    2013-01-01

    We ink-jet print a blend of 6,13-bis(triisopropyl-silylethynyl)pentacene and polystyrene as the active layer for flexible circuits. The discrete ink-jet printed transistors exhibit a saturation mobility of 0.5 cm2 V -1 s-1. The relative spread in transistor characteristics can be very large. This

  1. Functional analysis of Ficolin-3 mediated complement activation

    DEFF Research Database (Denmark)

    Hein, Estrid; Honoré, Christian; Skjoedt, Mikkel-Ole

    2010-01-01

    Ficolin-3 mediated complement activation that could be applicable for research and clinical use. Bovine serum albumin (BSA) was acetylated (acBSA) and chosen as a solid phase ligand for Ficolins in microtiter wells. Binding of Ficolins on acBSA was evaluated, as was functional complement activation...... was applied to the samples that inhibited interference from the classical pathway due to the presence of anti-BSA antibodies in some sera. We describe a novel functional method for measuring complement activation mediated by Ficolin-3 in human serum up to the formation of TCC. The assay provides......The recognition molecules of the lectin complement pathway are mannose-binding lectin and Ficolin -1, -2 and -3. Recently deficiency of Ficolin-3 was found to be associated with life threatening infections. Thus, we aimed to develop a functional method based on the ELISA platform for evaluating...

  2. Synthesis and Antibacterial Activity of Antibiotic-Functionalized Graphite Nanofibers

    Directory of Open Access Journals (Sweden)

    Madeline Rotella

    2015-01-01

    Full Text Available Surface functionalization of nanomaterials is an area of current investigation that supports the development of new biomaterials for applications in biology and medicine. Herein we describe the synthesis, characterization, and antibacterial properties of the first examples of antibiotic-labeled graphitic carbon nanofibers (GCNFs covalently functionalized with aminoglycoside and quinolone antibiotics. Ruthenium tetroxide oxidation of herringbone GCNFs gave higher amounts of surface carboxyl groups than previous methods. These carboxyl groups served as sites of attachment for antibiotics by acyl substitution. Bioassay of these novel, functionalized GCNFs using serial dilution and optical density methods demonstrated that antibiotic-labeled GCNFs possess significant antibacterial activity against Pseudomonas aeruginosa. The activity we observe for aminoglycoside-functionalized GCNFs suggests a membranolytic mechanism of action.

  3. Multivariate neural network operators with sigmoidal activation functions.

    Science.gov (United States)

    Costarelli, Danilo; Spigler, Renato

    2013-12-01

    In this paper, we study pointwise and uniform convergence, as well as order of approximation, of a family of linear positive multivariate neural network (NN) operators with sigmoidal activation functions. The order of approximation is studied for functions belonging to suitable Lipschitz classes and using a moment-type approach. The special cases of NN operators, activated by logistic, hyperbolic tangent, and ramp sigmoidal functions are considered. Multivariate NNs approximation finds applications, typically, in neurocomputing processes. Our approach to NN operators allows us to extend previous convergence results and, in some cases, to improve the order of approximation. The case of multivariate quasi-interpolation operators constructed with sigmoidal functions is also considered. Copyright © 2013 Elsevier Ltd. All rights reserved.

  4. Swell activated chloride channel function in human neutrophils

    Energy Technology Data Exchange (ETDEWEB)

    Salmon, Michael D. [Leukocyte and Ion Channel Research Laboratory, School of Health and Biosciences, University of East London, Stratford Campus, London E15 4LZ (United Kingdom); Ahluwalia, Jatinder, E-mail: j.ahluwalia@uel.ac.uk [Leukocyte and Ion Channel Research Laboratory, School of Health and Biosciences, University of East London, Stratford Campus, London E15 4LZ (United Kingdom)

    2009-04-17

    Non-excitable cells such as neutrophil granulocytes are the archetypal inflammatory immune cell involved in critical functions of the innate immune system. The electron current generated (I{sub e}) by the neutrophil NADPH oxidase is electrogenic and rapidly depolarises the membrane potential. For continuous function of the NADPH oxidase, I{sub e} has to be balanced to preserve electroneutrality, if not; sufficient depolarisation would prevent electrons from leaving the cell and neutrophil function would be abrogated. Subsequently, the depolarisation generated by the neutrophil NADPH oxidase I{sub e} must be counteracted by ion transport. The finding that depolarisation required counter-ions to compensate electron transport was followed by the observation that chloride channels activated by swell can counteract the NADPH oxidase membrane depolarisation. In this mini review, we discuss the research findings that revealed the essential role of swell activated chloride channels in human neutrophil function.

  5. Activated and deactivated functional brain areas in the Deqi state

    OpenAIRE

    Huang, Yong; Zeng, Tongjun; Zhang, Guifeng; Li, Ganlong; Lu, Na; Lai, Xinsheng; Lu, Yangjia; Chen, Jiarong

    2012-01-01

    We compared the activities of functional regions of the brain in the Deqi versus non-Deqi state, as reported by physicians and subjects during acupuncture. Twelve healthy volunteers received sham and true needling at the Waiguan (TE5) acupoint. Real-time cerebral functional MRI showed that compared with non-sensation after sham needling, true needling activated Brodmann areas 3, 6, 8, 9, 10, 11, 13, 20, 21, 37, 39, 40, 43, and 47, the head of the caudate nucleus, the parahippocampal gyrus, th...

  6. Functional magnetic resonance imaging of higher brain activity

    International Nuclear Information System (INIS)

    Cui He; Wang Yunjiu; Chen Runsheng; Tang Xiaowei.

    1996-01-01

    Functional magnetic resonance images (fMRIs) exhibit small differences in the magnetic resonance signal intensity in positions corresponding to focal areas of brain activation. These signal are caused by variation in the oxygenation state of the venous vasculature. Using this non-invasive and dynamic method, it is possible to localize functional brain activation, in vivo, in normal individuals, with an accuracy of millimeters and a temporal resolution of seconds. Though a series of technical difficulties remain, fMRI is increasingly becoming a key method for visualizing the working brain, and uncovering the topographical organization of the human brain, and understanding the relationship between brain and the mind

  7. Homogeneous Crystallization of Micro-DispensedTIPS-Pentacene Using a Two-Solvent System toEnable Printed Inverters on Foil Substrates

    Directory of Open Access Journals (Sweden)

    Indranil Bose

    2015-08-01

    Full Text Available We report on a micro-dispensing system for 6,13-Bis(triisopropylsilylethynylpentacene (TIPS-pentacene to enable homogenous crystallization and uniform filmmorphology of the dispensed droplets using a two-solvent mixture along with the use of aninsulating binder. This solution composition results in a controlled evaporation of the dropletin ambient air such that the Marangoni flow counteracts the outward convective flow toenable uniform radial crystal growth from the edge towards the center of the drops.The consequence of this process is the high degree of uniformity in the crystallization of thedrops, which results in a reduction in the performance spread of the organic field effecttransistors (OFET created using this process. The addition of the insulating binder furtherimproves the reduction in the spread of the results as a trade-off to the reduction in mobilityof the transistors. The transfer curves of the OFETs show a tight grouping due to thecontrolled self-alignment of the TIPS-pentacene crystals; this repeatability was furtherhighlighted by fabricating p-type inverters with driver to load ratios of 8:1, wherein theoutput inverter curves were also grouped tightly while exhibiting a gain of greater than 4 inthe switching region. Therefore, the reliability and repeatability of this process justifies itsuse to enable large area solution-processed printed circuits at the cost of reduced mobility.

  8. Brain Activity and Functional Connectivity Associated with Hypnosis.

    Science.gov (United States)

    Jiang, Heidi; White, Matthew P; Greicius, Michael D; Waelde, Lynn C; Spiegel, David

    2017-08-01

    Hypnosis has proven clinical utility, yet changes in brain activity underlying the hypnotic state have not yet been fully identified. Previous research suggests that hypnosis is associated with decreased default mode network (DMN) activity and that high hypnotizability is associated with greater functional connectivity between the executive control network (ECN) and the salience network (SN). We used functional magnetic resonance imaging to investigate activity and functional connectivity among these three networks in hypnosis. We selected 57 of 545 healthy subjects with very high or low hypnotizability using two hypnotizability scales. All subjects underwent four conditions in the scanner: rest, memory retrieval, and two different hypnosis experiences guided by standard pre-recorded instructions in counterbalanced order. Seeds for the ECN, SN, and DMN were left and right dorsolateral prefrontal cortex, dorsal anterior cingulate cortex (dACC), and posterior cingulate cortex (PCC), respectively. During hypnosis there was reduced activity in the dACC, increased functional connectivity between the dorsolateral prefrontal cortex (DLPFC;ECN) and the insula in the SN, and reduced connectivity between the ECN (DLPFC) and the DMN (PCC). These changes in neural activity underlie the focused attention, enhanced somatic and emotional control, and lack of self-consciousness that characterizes hypnosis. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  9. Evaluation of cardiac function in active and hibernating grizzly bears.

    Science.gov (United States)

    Nelson, O Lynne; McEwen, Margaret-Mary; Robbins, Charles T; Felicetti, Laura; Christensen, William F

    2003-10-15

    To evaluate cardiac function parameters in a group of active and hibernating grizzly bears. Prospective study. 6 subadult grizzly bears. Indirect blood pressure, a 12-lead ECG, and a routine echocardiogram were obtained in each bear during the summer active phase and during hibernation. All measurements of myocardial contractility were significantly lower in all bears during hibernation, compared with the active period. Mean rate of circumferential left ventricular shortening, percentage fractional shortening, and percentage left ventricular ejection fraction were significantly lower in bears during hibernation, compared with the active period. Certain indices of diastolic function appeared to indicate enhanced ventricular compliance during the hibernation period. Mean mitral inflow ratio and isovolumic relaxation time were greater during hibernation. Heart rate was significantly lower for hibernating bears, and mean cardiac index was lower but not significantly different from cardiac index during the active phase. Contrary to results obtained in hibernating rodent species, cardiac index was not significantly correlated with heart rate. Cardiac function parameters in hibernating bears are opposite to the chronic bradycardic effects detected in nonhibernating species, likely because of intrinsic cardiac muscle adaptations during hibernation. Understanding mechanisms and responses of the myocardium during hibernation could yield insight into mechanisms of cardiac function regulation in various disease states in nonhibernating species.

  10. Lifetime Musical Activities and Cognitive Function of the Elderly

    Directory of Open Access Journals (Sweden)

    Alicia Nevriana

    2013-02-01

    Full Text Available Decreasing cognitive function of the elderly is one of the most common problems that might affect their quality of life. Music is an element that is believed to be able to contribute to the quality of life of the elderly. However, whether musical activities that are done throughout the life span related to cognitive function is unclear. In this research, we evaluated the association between lifetime musical activities and cognitive function. Fifty three older adults from three nursing homes in East Jakarta were selected and interviewed regarding their characteristics and lifetime musical activities. Cognitive function was also measured using Mini Mental State Examinaion (MMSE. The results of this preliminary study revealed that a possibility of an association between lifetime musical activities and cognitive function of the elderly was indicated. The result also showed that the participants who were not actively involved in musical activities during their lifetime were twice more likely to develop cognitive function impairment than the elderly who were actively involved in musical activities, after being adjusted by the characteristics. These correlational results suggest the beneficial effect of musical activities throughout the life span on cognitive functioning for the elderly. Penurunan fungsi kognitif merupakan salah satu masalah umum pada lanjut usia yang mampu memengaruhi kualitas hidup mereka. Musik merupakan sebuah elemen yang dipercaya mampu berkontribusi terhadap kualitas hidup mereka. Meski demikian, hubungan antara aktivitas musikal yang dilakukan sepanjang hidup dan fungsi kognitif lansia belum diketahui secara pasti. Pada penelitian ini, hubungan antara aktivitas musikal sepanjang hidup dan fungsi kognitif dievaluasi. Lima puluh tiga lansia penghuni panti tresna werdha di Jakarta Timur dipilih dan diwawancarai terkait karakteristik dan aktivitas musikal sepanjang hidup mereka. Fungsi kognitif juga diukur menggunakan MMSE. Hasil

  11. Functional modifications of macrophage activity after sublethal irradiation

    International Nuclear Information System (INIS)

    Swartz, R.P.

    1982-01-01

    The modifications of macrophage activity following sublethal irradiation, both in vivo and in vitro, were studied using spreading and C3b-receptor-mediated ingestion assays. Nonelicited peritoneal washout cells were examined for changes in activity and selected population characteristics. The cells from irradiated mice were from a resident peritoneal population and not immigrating cells. The macrophage population showed enhanced activity early with a refractory period (24-48) when the macrophages were unresponsive to stimulation by irradiated lymphocytes. The enhanced activity was inversely dose dependent on macrophage. The lymphocytes showed a regulatory function(s) on the time post irradiation at which they were examined. Early lymphocytes exhibited the ability to enhance the activity of normal macrophages while lymphocytes removed 24 hours post irradiation could suppress the activity of already activated macrophages. The effect(s) of the various lymphocyte populations were reproduced with cell-free supernatants which was indicative of the production of lymphokines. Separation on nylon wool columns indicated that the activity resided primarily in the T-cell population of lymphocytes. In vitro irradiation indicated that stimulation of the lymphocytes is macrophage dependent. Additional work indicated that sublethally irradiated macrophages did not inhibit replication of the coccidian protozoon Toxoplasma gondii although they did show increased phagocytosis. Examination of the serum from whole body irradiated mice showed the presence of a postirradiation substance which enhanced the phagocytosis of normal macrophages. It was not present in the serum of normal mice and was not endotoxin

  12. The restless brain: how intrinsic activity organizes brain function.

    Science.gov (United States)

    Raichle, Marcus E

    2015-05-19

    Traditionally studies of brain function have focused on task-evoked responses. By their very nature such experiments tacitly encourage a reflexive view of brain function. While such an approach has been remarkably productive at all levels of neuroscience, it ignores the alternative possibility that brain functions are mainly intrinsic and ongoing, involving information processing for interpreting, responding to and predicting environmental demands. I suggest that the latter view best captures the essence of brain function, a position that accords well with the allocation of the brain's energy resources, its limited access to sensory information and a dynamic, intrinsic functional organization. The nature of this intrinsic activity, which exhibits a surprising level of organization with dimensions of both space and time, is revealed in the ongoing activity of the brain and its metabolism. As we look to the future, understanding the nature of this intrinsic activity will require integrating knowledge from cognitive and systems neuroscience with cellular and molecular neuroscience where ion channels, receptors, components of signal transduction and metabolic pathways are all in a constant state of flux. The reward for doing so will be a much better understanding of human behaviour in health and disease.

  13. Tansig activation function (of MLP network) for cardiac abnormality detection

    Science.gov (United States)

    Adnan, Ja'afar; Daud, Nik Ghazali Nik; Ishak, Mohd Taufiq; Rizman, Zairi Ismael; Rahman, Muhammad Izzuddin Abd

    2018-02-01

    Heart abnormality often occurs regardless of gender, age and races. This problem sometimes does not show any symptoms and it can cause a sudden death to the patient. In general, heart abnormality is the irregular electrical activity of the heart. This paper attempts to develop a program that can detect heart abnormality activity through implementation of Multilayer Perceptron (MLP) network. A certain amount of data of the heartbeat signals from the electrocardiogram (ECG) will be used in this project to train the MLP network by using several training algorithms with Tansig activation function.

  14. Functionally active silicones as modifiers of polyurethane textile ...

    African Journals Online (AJOL)

    Modification of application and service properties of polyurethane textile coatings and cast polyurethane films using polysiloxanes (functionally active silicones) have been studied. Experiments were conducted to investigate the effect of silicon additives on processing, adhesion, water repellence, and resistance to tea and ...

  15. Comparison of Functional Disability with Physical Activity in Patients ...

    African Journals Online (AJOL)

    The objectives of this study were to evaluate the effects of functional disabilities and physical activity in patients with low back pain (LBP) and apparently healthy individuals (AHI).Oswestry Low back Pain disability questionnaire was administered to thirty five (35) subjects drawn from 3 various health facilities in Lagos State.

  16. A new chaotic Hopfield network with piecewise linear activation function

    International Nuclear Information System (INIS)

    Peng-Sheng, Zheng; Wan-Sheng, Tang; Jian-Xiong, Zhang

    2010-01-01

    This paper presents a new chaotic Hopfield network with a piecewise linear activation function. The dynamic of the network is studied by virtue of the bifurcation diagram, Lyapunov exponents spectrum and power spectrum. Numerical simulations show that the network displays chaotic behaviours for some well selected parameters

  17. Functional and catalytic active sites prediction and docking analysis ...

    African Journals Online (AJOL)

    Bioinformatics

    2015-07-01

    Jul 1, 2015 ... African Journal of Biotechnology. Full Length Research Paper. Functional and catalytic active sites prediction and docking analysis of azoreductase enzyme in. Pseudomonas putida with a variety of commercially available azodyes. Bikash Thakuria, Chandra J Singha, Premchand Maisnam and Samrat ...

  18. Human brain activity with functional NIR optical imager

    Science.gov (United States)

    Luo, Qingming

    2001-08-01

    In this paper we reviewed the applications of functional near infrared optical imager in human brain activity. Optical imaging results of brain activity, including memory for new association, emotional thinking, mental arithmetic, pattern recognition ' where's Waldo?, occipital cortex in visual stimulation, and motor cortex in finger tapping, are demonstrated. It is shown that the NIR optical method opens up new fields of study of the human population, in adults under conditions of simulated or real stress that may have important effects upon functional performance. It makes practical and affordable for large populations the complex technology of measuring brain function. It is portable and low cost. In cognitive tasks subjects could report orally. The temporal resolution could be millisecond or less in theory. NIR method will have good prospects in exploring human brain secret.

  19. Intraoperative Functional Ultrasound Imaging of Human Brain Activity.

    Science.gov (United States)

    Imbault, Marion; Chauvet, Dorian; Gennisson, Jean-Luc; Capelle, Laurent; Tanter, Mickael

    2017-08-04

    The functional mapping of brain activity is essential to perform optimal glioma surgery and to minimize the risk of postoperative deficits. We introduce a new, portable neuroimaging modality of the human brain based on functional ultrasound (fUS) for deep functional cortical mapping. Using plane-wave transmissions at an ultrafast frame rate (1 kHz), fUS is performed during surgery to measure transient changes in cerebral blood volume with a high spatiotemporal resolution (250 µm, 1 ms). fUS identifies, maps and differentiates regions of brain activation during task-evoked cortical responses within the depth of a sulcus in both awake and anaesthetized patients.

  20. Functional fitness of older women performing physical activities

    Directory of Open Access Journals (Sweden)

    Tania Rosane Bertoldo Benedetti

    2010-02-01

    Full Text Available Aging is a natural and progressive process and physical activities have been indi-cated as a possibility to minimize its impact and, especially, to maintain the functional capacity of older adults for a longer period of time. The objective of the present study was to analyze modifications in the General Functional Fitness Index (GFFI in older adults participating in a physical activity program for a period of 10 months and to associate the results with different age strata, duration of participation in the program and modifications in physical fitness. The study was conducted on 225 older women (mean age: 69.26, sd=5.685, participating in the Physical Activity and Folk Dance Program for The Elderly of the Sports Center, Universidade Federal de Santa Catarina. Descriptive statistics, Student t-test and analysis of variance (ANOVA were used for analysis of the data. A significant difference (p< 0.01 in GFFI and in the variables agility/balance and coordination (p< 0.01 was observed between March and December 2005. Strength (p=0.323, resistance (p=0,946 and flexibility (p=0.722 did not differ significantly during the period analyzed. In addition, the group performing physical activity for more than 10 years and the group older than 80 years presented the best GFFI in the assessments. Physical activity for older adults might be an important factor to improve and/or maintain functional fitness during the process of aging.

  1. Active Space Dependence in Multiconfiguration Pair-Density Functional Theory.

    Science.gov (United States)

    Sharma, Prachi; Truhlar, Donald G; Gagliardi, Laura

    2018-02-13

    In multiconfiguration pair-density functional theory (MC-PDFT), multiconfiguration self-consistent-field calculations and on-top density functionals are combined to describe both static and dynamic correlation. Here, we investigate how the MC-PDFT total energy and its components depend on the active space choice in the case of the H 2 and N 2 molecules. The active space dependence of the on-top pair density, the total density, the ratio of on-top pair density to half the square of the electron density, and the satisfaction of the virial theorem are also explored. We find that the density and on-top pair density do not change significantly with changes in the active space. However, the on-top ratio does change significantly with respect to active space change, and this affects the on-top energy. This study provides a foundation for designing on-top density functionals and automatizing the active space choice in MC-PDFT.

  2. Motivational activation: a unifying hypothesis of orexin/hypocretin function.

    Science.gov (United States)

    Mahler, Stephen V; Moorman, David E; Smith, Rachel J; James, Morgan H; Aston-Jones, Gary

    2014-10-01

    Orexins (hypocretins) are two peptides (orexin A and B) produced from the pre-pro-orexin precursor and expressed in a limited region of dorsolateral hypothalamus. Orexins were originally thought to specifically mediate feeding and promote wakefulness, but it is now clear that they participate in a wide range of behavioral and physiological processes under select circumstances. Orexins primarily mediate behavior under situations of high motivational relevance, such as during physiological need states, exposure to threats or reward opportunities. We hypothesize that many behavioral functions of orexins (including regulation of sleep/wake cycling) reflect a fundamentally integrated function for orexins in translating motivational activation into organized suites of psychological and physiological processes supporting adaptive behaviors. We also discuss how numerous forms of neural heterogeneity modulate this function, allowing orexin neurons to organize diverse, adaptive responses in a variety of motivationally relevant situations. Thus, the involvement of orexins in diverse behaviors may reflect a common underlying function for this peptide system.

  3. Motivational activation: a unifying hypothesis of orexin/hypocretin function

    Science.gov (United States)

    Mahler, Stephen V; Moorman, David E; Smith, Rachel J; James, Morgan H; Aston-Jones, Gary

    2015-01-01

    Orexins (hypocretins) are two peptides (orexin A and B) produced from the pre-pro-orexin precursor and expressed in a limited region of dorsolateral hypothalamus. Orexins were originally thought to specifically mediate feeding and promote wakefulness, but it is now clear that they participate in a wide range of behavioral and physiological processes under select circumstances. Orexins primarily mediate behavior under situations of high motivational relevance, such as during physiological need states, exposure to threats or reward opportunities. We hypothesize that many behavioral functions of orexins (including regulation of sleep/wake cycling) reflect a fundamentally integrated function for orexins in translating motivational activation into organized suites of psychological and physiological processes supporting adaptive behaviors. We also discuss how numerous forms of neural heterogeneity modulate this function, allowing orexin neurons to organize diverse, adaptive responses in a variety of motivationally relevant situations. Thus, the involvement of orexins in diverse behaviors may reflect a common underlying function for this peptide system. PMID:25254979

  4. Activated and deactivated functional brain areas in the Deqi state: A functional MRI study.

    Science.gov (United States)

    Huang, Yong; Zeng, Tongjun; Zhang, Guifeng; Li, Ganlong; Lu, Na; Lai, Xinsheng; Lu, Yangjia; Chen, Jiarong

    2012-10-25

    We compared the activities of functional regions of the brain in the Deqi versus non-Deqi state, as reported by physicians and subjects during acupuncture. Twelve healthy volunteers received sham and true needling at the Waiguan (TE5) acupoint. Real-time cerebral functional MRI showed that compared with non-sensation after sham needling, true needling activated Brodmann areas 3, 6, 8, 9, 10, 11, 13, 20, 21, 37, 39, 40, 43, and 47, the head of the caudate nucleus, the parahippocampal gyrus, thalamus and red nucleus. True needling also deactivated Brodmann areas 1, 2, 3, 4, 5, 6, 7, 9, 10, 18, 24, 31, 40 and 46.

  5. Physically active academic lessons : Effects on physical fitness and executive functions in primary school children

    NARCIS (Netherlands)

    de Greeff, Johannes Wilhelmus

    2016-01-01

    There is increasing evidence that physical activity can improve cognitive functions of primary school children, especially the executive functions (functions that are important for goal directed cognition and behavior). Physically active academic lessons, however, do not improve executive functions

  6. Brain activation studies with PET and functional MRI

    Energy Technology Data Exchange (ETDEWEB)

    Yonekura, Yoshiharu [Fukui Medical Univ., Matsuoka (Japan). Biomedical Imaging Research Center; Sadato, Norihiro [Okazaki National Research Inst., Aichi (Japan). National Inst. for Physiological Sciences

    2002-01-01

    Application of PET and functional MRI in brain activation studies is reviewed. 3D-PET images obtained repeatedly after intravenous injection of about 370 MBq of H{sub 2}{sup 15}O can detect a faint blood flow change in the brain. Functional MRI can also detect the blood flow change in the brain due to blood oxygen level-dependent effect. Echo-planar imaging is popular in MRI with 1.5 or 3 T. Images are analyzed by statistical parametric mapping with correction of cerebral regions, anatomical normalization and statistics. PET data give the blood flow change by the H{sub 2}{sup 15}O incorporation into the brain and MRI data, by the scarce tissue oxygen consumption despite the change. Actual images during the cognition task-performance and of frequent artifacts are given. PET is suitable for studies of brain functions like sensibility and emotion and functional MRI, like cortex functions and clinical practices in identification of functional regions prior to surgery and evaluation of functional recovery of damaged brain. (K.H.)

  7. Function and biotechnology of extremophilic enzymes in low water activity

    Science.gov (United States)

    2012-01-01

    Enzymes from extremophilic microorganisms usually catalyze chemical reactions in non-standard conditions. Such conditions promote aggregation, precipitation, and denaturation, reducing the activity of most non-extremophilic enzymes, frequently due to the absence of sufficient hydration. Some extremophilic enzymes maintain a tight hydration shell and remain active in solution even when liquid water is limiting, e.g. in the presence of high ionic concentrations, or at cold temperature when water is close to the freezing point. Extremophilic enzymes are able to compete for hydration via alterations especially to their surface through greater surface charges and increased molecular motion. These properties have enabled some extremophilic enzymes to function in the presence of non-aqueous organic solvents, with potential for design of useful catalysts. In this review, we summarize the current state of knowledge of extremophilic enzymes functioning in high salinity and cold temperatures, focusing on their strategy for function at low water activity. We discuss how the understanding of extremophilic enzyme function is leading to the design of a new generation of enzyme catalysts and their applications to biotechnology. PMID:22480329

  8. XIAP reverses various functional activities of FRNK in endothelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Ahn, Sunyoung; Kim, Hyun Jeong [Department of Molecular Biology and Institute of Nanosensor and Biotechnology, BK21 Graduate Program for RNA Biology, Dankook Univiersity, 126, Jukjeon-dong, Suji-gu, Yongin-si, Gyeonggi-do 448-701 (Korea, Republic of); Chi, Sung-Gil [School of Life Sciences and Biotechnology, Korea University, Seoul 136-701 (Korea, Republic of); Park, Heonyong, E-mail: heonyong@dankook.ac.kr [Department of Molecular Biology and Institute of Nanosensor and Biotechnology, BK21 Graduate Program for RNA Biology, Dankook Univiersity, 126, Jukjeon-dong, Suji-gu, Yongin-si, Gyeonggi-do 448-701 (Korea, Republic of)

    2012-03-09

    Highlights: Black-Right-Pointing-Pointer FRNK domain is recruited into focal adhesion (FA), controlling endothelial cell adhesion. Black-Right-Pointing-Pointer XIAP binds the FRNK domain of FAK. Black-Right-Pointing-Pointer XIAP inhibits recruitment of FRNK into Fas and FRNK-promoted cell adhesion. Black-Right-Pointing-Pointer XIAP plays a key role in vascular functions of FRNK or FRNK domain-mediated vascular functions of FAK. -- Abstract: In endothelial cells, focal adhesion kinase (FAK) regulates cell proliferation, migration, adhesion, and shear-stimulated activation of MAPK. We recently found that FAK is recruited into focal adhesion (FA) sites through interactions with XIAP (X-chromosome linked inhibitor of apoptosis protein) and activated by Src kinase in response to shear stress. In this study, we examined which domain(s) of FAK is(are) important for various vascular functions such as FA recruiting, XIAP-binding and shear stress-stimulated ERK activation. Through a series of experiments, we determined that the FRNK domain is recruited into FA sites and promotes endothelial cell adhesion. Interestingly, XIAP knockdown was shown to reduce FA recruitment of FRNK and the cell adhesive effect of FRNK. In addition, we found that XIAP interacts with FRNK, suggesting cross-talk between XIAP and FRNK. We also demonstrated that FRNK inhibits endothelial cell migration and shear-stimulated ERK activation. These inhibitory effects of FRNK were reversed by XIAP knockdown. Taken together, we can conclude that XIAP plays a key role in vascular functions of FRNK or FRNK domain-mediated vascular functions of FAK.

  9. Brain activation in high-functioning older adults and falls

    Science.gov (United States)

    Wang, Cuiling; Ayers, Emmeline; Izzetoglu, Meltem; Holtzer, Roee

    2017-01-01

    Objective: To determine whether brain activity over the prefrontal cortex measured in real time during walking predicts falls in high-functioning older adults. Method: We examined166 older persons (mean age 75 years, 51% women) enrolled in a prospective aging study. High-functioning status defined as the absence of dementia or disability with normal gait diagnosed by study clinicians. The magnitude of task-related changes in oxygenated hemoglobin levels over the prefrontal cortex was measured with functional near-infrared spectroscopy during motor (walking at normal pace) and cognitive (reciting alternate letters of the alphabet) single tasks and a dual-task condition (walking while reciting alternate letters of the alphabet). Incident falls were prospectively assessed over a 50-month study period. Results: Over a mean follow-up of 33.9 ± 11.9 months, 116 falls occurred. Higher levels of prefrontal cortical activation during the dual-task walking condition predicted falls (hazard ratio adjusted for age, sex, education, medical illnesses and general mental status 1.32, 95% confidence interval 1.03–1.70). Neither behavioral outcomes (velocity or letter rate) on the dual task nor brain activation patterns on the single tasks (normal walk or talk alone) predicted falls in this high-functioning sample. The results remained robust after accounting for multiple confounders and for cognitive status, slow gait, previous falls, and frailty. Conclusions: Prefrontal brain activity levels while performing a cognitively demanding walking condition predicted falls in high-functioning seniors. These findings implicate neurobiological processes early in the pathogenesis of falls. PMID:27927937

  10. Functionally Selective AT(1) Receptor Activation Reduces Ischemia Reperfusion Injury

    DEFF Research Database (Denmark)

    Hostrup, Anders; Christensen, Gitte Lund; Bentzen, Bo Hjort

    2012-01-01

    of the physiological functions of AngII. The AT(1)R mediates its effects through both G protein-dependent and independent signaling, which can be separated by functionally selective agonists. In the present study we investigate the effect of AngII and the ß-arrestin biased agonist [SII]AngII on ischemia......]AngII had a protective effect. Together these results demonstrate a cardioprotective effect of simultaneous blockade of G protein signaling and activation of G protein independent signaling through AT(1 )receptors....

  11. Functional magnetic resonance imaging in the activation of working memory

    International Nuclear Information System (INIS)

    Spitzer, M.; Kammer, T.; Bellemann, M.E.; Gueckel, F.; Georgi, M.; Gass, A.; Brix, G.

    1996-01-01

    Functional magnetic resonance imaging was used in conjunction with a letter detection task for the study of working memory in 16 normal subjects. Because of movement artifacts, data from only 9 subjects were analysed. In the activation taks, subjects responded by pressing a button whenever any presented letter was the same as the second last in the sequence. In the control condition, the subjects had to respond to a fixed letter. Hence, the activation condition and the control condition differend only subjectively, i.e., regarding the task demand, whereas the stimuli and the type and frequency of response were identical. The activation condition produced significant activation in the dorsolateral prefrontal cortex (Brodmann's areas 10, 46, and 9). In contrast to experimental tasks previsouly used rather extensively to study the prefrontal cortex, the present paradigm is characterized by its simplicity, interpretability, and its ties to known neurophysiology of the frontal cortex. (orig.) [de

  12. Review: Production and functionality of active peptides from milk.

    Science.gov (United States)

    Muro Urista, C; Álvarez Fernández, R; Riera Rodriguez, F; Arana Cuenca, A; Téllez Jurado, A

    2011-08-01

    In recent years, research on the production of active peptides obtained from milk and their potential functionality has grown, to a great extent. Bioactive peptides have been defined as specific protein fragments that have a positive impact on body functions or conditions, and they may ultimately have an influence on health. Individual proteins of casein or milk-derived products such as cheese and yogurt have been used as a protein source to study the isolation and activity of peptides with several applications. Currently, the milk whey waste obtained in the production of cheese also represents a protein source from which active peptides could be isolated with potential industrial applications. The active properties of milk peptides and the results found with regard to their physiological effects have led to the classification of peptides as belonging to the group of ingredients of protein nature, appropriate for use in functional foods or pharmaceutical formulations. In this study, the main peptides obtained from milk protein and the past research studies about its production and biological activities will be explained. Second, an analysis will be made on the methods to determinate the biological activities, the separation of bioactive peptides and its structure identification. All of these form the base required to obtain synthetic peptides. Finally, we explain the experimental animal and human trials done in the past years. Nevertheless, more research is required on the design and implementation of equipment for the industrial production and separation of peptides. In addition, different authors suggest that more emphasis should therefore be given to preclinical studies, proving that results are consistent and that effects are demonstrated repeatedly by several research human groups.

  13. Sensorimotor peripheral nerve function and physical activity in older men

    DEFF Research Database (Denmark)

    Lange-Maia, B. S.; Cauley, J A; Newman, Anne B

    2016-01-01

    We determined whether sensorimotor peripheral nerve (PN) function was associated with physical activity (PA) in older men. The Osteoporotic Fractures in Men Study Pittsburgh, PA, site (n = 328, age 78.8 ± 4.7 years) conducted PN testing, including: peroneal motor and sural sensory nerve conduction...... (latencies, amplitudes: CMAP and SNAP for motor and sensory amplitude, respectively), 1.4g/10g monoflament (dorsum of the great toe), and neuropathy symptoms. ANOVA and multivariate linear regression modeled PN associations with PA (Physical Activity Scale for the Elderly [PASE] and SenseWear Armband). After...

  14. ACTIVITY-BASED COST ALLOCATION AND FUNCTION ANALYZES IN TRADE

    Directory of Open Access Journals (Sweden)

    TÜNDE VERES

    2011-01-01

    Full Text Available In this paper the author is thinking about the efficiency analyzes of trading. The most important evaluation factors of trade are the sales value, volume and the margin. Of course the easiest and fastest way is to follow the market situation by the turnover but for long term thinking the sales companies need to concentrate also for efficiency. Trading activity has some functions which can deeply effect for the final result and this is the reason to calculate their clear and reliable costs is an important condition of the decision making. The author reviews the cost categories and the basic functions in trading activity to find possible ways getting reliable information.

  15. Toxoplasma gondii actively inhibits neuronal function in chronically infected mice.

    Directory of Open Access Journals (Sweden)

    Fahad Haroon

    Full Text Available Upon infection with the obligate intracellular parasite Toxoplasma gondii, fast replicating tachyzoites infect a broad spectrum of host cells including neurons. Under the pressure of the immune response, tachyzoites convert into slow-replicating bradyzoites, which persist as cysts in neurons. Currently, it is unclear whether T. gondii alters the functional activity of neurons, which may contribute to altered behaviour of T. gondii-infected mice and men. In the present study we demonstrate that upon oral infection with T. gondii cysts, chronically infected BALB/c mice lost over time their natural fear against cat urine which was paralleled by the persistence of the parasite in brain regions affecting behaviour and odor perception. Detailed immunohistochemistry showed that in infected neurons not only parasitic cysts but also the host cell cytoplasm and some axons stained positive for Toxoplasma antigen suggesting that parasitic proteins might directly interfere with neuronal function. In fact, in vitro live cell calcium (Ca(2+ imaging studies revealed that tachyzoites actively manipulated Ca(2+ signalling upon glutamate stimulation leading either to hyper- or hypo-responsive neurons. Experiments with the endoplasmatic reticulum Ca(2+ uptake inhibitor thapsigargin indicate that tachyzoites deplete Ca(2+ stores in the endoplasmatic reticulum. Furthermore in vivo studies revealed that the activity-dependent uptake of the potassium analogue thallium was reduced in cyst harbouring neurons indicating their functional impairment. The percentage of non-functional neurons increased over time In conclusion, both bradyzoites and tachyzoites functionally silence infected neurons, which may significantly contribute to the altered behaviour of the host.

  16. Comparative studies of brain activation with MEG and functional MRI

    International Nuclear Information System (INIS)

    George, J.S.; Aine, C.J.; Sanders, J.A.; Lewine, J.D.; Caprihan, A.

    1993-01-01

    The past two years have witnessed the emergence of MRI as a functional imaging methodology. Initial demonstrations involved the injection of a paramagnetic contrast agent and required ultrafast echo planar imaging capability to adequately resolve the passage of the injected bolus. By measuring the local reduction in image intensity due to magnetic susceptibility, it was possible to calculate blood volume, which changes as a function of neural activation. Later developments have exploited endogenous contrast mechanisms to monitor changes in blood volume or in venous blood oxygen content. Recently, we and others have demonstrated that it is possible to make such measurements in a clinical imager, suggesting that the large installed base of such machines might be utilized for functional imaging. Although it is likely that functional MRI (fMRI) will subsume some of the clinical and basic neuroscience applications now touted for MEG, it is also clear that these techniques offer different largely complementary, capabilities. At the very least, it is useful to compare and cross-validate the activation maps produced by these techniques. Such studies will be valuable as a check on results of neuromagnetic distributed current reconstructions and will allow better characterization of the relationship between neurophysiological activation and associated hemodynamic changes. A more exciting prospect is the development of analyses that combine information from the two modalities to produce a better description of underlying neural activity than is possible with either technique in isolation. In this paper we describe some results from initial comparative studies and outline several techniques that can be used to treat MEG and fMRI data within a unified computational framework

  17. The integration of functional brain activity from adolescence to adulthood.

    Science.gov (United States)

    Kundu, Prantik; Benson, Brenda E; Rosen, Dana; Frangou, Sophia; Leibenluft, Ellen; Luh, Wen-Ming; Bandettini, Peter A; Pine, Daniel S; Ernst, Monique

    2018-02-27

    Age-related changes in human functional neuroanatomy are poorly understood. This is partly due to the limits to interpretation of standard fMRI. These limits relate to age-related variation in noise levels across subjects, and the frequent need for standard adult parcellations in developmental studies. Here we used an emerging MRI approach called multi-echo (ME)-fMRI to characterize functional brain changes with age. ME-fMRI acquires blood oxygenation level dependent (BOLD) signals while also quantifying T2* signal decay. This newly enables reliable analysis of BOLD components at the subject level. We hypothesized that BOLD components of the resting state are not stable with age, and would decrease in number from adolescence to adulthood. This runs counter to the current assumptions in neurodevelopmental analyses of brain connectivity that the number of components is a random effect. From resting state ME-fMRI of 51 healthy subjects of both sexes, between ages of 8.3 and 46.2 y, we found a highly significant (R=-0.55, p[dlt]0.001) exponential decrease in the number of BOLD components with age. The number of BOLD components were halved from adolescence to the fifth decade of life, stabilizing in middle adulthood. The regions driving this change were dorsolateral prefrontal cortices, parietal cortex, and cerebellum. The functional network of these regions centered on the cerebellum. We conclude that age-related decrease in BOLD component number concurs with the hypothesis of neurodevelopmental integration of functional brain activity. We show evidence that the cerebellum may play a key role in this process. SIGNIFICANCE STATEMENT Human brain development is ongoing to at least age 30. Functional MRI (fMRI) is key for studying the change in brain function with development. However, developmental fMRI studies have relied on reference maps of brain organization derived from adult data. This may limit sensitivity to major differences in younger brains. We created an f

  18. Functional MRI study of cerebral cortical activation during volitional swallowing

    International Nuclear Information System (INIS)

    Wakasa, Toru; Aiga, Hideki; Yanagi, Yoshinobu; Kawai, Noriko; Sugimoto, Tomosada; Kuboki, Takuo; Kishi, Kanji

    2002-01-01

    The purpose of this study was to investigate the somatotropic distribution and lateralization of motor and sensory cortical activity during swallowing in healthy adult human subjects using functional MR imaging. Nine healthy right-handed adult volunteers (6 men, 3 women; ages 22-38) were examined. Their cortical activities were evoked by having them swallow, five times, a small bolus of water (3 ml) supplied through a plastic catheter. As a positive control, the subjects performed five repetitions of right-handed grasping tasks. Blood oxygenation level-dependent images were obtained using a 1.5 Tesla MR system (Magnetom Vision, Siemens Germany; repetition time/echo time (TR/TE)=0.96/0.66, flip angle (FA)=90 deg). T1 weighted anatomical images were obtained for the same slices in each subject. Cerebral activity was observed most notably in the primary motor cortex and primary somatosensory cortex, followed by the premotor cortex, anterior cingulate cortex, frontal operculum, and insula. The hand-grasping task activated relatively superior parts of the primary motor and somatosensory cortices. The swallowing task, on the other hand, activated the inferior parts of the pre- and postcentral gyri. The hand-grasping activation of motor and sensory cortices was localized absolutely on the contralateral side, whereas swallowing activated the motor cortex either bilaterally or unilaterally. Swallowing activated the sensory cortex almost always bilaterally. This study suggested that fMRI could be used to identify the specific areas of cortical activation caused by various tasks, and to differentiate the locations of cortical activation between tasks. (author)

  19. Functional MRI study of cerebral cortical activation during volitional swallowing

    Energy Technology Data Exchange (ETDEWEB)

    Wakasa, Toru; Aiga, Hideki; Yanagi, Yoshinobu; Kawai, Noriko; Sugimoto, Tomosada; Kuboki, Takuo; Kishi, Kanji [Okayama Univ. (Japan). Graduate School of Medicine and Dentistry

    2002-12-01

    The purpose of this study was to investigate the somatotropic distribution and lateralization of motor and sensory cortical activity during swallowing in healthy adult human subjects using functional MR imaging. Nine healthy right-handed adult volunteers (6 men, 3 women; ages 22-38) were examined. Their cortical activities were evoked by having them swallow, five times, a small bolus of water (3 ml) supplied through a plastic catheter. As a positive control, the subjects performed five repetitions of right-handed grasping tasks. Blood oxygenation level-dependent images were obtained using a 1.5 Tesla MR system (Magnetom Vision, Siemens Germany; repetition time/echo time (TR/TE)=0.96/0.66, flip angle (FA)=90 deg). T1 weighted anatomical images were obtained for the same slices in each subject. Cerebral activity was observed most notably in the primary motor cortex and primary somatosensory cortex, followed by the premotor cortex, anterior cingulate cortex, frontal operculum, and insula. The hand-grasping task activated relatively superior parts of the primary motor and somatosensory cortices. The swallowing task, on the other hand, activated the inferior parts of the pre- and postcentral gyri. The hand-grasping activation of motor and sensory cortices was localized absolutely on the contralateral side, whereas swallowing activated the motor cortex either bilaterally or unilaterally. Swallowing activated the sensory cortex almost always bilaterally. This study suggested that fMRI could be used to identify the specific areas of cortical activation caused by various tasks, and to differentiate the locations of cortical activation between tasks. (author)

  20. Glucose metabolism regulates T cell activation, differentiation and functions

    Directory of Open Access Journals (Sweden)

    Clovis Steve Palmer

    2015-01-01

    Full Text Available The adaptive immune system is equipped to eliminate both tumors and pathogenic microorganisms. It requires a series of complex and coordinated signals to drive the activation, proliferation and differentiation of appropriate T cell subsets. It is now established that changes in cellular activation are coupled to profound changes in cellular metabolism. In addition, emerging evidence now suggest that specific metabolic alterations associated with distinct T cell subsets may be ancillary to their differentiation and influential in their immune functions. The Warburg effect originally used to describe a phenomenon in which most cancer cells relied on aerobic glycolysis for their growth is a key process that sustain T cell activation and differentiation. Here we review how different aspects of metabolism in T cells influence their functions, focusing on the emerging role of key regulators of glucose metabolism such as HIF-1α. A thorough understanding of the role of metabolism in T cell function could provide insights into mechanisms involved in inflammatory-mediated conditions, with the potential for developing novel therapeutic approaches to treat these diseases.

  1. THE ACTIVITY IMPACT ON COLLECTIVE FUNCTIONAL CAPACITY IN ELDERLY

    Directory of Open Access Journals (Sweden)

    Matheus Bitencourt da Cruz de Jesus

    2017-07-01

    Full Text Available The Brazilian population has introduced changes in its demographic pattern, presenting a new scenario with an increased in rates of chronic diseases and functional limitations. Objective: To evaluate the impact of collective activities in regard to the functional capacity of elderly practitioners and not practitioners of those. Method: It is a descriptive transversal study by means of a sociodemographic questionnaire adapted from the FIM scale (Functional Independency Measure, which compared functional performance among the elderly of a cohabitation group at a private university (G1 with a group of similar elderly people belonging to a long-stay institution (G2. The comparison between the MIF scale proportions and the other variables was under analyzed with Pearson χ2 and Fisher’s exact at a significance level of 5% as well as with the Spearman’s correlation coefficient calculation. For the data analysis, Stata 12 software was utilized, and the tables were built by Excel for Windows 2013. Result: Based on the 40 elderly individuals who were part of the study, 70% of them were female The majority G1 (100% and G2 (40%,between the ages of 60 and 69 years old, low levels of education, no partner, and low number of children. The average between the FIM scale and the groups present a difference of plus 12.45 for the G1. In the Spearman correlation, it was observed that the control of sphincters obtained a strong correlation (0.845, and all correlations presented 5% statistic difference. Conclusion: Thus, when comparing the MIF total of the two groups, the group G1 functional independence obtained superior to G2. These findings underscore the importance of collective activities to improve the functional capacity of the elderly.

  2. Extracellular enzyme activity assay as indicator of soil microbial functional diversity and activity

    DEFF Research Database (Denmark)

    Hendriksen, Niels Bohse; Winding, Anne

    2012-01-01

    Extracellular enzyme activity assay as indicator of soil microbial functional diversity and activity Niels Bohse Hendriksen, Anne Winding. Department of Environmental Science, Aarhus University, 4000 Roskilde, Denmark Soils provide numerous essential ecosystem services such as carbon cycling...... awareness of the threats to soil and the ecosystem services has fostered the need for a thorough understanding of soil functions and activities. Soils are very species-rich and show great functional heterogeneity. While molecular analysis of gene expression is developing, simple and inexpensive indicators......, recycling of nutrients and waste, soil remediation, plant growth support and regulation of above ground biodiversity, resilience, and soil suppressiveness. As such, soil ecosystem services are beneficial and vital for human life and at the same time threatened by anthropogenic activities. Increasing...

  3. Jungle Honey Enhances Immune Function and Antitumor Activity

    Science.gov (United States)

    Fukuda, Miki; Kobayashi, Kengo; Hirono, Yuriko; Miyagawa, Mayuko; Ishida, Takahiro; Ejiogu, Emenike C.; Sawai, Masaharu; Pinkerton, Kent E.; Takeuchi, Minoru

    2011-01-01

    Jungle honey (JH) is collected from timber and blossom by wild honey bees that live in the tropical forest of Nigeria. JH is used as a traditional medicine for colds, skin inflammation and burn wounds as well as general health care. However, the effects of JH on immune functions are not clearly known. Therefore, we investigated the effects of JH on immune functions and antitumor activity in mice. Female C57BL/6 mice were injected with JH (1 mg/mouse/day, seven times intra-peritoneal). After seven injections, peritoneal cells (PC) were obtained. Antitumor activity was assessed by growth of Lewis Lung Carcinoma/2 (LL/2) cells. PC numbers were increased in JH-injected mice compared to control mice. In Dot Plot analysis by FACS, a new cell population appeared in JH-injected mice. The percent of Gr-1 surface antigen and the intensity of Gr-1 antigen expression of PC were increased in JH-injected mice. The new cell population was neutrophils. JH possessed chemotactic activity for neutrophils. Tumor incidence and weight were decreased in JH-injected mice. The ratio of reactive oxygen species (ROS) producing cells was increased in JH-injected mice. The effective component in JH was fractionized by gel filtration using HPLC and had an approximate molecular weight (MW) of 261. These results suggest that neutrophils induced by JH possess potent antitumor activity mediated by ROS and the effective immune component of JH is substrate of MW 261. PMID:19141489

  4. Jungle Honey Enhances Immune Function and Antitumor Activity

    Directory of Open Access Journals (Sweden)

    Miki Fukuda

    2011-01-01

    Full Text Available Jungle honey (JH is collected from timber and blossom by wild honey bees that live in the tropical forest of Nigeria. JH is used as a traditional medicine for colds, skin inflammation and burn wounds as well as general health care. However, the effects of JH on immune functions are not clearly known. Therefore, we investigated the effects of JH on immune functions and antitumor activity in mice. Female C57BL/6 mice were injected with JH (1 mg/mouse/day, seven times intra-peritoneal. After seven injections, peritoneal cells (PC were obtained. Antitumor activity was assessed by growth of Lewis Lung Carcinoma/2 (LL/2 cells. PC numbers were increased in JH-injected mice compared to control mice. In Dot Plot analysis by FACS, a new cell population appeared in JH-injected mice. The percent of Gr-1 surface antigen and the intensity of Gr-1 antigen expression of PC were increased in JH-injected mice. The new cell population was neutrophils. JH possessed chemotactic activity for neutrophils. Tumor incidence and weight were decreased in JH-injected mice. The ratio of reactive oxygen species (ROS producing cells was increased in JH-injected mice. The effective component in JH was fractionized by gel filtration using HPLC and had an approximate molecular weight (MW of 261. These results suggest that neutrophils induced by JH possess potent antitumor activity mediated by ROS and the effective immune component of JH is substrate of MW 261.

