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Sample records for addition-fragmentation chain transfer

  1. Reversible addition-fragmentation chain transfer polymerization in microemulsion.

    Science.gov (United States)

    O'Donnell, Jennifer M

    2012-04-21

    This tutorial review first details the uncontrolled microemulsion polymerization mechanism, and the RAFT polymerization mechanism to provide the necessary background for examining the RAFT microemulsion polymerization mechanism. The effect of the chain transfer agent per micelle ratio and the chain transfer agent aqueous solubility on the RAFT microemulsion polymerization kinetics, polymer molecular weight and polydispersity, and polymer nanoparticle size are discussed with a focus on oil-in-water microemulsions. Modeling of RAFT microemulsion polymerization kinetics and the resulting final polymer molecular weight are presented to assist with the analysis of observed experimental trends. Lastly, the current significance of RAFT microemulsion polymerization and the future directions are discussed. PMID:22246214

  2. The reversible addition-fragmentation chain transfer (RAFT) miniemulsion polymerization of vinyl acetate mediated by xanthate

    Institute of Scientific and Technical Information of China (English)

    Bo Jiang; Qing Hua Zhang; Xiao Li Zhan; Feng Qiu Chen

    2009-01-01

    The reversible addition-fragmentation chain transfer (RAFT) miniemulsion polymerization of vinyl acetate (VAt) mediated by methyl (methoxycarbonothioyl) sulfanyl acetate (MMSA) was carried out. The results showed that polymerizations initiated by AIBN and KPS proceeded in a controlled way. The RAFT miniemulsion polymerization of VAc initiated by KPS showed the shorter inhibition period, higher propagation rate coefficient and final conversion than those in experiment initiated by AIBN. When the monomer conversion reached 25%, the polydispersity index (PDI) of polymer became broad, which was related to chain transfer reaction in RAFT miniemulsion of VAc.

  3. Evaluation of the clenbuterol imprinted monolithic column prepared by reversible addition-fragmentation chain transfer polymerization

    Institute of Scientific and Technical Information of China (English)

    Mamat Turson; Xiao Lei Zhuang; Hui Na Liu; Ping Jiang; Xiang Chao Dong

    2009-01-01

    To make more homogenous organic monolithic structure,reversible addition-fragmentation chain transfer(RAFT)process was employed in the synthesis of the clenbuterol imprinted polymer.In the synthesis,the influence of synthetic conditions on the polymer structure and separation efficiency was studied.The result demonstrated that the imprinted columns prepared with RAFT process have higher column efficiency and selectivity than the columns prepared with conventional polymerization in the present study,which may result from the higher surface area,smaller pore size and the narrower globule size distribution in their structures.The result indicated that RAFT polymerization provided better conditions for the clenbuterol imprinted monolithic polymer preparation.

  4. Polymer-grafted lignin surfactants prepared via reversible addition-fragmentation chain-transfer polymerization.

    Science.gov (United States)

    Gupta, Chetali; Washburn, Newell R

    2014-08-12

    Kraft lignin grafted with hydrophilic polymers has been prepared using reversible addition-fragmentation chain-transfer (RAFT) polymerization and investigated for use as a surfactant. In this preliminary study, polyacrylamide and poly(acrylic acid) were grafted from a lignin RAFT macroinitiator at average initiator site densities estimated to be 2 per particle and 17 per particle. The target degrees of polymerization were 50 and 100, but analysis of cleaved polyacrylamide was consistent with a higher average molecular weight, suggesting not all sites were able to participate in the polymerization. All materials were readily soluble in water, and dynamic light scattering data indicate polymer-grafted lignin coexisted in isolated and aggregated forms in aqueous media. The characteristic size was 15-20 nm at low concentrations, and aggregation appeared to be a stronger function of degree of polymerization than graft density. These species were surface active, reducing the surface tension to as low as 60 dyn/cm at 1 mg/mL, and a greater decrease was observed than for polymer-grafted silica nanoparticles, suggesting that the lignin core was also surface active. While these lignin surfactants were soluble in water, they were not soluble in hexanes. Thus, it was unexpected that water-in-oil emulsions formed in all surfactant compositions and solvent ratios tested, with average droplet sizes of 10-20 μm. However, although polymer-grafted lignin has structural features similar to nanoparticles used in Pickering emulsions, its interfacial behavior was qualitatively different. While at air-water interfaces, the hydrophilic grafts promote effective reductions in surface tension, we hypothesize that the low grafting density in these lignin surfactants favors partitioning into the hexanes side of the oil-water interface because collapsed conformations of the polymer grafts improve interfacial coverage and reduce water-hexanes interactions. We propose that polymer-grafted lignin

  5. Functionalization of vertically aligned carbon nanotubes with polystyrene via surface initiated reversible addition fragmentation chain transfer polymerization

    Energy Technology Data Exchange (ETDEWEB)

    Macdonald, Thomas; Gibson, Christopher T.; Constantopoulos, Kristina; Shapter, Joseph G. [Flinders Centre for Nanoscale Science and Technology, School of Chemical and Physical Sciences, Flinders University, GPO Box 2100, Adelaide, SA, 5001 (Australia); Ellis, Amanda V., E-mail: amanda.ellis@flinders.edu.au [Flinders Centre for Nanoscale Science and Technology, School of Chemical and Physical Sciences, Flinders University, GPO Box 2100, Adelaide, SA, 5001 (Australia)

    2012-01-15

    Here we demonstrate the covalent attachment of vertically aligned (VA) acid treated single-walled carbon nanotubes (SWCNTs) onto a silicon substrate via dicyclohexylcarbodiimide (DCC) coupling chemistry. Subsequently, the pendant carboxyl moieties on the sidewalls of the VA-SWCNTs were derivatized to acyl chlorides, and then finally to bis(dithioester) moieties using a magnesium chloride dithiobenzoate salt. The bis(dithioester) moieties were then successfully shown to act as a chain transfer agent (CTA) in the reversible addition fragmentation chain transfer (RAFT) polymerization of styrene in a surface initiated 'grafting-from' process from the VA-SWCNT surface. Atomic force microscopy (AFM) verified vertical alignment of the SWCNTs and the maintenance thereof throughout the synthesis process. Finally, Raman scattering spectroscopy and AFM confirmed polystyrene functionalization.

  6. Early career: Templating of liquid crystal microstructures by reversible addition-fragmentation chain transfer polymerization

    Energy Technology Data Exchange (ETDEWEB)

    Heinen, Jennifer M. (O' Donnell) [Iowa State Univ., Ames, IA (United States)

    2014-12-31

    This research has shown that the microstructure of self-assembled copolymers can be decoupled from the polymer chemistry. The simplest polymer architecture, linear block copolymers, is valuable for a broad range of applications, including adhesives and coatings, medical devices, electronics and energy storage, because these block copolymers reproducibly self-assemble into microphase separated nanoscale domains. Unfortunately, the self-assembled microstructure is tuned by polymer composition, thus limiting the potential to simultaneously optimize chemical, mechanical, and transport properties for desired applications. To this end, much work was been put into manipulating block copolymer self-assembly independently of polymer composition. These efforts have included the use of additives or solvents to alter polymer chain conformation, the addition of a third monomer to produce ABC triblock terpolymers, architectures with mixed blocks, such as tapered/gradient polymers, and the synthesis of other nonlinear molecular architectures. This work has shown that the microstructures formed by linear ABC terpolymers can be altered by controlling the architecture of the polymer molecules at a constant monomer composition, so that the microstructure is tuned independently from the chemical properties.

  7. Study on the performance of polycarboxylate-based superplasticizers synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization

    Science.gov (United States)

    Yu, Binbin; Zeng, Zhong; Ren, Qinyu; Chen, Yang; Liang, Mei; Zou, Huawei

    2016-09-01

    A series of block type polycarboxylate-based superplasticizers (PCs) with different molecular architectures were synthesized with macromonomer butenyl alkylene polyoxyethylene-polyoxypropylene ether (BAPP) and acrylic acid (AA) by reversible addition-fragmentation chain transfer (RAFT) polymerization. Fourier-Transformed Infrared (FTIR) Spectroscopy and dynamic light scattering (DLS) were applied to investigate the PCs' molecular structure. The dispersion capacity of the PCs in cement were also measured, and the results showed that the polycarboxylic dispersing agents prepared by this method were suitable for portlant cement. It was found that the PCs could affect the hydration process, which was performed through retarding the generation of ettringite in the hydrated product. Our studies with X-ray diffraction (XRD), scanning electron microscopy (SEM) and compressive strength measurement of hydrated production were all supporting this conclusion.

  8. Scale-up of the Reversible Addition-Fragmentation Chain Transfer (RAFT Polymerization Using Continuous Flow Processing

    Directory of Open Access Journals (Sweden)

    Nenad Micic

    2014-01-01

    Full Text Available A controlled radical polymerization process using the Reversible Addition-Fragmentation Chain Transfer (RAFT approach was scaled up by a factor of 100 from a small laboratory scale of 5 mL to a preparative scale of 500 mL, using batch and continuous flow processing. The batch polymerizations were carried out in a series of different glass vessels, using either magnetic or overhead stirring, and different modes of heating: Microwave irradiation or conductive heating in an oil bath. The continuous process was conducted in a prototype tubular flow reactor, consisting of 6 mm ID stainless steel tubing, fitted with static mixers. Both reactor types were tested for polymerizations of the acid functional monomers acrylic acid and 2-acrylamido-2-methylpropane-1-sulfonic acid in water at 80 °C with reaction times of 30 to 40 min. By monitoring the temperature during the exothermic polymerization process, it was observed that the type and size of reactor had a significant influence on the temperature profile of the reaction.

  9. Thermally conductive, electrically insulating and melt-processable polystyrene/boron nitride nanocomposites prepared by in situ reversible addition fragmentation chain transfer polymerization.

    Science.gov (United States)

    Huang, Xingyi; Wang, Shen; Zhu, Ming; Yang, Ke; Jiang, Pingkai; Bando, Yoshio; Golberg, Dmitri; Zhi, Chunyi

    2015-01-01

    Thermally conductive and electrically insulating polymer/boron nitride (BN) nanocomposites are highly attractive for various applications in many thermal management fields. However, so far most of the preparation methods for polymer/BN nanocomposites have usually caused difficulties in the material post processing. Here, an in situ grafting approach is designed to fabricate thermally conductive, electrically insulating and post-melt processable polystyrene (PS)/BN nanosphere (BNNS) nanocomposites by initiating styrene (St) on the surface functionalized BNNSs via reversible addition fragmentation chain transfer polymerization. The nanocomposites exhibit significantly enhanced thermal conductivity. For example, at a St/BN feeding ratio of 5:1, an enhancement ratio of 1375% is achieved in comparison with pure PS. Moreover, the dielectric properties of the nanocomposites show a desirable weak dependence on frequency, and the dielectric loss tangent of the nanocomposites remains at a very low level. More importantly, the nanocomposites can be subjected to multiple melt processing to form different shapes. Our method can become a universal approach to prepare thermally conductive, electrically insulating and melt-processable polymer nanocomposites with diverse monomers and nanofillers. PMID:25493655

  10. Thermally conductive, electrically insulating and melt-processable polystyrene/boron nitride nanocomposites prepared by in situ reversible addition fragmentation chain transfer polymerization

    Science.gov (United States)

    Huang, Xingyi; Wang, Shen; Zhu, Ming; Yang, Ke; Jiang, Pingkai; Bando, Yoshio; Golberg, Dmitri; Zhi, Chunyi

    2015-01-01

    Thermally conductive and electrically insulating polymer/boron nitride (BN) nanocomposites are highly attractive for various applications in many thermal management fields. However, so far most of the preparation methods for polymer/BN nanocomposites have usually caused difficulties in the material post processing. Here, an in situ grafting approach is designed to fabricate thermally conductive, electrically insulating and post-melt processable polystyrene (PS)/BN nanosphere (BNNS) nanocomposites by initiating styrene (St) on the surface functionalized BNNSs via reversible addition fragmentation chain transfer polymerization. The nanocomposites exhibit significantly enhanced thermal conductivity. For example, at a St/BN feeding ratio of 5:1, an enhancement ratio of 1375% is achieved in comparison with pure PS. Moreover, the dielectric properties of the nanocomposites show a desirable weak dependence on frequency, and the dielectric loss tangent of the nanocomposites remains at a very low level. More importantly, the nanocomposites can be subjected to multiple melt processing to form different shapes. Our method can become a universal approach to prepare thermally conductive, electrically insulating and melt-processable polymer nanocomposites with diverse monomers and nanofillers.

  11. Thermally conductive, electrically insulating and melt-processable polystyrene/boron nitride nanocomposites prepared by in situ reversible addition fragmentation chain transfer polymerization

    International Nuclear Information System (INIS)

    Thermally conductive and electrically insulating polymer/boron nitride (BN) nanocomposites are highly attractive for various applications in many thermal management fields. However, so far most of the preparation methods for polymer/BN nanocomposites have usually caused difficulties in the material post processing. Here, an in situ grafting approach is designed to fabricate thermally conductive, electrically insulating and post-melt processable polystyrene (PS)/BN nanosphere (BNNS) nanocomposites by initiating styrene (St) on the surface functionalized BNNSs via reversible addition fragmentation chain transfer polymerization. The nanocomposites exhibit significantly enhanced thermal conductivity. For example, at a St/BN feeding ratio of 5:1, an enhancement ratio of 1375% is achieved in comparison with pure PS. Moreover, the dielectric properties of the nanocomposites show a desirable weak dependence on frequency, and the dielectric loss tangent of the nanocomposites remains at a very low level. More importantly, the nanocomposites can be subjected to multiple melt processing to form different shapes. Our method can become a universal approach to prepare thermally conductive, electrically insulating and melt-processable polymer nanocomposites with diverse monomers and nanofillers. (paper)

  12. The Effect of Allylic Sulfide-Mediated IrreversibleAddition-Fragment Chain Transfer on the EmulsionPolymerization Kinetics of Styrene

    Directory of Open Access Journals (Sweden)

    Li An

    2015-09-01

    Full Text Available The effect of the irreversible addition-fragment chain transfer agent, butyl(2-phenylallylsulfane (BPAS, on the course of the emulsion polymerization of styrene and on the product molecular weight was investigated. The emulsion polymerizations were performed using various amounts of sodium dodecyl sulfate (SDS as the surfactant and potassium peroxodisulfate (KPS as the initiator. The relationships between the rates of polymerization (\\(R_{p} \\ and the number of particles per volume (\\(N_{c} \\ with respect to the concentrations of KPS, SDS, and BPAS were found to be \\(R_{p} \\propto \\left\\lbrack KPS \\right\\rbrack^{0.29} \\, \\(N_{c} \\propto \\left\\lbrack KPS \\right\\rbrack^{0.26} \\,\\(R_{p} \\propto \\left\\lbrack SDS \\right\\rbrack^{0.68} \\, \\(N_{c} \\propto \\left\\lbrack SDS \\right\\rbrack^{0.72} \\, and \\(R_{p} \\propto \\left\\lbrack BPAS \\right\\rbrack^{- 0.73} \\ . The obtained relationships can be attributed to the exit of the leaving group radicals on BPAS from the polymer particles. The experimental values of the average number of radicals per particle (\\(\\overset{\\_}{n} \\ were strongly dependent on the BPAS concentration and were in good agreement with the theoretical values (\\({\\overset{\\_}{n}}_{theo} \\ from model calculations. The number-average molecular weight (\\(\\overset{\\_}{M_{n}} \\ can be controlled by BPAS over nearly the entire conversion range, which is also in agreement with the mathematical model. In addition, the transfer rate coefficient (\\(k_{tr} \\ of BPAS can be estimated as 326 L/mol/s at 70 \\(^\\circ\\C. Moreover, similar good results were found for the tested redox reactions at 30 \\(^\\circ\\C.

  13. Surface molecular imprinting onto fluorescein-coated magnetic nanoparticlesvia reversible addition fragmentation chain transfer polymerization: A facile three-in-one system for recognition and separation of endocrine disrupting chemicals

    Science.gov (United States)

    Li, Ying; Dong, Cunku; Chu, Jia; Qi, Jingyao; Li, Xin

    2011-01-01

    In this study, we present a general protocol for the making of surface-imprinted magnetic fluorescence beads viareversible addition-fragmentation chain transfer polymerization. The resulting composites were characterized by X-ray diffraction analysis, transmission electron microscopy, scanning electron microscopy, fluorescence spectroscopy, Fourier transform infrared spectroscopy, and energy dispersive spectroscopy. The as-synthesized beads exhibited homogeneous polymer films (thickness of about 5.7 nm), spherical shape, high fluorescence intensity and magnetic property (Magnetization (Ms) = 3.67 emu g-1). The hybrids bind the original template 17β-estradiol with an appreciable selectivity over structurally related compounds. In addition, the resulting hybrids performed without obvious deterioration after five repeated cycles. This study therefore demonstrates the potential of molecularly imprinted polymers for the recognition and separation of endocrine disrupting chemicals.In this study, we present a general protocol for the making of surface-imprinted magnetic fluorescence beads viareversible addition-fragmentation chain transfer polymerization. The resulting composites were characterized by X-ray diffraction analysis, transmission electron microscopy, scanning electron microscopy, fluorescence spectroscopy, Fourier transform infrared spectroscopy, and energy dispersive spectroscopy. The as-synthesized beads exhibited homogeneous polymer films (thickness of about 5.7 nm), spherical shape, high fluorescence intensity and magnetic property (Magnetization (Ms) = 3.67 emu g-1). The hybrids bind the original template 17β-estradiol with an appreciable selectivity over structurally related compounds. In addition, the resulting hybrids performed without obvious deterioration after five repeated cycles. This study therefore demonstrates the potential of molecularly imprinted polymers for the recognition and separation of endocrine disrupting chemicals. Electronic

  14. Synthesis of carboxylic block copolymers via reversible addition fragmentation transfer polymerization for tooth erosion prevention.

    Science.gov (United States)

    Lei, Y; Wang, T; Mitchell, J W; Qiu, J; Kilpatrick-Liverman, L

    2014-12-01

    Dental professionals are seeing a growing population of patients with visible signs of dental erosion. The approach currently being used to address the problem typically leverages the enamel protection benefits of fluoride. In this report, an alternative new block copolymer with a hydrophilic polyacrylic acid (PAA) block and a hydrophobic poly(methyl methacrylate) (PMMA) block was developed to similarly reduce the mineral loss from enamel under acidic conditions. This series of PMMA-b-PAA block copolymers was synthesized by reversible addition fragmentation transfer (RAFT) polymerization. Their structures were characterized by gel permeation chromatography (GPC) and (1)H nuclear magnetic resonance (NMR) spectra. The molar fractions of acrylic acid (AA) in the final block copolymer were finely controlled from 0.25 to 0.94, and the molecular weight (Mn) of PMMA-b-PAA was controlled from 10 kDa to 90 kDa. The binding capability of the block copolymer with hydroxyapatite (HAP) was investigated by ultraviolet-visible spectroscopy (UV-Vis) and Fourier transform infrared (FTIR) spectroscopy. FTIR spectra confirmed that the PMMA-b-PAA block copolymer could bind to HAP via bridging bidentate bonds. Both UV-Vis and FTIR spectra additionally indicated that a high polymer concentration and low solution pH favored the polymer binding to HAP. The erosion-preventing efficacy of the PMMA-b-PAA block copolymer in inhibiting HAP mineral loss was quantitatively evaluated by atomic absorption spectroscopy (AAS). Based on the results, polymer treatment reduced the amount of calcium released by 27% to 30% in comparison with the unprotected samples. Scanning electron microscope (SEM) observations indicated that PMMA-b-PAA polymer treatment protected enamel from acid erosion. This new amphiphilic block copolymer has significant potential to be integrated into dentifrices or mouthrinses as an alternative non-fluoride ingredient to reduce tooth erosion. PMID:25248611

  15. Reversible Addition Fragmentation Chain Transfer (RAFT) Polymerization in Undergraduate Polymer Science Lab

    Science.gov (United States)

    Nguyen, T. L. U.; Bennet, Francesca; Stenzel, Martina H.; Barner-Kowollik, Christopher

    2008-01-01

    This 8-hour experiment (spread over two 4-hour sessions) is designed to equip students with essential skills in polymer synthesis, particularly in synthesizing polymers of well-defined molecular weight. The experiment involves the synthesis and characterization of poly(vinyl neodecanoate) via living free radical polymerization, specifically the…

  16. RAFT microemulsion polymerization with surface-active chain transfer agent

    Science.gov (United States)

    El-Hedok, Ibrahim Adnan

    The work described in this dissertation focuses on enhancing the polymer nanoparticle synthesis using RAFT (reversible-addition fragmentation chain transfer) in microemulsion polymerization in order to achieve predetermined molecular weight with narrow molecular weight polydispersity. The hypothesis is that the use of an amphiphilic chain transfer agent (surface-active CTA) will confine the CTA to the surface of the particle and thermodynamically favor partitioning of the CTA between micelles and particles throughout the polymerization. Thus, the CTA diffusion from micelles to polymer particles would be minimized and the breadth of the CTA per particle distribution would remain low. We report the successful improved synthesis of poly(butyl acrylate), poly(ethyl acrylate), and poly(styrene) nanoparticles using the RAFT microemulsion polymerization with surface-active CTA. The polymerization kinetics, polymer characteristics and latex size experimental data are presented. The data analysis indicates that the CTA remains partitioned between the micelles and particles by the end of the polymerization, as expected. We also report the synthesis of well-defined core/shell poly(styrene)/poly(butyl acrylate) nanoparticle, having polydispersity index value of 1.1, using semi-continuous microemulsion polymerization with the surface-active CTA. The surface-active CTA restricts the polymerization growth to the surface of the particle, which facilitates the formation of a shell block co-polymers with each subsequent second monomer addition instead of discrete homopolymers. This synthesis method can be used to create a wide range of core/shell polymer nanoparticles with well-defined morphology, given the right feeding conditions.

  17. Molecular Imprinting of Silica Nanoparticle Surfaces via Reversible Addition-Fragmentation Polymerization for Optical Biosensing Applications

    Science.gov (United States)

    Oluz, Zehra; Nayab, Sana; Kursun, Talya Tugana; Caykara, Tuncer; Yameen, Basit; Duran, Hatice

    Azo initiator modified surface of silica nanoparticles were coated via reversible addition-fragmentation polymerization (RAFT) of methacrylic acid and ethylene glycol dimethacrylate using 2-phenylprop 2-yl dithobenzoate as chain transfer agent. Using L-phenylalanine anilide as template during polymerization led molecularly imprinted nanoparticles. RAFT polymerization offers an efficient control of grafting process, while molecularly imprinted polymers shows enhanced capacity as sensor. L-phenylalanine anilide imprinted silica particles were characterized by X-Ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM). Performances of the particles were followed by surface plasmon resonance spectroscopy (SPR) after coating the final product on gold deposited glass substrate against four different analogous of analyte molecules: D-henylalanine anilide, L-tyrosine, L-tryptophan and L-phenylalanine. Characterizations indicated that silica particles coated with polymer layer do contain binding sites for L-phenylalanine anilide, and are highly selective for the molecule of interest. This project was supported by TUBITAK (Project No:112M804).

  18. Exciton Transfer Integrals Between Polymer Chains

    CERN Document Server

    Barford, W

    2007-01-01

    The line-dipole approximation for the evaluation of the exciton transfer integral, $J$, between conjugated polymer chains is rigorously justified. Using this approximation, as well as the plane-wave approximation for the exciton center-of-mass wavefunction, it is shown analytically that $J \\sim L$ when the chain lengths are smaller than the separation between them, or $J\\sim L^{-1}$ when the chain lengths are larger than their separation, where $L$ is the polymer length. Scaling relations are also obtained numerically for the more realistic standing-wave approximation for the exciton center-of-mass wavefunction, where it is found that for chain lengths larger than their separation $J \\sim L^{-1.8}$ or $J \\sim L^{-2}$, for parallel or collinear chains, respectively. These results have important implications for the photo-physics of conjugated polymers and self-assembled molecular systems, as the Davydov splitting in aggregates and the F\\"orster transfer rate for exciton migration decreases with chain lengths l...

  19. Excitation transfer in stacked quantum dot chains

    International Nuclear Information System (INIS)

    Stacked InAs quantum dot chains (QDCs) on InGaAs/GaAs cross-hatch pattern (CHP) templates yield a rich emission spectrum with an unusual carrier transfer characteristic compared to conventional quantum dot (QD) stacks. The photoluminescent spectra of the controlled, single QDC layer comprise multiple peaks from the orthogonal QDCs, the free-standing QDs, the CHP, the wetting layers and the GaAs substrate. When the QDC layers are stacked, employing a 10 nm GaAs spacer between adjacent QDC layers, the PL spectra are dominated by the top-most stack, indicating that the QDC layers are nominally uncoupled. Under high excitation power densities when the high-energy peaks of the top stack are saturated, however, low-energy PL peaks from the bottom stacks emerge as a result of carrier transfers across the GaAs spacers. These unique PL signatures contrast with the state-filling effects in conventional, coupled QD stacks and serve as a means to quickly assess the presence of electronic coupling in stacks of dissimilar-sized nanostructures. (paper)

  20. Coherent state transfer via highly mixed quantum spin chains

    CERN Document Server

    Cappellaro, Paola; Ramanathan, Chandrasekhar

    2010-01-01

    Spin chains have been proposed as quantum wires in many quantum information processing architectures. Coherent transmission of quantum information over short distances is enabled by their internal dynamics, which drives the transport of single-spin excitations in perfectly polarized chains. Given the practical challenge of preparing the chain in a pure state, we propose to use a chain that is initially in the maximally mixed state. We compare the transport properties of pure and mixed-state chains, finding similarities that enable the experimental study of pure-state transfer by its simulation via mixed-state chains, and demonstrate protocols for the perfect transfer of quantum information in these chains. Remarkably, mixed-state chains allow the use of Hamiltonians which do not preserve the total number of excitations, and which are more readily obtainable from the naturally occurring magnetic dipolar interaction. We propose experimental implementations using solid-state nuclear magnetic resonance and defect...

  1. Modelling proton transfer in water molecule chains

    CERN Document Server

    Korzhimanov, Artem; Shutova, Tatiana; Samuelsson, Goran

    2011-01-01

    The process of protons transport in molecular water chains is of fundamental interest for many biological systems. Although many features of such systems can be analyzed using large-scale computational modeling, other features are better understood in terms of simplified model problems. Here we have tested, analytically and numerically, a model describing the classical proton hopping process in molecular water chains. In order to capture the main features of the proton hopping process in such molecular chains, we use a simplified model for our analysis. In particular, our discrete model describes a 1D chain of water molecules situated in an external protein channel structure, and each water molecule is allowed to oscillate around its equilibrium point in this system, while the protons are allowed to move along the line of neighboring oxygen atoms. The occurrence and properties of nonlinear solitary transport structures, allowing for much faster proton transport, are discussed, and the possible implications of...

  2. Controlled Quantum State Transfer in a Spin Chain

    CERN Document Server

    Gong, J; Brumer, Paul; Gong, Jiangbin

    2007-01-01

    Control of the transfer of quantum information encoded in quantum wavepackets moving along a spin chain is demonstrated. Specifically, based on a relationship with control in a paradigm of quantum chaos, it is shown that wavepackets with slow dispersion can automatically emerge from a class of initial superposition states involving only a few spins, and that arbitrary unspecified travelling wavepackets can be nondestructively stopped and later relaunched with perfection. The results establish an interesting application of quantum chaos studies in quantum information science.

  3. Synthesis of Carboxylic Block Copolymers via Reversible Addition Fragmentation Transfer Polymerization for Tooth Erosion Prevention

    OpenAIRE

    Lei, Y.; Wang, T.; Mitchell, J. W.; Qiu, J.; Kilpatrick-Liverman, L.

    2014-01-01

    Dental professionals are seeing a growing population of patients with visible signs of dental erosion. The approach currently being used to address the problem typically leverages the enamel protection benefits of fluoride. In this report, an alternative new block copolymer with a hydrophilic polyacrylic acid (PAA) block and a hydrophobic poly(methyl methacrylate) (PMMA) block was developed to similarly reduce the mineral loss from enamel under acidic conditions. This series of PMMA-b-PAA blo...

  4. Organic cleanliness of the Mars Science Laboratory sample transfer chain.

    Science.gov (United States)

    Blakkolb, B; Logan, C; Jandura, L; Okon, A; Anderson, M; Katz, I; Aveni, G; Brown, K; Chung, S; Ferraro, N; Limonadi, D; Melko, J; Mennella, J; Yavrouian, A

    2014-07-01

    One of the primary science goals of the Mars Science Laboratory (MSL) Rover, Curiosity, is the detection of organics in Mars rock and regolith. To achieve this, the Curiosity rover includes a robotic sampling system that acquires rock and regolith samples and delivers it to the Sample Analysis at Mars (SAM) instrument on board the rover. In order to provide confidence that any significant organics detection result was Martian and not terrestrial in origin, a requirement was levied on the flight system (i.e., all sources minus the SAM instrument) to impart no more than 36 parts per billion (ppb by weight) of total reduced carbon terrestrial contamination to any sample transferred to the SAM instrument. This very clean level was achieved by a combination of a rigorous contamination control program on the project, and then using the first collected samples for a "dilution cleaning" campaign of the sample chain prior to delivering a sample to the SAM instrument. Direct cleanliness assays of the sample-contacting and other Flight System surfaces during pre-launch processing were used as inputs to determine the number of dilution cleaning samples needed once on Mars, to enable delivery of suitably clean samples to the SAM experiment. Taking into account contaminant redistribution during launch thorough landing of the MSL on Mars, the amount of residue present on the sampling hardware prior to the time of first dilution cleaning sample acquisition was estimated to be 60 ng/cm(2) on exposed outer surfaces of the sampling hardware and 20 ng/cm(2) on internal sample contacting surfaces; residues consisting mainly of aliphatic hydrocarbons and esters. After three dilution cleaning samples, estimated in-sample contamination level for the first regolith sample delivered to the SAM instrument at the Gale Crater "Rocknest" site was bounded at ≤10 ppb total organic carbon. A Project decision to forego ejecting the dilution cleaning sample and instead transfer the first drill

  5. Organic cleanliness of the Mars Science Laboratory sample transfer chain.

    Science.gov (United States)

    Blakkolb, B; Logan, C; Jandura, L; Okon, A; Anderson, M; Katz, I; Aveni, G; Brown, K; Chung, S; Ferraro, N; Limonadi, D; Melko, J; Mennella, J; Yavrouian, A

    2014-07-01

    One of the primary science goals of the Mars Science Laboratory (MSL) Rover, Curiosity, is the detection of organics in Mars rock and regolith. To achieve this, the Curiosity rover includes a robotic sampling system that acquires rock and regolith samples and delivers it to the Sample Analysis at Mars (SAM) instrument on board the rover. In order to provide confidence that any significant organics detection result was Martian and not terrestrial in origin, a requirement was levied on the flight system (i.e., all sources minus the SAM instrument) to impart no more than 36 parts per billion (ppb by weight) of total reduced carbon terrestrial contamination to any sample transferred to the SAM instrument. This very clean level was achieved by a combination of a rigorous contamination control program on the project, and then using the first collected samples for a "dilution cleaning" campaign of the sample chain prior to delivering a sample to the SAM instrument. Direct cleanliness assays of the sample-contacting and other Flight System surfaces during pre-launch processing were used as inputs to determine the number of dilution cleaning samples needed once on Mars, to enable delivery of suitably clean samples to the SAM experiment. Taking into account contaminant redistribution during launch thorough landing of the MSL on Mars, the amount of residue present on the sampling hardware prior to the time of first dilution cleaning sample acquisition was estimated to be 60 ng/cm(2) on exposed outer surfaces of the sampling hardware and 20 ng/cm(2) on internal sample contacting surfaces; residues consisting mainly of aliphatic hydrocarbons and esters. After three dilution cleaning samples, estimated in-sample contamination level for the first regolith sample delivered to the SAM instrument at the Gale Crater "Rocknest" site was bounded at ≤10 ppb total organic carbon. A Project decision to forego ejecting the dilution cleaning sample and instead transfer the first drill

  6. Preparation of End Grafted Polyacrylonitrile Brushes through Surface Confined Radical Chain Transfer Reaction

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    End grafted polyacrylonitrile (PAN) brush was prepared through surface initiated polymerization via the chain transfer process. The thiol-terminated monolayer and PAN brushes were characterized by FTIR, X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), ellipsometry and contact angle measurements ete. It is demonstrated that radical chain transfer reaction and surface initiated precipitate polymerization can be used to prepare end-grafted polymer brushes.

  7. Innovations and Knowledge Transfer for the Food Supply Chain Sustainability: Challenges in the Czech Dairy Industry

    OpenAIRE

    Ratinger, Tomas; Bošková, Iveta

    2013-01-01

    A mobilisation of research, knowledge transfer and innovation to deal with the current challenges as raising world food demand while protecting natural resources is a priority area of the EU. The effective knowledge transfer and innovation activities in the agri-food supply chain may push all producers in the vertical to improve their competitiveness while saving resources. In the paper we examine the current level of innovation activities and knowledge transfer in milk processing industry in...

  8. Spin Chains and Electron Transfer at Stepped Silicon Surfaces.

    Science.gov (United States)

    Aulbach, J; Erwin, S C; Claessen, R; Schäfer, J

    2016-04-13

    High-index surfaces of silicon with adsorbed gold can reconstruct to form highly ordered linear step arrays. These steps take the form of a narrow strip of graphitic silicon. In some cases--specifically, for Si(553)-Au and Si(557)-Au--a large fraction of the silicon atoms at the exposed edge of this strip are known to be spin-polarized and charge-ordered along the edge. The periodicity of this charge ordering is always commensurate with the structural periodicity along the step edge and hence leads to highly ordered arrays of local magnetic moments that can be regarded as "spin chains." Here, we demonstrate theoretically as well as experimentally that the closely related Si(775)-Au surface has--despite its very similar overall structure--zero spin polarization at its step edge. Using a combination of density-functional theory and scanning tunneling microscopy, we propose an electron-counting model that accounts for these differences. The model also predicts that unintentional defects and intentional dopants can create local spin moments at Si(hhk)-Au step edges. We analyze in detail one of these predictions and verify it experimentally. This finding opens the door to using techniques of surface chemistry and atom manipulation to create and control silicon spin chains. PMID:26974012

  9. Spin Chains and Electron Transfer at Stepped Silicon Surfaces.

    Science.gov (United States)

    Aulbach, J; Erwin, S C; Claessen, R; Schäfer, J

    2016-04-13

    High-index surfaces of silicon with adsorbed gold can reconstruct to form highly ordered linear step arrays. These steps take the form of a narrow strip of graphitic silicon. In some cases--specifically, for Si(553)-Au and Si(557)-Au--a large fraction of the silicon atoms at the exposed edge of this strip are known to be spin-polarized and charge-ordered along the edge. The periodicity of this charge ordering is always commensurate with the structural periodicity along the step edge and hence leads to highly ordered arrays of local magnetic moments that can be regarded as "spin chains." Here, we demonstrate theoretically as well as experimentally that the closely related Si(775)-Au surface has--despite its very similar overall structure--zero spin polarization at its step edge. Using a combination of density-functional theory and scanning tunneling microscopy, we propose an electron-counting model that accounts for these differences. The model also predicts that unintentional defects and intentional dopants can create local spin moments at Si(hhk)-Au step edges. We analyze in detail one of these predictions and verify it experimentally. This finding opens the door to using techniques of surface chemistry and atom manipulation to create and control silicon spin chains.

  10. Theory of quantum energy transfer in spin chains: From superexchange to ballistic motion

    OpenAIRE

    Yu, Claire X.; Wu, Lian-Ao; Segal, Dvira

    2011-01-01

    Quantum energy transfer in a chain of two-level (spin) units, connected at its ends to two thermal reservoirs, is analyzed in two limits: (i) In the off-resonance regime, when the characteristic subsystem excitation energy gaps are larger than the reservoirs frequencies, or the baths temperatures are low. (ii) In the resonance regime, when the chain excitation gaps match populated bath modes. In the latter case the model is studied using a master equation approach, showing that the dynamics i...

  11. Copper transfer and influence on a marine food chain

    Energy Technology Data Exchange (ETDEWEB)

    Edding, M.; Tala, F. [Universidad Catolica del Norte, Coquimbo (Chile)

    1996-12-31

    Copper is an essential element, required for normal growth by all plants and animals; and a regular constituent in the environment (Lewis and Cave 1982; Lewis 1994). This heavy metal is an essential micronutrient that at higher concentrations can be deleterious to algae and other aquatic biota (Chang and Sibley 1993). Copper toxicity to algae depends upon the individual species, their physiological and environmental conditions, and the chemical forms of metal in the medium (Sunda and Gullard 1976). When copper is accumulated by phytoplankton it can be transferred and may produce toxic effects on zooplankton (Wikfors and Ukeles 1982). Different species of microalgae present different capacities of resistance to copper. Cyanophyceae pre-cultured in a Cu-enriched medium (635 {mu}gCu{center_dot}L{sup {minus}1}) showed an EC{sub 50} that could reach 318 {mu}gCu{center_dot}L{sup {minus}1} for Plectonema radiosum and 339 {mu}gCu{center_dot}L{sup {minus}1} in Phormidium sp. (Takamura et al. 1990). Scenedesmus, Selenastrum and Chlorella were reported able to accumulate copper and other metal ions with an efficiency of 67-98% (Brady et al. 1994). Also, Dunaliella resisted concentrations form 0.38 mgCu{center_dot}L{sup {minus}1} (D. minuta) up to 50.8 mgCu{center_dot}L{sup {minus}1} (D. acidophila), depending on the pH of the medium (Grimmler et al. 1991). One the microalgae are copper-enriched, the copper that is part of the cell can be transferred to the surrounding water and to its predator producing uncertain effects. This study observed the effect of copper on the growth of Dunaliella tertiolecta and Isochrysis galbana that are currently used as food for hatchery-grown scallop larvae (Argopecten purpuratus). We observed the path of copper form the water column into the microalgal cell and the effect of copper-enriched food on the scallop larvae. 16 refs., 3 figs., 2 tabs.

  12. Bioaccumulation and food chain transfer of corrosion products from radioactive stainless steel

    Energy Technology Data Exchange (ETDEWEB)

    Young, J.S.

    1986-07-01

    Two sets of experiments were conducted to determine if corrosion products from radioactive Type 347 stainless steel could be biologically transferred from sediment through a marine food chain, and whether corrosion products dissolved in seawater could be bioaccumulated and then eliminated. Corrosion products containing /sup 60/Co and /sup 63/Ni from the radioactive stainless steel were introduced into marine sediments. Infaunal polychaete worms exposed to these sediments bioaccumulated the radionuclides. The feeding of these worms to shrimp and fish resulted in a trophic transfer of the radioactive products across a one-step food chain. The magnitude of the transfers are described in terms of transfer factors. Dissolved corrosion products as measured by the radionuclides were also bioaccumulated by shrimp and fish concentrating more than fish. Concentration factors were calculated.

  13. Bioaccumulation and food chain transfer of corrosion products from radioactive stainless steel

    International Nuclear Information System (INIS)

    Two sets of experiments were conducted to determine if corrosion products from radioactive Type 347 stainless steel could be biologically transferred from sediment through a marine food chain, and whether corrosion products dissolved in seawater could be bioaccumulated and then eliminated. Corrosion products containing 60Co and 63Ni from the radioactive stainless steel were introduced into marine sediments. Infaunal polychaete worms exposed to these sediments bioaccumulated the radionuclides. The feeding of these worms to shrimp and fish resulted in a trophic transfer of the radioactive products across a one-step food chain. The magnitude of the transfers are described in terms of transfer factors. Dissolved corrosion products as measured by the radionuclides were also bioaccumulated by shrimp and fish concentrating more than fish. Concentration factors were calculated

  14. Transfer of 137Cs through the food chain to man

    International Nuclear Information System (INIS)

    Deposition, concentrations in diet, and body burdens of 137Cs have been measured since 1954 at various sites throughout the world. This report is a compilation and updating of various fallout 137Cs measurements and an interpretation of transfer properties of 137Cs from deposition to diet and from diet to man. An empirical model is used to correlate deposition and diet data. Direct foliar contamination, stored food supplies, and uptake from soil contribute to the dietary levels of 137Cs. The accumulation of 137Cs by man is described by a single exponential model. The inferred biological half-times, 200 to 400 days, are somewhat greater than the half-time of about 100 days obtained from shorter term studies. Differences in body burdens due to sex, age, and weight are discussed. During the period 1954 to 1974, the internal dose from fallout 137Cs, based on average body burdens, is estimated to be 4 to 5 percent of the 21 year radiation dose from 40K

  15. Long-range doublon transfer in a dimer chain induced by topology and ac fields

    Science.gov (United States)

    Bello, M.; Creffield, C. E.; Platero, G.

    2016-01-01

    The controlled transfer of particles from one site of a spatial lattice to another is essential for many tasks in quantum information processing and quantum communication. In this work we study how to induce long-range transfer between the two ends of a dimer chain, by coupling states that are localized just on the chain’s end-points. This has the appealing feature that the transfer occurs only between the end-points – the particle does not pass through the intermediate sites–making the transfer less susceptible to decoherence. We first show how a repulsively bound-pair of fermions, known as a doublon, can be transferred from one end of the chain to the other via topological edge states. We then show how non-topological surface states of the familiar Shockley or Tamm type can be used to produce a similar form of transfer under the action of a periodic driving potential. Finally we show that combining these effects can produce transfer by means of more exotic topological effects, in which the driving field can be used to switch the topological character of the edge states, as measured by the Zak phase. Our results demonstrate how to induce long range transfer of strongly correlated particles by tuning both topology and driving. PMID:26932406

  16. Screening models to predict food-chain transfer of environmental toxicants

    International Nuclear Information System (INIS)

    The objectives of the research effort were to determine transfer coefficients to milk, beef, eggs, and poultry meat of six radionuclides for which transfer coefficients were either undetermined or based upon secondary data. The radionuclides were isotopes of Tc, Mo, Te, Ba, Zr, and Nb. In addition, 131I was used in experiments with hens to determine egg and poultry meat transfer coefficients. The new information on transfer coefficients obtained during this project indicates that, in some cases, lower values are appropriate and that those currently in use may provide an overestimate of the risks to man from the animal food chain. The objective of the second phase of this research was to provide information to clarify the physiological parameters that control transfer of radionuclides to animal food products. The data from the first phase has been published but this data has not appeared in the literature and thus is presented here in some detail. 10 refs., 4 figs., 6 tabs

  17. Influence of dispersants on trophic transfer of petroleum hydrocarbons in a marine food chain

    Energy Technology Data Exchange (ETDEWEB)

    Wolfe, M. F.; Schwartz, G. J. B.; Singaram, S.; Tjeerdema, R. S. [California Univ., Santa Cruz, CA (United States). Dept. of Chemistry; Mielbrecht, E. E. [California Univ., Santa Cruz, CA (United States). Inst. of Marine Sciences; Sowby, M. L. [California State Dept. of Fish and Game, Sacramento, CA (United States)

    1997-10-01

    Experiments were conducted to determine the impact of dispersing agents on petroleum hydrocarbons (PH) bioavailability and trophic transfer in primary levels of a marine food chain. Uptake, bioaccumulation and metabolic transformation of a model PH, ({sup 1}4C)naphthalene, were measured and compared with Prudhoe Bay Crude Oil (PBCO) dispersed with Corexit 9527, and undispersed preparations of PBCO. The model food chain consisted of a primary algae producer and a primary rotifer consumer. Results showed that uptake of naphthalene increased significantly in the presence of a dispersant in algae. A significant increase in uptake was also recorded in rotifers via trophic transfer. Trophic transfer played a significant, sometimes even dominant, role in uptake and bioaccumulation. 27 refs., 6 figs.

  18. A general model for the transfer of radioactive materials in terrestrial food chains

    International Nuclear Information System (INIS)

    A general methodology for modelling the transfer of radionuclides in the food chains to man is described. The models are dynamic in nature so that the long-term time dependence of processes in environmental materials can be represented, for example, the build-up of activity concentrations in soils during continuous deposition from atmosphere. Modules for radionuclide migration are described in well-mixed (cultivated) soil and undisturbed soil (pasture). The methods by which the transfer coefficients used in plant and animal modules are derived are also given. The foodstuffs considered are those derived from green vegetables, grain, and root vegetables together with meat and liver products from the cow and sheep and cow dairy products. The dynamic model permits the time dependence of food chain transfer processes to be represented for different land contamination scenarios; in particular, the model can be adapted to represent behaviour following a single deposit. Using the sensitivity of results to the variation of transfer parameters the model can be used to determine the parts of the food chain where improved data would be most effective in increasing the reliability of radiological assessments; a worked example is given. (author)

  19. Identification and evaluation of modularization practices in an automotive supplier: progressivity analysis of transferring activities in the supply chain

    OpenAIRE

    Evandro Prieto; Paulo A. Cauchick Miguel

    2013-01-01

    The automotive value chain has more and more been making room to a strategy of which activities of product design and production have been transferred to the module suppliers. The transfer of value-added activities occurs from assembler to the module suppliers. The former assume the role of integrators within the supply chain. The supply chain participants have started to strengths their competencies in order to obtain advantages in the economy of scale and scope. In this context, the present...

  20. Electrode assemblies composed of redox cascades from microbial respiratory electron transfer chains

    Energy Technology Data Exchange (ETDEWEB)

    Gates, Andrew J. [Univ. of East Anglia, Norwich (United Kingdom); Marritt, Sophie [Univ. of East Anglia, Norwich (United Kingdom); Bradley, Justin [Univ. of East Anglia, Norwich (United Kingdom); Shi, Liang [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); McMillan, Duncan G. [Univ. of Leeds (United Kingdom); Jeuken, Lars J. [Univ. of Leeds (United Kingdom); Richardson, David [Univ. of East Anglia, Norwich (United Kingdom); Butt, Julea N. [Univ. of East Anglia, Norwich (United Kingdom)

    2013-10-01

    Respiratory and photosynthetic electron transfer chains are dependent on vectorial electron transfer through a series of redox proteins. Examples include electron transfer from NapC to NapAB nitrate reductase in Paracoccus denitrificans and from CymA to Fcc3 (flavocytochrome c3) fumarate reductase in Shewanella oneidensis MR-1. In the present article, we demonstrate that graphite electrodes can serve as surfaces for the stepwise adsorption of NapC and NapAB, and the stepwise adsorption of CymA and Fcc3. Aspects of the catalytic properties of these assemblies are different from those of NapAB and Fcc3 adsorbed in isolation. We propose that this is due to the formation of NapC-NapAB and of CymA-Fcc3 complexes that are capable of supporting vectorial electron transfer.

  1. Universal scheme for finite-probability perfect transfer of arbitrary multispin states through spin chains

    Energy Technology Data Exchange (ETDEWEB)

    Man, Zhong-Xiao, E-mail: zxman@mail.qfnu.edu.cn [Shandong Provincial Key Laboratory of Laser Polarization and Information Technology, Department of Physics, Qufu Normal University, Qufu 273165 (China); An, Nguyen Ba, E-mail: nban@iop.vast.ac.vn [Center for Theoretical Physics, Institute of Physics, Vietnam Academy of Science and Technology (VAST), 18 Hoang Quoc Viet, Cau Giay, Hanoi (Viet Nam); Xia, Yun-Jie, E-mail: yjxia@mail.qfnu.edu.cn [Shandong Provincial Key Laboratory of Laser Polarization and Information Technology, Department of Physics, Qufu Normal University, Qufu 273165 (China); Kim, Jaewan, E-mail: jaewan@kias.re.kr [School of Computational Sciences, Korea Institute for Advanced Study, Hoegiro 85, Dongdaemun-gu, Seoul 130-722 (Korea, Republic of)

    2014-12-15

    In combination with the theories of open system and quantum recovering measurement, we propose a quantum state transfer scheme using spin chains by performing two sequential operations: a projective measurement on the spins of ‘environment’ followed by suitably designed quantum recovering measurements on the spins of interest. The scheme allows perfect transfer of arbitrary multispin states through multiple parallel spin chains with finite probability. Our scheme is universal in the sense that it is state-independent and applicable to any model possessing spin–spin interactions. We also present possible methods to implement the required measurements taking into account the current experimental technologies. As applications, we consider two typical models for which the probabilities of perfect state transfer are found to be reasonably high at optimally chosen moments during the time evolution. - Highlights: • Scheme that can achieve perfect quantum state transfer is devised. • The scheme is state-independent and applicable to any spin-interaction models. • The scheme allows perfect transfer of arbitrary multispin states. • Applications to two typical models are considered in detail.

  2. Transfer of Metals in Food Chain: An Example with Copper and Lettuce

    Science.gov (United States)

    Vincevica-Gaile, Zane; Klavins, Maris

    2012-12-01

    Present study investigated the possible transfer of metals in the food chain (from soil to edible plants). The experiment was done with lettuce Lactuca sativa grown in different types of soil contaminated with copper (Cu2+) in various concentrations, with or without addition of humic substances. The highest content of copper was detected in lettuce samples grown in soils with lower levels of organic matter, thus indicating the importance of soil organics in metal transfer routes and accumulation rates in plants. It was found that copper accumulation in lettuce grown in contaminated soils can be significantly reduced by the addition of humic substances.

  3. Removal of phase transfer agent leads to restricted dynamics of alkyl chains in monolayer protected clusters

    Indian Academy of Sciences (India)

    V R Rajeev Kumar; R Mukhopadhyay; T Pradeep

    2008-11-01

    The effect of phase transfer agent in the dynamics of monolayer protected gold nanoparticles has been investigated by infrared (IR) and nuclear magnetic resonance (NMR) spectroscopies. The experiments were performed with octadecane thiol and dodecane thiol protected gold nanoparticles. The materials prepared were characterized by UV-Visible spectroscopy, transmission electron microscopy and IR spectroscopy. Repeated purification of the monolayer protected gold clusters made the alkyl chains defect-free. Such effects are reflected in the infrared spectra. Interdigitation of the monolayers that followed the purification leads to alkyl chains with limited mobility. This was reflected in 13C and 1H NMR linewidths. The NMR measurements indicate that the removal of phase transfer agent affects the dynamics of isolated clusters and those with interdigitated monolayers in different ways.

  4. Modelling of radiocesium transfer in the lichen-reindeer/caribou-wolf food chain

    Directory of Open Access Journals (Sweden)

    D. F. Holleman

    1990-09-01

    Full Text Available The environmental contaminate radiocesium (cesium-137 has been shown to be of value as a marker in food selection and intake studies. Its greatest potential value as a food marker is in the subarctic/arctic regions, particularly in the lichen to reindeer/caribou to wolf food chain. A kinetic model describing the movement of radiocesium through the food chain has been developed using the SAAM computer program and is presented here. The program has been written so that the various paramenters affecting the transfer of radiocesium in the food chain can be altered more realistically to describe the system being modeled. The values of the parameters as given in this example are realistic for interior Alaska, however caution should be exercised in the application of the present results to regions that may be vastly different from the Alaskan interior without first evaluating the parameters and assumptions of the model.

  5. Spin-state transfer in laterally coupled quantum-dot chains with disorders

    International Nuclear Information System (INIS)

    Quantum dot arrays are a promising medium for transferring quantum information between two distant points without resorting to mobile qubits. Here we study the two most common disorders, namely hyperfine interaction and exchange coupling fluctuations, in quantum dot arrays and their effects on quantum communication through these chains. Our results show that the hyperfine interaction is more destructive than the exchange coupling fluctuations. The average optimal time for communication is not affected by any disorder in the system and our simulations show that antiferromagnetic chains are much more resistive than the ferromagnetic ones against both kind of disorders. Even when time modulation of a coupling and optimal control is employed to improve the transmission, the antiferromagnetic chain performs much better. We have assumed the quasistatic approximation for hyperfine interaction and time-dependent fluctuations in the exchange couplings. Particularly for studying exchange coupling fluctuations we have considered the static disorder, white noise, and 1/f noise.

  6. Ultrafast energy transfer from rigid, branched side-chains into a conjugated, alternating copolymer

    Energy Technology Data Exchange (ETDEWEB)

    Griffin, Graham B.; Rolczynski, Brian S.; Linkin, Alexander; McGillicuddy, Ryan D.; Engel, Gregory S., E-mail: gsengel@uchicago.edu [Department of Chemistry, The James Franck Institute, Institute for Biophysical Dynamics, The University of Chicago, Chicago, Illinois 60637 (United States); Lundin, Pamela M. [Department of Chemical Engineering, Stanford University, Stauffer III, 381 North-South Mall, Stanford, California 94305 (United States); A. R. Smith Department of Chemistry, Appalachian State University, 417 CAP Building, 525 Rivers Street, Boone, North Carolina 28608 (United States); Bao, Zhenan [Department of Chemical Engineering, Stanford University, Stauffer III, 381 North-South Mall, Stanford, California 94305 (United States)

    2014-01-21

    We present the synthesis and characterization of a benzodithiophene/thiophene alternating copolymer decorated with rigid, singly branched pendant side chains. We characterize exciton migration and recombination dynamics in these molecules in tetrahydrofuran solution, using a combination of static and time-resolved spectroscopies. As control experiments, we also measure electronic relaxation dynamics in isolated molecular analogues of both the side chain and polymer moieties. We employ semi-empirical and time-dependent density functional theory calculations to show that photoexcitation of the decorated copolymer using 395 nm laser pulses results in excited states primarily localized on the pendant side chains. We use ultrafast transient absorption spectroscopy to show that excitations are transferred to the polymer backbone faster than the instrumental response function, ∼250 fs.

  7. Technology Transfer in the Global Automotive Value Chain. Lessons from the Turkish Automotive Industry

    OpenAIRE

    M. Teoman Pamukçu; Alper Sönmez

    2011-01-01

    The automotive industry is one of the main contributors to value added, employment and exports of the Turkish economy and it has undergone major changes since the mid-nineties. Most of the automotive manufacturers in Turkey are either joint ventures or wholly-owned affiliates of multinational companies. Literature on global value chains point to the possibility of technology transfer occurring through backward linkages from automotive manufacturers to their suppliers. We test for the existenc...

  8. A model for the chain-to-plane charge transfer in YBa2Cu3O6+x

    Institute of Scientific and Technical Information of China (English)

    V.M.Matic; N.Dj.Lazarov; M.Milic

    2012-01-01

    A model for the chain-to-plane charge transfer is proposed to account for the two plateaus,at 60 K and at 90 K,of the Tc(x) characteristics of the YBa2Cu3O6+x high-Tc superconductor.It is assumed that the number of holes transferred from a CuO chain of length l to two nearby CuO2 sheets is proportional to l (that is,to the number of oxygen atoms in the chain),if the chain length is greater than,or equal to,a certain critical chain length,lcr,that is required to trigger the charge transfer process.No holes are assumed to have been transferred from chains of length l < lcr.The calculated Tc(x) dependence is found to be in excellent agreement with the experimentally reported Tc(x).The critical chain length parameter is estimated to be equal to lcr =11 (eleven oxygen atoms in a chain),which is a greater value than that obtained in the previously proposed model for the chain-to plane charge transfer (lcr =4).The results obtained out of the proposed model are briefly discussed.

  9. Effect of feeding selectivity on the transfer of methylmercury through experimental marine food chains.

    Science.gov (United States)

    Zhang, Peng; Sun, Jingxian; Chen, Jieru; Wei, Jie; Zhao, Wen; Liu, Qing; Sun, Huiling

    2013-08-01

    The present study established an experimental marine food chain of three levels (microalgae → zooplankton → fish) to investigate the effect of feeding selectivity on the transfer of methylmercury (MeHg) through the food chain. Total Hg concentrations in Chlorella sp., Nitzschia closterium and Isochrysis galbana exposed to 1 μg L(-1) MeHg for three days were 27.91, 32.74 and 40.03 μg g(-1) respectively and were significantly different (p Moina mongolica and Artemia sp. primarily selected Chlorella sp. as the sole diet, though the Artemia sp. partly grazed on I. galbana as well. Harpacticus uniremis, however, preferred to graze N. closterium and I. galbana and avoided Chlorella sp. The varying concentration of Hg in the microalgae species as well as the selectivity of zooplankton to the algal diet resulted in varying Hg accumulation in three zooplankton species (M. mongolica P. olivaceus > F. rubripes with total Hg concentrations of 0.0042, 0.0031 and 0.0020 μg g(-1), respectively). These investigations suggested feeding selectivity plays a key role in the transfer of MeHg along marine food chains. PMID:23702096

  10. Revealing various coupling of electron transfer and proton pumping in mitochondrial respiratory chain.

    Science.gov (United States)

    Sun, Fei; Zhou, Qiangjun; Pang, Xiaoyun; Xu, Yingzhi; Rao, Zihe

    2013-08-01

    Cellular respiration is the process that releases energy from food and supplies energy for life processes. The mitochondrial respiratory chain is the final and most important step for cellular respiration and is located on the inner membrane of mitochondrion and comprises four large trans-membrane protein complexes (respiratory chain Complexes I, II, III and IV) as well as ubiquinone between Complexes I/II and III and cytochrome c between Complexes III and IV. The function of mitochondrial respiratory chain is biological oxidation by transferring electrons from NADH and succinate to oxygen and then generating proton gradient across the inner membrane. Such proton gradient is utilized by ATP synthase (ATPase, also called as Complex V) to produce energy molecules ATP. Structural studies of mitochondrial respiratory membrane protein complexes are important to understand the mechanism of electron transfer and the redox-coupled proton translocation across the inner membrane. Here, according to the time line, we reviewed the great achievements on structural studies of mitochondrial respiratory complexes in the past twenty years as well as the recent research progresses on the structures of mitochondrial respiratory supra-complexes.

