WorldWideScience

Sample records for azobenzene side groups

  1. Photophysical characteristics of polyaniline with photochromic azobenzene side groups

    Institute of Scientific and Technical Information of China (English)

    Feng Wei; Huang Kun; Wan Mei-Xiang

    2005-01-01

    Photochromic characteristics and optical molecular reorientation in conducting polymer such as polyaniline derivatives containing photochromic azobenzene moieties (PAPNPAPOA) in side chain are studied. Changes in the UV-vis absorption, refractive index, thickness, contact angle and morphology of these films after irradiation of a linearly polarized light with a wavelength of 365nm are measured. The trans-cis isomerization of PAPNPAPOA is proved irreversible even after withdrawing the UV light for a long time. That the structure of main-chain attends by the trans-cis isomerization of side-chain is confirmed by the absorption and the solution colour during the UV irradiation. These effects are discussed by taking the trans-cis isomerization of azobenzene into consideration.

  2. Photoorientation of a liquid crystalline polyester with azobenzene side groups

    DEFF Research Database (Denmark)

    Zebger, I; Rutloh, M; Hoffmann, U;

    2002-01-01

    -g) is achieved by a low power density (1 mW/cm(2) and dose of 0.5 mW/cm(2)s). Higher power densities result in a decrease of the maximum dichroism and, finally, the initially induced small anisotropy is erased during continuing light exposure. At a constant high power density of about 700 mW/cm(2......The photoorientation process in a polyester with 4-cyano-4'-alkoxyazobenzene side group and long methylene spacers in the side and the main-chain was studied as a function of irradiation with linearly polarized light of 488 nm under systematic variation of the power density and temperature...

  3. Photoorientation of a liquid-crystalline polyester with azobenzene side groups: Effects of irradiation with linearly polarized red light after photochemical pretreatment

    DEFF Research Database (Denmark)

    Zebger, Ingo; Rutloh, Michael; Hoffmann, Uwe;

    2003-01-01

    In contrast to the conventional photoorientation process with blue light, an orientation of 4-cyano-4'-alkoxyazobenzene side groups parallel to the electric field vector of the incident light is generated upon irradiating films of a liquid-crystalline side-chain polymer with linearly polarized red...... of this two-step process is the angular-selective transformation of the bulky Z-isomers to the rodlike E-isomeric formed by the red light. The aligned E-azobenzene side groups become strongly J-aggregated. Very high values of dichroism of about 0.8 and birefringence of about 0.3 were generated as a result...... light. The polyester is characterized by smectic and nematic phases g24SX26SA34N46i and a strong tendency to form J-aggregates. The process requires a photochemical pretreatment by irradiation with UV light or an exposure to visible light of high power density to produce a certain concentration of the Z...

  4. Light scattering of thin azobenzene side-chain polyester layers

    DEFF Research Database (Denmark)

    Kerekes, Á.; Lörincz, E.; Ramanujam, P.S.;

    2002-01-01

    Light scattering properties of liquid crystalline and amorphous azobenzene side-chain polyester layers used for optical data storage were examined by means of transmissive scatterometry. Comparative experiments show that the amorphous polyester has significantly lower light scattering characteris...... for the domain size in thin liquid crystalline polyester layers being responsible for the dominant light scattering. The characteristic domain Sizes obtained from the Fourier transformation of polarization microscopic Pictures confirm these values.......Light scattering properties of liquid crystalline and amorphous azobenzene side-chain polyester layers used for optical data storage were examined by means of transmissive scatterometry. Comparative experiments show that the amorphous polyester has significantly lower light scattering...

  5. Photoinduced Circular Anisotropy in Side-Chain Azobenzene Polyesters

    DEFF Research Database (Denmark)

    Nikolova, L.; Todorov, T.; Ivanov, M.;

    1997-01-01

    We report for the first time the inducing of large circular anisotropy in previously unoriented films of side-chain azobenzene polyesters on illumination with circularly polarized light at a wavelength of 488 nm. The circular dichroism and optical activity are measured simultaneously in real time...

  6. Holographic Gratings in Azobenzene Side-Chain Polymethacrylates

    DEFF Research Database (Denmark)

    Andruzzi, Luisa; Altomare, Angelina; Ciardelli, Francesco;

    1999-01-01

    Optical storage properties of thin unoriented liquid crystalline and amorphous side-chain azobenzene polymethacrylate films are examined by polarization holographic measurements. The investigated materials are free radical copolymers derived from two photochromic monomers, 6-(4-oxy-4'-cyanoazoben......Optical storage properties of thin unoriented liquid crystalline and amorphous side-chain azobenzene polymethacrylate films are examined by polarization holographic measurements. The investigated materials are free radical copolymers derived from two photochromic monomers, 6-(4-oxy-4...... polarizing optical microscopy. Atomic force microscopy investigations have been carried out on the polarization holographic gratings recorded in the polymethacrylate films. A surface relief grating has been found to appear in all films after irradiation. The copolymers with 50-75% dye content exhibit the...

  7. Surface relief measurements in side-chain azobenzene polyesters with different substituents

    DEFF Research Database (Denmark)

    Helgert, M.; Wenke, L.; Hvilsted, Søren;

    2001-01-01

    Light-induced surface modification of a series of liquid-crystalline side-chain azobenzene polyesters which have the same main- and side-chain structure but eleven different substituents on the azobenzene is investigated. Using a transmission mask as well as single focused beams we show that the...... azobenzene polyester was included in the study for comparison. The results point to a mechanism of the surface relief phenomenon, in which the architecture of the polyesters plays a crucial role....

  8. Determination of the Response Time of Photoanisotropy in Azobenzene Side-Chain Polyesters

    DEFF Research Database (Denmark)

    Bublitz, D.; Fleck, B.; Wenke, L.;

    2000-01-01

    We present a method which allows the determination of the response time to polarized light of an azobenzene side-chain polyester. This method is based on the measurement of intensities in dependence on the delay time between a pump and a probe pulse. The described method does not need a very...

  9. Diffraction from polarization holographic gratings with surface relief in side-chain azobenzene polyesters

    DEFF Research Database (Denmark)

    Naydenova, I; Nikolova, L; Todorov, T;

    1998-01-01

    We investigate the polarization properties of holographic gratings in side-chain azobenzene polyesters in which an anisotropic grating that is due to photoinduced linear and circular birefringence is recorded in the volume of the material and a relief grating appears on the surface. A theoretical...

  10. Theoretical model of photoinduced anisotropy in liquid-crystalline azobenzene side-chain polyesters

    DEFF Research Database (Denmark)

    Pedersen, Thomas Garm; Johansen, Per Michael; Holme, N.C.R.;

    1998-01-01

    A theoretical framework for the temporal behavior of photoinduced anisotropy in liquid-crystalline azobenzene side-chain polyesters is constructed. The domain structure of the material is taken into account and inter molecular interactions are included through a mean-field description. Photoinduced...

  11. Photoinduced anisotropy measurements in liquid-crystalline azobenzene side-chain polyesters

    DEFF Research Database (Denmark)

    Holme, NCR; Ramanujam, P.S.; Hvilsted, Søren

    1996-01-01

    Reversible photoinduced anisotropy in a series of Liquid-crystalline azobenzene side-chain polyesters is investigated as a function of intensity of the write beam and the sample temperature. Measurements reveal that the erasing takes place at a temperature much higher than the glass transition...... temperature. induced anisotropy can be erased by heating the polyesters to approximately 80 degrees C....

  12. Inverse Relaxation of Photoinduced Birefringence in a Liquid-Crystalline Azobenzene Side-Chain Polymer

    Institute of Scientific and Technical Information of China (English)

    PAN Xu; WANG Chang-Shun; ZHANG Xiao-Qiang

    2008-01-01

    Photoinduced birefringence in a liquid-crystalline azobenzene side-chain polymer is investigated. It is observed that the birefringence does not show any decay but increases after switching off the pump light at room temperature. The magnitude of the birefringence relaxation is found to depend on the exposure dose of the pump light.A discussion about the mechanism of the inverse relaxation of birefringence is presented.

  13. Microscopic theory of light-induced deformation in amorphous side-chain azobenzene polymers.

    Science.gov (United States)

    Toshchevikov, V; Saphiannikova, M; Heinrich, G

    2009-04-16

    We propose a microscopic theory of light-induced deformation of side-chain azobenzene polymers taking into account the internal structure of polymer chains. Our theory is based on the fact that interaction of chromophores with the polarized light leads to the orientation anisotropy of azobenzene macromolecules which is accompanied by the appearance of mechanical stress. It is the first microscopic theory which provides the value of the light-induced stress larger than the yield stress. This result explains a possibility for the inscription of surface relief gratings in glassy side-chain azobenzene polymers. For some chemical architectures, elongation of a sample demonstrates a nonmonotonic behavior with the light intensity and can change its sign (a stretched sample starts to be uniaxially compressed), in agreement with experiments. Using a viscoplastic approach, we show that the irreversible strain of a sample, which remains after the light is switched off, decreases with increasing temperature and can disappear at certain temperature below the glass transition temperature. This theoretical prediction is also confirmed by recent experiments.

  14. OPTICAL PHASE CONJUGATION RESPONSE OF PHOTOINDUCED POLYMER FILMS CONTAINING AZOBENZENE MOIETIES WITH CHIRAL GROUP

    Institute of Scientific and Technical Information of China (English)

    Ze-da Xu; Yong Zhang; Xing-he Fan; Xin-hua Wan; Qi-feng Zhou

    2002-01-01

    An optically active monomer containing azobenzene moieties with chiral group (s-2-methyl-butyl), 4-[2-(methacryloyloxy)ethyloxy]-4'-(s-2-methyl-1-butyloxycarbonyl) azobenzene (M1) was synthesized. Polymer (PM1) possessing optical phase conjugated response was obtained by homopolymerization of the optically active monomer (M1) using free radical polymerization. The polymer was very soluble in common solvents and good optical quality films could be easily fabricated by spin coating. The optical phase conjugated responses of the polymer PM1 were measured by degenerate four-wave mixing (DFWM). In comparison with polymer containing no chiral group, it was found from the preliminary measurement of photoisomeric change that optical phase conjugated response of the PM1 in the long-range order hexagonal symmetry microstructure could be easily controlled by choosing the appropriate polarization direction of the irradiating beams (514.5 nm) and the irradiating number, presumably due to the chiral group in the PM1 molecular structure. For the case of the polymer investigated here, a chiral group side chain was introduced to increase optical phase conjugated response intensity with different polarization directions of the irradiating beams, which aims originally at searching for a new photoactive material.

  15. Azobenzene side-chain liquid crystalline polyesters with outstanding optical storage properties

    DEFF Research Database (Denmark)

    Hvilsted, Søren; Pedersen, M; Holme, NCR;

    1998-01-01

    ,000 are routinely obtained by melt transesterification of the novel diols and selected diacid precursors (parameter iii). Prominent storage features include no prealignment of thin SCLC polyester films prior to the writing process, and sensitivity in a broad laser wavelength window (415-532 nm). Additionally......, the observed surface roughness is strongly dependent on the laser polarization. Polarization Fourier-Transform infrared studies of laser induced segmental motion in selectively deuterated SCLC cyanoazobenzene polyesters have revealed that not only the azobenzene chromophores but also main-chain and side......-chain spacers align preferentially perpendicular to laser polarization....

  16. SYNTHESIS AND CHARACTERIZATION OF POLYMERS BEARING AZOBENZENE AND CARBAZOLE GROUPS VIA POST-AZO-COUPLING REACTION

    Institute of Scientific and Technical Information of China (English)

    Jun Shi; Zhi-wei Jiang; Li Zhang; Shao-kui Cao

    2005-01-01

    A series of polymers bearing azobenzene and carbazole groups for photorefractive purpose were prepared via post-azo-coupling reaction. The successful reaction was identified by spectroscopic analysis and gel permeation chromatography. This approach is more facile compared with the direct polymerization of corresponding functional monomer. The polymers prepared have weight average molecular weight of higher than 1.5 × 104 and are easily soluble in common organic solvents like chloroform and tetrahydrofuran, polymer films with high optical quality could be easily fabricated through solution casting. Glass transition temperature (Tg) of the polymers ranges from 60℃ to 182℃, depending on the alkylene spacer length between the functional side group and the polymer backbone, and the polymers are relatively stable under 300℃.

  17. Triphenyl group containing molecular glasses of azobenzene for photonic applications

    Science.gov (United States)

    Zarins, Elmars; Tokmakovs, Andrejs; Kokars, Valdis; Ozols, Andris; Augustovs, Peteris; Rutkis, Martins

    2016-03-01

    D-π-A type organic molecules have attracted considerable attention of scientists due to their potential applications in nonlinear optics and holographic data storage as light, flexible and low-cost photonic materials. To provide a better understanding on the relation between the compound chemical structure and their physical properties necessary for the mentioned purposes, eight glassy triphenyl group containing derivatives of azobenzene with incorporated 5,5-dimethylcyclohex-2-enylidene or 4H-pyran-4-ylidene structural fragments and dicyanomethylene, indene-1,3-dione and pyrimidine-2,4,6(1H,3H,5H)-trione acceptor groups have been synthesized and investigated. Thermal stability of synthesized glasses is no lower than 250 °C and glass transition in higher than 70 °C which both further increases (up to 120 °C) by additional number of attached triphenyl-moieties and incorporated structural fragments. Almost all of the synthesized azodyes form good optical quality transparent amorphous films from volatile organic solvents with their light absorption in thin solid films in the range of 400-660 nm. Azocompounds with sterically small cyclohex-2-ene-1-ylidene fragment in their molecules proved to be most efficient materials for holographic data storage and nonlinear optics with diffraction efficiency up to 20.40%, self diffraction efficiency up to 12.94% and NLO coefficient d33 up to 125.7 pm/V. Azodyes with no additionally incorporated structural fragments and indene-1,3-dione electron acceptor group were least efficient materials for these purposes, however may show potential as photoactive components in organic solar cells due to their remarkable light absorption properties in the solid state.

  18. SYNTHESIS AND PROPERTIES OF A NEW AZOBENZENE SIDE-CHAIN POLYMER CONTAINING A TEMPO RADICAL

    Institute of Scientific and Technical Information of China (English)

    Yong Zhang; Ze-da Xu; Xing-he Fan; Xiao-fang Chen; Xin-hua Wan; Qi-feng Zhou

    2002-01-01

    To allow anisotropies of optical properties in a magnetic field, nitroxide radical is introduced into the ortho-position of the phenylene ring in the side chain. A new azobenzene side-chain polymer (TEMPO-PAZ) containing TEMPOradical was synthesized. The polymer has a good solubility in organic solvents. The ESR spectrum of the polymer indicatedthree absorption lines characteristic of TEMPO radical. The optical phase conjugated responses (I4) of the polymer filmswere investigated by degenerate four-wave mixing (DFWM). The experimental results showed that optical phase conjugatedresponse of the TEMPO-PAZ could be easily controlled by choosing the appropriate direction of magnetic field presumablydue to the nitroxide radical in the TEMPO-PAZ molecular structure. For the polymer investigated here, the nitroxide radicalwas introduced to increase optical phase conjugated response intensity in a magnetic field, aiming originally at searching fora new photo-active organic magnetic multifunctional materials.

  19. Fabrication of narrow surface relief features in a side-chain azobenzene polyester with a scanning near-field microscope

    DEFF Research Database (Denmark)

    Ramanujam, P.S.; Holme, N. C. R.; Pedersen, M.;

    2001-01-01

    We show that it is possible to fabricate topographic submicron features in a side-chain azobenzene polyester with a scanning near-field optical microscope, Through irradiation at a wavelength of 488 run at intensity levels of 12 W/cm(2), topographic features as narrow as 240 nm and as high as 6 nm...

  20. MORPHOLOGY STUDY OF A SERIES OF AZOBENZENE-CONTAINING SIDE-ON LIQUID CRYSTALLINE TRIBLOCK COPOLYMERS

    Institute of Scientific and Technical Information of China (English)

    Wei Deng; Annie Br(u)let; Pierre-antoine Albouy; Patrick Keller; Xiao-gong Wang; Min-hui Li

    2012-01-01

    A series of azobenzene containing side-on liquid crystalline ABA triblock copolymers were investigated.This triblock series possesses the same central liquid crystal block B and various lengths of the amorphous block A.Transmission electron microscopy (TEM),small angle X-rays and neutron scattering (SAXS and SANS) were used to study their morphologies.Aider annealing the samples over weeks at a temperature within the nematic temperature range of block B,different morphologies (disordered,lamellar,perforated layer and hexagonal cylinder) were observed by TEM.The alignment behavior of these azo triblock copolymers in the magnetic field for artificial muscle application,as well as the phase period and the order-disorder transition (ODT) were studied in situ by SANS.

  1. Azobenzene-functionalized cascade molecules

    DEFF Research Database (Denmark)

    Archut, A.; Vogtle, F.; De Cola, L.;

    1998-01-01

    Cascade molecules bearing up to 32 azobenzene groups in the periphery have been prepared from poly(propylene imine) dendrimers and N-hydroxysuccinimide esters. The dendritic azobenzene species show similar isomerization properties as the corresponding azobenzene monomers. The all-E azobenzene...

  2. Influence of the substituent on azobenzene side-chain polyester optical storage materials

    DEFF Research Database (Denmark)

    Pedersen, M; Hvilsted, Søren; Holme, NCR;

    1999-01-01

    , chloro, and bromo. C-13 NMR spectroscopic and molecular mass investigations substantiate good film forming characteristics. The optical storage performance of thin polyester films are investigated through polarization holography. The resulting diffraction efficiency is mapped and discussed as a function...... of irradiation power and exposure time. Polytetradecanedioates with cyano-, nitro-, methyl-, fluoro-, or trinuoromethyl-azobenzene reach more than 50% diffraction efficiency. Investigations of anisotropy induced at different temperatures reveal that the polyesters are only photosensitive in a narrow...

  3. Vibrational spectra study of phosphorus dendrimer containing azobenzene, ammonium and carbamate groups

    Science.gov (United States)

    Furer, V. L.; Vandyukov, A. E.; Majoral, J. P.; Caminade, A. M.; Kovalenko, V. I.

    2013-06-01

    The FTIR and FT Raman spectra of the first generation dendrimers, possessing carbamate (G1) or ammonium (G2) terminal groups were studied. The structural optimization and normal mode analysis were performed for dendrimers on the basis of the density functional theory (DFT). These calculations of G2 gave the frequencies of vibrations, infrared intensities and Raman scattering activities for the E- and Z-forms of azobenzene unit. The energy difference between the E- and Z-forms of G2 is 27.36 kcal/mol. The calculated geometrical parameters and harmonic vibrational frequencies are predicted in a good agreement with the experimental data. It was found that dendrimers molecules have a concave lens structure with planar -O-C6H4-CHdbnd N-N(CH3)Pdbnd S, and -O-C6H4-Ndbnd N-C6H4-CHdbnd N-NH-Cdbnd O-CH2-N fragments and slightly non-planar cyclotriphosphazene core. The experimental IR and Raman spectra of dendrimers G1 and G2 were interpreted by means of potential energy distributions. Relying on DFT calculations a complete vibrational assignment is proposed. The strong band 1605 cm-1 in the IR spectra show marked changes of the optical density in dependence of substituents in the aromatic ring. The differences in the IR and Raman spectra of G2 for the E- and Z-forms of azobenzene units were cleared up. During structural isomerization of azobenzene units, redistribution of band intensities appears to a much higher extent than frequency shifts.

  4. The effect of photoisomerization on the enzymatic hydrolysis of polymeric micelles bearing photo-responsive azobenzene groups at their cores.

    Science.gov (United States)

    Harnoy, Assaf J; Slor, Gadi; Tirosh, Einat; Amir, Roey J

    2016-06-28

    The design of stable polymeric micelles that can respond to specific stimuli is crucial for the development of smart micellar nanocarriers that can release their active cargo selectively at the target site, thus diminishing the therapeutic limitations due to non-selective damage to healthy tissues. Here we report the design and synthesis of photo- and enzyme-responsive amphiphilic PEG-dendron hybrids bearing one, two or four enzymatically cleavable azobenzene end-groups. These dual-responsive hybrids can respond to light through the reversible isomerization of the azobenzene end-groups from the non-polar trans isomer to the highly polar cis isomer and vice versa, upon UV and visible irradiation, respectively. The high structural precision of these hybrids, which emerges from the dendritic architecture, enabled a detailed study of the photoisomerization of the azobenzene end-groups with high molecular resolution. Remarkably, although the transition from trans-to-cis led to a significant increase in the polarity of the micellar cores, the micelles remained stable. Our kinetic studies show that although the trans isomer is a better substrate for the activating enzyme, the UV induced formation of the cis azobenzene end-groups led to significant acceleration of the enzymatic hydrolysis of the end-groups. These results provide strong indication that the enzyme cannot reach the core of the micelles and instead the end-groups have to leave the hydrophobic core in order to be exposed on the micelle's surface or even leave the micelle in order to allow their cleavage by the activating enzymes. PMID:27093537

  5. Photo-Induced Magnetic Anisotropy of Polymer Film Containing Azobenzene Organic Free Radical Group

    Institute of Scientific and Technical Information of China (English)

    徐则达; 张勇; 陈小芳; 范星河; 宛新华; 周其凤

    2003-01-01

    The forward degenerate four-wave mixing geometry was employed to induce microstructure in an organic free radical azobenzene polymer film. Before irradiated with Ar+ laser beams (λ = 514.5 nm), the azobenzene organic free radical polymer exhibits magnetic isotropic measured by superconducting quantum interference device. After photo-induced microstructure, the polymer film becomes magnetic anisotropy. When the applied magnetic field H = 50 Gauss, the magnetization along the normal direction of the polymer film is Mz = 5.5 × 10-5 emu/g,which is larger than Mx = 4.1 × 10-5 emu/g in the direction parallel to the polymer film.

  6. Mean-field theory of photoinduced formation of surface reliefs in side-chain azobenzene polymers

    DEFF Research Database (Denmark)

    Pedersen, Thomas Garm; Johansen, Per Michael; Holme, N.C.R.;

    1998-01-01

    A mean-field model of photoinduced surface reliefs in dye containing side-chain polymers is presented. It is demonstrated that photoinduced ordering of dye molecules subject to anisotropic intermolecular interactions leads to mass transport even when the intensity of the incident light is spatially...... uniform. Theoretical profiles are obtained using a simple variational method and excellent agreement with experimental surface reliefs recorded under various polarization configurations is found. The polarization dependence of both period and shape of the profiles is correctly reproduced by the model....

  7. PHOTOINDUCED BIREFRINGENCE AND NUMERICAL SOLUTION OF A NEW DYNAMIC MODEL IN AN AMORPHOUS COPOLYMER CONTAINING AZOBENZENE GROUPS

    Institute of Scientific and Technical Information of China (English)

    Ling-zhi Zhang; Zhi-gang Cai; Valerica Ninulescu; Ke Jin; Zhao-xi Liang

    2001-01-01

    Photoinduced birefringence is investigated in a new amorphous copolymer containing azobenzene groups. The levels of birefringence signal are found to depend on the polarization angle between the pump beam and the probe beam, and on the ellipticity of the pump beam. Both the growth and decay processes of the birefringence signal can be described by known biexponential equations. The rate constants and the amplitudes associated with the growth process of the photoinduced birefringence are observed to display a linear dependence with the pump beam intensity. A new dynamic model of the photoinduced birefringence is presented taking into account the contributions of both the trans and cis isomers ofazobenzene groups and the local polymer segments. The numerical treatment of this model shows good agreement with the experimental data in the whole writing-erasing processes of the photoinduced birefringence conducted in our polymer samples.

  8. Photo-aligned blend films of azobenzene-containing polyimides with and without side-chains for inducing inclined alignment of liquid crystal molecules

    Science.gov (United States)

    Usami, Kiyoaki; Sakamoto, Kenji

    2011-08-01

    We have succeeded in controlling the pretilt angle of liquid crystal (LC) molecules over the whole range of 0 to 90° by using photo-aligned blend films of two azobenzene-containing polyimides (Azo-PIs) with and without side-chains. The Azo-PIs were synthesized from pyromellitic dianhydride and a mixture of 4,4'-diaminoazobenzene and 4-(4'-propylbi(cyclohexan)-4-yl)phenyl 3,5-diaminobenzoate (PBCP-DABA). PBCP-DABA is a diamine to introduce a side-chain structure into the polyimide. Defect-free uniform LC alignment was obtained in the pretilt angle (θp) ranges of θp ≤ 11° and θp ≥ 78°. Previously, we reported that the pretilt angle can be controlled using pure photo-aligned films of Azo-PIs with different molar fractions of PBCP-DABA. For the pure photo-aligned films, the defect-free pretilt angle ranges were θp < 5° and θp ≥ 85°. These results suggest that the azimuthal anchoring strength of the blend Azo-PI film is stronger than that of the pure films of Azo-PIs with side-chains, at least for the pretilt angle range from 5 to 11°. We found that the defect-free pretilt angle range can be extended by using the blend Azo-PI films instead of the pure Azo-PI films.

  9. Supramolecular Phase-Selective Gelation by Peptides Bearing Side-Chain Azobenzenes: Effect of Ultrasound and Potential for Dye Removal and Oil Spill Remediation

    Directory of Open Access Journals (Sweden)

    Jürgen Bachl

    2015-05-01

    Full Text Available Phase selective gelation (PSG of organic phases from their non-miscible mixtures with water was achieved using tetrapeptides bearing a side-chain azobenzene moiety. The presence of the chromophore allowed PSG at the same concentration as the minimum gelation concentration (MGC necessary to obtain the gels in pure organic phases. Remarkably, the presence of the water phase during PSG did not impact the thermal, mechanical, and morphological properties of the corresponding organogels. In the case of miscible oil/water mixtures, the entire mixture was gelled, resulting in the formation of quasi-hydrogels. Importantly, PSG could be triggered at room temperature by ultrasound treatment of the mixture or by adding ultrasound-aided concentrated solution of the peptide in an oil-phase to a mixture of the same oil and water. Moreover, the PSG was not affected by the presence of salts or impurities existing in water from natural sources. The process could be scaled-up, and the oil phases (e.g., aromatic solvents, gasoline, diesel fuel recovered almost quantitatively after a simple distillation process, which also allowed the recovery and reuse of the gelator. Finally, these peptidic gelators could be used to quantitatively remove toxic dyes from aqueous solutions.

  10. Supramolecular phase-selective gelation by peptides bearing side-chain azobenzenes: effect of ultrasound and potential for dye removal and oil spill remediation.

    Science.gov (United States)

    Bachl, Jürgen; Oehm, Stefan; Mayr, Judith; Cativiela, Carlos; Marrero-Tellado, José Juan; Díaz, David Díaz

    2015-05-22

    Phase selective gelation (PSG) of organic phases from their non-miscible mixtures with water was achieved using tetrapeptides bearing a side-chain azobenzene moiety. The presence of the chromophore allowed PSG at the same concentration as the minimum gelation concentration (MGC) necessary to obtain the gels in pure organic phases. Remarkably, the presence of the water phase during PSG did not impact the thermal, mechanical, and morphological properties of the corresponding organogels. In the case of miscible oil/water mixtures, the entire mixture was gelled, resulting in the formation of quasi-hydrogels. Importantly, PSG could be triggered at room temperature by ultrasound treatment of the mixture or by adding ultrasound-aided concentrated solution of the peptide in an oil-phase to a mixture of the same oil and water. Moreover, the PSG was not affected by the presence of salts or impurities existing in water from natural sources. The process could be scaled-up, and the oil phases (e.g., aromatic solvents, gasoline, diesel fuel) recovered almost quantitatively after a simple distillation process, which also allowed the recovery and reuse of the gelator. Finally, these peptidic gelators could be used to quantitatively remove toxic dyes from aqueous solutions.

  11. Optically induced surface relief phenomena in azobenzene polymers

    DEFF Research Database (Denmark)

    Holme, NCR; Nikolova, Ludmila; Hvilsted, Søren;

    1999-01-01

    Azobenzene polymers and oligomers show intriguing surface relief features when irradiated with polarized laser light. We show through atomic force microscopic investigation of side-chain azobenzene polymers after irradiation through an amplitude mask that large peaks or trenches result depending ...... Institute of Physics....

  12. Polymer scaffolds bearing azobenzene - Potential for optical information storage

    DEFF Research Database (Denmark)

    Hvilsted, Søren; Ramanujam, P.S.

    2001-01-01

    The fundamental optical storage mechanism of the laser light addressable azobenzene moiety is briefly introduced. A modular and flexible synthesis design furnishes polyester matrices covalently integrating cyanoazobenzene in regularly spaced side chains. Thin films of these materials are particul...

  13. Photoinduced Deformation of Azobenzene Polyester Films

    DEFF Research Database (Denmark)

    Bublitz, D.; Helgert, M.; Fleck, B.;

    2000-01-01

    We investigate two types of azobenzene side-chain polyesters which have shown opposite behaviour in light-induced surface grating formation experiments. Thin films of these polymers prepared on a water surface undergo opposite changes of shape under the influence of polarized light. We propose...

  14. Holographic Gratings and Data Storage in Azobenzene-Containing Block Copolymers and Molecular Glasses

    Science.gov (United States)

    Audorff, Hubert; Kreger, Klaus; Walker, Roland; Haarer, Dietrich; Kador, Lothar; Schmidt, Hans-Werner

    This review covers synthesis, materials development, and photophysics of azobenzene-containing block copolymers as potential media for reversible volume holographic data storage. For high-density holographic data storage, volume gratings must be inscribed in millimeter-thick samples to achieve efficient angle multiplexing. It is demonstrated that block copolymers with azobenzene side-groups in the minority block develop no detrimental surface relief structures and exhibit superior performance regarding volume gratings, compared to homopolymers and statistical copolymers. Several material concepts for optimizing the refractive index modulation and the stability of volume gratings are presented. Stabilities of more than 2 years were achieved. Most important is the development of polymer blends comprising the azobenzene-containing block copolymer and an optically transparent homopolymer. This enables the preparation of millimeter-thick samples with the required optical density of ˜ 0. 7 at the writing wavelength by conventional injection molding techniques. The inscription of up to 200 holograms at the same lateral position was demonstrated. In addition, more than 1,000 write/erase cycles can be performed. This is the first time that the inscription and erasure of the long-term stable angle-multiplexed volume gratings in a rewritable polymeric medium have been achieved by purely optical means. A second important application for azobenzene-containing materials is the controlled preparation of surface relief structures. It is demonstrated that azobenzene-containing molecular glasses are an ideal class for efficient formation of surface relief gratings (SRGs) with amplitude heights of more than 600 nm. Clear relationships can be established between the chemical structure of the molecules and the behavior of SRG formation. All results are in agreement with the gradient force model by Kumar et al. The surface patterns are stable enough to be transferred to a polymer

  15. Weakening of a Polyethylene Chain by Methyl Side Groups

    NARCIS (Netherlands)

    Hageman, J.C.L.; Wijs, G.A. de; Groot, R.A. de; Meier, Robert J.

    2003-01-01

    The effect of methyl side groups on the strength of a single polyethylene chain is calculated with Density Functional Theory. Using transition state theory, the scission rate is calculated as function of stress for bonds next to a methyl side group. The increase in the scission rate due to the prese

  16. Synthesis of Poly (3-acetylpyrrolyl methine) with Azobenzene Side Groups and Study on Its Third-order Nonlinear Optical Property

    Institute of Scientific and Technical Information of China (English)

    Zhigang ZHANG; Hongcai WU; Lingjie MENG; Wenhui YI

    2005-01-01

    A novel soluble π-conjugated polymer, poly [(3-acetylpyrrole-2, 5-diyl) p-(N, N-dimethylamino) azobenzylidene] (PAPDMAABE), was synthesized by condensation of 3-acetylpyrrole with 4-aldehyde-4'-dimethylaminoazobenzene (ADMAA). The chemical structure of PAPDMAABE was characterized by Fourier transform infrared spectroscopy (FTIR),1H-NMR, and UV-Vis-NIR spectra. Transmission electron microscope (TEM) analysis for PAPDMAABE indicates that part of PAPDMAABE is in crystal state, due to the short-range order of the polymer. Thermogravimetric analysis (TGA) curve shows that the polymer has good thermal stability and its decomposition temperature is 248℃. The optical band gap of PAPDMAABE obtained from the optical absorption spectrum is about 1.73 eV. The resonant third-order nonlinear optical property of PAPDMAABE at 532 nm was studied using degenerate four-wave mixing (DFWM) technique.The resonant third-order nonlinear optical susceptibility of the polymer is about 7.48× 10-8 esu.

  17. DESIGN AND STUDY OF NEW AZOBENZENE LIQUID CRYSTAL/POLYMER MATERIALS

    Institute of Scientific and Technical Information of China (English)

    Yue Zhao

    2003-01-01

    Discussion is presented on the use of the photoisomerization of azobenzene chromophore in the design and preparation of novel functional materials. The two systems reviewed are azobenzene polymer-stabilized liquid crystals and azobenzene elastomers. In the first case, a polymer network containing azobenzene moieties is used to optically induce and stabilize a long-range liquid crystal orientation without the need of treating the surfaces of the substrates. This optical and rubbing-free approach was applied to nematic and ferroelectric liquid crystals. In the second case, an azobenzene side-chain liquid crystalline polymer is grafted onto a styrene-butadiene-styrene triblock copolymer to yield a photoactive thermoplastic elastomer. Coupled mechanical and optical effects make possible the formation of diffraction gratings that may be useful for mechanically tunable optical devices.

  18. Polarisation-sensitive optical elements in azobenzene polyesters and peptides

    DEFF Research Database (Denmark)

    Ramanujam, P.S.; Dam-Hansen, Carsten; Berg, Rolf Henrik;

    2006-01-01

    In this article, we describe fabrication of polarisation holographic optical elements in azobenzene polyesters. Both liquid crystalline and amorphous side-chain polyesters have been utilised. Diffractive optical elements such as lenses and gratings that are sensitive to the polarisation of the in...

  19. Laterally Mounted Azobenzenes on Platforms.

    Science.gov (United States)

    Hammerich, Melanie; Herges, Rainer

    2015-11-20

    Triazatriangulenium ions have previously been used as platforms to prepare self-assembled monolayers of functional molecules such as azobenzenes with vertical orientation and that are free-standing on gold surfaces. We have now prepared azobenzenes that are spanned between two posts which are attached on two platforms. Absorbed on a gold surface, the azobenzene should be laterally oriented at a distance of more than 4 Å above and thus electronically decoupled from the surface, and the system should perform a muscle-type movement upon isomerization. PMID:26551306

  20. Structure dependence of photochromism and thermochromism of azobenzene-functionalized polythiophenes

    Directory of Open Access Journals (Sweden)

    2007-07-01

    Full Text Available Two novel azobenzene-functionalized polythiophenes, poly[4-((4-(phenylazophenoxybutyl-3-thienylacetate] (P4 and the copolymer of 3-hexylthiophene and 4-((4-(phenylazophenoxybutyl-3-thienylacetate (COP64 have been synthesized. The structure dependence of photoluminescence features and thermochromic behaviors of both azobenzene-functionalized polymers was investigated. The results show that polymer structure has a strong influence on the conformation and optical properties of the resulting polythiophene derivatives. The photochemical control of photoluminescence property was achieved with homopolymer P4 using photoactive azobenzene side chains.

  1. Layer-by-layer deposited organic/inorganic hybrid multilayer films containing noncentrosymmetrically orientated azobenzene chromophores.

    Science.gov (United States)

    Kang, En-Hua; Bu, Tianjia; Jin, Pengcheng; Sun, Junqi; Yang, Yanqiang; Shen, Jiacong

    2007-07-01

    Organic/inorganic hybrid multilayer films with noncentrosymmetrically orientated azobenzene chromophores were fabricated by the sequential deposition of ZrO2 layers by a surface sol-gel process and subsequent layer-by-layer (LbL) adsorption of the nonlinear optical (NLO)-active azobenzene-containing polyanion PAC-azoBNS and poly(diallyldimethylammonium chloride) (PDDA). Noncentrosymmetric orientation of the NLO-active azobenzene chromophores was achieved because of the strong repulsion between the negatively charged ZrO(2) and the sulfonate groups of the azobenzene chromophore in PAC-azoBNS. Regular deposition of ZrO(2)/PAC-azoBNS/PDDA multilayer films was verified by UV-vis absorption spectroscopy and quartz crystal microbalance measurements. Both UV-vis absorption spectroscopy and transmission second harmonic generation (SHG) measurements confirmed the noncentrosymmetric orientation of the azobenzene chromophores in the as-prepared ZrO2/PAC-azoBNS/PDDA multilayer films. The square root of the SHG signal (I(2omega)(1/2)) increases with the increase of the azobenzene graft ratio in PAC-azoBNS as the number of deposition cycles of the ZrO(2)/PAC-azoBNS/PDDA films remains the same, while the second-order susceptibility chi(zzz)(2) of the film decreases with the increase of the azobenzene graft ratio. Furthermore, the present method was successfully extended to realize the noncentrosymmetric orientation of azobenzene chromophores in multilayer films when small organic azobenzene compounds with carboxylic acid and/or hydroxyl groups at one end and sulfonate groups at the other end were used. The present method was characterized by its simplicity and flexibility in film preparation, and it is anticipated to be a facile way to fabricate second-order nonlinear optical film materials. PMID:17555337

  2. The azobenzene optical storage puzzle - Demands on the polymer scaffold?

    DEFF Research Database (Denmark)

    Hvilsted, Søren; Ramanujam, P.S.

    2001-01-01

    The basic mechanism of optical information storage utilizing the azobenzene photoaddressable moiety will briefly be introduced. A synthetically flexible polyester matrix covalently integrating cyanoazobenzene in regularly spaced side chains is particularly well suited for holographic storage. Not...... materials, both copolymethacrylates and dendritic or hyperbranched polyesters provide some materials that exhibit liquid crystallinity. However, none of these other scaffolds offer materials that allow long-lasting anisotropy to be laser Light induced....

  3. The Azobenzene Optical Storage Puzzle - Demands on the Polymer Scaffold?

    DEFF Research Database (Denmark)

    Hvilsted, Søren; Ramanujam, PS

    2001-01-01

    The basic mechanism of optical information storage utilizing the azobenzene photoaddressable moiety will briefly be introduced. A synthetically flexible polyester matrix covalently integrating cyanoazobenzene in regularly spaced side chains is particularly well suited for holographic storage. Not...... materials, both copolymethacrylates and dendritic or hyperbranched polyesters provide some materials that exhibit liquid crystallinity. However, none of these other scaffolds offer materials that allow long-lasting anisotropy to be laser Light induced....

  4. Azobenzene dye-coupled quadruply hydrogen-bonding modules as colorimetric indicators for supramolecular interactions

    Directory of Open Access Journals (Sweden)

    Yagang Zhang

    2012-04-01

    Full Text Available The facile coupling of azobenzene dyes to the quadruply hydrogen-bonding modules 2,7-diamido-1,8-naphthyridine (DAN and 7-deazaguanine urea (DeUG is described. The coupling of azobenzene dye 2 to mono-amido DAN units 4, 7, and 9 was effected by classic 4-(dimethylaminopyridine (DMAP-catalyzed peptide synthesis with N-(3-dimethylaminopropyl-N’-ethyl carbodiimide hydrochloride (EDC as activating agent, affording the respective amide products 5, 8, and 10 in 60–71% yield. The amide linkage was formed through either the aliphatic or aromatic ester group of 2, allowing both the flexibility and absorption maximum to be tuned. Azobenzene dye 1 was coupled to the DeUG unit 11 by Steglich esterification to afford the product amide 12 in 35% yield. Alternatively, azobenzene dye 16 underwent a room-temperature copper-catalyzed azide–alkyne Huisgen cycloaddition with DeUG alkyne 17 to give triazole 18 in 71% yield. Azobenzene coupled DAN modules 5, 8, and 10 are bright orange–red in color, and azobenzene coupled DeUG modules 12 and 18 are orange–yellow in color. Azobenzene coupled DAN and DeUG modules were successfully used as colorimetric indicators for specific DAN–DeUG and DAN–UPy (2-ureido-4(1H-pyrimidone quadruply hydrogen-bonding interactions.

  5. Colorimetric Sugar Sensing Using Boronic Acid-Substituted Azobenzenes

    Directory of Open Access Journals (Sweden)

    Yuya Egawa

    2014-02-01

    Full Text Available In association with increasing diabetes prevalence, it is desirable to develop new glucose sensing systems with low cost, ease of use, high stability and good portability. Boronic acid is one of the potential candidates for a future alternative to enzyme-based glucose sensors. Boronic acid derivatives have been widely used for the sugar recognition motif, because boronic acids bind adjacent diols to form cyclic boronate esters. In order to develop colorimetric sugar sensors, boronic acid-conjugated azobenzenes have been synthesized. There are several types of boronic acid azobenzenes, and their characteristics tend to rely on the substitute position of the boronic acid moiety. For example, o-substitution of boronic acid to the azo group gives the advantage of a significant color change upon sugar addition. Nitrogen-15 Nuclear Magnetic Resonance (NMR studies clearly show a signaling mechanism based on the formation and cleavage of the B–N dative bond between boronic acid and azo moieties in the dye. Some boronic acid-substituted azobenzenes were attached to a polymer or utilized for supramolecular chemistry to produce glucose-selective binding, in which two boronic acid moieties cooperatively bind one glucose molecule. In addition, boronic acid-substituted azobenzenes have been applied not only for glucose monitoring, but also for the sensing of glycated hemoglobin and dopamine.

  6. Unusual photoanisotropic alignment in amorphous azobenzene polymers

    DEFF Research Database (Denmark)

    Ramanujam, P.S.

    2015-01-01

    It is well known that irradiation of azobenzene polymer films between 490 and 530nm results in alignment of molecules perpendicular to the polarization of the incident beam. I have recently found that irradiation of amorphous azobenzene polymers with linearly polarized light at wavelengths between...

  7. Induction of molecular chirality by circularly polarized light in cyclic azobenzene with a photoswitchable benzene rotor.

    Science.gov (United States)

    Hashim, P K; Thomas, Reji; Tamaoki, Nobuyuki

    2011-06-20

    New phototriggered molecular machines based on cyclic azobenzene were synthesized in which a 2,5-dimethoxy, 2,5-dimethyl, 2,5-difluorine or unsubstituted-1,4-dioxybenzene rotating unit and a photoisomerizable 3,3'-dioxyazobenzene moiety are bridged together by fixed bismethylene spacers. Depending upon substitution on the benzene moiety and on the E/Z conformation of the azobenzene unit, these molecules suffer various degrees of restriction on the free rotation of the benzene rotor. The rotation of the substituted benzene rotor within the cyclic azobenzene cavity imparts planar chirality to the molecules. Cyclic azobenzene 1, with methoxy groups at both the 2- and 5-positions of the benzene rotor, was so conformationally restricted that free rotation of the rotor was prevented in both the E and Z isomers and the respective planar chiral enantiomers were resolved. In contrast, compound 2, with 2,5-dimethylbenzene as the rotor, demonstrated the property of a light-controlled molecular brake, whereby rotation of the 2,5-dimethylbenzene moiety is completely stopped in the E isomer (brake ON, rotation OFF), while the rotation is allowed in the Z isomer (brake OFF, rotation ON). The cyclic azobenzene 3, with fluorine substitution on the benzene rotor, was in the brake OFF state regardless of E/Z photoisomerization of the azobenzene moiety. More interestingly, for the first time, we demonstrated the induction of molecular chirality in a simple monocyclic azobenzene by circular-polarized light. The key characteristics of cyclic azobenzene 2, that is, stability of the chiral structure in the E isomer, fast racemization in the Z isomer, and the circular dichroism of enantiomers of both E and Z isomers, resulted in a simple reversible enantio-differentiating photoisomerization directly between the E enantiomers. Upon exposure to r- or l-circularly polarized light at 488 nm, partial enrichment of the (S)- or (R)-enantiomers of 2 was observed. PMID:21567494

  8. Influence of UV irradiation on the blue and red light photoinduced processes in azobenzene polyesters

    DEFF Research Database (Denmark)

    Rodríguez, F.J.; Sánchez, C.; Villacampa, B.;

    2004-01-01

    Birefringence induced in a series of liquid crystalline side-chain azobenzene polyesters with different substituent groups was investigated under irradiation with 488 and 633 nm linearly polarized lights. Two different initial conditions have been used: the effect of a previous irradiation with UV...... light that yields the films into the isotropic state at room temperature (RT) was compared with the quenching from temperatures above the isotropic transition temperature Ti. UV–visible spectra of the thermally quenched films show the presence of aggregates when measured at RT. We have found that UV...... light irradiation creates a high concentration of cis isomers and breaks the aggregates, but they are formed again after a few days in dark at RT. Orientation of the chromophores perpendicular to the polarization of the 488 nm light and parallel to the polarization of the 633 nm light was confirmed...

  9. Steam Generator Group Project: Task 10, Secondary side examination

    International Nuclear Information System (INIS)

    This report concludes an effort to examine and assess from the secondary side, the condition of the retired-from-service Surry 2A steam generator. It is includes photographs of degradation of various components or regions in a generic recirculating type steam generator. The photographic detail given in the text (and the previous report NUREG/CR-3843, PNL-5033) have not been readily available to many investigators outside the Nuclear Steam Supply Vendors and Users. The photographs include views of Inconel 600 heat exchanger tubes (0.875 diameter [nominal] x 0.050 inch wall) showing deformed and intergranularly stress-corrosion cracked U-bends, tube denting in the support plate, intergranular attack and thinning (both in the tube sheet region), support plat deformation and cracking at flow slots and in ligaments between flow holes and tube holes. In addition, photographs of tube pitting, anti-vibration bar fretting, and the sludge pile are presented. An experimental stress analysis was conducted on a distorted Row 1 tube in the region of a compressed flow slot between the 6th and 7th (top) support plates. During removal of the tube, relaxation strains were measured and residual stresses calculated. Finally a cursory metallurgical failure analysis was conducted on a broken U-bend (R1C91) to determine its mode of failure. A rotabroach boring technique was used to make multiple penetrations with minimal damage to the secondary side, at various locations on the shell

  10. Preparation and Nonlinear Optical Property of Azobenzene Substituted Polyacetylene

    Institute of Scientific and Technical Information of China (English)

    Shou Chun YIN; Gang LI; Hong Yao XU; Ya Chen GAO; Yin Lin SONG

    2005-01-01

    Two new functional polyacetylenes bearing different azobenzene group, -{ HC=C[azo-N(CH3)CH2CH2OH] } n-, [poly(EHAB); azo = 4,4'-azobenzene] and - { HC=C[azo-N(CH3)CH2CH2OCOC3H7]}n-, [poly(EEAB)]} were prepared by [Rh(nbd)Cl]2-Et3N catalysts. Poly(EHAB) has poor solubility while poly(EEAB) can be dissolved in common solvent. The polymers were characterized by FTIR, 1H NMR, UV and GPC. The nonlinear optical property of the soluble poly(EEAB) was investigated with 8 ns width pulse at 532 nm by Z-scan technique. The results show that poly(EEAB) is endowed with the larger third-order nonlinear optical property.

  11. Synthesis and characterization of conjugated polymer containing azobenzene and oxadiazole units

    Institute of Scientific and Technical Information of China (English)

    Yue Zhang; Shi Jun Yu; Lu Wang; Cong Li

    2009-01-01

    A novel conjugated polymer containing azobenzene and oxadiazole units was synthesized through multi-step synthesis.The structures and properties of monomer and polymer were characterized and evaluated with IR,1H NMR,UV,TGA and GPC,respectively.Polymer with long side chain of alkoxy shows good solubility,thermal stability and photoisomerization property.

  12. Electrochemical and spectroelectrochemical studies of poly(2,5-di-2,3-dihydrothieno[3,4-b][1,4]dioxin-5-ylthienyl) derivatives bearing azobenzene, coumarine and fluorescein dyes: Effect of chromophore groups on electrochromic properties

    International Nuclear Information System (INIS)

    Three novel thiophene based monomers, 2,5-di-2,3-dihydrothieno[3,4-b][1,4]dioxin-5-ylthienyl derivatives, 1-{4-[(2,5-Di-2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl-3-thienyl) methoxy] phenyl}-2-phenyldiazene) (ETEAz), 4-[(2,5-Di-2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl-3-thienyl) methoxy]-2H-chromen-2-one) (ETECo) and methyl 2-{6-[(2,5-Di-2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl-3-thienyl) methoxy]-3-oxo-3H-xanthen -9-yl}benzoate (ETEFlo), were synthesized and their conducting polymers were electrochemically prepared on ITO glass electrodes for the first time. The electroactive monomers were functionalized with strong chromophore groups such as azobenzene, coumarine and fluorescein in order to investigate the effect of chromophore units on electrochemical and spectroelectrochemical characteristics of corresponding conducting polymers. Spectroelectrochemical studies demonstrated that combination of a strong chromophore group with polymer backbone leads to significant changes in electronic and optoelectronic behaviors of resulting conducting polymers. PETEAz, PETECo and PETEFlo exhibited multicolored electrochromism with three distinct states. PETEAz revealed 33% (565 nm) and 52% (1270 nm) transmittance changes (ΔT%), while PETECo exhibited 40% (535 nm) and 64% (1245 nm) at their dominant wavelenghts. The optical contrasts of PETEFlo were measured as 15% (495 nm), 28% (560 nm) and 43% (1345 nm), which were lower than those of PETEAz and PETEFlo. It was observed that all conducting polymer films could be very quickly switched between their neutral and oxidized states in both visible and NIR regions. Switching times values were found to be 0.3 s at 565 nm and 0.4 s at 1270 nm for PETEAz, 0.4 s at 535 nm and 0.5 s at 1245 nm for PETECo, 0.4 s at 495 nm, 0.4 s at 560 nm and 0.7 s at 1345 nm. Moreover, the optical band gap values for PETEAz, PETECo and PETEFlo were calculated as 1.6 eV, 1.4 eV and 1.55 eV, respectively, from the onset of π-π* transition in polymer films

  13. Local Density Fluctuations Predict Photoisomerization Quantum Yield of Azobenzene-Modified DNA.

    Science.gov (United States)

    Kingsland, Addie; Samai, Soumyadyuti; Yan, Yunqi; Ginger, David S; Maibaum, Lutz

    2016-08-01

    Azobenzene incorporated into DNA has a photoisomerization quantum yield that depends on the DNA sequence near the azobenzene attachment site. We use Molecular Dynamics computer simulations to elucidate which physical properties of the modified DNA determine the quantum yield. We show for a wide range of DNA sequences that the photoisomerization quantum yield is strongly correlated with the variance of the number of atoms in close proximity to the outer phenyl ring of the azobenzene group. We infer that quantum yield is controlled by the availability of fluctuations that enable the conformational change. We demonstrate that these simulations can be used as a qualitative predictive tool by calculating the quantum yield for several novel DNA sequences, and confirming these predictions using UV-vis spectroscopy. Our results will be useful for the development of a wide range of applications of photoresponsive DNA nanotechnology. PMID:27428569

  14. A Semiautomated Assignment Protocol for Methyl Group Side Chains in Large Proteins.

    Science.gov (United States)

    Kim, Jonggul; Wang, Yingjie; Li, Geoffrey; Veglia, Gianluigi

    2016-01-01

    The developments of biosynthetic specific labeling strategies for side-chain methyl groups have allowed structural and dynamic characterization of very large proteins and protein complexes. However, the assignment of the methyl-group resonances remains an Achilles' heel for NMR, as the experiments designed to correlate side chains to the protein backbone become rather insensitive with the increase of the transverse relaxation rates. In this chapter, we outline a semiempirical approach to assign the resonances of methyl-group side chains in large proteins. This method requires a crystal structure or an NMR ensemble of conformers as an input, together with NMR data sets such as nuclear Overhauser effects (NOEs) and paramagnetic relaxation enhancements (PREs), to be implemented in a computational protocol that provides a probabilistic assignment of methyl-group resonances. As an example, we report the protocol used in our laboratory to assign the side chains of the 42-kDa catalytic subunit of the cAMP-dependent protein kinase A. Although we emphasize the labeling of isoleucine, leucine, and valine residues, this method is applicable to other methyl group side chains such as those of alanine, methionine, and threonine, as well as reductively methylated cysteine side chains.

  15. trans-cis photoisomerization of azobenzene-conjugated dithiolato-bipyridine platinum(II) complexes: extension of photoresponse to longer wavelengths and photocontrollable tristability.

    Science.gov (United States)

    Sakamoto, Ryota; Kume, Shoko; Sugimoto, Manabu; Nishihara, Hiroshi

    2009-01-01

    Azobenzene derivatives modified with dithiolato-bipyridine platinum(II) complexes were synthesized, revealing their highly extended photoresponses to the long wavelength region as well as unique photocontrollable tristability. The absorptions of trans-1 and trans-2 with one azobenzene group on the dithiolene and bipyridine ligands, respectively, cover the range from 300 to 700 nm. These absorptions are ascribed, by means of time-dependent (TD)DFT calculations, to transitions from dithiolene(pi) to bipyridine(pi*), namely, interligand charge transfer (CT), pi-pi*, and n-pi* transitions of the azobenzene unit, and pi-pi* transitions of the bipyridine ligand. In addition, only trans-1 shows distinctive electronic bands, assignable to transitions from the dithiolene(pi) to azobenzene(pi*), defined as intraligand CT. Complex 1 shows photoisomerization behavior opposite to that of azobenzene: trans-to-cis and cis-to-trans conversions proceed with 405 and 312 nm irradiation, which correspond to excitation with the intraligand CT, and pi-pi* bands of the azobenzene and bipyridine units, respectively. In contrast, complex 2 shows photoisomerization similar to that of azobenzene: trans-to-cis and cis-to-trans transformations occur with 365 and 405 nm irradiation, respectively. Irradiation at 578 nm, corresponding to excitation of the interligand CT transitions, results in cis-to-trans conversion of both 1 and 2, which is the longest wavelength ever reported to effect the photoisomerization of the azobenzene group. The absorption and photochromism of 4, which has azobenzene groups on both the dithiolato and bipyridine ligands, have characteristics quite similar to those of 1 and 2, which furnishes 4 with photocontrollable tristability in a single molecule using light at 365, 405, and 578 nm. We also clarified that 1 and 2 have high photoisomerization efficiencies, and good thermal stability of the cis forms. Complexes 3 and 5 have almost the identical photoresponse to those

  16. Side-chain liquid crystalline polyesters for optical information storage

    DEFF Research Database (Denmark)

    Ramanujam, P.S.; Holme, Christian; Hvilsted, Søren;

    1996-01-01

    Azobenzene side-chain liquid crystalline polyester structures suitable for permanent optical storage are described. The synthesis and characterization of the polyesters together with differential scanning calorimetry and X-ray investigations are discussed. Optical anisotropic investigations and h...

  17. SYNTHESIS AND CHARACTERIZATION OF A NOVEL ALCOHOL-SOLUBLE POLYORGANOSILOXANE CONTAINING AMINO SIDE GROUPS

    Institute of Scientific and Technical Information of China (English)

    Chun-qing Liu; Yang Liu; Zhong-rong Shen; Ping Xie; Rong-ben Zhang; Chao-bin He; Tai-shung Chung

    2001-01-01

    A novel alcohol-soluble polyorganosiloxane containing amino side groups, poly[3-(4-aminophenoxy)propylmethylsiloxane] (2), was first prepared by the reduction of nitro groups on 4-nitrophenoxypropyl side chains of poly[3-(4-nitrophenoxy)propylmethylsiloxane] (1). The reaction proceeded easily with nearly 100% conversion. The synthesized alcohol-soluble polymer 2, which has potential application as a precursor for preparing advanced functional polymers, was characterized by FTI1R 1H-NMR, 13C-NMR, 29Si-NMR, VPO and GPC, respectively.

  18. UV gelation of single-component polyacrylates bearing dinitrobenzoate side groups.

    Science.gov (United States)

    Xie, Tongqing; Yang, Li; Sun, Xingxing; Jiang, Jun; Zhang, Xuepeng; Luo, Yi; Zhang, Guoqing

    2016-07-19

    Polyacrylates bearing dinitrobenzoate side groups undergo sol-gel-sol transformations in DMF or THF solutions regulated by alternating UV light and dark conditions. The formation and recombination of radical ionic species via photoinduced electron transfer may be responsible. PMID:27373563

  19. Conductance switching in a molecular device: The role of side groups and intermolecular interactions

    DEFF Research Database (Denmark)

    Taylor, Jeremy Philip; Brandbyge, Mads; Stokbro, Kurt

    2003-01-01

    We report first-principles studies of electronic transport in monolayers of Tour wires functionalized with different side groups. An analysis of the scattering states and transmission eigenchannels suggests that the functionalization does not strongly affect the resonances responsible for current...

  20. Graphene oxide catalyzed cis-trans isomerization of azobenzene

    Directory of Open Access Journals (Sweden)

    Dongha Shin

    2014-09-01

    Full Text Available We report the fast cis-trans isomerization of an amine-substituted azobenzene catalyzed by graphene oxide (GO, where the amine functionality facilitates the charge transfer from azobenzene to graphene oxide in contrast to non-substituted azobenzene. This catalytic effect was not observed in stilbene analogues, which strongly supports the existence of different isomerization pathways between azobenzene and stilbene. The graphene oxide catalyzed isomerization is expected to be useful as a new photoisomerization based sensing platform complementary to GO-based fluorescence quenching methods.

  1. Temperature- and Photocontrolled Unfolding/Folding of a Triple-Helical Azobenzene-Stapled Collagen Peptide Monitored by Infrared Spectroscopy.

    Science.gov (United States)

    Lorenz, Lisa; Kusebauch, Ulrike; Moroder, Luis; Wachtveitl, Josef

    2016-05-01

    The triple-helical structure of a model collagen peptide possessing azobenzene-derived clamps integrated in all three strands as side-chain-to-side-chain crosslinks is analyzed by IR spectroscopy in comparative thermal excursion experiments with the triple helix of a typical reference collagen peptide consisting of only glycine-proline-hydroxyproline repeats. By exploiting the known stabilizing effects of aqueous alcoholic solvents on the unique collagen fold, deuterated ethylene glycol/water (1:1) is used as a solvent to investigate the effect of the light-switchable trans/cis-azobenzene clamp on the stability of the triple helix in terms of H/D exchange rates and thermal unfolding. Results of this comparative analysis clearly reveal only a minor destabilization of the triple helix by the hydrophobic azobenzene moieties compared to the reference collagen peptide as reflected by a lower midpoint of the thermal unfolding and higher rates of H/D exchange. However, it also reveals that the driving force exerted by the trans-to-cis photoisomerization of the azobenzene moieties is insufficient for unfolding of the compact triple-helical collagen fold. Only temperature-dependent untightening of this fold with heating results in a reversible photomodulated unfolding and refolding of the azo-collagen peptide into the original triple helix. PMID:26918674

  2. Ferroelectric liquid-crystalline side group polymers - spacer length variation and comparison with the monomers

    OpenAIRE

    Kühnpast, Kurt; Springer, Jürgen; Scherowsky, Günter; Gießelmann, Frank; Zugenmaier, Peter

    1993-01-01

    The phase behaviour and the ferroelectric properties of liquid-crystalline side group polyacrylates containing an (R)-4''(1-methylheptyloxy)-4'-biphenylyloxycarbonyl-4-phenoxy moiety are compared with the properties of their monomers. A S*C phase polymorphism including monolayer and bilayer structures was found for the polymers. Some of the S*C subphases, consisting of smectic mono- or bi-layers, do not exhibit ferroelectric properties. These unusual properties do not exist for the correspond...

  3. Synthesis and characterization of new biodegradable thermosensitive polyphosphazenes with lactic acid ester and methoxyethoxyethoxy side groups

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Two novel biodegradable thermosensitive polyphosphazenes with lactic acid ester and methoxyethoxyethoxy side groups were synthesized via the macromolecular substitution reactions of poly(dichlorophosphazene) with the sodium salt of lactic acid ester and sodium methoxyethoxyethoxide.Their structures were confirmed by ~(31)p NMR,~1H NMR,~(13)C NMR,IR,DSC,and elemental analysis.The lower critical solution temperature(LCST) behavior in water and in vitro degradation property of the polymers was investigated....

  4. Cooperative Switching in Nanofibers of Azobenzene Oligomers

    Science.gov (United States)

    Weber, Christopher; Liebig, Tobias; Gensler, Manuel; Zykov, Anton; Pithan, Linus; Rabe, Jürgen P.; Hecht, Stefan; Bléger, David; Kowarik, Stefan

    2016-05-01

    Next-generation molecular devices and machines demand the integration of molecular switches into hierarchical assemblies to amplify the response of the system from the molecular level to the meso- or macro-scale. Here, we demonstrate that multi-azobenzene oligomers can assemble to form robust supramolecular nanofibers in which they can be switched repeatedly between the E- and Z-configuration. While in isolated oligomers the azobenzene units undergo reversible photoisomerization independently, in the nanofibers they are coupled via intermolecular interactions and switch cooperatively as evidenced by unusual thermal and kinetic behavior. We find that the photoisomerization rate from the Z-isomer to the E-isomer depends on the fraction of Z-azobenzene in the nanofibers, and is increased by more than a factor of 4 in Z-rich fibers when compared to E-rich fibers. This demonstrates the great potential of coupling individual photochromic units for increasing their quantum efficiency in the solid state with potential relevance for actuation and sensing.

  5. Ion-Exchange Membranes Based on Polynorbornenes with Fluorinated Imide Side Chain Groups

    Directory of Open Access Journals (Sweden)

    Arlette A. Santiago

    2012-01-01

    Full Text Available The electrochemical characteristics of cation-exchange membranes based on polynorbornenes with fluorinated and sulfonated dicarboximide side chain groups were reported. This study was extended to a block copolymer containing structural units with phenyl and 4-oxybenzenesulfonic acid, 2,3,5,6-tetrafluorophenyl moieties replacing the hydrogen atom of the dicarboximide group. A thorough study on the electrochemical characteristics of the membranes involving electromotive forces of concentration cells and proton conductivity is reported. The proton permselectivity of the membranes is also discussed.