  5. Functional imaging of sympathetic activation during mental stress.

    Science.gov (United States)

    Fechir, M; Gamer, M; Blasius, I; Bauermann, T; Breimhorst, M; Schlindwein, P; Schlereth, T; Birklein, F

    2010-04-01

    Activation of the sympathetic nervous system (SNS) is essential in adapting to environmental stressors and in maintaining homeostasis. This reaction can also turn into maladaptation, associated with a wide spectrum of stress-related diseases. Up to now, the cortical mechanisms of sympathetic activation in acute mental stress have not been sufficiently characterized. We therefore investigated cerebral activation applying functional magnetic resonance imaging (fMRI) during performance of a mental stress task with graded levels of difficulty, i.e. four versions of a Stroop task (Colour Word Interference Test, CWT) in healthy subjects. To analyze stress-associated sympathetic activation, skin conductance and heart rate were continuously recorded. The results show that sympathetic activation through mental stress is associated with distinct cerebral regions being immediately involved in task performance (visual, motor, and premotor areas). Other activated regions (right insula, dorsolateral superior frontal gyrus, cerebellar regions) are unrelated to task performance. These latter regions have previously been considered to be involved in mediating different stress responses. The results might furthermore serve as a basis for future investigations of the connection between these cortical regions in the generation of stress-related diseases. Copyright 2009 Elsevier Inc. All rights reserved.

  6. Enhancement of carrier mobility in pentacene thin-film transistor on SiO 2 by controlling the initial film growth modes

    Science.gov (United States)

    Qi, Qiong; Yu, Aifang; Jiang, Peng; Jiang, Chao

    2009-02-01

    Pentacene thin-film transistors (TFTs) were fabricated on thermally grown SiO 2 gate insulator under the conditions of various pre-cleaning treatments. Initial nucleation and growth of the material films on treated substrates were observed by atomic force microscope. The performance of fabricated TFT devices with different surface cleaning approaches was found to be highly related to the initial film morphologies. In contrast to the three-dimensional island-like growth mode on SiO 2 under an organic cleaning process, a layer-by-layer initial growth occurred on the SiO 2 insulator cleaned with ammonia solution, which was believed to be the origination of the excellent electrical properties of the TFT device. Field effect mobility of the TFT device could achieve as high as 1.0 cm 2/Vs on the bared SiO 2/Si substrate and the on/off ratio was over 10 6.

  7. Application of tosylate-doped poly(3,4ethylenedioxythiophene) (PEDOT) films into bottom contact pentacene organic thin film transistors (OTFTs)

    International Nuclear Information System (INIS)

    Ali, M.A.; Kim, H.H.; Jeong, K.H.; Soh, H.S.; Nam, H.S.; Lee, J.G.; Lee, E.G.

    2010-01-01

    The effect of iron(III) p-toluenesulfonate hexahydrate (Fe(PTS) 3 ) concentration on the formation and patternability of poly(3,4ethylenedioxythiophene) (PEDOT) films on (3-aminopropyl)trimethoxysilane (APS) monolayer was investigated. Low deposition rate yielded highly conductive and very smooth PEDOT films. However, the spin-coated oxidants in low Fe(PTS) 3 concentrations were susceptible to moistures, leading to the poorly patterned PEDOT films. Increasing Fe(PTS) 3 concentration enabled the fine patterning of the films. The fabricated thin film transistors with PEDOT electrodes formed on 30 wt.% Fe(PTS) 3 revealed the saturation mobility of 0.16 cm 2 /V s and subthreshold slope of 0.5 V/decade. The obtained low contact resistance was 12 kΩ cm, possibly due to the negligible interface morphological discontinuity at the pentacene-PEDOT interface.

  8. Ginger extract inhibits LPS induced macrophage activation and function

    Directory of Open Access Journals (Sweden)

    Bruch David

    2008-01-01

    Full Text Available Abstract Background Macrophages play a dual role in host defence. They act as the first line of defence by mounting an inflammatory response to antigen exposure and also act as antigen presenting cells and initiate the adaptive immune response. They are also the primary infiltrating cells at the site of inflammation. Inhibition of macrophage activation is one of the possible approaches towards modulating inflammation. Both conventional and alternative approaches are being studied in this regard. Ginger, an herbal product with broad anti inflammatory actions, is used as an alternative medicine in a number of inflammatory conditions like rheumatic disorders. In the present study we examined the effect of ginger extract on macrophage activation in the presence of LPS stimulation. Methods Murine peritoneal macrophages were stimulated by LPS in presence or absence of ginger extract and production of proinflammatory cytokines and chemokines were observed. We also studied the effect of ginger extract on the LPS induced expression of MHC II, B7.1, B7.2 and CD40 molecules. We also studied the antigen presenting function of ginger extract treated macrophages by primary mixed lymphocyte reaction. Results We observed that ginger extract inhibited IL-12, TNF-α, IL-1β (pro inflammatory cytokines and RANTES, MCP-1 (pro inflammatory chemokines production in LPS stimulated macrophages. Ginger extract also down regulated the expression of B7.1, B7.2 and MHC class II molecules. In addition ginger extract negatively affected the antigen presenting function of macrophages and we observed a significant reduction in T cell proliferation in response to allostimulation, when ginger extract treated macrophages were used as APCs. A significant decrease in IFN-γ and IL-2 production by T cells in response to allostimulation was also observed. Conclusion In conclusion ginger extract inhibits macrophage activation and APC function and indirectly inhibits T cell activation.

  9. Functional brain activation associated with working memory training and transfer.

    Science.gov (United States)

    Clark, Cameron M; Lawlor-Savage, Linette; Goghari, Vina M

    2017-09-15

    While behavioural trials of working memory (WM) training have received much attention in recent years, a lesser explored parallel approach is functional neuroimaging. A small literature has suggested a complex time course for functional activation pattern changes following WM training (i.e. not simply increasing or decreasing due to training); however, no study to date has examined such neuroplastic effects in both the training task (dual n-back) and the fluid intelligence transfer task to which the training is purported to transfer (Raven's Matrices). This study investigated neural correlates of WM training in healthy young adults randomized to six weeks of WM training, or an active control condition (processing speed training) with a pre- and post-training fMRI design. Results indicated significant reductions in activation for the WM trained group in key WM-task related areas for trained WM tasks after training compared to the processing speed active control group. The same pattern of training related decreases in activation for the WM trained group was not observed for the transfer task, which is consistent with null results for all cognitive outcomes of the present trial. The observed pattern of results suggests that repetitive practice with a complex task does indeed lead to neuroplastic processes that very likely represent the reduced demand for attentional control while sub-components of the task become more routinized with practice. We suggest that future research investigate neural correlates of WM training in populations for which WM itself is impaired and/or behavioural trials of WM training have returned more promising results. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Biological function of activation-induced cytidine deaminase (AID

    Directory of Open Access Journals (Sweden)

    Ritu Kumar

    2014-10-01

    Full Text Available Activation-induced Cytidine Deaminase (AID is an essential regulator of B cell diversification, but its full range of action has until recently been an enigma. Based on homology, it was originally proposed to be an RNA-editing enzyme, but so far, no RNA substrates are known. Rather, it functions by deaminating cytidine, and in this manner, coupled with base-excision repair or mismatch repair machinery, it is a natural mutator. This allows it to play a central role in adaptive immunity, whereby it initiates the processes of class switch recombination and somatic hypermutation to help generate a diverse and high-affinity repertoire of immunoglobulin isotypes. More recently, it has been appreciated that methylated cytidine, already known as a key epigenetic mark on DNA controlling gene expression, can also be a target for AID modification. Coupled with repair machinery, this can facilitate the active removal of methylated DNA. This activity can impact the process of cellular reprogramming, including transition of a somatic cell to pluripotency, which requires major reshuffling of epigenetic memory. Thus, seemingly disparate roles for AID in controlling immune diversity and epigenetic memory have a common mechanistic basis. However, the very activity that is so useful for B cell diversity and cellular reprogramming is dangerous for the integrity of the genome. Thus, AID expression and activity is tightly regulated, and deregulation is associated with diseases including cancer. Here, we review the range of AID functions with a focus on its mechanisms of action and regulation. Major questions remain to be answered concerning how and when AID is targeted to specific loci and how this impacts development and disease.

  11. Functional imaging reveals movement preparatory activity in the vegetative state

    Directory of Open Access Journals (Sweden)

    Tristan A Bekinschtein

    2011-01-01

    Full Text Available The Vegetative State (VS is characterized by the absence of awareness of self or the environment and preserved autonomic functions. The diagnosis relies critically on the lack of consistent signs of purposeful behavior in response to external stimulation. Yet, given that patients with disorders of consciousness often exhibit fragmented movement patterns, voluntary actions may go unnoticed. Here we designed a simple motor paradigm that could potentially detect residual conscious awareness in VS patients with mild to severe brain damage by examining the neural correlates of motor preparation in response to verbal commands. Twenty-four patients who met the diagnostic criteria for VS were recruited for this study. Eleven of these patients showing preserved auditory evoked potentials underwent functional magnetic resonance imaging (fMRI to test for basic speech processing. Five of these patients, who showed word related activity, were included in a second fMRI study aimed at detecting functional changes in premotor cortex elicited by specific verbal instructions to move either their left or their right hand. Despite the lack of overt muscle activity, two patients out of five activated the dorsal premotor cortex contralateral to the instructed hand, consistent with movement preparation. Given that movement preparation in response to a motor command is a sign of purposeful behavior, our results are consistent with residual conscious awareness in these patients. We believe that the identification of positive results with fMRI using this simple task, may complement the clinical assessment by helping attain a more precise diagnosis in patients with disorders of consciousness.

  12. Functional analysis of Ficolin-3 mediated complement activation

    DEFF Research Database (Denmark)

    Hein, Estrid; Honoré, Christian; Skjoedt, Mikkel-Ole

    2010-01-01

    assessed by C4, C3 and terminal complement complex (TCC) deposition. Serum Ficolin-3 bound to acBSA in a calcium dependent manner, while only minimal binding of Ficolin-2 and no binding of Ficolin-1 were observed. No binding to normal BSA was seen for any of the Ficolins. Serum C4, C3 and TCC deposition...... was applied to the samples that inhibited interference from the classical pathway due to the presence of anti-BSA antibodies in some sera. We describe a novel functional method for measuring complement activation mediated by Ficolin-3 in human serum up to the formation of TCC. The assay provides...

  13. The adipogenic acetyltransferase Tip60 targets activation function 1 of peroxisome proliferator-activated receptor gamma

    DEFF Research Database (Denmark)

    van Beekum, Olivier; Brenkman, Arjan B; Grøntved, Lars

    2008-01-01

    The transcription factor peroxisome proliferator-activated receptor gamma (PPARgamma) plays a key role in the regulation of lipid and glucose metabolism in adipocytes, by regulating their differentiation, maintenance, and function. The transcriptional activity of PPARgamma is dictated by the set...... in cells, and through use of chimeric proteins, we established that coactivation by Tip60 critically depends on the N-terminal activation function 1 of PPARgamma, a domain involved in isotype-specific gene expression and adipogenesis. Chromatin immunoprecipitation experiments showed that the endogenous Tip...... of proteins with which this nuclear receptor interacts under specific conditions. Here we identify the HIV-1 Tat-interacting protein 60 (Tip60) as a novel positive regulator of PPARgamma transcriptional activity. Using tandem mass spectrometry, we found that PPARgamma and the acetyltransferase Tip60 interact...

  14. Biological activity of lactoferrin-functionalized biomimetic hydroxyapatite nanocrystals.

    Science.gov (United States)

    Nocerino, Nunzia; Fulgione, Andrea; Iannaccone, Marco; Tomasetta, Laura; Ianniello, Flora; Martora, Francesca; Lelli, Marco; Roveri, Norberto; Capuano, Federico; Capparelli, Rosanna

    2014-01-01

    The emergence of bacterial strains resistant to antibiotics is a general public health problem. Progress in developing new molecules with antimicrobial properties has been made. In this study, we evaluated the biological activity of a hybrid nanocomposite composed of synthetic biomimetic hydroxyapatite surface-functionalized by lactoferrin (LF-HA). We evaluated the antimicrobial, anti-inflammatory, and antioxidant properties of LF-HA and found that the composite was active against both Gram-positive and Gram-negative bacteria, and that it modulated proinflammatory and anti-inflammatory responses and enhanced antioxidant properties as compared with LF alone. These results indicate the possibility of using LF-HA as an antimicrobial system and biomimetic hydroxyapatite as a candidate for innovative biomedical applications.

  15. Electrocatalytic Activity and Selectivity - a Density Functional Theory Study

    DEFF Research Database (Denmark)

    Karamad, Mohammadreza

    The focus of the current PhD thesis is to design new electro-catalysts, by changing the morphology and composition of the catalysts, to tune the electro-catalytic performance. We use Density Functional Theory (DFT) calculations, to examine activity, selectivity and stability of the designed electro...... by the location of Cu atoms into different layers of Pt(111). While the presence of Cu into the surface layer strengthens the interaction between surface and adsorbates, the presence of Cu atoms into the subsurface layer has the opposite effect. These findings can be used to design new electro...... reduction of CO2 at the cathode side: 1) high overpotential that hinders this reaction from being an energy efficient process, and 2) low selectivity towards desired reaction products. We have taken two approaches to improve the selectivity and activity in the reduction of CO2. Firstly, we create...

  16. Active membrane having uniform physico-chemically functionalized ion channels

    Science.gov (United States)

    Gerald, II, Rex E; Ruscic, Katarina J; Sears, Devin N; Smith, Luis J; Klingler, Robert J; Rathke, Jerome W

    2012-09-24

    The present invention relates to a physicochemically-active porous membrane for electrochemical cells that purports dual functions: an electronic insulator (separator) and a unidirectional ion-transporter (electrolyte). The electrochemical cell membrane is activated for the transport of ions by contiguous ion coordination sites on the interior two-dimensional surfaces of the trans-membrane unidirectional pores. One dimension of the pore surface has a macroscopic length (1 nm-1000 .mu.m) and is directed parallel to the direction of an electric field, which is produced between the cathode and the anode electrodes of an electrochemical cell. The membrane material is designed to have physicochemical interaction with ions. Control of the extent of the interactions between the ions and the interior pore walls of the membrane and other materials, chemicals, or structures contained within the pores provides adjustability of the ionic conductivity of the membrane.

  17. Endothelial RIG-I activation impairs endothelial function

    International Nuclear Information System (INIS)

    Asdonk, Tobias; Motz, Inga; Werner, Nikos; Coch, Christoph; Barchet, Winfried; Hartmann, Gunther; Nickenig, Georg; Zimmer, Sebastian

    2012-01-01

    Highlights: ► RIG-I activation impairs endothelial function in vivo. ► RIG-I activation alters HCAEC biology in vitro. ► EPC function is affected by RIG-I stimulation in vitro. -- Abstract: Background: Endothelial dysfunction is a crucial part of the chronic inflammatory atherosclerotic process and is mediated by innate and acquired immune mechanisms. Recent studies suggest that pattern recognition receptors (PRR) specialized in immunorecognition of nucleic acids may play an important role in endothelial biology in a proatherogenic manner. Here, we analyzed the impact of endothelial retinoic acid inducible gene I (RIG-I) activation upon vascular endothelial biology. Methods and results: Wild type mice were injected intravenously with 32.5 μg of the RIG-ligand 3pRNA (RNA with triphosphate at the 5′end) or polyA control every other day for 7 days. In 3pRNA-treated mice, endothelium-depended vasodilation was significantly impaired, vascular oxidative stress significantly increased and circulating endothelial microparticle (EMP) numbers significantly elevated compared to controls. To gain further insight in RIG-I dependent endothelial biology, cultured human coronary endothelial cells (HCAEC) and endothelial progenitor cells (EPC) were stimulated in vitro with 3pRNA. Both cells types express RIG-I and react with receptor upregulation upon stimulation. Reactive oxygen species (ROS) formation is enhanced in both cell types, whereas apoptosis and proliferation is not significantly affected in HCAEC. Importantly, HCAEC release significant amounts of proinflammatory cytokines in response to RIG-I stimulation. Conclusion: This study shows that activation of the cytoplasmatic nucleic acid receptor RIG-I leads to endothelial dysfunction. RIG-I induced endothelial damage could therefore be an important pathway in atherogenesis.

  18. Endothelial RIG-I activation impairs endothelial function

    Energy Technology Data Exchange (ETDEWEB)

    Asdonk, Tobias, E-mail: tobias.asdonk@ukb.uni-bonn.de [Department of Medicine/Cardiology, University of Bonn, Sigmund-Freud-Str. 25, 53105 Bonn (Germany); Motz, Inga; Werner, Nikos [Department of Medicine/Cardiology, University of Bonn, Sigmund-Freud-Str. 25, 53105 Bonn (Germany); Coch, Christoph; Barchet, Winfried; Hartmann, Gunther [Institute for Clinical Chemistry and Clinical Pharmacology, University of Bonn, Sigmund-Freud-Str. 25, 53105 Bonn (Germany); Nickenig, Georg; Zimmer, Sebastian [Department of Medicine/Cardiology, University of Bonn, Sigmund-Freud-Str. 25, 53105 Bonn (Germany)

    2012-03-30

    Highlights: Black-Right-Pointing-Pointer RIG-I activation impairs endothelial function in vivo. Black-Right-Pointing-Pointer RIG-I activation alters HCAEC biology in vitro. Black-Right-Pointing-Pointer EPC function is affected by RIG-I stimulation in vitro. -- Abstract: Background: Endothelial dysfunction is a crucial part of the chronic inflammatory atherosclerotic process and is mediated by innate and acquired immune mechanisms. Recent studies suggest that pattern recognition receptors (PRR) specialized in immunorecognition of nucleic acids may play an important role in endothelial biology in a proatherogenic manner. Here, we analyzed the impact of endothelial retinoic acid inducible gene I (RIG-I) activation upon vascular endothelial biology. Methods and results: Wild type mice were injected intravenously with 32.5 {mu}g of the RIG-ligand 3pRNA (RNA with triphosphate at the 5 Prime end) or polyA control every other day for 7 days. In 3pRNA-treated mice, endothelium-depended vasodilation was significantly impaired, vascular oxidative stress significantly increased and circulating endothelial microparticle (EMP) numbers significantly elevated compared to controls. To gain further insight in RIG-I dependent endothelial biology, cultured human coronary endothelial cells (HCAEC) and endothelial progenitor cells (EPC) were stimulated in vitro with 3pRNA. Both cells types express RIG-I and react with receptor upregulation upon stimulation. Reactive oxygen species (ROS) formation is enhanced in both cell types, whereas apoptosis and proliferation is not significantly affected in HCAEC. Importantly, HCAEC release significant amounts of proinflammatory cytokines in response to RIG-I stimulation. Conclusion: This study shows that activation of the cytoplasmatic nucleic acid receptor RIG-I leads to endothelial dysfunction. RIG-I induced endothelial damage could therefore be an important pathway in atherogenesis.

  19. Active robotic training improves locomotor function in a stroke survivor

    Directory of Open Access Journals (Sweden)

    Krishnan Chandramouli

    2012-08-01

    Full Text Available Abstract Background Clinical outcomes after robotic training are often not superior to conventional therapy. One key factor responsible for this is the use of control strategies that provide substantial guidance. This strategy not only leads to a reduction in volitional physical effort, but also interferes with motor relearning. Methods We tested the feasibility of a novel training approach (active robotic training using a powered gait orthosis (Lokomat in mitigating post-stroke gait impairments of a 52-year-old male stroke survivor. This gait training paradigm combined patient-cooperative robot-aided walking with a target-tracking task. The training lasted for 4-weeks (12 visits, 3 × per week. The subject’s neuromotor performance and recovery were evaluated using biomechanical, neuromuscular and clinical measures recorded at various time-points (pre-training, post-training, and 6-weeks after training. Results Active robotic training resulted in considerable increase in target-tracking accuracy and reduction in the kinematic variability of ankle trajectory during robot-aided treadmill walking. These improvements also transferred to overground walking as characterized by larger propulsive forces and more symmetric ground reaction forces (GRFs. Training also resulted in improvements in muscle coordination, which resembled patterns observed in healthy controls. These changes were accompanied by a reduction in motor cortical excitability (MCE of the vastus medialis, medial hamstrings, and gluteus medius muscles during treadmill walking. Importantly, active robotic training resulted in substantial improvements in several standard clinical and functional parameters. These improvements persisted during the follow-up evaluation at 6 weeks. Conclusions The results indicate that active robotic training appears to be a promising way of facilitating gait and physical function in moderately impaired stroke survivors.

  20. Objectively Measured Physical Activity and Cognitive Function in Older Adults

    Science.gov (United States)

    Zhu, Wenfei; Wadley, Virginia G.; Howard, Virginia J.; Hutto, Brent; Blair, Steven N.; Hooker, Steven P.

    2016-01-01

    Purpose Emerging evidence suggests physical activity (PA) is associated with cognitive function. To overcome limitations of self-report PA measures, this study investigated the association of accelerometer-measured PA with incident cognitive impairment and longitudinal cognition among older adults. Methods Participants were recruited from the cohort study, REasons for Geographic and Racial Differences in Stroke (REGARDS), in U.S.. Accelerometers provided PA measures, including percent of total accelerometer wearing time spent in moderate-to-vigorous intensity PA (MVPA%), light-intensity PA and sedentary time, for 4-7 consecutive days at baseline. Cognitive impairment was defined by Six-Item Screener. Letter fluency, animal fluency, word list learning and Montreal Cognitive Assessment (orientation and recall) were conducted to assess executive function and memory. Results Participants (N=6,452, 69.7 ± 8.5 yr, 55.3% women, 30.5% black) with usable accelerometer and cognition measures spent extremely limited time in MVPA (1.5% ± 1.9% of accelerometer wearing time). During an average of 3 years of follow-up, 346 cases of incident cognitive impairment were observed. After adjustments, participants in higher MVPA% quartiles had a lower risk of cognitive impairment (i.e. Quartile 2: OR=0.64, 95% CI: 0.48-0.84), and better maintenance in executive function (≥0.03 z-score units) and memory (≥0.12 z-score units), compared with Quartile 1 (P<0.05). Stratified analyses showed the same association among white adults, but higher MVPA% was associated with better maintenance of only memory among black adults. No significance was found for light-intensity PA or sedentary time. Conclusion There was a dose-response relationship between MVPA% and cognitive function in older adults, with higher levels associated with a 36% lower risk of cognitive impairment and better maintenance of memory and executive function over time, particularly in white adults. PMID:27580146

  1. Organizers and activators: Cytosolic Nox proteins impacting on vascular function.

    Science.gov (United States)

    Schröder, Katrin; Weissmann, Norbert; Brandes, Ralf P

    2017-08-01

    NADPH oxidases of the Nox family are important enzymatic sources of reactive oxygen species (ROS) in the cardiovascular system. Of the 7 members of the Nox family, at least three depend for their activation on specific cytosolic proteins. These are p47phox and its homologue NoxO1 and p67phox and its homologue NoxA1. Also the Rho-GTPase Rac is important but as this protein has many additional functions, it will not be covered here. The Nox1 enzyme is preferentially activated by the combination of NoxO1 with NoxA1, whereas Nox2 gains highest activity with p47phox together with p67phox. As p47phox, different to NoxO1 contains an auto inhibitory region it has to be phosphorylated prior to complex formation. In the cardio-vascular system, all cytosolic Nox proteins are expressed but the evidence for their contribution to ROS production is not well established. Most data have been collected for p47phox, whereas NoxA1 has basically not yet been studied. In this article the specific aspects of cytosolic Nox proteins in the cardiovascular system with respect to Nox activation, their expression and their importance will be reviewed. Finally, it will be discussed whether cytosolic Nox proteins are suitable pharmacological targets to tamper with vascular ROS production. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  2. Physical activity, functional ability, and disease activity in children and adolescents with juvenile idiopathic arthritis.

    Science.gov (United States)

    Gueddari, S; Amine, B; Rostom, S; Badri, D; Mawani, N; Ezzahri, M; Moussa, F; Shyen, S; Abouqal, R; Chkirat, B; Hajjaj-Hassouni, N

    2014-09-01

    Juvenile idiopathic arthritis (JIA) is a chronic condition known to cause pain-related complications in youth and affect children's physical functioning. There is no data in Arabic children with JIA about the impact of illness upon their physical activity. The objective of this study was to explore physical activity (PA) in children and adolescents with JIA compared with a healthy population and to examine associations between PA, functional ability, and disease activity. Our study included patients with JIA and group control aged between 8 and 17 years. The diagnosis was used according to the International League of Association of Rheumatology (ILAR) criteria 2001. Sociodemographic data and clinical features were collected. Physical activity level and energy expenditure were assessed with a 1-day activity diary and the metabolic equivalent (MET), respectively. Functional ability was assessed with the Moroccan version of the Childhood Health Assessment Questionnaire (CHAQ). Disease activity was measured using the Juvenile Arthritis Disease Activity Score (JADAS). Fifty patients and 50 controls were included (mean ± SD age 11.5 ± 3.3 and 10.5 ± 3.8 years, respectively; p = 0.49) with masculine predominance n = 30 (59.6 %) and n = 29 (58 %), respectively (p = 0.26). The median disease duration was 4.3 years (2-5). The median analog scale (VAS) pain was 20 (10-40). Fourteen patients (28 %) had an active disease. Patient population consisted in majority of oligoarticular arthritis (28 %), 14 patients. The mean of energy expenditure and physical activity were significantly higher in the JIA group. The JIA group spent more time in bed and less time on moderate to vigorous PA than the control group. There is no significant relationship between PA, functional ability, and disease activity. Our study suggests that children and adolescents with JIA have low PA levels and are at risk of losing the benefits of PA. Low PA is not related to

  3. Functional neuroimaging of conversion disorder: the role of ancillary activation.

    Science.gov (United States)

    Burke, Matthew J; Ghaffar, Omar; Staines, W Richard; Downar, Jonathan; Feinstein, Anthony

    2014-01-01

    Previous functional neuroimaging studies investigating the neuroanatomy of conversion disorder have yielded inconsistent results that may be attributed to small sample sizes and disparate methodologies. The objective of this study was to better define the functional neuroanatomical correlates of conversion disorder. Ten subjects meeting clinical criteria for unilateral sensory conversion disorder underwent fMRI during which a vibrotactile stimulus was applied to anesthetic and sensate areas. A block design was used with 4 s of stimulation followed by 26 s of rest, the pattern repeated 10 times. Event-related group averages of the BOLD response were compared between conditions. All subjects were right-handed females, with a mean age of 41. Group analyses revealed 10 areas that had significantly greater activation (p conversion symptoms are associated with a pattern of abnormal cerebral activation comprising neural networks implicated in emotional processing and sensory integration. Further study of the roles and potential interplay of these networks may provide a basis for an underlying psychobiological mechanism of conversion disorder.

  4. Active chemisorption sites in functionalized ionic liquids for carbon capture.

    Science.gov (United States)

    Cui, Guokai; Wang, Jianji; Zhang, Suojiang

    2016-07-25

    Development of novel technologies for the efficient and reversible capture of CO2 is highly desired. In the last decade, CO2 capture using ionic liquids has attracted intensive attention from both academia and industry, and has been recognized as a very promising technology. Recently, a new approach has been developed for highly efficient capture of CO2 by site-containing ionic liquids through chemical interaction. This perspective review focuses on the recent advances in the chemical absorption of CO2 using site-containing ionic liquids, such as amino-based ionic liquids, azolate ionic liquids, phenolate ionic liquids, dual-functionalized ionic liquids, pyridine-containing ionic liquids and so on. Other site-containing liquid absorbents such as amine-based solutions, switchable solvents, and functionalized ionic liquid-amine blends are also investigated. Strategies have been discussed for how to activate the existent reactive sites and develop novel reactive sites by physical and chemical methods to enhance CO2 absorption capacity and reduce absorption enthalpy. The carbon capture mechanisms of these site-containing liquid absorbents are also presented. Particular attention has been paid to the latest progress in CO2 capture in multiple-site interactions by amino-free anion-functionalized ionic liquids. In the last section, future directions and prospects for carbon capture by site-containing ionic liquids are outlined.

  5. Extracellular Enzyme Activity assay as indicator of soil microbial functional diversity and activity

    DEFF Research Database (Denmark)

    Hendriksen, Niels Bohse; Winding, Anne

    2012-01-01

    and soil ecosystem services. The soil enzyme activity has been measured by the use of fluorogenic model substrates e.g. methylumbelliferyl (MUF) substrates for a number of enzymes involved in the degradation of polysaccharides as cellulose, hemicellulose and chitin, while degradation of proteins has been......Extracellular Enzyme Activity assay as indicator of soil microbial functional diversity and activity Niels Bohse Hendriksen, Anne Winding. Department of Environmental Science, Aarhus University, 4000 Roskilde, Denmark Soil enzymes originate from a variety of organisms, notably fungi and bacteria......, experimental conditions of extraction of enzymes from soils, buffer and pH, substrate concentration, temperature and the necessary controls were optimized and standardized. This has resulted in an optimized standard operating procedure of EEA, which are being tested as an indicator of soil functional diversity...

  6. Microglia actively regulate the number of functional synapses.

    Directory of Open Access Journals (Sweden)

    Kyungmin Ji

    Full Text Available Microglia are the immunocompetent cells of the central nervous system. In the physiological setting, their highly motile processes continually survey the local brain parenchyma and transiently contact synaptic elements. Although recent work has shown that the interaction of microglia with synapses contributes to synaptic remodeling during development, the role of microglia in synaptic physiology is just starting to get explored. To assess this question, we employed an electrophysiological approach using two methods to manipulate microglia in culture: organotypic hippocampal brain slices in which microglia were depleted using clodronate liposomes, and cultured hippocampal neurons to which microglia were added. We show here that the frequency of excitatory postsynaptic current increases in microglia-depleted brain slices, consistent with a higher synaptic density, and that this enhancement ensures from the loss of microglia since it is reversed when the microglia are replenished. Conversely, the addition of microglia to neuronal cultures decreases synaptic activity and reduces the density of synapses, spine numbers, surface expression of AMPA receptor (GluA1, and levels of synaptic adhesion molecules. Taken together, our findings demonstrate that non-activated microglia acutely modulate synaptic activity by regulating the number of functional synapses in the central nervous system.

  7. Biological activity of lactoferrin-functionalized biomimetic hydroxyapatite nanocrystals

    Directory of Open Access Journals (Sweden)

    Nocerino N

    2014-03-01

    Full Text Available Nunzia Nocerino,1 Andrea Fulgione,1 Marco Iannaccone,1 Laura Tomasetta,1 Flora Ianniello,1 Francesca Martora,1 Marco Lelli,2 Norberto Roveri,2 Federico Capuano,3 Rosanna Capparelli1 1Department of Agriculture Special Biotechnology Center Federico II, CeBIOTEC Biotechnology, University of Naples Federico II, Naples, 2Department of Chemistry, G Ciamician, Alma Mater Studiorum, University of Bologna, Bologna, 3Department of Food Inspection IZS ME, Naples, Italy Abstract: The emergence of bacterial strains resistant to antibiotics is a general public health problem. Progress in developing new molecules with antimicrobial properties has been made. In this study, we evaluated the biological activity of a hybrid nanocomposite composed of synthetic biomimetic hydroxyapatite surface-functionalized by lactoferrin (LF-HA. We evaluated the antimicrobial, anti-inflammatory, and antioxidant properties of LF-HA and found that the composite was active against both Gram-positive and Gram-negative bacteria, and that it modulated proinflammatory and anti-inflammatory responses and enhanced antioxidant properties as compared with LF alone. These results indicate the possibility of using LF-HA as an antimicrobial system and biomimetic hydroxyapatite as a candidate for innovative biomedical applications. Keywords: lactoferrin, hydroxyapatite nanocrystals, biomimetism, biological activity, drug delivery

  8. Interaction between functional health literacy, patient activation, and glycemic control

    Directory of Open Access Journals (Sweden)

    Woodard LD

    2014-07-01

    Full Text Available LeChauncy D Woodard, Cassie R Landrum, Amber B Amspoker, David Ramsey, Aanand D Naik Veterans Affairs Health Services Research and Development Center for Innovations in Quality, Effectiveness and Safety, Michael E DeBakey Veterans Affairs Medical Center, and Section of Health Services Research, Department of Medicine, Baylor College of Medicine, Houston, TX, USA Background: Functional health literacy (FHL and patient activation can impact diabetes control through enhanced diabetes self-management. Less is known about the combined effect of these characteristics on diabetes outcomes. Using brief, validated measures, we examined the interaction between FHL and patient activation in predicting glycosylated hemoglobin (HbA1c control among a cohort of multimorbid diabetic patients.Methods: We administered a survey via mail to 387 diabetic patients with coexisting ­hypertension and ischemic heart disease who received outpatient care at one regional VA medical center between November 2010 and December 2010. We identified patients with the study conditions using the International Classification of Diseases-Ninth Revision-Clinical ­Modification (ICD-9-CM diagnoses codes and Current Procedure Terminology (CPT ­procedures codes. Surveys were returned by 195 (50.4% patients. We determined patient activation levels based on participant responses to the 13-item Patient Activation Measure and FHL levels using the single-item screening question, “How confident are you filling out medical forms by yourself?” We reviewed patient medical records to assess glycemic control. We used multiple logistic regression to examine whether activation and FHL were individually or jointly related to HbA1c control.Results: Neither patient activation nor FHL was independently related to glycemic control in the unadjusted main effects model; however, the interaction between the two was significantly associated with glycemic control (odds ratio 1.05 [95% confidence

  9. Functional structure of spontaneous sleep slow oscillation activity in humans.

    Directory of Open Access Journals (Sweden)

    Danilo Menicucci

    Full Text Available BACKGROUND: During non-rapid eye movement (NREM sleep synchronous neural oscillations between neural silence (down state and neural activity (up state occur. Sleep Slow Oscillations (SSOs events are their EEG correlates. Each event has an origin site and propagates sweeping the scalp. While recent findings suggest a SSO key role in memory consolidation processes, the structure and the propagation of individual SSO events, as well as their modulation by sleep stages and cortical areas have not been well characterized so far. METHODOLOGY/PRINCIPAL FINDINGS: We detected SSO events in EEG recordings and we defined and measured a set of features corresponding to both wave shapes and event propagations. We found that a typical SSO shape has a transition to down state, which is steeper than the following transition from down to up state. We show that during SWS SSOs are larger and more locally synchronized, but less likely to propagate across the cortex, compared to NREM stage 2. Also, the detection number of SSOs as well as their amplitudes and slopes, are greatest in the frontal regions. Although derived from a small sample, this characterization provides a preliminary reference about SSO activity in healthy subjects for 32-channel sleep recordings. CONCLUSIONS/SIGNIFICANCE: This work gives a quantitative picture of spontaneous SSO activity during NREM sleep: we unveil how SSO features are modulated by sleep stage, site of origin and detection location of the waves. Our measures on SSOs shape indicate that, as in animal models, onsets of silent states are more synchronized than those of neural firing. The differences between sleep stages could be related to the reduction of arousal system activity and to the breakdown of functional connectivity. The frontal SSO prevalence could be related to a greater homeostatic need of the heteromodal association cortices.

  10. Function of the activated protein C (APC) autolysis loop in activated FVIII inactivation.

    Science.gov (United States)

    Cramer, Thomas J; Gale, Andrew J

    2011-06-01

    Activated protein C (APC) binds to its substrates activated factor V (FVa) and activated factor VIII (FVIIIa) with a basic exosite that consists of loops 37, 60, 70 and the autolysis loop. These loops have a high density of basic residues, resulting in a positive charge on the surface of APC. Many of these residues are important in the interaction of APC with FVa and FVIIIa. The current study focused on the function of the autolysis loop in the interaction with FVIIIa. This loop was previously shown to interact with FVa, and it inhibits APC inactivation by plasma serpins. Charged residues of the autolysis loop were individually mutated to alanine and the activity of these mutants was assessed in functional FVIIIa inactivation assays. The autolysis loop was functionally important for FVIIIa inactivation. Mutation of R306, K311 and R314 each resulted in significantly reduced FVIIIa inactivation. The inactivating cleavages of FVIIIa at R336 and R562 were affected equally by the mutations. Protein S and FV stimulated cleavage at R562 more than cleavage at R336, independent of mutations in the autolysis loop. Together, these results confirmed that the autolysis loop plays a significant role as part of the basic exosite on APC in the interaction with FVIIIa. © 2011 Blackwell Publishing Ltd.

  11. Functional metabolomics reveals novel active products in the DHA metabolome

    Directory of Open Access Journals (Sweden)

    Masakazu eShinohara

    2012-04-01

    Full Text Available Endogenous mechanisms for successful resolution of an acute inflammatory response and the local return to homeostasis are of interest because excessive inflammation underlies many human diseases. In this review, we provide an update and overview of functional metabolomics that identified a new bioactive metabolome of docosahexaenoic acid (DHA. Systematic studies revealed that DHA was converted to DHEA-derived novel bioactive products as well as aspirin-triggered (AT forms of protectins. The new oxygenated DHEA derived products blocked PMN chemotaxis, reduced P-selectin expression and platelet-leukocyte adhesion, and showed organ protection in ischemia/reperfusion injury. These products activated cannabinoid receptor (CB2 receptor and not CB1 receptors. The AT-PD1 reduced neutrophil (PMN recruitment in murine peritonitis. With human cells, AT-PD1 decreased transendothelial PMN migration as well as enhanced efferocytosis of apoptotic human PMN by macrophages. The recent findings reviewed here indicate that DHEA oxidative metabolism and aspirin-triggered conversion of DHA produce potent novel molecules with anti-inflammatory and organ-protective properties, opening the DHA metabolome functional roles.

  12. Impact of functional properties and release kinetics on antioxidant activity of biopolymer active films and coatings.

    Science.gov (United States)

    Benbettaïeb, Nasreddine; Tanner, Cadhla; Cayot, Philippe; Karbowiak, Thomas; Debeaufort, Frédéric

    2018-03-01

    This work deals with the study of the release kinetics of some natural antioxidants (ferulic acid, caffeic acid and tyrosol) from chitosan-fish gelatin edible films immersed ethanol at 96%, as well as the kinetics of their antioxidant activity using the DPPH assay. The aim was to determine how film functional properties influence the release kinetic and antioxidant activity. The addition of antioxidants to chitosan-fish gelatin matrix decreased the water vapour permeability by more than 30%. The tensile strength (TS) increased up to 50% after the incorporation of antioxidants. Some molecular interactions between polymer chains and antioxidants were confirmed by FTIR where spectra displayed a shift of the amide-III peak. Films containing caffeic acid or a caffeic-ferulic acid mixture exhibited the highest radical scavenging activity, leading to a 90% antioxidant activity at equilibrium but the release rate controlled the efficacy of the system. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Fitness, Fatness, Physical Activity, and Autonomic Function in Midlife.

    Science.gov (United States)

    Kiviniemi, Antti M; Perkiömäki, Nelli; Auvinen, Juha; Niemelä, Maisa; Tammelin, Tuija; Puukka, Katri; Ruokonen, Aimo; Keinänen-Kiukaanniemi, Sirkka; Tulppo, Mikko P; Järvelin, Marjo-Riitta; Jämsä, Timo; Huikuri, Heikki V; Korpelainen, Raija

    2017-12-01

    Although low cardiorespiratory fitness (CRF), physical inactivity, and obesity are associated with impaired autonomic function, they are also extensively interrelated. The present study aimed to assess the extent to which they contribute to autonomic function independently of each other. At the age of 46 yr, 1383 men and 1761 women without cardiorespiratory diseases and diabetes underwent assessments of vagally mediated heart rate (HR) variability (root mean square of successive differences in R-R interval (rMMSD)), peak HR during a submaximal step test (CRF), and 60-s HR recovery (HRR). Moderate-to-vigorous physical activity (MVPA; ≥3.5 METs, 2 wk) was measured by wrist-worn accelerometer and body fat percentage (Fat%) by bioimpedance. In men, CRF and Fat% were significantly associated with higher rMSSD (standardized β = 0.31 and -0.16) and HRR (β = 0.19 and -0.18), whereas higher MVPA was linked with higher HRR (β = 0.13) when including CRF, MVPA, and Fat% in the initial regression. After adjustments for other lifestyle and cardiometabolic factors, CRF remained significantly associated with rMMSD (β = 0.24) and HRR (β = 0.14), as did MVPA with HRR (β = 0.11). In women, CRF was associated with rMSSD (β = 0.23) and HRR (β = 0.15), and MVPA (β = 0.17) and Fat% (β = -0.07) with HRR, when CRF, MVPA, and Fat% were adjusted for each other. After further adjustments, CRF remained a significant determinant of rMSSD (β = 0.20) and HRR (β = 0.13), as did MVPA with HRR (β = 0.15). The final models explained 23% and 21% of variation in rMSSD and HRR in men, and 10% and 12% in women, respectively. CRF was a more important determinant of cardiac autonomic function than MVPA and body fat. Furthermore, MVPA but not body fat was independently associated with cardiac autonomic function in both men and women.

  14. Physical Activity and Cognitive Function of Long-Distance Walkers : Studying Four Days Marches Participants

    NARCIS (Netherlands)

    Wouters, Hans; Aalbers, Teun; Maessen, Martijn F. H.; Verbeek, Andre L. M.; Rikkert, Marcel G. M. Olde; Kessels, Roy P. C.; Hopman, Maria T. E.; Eijsvogels, Thijs M. H.

    2017-01-01

    Studies show physical activity to be beneficial for cognitive function. However, studies usually included individuals who were not particularly inclined to exercise. Following research among master athletes, we examined associations between physical activity and cognitive function in participants of

  15. Shoulder muscle activity and function in common shoulder rehabilitation exercises.

    Science.gov (United States)

    Escamilla, Rafael F; Yamashiro, Kyle; Paulos, Lonnie; Andrews, James R

    2009-01-01

    , posterior tilt and ER. The serratus anterior also helps stabilize the medial border and inferior angle of the scapular, preventing scapular IR (winging) and anterior tilt. If normal scapular movements are disrupted by abnormal scapular muscle firing patterns, weakness, fatigue, or injury, the shoulder complex functions less efficiency and injury risk increases. Scapula position and humeral rotation can affect injury risk during humeral elevation. Compared with scapular protraction, scapular retraction has been shown to both increase subacromial space width and enhance supraspinatus force production during humeral elevation. Moreover, scapular IR and scapular anterior tilt, both of which decrease subacromial space width and increase impingement risk, are greater when performing scaption with IR ('empty can') compared with scaption with ER ('full can'). There are several exercises in the literature that exhibit high to very high activity from the rotator cuff, deltoids and scapular muscles, such as prone horizontal abduction at 100 degrees abduction with ER, flexion and abduction with ER, 'full can' and 'empty can', D1 and D2 diagonal pattern flexion and extension, ER and IR at 0 degrees and 90 degrees abduction, standing extension from 90-0 degrees , a variety of weight-bearing upper extremity exercises, such as the push-up, standing scapular dynamic hug, forward scapular punch, and rowing type exercises. Supraspinatus activity is similar between 'empty can' and 'full can' exercises, although the 'full can' results in less risk of subacromial impingement. Infraspinatus and subscapularis activity have generally been reported to be higher in the 'full can' compared with the 'empty can', while posterior deltoid activity has been reported to be higher in the 'empty can' than the 'full can'.

  16. Functional Bowel Disorders Are Associated with a Central Immune Activation

    Directory of Open Access Journals (Sweden)

    Per G. Farup

    2017-01-01

    Full Text Available Background. Subjects with depression and unexplained neurological symptoms have a high prevalence of gastrointestinal comorbidity probably related to the brain-gut communication. This study explored associations between functional gastrointestinal disorders (FGID and inflammatory markers in subjects with these disorders. Methods. The FGID, including irritable bowel syndrome (IBS, were classified according to the Rome III criteria, and degree of symptoms was assessed with IBS symptom severity score (IBS-SSS. A range of interleukins (IL, chemokines and growth factors, tryptophan, and kynurenine were analysed in serum and the cerebrospinal fluid (CSF, and short-chain fatty acids (SCFA were analysed in the faeces. The results are reported as partial correlation (pc and p values. Results. Sixty-six subjects were included. IBS was associated with high levels of tryptophan (p=0.048 and kynurenine (p=0.019 and low level of IL-10 (p=0.047 in the CSF. IBS-SSS was associated with high tumor necrosis factor and low IL-10 in the CSF; pc=0.341 and p=0.009 and pc=−0.299 and p=0.023, respectively. Propionic minus butyric acid in faeces was negatively associated with IL-10 in the CSF (pc=−0.416, p=0.005. Conclusions. FGID were associated with a proinflammatory immune activation in the central nervous system and a disturbed tryptophan metabolism that could have been mediated by the faecal microbiota.

  17. Molecularly imprinted hydrogels as functional active packaging materials.

    Science.gov (United States)

    Benito-Peña, Elena; González-Vallejo, Victoria; Rico-Yuste, Alberto; Barbosa-Pereira, Letricia; Cruz, José Manuel; Bilbao, Ainhoa; Alvarez-Lorenzo, Carmen; Moreno-Bondi, María Cruz

    2016-01-01

    This paper describes the synthesis of novel molecularly imprinted hydrogels (MIHs) for the natural antioxidant ferulic acid (FA), and their application as packaging materials to prevent lipid oxidation of butter. A library of MIHs was synthesized using a synthetic surrogate of FA, 3-(4-hydroxy-3-methoxyphenyl)propionic acid (HFA), as template molecule, ethyleneglycol dimethacrylate (EDMA) as cross-linker, and 1-allylpiperazine (1-ALPP) or 2-(dimethylamino)ethyl methacrylate (DMAEMA), in combination with 2-hydroxyethyl methacrylate (HEMA) as functional monomers, at different molar concentrations. The DMAEMA/HEMA-based MIHs showed the greatest FA loading capacity, while the 1-ALLP/HEMA-based polymers exhibited the highest imprinting effect. During cold storage, FA-loaded MIHs protected butter from oxidation and led to TBARs values that were approximately half those of butter stored without protection and 25% less than those recorded for butter covered with hydrogels without FA, potentially extending the shelf life of butter. Active packaging is a new field of application for MIHs with great potential in the food industry. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Transcription elongation factor GreA has functional chaperone activity.

    Science.gov (United States)

    Li, Kun; Jiang, Tianyi; Yu, Bo; Wang, Limin; Gao, Chao; Ma, Cuiqing; Xu, Ping; Ma, Yanhe

    2012-01-01

    Bacterial GreA is an indispensable factor in the RNA polymerase elongation complex. It plays multiple roles in transcriptional elongation, and may be implicated in resistance to various stresses. In this study, we show that Escherichia coli GreA inhibits aggregation of several substrate proteins under heat shock condition. GreA can also effectively promote the refolding of denatured proteins. These facts reveal that GreA has chaperone activity. Distinct from many molecular chaperones, GreA does not form stable complexes with unfolded substrates. GreA overexpression confers the host cells with enhanced resistance to heat shock and oxidative stress. Moreover, GreA expression in the greA/greB double mutant could suppress the temperature-sensitive phenotype, and dramatically alleviate the in vivo protein aggregation. The results suggest that bacterial GreA may act as chaperone in vivo. These results suggest that GreA, in addition to its function as a transcription factor, is involved in protection of cellular proteins against aggregation.

  19. Investigating the function spiral in later life: Aging attitudes, physical activity, and gait.

    Science.gov (United States)

    Whitehead, Brenda R

    2017-06-01

    This study tests the Function Spiral Model, which proposes that functional decline often occurs prematurely: negative aging attitudes reduce activity engagement, which then advances functional decline via physical deconditioning. A total of 89 adults aged 61-96 ( M = 77) years completed a questionnaire assessing aging attitudes and physical activity and participated in a follow-up assessment of gait/balance and function. Results supported the process model: physical activity mediated the impact of negative aging attitudes on gait/balance, and gait/balance mediated the impact of physical activity on function. Findings highlight multiple points of intervention that could mitigate the acceleration of functional decline in later life.

  20. Enhancement of carrier mobility in pentacene thin-film transistor on SiO{sub 2} by controlling the initial film growth modes

    Energy Technology Data Exchange (ETDEWEB)

    Qi Qiong; Yu Aifang; Jiang Peng [National Center for Nanoscience and Technology, No.11, Beiyitiao Zhongguancun, Beijing 100190 (China); Jiang Chao, E-mail: jiangch@nanoctr.cn [National Center for Nanoscience and Technology, No.11, Beiyitiao Zhongguancun, Beijing 100190 (China)

    2009-02-15

    Pentacene thin-film transistors (TFTs) were fabricated on thermally grown SiO{sub 2} gate insulator under the conditions of various pre-cleaning treatments. Initial nucleation and growth of the material films on treated substrates were observed by atomic force microscope. The performance of fabricated TFT devices with different surface cleaning approaches was found to be highly related to the initial film morphologies. In contrast to the three-dimensional island-like growth mode on SiO{sub 2} under an organic cleaning process, a layer-by-layer initial growth occurred on the SiO{sub 2} insulator cleaned with ammonia solution, which was believed to be the origination of the excellent electrical properties of the TFT device. Field effect mobility of the TFT device could achieve as high as 1.0 cm{sup 2}/Vs on the bared SiO{sub 2}/Si substrate and the on/off ratio was over 10{sup 6}.

  1. The Contribution of Executive Functions to Participation in School Activities of Children with High Functioning Autism Spectrum Disorder

    Science.gov (United States)

    Zingerevich, Chaya; Patricia D., LaVesser

    2009-01-01

    This study describes the contribution of executive functions to participation in school activities of children diagnosed with ASD ages 6-9 years while controlling for sensory processing. Twenty-four children, ages 73-112 months (S.D. = 11.4), diagnosed with high functioning ASD were assessed with the Wisconsin Card Sorting Test. Their teachers…

  2. Building an Understanding of Functions: A Series of Activities for Pre-Calculus

    Science.gov (United States)

    Carducci, Olivia M.

    2008-01-01

    Building block toys can be used to illustrate various concepts connected with functions including graphs and rates of change of linear and exponential functions, piecewise functions, and composition of functions. Five brief activities suitable for a pre-calculus course are described.

