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Sample records for plastic rp experimental

  1. Macrophage plasticity in experimental atherosclerosis.

    Directory of Open Access Journals (Sweden)

    Jamila Khallou-Laschet

    Full Text Available As in human disease, macrophages (MØ are central players in the development and progression of experimental atherosclerosis. In this study we have evaluated the phenotype of MØ associated with progression of atherosclerosis in the apolipoprotein E (ApoE knockout (KO mouse model.We found that bone marrow-derived MØ submitted to M1 and M2 polarization specifically expressed arginase (Arg II and Arg I, respectively. This distinct arginase expression was used to evaluate the frequency and distribution of M1 and M2 MØ in cross-sections of atherosclerotic plaques of ApoE KO mice. Early lesions were infiltrated by Arg I(+ (M2 MØ. This type of MØ favored the proliferation of smooth muscle cells, in vitro. Arg II(+ (M1 MØ appeared and prevailed in lesions of aged ApoE KO mice and lesion progression was correlated with the dominance of M1 over the M2 MØ phenotype. In order to address whether the M2->M1 switch could be due to a phenotypic switch of the infiltrated cells, we performed in vitro repolarization experiments. We found that fully polarized MØ retained their plasticity since they could revert their phenotype. The analysis of the distribution of Arg I- and Arg II-expressing MØ also argued against a recent recruitment of M1 MØ in the lesion. The combined data therefore suggest that the M2->M1 switch observed in vivo is due to a conversion of cells already present in the lesion. Our study suggests that interventional tools able to revert the MØ infiltrate towards the M2 phenotype may exert an atheroprotective action.

  2. Experimental determination of nuclear parameters for RP-0 reactor core; Determinacion experimental de los parametros nucleares para el nucleo tipo MTR del reactor nuclear RP-0

    Energy Technology Data Exchange (ETDEWEB)

    Cajacuri, Rafael A. [Sao Paulo Univ., SP (Brazil). Inst. de Fisica

    2000-07-01

    In the nuclear reactor for investigations RP-0 which is in Lima, Peru, that is a open pool class reactor with 1 to 10 watts of power and as a nuclear fuel uranium 238 enriched to 20% constituted by elements of Material Testing Reactor fuel class. This has reflectors of graphite and moderator of water demineralized. In 1996/1997 was measured in this reactor the following parameters: position of the control bar that make critic the reactor, critic height of moderator, excess of reactivity of the nucleus, parameter of reactivity for vacuum, parameter of reactivity for temperature, reactivity of its control bar, levels of doses in the reactor. (author)

  3. Nucleosynthesis of proton-rich nuclei. Experimental results on the rp-process

    Energy Technology Data Exchange (ETDEWEB)

    Galaviz, D [Centro de Fisica Nuclear da Universidade de Lisboa, 1070-325 Lisbon (Portugal); Amthor, A M; Bazin, D; Becerril, A D; Brown, B A; Cole, A; Cook, J M; Elliot, T; Estrade, A; Gade, A; Glasmacher, T; Lorusso, G; Matos, M; Montes, F; Mueller, W [National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824 (United States); Chen, A A [Department of Physics and Astronomy, McMaster University, Hamilton, ON L8S 4M1 (Canada); Fueloep, Z S [ATOMKI, H-4001 Debrecen, POB. 51 (Hungary); Heger, A [Joint Institute for Nuclear Astrophysics, Michigan State University, East Lansing, Michigan 48824 (United States); Howard, M E [Department of Physics, Ohio State University, Columbus, Ohio 43210 (United States); Kessler, R, E-mail: galaviz@cii.fc.ul.p [Institut fuer Kernchemie, University of Mainz, D-55128 Mainz (Germany)

    2010-01-01

    We report in this study the nuclear properties of proton-rich isotopes located along the rp-process path. The experiments have recently been performed at the National Superconducting Cyclotron Laboratory (NSCL) at Michigan State University. The level properties above the proton separation energy of the nuclei {sup 30}S, {sup 36}K and {sup 37}Ca were measured with precision of < 10 keV. This will allow a reduction in the determination of the astrophysical (p,{gamma}) reaction rate under rp-process conditions.

  4. Nucleosynthesis of proton-rich nuclei. Experimental results on the rp-process

    Science.gov (United States)

    Galaviz, D.; Amthor, A. M.; Bazin, D.; Becerril, A. D.; Brown, B. A.; Chen, A. A.; Cole, A.; Cook, J. M.; Elliot, T.; Estrade, A.; Fülöp, Z. S.; Gade, A.; Glasmacher, T.; Heger, A.; Howard, M. E.; Kessler, R.; Lorusso, G.; Matos, M.; Montes, F.; Müller, W.; Pereira, J.; Schatz, H.; Sherrill, B.; Schertz, F.; Shimbara, Y.; Smith, E.; Smith, K.; Tamii, A.; Stolz, A.; Weisshaar, D.; Wallace, M.; Wiescher, M.; Zegers, R. G. T.

    2010-01-01

    We report in this study the nuclear properties of proton-rich isotopes located along the rp-process path. The experiments have recently been performed at the National Superconducting Cyclotron Laboratory (NSCL) at Michigan State University. The level properties above the proton separation energy of the nuclei 30S, 36K and 37Ca were measured with precision of < 10 keV. This will allow a reduction in the determination of the astrophysical (p,γ) reaction rate under rp-process conditions.

  5. Experimental and Numerical Investigations of RP-2 Under High Heat Fluxes

    Science.gov (United States)

    2007-05-01

    well-known Dittus-Boelter and Sieder -Tate correlations and the NASA/GRC correlation of Stiegemeier et. al is presented for Reynolds numbers between...Boelter and Sieder -Tate correlations and the NASA/GRC correlation of Stiegemeier et. al is presented for Reynolds numbers between 5,000-35,000...530 psi 165 ft/s, 1720 psi Nu, Dittus-Boelter Nu, Sieder -Tate Nu, NASA-GRC 2002 Figure 3. Comparison of experimental data with existing heat

  6. Studies on Log Po/w of Quinoxaline di-N-Oxides: A Comparison of RP-HPLC Experimental and Predictive Approaches

    Directory of Open Access Journals (Sweden)

    James A. Platts

    2011-09-01

    Full Text Available As reported in our previous papers, a series of quinoxaline-2-carboxamide 1,4-di-N-oxide derivatives were synthesized and studied as anti-tuberculosis agents. Here, the capability of the shake-flask method was studied and the retention time (expressed as log K of 20 compounds were determined by RP-HPLC analysis. We found that the prediction of log P by the RP-HPLC analysis can result in a high accuracy and can replace the shake-flask method avoiding the experimental problems presented by quinoxaline di-N-oxides. The studied compounds were subjected to the ALOGPS module with the aim of comparing experimental log Po/w values and predicted data. Moreover, a preliminary in silico screening of the QSAR relationship was made confirming the influence of reduction peak potential, lipophilicity, H-bond donor capacity and molecular dimension descriptors on anti-tuberculosis activity.

  7. Inflammation subverts hippocampal synaptic plasticity in experimental multiple sclerosis.

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    Robert Nisticò

    Full Text Available Abnormal use-dependent synaptic plasticity is universally accepted as the main physiological correlate of memory deficits in neurodegenerative disorders. It is unclear whether synaptic plasticity deficits take place during neuroinflammatory diseases, such as multiple sclerosis (MS and its mouse model, experimental autoimmune encephalomyelitis (EAE. In EAE mice, we found significant alterations of synaptic plasticity rules in the hippocampus. When compared to control mice, in fact, hippocampal long-term potentiation (LTP induction was favored over long-term depression (LTD in EAE, as shown by a significant rightward shift in the frequency-synaptic response function. Notably, LTP induction was also enhanced in hippocampal slices from control mice following interleukin-1β (IL-1β perfusion, and both EAE and IL-1β inhibited GABAergic spontaneous inhibitory postsynaptic currents (sIPSC without affecting glutamatergic transmission and AMPA/NMDA ratio. EAE was also associated with selective loss of GABAergic interneurons and with reduced gamma-frequency oscillations in the CA1 region of the hippocampus. Finally, we provided evidence that microglial activation in the EAE hippocampus was associated with IL-1β expression, and hippocampal slices from control mice incubated with activated microglia displayed alterations of GABAergic transmission similar to those seen in EAE brains, through a mechanism dependent on enhanced IL-1β signaling. These data may yield novel insights into the basis of cognitive deficits in EAE and possibly of MS.

  8. Corticostriatal Plastic Changes in Experimental L-DOPA-Induced Dyskinesia

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    Veronica Ghiglieri

    2012-01-01

    Full Text Available In Parkinson’s disease (PD, alteration of dopamine- (DA- dependent striatal functions and pulsatile stimulation of DA receptors caused by the discontinuous administration of levodopa (L-DOPA lead to a complex cascade of events affecting the postsynaptic striatal neurons that might account for the appearance of L-DOPA-induced dyskinesia (LID. Experimental models of LID have been widely used and extensively characterized in rodents and electrophysiological studies provided remarkable insights into the inner mechanisms underlying L-DOPA-induced corticostriatal plastic changes. Here we provide an overview of recent findings that represent a further step into the comprehension of mechanisms underlying maladaptive changes of basal ganglia functions in response to L-DOPA and associated to development of LID.

  9. Phenotypic plasticity is not affected by experimental evolution in constant, predictable or unpredictable fluctuating thermal environments.

    Science.gov (United States)

    Manenti, T; Loeschcke, V; Moghadam, N N; Sørensen, J G

    2015-11-01

    The selective past of populations is presumed to affect the levels of phenotypic plasticity. Experimental evolution at constant temperatures is generally expected to lead to a decreased level of plasticity due to presumed costs associated with phenotypic plasticity when not needed. In this study, we investigated the effect of experimental evolution in constant, predictable and unpredictable daily fluctuating temperature regimes on the levels of phenotype plasticity in several life history and stress resistance traits in Drosophila simulans. Contrary to the expectation, evolution in the different regimes did not affect the levels of plasticity in any of the traits investigated even though the populations from the different thermal regimes had evolved different stress resistance and fitness trait means. Although costs associated with phenotypic plasticity are known, our results suggest that the maintenance of phenotypic plasticity might come at low and negligible costs, and thus, the potential of phenotypic plasticity to evolve in populations exposed to different environmental conditions might be limited.

  10. Application of experimental design and response surface technique for selecting the optimum RP-HPLC conditions for the determination of moxifloxacin HCl and ketorolac tromethamine in eye drops

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    Pradipbhai D. Kalariya

    2017-01-01

    Full Text Available A method has been developed for the separation of moxifloxacin HCl and ketorolac tromethamine using reverse phase high-performance liquid chromatography (RP-HPLC on C18 column (250 × 4.6 mm, 5 μm with UV detection at 308 nm. Experimental designs were applied for multivariate optimization of the experimental conditions of RP-HPLC method. Three independent factors: methanol content in the mobile phase composition, buffer pH and flow rate were used to design mathematical models. Here faced central composite (FCC experimental design was used to study the response surface technique and to study in depth the effects of these independent factors. Derringer’s desirability function was applied to simultaneously optimize the retention time of last eluting peak (ketorolac tromethamine and tailing factor of moxifloxacin. The predicted optimum assay condition consisted of methanol and potassium dihydrogen phosphate buffer (pH 3.2; 25 mM, 0.5% Triethylamine in a proportion of 60:40% v/v, respectively, as the mobile phase at a flow rate of 1.2 mL min−1. Using this optimum condition, baseline separation of both drugs with good resolution and a run time of less than 7 min were achieved. The optimized assay condition was validated according to ICH guidelines to confirm specificity, linearity, accuracy and precision.

  11. Experimental assessment of unvalidated assumptions in classical plasticity theory.

    Energy Technology Data Exchange (ETDEWEB)

    Brannon, Rebecca Moss (University of Utah, Salt Lake City, UT); Burghardt, Jeffrey A. (University of Utah, Salt Lake City, UT); Bauer, Stephen J.; Bronowski, David R.

    2009-01-01

    This report investigates the validity of several key assumptions in classical plasticity theory regarding material response to changes in the loading direction. Three metals, two rock types, and one ceramic were subjected to non-standard loading directions, and the resulting strain response increments were displayed in Gudehus diagrams to illustrate the approximation error of classical plasticity theories. A rigorous mathematical framework for fitting classical theories to the data, thus quantifying the error, is provided. Further data analysis techniques are presented that allow testing for the effect of changes in loading direction without having to use a new sample and for inferring the yield normal and flow directions without having to measure the yield surface. Though the data are inconclusive, there is indication that classical, incrementally linear, plasticity theory may be inadequate over a certain range of loading directions. This range of loading directions also coincides with loading directions that are known to produce a physically inadmissible instability for any nonassociative plasticity model.

  12. Evaluation Of Gas Diffusion Through Plastic Materials Used In Experimental And Sampling Equipment

    DEFF Research Database (Denmark)

    Kjeldsen, Peter

    1993-01-01

    Plastic materials are often used in experimental and sampling equipment. Plastics are not gas tight, since gases are able to diffuse through the walls of tubing and containers made of plastic. Methods for calculating the significance of gas diffusion through the walls of containers and the walls....... Calculations show that diffusion of oxygen through plastic tubing and reactors into anoxic water can be a serious problem for a series of plastic materials. Comparison of the method for turbulent and laminar flow in tubings shows that the difference is insignificant for most cases. Calculations show also...... that the use of silicone rubber in experimental and sampling equipment to be used for anoxic water is, for most cases, prohibited by oxygen diffusion....

  13. An experimental study of plastic deformation of materials

    DEFF Research Database (Denmark)

    Knudsen, Tine

    in the investigated hot deformed samples (lnZ= 27.5 to 32) in general are cell block structures, and that the alignment of the cell block boundaries at low strain depends on the grain orientation, often in the same manner as in cold deformation. Part II investigates the energy stored in the dislocation structure...... after cold deformation by calorimetry and by analysis of the dislocation structure. The stored energy measured by calorimetry is found to be larger than that determined from the dislocation structure by a factor between 1.9 and 2.7, and this factor decreases with the plastic strain. Part III aimed...

  14. Multiscale simulation and nanoindentation experimental study of initial plasticity of Fe single crystal

    Institute of Scientific and Technical Information of China (English)

    YUAN Lin; SHAN De-bin; GUO Bin

    2009-01-01

    It is very important to understand the initial plastic behavior of metals at microscale. In order to research the initial plasticity of body centered cubic metals in micro-/nano-scale, the multiscale simulation method and experimental study were used to study the nanoindentation process of Fe single crystal. The results show that the first abruption of load-displacement curve in nanoindentation of Fe single crystal can be attributed to the first transition from elastic to plastic deformation characterized by the dislocation emission.

  15. Experimental tests for heritable morphological color plasticity in non-native brown trout (Salmo trutta populations.

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    Peter A H Westley

    Full Text Available The success of invasive species is frequently attributed to phenotypic plasticity, which facilitates persistence in novel environments. Here we report on experimental tests to determine whether the intensity of cryptic coloration patterns in a global invader (brown trout, Salmo trutta was primarily the result of plasticity or heritable variation. Juvenile F1 offspring were created through experimental crosses of wild-caught parents and reared for 30 days in the laboratory in a split-brood design on either light or dark-colored gravel substrate. Skin and fin coloration quantified with digital photography and image analysis indicated strong plastic effects in response to substrate color; individuals reared on dark substrate had both darker melanin-based skin color and carotenoid-based fin colors than other members of their population reared on light substrate. Slopes of skin and fin color reaction norms were parallel between environments, which is not consistent with heritable population-level plasticity to substrate color. Similarly, we observed weak differences in population-level color within an environment, again suggesting little genetic control on the intensity of skin and fin colors. Taken as whole, our results are consistent with the hypothesis that phenotypic plasticity may have facilitated the success of brown trout invasions and suggests that plasticity is the most likely explanation for the variation in color intensity observed among these populations in nature.

  16. A Stability Formula for Plastic-Tipped Bullets Part 2: Experimental Testing

    CERN Document Server

    Courtney, Michael W

    2014-01-01

    Part 1 of this paper describes a modification of the original Miller twist rule for computing gyroscopic bullet stability that is better suited to plastic-tipped bullets. The original Miller twist rule assumes a bullet of constant density, but it also works well for conventional copper (or gilding metal) jacketed lead bullets because the density of copper and lead are sufficiently close. However, the original Miller twist rule significantly underestimates the gyroscopic stability of plastic-tipped bullets, because the density of plastic is much lower than the density of copper and lead. Here, a new amended formula is developed for the gyroscopic stability of plastic-tipped bullets by substituting the length of just the metal portion for the total length in the (1 + L2) term of the original Miller twist rule. Part 2 describes experimental testing of this new formula on three plastic-tipped bullets. The new formula is relatively accurate for plastic-tipped bullets whose metal portion has nearly uniform density,...