  6. Synthesis of waterborne polyurethane containing alkoxysilane side groups and the properties of the hybrid coating films

    Science.gov (United States)

    Li, Qi; Guo, Longhai; Qiu, Teng; Xiao, Weidong; Du, Dianxing; Li, Xiaoyu

    2016-07-01

    A series of waterborne polyurethane (WPU) containing alkoxysilane side groups were synthesized by using the dihydroxy functionalized alkoxysilane. The diol with trimethoxysilane groups at the side chains was synthesized via Michael addition between 3-(methacryloxypropyl)trimethoxysilane (MAPTS) and diethanolamine (DEA). The silane diol was applied as the chain extender for the NCO-endcapped prepolymer of isophorone diisocyanate, polycarbonate diol, 2,2-bis(hydroxymethyl) butyric acid and 1,4-butanediol. The products with the silane content varied from 1.2 to 16.5 wt% were dispersed in water after neutralization. The effect of the silane diol on the particle size and morphology of the WPU dispersion was studied by dynamic light scattering (DLS) and transmission electron microscopy (TEM), respectively. X-ray photoelectron spectroscopy (XPS) characterization was carried out on the coating film of the WPU, revealing that the long flexible side chain is favorable for the silane components to emigrate toward the film surface and crosslink during the film formation process. As a result, both the surface contact angle to water and water adsorption of the WPU coating films increased with the silane content. Furthermore, the mechanical properties including the modulus and tensile strength of the films were also improved by the incorporation of silane diol.

  7. Cis-trans isomerisation of azobenzenes studied by laser-coupled NMR spectroscopy and DFT calculations.

    Science.gov (United States)

    Wazzan, Nuha A; Richardson, Patricia R; Jones, Anita C

    2010-07-30

    In a combined experimental and computational study of a group of para-substituted azobenzenes, the effects of substituents and solvent on the kinetics of thermal cis-to-trans isomerisation have been examined and the success of DFT calculations in predicting kinetic parameters assessed. Mono-substituted species are predicted to isomerise by inversion in both non-polar and polar solvent, whereas for push-pull azobenzenes the mechanism is predicted to change from inversion to rotation on going from non-polar to polar solvent. Computed free energies of activation qualitatively reproduce experimental trends but do not quantitatively predict the kinetics of cis-trans isomerisation. The polarisable continuum model of solvation fails to predict the experimentally observed influence of solvent on the entropy of activation.

  8. Preparation of a cationic azobenzene dye-montmorillonite intercalation compound and its photochemical behavior

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Montmorillonite/cationic azobenzene dye (GTL) intercalation compounds were prepared by the conventional ion exchange method. As compared with that of pure GTL, the thermal stability of the intercalated GTL was greatly enhanced, and the absorption band corresponding to azobenzene group in intercalated GTL shifted towards a longer wavelength by 55 nm, which could be ascribed to the strong conjugation of GTL supramolecular order structure (J cluster) confined in a nanoscale space of montmorillonite interlayer gallery. The microstructures of the resulting intercalation compounds could be successfully controlled by varying the amount of dye loaded as evidenced by the basal spacing of the intercalation compounds. The intercalated azo dye in the montmorillonite interlayer space exhibited reversible trans-to-cis photoisomerization and thermal cis-to-trans reaction. FTIR proved the successful intercalation of GTL into the silicate layer.

  9. Mechanized azobenzene-functionalized zirconium metal-organic framework for on-command cargo release

    Science.gov (United States)

    Meng, Xiangshi; Gui, Bo; Yuan, Daqiang; Zeller, Matthias; Wang, Cheng

    2016-01-01

    Stimuli-responsive metal-organic frameworks (MOFs) have gained increasing attention recently for their potential applications in many areas. We report the design and synthesis of a water-stable zirconium MOF (Zr-MOF) that bears photoresponsive azobenzene groups. This particular MOF can be used as a reservoir for storage of cargo in water, and the cargo-loaded MOF can be further capped to construct a mechanized MOF through the binding of β-cyclodextrin with the azobenzene stalks on the MOF surface. The resulting mechanized MOF has shown on-command cargo release triggered by ultraviolet irradiation or addition of competitive agents without premature release. This study represents a simple approach to the construction of stimuli-responsive mechanized MOFs, and considering mechanized UiO-68-azo made from biocompatible components, this smart system may provide a unique MOF platform for on-command drug delivery in the future. PMID:27493996

  10. Photodissociation UV-Vis Spectra of Cold Protonated Azobenzene and 4-(Dimethylamino)azobenzene and Their Benzenediazonium Cation Fragment.

    Science.gov (United States)

    Féraud, Géraldine; Dedonder-Lardeux, Claude; Jouvet, Christophe; Marceca, Ernesto

    2016-06-01

    Gas phase photodissociation electronic spectra of protonated azobenzene (ABH(+)) and 4-(dimethylamino)azobenzene (dmaABH(+)) were measured in a cryogenically cooled ion trap at temperatures of a few tens of Kelvin. Experimental results were complemented with electronic structure calculations in the ground state at the MP2/cc-pVDZ level of theory, and in the low lying excited states using the RI-CC2 method. Calculated energies revealed that only the trans isomers of the azonium molecular ions (protonation site on the azo group) will likely exist in the trap at the temperatures achieved in the experiment. The first transition of trans-ABH(+) is π* ← π, and the absorption band in the spectrum appears strongly red-shifted from that of the neutral molecule. The calculations showed that upon excitation the quasi-planar ground state (S0) transforms into a chairlike excited state (S1) by twisting the CNNC dihedral angle about 96°. A 41 cm(-1) active vibrational progression found in the ABH(+) spectrum may be associated with the twisting of the azo bond. Conversely, the electronic spectrum of dmaABH(+) exhibits a steep and unstructured S1 ← S0 absorption corresponding to a less distorted S1 state. The next two quasi-degenerate bands in the ABH(+) spectrum evidence sharper onsets and a charge transfer character. Using a second fragmentation laser and an additional He cooling pulse in the trap, it was possible to measure the UV spectrum of cold benzenediazonium fragments. PMID:27216229

  11. Photochemical properties of multi-azobenzene compounds.

    Science.gov (United States)

    Bahrenburg, Julia; Sievers, Claudia M; Schönborn, Jan Boyke; Hartke, Bernd; Renth, Falk; Temps, Friedrich; Näther, Christian; Sönnichsen, Frank D

    2013-03-01

    A systematic study is reported of the photochemical properties of the multi-azobenzene compounds bis[4-(phenylazo)phenyl]amine (BPAPA) and tris[4-(phenylazo)phenyl]amine (TPAPA) compared to the parent molecule 4-aminoazobenzene (AAB). The bis- and tris-azobenzenes were synthesised by a variant of the Ullmann reaction and exist in their stable all-E forms at room temperature. Striking changes in the spectral positions and intensities of their first ππ* absorption bands compared to AAB reveal strong electronic coupling between the AB units. The nature of the excited states was explored by quantum chemical calculations at the approximate coupled-cluster (CC2) level. Upon UV/VIS irradiation, the molecules isomerise to the Z-isomer (AAB), ZE- and ZZ-isomers (BPAPA), and ZEE-, ZZE- and ZZZ-isomers (TPAPA), respectively. The photoswitching behaviours were investigated by UV/VIS and NMR spectroscopies. All individual isomers were detected by one-dimensional (1D) (1)H NMR spectroscopy (BPAPA) and two-dimensional (2D) HSQC NMR spectroscopy (TPAPA). A kinetic analysis provided the isomer-specific thermal lifetimes. The variance of the thermal lifetimes demonstrates a dependence of the Z-E isomerisation on the chromophore size and number of AB units. PMID:23224342

  12. Biphotonic holographic gratings in azobenzene polyesters: Surface relief phenomena and polarization effects

    DEFF Research Database (Denmark)

    Sánchez, C.; Alcalá, R.; Hvilsted, Søren;

    2000-01-01

    Biphotonic holographic gratings have been recorded in a side-chain azobenzene liquid crystalline polyester using a blue incoherent source and a He-Ne laser. Intensity gratings and the appearance of surface relief have been observed when two linearly polarized beams from a He-Ne laser are made to ...... to interfere on a film illuminated with blue light. Polarized holographic gratings are also created with two orthogonally circularly polarized He-Ne beams. All these gratings are stable in darkness but can be erased with blue light. (C) 2000 American Institute of Physics....

  13. Polystyrene Backbone Polymers Consisting of Alkyl-Substituted Triazine Side Groups for Phosphorescent OLEDs

    Directory of Open Access Journals (Sweden)

    Beatrice Ch. D. Salert

    2012-01-01

    Full Text Available This paper describes the synthesis of new electron-transporting styrene monomers and their corresponding polystyrenes all with a 2,4,6-triphenyl-1,3,5-triazine basic structure in the side group. The monomers differ in the alkyl substitution and in the meta-/paralinkage of the triazine to the polymer backbone. The thermal and spectroscopic properties of the new electron-transporting polymers are discussed in regard to their chemical structures. Phosphorescent OLEDs were prepared using the obtained electron-transporting polymers as the emissive layer material in blend systems together with a green iridium-based emitter 13 and a small molecule as an additional cohost with wideband gap characteristics (CoH-001. The performance of the OLEDs was characterized and discussed in regard to the chemical structure of the new electron-transporting polymers.

  14. Optical Input/Electrical Output Memory Elements based on a Liquid Crystalline Azobenzene Polymer.

    Science.gov (United States)

    Mosciatti, Thomas; Bonacchi, Sara; Gobbi, Marco; Ferlauto, Laura; Liscio, Fabiola; Giorgini, Loris; Orgiu, Emanuele; Samorì, Paolo

    2016-03-01

    Responsive polymer materials can change their properties when subjected to external stimuli. In this work, thin films of thermotropic poly(metha)acrylate/azobenzene polymers are explored as active layer in light-programmable, electrically readable memories. The memory effect is based on the reversible modifications of the film morphology induced by the photoisomerization of azobenzene mesogenic groups. When the film is in the liquid crystalline phase, the trans → cis isomerization induces a major surface reorganization on the mesoscopic scale that is characterized by a reduction in the effective thickness of the film. The film conductivity is measured in vertical two-terminal devices in which the polymer is sandwiched between a Au contact and a liquid compliant E-GaIn drop. We demonstrate that the trans → cis isomerization is accompanied by a reversible 100-fold change in the film conductance. In this way, the device can be set in a high- or low-resistance state by light irradiation at different wavelengths. This result paves the way toward the potential use of poly(metha)acrylate/azobenzene polymer films as active layer for optical input/electrical output memory elements.

  15. Photo Induced Membrane Separation for Water Purification and Desalination Using Azobenzene Modified Anodized Alumina Membranes.

    Science.gov (United States)

    Fujiwara, Masahiro; Imura, Tatsuki

    2015-06-23

    Water purification and desalination to produce end-use water are important agendas in 21st century, because the global water shortage is becoming increasingly serious. Those processes using light energy, especially solar energy, without the consumption of fossil fuels are desired for creating sustainable society. For these earth-friendly water treatments, nanoporous materials and membranes are expected to provide new technologies. We have reported before that the repetitive photo isomerization of azobenzene groups between the trans and cis isomers induced by the simultaneous irradiation of UV and visible lights accelerates the molecular movement of nearby molecules in nanoporous materials. After further studies, we recently found that the permeation of water through azobenzene modified anodized alumina membranes as a photo responsive nanoporous membrane was achieved by the simultaneous irradiation of UV and visible lights, while no water penetration occurred under no light, only single UV or visible light. The photo induced permeation of water was promoted by the vaporization of water with the repetitive photo isomerization of azobenzene. This membrane permeation achieved the purification of water solutions, because dye molecules and a protein dissolved in aqueous solutions were not involved in the photo induced penetrated water. When 3.5% of sodium chloride solution as model seawater was employed for this membrane separation, the salt content of the permeated water was less than 0.01% to accomplish the complete desalination of seawater. PMID:26005901

  16. Optical Input/Electrical Output Memory Elements based on a Liquid Crystalline Azobenzene Polymer.

    Science.gov (United States)

    Mosciatti, Thomas; Bonacchi, Sara; Gobbi, Marco; Ferlauto, Laura; Liscio, Fabiola; Giorgini, Loris; Orgiu, Emanuele; Samorì, Paolo

    2016-03-01

    Responsive polymer materials can change their properties when subjected to external stimuli. In this work, thin films of thermotropic poly(metha)acrylate/azobenzene polymers are explored as active layer in light-programmable, electrically readable memories. The memory effect is based on the reversible modifications of the film morphology induced by the photoisomerization of azobenzene mesogenic groups. When the film is in the liquid crystalline phase, the trans → cis isomerization induces a major surface reorganization on the mesoscopic scale that is characterized by a reduction in the effective thickness of the film. The film conductivity is measured in vertical two-terminal devices in which the polymer is sandwiched between a Au contact and a liquid compliant E-GaIn drop. We demonstrate that the trans → cis isomerization is accompanied by a reversible 100-fold change in the film conductance. In this way, the device can be set in a high- or low-resistance state by light irradiation at different wavelengths. This result paves the way toward the potential use of poly(metha)acrylate/azobenzene polymer films as active layer for optical input/electrical output memory elements. PMID:26890532

  17. Controlling Miscibility in Polyethylene-Polynorbornene Block Copolymers via Side-Group Chemistry

    Science.gov (United States)

    Mulhearn, William; Register, Richard

    Block copolymers containing a crystallizable block, such as polyethylene (PE), and an amorphous block with high glass transition temperature (Tg) are an interesting class of materials since the rigid glassy block can improve the mechanical response of the article under strain by reinforcing the crystal fold surface. However, to prepare an easily processable PE-containing block copolymer it is necessary to avoid microphase separation in the melt by selection of amorphous blocks with weak repulsive interactions against PE (low Flory interaction parameter χ or interaction energy density X) . Most such low- χ polymers are chemically similar to PE, such as copolymers of ethylene and a small amount of an α-olefin, and therefore exhibit similarly low glass transition temperatures. This work investigates a series of low- and high-Tg polymers based on substituted norbornene monomers, polymerized via ring-opening metathesis polymerization (ROMP). Hydrogenated polynorbornene derivatives possess a wide range of glass transition temperatures, and miscibility with PE can be readily tuned by the choice of substituents on the monomers (e.g. aromatic vs. aliphatic groups). Two species investigated, hydrogenated poly(cyclohexyl norbornene) and hydrogenated poly(norbornyl norbornene), have high Tg and also remain miscible with polyethylene to high molecular weight. Furthermore, we develop a set of mixing rules to qualitatively predict the solubility behavior of substituted ROMP polynorbornenes as a function of their side-groups.

  18. Calculated photo-isomerization efficiencies of functionalized azobenzene derivatives in solar energy materials: azo-functional organic linkers for porous coordinated polymers

    International Nuclear Information System (INIS)

    Recently, we used a local orbital density functional theory code called FIREBALL, to study the photoisomerization process in azobenzene derivatives for solar energy materials. Azobenzene functional groups undergo photoisomerization upon light irradiation or application of heat. Zhou et al (2012 J. Am. Chem. Soc. 134 99–102) showed that these azobenzenes can then be introduced into metal–organic frameworks via an organic linker in order to create a reversible switch for CO2 adsorption. In this manuscript, we examined how the addition of organic linkers (isophthalic acid) changes the relaxation times, isomerization mechanism, and quantum yield for both the cis↔trans pathways. We then tuned these properties by substituting functional groups, finding an increase in quantum yield as well as improved optical properties. (paper)

  19. A project by the SIDeMaST Immunopathology Group on cutaneous vasculitis.

    Science.gov (United States)

    Papini, M; Quaglino, P; La Placa, M; Marzano, A V

    2015-04-01

    Vasculitides are a challenge to the clinician, in terms of both diagnosis and therapy. Multiple classification systems have been implemented and the numerous classification schemes reflect the complexity of establishing a simple classification that could be functional for daily care. Although vasculitis classification has become increasingly elaborated, some areas remain ill defined. Some forms of vasculitis are still difficult to assign to a specific disease entity. Generally accepted operational criteria are available for many vasculitides, but for some entities there are no effective criteria. Moreover, diagnostic criteria for vasculitis with sufficient strength and/or confidence that can be universally accepted are not yet available. The need for diagnostic criteria validated and agreed upon is particularly relevant in the context of cutaneous vasculitis. The project of the SIDeMaST Italian Group of Immunopathology on cutaneous vasculitis is a national prospective observational study designed to develop and validate diagnostic criteria and to improve and validate classification criteria for cutaneous small vessel vasculitis also known as leukocytoclastic vasculitis (CLV). Primary objective of the study will also be that of developing the CUtaneous VAsculitis Severity Index (CUVASI). Secondary objectives of the project will be: 1) definition of the etiological agents that are most frequently associated with CLV; 2) search for possible correlations between causative agent and peculiar clinical and/or histopathological aspects; 3) evaluation of immunofluorescence pattern observed in this specific group of primitive cutaneous vasculitis in order to characterize the diagnostic sensitivity and specificity of this technique; 4) identification of a set of clinical investigations and laboratory tests to be performed for a correct CLV assessment. Actually 15 Italian dermatological clinics are contributing to the project and anticipated recruiting >100 patients with CLV

  20. Spectral Characteristics of Bent-Core Azobenzen Monomers%含偶氮基团的弯曲型分子的光谱特性研究

    Institute of Scientific and Technical Information of China (English)

    董寅; 沈冬; 郑致刚

    2012-01-01

    The azo (-N =N-) linkage has the particular thermochemistry and actinoche-mistry behavior, the azobenzene group can undergo reversible cis-trans isomerization under light irradiation and its nonlinear optical properties possess the potential applications in the aspects of molecular design, photofixation, photochromics, thermochromism, etc. The UV-Vis absorbance of sixteen bent-core or linear monomers containing azobenzene as side arms and substituted para/m-aminobenzoic acid as central units was studied. The angle of the bent-core molecules was simulated. The trans-form of azo compounds showed a strong band in the UV region (330~370 nm) and a weak band at 440~450 nm. It was found that it has a close relationship between the angle of the molecules and the UV-Vis absorption.%偶氮连接基团(-N=N-)有着特殊的热化学和光化学行为,在适当波长光的照射下,能发生可逆的顺反异构反应,从而发生吸收波长的变化.在分子设计、光定位、光致变色和热致变色等方面,偶氮连接基团的非线性光化学性质都有着潜在的应用价值.文章以含有偶氮基作为侧翼的弯曲型分子作为研究对象,比较了弯曲型和直线型分子的吸收光谱;并用计算机模拟计算了弯曲型分子的角度,发现分子弯曲角和紫外可见吸收光谱存在着密切的关系.

  1. A Dynamic Combinatorial Approach for Identifying Side Groups that Stabilize DNA-Templated Supramolecular Self-Assemblies

    Directory of Open Access Journals (Sweden)

    Delphine Paolantoni

    2015-02-01

    Full Text Available DNA-templated self-assembly is an emerging strategy for generating functional supramolecular systems, which requires the identification of potent multi-point binding ligands. In this line, we recently showed that bis-functionalized guanidinium compounds can interact with ssDNA and generate a supramolecular complex through the recognition of the phosphodiester backbone of DNA. In order to probe the importance of secondary interactions and to identify side groups that stabilize these DNA-templated self-assemblies, we report herein the implementation of a dynamic combinatorial approach. We used an in situ fragment assembly process based on reductive amination and tested various side groups, including amino acids. The results reveal that aromatic and cationic side groups participate in secondary supramolecular interactions that stabilize the complexes formed with ssDNA.

  2. Preparation and characterization of highly cross-linked polyimide aerogels based on polyimide containing trimethoxysilane side groups.

    Science.gov (United States)

    Pei, Xueliang; Zhai, Wentao; Zheng, Wenge

    2014-11-11

    In this study, highly cross-linked and completely imidized polyimide aerogels were prepared from polyimide containing trimethoxysilane side groups, which was obtained as the condensation product of polyimide containing acid chloride side groups and 3-aminopropyltrimethoxysilane. After adding water and acid catalyst, the trimethoxysilane side groups hydrolyzed and condensed one another, and a continuous increase in the complex viscosities of the polyimide solutions with time was observed. The formed polyimide gels were dried by freeze-drying from tert-butyl alcohol to obtain polyimide aerogels, which consisted of a three-dimensional network of polyimide fibers tangled together. By varying the solution concentration of the polyimide containing trimethoxysilane side groups, polyimide aerogels with different densities (ranging from 0.19 to 0.42 g/cm(3)) were obtained. The resulting polyimide aerogels had small pore diameter (ranging from 20.7 to 58.3 nm), high surface area (ranging from 310 to 344 m(2)/g), high 5% weight loss temperature in air (at about 440 °C), and an excellent mechanical property. In addition, the glass transition temperature (349 °C) of the polyimide aerogels was much higher than that (210 °C) of the corresponding linear polyimide. So, even after being heated at 300 °C for 30 min, the porous structure of the polyimide aerogels was not completely destroyed. PMID:25340747

  3. Dynamics of Azobenzene Dimer Photoisomerization: Electronic and Steric Effects.

    Science.gov (United States)

    Titov, Evgenii; Granucci, Giovanni; Götze, Jan Philipp; Persico, Maurizio; Saalfrank, Peter

    2016-09-15

    While azobenzenes readily photoswitch in solution, their photoisomerization in densely packed self-assembled monolayers (SAMs) can be suppressed. Reasons for this can be steric hindrance and/or electronic quenching, e.g., by exciton coupling. We address these possibilities by means of nonadiabatic molecular dynamics with trajectory surface hopping calculations, investigating the trans → cis isomerization of azobenzene after excitation into the ππ* absorption band. We consider a free monomer, an isolated dimer and a dimer embedded in a SAM-like environment of additional azobenzene molecules, imitating in this way the gradual transition from an unconstrained over an electronically coupled to an electronically coupled and sterically hindered, molecular switch. Our simulations reveal that in comparison to the single molecule the quantum yield of the trans → cis photoisomerization is similar for the isolated dimer, but greatly reduced in the sterically constrained situation. Other implications of dimerization and steric constraints are also discussed. PMID:27542538

  4. Genotoxicity of a variety of azobenzene and aminoazobenzene compounds in the hepatocyte/DNA repair test and the Salmonella/mutagenicity test.

    Science.gov (United States)

    Mori, H; Mori, Y; Sugie, S; Yoshimi, N; Takahashi, M; Ni-i, H; Yamazaki, H; Toyoshi, K; Williams, G M

    1986-04-01

    Genotoxicity of 39 azo dye compounds of azobenzenes, aminoazobenzenes, and diaminoazobenzenes was examined in the hepatocyte primary culture/DNA repair test. Azobenzene (AzB) and 3,3'- or 4,4'-substituted azobenzenes such as (CH3)2AzB, (CH2OH)2AzB, (CH2OCOCH3)2AzB, and (CH2Cl)2AzB did not generate DNA repair, indicating lack of genotoxicity of these compounds. In contrast, all of 24 aminoazobenzenes, including those of unknown carcinogenicity, i.e., 3'-methyl-4-aminoazobenzene, 3'-CH2OH-aminoazobenzene, 3'-hydroxymethyl-N-methyl-4-aminoazobenzene, 3'-COOH-methylaminoazobenzene, 4'-formyl-N,N-dimethyl-4-aminoazobenzene, 3'-CH2Cl-dimethylaminoazobenzene, 4'-CH2Cl-dimethylaminoazobenzene, and 2'-, 3'-, or 4'-CH2OCOCH3-dimethylaminoazobenzene, elicited DNA repair synthesis. A positive DNA repair response was obtained for the 3 of 6 tested diaminoazobenzenes, i.e., N'-acetyl-N'-methyl-4-amino-dimethylaminoazobenzene, N'-acetyl-N'-methyl-4-amino-methylaminoazobenzene, and N'-acetyl-N'-methyl-4-amino-N-acetyl-methylaminoazobenzene, which are known to be carcinogenic. These results indicate that the amino group is functional for the expression of genotoxicity of azobenzene compounds. Twenty-one azobenzenes of these 3 classes were also examined for their mutagenicity in the Salmonella/mutagenicity assay. These results were almost identical with those of the DNA repair test except for several azo dyes such as AzB and 4,4'-(CH2Oacetyl)2AzB of the azobenzenes and N'-acetyl-4-amino-dimethylaminoazobenzene and N'-acetyl-N-methyl-4-amino-N-acetyl methylaminoazobenzene of the diaminoazobenzenes.

  5. The Volume Holographic Optical Storage Potential in Azobenzene Containing Polymers

    DEFF Research Database (Denmark)

    Hvilsted, Søren; Sanchez, Carlos; Alcalá, Rafael

    2009-01-01

    Volume holographic data storage is one of the most promising techniques to improve both the storage capacity of devices and the transfer data rate. Among the materials proposed as storage data media, azobenzene containing polymers have received much attention. Some of their properties seem...... to be suitable for holographic storage applications. However, they still present several problems, mainly those related with light sensitivity, response time and stability of the stored information. In this article we review the work performed on volume holographic storage using azobenzene containing polymers...

  6. Photo-induced fluorescence emission enhancement of azobenzene thin films

    OpenAIRE

    Haruta, Osamu; Matsuo, Yasutaka; Ijiro, Kuniharu

    2008-01-01

    UV irradiation-induced fluorescence enhancement of thin films composed of azobenzene amphiphiles, C12AzoC10N+ (AzoN+), was investigated. UV irradiation to Langmuir-Blodgett (LB) monolayers of AzoN+ indicated that the fluorescence emission from an irradiated area was enhanced and the emission was independent of the aggregation structures of an azobenzene moiety. Moreover, UV irradiation to cast films of AzoN+ revealed that the enhancement was increased by increasing the irradiation time. The f...

  7. Collective narcissism and intergroup hostility: the dark side of 'in group love'.

    OpenAIRE

    Golec de Zavala, Agnieszka

    2011-01-01

    This paper addresses the relationship between ‘in-group love’ and ‘out-group hate’ and integrates findings of psychology of intergroup relations with findings regarding psychological outcomes of narcissism. It reviews current research on intergroup consequences of collective narcissism – an emotional investment in an unrealistic belief in exaggerated greatness of an in-group - which indicates that the differentiation between narcissistic and genuine positive group regard uncovers the potentia...

  8. Vibrational spectra study of phosphorus dendrimer containing azobenzene units on the surface

    Science.gov (United States)

    Furer, V. L.; Vandyukov, A. E.; Majoral, J. P.; Caminade, A. M.; Kovalenko, V. I.

    2013-08-01

    The FTIR and FT Raman spectra of the first generation dendrimers, possessing oxybenzaldehyde (G1) or oxyphenylazobenzaldehyde (G2) terminal groups and sodium 4-[4-oxyphenyl)azo]-benzaldehyde (SOAB) were studied. The structural optimization and normal mode analysis were performed for dendrimer G2 on the basis of the density functional theory (DFT). These calculations gave the frequencies of vibrations, infrared intensities and Raman scattering activities for the E- and Z-forms of azobenzene unit. The energy differences between the E- and Z-forms are 12.62 and 25.16 kcal/mol for SOAB and G2. The calculated in gas phase dipole moments for the E- and Z-forms are equal to 20.86, 18.28 D (SOAB) and 7.56, 8.88 D (G2). The calculated geometrical parameters and harmonic vibrational frequencies are predicted in a good agreement with the experimental data. It was found that dendrimer G2 molecule has a concave lens structure with planar sbnd Osbnd C6H4sbnd CHdbnd Nsbnd N(CH3)Pdbnd S and sbnd Osbnd C6H4sbnd Ndbnd Nsbnd C6H4sbnd CHdbnd O fragments and slightly non-planar cyclotriphosphazene core. The experimental IR and Raman spectra of dendrimer G2 were interpreted by means of potential energy distributions. Relying on DFT calculations a complete vibrational assignment is proposed. The strong band 1598 cm-1 in the IR spectra show marked changes of the optical density in dependence of substituents in the aromatic ring. The differences in the IR and Raman spectra of SOAB and G2 for the E- and Z-forms of azobenzene units were cleared up. During structural isomerization of azobenzene units, redistribution of band intensities appears to a much higher extent than frequency shifts.

  9. Propargyloxycarbonyl as a protecting group for the side chains of serine, threonine and tyrosine

    Indian Academy of Sciences (India)

    Ramapanicker Ramesh; Kavita De; Shipra Gupta; Srinivasan Chandrasekaran

    2008-01-01

    Propargyloxycarbonyl group is used as a protecting group for the hydroxyl groups of serine, threonine and tyrosine. The propargyloxycarbonyl derivatives of these hydroxy amino acids are stable to acidic and basic reagents commonly employed in peptide synthesis. The deprotection of the -Poc derivatives using tetrathiomolybdate does not affect commonly used protecting groups such as -Boc, -Cbz, -Fmoc, methyl and benzyl esters. The di- and tripeptides synthesized using -Poc derivatives of serine, threonine and tyrosine are stable, isolable compounds and give the hydroxy peptides in good yields when treated with tetrathiomolybdate.

  10. Pattern Formation and Quasicrystal Structure in Azobenzene Polymer Film

    Institute of Scientific and Technical Information of China (English)

    XU Ze-Da; CAI Zhi-Gang; ZHANG Ling-Zhi; LIU Yan-Fa; YANG Jie; SHE Wei-Long; ZHOU Jian-Ying

    2000-01-01

    Pattern formation in azobenzene polymer film by degenerate four-wave mixing is reported. Island arrays with specific patterns are analyzed with scanning electron microscopy and polarizing optical microscopy. It is demonstrated that the control of photo-induced nanostructure sized micropattern in the nonlinear organic film is possible by using properly polarized writing beams with the total incident power exceeding a certain threshold.

  11. The Effect of Dissolved Side-Group Polymers on Pattern Dynamics in Nematic Liquid Crystals in a Rotating Magnetic Field

    OpenAIRE

    Pashkovsky, E.; Stille, W; Strobl, G.; Talebi, D.

    1997-01-01

    Patterns formed by inversion walls in nematic layers exposed to a rotating magnetic field were studied. Dilute solutions of a mesogenic side group polymethacrylate in a low molecular weight liquid crystal (5CB) were used in comparison with the pure solvent. As found in a previous work, in this system the intensity of backflow (fluid flow induced by director rotation) can be controlled by the polymer concentration due to a specific increase of shear viscosity coefficients. In the synchronous r...

  12. Understanding the effect of side groups in ionic liquids on carbon-capture properties: a combined experimental and theoretical effort

    OpenAIRE

    Yan, Fangyong; Lartey, Michael; Damodaran, Krishnan; Albenze, Erik; Thompson, Robert L.; Kim, Jihan; Haranczyk, Maciej; Nulwala, Hunaid B.; Luebke, David R.; Smit, Berend

    2013-01-01

    Ionic liquids are an emerging class of materials with applications in a variety of fields. Steady progress has been made in the creation of ionic liquids tailored to specific applications. However, the understanding of the underlying structure-property relationships has been slower to develop. As a step in the effort to alleviate this deficiency, the influence of side groups on ionic liquid properties has been studied through an integrated approach utilizing synthesis, experimental determinat...

  13. The synthesis and characterization of organometallic copolymers with Mn-Re binuclear transition-metal group in the side chain

    Institute of Scientific and Technical Information of China (English)

    XU Zhi; FENG Gang; BAI Zhifeng; MA Yongqiang; CHANG Weixing; LI Jing

    2006-01-01

    Novel organometallic copolymers with Mn-Re binuclear transition-metal groups in the side chain are synthesized and characterized. The structure and properties of the copolymers are characterized by GPC, DSC, TG, NMR, FT-IR, UV-Vis spectra and elemental analysis. The glass transition temperature and UV-Vis spectra properties of these three organometallic copolymers are found to be different from the normal polystyrene. New synthetic strategy for the synthesis of organometallic copolymer is developed.

  14. Experimental design for one-sided confidence intervals or hypothesis tests in binomial group testing

    Directory of Open Access Journals (Sweden)

    Frank Schaarschmidt

    2007-05-01

    Full Text Available A common statistical issue in seed-quality control is to prove that the proportion of individuals showing an unwanted trait is less than a small threshold. Group testing can be used to reduce costs of assay and upper confidence limits for the proportion of detrimental individuals can be used for either estimation or hypothesis testing. A crucial problem of group testing is the appropriate choice of group size in dependence of the number of groups, an assumed true proportion, and the threshold. This paper reports on experimental design to achieve high power for tests or low confidence interval width. Two agricultural applications are presented for which experimental design is discussed.

  15. Poly(esterimide) bearing azobenzene units as photoaligning layer for liquid crystals

    Science.gov (United States)

    Węgłowski, Rafał; Piecek, Wiktor; Kozanecka-Szmigiel, Anna; Konieczkowska, Jolanta; Schab-Balcerzak, Ewa

    2015-11-01

    The custom synthesized azobenzene side-chain poly(esterimide) was used as an aligning material for nematic liquid crystal molecules. The anisotropy of the poly(esterimide) layer was generated by a linearly polarized UV light, as a consequence of multiple trans-cis-trans isomerization cycles. The photoalignment effect was studied by assembling a twisted nematic cell with a proper liquid crystal mixture and geometry to fulfill Mauguin's limit. The polarizing microscope pictures of the fabricated cells confirmed the twisted arrangement of liquid crystal molecules. The results of electro-optic measurements indicated a stronger anchoring of the liquid crystal molecules by photoaligned poly(esterimide) than that obtained in the case of a rubbed polyimide.

  16. High diffraction efficiency polarization gratings recorded by biphotonic holography in an azobenzene liquid crystalline polyester

    International Nuclear Information System (INIS)

    High diffraction efficiencies have been achieved with polarization gratings recorded in thin films of an azobenzene side-chain liquid crystalline polyester by means of biphotonic processes. Efficiency values up to 30% have been reached after an induction period of 300 s and subsequent evolution with the sample in darkness. These values are at least two orders of magnitude higher than those previously reported for biphotonic recording. The gratings can be erased with unpolarized blue light and partial recovery of the diffraction efficiency has been observed after the erasure process when the sample is kept in darkness. Red light illumination of the erased film increases the recovered efficiency value and the recovery rate. [copyright] 2001 American Institute of Physics

  17. High diffraction efficiency polarization gratings recorded by biphotonic holography in an azobenzene liquid crystalline polyester

    DEFF Research Database (Denmark)

    Sánchez, C; Alcalá, R; Hvilsted, Søren;

    2001-01-01

    High diffraction efficiencies have been achieved with polarization gratings recorded in thin films of an azobenzene side-chain liquid crystalline polyester by means of biphotonic processes. Efficiency values up to 30% have been reached after an induction period of 300 s and subsequent evolution w...... is kept in darkness. Red light illumination of the erased film increases the recovered efficiency value and the recovery rate....... with the sample in darkness. These values are at least two orders of magnitude higher than those previously reported for biphotonic recording. The gratings can be erased with unpolarized blue light and partial recovery of the diffraction efficiency has been observed after the erasure process when the sample...

  18. A phylogenetic group of Escherichia coli associated with active left-sided inflammatory bowel disease

    DEFF Research Database (Denmark)

    Petersen, Andreas M; Nielsen, Eva M; Litrup, Eva;

    2009-01-01

    positive ExPEC gene among different groups, 86% were found positive among active IBD patients, significantly more than 13% among inactive IBD patients (p < 0.05), and 11% among healthy controls (p < 0.05). The B2 phylogenetic group was found in a specific cluster based on MLST, but no further separation......BACKGROUND: Escherichia coli have been found in increased numbers in tissues from patients with Inflammatory Bowel Disease (IBD) and adherent-invasive E. coli have been found in resected ileum from patients with Crohn's disease. This study aimed to characterize possible differences in phylogenetic...... 10 healthy controls. Disease activity was evaluated by sigmoidoscopy. Interestingly, E. coli strains of the phylogenetic group B2 were cultured from 60% of patients with IBD compared to 11% of healthy controls (p < 0.05). Furthermore, when comparing the number of E. coli B2 strains with at least one...

  19. SYNTHESIS OF NOVEL HYDROPHILIC BIODEGRADABLE POLYESTER WITH FUNCTIONALIZED SIDE CHAIN GROUPS

    Institute of Scientific and Technical Information of China (English)

    Ji-yuan Yang; Jian Yu; Huai-zhong Pan; Zhong-wei Gu; Wei-xiao Caoa; Xin-de Feng

    2001-01-01

    A substituted glycolide, 3-benzyloxymethyl-1,4-dioxane-2,5-dione, was synthesized. It is a suitable precursor for the preparation of a new hydrophilic biodegradable poly(a-hydroxy acid). The polymerizations were carried out in bulk in the presence of Sn(Oct)2 at 120-140℃. The resulting polymers were subjected to hydrogenolysis with a Pd/C catalyst in a mixed solvent to remove the protecting benzyl groups. A novel poly(a-hydroxy acid) with pendant hydroxy groups was obtained. The hydrophilicity of the resulting polymer was evaluated preliminarily.``

  20. D-Side: A Facility and Workforce Planning Group Multi-criteria Decision Support System for Johnson Space Center

    Science.gov (United States)

    Tavana, Madjid

    2005-01-01

    "To understand and protect our home planet, to explore the universe and search for life, and to inspire the next generation of explorers" is NASA's mission. The Systems Management Office at Johnson Space Center (JSC) is searching for methods to effectively manage the Center's resources to meet NASA's mission. D-Side is a group multi-criteria decision support system (GMDSS) developed to support facility decisions at JSC. D-Side uses a series of sequential and structured processes to plot facilities in a three-dimensional (3-D) graph on the basis of each facility alignment with NASA's mission and goals, the extent to which other facilities are dependent on the facility, and the dollar value of capital investments that have been postponed at the facility relative to the facility replacement value. A similarity factor rank orders facilities based on their Euclidean distance from Ideal and Nadir points. These similarity factors are then used to allocate capital improvement resources across facilities. We also present a parallel model that can be used to support decisions concerning allocation of human resources investments across workforce units. Finally, we present results from a pilot study where 12 experienced facility managers from NASA used D-Side and the organization's current approach to rank order and allocate funds for capital improvement across 20 facilities. Users evaluated D-Side favorably in terms of ease of use, the quality of the decision-making process, decision quality, and overall value-added. Their evaluations of D-Side were significantly more favorable than their evaluations of the current approach. Keywords: NASA, Multi-Criteria Decision Making, Decision Support System, AHP, Euclidean Distance, 3-D Modeling, Facility Planning, Workforce Planning.

  1. The bright and dark sides of individual and group innovation : a Special Issue introduction

    NARCIS (Netherlands)

    Janssen, O.; Van de Vliert, E.; West, M.A.

    2004-01-01

    This introduction essay proposes a challenging program for researchers eager to explore factors and process mechanisms contributing to the benefits and costs individuals and groups incur from pursuing innovative approaches. With respect to individual innovation, such moderating factors might be foun

  2. Geometry Control of Photo-induced Microstructures in an Azobenzene Polymer Film

    Institute of Scientific and Technical Information of China (English)

    Xu Ze-Da; LI Zhen; LIANG Li-Zhen; PENG Zhuo-Lun; CAI Zhi-Gang; ZHOU Jian-Ying; NINULESCU Valerica; ZHANG Ling-Zhi

    2001-01-01

    The mechanisms of photo-induced microstructures in an azobenzene polymer film are presented. They are based on the spatial periodic modulation of optical intensity and the photoisomerization of azobenzene molecules with the movement of main chains. Experiment and theory jointly point out the possibility of photo-inducing desired spatial microstructures in an azobenzene organic polymer via adequate optical lattices and adequately polarized ‘writing' beams.

  3. Polybenzimidazole Membranes Containing Benzimidazole Side Groups for High Temprature Polymer Electrolyte Membrane Fuel Cells

    DEFF Research Database (Denmark)

    Yang, Jingshuai; Li, Xueyuan; Xu, Yizin;

    2013-01-01

    Polybenzimidazole (PBI) with a high molecular weight of 69,000 was first synthesized. It was afterwards grafted with benzimidazole pendant groups on the backbones. The acid doped benzimidaozle grafted PBI membranes were investigated and characterized including fuel cell tests at elevated...... temperatures without humidification. At an acid doping level of 13.1 mol H3PO4 per average molar repeat unit, the PBI membranes with a benzimidazole grafting degree of 10.6% demonstrated a conductivity of 0.15 S cm-1 and a H2-air fuel cell peak power density of 378 mW cm-2 at 180 oC at ambient pressure without...

  4. Designed synthesis and chiroptical properties of regioregular poly(p-phenyleneethynylene-alter-m-phenyleneethynylene) bearing (-)-trans-rnyrtanoxyl side groups

    Institute of Scientific and Technical Information of China (English)

    Xiangfeng LI; Chusheng LI; Jiang LU; Hui LIANG

    2009-01-01

    Two regioregular poly(p-phenyleneethyny-lene-alter-m-phenyleneethynylene)s bearing (-)-trans-myrtanoxyl side groups with different substitution patterns were designed and synthesized, e.g. Myr-PMPE-1 and Myr-PMPE-2. In Myr-PMPE-1, the side chiral groups are distributed uniformly along the backbone. In Myr-PMPE-2, the distribution of the side chiral groups is alternatively crowded and loose. Both of these two polymers show no CD signal in solutions because of their good solubility. The investigations of chiroptical properties of these two polymers were carried out in the form of spin-coated films. The films were annealed above the glass temperature of the corresponding polymer, and the effects of annealing temperature and time on the properties of the films were investigated by UV-Vis absorption, fluorescence and circular dichroism spectra. The results show that annealing treatment had no significant effect on the properties of Myr-PMPE-1, including UV-Vis absorption, fluorescence and optical activity. The maximum absolute value of dissymmetry factor (|gmax|) was 1.62 × 10-4. On the other hand, annealing treatment significantly affected the proper-ties of Myr-PMPE-2. Without annealing or being annealed below 100℃, Myr-PMPE-2 films show almost no Cotton effect. In contrast, when annealed above 120℃, the absorption and emission of Myr-PMPE-2 films slightly red shifted with increasing annealing temperature and annealing time. Most importantly, the intensity of CD signals increased significantly and the optical activity of Myr-PMPE-2 films markedly increased. After annealing at 140℃ for 4h, the |gmax| of Myr-PMPE-2 films was increased up to 3.07 x 10 3, about one order of magnitude higher than that of Myr-PMPE-1 films.

  5. Sensing and transmission characteristics of a rocking filter fabricated in a side-hole fiber with zero group birefringence.

    Science.gov (United States)

    Anuszkiewicz, A; Martynkien, T; Mergo, P; Makara, M; Urbanczyk, W

    2013-05-20

    We report on sensing and transmission characteristics of rocking filters fabricated in a silica side-hole fiber with group birefringence changing its sign at certain wavelength (λ(G = 0)), which corresponds to parabolic-like spectral dependence of beat length. Unusual birefringence dispersion of the side-hole fiber is induced by an elliptical germanium doped core located in a narrow glass bridge between two holes. Rocking filters fabricated in such a fiber have two resonances of the same order located on both sides of λ(G = 0). The sensitivity of both resonances has an opposite sign, which makes it possible to double the response of the rocking filter by applying the differential interrogation scheme. We demonstrate that in this way a pressure sensitivity of the rocking filter can be enlarged to 132 nm/MPa. We also show that by fabricating the rocking filter with a period close to maximum beat length a coupling between polarization modes can be obtained in a broad band reaching 240 nm. PMID:23736486

  6. Electrochemical polymerization of an electron deficient fluorene derivative bearing ethylenedioxythiophene side groups

    Energy Technology Data Exchange (ETDEWEB)

    Bezgin, Buket [Department of Chemistry, Middle East Technical University, Inoenue Bulvari, 06531 Ankara (Turkey); Onal, Ahmet M., E-mail: aonal@metu.edu.t [Department of Chemistry, Middle East Technical University, Inoenue Bulvari, 06531 Ankara (Turkey)

    2010-01-01

    A new low band gap polyfluorene derivative, poly(2,7-bis-(2,3-dihydro-thieno[3,4-b][1,4]dioxin-5-yl)-fluoren-9-one) (PEFE), containing ethylenedioxythiophene as donor and fluorenone (FO) as an acceptor groups was electrochemically synthesized. Electrochemical polymerization of 2,7-bis-(2,3-dihydro-thieno[3,4-b][1,4]dioxin-5-yl)-fluoren-9-one (EFE) was achieved in dichloromethane with 0.1 M tetrabutylammonium-hexafluorophosphate both via and potentiostatic methods. The polymer was characterized by cyclic voltammetry, UV-vis, FT-IR and NMR spectroscopic techniques. Spectroelectrochemical and electrochemical analysis revealed that the polymer film is both p- and n-dopable and can be successfully cycled and switched between its neutral and oxidized/reduced states. Furthermore, PEFE shows electrochromic behavior by a color change from brown to blue with a switching time of 1.65 s during oxidation with a high coloration efficiency (250 cm{sup 2}/C). Fluorescence studies were also performed.

  7. Electrochemical polymerization of an electron deficient fluorene derivative bearing ethylenedioxythiophene side groups

    International Nuclear Information System (INIS)

    A new low band gap polyfluorene derivative, poly(2,7-bis-(2,3-dihydro-thieno[3,4-b][1,4]dioxin-5-yl)-fluoren-9-one) (PEFE), containing ethylenedioxythiophene as donor and fluorenone (FO) as an acceptor groups was electrochemically synthesized. Electrochemical polymerization of 2,7-bis-(2,3-dihydro-thieno[3,4-b][1,4]dioxin-5-yl)-fluoren-9-one (EFE) was achieved in dichloromethane with 0.1 M tetrabutylammonium-hexafluorophosphate both via and potentiostatic methods. The polymer was characterized by cyclic voltammetry, UV-vis, FT-IR and NMR spectroscopic techniques. Spectroelectrochemical and electrochemical analysis revealed that the polymer film is both p- and n-dopable and can be successfully cycled and switched between its neutral and oxidized/reduced states. Furthermore, PEFE shows electrochromic behavior by a color change from brown to blue with a switching time of 1.65 s during oxidation with a high coloration efficiency (250 cm2/C). Fluorescence studies were also performed.

  8. A remarkably efficient azobenzene peptide for holographic information storage

    DEFF Research Database (Denmark)

    Rasmussen, P.H.; Ramanujam, P.S.; Hvilsted, S.;

    1999-01-01

    A new family of proline-based azobenzene peptides (DNO) for holographic information storage is reported.:By use of polarization holography, it was found that gratings with extraordinarily high diffraction efficiency (up to 80%) can be recorded in hundreds of milliseconds in a similar to 13-mu m......-thick film of dimer 10. This represents a decrease of the response time by more than 2 orders of magnitude when compared to that of the ornithine-based DNO dimer previously reported. Furthermore, it supports the expectation that increasing the rigidity of the peptide backbone is: crucial in the design...... of effective azobenzene peptides for optical recording. Gratings recorded in 10 can be erased-by circularly polarized light in a few-seconds. It is also noted that, unlike DNOs previously reported, 10 is soluble in common organic solvents and can be assembled by solution phase synthesis, which is mandatory...

  9. Physical processes in azobenzene polymers on irradiation with polarized light

    DEFF Research Database (Denmark)

    Holme, N.C.R.; Nikolova, L.; Norris, T.B.;

    1999-01-01

    . A transition route based on experimental results for the theoretically calculated energy level scheme is proposed. Physical observations of surface relief in thin films of azobenzene polymers when irradiated with polarized light are reported. These include two beam polarization holographic observations...... and single beam transmission measurements through a mask, followed by atomic force microscope and profiler investigations. It is concluded that none of the prevalent theories can explain all the observed facts....

  10. Propagation of polarized light through azobenzene polyester films

    DEFF Research Database (Denmark)

    Nedelchev, L; Matharu, A; Nikolova, Ludmila;

    2002-01-01

    When elliptically polarized light of appropriate wavelength Corresponding to trans-cis-trans isomerisation process is incident on thin films of azobenzene polyesters, a helical structure is induced. We investigate the propagation of the exciting light beam (self-induced) as well as a probe light...... beam outside the absorption band through the polyester films. Investigations are carried out in one amorphous and one liquid crystalline polyester. We show that amorphous polyester after irradiation behaves like classical helical material....

  11. Rewritable azobenzene polyester for polarization holographic data storage

    DEFF Research Database (Denmark)

    Kerekes, A; Sajti, Sz.; Loerincz, Emoeke;

    2000-01-01

    gratings was studied in case of films with and without a hard protective layer. We showed that the dominant contribution to the diffraction efficiency comes from the anisotropy in case of expositions below 1 sec even for high incident intensity. The usage of the same wavelength for writing, reading...... and erasing was tested. The ability of azobenzene polyester for rewriting was found satisfactory after many writing-erasing cycles....

  12. Understanding the effect of side groups in ionic liquids on carbon-capture properties: a combined experimental and theoretical effort

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Fangyong [Univ. of California, Berkeley, CA (United States). Dept. of Chemical and Biomolecular Engingeering; Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Materials Sciences Division; Lartey, Michael [National Energy Technology Lab. (NETL), Pittsburgh, PA, (United States); Damodaran, Krishnan [National Energy Technology Lab. (NETL), Pittsburgh, PA, (United States); Univ. of Pittsburgh, PA (United States). Dept. of Chemistry; Albenze, Erik [National Energy Technology Lab. (NETL), Pittsburgh, PA, (United States); URS Corporation, South Park, PA (United States); Thompson, Robert L. [National Energy Technology Lab. (NETL), Pittsburgh, PA, (United States); URS Corporation, South Park, PA (United States); Kim, Jihan [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Materials Science Div.; Harancyzk, Maciel [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Computational Research Div.; Nulwala, Hunaid B. [National Energy Technology Lab. (NETL), Pittsburgh, PA, (United States); Carnegie Mellon Univ., Pittsburgh, PA (United States); Luebke, David R. [National Energy Technology Lab. (NETL), Pittsburgh, PA, (United States); Smit, Berend [Univ. of California, Berkeley, CA (United States). Dept. of Chemical and Biomolecular Engingeering; Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Materials Sciences Division

    2013-01-01

    Ionic liquids are an emerging class of materials with applications in a variety of fields. Steady progress has been made in the creation of ionic liquids tailored to specific applications. However, the understanding of the underlying structure–property relationships has been slower to develop. As a step in the effort to alleviate this deficiency, the influence of side groups on ionic liquid properties has been studied through an integrated approach utilizing synthesis, experimental determination of properties, and simulation techniques. To achieve this goal, a classical force field in the framework of OPLS/Amber force fields has been developed to predict ionic liquid properties accurately. Cu(I)-catalyzed click chemistry was employed to synthesize triazolium-based ionic liquids with diverse side groups. Values of densities were predicted within 3% of experimental values, whereas self-diffusion coefficients were underestimated by about an order of magnitude though the trends were in excellent agreement, the activation energy calculated in simulation correlates well with experimental values. The predicted Henry coefficient for CO{sub 2} solubility reproduced the experimentally observed trends. This study highlights the importance of integrating experimental and computational approaches in property prediction and materials development, which is not only useful in the development of ionic liquids for CO{sub 2} capture but has application in many technological fields.

  13. Light intensity dependent optical rotation in azobenzene polymers

    Science.gov (United States)

    Ivanov, M.; Ilieva, D.; Petrova, T.; Dragostinova, V.; Todorov, T.; Nikolova, L.

    2006-05-01

    We investigate the self-induced rotation of the azimuth of light polarization ellipse in azobenzene polymers. It is initiated by the photoreorientation and ordering of the azobenzenes on illumination with elliptically polarized light resulting in the appearance of an optical axis whose direction is gradually rotated along the depth of the film. A macroscopic chiral structure is created with a pitch depending on light ellipticity and the photobirefringence ▵n in the successive layers of the film. In this work we make use of the fact that at elevated temperatures ▵n is very sensitive to light intensity. In our acrylic amorphous azobenzene polymer at temperatures 50-65°C the saturated values of ▵n are much higher for low intensity of the exciting light than for higher intensity. In this temperature range the polarization azimuth of monochromatic blue light with different intensity is rotated to a different angle after passing through the polymer film. This effect can be used for passive elements rotating the polarization azimuth depending on light intensity and for the formation of light beams with a space-variant polarization state.

  14. Dicyclopalladated complexes of asymmetrically substituted azobenzenes: synthesis, kinetics and mechanisms.

    Science.gov (United States)

    Juribašić, Marina; Budimir, Ana; Kazazić, Snježana; Curić, Manda

    2013-11-01

    Two series of new dicyclopalladated complexes {(DMF)PdCl(μ-R(1)C6H3N═NC6H3R(2))PdCl(DMF)} of 4,4'-functionalized azobenzenes with substituents of varying electron-donating or electron-withdrawing strength (R(1) = H, NMe2; R(2) = H, Cl, Br, I, OMe, PhNH, CO2H, SO3Na, or NO2) have been synthesized and fully characterized. (1)H NMR spectroscopy along with the ESI mass spectrometry unambiguously identified the new complexes in the solution, and their solid-state structures were determined by X-ray crystallography. The presence of easily exchangeable solvent ligands was confirmed by (1)H NMR spectroscopy, X-ray experiments, and ESI mass spectrometry. The complexes were additionally characterized by UV-vis and fluorescence spectroscopies. The effect of different 4,4'-substituents on the formation rate of mono- and dicyclopalladated azobenzenes was studied by UV-vis spectroscopy. The experimental results are complemented by the quantum-chemical (DFT) calculations in order to rationalize the kinetic results as well as substituent effects on the reaction rates. It was found that the mono- and dicyclopalladation reactions of azobenzenes proceed in two consecutive processes, adduct formation and palladation steps. The rate-determining step in both palladations is the breaking of the ortho C-H bond, which has been confirmed as an electrophilic substitution process by Hammett correlations and DFT calculations. PMID:24116960

  15. A dynamic and ultrafast group delay tuning mechanism in two microcavities side-coupled with a waveguide system

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Boyun; Wang, Tao, E-mail: wangtao@hust.edu.cn; Tang, Jian; Li, Xiaoming; Zhu, Youjiang [Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430074 (China)

    2014-10-07

    We theoretically propose a dynamic and ultrafast group delay tuning mechanism in two microcavities side-coupled to a waveguide system through external optical pump beams. The optical Kerr effect modulation method is applied to improve tuning rate with response time of subpicoseconds or even femtoseconds. The group delay of an all-optical analog to electromagnetically induced transparency effect can be controlled by tuning either the frequency of photonic crystal microcavities or the propagation phase of line waveguide. Group delay is controlled between 5.88 and 70.98 ps by dynamically tuning resonant frequencies of the microcavities. Alternatively, the group delay is controlled between 1.86 and 12.08 ps by dynamically tuning the propagation phase of line waveguide. All observed schemes are analyzed rigorously through finite-difference time-domain simulations and coupled-mode formalism. Results show a new direction toward microstructure integration optical pulse trapping and all-optical dynamical storage of light devices in optical communication and quantum information processing.

  16. Kinetic analysis of the thermal isomerisation pathways in an asymmetric double azobenzene switch

    NARCIS (Netherlands)

    Robertus, Jort; Reker, Siebren F.; Pijper, Thomas C.; Deuzeman, Albert; Browne, Wesley R.; Feringa, Ben L.

    2012-01-01

    Here we report a photochemical and kinetic study of the thermal relaxation reaction of a double azobenzene system, in which two azobenzene photochromic units are connected via a phenyl ring. Upon UV irradiation, three thermally unstable isomers are formed. Kinetic studies using arrayed H-1-NMR spect

  17. Quantum theory and experimental studies of absorption spectra and photoisomerization of azobenzene polymers

    DEFF Research Database (Denmark)

    Pedersen, Thomas Garm; Ramanujam, P.S.; Johansen, P.M.;

    1998-01-01

    The microscopic properties of azobenzene chromophores are important for a correct description of optical storage systems based on photoinduced anisotropy in azobenzene polymers. A quantum model of these properties is presented and verified by comparison to experimental absorption spectra for tran...

  18. Protonated Dipeptide Losses from b 5 and b 4 Ions of Side Chain Hydroxyl Group Containing Pentapeptides

    Science.gov (United States)

    Atik, A. Emin; Yalcin, Talat

    2013-10-01

    In this study, C-terminal protonated dipeptide eliminations were reported for both b 5 and b 4 ions of side chain hydroxyl group (-OH) containing pentapeptides. The study utilized the model C-terminal amidated pentapeptides having sequences of XGGFL and AXVYI, where X represents serine (S), threonine (T), glutamic acid (E), aspartic acid (D), or tyrosine (Y) residue. Upon low-energy collision-induced dissociation (CID) of XGGFL (where X = S, T, E, D, and Y) model peptide series, the ions at m/z 279 and 223 were observed as common fragments in all b 5 and b 4 ion (except b 4 ion of YGGFL) mass spectra, respectively. By contrast, peptides, namely SMeGGFL-NH2 and EOMeGGFL-NH2, did not show either the ion at m/z 279 or the ion at m/z 223. It is shown that the side chain hydroxyl group is required for the possible mechanism to take place that furnishes the protonated dipeptide loss from b 5 and b 4 ions. In addition, the ions at m/z 295 and 281 were detected as common fragments in all b 5 and b 4 ion (except b 4 ion of AYVYI) mass spectra, respectively, for AXVYI model peptide series. The MS4 experiments exhibited that the fragment ions at m/z 279, 223, 295, and 281 entirely reflect the same fragmentation behavior of [M + H]+ ion generated from commercial dipeptides FL-OH, GF-OH, YI-OH, and VY-OH. These novel eliminations reported here for b 5 and b 4 ions can be useful in assigning the correct and reliable peptide sequences for high-throughput proteomic studies.

  19. Base-Catalyzed Hydrophosphination of Azobenzenes with Diarylphosphine Oxides: A Precise Construction of N-N-P Unit.

    Science.gov (United States)

    Hong, Gang; Zhu, Xiaoyan; Hu, Chen; Aruma, Alfred Njasotapher; Wu, Shengying; Wang, Limin

    2016-08-01

    Addition of diarylphosphine oxides to the N═N double bond of azobenzenes leads to the formation of the P-substituted hydrazines in up to 98% yield for 24 examples, and the formation of diphenylphosphinic amides was observed in three substrates. This strategy features tolerance of a wide range of functional groups, simple operation, and mild reaction conditions. Specially, this method can be also applied to the gram-scale synthesis of the product. A polar reaction mechanism is also proposed based on control experiments. PMID:27387595

  20. Tuning the Photoinduced Motion of Glassy Azobenzene Polymers and Networks

    Science.gov (United States)

    Vaia, R. A.

    2013-03-01

    Continual innovation at the forefront of soft-matter, in areas such as liquid crystal networks, nano-composites and bio-molecules, is providing exciting opportunities to create smart materials systems that exhibit a controlled, reproducible and reversible modulation of physical properties. These material systems evoke the adaptivity of natural organisms, and inspire radical aerospace notions. A key example is photo-responsive polymers, which convert a light stimulus input into a mechanical output (work). Photoinduced conformational changes, such as within azobenzene, dictate molecular-level distortions that summate into a macroscopic strain, which often manifests as a shape change or motion. The transduction of the molecular-level response to a macroscale effect is regulated by mesoscopic features, such as chain packing, free volume, and local molecular order - factors which depend on chemical composition as well as the process history of the material. For example, physical aging increases the density of the glass, reduces local free volume, and thus decreases the minima in local conformation space which strongly influences the azobenzene photochemistry (trans-cis-trans isomerization). The subsequent change in the energy landscape of the system reduces the fraction of azobenzene able to undergo reconfiguration as well as increases the probability that those photoinduced conformations will relax back to the initial local environment. The result is a tuning of the magnitude of macroscopic strain and the ability to shift from shape fixing to shape recovery, respectively. Work done in collaboration with H. Koerner, K.M. Lee, M. Smith, D. Wang, L-S. Tan. and T. White, Air Force Research Laboratory.

  1. Photoresponsive Block Copolymers Containing Azobenzenes and Other Chromophores

    Directory of Open Access Journals (Sweden)

    Takaomi Kobayashi

    2010-01-01

    Full Text Available Photoresponsive block copolymers (PRBCs containing azobenzenes and other chromophores can be easily prepared by controlled polymerization. Their photoresponsive behaviors are generally based on photoisomerization, photocrosslinking, photoalignment and photoinduced cooperative motions. When the photoactive block forms mesogenic phases upon microphase separation of PRBCs, supramolecular cooperative motion in liquid-crystalline PRBCs enables them to self-organize into hierarchical structures with photoresponsive features. This offers novel opportunities to photocontrol microphase-separated nanostructures of well-defined PRBCs and extends their diverse applications in holograms, nanotemplates, photodeformed devices and microporous films.

  2. Correlation between the molecular structure and trans←→ cis isomerization characteristics of azobenzenes

    Institute of Scientific and Technical Information of China (English)

    HAN Mina; HONDA Takumu

    2012-01-01

    Photochemical and thermal isomerization of various azobenzenes was systematically investigated to understand the correlation between the molecular structure and trans←→cis isomerization characteristics of azobenzenes.A blue shift in π-π* absorption band of ortho-alkylated azobenzenes (1o and 2o) was observed together with a reduction in molar extinction coefficient (ε) in comparison with both meta-alkylated azobenzenes (4m and 5m) and 7p lacking the meta and ortho substituents.For ortho-alkylated azobenzene,photochemical trans-to-cis isomerization and thermal back cis-to-trans isomerization in solution occurred slowly when compared with 4m,5m and 7p.The half-life time of the cis form of 2o was found to be 380 h,which is about 8-50 times longer than those of comparable 4m,5m (43-13 h) and 7p (7h).Furthermore,comparison of the molecular structure and isomerization characteristics of azobenzene thiol (2oand 5m) self-assembled monolayers on flat gold surfaces indicates that the trans-to-cis photoconversion in monolayer systems is influenced by steric hindrance and strong intermolecular interaction between azobenzene units.

  3. Analysis of the Contribution of Chromophores in Side Groups of Amino Acids to the Absorption Spectrum of Hemoglobin

    Science.gov (United States)

    Lavrinenko, I. A.; Vashanov, G. A.; Ruban, M. K.

    2014-01-01

    Based on spectral analysis of solutions of aromatic, heterocyclic, and sulfur-containing amino acids, we propose an additive model and assess the roles of the studied types of amino acid residues in formation of the overall absorption spectrum of hemoglobin. We have established that the identified absorption maxima (transitions) at 243.4, 248.4, 253.2, 258.8, 261.6, 264.8, and 268.4 nm belong to phenylalanine amino acid residues. Probably the latter also form the unassigned transition at 241.0 nm. The transitions at 272.8, 274.6, 280.0, and 284.4 nm are a superposition of the absorption by the side groups of tyrosine and tryptophan; the transition at 278.2 nm is associated with tyrosine, masked by adjacent transitions of tryptophan, and the transition at 291.2 nm belongs to tryptophan. We consider the possibility of estimating the changes in the spectral properties of proteins under the influence of various physical and chemical factors using data from additive spectra.