  3. Executive Functions and Motor Ability Contribute to Children's Participation in Daily Activities

    Science.gov (United States)

    Rosenberg, Limor; Jacobi, Shani; Bart, Orit

    2017-01-01

    Executive functions are crucial for efficient daily functioning. However, the contribution of executive functions to the participation in daily life activities of children, have been inadequately studied. The study aimed to examine the unique contribution of executive functions, beyond motor ability, to the diversity and independence of children's…

  4. Ramiprilate inhibits functional matrix metalloproteinase activity in Crohn's disease fistulas

    DEFF Research Database (Denmark)

    Efsen, Eva; Saermark, Torben; Hansen, Alastair

    2011-01-01

    Increased expression of matrix metalloproteinase (MMP)-2, -3 and -9 has been demonstrated in Crohn's disease fistulas, but it is unknown whether these enzymes are biologically active and represent a therapeutic target. Therefore, we investigated the proteolytic activity of MMPs in fistula tissue...... and examined the effect of inhibitors, including clinically available drugs that beside their main action also suppress MMPs. Fistula specimens were obtained by surgical excision from 22 patients with Crohn's disease and from 10 patients with fistulas resulting from other causes. Colonic endoscopic biopsies......-diamine-tetraacetic acid (EDTA), the synthetic broad-spectrum inhibitor, GM6001, the angiotensin-converting enzyme (ACE) inhibitor, ramiprilate, and the tetracycline, doxycycline. In Crohn's disease fistulas, about 50% of the total protease activity was attributable to MMP activity. The average total MMP activity...

  5. Functional Synchronization: The Emergence of Coordinated Activity in Human Systems

    Directory of Open Access Journals (Sweden)

    Andrzej Nowak

    2017-06-01

    Full Text Available The topical landscape of psychology is highly compartmentalized, with distinct phenomena explained and investigated with recourse to theories and methods that have little in common. Our aim in this article is to identify a basic set of principles that underlie otherwise diverse aspects of human experience at all levels of psychological reality, from neural processes to group dynamics. The core idea is that neural, behavioral, mental, and social structures emerge through the synchronization of lower-level elements (e.g., neurons, muscle movements, thoughts and feelings, individuals into a functional unit—a coherent structure that functions to accomplish tasks. The coherence provided by the formation of functional units may be transient, persisting only as long as necessary to perform the task at hand. This creates the potential for the repeated assembly and disassembly of functional units in accordance with changing task demands. This perspective is rooted in principles of complexity science and non-linear dynamical systems and is supported by recent discoveries in neuroscience and recent models in cognitive and social psychology. We offer guidelines for investigating the emergence of functional units in different domains, thereby honoring the topical differentiation of psychology while providing an integrative foundation for the field.

  6. Physical activity and cognitive function of community Chinese elderly in Hong Kong (HK) and Guangzhou (GZ).

    Science.gov (United States)

    Su, Elena X F; Lin, Y Q; Zhang, S L; Leung, Grace T Y; Lam, Linda C W; Chiu, Helen F K

    2015-06-01

    Some studies demonstrated that physical activity may have beneficial effect on cognitive function. The objective of the study was to estimate the association between physical activity and cognitive function in community-dwelling elderly Chinese in Hong Kong (HK) and Guangzhou (GZ). In the neighborhood of HK and GZ, a convenience sample of 557 (260 in HK and 297 in GZ) older persons without dementia aged over 60 years (73.4 ± 6.5) was recruited. Physical activity was measured using a checklist. Information on physical activity participation, cognitive function, and other variables were collected. Multivariate linear regression analyses were performed to evaluate the association between physical activity and cognitive function. Total number of physical activities showed significant association with the delayed recall test (p 0.05) CONCLUSION: Physical activity may not be associated with better cognitive function among elderly Chinese independently of other factors.

  7. Physically active academic lessons: Effects on physical fitness and executive functions in primary school children

    OpenAIRE

    de Greeff, Johannes Wilhelmus

    2016-01-01

    There is increasing evidence that physical activity can improve cognitive functions of primary school children, especially the executive functions (functions that are important for goal directed cognition and behavior). Physically active academic lessons, however, do not improve executive functions in primary school children. This is the conclusion of the thesis of UMCG-researcher Marck de Greeff. A two-year teaching method (called ‘Fit & Vaardig op school’) was developed to improve executive...

  8. Recent Advances in Momordica charantia: Functional Components and Biological Activities.

    Science.gov (United States)

    Jia, Shuo; Shen, Mingyue; Zhang, Fan; Xie, Jianhua

    2017-11-28

    Momordica charantia L. ( M. charantia ), a member of the Cucurbitaceae family, is widely distributed in tropical and subtropical regions of the world. It has been used in folk medicine for the treatment of diabetes mellitus, and its fruit has been used as a vegetable for thousands of years. Phytochemicals including proteins, polysaccharides, flavonoids, triterpenes, saponins, ascorbic acid and steroids have been found in this plant. Various biological activities of M. charantia have been reported, such as antihyperglycemic, antibacterial, antiviral, antitumor, immunomodulation, antioxidant, antidiabetic, anthelmintic, antimutagenic, antiulcer, antilipolytic, antifertility, hepatoprotective, anticancer and anti-inflammatory activities. However, both in vitro and in vivo studies have also demonstrated that M. charantia may also exert toxic or adverse effects under different conditions. This review addresses the chemical constituents of M. charantia and discusses their pharmacological activities as well as their adverse effects, aimed at providing a comprehensive overview of the phytochemistry and biological activities of M. charantia .

  9. Recent Advances in Momordica charantia: Functional Components and Biological Activities

    Directory of Open Access Journals (Sweden)

    Shuo Jia

    2017-11-01

    Full Text Available Momordica charantia L. (M. charantia, a member of the Cucurbitaceae family, is widely distributed in tropical and subtropical regions of the world. It has been used in folk medicine for the treatment of diabetes mellitus, and its fruit has been used as a vegetable for thousands of years. Phytochemicals including proteins, polysaccharides, flavonoids, triterpenes, saponins, ascorbic acid and steroids have been found in this plant. Various biological activities of M. charantia have been reported, such as antihyperglycemic, antibacterial, antiviral, antitumor, immunomodulation, antioxidant, antidiabetic, anthelmintic, antimutagenic, antiulcer, antilipolytic, antifertility, hepatoprotective, anticancer and anti-inflammatory activities. However, both in vitro and in vivo studies have also demonstrated that M. charantia may also exert toxic or adverse effects under different conditions. This review addresses the chemical constituents of M. charantia and discusses their pharmacological activities as well as their adverse effects, aimed at providing a comprehensive overview of the phytochemistry and biological activities of M. charantia.

  10. Functional activity of the rats’ hepatocytes under cancerogenesis

    Directory of Open Access Journals (Sweden)

    V. V. Ivchuk

    2007-10-01

    Full Text Available Enzymatic activity in rat’s hepatocytes under carcinoma Geuren T8 development as well as after introduction of rhenium compounds and cis-platin were studied. It has been determined that the decrease of enzymatic activity contrary to the control animals has been observed under simultaneous injection of cis-platin and cluster rhenium compounds in a liposome form. That confirms possible hepatoprotective properties of the rhenium compounds.

  11. Consistency of a lumbar movement pattern across functional activities in people with low back pain.

    Science.gov (United States)

    Marich, Andrej V; Hwang, Ching-Ting; Salsich, Gretchen B; Lang, Catherine E; Van Dillen, Linda R

    2017-05-01

    Limitation in function is a primary reason people with low back pain seek medical treatment. Specific lumbar movement patterns, repeated throughout the day, have been proposed to contribute to the development and course of low back pain. Varying the demands of a functional activity test may provide some insight into whether people display consistent lumbar movement patterns during functional activities. Our purpose was to examine the consistency of the lumbar movement pattern during variations of a functional activity test in people with low back pain and back-healthy people. 16 back-healthy adults and 32 people with low back pain participated. Low back pain participants were classified based on the level of self-reported functional limitations. Participants performed 5 different conditions of a functional activity test. Lumbar excursion in the early phase of movement was examined. The association between functional limitations and early phase lumbar excursion for each test condition was examined. People with low back pain and high levels of functional limitation demonstrated a consistent pattern of greater early phase lumbar excursion across test conditions (plow back pain adopt consistent movement patterns during the performance of functional activities. Our findings indicate that the lumbar spine consistently moves more readily into its available range in people with low back pain and high levels of functional limitation. How the lumbar spine moves during a functional activity may contribute to functional limitations. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Antifouling activity of enzyme‐functionalized silica nanobeads

    Science.gov (United States)

    Zanoni, Michele; Habimana, Olivier; Amadio, Jessica

    2015-01-01

    ABSTRACT The amelioration of biofouling in industrial processing equipment is critical for performance and reliability. While conventional biocides are effective in biofouling control, they are potentially hazardous to the environment and in some cases corrosive to materials. Enzymatic approaches have been shown to be effective and can overcome the disadvantages of traditional biocides, however they are typically uneconomic for routine biofouling control. The aim of this study was to design a robust and reusable enzyme‐functionalized nano‐bead system having biofilm dispersion properties. This work describes the biochemical covalent functionalization of silica‐based nanobeads (hereafter referred to as Si‐NanoB) with Proteinase K (PK). Results showed that PK‐functionalized Si‐NanoB are effective in dispersing both protein‐based model biofilms and structurally altering Pseudomonas fluorescens biofilms, with significant decreases in surface coverage and thickness of 30.1% and 38.85%, respectively, while increasing surface roughness by 19 % following 24 h treatments on bacterial biofilms. This study shows that enzyme‐functionalized nanobeads may potentially be an environmentally friendly and cost effective alternative to pure enzyme and chemical treatments. Biotechnol. Bioeng. 2016;113: 501–512. © 2015 The Authors. Biotechnology and Bioengineering Published by Wiley Periodicals, Inc. PMID:26370186

  13. Functional characterization of the phospholipase C activity of ...

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Biosciences; Volume 33; Issue 2. Functional characterization of the ... by removing the phosphocholine. Furthermore, Rv3487c is expressed during infection as it exhibits significant humoral immunoreactivity with sera from children with tuberculosis, but not with that from adult patients.

  14. Covalent organic polymer functionalization of activated carbon surfaces through acyl chloride for environmental clean-up

    DEFF Research Database (Denmark)

    Mines, Paul D.; Thirion, Damien; Uthuppu, Basil

    2017-01-01

    Nanoporous networks of covalent organic polymers (COPs) are successfully grafted on the surfaces of activated carbons, through a series of surface modification techniques, including acyl chloride formation by thionyl chloride. Hybrid composites of activated carbon functionalized with COPs exhibit...

  15. Management with willow short rotation coppice increase the functional gene diversity and functional activity of a heavy metal polluted soil.

    Science.gov (United States)

    Xue, K; van Nostrand, J D; Vangronsveld, J; Witters, N; Janssen, J O; Kumpiene, J; Siebielec, G; Galazka, R; Giagnoni, L; Arenella, M; Zhou, J-Z; Renella, G

    2015-11-01

    We studied the microbial functional diversity, biochemical activity, heavy metals (HM) availability and soil toxicity of Cd, Pb and Zn contaminated soils, kept under grassland or short rotation coppice (SRC) to attenuate the risks associated with HM contamination and restore the soil ecological functions. Soil microbial functional diversity was analyzed by the GeoChip, a functional gene microarray containing probes for genes involved in nutrient cycling, metal resistance and stress response. Soil under SRC showed a higher abundance of microbial genes involved in C, N, P and S cycles and resistance to various HM, higher microbial biomass, respiration and enzyme activity rates, and lower HM availability than the grassland soil. The linkages between functional genes of soil microbial communities and soil chemical properties, HM availability and biochemical activity were also investigated. Soil toxicity and N, P and Pb availability were important factors in shaping the microbial functional diversity, as determined by CCA. We concluded that in HM contaminated soils the microbial functional diversity was positively influenced by SRC management through the reduction of HM availability and soil toxicity increase of nutrient cycling. The presented results can be important in predicting the long term environmental sustainability of plant-based soil remediation. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Patterns of functional enzyme activity in fungus farming ambrosia beetles

    Directory of Open Access Journals (Sweden)

    De Fine Licht Henrik H

    2012-06-01

    Full Text Available Abstract Introduction In wood-dwelling fungus-farming weevils, the so-called ambrosia beetles (Curculionidae: Scolytinae and Platypodinae, wood in the excavated tunnels is used as a medium for cultivating fungi by the combined action of digging larvae (which create more space for the fungi to grow and of adults sowing and pruning the fungus. The beetles are obligately dependent on the fungus that provides essential vitamins, amino acids and sterols. However, to what extent microbial enzymes support fungus farming in ambrosia beetles is unknown. Here we measure (i 13 plant cell-wall degrading enzymes in the fungus garden microbial consortium of the ambrosia beetle Xyleborinus saxesenii, including its primary fungal symbionts, in three compartments of laboratory maintained nests, at different time points after gallery foundation and (ii four specific enzymes that may be either insect or microbially derived in X. saxesenii adult and larval individuals. Results We discovered that the activity of cellulases in ambrosia fungus gardens is relatively small compared to the activities of other cellulolytic enzymes. Enzyme activity in all compartments of the garden was mainly directed towards hemicellulose carbohydrates such as xylan, glucomannan and callose. Hemicellulolytic enzyme activity within the brood chamber increased with gallery age, whereas irrespective of the age of the gallery, the highest overall enzyme activity were detected in the gallery dump material expelled by the beetles. Interestingly endo-β-1,3(4-glucanase activity capable of callose degradation was identified in whole-body extracts of both larvae and adult X. saxesenii, whereas endo-β-1,4-xylanase activity was exclusively detected in larvae. Conclusion Similar to closely related fungi associated with bark beetles in phloem, the microbial symbionts of ambrosia beetles hardly degrade cellulose. Instead, their enzyme activity is directed mainly towards comparatively more easily

  17. Physical activity and function in adolescents with chronic pain: A controlled study using actigraphy

    Science.gov (United States)

    Wilson, Anna C.; Palermo, Tonya M.

    2012-01-01

    Physical functioning is often impaired in adolescents with chronic pain, which has largely been demonstrated through subjective self-report measures. Actigraphy uses motion monitoring as an objective means for assessing one dimension of physical functioning, physical activity level. This study used subjective and objective measures to assess multiple dimensions of physical functioning in a clinical sample of adolescents with chronic pain (n = 78) and a comparison group of healthy adolescents (n = 59). Individual and pain characteristics were also examined as predictors of actigraphy variables within the chronic pain sample. Results indicated that adolescents with chronic pain demonstrate significant impairment in subjective measures of physical functioning and evidence lower levels of physical activity. Actigraphic measures of physical activity were moderately correlated with self-report measures of physical functioning. Individual characteristics, including adolescent age, sex, Body Mass Index percentile, were associated with physical activity levels among adolescents with chronic pain. Physical activity represents a distinct dimension of physical functioning. Assessing physical activity may provide additional description of physical functioning among adolescents with chronic pain, and may help identify targets for intervention in this population. Perspective This study demonstrates that adolescents with chronic pain have lower physical activity levels, as measured objectively via actigraphy, as well as poorer subjective reports of physical functioning, compared to healthy adolescents. Actigraphic measurement of physical activity provides objective source data about one dimension of physical functioning. PMID:22099608

  18. Functional neuroimaging of conversion disorder: The role of ancillary activation

    Directory of Open Access Journals (Sweden)

    Matthew J. Burke, MD

    2014-01-01

    Conclusions: Sensory conversion symptoms are associated with a pattern of abnormal cerebral activation comprising neural networks implicated in emotional processing and sensory integration. Further study of the roles and potential interplay of these networks may provide a basis for an underlying psychobiological mechanism of conversion disorder.

  19. Emergent Public Spaces: Generative Activities on Function Interpolation

    Science.gov (United States)

    Carmona, Guadalupe; Dominguez, Angeles; Krause, Gladys; Duran, Pablo

    2011-01-01

    This study highlights ways in which generative activities may be coupled with network-based technologies in the context of teacher preparation to enhance preservice teachers' cognizance of how their own experience as students provides a blueprint for the learning environments they may need to generate in their future classrooms. In this study, the…

  20. The human macrophage system: activity and functional morphology.

    Science.gov (United States)

    Michna, H

    1988-01-01

    Macrophages of humans could be extracted in large numbers from the connective tissue using a newly developed, not particularly difficult method. These macrophages were compared with the peritoneal macrophages of mice using light-, scanning and transmission electron-microscopic methods. The sterility of the cell suspension and the high yield of macrophages has allowed the first in vitro study of histiocytes to take place, in contrast to the classic 'microexudate-coated surface method'. The activity of the human in comparison with peritoneal murine macrophages has been evaluated using numerous histochemical and immunological techniques. These methods prove a modulation of the macrophage activity of healthy humans and mice under exemplary conditions of extremely strenuous physical exercising, in accordance with earlier experimental findings on animals alone. The degenerative changes which occur under these experimental conditions in the skeletal muscular system show an invasion of cells of the immune system, which are integrated into an explanation of the increased activity of macrophages. These results find their place in a new theoretical concept supporting the general validity of the co-operation of macrophages and other cells of the immune system in pathological degeneration and regeneration processes in the skeletal muscular system. It has been shown that the increased activity of human and murine macrophages brought about by extreme strenuous physical exercising, insofar as one is able to order them into a progressive scheme of stress happenings, fit very well into the concepts of the 'alarm reaction' phase. The activity of macrophages proves to be sensitive to the mediators of tumours of mesenchymal origin, with respect to the initial stage of phagocytosis, to the further biochemical deterioration, to the cytotoxicity and to the amount of cells; this, however, is not able to halt the rapid growth of sarcoma in a long term experiment. The proof of a weakened

  1. Changes in physical functioning in the Active Living Every Day program of the Active for Life Initiative®.

    Science.gov (United States)

    Baruth, Meghan; Wilcox, Sara; Wegley, Stacy; Buchner, David M; Ory, Marcia G; Phillips, Alisa; Schwamberger, Karen; Bazzarre, Terry L

    2011-09-01

    Physical activity can prevent or delay the onset of physical functional limitations in older adults. There are limited data that evidence-based physical activity interventions can be successfully translated into community programs and result in similar benefits for physical functioning. The purpose of this study is to measure the effects of the Active Living Every Day program on physical functioning and physical functional limitations in a diverse sample of older adults. As a part of the Active for Life initiative, the Council on Aging of Southwestern Ohio implemented Active Living Every Day (ALED), a group-based lifestyle behavior change program designed to increase physical activity. Performance-based physical functioning tests (30-s Chair Stand Test, eight Foot Up-and-Go Test, Chair Sit-and-Reach Test, 30-Foot Walk Test) were administered to participants at baseline and posttest. Baseline to post-program changes in physical functioning and impairment status were examined with repeated measures analysis of covariance. Interactions tested whether change over time differed according to race/ethnicity, body mass index (BMI), and baseline impairment status. Participants significantly increased their performance in all four physical functioning tests. The percentage of participants classified as "impaired" according to normative data significantly decreased over time. Physical functioning improved regardless of BMI, race/ethnicity, or baseline impairment status. ALED is an example of an evidenced-based physical activity program that can be successfully translated into community programs and result in significant and clinically meaningful improvements in performance-based measures of physical functioning.

  2. Recent Advances in Momordica charantia: Functional Components and Biological Activities

    OpenAIRE

    Jia, Shuo; Shen, Mingyue; Zhang, Fan; Xie, Jianhua

    2017-01-01

    Momordica charantia L. (M. charantia), a member of the Cucurbitaceae family, is widely distributed in tropical and subtropical regions of the world. It has been used in folk medicine for the treatment of diabetes mellitus, and its fruit has been used as a vegetable for thousands of years. Phytochemicals including proteins, polysaccharides, flavonoids, triterpenes, saponins, ascorbic acid and steroids have been found in this plant. Various biological activities of M. charantia have been report...

  3. Application of a novel functional gene microarray to probe the functional ecology of ammonia oxidation in nitrifying activated sludge.

    Directory of Open Access Journals (Sweden)

    Michael D Short

    Full Text Available We report on the first study trialling a newly-developed, functional gene microarray (FGA for characterising bacterial and archaeal ammonia oxidisers in activated sludge. Mixed liquor (ML and media biofilm samples from a full-scale integrated fixed-film activated sludge (IFAS plant were analysed with the FGA to profile the diversity and relative abundance of ammonia-oxidising archaea and bacteria (AOA and AOB respectively. FGA analyses of AOA and AOB communities revealed ubiquitous distribution of AOA across all samples - an important finding for these newly-discovered and poorly characterised organisms. Results also revealed striking differences in the functional ecology of attached versus suspended communities within the IFAS reactor. Quantitative assessment of AOB and AOA functional gene abundance revealed a dominance of AOB in the ML and approximately equal distribution of AOA and AOB in the media-attached biofilm. Subsequent correlations of functional gene abundance data with key water quality parameters suggested an important functional role for media-attached AOB in particular for IFAS reactor nitrification performance and indicate possible functional redundancy in some IFAS ammonia oxidiser communities. Results from this investigation demonstrate the capacity of the FGA to resolve subtle ecological shifts in key microbial communities in nitrifying activated sludge and indicate its value as a tool for better understanding the linkages between the ecology and performance of these engineered systems.

  4. The European ALARA network. Development, functioning and main activities

    International Nuclear Information System (INIS)

    Schmitt-Hannig, A.

    2009-01-01

    The new ICRP recommendations (ICRP 103), and in particular the detailed treatment of optimisation in the ICRP Publication 101, define optimisation of protection as a source-related process aimed at keeping the likelihood of incurred exposures, the number of people exposed and the magnitude of their individual doses as low as reasonably achievable, also below constraints, taking into account economic and societal factors. Practical implementation and further development of the ALARA principle has been achieved for many years now by the successful cooperation of experts from different European organisations; first as pioneers by establishing the European ALARA Network and then by enthusiastically supporting the activities of the network itself. This contribution presents the evolution, operation and key activities of the European ALARA Network (EAN) in the last years; the successful cooperation of experts from different professional backgrounds, advocating the ALARA principle in a range of radiation protection areas, and contributing to its further development by trading experience and networking. The interaction between the EAN and international organisations, which support the ALARA principle by including relevant activities in their work programmes, is described. (orig.)

  5. Microwave assisted bi-functional activation of -bromo-tert-alcohols

    Indian Academy of Sciences (India)

    -Bromo-tert-alcohols; microwave; bi-functional activation; ZnS; flavour compounds. ... A concurrent bi-functional activation of trans-vicinal bromo- and hydroxyl groups with ZnS is elucidated. This is a new ... Spice and Flavour Science Department, CSIR-Central Food Technological Research Institute, Mysore 570 020, India ...

  6. Intrinsic network activity in tinnitus investigated using functional MRI

    Science.gov (United States)

    Leaver, Amber M.; Turesky, Ted K.; Seydell-Greenwald, Anna; Morgan, Susan; Kim, Hung J.; Rauschecker, Josef P.

    2016-01-01

    Tinnitus is an increasingly common disorder in which patients experience phantom auditory sensations, usually ringing or buzzing in the ear. Tinnitus pathophysiology has been repeatedly shown to involve both auditory and non-auditory brain structures, making network-level studies of tinnitus critical. In this magnetic resonance imaging (MRI) study, we used two resting-state functional connectivity (RSFC) approaches to better understand functional network disturbances in tinnitus. First, we demonstrated tinnitus-related reductions in RSFC between specific brain regions and resting-state networks (RSNs), defined by independent components analysis (ICA) and chosen for their overlap with structures known to be affected in tinnitus. Then, we restricted ICA to data from tinnitus patients, and identified one RSN not apparent in control data. This tinnitus RSN included auditory-sensory regions like inferior colliculus and medial Heschl’s gyrus, as well as classically non-auditory regions like the mediodorsal nucleus of the thalamus, striatum, lateral prefrontal and orbitofrontal cortex. Notably, patients’ reported tinnitus loudness was positively correlated with RSFC between the mediodorsal nucleus and the tinnitus RSN, indicating that this network may underlie the auditory-sensory experience of tinnitus. These data support the idea that tinnitus involves network dysfunction, and further stress the importance of communication between auditory-sensory and fronto-striatal circuits in tinnitus pathophysiology. PMID:27091485

  7. Raman Optical Activity Spectra from Density Functional Perturbation Theory and Density-Functional-Theory-Based Molecular Dynamics.

    Science.gov (United States)

    Luber, Sandra

    2017-03-14

    We describe the calculation of Raman optical activity (ROA) tensors from density functional perturbation theory, which has been implemented into the CP2K software package. Using the mixed Gaussian and plane waves method, ROA spectra are evaluated in the double-harmonic approximation. Moreover, an approach for the calculation of ROA spectra by means of density functional theory-based molecular dynamics is derived and used to obtain an ROA spectrum via time correlation functions, which paves the way for the calculation of ROA spectra taking into account anharmonicities and dynamic effects at ambient conditions.

  8. Physical activity and functional limitations in older adults: the influence of self-efficacy and functional performance.

    Science.gov (United States)

    Mullen, Sean P; McAuley, Edward; Satariano, William A; Kealey, Melissa; Prohaska, Thomas R

    2012-05-01

    Data from the Healthy Aging Network (HAN) study (Prohaska, T., Eisenstein, A., Satariano, W., Hunter, R., Bayles, C., Kurtovich, E., … Ivey, S. [2009]. Walking and the preservation of cognitive function in older populations. The Gerontologist, 49[Suppl. 1], S86-S93; and Satariano, W., Ivey, S., Kurtovich, E., Kealey, M., Hubbard, A., Bayles, C., … Prohaska, T. [2010]. Lower-body function, neighborhoods, and walking in an older population. American Journal of Preventive Medicine, 38, 419-428.) were used to examine the relationships among physical activity, self-efficacy, functional performance, and limitations. Interviews were conducted within homes and senior centers in 4 geographic regions across the United States. Participants were 884 older adults (M age = 74.8; 77% female; 35% minority status) who completed measures of walking behavior, way-finding self-efficacy, walking self-efficacy, functional performance, functional limitations, and demographic characteristics. Path analysis within a covariance modeling framework revealed significant direct effects of walking on self-efficacy constructs, functional performance on functional limitations, and efficacy on limitations. Additionally, significant indirect effects were also found, including walking on limitations via walking self-efficacy and performance and walking self-efficacy on limitations via performance. Furthermore, we found support for invariance of the model across geographical grouping. Our findings provide further validation for an efficacy-based model of functional limitations. Walking-related efficacy may help reduce or possibly delay the onset of functional limitations.

  9. Executive Functions in Learning Processes: Do They Benefit from Physical Activity?

    Science.gov (United States)

    Barenberg, Jonathan; Berse, Timo; Dutke, Stephan

    2011-01-01

    As executive functions play an essential role in learning processes, approaches capable of enhancing executive functioning are of particular interest to educational psychology. Recently, the hypothesis has been advanced that executive functioning may benefit from changes in neurobiological processes induced by physical activity. The present…

  10. Spontaneous activity in the developing mammalian retina: Form and function

    Science.gov (United States)

    Butts, Daniel Allison

    Spontaneous neuronal activity is present in the immature mammalian retina during the initial stages of visual system development, before the retina is responsive to light. This activity consists of bursts of action potentials fired by retinal ganglion cells, and propagates in a wavelike manner across the inner plexiform layer of the retina. Unlike waves in other neural systems, retinal waves have large variability in both their rate and direction of propagation, and individual waves only propagate across small regions of the retina. The unique properties of retinal activity arise from dynamic processes within the developing retina, and produce characteristic spatiotemporal properties. These spatiotemporal properties are of particular interest, since they are believed to play a role in visual system development. This dissertation addresses the complex spatiotemporal patterning of the retinal waves from two different perspectives. First, it proposes how the immature circuitry of the developing retina generates these patterns of activity. In order to reproduce the distinct spatiotemporal properties observed in experiments, a model of the immature retinal circuitry must meet certain requirements, which are satisfied by a coarse-grained model of the developing retina that we propose. Second, this dissertation addresses how the particular spatiotemporal patterning of the retinal waves provides information to the rest of the visual system and, as a result, can be used to guide visual system development. By measuring the properties of this information, we place constraints on the developmental mechanisms that use this activity, and show how the particular spatiotemporal properties of the retinal waves provide this information. Together, this dissertation demonstrates how the apparent complexity of retinal wave patterning can be understood both through the immature circuitry that generates it, and through the developmental mechanisms that may use it. The first three

  11. Feelings of well being in elderly people: relationship to physical activity and physical function.

    Science.gov (United States)

    Garatachea, Nuria; Molinero, Olga; Martínez-García, Raquel; Jiménez-Jiménez, Rodrigo; González-Gallego, Javier; Márquez, Sara

    2009-01-01

    The aim of the research was to investigate in a sample of Spanish elderly whether measures of physical activity and physical function are related to feelings of well being, and whether level of dependence is a moderator in the relation of well being, physical activity and physical function. The sample was a cohort of 151 elderly people (89 women and 62 men, aged 60-98 years) from the North of Spain. Participants completed surveys including demographic characteristics, and measures of physical activity (Yale Physical Activity Survey, YPAS), instrumental activities of daily living (Barthel Index, BI) and well being (Psychological Well Being Scale, from Spanish: Escala de Bienestar Psicológico=EBP). Components of the physical function were measured by the Senior Fitness Test (SFT). Upper and lower body strength, dynamic balance, aerobic endurance, self-reported weekly energy expenditure and physical activity total time were significantly correlated with both Material and Subjective well being. All components of physical function were significantly impaired in dependent subjects when compared to independent individuals of the same sex and physical activity category. Significant differences were also observed in Subjective well being among less active dependent or independent individuals. In conclusion, physical function and physical activity are related to feelings of well being, and results emphasize the positive functional and psychological effects of physical activity in dependent subjects.

  12. Correlation between adolescents low back pain, trunk muscle functions and physical activity

    OpenAIRE

    Tuzikaitė, Gintarė

    2016-01-01

    Correlation Between Adolescents Low Back Pain, Trunk Muscle Functions and Physical Activity The aim of research work: The aim of this study was to evaluate the relationship between adolescents low back pain, trunk muscle functions and physical activity. Tasks of work: 1. To assess and compare the lumbar proprioception in subjects with and without low back pain. 2. To assess and compare the trunk muscle functions in subjects with and without low back pain. 3. To assess and compare the physical...

  13. Altered activity and functional connectivity of superior temporal gyri in anxiety disorders: A functional magnetic resonance imaging study

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Xiaohu; Xi, Qian; Wang, Peijun; Li, Chunbo [Tong Ji Hospital of Tong Ji University, Shanghai (China); He, Hongjian [Bio-X lab, Dept. of Physics, Zhe Jiang University, Hangzhou (China)

    2014-08-15

    The prior functional MRI studies have demonstrated significantly abnormal activity in the bilateral superior temporal gyrus (STG) of anxiety patients. The purpose of the current investigation was to determine whether the abnormal activity in these regions was related to a loss of functional connectivity between these regions. Ten healthy controls and 10 anxiety patients underwent noninvasive fMRI while actively listening to emotionally neutral words alternated by silence (Task 1) or threat-related words (Task 2). The participants were instructed to silently make a judgment of each word's valence (i.e., unpleasant, pleasant, or neutral). A coherence analysis was applied to the functional MRI data to examine the functional connectivity between the left and the right STG, which was selected as the primary region of interest on the basis of our prior results. The data demonstrated that the anxiety patients exhibited significantly increased activation in the bilateral STG than the normal controls. The functional connectivity analysis indicated that the patient group showed significantly decreased degree of connectivity between the bilateral STG during processing Task 2 compared to Task 1 (t = 2.588, p = 0.029). In addition, a significantly decreased connectivity was also observed in the patient group compared to the control group during processing Task 2 (t = 2.810, p = 0.012). Anxiety patients may exhibit increased activity of the STG but decreased functional connectivity between the left and right STG, which may reflect the underlying neural abnormality of anxiety disorder, and this will provide new insights into this disease.

  14. Altered activity and functional connectivity of superior temporal gyri in anxiety disorders: A functional magnetic resonance imaging study

    International Nuclear Information System (INIS)

    Zhao, Xiaohu; Xi, Qian; Wang, Peijun; Li, Chunbo; He, Hongjian

    2014-01-01

    The prior functional MRI studies have demonstrated significantly abnormal activity in the bilateral superior temporal gyrus (STG) of anxiety patients. The purpose of the current investigation was to determine whether the abnormal activity in these regions was related to a loss of functional connectivity between these regions. Ten healthy controls and 10 anxiety patients underwent noninvasive fMRI while actively listening to emotionally neutral words alternated by silence (Task 1) or threat-related words (Task 2). The participants were instructed to silently make a judgment of each word's valence (i.e., unpleasant, pleasant, or neutral). A coherence analysis was applied to the functional MRI data to examine the functional connectivity between the left and the right STG, which was selected as the primary region of interest on the basis of our prior results. The data demonstrated that the anxiety patients exhibited significantly increased activation in the bilateral STG than the normal controls. The functional connectivity analysis indicated that the patient group showed significantly decreased degree of connectivity between the bilateral STG during processing Task 2 compared to Task 1 (t = 2.588, p = 0.029). In addition, a significantly decreased connectivity was also observed in the patient group compared to the control group during processing Task 2 (t = 2.810, p = 0.012). Anxiety patients may exhibit increased activity of the STG but decreased functional connectivity between the left and right STG, which may reflect the underlying neural abnormality of anxiety disorder, and this will provide new insights into this disease.

  15. Functions of Cross-Border Economic Activities in Skouw Sae Community, Jayapura City

    OpenAIRE

    La Usman; Syafri Sairin

    2017-01-01

    Cross-border economic activities are often done by people of Skouw Sae Village, Muara Tami District, Jayapura City to Wutung Village, Vanimo, Papua New Guinea. This study attempts to analyze the functions of economic activity in this community. Data were processed using qualitative analysis. The results of this study found seven functions of cross-border economic activities. First, to meet nutritional needs of the family. Second, to meet reproductive needs for family continuity. Third, to mee...

  16. Relationship between gross motor function and the function, activity and participation components of the International Classification of Functioning in children with spastic cerebral palsy.

    Science.gov (United States)

    Lee, Byoung-Hee

    2017-10-01

    [Purpose] This study aimed to evaluate the relationship between gross motor function, measured using the Gross Motor Function Measure (GMFM), Gross Motor Function Classification System (GMFCS), Manual Ability Classification System (MACS), and Functional Independence Measure for Children (WeeFIM), and Function, and Activity and Participation components of the International Classification of Functioning, Disability, and Health-Child and Youth Check List (ICF-CY) in children with spastic cerebral palsy (CP). [Subjects and Methods] Seventy-seven children with spastic CP participated in the study. The GMFM, GMFCS, MACS, and WeeFIM were administered in their entirety to patients without orthoses or mobility aids. The ICF-CY was used to evaluate the degree of disability and health. [Results] The score of the ICF component of Activity and Participation had a significantly strong correlation with the scores of GMFM, GMFCS, MACS, WeeFIM, and ICF component of Function. [Conclusion] When establishing a treatment plan for children with spastic CP, the children's physical abilities, and their limitation in activity, performance, and participation, which would be measured using the ICF-CY, should be taken into consideration.

  17. Sympathetic activation and baroreflex function during intradialytic hypertensive episodes.

    Directory of Open Access Journals (Sweden)

    Dvora Rubinger

    Full Text Available BACKGROUND: The mechanisms of intradialytic increases in blood pressure are not well defined. The present study was undertaken to assess the role of autonomic nervous system activation during intradialytic hypertensive episodes. METHODOLOGY/PRINCIPAL FINDINGS: Continuous interbeat intervals (IBI and systolic blood pressure (SBP were monitored during hemodialysis in 108 chronic patients. Intradialytic hypertensive episodes defined as a period of at least 10 mmHg increase in SBP between the beginning and the end of a dialysis session or hypertension resistant to ultrafiltration occurring during or immediately after the dialysis procedure, were detected in 62 out of 113 hemodialysis sessions. SBP variability, IBI variability and baroreceptor sensitivity (BRS in the low (LF and high (HF frequency ranges were assessed using the complex demodulation technique (CDM. Intradialytic hypertensive episodes were associated with an increased (n = 45 or decreased (n = 17 heart rate. The maximal blood pressure was similar in both groups. In patients with increased heart rate the increase in blood pressure was associated with marked increases in SBP and IBI variability, with suppressed BRS indices and enhanced sympatho-vagal balance. In contrast, in those with decreased heart rate, there were no significant changes in the above parameters. End-of-dialysis blood pressure in all sessions associated with hypertensive episode was significantly higher than in those without such episodes. In logistic regression analysis, predialysis BRS in the low frequency range was found to be the main predictor of intradialytic hypertension. CONCLUSION/SIGNIFICANCE: Our data point to sympathetic overactivity with feed-forward blood pressure enhancement as an important mechanism of intradialytic hypertension in a significant proportion of patients. The triggers of increased sympathetic activity during hemodialysis remain to be determined. Intradialytic hypertensive episodes

  18. Relationship between neuromuscular body functions and upper extremity activity in children with cerebral palsy.

    Science.gov (United States)

    Braendvik, Siri M; Elvrum, Ann-Kristin G; Vereijken, Beatrix; Roeleveld, Karin

    2010-02-01

    Our aim was to investigate the relationship between the dimensions of neuromuscular body function and elbow, forearm, and hand activity in the upper extremities in children/adolescents with spastic cerebral palsy (CP), within the framework of the World Health Organization International Classification of Functioning, Disability and Health. Twenty-three participants (10 males, 13 females, mean age 13y, SD 3y, range 8-18y) with spastic CP (21 with hemiplegia, two with diplegia) at Manual Ability Classification System levels I to III participated in the study. Neuromuscular body function measures were (1) muscle strength in the elbow, forearm, and grip, (2) muscle tone in elbow flexors and forearm supinators, (3) active supination range and elbow extension range, and (4) force control at submaximal level in elbow flexion. Activity measures were actual use of the affected hand in bimanual activities (Assisting Hand Assessment) and instructed use of the affected hand (Melbourne Assessment of Unilateral Upper Limb Function). Nearly all the neuromuscular body function variables were significantly correlated with activity. The combination of active supination range and strength explained 74% of the variance in actual use, and the combination of active supination range and force control explained 74% of the variance in instructed use. In high-functioning children and adolescents with CP, limited active supination range and difficulties in generating and modulating force are strongly related to limitations in hand activity. Further studies are needed to establish cause and effect in this relationship.

  19. Electrochemically active functionalization of graphene for development of prototype biosensing devices

    DEFF Research Database (Denmark)

    Halder, Arnab; Ulstrup, Jens; Chi, Qijin

    support for chemosensors and biosensors. Functionalization of graphene can further transform this 2D material into various versatile platforms for different applications. In this presentation, we will address some of our recent investigations: (1) electrochemically active functionalization of graphene...... nanosheets, (2) loading of different enzymes on functionalized graphene matrix, and (3) electrochemical performances of the functionalized nanaohybrid materials based prototype sensors. These latest advancements could be crucial for the design and fabrication of low-cost, flexible and disposable biosensors....

  20. Adherence to physical activity guidelines and functional fitness of elderly women, using objective measurement.

    Science.gov (United States)

    Nawrocka, Agnieszka; Mynarski, Władysław; Cholewa, Jarosław

    2017-12-23

    Physical activity is an important factor in maintaining the health and functional fitness of elderly people. The aim of the study was to determine the number of senior women meeting the physical activity guidelines, and their level of functional fitness in comparison to women who are not sufficiently physically active. The study involved 61 women, aged 60-75. Physical activity was monitored on seven consecutive days of the week, using a triaxial accelerometer ActiGraph GT3X. Results of the assessment of physical activity were verified against the Global Recommendations of Physical Activity for Health. The Senior Fitness Test (Fullerton Test) was used to evaluate functional fitness. In the studied group, 36.1% achieved the recommended level of physical activity. All those examined mainly undertook physical activity of low intensity. Vigorous physical activity during the week was noted in only 6 seniors. Women who met the recommendations of physical activity achieved significantly better results in test trials, e.g. Chair Stands, Up and Go, Six Minute Step Test. Adherence to physical activity guidelines was associated with better functional fitness of older women. However, less than half of the examined seniors met the Global Recommendations on Physical Activity for Health.

  1. The role of visual feedback in respiratory muscle activation and pulmonary function.

    Science.gov (United States)

    Park, Han-Kyu; Kim, Yeong-Ju; Kim, Tae-Ho

    2015-09-01

    [Purpose] It is well known that visual feedback is an important factor contributing to balance and postural control. Nevertheless, there has been little discussion about the effects of visual feedback on pulmonary function. This study was conducted to investigate the role of visual feedback on respiratory muscle activation and pulmonary function. [Subjects and Methods] The subjects were 37 healthy adults who consented to participate in this study. The study measured the muscular activation of the trunk and pulmonary function according to the absence or presence of visual feedback. [Results] The results revealed significant changes in muscular activation and pulmonary function with the use of visual feedback. [Conclusion] These findings suggest that visual feedback may play a role in increasing respiratory muscle activity and pulmonary function.

  2. Cognitive function and the agreement between self-reported and accelerometer-accessed physical activity.

    Science.gov (United States)

    Herbolsheimer, Florian; Riepe, Matthias W; Peter, Richard

    2018-02-21

    Numerous studies have reported weak or moderate correlations between self-reported and accelerometer-assessed physical activity. One explanation is that self-reported physical activity might be biased by demographic, cognitive or other factors. Cognitive function is one factor that could be associated with either overreporting or underreporting of daily physical activity. Difficulties in remembering past physical activities might result in recall bias. Thus, the current study examines whether the cognitive function is associated with differences between self-reported and accelerometer-assessed physical activity. Cross-sectional data from the population-based Activity and Function in the Elderly in Ulm study (ActiFE) were used. A total of 1172 community-dwelling older adults (aged 65-90 years) wore a uniaxial accelerometer (activPAL unit) for a week. Additionally, self-reported physical activity was assessed using the LASA Physical Activity Questionnaire (LAPAQ). Cognitive function was measured with four items (immediate memory, delayed memory, recognition memory, and semantic fluency) from the Consortium to Establish a Registry for Alzheimer's Disease Total Score (CERAD-TS). Mean differences of self-reported and accelerometer-assessed physical activity (MPA) were associated with cognitive function in men (r s  = -.12, p = .002) but not in women. Sex-stratified multiple linear regression analyses showed that MPA declined with high cognitive function in men (β = -.13; p = .015). Results suggest that self-reported physical activity should be interpreted with caution in older populations, as cognitive function was one factor that explained the differences between objective and subjective physical activity measurements.

  3. Organized Sport Participation and Physical Activity Levels among Adolescents with Functional Limitations

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    Kwok Ng

    2017-10-01

    Full Text Available Sufficient and regular physical activity is considered a protective factor, reducing the onset of secondary disability conditions in adolescents with chronic diseases and functional limitations. The aim of this study was to explore whether participation in organized sport may be associated to higher levels of physical activity in adolescents with functional limitations, based on a national representative sample. Data from the Health Behaviour in School-aged Children (HBSC study collected in Finland from two data collection rounds (2002 and 2010 were conducted and pooled from adolescents aged between 13 and 15 years old with functional limitations (n = 1041. Differences in self-reported physical activity over the past week and participation in organized sport activity were analysed for each function. Overall, four in ten (n = 413 participated in organized sport and were significantly (p < 0.001 more physically active (mean = 4.92days, SD = 1.81 than their non-participating (mean = 3.29, SD = 1.86 peers with functional limitations. Despite low population prevalence, adolescents with epilepsy or visual impairments were the least active if they were not participating in organized sport, yet were the most active if they were involved in organized sport. Participating in organized sport appears to be an important factor promoting resources for maintaining recommended levels of physical activity in Finnish adolescents with functional limitations.

  4. Social Activity and Cognitive Functioning Over Time: A Coordinated Analysis of Four Longitudinal Studies

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    Cassandra L. Brown

    2012-01-01

    Full Text Available Social activity is typically viewed as part of an engaged lifestyle that may help mitigate the deleterious effects of advanced age on cognitive function. As such, social activity has been examined in relation to cognitive abilities later in life. However, longitudinal evidence for this hypothesis thus far remains inconclusive. The current study sought to clarify the relationship between social activity and cognitive function over time using a coordinated data analysis approach across four longitudinal studies. A series of multilevel growth models with social activity included as a covariate is presented. Four domains of cognitive function were assessed: reasoning, memory, fluency, and semantic knowledge. Results suggest that baseline social activity is related to some, but not all, cognitive functions. Baseline social activity levels failed to predict rate of decline in most cognitive abilities. Changes in social activity were not consistently associated with cognitive functioning. Our findings do not provide consistent evidence that changes in social activity correspond to immediate benefits in cognitive functioning, except perhaps for verbal fluency.

  5. Mental Health in Multiple Sclerosis Patients without Limitation of Physical Function: The Role of Physical Activity.

    Science.gov (United States)

    Tallner, Alexander; Waschbisch, Anne; Hentschke, Christian; Pfeifer, Klaus; Mäurer, Mathias

    2015-07-02

    Multiple sclerosis (MS) patients, in general, show reduced physical function, physical activity, and quality of life. Positive associations between physical activity and quality of life have been reported. In particular, we were interested in the relation between physical activity and mental health in MS patients without limitation of physical function, since limitations of physical function may influence both physical activity and quality of life. Assessment comprised the Baecke questionnaire on physical activity, the Short Form 36 Health Survey (SF-36), and Beck Depression Inventory (BDI). We ranked our sample according to physical activity into four groups and performed an ANOVA to analyze the relationship between levels of physical activity and health-related quality of life (HRQoL). Then we performed a subgroup analysis and included patients with unlimited walking distance and a score of less than 18 in the BDI. Most active vs. inactive patients were compared for the mental subscales of the SF-36 and depression scores. From 632 patients, 265 met inclusion criteria and hence quartiles were filled with 67 patients each. Active and inactive patients did not differ considerably in physical function. In contrast, mental subscales of the SF-36 were higher in active patients. Remarkable and significant differences were found regarding vitality, general health perception, social functioning and mental health, all in favor of physically active patients. Our study showed that higher physical activity is still associated with higher mental health scores even if limitations of physical function are accounted for. Therefore, we believe that physical activity and exercise have considerable health benefits for MS patients.

  6. Mental Health in Multiple Sclerosis Patients without Limitation of Physical Function: The Role of Physical Activity

    Directory of Open Access Journals (Sweden)

    Alexander Tallner

    2015-07-01

    Full Text Available Multiple sclerosis (MS patients, in general, show reduced physical function, physical activity, and quality of life. Positive associations between physical activity and quality of life have been reported. In particular, we were interested in the relation between physical activity and mental health in MS patients without limitation of physical function, since limitations of physical function may influence both physical activity and quality of life. Assessment comprised the Baecke questionnaire on physical activity, the Short Form 36 Health Survey (SF-36, and Beck Depression Inventory (BDI. We ranked our sample according to physical activity into four groups and performed an ANOVA to analyze the relationship between levels of physical activity and health-related quality of life (HRQoL. Then we performed a subgroup analysis and included patients with unlimited walking distance and a score of less than 18 in the BDI. Most active vs. inactive patients were compared for the mental subscales of the SF-36 and depression scores. From 632 patients, 265 met inclusion criteria and hence quartiles were filled with 67 patients each. Active and inactive patients did not differ considerably in physical function. In contrast, mental subscales of the SF-36 were higher in active patients. Remarkable and significant differences were found regarding vitality, general health perception, social functioning and mental health, all in favor of physically active patients. Our study showed that higher physical activity is still associated with higher mental health scores even if limitations of physical function are accounted for. Therefore, we believe that physical activity and exercise have considerable health benefits for MS patients.

  7. Objective measurement of function following lumbar spinal stenosis decompression reveals improved functional capacity with stagnant real-life physical activity.

    Science.gov (United States)

    Smuck, Matthew; Muaremi, Amir; Zheng, Patricia; Norden, Justin; Sinha, Aman; Hu, Richard; Tomkins-Lane, Christy

    2018-01-01

    Lumbar spinal stenosis (LSS) is a prevalent and costly condition associated with significant dysfunction. Alleviation of pain and improvement of function are the primary goals of surgical intervention. Although prior studies have measured subjective improvements in function after surgery, few have examined objective markers of functional improvement. We aimed to objectively measure and quantify changes in physical capacity and physical performance following surgical decompression of LSS. Prospective cohort study. Thirty-eight patients with LSS determined by the treating surgeon's clinical and imaging evaluation, and who were scheduled for surgical treatment, were consecutively recruited at two academic medical facilities, with 28 providing valid data for analysis at baseline and 6 months after surgery. Before surgery and at 6 months after surgery, participants provided 7 days of real-life physical activity (performance) using ActiGraph accelerometers; completed two objective functional capacity measures, the Short Physical Performance Battery and Self-Paced Walking Test; and completed three subjective functional outcome questionnaires, Oswestry Disability Index, Spinal Stenosis Symptom Questionnaire, and Short-Form 36. Physical activity, as measured by continuous activity monitoring, was analyzed as previously described according to the 2008 American Physical Activity Guidelines. Paired t tests were performed to assess for postsurgical changes in all questionnaire outcomes and all objective functional capacity measures. Chi-square analysis was used to categorically assess whether patients were more likely to meet these physical activity recommendations after surgery. Participants were 70.1 years old (±8.9) with 17 females (60.7%) and an average body mass index of 28.4 (±6.2). All subjective measures (Oswestry Disability Index, Spinal Stenosis Symptom Questionnaire, and Short-Form 36) improved significantly at 6 months after surgery, as did objective functional

  8. Functional exchange of components between light-activated photoreceptor phosphodiesterase and hormone-activated adenylate cyclase systems

    Energy Technology Data Exchange (ETDEWEB)

    Bitensky, M.W.; Wheeler, M.A.; Rasenick, M.M.; Yamazaki, A.; Stein, P.J.; Halliday, K.R.; Wheeler, G.L.