  17. Experimental Investigation of Fully Plastic Contact of a Sphere Against a Hard Flat

    NARCIS (Netherlands)

    Jamari, J.; Schipper, D.J.

    2006-01-01

    In this paper we report the experimental investigation to evaluate the published models for the contact of a deformable sphere against a hard flat in the fully plastic contact regime. A new measurement method has been used to measure the contact area. The behavior of the mean contact pressure and th

  18. Specific heat and thermal conductivity of explosives, mixtures, and plastic-bonded explosives determined experimentally

    Energy Technology Data Exchange (ETDEWEB)

    Baytos, J.F.

    1979-09-01

    The specific heat and thermal conductivity of explosives and plastic-bonded explosives of interest to WX operations, determined experimentally, are reported in three tables. Specific heat was determined by differential scanning calorimetry against sapphire standards. Thermal conductivity was determined by two means: the guarded hot-plate method or the differential scanning calorimeter comparative method on miniature samples.

  19. Phenotypic plasticity changes correlations of traits following experimental introductions of Trinidadian guppies (Poecilia reticulata).

    Science.gov (United States)

    Handelsman, Corey A; Ruell, Emily W; Torres-Dowdall, Julián; Ghalambor, Cameron K

    2014-11-01

    Colonization of novel environments can alter selective pressures and act as a catalyst for rapid evolution in nature. Theory and empirical studies suggest that the ability of a population to exhibit an adaptive evolutionary response to novel selection pressures should reflect the presence of sufficient additive genetic variance and covariance for individual and correlated traits. As correlated traits should not respond to selection independently, the structure of correlations of traits can bias or constrain adaptive evolution. Models of how multiple correlated traits respond to selection often assume spatial and temporal stability of trait-correlations within populations. Yet, trait-correlations can also be plastic in response to environmental variation. Phenotypic plasticity, the ability of a single genotype to produce different phenotypes across environments, is of particular interest because it can induce population-wide changes in the combination of traits exposed to selection and change the trajectory of evolutionary divergence. We tested the ability of phenotypic plasticity to modify trait-correlations by comparing phenotypic variance and covariance in the body-shapes of four experimental populations of Trinidadian guppies (Poecilia reticulata) to their ancestral population. We found that phenotypic plasticity produced both adaptive and novel aspects of body-shape, which was repeated in all four experimental populations. Further, phenotypic plasticity changed patterns of covariance among morphological characters. These findings suggest our ability to make inferences about patterns of divergence based on correlations of traits in extant populations may be limited if novel environments not only induce plasticity in multiple traits, but also change the correlations among the traits.

  20. Experimental investigations and numerical simulations of notch effect in cellular plastic materials

    Science.gov (United States)

    Marsavina, L.; Linul, E.; Voiconi, T.; Negru, R.

    2016-04-01

    Cellular plastics are light weight structures with many applications in civil, aeronautical, automotive and mechanical engineering. Properties of cellular materials depend on the properties of the solid material, on the shape and dimensions of the cellular structure and on the relative density of the cellular material. Most of cellular plastic materials are crushing in compression and have a brittle behavior in tension. The effect of notches represents an important issue in such materials, taking into account that for packing applications for example, notches/holes should be introduced in the cellular material. This paper investigates the effect of notches in compression for three different densities 100, 145 and 300 kg/m3 polyurethane (PUR) foams. Experimental investigations were performed on rectangular blocks of 100×100×25 mm with 16, 28 and 40 mm central holes. The mechanism of damage was monitored with an IR camera FLIR A40M. Purpose of the numerical simulations was to calibrate a material model, based on compression test for un-notched specimens using the CRUSHABLE FOAM models implemented in ABAQUS SIMULIA. Then the material models were used to simulate the experimental tests on notched blocks. Good agreement was obtained for the load - displacement curves obtained experimentally and from simulation. Also the plastic deformation patterns observed experimentally by IR thermograpghy were obtained numerically using the CRUSHABLE FOAM material model.

  1. Theoretical and experimental characterization of novel water-equivalent plastics in clinical high-energy carbon-ion beams

    Science.gov (United States)

    Lourenço, A.; Wellock, N.; Thomas, R.; Homer, M.; Bouchard, H.; Kanai, T.; MacDougall, N.; Royle, G.; Palmans, H.

    2016-11-01

    Water-equivalent plastics are frequently used in dosimetry for experimental simplicity. This work evaluates the water-equivalence of novel water-equivalent plastics specifically designed for light-ion beams, as well as commercially available plastics in a clinical high-energy carbon-ion beam. A plastic- to-water conversion factor {{H}\\text{pl,w}} was established to derive absorbed dose to water in a water phantom from ionization chamber readings performed in a plastic phantom. Three trial plastic materials with varying atomic compositions were produced and experimentally characterized in a high-energy carbon-ion beam. Measurements were performed with a Roos ionization chamber, using a broad un-modulated beam of 11  ×  11 cm2, to measure the plastic-to-water conversion factor for the novel materials. The experimental results were compared with Monte Carlo simulations. Commercially available plastics were also simulated for comparison with the plastics tested experimentally, with particular attention to the influence of nuclear interaction cross sections. The measured H\\text{pl,w}\\exp correction increased gradually from 0% at the surface to 0.7% at a depth near the Bragg peak for one of the plastics prepared in this work, while for the other two plastics a maximum correction of 0.8%-1.3% was found. Average differences between experimental and numerical simulations were 0.2%. Monte Carlo results showed that for polyethylene, polystyrene, Rando phantom soft tissue and A-150, the correction increased from 0% to 2.5%-4.0% with depth, while for PMMA it increased to 2%. Water-equivalent plastics such as, Plastic Water, RMI-457, Gammex 457-CTG, WT1 and Virtual Water, gave similar results where maximum corrections were of the order of 2%. Considering the results from Monte Carlo simulations, one of the novel plastics was found to be superior in comparison with the plastic materials currently used in dosimetry, demonstrating that it is feasible to tailor plastic

  2. Experimental operation of the production line for carbon fiber-reinforced plastic

    Energy Technology Data Exchange (ETDEWEB)

    Boldin, V.M.; Denezhkin, N.M.; Krivoshchekova, N.P.; Krotova, Z.S.; Yermakov, V.F.

    1979-01-01

    Verifications of the quality of the manufactured tubings established that in physical-mechanical indicators the carbon fiber-reinforced plastic corresponds to the requirements which are made for the material of the timbering rising, operated in the zone of intensive manifestation of mine pressure, and exposed to the effect of a stream of coal transmitted through it. Average data are presented for physical-mechanical properties of the carbon fiber-reinforced plastic according to samples manufactured from the tubings. In 1974-1978 the production line produced over 130,000 tubings, or 6600m of timbering to two type-sizes with inner diameter of 850 and 1090 mm. Experimental operation of the production line indicated that as a whole it is efficient, simple and convenient to operate, and guarantees safe working conditions of the service personnel. Verification and pinpointing of the production parameters for making timbering, as well as generalization of the experience of operating the line made it possible to plan a production line with maximum mechanization and automation of the operations of the production process and increase its productivity two-fold. The production line will be put into operation in 1980 in the experimental shop TsEMM No 4 of the production association ''Prokop'yevskugol'.''

  3. Experimental Investigation into Suitable Process Conditions for Plastic Injection Molding of Thin-Sheet Parts

    Directory of Open Access Journals (Sweden)

    Dyi-Cheng Chen

    2014-04-01

    Full Text Available This study performs an experimental investigation into the effects of the process parameters on the surface quality of injection molded thin-sheet thermoplastic components. The investigations focus specifically on the shape, number and position of the mold gates, the injection pressure and the injection rate. It can be seen that the gravity force entering point improved filling of the cavity for the same forming time and injection pressure. Moreover, it shows the same injection pressure and packing time, the taper-shape gate yields a better surface appearance than the sheet-shape gate. The experimental results provide a useful source of reference in suitable the process conditions for the injection molding of thin-sheet plastic components.

  4. Development and Validation of a Rapid RP-HPLC Method for the Determination of Venlafaxine Hydrochloride in Pharmaceutical Dosage forms using Experimental Design

    Directory of Open Access Journals (Sweden)

    Vanita Somasekhar

    2009-01-01

    Full Text Available The objective of the current study was to develop a simple, accurate, precise and rapid reversed-phase HPLC method and subsequent validation as per ICH guidelines for the determination of venlafaxine hydrochloride in pharmaceutical dosage forms. The proposed RP-HPLC method utilizes a 5 μm Varian® Microsorb-MV 100 C18 column (250 mmx4.6 mm at ambient temperature. A 23 factorial design consisting of 3 factors at 2 levels was set up to standardize the chromatographic conditions. A numerical optimization technique employing the desirability approach was used to locate the optimum chromatographic conditions. The optimum mobile phase consisted of acetonitrile, 0.04 M potassium dihydrogen phosphate buffer and methanol (45:25:30, v/v, with pH adjusted to 5.5 using 10% phosphoric acid solution. The mobile phase was delivered isocratically at a flow rate of 1 mL/min with UV detection at 224 nm. The calibration plots constructed using the optimized chromatographic conditions displayed good linear relationship in the concentration range of 1-50 μg/mL with r=0.9992. The method was validated for precision, accuracy, robustness and recovery. The minimum detectable and minimum quantifiable amounts were found to be 0.568 and 1.72 μg/mL, respectively and the method was found to be reproducible from the statistical data generated. Venlafaxine hydrochloride was eluted at 3.43 min

  5. Experimental investigation of supersonic radiation propagation in low-density plastic and copper-doped foams

    Institute of Scientific and Technical Information of China (English)

    JIANG; Shaoen; XU; Yan; DING; Yongkun; LAI; Dongxian; ZHEN

    2005-01-01

    Eight beams of 0.35 μm laser with pulse duration of 1 ns and total energy of 2 kJ enter into a hohlraum to create intense X-ray radiation of 140 eV on the Shenguang Ⅱ laser facility. Plastic foam (C6H12) and copper-doped foam (C6H12Cu0.394) with a density of 50 mg/cm3 are heated by X-ray radiation emitted from the hohlraum. The breakout time of the radiation wave is measured by a tri-chromatic streaked X-ray spectrometer (TCS) that consists of a set of three imaging pinholes and an array of three transmission gratings coupled with an X-ray streak camera (XSC). At one shot, the simultaneous measurements of the delay of the drive source and the radiation transport at two energies (210 eV, 840 eV) through the foam have been made for the first time. The experimental results indicate that the time delays vary with photon energies. With a transmission grating spectrometer (TGS), the spectra transmitting foams were measured, and the lower limit of the optical depth was measured. The radiation at energy of 210 eV propagates through plastic foam at a faster velocity, compared with the radiation at energy of 840 eV; while the results of copper-doped foam are reverse. The optical depth in the plastic foam is less than 1, and in the doped foam it is more than 1.

  6. Parametric and non-parametric modeling of short-term synaptic plasticity. Part II: Experimental study.

    Science.gov (United States)

    Song, Dong; Wang, Zhuo; Marmarelis, Vasilis Z; Berger, Theodore W

    2009-02-01

    This paper presents a synergistic parametric and non-parametric modeling study of short-term plasticity (STP) in the Schaffer collateral to hippocampal CA1 pyramidal neuron (SC) synapse. Parametric models in the form of sets of differential and algebraic equations have been proposed on the basis of the current understanding of biological mechanisms active within the system. Non-parametric Poisson-Volterra models are obtained herein from broadband experimental input-output data. The non-parametric model is shown to provide better prediction of the experimental output than a parametric model with a single set of facilitation/depression (FD) process. The parametric model is then validated in terms of its input-output transformational properties using the non-parametric model since the latter constitutes a canonical and more complete representation of the synaptic nonlinear dynamics. Furthermore, discrepancies between the experimentally-derived non-parametric model and the equivalent non-parametric model of the parametric model suggest the presence of multiple FD processes in the SC synapses. Inclusion of an additional set of FD process in the parametric model makes it replicate better the characteristics of the experimentally-derived non-parametric model. This improved parametric model in turn provides the requisite biological interpretability that the non-parametric model lacks.

  7. Assessing the suitability of recycled plastics used as agricultural soil covers: migration study and experimental harvest.

    Science.gov (United States)

    Nerín, C; Batlle, R

    1999-01-01

    The present work is focused on evaluating the suitability of recycling postconsumer agricultural plastic films again for the same use. The criteria to assess the suitability was based on migration study. Both overall and specific migration tests were performed, and the results obtained (ranging from 0.14 to 1.27 mg/dm(2) for overall migration and from not detectable to 6.98 microg/dm(2) for specific migration) show how, from this point of view, the recycled material can be safely proposed to be used again as agricultural soil covers. A theoretical discussion about the migration process is also presented and a simple mathematical model was applied to the data obtained, showing how total migration which is experimentally detected is theoretically predictable. These conclusions found were used to design and develop a controlled crop of tomato by using this recycled film. The use of the recycled plastic in the whole process and the behavior and properties of the pesticides absorbed in the postconsumer film are discussed.

  8. Experimental investigation of the reaction-build-up for plastic bonded explosive JOB-9003

    Directory of Open Access Journals (Sweden)

    Xu Zhang

    2017-05-01

    Full Text Available In order to measure the shock initiation behavior of JOB-9003 explosives, Al-based embedded multiple electromagnetic particle velocity gauge technique has been developed. In addition, a gauge element called the shock tracker has been used to monitor the progress of the shock front as a function of time, thus providing a position–time trajectory of the wave front as it moves through the explosive sample. The data is used to determine the position and time for shock to detonation transition. All the experimental results show that the rising-up time of Al-based electromagnetic particle velocity gauge is very short (<20 ns; the reaction-build-up velocity profiles and the position–time for shock to detonation transition of HMX-based plastic bonded explosive (PBX JOB-9003 with 1–8 mm depth from the origin of the impact plane under different initiation pressures were obtained with high accuracy.

  9. Aging and demographic plasticity in response to experimental age structures in honeybees (Apis mellifera L).

    Science.gov (United States)

    Rueppell, Olav; Linford, Robyn; Gardner, Preston; Coleman, Jennifer; Fine, Kari

    2008-08-01

    Honeybee colonies are highly integrated functional units characterized by a pronounced division of labor. Division of labor among workers is mainly age-based, with younger individuals focusing on in-hive tasks and older workers performing the more hazardous foraging activities. Thus, experimental disruption of the age composition of the worker hive population is expected to have profound consequences for colony function. Adaptive demography theory predicts that the natural hive age composition represents a colony-level adaptation and thus results in optimal hive performance. Alternatively, the hive age composition may be an epiphenomenon, resulting from individual life history optimization. We addressed these predictions by comparing individual worker longevity and brood production in hives that were composed of a single age cohort, two distinct age cohorts, and hives that had a continuous, natural age distribution. Four experimental replicates showed that colonies with a natural age composition did not consistently have a higher life expectancy and/or brood production than the single cohort or double cohort hives. Instead, a complex interplay of age structure, environmental conditions, colony size, brood production, and individual mortality emerged. A general trade-off between worker life expectancy and colony productivity was apparent, and the transition from in-hive tasks to foraging was the most significant predictor of worker lifespan irrespective of the colony age structure. We conclude that the natural age structure of honeybee hives is not a colony-level adaptation. Furthermore, our results show that honeybees exhibit pronounced demographic plasticity in addition to behavioral plasticity to react to demographic disturbances of their societies.

  10. Phenotypic plasticity of hermaphrodite sex allocation promotes the evolution of separate sexes: an experimental test of the sex-differential plasticity hypothesis using Sagittaria latifolia (Alismataceae).

    Science.gov (United States)

    Dorken, Marcel E; Mitchard, Edward T A

    2008-04-01

    Separate sexes can evolve under nuclear inheritance when unisexuals have more than twice the reproductive fitness of hermaphrodites through one sex function (e.g., when females have more than twice the seed fertility of hermaphrodites). Because separate sexes are thought to evolve most commonly via a gynodioecious intermediate (i.e., populations in which females and hermaphrodites cooccur), the conditions under which females can become established in populations of hermaphrodites are of considerable interest. It has been proposed that resource-poor conditions could promote the establishment of females if hermaphrodites are plastic in their sex allocation and allocate fewer resources to seed production under these conditions. If this occurs, the seed fertility of females could exceed the doubling required for the evolution of unisexuality under low-, but not high-resource conditions (the sex-differential plasticity hypothesis). We tested this hypothesis using replicate experimental arrays of the aquatic herb Sagittaria latifolia grown under two fertilizer treatments. The results supported the sex-differential plasticity hypothesis, with females having more than twice the seed fertility of hermaphrodites under low-, but not high-fertilizer conditions. Our findings are consistent with the idea that separate sexes are more likely to evolve under unfavorable conditions.