  4. An Optimized Glutamate Receptor Photoswitch with Sensitized Azobenzene Isomerization.

    Science.gov (United States)

    Gascón-Moya, Marta; Pejoan, Arnau; Izquierdo-Serra, Mercè; Pittolo, Silvia; Cabré, Gisela; Hernando, Jordi; Alibés, Ramon; Gorostiza, Pau; Busqué, Félix

    2015-10-16

    A new azobenzene-based photoswitch, 2, has been designed to enable optical control of ionotropic glutamate receptors in neurons via sensitized two-photon excitation with NIR light. In order to develop an efficient and versatile synthetic route for this molecule, a modular strategy is described which relies on the use of a new linear fully protected glutamate derivative stable in basic media. The resulting compound undergoes one-photon trans-cis photoisomerization via two different mechanisms: direct excitation of its azoaromatic unit and irradiation of the pyrene sensitizer, a well-known two-photon sensitive chromophore. Moreover, 2 presents large thermal stability of its cis isomer, in contrast to other two-photon responsive switches relying on the intrinsic nonlinear optical properties of push-pull substituted azobenzenes. As a result, the molecular system developed herein is a very promising candidate for evoking large photoinduced biological responses during the multiphoton operation of neuronal glutamate receptors with NIR light, which require accumulation of the protein-bound cis state of the switch upon repeated illumination.

  5. Conformational Dynamics of o-Fluoro-Substituted Z-Azobenzene.

    Science.gov (United States)

    Rastogi, S K; Rogers, R A; Shi, J; Gao, C; Rinaldi, P L; Brittain, W J

    2015-11-20

    A conformational analysis of o-fluoro Z-azobenzene reveals a slight preference for aromatic C-F/π interaction. Density functional theory (DFT) indicates that the conformation with a C-F/π interaction is preferred by approximately 0.3-0.5 kcal/mol. Ground-state conformations were corroborated with X-ray crystallography. (Z)-Azobenzene (Z-AB) with at least one o-fluoro per ring displays (19)F-(19)F through-space (TS) coupling. 2D J-resolved NMR was used to distinguish through-bond from TS coupling ((TS)JFF). (TS)JFF decreases as the temperature is lowered and the multiplets coalesce into broad singlets. We hypothesize that the coalescence temperature (Tc) corresponds to the barrier for phenyl rotation. The experimentally determined barrier of 8-10 kcal/mol has been qualitatively verified by DFT where transition states with a bisected geometry were identified with zero-point energies of 6-9 kcal/mol relative to ground state. These values are significantly higher that values estimated from previous theoretical studies but lie within a reasonable range for phenyl rotation in hydrocarbon systems.

  6. Light-induced circular birefringence in cyanoazobenzene side-chain liquid-crystalline polyester films

    DEFF Research Database (Denmark)

    Naydenova, I; Nikolova, L; Ramanujam, P.S.;

    1999-01-01

    degrees mu m(-1) at 633 nm and three to four times larger at 488 nm. The effect is explained through photoinduced changes in the structure of the polymer films due to reorientation of the rod-like chromophores and angular momentum transfer from the circularly polarized light to the azobenzene side chains....

  7. Symmetrical trimeric star-shaped mesogens based on 1,3,5-trisubstituted benzene incorporating Schiff base and azobenzene fragments as the peripheral units: Synthesis and mesomorphic properties

    Indian Academy of Sciences (India)

    Guan-Yeow Yeap; Yew-Hong Ooi; Nozomi Uchida; Masato M Ito

    2014-05-01

    Two series of symmetrical three-armed star-shaped mesogens based on 1,3,5-trihydroxybenzene as a core unit, interconnecting three Schiff base or azobenzene moieties via oxymethylene spacers have been synthesized and characterized by spectroscopic techniques. Every member in these series possesses either chlorine (Cl) or bromine (Br) terminal atom, with different alkyl spacer length (CH2 whereby ranging from 3 to 6). Their thermal stability and mesomorphic properties are investigated by employing DSC and POM. The dependence of phase transition in relation to the alkyl spacer length is shown by both series. These star-shaped mesogens exhibit only nematic and smectic phases. The difference between the two series lies on the structure of linking group in the peripheral units (-CH=N- for series PSB-X- and -N=N- for series PAZ-X-). Therefore, a comparison study of the mesomorphic properties between these two series of star-shaped mesogens is discussed whereby the azobenzene-basedmesogens are thermally more stable than the Schiff base counterpart. In addition, soft crystalline phase is observed for the azobenzene-based star-shaped mesogens possessing hexyl alkyl spacer.

  8. Optical Modulation of the Diffraction Efficiency in an Indoline Azobenzene/Amorphous Polycarbonate Film.

    Science.gov (United States)

    Williams, G V M; Do, My T T; Middleton, A; Raymond, S G; Bhuiyan, M D H; Kay, A J

    2016-12-01

    We have made a diffraction grating in an indoline azobenzene/amorphous polycarbonate film by two-beam interference at 532 nm that periodically photodegrades the indoline azobenzene dye. Subsequent illumination of the film with 532-nm light into the trans-isomer band leads to trans-cis isomerization in the indoline azobenzene dye and results in a decrease in the trans-isomer band absorption coefficient. This causes the diffraction efficiency to decrease when probed at 655 nm. The diffraction efficiency returns to its original value when the 532-nm light is blocked by thermal relaxation from the indoline azobenzene cis-isomer to the trans-isomer. Thus, we have been able to optically modulate the diffraction efficiency in a thin film diffraction grating. PMID:27416904

  9. Theoretical Investigation of Nonlinear Optical Properties of Organic and Transition Metal Hybrid Azobenzene Dendrimers

    Institute of Scientific and Technical Information of China (English)

    LIU Cai-Ping; LIU Ping; WU Ke-Chen

    2008-01-01

    In this work, we report a theoretical exploration of the responses of organic azo-benzene dendrimers. The polarizabilities, the first and second hyperpolarizabilities of the azobenzene monomers (GO), and the first, second and third generation (G1, G2 and G3, respectively) are investigated by semi-empirical methods. The calculated results show that the nonlinear optical (NLO)properties of these organic dendrimers are mainly determined by the azobenzene chromospheres.Additionally, the values of β and γ increase almost in proportion to the number of chromophores. On the other hand, two types of transition metal hybrid azobenzene dendrimers (core-hybrid and branch-end hybrid according to the sites combined with transition metals) are simulated and discussed in detail in the framework of time-dependent density functional theory (TDDFT). The calculated results reveal that the NLO responses of these metal dendrimers distinctly varied as a result of altering the charge transfer transition scale and the excitation energies.

  10. POLYMER SCAFFOLDS BEARING AZOBENZENE —— POTENTIAL FOR OPTICAL INFORMATION STORAGE

    Institute of Scientific and Technical Information of China (English)

    Sφren Hvilsted; P.S. Ramanujam

    2001-01-01

    The fundamental optical storage mechanism of the laser light addressable azobenzene moiety is briefly introduced.A modular and flexible synthesis design furnishes polyester matrices covalently integrating cyanoazobenzene in regularly spaced side chains. Thin films of these materials are particularly well suited for holographic storage. Notable figures of merits of liquid crystalline polyesters are response time to blue-green laser light of the order of nanoseconds, storage capacity expressed as 5000 lines/mm, and high, permanent (almost nine years) diffraction efficiency of the order of 50% or greater,and erasability. The implications of the main chain nature for polyester morphology and for the permanency of the induced anisotropy are discussed. The design and methods of preparation of other significantly different polymer scaffolds supporting cyanoazobenzene are elaborated. Oligopeptides always result in amorphous materials, whereas copolymethacrylates and dendritic or hyperbranched polyesters provide some materials that exhibit liquid crystallinity. However, none of these scaffolds affords materials that result in permanent anisotropy when exposed to interfering laser light.

  11. Cis-trans isomerisation of azobenzenes studied by NMR spectroscopy with in situ laser irradiation and DFT calculations

    OpenAIRE

    Wazzan, Nuha

    2009-01-01

    NMR spectroscopy with in situ laser irradiation has been used to investigate the photo- and thermal isomerisation of eight azobenzene derivatives; diphenyldiazene (azobenzene), p-phenylazoaniline (p-aminoazobenzene), 4-(dimethylamino)azobenzene (Methyl Yellow), 4-dimethylamino-2-methylazobenzene (o-Methyl-Methyl Yellow), p-nitroazobenzene, 4-nitro-4’-dimethylaminoazobeneze (Dimethyl-nitroazobenzene), 4-(4-nitrophenylazo)aniline (Disperse Orange 3) and N-ethyl-N-(2-hydroxyethyl)-4-(4-nitrophen...

  12. Antimicrobial azobenzene compounds and their potential use in biomaterials

    Science.gov (United States)

    Sessa, L.; Concilio, S.; Iannelli, P.; De Santis, F.; Porta, A.; Piotto, S.

    2016-04-01

    We recently synthesized a class of active compounds with azobenzene structure [1] and lowest in silico toxicity values. The antimicrobial activity of these molecules and their thermal stability are very promising and indicate that they may have interesting and therapeutically significant applications. This work aims to develop new materials with antibacterial and antifungal activity inserting different percentages of synthetic antimicrobial azo compounds in commercial polymer matrices. We realized thin films using solvent casting and melt compounding techniques. The obtained materials retained the proprieties of the pure matrices. This means that azo dye dissolved in the matrix does not influence the thermal behavior and the morphology of the material. Tested films exhibited the capability to inhibit biofilms formation of S. aureus and C. albicans. Spectrophotometric investigation of the azo compound released from the polymer matrices confirmed that the realized materials might be interesting for biomedical tools, antibacterial surfaces, and films for active packaging.

  13. A Helical Polyphenylacetylene Having Amino Alcohol Moieties Without Chiral Side Groups as a Chiral Ligand for the Asymmetric Addition of Diethylzinc to Benzaldehyde.

    Science.gov (United States)

    Liu, Lijia; Long, Qing; Aoki, Toshiki; Zhang, Geng; Kaneko, Takashi; Teraguchi, Masahiro; Zhang, Chunhong; Wang, Yudan

    2015-08-01

    One-handed helical polyphenylacetylenes having achiral amino alcohol moieties, but no chiral side groups, were synthesized by the helix-sense-selective copolymerization of an achiral phenylacetylene having an amino alcohol side group with a phenylacetylene having two hydroxyl groups. Since the resulting helical copolymers were successfully utilized as chiral ligands for the enantioselective alkylation of benzaldehyde with diethylzinc, we can conclude that the main-chain chirality based on the one-handed helical conformation is useful for the chiral catalysis of an asymmetric reaction for the first time. The enantioselectivities of the reaction were controlled by the optical purities of the helical polymer ligands. In addition, the polymer ligands could be easily recovered by precipitation after the reaction.

  14. Polarization holographic gratings in side-chain azobenzene polyesters with linear and circular photoanisotropy

    DEFF Research Database (Denmark)

    Nikolova, Ludmila; Todorov, T.; Ivanov, Mario Tonev;

    1996-01-01

    We investigate thin phase polarization holographic gratings recorded with two waves with orthogonal linear polarizations in materials in which illumination with linearly/circularly polarized light gives rise to linear/circular birefringence. The theoretical analysis shows that the presence of cir...

  15. Self-assembly of azobenzene based side-chain liquid crystalline polymer and -alkyloxybenzoic acids

    Indian Academy of Sciences (India)

    Kumarasamy Gayathri; Subramanian Balamurugan; Palaninathan Kannan

    2011-05-01

    Liquid crystalline pendant polymeric complexes have been obtained by supramolecular assembly of two mesogenic components namely, poly[4-(10-acryloyloxydecyloxy)-4'- phenylazobenzonitrile] (P10) and 4-alkyloxybenzoic acids (A7-A12). Hydrogen bond formed between carboxylic acid and cyano moiety served as molecular bridge. The polymeric complexes acquitted as undivided liquid crystalline properties exhibited stable and enantiotropic mesophases. The precursor, monomer and polymer were analysed by 1H-NMR and 13C-NMR spectroscopy. The hydrogen bonding interaction in polymer complexes (P10-A7 to P10-A12) was investigated by FT-IR spectroscopy. The thermal behaviours and textural analysis were studied by differential scanning calorimetry and polarized optical microscopy respectively.

  16. Splitting failure in side walls of a large-scale underground cavern group: a numerical modelling and a field study.

    Science.gov (United States)

    Wang, Zhishen; Li, Yong; Zhu, Weishen; Xue, Yiguo; Yu, Song

    2016-01-01

    Vertical splitting cracks often appear in side walls of large-scale underground caverns during excavations owing to the brittle characteristics of surrounding rock mass, especially under the conditions of high in situ stress and great overburden depth. This phenomenon greatly affects the integral safety and stability of the underground caverns. In this paper, a transverse isotropic constitutive model and a splitting failure criterion are simultaneously proposed and secondly programmed in FLAC3D to numerically simulate the integral stability of the underground caverns during excavations in Dagangshan hydropower station in Sichuan province, China. Meanwhile, an in situ monitoring study on the displacement of the key points of the underground caverns has also been carried out, and the monitoring results are compared with the numerical results. From the comparative analysis, it can be concluded that the depths of splitting relaxation area obtained by numerical simulation are almost consistent with the actual in situ monitoring values, as well as the trend of the displacement curves, which shows that the transverse isotropic constitutive model combining with the splitting failure criterion is appropriate for investigating the splitting failure in side walls of large-scale underground caverns and it will be a helpful guidance of predicting the depths of splitting relaxation area in surrounding rock mass. PMID:27652101

  17. Quantitative Structure-activity Relationships for Anaerobic Biodegradation of Substituted Azobenzenes

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xiao-yi; ZHU Huai-wu; LUO Shi-xia; WANG Zheng-wu; XIAO Han

    2004-01-01

    The degradation rates of the azo-bonds of a series of substituted azobenzenes caused by anaerobic sludge digestion were determined by measuring the biggest change of the absorption peak area of the UV-Vis spectra of the anaerobic sludge system before and after degradation. The electronic structure of the molecules was calculated by using the quantum chemistry semiempirical method AM1. The research on the correlation between the biodegradability of the azo-bond and the molecular structure descriptors has led to the following results. (1) There is an obvious relationship between the degradation rate D and the difference Δqπ in π-charge density of the azo-bond. (2) The different substituents in the molecules result in a wave pattern of π-charge distribution and the increasing of the flowability of π-electron. A good flowability of the π-charge favors the reduction between electron contributing azo groups. (3) The effect of the substituents on the π-electron system depends on the electromerization of the substituents in combination with the conjugated systems.

  18. Photoinduced formation of an azobenzene-based CD-active supramolecular cyclic dimer.

    Science.gov (United States)

    Sogawa, Hiromitsu; Terada, Kayo; Miyagi, Yu; Shiotsuki, Masashi; Inai, Yoshihito; Masuda, Toshio; Sanda, Fumio

    2015-04-27

    A series of new photo-responsive amino acid-derived azobenzenedicarboxylic acid derivatives (S)-1 a-e were synthesized. Compound (S)-1 a in the trans form exhibited no circular dichroism (CD) signal in DMF under ambient conditions, whereas intense Cotton effects were observed upon UV irradiation, indicating the formation of a chiral supramolecular structure in the cis form. The CD signals disappeared when trifluoroacetic acid (TFA) was added to the solution. The ester counterpart [(S)-1 a'] showed no CD signal. Hydrogen bonding between the carboxy groups seemed necessary for constructing the supramolecular structure. The kinetic studies of cis to trans isomerization of (S)-1 a demonstrated that the formation of a chiral supramolecule enhances the stability of the cis-azobenzene structure. The ESI mass spectrum of stilbenedicarboxylic acid (S)-4, an analogue of (S)-1 b, confirmed the formation of a dimer. A theoretical CD study revealed that (S)-1 a in the cis form should be present as a cyclic chiral dimer.

  19. Optically switchable multi-stopband of non-quarter-wavelength dielectric multilayer using azobenzene polymer liquid crystal

    Science.gov (United States)

    Ozaki, Ryotaro; Kadowaki, Kazunori; Hagio, Takashi; Yagi, Ryohei; Kuwahara, Yutaka; Kurihara, Seiji

    2015-09-01

    Non-quarter-wave stacked dielectric multilayers including azobenzene polymer liquid crystal layers are investigated in this study. The azobenzene polymer liquid crystal has a photoinduced reversible refractive index based on photoisomerization. By using the reversible refractive-index change, the reflectance of a stopband can be controlled. In this system, the azobenzene molecules change their conformation when they are irradiated with ultraviolet (UV) or visible light. In general, stacking many layers of different thicknesses can produce broadband or multicolor reflections for a dielectric multilayer. However, in a multilayer having thick azobenzene layers, UV or visible light used for controlling photoisomerization hardly reaches the bottom part of the multilayer because the light is mainly absorbed at its top surface. To solve this problem, the dependence on the thickness ratio of the multilayer is investigated and a non-quarter-wave stacked multilayer having RGB reflections is experimentally demonstrated using thin azobenzene layers.

  20. Insights into genetic diversity, parentage, and group composition of Atlantic white-sided dolphins (Lagenorhynchus acutus) off the west of Ireland based on nuclear and mitochondrial genetic markers.

    Science.gov (United States)

    Mirimin, Luca; Banguera-Hinestroza, Eulalia; Dillane, Eileen; Hoelzel, Alan R; Cross, Tom F; Rogan, Emer

    2011-01-01

    The analysis of stranding events and the application of molecular markers can be powerful tools to study cryptic biological aspects of delphinid species that occur mainly in open ocean habitat. In the present study, we investigated nuclear and mitochondrial genetic variability of Atlantic white-sided dolphins that stranded from 1990 to 2006 (n = 42) along the west coast of Ireland, using 8 microsatellite loci and 599 bp of the mitochondrial DNA control region. Results from both classes of markers are concordant with the hypothesis of a large random-mating population of white-sided dolphins along the west coast of Ireland. In addition, the analyses of 2 live mass stranding events (19 and 5 individuals, respectively) revealed that dolphins within each group were mainly unrelated to each other, suggesting dispersal of both sexes from the natal group (i.e., no natal phylopatry). Parentage analyses allowed the identification of mother-offspring pairs but ruled out all adult males as possible fathers. In combination with data on age of individuals, these results confirmed previous knowledge on life-history parameters, with sexually mature females ranging between 11 and 15 years of age and an interbirth interval of at least 2 years. The present study provides novel information on population and group composition of Atlantic white-sided dolphins along the west coast of Ireland, where population and social structure of the species are still poorly understood. PMID:21059883

  1. Detection of NO2 Based on 4-Carboxyl-4'-hydroxy Azobenzene and Its Cu(Ⅱ) Complex

    Institute of Scientific and Technical Information of China (English)

    LI Jian; GONG Yun; QIN Jian-Bo; LIN Jian-Hua

    2013-01-01

    An organic ligand and its Cu(Ⅱ) complex formulated as (C13H10N2O3)·5H2O (H2L·5H2O,1) and Cu(HL)2(phen)·0.125H2O (2,H2L =4-carboxyl-4'-hydroxy azobenzene,phen =1,10-phenanthroline) have been synthesized and structurally characterized by single-crystal X-ray diffraction.In the two compounds,H2L and HL exhibit a trans-conformation.Complex 2 shows a mononuclear Cu(Ⅱ) structure with the hydroxyl group of HL uncoordinated.Complex 2 is assembled into a three-dimensional (3D) supramolecular architecture by hydrogen bonds and π-π stacking interactions,H2L and compound 2 can detect NO2 via reversible and irreversible color changes,respectively.The mechanism for the color changes is investigated.

  2. Reflection Band Control of Inverse Opal Film with Photoresponse Properties of Push-Pull Type Azobenzene LC Polymers

    Directory of Open Access Journals (Sweden)

    Takahiro Shiozawa

    2008-07-01

    Full Text Available DcAz2Mc and DR1Mc molecules having push-pull type of azobenzene groups are synthesized, and their photo-orientational behaviors are investigated in the polymer system. In order to understand the relationship between a molecular structure and its physical properties, electronic structure calculation is computationally carried out. Regarding to their photo response properties, the copolymers of poly(DcAz2Mc-co-M6PBMe and poly(DR1Mc-co-M6PBMe are infiltrated into inverse opal films, and Bragg reflection shifts are observed under photostimuli. When the linearly polarized light is irradiated, Bragg reflection bands are shifted to the longer wavelength region as reflective index increases.

  3. Probing the effects of the ester functional group, alkyl side chain length and anions on the bulk nanostructure of ionic liquids: a computational study.

    Science.gov (United States)

    Fakhraee, Mostafa; Gholami, Mohammad Reza

    2016-04-14

    The effects of ester addition on nanostructural properties of biodegradable ILs composed of 1-alkoxycarbonyl-3-alkyl-imidazolium cations ([C1COOCnC1im](+), n = 1, 2, 4) combined with [Br](-), [NO3](-), [BF4](-), [PF6](-), [TfO](-), and [Tf2N](-) were explored by using the molecular dynamics (MD) simulations and quantum theory of atoms in molecules (QTAIM) analysis at 400 K. Various thermodynamic properties of these ILs were extensively computed in our earlier work (Ind. Eng. Chem. Res., 2015, 54, 11678-11700). Nano-scale segregation analysis demonstrates the formation of a small spherical island-like hydrocarbon within the continuous ionic domain for ILs with short alkyl side chain ([C1COOC1C1im]), and a sponge-like nanostructure for the compound with long alkyl side chain ([C1COOC4C1im]). Ester-functionalized ILs with ethyl side chain ([C1COOC2C1im]) are the turning point between two different morphologies. Non-polar channels were observed for [C1COOC4C1im] ILs composed of smaller anions such as [Br] and [NO3], whereas clustering organization was found for the other anions. Formation of the spherical micelle-like nanostructure was seen for lengthened cations. Finally, the incorporation of an ester group into the alkyl side chain of the cation leads to stronger segregation between charged and uncharged networks, which consequently increased the possibility of self-assembly and micelle formation. PMID:27001746

  4. Synthesis and Site-Specific Incorporation of Red-Shifted Azobenzene Amino Acids into Proteins.

    Science.gov (United States)

    John, Alford A; Ramil, Carlo P; Tian, Yulin; Cheng, Gang; Lin, Qing

    2015-12-18

    A series of red-shifted azobenzene amino acids were synthesized in moderate-to-excellent yields via a two-step procedure in which tyrosine derivatives were first oxidized to the corresponding quinonoidal spirolactones followed by ceric ammonium nitrate-catalyzed azo formation with the substituted phenylhydrazines. The resulting azobenzene-alanine derivatives exhibited efficient trans/cis photoswitching upon irradiation with a blue (448 nm) or green (530 nm) LED light. Moreover, nine superfolder green fluorescent protein (sfGFP) mutants carrying the azobenzene-alanine analogues were expressed in E. coli in good yields via amber codon suppression with an orthogonal tRNA/PylRS pair, and one of the mutants showed durable photoswitching with the LED light.

  5. Modulational instability of incoherently coupled beams in azobenzene-containing polymer with photoisomerization nonlinearity

    Institute of Scientific and Technical Information of China (English)

    Zhang Bing-Zhi; Cui Hu; She Wei-Long

    2009-01-01

    The modulational instability of two incoherently coupled beams in azobenzene-containing polymer with photoisomerization nonlinearity is investigated analytically and numerically. Our results show that as a precursor to spatial optical soliton formation, modulational instability can be adjusted and controlled by the wavelength combinations of the signal and background beams. We also discuss the dependences of strength of modulational instability on intensities of two signal beams and background beam. These findings make it possible to predict the formation of incoherently coupled soliton pairs in azobenzene-containing polymer.

  6. Colorimetric response of azobenzene-terminated polydiacetylene vesicles under thermal and photic stimuli

    Science.gov (United States)

    You, Xian; Chen, Xin; Zou, Gang; Su, Wei; Zhang, Qijin; He, Pingsheng

    2009-11-01

    We study the colorimetric reversibility of pure polymerized p-nitro azobenzene moiety-substituted diacetylene (PNADA) and PNADA/polymerized 10,12-pentacosadiynoic acid (PDA) complex vesicles under thermal and photic stimuli. Because of the strong intermolecular interaction among azobenzene mesogens within the vesicles, PNADA vesicles show enhanced stability and completely reversible thermochromic response. Polydiacetylene based complex vesicles with partial reversible chromatic properties under both thermal and photonic stimuli were reported for the first time, which provided a novel model system for the understanding of the chromatic transition mechanism of polydiacetylene materials.

  7. Supramolecular effects in dendritic systems containing photoactive groups

    Directory of Open Access Journals (Sweden)

    GIANLUCA CAMILLO AZZELLINI

    2000-03-01

    Full Text Available In this article are described dendritic structures containing photoactive groups at the surface or in the core. The observed supramolecular effects can be attributed to the nature of the photoactive group and their location in the dendritic architecture. The peripheric azobenzene groups in these dendrimeric compounds can be regarded as single residues that retain the spectroscopic and photochemical properties of free azobenzene moiety. The E and Z forms of higher generation dendrimer, functionalized with azobenzene groups, show different host ability towards eosin dye, suggesting the possibility of using such dendrimer in photocontrolled host-guest systems. The photophysical properties of many dendritic-bipyridine ruthenium complexes have been investigated. Particularly in aerated medium more intense emission and a longer excited-state lifetime are observed as compared to the parent unsubstituted bipyridine ruthenium complexes. These differences can be attributed to a shielding effect towards dioxygen quenching originated by the dendritic branches.

  8. Synthesis of azobenzene-containing liquid crystalline gelator for use in liquid crystal gels

    Institute of Scientific and Technical Information of China (English)

    Guang Wang; Xiao Liang Zhao; Yue Zhao

    2008-01-01

    A liquid crystalline gelator containing the azobenzene chromophore was synthesized for the first time; it was used to form self-assembled network in nematic liquid crystals resulting in liquid crystal gels with distinct features.? 2008 Guang Wang. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

  9. Synthesis of Novel Amphiphilic Azobenzenes and X-ray Scattering Studies of Their Langmuir Monolayers

    DEFF Research Database (Denmark)

    Sørensen, Thomas Just; Kjær, Kristian; Breiby, Dag Werner;

    2008-01-01

    air-water interface, the amphiphilic azobenzenes form noncrystalline but stable Langmuir films that display an unusual reversible monolayer collapse close to 35 mN/m. The structures and phase transitions were studied by X-ray reflectivity (XR) and grazing-incidence X-ray diffraction, both utilizing...

  10. Light propagation through photoinduced chiral structures in azobenzene-containing polymers

    DEFF Research Database (Denmark)

    Nedelchev, L; Nikolova, L; Todorov, T;

    2001-01-01

    We investigate light propagation through azobenzene-containing polymers with photoinduced chiral structures. The structures have large pitch but the Mauguin condition is not fulfilled. The eigenmodes are shown to be elliptical and their ellipticity is determined by the ellipticity e(o) of the exc...

  11. Effect of heat and film thickness on a photoinduced phase transition in azobenzene liquid crystalline polyesters

    DEFF Research Database (Denmark)

    Sanchez, C; Alcala, R; Hvilsted, Søren;

    2003-01-01

    The liquid crystal to isotropic phase transition induced with 488 nm light in films of liquid crystalline azobenzene polyesters has been studied as a function of temperature, light intensity, and film thickness. That phase transition is associated with the photoinduced trans-cis-trans isomerizati......The liquid crystal to isotropic phase transition induced with 488 nm light in films of liquid crystalline azobenzene polyesters has been studied as a function of temperature, light intensity, and film thickness. That phase transition is associated with the photoinduced trans......-cis-trans isomerizations of azobenzene molecules and it has been found that the 488 nm light power needed to induce the transition to the isotropic state increases when the film thickness decreases. The irradiation with the laser beam heats the film up and this seems to be responsible for the observed thickness dependence....... Optical absorption measurements show that azobenzene aggregates present in one of the polymers are broken down in the photoinduced phase transition. The birefringence induced with low power 488 nm light in films before and after undergoing that photoinduced phase transition has also been studied...

  12. Self-assembled monolayers of azobenzene functionalized 1,3,5-triazine-4,6-dithiols

    International Nuclear Information System (INIS)

    Two novel azobenzene-functionalized 1,3,5-triazine-4,6-dithiols were synthesized and their ultrathin films were prepared by self-assembling (SA) technique. The switching between trans-and cis-forms was observed by measuring the surface potential using the Kelvin probe technique while alternating irradiation the SA monolayer (SAM) with ultraviolet or visible light

  13. Azobenzene mesogen-passivated gold nanoparticles: Controlled preparation, self-organized superstructures, thermal behavior and photoisomerization

    International Nuclear Information System (INIS)

    Liquid crystal nanoscience has aroused intensive interests mainly due to their unique and collective properties and a variety of potential applications. In this paper, gold nanoparticles (GNPs) coated with alkoxy azobenzene mesogenic thiol ligands of different length polymethylene spacer and linear alkyl thiol co-ligands have been prepared. The thermal properties, phase behavior of thus obtained hybrid GNPs and photophysical properties of their solid-state films have been investigated by differential scanning calorimetry (DSC), variable-temperature small and wide angle X-ray scattering (SAXS/WAXS) and UV–vis spectroscopy. The hybrid GNPs exclusively passivated with azobenzene mesogenic ligands showed lamellar structure while those with mixed ligands exhibited hexagonal columnar superstructure, and the latter complex hybrid GNPs exhibited noticeably improved thermolysis resistance. Moreover, it is very interesting that the solid-state films of the hybrid GNPs displayed reversible photoresponse owing to the trans–cis transformation of azobenzene mesogenic ligands, and compared with the hybrid GNPs coated with mesogenic ligands only, those with mixed ligands exhibited faster photoisomerization rate upon alternate UV and visible light irradiation, which may have some promising applications. - Graphical abstract: Gold nanoparticles (GNPs) coated with azobenzene mesogenic thiol ligands and linear alkyl thiol co-ligands have been prepared showing lamellar or hexagonal columnar superstructures. The complex hybrid GNPs with co-ligands exhibit much improved thermolysis resistance and the solid-state films of the hybrid GNPs display interesting reversible photoisomerization. - Highlights: • Gold nanoparticles (GNPs) coated with azobenzene thiol ligands have been prepared. • The hybrid GNPs with alkyl thiol co-ligands show enhanced thermolysis resistance. • The hybrid GNPs exhibit lamellar or hexagonal columnar superstructures. • The solid-state films of the hybrid

  14. Light-induced reversible modification of the work function of a new perfluorinated biphenyl azobenzene chemisorbed on Au (111)

    Science.gov (United States)

    Masillamani, Appan Merari; Osella, Silvio; Liscio, Andrea; Fenwick, Oliver; Reinders, Federica; Mayor, Marcel; Palermo, Vincenzo; Cornil, Jérôme; Samorì, Paolo

    2014-07-01

    We describe the synthesis of a novel biphenyl azobenzene derivative exhibiting: (i) a protected thiol anchoring group in the α-position to readily form self-assembled monolayers (SAMs) on Au surfaces; and (ii) a terminal perfluorinated benzene ring in the ω-position to modify the surface properties. The design of this molecule ensured both an efficient in situ photoswitching between the trans and cis isomers when chemisorbed on Au(111), due to the presence of a biphenyl bridge between the thiol protected anchoring group and the azo dye, and a significant variation of the work function of the SAM in the two isomeric states, induced by the perfluorinated phenyl head group. By exploiting the light responsive nature of the chemisorbed molecules, it is possible to dynamically modify in situ the work function of the SAM-covered electrode, as demonstrated both experimentally and by quantum-chemical calculations, revealing changes in work function up to 220 meV. These findings are relevant for tuning the work function of metallic electrodes, and hence to dynamically modulate charge injection at metal-semiconductor interfaces for organic opto-electronic applications.We describe the synthesis of a novel biphenyl azobenzene derivative exhibiting: (i) a protected thiol anchoring group in the α-position to readily form self-assembled monolayers (SAMs) on Au surfaces; and (ii) a terminal perfluorinated benzene ring in the ω-position to modify the surface properties. The design of this molecule ensured both an efficient in situ photoswitching between the trans and cis isomers when chemisorbed on Au(111), due to the presence of a biphenyl bridge between the thiol protected anchoring group and the azo dye, and a significant variation of the work function of the SAM in the two isomeric states, induced by the perfluorinated phenyl head group. By exploiting the light responsive nature of the chemisorbed molecules, it is possible to dynamically modify in situ the work function of

  15. PHOTOINDUCED ALIGNMENT OF OPTICALLY ACTIVE POLYMER CONTAINING A TEMPO RADICAL END GROUP

    Institute of Scientific and Technical Information of China (English)

    Hong-Chen Dong; Yong Zhang; Ze-da Xu; Xing-he Fan; Xiao-fang Chen; Xin-hua Wan; Qi-feng Zhou

    2003-01-01

    A new azobenzene side-chain polymer (TEMPO-PAZ) containing TEMPO (4-hydroxy-2,2,6,6-tetramethylpiperidinooxy) radical end group was synthesized by free radical copolymerization. Photoinduced alignment was studied on the polymer films at room temperature with linearly polarized light of 514.5 nm. The experimental results showed that the magnetic response intensity of the TEMPO-PAZ could be easily controlled by choosing the appropriate polarized light irradiating times, presumably due to the nitroxide radical in the TEMPO-PAZ molecular structure. For the polymer investigated here, the photoinduced alignment technique was introduced to increase the magnetic response intensity of polymer under irradiation, aiming originally at searching for a new photo-active organic magnetic multifunctionai materials.On the other hand, experimental results also showed that the TEMPO-PAZ can be used as a material for optical image storage.

  16. Thermochromism and structural change in polydiacetylenes including carboxy and 4-carboxyphenyl groups as the intermolecular hydrogen bond linkages in the side chain.

    Science.gov (United States)

    Tanioku, Chiaki; Matsukawa, Kimihiro; Matsumoto, Akikazu

    2013-02-01

    We investigated the thermochromic behavior of polydiacetylenes including the carboxy and 4-carboxyphenyl groups as the side-chain substituents adjacent to the conjugated main chain, and then, the thermal stability and the thermochromism reversibility of the polymers were related to changes in the polymer conformations monitored by IR and Raman spectroscopies and powder X-ray diffractions. The polydiacetylenes with no or a phenylene spacer between the main chain and the carboxylic acid moiety were revealed to exhibit a thermal resistance for maintaining reversible thermochromism in a high temperature range, rather than polydiacetylenes with a conventional structure with a flexible alkylene spacer. The molecular stacking structures of the diacetylenes and the corresponding polymers in the crystals were discussed based on the results of an X-ray single-crystal structure analysis as well as the powder X-ray diffraction measurements. PMID:23276165

  17. Discovery of 2-azetidinone and 1H-pyrrole-2,5-dione derivatives containing sulfonamide group at the side chain as potential cholesterol absorption inhibitors.

    Science.gov (United States)

    Yuan, Xinrui; Lu, Peng; Xue, Xiaojian; Qin, Hui; Fan, Chen; Wang, Yubin; Zhang, Qi

    2016-02-01

    Cholesterol absorption inhibitor (CAI) targeting Niemann-Pick C1-like1 protein was developed for the treatment of hyperlipidaemia and only ezetimibe was approved so far. For developing novel CAIs, we synthesized sixteen 2-azetidinone derivatives and thirteen 1H-pyrrole-2,5-dione derivatives containing sulfonamide group at the side chain, and their inhibitory activity of cholesterol absorption was evaluated in Caco-2 cell line in vitro. Furthermore, top six compounds were measured by cytotoxicity and partition coefficient, and 2-azetidinone analogue 9e was selected for in vivo study. Finally, 9e considerably reduced total cholesterol, LDL-C, FFA and triglyceride in the serum and increased the rate of HDL-C to total cholesterol, suggesting it could regulate the lipid metabolism and act as a potent CAI.

  18. Remarkable enhancement on elimination reaction of side groups in excimer laser ablation of mixture targets of perylene derivatives with metal powder

    International Nuclear Information System (INIS)

    Films are deposited on substrates at 20 deg.C by excimer laser ablation (ELA) of mixture targets of 3,4,9,10-perylenetetracarboxylic dianhydride (PTCDA) with metal powder, PTCDA/M (M=Co, Ni, Fe, W, Cu and Ag) using XeCl and ArF beams. Large amount of fragments with ''naked'' perylene skeletons can be produced owing to effective elimination of carboxylic dianhydride groups by ELA of PTCDA/Co both with XeCl and ArF beams under optimized ablation conditions. Elimination reaction of side groups of PTCDA is observed for ELA of the targets with metal powder of the iron group, Co, Fe and Ni, especially remarkable for Co and Fe. The film from PTCDA/Ni consists of small particles with the various diameters ranging from 10 to 100 nm as well as that from PTCDA/Co. Morphology like petal of rose can be seen everywhere for the film from PTCDA/Fe

  19. Photo-induced Alignment Behavior of Azobenzene-containing Polymer Films with Different Cross-linking Degree

    Institute of Scientific and Technical Information of China (English)

    Jing Shen; Jin-tang Huang; Yan-hua Luo; Qi-jin Zhang; Ke-yi Wang

    2008-01-01

    Three series of amorphous copolymers containing azobenzene groups with various substituents and certain amounts of crosslinkable acrylic groups were prepared. The cross-linked polymer films were obtained by thermal polymerization of the acrylic groups in the copolymers, during which, by controlling the time of cross-linking reaction, the films can be made with different cross-linking degree (from 0 to 32%, which was monitored by FT-IR spectra measurement). Photo-induced alignment process of the films was performed under irradiation with linearly polarized light at 442 nm, and the effect of cross-linking degree on the photo-induced alignment rate was investigated. The dynamics of the photo-induced alignment was analyzed with biexponential curve fitting. The photo-induced alignment rate and the maximum transmittance of the films decreased because of the cross-linking. Furthermore, for the cross-linked samples, it was found that their saturated value of transmittances keep constant after repeated "writing" and "erasing" cycles. The findings reveal that the cross-linking of the film can effectively restrain the phototactic mass transport of azopolymer during irradiation by polarized light. The relationship between the cross-linking degree and the photo-induced alignment behavior of azopolymer is discussed in detail.

  20. Incorporation of cyclic azobenzene into oligodeoxynucleotides for the photo-regulation of DNA hybridization.

    Science.gov (United States)

    Eljabu, Fatma; Dhruval, Joshi; Yan, Hongbin

    2015-12-01

    Cyclic azobenzene carboxylic acid was synthesized using a shortened route. After reaction with D-threolinol, the resulting cyclic azobenzene-D-threolinol (cAB-Thr) building block was transformed into the corresponding DMTr-protected phosphoramidite, and incorporated into oligodeoxynucleotides at various positions and frequencies by solid phase synthesis. The melting temperatures of these modified oligonucleotides were determined by UV spectrometry. Photo-regulation of cAB-Thr-modified oligonucleotides with their complementary sequence was evaluated by Fluorescence Resonance Energy Transfer experiments using a fluorescein-Black Hole Quencher pair. Results suggest that while cis-cAB destabilizes DNA duplexes, trans-cAB can be accommodated in double stranded DNA.

  1. Orientation of azobenzene molecules in polymer films induced by all-optical poling

    Institute of Scientific and Technical Information of China (English)

    Xiaoxia Zhong(钟晓霞); Shouyu Luo(罗售余); Xiuqin Yu(虞秀琴); Qu Li(李劬); Yingli Chen(陈英礼); Yu Sui(隋郁); Jie Yin(印杰)

    2003-01-01

    A model of the alignment of azobenzene molecules in polymer film induced by all-optical poling is proposedand verified by experiment. We found that when the writing beams of frequencies ω and 2ω are both linearlypolarized with their polarization directions parallel to each other, azobenzene molecules tend to reorientto the direction perpendicular to the writing beams polarization. At the end of the writing process, moremolecules orient to the direction perpendicular to the writing beams polarization than those which orientto the parallel direction. The alignment of molecules parallel or perpendicular to the polarization of thewriting beams is characteristic of polarity or no polarity, respectively. The alignment of molecules alongthe polarization of writing beams results in the second order nonlinearity in the polymer film. Accordingto the model, a new method to improve the optical poling efficiency is put forward.

  2. Novel azobenzene-phthalocyanine dyads——design of photo-modulated J-aggregation

    Institute of Scientific and Technical Information of China (English)

    NIU LiHong; ZHONG Cheng; CHEN ZiHui; ZHANG Zhi; LI ZhongYu; ZHANG FuShi; TANG YingWu

    2009-01-01

    Based on the J-aggregation mechanism of α-aryl/alkoxy-subetituted zinc phthalocyanines(Pcs) in non-coordinating solvents, two novel azobenzene-phthalocyanine dyads (3-azo-ZnPc and 4-azo-ZnPc) were synthesized with the aim of developing Pc compounds whose ability to form J-aggregation could be photo-modulated. It was found that 3-azo-ZnPc in chloroform could be effectively photo-controlled in a wide range. This phenomenon could be explained by the changes in the geometry and dipole moment of azobenzene during the photo-isomerization process. 4-azo-ZnPc did not have this ability at all, with or without UV light illumination. The positions of the oxygen atoms to which the aryl/alkoxy substitution was attached relatively were found important in determining the aggregation ability.

  3. Photoresponsive switches at surfaces based on supramolecular functionalization with azobenzene-oligoglycerol conjugates.

    Science.gov (United States)

    Nachtigall, Olaf; Kördel, Christian; Urner, Leonhard H; Haag, Rainer

    2014-09-01

    The synthesis, supramolecular complexation, and switching of new bifunctional azobenzene-oligoglycerol conjugates in different environments is reported. Through the formation of host-guest complexes with surface immobilized β-cyclodextrin receptors, the bifunctional switches were coupled to gold surfaces. The isomerization of the amphiphilic azobenzene derivatives was examined in solution, on gold nanoparticles, and on planar gold surfaces. The wettability of functionalized gold surfaces can be reversibly switched under light-illumination with two different wavelengths. Besides the photoisomerization processes and concomitant effects on functionality, the thermal cis to trans isomerization of the conjugates and their complexes was monitored. Thermal half-lives of the cis isomers were calculated for different environments. Surprisingly, the half-lives on gold nanoparticles were significantly smaller compared to planar gold surfaces. PMID:25044973

  4. Elucidation of Isomerization Pathways of a Single Azobenzene Derivative Using an STM.

    Science.gov (United States)

    Kazuma, Emiko; Han, Mina; Jung, Jaehoon; Oh, Junepyo; Seki, Takahiro; Kim, Yousoo

    2015-11-01

    The predominant pathway for the isomerization between cis- and trans-azobenzenes-either (i) inversion by the bending of an NNC bond or (ii) rotation by the torsion of two phenyl rings-continues to be a controversial topic. To elucidate each isomerization pathway, a strategically designed and synthesized azobenzene derivative was investigated on a Ag(111) surface. This was achieved by exciting the molecule with tunneling electrons from the tip of a scanning tunneling microscope (STM). Structural analyses of the molecularly resolved STM images reveal that both inversion and rotation pathways are available for isomerization on a metal surface and strongly depend on the initial adsorption structures of the molecule. On the basis of the potential energy diagrams for the isomerization, it is concluded that isomerization pathways on a metal surface are not simply related to the excited states. PMID:26722964

  5. Photoresponsive Release from Azobenzene-Modified Single Cubic Crystal NaCl/Silica Particles

    Directory of Open Access Journals (Sweden)

    Xingmao Jiang

    2011-01-01

    Full Text Available Azobenzene ligands were uniformly anchored to the pore surfaces of nanoporous silica particles with single crystal NaCl using 4-(3-triethoxysilylpropylureidoazobenzene (TSUA. The functionalization delayed the release of NaCl significantly. The modified particles demonstrated a photocontrolled release by trans/cis isomerization of azobenzene moieties. The addition of amphiphilic solvents, propylene glycol (PG, propylene glycol propyl ether (PGPE, and dipropylene glycol propyl ether (DPGPE delayed the release in water, although the wetting behavior was improved and the delay is the most for the block molecules with the longest carbon chain. The speedup by UV irradiation suggests a strong dependence of diffusion on the switchable pore size. TGA, XRD, FTIR, and NMR techniques were used to characterize the structures.

  6. Photoinduced reversible switching of porosity in molecular crystals based on star-shaped azobenzene tetramers.

    Science.gov (United States)

    Baroncini, Massimo; d'Agostino, Simone; Bergamini, Giacomo; Ceroni, Paola; Comotti, Angiolina; Sozzani, Piero; Bassanetti, Irene; Grepioni, Fabrizia; Hernandez, Taylor M; Silvi, Serena; Venturi, Margherita; Credi, Alberto

    2015-08-01

    The development of solid materials that can be reversibly interconverted by light between forms with different physico-chemical properties is of great interest for separation, catalysis, optoelectronics, holography, mechanical actuation and solar energy conversion. Here, we describe a series of shape-persistent azobenzene tetramers that form porous molecular crystals in their E-configuration, the porosity of which can be tuned by changing the peripheral substituents on the molecule. Efficient E→Z photoisomerization of the azobenzene units takes place in the solid state and converts the crystals into a non-porous amorphous melt phase. Crystallinity and porosity are restored upon Z→E isomerization promoted by visible light irradiation or heating. We demonstrate that the photoisomerization enables reversible on/off switching of optical properties such as birefringence as well as the capture of CO2 from the gas phase. The linear design, structural versatility and synthetic accessibility make this new family of materials potentially interesting for technological applications.

  7. Self-assembly of azobenzene bilayer membranes in binary ionic liquid-water nanostructured media.

    Science.gov (United States)

    Kang, Tejwant Singh; Ishiba, Keita; Morikawa, Masa-aki; Kimizuka, Nobuo

    2014-03-11

    Anionic azobenzene-containing amphiphile 1 (sodium 4-[4-(N-methyl-N-dodecylamino)phenylazo]benzenesulfonate) forms ordered bilayer membranes in binary ionic liquid (1-ethyl-3-methylimidazolium ethyl sulfate, [C2mim][C2OSO3])-water mixtures. The binary [C2mim][C2OSO3]-water mixture is macroscopically homogeneous at any mixing ratio; however, it possesses fluctuating nanodomains of [C2mim][C2OSO3] molecules as observed by dynamic light scattering (DLS). These nanodomains show reversible heat-induced mixing behavior with water. Although the amphiphile 1 is substantially insoluble in pure water, it is dispersible in the [C2mim][C2OSO3]-water mixtures. The concentration of [C2mim][C2OSO3] and temperature exert significant influences on the self-assembling characteristics of 1 in the binary media, as shown by DLS, transmission electron microscopy (TEM), UV-vis spectroscopy, and zeta-potential measurements. Bilayer membranes with rod- or dotlike nanostructures were formed at a lower content of [C2mim][C2OSO3] (2-30 v/v %), in which azobenzene chromophores adopt parallel molecular orientation regardless of temperature. In contrast, when the content of [C2mim][C2OSO3] is increased above 60 v/v %, azobenzene bilayers showed thermally reversible gel-to-liquid crystalline phase transition. The self-assembly of azobenzene amphiphiles is tunable depending on the volume fraction of [C2mim][C2OSO3] and temperature, which are associated with the solvation by nanoclusters in the binary [C2mim][C2OSO3]-water media. These observations clearly indicate that mixtures of water-soluble ionic liquids and water provide unique and valiant environments for ordered molecular self-assembly. PMID:24528277

  8. Recent advances towards azobenzene-based light-driven real-time information-transmitting materials

    OpenAIRE

    Jaume García-Amorós; Dolores Velasco

    2012-01-01

    Photochromic switches that are able to transmit information in a quick fashion have attracted a growing interest within materials science during the last few decades. Although very fast photochromic switching materials working within hundreds of nanoseconds based on other chromophores, such as spiropyranes, have been successfully achieved, reaching such fast relaxation times for azobenzene-based photochromic molecular switches is still a challenge. This review focuses on the most recent achie...

  9. Trans-cis photoisomerization of azobenzene by n→π* excitation:A semiclassical dynamics study

    Institute of Scientific and Technical Information of China (English)

    Shuai Yuan; Wei Feng Wu; Yusheng Dou; Jian She Zhao

    2008-01-01

    A realistic dynamics simulation study is reported for the trans-cis photoisomerization of azobenzene triggered by the n→π*excitation and the results show that the formation of cis isomer follows the rotational motion around the N=N bond.The simulation find that the CNN bond angle bending vibrations also play a significant role in the vibronic coupling between the HOMO and LUMO,which essentially leads a nonadiabatic transition of the molecule to the electronic ground state.

  10. Femtosecond pump-probe photoionization-photofragmentation spectroscopy of azobenzene cation

    Institute of Scientific and Technical Information of China (English)

    HO; JrWei

    2010-01-01

    We report the studies of ultrafast dynamics of azobenzene cations using femtosecond photoionization-photofragmentation spectroscopy. In our experiment,a femtosecond pump pulse first prepares an ensemble of azobenzene cations via photoionization of neutrals. A delayed probe pulse then brings the evolving ionic system to higher states that ultimately undergo ion fragmentation. The dynamics is followed by monitoring either the parent-ion depletion or fragment-ion formation as a function of the pump-probe delay time. The observed transients for azobenzene cations are characterized by a constant ion depletion modulated by a rapidly damped oscillatory signal with a period of about 1 ps. Theoretical calculations suggest that the oscillation arises from a vibration motion along the twisting inversion coordinate involving displacements in CNNC and phenyl-ring torsions. The oscillation is damped rapidly with a time constant of about 1.2 ps,suggesting that energy dissipation from the active mode to bath modes takes place on this time scale.

  11. Surface hopping dynamics of direct trans --> cis photoswitching of an azobenzene derivative in constrained adsorbate geometries

    Science.gov (United States)

    Floß, Gereon; Granucci, Giovanni; Saalfrank, Peter

    2012-12-01

    With ongoing miniaturization of electronic devices, the need for individually addressable, switchable molecules arises. An example are azobenzenes on surfaces which have been shown to be switchable between trans and cis forms. Here, we examine the "direct" (rather than substrate-mediated) channel of the trans → cis photoisomerization after ππ* excitation of tetra-tert-butyl-azobenzene physisorbed on surfaces mimicking Au(111) and Bi(111), respectively. In spirit of the direct channel, the electronic structure of the surface is neglected, the latter merely acting as a rigid platform which weakly interacts with the molecule via Van-der-Waals forces. Starting from thermal ensembles which represent the trans-form, sudden excitations promote the molecules to ππ*-excited states which are non-adiabatically coupled among themselves and to a nπ*-excited and the ground state, respectively. After excitation, relaxation to the ground state by internal conversion takes place, possibly accompanied by isomerization. The process is described here by "on the fly" semiclassical surface hopping dynamics in conjunction with a semiempirical Hamiltonian (AM1) and configuration-interaction type methods. It is found that steric constraints imposed by the substrate lead to reduced but non-vanishing, trans → cis reaction yields and longer internal conversion times than for the isolated molecule. Implications for recent experiments for azobenzenes on surfaces are discussed.

  12. Light-enhanced liquid-phase exfoliation and current photoswitching in graphene–azobenzene composites

    Science.gov (United States)

    Döbbelin, Markus; Ciesielski, Artur; Haar, Sébastien; Osella, Silvio; Bruna, Matteo; Minoia, Andrea; Grisanti, Luca; Mosciatti, Thomas; Richard, Fanny; Prasetyanto, Eko Adi; De Cola, Luisa; Palermo, Vincenzo; Mazzaro, Raffaello; Morandi, Vittorio; Lazzaroni, Roberto; Ferrari, Andrea C.; Beljonne, David; Samorì, Paolo

    2016-01-01

    Multifunctional materials can be engineered by combining multiple chemical components, each conferring a well-defined function to the ensemble. Graphene is at the centre of an ever-growing research effort due to its combination of unique properties. Here we show that the large conformational change associated with the trans–cis photochemical isomerization of alkyl-substituted azobenzenes can be used to improve the efficiency of liquid-phase exfoliation of graphite, with the photochromic molecules acting as dispersion-stabilizing agents. We also demonstrate reversible photo-modulated current in two-terminal devices based on graphene–azobenzene composites. We assign this tuneable electrical characteristics to the intercalation of the azobenzene between adjacent graphene layers and the resulting increase in the interlayer distance on (photo)switching from the linear trans-form to the bulky cis-form of the photochromes. These findings pave the way to the development of new optically controlled memories for light-assisted programming and high-sensitive photosensors. PMID:27052205

  13. 含侧基聚酯型聚氨酯耐水解性的研究%Hydrolysis-Resistance Research of Polyester Polyurethane with Different Side Groups

    Institute of Scientific and Technical Information of China (English)

    谢静; 杜中杰; 王慧荣; 励杭泉; 张晨

    2012-01-01

    According to the comparison of the mechanical properties hydrolysis resistance and of four kinds of polyurethane films with different side groups, it was indicated that the polyurethane film prepared from polyester polyols PEPO-EHO which was performed with 2-ethyl-l ,3-hexandiol (EHO) with a large alkyl side group and a-dipic acid performed higher hydrolytic stability, while the film prepared from polyester polyols PEPO-PPD which was performed with 1,3-propanediol (PPD) and adipic acid performed better mechanical properties. The PU film with both higher hydrolytic stability and better mechanical properties was fabricated by mixing PEPO-EHO with PEPO-PPD. With about 50% of the PEPO-PPD and PEPO-EHO respectively, the PU film exhibited the best comprehensive properties.%通过对比4种含有不同侧基结构的聚氨酯胶膜的力学性能和耐水解性,发现以含有较大 空间位阻侧基的2-乙基-1,3-己二醇与己二酸合成聚酯二元醇( PEPO-EHO)为原料制备的聚氨酯胶膜具有较优异的耐水解性,而以1,3-丙二醇与己二酸合成聚酯二元醇(PEPO-PPD)为原料制备的聚氨酯胶膜具有较好的力学性能.选取PEPO-EHO与PEPO-PPD混合后制备出的聚氨酯胶膜力学性能和耐水解性较好.当PEPO-EHO与PEPO-PPD在软段中混合的质量分数分别为50%时,所制备的聚氨酯胶膜具有较好的综合性能.

  14. Algebraic dependence of the structure factor and possible anharmonicity in a high-resolution x-ray study of a side-group polymeric liquid crystal

    Science.gov (United States)

    Nachaliel, E.; Keller, E. N.; Davidov, D.; Boeffel, C.

    1991-03-01

    We report on a high-resolution x-ray study of the smectic-A phase near the nematic-smectic-A transition of a side-group polymeric liquid crystal, polyacrylate. Except at the very near vicinity of the phase transition, the first- and the second-harmonic x-ray structure factors were found to be consistent with the harmonic theory of de Gennes and Caille. However, very close to the phase transition, the attempts to fit the two harmonics completely failed. We believe that this is evidence for the importance of anharmonic corrections near the phase transition. The fits to the experimental data yield the compressibility constant B and the splay elastic constant Ks. We found that B can be described by a power law B~tφ, where t=(Tc-T)/Tc, Tc being the phase-transition temperature. φ was found to be 0.82+/-0.08, in good agreement with theoretical predictions using exponents from the literature, but in disagreement with previous experimental results on monomeric liquid crystals. The splay elastic constant Ks has roughly the same magnitude as in monomeric liquid crystals but tends to decrease by approximately 50% upon approaching the transition from below. This temperature dependence is further evidence for the importance of anharmonicity in the system.

  15. Ab initio calculation of the electronic spectrum of azobenzene dyes and its impact on the design of optical data storage materials

    DEFF Research Database (Denmark)

    Åstrand, Per-Olof; Ramanujam, P.S.; Hvilsted, Søren;

    2000-01-01

    Electronic excitation energies of 16 azobenzene dyes have been calculated by ab initio methods within the second-order polarization propagator approximation (SOPPA). Good agreement with expriment is found for the lowest singlet and triplet states for both the trans- and cis-azobenzene molecules...... candidates for azo components used in materials for data storage....

  16. A chemical approach for site-specific identification of NMR signals from protein side-chain NH{sub 3}{sup +} groups forming intermolecular ion pairs in protein–nucleic acid complexes

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, Kurtis M. [University of Texas Health Science Center at Houston, Department of NanoMedicine and Biomedical Engineering and Institute of Molecular Medicine (United States); Nguyen, Dan; Esadze, Alexandre; Zandrashvili, Levani [University of Texas Medical Branch, Department of Biochemistry and Molecular Biology, Sealy Center for Structural Biology and Molecular Biophysics (United States); Gorenstein, David G. [University of Texas Health Science Center at Houston, Department of NanoMedicine and Biomedical Engineering and Institute of Molecular Medicine (United States); Iwahara, Junji, E-mail: juiwahar@utmb.edu, E-mail: j.iwahara@utmb.edu [University of Texas Medical Branch, Department of Biochemistry and Molecular Biology, Sealy Center for Structural Biology and Molecular Biophysics (United States)

    2015-05-15

    Protein–nucleic acid interactions involve intermolecular ion pairs of protein side-chain and DNA or RNA phosphate groups. Using three protein–DNA complexes, we demonstrate that site-specific oxygen-to-sulfur substitution in phosphate groups allows for identification of NMR signals from the protein side-chain NH{sub 3}{sup +} groups forming the intermolecular ion pairs. A characteristic change in their {sup 1}H and {sup 15}N resonances upon this modification (i.e., substitution of phosphate to phosphorodithioate) can represent a signature of an intermolecular ion pair. Hydrogen-bond scalar coupling between protein side-chain {sup 15}N and DNA phosphorodithiaote {sup 31}P nuclei provides direct confirmation of the intermolecular ion pair. The same approach is likely applicable to protein–RNA complexes as well.

  17. Photo-induced morphological winding and unwinding motion of nanoscrolls composed of niobate nanosheets with a polyfluoroalkyl azobenzene derivative.

    Science.gov (United States)

    Nabetani, Yu; Takamura, Hazuki; Uchikoshi, Akino; Hassan, Syed Zahid; Shimada, Tetsuya; Takagi, Shinsuke; Tachibana, Hiroshi; Masui, Dai; Tong, Zhiwei; Inoue, Haruo

    2016-06-16

    Photo-responsive nanoscrolls can be successfully fabricated by mixing a polyfluoroalkyl azobenzene derivative and a niobate nanosheet, which is exfoliated from potassium hexaniobate. In this study, we have found that the photo-responsive nanoscroll shows a morphological motion of winding and unwinding, which is basically due to the nanosheet sliding within the nanoscroll, by efficient photo-isomerization reactions of the intercalated azobenzene in addition to the interlayer distance change of the nanoscrolls. The relative nanosheet sliding of the nanoscroll is estimated to be ca. 280 nm from the AFM morphology analysis. The distance of the sliding motion is over 20 times that of the averaged nanosheet sliding in the azobenzene/niobate hybrid film reported previously. Photo-responsive nanoscrolls can be expected to be novel photo-activated actuators and artificial muscle model materials.

  18. Photo-induced morphological winding and unwinding motion of nanoscrolls composed of niobate nanosheets with a polyfluoroalkyl azobenzene derivative

    Science.gov (United States)

    Nabetani, Yu; Takamura, Hazuki; Uchikoshi, Akino; Hassan, Syed Zahid; Shimada, Tetsuya; Takagi, Shinsuke; Tachibana, Hiroshi; Masui, Dai; Tong, Zhiwei; Inoue, Haruo

    2016-06-01

    Photo-responsive nanoscrolls can be successfully fabricated by mixing a polyfluoroalkyl azobenzene derivative and a niobate nanosheet, which is exfoliated from potassium hexaniobate. In this study, we have found that the photo-responsive nanoscroll shows a morphological motion of winding and unwinding, which is basically due to the nanosheet sliding within the nanoscroll, by efficient photo-isomerization reactions of the intercalated azobenzene in addition to the interlayer distance change of the nanoscrolls. The relative nanosheet sliding of the nanoscroll is estimated to be ca. 280 nm from the AFM morphology analysis. The distance of the sliding motion is over 20 times that of the averaged nanosheet sliding in the azobenzene/niobate hybrid film reported previously. Photo-responsive nanoscrolls can be expected to be novel photo-activated actuators and artificial muscle model materials.Photo-responsive nanoscrolls can be successfully fabricated by mixing a polyfluoroalkyl azobenzene derivative and a niobate nanosheet, which is exfoliated from potassium hexaniobate. In this study, we have found that the photo-responsive nanoscroll shows a morphological motion of winding and unwinding, which is basically due to the nanosheet sliding within the nanoscroll, by efficient photo-isomerization reactions of the intercalated azobenzene in addition to the interlayer distance change of the nanoscrolls. The relative nanosheet sliding of the nanoscroll is estimated to be ca. 280 nm from the AFM morphology analysis. The distance of the sliding motion is over 20 times that of the averaged nanosheet sliding in the azobenzene/niobate hybrid film reported previously. Photo-responsive nanoscrolls can be expected to be novel photo-activated actuators and artificial muscle model materials. Electronic supplementary information (ESI) available: Fig. S1. Photo-isomerization reaction of nanoscrolls. See DOI: 10.1039/c6nr02177h

  19. Theoretical study of solvent effects on the ground and low-lying excited free energy surfaces of a push-pull substituted azobenzene.

    Science.gov (United States)

    Corchado, Jose C; Sánchez, M Luz; Fdez Galván, Ignacio; Martín, M Elena; Muñoz-Losa, Aurora; Barata-Morgado, Rute; Aguilar, Manuel A

    2014-10-30

    The ground and low-lying excited free energy surfaces of 4-amino-4'-cyano azobenzene, a molecule that has been proposed as building block for chiroptical switches, are studied in gas phase and a variety of solvents (benzene, chloroform, acetone, and water). Solvent effects on the absorption and emission spectra and on the cis-trans thermal and photo isomerizations are analyzed using two levels of calculation: TD-DFT and CASPT2/CASSCF. The solvent effects are introduced using a polarizable continuum model and a QM/MM method, which permits one to highlight the role played by specific interactions. We found that, in gas phase and in agreement with the results found for other azobenzenes, the thermal cis-trans isomerization follows a rotation-assisted inversion mechanism where the inversion angle must reach values close to 180° but where the rotation angle can take almost any value. On the contrary, in polar solvents the mechanism is controlled by the rotation of the CN═NC angle. The change in the mechanism is mainly related to a better solvation of the nitrogen atoms of the azo group in the rotational transition state. The photoisomerization follows a rotational pathway both in gas phase and in polar and nonpolar solvents. The solvent introduces only small modifications in the nπ* free energy surface (S1), but it has a larger effect on the ππ* surface (S2) that, in polar solvents, gets closer to S1. In fact, the S2 band of the absorption spectrum is red-shifted 0.27 eV for the trans isomer and 0.17 eV for the cis. In the emission spectrum the trend is similar: only S2 is appreciably affected by the solvent, but in this case a blue shift is found.

  20. Photomechanical Response of Composite Structures Built from Azobenzene Liquid Crystal Polymer Networks

    Directory of Open Access Journals (Sweden)

    Kyung Min Lee

    2011-09-01

    Full Text Available Optically directed shape adaptive responses have been sought after for many decades in photoresponsive polymeric materials. A number of recent examinations have elucidated elucidated the unique opportunities of photomechanical responses realized in azobenzene-functionalized liquid crystalline polymer networks (both elastomers and glasses. This work summarizes and contrasts the photomechanical response of glassy polydomain, monodomain, and twisted nematic azo-LCN materials to blue-green irradiation. Building from this summary, the combinatorial photomechanical response observed upon irradiation of composite cantilevers is examined. Large scale shape adaptations are realized, with novel responses that may be of potential use in future employment of these materials in actuation.