  11. Transfer of some Chernobyl fallout nuclides in the animal-product food chain

    International Nuclear Information System (INIS)

    One of the most important tasks after the Chernobyl accident was the tracing of radionuclides into the food chain because of the acute interest in view of radiation protection considerations and of the fundamental significance to extend the knowledge on consequences of an accidental release. In this context five experiments have been performed during the last two years to investigate the transfer of radiocesium from grass into milk and meat of dairy cows. The first experiment, which was started immediately after the accident, involved 10 stable-kept cows fed with the freshly contaminated grass. Cs-transfer from grass into milk was found to be considerably lower than expected. After the starting phase of one week the mean transfer factor milk/grass for Cs-134 and Cs-137 leveled at 3.2.10-3 d/kg during the second week. This interesting result gave rise to four additional experiments, to study the Cs-transfer during the following feeding periods applying grass of fallout and root-uptake contamination

  12. Transfer data for radio-cesium in the food chain feed/meat

    International Nuclear Information System (INIS)

    It is necessary to have some knowledge of the behaviour of radioactive material in the food chain to be able to assess the radiation exposure of humans via the ingestion path way. The transfer factor has to be defined precisely because there is a linear dependence of the radiation dose on the transfer factor in the mathematical models for calculating the annual radiation doses. Knowledge of the animal-specific cesium retention, of the biological half-life as well as of the distribution system is required for an accurate calculation of the transfer-data of the particularly important radionuclide cesium 137. After having studied the original literature thoroughly the following transfer factors have been found as an average: cattle 0.03 +- 0.02, calf 0.43 +- 0.06, goat 0.20, sheep 0.11 +- 0.02, swine 0.26 +- 0.01, chicken 3.23 +- 1.41, reindeer 0.31 +- 0.07. (MG)

  13. Entanglement Transfer and Periodic Sudden Death Phenomenon in Two Parallel 1D Spin Chains of Quantum Spin Network

    Institute of Scientific and Technical Information of China (English)

    WANG Zhao-Ming; SHAO Bin; ZOU Jian

    2007-01-01

    We investigate the entanglement transfer in two parallel 1D spin chains of a quantum spin network,and show that the perfect entanglement transfer can be realized at some special times.In addition,the so-called 'sudden death' phenomenon of entanglement is found in the spin network system.

  14. Polonium ({sup 210}Po) and lead ({sup 210}Pb) in marine organisms and their transfer in marine food chains

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, Fernando P., E-mail: carvalho@itn.p [Instituto Tecnologico e Nuclear, Departamento de Proteccao Radiologica e Seguranca Nuclear, E.N. 10, 2686-953 Sacavem (Portugal)

    2011-05-15

    The determination of {sup 210}Po and {sup 210}Pb was performed in marine organisms from the seashore to abyssal depths, encompassing a plethora of species from the microscopic plankton to the sperm whale. Concentrations of those radionuclides ranged from low values of about 5 x 10{sup -1} Bq kg{sup -1} (wet wt.) in jellyfish, to very high values of about of 3 x 10{sup 4} Bq kg{sup -1} (wet wt.) in the gut walls of sardines, with a common pattern of {sup 210}Po > {sup 210}Pb.These radionuclides are primarily absorbed from water and concentrated by phyto- and microzooplankton, and then are transferred to the next trophic level along marine food chains. Investigation in epipelagic, mesopelagic, bathypelagic and abyssobenthic organisms revealed that {sup 210}Po is transferred in the marine food webs with transfer factors ranging from 0.1 to 0.7, and numerically similar to those of the energy transfer in the marine food chains. As {sup 210}Po preferentially binds to amino acids and proteins, its transfer in food chains likely traces protein transfer and, thus, {sup 210}Po transfer factors are similar to ecotrophic coefficients. {sup 210}Pb is transferred less efficiently in marine food chains and this contributes to increased {sup 210}Po:{sup 210}Pb activity ratios in some trophic levels.

  15. Preparation of polystyrene brush film by radical chain-transfer polymerization and micromechanical properties

    Science.gov (United States)

    Zhao, Jing; Chen, Miao; An, Yanqing; Liu, Jianxi; Yan, Fengyuan

    2008-12-01

    A radical chain-transfer polymerization technique has been applied to graft-polymerize brushes of polystyrene (PSt) on single-crystal silicon substrates. 3-Mercapto-propyltrimethoxysilane (MPTMS), as a chain-transfer agent for grafting, was immobilized on the silicon surface by a self-assembling process. The structure and morphology of the graft-functionalized silicon surfaces were characterized by the means of contact-angle measurement, ellipsometric thickness measurement, Fourier transformation infrared (FTIR) spectroscopy, and atomic force microscopy (AFM). The nanotribological and micromechanical properties of the as-prepared polymer brush films were investigated by frictional force microscopy (FFM), force-volume analysis and scratch test. The results indicate that the friction properties of the grafted polymer films can be improved significantly by the treatment of toluene, and the chemically bonded polystyrene film exhibits superior scratch resistance behavior compared with the spin-coated polystyrene film. The resultant polystyrene brush film is expected to develop as a potential lubrication coating for microelectromechanical systems (MEMS).

  16. Carrier transfer in vertically stacked quantum ring-quantum dot chains

    Science.gov (United States)

    Mazur, Yu. I.; Lopes-Oliveira, V.; de Souza, L. D.; Lopez-Richard, V.; Teodoro, M. D.; Dorogan, V. G.; Benamara, M.; Wu, J.; Tarasov, G. G.; Marega, E.; Wang, Z. M.; Marques, G. E.; Salamo, G. J.

    2015-04-01

    The interplay between structural properties and charge transfer in self-assembled quantum ring (QR) chains grown by molecular beam epitaxy on top of an InGaAs/GaAs quantum dot (QD) superlattice template is analyzed and characterized. The QDs and QRs are vertically stacked and laterally coupled as well as aligned within each layer due to the strain field distributions that governs the ordering. The strong interdot coupling influences the carrier transfer both along as well as between chains in the ring layer and dot template structures. A qualitative contrast between different dynamic models has been developed. By combining temperature and excitation intensity effects, the tuning of the photoluminescence gain for either the QR or the QD mode is attained. The information obtained here about relaxation parameters, energy scheme, interlayer and interdot coupling resulting in creation of 1D structures is very important for the usage of such specific QR-QD systems for applied purposes such as lasing, detection, and energy-harvesting technology of future solar panels.

  17. Carrier transfer in vertically stacked quantum ring-quantum dot chains

    Energy Technology Data Exchange (ETDEWEB)

    Mazur, Yu. I., E-mail: ymazur@uark.edu; Dorogan, V. G.; Benamara, M.; Salamo, G. J. [Arkansas Institute for Nanoscale Materials Science and Engineering, University of Arkansas, Fayetteville, Arkansas 72701 (United States); Lopes-Oliveira, V.; Lopez-Richard, V.; Teodoro, M. D.; Marques, G. E. [Departamento de Fisica, Universidade Federal de São Carlos, 13565-905 São Carlos, São Paulo (Brazil); Souza, L. D. de [Departamento de Fisica, Universidade Federal de São Carlos, 13565-905 São Carlos, São Paulo (Brazil); Arkansas Institute for Nanoscale Materials Science and Engineering, University of Arkansas, Fayetteville, Arkansas 72701 (United States); Wu, J.; Wang, Z. M. [State Key Laboratory of Electronic Thin Film and Integrated Devices, University of Electronic Science and Technology of China, Chengdu (China); Tarasov, G. G. [Institute of Semiconductor Physics, National Academy of Sciences, pr. Nauki 45, Kiev 03028 (Ukraine); Marega, E. [Instituto de Fisica de São Carlos, Universidade de São Paulo, 13.566-590 São Carlos, São Paulo (Brazil)

    2015-04-21

    The interplay between structural properties and charge transfer in self-assembled quantum ring (QR) chains grown by molecular beam epitaxy on top of an InGaAs/GaAs quantum dot (QD) superlattice template is analyzed and characterized. The QDs and QRs are vertically stacked and laterally coupled as well as aligned within each layer due to the strain field distributions that governs the ordering. The strong interdot coupling influences the carrier transfer both along as well as between chains in the ring layer and dot template structures. A qualitative contrast between different dynamic models has been developed. By combining temperature and excitation intensity effects, the tuning of the photoluminescence gain for either the QR or the QD mode is attained. The information obtained here about relaxation parameters, energy scheme, interlayer and interdot coupling resulting in creation of 1D structures is very important for the usage of such specific QR–QD systems for applied purposes such as lasing, detection, and energy-harvesting technology of future solar panels.

  18. Evidence of three-level trophic transfer of quantum dots in an aquatic food chain by using bioimaging.

    Science.gov (United States)

    Lee, Woo-Mi; An, Youn-Joo

    2015-05-01

    In this study, we demonstrated the three-level trophic transfer of quantum dots (QDs) within the aquatic food chain. Using bioimaging, we observed QD transfer from protozoa (Astasia longa) to zooplankton (Moina macrocopa) to fish (Danio rerio). Bioimaging is an effective tool that can improve our understanding of the delivery of nanomaterials in vivo. Measurement with an intravital multiphoton laser scanning microscope visually proved the transfer of QDs from the first to the second and the second to the third levels. As QDs may be passed from lower organisms to humans via the food chain, our findings have implications for the safety of their use. PMID:25119416

  19. Impairment of Electron Transfer Chain Induced by Acute Carnosine Administration in Skeletal Muscle of Young Rats

    Directory of Open Access Journals (Sweden)

    José Roberto Macarini

    2014-01-01

    Full Text Available Serum carnosinase deficiency is an inherited disorder that leads to an accumulation of carnosine in the brain tissue, cerebrospinal fluid, skeletal muscle, and other tissues of affected patients. Considering that high levels of carnosine are associated with neurological dysfunction and that the pathophysiological mechanisms involved in serum carnosinase deficiency remain poorly understood, we investigated the in vivo effects of carnosine on bioenergetics parameters, namely, respiratory chain complexes (I–III, II, and II-III, malate dehydrogenase, succinate dehydrogenase, and creatine kinase activities and the expression of mitochondrial-specific transcription factors (NRF-1, PGC-1α, and TFAM in skeletal muscle of young Wistar rats. We observed a significant decrease of complexes I–III and II activities in animals receiving carnosine acutely, as compared to control group. However, no significant alterations in respiratory chain complexes, citric acid cycle enzymes, and creatine kinase activities were found between rats receiving carnosine chronically and control group animals. As compared to control group, mRNA levels of NRF-1, PGC-1α, and TFAM were unchanged. The present findings indicate that electron transfer through the respiratory chain is impaired in skeletal muscle of rats receiving carnosine acutely. In case these findings are confirmed by further studies and ATP depletion is also observed, impairment of bioenergetics could be considered a putative mechanism responsible for the muscle damage observed in serum carnosinase-deficient patients.

  20. Mechanisms involved in the selective transfer of long chain polyunsaturted fatty acids to the fetus

    Directory of Open Access Journals (Sweden)

    Alfonso eGil-Sánchez

    2011-09-01

    Full Text Available The concentration of long chain polyunsaturated fatty acid (LCPUFA in the fetal brain increases dramatically from the third trimester until 18 months of life. Several studies have shown an association between the percentage of maternal plasma docosahexaenoic acid (DHA during gestation and development of the cognitive functions in the neonate. Since only very low levels of LCPUFA are synthesized in the fetus and placenta, their primary source for the fetus is that of maternal origin. Both in vitro and human in vivo studies using labelled fatty acids have shown the preferential transfer of LCPUFA from the placenta to the fetus compared with other fatty acids, although the mechanisms involved are still uncertain. The placenta takes up circulating maternal non-esterified fatty acids (NEFA and fatty acids released mainly by maternal lipoprotein lipase and endothelial lipase. These NEFA may enter the cell by passive diffusion or by means of membrane carrier proteins. Once in the cytosol, NEFA bind to cytosolic fatty acid-binding proteins for transfer to the fetal circulation or can be oxidized within the trophoblasts and even re-esterified and stored in lipid droplets (LD. Although trophoblast cells are not specialized in lipid storage, LCPUFA may up-regulate peroxisome proliferator activated receptor-γ (PPARγ and hence the gene expression of fatty acid transport carriers, fatty acid acyl-CoA synthetases and adipophilin or other enzymes related with lipolysis, modifying their rate of placental transfer and metabolization. The placental transfer of LCPUFA during pregnancy seems to be a key factor in the neurological development of the fetus. Increased knowledge on the factors that modify placental transfer of fatty acids would contribute to our understanding of this complex process.

  1. Influence of dispersants on trophic transfer of petroleum hydrocarbons in a marine food chain

    Energy Technology Data Exchange (ETDEWEB)

    Wolfe, M.; Tjeerdema, R. [Univ. of California, Santa Cruz, CA (United States). Dept. of Chemistry and Biochemistry; Sowby, M. [California Dept. of Fish and Game, Sacramento, CA (United States)

    1995-12-31

    When crude oil is accidentally released into the ocean, it threatens many levels of marine life. Intervention, in the form of chemical dispersing agents, alters the normal behavior of petroleum hydrocarbons (PH) by increasing their functional water solubility and the extent of their exposure to sub-surface organisms. Dispersing agents may modify bioavailability as a result of altered interactions between dispersed PH droplets and organismal cell membranes.The objective of this research was to determine the impact of dispersing agents on PH bioavailability and trophic transfer in primary levels of a marine food chain. Uptake, bioaccumulation, depuration, and metabolic transformation of a model PH, {sup 14}C-naphthalene, were measured and compared for Prudhoe Bay Crude Oil (PBCO) dispersed with Corexit 9527 and undispersed preparations of the water-accommodated fractions (WAF) of PBCO at two salinities and temperatures. The model food chain consisted of Isochrysis galbana and Brachionus plicatilis. Direct aqueous exposure was compared with combined aqueous and dietary exposure. Fractionation and identification of metabolites was done by HPLC co-chromatography with analytical standards, and quantitation was done by liquid scintillation counting. GC-FID characterization of WAF and dispersed oil (DO) preparations shows higher concentrations of petroleum hydrocarbons and a greater number of individual constituents in the dispersed oil preparations.

  2. Transfer of selenium from prey to predators in a simulated terrestrial food chain

    International Nuclear Information System (INIS)

    Little is known about the accumulation and effects of selenium in reptiles. We developed a simplified laboratory food chain where we fed commercial feed laden with seleno-D,L-methionine (30 μg/g dry mass) to crickets (Acheta domestica) for 5-7 d. Se-enriched crickets (∼15 μg/g Se [dry mass]) were fed to juvenile male and female lizards (Sceloporus occidentalis) for 98 d while conspecifics were fed uncontaminated crickets. Lizards fed contaminated prey accumulated Se concentrations ranging from 9.3 (in female carcass) to 14.1 (in female gonad) μg/g compared to <1.5 μg/g in tissues of controls. Female gonad concentrations approached the highest of thresholds for reproductive toxicity in oviparous vertebrates. However, we observed no consistent effect of dietary treatment on sublethal parameters or survival. Our simplified food chain proved to be an ecologically relevant method of exposing lizards to Se, and forms the foundation for future studies on maternal transfer and teratogenicity of Se. - Partitioning of selenium among tissues differs between male and female lizards

  3. Evaluation of food chain transfer of the antibiotic oxytetracycline and human risk assessment.

    Science.gov (United States)

    Boonsaner, Maliwan; Hawker, Darryl W

    2013-10-01

    There has been recent concern regarding the possibility of antibiotics entering the aquatic food chain and impacting human consumers. This work reports experimental results of the bioconcentration of the antibiotic oxytetracycline (OTC) by the Asian watermeal plant (Wolffia globosa Hartog & Plas) and bioaccumulation of OTC in watermeal and water by the seven-striped carp (Probarbus jullieni). They show, for the first time, the extent to which OTC is able to transfer from water to plant to fish and enter the food chain. The mean bioconcentration factor (dry weight basis) with watermeal was 1.28 × 10(3) L kg(-1). Separate experiments were undertaken to characterize accumulation of OTC by carp from water and watermeal. These showed the latter pathway to be dominant under the conditions employed. The bioconcentration and biomagnification factors for these processes were 1.75 L kg(-1) and 2 × 10(-4) kg g(-1) respectively. Using an aqueous concentration range of 0.34-3.0 μg L(-1), hazard quotients for human consumption of contaminated fish of 1.3 × 10(-2) to 1.15 × 10(-1) were derived.

  4. Side chain effects in reactions of the potassium-tyrosine charge transfer complex

    Science.gov (United States)

    da Silva, F. Ferreira; Meneses, G.; Ingólfsson, O.; Limão-Vieira, P.

    2016-10-01

    Fragmentation of transient negative ions of tyrosine formed through electron transfer in collisions with neutral potassium atoms is presented in the collision energy range from 30 to 75 eV. At low collision energies the dominating side chain channel observed corresponds to the cleavage of the bond from the para-position of the phenyl ring to the β-C of the remaining moiety, but cleavage of the Cαsbnd Cβ bond is also observed. Further fragments are formed through cleavage of the Cα bond to the carbonyl group, through decomposition of the carboxyl group or through significant decomposition of the backbone. The dehydrogenated molecular anion is also observed with appreciable intensity. These results are discussed in the context of earlier studies on dissociative electron attachment to tyrosine and other amino acids, as well as within the role of the side chain in electron induced decomposition of this aromatic amino acid. Stabilization of the temporary molecular anion in the transient collision complex is discussed and we argue that this may have significant influence on the branching ratios observed.

  5. Bioaccumulative and conchological assessment of heavy metal transfer in a soil-plant-snail food chain

    Directory of Open Access Journals (Sweden)

    Nica Dragos V

    2012-06-01

    Full Text Available Abstract Background Copper (Cu, zinc (Zn, cadmium (Cd, and lead (Pb can pose serious threats to environmental health because they tend to bioaccumulate in terrestrial ecosystems. We investigated under field conditions the transfer of these heavy metals in a soil-plant-snail food chain in Banat area, Romania. The main goal of this paper was to assess the Roman snail (Helix pomatia usefulness in environmental monitoring as bioindicator of heavy metal accumulation. Eight sampling sites, selected by different history of heavy metal (HM exposure, were chosen to be sampled for soil, nettle leaves, and newly matured snails. This study also aimed to identify the putative effects of HM accumulation in the environment on phenotypic variability in selected shell features, which included shell height (SH, relative shell height (RSH, and whorl number (WN. Results Significantly higher amounts of HMs were accumulated in snail hepatopancreas and not in foot. Cu, Zn, and Cd have biomagnified in the snail body, particularly in the hepatopancreas. In contrast, Pb decreased when going up into the food chain. Zn, Cd, and Pb correlated highly with each other at all levels of the investigated food chain. Zn and Pb exhibited an effective soil–plant transfer, whereas in the snail body only foot Cu concentration was correlated with that in soil. There were significant differences among sampling sites for WN, SH, and RSH when compared with reference snails. WN was strongly correlated with Cd and Pb concentrations in nettle leaves but not with Cu and Zn. SH was independent of HM concentrations in soil, snail hepatopancreas, and foot. However, SH correlated negatively with nettle leaves concentrations for each HM except Cu. In contrast, RSH correlated significantly only with Pb concentration in hepatopancreas. Conclusions The snail hepatopancreas accumulates high amounts of HMs, and therefore, this organ can function as a reliable biomarker for tracking HM bioavailability

  6. Electrochemical studies of a reconstituted photosynthetic electron-transfer chain or towards a biomimetic photoproduction of hydrogen

    International Nuclear Information System (INIS)

    The aim of this work is to find an efficient process to convert solar energy into hydrogen. The electrons transfers in reconstituted photosynthetic chains have been particularly studied with the aims 1)in one hand, to better understand the interactions of the different molecules of the photosynthetic chain in order to optimize the changes of the entire organisms for hydrogen production 2)in another hand, to insert the hydrogenases in a photosynthetic chain and then to photo reduce them in order to obtain kinetic data to better understand how it works. (O.M.)

  7. Bond-length alternation and charge transfer in a linear carbon chain encapsulated within a single-walled carbon nanotube

    Science.gov (United States)

    Rusznyák, Á.; Zólyomi, V.; Kürti, J.; Yang, S.; Kertesz, M.

    2005-10-01

    The physical properties of a linear carbon chain encapsulated within single-walled carbon nanotubes are investigated with density-functional theory using periodic boundary conditions. The dominant feature of an isolated carbon chain is the Peierls dimerization and the opening of a Peierls gap. The two weakly interacting subsystems (infinite carbon chain and nanotube) establish a common Fermi level, resulting in charge transfer (CT) which leads to a metallic combined system with a high density of states at the Fermi level. The rigid band model provides useful insights. Unusual physics arises from the effects of CT and chain-tube orbital hybridization which both tend to suppress the Peierls dimerization. Implications for the observed Raman spectrum of the chain-nanotube system are discussed.

  8. Identification and evaluation of modularization practices in an automotive supplier: progressivity analysis of transferring activities in the supply chain

    Directory of Open Access Journals (Sweden)

    Evandro Prieto

    2013-08-01

    Full Text Available The automotive value chain has more and more been making room to a strategy of which activities of product design and production have been transferred to the module suppliers. The transfer of value-added activities occurs from assembler to the module suppliers. The former assume the role of integrators within the supply chain. The supply chain participants have started to strengths their competencies in order to obtain advantages in the economy of scale and scope. In this context, the present work aims at investigating the valued-added transfer between first and second tiers of automotive supply chain in new product development and production. The work was carried out from an evaluation of a supplier with regard to modularization. The theoretical background considers the concepts of integrated and modular architecture as well as the progressiveness of competencies among suppliers. It adopts single cased as the research methodological approach. The literature points out that the process of modularization either in product development or in production offer benefits for both sides: assemblers and suppliers. The results from the investigated supplier shows inherent benefits due to the acquisition of new technologies that enable an increase of technical and management learning in projects of new products. Therefore, it demonstrates that in this modularity environment, the potential of value-added transfer is associated to the level of progressiveness of competencies that are incorporated to deliver module solutions to assemblers; the investigated supplier can be categorized in an “embrionary” stage.

  9. Some observations on plutonium transfers in human and animal food-chains and Gi tract: plutonium complexation parameters

    International Nuclear Information System (INIS)

    Although many data have been accumulated concerning the distribution of Pu in waters, soils, and foodchains, recent studies have raised the question of the Pu physico-chemical species and their differential availability. Accordingly, we reviewed published data on the transfer of Pu in foodchains and in the gastrointestinal tracts. Dietetic, physico-chemical, biochemical and microbiological parameters have been studied and their incidence on the intestinal transfer factor f1 of Pu in man briefly discussed: the transfer in the trophic chains often increases Pu mobility and perhaps f1. Experimental research is needed to obtain quantitative data

  10. Transfer of Paralytic Shellfish Toxins via Marine Food Chains:A Simulated Experiment

    Institute of Scientific and Technical Information of China (English)

    ZHI-JUN TAN; TIAN YAN; PEN-CHENG YU; MING-JIANG ZHOU

    2007-01-01

    Objective To study the transfer of paralytic shellfish toxins(PST)using four simulated marine food chains:d8noflagellate Alexandrium tamarense→Artemia Anemia salina→Mysid shrimp Neomysis awatschensis;A.tamarense→N.awatschensis:A.tamarense→A.salina→Perch Lateolabrax japonicus;and A.tamarenae→L. japonicus. Methods The ingestion of A.tamarenge.a producer of PST, by L. japonicus,N.awatschensis,and A.salina was first confirmed by microscopic observation of A.tamarense cells in the intestine samples of the three different organisms,and by the analysis of Chl.a levels in the samples.Toxin accumulation in L.japonicus and N.awatschensis directly from the feeding on A.tamarense 8r indirectly through the vector of A.salina was then studied.The toxicity of samples was measured using the AOAC mouse bioassay method,and the toxin content and profile of A.tamarense were analyzed by the HPLC method.Results Both A.salina and N.nwatschensis could ingest A.tamarense cells.However,the ingestion capability of A.salina exceeded that of N.L. japonicus.N.awatschensis and A.salina by microscopic observation.Therefore,the three organisms could ingest A.tamarense cells directly.A.salina could accumulate high content of PST,and the toxicity of A.salina in samples collected on of tested mice within 7 minutes,and the toxin content in artemia sample collected on the lst day was estimated to be 1.65×10-5 μg STX equal/individual.Toxin accumulation in L.japonicus and N.awatschensis directly from the feeding on A.tamarense or indirectly from the vector of A.salina was also studied.The mice injected with extracts from L.japonicus and N. awatschensis samples that accumulated PST either directly or indirectly showed PST intoxication symptoms,indicating that low levels of PST existed in these samples Conclusion Paralytic shellfish toxins can be transferred to L.japonicus,N.awatschensis,and A.salina from A.tamarense directly or indirectly via the food chains.

  11. Markov chain formalism for generalized radiative transfer in a plane-parallel medium, accounting for polarization

    Science.gov (United States)

    Xu, Feng; Davis, Anthony B.; Diner, David J.

    2016-11-01

    A Markov chain formalism is developed for computing the transport of polarized radiation according to Generalized Radiative Transfer (GRT) theory, which was developed recently to account for unresolved random fluctuations of scattering particle density and can also be applied to unresolved spectral variability of gaseous absorption as an improvement over the standard correlated-k method. Using Gamma distribution to describe the probability density function of the extinction or absorption coefficient, a shape parameter a that quantifies the variability is introduced, defined as the mean extinction or absorption coefficient squared divided by its variance. It controls the decay rate of a power-law transmission that replaces the usual exponential Beer-Lambert-Bouguer law. Exponential transmission, hence classic RT, is recovered when a→∞. The new approach is verified to high accuracy against numerical benchmark results obtained with a custom Monte Carlo method. For a<∞, angular reciprocity is violated to a degree that increases with the spatial variability, as observed for finite portions of real-world cloudy scenes. While the degree of linear polarization in liquid water cloudbows, supernumerary bows, and glories is affected by spatial heterogeneity, the positions in scattering angle of these features are relatively unchanged. As a result, a single-scattering model based on the assumption of subpixel homogeneity can still be used to derive droplet size distributions from polarimetric measurements of extended stratocumulus clouds.

  12. Origin of the red sites and energy transfer rates in single MEH-PPV chains at low temperature.

    Science.gov (United States)

    Feist, Florian A; Zickler, Martin F; Basché, Thomas

    2011-06-01

    Single poly[2-methoxy-5-(2'-ethyl-hexyloxy)-1,4-phenylene vinylene] (MEH-PPV) molecules dispersed in thin poly(methylmethacrylate) films have been investigated by fluorescence emission, excitation and time-resolved spectroscopy at 1.2 K. For the molecular weight studied (∼200 kDa) a bimodal distribution of emission maxima is observed. Based on a comparison of the spectroscopic properties of blue and red sites and on polarisation-resolved measurements, we argue in agreement with recent quantum-chemical calculations that the red subpopulation most probably does not arise from interchromophoric excitation delocalisation but is to be attributed to longer chromophoric units originating from ordered regions of a polymer chain, where due to constraints on the chain conformation larger conjugation lengths can be realised. In excitation spectra within the red spectral region we can identify multiple chromophoric units, among them chromophores without correspondence in the emission spectrum-donors of the intramolecular energy transfer. Zero-phonon lines of donor chromophores proved to be significantly broadened, indicating fast excited-state population decay due to energy transfer. Thus, a distribution of energy transfer times within MEH-PPV chains could be determined from donor zero-phonon line widths, with an average value of 3.9 ps. Our study represents the first direct measurement of energy transfer times in conjugated polymers, parameters that are crucial for the performance of many technical applications based on this class of material. PMID:21472962

  13. Transfer of mercury and methylmercury along macroinvertebrate food chains in a floodplain lake of the Beni River, Bolivian Amazonia

    Energy Technology Data Exchange (ETDEWEB)

    Molina, Carlos Israel, E-mail: camoar6088@gmail.com [Instituto de Ecologia, Unidad de Limnologia, UMSA, Casilla postal 10077, La Paz (Bolivia, Plurinational State of); Institut de Recherche pour le Developpement IRD, Casilla postal 9214, La Paz (Bolivia, Plurinational State of); CONICET-Facultad de Ciencias Naturales, Universidad Nacional de Tucuman, Miguel Lillo 205, 4 000, Tucuman (Argentina); Gibon, Francois-Marie [Institut de Recherche pour le Developpement IRD, Casilla postal 9214, La Paz (Bolivia, Plurinational State of); IRD, UMR BOREA, Museum national d' Histoire Naturelle MNHN, Case postale 26, 75231, Paris cedex 05 (France); Duprey, Jean-Louis [Institut de Recherche pour le Developpement IRD, Casilla postal 9214, La Paz (Bolivia, Plurinational State of); Dominguez, Eduardo [CONICET-Facultad de Ciencias Naturales, Universidad Nacional de Tucuman, Miguel Lillo 205, 4 000, Tucuman (Argentina); Guimaraes, Jean-Remy D. [Instituto de Biofisica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Bloco G-CCS, Rio de Janeiro, CEP 21949-900 (Brazil); Roulet, Marc [Institut de Recherche pour le Developpement IRD, Casilla postal 9214, La Paz (Bolivia, Plurinational State of)

    2010-07-15

    We have evaluated the mercury and methylmercury transfers to and within the macroinvertebrate communities of a floodplain lake of the Beni River basin, Bolivia, during three hydrological seasons and in two habitats (open water and vegetation belt). Using the stable isotopes {delta}{sup 13}C and {delta}{sup 15}N, six trophic chains were identified during a previous study. Four are based on only one source: seston, organic matter from the bottom sediment, periphyton and macrophytes. Two are based on mixed sources (seston and periphyton in one case, periphyton and macrophytes in the other). During sampling, we found only one taxon that had surface sediment organic matter as food source and very few taxa whose trophic source was constituted by macrophytes. The periphyton was the most important source during all seasons; it produced the longest chain, with three trophic positions. Whatever the season and trophic source, all collected macroinvertebrates contained methyl mercury and the latter was biomagnified in all trophic chains that we identified. The biomagnification of methylmercury through invertebrate trophic chains accurately reflected the existence and length of these chains. Biomagnification was virtually non-existent in the sediment-based chain, low and restricted to the dry season in the macrophyte-based chain. It was significant in the seston-based chain, but limited by the existence of only two trophic levels and restricted to the wet season. Finally, it was very effective in the periphyton-based chain, which offers the highest rate of contamination of the source but, above all, the largest number of trophic levels.

  14. Surface modification of carbon nanotubes via combination of mussel inspired chemistry and chain transfer free radical polymerization

    International Nuclear Information System (INIS)

    Graphical abstract: A novel strategy combination of mussel inspired chemistry and chain transfer free radical polymerization has been developed for surface modification of carbon nanotubes with polymers for the first time. - Highlights: • Surface modification of CNTs via mussel inspired chemistry. • Preparation of aminated polymers through free radical polymerization. • Functionalized CNTs with aminated polymers via Michael addition reaction. • Highly dispersed CNTs in organic and aqueous solution. - Abstract: In this work, a novel strategy for surface modification of carbon nanotubes (CNTs) was developed via combination of mussel inspired chemistry and chain transfer free radical polymerization. First, pristine CNTs were functionalized with polydopamine (PDA), which is formed via self-polymerization of dopamine in alkaline conditions. These PDA functionalized CNTs can be further reacted with amino-terminated polymers (named as PDMC), which was synthesized through chain transfer free radical polymerization using cysteamine hydrochloride as chain transfer agent and methacryloxyethyltrimethyl ammonium chloride as the monomer. PDMC perfectly conjugated with CNT-PDA was ascertained by a series of characterization techniques including transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), thermal gravimetric analysis (TGA) and X-ray photoelectron spectroscopy (XPS). The dispersibility of obtained CNT nanocomposites (named as CNT-PDA-PDMC) was further examined. Results showed that the dispersibility of CNT-PDA-PDMC in aqueous and organic solutions was obviously enhanced. Apart from PDMC, many other amino-terminated polymers can also be used to functionalization of CNTs via similar strategy. Therefore, the method described in this work should be a general strategy for fabrication various polymer nanocomposites

  15. Surface modification of carbon nanotubes via combination of mussel inspired chemistry and chain transfer free radical polymerization

    Energy Technology Data Exchange (ETDEWEB)

    Wan, Qing; Tian, Jianwen; Liu, Meiying; Zeng, Guangjian; Huang, Qiang [Department of Chemistry, Nanchang University, 999 Xuefu Avenue, Nanchang, 330031 (China); Wang, Ke; Zhang, Qingsong [Department of Chemistry and the Tsinghua Center for Frontier Polymer Research, Tsinghua University, Beijing, 100084 (China); Deng, Fengjie, E-mail: fengjiedeng@aliyun.com [Department of Chemistry, Nanchang University, 999 Xuefu Avenue, Nanchang, 330031 (China); Zhang, Xiaoyong, E-mail: xiaoyongzhang1980@gmail.com [Department of Chemistry, Nanchang University, 999 Xuefu Avenue, Nanchang, 330031 (China); Wei, Yen, E-mail: weiyen@tsinghua.edu.cn [Department of Chemistry and the Tsinghua Center for Frontier Polymer Research, Tsinghua University, Beijing, 100084 (China)

    2015-08-15

    Graphical abstract: A novel strategy combination of mussel inspired chemistry and chain transfer free radical polymerization has been developed for surface modification of carbon nanotubes with polymers for the first time. - Highlights: • Surface modification of CNTs via mussel inspired chemistry. • Preparation of aminated polymers through free radical polymerization. • Functionalized CNTs with aminated polymers via Michael addition reaction. • Highly dispersed CNTs in organic and aqueous solution. - Abstract: In this work, a novel strategy for surface modification of carbon nanotubes (CNTs) was developed via combination of mussel inspired chemistry and chain transfer free radical polymerization. First, pristine CNTs were functionalized with polydopamine (PDA), which is formed via self-polymerization of dopamine in alkaline conditions. These PDA functionalized CNTs can be further reacted with amino-terminated polymers (named as PDMC), which was synthesized through chain transfer free radical polymerization using cysteamine hydrochloride as chain transfer agent and methacryloxyethyltrimethyl ammonium chloride as the monomer. PDMC perfectly conjugated with CNT-PDA was ascertained by a series of characterization techniques including transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), thermal gravimetric analysis (TGA) and X-ray photoelectron spectroscopy (XPS). The dispersibility of obtained CNT nanocomposites (named as CNT-PDA-PDMC) was further examined. Results showed that the dispersibility of CNT-PDA-PDMC in aqueous and organic solutions was obviously enhanced. Apart from PDMC, many other amino-terminated polymers can also be used to functionalization of CNTs via similar strategy. Therefore, the method described in this work should be a general strategy for fabrication various polymer nanocomposites.

  16. Lysophosphatidylcholine as an adjuvant for lentiviral vector mediated gene transfer to airway epithelium: effect of acyl chain length

    Directory of Open Access Journals (Sweden)

    Anson Don S

    2010-06-01

    Full Text Available Abstract Background Poor gene transfer efficiency has been a major problem in developing an effective gene therapy for cystic fibrosis (CF airway disease. Lysophosphatidylcholine (LPC, a natural airway surfactant, can enhance viral gene transfer in animal models. We examined the electrophysiological and physical effect of airway pre-treatment with variants of LPC on lentiviral (LV vector gene transfer efficiency in murine nasal airways in vivo. Methods Gene transfer was assessed after 1 week following nasal instillations of a VSV-G pseudotype LV vector pre-treated with a low and high dose of LPC variants. The electrophysiological effects of a range of LPC variants were assessed by nasal transepithelial potential difference measurements (TPD to determine tight junction permeability. Any physical changes to the epithelium from administration of the LPC variants were noted by histological methods in airway tissue harvested after 1 hour. Results Gene transduction was significantly greater compared to control (PBS for our standard LPC (palmitoyl/stearoyl mixture treatment and for the majority of the other LPC variants with longer acyl chain lengths. The LPC variant heptadecanoyl also produced significantly greater LV gene transfer compared to our standard LPC mixture. LV gene transfer and the transepithelial depolarization produced by the 0.1% LPC variants at 1 hour were strongly correlated (r2 = 0.94, but at the 1% concentration the correlation was less strong (r2 = 0.59. LPC variants that displayed minor to moderate levels of disruption to the airway epithelium were clearly associated with higher LV gene transfer. Conclusions These findings show the LPC variants effect on airway barrier function and their correlation to the effectiveness of gene expression. The enhanced expression produced by a number of LPC variants should provide new options for preclinical development of efficient airway gene transfer techniques.

  17. Terrestrial model food chain and environmental chemicals. I. Transfer of sodium (/sup 14/C)pentachlorophenate between springtails and carabids

    Energy Technology Data Exchange (ETDEWEB)

    Gruttke, H.; Kratz, W.; Weigmann, G.; Haque, A.

    1988-06-01

    A model soil food chain of a ruderal ecosystem has been constructed in order to study the uptake, transfer, and accumulation of (/sup 14/C)pentachlorophenate (PCP-Na). The model was based on three food levels, viz. baker's yeast, collembola, and carabid beetles, and the contaminant chemical introduced was via initial food. Continuous exposure of the organisms to the test chemical resulted in a significant uptake and transfer of radiocarbon into the food chain elements. Bioaccumulation of radiocarbon in the body tissues of the organisms was low, as large amounts taken up were quickly eliminated through the excrements. The radiocarbon level of prey animals was about 100 times higher than that of their predators, but there was only small difference in concentration between collembolas and yeast. This was probably because of a faster excretion of the chemical by the beetles than by the collembolas. During the test period no conversion of (/sup 14/C)PCP-Na took place in the yeast, but the collembolas and beetles metabolized 50 and 59%, respectively. Criteria are proposed for successful implementation of food chain models.

  18. Terrestrial model food chain and environmental chemicals. I. Transfer of sodium [14C]pentachlorophenate between springtails and carabids

    International Nuclear Information System (INIS)

    A model soil food chain of a ruderal ecosystem has been constructed in order to study the uptake, transfer, and accumulation of [14C]pentachlorophenate (PCP-Na). The model was based on three food levels, viz. baker's yeast, collembola, and carabid beetles, and the contaminant chemical introduced was via initial food. Continuous exposure of the organisms to the test chemical resulted in a significant uptake and transfer of radiocarbon into the food chain elements. Bioaccumulation of radiocarbon in the body tissues of the organisms was low, as large amounts taken up were quickly eliminated through the excrements. The radiocarbon level of prey animals was about 100 times higher than that of their predators, but there was only small difference in concentration between collembolas and yeast. This was probably because of a faster excretion of the chemical by the beetles than by the collembolas. During the test period no conversion of [14C]PCP-Na took place in the yeast, but the collembolas and beetles metabolized 50 and 59%, respectively. Criteria are proposed for successful implementation of food chain models

  19. Radiation and environment. Study of uranium transfer to humans by the food chain: experiment design and first results

    International Nuclear Information System (INIS)

    During years, scientific assessments had considered plants, animal and other living organism as part of the environment in which radionuclides become dispersed. They were further seen as resources which, when contaminated, may contribute to human radiation exposure since some plants and animals are elements of food chains and represent pathways for the transfer of radionuclides to humans. Today, the assessments are development reflected the generally accepted position that priority should be given to evaluating the potential consequences for humans, which are among the most radiosensitive mammalian species. The transfer of radioisotopes from food to humans is still a well debated issue, because experimental results are even scarce. As a contribution to this issue, the Linear Accelerator Laboratory of the Physics Institute at the Sao Paulo University jointed to other institute of Brazil and Cuba development a project for study of uranium in the food-chain: food-animal/vegetables-human. This project involves experimentation with mammalians (wistar rats and beagles dogs), fishes and vegetables, plus extrapolation to humans by means of the General Multiple-Compartments Model. The pilot experiments in animal and vegetables are well described in the paper. As first results were obtained the transfer coefficients of uranium to the organs of animals as a function of the uranium concentration present in the administered food and the transfer coefficients of uranium for each part of the plant, as function of both growing time and uranium concentration in the nutrients solution. With this data it would be possible to evaluate the uranium ingestion by humans from animal products and plants, given their dietary habits, to infer human absorption of uranium associated with prolonged intake of uranium contained in food and estimates the content of uranium transferred to humans organs, thus allowing the evaluation of internally localized doses and the radiobiological damage and

  20. Elucidation and Control of an Intramolecular Charge Transfer Property of Fucoxanthin by a Modification of Its Polyene Chain Length.

    Science.gov (United States)

    Kosumi, Daisuke; Kajikawa, Takayuki; Okumura, Satoshi; Sugisaki, Mitsuru; Sakaguchi, Kazuhiko; Katsumura, Shigeo; Hashimoto, Hideki

    2014-03-01

    Fucoxanthin is an essential pigment for the highly efficient light-harvesting function of marine algal photosynthesis. It exhibits excited state properties attributed to intramolecular charge transfer (ICT) in polar environments due to the presence of the carbonyl group in its polyene backbone. This report describes the excited state properties of fucoxanthin homologues with four to eight conjugated double bonds in various solvents using the femtosecond pump-probe technique. The results clarified that fucoxanthin homologues with longer polyene chains did not possess pronounced ICT spectroscopic signatures, while the shorter fucoxanthin homologues had a strong ICT character, even in a nonpolar solvent. On the basis of the observations, we quantitatively correlated the ICT character in the excited state to the conjugated polyene chain lengths of fucoxanthin molecules. PMID:26274069

  1. Leading coordinate analysis of reaction pathways in proton chain transfer: Application to a two-proton transfer model for the green fluorescent protein

    International Nuclear Information System (INIS)

    The 'leading coordinate' approach to computing an approximate reaction pathway, with subsequent determination of the true minimum energy profile, is applied to a two-proton chain transfer model based on the chromophore and its surrounding moieties within the green fluorescent protein (GFP). Using an ab initio quantum chemical method, a number of different relaxed energy profiles are found for several plausible guesses at leading coordinates. The results obtained for different trial leading coordinates are rationalized through the calculation of a two-dimensional relaxed potential energy surface (PES) for the system. Analysis of the 2-D relaxed PES reveals that two of the trial pathways are entirely spurious, while two others contain useful information and can be used to furnish starting points for successful saddle-point searches. Implications for selection of trial leading coordinates in this class of proton chain transfer reactions are discussed, and a simple diagnostic function is proposed for revealing whether or not a relaxed pathway based on a trial leading coordinate is likely to furnish useful information

  2. Developing a Taxonomy and Model to Transfer and Assess Best Practices for Supply Chain Management

    Science.gov (United States)

    Flores, Myrna; Mendoza, Ana; Lavin, Victor; Flores, Benito

    Supply Chain Management can be briefly defined as the orchestration of a network of entities such as suppliers, distributors and clients to achieve a common goal: delivering cost efficient products and services exceeding customers’ expectations. Therefore, firms should consider all those End-to-End processes enabling an efficient integration and interoperability of partners collaborating in such Supply Chain when designing their Business Process Architecture (BPA). One key enabler to accomplish this goal is the identification, documentation and sharing of best practices. This paper describes the outcomes of a collaborative project carried out by CEMEX Research Group and the Universidad de Monterrey (UDEM), which focused on developing taxonomy to document best practices for the supply chain management together with a generic model to evaluate their level of implementation.

  3. The transfer of titanium dioxide nanoparticles from the host plant to butterfly larvae through a food chain

    OpenAIRE

    Miyoko Kubo-Irie; Masaaki Yokoyama; Yusuke Shinkai; Rikio Niki; Ken Takeda; Masaru Irie

    2016-01-01

    This study aimed to examine the transfer of nanoparticles within a terrestrial food chain. Oviposited eggs of the swallowtail butterfly (Atrophaneura alcinous) were hatched on the leaves of the host plant (Aristolochia debilis), and the root stock and root hairs were submerged in a suspension of 10 μg/ml titanium dioxide nanoparticles (TiO2-NPs) in a 100 ml bottle. The presence of TiO2-NPs in the veins of the leaves was confirmed by X-ray analytical microscopy (X-ray AM). The hatched 1st inst...

  4. Transfer and effects of 1,2,3,5,7-pentachloronaphthalene in an experimental food chain

    DEFF Research Database (Denmark)

    Slootweg, Tineke; Segner, Helmut; Mayer, Philipp;

    2015-01-01

    of this study was to gain insights into the biomagnification and effects of 1,2,3,5,7-pentachloronaphthalene (PeCN52) in an experimental food chain consisting of benthic worms and juvenile rainbow trout. Worms were contaminated with PeCN52 by passive dosing from polydimethylsiloxane silicone. The contaminated...

  5. Enhancing Chinese Agribusiness Supply Chains with Internet Technologies: A Transnational Knowledge Transfer Approach

    Science.gov (United States)

    Duan, Yanqing; Bentley, Yongmei; Fu, Zetian; Zografos, Konstantinos; Bemeleit, Boris

    2008-01-01

    This paper reports research findings from a project funded by the European Commission. The research used case studies and surveys to identify gaps between Europe and China in the level of Internet adoption in fresh-produce supply chains. The project reveals barriers to Internet adoption in China in this industry, and employs a transnational…

  6. Evaluation of data on the transfer of radionuclides in the food chain post-Chernobyl action

    International Nuclear Information System (INIS)

    During the accident at Chernobyl large amounts of radioactive materials were released into the atmosphere and distributed all over Europe. Depending on the trajectories of the radioactive clouds and the large variation of rainfall during its passage through, large local and regional differences in deposition were observed, leading to an enhanced contamination of soil and plants. Consequently, the radionuclides entered the foodchain by several pathways. The radiological consequences of radionuclides discharged from nuclear installations usually are evaluated using doses assessment models. In these models the passage from one compartment into another, e.g. the transfer from soil into plants, from plants into milk or meat is defined by transfer factors, which are influenced by various parameters. From the long term point of view only the long-lived nuclides like 134/137Cs are important for long term radiation risk assessment after the Chernobyl accident. In this accident the release of radioactive materials took place over a longer time period and varied in rate and radionuclide composition. Some regions of Europe were contaminated several times. To improve radiation dose prediction the CEC has initiated the Post-Chernobyl radiation protection programme 'Evaluation of Data on the Transfer of Radionuclides in the Foodchain' including five main items to be studied by different laboratories: 1. Impact of chemical speciation on the radionuclide transfer in terrestrial ecosystems after a core disruptive accident, especially in soils and plants. 2. Transfer paths of radionuclides in seminatural and natural ecosystems and their role in contaminating the foodchain. 3. Validation of soil-to-plant parameters. 4. Transfer of radionuclides to animals and animal products. 5. Transfer paths in aquatic systems and their importance for the contamination of the foodchain

  7. SYNTHESIS OF HETEROARM STAR-SHAPED POLYMER BY THE USE OF POLYFUNCTIONAL CHAIN-TRANSFER AGENT via CONVENTIONAL FREE RADICAL POLYMERIZATION

    Institute of Scientific and Technical Information of China (English)

    Zhi-hua Luo; Zhi-feng Fu; Yan Shi

    2008-01-01

    Heteroarm star-shaped polymers were synthesized by conventional free radical polymerization in two steps by the use of polyfunctional chain transfer agent. In the first step, free radical polymerization of methyl methacrylate was carried out in the presence of a polyfunctional chain transfer agent, pentaerythritol tetrakis(3-mercaptopropinate). At appropriate monomer conversions, two-arm PMMA having two residual thiol groups at the chain center or three-arm PMMA having one residual thiol group at the core were obtained. In the second step, free radical polymerization of styrene was carried out using PMMAs obtained above as macro-chain transfer agent. When styrene conversion was lower than 30%, heteroarm star-shaped polymers, (PMMA)2(PS)a and (PMMA)3(PS), were obtained successfully.

  8. Plasmonics: Electromagnetic energy transfer and switching in nanoparticle chain-arrays below the diffraction limit

    Science.gov (United States)

    Brongersma, Mark; Hartman, John; Atwater, Harry

    2000-03-01

    Integrated optics faces the fundamental limitation that, for the guiding, modulation, and amplification of light, structures are needed that have dimensions comparable to the wavelength of light. Recently, it was theoretically shown that this problem can be circumvented by transporting electromagnetic energy along linear chains of closely spaced metal nanoparticles. This transport relies on the near-field electrodynamic interaction between metal particles that sets up coupled plasmon modes. We have modeled the transport properties of corners, T's, and switches that consist of chains of metal nanoparticles. It is shown that propagation is coherent and the group velocities can exceed saturated velocities of electrons in semiconductors ( ~ 105 m/s). High efficiency transmission of energy around sharp corners (bending radius plasmon mode. Finally, the operation of a plasmon switch is modeled in which plasmon waves can be switched. Suggestions are given for the choice of metal particle and host material. These "plasmonic devices" potentially are among the smallest structures with optical functionality.

  9. Uranium transfer in the food chain from soil to plants, animals and man

    International Nuclear Information System (INIS)

    Our investigations aimed at following up the scientific basis of uranium transfer from the soils of different geological origins and from the immediate vicinity of uranium waste dumps in the vegetation, in waters (drinking water, mineral water and medicinal water), vegetable and animal foodstuffs and beverages; the regional human uranium intake, excretion, apparent absorption and balance in Germany and Mexico. Another aim of the investigations was to draw conclusions from the rules of transfer of this element from the rocks and soils to plants, animals and man. (authors)

  10. Impairment of Electron Transfer Chain Induced by Acute Carnosine Administration in Skeletal Muscle of Young Rats

    OpenAIRE

    José Roberto Macarini; Soliany Grassi Maravai; José Henrique Cararo; Nádia Webber Dimer; Cinara Ludvig Gonçalves; Luiza Wilges Kist; Mauricio Reis Bogo; Patrícia Fernanda Schuck; Emilio Luiz Streck; Gustavo Costa Ferreira

    2014-01-01

    Serum carnosinase deficiency is an inherited disorder that leads to an accumulation of carnosine in the brain tissue, cerebrospinal fluid, skeletal muscle, and other tissues of affected patients. Considering that high levels of carnosine are associated with neurological dysfunction and that the pathophysiological mechanisms involved in serum carnosinase deficiency remain poorly understood, we investigated the in vivo effects of carnosine on bioenergetics parameters, namely, respiratory chain ...

  11. Arsenic Contamination in Food-chain: Transfer of Arsenic into Food Materials through Groundwater Irrigation

    OpenAIRE

    Huq, S.M. Imamul; Joardar, J.C.; Parvin, S.; Correll, Ray; Naidu, Ravi

    2006-01-01

    Arsenic contamination in groundwater in Bangladesh has become an additional concern vis-à-vis its use for irrigation purposes. Even if arsenic-safe drinking-water is assured, the question of irrigating soils with arsenic-laden groundwater will continue for years to come. Immediate attention should be given to assess the possibility of accumulating arsenic in soils through irrigation-water and its subsequent entry into the food-chain through various food crops and fodders. With this possibilit...

  12. Transfer of radionuclides from high polluted bottom sediments to marine organisms through benthic food chain in post Fukushima period

    Science.gov (United States)

    Bezhenar, Roman; Jung, Kyung Tae; Maderich, Vladimir; Willemsen, Stefan; de With, Govert; Qiao, Fangli

    2015-04-01

    A catastrophic earthquake and tsunami occurred on March 11, 2011 and severely damaged the Fukushima Daiichi Nuclear Power Plant (FDNPP) that resulted in an uncontrolled release of radioactivity into air and ocean. Around 80% of the radioactivity released due to the FDNPP accident in March-April 2011 was either directly discharged into the ocean or deposited onto the ocean surface from the atmosphere. A large amount of long-lived radionuclides (mainly Cs-137) were released into the environment. The concentration of radionuclides in the ocean reached a maximum in mid-April of 2011, and then gradually decreased. From 2011 the concentration of Cs-137 in water essentially fell except the area around the FDNPP where leaks of contaminated water are continued. However, in the bottom sediment high concentrations of Cs-137 were found in the first months after the accident and slowly decreased with time. Therefore, it should be expected that a time delay is found of sediment-bound radionuclides in marine organisms. For the modeling of radionuclide transfer from highly polluted bottom sediments to marine organisms the dynamical food chain model BURN-POSEIDON (Heling et al, 2002; Maderich et al., 2014) was extended. In this model marine organisms are grouped into a limited number of classes based on their trophic level and type of species. These include: phytoplankton, zooplankton, fishes (two types: piscivorous and non-piscivorous), crustaceans, and molluscs for pelagic food chain and bottom sediment invertebrates, demersal fishes and bottom predators for benthic food chain and whole water column predators feeding by pelagial and benthic fishes. Bottom invertebrates consume organic parts of bottom sediments with adsorbed radionuclides which then migrate through the food chain. All organisms take radionuclides directly from water as well as via food. In fishes where radioactivity is not homogeneously distributed over all tissues of the organism, it is assumed that radionuclide

  13. Characterization and Diagnostic Value of Amino Acid Side Chain Neutral Losses Following Electron-Transfer Dissociation

    Science.gov (United States)

    Xia, Qiangwei; Lee, M. Violet; Rose, Christopher M.; Marsh, Alyce J.; Hubler, Shane L.; Wenger, Craig D.; Coon, Joshua J.

    2011-02-01

    Using a large set of high mass accuracy and resolution ETD tandem mass spectra, we characterized ETD-induced neutral losses. From these data we deduced the chemical formula for 20 of these losses. Many of them have been previously observed in electron-capture dissociation (ECD) spectra, such as losses of the side chains of arginine, aspartic acid, glutamic acid, glutamine, asparagine, leucine, histidine, and carbamidomethylated cysteine residues. With this information, we examined the diagnostic value of these amino acid-specific losses. Among 1285 peptide-spectrum matches, 92.5% have agreement between neutral loss-derived peptide amino acid composition and the peptide sequences. Moreover, we show that peptides can be uniquely identified by using only the accurate precursor mass and amino acid composition based on neutral losses; the median number of sequence candidates from an accurate mass query is reduced from 21 to 8 by adding side chain loss information. Besides increasing confidence in peptide identification, our findings suggest the potential use of these diagnostic losses in ETD spectra to improve false discovery rate estimation and to enhance the performance of scoring functions in database search algorithms.

  14. Ethylene homo- and copolymerization chain-transfers: A perspective from supported (nBuCp)2ZrCl2 catalyst active centre distribution

    Indian Academy of Sciences (India)

    Muhammad Atiqullah; Mamdouh A Al-Harthi; Siripon Anantawaraskul; Abdul-hamid M Emwas

    2015-04-01

    Polymerization chain termination reactions and unsaturation of the polymer backbone end are related. Therefore, in this study, the parameters resulting from the modelling of the active centre distribution of the supported catalyst—silica/MAO/(nBuCp)2ZrCl2—were applied to evaluate the active-centredependent ethylene homo- and copolymerization rates, as well as the corresponding chain termination rates. This approach, from a microkinetic mechanistic viewpoint, elucidates better the 1-hexene-induced positive comonomer effect and chain transfer phenomenon. The kinetic expressions, developed on the basis of the proposed polymerization mechanisms, illustrate how the active site type-dependent chain transfer phenomenon is influenced by the different apparent termination rate constants and momoner concentrations. The active centrespecific molecular weight Mni (for the above homo- and copolymer), as a function of chain transfer probability, pCTi, varied as follows: log(pCTi) = log(mwru)−log(Mni) where mwru is the molecular weight of the repeat unit. The physical significance of this finding has been explained. The homo- and copolymer backbones showed all the three chain end unsaturations (vinyl, vinylidene, and trans-vinylene). The postulated polymerization mechanisms reveal the underlying polymer chemistry. The results of the present study will contribute to develop in future supported metallocene catalysts that will be useful to synthesize polyethylene precursors having varying chain end unsaturations, which can be eventually used to prepare functional polyethylenes.

  15. Electrochemical studies of a reconstituted photosynthetic electron-transfer chain or towards a biomimetic photoproduction of hydrogen; Etudes electrochimiques de chaines de transfert d'electrons photosynthetiques ou vers une photoproduction biomimetique d'hydrogene

    Energy Technology Data Exchange (ETDEWEB)

    Fourmond, V

    2007-04-15

    The aim of this work is to find an efficient process to convert solar energy into hydrogen. The electrons transfers in reconstituted photosynthetic chains have been particularly studied with the aims 1)in one hand, to better understand the interactions of the different molecules of the photosynthetic chain in order to optimize the changes of the entire organisms for hydrogen production 2)in another hand, to insert the hydrogenases in a photosynthetic chain and then to photo reduce them in order to obtain kinetic data to better understand how it works. (O.M.)

  16. Ultrafast Energy Transfer and Enhanced Two-Photon Absorption in a Novel Porphyrin Side-Chain Polymer

    Institute of Scientific and Technical Information of China (English)

    WANG Hui; HUANG Ya-Ping; DENG Li; ZHAO Fu-Li; LIN Wei-Zhu; WANG Jian; LIANG Zhao-Xi

    2004-01-01

    @@ Ultrafast relaxation processes and transient two-photon absorption are studied in a novel porphyrin side-chain polymer, 5-hydroxy-10, 15,20-triphenyl-porphyrin-poly(glycidyl methacrylate) (HTPP-PGMA), by using picosecond luminescence spectroscopy and femtosecond pump-probe techniques. HTPP-PGMA exhibits the ultrafast initial luminescence decay (~300ps), which is absent in the conventional porphyrin monomer such as TPP. Enhanced two-photon absorption was observed in HTPP-PGMA; the corresponding Im x(a) is about 2.8× 10-11 esu, which is almost one order of magnitude larger than that of the conventional porphyrin monomer (TPP) (~1.3 × 10-12 esu).The ultrafast energy transfer plays an important role in the excited-state relaxation dynamics observed in HTPPPGMA. The potential application of HTPP-PGMA in optical switching is discussed.