  11. Experimental Evidence Shows the Importance of Behavioural Plasticity and Body Size under Competition in Waterfowl

    Science.gov (United States)

    Zhang, Yong; Prins, Herbert H. T.; Versluijs, Martijn; Wessels, Rick; Cao, Lei; de Boer, Willem Frederik

    2016-01-01

    When differently sized species feed on the same resources, interference competition may occur, which may negatively affect their food intake rate. It is expected that competition between species also alters behaviour and feeding patch selection. To assess these changes in behaviour and patch selection, we applied an experimental approach using captive birds of three differently sized Anatidae species: wigeon (Anas penelope) (~600 g), swan goose (Anser cygnoides) (~2700 g) and bean goose (Anser fabalis) (~3200 g). We quantified the functional response for each species and then recorded their behaviour and patch selection with and without potential competitors, using different species combinations. Our results showed that all three species acquired the highest nitrogen intake at relatively tall swards (6, 9 cm) when foraging in single species flocks in the functional response experiment. Goose species were offered foraging patches differing in sward height with and without competitors, and we tested for the effect of competition on foraging behaviour. The mean percentage of time spent feeding and being vigilant did not change under competition for all species. However, all species utilized strategies that increased their peck rate on patches across different sward heights, resulting in the same instantaneous and nitrogen intake rate. Our results suggest that variation in peck rate over different swards height permits Anatidae herbivores to compensate for the loss of intake under competition, illustrating the importance of behavioural plasticity in heterogeneous environments when competing with other species for resources. PMID:27727315

  12. Experimental Studies on Improved Plastic Bonded Explosives Materials (PBXs for Controlled Fragmentation Warheads

    Directory of Open Access Journals (Sweden)

    Elsharkawy Karim

    2017-01-01

    Full Text Available This paper describes formulations of plastic bonded explosives (PBXs based on three highly brisant explosives, namely 1,3,5-trinitro-1,3,5-triazinane (RDX, 1,3,5,7-tetranitro-1,3,5,7-tetrazocane (HMX and pentaerythritoltetranitrate (PETN with polyurethane (PU based on Glycidyl azide polymer (GAP as an energetic binder in comparison with composition-B, which used in the fragmentation warheads. The sensitivity and performance properties of different types of PBXs were evaluated by experimental results of prepared selected PBX compositions. Casting technique was used to prepare the selected compositions containing 14% PU based on GAP. It has been observed that the brisance of the PBX based on HMX was higher than that of comp-B by 21.3 %, the detonation velocity showed a remarkable increase of the order of 8480 (m/s while that of comp-B was 7638 (m/s. A controlled fragmentation warhead with an outer grooving warhead case of dimensions 100x35x4 mm was used and arena test was carried out to determine the lethal zone of the fragmentation warhead. The lethal zone obtained from arena test for PBX composition based on HMX named PBXHG4 was higher than that based on RDX or PETN, and than that of comp-B by 40%.

  13. Experimental febrile seizures induce age-dependent structural plasticity and improve memory in mice.

    Science.gov (United States)

    Tao, K; Ichikawa, J; Matsuki, N; Ikegaya, Y; Koyama, R

    2016-03-24

    Population-based studies have demonstrated that children with a history of febrile seizure (FS) perform better than age-matched controls at hippocampus-dependent memory tasks. Here, we report that FSs induce two distinct structural reorganizations in the hippocampus and bidirectionally modify future learning abilities in an age-dependent manner. Compared with age-matched controls, adult mice that had experienced experimental FSs induced by hyperthermia (HT) on postnatal day 14 (P14-HT) performed better in a cognitive task that requires dentate granule cells (DGCs). The enhanced memory performance correlated with an FS-induced persistent increase in the density of large mossy fiber terminals (LMTs) of the DGCs. The memory enhancement was not observed in mice that had experienced HT-induced seizures at P11 which exhibited abnormally located DGCs in addition to the increased LMT density. The ectopic DGCs of the P11-HT mice were abolished by the diuretic bumetanide, and this pharmacological treatment unveiled the masked memory enhancement. Thus, this work provides a novel basis for age-dependent structural plasticity in which FSs influence future brain function. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.

  14. Experimental investigation and numerical simulation of plastic flow behavior during forward-backward-radial extrusion process

    Directory of Open Access Journals (Sweden)

    A. Farhoumand

    2016-12-01

    Full Text Available Finite element method was employed to investigate the effect of process parameters of plastic deformation behavior in Forward-Backward-Radial Extrusion (FBRE process. The result of an axisymmetric model shows that the friction between die components and the sample has a substantial effect on the material flow behavior. Although strain heterogeneity index (SHI slightly decreases with an increase in friction, large portion of the sample experiences significant strain heterogeneity. Increasing the friction factor also localizes the strain heterogeneity effect in the backward section, and spread the effect in the forward section. Decreasing the friction in the FBRE process can reduce the amount of the strain heterogeneity in the product while decreases the required punch force substantially. Furthermore, an increase in gap thickness increases the deformation in the area close to the lower punch at the expense of the area in the vicinity of the upper punch. The numerical simulation has a good agreement with the experimental results which confirms the accuracy of the proposed finite element model.

  15. Calibration of "Babyline" RP instruments

    CERN Multimedia

    2015-01-01

      If you have old RP instrumentation of the “Babyline” type, as shown in the photo, please contact the Radiation Protection Group (Joffrey Germa, 73171) to have the instrument checked and calibrated. Thank you. Radiation Protection Group

  16. Validated Stability-Indicating RP-HPLC Method for Simultaneous Determination of Clorsulon and Ivermectin Employing Plackett-Burman Experimental Design for Robustness Testing.

    Science.gov (United States)

    Saad, Ahmed S; Ismail, Nahla S; Soliman, Marwa; Zaazaa, Hala E

    2016-01-01

    A sensitive and highly selective stability-indicating gradient HPLC method was developed and validated for simultaneous determination of clorsulon (CLO) and ivermectin (IVM) in the presence of their degradation products. The drugs were subjected to different stress conditions, including acid and alkaline hydrolysis, oxidative, thermal, and photolytic forced degradation. The robustness of the proposed method was assessed using the Plackett-Burman experimental design, the factors affecting system performance were defined, and nonsignificant intervals for the significant factors were determined. The separation was carried out on a ZORBAX SB phenyl analytical column (250 × 4.6 mm id, 5 μm particle size), with gradient elution utilizing 10 mM sodium dihydrogen phosphate and acetonitrile as mobile phase. UV detection was performed for CLO and IVM at 254 nm over a concentration range of 4-140 and 5-50 μg/mL, respectively, with mean percentage recoveries of 99.90 ± 1.30 and 98.59 ± 1.16%, respectively. The proposed method was successfully applied to a pharmaceutical dosage form containing the investigated drugs. The results were statistically compared with the official HPLC methods, and no significant differences were found.

  17. An experimental study on semi-brittle and plastic rheology of Panzhihua gabbro

    Institute of Scientific and Technical Information of China (English)

    HE; Changrong(何昌荣); ZHOU; Yongsheng(周永胜); SANG; Zunan(桑祖南)

    2003-01-01

    We have carried out a systematic experimental study on semi-brittle and plastic deformation of fine-grained Panzhihua gabbro under dry condition with temperature range of 700-1100℃, confining pressure of 450-500 MPa, and strain rate of 1×10-4-3.1×10-6 s-1, using a triaxial testing system with a Griggs type solid medium pressure vessel. In terms of the parameters in the flow law and microstructure after deformation, the rate-dependent deformation can be categorized into three modes: (i) In temperature range of 700-800℃, the deformation is accommodated by semi-brittle flow, with activation energy Q = 612 ± 12 kJ/mol, and stress exponent n = 14.6. The deformation in microscopic scale corresponds to the dislocation glide accompanied with microfracturing. (ii) In temperature range of 900-950℃, the predominant deformation mechanisms in this phase are mechanical twinning and dislocation glide, with activation energy Q =720 ± 61 kJ/mol, and stress exponent n = 6.4. (iii) In temperature range of 1000-1150℃, the major deformation mechanisms are dislocation glide and dislocation climb with minor processes of partial melting, with activation energy Q = 699 ± 55 kJ/mol and stress exponent n = 4.1. The microstructure and deformation mechanism of our experiments are comparable to the results of clinopyroxene and diabase as observed in previous studies. The flow stress of a mafic lower crust is calculated based on the rheological parameters of dry fine-grained gabbro, which implies that a lower curst with mafic granulite may be brittle, and it is possible to fracture and produce frictional slips. This may be an important implication for earthquake nucleation in the lower crust.

  18. Differential hardening in IF steel - Experimental results and a crystal plasticity based model

    NARCIS (Netherlands)

    Mulder, J.; Eyckens, P.; van den Boogaard, Antonius H.; Hora, P.

    2015-01-01

    Work hardening in metals is commonly described by isotropic hardening, especially for monotonically increasing proportional loading. The relation between different stress states in this case is determined by equivalent stress and strain definitions, based on equal plastic dissipation. However,

  19. Modeling and experimental analyses reveals signaling plasticity in a bi-modular assembly of CD40 receptor activated kinases.

    Directory of Open Access Journals (Sweden)

    Uddipan Sarma

    Full Text Available Depending on the strength of signal dose, CD40 receptor (CD40 controls ERK-1/2 and p38MAPK activation. At low signal dose, ERK-1/2 is maximally phosphorylated but p38MAPK is minimally phosphorylated; as the signal dose increases, ERK-1/2 phosphorylation is reduced whereas p38MAPK phosphorylation is reciprocally enhanced. The mechanism of reciprocal activation of these two MAPKs remains un-elucidated. Here, our computational model, coupled to experimental perturbations, shows that the observed reciprocity is a system-level behavior of an assembly of kinases arranged in two modules. Experimental perturbations with kinase inhibitors suggest that a minimum of two trans-modular negative feedback loops are required to reproduce the experimentally observed reciprocity. The bi-modular architecture of the signaling pathways endows the system with an inherent plasticity which is further expressed in the skewing of the CD40-induced productions of IL-10 and IL-12, the respective anti-inflammatory and pro-inflammatory cytokines. Targeting the plasticity of CD40 signaling significantly reduces Leishmania major infection in a susceptible mouse strain. Thus, for the first time, using CD40 signaling as a model, we show how a bi-modular assembly of kinases imposes reciprocity to a receptor signaling. The findings unravel that the signalling plasticity is inherent to a reciprocal system and that the principle can be used for designing a therapy.

  20. Experimental and computational analysis of micromotions of an uncemented femoral knee implant using elastic and plastic bone material models.

    Science.gov (United States)

    Berahmani, Sanaz; Janssen, Dennis; Verdonschot, Nico

    2017-08-16

    It is essential to calculate micromotions at the bone-implant interface of an uncemented femoral total knee replacement (TKR) using a reliable computational model. In the current study, experimental measurements of micromotions were compared with predicted micromotions by Finite Element Analysis (FEA) using two bone material models: linear elastic and post-yield material behavior, while an actual range of interference fit was simulated. The primary aim was to investigate whether a plasticity model is essential in order to calculate realistic micromotions. Additionally, experimental bone damage at the interface was compared with the FEA simulated range. TKR surgical cuts were applied to five cadaveric femora and micro- and clinical CT- scans of these un-implanted specimens were made to extract geometrical and material properties, respectively. Micromotions at the interface were measured using digital image correlation. Cadaver-specific FEA models were created based on the experimental set-up. The average experimental micromotion of all specimens was 53.1±42.3µm (mean±standard deviation (SD)), which was significantly higher than the micromotions predicted by both models, using either the plastic or elastic material model (26.5±23.9µm and 10.1±10.1µm, respectively; p-valuematerial models). The difference between the two material models was also significant (p-value<0.001). The predicted damage had a magnitude and distribution which was comparable to the experimental bone damage. We conclude that, although the plastic model could not fully predict the micro motions, it is more suitable for pre-clinical assessment of a press-fit TKR implant than using an elastic bone model. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Lubrication of an 85-mm ball bearing with RP-1

    Science.gov (United States)

    Addy, Harold E., Jr.; Schuller, Fredrick T.

    1993-01-01

    A parametric experimental investigation of an 85 millimeter bore angular contact ball bearing running in RP-1 fuel was performed at speeds of 10,000 to 24,000 rpm. Thrust loads were varied from 4450 to 17,800 Newtons (1000 to 4000 lbs.). Radial loads were varied from 1335 to 13,350 Newtons (300 to 3000 lbs.). RP-1 lubrication for the bearing was provided through a stationary jet ring located adjacent to the test bearing outer ring. Increases in both the thrust and radial loads resulted in increased bearing temperature, while increases in shaft speed resulted in much more dramatic increases in bearing temperature. These trends are typical for ball bearings operating under these types of conditions. Results are given for outer ring temperatures of the test bearing at the various test conditions employed. In addition, the heat energy removed from the bearing by the RP-1 was determined by measuring the increase in temperature as the RP-1 passed through the bearing. Results showed that the amount of heat energy removed by the RP-1 increased with both shaft speed and RP-1 flow rate to the bearing.

  2. Numerical Simulation and Experimental Investigation of the Viscoelastic Heating Mechanism in Ultrasonic Plasticizing of Amorphous Polymers for Micro Injection Molding

    Directory of Open Access Journals (Sweden)

    Bingyan Jiang

    2016-05-01

    Full Text Available Ultrasonic plasticizing of polymers for micro-injection molding has been proposed and studied for its unique potential in materials and energy-saving. In our previous work, we have demonstrated the characteristics of the interfacial friction heating mechanism in ultrasonic plasticizing of polymer granulates. In this paper, the other important heating mechanism in ultrasonic plasticizing, i.e., viscoelastic heating for amorphous polymer, was studied by both theoretical modeling and experimentation. The influence mechanism of several parameters, such as the initial temperature of the polymer, the ultrasonic frequency, and the ultrasonic amplitude, was investigated. The results from both numerical simulation and experimentation indicate that the heat generation rate of viscoelastic heating can be significantly influenced by the initial temperature of polymer. The glass transition temperature was found to be a significant shifting point in viscoelastic heating. The heat generation rate is relatively low at the beginning and can have a steep increase after reaching glass transition temperature. In comparison with the ultrasonic frequency, the ultrasonic amplitude has much greater influence on the heat generation rate. In light of the quantitative difference in the viscoelastic heating rate, the limitation of the numerical simulation was discussed in the aspect of the assumptions and the applied mathematical models.

  3. Exercise in Experimental Plastics Technology: Hot Embossing of Polymers with surface microstructure

    DEFF Research Database (Denmark)

    Eriksson, Torbjörn Gerhard; Rasmussen, Henrik Koblitz

    2004-01-01

    such as relatively low cost for embossing tools, simple operation and high replication accuracy for small features. Two different plastic materials will be used to replicate surface microstructures by hot embossing. The hot embossing will be done in a hydraulic press where it is easy to control temperature...

  4. Experimental investigation and numerical simulation of plastic flow behavior during forward-backward-radial extrusion process

    OpenAIRE

    A. Farhoumand; R. Ebrahimi

    2016-01-01

    Finite element method was employed to investigate the effect of process parameters of plastic deformation behavior in Forward-Backward-Radial Extrusion (FBRE) process. The result of an axisymmetric model shows that the friction between die components and the sample has a substantial effect on the material flow behavior. Although strain heterogeneity index (SHI) slightly decreases with an increase in friction, large portion of the sample experiences significant strain heterogeneity. Increasing...

  5. An experimental study on thermo-catalytic pyrolysis of plastic waste using a continuous pyrolyser.

    Science.gov (United States)

    Auxilio, Anthony R; Choo, Wei-Lit; Kohli, Isha; Chakravartula Srivatsa, Srikanth; Bhattacharya, Sankar

    2017-09-01

    A bench scale, two-stage, thermo-catalytic reactor equipped with a continuous feeding system was used to pyrolyse pure and waste plastics. Experiments using five zeolitic and clay-based catalysts of different forms (pellet and powders) and different plastic feedstocks - virgin HDPE, HDPE w1aste and mixed plastic waste (MPW) were compared to the control experiments - pyrolysis without catalyst. Results indicated that the two pelletized catalysts were the most promising for the conditions employed. Of these two, one with higher acidity and surface area was highly selective for the gasoline fraction (C5-C11) giving 80% from the total medium distillate conversion using virgin HDPE as feedstock. It also produced the least amount of olefins (17% for virgin HDPE, 4% for HDPE waste and 2% for MPW) and coke (pelletized catalyst exhibited high selectivity for the diesel fraction (C12-C25) giving 63% from the total medium distillate conversion using virgin HDPE as feedstock. The amount of coke deposited on the catalyst surface depended mainly on the mesopore volume, with less coke deposited as the mesopore volume increased. The variation in catalyst selectivity with acidity strength due to Lewis sites on the catalyst surface controls selectivity towards carbon chain length. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. An ESPI experimental study on the phenomenon of fracture in glass. Is it brittle or plastic?