  1. Second-order nonlinear optical properties of mexylaminotriazine-functionalized glass-forming azobenzene derivatives

    Science.gov (United States)

    Umezawa, Hirohito; Jackson, Matthew; Lebel, Olivier; Nunzi, Jean-Michel; Sabat, Ribal Georges

    2016-10-01

    The second-order nonlinear optical coefficients of thin films of mexylaminotriazine-functionalized azobenzene molecular glass derivatives were measured using second harmonic generation. The thin films were poled using a custom corona poling set-up and the second harmonic light from a pulsed 1064-nm laser was detected. Four out of the six tested compounds showed optical nonlinearity and a maximum coefficient of 75 pm/V was obtained. The time dependence of the nonlinear coefficients was studied under ambient light and under dark; the second harmonic generation intensity stayed constant for thiazole-containing derivatives while a significant decay was measured for the other compounds.

  2. Azobenzene Polyesters Used as Gate‐Like Scaffolds in Nanoscopic Hybrid Systems

    DEFF Research Database (Denmark)

    Bernardos, Andrea; Mondragón, Laura; Javakhishvili, Irakli;

    2012-01-01

    The synthesis and characterisation of new capped silica mesoporous nanoparticles for on‐command delivery applications is reported. Functional capped hybrid systems consist of MCM‐41 nanoparticles functionalised on the external surface with polyesters bearing azobenzene derivatives and rhodamine B...... inside the mesopores. Two solid materials, Rh‐PAzo8‐S and Rh‐PAzo6‐S, containing two closely related polymers, PAzo8 and PAzo6, in the pore outlets have been prepared. Materials Rh‐PAzo8‐S and Rh‐PAzo6‐S showed an almost zero release in water due to steric hindrance imposed by the presence of anchored...

  3. Synthesis and Characterization of Nonsymmetric Liquid Crystal Dimer Containing Biphenyl and Azobenzene Moiety

    Directory of Open Access Journals (Sweden)

    S. Sandy Subala

    2013-01-01

    Full Text Available Calamitic liquid crystalline dimer containing azobenzene moiety and a decyloxy biphenyl linked by flexible spacers {4-[7-(4′-decyloxy-biphenyl-4-yloxy-alkyloxy]-phenyl}-(4-decyl-phenyl-diazene has been synthesized and characterized by spectroscopic methods. The transition temperatures and phase behaviours were studied by Differential Scanning Calorimeter (DSC and Polarizing Optical Microscope (POM. The synthesized compounds exhibited enantiotropic liquid crystal phase with higher spacer display nematic and smectic C phases while lower spacer shows nematic and smectic A phases.

  4. Azobenzene Modified Imidacloprid Derivatives as Photoswitchable Insecticides: Steering Molecular Activity in a Controllable Manner

    Science.gov (United States)

    Xu, Zhiping; Shi, Lina; Jiang, Danping; Cheng, Jiagao; Shao, Xusheng; Li, Zhong

    2015-10-01

    Incorporating the photoisomerizable azobenzene into imidacloprid produced a photoswitchable insecticidal molecule as the first neonicotinoid example of remote control insecticide performance with spatiotemporal resolution. The designed photoswitchable insecticides showed distinguishable activity against Musca both in vivo and in vitro upon irradiation. Molecular docking study further suggested the binding difference of the two photoisomers. The generation of these photomediated insecticides provides novel insight into the insecticidal activity facilitating further investigation on the functions of insect nicotinic acetylcholine receptors and opens a novel way to control and study insect behavior on insecticide poisoning using light.

  5. Photomodulation of fluoride ion binding through anion-π interactions using a photoswitchable azobenzene system

    Science.gov (United States)

    Rananaware, Anushri; Samanta, Mousumi; Bhosale, Rajesh S.; Kobaisi, Mohammad Al; Roy, Biswajit; Bheemireddy, Varun; Bhosale, Sidhanath V.; Bandyopadhyay, Subhajit; Bhosale, Sheshanath V.

    2016-03-01

    The discovery of photoswitchable azobenzene-systems that undergo trans-to-cis photoisomerisation was a milestone in supramolecular chemistry. Such photoswitches have possible applications in data storage, stimuli responsive delivery systems, and molecular machines due to fast and selective switching. However, the light induced cis isomer of azobenzene is rather unstable and reverts thermally and photochemically to the thermodynamically stable trans configuration. We report, for the first time, controlled photoswitching of an azo-naphthalenediimide (azo-NDI) which can be achieved upon binding of fluoride ions through anion-π interaction. This NDI-F–NDI “sandwich” stabilises the cis configuration through the generation of an NDI•‑ radical anion, and a dianionic, NDI2‑ species that becomes unusually stable in the cis form. The sandwiched cis form reverts to the trans form only upon decomplexation of F‑. A model pollutant was successfully degraded using the photogenerated NDI-F–NDI sandwich. This opens a wide range of applications in molecular and supramolecular nanotechnology.

  6. Remarkable enhancement of the photoreactivity of a polyfluoroalkyl azobenzene derivative in an organic-inorganic nano-layered microenvironment.

    Science.gov (United States)

    Ramakrishnan, Vivek; Yamamoto, Daisuke; Sasamoto, Shin; Shimada, Tetsuya; Nabetani, Yu; Tachibana, Hiroshi; Inoue, Haruo

    2014-11-21

    Organic-inorganic hybrids composed of polyfluoroalkyl azobenzene surfactant (abbreviated as C3F-Azo-C6H) and inorganic layered compounds are able to undergo reversible three-dimensional morphology changes such as interlayer space changes and nanosheet sliding in a giant scale due to reversible trans-cis isomerization of the azobenzene moiety upon photo-irradiation. In this paper, we have systematically studied the relationship between the layered hybrid microstructures of C3F-Azo-C6H-clay and their photoreactivity for understanding the mechanism of the photo-induced morphology change. The photoreactivity was found to be very much affected by the surrounding microenvironments. As compared with it in solution, the cis-trans photo-isomerization in C3F-Azo-C6H-clay nano-layered film was substantially enhanced with the quantum yield exceeding unity (Φ = 1.9), while the trans-cis isomerization was rather retarded. The corresponding hydrocarbon analogue of the azobenzene surfactant (C3H-Azo-C6H) did not show such an enhancement. The enhancement was discussed in terms of a cooperative effect among adjacent azobenzene moieties along with polyfluoroalkyl chains and the inorganic clay nanosheet to prevent a dissipation of the excess energy being liberated during the photo-isomerization within the nano-layered microenvironment.

  7. 10,000 optical write, read, and erase cycles in an azobenzene sidechain liquid-crystalline polyester

    DEFF Research Database (Denmark)

    Holme, NCR; Ramanujam, P.S.; Hvilsted, Søren

    1996-01-01

    We show far what is believed to he the first time that it is possible tu generate 10,000 rapid write, read, and erase cycles optically in an azobenzene sidechain liquid-crystalline polyester. We do this by exposing the film alternately to visible light from an argon laser at 488 nm and ultraviolet...

  8. NETWORK CROWN ETHER POLYMERS WITH CENTRIC FUNCTIONAL GROUPS.Ⅱ.SYNTHESIS OF NETROWK CROWN ETHER POLYMER WITH PENDANT SULFIDE SIDE CHAIN AND ITS PLATINUM COMPLEX

    Institute of Scientific and Technical Information of China (English)

    CHENYuanyin; MENGLingzhi; 等

    1995-01-01

    Network crown ether polymer with pendant sulfide side chain in the network structure units has been synthesized via ring-opening copolymerization of β-ethylthioethyl glycidyl ether and diethylene glycol bisglycidyl ether.A kind of active catalyst suitable for this reaction was suggested.The title polymer was found to be a good ligand for platinous chloride,and the platinous complex could catalyze the hydrosilylation of ole fins with triethoxysilane efficiently.

  9. Unusual Photo-Induced Behaviour in a Side Chain Liquid Crystalline Azo-Polyester

    DEFF Research Database (Denmark)

    López, D; Rodríguez, F.J.; Sánchez, C.;

    2006-01-01

    An unusual behaviour has been observed in the photo-indueed response of an azobenzene side chain liquid erystalline polyester (P6d4). Room temperature irradiation with linearly polarised 488 nm light does not induce any birefringence (An) in films of this polymer that have been quenehed from...... the isotropie state. However, using the same irradiation conditions An is indueed in quenehed films that have been kept in darkness for a few minutes. Besides, no photo-induced An is observed in films irradiated with 488 nm light that have been previously irradiated with UV light. In this ease, An can...

  10. Preparation of mesoporous SiO2@azobenzene-COOH chemoselective nanoprobes for comprehensive mapping of amino metabolites in human serum.

    Science.gov (United States)

    Li, Hua; Qin, Qian; Qiao, Lizhen; Shi, Xianzhe; Xu, Guowang

    2015-06-30

    A novel type of mesoporous SiO2@H4/D4 tagged azobenzene-COOH chemoselective nanoprobe was developed for comprehensive mapping of amino metabolites in complex biological samples with high specificity and sensitivity.

  11. Azo···phenyl stacking: a persistent self-assembly motif guides the assembly of fluorinated cis-azobenzenes into photo-mechanical needle crystals.

    Science.gov (United States)

    Bushuyev, Oleksandr S; Tomberg, Anna; Vinden, Joanna R; Moitessier, Nicolas; Barrett, Christopher J; Friščić, Tomislav

    2016-02-01

    We describe a novel, persistent motif of molecular assembly in photo-mechanical crystals and cocrystals of fluorinated cis-azobenzenes. The azo···phenyl stacking, preserved upon either chemical substitution or halogen-bonded cocrystallization, guides the assembly of fluorinated cis-azobenzenes into columnar stacks and drives the formation of crystals with needle-like morphologies optimal for photo-mechanical motion. PMID:26691226

  12. Side Effects of Chemotherapy

    Science.gov (United States)

    ... Men Living with Prostate Cancer Side Effects of Chemotherapy Side Effects Urinary Dysfunction Bowel Dysfunction Erectile Dysfunction ... Side Effects of Hormone Therapy Side Effects of Chemotherapy Side Effects: When to Seek Help PSA Rising ...

  13. Photoinduced optical anisotropy in azobenzene methacrylate block copolymers: Influence of molecular weight and irradiation conditions

    DEFF Research Database (Denmark)

    Gimeno, Sofia; Forcen, Patricia; Oriol, Luis;

    2009-01-01

    The photoinduced anisotropy in a series of azomethacrylate block copolymers with different Molecular weights and azo contents has been investigated under several irradiation conditions. Depending on molecular weight and composition, different microstructures (disordered, lamellar, spherical) appear...... the copolymers in which azobenzene units segregate to nano spheres and the lowest (and less stable) Delta n(N) values, appear in disordered systems not showing any defined microstructure. Besides, higher Delta n(N) is obtained in the copolymers with larger molecular weight of the poly (methyl......) and light power (from 100 to 500 mW/cm(2)) also influence the photoinduced response. Photoinduced Delta n(N) growth rate is faster when both temperature and irradiation power increase. Furthermore, birefringence is only induced at temperatures up to 90 degrees C, the maximum value being obtained at...

  14. Near-field lithography on the azobenzene polymer liquid crystal films

    Institute of Scientific and Technical Information of China (English)

    Douguo Zhang; Jian Liu; Zebo Zhang; Li Cao; Anlian Pan; Pei Wang; Yonghua Lu; Ming Bai; Jun Yang; Lin Tang; Jiangying Zhang; Hai Ming; Qijin Zhang

    2005-01-01

    @@ In this article, we reported near-field research on azobenzene polymer liquid crystal films using scanning near-field optical microscopy (SNOM). Optical writing and subsequently topographic reading of the patterns with subwavelength resolution were carried out in our experiments. Nanometer scale dots and lines were successfully fabricated on the films and the smallest dot diameter is about 120 nm. The width of the line fabricated is about 250 nm. This method is also a choice for nanolithography. The mechanism of the surface deformation on the polymer films was briefly analyzed from the viewpoint of gradient force in the optical near field. The intensity distribution of the electric field near the tip aperture was numerically simulated using finite-difference time-domain (FDTD) method and the numerical simulation results were consistent with the experimental results.

  15. Snowmass Cosmic Frontiers 6 (CF6) Working Group Summary --The Bright Side of the Cosmic Frontier: Cosmic Probes of Fundamental Physics

    CERN Document Server

    Beatty, J J; Olinto, A; Sinnis, G; Abeysekara, A U; Anchordoqui, L A; Aramaki, T; Belz, J; Buckley, J H; Byrum, K; Cameron, R; Chen, M-C; Connolly, A; Cowen, D; DeYoung, T; Dumm, P von Doetinchem J; Errando, M; Farrar, G; Ferrer, F; Fortson, L; Funk, S; Grant, D; Griths, S; Hailey, C; Hogan, C; Holder, J; Humensky, B; Kaaret, P; Klein, S R; Krennrich, H Krawczynski F; Krizmanic, J; Kusenko, A; Linnemann, J T; MacGibbon, J H; Matthews, J; McCann, A; Mitchell, J; Mukherjee, R; Nitz, D; Ong, R A; Orr, M; Otte, N; Paul, T; Sanchez-Conde, M A; Sokolsky, P; Stecker, F; Stump, D; Taboada, I; Thomson, G B; Tollefson, K; von Doetinchem, P; Ukwatta, T; Vandenbroucke, J; Vasileiou, V; Vassileiv, V V; Weiler, T J; Williams, D A; Weinstein, A; Wood, M; Zitzer, B

    2013-01-01

    Report of the CF6 Working Group at Snowmass 2013. Topics addressed include ultra-high energy cosmic rays, neutrinos, gamma rays, baryogenesis, and experiments probing the fundamental nature of spacetime.

  16. Large work function shift of gold induced by a novel perfluorinated azobenzene-based self-assembled monolayer.

    Science.gov (United States)

    Crivillers, Núria; Osella, Silvio; Van Dyck, Colin; Lazzerini, Giovanni M; Cornil, David; Liscio, Andrea; Di Stasio, Francesco; Mian, Shabbir; Fenwick, Oliver; Reinders, Federica; Neuburger, Markus; Treossi, Emanuele; Mayor, Marcel; Palermo, Vincenzo; Cacialli, Franco; Cornil, Jérôme; Samorì, Paolo

    2013-01-18

    Tune it with light! Self-assembled monolayers on gold based on a chemisorbed novel azobenzene derivative with a perfluorinated terminal phenyl ring are prepared. The modified substrate shows a significant work function increase compared to the bare metal. The photo-conversion between trans and cis isomers chemisorbed on the surface shows great perspectives for being an accessible route to tune the gold properties by means of light.

  17. Asymmetric Dimers of Chiral Azobenzene Dopants Exhibiting Unusual Helical Twisting Power upon Photoswitching in Cholesteric Liquid Crystals.

    Science.gov (United States)

    Kim, Yuna; Tamaoki, Nobuyuki

    2016-02-01

    In this study, we synthesized asymmetric dimeric chiral molecules as photon-mode chiral switches for reversible tuning of self-assembled helical superstructures. The chiral switches bearing two mesogen units-cholesterol and azobenzene moieties connected through flexible alkylenedioxy bridges-were doped into nematic liquid crystals, resulting in a chiral nematic (cholesteric) phase. Under irradiation with UV light, photoisomerization of the azobenzene units led to unprecedented switching of the cholesteric pitch and helical twisting power (HTP, β), with a higher HTP found in the cis-rich state (bent-form) than in the trans-state (rod-form). We attribute this behavior to the elongated cybotactic smectic clusters disrupting the helical orientation of the molecules in the cholesteric liquid crystals; their reversible decay and reassembly was evidenced upon sequential irradiation with UV and visible light, respectively. In addition to the photoisomerization of the azobenzene units, the odd/even parity of the alkylenedioxy linkers of the dimeric dopants also had a dramatic effect on the transitions of the cybotactic smectic domains. On the basis of the large rotational reorganization of the cholesteric helix and HTP switching (Δβ/βini of up to 50%), we could control the macroscopic rotational motion of microsized glass rods upon irradiating the surface of a cholesteric liquid crystal film featuring a polygonal fingerprint texture using UV and visible light. PMID:26815738

  18. Surface hopping dynamics of direct trans → cis photoswitching of an azobenzene derivative in constrained adsorbate geometries.

    Science.gov (United States)

    Floß, Gereon; Granucci, Giovanni; Saalfrank, Peter

    2012-12-21

    With ongoing miniaturization of electronic devices, the need for individually addressable, switchable molecules arises. An example are azobenzenes on surfaces which have been shown to be switchable between trans and cis forms. Here, we examine the "direct" (rather than substrate-mediated) channel of the trans → cis photoisomerization after ππ∗ excitation of tetra-tert-butyl-azobenzene physisorbed on surfaces mimicking Au(111) and Bi(111), respectively. In spirit of the direct channel, the electronic structure of the surface is neglected, the latter merely acting as a rigid platform which weakly interacts with the molecule via Van-der-Waals forces. Starting from thermal ensembles which represent the trans-form, sudden excitations promote the molecules to ππ∗-excited states which are non-adiabatically coupled among themselves and to a nπ∗-excited and the ground state, respectively. After excitation, relaxation to the ground state by internal conversion takes place, possibly accompanied by isomerization. The process is described here by "on the fly" semiclassical surface hopping dynamics in conjunction with a semiempirical Hamiltonian (AM1) and configuration-interaction type methods. It is found that steric constraints imposed by the substrate lead to reduced but non-vanishing, trans → cis reaction yields and longer internal conversion times than for the isolated molecule. Implications for recent experiments for azobenzenes on surfaces are discussed. PMID:23267492

  19. A possibility of a protein-bound water molecule as the ionizable group responsible for pKe at the alkaline side in human matrix metalloproteinase 7 activity.

    Science.gov (United States)

    Morishima, Aiko; Yasukawa, Kiyoshi; Inouye, Kuniyo

    2012-05-01

    Human matrix metalloproteinase 7 (MMP-7) activity exhibits broad bell-shaped pH profile with the acidic and alkaline pK(a) (pK(e1) and pK(e2)) values of about 4 and 10. The ionizable group for pK(e2) was assigned to Lys or Arg by thermodynamic analysis; however, no such residues are present in the active site. Hence, based on the crystal structure, we hypothesized that a water molecule bound to the main-chain nitrogen of Ala162 (W1) or the main-chain carbonyl oxygen of Pro217 (W2) is a candidate for the ionizable group for pK(e2) [Takeharu, H. et al. (2011) Biochim. Biophys. Acta 1814, 1940-1946]. In this study, we inspected this hypothesis. In the hydrolysis of (7-methoxycoumarin-4-yl)acetyl-L-Pro-L-Leu-Gly-L-Leu-[N(3)-(2,4-dinitrophenyl)-L-2,3-diaminopropionyl]-L-Ala-L-Arg-NH(2), all 19 variants, in which one of all Lys and Arg residues was replaced by Ala, retained activity, indicating that neither Lys nor Arg is the ionizable group. pK(e2) values of A162S, A162V and A162G were 9.6 ± 0.1, 9.5 ± 0.1 and 10.4 ± 0.2, respectively, different from that of wild-type MMP-7 (WT) (9.9 ± 0.1) by 0.3-0.5 pH unit, and those of P217S, P217V and P217G were 10.1 ± 0.1, 9.8 ± 0.1 and 9.7 ± 0.1, respectively, different from that of WT by 0.1-0.2 pH unit. These results suggest a possibility of W1 or W2 as the ionizable group for pK(e2).

  20. The dark side of the $\\mu$: on multiple solutions to renormalisation group equations, and why the CMSSM is not necessarily being ruled out

    CERN Document Server

    Allanach, B C; Gripaios, Ben

    2013-01-01

    When solving renormalisation group equations in a quantum field theory, one often specifies the boundary conditions at multiple renormalisation scales, such as the weak and grand-unified scales in a theory beyond the standard model. A point in the parameter space of such a model is usually specified by the values of couplings at these boundaries of the renormalisation group flow, but there is no theorem guaranteeing that such a point has a unique solution to the associated differential equations, and so there may exist multiple, phenomenologically distinct solutions, all corresponding to the same point in parameter space. We show that this is indeed the case in the constrained minimal supersymmetric standard model (CMSSM), and we exhibit such solutions, which cannot be obtained using out-of-the-box computer programs in the public domain. Some of the multiple solutions we exhibit have CP-even lightest Higgs mass predictions between 124 and 126 GeV. Without an exhaustive 8-dimensional MSSM parameter scan per CM...

  1. Photocontrol of Voltage-Gated Ion Channel Activity by Azobenzene Trimethylammonium Bromide in Neonatal Rat Cardiomyocytes.

    Directory of Open Access Journals (Sweden)

    Sheyda R Frolova

    Full Text Available The ability of azobenzene trimethylammonium bromide (azoTAB to sensitize cardiac tissue excitability to light was recently reported. The dark, thermally relaxed trans- isomer of azoTAB suppressed spontaneous activity and excitation propagation speed, whereas the cis- isomer had no detectable effect on the electrical properties of cardiomyocyte monolayers. As the membrane potential of cardiac cells is mainly controlled by activity of voltage-gated ion channels, this study examined whether the sensitization effect of azoTAB was exerted primarily via the modulation of voltage-gated ion channel activity. The effects of trans- and cis- isomers of azoTAB on voltage-dependent sodium (INav, calcium (ICav, and potassium (IKv currents in isolated neonatal rat cardiomyocytes were investigated using the whole-cell patch-clamp technique. The experiments showed that azoTAB modulated ion currents, causing suppression of sodium (Na+ and calcium (Ca2+ currents and potentiation of net potassium (K+ currents. This finding confirms that azoTAB-effect on cardiac tissue excitability do indeed result from modulation of voltage-gated ion channels responsible for action potential.

  2. Optical storage in azobenzene-containing epoxy polymers processed as Langmuir Blodgett films

    Energy Technology Data Exchange (ETDEWEB)

    Fernández, Raquel; Mondragon, Iñaki [‘Materials - Technologies’ Group, Department of Chemical and Environmental Engineering, Polytechnic School, Universidad País Vasco/Euskal Herriko Unibertsitatea, Pza Europa 1, 20018 Donostia-San Sebastián (Spain); Sanfelice, Rafaela C.; Pavinatto, Felippe J.; Oliveira, Osvaldo N. [Instituto de Física de São Carlos, Universidade de São Paulo, Av. Trabalhador São Carlense, 400, Centro, CEP 13560-970, São Carlos (Brazil); Oyanguren, Patricia [Institute of Materials Science and Technology (INTEMA), University of Mar del Plata and National Research Council (CONICET), J. B. Justo 4302, 7600 Mar del Plata (Argentina); Galante, María J., E-mail: galant@fi.mdp.edu.ar [Institute of Materials Science and Technology (INTEMA), University of Mar del Plata and National Research Council (CONICET), J. B. Justo 4302, 7600 Mar del Plata (Argentina)

    2013-04-01

    In this study, azocopolymers containing different main-chain segments have been synthesized with diglycidyl ether of bisphenol A (DGEBA, DER 332, n = 0.03) and the azochromophore Disperse Orange 3 (DO3) cured with two monoamines, viz. benzylamine (BA) and m-toluidine (MT). The photoinduced birefringence was investigated in films produced with these azopolymers using the spin coating (SC) and Langmuir Blodgett (LB) techniques. In the LB films, birefringence increased with the content of azochromophore and the film thickness, as expected. The nanostructured nature of the LB films led to an enhanced birefringence and faster dynamics in the writing process, compared to the SC films. In summary, the combination of azocopolymers and the LB method may allow materials with tuned properties for various optical applications, including in biological systems were photoisomerization may be used to trigger actions such as drug delivery. Highlights: ► Langmuir Blodgett (LB) films of epoxy-based azopolymers were obtained and analyzed. ► Optical properties of LB and spin coated (SC) films were compared. ► Azo content, structure, laser power and number of layers were main factors studied. ► LB films had larger free volume for the azobenzenes isomerization than SC. ► LB films led to higher birefringence and faster dynamics compared to SC.

  3. Study on the prediction of visible absorption maxima of azobenzene compounds

    Institute of Scientific and Technical Information of China (English)

    LIU Jun-na; CHEN Zhi-rong; YUAN Shen-feng

    2005-01-01

    The geometries of azobenzene compounds are optimized with B3LYP/6-311 G* method, and analyzed with nature bond orbital, then their visible absorption maxima are calculated with TD-DFT method and ZINDO/S method respectively. The results agree well with the observed values. It was found that for the calculation of visible absorption using ZINDO/S method could rapidly yield better results by adjusting OWFπ-π (the relationship between π-π overlap weighting factor) value than by the TD-DFT method. The method of regression showing the linear relationship between OWFπ-π and BLN-N (nitrogen-nitrogen bond lengths) as OWFπ-π=-8.1537+6.5638BLN-N, can be explained in terms of quantum theory, and also be used for prediction of visible absorption maxima of other azobenzne dyes in the same series. This study on molecules' orbital geometry indicates that their visible absorption maxima correspond to the electron transition from HOMO (the highest occupied molecular orbital) to LUMO (the lowest unoccupied molecular orbital).

  4. Thermal and Electronic Fluctuations of Flexible Adsorbed Molecules: Azobenzene on Ag(111)

    Science.gov (United States)

    Maurer, Reinhard J.; Liu, Wei; Poltavsky, Igor; Stecher, Thomas; Oberhofer, Harald; Reuter, Karsten; Tkatchenko, Alexandre

    2016-04-01

    We investigate the thermal and electronic collective fluctuations that contribute to the finite-temperature adsorption properties of flexible adsorbates on surfaces on the example of the molecular switch azobenzene C12 H10 N2 on the Ag(111) surface. Using first-principles molecular dynamics simulations, we obtain the free energy of adsorption that accurately accounts for entropic contributions, whereas the inclusion of many-body dispersion interactions accounts for the electronic correlations that govern the adsorbate binding. We find the adsorbate properties to be strongly entropy driven, as can be judged by a kinetic molecular desorption prefactor of 1024 s-1 that largely exceeds previously reported estimates. We relate this effect to sizable fluctuations across structural and electronic observables. A comparison of our calculations to temperature-programed desorption measurements demonstrates that finite-temperature effects play a dominant role for flexible molecules in contact with polarizable surfaces, and that recently developed first-principles methods offer an optimal tool to reveal novel collective behavior in such complex systems.

  5. Collision induced dissociation study of azobenzene and its derivatives: computational and experimental results

    Science.gov (United States)

    Rezaee, Mohammadreza; Compton, Robert

    2015-03-01

    Experimental and computational investigation have been performed in order to study the bond dissociation energy of azobenzene and its derivatives using collision induced dissociation method as well as other energy and structural characteristics. The results have been verified by comparing with results obtained from computational quantum chemistry. We used different density functional methods as well as the Möller-Plesset perturbation theory and the coupled cluster methods to explore geometric, electronic and the spectral properties of the sample molecules. Geometries were calculated and optimized using the 6-311 + + G(2d,2p) basis set and the B3LYP level of theory and these optimized structures have been subjected to the frequency calculations to obtain thermochemical properties by means of different density functional, Möller-Plesset, and coupled cluster theories to obtain a high accuracy estimation of the bond dissociation energy value. The results from experiments and the results obtained from computational thermochemistry are in close agreement. Physics and Astronomy Department

  6. Photochromic molecular gyroscope with solid state rotational states determined by an azobenzene bridge.

    Science.gov (United States)

    Commins, Patrick; Garcia-Garibay, Miguel A

    2014-02-21

    We describe the synthesis, characterization, photochemical isomerization, and rotational dynamics of a crystalline molecular gyroscope containing an azobenzene bridge (trans-2) that spans from one end of the stator to other, with the intention of exploring its function as a molecular brake. While single crystal X-ray diffraction analysis of a photochemically inactive dichloromethane solvate was used to confirm the molecular and packing structures of trans-2, a nanocrystalline pseudopolymorph was shown to be photoactive, and it was analyzed by powder X-ray diffraction (PXRD), scanning electron microscopy, and variable temperature solid state (2)H NMR before and after photoisomerization. It was shown that the nanocrystalline suspension irradiated with λ = 340 nm reaches a photostationary state with 34% of cis-isomer, as compared to that observed in solution where the corresponding value is 74%. Line shape analysis of solid state (2)H NMR spectra of a phenylene-d4 isotopologue, obtained as a function of temperature, indicated that rotation in crystals of the trans-2 isomer, with a mean activation energy of 4.6 ± 0.6 kcal/mol and a pre-exponential factor exp(29.4 ± 1.7), is ten times faster than that of samples containing the cis-2 isomer, which has a higher mean activation energy of 5.1 ± 0.6 kcal/mol and a lower pre-exponential factor of exp(27.9 ± 1.3).

  7. Fast photodynamics of azobenzene probed by scanning excited-state potential energy surfaces using slow spectroscopy.

    Science.gov (United States)

    Tan, Eric M M; Amirjalayer, Saeed; Smolarek, Szymon; Vdovin, Alexander; Zerbetto, Francesco; Buma, Wybren Jan

    2015-01-01

    Azobenzene, a versatile and polymorphic molecule, has been extensively and successfully used for photoswitching applications. The debate over its photoisomerization mechanism leveraged on the computational scrutiny with ever-increasing levels of theory. However, the most resolved absorption spectrum for the transition to S1(nπ*) has not followed the computational advances and is more than half a century old. Here, using jet-cooled molecular beam and multiphoton ionization techniques we report the first high-resolution spectra of S1(nπ*) and S2(ππ*). The photophysical characterization reveals directly the structural changes upon excitation and the timescales of dynamical processes. For S1(nπ*), we find that changes in the hybridization of the nitrogen atoms are the driving force that triggers isomerization. In combination with quantum chemical calculations we conclude that photoisomerization occurs along an inversion-assisted torsional pathway with a barrier of ~2 kcal mol(-1). This methodology can be extended to photoresponsive molecular systems so far deemed non-accessible to high-resolution spectroscopy. PMID:25562840

  8. Application of peptide nucleic acids containing azobenzene self-assembled electrochemical biosensors in detecting DNA sequences

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Hybridization of peptide nucleic acids probe containing azobenzene (NH2-TNT4, N-PNAs) with DNA was performed by covalently immobilizing of NH2-TNT4 in sequence on the 3-mercaptopropionic acid self-assembled monolayer modified gold electrode with the helps of N-(3-dimethylaminopropy1)-N’-ethylcarbodiimide hydrochloride (EDC) and N-hydroxysuccinimide (NHS), and the hybrid was coded as N-PNAs/DNA. Using [Fe(CN)6]4-/3- (1:1) as the electrochemical indicator, the electrochemical properties of the N-PNAs self-assembled monolayer (N-PNAs-SAMs) and N-PNAs/DNA hybridization system under the conditions of before and after UV light irradiation were characterized with cyclic voltammetry (CV), differential pulse voltammetry (DPV), and electrochemical impedance spectra (EIS). Results showed that the redox currents decreased with the increase of irradiation time, suggesting that the ability of the charge transfer on the electrode surface was weakened and the conformation of hybrid system had been changed, and the control of PNAs/DNA hybridization could be realized by UV light irradiation.

  9. Two-photon brightness of azobenzene photoswitches designed for glutamate receptor optogenetics.

    Science.gov (United States)

    Carroll, Elizabeth C; Berlin, Shai; Levitz, Joshua; Kienzler, Michael A; Yuan, Zhe; Madsen, Dorte; Larsen, Delmar S; Isacoff, Ehud Y

    2015-02-17

    Mammalian neurotransmitter-gated receptors can be conjugated to photoswitchable tethered ligands (PTLs) to enable photoactivation, or photoantagonism, while preserving normal function at neuronal synapses. "MAG" PTLs for ionotropic and metabotropic glutamate receptors (GluRs) are based on an azobenzene photoswitch that is optimally switched into the liganding state by blue or near-UV light, wavelengths that penetrate poorly into the brain. To facilitate deep-tissue photoactivation with near-infrared light, we measured the efficacy of two-photon (2P) excitation for two MAG molecules using nonlinear spectroscopy. Based on quantitative characterization, we find a recently designed second generation PTL, L-MAG0460, to have a favorable 2P absorbance peak at 850 nm, enabling efficient 2P activation of the GluK2 kainate receptor, LiGluR. We also achieve 2P photoactivation of a metabotropic receptor, LimGluR3, with a new mGluR-specific PTL, D-MAG0460. 2P photoswitching is efficiently achieved using digital holography to shape illumination over single somata of cultured neurons. Simultaneous Ca(2+)-imaging reports on 2P photoswitching in multiple cells with high temporal resolution. The combination of electrophysiology or Ca(2+) imaging with 2P activation by optical wavefront shaping should make second generation PTL-controlled receptors suitable for studies of intact neural circuits.

  10. Engineered Ionizable Side Chains.

    Science.gov (United States)

    Cymes, Gisela D; Grosman, Claudio

    2015-01-01

    One of the great challenges of mechanistic ion-channel biology is to obtain structural information from well-defined functional states. In the case of neurotransmitter-gated ion channels, the open-channel conformation is particularly elusive owing to its transient nature and brief mean lifetime. In this Chapter, we show how the analysis of single-channel currents recorded from mutants engineered to contain single ionizable side chains in the transmembrane region can provide specific information about the open-channel conformation without any interference from the closed or desensitized conformations. The method takes advantage of the fact that the alternate binding and unbinding of protons to and from an ionizable side chain causes the charge of the protein to fluctuate by 1 unit. We show that, in mutant muscle acetylcholine nicotinic receptors (AChRs), this fluctuating charge affects the rate of ion conduction in such a way that individual proton-transfer events can be identified in a most straightforward manner. From the extent to which the single-channel current amplitude is reduced every time a proton binds, we can learn about the proximity of the engineered side chain to the lumen of the pore. And from the kinetics of proton binding and unbinding, we can calculate the side-chain's affinity for protons (pK a), and hence, we can learn about the electrostatic properties of the microenvironment around the introduced ionizable group. The application of this method to systematically mutated AChRs allowed us to identify unambiguously the stripes of the M1, M2 and M3 transmembrane α-helices that face the pore's lumen in the open-channel conformation in the context of a native membrane. PMID:26381938

  11. Graphene Side Gate Engineering

    OpenAIRE

    Chen, Ching-Tzu; Low, Tony; Chiu, Hsin-Ying; Zhu, Wenjuan

    2014-01-01

    Various mesoscopic devices exploit electrostatic side gates for their operation. In this paper, we investigate how voltage-biasing of graphene side gates modulates the electrical transport characteristics of graphene channel. We explore myriads of typical side gated devices such as symmetric dual side gates and asymmetric single side gate biasing, in monolayer and bilayer graphene. The side gates modulate the electrostatic doping in the graphene channel whose effect is reflected in transport ...

  12. Azobenzene-derived tris-β-diketonate lanthanide complexes: reversible trans-to-cis photoisomerization in solution and solid state.

    Science.gov (United States)

    Lin, Li-Rong; Wang, Xuan; Wei, Gao-Ning; Tang, Hui-Hui; Zhang, Hui; Ma, Li-Hua

    2016-10-14

    Novel azobenzene-derived β-diketonates (4,4,5,5,6,6,6-heptafluoro-1-azobenzene-1,3-hexanedione (LA), 4,4,5,5,6,6,6-heptafluoro-1-(4-dimethylamino)azobenzene-1,3-hexanedione (LB)) were designed and their complexes with lanthanide cations (La(3+), Eu(3+), Gd(3+), Yb(3+)) were prepared and characterized by (1)H NMR, FT-IR, and elemental analysis. Three of the complexes were crystallized successfully and identified by X-ray diffraction. It was significant to find that LA showed remarkably reversible trans-to-cis isomerization properties, however, LB, bearing an electron donor compared with LA, slowed down the isomerization to an extent. The presence of Ln(iii) enhanced the reversible trans-to-cis isomerization properties of both LA and LB a little upon photoirradiation in organic solvents, and amazingly increased the fatigue resistance. In addition, the complexes doped in polymethyl methacrylate (PMMA) films produced a similar phenomenon as well as when in solution. Theoretical calculations based on time dependent density functional theory (TD-DFT) were performed for geometry optimization and to determine the excitation energies of LA and LB to gain further insight into the electronic structure of the complexes, and the data were consistent with the experimental results. The excellent reversible photoisomerization properties of the newly designed Ln(iii) complexes can offer important advantages that will help with the further study of these materials to reach their full potential in applications such as molecular switching devices.

  13. Covalent functionalization of graphene by azobenzene with molecular hydrogen bonds for long-term solar thermal storage

    OpenAIRE

    Feng, Yiyu; Liu, Hongpo; Luo, Wen; Liu, Enzuo; Zhao, Naiqin; Yoshino, Katsumi; Feng, Wei

    2013-01-01

    Reduced graphene oxide-azobenzene (RGO-AZO) hybrids were prepared via covalent functionalization for long-term solar thermal storage. Thermal barrier (ΔEa ) of cis to tran reversion and thermal storage (ΔH) were improved by molecular hydrogen bonds (H-bonds) through ortho- or para-substitution of AZO. Intramolecular H-bonds thermally stabilized cis-ortho-AZO on RGO with a long-term half-life of 5400 h (ΔEa = 1.2 eV), which was much longer than that of RGO-para-AZO (116 h). RGO-para-AZO with o...

  14. Azobenzene-aminoglycoside: Self-assembled smart amphiphilic nanostructures for drug delivery.

    Science.gov (United States)

    Deka, Smriti Rekha; Yadav, Santosh; Mahato, Manohar; Sharma, Ashwani Kumar

    2015-11-01

    Here, we have designed and synthesized a novel cationic amphiphilic stimuli-responsive azobenzene-aminoglycoside (a small molecule) conjugate, Azo-AG 5, and characterized it by UV and FTIR. Light responsive nature of Azo-AG 5 was assessed under UV-vis light. Self- assembly of Azo-AG 5 in aqueous solutions into nanostructures and their ability to act as drug carrier were also investigated. The nanostructures of Azo-AG 5 showed average hydrodynamic diameter of ∼ 255 nm with aminoglycoside moiety (neomycin) and 4-dimethylaminoazobenzene forming hydrophilic shell and hydrophobic core, respectively. In the hydrophobic core, eosin and aspirin were successfully encapsulated. Dynamic light scattering (DLS) measurements demonstrated that the nanoassemblies showed expansion and contraction on successive UV and visible light irradiations exhibiting reversible on-off switch for controlling the drug release behavior. Similar behavior was observed when these nanostructures were subjected to pH-change. In vitro drug release studies showed a difference in UV and visible light-mediated release pattern. It was observed that the release rate under UV irradiation was comparatively higher than that observed under visible light. Further, azoreductase-mediated cleavage of the azo moiety in Azo-AG 5 nanoassemblies resulted in the dismantling of the structures into aggregated microstructures. Azo-AG 5 nanostructures having positive surface charge (+9.74 mV) successfully interacted with pDNA and retarded its mobility on agarose gel. Stimuli responsiveness of nanostructures and their on-off switch like behavior ensure the great potential as controlled drug delivery systems and in other biomedical applications such as colon-specific delivery and gene delivery. PMID:26255160

  15. Highly Sensitive Thin-Film Field-Effect Transistor Sensor for Ammonia with the DPP-Bithiophene Conjugated Polymer Entailing Thermally Cleavable tert-Butoxy Groups in the Side Chains.

    Science.gov (United States)

    Yang, Yang; Zhang, Guanxin; Luo, Hewei; Yao, Jingjing; Liu, Zitong; Zhang, Deqing

    2016-02-17

    The sensing and detection of ammonia have received increasing attention in recent years because of the growing emphasis on environmental and health issues. In this paper, we report a thin-film field-effect transistor (FET)-based sensor for ammonia and other amines with remarkable high sensitivity and satisfactory selectivity by employing the DPP-bithiophene conjugated polymer pDPPBu-BT in which tert-butoxycarboxyl groups are incorporated in the side chains. This polymer thin film shows p-type semiconducting property. On the basis of TGA and FT-IR analysis, tert-butoxycarboxyl groups can be transformed into the -COOH ones by eliminating gaseous isobutylene after thermal annealing of pDPPBu-BT thin film at 240 °C. The FET with the thermally treated thin film of pDPPBu-BT displays remarkably sensitive and selective response toward ammonia and volatile amines. This can be attributed to the fact that the elimination of gaseous isobutylene accompanies the formation of nanopores with the thin film, which will facilitate the diffusion and interaction of ammonia and other amines with the semiconducting layer, leading to high sensitivity and fast response for this FET sensor. This FET sensor can detect ammonia down to 10 ppb and the interferences from other volatile analytes except amines can be negligible. PMID:26883723

  16. Through-space (19)F-(19)F spin-spin coupling in ortho-fluoro Z-azobenzene.

    Science.gov (United States)

    Rastogi, Shiva K; Rogers, Robert A; Shi, Justin; Brown, Christopher T; Salinas, Cindy; Martin, Katherine M; Armitage, Jacob; Dorsey, Christopher; Chun, Gao; Rinaldi, Peter; Brittain, William J

    2016-02-01

    We report through-space (TS) (19)F-(19)F coupling for ortho-fluoro-substituted Z-azobenzenes. The magnitude of the TS-coupling constant ((TS) JFF ) ranged from 2.2-5.9 Hz. Using empirical formulas reported in the literature, these coupling constants correspond to non-bonded F-F distances (dFF) of 3.0-3.5 Å. These non-bonded distances are significantly smaller than those determined by X-ray crystallography or density functional theory, which argues that simple models of (19)F-(19)F TS spin-spin coupling solely based dFF are not applicable. (1)H, (13)C and (19)F data are reported for both the E and Z isomers of ten fluorinated azobenzenes. Density functional theory [B3YLP/6-311++G(d,p)] was used to calculate (19) F chemical shifts, and the calculated values deviated 0.3-10.0 ppm compared with experimental values.

  17. Dethreading of a Photoactive Azobenzene-Containing Molecular Axle from a Crown Ether Ring: A Computational Investigation.

    Science.gov (United States)

    Tabacchi, Gloria; Silvi, Serena; Venturi, Margherita; Credi, Alberto; Fois, Ettore

    2016-06-17

    Pseudorotaxanes formed by a dibenzo[24]crown-8 ring (R) and a dialkylammonium axle bearing either two E- or two Z-azobenzene units (EE-A or ZZ-A) revealed useful for the construction of light-powered molecular machines and motors, as they provide the opportunity of photocontrolling self-assembly/disassembly processes. The potential energies profiles for the dethreading of these complexes have been investigated by adopting a combination of first-principles molecular dynamics, metadynamics and quantum-chemical geometry optimization approaches. While the dethreading of the EE-A axle is associated with a monotonic energy increase, for that of the ZZ-A axle a transition state and an intermediate structure, in which the components are still threaded together, are found. The rate determining step for the dethreading of the ZZ axle has a higher energy barrier than that of the EE axle, in agreement with the experimental kinetic data. Moreover, the results suggest that the elliptic shape of the ring cavity is important for discriminating between the E and Z terminal azobenzene during dethreading.

  18. Properties of mixed-crystalline organic material prepared by zone levelling IV. Melting properties and excess enthalpies of (trans-azobenzene + trans-stilbene)

    NARCIS (Netherlands)

    Bouwstra, J.A.; Leeuw, V.V. de; Miltenburg, J.C.

    1985-01-01

    Homogeneous mixed crystals of (trans-azobenzene + trans-stilbene) were prepared. Molar heat capacities of the pure substances and the mixed crystals were determined at temperatures from 300 to 400 K. The melting temperatures and molar enthalpies of fusion were measured for trans-stilbene and trans-a

  19. Putting the Side first

    Energy Technology Data Exchange (ETDEWEB)

    1994-02-01

    SIDE Minerals is a relative newcomer to the South African mining industry. It combines coal and anthracite mining and has base and precious metal interests. Side Minerals has offices in Boksburg from where its mining operations in Delmas, Witbank and Carolina in the Eastern Transvaal, and Newcastle in Natal are controlled. Lakeside Colliery at Witbank -a mine with a life expectancy of 15 years - is both an underground and opencast operation with an annual production capacity of 1,2 Mt of high, medium and low grade coal. Opencast extraction there is by the strip mining method. This is done on contract by Concor Mining Opencast Division, a member of the Concor Holding Group. A high wall face provides entry to the underground operations. Eastside Colliery at Carolina, which has the capacity to produce 480 000 tons of coal a year, is currently an opencast operation with underground mining scheduled to begin during 1994. Westside Colliery near Delmas is on a care and maintenance basis, but it has the capacity to produce 600 000 tons of low grade phosphorous coal which is required by the ferro-alloy and steel industries. 2 figs.

  20. Preparation and Properties of Novel Polyimide Film with Maleimide Side Groups%马来酰亚胺侧基聚酰亚胺薄膜的制备与性能研究

    Institute of Scientific and Technical Information of China (English)

    虞鑫海; 许梅芳; 樊良子; 徐永芬; 陈武荣; 李立严

    2011-01-01

    利用2,2-双[4-(2,4-二氨基苯氧基)苯基]丙烷(BDAPPP)单体、马来酸酐(MA)、4,4’-二氨基二苯醚( 44ODA)及3,3’,4,4’-四羧酸联苯二酐(BPDA)合成制得马来酰胺酸侧基的聚酰胺酸树脂(MPAA)溶液,经涂膜,热亚胺化,得到坚韧透明的马来酰亚胺侧基聚酰亚胺薄膜(MPI),并对其性能进行研究.结果表明:马来酰亚胺侧基聚酰亚胺薄膜(MPI)具有较低的表面能(34.4 mJ/m2)、较低的吸水率(0.12%)以及良好的紫外吸收性能和较高的可见光透过性(88%),且具有良好的电容、介电损耗稳定性,几乎不受工作频率的影响,对其在高低频环境下的应用非常有利.%Based on the monomers of 2, 2-bis[4-(2, 4-diaminophenoxy) phenyl] propane(BDAPPP), maleic anhydride (MA), 4, 4'-diaminodiphenyl ether(44ODA) and 3, 3', 4, 4'-tetracarboxylbiphenyl di-anhydride(BPDA), a novel polyamic acid solution with maleimide side groups(MPAA) was synthesized. The transparent and tenacious polyimide film with maleimide side groups (MPI) was prepared through imidized process of the MPAA thin layer, and then the properties of the MPI were studied. The results show that the MPI has low surface energy(34.4 mJ/ m2), low water absorption (0.12%), good ultraviolent absorbability, high visible light transparency, and excellent stability of capacitance and dielectric loss within a wide frequency range of 100 kHz~1 MHz.

  1. 'Side-by-side'

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    2010-07-01

    France is a nuclear power nation. And this is not going to change. However, at the same time, the country is also pursuing massive investments in the expansion of renewable energies. According to France's President Nicolas Sarkozy, the motto should be: 'side-by-side' rather than 'one or the other'. For the PV sector, whose success was unbroken during the crisis in 2009, the signal is positive and could mean sustained growth. (orig.)

  2. Side Effects (Management)

    Science.gov (United States)

    ... cancer care is relieving side effects, called symptom management, palliative care, or supportive care. It is important ... treat them. To learn about the symptoms and management of the long-term side effects of cancer ...

  3. Catalytic transfer hydrogenation of azobenzene by low-valent nickel complexes: a route to 1,2-disubstituted benzimidazoles and 2,4,5-trisubstituted imidazolines.

    Science.gov (United States)

    Zurita, Daniel A; Flores-Alamo, Marcos; García, Juventino J

    2016-06-21

    The one-pot synthesis of 1,2-disubstituted benzimidazoles by the transfer hydrogenation of azobenzene, using benzylamine as a hydrogen donor, sequential rearrangement of hydrazobenzene to semidine and further condensation with N-benzylideneamine is reported, catalyzed by 2 mol% of [Ni(COD)2] : dippe. The N2 substitution on benzimidazole can be controlled by the selection of different azobenzenes and C2 substitution will only depend on the chosen benzylamine. The current methodology avoids the addition of external oxidants, which are needed in the classical benzimidazole synthesis. In addition, the byproduct, N-benzylideneamine, obtained from dehydrogenation of benzylamine produced 2,4,5-trisubstituted imidazolines by cyclization and C-H functionalization, and this route was optimized with the use of 2 mol% of [Ni(COD)2] : 2PPh3. PMID:27254530

  4. One-sided arguments

    NARCIS (Netherlands)

    van Laar, J.A.

    2007-01-01

    When is an argument to be called one-sided? When is putting forward such an argument fallacious? How can we develop a model for critical discussion, such that a fallaciously one-sided argument corresponds to a violation of a discussion rule? These issues are dealt with within 'the limits of the dial

  5. A New Biindenylidenedione Compound with Two Azobenzene Units:Synthesis and Photochromic Behavior Both in Solution and in the Solid State

    Institute of Scientific and Technical Information of China (English)

    LIU Juyan; HAN Jie; WANG Juanyu; PANG Meili; MENG Jiben

    2009-01-01

    A new photochromic biindenylidenedione compound bearing two azobenzene units was synthesized and characterized by means of 1H NMR,13C NMR,ESI-MS and elemental analysis.The photochromic and photo-induced radical properties were investigated by means of UV-Vis and electron spin resonance spectroscopy,respectively.The results showed that the title compound exhibited photochromic behavior with good fatigue resistances both in solution and in the solid state.

  6. 石墨烯/偶氮杂化材料研究进展%Progress on graphene/azobenzene hybrid materials

    Institute of Scientific and Technical Information of China (English)

    王东瑞; 王晓工

    2012-01-01

    Graphene, a true two dimensional nanomaterial with the layer thickness of one atom, has showed many outstanding properties and aroused tremendous research enthusiasm. Azobenzene-containing polymers and other materials have also attracted considerable attention because of the unique photoresponsive properties. Graphene/ azobenzene hybrids materials can combine interesting properties of graphere and azobenzene-containing materials and have been studied in authors and other laboratories in recent years. This review highlighted some recent research progresses in this area. The content of this article included the preparations of graphene/azobenzene hybrids materials through surface-grafting of azo polymers, covalent-bonding modification with low-molecular-weight azo compounds and electrostatic layer-by-layer deposition. The photoresponsive properties and application in the electronchemical energy storage device of the materials were also reviewed in some detail.%石墨烯作为一种新型二维平面纳米材料,表现出许多优异的物理性质.含偶氮苯的化合物和聚合物作为功能材料具有独特的光响应性质.将石墨烯的特性与偶氮材料的光响应性相结合,有望发展一类具有卓越性能的新型光电功能材料.本文总结了石墨烯/偶氮杂化材料这一研究方向的最新进展,重点介绍了杂化材料的制备、表征和光电功能性质等,并简要展望了这类材料的发展前景.

  7. Peptide nanotube aligning side chains onto one side.

    Science.gov (United States)

    Tabata, Yuki; Mitani, Shota; Kimura, Shunsaku

    2016-06-01

    A novel pseudo cyclic penta-β-peptide composed of a β-naphthylalanine, two β-alanines, and a sequence of ethylenediamine-succinic acid (CP5ES) is synthesized and investigated on peptide nanotube (PNT) formation. When the PNT is formed with the maximum number of intermolecular hydrogen bonds between the cyclic peptides, the sequence enables the alignment of the side chains, naphthyl groups, on one side of the PNT. Microscopic and spectroscopic observations of CP5ES crystals reveal that CP5ES forms rod- or needle-shaped molecular assemblies showing exciton coupling of the Cotton effect and predominant monomer emission, which are different from a reference cyclic tri-β-peptide composed of a β-naphthylalanine and two β-alanines. Insertion of a sequence of ethylenediamine-succinic acid into β-amino acids in the cyclic skeleton is therefore suggested to be effective to make the side chains aligning on one side of the PNT. Copyright © 2016 European Peptide Society and John Wiley & Sons, Ltd. PMID:27282135

  8. Side-wall sampler

    Energy Technology Data Exchange (ETDEWEB)

    Morrison, B.

    1969-11-01

    A side-wall sampler which is capable of taking samples from the walls of test holes to a depth of 1,000 ft or more is described. Samples have been extracted from till, clay, silt, and fine- to coarse-grained sands in drift and nonindurated bedrock from more than 1,000 test holes in S. Saskatchewan. Side-hole sampling is faster and cheaper than conventional sampling methods and is ideally suited for geological investigations. Mineralogical paleonto- locical and radiocarbon analyses have been determined on side-hole cores.

  9. Late side effects of short-course preoperative radiotherapy combined with total mesorectal excision for rectal cancer : Increased bowel dysfunction in irradiated patients - A dutch colorectal cancer group study

    NARCIS (Netherlands)

    Peeters, KCMJ; van de Velde, CJH; Leer, JWH; Martijn, H; Junggeburt, JMC; Kranenbarg, EK; Steup, WH; Wiggers, T; Rutten, HJ; Marijnen, CAM

    2005-01-01

    Purpose Preoperative short-term radiotherapy improves local control in patients treated with total mesorectal excision (TME). This study was performed to assess the presence and magnitude of long-term side effects of preoperative 5 x 5 Gy radiotherapy and TME. Also, hospital treatment was recorded f

  10. Late side effects of short-course preoperative radiotherapy combined with total mesorectal excision for rectal cancer: increased bowel dysfunction in irradiated patients--a Dutch colorectal cancer group study.

    NARCIS (Netherlands)

    Peeters, K.C.; Velde, C.J. van de; Leer, J.W.H.; Martijn, H.; Junggeburt, J.M.; Kranenbarg, E.K.; Steup, W.H.; Wiggers, T.; Rutten, H.J.; Marijnen, C.A.M.

    2005-01-01

    PURPOSE: Preoperative short-term radiotherapy improves local control in patients treated with total mesorectal excision (TME). This study was performed to assess the presence and magnitude of long-term side effects of preoperative 5 x 5 Gy radiotherapy and TME. Also, hospital treatment was recorded

  11. Side Payments in Marketing

    OpenAIRE

    John R. Hauser; Duncan I. Simester; Birger Wernerfelt

    1997-01-01

    Side payments, known politely as gainsharing and pejoratively as bribery, are prevalent in marketing. Indeed, many management schools have added ethics modules to their basic marketing courses to discuss these issues and there is much discussion of side payments in the literature (e.g., Adams 1995, Borrus [Borrus, Amy. 1995. A world of greased palms. (November 6) 36–38.], Mauro [Mauro, Paolo. 1997. Why worry about corruption? . Washington, D.C.], Mohl [Mohl, Bruce. 1996. Auto dealers color su...

  12. [Psychoanalysis and Side Effect].

    Science.gov (United States)

    Shirahase, Joichiro

    2015-01-01

    A study of psychoanalysis from the perspective of side effects reveals that its history was a succession of measures to deal with its own side effects. This, however, does not merely suggest that, as a treatment method, psychoanalysis is incomplete and weak: rather, its history is a record of the growth and development of psychoanalysis that discovered therapeutic significance from phenomena that were initially regarded as side effects, made use of these discoveries, and elaborated them as a treatment method. The approach of research seen during the course of these developments is linked to the basic therapeutic approach of psychoanalysis. A therapist therefore does not draw conclusions about a patient's words and behaviors from a single aspect, but continues to make efforts to actively discover a variety of meanings and values from them, and to make the patient's life richer and more productive. This therapeutic approach is undoubtedly one of the unique aspects of psychoanalysis. I discuss the issue of psychoanalysis and side effects with the aim of clarifying this unique characteristic of psychoanalysis. The phenomenon called resistance inevitably emerges during the process of psychoanalytic treatment. Resistance can not only obstruct the progress of therapy; it also carries the risk of causing a variety of disadvantages to the patient. It can therefore be seen as an adverse effect. However, if we re-examine this phenomenon from the perspective of transference, we find that resistance is in fact a crucial tool in psychoanalysis, and included in its main effect, rather than a side effect. From the perspective of minimizing the character of resistance as a side effect and maximizing its character as a main effect, I have reviewed logical organization, dynamic evaluation, the structuring of treatment, the therapist's attitudes, and the training of therapists. I conclude by stating that psychoanalysis has aspects that do not match the perspective known as a side

  13. Effect of knee joint angle on side-to-side strength ratios.

    Science.gov (United States)

    Krishnan, Chandramouli; Williams, Glenn N

    2014-10-01

    Isometric knee extensor and flexor strength are typically tested at different joint angles due to the differences in length-tension relationships of the quadriceps and hamstring muscles. The efficiency of strength testing can be improved if the same angle can be used to test both the knee extensor and flexor muscle groups. The aim of this study was to determine an optimal angle for isometric knee strength testing by examining the effect of knee angle on side-to-side peak torque ratios. Eighteen active young people (9 males and 9 females) participated in this study. Knee extensor and knee flexor strength were tested on both sides at 30°, 60°, and 90° of knee flexion. The effect of knee flexion angle on side-to-side peak torque ratios, raw torque values, and side-to-side flexor-to-extensor torque ratios were assessed. Side-to-side knee extensor peak torque ratios and knee flexor-to-extensor torque ratios differed significantly by knee flexion angle (p = 0.024 and p = 0.011, respectively), but side-to-side knee flexor peak torque ratios did not differ significantly (p = 0.311). When considering both side-to-side peak torque ratios and flexor-to-extensor torque ratios, the values were more symmetrical (i.e., closer to 100%) only at 60° of knee flexion. Our results indicate that both the knee flexors and the knee extensors can be tested clinically at 60° of knee flexion. Our results also indicate that the hamstrings can be tested at any of the 3 angles if the examiner is interested in side-to-side ratios rather than raw torque values. These results may facilitate more efficient and flexible clinical knee strength testing.

  14. Synthesis, optical and thermal behaviour of palladium(II) complexes with 4-(4-alkoxy-2-hydroxybenzylideneamino)azobenzene

    Indian Academy of Sciences (India)

    Boon-Teck Heng; Guan-Yeow Yeap; Daisuke Takeuchi

    2013-11-01

    A series of new Pd(II) complexes derived from the reaction of palladium acetate with 4-(4-alkoxy-2-hydroxybenzylideneamino)azobenzene having the flexible terminal chain of OCH2+1, in which n are even numbers ranging from 8 to 16, has been successfully synthesized. The physical measurement and spectroscopic techniques (FTIR and 1H-NMR) reveal that the Pd(II) complexes possess the Pd-N and Pd-O coordination modes in which the central Pd(II) adopts square-planar geometry. The observation under the polarized light shows that all the ligands and Pd(II) complexes exhibit enantiotropic mesophases. The ligands with -octyloxy and -decyloxy flexible chains exhibit the nematic (N) and smectic A (SmA) phases whilst the Pd(II) complexes show exclusive SmA phase. The SmA phase observed in Pd(II) complexes can be supported by the presence of focal conic fan-shaped texture with the presence of curved lines which are prominent during the cooling process. On the other hand, the comparison studies show that Pd(II) complexes possess exceptional higher phase transition temperatures as compared to the corresponding Cu(II) and Ni(II) complexes.

  15. Reversible switching in self-assembled monolayers of azobenzene thiolates on Au (111) probed by threshold photoemission

    International Nuclear Information System (INIS)

    Highlights: ► Photoelectron spectroscopy of liquid phase prepared SAMs of azobenzene derivative. ► Photo-induced reversible switching in densely packed SAM is monitored. ► Maximum density of switched molecules in SAM is derived from photoemission data. ► Switching reaction only enabled at defects sites within the molecular layer. - Abstract: The reversible photo- and thermally activated isomerization of the molecular switch 3-(4-(4-Hexyl-phenylazo)-phenoxy)-propane-1-thiol (ABT, short for AzoBenzeneThiol) deposited by self-assembly from solution on Au (111) was studied using laser-based photoelectron spectroscopy. Differences in the molecular dipole moment characteristic for the trans and the cis isomer of ABT were monitored via changes in the sample work function, accessible by detection of the threshold energy for photoemission. A quantitative analysis of our data shows that the fraction of molecules within the densely packed monolayer that undergoes a switching process is of the order of 1%. This result indicates the relevance of substrate and film defects required to overcome the steric or electronic hindrance of the isomerization reaction in a densely packed monolayer.

  16. Assessing computationally efficient isomerization dynamics: Delta-SCF density-functional theory study of azobenzene molecular switching

    CERN Document Server

    Maurer, Reinhard J; 10.1063/1.3664305

    2012-01-01

    We present a detailed comparison of the S0, S1 (n -> \\pi*) and S2 (\\pi -> \\pi*) potential energy surfaces (PESs) of the prototypical molecular switch azobenzene as obtained by Delta-self-consistent-field (Delta-SCF) Density-Functional Theory (DFT), time-dependent DFT (TD-DFT) and approximate Coupled Cluster Singles and Doubles (RI-CC2). All three methods unanimously agree in terms of the PES topologies, which are furthermore fully consistent with existing experimental data concerning the photo-isomerization mechanism. In particular, sum-method corrected Delta-SCF and TD-DFT yield very similar results for S1 and S2, when based on the same ground-state exchange-correlation (xc) functional. While these techniques yield the correct PES topology already on the level of semi-local xc functionals, reliable absolute excitation energies as compared to RI-CC2 or experiment require an xc treatment on the level of long-range corrected hybrids. Nevertheless, particularly the robustness of Delta-SCF with respect to state c...

  17. Working the Dark Side

    DEFF Research Database (Denmark)

    Bjering, Jens Christian Borrebye

    half—dark side—documents the making and nature of the dark side by analyzing a series of legal memos from the Department of Justice's Office of Legal Council and from the White House and concludes by relating its findings to traditional ideas about emergency action, national security, and torture....... By analyzing official reports and testimonies from soldiers partaking in the War On Terror, the dissertation's second part—dark arts—focuses on the transformation of the dark side into a productive space in which “information” and the hunt for said information overshadowed all legal, ethical, or political...