  17. A Small Molecule That Protects the Integrity of the Electron Transfer Chain Blocks the Mitochondrial Apoptotic Pathway.

    Science.gov (United States)

    Jiang, Xian; Li, Li; Ying, Zhengxin; Pan, Chenjie; Huang, Shaoqiang; Li, Lin; Dai, Miaomiao; Yan, Bo; Li, Ming; Jiang, Hui; Chen, She; Zhang, Zhiyuan; Wang, Xiaodong

    2016-07-21

    In response to apoptotic stimuli, mitochondria in mammalian cells release cytochrome c and other apoptogenic proteins, leading to the subsequent activation of caspases and apoptotic cell death. This process is promoted by the pro-apoptotic members of the Bcl-2 family of proteins, such as Bim and Bax, which, respectively, initiate and execute cytochrome c release from the mitochondria. Here we report the discovery of a small molecule that efficiently blocks Bim-induced apoptosis after Bax is activated on the mitochondria. The cellular target of this small molecule was identified to be the succinate dehydrogenase subunit B (SDHB) protein of complex II of the mitochondrial electron transfer chain (ETC). The molecule protects the integrity of the ETC and allows treated cells to continue to proliferate after apoptosis induction. Moreover, this molecule blocked dopaminergic neuron death and reversed Parkinson-like behavior in a rat model of Parkinson's disease. PMID:27447985

  18. A silica-immobilized pt2+catalyst for the selective, aerobic oxidation of methane via an electron-transfer chain

    Institute of Scientific and Technical Information of China (English)

    Zengjian An; Xiulian Pan; Xiumei Liu; Xiuwen Han; Xinhe Bao

    2008-01-01

    The combination of Pt2+, benzoquinone and NaNO2 forms an electron-transfer chain, which leads to the oxidation of methane by O2 in CF3COOH aqueous solution. The overall turnover number per hour (TOF) of methane at 120 ℃ is 0.5 h-1, however, only about one fourth (23%) of methane is converted to the desired product of methanol in the formation of CF3COOCH3. The over-oxidation of methane to CO2, over the catalyst with the Pt2+ species immobilized via 2,2'-bipyridyl as a ligand on the silica substrate, is depressed distinctly. Under the same conditions, the conversion to methanol dominates, and no CO2 is observed, on account of the over-oxidation of methane, as confirmed by the isotope experiment.

  19. DNAzyme-based biosensor for Cu(2+) ion by combining hybridization chain reaction with fluorescence resonance energy transfer technique.

    Science.gov (United States)

    Chen, Ying; Chen, Ling; Ou, Yidian; Wang, Zhenhua; Fu, Fengfu; Guo, Liangqia

    2016-08-01

    A novel signal amplification strategy based on Cu(2+)-dependent DNAzyme was developed for sensing Cu(2+) ion by combining hybridization chain reaction (HCR) with fluorescence resonance energy transfer (FRET) technique. In the presence of Cu(2+) ion, the substrate strands of Cu(2+)-dependent DNAzyme immobilized on magnetic beads were specifically cleaved and released. The released strands initiated the HCR process of hairpin H1 and H2 labeled with FAM as the donor and TAMRA as the acceptor, respectively. Long nicked dsDNA structures were self-assembled to bring the donor and the acceptor in close proximity, resulting in a FRET process. The relative ratio of fluorescent intensities of the acceptor and donor was used to quantitatively detect Cu(2+) ion with a limit of detection of 0.5nmolL(-1). This proposed biosensor was applied to detect Cu(2+) ion in tap water with satisfactory results. PMID:27216680

  20. Effect of Trapping Agent and Polystyrene Chain End Functionality on Radical Trap-Assisted Atom Transfer Radical Coupling

    Directory of Open Access Journals (Sweden)

    Elizabeth M. Carnicom

    2014-10-01

    Full Text Available Coupling reactions were performed to gauge the effect of the inclusion of a radical trap on the success of coupling reactions of monohalogenated polystyrene (PSX chains in atom transfer radical coupling (ATRC type reactions. The effect of both the specific radical trap chosen and the structure of the polymer chain end were evaluated by the extent of dimerization observed in a series of analogous coupling reactions. The commonly used radical trap 2-methyl-2-nitrosopropane (MNP showed the highest amounts of dimerization for PSX (X = Br, Cl compared to coupling reactions performed in its absence or with a different radical trap. A dinitroxide coupling agent was also studied with the extent of coupling nearly matching the effectiveness of MNP in RTA (Radical trap-assisted-ATRC reactions, while N-nitroso and electron rich nitroso coupling agents were the least effective. (2,2,6,6-Tetramethyl-piperin-l-yloxyl-capped PS (PS-TEMPO, prepared by NMP, was subjected to a coupling sequence conceptually similar to RTA-ATRC, but dimerization was not observed regardless of the choice of radical trap. Kinetic experiments were performed to observe rate changes on the coupling reaction of PSBr as a result of the inclusion of MNP, with substantial rate enhancements found in the RTA-ATRC coupling sequence compared to traditional ATRC.

  1. Arsenic contamination in food-chain: transfer of arsenic into food materials through groundwater irrigation.

    Science.gov (United States)

    Huq, S M Imamul; Joardar, J C; Parvin, S; Correll, Ray; Naidu, Ravi

    2006-09-01

    Arsenic contamination in groundwater in Bangladesh has become an additional concern vis-à-vis its use for irrigation purposes. Even if arsenic-safe drinking-water is assured, the question of irrigating soils with arsenic-laden groundwater will continue for years to come. Immediate attention should be given to assess the possibility of accumulating arsenic in soils through irrigation-water and its subsequent entry into the food-chain through various food crops and fodders. With this possibility in mind, arsenic content of 2,500 water, soil and vegetable samples from arsenic-affected and arsenic-unaffected areas were analyzed during 1999-2004. Other sources of foods and fodders were also analyzed. Irrigating a rice field with groundwater containing 0.55 mg/L of arsenic with a water requirement of 1,000 mm results in an estimated addition of 5.5 kg of arsenic per ha per annum. Concentration of arsenic as high as 80 mg per kg of soil was found in an area receiving arsenic-contaminated irrigation. A comparison of results from affected and unaffected areas revealed that some commonly-grown vegetables, which would usually be suitable as good sources of nourishment, accumulate substantially-elevated amounts of arsenic. For example, more than 150 mg/kg of arsenic has been found to be accumulated in arum (kochu) vegetable. Implications of arsenic ingested in vegetables and other food materials are discussed in the paper. PMID:17366772

  2. The transfer of titanium dioxide nanoparticles from the host plant to butterfly larvae through a food chain

    Science.gov (United States)

    Kubo-Irie, Miyoko; Yokoyama, Masaaki; Shinkai, Yusuke; Niki, Rikio; Takeda, Ken; Irie, Masaru

    2016-03-01

    This study aimed to examine the transfer of nanoparticles within a terrestrial food chain. Oviposited eggs of the swallowtail butterfly (Atrophaneura alcinous) were hatched on the leaves of the host plant (Aristolochia debilis), and the root stock and root hairs were submerged in a suspension of 10 μg/ml titanium dioxide nanoparticles (TiO2-NPs) in a 100 ml bottle. The presence of TiO2-NPs in the veins of the leaves was confirmed by X-ray analytical microscopy (X-ray AM). The hatched 1st instar larvae fed on the leaves to moult into 2nd instar larvae. Small agglomerates of TiO2-NPs less than 150 nm in diameter were identified in the vascular tissue of the exposed plant, the midgut and the excreta of the larvae by transmission electron microscopy. The image of Ti elemental mapping by X-ray AM was analysed with the quantitative spatial information mapping (QSIM) technique. The results demonstrated that TiO2-NPs were transferred from the plant to the larvae and they were disseminated throughout the environment via larval excreta.

  3. A new classification of free combined or connected tissue transfers: introduction to the concept of bridge, siamese, chimeric, mosaic, and chain-circle flaps.

    OpenAIRE

    Koshima, Isao

    2001-01-01

    Recently, combined tissues or flaps have been used for the repair of extensively massive or wide defects resulting from radical wide resection. To further advance the development of combined tissue transfers, they should be reclassified. Based on our cases with free tissue transfers, we have created a new classification of combined flaps composed of "bridge", "chimeric", "siamese", "mosaic", and "chain-circle" flaps. The bridge flap is fabricated out together of separate flaps with short vasc...

  4. Neutral-Type One-Dimensional Mixed-Valence Halogen-Bridged Platinum Chain Complexes with Large Charge-Transfer Band Gaps.

    Science.gov (United States)

    Otake, Ken-ichi; Otsubo, Kazuya; Sugimoto, Kunihisa; Fujiwara, Akihiko; Kitagawa, Hiroshi

    2016-03-01

    One-dimensional (1D) electronic systems have attracted significant attention for a long time because of their various physical properties. Among 1D electronic systems, 1D halogen-bridged mixed-valence transition-metal complexes (the so-called MX chains) have been thoroughly studied owing to designable structures and electronic states. Here, we report the syntheses, structures, and electronic properties of three kinds of novel neutral MX-chain complexes. The crystal structures consist of 1D chains of Pt-X repeating units with (1R,2R)-(-)-diaminocychlohexane and CN(-) in-plane ligands. Because of the absence of a counteranion, the neutral MX chains have short interchain distances, so that strong interchain electronic interaction is expected. Resonance Raman spectra and diffuse-reflectance UV-vis spectra indicate that their electronic states are mixed-valence states (charge-density-wave state: Pt(2+)···X-Pt(4+)-X···Pt(2+)···X-Pt(4+)-X···). In addition, the relationship between the intervalence charge-transfer (IVCT) band gap and the degree of distortion of the 1D chain shows that the neutral MX chains have a larger IVCT band gap than that of cationic MX-chain complexes. These results provide new insight into the physical and electronic properties of 1D chain compounds. PMID:26901774

  5. Metal Ion-dependent Heavy Chain Transfer Activity of TSG-6 Mediates Assembly of the Cumulus-Oocyte Matrix.

    Science.gov (United States)

    Briggs, David C; Birchenough, Holly L; Ali, Tariq; Rugg, Marilyn S; Waltho, Jon P; Ievoli, Elena; Jowitt, Thomas A; Enghild, Jan J; Richter, Ralf P; Salustri, Antonietta; Milner, Caroline M; Day, Anthony J

    2015-11-27

    The matrix polysaccharide hyaluronan (HA) has a critical role in the expansion of the cumulus cell-oocyte complex (COC), a process that is necessary for ovulation and fertilization in most mammals. Hyaluronan is organized into a cross-linked network by the cooperative action of three proteins, inter-α-inhibitor (IαI), pentraxin-3, and TNF-stimulated gene-6 (TSG-6), driving the expansion of the COC and providing the cumulus matrix with its required viscoelastic properties. Although it is known that matrix stabilization involves the TSG-6-mediated transfer of IαI heavy chains (HCs) onto hyaluronan (to form covalent HC·HA complexes that are cross-linked by pentraxin-3) and that this occurs via the formation of covalent HC·TSG-6 intermediates, the underlying molecular mechanisms are not well understood. Here, we have determined the tertiary structure of the CUB module from human TSG-6, identifying a calcium ion-binding site and chelating glutamic acid residue that mediate the formation of HC·TSG-6. This occurs via an initial metal ion-dependent, non-covalent, interaction between TSG-6 and HCs that also requires the presence of an HC-associated magnesium ion. In addition, we have found that the well characterized hyaluronan-binding site in the TSG-6 Link module is not used for recognition during transfer of HCs onto HA. Analysis of TSG-6 mutants (with impaired transferase and/or hyaluronan-binding functions) revealed that although the TSG-6-mediated formation of HC·HA complexes is essential for the expansion of mouse COCs in vitro, the hyaluronan-binding function of TSG-6 does not play a major role in the stabilization of the murine cumulus matrix.

  6. Ethylene homo- and copolymerization chain-transfers: A perspective from supported (n BuCp) 2 ZrCl 2 catalyst active centre distribution

    KAUST Repository

    Atiqullah, Muhammad

    2015-04-01

    Polymerization chain termination reactions and unsaturation of the polymer backbone end are related. Therefore, in this study, the parameters resulting from the modelling of the active centre distribution of the supported catalyst - silica/MAO/(nBuCp)2ZrCl2 - were applied to evaluate the active-centre-dependent ethylene homo- and copolymerization rates, as well as the corresponding chain termination rates. This approach, from a microkinetic mechanistic viewpoint, elucidates better the 1-hexene-induced positive comonomer effect and chain transfer phenomenon. The kinetic expressions, developed on the basis of the proposed polymerization mechanisms, illustrate how the active site type-dependent chain transfer phenomenon is influenced by the different apparent termination rate constants and momoner concentrations. The active centre-specific molecular weight M ni (for the above homo- and copolymer), as a function of chain transfer probability, p CTi, varied as follows: log (p C Ti) = log (mwru) - log (Mn i), where mw ru is the molecular weight of the repeat unit. The physical significance of this finding has been explained. The homo- and copolymer backbones showed all the three chain end unsaturations (vinyl, vinylidene, and trans-vinylene). The postulated polymerization mechanisms reveal the underlying polymer chemistry. The results of the present study will contribute to develop in future supported metallocene catalysts that will be useful to synthesize polyethylene precursors having varying chain end unsaturations, which can be eventually used to prepare functional polyethylenes. [Figure not available: see fulltext.] © 2015 Indian Academy of Sciences.

  7. Food chain transfer of cadmium and lead to cattle in a lead-zinc smelter in Guizhou, China

    Energy Technology Data Exchange (ETDEWEB)

    Cai Qiu, E-mail: caiqiu1029@126.co [Guizhou Import-Export Inspection Bureau, 4 Beijing Road, Guiyang 550004 (China); Long Meili [Guizhou Academy of Sciences, Guiyang 550001 (China); Zhu Ming [Guizhou Import-Export Inspection Bureau, 4 Beijing Road, Guiyang 550004 (China); Zhou Qingzhen [Guizhou Academy of Sciences, Guiyang 550001 (China); Zhang Ling [Guizhou Import-Export Inspection Bureau, 4 Beijing Road, Guiyang 550004 (China); Liu Jie, E-mail: jie@liuonline.co [Zunyi Medical College, Zunyi 563003 (China)

    2009-11-15

    Cadmium (Cd) and Lead (Pb) are environmental pollutants. Environmental samples and bovine tissues were collected from the areas around a lead-zinc smelter in Guizhou, China for Cd, Pb, zinc (Zn) and copper (Cu) analysis. Cd in soil (10 mg/kg) and feed (6.6 mg/kg) from the polluted areas was 10 times higher than the Chinese Standards, resulting in higher Cd in bovine kidney (38 mg/kg) and liver (2.5 mg/kg). Pb in feed (132 mg/kg) from the polluted area was much higher than unpolluted areas, causing higher Pb levels in bovine tissues. Environmental Zn was elevated, but bovine tissue Zn was normal. Cu in bovine liver decreased with increased Cd and Pb. Metals in drinking water and in bovine muscle were within the Standard range. Thus, in the areas of this lead-zinc smelter, the environment has been contaminated with Cd and Pb, which has been transferred to cattle through the food chain. - Cd and Pb from lead-zinc smelters contaminate the environment and accumulate in bovine tissues.

  8. Food chain transfer of cadmium and lead to cattle in a lead-zinc smelter in Guizhou, China.

    Science.gov (United States)

    Cai, Qiu; Long, Mei-Li; Zhu, Ming; Zhou, Qing-Zhen; Zhang, Ling; Liu, Jie

    2009-11-01

    Cadmium (Cd) and Lead (Pb) are environmental pollutants. Environmental samples and bovine tissues were collected from the areas around a lead-zinc smelter in Guizhou, China for Cd, Pb, zinc (Zn) and copper (Cu) analysis. Cd in soil (10 mg/kg) and feed (6.6 mg/kg) from the polluted areas was 10 times higher than the Chinese Standards, resulting in higher Cd in bovine kidney (38 mg/kg) and liver (2.5 mg/kg). Pb in feed (132 mg/kg) from the polluted area was much higher than unpolluted areas, causing higher Pb levels in bovine tissues. Environmental Zn was elevated, but bovine tissue Zn was normal. Cu in bovine liver decreased with increased Cd and Pb. Metals in drinking water and in bovine muscle were within the Standard range. Thus, in the areas of this lead-zinc smelter, the environment has been contaminated with Cd and Pb, which has been transferred to cattle through the food chain. PMID:19573961

  9. Xanthohumol induces generation of reactive oxygen species and triggers apoptosis through inhibition of mitochondrial electron transfer chain complex I.

    Science.gov (United States)

    Zhang, Bo; Chu, Wei; Wei, Peng; Liu, Ying; Wei, Taotao

    2015-12-01

    Xanthohumol is a prenylflavonoid extracted from hops (Humulus lupulus). It possesses anti-cancer and anti-inflammatory activities in vitro and in vivo, and offers therapeutic benefits for treatment of metabolic syndromes. However, the precise mechanisms underlying its pharmacological effects remain to be elucidated, together with its cellular target. Here, we provide evidence that xanthohumol directly interacts with the mitochondrial electron transfer chain complex I (NADH dehydrogenase), inhibits the oxidative phosphorylation, triggers the production of reactive oxygen species, and induces apoptosis. In addition, we show that as a result of the inhibition of the mitochondrial oxidative phosphorylation, xanthohumol exposure causes a rapid decrease of mitochondrial transmembrane potential. Furthermore, we showed that xanthohumol up-regulates the glycolytic capacity in cells, and thus compensates cellular ATP generation. Dissection of the multiple steps of aerobic respiration by extracellular flux assays revealed that xanthohumol specifically inhibits the activity of mitochondrial complex I, but had little effect on that of complex II, III and IV. Inhibition of complex I by xanthohumol caused the overproduction of reactive oxygen species, which are responsible for the induction of apoptosis in cancer cells. We also found that isoxanthohumol, the structural isomer of xanthohumol, is inactive to cells, suggesting that the reactive 2-hydroxyl group of xanthohumol is crucial for its targeting to the mitochondrial complex I. Together, the remodeling of cell metabolism revealed here has therapeutic potential for the use of xanthohumol.

  10. A hermetic self-sustained microbial solar cell based on Chlorella vulgaris and a versatile charge transfer chain

    Science.gov (United States)

    Pan, Keliang; Zhou, Peijiang

    2015-10-01

    A hermetic noble-metal-free membrane-less microbial solar cell (MSC) is established. The substances decomposition and regeneration in this MSC are carried out only by Chlorella vulgaris simultaneously. The conversion of metabolism types of C. vulgaris is controlled only by illumination. By using a pleiotropic redox mediator and a cupric hexacyanoferrate modified cathode, a two-phase three-stage charge transfer chain is formed. Through this pathway, the one microorganism self-sustained system gets a long-term power output up to 0.04773 mW/cm2 at 0.423 V without any material exchange with external, which is 50 times higher than that obtained from the original system. Benefiting from this electron buffer system, the battery will achieve an electricity generation in both light and dark conditions. There is almost no consumption of any substrates throughout the stabilized process, and no more additions are required. This maintenance-free and extremely inexpensive reactor with a simple structure and a long service life demonstrates the possibility of combining the microbial, chemical and photo cells.

  11. Markov Chain Method for Radiative Transfer Modeling: A Case Study of Aerosol/Surface Retrieval using AirMSPI Measurements

    Science.gov (United States)

    Xu, F.; Diner, D. J.; Davis, A. B.; Latyshev, S.; Garay, M. J.; Kalashnikova, O.; Ge, C.; Wang, J.

    2013-12-01

    A vector Markov chain (MarCh) radiative transfer (RT) code developed at JPL that includes forward modeling of radiance and polarization fields and linearization (analytical estimation of Jacobians) was incorporated into an aerosol and surface retrieval package for a plane-parallel atmosphere/surface system. The RT computation by MarCh is based on matrix operations. To improve the code's computational efficiency, the forward model is currently undergoing acceleration through the exploration of different strategies for matrix operation and inversion, including numerical optimization, multi-threading/multi-processing techniques on a CPU. Implementation on a graphics processing unit (GPU) is also planned. Following a benchmarking study of the forward model, the performance of MarCh in aerosol and surface retrieval is being tested. With an optimized algorithm, we started from aerosol optical depth and surface retrieval using imagery acquired by Airborne Multiangle SpectroPolarimetric Imager (AirMSPI) over Fresno, CA. Aerosol properties including concentration and size distribution of different species provided by the Weather Research and Forecasting (WRF)-Chem model were used to constrain the retrieval and reduce the parameter space. The assumptions of spectral invariance in the angular shape of surface bidirectional reflectance factors (BRFs) and the magnitude of polarized surface BRFs were tested. The aerosol and surface properties are then relaxed in a stepwise way to refine the aerosol retrieval results and enable comparison with independent retrievals obtained from a collocated AErosol RObotic NETwork (AERONET) station.

  12. Falling chains

    Science.gov (United States)

    Wong, Chun Wa; Yasui, Kosuke

    2006-06-01

    The one-dimensional fall of a folded chain with one end suspended from a rigid support and a chain falling from a resting heap on a table is studied. Because their Lagrangians contain no explicit time dependence, the falling chains are conservative systems. Their equations of motion are shown to contain a term that enforces energy conservation when masses are transferred between subchains. We show that Cayley's 1857 energy nonconserving solution for a chain falling from a resting heap is incorrect because it neglects the energy gained when a link leaves a subchain. The maximum chain tension measured by Calkin and March for the falling folded chain is given a simple if rough interpretation. Other aspects of the falling folded chain are briefly discussed.

  13. 一种信任链传递模型研究%Research of a Trust Chain Transfer Model

    Institute of Scientific and Technical Information of China (English)

    司丽敏; 蔡勉; 陈银镜; 郭颖

    2011-01-01

    Based on measurement applications and its dynamic library to protect the integrity of the application of static credible,and analyzing the relation between interactive applications, this article established chain of trust of the transfer model, to protect applications running in the process of dynamic credible, to build reliable application environment Based on the intransitive noninterference model,this article abstracted the system as applications,actions,states and outputs, and formally defined to run trusted applications. Application trusted theorem was verified formally. Furthermore, by as sociating application with system state, the definition and the theorem of application environment trusted were pro posed.%通过度量应用程序及其动态库的完整性来保障应用的静态可信,并且分析有交互的应用之间的关系,建立了一种信任链传递模型来保障应用运行过程中的动态可信,从而构建可信的应用环境.并基于无干扰理论,将系统抽象为应用程序、动作和状态输出,形式化地定义了应用运行可信,给出应用运行可信的条件和性质,推出应用运行可信定理,并证明了基于该模型的应用环境可信判定定理.

  14. Falling chains

    CERN Document Server

    Wong, C W; Wong, Chun Wa; Yasui, Kosuke

    2006-01-01

    The one-dimensional falling motion of a bungee chain suspended from a rigid support and of a chain falling from a resting heap on a table is studied. Their Lagrangians are found to contain no explicit time dependence. As a result, these falling chains are conservative systems. Each of their Lagrange's equations of motion is shown to contain a term that enforces energy conservation when masses are transferred between subchains. We show in particular that Cayley's 1857 energy nonconserving solution for a chain falling from a resting heap is incorrect because it neglects the energy gained when the transferred link is emitted by the emitting subchain. The maximum chain tension measured by Calkin and March for the falling bungee chain is given a simple if rough interpretation. In the simplified one-dimensional treatment, the kinetic energy of the center of mass of the falling bungee chain is found to be converted by the chain tension at the rigid support into the internal kinetic energy of the chain. However, as t...

  15. Main-Chain and Side-Chain Sequence-Regulated Vinyl Copolymers by Iterative Atom Transfer Radical Additions and 1:1 or 2:1 Alternating Radical Copolymerization.

    Science.gov (United States)

    Soejima, Takamasa; Satoh, Kotaro; Kamigaito, Masami

    2016-01-27

    Main- and side-chain sequence-regulated vinyl copolymers were prepared by a combination of iterative atom transfer radical additions (ATRAs) of vinyl monomers for side-chain control and 1:1 or 2:1 alternating radical copolymerization of the obtained side-chain sequenced "oligomonomers" and vinyl comonomers for main-chain control. A complete set of sequence-regulated trimeric vinyl oligomers of styrene (S) and/or methyl acrylate (A) were first synthesized via iterative ATRAs of these monomers to a halide of monomeric S or A unit (X-S or X-A) under optimized conditions with appropriate ruthenium or copper catalysts, which were selected depending on the monomers and halides. The obtained halogen-capped oligomers were then converted into a series of maleimide (M)-ended oligomonomers with different monomer compositions and sequences (M-SSS, M-ASS, M-SAS, M-AAS, M-SSA, M-ASA, M-SAA, M-AAA) by a substitution reaction of the halide with furan-protected maleimide anion followed by deprotection of the furan units. These maleimide-ended oligomonomers were then radically copolymerized with styrene or limonene to enable the 1:1 or 2:1 monomer-sequence regulation in the main chain and finally result in the main- and side-chain sequence-regulated vinyl copolymers with high molecular weights in high yield. The properties of the sequence-regulated vinyl copolymers depended on not only the monomer compositions but also the monomer sequences. The solubility was highly affected by the outer monomer units in the side chains whereas the glass transition temperatures were primarily affected by the two successive monomer sequences. PMID:26761148

  16. Transfer

    DEFF Research Database (Denmark)

    Wahlgren, Bjarne; Aarkrog, Vibe

    Bogen er den første samlede indføring i transfer på dansk. Transfer kan anvendes som praksis-filosofikum. Den giver en systematisk indsigt til den studerende, der spørger: Hvordan kan teoretisk viden bruges til at reflektere over handlinger i situationer, der passer til min fremtidige arbejdsplads?...

  17. Trophic transfer of lead through a model marine four-level food chain: Tetraselmis suecica, Artemia franciscana, Litopenaeus vannamei, and Haemulon scudderi.

    Science.gov (United States)

    Soto-Jiménez, M F; Arellano-Fiore, C; Rocha-Velarde, R; Jara-Marini, M E; Ruelas-Inzunza, J; Páez-Osuna, F

    2011-08-01

    The objective of this investigation was to assess the transfer of lead (Pb) along an experimental, four-level food chain: Tetraselmis suecica (phytoplankton) → Artemia franciscana (crustacean, brine shrimp) → Litopenaeus vannamei (crustacean, white shrimp) → Haemulon scudderi (fish, grunt). T. suecica was exposed to a sublethal dose of Pb in solution and then used as the base of a marine food chain. Significant differences in Pb concentrations were found between exposed organisms of the different trophic levels and the control. Particularly, Pb concentrations in fish of the simulated trophic chain were two-to three times higher in the exposed specimens than in the control. Levels of Pb in phytoplankton showed a substantial increase with respect to the solution (level I), with bioconcentration factors averaging from 930 to 3630. In contrast, a strong decrease in Pb concentration from phytoplankton to zooplankton (level II) and from zooplankton to shrimp tissues (level III) was evidenced by bioaccumulation factors metal transfer observed in these two predators, Pb concentration in the grunt fish (level IV) was higher than in the shrimp (level III) (bioaccumulation factor >1.0). Some of the added Pb is transferred from the phytoplankton along the food chain, thus producing a net accumulation of Pb mainly in fish and, to a lesser extent, in shrimp tissues. Because Pb is one of the most pervasive contaminants in coastal ecosystems, its transference by way of diet and potential net accumulation in higher predators is of ecologic importance for marine life. In addition, because shrimp and adult Haemulon scudderi are commercially important resources, this issue is of particular relevance to the safety of marine products. PMID:21082317

  18. Calibration chain design based on integrating sphere transfer radiometer for SI-traceable on-orbit spectral radiometric calibration and its uncertainty analysis

    Science.gov (United States)

    Zhao, Wei-Ning; Fang, Wei; Sun, Li-Wei; Cui, Li-Hong; Wang, Yu-Peng

    2016-09-01

    In order to satisfy the requirement of SI-traceable on-orbit absolute radiation calibration transfer with high accuracy for satellite remote sensors, a transfer chain consisting of a fiber coupling monochromator (FBM) and an integrating sphere transfer radiometer (ISTR) was designed in this paper. Depending on the Sun, this chain based on detectors provides precise spectral radiometric calibration and measurement to spectrometers in the reflective solar band (RSB) covering 300-2500 nm with a spectral bandwidth of 0.5-6 nm. It shortens the traditional chain based on lamp source and reduces the calibration uncertainty from 5% to 0.5% by using the cryogenic radiometer in space as a radiometric benchmark and trap detectors as secondary standard. This paper also gives a detailed uncertainty budget with reasonable distribution of each impact factor, including the weak spectral signal measurement with uncertainty of 0.28%. According to the peculiar design and comprehensive uncertainty analysis, it illustrates that the spectral radiance measurement uncertainty of the ISTR system can reach to 0.48%. The result satisfies the requirements of SI-traceable on-orbit calibration and has wider significance for expanding the application of the remote sensing data with high-quality. Project supported by the National Natural Science Foundation of China (Grant No. 41474161) and the National High-Technology Program of China (Grant No. 2015AA123703).

  19. Building Pathways to Transfer: Community Colleges That Break the Chain of Failure for Students of Color. Policy Brief

    Science.gov (United States)

    Civil Rights Project / Proyecto Derechos Civiles, 2012

    2012-01-01

    This study followed all freshman community college students in California who had demonstrated the intent to transfer from 1996, 1997, and 1998. Outcomes were assessed for each of the three entering cohorts after six years (2002-2004) and students were linked with their high schools of origin and the 4-year colleges to which they transferred. The…

  20. Factors affecting the concentration in seven-spotted ladybirds (Coccinella septempunctata L.) of Cd and Zn transferred through the food chain

    Energy Technology Data Exchange (ETDEWEB)

    Green, I.D., E-mail: igreen@bournemouth.ac.u [Centre for Conservation Ecology and Environmental Change, School of Conservation Sciences, Bournemouth University, Talbot Campus, Poole, Dorset BH12 5BB (United Kingdom); Diaz, A., E-mail: adiaz@bournemouth.ac.u [Centre for Conservation Ecology and Environmental Change, School of Conservation Sciences, Bournemouth University, Talbot Campus, Poole, Dorset BH12 5BB (United Kingdom); Tibbett, M., E-mail: mark.tibbett@uwa.edu.a [Centre for Land Rehabilitation, School of Earth and Environment, Faculty of Natural and Agricultural Sciences, University of Western Australia, 35 Stirling Highway, Crawley WA 6009 (Australia)

    2010-01-15

    The transfer of Cd and Zn from soils amended with sewage sludge was followed through a food chain consisting of wheat, aphids and the predator Coccinella septempunctata. Multiple regression models were generated to predict the concentrations of Cd and Zn in C. septempunctata. No significant model could be generated for Cd, indicting that the concentration of this metal was maintained within relatively narrow limits. A model predicting 64% of the variability in the Zn concentration of C. septempunctata was generated from of the concentration of Zn in the diet, time and rate of Zn consumption. The results suggest that decreasing the rate of food consumption is an effective mechanism to prevent the accumulation of Zn and that the availability of Zn in the aphid prey increased with the concentration in the aphids. The results emphasise the importance of using ecologically relevant food chains and exposure pathways during ecotoxicological studies. - Arthropod predators can regulate trace metal body burden through physiological and behavioural mechanisms.

  1. Unraveling the evolutionary history of the phosphoryl-transfer chain of the phosphoenolpyruvate:phosphotransferase system through phylogenetic analyses and genome context

    Directory of Open Access Journals (Sweden)

    Zúñiga Manuel

    2008-05-01

    Full Text Available Abstract Background The phosphoenolpyruvate phosphotransferase system (PTS plays a major role in sugar transport and in the regulation of essential physiological processes in many bacteria. The PTS couples solute transport to its phosphorylation at the expense of phosphoenolpyruvate (PEP and it consists of general cytoplasmic phosphoryl transfer proteins and specific enzyme II complexes which catalyze the uptake and phosphorylation of solutes. Previous studies have suggested that the evolution of the constituents of the enzyme II complexes has been driven largely by horizontal gene transfer whereas vertical inheritance has been prevalent in the general phosphoryl transfer proteins in some bacterial groups. The aim of this work is to test this hypothesis by studying the evolution of the phosphoryl transfer proteins of the PTS. Results We have analyzed the evolutionary history of the PTS phosphoryl transfer chain (PTS-ptc components in 222 complete genomes by combining phylogenetic methods and analysis of genomic context. Phylogenetic analyses alone were not conclusive for the deepest nodes but when complemented with analyses of genomic context and functional information, the main evolutionary trends of this system could be depicted. Conclusion The PTS-ptc evolved in bacteria after the divergence of early lineages such as Aquificales, Thermotogales and Thermus/Deinococcus. The subsequent evolutionary history of the PTS-ptc varied in different bacterial lineages: vertical inheritance and lineage-specific gene losses mainly explain the current situation in Actinobacteria and Firmicutes whereas horizontal gene transfer (HGT also played a major role in Proteobacteria. Most remarkably, we have identified a HGT event from Firmicutes or Fusobacteria to the last common ancestor of the Enterobacteriaceae, Pasteurellaceae, Shewanellaceae and Vibrionaceae. This transfer led to extensive changes in the metabolic and regulatory networks of these bacteria

  2. Measuring distances within unfolded biopolymers using fluorescence resonance energy transfer: The effect of polymer chain dynamics on the observed fluorescence resonance energy transfer efficiency

    Science.gov (United States)

    Makarov, Dmitrii E.; Plaxco, Kevin W.

    2009-01-01

    Recent years have seen a number of investigations in which distances within unfolded proteins, polypeptides, and other biopolymers are probed via fluorescence resonance energy transfer, a method that relies on the strong distance dependence of energy transfer between a pair of dyes attached to the molecule of interest. In order to interpret the results of such experiments it is commonly assumed that intramolecular diffusion is negligible during the excited state lifetime. Here we explore the conditions under which this “frozen chain” approximation fails, leading to significantly underestimated donor-acceptor distances, and describe a means of correcting for polymer dynamics in order to estimate these distances more accurately. PMID:19725638

  3. Slow and fast singlet energy transfers in BODIPY-gallium(III)corrole dyads linked by flexible chains.

    Science.gov (United States)

    Brizet, Bertrand; Desbois, Nicolas; Bonnot, Antoine; Langlois, Adam; Dubois, Adrien; Barbe, Jean-Michel; Gros, Claude P; Goze, Christine; Denat, Franck; Harvey, Pierre D

    2014-04-01

    Red (no styryl), green (monostyryl), and blue (distyryl) BODIPY-gallium(III) (BODIPY = boron-dipyrromethene) corrole dyads have been prepared in high yields using click chemistry, and their photophysical properties are reported. An original and efficient control of the direction of the singlet energy transfers is reported, going either from BODIPY to the gallium-corrole units or from gallium-corroles to BODIPY, depending upon the nature of the substitution on BODIPY. In one case (green), both directions are possible. The mechanism for the energy transfers is interpreted by means of through-space Förster resonance energy transfer (FRET). PMID:24661249

  4. Transfer of radiocaesium from contaminated bottom sediments to marine organisms through benthic food chains in post-Fukushima and post-Chernobyl periods

    Science.gov (United States)

    Bezhenar, Roman; Jung, Kyung Tae; Maderich, Vladimir; Willemsen, Stefan; de With, Govert; Qiao, Fangli

    2016-05-01

    After the earthquake and tsunami on 11 March 2011 damaged the Fukushima Dai-ichi Nuclear Power Plant (FDNPP), an accidental release of a large amount of radioactive isotopes into both the air and the ocean occurred. Measurements provided by the Japanese agencies over the past 5 years show that elevated concentrations of 137Cs still remain in sediments, benthic organisms, and demersal fishes in the coastal zone around the FDNPP. These observations indicate that there are 137Cs transfer pathways from bottom sediments to the marine organisms. To describe the transfer quantitatively, the dynamic food chain biological uptake model of radionuclides (BURN) has been extended to include benthic marine organisms. The extended model takes into account both pelagic and benthic marine organisms grouped into several classes based on their trophic level and type of species: phytoplankton, zooplankton, and fishes (two types: piscivorous and non-piscivorous) for the pelagic food chain; deposit-feeding invertebrates, demersal fishes fed by benthic invertebrates, and bottom omnivorous predators for the benthic food chain; crustaceans, mollusks, and coastal predators feeding on both pelagic and benthic organisms. Bottom invertebrates ingest organic parts of bottom sediments with adsorbed radionuclides which then migrate up through the food chain. All organisms take radionuclides directly from water as well as food. The model was implemented into the compartment model POSEIDON-R and applied to the north-western Pacific for the period of 1945-2010, and then for the period of 2011-2020 to assess the radiological consequences of 137Cs released due to the FDNPP accident. The model simulations for activity concentrations of 137Cs in both pelagic and benthic organisms in the coastal area around the FDNPP agree well with measurements for the period of 2011-2015. The decrease constant in the fitted exponential function of simulated concentration for the deposit-feeding invertebrates (0.45 yr-1

  5. Toxicity and transfer of polyvinylpyrrolidone-coated silver nanowires in an aquatic food chain consisting of algae, water fleas, and zebrafish.

    Science.gov (United States)

    Chae, Yooeun; An, Youn-Joo

    2016-04-01

    Nanomaterials of various shapes and dimensions are widely used in the medical, chemical, and electronic industries. Multiple studies have reported the ecotoxicological effects of nanaoparticles when released in aquatic and terrestrial ecosystems; however, information on the toxicity of silver nanowires (AgNWs) to freshwater organisms and their transfer through the food webs is limited. In the present study, we aimed to evaluate the toxicity of 10- and 20-μm-long AgNWs to the alga Chlamydomonas reinhardtii, the water flea Daphnia magna, and the zebrafish and study their movement through this three-species food chain using a variety of qualitative and quantitative methods as well as optical techniques. We found that AgNWs directly inhibited the growth of algae and destroyed the digestive organs of water fleas. The results showed that longer AgNWs (20μm) were more toxic than shorter ones (10μm) to both algae and water fleas, but shorter AgNWs were accumulated more than longer ones in the body of the fish. Overall, this study suggests that AgNWs are transferred through food chains, and that they affect organisms at higher trophic levels, potentially including humans. Therefore, further studies that take into account environmental factors, food web complexity, and differences between nanomaterials are required to gain better understanding of the impact of nanomaterials on natural communities and human health. PMID:26854872

  6. Reliability Measurement for Software with Variable Length Markov Control Transfer Chain%VLMC控制流软件可靠性度量方法

    Institute of Scientific and Technical Information of China (English)

    赵瑞曼; 潘冠华; 方建勇

    2014-01-01

    The classical software reliability model of Cheung based on architecture analysis is imperfect when applied to soft-ware which has non-uniqueness terminal node because of ideal assumptions. In order to handle this problem, an improved model is established through two improvement as follows:first, probability matrix of control transfer from start node to other inner nodes in a given software is computed independently of control transfer within inner nodes on the assumptions that the start node is inaccessible to control transfer from any inner nodes;and then, probability matrixes of control transfer within in-ner nodes are reconfigured by weaken the difference between inner nodes and ending nodes. In order to measure the reliability of software with VLMC control transfer flow, the variable length Markov control sequence chain is converted to simple Markov chain by node expansion and conditional transfer probability redistribution. By using deductive inference, a formal proof for the new model is given in this essay. In the end, effectiveness and simplicity of the proposed method is verified by a software example.%针对现有软件可靠性模型普遍不适用于实际软件的问题,分析了软件内部模块间控制转移机理,通过分离入口模块,提取一阶控制转移概率矩阵;弱化内部模块与出口模块间差异,重构二阶以上转移概率矩阵,在改进Cheung模型的基础上建立一个更符合软件实际的可靠性度量模型。针对变阶依赖( VLMC)控制转移导致的可靠性度量难问题,通过对导致复杂依赖的多入多出模块进行节点扩展,将VLMC控制流转化为Markov链,利用所建立的软件可靠性模型对VLMC控制流软件进行可靠性度量。研究利用演绎推理对所建立模型进行了正确性形式化证明。最后给出了方法的实例验证。

  7. A tentative assessment of cesium 137 direct and indirect transfer rates in a simplified fresh water food chain

    International Nuclear Information System (INIS)

    A comparison was made of the direct transfer of cesium from water to carps and the indirect transfer via the food. In a first experiment on chronic contamination of carps by water, the kinetics and distribution of cesium in the organs of the carps were studied. Equilibrium was not reached on the 56th day, 4% of the initial water activity had been retained by the carps and the concentration factor was below 10. The highest specific activities were found in the transit organs. In a second experiment, the water activity varied by alternating contamination and decontamination. A fluctuating equilibrium was reached on the 22nd day. The concentration factor was of the same order of magnitude than in the previous experiment. Indirect contamination of fish by ingestion of contaminated daphnids was studied in a third experiment. Cesium levels in carps increased with the cumulated activities in meals, and the uptake rate in fish was 4%. Both decorporation and biological half-lives (30-40 days) were independent of the contamination routes. The respective significance of the transfer pathways is discussed taking into account the biomass pyramids to be found in the nature. It is estimated that in a cesium environment, 70% of the carp activity should come from the diet and 30% from the water. The concentration factor would then be 75 instead of 22 when only direct transfer of cesium from water to fish is considered

  8. A new classification of free combined or connected tissue transfers: introduction to the concept of bridge, siamese, chimeric, mosaic, and chain-circle flaps.

    Directory of Open Access Journals (Sweden)

    Koshima I

    2001-12-01

    Full Text Available Recently, combined tissues or flaps have been used for the repair of extensively massive or wide defects resulting from radical wide resection. To further advance the development of combined tissue transfers, they should be reclassified. Based on our cases with free tissue transfers, we have created a new classification of combined flaps composed of "bridge", "chimeric", "siamese", "mosaic", and "chain-circle" flaps. The bridge flap is fabricated out together of separate flaps with short vascular pedicles. These form a compound flap supplied with a solitary vascular source. The chimeric flap is compounded from multiple different flaps but consists of only a single different tissue form. Each of the flaps is usually supplied by different branches from the same source vessel. It differs from the bridge flap in that the pedicle of each flap or tissue has some length for its movement for transfer. The siamese connected flap has 2 adjacent flaps that are simultaneously elevated, and a disparate vascular pedicle for each flap must be reestablished. This connected flap has double isolated pedicles. Themosaic connected flap consists of 2 adjacent flaps that are simultaneously elevated, and the pedicle of the distal flap is anastomosed to the pedicle branch of the proximal flap in the "bridge" fashion. The vascular pedicle of the proximal flap is anastomosed to a single vascular source. The chain-circle flap has 2 or more flaps like the bridge and chimeric flaps, and the distal end of the vascular source is anastomosed to the branch of the recipient vessel. Based on results with our patients, the lateral circumflex femoral system seems to be the most suitable candidate for the axial pedicle of these combined flaps, because the system has several branches of large and small caliber, and several tissue components, such as the vascularized ilium, rectus femoris muscle, gracilis muscle, lateral femoral cutaneous nerve, and fascia lata, are located nearby.

  9. Analysis of Air Cargo Transfer Service Chain at Pudong International Airport%浦东国际机场货运中转服务链分析

    Institute of Scientific and Technical Information of China (English)

    刘锐; 崔诚靓; 陈川

    2015-01-01

    Air cargo transfer involves several participants in its operation process, including ship pers, freight forwarders, airport cargo terminal, airlines, customs and other regulatory agencies. All of the related participants constitute the entire service chain of air cargo transfer, making the air transport continuous and convenient. Based on field research into the related enterprises, this study summarizes the developing situation about the air cargo transfer at Pudong International Airport as well as the related appeals proposed by the relevant partici pants, points out the problems at Pudong International Airport and presents some suggestions from the perspec tive of service chain.%现代航空货物中转运输在其运营过程中涉及到许多参与方,包括货主、货代、机场货站、航空公司以及海关等监管机构,所有这一系列参与方构成了整个货运中转服务链条,维系着航空运输的连续性和快捷性. 在立足对浦东机场各个货运相关参与方的实地调研的基础上,通过收集整理国外枢纽机场和相关企业的资料,分析总结浦东机场各个参与方的发展现状,梳理了参与方对中转联程运输的相关诉求,指出了浦东机场货运中转服务链中所存在的相关问题,最后从服务链的角度提出改善浦东机场货运中转的建议.

  10. Trophic transfer and accumulation of TiO2 nanoparticles from clamworm (Perinereis aibuhitensis) to juvenile turbot (Scophthalmus maximus) along a marine benthic food chain.

    Science.gov (United States)

    Wang, Zhenyu; Yin, Liyun; Zhao, Jian; Xing, Baoshan

    2016-05-15

    In the present work, we investigated the potential benthic trophic transfer of TiO2 nanoparticles (NPs) from clamworm (Perinereis aibuhitensis) to juvenile turbot (Scophthalmus maximus) and their related distribution and toxicity. TiO2 NPs (at 10, 50 and 100 mg/L) could be taken up by clamworms, and mainly accumulated in the lower-digestive tract. TiO2 NPs were able to transfer from clamworms to juvenile turbots. The accumulation of TiO2 NPs in juvenile turbots increased with increasing Ti contents in clamworms during the dietary exposure, however, no biomagnification (BMFs, 0.30-0.33) of TiO2 NPs was observed. For both dietary and waterborne exposure, accumulation of TiO2 NPs was higher in the gill, intestine and stomach of juvenile turbot, following by skin, liver, and muscle. During dietary exposure at Day 20, the growth of turbots was reduced, and abnormal symptoms of liver and spleen were detected. Moreover, both dietary (50 and 100 mg/L TiO2 NPs-treated clamworms) and waterborne (100 mg/L TiO2 NPs) exposures led to significantly lower protein and higher lipid contents, suggesting the nutrition quality reduction of turbots. The findings from this work highlighted the trophic transfer of TiO2 NPs in marine benthic food chain, leading to the potential negative impact on marine aquaculture and food quality. PMID:27010785

  11. Design of ownership transfer protocol in supply chains%基于供应链环境的所有权转移方案设计

    Institute of Scientific and Technical Information of China (English)

    苑津莎; 陈琳; 张路路

    2016-01-01

    Concerning the products in different supply chain environments in the process of production and sale,a solution applied to ownership transfer of the various stages of the supply chain was proposed.In the production stage,the product was in a closed system.To guarantee the label and the product not being tracked,an authentication protocol based on pseudo ID was adopted. In the sale stage,to share products and related information of the Internet environment,a mutual authentication protocol based on asymmetric keys and Hash function was adopted.The corresponding methods of ownership transfer and updating label certifi-cation number were executed after authentication.According to the requirements of the business,the former owner of one party put forward and completed the transformation of ownership,such not only could realize the transfer of the ownership and infor-mation,but also ensure the supply chain visibility.%针对产品在生产、销售过程中所处供应链环境不同的特点,提出一种适用于供应链各个阶段的所有权转移方案。在生产阶段,产品处于内部封闭系统中,为保证标签及产品不被跟踪,采用基于伪 ID 的物联网安全认证方法认证标签;在销售阶段,产品及相关信息在互联网环境中,为更好实现资源共享,采用基于非对称密钥和Hash函数的RFID双向认证协议认证标签。认证成功后执行对应的所有权转移方法及标签认证数字更新方法。根据业务的要求,所有权转移由原所有者一方提出并完成所有权的转换,实现了所有权和信息的安全转移,保证了供应链的可视性。

  12. Anomalous charge and negative-charge-transfer insulating state in cuprate chain-compound KCuO_2

    OpenAIRE

    Choudhury, D.; Rivero, P.; Meyers, D.; Liu, X.; Cao, Y; Middey, S.; Whitaker, M. J.; Barraza-Lopez, S.; Freeland, J. W.; Greenblatt, M.; Chakhalian, J.

    2015-01-01

    Using a combination of X-ray absorption spectroscopy experiments with first principle calculations, we demonstrate that insulating KCuO_2 contains Cu in an unusually-high formal-3+ valence state, the ligand-to-metal (O to Cu) charge transfer energy is intriguingly negative (Delta~ -1.5 eV) and has a dominant (~60%) ligand-hole character in the ground state akin to the high Tc cuprate Zhang-Rice state. Unlike most other formal Cu^{3+} compounds, the Cu 2p XAS spectra of KCuO_2 exhibits pronoun...

  13. “土地流转”政策下农产品供应链的重构%Land Transfer and the Reconstruction of Agricultural Supply Chain

    Institute of Scientific and Technical Information of China (English)

    江许胜

    2012-01-01

    With the popularization of local land transfer, the level of agricultural industrialization has been gradually improved , agricultural logistics has an unprecedented development. But the traditional competition still remains among all the main logistics operators due to the lack of appropriate mechanism of convergence of profit, which leads to the high cost of logistics operation. In the prliminary study, the research group analyzed opportunities and challenges of agricultural logistics development on the basis of the land transfer, and now proposes constructing the agricultural supply chain to manage logistics with the management idea of supply chain so as to explore a new way for the development of the agricultural logistics.%随着各地土地流转的推广普及,农业产业化水平不断提高,农业物流得到了前所未有的发展,但各物流经营主体之间仍保持着传统的竞争关系,缺乏适宜的利益衔接机制,物流运作成本居高不下。在前期研究中,课题组分析了土地流转对农业物流发展的机遇和挑战,在此基础之上,提出了构建新型农产品供应链的想法,用供应链管理的思想管理物流,力求为农产品物流的发展探寻一个新途径。

  14. Fe2+-Ti4+ vs. Fe2+-Fe3+ charge-transfer and short-range order in single chains of face-sharing octahedra: ellenbergerite and dumortierite

    Science.gov (United States)

    Chopin, C.; Langer, K.; Khomenko, V.

    2009-04-01

    In zoned pyrope megacrysts from the Dora-Maira UHP terrane, new, dark-violet colour varieties of the hexagonal, high-pressure silicate ellenbergerite extend the range of known Fe contents for this mineral from 0-0.1 to 0-0.4 atom pfu, for Ti contents commonly in the range 0.2-0.4 pfu. The new varieties show an extremely intense pleochroism, colourless for E perpendicular to c to deep Prussian blue for E//c, as compared to colourless to lilac or reddish purple for classical Fe-poor ellenbergerite. These features were the incentive for an electronic absorption spectroscopic study and a reappraisal of the interpretation of the charge transfers (CT), colour and ordering schemes in this group and the structurally related borosilicate dumortierite. Both structures are characterized by the presence of infinite single chains of face-sharing, partly vacant octahedra along the 6-fold screw axis and pseudo-hexad axis, respectively, in which the Fe and Ti atoms are partitioned. In the spectra of Fe-poor ellenbergerite, the presence of a single Fe2+-Ti4+ CT band near 19000 cm˘1 was taken as evidence for complete short-range ordering of Mg(Fe), Ti and vacancies in the octahedral single chain [1]. The E//c spectra of Fe-rich ellenbergerite show the same absorption band near 19000 cm˘1 but consistently flanked by another CT band near 14000 cm˘1 , the intensity of which increases with total Fe content. The latter is similar to the 12400 cm˘1 CT band observed as the single feature in E//c spectra of the isotructural (Ti-free and Fe-bearing) phosphoellenbergerite, and clearly assigned to Fe2+-Fe3+ CT in the octahedral single chain [1]. The same colour pattern occurs in the dumortierite group, with red Fe-poor, Ti-rich crystals showing a single CT band near 20000 cm˘1, blue Ti-poor crystals showing a single CT band near 16500 cm˘1, and violet Fe- and Ti-rich crystals showing a combination of the two bands [2]. In the light of the new data, we reinterpret the dumortierite colour

  15. Food-chain transfer of zinc from contaminated Urtica dioica and Acer pseudoplatanus L. to the aphids Microlophium carnosum and Drepanosiphum platanoidis Schrank

    Energy Technology Data Exchange (ETDEWEB)

    Sinnett, Danielle, E-mail: danielle.sinnett@forestry.gsi.gov.u [Centre for Forestry and Climate Change, Forest Research, Alice Holt Lodge, Farnham, Surrey GU10 4LH (United Kingdom); Department of Soil Science, School of Human and Environmental Sciences, University of Reading, Whiteknights, Reading RG6 6DW (United Kingdom); Hutchings, Tony R., E-mail: tony.hutchings@forestry.gsi.gov.u [Centre for Forestry and Climate Change, Forest Research, Alice Holt Lodge, Farnham, Surrey GU10 4LH (United Kingdom); Hodson, Mark E., E-mail: m.e.hodson@reading.ac.u [Department of Soil Science, School of Human and Environmental Sciences, University of Reading, Whiteknights, Reading RG6 6DW (United Kingdom)

    2010-01-15

    This study examines the food-chain transfer of Zn from two plant species, Urtica dioica (stinging nettle) and Acer pseudoplatanus (sycamore maple), into their corresponding aphid species, Microlophium carnosum and Drepanosiphum platanoidis. The plants were grown in a hydroponic system using solutions with increasing concentrations of Zn from 0.02 to 41.9 mg Zn/l. Above-ground tissue concentrations in U. dioica and M. carnosum increased with increasing Zn exposure (p < 0.001). Zn concentrations in A. pseudoplatanus also increased with solution concentration from the control to the 9.8 mg Zn/l solution, above which concentrations remained constant. Zn concentrations in both D. platanoidis and the phloem tissue of A. pseudoplatanus were not affected by the Zn concentration in the watering solution. It appears that A. pseudoplatanus was able to limit Zn transport in the phloem, resulting in constant Zn exposure to the aphids. Zn concentrations in D. platanoidis were around three times those in M. carnosum. - Concentrations of Zn in two aphid species are dependant on species and exposure.

  16. Asymmetric Synthesis and Binding Study of New Long-Chain HPA-12 Analogues as Potent Ligands of the Ceramide Transfer Protein CERT.

    Science.gov (United States)

    Ďuriš, Andrej; Daïch, Adam; Santos, Cécile; Fleury, Laurence; Ausseil, Frédéric; Rodriguez, Frédéric; Ballereau, Stéphanie; Génisson, Yves; Berkeš, Dušan

    2016-05-01

    A series of 12 analogues of the Cer transfer protein (CERT) antagonist HPA-12 with long aliphatic chains were prepared as their (1R,3S)-syn and (1R,3R)-anti stereoisomers from pivotal chiral oxoamino acids. The enantioselective access to these intermediates as well as their ensuing transformation relied on a practical crystallization-induced asymmetric transformation (CIAT) process. Sonogashira coupling followed by triple bond reduction and thiophene ring hydrodesulfurization (HDS) into the corresponding alkane moieties was then implemented to complete the synthetic routes delivering the targeted HPA-12 analogues in concise 4- to 6-step reaction sequences. Ten compounds were evaluated regarding their ability to bind to the CERT START domain by using the recently developed time-resolved FRET-based homogeneous (HTR-FRET) binding assay. The introduction of a lipophilic appendage on the phenyl moiety led to an overall 10- to 1000-fold enhancement of the protein binding, with the highest effect being observed for a n-hexyl residue in the meta position. The importance of the phenyl ring for the activity was indicated by the reduced potency of the 3-deoxyphytoceramide aliphatic analogues. The 1,3-syn stereoisomers were systematically more potent than their 1,3-anti analogues. In silico studies were used to rationalized these trends, leading to a model of protein recognition coherent with the stronger binding of (1R,3S)-syn HPAs.

  17. 100-N Area Strontium-90 Treatability Demonstration Project: Food Chain Transfer Studies for Phytoremediation Along the 100-N Columbia River Riparian Zone

    Energy Technology Data Exchange (ETDEWEB)

    Fellows, Robert J.; Fruchter, Jonathan S.; Driver, Crystal J.

    2009-04-01

    Strontium-90 (90Sr) exceeds the U.S. Environmental Protection Agency’s drinking water standards for groundwater (8 picocuries/L) by as much as a factor of 1000 at several locations within the Hanford 100-N Area and along the 100-N Area Columbia River shoreline). Phytoextraction, a managed remediation technology in which plants or integrated plant/rhizosphere systems are employed to phytoextract and/or sequester 90Sr, is being considered as a potential remediation system along the riparian zone of the Columbia River as part of a treatment train that includes an apatite barrier to immobilize groundwater transport of 90Sr. Phytoextraction would employ coyote willow (Salix exigua) to extract 90Sr from the vadose zone soil and aquifer sediments (phytoextraction) and filter 90Sr (rhizofiltration) from the shallow groundwater along the riparian zone of the Columbia River. The stem and foliage of coyote willows accumulating 90Sr may present not only a mechanism to remove the contaminant but also can be viewed as a source of nutrition for natural herbivores, therefore becoming a potential pathway for the isotope to enter the riparian food chain. Engineered barriers such as large and small animal fencing constructed around the field plot will control the intrusion of deer, rodents, birds, and humans. These efforts, however, will have limited effect on mobile phytophagous insects. Therefore, this study was undertaken to determine the potential for food chain transfer by insects prior to placement of the remediation technology at 100-N. Insect types include direct consumers of the sap or liquid content of the plants vascular system (xylem and phloem) by aphids as well as those that would directly consume the plant foliage such as the larvae (caterpillars) of Lepidoptera species. Heavy infestations of aphids feeding on the stems and leaves of willows growing in 90Sr-contaminated soil can accumulate a small amount (~0.15 ± 0.06%) of the total label removed from the soil by

  18. 基于QFD的供应链质量风险传递模型研究%The Transfer Model Investigation of QFD-based Supply Chain Quality Risk

    Institute of Scientific and Technical Information of China (English)

    颜忠娥

    2013-01-01

    The product quality risk have progressively transfer and downward expanding effect in supply chain environment. When a upstream enterprise in supply chain have quality fluctuations, the quality risk is presented as the deviations of downstream customer satisfaction directly. How to analyze and predict the transfer model and consequences of the customer satisfaction deviations induced by quality risk become the main content of the risk management of quality risk in the supply chain. The formation mechanism of supply chain quality risk is investigated in this paper. The model of quality of the supply chain based on quality function is estab-lished, and the quantitative analysis model of the supply chain quality risk transfer process is proposed.%  供应链环境下的产品质量风险具有逐级传递并向下扩大的趋势效应,当供应链上某节点企业发生质量波动时,质量风险的直接表现形式为下游顾客需求满意度发生偏差。分析与预测因质量风险所导致的顾客满意度偏差在供应链中的传递及影响后果,成为供应链质量风险管理研究的主要内容之一。基于此,分析了供应链质量风险形成机理,建立了基于质量功能展开的质量供需链模型,提出了供应链质量风险传递的定量分析模型。

  19. Electrospun regenerated cellulose nanofibrous membranes surface-grafted with polymer chains/brushes via the atom transfer radical polymerization method for catalase immobilization.