    Science.gov (United States)

    Ferretti, Daniele; Rossi, Marco; Royer-Carfagni, Gianni

    2011-07-01

    The crack opening displacement (COD) in annealed soda-lime (float) glass has been measured with an electronic speckle pattern interferometry (ESPI) apparatus using coherent laser light. Specimens, naturally pre-cracked with a particular technique, were loaded under strain-driven bending until crack propagated; at regular intervals loading was paused to let the crack reach subcritical equilibrium and the COD measured. By using a post-processing algorithm comparing four images lighted with phase-shifted laser beams, surface displacements could be measured at a resolution of 0.01 μm. Glass transparency has allowed to see through that the propagating crack front is not sharp but curved, jagged and merged in an opaque neighborhood. Numerical simulations show that the measured CODs cannot be reproduced if cohesive surface forces à la Barenblatt-Dugdale bridge the crack lips; instead a plastic-like region must form in a bulk neighborhood of the tip, where inelastic strains are associated with volume increase rather than deviatoric distortion. For this, a Gurson-Tvergaard model of porous plasticity, accounting for the formation of microvoids/microcracks, has been found more efficient than classical von Mises plasticity. This study confirms the formation at the crack tip of a process zone, whose occurrence in brittle materials like glass is still a subject of controversy.

  7. EXPERIMENTAL EVALUATION OF A DIESEL ENGINE WITH BLENDS OF DIESEL-PLASTIC PYROLYSIS OIL

    Directory of Open Access Journals (Sweden)

    Mr. Rajesh Guntur,

    2011-06-01

    Full Text Available Environmental degradation and depletion of oil reserves are matters of great concern around the globe. Developing countries like India depend heavily on crude oil import of about 125 Mt per annum (7:1diesel/gasoline. Diesel being the main transportation fuel in India, finding a suitable fuel alternative to diesel is an urgent need. In this context, pyrolysis of waste plastic solid is currently receiving renewed interest. Waste plastic pyrolysis oil is suitable for compression ignition engines and more attention is focused in India because of its potential to generate large-scale employment and relatively low environmental degradation. In the present work the performance and emission characteristics of a single cylinder, constant speed, and direct injection diesel engine using waste plastic pyrolysis oil blends as an alternate fuel were evaluated and the results are compared with the standard diesel fuel operation. Results indicated that the brake thermal efficiency was highercompared to diesel at part load condition. Carbon monoxide, Carbon dioxide and hydrocarbon emissions were higher and oxygen emission was lower compared to diesel operation.

  8. EXPERIMENTAL STUDY ON PLASTICITY OF PROLIFERATED NEURAL STEM CELLS IN ADULT RATS AFTER CEREBRAL INFARCTION

    Institute of Scientific and Technical Information of China (English)

    Bo Zhang; Ren-zhi Wang; Zhi-gang Lian; Yang Song; Yong Yao

    2006-01-01

    Objective To investigate whether there is endogenous neural stem cell proliferation and whether these proliferated neural stem cells represent neural plasticity in the adult rats after cerebral infarction.Methods Cerebral infarction models of rats were established and the dynamic expression of bromodeoxyuridine (BrdU), BrdU/polysialylated neural cell adhesion molecule (PSA-NCAM) were determined by immunohistochemistry and immunofluorescence staining. BrdU was used to mark dividing neural stem cells. PSA-NCAM was used to mark the plasticity of neural stem cells.Results Compared with controls, the number of BrdU-positive cells in the subventricular zone (SVZ) and hippocampus increased significantly at 1st day after cerebral infarction (P<0.05), reached maximum at 7th day, decreased markedly at 14th day, but it was still elevated compared with that of the controls (P<0.05). The number of BrdU-labeled with PSA-NCAM-positive cells increased significantly at 7th day (P<0.05 ), reached maximum at 14th day,markedly decreased at 28th day, but it was still elevated compared with that of the controls (P<0.05). It was equal to 60% of the number of BrdU-positive cells in the same period.Conclusion Cerebral infarction may stimulate the proliferation of endogenous neural stem cells in situ and most proliferated neural stem cells represent neural plasticity.

  9. Experimental Validation of Two-dimensional Finite Element Method for Simulating Constitutive Response of Polycrystals During High Temperature Plastic Deformation

    Science.gov (United States)

    Agarwal, Sumit; Briant, Clyde L.; Krajewski, Paul E.; Bower, Allan F.; Taleff, Eric M.

    2007-04-01

    A finite element method was recently designed to model the mechanisms that cause superplastic deformation (A.F. Bower and E. Wininger, A Two-Dimensional Finite Element Method for Simulating the Constitutive Response and Microstructure of Polycrystals during High-Temperature Plastic Deformation, J. Mech. Phys. Solids, 2004, 52, p 1289-1317). The computations idealize the solid as a collection of two-dimensional grains, separated by sharp grain boundaries. The grains may deform plastically by thermally activated dislocation motion, which is modeled using a conventional crystal plasticity law. The solid may also deform by sliding on the grain boundaries, or by stress-driven diffusion of atoms along grain boundaries. The governing equations are solved using a finite element method, which includes a front-tracking procedure to monitor the evolution of the grain boundaries and surfaces in the solid. The goal of this article is to validate these computations by systematically comparing numerical predictions to experimental measurements of the elevated-temperature response of aluminum alloy AA5083 (M.-A. Kulas, W.P. Green, E.M. Taleff, P.E. Krajewski, and T.R. McNelley, Deformation Mechanisms in Superplastic AA5083 materials. Metall. Mater. Trans. A, 2005, 36(5), p 1249-1261). The experimental work revealed that a transition occurs from grain-boundary sliding to dislocation (solute-drag) creep at approximately 0.001/s for temperatures between 425 and 500 °C. In addition, increasing the grain size from 7 to 10 μm decreased the transition to significantly lower strain rates. Predictions from the finite element method accurately predict the effect of grain size on the transition in deformation mechanisms.

  10. Experimental Study on Elastic-Plastic Behavior of SRC Columns with High Strength Steel

    OpenAIRE

    2006-01-01

    The demand to use high strength and high performance material because of large span and high rise of building in recent years. As to use of high-strength steel in composite steel and reinforced concrete structures, it remains to be clarified whether the ductile behavior can be ensured, especially when the high-strength steel is used in combination with High-strength concrete. This paper describes the test results on the elasto-plastic behavior of SRC column using high strength steel, and disc...

  11. Experimental and numerical analyses of pure copper during ECFE process as a novel severe plastic deformation method

    Directory of Open Access Journals (Sweden)

    M. Ebrahimi

    2014-02-01

    Full Text Available In this paper, a new severe plastic deformation method called equal channel forward extrusion (ECFE process has been proposed and investigated by experimental and numerical approaches on the commercial pure copper billets. The experimental results indicated that the magnitudes of yield strength, ultimate tensile strength and Vickers micro-hardness have been markedly improved from 114 MPa, 204 MPa and 68 HV as the annealed condition to 269 MPa, 285 MPa and 126 HV after the fourth pass of ECFE process, respectively. In addition, scanning electron microscopy observation of the samples showed that the average grain size of the as-received state which is about 22 μm has been reduced to 1.4 μm after the final pass. The numerical investigation suggested that although one pass ECFE process fabricates material with the mean effective strain magnitude of about 1, the level of imposed effective plastic strain gradually diminishes from the circumference to the center of the deformed billet.

  12. Experimental characterizations of non-seizing solutions for plastic moulding tools

    Energy Technology Data Exchange (ETDEWEB)

    Jacquet, P., E-mail: philippe.jacquet@ecam.fr [Laboratoire de Sciences des Materiaux, ECAM Lyon, 40 Montee Saint Barthelemy, Universite de Lyon, 69 321 Lyon Cedex (France); LaBoMaP, Arts and Metiers ParisTech, Centre de Cluny, Rue porte de Paris, 71 250 Cluny (France); Golabczak, M. [Department of Production Engineering, Faculty of Mechanical Engineering, Technical University of Lodz (Poland); Lourdin, P. [Laboratoire de Sciences des Materiaux, ECAM Lyon, 40 Montee Saint Barthelemy, Universite de Lyon, 69 321 Lyon Cedex (France)

    2012-11-15

    Highlights: Black-Right-Pointing-Pointer Struggle against tools' wear in the plastics moulding industry. Black-Right-Pointing-Pointer Comparison between nitriding solutions and PVD coating. Black-Right-Pointing-Pointer 2 solutions show an excellent behaviour: WC/C coating and salt bath nitriding followed by post-oxidation. - Abstract: In the plastics moulding industry many parts sustain movement in relation to other pieces: ejectors, slides, dies, etc. Some seizing or micro-welding may appear, especially when lubrication is not used. For many years, different kinds of hard coatings were developed to avoid such problems. In this paper, the investigation analyses these problems related with nitride layers which were obtained thanks to four different processes: salt bath nitriding, salt bath nitriding followed by a post-oxidation, gaseous low pressure nitriding and plasma nitriding. Several properties of the layers were investigated such as hardness, microstructure and constitution of the surface by means of X-ray diffraction (XRD), roughness, and friction coefficient at both room temperature and 100 Degree-Sign C. Some important differences were pointed out between the different layers. The solution provided by a salt bath nitriding followed with an oxidation sequence gave, in terms of tribology, as good results as a physical vapour deposition (PVD) WC-C coating which was used as a reference for this study.

  13. Npas4 Expression in Two Experimental Models of the Barrel Cortex Plasticity

    Directory of Open Access Journals (Sweden)

    Aleksandra Kaliszewska

    2015-01-01

    Full Text Available Npas4 has recently been identified as an important factor in brain plasticity, particularly in mechanisms of inhibitory control. Little is known about Npas4 expression in terms of cortical plasticity. In the present study expressions of Npas4 and the archetypal immediate early gene (IEG c-Fos were investigated in the barrel cortex of mice after sensory deprivation (sparing one row of whiskers for 7 days or sensory conditioning (pairing stimulation of one row of whiskers with aversive stimulus. Laser microdissection of individual barrel rows allowed for analysis of IEGs expression precisely in deprived and nondeprived barrels (in deprivation study or stimulated and nonstimulated barrels (in conditioning study. Cortex activation by sensory conditioning was found to upregulate the expression of both Npas4 and c-Fos. Reorganization of cortical circuits triggered by removal of selected rows of whiskers strongly affected c-Fos but not Npas4 expression. We hypothesize that increased inhibitory synaptogenesis observed previously after conditioning may be mediated by Npas4 expression.

  14. Plasticity in leaf-level water relations of tropical rainforest trees in response to experimental drought.

    Science.gov (United States)

    Binks, Oliver; Meir, Patrick; Rowland, Lucy; da Costa, Antonio Carlos Lola; Vasconcelos, Steel Silva; de Oliveira, Alex Antonio Ribeiro; Ferreira, Leandro; Christoffersen, Bradley; Nardini, Andrea; Mencuccini, Maurizio

    2016-07-01

    The tropics are predicted to become warmer and drier, and understanding the sensitivity of tree species to drought is important for characterizing the risk to forests of climate change. This study makes use of a long-term drought experiment in the Amazon rainforest to evaluate the role of leaf-level water relations, leaf anatomy and their plasticity in response to drought in six tree genera. The variables (osmotic potential at full turgor, turgor loss point, capacitance, elastic modulus, relative water content and saturated water content) were compared between seasons and between plots (control and through-fall exclusion) enabling a comparison between short- and long-term plasticity in traits. Leaf anatomical traits were correlated with water relation parameters to determine whether water relations differed among tissues. The key findings were: osmotic adjustment occurred in response to the long-term drought treatment; species resistant to drought stress showed less osmotic adjustment than drought-sensitive species; and water relation traits were correlated with tissue properties, especially the thickness of the abaxial epidermis and the spongy mesophyll. These findings demonstrate that cell-level water relation traits can acclimate to long-term water stress, and highlight the limitations of extrapolating the results of short-term studies to temporal scales associated with climate change.

  15. Experimental study of Electro-Plastic Effect on Advanced High Strength Steels

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Xun; Lan, Shuhuai; Ni, Jun, E-mail: junni@umich.edu

    2013-10-10

    Application of Advanced High Strength Steels (AHSS) into vehicle structures calls for innovative manufacturing processes. In terms of reducing deformation resistance through external energy, Electro-Plastic Effect (EPE) provides a potential alternative to traditional thermal softening phenomenon. In this work, effectiveness of EPE on one group of AHSS, Transformation Induced Plasticity (TRIP) Steel, was evaluated. It was found that EPE cannot be effectively initiated until the current density reaches a threshold value between 7.4 A/mm{sup 2} and 11.4 A/mm{sup 2}. Besides, the softening phenomenon is more distinct at larger strains. Underlying mechanisms are explained from perspectives of dislocation multiplication, gliding and mechanical twinning. The inevitable Joule heating phenomenon associated with current was suppressed with forced air cooling and the temperature distribution inside the tensile specimen was numerically calculated with a coupled Finite Element Model. Effectiveness of EPE rather than thermal softening or expansion was further proved with the larger flow stress reduction under higher current density and shorter pulses at same temperature increase. Hollomon equation was adopted to model the observed stress strain relationships. Since material properties of TRIP steels are directly related to the phase transformation from retained austenite into martensite, volume fraction of retained austenite was quantitatively measured by X-ray Diffraction (XRD). It was found that the applied current retarded martensitic transformation process. Metallographic analysis was further performed and phenomena of change of grain structures and phase distribution were hardly observable.

  16. Complement peptide C3a stimulates neural plasticity after experimental brain ischaemia.

    Science.gov (United States)

    Stokowska, Anna; Atkins, Alison L; Morán, Javier; Pekny, Tulen; Bulmer, Linda; Pascoe, Michaela C; Barnum, Scott R; Wetsel, Rick A; Nilsson, Jonas A; Dragunow, Mike; Pekna, Marcela

    2017-02-01

    Ischaemic stroke induces endogenous repair processes that include proliferation and differentiation of neural stem cells and extensive rewiring of the remaining neural connections, yet about 50% of stroke survivors live with severe long-term disability. There is an unmet need for drug therapies to improve recovery by promoting brain plasticity in the subacute to chronic phase after ischaemic stroke. We previously showed that complement-derived peptide C3a regulates neural progenitor cell migration and differentiation in vitro and that C3a receptor signalling stimulates neurogenesis in unchallenged adult mice. To determine the role of C3a-C3a receptor signalling in ischaemia-induced neural plasticity, we subjected C3a receptor-deficient mice, GFAP-C3a transgenic mice expressing biologically active C3a in the central nervous system, and their respective wild-type controls to photothrombotic stroke. We found that C3a overexpression increased, whereas C3a receptor deficiency decreased post-stroke expression of GAP43 (P brain injury. © The Author (2016). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  17. Experimental study on the friction effect of plastic stents for biliary stone fragmentation (with video).

    Science.gov (United States)

    Kwon, Chang-Il; Kim, Gwangil; Jeong, Seok; Choi, Sung Hoon; Ko, Kwang Hyun; Lee, Don Haeng; Cho, Joo Young; Hong, Sung Pyo

    2017-06-16

    In patients with irretrievable or intractable bile duct stone, temporary insertion of a plastic stent (PS) followed by further endoscopic retrograde cholangiopancreatography (ERCP) or surgery has been recommended as a 'bridge' therapy. However, the exact mechanism of stone fragmentation has not been discovered. The aim of the present study was to evaluate whether PS shape can facilitate stone fragmentation. Using a new in vitro bile flow phantom model, we compared the friction effect among three different PS groups (straight PS group, double pigtail-shaped PS group, and screw-shaped PS group) and a control group. Each group had 10 silicon tube blocks that separately contained one stone and two PS. The control group had 10 blocks each with only a stone and no PS. We carried out analysis of the friction effect by stone weight and volume changes among the groups, excluding fragmented stones. After 8 weeks, complete fragmentation was noted in one out of 34 cholesterol stones (2.9%) and in four out of six pigmented stones (66.7%). Fragmentation tended to be more prominent in the screw-shaped PS group than in the straight PS group, double pigtail-shaped group, and control group (volume change: -11.33%, 7.94%, 4.43%, and 2.05%, respectively, P = 0.1390; weight change: -9.30%, 0.71%, -0.10%, and -1.23%, respectively, P = 0.3553). Stone fragmentation may be induced by PS friction effect. Also, screw-shaped plastic stents may improve friction effect. These results may help guide future PS development and clinical decisions. © 2017 Japan Gastroenterological Endoscopy Society.