  18. Computer-mediated communication as a channel for social resistance : The strategic side of SIDE

    NARCIS (Netherlands)

    Spears, R; Lea, M; Corneliussen, RA; Postmes, T; Ter Haar, W

    2002-01-01

    In two studies, the authors tested predictions derived from the social identity model of deindividuation effects (SIDE) concerning the potential of computer-mediated communication (CMC) to serve as a means to resist powerful out-groups. Earlier research using the SIDE model indicates that the anonym

  19. Nonprescription ibuprofen: side effect profile.

    Science.gov (United States)

    Furey, S A; Waksman, J A; Dash, B H

    1992-01-01

    Single doses of nonprescription analgesics are commonly used to treat self-diagnosed conditions. To evaluate the safety of single doses of nonprescription-strength ibuprofen, we examined reported side effects from 15 double-blind, randomized, controlled trials we conducted of the drug to treat various common painful conditions (e.g., headache, sore throat). All studies included placebo and another nonprescription analgesic, acetaminophen. A total of 878 subjects received ibuprofen 200 or 400 mg, 849 acetaminophen 650 or 1000 mg, and 852 placebo. The overall frequency of side effects was comparable: ibuprofen 2.4%, acetaminophen 3.2%, and placebo 2.1%. The frequency of central nervous system symptoms was 0.8%, 2.1%, and 0.9%, respectively. Upper gastro-intestinal upset ranged from 0.8-0.9% of subjects in all groups. We conclude that single doses of nonprescription ibuprofen are well tolerated and demonstrate a side effect profile indistinguishable from that of acetaminophen and placebo. PMID:1437701

  20. Colorectal cancers choosing sides

    NARCIS (Netherlands)

    Albuquerque, Cristina; Bakker, Elvira R. M.; van Veelen, Wendy; Smits, Ron

    2011-01-01

    In contrast to the majority of sporadic colorectal cancer which predominantly occur in the distal colon, most mismatch repair deficient tumours arise at the proximal side. At present, these regional preferences have not been explained properly. Recently, we have screened colorectal tumours for mutat

  1. Side effects of ergotamine

    NARCIS (Netherlands)

    Meyler, WJ

    1996-01-01

    Ergotamine has been used for many years in the treatment of migraine, although there is Little formal clinical evidence that it is significantly more efficacious than placebo. A number of side effects associated with ergotamine have been reported in the literature, including myocardial infarction, i

  2. The Two Sides of Money Laundering

    OpenAIRE

    Corina – Maria ENE

    2014-01-01

    The mainly goal of money laundering is to carry out more and more illegal economic transactions or activities to produce individual or groups gains and then to legitimate them. Money laundering converts illicit source of money generated by criminal activities in order to hide the connection between money and their original illegal activities. This is one of money laundering side. The second side implies corruption. While money laundering is a passing channel for illicit funds due to its crimi...

  3. Right- and Left-Handed Helices, What is in between? Interconversion of Helical Structures of Alternating Pyridinedicarboxamide/m-(phenylazo)azobenzene Oligomers.

    Science.gov (United States)

    Tao, Peng; Parquette, Jon R; Hadad, Christopher M

    2012-12-11

    Some unnatural polymers/oligomers have been designed to adopt a well-defined, compact, three-dimensional folding capability. Azobenzene units are common linkages in these oligomer designs. Two alternating pyridinedicarboxamide/m-(phenylazo)azobenzene oligomers that can fold into both right- and left-handed helices were studied computationally in order to understand their dynamical properties. Helical structures were shown to be the global minima among the many different conformations generated from the Monte Carlo simulations, and extended conformations have higher potential energies than compact ones. To understand the interconversion process between right- and left-handed helices, replica-exchange molecular dynamic (REMD) simulations were performed on both oligomers, and with this method, both right- and left-handed helices were successfully sampled during the simulations. REMD trajectories revealed twisted conformations as intermediate structures in the interconversion pathway between the two helical forms of these azobenzene oligomers. This mechanism was observed in both oligomers in current study and occurred locally in the larger oligomer. This discovery indicates that the interconversion between helical structures with different handedness goes through a compact and partially folded structure instead of globally unfold and extended structure. This is also verified by the nudged elastic band (NEB) calculations. The temperature weighted histogram analysis method (T-WHAM) was applied on the REMD results to generate contour maps of the potential of mean force (PMF). Analysis showed that right- and left-handed helices are equally sampled in these REMD simulations. In large oligomers, both right- and left-handed helices can be adopted by different parts of the molecule simultaneously. The interconversion between two helical forms can occur in the middle of the helical structure and not necessarily at the termini of the oligomer.

  4. Pen-side testing

    International Nuclear Information System (INIS)

    Pen-side diagnostic testing is often required to provide real time information about the health status of an animal or herd. The rapid results are generally needed in the face of a disease outbreak where the diagnostician/clinician is presented with dead or dying animals. Another use of pen-side tests is as part of a preventive medicine/herd health programme, where the information can be used for determining pathogen incidence and prevalence in the herd, identifying potential carrier animals or evaluating subtle changes in overall herd health as a result of management changes. Still another area is as a part of health certification before sale or stocking, or during processing following slaughter. Advanced testing methods, which in the past were only appropriate for use in a laboratory setting, have now been formatted for use in the field. Enzyme immunoassays (EIAs) and immunochromatorgraphy have greatly enhanced diagnostic pen-side capabilities. These test systems allow for the rapid, sensitive and specific detection of target antigen or antibody and require little or no scientific equipment. Because of the wide format flexibility these immunochemical technologies allow, they have come to dominate the diagnostic industry, both in the laboratory and in the field. Using liquid phase or precipitating chromogens, the tests can be visually interpreted and do not need instrumentation. Immunochromatography, a simplified assay system, has found widespread application as a field or pen-side test. The entire assay takes only one or two steps, and the results appear within 5-10 minutes. In the future, DNA based diagnostics will become more adaptable for use in the field. The DNA hybridization systems are at present cumbersome and require elevated temperatures. Companies are currently working to develop fast formulas that provide results in less than an hour, have a limited number of steps and can be performed at lower temperatures. (author)

  5. Azobenzene mesogens mediated preparation of SnS nanocrystals encapsulated with in-situ N-doped carbon and their enhanced electrochemical performance for lithium ion batteries application

    Science.gov (United States)

    Wang, Meng; Zhou, Yang; Duan, Junfei; Chen, Dongzhong

    2016-09-01

    In this work, azobenzene mesogen-containing tin thiolates have been synthesized, which possess ordered lamellar structures persistent to higher temperature and serve as liquid crystalline precursors. Based on the preorganized tin thiolate precursors, SnS nanocrystals encapsulated with in-situ N-doped carbon layer have been achieved through a simple solventless pyrolysis process with the azobenzene mesogenic thiolate precursor served as Sn, S, N, and C sources simultaneously. Thus prepared nanocomposite materials as anode of lithium ion batteries present a large specific capacity of 604.6 mAh·g-1 at a current density of 100 mA·g-1, keeping a high capacity retention up to 96% after 80 cycles, and display high rate capability due to the synergistic effect of well-dispersed SnS nanocrystals and N-doped carbon layer. Such encouraging results shed a light on the controlled preparation of advanced nanocomposites based on liquid crystalline metallomesogen precursors and may boost their novel intriguing applications. Project supported by the National Natural Science Foundation of China (Grant No. 21574062) and the Huaian High-Technology Research Institute of Nanjing University, China (Grant No. 2011Q1).

  6. Azobenzene mesogens mediated preparation of SnS nanocrystals encapsulated with in-situ N-doped carbon and their enhanced electrochemical performance for lithium ion batteries application

    Science.gov (United States)

    Wang, Meng; Zhou, Yang; Duan, Junfei; Chen, Dongzhong

    2016-09-01

    In this work, azobenzene mesogen-containing tin thiolates have been synthesized, which possess ordered lamellar structures persistent to higher temperature and serve as liquid crystalline precursors. Based on the preorganized tin thiolate precursors, SnS nanocrystals encapsulated with in-situ N-doped carbon layer have been achieved through a simple solventless pyrolysis process with the azobenzene mesogenic thiolate precursor served as Sn, S, N, and C sources simultaneously. Thus prepared nanocomposite materials as anode of lithium ion batteries present a large specific capacity of 604.6 mAh·g‑1 at a current density of 100 mA·g‑1, keeping a high capacity retention up to 96% after 80 cycles, and display high rate capability due to the synergistic effect of well-dispersed SnS nanocrystals and N-doped carbon layer. Such encouraging results shed a light on the controlled preparation of advanced nanocomposites based on liquid crystalline metallomesogen precursors and may boost their novel intriguing applications. Project supported by the National Natural Science Foundation of China (Grant No. 21574062) and the Huaian High-Technology Research Institute of Nanjing University, China (Grant No. 2011Q1).

  7. 偶氮苯聚氨酯基抗皱功能高分子染料制备及性能%Synthesis and properties of azobenzene-polyurethane based anti-wrinkle polymeric dye

    Institute of Scientific and Technical Information of China (English)

    冒海燕; 张淼; 强思雨; 杨小祥; 王潮霞; 殷允杰

    2016-01-01

    为同步实现纺织品着色与功能整理并改善低分子染料的耐热迁移性,通过共价键合方式将N, N-二羟乙基偶氮苯发色体引入聚氨酯分子链,制备具有抗皱功能的偶氮苯聚氨酯基高分子染料.结果表明,偶氮苯发色体的反应率为87.81%,占聚氨酯链的3.53%,偶氮苯聚氨酯基高分子染料色光未发生变化,且涂层织物色泽鲜艳饱满,K/S值从1.50提高到4.61,急弹折皱回复角从110º增加到183º,缓弹折皱回复角从136º提高到227º,且热迁移率下降至5%,因此,偶氮苯聚氨酯基高分子染料不仅具有良好的抗皱性及耐热迁移性,而且为缩短纺织品生产工艺流程提供了一条新途径.%Azobenzene-polyurethane based polymeric dye with anti-wrinkle property was prepared by covalently bonding N,N-di(2-hydroxyethyl) azobenzene with polyurethane chain to synchronously realize coloring and functional finishing and enhance the thermal migration. Results showed that reaction rate of azobenzene and its content in polyurethane chain were 87. 81% and 3. 53%, respectively. The color remained unchanged after the azobenzene was introduced into polyurethane. The coated cotton fabric with the azobenzene-polyurethane polymeric dye presented more vivid and richer shade than that with azobenzene physically mixed polyurethane, and the K/S value increased from 1. 50 to 4. 61. The fast and delayed elastic recovery angles of the coated fabric were improved from 110 º to 183 º and 136 º to 227 º , respectively. The thermal migration rate was dramatically reduced to 5%. Consequently, the azobenzene-polyurethane polymeric dye exhibited outstanding anti-wrinkle property and thermal migration property, which provided a novel route for shortening the textile technological process.

  8. Probiotics: Safety and Side Effects

    Science.gov (United States)

    ... of this page please turn JavaScript on. Feature: Probiotics Safety and Side Effects Past Issues / Winter 2016 ... Says About the Safety and Side Effects of Probiotics Whether probiotics are likely to be safe for ...

  9. Side Chain Engineering in Solution-Processable Conjugated Polymers

    KAUST Repository

    Mei, Jianguo

    2014-01-14

    Side chains in conjugated polymers have been primarily utilized as solubilizing groups. However, these side chains have roles that are far beyond. We advocate using side chain engineering to tune a polymer\\'s physical properties, including absorption, emission, energy level, molecular packing, and charge transport. To date, numerous flexible substituents suitable for constructing side chains have been reported. In this Perspective article, we advocate that the side chain engineering approach can advance better designs for next-generation conjugated polymers. © 2013 American Chemical Society.

  10. HIV Medicines and Side Effects

    Science.gov (United States)

    Side Effects of HIV Medicines HIV Medicines and Side Effects (Last updated 1/7/2016; last reviewed 1/7/2016) Key Points HIV medicines help people with ... will depend on a person’s individual needs. Can HIV medicines cause side effects? HIV medicines help people ...

  11. Reversible light-controlled conductance switching of azobenzene-based metal/polymer nanocomposites

    International Nuclear Information System (INIS)

    We present a new concept of light-controlled conductance switching based on metal/polymer nanocomposites with dissolved chromophores that do not have intrinsic current switching ability. Photoswitchable metal/PMMA nanocomposites were prepared by physical vapor deposition of Au and Pt clusters, respectively, onto spin-coated thin poly(methylmethacrylate) films doped with azo-dye molecules. High dye concentrations were achieved by functionalizing the azo groups with tails and branches, thus enhancing solubility. The composites show completely reversible optical switching of the absorption bands upon alternating irradiation with UV and blue light. We also demonstrate reversible light-controlled conductance switching. This is attributed to changes in the metal cluster separation upon isomerization based on model experiments where analogous conductance changes were induced by swelling of the composite films in organic vapors and by tensile stress.

  12. Evolutionary side-steps

    NARCIS (Netherlands)

    Sluys, Ronald

    1992-01-01

    Many of the lower metazoans reach adulthood via complex developmental stages. Each of these stages is described with a specialized terminology, which is different for every major group of organisms. Biologists with a proper training in biodiversity may have learned about these complex issues during

  13. SYNTHESIS AND CHARACTERIZATION OF BIODEGRADABLES POLYURETHANE CONTAINING LIGHT SENSITIVE SIDE GROUPS%侧链为光敏感基团的可生物降解聚氨酯的合成及表征

    Institute of Scientific and Technical Information of China (English)

    杨立新; 王亮燕; 谢志刚; 胡秀丽; 黄宇彬; 景遐斌

    2013-01-01

    设计合成2-甲基-2-肉桂酰氧甲基-1,3-丙二醇(MCO)作为扩链剂,并以聚乳酸二醇(PLA diol)为软段,异佛尔酮二异氰酸酯(IPDI)和MCO为硬段制备了一系列侧链含有肉桂基团的可生物降解聚氨酯,结果表明MCO具有较高的反应活性,可满足制备高分子量聚氨酯的要求.聚氨酯结构中的肉桂双键可在紫外光和光引发剂的共同作用下,发生快速的交联反应,短时间内形成交联结构.软段结构相同时,凝胶含量随MCO含量的增加而增加.硬段结构相同时,凝胶含量随软段分子量的增加而减少.适度的交联可提高拉伸强度和形变回复率.%2-Methyl-2-cinnamoyloxymethyl-1, 3-propanediol ( MCO ) as a chain extender was prepared. Polylactide diol ( PLA diol) as soft segment, isophorone diisocyanate (IPDI) and MCO as hard segment were used to synthesize biodegradable polyurethane ( PU) containing light sensitive groups. The properties of the PUs obtained were characterized by nuclear magnetic resonance hydrogen spectrum ( 1H-NMR ) , Fourier transform infrared spectroscopy ( FTIR ) , gel permeation chromatography ( GPC ) , differential scanning calorimetry (DSC) and tensile testing. The results showed that MCO had high enough reactivity to obtain the PUs of high molecular weight,the number average molecular weight of PUs ranged from 41. 9×103 to 79. 0× 103 . Crosslinking of the PUs was realized by irradiating the PU solution with UV 365 nm light. The time for complete crosslinking of PU in solutions in the absence of light initiator ( 2-hydroxy-2-phenylacetophenone) was 25 min, but it was only 5 min in the presence of light initiator. The gel content increased with increasing MCO content in PUs when the PUs had the same soft segment; the gel content decreased with increasing soft segment molecular weight when the PUs had the same hard segment. Rational crosslinking contributed to the increase of tensile strength and shape recovery ratio,the shape recovery

  14. Evolutionary side-steps

    OpenAIRE

    Sluys,Ronald

    1992-01-01

    Many of the lower metazoans reach adulthood via complex developmental stages. Each of these stages is described with a specialized terminology, which is different for every major group of organisms. Biologists with a proper training in biodiversity may have learned about these complex issues during their undergraduate days, but many of us do no longer encounter the intricacies of lower metazoan development in later stages of our careers. We may be familiar with the ontogenetic stages in the g...

  15. Electrochemical impedance spectroscopy study of a surface confined redox reaction: The reduction of azobenzene on mercury in the absence of diffusion

    Energy Technology Data Exchange (ETDEWEB)

    Prieto, Francisco, E-mail: dapena@us.es [Department of Physical Chemistry, University of Seville, c/Profesor Garcia Gonzalez no 2, 41012 Seville (Spain); Rueda, Manuela; Hidalgo, Jose; Martinez, Elisa; Navarro, Inmaculada [Department of Physical Chemistry, University of Seville, c/Profesor Garcia Gonzalez no 2, 41012 Seville (Spain)

    2011-09-30

    The kinetics of azobenzene reduction on mercury electrodes in the absence of diffussional mass transport is studied by electrochemical impedance spectroscopy (EIS) in acetic acid/acetate buffered solutions at different pH values. Cyclic voltammetry experiments confirm the absence of diffusion effects and provide the values of the surface equilibrium potential. The analysis of the impedance frequency spectrums at every potential within the faradaic region conforms well the model and provides the global rate constant of the process, k{sub f}. The potential dependence of k{sub f} suggests the existence of an EE mechanism, with two electron transfers controlling the overall rate. The kinetic parameters of every step are obtained and their pH dependences clarify the role played by the protonation steps.

  16. Two-sided Internet Platforms: A Business Model Lifecycle Perspective

    OpenAIRE

    Muzellec, Laurent; Ronteau, Sébastien; Lambkin, Mary

    2015-01-01

    Multi-sided platforms bring together two or more distinct but interdependent groups of customers, normally described as B2B and B2C. Two-sided platforms have proliferated rapidly with the Internet and this has led to the development of new business models to monetize innovative value propositions in online markets. This paper puts forward a model of the evolution of the marketing strategies and business models of two-sided Internet businesses. In this model, Internet inter...

  17. Empirical Study on the Group-buying Market Scale in China Based on the Two-sided Markets Theory%基于双边市场理论的我国团购市场规模影响因素实证分析

    Institute of Scientific and Technical Information of China (English)

    阎冬媛; 钱燕云

    2015-01-01

    团购已成为我国商家的新型营销模式和消费者的时尚购物方式,在某种程度上实现了市场双赢的效果,而商家和消费者作为市场中两个重要的参与主体,其行为之间存在相互影响。基于双边市场理论,采用格兰杰因果检验方法,研究了团购市场的双边市场特征。结果表明,我国团购市场是具有明显交叉网络外部性的双边市场。利用时间序列模型和面板数据,分析了双边规模的影响因素。实证结果显示,我国团购市场商户规模与消费者规模的相关度较高,电子消费者规模受物价水平和消费习惯的影响,并据此提出了有利于我国团购市场健康有序发展的建议。%Group-buying has become a new marketing mode to sellers and a fashionable purchasing pattern to consumers,and makes the market a win-win result to some extent.Sellers and consumers are two main groups of market and may affect each other.The characteristics of group-buying market were analyzed by using the Granger causality test method based on the two-sided markets theory.The results show that the group-buying market is a kind of two-sided market with obvious cross network externality in China.Furthermore,the influencing factors of group-buying market were inspected by using a time series model and panel data.Some conclusions have been made that the correlation between business scale and consumer scale is high,CPI and spending habits affect the scale of consumers.The advices and suggestions for the sound and orderly development of group-buying market in China were put forward.

  18. Blind loop perforation after side-to-side ileocolonic anastomosis.

    Science.gov (United States)

    Valle, Raffaele Dalla; Zinicola, Roberto; Iaria, Maurizio

    2014-08-27

    Blind loop syndrome after side-to-side ileocolonic anastomosis is a well-recognized entity even though its incidence and complication rates are not clearly defined. The inevitable dilation of the ileal cul-de-sac leads to stasis and bacterial overgrowth which eventually leads to mucosal ulceration and even full-thickness perforation. Blind loop syndrome may be an underestimated complication in the setting of digestive surgery. It should always be taken into account in cases of acute abdomen in patients who previously underwent right hemicolectomy. We herein report 3 patients who were diagnosed with perforative blind loop syndrome a few years after standard right hemicolectomy followed by a side-to-side ileocolonic anastomosis.

  19. Blind loop perforation after side-to-side ileocolonic anastomosis

    Institute of Scientific and Technical Information of China (English)

    Raffaele; Dalla; Valle; Roberto; Zinicola; Maurizio; Iaria

    2014-01-01

    Blind loop syndrome after side-to-side ileocolonic anas-tomosis is a well-recognized entity even though its in-cidence and complication rates are not clearly defined. The inevitable dilation of the ileal cul-de-sac leads to stasis and bacterial overgrowth which eventually leads to mucosal ulceration and even full-thickness perfora-tion. Blind loop syndrome may be an underestimated complication in the setting of digestive surgery. It should always be taken into account in cases of acute abdomen in patients who previously underwent right hemicolectomy. We herein report 3 patients who were diagnosed with perforative blind loop syndrome a few years after standard right hemicolectomy followed by a side-to-side ileocolonic anastomosis.

  20. Side Effects in Steering Fragments

    CERN Document Server

    Wortel, Lars

    2011-01-01

    In this thesis I will give a formal definition of side effects. I will do so by modifying a system for modelling program instructions and program states, Quantified Dynamic Logic, to a system called DLAf (for Dynamic Logic with Assignments as Formulas), which in contrast to QDL allows assignments in formulas and makes use of short-circuit evaluation. I will show the underlying logic in those formulas to be a variant of short-circuit logic called repetition-proof short-circuit logic. Using DLAf I will define the actual and the expected evaluation of a single instruction. The side effects are then defined to be the difference between the two. I will give rules for composing those side effects in single instructions, thus scaling up our definition of side effects to a definition of side effects in deterministic \\dlaf-programs. Using this definition I will give a classification of side effects, introducing as most important class that of marginal side effects. Finally, I will show how to use our system for calcul...

  1. Side-View Face Recognition

    OpenAIRE

    Santemiz, Pinar; Spreeuwers, Luuk J.; Veldhuis, Raymond N. J.

    2010-01-01

    Side-view face recognition is a challenging problem with many applications. Especially in real-life scenarios where the environment is uncontrolled, coping with pose variations up to side-view positions is an important task for face recognition. In this paper we discuss the use of side view face recognition techniques to be used in house safety applications. Our aim is to recognize people as they pass through a door, and estimate their location in the house. Here, we compare available databas...

  2. Profit-shifting in two-sided markets

    OpenAIRE

    Schindler, Dirk; Schjelderup, Guttorm

    2009-01-01

    We investigate how multinational two-sided platform firms set their prices on intra firm transactions. Two-sided platform firms derive income from two customer groups that are connected through at least one positive network externality from one group to the other. A main finding is that even in the absence of taxation transfer prices deviate from marginal cost of production. A second result of the paper is that it is inherently difficult to establish arm s length prices in two sided-markets. ...

  3. The Moon's near side megabasin and far side bulge

    CERN Document Server

    Byrne, Charles

    2013-01-01

    Since Luna and Lunar Orbiter photographed the far side of the Moon, the mysterious dichotomy between the face of the Moon as we see it from Earth and the side of the Moon that is hidden has puzzled lunar scientists. As we learned more from the Apollo sample return missions and later robotic satellites, the puzzle literally deepened, showing asymmetry of the crust and mantle, all the way to the core of the Moon. This book summarizes the author’s successful search for an ancient impact feature, the Near Side Megabasin of the Moon and the extensions to impact theory needed to find it. The implications of this ancient event are developed to answer many of the questions about the history of the Moon.

  4. 基于供给侧改革视域的煤炭市场治理及政策建议--以中平能化集团为例%Coal market governing and policy orientation basing upon field of vision on supply-side reform:A case study of China Pingmei Shenma Group

    Institute of Scientific and Technical Information of China (English)

    颜林

    2016-01-01

    The underlying cause of China Pingmei Shenma Group suffering cold winter of coal market was excess production capacity,and the cause of excess production was supply of coal keep increasing which leading speed increasing of coal demanding decreases,therefore,basing up-on coal market countermeasures on field of vision from supply-side reform,the author provided policy orientation for China Pingmei Shenma Group,including enterprises'subsidy,strictly con-trolling production and usage of fault coal,expanding marketing strategies and improving mining technologies.%中平能化集团煤炭市场遭遇“寒冬季”的深层原因在于产能过剩,而造成产能过剩的原因来自于煤炭供给持续增加,煤炭需求增速下降。因此提出了基于供给侧改革视域的煤炭市场治理对策,包括企业补贴、严格控制劣质煤生产使用、拓展中平能化集团煤炭销售策略、提升集团产煤技术。

  5. 含偶氮苯结构聚酯的合成及性能%Synthesis and propertiesof polyesters containing azobenzene unit

    Institute of Scientific and Technical Information of China (English)

    于世钧; 高博; 王璐; 王红; 高永久

    2011-01-01

    Three novel linear polyesters(P1~P3) containing azobenzene unit are synthesized by condensation polymerization of diethyl 5-(4-alkoxy phenylazo) isophthalate and different glycols(l,3-propyl-ene glycol, 1,6-hexylene glycol, polyethylene glycol-400). The structure and properties of the polyes-ters(Pl~P3) are confirmed by IR, UV-vis, 'H NMR, SEC and TG-DTA. Polyesters(Pl~P3) containing azobenzene unit dissolve in common organic solvents such as tetrahydrofuran and chloroform, et al The intrinsic viscosities of polyesters(Pl~P3) in chloroform are 0. 514 6, 0. 463 9,0. 565 7 dL/g, the Mw are 39 200,34 983,45 507 g/mol, 5% weight loss temperature of polyesters(P1~P3) are 287,276,335 V. Polyesters(P1~P3) take place trans-cis photoisomerization under 365 run UV irradiation. With the ultraviolet excitation at 350 nm, polyesters(Pl~P3) emit purple fluorescence at 398 nm.%以间苯二甲酸为原料合成了5-[4-(乙氧基)苯基偶氮]-1,3-苯二甲酸二乙酯,分别与1,3-丙二醇、1,6-己二醇和聚乙二醇-400熔融聚合得到了3种新型含有偶氮苯结构的线型聚酯(P1~P3),采用IR、UV-vis、1H NMR、SEC和TG-DTA等对聚酯结构和性能进行了表征.聚酯(P1~P3)易溶于THF、CHCl3等有机溶剂,特性黏度分别为0.514 6、0.463 9、0.565 7 dL/g,Mw分别为39 200、34 983、45 507 g/mol,5%失重温度分别为287、276、335℃.在365 nm紫外光照射下,聚酯(P1~P3)中偶氮苯结构发生反-顺异构化,在350 nm波长光激发下,聚酯(P1~P3)在398 nm附近发紫色光.

  6. EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (CEF); Scientific Opinion on Flavouring Group Evaluation 13, Revision 2 (FGE.13 Rev2) Furfuryl and furan derivatives with and without additional side-chain substituents and heteroatoms from chemical group 14

    DEFF Research Database (Denmark)

    Larsen, John Christian; Nørby, Karin Kristiane; Beltoft, Vibe Meister;

    The Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids of the European Food Safety Authority was requested to evaluate 27 flavouring substances in the Flavouring Group Evaluation 13, Revision 2, using the Procedure in Commission Regulation (EC) No 1565/2000. Three of the su...... of commerce have also been considered. Adequate specifications including complete purity criteria and identity for the materials of commerce have been provided for all 24 flavouring substances evaluated through the Procedure....

  7. Interaction between two side-by-side inverted flags

    Science.gov (United States)

    Huertas-Cerdeira, Cecilia; Fan, Boyu; Barizien, Antoine; Gharib, Morteza

    2015-11-01

    The inverted flag instability occurs when an elastic plate that is free at its leading edge and clamped at its trailing edge is subjected to an axial wind. The oscillating motion that follows has received recent attention. However, previous studies have focused on the dynamics of a single flag even though these are rarely found isolated in natural phenomena, such as the fluttering of leaves in the wind. The interaction between two side-by-side inverted flags has been investigated, analyzing the effects of the distance between flags and the wind speed. Both in-phase and anti-phase coupling have been observed for different ranges of these parameters.

  8. Running away from side effects

    DEFF Research Database (Denmark)

    Casla, S; Hojman, P; Márquez-Rodas, I;

    2015-01-01

    The number of breast cancer survivors increases every year, thanks to the development of new treatments and screening techniques. However, patients present with numerous side effects that may affect their quality of life. Exercise has been demonstrated to reduce some of these side effects...... be an integrative complementary intervention to improve physiological, physical and psychological factors that affect survival and quality of life of these patients. For that reason, the main objective of this review is to provide a general overview of exercise benefits in breast cancer patients and recommendations......, but in spite of this, few breast cancer patients know and follow the exercise recommendations needed to remain healthy. In this review, we describe the different breast cancer treatments and the related side effects and implications of exercise in relation to these. We propose that exercise could...

  9. Side Effects of Side Effects Information in Drug Information Leaflets.

    Science.gov (United States)

    Maat, H. Pander; Klaassen, R.

    1994-01-01

    Describes a study in which drug information leaflets given to patients were improved in two ways, first by adding a short introductory paragraph on the nature of side effects generally, and second by adjusting frequency descriptors to more accurately reflect pretesting of the drug. Explains that participants in the study were less likely to…

  10. Dark Side of the Universe

    CERN Document Server

    2016-01-01

    The Dark Side of the Universe (DSU) workshops bring together a wide range of theorists and experimentalists to discuss current ideas on models of the dark side, and relate them to current and future experiments. This year's DSU will take place in the colorful Norwegian city of Bergen. Topics include dark matter, dark energy, cosmology, and physics beyond the standard model. One of the goals of the workshop is to expose in particular students and young researchers to the fascinating topics of dark matter and dark energy, and to provide them with the opportunity to meet some of the best researchers in these areas .

  11. Side-View Face Recognition

    OpenAIRE

    Santemiz, Pinar; Spreeuwers, Luuk J.; Veldhuis, Raymond N. J.; Biggelaar, van den, M.

    2011-01-01

    As a widely used biometrics, face recognition has many advantages such as being non-intrusive, natural and passive. On the other hand, in real-life scenarios with uncontrolled environment, pose variation up to side-view positions makes face recognition a challenging work. In this paper we discuss the use of side-view face recognition in house safety applications. Our goal is to recognize people as they pass through doors in order to estimate their location in the house. In order to preserve p...

  12. Opiates and elderly: Use and side effects

    Directory of Open Access Journals (Sweden)

    Diane L Chau

    2008-06-01

    Full Text Available Diane L Chau1, Vanessa Walker2, Latha Pai3, Lwin M Cho4University of Nevada School of Medicine, Reno, NV, USA 1Division Geriatric Medicine, 2Internal Medicine, 3Psychiatry, 4Geriatric Medicine, Sierra Nevada Healthcare System, Veterans Affairs Medical Center, Reno, NV, USAAbstract: The evaluation of pain and the subsequent issue of pain control is a clinical challenge that all healthcare providers face. Pain in the elderly population is especially difficult given the myriad of physiological, pharmacological, and psychological aspects of caring for the geriatric patient. Opiates are the mainstay of pain treatment throughout all age groups but special attention must be paid to the efficacy and side effects of these powerful drugs when prescribing to a population with impaired metabolism, excretion and physical reserve. In a random chart review of 300 US veterans, 44% of those receiving an analgesic also received opioids. The increasing use of opiates for pain management by healthcare practitioners requires that those prescribing opioids be aware of the special considerations for treating the elderly. This article will address the precautions one must take when using opiates in the geriatric population, as well as the side effects and ways to minimize them.Keywords: opiates, pain, elderly, side effects

  13. Side effects of external tooth bleaching

    DEFF Research Database (Denmark)

    E.M., Bruzell; Pallesen, Ulla; Thoresen, N.R.;

    2013-01-01

    -office = 39.3% [n = 28]; p >0.05; 95% CI [OR]: 0.198‑1.102) whereas prevalence of gingival irritation was higher after in-office treatment (at-home = 14.0%; in-office = 35.7%; p ... attributed to the bleaching treatment in the at-home and in-office groups, respectively. Predictors for side effects were tooth sensitivity, surface loss and gingivitis when observed at inclusion. Treatment-related predictors were bleaching concentration and contact between tray and gingiva. Conclusions...

  14. Research in Optical Properties of Azobenzene Doped Polymer%偶氮苯聚合物薄膜的光学性质研究

    Institute of Scientific and Technical Information of China (English)

    谢茹胜; 赵有源

    2012-01-01

    The UV-Vis absorption of the azobenzene doped polymersample is measured and analyzed. In the nonresonant absorption, its photo-induced birefringence is studied. The relation of photo-induced birefringence signal and polarization angle is measured and the experimental result fits the theoretical curve well. Furthermore, it possesses large photo-induced birefringence signal and the characteristic of long-term optical storage. On this basis, the optical holographic storage was achieved by using molecular orientation.%对偶氮苯聚合物薄膜各组分进行光谱特性分析,并在非吸收区用光泵浦测试法研究了薄膜光致双折射及其与偏振角度的关系,得出实验曲线与理论曲线相吻合的结果.该聚合物薄膜具有较大的光致双折射和长久存储特性.利用分子取向实现了全息存储实验,说明样品薄膜具有良好的光学性质.

  15. Trajectory-based nonadiabatic molecular dynamics without calculating nonadiabatic coupling in the avoided crossing case: trans↔cis photoisomerization in azobenzene.

    Science.gov (United States)

    Yu, Le; Xu, Chao; Lei, Yibo; Zhu, Chaoyuan; Wen, Zhenyi

    2014-12-21

    We develop a novel method to simulate analytical nonadiabatic switching probability based on effective coupling and effective collision energy by using only electronic adiabatic potential energy surfaces and its gradients in the case of avoided crossing types of nonadiabatic transitions. In addition, the present method can keep the same time step for computing both on-the-fly trajectory and nonadiabatic transitions accurately. The present method is most useful for localized nonadiabatic transitions induced by conical intersection. We employ the on-the-fly surface hopping algorithm with an ab initio quantum chemistry calculation to demonstrate a dynamic simulation for photoisomerization in azobenzene. Simulated quantum yield and lifetime converge to 0.39 and 53 femtosecond, respectively (0.33 and 0.81 picosecond) for cis-to-trans (trans-to-cis) photoisomerization with up to 800 (600) sampling trajectories. The present results agree well with those of the experiment, as well as results simulated with use of nonadiabatic coupling within Tully's fewest switching method. The present trajectory-based nonadiabatic molecular dynamics free from nonadiabatic coupling greatly enhances the simulation power of molecular dynamics for large complex chemical systems.

  16. Immediate Small Side Branch Occlusion after Percutaneous Coronary Intervention

    Directory of Open Access Journals (Sweden)

    Mohammad Ali Ostovan

    2007-09-01

    Full Text Available Background: Small side branches, albeit less important than their larger counterparts, have not yet received due attention in the literature. Nor has there ever been a comparison between drug-eluting stents and bare metal stents apropos side branch occlusion. The aim of this study was to compare the patency of small (≥0.5 and ≤1.5 mm in diameter side branches with respect to bare metal vs. drug-eluting stents immediately after their deployment.Methods: This prospective bi-center study, conducted between June 2005 and January 2007, enrolled 82 patients treated with ≥1 of two stents (TAXUSTM LiberteTM or LiberteTM. Side branches ≥0.5 and <1.5 mm in diameter arising from the main vessel at the lesion site were evaluated. Results: Thirty-eight patients were treated with 42 LiberteTM stents (58 side branches and forty-four patients with 50 TAXUSTM LiberteTM (102 side branches. The rate of small side branch occlusion was 35.3% (36 in the TAXUSTM LiberteTM group compared to 29.31% (15 in the LiberteTM group (P-value= 0.7. The presence of type 1 side branch morphology (Lefevre classification was the most powerful predictor of small side branch occlusion (P-value=0.03. Conclusion: This study shows that drug-eluting stents are not inferior to bare metal stents as regards small side branch occlusion during coronary stenting

  17. Identifying Two-Sided Markets

    NARCIS (Netherlands)

    Filistrucchi, L.; Geradin, D.A.A.G.; van Damme, E.E.C.

    2012-01-01

    Abstract: We review the burgeoning literature on two-sided markets focusing on the different definitions that have been proposed. In particular, we show that the well-known definition given by Evans is a particular case of the more general definition proposed by Rochet and Tirole. We then identify t

  18. The DarkSide Program

    Directory of Open Access Journals (Sweden)

    Rossi B.

    2016-01-01

    Full Text Available DarkSide-50 at Gran Sasso underground laboratory (LNGS, Italy, is a direct dark matter search experiment based on a liquid argon TPC. DS-50 has completed its first dark matter run using atmospheric argon as target. The detector performances and the results of the first physics run are presented in this proceeding.

  19. Control mechanism and technique of floor heave with reinforcing solid coal side and floor corner in gob-side coal entry retaining

    Institute of Scientific and Technical Information of China (English)

    Chen; Yong; Bai; Jianbiao; Yan; Shuai; Xu; Ying; Wang; Xiangyu; Ma; Shuqi

    2012-01-01

    Floor heave is the most common convergence in gob-side entry retaining.The paper analyzes the form,process and characteristics of gob-side entry retaining with the comprehensive methods of theoretical analysis,numerical simulation and the field trial.Research results present that bending and folding floor heave is the main factor in the stage of the first panel mining;squeezing and fluidity floor heave plays a great role in the stable stage of gob-side entry retaining;the combination of the former two factors affects mainly the stage of the second mining ahead;abutment pressure is a fundamental contribution to the serious floor heave of gob-side entry retaining,and sides corners of solid coal body are key part in the case of floor heave controlling of gob-side entry retaining.Floor heave of gob-side entry retaining can be significantly controlled by reinforcing sides and corners of solid coal body,and influence rules on the floor heave of gob side entry retaining of sides supporting strength and the bottom bolt orientation in solid coal side are obtained.Research results have been successfully applied in gob-side entry retaining of G20-F23070 face haulage roadway in #2 coal mine of Pingmei Group,and the field observation shows that the proposed technique is an effective way in controlling the floor heave of gob-side entry retaining.

  20. Control mechanism and technique of floor heave with reinforcing solid coal side and floor corner in gob-side coal entry retaining

    Institute of Scientific and Technical Information of China (English)

    Chen Yong; Bai Jianbiao; Yan Shuai; Xu Ying; Wang Xiangyu; Ma Shuqi

    2012-01-01

    Floor heave is the most common convergence in gob-side entry retaining.The paper analyzes the form,process and characteristics of gob-side entry retaining with the comprehensive methods of theoretical analysis,numerical simulation and the field trial.Research results present that bending and folding floor heave is the main factor in the stage of the first panel mining; squeezing and fluidity floor heave plays a great role in the stable stage of gob-side entry retaining; the combination of the former two factors affects mainly the stage of the second mining ahead; abutment pressure is a fundamental contribution to the serious floor heave of gob-side entry retaining,and sides comers of solid coal body are key part in the case of floor heave controlling of gob-side entry retaining.Floor heave of gob-side entry retaining can be significantly controlled by reinforcing sides and comers of solid coal body,and influence rules on the floor heave of gob side entry retaining of sides supporting strength and the bottom bolt orientation in solid coal side are obtained.Research results have been successfully applied in gob-side entry retaining of G20-F23070 face haulage roadway in #2 coal mine of Pingmei Group,and the field observation shows that the proposed technique is an effective way in controlling the floor heave of gob-side entry retaining.

  1. 49 CFR 229.69 - Side bearings.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Side bearings. 229.69 Section 229.69....69 Side bearings. (a) Friction side bearings with springs designed to carry weight may not have more than 25 percent of the springs in any one nest broken. (b) Friction side bearings may not be run...

  2. Prevalence of left-sided melanomas in an Irish population.

    LENUS (Irish Health Repository)

    de Blacam, C

    2012-02-01

    BACKGROUND: A predominance of melanomas on the left side of the body has recently been described. No associations between tumour laterality and gender, age or anatomical site have been identified. AIM: The aim of this study was to investigate the prevalence of left-sided melanomas in an Irish population and to examine potential associations with various patient and tumour characteristics. METHODS: A retrospective chart review of patients with cutaneous melanoma who were treated over a 10-year period was carried out. Lateral distribution of melanoma on either side of the body was compared using chi(2) analysis and evaluated by gender, age group, anatomic location, histologic subtype and Breslow depth. RESULTS: More melanomas occurred on the left side (57%, P = 0.015), and this finding was particularly significant in females. For both genders combined, there were no statistically significant differences in laterality by age group, anatomic location, type of melanoma and Breslow depth. There were significantly more superficial spreading melanomas on the left side in both men and women. CONCLUSIONS: This study demonstrates a predominance of left-sided melanomas in Irish patients. While a number of demographic and molecular associations have been proposed, further research is required to fully explain this phenomenon.

  3. Prevalence of left-sided melanomas in an Irish population.

    LENUS (Irish Health Repository)

    de Blacam, C

    2011-04-17

    BACKGROUND: A predominance of melanomas on the left side of the body has recently been described. No associations between tumour laterality and gender, age or anatomical site have been identified. AIM: The aim of this study was to investigate the prevalence of left-sided melanomas in an Irish population and to examine potential associations with various patient and tumour characteristics. METHODS: A retrospective chart review of patients with cutaneous melanoma who were treated over a 10-year period was carried out. Lateral distribution of melanoma on either side of the body was compared using χ(2) analysis and evaluated by gender, age group, anatomic location, histologic subtype and Breslow depth. RESULTS: More melanomas occurred on the left side (57%, P = 0.015), and this finding was particularly significant in females. For both genders combined, there were no statistically significant differences in laterality by age group, anatomic location, type of melanoma and Breslow depth. There were significantly more superficial spreading melanomas on the left side in both men and women. CONCLUSIONS: This study demonstrates a predominance of left-sided melanomas in Irish patients. While a number of demographic and molecular associations have been proposed, further research is required to fully explain this phenomenon.

  4. Improved side information generation for distributed video coding

    DEFF Research Database (Denmark)

    Huang, Xin; Forchhammer, Søren

    2008-01-01

    information generation method, fewer bits will be requested from the encoder and more reliable decoded frames will be obtained. In this paper, a side information generation method is introduced to further improve the rate-distortion (RD) performance of transform domain distributed video coding. This algorithm......As a new coding paradigm, distributed video coding (DVC) deals with lossy source coding using side information to exploit the statistics at the decoder to reduce computational demands at the encoder. The performance of DVC highly depends on the quality of side information. With a better side...... consists of a variable block size based Y, U and V component motion estimation and an adaptive weighted overlapped block motion compensation (OBMC). The proposal is tested and compared with the results of an executable DVC codec released by DISCOVER group (DIStributed COding for Video sERvices). RD...

  5. STUDY ON SIDE REACTION IN THE SYNTHESIS OF HYPERCROSSLINKED POLYMERS

    Institute of Scientific and Technical Information of China (English)

    ZHANG Bo; LI Aimin; TAO Weihua; YANG Weiben

    2008-01-01

    The systematical study about side reactions have revealed the formation mechanism of oxygen-containing groups of hypercrosslinked polymers.Surface chemistry and functionality of the polymers are characterized by Fourier-transform infrared spectroscopy (FT-IR), solid state nuclear magnetic resonance (NMR) and contact angle.The results showed that the ether groups were from chioromethylated reaction, and the alcohol groups arose from partial hydrolysis of chloromethyl groups during the post-crosslinking reaction, and the carbonyl functionality was formed by further oxidation of the alcohol groups.Catalyst and solvent used in the postcrosslinking reaction would greatly influence the surface chemistry of the polymer.

  6. STUDY ON SIDE REACTION IN THE SYNTHESIS OF HYPERCROSSLINKED POLYMERS

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The systematical study about side reactions have revealed the formation mechanism of oxygen-containing groups of hypercrosslinked polymers. Surface chemistry and functionality of the polymers are characterized by Fourier-transform infrared spectroscopy (FT-IR), solid state nuclear magnetic resonance (NMR) and contact angle. The results showed that the ether groups were from chloromethylated reaction, and the alcohol groups arose from partial hydrolysis of chloromethyl groups during the post-crosslinking reaction, and the carbonyl functionality was formed by further oxidation of the alcohol groups. Catalyst and solvent used in the postcrosslinking reaction would greatly influence the surface chemistry of the polymer.

  7. THE TWO SIDES OF MONEY LAUNDERING

    Directory of Open Access Journals (Sweden)

    Corina – Maria ENE

    2014-12-01

    Full Text Available The mainly goal of money laundering is to carry out more and more illegal economic transactions or activities to produce individual or groups gains and then to legitimate them. Money laundering converts illicit source of money generated by criminal activities in order to hide the connection between money and their original illegal activities. This is one of money laundering side. The second side implies corruption. While money laundering is a passing channel for illicit funds due to its criminal origin source, such funds may derive from corruption offences. All corruption’s forms represent the most important illicit funds branches for money laundering process. Corrupt people methods used to exploit the national and international financial system reflect the relationship between those two criminal activities. Criminals achieve their personal interests by hiding their corruption proceeds and transfer these gains to official economies. Corruption spread in any society entails money laundering spread, and the converse, too. There is a quite “indecent” relationship between money laundering and corruption. This paper tries to identify the multiple connections between the two phenomenons showing the negative impacts these criminal behaviours are having on the national and international economy. We conclude by highlighting the necessity of a multidisciplinary approach in order to fight against money laundering and corruption by integrating these problem frameworks at national level. International community must focus their resources on money laundering and corruption risks areas and maximize their response impact.

  8. Shortest Paths With Side Sensors

    CERN Document Server

    Salaris, Paolo; Bicchi, Antonio

    2011-01-01

    We present a complete characterization of shortest paths to a goal position for a vehicle with unicycle kinematics and a limited range sensor, constantly keeping a given landmark in sight. Previous work on this subject studied the optimal paths in case of a frontal, symmetrically limited Field--Of--View (FOV). In this paper we provide a generalization to the case of arbitrary FOVs, including the case that the direction of motion is not an axis of symmetry for the FOV, and even that it is not contained in the FOV. The provided solution is of particular relevance to applications using side-scanning, such as e.g. in underwater sonar-based surveying and navigation.

  9. Acute and long-term psychiatric side effects of mefloquine

    DEFF Research Database (Denmark)

    Ringqvist, Åsa; Bech, Per; Glenthøj, Birte;

    2015-01-01

    ), and vitality (VT) in the mefloquine group compared to matched controls. CONCLUSION: The most frequent acute psychiatric problems were anxiety, depression, and psychotic symptoms. Data indicated that subjects experiencing acute mefloquine adverse side effects may develop long-term mental health problems...... with a decreased sense of global quality of life with lack of energy, nervousness, and depression....

  10. 49 CFR 238.217 - Side structure.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Side structure. 238.217 Section 238.217 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Equipment § 238.217 Side structure. Each passenger car shall comply with the following: (a) Side posts...

  11. Dearomatization Reactions of N-Heterocycles Mediated by Group 3 Complexes

    Energy Technology Data Exchange (ETDEWEB)

    Miller, Kevin L [Univ. of California, Los Angeles, CA (United States); Williams, Bryan N [Univ. of California, Los Angeles, CA (United States); Benitez, Diego [California Inst. of Technology (CalTech), Pasadena, CA (United States); Carver, Colin T [Univ. of California, Los Angeles, CA (United States); Ogilby, Kevin R [Univ. of California, Los Angeles, CA (United States); Tkatchouk, Ekaterina [California Inst. of Technology (CalTech), Pasadena, CA (United States); Goddard, William A [California Inst. of Technology (CalTech), Pasadena, CA (United States); Diaconescu, Paula L [Univ. of California, Los Angeles, CA (United States)

    2010-01-13

    Group 3 (Sc, Y, Lu, La) benzyl complexes supported by a ferrocene diamide ligand are reactive toward aromatic N-heterocycles by mediating their coupling and, in a few cases, the cleavage of their C-N bonds. When these complexes reacted with 2,2'-bipyridine or isoquinoline, they facilitated the alkyl migration of the benzyl ligand onto the pyridine ring, a process accompanied by the dearomatization of the N-heterocycle. The products of the alkyl-transfer reactions act as hydrogen donors in the presence of aromatic N-heterocycles, ketones, and azobenzene. Experimental and computational studies suggest that the hydrogen transfer takes place through a concerted mechanism. An interesting disproportionation reaction of the dearomatized, alkyl-substituted isoquinoline complexes is also reported.

  12. The Lighter Side of Gravity

    Science.gov (United States)

    Narlikar, Jayant Vishnu

    1996-10-01

    From the drop of an apple to the stately dance of the galaxies, gravity is omnipresent in the Cosmos. Even with its high profile, gravity is the most enigmatic of all the known basic forces in nature. The Lighter Side of Gravity presents a beautifully clear and completely nontechnical introduction to the phenomenon of this force in all its manifestations. Astrophysicist Jayant Narlikar begins with an historical background to the discovery of the law of gravitation by Isaac Newton in the seventeenth century. Using familiar analogies, interesting anecdotes, and numerous illustrations to get across subtle effects and difficult points to readers, he goes on to describe the general theory of relativity and some of its strange and unfamiliar ideas such as curved spacetime, the bending of light, and black holes. Since first publication in 1982 (W.H. Freeman), Dr. Narlikar has brought his book completely up to date and expanded it to include the discovery of gigantic gravitational lenses in space, the findings of the Cosmic Background Explorer (COBE) satellite, the detection of dark matter in galaxies, the investigation of the very early Universe, and other new ideas in cosmology. This lucid and stimulating book presents a clear approach to the intriguing phenomenon of gravity for everyone who has ever felt caught in its grip. Jayant Narlikar is the winner of many astronomical prizes and the author of Introduction to Cosmology (Cambridge University Press, 1993).

  13. Distributed video coding with multiple side information

    DEFF Research Database (Denmark)

    Huang, Xin; Brites, C.; Ascenso, J.;

    2009-01-01

    Distributed Video Coding (DVC) is a new video coding paradigm which mainly exploits the source statistics at the decoder based on the availability of some decoder side information. The quality of the side information has a major impact on the DVC rate-distortion (RD) performance in the same way...... the quality of the predictions had a major impact in predictive video coding. In this paper, a DVC solution exploiting multiple side information is proposed; the multiple side information is generated by frame interpolation and frame extrapolation targeting to improve the side information of a single...... estimation mode. Compared with the best available single side information solutions, the proposed DVC solution with multiple side information robustly improves the RD performance for the set of test sequences....

  14. Car Side Structure Crashworthiness in Pole and Moving Deformable Barrier Side Impacts

    Institute of Scientific and Technical Information of China (English)

    WANG Dazhi; DONG Guang; ZHANG Jinhuan; HUANG Shilin

    2006-01-01

    To clearly understand passenger car structure's crashworthiness in typical side impacts of pole and moving deformable barrier (MDB) impact modes, which could assist the establishment of Chinese vehicle side impact safety regulations, a full midsized car finite element model, calibrated by pole side impact test, was built and the pole side impact according to European New Car Assessment Program (EuroNCAP) and the MDB side impact according to ECE R95 regulations were simulated with LS-DYNA. The accelerations and the structure deformations from simulations were compared. It can be concluded that the pole side impact focuses primarily on side structure crashworthiness as a result of large intrusions, while the MDB side impact focuses primarily on full side structure crashworthiness. Accordingly, occupant protection strategies focus on different aspects to improve side impact safety. In the pole side impact the objective is to maintain the passenger compartment and protect the passenger's head from impacting the pole, while in the MDB side impact the objective is to protect the full human body. In the design of the car side structures, at least these two tests should be considered for assessing their side impact crashworthiness. Conducting these two side impact tests as certified tests provides insights into car safety during side impacts.

  15. Right-side and left-side colon cancer follow different pathways to relapse

    OpenAIRE

    Bauer, Kerry M.; Hummon, Amanda B.; Buechler, Steven

    2011-01-01

    There is growing evidence that cancer of the ascending (right-side) colon is different from cancer of the descending (left-side) colon at the molecular level. Using microarray data from 102 right-side colon carcinomas and 95 left-side colon carcinomas we show that different pathways dominate progression to relapse in right-side and left-side colon cancer. Right-side tumors at a high risk for relapse exhibit elevated expression of cell cycle control genes and elevated Wnt signaling. On the oth...

  16. Triptans and CNS side-effects: pharmacokinetic and metabolic mechanisms.

    Science.gov (United States)

    Dodick, D W; Martin, V

    2004-06-01

    Triptans are the treatment of choice for acute migraine. While seemingly a homogenous group of drugs, results from a meta-analysis reveal significant differences in efficacy and tolerability among oral triptans. The incidence of drug-related central nervous system (CNS) side-effects with some triptans is as high as 15% and may be associated with functional impairment and reduced productivity. The occurrence of adverse events associated with triptans in general, and CNS side-effects in particular, may lead to a delay in initiating or even avoidance of an otherwise effective treatment. Potential explanations for differences among triptans in the incidence of CNS side-effects may relate to pharmacological and pharmacokinetic differences, including receptor binding, lipophilicity, and the presence of active metabolites. Of the triptans reviewed, at clinically relevant doses, almotriptan 12.5 mg, naratriptan 2.5 mg and sumatriptan 50 mg had the lowest incidence of CNS side-effects, while eletriptan 40 and 80 mg, rizatriptan 10 mg and zolmitriptan 2.5 and 5 mg had the highest incidence. The most likely explanations for the differences in CNS side-effects among triptans are the presence of active metabolites and high lipophilicity of the parent compound and active metabolites. Eletriptan, rizatriptan and zolmitriptan have active metabolites, while lipophilicity is lowest for almotriptan and sumatriptan. If CNS side-effects are a clinically relevant concern in the individual patient, use of a triptan with a low incidence of CNS side-effects may offer the potential for earlier initiation of treatment and more effective outcomes. PMID:15154851

  17. SIDE-EFFECTS OF GENERIC

    OpenAIRE

    Ružić, Klementina; Medved, Paola; Dadić-Hero, Elizabeta; Graovac, Mirjana; Tatalović-Vorkapić, Sanja; Rončević Gržeta, Ika

    2010-01-01

    New trends in medicine which are much more oriented towards pharmacoeconomy, are ever so common these days. There's an aim within the focus of the health system which is cutting down treatment expenses, and that relates to psychiatry practice too. Prescription drugs issued by specialist doctors are allowed to be switched with cheaper ones of the same group of drugs by GP doctors, with an aim of cost reduction. „Instead of the medicament prescribed, a GP doctor is allowed to prescribe...

  18. Interference Channels with Correlated Receiver Side Information

    OpenAIRE

    Liu, Nan; Gunduz, Deniz; Goldsmith, Andrea J.; Poor, H. Vincent

    2008-01-01

    The problem of joint source-channel coding in transmitting independent sources over interference channels with correlated receiver side information is studied. When each receiver has side information correlated with its own desired source, it is shown that source-channel code separation is optimal. When each receiver has side information correlated with the interfering source, sufficient conditions for reliable transmission are provided based on a joint source-channel coding scheme using the ...

  19. Constrained Source Coding with Side Information

    OpenAIRE

    Lapidoth, Amos; Malär, Andreas; Wigger, Michèle

    2013-01-01

    The source-coding problem with side information at the decoder is studied subject to a constraint that the encoder---to whom the side information is unavailable---be able to compute the decoder's reconstruction sequence to within some distortion. For discrete memoryless sources and finite single-letter distortion measures, an expression is given for the minimal description rate as a function of the joint law of the source and side information and of the allowed distortions at the encoder and ...

  20. Discriminatory Lossy Source Coding: Side Information Privacy

    OpenAIRE

    Tandon, Ravi; Sankar, Lalitha; Poor, H. Vincent

    2011-01-01

    A lossy source coding problem is studied in which a source encoder communicates with two decoders, one with and one without correlated side information with an additional constraint on the privacy of the side information at the uninformed decoder. Two cases of this problem arise depending on the availability of the side information at the encoder. The set of all feasible rate-distortion-equivocation tuples are characterized for both cases. The difference between the informed and uninformed ca...

  1. Nonparametric Analysis of Two-Sided Markets

    OpenAIRE

    Senay Sokullu

    2012-01-01

    This paper considers an empirical semiparametric model for two-sided markets. Contrary to existing empirical literature on two-sided markets, we do not rely on linear network effects. Instead, network effects and probability distribution functions of net benefits of two sides are specified nonparametrically. The demand functions and the network effect functions of readers and advertisers are estimated by nonparametric IV estimation using a data set from German magazine industry. The ill-posed...

  2. Physiological and skill demands of 'on-side' and 'off-side' games.

    Science.gov (United States)

    Gabbett, Tim J; Jenkins, David G; Abernethy, Bruce

    2010-11-01

    This study investigated the physiological and skill demands of 'on-side' and 'off-side' games in elite rugby league players. Sixteen male rugby league players participated in 'on-side' and 'off-side' games. Both small-sided games were played in a 40- × 40-m playing area. The 'off-side' game permitted players to have 3 'plays' while in possession of the ball. Players were permitted to pass backward or forward (to an 'off-side' player). The 'on-side' game also permitted players to have 3 'plays' while in possession of the ball. However, players were only permitted to pass backward to players in an 'on-side' position. Heart rate and movement patterns (via global positioning system) were recorded continuously throughout both games. Data were collected on the distance covered, number of high-acceleration and velocity efforts, and recovery between efforts. Video footage was also taken to track the performance of the players. Post hoc inspection of the footage was undertaken to count the number of possessions and the number and quality of disposals. In comparison to 'on-side' games, 'off-side' games had a greater number of involvements ("touches"), passes, and effective passes. However, the cognitive demands of 'on-side' games were greater than 'off-side' games. 'Off-side' games resulted in a greater total distance covered, greater distance covered in mild and moderate accelerations, and greater distance covered in low, moderate, and high-velocity efforts. There were also a greater number of short duration recovery periods between efforts in 'off-side' games. The results of this study demonstrate that 'off-side' games provide greater physiological and skill demands than 'on-side' games. 'Off-side' games may provide a practical alternative to 'on-side' games for the development of skill and fitness in elite rugby league players.

  3. The Coke Side of Life

    OpenAIRE

    Eriksen, Cecilie; Flydal Enevoldsen, Mette; Binesse, Dianne; Urwald, Maria; Lützau, Cæcilie

    2012-01-01

    The aim of this study is to examine, how a major corporation like the Coca-Cola Company, proceed in terms of attracting their wide audience by subconsciously implicating themselves in the minds of consumers worldwide. How does the firm reach their target groups, and what sort of strategies do they use to achieve this? We presume that the Coca-Cola Company takes use of communicative approaches that appeals to values incarnated into the receiver. In addition to this, we believe that these value...

  4. Source Coding With Encoder Side Information

    OpenAIRE

    Martinian, Emin; Wornell, Gregory W.; Zamir, Ram

    2004-01-01

    We introduce the idea of distortion side information, which does not directly depend on the source but instead affects the distortion measure. We show that such distortion side information is not only useful at the encoder, but that under certain conditions, knowing it at only the encoder is as good as knowing it at both encoder and decoder, and knowing it at only the decoder is useless. Thus distortion side information is a natural complement to the signal side information studied by Wyner a...

  5. Sexual side effects induced by psychotropic drugs

    DEFF Research Database (Denmark)

    Kristensen, Ellids

    2002-01-01

    The majority of psychotropic drugs entail sexual side effects. The sexual side effects may reduce quality of life and may give rise to non-compliance. For example, 30-60 per cent of patients treated with antidepressants are known to develop a sexual dysfunction. However, some psychotropic drugs...... with no or very few sexual side effects have begun to emerge. The treatment of sexual side effects induced by psychotropic drugs may consist of: modified sexual habits, reduction in dosage, switching to another medication, possibly in combination with different psychotropic agents, other varieties...

  6. Incentives for demand-side management

    Energy Technology Data Exchange (ETDEWEB)

    Reid, M.W.; Brown, J.B. [Barakat and Chamberlin, Inc., Oakland, CA (United States)

    1992-01-01

    This report is the first product of an ongoing project to monitor the efforts of states to remove regulatory barriers to, and provide financial incentives for, utility investment in demand-side management (DSM) resources. The project was commissioned by the National Association of Regulatory Utility Commissioners (NARUC) in response to growing interest among regulators for a comprehensive survey of developments in this area. Each state report beings with an overview of the state`s progress toward removing regulatory barriers and providing incentives for DSM. Information is organized under five headings: status; IRP regulations and practice; current treatment of DSM, directions and trends; commission contact person. Where applicable, each overview is followed by one or more sections that report on specific incentive proposals or mechanisms within the state. Information on each proposal or mechanism is organized under eight headings. A notation on each page identifies the utility or other group associated with the proposal or mechanism. The eight headings are as follows: status; background; treatment of cost recovery; treatment of lost revenues/decoupling; treatment of profitability; other features; issues, and additional observations.

  7. Incentives for demand-side management

    Energy Technology Data Exchange (ETDEWEB)

    Reid, M.W.; Brown, J.B. (Barakat and Chamberlin, Inc., Oakland, CA (United States))

    1992-01-01

    This report is the first product of an ongoing project to monitor the efforts of states to remove regulatory barriers to, and provide financial incentives for, utility investment in demand-side management (DSM) resources. The project was commissioned by the National Association of Regulatory Utility Commissioners (NARUC) in response to growing interest among regulators for a comprehensive survey of developments in this area. Each state report beings with an overview of the state's progress toward removing regulatory barriers and providing incentives for DSM. Information is organized under five headings: status; IRP regulations and practice; current treatment of DSM, directions and trends; commission contact person. Where applicable, each overview is followed by one or more sections that report on specific incentive proposals or mechanisms within the state. Information on each proposal or mechanism is organized under eight headings. A notation on each page identifies the utility or other group associated with the proposal or mechanism. The eight headings are as follows: status; background; treatment of cost recovery; treatment of lost revenues/decoupling; treatment of profitability; other features; issues, and additional observations.

  8. Identifying Cross-Sided Liquidity Externalities

    NARCIS (Netherlands)

    J.A. Skjeltorp (Johannes); E. Sojli (Elvira); W.W. Tham (Wing Wah)

    2013-01-01

    markdownabstract__Abstract__ We study the relevance of the cross-sided externality between liquidity makers and takers from the two-sided market perspective. We use exogenous changes in the make/take fee structure, minimum tick-size and technological shocks for liquidity takers and makers, as exper

  9. Classical data compression with quantum side information

    OpenAIRE

    Devetak, I.; Winter, A.

    2002-01-01

    The problem of classical data compression when the decoder has quantum side information at his disposal is considered. This is a quantum generalization of the classical Slepian-Wolf theorem. The optimal compression rate is found to be reduced from the Shannon entropy of the source by the Holevo information between the source and side information.

  10. Metabolic Network Prediction of Drug Side Effects.

    Science.gov (United States)

    Shaked, Itay; Oberhardt, Matthew A; Atias, Nir; Sharan, Roded; Ruppin, Eytan

    2016-03-23

    Drug side effects levy a massive cost on society through drug failures, morbidity, and mortality cases every year, and their early detection is critically important. Here, we describe the array of model-based phenotype predictors (AMPP), an approach that leverages medical informatics resources and a human genome-scale metabolic model (GSMM) to predict drug side effects. AMPP is substantially predictive (AUC > 0.7) for >70 drug side effects, including very serious ones such as interstitial nephritis and extrapyramidal disorders. We evaluate AMPP's predictive signal through cross-validation, comparison across multiple versions of a side effects database, and co-occurrence analysis of drug side effect associations in scientific abstracts (hypergeometric p value = 2.2e-40). AMPP outperforms a previous biochemical structure-based method in predicting metabolically based side effects (aggregate AUC = 0.65 versus 0.59). Importantly, AMPP enables the identification of key metabolic reactions and biomarkers that are predictive of specific side effects. Taken together, this work lays a foundation for future detection of metabolically grounded side effects during early stages of drug development. PMID:27135366

  11. Side-emitting fiber optic position sensor

    Energy Technology Data Exchange (ETDEWEB)

    Weiss, Jonathan D. (Albuquerque, NM)

    2008-02-12

    A side-emitting fiber optic position sensor and method of determining an unknown position of an object by using the sensor. In one embodiment, a concentrated beam of light source illuminates the side of a side-emitting fiber optic at an unknown axial position along the fiber's length. Some of this side-illuminated light is in-scattered into the fiber and captured. As the captured light is guided down the fiber, its intensity decreases due to loss from side-emission away from the fiber and from bulk absorption within the fiber. By measuring the intensity of light emitted from one (or both) ends of the fiber with a photodetector(s), the axial position of the light source is determined by comparing the photodetector's signal to a calibrated response curve, look-up table, or by using a mathematical model. Alternatively, the side-emitting fiber is illuminated at one end, while a photodetector measures the intensity of light emitted from the side of the fiber, at an unknown position. As the photodetector moves further away from the illuminated end, the detector's signal strength decreases due to loss from side-emission and/or bulk absorption. As before, the detector's signal is correlated to a unique position along the fiber.