    1982-06-01

    Previous studies have noted profound similarities between the regulation of light-activated (3',5'-cyclic-nucleotide 5'-nucleotidohydrolase, EC 3.1.4.17) in retinal rods and hormone-activated adenylate cyclase (ATP pyrophosphate-lyase (cyclizing), EC 4.6.1.1) in a variety of tissues. We report ere the functional exchange of components isolated from the photoreceptor system, which displayed predicted functional characteristics when incubated with recipient adenylate cyclase systems from rat cerebral cortical and hypothalamic synaptic membranes and frog erythrocyte ghosts. We demonstrate functional exchange of photoreceptor components at each of three loci: the hormone receptor, the GTP-binding protein (GBP), and the catalytic moiety of adenylate cyclase. Illuminated (but not unilluminated) rhodopsin was found to mimic the hormone-receptor complex, causing GTP-dependent activation of adenylate cyclase. The photoreceptor GBP complexed with guanosine 5'-(..beta..,..gamma..)imidotriphosphate (p(NH)ppG) produced a marked activation of recipient adenylate cyclase systems. Much smaller activation was observed when GBP was not complexed with p(NH)ppG. A heat-stable photoreceptor phosphodiesterase inhibitor reduced both basal and Mn/sup 2 +/-activated adenylate cyclase activites and this inhibition was reversed by photoreceptor GBPp(NH)ppG. These data demonstrate a remarkable functional compatibility between subunits of both systems and furthermore imply that specialized peptide domains responsible for protein-protein interactions are highly conserved.

  9. Aerobic exercise promotes executive functions and impacts functional neural activity among older adults with vascular cognitive impairment.

    Science.gov (United States)

    Hsu, Chun Liang; Best, John R; Davis, Jennifer C; Nagamatsu, Lindsay S; Wang, Shirley; Boyd, Lara A; Hsiung, Gy Robin; Voss, Michelle W; Eng, Janice Jennifer; Liu-Ambrose, Teresa

    2018-02-01

    Vascular cognitive impairment (VCI) results from cerebrovascular disease, and worldwide, it is the second most common type of cognitive dysfunction. While targeted aerobic training is a promising approach to delay the progression of VCI by reducing cardiometabolic risk factors, few randomised controlled trials to date have specifically assessed the efficacy of aerobic training on cognitive and brain outcomes in this group at risk for functional decline. To examine the effect of moderate-intensity aerobic training on executive functions and functional neural activity among older adults with mild subcortical ischaemic VCI (SIVCI). Older adults with mild SIVCI were randomly assigned to: (1) 6-month, 3×/week aerobic training (n=10) or (2) usual care (control; n=11). Participants completed functional MRI (fMRI) at baseline and trial completion. During the fMRI sessions, behavioural performance on the Eriksen flanker task and task-evoked neural activity were assessed. At trial completion, after adjusting for baseline general cognition, total white matter lesion volume and flanker performance, compared with the control group, the aerobic training group significantly improved flanker task reaction time. Moreover, compared with the controls, the aerobic training group demonstrated reduced activation in the left lateral occipital cortex and right superior temporal gyrus. Reduced activity in these brain regions was significantly associated with improved (ie, faster) flanker task performance at trial completion. Aerobic training among older adults with mild SIVCI can improve executive functions and neural efficiency of associated brain areas. Future studies with greater sample size should be completed to replicate and extend these findings. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  10. The Association Between Physical Activity and Cognitive Function With Considerations by Social Risk Status.

    Science.gov (United States)

    Frith, Emily; Loprinzi, Paul D

    2017-11-01

    We evaluated the association between physical activity and cognitive function among a national sample of the broader U.S. adult population, with consideration by social risk. Data from the 1999-2002 National Health and Nutrition Examination Survey (NHANES) were used to identify 2031 older adults, ages 60-85. Social risk was classified by measuring four NHANES variables, namely poverty level, education, minority status, and social living status, which were graded on a scale of 0-4, with higher scores corresponding with higher social risk. The Digit Symbol Substitution Test (DSST) was used to assess cognitive function. Physical activity was assessed via a validated self-report questionnaire. After adjustments, meeting physical activity guidelines (vs not) was associated with greater cognitive function (β = 3.0, 95% CI [1.5, 4.4], p social risk status was also independently associated with cognitive function. Meeting physical activity guidelines (vs. not) was not associated with higher cognitive function among those with a social risk score of of 3 (β = -0.01; 95% CI [-6.3, 6.4], p = 0.99) or a social risk score of 4 (β = -6.8, 95% CI [-15.7, 2.0], p = 0.12). In this national sample of older adults, meeting physical activity guidelines, and degree of social risk were independently associated with cognitive function. However, physical activity was not associated with cognitive function among older adults with the highest degree of social risk.

  11. Fitness, but not physical activity, is related to functional integrity of brain networks associated with aging.

    Science.gov (United States)

    Voss, Michelle W; Weng, Timothy B; Burzynska, Agnieszka Z; Wong, Chelsea N; Cooke, Gillian E; Clark, Rachel; Fanning, Jason; Awick, Elizabeth; Gothe, Neha P; Olson, Erin A; McAuley, Edward; Kramer, Arthur F

    2016-05-01

    Greater physical activity and cardiorespiratory fitness are associated with reduced age-related cognitive decline and lower risk for dementia. However, significant gaps remain in the understanding of how physical activity and fitness protect the brain from adverse effects of brain aging. The primary goal of the current study was to empirically evaluate the independent relationships between physical activity and fitness with functional brain health among healthy older adults, as measured by the functional connectivity of cognitively and clinically relevant resting state networks. To build context for fitness and physical activity associations in older adults, we first demonstrate that young adults have greater within-network functional connectivity across a broad range of cortical association networks. Based on these results and previous research, we predicted that individual differences in fitness and physical activity would be most strongly associated with functional integrity of the networks most sensitive to aging. Consistent with this prediction, and extending on previous research, we showed that cardiorespiratory fitness has a positive relationship with functional connectivity of several cortical networks associated with age-related decline, and effects were strongest in the default mode network (DMN). Furthermore, our results suggest that the positive association of fitness with brain function can occur independent of habitual physical activity. Overall, our findings provide further support that cardiorespiratory fitness is an important factor in moderating the adverse effects of aging on cognitively and clinically relevant functional brain networks. Copyright © 2015 Elsevier Inc. All rights reserved.

  12. Exercise and social activity improve everyday function in long-term care residents.

    Science.gov (United States)

    Lorenz, Rebecca A; Gooneratne, Nalaka; Cole, Catherine S; Kleban, Morton H; Kalra, Gurpreet K; Richards, Kathy C

    2012-06-01

    This study examined the effects of high-intensity resistance strength training and walking (E), individualized social activity (SA), and resistance training and walking combined with social activity (ESA) on everyday function in long-term care (LTC) residents and explored the relationship between change in everyday function and change in sleep. The study used data from The Effect of Activities and Exercise on Sleep, a randomized controlled trial. Residential LTC facilities. A total of 119 participants who had measures of everyday function and sleep at baseline and postintervention. The E group exercised 5 days a week. The SA group was involved in social activities 5 days a week. The ESA group received both E and SA interventions. The usual care (UC) control group participated in usual activities. Everyday function was measured by the Nursing Home Physical Performance Test. Nighttime sleep was measured by attended polysomnography. The UC and SA groups showed a decline in everyday function, whereas the E and ESA groups showed improvement. There were statistically significant differences between the groups, with pairwise comparisons showing significant improvements in the ESA group over the SA group (95% confidence interval, -3.94 to -0.97) and the UC group (95% confidence interval, -3.69 to -0.64). No relationship was found between change in everyday function and change in sleep. Seven weeks of high-intensity resistance strength training and walking, combined with individualized social activities (ESA), improved everyday function among LTC residents, independent of change in sleep.

  13. FUNCTIONAL ANALYSIS OF FUTURE MUSIC ART TEACHERS’ TRAINING FOR SINGING ACTIVITY OF COMPREHENSIVE SCHOOL SENIOR STUDENTS

    Directory of Open Access Journals (Sweden)

    Ma Chen

    2017-04-01

    Full Text Available In the article the functional analysis of future music art teachers’ training for singing activity of comprehensive school senior students is depicted. This issue is very important because improving educators and musicians’ training contributes not only to professional selfactualisation, but also to young generation’s encouraging for thorough learning music art works and their creative development in the process of group music tuitions. Extracurricular singing activity also plays an important part. It reveals art images to students, enriching creativity experience, forms the spiritual world, develops independent thinking, awakens creativity. The author points out the main functions of future music art teachers’ training. They are system and value, information, communication, creative and transformative, projective functions. The special attention is paid to characterizing the features of each function. The author claims that system and value function relates to the necessity to analyze the results of the educational process that contributes to productive solving problems by students and main tasks of music training. Information function is a subject background of art music teachers’ and pedagogical activities. Communicative function is realized in a teacher’s ability to develop the student’ initiative to plan cooperative activities, to be able to distribute duties, to carry out instructions, to coordinate cooperative activities, to create special situations for the implementation of educational influence. The analysis of pedagogical and methodological literature shows that The creative and transformative function is manifested in the creative use of pedagogical and methodological ideas in specific pedagogical conditions. The projective function is thought to promote the most complete realization of content of comprehensive and art education. Functional analysis of students’ training of art faculties at pedagogical universities to

  14. Trajectory of change in pain, depression, and physical functioning after physical activity adoption in fibromyalgia.

    Science.gov (United States)

    Steiner, Jennifer L; Bigatti, Silvia M; Ang, Dennis C

    2015-07-01

    Fibromyalgia is associated with widespread pain, depression, and declines in physical functioning. The purpose of this study was to examine the trajectory of these symptoms over time related to physical activity adoption and maintenance via motivational interviewing versus education, to increase physical activity. There were no treatment group differences; we divided the sample (n = 184) based on changes in physical activity. Repeated measures analyses demonstrated differential patterns in depression, pain, and physical functioning at 24 and 36 weeks. Findings suggest increased physical activity may serve as a multiple-target intervention that provides moderate to large, long-lasting benefits for individuals with fibromyalgia. © The Author(s) 2013.

  15. Mutations in the catalytic loop HRD motif alter the activity and function of Drosophila Src64.

    Directory of Open Access Journals (Sweden)

    Taylor C Strong

    Full Text Available The catalytic loop HRD motif is found in most protein kinases and these amino acids are predicted to perform functions in catalysis, transition to, and stabilization of the active conformation of the kinase domain. We have identified mutations in a Drosophila src gene, src64, that alter the three HRD amino acids. We have analyzed the mutants for both biochemical activity and biological function during development. Mutation of the aspartate to asparagine eliminates biological function in cytoskeletal processes and severely reduces fertility, supporting the amino acid's critical role in enzymatic activity. The arginine to cysteine mutation has little to no effect on kinase activity or cytoskeletal reorganization, suggesting that the HRD arginine may not be critical for coordinating phosphotyrosine in the active conformation. The histidine to leucine mutant retains some kinase activity and biological function, suggesting that this amino acid may have a biochemical function in the active kinase that is independent of its side chain hydrogen bonding interactions in the active site. We also describe the phenotypic effects of other mutations in the SH2 and tyrosine kinase domains of src64, and we compare them to the phenotypic effects of the src64 null allele.

  16. Size matters to function: Brain volume correlates with intrinsic brain activity across healthy individuals.

    Science.gov (United States)

    Qing, Zhao; Gong, Gaolang

    2016-10-01

    A fundamental issue in neuroscience is to understand the structural substrates of neural activities. Intrinsic brain activity has been increasingly recognized as an important functional activity mode and is tightly linked with various cognitive functions. Structurally, cognitive functions have also shown a relation with brain volume/size. Therefore, an association between intrinsic brain activities and brain volume/size can be hypothesized, and brain volume/size may impact intrinsic brain activity in human brains. The present study aimed to explicitly investigate this brain structure-function relationship using two large independent cohorts of 176 and 236 young adults. Structural-MRI was performed to estimate the brain volume, and resting-state functional-MRI was applied to extract the amplitude of low-frequency fluctuations (ALFF), an imaging measure of intrinsic brain activity. Intriguingly, our results revealed a robust linear correlation between whole-brain size and ALFF. Moreover, specific brain lobes/regions, including the frontal lobe, the left middle frontal gyrus, anterior cingulate gyrus, Rolandic operculum, and insula, also showed a reliable, positive volume-ALFF correlation in the two cohorts. These findings offer direct, empirical evidence of a strong association between brain size/volume and intrinsic brain activity, as well as provide novel insight into the structural substrates of the intrinsic brain activity of the human brain. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. ORGANIZATION AS A MANAGEMENT FUNCTION IN THE ACTIVITY OF TRADE COMPANIES

    Directory of Open Access Journals (Sweden)

    Bretan Florin-Ioan

    2013-01-01

    Full Text Available Organizational system is a set of methods, procedures and techniques used in the management of organization function of the production process. It has as main functions methodological and logistical support creation of the functional act. Generally, systems, methods and management functions trigger the assembly of the developed activities by the managed system in order to establish and achieve the aims of commercial enterprises. In most cases, the management is done by exercising a range of functions including the organization of enterprises in Maramures County, Romania.

  18. Sexual activity and function after surgical treatment in patients with (pre)invasive vulvar lesions

    NARCIS (Netherlands)

    Grimm, Donata; Eulenburg, Christine; Brummer, Oliver; Schliedermann, Anna-Katharina; Trillsch, Fabian; Prieske, Katharina; Gieseking, Friederike; Selka, Enzia; Mahner, Sven; Woelber, Linn

    Sexual activity (SA) and sexual function (SF) are central outcome measures in women affected by preinvasive (vulvar intraepithelial neoplasia, VIN) and invasive (vulvar cancer, VC) vulvar lesions. Data on sexuality after treatment are scarce. Validated questionnaires including the female sexual

  19. Chronic regulation of colonic epithelial secretory function by activation of G protein-coupled receptors.

    LENUS (Irish Health Repository)

    Toumi, F

    2011-02-01

    Enteric neurotransmitters that act at G protein-coupled receptors (GPCRs) are well known to acutely promote epithelial Cl(-) and fluid secretion. Here we examined if acute GPCR activation might have more long-term consequences for epithelial secretory function.

  20. Children with profound intellectual and multiple disabilities : the effects of functional movement activities

    NARCIS (Netherlands)

    van der Putten, A; Vlaskamp, C; Reynders, K; Nakken, H

    Objective: To determine the effect of functional movement activities within the MOVE ( Mobility Opportunities Via Education) curriculum on the independence of children with profound intellectual and multiple disabilities. Subjects: Forty-four children with profound intellectual and multiple

  1. Cortical activity in the left and right hemispheres during language-related brain functions

    DEFF Research Database (Denmark)

    Lassen, N A; Larsen, B

    1980-01-01

    of cortical activity seen during various language functions, emphasizing the practically symmetrical involvement in both hemispheres. A case of auditive agnosia (with complete cortical word deafness but preserved pure tone thresholds) is presented. The patient's normal speech constitutes evidence...

  2. Are a healthy diet and physical activity synergistically associated with cognitive functioning in older adults?

    NARCIS (Netherlands)

    Nijholt, W.; Jager-Wittenaar, H.; Visser, M.; Van der Schans, C. P.; Hobbelen, J. S. M.

    Previous research has demonstrated that being both physically active and adhering a healthy diet is associated with improved cognitive functioning; however, it remains unclear whether these factors act synergistically. We investigated the synergistic association of a healthy diet and being

  3. Evaluation of the functional activity of activated sludge from local waste water treatment plant in the Arctic region

    Directory of Open Access Journals (Sweden)

    Il'inskiy V. V.

    2017-03-01

    Full Text Available The paper considers characteristics of the activated sludge in the local wastewater treatment plant (LWTP and its ability to purify fully domestic sewage water in the Far North. Biochemical process of destruction of organic pollutants is influenced by a microbial complex functioning in aeration tanks. Taking into account climatic conditions of the region where the organic matter degradation processes are slowed, and lack of control over the operation, efficiency and occupational safety of LWTPs, it seems to be important to study the physiological characteristics of the bacteria used in bioremediation, and their ability to maximize the purifying domestic sewage in the Arctic region. Undue intervention in the biosphere systems leads to disruption of the balance of internal and external ecosystems communications. The goal of research is studying structural determination and functioning of activated sludge bacteriocenosis of LWTP TOPAS-5 (GK "Topol-ECO" in certain physical and chemical conditions of the habitat, and establishing completeness of cleaning process in this treatment plant. The paper considers the structure (quantitative and qualitative composition and function of LWTP activated sludge bacteriocenosis functioning in the Arctic region. The estimation of the activated sludge of full waste water treatment process of the LWTP has been given. The research's results have allowed to identify and determine the bacterial count of physiological groups of microorganisms purified domestic sewage; to isolate from activated sludge the bioflocculant-producing microorganisms' on the experimental medium; to evaluate efficiency of LWTP work in the Arctic region

  4. Altered sensorimotor activation patterns in idiopathic dystonia-an activation likelihood estimation meta-analysis of functional brain imaging studies

    DEFF Research Database (Denmark)

    Løkkegaard, Annemette; Herz, Damian M; Haagensen, Brian Numelin

    2016-01-01

    Dystonia is characterized by sustained or intermittent muscle contractions causing abnormal, often repetitive, movements or postures. Functional neuroimaging studies have yielded abnormal task-related sensorimotor activation in dystonia, but the results appear to be rather variable across studies....... Further, study size was usually small including different types of dystonia. Here we performed an activation likelihood estimation (ALE) meta-analysis of functional neuroimaging studies in patients with primary dystonia to test for convergence of dystonia-related alterations in task-related activity...... postcentral gyrus, right superior temporal gyrus and dorsal midbrain. Apart from the midbrain cluster, all between-group differences in task-related activity were retrieved in a sub-analysis including only the 14 studies on patients with focal dystonia. For focal dystonia, an additional cluster of increased...

  5. Preference as a Function of Active Interresponse Times: A Test of the Active Time Model

    Science.gov (United States)

    Misak, Paul; Cleaveland, J. Mark

    2011-01-01

    In this article, we describe a test of the active time model for concurrent variable interval (VI) choice. The active time model (ATM) suggests that the time since the most recent response is one of the variables controlling choice in concurrent VI VI schedules of reinforcement. In our experiment, pigeons were trained in a multiple concurrent…

  6. Muscle activity during functional coordination training: implications for strength gain and rehabilitation.

    Science.gov (United States)

    Jørgensen, Marie B; Andersen, Lars L; Kirk, Niels; Pedersen, Mogens T; Søgaard, Karen; Holtermann, Andreas

    2010-07-01

    The purpose of this study was to evaluate if different types, body positions, and levels of progression of functional coordination exercises can provide sufficiently high levels of muscle activity to improve strength of the neck, shoulder, and trunk muscles. Nine untrained women were familiarized with 7 functional coordination exercises 12 times during 4 weeks before testing. Surface electromyographic (EMG) activity was obtained from rectus abdominus, erector spinae, obliquus externus, and trapezius during the exercises with 2-4 levels of progression. Electromyography was normalized to the maximal EMG activity during maximal voluntary contractions, and a p value muscles reached sufficiently high levels of activity during the coordination exercises for strength gain (>60% of maximal EMG activity). Type of exercise played a significant role for the attained muscle activity. Body position during the exercises was important for the activity of the erector spinae, and level of progression was important for the activity of the trapezius. The findings indicate that depending on type, body position, and level of progression, functional coordination training can be performed with a muscle activity sufficient for strength gain. Functional coordination training may therefore be a good choice for prevention or rehabilitation of musculoskeletal pain or injury in the neck, shoulder, or trunk muscles.

  7. Physical activity and obesity mediate the association between childhood motor function and adolescents' academic achievement.

    Science.gov (United States)

    Kantomaa, Marko T; Stamatakis, Emmanuel; Kankaanpää, Anna; Kaakinen, Marika; Rodriguez, Alina; Taanila, Anja; Ahonen, Timo; Järvelin, Marjo-Riitta; Tammelin, Tuija

    2013-01-29

    The global epidemic of obesity and physical inactivity may have detrimental implications for young people's cognitive function and academic achievement. This prospective study investigated whether childhood motor function predicts later academic achievement via physical activity, fitness, and obesity. The study sample included 8,061 children from the Northern Finland Birth Cohort 1986, which contains data about parent-reported motor function at age 8 y and self-reported physical activity, predicted cardiorespiratory fitness (cycle ergometer test), obesity (body weight and height), and academic achievement (grades) at age 16 y. Structural equation models with unstandardized (B) and standardized (β) coefficients were used to test whether, and to what extent, physical activity, cardiorespiratory fitness, and obesity at age 16 mediated the association between childhood motor function and adolescents' academic achievement. Physical activity was associated with a higher grade-point average, and obesity was associated with a lower grade-point average in adolescence. Furthermore, compromised motor function in childhood had a negative indirect effect on adolescents' academic achievement via physical inactivity (B = -0.023, 95% confidence interval = -0.031, -0.015) and obesity (B = -0.025, 95% confidence interval = -0.039, -0.011), but not via cardiorespiratory fitness. These results suggest that physical activity and obesity may mediate the association between childhood motor function and adolescents' academic achievement. Compromised motor function in childhood may represent an important factor driving the effects of obesity and physical inactivity on academic underachievement.

  8. Physical activity and obesity mediate the association between childhood motor function and adolescents’ academic achievement

    Science.gov (United States)

    Kantomaa, Marko T.; Stamatakis, Emmanuel; Kankaanpää, Anna; Kaakinen, Marika; Rodriguez, Alina; Taanila, Anja; Ahonen, Timo; Järvelin, Marjo-Riitta; Tammelin, Tuija

    2013-01-01

    The global epidemic of obesity and physical inactivity may have detrimental implications for young people’s cognitive function and academic achievement. This prospective study investigated whether childhood motor function predicts later academic achievement via physical activity, fitness, and obesity. The study sample included 8,061 children from the Northern Finland Birth Cohort 1986, which contains data about parent-reported motor function at age 8 y and self-reported physical activity, predicted cardiorespiratory fitness (cycle ergometer test), obesity (body weight and height), and academic achievement (grades) at age 16 y. Structural equation models with unstandardized (B) and standardized (β) coefficients were used to test whether, and to what extent, physical activity, cardiorespiratory fitness, and obesity at age 16 mediated the association between childhood motor function and adolescents’ academic achievement. Physical activity was associated with a higher grade-point average, and obesity was associated with a lower grade-point average in adolescence. Furthermore, compromised motor function in childhood had a negative indirect effect on adolescents’ academic achievement via physical inactivity (B = –0.023, 95% confidence interval = –0.031, –0.015) and obesity (B = –0.025, 95% confidence interval = –0.039, –0.011), but not via cardiorespiratory fitness. These results suggest that physical activity and obesity may mediate the association between childhood motor function and adolescents’ academic achievement. Compromised motor function in childhood may represent an important factor driving the effects of obesity and physical inactivity on academic underachievement. PMID:23277558

  9. Lifelong physical activity preserves functional sympatholysis and purinergic signalling in the ageing human leg

    DEFF Research Database (Denmark)

    Mortensen, S P; Nyberg, Michael; Winding, K

    2012-01-01

    and exercise hyperaemia in the leg and whether ATP signalling is altered by ageing and physical activity. Leg haemodynamics, interstitial [ATP] and P2Y(2) receptor content was determined in eight young (23 ± 1 years), eight lifelong sedentary elderly (66 ± 2 years) and eight lifelong active elderly (62 ± 2...... not alter the vasodilator response to ATP infusion in any of the three groups. Plasma [noradrenaline] increased more during tyramine infusion in both elderly groups compared to young (P physically active lifestyle can maintain an intact functional sympatholysis during exercise......Ageing is associated with an impaired ability to modulate sympathetic vasoconstrictor activity (functional sympatholysis) and a reduced exercise hyperaemia. The purpose of this study was to investigate whether a physically active lifestyle can offset the impaired functional sympatholysis...

  10. Functions of Cross-Border Economic Activities in Skouw Sae Community, Jayapura City

    Directory of Open Access Journals (Sweden)

    La Usman

    2017-06-01

    Full Text Available Cross-border economic activities are often done by people of Skouw Sae Village, Muara Tami District, Jayapura City to Wutung Village, Vanimo, Papua New Guinea. This study attempts to analyze the functions of economic activity in this community. Data were processed using qualitative analysis. The results of this study found seven functions of cross-border economic activities. First, to meet nutritional needs of the family. Second, to meet reproductive needs for family continuity. Third, to meet the needs for comfort and welfare of wife's family. Fourth, to meet safety needs. Fifth, to meet the needs for relaxation. Sixth, to meet mobility needs. Seventh, to meet the needs for growth. It also meets the needs for activities and systems of ideas related to the fulfillment of seven needs. In conclusion, the functions of cross-border economic activities of Skouw Sae Village are to meet basic, institutional and symbolical needs of local people.

  11. Muscle activity during functional coordination training: implications for strength gain and rehabilitation

    DEFF Research Database (Denmark)

    Jørgensen, Marie Birk; Andersen, Lars Louis; Kirk, Niels

    2010-01-01

    The purpose of this study was to evaluate if different types, body positions, and levels of progression of functional coordination exercises can provide sufficiently high levels of muscle activity to improve strength of the neck, shoulder, and trunk muscles. Nine untrained women were familiarized...... for the attained muscle activity. Body position during the exercises was important for the activity of the erector spinae, and level of progression was important for the activity of the trapezius. The findings indicate that depending on type, body position, and level of progression, functional coordination...... training can be performed with a muscle activity sufficient for strength gain. Functional coordination training may therefore be a good choice for prevention or rehabilitation of musculoskeletal pain or injury in the neck, shoulder, or trunk muscles....

  12. Task-free presurgical mapping using functional magnetic resonance imaging intrinsic activity.

    Science.gov (United States)

    Liu, Hesheng; Buckner, Randy L; Talukdar, Tanveer; Tanaka, Naoaki; Madsen, Joseph R; Stufflebeam, Steven M

    2009-10-01

    Low-frequency components of the spontaneous functional MR imaging signal provide information about the intrinsic functional and anatomical organization of the brain. The ability to use such methods in individual patients may provide a powerful tool for presurgical planning. The authors explore the feasibility of presurgical motor function mapping in which a task-free paradigm is used. Six surgical candidates with tumors or epileptic foci near the motor cortex participated in this study. The investigators directly compared task-elicited activation of the motor system to activation obtained from intrinsic activity correlations. The motor network within the unhealthy hemisphere was identified based on intrinsic activity correlations, allowing distortions of functional anatomy caused by the tumor and epilepsy to be directly visualized. The precision of the motor function mapping was further explored in 1 participant by using direct cortical stimulation. The motor regions localized based on the spontaneous activity correlations were quite similar to the regions defined by actual movement tasks and cortical stimulation. Using intrinsic activity correlations, it was possible to map the motor cortex in presurgical patients. This task-free paradigm may provide a powerful approach to map functional anatomy in patients without task compliance and allow multiple brain systems to be determined in a single scanning session.

  13. The Geriatric Hand: Correlation of Hand-Muscle Function and Activity Restriction in Elderly

    Science.gov (United States)

    Incel, Nurgul Arinci; Sezgin, Melek; As, Ismet; Cimen, Ozlem Bolgen; Sahin, Gunsah

    2009-01-01

    On the basis of the importance of hand manipulation in activities of daily living (ADL), deterioration of hand function because of various factors reduces quality and independence of life of the geriatric population. The aim of this study was to identify age-induced changes in manual function and to quantify the correlations between hand-muscle…

  14. Pharmacological aspects of corticotrophinergic and vasopressinergic function tests for HPA axis activation

    NARCIS (Netherlands)

    Jacobs, Gabriël Etienne

    2010-01-01

    This thesis focuses on the quantification of hypothalamus-pituitary-adrenal (HPA) axis activation in healthy volunteers by applying pharmacological function tests with distinct pharmacodynamic (PD) mechanisms. Its main objective is to contribute to the validation of different function tests for the

  15. Differential effect of spinal cord injury and functional impairment on human brain activation

    NARCIS (Netherlands)

    Curt, A; Bruehlmeier, M; Leenders, KL; Roelcke, U; Dietz, [No Value

    Reorganization of human brain function after spinal cord injury (SCI) has been shown in electrophysiological studies. However, it is less clear how far changes of brain activation in SCI patients are influenced by the extent of SCI (neuronal lesion) or the consequent functional impairment. Positron

  16. Cross-sectional imaging of functional activation in the rat somatosensory cortex with optical coherence tomography

    Science.gov (United States)

    Aguirre, A. D.; Chen, Y.; Ruvinskaya, L.; Devor, A.; Boas, D. A.; Fujimoto, J. G.

    2005-08-01

    Simultaneous optical coherence tomography (OCT) and video microscopy were performed on the rat somatosensory cortex through a thinned skull during forepaw stimulation. Fractional change measurements in OCT images reveal a functional signal timecourse similar to well understood hemodynamic signal timecourses measured with video microscopy. The precise etiology of the observed OCT functional signal is still under investigation, but these results suggest that OCT can provide high-resolution cross-sectional images of functional neuro-vascular activation.

  17. Understanding the Functionality of Human Activity Hotspots from Their Scaling Pattern Using Trajectory Data

    Directory of Open Access Journals (Sweden)

    Tao Jia

    2017-11-01

    Full Text Available Human activity hotspots are the clusters of activity locations in space and time, and a better understanding of their functionality would be useful for urban land use planning and transportation. In this article, using trajectory data, we aim to infer the functionality of human activity hotspots from their scaling pattern in a reliable way. Specifically, a large number of stopping locations are extracted from trajectory data, which are then aggregated into activity hotspots. Activity hotspots are found to display scaling patterns in terms of the sublinear scaling relationships between the number of stopping locations and the number of points of interest (POIs, which indicates economies of scale of human interactions with urban land use. Importantly, this scaling pattern remains stable over time. This finding inspires us to devise an allometric ruler to identify the activity hotspots, whose functionality could be reliably estimated using the stopping locations. Thereafter, a novel Bayesian inference model is proposed to infer their urban functionality, which examines the spatial and temporal information of stopping locations covering 75 days. Experimental results suggest that the functionality of identified activity hotspots are reliably inferred by stopping locations, such as the railway station.

  18. An investigation of the functional groups on the surface of activated carbons

    Directory of Open Access Journals (Sweden)

    MARYTE DERVINYTE

    2004-05-01

    Full Text Available Activated carbons were produced in the laboratory from wood using a 20-run Plackett–Burman experimental design for 19 factors. The obtained batches of activated carbon were analysed by potentiometric titration and FTIR spectroscopy to determine the surface functional groups. The results obtained by potentiometric titration displayed the distribution of individual acidity constants of those groups in the pK range. Considering this parameter, the surface functional groups were divided into carboxyl, lactone and phenol. The linear regression equations reflecting the influence of each operation used for the synthesis on the amount of these functional groups in the obtained activated carbons were generated. The FTIR spectra were used in parallel for the evaluation of the amount and the type of the surface functional groups. Relationships between the two data sets obtained by potentiometric titration and FTIR spectroscopy were evaluated by correlation analysis. It was established that the amount of surface functional groups determined by potentiometric titration positively correlates with the intensity of the peaks of hydrophilic functional groups in the FTIR spectra. At the same time, the negative correlation between potentiometrically determined amount of surface functional groups and the intensity of peaks of hydrophobic functional groups was observed. Most probably, these non-polar formations can take part in the interaction of carbon surface with H+/OH- ions and diminish the strength of existent functional groups.

  19. Physical activity and trajectories in cognitive function: English Longitudinal Study of Ageing.

    Science.gov (United States)

    Hamer, Mark; Muniz Terrera, Graciela; Demakakos, Panayotes

    2018-02-06

    There are limited data on physical activity in relation to trajectories in cognitive function. The aim was to examine the association of physical activity with trajectories in cognitive function, measured from repeated assessments over 10 years. We conducted a 10-year follow-up of 10 652 (aged 65±10.1 years) men and women from the English Longitudinal Study of Ageing, a cohort of community dwelling older adults. Self-reported physical activity was assessed at baseline and neuropsychological tests of memory and executive function were administered at regular 2-year intervals. Data from six repeated measurements of memory over 10 years and five repeated measurements of executive function over 8 years were used. The multivariable models revealed relatively small baseline differences in cognitive function by physical activity status in both men and women. Over the 10-year follow-up, physically inactive women experienced a greater decline in their memory (-0.20 recalled words, 95% CI -0.29 to -0.11, per study wave) and in executive function ability (-0.33 named animals; -0.54 to -0.13, per study wave) in comparison with the vigorously active reference group. In men, there were no differences in memory (-0.08 recalled words, 95% CI -0.18 to 0.01, per study wave), but small differences in executive function (-0.23 named animals; -0.46 to -0.01, per study wave) between inactive and vigorously active. Physical activity was associated with preservation of memory and executive function over 10 years follow-up. The results were, however, more pronounced in women. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  20. Cerebral activation during Chinese semantic associative task in Xinjiang' Uyghurs: a functional MRI study

    International Nuclear Information System (INIS)

    Yang Lixia; Jia Wenxiao; Tang Weijun; Wang Hong; Ding Shuang; Wang Hao

    2010-01-01

    Objective: To explore the cerebral activation in Xinjiang' Uyghurs when performing a Chinese word tasks by the functional magnetic resonance image (fMRI). Methods: Twenty-one healthy Xinjiang' Uyghurs and 11 healthy Hans were scanned using functional magnetic resonance imaging (fMRI) on a 1.5 T MRI scanner with a single run. Different Chinese words were displayed in each block to avoid any practice effect. SPM5.0 software was used for image data processing. To evaluate the inter subject consistency of brain activations associated with Chinese character and word reading, we created penetrance maps by combining binary individual functional maps. Results: For Uyghur-Chinese bilingual subjects, activations related to generated a word that was semantically related to each stimulus. The results indicated that reading Chinese is characterized by extensive activity of the neural systems. Peak activations occurred in the left middle frontal cortex at Brodmann Areas (BA9 and BA47). The left temporal (BA37) cortices were also strongly activated. Other important activated areas included bilateral visual systems (BA17-19) and cerebellum. The location of peak activation in the left frontal regions was similar in Native Uyghurs and Hans. But the active areas in Uyghurs are more extensive than that of Hans. Conclusions: The location of peak activation in the left frontal regions was similar in Native Uyghurs and Hans. More brain areas were needed for Xinjiang' Uyghur speakers during processing Chinese words. (authors)

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

    Science.gov (United States)

    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...

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

    Science.gov (United States)

    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...

  3. Enhancing Preschoolers' Executive Functions through Embedding Cognitive Activities in Shared Book Reading

    Science.gov (United States)

    Howard, S. J.; Powell, T.; Vasseleu, E.; Johnstone, S.; Melhuish, E.

    2017-01-01

    Given evidence that early executive functioning sets the stage for a broad range of subsequent outcomes, researchers have sought to identify ways to foster these cognitive capacities. The current series of studies sought to design, develop, and provide evidence for the efficacy of embedding cognitive activities in a commonplace activity--shared…

  4. Targeting complement activation in brain-dead donors improves renal function after transplantation

    NARCIS (Netherlands)

    Damman, Jeffrey; Hoeger, Simone; Boneschansker, Leo; Theruvath, Ashok; Waldherr, Ruediger; Leuvenink, Henri G.; Ploeg, Rutger J.; Yard, Benito A.; Seelen, Marc A.

    Kidneys recovered from brain-dead donors have inferior outcomes after transplantation compared to kidneys from living donors. Since complement activation plays an important role in renal transplant related injury, targeting complement activation in brain-dead donors might improve renal function

  5. Strength and voluntary activation in relation to functioning in patients with osteoarthritis.

    NARCIS (Netherlands)

    Dr. D.M. van Leeuwen

    2013-01-01

    Osteoarthritis (OA) is characterized by pain, and problems with activities of daily life, especially if the hip or knee joint is affected. The aim of this project was to study associations between strength, voluntary activation and physical functioning in elderly patients with OA. People with OA of

  6. Active life in old age. Combining measures of functional ability and social participation

    DEFF Research Database (Denmark)

    Avlund, K; Holstein, B E; Mortensen, Erik Lykke

    1999-01-01

    This paper describes a new measure of Active Life Expectancy, called Active Life Classification (ALC) in which the criterion for successful aging is a combination of good functional ability and high social participation. OBJECTIVES: 1) to describe the distribution of ALC among 75-year-old men...... were associated with ALC. CONCLUSIONS: It is an advantage to combine functional ability and social participation in the description of quality of life in old age, as 1) a high social participation may compensate for a poor functional ability, and vice versa, 2) the combined measure is meaningful...... for both sexes, and 3) it gives more information than the two concepts used as separate outcome measures....

  7. Functional Specificity of the Visual Word Form Area: General Activation for Words and Symbols but Specific Network Activation for Words

    Science.gov (United States)

    Reinke, Karen; Fernandes, Myra; Schwindt, Graeme; O'Craven, Kathleen; Grady, Cheryl L.

    2008-01-01

    The functional specificity of the brain region known as the Visual Word Form Area (VWFA) was examined using fMRI. We explored whether this area serves a general role in processing symbolic stimuli, rather than being selective for the processing of words. Brain activity was measured during a visual 1-back task to English words, meaningful symbols…

  8. [On mechanism of functional changes in the organism of teenagers at different levels of locomotor activity].

    Science.gov (United States)

    Mindubaeva, F A; Shukurov, F A; Salikhova, Y Y; Niyazova, Y I; Ramazanov, A K

    2015-02-01

    Comprehensive study of the cardiovascular system functional condition of 15-16 teenagers while in normal daily locomotor activity and in the mode of regular moderate physical activity was performed. The features of cerebral circulation and myocardium functional condition of teenagers are studied depending on initial tonus of the autonomic nervous system and locomotor activity level in the process of continuous step physical activity on tredmil. The condition of regulatory mechanisms, providing adaptation of teenagers in the conditions of modern school was studied. Research results showed, that elasticity of cerebrum arterial vessels, veins tone, venous outflow for teenagers not having regular physical activity, considerably mionectic. More adequate reaction of coronary blood flow in the process of physical activity is educed for the trained teenagers with the balanced autonomic regulation of cardiac rhythm. This group showed a higher level and regulation quality of organism reserve possibilities.

  9. Physical and Cognitive Functions, Physical Activity, and Sedentary Behavior in Older Adults With Multiple Sclerosis.

    Science.gov (United States)

    Bollaert, Rachel E; Motl, Robert W

    2017-12-01

    Older adults with multiple sclerosis (MS) experience age-related declines in physical and cognitive functions that may be compounded by the disease and its progression and worsened by physical inactivity and sedentary behavior. However, the extent to which impairments in physical and cognitive functions are manifestations of MS and disease progression, reflective of the general aging process, or perhaps 2 detrimental processes exacerbating the synergistic effects of the other is relatively unknown. This study compared physical and cognitive functions, sedentary behavior, and physical activity between 40 older adults with MS (ie, 60 years of age and older) and 40 age- and sex-matched healthy older adults. We further examined whether physical activity and/or sedentary behavior explained differences between groups in physical and cognitive functions. Participants initially underwent the cognitive assessments, followed by the physical function assessments. The order of tests was standardized and participants were provided seated-rest between the administrations of the physical function assessments. Participants were then instructed to wear an accelerometer and document wear time in a log book for a 7-day period after the testing session. Multivariate analyses of variance indicated that older adults with MS (n = 40) performed worse on all measures of physical function, and 1 measure of cognitive function (ie, information-processing speed), compared with healthy controls (n = 40). Older adults with MS engaged in less moderate-to-vigorous physical activity, more sedentary behavior, and longer duration of long sedentary bouts than healthy controls. Pearson correlations demonstrated that levels and patterns of physical activity were significantly associated with a majority of physical function variables but not cognitive function variables in both older adults with MS and healthy controls but to a greater extent in older adults with MS. Partial Pearson correlations further

  10. Evaluation of Na+/K+ pump function following repetitive activity in mouse peripheral nerve

    DEFF Research Database (Denmark)

    Moldovan, Mihai; Krarup, Christian

    2006-01-01

    After conduction of prolonged trains of impulses the increased Na+/K+ pump activity leads to hyperpolarization. The aim of this study was to develop a mouse model to investigate the Na+/K+ pump function in peripheral nerve by measuring the decrease in excitability during activity...... change after repetitive stimulation of the mouse tibial nerve is an indicator of the Na+/K+ pump function in vivo. Evaluation of activity-dependent hyperpolarization may be an important indicator of axonal ability to cope with Na+ load....

  11. The Contribution of Generative Leisure Activities to Cognitive Function among Sri Lankan Elderly

    Science.gov (United States)

    Maselko, Joanna; Sebranek, Matthew; Mun, Mirna Hodzic; Perera, Bilesha; Ahs, Jill; Østbye, Truls

    2014-01-01

    OBJECTIVES Although a substantive body of research has shown a protective association between leisure activities and cognitive function, consistent evidence is lacking about which specific types of activities should be promoted. The objective of this analysis was to examine the unique contribution of generative leisure activities, defined as activities motivated by “a concern for others and a need to contribute something to the next generation” (Erikson). DESIGN Cross-sectional survey. SETTING Peri-urban and rural area in southern Sri Lanka. PARTICIPANTS Community dwelling adults aged 60+ (n=252). MEASUREMENTS Main predictors were leisure activities grouped into generative, social, or solitary. Main outcome was cognitive function assessed with Montreal Cognitive Assessment (MoCA) and the Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE). RESULTS We found that more frequent engagement in generative leisure activities was associated with higher levels of cognitive function, independent of the impact of other social and solitary leisure activities. In a fully adjusted model combining all three leisure activities, generative activities independently predicted cognitive function as measured with the MoCA (β =0.47 (0.11 to 0.83) and the IQCODE (β = -0.81 (-1.54 to -0.09)). In this combined model, solitary activities were also independently associated with slower cognitive decline with the MoCA (β =0.40 (0.16, 0.64), but not with IQCODE (β =-0.38 (-0.88, 0.12)); the association with social activities did not reach statistical significance with either measure. These associations did not differ meaningfully by gender. CONCLUSION Generative leisure activities are a promising area for the development of interventions aimed at reducing cognitive decline among the elderly. PMID:25139145

  12. SANS-polymer and functional materials with neutron in Indonesia. Progress report on the collaboration activities?

    International Nuclear Information System (INIS)

    Ikram, A.; Gunawan; Sukirman, E.; Ridwan; Jahja, A.K.

    2000-01-01

    Activities on SANS-polymer collaboration program are reported. This paper presents SANS-data from Sodium Dodecyl Sulphate that have been obtained using BATAN's SANS machine in Serpong. Reports are also presented about activities in the groups for functional materials structural determination which includes magnetic, HTc superconducting and superionic conducting materials. Discussions are also given towards the way the collaboration activities were carried out in the last three years as well as impact of neutron scattering facility conditions in Indonesia. (author)

  13. A review of the effects of physical activity and sports concussion on brain function and anatomy.

    Science.gov (United States)

    Tremblay, Sara; Pascual-Leone, Alvaro; Théoret, Hugo

    2017-09-08

    Physical activity has been associated with widespread anatomical and functional brain changes that occur following acute exercise or, in the case of athletes, throughout life. High levels of physical activity through the practice of sports also lead to better general health and increased cognitive function. Athletes are at risk, however, of suffering a concussion, the effects of which have been extensively described for brain function and anatomy. The level to which these effects are modulated by increased levels of fitness is not known. Here, we review literature describing the effects of physical activity and sports concussions on white matter, grey matter, neurochemistry and cortical excitability. We suggest that the effects of sports concussion can be coufounded by the effects of exercise. Indeed, available data show that the brain of athletes is different from that of healthy individuals with a non-active lifestyle. As a result, sports concussions take place in a context where structural/functional plasticity has occurred prior to the concussive event. The sports concussion literature does not permit, at present, to separate the effects of intense and repeated physical activity, and the abrupt removal from such activities, from those of concussion on brain structure and function. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. [Study on mechanism of eustachian tube active opening ventilation and pump-like function].

    Science.gov (United States)

    Zhang, X; Huang, X

    1994-01-01

    A modified methods for assessing the eustachian tube function (ETF) in patients with traumatic tympanic membrane perforation and otitis media were developed by using a custom-designed ETF measuring instrument. These methods consist of dynamic flow swallow test (DFST), positive pressure swallow test (PST), negative pressure swallow test (NST) and micro-negative pressure swallow test (MNST). With these methods, the graphs and parameters presenting ET active opening function were obtained. The results suggested that the ET active swallow opening is a rather complex process of biomechanical action. It is not only closely related to the function of middle ear ventilation but also related to pump-like function and the protective function against reflux infection from nasopharynx.

  15. Upper and lower limb functionality and body mass index in physically active older adults

    Directory of Open Access Journals (Sweden)

    Juliana Molinari Tecchio

    Full Text Available Abstract Introduction: Aging leads to sarcopenia and functional capacity decline, compromising upper (UL and lower limb (LL performance of activities. Body mass index (BMI is an important parameter for the assessment of health conditions in older adults, especially with regard to obesity, since it leads to functional limitations in terms of mobility and task performance. Objective: To investigate the potential association between UL and LL functionality and BMI in physically active older adults; and to characterize this population with regard to BMI and UL and LL functionality. Methods: The data were collected between August 2013 and April 2014. The sample comprised 371 physically active older adults. This study used secondary data from the program “PET Saúde IPA/SMS”. The program interviewed older adults living in areas comprised by the Third Family Health Unit of a neighborhood in Porto Alegre/RS. This paper used questions from the “Instrumento de Avaliação Multidimensional Rápida da Pessoa Idosa” (Instrument for Rapid Multidimensional Assessment of Elderly People, in English that had to do with UL and LL functionality, weight, height and BMI. Results and Conclusion: There was no association between UL and LL functionality and BMI in physically active older adults. More than half of the sample was overweight. Most participants had functional UL and LL. While occupation, self-perception of health as “good” and “very good”, and physical activity were found to be associated with LL functionality; regular physical exercise was found to be associated with UL and LL functionality.

  16. Mass Functions of the Active Black Holes in Distant Quasars from the Sloan Digital Sky Survey Data Release 3

    DEFF Research Database (Denmark)

    Vestergaard, Marianne; Fan, X.; Tremonti, C. A.

    2007-01-01

    We present the mass functions of actively accreting supermassive black holes over the redshift range 0.3......We present the mass functions of actively accreting supermassive black holes over the redshift range 0.3...

  17. Acute Cognitively Engaging Exergame-Based Physical Activity Enhances Executive Functions in Adolescents

    Science.gov (United States)

    Heinks, Theda; Eggenberger, Noëmi; Schmidt, Mirko

    2016-01-01

    The study aimed to elucidate the influence of cognitive engagement comprised in an acute bout of exergame-based physical activity on executive functions (inhibition, cognitive flexibility) in adolescents. Therefore, the level of cognitive engagement and the intensity of physical activity were systematically varied across three experimental conditions. Sixty-five healthy male adolescents (13–16 years) were randomly assigned to one of three conditions: (a) physical activity with high levels of cognitive engagement during active video gaming, (b) physical activity with low levels of cognitive engagement during active video gaming, (c) sedentary with low levels of cognitive engagement during passive video watching. Manipulation checks, including subjective and objective operationalizations of cognitive engagement, were applied. Executive functions were assessed before and after each condition using the D-KEFS design fluency test. Results showed that cognitive engagement, operationalized by subjects’ ratings and heart rate variability, differed between conditions. The physical activity condition with a high level of cognitive engagement resulted in significantly better performance in cognitive flexibility compared to conditions with low levels of cognitive engagement. Regarding benefits for executive functions in male adolescents, the results indicate that acute physical activity with high cognitive engagement could be more efficient than physical activity of the same intensity with low cognitive engagement. Even though further evidence is needed, these results extend previous research and suggest a methodological approach for measuring cognitive engagement. PMID:28030542

  18. How to Make an Active Zone: Unexpected Universal Functional Redundancy between RIMs and RIM-BPs.

    Science.gov (United States)

    Acuna, Claudio; Liu, Xinran; Südhof, Thomas C

    2016-08-17

    RIMs and RIM-binding proteins (RBPs) are evolutionary conserved multidomain proteins of presynaptic active zones that are known to recruit Ca(2+) channels; in addition, RIMs perform well-recognized functions in tethering and priming synaptic vesicles for exocytosis. However, deletions of RIMs or RBPs in mice cause only partial impairments in various active zone functions and have no effect on active zone structure, as visualized by electron micrographs, suggesting that their contribution to active zone functions is limited. Here, we show in synapses of the calyx of Held in vivo and hippocampal neurons in culture that combined, but not individual, deletions of RIMs and RBPs eliminate tethering and priming of synaptic vesicles, deplete presynaptic Ca(2+) channels, and ablate active zone complexes, as analyzed by electron microscopy of chemically fixed synapses. Thus, RBPs perform unexpectedly broad roles at the active zone that together with those of RIMs are essential for all active zone functions. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. [Active aging from the perspective of aged individuals who are functionally independent].

    Science.gov (United States)

    Ferreira, Olivia Galvão Lucena; Maciel, Silvana Carneiro; Silva, Antonia Oliveira; dos Santos, Walberto Silva; Moreira, Maria Adelaide Silva P

    2010-12-01

    The objective of this study was to identify the social representations of the elderly regarding active aging. Semi-structured interviews were performed with 100 functionally independent aged individuals from João Pessoa, Paraiba, Brazil. The data was organized and analyzed using Alceste software. Results showed that the aged individuals' statements about active aging are permeated with positive contents. However, when aging is not associated with the word active, it is still represented as losses and disabilities. Despite the existence of losses during the process, active aging should be encouraged among the elderly, as it means living a quality, plentiful life. Maintaining the elderly functionally independent is the first step to achieving active aging and thus improving their quality of life.

  20. Detection of cortical activities on eye movement using functional magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Yoshida, Masaki; Kawai, Kazushige; Kitahara, Kenji [Jikei Univ., Tokyo (Japan). School of Medicine; Soulie, D.; Cordoliani, Y.S.; Iba-Zizen, M.T.; Cabanis, E.A.