  18. Axure RP 6 Prototyping Essentials

    CERN Document Server

    Schwartz, Ezra

    2012-01-01

    Axure RP 6 Prototyping Essentials is a detailed, practical primer on the leading rapid prototyping tool. Short on jargon and high on concepts, real-life scenarios and step-by-step guidance through hands-on examples, this book will show you how to integrate Axure into your UX workflow. This book is written for UX practitioners, business analysts, product managers, and anyone else who is involved in UX projects. The book assumes that you have no or very little familiarity with Axure. It will help you if you are evaluating the tool for an upcoming project or are required to quickly get up to spee

  19. High Morphologic Plasticity of Microglia/Macrophages Following Experimental Intracerebral Hemorrhage in Rats

    Directory of Open Access Journals (Sweden)

    Shu-Sheng Yang

    2016-07-01

    Full Text Available As current efforts have limited effects on the clinical outcome of intracerebral hemorrhage (ICH, the mechanisms including microglia/macrophages that involved inflammation need further investigation. Here, 0.4 units of collagenase VII were injected into the left caudate putamen (CPu to duplicate ICH rat models. In the brains of ICH rats, microglia/macrophages, the nearest cells to the hemorrhagic center, were observed as ameboid and Prussian-blue positive. Furthermore, the ameboid microglia/macrophages were differentiation (CD 68 and interleukin-1β (IL-1β positive, and neither CD206 nor chitinase3-like 3 (Ym1 positive, suggesting their strong abilities of phagocytosis and secretion of IL-1β. According to the distance to the hemorrhagic center, we selected four areas—I, II, III, and IV—to analyze the morphology of microglia/macrophages. The processes decreased successively from region I to region IV. Microglia/macrophages in region IV had no processes. The processes in region I were radially distributed, however, they showed obvious directivity towards the hemorrhagic center in regions II and III. Region III had the largest density of compactly arrayed microglia/macrophages. All these in vivo results present the high morphologic plasticity of microglia/macrophages and their functions in the pathogenesis of ICHs.

  20. Analytical and Experimental Investigation of Process Loads on Incremental Severe Plastic Deformation

    Science.gov (United States)

    Okan Görtan, Mehmet

    2017-05-01

    From the processing point of view, friction is a major problem in the severe plastic deformation (SPD) using equal channel angular pressing (ECAP) process. Incremental ECAP can be used in order to optimize frictional effects during SPD. A new incremental ECAP has been proposed recently. This new process called as equal channel angular swaging (ECAS) combines the conventional ECAP and the incremental bulk metal forming method rotary swaging. ECAS tool system consists of two dies with an angled channel that contains two shear zones. During ECAS process, two forming tool halves, which are concentrically arranged around the workpiece, perform high frequency radial movements with short strokes, while samples are pushed through these. The oscillation direction nearly coincides with the shearing direction in the workpiece. The most important advantages in comparison to conventional ECAP are a significant reduction in the forces in material feeding direction plus the potential to be extended to continuous processing. In the current study, the mechanics of the ECAS process is investigated using slip line field approach. An analytical model is developed to predict process loads. The proposed model is validated using experiments and FE simulations.

  1. Optics of carbon fiber-reinforced plastics - A theoretical and an experimental study

    Science.gov (United States)

    Hohmann, Ansgar; ElMaklizi, Ahmed; Foschum, Florian; Voit, Florian; Bergmann, Florian; Simon, Emanuel; Reitzle, Dominik; Kienle, Alwin

    2016-09-01

    Laser processing of carbon fiber-reinforced plastics (CFRP) as well as their design optimization are strongly emerging fields. As the optics of CFRP is still rather unknown, the optical behavior of CFRP was investigated in this study. Different simulation models were implemented to simulate reflectance from CFRP samples as well as distribution and absorption of light within these samples. The methods include an analytical solution of Maxwell's equations and Monte Carlo solutions of the radiative transfer theory. We show that strong inaccurracies occur, if light propagation in CFRP is modeled using the radiative transfer theory. Therefore, the solution of Maxwell's equations is the method of choice for calculation of light propagation in CFRP. Furthermore, measurements of the reflectance of light from CFRP were performed and compared to the simulations for investigation of the optical behavior. Information on the refractive index of carbon fibers was obtained via goniometric measurements. The amount of reflected light was determined as 6.05±0.38% for light polarized parallel to the fiber direction, while it was 3.65±0.41% for light polarized perpendicular to the fiber direction in case of laser-processed CFRP.

  2. Quantitative evaluation of tissue reconfigurations after the plastic reconstruction of experimental defect of the anterior abdominal wall in rats.

    Directory of Open Access Journals (Sweden)

    Malkov I.I.

    2007-01-01

    Full Text Available The active retrieval of methods for the increase of the efficiency of ventral hernia alloplasty is performed now; however the structural-functional changes of scar and muscle tissues during their reorganization are still little studied. The analysis of relationship of connective tissue with the hemomicrocirculation elements plays the important role for the understanding of the structural-functional condition of the anterior abdominal wall and also concrete mechanisms of reorganization of microvessels taking into account the dynamics of muscle-aponeurotic structures reconfiguration. The purpose of the current study was to determine the dynamics of structural-functional reconfiguration of microcircular and muscle-aponeurotic components, as well as connective tissue in the anterior abdominal wall after alloplasty of experimental ventral defect with the polypropylene monofilament net "Prolene". The quantitative morphological analysis was carried out during 1 year. The analysis of scar tissue formation and muscles reconfiguration in the anterior abdominal wall after plastic reconstruction of experimental defect allowed to reveal that the presence of polypropylene prosthetic device increases the duration of early inflammatory processes in a moderate degree, providing, however, adequate and full structural reconfiguration of scar and muscle tissue in the future, including microcirculation components.

  3. Measuring the Biodegradability of Plastic Polymers in Olive-Mill Waste Compost with an Experimental Apparatus

    Directory of Open Access Journals (Sweden)

    Francesco Castellani

    2016-01-01

    Full Text Available The use of biodegradable polymers is spreading in agriculture to replace those materials derived from petroleum, thus reducing the environmental concerns. However, to issue a significant assessment, biodegradation rate must be measured in case-specific standardized conditions. In accordance with ISO 14855-1, we designed and used an experimental apparatus to evaluate the biodegradation rate of three biopolymers based on renewable resources, two poly(ε-caprolactone (PCL composites, and a compatibilized polylactic acid and polybutyrate (PLA/PBAT blend. Biodegradation tests were carried out under composting condition using mature olive-mill waste (OMW compost as inoculum. Carbon dioxide emissions were automatically recorded by infrared gas detectors and also trapped in saturated Ba(OH2 solution and evaluated via a standard titration method to check the results. Some of the samples reached more than 80% biodegradation in less than 20 days. Both the experimental apparatus and the OMW compost showed to be suitable for the cases studied.

  4. Radiation Protection Section (SC/SL/RP)

    CERN Multimedia

    2006-01-01

    We should like to inform you that the Radiation Protection Section (SC/SL/RP) located on the Prévessin site has moved from Building 865 (ground floor) to new premises in Wing A of Building 892 (second floor). Telephone numbers remain the same. SC/SL/RP section

  5. Experimental investigation of fibre reinforced plastics with hybrid layups under high-velocity impact loads

    Directory of Open Access Journals (Sweden)

    Marco Romano

    2014-07-01

    Full Text Available This paper deals with experimental investigations concerning energy dissipation capacity of different kinds of reinforcement fibres in monolithic and hybrid layups under high-velocity impact loads. The investigated kinds of fibres are carbon, glass and basalt fibres. Therefore test panels, using the same thermoset resin, were built up and cured by autoclave processing. The fibre volume content of the test panels has been determined. Furthermore the influence of a separating layer at selected positions in the hybrid stacked panels was investigated. The results show the influence and the energy dissipation capacity of each single kind of fibre and the enhanced properties for the hybrid layups by hybrid stacking sequences and the use of a separating core material.

  6. Experimental Investigations into Abrasive Waterjet Machining of Carbon Fiber Reinforced Plastic

    Directory of Open Access Journals (Sweden)

    Prasad D. Unde

    2015-01-01

    Full Text Available Abrasive waterjet machining (AWJM is an emerging machining process in which the material removal takes place due to abrasion. A stream of abrasive particles mixed with filtered water is subjected to the work surface with high velocity. The present study is focused on the experimental research and evaluation of the abrasive waterjet machining process in order to evaluate the technological factors affecting the machining quality of CFRP laminate using response surface methodology. The standoff distance, feed rate, and jet pressure were found to affect kerf taper, delamination, material removal rate, and surface roughness. The material related parameter, orientation of fiber, has been also found to affect the machining performance. The kerf taper was found to be 0.029 for 45° fiber orientation whereas it was 0.036 and 0.038 for 60° and 90°, respectively. The material removal rate is 18.95 mm3/sec for 45° fiber orientation compared to 18.26 mm3/sec for 60° and 17.4 mm3/sec for 90° fiber orientation. The Ra value for 45° fiber orientation is 4.911 µm and for 60° and 90° fiber orientation it is 4.927 µm and 4.974 µm, respectively. Delamination factor is found to be more for 45° fiber orientation, that is, 2.238, but for 60° and 90° it is 2.029 and 2.196, respectively.

  7. An experimental study on usage of plastic oil and B20 algae biodiesel blend as substitute fuel to diesel engine.

    Science.gov (United States)

    Ramesha, D K; Kumara, G Prema; Lalsaheb; Mohammed, Aamir V T; Mohammad, Haseeb A; Kasma, Mufteeb Ain

    2016-05-01

    Usage of plastics has been ever increasing and now poses a tremendous threat to the environment. Millions of tons of plastics are produced annually worldwide, and the waste products have become a common feature at overflowing bins and landfills. The process of converting waste plastic into value-added fuels finds a feasible solution for recycling of plastics. Thus, two universal problems such as problems of waste plastic management and problems of fuel shortage are being tackled simultaneously. Converting waste plastics into fuel holds great promise for both the environmental and economic scenarios. In order to carry out the study on plastic wastes, the pyrolysis process was used. Pyrolysis runs without oxygen and in high temperature of about 250-300 °C. The fuel obtained from plastics is blended with B20 algae oil, which is a biodiesel obtained from microalgae. For conducting the various experiments, a 10-HP single-cylinder four-stroke direct-injection water-cooled diesel engine is employed. The engine is made to run at 1500 rpm and the load is varied gradually from 0 to 100 %. The performance, emission and combustion characteristics are observed. The BTE was observed to be higher with respect to diesel for plastic-biodiesel blend and biodiesel blend by 15.7 and 12.9 %, respectively, at full load. For plastic-biodiesel blend, the emission of UBHC and CO decreases with a slight increase in NO x as compared to diesel. It reveals that fuel properties are comparable with petroleum products. Also, the process of converting plastic waste to fuel has now turned the problems into an opportunity to make wealth from waste.

  8. Computational modeling and experimental studies of the dynamic performance of ultrasonic horn profiles used in plastic welding.

    Science.gov (United States)

    Roopa Rani, M; Rudramoorthy, R

    2013-03-01

    Ultrasonic horns are tuned components designed to vibrate in a longitudinal mode at ultrasonic frequencies. Reliable performance of such horns is normally decided by the uniformity of vibration amplitude at the working surface and the stress developed during loading condition. The horn design engineer must pay particular attention to designing a tool that will produce the desired amplitude without fracturing. The present work discusses horn configurations which satisfy these criteria and investigates the design requirements of horns in ultrasonic system. Different horn profiles for ultrasonic welding of thermoplastics have been characterized in terms of displacement amplitude and von-Mises stresses using modal and harmonic analysis. To validate the simulated results, five different horns are fabricated from Aluminum, tested and tuned to the operating frequency. Standard ABS plastic parts are welded using these horns. Temperature developed during the welding of ABS test parts using different horns is recorded using sensors and National Instruments (NIs) data acquisition system. The recorded values are compared with the predicted values. Experimental results show that welding using a Bezier horn has a high interface temperature and the welded joints had higher strength as compared to the other horn profiles.

  9. The temperate phages RP2 and RP3 of Streptomyces rimosus.

    Science.gov (United States)

    Rausch, H; Vesligaj, M; Pocta, D; Biuković, G; Pigac, J; Cullum, J; Schmieger, H; Hranueli, D

    1993-10-01

    The oxytetracycline-producing Streptomyces rimosus strains R6-65 and R7 (ATCC 10970) are lysogenic for the two narrow-host-range phages RP2 and RP3. Both phages are released at low frequency from the lysogenic strains and form plaques on 'cured' S. rimosus strains. RP2 and RP3 are of similar shape with flexible tails and contain double-stranded DNA of about 70% G+C with cohesive ends (group B1 of bacteriophage classification). The two phages also have identical, very slow, growth kinetics in S. rimosus, with a latent phase of about 6 h and a rise period of about 4 h. RP2 and RP3 are heteroimmune and they differ slightly in their size of phage particles and length of DNA (64.7 and 62.4 kb for RP2 and RP3, respectively). The restriction maps of the two phages are completely different, and hybridization experiments showed only one short region of sequence similarity (less than 430 bp); the two phages are thus essentially unrelated. Both phages lysogenize their hosts by recombination via defined attachment (att) sites. The positions of the attP sites have been localized on the restriction maps of RP2 and RP3 to restriction fragments of 800 and 300 bp, respectively. The prophages did not affect the level of oxytetracycline production or the genetic instability of this trait.

  10. Theoretical Analysis and Experimental Study on the Coating Removal from Passenger-Vehicle Plastics for Recycling by Using Water Jet Technology

    Science.gov (United States)

    Zhang, Hongshen; Chen, Ming

    2015-11-01

    The recovery and utilization of automotive plastics are a global concern because of the increasing number of end-of-life vehicles. In-depth studies on technologies for the removal of coatings from automotive plastics can contribute to the high value-added levels of the recycling and utilization of automotive plastic. The liquid waste generated by removing chemical paint by using traditional methods is difficult to handle and readily produces secondary pollution. Therefore, new, clean, and highly efficient techniques of paint removal must be developed. In this article, a method of coating removal from passenger-vehicle plastics was generated based on high-pressure water jet technology to facilitate the recycling of these plastics. The established technology was theoretically analyzed, numerically simulated, and experimentally studied. The high-pressure water jet equipment for the removal of automotive-plastic coatings was constructed through research and testing, and the detailed experiments on coating removal rate were performed by using this equipment. The results showed that high-pressure water jet technology can effectively remove coatings on the surfaces of passenger-vehicle plastics. The research also revealed that the coating removal rate increased as jet pressure ( P) increased and then decreased when jet moving speed ( Vn) increased. The rate decreased as the distance from nozzle to work piece ( S nw ) and the nozzle angle ( Φ) increased. The mathematical model for the rate of removal of coatings from bumper surfaces by water jet was derived based on the experiment data and can effectively predict coating removal rate under different operating conditions.

  11. Inbreeding and adaptive plasticity: an experimental analysis on predator-induced responses in the water flea Daphnia.

    Science.gov (United States)

    Swillen, Ine; Vanoverbeke, Joost; De Meester, Luc

    2015-07-01

    Several studies have emphasized that inbreeding depression (ID) is enhanced under stressful conditions. Additionally, one might imagine a loss of adaptively plastic responses which may further contribute to a reduction in fitness under environmental stress. Here, we quantified ID in inbred families of the cyclical parthenogen Daphnia magna in the absence and presence of fish predation risk. We test whether predator stress affects the degree of ID and if inbred families have a reduced capacity to respond to predator stress by adaptive phenotypic plasticity. We obtained two inbred families through clonal selfing within clones isolated from a fish pond. After mild purging under standardized conditions, we compared life history traits and adaptive plasticity between inbred and outbred lineages (directly hatched from the natural dormant egg bank of the same pond). Initial purging of lineages under standardized conditions differed among inbred families and exceeded that in outbreds. The least purged inbred family exhibited strong ID for most life history traits. Predator-induced stress hardly affected the severity of ID, but the degree to which the capacity for adaptive phenotypic plasticity was retained varied strongly among the inbred families. The least purged family overall lacked the capacity for adaptive phenotypic plasticity, whereas the family that suffered only mild purging exhibited a potential for adaptive plasticity that was comparable to the outbred population. We thus found that inbred offspring may retain the capacity to respond to the presence of fish by adaptive phenotypic plasticity, but this strongly depends on the parental clone engaging in selfing.