  12. Study of turbine with side channel runner

    OpenAIRE

    Jandourek, Pavel

    2012-01-01

    This thesis deals with proposal of constructional solving turbine with side channel. Basis for the design is lossy characteristics of the valve. The intention is to replace hydraulic closures by turbine with side channel runner. Hydraulic losses in the flow restriction in turn replaced by the electricity generation in the comparable characteristics of valve and turbine.

  13. European side markers effect on traffic safety

    NARCIS (Netherlands)

    Roelfsema, A.; Theeuwes, J.; Alferdinck, J.W.A.M

    1999-01-01

    In 1993 new European legislation regarding side-markers for passenger cars became effective. Volvo requested the TNO-Human Factors Research Institute (HFRI) to investigate the possible safety benefit of this European side-markers configuration. A test panel at TNO- HFRI was used to determine the dif

  14. Phytochemicals that counteract the cardiotoxic side effects of cancer chemotherapy

    OpenAIRE

    Anita Piasek; Agnieszka Bartoszek; Jacek Namieśnik

    2009-01-01

    Almost all clinically used antitumor drugs exhibit toxic side effects affecting heart function. Because of cardiotoxicity during anticancer chemotherapy, effective doses of cytostatics have to be limited, which may worsen antitumor efficacy. The cardiotoxicity induced by cytostatics of the anthracycline group in particular results, among others, from massive stimulation of ROS. It has therefore been suggested that some phytochemicals with high antioxidant potential, when administered together...

  15. INFLUENCE OF ELECTROACUPUNCTURE ON ARTIFICIAL ABORTION-INDUCED SIDE EFFECTS

    Institute of Scientific and Technical Information of China (English)

    田丽颖

    2001-01-01

    In the present study, the effect of electroecupuncture (EA) of acupoints of Ren, Spleen and Stomach Meridians on artificial abortion-induced side effects was observed in 100 artificial abortion women. In comparison with 45 artificial abortion women in the control group (who had not accepted EA treatment), EA possessed significant effects in relieving abdominal pain, reducing vaginal bleeding duration, lowering infection rate and infertility rate after artificial abortion operation.

  16. Back-side readout semiconductor photomultiplier

    Science.gov (United States)

    Choong, Woon-Seng; Holland, Stephen E

    2014-05-20

    This disclosure provides systems, methods, and apparatus related to semiconductor photomultipliers. In one aspect, a device includes a p-type semiconductor substrate, the p-type semiconductor substrate having a first side and a second side, the first side of the p-type semiconductor substrate defining a recess, and the second side of the p-type semiconductor substrate being doped with n-type ions. A conductive material is disposed in the recess. A p-type epitaxial layer is disposed on the second side of the p-type semiconductor substrate. The p-type epitaxial layer includes a first region proximate the p-type semiconductor substrate, the first region being implanted with p-type ions at a higher doping level than the p-type epitaxial layer, and a second region disposed on the first region, the second region being doped with p-type ions at a higher doping level than the first region.

  17. Highly conductive side chain block copolymer anion exchange membranes.

    Science.gov (United States)

    Wang, Lizhu; Hickner, Michael A

    2016-06-28

    Block copolymers based on poly(styrene) having pendent trimethyl styrenylbutyl ammonium (with four carbon ring-ionic group alkyl linkers) or benzyltrimethyl ammonium groups with a methylene bridge between the ring and ionic group were synthesized by reversible addition-fragmentation radical (RAFT) polymerization as anion exchange membranes (AEMs). The C4 side chain polymer showed a 17% increase in Cl(-) conductivity of 33.7 mS cm(-1) compared to the benzyltrimethyl ammonium sample (28.9 mS cm(-1)) under the same conditions (IEC = 3.20 meq. g(-1), hydration number, λ = ∼7.0, cast from DMF/1-propanol (v/v = 3 : 1), relative humidity = 95%). As confirmed by small angle X-ray scattering (SAXS), the side chain block copolymers with tethered ammonium cations showed well-defined lamellar morphologies and a significant reduction in interdomain spacing compared to benzyltrimethyl ammonium containing block copolymers. The chemical stabilities of the block copolymers were evaluated under severe, accelerated conditions, and degradation was observed by (1)H NMR. The block copolymer with C4 side chain trimethyl styrenylbutyl ammonium motifs displayed slightly improved stability compared to that of a benzyltrimethyl ammonium-based AEM at 80 °C in 1 M NaOD aqueous solution for 30 days. PMID:27216558

  18. Group X

    Energy Technology Data Exchange (ETDEWEB)

    Fields, Susannah

    2007-08-16

    This project is currently under contract for research through the Department of Homeland Security until 2011. The group I was responsible for studying has to remain confidential so as not to affect the current project. All dates, reference links and authors, and other distinguishing characteristics of the original group have been removed from this report. All references to the name of this group or the individual splinter groups has been changed to 'Group X'. I have been collecting texts from a variety of sources intended for the use of recruiting and radicalizing members for Group X splinter groups for the purpose of researching the motivation and intent of leaders of those groups and their influence over the likelihood of group radicalization. This work included visiting many Group X websites to find information on splinter group leaders and finding their statements to new and old members. This proved difficult because the splinter groups of Group X are united in beliefs, but differ in public opinion. They are eager to tear each other down, prove their superiority, and yet remain anonymous. After a few weeks of intense searching, a list of eight recruiting texts and eight radicalizing texts from a variety of Group X leaders were compiled.

  19. A Two-Sided, Empirical Model of Television Advertising and Viewing Markets

    OpenAIRE

    Kenneth C. Wilbur

    2008-01-01

    For marketers, television remains the most important advertising medium. This paper proposes a two-sided model of the television industry. We estimate viewer demand for programs on one side and advertiser demand for audiences on the other. The primary objective is to understand how each group's program usage influences the other group. Four main conclusions emerge. First, viewers tend to be averse to advertising. When a highly rated network decreases its advertising time by 10%, our model pre...

  20. Hot Groups.

    Science.gov (United States)

    Vail, Kathleen

    1996-01-01

    Collaborators sparked by creative ideas and obsessed by a common task may not realize they're part of a "hot group"--a term coined by business professors Harold J. Leavitt and Jean Lipman-Blumen. Spawned by group decision making and employee empowerment, hot groups can flourish in education settings. They're typically small, short lived, and goal…

  1. Abelian Groups

    Energy Technology Data Exchange (ETDEWEB)

    Mishina, A.P.

    1995-10-15

    This fifth survey of reviews on abelian groups comprises papers reviewed in 1985-1992. Just as in the preceding surveys, the issues concerning finite abelian groups, topological groups, ordered groups, group algebras, modules (with rare exceptions), and topics on logic are not considered. The issues on the lattice of subgroups of an abelian group are included in Section 11. In contrast to the fourth survey, this one does not contain Sections 6 (N-high subgroups), 9 (rings with a given additive group), and 10 (valuated groups); since only a few papers treated these topics, the material discussed earlier in Sections 9, and 10 is now included in Section 11 and the material of the former Section 6 will be found in Sections 1, 7, 8, and 11 of this survey. On the other hand, the fifth survey has three new sections devoted to separable groups (a new Sect. 5), Butler groups (a new Sect. 6), and the endormorphism rings and automorphism groups of abelian groups (a new Sect. 9).

  2. Group morphology

    NARCIS (Netherlands)

    Roerdink, Jos B.T.M.

    2000-01-01

    In its original form, mathematical morphology is a theory of binary image transformations which are invariant under the group of Euclidean translations. This paper surveys and extends constructions of morphological operators which are invariant under a more general group TT, such as the motion group

  3. Control over molecular motion using the cis–trans photoisomerization of the azo group

    Directory of Open Access Journals (Sweden)

    Estíbaliz Merino

    2012-07-01

    Full Text Available Control over molecular motion represents an important objective in modern chemistry. Aromatic azobenzenes are excellent candidates as molecular switches since they can exist in two forms, namely the cis (Z and trans (E isomers, which can interconvert both photochemically and thermally. This transformation induces a molecular movement and a significant geometric change, therefore the azobenzene unit is an excellent candidate to build dynamic molecular devices. We describe selected examples of systems containing an azobenzene moiety and their motions and geometrical changes caused by external stimuli.

  4. Permutation groups

    CERN Document Server

    Passman, Donald S

    2012-01-01

    This volume by a prominent authority on permutation groups consists of lecture notes that provide a self-contained account of distinct classification theorems. A ready source of frequently quoted but usually inaccessible theorems, it is ideally suited for professional group theorists as well as students with a solid background in modern algebra.The three-part treatment begins with an introductory chapter and advances to an economical development of the tools of basic group theory, including group extensions, transfer theorems, and group representations and characters. The final chapter feature

  5. Galaxy Groups

    Science.gov (United States)

    Tully, R. Brent

    2015-02-01

    Galaxy groups can be characterized by the radius of decoupling from cosmic expansion, the radius of the caustic of second turnaround, and the velocity dispersion of galaxies within this latter radius. These parameters can be a challenge to measure, especially for small groups with few members. In this study, results are gathered pertaining to particularly well-studied groups over four decades in group mass. Scaling relations anticipated from theory are demonstrated and coefficients of the relationships are specified. There is an update of the relationship between light and mass for groups, confirming that groups with mass of a few times {{10}12}{{M}⊙ } are the most lit up while groups with more and less mass are darker. It is demonstrated that there is an interesting one-to-one correlation between the number of dwarf satellites in a group and the group mass. There is the suggestion that small variations in the slope of the luminosity function in groups are caused by the degree of depletion of intermediate luminosity systems rather than variations in the number per unit mass of dwarfs. Finally, returning to the characteristic radii of groups, the ratio of first to second turnaround depends on the dark matter and dark energy content of the universe and a crude estimate can be made from the current observations of {{Ω}matter}˜ 0.15 in a flat topology, with a 68% probability of being less than 0.44.

  6. Galaxy groups

    Energy Technology Data Exchange (ETDEWEB)

    Brent Tully, R. [Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822 (United States)

    2015-02-01

    Galaxy groups can be characterized by the radius of decoupling from cosmic expansion, the radius of the caustic of second turnaround, and the velocity dispersion of galaxies within this latter radius. These parameters can be a challenge to measure, especially for small groups with few members. In this study, results are gathered pertaining to particularly well-studied groups over four decades in group mass. Scaling relations anticipated from theory are demonstrated and coefficients of the relationships are specified. There is an update of the relationship between light and mass for groups, confirming that groups with mass of a few times 10{sup 12}M{sub ⊙} are the most lit up while groups with more and less mass are darker. It is demonstrated that there is an interesting one-to-one correlation between the number of dwarf satellites in a group and the group mass. There is the suggestion that small variations in the slope of the luminosity function in groups are caused by the degree of depletion of intermediate luminosity systems rather than variations in the number per unit mass of dwarfs. Finally, returning to the characteristic radii of groups, the ratio of first to second turnaround depends on the dark matter and dark energy content of the universe and a crude estimate can be made from the current observations of Ω{sub matter}∼0.15 in a flat topology, with a 68% probability of being less than 0.44.

  7. Managing Chemotherapy Side Effects: Hair Loss (Alopecia)

    Science.gov (United States)

    ... C ancer I nstitute Managing Chemotherapy Side Effects Hair Loss (Alopecia) “Losing my hair was hard at first. Then ... and anywhere on your body may fall out. Hair loss is called alopecia. When will my hair start ...

  8. Radiation Therapy: Preventing and Managing Side Effects

    Science.gov (United States)

    ... yourself during radiation therapy Radiation therapy can damage healthy body tissues in or near the area being treated, which can cause side effects. Many people worry about this part of their cancer treatment. Before ...

  9. Side- ja turvanguamet / Indrek Süld

    Index Scriptorium Estoniae

    Süld, Indrek

    2004-01-01

    Ilmunud ka: 2003 : annual report : [Eesti Raudtee]. - Tallinn, 2004, lk. 34-35; 2003 : godovoi ottshjot : [Eesti Raudtee]. - Tallinn, 2004, lk. 34-35. Ülevaade AS-i Eesti Raudtee side- ja turvanguameti tegevusest 2003. aastal. Skeem

  10. Two-sided Heterogeneity and Trade

    OpenAIRE

    Andrew B. Bernard; Moxnes, Andreas; Ulltveit-Moe, Karen Helene

    2013-01-01

    Empirical studies of firms within industries consistently report substantial heterogeneity in measures of performance such as size and productivity. This paper explores the consequences of joint heterogeneity on the supply side (sellers) and the demand side (buyers) in international trade using a novel transaction-level dataset from Norway. Domestic exporters as well as foreign importers are explicitly identified in each transaction to every destination. The buyer-seller linked data reveal a ...

  11. Reliability in Source Coding with Side Information

    OpenAIRE

    Kelly, Benjamin G.; Wagner, Aaron B.

    2011-01-01

    We study error exponents for source coding with side information. Both achievable exponents and converse bounds are obtained for the following two cases: lossless source coding with coded information (SCCSI) and lossy source coding with full side information (Wyner-Ziv). These results recover and extend several existing results on source-coding error exponents and are tight in some circumstances. Our bounds have a natural interpretation as a two-player game between nature and the code designe...

  12. Source Coding with Fixed Lag Side Information

    OpenAIRE

    Martinian, Emin; Wornell, Gregory W.

    2004-01-01

    We consider source coding with fixed lag side information at the decoder. We focus on the special case of perfect side information with unit lag corresponding to source coding with feedforward (the dual of channel coding with feedback) introduced by Pradhan. We use this duality to develop a linear complexity algorithm which achieves the rate-distortion bound for any memoryless finite alphabet source and distortion measure.

  13. Side Stream Filtration for Cooling Towers

    Energy Technology Data Exchange (ETDEWEB)

    None

    2012-10-20

    This technology evaluation assesses side stream filtration options for cooling towers, with an objective to assess key attributes that optimize energy and water savings along with providing information on specific technology and implementation options. This information can be used to assist Federal sites to determine which options may be most appropriate for their applications. This evaluation provides an overview of the characterization of side stream filtration technology, describes typical applications, and details specific types of filtration technology.

  14. Galaxy Groups

    CERN Document Server

    Tully, R Brent

    2014-01-01

    Galaxy groups can be characterized by the radius of decoupling from cosmic expansion, the radius of the caustic of second turnaround, and the velocity dispersion of galaxies within this latter radius. These parameters can be a challenge to measure, especially for small groups with few members. In this study, results are gathered pertaining to particularly well studied groups over four decades in group mass. Scaling relations anticipated from theory are demonstrated and coefficients of the relationships are specified. There is an update of the relationship between light and mass for groups, confirming that groups with mass of a few times 10^12 Msun are the most lit up while groups with more and less mass are darker. It is demonstrated that there is an interesting one-to-one correlation between the number of dwarf satellites in a group and the group mass. There is the suggestion that small variations in the slope of the luminosity function in groups are caused by the degree of depletion of intermediate luminosi...

  15. Energy perspectives 2035 - Volume 4, side-notes

    International Nuclear Information System (INIS)

    This comprehensive report published by the Swiss Federal Office of Energy (SFOE) presents a number of side-notes pertaining to the first three volumes of the Energy Perspectives series of reports. Various topics are discussed by the authors of the first three volumes of the perspectives in the meetings held by the Energy Perspectives Working Group. The sixteen side-notes presented here cover the following topics: General conditions, fossil resources, the influence of climate warming, CO2 emissions trading (Joint Implementation JI and Clean Development Mechanism CDM), definition of potentials, air traffic, imported renewable electricity, hydro power, electricity cost calculation, sensitivity analysis of centralised power production facilities, heat-pumps and their power consumption, cold spells and heat-waves, risk and its perception, the 2000-Watt society and international and national energy perspectives

  16. Nonlinear time series analysis of knee and ankle kinematics during side by side treadmill walking

    Science.gov (United States)

    Nessler, Jeff A.; De Leone, Charles J.; Gilliland, Sara

    2009-06-01

    Nonlinear time series analysis was used to estimate maximal Lyapunov exponents of select ankle and knee kinematics during three different conditions of treadmill walking: independent, side by side, and side by side with forced synchronization of stepping. Stride to stride variability was significantly increased for the condition in which individuals walked side by side and synchronized unintentionally when compared to the conditions of forced synchronization and independent walking. In addition, standard deviations of three kinematic variables of lower extremity movement were significantly increased during the condition in which unintentional synchronization occurred. No relationship was found between standard deviation and estimates of maximal Lyapunov exponents. An increase in kinematic variability during side by side walking for nonimpaired individuals who are not at risk of falling suggests that variability in certain aspects of performance might be indicative of a healthy system. Modeling this variability for an impaired individual to imitate may have beneficial effects on locomotor function. These results may therefore have implications for the rehabilitation of gait in humans by suggesting that a different functional outcome might be achieved by practicing side by side walking as opposed to more commonly used strategies involving independent walking.

  17. Hematological Side Effects of Atypical Antipsychotic Drugs

    Directory of Open Access Journals (Sweden)

    Serap Erdogan

    2009-10-01

    Full Text Available Atypical antipsychotics cause less frequently extrapyramidal system symptoms, neuroleptic malignant syndrome and hyperprolactinemia than typical antipsychotics. However hematological side effects such as leukopenia and neutropenia could occur during treatment with atypical antipsychotics. These side effects could lead to life threatening situations and the mortality rate due to drug related agranulocytosis is about 5-10%. There are several hypothesis describing the mechanisms underlying drug induced leukopenia and/or neutropenia such as direct toxic effects of these drugs upon the bone marrow or myeloid precursors, immunologic destruction of the granulocytes or supression of the granulopoiesis. Clozapine is the antipsychotic agent which has been most commonly associated with agranulocytosis. A nitrenium ion which is formed by the bioactivation of clozapine is thought to have an important role in the pathophysiogy of this adverse effect. Aside from clozapine, there are several case reports reporting an association between olanzapine, quetiapine, risperidone, ziprasidone, aripiprazole and leukopenia. We did not find any study or case report presenting amisulpride or sulpride related hematological side effects in our literature search. Patients who had hematological side effects during their previous antipsychotic drug treatments and who had lower baseline blood leukocyte counts, have higher risk to develop leukopenia or neutropenia during their current antipsychotic treatment. Once leukopenia and neutropenia develops, drugs thought to be responsible for this side effect should be discontinued or dosages should be lowered. In some cases iniatition of lithium or G-CSF (granulocyte colony-stimulating factor therapy may be helpful in normalizing blood cell counts. Clinicans should avoid any combination of drugs known to cause hematological side effects. Besides during antipsychotic treatment, infection symptoms such as fever, cough, sore throat or

  18. Temporomandibular disorders: the habitual chewing side syndrome.

    Directory of Open Access Journals (Sweden)

    Urbano Santana-Mora

    Full Text Available BACKGROUND: Temporomandibular disorders are the most common cause of chronic orofacial pain, but, except where they occur subsequent to trauma, their cause remains unknown. This cross-sectional study assessed chewing function (habitual chewing side and the differences of the chewing side and condylar path and lateral anterior guidance angles in participants with chronic unilateral temporomandibular disorder. This is the preliminary report of a randomized trial that aimed to test the effect of a new occlusal adjustment therapy. METHODS: The masticatory function of 21 randomly selected completely dentate participants with chronic temporomandibular disorders (all but one with unilateral symptoms was assessed by observing them eat almonds, inspecting the lateral horizontal movement of the jaw, with kinesiography, and by means of interview. The condylar path in the sagittal plane and the lateral anterior guidance angles with respect to the Frankfort horizontal plane in the frontal plane were measured on both sides in each individual. RESULTS: Sixteen of 20 participants with unilateral symptoms chewed on the affected side; the concordance (Fisher's exact test, P = .003 and the concordance-symmetry level (Kappa coefficient κ = 0.689; 95% confidence interval [CI], 0.38 to 0.99; P = .002 were significant. The mean condylar path angle was steeper (53.47(10.88 degrees versus 46.16(7.25 degrees; P = .001, and the mean lateral anterior guidance angle was flatter (41.63(13.35 degrees versus 48.32(9.53 degrees P = .036 on the symptomatic side. DISCUSSION: The results of this study support the use of a new term based on etiology, "habitual chewing side syndrome", instead of the nonspecific symptom-based "temporomandibular joint disorders"; this denomination is characterized in adults by a steeper condylar path, flatter lateral anterior guidance, and habitual chewing on the symptomatic side.

  19. Hydra groups

    CERN Document Server

    Dison, Will

    2010-01-01

    We give examples of CAT(0), biautomatic, free-by-cyclic, one-relator groups which have finite-rank free subgroups of huge (Ackermannian) distortion. This leads to elementary examples of groups whose Dehn functions are similarly extravagant. This behaviour originates in manifestations of Hercules-versus-the-hydra battles in string-rewriting.

  20. [Selected aspects of oral contraception side effects].

    Science.gov (United States)

    Wolski, Hubert

    2014-12-01

    The first hormonal pill was approved in the 60s of the twentieth century Since that time, oral contraception has been used worldwide by dozens of women due to its high availability as well as relative ease and safety of taking. The main side effects of oral contraception include elevated risk for venous thromboembolism (VTE). Estrogens increase the probability of VTE development, depending on the dose in medication, and third-generation progestins increase the risk of VTE development more than older-generation progestins. Also, the coexistence of hereditary thrombophilia increases the risk of VTE development in women using oral contraceptives. Other side effects include changes in the carbohydrate and lipid economy Progestins in oral contraceptives decrease HDL cholesterol levels but increase LDL cholesterol and total cholesterol levels. Additionally estrogens are a recognized mitogenic factor for the epithelium of the mammary gland, acting proliferative on the glandular tissue and in the same way influence on the increased risk of breast cancer development. Patients sometimes complain about some subjective side symptoms such as headache, mood changes, nausea, back pain, breast pain and swelling, as well as decreased libido. Some patients discontinue oral contraception due to fear of side effects or temporary ailments before con- sulting their doctor what may result in unintended pregnancy The aim of the following paper was to present most frequent side effects of oral contraception, ways of their moni- toring and diagnosis. PMID:25669065

  1. The DarkSide-50 outer detectors

    Science.gov (United States)

    Westerdale, S.; Agnes, P.; Agostino, L.; Albuquerque, I. F. M.; Alexander, T.; Alton, A. K.; Arisaka, K.; Back, H. O.; Baldin, B.; Biery, K.; Bonfini, G.; Bossa, M.; Bottino, B.; Brigatti, A.; Brodsky, J.; Budano, F.; Bussino, S.; Cadeddu, M.; Cadonati, L.; Cadoni, M.; Calaprice, F.; Canci, N.; Candela, A.; Cao, H.; Cariello, M.; Carlini, M.; Catalanotti, S.; Cavalcante, P.; Chepurnov, A.; Cocco, A. G.; Covone, G.; D’Angelo, D.; D’Incecco, M.; Davini, S.; De Cecco, S.; De Deo, M.; De Vincenzi, M.; Derbin, A.; Devoto, A.; Di Eusanio, F.; Di Pietro, G.; Edkins, E.; Empl, A.; Fan, A.; Fiorillo, G.; Fomenko, K.; Foster, G.; Franco, D.; Gabriele, F.; Galbiati, C.; Giganti, C.; Goretti, A. M.; Granato, F.; Grandi, L.; Gromov, M.; Guan, M.; Guardincerri, Y.; Hackett, B. R.; Herner, K. R.; Hungerford, E. V.; Aldo, Ianni; Andrea, Ianni; James, I.; Jollet, C.; Keeter, K.; Kendziora, C. L.; Kobychev, V.; Koh, G.; Korablev, D.; Korga, G.; Kubankin, A.; Li, X.; Lissia, M.; Lombardi, P.; Luitz, S.; Ma, Y.; Machulin, I. N.; Mandarano, A.; Mari, S. M.; Maricic, J.; Marini, L.; Martoff, C. J.; Meregaglia, A.; Meyers, P. D.; Miletic, T.; Milincic, R.; Montanari, D.; Monte, A.; Montuschi, M.; Monzani, M. E.; Mosteiro, P.; Mount, B. J.; Muratova, V. N.; Musico, P.; Napolitano, J.; Orsini, M.; Ortica, F.; Pagani, L.; Pallavicini, M.; Pantic, E.; Parmeggiano, S.; Pelczar, K.; Pelliccia, N.; Perasso, S.; Pocar, A.; Pordes, S.; Pugachev, D. A.; Qian, H.; Randle, K.; Ranucci, G.; Razeto, A.; Reinhold, B.; Renshaw, A. L.; Romani, A.; Rossi, B.; Rossi, N.; Rountree, S. D.; Sablone, D.; Saggese, P.; Saldanha, R.; Sands, W.; Sangiorgio, S.; Savarese, C.; Segreto, E.; Semenov, D. A.; Shields, E.; Singh, P. N.; DSkorokhvatov, M.; Smirnov, O.; Sotnikov, A.; Stanford, C.; Suvorov, Y.; Tartaglia, R.; Tatarowicz, J.; Testera, G.; Tonazzo, A.; Trinchese, P.; Unzhakov, E. V.; Vishneva, A.; Vogelaar, B.; Wada, M.; Walker, S.; Wang, H.; Wang, Y.; Watson, A. W.; Wilhelmi, J.; Wojcik, M. M.; Xiang, X.; Xu, J.; Yang, C.; Yoo, J.; Zavatarelli, S.; Zec, A.; Zhong, W.; Zhu, C.; Zuzel, G.; The DarkSide Collaboration

    2016-05-01

    DarkSide-50 is a dark matter detection experiment searching for Weakly Interacting Massive Particles (WIMPs), in Gran Sasso National Laboratory. For experiments like DarkSide-50, neutrons are one of the primary backgrounds that can mimic WIMP signals. The experiment consists of three nested detectors: a liquid argon time projection chamber surrounded by two outer detectors. The outermost detector is a 10 m by 11 m cylindrical water Cherenkov detector with 80 PMTs, designed to provide shielding and muon vetoing. Inside the water Cherenkov detector is the 4 m diameter spherical boron-loaded liquid scintillator veto, with a cocktail of pseudocumene, trimethyl borate, and PPO wavelength shifter, designed to provide shielding, neutron vetoing, and in situ measurements of the TPC backgrounds. We present design and performance details of the DarkSide-50 outer detectors.

  2. Communication technologies for demand side management

    Energy Technology Data Exchange (ETDEWEB)

    Uuspaeae, P. [VTT Energy, Espoo (Finland)

    1998-08-01

    The scope of this research is data communications for electric utilities, specifically for the purposes of Demand Side Management (DSM). Demand Side Management has the objective to change the customer`s end use of energy in a manner that benefits both the customer and the utility. For example, peak demand may be reduced, and the peak demand may be relocated to off peak periods. Thus additional investments in generation and network may be avoided. A number of Demand Side Management functions can be implemented if a communication system is available between the Electric Utility and the Customer. The total communication capacity that is needed, will depend on several factors, such as the functions that are chosen for DSM, and on the number and type of customers. Some functions may be handled with one-way communications, while some other functions need to have two-way communication

  3. One-sided flux of fermions

    International Nuclear Information System (INIS)

    In the one-body window-friction pricture for inelastic heavy-ion collisions the one-sided flux of nucleons passing the window in the mean potential plays the role of the frictional form factor. In this paper a quantum mechanical operator for the one-sided flux is defined. Its expectation value calculated with any given many-body wave function yields the number of particles crossing an area element dA vector per unit time in one direction. The quantum one-sided flux is compared to the classical one calculated with a uniform momentum distribution up to the Fermi momentum. The wave function was taken from a model calculation for a fermion gas in a one-dimensional box. 1 figure

  4. Areeda-turner in two-sided markets

    NARCIS (Netherlands)

    Behringer, S.; Filistrucchi, L.

    2015-01-01

    We extend the Areeda–Turner rule to two-sided markets. We show that a two-sided monopolist may find it short-run profit-maximizing to charge a price below marginal cost on one side of the market. Hence showing that the price is below marginal cost on one side of a two-sided market cannot be consider

  5. Group Grammar

    Science.gov (United States)

    Adams, Karen

    2015-01-01

    In this article Karen Adams demonstrates how to incorporate group grammar techniques into a classroom activity. In the activity, students practice using the target grammar to do something they naturally enjoy: learning about each other.

  6. MUYANG GROUP

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    @@ With its headquarters in the historic city of Yangzhou,Jiangsu Muyang Group Co.,Ltd has since its founding in 1967 grown into a well-known group corporation whose activities cover research&development.project design,manufacturing,installation and services in a multitude of industries including feed machinery and engineering,storage engineering,grain machinery and engineering,environmental protection,conveying equipment and automatic control systems.

  7. Abelian groups

    CERN Document Server

    Fuchs, László

    2015-01-01

    Written by one of the subject’s foremost experts, this book focuses on the central developments and modern methods of the advanced theory of abelian groups, while remaining accessible, as an introduction and reference, to the non-specialist. It provides a coherent source for results scattered throughout the research literature with lots of new proofs. The presentation highlights major trends that have radically changed the modern character of the subject, in particular, the use of homological methods in the structure theory of various classes of abelian groups, and the use of advanced set-theoretical methods in the study of undecidability problems. The treatment of the latter trend includes Shelah’s seminal work on the undecidability in ZFC of Whitehead’s Problem; while the treatment of the former trend includes an extensive (but non-exhaustive) study of p-groups, torsion-free groups, mixed groups, and important classes of groups arising from ring theory. To prepare the reader to tackle these topics, th...

  8. Update on side effects from common vaccines.

    Science.gov (United States)

    Song, Benjamin J; Katial, Rohit K

    2004-11-01

    Vaccines have had a tremendous impact on public health by reducing morbidity and mortality from a variety of virulent pathogens. However, unintended side effects continue to pose a potential risk that may outweigh the vaccine's protective attributes. In this review, we discuss recent articles and controversies pertaining to vaccine-associated adverse events. Included in the discussion are influenza, hepatitis B, measles-mumps-rubella, diphtheria-tetanus-pertussis, polio, Haemophilus influenzae type b, and rotavirus vaccines. The importance and contribution of vaccine constituents (such as thimerosal) to side effects is also reviewed.

  9. Server-side Statistics Scripting in PHP

    OpenAIRE

    Jan de Leeuw

    1997-01-01

    On the UCLA Statistics WWW server there are a large number of demos and calculators that can be used in statistics teaching and research. Some of these demos require substantial amounts of computation, others mainly use graphics. These calculators and demos are implemented in various different ways, reflecting developments in WWW based computing. As usual, one of the main choices is between doing the work on the client-side (i.e. in the browser) or on the server-side (i.e. on our WWW ser...

  10. Demand side integration aspects in active distribution planning

    DEFF Research Database (Denmark)

    Silvestro, Federico; Baitch, Alex; Pilo, Fabrizio;

    2013-01-01

    will be implemented in practice? How will regulatory frameworks and connection agreements evolve to support ADSs? The present work provides some information about the closer and closer integration between network planning and Demand Side Integration that is foreseen in the future and shows the......This paper presents an overview of the activities of CIGRE Working Group WG C6.19 (WG), focusing on the planning and optimization of active distribution systems. A key challenge in planning Active Distribution Systems (ADSs) is the uncertainty of the future, i.e., what level of active management...

  11. Group dynamics.

    Science.gov (United States)

    Scandiffio, A L

    1990-12-01

    Group dynamics play a significant role within any organization, culture, or unit. The important thing to remember with any of these structures is that they are made up of people--people with different ideas, motivations, background, and sometimes different agendas. Most groups, formal or informal, look for a leader in an effort to maintain cohesiveness of the unit. At times, that cultural bond must be developed; once developed, it must be nurtured. There are also times that one of the group no longer finds the culture comfortable and begins to act out behaviorally. It is these times that become trying for the leader as she or he attempts to remain objective when that which was once in the building phase of group cohesiveness starts to fall apart. At all times, the manager must continue to view the employee creating the disturbance as an integral part of the group. It is at this time that it is beneficial to perceive the employee exhibiting problem behaviors as a special employee, as one who needs the benefit of your experience and skills, as one who is still part of the group. It is also during this time that the manager should focus upon her or his own views in the area of power, communication, and the corporate culture of the unit that one has established before attempting to understand another's point of view. Once we understand our own motivation and accept ourselves, it is then that we may move on to offer assistance to another. Once we understand our insecurities recognizing staff dysfunction as a symptom of system dysfunction will not be so threatening to the concept of the manager that we perceive ourselves to be. It takes a secure person to admit that she or he favors staff before deciding to do something to change things. The important thing to know is that it can be done. The favored staff can find a new way of relating to others, the special employee can find new modes of behavior (and even find self-esteem in the process), the group can find new ways

  12. Group dynamics.

    Science.gov (United States)

    Scandiffio, A L

    1990-12-01

    Group dynamics play a significant role within any organization, culture, or unit. The important thing to remember with any of these structures is that they are made up of people--people with different ideas, motivations, background, and sometimes different agendas. Most groups, formal or informal, look for a leader in an effort to maintain cohesiveness of the unit. At times, that cultural bond must be developed; once developed, it must be nurtured. There are also times that one of the group no longer finds the culture comfortable and begins to act out behaviorally. It is these times that become trying for the leader as she or he attempts to remain objective when that which was once in the building phase of group cohesiveness starts to fall apart. At all times, the manager must continue to view the employee creating the disturbance as an integral part of the group. It is at this time that it is beneficial to perceive the employee exhibiting problem behaviors as a special employee, as one who needs the benefit of your experience and skills, as one who is still part of the group. It is also during this time that the manager should focus upon her or his own views in the area of power, communication, and the corporate culture of the unit that one has established before attempting to understand another's point of view. Once we understand our own motivation and accept ourselves, it is then that we may move on to offer assistance to another. Once we understand our insecurities recognizing staff dysfunction as a symptom of system dysfunction will not be so threatening to the concept of the manager that we perceive ourselves to be. It takes a secure person to admit that she or he favors staff before deciding to do something to change things. The important thing to know is that it can be done. The favored staff can find a new way of relating to others, the special employee can find new modes of behavior (and even find self-esteem in the process), the group can find new ways

  13. Water Quality Performance of Three Side-by-Side Permeable Pavement Surface Materials: Three Year Update

    Science.gov (United States)

    Communities are increasingly installing structural low impact development (LID) practices to mange stormwater and reduce pollutant loads associated with stormwater runoff. Permeable pavement is a LID practice that has limited research on working-scale, side-by-side performance o...

  14. Illinois Early Childhood Program Standards Matrix. (A Side-by-Side Comparison).

    Science.gov (United States)

    Illinois State Dept. of Human Services, East St. Louis. Head Start State Collaboration Office.

    This document contains a matrix offering a side-by-side comparison of almost 40 criteria among 7 sets of early childhood program standards. The standards are: (1) Head Start Program Performance Standards; (2) Illinois Department of Children and Family Services Child Care Licensing Standards; (3) Illinois Department of Human Services (IDHS) Center…

  15. Functionally Graded Ceramics Fabricated with Side-by-Side Tape Casting for Use in Magnetic Refrigeration

    DEFF Research Database (Denmark)

    Bulatova, Regina; Bahl, Christian; Andersen, Kjeld Bøhm;

    2015-01-01

    Functionally graded ceramic tapes have been fabricated by a side-by-side tape casting technique. This study shows the possibility and describes the main principles of adjacent coflow of slurries resulting in formation of thin plates of graded ceramic material. Results showed that the small variat...

  16. EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Ai ds (CEF); Scientific Opinion on Flavouring Group Evaluation 208 (FGE.208): Consideration of genotoxicity data on representatives for 10 alicyclic aldehydes with the α , β - unsaturation in ring / side - chain

    DEFF Research Database (Denmark)

    Beltoft, Vibe Meister; Binderup, Mona-Lise; Lund, Pia;

    The Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids of the European Food Safety Authority was requested to evaluate the genotoxic potential of one flavouring substance from subgroup 2.2 of FGE.19 in the Flavouring Group Evaluation 208. The Flavour Industry has provided....... In order to clarify the genotoxic potential of this substance, the Panel considered that further in vivo testing should be performed. To address this, an in vivo Comet assay, considering the first site of contact (e.g. stomach or duodenum) and liver, should be carried out according to the Scientific Report...

  17. A Numerical Study of Some Potential Sources of Error in Side-by-Side Seismometer Evaluations

    Science.gov (United States)

    Holcomb, L. Gary

    1990-01-01

    INTRODUCTION This report presents the results of a series of computer simulations of potential errors in test data, which might be obtained when conducting side-by-side comparisons of seismometers. These results can be used as guides in estimating potential sources and magnitudes of errors one might expect when analyzing real test data. First, the derivation of a direct method for calculating the noise levels of two sensors in a side-by-side evaluation is repeated and extended slightly herein. This bulk of this derivation was presented previously (see Holcomb 1989); it is repeated here for easy reference. This method is applied to the analysis of a simulated test of two sensors in a side-by-side test in which the outputs of both sensors consist of white noise spectra with known signal-to-noise ratios (SNR's). This report extends this analysis to high SNR's to determine the limitations of the direct method for calculating the noise levels at signal-to-noise levels which are much higher than presented previously (see Holcomb 1989). Next, the method is used to analyze a simulated test of two sensors in a side-by-side test in which the outputs of both sensors consist of bandshaped noise spectra with known signal-to-noise ratios. This is a much more realistic representation of real world data because the earth's background spectrum is certainly not flat. Finally, the results of the analysis of simulated white and bandshaped side-by-side test data are used to assist in interpreting the analysis of the effects of simulated azimuthal misalignment in side-by-side sensor evaluations. A thorough understanding of azimuthal misalignment errors is important because of the physical impossibility of perfectly aligning two sensors in a real world situation. The analysis herein indicates that alignment errors place lower limits on the levels of system noise which can be resolved in a side-by-side measurement. It also indicates that alignment errors are the source of the fact that

  18. Splenic fibrosis and sarcomas in F344 rats fed diets containing aniline hydrochloride, p-chloroaniline, azobenzene, o-toluidine hydrochloride, 4,4'-sulfonyldianiline, or D & C red No. 9.

    Science.gov (United States)

    Goodman, D G; Ward, J M; Reichardt, W D

    1984-07-01

    In six carcinogenicity bioassays, male and female F344 rats were fed diets containing aniline hydrochloride (CAS: 142-04-1; hydrochloride benzenamide), p-chloroaniline (CAS: 106-47-8), azobenzene (CAS: 103-33-3), o-toluidine hydrochloride (CAS: 636-21-5), dapsone (CAS: 80-08-0; 4,4'-sulfonyldianiline), or D & C red No. 9 [CAS: D85500000; 5-chloro-2-[2-hydroxy-1-naphthalenyl)azo)-4-methylbenzenesulfon ic acid, barium salt]. The rats, from 6 weeks to 2 years old, were given the compounds at two dose levels, the estimated maximum tolerated dose and one-half that dose. In all six bioassays, dose-dependent incidences of splenic sarcomas and fibrosis were seen, with the highest incidences in male rats. Fibrosis occurred in the splenic parenchyma and/or the capsule. Fatty infiltration also was seen in the spleen. Sarcomas appeared to arise in the splenic red pulp or splenic capsule, usually in association with areas of parenchymal and capsular fibrosis and pigmentation. Larger tumors metastasized to the peritoneal cavity and abdominal organs. In some rats there was marked osseous metaplasia when the primary tumor metastasized to peritoneal surfaces. Other, less common, splenic neoplasms included hemangiosarcoma and hemangiopericytoma. Some rats had such extensive peritoneal involvement that the site of origin of their sarcoma was difficult to determine.

  19. Splenic fibrosis and sarcomas in F344 rats fed diets containing aniline hydrochloride, p-chloroaniline, azobenzene, o-toluidine hydrochloride, 4,4'-sulfonyldianiline, or D & C red No. 9.

    Science.gov (United States)

    Goodman, D G; Ward, J M; Reichardt, W D

    1984-07-01

    In six carcinogenicity bioassays, male and female F344 rats were fed diets containing aniline hydrochloride (CAS: 142-04-1; hydrochloride benzenamide), p-chloroaniline (CAS: 106-47-8), azobenzene (CAS: 103-33-3), o-toluidine hydrochloride (CAS: 636-21-5), dapsone (CAS: 80-08-0; 4,4'-sulfonyldianiline), or D & C red No. 9 [CAS: D85500000; 5-chloro-2-[2-hydroxy-1-naphthalenyl)azo)-4-methylbenzenesulfon ic acid, barium salt]. The rats, from 6 weeks to 2 years old, were given the compounds at two dose levels, the estimated maximum tolerated dose and one-half that dose. In all six bioassays, dose-dependent incidences of splenic sarcomas and fibrosis were seen, with the highest incidences in male rats. Fibrosis occurred in the splenic parenchyma and/or the capsule. Fatty infiltration also was seen in the spleen. Sarcomas appeared to arise in the splenic red pulp or splenic capsule, usually in association with areas of parenchymal and capsular fibrosis and pigmentation. Larger tumors metastasized to the peritoneal cavity and abdominal organs. In some rats there was marked osseous metaplasia when the primary tumor metastasized to peritoneal surfaces. Other, less common, splenic neoplasms included hemangiosarcoma and hemangiopericytoma. Some rats had such extensive peritoneal involvement that the site of origin of their sarcoma was difficult to determine. PMID:6588231

  20. Synthesis and characterization of organic nanoparticles based on azobenzene small molecule%偶氮苯类有机小分子纳米粒子的制备及表征

    Institute of Scientific and Technical Information of China (English)

    王静; 顾维闰; 郑海洋; 沈达; 田小燕

    2011-01-01

    以十六烷基三甲基溴化铵(CTAB)为稳定剂和模板,利用再沉淀法制备了偶氮苯类有机小分子2-(4-羟基苯基-偶氮)苯甲酸(HABA)的纳米粒子,并用紫外—可见吸收光谱(UV-vis)、扫描电镜(SEM)和圆二色谱(CD)等测试手段对其进行了表征.结果表明:制备的HABA纳米粒子为带状,在无手性诱导剂条件下制备的纳米粒子表现出了超分子手性.%Based on azobenzene small molecule 2-(4-hydraphenyl-azo) benzoic acid (HABA) , organic nanop-articles are prepared by reprecipitation method when cetyltrimethylammonium bromide (CTAB) as a stabilizer and template. The as-prepared nanoparticles are characterized by UV-vis Spectrometer (UV-vis) , Scanning Electron Microscope (SEM) and Circular Dichroism spectrometer (CD). The results reveal that the prepared HABA nanoparticles have regular ribbon-like shape and show supramolecular chirality in absence of chiral inducer.

  1. Protection of the side of the head.

    Science.gov (United States)

    Gilchrist, A; Mills, N J

    1996-07-01

    The side of the head is a frequent impact site for pedal cyclists, motorcyclists, and industrial workers. It is vulnerable to impact, yet many helmet standards do not have impact tests at the side of the helmet. Laboratory impact tests should reproduce the phenomena in real impacts, but usually they do not allow the headform to rotate, or ignore the effect of the neck on the motion of the head. The authors designed a linkage, simulating the flexibility of the neck, for use with anthropomorphic dummies in helmet testing. Impacts at the side of the helmet, normal to the helmet surface, were made with flat and hemispherical strikers. Head rotation during impacts caused the impact site to move, in some cases to below the level protected by the helmet. The peak angular head acceleration correlated with the peak linear accelerations. Neck flexibility means that helmets can protect the head from higher kinetic energy impacts than those specified in standards using immovable headforms or impact anvils. The load spreading efficiency of polypropylene foam, used in soft shell bicycle helmets, is better than that of polystyrene foam. The authors conclude that the side of the head can be protected by a suitable helmet design.

  2. Neglected Side Effects After Radical Prostatectomy

    DEFF Research Database (Denmark)

    Frey, Anders Ullmann; Sønksen, Jens; Fode, Mikkel

    2014-01-01

    INTRODUCTION: A series of previously neglected sexually related side effects to radical prostatectomy (RP) has been identified over the recent years. These include orgasm-associated incontinence (OAI), urinary incontinence in relation to sexual stimulation (UISS), altered perception of orgasm, or...

  3. Struck by a lance through his side

    DEFF Research Database (Denmark)

    Leth, Peter Mygind; Boldsen, Jesper Lier

    2010-01-01

    The Danish King Canute the Saint was killed in St Alban church in Odense July 1086. According to a legend the king was kneeling in prayers when a lance thrust to his side killed him. Our re-examination of the skeleton presumed to belong to Canute showed a slimly build man with an approximate...

  4. On one-sided torsion pair

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Motivated by the concept of a torsion pair in a pre-triangulated category induced by Beligiannis and Reiten, the notion of a left (right) torsion pair in the left (right) triangulated category is introduced and investigated. We provide new connections between different aspects of torsion pairs in one-sided triangulated categories, pre-triangulated categories, stable categories and derived categories.

  5. Solar cell with back side contacts

    Energy Technology Data Exchange (ETDEWEB)

    Nielson, Gregory N; Okandan, Murat; Cruz-Campa, Jose Luis; Resnick, Paul J; Wanlass, Mark Woodbury; Clews, Peggy J

    2013-12-24

    A III-V solar cell is described herein that includes all back side contacts. Additionally, the positive and negative electrical contacts contact compoud semiconductor layers of the solar cell other than the absorbing layer of the solar cell. That is, the positive and negative electrical contacts contact passivating layers of the solar cell.

  6. Regional renal venous hypertension and left-sided varicocele

    Directory of Open Access Journals (Sweden)

    O. B. Zhukov

    2013-01-01

    Full Text Available One of the most frequent correctable causes of male infertility is a varicocele. The etiology and pathogenesis of varicocele to date is a matter of debate. The aim of our study was to determine the causes and incidence of regional renal hypertension in patients with leftsided varicocele. The study involved 110 patients with left-sided varicocele in age from 18 to 35 years. Algorithm for evaluation of patients with left-sided varicocele included: physical examination, ultrasound with Doppler kidney, basin area left renal vein, aorto-mesenteric portion; the scrotum with a sample Trombetta, phlebography аnd phlebotonometry basin left renal vein and the common iliac vein. Renospermatic reflux was detected in 89 (81 %, ileospermatic 12 (11 % and mixed 9 (8 % patients. Patients with reflux ileospermatic excluded from the study. The 96 patients with left-sided varicocele underwent venography and phlebotonometry in 37 (38.5 % were renal venous hypertension, with 35 of them that it was due to aorto-mesenteric compression, and in 2 cases an anomaly development – annular renal vein. Our data are comparable with the results of other authors. Patients with mesenteric compressed statistically significant reduction in the diameter of renal veins in the aorto-mesenteric portion and increased blood flow in this region, and expand prestenosis left renal vein and reduce flow velocity in this region compared with the group without renal phlebohypertension. Patients with renal phlebohypertension subsequently held shunt types of operations performed in patients with normotension occlusive types of operations. An integrated assessment of patients with left-side allows to make a holistic understanding of the basic mechanisms of disease etiology and select the appropriate type of surgery.

  7. Regional renal venous hypertension and left-sided varicocele

    Directory of Open Access Journals (Sweden)

    O. B. Zhukov

    2014-11-01

    Full Text Available One of the most frequent correctable causes of male infertility is a varicocele. The etiology and pathogenesis of varicocele to date is a matter of debate. The aim of our study was to determine the causes and incidence of regional renal hypertension in patients with leftsided varicocele. The study involved 110 patients with left-sided varicocele in age from 18 to 35 years. Algorithm for evaluation of patients with left-sided varicocele included: physical examination, ultrasound with Doppler kidney, basin area left renal vein, aorto-mesenteric portion; the scrotum with a sample Trombetta, phlebography аnd phlebotonometry basin left renal vein and the common iliac vein. Renospermatic reflux was detected in 89 (81 %, ileospermatic 12 (11 % and mixed 9 (8 % patients. Patients with reflux ileospermatic excluded from the study. The 96 patients with left-sided varicocele underwent venography and phlebotonometry in 37 (38.5 % were renal venous hypertension, with 35 of them that it was due to aorto-mesenteric compression, and in 2 cases an anomaly development – annular renal vein. Our data are comparable with the results of other authors. Patients with mesenteric compressed statistically significant reduction in the diameter of renal veins in the aorto-mesenteric portion and increased blood flow in this region, and expand prestenosis left renal vein and reduce flow velocity in this region compared with the group without renal phlebohypertension. Patients with renal phlebohypertension subsequently held shunt types of operations performed in patients with normotension occlusive types of operations. An integrated assessment of patients with left-side allows to make a holistic understanding of the basic mechanisms of disease etiology and select the appropriate type of surgery.

  8. Group Anonymity

    CERN Document Server

    Chertov, Oleg; 10.1007/978-3-642-14058-7_61

    2010-01-01

    In recent years the amount of digital data in the world has risen immensely. But, the more information exists, the greater is the possibility of its unwanted disclosure. Thus, the data privacy protection has become a pressing problem of the present time. The task of individual privacy-preserving is being thoroughly studied nowadays. At the same time, the problem of statistical disclosure control for collective (or group) data is still open. In this paper we propose an effective and relatively simple (wavelet-based) way to provide group anonymity in collective data. We also provide a real-life example to illustrate the method.

  9. Lego Group

    DEFF Research Database (Denmark)

    Møller Larsen, Marcus; Pedersen, Torben; Slepniov, Dmitrij

    2010-01-01

    The last years’ rather adventurous journey from 2004 to 2009 had taught the fifth-largest toy-maker in the world - the LEGO Group - the importance of managing the global supply chain effectively. In order to survive the largest internal financial crisis in its roughly 70 years of existence......, the management had, among many initiatives, decided to offshore and outsource a major chunk of its production to Flextronics. In this pursuit of rapid cost-cutting sourcing advantages, the LEGO Group planned to license out as much as 80 per cent of its production besides closing down major parts...

  10. The Social Side Effects of Acetaminophen

    Science.gov (United States)

    Mischkowski, Dominik

    About 23% of all adults in the US take acetaminophen during an average week (Kaufman, Kelly, Rosenberg, Anderson, & Mitchell, 2002) because acetaminophen is an effective physical painkiller and easily accessible over the counter. The physiological side effects of acetaminophen are well documented and generally mild when acetaminophen is consumed in the appropriate dosage. In contrast, the psychological and social side effects of acetaminophen are largely unknown. Recent functional neuroimaging research suggests that the experience of physical pain is fundamentally related to the experience of empathy for the pain of other people, indicating that pharmacologically reducing responsiveness to physical pain also reduces cognitive, affective, and behavioral responsiveness to the pain of others. I tested this hypothesis across three double-blind between-subjects drug intervention studies. Two experiments showed that acetaminophen had moderate effects on empathic affect, specifically personal distress and empathic concern, and a small effect on empathic cognition, specifically perceived pain, when facing physical and social pain of others. The same two experiments and a third experiment also showed that acetaminophen can increase the willingness to inflict pain on other people, i.e., actual aggressive behavior. This effect was especially pronounced among people low in dispositional empathic concern. Together, these findings suggest that the physical pain system is more involved in the regulation of social cognition, affect, and behavior than previously assumed and that the experience of physical pain and responsiveness to the pain of others share a common neurochemical basis. Furthermore, these findings suggest that acetaminophen has unappreciated but serious social side effects, and that these side effects may depend on psychological characteristics of the drug consumer. This idea is consistent with recent theory and research on the context-dependency of neurochemical

  11. Chewing side, bite force symmetry, and occlusal contact area of subjects with different facial vertical patterns

    OpenAIRE

    Simone Guimarães Farias Gomes; William Custodio; Fernanda Faot; Altair Antoninha Del Bel Cury; Renata Cunha Matheus Rodrigues Garcia

    2011-01-01

    Craniofacial dimensions influence oral functions; however, it is not known whether they are associated with function asymmetry. The objective of this study was to evaluate chewing side preference and lateral asymmetry of occlusal contact area and bite force of individuals with different craniofacial patterns. Seventy-eight dentate subjects were divided into 3 groups according to the VERT index as follows: (1) mesofacial, (2) brachyfacial and (3) dolichofacial. Chewing side preference was eval...

  12. Suggestion and verification of compensatory exercise for one {--} sidedly oriented sportsman to prevent muscle dysbalance

    OpenAIRE

    AMBROZOVÁ, Markéta

    2009-01-01

    Graduation theses solve the suggestion and verification of compensatory exercise for one {--} sidedly oriented sportsman. Tested group is tennis-players from Teniscentrum Příbram. By the influence of one {--} sidedly oriented movement can form functional and structural fault motoric systém of muscle dysbalance and to form fault motoric stereotype. Periodic compensatory exercise which is made by relaxation, stretching and weight training with breathing exercise and relaxation exercise can help...

  13. Analyzing One-Sided vs. Two-Sided Subduction Arising from Mantle Convection Simulations

    Science.gov (United States)

    Kaplan, M. S.; Becker, T. W.

    2013-12-01

    Purely thermal plate tectonic generation models struggle to consistently reproduce one-sided subduction as is observed on Earth (Tackley 2000; Van Heck and Tackley 2008; Foley and Becker 2009), and instead produce two-sided subduction where the subducting slab contains a significant flux of material from both plates. The models of Crameri et al. (2012) demonstrate that the implementation of a free upper surface boundary condition and the inclusion of a weak hydrated crust can facilitate one-sided subduction. We employ a similar model configuration to Crameri et al. (2012) to further investigate the dynamics and energetics which are associated with one-sided vs. two-sided subduction. We use a 2D finite difference code based off of the algorithms of I2ELVIS (Gerya and Yuen 2007) where material parameters are tracked on Lagrangian markers and the Stokes and Energy equations are solved on a Cartesian grid. A free surface is implemented by a low viscosity and density 'sticky air layer' (Schmeling et al., 2008; Crameri et al., 2012) with the stabilization routine of Duretz et al. (2011) to prevent the 'drunken seaman' instability (Kaus et al., 2010). The effects of a weak crust, shear heating, a free surface or free slip upper mechanical boundary condition, plasticity as a function of depth or pressure, and the sticky air layer thermal conductivity on one-sided vs. two-sided subduction are investigated. When we observe one-sided subduction it is transient and can smoothly evolve back to a two-sided configuration. In our models, 'sidedness' is a spectrum, rather than either discretely one or two sided, and the models move between the two regimes throughout the model runs. We observe that the thermal conductivity of the sticky air layer can influence the dynamics of the convective domain. Elevated values of thermal conductivity compared to those of rock must be implemented in the sticky air layer in order to maintain a constant temperature at the surface of the convective

  14. Group Learning.

    Science.gov (United States)

    Black, Susan

    1992-01-01

    Research suggests that cooperative learning works best when students are first taught group-processing skills, such as leadership, decision making, communication, trust building, and conflict management. Inadequate teacher training and boring assignments can torpedo cooperative learning efforts. Administrators should reassure teachers with…

  15. Tectaria group

    NARCIS (Netherlands)

    Holttum, R.E.

    1991-01-01

    Polypodiaceae subfam. Dryopteridoideae section A, auct.: C. Chr. in Verdoorn, Man. Pteridol. (1938) 543, p.p. Aspidiaceae tribe Aspidieae auct.: Ching, Sunyatsenia 5 (1940) 250, excl. Lomariopsis and related genera. — Aspidiaceae, group of Ctenitis Copel., Gen. Fil. (1947) 153. Aspidiaceae auct.: Pi

  16. Effects of number of side dumps and side dump angles on outlet parameters in a side-dump combustor

    Science.gov (United States)

    Mojtahedpoor, M.; Doustdar, M. M.; Soltani, H.; Chegini, M.

    2012-11-01

    A numerical study on the effect of side-dump number on fuel droplets sizing and effective mass fraction have been investigated in present paper. The mass of fuel vapor inside the flammability limit is named as the effective mass fraction. In the first step we have considered a side-dump combustor with two dumps and dump angle of 0o (plumb to cylinder) and by increasing the entrance airflow velocity from 20 to 30, 40 and 50 (m/s) respectively, the mean diameter of fuel droplets sizing and effective mass fraction have been studied. After this step, we have changed the number of dumps from two to four and we have repeated last examination again. To fulfill the calculations a modified version of KIVA-3V code which is a transient, three-dimensional, multiphase, multicomponent code for the analysis of chemically reacting flows with sprays, is used.

  17. PREVENTION OF CUTANEOUS SIDE EFFECTS OF TOPICAL TRETINOIN: USE OF ORAL VITAMINE E

    Directory of Open Access Journals (Sweden)

    G FAGHIHI

    2001-03-01

    Full Text Available Introduction: Acne vulgaris is an inflammatory disease of pilosebaceous folicles. Tretinoin is used as one of the topical treatments for acne vulgaris. It has different cutaneous side effects such as erythema, scaling, irritation and photosensitivity. The aim of this study was to evaluate the efficacy of oral Vitamine E in preventing the cutaneous side effects of topical tretinoin in acne patients.
    Methods: A clinical trial was performed in AI-Zahra Hospital in Isfahan for six months in 2000. 80 patients with mild to moderate facial acne were randomized into 2 groups. Group 1 (controls received topical solution of tretinoin 0.05 percent nightly and group 2 (cases received daily oral 100mg of Vit. E in addition. All patients were followed at 1, 4 and 6 weeks after initiation of treatment. Children under 12 years old, pregnant or lactating women were excluded.
    Results: At the end of one week, no cutaneous side effects were observed in 25 percent (10 of group 1 and 15 percent (6 of group 2 (P > 0.05. At the end of 4 weeks, 25 percent (10 of group 1 and 60 percent (24 of group 2 were without any cutaneous complications, while at the end of 6 weeks, 35 percent (14 of group 1 in comparison to 75 percent (30 of group 2 were free of any cutaneous side effects (P < 0.05. The most common side effect in both groups was exfoliation.
    Discussion: Daily oral 100 mg of Vit. E has been effective in preventing cutaneous complications of topical tretinoin in acne management, but there is a delay of one week in its onset of action. Meanwhile, Vitamine E is a safe modality with no undesirable effects in acne patients.

  18. COMMUNICATIONS GROUP

    CERN Multimedia

    L. Taylor

    2011-01-01

    The CMS Communications Group, established at the start of 2010, has been busy in all three areas of its responsibility: (1) Communications Infrastructure, (2) Information Systems, and (3) Outreach and Education. Communications Infrastructure There are now 55 CMS Centres worldwide that are well used by physicists working on remote CMS shifts, Computing operations, data quality monitoring, data analysis and outreach. The CMS Centre@CERN in Meyrin, is the centre of the CMS offline and computing operations, hosting dedicated analysis efforts such as during the CMS Heavy Ion lead-lead running. With a majority of CMS sub-detectors now operating in a “shifterless” mode, many monitoring operations are now routinely performed from there, rather than in the main Control Room at P5. The CMS Communications Group, CERN IT and the EVO team are providing excellent videoconferencing support for the rapidly-increasing number of CMS meetings. In parallel, CERN IT and ...