    1997-11-01

    Cortical activity during eye movement was examined with functional magnetic resonance imaging. Horizontal saccadic eye movements and smooth pursuit eye movements were elicited in normal subjects. Activity in the frontal eye field was found during both saccadic and smooth pursuit eye movements at the posterior margin of the middle frontal gyrus and in parts of the precentral sulcus and precentral gyrus bordering the middle frontal gyrus (Brodmann`s areas 8, 6, and 9). In addition, activity in the parietal eye field was found in the deep, upper margin of the angular gyrus and of the supramarginal gyrus (Brodmann`s areas 39 and 40) during saccadic eye movement. Activity of V5 was found at the intersection of the ascending limb of the inferior temporal sulcus and the lateral occipital sulcus during smooth pursuit eye movement. Our results suggest that functional magnetic resonance imaging is useful for detecting cortical activity during eye movement. (author)

  1. Detection of cortical activities on eye movement using functional magnetic resonance imaging

    International Nuclear Information System (INIS)

    Yoshida, Masaki; Kawai, Kazushige; Kitahara, Kenji; Soulie, D.; Cordoliani, Y.S.; Iba-Zizen, M.T.; Cabanis, E.A.

    1997-01-01

    Cortical activity during eye movement was examined with functional magnetic resonance imaging. Horizontal saccadic eye movements and smooth pursuit eye movements were elicited in normal subjects. Activity in the frontal eye field was found during both saccadic and smooth pursuit eye movements at the posterior margin of the middle frontal gyrus and in parts of the precentral sulcus and precentral gyrus bordering the middle frontal gyrus (Brodmann's areas 8, 6, and 9). In addition, activity in the parietal eye field was found in the deep, upper margin of the angular gyrus and of the supramarginal gyrus (Brodmann's areas 39 and 40) during saccadic eye movement. Activity of V5 was found at the intersection of the ascending limb of the inferior temporal sulcus and the lateral occipital sulcus during smooth pursuit eye movement. Our results suggest that functional magnetic resonance imaging is useful for detecting cortical activity during eye movement. (author)

  2. INVESTIGETING THE EFFECTS OF STANDING TRAINING ON BODY FUNCTIONS AND ACTIVITY FOR NONAMBULATORY CHILDREN WITH MYELOMENINGOCELE

    Directory of Open Access Journals (Sweden)

    Ozge Cankaya

    2017-09-01

    Full Text Available Background: It was indicated in many studies that verticalization have positive effects such as preventing fractures,regulating cardiopulmonary functions, increasing the head control, and the facilitation of postural muscles in pediatric patients, however, no study showing the effect of supported standing in patients with myelomeningocele on body functions and activity was encountered. The aim of this study is to examine the effects of structured supported standing training in children with myelomeningocele on body functions and activity according to ICF-CY. Methods: Twenty-five children with MMC aged between 3 and 17, who were divided into two groups-SST and control. The supported standing training was given to supported standing group 2 hours a day for 8 weeks in addition to the routine physical therapy program. Body functions were assessed with the Trunk Impairment Scale, and activity levels were assessed with the Gross Motor Function Measurement-88 and Pediatric Functional Independence Measurement at the beginning of the study, at the end of 8 weeks and at the end of 12 weeks from beginning. Results: The results of the structured supported standing training program during 8 weeks showed that children’s body functions and activity increased statistically significantly in SST group (p0.05. Conclusion: The results show that supported standing training effects the body functions and activity positively. It is recommended to educate the families for the supported standing training to be added to the routine physiotherapy and rehabilitation program for children with MMC and continue the training at home.

  3. Functions of delay-period activity in the prefrontal cortex and mnemonic scotomas revisited

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    Shintaro eFunahashi

    2015-02-01

    Full Text Available Working memory is one of key concepts to understand functions of the prefrontal cortex. Delay-period activity is an important neural correlate to understand the role of working memory in prefrontal functions. The importance of delay-period activity is that this activity can encode not only visuospatial information but also a variety of information including non-spatial visual features, auditory and tactile stimuli, task rules, expected reward, and numerical quantity. This activity also participates in a variety of information processing including sensory-to-motor information transformation. These mnemonic features of delay-period activity enable to perform various important operations that the prefrontal cortex participates in, such as executive controls, and therefore, support the notion that working memory is an important function to understand prefrontal functions. On the other hand, although experiments using manual versions of the delayed-response task had revealed many important findings, an oculomotor version of this task enabled us to use multiple cue positions, exclude postural orientation during the delay period, and further prove the importance of mnemonic functions of the prefrontal cortex. In addition, monkeys with unilateral lesions exhibited specific impairment only in the performance of memory-guided saccades directed toward visual cues in the visual field contralateral to the lesioned hemisphere. This result indicates that memories for visuospatial coordinates in each hemifield are processed primarily in the contralateral prefrontal cortex. This result further strengthened the idea of mnemonic functions of the prefrontal cortex. Thus, the mnemonic functions of the prefrontal cortex and delay-period activity may not need to be reconsidered, but should be emphasized.

  4. Functions of delay-period activity in the prefrontal cortex and mnemonic scotomas revisited.

    Science.gov (United States)

    Funahashi, Shintaro

    2015-01-01

    Working memory (WM) is one of key concepts to understand functions of the prefrontal cortex. Delay-period activity is an important neural correlate to understand the role of WM in prefrontal functions. The importance of delay-period activity is that this activity can encode not only visuospatial information but also a variety of information including non-spatial visual features, auditory and tactile stimuli, task rules, expected reward, and numerical quantity. This activity also participates in a variety of information processing including sensory-to-motor information transformation. These mnemonic features of delay-period activity enable to perform various important operations that the prefrontal cortex participates in, such as executive controls, and therefore, support the notion that WM is an important function to understand prefrontal functions. On the other hand, although experiments using manual versions of the delayed-response task had revealed many important findings, an oculomotor version of this task enabled us to use multiple cue positions, exclude postural orientation during the delay period, and further prove the importance of mnemonic functions of the prefrontal cortex. In addition, monkeys with unilateral lesions exhibited specific impairment only in the performance of memory-guided saccades directed toward visual cues in the visual field contralateral to the lesioned hemisphere. This result indicates that memories for visuospatial coordinates in each hemifield are processed primarily in the contralateral prefrontal cortex. This result further strengthened the idea of mnemonic functions of the prefrontal cortex. Thus, the mnemonic functions of the prefrontal cortex and delay-period activity may not need to be reconsidered, but should be emphasized.

  5. [Relationship between cognitive function and physical activities: a longitudinal study among community-dwelling elderly].

    Science.gov (United States)

    Konagaya, Yoko; Watanabe, Tomoyuki; Ohta, Toshiki

    2012-01-01

    The purpose of this study was to evaluate whether physical activities reduce the risk of cognitive decline in community-dwelling elderly. We investigated correlations between cognitive functions at baseline and physical activities, correlations between cognitive functions at baseline and cognitive decline over 4 years, as well as correlations between physical activity at baseline and cognitive decline over 4 years. At baseline, 2,431 community-dwelling elderly completed the cognitive screening by telephone (TICS-J), and answered the questionnaires about physical activities. Of these, 1,040 subjects again completed the TICS-J over 4 years. Physical activities contained moving ability, walking frequency, walking speed, the exercise frequency. At baseline, 870 elderly (age 75.87±4.96 (mean±SD) years, duration of education 11.05±2.41) showed normal cognitive functions and 170 (79.19±6.22, 9.61±2.23) showed cognitive impairment. The total TICS-J score was significantly higher in cognitive normal subjects compared with that of cognitive impaired subjects (36.02±1.89, 30.19±2.25, respectively, p<0.001). Logistic regression analyses showed that moving ability significantly reduced the risk of cognitive impairment in an unadjusted model, and walking speed also reduced the risk of cognitive impairment at baseline even in an adjusted model. Cognitive function at baseline might be a predictor of cognitive function over 4 years. The longitudinal study revealed that walking speed and exercise frequency significantly correlate with maintenance of cognitive function over 4 years. This study provides that physical activities, especially walking speed have significant correlation with cognitive function.

  6. Physical Activity, Functional Ability, and Obesity in Older Adults: A Gender Difference.

    Science.gov (United States)

    Gretebeck, Kimberlee A; Sabatini, LeAnn M; Black, David R; Gretebeck, Randall J

    2017-09-01

    Disability, institutionalization, and loss of independence may be directly caused or exacerbated by physical inactivity and obesity. The purpose of the current cross-sectional survey was to explore the impact of gender and obesity on functional ability tasks, physical activity, and psychosocial factors in older adults. Participants comprised 964 University retirees (55% female, mean age = 75.3 years, SD = 6.7 years) with a mean body mass index (BMI) of 26.1 kg/m 2 (SD = 4.7 kg/m 2 ). Results revealed significant gender and BMI interaction effects. Women were less active than men and obese women were most functionally impaired, particularly in activities that target lower extremity function, regardless of weight status. These findings suggest that physical activity interventions for older adults should focus on exercises that improve functional ability and are tailored to meet individual needs while considering weight and gender. Type, intensity, frequency, and duration of exercises should be individualized to limit injuries and improve functional ability and physical activity adherence. [Journal of Gerontological Nursing, 43(9), 38-46.]. Copyright 2017, SLACK Incorporated.

  7. Orthogonal use of a human tRNA synthetase active site to achieve multi-functionality

    Science.gov (United States)

    Zhou, Quansheng; Kapoor, Mili; Guo, Min; Belani, Rajesh; Xu, Xiaoling; Kiosses, William B.; Hanan, Melanie; Park, Chulho; Armour, Eva; Do, Minh-Ha; Nangle, Leslie A.; Schimmel, Paul; Yang, Xiang-Lei

    2011-01-01

    Protein multi-functionality is an emerging explanation for the complexity of higher organisms. In this regard, while aminoacyl tRNA synthetases catalyze amino acid activation for protein synthesis, some also act in pathways for inflammation, angiogenesis, and apoptosis. How multiple functions evolved and their relationship to the active site is not clear. Here structural modeling analysis, mutagenesis, and cell-based functional studies show that the potent angiostatic, natural fragment of human TrpRS associates via Trp side chains that protrude from the cognate cellular receptor VE-cadherin. Modeling indicates that (I prefer the way it was because the conclusion was reached not only by modeling, but more so by experimental studies.)VE-cadherin Trp side chains fit into the Trp-specific active site of the synthetase. Thus, specific side chains of the receptor mimic (?) amino acid substrates and expand the functionality of the active site of the synthetase. We propose that orthogonal use of the same active site may be a general way to develop multi-functionality of human tRNA synthetases and other proteins. PMID:20010843

  8. Relationship between the sensation of activity limitation and the results of functional assessment in asthma patients.

    Science.gov (United States)

    Vermeulen, Francois; Chirumberro, Audrey; Rummens, Peter; Bruyneel, Marie; Ninane, Vincent

    2017-08-01

    In asthma patients, the assessment of activity limitation is based on questions evaluating how limited the patient feels in their activities. However, the lack of functional data complicates the interpretation of the answers. We aimed to evaluate the intensity of relationships between the patient's perception of activity limitation and the results of several functional tests. Twenty patients complaining of asthma exacerbation were invited to complete three scores (Chronic Respiratory Disease questionnaire, Asthma Control Questionnaire, Hospital Anxiety and Depression scale). They also underwent lung function measurements, a 6-minute walk test and a cardio-pulmonary exercise test. In addition, physical activity was studied by actigraphy. Spearman's rank correlation coefficients between the patient's perception of activity limitation and each of the other parameters were analysed. Five parameters were significantly correlated with the perception of activity limitation: ACQ question 4, related to dyspnea (rs 0.74, p perception of activity limitation. In response to questions about limitation of activity, patients do not specifically answer mentioning physical limitation but rather the psychological burden associated with this constraint.

  9. FUNCTIONAL PROFILE OF ACTIVE OLDER ADULTS WITH LOW BACK PAIN, ACCORDING TO THE ICF

    Directory of Open Access Journals (Sweden)

    Andersom Ricardo Fréz

    Full Text Available ABSTRACT Introduction: The International Classification of Functioning, Disability and Health (ICF considers multiples aspects of functionality. It is believed that this tool can help to classify the functionality of older adults with low back pain (LBP . Objectives: To describe the functionality of active older adults with LBP according to the ICF. Methods: A transversal study was conducted using the brief ICF core set for low back pain, to establish functional profiles of 40 older adults. The ICF categories were considered valid when ≥20% of participants showed some disability. Results: Thirty-two of the 35 categories of the brief ICF core set could be considered representative of the sample. Conclusion: The brief ICF core set for LBP results demonstrated that this classification system is representative for describing the functional profile of the sample.

  10. Association of cytokine and matrix metalloproteinase profiles with disease activity and function in ankylosing spondylitis

    Science.gov (United States)

    2012-01-01

    Introduction The pathology of ankylosing spondylitis (AS) suggests that certain cytokines and matrix metalloproteinases (MMPs) might provide useful markers of disease activity. Serum levels of some cytokines and MMPs have been found to be elevated in active disease, but there is a general lack of information about biomarker profiles in AS and how these are related to disease activity and function. The purpose of this study was to investigate whether clinical measures of disease activity and function in AS are associated with particular profiles of circulating cytokines and MMPs. Methods Measurement of 30 cytokines, five MMPs and four tissue inhibitors of metalloproteinases was carried out using Luminex® technology on a well-characterised population of AS patients (n = 157). The relationship between biomarker levels and measures of disease activity (Bath ankylosing spondylitis disease activity index (BASDAI)), function (Bath ankylosing spondylitis functional index) and global health (Bath ankylosing spondylitis global health) was investigated. Principal component analysis was used to reduce the large number of biomarkers to a smaller set of independent components, which were investigated for their association with clinical measures. Further analyses were carried out using hierarchical clustering, multiple regression or multivariate logistic regression. Results Principal component analysis identified eight clusters consisting of various combinations of cytokines and MMPs. The strongest association with the BASDAI was found with a component consisting of MMP-8, MMP-9, hepatocyte growth factor and CXCL8, and was independent of C-reactive protein levels. This component was also associated with current smoking. Hierarchical clustering revealed two distinct patient clusters that could be separated on the basis of MMP levels. The high MMP cluster was associated with increased C-reactive protein, the BASDAI and the Bath ankylosing spondylitis functional index. Conclusions

  11. Physical function and physical activity assessment and promotion in the hemodialysis clinic: a qualitative study.

    Science.gov (United States)

    Painter, Patricia; Clark, Lauren; Olausson, Jill

    2014-09-01

    Despite practice guidelines (KDOQI [Kidney Disease Outcomes Quality Initiative]) recommending regular assessment of physical function and encouragement of physical activity, few clinics in the United States objectively assess physical function/physical activity or provide recommendations for physical activity in their patient care. Qualitative methods were used to develop an understanding of practice patterns related to physical function assessment and physical activity encouragement by dialysis staff. Data were collected in one outpatient university-based hemodialysis clinic. 15 patient care staff were interviewed and 6 patients were observed. Semistructured interviews of patient care staff were conducted, along with nonparticipant observations of the clinic environment and operations and review of archival materials. Coding of the interviews was descriptive, followed by interpretive coding by the research team. On-site field notes were transcribed for analysis. There was universal unawareness of the KDOQI guideline related to physical function/physical activity; however, all staff thought their patients would benefit from physical activity. There were no objective assessments of physical function and no resources or training to facilitate physical activity encouragement. Staff described deteriorating physical function in their patients, which was frustrating and disappointing. Barriers to physical activity included clinical/disease factors, staff "overaccommodation," and a system of dialysis care that facilitates sedentary behavior and does not require or incentivize clinics to promote physical activity. The patient care technicians were interested and thought that they had time to promote physical activity, but thought that they were unprepared to do so, indicating a need for education and training and a need to develop protocols to address the issue as routine practice. This was a single university-based center; however, because hemodialysis procedures are

  12. Scaling Behavior of Structure Functions of the Longitudinal Magnetic Field in Active Regions on the Sun

    Science.gov (United States)

    Abramenko, V. I.; Yurchyshyn, V. B.; Wang, H.; Spirock, T. J.; Goode, P. R.

    2002-05-01

    In the framework of a refined Kolmogorov's hypotheses, the scaling behavior of the BZ--component of the photospheric magnetic field is analyzed and compared with flaring activity in solar active regions. We used SOHO/MDI, Huairou (China) and Big Bear measurements of the Bz-component in the photosphere for nine active regions. We show that there is no universal behavior in the scaling of the Bz-structure functions for different active regions. Scaling for a given active region is caused by intermittency in the field, ǎrepsilon(B)(ěc x), of magnetic energy dissipation. When intermittency is weak, the Bz-field behaves as a passive scalar in the turbulent flow and the energy dissipation is largely determined by the dissipation of kinetic energy in active regions with low flare productivity. However, when the field ǎrepsilon(B)(ěc x) is highly intermittent, the structure functions behave as transverse structure functions of a fully developed turbulent vector field and the scaling of the energy dissipation is mostly determined by the dissipation of the magnetic energy (active regions with strong flaring productivity). We found that the spectrum of dissipation of the Bz component is strongly related to the level of flare productivity of a solar active region. When the flare productivity is high, the corresponding spectrum is less steep. We also found that during the evolution of an NOAA AR 9393 the Bz dissipation spectrum becomes less steep as the active region's flare activity increases. We suggest that the relation between scaling exponents and flare productivity of an active region enables us to monitor and forecast flare activity using only measurements of the Bz component of the photospheric magnetic field. This work was supported in part by the Ukrainian Ministry of Science and Education, NSF-ATM (0076602 and 0086999) and NASA (9682 and 9738) grants. SOHO is a project of international cooperation between ESA and NASA.

  13. Regulating cytokine function enhances safety and activity of genetic cancer therapies.

    Science.gov (United States)

    Chen, Hannah; Sampath, Padma; Hou, Weizhou; Thorne, Stephen H

    2013-01-01

    Genetic therapies, including transfected immune cells and viral vectors, continue to show clinical responses as systemically deliverable and targeted therapeutics, with the first such approaches having been approved for cancer treatment. The majority of these employ cytokine transgenes. However, expression of cytokines early after systemic delivery can result in increased toxicity and nonspecific induction of the immune response. In addition, premature immune-mediated clearance of the therapy may result, especially for viral-based approaches. Here, it was initially verified that cytokine (interleukin (IL)2) or chemokine (CCL5) expression from a systemically delivered oncolytic virus resulted in reduced oncolytic activity and suboptimal immune activation, while IL2 also resulted in increased toxicity. However, all these limitations could be overcome through incorporation of exogenous regulation of cytokine or chemokine transgene function through fusion of a small and externally controllable destabilizing domain to the protein of interest. Regulation allowed an initial phase without cytokine function, permitting enhanced delivery and oncolytic activity before activation of cytokine function and a subsequent phase of enhanced and tumor-targeted immunotherapeutic activity. As a result of this exogenous regulation of cytokine function, both oncolytic and immune-mediated mechanisms of action were optimized, greatly enhancing therapeutic activity, while toxicity was significantly reduced.

  14. Pain mediates the association between physical activity and the impact of fibromyalgia on daily function.

    Science.gov (United States)

    Umeda, Masataka; Corbin, Lisa W; Maluf, Katrina S

    2015-01-01

    This study quantified the association between recreational physical activity and daily function in women with fibromyalgia, and determined if this association is mediated by symptoms of pain, depression, or body mass. Twenty-three women diagnosed with fibromyalgia participated in an observational survey study. Recreational physical activity and the impact of fibromyalgia on daily function were assessed using the sport and leisure time physical activity subscales of the Baecke Physical Activity Questionnaire (BPAQ) and the Fibromyalgia Impact Questionnaire (FIQ), respectively. Potential mediators of the association between physical activity and daily function were assessed using the Visual Analogue Scale for pain intensity (VAS-Pain), the Beck Depression Inventory (BDI), and body mass index (BMI). BPAQ was inversely associated with FIQ (R (2) = 0.20) and VAS-Pain (R (2) = 0.39). VAS-Pain was positively associated with FIQ (R (2) = 0.23). The inverse association between BPAQ and FIQ was no longer significant after controlling for VAS-Pain. BDI was positively associated with FIQ (R (2) = 0.37), whereas BMI was not. BPAQ was not significantly associated with either BDI or BMI. These results indicate that the intensity of musculoskeletal pain, rather than depressive symptoms or body mass, mediates the association between physical activity and daily function among women with fibromyalgia.

  15. Neurotransmitters activate T-cells and elicit crucial functions via neurotransmitter receptors.

    Science.gov (United States)

    Levite, Mia

    2008-08-01

    Neurotransmitters are traditionally viewed as nerve-secreted molecules that trigger or inhibit neuronal functions. Yet, neurotransmitters bind also their neurotransmitter receptors in T-cells and directly activate or suppress T-cell functions. This review focuses only on the activating effects of neurotransmitters on T-cells, primarily naïve/resting cells, and covers dopamine, glutamate, serotonin, and few neuropeptides: GnRH-I, GnRH-II, substance P, somatostatin, CGRP, and neuropeptide Y. T-cells express many neurotransmitter receptors. These are regulated by TCR-activation, cytokines, or the neurotransmitters themselves, and are upregulated/downregulated in some human diseases. The context - whether the T-cells are naïve/resting or antigen/mitogen/cytokine-activated, the T-cell subset (CD4/CD8/Th1/Th2/Teff/Treg), neurotransmitter dose (low/optimal or high/excess), exact neurotransmitter receptors expressed, and the cytokine milieu - is crucial, and can determine either activation or suppression of T-cells by the same neurotransmitter. T-cells also produce many neurotransmitters. In summary, neurotransmitters activate vital T-cell functions in a direct, potent and specific manner, and may serve for communicating between the brain and the immune system to elicit an effective and orchestrated immune function, and for new therapeutic avenues, to improve T-cell eradication of cancer and infectious organisms.

  16. The active site of a carbohydrate esterase displays divergent catalytic and noncatalytic binding functions.

    Directory of Open Access Journals (Sweden)

    Cedric Montanier

    2009-03-01

    Full Text Available Multifunctional proteins, which play a critical role in many biological processes, have typically evolved through the recruitment of different domains that have the required functional diversity. Thus the different activities displayed by these proteins are mediated by spatially distinct domains, consistent with the specific chemical requirements of each activity. Indeed, current evolutionary theory argues that the colocalization of diverse activities within an enzyme is likely to be a rare event, because it would compromise the existing activity of the protein. In contrast to this view, a potential example of multifunctional recruitment into a single protein domain is provided by CtCel5C-CE2, which contains an N-terminal module that displays cellulase activity and a C-terminal module, CtCE2, which exhibits a noncatalytic cellulose-binding function but also shares sequence identity with the CE2 family of esterases. Here we show that, unlike other CE2 members, the CtCE2 domain displays divergent catalytic esterase and noncatalytic carbohydrate binding functions. Intriguingly, these diverse activities are housed within the same site on the protein. Thus, a critical component of the active site of CtCE2, the catalytic Ser-His dyad, in harness with inserted aromatic residues, confers noncatalytic binding to cellulose whilst the active site of the domain retains its esterase activity. CtCE2 catalyses deacetylation of noncellulosic plant structural polysaccharides to deprotect these substrates for attack by other enzymes. Yet it also acts as a cellulose-binding domain, which promotes the activity of the appended cellulase on recalcitrant substrates. The CE2 family encapsulates the requirement for multiple activities by biocatalysts that attack challenging macromolecular substrates, including the grafting of a second, powerful and discrete noncatalytic binding functionality into the active site of an enzyme. This article provides a rare example of

  17. Intrinsic muscle strength and voluntary activation of both lower limbs and functional performance after stroke.

    Science.gov (United States)

    Horstman, Astrid M; Beltman, Marijke J; Gerrits, Karin H; Koppe, Peter; Janssen, Thomas W; Elich, Peter; de Haan, Arnold

    2008-07-01

    The objective of this study was to assess the nature of muscle weakness in both legs after stroke compared with able-bodied control individuals and to examine whether there is a relationship between the degree of muscle weakness and coactivation of knee extensors and flexors as well as voluntary activation capacity of knee extensors of both paretic and non-paretic legs and indices of functional performance. Maximal voluntary isometric torques of knee extensors (MVCe) and flexors (MVCf) were determined in 14 patients (bilaterally) and 12 able-bodied controls. Simultaneous measurements were made of torque and surface EMG from agonist and antagonist muscles. Coactivation was calculated. Supramaximal triplets were evoked with electrical stimulation to estimate maximal torque capacity and degree of voluntary activation of knee extensors. MVCs, activation and coactivation parameters were correlated to scores of seven functional performance tests. MVCe, MVCf and voluntary activation were lower in paretic lower limb (PL) compared with both non-paretic lower limb (NL) and control. Besides, all these parameters of NL were also lower than control. Electrically evoked torque capacity of knee extensors of PL was about 60% of both NL and control, which were not significantly different from each other. Strong significant correlations between strength, as well as voluntary activation, and functional performance were found. Coactivation did not correlate well with functional performance. Thus, whereas for NL activation failure can explain weakness, for PL both activation failure and reduced intrinsic torque capacity are responsible for the severe weakness. Activation capacity and muscle strength correlated strongly to functional performance, while coactivation did not.

  18. Hormonal regulation of Na+/K+-dependent ATPase activity and pump function in corneal endothelial cells.

    Science.gov (United States)

    Hatou, Shin

    2011-10-01

    Na- and K-dependent ATPase (Na,K-ATPase) in the basolateral membrane of corneal endothelial cells plays an important role in the pump function of the corneal endothelium. We investigated the role of dexamethasone in the regulation of Na,K-ATPase activity and pump function in these cells. Mouse corneal endothelial cells were exposed to dexamethasone or insulin. ATPase activity was evaluated by spectrophotometric measurement, and pump function was measured using an Ussing chamber. Western blotting and immunocytochemistry were performed to measure the expression of the Na,K-ATPase α1-subunit. Dexamethasone increased Na,K-ATPase activity and the pump function of endothelial cells. Western blot analysis indicated that dexamethasone increased the expression of the Na,K-ATPase α1-subunit but decreased the ratio of active to inactive Na,K-ATPase α1-subunit. Insulin increased Na,K-ATPase activity and pump function of cultured corneal endothelial cells. These effects were transient and blocked by protein kinase C inhibitors and inhibitors of protein phosphatases 1 (PP1) and 2A (PP2A). Western blot analysis indicated that insulin decreased the amount of inactive Na,K-ATPase α1-subunit, but the expression of total Na,K-ATPase α1-subunit was unchanged. Immunocytochemistry showed that insulin increased cell surface expression of the Na,K-ATPase α1-subunit. Our results suggest that dexamethasone and insulin stimulate Na,K-ATPase activity in mouse corneal endothelial cells. The effect of dexamethasone activation in these cells was mediated by Na,K-ATPase synthesis and an increased enzymatic activity because of dephosphorylation of Na,K-ATPase α1-subunits. The effect of insulin is mediated by the protein kinase C, PP1, and/or PP2A pathways.

  19. Independence of protein kinase C-delta activity from activation loop phosphorylation: structural basis and altered functions in cells.

    Science.gov (United States)

    Liu, Yin; Belkina, Natalya V; Graham, Caroline; Shaw, Stephen

    2006-04-28

    Activation loop phosphorylation plays critical regulatory roles for many kinases. Unlike other protein kinase Cs (PKC), PKC-delta does not require phosphorylation of its activation loop (Thr-507) for in vitro activity. We investigated the structural basis for this unusual capacity and its relevance to PKC-delta function in intact cells. Mutational analysis demonstrated that activity without Thr-507 phosphorylation depends on 20 residues N-terminal to the kinase domain and a pair of phenylalanines (Phe-500/Phe-527) unique to PKC-delta in/near the activation loop. Molecular modeling demonstrated that these elements stabilize the activation loop by forming a hydrophobic chain of interactions from the C-lobe to activation loop to N-terminal (helical) extension. In cells PKC-delta mediates both apoptosis and transcription regulation. We found that the T507A mutant of the PKC-delta kinase domain resembled the corresponding wild type in mediating apoptosis in transfected HEK293T cells. But the T507A mutant was completely defective in AP-1 and NF-kappaB reporter assays. A novel assay in which the kinase domain of PKC-delta and its substrate (a fusion protein of PKC substrate peptide with green fluorescent protein) were co-targeted to lipid rafts revealed a major substrate-selective defect of the T507A mutant in phosphorylating the substrate in cells. In vitro analysis showed strong product inhibition on the T507A mutant with particular substrates whose characteristics suggest it contributes to the substrate selective defect of the PKC-delta T507A mutant in cells. Thus, activation loop phosphorylation of PKC-delta may regulate its function in cells in a novel way.

  20. Active life in old age. Combining measures of functional ability and social participation

    DEFF Research Database (Denmark)

    Avlund, K; Holstein, B E; Mortensen, Erik Lykke

    1999-01-01

    This paper describes a new measure of Active Life Expectancy, called Active Life Classification (ALC) in which the criterion for successful aging is a combination of good functional ability and high social participation. OBJECTIVES: 1) to describe the distribution of ALC among 75-year-old men......: For both men and women an active life (measured by ALC) was significantly associated with life satisfaction. For men only good self-rated health was related to ALC in the multivariate analysis. Among women high income, many social contacts, good self-rated health, good memory and lack of chronic diseases...... were associated with ALC. CONCLUSIONS: It is an advantage to combine functional ability and social participation in the description of quality of life in old age, as 1) a high social participation may compensate for a poor functional ability, and vice versa, 2) the combined measure is meaningful...

  1. Functional Based Adaptive and Fuzzy Sliding Controller for Non-Autonomous Active Suspension System

    Science.gov (United States)

    Huang, Shiuh-Jer; Chen, Hung-Yi

    In this paper, an adaptive sliding controller is developed for controlling a vehicle active suspension system. The functional approximation technique is employed to substitute the unknown non-autonomous functions of the suspension system and release the model-based requirement of sliding mode control algorithm. In order to improve the control performance and reduce the implementation problem, a fuzzy strategy with online learning ability is added to compensate the functional approximation error. The update laws of the functional approximation coefficients and the fuzzy tuning parameters are derived from the Lyapunov theorem to guarantee the system stability. The proposed controller is implemented on a quarter-car hydraulic actuating active suspension system test-rig. The experimental results show that the proposed controller suppresses the oscillation amplitude of the suspension system effectively.

  2. Effect of Leisure Activities on Inflammation and Cognitive Function in an Aging Sample

    Science.gov (United States)

    Friedman, Elliot; Quinn, Jill; Chen, Ding-Geng (Din); Mapstone, Mark

    2012-01-01

    Cardiovascular disease risk factors (CVDRFs) increase the risk of dementia. The purpose of this study was to examine whether leisure activities (mental, physical, and social activities) modified the effect of CVDRFs on inflammatory markers and cognitive function in middle and old age. A secondary-data analysis study was conducted using data from 405 middle-age participants (40 –59 years) and 342 old-age participants (60 – 84 years) who participated in the Survey of Midlife Development in the United States. CVDRFs were obtained from a combination of self-report medical history and blood-based biomarkers. Three CVDRF groups (≤1, 2, and ≥3 CVDRFs) were identified. More CVDRFs were significantly associated with higher levels of inflammatory markers in both age groups, and associated with lower levels of executive function in the old age group. CVDRFs were not related to the frequency of leisure activities in either age group. After controlling for covariates, higher levels of physical activities were significantly associated with lower levels of inflammatory markers, and higher levels of mental activities were associated with higher levels of cognitive function. In the old age group, physical activities also moderated the effect of CVDRFs on episodic memory, and mental activities moderated the effect of CVDRFs on interleukin-6. Multiple CVDRFs may be associated with poorer cognitive function and higher inflammatory markers, but middle-age and older adults with CVDRFs may not engage in frequent physical and cognitive activities that may be protective. It is important to develop strategies to facilitate engagement in these activities from midlife. PMID:22377120

  3. Caffeine restores myocardial cytochrome oxidase activity and improves cardiac function during sepsis.

    Science.gov (United States)

    Verma, Richa; Huang, Zhishan; Deutschman, Clifford S; Levy, Richard J

    2009-04-01

    Impaired mitochondrial function is a potential cause of sepsis-associated myocardial depression. Cytochrome oxidase (CcOX), the terminal oxidase of the electron transport chain, is inhibited in the septic heart. Caffeine increases CcOX activity by increasing cyclic adenosine monophosphate and protein kinase A activity. We hypothesized that caffeine will restore myocardial CcOX activity, increase cardiac function, and improve survival during sepsis. Prospective randomized controlled study. University hospital-based laboratory. One hundred twenty Sprague-Dawley male rats. Sprague-Dawley male rats underwent cecal ligation and puncture (CLP) or sham operation. At 24 and 48 hours, rats underwent intraperitoneal injection of either caffeine (7.5 mg/kg, the equivalent of 1-1.5 cups of coffee) or equal volume of saline. One hour following the 48-hour injection, steady-state CcOX kinetic activity was measured in isolated mitochondria and normalized to citrate synthase activity. Cardiac function was assessed using an isolated rat heart preparation and survival was tracked to 96 hours. CLP significantly decreased myocardial CcOX activity, oxygen consumption, left ventricular pressure, and pressure developed during isovolumic contraction (+dP/dt) and relaxation (-dP/dt). Caffeine restored CcOX activity and increased left ventricular pressure and +/-dP/dt toward sham values following CLP. Survival significantly improved following CLP in caffeine-injected animals compared with saline injection. Caffeine may be a novel therapy to treat sepsis-associated myocardial depression.

  4. Diversity of Dominant Bacterial Taxa in Activated Sludge Promotes Functional Resistance following Toxic Shock Loading

    KAUST Repository

    Saikaly, Pascal

    2010-12-14

    Examining the relationship between biodiversity and functional stability (resistance and resilience) of activated sludge bacterial communities following disturbance is an important first step towards developing strategies for the design of robust biological wastewater treatment systems. This study investigates the relationship between functional resistance and biodiversity of dominant bacterial taxa by subjecting activated sludge samples, with different levels of biodiversity, to toxic shock loading with cupric sulfate (Cu[II]), 3,5-dichlorophenol (3,5-DCP), or 4-nitrophenol (4-NP). Respirometric batch experiments were performed to determine the functional resistance of activated sludge bacterial community to the three toxicants. Functional resistance was estimated as the 30 min IC50 or the concentration of toxicant that results in a 50% reduction in oxygen utilization rate compared to a referential state represented by a control receiving no toxicant. Biodiversity of dominant bacterial taxa was assessed using polymerase chain reaction-terminal restriction fragment length polymorphism (PCR-T-RFLP) targeting the 16S ribosomal RNA (16S rRNA) gene. Statistical analysis of 30 min IC50 values and PCR-T-RFLP data showed a significant positive correlation (P<0.05) between functional resistance and microbial diversity for each of the three toxicants tested. To our knowledge, this is the first study showing a positive correlation between biodiversity of dominant bacterial taxa in activated sludge and functional resistance. In this system, activated sludge bacterial communities with higher biodiversity are functionally more resistant to disturbance caused by toxic shock loading. © 2010 Springer Science+Business Media, LLC.

  5. Functional Capacity and Levels of Physical Activity in Aging: A 3-Year Follow-up.

    Science.gov (United States)

    Tomás, Maria Teresa; Galán-Mercant, Alejandro; Carnero, Elvis Alvarez; Fernandes, Beatriz

    2017-01-01

    Over the last decades, the world elderly population has increased exponentially and this tendency will continue during the coming years; from 2000 to 2050, people over 60 will double and those over 80 will quadruple. Loss of independence occurs as people age due to mobility restrictions, frailty, and decreased functional fitness and cognitive abilities. Evidence has shown that appropriate programs and policies contribute to keep older adults healthy and independent over time. The purpose of this chapter is to report the results of our 3-year follow-up study designed to characterize functional physical fitness in a sample of Portuguese community-dwelling older adults to propose a set of functional parameters that decline the most. We studied a group of 43 elderly people, aged 60 and over. Variables assessed on the participants were anthropometric measurements, functional capacity with the Senior Fitness Test battery (muscle strength, aerobic endurance, flexibility, agility, and dynamic balance), handgrip strength, levels of physical activity, and balance. Three years after the first assessment, a second assessment of the same variables was conducted. We analyzed what were the variables that, for this group, were related with a healthier aging and the relation with different physical activity levels. Our study showed that the distance covered in 6-min walk test and handgrip strength seem to explain a great amount of variability on functional variables that have changed on this period (68% of balance, lower and upper functional strength, respectively) and the active participants showed less decrements with aging in anthropometric and functional variables than those inactive or insufficiently active ( p  activities should be given more attention as components of a community exercise program.

  6. Functional Capacity and Levels of Physical Activity in Aging: A 3-Year Follow-up

    Directory of Open Access Journals (Sweden)

    Maria Teresa Tomás

    2018-01-01

    Full Text Available Over the last decades, the world elderly population has increased exponentially and this tendency will continue during the coming years; from 2000 to 2050, people over 60 will double and those over 80 will quadruple. Loss of independence occurs as people age due to mobility restrictions, frailty, and decreased functional fitness and cognitive abilities. Evidence has shown that appropriate programs and policies contribute to keep older adults healthy and independent over time. The purpose of this chapter is to report the results of our 3-year follow-up study designed to characterize functional physical fitness in a sample of Portuguese community-dwelling older adults to propose a set of functional parameters that decline the most. We studied a group of 43 elderly people, aged 60 and over. Variables assessed on the participants were anthropometric measurements, functional capacity with the Senior Fitness Test battery (muscle strength, aerobic endurance, flexibility, agility, and dynamic balance, handgrip strength, levels of physical activity, and balance. Three years after the first assessment, a second assessment of the same variables was conducted. We analyzed what were the variables that, for this group, were related with a healthier aging and the relation with different physical activity levels. Our study showed that the distance covered in 6-min walk test and handgrip strength seem to explain a great amount of variability on functional variables that have changed on this period (68% of balance, lower and upper functional strength, respectively and the active participants showed less decrements with aging in anthropometric and functional variables than those inactive or insufficiently active (p < 0.05. Greater importance should be given to prescription of exercise targeting older adults and, specifically, walking and manual activities should be given more attention as components of a community exercise program.

  7. Alterations in brain activation during cognitive empathy are related to social functioning in schizophrenia.

    Science.gov (United States)

    Smith, Matthew J; Schroeder, Matthew P; Abram, Samantha V; Goldman, Morris B; Parrish, Todd B; Wang, Xue; Derntl, Birgit; Habel, Ute; Decety, Jean; Reilly, James L; Csernansky, John G; Breiter, Hans C

    2015-01-01

    Impaired cognitive empathy (ie, understanding the emotional experiences of others) is associated with poor social functioning in schizophrenia. However, it is unclear whether the neural activity underlying cognitive empathy relates to social functioning. This study examined the neural activation supporting cognitive empathy performance and whether empathy-related activation during correctly performed trials was associated with self-reported cognitive empathy and measures of social functioning. Thirty schizophrenia outpatients and 24 controls completed a cognitive empathy paradigm during functional magnetic resonance imaging. Neural activity corresponding to correct judgments about the expected emotional expression in a social interaction was compared in schizophrenia subjects relative to control subjects. Participants also completed a self-report measure of empathy and 2 social functioning measures (social competence and social attainment). Schizophrenia subjects demonstrated significantly lower accuracy in task performance and were characterized by hypoactivation in empathy-related frontal, temporal, and parietal regions as well as hyperactivation in occipital regions compared with control subjects during accurate cognitive empathy trials. A cluster with peak activation in the supplementary motor area (SMA) extending to the anterior midcingulate cortex (aMCC) correlated with social competence and social attainment in schizophrenia subjects but not controls. These results suggest that neural correlates of cognitive empathy may be promising targets for interventions aiming to improve social functioning and that brain activation in the SMA/aMCC region could be used as a biomarker for monitoring treatment response. © The Author 2014. Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  8. Immune activation is associated with decreased thymic function in asymptomatic, untreated HIV-infected individuals

    Directory of Open Access Journals (Sweden)

    Thandiwe Manjati

    2016-07-01

    Full Text Available Background: Reduced thymic function causes poor immunological reconstitution in human immunodeficiency virus (HIV-positive patients on combined antiretroviral therapy (cART.The association between immune activation and thymic function in asymptomatic HIV positive treatment-naive individuals has thus far not been investigated. Aims and objectives: To optimise a five-colour flow cytometric assay for measurement of thymic function by measuring recent thymic emigrants (RTEs in treatment-naive HIV-infected patients and healthy controls and correlate results with levels of immune activation, CD4 counts and viral load. Methods: Blood obtained from 53 consenting HIV-positive individuals and 32 controls recruited from HIV prevention and testing clinic in Cape Town, South Africa. RTEs were measured (CD3+/CD4+/CD45RA+/CD31+/CD62L+ and levels were correlated with CD4 counts of HIV-infected individuals, log viral load and levels of immune activation (CD8+/CD38+ T-cells. Results: HIV-infected individuals had reduced frequencies of RTEs when compared to controls (p = 0.0035. Levels of immune activation were inversely correlated with thymic function(p = 0.0403, and the thymic function in HIV-infected individuals showed no significant correlation with CD4 counts (p = 0.31559 and viral load (p = 0.20628. Conclusions: There was impaired thymic function in HIV-infected individuals, which was associated with increased levels of immune activation. The thymic dysfunction was not associated with CD4 counts and viral load. Immune activation may result in inflammatory damage to the thymus and subsequent thymic dysfunction, and CD4 counts and viral load may not necessarily reflect thymic dysfunction in HIV.

  9. New Insights into Activity Patterns in Children, Found Using Functional Data Analyses

    Science.gov (United States)

    Goldsmith, Jeff; Liu, Xinyue; Jacobson, Judith; Rundle, Andrew

    2016-01-01

    Introduction/Purpose Continuous monitoring of activity using accelerometers and other wearable devices provides objective, unbiased measurement of physical activity in minute-by-minute or finer resolutions. Accelerometers have already been widely deployed in studies of healthy aging, recovery of function after heart surgery, and other outcomes. While common analyses of accelerometer data focus on single summary variables, such as the total or average activity count, there is growing interest in the determinants of diurnal profiles of activity. Methods We use tools from functional data analysis (FDA), an area with an established statistical literature, to treat complete 24-hour diurnal profiles as outcomes in a regression model. We illustrate the use of such models by analyzing data collected in New York City from 420 children participating in a Head Start program. Covariates of interest include season, sex, BMI Z-score, presence of an asthma diagnosis, and mother’s birthplace. Results The FDA model finds several meaningful associations between several covariates and diurnal profiles of activity. In some cases, including shifted activity patterns for children of foreign-born mothers and time-specific effects of asthma on activity, these associations exist for covariates that are not associated with average activity count. Conclusion FDA provides a useful statistical framework for settings in which the effect of covariates on the timing of activity is of interest. The use of similar models in other applications should be considered, and we make code public to facilitate this process. PMID:27183122

  10. Metabolic mapping of functional activity in human subjects with the [18F]fluorodeoxyglucose technique

    International Nuclear Information System (INIS)

    Greenberg, J.H.; Reivich, M.; Alavi, A.

    1981-01-01

    The 2-[ 18 F]fluoro-2-deoxy-D-glucose technique was used to measure regional cerebral glucose utilization by human subjects during functional activation. Normal male volunteers subjected to one or more sensory stimuli exhibited focal increases in glucose metabolism in response to the stimulus. These results demonstrate that the technique is capable of providing functional maps in vivo related to both body region and submodality of sensory information in the human brain

  11. Trimethyloxonium modification of batrachotoxin-activated Na channels alters functionally important protein residues.

    OpenAIRE

    Cherbavaz, D B

    1995-01-01

    The extracellular side of single batrachotoxin-activated voltage-dependent Na channels isolated from rat skeletal muscle membranes incorporated into neutral planar lipid bilayers were treated in situ with the carboxyl methylating reagent, trimethyloxonium (TMO). These experiments were designed to determine whether TMO alters Na channel function by a general through-space electrostatic mechanism or by methylating specific carboxyl groups essential to channel function. TMO modification reduced ...

  12. Functionalized polymer-based spherical activated carbon for liquid and gas phase applications

    International Nuclear Information System (INIS)

    Schrage, Christian; Modrow, Antje; Fichtner, Sven; Giebelhausen, Jann Michael; Boehringer, Bertram

    2014-01-01

    Polymer-based spherical activated carbon (PBSAC) can be functionalized through the integration of reactive compounds. This offers new fields of applications for this adsorbent material. Impregnated PBSAC can be used as broadband sorbent material for respiratory protection, and for removal of certain metals from water, while the integration of nitrogen leads to a material suitable for the clean-up of gases. Functionalization through oxidation or integration of nitrogen atoms enables the concentration of valuable resources like uranium or gold.

  13. Activation of peroxisome proliferator-activated receptor gamma bypasses the function of the retinoblastoma protein in adipocyte differentiation

    DEFF Research Database (Denmark)

    Hansen, Jacob B.; Petersen, R K; Larsen, B M

    1999-01-01

    exit from the cell cycle after completion of clonal expansion following stimulation with adipogenic inducers. We conclude that ligand-induced activation of endogenous PPARgamma1 in mouse embryo fibroblasts is sufficient to initiate a transcriptional cascade resulting in induction of PPARgamma2 and C....../EBPalpha expression, withdrawal from the cell cycle, and terminal differentiation in the absence of a functional pRB....

  14. Performance of prioritized activities is not correlated with functional factors after grip reconstruction in tetraplegia.

    Science.gov (United States)

    Wangdell, Johanna; Fridén, Jan

    2011-06-01

    To investigate the correlation between perceived performance in prioritized activities and physical conditions related to grip reconstruction. Retrospective clinical outcome study. Forty-seven individuals with tetraplegia were included in the study. Each participant underwent tendon transfer surgery in the hand between November 2002 and April 2009 and had a complete 1-year follow-up. Functional characteristics and performance data were collected from our database and medical records. Patients' perceived performances in prioritized activities were recorded using the Canadian Occupational Performance Measurement. Preoperative data included age at surgery, time since injury, severity of injury, sensibility and hand dominance. At 1-year follow-up, grip strength, key pinch strength, finger pulp-to-palm distance, distance between thumb and index finger and wrist flexion were measured. Correlation rank coefficient was used to test the possible relationship between physical data and activity performance. There were improvements in both functional factors and in rated performance of prioritized activities after surgery. There was no correlation between performance change and any of the physical functions, the factors known before surgery, or the functional outcome factors. No correlation exists between a single functional outcome parameter and the patients' perceived performance of their prioritized goals in reconstructive hand surgery in tetraplegia.

  15. Time to loss of brain function and activity during circulatory arrest.

    Science.gov (United States)

    Pana, R; Hornby, L; Shemie, S D; Dhanani, S; Teitelbaum, J

    2016-08-01

    Brain function during the dying process and around the time of cardiac arrest is poorly understood. To better inform the clinical physiology of the dying process and organ donation practices, we performed a scoping review of the literature to assess time to loss of brain function and activity after circulatory arrest. Medline and Embase databases were searched from inception to June 2014 for articles reporting the time interval to loss of brain function or activity after loss of systemic circulation. Thirty-nine studies met selection criteria. Seven human studies and 10 animal studies reported that electroencephalography (EEG) activity is lost less than 30seconds after abrupt circulatory arrest. In the setting of existing brain injury, with progressive loss of oxygenated circulation, loss of EEG may occur before circulatory arrest. Cortical evoked potentials may persist for several minutes after loss of circulation. The time required to lose brain function varied according to clinical context and method by which this function is measured. Most studies show that clinical loss of consciousness and loss of EEG activity occur within 30seconds after abrupt circulatory arrest and may occur before circulatory arrest after progressive hypoxia-ischemia. Prospective clinical studies are required to confirm these observations. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. Context-specific Activity Repetition Training for Functional Outcome in Stroke Rehabilitation.

    Science.gov (United States)

    Ghous, Misbah; Malik, Arshad Nawaz

    2016-11-01

    Task-oriented, activity repetition training brings a marked improvement in stroke individuals. Maximum repetitions of taskoriented training in stroke patients can be achieved easily in a therapy session. The subject of this report exhibited limitations of walking function, impaired balance, and strength of the upper and lower limbs. Task-oriented activity repetition training (ART) was performed by the patient for 5 days a week consisting of 60 minutes with maximum repetitions for 6 weeks. There was a gradual increase in repetitions per session and after 6-week exercise programme, overall body strength, balance, gait velocity, walking endurance, and functional mobility of the patient was improved remarkably.

  17. Predicting receptor functionality of signaling lymphocyte activation molecule for measles virus hemagglutinin by docking simulation.

    Science.gov (United States)

    Suzuki, Yoshiyuki

    2017-05-01

    Predicting susceptibility of various species to a virus assists assessment of risk of interspecies transmission. Evaluation of receptor functionality may be useful in screening for susceptibility. In this study, docking simulation was conducted for measles virus hemagglutinin (MV-H) and immunoglobulin-like variable domain of signaling lymphocyte activation molecule (SLAM-V). It was observed that the docking scores for MV-H and SLAM-V correlated with the activity of SLAM as an MV receptor. These results suggest that the receptor functionality may be predicted from the docking scores of virion surface proteins and cellular receptor molecules. © 2017 The Societies and John Wiley & Sons Australia, Ltd.

  18. Exponential stability of delayed and impulsive cellular neural networks with partially Lipschitz continuous activation functions.

    Science.gov (United States)

    Song, Xueli; Xin, Xing; Huang, Wenpo

    2012-05-01

    The paper discusses exponential stability of distributed delayed and impulsive cellular neural networks with partially Lipschitz continuous activation functions. By relative nonlinear measure method, some novel criteria are obtained for the uniqueness and exponential stability of the equilibrium point. Our method abandons usual assumptions on global Lipschitz continuity, boundedness and monotonicity of activation functions. Our results are generalization and improvement of some existing ones. Finally, two examples and their simulations are presented to illustrate the correctness of our analysis. Copyright © 2012 Elsevier Ltd. All rights reserved.