  12. Sorting Plastic Waste in Hydrocyclone

    Directory of Open Access Journals (Sweden)

    Ernestas Šutinys

    2011-02-01

    Full Text Available The article presents material about sorting plastic waste in hydrocyclone. The tests on sorting plastic waste were carried out. Also, the findings received from the performed experiment on the technology of sorting plastic waste are interpreted applying an experimental model of the equipment used for sorting plastics of different density.Article in Lithuanian

  13. Plastic Surgery

    Science.gov (United States)

    ... Surgery? A Week of Healthy Breakfasts Shyness Plastic Surgery KidsHealth > For Teens > Plastic Surgery Print A A ... forehead lightened with a laser? What Is Plastic Surgery? Just because the name includes the word "plastic" ...

  14. An Experimental Investigation on Utilization of Waste Plastic as a Modifier in Rigid Pavements for Improving Strength

    Directory of Open Access Journals (Sweden)

    M.Chandu

    2016-12-01

    Full Text Available The percent study investigates the effective use of waste plastic as a modifier for cement concrete roads. Civilization produces waste products disposals issue of the waste products is a challenge. Solid waste management is the thrust area. The various waste materials, plastic waste and principle solid waste are of great concern these leads to disposal crisis and environmental pollution. On the other side, road traffic is increasing. The load bearing capacity of the roads are to be increased. Our present work is helping to take care of both these aspects. Plastic waste consists of carry bags cups and disposals. Plastic waste which is cleaned is cut into a size such that it passes through 2.3mm sieve using shredding machine. The aggregates mix is heated and the plastic is coated over aggregates and this coated stones can be used for road constructing. By this process a road of 1km length 3.375m width of single lane can consumes 10,00000 carry bags and road strength is increased and found no pot holes. Commonly soil, aggregates, sand, cement can be used in road construction. Natural materials being exhaustible in nature, its quantity is declining gradually. If our material can be utilized in highway construction, the pollution and disposal problems may be partly reduced. The use of the innovative technology will not only strengthen the road construction but also increase the road life as well as will help to improve the environment. In my research work I have done a thorough study on the methodology of using plastic waste coat over aggregates and presented various tests performed on aggregates.

  15. Expression of wild-type Rp1 protein in Rp1 knock-in mice rescues the retinal degeneration phenotype.

    Directory of Open Access Journals (Sweden)

    Qin Liu

    Full Text Available Mutations in the retinitis pigmentosa 1 (RP1 gene are a common cause of autosomal dominant retinitis pigmentosa (adRP, and have also been found to cause autosomal recessive RP (arRP in a few families. The 33 dominant mutations and 6 recessive RP1 mutations identified to date are all nonsense or frameshift mutations, and almost exclusively (38 out of 39 are located in the 4(th and final exon of RP1. To better understand the underlying disease mechanisms of and help develop therapeutic strategies for RP1 disease, we performed a series of human genetic and animal studies using gene targeted and transgenic mice. Here we report that a frameshift mutation in the 3(rd exon of RP1 (c.686delC; p.P229QfsX35 found in a patient with recessive RP1 disease causes RP in the homozygous state, whereas the heterozygous carriers are unaffected, confirming that haploinsufficiency is not the causative mechanism for RP1 disease. We then generated Rp1 knock-in mice with a nonsense Q662X mutation in exon 4, as well as Rp1 transgenic mice carrying a wild-type BAC Rp1 transgene. The Rp1-Q662X allele produces a truncated Rp1 protein, and homozygous Rp1-Q662X mice experience a progressive photoreceptor degeneration characterized disorganization of photoreceptor outer segments. This phenotype could be prevented by expression of a normal amount of Rp1 protein from the BAC transgene without removal of the mutant Rp1-Q662X protein. Over-expression of Rp1 protein in additional BAC Rp1 transgenic lines resulted in retinal degeneration. These findings suggest that the truncated Rp1-Q662X protein does not exert a toxic gain-of-function effect. These results also imply that in principle gene augmentation therapy could be beneficial for both recessive and dominant RP1 patients, but the levels of RP1 protein delivered for therapy will have to be carefully controlled.

  16. Experimental degradation of polymer shopping bags (standard and degradable plastic, and biodegradable) in the gastrointestinal fluids of sea turtles.

    Science.gov (United States)

    Müller, Christin; Townsend, Kathy; Matschullat, Jörg

    2012-02-01

    The persistence of marine debris such as discarded polymer bags has become globally an increasing hazard to marine life. To date, over 177 marine species have been recorded to ingest man-made polymers that cause life-threatening complications such as gut impaction and perforation. This study set out to test the decay characteristics of three common types of shopping bag polymers in sea turtle gastrointestinal fluids (GIF): standard and degradable plastic, and biodegradable. Fluids were obtained from the stomachs, small intestines and large intestines of a freshly dead Green turtle (Chelonia mydas) and a Loggerhead turtle (Caretta caretta). Controls were carried out with salt and freshwater. The degradation rate was measured over 49 days, based on mass loss. Degradation rates of the standard and the degradable plastic bags after 49 days across all treatments and controls were negligible. The biodegradable bags showed mass losses between 3 and 9%. This was a much slower rate than reported by the manufacturers in an industrial composting situation (100% in 49 days). The GIF of the herbivorous Green turtle showed an increased capacity to break down the biodegradable polymer relative to the carnivorous Loggerhead, but at a much lower rate than digestion of natural vegetative matter. While the breakdown rate of biodegradable polymers in the intestinal fluids of sea turtles is greater than standard and degradable plastics, it is proposed that this is not rapid enough to prevent morbidity. Further study is recommended to investigate the speed at which biodegradable polymers decompose outside of industrial composting situations, and their durability in marine and freshwater systems.

  17. Experimental Study on Shear Lag Effect of Partial Cable-Stayed Bridge and Elasto-Plastic Seismic Analysis

    Institute of Scientific and Technical Information of China (English)

    WU Gao-feng; XU Hong; CHEN Xing-chong

    2005-01-01

    The project of Xiaoxihu Yellow River Bridge in Lanzhou is chosen as partial cable-stayed bridge. To get the shear lag effect and anti-earthquake performance of the actual bridge under various loading conditions, organic glass scaled model was adopted to have an experiment and a theory research at one time. The experiment result is the basically same as the theory calculation which proves the FEA method can well calculate shear lag effect and dynamical performance. As a result, because the bridge is located in a seismic area of 8 degree, an elasto-plastic seismic checking is performed by customized FEA program in this paper.

  18. Experimental investigation of the quality characteristics of agricultural plastic wastes regarding their recycling and energy recovery potential.

    Science.gov (United States)

    Briassoulis, D; Hiskakis, M; Babou, E; Antiohos, S K; Papadi, C

    2012-06-01

    A holistic environmentally sound waste management scheme that transforms agricultural plastic waste (APW) streams into labelled guaranteed quality commodities freely traded in open market has been developed by the European research project LabelAgriWaste. The APW quality is defined by the APW material requirements, translated to technical specifications, for recycling or energy recovery. The present work investigates the characteristics of the APW quality and the key factors affecting it from the introduction of the virgin product to the market to the APW stream reaching the disposer. Samples of APW from different countries were traced from their application to the field through their storage phase and transportation to the final destination. The test results showed that the majority of APW retained their mechanical properties after their use preserving a "very good quality" for recycling in terms of degradation. The degree of soil contamination concerning the APW recycling and energy recovery potential fluctuates depending on the agricultural plastic category and application. The chlorine and heavy metal content of the tested APW materials was much lower than the maximum acceptable limits for their potential use in cement industries.

  19. Experimental and Numerical Analysis of Thermal and Hygrometric Characteristics of Building Structures Employing Recycled Plastic Aggregates and Geopolymer Concrete

    Directory of Open Access Journals (Sweden)

    Francesco Colangelo

    2013-11-01

    Full Text Available The correct estimation of building energy consumptions is assuming an always increasing importance, and a detailed reproduction of building structures, with all the single components involved, is necessary to achieve this aim. In addition, the current ecological development tries to limit the use of natural raw materials as building components, in favor of alternative (waste materials, which ensure significant advantages from the economic, energetic and environmental point of views. In this work, dynamic heat and vapor transport in a typical three-dimensional (3D building structure, involving different types of environmental-friendly concrete mixtures, have been simulated by using finite elements. In particular, the authors propose to substitute part of the aggregates with plastic waste and to use a fly ash based geopolymeric binder for the production of low conductivity concrete, to be employed in eco-efficient buildings. Concrete produced with natural limestone aggregates has been considered as the reference benchmark. The whole characterization of the different types of concrete tested in the present work has been obtained through laboratory experiments. The structure taken into account in the simulations is a 3D thermal bridge, typical of building envelopes. The thermal and hygrometric transient behavior of this structure, employing plastic waste in different percentages and geopolymer concrete, has been analyzed by the authors.

  20. Simulation and Experimental on the Solvation Interaction between the GAP Matrix and Insensitive Energetic Plasticizers in Solid Propellants.

    Science.gov (United States)

    Zhao, Yu; Zhang, Xiaohong; Zhang, Wei; Xu, Hongjun; Xie, Wuxi; Du, Jiaojiao; Liu, Yingzhe

    2016-02-11

    Multimethods of simulation and experiment have been performed to investigate the interaction between glycidyl azide polymer (GAP) matrix and insensitive energetic plasticizers N-butyl-N-(2-nitroxy-ethyl)nitramine (Bu-NENA) and bis(2,2-dinitropropyl)formal/acetal (BDNPF/A). To start with, the blending energy distribution and Huggins parameters have been calculated, indicating fine miscibility between the GAP matrix and both plasticizers. The solubility parameter and binding energies show better compatibility between Bu-NENA and the GAP matrix than BDNPF/A, owing to stronger interactions. The interaction mechanism includes both hydrogen bonds and van der Waals forces. The low field NMR physical cross-link density and dynamic rheological behaviors imply larger disentanglement effect of Bu-NENA in the GAP matrix. The dynamic mechanical performance of elastomers show lower glass transition temperature of GAP/Bu-NENA blends, as supportive proof of stronger interactions between the GAP matrix and Bu-NENA in comparison with BDNPF/A.

  1. Simualting the Phase Separated rp-ash

    Science.gov (United States)

    Caplan, Matthew; Horowitz, Chuck; Berry, Donald

    2017-01-01

    The composition and phase separation of rp-ash on accreting neutron stars determine the thermal properties of the crust which must be understood to interpret observations of crust cooling in X-ray bursts. In this work, we report on recent large scale molecular dynamics simulations of the outer crust. Using the crust compositions calculated by Mckinven et al. 2016, we study the structure of the crystal that forms, as well as diffusion and thermal properties of the crust.

  2. Plasticity theory

    CERN Document Server

    Lubliner, Jacob

    2008-01-01

    The aim of Plasticity Theory is to provide a comprehensive introduction to the contemporary state of knowledge in basic plasticity theory and to its applications. It treats several areas not commonly found between the covers of a single book: the physics of plasticity, constitutive theory, dynamic plasticity, large-deformation plasticity, and numerical methods, in addition to a representative survey of problems treated by classical methods, such as elastic-plastic problems, plane plastic flow, and limit analysis; the problem discussed come from areas of interest to mechanical, structural, and

  3. An Experimental Study on the Thermal Performance of Phase-Change Material and Wood-Plastic Composites for Building Roofs

    Directory of Open Access Journals (Sweden)

    Min Hee Chung

    2017-02-01

    Full Text Available We assessed the usefulness of phase-change material (PCM-based thermal plates fabricated from wood-plastic composites (WPCs in mitigating the urban heat island effect. The thermal performance of plates containing PCMs with two different melting temperatures and with two different albedo levels was evaluated. The results showed that the PCM with a melting temperature of 44 °C maintained lower surface and inner temperatures than the PCM with a melting temperature of 25 °C. Moreover, a higher surface albedo resulted in a lower surface temperature. However, the thermal performance of PCMs with different melting temperatures but the same surface albedo did not differ. Using PCM-based materials in roof finishing materials can reduce surface temperatures and improve thermal comfort.

  4. Experimental Reduction of Laser Imprinting and Rayleigh--Taylor Growth in Spherically Compressed, Medium-Z--Doped Plastic Targets

    Science.gov (United States)

    Fiksel, G.; Hu, S. X.; Epstein, R.; Goncharov, V. N.; Meyerhofer, D. D.; Sangster, T. C.; Yaakobi, B.; Bonino, M. J.; Jungquist, R. K.; Smalyuk, V. A.

    2012-10-01

    The effect of medium-Z doping of plastic ablators on laser imprinting and Rayleigh-- Taylor (RT) instability growth was studied using spherical direct-drive implosions on the OMEGA Laser System. The targets were spherical plastic (CH) shells, with an outer diameter of 860 μm and a thickness of 22 μm, doped with a varied concentration of Si (4.3% and 7.4%) and Ge (3.9%). The targets were imploded with 48 beams with a low-adiabat, triple-picket laser shape pulse with a peak intensity of 4 x 10^14 W/cm^2 and a pulse duration of 2.5 ns. The shells were x-ray radiographed through a 400-μm opening in the side of the target. The results show that impurity doping strongly reduces the shell-density modulation and the instability growth rate. The amplitude of the initial imprint is reduced by a factor of 2.5±0.5 for CH[4.3% Si] targets and a factor of 3±0.5 for CH[7.4% Si] and CH[3.9% Ge] targets. At the end of the acceleration phase, the reduction factor becomes 3±0.5 and 5±0.5, correspondingly. The RT instability growth rate in doped targets is reduced by a factor of 1.5 compared to undoped ones. Simulations using the 2-D radiation--hydrodynamics code DRACO show good agreement with the measurements. This work was supported by the U.S. Department of Energy Office of Inertial Confinement Fusion under Cooperative Agreement No. DE-FC52-08NA28302.

  5. Experimental reduction of laser imprinting and Rayleigh-Taylor growth in spherically compressed, medium-Z-doped plastic targets

    Science.gov (United States)

    Fiksel, G.; Hu, S. X.; Goncharov, V. A.; Meyerhofer, D. D.; Sangster, T. C.; Smalyuk, V. A.; Yaakobi, B.; Bonino, M. J.; Jungquist, R.

    2012-06-01

    The effect of medium-Z doping of plastic ablators on laser imprinting and Rayleigh-Taylor (RT) instability growth was studied using spherical direct-drive implosions on the OMEGA Laser System [T. R. Boehly et al., Opt. Commun. 133, 495 (1977)]. The targets were spherical plastic (CH) shells, with an outer diameter of 860 μm and a thickness of 22 μm, volume doped with a varied concentration of Si (4.3% and 7.4%) and Ge (3.9%). The targets were imploded with 48 beams with a low-adiabat, triple-picket laser shape pulse with a peak intensity of 4×1014W/cm2, and a pulse duration of 2.5 ns. The shells were x-ray radiographed through a 400 -μm opening in the side of the target. The results show that volumetric impurity doping strongly reduces the shell density modulation and the instability growth rate. The amplitude of the initial imprint is reduced by a factor of 2.5 ± 0.5 for CH[4.3% Si] targets and by a factor of 3 ± 0.5 for CH[7.4% Si] and CH[3.9% Ge] targets. At the end of the acceleration phase, the reduction factor becomes 3 ± 0.5 and 5 ± 0.5, correspondingly. The RT instability growth rate in doped targets is reduced by a factor of 1.5 compared to undoped ones. Simulations using the two-dimensional, radiation-hydrodynamics code draco show good agreement with the measurements.

  6. Experimental reduction of laser imprinting and Rayleigh-Taylor growth in spherically compressed, medium-Z-doped plastic targets

    Energy Technology Data Exchange (ETDEWEB)

    Fiksel, G.; Hu, S. X.; Goncharov, V. A.; Meyerhofer, D. D.; Sangster, T. C.; Yaakobi, B.; Bonino, M. J.; Jungquist, R. [Laboratory for Laser Energetics, University of Rochester, 250 East River Rd., Rochester, New York 14623-1299 (United States); Smalyuk, V. A. [Lawrence Livermore National Laboratory, Livermore, California 94551 (United States)

    2012-06-15

    The effect of medium-Z doping of plastic ablators on laser imprinting and Rayleigh-Taylor (RT) instability growth was studied using spherical direct-drive implosions on the OMEGA Laser System [T. R. Boehly et al., Opt. Commun. 133, 495 (1977)]. The targets were spherical plastic (CH) shells, with an outer diameter of 860 {mu}m and a thickness of 22 {mu}m, volume doped with a varied concentration of Si (4.3% and 7.4%) and Ge (3.9%). The targets were imploded with 48 beams with a low-adiabat, triple-picket laser shape pulse with a peak intensity of 4 Multiplication-Sign 10{sup 14}W/cm{sup 2}, and a pulse duration of 2.5 ns. The shells were x-ray radiographed through a 400 -{mu}m opening in the side of the target. The results show that volumetric impurity doping strongly reduces the shell density modulation and the instability growth rate. The amplitude of the initial imprint is reduced by a factor of 2.5 {+-} 0.5 for CH[4.3% Si] targets and by a factor of 3 {+-} 0.5 for CH[7.4% Si] and CH[3.9% Ge] targets. At the end of the acceleration phase, the reduction factor becomes 3 {+-} 0.5 and 5 {+-} 0.5, correspondingly. The RT instability growth rate in doped targets is reduced by a factor of 1.5 compared to undoped ones. Simulations using the two-dimensional, radiation-hydrodynamics code draco show good agreement with the measurements.