  19. Group therapy

    International Nuclear Information System (INIS)

    Full text: In his review 'Genesis of Unified Gauge Theories' at the symposium in Honour of Abdus Salam (June, page 23), Tom Kibble of Imperial College, London, looked back to the physics events around Salam from 1959-67. He described how, in the early 1960s, people were pushing to enlarge the symmetry of strong interactions beyond the SU(2) of isospin and incorporate the additional strangeness quantum number. Kibble wrote - 'Salam had students working on every conceivable symmetry group. One of these was Yuval Ne'eman, who had the good fortune and/or prescience to work on SU(3). From that work, and of course from the independent work of Murray Gell- Mann, stemmed the Eightfold Way, with its triumphant vindication in the discovery of the omega-minus in 1964.' Yuval Ne'eman writes - 'I was the Defence Attaché at the Israeli Embassy in London and was admitted by Salam as a part-time graduate student when I arrived in 1958. I started research after resigning from the Embassy in May 1960. Salam suggested a problem: provide vector mesons with mass - the problem which was eventually solved by Higgs, Guralnik, Kibble,.... (as described by Kibble in his article). I explained to Salam that I had become interested in symmetry. Nobody at Imperial College at the time, other than Salam himself, was doing anything in groups, and attention further afield was focused on the rotation - SO(N) - groups. Reacting to my own half-baked schemes, Salam told me to forget about the rotation groups he taught us, and study group theory in depth, directing me to Eugene Dynkin's classification of Lie subalgebras, about which he had heard from Morton Hamermesh. I found Dynkin incomprehensible without first learning about Lie algebras from Henri Cartan's thesis, which luckily had been reproduced by Dynkin in his 1946 thesis, using his diagram method. From a copy of a translation of Dynkin's thesis which I found in the British Museum Library, I

  20. Measurement of Bd mixing using opposite-side flavor tagging

    CERN Document Server

    Abazov, V M; Abolins, M; Acharya, B S; Adams, M; Adams, T; Agelou, M; Aguiló, E; Ahn, S H; Ahsan, M; Alexeev, G D; Alkhazov, G; Alton, A; Alverson, G; Alves, G A; Anastasoaie, M; Andeen, T; Anderson, S; Andrieu, B; Anzelc, M S; Arnoud, Y; Arov, M; Askew, A; Åsman, B; Assis-Jesus, A C S; Atramentov, O; Autermann, C; Avila, C; Ay, C; Badaud, F; Baden, A; Bagby, L; Baldin, B; Bandurin, D V; Banerjee, P; Banerjee, S; Barberis, E; Bargassa, P; Baringer, P; Barnes, C; Barreto, J; Bartlett, J F; Bassler, U; Bauer, D; Beale, S; Bean, A; Begalli, M; Begel, M; Belanger-Champagne, C; Bellantoni, L; Bellavance, A; Benítez, J A; Beri, S B; Bernardi, G; Bernhard, R; Berntzon, L; Bertram, I; Besançon, M; Beuselinck, R; Bezzubov, V A; Bhat, P C; Bhatnagar, V; Binder, M; Biscarat, C; Black, K M; Blackler, I; Blazey, G; Blekman, F; Blessing, S; Bloch, D; Bloom, K; Blumenschein, U; Böhnlein, A; Boeriu, O; Bolton, T A; Borissov, G; Bos, K; Bose, T; Brandt, A; Brock, R; Brooijmans, G; Bross, A; Brown, D; Buchanan, N J; Buchholz, D; Bühler, M; Büscher, V; Burdin, S; Burke, S; Burnett, T H; Busato, E; Buszello, C P; Butler, J M; Calfayan, P; Calvet, S; Cammin, J; Caron, S; Carvalho, W; Casey, B C K; Cason, N M; Castilla-Valdez, H; Chakrabarti, S; Chakraborty, D; Chan, K M; Chandra, A; Charles, F; Cheu, E; Chevallier, F; Cho, D K; Choi, S; Choudhary, B; Christofek, L; Claes, D; Clement, B; Clément, C; Coadou, Y; Cooke, M; Cooper, W E; Coppage, D; Corcoran, M; Cousinou, M C; Cox, B; Crepe-Renaudin, S; Cutts, D; Cwiok, M; Da Motta, H; Das, A; Das, M; Davies, B; Davies, G; Davis, G A; De, K; de Jong, P; De Jong, S J; De La Cruz-Burelo, E; De Oliveira Martins, C; Degenhardt, J D; Déliot, F; Demarteau, M; Demina, R; Demine, P; Denisov, D; Denisov, S P; Desai, S; Diehl, H T; Diesburg, M; Doidge, M; Dominguez, A; Dong, H; Dudko, L V; Duflot, L; Dugad, S R; Duggan, D; Duperrin, A; Dyer, J; Dyshkant, A; Eads, M; Edmunds, D; Edwards, T; Ellison, J; Elmsheuser, J; Elvira, V D; Eno, S; Ermolov, P; Evans, H; Evdokimov, A; Evdokimov, V N; Fatakia, S N; Feligioni, L; Ferapontov, A V; Ferbel, T; Fiedler, F; Filthaut, F; Fisher, W; Fisk, H E; Fleck, I; Ford, M; Fortner, M; Fox, H; Fu, S; Fuess, S; Gadfort, T; Galea, C F; Gallas, E; Galyaev, E; García, C; García-Bellido, A; Gardner, J; Gavrilov, V; Gay, A; Gay, P; Gelé, D; Gelhaus, R; Gerber, C E; Gershtein, Yu; Gillberg, D; Ginther, G; Gollub, N; Gómez, B; Goussiou, A; Grannis, P D; Greenlee, H; Greenwood, Z D; Gregores, E M; Grenier, G; Gris, P; Grivaz, J F; Grünendahl, S; Grünewald, M W; Guo, F; Guo, J; Gutíerrez, G; Gutíerrez, P; Haas, A; Hadley, N J; Haefner, P; Hagopian, S; Haley, J; Hall, I; Hall, R E; Han, L; Hanagaki, K; Hansson, P; Harder, K; Harel, A; Harrington, R; Hauptman, J M; Hauser, R; Hays, J; Hebbeker, T; Hedin, D; Hegeman, J G; Heinmiller, J M; Heinson, A P; Heintz, U; Hensel, C; Herner, K; Hesketh, G; Hildreth, M D; Hirosky, R; Hobbs, J D; Hoeneisen, B; Hoeth, H; Hohlfeld, M; Hong, S J; Hooper, R; Houben, P; Hu, Y; Hubacek, Z; Hynek, V; Iashvili, I; Illingworth, R; Ito, A S; Jabeen, S; Jaffré, M; Jain, S; Jakobs, K; Jarvis, C; Jenkins, A; Jesik, R; Johns, K; Johnson, C; Johnson, M; Jonckheere, A; Jonsson, P; Juste, A; Käfer, D; Kahn, S; Kajfasz, E; Kalinin, A M; Kalk, J M; Kalk, J R; Kappler, S; Karmanov, D; Kasper, J; Kasper, P; Katsanos, I; Kau, D; Kaur, R; Kehoe, R; Kermiche, S; Khalatyan, N; Khanov, A; Kharchilava, A I; Kharzheev, Yu M; Khatidze, D; Kim, H; Kim, T J; Kirby, M H; Klima, B; Kohli, J M; Konrath, J P; Kopal, M; Korablev, V M; Kotcher, J; Kothari, B; Koubarovsky, A; Kozelov, A V; Krop, D; Kryemadhi, A; Kühl, T; Kumar, A; Kunori, S; Kupco, A; Kurca, T; Kvita, J; Lammers, S; Landsberg, G L; Lazoflores, J; Le Bihan, A C; Lebrun, P; Lee, W M; Leflat, A; Lehner, F; Lesne, V; Lévêque, J; Lewis, P; Li, J; Li, Q Z; Lima, J G R; Lincoln, D; Linnemann, J; Lipaev, V V; Lipton, R; Liu, Z; Lobo, L; Lobodenko, A; Lokajícek, M; Lounis, A; Love, P; Lubatti, H J; Lynker, M; Lyon, A L; Maciel, A K A; Madaras, R J; Mättig, P; Magass, C; Magerkurth, A; Magnan, A M; Makovec, N; Mal, P K; Malbouisson, H B; Malik, S; Malyshev, V L; Mao, H S; Maravin, Y; Martens, M; McCarthy, R; Meder, D; Melnitchouk, A; Mendes, A; Mendoza, L; Merkin, M; Merritt, K W; Meyer, A; Meyer, J; Michaut, M; Miettinen, H; Millet, T; Mitrevski, J; Molina, J; Mondal, N K; Monk, J; Moore, R W; Moulik, T; Muanza, G S; Mulders, M; Mulhearn, M; Mundal, O; Mundim, L; Mutaf, Y D; Nagy, E; Naimuddin, M; Narain, M; Naumann, N A; Neal, H A; Negret, J P; Neustroev, P; Nöding, C; Nomerotski, A; Novaes, S F; Nunnemann, T; O'Dell, V; O'Neil, D C; Obrant, G; Oguri, V; Oliveira, N; Onoprienko, D; Oshima, N; Otec, R; Oteroy-Garzon, G J; Owen, M; Padley, P; Parashar, N; Park, S J; Park, S K; Parsons, J; Partridge, R; Parua, N; Patwa, A; Pawloski, G; Perea, P M; Pérez, E; Peters, K; Petroff, P; Petteni, M; Piegaia, R; Piper, J; Pleier, M A; Podesta-Lerma, P L M; Podstavkov, V M; Pogorelov, Y; Pol, M E; Pompos, A; Pope, B G; Popov, A V; Potter, C; Prado da Silva, W L; Prosper, H B; Protopopescu, S D; Qian, J; Quadt, A; Quinn, B; Rangel, M S; Rani, K J; Ranjan, K; Ratoff, P N; Renkel, P; Reucroft, S; Rijssenbeek, M; Ripp-Baudot, I; Rizatdinova, F K; Robinson, S; Rodrigues, R F; Royon, C; Rubinov, P; Ruchti, R; Rud, V I; Sajot, G; Sánchez-Hernández, A; Sanders, M P; Santoro, A F S; Savage, G; Sawyer, L; Scanlon, T; Schaile, A D; Schamberger, R D; Scheglov, Y; Schellman, H; Schieferdecker, P; Schmitt, C; Schwanenberger, C; Schwartzman, A; Schwienhorst, R; Sekaric, J; Sen-Gupta, S; Severini, H; Shabalina, E; Shamim, M; Shary, V; Shchukin, A A; Shephard, W D; Shivpuri, R K; Shpakov, D; Siccardi, V; Sidwell, R A; Simák, V; Sirotenko, V I; Skubic, P L; Slattery, P F; Smith, R P; Snow, G R; Snow, J; Snyder, S; Söldner-Rembold, S; Song, X; Sonnenschein, L; Sopczak, A; Sosebee, M; Soustruznik, K; Souza, M; Spurlock, B; Stark, J; Steele, J; Stolin, V; Stone, A; Stoyanova, D A; Strandberg, J; Strandberg, S; Strang, M A; Strauss, M; Ströhmer, R; Strom, D; Strovink, M; Stutte, L; Sumowidagdo, S; Svoisky, P; Sznajder, A; Talby, M; Tamburello, P; Taylor, W; Telford, P; Temple, J; Tiller, B; Titov, M; Tokmenin, V V; Tomoto, M; Toole, T; Torchiani, I; Towers, S; Trefzger, T; Trincaz-Duvoid, S; Tsybychev, D; Tuchming, B; Tully, C; Turcot, A S; Tuts, P M; Unalan, R; Uvarov, L; Uvarov, S; Uzunyan, S; Vachon, B; vanden Berg, P J; Van Kooten, R; Van Leeuwen, W M; Varelas, N; Varnes, E W; Vartapetian, A H; Vasilyev, I A; Vaupel, M; Verdier, P; Vertogradov, L S; Verzocchi, M; Villeneuve-Séguier, F; Vint, P; Vlimant, J R; Von Törne, E; Voutilainen, M; Vreeswijk, M; Wahl, H D; Wang, L; Wang, M H L; Warchol, J; Watts, G; Wayne, M; Weber, G; Weber, M; Weerts, H; Wermes, N; Wetstein, M; White, A; Wicke, D; Wilson, G W; Wimpenny, S J; Wobisch, M; Womersley, J; Wood, D R; Wyatt, T R; Xie, Y; Xuan, N; Yacoob, S; Yamada, R; Yan, M; Yasuda, T; Yatsunenko, Y A; Yip, K; Yoo, H D; Youn, S W; Yu, C; Yu, J; Yurkewicz, A; Zatserklyaniy, A; Zeitnitz, C; Zhang, D; Zhao, T; Zhou, B; Zhu, J; Zielinski, M; Zieminska, D; Zieminski, A; Zutshi, V; Zverev, E G

    2006-01-01

    We report on a measurement of the $B^0_d$ mixing frequency and the calibration of an opposite-side flavor tagger in the D{\\O}experiment. Various properties associated with the $b$ quark on the opposite side of the reconstructed $B$ meson were combined using a likelihood-ratio method into a single variable with enhanced tagging power. Its performance was tested with data, using a large sample of reconstructed semileptonic $B \\to \\mu \\dzero X$ and $B \\to \\mu \\dst X$ decays, corresponding to an integrated luminosity of approximately 1 fb$^{-1}$. The events were divided into groups depending on the value of the combined tagging variable, and an independent analysis was performed in each group. Combining the results of these analyses, the overall effective tagging power was found to be eD^2 = (2.48 \\pm 0.21 (stat.) ^{+0.08}_{-0.06} (syst.))%. The measured $B^0_d$ mixing frequency dmd = 0.506 \\pm 0.020 {\\rm (stat) \\pm 0.016 (syst) ps}^{-1} is in good agreement with the world average value.

  1. Local Group

    Science.gov (United States)

    Mateo, M.; Murdin, P.

    2000-11-01

    Not long after EDWIN HUBBLE established that galaxies are `island universes' similar to our home galaxy, the MILKY WAY, he realized that a few of these external galaxies are considerably closer to us than any others. In 1936 he first coined the term `Local Group' in his famous book The Realm of the Nebulae to identify our nearest galactic neighbors. More than 60 yr later, the galaxies of the Loca...

  2. The effects of the application of low-dye taping on paretic side plantar pressure among patients with plantar fasciitis.

    Science.gov (United States)

    Park, Chan; Lee, Sangyong; Kim, Shingyun; Hwangbo, Gak

    2015-11-01

    [Purpose] This study aimed to examine the effects of low-dye taping on paretic side plantar pressure in patients with plantar fasciitis. [Subjects] The 30 patients in this study were randomly allocated to a low-dye taping group (n = 15) or a conservative treatment group (n =15). [Methods] Both groups received treatment thrice a week for six weeks. BioRescue was used to measure the weight distribution of the patients' paretic side. [Results] Within-group comparison showed that the posterior weight distribution significantly increased among patients in both groups. However, comparison between the two groups showed that the low-dye taping group's posterior weight distribution was significantly higher than that of the conservative treatment group. [Conclusion] These findings show that the application of low-dye taping is an effective intervention for paretic-side plantar pressure among patients with plantar fasciitis. PMID:26696737

  3. Server-side Statistics Scripting in PHP

    Directory of Open Access Journals (Sweden)

    Jan de Leeuw

    1997-06-01

    Full Text Available On the UCLA Statistics WWW server there are a large number of demos and calculators that can be used in statistics teaching and research. Some of these demos require substantial amounts of computation, others mainly use graphics. These calculators and demos are implemented in various different ways, reflecting developments in WWW based computing. As usual, one of the main choices is between doing the work on the client-side (i.e. in the browser or on the server-side (i.e. on our WWW server. Obviously, client-side computation puts fewer demands on the server. On the other hand, it requires that the client downloads Java applets, or installs plugins and/or helpers. If JavaScript is used, client-side computations will generally be slow. We also have to assume that the client is installed properly, and has the required capabilities. Requiring too much on the client-side has caused browsing machines such as Netscape Communicator to grow beyond all reasonable bounds, both in size and RAM requirements. Moreover requiring Java and JavaScript rules out such excellent browsers as Lynx or Emacs W3. For server-side computing, we can configure the server and its resources ourselves, and we need not worry about browser capabilities and configuration. Nothing needs to be downloaded, except the usual HTML pages and graphics. In the same way as on the client side, there is a scripting solution, where code is interpreted, or a ob ject-code solution using compiled code. For the server-side scripting, we use embedded languages, such as PHP/FI. The scripts in the HTML pages are interpreted by a CGI program, and the output of the CGI program is send to the clients. Of course the CGI program is compiled, but the statistics procedures will usually be interpreted, because PHP/FI does not have the appropriate functions in its scripting language. This will tend to be slow, because embedded languages do not deal efficiently with loops and similar constructs. Thus a first

  4. CORTICAL CLEANUP WITHOUT SIDE PORT IN SMALL INCISION CATARACT SURGERY

    Directory of Open Access Journals (Sweden)

    Udaya Kumar

    2015-11-01

    Full Text Available The aim of study was to achieve complete cortical cleanup and avoid problems related with sideport during Small Incision Cataract Surgery (SICS so as to have a good visual out come with minimal recovery period, and a better quality of life. After nucleus delivery, cortical cleanup is an important step in any cataract surgical procedure. Cortex especially subincisional area (11 to 1 o’clock is difficult to manage intraoperatively. Bimanual irrigation aspiration through two side ports, aspiration by J cannula, iris massage manoeuver, ice cream scoop manoeuver are various techniques of cortical matter aspiration. We acquired the technique of aspiration of subincisional cortex without using side port in all cases by paying attention on type of cataract, status of pupil, use of Adrenalin mixed BSS intraoperatively, Tunnel construction, Capsulorhexis size and capsular rim size at 12 o’clock. MATERIAL AND METHODS In this retrospective study of 1 year from 2013 to 2014, 60 patients (60 eyes aged 40 years or older attending the General Ophthalmic Department were included in the study group with another group of 60 patients (60 eyes as controls. The study was on age related cataracts which are basically. 1 Cortical cataract 2 Nuclear cataract 3 Subcapsular cataract. Proper assessment of cortical cataract based on its maturity such as a Immature b Mature c Hyper mature and d Morgagnian cataract, nucleus for its opalescence and color, size of posterior subcapsular opacity and pupillary status (Dilating well or not with mydriatics were taken into consideration. Eyes with pseudoexfoliation having poor pupillary dilation were also included. Eyes with congenital anomalies, congenital cataract, gross corneal and retinal pathologies, and glaucoma were excluded. RESULTS Among 60 study eyes in the study group 35 presented with cortical, 20 with nuclear cataract and 5 with posterior subcapsular cataracts. In 58(96.6% cases, sideport was not required; 3(5% eyes

  5. The Dark Side of the Moon

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A combo photo released by the China National Space Administration(CNSA)on December 11 shows a crater on the dark side of the moon.This image was reportedly taken by Chang’e-1, the country’s first lunar probe,on December 4. On December 12,a grand ceremony was held in Beijing to celebrate the success of the first stage of China’s lunar probe program.President Hu Jintao announced on the occasion that the

  6. Photon side-bands in mesoscopics

    DEFF Research Database (Denmark)

    Jauho, Antti-Pekka

    1998-01-01

    This paper reviews several applications of photonic side bands, used by Buttiker and Landauer (Phys. Rev. Lett. 49, 1739 (1982)) in their theory of traversal time in tunneling, in transport and optics of mesoscopic systems. Topics include generalizations of the transmission theory of transport to...... time-dependent situations, optics and transport of mesoscopic systems in THz electromagnetic fields, and phase-measurements of photon-assisted tunneling through a quantum dot. (C) 1998 Academic Press Limited....

  7. The light and dark side of TARP

    OpenAIRE

    Uhde, Andre; Farruggio, Christian; Tobias C. Michalak

    2013-01-01

    This paper empirically investigates the impact of the first announcement of TARP, the announcement of revised TARP, respective capital infusions under TARP-CPP and capital repayments on changes in shareholder value and the risk exposure of supported U.S. banks. Our analysis reveals a light and a dark side of TARP. While announcements as well as capital repayments may provoke positive wealth effects and a decrease in bank risk, equity capital injections to banks are observed to be a severe imp...

  8. The human side of animal behavior

    OpenAIRE

    Lattal, Kennon A.

    2001-01-01

    An important element of behavioral research with nonhuman animals is that insights are drawn from it about human behavior, what is called here the human side of animal behavior. This article examines the origins of comparing human behavior to that of other animals, the ways in which such comparisons are described, and considerations that arise in evaluating the validity of those comparisons. The rationale for such an approach originated in the reductionism of experimental physiology and the u...

  9. Side-information Scalable Source Coding

    CERN Document Server

    Tian, Chao

    2007-01-01

    The problem of side-information scalable (SI-scalable) source coding is considered in this work, where the encoder constructs a progressive description, such that the receiver with high quality side information will be able to truncate the bitstream and reconstruct in the rate distortion sense, while the receiver with low quality side information will have to receive further data in order to decode. We provide inner and outer bounds for general discrete memoryless sources. The achievable region is shown to be tight for the case that either of the decoders requires a lossless reconstruction, as well as the case with degraded deterministic distortion measures. Furthermore we show that the gap between the achievable region and the outer bounds can be bounded by a constant when square error distortion measure is used. The notion of perfectly scalable coding is introduced as both the stages operate on the Wyner-Ziv bound, and necessary and sufficient conditions are given for sources satisfying a mild support condi...

  10. Safety Assessment for a Side-by-side Offloading Mooring System

    Institute of Scientific and Technical Information of China (English)

    Liping Sun; Qiang He; Shangmao Ai

    2011-01-01

    In order to improve the safety properties of an offloading system with side-by-side (SBS) mooring in which the FPSO is moored by a yoke system in the field of BZ25-1,it is necessary to analyze those properties.According to the experience of similar projects,tow strategies of different offloading arrangements were discussed by using the 3-D radiation/diffraction theory and quasi-static time domain method to assess their respective safety properties.Through the safety assessment analysis of different arrangement comparisons,various ways to improve the safety properties of offloading systems with side-by-side mooring were verified by analyzing the tension in the mooring lines and the fender deflection.Through comparison it can be concluded that by enlarging the key factors properly,including the size of the fenders and the hawsers as well as the number of hawsers,a better satiety performance can be achieved.

  11. Side-to-Side Cold Welding for Controllable Nanogap Formation from "Dumbbell" Ultrathin Gold Nanorods.

    Science.gov (United States)

    Dai, Gaole; Wang, Binjun; Xu, Shang; Lu, Yang; Shen, Yajing

    2016-06-01

    Cold welding has been regarded as a promising bottom-up nanofabrication technique because of its ability to join metallic nanostructures at room temperature with low applied stress and without introducing damage. Usually, the cold welding process can be done instantaneously for ultrathin nanowires (diameter welded in the "side-to-side" mode in a highly controllable manner and can form an extremely small nanogap via a relatively slow welding process (up to tens of minutes, allowing various functional applications). By combining in situ high-resolution transmission electron microscopic analysis and molecular dynamic simulations, we further reveal the underlying mechanism for this "side-to-side" welding process as being dominated by atom kinetics instead of thermodynamics, which provides critical insights into three-dimensional nanosystem integration as well as the building of functional nanodevices. PMID:27173140

  12. Electronic vs. Open Outcry: Side-by-Side Trading of KCBT Wheat Futures

    OpenAIRE

    Shah, Samarth; Brorsen, B. Wade

    2011-01-01

    This study compares liquidity costs of electronic and open-outcry wheat futures contracts traded side-by-side on the Kansas City Board of Trade. Liquidity costs are considerably lower in the electronic market. Liquidity costs in the electronic market are still considerably lower after eliminating the bias created by splitting orders in the electronic market. Price volatility and transaction size are positively related to liquidity costs, while a negative relation is found between daily volume...

  13. 2D flow around stationary side-by-side square columns at low Reynolds number

    OpenAIRE

    Mengzhao, Guan; Shengwei, Ma; Siracusa, Francesca; Chang-Wei, Kang; Teck-Bin Arthur, Lim; Weymouth, Gabriel; Tutty, Owen; Mingyi, Tan; Hudson, Dominic; Kumar Jaiman, Rajeev; Chih-Hua, Wu

    2015-01-01

    Flow over two side-by-side square columns is studied numerically and experimentally at low Reynolds number (Re=100-200) to investigate the effects of the gap distance on the behaviour of the flow. Different gap distances between two square columns are simulated to analyse the interactions of laminar wakes with a gap flow. Four different flow regimes are observed based on different gap distance. Experimental test are performed to validate the simulations. A new water tank has been built specif...

  14. Poisson structures on the Poincare group

    OpenAIRE

    Zakrzewski, S.

    1996-01-01

    An introduction to inhomogeneous Poisson groups is given. Poisson inhomogeneous $O(p,q)$ are shown to be coboundary, the generalized classical Yang-Baxter equation having only one-dimensional right hand side. Normal forms of the classical $r$-matrices for the Poincar\\'{e} group (inhomogeneous $O(1,3)$) are calculated.

  15. COMMUNICATIONS GROUP

    CERN Multimedia

    L. Taylor

    2010-01-01

    The CMS Communications Group, established at the start of 2010, has been strengthening the activities in all three areas of its responsibility: (1) Communications Infrastructure, (2) Information Systems, and (3) Outreach and Education. Communications Infrastructure The Communications Group has invested a lot of effort to support the operations needs of CMS. Hence, the CMS Centres where physicists work on remote CMS shifts, Data Quality Monitoring, and Data Analysis are running very smoothly. There are now 55 CMS Centres worldwide, up from just 16 at the start of CMS data-taking. The latest to join are Imperial College London, the University of Iowa, and the Università di Napoli. The CMS Centre@CERN in Meyrin, which is now full repaired after the major flooding at the beginning of the year, has been at the centre of CMS offline and computing operations, most recently hosting a large fraction of the CMS Heavy Ion community during the lead-lead run. A number of sub-detector shifts can now take pla...

  16. COMMUNICATIONS GROUP

    CERN Multimedia

    L. Taylor

    2011-01-01

    The CMS Communications Group has been busy in all three areas of its responsibility: (1) Communications Infrastructure, (2) Information Systems, and (3) Outreach and Education. Communications Infrastructure The 55 CMS Centres worldwide are well used by physicists working on remote CMS shifts, Computing operations, data quality monitoring, data analysis and outreach. The CMS Centre@CERN in Meyrin, is the centre of the CMS Offline and Computing operations, and a number of subdetector shifts can now take place there, rather than in the main Control Room at P5. A new CMS meeting room has been equipped for videoconferencing in building 42, next to building 40. Our building 28 meeting room and the facilities at P5 will be refurbished soon and plans are underway to steadily upgrade the ageing equipment in all 15 CMS meeting rooms at CERN. The CMS evaluation of the Vidyo tool indicates that it is not yet ready to be considered as a potential replacement for EVO. The Communications Group provides the CMS-TV (web) cha...

  17. Stabilization of Gob-Side Entry with an Artificial Side for Sustaining Mining Work

    Directory of Open Access Journals (Sweden)

    Hong-sheng Wang

    2016-07-01

    Full Text Available A concrete artificial side (AS is introduced to stabilize a gob-side entry (GSE. To evaluate the stability of the AS, a uniaxial compression failure experiment was conducted with large and small-scale specimens. The distribution characteristics of the shear stress were obtained from a numerical simulation. Based on the failure characteristics and the variation of the shear stress, a failure criterion was determined and implemented in the strengthening method for the artificial side. In an experimental test, the distribution pattern of the maximum shear stress showed an X shape, which contributed to the failure shape of the specimen. The shear stress distribution and failure shape are induced by a combination of two sets of shear stresses, which implies that failure of the AS follows the twin shear strength theory. The use of anchor bolts, bolts, and anchor bars enhances the shear strength of the artificial side. When this side is stable, the components can constrain the lateral deformation as well as improve the internal friction angle and cohesion. When the AS is damaged, the components prevent the sliding of broken blocks along the shear failure plane and improve the residual strength of the artificial side. When reinforced with an anchor bar, the AS is still stable even after mining operations for three years.

  18. Angle Specific Analysis of Side-to-Side Asymmetry in the Shoulder Rotators

    Directory of Open Access Journals (Sweden)

    Cassio V. Ruas

    2015-08-01

    Full Text Available Although side-to-side asymmetry of the shoulder rotators calculated by independent peak torque (IPT has been used for interpretation of injury risks in athletes, it may not measure strength through the entire range of motion (ROM tested. The aim of this study was to compare side-to-side asymmetry of the shoulder rotators between independent peak torque (IPT and ten-degree angle specific torque (AST. Twenty healthy adult males (24.65 ± 2.4 years performed concentric and eccentric internal rotation (IR and external rotation (ER of the preferred and non-preferred arms on an isokinetic dynamometer at 60°/s through 150° of total ROM. The total ROM was divided into 14 ten-degree angles of the physiological ROM from −90° of ER to 60° of IR. Concentric and eccentric IR IPT (10.5% ± 8.7% and 12.1% ± 7.2% and ER IPT (13.6% ± 9.8% and 8.7% ± 5.6% were significantly less than AST at several angles (p < 0.05. IPT might lead to erroneous interpretations of side-to-side asymmetry in the shoulder rotators and does not represent the entire ROM tested. This information could be used to prescribe strength exercises to enhance overhead performance and reduce risk of shoulder injuries.

  19. Temperature dependence of amino acid side chain IR absorptions in the amide I' region.

    Science.gov (United States)

    Anderson, Benjamin A; Literati, Alex; Ball, Borden; Kubelka, Jan

    2014-05-01

    Amide I' IR spectra are widely used for studies of structural changes in peptides and proteins as a function of temperature. Temperature dependent absorptions of amino acid side-chains that overlap the amide I' may significantly complicate the structural analyses. While the side-chain IR spectra have been investigated previously, thus far their dependence on temperature has not been reported. Here we present the study of the changes in the IR spectra with temperature for side-chain groups of aspartate, glutamate, asparagine, glutamine, arginine, and tyrosine in the amide I' region (in D2O). Band fitting analysis was employed to extract the temperature dependence of the individual spectral parameters, such as peak frequency, integrated intensity, band width, and shape. As expected, the side-chain IR bands exhibit significant changes with temperature. The majority of the spectral parameters, particularly the frequency and intensity, show linear dependence on temperature, but the direction and magnitude vary depending on the particular side-chain group. The exception is arginine, which exhibits a distinctly nonlinear frequency shift with temperature for its asymmetric CN3H5(+) bending signal, although a linear fit can account for this change to within ~1/3 cm(-1). The applicability of the determined spectral parameters for estimations of temperature-dependent side-chain absorptions in peptides and proteins are discussed.

  20. The acute side effects of bright light therapy: a placebo-controlled investigation.

    Directory of Open Access Journals (Sweden)

    Yevgeny Botanov

    Full Text Available Despite the emergence of numerous clinical and non-clinical applications of bright light therapy (LT in recent decades, the prevalence and severity of LT side effects have not yet been fully explicated. A few adverse LT effects-headache, eye strain, irritability, and nausea-have been consistently reported among depressed individuals and other psychiatric cohorts, but there exists little published evidence regarding LT side effects in non-clinical populations, who often undergo LT treatment of considerably briefer duration. Accordingly, in the present study we examined, in a randomized sample of healthy young adults, the acute side effects of exposure to a single 30-minute session of bright white light (10,000 lux versus dim red light (< 500 lux. Across a broad range of potential side effects, repeated-measures analyses of variance revealed no significant group-by-time (Pre, Post interactions. In other words, bright light exposure was not associated with a significantly higher incidence of any reported side effect than was the placebo control condition. Nevertheless, small but statistically significant increases in both eye strain and blurred vision were observed among both the LT and control groups. Overall, these results suggest that the relatively common occurrence of adverse side effects observed in the extant LT literature may not fully extend to non-clinical populations, especially for healthy young adults undergoing LT for a brief duration.

  1. Cardiovascular group

    Science.gov (United States)

    Blomqvist, Gunnar

    1989-01-01

    As a starting point, the group defined a primary goal of maintaining in flight a level of systemic oxygen transport capacity comparable to each individual's preflight upright baseline. The goal of maintaining capacity at preflight levels would seem to be a reasonable objective for several different reasons, including the maintenance of good health in general and the preservation of sufficient cardiovascular reserve capacity to meet operational demands. It is also important not to introduce confounding variables in whatever other physiological studies are being performed. A change in the level of fitness is likely to be a significant confounding variable in the study of many organ systems. The principal component of the in-flight cardiovascular exercise program should be large-muscle activity such as treadmill exercise. It is desirable that at least one session per week be monitored to assure maintenance of proper functional levels and to provide guidance for any adjustments of the exercise prescription. Appropriate measurements include evaluation of the heart-rate/workload or the heart-rate/oxygen-uptake relationship. Respiratory gas analysis is helpful by providing better opportunities to document relative workload levels from analysis of the interrelationships among VO2, VCO2, and ventilation. The committee felt that there is no clear evidence that any particular in-flight exercise regimen is protective against orthostatic hypotension during the early readaptation phase. Some group members suggested that maintenance of the lower body muscle mass and muscle tone may be helpful. There is also evidence that late in-flight interventions to reexpand blood volume to preflight levels are helpful in preventing or minimizing postflight orthostatic hypotension.

  2. Side chain engineering of poly-thiophene and its impact on crystalline silicon based hybrid solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Zellmeier, M.; Rappich, J.; Nickel, N. H. [Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Institute for Silicon Photovoltaics, Kekuléstr. 5, 12489 Berlin (Germany); Klaus, M.; Genzel, Ch. [Department of Microstructure and Residual Stress Analysis, Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Albert-Einstein-Straße 15, 12489 Berlin (Germany); Janietz, S. [Department of Polymer Electronics, Fraunhofer Institute for Applied Polymer Research, Geiselbergstr. 69, 14476 Potsdam (Germany); Frisch, J.; Koch, N. [Humboldt Universität zu Berlin, Brook-Taylor-Straße 6, 12489 Berlin (Germany)

    2015-11-16

    The influence of ether groups in the side chain of spin coated regioregular polythiophene derivatives on the polymer layer formation and the hybrid solar cell properties was investigated using electrical, optical, and X-ray diffraction experiments. The polymer layers are of high crystallinity but the polymer with 3 ether groups in the side chain (P3TOT) did not show any vibrational fine structure in the UV-Vis spectrum. The presence of ether groups in the side chains leads to better adhesion resulting in thinner and more homogeneous polymer layers. This, in turn, enhances the electronic properties of the planar c-Si/poly-thiophene hybrid solar cell. We find that the power conversion efficiency increases with the number of ether groups in the side chains, and a maximum power conversion efficiency of η = 9.6% is achieved even in simple planar structures.

  3. Cardiologic side effects of psychotropic drugs

    Institute of Scientific and Technical Information of China (English)

    Giuseppe Marano; Gianandrea Traversi; Enrico Romagnoli; Valeria Catalano; Marzia Lotrionte; Antonio Abbate; Giuseppe Biondi-Zoccai; Marianna Mazza

    2011-01-01

    Psychotropic drugs can produce cardiovascular side effects associated with a degree of cardiotoxicity.The coexistence of a heart disease complicates the management of mental illness,can contribute to a reduced quality of life and a worse illness course.The co-occurrence of psychiatric disorders in cardiac patients might affect the clinical outcome and morbidity.Moreover,the complex underlying mechanism that links these two conditions remains unclear.This paper discusses the known cardiovascular complications of psychotropic drugs and analyzes the important implications of antidepressive treatment in patients with previous cardiac history.

  4. The Other Side of GDP Growth

    Institute of Scientific and Technical Information of China (English)

    Zhan Yong; Cai Fang

    2011-01-01

    @@ THE rise of China's GDP ranking has not only led the world to rediscover China, but also reminded China to examine its own development.Both sides of the issue should be considered. On the one hand, China topping Japan [the world's previous second largest economy] in terms of GDP marks the rising of Chinas economic status, which is a milestone in the modern world economic history since Japan replaced the former Federal Republic of Germany as the world's second largest economy in 1968.

  5. Side chain polysiloxanes with phthalocyanine moieties

    Directory of Open Access Journals (Sweden)

    T. Ganicz

    2012-05-01

    Full Text Available Side chain polysiloxane with 5-(pentyloxy-3-methyloxy-9,10,16,17,23,24-hexakis(octenyloxyphthalocyanine moieties is synthesized by hydrosilylation reaction. The phase behavior and thermooptical properties of the polysiloxane and starting 2-(pent-4-enyloxy-3-methyloxy-9,10,16,17,23,24-hexakis(octenyloxyphthalocyanine is examined by POM (Polarizing optical microscopy, TOA (thermooptical analysis, DSC (differential scanning calorimetry, AFM (atomic force microscopy and SAXS (small angle X-ray scattering studies. The effect of the attachment of phthalocyanine to polysiloxane chains over phase transitions and phase morphology is discussed in details.

  6. COMMUNICATIONS GROUP

    CERN Multimedia

    L. Taylor

    2010-01-01

    The recently established CMS Communications Group, led by Lucas Taylor, has been busy in all three of its main are areas of responsibility: Communications Infrastructure, Information Systems, and Outreach and Education Communications Infrastructure The damage caused by the flooding of the CMS Centre@CERN on 21st December has been completely repaired and all systems are back in operation. Major repairs were made to the roofs, ceilings and one third of the floor had to be completely replaced. Throughout these works, the CMS Centre was kept operating and even hosted a major press event for first 7 TeV collisions, as described below. Incremental work behind the scenes is steadily improving the quality of the CMS communications infrastructure, particularly Webcasting, video conferencing, and meeting rooms at CERN. CERN/IT is also deploying a pilot service of a new videoconference tool called Vidyo, to assess whether it might provide an enhanced service at a lower cost, compared to the EVO tool currently in w...

  7. COMMUNICATIONS GROUP

    CERN Multimedia

    L. Taylor

    2011-01-01

    Communications Infrastructure The 55 CMS Centres worldwide are well used by physicists working on remote CMS shifts, Computing operations, data quality monitoring, data analysis and outreach. The CMS Centre@CERN in Meyrin is particularly busy at the moment, hosting about 50 physicists taking part in the heavy-ion data-taking and analysis. Three new CMS meeting room will be equipped for videoconferencing in early 2012: 40/5B-08, 42/R-031, and 28/S-029. The CMS-TV service showing LHC Page 1, CMS Page 1, etc. (http://cmsdoc.cern.ch/cmscc/projector/index.jsp) is now also available for mobile devices: http://cern.ch/mcmstv. Figure 12: Screenshots of CMS-TV for mobile devices Information Systems CMS has a new web site: (http://cern.ch/cms) using a modern web Content Management System to ensure content and links are managed and updated easily and coherently. It covers all CMS sub-projects and groups, replacing the iCMS internal pages. It also incorporates the existing CMS public web site (http:/...

  8. COMMUNICATIONS GROUP

    CERN Multimedia

    L. Taylor

    2012-01-01

      Outreach and Education We are fortunate that our research has captured the public imagination, even though this inevitably puts us under the global media spotlight, as we saw with the Higgs seminar at CERN in December, which had 110,000 distinct webcast viewers. The media interest was huge with 71 media organisations registering to come to CERN to cover the Higgs seminar, which was followed by a press briefing with the DG and Spokespersons. This event resulted in about 2,000 generally positive stories in the global media. For this seminar, the CMS Communications Group prepared up-to-date news and public material, including links to the CMS results, animations and event displays [http://cern.ch/go/Ch8thttp://cern.ch/go/Ch8t]. There were 44,000 page-views on the CMS public website, with the Higgs news article being by far the most popular item. CMS event displays from iSpy are fast becoming the iconic media images, featuring on numerous major news outlets (BBC, CNN, MSN...) as well as in the sci...

  9. Waste heat conducting system for side burner regenerative coke oven batteries with divided heating system. [German Patent

    Energy Technology Data Exchange (ETDEWEB)

    Thiersch, F.; Strobel, M.; Schmitz, T.

    1980-08-21

    In the well known waste heat removal system for side burner regenerative coking over batteries with divided heating system both flues could be used simultaneously and equally. The flues in the longitudinal direction of the battery open into a common chimney foot connection at one end of the battery. They are individually connected via opposite groups of transverse flues to opposite groups of waste heat elbows of waste heat valves on the machine and on the coke side.

  10. Greenhouse gas emission mitigation in the Sri Lanka power sector supply side and demand side options

    Energy Technology Data Exchange (ETDEWEB)

    Wijayatunga, P.D.C. [University of Moratuwa (Sri Lanka). Centre for Energy Studies; Fernando, W.J.L.S. [Sri Lanka Energy Managers Association, Colombo (Sri Lanka); Shrestha, R.M. [Asian Inst. of Technology, Pathumthani (Thailand). Energy Program

    2003-12-01

    Sri Lanka has had a hydropower dominated electricity generation sector for many years with a gradually decreasing percentage contribution from hydroresources. At the same time, the thermal generation share has been increasing over the years. Therefore, the expected fuel mix in the future in the large scale thermal generation system would be dominated by petroleum products and coal. This will result in a gradual increase in greenhouse gas (GHG) and other environmental emissions in the power sector and, hence, require special attention to possible mitigation measures. This paper analyses both the supply side and demand side (DSM) options available in the Sri Lanka power sector in mitigating emissions in the sector considering the technical feasibility and potential of such options. Further, the paper examines the carbon abatement costs associated with such supply side and DSM interventions using an integrated resource planning model, which is not used in Sri Lanka at present. The sensitivities of the final generation costs and emissions to different input parameters, such as discount rates, fuel prices and capital costs, are also presented in the paper. It is concluded that while some DSM measures are economically attractive as mitigation measures, all the supply side options have a relatively high cost of mitigation, particularly in the context of GHG emission mitigation. Further it is observed that when compared with the projected price of carbon under different global carbon trading scenarios, these supply side options cannot provide economically beneficial CO{sub 2} mitigation in countries like Sri Lanka. (author)

  11. Greenhouse gas emission mitigation in the Sri Lanka power sector supply side and demand side options

    International Nuclear Information System (INIS)

    Sri Lanka has had a hydropower dominated electricity generation sector for many years with a gradually decreasing percentage contribution from hydroresources. At the same time, the thermal generation share has been increasing over the years. Therefore, the expected fuel mix in the future in the large scale thermal generation system would be dominated by petroleum products and coal. This will result in a gradual increase in greenhouse gas (GHG) and other environmental emissions in the power sector and, hence, require special attention to possible mitigation measures. This paper analyses both the supply side and demand side (DSM) options available in the Sri Lanka power sector in mitigating emissions in the sector considering the technical feasibility and potential of such options. Further, the paper examines the carbon abatement costs associated with such supply side and DSM interventions using an integrated resource planning model, which is not used in Sri Lanka at present. The sensitivities of the final generation costs and emissions to different input parameters, such as discount rates, fuel prices and capital costs, are also presented in the paper. It is concluded that while some DSM measures are economically attractive as mitigation measures, all the supply side options have a relatively high cost of mitigation, particularly in the context of GHG emission mitigation. Further it is observed that when compared with the projected price of carbon under different global carbon trading scenarios, these supply side options cannot provide economically beneficial CO2 mitigation in countries like Sri Lanka

  12. Finite-sided deformation spaces of complete affine 3-manifolds

    CERN Document Server

    Charette, Virginie; Goldman, William M

    2011-01-01

    A Margulis spacetime is a complete affine 3-manifold M with nonsolvable fundamental group. Associated to every Margulis spacetime is a noncompact complete hyperbolic surface S. We show that every Margulis spacetime is orientable, even though S may be nonorientable. We classify Margulis spacetimes when S is homeomorphic to a two-holed cross-surface, that is, the complement of two disjoint discs in the real projective plane. We show that every such manifold is homeomorphic to a solid handlebody of genus two, and admits a fundamental polyhedron bounded by crooked planes. Furthermore, the deformation space is a bundle of convex quadrilateral cones over the space of marked hyperbolic structures. The sides of each quadrilateral cone are defined by invariants of the two boundary components and the two orientation-reversing simple curves. The two-holed cross-surface, together with the three-holed sphere, are the only topologies for which the deformation space of complete affine structures is finite-sided.

  13. Phytochemicals that counteract the cardiotoxic side effects of cancer chemotherapy

    Directory of Open Access Journals (Sweden)

    Anita Piasek

    2009-04-01

    Full Text Available Almost all clinically used antitumor drugs exhibit toxic side effects affecting heart function. Because of cardiotoxicity during anticancer chemotherapy, effective doses of cytostatics have to be limited, which may worsen antitumor efficacy. The cardiotoxicity induced by cytostatics of the anthracycline group in particular results, among others, from massive stimulation of ROS. It has therefore been suggested that some phytochemicals with high antioxidant potential, when administered together with antitumor agents, could decrease the toxic side effects of chemotherapy and reduce the risk of heart failure. This review summarizes findings of studies undertaken to identify edible plants or phytochemicals isolated from them displaying cardioprotective properties during chemotherapy. Such properties have been shown for such foods as grapes, garlic, tomato, spinach, and beetroot. A protective role on the heart is also displayed by melatonin (a hormone synthesized by the pineal gland, but also present in many edible plants, chalcones (precursors of all known flavonoids, some herbal dietary supplements, vitamins A, C, and E, selenium, and semisynthetic flavonoid 7-monohydroxyethylrutoside (monoHER. Although to date only a limited number of investigations have been carried out, their results suggest that dietary intervention with antioxidants found in edible plants may be a safe and effective way of alleviating the toxicity of anticancer chemotherapy and preventing heart failure.

  14. The Right Side of Einstein's Equation

    CERN Document Server

    Spiegel, Edward A

    2014-01-01

    Recent developments in observational cosmology have led to attempts to make modifications on both sides of the Einstein equation to explain some of the puzzling new findings. What follows is an examination of the source of gravity that we usually find on the right hand side of Einstein's equation. The outcome is a modified version of the stress-energy tensor that is the source of the gravitational field. The derivation is based on the kinetic theory of a gas of identical particles with no internal structure. The presentation here is in two parts. In Part I, I describe the stress tensor that Xinzhong Chen and I have proposed for the matter tensor for a nonrelativistic gas with input from Hongling Rao and Jean-Luc Thiffeault. Our derivation of the equations of fluid dynamics is based on kinetic theory without recourse to the standard Chapman-Enskog approximation. In Part II, I present the analogous derivation of our form for the stress-energy tensor in the relativistic case. Then I exhibit its application to th...

  15. Antilensing: the bright side of voids.

    Science.gov (United States)

    Bolejko, Krzysztof; Clarkson, Chris; Maartens, Roy; Bacon, David; Meures, Nikolai; Beynon, Emma

    2013-01-11

    More than half of the volume of our Universe is occupied by cosmic voids. The lensing magnification effect from those underdense regions is generally thought to give a small dimming contribution: objects on the far side of a void are supposed to be observed as slightly smaller than if the void were not there, which together with conservation of surface brightness implies net reduction in photons received. This is predicted by the usual weak lensing integral of the density contrast along the line of sight. We show that this standard effect is swamped at low redshifts by a relativistic Doppler term that is typically neglected. Contrary to the usual expectation, objects on the far side of a void are brighter than they would be otherwise. Thus the local dynamics of matter in and near the void is crucial and is only captured by the full relativistic lensing convergence. There are also significant nonlinear corrections to the relativistic linear theory, which we show actually underpredicts the effect. We use exact solutions to estimate that these can be more than 20% for deep voids. This remains an important source of systematic errors for weak lensing density reconstruction in galaxy surveys and for supernovae observations, and may be the cause of the reported extra scatter of field supernovae located on the edge of voids compared to those in clusters. PMID:23383886

  16. Side effects of cytokines approved for therapy.

    Science.gov (United States)

    Baldo, Brian A

    2014-11-01

    Cytokines, currently known to be more than 130 in number, are small MW (aldesleukin (rhIL-2), oprelvekin (rhIL-11), filgrastim and tbo-filgrastim (rhG-CSF), sargramostim (rhGM-CSF), metreleptin (rh-leptin) and the rh-erythropoietins, epoetin and darbepoietin alfa. Anakinra, a recombinant receptor antagonist for IL-1, is in the IL-1 family; recombinant interferons alfa-1, alfa-2, beta-1 and gamma-1 make up the interferon family; palifermin (rhKGF) and becaplermin (rhPDGF) are in the PDGF family; and rhBMP-2 and rhBMP-7 represent the TGFβ family. The main physicochemical features, FDA-approved indications, modes of action and side effects of these approved cytokines are presented. Underlying each adverse events profile is their pleiotropism, potency and capacity to release other cytokines producing cytokine 'cocktails'. Side effects, some serious, occur despite cytokines being endogenous proteins, and this therefore demands caution in attempts to introduce individual members into the clinic. This caution is reflected in the relatively small number of cytokines currently approved by regulatory agencies and by the fact that 14 of the FDA-approved preparations carry warnings, with 10 being black box warnings. PMID:25270293

  17. On flow equivalence of one-sided topological Markov shifts

    OpenAIRE

    Matsumoto, Kengo

    2015-01-01

    We introduce notions of suspension and flow equivalence on one-sided topological Markov shifts, which we call one-sided suspension and one-sided flow equivalence, respectively. We prove that one-sided flow equivalence is equivalent to continuous orbit equivalence on one-sided topological Markov shifts. We also show that the zeta function of the flow on a one-sided suspension is a dynamical zeta function with some potential function and that the set of certain dynamical zeta functions is invar...

  18. Glycan Side Reaction May Compromise ETD-Based Glycopeptide Identification

    Science.gov (United States)

    Darula, Zsuzsanna; Medzihradszky, Katalin F.

    2014-06-01

    Tris(hydroxymethyl)aminomethane (Tris) is one of the most frequently used buffer ingredients. Among other things, it is recommended and is usually used for lectin-based affinity enrichment of glycopeptides. Here we report that sialic acid, a common `capping' unit in both N- and O-linked glycans may react with this chemical, and this side reaction may compromise glycopeptide identification when ETD spectra are the only MS/MS data used in the database search. We show that the modification may alter N- as well as O-linked glycans, the Tris-derivative is still prone to fragmentation both in `beam-type' CID (HCD) and ETD experiments, at the same time—since the acidic carboxyl group was `neutralized'—it will display a different retention time than its unmodified counterpart. We also suggest solutions that—when incorporated into existing search engines—may significantly improve the reliability of glycopeptide assignments.

  19. Measles Vaccine : A Study On Seroconversion And Side Effects

    Directory of Open Access Journals (Sweden)

    Malik Abida

    1998-01-01

    Full Text Available Research Question: 1. What is the extent of immune response of Edmonston Zagreb Strain in children? 2. What are the side effects of this vaccine? Objectives: 1. To follow up children after Edmonston Zagreb strain vaccination for evaluation of seroconverstion. Study: Cross sectional Setting: Well Baby Clinic of pediatrics OPD at J.N. Medical College, A.M.U., Aigarh (U.P participants: Children between 9-15 months. Sample Size: 100 consecutive children coming for routine immunization. Study variable: Malnourished and poor socio-economic status Outcome variable: Extent of seroconversion with no statistical significant difference between malnourished and socio-economically poor children. 26% showed minor self-limiting post vaccination reactions in all age groups. Recommendations: Edmonston Zagreb measles vaccine is recommended since it has very good immunogenic activity and post vaccination reactions.

  20. Demand Side Management in non-residential buildings; Demand Side Management in Nichtwohngebaeuden

    Energy Technology Data Exchange (ETDEWEB)

    Jungwirth, Johannes [Technische Univ. Muenchen (DE). Lehrstuhl fuer Energiewirtschaft und Anwendungstechnik (IfE)

    2011-07-01

    Due to the fluctuating supply characteristics and a paradigm shift, the strong expansion of renewable energy generators expect the structure of the concept of energy supply. An integration of renewables into the electricity grid requires new ways to compensate the discrepancy between production and consumption. The implementation of a demand-side management requires an electrical load and the possibility to control consumers in response to an external signal. From this perspective, the author of the contribution under consideration reports on innovative systems for the realization of a demand-side management in non-residential buildings.

  1. Influence of Orientation of Side Ligand Group on Current Through Molecular Device

    Institute of Scientific and Technical Information of China (English)

    Chen H.; Note R.; Mizuseki H.; Kawazoe Y.

    2004-01-01

    1 Introduction The recent significant advances in the molecular electronics show that the molecular device is a good candidate with great potential as the successor to the silicon-based semi-conductors. After the successful experimental work made by Reed et al.[1] in which the single benzene molecule acts as the core of the molecular device, many experimental and theoretical investigations have been done on this subject[2-11].

  2. Aromatic polyesters with photosensitive side chains: Synthesis, characterization and properties

    Directory of Open Access Journals (Sweden)

    Nechifor Marioara

    2016-01-01

    Full Text Available New aromatic polyesters with photosensitive groups in their pendant chains were prepared from a diphenol carrying as substituent a cinnamoyl group extended with a flexible oxyethyleneoxy spacer and different aromatic dicarboxylic acids via direct polyesterification reaction in the presence of tosyl chloride/pyridine/dimethylformamide system as condensing agent. The resulting polyesters were characterized using Fourier-transform IR, proton and carbon nuclear magnetic resonance and ultraviolet spectroscopy, differential scanning calorimetry, thermogravimetric analysis, wide-angle X-ray diffractometry, gel permeation chromatography, viscosity measurement and solubility test. These polyarylates had moderate inherent viscosities ranging from 0.37 to 0.54 dL g-1, good solubility in polar aprotic solvents, and afforded transparent, colorless and apparently tough films by casting from their solutions. Their glass-transition temperatures ranged from 136 to 154°C. All of them did not show significant decomposition below 320°C and retained 38-47 % weight at 700°C in nitrogen atmosphere. The presence of cinnamoyl chromophore endowed these polymers with the ability to react to ultraviolet light which resulted in photodimerization between cinnamoyl side groups upon irradiation at l = 365 nm and cross-linking the polymers chains in the absence of photo-initiators or photo-sensitizers. As a consequence, the polymer films became insoluble in organic solvents.

  3. Narrating narcolepsy--centering a side effect.

    Science.gov (United States)

    Lundgren, Britta

    2015-01-01

    The mass-vaccination with Pandemrix was the most important preventive measure in Sweden during the A(H1N1) influenza pandemic of 2009-2010, and covered 60% of the population. From 2010, an increased incidence of the neurological disease narcolepsy was reported, and an association with Pandemrix was affirmed for more than 200 children and young adults. The parental experience of this side effect provided a starting point for a collectively shaped critical narrative to be acted out in public, but also personalized narratives of continual learning about the disease and its consequences. This didactic functionality resulted in active meaning-making practices about how to handle the aftermath--using dark humor, cognitive tricks, and making themselves and their children's bodies both objects and subjects of knowledge. Using material from interviews with parents, this mixing of knowledge work and political work, and the potential for reflective consciousness, is discussed.

  4. Industrial demand side management: A status report

    Energy Technology Data Exchange (ETDEWEB)

    Hopkins, M.F.; Conger, R.L.; Foley, T.J. [and others

    1995-05-01

    This report provides an overview of and rationale for industrial demand side management (DSM) programs. Benefits and barriers are described, and data from the Manufacturing Energy Consumption Survey are used to estimate potential energy savings in kilowatt hours. The report presents types and examples of programs and explores elements of successful programs. Two in-depth case studies (from Boise Cascade and Eli Lilly and Company) illustrate two types of effective DSM programs. Interviews with staff from state public utility commissions indicate the current thinking about the status and future of industrial DSM programs. A comprehensive bibliography is included, technical assistance programs are listed and described, and a methodology for evaluating potential or actual savings from projects is delineated.

  5. Object detection in side scan sonar

    Science.gov (United States)

    Wang, Wenwu; Cheng, Binbin; Chen, Yao

    2015-12-01

    Automatic target detection is a challenging task as the response from an underwater target may vary greatly depending on its configuration, sonar parameters and the environment. We propose a Z- test algorithm for target detection in side scan sonar image which avoids this problem that covers the variation in the target response. A Z-test is performed on the means of the pixel gray levels within and outside the window area, a detection being called when the value of test statistic feature exceeds a certain threshold. The algorithm is formulated for real-time execution on limited memory commercial-of-the-shelf platforms and is capable of detection objects on the seabed-bottom.

  6. The Siding Spring Hazard at Mars

    Science.gov (United States)

    Kelley, Michael; Bauer, James; Bodewits, Dennis; Farnham, Tony; Li, Jian-Yang; Samarasinha, Nalin; Stevenson, Rachel; Tricarico, Pasquale

    2014-02-01

    Comet C/2013 A1 (Siding Spring) will pass Mars at the extremely close distance of 136,000 km in Oct 2014, giving Mars orbiting spacecraft an up-close and unprecedented view of this dynamically new comet. However, 100 minutes after the closest approach to the nucleus, Mars passes within 30,000 km of the comet's orbit. Here, large dust grains may be found on impacting trajectories, potentially posing a fatal hazard to the spacecraft. Such large grains must be ejected from the comet nucleus well before the time of encounter. Therefore, we propose IRAC imaging of this comet to assess the present-day gas production rate, which will aid dust impact hazard assessment.

  7. The quantum capacity with symmetric side channels

    CERN Document Server

    Smith, G; Winter, A; Smith, Graeme; Smolin, John A.; Winter, Andreas

    2006-01-01

    We present an upper bound for the quantum channel capacity that is both additive and convex. Our bound can be interpreted as the capacity of a channel for high-fidelity communication when assisted by the family of all channels mapping symmetrically to their output and environment. The bound seems to be quite tight, and for degradable quantum channels it coincides with the unassisted channel capacity. Using this symmetric side channel capacity, we find new upper bounds on the capacity of the depolarizing channel. We also briefly indicate an analogous notion for distilling entanglement using the same class of (one-way) channels, yielding one of the few genuinely 1-LOCC monotonic entanglement measures.

  8. The two sides of silicon detectors

    CERN Document Server

    Devine, S R

    2001-01-01

    /p/n sup + and essentially two p-n junctions within one device. With increasing bias voltage, as the electric field is extending into the detector bulk from opposite sides of the silicon detector, there are two distinct depletion regions that collect charge signal independently. Summing the signal charge from the two regions, one is able to reconstruct the initial energy of the incident particle. From Transient Current measurements it is apparent that E-field manipulation is possible by excess carrier injection, enabling a high enough E-field to extend across the width of the detector, allowing for efficient charge collection. Results are presented on in situ irradiation of silicon detector's at cryogenic temperature. The results show that irradiation at cryogenic temperatures does not detrimentally effect a silicon detectors performance when compared to its irradiation at room temperature. Operation of silicon devices at cryogenic temperatures offers the advantage of reducing radiation-induced leakage curren...

  9. Side-Scan-Sonar Points for Hudson River, NY

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Side Scan Point Files. These points correspond to individual pings which produced hte side-scan-sonar backscatter imagery. Sonar data were collected November 6 to...

  10. NUMERICAL SIMULATION OF FLOW OVER TWO SIDE-BY-SIDE CIRCULAR CYLINDERS

    Institute of Scientific and Technical Information of China (English)

    SARVGHAD-MOGHADDAM Hesam; NOOREDIN Navid; GHADIRI-DEHKORDI Behzad

    2011-01-01

    In the present paper,the unsteady,viscous,incompressible and 2-D flow around two side-by-side circular cylinders was simulated using a Cartesian-staggered grid finite volume based method.A great-source term technique was employed to identify the solid bodies (cylinders) located in the flow field and boundary conditions were enforced by applying the ghost-cell technique.Finally,the characteristics of the flow around two side-by-side cylinders were comprehensively obtained through several computational simulations.The computational simulations were performed for different transverse gap ratios (1.5≤T/D≤4) in laminar (Re =100,200 ) and turbulent (Re =104) regimes,where T and D are the distance between the centers of cylinders and the diameter of cylinders,respectively.The Reynolds number is based on the diameter of cylinders,D.The pressure field and vorticity distributions along with the associated streamlines and the time histories of hydrodynamic forces were also calculated and analyzed for different gap ratios.Generally,different flow patterns were observed as the gap ratio and Reynolds number varied.Accordingly,the hydrodynamic forces showed irregular variations for small gaps while they took a regular pattern at higher spacing ratios.

  11. LARGE EDDY SIMULATION AND SPECTRUM ANALYSIS OF FLOW AROUND TWO SQUARE CYLINDERS ARRANGED SIDE BY SIDE

    Institute of Scientific and Technical Information of China (English)

    魏英杰; 朱蒙生; 何钟怡

    2004-01-01

    Large eddy simulation cooperated with the second order full extension ETG (Euler-Taylor-Galerkin) finite element method was applied to simulate the flow around two square cylinders arranged side by side at a spacing ratio of 1.5. The second order full extension ETG finite element method was developed by Wang and He. By means of Taylor expansion of terms containing time derivative, time derivative is replaced by space derivative. The function of it is equal to introducing an artificial viscosity term. The streamlines of the flow at different moments were obtained. The time history of drag coefficient, lift coefficient and the streamwise velocity on the symmetrical points were presented. Furthermore, the symmetrical problem of the frequency spectrum of flow around two square cylinders arranged side by side were studied by using the spectral analysis technology. The data obtained at the initial stage are excluded in order to avoid the influence of initial condition on the results. The power spectrums of drag coefficient, lift coefficient, the streamwise velocity on the symmetrical points were analyzed respectively.The results show that although the time domain process of dynamic parameters is nonsymmetrical, the frequency domain process of them is symmetrical under the symmetrical boundary conditions.

  12. Quantitative flow characteristics for side-by-side square cylinders via PIV

    Directory of Open Access Journals (Sweden)

    Dogan Sercan

    2012-04-01

    Full Text Available In this study, instantaneous and time-averaged flow structures downstream of the sharp-edged single and two and three side-by-side square cylinders (SCs immersed in a uniform open channel water flow were studied by a technique of particle image velocimetry (PIV. Experimental results of wake flow structures were presented for gap ratios (G/D in the range of 1.0”G/D”3.0 for Reynolds number values of 1050, 2450 and 3400. Flow structures depending on the square cylinder (SC configurations and Reynolds number were discussed. It has been found that the development of the vortex shedding as well as the flow structure were substantially altered for side-by-side SCs comparing to the single SC. Asymmetrical and biased wake structures were observed because of the jetlike flow between the SCs for two SCs cases for the gap ratio less than 2.0. Depending on the gap spacing between the SCs, the interaction results of time2 averaged vorticity, velocity vector field, Reynolds stress correlations and streamline patterns in the wake region form a distinguished flow structure. Strouhal numbers for the single square cylinder for 1050≤Re≤3400 are found in the range of 0.12-0.13. The present results have supported the previous works by providing detailed quantitative experimental information with PIV in the wake region of the SC and might be helpful for validation of numerical studies and designers.

  13. Effects of rotational side preferences on immobile behavior of normal mice in the forced swimming test.

    Science.gov (United States)

    Krahe, Thomas E; Filgueiras, Claudio C; Schmidt, Sergio L

    2002-01-01

    It has been suggested that side preferences in spontaneous rotational behavior are determinant of differences in vulnerability to the effects of the learned helplessness paradigm. The purpose of the present study was to investigate the effects of side preferences of rotational behavior in another animal model of depression, the forced swimming test. Immobility was also investigated upon repeated testing sessions and in interaction with sex. Swiss mice (69 males and 73 females) were submitted to three sessions (test time = 5 min) of forced swimming. Immobile and turning behaviors were measured for each session and within each testing session. Consistency of laterality was defined considering the persistence of the same side turning preference in the three sessions. In general, there was an increase in immobility as test progressed and upon repeated testing sessions. Marked interindividual differences in mice immobile behavior were observed when consistency of laterality was considered. Consistent-right-turners presented greater immobility in the first session and better test-retest reliability, indicating that for this group, the adoption of immobile behavior was faster and more reliable over time. Immobility was higher for side-consistent males than for side-consistent females in the first session. This difference became even greater when consistent-right-turner males were compared to consistent-left-turner females. These results reinforce the idea that side preferences of spontaneous rotational behavior may account for interindividual differences in animal models of depression. PMID:11853109

  14. A simulator study investigating how motorcyclists approach side-road hazards.

    Science.gov (United States)

    Crundall, Elizabeth; Stedmon, Alex W; Saikayasit, Rossukorn; Crundall, David

    2013-03-01

    The most common form of motorcycle collision in the UK occurs when another road user fails to give way and pulls out from a side road in front of an oncoming motorcyclist. While research has considered these collisions from the car driver's perspective, no research to date has addressed how motorcyclists approach these potential hazards. This study conducted a detailed analysis of motorcyclist speed and road position on approach to side-roads in a simulated suburban setting. Novice, Experienced and Advanced riders rode two laps of a simulated route, encountering five side-roads on each lap. On the second lap, a car emerged from the first side-road in a typical 'looked but failed to see' accident scenario. Three Experienced riders and one Novice rider collided with the hazard. The Advanced rider group adopted the safest strategy when approaching side-roads, with a lane position closer to the centre of the road and slower speeds. In contrast, Experienced riders chose faster speeds, often over the speed limit, especially when approaching junctions with good visibility. Rider behaviour at non-hazard junctions was compared between laps, to investigate if riders modified their behaviour after experiencing the hazard. Whilst all riders were generally more cautious after the hazard, the Advanced riders modified their behaviour more than the other groups after the hazard vehicle had pulled out. The results suggest that advanced training can lead to safer riding styles that are not acquired by experience alone.

  15. Chewing side, bite force symmetry, and occlusal contact area of subjects with different facial vertical patterns

    Directory of Open Access Journals (Sweden)

    Simone Guimarães Farias Gomes

    2011-10-01

    Full Text Available Craniofacial dimensions influence oral functions; however, it is not known whether they are associated with function asymmetry. The objective of this study was to evaluate chewing side preference and lateral asymmetry of occlusal contact area and bite force of individuals with different craniofacial patterns. Seventy-eight dentate subjects were divided into 3 groups according to the VERT index as follows: (1 mesofacial, (2 brachyfacial and (3 dolichofacial. Chewing side preference was evaluated using jaw tracking equipment, occlusal contact area was measured by silicon registration of posterior teeth, and bite force was measured unilaterally on molar regions using 2.25 mm-thick sensors. Statistical analysis was performed using ANOVA on Ranks, Student's t-test, and Mann-Whitney tests at a 5% significance level. Mesofacial, brachyfacial, and dolichofacial subjects presented more occlusal contact area on the left side. Only dolichofacial subjects showed lateral asymmetry for bite force, presenting higher force on the left side. No statistically significant differences were found for chewing side preference among all groups. Within the limitations of this study, it can be concluded that craniofacial dimensions play a role in asymmetry of bite force. ClinicalTrials.gov ID: NCT01286363.