    Science.gov (United States)

    Feng, Quan; Hou, Dayin; Zhao, Yong; Xu, Tao; Menkhaus, Todd J; Fong, Hao

    2014-12-10

    In this study, an electrospun regenerated cellulose (RC) nanofibrous membrane with fiber diameters of ∼200-400 nm was prepared first; subsequently, 2-hydroxyethyl methacrylate (HEMA), 2-dimethylaminoethyl methacrylate (DMAEMA), and acrylic acid (AA) were selected as the monomers for surface grafting of polymer chains/brushes via the atom transfer radical polymerization (ATRP) method. Thereafter, four nanofibrous membranes (i.e., RC, RC-poly(HEMA), RC-poly(DMAEMA), and RC-poly(AA)) were explored as innovative supports for immobilization of an enzyme of bovine liver catalase (CAT). The amount/capacity, activity, stability, and reusability of immobilized catalase were evaluated, and the kinetic parameters (Vmax and Km) for immobilized and free catalase were determined. The results indicated that the respective amounts/capacities of immobilized catalase on RC-poly(HEMA) and RC-poly(DMAEMA) nanofibrous membranes reached 78 ± 3.5 and 67 ± 2.7 mg g(-1), which were considerably higher than the previously reported values. Meanwhile, compared to that of free CAT (i.e., 18 days), the half-life periods of RC-CAT, RC-poly(HEMA)-CAT, RC-poly(DMAEMA)-CAT, and RC-poly(AA)-CAT were 49, 58, 56, and 60 days, respectively, indicating that the storage stability of immobilized catalase was also significantly improved. Furthermore, the immobilized catalase exhibited substantially higher resistance to temperature variation (tested from 5 to 70 °C) and lower degree of sensitivity to pH value (tested from 4.0 and 10.0) than the free catalase. In particular, according to the kinetic parameters of Vmax and Km, the nanofibrous membranes of RC-poly(HEMA) (i.e., 5102 μmol mg(-1) min(-1) and 44.89 mM) and RC-poly(DMAEMA) (i.e., 4651 μmol mg(-1) min(-1) and 46.98 mM) had the most satisfactory biocompatibility with immobilized catalase. It was therefore concluded that the electrospun RC nanofibrous membranes surface-grafted with 3-dimensional nanolayers of polymer chains/brushes would be

  20. ALTERNATE FOOD-CHAIN TRANSFER OF THE TOXIN LINKED TO AVIAN VACUOLAR MYELINOPATHY AND IMPLICATIONS FOR THE ENDANGERED FLORIDA SNAIL KITE (ROSTRHAMUS SOCIABILIS).

    Science.gov (United States)

    Dodd, Shelley R; Haynie, Rebecca S; Williams, Susan M; Wilde, Susan B

    2016-04-28

    Avian vacuolar myelinopathy (AVM) is a neurologic disease causing recurrent mortality of Bald Eagles ( Haliaeetus leucocephalus ) and American Coots ( Fulica americana ) at reservoirs and small impoundments in the southern US. Since 1994, AVM is considered the cause of death for over 170 Bald Eagles and thousands of American Coots and other species of wild birds. Previous studies link the disease to an uncharacterized toxin produced by a recently described cyanobacterium, Aetokthonos hydrillicola gen. et sp. nov. that grows epiphytically on submerged aquatic vegetation (SAV). The toxin accumulates, likely in the gastrointestinal tract of waterbirds that consume SAV, and birds of prey are exposed when feeding on the moribund waterbirds. Aetokthonos hydrillicola has been identified in all reservoirs where AVM deaths have occurred and was identified growing abundantly on an exotic SAV hydrilla ( Hydrilla verticillata ) in Lake Tohopekaliga (Toho) in central Florida. Toho supports a breeding population of a federally endangered raptor, the Florida Snail Kite ( Rostrhamus sociabilis ) and a dense infestation of an exotic herbivorous aquatic snail, the island applesnail ( Pomacea maculata ), a primary source of food for resident Snail Kites. We investigated the potential for transmission in a new food chain and, in laboratory feeding trials, confirmed that the AVM toxin was present in the hydrilla/A. hydrillicola matrix collected from Toho. Additionally, laboratory birds that were fed apple snails feeding on hydrilla/A. hydrillicola material from a confirmed AVM site displayed clinical signs (3/5), and all five developed brain lesions unique to AVM. This documentation of AVM toxin in central Florida and the demonstration of AVM toxin transfer through invertebrates indicate a significant risk to the already diminished population of endangered Snail Kites. PMID:26981686

  1. Amphiphilic block copolymers bearing six-membered ortho ester ring in side chains as potential drug carriers: synthesis, characterization, and in vivo toxicity evaluation.

    Science.gov (United States)

    Luo, Shi; Tao, Yangyang; Tang, Rupei; Wang, Rui; Ji, Weihang; Wang, Chun; Zhao, Youliang

    2014-07-01

    A new type of amphiphilic block copolymers, poly(ethylene glycol)-block-poly(2-methyl-acrylicacid 2-methoxy-5-methyl-[1,3]dioxin-5-ylmethyl ester) (PEG-b-PMME), bearing acid-labile six-membered ortho ester rings in side chains was synthesized by reversible addition-fragmentation chain-transfer polymerization, and the influence of chain length of the hydrophobic PMME block on micelle properties was investigated. The PEG-b-PMME micelles were stable in aqueous buffer at physiological pH with a low critical micelle concentration. Nile Red as a model drug was encapsulated into the micelles to explore the release profiles. The Nile Red-loaded polymeric micelles showed rapid release of Nile Red in weakly acidic environments (pH 5) but slow release under physiological condition (pH 7.4), due to different hydrolysis rate of ortho ester side chains of PEG-b-PMME. The Paclitaxel (PTX)-loaded micelles retained potency in killing lung cancer cells (A549), compared with the free PTX. No obvious toxicity was found in vitro and in vivo after intraperitoneal injection of the micelles, which confirms that the PEG-b-PMME micelles with unique acid-labile characteristic have great potential as nano-scaled carriers for drug delivery.

  2. Understanding transferable supply chain lessons and practices to a "high-tech" industry using guidelines from a primary sector industry: a case study in the food industry supply chain.

    Science.gov (United States)

    Coronado Mondragon, Adrian E; Coronado Mondragon, Christian E; Coronado, Etienne S

    2015-01-01

    Flexibility and innovation at creating shapes, adapting processes, and modifying materials characterize composites materials, a "high-tech" industry. However, the absence of standard manufacturing processes and the selection of materials with defined properties hinder the configuration of the composites materials supply chain. An interesting alternative for a "high-tech" industry such as composite materials would be to review supply chain lessons and practices in "low-tech" industries such as food. The main motivation of this study is to identify lessons and practices that comprise innovations in the supply chain of a firm in a perceived "low-tech" industry that can be used to provide guidelines in the design of the supply chain of a "high-tech" industry, in this case composite materials. This work uses the case study/site visit with analogy methodology to collect data from a Spanish leading producer of fresh fruit juice which is sold in major European markets and makes use of a cold chain. The study highlights supply base management and visibility/traceability as two elements of the supply chain in a "low-tech" industry that can provide guidelines that can be used in the configuration of the supply chain of the composite materials industry.

  3. Surface functionalization of quantum dots with fine-structured pH-sensitive phospholipid polymer chains.

    Science.gov (United States)

    Liu, Yihua; Inoue, Yuuki; Ishihara, Kazuhiko

    2015-11-01

    To add novel functionality to quantum dots (QDs), we synthesized water-soluble and pH-responsive block-type polymers by reversible addition-fragmentation chain transfer (RAFT) polymerization. The polymers were composed of cytocompatible 2-methacryloyloxyethyl phosphorylcholine (MPC) polymer segments, which contain a small fraction of active ester groups and can be used to conjugate biologically active compounds to the polymer, and pH-responsive poly(2-(N,N-diethylamino) ethyl methacrylate (DEAEMA)) segments. One terminal of the polymer chain had a hydrophobic alkyl group that originated from the RAFT initiator. This hydrophobic group can bind to the hydrophobic layer on the QD surface. A fluorescent dye was conjugated to the polymer chains via the active ester group. The block-type polymers have an amphiphilic nature in aqueous medium. The polymers were thus easily bound to the QD surface upon evaporation of the solvent from a solution containing the block-type polymer and QDs, yielding QD/fluorescence dye-conjugated polymer hybrid nanoparticles. Fluorescence resonance energy transfer (FRET) between the QDs (donors) and the fluorescent dye molecules (acceptors) was used to obtain information on the conformational dynamics of the immobilized polymers. Higher FRET efficiency of the QD/fluorescent dye-conjugated polymer hybrid nanoparticles was observed at pH 7.4 as compared to pH 5.0 due to a stretching-shrinking conformational motion of the poly(DEAEMA) segments in response to changes in pH. We concluded that the block-type MPC polymer-modified nanoparticles could be used to evaluate the pH of cells via FRET fluorescence based on the cytocompatibility of the MPC polymer.

  4. A polymorphic variant in the human electron transfer flavoprotein alpha-chain (alpha-T171) displays decreased thermal stability and is overrepresented in very-long-chain acyl-CoA dehydrogenase-deficient patients with mild childhood presentation

    DEFF Research Database (Denmark)

    Bross, P; Pedersen, P; Nyholm, M;

    1999-01-01

    , whereas the two variants of the beta-M/T154 polymorphism did not differ. We wished to test the hypothesis that these polymorphisms might constitute susceptibility factors and therefore determined their allele and genotype frequencies in (i) control individuals, (ii) medium-chain acyl-CoA dehydrogenase......-deficient patients homozygous for the K304E mutation (MCAD E304), (iii) a group of patients with elevated urinary excretion of ethylmalonic acid (EMA) possibly due to decreased short-chain acyl-CoA dehydrogenase activity, and (iv) in patients with proven deficiency of very-long-chain acyl-CoA dehydrogenase (VLCAD......). No significant overrepresentations or underrepresentations were found in the first two patient groups, suggesting that the polymorphisms studied are not significant susceptibility factors in either the MCAD E304 or the EMA patient group. However, in the VLCAD deficient patients the alpha-T171 variant (decreased...

  5. Transfer of noncovalent chiral information along an optically inactive helical peptide chain: allosteric control of asymmetry of the C-terminal site by external molecule that binds to the N-terminal site.

    Science.gov (United States)

    Ousaka, Naoki; Inai, Yoshihito

    2009-02-20

    This study aims at demonstrating end-to-end transfer of noncovalent chiral information along a peptide chain. The domino-type induction of helical sense is proven by using achiral peptides 1-m of bis-chromophoric sequence with different chain lengths: H-(Aib-Delta(Z)Phe)(m)-(Aib-Delta(Z)Bip)(2)-Aib-OCH(3) [m = 2, 4, and 6; Aib = alpha-aminoisobutyric acid; Delta(Z)Phe = (Z)-alpha,beta-didehydrophenylalanine; Delta(Z)Bip = (Z)-beta-(4,4'-biphenyl)-alpha,beta-didehydroalanine]. They all showed the tendency to adopt a 3(10)-helix. Whereas peptide 1-m originally shows no circular dichroism (CD) signals, marked CD signals were induced at around 270-320 nm based on both the beta-aryl didehydroresidues by chiral Boc-proline (Boc = tert-butoxycarbonyl). The observed CD spectra were interpreted on the basis of the exciton chirality method and theoretical CD simulation of several helical conformations that were energy-minimized. The experimental and theoretical CD analysis reveals that Boc-l-proline induces the preference for a right-handed helicity in the whole chain of 1-m. Such noncovalent chiral induction was not observed in the corresponding N-terminally protected 1-m. Obviously, helicity induction in 1-m originates from the binding of Boc-proline to the N-terminal site. In the 17-mer (1-6), the information of helix sense reaches the 16th residue from the N-terminus. We have monitored precise transfer of noncovalent chiral stimulus along a helical peptide chain. The present study also proposes a primitive allosteric model of a single protein-mimicking backbone. Here chiral molecule binding the N-terminal site of 1-6 controls the chiroptical signals and helical sense of the C-terminal site about 30 A away.

  6. Bcl-1 gene rearrangements in mantle cell lymphoma : A comprehensive analysis of 118 cases, including B-5-fixed tissue, by polymerase chain reaction and southern transfer analysis

    NARCIS (Netherlands)

    Chibbar, R; Leung, K; McCormick, S; Ritzkalla, K; Strickler, J; Staggs, R; Poppema, S; Brunning, RD; McGlennen, RC

    1998-01-01

    We evaluated 118 cases of mantle cell lymphoma by polymerase chain reaction (PCR) for the major translocation cluster (MIG) region and another breakpoint corresponding to probe p94(PS), located 24 kb telomeric to the MTC locus on chromosome 11. The specimens included 64 frozen, 19 formalin-fixed, an

  7. Electron Transfer of Myoglobin Immobilized in Au Electrodes Modified with a RAFT PMMA-Block-PDMAEMA Polymer

    Directory of Open Access Journals (Sweden)

    Carla N. Toledo

    2014-01-01

    Full Text Available Myoglobin was immobilized with poly(methyl methacrylate-block-poly[(2-dimethylaminoethyl methacrylate]PMMA-block-PDMAEMA polymer synthesized by reversible addition-fragmentation chain transfer technique (RAFT. Cyclic voltammograms gave direct and slow quasireversible heterogeneous electron transfer kinetics between Mb-PMMA-block-PDMAEMA modified electrode and the redox center of the protein. The values for electron rate constant (Ks and transfer coefficient (α were 0.055±0.01·s−1 and 0.81±0.08, respectively. The reduction potential determined as a function of temperature (293–328 K revealed a value of reaction center entropy of ΔS0 of 351.3±0.0002 J·mol−1·K−1 and enthalpy change of -76.8±0.1 kJ·mol−1, suggesting solvent effects and charge ionization atmosphere involved in the reaction parallel to hydrophobic interactions with the copolymer. The immobilized protein also exhibits an electrocatalytical response to reduction of hydrogen peroxide, with an apparent Km of 114.7±58.7 μM. The overall results substantiate the design and use of RAFT polymers towards the development of third-generation biosensors.

  8. Effects of medium-chain fatty acids and oleic acid on blood lipids, lipoproteins, glucose, insulin, and lipid transfer protein activities

    DEFF Research Database (Denmark)

    Tholstrup, T.; Ehnholm, C.; Jauhiainen, M.;

    2004-01-01

    design, 17 healthy young men replaced part of their habitual dietary fat intake with 70 g MCTs (66% 8:0 and 34% 10:0) or high-oleic sunflower oil (89.4% 18:1). Each intervention period lasted 21 d, and the 2 periods were separated by a washout period of 2 wk. Blood samples were taken before and after...... the intervention periods. Results: Compared with the intake of high-oleic sunflower oil, MCT intake resulted in 11% higher plasma total cholesterol (P = 0.0005), 12% higher LDL cholesterol (P = 0.0001), 32% higher VLDL cholesterol (P = 0.080), a 12% higher ratio of LDL to HDL cholesterol (P = 0.002), 22% higher......Background: Dietary medium-chain fatty acids (MCFAs) are of nutritional interest because they are more easily absorbed from dietary medium-chain triacylglycerols (MCTs) than are long-chain fatty acids from, for example, vegetable oils. It has generally been claimed that MCFAs do not increase plasma...

  9. Study of the Chain Transfer Reaction of 3-Mercaptohexanol in the Styrene Polymerization%3-巯基己醇在苯乙烯聚合体系中的链转移反应行为

    Institute of Scientific and Technical Information of China (English)

    张薇; 黄文艳; 李少杰; 薛小强; 蒋必彪

    2011-01-01

    The polymerization of styrene was carried out in the presence of 3 - mercaptohexanol at different temperature with AIBN as the initiator and toluene as the internal standard. The chain transfer constant of 3 - mercaptohexanol under the experimental condition was obtained by the Mayo equation. It is 3. 99, 3. 58 and 2. 24 at the polymerization temperature of 60 ℃ , 70 ℃ and 80 ℃ respectively. As the temperature increased, the chain transfer constant of 3 - mercaptohexanol decreased. Further research showed that; under the polymerization condition, the products with very low molecular weight were formed from the 3-mercaptohexanol transferring to styrene radical. The dimer and trimer of these products were obtained by high performance liquid chromatography and confirmed by proton nuclear magnetic resonance (1H NMR) and liquid chromatography-mass spectrometry (LC - MS). The productivity of these products increased significantly as the reaction temperature increased. Therefore, the obtained chain transfer constant is only the apparent value because of the formation of the molecules with very low molecular weight.%以偶氯二异丁腈(AIBN)为引发剂,甲苯为内标,3-巯基己醇为链转移剂进行苯乙烯(St)聚合.根据Mayo等式,求出了60℃,70℃和80℃下的链转移常数,分别为3.99,3.58和2.24,表明链转移常数随着温度的升高而减小.采用制备色谱分离得到了聚合初期的产物,并且由核磁共振(1H NMR)和液-质联用(LC-MS)确证了生成的小分子产物的结构.定量分析结果表明:在相同的巯基醇转化率下,相对分子质量低的产物的生成量随反应温度的升高而显著增加,以聚合物相对分子质量为基础计算得到的表观链转移常数则变小.

  10. Calibration of environmental radionuclide transfer models using a Bayesian approach with Markov chain Monte Carlo simulations and model comparisons - Calibration of radionuclides transfer models in the environment using a Bayesian approach with Markov chain Monte Carlo simulation and comparison of models

    Energy Technology Data Exchange (ETDEWEB)

    Nicoulaud-Gouin, V.; Giacalone, M.; Gonze, M.A. [Institut de Radioprotection et de Surete Nucleaire-PRP-ENV/SERIS/LM2E (France); Martin-Garin, A.; Garcia-Sanchez, L. [IRSN-PRP-ENV/SERIS/L2BT (France)

    2014-07-01

    Calibration of transfer models according to observation data is a challenge, especially if parameters uncertainty is required, and if competing models should be decided between them. Generally two main calibration methods are used: The frequentist approach in which the unknown parameter of interest is supposed fixed and its estimation is based on the data only. In this category, least squared method has many restrictions in nonlinear models and competing models need to be nested in order to be compared. The bayesian inference in which the unknown parameter of interest is supposed random and its estimation is based on the data and on prior information. Compared to frequentist method, it provides probability density functions and therefore pointwise estimation with credible intervals. However, in practical cases, Bayesian inference is a complex problem of numerical integration, which explains its low use in operational modeling including radioecology. This study aims to illustrate the interest and feasibility of Bayesian approach in radioecology particularly in the case of ordinary differential equations with non-constant coefficients models, which cover most radiological risk assessment models, notably those implemented in the Symbiose platform (Gonze et al, 2010). Markov Chain Monte Carlo (MCMC) method (Metropolis et al., 1953) was used because the posterior expectations are intractable integrals. The invariant distribution of the parameters was performed by the metropolis-Hasting algorithm (Hastings, 1970). GNU-MCSim software (Bois and Maszle, 2011) a bayesian hierarchical framework, was used to deal with nonlinear differential models. Two case studies including this type of model were investigated: An Equilibrium Kinetic sorption model (EK) (e.g. van Genuchten et al, 1974), with experimental data concerning {sup 137}Cs and {sup 85}Sr sorption and desorption in different soils studied in stirred flow-through reactors. This model, generalizing the K{sub d} approach

  11. Enhanced binding capacity of boronate affinity adsorbent via surface modification of silica by combination of atom transfer radical polymerization and chain-end functionalization for high-efficiency enrichment of cis-diol molecules

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Wei; He, Maofang; Wang, Chaozhan; Wei, Yinmao, E-mail: ymwei@nwu.edu.cn

    2015-07-30

    Boronate affinity materials have been widely used for specific separation and preconcentration of cis-diol molecules, but most do not have sufficient capacity due to limited binding sites on the material surface. In this work, we prepared a phenylboronic acid-functionalized adsorbent with a high binding capacity via the combination of surface-initiated atom transfer radical polymerization (SI-ATRP) and chain-end functionalization. With this method, the terminal chlorides of the polymer chains were used fully, and the proposed adsorbent contains dense boronic acid polymers chain with boronic acid on the chain end. Consequently, the proposed adsorbent possesses excellent selectivity and a high binding capacity of 513.6 μmol g{sup −1} for catechol and 736.8 μmol g{sup −1} for fructose, which are much higher than those of other reported adsorbents. The dispersed solid-phase extraction (dSPE) based on the prepared adsorbent was used for extraction of three cis-diol drugs (i.e., epinephrine, isoprenaline and caffeic acid isopropyl ester) from plasma; the eluates were analyzed by HPLC-UV. The reduced amount of adsorbent (i.e., 2.0 mg) could still eliminate interferences efficiently and yielded a recovery range of 85.6–101.1% with relative standard deviations ranging from 2.5 to 9.7% (n = 5). The results indicated that the proposed strategy could serve as a promising alternative to increase the density of surface functional groups on the adsorbent; thus, the prepared adsorbent has the potential to effectively enrich cis-diol substances in real samples. - Highlights: • Boronate adsorbent is prepared via ATRP and chain-end functionalization. • The adsorbent has quite high binding capacity for cis-diols. • Binding capacity is easily manipulated by ATRP condition. • Chain-end functionalization can improve binding capacity significantly. • Reduced adsorbent is consumed in dispersed solid-phase extraction of cis-diols.

  12. Characterization of a unique [FeS] cluster in the electron transfer chain of the oxygen tolerant [NiFe] hydrogenase from Aquifex aeolicus

    OpenAIRE

    Pandelia, Maria-Eirini; Nitschke, Wolfgang; Infossi, Pascale; Giudici-Orticoni, Marie-Thérèse; Bill, Eckhard; Lubitz, Wolfgang

    2011-01-01

    Iron-sulfur clusters are versatile electron transfer cofactors, ubiquitous in metalloenzymes such as hydrogenases. In the oxygen-tolerant Hydrogenase I from Aquifex aeolicus such electron “wires” form a relay to a diheme cytb, an integral part of a respiration pathway for the reduction of O2 to water. Amino acid sequence comparison with oxygen-sensitive hydrogenases showed conserved binding motifs for three iron-sulfur clusters, the nature and properties of which were unknown so far. Electron...

  13. Unwrapping Chains

    CERN Document Server

    Cambou, A D; Hamm, E; Hanna, J A; Menon, N; Santangelo, C D; Walsh, L

    2012-01-01

    A loop of chain can move along its own tangents, maintaining a steady shape. An open-ended chain undergoing a nontrivial motion must change its shape. One consequence is that chains pulled around objects will fail to follow the contours of the objects, unwrapping themselves instead. This short note accompanies a fluid dynamics video submission (83068) to the APS DFD Gallery of Fluid Motion 2012.

  14. Comparison of transfer and effects of Cd on rats exposed in a short experimental snail-rat food chain or to CdCl2 dosed food.

    Science.gov (United States)

    Hispard, F; de Vaufleury, A; Cosson, R P; Devaux, S; Scheifler, R; Coeurdassier, M; Gimbert, F; Martin, H; Richert, L; Berthelot, A; Badot, P-M

    2008-04-01

    Transfer and toxic effects of two cadmium (Cd) forms, inorganic (CdCl2 dosed rat food) or organic (contaminated snail-based rat food) were studied in Wistar rat. Cd concentrations in rat food were 0 and 2.5 microg Cd g(-1) for both inorganic and organic forms and a high concentration of 100 microg Cd g(-1) was also tested for the inorganic form. Rats were exposed for four weeks to contaminated food. Both forms of Cd were bioavailable to rats, with a percentage of transfer from food to rats of around 1% for all contaminated groups. Cd concentrations in rat tissues increased with increasing Cd concentrations in the food. Rats fed with organic form of Cd accumulated significantly more Cd in the main organ for Cd toxicity, the kidney, than those eating the inorganic form. Survival was not affected for any rat group but a decrease in growth and food consumption was observed for the inorganic form. As a defence system against Cd toxicity, rats increased their metallothionein (MT) synthesis at the highest Cd concentration in the target organs (kidney, liver and small intestine) and even did the same at low Cd concentrations (2.5 microg Cd g(-1)) in the kidney. At this low Cd concentration, MT induction was lower in the small intestine of rats ingesting organic Cd than those ingesting inorganic Cd. Bioavailability of organic and inorganic forms of Cd was similar, but subsequent Cd distribution within organs was different. This quantification of the trophic transfer of both inorganic and organic forms of a toxicant is a basis for a better assessment of the fate and effects of chemicals in food webs.

  15. Representation of a model of radionuclide transfer in food chains following deposition of strontium-90, cesium-137 and iodine-131 on areas for agricultural use

    International Nuclear Information System (INIS)

    The 'SINK' model (contaminants in food chains - FORTRAN 77) was used in an attempt to predict the amounts of radioactivity building up in animal and vegetable foods after one single deposition of Sr-90, Cs-137 and I-131. The model is described in detail. The input quantities include such factors as time-integrated concentration of activity in the air just above the ground, physicochemical form of the radionuclides, activity deposited with precipitation and amount of rain to fall in any particular case. The model was so designed as to take account of 18 different plants, 11 animal products and 14 kinds of processed nutrients. The radionuclide contents of vegetable foods were calculated with reference to the season of the year, at which deposition took place. The estimations of the activity concentrations in animal foods were in each case based on different fudder rations. (orig./HP)

  16. Transfer of heavy metals in the food chain earthworm Black-tailed godwit (Limosa limosa): Comparison of a polluted and a reference site in The Netherlands

    Energy Technology Data Exchange (ETDEWEB)

    Roodbergen, Maja [Department of Ecology and Environment, ALTERRA, PO Box 47, 6700 AA, Wageningen (Netherlands); Animal Ecology Group, Centre for Ecological and Evolutionary Studies, University of Groningen, Haren (Netherlands)], E-mail: maja.roodbergen@sovon.nl; Klok, Chris; Hout, Annemariet van der [Department of Ecology and Environment, ALTERRA, PO Box 47, 6700 AA, Wageningen (Netherlands)

    2008-12-01

    The Black-tailed godwit (Limosa limosa) is a migratory wader that favours wet meadows for breeding. The species has a Red List status in The Netherlands, as it strongly declined in numbers since the 1960s. Intensification of agriculture and land use change resulting in habitat loss are considered major causes of this decline. In some areas the breeding habitat is contaminated with heavy metals. Adult godwits mainly feed on earthworms in the breeding season, which are known to accumulate heavy metals from the soil. In this paper we investigate the transfer of heavy metals from the soil to the Black-tailed godwit, which may have an additive negative effect on the viability of local populations. We measured heavy metal concentrations in soil, earthworms, and godwit eggs and feathers at a polluted and a reference site. The results suggest that Lead, Mercury and Cadmium are transferred from the soil to godwits even though the species spends only a few months in the breeding area during the year.

  17. Transfer of heavy metals in the food chain earthworm Black-tailed godwit (Limosa limosa): Comparison of a polluted and a reference site in The Netherlands

    International Nuclear Information System (INIS)

    The Black-tailed godwit (Limosa limosa) is a migratory wader that favours wet meadows for breeding. The species has a Red List status in The Netherlands, as it strongly declined in numbers since the 1960s. Intensification of agriculture and land use change resulting in habitat loss are considered major causes of this decline. In some areas the breeding habitat is contaminated with heavy metals. Adult godwits mainly feed on earthworms in the breeding season, which are known to accumulate heavy metals from the soil. In this paper we investigate the transfer of heavy metals from the soil to the Black-tailed godwit, which may have an additive negative effect on the viability of local populations. We measured heavy metal concentrations in soil, earthworms, and godwit eggs and feathers at a polluted and a reference site. The results suggest that Lead, Mercury and Cadmium are transferred from the soil to godwits even though the species spends only a few months in the breeding area during the year

  18. Kinetics and mechanism of electron transfer reaction of single and double chain surfactant cobalt(III) complex by Fe2+ ions in liposome (dipalmitoylphosphotidylcholine) vesicles: effects of phase transition

    Science.gov (United States)

    Nagaraj, Karuppiah; Senthil Murugan, Krishnan; Thangamuniyandi, Pilavadi

    2015-05-01

    In this study, we report the kinetics of reduction reactions of single and double chain surfactant cobalt(III) complexes of octahedral geometry, cis-[Co(en)2(4AMP)(DA)](ClO4)3 and cis-[Co(dmp)2(C12H25NH2)2](ClO4)3 (en = ethylenediamine, dmp = 1,3-diaminopropane, 4AMP = 4-aminopropane, C12H25NH2 = dodecylamine) by Fe2+ ion in dipalmitoylphosphotidylcholine (DPPC) vesicles at different temperatures under pseudo first-order conditions. The kinetics of these reactions is followed by spectrophotometry method. The reactions are found to be second order and the electron transfer is postulated as outer sphere. The remarkable findings in the present investigation are that, below the phase transition temperature of DPPC, the rate decreases with an increase in the concentration of DPPC, while above the phase transition temperature the rate increases with an increase in the concentration of DPPC. The main driving force for this phenomenon is considered to be the intervesicular hydrophobic interaction between vesicles surface and hydrophobic part of the surfactant complexes. Besides, comparing the values of rate constants of these outer-sphere electron transfer reactions in the absence and in the presence of DPPC, the rate constant values in the presence of DPPC are always found to be greater than in the absence of DPPC. This is ascribed to the double hydrophobic fatty acid chain in the DPPC that gives the molecule an overall tubular shape due to the intervesicular hydrophobic interaction between vesicles surface and hydrophobic part of the surfactant complexes more suitable for vesicle aggregation which facilitates lower activation energy, and consequently higher rate is observed in the presence of DPPC. The activation parameters (ΔS# and ΔH#) of the reactions at different temperatures have been calculated which corroborate the kinetics of the reaction.

  19. Study of silver-110M transfer mechanisms in freshwater. Conceiving and utilization of an experimental model of ecosystem and of a mathematical model to simulate the radionuclide through a trophic chain

    International Nuclear Information System (INIS)

    Uptake and retention of 110mAg are quantified from laboratory studies carried out on an experimental freshwater ecosystem composed by two abiotic units, water and sediment, and by four trophic levels: primary producer (Scenedesmus obliquus), first order consumers (Daphnia magna, Gammarus pulex, Chrionomus sp.), second order consumer (Cyprinus carpio) and third order one (Salmo trutta). The chosen analytical process consists in expressing each transfer by a mathematical equation which formulation is based on a theoric analysis. Experiments allow to calibrate parameters of these equations for each unit of the food chain. All experimental data concerning 110mAg uptake emphasize the radioprotection implications of this radioelement, because of the high values of the estimated radioecological parameters. On the basis of the results obtained, a determinist mathematical model has been conceived to simulate the radionuclide distribution in the food chain as a function of a chronic or acute contamination mode. Its application gives the development with time of the mean 110mAg concentration values for each trophic level. The first approaches based on the analysis of the results of field studies, carried out on ecosystems affected by chronic pollution (Rhone river) or acute one (as a consequence of the Chernobyl accident), give to the model an important explicative and global predictive quality. The age of the fish, their dietary habits which vary according to the annual cycle of the prey species and with theirposition in the food chain, appear such as essential parameters. The trophic pathway is clearly predominant whatever the contamination mode and, explains, for acute exposure, why accumulation of 110mAg can be prolonged for a long time after the surrounding environment contamination

  20. Development and inter-laboratory transfer of a decaplex polymerase chain reaction assay combined with capillary electrophoresis for the simultaneous detection of ten food allergens.

    Science.gov (United States)

    Cheng, Fang; Wu, Jiajie; Zhang, Jin; Pan, Aihu; Quan, Sheng; Zhang, Dabing; Kim, HaeYeong; Li, Xiang; Zhou, Shan; Yang, Litao

    2016-05-15

    Food allergies cause health risks to susceptible consumers and regulations on labeling of food allergen contents have been implemented in many countries and regions. To achieve timely and accurate food allergen labeling, the development of fast and effective allergen detection methods is very important. Herein, a decaplex polymerase chain reaction (PCR) assay combined with capillary electrophoresis was developed to detect simultaneously 10 common food allergens from hazelnut, pistachio, oat, sesame, peanut, cashew, barley, wheat, soybean and pecan. The absolute limit of detection (LODa) of this system is between 2 and 20 copies of haploid genome, and the relative LOD (LODr) is as low as 0.005% (w/w) in simulated food mixtures. The developed assay was subsequently applied to 20 commercial food products and verified the allergen ingredients stated on the labels. Furthermore, results using this decaplex PCR assay was successfully replicated in three other laboratories, demonstrating the repeatability and applicability of this assay in routine analysis of the 10 food allergens.

  1. IL-4 function can be transferred to the IL-2 receptor by tyrosine containing sequences found in the IL-4 receptor alpha chain.

    Science.gov (United States)

    Wang, H Y; Paul, W E; Keegan, A D

    1996-02-01

    IL-4 binds to a cell surface receptor complex that consists of the IL-4 binding protein (IL-4R alpha) and the gamma chain of the IL-2 receptor complex (gamma c). The receptors for IL-4 and IL-2 have several features in common; both use the gamma c as a receptor component, and both activate the Janus kinases JAK-1 and JAK-3. In spite of these similarities, IL-4 evokes specific responses, including the tyrosine phosphorylation of 4PS/IRS-2 and the induction of CD23. To determine whether sequences within the cytoplasmic domain of the IL-4R alpha specify these IL-4-specific responses, we transplanted the insulin IL-4 receptor motif (I4R motif) of the huIL-4R alpha to the cytoplasmic domain of a truncated IL-2R beta. In addition, we transplanted a region that contains peptide sequences shown to block Stat6 binding to DNA. We analyzed the ability of cells expressing these IL-2R-IL-4R chimeric constructs to respond to IL-2. We found that IL-4 function could be transplanted to the IL-2 receptor by these regions and that proliferative and differentiative functions can be induced by different receptor sequences.

  2. Long-term impact of sewage irrigation on soil properties and assessing risk in relation to transfer of metals to human food chain.

    Science.gov (United States)

    Meena, Ramu; Datta, S P; Golui, Debasis; Dwivedi, B S; Meena, M C

    2016-07-01

    A case study was undertaken to assess the risk of sewage-irrigated soils in relation to the transfer of trace elements to rice and wheat grain. For this purpose, peri-urban agricultural lands under the Keshopur Effluent Irrigation Scheme (KEIS) of Delhi were selected. These agricultural lands have been receiving irrigation through sewage effluents since 1979. Sewage effluent, groundwater, soil, and plant (rice and wheat grain) samples were collected with GPS coordinates from this peri-urban area. Under wheat crop, sewage irrigation for four decades resulted into a significant buildup of zinc (141 %), copper (219 %), iron (514 %), nickel (75.0 %), and lead (28.1 %) in sewage-irrigated soils over adjacent tube well water-irrigated ones. Under rice crop, there was also a significant buildup of phosphorus (339 %), sulfur (130 %), zinc (287 %), copper (352 %), iron (457 %), nickel (258 %), lead (136 %), and cadmium (147 %) in sewage-irrigated soils as compared to that of tube well water-irrigated soils. The values of hazard quotient (HQ) for intake of trace toxic elements by humans through consumption of rice and wheat grain grown on these sewage-irrigated soils were well within the safe permissible limit. The variation in Zn, Ni, and Cd content in wheat grain could be explained by solubility-free ion activity model (FIAM) to the extent of 50.1, 56.8, and 37.2 %, respectively. Corresponding values for rice grain were 49.9, 41.2, and 42.7 %, respectively. As high as 36.4 % variation in As content in rice grain could be explained by solubility-FIAM model. Toxic limit of extractable Cd and As in soil for rice in relation to soil properties and human health hazard associated with consumption of rice grain by humans was established. A similar exercise was also done in respect of Cd for wheat. The conceptual framework of fixing the toxic limit of extractable metals and metalloid in soils with respect to soil properties and human health hazard under the

  3. Dietary avocado oil supplementation attenuates the alterations induced by type I diabetes and oxidative stress in electron transfer at the complex II-complex III segment of the electron transport chain in rat kidney mitochondria.

    Science.gov (United States)

    Ortiz-Avila, Omar; Sámano-García, Carlos Alberto; Calderón-Cortés, Elizabeth; Pérez-Hernández, Ismael H; Mejía-Zepeda, Ricardo; Rodríguez-Orozco, Alain R; Saavedra-Molina, Alfredo; Cortés-Rojo, Christian

    2013-06-01

    Impaired complex III activity and reactive oxygen species (ROS) generation in mitochondria have been identified as key events leading to renal damage during diabetes. Due to its high content of oleic acid and antioxidants, we aimed to test whether avocado oil may attenuate the alterations in electron transfer at complex III induced by diabetes by a mechanism related with increased resistance to lipid peroxidation. 90 days of avocado oil administration prevented the impairment in succinate-cytochrome c oxidoreductase activity caused by streptozotocin-induced diabetes in kidney mitochondria. This was associated with a protection against decreased electron transfer through high potential chain in complex III related to cytochromes c + c1 loss. During Fe(2+)-induced oxidative stress, avocado oil improved the activities of complexes II and III and enhanced the protection conferred by a lipophilic antioxidant against damage by Fe(2+). Avocado oil also decreased ROS generation in Fe(2+)-damaged mitochondria. Alterations in the ratio of C20:4/C18:2 fatty acids were observed in mitochondria from diabetic animals that not were corrected by avocado oil treatment, which yielded lower peroxidizability indexes only in diabetic mitochondria although avocado oil caused an augment in the total content of monounsaturated fatty acids. Moreover, a protective effect of avocado oil against lipid peroxidation was observed consistently only in control mitochondria. Since the beneficial effects of avocado oil in diabetic mitochondria were not related to increased resistance to lipid peroxidation, these effects were discussed in terms of the antioxidant activity of both C18:1 and the carotenoids reported to be contained in avocado oil.

  4. Effect of chain length on aggregation of n-alkanes in CCl3F matrices at 77 K. Further ESR evidence for the occurrence of hydrogen and/or proton transfer between higher alkanes and their cations

    International Nuclear Information System (INIS)

    After γ-irradiation of hexane and decane at low concentration in CCl3F at 77 K only the ESR spectrum of the corresponding radical cations is observed. At higher concentrations (from about 3 mol% hexane and 0.5 mol% decane), the spectra of alkyl radicals also appear. The signal intensity and relative contribution of these alkyl radicals to the observed ESR spectra increases with increasing alkane solute concentration. In contrast, alkane radical cations but no alkyl radicals are observed after irradiation of hexane and decane in CCl3CF3 and other matrices at concentrations where alkyl radicals are already quite prominent in CCl3F. This contrast is especially pronounced in the case of decane, the signal intensity and relative contribution of alkyl radicals in the ESR spectrum of irradiated CCl3F-decane systems being much higher than in irradiated CCl3F-hexane systems. Most of the alkane radical cations observed possess the extended structure, resulting in a triplet with substructure for hexane and a broad singlet for decane, but different conformers are also observed, viz. for hexane in CCl3CF3 and for decane in CCl3F. The results provide conclusive evidence for the occurrence of hydrogen and/or proton transfer between C6 (only weakly) and C10 (very pronounced) n-alkanes and their cations. They show further that in CCl3F at 77 K alkanes are present as small aggregates to which hole transfer still occurs efficiently and, in conjunction with other data, indicate that the extent of such aggregation increases with increasing chain length of the alkane solute. (Author)

  5. Chain Gang

    Science.gov (United States)

    2006-01-01

    6 August 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a chain of clustered and battered craters. These were formed by secondary impact. That is, somewhere to the south (beyond the bottom of this image), a large impact crater formed. When this occurred, material ejected from the crater was thrown tens to hundreds of kilometers away. This material then impacted the martian surface, forming clusters and chains of smaller craters. Location near: 15.8oN, 35.6oW Image width: 3 km (1.9 mi) Illumination from: upper left Season: Northern Spring

  6. Application of a real-time fluorescence resonance energy transfer polymerase chain reaction assay with melting curve analysis for the detection of Paragonimus heterotremus eggs in the feces of experimentally infected cats.

    Science.gov (United States)

    Tantrawatpan, Chairat; Intapan, Pewpan M; Thanchomnang, Tongjit; Sanpool, Oranuch; Janwan, Penchom; Lulitanond, Viraphong; Anamnart, Witthaya; Maleewong, Wanchai

    2013-09-01

    Paragonimus heterotremus is a medically important lung fluke that causes human and animal paragonimiasis in Southeast Asia, including Thailand. In the current study, a real-time fluorescence resonance energy transfer polymerase chain reaction (real-time FRET PCR) with melting curve analysis was developed and evaluated to detect P. heterotremus eggs in the feces of experimentally infected cats. The detection limit of this method for the P. heterotremus DNA sequence was 3 × 10(2) copies of the positive control plasmid and 10(-3) ng of P. heterotremus genomic DNA. The assay system could detect 10 eggs of P. heterotremus per gram of cat feces. No fluorescence signal was observed when DNA purified from 16 other organisms or genomic DNA from cats and human beings were tested. Real-time FRET PCR yielded positive results for all fecal samples from 17 P. heterotremus-infected cats and showed a negative relationship (r = -0.852, P Paragonimus species examined were divided into 4 groups by melting peak analysis. This assay can be useful for the detection of, and epidemiological studies on, P. heterotremus infection in endemic areas.

  7. Chain Teleportation

    OpenAIRE

    Lee, Chien-er

    2004-01-01

    By means of the idea of measurements on the crossed space-time nonlocal observables, we extend the mechanism for the two-way quantum teleportation to the chain teleportation among N spatially separated spin-1/2 systems. Since in the process only the local interactions are used, the microcausality is automatically satisfied.

  8. Extended linear chain compounds

    CERN Document Server

    Linear chain substances span a large cross section of contemporary chemistry ranging from covalent polymers, to organic charge transfer com­ plexes to nonstoichiometric transition metal coordination complexes. Their commonality, which coalesced intense interest in the theoretical and exper­ imental solid state physics/chemistry communities, was based on the obser­ vation that these inorganic and organic polymeric substrates exhibit striking metal-like electrical and optical properties. Exploitation and extension of these systems has led to the systematic study of both the chemistry and physics of highly and poorly conducting linear chain substances. To gain a salient understanding of these complex materials rich in anomalous aniso­ tropic electrical, optical, magnetic, and mechanical properties, the conver­ gence of diverse skills and talents was required. The constructive blending of traditionally segregated disciplines such as synthetic and physical organic, inorganic, and polymer chemistry, crystallog...

  9. Catch Chain

    OpenAIRE

    Talbert, Robert

    2010-01-01

    Catch Chain is a book of poems that traces the journey of a Corrections Officer who attempts to combat issues of isolation, inhumane treatment of inmates and societal rejection in jails by embarking upon a cross-country road trip. However, the same issues the officer initially wrestled with begin cropping up in different cities, on various highways and in a multitude of states. The excitement and adventure of the open road runs parallel to the recurring imprisonment of the guard's mind.

  10. Large Deviations in Quantum Spin Chain

    CERN Document Server

    Ogata, Yoshiko

    2008-01-01

    We show the full large deviation principle for KMS-states and $C^*$-finitely correlated states on a quantum spin chain. We cover general local observables. Our main tool is Ruelle's transfer operator method.

  11. On Diagnostic Index and Method of Healthy Wetland Food Chain

    OpenAIRE

    Li-Juan Cui; Xin-sheng Zhao; Wei Li

    2013-01-01

    Wetland food chain is the channel of the matter and energy transfer or flow in the wetland ecosystem. From wetland food chain scission mechanism, the structure and functional characteristics of the wetland food chain scission were analyzed, while building a healthy wetland food chain diagnostic index system. Depending on wetland ecosystem health research results, this study brought forward the wetland food chain structure stability and functions of wetland energy measures and their quantitati...

  12. 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

  13. Electron transfer in peptides.

    Science.gov (United States)

    Shah, Afzal; Adhikari, Bimalendu; Martic, Sanela; Munir, Azeema; Shahzad, Suniya; Ahmad, Khurshid; Kraatz, Heinz-Bernhard

    2015-02-21

    In this review, we discuss the factors that influence electron transfer in peptides. We summarize experimental results from solution and surface studies and highlight the ongoing debate on the mechanistic aspects of this fundamental reaction. Here, we provide a balanced approach that remains unbiased and does not favor one mechanistic view over another. Support for a putative hopping mechanism in which an electron transfers in a stepwise manner is contrasted with experimental results that support electron tunneling or even some form of ballistic transfer or a pathway transfer for an electron between donor and acceptor sites. In some cases, experimental evidence suggests that a change in the electron transfer mechanism occurs as a result of donor-acceptor separation. However, this common understanding of the switch between tunneling and hopping as a function of chain length is not sufficient for explaining electron transfer in peptides. Apart from chain length, several other factors such as the extent of the secondary structure, backbone conformation, dipole orientation, the presence of special amino acids, hydrogen bonding, and the dynamic properties of a peptide also influence the rate and mode of electron transfer in peptides. Electron transfer plays a key role in physical, chemical and biological systems, so its control is a fundamental task in bioelectrochemical systems, the design of peptide based sensors and molecular junctions. Therefore, this topic is at the heart of a number of biological and technological processes and thus remains of vital interest.

  14. Chain reaction

    International Nuclear Information System (INIS)

    Chain Reaction is a work of recent American political history. It seeks to explain how and why America came to depend so heavily on its experts after World War II, how those experts translated that authority into political clout, and why that authority and political discretion declined in the 1970s. The author's research into the internal memoranda of the Atomic Energy Commission substantiates his argument in historical detail. It was not the ravages of American anti-intellectualism, as so many scholars have argued, that brought the experts back down to earth. Rather, their decline can be traced to the very roots of their success after World War II. The need to over-state anticipated results in order to garner public support, incessant professional and bureaucratic specialization, and the sheer proliferation of expertise pushed arcane and insulated debates between experts into public forums at the same time that a broad cross section of political participants found it easier to gain access to their own expertise. These tendencies ultimately undermined the political influence of all experts. (author)

  15. Chain length dependence of non-surface activity and micellization behavior of cationic amphiphilic diblock copolymers.

    Science.gov (United States)

    Ghosh, Arjun; Yusa, Shin-ichi; Matsuoka, Hideki; Saruwatari, Yoshiyuki

    2014-04-01

    The cationic and anionic amphiphilic diblock copolymers with a critical chain length and block ratio do not adsorb at the air/water interface but form micelles in solution, which is a phenomenon called "non-surface activity". This is primarily due to the high charge density of the block copolymer, which creates a strong image charge effect at the air/water interface preventing adsorption. Very stable micelle formation in bulk solution could also play an important role in the non-surface activity. To further confirm these unique properties, we studied the adsorption and micellization behavior of cationic amphiphilic diblock copolymers of poly(n-butyl acrylate)-b-poly(3-(methacryloyloxy)ethyl)trimethylammonium chloride) (PBA-b-PDMC) with different molecular weights of hydrophobic blocks but with the same ionic block length. These block copolymers were successfully prepared via consecutive reversible addition-fragmentation chain transfer (RAFT) polymerization. The block copolymer with the shortest hydrophobic block length was surface-active; the solution showed surface tension reduction and foam formation. However, above the critical block ratio, the surface tension of the solution did not decrease with increasing polymer concentration, and there was no foam formation, indicating lack of surface activity. After addition of 0.1 M NaCl, stable foam formation and slight reduction of surface tension were observed, which is reminiscent of the electrostatic nature of the non-surface activity. Fluorescence and dynamic and static light scattering measurements showed that the copolymer with the shortest hydrophobic block did not form micelles, while the block copolymers formed spherical micelles having radii of 25-30 nm. These observations indicate that micelle formation is also important for non-surface activity. Upon addition of NaCl, cmc did not decrease but rather increased as observed for non-surface-active block copolymers previously studied. The micelles formed were

  16. Newton's cradle and entanglement transport in a flexible Rydberg chain

    CERN Document Server

    Wüster, S; Eisfeld, A; Rost, J -M

    2010-01-01

    In a regular, flexible chain of Rydberg atoms, a single electronic excitation localizes on two atoms that are in closer mutual proximity than all others. We show how the interplay between excitonic and atomic motion causes electronic excitation and diatomic proximity to propagate through the Rydberg chain as a combined pulse. In this manner entanglement is transferred adiabatically along the chain, reminiscent of momentum transfer in Newton's cradle.

  17. The chemical behaviour and ecological transfer in human food chain of some radionuclides in aqueous ecosystems and their risk on population health. Part of a coordinated programme on radiological and environmental protection studies in the Danube River catchment area

    International Nuclear Information System (INIS)

    The radioecological concentration of H-3, K-40, Sr-90, Cs-137, and Ra-226 in the Danube River catchment area in Romania as well as the migration of these radionuclides in the food chain was determined. It was found that the concentration of each of these radionuclides in the Danube water was very low and that the radioactivity in the food chain was lower than the maximum permissible level. Very low incidence of cancer was detected among the inhabitants along the river

  18. Chain reconfiguration in active noise

    International Nuclear Information System (INIS)

    In a typical single molecule experiment, the dynamics of an unfolded protein is studied by determining the reconfiguration time using long-range Förster resonance energy transfer, where the reconfiguration time is the characteristic decay time of the position correlation between two residues of the protein. In this paper we theoretically calculate the reconfiguration time for a single flexible polymer in the presence of active noise. The study suggests that though the mean square displacement grows faster, the chain reconfiguration is always slower in the presence of long-lived active noise with exponential temporal correlation. Similar behavior is observed for a worm-like semi-flexible chain and a Zimm chain. However it is primarily the characteristic correlation time of the active noise and not the strength that controls the increase in the reconfiguration time. In brief, such active noise makes the polymer move faster but the correlation loss between the monomers becomes slow. (paper)

  19. Precise Nanoelectronics with Adatom Chains

    Science.gov (United States)

    Yamada, Toshishige

    1999-01-01

    Adatom chains on an atomically regulated substrate will be building components in future precise nanoelectronics. Adatoms need to be secured with chemical bonding, but then electronic isolation between the adatom and substrate systems is not guaranteed. A one-dimensional model shows that good isolation with existence of surface states is expected on an s-p crossing substrate such as Si, Ge, or GaAs, reflecting the bulk nature of the substrate. Isolation is better if adatoms are electronically similar to the substrate atoms, and can be manipulated by hydrogenation. Chain structures with group IV adatoms with two chemical bonds, or group III adatoms with one chemical bond, are semiconducting, reflecting the surface nature of the substrate. These structures are unintentionally doped due to the charge transfer across the chemical bonds. Physical properties of adatom chains have to be determined for the unified adatom-substrate system.

  20. Practicality of spin chain 'wiring' in diamond quantum technologies

    OpenAIRE

    Ping, Yuting; Lovett, Brendon William; Benjamin, Simon C.; Gauger, Erik M.

    2012-01-01

    Coupled spin chains are promising candidates for wiring up qubits in solid-state quantum computing (QC). In particular, two nitrogen-vacancy centers in diamond can be connected by a chain of implanted nitrogen impurities; when driven by suitable global fields the chain can potentially enable quantum state transfer at room temperature. However, our detailed analysis of error effects suggests that foreseeable systems may fall far short of the fidelities required for QC. Fortunately the chain ca...

  1. 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

  2. Silicone chain extender

    DEFF Research Database (Denmark)

    2015-01-01

    The present invention relates to a silicone chain extender, more particularly a chain extender for silicone polymers and copolymers, to a chain extended silicone polymer or copolymer and to a functionalized chain extended silicone polymer or copolymer, to a method for the preparation thereof and...

  3. Health supply chain management.

    Science.gov (United States)

    Zimmerman, Rolf; Gallagher, Pat

    2010-01-01

    This chapter gives an educational overview of: * The actual application of supply chain practice and disciplines required for service delivery improvement within the current health environment. * A rationale for the application of Supply Chain Management (SCM) approaches to the Health sector. * The tools and methods available for supply chain analysis and benchmarking. * Key supply chain success factors. PMID:20407173

  4. Analysis of transfer of 131I and 137Cs deposited after the Chernobyl accident via the grass-cow-milk pathway and comparison with parameters in use with food chain models

    International Nuclear Information System (INIS)

    A variety of measurements of activity concentrations of 131I and 137Cs in cows feed and milk after the Chernobyl accident are compiled and evaluated using the concepts of linear compartmental theory. Minimal compartmental models derived from the various data sets showed no unique structure. Differences, however, could be attributed to limited observation times of experimental data. Calculated weathering half-lives of both isotopes and equilibrium transfer coefficients of cesium are well within the range of data collected from laboratory experiments using fodder contaminated superficially, whereas calculated transfer coefficients of iodine are in the lower range of data reported from laboratory experiments. (19 refs., 1 fig., 3 tabs.)

  5. Backward Charge Transfer in Conjugated Polymers

    Institute of Scientific and Technical Information of China (English)

    CHENG Meng-Xing; LI Guang-Qi; Thomas F. George; SUN Xin

    2005-01-01

    It has been known that the static polarizability of a polymer chain with a biexciton is negative. In order to understand this peculiar fact, this paper studies the dynamical process of the charge transfer in the polymer chain induced by an external electric field E during forming the biexciton. The time dependence of the charge distribution in the chain reveals that the charge transfer is backward: the positive charge shifts in the opposite direction of the external electric field. Such a backward charge transfer (BCT) produces an opposite dipole, which makes the polarization negative. The effect of electron interaction on the BCT is illustrated.

  6. Drying of willow biomass in supply chains

    NARCIS (Netherlands)

    Gigler, J.K.

    2000-01-01

    The drying process of willow ( Salix viminalis ) in biomass supply chains to energy plants is quantitatively described. Drying at particle level was modelled for chips and stems by a diffusion equation linked to the mass transfer of moisture to the air. Drying at bulk level is described by a deep be

  7. Chains of coupled square dielectric optical microcavities

    NARCIS (Netherlands)

    Hammer, Manfred

    2009-01-01

    Chains of coupled square dielectric cavities are investigated in a 2-D setting, by means of a quasi-analytical eigenmode expansion method. Resonant transfer of optical power can be achieved along quite arbitrary, moderately long rectangular paths (up to 9 coupled cavities are considered), even with

  8. New acceptor-bridge-donor strategy for enhancing NLO response with long-range excess electron transfer from the NH2...M/M3O donor (M = Li, Na, K) to inside the electron hole cage C20F19 acceptor through the unusual σ chain bridge (CH2)4.

    Science.gov (United States)

    Bai, Yang; Zhou, Zhong-Jun; Wang, Jia-Jun; Li, Ying; Wu, Di; Chen, Wei; Li, Zhi-Ru; Sun, Chia-Chung

    2013-04-01

    Using the strong electron hole cage C20F19 acceptor, the NH2...M/M3O (M = Li, Na, and K) complicated donors with excess electron, and the unusual σ chain (CH2)4 bridge, we construct a new kind of electride molecular salt e(-)@C20F19-(CH2)4-NH2...M(+)/M3O(+) (M = Li, Na, and K) with excess electron anion inside the hole cage (to be encapsulated excess electron-hole pair) serving as a new A-B-D strategy for enhancing nonlinear optical (NLO) response. An interesting push-pull mechanism of excess electron generation and its long-range transfer is exhibited. The excess electron is pushed out from the (super)alkali atom M/M3O by the lone pair of NH2 in the donor and further pulled inside the hole cage C20F19 acceptor through the efficient long σ chain (CH2)4 bridge. Owing to the long-range electron transfer, the new designed electride molecular salts with the excess electron-hole pair exhibit large NLO response. For the e(-)@C20F19-(CH2)4-NH2...Na(+), its large first hyperpolarizability (β0) reaches up to 9.5 × 10(6) au, which is about 2.4 × 10(4) times the 400 au for the relative e(-)@C20F20...Na(+) without the extended chain (CH2)4-NH2. It is shown that the new strategy is considerably efficient in enhancing the NLO response for the salts. In addition, the effects of different bridges and alkali atomic number on β0 are also exhibited. Further, three modulating factors are found for enhancing NLO response. They are the σ chain bridge, bridge-end group with lone pair, and (super)alkali atom. The new knowledge may be significant for designing new NLO materials and electronic devices with electrons inside the cages. They may also be the basis of establishing potential organic chemistry with electron-hole pair.