  7. CERN radiation protection (RP) calibration facilities

    Energy Technology Data Exchange (ETDEWEB)

    Pozzi, Fabio

    2016-04-14

    , the facility was commissioned by measuring the calibration quantities of interest, e.g. H*(10), as a function of the source-to-detector distance. In the case of neutron measurements, a comparison with the Monte Carlo results was carried out; in fact, the neutron scattering can be an important issue and the Monte Carlo method can contribute to its estimation and optimization. Neutron calibrations often need to be performed at neutron energies or spectra very much different from those generated by radioactive sources employed in standard calibration laboratories. Unfortunately, fields with a broad neutron spectrum extending to a few GeVs are very rare and the scientific community is calling for worldwide sharing of the existing facilities. The CERN RP group has been managing the CERN-EU high-energy Reference Field (CERF) facility for 20 years, which is a unique calibration field in its kind. CERF is a workplace field that reproduces the neutron spectrum encountered in the vicinity of high-energy accelerators and at commercial flight altitudes. Within the context of providing a well-characterized workplace field to the scientific community, Monte Carlo simulations were performed with the present development version of the FLUKA code. The simulations were compared with experimental measurements showing promising results for the future ISO accreditation of the facility as workplace reference facility. Even though the accreditation process is fairly long, the work achieved so far is setting the bases to start this process in the right way.

  8. Experimental Study on Drilling Glass Fiber Reinforced Plastics%玻璃纤维增强复合材料钻削试验研究

    Institute of Scientific and Technical Information of China (English)

    宋中权; 程寓; 高超; 金浩

    2011-01-01

    选用S刃钻尖TIN涂层麻花钻对玻璃纤维增强复合材料进行了孔加工试验,并用扫描电子显微镜对孔壁表面进行了微观观察,分析了玻璃纤维破坏机理和切削表面微观结构特征.试验结果表明,S刃钻尖与普通钻尖麻花钻相比,可以有效减小钻削轴向力,减少分层缺陷的发生.因此,S刃钻尖麻花钻适用于玻璃纤维增强复合材料的加工,具有广泛的应用前景.%Drilling trials were carried out on glass fiber reinforced plastics with twist drill which had S shaped drill tip coated by TIN and the ground surfaces of drilled holes were observed by using scanning electron microscope ( SEM ), the fracture mechanism of glass fiber and the microscopic charaeteristics of ground surfaces were analyzed. The experimental results show that twist drill with S shaped drill tip offers less drilling thrust force and delamination fracture campared with conventional twist drills. Therefore,twist drill with S shaped drill tip is suitable for drilling glass fiber reinforced plastics and has a wide application prospect.

  9. Experimental investigations of visco-plastic properties of the aluminium and tungsten alloys used in KE projectiles

    Directory of Open Access Journals (Sweden)

    Magier M.

    2012-08-01

    Full Text Available The main aim of studies on dynamic behaviour of construction materials at high strain rates is to determine the variation of mechanical properties (strength, plasticity in function of the strain rate and temperature. On the basis of results of dynamic tests on the properties of constructional materials the constitutive models are formulated to create numerical codes applied to solve constructional problems with computer simulation methods. In the case of military applications connected with the phenomena of gunshot and terminal ballistics it’s particularly important to develop a model of strength and armour penetration with KE projectile founded on reliable results of dynamic experiments and constituting the base for further analyses and optimization of projectile designs in order to achieve required penetration depth. Static and dynamic results of strength investigations of the EN AW-7012 aluminium alloy (sabot and tungsten alloy (penetrator are discussed in this paper. Static testing was carried out with the INSTRON testing machine. Dynamic tests have been conducted using the split Hopkinson pressure bars technique at strain rates up to 1,2 ⋅ 104s−1 (for aluminium alloy and 6 ⋅ 103s−1 (for tungsten alloy.

  10. Neutral Higgs Sector of the MSSM without $R_{p}$

    CERN Document Server

    Davidson, Sacha; Rius, N

    2000-01-01

    We analyse the neutral scalar sector of the MSSM without R-parity. Our analysis is performed for a one-generation model in terms of ``basis-independent'' parameters, and includes one-loop corrections due to large yukawa couplings. We concentrate on the consequences of large $R_p$ violating masses in the soft sector, which mix the Higgses with the sleptons, because these are only constrained by their one-loop contributions to neutrino masses. We focus on the effect of $R_p$-violation on the Higgs mass and branching ratios. We find that the experimental lower bound on the lightest CP-even Higgs in this model can be lower than in the MSSM.

  11. Plastic Jellyfish.

    Science.gov (United States)

    Moseley, Christine

    2000-01-01

    Presents an environmental science activity designed to enhance students' awareness of the hazards of plastic waste for wildlife in aquatic environments. Discusses how students can take steps to reduce the effects of plastic waste. (WRM)

  12. Characterization of aluminum/RP-1 gel propellant properties

    Science.gov (United States)

    Rapp, Douglas C.; Zurawski, Robert L.

    1988-01-01

    Research efforts are being conducted by the NASA Lewis Research Center to formulate and characterize the properties of Al/RP-1 and RP-1 gelled propellants for rocket propulsion systems. Twenty four different compositions of gelled fuels were formualted with 5 and 16 micron, atomized aluminum powder in RP-1. The total solids concentration in the propellant varied from 5 to 60 wt percent. Tests were conducted to evaluate the stability and rheological characteristics of the fuels. Physical separation of the solids occurred in fuels with less than 50 wt percent solids concentration. The rheological characteristics of the Al/RP-1 fuels varied with solids concentration. Both thixotropic and rheopectic gel behavior were observed. The unmetallized RP-1 gels, which were formulated by a different technique than the Al/RP-1 gels, were highly viscoelastic. A history of research efforts which were conducted to formulate and characterize the properties of metallized propellants for various applications is also given.

  13. Localization of plastic deformation

    Energy Technology Data Exchange (ETDEWEB)

    Rice, J R

    1976-04-01

    The localization of plastic deformation into a shear band is discussed as an instability of plastic flow and a precursor to rupture. Experimental observations are reviewed, a general theoretical framework is presented, and specific calculations of critical conditions are carried out for a variety of material models. The interplay between features of inelastic constitutive description, especially deviations from normality and vertex-like yielding, and the onset of localization is emphasized.

  14. Temperature Jump Pyrolysis Studies of RP 2 Fuel

    Science.gov (United States)

    2017-01-09

    Briefing Charts 3. DATES COVERED (From - To) 15 December 2016 – 11 January 2017 4. TITLE AND SUBTITLE Temperature Jump Pyrolysis Studies of RP-2 Fuel...Rev. 8- 98) Prescribed by ANSI Std. 239.18 1 TEMPERATURE JUMP PYROLYSIS STUDIES OF RP-2 FUEL Owen Pryor1, Steven D. Chambreau2, Ghanshyam L...Mixture Distribution A: Approved for public release; distribution unlimited. PA Clearance 17026 4 RP-2 Pyrolysis /Combustion Chemistries? • Recent

  15. On the Acoustic Filtering of the Pipe and Sensor in a Buried Plastic Water Pipe and its Effect on Leak Detection: An Experimental Investigation

    Science.gov (United States)

    Almeida, Fabrício; Brennan, Michael; Joseph, Phillip; Whitfield, Stuart; Dray, Simon; Paschoalini, Amarildo

    2014-01-01

    Acoustic techniques have been used for many years to find and locate leaks in buried water distribution systems. Hydrophones and accelerometers are typically used as sensors. Although geophones could be used as well, they are not generally used for leak detection. A simple acoustic model of the pipe and the sensors has been proposed previously by some of the authors of this paper, and their model was used to explain some of the features observed in measurements. However, simultaneous measurements of a leak using all three sensor-types in controlled conditions for plastic pipes has not been reported to-date and hence they have not yet been compared directly. This paper fills that gap in knowledge. A set of measurements was made on a bespoke buried plastic water distribution pipe test rig to validate the previously reported analytical model. There is qualitative agreement between the experimental results and the model predictions in terms of the differing filtering properties of the pipe-sensor systems. A quality measure for the data is also presented, which is the ratio of the bandwidth over which the analysis is carried out divided by the centre frequency of this bandwidth. Based on this metric, the accelerometer was found to be the best sensor to use for the test rig described in this paper. However, for a system in which the distance between the sensors is large or the attenuation factor of the system is high, then it would be advantageous to use hydrophones, even though they are invasive sensors. PMID:24658622

  16. On the Acoustic Filtering of the Pipe and Sensor in a Buried Plastic Water Pipe and its Effect on Leak Detection: An Experimental Investigation

    Directory of Open Access Journals (Sweden)

    Fabrício Almeida

    2014-03-01

    Full Text Available Acoustic techniques have been used for many years to find and locate leaks in buried water distribution systems. Hydrophones and accelerometers are typically used as sensors. Although geophones could be used as well, they are not generally used for leak detection. A simple acoustic model of the pipe and the sensors has been proposed previously by some of the authors of this paper, and their model was used to explain some of the features observed in measurements. However, simultaneous measurements of a leak using all three sensor-types in controlled conditions for plastic pipes has not been reported to-date and hence they have not yet been compared directly. This paper fills that gap in knowledge. A set of measurements was made on a bespoke buried plastic water distribution pipe test rig to validate the previously reported analytical model. There is qualitative agreement between the experimental results and the model predictions in terms of the differing filtering properties of the pipe-sensor systems. A quality measure for the data is also presented, which is the ratio of the bandwidth over which the analysis is carried out divided by the centre frequency of this bandwidth. Based on this metric, the accelerometer was found to be the best sensor to use for the test rig described in this paper. However, for a system in which the distance between the sensors is large or the attenuation factor of the system is high, then it would be advantageous to use hydrophones, even though they are invasive sensors.

  17. Not all Laminaria digitata are the same! Phenotypic plasticity and the selection of appropriate surrogate macroalgae for ecohydraulic experimentation

    Science.gov (United States)

    Thomas, Robert E.; McLelland, Stuart J.; Henry, Pierre-Yves T.; Paul, Maike; Eiff, Olivier; Evertsen, Antti-Jussi O.; Aberle, Jochen; Teacă, Adrian

    2015-04-01

    not be transported from Norway to the UK, so we used the same species of live macroalgae harvested from a wave-dominated coast in the UK. These algae exhibited longer, narrower and more flexible blades. The same surrogate plants were used in both the field and flume experiments. In all cases, a profiling ADV was used to collect 45 velocity profiles composed of up to seven 35 mm-high profiles collected for 240 s at 100 Hz, at a streamwise spacing of 0.25 m and cross-stream spacing of 0.20 m. The results show that the live macroalgae in the flume simulation exerted less influence on the flow field than the live macroalgae at the field site. In contrast, the "optimized" surrogate macroalgae behaved similarly to the live algae at the field site and yielded similar mean and turbulent velocity fields as our prototype live macroalgae. This emphasizes both the importance of phenotypic plasticity and the importance of selecting surrogates that adequately represent the mean characteristics of the species of interest.

  18. Crack-induced debonding failure in fiber reinforced plastics (FRP) strengthened concrete beams: Experimental and theoretical analysis

    Science.gov (United States)

    Pan, Jinlong

    External bonding of FRP plates to the tension substrate of RC beams has been accepted as an efficient and effective technique for flexural strengthening. In this thesis, different problems related to crack-induced debonding of the FRP plate in the flexural strengthened concrete beams have been investigated. FRP strengthened RC beam may fail by FRP debonding from the bottom of a major flexural crack in the span. This kind of failure is studied with the direct shear test in the present research work. Our experimental investigation focuses on the effect of concrete composition on the bond behavior between FRP and concrete. Based on the test results, the bond capacity of the specimen is found to be governed by the concrete surface tensile strength, aggregate size and aggregate content. Then, the neural network is employed to derive an empirical expression for the interfacial fracture energy in terms of concrete surface tensile strength and aggregate content. Using the empirical equation, simulated bond capacity is in good agreement with experimental results. In the FRP strengthened RC beams, debonding of the FRP plate often occurs under the presence of multiple cracks along the span. In the present thesis, experimental and theoretical investigations are performed to study the effect of multiple secondary cracks on the debonding behavior and ultimate load capacity. A new analytical model for FRP debonding under multiple cracks has been developed. The effect of the multiple secondary cracks on the shear softening in the debonded zone is explicitly considered in the model. Using the new model, the simulated values of ultimate load when debonding occurs are in good agreement with measured values. In the FRP strengthened RC beams, concrete cover separation or plate end debonding can be avoided by applying tapers at the FRP plate end. In this situation, it is easier for FRP debonding to be induced by a major flexural crack close to the support. To study the effect of the

  19. P2RP: a Web-based framework for the identification and analysis of regulatory proteins in prokaryotic genomes.

    Science.gov (United States)

    Barakat, Mohamed; Ortet, Philippe; Whitworth, David E

    2013-04-20

    Regulatory proteins (RPs) such as transcription factors (TFs) and two-component system (TCS) proteins control how prokaryotic cells respond to changes in their external and/or internal state. Identification and annotation of TFs and TCSs is non-trivial, and between-genome comparisons are often confounded by different standards in annotation. There is a need for user-friendly, fast and convenient tools to allow researchers to overcome the inherent variability in annotation between genome sequences. We have developed the web-server P2RP (Predicted Prokaryotic Regulatory Proteins), which enables users to identify and annotate TFs and TCS proteins within their sequences of interest. Users can input amino acid or genomic DNA sequences, and predicted proteins therein are scanned for the possession of DNA-binding domains and/or TCS domains. RPs identified in this manner are categorised into families, unambiguously annotated, and a detailed description of their features generated, using an integrated software pipeline. P2RP results can then be outputted in user-specified formats. Biologists have an increasing need for fast and intuitively usable tools, which is why P2RP has been developed as an interactive system. As well as assisting experimental biologists to interrogate novel sequence data, it is hoped that P2RP will be built into genome annotation pipelines and re-annotation processes, to increase the consistency of RP annotation in public genomic sequences. P2RP is the first publicly available tool for predicting and analysing RP proteins in users' sequences. The server is freely available and can be accessed along with documentation at http://www.p2rp.org.

  20. Experimental validation of a nonlinear μFE model based on cohesive-frictional plasticity for trabecular bone.

    Science.gov (United States)

    Schwiedrzik, J; Gross, T; Bina, M; Pretterklieber, M; Zysset, P; Pahr, D

    2016-04-01

    Trabecular bone is a porous mineralized tissue playing a major load bearing role in the human body. Prediction of age-related and disease-related fractures and the behavior of bone implant systems needs a thorough understanding of its structure-mechanical property relationships, which can be obtained using microcomputed tomography-based finite element modeling. In this study, a nonlinear model for trabecular bone as a cohesive-frictional material was implemented in a large-scale computational framework and validated by comparison of μFE simulations with experimental tests in uniaxial tension and compression. A good correspondence of stiffness and yield points between simulations and experiments was found for a wide range of bone volume fraction and degree of anisotropy in both tension and compression using a non-calibrated, average set of material parameters. These results demonstrate the ability of the model to capture the effects leading to failure of bone for three anatomical sites and several donors, which may be used to determine the apparent behavior of trabecular bone and its evolution with age, disease, and treatment in the future.

  1. Gas Experiments with Plastic Soda Bottles.

    Science.gov (United States)

    Kavanah, Patrick; Zipp, Arden P.

    1998-01-01

    Describes the use of an inexpensive device consisting of a plastic soda bottle and a modified plastic cap in a range of demonstrations and experimental activities having to do with the behavior of gases. (Author/WRM)

  2. Short vowel placements in RP past and present

    DEFF Research Database (Denmark)

    Fabricius, Anne

    This study addresses diachronic change in the short vowel system of RP. While TRAP lowering and backing in RP has been reported previously, the movements STRUT has undergone have proven more difficult to determine. This study identifies a TRAP/STRUT 'rotation' using acoustic measurements of the s...

  3. Crack Detection in Fibre Reinforced Plastic Structures Using Embedded Fibre Bragg Grating Sensors: Theory, Model Development and Experimental Validation.