  19. Histamine modulates multiple functional activities of monocyte-derived dendritic cell subsets via histamine receptor 2.

    Science.gov (United States)

    Simon, Tünde; Gogolák, Péter; Kis-Tóth, Katalin; Jelinek, Ivett; László, Valéria; Rajnavölgyi, Eva

    2012-02-01

    Expression of CD1a proteins in human monocyte-derived dendritic cells (DCs) specifies functionally distinct subsets with different inflammatory properties. Histamine is recognized as an inflammatory mediator released by various cell types including DCs. The diverse biological effects of histamine are mediated by G-protein-coupled histamine receptors (HRs), which are able to modulate the functional activities of DC subsets. The goal of the present study was to compare the expression and activity of HRs in the CD1a(-) and CD1a(+) monocyte-derived DC subsets and to test the effects of histamine on the differentiation, activation and functional activities of these subsets. We show that H2R is present at high levels in both DC subsets, whereas H1R and H4R are expressed in a subset-specific manner. Histamine shifts DC differentiation to the development of CD1a(-) DCs and modulates DC activation through its inhibitory effect on CD1a(+) DC differentiation. Histamine-induced reduction of CD1a(+) DCs is associated with increased secretion of IL-6 and IL-10, up-regulation of a typical combination of chemokines, expression C5aR1 by the CD1a(-) DC subset and enhanced migration of both activated DC subsets supported by the production of MMP-9 and MMP-12 enzymes. All these effects were shown to be mediated in a H2R-specific manner as revealed by the specific antagonist of the receptor. As H2R is expressed at high levels in both DC subsets, we propose that it may dominate the regulation of multiple DC functions. In contrast, H1R and H4R with opposing subset-related expression may have a regulatory or fine-tuning role in histamine-induced functional activities.

  20. [Functional status, self-rated health and level of physical activity of patients with osteoarthritis].

    Science.gov (United States)

    Val Jiménez, Carmen Llanos; López-Torres Hidalgo, Jesús; García Atienza, Eva María; Navarro Ruiz, María Soledad; Hernández Cerón, Inmaculada; Moreno de la Rosa, Lorena

    2017-04-01

    To describe the functional status and self-rated health of patients with osteoarthritis (OA) in Primary Care, and checking their relationship with the level of physical activity and sociodemographic characteristics. Study of prevalence and cross association. Primary Care Clinics. Adult patients with a diagnosis of OA in any joint in their clinical records. Out of a total of 487 selected, 346 (71.0%) took part in the study. Functional capacity (WOMAC scale), self-rated quality of life (EuroQol- 5D questionnaire), physical activity (IPAQ questionnaire), number of affected joints, pain level, and sociodemographic characteristics. A mean score of 30.2 (SD: 20.8; CI 95% CI: 28.0 to 32.4) was obtained on the WOMAC scale, with pain, stiffness, and functional capacity scores of 6.5 (SD: 4.8), 1.9 (SD: 2.0), and 21.7 (SD: 15.7), respectively. The score showed a linear trend (P<.001) compared to the level of physical activity, being 41.1 (SD: 19.9) in inactive subjects, 24.3 (SD: 18.7) in subjects with moderate activity, and 22.3 (SD: 19.8) in subjects with intense activity. In the multiple linear regression, the score on the WOMAC scale, as well as that obtained in self-rated health status, maintained their association with physical activity level after adjusting for sociodemographic variables and the number of affected joints. In patients with OA, pain and functional capacity are the most affected dimensions. Functional status and self-rated health status are higher in active patients, regardless of the number of joints affected and their demographic characteristics. Copyright © 2016 Elsevier España, S.L.U. All rights reserved.

  1. Comparison of the Lung Function in Response to Physical Activity in Two Different Climates

    Directory of Open Access Journals (Sweden)

    H. Marefati

    2016-09-01

    Full Text Available Aims: As factors that affect the pulmonary functioning, different climatic conditions and physical activities can produce respiratory diseases. The aim of this study was to compare the effects of physical activities on the pulmonary functioning in 12-14 years old females in two different Kerman and Gorgan climatic conditions. Materials & Methods: In the semi-experimental study, 128 female students of the elementary schools, aged between 12 and 14 years, were studied in Kerman and Gorgan (n=64 per city in 2013. The subjects were selected through random cluster method. The pulmonary functioning test was done before, immediately after, 7min after, and 20min after the physical activities. The peak expiratory flow (PEF, the expiratory volume in 1 second (FEV1, the forced vital capacity (FVC, the maximum expiratory flow at 50% of forced vital capacity (MEF50% were measured. More than 15% reductions in FEV1 and PEF after the activities were explained as Exercise Induced Asthma. Data was analyzed by SPSS 19 software using repeated measurement of variences and Chi-square tests. Findings: There was no significant difference in either FEV1 or PEF between Kerman and Gorgan cities (p>0.05. Nevertheless, there was a significant difference in the mean FVC between the cities (p=0.001. In total, there was more pulmonary-functioning drop after the activities in Kerman than Gorgan. Conclusion: More than average severe physical activities reduces the pulmonary capacity in 12-14 years old female, which cool and dry climate leads to more drop in the pulmonary functioning after the activities, as well as the continuance of the drop, than the wet climate.

  2. Hydrodynamics-based functional forms of activity metabolism: a case for the power-law polynomial function in animal swimming energetics.

    Directory of Open Access Journals (Sweden)

    Anthony Papadopoulos

    Full Text Available The first-degree power-law polynomial function is frequently used to describe activity metabolism for steady swimming animals. This function has been used in hydrodynamics-based metabolic studies to evaluate important parameters of energetic costs, such as the standard metabolic rate and the drag power indices. In theory, however, the power-law polynomial function of any degree greater than one can be used to describe activity metabolism for steady swimming animals. In fact, activity metabolism has been described by the conventional exponential function and the cubic polynomial function, although only the power-law polynomial function models drag power since it conforms to hydrodynamic laws. Consequently, the first-degree power-law polynomial function yields incorrect parameter values of energetic costs if activity metabolism is governed by the power-law polynomial function of any degree greater than one. This issue is important in bioenergetics because correct comparisons of energetic costs among different steady swimming animals cannot be made unless the degree of the power-law polynomial function derives from activity metabolism. In other words, a hydrodynamics-based functional form of activity metabolism is a power-law polynomial function of any degree greater than or equal to one. Therefore, the degree of the power-law polynomial function should be treated as a parameter, not as a constant. This new treatment not only conforms to hydrodynamic laws, but also ensures correct comparisons of energetic costs among different steady swimming animals. Furthermore, the exponential power-law function, which is a new hydrodynamics-based functional form of activity metabolism, is a special case of the power-law polynomial function. Hence, the link between the hydrodynamics of steady swimming and the exponential-based metabolic model is defined.

  3. Measuring everyday functional competence using the Rasch assessment of everyday activity limitations (REAL) item bank.

    Science.gov (United States)

    Oude Voshaar, Martijn A H; Ten Klooster, Peter M; Vonkeman, Harald E; van de Laar, Mart A F J

    2017-11-01

    Traditional patient-reported physical function instruments often poorly differentiate patients with mild-to-moderate disability. We describe the development and psychometric evaluation of a generic item bank for measuring everyday activity limitations in outpatient populations. Seventy-two items generated from patient interviews and mapped to the International Classification of Functioning, Disability and Health (ICF) domestic life chapter were administered to 1128 adults representative of the Dutch population. The partial credit model was fitted to the item responses and evaluated with respect to its assumptions, model fit, and differential item functioning (DIF). Measurement performance of a computerized adaptive testing (CAT) algorithm was compared with the SF-36 physical functioning scale (PF-10). A final bank of 41 items was developed. All items demonstrated acceptable fit to the partial credit model and measurement invariance across age, sex, and educational level. Five- and ten-item CAT simulations were shown to have high measurement precision, which exceeded that of SF-36 physical functioning scale across the physical function continuum. Floor effects were absent for a 10-item empirical CAT simulation, and ceiling effects were low (13.5%) compared with SF-36 physical functioning (38.1%). CAT also discriminated better than SF-36 physical functioning between age groups, number of chronic conditions, and respondents with or without rheumatic conditions. The Rasch assessment of everyday activity limitations (REAL) item bank will hopefully prove a useful instrument for assessing everyday activity limitations. T-scores obtained using derived measures can be used to benchmark physical function outcomes against the general Dutch adult population.

  4. Activation of auditory white matter tracts as revealed by functional magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Tae, Woo Suk [Kangwon National University, Neuroscience Research Institute, School of Medicine, Chuncheon (Korea, Republic of); Yakunina, Natalia; Nam, Eui-Cheol [Kangwon National University, Neuroscience Research Institute, School of Medicine, Chuncheon (Korea, Republic of); Kangwon National University, Department of Otolaryngology, School of Medicine, Chuncheon, Kangwon-do (Korea, Republic of); Kim, Tae Su [Kangwon National University Hospital, Department of Otolaryngology, Chuncheon (Korea, Republic of); Kim, Sam Soo [Kangwon National University, Neuroscience Research Institute, School of Medicine, Chuncheon (Korea, Republic of); Kangwon National University, Department of Radiology, School of Medicine, Chuncheon (Korea, Republic of)

    2014-07-15

    The ability of functional magnetic resonance imaging (fMRI) to detect activation in brain white matter (WM) is controversial. In particular, studies on the functional activation of WM tracts in the central auditory system are scarce. We utilized fMRI to assess and characterize the entire auditory WM pathway under robust experimental conditions involving the acquisition of a large number of functional volumes, the application of broadband auditory stimuli of high intensity, and the use of sparse temporal sampling to avoid scanner noise effects and increase signal-to-noise ratio. Nineteen healthy volunteers were subjected to broadband white noise in a block paradigm; each run had four sound-on/off alternations and was repeated nine times for each subject. Sparse sampling (TR = 8 s) was used. In addition to traditional gray matter (GM) auditory center activation, WM activation was detected in the isthmus and midbody of the corpus callosum (CC), tapetum, auditory radiation, lateral lemniscus, and decussation of the superior cerebellar peduncles. At the individual level, 13 of 19 subjects (68 %) had CC activation. Callosal WM exhibited a temporal delay of approximately 8 s in response to the stimulation compared with GM. These findings suggest that direct evaluation of the entire functional network of the central auditory system may be possible using fMRI, which may aid in understanding the neurophysiological basis of the central auditory system and in developing treatment strategies for various central auditory disorders. (orig.)

  5. The Cellular Bromodomain Protein Brd4 has Multiple Functions in E2-Mediated Papillomavirus Transcription Activation

    Directory of Open Access Journals (Sweden)

    Christine M. Helfer

    2014-08-01

    Full Text Available The cellular bromodomain protein Brd4 functions in multiple processes of the papillomavirus life cycle, including viral replication, genome maintenance, and gene transcription through its interaction with the viral protein, E2. However, the mechanisms by which E2 and Brd4 activate viral transcription are still not completely understood. In this study, we show that recruitment of positive transcription elongation factor b (P-TEFb, a functional interaction partner of Brd4 in transcription activation, is important for E2’s transcription activation activity. Furthermore, chromatin immunoprecipitation (ChIP analyses demonstrate that P-TEFb is recruited to the actual papillomavirus episomes. We also show that E2’s interaction with cellular chromatin through Brd4 correlates with its papillomavirus transcription activation function since JQ1(+, a bromodomain inhibitor that efficiently dissociates E2-Brd4 complexes from chromatin, potently reduces papillomavirus transcription. Our study identifies a specific function of Brd4 in papillomavirus gene transcription and highlights the potential use of bromodomain inhibitors as a method to disrupt the human papillomavirus (HPV life cycle.

  6. Effects of physiotherapy on pain and functional activities after cesarean delivery.

    Science.gov (United States)

    Çıtak Karakaya, İlkim; Yüksel, İnci; Akbayrak, Türkan; Demirtürk, Funda; Karakaya, Mehmet Gürhan; Ozyüncü, Özgür; Beksaç, Sinan

    2012-03-01

    To investigate the effects of a physiotherapy program on incision pain and functional activities in the early post-cesarean period. Fifty women were evaluated after Cesarean operation with regard to times of ambulation and return of bowel activity, intensity of incision pain, difficulty in functional activities and number of analgesics required additional to routine pain control procedure. Twenty-four women received only routine nursing care, and a physiotherapy program was applied to the study group (n = 26), additionally. Postoperative ambulation and return of bowel activity were earlier in the study group (p physiotherapy program in the early post-cesarean period in a wider perspective than the current literature, and are considered to be valuable for increasing the quality and productivity of the postnatal care, therefore improving well-being after childbirth.

  7. PMS2 endonuclease activity has distinct biological functions and is essential for genome maintenance

    Science.gov (United States)

    van Oers, Johanna M. M.; Roa, Sergio; Werling, Uwe; Liu, Yiyong; Genschel, Jochen; Sellers, Rani S.; Modrich, Paul; Scharff, Matthew D.; Edelmann, Winfried

    2010-01-01

    The DNA mismatch repair protein PMS2 was recently found to encode a novel endonuclease activity. To determine the biological functions of this activity in mammals, we generated endonuclease-deficient Pms2E702K knock-in mice. Pms2EK/EK mice displayed increased genomic mutation rates and a strong cancer predisposition. In addition, class switch recombination, but not somatic hypermutation, was impaired in Pms2EK/EK B cells, indicating a specific role in Ig diversity. In contrast to Pms2−/− mice, Pms2EK/EK male mice were fertile, indicating that this activity is dispensable in spermatogenesis. Therefore, the PMS2 endonuclease activity has distinct biological functions and is essential for genome maintenance and tumor suppression. PMID:20624957

  8. Bioactive components and functional properties of biologically activated cereal grains: A bibliographic review.

    Science.gov (United States)

    Singh, Arashdeep; Sharma, Savita

    2017-09-22

    Whole grains provide energy, nutrients, fibers, and bioactive compounds that may synergistically contribute to their protective effects. A wide range of these compounds is affected by germination. While some compounds, such as β-glucans are degraded, others, like antioxidants and total phenolics are increased by means of biological activation of grains. The water and oil absorption capacity as well as emulsion and foaming capacity of biologically activated grains are also improved. Application of biological activation of grains is of emerging interest, which may significantly enhance the nutritional, functional, and bioactive content of grains, as well as improve palatability of grain foods in a natural way. Therefore, biological activation of cereals can be a way to produce food grains enriched with health-promoting compounds and enhanced functional attributes.

  9. Contribution of generative leisure activities to cognitive function in elderly Sri Lankan adults.

    Science.gov (United States)

    Maselko, Joanna; Sebranek, Matthew; Mun, Mirna H; Perera, Bilesha; Ahs, Jill; Ostbye, Truls

    2014-09-01

    To examine the unique contribution of generative leisure activities, defined as activities motivated by a concern for others and a need to contribute something to the next generation. Cross-sectional survey. Peri-urban and rural area in southern Sri Lanka. Community-dwelling adults aged 60 and older (N = 252). The main predictors were leisure activities, grouped into generative, social, or solitary. The main outcome was cognitive function, assessed using the Montreal Cognitive Assessment (MoCA) and the Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE). More-frequent engagement in generative leisure activities was associated with higher levels of cognitive function, independent of the effect of other social and solitary leisure activities. In a fully adjusted model combining all three leisure activities, generative activities independently predicted cognitive function as measured using the MoCA (β = 0.47, 95% confidence interval (CI) = 0.11-0.83) and the IQCODE (β = -0.81, 95% CI = -1.54 to -0.09). In this combined model, solitary activities were also independently associated with slower cognitive decline using the MoCA (β = 0.40, 95% CI = 0.16-0.64) but not the IQCODE (β = -0.38, 95% CI = -0.88-0.12); the association with social activities did not reach statistical significance with either measure. These associations did not differ meaningfully according to sex. Generative leisure activities are a promising area for the development of interventions aimed at reducing cognitive decline in elderly adults. © 2014, Copyright the Authors Journal compilation © 2014, The American Geriatrics Society.

  10. Metabolic Activity and Functional Diversity Changes in Sediment Prokaryotic Communities Organically Enriched with Mussel Biodeposits

    OpenAIRE

    Pollet, Thomas; Cloutier, Olivier; Nozais, Christian; McKindsey, Christopher W.; Archambault, Philippe

    2015-01-01

    This experimental microcosm study reports the influence of organic enrichments by mussel biodeposits on the metabolic activity and functional diversity of benthic prokaryotic communities. The different biodeposit enrichment regimes created, which mimicked the quantity of faeces and pseudo-faeces potentially deposited below mussel farms, show a clear stimulatory effect of this organic enrichment on prokaryotic metabolic activity. This effect was detected once a certain level of biodeposition w...

  11. Approaches to Modelling the Dynamical Activity of Brain Function Based on the Electroencephalogram

    Science.gov (United States)

    Liley, David T. J.; Frascoli, Federico

    The brain is arguably the quintessential complex system as indicated by the patterns of behaviour it produces. Despite many decades of concentrated research efforts, we remain largely ignorant regarding the essential processes that regulate and define its function. While advances in functional neuroimaging have provided welcome windows into the coarse organisation of the neuronal networks that underlie a range of cognitive functions, they have largely ignored the fact that behaviour, and by inference brain function, unfolds dynamically. Modelling the brain's dynamics is therefore a critical step towards understanding the underlying mechanisms of its functioning. To date, models have concentrated on describing the sequential organisation of either abstract mental states (functionalism, hard AI) or the objectively measurable manifestations of the brain's ongoing activity (rCBF, EEG, MEG). While the former types of modelling approach may seem to better characterise brain function, they do so at the expense of not making a definite connection with the actual physical brain. Of the latter, only models of the EEG (or MEG) offer a temporal resolution well matched to the anticipated temporal scales of brain (mental processes) function. This chapter will outline the most pertinent of these modelling approaches, and illustrate, using the electrocortical model of Liley et al, how the detailed application of the methods of nonlinear dynamics and bifurcation theory is central to exploring and characterising their various dynamical features. The rich repertoire of dynamics revealed by such dynamical systems approaches arguably represents a critical step towards an understanding of the complexity of brain function.

  12. Prediction of cloud condensation nuclei activity for organic compounds using functional group contribution methods

    Science.gov (United States)

    Petters, M. D.; Kreidenweis, S. M.; Ziemann, P. J.

    2016-01-01

    A wealth of recent laboratory and field experiments demonstrate that organic aerosol composition evolves with time in the atmosphere, leading to changes in the influence of the organic fraction to cloud condensation nuclei (CCN) spectra. There is a need for tools that can realistically represent the evolution of CCN activity to better predict indirect effects of organic aerosol on clouds and climate. This work describes a model to predict the CCN activity of organic compounds from functional group composition. Following previous methods in the literature, we test the ability of semi-empirical group contribution methods in Köhler theory to predict the effective hygroscopicity parameter, kappa. However, in our approach we also account for liquid-liquid phase boundaries to simulate phase-limited activation behavior. Model evaluation against a selected database of published laboratory measurements demonstrates that kappa can be predicted within a factor of 2. Simulation of homologous series is used to identify the relative effectiveness of different functional groups in increasing the CCN activity of weakly functionalized organic compounds. Hydroxyl, carboxyl, aldehyde, hydroperoxide, carbonyl, and ether moieties promote CCN activity while methylene and nitrate moieties inhibit CCN activity. The model can be incorporated into scale-bridging test beds such as the Generator of Explicit Chemistry and Kinetics of Organics in the Atmosphere (GECKO-A) to evaluate the evolution of kappa for a complex mix of organic compounds and to develop suitable parameterizations of CCN evolution for larger-scale models.

  13. c-Met and Other Cell Surface Molecules: Interaction, Activation and Functional Consequences

    Directory of Open Access Journals (Sweden)

    Giuditta Viticchiè

    2015-01-01

    Full Text Available The c-Met receptor, also known as the HGF receptor, is one of the most studied tyrosine kinase receptors, yet its biological functions and activation mechanisms are still not fully understood. c-Met has been implicated in embryonic development and organogenesis, in tissue remodelling homeostasis and repair and in cancer metastasis. These functions are indicative of the many cellular processes in which the receptor plays a role, including cell motility, scattering, survival and proliferation. In the context of malignancy, sustained activation of c-Met leads to a signalling cascade involving a multitude of kinases that initiate an invasive and metastatic program. Many proteins can affect the activation of c-Met, including a variety of other cell surface and membrane-spanning molecules or receptors. Some cell surface molecules share structural homology with the c-Met extracellular domain and can activate c-Met via clustering through this domain (e.g., plexins, whereas other receptor tyrosine kinases can enhance c-Met activation and signalling through intracellular signalling cascades (e.g., EGFR. In this review, we provide an overview of c-Met interactions and crosstalk with partner molecules and the functional consequences of these interactions on c-Met activation and downstream signalling, c-Met intracellular localization/recycling and c-Met degradation.

  14. Hypnosis and pain perception: An Activation Likelihood Estimation (ALE) meta-analysis of functional neuroimaging studies.

    Science.gov (United States)

    Del Casale, Antonio; Ferracuti, Stefano; Rapinesi, Chiara; De Rossi, Pietro; Angeletti, Gloria; Sani, Gabriele; Kotzalidis, Georgios D; Girardi, Paolo

    2015-12-01

    Several studies reported that hypnosis can modulate pain perception and tolerance by affecting cortical and subcortical activity in brain regions involved in these processes. We conducted an Activation Likelihood Estimation (ALE) meta-analysis on functional neuroimaging studies of pain perception under hypnosis to identify brain activation-deactivation patterns occurring during hypnotic suggestions aiming at pain reduction, including hypnotic analgesic, pleasant, or depersonalization suggestions (HASs). We searched the PubMed, Embase and PsycInfo databases; we included papers published in peer-reviewed journals dealing with functional neuroimaging and hypnosis-modulated pain perception. The ALE meta-analysis encompassed data from 75 healthy volunteers reported in 8 functional neuroimaging studies. HASs during experimentally-induced pain compared to control conditions correlated with significant activations of the right anterior cingulate cortex (Brodmann's Area [BA] 32), left superior frontal gyrus (BA 6), and right insula, and deactivation of right midline nuclei of the thalamus. HASs during experimental pain impact both cortical and subcortical brain activity. The anterior cingulate, left superior frontal, and right insular cortices activation increases could induce a thalamic deactivation (top-down inhibition), which may correlate with reductions in pain intensity. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Clinical studies of brain functional images by motor activation using single photon emission computed tomography

    International Nuclear Information System (INIS)

    Kawaguchi, Masahiro

    1998-01-01

    Thirty participants (10 normal controls; group A, 5 patients with brain tumors located near central sulcus without hemiparesis; group B, 10 patients with brain tumors located near central sulcus with hemiparesis; group C, and 5 patients with brain tumors besides the central regions with hemiparesis; group D) were enrolled. The images were performed by means of split-dose method with 99m Tc-ECD at rest condition (SPECT 1) and during hand grasping (SPECT 2). The activation SPECT were obtained by subtracting SPECT 1 from SPECT 2, and the functional mapping was made by the strict registration of the activation SPECT with 3D MRI. To evaluate the changes of CBF (%ΔCBF) of the sensorimotor and supplementary motor areas on the functional mapping, ratio of the average counts of SPECT 1 and SPECT 2 was calculated and statistically compared. The functional activation paradigms caused a significant increase of CBF in the sensorimotor area contra-lateral to the stimulated hand, although the sensorimotor area and the central sulcus in groups B and C were dislocated, compared with hemisphere of non-tumor side. The sensorimotor area ipsi-lateral to the stimulated hand could be detected in almost of all subjects. The supplementary motor area could be detected in all subjects. In group A, the average %ΔCBF were up 24.1±4.3% in the contra-lateral sensorimotor area, and 22.3±3.6% in the supplementary motor area, respectively. The average %ΔCBF in the contra-lateral sensorimotor area of group D was significantly higher than that of group A. The brain functional mapping by motor activation using SPECT could localize the area of cortical motor function in normal volunteers and patients with brain tumors. The changes of regional CBF by activation SPECT precisely assess the cortical motor function even in patients with brain tumors located near central sulcus. (K.H.)

  16. Task control signals in pediatric Tourette syndrome show evidence of immature and anomalous functional activity

    Directory of Open Access Journals (Sweden)

    Jessica A Church

    2009-11-01

    Full Text Available Tourette Syndrome (TS is a pediatric movement disorder that may affect control signaling in the brain. Previous work has proposed a dual-networks architecture of control processing involving a task-maintenance network and an adaptive control network (Dosenbach et al., 2008. A prior resting-state functional connectivity MRI (rs-fcMRI analysis in TS has revealed functional immaturity in both putative control networks, with “anomalous” correlations (i.e. correlations outside the typical developmental range limited to the adaptive control network (Church et al., 2009. The present study used functional MRI (fMRI to study brain activity related to adaptive control (by studying start-cues signals, and to task-maintenance (by studying signals sustained across a task set. Two hypotheses from the previous rs-fcMRI results were tested. First, adaptive control (i.e., start-cue activity will be altered in TS, including activity inconsistent with typical development (“anomalous”. Second, group differences found in task maintenance (i.e., sustained activity will be consistent with functional immaturity in TS. We examined regions found through a direct comparison of adolescents with and without TS, as well as regions derived from a previous investigation that showed differences between unaffected children and adults. The TS group showed decreased start-cue signal magnitude in regions where start-cue activity is unchanged over typical development, consistent with anomalous adaptive control. The TS group also had higher magnitude sustained signals in frontal cortex regions that overlapped with regions showing differences over typical development, consistent with immature task maintenance in TS. The results demonstrate task-related fMRI signal differences anticipated by the atypical functional connectivity found previously in adolescents with TS, strengthening the evidence for functional immaturity and anomalous signaling in control networks in adolescents

  17. Muscle sympathetic nerve activity is related to a surrogate marker of endothelial function in healthy individuals.

    Directory of Open Access Journals (Sweden)

    Yrsa Bergmann Sverrisdóttir

    Full Text Available BACKGROUND: Evidence from animal studies indicates the importance of an interaction between the sympathetic nervous system and the endothelium for cardiovascular regulation. However the interaction between these two systems remains largely unexplored in humans. The aim of this study was to investigate whether directly recorded sympathetic vasoconstrictor outflow is related to a surrogate marker of endothelial function in healthy individuals. METHODS AND RESULTS: In 10 healthy normotensive subjects (3 f/7 m, (age 37+/-11 yrs, (BMI 24+/-3 kg/m(2 direct recordings of sympathetic action potentials to the muscle vascular bed (MSNA were performed and endothelial function estimated with the Reactive Hyperaemia- Peripheral Arterial Tonometry (RH-PAT technique. Blood samples were taken and time spent on leisure-time physical activities was estimated. In all subjects the rate between resting flow and the maximum flow, the Reactive Hyperemic index (RH-PAT index, was within the normal range (1.9-3.3 and MSNA was as expected for age and gender (13-44 burst/minute. RH-PAT index was inversely related to MSNA (r = -0.8, p = 0.005. RH-PAT index and MSNA were reciprocally related to time (h/week spent on physical activity (p = 0.005 and p = 0.006 respectively and platelet concentration (PLT (p = 0.02 and p = 0.004 respectively. CONCLUSIONS: Our results show that sympathetic nerve activity is related to a surrogate marker of endothelial function in healthy normotensive individuals, indicating that sympathetic outflow may be modulated by changes in endothelial function. In this study time spent on physical activity is identified as a predictor of sympathetic nerve activity and endothelial function in a group of healthy individuals. The results are of importance in understanding mechanisms underlying sympathetic activation in conditions associated with endothelial dysfunction and emphasise the importance of a daily exercise routine for maintenance of cardiovascular

  18. Muscle sympathetic nerve activity is related to a surrogate marker of endothelial function in healthy individuals.

    Science.gov (United States)

    Sverrisdóttir, Yrsa Bergmann; Jansson, Linda Marie; Hägg, Ulrika; Gan, Li-Ming

    2010-02-17

    Evidence from animal studies indicates the importance of an interaction between the sympathetic nervous system and the endothelium for cardiovascular regulation. However the interaction between these two systems remains largely unexplored in humans. The aim of this study was to investigate whether directly recorded sympathetic vasoconstrictor outflow is related to a surrogate marker of endothelial function in healthy individuals. In 10 healthy normotensive subjects (3 f/7 m), (age 37+/-11 yrs), (BMI 24+/-3 kg/m(2)) direct recordings of sympathetic action potentials to the muscle vascular bed (MSNA) were performed and endothelial function estimated with the Reactive Hyperaemia- Peripheral Arterial Tonometry (RH-PAT) technique. Blood samples were taken and time spent on leisure-time physical activities was estimated. In all subjects the rate between resting flow and the maximum flow, the Reactive Hyperemic index (RH-PAT index), was within the normal range (1.9-3.3) and MSNA was as expected for age and gender (13-44 burst/minute). RH-PAT index was inversely related to MSNA (r = -0.8, p = 0.005). RH-PAT index and MSNA were reciprocally related to time (h/week) spent on physical activity (p = 0.005 and p = 0.006 respectively) and platelet concentration (PLT) (p = 0.02 and p = 0.004 respectively). Our results show that sympathetic nerve activity is related to a surrogate marker of endothelial function in healthy normotensive individuals, indicating that sympathetic outflow may be modulated by changes in endothelial function. In this study time spent on physical activity is identified as a predictor of sympathetic nerve activity and endothelial function in a group of healthy individuals. The results are of importance in understanding mechanisms underlying sympathetic activation in conditions associated with endothelial dysfunction and emphasise the importance of a daily exercise routine for maintenance of cardiovascular health.

  19. The effects of active mobilisation and rehabilitation in ICU on mortality and function: a systematic review.

    Science.gov (United States)

    Tipping, Claire J; Harrold, Meg; Holland, Anne; Romero, Lorena; Nisbet, Travis; Hodgson, Carol L

    2017-02-01

    Early active mobilisation and rehabilitation in the intensive care unit (ICU) is being used to prevent the long-term functional consequences of critical illness. This review aimed to determine the effect of active mobilisation and rehabilitation in the ICU on mortality, function, mobility, muscle strength, quality of life, days alive and out of hospital to 180 days, ICU and hospital lengths of stay, duration of mechanical ventilation and discharge destination, linking outcomes with the World Health Organization International Classification of Function Framework. A PRISMA checklist-guided systematic review and meta-analysis of randomised and controlled clinical trials. Fourteen studies of varying quality including a total of 1753 patients were reviewed. Active mobilisation and rehabilitation had no impact on short- or long-term mortality (p > 0.05). Meta-analysis showed that active mobilisation and rehabilitation led to greater muscle strength (body function) at ICU discharge as measured using the Medical Research Council Sum Score (mean difference 8.62 points, 95% confidence interval (CI) 1.39-15.86), greater probability of walking without assistance (activity limitation) at hospital discharge (odds ratio 2.13, 95% CI 1.19-3.83), and more days alive and out of hospital to day 180 (participation restriction) (mean difference 9.69, 95% CI 1.7-17.66). There were no consistent effects on function, quality of life, ICU or hospital length of stay, duration of mechanical ventilation or discharge destination. Active mobilisation and rehabilitation in the ICU has no impact on short- and long-term mortality, but may improve mobility status, muscle strength and days alive and out of hospital to 180 days. CRD42015029836.

  20. Soluble Milk Protein Supplementation with Moderate Physical Activity Improves Locomotion Function in Aging Rats.

    Directory of Open Access Journals (Sweden)

    Aude Lafoux

    Full Text Available Aging is associated with a loss of muscle mass and functional capacity. Present study was designed to compare the impact of specific dairy proteins on muscular function with or without a low-intensity physical activity program on a treadmill in an aged rat model. We investigated the effects of nutritional supplementation, five days a week over a 2-month period with a slow digestible protein, casein or fast digestible proteins, whey or soluble milk protein, on strength and locomotor parameters in sedentary or active aged Wistar RjHan rats (17-19 months of age. An extensive gait analysis was performed before and after protein supplementation. After two months of protein administration and activity program, muscle force was evaluated using a grip test, spontaneous activity using an open-field and muscular mass by specific muscle sampling. When aged rats were supplemented with proteins without exercise, only minor effects of different diets on muscle mass and locomotion were observed: higher muscle mass in the casein group and improvement of stride frequencies with soluble milk protein. By contrast, supplementation with soluble milk protein just after physical activity was more effective at improving overall skeletal muscle function in old rats compared to casein. For active old rats supplemented with soluble milk protein, an increase in locomotor activity in the open field and an enhancement of static and dynamic gait parameters compared to active groups supplemented with casein or whey were observed without any differences in muscle mass and forelimb strength. These results suggest that consumption of soluble milk protein as a bolus immediately after a low intensity physical activity may be a suitable nutritional intervention to prevent decline in locomotion in aged rats and strengthen the interest to analyze the longitudinal aspect of locomotion in aged rodents.

  1. Soluble Milk Protein Supplementation with Moderate Physical Activity Improves Locomotion Function in Aging Rats.

    Science.gov (United States)

    Lafoux, Aude; Baudry, Charlotte; Bonhomme, Cécile; Le Ruyet, Pascale; Huchet, Corinne

    2016-01-01

    Aging is associated with a loss of muscle mass and functional capacity. Present study was designed to compare the impact of specific dairy proteins on muscular function with or without a low-intensity physical activity program on a treadmill in an aged rat model. We investigated the effects of nutritional supplementation, five days a week over a 2-month period with a slow digestible protein, casein or fast digestible proteins, whey or soluble milk protein, on strength and locomotor parameters in sedentary or active aged Wistar RjHan rats (17-19 months of age). An extensive gait analysis was performed before and after protein supplementation. After two months of protein administration and activity program, muscle force was evaluated using a grip test, spontaneous activity using an open-field and muscular mass by specific muscle sampling. When aged rats were supplemented with proteins without exercise, only minor effects of different diets on muscle mass and locomotion were observed: higher muscle mass in the casein group and improvement of stride frequencies with soluble milk protein. By contrast, supplementation with soluble milk protein just after physical activity was more effective at improving overall skeletal muscle function in old rats compared to casein. For active old rats supplemented with soluble milk protein, an increase in locomotor activity in the open field and an enhancement of static and dynamic gait parameters compared to active groups supplemented with casein or whey were observed without any differences in muscle mass and forelimb strength. These results suggest that consumption of soluble milk protein as a bolus immediately after a low intensity physical activity may be a suitable nutritional intervention to prevent decline in locomotion in aged rats and strengthen the interest to analyze the longitudinal aspect of locomotion in aged rodents.

  2. Physical Activity in Advanced Age: Physical Activity, Function, and Mortality in Advanced Age: A Longitudinal Follow Up (LiLACS NZ).

    Science.gov (United States)

    Mace Firebaugh, Casey; Moyes, Simon; Jatrana, Santosh; Rolleston, Anna; Kerse, Ngaire

    2018-01-18

    The relationship between physical activity, function, and mortality is not established in advanced age. Physical activity, function, and mortality were followed in a cohort of Māori and non-Māori adults living in advanced age for a period of six years. Generalised Linear regression models were used to analyse the association between physical activity and NEADL while Kaplan-Meier survival analysis, and Cox-proportional hazard models were used to assess the association between the physical activity and mortality. The Hazard Ratio for mortality for those in the least active physical activity quartile was 4.1 for Māori and 1.8 for non- Māori compared to the most active physical activity quartile. There was an inverse relationship between physical activity and mortality, with lower hazard ratios for mortality at all levels of physical activity. Higher levels of physical activity were associated with lower mortality and higher functional status in advanced aged adults.

  3. Coevolution between human's anticancer activities and functional foods from crop origin center in the world.

    Science.gov (United States)

    Zeng, Ya-Wen; Du, Juan; Pu, Xiao-Ying; Yang, Jia-Zhen; Yang, Tao; Yang, Shu-Ming; Yang, Xiao-Meng

    2015-01-01

    Cancer is the leading cause of death around the world. Anticancer activities from many functional food sources have been reported in years, but correlation between cancer prevalence and types of food with anticancer activities from crop origin center in the world as well as food source with human migration are unclear. Hunger from food shortage is the cause of early human evolution from Africa to Asia and later into Eurasia. The richest functional foods are found in crop origin centers, housing about 70% in the world populations. Crop origin centers have lower cancer incidence and mortality in the world, especially Central Asia, Middle East, Southwest China, India and Ethiopia. Asia and Africa with the richest anticancer crops is not only the most important evolution base of humans and origin center of anticancer functional crop, but also is the lowest mortality and incidence of cancers in the world. Cancer prevention of early human migrations was associated with functional foods from crop origin centers, especially Asia with four centers and one subcenter of crop origin, accounting for 58% of the world population. These results reveal that coevolution between human's anticancer activities associated with functional foods for crop origin centers, especially in Asia and Africa.

  4. Suboptimal Muscle Synergy Activation Patterns Generalize their Motor Function across Postures.

    Science.gov (United States)

    Sohn, M Hongchul; Ting, Lena H

    2016-01-01

    We used a musculoskeletal model to investigate the possible biomechanical and neural bases of using consistent muscle synergy patterns to produce functional motor outputs across different biomechanical conditions, which we define as generalizability. Experimental studies in cats demonstrate that the same muscle synergies are used during reactive postural responses at widely varying configurations, producing similarly-oriented endpoint force vectors with respect to the limb axis. However, whether generalizability across postures arises due to similar biomechanical properties or to neural selection of a particular muscle activation pattern has not been explicitly tested. Here, we used a detailed cat hindlimb model to explore the set of feasible muscle activation patterns that produce experimental synergy force vectors at a target posture, and tested their generalizability by applying them to different test postures. We used three methods to select candidate muscle activation patterns: (1) randomly-selected feasible muscle activation patterns, (2) optimal muscle activation patterns minimizing muscle effort at a given posture, and (3) generalizable muscle activation patterns that explicitly minimized deviations from experimentally-identified synergy force vectors across all postures. Generalizability was measured by the deviation between the simulated force direction of the candidate muscle activation pattern and the experimental synergy force vectors at the test postures. Force angle deviations were the greatest for the randomly selected feasible muscle activation patterns (e.g., >100°), intermediate for effort-wise optimal muscle activation patterns (e.g., ~20°), and smallest for generalizable muscle activation patterns (e.g., synergy force vector was reduced by ~45% when generalizability requirements were imposed. Muscles recruited in the generalizable muscle activation patterns had less sensitive torque-producing characteristics to changes in postures. We

  5. Functional and psychological variables both affect daily physical activity in COPD : A structural equations model

    NARCIS (Netherlands)

    Altenburg, Wytske A.; Bossenbroek, Linda; de Greef, Mathieu H. G.; Kerstjens, Huib A. M.; ten Hacken, Nick H. T.; Wempe, Johan B.

    2013-01-01

    Background: Daily physical activity (DPA) level is reduced in patients with COPD. The aim of this study was to investigate the association of DPA with functional and psychological variables in these patients. Methods: 155 COPD patients (102 males, median (IQR) age 62 years (54-69 years), predicted

  6. Physical activity in the elderly is associated with improved executive function and processing speed

    DEFF Research Database (Denmark)

    Frederiksen, Kristian Steen; Verdelho, Ana; Madureira, Sofia

    2015-01-01

    or dementia, were included. Multiple variable linear regression analysis with baseline MMSE, education, gender, age, stroke, diabetes and ARWMC rating as covariates revealed that physical activity was associated with better scores at baseline and 3-year follow-up for executive function (baseline: β: 0.39, 95...

  7. Temperamental activation and inhibition associated with autonomic function in preadolescents. The TRAILS study

    NARCIS (Netherlands)

    Dietrich, Andrea; Riese, Harriette; van Roon, Arie M.; Minderaa, Ruud B.; Oldehinkel, Albertine J.; Neeleman, Jan; Rosmalen, Judith G. M.

    We investigated the temperamental traits high-intensity pleasure (temperamental activation) and shyness (temperamental inhibition) in relation to autonomic function as measured by heart rate (HR), respiratory sinus arrhythmia (RSA), and baroreflex sensitivity (BRS) in 938 10-13-year-old

  8. Microbial functional diversity and enzymatic activity of soil degraded by sulphur mining reclaimed with various waste

    Science.gov (United States)

    Joniec, Jolanta; Frąc, Magdalena

    2017-10-01

    The aim of the study was to evaluate microbial functional diversity based on community level physiological profiling and β-glucosidase activity changes in soil degraded by sulphur mining and subjected to reclamation with various waste. The experiment was set up in the area of the former `Jeziórko' Sulphur Mine (Poland), on a soilless substrate with a particle size distribution of slightly loamy sand. The experimental variants included the application of post-flotation lime, sewage sludge and mineral wool. The analyses of soil samples included the assessment of the following microbiological indices: β-glucosidase activity and functional diversity average well color development and richness). The results indicate that sewage sludge did not exert a significant impact on the functional diversity of microorganisms present in the reclaimed soil. In turn, the application of other types of waste contributed to a significant increase in the parameters of total metabolic activity and functional diversity of the reclaimed soil. However, the temporal analysis of the metabolic profile of soil microorganisms demonstrated that a single application of waste did not yield a durable, stable metabolic profile in the reclaimed soil. Still, there was an increase in β-glucosidase activity, especially in objects treated with sewage sludge.

  9. An Analysis of Piecewise-Linear and Convex Value Functions for Active Perception POMDPs

    NARCIS (Netherlands)

    Satsangi, Y.; Whiteson, S.; Spaan, M.T.J.

    2015-01-01

    In active perception tasks, an agent aims to select actions that reduce its uncertainty about a hidden state. While partially observable Markov decision processes (POMDPs) are a natural model for such problems, reward functions that directly penalize uncertainty in the agent's belief can remove the

  10. High fat fed heart failure animals have enhanced mitochondrial function and acyl-coa dehydrogenase activities

    Science.gov (United States)

    We have previously shown that administration of high fat in heart failure (HF) increased mitochondrial respiration and did not alter left ventricular (LV) function. PPARalpha is a nuclear transcription factor that activates expression of genes involved in fatty acid uptake and utilization. We hypoth...

  11. Complementary three-dimensional quantitative structure-activity relationship modeling of binding affinity and functional potency

    DEFF Research Database (Denmark)

    Tosco, Paolo; Ahring, Philip K; Dyhring, Tino

    2009-01-01

    Complementary 3D-QSAR modeling of binding affinity and functional potency is proposed as a tool to pinpoint the molecular features of the ligands, and the corresponding amino acids in the receptor, responsible for high affinity binding vs those driving agonist behavior and receptor activation...

  12. Distributive Education--Marketing Functions. Kit No. 85. Instructor's Manual [and] Student Learning Activity Guide.

    Science.gov (United States)

    Kinard, Sandra

    An instructor's manual and student activity guide on marketing functions are provided in this set of prevocational education materials which focuses on the vocational area of distributive education. (This set of materials is one of ninety-two prevocational education sets arranged around a cluster of seven vocational offerings: agriculture, home…

  13. Differential Item Functioning Analysis of the 2003-04 NHANES Physical Activity Questionnaire

    Science.gov (United States)

    Gao, Yong; Zhu, Weimo

    2011-01-01

    Using differential item functioning (DIF) analyses, this study examined whether there were any DIF items in the National Health and Nutrition Examination Survey (NHANES) physical activity (PA) questionnaire. A subset of adult data from the 2003-04 NHANES study (n = 3,083) was used. PA items related to respondents' occupational, transportation,…

  14. Haemotoxic snake venoms : their functional activity, impact on snakebite victims and pharmaceutical promise

    NARCIS (Netherlands)

    Slagboom, Julien; Kool, Jeroen; Harrison, Robert A.; Casewell, Nicholas R.

    2017-01-01

    Snake venoms are mixtures of numerous proteinacious components that exert diverse functional activities on a variety of physiological targets. Because the toxic constituents found in venom vary from species to species, snakebite victims can present with a variety of life-threatening pathologies

  15. Microwave assisted bi-functional activation of -bromo-tert-alcohols

    Indian Academy of Sciences (India)

    unsaturated ketones in good yield is reported. The reaction of substrates with DMSO in 1:1 ratio (w/v) is promoted by ZnS in a solvent-free condition. A concurrent bi-functional activation of trans-vicinal bromo- and hydroxyl groups with ZnS is ...

  16. Statin Use and Functional Outcome after Tissue Plasminogen Activator Treatment in Acute Ischaemic Stroke

    NARCIS (Netherlands)

    Miedema, I; Uyttenboogaart, M; Koopman, K; De Keyser, J; Luijckx, G J

    Background: Preliminary findings suggest that statins may have a neuroprotective effect in patients with acute ischaemic stroke. This study investigated whether patients prior on statin therapy and treated with tissue plasminogen activator (tPA) for acute ischaemic stroke have a better functional

  17. Gain-Of-Function Mutational Activation of Human TRNA Synthetase Procytokine

    Energy Technology Data Exchange (ETDEWEB)

    Yang, X.L.; Kapoor, M.; Otero, F.J.; Slike, B.M.; Tsuruta, H.; Frausto, R.; Bates, A.; Ewalt, K.L.; Cheresh, D.A.; Schimmel, P.; /Scripps Res. Inst. /SLAC, SSRL

    2009-04-30

    Disease-causing mutations occur in genes for aminoacyl tRNA synthetases. That some mutations are dominant suggests a gain of function. Native tRNA synthetases, such as tyrosyl-tRNA synthetase (TyrRS) and tryptophanyl-tRNA synthetase, catalyze aminoacylation and are also procytokines that are activated by natural fragmentation. In principle, however, gain-of-function phenotypes could arise from mutational activation of synthetase procytokines. From crystal structure analysis, we hypothesized that a steric block of a critical Glu-Leu-Arg (ELR) motif in full-length TyrRS suppresses the cytokine activity of a natural fragment. To test this hypothesis, we attempted to uncover ELR in the procytokine by mutating a conserved tyrosine (Y341) that tethers ELR. Site-specific proteolytic cleavage and small-angle X-ray scattering established subtle opening of the structure by the mutation. Strikingly, four different assays demonstrated mutational activation of cytokine functions. The results prove the possibilities for constitutive gain-of-function mutations in tRNA synthetases.

  18. Control interfaces to actively support the arm function of men with Duchenne Muscular Dystrophy

    NARCIS (Netherlands)

    Lobo Prat, J.

    2016-01-01

    Adults with DMD can benefit from active arm supports that augment their residual functional capabilities. However, intuitively controlled and fully actuated arm supports are currently not commercially available and adults with DMD are limited to use external robotic arms which contribute to the

  19. Kinetics of the esterification of active pharmaceutical ingredients containing carboxylic Acid functionality in polyethylene glycol

    DEFF Research Database (Denmark)

    Schou-Pedersen, Anne Marie V; Hansen, Steen Honoré; Moesgaard, Birthe

    2014-01-01

    reactions. In this study, kinetics of two active pharmaceutical ingredients, cetirizine and indomethacin possessing carboxylic acid functionality, has been studied in PEG 400 and PEG 1000 at 50°C, 60°C, 70°C, and 80°C. HPLC-UV was applied for the determination of concentrations in the kinetic studies...

  20. Activation of resistance arteries with endothelin-1: From vasoconstriction to functional adaptation and remodeling

    NARCIS (Netherlands)

    Bakker, Erik N. T. P.; Buus, Carsten L.; VanBavel, Ed; Mulvany, Michael J.

    2004-01-01

    Remodeling of resistance arteries is a key feature in hypertension. We studied the transition of vasoconstriction to remodeling in isolated rat skeletal muscle arterioles. Arterioles activated with 10 nM endothelin-1 showed functional adaptation when kept at low distension in a wire myograph setup,

  1. Functional level, physical activity and wellbeing in nursing home residents in three Nordic countries

    DEFF Research Database (Denmark)

    Grönstedt, Helena; Hellström, Karin; Bergland, Astrid

    2011-01-01

    The main aim of this study was to describe physical and cognitive function and wellbeing among nursing home residents in three Nordic countries. A second aim was to compare groups of differing ages, levels of dependency in daily life activities (ADL), degree of fall-related self-efficacy, wellbeing...

  2. Fast Back-Propagation Learning Using Steep Activation Functions and Automatic Weight

    Science.gov (United States)

    Tai-Hoon Cho; Richard W. Conners; Philip A. Araman

    1992-01-01

    In this paper, several back-propagation (BP) learning speed-up algorithms that employ the ãgainä parameter, i.e., steepness of the activation function, are examined. Simulations will show that increasing the gain seemingly increases the speed of convergence and that these algorithms can converge faster than the standard BP learning algorithm on some problems. However,...

  3. Measurement of abdominal muscle thickness using M-mode ultrasound imaging during functional activities.

    Science.gov (United States)

    Bunce, Steve M; Hough, Alan D; Moore, Ann P

    2004-02-01

    Ultrasound imaging has been previously utilized in the measurement of muscle thickness and cross-sectional area in research studies, and advocated as a clinical biofeedback tool in the rehabilitation of transversus abdominis function following episodes of low back pain. This paper describes how the thickness of the abdominal muscles can be quantified with a new measurement technique using M-mode ultrasound. The technique uses a custom-made transducer holder that facilitates measurement of muscle thickness changes during functional activity. Limitations of the technique and potential future applications are discussed. The M-mode ultrasound technique may provide an effective method for the non-invasive measurement of abdominal muscle thickness during functional activities.

  4. Absolute exponential stability of recurrent neural networks with Lipschitz-continuous activation functions and time delays.

    Science.gov (United States)

    Cao, Jinde; Wang, Jun

    2004-04-01

    This paper investigates the absolute exponential stability of a general class of delayed neural networks, which require the activation functions to be partially Lipschitz continuous and monotone nondecreasing only, but not necessarily differentiable or bounded. Three new sufficient conditions are derived to ascertain whether or not the equilibrium points of the delayed neural networks with additively diagonally stable interconnection matrices are absolutely exponentially stable by using delay Halanay-type inequality and Lyapunov function. The stability criteria are also suitable for delayed optimization neural networks and delayed cellular neural networks whose activation functions are often nondifferentiable or unbounded. The results herein answer a question: if a neural network without any delay is absolutely exponentially stable, then under what additional conditions, the neural networks with delay is also absolutely exponentially stable.