  9. 我国农村土地间接流转供应链的利益协调机制研究--基于委托代理模型%Research on the Benefits’ Coordination Mechanism in the Supply Chain of Indirect Rural Land Transferring---Based on the Principal-agent Model

    Institute of Scientific and Technical Information of China (English)

    何芳; 温修春

    2013-01-01

    利益冲突是供应链中的一个共性问题,因而建立合理的利益协调机制对农村土地流转的成功运作无疑是重要的。本文应用博弈论建立了供应链中利益协调的博弈模型---一个两阶段的委托代理模型,以此来分析我国农村土地间接流转模式运作中存在的双重委托代理风险问题,以至于可采取各种措施和手段促进供应链中的信息沟通与协调行为。最后,通过数值模拟与数值算例说明了机制设计的有效性,并对分析结果进行验证。研究结果表明,通过选择合理的机制可以使供应链各成员的期望收益达到帕累托改进,从而实现农村土地间接流转供应链系统的协调。%Because the conflicts of benefits are the common problems in the supply chain ,so establishing a ration-al benefits’ coordination mechanisms is undoubtedly important to the successful operation of rural land transfer -ring.In this paper , based on the game theory , a model of the benefits ’ coordination mechanism , i.e a two-stage’s principal-agent model, is set up to analyze the moral risk problems of the double principal-agent, so as to promote communication and coordination behavior by a variety of means and measures .Finally, the validity of the combined mechanism is illustrated by a numerical simulation and a numerical example .It is revealed that via selecting the rational mechanism , each member in the indirect land transferring supply chain can make a Pareto improvement in the expected benefits , and coordination of the indirect land transferring supply chain can be achieved in the end .

  10. Chain-Chain Based Routing Protocol

    Directory of Open Access Journals (Sweden)

    Samia A Ali

    2011-05-01

    Full Text Available Wireless sensor network (WSN is an emerging technology for monitoring physical world. WSNs consist of large numbers of sensor nodes operated by battery mostly in harsh environment. Thus energy conservation is a primary issue for organization of these sensor nodes. Another crucial issue is the data delivery time by sensor nodes to the sink node, especially in Military, medical fields, and security monitoring systems where minimum delay is desirable. Number of protocols has been proposed in the literature for routing. One of such protocols is the cluster based routing protocol LEACH (low energy adaptive clustering hierarchy. LEACH protocol organizes WSN into a set of clusters and a periodic voting for cluster head is performed in order to be evenly distributed among all the sensors of the WSN. This periodical cluster head voting in LEACH, however, consumes an amount of non-negligible energy and other resources. For energy conservation, PEGASIS (power efficient gathering in sensor information systems a near optimal chain-based protocol has been proposed, however, it is faced with the challenge of long delay for the transmitted data. Another routing protocol called CCM (Chain-Cluster based Mixed routing, which is mainly a hybrid of LEACH and PEGASIS is proposed, the consumed energy increases as network size increases. In this paper, we propose an efficient routing protocol called CCBRP (Chain-Chain based routing protocol, it achieves both minimum energy consumption and minimum delay. The CCBRP protocol mainly divides a WSN into a number of chains (Greedy algorithm is used to form each chain as in PEGSIS protocol and runs in two phases. In the first phase, sensor nodes in each chain transmit data to their chain leader nodes in parallel. In the second phase, all chain leader nodes form a chain (also, using Greedy algorithm and choose randomly a leader node then all chain leader nodes send their data to this chosen leader node. This chosen leader node

  11. Free radical transfer in polymers

    International Nuclear Information System (INIS)

    For the present study of free-radical transfer in polymers pulse radiolysis and product studies have been carried out in aqueous solutions using thus far only the water-soluble polymers polyacrylic acid, polymethacrylic acid and polyvinyl alcohol. When OH radicals, generated in the radiolysis of N2O-saturated aqueous solutions, react with polymers the lifetime of the polymer radical thus created very much depends on the number of radicals per polymer chain. When there are a large number of radicals per chain their bimolecular decay may be faster than the corresponding (diffusion controlled) decay of monomeric radicals, but when the macromolecule contains only few or even just one radical their lifetime is considerably prolonged. Highly charged polymers such as polyacrylic acid at high pH attain a rod-like conformation which again favors a long lifetime of the radicals. Under such conditions, radical transfer reactions can occur. For example, in polyacrylic acid OH radicals generate two kinds of radicals side by side. The radical in β-position to the carboxylate group converts into the thermodynamically more stable α-radicals by an H-transfer reaction as can be followed by spectrophotometry. Besides radical transfer reactions β-fragmentation reactions occur causing chain scission. Such reactions can be followed in a pulse radiolysis experiment by conductometry, because counter ions are released upon chain scission. Such a process is especially effective in the case of polymethacrylic acid, where it results in a chain depolymerization. An intramolecular H-abstraction is also observed in the γ-radiolysis of polyacrylic acid with the corresponding peroxyl radicals. This causes a chain reaction to occur. The resulting hydroperoxides are unstable and decarboxylate given rise to acetylacetone-like products. In polyvinyl alcohol the peroxyl radicals in α-position to the alcohol function undergo HO2-elimination. This prevents a scission of the polymer chain in the

  12. Accumulation and transfer of Hg, As, Se, and other metals in the sediment-vegetation-crab-human food chain in the coastal zone of the northern Brazilian state of Pará (Amazonia).

    Science.gov (United States)

    Vilhena, Maria S P; Costa, Marcondes L; Berredo, Jose Francisco

    2013-08-01

    The high consumption of crabs (Ucides cordatus) stimulated interest in the present study on the northern coast of Brazil, which encompasses a preserved area of mangrove forest. The objective was to describe and quantify the transfer of metals from the muddy sediments to the leaves of the Rhizophora mangle, and thence the crabs and humans. The samples were collected along two transects, while samples of hair were obtained from local habitants. The pH, interstitial salinity, Eh (mV) were measured, the granulometry and mineralogical and multi-element chemical analyses were run, and the organic material determined. The sediments are silty-clayey, composed of quartz, kaolinite, iron oxides, and illite, as well as smaller portions of smectite, pyrite, halite, and high levels of SiO2 (56.5 %), Al2O3 (18.5 %), and Fe2O3 (7 %). The elements Zn, Sr, As, and Zr are concentrated in the leaves, while the bioaccumulation of Zn, Se, Sr, and As was recorded in the crabs, of which, Se is the most concentrated in the tissue of the muscles and the hepatopancreas. The concentrations of nutrient and toxic elements were similar in all age groups (hair samples), with only Hg presenting an increasing concentration between infants and adults. The highest rates of transfer were recorded for the elements Zn and Se in the crabs and Hg in leaves and hair. The accumulation of metals in the leaves and crabs reflects the chemical composition of the sediments and low rates of sediment-vegetation-crab transfer, with the exception of Hg, which accumulated in the hair. PMID:23334486

  13. Discrete Quantum Markov Chains

    CERN Document Server

    Faigle, Ulrich

    2010-01-01

    A framework for finite-dimensional quantum Markov chains on Hilbert spaces is introduced. Quantum Markov chains generalize both classical Markov chains with possibly hidden states and existing models of quantum walks on finite graphs. Quantum Markov chains are based on Markov operations that may be applied to quantum systems and include quantum measurements, for example. It is proved that quantum Markov chains are asymptotically stationary and hence possess ergodic and entropic properties. With a quantum Markov chain one may associate a quantum Markov process, which is a stochastic process in the classical sense. Generalized Markov chains allow a representation with respect to a generalized Markov source model with definite (but possibly hidden) states relative to which observables give rise to classical stochastic processes. It is demonstrated that this model allows for observables to violate Bell's inequality.

  14. Transfer Pricing

    DEFF Research Database (Denmark)

    Nielsen, Søren Bo

    2014-01-01

    Against a background of rather mixed evidence about transfer pricing practices in multinational enterprises (MNEs) and varying attitudes on the part of tax authorities, this paper explores how multiple aims in transfer pricing can be pursued across four different transfer pricing regimes. A MNE h...

  15. Respiratory electron transfer in Escherichia coli : components, energetics and regulation

    NARCIS (Netherlands)

    M. Bekker

    2009-01-01

    The respiratory chain that is housed in the bacterial cytoplasmic membrane, generally transfers electrons from NADH to oxygen; in the absence of oxygen it can use several alternative electron acceptors, such as nitrate and fumarate. Transfer of electrons through this chain is usually coupled to the

  16. Supply Chain Management og Supply Chain costing

    DEFF Research Database (Denmark)

    Nielsen, Steen; Mortensen, Ole

    2002-01-01

    Formålet med denne artikel er at belyse de muligheder som ligger i at integrere virksomhedens økonomiske styring med begrebet Supply Chain Management (SCM). Dette søges belyst ved først at beskrive den teoretiske ramme, hvori SCM indgår. Herefter analyseres begrebet Supply Chain Costing (SCC) som...... Århus. Et resultat er, at via begrebet Supply Chain Costing skabes der mulighed for at måle logistikkædens aktiviteter i kr./øre. Anvendelsen af denne information har også strategisk betydning for at kunne vælge kunde og leverandør. Ved hjælp af integrationen skabes der også helt nye mulighed...

  17. Understanding the Chain Fountain

    CERN Document Server

    Biggins, John Simeon

    2013-01-01

    If a chain is initially at rest in a beaker at a height h1 above the ground, and the end of the chain is pulled over the rim of the beaker and down towards the ground and then released, the chain will spontaneously "flow" out of the beaker under gravity. Furthermore, if h1 is sufficient, the beads do not simply drag over the edge of the beaker but form a fountain reaching a height h2 above it. We show that the formation of a fountain requires that the beads come into motion not only by being pulled upwards by the part of the chain immediately above the pile, but also by being pushed upwards by an anomalous reaction force from the pile of stationary chain. We propose possible origins for this force, argue that its magnitude will be proportional to the square of the chain velocity, and predict and verify experimentally that h2 is proportional to h1.

  18. Food supply chains

    OpenAIRE

    Zhou, Qian

    2011-01-01

    The dissertation analyses food waste in global supply chain. From the related managerial literature, the process of supply chain operation, from agriculture, manufacturing, warehouses, retailers to customers are explained clearly. Then the reasons and characteristics of food wastes in any point of food supply chain are analyzed. From some case studies and questionnaire investigation, some corresponding methods to reduce food waste are put forward in the following. Lastly, in terms of method s...

  19. Economy, market and chain

    OpenAIRE

    Sukkel, W.; Hommes, M.

    2009-01-01

    In their pursuit of growth and professionalisation, the Dutch organic sector focuses primarily on market development. But how do you stimulate the market for organic foods? This is the subject of many research projects concerning market, consumer preferences and the supply chain. These projects focus specifically at consumer purchasing behaviour, product development, supply chain formation and minimising cost price. As a rule, this research takes place in close cooperation with chain actors

  20. Supply Chain Collaboration

    OpenAIRE

    Meca, Ana; Timmer, Judith

    2008-01-01

    In this chaper, we have reviewed and surveyed the literature on supply chain collaboration. As mentioned above, the game theory models that include cooperative behaviour among retailers seem to be a natural framework to model cooperation (collaboration) in supply chains that consist of a supplier and a finite number of retailers. Various researchers in this area have already adopted several cooperative models dealing with supply chain coordination, and it is expected to see many more in the n...

  1. Sustainable Supply Chain Management

    OpenAIRE

    Geentjens, Marlies

    2013-01-01

    This project investigates the phenomena Sustainable Supply Chain Management. The point of departure is Supply Chain Management, which we analyse in order to lock into an understanding of the development that occur when implementing sustainability. In the quest for higher understanding of the interlocking mechanisms of supply chain management, we combine a theoretical approach to the developmnent of sustainability with some relevant case-examples (mainly depicting IKEA). This focal point g...

  2. Supply chain components

    Directory of Open Access Journals (Sweden)

    Vieraşu, T.

    2011-01-01

    Full Text Available In this article I will go through three main logistics components, which are represented by: transportation, inventory and facilities, and the three secondary logistical components: information, production location, price and how they determine performance of any supply chain. I will discuss then how these components are used in the design, planning and operation of a supply chain. I will also talk about some obstacles a supply chain manager may encounter.

  3. Supply chain components

    OpenAIRE

    Vieraşu, T.; Bălăşescu, M.

    2011-01-01

    In this article I will go through three main logistics components, which are represented by: transportation, inventory and facilities, and the three secondary logistical components: information, production location, price and how they determine performance of any supply chain. I will discuss then how these components are used in the design, planning and operation of a supply chain. I will also talk about some obstacles a supply chain manager may encounter.

  4. Ecosystem-based approach for the numerical modelling of {sup 137}Cs transfer to the western North Pacific plankton populations after the Fukushima nuclear power plant accident - New approach for the modelling of radiocesium in pelagic food chain in the Northwestern Pacific after the Fukushima nuclear power plant accident

    Energy Technology Data Exchange (ETDEWEB)

    Belharet, Mokrane [Institut de Radioprotection et de Surete Nucleaire, SESURE/ LERCM, 83507 La Seyne-sur-mer (France); Laboratoire d' Aerologie, 14 av Eduard Belin, 31400 Toulouse (France); Estournel, Claude [Laboratoire d' Aerologie, 14 av Eduard Belin, 31400 Toulouse (France); Charmasson, Sabine [Institut de Radioprotection et de Surete Nucleaire, SESURE/ LERCM, 83507 La Seyne-sur-mer (France)

    2014-07-01

    Huge quantities of radiocesium ({sup 134}Cs and {sup 137}Cs) were released to the coastal northwestern Pacific ocean after the Fukushima nuclear power plant accident, that occurred on 11 March 2011. The resultant radiocesium contamination was quickly transferred to marine biota resulting in elevated cesium levels measured in various organisms sampled over this area. This study aims to understand the mechanism of radiocesium behavior in the marine food chain under this non steady state situation (accident) and to estimate contamination levels in these organisms, by using a new modelling approach based on the coupling of three different models: a model of cesium dispersion in the ocean, an ecosystem model and a radioecological model. The model was run for 2 years (2011 and 2012) and was first applied to study marine plankton and planktonivorous fishes contamination. Results of spatio-temporal radiocesium activities in these different organisms, and calculated parameters like concentration ratios, biological half-lives, percentages of contamination coming from each compartment (food and water), and trophic transfer factors were compared to the observed values acquired before and after the accident (steady and non-steady states). (authors)

  5. The NDUFB6 subunit of the mitochondrial respiratory chain complex I is required for electron transfer activity: A proof of principle study on stable and controlled RNA interference in human cell lines

    International Nuclear Information System (INIS)

    Highlights: → NDUFB6 is required for activity of mitochondrial complex I in human cell lines. → Lentivirus based RNA interference results in frequent off target insertions. → Flp-In recombinase mediated miRNA insertion allows gene-specific extinction. -- Abstract: Molecular bases of inherited deficiencies of mitochondrial respiratory chain complex I are still unknown in a high proportion of patients. Among 45 subunits making up this large complex, more than half has unknown function(s). Understanding the function of these subunits would contribute to our knowledge on mitochondrial physiology but might also reveal that some of these subunits are not required for the catalytic activity of the complex. A direct consequence of this finding would be the reduction of the number of candidate genes to be sequenced in patients with decreased complex I activity. In this study, we tested two different methods to stably extinct complex I subunits in cultured cells. We first found that lentivirus-mediated shRNA expression frequently resulted in the unpredicted extinction of additional gene(s) beside targeted ones. This can be ascribed to uncontrolled genetic material insertions in the genome of the host cell. This approach thus appeared inappropriate to study unknown functions of a gene. Next, we found it possible to specifically extinct a CI subunit gene by direct insertion of a miR targeting CI subunits in a Flp site (HEK293 Flp-In cells). By using this strategy we unambiguously demonstrated that the NDUFB6 subunit is required for complex I activity, and defined conditions suitable to undertake a systematic and stable extinction of the different supernumerary subunits in human cells.

  6. The NDUFB6 subunit of the mitochondrial respiratory chain complex I is required for electron transfer activity: A proof of principle study on stable and controlled RNA interference in human cell lines

    Energy Technology Data Exchange (ETDEWEB)

    Loublier, Sandrine; Bayot, Aurelien; Rak, Malgorzata; El-Khoury, Riyad; Benit, Paule [Inserm U676, Hopital Robert Debre, F-75019 Paris (France); Universite Paris 7, Faculte de medecine Denis Diderot, IFR02 Paris (France); Rustin, Pierre, E-mail: pierre.rustin@inserm.fr [Inserm U676, Hopital Robert Debre, F-75019 Paris (France); Universite Paris 7, Faculte de medecine Denis Diderot, IFR02 Paris (France)

    2011-10-22

    Highlights: {yields} NDUFB6 is required for activity of mitochondrial complex I in human cell lines. {yields} Lentivirus based RNA interference results in frequent off target insertions. {yields} Flp-In recombinase mediated miRNA insertion allows gene-specific extinction. -- Abstract: Molecular bases of inherited deficiencies of mitochondrial respiratory chain complex I are still unknown in a high proportion of patients. Among 45 subunits making up this large complex, more than half has unknown function(s). Understanding the function of these subunits would contribute to our knowledge on mitochondrial physiology but might also reveal that some of these subunits are not required for the catalytic activity of the complex. A direct consequence of this finding would be the reduction of the number of candidate genes to be sequenced in patients with decreased complex I activity. In this study, we tested two different methods to stably extinct complex I subunits in cultured cells. We first found that lentivirus-mediated shRNA expression frequently resulted in the unpredicted extinction of additional gene(s) beside targeted ones. This can be ascribed to uncontrolled genetic material insertions in the genome of the host cell. This approach thus appeared inappropriate to study unknown functions of a gene. Next, we found it possible to specifically extinct a CI subunit gene by direct insertion of a miR targeting CI subunits in a Flp site (HEK293 Flp-In cells). By using this strategy we unambiguously demonstrated that the NDUFB6 subunit is required for complex I activity, and defined conditions suitable to undertake a systematic and stable extinction of the different supernumerary subunits in human cells.

  7. Quantum spin transistor with a Heisenberg spin chain

    Science.gov (United States)

    Marchukov, O. V.; Volosniev, A. G.; Valiente, M.; Petrosyan, D.; Zinner, N. T.

    2016-10-01

    Spin chains are paradigmatic systems for the studies of quantum phases and phase transitions, and for quantum information applications, including quantum computation and short-distance quantum communication. Here we propose and analyse a scheme for conditional state transfer in a Heisenberg XXZ spin chain which realizes a quantum spin transistor. In our scheme, the absence or presence of a control spin excitation in the central gate part of the spin chain results in either perfect transfer of an arbitrary state of a target spin between the weakly coupled input and output ports, or its complete blockade at the input port. We also discuss a possible proof-of-concept realization of the corresponding spin chain with a one-dimensional ensemble of cold atoms with strong contact interactions. Our scheme is generally applicable to various implementations of tunable spin chains, and it paves the way for the realization of integrated quantum logic elements.

  8. Value Chain Engineering

    DEFF Research Database (Denmark)

    Wæhrens, Brian Vejrum; Slepniov, Dmitrij

    2015-01-01

    This workbook is recommended for the attention of students of and managers in Danish small and medium sized enterprises (SMEs). Danish SMEs are currently facing a number of key challenges related to their position in global value chains. This book provides an insight into value chain management t...

  9. Interaction of poxvirus intracellular mature virion proteins with the TPR domain of kinesin light chain in live infected cells revealed by two-photon-induced fluorescence resonance energy transfer fluorescence lifetime imaging microscopy.

    Science.gov (United States)

    Jeshtadi, Ananya; Burgos, Pierre; Stubbs, Christopher D; Parker, Anthony W; King, Linda A; Skinner, Michael A; Botchway, Stanley W

    2010-12-01

    Using two-photon-induced fluorescence lifetime imaging microscopy, we corroborate an interaction (previously demonstrated by yeast two-hybrid domain analysis) of full-length vaccinia virus (VACV; an orthopoxvirus) A36 protein with the cellular microtubule motor protein kinesin. Quenching of enhanced green fluorescent protein (EGFP), fused to the C terminus of VACV A36, by monomeric red fluorescent protein (mDsRed), fused to the tetratricopeptide repeat (TPR) domain of kinesin, was observed in live chicken embryo fibroblasts infected with either modified vaccinia virus Ankara (MVA) or wild-type fowlpox virus (FWPV; an avipoxvirus), and the excited-state fluorescence lifetime of EGFP was reduced from 2.5 ± 0.1 ns to 2.1 ± 0.1 ns due to resonance energy transfer to mDsRed. FWPV does not encode an equivalent of intracellular enveloped virion surface protein A36, yet it is likely that this virus too must interact with kinesin to facilitate intracellular virion transport. To investigate possible interactions between innate FWPV proteins and kinesin, recombinant FWPVs expressing EGFP fused to the N termini of FWPV structural proteins Fpv140, Fpv168, Fpv191, and Fpv198 (equivalent to VACV H3, A4, p4c, and A34, respectively) were generated. EGFP fusions of intracellular mature virion (IMV) surface protein Fpv140 and type II membrane protein Fpv198 were quenched by mDsRed-TPR in recombinant FWPV-infected cells, indicating that these virion proteins are found within 10 nm of mDsRed-TPR. In contrast, and as expected, EGFP fusions of the IMV core protein Fpv168 did not show any quenching. Interestingly, the p4c-like protein Fpv191, which demonstrates late association with preassembled IMV, also did not show any quenching.

  10. Transfer Pricing

    DEFF Research Database (Denmark)

    Rohde, Carsten; Rossing, Christian Plesner

    trade internally as the units have to decide what prices should be paid for such inter-unit transfers. One important challenge is to uncover the consequences that different transfer prices have on the willingness in the organizational units to coordinate activities and trade internally. At the same time...

  11. Integrated supply chain risk management

    OpenAIRE

    Riaan Bredell; Jackie Walters

    2007-01-01

    Integrated supply chain risk management (ISCRM) has become indispensable to the theory and practice of supply chain management. The economic and political realities of the modern world require not only a different approach to supply chain management, but also bold steps to secure supply chain performance and sustainable wealth creation. Integrated supply chain risk management provides supply chain organisations with a level of insight into their supply chains yet to be achieved. If correctly ...

  12. Supply Chain Connectivity: Enhancing Participation in the Global Supply Chain

    OpenAIRE

    Patalinghug, Epictetus E.

    2015-01-01

    Supply chain connectivity is vital for the efficient flow of trade among APEC economies. This paper reviews the literature and supply chain management, describes the barriers to enhancing participation in global supply chain, analyzes the various measures of supply chain performance, and suggests steps for the Philippines to fully reap the benefits of the global value chain.

  13. Predicting the chemical stability of monatomic chains

    Science.gov (United States)

    Lin, Zheng-Zhe; Chen, Xi

    2013-02-01

    A simple model for evaluating the thermal atomic transfer rates in nanosystems (Lin Z.-Z. et al., EPL, 94 (2011) 40002) was developed to predict the chemical reaction rates of nanosystems with small gas molecules. The accuracy of the model was verified by MD simulations for molecular adsorption and desorption on a monatomic chain. By the prediction, a monatomic carbon chain should survive for 1.2 × 102 years in the ambient of 1 atm O2 at room temperature, and it is very invulnerable to N2, H2O, NO2, CO and CO2, while a monatomic gold chain quickly ruptures in vacuum. It is worth noting that since the model can be easily applied via common ab initio calculations, it could be widely used in the prediction of chemical stability of nanosystems.

  14. The electronic properties of a Fibonacci chain

    Directory of Open Access Journals (Sweden)

    S. A. Ketabi

    2004-12-01

    Full Text Available  Using a tight-binding model and transfer-matrix technique, as well as Lanczos algorithm, we numerically investigate the nature of the electronic states and electron transmission in site, bond and mixing Fibonacci model chains. We rely on the Landauer formalism as the basis for studying the conduction properties of these systems. Calculating the Lyapunov exponent, we also study the localization properties of electronic eigenstates in the Fibonacci chains. The focus is on the significance of the relationship between the transmission spectra and the nature of the electronic states. Our results show that, in contrast to Anderson’s localization theorem, in the Fibonacci chains the electronic states are non-localized and the transparent states occurr near the Fermi level.

  15. Understanding the supply chain

    Directory of Open Access Journals (Sweden)

    Aćimović Slobodan

    2006-01-01

    Full Text Available Supply chain management represents new business philosophy and includes strategically positioned and much wider scope of activity in comparison with its "older brother" - management of logistics. Philosophy of the concept of supply chain is directed to more coordination of key business functions of every link in distribution chain in the process of organization of the flow of both goods and information, while logistic managing instruments are focused on internal optimum of flows of goods and information within one company. Applying the concept of integrated supply chain among several companies makes the importance of operative logistics activity even greater on the level of one company, thus advancing processes of optimum and coordination within and between different companies and confirms the importance of logistics performances for the company’s profitability. Besides the fact that the borders between companies are being deleted, this concept of supply chain in one distribution channel influences increasing of importance of functional, i.e. traditional business managing approaches but instead it points out the importance of process managing approaches. Although the author is aware that "there is nothing harder, more dangerous and with uncertain success, but to find a way for introducing some novelties (Machiavelli, it would be even his additional stimulation for trying to bring closer the concept and goals of supply chain implementation that are identified in key, relevant, modern, theoretical and consulting approaches in order to achieve better understanding of the subject and faster implementation of the concept of supply chain management by domestic companies.

  16. 链转移剂单体存在下自由基NaSCN溶液聚合制备支化聚丙烯腈%Preparation of Branched Polyacrylonitrile via Free Radical Polymerization in NaSCN Solution with a Chain Transfer Monomer

    Institute of Scientific and Technical Information of China (English)

    张岩; 崔逸; 黄文艳; 薛小强; 杨宏军; 蒋必彪

    2014-01-01

    Branched polyacrylonitrile (BPAN) was prepared by traditional radical polymerization in the presence of 2-(3-mercaptopropionyloxy)ethyl methacrylate (MMPOE) as the chain transfer monomer. Vinyl acetate (VAc) was introduced as the second monomer, and the polymerization was initiated using 2,2'-azobisisobutyronitrile (AIBN) and carried out in 45% NaSCN solution. The influence of chain transfer monomer dosage on the copolymerization was investigated. Gas chromatography (GC), proton nuclear magnetic resonance (1H-NMR), triple-detection gel-permeation chromatography (TD-GPC), and rotation rheometer were used to determine the monomer conversion, molecular weight and viscosity of the resulted branched polymer. The results show that, PAN with high degree of branching was prepared and the degree of branching increases when the dosage of MMPOE increases, while the molecular weight decreases gradually with the increase of MMPOE dosage because of chain transfer reaction. The zero-shear viscosity of branched PAN solution with 15.7%solid content is only 12.7%of their linear counterpart with the same molecular weight at 25℃.%以偶氮二异丁腈(AIBN)为引发剂,醋酸乙烯酯(VAc)为第二单体,甲基丙烯酸-3-巯基丙酰氧基乙酯(MMPOE)为链转移剂单体,45%硫氰酸钠(NaSCN)水溶液为溶剂,进行常规自由基共聚反应合成支化聚丙烯腈(BPAN);研究了链转移剂单体含量对聚合物的影响。通过气相色谱(GC)、核磁共振氢谱(1H-NMR)、三检测凝胶渗透色谱(TD-GPC)、旋转流变仪分别对聚合反应过程和聚合产物进行了表征分析。结果表明:在NaSCN水溶液体系中,以MMPOE为链转移剂单体制得了较高支化程度的支化PAN,其支化程度随MMPOE含量的增加而提高,分子量随MMPOE含量的增加而降低;25℃下,15.7%固体含量的支化PAN溶液的零剪切黏度(η0=3.52 Pa·s)仅为其同分子量的线型聚合物溶液黏度(η0=27.7 Pa·s)的12.7%。

  17. "Transfer Shock" or "Transfer Ecstasy?"

    Science.gov (United States)

    Nickens, John M.

    The alleged characteristic drop in grade point average (GPA) of transfer students and the subsequent rise in GPA was investigated in this study. No statistically significant difference was found in first term junior year GPA between junior college transfers and native Florida State University students after the variance accounted for by the…

  18. Artificial radioisotopes in food chains

    International Nuclear Information System (INIS)

    Use of uranium for nuclear fission involves the risk of environmental contamination by radiation during the processes of mining, concentration, peaceful and military application and storage, reprocessing and waste disposal. Three of the most dangerous radioisotopes have been followed here as they move through four different food chains. The main bottlenecks for fast and massive transfer are for 131I its rather short half life, for 137Cs the defective plant uptake from soil (and much less so also the pathway through the animal body), and for 90Sr its discrimination relative to calcium in several transport processes in the animal body, and its preference for the bone mass. Hence it is often of advantage for man to use animals as an additional food chain. Known exceptions are discussed: the reindeer and karibou living entirely on lichens during the winter and thereby acquiring for 137Cs nearly identical specific activity as plant food, and cow's milk for iodine during a short period after contamination. 15 refs.; 1 figure; 4 tabs

  19. Radiocesium bioaccumulation in freshwater plankton: Influences of cation concentrations (K+ and Na+) on direct uptake of 137Cs in Chlamydomonas, Scenedesmus and Daphnia. Food-chain transfer of 137Cs from Chlamydomonas to Daphnia at different K+ concentrations

    International Nuclear Information System (INIS)

    magna were performed in order to address the influence of [K+] (ranging from 4.6 to 300 μM) on the direct uptake of 137CS from the water in the absence of contaminated food. In other experiments (performed at 4.6 and 300 μM K+), non-contaminated individuals of D. magna were transferred to Chlamydomonas cultures that had approached steady-state BCF in order to address the relative importance of the different uptake routes of 137CS in freshwater zooplankton. Both direct uptake and food consumption contributed significantly to radiocesium bioaccumulation in D. magna, and observed steady-state bioaccumulation factors (BAF) were generally 2 -10 times higher than Chlamydomonas BCFs at corresponding external [K+]. (au)

  20. Project Decision Chain

    DEFF Research Database (Denmark)

    Rolstadås, Asbjørn; Pinto, Jeffrey K.; Falster, Peter;

    2015-01-01

    To add value to project performance and help obtain project success, a new framework for decision making in projects is defined. It introduces the project decision chain inspired by the supply chain thinking in the manufacturing sector and uses three types of decisions: authorization, selection......, and plan decision. A primitive decision element is defined where all the three decision types can be accommodated. Each task in the primitive element can in itself contain subtasks that in turn will comprise new primitive elements. The primitive elements are nested together in a project decision chain....

  1. Practicality of spin chain wiring in diamond quantum technologies.

    Science.gov (United States)

    Ping, Yuting; Lovett, Brendon W; Benjamin, Simon C; Gauger, Erik M

    2013-03-01

    Coupled spin chains are promising candidates for wiring up qubits in solid-state quantum computing (QC). In particular, two nitrogen-vacancy centers in diamond can be connected by a chain of implanted nitrogen impurities; when driven by suitable global fields the chain can potentially enable quantum state transfer at room temperature. However, our detailed analysis of error effects suggests that foreseeable systems may fall far short of the fidelities required for QC. Fortunately the chain can function in the more modest role as a mediator of noisy entanglement, enabling QC provided that we use subsequent purification. For instance, a chain of 5 spins with interspin distances of 10 nm has finite entangling power as long as the T(2) time of the spins exceeds 0.55 ms. Moreover we show that repurposing the chain this way can remove the restriction to nearest-neighbor interactions, so eliminating the need for complicated dynamical decoupling sequences. PMID:23521240

  2. Customer-Driven Supply Chains From Glass Pipelines to Open Innovation Networks

    CERN Document Server

    Lyons, Andrew C; Piller, Frank; Poler, Raúl

    2012-01-01

    In recent years, the supply chain has become a key element to the survival and prosperity of organisations in different industry sectors. Organisations dealing in dynamic business environments demand supply chains that support the satisfaction of customer needs. The principles of lean thinking that once permeated standalone organisations have now been transferred to the supply chain, making imperative the development of innovative approaches to supply chain management.    Customer-Driven Supply Chains: From Glass Pipelines to Open Innovation Networks reviews the concept of lean thinking and its relationship to other key initiatives associated with supply chain management. Detailed industrial case studies based on the authors’ experience illustrate the principles behind lean supply chains. Moreover, a series of diagrams are used to illustrate critical concepts and supply chain architectures. Special emphasis is placed on the importance of transferring lean principles from the organisational level to the s...

  3. Editorial: Supply Chain Management

    Directory of Open Access Journals (Sweden)

    Aidonis, D.

    2012-01-01

    Full Text Available This special issue has followed up the 2nd Olympus International Conference on Supply Chains held on October 5-6, 2012, in Katerini, Greece. The Conference was organized by the Department of Logistics of Alexander Technological Educational Institution (ATEI of Thessaloniki, in collaboration with the Laboratory of Quantitative Analysis, Logistics and Supply Chain Management of the Department of Mechanical Engineering, Aristotle University of Thessaloniki (AUTH. During the 2-Days Conference more than 50 research papers were presented covering the following thematic areas: (i Business Logistics, (ii Transportation, Telematics and Distribution Networks, (iii Green Logistics, (iv Information and Communication Technologies in Supply Chain Management, and (v Services and Quality. Three keynote invited speakers addressed interesting issues for the Humanitarian Logistics, Green Supply Chains of the Agrifood Sector and the Opportunities and Prospects of Greek Ports chaired Round Tables with other Greek and Foreign Scientists and Specialists.

  4. Supply chain risk management

    Directory of Open Access Journals (Sweden)

    Christian Hollstein

    2013-03-01

    Full Text Available Background: Supply chain risk management increasingly gains prominence in many international industries. In order to strengthen supply chain structures, processes, and networks, adequate potentials for risk management need to be built (focus on effective logistics and to be utilized (focus on efficient logistics. Natural-based disasters, such as the case of Fukushima, illustrate how crucial risk management is. Method: By aligning a theoretical-conceptual framework with empirical-inductive findings, it may be hypothesized that logistical systems do have a positive effect on supply chain risk management activities.  Result/conclusion:  Flexibility and capacity, as well as redundancy and standardization, are often viewed as being conflictionary. It shows, however, that in the light of supply chain risk management, those factors may yield a common benefit if proper logistics systems are applied.  

  5. Supply chain reliability modelling

    OpenAIRE

    Eugen Zaitsev

    2012-01-01

    Background: Today it is virtually impossible to operate alone on the international level in the logistics business. This promotes the establishment and development of new integrated business entities - logistic operators. However, such cooperation within a supply chain creates also many problems related to the supply chain reliability as well as the optimization of the supplies planning. The aim of this paper was to develop and formulate the mathematical model and algorithms to find the ...

  6. Supply Chain Collaboration

    OpenAIRE

    Guy Rodrigue Ghomsi 1982

    2015-01-01

    Companies are now progressively looking beyond themselves to come up with ways to improve revenue and profit margins. This has resulted in a heightened focus on the efficiency of the supply chains. Inefficient supply chains are being perceived as cavities that can deprive the firm from its cash flows when inventory is not required and sales revenue when product is not available at the point of sales. This has stimulated development of business models that intend to leverage and enhance the su...

  7. Variance bounding Markov chains

    OpenAIRE

    Roberts, Gareth O.; Jeffrey S. Rosenthal

    2008-01-01

    We introduce a new property of Markov chains, called variance bounding. We prove that, for reversible chains at least, variance bounding is weaker than, but closely related to, geometric ergodicity. Furthermore, variance bounding is equivalent to the existence of usual central limit theorems for all L2 functionals. Also, variance bounding (unlike geometric ergodicity) is preserved under the Peskun order. We close with some applications to Metropolis–Hastings algorithms.

  8. Supply chain risk management

    OpenAIRE

    Christian Hollstein; Frank Himpel

    2013-01-01

    Background: Supply chain risk management increasingly gains prominence in many international industries. In order to strengthen supply chain structures, processes, and networks, adequate potentials for risk management need to be built (focus on effective logistics) and to be utilized (focus on efficient logistics). Natural-based disasters, such as the case of Fukushima, illustrate how crucial risk management is. Method: By aligning a theoretical-conceptual framework with empirical-induct...

  9. Editorial: Supply Chain Management

    OpenAIRE

    Aidonis, D.; Folinas, D.; Triantafillou, D.

    2012-01-01

    This special issue has followed up the 2nd Olympus International Conference on Supply Chains held on October 5-6, 2012, in Katerini, Greece. The Conference was organized by the Department of Logistics of Alexander Technological Educational Institution (ATEI) of Thessaloniki, in collaboration with the Laboratory of Quantitative Analysis, Logistics and Supply Chain Management of the Department of Mechanical Engineering, Aristotle University of Thessaloniki (AUTH). During the 2-Days Conference m...

  10. Innovation Across the Supply Chain

    DEFF Research Database (Denmark)

    Druehl, Cheryl; Carrillo, Janice; Hsuan, Juliana

    Innovation is an integral part of every firm’s ongoing operations. Beyond product innovation, supply chain innovations offer a unique source of competitive advantage. We synthesize recent research on innovation in the supply chain, specifically, innovative supply chain processes...

  11. MASTERING SUPPLY CHAIN RISKS

    Directory of Open Access Journals (Sweden)

    Borut Jereb

    2012-11-01

    Full Text Available Risks in supply chains represent one of the major business issues today. Since every organizationstrives for success and uninterrupted operations, efficient supply chain risk management is crucial.During supply chain risk research at the Faculty of Logistics in Maribor (Slovenia some keyissues in the field were identified, the major being the lack of instruments which can make riskmanagement in an organization easier and more efficient. Consequently, a model which captures anddescribes risks in an organization and its supply chain was developed. It is in accordance with thegeneral risk management and supply chain security standards, the ISO 31000 and ISO 28000families. It also incorporates recent finding from the risk management field, especially from theviewpoint of segmenting of the public.The model described in this paper focuses on the risks itself by defining them by different keydimensions, so that risk management is simplified and can be undertaken in every supply chain andorganizations within them. Based on our mode and consequent practical research in actualorganizations, a freely accessible risk catalog has been assembled and published online from the risksthat have been identified so far. This catalog can serve as a checklist and a starting point in supplychain risk management in organizations. It also incorporates experts from the field into a community,in order to assemble an ever growing list of possible risks and to provide insight into the model andits value in practice.

  12. The Relationship between Organizational Transfer Climate and Positive Transfer of Training.

    Science.gov (United States)

    Rouiller, Janice Z; Goldstein, Irwin L.

    1993-01-01

    After a 9-week training course, 102 manager trainees in a fast-food chain were assigned to restaurants. Those assigned to units having positive organizational transfer climate (measured by situational cues and consequences) were rated as better performers. Climate affected the degree to which learned behavior was transferred to the actual job. (SK)

  13. Research on Knowledge-Oriented Supply ChainRisk Management System Model

    OpenAIRE

    Yingchun Guo

    2011-01-01

    Based on analyzing the characteristics of supply chain risk management under the influences of knowledge, in this paper integrates basic theories and methods of knowledge management into the process of risk management, builds a knowledge-oriented supply chain risk management system model, and proposes relevant strategies, presenting references for practical application of knowledge-oriented supply chain risk management. By means of acquiring, storing, sharing, and transferring supply chain ri...

  14. A Formal Model of Trust Chain based on Multi-level Security Policy

    Directory of Open Access Journals (Sweden)

    Kong Xiangying

    2013-07-01

    Full Text Available Trust chain is the core technology of trusted computing. A formal model of trust chain based on finite state automata theory is proposed. We use communicating sequential processes to describe the system state transition in trust chain and by combining with multi-level security strategy give the definition of trust system and trust decision theorem of trust chain transfer which is proved meantime. Finally, a prototype system is given to show the efficiency of the model.

  15. Issues on Supply Chain Management

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Although supply chain is regarded as an integrated pr ocess, actually, researchers and practitioners have primarily investigated the v arious processes of the supply chain individually. The competitive field in most markets requires well-designed integrated supply chain instead of individual o perations. In this paper, some traditional thinking of supply chain is given fir st, then SCM (Supply Chain Management) is introduced, which views the entire sup ply chain as a whole rather than individual process a...

  16. A 2-chain can interlock with a k-chain

    OpenAIRE

    Glass, Julie; Langerman, Stefan; O'Rourke, Joseph; Snoeyink, Jack; Zhong, Jianyuan K.

    2004-01-01

    One of the open problems posed in [3] is: what is the minimal number k such that an open, flexible k-chain can interlock with a flexible 2-chain? In this paper, we establish the assumption behind this problem, that there is indeed some k that achieves interlocking. We prove that a flexible 2-chain can interlock with a flexible, open 16-chain.

  17. 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.

  18. Research on the Logistics Supply Chain in Port Logistics Transportation

    OpenAIRE

    Wang Yan-liang

    2013-01-01

    The aim of this study is to improve and increase the logistics system effectiveness and to solve the problem of optimal movement of different flows. Logistics transport carrying the world on material resources transfer exchange important mission and economic development and our lives are closely linked, logistics chain logistics transport occupies an important position and in the e logistics chain in port logistics has play a decisive role. For many coastal countries port logistics is the eco...

  19. Phasic Triplet Markov Chains.

    Science.gov (United States)

    El Yazid Boudaren, Mohamed; Monfrini, Emmanuel; Pieczynski, Wojciech; Aïssani, Amar

    2014-11-01

    Hidden Markov chains have been shown to be inadequate for data modeling under some complex conditions. In this work, we address the problem of statistical modeling of phenomena involving two heterogeneous system states. Such phenomena may arise in biology or communications, among other fields. Namely, we consider that a sequence of meaningful words is to be searched within a whole observation that also contains arbitrary one-by-one symbols. Moreover, a word may be interrupted at some site to be carried on later. Applying plain hidden Markov chains to such data, while ignoring their specificity, yields unsatisfactory results. The Phasic triplet Markov chain, proposed in this paper, overcomes this difficulty by means of an auxiliary underlying process in accordance with the triplet Markov chains theory. Related Bayesian restoration techniques and parameters estimation procedures according to the new model are then described. Finally, to assess the performance of the proposed model against the conventional hidden Markov chain model, experiments are conducted on synthetic and real data. PMID:26353069

  20. A 2-chain can interlock with an open 10-chain

    OpenAIRE

    Lu, Bin; O'Rourke, Joseph; Zhong, Jianyuan K.

    2013-01-01

    It is an open problem, posed in \\cite{SoCG}, to determine the minimal $k$ such that an open flexible $k$-chain can interlock with a flexible 2-chain. It was first established in \\cite{GLOSZ} that there is an open 16-chain in a trapezoid frame that achieves interlocking. This was subsequently improved in \\cite{GLOZ} to establish interlocking between a 2-chain and an open 11-chain. Here we improve that result once more, establishing interlocking between a 2-chain and a 10-chain. We present argu...

  1. Facilitating Transfers

    DEFF Research Database (Denmark)

    Kjær, Poul F.

    The concept of governance has mutated into an all‐embracing buzz‐word characterised by a low degree of conceptual precision and empirical focus. This paper therefore suggests a narrower and more precise understanding of governance and the regulatory function it fulfils by advancing the argument t...... and different types of transfers between them. It will, furthermore, explore the role and “quality” of different types of regulatory governance frameworks in relation to the facilitation, stabilisation and justification of transfers....... that the essential functional and normative purpose of regulatory governance is to facilitate, stabilise and justify the transfer of condensed social components (such as economic capital and products, political decisions, legal judgements, religious beliefs and scientific knowledge) from one social contexts...

  2. Report on tool transfer and alignment methods

    DEFF Research Database (Denmark)

    Tosello, Guido; Gasparin, Stefania; De Grave, Arnaud;

    2010-01-01

    In the last few years, research work has been carried out regarding the feature miniaturization and tooling performance achievable with specific process chains combining different micro machining processes. On the other hand, technologies, strategies and tool design rules in order to optimize...... the accuracy of the hybrid tooling process chain with a focus on the part transfer and re-position of different machining chains have not been addressed thoroughly and are the topic of Task 2.2.3 “Tool transfer for hybrid manufacturing”. First results are presented in this report, focussing on a specific...... process chain for tooling (i.e. hybrid tooling) based on the combination of micro milling and micro electrical discharge machining (EDM) milling, both at machine tool and at machining technology levels....

  3. State transfer in intrinsic decoherence spin channels

    CERN Document Server

    Hu, Ming-Liang; 10.1140/epjd/e2009-00220-8

    2011-01-01

    By analytically solving the master equation, we investigate quantum state transfer, creation and distribution of entanglement in the model of Milburn's intrinsic decoherence. Our results reveal that the ideal spin channels will be destroyed by the intrinsic decoherence environment, and the detrimental effects become severe as the decoherence rate $\\gamma$ and the spin chain length $N$ increase. For infinite evolution time, both the state transfer fidelity and the concurrence of the created and distributed entanglement approach steady state values, which are independent of the decoherence rate $\\gamma$ and decrease as the spin chain length $N$ increases. Finally, we present two modified spin chains which may serve as near perfect spin channels for long distance state transfer even in the presence of intrinsic decoherence environments $\\mathcal {F}{[\\rho(t)]}$.

  4. Blastocyst Transfer

    OpenAIRE

    sprotocols

    2014-01-01

    ### Method: Blastocyst transfer is usually performed 24 hours after aggregation when the morulae have become expanded blastocysts and on the same day as injection. A little time is given between injection and transfer to allow blastocysts to re-expand. **The Recipient** Careful selection of the recipient is most important as the pups are the end result of a lot of hard work. Two strains of mice are used:RB Swiss and (CBA*C57BL6/J)f1. RB Swiss are quiet and make excellent mothers ...

  5. Heat transfer

    CERN Document Server

    Holman, J P

    2010-01-01

    As one of the most popular heat transfer texts, Jack Holman's "Heat Transfer" is noted for its clarity, accessible approach, and inclusion of many examples and problem sets. The new tenth edition retains the straight-forward, to-the-point writing style while covering both analytical and empirical approaches to the subject. Throughout the book, emphasis is placed on physical understanding while, at the same time, relying on meaningful experimental data in those situations that do not permit a simple analytical solution. New examples and templates provide students with updated resources for computer-numerical solutions.

  6. Supply chain quality management

    Directory of Open Access Journals (Sweden)

    Hannan Amoozad Mahdiraji

    2012-10-01

    Full Text Available In recent years, there are several methods introduced for the improvement of operational performances. Total quality management and supply chain management are two methods recommended for this purpose. These two approaches have been studied in most researches separately, while they have objectives in common, and this makes them a strategic means, which can be used, simultaneously. Total quality management and supply chain management play significant roles to increase the organizational competitiveness power. Moreover, they have only one purpose that is customer satisfaction, and they are different only on their approaches to reach their objectives. In this research, we aim to study both approaches of quality management and supply chain, their positive increasing effects that may be generated after their integration. For this purpose, the concept and definitions of each approach is studied, independently, their similarities and differences are recognized, and finally, the advantages of their integration are introduced.

  7. Environmental Retail Supply Chains

    DEFF Research Database (Denmark)

    Kotzab, Herbert; Munch, Hilde; de Faultrier, Birgitte;

    2011-01-01

    been undertaken through an investigative approach applying a web-scan framework which included the analysis of web sites and publicly published documents such as annual reports and corporate social responsibility reports. Findings – The authors identified 34 environmental sustainability initiatives......Purpose – The purpose of this paper is to develop a scale that evaluates the environmental elements in retail supply chains and to examine the environmental supply chain management initiatives of the world's largest 100 retailing companies. Design/methodology/approach – The empirical evaluation has...... which were grouped into eight categories; they refer to “fundamental environmental attitude”, “use of energy”, “use of input material”, “product”, “packaging”, “transport”, “consumption” and “waste”. The level of environmental supply chain management can be characterised as very operational and very...

  8. Supply-Chain Optimization Template

    Science.gov (United States)

    Quiett, William F.; Sealing, Scott L.

    2009-01-01

    The Supply-Chain Optimization Template (SCOT) is an instructional guide for identifying, evaluating, and optimizing (including re-engineering) aerospace- oriented supply chains. The SCOT was derived from the Supply Chain Council s Supply-Chain Operations Reference (SCC SCOR) Model, which is more generic and more oriented toward achieving a competitive advantage in business.

  9. Essentials of supply chain management

    CERN Document Server

    Hugos, Michael H

    2011-01-01

    The latest thinking, strategies, developments, and technologies to stay current in supply chain management Presenting the core concepts and techniques of supply chain management in a clear, concise and easily readable style, the Third Edition of Essentials of Supply Chain Management outlines the most crucial tenets and concepts of supply chain management.

  10. Building the resilient supply chain.

    OpenAIRE

    Christopher, Martin; Peck, Helen

    2004-01-01

    In today’s uncertain and turbulent markets, supply chain vulnerability has become an issue of significance for many companies. As supply chains become more complex as a result of global sourcing and the continued trend to ‘leaning-down’, supply chain risk increases. The challenge to business today is to manage and mitigate that risk through creating more resilient supply chains.

  11. METRODOS: Meteorological preprocessor chain

    DEFF Research Database (Denmark)

    Astrup, P.; Mikkelsen, T.; Deme, S.

    2001-01-01

    The METRODOS meteorological preprocessor chain combines measured tower data and coarse grid numerical weather prediction (NWP) data with local scale flow models and similarity scaling to give high resolution approximations of the meteorological situation. Based on available wind velocity...... - heat flux related measurement, e.g. a temperature gradient, are used to give local values of friction velocity and Monin-Obukhov length plus an estimate of the mixing height. The METRODOS meteorological preprocessor chain is an integral part of the RODOS - Real Time On Line Decision Support - program...

  12. Integrated supply chain risk management

    Directory of Open Access Journals (Sweden)

    Riaan Bredell

    2007-11-01

    Full Text Available Integrated supply chain risk management (ISCRM has become indispensable to the theory and practice of supply chain management. The economic and political realities of the modern world require not only a different approach to supply chain management, but also bold steps to secure supply chain performance and sustainable wealth creation. Integrated supply chain risk management provides supply chain organisations with a level of insight into their supply chains yet to be achieved. If correctly applied, this process may optimise management decision-making and assist in the protection and enhancement of shareholder value.

  13. Technology transfer

    International Nuclear Information System (INIS)

    This paper emphasizes in the specific areas of design, engineering and component production. This paper presents what Framatome has to offer in these areas and its export oriented philosophy. Then, a typical example of this technology transfer philosophy is the collaboration with the South Korean firm, Korea Heavy Industries Corporation (KHIC) for the supply of KNU 9 and KNU 10 power stations

  14. Sophisticated transfer

    NARCIS (Netherlands)

    Reinhart, T.

    2006-01-01

    On the eve of the Iraq war, fears were expressed in different circles that under the cover of war, Israel may attempt a transfer of Palestinians in the “seam line” area of the northern West Bank (Kalkilya, Tulkarem). Last week, the army produced a scene from this scenario. On April 2 at 3 AM, a larg

  15. Preventing Hg Transference from Soil to Terrestrial Food Chain

    Institute of Scientific and Technical Information of China (English)

    QINGCHANG-LE; MOUSHU-SEN

    1993-01-01

    Hg in acid soil could be activited by liming and become available to plant,if excessive or insufficient amount of line was applied.The changes of Hg activity in acid soil with different rates of CaCO3 amendment were studied by a pot experiment.To predict the adequate amount of lime application,a simple method using the pH(EDTA) as an indicator was suggested.The suitable range of lime application was the amount of lime addition when the pH of soil-EDTA system was raised to 4.0-4.3.

  16. 技术转移视角下全产业链创新网络的行为模式:融合创新--以苹果公司网络为例%Behavior Patterns Based on Technology Transfer of the Innovation Networks of Whole Industry Chain is Integration and Innovation, Apple's Network as an Example

    Institute of Scientific and Technical Information of China (English)

    黄磊; 刘则渊; 姜照华

    2014-01-01

    Based on the practical implications of characterization of variables on network self-citation rate and cita-tions within the network, behavior patterns of innovation networks of whole industry chain and core business in network is integration and innovation of internal and external technical. Behavior characteristic, way flow of knowl-edge of based on technology transfer and operation mechanism and linkages of micro and macro levels to be ana-lyzed. Dominant behavior patterns of innovation networks and core business is innovation patterns based on exter-nal technology. According to autoregressive distributed lag model (ardl), characterization of behavioral variables on since number of patents cited of network and number of patents cited in the network is a lag effect for total number of patents of network. According to method of least squares, regression analysis of three variables is sig-nificant. According to the above analysis, behavior patterns of innovation networks of whole industry chain are in-tegration and innovation of significant.%研究了根据网络自引率和网络内引用率表征的实际含义,得出全产业链创新网络和网络内核心企业的行为模式:外部技术和内部技术相融合的融合创新模式。分析了融合创新行为模式的特性、基于技术转移的知识流动方式与微观和宏观两个层次的运行机理和相互联系。得到创新网络和核心企业的主导行为模式均为基于外部技术的创新模式。根据自回归分布滞后模型得出了网络自引专利数和网络内引用专利数所表征的行为对网络总专利数滞后效应。根据最小二乘法对三变量回归具有显著性,得出全产业链创新网络具有显著的融合创新行为模式的结论。

  17. Development Value Chains meet Business Supply Chains : The concept of Global Value Chains unraveled

    NARCIS (Netherlands)

    S. Drost (Sarah); J.C.A.C. van Wijk (Jeroen); S. Vellema (Sietze)

    2011-01-01

    textabstractValue chain promotion is considered a key element of private sector development strategies and pro-poor growth. However, (value) chain concepts are rather complex and unclear. This paper unravels the concept of global value chains and studies the diversity of key value chain-related (sup

  18. Economy, market and chain

    NARCIS (Netherlands)

    Sukkel, W.; Hommes, M.

    2009-01-01

    In their pursuit of growth and professionalisation, the Dutch organic sector focuses primarily on market development. But how do you stimulate the market for organic foods? This is the subject of many research projects concerning market, consumer preferences and the supply chain. These projects focu

  19. Plastic value chains

    DEFF Research Database (Denmark)

    Baxter, John; Wahlstrom, Margareta; Zu Castell-Rüdenhausen, Malin;

    2014-01-01

    Optimizing plastic value chains is regarded as an important measure in order to increase recycling of plastics in an efficient way. This can also lead to improved awareness of the hazardous substances contained in plastic waste, and how to avoid that these substances are recycled. As an example...

  20. Innovation in Supply Chains

    DEFF Research Database (Denmark)

    Maier, Maximilian; Korbel, Jakob; Brem, Alexander

    2015-01-01

    . Moreover, along with the fourth industrial revolution – industry 4.0 – new technologies such as cyber physical systems are fast gaining popularity. Hence, based on the analysis of relevant literature, we further develop the supply chain committee model, developed by Kaluza et al. (2003) to demonstrate how...

  1. Shared Value Chain Design

    DEFF Research Database (Denmark)

    Bals, Lydia; Tate, Wendy L.

    In Sustainable Supply Chain Management (SSCM) research still the classic economic perspective is the dominating perspective, although the triple bottom line (including economic, social and ecological) is well accepted. The theoretical foundation for the paper is Stakeholder Theory. Case studies o...

  2. Sustainable Supply Chain Design

    DEFF Research Database (Denmark)

    Bals, Lydia; Tate, Wendy

    A significant conceptual and practical challenge is how to integrate triple bottom line (TBL; including economic, social and environmental) sustainability into global supply chains. Although this integration is necessary to slow down global resource depletion, understanding is limited of how to i...

  3. CHAINE DES ROTISSEUR @ HILTON

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    The annual gala dinner of Chaine des Rotisseurs was hosted by Hilton Beijing. The “Ballet Dinner” - a great creation for both art and fine dining lovers was taken place in varies places within the hotel, including hotel lobby, 3rd floor and lobby lounge.

  4. Exploration Supply Chain Simulation

    Science.gov (United States)

    2008-01-01

    The Exploration Supply Chain Simulation project was chartered by the NASA Exploration Systems Mission Directorate to develop a software tool, with proper data, to quantitatively analyze supply chains for future program planning. This tool is a discrete-event simulation that uses the basic supply chain concepts of planning, sourcing, making, delivering, and returning. This supply chain perspective is combined with other discrete or continuous simulation factors. Discrete resource events (such as launch or delivery reviews) are represented as organizational functional units. Continuous resources (such as civil service or contractor program functions) are defined as enabling functional units. Concepts of fixed and variable costs are included in the model to allow the discrete events to interact with cost calculations. The definition file is intrinsic to the model, but a blank start can be initiated at any time. The current definition file is an Orion Ares I crew launch vehicle. Parameters stretch from Kennedy Space Center across and into other program entities (Michaud Assembly Facility, Aliant Techsystems, Stennis Space Center, Johnson Space Center, etc.) though these will only gain detail as the file continues to evolve. The Orion Ares I file definition in the tool continues to evolve, and analysis from this tool is expected in 2008. This is the first application of such business-driven modeling to a NASA/government-- aerospace contractor endeavor.

  5. Supply chain reliability modelling

    Directory of Open Access Journals (Sweden)

    Eugen Zaitsev

    2012-03-01

    Full Text Available Background: Today it is virtually impossible to operate alone on the international level in the logistics business. This promotes the establishment and development of new integrated business entities - logistic operators. However, such cooperation within a supply chain creates also many problems related to the supply chain reliability as well as the optimization of the supplies planning. The aim of this paper was to develop and formulate the mathematical model and algorithms to find the optimum plan of supplies by using economic criterion and the model for the probability evaluating of non-failure operation of supply chain. Methods: The mathematical model and algorithms to find the optimum plan of supplies were developed and formulated by using economic criterion and the model for the probability evaluating of non-failure operation of supply chain. Results and conclusions: The problem of ensuring failure-free performance of goods supply channel analyzed in the paper is characteristic of distributed network systems that make active use of business process outsourcing technologies. The complex planning problem occurring in such systems that requires taking into account the consumer's requirements for failure-free performance in terms of supply volumes and correctness can be reduced to a relatively simple linear programming problem through logical analysis of the structures. The sequence of the operations, which should be taken into account during the process of the supply planning with the supplier's functional reliability, was presented.