  16. The demand-side management program development process: A utility perspective

    Energy Technology Data Exchange (ETDEWEB)

    Wolfe, A.K. [Oak Ridge National Lab., TN (United States); Yourstone, N.E. [Yourstone (Evelin), Albuquerque, NM (United States)

    1992-03-01

    This report describes an aspect of DSM that has received little attention, namely, how utilities develop DSM programs. The selection of utilities to study purposely was biased in favor of those with reputations for being experienced DSM program developers so as to optimize the chances to obtain detailed information. The DSM planning process is affected by organizational factors and external influences: (1) the location of the demand-side planning department within the utility; (2) the demand-side planning group`s functional responsibilities; (3) upper management participation in the DSM program development process; and (4) the organizational relationship between (or, separation of) supply-side and demand-side planning. Organizational factors reflect utilities` views of DSM programs and thus can affect the adoption of a technology- or customer-oriented approach. Despite repeated claims of the uniqueness of the demand- side planning process and its resistance to standardization, two general approaches to program development were discerned, namely technology- or customer-orientation. Although utilities consider customer related and technological factors in their DSM program development process, utilities can be differentiated by their emphasis on one or the other approach. 25 refs.

  17. Organizational mediators siding with or against the powerful party?

    NARCIS (Netherlands)

    C.K.W. de Dreu; P. Laskewitz; E. van de Vliert

    1994-01-01

    Examined whether, instead of being impartial, a mediator may side with one party as a function of the disputants' power differences (power balancing theory), the mediator's legitimacy judgments (siding theory), or the disputants' capacity to sanction the mediator (siding theory). A questionnaire stu

  18. Market definition in two-sided markets : Theory and practice

    NARCIS (Netherlands)

    Filistrucchi, L.; Geradin, D.A.A.G.; van Damme, E.E.C.; Affeldt, P.

    2014-01-01

    Drawing from the economics of two-sided markets, we provide suggestions for the definition of the relevant market in cases involving two-sided platforms, such as media outlets, online intermediaries, payment cards companies, and auction houses. We also discuss when a one-sided approach may be harmle

  19. Arginine side chain interactions and the role of arginine as a gating charge carrier in voltage sensitive ion channels

    Science.gov (United States)

    Armstrong, Craig T.; Mason, Philip E.; Anderson, J. L. Ross; Dempsey, Christopher E.

    2016-02-01

    Gating charges in voltage-sensing domains (VSD) of voltage-sensitive ion channels and enzymes are carried on arginine side chains rather than lysine. This arginine preference may result from the unique hydration properties of the side chain guanidinium group which facilitates its movement through a hydrophobic plug that seals the center of the VSD, as suggested by molecular dynamics simulations. To test for side chain interactions implicit in this model we inspected interactions of the side chains of arginine and lysine with each of the 19 non-glycine amino acids in proteins in the protein data bank. The arginine guanidinium interacts with non-polar aromatic and aliphatic side chains above and below the guanidinium plane while hydrogen bonding with polar side chains is restricted to in-plane positions. In contrast, non-polar side chains interact largely with the aliphatic part of the lysine side chain. The hydration properties of arginine and lysine are strongly reflected in their respective interactions with non-polar and polar side chains as observed in protein structures and in molecular dynamics simulations, and likely underlie the preference for arginine as a mobile charge carrier in VSD.

  20. Wang linker free of side reactions.

    Science.gov (United States)

    Castro, Vida; Rodriguez, Hortensia; Albericio, Fernando

    2013-01-18

    A new resin for the solid-phase synthesis of peptide acids was developed. It was based on a linker with two unique features: methoxy groups as the only activating groups of the phenyl ring and a copper(I)-catalyzed Click chemistry reaction to anchor it to the solid support. The efficiency of this new resin in solid phase peptide synthesis was compared with that of Wang resin.

  1. 7 CFR 29.1164 - Cutters (C Group).

    Science.gov (United States)

    2010-01-01

    ... just below the midportion of the stalk. Leaves of the C group have a tendency to roll concealing the... over 10 percent may be waste. C5LP—Low Quality Lemon Cutters (Primings Side) Prematurely ripe, open... over 10 percent may be waste. C5FP—Low Quality Orange Cutters (Primings Side) Prematurely ripe,...

  2. Flow and wall shear stress in end-to-side and side-to-side anastomosis of venous coronary artery bypass grafts

    Directory of Open Access Journals (Sweden)

    Poulikakos Dimos

    2007-09-01

    Full Text Available Abstract Purpose Coronary artery bypass graft (CABG surgery represents the standard treatment of advanced coronary artery disease. Two major types of anastomosis exist to connect the graft to the coronary artery, i.e., by using an end-to-side or a side-to-side anastomosis. There is still controversy because of the differences in the patency rates of the two types of anastomosis. The purpose of this paper is to non-invasively quantify hemodynamic parameters, such as mass flow and wall shear stress (WSS, in end-to-side and side-to-side anastomoses of patients with CABG using computational fluid dynamics (CFD. Methods One patient with saphenous CABG and end-to-side anastomosis and one patient with saphenous CABG and side-to-side anastomosis underwent 16-detector row computed tomography (CT. Geometric models of coronary arteries and bypasses were reconstructed for CFD analysis. Blood flow was considered pulsatile, laminar, incompressible and Newtonian. Peri-anastomotic mass flow and WSS were quantified and flow patterns visualized. Results CFD analysis based on in-vivo CT coronary angiography data was feasible in both patients. For both types of CABG, flow patterns were characterized by a retrograde flow into the native coronary artery. WSS variations were found in both anastomoses types, with highest WSS values at the heel and lowest WSS values at the floor of the end-to-side anastomosis. In contrast, the highest WSS values of the side-to-side anastomosis configuration were found in stenotic vessel segments and not in the close vicinity of the anastomosis. Flow stagnation zones were found in end-to-side but not in side-to-side anastomosis, the latter also demonstrating a smoother stream division throughout the cardiac cycle. Conclusion CFD analysis of venous CABG based on in-vivo CT datasets in patients was feasible producing qualitative and quantitative information on mass flow and WSS. Differences were found between the two types of anastomosis

  3. 49 CFR 231.8 - Tank cars without side sills and tank cars with short side sills and end platforms.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Tank cars without side sills and tank cars with... APPLIANCE STANDARDS § 231.8 Tank cars without side sills and tank cars with short side sills and end platforms. (a) Hand brakes—(1) Number. Same as specified for “Box and other house cars” (see §...

  4. Side effects of antiviral therapy in patients with chronic hepatitis C infection

    Directory of Open Access Journals (Sweden)

    Kostić Velimir

    2012-01-01

    Full Text Available Introduction. Chronic hepatitis C currently represents a global health problem, which is expected to be reduced by pegylated-interferon and ribavirin therapy. Material and Methods. We examined 88 patients with chronic hepatitis C, divided into three groups according to their comorbidity: the patients without comorbidity were in group I, group II included the patients on dialysis, and group III included the patients with hemophilia. Results. A significant difference was found in the percentage of achieved sustained virological response between the patients on dialysis and other patients, p<0.05. Having analyzed the therapy adverse effects, we observed a significantly higher decrease of erythrocytes count, hemoglobin and hematocrit levels in dialysis patients compared to others (p<0.01. The patients on hemodialysis predominantly had anemia and leukopenia, while thrombocytopenia was equally present in all groups. The dominant clinical side effect was flu-like syndrome, present in more than a half of patients. Discussion. The therapy positive effect is usually accompanied with adverse effects. The lowest therapeutic response was recorded in group II, due to the virus genotype 1. A significant decrease in hematological parameters was determined in all patients. The most common clinical adverse effect was flu-like syndrome, later manifestations included: weight loss, alopecia, insomnia and irritability. Side effects like psychosis, thyroid gland dysfunction or psoriasis were not recorded. Conclusion. A significant decrease in the value of all these hematological parameters was found in all groups of patients. Clinical side effects were present in 60% of patients. Side effects did not lead to discontinuation of therapy, but only to modification of drug doses.

  5. Preparation of Novel Side-chain Pseudopolyrotaxanes Consisting of Cucurbituril[6] and Polyamine Salts

    Institute of Scientific and Technical Information of China (English)

    Zhao Sheng HOU; Ye Bang TAN; Kimoon KIM; Qi Feng ZHOU

    2005-01-01

    Pseudorotaxane monomer (VBCB) containing cucurbitutil[6] (CB[6]) and N1-(4-vinylbenzyl)-1,4-diaminobutane dihydrochloride (VBDADC) is obtained by self-assembly of cucurbituril[6] with VBDADC in water and then polymerized using potassium persulfate (KPS) as initiator to give novel water-soluble side-chain cucurbituril[6]-based pseudopolyr1o taxane (PVBCB). The chemical structures of PVBCB, VBCB and VBDADC are confirmed by H NMR,13C NMR spectra and elemental analysis. In VBCB, CB[6] is localized aliphatic group of the side chain and the molar ratio of CB[6] to VBDAC is 1:1.

  6. Radiative models for the furnace side of a bottom-fired reformer

    Energy Technology Data Exchange (ETDEWEB)

    Farhadi, F. [Chemical and Petroleum Engineering Department, Sharif University of Technology, Tehran 11365-9465 (Iran, Islamic Republic of)]. E-mail: farhadi@sharif.edu; Bahrami Babaheidari, M. [Chemical and Petroleum Engineering Department, Sharif University of Technology, Tehran 11365-9465 (Iran, Islamic Republic of); Motamed Hashemi, M.M.Y. [Chemical and Petroleum Engineering Department, Sharif University of Technology, Tehran 11365-9465 (Iran, Islamic Republic of)

    2005-10-01

    Two different groups of radiative models are used to simulate a Midrex reformer. The modeling includes the furnace-side as well as the reactor-side equations. The simultaneous solution of governing equations provides the flue gas and tube wall temperature profiles. These are compared with literature and plant data. It was observed that the Flux model, applied in this work on the furnace of a bottom-fired reformer, shows a good agreement with observed plant data. The well-stirred model is still satisfactory but the long-furnace model is far away to merit an attention.

  7. Radiative models for the furnace side of a bottom-fired reformer

    International Nuclear Information System (INIS)

    Two different groups of radiative models are used to simulate a Midrex reformer. The modeling includes the furnace-side as well as the reactor-side equations. The simultaneous solution of governing equations provides the flue gas and tube wall temperature profiles. These are compared with literature and plant data. It was observed that the Flux model, applied in this work on the furnace of a bottom-fired reformer, shows a good agreement with observed plant data. The well-stirred model is still satisfactory but the long-furnace model is far away to merit an attention

  8. Hyperprolactinaemia - a risperidone side-effect.

    Science.gov (United States)

    Grahovac, Tanja; Ruzić, Klementina; Medved, Paola; Pavesić-Radonja, Aristea; Dadić-Hero, Elizabeta

    2010-03-01

    A 47 year old patient has been treated for psychotic depression for the last 5 years. The illness began manifesting through the symptoms of depressive thoughts, intrapsychic tension, projectivity, derealisation phenomena and pre-psychotic fears. She was treated with a combination of antidepressives, anxiolitics and hypnotics in ambulatory conditions. The therapy applied did not obtain the effects expected due to which an atypical antipsychotic was administered subsequently - risperidone, a 2 mg dose in the evening. After commencing the antipsychotic treatment, the symptoms started to weaken and a steady remission was obtained. Two years after a regular risperidone administration (in combination with fluoxetine, alprazolam and flurazepam) the patient reported some "bleeding" in October 2006. Hormonal blood tests were performed and high prolactin values were registered (2567.0 mIJ/L),due to which a gradual risperidone retractement was indicated. Medicamentous hyperprolactinaemia is a well known side effect of risperidone. A gradual risperidone retractement lead to a lowered and normal prolactin level within a month. PMID:20305606

  9. The Darker Side of the Renaissance

    Directory of Open Access Journals (Sweden)

    Walter Mignolo

    2009-01-01

    Full Text Available The Darker Side of the Renaissance focuses on coloniality rather than on Europe’s witch and alchemist hunt. Today I would dare to say also that this expression refers us to the historical foundation of coloniality. At the same time, coloniality statement is called into question, as well as the distinction between the known object and the knowing subject, an assumption on which the Eurocentric project of “modernity” and “modernization” disciplines lie. The preface marks the enunciation with which the statement is stated. That is, it rejects the "point zero epistemology" denounced by Santiago Castro-Gómez. This means the reader should be always pay attention to the ennunciation s/he states him/herself, to the hand drawing the hand. Those of us dwelling at Abya-Yala/America are surrounded by the historical foundation of modernity/coloniality, we are a living part of that process, which only “scientific” alignment can make us believe we are looking at something (e.g., colonization touching what we are today

  10. Dynamic model for automotive side impact crashes

    Science.gov (United States)

    Sun, Ludong; Taghvaeeyan, Saber; Rajamani, Rajesh

    2014-07-01

    A rigid body model to represent a side impact crash is constructed using five degrees-of-freedom (dof) for the vehicle and three dof for each occupant in the vehicle. Nonlinear stiffness and damping elements and the presence of physical gaps between several components make the model highly nonlinear. The model is validated using experimental crash test data from a National Highway Traffic Safety Administration (NHTSA) database. To simplify the parameter identification process and reduce the number of parameters to be identified at each stage, a two-step process is adopted in which the vehicle is first assumed to be unaffected by the presence of the occupants, and its model parameters are identified. Subsequently, the parameters in the occupant models are identified. The active set method with a performance index that includes both the L2 and L∞ norms is used for parameter identification. A challenge is posed by the fact that the optimisation problem involved is non-convex. To overcome this challenge, a large set of random initial values of parameter estimates is generated and the optimisation method is applied with all these initial conditions. The values of parameters that provide the minimal performance index from the entire set of initial conditions are then chosen as the best parameter values. The optimal parameters values thus identified are shown to significantly improve the match between the model responses and the experimentally measured sensor signals from the NHTSA crash test.

  11. The Dark side of World of Warcraft

    DEFF Research Database (Denmark)

    Larsen, Lasse Juel

    understand, perceive or conceptualise fellow players in-side the game world. The analysis of ‘the other’ in WoW rests upon Jean-Paul Sartre’s phenomenological description of ‘the other’ through ‘the look’ in Being and Nothingness (1992). According to Sartre do living beings become aware of themselves through...... as embedded in architectural layout of game world. The ‘look’ of the other can emanate from buildings as Sartre points out in Being and Nothingness or as Michel Foucault teaches us in Discipline and Punish (1995) when he describes how ‘the look’ works as a social disciplining power embedded...... in the architectural design or as this paper argues in the spatial design of WoW. The analysis of ‘the look’ embedded in the spatial design of WoW’s game world and how it influences players perception of each other rests on Foucault’s epistemological insights. The juxtaposition of Sartre’s phenomenology and Foucault...

  12. Cardiovascular side effects of psychopharmacologic therapy.

    Science.gov (United States)

    Potočnjak, Ines; Degoricija, Vesna; Vukičević Baudoin, Dina; Čulig, Josip; Jakovljević, Miro

    2016-09-15

    WHO defined in 1976 psychopharmaca as drugs affecting psychological functions, behaviour and self-perception. Psychopharmacology is the study of pharmacological agents that affect mental and emotional functions. Creative approach to psychopharmacotherapy reflects a transdisciplinary, integrative and person-centered psychiatry. Psychiatric disorders often occur in cardiac patients and can affect the clinical presentation and morbidity. Cardiovascular (CV) side effects (SE) caused by psychopharmaceutic agents require comprehensive attention. Therapeutic approach can increase placebo and decrease nocebo reactions. The main purpose of this review is to comprehend CV SE of psychotropic drugs (PD). Critical overview of CV SE of PD will be presented in this review. Search was directed but not limited to CV effects of psychopharmacological substances, namely antipsychotics, anxiolytics, hypnotics, sedatives, antidepressants and stimulants. Literature review was performed and data identified by searches of Medline and PubMed for period from 2004 to 2015. Only full articles and abstracts published in English were included. SE of PD are organized according to the following types of CV effects: cardiac and circulatory effects, abnormalities of cardiac repolarisation and arrhythmias and heart muscle disease. There is wide spectrum and various CV effects of PD. Results of this review are based on literature research. The reviewed data came largely from prevalence studies, case reports, and cross-sectional studies. Psychopharmacotherapy of psychiatric disorders is complex and when concomitantly present with CV disease, presentation of drug SEs can significantly contribute to illness course. Further development of creative psychopharmacotherapy is required to deal with CV effects of PD. PMID:27352209

  13. Hybrid Client Side Phishing Websites Detection Approach

    Directory of Open Access Journals (Sweden)

    Firdous Kausar

    2014-08-01

    Full Text Available Phishing tricks to steal personal or credential information by entering victims into a forged website similar to the original site, and urging them to enter their information believing that this site is legitimate. The number of internet users who are becoming victims of phishing attacks is increasing beside that phishing attacks have become more sophisticated. In this paper we propose a client-side solution to protect against phishing attacks which is a Firefox extension integrated as a toolbar that is responsible for checking whether recipient website is trusted or not by inspecting URLs of each requested webpage. If the site is suspicious the toolbar is going to block it. Every URL is evaluated corresponding to features extracted from it. Three heuristics (primary domain, sub domain, and path and Naïve Bayes classification using four lexical features combined with page ranking received from two different services (Alexa, and Google page rank used to classify URL. The proposed method requires no server changes and will prevent internet users from fraudulent sites especially from phishing attacks based on deceptive URLs. Experimental results show that our approach can achieve 48% accuracy ratio using a test set of 246 URL, and 87.5% accuracy ratio by excluding NB addition tested over 162 URL.

  14. [The democratic side of science-fiction].

    Science.gov (United States)

    Lecellier, Charles-Henri

    2011-04-01

    Suspicion towards technological advances has progressively grown during the xx(th) century. However, in the XXI(st) century, reading the NBIC (nanotechnology, biotechnology, information technology and cognitive science) report of the National Science Foundation, we can note that science has caught up with science fiction. These changes in public mentality on one side and in scientific capacities on the other argue for an evolution of the debate on sciences. The recent example of the national debate on nanotechnology in France has clearly shown that the public is no longer waiting for additional sources of scientific knowledge but rather waiting for the recognition of its authority to participate in the definition of the national R&D priority and associated scientific strategies. This is all the more legitimate that these strategies will have profound impact on the future of our societies and therefore cannot be decided only by scientists. Hence, it is crucial to identify innovative tools promoting debate on sciences and their technological spin-off. Here, we contend that science fiction has major assets that could face this challenge and facilitate the dialogue between sciences and society.

  15. Comparison of side effects in myelography with iopamidol and metrizamide

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Yong; Kang, Heung Sik; Chang, Kee Hyun; Han, Seoul Heui; Kwon, Oh Sung; Myung, Ho Gin [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    1986-12-15

    The study was conducted to compare the side effects in myelography of the two non-ionic water-soluble contrast medias, lopamidol (Niopam) and Metrizamide (Amipaque). A total of 111 patients were examined, 64 with lopamidol and 47 with Metrizamide. Side effects consisted of headache, nausea, vomiting, dizziness, urinary difficulty, muscular pain, seizure, neurobehavioral disturbance, neurological sign change, vital sign change and etc. The common side effects were headache, nausea, vomiting and dizziness in order of frequency. Most of the side effects were subsided within 24 hours following myelography. lopamidol myelography caused fewer and milder side effects than Metrizamide study. The side effects were more commonly observed in cervical, thoracic or total myelography than in lumbar myelography with either lopamidol or Metrizamide. There was no significant correlation between incidence of the side effects and premedication with phenobarbital or valium injection before myelography and CSF sampling during the procedure.

  16. Patient satisfaction and side effects in primary care: An observational study comparing homeopathy and conventional medicine

    Directory of Open Access Journals (Sweden)

    Thurneysen André

    2008-09-01

    Full Text Available Abstract Background This study is part of a nationwide evaluation of complementary medicine in Switzerland (Programme Evaluation of Complementary Medicine PEK and was funded by the Swiss Federal Office of Public Health. The main objective of this study is to investigate patient satisfaction and perception of side effects in homeopathy compared with conventional care in a primary care setting. Methods We examined data from two cross-sectional studies conducted in 2002–2003. The first study was a physician questionnaire assessing structural characteristics of practices. The second study was conducted on four given days during a 12-month period in 2002/2003 using a physician and patient questionnaire at consultation and a patient questionnaire mailed to the patient one month later (including Europep questionnaire. The participating physicians were all trained and licensed in conventional medicine. An additional qualification was required for medical doctors providing homeopathy (membership in the Swiss association of homeopathic physicians SVHA. Results A total of 6778 adult patients received the questionnaire and 3126 responded (46.1%. Statistically significant differences were found with respect to health status (higher percentage of chronic and severe conditions in the homeopathic group, perception of side effects (higher percentage of reported side effects in the conventional group and patient satisfaction (higher percentage of satisfied patients in the homeopathic group. Conclusion Overall patient satisfaction was significantly higher in homeopathic than in conventional care. Homeopathic treatments were perceived as a low-risk therapy with two to three times fewer side effects than conventional care

  17. Interface Oscillation in the Side-by-Side (SBS) Tape Casting of Functionally Graded Ceramics (FGCs)

    DEFF Research Database (Denmark)

    Jabbari, Masoud; Bulatova, Regina; Hattel, Jesper Henri;

    2012-01-01

    slurries. The rheological behavior of the slurries are extracted from experiments and used in the ANSYS FLUENT commercial code to develop a fluid flow model for the non-Newtonian ceramic slurries and evaluate the interface oscillation between the stripes in SBS tape casting. The Numerical results show......Room temperature magnetic refrigeration is a new highly efficient and environmentally protective technology. Although it has not been maturely developed, it shows great applicable prosperity and seems to be a potential substitute for the traditional vapor compression technology. Tape Casting is a...... common process in producing multilayer ceramics, which now is used for producing side-by-side (SBS) functionally graded ceramics (FGCs). These FGCs are mostly used in the magnetic refrigeration sectors due to the varying composition of the magnetocaloric materials so that the magnetic transition...

  18. SIDE-BY-SIDE TESTS OF DIFFERENTLY DESIGNED EVACUATED TUBULAR COLLECTORS

    DEFF Research Database (Denmark)

    Fan, Jianhua; Dragsted, Janne; Furbo, Simon

    2007-01-01

    Six differently designed evacuated tubular collectors, ETCs, utilizing solar radiation from all directions, have been investigated experimentally. The evacuated tubular solar collectors investigated include one SLL all-glass ETC from Tshinghua Solar Co., four heat pipe ETCs from Sunda Technolgoy Co....... and one all-glass ETC with heat pipe from Exoheat AB. The collectors have been investigated side-by-side in an outdoor test facility for a long period. During the measurements, the operating conditions – such as weather conditions, inlet and mean solar collector fluid temperatures have been the same. Thus...... a direct performance comparison is possible. The results of the measurements will be presented in this paper. Among other things, the influence on the thermal performance of the absorber design will be explained. Further, it will be illustrated how the thermal performances of the different collector types...

  19. Side by side tests of two SDHW systems with solar collectors with and without antireflection treatment

    DEFF Research Database (Denmark)

    Kong, Weiqiang; Han, Jiangong; Perers, Bengt;

    2015-01-01

    Two low flow SDHW systems based on mantle tanks are tested side by side in a laboratory test facility for solar heating systems under the same weather and operation conditions. The systems are identical with the exception that one system is equipped with a solar collector with antireflection...... agreement between measured and calculated thermal performances for both systems. The extra thermal performance of the system with the solar collector with the anti reflection treated glass cover is a strong function of the solar fraction. In sunny periods with high solar fractions the percentage extra...... treated glass while the other system has a collector with a normal glass. Measurements of the thermal performance of the two systems have been carried out for a long measuring period. The thermal performances of the systems have also been calculated with a detailed simulation model. There is a good...

  20. Detection of Left-Sided and Right-Sided Hearing Loss via Fractional Fourier Transform

    Directory of Open Access Journals (Sweden)

    Shuihua Wang

    2016-05-01

    Full Text Available In order to detect hearing loss more efficiently and accurately, this study proposed a new method based on fractional Fourier transform (FRFT. Three-dimensional volumetric magnetic resonance images were obtained from 15 patients with left-sided hearing loss (LHL, 20 healthy controls (HC, and 14 patients with right-sided hearing loss (RHL. Twenty-five FRFT spectrums were reduced by principal component analysis with thresholds of 90%, 95%, and 98%, respectively. The classifier is the single-hidden-layer feed-forward neural network (SFN trained by the Levenberg–Marquardt algorithm. The results showed that the accuracies of all three classes are higher than 95%. In all, our method is promising and may raise interest from other researchers.

  1. Side-by-Side Comparison of CPV Module and System Performance

    Energy Technology Data Exchange (ETDEWEB)

    Muller, Matthew; Marion, Bill; Kurtz, Sarah; Ghosal, Kanchan; Burroughs, Scott; Libby, Cara; Enbar, Nadav

    2016-07-01

    A side-by-side comparison is made between concentrator photovoltaic module and system direct current aperture efficiency data with a focus on quantifying system performance losses. The individual losses measured/calculated, when combined, are in good agreement with the total loss seen between the module and the system. Results indicate that for the given test period, the largest individual loss of 3.7% relative is due to the baseline performance difference between the individual module and the average for the 200 modules in the system. A basic empirical model is derived based on module spectral performance data and the tabulated losses between the module and the system. The model predicts instantaneous system direct current aperture efficiency with a root mean square error of 2.3% relative.

  2. Flow Features of Three Side-by-side Circular Cylinders at Low Reynolds Number

    Directory of Open Access Journals (Sweden)

    Liu Junkao

    2016-01-01

    Full Text Available In order to study the fluctuation of kinetic parameter of cylinder matrix in incompressible stationary flow, the flow fluid around three side-by-side circular cylinders are simulated using Immersed Boundary–Lattice Boltzmann method (IB-LBM. Drag and lift force of the three cylinders are investigated as the interval between each cylinder varied from zero to five times of the cylinder diameter. Five flow patterns are defined according to the vortices structure in the downstream of the cylinders. Power spectrum analysis of lift force is developed to explain the vortex patterns. Through the research, we find the strength and phase of the gap flow play an important role in the vortex formatting process. The vortices shedding from different cylinders neutralize and combine in the near wake, contributing a lot to the variation of forces.

  3. Integrated planning in supply chains with buy-side and sell-side marketplaces

    Indian Academy of Sciences (India)

    Roshan Gaonkar; N Viswanadham

    2005-04-01

    In this paper we develop a quadratic programming model for partner selection and planning in integrated supply chain networks embedded with both sell-side and buy-side electronic marketplaces. Such a scenario arises in several practical applications. In particular, we consider a contract manufacturer who procures components from suppliers through a component marketplace and sells its manufactured sub-assemblies to original equipment manufacturers (OEMs), through a sub-assembly marketplace. In these web-enabled supply chains, embedded with upstream and downstream electronic marketplaces, we need methods for online supply-chain partner selection based on pricing and delivery schedules. In this paper, we develop and present such a model that selects partners, synchronizes supply chain activities and optimizes the profit through optimal revenue pricing and cost minimization.

  4. The odd side of torsion geometry

    DEFF Research Database (Denmark)

    Conti, Diego; Madsen, Thomas Bruun

    2014-01-01

    We introduce and study a notion of `Sasaki with torsion structure' (ST) as an odd-dimensional analogue of Kähler with torsion geometry (KT). These are normal almost contact metric manifolds that admit a unique compatible connection with 3-form torsion. Any odd-dimensional compact Lie group is sho...

  5. Bridging Inequality from Both Sides Now

    Science.gov (United States)

    Fiske, Susan T.; Molm, Linda D.

    2010-01-01

    Because inequality is one of the central concerns of sociologists, it has been addressed, in various ways, by virtually all of the major traditions of sociological social psychology--social structure and personality, symbolic interactionism, and group processes. For those who work in the social structure and personality tradition, inequality…

  6. 发电侧如何促进需求侧管理%How to Improve Demand Side Management in Generation Side

    Institute of Scientific and Technical Information of China (English)

    劳德容

    2002-01-01

    Combining with the practice of DSM in China, the paper analyzes the role of engaging demand side management in generation side. Also it deeply studies how to promote demand side management in generation side, which rarelyinvolves in the published literature all over the world. Besides, it discovers the interactions of interdependence and competition between demand side managenent and generation side operation. Lastly it studies the example of demand side management in generation side in Shenzhen.

  7. Why fruits go to the dark side

    Science.gov (United States)

    Schaefer, H. Martin

    2011-11-01

    The colours of fleshy fruits are usually attributed to attract seed dispersers to the plant. A cursory look at the gaudy colours of fleshy fruits on offer in a local fruit stall gives the impression that plants use primarily bright colours to attract fruit consumer. This impression is misleading; many small fruits 'go to the dark side' and become dark purple or black when ripe. Intermingled in foliage, these colours, which are produced by anthocyanins, can be fairly inconspicuous and are thus not easily reconciled with a signalling function to attract seed dispersers. In this review I therefore discuss complementary hypotheses on the function and evolution of fruit colouration. First, I focus on the evidence that fruit colours indeed function as signals to attract seed dispersers. I then show that anthocyanins, the most prevalent fruit pigments, are important dietary antioxidants that can be selected by blackcaps ( Sylvia atricapilla) which are important avian seed dispersers of many European plants. Moreover, the consumption of anthocyanins increases the likelihood that blackcaps mount an immune response during immune challenges. As a next step, I review evidence that anthocyanins accumulate in fruit skin in response to abiotic factors, in particular high illumination coupled with low temperature favour the increase of anthocyanins. Finally, I show that anthocyanins can also be selected for by fruit antagonists, consumers that do not disperse seeds. In particular, high contents of anthocyanins strongly reduce fungal growth in fruit tissue. Taken together, there are various selective pressures which likely influence fruit colour evolution. Currently, the relative importance of each of these selective agents is unknown. There is consequently a need to develop a more encompassing framework on fruit colour evolution.

  8. The Dark Side of the Earth

    Science.gov (United States)

    Frankel, Henry

    1986-10-01

    Wood's The Dark Side of the Earth is another addition to the growing list of books on the recent revolution in the earth sciences. Wood rightly points out that any new book on the topic should break new ground. In the preface, he writes of himself and his book that he has benefited from previous accounts by saving himself research time, and that his book, unlike others, “attempts to tell one complete story of the study of the Earth, geologists, geophysicists, dreamers and all” (p. vi). Wood is ambitious, for his work covers much of 19th-century geology as well as the development, reception, rejection, and eventual acceptance of mobilist ideas. Before discussing the work of the German meteorologist and geophysicist Alfred L. Wegener, American glacial geomorphologist Frank Taylor, and several of their predecessors who proposed “mobilist” ideas, he manages to string together brief descriptions of the contributions of (among others) German mineralogist Abraham Gottlob Werner, British geologists James Hutten and John Playfair, British engineer William Smith, British geologist Charles Lyell, American geologists James Hall and James Dwight Dana, British volcanologist William Lowthian Green, American geologist Grove Karl Gilbert, French geologist Elie de Beaumont, British geologist and mathematician Osmond Fisher, American geologist Clarence Dutton, British mathematician and physicist Lord Kelvin, Austrian geologist Eduard Suess, French geologist Marcel Bertrand, and American geologist Thomas Chrowder Chamberlin. Moreover, Wood offers an interesting thesis about the revolution in the earth sciences. He claims that the real revolution was not the replacement of fixist views with the mobilist ones of sea floor spreading and plate tectonics, but rather the replacement of geology with the new discipline of the earth sciences in which geophysics and geochemistry play the central role.

  9. Interpretation of Fuzzy Attribute Subsets in Generalized One-Sided Concept Lattices

    Directory of Open Access Journals (Sweden)

    Peter Butka

    2013-12-01

    Full Text Available In this paper we describe possible interpretation and reduction of fuzzy attributes in GeneralizedOne-sided Concept Lattices (GOSCL. This type of concept lattices represent generalization ofFormal Concept Analysis (FCA suitable for analysis of datatables with different types of attributes. FCA as well as generalized one-sided concept lattices represent conceptual data miningmethods. With growing number of attributes the interpretation of fuzzy subsets may become unclear, hence another interpretation of this fuzzy attribute subsets can be valuable. The originalityof the presented method is based on the usage of one-sided concept lattices derived from submodels of former object-attribute model by grouping attributes with the same truth value structure.This leads to new method for attribute reduction in GOSCL environment.

  10. Metabolic and Endocrine Side Effects of Atypical Antipsychotic Drugs in Children and Adolescents

    Directory of Open Access Journals (Sweden)

    Aysegul Tahiroglu

    2011-03-01

    Full Text Available omorbid psychiatric disorders, frequent hospitalization, multiple outpatient treatment, prior history of hypertension, obesity and lipid dysregulation are associated with higher risk of metabolic syndrome in children. Side effects of antipsychotic drugs and their management have recently become a major subject of research due to enhanced antipsychotic drug usage in child and adolescents. Prevention strategies are usually preferred to secondary or tertiary strategies in the management of metabolic syndrome associated with antipsychotic drugs. Clinicians should present multidisciplinary approach to endocrine and metabolic side effects due to antipsychotic use in pediatric patient groups and avoid multiple drug use in such patients. In this paper, we briefly reviewed metabolic side effects of second generation antipsychotic drugs in child and adolescent population, possible mechanisms of susceptibility to metabolic syndrome and pharmacological and non pharmacological treatment approach to prevention of weight gain.

  11. PERSPECTIVES ON GROUP WORK IN DISTANCE LEARNING

    Directory of Open Access Journals (Sweden)

    Rune Sarromaa HAUSSTÄTTER

    2007-01-01

    Full Text Available Current distance education benefits greatly from educational software that makes group work possible for students who are separated in time and space. However, some students prefer distance education because they can work on their own. This paper explores how students react to expectations on behalf of the course provider to do their assignments in collaborative groups. They are seemingly both positively surprised by the challenges that group work offer, and they are less positive to the downsides of group work. The paper discusses both sides of the experiences and suggests why this might be a paradox to live with.

  12. Trans-polychlorinated azobenzenes (PCABs) - new possibly ''dioxin-like'' environmental pollutants. Multidimensional analysis of the structural feature space of congener set

    Energy Technology Data Exchange (ETDEWEB)

    Falandysz, J.; Wilczynska, A.; Piliszek, S.; Puzyn, T. [Univ. of Gdansk (Poland)

    2004-09-15

    Introduction Azoxybenzene is molecule composed of two benzene ring fused to azoxy group (- N(O)=N-). Trans-PCAOBs consist at 399 congeners, and some of them can be formed as unwanted byproduct in the manufacture of 3,4-dichloroaniline (DCA) and its derivatives, and can be found in herbicides such as Diuron {sup registered}, Linuron {sup registered}, Methazole {sup registered} and Propanil {sup registered}. Degradation of chloroaniline herbicides is also a source of environmental pollution with PCAOBs as well as photolysis and biolysis of DCA. Trans-PCAOBs are planar compounds and can be considered as stereoisomers to highly toxic 2,3,7,8-tetrachlorodibenzo-p-dioxin. They is lack or very limited number of data available regarding to sources, possible mechanism of formation, environmental occurence and fate, analytical chemistry, properties, and effects of trans-PCAOBs. In this work some selected thermodynamic and quantum-mechanical properties of trans- PCAOBs were computed using ab initio methods. Presented property data of trans-PCAOBs can be useful as structural descriptors in further QSAR/QSPR studies of those compounds.

  13. 26 kDa endochitinase from barley seeds: an interaction of the ionizable side chains essential for catalysis

    DEFF Research Database (Denmark)

    Ohnishi, Tsuneo; Juffer, André H; Tamoi, Masahiro;

    2005-01-01

    To explore the structure essential for the catalysis in 26 kDa endochitinase from barley seeds, we calculated theoretical pKa values of the ionizable groups based on the crystal structure, and then the roles of ionizable side chains located near the catalytic residue were examined by site...... mutation. These data clearly demonstrate that the Arg215 side chain interacts with the Glu203 side chain to stabilize the conformation of the catalytic cleft. A similar interaction network was previously found in chitosanase from Streptomyces sp. N174 [Fukamizo et al. (2000) J. Biol. Chem. 275, 25633...

  14. The demand-side management program development process: A utility perspective

    Energy Technology Data Exchange (ETDEWEB)

    Wolfe, A.K. (Oak Ridge National Lab., TN (United States)); Yourstone, N.E. (Yourstone (Evelin), Albuquerque, NM (United States))

    1992-03-01

    This report describes an aspect of DSM that has received little attention, namely, how utilities develop DSM programs. The selection of utilities to study purposely was biased in favor of those with reputations for being experienced DSM program developers so as to optimize the chances to obtain detailed information. The DSM planning process is affected by organizational factors and external influences: (1) the location of the demand-side planning department within the utility; (2) the demand-side planning group's functional responsibilities; (3) upper management participation in the DSM program development process; and (4) the organizational relationship between (or, separation of) supply-side and demand-side planning. Organizational factors reflect utilities' views of DSM programs and thus can affect the adoption of a technology- or customer-oriented approach. Despite repeated claims of the uniqueness of the demand- side planning process and its resistance to standardization, two general approaches to program development were discerned, namely technology- or customer-orientation. Although utilities consider customer related and technological factors in their DSM program development process, utilities can be differentiated by their emphasis on one or the other approach. 25 refs.

  15. Double Sided Si(Ge)/Sapphire/III-Nitride Hybrid Structure

    Science.gov (United States)

    Park, Yeonjoon (Inventor); Choi, Sang Hyouk (Inventor)

    2016-01-01

    One aspect of the present invention is a double sided hybrid crystal structure including a trigonal Sapphire wafer containing a (0001) C-plane and having front and rear sides. The Sapphire wafer is substantially transparent to light in the visible and infrared spectra, and also provides insulation with respect to electromagnetic radio frequency noise. A layer of crystalline Si material having a cubic diamond structure aligned with the cubic direction on the (0001) C-plane and strained as rhombohedron to thereby enable continuous integration of a selected (SiGe) device onto the rear side of the Sapphire wafer. The double sided hybrid crystal structure further includes an integrated III-Nitride crystalline layer on the front side of the Sapphire wafer that enables continuous integration of a selected III-Nitride device on the front side of the Sapphire wafer.

  16. Integrated Groups and Smooth Distribution Groups

    Institute of Scientific and Technical Information of China (English)

    Pedro J. MIANA

    2007-01-01

    In this paper, we prove directly that α-times integrated groups define algebra homo-morphisms. We also give a theorem of equivalence between smooth distribution groups and α-times integrated groups.

  17. Predictors of Side Branch Compromise and related early complications after percutaneous coronary intervention

    Directory of Open Access Journals (Sweden)

    Nozari Y

    2007-07-01

    Full Text Available Background: Percutaneous Coronary Intervention (PCI for bifurcated lesions is associated with a low rate of success and high rate of complications compared to such treatment of lesions of most other morphologies. Symptoms occurring at the time of procedure caused by PCI may require additional angiography with or without stenting through stent struts, which subsequently increases risks of restenosis and stent thrombosis. The purpose of this study was to evaluate the incidence of major side branch (>1mm complications during PCI and their clinical, angiographic, and interventional predictors. Methods: Of 104 consecutive patients, we evaluated 50 lesions with ostial stenosis (group 1 and 54 lesions without ostial stenosis (group 2 as a control group. Age, sex, major coronary artery disease risk factors, and left ventricular ejection fraction (LVEF, were compared between groups. Morphology, location, type of lesion, length of lesion, main and side branch diameters, interventional approach, and clinical and interventional outcomes were the main variables studied during this trial. Results: Side Branch Compromise (SBC occurred in 41 (39.4% of the total number of cases: 52% in group 1 and 27.8% in group 2 (p=0.01. More than 80% of SBC occurred in main branches with stenosis (p=0.02. SBC did not correlate with clinical characteristics, bifurcation location, LVEF, or stent number. Chest pain was reported in 18% of the cases during or after PCI. Three non Q wave myocardial infarctions (MI occurred after SBC, each with >2 mm branch diameters (p=0.02. SBC was not associated with adverse clinical outcomes. Conclusion: The risk of MI after losing the side branch of a bifurcation lesion is not usually as high as it is after losing the main branch. Furthermore, it may not be a serious problem as one of the problems of the bifurcation lesion is the high rate of post procedural non Q wave MI associated with SBC. These findings demonstrate that side branch ostial

  18. Transport properties of a random binary side-coupled chain

    Institute of Scientific and Technical Information of China (English)

    Hu Dong-Sheng; Lu Xiu-Juan; Zhang Yong-Mei; Zhu Chen-Ping

    2009-01-01

    We investigate the transport properties of a random binary side-coupled chain by using the transfer-matrix technique. It is found that there are resonant states in the systems with short-range correlations between the host chain atoms and the side-coupled atoms. The analytic expressions for the extended states are also presented in the systems with the side couplings between like atoms and between unlike atoms.

  19. On Cascade Source Coding with A Side Information "Vending Machine"

    OpenAIRE

    Ahmadi, Behzad; Simeone, Osvaldo; Choudhuri, Chiranjib; Mitra, Urbashi

    2012-01-01

    The model of a side information "vending machine" accounts for scenarios in which acquiring side information is costly and thus should be done efficiently. In this paper, the three-node cascade source coding problem is studied under the assumption that a side information vending machine is available either at the intermediate or at the end node. In both cases, a single-letter characterization of the available trade-offs among the rate, the distortions in the reconstructions at the intermediat...

  20. Which finite simple groups are unit groups?

    DEFF Research Database (Denmark)

    Davis, Christopher James; Occhipinti, Tommy

    2014-01-01

    We prove that if G is a finite simple group which is the unit group of a ring, then G is isomorphic to either (a) a cyclic group of order 2; (b) a cyclic group of prime order 2^k −1 for some k; or (c) a projective special linear group PSLn(F2) for some n ≥ 3. Moreover, these groups do all occur as...... unit groups. We deduce this classification from a more general result, which holds for groups G with no non-trivial normal 2-subgroup....

  1. Wake structures of two side by side spheres in a tripped boundary layer flow

    Directory of Open Access Journals (Sweden)

    Canli Eyüb

    2014-03-01

    Full Text Available Two independent spheres were placed in a side by side arrangement and flow structure in the wake region of the spheres was investigated with a Particle Image Velocimetry (PIV system when the spheres were in a boundary layer over a flat plate as a special case. Reynolds number was 5000 based on the sphere diameter which was 42.5 mm. Boundary layer was tripped 8mm away from the leading edge of the flat plate with a 5 mm trip wire. The thickness of the hydrodynamically developed boundary layer was determined as 63mm which was larger than the sphere diameter of D=42.5mm. Wake region of the spheres was examined from point of flow physics for the different sphere locations in the ranges of 0≤G/D ≤1.5 and 0≤S/D ≤1.5 where G and S were the distance between the spheres and the distance between the bottom point of the spheres and the flat plate surface, respectively. Depending on the different sphere locations, instantaneous and time averaged vorticity data, scalar values of time-averaged velocity components and their root mean square (rms values and time averaged vorticity data are presented in the study for the evaluation of wake region of the spheres. It is demonstrated that the gap between the two spheres and the interaction between the gap and the boundary layer greatly affects flow pattern, especially when spheres are located near to the flat plate surface, i.e. S/D=0.1 for 0≤G/D ≤1.5. Different distances between the spheres resulted in various flow patterns as the spheres were approached to the flat plate. The distance S/D=0.1 for all gap values has the strongest effect on the wake structures. Beyond G/D=1.0, the sphere wakes tend to be similar to single sphere case. The instantaneous vorticity fields of the side by side arrangements comprised wavy structures in higher level comparing to an individual sphere case. The gap flow intensifies the occurrence of small scale eddies in the wake region. The submersion rate of the spheres

  2. The odd side of torsion geometry

    OpenAIRE

    Conti, D; Madsen, T

    2012-01-01

    We introduce and study a notion of `Sasaki with torsion structure' (ST) as an odd-dimensional analogue of Kähler with torsion geometry (KT). These are normal almost contact metric manifolds that admit a unique compatible connection with 3-form torsion. Any odd-dimensional compact Lie group is shown to admit such a structure; in this case the structure is left-invariant and has closed torsion form.We illustrate the relation between ST structures and other generalizations of Sasaki geometry, an...

  3. Review: Tales from Both Sides of the Brain.

    Science.gov (United States)

    Landis, Theodor

    2015-01-01

    Our brain has two hemispheres that specialize in different jobs-the right side processes spatial and temporal information, and the left side controls speech and language. How these two sides come together to create one mind is explained by pioneering neuroscientist Michael Gazzaniga in his new book, Tales from Both Sides of the Brain : A Life in Neuroscience (Ecco/Harper Collins, 2015). Gazzaniga is director of the SAGE Center for the Study of the Mind at the University of California, Santa Barbara, and a Dana Alliance member. PMID:27408671

  4. Measuring side effects after radiotherapy for pharynx cancer

    DEFF Research Database (Denmark)

    Jensen, Kenneth

    2007-01-01

    Data on side effects after radiotherapy is needed to establish the benefits and drawbacks of new treatments, but side effects are not quantified as easily as survival or local control. Side effects may be quantified using physical measures. Unfortunately, only few endpoints exist where a physical...... side effects. Using pharynx cancer as an example, the purpose of this article is to summarize the possibilities and limitations of different methods for measurement of radiotherapy-induced side effects. Udgivelsesdato: 2007-Sep-17......Data on side effects after radiotherapy is needed to establish the benefits and drawbacks of new treatments, but side effects are not quantified as easily as survival or local control. Side effects may be quantified using physical measures. Unfortunately, only few endpoints exist where a physical...... measure is obtainable, and the case of a patient-relevant measure is even rarer. Radiotherapy is often followed by complex symptoms not easily quantifiable by the observer. Quantitative patient reported side effects can be retrieved using validated questionnaires, but this kind of data is often difficult...

  5. Simultaneous in vivo truncation of pectic side chains

    DEFF Research Database (Denmark)

    Øbro, Jens; Borkhardt, Bernhard; Harholt, Jesper;

    2009-01-01

    . These modifications often prevent gelation, which has been a major functional requirement of commercial pectins until recently. We have previously shown that modification of pectin is possible through heterologous expression of pectin degrading enzymes in planta. To test the effect of simultaneous...... modification of the two main neutral pectic side chains in pectic rhamnogalacturonan I (RGI), we constitutively expressed two different enzymes in Arabidopsis thaliana that would either modify the galactan or the arabinan side chains, or both side chains simultaneously. Our analysis showed that the...... simultaneous truncation of arabinan and galactan side chains is achievable and does not severely affect the growth of Arabidopsis thaliana....

  6. On Cascade Source Coding with A Side Information "Vending Machine"

    CERN Document Server

    Ahmadi, Behzad; Choudhuri, Chiranjib; Mitra, Urbashi

    2012-01-01

    The model of a side information "vending machine" accounts for scenarios in which acquiring side information is costly and thus should be done efficiently. In this paper, the three-node cascade source coding problem is studied under the assumption that a side information vending machine is available either at the intermediate or at the end node. In both cases, a single-letter characterization of the available trade-offs among the rate, the distortions in the reconstructions at the intermediate and at the end node, and the cost in acquiring the side information are derived under given conditions.

  7. Source Coding with a Side Information "Vending Machine"

    OpenAIRE

    Weissman, Tsachy; Permuter, Haim H.

    2009-01-01

    We study source coding in the presence of side information, when the system can take actions that affect the availability, quality, or nature of the side information. We begin by extending the Wyner-Ziv problem of source coding with decoder side information to the case where the decoder is allowed to choose actions affecting the side information. We then consider the setting where actions are taken by the encoder, based on its observation of the source. Actions may have costs that are commens...

  8. Dynamic hip screw with locking side plate: a viable treatment option for intertrochanteric fracture

    Institute of Scientific and Technical Information of China (English)

    Nilesh Barwar; Sanjay Meena; Shashi Kant Aggarwal; Prashant Garhwal

    2014-01-01

    Objective:Dynamic hip screw (DHS) is recommended for the fixation of stable intertrochanteric fractures.Its postoperative cut-out rate ranges from 1% to 6%.In osteoporotic bone,normal screws in DHS blade provide less anchorage compared to locking screws.This study aims to compare DHS with locking side plate and conventional side plate.Methods:Fifty consecutive patients with intertrochanteric fractures were randomly allocated for fixation with a standard DHS (group A) and locking DHS (Combi plate,group B).We compared the clinical and radiological outcomes for the conventional DHS and locking DHS in intertrochanteric fractures.Functional outcome was evaluated using the Parker mobility score.Results:Coxa valga was found more frequently in group A than in group B (12% vs.0%,P=0.42).Coxa vara showed the same trend (12% vs.8%,P=0.81).Rate of restoration of postoperative neck-shaft angle within 20° of sound side was higher in group B (8% cases) than in group A (4% cases,P=0.98).The rate of anteversion angle restoration within 10° of sound side was also higher in group B (100% vs.88%,P=0.85).The average lag screw slippage in group A and group B was 3.2 mm and 4.2 mm,the average fracture union duration was 17.1 weeks and 16.4 weeks,and the mean Parker score was 5.6 and 5.8 respectively.Screw cut-out was seen in one patient in group A.No cut-out was seen in any of the patient in group B.No patient developed deep infection,avascular necrosis,deep vein thrombosis or any other significant complications.Conclusion:The present study demonstrated that treating intertrochanteric fracture with a locking DHS allows sound bone healing and is not associated with any major complications.Although this report is promising,it should be interpreted with caution because only a prospective study with a large sample size would allow definitive conclusion.

  9. Effects of uniform magnetic field on the interaction of side-by-side rising bubbles in a viscous liquid

    Energy Technology Data Exchange (ETDEWEB)

    Hadidi, Amin; Jalali-Vahid, Davood [Faculty of Mechanical Engineering, Sahand University of Technology, Tabriz (Iran, Islamic Republic of)

    2016-03-15

    Effects of uniform magnetic fields on the interaction and coalescence of side-by-side rising bubbles of dielectric fluids were not studied; so in the present research, effects of different strengths of uniform magnetic field on the interaction of two bubbles rising side by side in a viscous and initially stagnant liquid are studied, numerically. For numerical modeling of the problem, a full computer code was developed to solve the governing equations which are continuity, Navier-Stokes, magnetic field and interface capturing equations which are level set and re-initialization equations. The finite volume method is used for the discretization of the hydrodynamic equations where the finite difference method is used to discretization of the magnetic field equations. The results are compared with available numerical and experimental results which show a good agreement. It is found that the uniform magnetic field can be used for contactless control of side-by-side coalescence of bubbles.

  10. Side-to-side growth discrepancies in children with hemiplegic cerebral palsy: association with function, activity and social participation

    Directory of Open Access Journals (Sweden)

    Marise Bueno Zonta

    2014-05-01

    Full Text Available Objective: Evaluate side-to-side discrepancies in children with hemiplegic cerebral palsy (HCP, and investigate associations of these discrepancies with patients’ age at initiation of physical therapy, motor and cognitive function, and degree of activities and social participation. Method: We obtained eight side-to-side measurements from 24 HCP children with mean age 49.3±5.2 months. Results: Early initiation of physical therapy was associated with lower discrepancy in hand length (p=0.037. Lower foot length discrepancy was associated with lower requirement for caregiver assistance in activities related to mobility. Increased side-to-side discrepancy was associated with reduced wrist extension and increased spasticity. Discrepancy played a larger role in children with hemineglect and in those with right involvement. Conclusion: Increased discrepancy in HCP children was associated with reduced degree of activity/social participation. These results suggest an association between functional use of the extremities and limb growth.

  11. FLOW PAST TWO ROTATING CIRCULAR CYLINDERS IN A SIDE-BY-SIDE ARRANGEMENT

    Institute of Scientific and Technical Information of China (English)

    GUO Xiao-hui; LIN Jian-zhong; TU Cheng-xu; WANG Hao-li

    2009-01-01

    Measurements were performed using Particle Image Velocimetry (PIV) to analyze the modification of flow by the combined effects of the rotation and the Reynolds number on the flow past two rotating circular cylinders in a side-by-side-arrangement at a range of , (α is the rotational speed) at one gap spacing of (T and d are the distance between the centers of two cylinders and the cylinder diameter, respectively). A new Immersed-Lattice Boltzmann Method (ILBM) scheme was used to study the effect of the gap spacing on the flow. The results show that the vortex shedding is suppressed as rotational speed increases. The flow reaches a steady state when the vortex shedding for both cylinders is completely suppressed at critical rotational speed. As the rotational speed further increases, the separation phenomenon in the boundary layers disappears at the attachment rotational speed. The critical rotational speed and attachment rotational speed become small as Reynolds number increases. The absolute rotational speed of cylinders should be large at same critical rotational speed and attachment rotational speed in the case of large Reynolds number. The gap spacing has an important role in changing the pattern of vortex shedding. It is very different in the mechanism of vortex shedding suppression for the flows around two rotating cylinders and single rotating cylinder.

  12. A side-by-side evaluation of four platelet-counting instruments.

    Science.gov (United States)

    Dalton, W T; Bollinger, P; Drewinko, B

    1980-08-01

    The performances of four instruments for counting platelets were evaluated in a side-by-side study: the Haema-Count MK-4/HC, an electronic impedance instrument that counts platelets in platelet-rich plasma; the Ultra-Flo 100, and the Coulter Counter Model S-Plus, electronic impedance instruments that count platelets in the presence of intact erythrocytes; and the AutoCounter, an optical instrument that counts platelets in the presence of lysed erythrocytes. The Ultra-Flo 100 and the S-Plus showed the best within-run precision, and all four instruments were considerably more precise than manual platelet counting, especially at low levels of platelet count. The four instruments were all linear in the ranges tested (5 to 650 x 10(9)/or greater), and sample carry-over was less than 0.7% for each. A noteworthy finding was that the erythrocyte concentration of the blood samples affected the displayed platelet count of the S-Plus and, to a lesser extent, that of the AutoCounter, in a predictable way, whereas it did not greatly affect the displayed count of the Ultra-Flo 100. In addition to differences in quality of performances, the four instruments differed considerably in speed and ease of operation and in cost. PMID:7405890

  13. Numerical Study on Interaction Between Two Bubbles Rising Side by Side in CMC Solution

    Institute of Scientific and Technical Information of China (English)

    FAN Wenyuan; YIN Xiaohong

    2013-01-01

    A numerical simulation was performed to investigate the interaction of two bubbles rising side by side in shear-thinning fluid using volume of fluid (VOF) method coupled with continuous surface force (CSF) method.By considering rheological characteristics of fluid,this approach was able to accurately capture the deformation of bubble interface,and validated by comparing with the experimental results.The rising of bubble pairs with different configurations,including horizontal alignment and oblique alignment,was simulated by the method.The influences of the bubble initial distance and the bubble alignment were studied by analyzing the bubble deformation,rising paths and flow fields surrounding bubbles.The results indicate that within certain initial bubble spacing of S* =3.3(S* =SI/D,SI initial distance between bubbles,and D bubble diameter),the dynamic interaction between two bubbles aligned horizontally shows repulsive effect that decreases with the increase of initial bubble spacing,but weakens to certain degree by the shear-thinning properties of fluid.However,the interaction between two bubbles aligned obliquely presents a repulsive effect for the small angle involved but an attractive impact for the large one,which is yet strengthened by the rheological characteristics of fluid.

  14. Modality-specific communication enabling gait synchronization during over-ground side-by-side walking.

    Science.gov (United States)

    Zivotofsky, Ari Z; Gruendlinger, Leor; Hausdorff, Jeffrey M

    2012-10-01

    An attentive observer will notice that unintentional synchronization of gait between two walkers on the street seems to occur frequently. Nonetheless, the rate of occurrence and motor-sensory mechanisms underlying this phase-locking of gait have only recently begun to be investigated. Previous studies have either been qualitative or carried out under non-natural conditions, e.g., treadmill walking. The present study quantitatively examined the potential sensory mechanisms that contribute to the gait synchronization that occurs when two people walk side by side along a straight, over-ground, pathway. Fourteen pairs of subjects walked 70 m under five conditions that manipulated the available sensory feedback. The modalities studied were visual, auditory, and tactile. Movement was quantified using a trunk-mounted tri-axial accelerometer. A gait synchronization index (GSI) was calculated to quantify the phase synchronization of the gait rhythms. Overall, 36% of the walks exhibited synchrony. Tactile and auditory feedback showed the greatest ability to synchronize, while visual feedback was the least effective. The results show that gait synchronization during natural walking is common, quantifiable, and has modality-specific properties.

  15. Side-by-side ANFIS as a useful tool for estimating correlated thermophysical properties

    Science.gov (United States)

    Grieu, Stéphane; Faugeroux, Olivier; Traoré, Adama; Claudet, Bernard; Bodnar, Jean-Luc

    2015-12-01

    In the present paper, an artificial intelligence-based approach dealing with the estimation of correlated thermophysical properties is designed and evaluated. This new and "intelligent" approach makes use of photothermal responses obtained when homogeneous materials are subjected to a light flux. Commonly, gradient-based algorithms are used as parameter estimation techniques. Unfortunately, such algorithms show instabilities leading to non-convergence in case of correlated properties to be estimated from a rebuilt impulse response. So, the main objective of the present work was to simultaneously estimate both the thermal diffusivity and conductivity of homogeneous materials, from front-face or rear-face photothermal responses to pseudo random binary signals. To this end, we used side-by-side neuro-fuzzy systems (adaptive network-based fuzzy inference systems) trained with a hybrid algorithm. We focused on the impact on generalization of both the examples used during training and the fuzzification process. In addition, computation time was a key point to consider. That is why the developed algorithm is computationally tractable and allows both the thermal diffusivity and conductivity of homogeneous materials to be simultaneously estimated with very good accuracy (the generalization error ranges between 4.6% and 6.2%).

  16. Material Selection for Hawsers for a Side-by-side Offloading System

    Institute of Scientific and Technical Information of China (English)

    Jiayu Qian; Liping Sun; Linfeng Song

    2014-01-01

    In order to provide a theoretical guide for choosing the material for the hawsers for the FPSO side-by-side offloading system, which is moored by the yoke system, the 3D potential flow theory and full coupled time-domain analysis are presented to study the dynamic response of the offloading system. The MingZhu FPSO offloading system in the field BZ25-1 is simulated here;and four different characteristic fiber ropes are used as the material for the hawsers. To acquire an accurate hawser line tension, the polynomial fitting method is used to calculate the nonlinear stiffness of the hawsers. By comparing the hawser lines’ tension and the relative motion between the FPSO and the shuttle tanker, a suitable material for the hawser lines is chosen and discussed in this paper. The results indicate that the nonlinear stiffness characteristic of the fiber rope has a small effect on the relative motion of the vessels, but the hawser lines’ tension is greatly influenced by the different characteristics of the fiber ropes. The hawser lines’ tension with nonlinear stiffness is in accordance with the one with the upper and lower bound linear stiffness, which proves this method of fitting the fiber ropes’ nonlinear stiffness is reasonable and reliable.

  17. Propulsive performance of unsteady tandem hydrofoils in a side-by-side configuration

    Science.gov (United States)

    Dewey, Peter A.; Quinn, Daniel B.; Boschitsch, Birgitt M.; Smits, Alexander J.

    2014-04-01

    Experimental and analytical results are presented on two identical bio-inspired hydrofoils oscillating in a side-by-side configuration. The time-averaged thrust production and power input to the fluid are found to depend on both the oscillation phase differential and the transverse spacing between the foils. For in-phase oscillations, the foils exhibit an enhanced propulsive efficiency at the cost of a reduction in thrust. For out-of-phase oscillations, the foils exhibit enhanced thrust with no observable change in the propulsive efficiency. For oscillations at intermediate phase differentials, one of the foils experiences a thrust and efficiency enhancement while the other experiences a reduction in thrust and efficiency. Flow visualizations reveal how the wake interactions lead to the variations in propulsive performance. Vortices shed into the wake from the tandem foils form vortex pairs rather than vortex streets. For in-phase oscillation, the vortex pairs induce a momentum jet that angles towards the centerplane between the foils, while out-of-phase oscillations produce vortex pairs that angle away from the centerplane between the foils.

  18. The dark side of Taiwan's globalization success story.

    Science.gov (United States)

    Sass, R

    2000-01-01

    Government regulators and researchers in Taiwan (Republic of China) express optimism about their country's economic success in its transition from a traditional society to a first world, industrialized nation. But this economic success, as measured by the standards and ideology of globalization, also has a dark side for many ordinary workers, especially Taiwan's 300,000 foreign workers. The promise of growth and future prosperity is conditional upon global economic practices and an adherence to a science-technology ideological perspective that shapes political content. Multiple centers of opposition and critical thinking have no public presence in Taiwan; nor do organizational defiance and resistance by trade unions. Instead, individuals and small human rights groups seek to reveal areas of human degradation and suffering in a response to poverty and the American dream. Meanwhile, the dominant ideological perspective as articulated by globalism seeps into and directs all public policy on the work environment so that it is coherent with the neoliberal political agenda of multinational corporations. This direction is being questioned by students of the work environment and by labor activists in North America, who report the deterioration of working conditions and worsening of government regulatory instruments for protecting workers from physical, mental, and social risk and harm in the workplace. PMID:11127019

  19. Workplace violence: the dark side of organisational life.

    Science.gov (United States)

    Speedy, Sandra

    2006-05-01

    This paper draws on a diverse range of research literature addressing workplace violence, which constitutes one component of the dark side of organisational life. This selective review of the literature has been drawn from the disciplines of nursing, management, psychology and organisational culture. The paper focuses bullying and mobbing in the workplace, addressing its types, causes, the characteristics of bullies and targets and the generalised impact of bullying and mobbing. It also examines whether there are gender issues pertinent to the health care sector. Consideration will also be given to the impact on the individual, group and organization, given the apparent epidemic proportions workplace violence has reached. Ultimately, the question will arise: how can the workplace violence be abolished, specifically within the health care sector, given that we live in a global environment characterised by international bullying (Crawford 1999)? This is a challenge because workplace violence is perpetuated within organisations, due either to cultures of acceptance, or fear of retribution should it be acknowledged and acted upon (or both). PMID:16696606

  20. Group Composition, Group Interaction and Achievement in Cooperative Small Groups.

    Science.gov (United States)

    Webb, Noreen M.

    This study investigated interaction and achievement in cooperative small groups in four junior high school mathematics classrooms. Ninety-six students learned a one-week unit on consumer mathematics in mixed-ability or uniform-ability groups. Students in mixed-ability groups scored higher on a problem-solving test than students in uniform-ability…