  5. Nonlinear dynamic response and active vibration control for piezoelectric functionally graded plate

    Science.gov (United States)

    Yiqi, Mao; Yiming, Fu

    2010-05-01

    The nonlinear dynamic response and active vibration control of the piezoelectric functionally graded plate are analyzed in this paper. Based on higher-order shear plate theory and elastic piezoelectric theory, the nonlinear geometric and constitutive relations of the piezoelectric functionally graded plate are established, and then the nonlinear motion equations of the piezoelectric functionally graded plate are obtained through Hamilton's variational principle. The nonlinear active vibration control of the structure is carried out with adoption of the negative velocity feedback control algorithm. By applying finite difference method, the whole problem is solved by using iterative method synthetically. In numerical examples, the effects of mechanical load, electric load, the volume fraction and the geometric parameters on the dynamic response and vibration control of the piezoelectric FGM plate are investigated.

  6. Relations between Recent Past Leisure Activities with Risks of Dementia and Cognitive Functions after Stroke.

    Science.gov (United States)

    Wong, Adrian; Lau, Alexander Y L; Lo, Eugene; Tang, Michael; Wang, Zhaolu; Liu, Wenyan; Tanner, Nicole; Chau, Natalie; Law, Lorraine; Shi, Lin; Chu, Winnie C W; Yang, Jie; Xiong, Yun-Yun; Lam, Bonnie Y K; Au, Lisa; Chan, Anne Y Y; Soo, Yannie; Leung, Thomas W H; Wong, Lawrence K S; Lam, Linda C W; Mok, Vincent C T

    2016-01-01

    Leisure activity participation has been shown to lower risks of cognitive decline in non-stroke populations. However, effects of leisure activities participation upon cognitive functions and risk of dementia after stroke are unclear. The purpose of this study is to examine the effects of recent past leisure activities participation upon cognitive functions and risk of incident dementia after stroke. Hospital-based, retrospective cohort study. 88 of 1,013 patients with stroke or TIA having no prestroke dementia were diagnosed to have incident poststroke dementia (PSD) 3-6 months after stroke. Regular participation (≥3 times per week) in intellectual, recreational, social and physical activities over the year before the index stroke was retrospectively recorded at 3-6 months after stroke. Logistic regression analyses showed that regular participation in intellectual (RR 0.36, 95%CI 0.20-0.63) and stretching & toning physical exercise (0.37, 0.21-0.64) was significantly associated with a reduced risk of PSD after controlling for age, education, prestroke cognitive decline, stroke subtype, prior strokes and chronic brain changes including white matter changes, old infarcts and global atrophy. Results were similar in patients with past strokes in unadjusted models. Participation in increased number of activities in general (r = 0.41, pleisure activities was associated with better poststroke cognitive performance. Findings of this retrospective cohort study call for studies of activity intervention for prevention of cognitive decline in individuals at elevated risk of stroke.

  7. Carbohydrate-functionalized nanovaccines preserve HIV-1 antigen stability and activate antigen presenting cells

    Science.gov (United States)

    Vela Ramirez, J.E.; Roychoudhury, R.; Habte, H.H.; Cho, M. W.; Pohl, N. L. B.; Narasimhan, B.

    2015-01-01

    The functionalization of polymeric nanoparticles with ligands that target specific receptors on immune cells offers the opportunity to tailor adjuvant properties by conferring pathogen mimicking attributes to the particles. Polyanhydride nanoparticles are promising vaccine adjuvants with desirable characteristics such as immunomodulation, sustained antigen release, activation of antigen presenting cells, and stabilization of protein antigens. These capabilities can be exploited to design nanovaccines against viral pathogens, such as HIV-1, due to the important role of dendritic cells and macrophages in viral spread. In this work, an optimized process was developed for carbohydrate functionalization of HIV-1 antigen-loaded polyanhydride nanoparticles. The carbohydrate-functionalized nanoparticles preserved antigenic properties upon release and also enabled sustained antigen release kinetics. Particle internalization was observed to be chemistry-dependent with positively charged nanoparticles being taken up more efficiently by dendritic cells. Up-regulation of the activation makers CD40 and CD206 was demonstrated with carboxymethyl-α-d-mannopyranosyl-(1,2)-d-mannopyranoside functionalized nanoparticles. The secretion of the cytokines IL-6 and TNF-α was shown to be chemistry-dependent upon stimulation with carbohydrate-functionalized nanoparticles. These results offer important new insights upon the interactions between carbohydrate-functionalized nanoparticles and antigen presenting cells and provide foundational information for the rational design of targeted nanovaccines against HIV-1. PMID:25068589

  8. Dissection of Functional Residues in Receptor Activity-Modifying Proteins Through Phylogenetic and Statistical Analyses

    Directory of Open Access Journals (Sweden)

    Alfonso Benítez-Páez

    2008-01-01

    Full Text Available Type I and type-II functional divergences have been stated to highlight specific residues carrying out differential functions in evolutionary-divergent protein clusters from a single common ancestor. Briefly, type I analysis is based on residue constraints reflecting a gain of function just in one cluster of an entire family of proteins; while the type-II approach is based on residue constraints showing a different chemical nature in every cluster of a protein family. This last evidence is understood as differential functionality among clusters. The Receptor Activity-Modifying Proteins constitute a family characterized by its paralogous distribution in vertebrates. They are known as G-Protein Coupled Receptor modulators. Although several studies have determined their involvement in ligand binding, specificity, and enhancement of signal transduction, the responsible residues supporting those functions are unclear. Using different bioinformatic approaches, we predicted residues involved in different RAMP functional tasks. Many residues localized in an extracellular coil of RAMP proteins were predicted to be under functional divergence suggesting a gain of function in their respective proteins. Interestingly, the transmembrane region also showed important results for residues playing relevant roles where most of them showed a biased distribution on the structure. A relevant role was conferred by the enrichment of type-II residues observed in their sequences. We show a collection of residues explaining possible gain of function and differential functionality in RAMP proteins. These residues are still experimentally unexplored with regards to functionality. Finally, an evolutionary history could be discerned. Mainly, the RAMP2 cluster has evolved in a higher manner than other RAMP clusters. However, a deacceleration in the aminoacid substitution rate of RAMP2 was observed in mammals. Such effect could be caused by the co-evolution of ligands and

  9. Physical activity and motor function in children and adolescents with neuromuscular disorders.

    Science.gov (United States)

    Holtebekk, M Elizabeth; Berntsen, Sveinung; Rasmussen, Magnhild; Jahnsen, Reidun B

    2013-01-01

    To determine physical function and activity level in children and adolescents with neuromuscular disorders. Seventeen children and adolescents aged 10 to 18 years with neuromuscular disorders who were ambulatory participated. Physical function was measured using the Hammersmith Motor Ability Scale and the Six-Minute Walk Test. Physical activity (PA) level was measured using the SenseWear Armband activity monitor. Activities were recorded using a questionnaire. Results were compared with previous data published for peers who are healthy and public recommendations. Hammersmith Motor Ability Scale scores were lower than normal values. Results of the Six-Minute Walk Test were considerably lower than results for peers who are healthy. Time in PA and the number of steps were considerably lower on holidays and slightly lower on weekdays compared with the values for peers who are healthy. No vigorous activity was registered. The participants had lower physical function and PA levels than peers who are healthy. The small, heterogeneous sample makes generalizations challenging and multicenter studies are recommended.

  10. The dead seed coat functions as a long-term storage for active hydrolytic enzymes

    Science.gov (United States)

    Raviv, Buzi; Aghajanyan, Lusine; Granot, Gila; Makover, Vardit; Frenkel, Omer; Gutterman, Yitzchak

    2017-01-01

    Seed development culminates in programmed cell death (PCD) and hardening of organs enclosing the embryo (e.g., pericarp, seed coat) providing essentially a physical shield for protection during storage in the soil. We examined the proposal that dead organs enclosing embryos are unique entities that store and release upon hydration active proteins that might increase seed persistence in soil, germination and seedling establishment. Proteome analyses of dead seed coats of Brassicaceae species revealed hundreds of proteins being stored in the seed coat and released upon hydration, many are stress-associated proteins such as nucleases, proteases and chitinases. Functional analysis revealed that dead seed coats function as long-term storage for multiple active hydrolytic enzymes (e.g., nucleases) that can persist in active forms for decades. Substances released from the dead seed coat of the annual desert plant Anastatica hierochuntica displayed strong antimicrobial activity. Our data highlighted a previously unrecognized feature of dead organs enclosing embryos (e.g., seed coat) functioning not only as a physical shield for embryo protection but also as a long-term storage for active proteins and other substances that are released upon hydration to the “seedsphere” and could contribute to seed persistence in the soil, germination and seedling establishment. PMID:28700755

  11. Influence of grain activation conditions on functional characteristics of brown rice flour.

    Science.gov (United States)

    Singh, Arashdeep; Sharma, Savita; Singh, Baljit

    2017-09-01

    Grain activation is a natural processing technique that can be used to produce modified flours without chemical modification. Functional characteristics of brown rice flour as influenced by grain activation time and temperatures were investigated. Germination temperatures at 25 ℃, 30 ℃ and 35 ℃ and time for 12, 24, 36 and 48 h significantly influenced the functional properties of flour with modification of starch, protein and high enzymatic activity. Significant decrease in the bulk density, water absorption and swelling power of brown rice flour was observed in comparison to non-germinated flour. Gel consistency and oil absorption capacity of brown rice flour increased as the grain activation time and temperature were increased. Native flour had lowest emulsion and foaming properties, while increase in grain activation time and temperature enhanced the emulsifying and foaming properties of flour. Paste clarity of native flour was 54% which was reduced to 25.17%; however, increase in germination time and temperature increased the % synersis values of germinated flour. Native flour had least gelation concentration of 12% which increased to 25% after 48 h of germination at 35 ℃. Overall, germination can be used as a natural way to modify the functional properties of brown rice flours for their utilization in variety food products.

  12. Regulation of myelin genes implicated in psychiatric disorders by functional activity in axons

    Directory of Open Access Journals (Sweden)

    Philip R Lee

    2009-06-01

    Full Text Available Myelination is a highly dynamic process that continues well into adulthood in humans. Several recent gene expression studies have found abnormal expression of genes involved in myelination in the prefrontal cortex of brains from patients with schizophrenia and other psychiatric illnesses. Defects in myelination could contribute to the pathophysiology of psychiatric illness by impairing information processing as a consequence of altered impulse conduction velocity and synchrony between cortical regions carrying out higher level cognitive functions. Myelination can be altered by impulse activity in axons and by environmental experience. Psychiatric illness is treated by psychotherapy, behavioral modification, and drugs affecting neurotransmission, raising the possibility that myelinating glia may not only contribute to such disorders, but that activity-dependent effects on myelinating glia could provide one of the cellular mechanisms contributing to the therapeutic effects of these treatments. This review examines evidence showing that genes and gene networks important for myelination can be regulated by functional activity in axons.

  13. Hypothalamus-pituitary-thyroid axis activity and function of cardiac muscle in energy deficit

    Directory of Open Access Journals (Sweden)

    Katarzyna Lachowicz

    2017-12-01

    Full Text Available Frequently repeated statement that energy restriction is a factor that improves cardiovascular system function seems to be not fully truth. Low energy intake modifies the hypothalamus-pituitary-thyroid axis activity and thyroid hormone peripheral metabolism. Thyroid hormones, as modulators of the expression and activity of many cardiomyocyte proteins, control heart function. Decreased thyroid hormone levels and their disturbanced conversion and action result in alternation of cardiac remodeling, disorder of calcium homeostasis and diminish myocardial contractility. This review provides a summary of the current state of knowledge about the mechanisms of energy restriction effects on thyroidal axis activity, thyroid hormone peripheral metabolism and action in target tissues, especially in cardiac myocytes. We also showed the existence of energy restriction-thyroid-heart pathway.

  14. Inhibition of water activated by far infrared functional ceramics on proliferation of hepatoma cells.

    Science.gov (United States)

    Zhang, Dongmei; Liang, Jinsheng; Ding, Yan; Meng, Junping; Zhang, Guangchuan

    2014-05-01

    Rare earth (RE)/tourmaline composite materials prepared by the precipitation method are added to the ceramic raw materials at a certain percentage and sintered into RE functional ceramics with high far infrared emission features. Then the far infrared functional ceramics are used to interact with water. The influence of the ceramics on the physical parameters of water is investigated, and the effect of the activated water on the growth of Bel-7402 hepatoma cells cultured in vitro is further studied. The results indicate that, compared with the raw water, the water activated by the ceramics can inhibit the proliferation of hepatoma cells, with statistical probability P ceramics has a higher concentration of H+, which decreases the potential difference across the cell membrane to release the apoptosis inducing factor (AIF). After entering the cells, the activated water stimulates the mitochondria to produce immune substances that lead tumor cells to apoptosis.

  15. Molecular Characteristics and Biological Functions of Surface-Active and Surfactant Proteins.

    Science.gov (United States)

    Sunde, Margaret; Pham, Chi L L; Kwan, Ann H

    2017-06-20

    Many critical biological processes take place at hydrophobic:hydrophilic interfaces, and a wide range of organisms produce surface-active proteins and peptides that reduce surface and interfacial tension and mediate growth and development at these boundaries. Microorganisms produce both small lipid-associated peptides and amphipathic proteins that allow growth across water:air boundaries, attachment to surfaces, predation, and improved bioavailability of hydrophobic substrates. Higher-order organisms produce surface-active proteins with a wide variety of functions, including the provision of protective foam environments for vulnerable reproductive stages, evaporative cooling, and gas exchange across airway membranes. In general, the biological functions supported by these diverse polypeptides require them to have an amphipathic nature, and this is achieved by a diverse range of molecular structures, with some proteins undergoing significant conformational change or intermolecular association to generate the structures that are surface active.

  16. In vitro culture of functionally active buffalo hepatocytes isolated by using a simplified manual perfusion method.

    Directory of Open Access Journals (Sweden)

    Santanu Panda

    Full Text Available In farm animals, there is no suitable cell line available to understand liver-specific functions. This has limited our understanding of liver function and metabolism in farm animals. Culturing and maintenance of functionally active hepatocytes is difficult, since they survive no more than few days. Establishing primary culture of hepatocytes can help in studying cellular metabolism, drug toxicity, hepatocyte specific gene function and regulation. Here we provide a simple in vitro method for isolation and short-term culture of functionally active buffalo hepatocytes.Buffalo hepatocytes were isolated from caudate lobes by using manual enzymatic perfusion and mechanical disruption of liver tissue. Hepatocyte yield was (5.3 ± 0.66×107 cells per gram of liver tissue with a viability of 82.3 ± 3.5%. Freshly isolated hepatocytes were spherical with well contrasted border. After 24 hours of seeding onto fibroblast feeder layer and different extracellular matrices like dry collagen, matrigel and sandwich collagen coated plates, hepatocytes formed confluent monolayer with frequent clusters. Cultured hepatocytes exhibited typical cuboidal and polygonal shape with restored cellular polarity. Cells expressed hepatocyte-specific marker genes or proteins like albumin, hepatocyte nuclear factor 4α, glucose-6-phosphatase, tyrosine aminotransferase, cytochromes, cytokeratin and α1-antitrypsin. Hepatocytes could be immunostained with anti-cytokeratins, anti-albumin and anti α1-antitrypsin antibodies. Abundant lipid droplets were detected in the cytosol of hepatocytes using oil red stain. In vitro cultured hepatocytes could be grown for five days and maintained for up to nine days on buffalo skin fibroblast feeder layer. Cultured hepatocytes were viable for functional studies.We developed a convenient and cost effective technique for hepatocytes isolation for short-term culture that exhibited morphological and functional characteristics of active hepatocytes

  17. EFFECTS OF LONG-TERM PHYSICAL ACTIVITY ON CARDIAC STRUCTURE AND FUNCTION: A TWIN STUDY

    Directory of Open Access Journals (Sweden)

    Urho M.Kujala

    2009-12-01

    Full Text Available Previous studies have shown that athletic training or other physical activity causes structural and functional adaptations in the heart, but less is known how long-term physical activity affects heart when genetic liability and childhood environment are taken into account. The aim of this study was to investigate the effects of long-term physical activity vs. inactivity on cardiac structure and function in twin pairs discordant for physical activity for 32 years. Twelve same-sex twin pairs (five monozygotic and seven dizygotic, 50-67 years were studied as a part of the TWINACTIVE study. Discordance in physical activity was initially determined in 1975 and it remained significant throughout the follow-up. At the end of the follow-up in 2007, resting echocardiographic and electrocardiographic measurements were performed. During the follow-up period, the active co-twins were on average 8.2 (SD 4.0 MET hours/day more active than their inactive co-twins (p < 0.001. At the end of the follow-up, resting heart rate was lower in the active than inactive co-twins [59 (SD 5 vs. 68 (SD 10 bpm, p=0.03]. The heart rate-corrected QT interval was similar between the co-twins. Also, there was a tendency for left ventricular mass per body weight to be greater and T wave amplitude in lead II to be higher in the active co-twins (18% and 15%, respectively, p=0.08 for both. Similar trends were found for both monozygotic and dizygotic twin pairs. In conclusion, the main adaptation to long- term physical activity is lowered resting heart rate, even after partially or fully controlling for genetic liability and childhood environment

  18. Linking Activity and Function to Ecosystem Dynamics in a Coastal Bacterioplankton Community

    Directory of Open Access Journals (Sweden)

    Scott Michael Gifford

    2014-04-01

    Full Text Available For bacterial communities containing hundreds to thousands of distinct populations, connecting functional processes and environmental dynamics at high taxonomic resolution has remained challenging. Here we use the expression of ribosomal proteins (%RP as a proxy for in situ activity of 200 taxa within 20 metatranscriptomic samples in a coastal ocean time series encompassing both seasonal variability and diel dynamics. %RP patterns grouped the taxa into seven activity clusters with distinct profiles in functional gene expression and correlations with environmental gradients. Clusters 1-3 had their highest potential activity in the winter and fall, and included some of the most active taxa, while Clusters 4-7 had their highest potential activity in the spring and summer. Cluster 1 taxa were characterized by gene expression for motility and complex carbohydrate degradation (dominated by Gammaproteobacteria and Bacteroidetes, and Cluster 2 taxa by transcription of genes for amino acid and aromatic compound metabolism and aerobic anoxygenic phototrophy (Roseobacter. Other activity clusters were enriched in transcripts for proteorhodopsin and methylotrophy (Cluster 4; SAR11 and methylotrophs, photosynthesis and attachment (Clusters 5 and 7; Synechococcus, picoeukaryotes, Verucomicrobia, and Planctomycetes, and sulfur oxidation (Cluster 7; Gammaproteobacteria. The seasonal patterns in activity were overlain, and sometimes obscured, by large differences in %RP over shorter day-night timescales. Seventy-eight taxa, many of them heterotrophs, had a higher %RP activity index during the day than night, indicating strong diel activity at this coastal site. Emerging from these taxonomically- and time-resolved estimates of in situ microbial activity are predictions of specific ecological groupings of microbial taxa in a dynamic coastal environment.

  19. Effect of Regular Aerobic Activity in Young Healthy Athletes on Profile of Endothelial Function and Platelet Activity

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    Katarzyna Podgórska

    2017-01-01

    Full Text Available The aim of the study was to assess the impact of regular professional sports activity on the endothelial and platelet function in young men. The studied group were 79 young men (18–40 y, 25 athletes and 54 without any regular physical activity. The nitric oxide (NO metabolic pathway intermediates, oxidative stress markers, mediators of inflammation, and platelet aggregation were measured. Flow mediated dilation (FMD was studied before and after intravenous 16,0 g L-arginine infusion, which was repeated after oral administration of acetylsalicylic acid (ASA-75 mg/day for 4 days. Both groups had similar demographic characteristics. In the athletes, there was significantly higher hsCRP level, better serum lipid profile, and lower pulse pressure. Greater baseline FMD in athletes and in response to L-arginine disappeared following ASA treatment. There were no differences in the levels of the NO pathway metabolites. The control group was characterized by higher PAI-1 following ASA treatment and sICAM-1 both at baseline and after ASA, but no differences in MDA and 6-keto-PGF-1 alpha and platelet aggregation were noted. Regular professional physical activity modulates endothelial but not platelet function and may thus exert an effect on overall cardiovascular risk.

  20. Additional impact on muscle function when treating active rheumatoid arthritis patients with high alphacalcidol doses

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    Simić-Pašalić Katarina

    2017-01-01

    Full Text Available Background/Aim. Hormone D (vitamin D plays an important role in immunoregulation and musculoskeletal metabolism. The aim of this study was to assess the impact of alfacalcidol (ILD3 or prednisone use on muscle function and disease activity in active rheumatoid arthritis (RA. Methods. The study included 67 RA patients with the active disease, disease activity score (DAS28 > 3.2, on the highest tolerable methotrexate (MTX dose during last 3 months. Data collected were: DAS 28, muscle function tests [chair rising test (CRT timed up and go (TUG, 6 minutes walk (6MWT, tandem walk (TW], efficacy and safety laboratory tests. At enrollment, patients were randomly assigned to three-month supplementation with 1 μg (group A1 or 2 μg (group A2 or 3 μg (group A3 of 1αD3 daily or prednisone (group C 20 mg daily, for the first month and 10 mg afterward, in addition to MTX. Results. After the treatment, we found highly significantly reduced disease activity in all four treatment arms (DAS28 p < 0.01. 1αD3 2 μg (A2 group, n = 19 treated patients significantly improved muscle function (TUG, 6MWT, while 1αD3 3 μg treated (A3, n = 16 improved 6MWT (p < 0.05, and CRT (p < 0.01. Serum 25(OHD3 significantly decreased in the group C (p < 0.01, in contrast to its changes obtained in alfacalcidol treated ones. Conclusion. 1αD3 2 μg and 3 μg daily is as effective as prednisone (mean 13.3 mg daily in RA activity control and also has the additional favorable impact on muscle function.

  1. Soil microbial activity in hydromorphic-subaqueous ecosystems: processes and functional biodiveristy

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    Ruxandra Papp

    2015-12-01

    Full Text Available The hydromorphic and subaqueous soils have largely been overlooked on their pedogenic concepts or in soil C accounting studies considering their phisico-chemical properties. Conversely, little attention has been paid to the microbial activity playing a key role in regulating the biogeochemical cycle of elements. The aim of the study was to evaluate biological properties such as enzyme activities and the functional diversity of soil microbial population as bio- indicators, sensitive to processes affected by the water shallow. Eight soil profiles were opened along two transects: 1 a-a’ North and 2 b-b' South, in a dune ecosystem of the Adriatic coast, Ravenna (Italy. The soil chemical and biochemical properties were determined. In particular, soil enzyme activities and soil induced respiration were measured using the microplates technique in order to assess the microbial functional diversity. The soil biochemical properties such as the potential enzyme activities and microbial induced respiration, as well as microbial functional diversity were sensitive indicators to study hydromorphic and subaqueous soils. A general reduction of hydrolytic enzyme activities was observed in subaqueous soil with respect to hydromorphic one. Moreover, the endopedon of subaqueous soils showed a lower microbial functional diversity than hydromorphic one. In this study the ratio of enzyme activities involved in C to S cycles (SEIC/Aryl as well as the C:S ratio showed a marked reduction in the subaqueous with respect to hydromorphic soils. In conclusion, in a coastal area the C and S biogeochemical cycles, in the hydromorphic and subaqueous soils, may depend on freshwater and saltwater interface equilibrium.

  2. The Antifungal Activity of Functionalized Chitin Nanocrystals in Poly (Lactid Acid Films

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    Asier M. Salaberria

    2017-05-01

    Full Text Available As, in the market, poly (lactic acid (PLA is the most used polymer as an alternative to conventional plastics, and as functionalized chitin nanocrystals (CHNC can provide structural and bioactive properties, their combination sounds promising in the preparation of functional nanocomposite films for sustainable packaging. Chitin nanocrystals were successfully modified via acylation using anhydride acetic and dodecanoyl chloride acid to improve their compatibility with the matrix, PLA. The nanocomposite films were prepared by extrusion/compression approach using different concentrations of both sets of functionalized CHNC. This investigation brings forward that both sets of modified CHNC act as functional agents, i.e., they slightly improved the hydrophobic character of the PLA nanocomposite films, and, very importantly, they also enhanced their antifungal activity. Nonetheless, the nanocomposite films prepared with the CHNC modified with dodecanoyl chloride acid presented the best properties.

  3. Physical activity and cognitive function in individuals over 60 years of age: a systematic review

    Directory of Open Access Journals (Sweden)

    Carvalho A

    2014-04-01

    Full Text Available Ashley Carvalho,1,2 Irene Maeve Rea,2 Tanyalak Parimon,3,4 Barry J Cusack3,51Department of Public Health, 2School of Medicine, Dentistry and Biomedical Science, Queen’s University Belfast, Northern Ireland, UK; 3Research and Development Service, Veterans Affairs Medical Center, Boise, ID, USA; 4Division of Pulmonary and Critical Care Medicine, 5Division of Gerontology and Geriatric Medicine, Department of Medicine, University of Washington, Seattle, WA, USABackground: It is unclear whether physical activity in later life is beneficial for maintenance of cognitive function. We performed a systematic review examining the effects of exercise on cognitive function in older individuals, and present possible mechanisms whereby physical activity may improve cognition.Methods: Sources consisted of PubMed, Medline, CINAHL, the Cochrane Controlled Trials Register, and the University of Washington, School of Medicine Library Database, with a search conducted on August 15, 2012 for publications limited to the English language starting January 1, 2000. Randomized controlled trials including at least 30 participants and lasting at least 6 months, and all observational studies including a minimum of 100 participants for one year, were evaluated. All subjects included were at least 60 years of age.Results: Twenty-seven studies met the inclusion criteria. Twenty-six studies reported a positive correlation between physical activity and maintenance or enhancement of cognitive function. Five studies reported a dose-response relationship between physical activity and cognition. One study showed a nonsignificant correlation.Conclusion: The preponderance of evidence suggests that physical activity is beneficial for cognitive function in the elderly. However, the majority of the evidence is of medium quality with a moderate risk of bias. Larger randomized controlled trials are needed to clarify the association between exercise and cognitive function and to determine

  4. Physical activity unveils the relationship between mitochondrial energetics, muscle quality, and physical function in older adults.

    Science.gov (United States)

    Distefano, Giovanna; Standley, Robert A; Zhang, Xiaolei; Carnero, Elvis A; Yi, Fanchao; Cornnell, Heather H; Coen, Paul M

    2018-01-24

    The concept of mitochondrial dysfunction in ageing muscle is highly controversial. In addition, emerging evidence suggests that reduced muscle oxidative capacity and efficiency underlie the aetiology of mobility loss in older adults. Here, we hypothesized that studying well-phenotyped older cohorts across a wide range of physical activity would unveil a range of mitochondrial function in skeletal muscle and in turn allow us to more clearly examine the impact of age per se on mitochondrial energetics. This also enabled us to more clearly define the relationships between mitochondrial energetics and muscle lipid content with clinically relevant assessments of muscle and physical function. Thirty-nine volunteers were recruited to the following study groups: young active (YA, n = 2 women/8 men, age = 31.2 ± 5.4 years), older active (OA, n = 2 women/8 men, age = 67.5 ± 2.7 years), and older sedentary (OS, n = 8 women/11 men, age = 70.7 ± 4.7 years). Participants completed a graded exercise test to determine fitness (VO 2 peak), a submaximal exercise test to determine exercise efficiency, and daily physical activity was recorded using a tri-axial armband accelerometer. Mitochondrial energetics were determined by (i) 31 P magnetic resonance spectroscopy and (ii) respirometry of fibre bundles from vastus lateralis biopsies. Quadriceps function was assessed by isokinetic dynamometry and physical function by the short physical performance battery and stair climb test. Daily physical activity energy expenditure was significantly lower in OS, compared with YA and OA groups. Despite fitness being higher in YA compared with OA and OS, mitochondrial respiration, maximum mitochondrial capacity, Maximal ATP production/Oxygen consumption (P/O) ratio, and exercise efficiency were similar in YA and OA groups and were significantly lower in OS. P/O ratio was correlated with exercise efficiency. Time to complete the stair climb and repeated chair stand tests were

  5. Characterization of functional microorganism groups and substrate in activated sludge and wastewater by AUR, NUR and OUR

    DEFF Research Database (Denmark)

    Kristensen, G. Holm; Jørgensen, P. Elberg; Henze, Mogens

    1992-01-01

    Activated sludge functional microorganism groups: nitrifiers, denitrifiers and heterotrophs, were characterized through determinations of maximum specific utilization rates of ammonia (AUR) nitrate (NUR) and oxygen (OUR). Characterizations of the functional groups were done on activated sludges f...... that hydrolysis of activated sludge COD takes place with the same rate under anoxic and aerobic process conditions....

  6. Determination of the activity of maleimide-functionalized phospholipids during preparation of liposomes.

    Science.gov (United States)

    Oswald, Mira; Geissler, Simon; Goepferich, Achim

    2016-11-30

    Numerous examples exist in the literature for the use of maleimide-thiol-reactions in the area of functionalized nanoparticles. Although the hydrolysis tendency of maleimides is well-known, qualitative and quantitative information on the stability and reactivity of maleimide groups during preparation and in final formulations are missing. This is surprising, since hydrolysis of maleimides prevents nanoparticle functionalization and results in an increase of negative surface charge due to the hydrolysis product maleic acid. In this study we investigated the stability of 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[maleimide-2000] (DSPE-PEG 2000 -Mal) during the preparation of liposomes via two common preparation methods, which can be distinguished by the insertion of DSPE-PEG 2000 -Mal during or after the liposome formation process (pre-insertion and post-insertion process). The liposomes prepared by the pre-insertion method had 63% active maleimide groups remaining on their surface. The activity decreased dramatically during the purification process down to 32%. The preparation by post-insertion showed minimal effects with regard to maleimide activity. 76% of maleimide groups were active and therefore available for coupling reaction. By identifying active maleimide groups on the surface of the final formulations, the presented work revealed the dramatic impact of preparation methods on the activity of maleimide groups. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. Platelet activation, function, and reactivity in atherosclerotic carotid artery stenosis: a systematic review of the literature.

    LENUS (Irish Health Repository)

    Kinsella, J A

    2012-09-27

    An important proportion of transient ischemic attack or ischemic stroke is attributable to moderate or severe (50-99%) atherosclerotic carotid stenosis or occlusion. Platelet biomarkers have the potential to improve our understanding of the pathogenesis of vascular events in this patient population. A detailed systematic review was performed to collate all available data on ex vivo platelet activation and platelet function\\/reactivity in patients with carotid stenosis. Two hundred thirteen potentially relevant articles were initially identified; 26 manuscripts met criteria for inclusion in this systematic review. There was no consistent evidence of clinically informative data from urinary or soluble blood markers of platelet activation in patients with symptomatic moderate or severe carotid stenosis who might be considered suitable for carotid intervention. Data from flow cytometry studies revealed evidence of excessive platelet activation in patients in the early, sub-acute, or late phases after transient ischemic attack or stroke in association with moderate or severe carotid stenosis and in asymptomatic moderate or severe carotid stenosis compared with controls. Furthermore, pilot data suggest that platelet activation may be increased in recently symptomatic than in asymptomatic severe carotid stenosis. Excessive platelet activation and platelet hyperreactivity may play a role in the pathogenesis of first or subsequent transient ischemic attack or stroke in patients with moderate or severe carotid stenosis. Larger longitudinal studies assessing platelet activation status with flow cytometry and platelet function\\/reactivity in symptomatic vs. asymptomatic carotid stenosis are warranted to improve our understanding of the mechanisms responsible for transient ischemic attack or stroke.

  8. PCNA function in the activation and strand direction of MutLα endonuclease in mismatch repair

    Science.gov (United States)

    Pluciennik, Anna; Dzantiev, Leonid; Iyer, Ravi R.; Constantin, Nicoleta; Kadyrov, Farid A.; Modrich, Paul

    2010-01-01

    MutLα (MLH1–PMS2) is a latent endonuclease that is activated in a mismatch-, MutSα-, proliferating cell nuclear antigen (PCNA)-, replication factor C (RFC)-, and ATP-dependent manner, with nuclease action directed to the heteroduplex strand that contains a preexisting break. RFC depletion experiments and use of linear DNAs indicate that RFC function in endonuclease activation is limited to PCNA loading. Whereas nicked circular heteroduplex DNA is a good substrate for PCNA loading and for endonuclease activation on the incised strand, covalently closed, relaxed circular DNA is a poor substrate for both reactions. However, covalently closed supercoiled or bubble-containing relaxed heteroduplexes, which do support PCNA loading, also support MutLα activation, but in this case cleavage strand bias is largely abolished. Based on these findings we suggest that PCNA has two roles in MutLα function: The clamp is required for endonuclease activation, an effect that apparently involves interaction of the two proteins, and by virtue of its loading orientation, PCNA determines the strand direction of MutLα incision. These results also provide a potential mechanism for activation of mismatch repair on nonreplicating DNA, an effect that may have implications for the somatic phase of triplet repeat expansion. PMID:20713735

  9. The Relationship Between Reminiscence Functions, Optimism, Depressive Symptoms, Physical Activity, and Pain in Older Adults.

    Science.gov (United States)

    McDonald, Deborah Dillon; Shellman, Juliette M; Graham, Lindsey; Harrison, Lisa

    2016-09-01

    The study purpose was to examine the association between reminiscence functions, optimism, depressive symptoms, physical activity, and pain in older adults with chronic lower extremity osteoarthritis pain. One hundred ninety-five community-dwelling adults were interviewed using the Modified Reminiscence Functions Scale, Brief Pain Inventory, Life Orientation Test-Revised, Center for Epidemiologic Studies Short Depression Scale, and Physical Activity Scale for the Elderly in random counterbalanced order. Structural equation modeling supported chronic pain as positively associated with depressive symptoms and comorbidities and unrelated to physical activity. Depressive symptoms were positively associated with self-negative reminiscence and negatively associated with optimism. Spontaneous reminiscence was not associated with increased physical activity or reduced pain. Individuals may require facilitated integrative reminiscence to assist them in reinterpreting negative memories in a more positive way. Facilitated integrative reminiscence about enjoyed past physical activity is a potential way to increase physical activity, but must be tested in future research. [Res Gerontol Nurs. 2016; 9(5):223-231.]. Copyright 2016, SLACK Incorporated.

  10. Physical activity across adulthood and subjective cognitive function in older men.

    Science.gov (United States)

    Fondell, Elinor; Townsend, Mary Kay; Unger, Leslie Diane; Okereke, Olivia Ifeoma; Grodstein, Francine; Ascherio, Alberto; Willett, Walter Churchill

    2018-01-01

    Low subjective cognitive function (SCF), which is associated with APOE4 genotype, adversely impacts quality of life and has predicted clinical dementia. We examined whether physical activity during early adulthood or mid-to-late life is associated with late-life SCF. We followed 28,481 US male health professionals aged 40-75 years who reported their physical activity in 1986 and biennially thereafter. SCF was reported in 2008 and 2012. The SCF score was averaged for the 2008 and 2012 assessments and categorized as "good", "moderate", and "poor". Men in the highest versus lowest quintile of mid-to-late life physical activity in 1986 had 38% lower odds of poor versus good SCF score (multivariable-adjusted odds ratio (OR) 0.62; 95% CI 0.53, 0.72; P for trend adulthood was also associated with a 23% lower odds of poor SCF, independent of later activity, and being active both in early and mid-to-late adulthood was associated with a 48% lower odds of poor SCF score compared with those who were always sedentary (OR 0.52; 95% CI 0.38, 0.71). Our results suggest that being physically active during early adulthood and mid-to-late life independently contribute to prevention of poor subjective cognitive function in late-life.

  11. The brain of opera singers: experience-dependent changes in functional activation.

    Science.gov (United States)

    Kleber, B; Veit, R; Birbaumer, N; Gruzelier, J; Lotze, M

    2010-05-01

    Several studies have shown that motor-skill training over extended time periods results in reorganization of neural networks and changes in brain morphology. Yet, little is known about training-induced adaptive changes in the vocal system, which is largely subserved by intrinsic reflex mechanisms. We investigated highly accomplished opera singers, conservatory level vocal students, and laymen during overt singing of an Italian aria in a neuroimaging experiment. We provide the first evidence that the training of vocal skills is accompanied by increased functional activation of bilateral primary somatosensory cortex representing articulators and larynx. Opera singers showed additional activation in right primary sensorimotor cortex. Further training-related activation comprised the inferior parietal lobe and bilateral dorsolateral prefrontal cortex. At the subcortical level, expert singers showed increased activation in the basal ganglia, the thalamus, and the cerebellum. A regression analysis of functional activation with accumulated singing practice confirmed that vocal skills training correlates with increased activity of a cortical network for enhanced kinesthetic motor control and sensorimotor guidance together with increased involvement of implicit motor memory areas at the subcortical and cerebellar level. Our findings may have ramifications for both voice rehabilitation and deliberate practice of other implicit motor skills that require interoception.

  12. Study of physiology of visual cortex activated by rotating grating with functional MRI

    International Nuclear Information System (INIS)

    Liang Ping; Shao Qing; Zhang Zhiqiang; Lu Guangming

    2004-01-01

    Objective: To research the physiology of visual cortex activated by rotating grating with functional-MRI (fMRI), and to identify the components of the activation. Methods: Functional MRI was performed in 9 healthy volunteers by using GRE-EPI sequences on a 1.5 T MR scanner. In the block designing, rotating grating, static grating, and luminance were plotted as task states, while static grating, luminance, and darkness were set as control states. The stimuli tasks included six steps. Imaging processing and statistical analysis was carried out off-line using SPM99 in single-subject method. Results: Some respective areas of visual cortex were activated by the various stimuli information supplied by rotating grating. The strong activation in the middle of occipital lobe located at primary vision area was related to the stimuli of white luminance. Its average maximum points were at 13, -98, -2 and 11, -100, -41 The bilateral activations of Brodmann 19th area located at MT area were related to visual motion perception. Its average maximum points were at 46, -72, -2 and -44, -74, 0. The mild activation in the middle of occipital lobe was related to form perception. Its average maximum points were at -12, -98, -6 and -16, -96, -6. Conclusion: The plotting of control state is important in bock design. The effective visual information of rotating grating includes components of luminance, visual motion perception, and form perception. FMRI has potential as a tool for studying the basic physiology of visual cortex. (authors)

  13. The motivational function of an objective in physical activity and sport

    Directory of Open Access Journals (Sweden)

    Mariusz Lipowski

    2017-12-01

    Full Text Available Background As a conscious activity of an individual, physical activity (PA constitutes an element of the free-time dimension. The type of goal allows us to distinguish between sport and PA: sport performance vs. psychophysical health. Drawing on the theory of the motivational function of an objective, this study examined the motivational function of an objective in physical activity and sport. Participants and procedures The sample consisted of 2141 individuals: 1163 women aged 16-64 years (M = 23.90, SD = 8.30 and 978 men aged 16-66 years (M = 24.50, SD = 9.40 who completed the Inventory of Physical Activity Objectives (IPAO, which includes the following scales: 1 motivational value, 2 time management, 3 persistence in action, and 4 motivational conflict. There are also questions that allow one to control for variables such as the variety of forms, duration, and frequency of PA, and socio-demographic variables. Results Males presented different motives of physical activity than females. Motives related to shapely body and health were more important for females. The most important motives for males were physical fitness and shapely body. The gender of participants moderates the motivational value of the specific objectives of physical activity and persistence in action. Conclusions With knowledge about the purposefulness of actions, it is possible to support and shape additional motivation experienced by an individual, by setting new, realistic objectives.

  14. Impact of functional appliances on muscle activity: a surface electromyography study in children.

    Science.gov (United States)

    Woźniak, Krzysztof; Piątkowska, Dagmara; Szyszka-Sommerfeld, Liliana; Buczkowska-Radlińska, Jadwiga

    2015-01-20

    Electromyography (EMG) is the most objective tool for assessing changes in the electrical activity of the masticatory muscles. The purpose of the study was to evaluate the tone of the masseter and anterior temporalis muscles in growing children before and after 6 months of treatment with functional removable orthodontic appliances. The sample conisted of 51 patients with a mean age 10.7 years with Class II malocclusion. EMG recordings were performed by using a DAB-Bluetooth instrument (Zebris Medical GmbH, Germany). Recordings were performed in mandibular rest position, during maximum voluntary contraction (MVC), and during maximum effort. The results of the study indicated that the electrical activity of the muscles in each of the clinical situations was the same in the group of girls and boys. The factor that determined the activity of the muscles was their type. In mandibular rest position and in MVC, the activity of the temporalis muscles was significantly higher that that of the masseter muscels. The maximum effort test indicated a higher fatigue in masseter than in temporalis muscles. Surface electromyography is a useful tool for monitoring muscle activity. A 6-month period of functional therapy resulted in changes in the activity of the masticatory muscles.

  15. Functional localization and effective connectivity of cortical theta and alpha oscillatory activity during an attention task

    Directory of Open Access Journals (Sweden)

    Yuichi Kitaura

    Full Text Available Objectives: The aim of this paper is to investigate cortical electric neuronal activity as an indicator of brain function, in a mental arithmetic task that requires sustained attention, as compared to the resting state condition. The two questions of interest are the cortical localization of different oscillatory activities, and the directional effective flow of oscillatory activity between regions of interest, in the task condition compared to resting state. In particular, theta and alpha activity are of interest here, due to their important role in attention processing. Methods: We adapted mental arithmetic as an attention ask in this study. Eyes closed 61-channel EEG was recorded in 14 participants during resting and in a mental arithmetic task (“serial sevens subtraction”. Functional localization and connectivity analyses were based on cortical signals of electric neuronal activity estimated with sLORETA (standardized low resolution electromagnetic tomography. Functional localization was based on the comparison of the cortical distributions of the generators of oscillatory activity between task and resting conditions. Assessment of effective connectivity was based on the iCoh (isolated effective coherence method, which provides an appropriate frequency decomposition of the directional flow of oscillatory activity between brain regions. Nine regions of interest comprising nodes from the dorsal and ventral attention networks were selected for the connectivity analysis. Results: Cortical spectral density distribution comparing task minus rest showed significant activity increase in medial prefrontal areas and decreased activity in left parietal lobe for the theta band, and decreased activity in parietal-occipital regions for the alpha1 band. At a global level, connections among right hemispheric nodes were predominantly decreased during the task condition, while connections among left hemispheric nodes were predominantly increased. At more

  16. Dynamic Changes in Amygdala Activation and Functional Connectivity in Children and Adolescents with Anxiety Disorders

    Science.gov (United States)

    Swartz, Johnna R.; Phan, K. Luan; Angstadt, Mike; Fitzgerald, Kate D.; Monk, Christopher S.

    2015-01-01

    Anxiety disorders are associated with abnormalities in amygdala function and prefrontal cortex-amygdala connectivity. The majority of fMRI studies have examined mean group differences in amygdala activation or connectivity in children and adolescents with anxiety disorders relative to controls, but emerging evidence suggests that abnormalities in amygdala function are dependent on the timing of the task and may vary across the course of a scanning session. The goal of the present study was to extend our knowledge of the dynamics of amygdala dysfunction by examining whether changes in amygdala activation and connectivity over scanning differ in pediatric anxiety disorder patients relative to typically developing controls during an emotion processing task. Examining changes in activation over time allows for a comparison of how brain function differs during initial exposure to novel stimuli versus more prolonged exposure. Participants included 34 anxiety disorder patients and 19 controls 7 to 19 years old. Participants performed an emotional face matching task during fMRI scanning and the task was divided into thirds in order to examine change in activation over time. Results demonstrated that patients exhibited an abnormal pattern of amygdala activation characterized by an initially heightened amygdala response relative to controls at the beginning of scanning, followed by significant decreases in activation over time. In addition, controls evidenced greater prefrontal cortex-amygdala connectivity during the beginning of scanning relative to patients. These results indicate that differences in emotion processing between the groups vary from initial exposure to novel stimuli relative to more prolonged exposure. Implications are discussed regarding how this pattern of neural activation may relate to altered early-occurring or anticipatory emotion-regulation strategies and maladaptive later-occurring strategies in children and adolescents with anxiety disorders. PMID

  17. Presbycusis Disrupts Spontaneous Activity Revealed by Resting-State Functional MRI

    Directory of Open Access Journals (Sweden)

    Yu-Chen Chen

    2018-03-01

    Full Text Available Purpose: Presbycusis, age-related hearing loss, is believed to involve neural changes in the central nervous system, which is associated with an increased risk of cognitive impairment. The goal of this study was to determine if presbycusis disrupted spontaneous neural activity in specific brain areas involved in auditory processing, attention and cognitive function using resting-state functional magnetic resonance imaging (fMRI approach.Methods: Hearing and resting-state fMRI measurements were obtained from 22 presbycusis patients and 23 age-, sex- and education-matched healthy controls. To identify changes in spontaneous neural activity associated with age-related hearing loss, we compared the amplitude of low-frequency fluctuations (ALFF and regional homogeneity (ReHo of fMRI signals in presbycusis patients vs. controls and then determined if these changes were linked to clinical measures of presbycusis.Results: Compared with healthy controls, presbycusis patients manifested decreased spontaneous activity mainly in the superior temporal gyrus (STG, parahippocampal gyrus (PHG, precuneus and inferior parietal lobule (IPL as well as increased neural activity in the middle frontal gyrus (MFG, cuneus and postcentral gyrus (PoCG. A significant negative correlation was observed between ALFF/ReHo activity in the STG and average hearing thresholds in presbycusis patients. Increased ALFF/ReHo activity in the MFG was positively correlated with impaired Trail-Making Test B (TMT-B scores, indicative of impaired cognitive function involving the frontal lobe.Conclusions: Presbycusis patients have disrupted spontaneous neural activity reflected by ALFF and ReHo measurements in several brain regions; these changes are associated with specific cognitive performance and speech/language processing. These findings mainly emphasize the crucial role of aberrant resting-state ALFF/ReHo patterns in presbycusis patients and will lead to a better understanding of the

  18. Presbycusis Disrupts Spontaneous Activity Revealed by Resting-State Functional MRI.

    Science.gov (United States)

    Chen, Yu-Chen; Chen, Huiyou; Jiang, Liang; Bo, Fan; Xu, Jin-Jing; Mao, Cun-Nan; Salvi, Richard; Yin, Xindao; Lu, Guangming; Gu, Jian-Ping

    2018-01-01

    Purpose : Presbycusis, age-related hearing loss, is believed to involve neural changes in the central nervous system, which is associated with an increased risk of cognitive impairment. The goal of this study was to determine if presbycusis disrupted spontaneous neural activity in specific brain areas involved in auditory processing, attention and cognitive function using resting-state functional magnetic resonance imaging (fMRI) approach. Methods : Hearing and resting-state fMRI measurements were obtained from 22 presbycusis patients and 23 age-, sex- and education-matched healthy controls. To identify changes in spontaneous neural activity associated with age-related hearing loss, we compared the amplitude of low-frequency fluctuations (ALFF) and regional homogeneity (ReHo) of fMRI signals in presbycusis patients vs. controls and then determined if these changes were linked to clinical measures of presbycusis. Results : Compared with healthy controls, presbycusis patients manifested decreased spontaneous activity mainly in the superior temporal gyrus (STG), parahippocampal gyrus (PHG), precuneus and inferior parietal lobule (IPL) as well as increased neural activity in the middle frontal gyrus (MFG), cuneus and postcentral gyrus (PoCG). A significant negative correlation was observed between ALFF/ReHo activity in the STG and average hearing thresholds in presbycusis patients. Increased ALFF/ReHo activity in the MFG was positively correlated with impaired Trail-Making Test B (TMT-B) scores, indicative of impaired cognitive function involving the frontal lobe. Conclusions : Presbycusis patients have disrupted spontaneous neural activity reflected by ALFF and ReHo measurements in several brain regions; these changes are associated with specific cognitive performance and speech/language processing. These findings mainly emphasize the crucial role of aberrant resting-state ALFF/ReHo patterns in presbycusis patients and will lead to a better understanding of the

  19. Beyond Neuronal Activity Markers: Select Immediate Early Genes in Striatal Neuron Subtypes Functionally Mediate Psychostimulant Addiction

    Directory of Open Access Journals (Sweden)

    Ramesh Chandra

    2017-06-01

    Full Text Available Immediate early genes (IEGs were traditionally used as markers of neuronal activity in striatum in response to stimuli including drugs of abuse such as psychostimulants. Early studies using these neuronal activity markers led to important insights in striatal neuron subtype responsiveness to psychostimulants. Such studies have helped identify striatum as a critical brain center for motivational, reinforcement and habitual behaviors in psychostimulant addiction. While the use of IEGs as neuronal activity markers in response to psychostimulants and other stimuli persists today, the functional role and implications of these IEGs has often been neglected. Nonetheless, there is a subset of research that investigates the functional role of IEGs in molecular, cellular and behavioral alterations by psychostimulants through striatal medium spiny neuron (MSN subtypes, the two projection neuron subtypes in striatum. This review article will address and highlight the studies that provide a functional mechanism by which IEGs mediate psychostimulant molecular, cellular and behavioral plasticity through MSN subtypes. Insight into the functional role of IEGs in striatal MSN subtypes could provide improved understanding into addiction and neuropsychiatric diseases affecting striatum, such as affective disorders and compulsive disorders characterized by dysfunctional motivation and habitual behavior.