  6. Standard handbook of chains chains for power transmission and material handling

    CERN Document Server

    Chain Association, American

    2005-01-01

    A BRIEF HISTORY OF THE DEVELOPMENT OF CHAINEarly DevelopmentsCog ChainCast Detachable ChainCast Pintle ChainPrecision Roller ChainEngineering Steel ChainSilent ChainFlat-Top ChainTerminologyA CHAIN OVERVIEW: USES AND ADVANTAGESGeneralTypes of ChainScope of Chains CoveredStyles and Forms of ChainsStraight and Offset Link ChainsChains With and Without RollersUses of ChainStandard Chains and Their UsesThe Advantages of Chains in ApplicationsAdvantages of Roller Chains in DrivesAdvantages of Silent Chain Drives

  7. An RFID middleware for supply chain management

    Directory of Open Access Journals (Sweden)

    Artur Pinto Carneiro

    2011-12-01

    Full Text Available RFID (Radio Frequency Identification systems for identification and tracking of products and equipments have been progressively adopted as an essential tool for supply chain management, a production environment where the members usually share with each other their own logistic and management systems. Therefore, the development of supply chain RFID systems can be strongly simplified through the inclusion of an intermediate software layer – the middleware – responsible for the creation of interfaces to integrate all the heterogeneous software components. In this article we present a case study developed at IPT (Instituto de Pesquisas Tecnológicas do Estado de São Paulo which gave rise to a middleware prototype able to implement the required software integration on the supply chain of an electric power distribution company. The developed middleware is used to manage the interactions with a heterogeneous group of mobile devices  cell phones, handhelds and data colectors,  operated by different supply chain agents that grab data associated to various processes executed by a given electric power distribution equipment during its life cycle and transfer those data to a central database in order to share them with all the logistic and management corporation systems.

  8. Magnetocaloric effect in ferroelectric Ising chain magnet

    Science.gov (United States)

    Qi, Yan; Liu, Jia; Yu, Nai-sen; Du, An

    2016-05-01

    We investigate the magnetocaloric effect (MCE) in multiferroic chain system by adopting the elastic Ising-chain model. Based on the transfer-matrix method, the magnetothermal quantities of characterizing MCE behaviors including the entropy, entropy change and adiabatic cooling rate are rigorously determined. Combined with analysis of ground-state, we mainly discuss results in an antiferromagnetic regime associated with ferroelectric transition. Our results show that the entropy change is greatly enhanced near the saturation field as frustration parameter varies in this regime, and accompanied with remarkable inverse MCE, indicating the enormous potential of multiferroic system in low-temperature refrigeration. Meanwhile we also observe a prominent temperature variation in the isoentropy curves close to zero-temperature ferroelectric transition, but this enhancing MCE signal is very sensitive to the thermal fluctuations, and can be strongly suppressed even under a small temperature.

  9. Putative respiratory chain of Porphyromonas gingivalis.

    Science.gov (United States)

    Meuric, Vincent; Rouillon, Astrid; Chandad, Fatiha; Bonnaure-Mallet, Martine

    2010-05-01

    The electron transfer chain in Porphyromonas gingivalis, or periodontopathogens, has not yet been characterized. P. gingivalis, a strict anaerobic bacteria and the second colonizer of the oral cavity, is considered to be a major causal agent involved in periodontal diseases. Primary colonizers create a favorable environment for P. gingivalis growth by decreasing oxygen pressure. Oxygen does not appear to be the final electron acceptor of the respiratory chain. Fumarate and cytochrome b have been implicated as major components of the respiratory activity. However, the P. gingivalis genome shows many other enzymes that could be implicated in aerobic or nitrite respiration. Using bioinformatic tools and literature studies of respiratory pathways, the ATP synthesis mechanism from the sodium cycle and nutrients metabolism, the putative respirasome of P. gingivalis has been proposed.

  10. Intermuscular force transmission along myofascial chains: a systematic review.

    Science.gov (United States)

    Krause, Frieder; Wilke, Jan; Vogt, Lutz; Banzer, Winfried

    2016-06-01

    The present review aims to provide a systematic overview on tensile transmission along myofascial chains based on anatomical dissection studies and in vivo experiments. Evidence for the existence of myofascial chains is growing, and the capability of force transmission via myofascial chains has been hypothesized. However, there is still a lack of evidence concerning the functional significance and capability for force transfer. A systematic literature research was conducted using MEDLINE (Pubmed), ScienceDirect and Google Scholar. Studied myofascial chains encompassed the superficial backline (SBL), the back functional line (BFL) and the front functional line (FFL). Peer-reviewed human dissection studies as well as in vivo experiments reporting intermuscular tension transfer between the constituents of a myofascial chain were included. To assess methodic quality, two independent investigators rated studies by means of validated assessment tools (QUACS and PEDro Scale). The literature research identified 1022 articles. Nine studies (moderate to excellent methodological quality) were included. Concerning the SBL and the BFL, there is moderate evidence for force transfer at all three transitions (based on six studies), and one of two transitions (three studies). One study yields moderate evidence for a slight, but not significant force transfer at one transition in the FFL. The findings of the present study indicate that tension can be transferred between some of the examined adjacent structures. Force transfer might have an impact in overuse conditions as well as on sports performance. However, different methods of force application and measurement hinder the comparability of results. Considering anatomical variations in the degree of continuity and histological differences of the linking structures is crucial for interpretation. Future studies should focus on the in vivo function of myofascial continuity during isolated active or passive tissue tensioning.

  11. Intermuscular force transmission along myofascial chains: a systematic review.

    Science.gov (United States)

    Krause, Frieder; Wilke, Jan; Vogt, Lutz; Banzer, Winfried

    2016-06-01

    The present review aims to provide a systematic overview on tensile transmission along myofascial chains based on anatomical dissection studies and in vivo experiments. Evidence for the existence of myofascial chains is growing, and the capability of force transmission via myofascial chains has been hypothesized. However, there is still a lack of evidence concerning the functional significance and capability for force transfer. A systematic literature research was conducted using MEDLINE (Pubmed), ScienceDirect and Google Scholar. Studied myofascial chains encompassed the superficial backline (SBL), the back functional line (BFL) and the front functional line (FFL). Peer-reviewed human dissection studies as well as in vivo experiments reporting intermuscular tension transfer between the constituents of a myofascial chain were included. To assess methodic quality, two independent investigators rated studies by means of validated assessment tools (QUACS and PEDro Scale). The literature research identified 1022 articles. Nine studies (moderate to excellent methodological quality) were included. Concerning the SBL and the BFL, there is moderate evidence for force transfer at all three transitions (based on six studies), and one of two transitions (three studies). One study yields moderate evidence for a slight, but not significant force transfer at one transition in the FFL. The findings of the present study indicate that tension can be transferred between some of the examined adjacent structures. Force transfer might have an impact in overuse conditions as well as on sports performance. However, different methods of force application and measurement hinder the comparability of results. Considering anatomical variations in the degree of continuity and histological differences of the linking structures is crucial for interpretation. Future studies should focus on the in vivo function of myofascial continuity during isolated active or passive tissue tensioning. PMID

  12. The design of supply chains

    DEFF Research Database (Denmark)

    Bøge Sørensen, Lars

    2004-01-01

    Keywords Supply Chain Management, Supply Chain Design, Literature studyAbstract Argues stability is a design objective for supply chain design alongside cost, leadtime and responsiveness. Performs an extensive literature study on supply chain design,identifies methods, theories and objectives...... in the existing literature. Describes the conceptexternal specificity and how it's used to design supply chains. Using the concept upstream,archetypes of risk minimal and maximal design are identified. Downstream the conceptdescribes two viable scenarios, one minimizing the impact, the other minimizing...... theprobability of (intended) departure of a supply chain partner. Finally, principles for supplychain design are described and managerial outlined....

  13. Decision-Making for Supply Chain Integration Supply Chain Integration

    CERN Document Server

    Lettice, Fiona; Durowoju, Olatunde

    2012-01-01

    Effective supply chain integration, and the tight co-ordination it creates, is an essential pre-requisite for successful supply chain management.  Decision-Making for Supply Chain Integration is a practical reference on recent research in the area of supply chain integration focusing on distributed decision-making problems. Recent applications of various decision-making tools for integrating supply chains are covered including chapters focusing on: •Supplier selection, pricing strategy and inventory decisions in multi-level supply chains, •RFID-enabled distributed decision-making, •Operational risk issues and time-critical decision-making for sensitive logistics nodes, Modelling end to end processes to improve supply chain integration, and •Integrated systems to improve service delivery and optimize resource use. Decision-Making for Supply Chain Integration provides an insight into the tools and methodologies of this field with support from real-life case studies demonstrating successful application ...

  14. Respiratory electron transfer in Escherichia coli : components, energetics and regulation

    OpenAIRE

    Hellingwerf, K.J.; Teixeira De Mattos, M.J.; Bekker, M.

    2009-01-01

    The respiratory chain that is housed in the bacterial cytoplasmic membrane, generally transfers electrons from NADH to oxygen; in the absence of oxygen it can use several alternative electron acceptors, such as nitrate and fumarate. Transfer of electrons through this chain is usually coupled to the translocation of protons across the membrane. The resulting gradient of protons is then used for the generation of ATP by the F0F1-ATPase, and for other free energy requiring processes such as solu...

  15. Heavy chain only antibodies

    DEFF Research Database (Denmark)

    Moghimi, Seyed Moein; Rahbarizadeh, Fatemeh; Ahmadvand, Davoud;

    2013-01-01

    Unlike conventional antibodies, heavy chain only antibodies derived from camel contain a single variable domain (VHH) and two constant domains (CH2 and CH3). Cloned and isolated VHHs possess unique properties that enable them to excel conventional therapeutic antibodies and their smaller antigen-...... for combating HER2+ breast cancer. © 2013 by Tabriz University of Medical Sciences.......Unlike conventional antibodies, heavy chain only antibodies derived from camel contain a single variable domain (VHH) and two constant domains (CH2 and CH3). Cloned and isolated VHHs possess unique properties that enable them to excel conventional therapeutic antibodies and their smaller antigen......-binding fragments in cancer targeting and therapy. VHHs express low immunogenicity, are highly robust and easy to manufacture and have the ability to recognize hidden or uncommon epitopes. We highlight the utility of VHH in design of new molecular, multifunctional particulate and immune cell-based systems...

  16. Perioperative supply chain management.

    Science.gov (United States)

    Feistritzer, N R; Keck, B R

    2000-09-01

    Faced with declining revenues and increasing operating expenses, hospitals are evaluating numerous mechanisms designed to reduce costs while simultaneously maintaining quality care. Many facilities have targeted initial cost reduction efforts in the reduction of labor expenses. Once labor expenses have been "right sized," facilities have continued to focus on service delivery improvements by the optimization of the "supply chain" process. This report presents a case study of the efforts of Vanderbilt University Medical Center in the redesign of its supply chain management process in the department of Perioperative Services. Utilizing a multidisciplinary project management structure, 3 work teams were established to complete the redesign process. To date, the project has reduced costs by $2.3 million and enhanced quality patient care by enhancing the delivery of appropriate clinical supplies during the perioperative experience.

  17. Volumes of chain links

    CERN Document Server

    Kaiser, James; Rollins, Clint

    2011-01-01

    Agol has conjectured that minimally twisted n-chain links are the smallest volume hyperbolic manifolds with n cusps, for n at most 10. In his thesis, Venzke mentions that these cannot be smallest volume for n at least 11, but does not provide a proof. In this paper, we give a proof of Venzke's statement. The proof for n at least 60 is completely rigorous. The proof for n between 11 and 59 uses a computer calculation, and can be made rigorous for manifolds of small enough complexity, using methods of Moser and Milley. Finally, we prove that the n-chain link with 2m or 2m+1 half-twists cannot be the minimal volume hyperbolic manifold with n cusps, provided n is at least 60 or |m| is at least 8, and we give computational data indicating this remains true for smaller n and |m|.

  18. Towards Intelligent Supply Chains

    DEFF Research Database (Denmark)

    Siurdyban, Artur; Møller, Charles

    2012-01-01

    of deploying inapt operations leading to deterioration of profits. To address this problem, we propose a unified business process design framework based on the paradigm of intelligence. Intelligence allows humans and human-designed systems cope with environmental volatility, and we argue that its principles...... applied to the context of organizational processes can increase the success rate of business operations. The framework is created using a set of theoretical based constructs grounded in a discussion across several streams of research including psychology, pedagogy, artificial intelligence, learning......, business process management and supply chain management. It outlines a number of system tasks combined in four integrated management perspectives: build, execute, grow and innovate, put forward as business process design propositions for Intelligent Supply Chains....

  19. Demand chain management-integrating marketing and supply chain management

    OpenAIRE

    Jüttner, Uta; Christopher, Martin; Baker, Susan

    2007-01-01

    This paper endorses demand chain management as a new business model aimed at creating value in today's marketplace, and combining the strengths of marketing and supply chain competencies. Demand chain design is based on a thorough market understanding and has to be managed in such a way as to effectively meet differing customer needs. Based on a literature review as well as the findings from a co-development workshop and focus group discussions with marketing and supply chain professionals, a...

  20. Spin Chains and Chiral Lattice Fermions

    CERN Document Server

    Thacker, H B

    1995-01-01

    The generalization of Lorentz invariance to solvable two-dimensional lattice fermion models has been formulated in terms of Baxter's corner transfer matrix. In these models, the lattice Hamiltonian and boost operator are given by fermionized nearest-neighbor Heisenberg spin chain operators. The transformation properties of the local lattice fermion operators under a boost provide a natural and precise way of generalizing the chiral structure of a continuum Dirac field to the lattice. The resulting formulation differs from both the Wilson and staggered (Kogut-Susskind) prescriptions. In particular, an axial $Q_5$ rotation is sitewise local, while the vector charge rotation mixes nearest neighbors on even and odd sublattices.

  1. Supply Chain Initiatives Database

    Energy Technology Data Exchange (ETDEWEB)

    None

    2012-11-01

    The Supply Chain Initiatives Database (SCID) presents innovative approaches to engaging industrial suppliers in efforts to save energy, increase productivity and improve environmental performance. This comprehensive and freely-accessible database was developed by the Institute for Industrial Productivity (IIP). IIP acknowledges Ecofys for their valuable contributions. The database contains case studies searchable according to the types of activities buyers are undertaking to motivate suppliers, target sector, organization leading the initiative, and program or partnership linkages.

  2. Input chains and industrialization

    OpenAIRE

    Ciccone, Antonio

    2000-01-01

    A key aspect of industrialization is the adoption of increasing-returns-to-scale, industrial, technologies. Two other, well-documented aspects are that industrial technologies are adopted throughout intermediate-input chains and that they use intermediate inputs intensively relative to the technologies they replace. These features of industrial technologies combined imply that countries with access to similar technologies may have very different levels of industrial...

  3. Inclusive Global Value Chains

    OpenAIRE

    Cusolito, Ana Paula; Safadi, Raed; Taglioni, Daria

    2016-01-01

    This report's focus is making global value chains (GVCs) more inclusive. To achieve inclusiveness is by overcoming participation constraints for Small and Medium Enterprises (SMEs) and facilitation access for Low Income Developing Countries (LIDCs). The underlying assumption is that most firms in LIDCs are SMEs. Even larger firms in LIDCs are likely to face similar challenges to SMEs, including a less supportive domestic operating environment and weaker institutions that lead to higher fixed ...

  4. Polymerase chain reaction

    OpenAIRE

    Gaurav Solanki

    2015-01-01

    The polymerase chain reaction (PCR) is a technique in molecular biology to amplify a single or a few copies of a piece of DNA across several orders of magnitude, generating thousands to millions of copies of a particular DNA sequence. PCR is now a common and often indispensable technique used in medical and biological research labs for a variety of applications. There are three major steps involved in the PCR technique: denaturation, annealing and extension. PCR is useful in the investigation...

  5. The innovation value chain.

    Science.gov (United States)

    Hansen, Morten T; Birkinshaw, Julian

    2007-06-01

    The challenges of coming up with fresh ideas and realizing profits from them are different for every company. One firm may excel at finding good ideas but may have weak systems for bringing them to market. Another organization may have a terrific process for funding and rolling out new products and services but a shortage of concepts to develop. In this article, Hansen and Birkinshaw caution executives against using the latest and greatest innovation approaches and tools without understanding the unique deficiencies in their companies' innovation systems. They offer a framework for evaluating innovation performance: the innovation value chain. It comprises the three main phases of innovation (idea generation, conversion, and diffusion) as well as the critical activities performed during those phases (looking for ideas inside your unit; looking for them in other units; looking for them externally; selecting ideas; funding them; and promoting and spreading ideas companywide). Using this framework, managers get an end-to-end view of their innovation efforts. They can pinpoint their weakest links and tailor innovation best practices appropriately to strengthen those links. Companies typically succumb to one of three broad "weakest-link" scenarios. They are idea poor, conversion poor, or diffusion poor. The article looks at the ways smart companies - including Intuit, P&G, Sara Lee, Shell, and Siemens- modify the best innovation practices and apply them to address those organizations' individual needs and flaws. The authors warn that adopting the chain-based view of innovation requires new measures of what can be delivered by each link in the chain. The approach also entails new roles for employees "external scouts" and "internal evangelists," for example. Indeed, in their search for new hires, companies should seek out those candidates who can help address particular weaknesses in the innovation value chain.

  6. Tax efficient supply chain

    OpenAIRE

    Borralho, Joana Patrícia Costeira

    2014-01-01

    Master of Science in Business Administration. This case started with the following question: How supply chains and tax policy interact? This question was the starting point for this study and was developed under the areas of Logistics and International Tax Policy. In order to support this study, the adopted methodology was the selection of a Multinational company – LPR Portugal – which has the transportation and distribution in the European Union as a scope of service and...

  7. Port supply chain integration : analyzing biofuel supply chains

    NARCIS (Netherlands)

    Stevens, Leonie C. E.; Vis, Iris F. A.

    2016-01-01

    This paper focuses on port supply chain integration to strengthen operational and business performance. We provide a structured and comprehensive method to enable port supply chain integration and demonstrate its applicability to the biofuel supply chain. We define the value proposition, role, activ

  8. Hyperinflation in the Ising model on quasiperiodic chains

    Science.gov (United States)

    Odagaki, T.

    1990-02-01

    Using a hyperinflation rule, the free energy of the two component Ising system on a chain with an arbitrary quasiperiodic order is shown to be given by an average of the free energy of each component, in agreement with the result obtained by the transfer matrix formalism.

  9. Perfluorooctane sulphonate (PFOS) throughout the food production chain

    NARCIS (Netherlands)

    Asselt, van E.D.; Rietra, R.P.J.J.; Romkens, P.F.A.M.; Fels-Klerx, van der H.J.

    2011-01-01

    Perfluorooctane sulphonate (PFOS) is a persistent organic pollutant with adverse effects on human health. Since dietary intake plays an important role in human exposure, the transfer of PFOS throughout the food chain needs further investigation. The aim of this paper is to give an overview of PFOS c

  10. moisture transfer

    Directory of Open Access Journals (Sweden)

    Don Kulasiri

    2005-01-01

    model drying porous materials. Coupled partial differential equations governing the moisture and heat transfer can be solved using numerical techniques, and in this paper we solve them analytically in a setting suitable for industrial drying situations. We discuss the nature of the solutions using the physical properties of Pinus radiata. It is shown that the temperature gradients play a significant role in deciding the moisture profiles within the material when thickness is large and that models based only on moisture potential gradients may not be sufficient to explain the drying phenomena in moist porous materials.

  11. Historiographical transfers

    Directory of Open Access Journals (Sweden)

    Jacques-Emmanuel Bernard

    2008-06-01

    Full Text Available “There are other signs that the Greeks began to notice the peculiarities of Roman social life and of Roman behavior in international affairs. True enough, the famous set of Roman values – fides, constantia, severitas, auctoritas, etc., – was discovered for the first time by German professors during the First World War, and helped their pupils to mark time while Hitler was deciding what to do with the classics”.Arnoldo Momigliano, Alien Wisdom. For anyone interested in the transfer of historio...

  12. Heat transfer

    CERN Document Server

    Jorge, Kubie; Thomas, Grassie

    2012-01-01

    A core task of engineers is to analyse energy related problems. The analytical treatment is usually based on principles of thermodynamics, fluid mechanics and heat transfer, but is increasingly being handled computationally.This unique resource presents a practical textbook, written for both undergraduates and professionals, with a series of over 60 computer workbooks on an accompanying CD.The book emphasizes how complex problems can be deconstructed into a series of simple steps. All thermophysical property computations are illustrated using diagrams within text and on the compani

  13. Adjustable Chain Trees for Proteins

    DEFF Research Database (Denmark)

    Winter, Pawel; Fonseca, Rasmus

    2012-01-01

    A chain tree is a data structure for changing protein conformations. It enables very fast detection of clashes and free energy potential calculations. A modified version of chain trees that adjust themselves to the changing conformations of folding proteins is introduced. This results in much...... tighter bounding volume hierarchies and therefore fewer intersection checks. Computational results indicate that the efficiency of the adjustable chain trees is significantly improved compared to the traditional chain trees....

  14. Supply chain dynamics in Asia

    OpenAIRE

    Banomyong, Ruth

    2010-01-01

    Supply chain management in Asia is a relatively novel topic but a key challenge for all Asian based manufacturers and traders when trying to integrate into the "global market". The purpose of the paper is to describe key supply chain issues faced in Asia. These issues are related to supply chain security that forces Asian firms to comply with numerous requirements as well as the importance of a properly managed supply chain in enhancing firms' competitiveness. The critical role played by Asia...

  15. Ernst Chain: a great man of science.

    Science.gov (United States)

    Kardos, Nelson; Demain, Arnold L

    2013-08-01

    This paper is a tribute to the scientific accomplishments of Ernst Chain and the influence he exerted over the fields of industrial microbiology and biotechnology. Chain is the father of the modern antibiotic era and all the benefits that these therapeutic agents have brought, i.e., longer life spans, greater levels of public health, widespread modern surgery, and control of debilitating infectious diseases, including tuberculosis, gonorrhea, syphilis, etc. Penicillin was the first antibiotic to become commercially available, and its use ushered in the age of antibiotics. The discovery of penicillin's bactericidal action had been made by Alexander Fleming in London in 1928. After publishing his observations in 1929, no further progress was made until the work was picked up in 1939 by scientists at Oxford University. The group was headed by Howard Florey, and Chain was the group's lead scientist. Chain was born and educated in Germany, and he fled in 1933 as a Jewish refugee from Nazism to England. Other important members of the Oxford research team were Norman Heatley and Edward Abraham. The team was able to produce and isolate penicillin under conditions of scarce resources and many technical challenges. Sufficient material was collected and tested on mice to successfully demonstrate penicillin's bactericidal action on pathogens, while being nontoxic to mammals. Chain directed the microbiological methods for producing penicillin and the chemical engineering methods to extract the material. This technology was transferred to US government facilities in 1941 for commercial production of penicillin, becoming an important element in the Allied war effort. In 1945, the Nobel Prize for medicine was shared by Fleming, Florey, and Chain in recognition of their work in developing penicillin as a therapeutic agent. After World War II, Chain tried to persuade the British government to fund a new national antibiotic industry with both research and production facilities. As

  16. Requirements of supply chain management in differentiating European pork chains.

    Science.gov (United States)

    Trienekens, Jacques; Wognum, Nel

    2013-11-01

    This paper summarizes results obtained by research into pork chain management in the EU Integrated Project Q-Porkchains. Changing demands for intrinsic and extrinsic quality attributes of pork products impact the way supply chain management should be organized from the farmer down to the consumer. The paper shows the importance of Quality Management Systems for integrating supply chains and enhancing consumer confidence. The paper also presents innovations in information system integration for aligning information exchange in the supply chain and logistics concepts based on innovative measurement technologies at the slaughterhouse stage. In the final section research challenges towards sustainable pork supply chains satisfying current consumer demands are presented. PMID:23611335

  17. Requirements of supply chain management in differentiating European pork chains.

    Science.gov (United States)

    Trienekens, Jacques; Wognum, Nel

    2013-11-01

    This paper summarizes results obtained by research into pork chain management in the EU Integrated Project Q-Porkchains. Changing demands for intrinsic and extrinsic quality attributes of pork products impact the way supply chain management should be organized from the farmer down to the consumer. The paper shows the importance of Quality Management Systems for integrating supply chains and enhancing consumer confidence. The paper also presents innovations in information system integration for aligning information exchange in the supply chain and logistics concepts based on innovative measurement technologies at the slaughterhouse stage. In the final section research challenges towards sustainable pork supply chains satisfying current consumer demands are presented.

  18. Risk Management in Logystics Chains

    OpenAIRE

    Butrin, Andrey; Vikulov, Vladimir

    2013-01-01

    Article is devoted to risk management of supply chain. The authors considered indicators of supply chain risks, including risks caused by supplier. Authors formed a method of optimizing the level of supply chain risk in the integration with suppliers and customers.

  19. Designing structural supply chain flexibility

    NARCIS (Netherlands)

    Mulinski, Ksawery Jan

    2012-01-01

    In a continuously changing business environment the role of supply chain flexibility is constantly increasing. A flexible supply chain can ensure survival in quickly changing market conditions as well as enable sustainable growth. This thesis explores the topic of supply chain flexibility with focus

  20. Academic Education Chain Operation Model

    OpenAIRE

    Ruskov, Petko; Ruskov, Andrey

    2007-01-01

    This paper presents an approach for modelling the educational processes as a value added chain. It is an attempt to use a business approach to interpret and compile existing business and educational processes towards reference models and suggest an Academic Education Chain Operation Model. The model can be used to develop an Academic Chain Operation Reference Model.

  1. On chains of centered valuations

    Directory of Open Access Journals (Sweden)

    Rachid Chibloun

    2003-01-01

    Full Text Available We study chains of centered valuations of a domain A and chains of centered valuations of A [X1,…,Xn] corresponding to valuations of A. Finally, we make some applications to chains of valuations centered on the same ideal of A [X1,…,Xn] and extending the same valuation of A.

  2. Exact solution of the D3 non-Abelian anyon chain

    Science.gov (United States)

    Braylovskaya, Natalia; Finch, Peter E.; Frahm, Holger

    2016-08-01

    Commuting transfer matrices for linear chains of interacting non-Abelian anyons from the two-dimensional irreducible representation of the dihedral group D3 [or, equivalently, the integer sector of the s u (2) 4 spin-1 chain] are constructed using the spin-anyon correspondence to a D3-symmetric formulation of the XXZ Heisenberg spin chain. The spectral problem is solved using discrete inversion identities satisfied by these transfer matrices and functional Bethe ansatz methods. The resulting spectrum can be related to that of the XXZ spin-1/2 Heisenberg chain with boundary conditions depending on the topological sector of the anyon chain. The properties of this model in the critical regime are studied by finite size analysis of the spectrum. In particular, points in the phase diagram where the anyon chain realizes some of the rational Z2 orbifold theories are identified.

  3. Exact solution of the $D_3$ non-Abelian anyon chain

    CERN Document Server

    Braylovskaya, Natalia; Frahm, Holger

    2016-01-01

    Commuting transfer matrices for linear chains of interacting non-Abelian anyons from the two-dimensional irreducible representation of the dihedral group $D_3$ (or, equivalently, the integer sector of the $su(2)_4$ spin-$1$ chain) are constructed using the spin-anyon correspondence to a $D_3$-symmetric formulation of the XXZ Heisenberg spin chain. The spectral problem is solved using discrete inversion identities satisfied by these transfer matrices and functional Bethe ansatz methods. The resulting spectrum can be related to that of the XXZ spin-$1/2$ Heisenberg chain with boundary conditions depending on the topological sector of the anyon chain. The properties of this model in the critical regime are studied by finite size analysis of the spectrum. In particular, points in the phase diagram where the anyon chain realizes some of the rational $\\mathbb{Z}_2$ orbifold theories are identified.

  4. Coupled motions direct electrons along human microsomal P450 Chains.

    Directory of Open Access Journals (Sweden)

    Christopher R Pudney

    2011-12-01

    Full Text Available Protein domain motion is often implicated in biological electron transfer, but the general significance of motion is not clear. Motion has been implicated in the transfer of electrons from human cytochrome P450 reductase (CPR to all microsomal cytochrome P450s (CYPs. Our hypothesis is that tight coupling of motion with enzyme chemistry can signal "ready and waiting" states for electron transfer from CPR to downstream CYPs and support vectorial electron transfer across complex redox chains. We developed a novel approach to study the time-dependence of dynamical change during catalysis that reports on the changing conformational states of CPR. FRET was linked to stopped-flow studies of electron transfer in CPR that contains donor-acceptor fluorophores on the enzyme surface. Open and closed states of CPR were correlated with key steps in the catalytic cycle which demonstrated how redox chemistry and NADPH binding drive successive opening and closing of the enzyme. Specifically, we provide evidence that reduction of the flavin moieties in CPR induces CPR opening, whereas ligand binding induces CPR closing. A dynamic reaction cycle was created in which CPR optimizes internal electron transfer between flavin cofactors by adopting closed states and signals "ready and waiting" conformations to partner CYP enzymes by adopting more open states. This complex, temporal control of enzyme motion is used to catalyze directional electron transfer from NADPH→FAD→FMN→heme, thereby facilitating all microsomal P450-catalysed reactions. Motions critical to the broader biological functions of CPR are tightly coupled to enzyme chemistry in the human NADPH-CPR-CYP redox chain. That redox chemistry alone is sufficient to drive functionally necessary, large-scale conformational change is remarkable. Rather than relying on stochastic conformational sampling, our study highlights a need for tight coupling of motion to enzyme chemistry to give vectorial electron

  5. Targeting gene transfer to ovarian epithelial carcinoma cells with lentivirus displaying single-chain antibody%单链抗体导向卵巢上皮癌进行靶向基因 转移的实验研究

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Objective:To investigate the targeting gene transfer of Anti-MUC-1(ScFv) directed lentivirus to MUC-1+ ovarian epithelial carcinoma cells.Methods:MUC-1 single-chain antibody gene constructed in the plasmid pM.TC.G were transferred to packaging cell line 293T to produce anti-MUC-1-directed lentivirus using Ca3(PO4)2 precipitation method. Ovarian epithelial cancer cell line SKOV-3(MUC-1+) and normal human gingival fibroblast cell GF(MUC-1-)were co-cultured, then were infected by lentivirus. The infection result was observed through fluorescence microscopy. The competition assay that was the addition of the anti-MUC-1 single-chain antibody prior to lentivirus infection showed whether anti-MUC-1 Ab could inhibite infection. Results: After lentivirus infetion, cell SKOV-3 and GF which were co-cultured had remarkably different infection rate. The addition of the MUC-1 Ab prior to the lentivirus infection showed anti-MUC-1 Ab can inhibite infection.This competition assay showed that the infection is mediated by the antibody moiety and, therefore, is antibody specific. Conclusions:Anti-MUC-1(ScFv) directed lentivirus can targetingly transfer gene into MUC-1+ ovarian cancer cell line.%目的:探讨靶向性基因转移载体—含抗MUC-1单链抗体的慢病毒对MUC-1+卵巢上皮癌细胞系SKOV-3细胞进行基因转移的特异性,为卵巢上皮癌的靶向性基因治疗提供实验基础。方法:将针对SKOV-3细胞上抗原MUC-1的单链抗体基因构建到慢病毒包膜结构质粒(pM.TC.G),以报告基因绿色荧光蛋白(GFP)基因作为目的基因。用磷酸钙沉淀法进行Anti-MUC-1(ScFv)慢病毒包装,感染共培养的卵巢癌细胞SKOV-3(MUC-1+)和正常人成纤维细胞GF(MUC-1-),荧光显微镜下观察感染效果。竞争抑制实验即病毒感染前加入Anti-MUC-1单抗是否抑制病毒感染。结果:荧光显微镜下观察到Anti-MUC-1(ScFv)介导的慢病毒对共培养的SKOV-3(MUC-1+

  6. Radiology's value chain.

    Science.gov (United States)

    Enzmann, Dieter R

    2012-04-01

    A diagnostic radiology value chain is constructed to define its main components, all of which are vulnerable to change, because digitization has caused disaggregation of the chain. Some components afford opportunities to improve productivity, some add value, while some face outsourcing to lower labor cost and to information technology substitutes, raising commoditization risks. Digital image information, because it can be competitive at smaller economies of scale, allows faster, differential rates of technological innovation of components, initiating a centralization-to-decentralization technology trend. Digitization, having triggered disaggregation of radiology's professional service model, may soon usher in an information business model. This means moving from a mind-set of "reading images" to an orientation of creating and organizing information for greater accuracy, faster speed, and lower cost in medical decision making. Information businesses view value chain investments differently than do small professional services. In the former model, producing a better business product will extend image interpretation beyond a radiologist's personal fund of knowledge to encompass expanding external imaging databases. A follow-on expansion with integration of image and molecular information into a report will offer new value in medical decision making. Improved interpretation plus new integration will enrich and diversify radiology's key service products, the report and consultation. A more robust, information-rich report derived from a "systems" and "computational" radiology approach will be facilitated by a transition from a professional service to an information business. Under health care reform, radiology will transition its emphasis from volume to greater value. Radiology's future brightens with the adoption of a philosophy of offering information rather than "reads" for decision making. Staunchly defending the status quo via turf wars is unlikely to constitute a

  7. Analytical Bethe ansatz for the open AdS/CFT SU(1|1) spin chain

    CERN Document Server

    Nepomechie, Rafael I

    2008-01-01

    We prove an inversion identity for the open AdS/CFT SU(1|1) quantum spin chain which is exact for finite size. We use this identity, together with an analytic ansatz, to determine the eigenvalues of the transfer matrix and the corresponding Bethe ansatz equations. We also solve the closed chain by algebraic Bethe ansatz.

  8. Musical Markov Chains

    Science.gov (United States)

    Volchenkov, Dima; Dawin, Jean René

    A system for using dice to compose music randomly is known as the musical dice game. The discrete time MIDI models of 804 pieces of classical music written by 29 composers have been encoded into the transition matrices and studied by Markov chains. Contrary to human languages, entropy dominates over redundancy, in the musical dice games based on the compositions of classical music. The maximum complexity is achieved on the blocks consisting of just a few notes (8 notes, for the musical dice games generated over Bach's compositions). First passage times to notes can be used to resolve tonality and feature a composer.

  9. Excitation energy transfer in the photosystem I

    Energy Technology Data Exchange (ETDEWEB)

    Webber, Andrew N

    2012-09-25

    Photosystem I is a multimeric pigment protein complex in plants, green alage and cyanobacteria that functions in series with Photosystem II to use light energy to oxidize water and reduce carbon dioxide. The Photosystem I core complex contains 96 chlorophyll a molecules and 22 carotenoids that are involved in light harvesting and electron transfer. In eucaryotes, PSI also has a peripheral light harvesting complex I (LHCI). The role of specific chlorophylls in excitation and electron transfer are still unresolved. In particular, the role of so-called bridging chlorophylls, located between the bulk antenna and the core electron transfer chain, in the transfer of excitation energy to the reaction center are unknown. During the past funding period, site directed mutagenesis has been used to create mutants that effect the physical properties of these key chlorophylls, and to explore how this alters the function of the photosystem. Studying these mutants using ultrafast absorption spectroscopy has led to a better understanding of the process by which excitation energy is transferred from the antenna chlorophylls to the electron transfer chain chlorophylls, and what the role of connecting chlorophylls and A_0 chlorophylls is in this process. We have also used these mutants to investigate whch of the central group of six chlorophylls are involved in the primary steps of charge separation and electron transfer.

  10. Inventory Control in Supply Chain Through Lateral Transshipment – A Case Study in Indian Industry

    OpenAIRE

    Dharamvir Mangal; Pankaj Chandna

    2009-01-01

    Supply chain management emphasizes collaborative relationships between supply chain members. The purpose of this work is to examine the antecedents of retailer - retailer partnership and to explore its impact on the supply chain performance. We consider coordination among stocking locations through replenishment strategies that take explicitly into consideration transshipments, transfer of a product among locations at the same echelon level. A continuous review inventory system has been adopt...

  11. A CryptoCubic Protocol for Hacker-Proof Off-Chain Bitcoin Transactions

    OpenAIRE

    Apeltsin, Leonard

    2014-01-01

    Off-Chain transactions allow for the immediate transfer of Cryptocurrency between two parties, without delays or unavoidable transaction fees. Such capabilities are critical for mainstream Cryptocurrency adaption. They allow for the "Coffee-Coin Criteria"; under which a customer orders a coffee and pays for that coffee in bitcoins. This is not possible with On-Chain transactions today. Unfortunately, all existing Off-Chain transaction protocols are notoriously unreliable The current generatio...

  12. Longwall AFC chain tension measurement

    Energy Technology Data Exchange (ETDEWEB)

    Lugg, P.; Guan, Z.; Pienaar, B.

    2009-10-01

    CRC Mining has developed a chain tension meter to measure the AFC chain tension during the operation. The device was certified Ex ia IP55 by SIMTARS for use in hazardous areas. In June 2007 this device was successfully trialled in an Australian longwall face. The trial was run monitoring AFC chain tensions over a few shifts. The dynamic behaviour and unequal sharing of load between the chains were recorded and found to be significant. During this trial the robustness of the tension meter electronics and protection housing was demonstrated, the measurement of AFC chain tensions on a working face can be achieved reliably. 2 refs., 14 figs.

  13. Failures in combined knowledge and material supply chains

    DEFF Research Database (Denmark)

    Koch, Christian

    2005-01-01

    by configuration by project. In such a setting creating value for the customers and the enterprises becomes dependent of the ability to organise and coordinate in the supply chains. That the configuration is not always successful can be demonstrated by studying the emergence of failures occurring in the supply......-month observation period. These were compiled and analysed. The economic consequences are calculated to be 8% of the production costs. The analysis of relations in the supply chain both shows relations to materials and knowledge chains and their interaction. Most of the failures were generated in the knowledge...... stream and then occasionally transfer into the material stream. The paper proposes initiatives to strengthen partnerships in supply chains and especially at engineer to order production. The contradiction between the permanent enterprise organisation potentially capable of handling purchasing...

  14. Analysis of a complex shape chain plate using Transmission Photoelasticity

    Science.gov (United States)

    Dasari, N.; Ramesh, K.

    2010-06-01

    Most chains are an assembly [1] of five parts namely, outer plate, inner plate, bush, pin and roller. Two inner plates are press fitted with two bushes to form an inner block assembly. The outer plates are press fitted with pins after keeping the pins through the assembled bushes of the inner block. Roller is a rotating member and placed over the bush during inner block assembly. Inner block assembly is the load transfer member from sprocket tooth. The outer block assembly helps in holding and also to pull the inner block over the sprocket teeth. If a chain length is in odd number of pitches, it requires an offset plate as shown in Figure 1 to connect two ends of the chain together to make chain endless. When the chain is assembled with an offset plate, the chain fatigue life was observed only 20 to 25% of the total life of a chain, assembled without an offset plate. The holes in the offset plate are of the same size as in the outer and inner plates respectively and it is a complex in shape chain plate. A inbuilt thinning zone at the centre of the chain plate as shown in Figure 1 is unavoidable. The stresses and its distribution in this complex shape chain plate geometry play a critical role in the fatigue life performance of a chain assembly. However, it is difficult identify the stress distribution and stress concentration zones precisely using only the conventional industrial friendly tools such as routine quality control test, breaking load test and numerical computations. In this context the transmission photoelastic technique has made it possible to identify the stress distribution, its concentration and also to quantify the stress and strain [2-3] at any point in the chain plate. This paper explains how transmission photoelastic technique is used to estimate the stress distribution and its concentration zones in a complex chain plate when it isloaded. An epoxy chain plate model was made through the casting method using a Perspex mould [2-3]. A loading

  15. Modeling Uncertainty of Directed Movement via Markov Chains

    Directory of Open Access Journals (Sweden)

    YIN Zhangcai

    2015-10-01

    Full Text Available Probabilistic time geography (PTG is suggested as an extension of (classical time geography, in order to present the uncertainty of an agent located at the accessible position by probability. This may provide a quantitative basis for most likely finding an agent at a location. In recent years, PTG based on normal distribution or Brown bridge has been proposed, its variance, however, is irrelevant with the agent's speed or divergent with the increase of the speed; so they are difficult to take into account application pertinence and stability. In this paper, a new method is proposed to model PTG based on Markov chain. Firstly, a bidirectional conditions Markov chain is modeled, the limit of which, when the moving speed is large enough, can be regarded as the Brown bridge, thus has the characteristics of digital stability. Then, the directed movement is mapped to Markov chains. The essential part is to build step length, the state space and transfer matrix of Markov chain according to the space and time position of directional movement, movement speed information, to make sure the Markov chain related to the movement speed. Finally, calculating continuously the probability distribution of the directed movement at any time by the Markov chains, it can be get the possibility of an agent located at the accessible position. Experimental results show that, the variance based on Markov chains not only is related to speed, but also is tending towards stability with increasing the agent's maximum speed.

  16. Polyketide chain length control by chain length factor.

    Science.gov (United States)

    Tang, Yi; Tsai, Shiou-Chuan; Khosla, Chaitan

    2003-10-22

    Bacterial aromatic polyketides are pharmacologically important natural products. A critical parameter that dictates product structure is the carbon chain length of the polyketide backbone. Systematic manipulation of polyketide chain length represents a major unmet challenge in natural product biosynthesis. Polyketide chain elongation is catalyzed by a heterodimeric ketosynthase. In contrast to homodimeric ketosynthases found in fatty acid synthases, the active site cysteine is absent from the one subunit of this heterodimer. The precise role of this catalytically silent subunit has been debated over the past decade. We demonstrate here that this subunit is the primary determinant of polyketide chain length, thereby validating its designation as chain length factor. Using structure-based mutagenesis, we identified key residues in the chain length factor that could be manipulated to convert an octaketide synthase into a decaketide synthase and vice versa. These results should lead to novel strategies for the engineered biosynthesis of hitherto unidentified polyketide scaffolds.

  17. Multidimensional Structure for Definingthe Effect of Organizational Culture and Supply Chain Culture on Knowledge Sharing in Supply Chain of Automotive Industry: With Emphasis on Improving Supply Chain Performance

    Directory of Open Access Journals (Sweden)

    Mohsen Shafiei Nikabadi

    2012-12-01

    Full Text Available : One of the key aspects of knowledge management is organizational culture. Finding an appropriate culture and key indicators for culture in implementation and execution of knowledge management are one the most important matter in knowledge management implementation in any organization. So, the main purpose of this article was presenting a multidimensional structure for organizational culture and supply chain culture with the aim of effective knowledge sharing in supply chain of automotive industry of Iran. First, according to the literature review, key indicators for any dimension of multidimensional structure of the research were defined. Then, key indicators were revised, adjusted and modified by three industry experts and three college professors, so 4 questions and 5 hypotheses were offered. Next, that multidimensional structure has been assessed as a survey and cause-effect study in supply chains of Iran Khodro Company and Saipa Company.115 industry professionals have participated in this study. In the research, after testing co-linearity between variables, relations between different dimensions of the multidimensional structure have been assessed with the help of path analysis. Research findings showed that the multidimensional structure introduced in the study had an appropriate fitness in automotive industry. The results of path analysis also showed that the culture of the supply chain has had the greatest impact of Business culture. On the other hand, business culture had a strong but indirect effect on supply chain performance. And finally, the greatest effect of knowledge sharing and transferring was on non-financial performance of supply chain.

  18. Evidence of rapid transfer and bioaccumulation of Microcystin-LR poses potential risk to freshwater prawn Macrobrachium rosenbergii (de Man)

    DEFF Research Database (Denmark)

    Liu, Liping; Su, Xiaoming; Chen, Taoying;

    2016-01-01

    Microcystins accumulate in aquatic organisms and can be transferred to higher trophic levels, eventually affecting vector animals and consumers. We examined three levels of an aquatic food chain (Microcystis aeruginosa, Daphnia magna and Macrobrachium rosenbergii) to identify the transfer...

  19. Doping of Semiconducting Atomic Chains

    Science.gov (United States)

    Toshishige, Yamada; Kutler, Paul (Technical Monitor)

    1997-01-01

    Due to the rapid progress in atom manipulation technology, atomic chain electronics would not be a dream, where foreign atoms are placed on a substrate to form a chain, and its electronic properties are designed by controlling the lattice constant d. It has been shown theoretically that a Si atomic chain is metallic regardless of d and that a Mg atomic chain is semiconducting or insulating with a band gap modified with d. For electronic applications, it is essential to establish a method to dope a semiconducting chain, which is to control the Fermi energy position without altering the original band structure. If we replace some of the chain atoms with dopant atoms randomly, the electrons will see random potential along the chain and will be localized strongly in space (Anderson localization). However, if we replace periodically, although the electrons can spread over the chain, there will generally appear new bands and band gaps reflecting the new periodicity of dopant atoms. This will change the original band structure significantly. In order to overcome this dilemma, we may place a dopant atom beside the chain at every N lattice periods (N > 1). Because of the periodic arrangement of dopant atoms, we can avoid the unwanted Anderson localization. Moreover, since the dopant atoms do not constitute the chain, the overlap interaction between them is minimized, and the band structure modification can be made smallest. Some tight-binding results will be discussed to demonstrate the present idea.

  20. Internal electron transfer within mitochondrial succinate-cytochrome C reductase

    International Nuclear Information System (INIS)

    Internal electron transfer within succinate-cytochrome C reductase from pigeon breast muscle mitochondria was followed by the pulse radiolytic technique. The electron equivalent is transferred from an unknown donor to b type cytochrome(s), in a first order process with a rate constant of: 660 +- 150s-1. This process might be the rate determining step of electron transfer in mitochondria, since it is similar in rate to the turnover number of the mitochondrial respiratory chain

  1. Quantum state transfer via temporal kicking of information

    CERN Document Server

    Di Franco, C; Kim, M S

    2009-01-01

    We propose a strategy for perfect state transfer in spin chains based on the use of an unmodulated coupling Hamiltonian whose coefficients are explicitly time dependent. We show that, if specific and non-demanding conditions are satisfied by the temporal behavior of the coupling strengths, our model allows perfect state transfer. The paradigma put forward by our proposal holds the promises to set an alternative standard to the use of clever encoding and coupling-strength engineering for perfect state transfer.

  2. Technology Transfer

    Science.gov (United States)

    Bullock, Kimberly R.

    1995-01-01

    The development and application of new technologies in the United States has always been important to the economic well being of the country. The National Aeronautics and Space Administration (NASA) has been an important source of these new technologies for almost four decades. Recently, increasing global competition has emphasized the importance of fully utilizing federally funded technologies. Today NASA must meet its mission goals while at the same time, conduct research and development that contributes to securing US economic growth. NASA technologies must be quickly and effectively transferred into commercial products. In order to accomplish this task, NASA has formulated a new way of doing business with the private sector. Emphasis is placed on forming mutually beneficial partnerships between NASA and US industry. New standards have been set in response to the process that increase effectiveness, efficiency, and timely customer response. This summer I have identified potential markets for two NASA inventions: including the Radially Focused Eddy Current Sensor for Characterization of Flaws in Metallic Tubing and the Radiographic Moire. I have also worked to establish a cooperative program with TAG, private industry, and a university known as the TAG/Industry/Academia Program.

  3. Polymerase Chain Reaction

    Directory of Open Access Journals (Sweden)

    Gaurav Solanki

    2012-10-01

    Full Text Available The polymerase chain reaction (PCR is a technique in molecular biology to amplify a single or a few copies of a piece of DNA across several orders of magnitude, generating thousands to millions of copies of a particular DNA sequence. PCR is now a common and often indispensable technique used in medical and biological research labs for a variety of applications. There are three major steps involved in the PCR technique: denaturation, annealing and extension. PCR is useful in the investigation and diagnosis of a growing number of diseases. PCR is also used in forensics laboratories. PCR can identify genes that have been implicated in the development of cancer. The present paper is an attempt to review basics of PCR in relation to its methods, application and use.

  4. Supply chain reaction

    International Nuclear Information System (INIS)

    'Logic' (Leading Oil and Gas Industry Competitiveness) is a government-industry supply chain management initiative which aims to improve the competitiveness of the UK's North Sea business by 1 billion UK pounds by 2002 and its export performance by 50% inside 5 years. Much of the article is devoted to the background and views of Logic's chief executive Chris. Freeman. Freeman makes clear that 'unlike Crine, we are not a cost-reduction initiative: that may be one of the outcomes, but we are really focusing on the co-operation side of things'. Logic aims to change the culture of the UK offshore industry through example. Freeman believes that the creation of collaborative success will flag up industry and give credence to Logics objectives

  5. PHONONS IN POLYACENIC CHAINS

    Institute of Scientific and Technical Information of China (English)

    O. Rafil; M. Tamine; B. Bourahla; R. Tigrine; S. Amoudache; A. Khater

    2006-01-01

    We have theoretically resolved phonon excitations in quasi-two-dimensional organic crystals of polyacenic semiconductor material which may be obtained by the pyrolytic treatment of phenol-formaldehyde resin. A model for studying the dynamical properties using three polyacene chains is proposed with the aim to present the vibrational properties of this structure. It employs the formalism of solid states in two dimensions which admit phonons. A simulation process of the two-dimensional lattice structure shows that elastic waves may explain the existence of vibrational modes in the frequency range 100-400 cm-1. The presence of acoustic and optical like phonons is discussed in terms of the elastic force constants. A hyperfine resonance structure is obtained. It allows the analysis of the dynamical evolution in thin films of polyacene. It is found that the behavior of the phonon density of states exhibits resonance between modes in the structure.

  6. The Bullwhip Effect: Concretization of Entropic Information Dissipation in Supply Chain Systems

    Directory of Open Access Journals (Sweden)

    Tarik Saikouk

    2012-08-01

    Full Text Available Supply chains represent complex and dynamic systems that incorporate autonomous firms interacting with one another to fulfill a common goal, while insuring their own ones. These firms’ behaviors are considered to be non-linear and sometimes unpredictable. This makes information transfer in the supply chain complex and causes instability when information transferred is incomplete or incorrect. This instability is characterized by the Bullwhip Effect that represents concretization of entropy, namely the degree of disorder within a system. In this paper we develop a new analytical approach assuming that the bullwhip effect is a consequence of the entropy of the supply chain system that is represented by information dissipation.

  7. Bethe ansatz for an AdS/CFT open spin chain with non-diagonal boundaries

    CERN Document Server

    Zhang, Xin; Cui, Shuai; Nepomechie, Rafael I; Yang, Wen-Li; Shi, Kangjie; Wang, Yupeng

    2015-01-01

    We consider the integrable open-chain transfer matrix corresponding to a Y=0 brane at one boundary, and a Y_theta=0 brane (rotated with the respect to the former by an angle theta) at the other boundary. We determine the exact eigenvalues of this transfer matrix in terms of solutions of a corresponding set of Bethe equations.

  8. Bethe Ansatz from functional relations of open XXZ chain for new special cases

    CERN Document Server

    Murgan, R; Murgan, Rajan; Nepomechie, Rafael I.

    2005-01-01

    The transfer matrix of the general integrable open XXZ quantum spin chain obeys certain functional relations at roots of unity. By exploiting these functional relations, we determine the Bethe Ansatz solution for the transfer matrix eigenvalues for the special cases that all but one of the boundary parameters are zero, and the bulk anisotropy parameter is i\\pi/3, i\\pi/5 ,...

  9. Concurrent Product & Supply Chain Creation

    DEFF Research Database (Denmark)

    Gubi, Ebbe

    it is a structural premise. We also know that logistics costs generally are estimated 15-20% of total product costs. Accordingly, it stands to reason that a company can reduce costs, and thereby gain an edge on its competitors, by tailoring the supply chain in question to an individual product or product family; i......The purpose of this thesis is to increase the understanding of interplays between products and supply chains. In academia, there seem to be an acknowledgement that the nature of a given product has a major influence on the performance of the supply chain associated with it – for one.......e. by creating Focused Supply Chains. At the same time, customer satisfaction can be increased. As a second means to achieving a better fit between product and supply chain, the firm can deploy Design for Logistics, the discipline of considering the supply chain during product creation. The thesis sets out...

  10. Supply chain collaboration under uncertainty

    OpenAIRE

    Hasan, Saad; Eckert, Claudia; Earl, Chris

    2012-01-01

    In fluctuating economic conditions such as global recession, supply chains operate under changing conditions of uncertainty. The impact of this uncertainty and associated risk might be mitigated by collaboration. This paper proposes a model of supply chain collaboration based on information exchange and decision coordination at both the strategic and tactical levels. However, a collaborative supply chain can be exposed to associated risks such as the failure of individual actors. Governance r...

  11. Chain formation of metal atoms

    DEFF Research Database (Denmark)

    Bahn, Sune Rastad; Jacobsen, Karsten Wedel

    2001-01-01

    The possibility of formation of single-atomic chains by manipulation of nanocontacts is studied for a selection of metals (Ni, Pd, Pt, Cu, Ag, Au). Molecular dynamics simulations show that the tendency for chain formation is strongest for Au and Pt. Density functional theory calculations indicate...... that the metals which form chains exhibit pronounced many-atom interactions with strong bonding in low coordinated systems....

  12. Social Media and Supply Chain

    Directory of Open Access Journals (Sweden)

    Sonja Markova

    2013-02-01

    Full Text Available Web 2.0, also referred to as social media, is the use of the World Wide Web to increase creativity, information sharing, and collaboration among users. Social media is driving the rethinking of many of the principles of economics. The use of social media within supply chains is lagging behind their usage for other operational functions, however supply chain management is evolving into supply chain management 2.0.The purpose of this article is to provide researches of the supply chain management a reference with the main concepts of social media: social profiles, social applications, brand outposts and communities, and the social ecosystem.

  13. Social Media and Supply Chain

    OpenAIRE

    Sonja Markova; Tatjana Petkovska-Mirčevska

    2013-01-01

    Web 2.0, also referred to as social media, is the use of the World Wide Web to increase creativity, information sharing, and collaboration among users. Social media is driving the rethinking of many of the principles of economics. The use of social media within supply chains is lagging behind their usage for other operational functions, however supply chain management is evolving into supply chain management 2.0.The purpose of this article is to provide researches of the supply chain manageme...

  14. Quench Dynamics of Two Coupled Ionic Zig-Zag Chains

    CERN Document Server

    Klumpp, Andrea; Schmelcher, Peter

    2015-01-01

    We explore the nonequilibrium dynamics of two coupled zig-zag chains of trapped ions in a double well potential. Following a quench of the potential barrier between both wells, the induced coupling between both chains due to the long-range interaction of the ions leads to their complete melting. The resulting dynamics is however not exlusively irregular but leads to phases of motion during which quasistationary structures appear with the ions arranged in a plethora of ordered and symmetric configurations. A normal mode analysis shows that distinguished modes lead to the decisive population transfer responsible for this sequence of regular and irregular structures.

  15. Requirements of supply chain management in differentiating European pork chains

    NARCIS (Netherlands)

    Trienekens, J.H.; Wognum, P.M.

    2013-01-01

    This paper summarizes results obtained by research into pork chain management in the EU Integrated Project Q-Porkchains. Changing demands for intrinsic and extrinsic quality attributes of pork products impact the way supply chain management should be organized from the farmer down to the consumer. T

  16. Trends in Technology Transfer.

    Science.gov (United States)

    Starnick, Jurgen

    1988-01-01

    Various forms of technology transfer in Europe and North America are discussed including research contracts, cooperative research centers, and personnel transfer. Examples of approaches to technology transfer are given and the establishment of personnel transfer is discussed. Preconditions for successful technology transfer in the future are…

  17. Synthesis of π-conjugated polymers containing aminoquinoline-borafluorene complexes in the main-chain.

    Science.gov (United States)

    Tokoro, Yuichiro; Nagai, Atsushi; Tanaka, Kazuo; Chujo, Yoshiki

    2012-04-13

    The regulation of electron transfer between a conjugated polymer and ligands orthogonally connected to the main-chain is reported. Poly(arylene-ethynylene)s containing aminoquinoline-borafluorene complexes in the main-chain are synthesized in good yields by a Sonogashira-Hagihara coupling. Single crystal X-ray analysis of a model compound has elucidated the complex's structure in which the aminoquinolate moiety and the borafluorene ring are connected directly and orthogonally. Moreover, the optical properties of the polymers are characterized by UV-vis absorption and photoluminescence spectra. Perfluorinated alkyl chain-containing polymers show strong emission, while hydrocarbon chain-containing ones exhibit only a slight emission. DFT calculation suggests that an electron transfer from the excited main-chain to the aminoquinolate ligand is suppressed because of the lowered LUMO level by introducing the electron withdrawing groups, resulting in the significant emission.

  18. Food chain and radioactivity

    International Nuclear Information System (INIS)

    Laboratory experiments on the transfer factors of 129I from environment to rice plant were carried out in the following two systems : (1) atmosphere-to-rice plant (deposition) and (2) soil-to-rice plant (root uptake). Mass normalized deposition velocity (Vd) and grain number normalized deposition velocity (Vs) of gaseous inorganic iodine (I2) on unhulled rice were 0.1 cm3g-1s-1 and 0.4 cm3 (100 grain)-1s-1, respectively. The distribution ratios of the deposited iodine between unhulled rice and brown rice, and between brown rice and polished rice were about 100:4 and 100:40, respectively. The deposition velocities of organic iodine, which is in many cases dominant in the atmosphere, were also studied. Both VD and Vs of organic iodine were nearly one percent of those of inorganic one. Distribution pattern of organic iodine between unhulled rice and brown rice was much different from that of inorganic one. The soil-plant transfer factors for polished rice and for brown rice on a dry weight basis at the time of harvest were 0.002 and 0.006, respectively. It was observed that concentration of radioiodine in the soil solution increased with the plant growth, though the soil-water distribution coefficient (Kd) of the soil used in the experiment was very high (more than 1000). This was attributed to the reduced condition in the soil caused by the effects of root and/or micro-organisms. It was observed that iodine was released into the air from rice plant as an organic form. (author)

  19. Delocalization of mechanical waves in the ladder chain of DNA with correlated disorder

    Science.gov (United States)

    Farzadian, O.; Niry, M. D.

    2016-05-01

    Localization-delocalization transition of mechanical vibrations in a ladder chain with correlated disorder is studied analytically and numerically. An exact analytical analysis is carried out for the delocalization properties of the waves in the ladder chain. This analysis predicts resonance frequencies at which the waves can propagate in the entire chain like DNA. Our analytical results in prediction of extended modes are confirmed by numerical simulations using the transfer matrix method. Finally we consider the entropy of disorder as a control parameter for localization-delocalization transition in chain with correlated disorder.

  20. SUPPLY CHAIN STRATEGIES IN THE CONTEXT OF AN E-COMMERCE CHAIN (E-CHAIN

    Directory of Open Access Journals (Sweden)

    João Gilberto Mendes do Reis

    2014-05-01

    Full Text Available This paper purpose to explore the relationships between supply chain strategies and product performance in retail e-commerce. In this case, we concern that in current, in order to bear up under competition, organizations have to manage their supply chains so that they meet the needs of their final customers. With this concept in mind, the research presented in this study focuses on establishing the right strategy for supply chains according to their product segment. Thus, after a Literature Review, the paper explain a methodology based in different authors studies. Finally the article focuses on a pratical case in e-commerce retail that describes its application in this field. The research shows that it is possible to use a methodology for classifying supply chains using chain strategies and product features. The use of the right strategy for supply chains will improve the competitive advantage of businesses. One limitation is that the methodology study focuses on only two e-commerce segment; future studies may go further in refining the proposed framework for other segments. The aim of this research is to offer businesses a model for evaluating supply chains, allowing them to improve the performance of their products and services by using the right strategy for supply chains. The classification proposal of this paper presents an original model for classification of supply chains based on different studies on the theme.

  1. Transfer mechanism of temoporfin between liposomal membranes.

    Science.gov (United States)

    Hefesha, Hossam; Loew, Stephan; Liu, Xiangli; May, Sylvio; Fahr, Alfred

    2011-03-30

    The transfer kinetics of temoporfin, a classic photosensitizer, was analyzed by investigating the influence of total lipid content, temperature, as well as charge, acyl chain length, and saturation of the lipids in donor vesicles using a mini ion exchange column technique. The obtained results are consistent with an apparent first order kinetics in which the transfer proceeds through both liposome collisions and through the aqueous phase. We present a corresponding theoretical model that accounts for the detailed distribution of drug molecules in donor and acceptor liposomes and predicts the transfer rates as a function of drug concentration and number of donor and acceptor liposomes. The experimentally observed transfer rates depended strongly on the temperature and comply with the Arrhenius equation. Thermodynamic calculations indicate the transfer process to be entropically controlled. In terms of the charge of donor liposomes, positively charged liposomes showed transfer rates faster than negatively charged liposomes whereas the maximum amount transferred was almost the same. A more rigid structure of the donor liposomes increases the transfer rate of temoporfin, which is caused by expelling the drug from the membrane interior, as proposed in former work. In summary, our combined theoretical/experimental approach offers a systematic way to study the mechanism of drug release from liposome-based delivery systems.

  2. Academic Education Chain Operation Model

    NARCIS (Netherlands)

    Ruskov, Petko; Ruskov, Andrey

    2007-01-01

    This paper presents an approach for modelling the educational processes as a value added chain. It is an attempt to use a business approach to interpret and compile existing business and educational processes towards reference models and suggest an Academic Education Chain Operation Model. The model

  3. Negotiations in Supply Chain Management

    DEFF Research Database (Denmark)

    Zachariassen, Frederik

    2008-01-01

    negotiation literature. Subsequently, an empirical case study is presented, which explicitly aims at exploring the role of negotiations between members of a supply chain. Based on the findings, the paper concludes on specific, normative guidelines for negotiations for improved supply chain competitiveness...

  4. Realities of Supply Chain Collaboration

    NARCIS (Netherlands)

    Kampstra, R.P.; Ashayeri, J.; Gattorna, J.

    2006-01-01

    Successful supply chain collaboration (SCC) practices are rather exceptional, yet collaboration is believed to be the single most pressing need in supply chain management.In this paper we discuss the realities of SCC, present prerequisites for the collaboration process, indicate where the process st

  5. Mixed Species Ion Chains for Scalable Quantum Computation

    Science.gov (United States)

    Wright, John Albert

    Mixed species chains of barium and ytterbium ions are investigated as a tool for building scalable quantum computation devices. Ytterbium ions provide a stable, environmentally-insensitive qubit that is easily initialized and manipulated, while barium ions are easily entangled with photons that can allow quantum information to be transmitted between systems in modular quantum computation units. Barium and ytterbium are trapped together in a linear chain in a linear rf trap and their normal mode structure and the thermal occupation numbers of these modes are measured with a narrow band laser addressing an electric quadrupole transition in barium ions. Before these measurements, barium ions are directly cooled using Doppler cooling, while the ytterbium ions are sympathetically cooled by the barium. For radial modes strongly coupled to ytterbium ions the average thermal occupation numbers vary between 400 and 12,000 depending on ion species configuration and trap parameters. Ion chain temperatures are also measured using a technique based on ion species reordering. Surface traps with many dc electrodes provide the ability to controllably reorder the chain to optimize normal mode cooling, and initial work towards realizing this capability are discussed. Quantum information can be transferred between ions in a linear chain using an optical system that is well coupled to the motional degrees of freedom of the chain. For this reason, a 532 nm Raman system is developed and its expected performance is evaluated.

  6. Managing the Global Supply Chain

    DEFF Research Database (Denmark)

    Hsuan, Juliana; Skjøtt-Larsen, Tage; Kinra, Aseem;

    The world today faces global competition. The supply chain is vital part of the globalization process. Presenting a global view of the scope and complexity of supply chain management, this book reflects the rapid change that has taken place within the supply chain and its environment. This new...... edition has been fully updated with recent changes in concepts, technology and practice. Integration and collaboration are keywords in future competition. Firms must be agile and lean at the same time. The book gives an insightful overview of the conceptual foundations of the global supply chain, as...... well as current examples of best practice of managing supply chains in a global context....

  7. Developing sustainable food supply chains.

    Science.gov (United States)

    Smith, B Gail

    2008-02-27

    This paper reviews the opportunities available for food businesses to encourage consumers to eat healthier and more nutritious diets, to invest in more sustainable manufacturing and distribution systems and to develop procurement systems based on more sustainable forms of agriculture. The important factors in developing more sustainable supply chains are identified as the type of supply chain involved and the individual business attitude to extending responsibility for product quality into social and environmental performance within their own supply chains. Interpersonal trust and working to standards are both important to build more sustainable local and many conserved food supply chains, but inadequate to transform mainstream agriculture and raw material supplies to the manufactured and commodity food markets. Cooperation among food manufacturers, retailers, NGOs, governmental and farmers' organizations is vital in order to raise standards for some supply chains and to enable farmers to adopt more sustainable agricultural practices. PMID:17766237

  8. Environmental Management in Product Chains

    DEFF Research Database (Denmark)

    Jørgensen, Michael Søgaard; Forman, Marianne

    2009-01-01

    ). An overview of examples from our own research and from literature of the type and the role of environmental issues and initiatives in product chains (fourth section). A typology for characterizing corporate strategies as part of environmental management in product chains and characterizing those competencies......The chapter aims at giving background to companies, consultants, governmental regulators, NGOs etc. for the analysis and planning of environmental management in specific product chains through: A framework for understanding environmental management in product chains as shaped by the interaction...... between existing resources, norms and values and external pressures for environmental management (second section). A model for the types of corporate network relations that need to be mapped and understood in order to analyze and/or develop environmental management in a product chain (third section...

  9. Managing the Global Supply Chain

    DEFF Research Database (Denmark)

    Skjøtt-Larsen, Tage; Schary, Philip B.; Mikkola, Juliana Hsuan;

    The world today faces global competition. The supply chain is vital part of the globalization process. Presenting a global view of the scope and complexity of supply chain management, this book reflects the rapid change that has taken place within the supply chain and its environment. This new...... well as current examples of best practice of managing supply chains in a global context....... edition has been fully updated with recent changes in concepts, technology and practice. Integration and collaboration are keywords in future competition. Firms must be agile and lean at the same time. The book gives an insightful overview of the conceptual foundations of the global supply chain, as...

  10. Transfers of entanglement qudit states in quantum networks

    CERN Document Server

    Sawerwain, Marek

    2013-01-01

    The issue of quantum states' transfer -- in particular, for so-called Perfect State Transfer (PST) -- in the networks represented by the spin chains seems to be one of the major concerns in quantum computing. Especially, in the context of future communication methods that can be used in broadly defined computer science. The chapter presents a definition of Hamiltonian describing the dynamics of quantum data transfer in one-dimensional spin chain, which is able to transfer the state of unknown qudits. The main part of the chapter is the discussion about possibility of entangled states' perfect transfer, in particular, for the generalized Bell states for qudits. One of the sections also contains the results of numerical experiments for the transmission of quantum entangled state in a noisy quantum channel.

  11. From Characters to Quantum (Super)Spin Chains via Fusion

    CERN Document Server

    Kazakov, Vladimir

    2008-01-01

    We give an elementary proof of the Bazhanov-Reshetikhin determinant formula for rational transfer matrices of the twisted quantum super-spin chains associated with the gl(K|M) algebra. This formula describes the most general fusion of transfer matrices in symmetric representations into arbitrary finite dimensional representations of the algebra and is at the heart of analytical Bethe ansatz approach. Our technique represents a systematic generalization of the usual Jacobi-Trudi formula for characters to its quantum analogue using certain group derivatives.

  12. A lattice gas model on a tangled chain

    International Nuclear Information System (INIS)

    We have used a model of a lattice gas defined on a tangled chain to study the enzyme kinetics by a modified transfer matrix method. By using a simple iterative algorithm we have obtained different kinds of saturation curves for different configurations of the tangled chain and different types of the additional interactions. In some special cases of configurations and interactions we have found the same equations for the saturation curves, which we have obtained before studying the lattice gas model with nearest neighbor interactions or the lattice gas model with alternate nearest neighbor interactions, using different techniques as the correlated walks' theory, the partition point technique or the transfer matrix model. This more general model and the new results could be useful for the experimental investigations. (author). 20 refs, 6 figs

  13. Supply Chain Coordination and Consumer Awareness for Pollution Reduction

    Directory of Open Access Journals (Sweden)

    Bowon Kim

    2016-04-01

    Full Text Available To understand the dynamics of the manufacturer’s effort to reduce pollution in a supply chain consisting of manufacturer, retailer, and consumers, we analyze four cases according to consumer awareness of the pollution’s harmful effect, i.e., environmentally aware versus ignorant, and supply chain coordination, i.e., competitive versus cooperative. Applying differential games, we derive managerial implications: the most significant is that the supply chain coordination strategy becomes irrelevant to reducing the pollution, if the consumers are not environmentally aware or sensitive enough. It highlights the critical role played by the consumer awareness in curbing the pollution in the supply chain. In addition, we find the transfer price and the potential market size are important factors to determine each case’s relative effectiveness. Under a regular condition, where the transfer price from the retailer to the manufacturer is sufficiently high, the consumer-aware and competitive case can generate a better outcome in reducing the pollution than those with ignorant consumers. However, the opposite might occur if the transfer price is excessively low, giving the manufacturer little motivation to make an effort to reduce the pollution. For the cooperative supply chain, it is the potential market size that determines whether the consumer-aware case is better than the consumer-ignorant. In fact, it turns out that there is a stronger result, i.e., the feasibility condition enforces that the market is always big enough to make the consumer-aware cooperative case better than the consumer-ignorant cases. We further discuss managerial as well as policy implications of these analysis outcomes.

  14. Research on the Logistics Supply Chain in Port Logistics Transportation

    Directory of Open Access Journals (Sweden)

    Wang Yan-liang

    2013-11-01

    Full Text Available The aim of this study is to improve and increase the logistics system effectiveness and to solve the problem of optimal movement of different flows. Logistics transport carrying the world on material resources transfer exchange important mission and economic development and our lives are closely linked, logistics chain logistics transport occupies an important position and in the e logistics chain in port logistics has play a decisive role. For many coastal countries port logistics is the economic lifeline of the country, on China's economic development role as important, port logistics transport bear the material exchange with the external communication of important role, so the Chinese port logistics transportation research, clear port logistics transportation, current situation, find the existing problems in the light of the problem, to find a suitable method for solving has great realistic meaning. To promote logistics development, improve the logistics supply chain system has play an important role in this filed.

  15. Overview of coordination contracts within forward and reverse supply chains

    DEFF Research Database (Denmark)

    Govindan, Kannan; Popiuc, M.N.; Diabat, A.

    2013-01-01

    Contracts are comprehensive coordination mechanisms used in both theory and practice to coordinate various supply chain structures. By focusing on the coordination by contracts of the forward and reverse supply chains, the intention of this paper is to (1) present an overview of contracting...... literature and (2) suggest a classification of coordination contracts and contracting literature in the form of classification schemes. The criteria used for contract classification are transfer payment contractual incentives and inventory risk sharing. The classification schemes are based on the level...... of detail used in designing the coordination models. The paper gives a complete overview of the literature that addresses coordination by contracts, structures and classifies the existing work, and draws a parallel between the research conducted on the forward supply chain and the research on the reverse...

  16. Chains, clusters, inclusion compounds, paramagnetic labels, and organic rings

    CERN Document Server

    Zanello, P

    1994-01-01

    The role of stereochemistry to elucidate reaction patterns and physico-chemical properties in topical subjects ranging from inorganic to organic chemistry are treated in the fifth and final volume of this series. Detailed accounts are given to study: chaining in polyphosphates, electron-transfers in carbonyl clusters, inclusion of organometallic molecules in cyclodextrins, stereochemistry of paramagnetic metal complexes by labeling with nitroxyl radicals, stereocontrol in organic syntheses assisted by inorganic complexes.

  17. Generalized T-Q relations and the open XXZ chain

    CERN Document Server

    Murgan, R; Murgan, Rajan; Nepomechie, Rafael I.

    2005-01-01

    We propose a generalization of the Baxter T-Q relation which involves more than one independent Q(u). We argue that the eigenvalues of the transfer matrix of the open XXZ quantum spin chain are given by such generalized T-Q relations, for the case that at most two of the boundary parameters {\\alpha_-, \\alpha_+, \\beta_-, \\beta_+} are nonzero, and the bulk anisotropy parameter has values \\eta = i \\pi/2, i\\pi/4, ...

  18. Elastic Behavior of Polymer Chains

    Institute of Scientific and Technical Information of China (English)

    Teng Lu; Tao Chen; Hao-jun Liang

    2008-01-01

    The elastic behavior of the polymer chain was investigated in a three-dimensional off-lattice model. We sample more than 109 conformations of each kind of polymer chain by using a Monte Carlo algorithm, then analyze them with the non-Gaussian theory of rubberlike elasticity, and end with a statistical study. Through observing the effect of the chain flexibility and the stretching ratio on the mean-square end-to-end distance,the average energy, the average Helmholtz free energy, the elastic force, the contribution of energy to the elastic force, and the entropy contribution to elastic force of the polymer chain, we find that a rigid polymer chain is much easier to stretch than a flexible polymer chain. Also, a rigid polymer chain will become difficult to stretch only at a quite high stretching ratio because of the effect of the entropy contribution.These results of our simulation calculation may explain some of the macroscopic phenomena of polymer and biomacromolecular elasticity.

  19. Improving supply chain collaborations and performance of inefficient supply chain

    Directory of Open Access Journals (Sweden)

    M. Sanei

    2010-03-01

    Full Text Available Modern manufacturing enterprises are required to collaborate by their business partners through their business process operations such as design, manufacture, distribution, and aftersales services. And furthermore performance evaluation is of great importance for effective supply chain man agement. Therefore, DEA can help companies to remove some of the in efficiencies in operational processes in order to become more effective. The current paper develops one approach for determining the DEA projections for inefficient supply chains. Meanwhile this approach aims at providing an easy, efficient and more practical approach based on the performance evaluation for the multi-member supply chain. And ultimately, this model is illustrated by an numerical example of Chinese commercial bank, and case study application to provide of machine-making supply chain.

  20. Review of the ecological parameters of radionuclide turnover in vertebrate food chains

    International Nuclear Information System (INIS)

    Ecological studies of radionuclides in the environment have a long tradition in developing the capability to identify and predict movement and concentration of nuclides in agricultural food chains leading to man. Food chain pathways and transfer coefficients for the nonagricultural portions of natural and managed ecosystems characteristic of affected habitats adjacent to nuclear facilities have not been adequately characterized to establish reliable models for radionuclide releases. This information is necessary in order to assess the impact that such installations will have on the biota of natural ecosystems. Since food chains are the major processes transferring elements from one trophic level to another in terrestrial ecosystems, information is needed on the (a) food-chain transfer pathways, (b) bioconcentration by each trophic component and (c) turnover rates by receptor organisms. These data are prerequisite inputs for food-chain transport models and can be correlated with species characteristics (e.g., body weight and feeding habits), to provide indices for predictive calculations. Application of these models for radionuclide transfer can aid in the assessment of radioactive releases from nuclear reactor facilities to terrestrial nonagricultural food chains

  1. New C sub(21) Delta sup(20) pregnanes, inhibitors of mitochondrial respiratory chain,from Indopacific octocoral Carijoa sp.

    Digital Repository Service at National Institute of Oceanography (India)

    Ciavatta, M.L.; Gresa, M.P.L.; Manzo, E.; Gavagnin, M.; Wahidullah, S.; Cimino, G.

    showed a strong activity in the pre- liminary biological assay for the inhibition of the inte- grated electron transfer chain (NADH oxidase activity) in beef heart submitochondrial particles (SMP). 13 Inhibitory concentration 50% (IC 50 ) for com- pound 1...

  2. New sensors and processing chain

    CERN Document Server

    Yaakoubi, Nourdin

    2014-01-01

    A vital tool for researchers, engineers, and students, New Sensors and Processing Chain focuses on the processing chain to set up in order to extract relevant information on various systems. Highlighting the design of new microsensors and various applications, the authors present recent progress in instrumentation and microsystem design, providing insight to the modification of the sensor itself as well as its environment. Various applications illustrate the presentations, which show how a processing chain is organized from the data acquired by a specific sensor.

  3. Markov chains theory and applications

    CERN Document Server

    Sericola, Bruno

    2013-01-01

    Markov chains are a fundamental class of stochastic processes. They are widely used to solve problems in a large number of domains such as operational research, computer science, communication networks and manufacturing systems. The success of Markov chains is mainly due to their simplicity of use, the large number of available theoretical results and the quality of algorithms developed for the numerical evaluation of many metrics of interest.The author presents the theory of both discrete-time and continuous-time homogeneous Markov chains. He carefully examines the explosion phenomenon, the

  4. Chains of Mean Field Models

    OpenAIRE

    Hassani, S. Hamed; Macris, Nicolas; Urbanke, Ruediger

    2011-01-01

    We consider a collection of Curie-Weiss (CW) spin systems, possibly with a random field, each of which is placed along the positions of a one-dimensional chain. The CW systems are coupled together by a Kac-type interaction in the longitudinal direction of the chain and by an infinite range interaction in the direction transverse to the chain. Our motivations for studying this model come from recent findings in the theory of error correcting codes based on spatially coupled graphs. We find tha...

  5. Transfer Entropy as a Log-Likelihood Ratio

    Science.gov (United States)

    Barnett, Lionel; Bossomaier, Terry

    2012-09-01

    Transfer entropy, an information-theoretic measure of time-directed information transfer between joint processes, has steadily gained popularity in the analysis of complex stochastic dynamics in diverse fields, including the neurosciences, ecology, climatology, and econometrics. We show that for a broad class of predictive models, the log-likelihood ratio test statistic for the null hypothesis of zero transfer entropy is a consistent estimator for the transfer entropy itself. For finite Markov chains, furthermore, no explicit model is required. In the general case, an asymptotic χ2 distribution is established for the transfer entropy estimator. The result generalizes the equivalence in the Gaussian case of transfer entropy and Granger causality, a statistical notion of causal influence based on prediction via vector autoregression, and establishes a fundamental connection between directed information transfer and causality in the Wiener-Granger sense.

  6. Knowledge Transfer Services

    Directory of Open Access Journals (Sweden)

    Albert Simard

    2009-03-01

    include independence from content, an organizational focus, scalability, two drivers, and two levels of resolution. The model is based on a value chain in which value is embedded, advanced, or extracted. A knowledge services system comprises nine stages: generate, transform, manage, use internally, transfer, add value, use professionally, use personally, and evaluate. Knowledge services are delivered through a delivery spectrum ranging from rich to reach. Each region of the delivery spectrum has a set of attributes that influence how services should be delivered.

  7. Quantum state transfer by time reversal in the continuum

    Science.gov (United States)

    Longhi, S.

    2016-03-01

    A method for high-fidelity quantum state transfer in a quantum network coupled to a continuum, based on time reversal in the continuum after decay, is theoretically suggested. Provided that the energy spectrum of the network is symmetric around a reference energy and symmetric energy states are coupled the same way to the common continuum, ideal perfect state transfer can be obtained after time reversal. In particular, it is shown that in a linear tight-binding chain a quantum state can be transformed into its mirror image with respect to the center of the chain after a controllable time. As compared to a quantum mirror image based on coherent transport in a static chain with properly tailored inhomogeneous hopping rates, our method does not require hopping rate engineering and is less sensitive to disorder for long transfer times.

  8. Cryogenic heat transfer

    CERN Document Server

    Barron, Randall F

    2016-01-01

    Cryogenic Heat Transfer, Second Edition continues to address specific heat transfer problems that occur in the cryogenic temperature range where there are distinct differences from conventional heat transfer problems. This updated version examines the use of computer-aided design in cryogenic engineering and emphasizes commonly used computer programs to address modern cryogenic heat transfer problems. It introduces additional topics in cryogenic heat transfer that include latent heat expressions; lumped-capacity transient heat transfer; thermal stresses; Laplace transform solutions; oscillating flow heat transfer, and computer-aided heat exchanger design. It also includes new examples and homework problems throughout the book, and provides ample references for further study.

  9. Supply Chain Shipment Pricing Data

    Data.gov (United States)

    US Agency for International Development — This data set provides supply chain health commodity shipment and pricing data. Specifically, the data set identifies Antiretroviral (ARV) and HIV lab shipments to...

  10. Gravity Waves from Chain Inflation

    CERN Document Server

    Ashoorioon, Amjad

    2008-01-01

    Chain inflation proceeds through a series of first order phase transitions, which can release considerable gravitational waves (GW). We demonstrate that bubble collisions can leave an observable signature for future high-frequency probes of GWs, such as advanced LIGO, LISA and BBO. A "smoking gun" for chain inflation would be wiggles in the spectrum (and consequently in the tensor spectral index) due to the multiple phase transitions. The spectrum could also be distinguished from a single first order phase transition by a small difference in the amplitude at low frequency. A second origin of GWs in chain inflation are tensor modes from quantum fluctuations; these GW can dominate and be observed on large scales. The consistency relation between scalar and tensor modes is different for chain inflation than for standard rolling models and is testable by Cosmic Microwave Background experiments. If inflation happened through a series of rapid tunnelings in the string landscape, future high frequency probes of GW c...

  11. Ownership Structure in Agrifood Chains

    NARCIS (Netherlands)

    G.W.J. Hendrikse (George); W.J.J. Bijman (Jos)

    2000-01-01

    textabstractThis article analyses the impact of ownership structure on investments in a three-party supply chain from an incomplete contracting perspective. Circumstances are determined in which a marketing cooperative is the unique first-best ownership structure.

  12. Risikobasiertes Supply-Chain-Management

    DEFF Research Database (Denmark)

    Wieland, Andreas; Schinz, Philipp

    2015-01-01

    Das Management erlebt seit einigen Jahren dahingehend einen Paradigmenwechsel, dass nicht mehr Unternehmen als einzelne autonome Einheiten im Wettbewerb zueinander stehen, sondern die Supply Chains, in denen diese Unternehmen eingebunden sind. Ursachen hierfür sind beispielsweise die Auslagerung ...

  13. Supply Chain Management and Hypercompetition

    OpenAIRE

    Kotzab, H,; Grant, DB; Teller, C.; Halldorsson, A

    2008-01-01

    Firms nowadays face significant challenges in their operating environments, which have been characterised in two different ways. From a strategic management perspective these environments are in a state of hypercompetition while from a logistics or supply chain perspective these environments require market responsiveness predicated upon agile supply chains. However, firms must also rely on many interorganizational relationships to ensure efficient and effective movements within their supply c...

  14. Product Classification in Supply Chain

    OpenAIRE

    Xing, Lihong; Xu, Yaoxuan

    2010-01-01

    Oriflame is a famous international direct sale cosmetics company with complicated supply chain operation but it lacks of a product classification system. It is vital to design a product classification method in order to support Oriflame global supply planning and improve the supply chain performance. This article is aim to investigate and design the multi-criteria of product classification, propose the classification model, suggest application areas of product classification results and intro...

  15. The chain re-action

    CERN Multimedia

    2009-01-01

    On 18 March, beam commissioning started in the first ‘link’ of the accelerator chain – LINAC 2. This marks the start of what will be the longest period of beam operations in CERN’s history, with the accelerator complex remaining operational throughout the winter to supply the LHC. The Bulletin finds out what is being done to make sure the whole chain is ready for this historic run.

  16. Environmental management in product chains

    DEFF Research Database (Denmark)

    Jørgensen, Michael Søgaard; Forman, Marianne; Hansen, Anne Grethe

    of environmental initiatives, a number of recommendations for governmental regulation, which can support the further diffusion of environmental management in product chains, are developed. Furthermore, the report describes a number of theoretical perspectives from sociology of technology, organisation theory......, network theory, innovation theory, competence development and political science, which are proposed as focus in future capacity development as part of governmental strategies, which aim at supporting emergence and stabilisation of environmental concerns as part of product chain dynamics....

  17. Developing sustainable food supply chains

    OpenAIRE

    Smith, B. Gail

    2007-01-01

    This paper reviews the opportunities available for food businesses to encourage consumers to eat healthier and more nutritious diets, to invest in more sustainable manufacturing and distribution systems and to develop procurement systems based on more sustainable forms of agriculture. The important factors in developing more sustainable supply chains are identified as the type of supply chain involved and the individual business attitude to extending responsibility for product quality into so...

  18. Thermal radiation heat transfer

    CERN Document Server

    Howell, John R; Siegel, Robert

    2016-01-01

    Further expanding on the changes made to the fifth edition, Thermal Radiation Heat Transfer, 6th Edition continues to highlight the relevance of thermal radiative transfer and focus on concepts that develop the radiative transfer equation (RTE). The book explains the fundamentals of radiative transfer, introduces the energy and radiative transfer equations, covers a variety of approaches used to gauge radiative heat exchange between different surfaces and structures, and provides solution techniques for solving the RTE.

  19. Effect of chain wheel shape on crank torque, freely chosen pedal rate, and physiological responses during submaximal cycling

    DEFF Research Database (Denmark)

    Hansen, Ernst Albin; Jensen, Kurt; Hallén, Jostein;

    2009-01-01

    at preset pedal rates. During cycling at the freely chosen pedal rate (being 93+/-6 and 93+/-4 rpm for the Biopace and circular chain wheel, respectively), blood lactate concentration was significantly different between the two chain wheels, being on average 0.2 mmol l(-1) lower with the Biopace chain wheel...... revolution, the observed slightly lower muscle activity may result from larger transfer of energy from the legs to the crank....

  20. Sports Nutrition Food Industry Chain Development Research

    OpenAIRE

    Jie Yin

    2015-01-01

    Through the study of Henan sports nutrition food industry chain optimization, the study analyses development advantage and competitive advantage of Henan in sports nutrition food industry chain and existing problems and challenges in Henan sports nutrition food industry chain and at the same time introduces the theory of supply chain management to the development of sports nutrition food industry chain, clearly optimizes countermeasures of sports nutrition food industry chain. Pointing out sp...

  1. Risk Management in Biopharmaceutical Supply Chains

    OpenAIRE

    Ma, Yao

    2011-01-01

    Biopharmaceutical supply chains present considerable complexity issue for the formulation of optimal plans due to significant uncertainty in the supply chain. The primary goal of biopharmaceutical supply chain planning is to provide reliable supply to patients while coping with various supply chain risks. In chapter 1 first I discuss the key elements and basic characteristics of the biopharmaceutical supply chain . Then I present the major challenges in biopharmaceutical supply chain planning...

  2. ANALYSIS OF IMPACT RESISTANCE OF CHAIN ACCORDING TO SPROCKET LUG PROFILE

    Directory of Open Access Journals (Sweden)

    Berezhnoy S. B.

    2015-03-01

    Full Text Available The possibility of using involute sprockets, more technologically advanced in manufacturing, compared with sprockets with straight, convex-concave profile of the lug on the criterion shock resistance circuit, the maximum permissible speed of the drive sprocket for bush roller chain drives and gears with a toothed chain. The comparative analysis of researches of operation of roller and tooth chain gearings with various steps and types of profiles of sprockets showed that in all cases with increase in a step of a chain the coefficient of speed of blow increases, and the increase in number of lugs at sprockets reduces the speed of blow of the hinge about sprockets tooth. Value of coefficient of speed of blow for couple an evolvent sprockets - a gear chain is much less than value of coefficient of speed of blow for couple a plug-roller chain –sprockets of any profile. Less noise during the work of tooth chain gearings is due to evolvent sprockets. As a result of researches it is established that on kinetic energy of impact of sprockets and the hinge of a chain, sprockets with an evolvent profile can be applied on an equal basis with the sprockets having concave-convex or rectilinear profiles of lugs. Respectively, evolvent sprockets can be used both in chain transfers with roller and with gear chains

  3. Game analysis of the knowledge sharing mechanism for the supply chain collaborative innovation

    Directory of Open Access Journals (Sweden)

    Liang Liu

    2015-01-01

    Full Text Available Purpose: In information economy era, innovation is the key to improve the competitiveness of enterprises. The traditional way of enterprise innovation is outdated and supply chain collaborative innovation has becoming popular. This paper aims to analyses the mechanism of knowledge sharing between enterprises in supply chain collaborative innovation. Design/methodology/approach: This paper analyzes the supply chain members’ willingness to share knowledge by using the game theory. And the result of knowledge sharing between two companies is analyzed by using the evolutionary game. Findings: We broke the knowledge sharing process in supply chain collaborative innovation into knowledge mining and knowledge transferring. We got the best knowledge sharing strategy of each supply chain member. We gave the influencing factors of knowledge sharing between members for the knowledge sharing mechanisms in supply chain collaborative innovation. Research limitations/implications: We didn’t study the willingness of more than two supply chain members to share knowledge and the result of knowledge sharing between them. And this situation is more realistic. Practical implications: Our findings can help to improve the effect of knowledge sharing in supply chain collaborative innovation. Originality/value: The paper introduces the game theory to knowledge sharing between members in supply chain collaborative innovation, deepens the understanding of knowledge sharing in supply chain collaborative innovation, and gives some interesting findings.

  4. Demand chain management - The evolution

    Directory of Open Access Journals (Sweden)

    D Ericsson

    2011-06-01

    Full Text Available The concepts of Supply Chain Management (SCM and Demand Chain Management (DCM are among the new and debated topics concerning logistics in the literature. The question considered in this paper is: “Are these concepts needed or will they just add to the confusion?” Lasting business concepts have always evolved in close interaction between business and academia. Different approaches start out in business and they are then, more or less si- multaneously, aligned, integrated, systemised and structured in academia. In this way a terminology (or language is provided that helps in further diffusion of the concepts. There is a lack of consensus on the definition of the concept of SCM. This may be one of the major reasons for the difficulty in advancing the science and measuring the results of implementation in business. Relationships in SCM span from rather loose coalitions to highly structured virtual network integrations. DCM is a highly organised chain in which the key is mutual interdependence and partnership. The purpose is to create a distinctive competence for the chain as a whole that helps to identify and satisfy customer needs and wishes. The classical research concerning vertical marketing systems is very helpful in systemising the rather unstructured discussions in current SCM research. The trend lies in increasing competition between channels rather than between companies, which in turn leads to the creation of channels with a high degree of partnership and mutual interdependence between members. These types of channels are known as organised vertical marketing systems in the classic marketing channel research. The behaviour in these types of channels, as well as the formal and informal structures, roles in the network, power and dependence relations, etc. are well covered topics in the literature. The concept of vertical marketing systems lies behind the definition of demand chains and demand chain management proposed in this paper. A

  5. Linear chains and chain-like fractals from electrostatic heteroaggregation.

    Science.gov (United States)

    Kim, Anthony Y; Hauch, Kip D; Berg, John C; Martin, James E; Anderson, Robert A

    2003-04-01

    The internal structure of materials prepared by aggregation of oppositely charged polystyrene spheres (electrostatic heteroaggregation) is investigated by static light scattering, optical microscopy, and Brownian dynamics simulation. Light scattering indicates ultralow mass fractal dimensions, as low as 1.2. Such low fractal dimensions, approaching the theoretical limit of a linear object, imply a chaining mechanism. Optical micrographs reveal linear chains with the particle charge alternating down the chains. Brownian dynamics simulation gives additional support for a chaining mechanism. For the polystyrene system (120-nm primary particle diameters), the fractal dimension is found to increase from 1.2 to 1.7 as the background electrolyte is increased. In terms of electrostatic screening, the results match those reported recently for larger polystyrene spheres. The low fractal dimensions appear to represent a crossover from linear chains to a structure of diffusion-limited aggregates; however, experiments under density-neutral conditions imply that sedimentation plays an important role in the formation of ultralow fractal dimensions. The practical implication is that microcomposites with a locally uniform distribution of starting materials and almost any degree of branching can be prepared from oppositely charged particles. PMID:12742045

  6. Supply Chain Management Practices in Toy Supply Chains

    DEFF Research Database (Denmark)

    Wong, Chee Yew; Arlbjørn, Jan Stentoft; Johansen, John

    2005-01-01

    Purpose - Innovative products usually experience highly unpredictable and variable demand. This is especially valid for the volatile and seasonal toy industry, which produces high obsolete inventory, lost sales and markdown. In such a volatile industry, what supply chain management (SCM) practices...... (traditional mass-production or push-models). These low-responsive practices in the toy supply chain are not caused only by slow knowledge diffusion. SCM know-how is not yet capable of managing such levels of volatility and seasonality. Therefore, explanations of these theoretical gaps and what new theories...... are applicable and effective? This study seeks to explore SCM practices, and identify practical and theoretical gaps in toy supply chains. Design/methodology/approach - This article includes a longitudinal and in-depth case study during the past year in an international toy manufacturer, which includes...

  7. OPEN KINEMATIC CHAIN EXERCISES FOR SICK SCAPULA IN COMPETITIVE ASYMPTOMATIC OVER HEAD ATHLETES FOR 3 WEEKS

    OpenAIRE

    Patel Neelam Jayesh; Anil R. Muragod; Basavaraj Motimath

    2014-01-01

    Background and Objective: SICK scapula may result in ineffective energy transfer, placing added stress on the tissues around the shoulder which must compensate for a weak link in the chain. This added stress may result in further muscle fatigue and tissue injury about the shoulder. Restoring and maintaining a stable scapular base is essential to rehabilitating the shoulder and returning to the sport. So the present study intends to study the effectiveness of open kinematic chain exercises ...

  8. Exact solution for the spin-$s$ XXZ quantum chain with non-diagonal twists

    OpenAIRE

    Yung, C. M.; Batchelor, M.T.

    1995-01-01

    We study integrable vertex models and quantum spin chains with toroidal boundary conditions. An interesting class of such boundaries is associated with non-diagonal twist matrices. For such models there are no trivial reference states upon which a Bethe ansatz calculation can be constructed, in contrast to the well-known case of periodic boundary conditions. In this paper we show how the transfer matrix eigenvalue expression for the spin-$s$ XXZ chain twisted by the charge-conjugation matrix ...

  9. Competitive behaviour in supply chains

    Directory of Open Access Journals (Sweden)

    Sylwia Konecka

    2014-06-01

    Full Text Available Background: The article deals with the results of literature and empirical research into competitiveness and behaviour of entities in supply chains. Methods: A research hypothesis has been formulated that both partnership as well as dominance relations occur between enterprises functioning as suppliers-consignees. In order to verify the hypothesis a survey was completed in 2012. It encompassed 116 enterprises (manufacturers - 33, service providers - 32 and sellers - 24 as well as enterprises selling goods and providing services - 27 of which 54 were large, 26 medium and 36 were small enterprises. Competitive behaviour in supply chains has been identified and analysed. Furthermore, the authors intended to identify, reveal and examine possible interdependences between competitive behaviour and behaviour typical of supply chain strategies. Results and conclusions: The analysis of survey results revealed a tendency to preserve equilibrium between a chain leader and dependent enterprises. It may be easily justified in practice as on the one hand there is a need to keep the supply chain competitive and on the other hand to avoid the interruptions, which could occur as a result of elimination of dependent enterprises.

  10. Chains of Mean Field Models

    CERN Document Server

    Hassani, S Hamed; Urbanke, Ruediger

    2011-01-01

    We consider a collection of mean field spin systems, each of which is placed on the positions of a one-dimensional chain, coupled together by a Kac-type interaction along the chain. We analyze the simplest possible cases where the individual system is a Curie-Weiss model, possibly with a random field. We are interested in the regime where the size of each mean field model tends to infinity and, the length of the chain and range of the Kac interaction are large but finite. Below the critical temperature, there appears a series of equilibrium states representing kink-like interfaces between the two equilibrium states of the individual system. The van der Waals curve oscillates periodically around the Maxwell plateau. These oscillations have a period inversely proportional to the chain length and an amplitude exponentially small in the range of the interaction; in other words the spinodal points of the chain model lie exponentially close to the phase transition threshold. The amplitude of the oscillations is clo...

  11. Ultrafast Charge Transfer Visualized by Two-Dimensional Electronic Spectroscopy

    OpenAIRE

    Mančal T.; Milota F.; Hauer J; Christensson N.; Bixner O.; Lukeš V.; Kauffmann H. F.

    2013-01-01

    Two-dimensional electronic spectroscopy (2D-ES) is used to investigate ultrafast excited-state dynamics in a lutetium bisphthalocyanine dimer. Following optical excitation, a chain of electron and hole transfer steps gives rise to characteristic cross-peak dynamics in the electronic 2D spectra. The combination of density matrix propagation and quantum chemical calculations results in a molecular view of the charge transfer dynamics and highlights the role of the counter-ion in providing an en...

  12. Towards biotracing in food chains

    DEFF Research Database (Denmark)

    Hoorfar, Jeffrey; Wagner, Martin; Jordan, Kieran;

    2011-01-01

    Biotracing is tracing (backward)/tracking (forward) biological contamination in the food/feed chain. Advances in detection technologies, improvements in molecular marker identification, clearer understanding of pathogenicity markers, improved modelling methodologies and, more importantly, the int......Biotracing is tracing (backward)/tracking (forward) biological contamination in the food/feed chain. Advances in detection technologies, improvements in molecular marker identification, clearer understanding of pathogenicity markers, improved modelling methodologies and, more importantly......, and 21 cross-disciplinary work packages that cover tracing and tracking of contamination in feed, meat and dairy chains, in addition to accidental and deliberate contamination of bottled water. The BIOTRACER Consortium consists of 46 partners, including Europe's largest food/feed industries, several SMEs...

  13. Ligand chain length conveys thermochromism.

    Science.gov (United States)

    Ganguly, Mainak; Panigrahi, Sudipa; Chandrakumar, K R S; Sasmal, Anup Kumar; Pal, Anjali; Pal, Tarasankar

    2014-08-14

    Thermochromic properties of a series of non-ionic copper compounds have been reported. Herein, we demonstrate that Cu(II) ion with straight-chain primary amine (A) and alpha-linolenic (fatty acid, AL) co-jointly exhibit thermochromic properties. In the current case, we determined that thermochromism becomes ligand chain length-dependent and at least one of the ligands (A or AL) must be long chain. Thermochromism is attributed to a balanced competition between the fatty acids and amines for the copper(II) centre. The structure-property relationship of the non-ionic copper compounds Cu(AL)2(A)2 has been substantiated by various physical measurements along with detailed theoretical studies based on time-dependent density functional theory. It is presumed from our results that the compound would be a useful material for temperature-sensor applications. PMID:24943491

  14. MODELING SUPPLY CHAIN PERFORMANCE VARIABLES

    Directory of Open Access Journals (Sweden)

    Ashish Agarwal

    2005-01-01

    Full Text Available In order to understand the dynamic behavior of the variables that can play a major role in the performance improvement in a supply chain, a System Dynamics-based model is proposed. The model provides an effective framework for analyzing different variables affecting supply chain performance. Among different variables, a causal relationship among different variables has been identified. Variables emanating from performance measures such as gaps in customer satisfaction, cost minimization, lead-time reduction, service level improvement and quality improvement have been identified as goal-seeking loops. The proposed System Dynamics-based model analyzes the affect of dynamic behavior of variables for a period of 10 years on performance of case supply chain in auto business.

  15. Designing the Reverse Supply Chain

    DEFF Research Database (Denmark)

    Gobbi, Chiara

    2011-01-01

    for the reverse supply chain. Design/methodology/approach – In order to identify the relevance of the Fisher model, the model needs to be recast in terms of PRV, which, in this context, is considered the independent variable in the reverse logistics arena. Products defined as innovative in Fisher's taxonomy......Purpose – The purpose of this paper is to explore the impact of the product residual value (PRV) and the loss of value over time of returned products in the reverse supply chain configuration. It also examines whether or not the distinction of Fisher's functional and innovative products holds...... correspond to disposed products with high residual value, whereas functional products correspond to disposed products with low residual value. Furthermore, the PRV and the speed at which returned products lose their value are considered in order to determine the configuration of the reverse supply chain...

  16. Convective heat transfer

    CERN Document Server

    Kakac, Sadik; Pramuanjaroenkij, Anchasa

    2014-01-01

    Intended for readers who have taken a basic heat transfer course and have a basic knowledge of thermodynamics, heat transfer, fluid mechanics, and differential equations, Convective Heat Transfer, Third Edition provides an overview of phenomenological convective heat transfer. This book combines applications of engineering with the basic concepts of convection. It offers a clear and balanced presentation of essential topics using both traditional and numerical methods. The text addresses emerging science and technology matters, and highlights biomedical applications and energy technologies. What’s New in the Third Edition: Includes updated chapters and two new chapters on heat transfer in microchannels and heat transfer with nanofluids Expands problem sets and introduces new correlations and solved examples Provides more coverage of numerical/computer methods The third edition details the new research areas of heat transfer in microchannels and the enhancement of convective heat transfer with nanofluids....

  17. Introduction to heat transfer

    CERN Document Server

    SUNDÉN, B

    2012-01-01

    Presenting the basic mechanisms for transfer of heat, Introduction to Heat Transfer gives a deeper and more comprehensive view than existing titles on the subject. Derivation and presentation of analytical and empirical methods are provided for calculation of heat transfer rates and temperature fields as well as pressure drop. The book covers thermal conduction, forced and natural laminar and turbulent convective heat transfer, thermal radiation including participating media, condensation, evaporation and heat exchangers.

  18. Markov chains and mixing times

    CERN Document Server

    Levin, David A; Wilmer, Elizabeth L

    2009-01-01

    This book is an introduction to the modern approach to the theory of Markov chains. The main goal of this approach is to determine the rate of convergence of a Markov chain to the stationary distribution as a function of the size and geometry of the state space. The authors develop the key tools for estimating convergence times, including coupling, strong stationary times, and spectral methods. Whenever possible, probabilistic methods are emphasized. The book includes many examples and provides brief introductions to some central models of statistical mechanics. Also provided are accounts of r

  19. Thermodynamics of Dipolar Chain Systems

    DEFF Research Database (Denmark)

    R. Armstrong, J.; Zinner, Nikolaj Thomas; V. Fedorov, D.;

    2012-01-01

    The thermodynamics of a quantum system of layers containing perpendicularly oriented dipolar molecules is studied within an oscillator approximation for both bosonic and fermionic species. The system is assumed to be built from chains with one molecule in each layer. We consider the effects...... numerically. Our findings indicate that thermodynamic observables, such as the heat capacity, can be used to probe the signatures of the intralayer interaction between chains. This should be relevant for near future experiments on polar molecules with strong dipole moments....

  20. MANAGING RISK IN SUPPLY CHAIN

    OpenAIRE

    Karppinen, Sami

    2015-01-01

    In this master thesis the focus was to study risk management in supply chain management. During the work different types of risks were studied and how they affect purchasing in industry. The purpose of the work was also to enhance the writer’s ability to do his own daily work and to bring new views to his employer for managing a supply chain. In this work different techniques which have been introduced in the industry were reviewed. During the work, an interview survey was made among the ...

  1. Reseach of Supply Chain Modeling Technology

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The supply chain modeling technology is research. Firstly, the concept of supply chain and supply chain management is introduced. Secondly, enterprise-modeling methods, such as CIM-OSA, GIM-GRAI, PERA and ARIS, are analyzed and compared. The supply chain modeling technology is studied. Then the ARIS-based supply chain modeling method is proposed and the supply chain operation reference model is set up. Finally, the applications of ARIS-based supply chain modeling method in Shanghai Turbine Generator Co. Ltd. (STGC) is described in detail.

  2. Transfer of gaming

    NARCIS (Netherlands)

    Korteling, J.E.

    2012-01-01

    An overview is provided of the activities and results op GATE WP 4.4 entiteld Transfer of Gaming (ToG). This work package has produced the principles and methodologies concerning optimalization and measurement of transfer of training in serious gaming. In addition, true transfer of job-specific comp

  3. Electrical communication between glucose oxidase and different ferrocenylalkanethiol chain lengths

    Energy Technology Data Exchange (ETDEWEB)

    Rubin, S.; Bar, G.; Cutts, R.W.; Zawodzinski, T.A. Jr. [Los Alamos National Lab., NM (United States); Chow, J.T.; Ferraris, J.P. [Univ. of Texas, Richardson, TX (United States). Dept. of Chemistry

    1995-12-31

    We describe the factors affecting the electron transfer process between the different components of a self-assembled mixed monolayer. The system is comprised of mixed monolayers containing aminoalkanethiols (AMATs) and ferrocenylakanethiols (FATs) of variable chain lengths. We study the effects of different ratio of the two mixed monolayer components on the permeability of the monolayer toward a Ru(NH{sub 3}{sub 6}Cl{sub 3} redox probe. In order to study the electrical communication between the enzyme and the mediator molecules, the enzyme glucose oxidase (GOx) was attached to the AMAT sites to create a biosensor device. The relative efficiency of a biosensor of each chain-length combination of FAT and AMAT was examined. In light of this comparison, we consider the critical factors for efficient electron transfer between the ferrocene mediator and the GOx redox active site immobilized as part of the surface-confined system. We find that the biosensor response is greatest when the enzyme and the FATs are attached to the surface with different alkane chain lengths. We also find strong evidence for the existence of domains of FAT and AMAT in the mixed monolayer system.

  4. Extended State to Localization in Random Aperiodic Chains

    Science.gov (United States)

    Gao, Hui-Fen; Tao, Rui-Bao

    2006-11-01

    The electronic states in Thus-Morse chain (TMC) and generalized Fibonacci chain (GFC) are studied by solving eigenequation and using transfer matrix method. Two model Hamiltonians are studied. One contains the nearest neighbor (n.n.) hopping terms only and the other has additionally next nearest neighbor (n.n.n.) hopping terms. Based on the transfer matrix method, a criterion of transition from the extended to the localized states is suggested for GFC and TMC. The numerical calculation shows the existence of both extended and localized states in pure aperiodic system. A random potential is introduced to the diagonal term of the Hamiltonian and then the extended states are always changed to be localized. The exponents related to the localization length as a function of randomness are calculated. For different kinds of aperiodic chain, the critical value of randomness for the transition from extended to the localized states are found to be zero, consistent with the case of ordinary one-dimensional systems.

  5. Extended State to Localization in Random Aperiodic Chains

    Institute of Scientific and Technical Information of China (English)

    GAO Hui-Fen; TAO Rui-Bao

    2006-01-01

    The electronic states in Thus-Morse chain (TMC) and generalized Fibonacci chain (GFC) are studied by solving eigenequation and using transfer matrix method. Two model Hamiltonians are studied. One contains the nearest neighbor (n.n.) hopping terms only and the other has additionally next nearest neighbor (n.n.n.) hopping terms. Based on the transfer matrix method, a criterion of transition from the extended to the localized states is suggested for GFC and TMC. The numerical calculation shows the existence of both extended and localized states in pure aperiodic system. A random potential is introduced to the diagonal term of the Hamiltonian and then the extended states are always changed to be localized. The exponents related to the localization length as a function of randomness are calculated. For different kinds of aperiodic chain, the critical value of randomness for the transition from extended to the localized states are found to be zero, consistent with the case of ordinary one-dimensional systems.

  6. Deterministic assembly of linear gold nanorod chains as a platform for nanoscale applications

    DEFF Research Database (Denmark)

    Rey, Antje; Billardon, Guillaume; Loertscher, Emanuel;

    2013-01-01

    We demonstrate a method to assemble gold nanorods highly deterministically into a chain formation by means of directed capillary assembly. This way we achieved straight chains consisting of end-to-end aligned gold nanorods assembled in one specific direction with well-controlled gaps of similar...... to 6 nm between the individual constituents. We determined the conditions for optimum quality and yield of nanorod chain assembly by investigating the influence of template dimensions and assembly temperature. In addition, we transferred the gold nanorod chains from the assembly template onto a Si/SiO2...... target substrate, thus establishing a platform for a variety of nanoscale electronic and optical applications ranging from molecular electronics to optical and plasmonic devices. As a first example, electrical measurements are performed on contacted gold nanorod chains before and after their immersion...

  7. Singular eigenstates in the even(odd) length Heisenberg spin chain

    CERN Document Server

    Giri, Pulak Ranjan

    2014-01-01

    Introducing a regularization scheme, we derive a set of equations for the rapidities of the singular solutions, whose distinct and self-conjugate solutions produce Bethe eigenstates. We obtain singular eigenstates and their corresponding eigenvalues of the transfer matrix of the spin-1/2 XXX chain. For an even length spin-1/2 XXX chain, we show that the singular solutions \\{\\lambda_\\alpha\\} are invariant under the sign changes of their rapidities, \\{\\lambda_\\alpha\\}=\\{-\\lambda_\\alpha\\}. For odd N length spin-1/2 chain in the three down-spin sector, it has been analytically shown that there exist singular solutions in any finite length of the spin chain of the form N= 3\\left(2k+1\\right) with k=1, 2, 3, \\cdots. It is also shown that there exist no singular solutions in the four down-spin sector for some odd length spin-1/2 XXX chains.

  8. Sustainability Analysis for Gayo Coffee Supply Chain

    OpenAIRE

    Rachman Jaya; Machfud Machfud; Sapta Raharja; Marimin Marimin

    2013-01-01

    Sustainable supply chain is a development of the conventional supply chains that discuses trade-off among economic, social and environmental dimensions in order to achieve better responsiveness in terms of quality, quantity and time-delivery in the supply chain structure. The objective of this research was to determine the Gayo coffee supply chain sustainability. The research was conducted at Bener Meriah and Aceh Tengah Districts, Aceh Province, Indonesia. Key actors in the supply chain cons...

  9. Supply Chains and Social Network Analysis

    OpenAIRE

    Mueller, Rolf A.E.; Buergelt, Doreen; Seidel-Lass, Linda

    2008-01-01

    Judged by its currency, the supply chain is one of the more successful metaphors in economics. The metaphor borrows from mechanics the idea of the chain, that is something that consists of elements that are linked to each of their two immediate neighbors and which jointly provide a strong but flexible connection. The metaphor transplants the chain-idea into the sphere of economics where, before the introduction of supply chains, chains were, for most economists, things best left in the care o...

  10. SUPPLY CHAIN MANAGEMENT – KEY FACTORS

    OpenAIRE

    Magdalena Daniela DINU

    2014-01-01

    This paper exposes Supply Chain Management by its key factors. Briefly, where the Supply Chain Management is treated as strategic part of a company then maintaining both control and influence throughout the entire supply chain are key factors and critical to success. On the other hand, finding the right partner to manage the non-strategic Supply Chains would be another key factor too. To define the most important key factors within Supply Chain Management means a deeply understanding of bot...

  11. Research on Integrated Green Supply Chain Management

    Institute of Scientific and Technical Information of China (English)

    DENG Lei; WANG Xu

    2006-01-01

    On the basis of the analyzing product life cycle and value chain management in green supply chain, integrated green supply chain is put forward and constructed which involve lean production, agile manufacturing and green supply chain. This integrated structure provides an effective method for resolving some questions such as cost, market, environment, etc. in enterprise. A case study is presented at the end of paper to demonstrate how integrated supply chain implemented successfully in enterprise.

  12. OVERVIEW OF CHINESE CHAIN CATERING MARKET

    OpenAIRE

    Wang, Yiting

    2012-01-01

    This thesis is a market overview for chain catering business situation in China. Chinese chain catering market is developing rapidly in recent years, it is a business where everybody can become a customer, but the business is highly competitive. The subject of this thesis is to give an overview of the market situation and strategies for market expansion of Chinese chain catering industry. It contains knowledge of chain management and introduction of Chinese chain catering ma...

  13. Precise low cost chain gears for heliostats

    Science.gov (United States)

    Liedke, Phillip; Lewandowski, Arkadiusz; Pfahl, Andreas; Hölle, Erwin

    2016-05-01

    This work investigates the potential of chain gears as precise and low cost driving systems for rim drive heliostats. After explaining chain gear basics the polygon effect and chain lengthening are investigated. The polygon effect could be measured by a heliostat with chain rim gear and the chain lengthening with an accordant test set up. Two gear stages are scope of this work: a rim gear and an intermediate gear. Dimensioning, pretensioning and designing for both stages are explained.

  14. Supply chain management and optimization in manufacturing

    CERN Document Server

    Pirim, Harun; Yilbas, Bekir Sami

    2014-01-01

    This book introduces general supply chain terminology particularly for novice readers, state of the art supply chain management and optimization issues and problems in manufacturing. The book provides insights for making supply chain decisions, planning and scheduling through supply chain network. It introduces optimization problems, i.e. transportation of raw materials, products and location, inventory of plants, warehouses and retailers, faced throughout the supply chain network.

  15. Ontological Supply Chain Management: Concepts, Applications, Extensions

    OpenAIRE

    Ilter, H. Kemal

    2013-01-01

    SCOM: Multi-Layer Ontological Model for Supply Chain Systems© aims to create a model for tracking and tracing products, agents, flows and operations of a supply chain with an upper ontology.  It will hopefully let us to track or trace most properties in not-usual supply chains such as interstellar supply chains (eg. raw materials from the planet Mars), health-related supply chains (eg. blood products), food management (eg. genetic structures of agricultural products), envir...

  16. Electron transfer reactions

    CERN Document Server

    Cannon, R D

    2013-01-01

    Electron Transfer Reactions deals with the mechanisms of electron transfer reactions between metal ions in solution, as well as the electron exchange between atoms or molecules in either the gaseous or solid state. The book is divided into three parts. Part 1 covers the electron transfer between atoms and molecules in the gas state. Part 2 tackles the reaction paths of oxidation states and binuclear intermediates, as well as the mechanisms of electron transfer. Part 3 discusses the theories and models of the electron transfer process; theories and experiments involving bridged electron transfe

  17. Polystyrene chains orientation: A rubbed and non-rubbed polymer comparative study

    Science.gov (United States)

    Ghorbal, Achraf; Arfi, Rim Ben; Bistac, Sophie; Brogly, Maurice

    2007-08-01

    Polarization-modulation infrared reflection-absorption spectroscopy (PMIRRAS) measurements have been carried out so as to analyze atactic polystyrene layers transferred (nano-wear) onto hydroxylated silicon substrates. This technique has been used to determine the three-dimensional orientation geometry of aliphatic part and phenyl rings of rubbed polystyrene on hydroxyl-terminated wafers. The PMIRRAS analysis of PS bulk and transfer film showed an orientation of chains under different mechanical stresses.

  18. The Service-Profit Chain

    DEFF Research Database (Denmark)

    Grønholdt, Lars; Martensen, Anne

    to demonstrate such links, and several issues must be addressed to uncover the links. To investigate these links empirically, a hotel chain provided data matching employee and customer measures with measures of profitability. We have successfully employed a modeling approach, and the paper reports empirical...

  19. Smallest Nanoelectronics with Adatom Chains

    Science.gov (United States)

    Yamada, Toshishige; Saini, Subhash (Technical Monitor)

    1998-01-01

    This viewgraph presentation is focused on the general aspect of atomic chain electronics that I have been studying. Results have been published before, but are being rederived here using a new physical/mathematical picture/model, which deepens the physical understanding. Precise adatom structures can be used as a template on a regulated surface with no uncertainty.