  20. Association between physical activity in daily life and pulmonary function in adult smokers

    Directory of Open Access Journals (Sweden)

    Miriane Lilian Barboza

    2016-04-01

    Full Text Available Objective: To determine whether the level of physical activity in daily life (PADL is associated with pulmonary function in adult smokers. Methods: We selected 62 adult smokers from among the participants of an epidemiological study conducted in the city of Santos, Brazil. The subjects underwent forced spirometry for pulmonary function assessment. The level of PADL was assessed by the International Physical Activity Questionnaire and triaxial accelerometry, the device being used for seven days. The minimum level of PADL, in terms of quantity and intensity, was defined as 150 min/week of moderate to vigorous physical activity. Correlations between the studied variables were tested with Pearson's or Spearman's correlation coefficient, depending on the distribution of the variables. We used linear multiple regression in order to analyze the influence of PADL on the spirometric variables. The level of significance was set at 5%. Results: Evaluating all predictors, corrected for confounding factors, and using pulmonary function data as outcome variables, we found no significant associations between physical inactivity, as determined by accelerometry, and spirometric indices. The values for FVC were lower among the participants with arterial hypertension, and FEV1/FVC ratios were lower among those with diabetes mellitus. Obese participants and those with dyslipidemia presented with lower values for FVC and FEV1. Conclusions: Our results suggest that there is no consistent association between physical inactivity and pulmonary function in adult smokers. Smoking history should be given special attention in COPD prevention strategies, as should cardiovascular and metabolic comorbidities.

  1. Brain activation to negative stimuli mediates a relationship between adolescent marijuana use and later emotional functioning.

    Science.gov (United States)

    Heitzeg, Mary M; Cope, Lora M; Martz, Meghan E; Hardee, Jillian E; Zucker, Robert A

    2015-12-01

    This work investigated the impact of heavy marijuana use during adolescence on emotional functioning, as well as the brain functional mediators of this effect. Participants (n=40) were recruited from the Michigan Longitudinal Study (MLS). Data on marijuana use were collected prospectively beginning in childhood as part of the MLS. Participants were classified as heavy marijuana users (n=20) or controls with minimal marijuana use. Two facets of emotional functioning-negative emotionality and resiliency (a self-regulatory mechanism)-were assessed as part of the MLS at three time points: mean age 13.4, mean age 19.6, and mean age 23.1. Functional neuroimaging data during an emotion-arousal word task were collected at mean age 20.2. Negative emotionality decreased and resiliency increased across the three time points in controls but not heavy marijuana users. Compared with controls, heavy marijuana users had less activation to negative words in temporal, prefrontal, and occipital cortices, insula, and amygdala. Activation of dorsolateral prefrontal cortex to negative words mediated an association between marijuana group and later negative emotionality. Activation of the cuneus/lingual gyrus mediated an association between marijuana group and later resiliency. Results support growing evidence that heavy marijuana use during adolescence affects later emotional outcomes. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  2. Time-course of Changes in Activation Among Facial Nerve Injury: A Functional Imaging Study.

    Science.gov (United States)

    Xiao, Fu-Long; Gao, Pei-Yi; Sui, Bin-Bin; Wan, Hong; Lin, Yan; Xue, Jing; Zhou, Jian; Qian, Tian-Yi; Wang, Shiwei; Li, Dezhi; Liu, Song

    2015-10-01

    Patients suffering different intervals of facial nerve injury were investigated by functional magnetic resonance imaging to study changes in activation within cortex.Forty-five patients were divided into 3 groups based on intervals of facial nerve injury. Another 16 age and sex-matched healthy participants were included as a control group. Patients and healthy participants underwent task functional magnetic resonance imaging (eye blinking and lip pursing) examination.Functional reorganization after facial nerve injury is dynamic and time-dependent. Correlation between activation in sensorimotor area and intervals of facial nerve injury was significant, with a Pearson correlation coefficient of -0.951 (P nerve injury could be found in late stage of facial dysfunction compared with normal individuals. Dysfunction in the facial nerve has devastating effects on the activity of sensorimotor areas, whereas enhanced intensity in the sensorimotor area ipsilateral to the facial nerve injury in middle stage of facial dysfunction suggests the possible involvement of interhemispheric reorganization. Behavioral or brain stimulation technique treatment in this stage could be applied to alter reorganization within sensorimotor area in the rehabilitation of facial function, monitoring of therapeutic efficacy, and improvement in therapeutic intervention along the course of recovery.

  3. Metabolic Control of Dendritic Cell Activation and Function: Recent Advances and Clinical Implications

    Directory of Open Access Journals (Sweden)

    Bart eEverts

    2014-05-01

    Full Text Available Dendritic cells (DCs are key regulators of both immunity and tolerance by controlling activation and polarization of effector T helper cell and regulatory T cell responses. Therefore, there is a major focus on developing approaches to manipulate DC function for immunotherapy. It is well known that changes in cellular activation are coupled to profound changes in cellular metabolism. Over the past decade there is a growing appreciation that these metabolic changes also underlie the capacity of immune cells to perform particular functions. This has led to the concept that the manipulation of cellular metabolism can be used to shape innate and adaptive immune responses. While most of our understanding in this area has been gained from studies with T cells and macrophages, evidence is emerging that the activation and function of DCs are also dictated by the type of metabolism these cells commit to. We here discuss these new insights and explore whether targeting of metabolic pathways in DCs could hold promise as a novel approach to manipulate the functional properties of DCs for clinical purposes.

  4. TrkB kinase activity maintains synaptic function and structural integrity at adult neuromuscular junctions

    Science.gov (United States)

    Stowe, Jessica M.; Sieck, Dylan C.; Ermilov, Leonid G.; Greising, Sarah M.; Zhang, Chao; Shokat, Kevan M.; Sieck, Gary C.

    2014-01-01

    Activation of the tropomyosin-related kinase receptor B (TrkB) by brain-derived neurotrophic factor acutely regulates synaptic transmission at adult neuromuscular junctions (NMJs). The role of TrkB kinase activity in the maintenance of NMJ function and structure at diaphragm muscle NMJs was explored using a chemical-genetic approach that permits reversible inactivation of TrkB kinase activity in TrkBF616A mice by 1NMPP1. Inhibiting TrkB kinase activity for 7 days resulted in significant, yet reversible, impairments in neuromuscular transmission at diaphragm NMJs. Neuromuscular transmission failure following 2 min of repetitive phrenic nerve stimulation increased from 42% in control to 59% in 1NMPP1-treated TrkBF616A mice (P = 0.010). Recovery of TrkB kinase activity following withdrawal of 1NMPP1 treatment improved neuromuscular transmission (P = 0.006). Electrophysiological measurements at individual diaphragm NMJs documented lack of differences in quantal content in control and 1NMPP1-treated mice (P = 0.845). Morphological changes at diaphragm NMJs were modest following inhibition and recovery of TrkB kinase activity. Three-dimensional reconstructions of diaphragm NMJs revealed no differences in volume at motor end plates (labeled by α-bungarotoxin; P = 0.982) or presynaptic terminals (labeled by synaptophysin; P = 0.515). Inhibition of TrkB kinase activity by 1NMPP1 resulted in more compact NMJs, with increased apposition of presynaptic terminals and motor end plates (P = 0.017) and reduced fragmentation of motor end plates (P = 0.005). Recovery of TrkB kinase activity following withdrawal of 1NMPP1 treatment resulted in postsynaptic remodeling likely reflecting increased gutter depth (P = 0.007), without significant presynaptic changes. These results support an essential role for TrkB kinase activity in maintaining synaptic function and structural integrity at NMJs in the adult mouse diaphragm muscle. PMID:25170066

  5. Activation of the Innate Immune Receptors: Guardians of the Micro Galaxy : Activation and Functions of the Innate Immune Receptors.

    Science.gov (United States)

    De Nardo, Dominic

    2017-01-01

    The families of innate immune receptors are the frontline responders to danger. These superheroes of the host immune systems populate innate immune cells, surveying the extracellular environment and the intracellular endolysosomal compartments and cytosol for exogenous and endogenous danger signals. As a collective the innate immune receptors recognise a wide array of stimuli, and in response they initiate specific signalling pathways leading to activation of transcriptional or proteolytic pathways and the production of inflammatory molecules to destroy foreign pathogens and/or resolve tissue injury. In this review, I will give an overview of the innate immune system and the activation and effector functions of the families of receptors it comprises. Current key concepts will be described throughout, including innate immune memory, formation of innate immune receptor signalosomes, inflammasome formation and pyroptosis, methods of extrinsic cell communication and examples of receptor cooperation. Finally, several open questions and future directions in the field of innate immunity will be presented and discussed.

  6. Functional capacity, physical activity, and quality of life in hypoxemic patients with chronic obstructive pulmonary disease

    Directory of Open Access Journals (Sweden)

    Saglam M

    2015-02-01

    Full Text Available Melda Saglam,1 Naciye Vardar-Yagli,1 Sema Savci,2 Deniz Inal-Ince,1 Ebru Calik Kutukcu,1 Hülya Arikan,1 Lutfi Coplu3 1Department of Physiotherapy and Rehabilitation, Faculty of Health Sciences, Hacettepe University, Ankara, Turkey; 2School of Physiotherapy and Rehabilitation, Dokuz Eylul University, Izmir, Turkey; 3Department of Chest Medicine, Faculty of Medicine, Hacettepe University, Ankara, Turkey Background: The risk of hypoxemia increases with the progression of chronic obstructive pulmonary disease (COPD and the deterioration of pulmonary function. The aim of this study was to compare functional capacity, physical activity, and quality of life in hypoxemic and non-hypoxemic patients with COPD.Methods: Thirty-nine COPD patients (mean age: 62.0±7.03 years were included in this study. Arterial blood gas tensions were measured, and patients were divided into two groups according to oxygen partial pressure (PaO2, the hypoxemic COPD (PaO2 <60 mmHg (n=18, and the control (PaO2 ≥60 mmHg (n=21 groups. Functional exercise capacity was evaluated using the 6-minute walk test (6MWT. Oxygen saturation, dyspnea, and fatigue perception were measured before and after the 6MWT. Physical activity was assessed using the International Physical Activity Questionnaire (IPAQ and an accelerometer. Quality of life was assessed using the St George’s Respiratory Questionnaire (SGRQ.Results: The number of emergency visits and hospitalizations were higher in hypoxemic patients (P<0.05. Lung function parameters, 6MWT distance, exercise oxygen saturation, IPAQ total score, and energy expenditure during daily life were significantly lower, but percentage of maximum heart rate reached during the 6MWT was significantly higher, in hypoxemic COPD patients than in controls (P<0.05.Conclusion: Hypoxemia has a profound effect on functional capacity and physical activity in patients with COPD. Keywords: COPD, hypoxemia, 6-minute walk test

  7. Brain activation in high-functioning older adults and falls: Prospective cohort study.

    Science.gov (United States)

    Verghese, Joe; Wang, Cuiling; Ayers, Emmeline; Izzetoglu, Meltem; Holtzer, Roee

    2017-01-10

    To determine whether brain activity over the prefrontal cortex measured in real time during walking predicts falls in high-functioning older adults. We examined166 older persons (mean age 75 years, 51% women) enrolled in a prospective aging study. High-functioning status defined as the absence of dementia or disability with normal gait diagnosed by study clinicians. The magnitude of task-related changes in oxygenated hemoglobin levels over the prefrontal cortex was measured with functional near-infrared spectroscopy during motor (walking at normal pace) and cognitive (reciting alternate letters of the alphabet) single tasks and a dual-task condition (walking while reciting alternate letters of the alphabet). Incident falls were prospectively assessed over a 50-month study period. Over a mean follow-up of 33.9 ± 11.9 months, 116 falls occurred. Higher levels of prefrontal cortical activation during the dual-task walking condition predicted falls (hazard ratio adjusted for age, sex, education, medical illnesses and general mental status 1.32, 95% confidence interval 1.03-1.70). Neither behavioral outcomes (velocity or letter rate) on the dual task nor brain activation patterns on the single tasks (normal walk or talk alone) predicted falls in this high-functioning sample. The results remained robust after accounting for multiple confounders and for cognitive status, slow gait, previous falls, and frailty. Prefrontal brain activity levels while performing a cognitively demanding walking condition predicted falls in high-functioning seniors. These findings implicate neurobiological processes early in the pathogenesis of falls. © 2016 American Academy of Neurology.

  8. Resistance training for activity limitations in older adults with skeletal muscle function deficits: a systematic review

    Directory of Open Access Journals (Sweden)

    Papa EV

    2017-06-01

    Full Text Available Evan V Papa,1 Xiaoyang Dong,2 Mahdi Hassan1 1Department of Rehabilitation Medicine, The First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi Province, People’s Republic of China; 2Department of Physical Therapy, University of North Texas Health Science Center, Fort Worth, TX, USA Abstract: Human aging results in a variety of changes to skeletal muscle. Sarcopenia is the age-associated loss of muscle mass and is one of the main contributors to musculoskeletal impairments in the elderly. Previous research has demonstrated that resistance training can attenuate skeletal muscle function deficits in older adults, however few articles have focused on the effects of resistance training on functional mobility. The purpose of this systematic review was to 1 present the current state of literature regarding the effects of resistance training on functional mobility outcomes for older adults with skeletal muscle function deficits and 2 provide clinicians with practical guidelines that can be used with seniors during resistance training, or to encourage exercise. We set forth evidence that resistance training can attenuate age-related changes in functional mobility, including improvements in gait speed, static and dynamic balance, and fall risk reduction. Older adults should be encouraged to participate in progressive resistance training activities, and should be admonished to move along a continuum of exercise from immobility, toward the recommended daily amounts of activity. Keywords: aging, strength training, sarcopenia, mobility, balance

  9. CO assisted N2 functionalization activated by a dinuclear hafnium complex: a DFT mechanistic exploration.

    Science.gov (United States)

    Ma, Xuelu; Zhang, Xin; Zhang, Wenchao; Lei, Ming

    2013-01-21

    In this paper, the reaction mechanisms of CO assisted N(2) cleavage and functionalization activated by a dinuclear hafnium complex are studied using a density function theory (DFT) method. Several key intermediates (Ia, Ib, Ic and Id) with axial/equatorial N=C=O coordination structures are found to be of importance along reaction pathways of CO assisted N(2) functionalization, which could provide a profound theoretical insight into the C-N bond formation and N-N bond cleavage. There are two different attack directions to insert the first CO molecule into the Hf-N bonds of the dinuclear hafnium complex, which lead to C-N bond formation. The calculated results imply that CO insertion into the Hf(1)-N(3) bond (Path A1) reacts more easily than that into the Hf(2)-N(3) bond (Path A3). But for the insertion of the second CO insertion to give 2A, there are two possibilities (Path A1 and Path A2) according to this insertion being after/before N-N bond cleavage. Two pathways (Path A1 and Path A2) are proved to be possible to form final dinitrogen functionalized products (oxamidide 2A, 2B and 2C) in this study, which explain the formation of different oxamidide isomers in CO assisted N(2) functionalization activated by a dinuclear hafnium complex.

  10. Physical Activity and Brain Function in Older Adults at Increased Risk for Alzheimer’s Disease

    Directory of Open Access Journals (Sweden)

    Stephen M. Rao

    2013-01-01

    Full Text Available Leisure-time physical activity (PA and exercise training are known to help maintain cognitive function in healthy older adults. However, relatively little is known about the effects of PA on cognitive function or brain function in those at increased risk for Alzheimer’s disease through the presence of the apolipoproteinE epsilon4 (APOE-ε4 allele, diagnosis of mild cognitive impairment (MCI, or the presence of metabolic disease. Here, we examine the question of whether PA and exercise interventions may differentially impact cognitive trajectory, clinical outcomes, and brain structure and function among individuals at the greatest risk for AD. The literature suggests that the protective effects of PA on risk for future dementia appear to be larger in those at increased genetic risk for AD. Exercise training is also effective at helping to promote stable cognitive function in MCI patients, and greater cardiorespiratory fitness is associated with greater brain volume in early-stage AD patients. In APOE-ε4 allele carriers compared to non-carriers, greater levels of PA may be more effective in reducing amyloid burden and are associated with greater activation of semantic memory-related neural circuits. A greater research emphasis should be placed on randomized clinical trials for exercise, with clinical, behavioral, and neuroimaging outcomes in people at increased risk for AD.

  11. Intellectual function, activities of daily living and computerized tomography of the brain in geriatric demented patients

    International Nuclear Information System (INIS)

    Omura, Fumiaki; Ogura, Chikara; Kishimoto, Akira; Okubo, Masayo; Imamoto, Atsushi; Tsuchie, Harutaka; Sugihara, Kanichiro; Fujii, Shozo.

    1984-01-01

    Thirty eight patients of geriatric dementia (mean age 74.9 years) were examined by computerized tomography (CT) and their intellectual functions and activities of daily living (ADL) were evaluated. CT was evaluated by both visual assessment method and direct measuring method. Intellectual function was evaluated by Jikei University dementia rating scale. ADL was evaluated by both Hasegawa's rating scale and Sengoku's rating scale. Results were as follows: significant influence by age was observed in intellectual functions and ADL of subjects above 75 years old. There were good correlations between the higher intellectual function, the better grooming and hygiene, and less needs of nursing care. The severe brain atrophy evaluated by the visual assessment method was correlated with the depressed level of intellectual function. When brain atrophy is mild despite high degree of dementia, reexamination should be made to explore somatic diseases inducing depression of mental activity. It also should be noted that sex and age difference is important in studying geriatric patients. (author)

  12. Healthy elderly people lack neutrophil-mediated functional activity to type V group B Streptococcus.

    Science.gov (United States)

    Amaya, Rene A; Baker, Carol J; Keitel, Wendy A; Edwards, Morven S

    2004-01-01

    To determine the function of capsular polysaccharide (CPS)-specific immunoglobulin-G (IgG) and neutrophils from older adults in increasing ingestion and killing of type V group B Streptococcus (GBS). Cross-sectional study. Outpatient clinic at Baylor College of Medicine. The subjects were 40 healthy, community-dwelling adults aged 65 and older from Houston, Texas. The serum level of type V GBS CPS-specific IgG was measured using an enzyme-linked immunosorbent assay. Functional activity was evaluated using an opsonophagocytosis assay. Sera from four subjects promoted efficient neutrophil-mediated phagocytosis and killing of type V GBS (mean log10 reduction+/-standard deviation in colony-forming units (cfu)=1.51+/-0.39). Each had serum CPS-specific IgG concentrations exceeding 1 microg/mL. Sera from 36 subjects did not promote neutrophil-mediated functional activity (mean log10 reduction in cfu=-0.09+/-0.06; P=.025). Only one of these 36 had a CPS-specific IgG concentration exceeding 1 microg/mL. When pooled sera from young adults given type V GBS conjugate vaccine was added at CPS-specific IgG concentrations of 4 microg/mL or 0.4 microg/mL, sera from all subjects promoted neutrophil-mediated killing of type V GBS. No impairment was evident in the neutrophil function of elderly subjects when it was compared with that of young adults. CPS-specific IgG and neutrophils from healthy older adults function to ingest and kill type V GBS, but these antibodies are not present in sufficient amounts in most individuals. Further studies should determine whether a type V GBS vaccine induces functionally active antibodies in older people.

  13. Amine-functionalized, silver-exchanged zeolite NaY: Preparation, characterization and antibacterial activity

    Energy Technology Data Exchange (ETDEWEB)

    Hanim, Siti Aishah Mohd; Malek, Nik Ahmad Nizam Nik, E-mail: niknizam@fbb.utm.my; Ibrahim, Zaharah

    2016-01-01

    Graphical abstract: - Highlights: • Functionalization of Ag-exchanged zeolite NaY with 3-aminopropyltriethoxysilane APTES (ZSA) as antibacterial agent. • Antibacterial assay of ZSA was performed against Escherichia coli ATCC11229 and Staphylococcus aureus ATCC6538. • Functionalization of Ag-exchanged zeolite NaY with APTES significantly increased the antibacterial agent. • Different mechanisms of bacterial death were suggested for each bacteria type by the functionalized Ag-exchanged zeolite NaY. - Abstract: Amine-functionalized, silver-exchanged zeolite NaY (ZSA) were prepared with three different concentrations of 3-aminopropyltriethoxysilane (APTES) (0.01, 0.20 and 0.40 M) and four different concentrations of silver ions (25%, 50%, 100% and 200% from zeolite cation exchange capacity (CEC)). The samples were characterized by Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), energy-dispersive X-ray (EDX), surface area analysis, thermogravimetric analysis (TGA) and zeta potential (ZP) analysis. The FTIR results indicated that the zeolite was functionalized by APTES and that the intensity of the peaks corresponding to APTES increased as the concentration of APTES used was increased. The antibacterial activities of the silver-exchanged zeolite NaY (ZS) and ZSA were studied against Escherichia coli ATCC11229 and Staphylococcus aureus ATCC6538 using the disc diffusion technique (DDT) and minimum inhibitory concentration (MIC). The antibacterial activity of ZSA increased with the increase in APTES on ZS, and E. coli was more susceptible towards the sample compared to S. aureus. The FESEM micrographs of the bacteria after contact with the ZSA suggested different mechanisms of bacterial death for these two bacteria due to exposure to the studied sample. The functionalization of ZS with APTES improved the antibacterial activity of the silver-zeolite, depending on the concentration of silver

  14. Dissociation of activated protein C functions by elimination of protein S cofactor enhancement.

    LENUS (Irish Health Repository)

    Harmon, Shona

    2008-11-07

    Activated protein C (APC) plays a critical anticoagulant role in vivo by inactivating procoagulant factor Va and factor VIIIa and thus down-regulating thrombin generation. In addition, APC bound to the endothelial cell protein C receptor can initiate protease-activated receptor-1 (PAR-1)-mediated cytoprotective signaling. Protein S constitutes a critical cofactor for the anticoagulant function of APC but is not known to be involved in regulating APC-mediated protective PAR-1 signaling. In this study we utilized a site-directed mutagenesis strategy to characterize a putative protein S binding region within the APC Gla domain. Three single amino acid substitutions within the APC Gla domain (D35T, D36A, and A39V) were found to mildly impair protein S-dependent anticoagulant activity (<2-fold) but retained entirely normal cytoprotective activity. However, a single amino acid substitution (L38D) ablated the ability of protein S to function as a cofactor for this APC variant. Consequently, in assays of protein S-dependent factor Va proteolysis using purified proteins or in the plasma milieu, APC-L38D variant exhibited minimal residual anticoagulant activity compared with wild type APC. Despite the location of Leu-38 in the Gla domain, APC-L38D interacted normally with endothelial cell protein C receptor and retained its ability to trigger PAR-1 mediated cytoprotective signaling in a manner indistinguishable from that of wild type APC. Consequently, elimination of protein S cofactor enhancement of APC anticoagulant function represents a novel and effective strategy by which to separate the anticoagulant and cytoprotective functions of APC for potential therapeutic gain.

  15. LIM domains regulate protein kinase C activity: a novel molecular function.

    Science.gov (United States)

    Maturana, Andrés D; Nakagawa, Noritaka; Yoshimoto, Nobuo; Tatematsu, Kenji; Hoshijima, Masahiko; Tanizawa, Katsuyuki; Kuroda, Shun'ichi

    2011-05-01

    Enigma homolog protein 1 (ENH1) acts as a scaffold that selectively associates protein kinases and transcription factors with cytoskeletal elements. ENH1 comprises an N-terminal PDZ domain and three C-terminal LIM domains. Through the LIM domains ENH1 interacts with the N-terminal region of protein kinase C βI (PKCβI). Here, we show that when ENH1 is co-expressed, PKCβI is translocated from the cytoplasm to the plasma membrane in the absence of any other stimulation. Moreover expression of ENH1 markedly increases PKCβI activity in the absence of PKC activators. A similar activation of PKCβI was observed with co-expression of Cypher1 or Enigma, but not other LIM proteins. The region including the three LIM domains of ENH1 (residues 415-591) appears to be sufficient for this PKCβI activation. Finally, interaction with ENH1 also increases the activity of PKCα and PKCγ, whereas it reduces PKCζ activity. These findings provide strong evidence that ENH1 activates conventional PKCs by directly binding through its LIM domains. Thus, LIM domains have a novel molecular function: the regulation of PKC activities in a PKC isoform-specific manner. Copyright © 2011 Elsevier Inc. All rights reserved.

  16. Structural and functional analyses of DNA-sensing and immune activation by human cGAS.

    Directory of Open Access Journals (Sweden)

    Kazuki Kato

    Full Text Available The detection of cytosolic DNA, derived from pathogens or host cells, by cytosolic receptors is essential for appropriate host immune responses. Cyclic GMP-AMP synthase (cGAS is a newly identified cytosolic DNA receptor that produces cyclic GMP-AMP, which activates stimulator of interferon genes (STING, resulting in TBK1-IRF3 pathway activation followed by the production of type I interferons. Here we report the crystal structure of human cGAS. The structure revealed that a cluster of lysine and arginine residues forms the positively charged DNA binding surface of human cGAS, which is important for the STING-dependent immune activation. A structural comparison with other previously determined cGASs and our functional analyses suggested that a conserved zinc finger motif and a leucine residue on the DNA binding surface are crucial for the DNA-specific immune response of human cGAS, consistent with previous work. These structural features properly orient the DNA binding to cGAS, which is critical for DNA-induced cGAS activation and STING-dependent immune activation. Furthermore, we showed that the cGAS-induced activation of STING also involves the activation of the NF-κB and IRF3 pathways. Our results indicated that cGAS is a DNA sensor that efficiently activates the host immune system by inducing two distinct pathways.

  17. The orexin neuropeptide system: Physical activity and hypothalamic function throughout the aging process.

    Directory of Open Access Journals (Sweden)

    Anastasia N Zink

    2014-11-01

    Full Text Available There is a rising medical need for novel therapeutic targets of physical activity. Physical activity spans from spontaneous, low intensity movements to voluntary, high-intensity exercise. Regulation of spontaneous and voluntary movement is distributed over many brain areas and neural substrates, but the specific cellular and molecular mechanisms responsible for mediating overall activity levels are not well understood. The hypothalamus plays a central role in the control of physical activity, which is executed through coordination of multiple signaling systems, including the orexin neuropeptides. Orexin producing neurons integrate physiological and metabolic information to coordinate multiple behavioral states and modulate physical activity in response to the environment. This review is organized around three questions: (1 How do orexin peptides modulate physical activity? (2 What are the effects of aging and lifestyle choices on physical activity? (3 What are the effects of aging on hypothalamic function and the orexin peptides? Discussion of these questions will provide a summary of the current state of knowledge regarding hypothalamic orexin regulation of physical activity during aging and provide a platform on which to develop improved clinical outcomes in age-associated obesity and metabolic syndromes.

  18. Improving enzymatic activities and thermostability of a tri-functional enzyme with SOD, catalase and cell-permeable activities.

    Science.gov (United States)

    Luangwattananun, Piriya; Eiamphungporn, Warawan; Songtawee, Napat; Bülow, Leif; Isarankura Na Ayudhya, Chartchalerm; Prachayasittikul, Virapong; Yainoy, Sakda

    2017-04-10

    Synergistic action of major antioxidant enzymes, e.g., superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) is known to be more effective than the action of any single enzyme. Recently, we have engineered a tri-functional enzyme, 6His-MnSOD-TAT/CAT-MnSOD (M-TAT/CM), with SOD, CAT and cell-permeable activities. The protein actively internalized into the cells and showed superior protection against oxidative stress-induced cell death over native enzymes fused with TAT. To improve its molecular size, enzymatic activity and stability, in this study, MnSOD portions of the engineered protein were replaced by CuZnSOD, which is the smallest and the most heat resistant SOD isoform. The newly engineered protein, CAT-CuZnSOD/6His-CuZnSOD-TAT (CS/S-TAT), had a 42% reduction in molecular size and an increase in SOD and CAT activities by 22% and 99%, respectively. After incubation at 70°C for 10min, the CS/S-TAT retained residual SOD activity up to 54% while SOD activity of the M-TAT/CM was completely abolished. Moreover, the protein exhibited a 5-fold improvement in half-life at 70°C. Thus, this work provides insights into the design and synthesis of a smaller but much more stable multifunctional antioxidant enzyme with ability to enter mammalian cells for further application as protective/therapeutic agent against oxidative stress-related conditions. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Electronic assessment of disease activity and functioning in patients with axial spondyloarthritis: challenges and unmet needs.

    Science.gov (United States)

    Kiltz, Uta; Boonen, Annelies; Braun, Juergen; Richter, Jutta G

    2016-01-01

    The dynamic clinical course of rheumatic conditions indicates a need for regular collection of information on health status to monitor disease activity and functional status. Patient-reported outcomes measures (PROMs) are playing a key role in the evaluation of symptoms and functioning and health, and are crucial in the initiation of treatment in those patients. In recent years, electronic assessments of PROMs (so called ePROMs) have been introduced. This report summarises some of the rationale, opportunities, and results using ePROMs in patients with spondyloarthritis (SpA).

  20. Enhancing the smoothness of joint motion induced by functional electrical stimulation using co-activation strategies

    Directory of Open Access Journals (Sweden)

    Ruppel Mirjana

    2017-09-01

    Full Text Available The motor precision of today’s neuroprosthetic devices that use artificial generation of limb motion using Functional Electrical Stimulation (FES is generally low. We investigate the adoption of natural co-activation strategies as present in antagonistic muscle pairs aiming to improve motor precision produced by FES. In a test in which artificial knee-joint movements were generated, we could improve the smoothness of FES-induced motion by 513% when applying co-activation during the phases in which torque production is switched between muscles – compared to no co-activation. We further demonstrated how the co-activation level influences the joint stiffness in a pendulum test.

  1. Different patterns of auditory cortex activation revealed by functional magnetic resonance imaging

    International Nuclear Information System (INIS)

    Formisano, E.; Pepino, A.; Bracale, M.; Di Salle, F.; Lanfermann, H.; Zanella, F.E.

    1998-01-01

    In the last few years, functional Magnetic Resonance Imaging (fMRI) has been widely accepted as an effective tool for mapping brain activities in both the sensorimotor and the cognitive field. The present work aims to assess the possibility of using fMRI methods to study the cortical response to different acoustic stimuli. Furthermore, we refer to recent data collected at Frankfurt University on the cortical pattern of auditory hallucinations. Healthy subjects showed broad bilateral activation, mostly located in the transverse gyrus of Heschl. The analysis of the cortical activation induced by different stimuli has pointed out a remarkable difference in the spatial and temporal features of the auditory cortex response to pulsed tones and pure tones. The activated areas during episodes of auditory hallucinations match the location of primary auditory cortex as defined in control measurements with the same patients and in the experiments on healthy subjects. (authors)

  2. Structure-Functional Study of Tyrosine and Methionine Dipeptides: An Approach to Antioxidant Activity Prediction

    Directory of Open Access Journals (Sweden)

    Anna Torkova

    2015-10-01

    Full Text Available Quantum chemical methods allow screening and prediction of peptide antioxidant activity on the basis of known experimental data. It can be used to design the selective proteolysis of protein sources in order to obtain products with antioxidant activity. Molecular geometry and electronic descriptors of redox-active amino acids, as well as tyrosine and methionine-containing dipeptides, were studied by Density Functional Theory method. The calculated data was used to reveal several descriptors responsible for the antioxidant capacities of the model compounds based on their experimentally obtained antioxidant capacities against ABTS (2,2′-Azino-bis-(3-ethyl-benzothiazoline-6-sulfonate and peroxyl radical. A formula to predict antioxidant activity of peptides was proposed.

  3. Physical activity, daily walking, and lower limb lymphedema associate with physical function among uterine cancer survivors.

    Science.gov (United States)

    Brown, Justin C; Lin, Lilie L; Segal, Saya; Chu, Christina S; Haggerty, Ashley E; Ko, Emily M; Schmitz, Kathryn H

    2014-11-01

    We sought to quantify the proportion of uterine cancer survivors who self-report poor physical function. We then sought to quantify the association of poor physical function with physical activity (PA), walking, and lower limb lymphedema (LLL), among women with a history of uterine cancer. Physical function was quantified using the Medical Outcomes Study 12-Item Short-Form Health Survey (SF-12) questionnaire. PA, walking, and LLL were measured using self-report questionnaire. PA was calculated using metabolic equivalent hours per week (MET-h week(-1)), and walking was calculated using blocks per day (blocks day(-1)). Logistic regression estimated odds ratios (OR) and 95 % confidence intervals (95 % CI). Among the 213 uterine cancer survivors in our survey (43 % response rate), 35 % self-reported poor physical function. Compared to participants who reported <3.0 MET-h week(-1) of PA, participants who reported ≥18.0 MET-h week(-1) of PA were less likely to have poor physical function (OR 0.03, 95 % CI 0.01-0.10; P trend  < 0.0001). Compared to participants who reported <4.0 blocks day(-1) of walking, participants who reported ≥12.0 blocks day(-1) of walking were less likely to have poor physical function (OR 0.07, 95 % CI 0.03-0.19; P trend  < 0.0001). Compared to participants who did not have LLL, participants with LLL were more likely to have poor physical function (OR 5.25, 95 % CI 2.41-11.41; P < 0.0001). Higher levels of PA and walking associate with a lower likelihood of reporting poor physical function. The presence of LLL associates with a higher likelihood of reporting poor physical function. These findings are hypothesis-generating and should be evaluated in future prospective studies.

  4. Aryl Hydrocarbon Receptor Activation Reduces Dendritic Cell Function during Influenza Virus Infection

    Science.gov (United States)

    Jin, Guang-Bi; Moore, Amanda J.; Head, Jennifer L.; Neumiller, Joshua J.; Lawrence, B. Paige

    2010-01-01

    It has long been known that activation of the aryl hydrocarbon receptor (AhR) by ligands such as 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) suppresses T cell–dependent immune responses; however, the underlying cellular targets and mechanism remain unclear. We have previously shown that AhR activation by TCDD reduces the proliferation and differentiation of influenza virus–specific CD8+ T cells through an indirect mechanism; suggesting that accessory cells are critical AhR targets during infection. Respiratory dendritic cells (DCs) capture antigen, migrate to lymph nodes, and play a key role in activating naive CD8+ T cells during respiratory virus infection. Herein, we report an examination of how AhR activation alters DCs in the lung and affects their trafficking to and function in the mediastinal lymph nodes (MLN) during infection with influenza virus. We show that AhR activation impairs lung DC migration and reduces the ability of DCs isolated from the MLN to activate naive CD8+ T cells. Using novel AhR mutant mice, in which the AhR protein lacks its DNA-binding domain, we show that the suppressive effects of TCDD require that the activated AhR complex binds to DNA. These new findings suggest that AhR activation by chemicals from our environment impacts DC function to stimulate naive CD8+ T cells and that immunoregulatory genes within DCs are critical targets of AhR. Moreover, our results reinforce the idea that environmental signals and AhR ligands may contribute to differential susceptibilities and responses to respiratory infection. PMID:20498003

  5. Visual feedback alters force control and functional activity in the visuomotor network after stroke

    Directory of Open Access Journals (Sweden)

    Derek B. Archer

    2018-01-01

    Full Text Available Modulating visual feedback may be a viable option to improve motor function after stroke, but the neurophysiological basis for this improvement is not clear. Visual gain can be manipulated by increasing or decreasing the spatial amplitude of an error signal. Here, we combined a unilateral visually guided grip force task with functional MRI to understand how changes in the gain of visual feedback alter brain activity in the chronic phase after stroke. Analyses focused on brain activation when force was produced by the most impaired hand of the stroke group as compared to the non-dominant hand of the control group. Our experiment produced three novel results. First, gain-related improvements in force control were associated with an increase in activity in many regions within the visuomotor network in both the stroke and control groups. These regions include the extrastriate visual cortex, inferior parietal lobule, ventral premotor cortex, cerebellum, and supplementary motor area. Second, the stroke group showed gain-related increases in activity in additional regions of lobules VI and VIIb of the ipsilateral cerebellum. Third, relative to the control group, the stroke group showed increased activity in the ipsilateral primary motor cortex, and activity in this region did not vary as a function of visual feedback gain. The visuomotor network, cerebellum, and ipsilateral primary motor cortex have each been targeted in rehabilitation interventions after stroke. Our observations provide new insight into the role these regions play in processing visual gain during a precisely controlled visuomotor task in the chronic phase after stroke.

  6. A conserved cysteine motif is critical for rice ceramide kinase activity and function.

    Directory of Open Access Journals (Sweden)

    Fang-Cheng Bi

    Full Text Available Ceramide kinase (CERK is a key regulator of cell survival in dicotyledonous plants and animals. Much less is known about the roles of CERK and ceramides in mediating cellular processes in monocot plants. Here, we report the characterization of a ceramide kinase, OsCERK, from rice (Oryza sativa spp. Japonica cv. Nipponbare and investigate the effects of ceramides on rice cell viability.OsCERK can complement the Arabidopsis CERK mutant acd5. Recombinant OsCERK has ceramide kinase activity with Michaelis-Menten kinetics and optimal activity at 7.0 pH and 40°C. Mg2+ activates OsCERK in a concentration-dependent manner. Importantly, a CXXXCXXC motif, conserved in all ceramide kinases and important for the activity of the human enzyme, is critical for OsCERK enzyme activity and in planta function. In a rice protoplast system, inhibition of CERK leads to cell death and the ratio of added ceramide and ceramide-1-phosphate, CERK's substrate and product, respectively, influences cell survival. Ceramide-induced rice cell death has apoptotic features and is an active process that requires both de novo protein synthesis and phosphorylation, respectively. Finally, mitochondria membrane potential loss previously associated with ceramide-induced cell death in Arabidopsis was also found in rice, but it occurred with different timing.OsCERK is a bona fide ceramide kinase with a functionally and evolutionarily conserved Cys-rich motif that plays an important role in modulating cell fate in plants. The vital function of the conserved motif in both human and rice CERKs suggests that the biochemical mechanism of CERKs is similar in animals and plants. Furthermore, ceramides induce cell death with similar features in monocot and dicot plants.

  7. An AP endonuclease functions in active DNA demethylation and gene imprinting in Arabidopsis [corrected].

    Directory of Open Access Journals (Sweden)

    Yan Li

    2015-01-01

    Full Text Available Active DNA demethylation in plants occurs through base excision repair, beginning with removal of methylated cytosine by the ROS1/DME subfamily of 5-methylcytosine DNA glycosylases. Active DNA demethylation in animals requires the DNA glycosylase TDG or MBD4, which functions after oxidation or deamination of 5-methylcytosine, respectively. However, little is known about the steps following DNA glycosylase action in the active DNA demethylation pathways in plants and animals. We show here that the Arabidopsis APE1L protein has apurinic/apyrimidinic endonuclease activities and functions downstream of ROS1 and DME. APE1L and ROS1 interact in vitro and co-localize in vivo. Whole genome bisulfite sequencing of ape1l mutant plants revealed widespread alterations in DNA methylation. We show that the ape1l/zdp double mutant displays embryonic lethality. Notably, the ape1l+/-zdp-/- mutant shows a maternal-effect lethality phenotype. APE1L and the DNA phosphatase ZDP are required for FWA and MEA gene imprinting in the endosperm and are important for seed development. Thus, APE1L is a new component of the active DNA demethylation pathway and, together with ZDP, regulates gene imprinting in Arabidopsis.

  8. Motor association cortex activity in Parkinson's disease. A functional MRI study

    International Nuclear Information System (INIS)

    Tada, Yukiko

    1998-01-01

    The purpose of this study was to examine the activation of motor association cortex using functional magnetic resonance imaging (fMRI) in patients with Parkinson's disease (PD) and control subjects during performed hand movements. There were 26 patients with PD (12 patients with Hoehn and Yahr stage I-II, 14 patients with stage III) and 8 control subjects. Functional imaging was performed using a 1.5 tesla MRI system equipped with a single-shot, echo-planar pulse sequence. The significant signal changes were observed within the primary sensorimotor area, the supplementary motor area (SMA), and the parietal association area in both PD and control subjects. In PD subjects, the SMA was less activated than in control subjects; there were significant differences in the number of pixels activated in SMA between control and Yahr III group (p<0.01), and between Yahr I-II and Yahr III group (p<0.01). Our results demonstrated that movement related cerebral activity in the SMA is reduced in PD subjects, consistent with previously published data using other methods. It is well known from anatomical studies that one of the major cortical outputs of the basal ganglia is the SMA. This may explain the hypoactivation of the SMA in PD. Studies using fMRI provide a promising method not only for localizing cortical activation related to voluntary movements but also for investigating pathophysiology of movement disorders. (author)

  9. Semisynthetic modifications of hemiaminal function at ornithine unit of mulundocandin, towards chemical stability and antifungal activity.

    Science.gov (United States)

    Lal, Bansi; Gund, Vitthal Genbhau; Gangopadhyay, Ashok Kumar; Nadkarni, S R; Dikshit, Vidula; Chatterjee, D K; Shirvaikar, R

    2003-11-17

    Mulundocandin (1), is an echinocandin class of lipopeptide. It has wide spectrum of antifungal activity against Candida and Aspergillus species. Semisynthetic modification at Ornithine-5-hydroxyl (hemiaminal function) of 1 was carried out to improve solution stability and hence in vivo activity. Synthesis of ether (C-OR), thioether (C-SR) and C-N linkage at hemiaminal function have been described. All synthetic analogues were evaluated for their stability in aqueous solution and found to be more stable than mulundocandin. Antifungal activity of Orn-5 analogues was evaluated both in vitro against Candida albicans and Aspergillus fumigatus by agar well method and in vivo (oral and intraperitoneal) in C. albicans infected Swiss mice. Results of in vivo assays of analogues 2-9 by the oral route suggests that the introduction of either oxygen nucleophiles (-OR) or sulphur nucleophiles (-SR), at either Orn-5 or at both Orn-5 and HTyr-4 positions, results in retaining the activity of the parent compound with improved aqueous stability in most cases. Compound 9 has shown improved antifungal activity in comparison to mulundocandin by oral application in Swiss mice.

  10. Conserved TRAM Domain Functions as an Archaeal Cold Shock Protein via RNA Chaperone Activity

    Directory of Open Access Journals (Sweden)

    Bo Zhang

    2017-08-01

    Full Text Available Cold shock proteins (Csps enable organisms to acclimate to and survive in cold environments and the bacterial CspA family exerts the cold protection via its RNA chaperone activity. However, most Archaea do not contain orthologs to the bacterial csp. TRAM, a conserved domain among RNA modification proteins ubiquitously distributed in organisms, occurs as an individual protein in most archaeal phyla and has a structural similarity to Csp proteins, yet its biological functions remain unknown. Through physiological and biochemical studies on four TRAM proteins from a cold adaptive archaeon Methanolobus psychrophilus R15, this work demonstrated that TRAM is an archaeal Csp and exhibits RNA chaperone activity. Three TRAM encoding genes (Mpsy_0643, Mpsy_3043, and Mpsy_3066 exhibited remarkable cold-shock induced transcription and were preferentially translated at lower temperature (18°C, while the fourth (Mpsy_2002 was constitutively expressed. They were all able to complement the cspABGE mutant of Escherichia coli BX04 that does not grow in cold temperatures and showed transcriptional antitermination. TRAM3066 (gene product of Mpsy_3066 and TRAM2002 (gene product of Mpsy_2002 displayed sequence-non-specific RNA but not DNA binding activity, and TRAM3066 assisted RNases in degradation of structured RNA, thus validating the RNA chaperone activity of TRAMs. Given the chaperone activity, TRAM is predicted to function beyond a Csp.

  11. A comparison of the function, activity and participation and quality of life between down syndrome children and typically developing children.

    Science.gov (United States)

    Jung, Hee-Kyoung; Chung, EunJung; Lee, Byoung-Hee

    2017-08-01

    [Purpose] To compare function, activity, participation, and quality of life of Down syndrome children and typically developing children according to age. [Subjects and Methods] A total of 16 Down syndrome children and 20 children with typical development were included as subjects for this study. International Classification of Functioning, Disability, and Health (ICF) Child and Youth version (CY) developed by the World Health Organization (WHO) and a questionnaire were used to measure children's functioning, activity, and participation. To measure quality of life, KIDSCREEN 52-HRQOL questionnaire was used in this study. [Results] ICF-CY function, activity, participation, and quality of life showed statistically significant differences between Down syndrome children and typically developing children. Down syndrome children with higher functions showed higher activities and participation. Higher function, activity and participation features were correlated with better quality of life. Higher function resulted in better quality of life. [Conclusion] Function, activity, participation, quality of life, and several common factors of Down syndrome children depend on the ability of children. Function of Down syndrome children affects their activity, participation, and quality of life. Activities and participations also affect quality of life. Therefore, children's functional aspect is the foundation for quality of life.

  12. Immune function and phenotype before and after highly active antiretroviral therapy

    DEFF Research Database (Denmark)

    Søndergaard, S R; Aladdin, H; Ullum, H

    1999-01-01

    Immune functions represented by equal CD4 counts before and after highly active antiretroviral therapy (i.e., pre- and post-HAART) in the same HIV-infected patients, were examined. Twelve HIV-infected patients were included. Patients had equal CD4 counts pre- and post-HAART and were studied...... expression of CD38 on T cells, indicates that following long-term HAART, repopulation occurs with less activated cells with increased proliferative capacity. This finding may be of clinical importance in considering risk and vulnerability for progression of opportunistic infections post-HAART....

  13. Features functional activity kinesthetic and visual sensory systems in athletes of different specializations

    Directory of Open Access Journals (Sweden)

    Anatoliy Rovnyy

    2015-02-01

    Full Text Available Purpose: to establish specific effects of different sports on functional status and co mood kinesthetic and visual analyzers skilled athletes. Materials and Methods: the study was conducted on athletes qualified five sports: modern pentathlon, volleyball, basketball, handball and fencing. We used methods of difference sensometry and mathematical statistics. Results revealed that the sensitivity of sensor systems depend on the specifics of sports activities and sports equipment. Conclusions: the complex is set internally sensor and between sensory bonds that are formed on the basis of the specific sports activity.

  14. Robust stability analysis of delayed Takagi-Sugeno fuzzy Hopfield neural networks with discontinuous activation functions.

    Science.gov (United States)

    Wu, Xiru; Wang, Yaonan; Huang, Lihong; Zuo, Yi

    2010-12-01

    In this paper, the global robust stability problem of delayed Takagi-Sugeno fuzzy Hopfield neural networks with discontinuous activation functions (TSFHNNs) is considered. Based on Lyapunov stability theory and M-matrices theory, we derive a stability criterion to guarantee the global robust stability of TSFHNNs. Compared with the existing literature, we remove the assumptions on the neuron activations such as Lipschitz conditions, bounded, monotonic increasing property or the assumption that the right-limit value is bigger than the left one at the discontinuous point. Finally, two numerical examples are given to show the effectiveness of the proposed stability results.

  15. How much in vitro cholesterol reducing activity of lactobacilli predicts their in vivo cholesterol function?

    Directory of Open Access Journals (Sweden)

    Golnoush Madani

    2013-01-01

    Results: No cholesterol assimilation was detected by growth and incubation of the active culture in either of the medium. Thus, in vivo cholesterol function of LA7 was not caused by cholesterol consumption. A comprehensive review of literature on the related studies also showed that there are other documented studies which evidenced the uncertainty of the direct relation between in vitro and in vivo studies. Conclusion: Cholesterol removal from the cultured media may not be considered as an appropriate integral index for selection of Lactobacillus strains with cholesterol-lowering activity.

  16. Taurine Supplementation Improves Functional Capacity, Myocardial Oxygen Consumption, and Electrical Activity in Heart Failure.

    Science.gov (United States)

    Ahmadian, Mehdi; Dabidi Roshan, Valiollah; Ashourpore, Eadeh

    2017-07-04

    Taurine is an amino acid found abundantly in the heart in very high concentrations. It is assumed that taurine contributes to several physiological functions of mammalian cells, such as osmoregulation, anti-inflammation, membrane stabilization, ion transport modulation, and regulation of oxidative stress and mitochondrial protein synthesis. The objective of the current study was to evaluate the effectiveness of taurine supplementation on functional capacity, myocardial oxygen consumption, and electrical activity in patients with heart failure. In a double-blind and randomly designed study, 16 patients with heart failure were assigned to two groups: taurine (TG, n = 8) and placebo (PG, n = 8). TG received 500-mg taurine supplementation three times per day for two weeks. Significant decrease in the values of Q-T segments (p taurine concentration, T wave, Q-T segment, physical capacities, and lower values of cardiovascular capacities were detected post-supplementation in TG as compared with PG (all p values Taurine significantly enhanced the physical function and significantly reduced the cardiovascular function parameters following exercise. Our results also suggest that the short-term taurine supplementation is an effective strategy for improving some selected hemodynamic parameters in heart failure patients. Together, these findings support the view that taurine improves cardiac function and functional capacity in patients with heart failure. This idea warrants further study.

  17. Effects of soil type and farm management on soil ecological functional genes and microbial activities

    Energy Technology Data Exchange (ETDEWEB)

    Reeve, Jennifer [Washington State University; Schadt, Christopher Warren [ORNL; Carpenter-Boggs, Lynne [Washington State University; Kang, S. [University of Oklahoma; Zhou, Jizhong [University of Oklahoma, Norman; Reganold, John P. [Washington State University

    2010-01-01

    Relationships between soil microbial diversity and soil function are the subject of much debate. Process-level analyses have shown that microbial function varies with soil type and responds to soil management. However, such measurements cannot determine the role of community structure and diversity in soil function. The goal of this study was to investigate the role of gene frequency and diversity, measured by microarray analysis, on soil processes. The study was conducted in an agro-ecosystem characterized by contrasting management practices and soil types. Eight pairs of adjacent commercial organic and conventional strawberry fields were matched for soil type, strawberry variety, and all other environmental conditions. Soil physical, chemical and biological analyses were conducted including functional gene microarrays (FGA). Soil physical and chemical characteristics were primarily determined by soil textural type (coarse vs fine-textured), but biological and FGA measures were more influenced by management (organic vs conventional). Organically managed soils consistently showed greater functional activity as well as FGA signal intensity (SI) and diversity. Overall FGA SI and diversity were correlated to total soil microbial biomass. Functional gene group SI and/or diversity were correlated to related soil chemical and biological measures such as microbial biomass, cellulose, dehydrogenase, ammonium and sulfur. Management was the dominant determinant of soil biology as measured by microbial gene frequency and diversity, which paralleled measured microbial processes.

  18. Structural Waters Define a Functional Channel Mediating Activation of the GPCR, rhodopsin

    Energy Technology Data Exchange (ETDEWEB)

    Angel, T.; Gupta, S; Jastrzebska, B; Palczewski, K; Chance, M