  20. Synchronizing the Retail Supply Chain

    NARCIS (Netherlands)

    P. van der Vlist

    2007-01-01

    textabstractDit proefschrift ontwerpt een retail supply chain, die beter en goedkoper is dan de gangbare. Dit wordt bereikt door de distributie te synchroniseren op de productie¬momenten. Goederen zouden direct uit productie al stroomafwaarts moeten bewegen, van fabrikant naar retailer, tegen lage k

  1. Supply Chain Simulation : A Survey

    NARCIS (Netherlands)

    Kleijnen, J.P.C.

    2003-01-01

    This paper provides a survey of simulation in supply chain management.It reviews four types of simulation, namely spreadsheet simulation, system dynamics, discreteevent simulation, and business games.Which simulation type should be applied, depends on the type of managerial question to be answered b

  2. Preisdifferenzierung im Supply Chain Management

    OpenAIRE

    Koppers, Laura

    2010-01-01

    In the field of marketing, pricing is a valuable and long-established steering tool. But in the logistics context of co-operative strategies like supply chain management, this field is mainly neglected. Therefore, the author describes the basic principles and effects of price differentiation and suggests some further research regarding pricing in SCM considerations as well as co-operative pricing concepts.

  3. Supply Chain Management: een overzicht

    NARCIS (Netherlands)

    Schuring, R.W.

    2012-01-01

    De laatste jaren wordt voor het managen van het netwerk van bedrijven die betrokken zijn bij het tot stand komen van producten of diensten het woord Supply Chain Management, ook wel SCM, gebruikt. SCM wordt als term vooral in grote industrieën gebruikt. Bijna ieder bedrijf heeft echter een toelevern

  4. Transfer function combinations

    KAUST Repository

    Zhou, Liang

    2012-10-01

    Direct volume rendering has been an active area of research for over two decades. Transfer function design remains a difficult task since current methods, such as traditional 1D and 2D transfer functions, are not always effective for all data sets. Various 1D or 2D transfer function spaces have been proposed to improve classification exploiting different aspects, such as using the gradient magnitude for boundary location and statistical, occlusion, or size metrics. In this paper, we present a novel transfer function method which can provide more specificity for data classification by combining different transfer function spaces. In this work, a 2D transfer function can be combined with 1D transfer functions which improve the classification. Specifically, we use the traditional 2D scalar/gradient magnitude, 2D statistical, and 2D occlusion spectrum transfer functions and combine these with occlusion and/or size-based transfer functions to provide better specificity. We demonstrate the usefulness of the new method by comparing to the following previous techniques: 2D gradient magnitude, 2D occlusion spectrum, 2D statistical transfer functions and 2D size based transfer functions. © 2012 Elsevier Ltd.

  5. Integrity and efficiency in LNG transfer operations with flexible hoses

    NARCIS (Netherlands)

    Bokhorst, E. van; Twerda, A.

    2014-01-01

    The work presented contributes to the LNG supply chain by the development of a validated calculation model for corrugated flexible hoses or pipes developed for LNG Transfer. The model builds upon experience gained by TNO Technical Sciences (Fluid Dynamics) in a large number of flow tests carried out

  6. Fertilizer supply chain in Ethiopia: structure, performance and policy analysis

    Directory of Open Access Journals (Sweden)

    Johanes U.I. Agbahey

    2015-07-01

    Full Text Available In Ethiopia, less than 40% of farmers use fertilizer and those who do, apply rates significantly below those recommended. This low fertilizer use is primarily due to prices being two to three times higher than prices on the world markets. Reducing the price of fertilizer requires a sound understanding of the product´s supply chain. This study investigates whether fertilizer is delivered to farmers in an efficient way and at the lowest possible costs using an institutional economics framework. It was conducted in the Arsi zone and relied on secondary data as well as primary data collected through interviews. The findings point out the presence of several formal and informal institutions regulating the market. A market monopoly at each stage of the supply chain and a striking correspondence between the central organization of the chain and the rise in left-over stocks were observed. This pinpoints the imperfect structure of the chain and a misallocation of resources locked up in fertilizer stockholding. In order to improve the demand estimation procedure, this study suggests that incentives should be instituted to enhance the reliability of the information transferred along the process. Additionally, expert knowledge used in the process should be well documented, stock inventories should not be limited to central warehouses and stockholding needs to be reduced.

  7. Dimension conversion and scaling of disordered protein chains.

    Science.gov (United States)

    Li, Maodong; Sun, Tanlin; Jin, Fan; Yu, Daqi; Liu, Zhirong

    2016-08-16

    To extract protein dimension and energetics information from single-molecule fluorescence resonance energy transfer spectroscopy (smFRET) data, it is essential to establish the relationship between the distributions of the radius of gyration (Rg) and the end-to-end (donor-to-acceptor) distance (Ree). Here, we performed a coarse-grained molecular dynamics simulation to obtain a conformational ensemble of denatured proteins and intrinsically disordered proteins. For any disordered chain with fixed length, there is an excellent linear correlation between the average values of Rg and Ree under various solvent conditions, but the relationship deviates from the prediction of a Gaussian chain. A modified conversion formula was proposed to analyze smFRET data. The formula reduces the discrepancy between the results obtained from FRET and small-angle X-ray scattering (SAXS). The scaling law in a coil-globule transition process was examined where a significant finite-size effect was revealed, i.e., the scaling exponent may exceed the theoretical critical boundary [1/3, 3/5] and the prefactor changes notably during the transition. The Sanchez chain model was also tested and it was shown that the mean-field approximation works well for expanded chains. PMID:27440558

  8. Ultrafast Charge Transfer Visualized by Two-Dimensional Electronic Spectroscopy

    Directory of Open Access Journals (Sweden)

    Mančal T.

    2013-03-01

    Full Text Available Two-dimensional electronic spectroscopy (2D-ES is used to investigate ultrafast excited-state dynamics in a lutetium bisphthalocyanine dimer. Following optical excitation, a chain of electron and hole transfer steps gives rise to characteristic cross-peak dynamics in the electronic 2D spectra. The combination of density matrix propagation and quantum chemical calculations results in a molecular view of the charge transfer dynamics and highlights the role of the counter-ion in providing an energetic perturbation which promotes charge transfer across the complex.

  9. Molecularly Imprinted Polymers on Chloromethyl Polystyrene Resin Prepared via RAFT Polymerization

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Surface molecularly imprinted polymers (SMIP) was prepared via the reversible addition-fragmentation chain transfer (RAFT) polymerization on the chloromethyl polystyrene resin (CPR) in the presence of the template D-phenylalanine. The structure of SMIP was characterized by FTIR and SEM. The adsorption behavior of D-phenylalanine of SMIP was preliminarily investigated.

  10. Molecularly imprinted polymer beads for nicotine recognition prepared by RAFT precipitation polymerization: a step forward towards multifunctionalities

    DEFF Research Database (Denmark)

    Zhou, Tongchang; Jørgensen, Lars; Mattebjerg, Maria Ahlm;

    2014-01-01

    A nicotine imprinted polymer was synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization using methacrylic acid (MAA) as a functional monomer. The resulting molecularly imprinted polymers were monodispersed beads with an average diameter of 1.55 mm. The molecular sel...

  11. Photothermally responsive gold nanoparticle conjugated polymer-grafted porous hollow silica nanocapsules.

    Science.gov (United States)

    Paramelle, David; Gorelik, Sergey; Liu, Ye; Kumar, Jatin

    2016-08-01

    Polymer-grafted porous hollow silica nanoparticles prepared by reversible addition-fragmentation chain transfer polymerisation have an upper critical solution temperature of 45 °C. Conjugation of 5 nm gold nanoparticles onto polymer-grafted porous hollow silica nanoparticles enables remarkable specific photothermally-induced controlled release of encapsulated Rhodamine B by laser-stimulation at physiological temperature. PMID:27427407

  12. Improving supply chain collaborations and performance of inefficient supply chain

    OpenAIRE

    M. Sanei; S. Mamizadeh-Chatghayeh

    2010-01-01

    Modern manufacturing enterprises are required to collaborate by their business partners through their business process operations such as design, manufacture, distribution, and aftersales services. And furthermore performance evaluation is of great importance for effective supply chain man agement. Therefore, DEA can help companies to remove some of the in efficiencies in operational processes in order to become more effective. The current paper develops one approach for determining the DEA p...

  13. Supply Chain Management Performance in Tourism. Continental Hotels Chain Case

    OpenAIRE

    Gabriela Ţigu; Bogdan Călăreţu

    2013-01-01

    With its origins in logistics, Supply Chain Management (SCM) concept is covering all managerial aspects of the flow of materials and information from source to customer, across the entire range of materials handling and movement functions, and throughout an organization and its supply channels. In tourism, these issues relate to the whole process of providing tourism services from sourcing of raw materials, products or different services) to supply and distribution, and SCM performance can ul...

  14. Characterization of the respiratory chain of Helicobacter pylori

    DEFF Research Database (Denmark)

    Chen, M; Andersen, L P; Zhai, L;

    1999-01-01

    The respiratory chain of Helicobacter pylori has been investigated. The total insensitivity of activities of NADH dehydrogenase to rotenone and of NADH-cytochrome c reductase to antimycin is indicative of the absence of the classical complex I of the electron transfer chain in this bacterium. NADPH......-dependent respiration was significantly stronger than NADH-dependent respiration, indicating that this is a major respiratory electron donor in H. pylori. Fumarate and malonate exhibited a concentration-dependent inhibitory effect on the activity of succinate dehydrogenase. The activity of succinate-cytochrome c...... reductase was inhibited by antimycin, implying the presence of a classical pathway from complex II to complex III in this bacterium. The presence of NADH-fumarate reductase (FRD) was demonstrated in H. pylori and fumarate could reduce H2O2 production from NADH, indicating fumarate to be an endogenous...

  15. Quench dynamics of two coupled zig-zag ion chains

    Science.gov (United States)

    Klumpp, Andrea; Liebchen, Benno; Schmelcher, Peter

    2016-08-01

    We explore the non-equilibrium dynamics of two coupled zig-zag chains of trapped ions in a double well potential. Following a quench of the potential barrier between both wells, the induced coupling between both chains due to the long-range interaction of the ions leads to the complete loss of order in the radial direction. The resulting dynamics is however not exclusively irregular but leads to phases of motion during which various ordered structures appear with ions arranged in arcs, lines and crosses. We quantify the emerging order by introducing a suitable measure and complement our analysis of the ion dynamics using a normal mode analysis showing a decisive population transfer between only a few distinguished modes.

  16. Transferência trófica de mercúrio e selênio na costa norte do Rio de Janeiro Trophic transference of mercury and selenium in the northern coast of Rio de Janeiro

    Directory of Open Access Journals (Sweden)

    Helena A. Kehrig

    2009-01-01

    Full Text Available Trophic transfer of trace elements along marine food chains has been recognized as an important process influencing metal and metalloid bioaccumulation. The trophic transfer of mercury was observed between trophic levels from prey (considering fish with different feeding habits and squid to top predator (dolphin in a Northern coastal food chain of Rio de Janeiro. Selenium showed some evidence of trophic transfer between lower trophic levels. Dolphin presented the highest mercury concentrations whereas the benthic carnivorous fish showed the highest selenium concentrations. Mercury is biomagnified through the food chain while selenium does not present the same behavior.

  17. chains

    Directory of Open Access Journals (Sweden)

    Gabriel Pérez-Salas

    2015-01-01

    Full Text Available Las barreras y aranceles al comercio exterior han disminuido significativamente gracias a los acuerdos multilaterales y los mecanismos de integración entre las naciones. Los costos logísticos representan una proporción significativa del precio final de los artículos, especialmente de los commodities. Por esta razón, minimizar los costos logísticos es un desafío importante para las naciones para fomentar la competitividad del comercio exterior y en particular para aprovechar la renta de los recursos naturales. En este artículo, proponemos un marco de referencia integral para la medición de costos logísticos, enfocado en determinar los extra-costos que resultan por procedimientos ineficientes y la falta de políticas públicas y regulaciones de las entidades públicas. Estos elementos no han sido considerados en la literatura, y este artículo aborda esta brecha. Como caso de estudio, presentamos la aplicación del marco de referencia para estimar los extra-costos en algunas cadenas logísticas de recursos naturales en Bolivia. Se presenta una discusión de los resultados encontrados, así como recomendaciones para trabajo futuro.

  18. Quantum state transfer in optomechanical arrays

    Science.gov (United States)

    de Moraes Neto, G. D.; Andrade, F. M.; Montenegro, V.; Bose, S.

    2016-06-01

    Quantum state transfer between distant nodes is at the heart of quantum processing and quantum networking. Stimulated by this, we propose a scheme where one can achieve quantum state transfer with a high fidelity between sites in a cavity quantum optomechanical network. In our lattice, each individual site is composed of a localized mechanical mode which interacts with a laser-driven cavity mode via radiation pressure, while photons hop between neighboring sites. After diagonalization of the Hamiltonian of each cell, we show that the system can be reduced to an effective Hamiltonian of two decoupled bosonic chains, and therefore we can apply the well-known results in quantum state transfer together with an additional condition on the transfer times. In fact, we show that our transfer protocol works for any arbitrary joint quantum state of a mechanical and an optical mode. Finally, in order to analyze a more realistic scenario we take into account the effects of independent thermal reservoirs for each site. By solving the standard master equation within the Born-Markov approximation, we reassure both the effective model and the feasibility of our protocol.

  19. 76 FR 44761 - Remittance Transfers

    Science.gov (United States)

    2011-07-27

    ... Electronic Fund Transfer Act (EFTA), as an example of money transfer instruments Federal credit unions (FCUs... receiving international and domestic electronic fund transfers'' after the words ``money orders'' from... checks, money orders, and other similar transfer instruments, including international and...

  20. Intercombination Effects in Resonant Energy Transfer

    CERN Document Server

    Vaillant, C L; Jones, M P A

    2015-01-01

    We investigate the effect of intercombination transitions in excitation hopping processes such as those found in F\\"orster resonance energy transfer. Taking strontium Rydberg states as our model system, the breakdown of $LS$-coupling leads to weakly allowed transitions between Rydberg states of different spin quantum number. We show that the long-range interactions between two Rydberg atoms can be affected by these weakly allowed spin transitions, and the effect is greatest when there is a near-degeneracy between the initial state and a state with a different spin quantum number. We also consider a case of four atoms in a spin chain, and show that a spin impurity can resonantly hop along the chain. By engineering the many-body energy levels of the spin-chain, the breakdown of $LS$ coupling due to inter-electronic effects in individual atoms can be mapped onto a spatial separation of the total spin and the total orbital angular momentum along the spin chain.

  1. The chain relation in sofic subshifts

    CERN Document Server

    Kazda, Alexandr

    2009-01-01

    The paper gives a characterisation of the chain relation of a sofic subshift. Every sofic subshift $\\Sigma$ can be described by a labelled graph $G$. Factorising $G$ in a suitable way we obtain the graph $G/_\\approx$ that offers insight into some properties of the original subshift. Using $G/_\\approx$ we describe first the chain relation in $\\Sigma$, then characterise chain-transitive sofic subshifts, chain-mixing sofic subshifts and finally the attractors of the subshift dynamic system. At the end we present (straightforward) algorithms deciding chain-transitivity and chain-mixing properties of a sofic subshift and listing all the attractors of the subshift system.

  2. Den teoretiske udvikling af Supply Chain Strategimodeller

    DEFF Research Database (Denmark)

    Arvad Johansen, Jens

    2011-01-01

    segmentering via postponement-princippet, har givet mærkbare forbedringer. Det beskrives endvidere, hvordan produkternes livscyklus påvirker valget af supply chain design. Begrebet Demand Chain Management( DCM), hvormed strategimodeller bruger klassiske marketingelementer sammen med Supply Chain Management......Denne artikel beskriver med udgangspunkt i artikler og virksomhedseksempler udviklingen inde for supply chain strategimodeller. Ved hjælp af tidligere udviklede koncepter besvares spørgsmålet: “Hvad er den rette supply chain for mine produkter?”. Virksomhedseksempler beskriver, hvordan supply chain...... (SCM), bliver behandlet og der udvikles en DCM-strategimodel....

  3. Wave propagation in random granular chains.

    Science.gov (United States)

    Manjunath, Mohith; Awasthi, Amnaya P; Geubelle, Philippe H

    2012-03-01

    The influence of randomness on wave propagation in one-dimensional chains of spherical granular media is investigated. The interaction between the elastic spheres is modeled using the classical Hertzian contact law. Randomness is introduced in the discrete model using random distributions of particle mass, Young's modulus, or radius. Of particular interest in this study is the quantification of the attenuation in the amplitude of the impulse associated with various levels of randomness: two distinct regimes of decay are observed, characterized by an exponential or a power law, respectively. The responses are normalized to represent a vast array of material parameters and impact conditions. The virial theorem is applied to investigate the transfer from potential to kinetic energy components in the system for different levels of randomness. The level of attenuation in the two decay regimes is compared for the three different sources of randomness and it is found that randomness in radius leads to the maximum rate of decay in the exponential regime of wave propagation. PMID:22587093

  4. Wave propagation in random granular chains.

    Science.gov (United States)

    Manjunath, Mohith; Awasthi, Amnaya P; Geubelle, Philippe H

    2012-03-01

    The influence of randomness on wave propagation in one-dimensional chains of spherical granular media is investigated. The interaction between the elastic spheres is modeled using the classical Hertzian contact law. Randomness is introduced in the discrete model using random distributions of particle mass, Young's modulus, or radius. Of particular interest in this study is the quantification of the attenuation in the amplitude of the impulse associated with various levels of randomness: two distinct regimes of decay are observed, characterized by an exponential or a power law, respectively. The responses are normalized to represent a vast array of material parameters and impact conditions. The virial theorem is applied to investigate the transfer from potential to kinetic energy components in the system for different levels of randomness. The level of attenuation in the two decay regimes is compared for the three different sources of randomness and it is found that randomness in radius leads to the maximum rate of decay in the exponential regime of wave propagation.

  5. 单链抗体-包膜蛋白嵌合型单嗜性逆转录病毒构建及靶向感染肿瘤细胞的研究%Tumor cell-specific gene transfer with retroviral vectors displaying single-chain antibody

    Institute of Scientific and Technical Information of China (English)

    汤宇澄; 李煜; 钱关祥

    2002-01-01

    Objective To specifically deliver the therapeutic gene to cancer cells and construct target retroviral vectors by inserting the single-chain variable antibody fragment into the retroviral envelope.Methods Single-chain antibody expression vector pET -20bScfv was constructed. Binding activity of the genetically engineered single-chain variable antibody fragment was verified by enzyme-linked immunosorbent assay (ELISA) and Western blot. At the same time, by means of polymerase chain reaction (PCR)-directed mutagenesis, the appropriate cloning site EcoT22 Ⅰ/Sal Ⅰ was generated at the N-terminus of receptor-binding SU domain in the MoMLV env polypetide. Then the single-chain antibody gene, encoding a functional antibody, was inserted into the cloning site. The Scfv-env fusion gene fragment was subcloned into CMV expression vector. The Lac-Z retrovirus that co-displayed the Scfv-env chimeric protein and wild-type env protein was produced by transfection of Ψ2 cells with retroviral plasmid and the fusion gene expressing plasmid. To confirm the specificity of the recombinant retrovirus, infection assays and competitive inhibition assays were performed.Results The results of ELISA and Western blot showed that the genetically engineered single-chain variable antibody fragment could bind to the SHG44 cells surface membrane antigen. Virus-binding assay, viral infection and competitive inhibition assays confirmed that the harvested virus efficiently bound to and infected SHG44 cancer cells expressing the relative membrane antigen specially via the recognition of the target antigen.Conclusion These results imply that insertion of Scfv into the retroviral envelope can specifically deliver the interested gene into specific antigen-producing cancer cells.%目的将单链抗体基因插入单嗜性逆转录病毒胞膜蛋白,以构建能靶向感染肿瘤细胞的逆转录病毒载体。方法 构建单链抗体融合表达质粒PET20b-scFv,

  6. Supply Chain Reorganization and Coordination

    Institute of Scientific and Technical Information of China (English)

    WANG Feng-bin

    2001-01-01

    Three generic forms of governance--hierarchy, hybrid and market are proposed in the newinstitutional economics, giving an abstract description of alternative coordination and control mechanisms forgeneral use. While this theory is known as far away from being operational and specified, a few researchersin the management and organization area are trying to extend Galbraith and/or Mintzberg's organizationaldesign theories into the application of logistical coordination for obtaining a smooth flow of products along thesupply chain within and without the focal organization. In this paper, we present an explorative case study onthe design of various organizational architectures of logistics activities and their relevant coordinationmechanisms, especially internal and external contracts as one new kind of hybrid mechanisms forcoordinating effective supply chains.

  7. Waste Transfer Stations

    DEFF Research Database (Denmark)

    Christensen, Thomas Højlund

    2011-01-01

    tion and transport is usually the most costly part of any waste management system; and when waste is transported over a considerable distance or for a long time, transferring the waste from the collection vehicles to more efficient transportation may be economically beneficial. This involves...... a transfer station where the transfer takes place. These stations may also be accessible by private people, offering flexibility to the waste system, including facilities for bulky waste, household hazardous waste and recyclables. Waste transfer may also take place on the collection route from small...... satellite collection vehicles to large compacting vehicles that cannot effectively travel small streets and alleys within the inner city or in residential communities with narrow roads. However, mobile transfer is not dealt with in this chapter, which focuses on stationary transfer stations. This chapter...

  8. Conjugal transfer and characterization of bacteriocin plasmids in group N (lactic acid) streptococci.

    Science.gov (United States)

    Neve, H; Geis, A; Teuber, M

    1984-01-01

    Thirteen bacteriocin-producing strains of group N (lactic acid) streptococci were screened for their potential to transfer this property by conjugation to Streptococcus lactis subsp. diacetylactis Bu2-60. Bacteriocin production in three strains was plasmid encoded as shown by conjugal transfer and by analysis of cured, bacteriocin-negative derivatives of the donor strains and the transconjugants. With Streptococcus cremoris strains 9B4 and 4G6 and S. lactis subsp. diacetylactis 6F7 as donors, bacteriocin-producing transconjugants were isolated with frequencies ranging from ca. 2 X 10(-2) to 2 X 10(-1) per recipient cell. Bacteriocin-producing transconjugants had acquired a 39.6-megadalton plasmid from the donor strains 9B4 and 4G6, and a 75-megadalton plasmid from the donor strain 6F7. As shown by restriction endonuclease analysis, the plasmids from strains 9B4 and 4G6 were almost identical. The plasmid from strain 6F7 yielded some additional fragments not present in the two other plasmids. In hybridization experiments any of the three plasmids strongly hybridized with each other and with some other bacteriocin but nontransmissible plasmids from other S. cremoris strains. Homology was also detected to a variety of cryptic plasmids in lactic acid streptococci. Images PMID:6321437

  9. Automated polymerase chain reaction in capillary tubes with hot air.

    Science.gov (United States)

    Wittwer, C T; Fillmore, G C; Hillyard, D R

    1989-06-12

    We describe a simple, compact, inexpensive thermal cycler that can be used for the polymerase chain reaction. Based on heat transfer with air to samples in sealed capillary tubes, the apparatus resembles a recirculating hair dryer. The temperature is regulated via thermocouple input to a programmable set-point process controller that provides proportional output to a solid state relay controlling a heating coil. For efficient cooling after the denaturation step, the controller activates a solenoid that opens a door to vent hot air and allows cool air to enter. Temperature-time profiles and amplification results approximate those obtained using water baths and microfuge tubes.

  10. Q-operators for the open Heisenberg spin chain

    Directory of Open Access Journals (Sweden)

    Rouven Frassek

    2015-12-01

    Full Text Available We construct Q-operators for the open spin-12 XXX Heisenberg spin chain with diagonal boundary matrices. The Q-operators are defined as traces over an infinite-dimensional auxiliary space involving novel types of reflection operators derived from the boundary Yang–Baxter equation. We argue that the Q-operators defined in this way are polynomials in the spectral parameter and show that they commute with transfer matrix. Finally, we prove that the Q-operators satisfy Baxter's TQ-equation and derive the explicit form of their eigenvalues in terms of the Bethe roots.

  11. Q-operators for the open Heisenberg spin chain

    CERN Document Server

    Frassek, Rouven

    2015-01-01

    We construct Q-operators for the open spin-1/2 XXX Heisenberg spin chain with diagonal boundary matrices. The Q-operators are defined as traces over an infinite-dimensional auxiliary space involving novel types of reflection operators derived from the boundary Yang-Baxter equation. We argue that the Q-operators defined in this way are polynomials in the spectral parameter and show that they commute with transfer matrix. Finally, we prove that the Q-operators satisfy Baxter's TQ-equation.

  12. Q-operators for the open Heisenberg spin chain

    Science.gov (United States)

    Frassek, Rouven; Szécsényi, István M.

    2015-12-01

    We construct Q-operators for the open spin-1/2 XXX Heisenberg spin chain with diagonal boundary matrices. The Q-operators are defined as traces over an infinite-dimensional auxiliary space involving novel types of reflection operators derived from the boundary Yang-Baxter equation. We argue that the Q-operators defined in this way are polynomials in the spectral parameter and show that they commute with transfer matrix. Finally, we prove that the Q-operators satisfy Baxter's TQ-equation and derive the explicit form of their eigenvalues in terms of the Bethe roots.

  13. CHARACTERISTICS OF THE VALUE CHAIN OF THE GLOBAL VALUE CHAIN AND THE SCOPE OF THE CHAIN ANALYSIS

    OpenAIRE

    Luu, Thai

    2013-01-01

    The value chain of vegetable industry is a line of production processing business of vegetable under the mode of globalization, of which, economic subjects of many countries involve in the different stages in the chain. The method of global approach under the value chain has been developed over time and is used as an analysis tool in market research of the global vegetable industry. Three key elements of the pattern of analysis scope of the global vegetable value chain analysis of the global ...

  14. Supply Chain Simulation: A Survey

    OpenAIRE

    Kleijnen, J.P.C.

    2003-01-01

    This paper provides a survey of simulation in supply chain management.It reviews four types of simulation, namely spreadsheet simulation, system dynamics, discreteevent simulation, and business games.Which simulation type should be applied, depends on the type of managerial question to be answered by the model.Moreover, this paper summarizes novel sensitivity and robustness analyses.This sensitivity analysis yields a shortlist of the truly important factors in large simulation models with (sa...

  15. The Milk Supply Chain Project.

    OpenAIRE

    Smith, Howard; Thanassoulis, John

    2008-01-01

    This report presents the results of an Oxford University research project into the UK liquid milk supply chain. Financial sponsorship was kindly provided by the Milk Development Council (MDC) and by DEFRA. The research reported here is independent academic research which is not designed to further any group‟s particular agenda. We have striven to be as objective as possible. The project's aim is to investigate the competitive forces which influence the buyerseller relationsh...

  16. Organizing the Global Value Chain

    OpenAIRE

    Pol Antràs; Davin Chor

    2012-01-01

    We develop a property-rights model of the firm in which production entails a continuum of uniquely sequenced stages. In each stage, a final-good producer contracts with a distinct supplier for the procurement of a customized stage-specific component. Our model yields a sharp characterization for the optimal allocation of ownership rights along the value chain. We show that the incentive to integrate suppliers varies systematically with the relative position (upstream versus downstream) at whi...

  17. Demand and Supply Chain Management

    OpenAIRE

    Jack A.A. van der Veenl:; Robben, Henry S.J.

    1999-01-01

    In dit artikel wordt ingegaan op de recente ontwikkelingen met be-trekking tot de managementactiviteiten gericht op de keten die begint bij het winnen van grondstoffen en via toeleveranciers, fabrikanten en de (detail)handel loopt naar de eindgebruikers. De moderne denkbeelden op dit terrein worden samengevat met de term Demand & Supply Chain Management (DSCM); het management van de keten die onafhankelijke klanten en leveranciers verbindt als ware het een enkele en-titeit met het doel om waa...

  18. Markov Chain Ontology Analysis (MCOA

    Directory of Open Access Journals (Sweden)

    Frost H

    2012-02-01

    Full Text Available Abstract Background Biomedical ontologies have become an increasingly critical lens through which researchers analyze the genomic, clinical and bibliographic data that fuels scientific research. Of particular relevance are methods, such as enrichment analysis, that quantify the importance of ontology classes relative to a collection of domain data. Current analytical techniques, however, remain limited in their ability to handle many important types of structural complexity encountered in real biological systems including class overlaps, continuously valued data, inter-instance relationships, non-hierarchical relationships between classes, semantic distance and sparse data. Results In this paper, we describe a methodology called Markov Chain Ontology Analysis (MCOA and illustrate its use through a MCOA-based enrichment analysis application based on a generative model of gene activation. MCOA models the classes in an ontology, the instances from an associated dataset and all directional inter-class, class-to-instance and inter-instance relationships as a single finite ergodic Markov chain. The adjusted transition probability matrix for this Markov chain enables the calculation of eigenvector values that quantify the importance of each ontology class relative to other classes and the associated data set members. On both controlled Gene Ontology (GO data sets created with Escherichia coli, Drosophila melanogaster and Homo sapiens annotations and real gene expression data extracted from the Gene Expression Omnibus (GEO, the MCOA enrichment analysis approach provides the best performance of comparable state-of-the-art methods. Conclusion A methodology based on Markov chain models and network analytic metrics can help detect the relevant signal within large, highly interdependent and noisy data sets and, for applications such as enrichment analysis, has been shown to generate superior performance on both real and simulated data relative to existing

  19. China's Role in Purchasing Chain

    Institute of Scientific and Technical Information of China (English)

    Eva; Alice

    2007-01-01

    @@ In current world market,"Made-in-China"often means good price and competitive quality.In terms of China's trade pattern,more than half of Chinese exporting products belong to processing trade industry according to the demands and requirements of international orders.On the purchasing chain,China is learning from its international partners.Safety and quality always tops all issues.

  20. Supply Chain Performance Evaluation: Trends and Challenges

    Directory of Open Access Journals (Sweden)

    Ezutah U. Olugu

    2009-01-01

    Full Text Available Problem statement: In today’s manufacturing world, globalization policies and rejuvenation have created a more intensive competition amongst manufacturers. On the other hand, manufacturers have turned to the option of adopting innovative technologies, process re-engineering and strategies such as efficient supply chain management to achieve a sustainable competitive advantage. Effective supply chain performance measurement has been identified as a key issue towards efficient supply chain management. To explore the extent of research in supply chain performance measurement and establish the gap in knowledge in supply chain performance measurement using fuzzy logic operation. Approach: Literatures in the area of supply chain performance measurement had been extensively reviewed. Both traditional and fuzzy logic approaches to supply chain performance measurement were scrutinized. Further scrutiny was carried out to establish potential research areas in the application of fuzzy logic operations in supply chain performance measurement. Results: The supply chain performance measurement using fuzzy logic operation was identified as a new direction in measuring the uncertainty and ambiguity surrounding supply chain performance measurement. Direction for further studies in the application of fuzzy logic operation in supply chain management and its performance measurement were also identified. Conclusion: Result of this study implied that there is still a gap in knowledge in the area of supply chain performance measurement. This new direction of studies involved extending the existing supply chains to incorporate product recovery after the useful life.

  1. HEAT TRANSFER FLUIDS

    OpenAIRE

    Lenert, Andrej; Nam, Youngsuk; Wang, Evelyn N.

    2012-01-01

    The choice of heat transfer fluids has significant effects on the performance, cost, and reliability of solar thermal systems. In this chapter, we evaluate existing heat transfer fluids such as oils and molten salts based on a new figure of merit capturing the combined effects of thermal storage capacity, convective heat transfer characteristics, and hydraulic performance of the fluids. Thermal stability, freezing point, and safety issues are also discussed. Through a comparative analysis, we...

  2. Gas transfer system

    International Nuclear Information System (INIS)

    The state of work on the Vivitron gas transfer system and the system functions are summarized. The system has to: evacuate the Vivitron reservoir; transfer gas from storage tanks to the Vivitron; recirculate gas during operation; transfer gas from the Vivitron to storage tanks; and assure air input. The system is now being installed. Leak alarms are given by SF6 detectors, which set off a system of forced ventilation. Another system continuously monitors the amount of SF6 in the tanks

  3. Memristive Transfer Matrices

    OpenAIRE

    Mouttet, Blaise

    2010-01-01

    An electrical analysis is performed for a memristor crossbar array integrated with operational amplifiers including the effects of parasitic or contact resistances. It is shown that the memristor crossbar array can act as a transfer matrix for a multiple input-multiple output signal processing system. Special cases of the transfer matrix are described related to reconfigurable analog filters, waveform generators, analog computing, and pattern similarity. Keywords: transfer matrix, memristor, ...

  4. Memristive Transfer Matrices

    CERN Document Server

    Mouttet, Blaise

    2010-01-01

    An electrical analysis is performed for a memristor crossbar array integrated with operational amplifiers including the effects of parasitic or contact resistances. It is shown that the memristor crossbar array can act as a transfer matrix for a multiple input-multiple output signal processing system. Special cases of the transfer matrix are described related to reconfigurable analog filters, waveform generators, analog computing, and pattern similarity. Keywords: transfer matrix, memristor, analog electronics, crossbar, operational amplifier, reconfigurable electronics

  5. Biomechanics of Tendon Transfers.

    Science.gov (United States)

    Livermore, Andrew; Tueting, Jonathan L

    2016-08-01

    The transfer of tendons in the upper extremity is a powerful technique to restore function to a partially paralyzed hand. The biomechanical principles of muscle tension and tendon excursion dictate motor function both in the native as well as transferred states. Appropriately tensioning transferred tendons to maximize the function of the associated muscle remains an area of focused research. Newer methods of tendon coaptation have proven similar in strength to the standard Pulvertaft weave, affording more options to the surgeon. PMID:27387073

  6. Making benefit transfers work

    DEFF Research Database (Denmark)

    Bateman, I. J.; Brouwer, R.; Ferrini, S.;

    2011-01-01

    provides guidance on the appropriate specification of transferable value functions arguing that these should be developed from theoretical rather than ad-hoc statistical principles. These principles are tested via a common format valuation study of water quality improvements across five countries. Results...... support our various hypotheses providing a set of principles for future transfer studies. The application also considers new ways of incorporating distance decay, substitution and framing effects within transfers and presents a novel water quality ladder....

  7. Making benefit transfers work

    DEFF Research Database (Denmark)

    Bateman, I.J.; Brouwer, R.; Ferrini, S.;

    provides guidance on the appropriate specification of transferable value functions arguing that these should be developed from theoretical rather than ad-hoc statistical principles. These principles are tested via a common format valuation study of water quality improvements across five countries. Results...... support our various hypotheses providing a set of principles for future transfer studies. The application also considers new ways of incorporating distance decay, substitution and framing effects within transfers and presents a novel water quality ladder....

  8. Resonance Energy Transfer

    OpenAIRE

    Andrews, David; Bradshaw, David; Dinshaw, Rayomond; Scholes, Gregory

    2015-01-01

    Resonance energy transfer, also known as Förster- or fluorescence- resonance energy transfer, or electronic energy transfer, is a photonic process whose relevance in many major areas of science is reflected both by a wide prevalence of the effect and through numerous technical applications. The process, operating through an optical near-field mechanism, effects a transport of electronic excitation between physically distinct atomic or molecular components, based on transition dipole-dipole co...

  9. ARCHITECTURAL CONCEPTS FOR VALUE CHAINS

    Directory of Open Access Journals (Sweden)

    A.C. Janse van Rensburg

    2012-01-01

    Full Text Available

    ENGLISH ABSTRACT:The Porter Value Chain has been widely adopted by the business community as a mechanism to understand and comprehend complexity in business environments, with the ultimate goal of structuring the business to maximize its competitive advantage. Implementing the Value Chain is not easy: a number of organizations can testify to their failure to derive any benefits at all from this concept. To overcome this problem, an approach is presented to assist the organization in creating a Value Chain reference model within the broader context of the organization’s enterprise architecture.

    AFRIKAANSE OPSOMMING: Die “Porter Waardeketting” is ’n algemene aanvaarde praktyk wat deur maatskappye gebruik word om die kompleksiteit van besigheidsomgewings mee te verstaan. Die uiteindelike doel hiervan is om die besigheid se mededings voordele te optimiseer. Om die Waardekettingkonsep te implementeer, is nie ’n maklike taak nie – verskeie organisasies kan getuig van mislukte implementeringspogings. Hierdie artikel beskryf ’n benadering beskryf wat gebruik kan word om die organisasie te help om ’n Waardekettingmodel te skep in die bree konteks van die organisasie se besigheidsargitektuur.

  10. A lipid transfer protein that transfers lipid

    OpenAIRE

    Levine, T. P.

    2007-01-01

    Very few lipid transfer proteins (LTPs) have been caught in the act of transferring lipids in vivo from a donor membrane to an acceptor membrane. Now, two studies (Halter, D., S. Neumann, S. M. van Dijk, J. Wolthoorn, A. M. de Maziere, O.V. Vieira, P. Mattjus, J. Klumperman, G. van Meer, and H. Sprong. 2007. J. Cell Biol. 179: 101 115; D'Angelo, G., E. Polishchuk, G. D. Tullio, M. Santoro, A. D. Campli, A. Godi, G. West, J. Bielawski, C.C. Chuang, A. C. van der Spoel, et al. 2007. Nature. 449...

  11. Discrete kink dynamics in hydrogen-bonded chains: The two-component model

    DEFF Research Database (Denmark)

    Karpan, V.M.; Zolotaryuk, Yaroslav; Christiansen, Peter Leth;

    2004-01-01

    We study discrete topological solitary waves (kinks and antikinks) in two nonlinear diatomic chain models that describe the collective dynamics of proton transfers in one-dimensional hydrogen-bonded networks. The essential ingredients of the models are (i) a realistic (anharmonic) ion-proton inte...

  12. 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....

  13. Mitochondrial respiratory chain complexes as sources and targets of thiol-based redox-regulation

    NARCIS (Netherlands)

    Drose, S.; Brandt, U.; Wittig, I.

    2014-01-01

    The respiratory chain of the inner mitochondrial membrane is a unique assembly of protein complexes that transfers the electrons of reducing equivalents extracted from foodstuff to molecular oxygen to generate a proton-motive force as the primary energy source for cellular ATP-synthesis. Recent evid

  14. Off-diagonal Bethe ansatz solution of the XXX spin-chain with arbitrary boundary conditions

    CERN Document Server

    Cao, Junpeng; Shi, Kangjie; Wang, Yupeng

    2013-01-01

    With the off-diagonal Bethe ansatz method proposed recently by the present authors, we exactly diagonalize the $XXX$ spin chain with arbitrary boundary fields. By constructing a functional relation between the eigenvalues of the transfer matrix and the quantum determinant, the associated $T-Q$ relation and the Bethe ansatz equations are derived.

  15. Off-diagonal Bethe ansatz solution of the XXX spin chain with arbitrary boundary conditions

    Science.gov (United States)

    Cao, Junpeng; Yang, Wen-Li; Shi, Kangjie; Wang, Yupeng

    2013-10-01

    Employing the off-diagonal Bethe ansatz method proposed recently by the present authors, we exactly diagonalize the XXX spin chain with arbitrary boundary fields. By constructing a functional relation between the eigenvalues of the transfer matrix and the quantum determinant, the associated T-Q relation and the Bethe ansatz equations are derived.

  16. Radial Nerve Tendon Transfers.

    Science.gov (United States)

    Cheah, Andre Eu-Jin; Etcheson, Jennifer; Yao, Jeffrey

    2016-08-01

    Radial nerve palsy typically occurs as a result of trauma or iatrogenic injury and leads to the loss of wrist extension, finger extension, thumb extension, and a reduction in grip strength. In the absence of nerve recovery, reconstruction of motor function involves tendon transfer surgery. The most common donor tendons include the pronator teres, wrist flexors, and finger flexors. The type of tendon transfer is classified based on the donor for the extensor digitorum communis. Good outcomes have been reported for most methods of radial nerve tendon transfers as is typical for positional tendon transfers not requiring significant power. PMID:27387076

  17. Basic heat transfer

    CERN Document Server

    Bacon, D H

    2013-01-01

    Basic Heat Transfer aims to help readers use a computer to solve heat transfer problems and to promote greater understanding by changing data values and observing the effects, which are necessary in design and optimization calculations.The book is concerned with applications including insulation and heating in buildings and pipes, temperature distributions in solids for steady state and transient conditions, the determination of surface heat transfer coefficients for convection in various situations, radiation heat transfer in grey body problems, the use of finned surfaces, and simple heat exc

  18. Information flow in the pharmaceutical supply chain.

    Science.gov (United States)

    Yousefi, Nazila; Alibabaei, Ahmad

    2015-01-01

    Managing the supply chain plays an important role in creating competitive advantages for companies. Adequate information flow in supply chain is one of the most important issues in SCM. Therefore, using certain Information Systems can have a significant role in managing and integrating data and information within the supply chain. Pharmaceutical supply chain is more complex than many other supply chains, in the sense that it can affect social and political perspectives. On the other hand, managing the pharmaceutical supply chain is difficult because of its complexity and also government regulations in this field. Although, Iran has progressed a lot in pharmaceutical manufacturing, still there are many unsolved issues in managing the information flow in the pharmaceutical supply chain. In this study, we reviewed the benefits of using different levels of an integrated information system in the supply chain and the possible challenges ahead. PMID:26664401

  19. Transition Probability Estimates for Reversible Markov Chains

    OpenAIRE

    Telcs, Andras

    2000-01-01

    This paper provides transition probability estimates of transient reversible Markov chains. The key condition of the result is the spatial symmetry and polynomial decay of the Green's function of the chain.

  20. Supply chain strategies, issues and models

    CERN Document Server

    Ramanathan, Ramakrishnan

    2014-01-01

    In the 21st century, supply chain operations and relationships among supply chain partners have become highly challenging, necessitating new approaches, e.g., the development of new models. Supply Chain Strategies, Issues and Models discusses supply chain issues and models with examples from actual industrial cases. Expert authors with a wide spectrum of knowledge working in various areas of supply chain management from various geographical locations offer refreshing, novel and insightful ideas and address possible solutions using established theories and models. Supply Chain Strategies, Issues and Models features studies that have used mathematical modeling, statistical analyses and also descriptive qualitative studies. The chapters cover many relevant themes related to supply chains and logistics including supply chain complexity, information sharing, quality (six sigma), electronic Kanbans, inventory models, scheduling, purchasing and contracts. To facilitate easy reading, the chapters that deal with suppl...

  1. SUPPLY CHAIN MANAGEMENT – KEY FACTORS

    Directory of Open Access Journals (Sweden)

    Magdalena Daniela DINU

    2014-06-01

    Full Text Available This paper exposes Supply Chain Management by its key factors. Briefly, where the Supply Chain Management is treated as strategic part of a company then maintaining both control and influence throughout the entire supply chain are key factors and critical to success. On the other hand, finding the right partner to manage the non-strategic Supply Chains would be another key factor too. To define the most important key factors within Supply Chain Management means a deeply understanding of both Supply Chain’ s components, procedures, workflow, processes and the importance of Supply Chain Management into maximizing company's value. SCORE model able to provide solid information about measuring performance and identifying priorities within Supply Chain Management will help us to understand the key factors by analyzing its elements: Plan, Source, Make, Deliver,Return, Enable. These elements covers all the challenging areas from first to third tier of Supply Chain Management.

  2. Cationic amphiphiles with fatty acyl chain asymmetry of coconut oil deliver genes selectively to mouse lung.

    Science.gov (United States)

    Chandrashekhar, Voshavar; Srujan, Marepally; Prabhakar, Rairala; Reddy, Rakesh C; Sreedhar, Bojja; Rentam, Kiran K R; Kanjilal, Sanjit; Chaudhuri, Arabinda

    2011-03-16

    Recent structure-activity studies have revealed a dramatic influence of hydrophobic chain asymmetry in enhancing gene delivery efficacies of synthetic cationic amphiphiles (Nantz, M. H. et al. Mol. Pharmaceutics2010, 7, 786-794; Koynova, R. et al. Mol. Pharmaceutics2009, 6, 951-958). The present findings demonstrate for the first time that such a transfection enhancing influence of asymmetric hydrocarbon chains observed in pure synthetic cationic amphiphiles also works for cationic amphiphiles designed with natural, asymmetric fatty acyl chains of a food-grade oil. Herein, we demonstrate that cationic amphiphiles designed with the natural fatty acyl chain asymmetry of food-grade coconut oil are less cytotoxic and deliver genes selectively to mouse lung. Despite lauroyl chains being the major fatty acyl chains of coconut oil, both the in vitro and In vivo gene transfer efficiencies of such cationic amphiphiles were found to be remarkably superior (>4-fold) to those of their pure dilauroyl analogue. Mechanistic studies involving the technique of fluorescence resonance energy transfer (FRET) revealed higher biomembrane fusibility of the cationic liposomes of the coconut amphiphiles than that of the symmetric dilauroyl analogue. AFM study revealed pronounced fusogenic nonlamellar structures of the liposomes of coconut amphiphiles. Findings in the FRET and cellular uptake study, taken together, support the notion that the higher cellular uptake resulting from the more fusogenic nature of the liposomes of coconut amphiphiles 1 are likely to play a dominant role in making the coconut amphiphiles transfection competent.

  3. Anomalous dielectric response of the copper oxide chains in LiCuVO4

    International Nuclear Information System (INIS)

    Spectroscopic ellipsometry has been used to investigate the low-lying electronic excitations in the strongly correlated chain copper oxide LiCuVO4 in the range 0.7-6.5 eV at temperatures 6 - 350 K. The Zhang-Rice singlet (ZRS) state has been evidenced in edge-sharing copper oxide chains for the first time. Temperature dependence of the ZRS peak identified in the dielectric response along the chains follows spin correlations within the chains that make ZRS apparent at 6 K but strongly suppressed and invisible at 300 K. This behavior is in a good agreement with recent cluster calculations within a pd-Hubbard model. The integrated optical conductivity for polarization along the chains confirms the redistribution of the spectral weight between ZRS and non-bonding O 2p states below 80 K. The corresponding effective number of charge carriers transferred between the states is 0.02 electrons per Cu atom indicating the kinetic energy gain of about 10 meV, which is of the same order of magnitude as the exchange integrals of the competing nearest J1=-2.1 meV and next-nearest J2 = 4.3 meV neighbor interactions. For polarization perpendicular to the chains, no spectral weight transfer between individual bands is observed.

  4. Transferring substrates to the 26S proteasome

    DEFF Research Database (Denmark)

    Hartmann-Petersen, Rasmus; Seeger, Michael; Gordon, Colin

    2003-01-01

    Ubiquitin-dependent protein degradation is not only involved in the recycling of amino acids from damaged or misfolded proteins but also represents an essential and deftly controlled mechanism for modulating the levels of key regulatory proteins. Chains of ubiquitin conjugated to a substrate...... protein specifically target it for degradation by the 26S proteasome, a huge multi-subunit protein complex found in all eukaryotic cells. Recent reports have clarified some of the molecular mechanisms involved in the transfer of ubiquitinated substrates from the ubiquitination machinery to the proteasome...

  5. Benchmarking carbon emissions performance in supply chains

    OpenAIRE

    Acquaye, Adolf; Genovese, Andrea; Barrett, John W.; Koh, Lenny

    2014-01-01

    Purpose – The paper aims to develop a benchmarking framework to address issues such as supply chain complexity and visibility, geographical differences and non-standardized data, ensuring that the entire supply chain environmental impact (in terms of carbon) and resource use for all tiers, including domestic and import flows, are evaluated. Benchmarking has become an important issue in supply chain management practice. However, challenges such as supply chain complexity and visibility, geogra...

  6. Supply chain management in product development.

    OpenAIRE

    Tzortzopoulos, Patricia; Kagioglou, Mike; Cooper, Rachel; Dyson, E

    2009-01-01

    Mounting emphasis on construction supply chain management (CSCM) is due to both global sourcing of materials and a shortage of labor. These factors force increasing amounts of value-added work to be conducted off-site deep in the supply chain. Construction Supply Chain Management Handbookcompiles in one comprehensive source an overview of the diverse research and examples of construction supply chain practice around the world.Reflecting the emergence of CSCM as an important area of multi-nati...

  7. Model Protocells from Single-Chain Lipids

    OpenAIRE

    Mansy, Sheref S.

    2009-01-01

    Significant progress has been made in the construction of laboratory models of protocells. Most frequently the developed vesicle systems utilize single-chain lipids rather than the double-chain lipids typically found in biological membranes. Although single-chain lipids yield less robust vesicles, their dynamic characteristics are highly exploitable for protocellular functions. Herein the advantages of using single-chain lipids in the construction of protocells are discussed.

  8. Model Protocells from Single-Chain Lipids

    Directory of Open Access Journals (Sweden)

    Sheref S. Mansy

    2009-03-01

    Full Text Available Significant progress has been made in the construction of laboratory models of protocells. Most frequently the developed vesicle systems utilize single-chain lipids rather than the double-chain lipids typically found in biological membranes. Although single-chain lipids yield less robust vesicles, their dynamic characteristics are highly exploitable for protocellular functions. Herein the advantages of using single-chain lipids in the construction of protocells are discussed.

  9. Australian Lamb Supply Chain: A Conceptual Framework

    OpenAIRE

    Jie, Ferry

    2011-01-01

    In the last decade, supply chain management has played an important role to lead agribusiness today to succeed in their business goals, to gain competitive advantages, and to improve business performance. As the result of that, there has been extensive studying in a popular topic of strategic supply chain management in order to improve business performance as well as along supply chain performance under the real situation. This is because in current business world, supply chain practices are ...

  10. Kooperationsanforderungen im Supply Chain Management (SCM)

    OpenAIRE

    Klumpp, Matthias; Koppers, Laura

    2007-01-01

    In this paper the general concept of Supply Chain Management (SCM) is described and the scientific cooperation models in the supply chain are discussed. Though there are several models to explain cooperations there is no clear perspective on the needed competencies in companies to shape a successful cooperation e.g. within a supply chain. Instead companies rely solely on experience and intuition in order to create and steer supply chain relationships with high business values. In order to mit...

  11. Model protocells from single-chain lipids.

    Science.gov (United States)

    Mansy, Sheref S

    2009-03-01

    Significant progress has been made in the construction of laboratory models of protocells. Most frequently the developed vesicle systems utilize single-chain lipids rather than the double-chain lipids typically found in biological membranes. Although single-chain lipids yield less robust vesicles, their dynamic characteristics are highly exploitable for protocellular functions. Herein the advantages of using single-chain lipids in the construction of protocells are discussed. PMID:19399223

  12. BUSINESS TENDENCIES IN SERVICES WITHIN SUPPLY CHAIN

    OpenAIRE

    Beata Skowron-Grabowska

    2008-01-01

    Supply chain management has been a major component of competitive strategy to enhance organizational productivity and profitability. Client satisfaction and improvement in profitability are two basic goals while organizing supply chain. In the paper author tried to prove that there is a correlation between organization of supply chain and subjective evaluation of economic situation by enterprises. Logistics integration helps enterprises to find their place in the supply chain.

  13. Supply Chain Integration: Challenges and Solutions

    OpenAIRE

    Sweeney, Edward

    2011-01-01

    Rapid changes in technological development are forcing businesses to continuously innovate to improve their competitiveness, which is particularly evident in logistics and supply chain management (SCM), where innovation impacts both the strategic and operational levels. Supply Chain Innovation for Competing in Highly Dynamic Markets: Challenges and Solutions investigates the role of innovation in the management of supply chains of today. This book focuses on supply chain integration from both...

  14. Linking corporate strategy and supply chain management

    OpenAIRE

    Hofmann, Erik

    2009-01-01

    Purpose of this paper: The paper researches the linkages between corporate and supply chain strategy. It represents a stage of an on-going research initiative aimed at providing a framework for understanding systematically the integration of corporate strategy making and supply chain management. Design/methodology/approach: The paper engaged itself in the theory/literature related to strategic and supply chain management. Four generic levels of strategy are linked to supply chain ma...

  15. Supply Chain Management in the Construction Industry

    OpenAIRE

    Olsson, Fredrik

    2000-01-01

    In this licentiate thesis the implications of a deliberate use of logistics knowledge have been investigated by describing and analyzing the use of a supply chain management approach in the construction industry.
    A five-step approach is used in the thesis. First, theoretical models are developed from the supply chain management literature. Two models are elaborated; One model identifying supply chain criteria and the other comparing traditional to supply chain-based.

  16. A concept for collaborative supply chain planning

    DEFF Research Database (Denmark)

    Alfnes, E.; Dreyer, H.C.; Hvolby, Hans-Henrik;

    2012-01-01

    The main challenge for many manufacturers is the increased complexity of the supply chain, and as supply chains get more complicated enterprises require better tools for supply chain planning and execution. Many vendors offer systems to plan and control in-house operations, whereas mainly large v...... discusses current supply chain planning solutions and presents a more simple and adaptive concept to be used in both SMEs and larger enterprises....

  17. Coupled transfers; Transferts couples

    Energy Technology Data Exchange (ETDEWEB)

    Nicolas, X.; Lauriat, G.; Jimenez-Rondan, J. [Universite de Marne-la-Vallee, Lab. d' Etudes des Transferts d' Energie et de Matiere (LETEM), 77 (France); Bouali, H.; Mezrhab, A. [Faculte des Sciences, Dept. de Physique, Lab. de Mecanique et Energetique, Oujda (Morocco); Abid, C. [Ecole Polytechnique Universitaire de Marseille, IUSTI UMR 6595, 13 Marseille (France); Stoian, M.; Rebay, M.; Lachi, M.; Padet, J. [Faculte des Sciences, Lab. de Thermomecanique, UTAP, 51 - Reims (France); Mladin, E.C. [Universitaire Polytechnique Bucarest, Faculte de Genie Mecanique, Bucarest (Romania); Mezrhab, A. [Faculte des Sciences, Lab. de Mecanique et Energetique, Dept. de Physique, Oujda (Morocco); Abid, C.; Papini, F. [Ecole Polytechnique, IUSTI, 13 - Marseille (France); Lorrette, C.; Goyheneche, J.M.; Boechat, C.; Pailler, R. [Laboratoire des Composites ThermoStructuraux, UMR 5801, 33 - Pessac (France); Ben Salah, M.; Askri, F.; Jemni, A.; Ben Nasrallah, S. [Ecole Nationale d' Ingenieurs de Monastir, Lab. d' Etudes des Systemes Thermiques et Energetiques (Tunisia); Grine, A.; Desmons, J.Y.; Harmand, S. [Laboratoire de Mecanique et d' Energetique, 59 - Valenciennes (France); Radenac, E.; Gressier, J.; Millan, P. [ONERA, 31 - Toulouse (France); Giovannini, A. [Institut de Mecanique des Fluides de Toulouse, 31 (France)

    2005-07-01

    This session about coupled transfers gathers 30 articles dealing with: numerical study of coupled heat transfers inside an alveolar wall; natural convection/radiant heat transfer coupling inside a plugged and ventilated chimney; finite-volume modeling of the convection-conduction coupling in non-stationary regime; numerical study of the natural convection/radiant heat transfer coupling inside a partitioned cavity; modeling of the thermal conductivity of textile reinforced composites: finite element homogenization on a full periodical pattern; application of the control volume method based on non-structured finite elements to the problems of axisymmetrical radiant heat transfers in any geometries; modeling of convective transfers in transient regime on a flat plate; a conservative method for the non-stationary coupling of aero-thermal engineering codes; measurement of coupled heat transfers (forced convection/radiant transfer) inside an horizontal duct; numerical simulation of the combustion of a water-oil emulsion droplet; numerical simulation study of heat and mass transfers inside a reactor for nano-powders synthesis; reduction of a combustion and heat transfer model of a direct injection diesel engine; modeling of heat transfers inside a knocking operated spark ignition engine; heat loss inside an internal combustion engine, thermodynamical and flamelet model, composition effects of CH{sub 4}H{sub 2} mixtures; experimental study and modeling of the evolution of a flame on a solid fuel; heat transfer for laminar subsonic jet of oxygen plasma impacting an obstacle; hydrogen transport through a A-Si:H layer submitted to an hydrogen plasma: temperature effects; thermal modeling of the CO{sub 2} laser welding of a magnesium alloy; radiant heat transfer inside a 3-D environment: application of the finite volume method in association with the CK model; optimization of the infrared baking of two types of powder paints; optimization of the emission power of an infrared

  18. Technology Transfer and Technology Transfer Intermediaries

    Science.gov (United States)

    Bauer, Stephen M.; Flagg, Jennifer L.

    2010-01-01

    A standard and comprehensive model is needed to evaluate and compare technology transfer systems and the stakeholders within these systems. The principle systems considered include federal laboratories, U.S. universities, the rehabilitation engineering research centers (RERCs), and large small business innovation research programs. An earlier…

  19. Magnetic Properties of Quantum Ferrimagnetic Spin Chains

    OpenAIRE

    Yamamoto, Shoji

    1998-01-01

    Magnetic susceptibilities of spin-$(S,s)$ ferrimagnetic Heisenberg chains are numerically investigated. It is argued how the ferromagnetic and antiferromagnetic features of quantum ferrimagnets are exhibited as functions of $(S,s)$. Spin-$(S,s)$ ferrimagnetic chains behave like combinations of spin-$(S-s)$ ferromagnetic and spin-$(2s)$ antiferromagnetic chains provided $S=2s$.

  20. Secure Supply Chains: Design Restrictions & Organizational Boundaries

    NARCIS (Netherlands)

    Ludema, M.W.

    2009-01-01

    An important issue in the design of secure supply chains is the understanding of the relation between supply chains and the organizational responsibility of specific parts of these supply chains. Organizational boundaries change over time by means of vertical and/or horizontal (des)-integration and