    Science.gov (United States)

    Pereira, G F; Mikkelsen, L P; McGugan, M

    2015-01-01

    In a fibre-reinforced polymer (FRP) structure designed using the emerging damage tolerance and structural health monitoring philosophy, sensors and models that describe crack propagation will enable a structure to operate despite the presence of damage by fully exploiting the material's mechanical properties. When applying this concept to different structures, sensor systems and damage types, a combination of damage mechanics, monitoring technology, and modelling is required. The primary objective of this article is to demonstrate such a combination. This article is divided in three main topics: the damage mechanism (delamination of FRP), the structural health monitoring technology (fibre Bragg gratings to detect delamination), and the finite element method model of the structure that incorporates these concepts into a final and integrated damage-monitoring concept. A novel method for assessing a crack growth/damage event in fibre-reinforced polymer or structural adhesive-bonded structures using embedded fibre Bragg grating (FBG) sensors is presented by combining conventional measured parameters, such as wavelength shift, with parameters associated with measurement errors, typically ignored by the end-user. Conjointly, a novel model for sensor output prediction (virtual sensor) was developed using this FBG sensor crack monitoring concept and implemented in a finite element method code. The monitoring method was demonstrated and validated using glass fibre double cantilever beam specimens instrumented with an array of FBG sensors embedded in the material and tested using an experimental fracture procedure. The digital image correlation technique was used to validate the model prediction by correlating the specific sensor response caused by the crack with the developed model.

  4. Crack Detection in Fibre Reinforced Plastic Structures Using Embedded Fibre Bragg Grating Sensors: Theory, Model Development and Experimental Validation.

    Directory of Open Access Journals (Sweden)

    G F Pereira

    Full Text Available In a fibre-reinforced polymer (FRP structure designed using the emerging damage tolerance and structural health monitoring philosophy, sensors and models that describe crack propagation will enable a structure to operate despite the presence of damage by fully exploiting the material's mechanical properties. When applying this concept to different structures, sensor systems and damage types, a combination of damage mechanics, monitoring technology, and modelling is required. The primary objective of this article is to demonstrate such a combination. This article is divided in three main topics: the damage mechanism (delamination of FRP, the structural health monitoring technology (fibre Bragg gratings to detect delamination, and the finite element method model of the structure that incorporates these concepts into a final and integrated damage-monitoring concept. A novel method for assessing a crack growth/damage event in fibre-reinforced polymer or structural adhesive-bonded structures using embedded fibre Bragg grating (FBG sensors is presented by combining conventional measured parameters, such as wavelength shift, with parameters associated with measurement errors, typically ignored by the end-user. Conjointly, a novel model for sensor output prediction (virtual sensor was developed using this FBG sensor crack monitoring concept and implemented in a finite element method code. The monitoring method was demonstrated and validated using glass fibre double cantilever beam specimens instrumented with an array of FBG sensors embedded in the material and tested using an experimental fracture procedure. The digital image correlation technique was used to validate the model prediction by correlating the specific sensor response caused by the crack with the developed model.

  5. Production and β Decay of rp-Process Nuclei Cd96, In98, and Sn100

    Science.gov (United States)

    Bazin, D.; Montes, F.; Becerril, A.; Lorusso, G.; Amthor, A.; Baumann, T.; Crawford, H.; Estrade, A.; Gade, A.; Ginter, T.; Guess, C. J.; Hausmann, M.; Hitt, G. W.; Mantica, P.; Matos, M.; Meharchand, R.; Minamisono, K.; Perdikakis, G.; Pereira, J.; Pinter, J.; Portillo, M.; Schatz, H.; Smith, K.; Stoker, J.; Stolz, A.; Zegers, R. G. T.

    2008-12-01

    The β-decay properties of the N=Z nuclei Cd96, In98, and Sn100 have been studied. These nuclei were produced at the National Superconducting Cyclotron Laboratory by fragmenting a 120MeV/nucleon Sn112 primary beam on a Be target. The resulting radioactive beam was filtered in the A1900 and the newly commissioned Radio Frequency Fragment Separator to achieve a purity level suitable for decay studies. The observed production cross sections of these nuclei are lower than predicted by factors of 10 30. The half-life of Cd96, which was the last experimentally unknown waiting point half-life of the astrophysical rp process, is 1.03-0.21+0.24s. The implications of the experimental T1/2 value of Cd96 on the abundances predicted by rp process calculations and the origin of A=96 isobars such as Ru96 are explored.

  6. Plastic deformation and contact area of an elastic-plastic contact of ellipsoid bodies after unloading

    NARCIS (Netherlands)

    Jamari, Jamari; Schipper, Dirk J.

    2007-01-01

    This paper presents theoretical and experimental results of the residual or plastic deformation and the plastic contact area of an elastic–plastic contact of ellipsoid bodies after unloading. There are three regime responses of the deformation and contact area: elastic, elastic–plastic and fully

  7. Plastics Technology.

    Science.gov (United States)

    Barker, Tommy G.

    This curriculum guide is designed to assist junior high schools industrial arts teachers in planning new courses and revising existing courses in plastics technology. Addressed in the individual units of the guide are the following topics: introduction to production technology; history and development of plastics; safety; youth leadership,…

  8. ACADEMIC TRAINING (R.P. Walker)

    CERN Multimedia

    Françoise Benz

    2002-01-01

    15, 16, 17 May LECTURE SERIES from 11.00 to 12.00 hrs - Council room, bldg. 503 on 15 May, Auditorium, bldg. 500 on 16 and 17 May Introduction to free electron lasers by R.P. Walker / Rutherford Laboratory, UK The Free-electron laser (FEL) is a source of coherent electromagnetic radiation based on a relativistic electron beam. First operated 25 years ago, the FEL has now reached a stage of maturity for operation in the infra-red region of the spectrum and several facilities provide intense FEL radiation beams for research covering a wide range of disciplines. Several projects both underway and proposed aim at pushing the minimum wavelength from its present limit around 100 nm progressively down to the 1 Angstrom region where the X-ray FEL would open up many new and exciting research possibilities. Other developments aim at increasing power levels to the 10's of kW level. In this series of lectures we give an introduction to the basic principles of FELs and their different modes of operation, and summarise the...

  9. Symptoms of Raynaud's phenomenon (RP) in fibromyalgia syndrome are similar to those reported in primary RP despite differences in objective assessment of digital microvascular function and morphology.

    Science.gov (United States)

    Scolnik, M; Vasta, B; Hart, D J; Shipley, J A; McHugh, N J; Pauling, J D

    2016-10-01

    Symptoms of Raynaud's phenomenon (RP) are common in fibromyalgia syndrome (FMS). We compared symptom characteristics and objective assessment of digital microvascular function using infrared thermography (and nailfold capillaroscopy where available) in patients with FMS (reporting RP symptoms) and primary RP. We retrospectively reviewed the outcome of microvascular imaging studies and RP symptom characteristics (captured using patient-completed questionnaire at the time of assessment) for patients with FMS (reporting RP symptoms) and patients with primary RP referred for thermographic assessment of RP symptoms over a 2-year period. Of 257 patients referred for thermographic assessment of RP symptoms between 2010 and 2012, we identified 85 patients with primary RP and 43 patients with FMS. There were no differences in RP symptom characteristics between FMS and primary RP (p > 0.05 for all comparisons). In contrast, patients with FMS had higher baseline temperature of the digits (32.1 vs. 29.0 °C, p = 0.004), dorsum (31.9 vs. 30.2 °C, p = 0.005) and thermal gradient (temperature of digits minus temperature of dorsum; +0.0 vs. -0.9 °C, p = 0.03) compared with primary RP. Significant differences between groups persisted following local cold challenge. In primary RP, patient reporting "blue" digits, bi-phasic and tri-phasic RP was associated with lower digital perfusion. In contrast, no associations between skin temperature and RP digital colour changes/phases were identified in FMS. Our findings suggest that symptoms of RP in FMS may have a different aetiology to those seen in primary RP. These findings have potential implications for both the classification of RP symptoms and the management of RP symptoms in the context of FMS. Digital colour changes reported by patients might reflect the degree of digital microvascular compromise in primary RP.

  10. Discrete dislocation plasticity

    NARCIS (Netherlands)

    van der Giessen, E.; Finel, A; Maziere, D; Veron, M

    2003-01-01

    Conventional continuum mechanics models of inelastic deformation processes axe size scale independent. In contrast, there is considerable experimental evidence that plastic flow in crystalline materials is size dependent over length scales of the order of tens of microns and smaller. At present ther

  11. Multiscale modeling and synaptic plasticity.

    Science.gov (United States)

    Bhalla, Upinder S

    2014-01-01

    Synaptic plasticity is a major convergence point for theory and computation, and the process of plasticity engages physiology, cell, and molecular biology. In its many manifestations, plasticity is at the hub of basic neuroscience questions about memory and development, as well as more medically themed questions of neural damage and recovery. As an important cellular locus of memory, synaptic plasticity has received a huge amount of experimental and theoretical attention. If computational models have tended to pick specific aspects of plasticity, such as STDP, and reduce them to an equation, some experimental studies are equally guilty of oversimplification each time they identify a new molecule and declare it to be the last word in plasticity and learning. Multiscale modeling begins with the acknowledgment that synaptic function spans many levels of signaling, and these are so tightly coupled that we risk losing essential features of plasticity if we focus exclusively on any one level. Despite the technical challenges and gaps in data for model specification, an increasing number of multiscale modeling studies have taken on key questions in plasticity. These have provided new insights, but importantly, they have opened new avenues for questioning. This review discusses a wide range of multiscale models in plasticity, including their technical landscape and their implications.

  12. Plastic bronchitis

    National Research Council Canada - National Science Library

    Singhi, Anil Kumar; Vinoth, Bharathi; Kuruvilla, Sarah; Sivakumar, Kothandam

    2015-01-01

    Plastic bronchitis, a rare but serious clinical condition, commonly seen after Fontan surgeries in children, may be a manifestation of suboptimal adaptation to the cavopulmonary circulation with unfavorable hemodynamics...

  13. Plastic Fishes

    CERN Multimedia

    Trettnak, Wolfgang

    2015-01-01

    In terms of weight, the plastic pollution in the world’s oceans is estimated to be around 300,000 tonnes. This plastic comes from both land-based and ocean-based sources. A lecture at CERN by chemist Wolfgang Trettnak addressed this issue and highlighted the role of art in raising people’s awareness. The slideshow below gives you a taste of the artworks by Wolfgang Trettnak and Margarita Cimadevila.

  14. Plastic Bridge

    Institute of Scientific and Technical Information of China (English)

    履之

    1994-01-01

    Already ubiquitous in homes and cars, plastic is now appearing inbridges. An academic-industrial consortium based at the University ofCalifornia in San Diego is launching a three-year research program aimed atdeveloping the world’s first plastic highway bridge, a 450-foot span madeentirely from glass-,carbon,and polymer-fiber-reinforced composite mate-rials, the stuff of military aircraft. It will cross Interstate 5 to connect thetwo sides of the school’s campus.

  15. Short vowel placements in RP past and present

    DEFF Research Database (Denmark)

    Fabricius, Anne

    This study addresses diachronic change in the short vowel system of RP. While TRAP lowering and backing in RP has been reported previously, the movements STRUT has undergone have proven more difficult to determine. This study identifies a TRAP/STRUT 'rotation' using acoustic measurements of the s......This study addresses diachronic change in the short vowel system of RP. While TRAP lowering and backing in RP has been reported previously, the movements STRUT has undergone have proven more difficult to determine. This study identifies a TRAP/STRUT 'rotation' using acoustic measurements...... of the short vowel space, showing variation across generations and an identifiable direction of change during the course of the 20th century....

  16. Synthesis of RP 48497, an Impurity of Eszopiclone

    Directory of Open Access Journals (Sweden)

    Mao-Sheng Cheng

    2008-08-01

    Full Text Available Abstract: RP 48497 is a photodegradation product of eszopiclone, a non-benzodiazepine sedative-hypnotic used in the treatment of insomnia. We report herein the first synthesis of RP 48497 via reduction, chlorination, and recyclization of 6-(5-chloropyridin-2-yl-7-hydroxy-6,7-dihydropyrrolo[3,4-b]pyrazin-5-one (3, a key intermediate in the synthesis of eszopiclone. The structure of RP 48497 was confirmed by its 1H-NMR and MS data. The mechanism of the reduction step in the synthesis of RP 48497 was also studied and the key parameters were determined. These findings should be important for quality control purposes in the manufacture of eszopiclone.

  17. Thermoplastic Starch Prepared with Different Plasticizers:Relation between Degree of Plasticization and Properties

    Institute of Scientific and Technical Information of China (English)

    ZUO Yingfeng; GU Jiyou; TAN Haiyan; ZHANG Yanhua

    2015-01-01

    Ethylene glycol, glycerol, sorbitol, formamide, and urea were used as plasticizers for the preparation of thermoplastic starch (TPS) from corn starch. The properties of TPS were tested by analysis method. The results showed that TPSs were more highly plasticized with amines than alcohols. For the same type of plasticizer, the degree of plasticization decreased as the molecular weight of plasticizer increased. The relationship between plasticization degree and TPS properties was characterized and described by mechanical properties and water absorption. The experimental results showed that when the degree of plasticization increased, the tensile strength decreased and the elongation at breakage and water absorption increased.

  18. GREEN PLASTIC: A NEW PLASTIC FOR PACKAGING

    OpenAIRE

    Mr. Pankaj Kumar*, Sonia

    2016-01-01

    This paper gives a brief idea about a new type of plastic called as bio-plastic or green plastic. Plastic is used as a packaging material for various products, but this plastic is made up of non renewable raw materials. There are various disadvantages of using conventional plastic like littering, CO2 production, non-degradable in nature etc. To overcome these problems a new type of plastic is discovered called bio-plastic or green plastic. Bio-plastic is made from renewable resources and also...

  19. Plastic condoms.

    Science.gov (United States)

    1968-01-01

    Only simple equipment, simple technology and low initial capital investment are needed in their manufacture. The condoms can be made by people who were previously unskilled or only semi-skilled workers. Plastic condoms differ from those made of latex rubber in that the nature of the plastic film allows unlimited shelf-life. Also, the plastic has a higher degree of lubricity than latex rubber; if there is a demand for extra lubrication in a particular market, this can be provided. Because the plastic is inert, these condoms need not be packaged in hermetically sealed containers. All these attributes make it possible to put these condoms on the distributors' shelves in developing countries competitively with rubber condoms. The shape of the plastic condom is based on that of the lamb caecum, which has long been used as luxury-type condom. The plastic condom is made from plastic film (ethylene ethyl acrilate) of 0.001 inch (0.0254 mm.) thickness. In addition, a rubber ring is provided and sealed into the base of the condom for retention during coitus. The advantage of the plastic condom design and the equipment on which it is made is that production can be carried out either in labour-intensive economy or with varying degrees of mechanization and automation. The uniform, finished condom if made using previously untrained workers. Training of workers can be done in a matter of hours on the two machines which are needed to produce and test the condoms. The plastic film is provided on a double wound roll, and condom blanks are prepared by means of a heat-sealing die on the stamping machine. The rubber rings are united to the condom blanks on an assembly machine, which consists of a mandrel and heat-sealing equipment to seal the rubber ring to the base of the condom. Built into the assembly machine is a simple air-testing apparatus that can detect the smallest pinhole flaw in a condom. The manufacturing process is completed by unravelling the condom from the assembly

  20. Simulation and Analysis of Ring Compression Using RP/RVP Meshless Method

    Institute of Scientific and Technical Information of China (English)

    YANG Yuying; LI Jing

    2006-01-01

    To avoid mesh distortion and iterative remeshing in mesh-based numerical analysis, a meshless approach based on element free Galerkin (EFG) method is applied to the metal forming analysis of ring compression. Discrete equations are formulated upon the moving least-squares (MLS) approximation and modified Markov variational principles for rigid-plastic/ rigid-viscoplastic (RP/RVP) material models. The penalty function is used for the incompressible condition without volumetric locking. Based on the axisymmetric mechanical model, ring tests with different friction coefficients are studied. The deformed nodal configurations and shaded contours of equivalent strains are shown by developed meshless post processor. The comparison of meshless and finite element (FE) results validates the feasibility and accuracy for meshless method to simulate metal forming process.

  1. 分数阶黏弹塑性蠕变模型试验研究%EXPERIMENTAL STUDY OF FRACTIONAL VISCOELASTIC-PLASTIC CREEP MODEL

    Institute of Scientific and Technical Information of China (English)

    吴斐; 谢和平; 刘建锋; 边宇; 裴建良

    2014-01-01

    现行利用等时曲线求长期强度的方法往往有以下两点不足:一是曲线上拐点不明显,确定长期强度带有一定的随意性;二是试验时间偏短、加载级数偏少,结果不够准确。针对湖北江汉盐岩进行为期约5个月的蠕变试验研究,获得较好的试验结果。试验得出的等时曲线上出现明显拐点,由此确定其长期强度。试验时间长和加载级数多有力地保障了试验结果的精度,可为实际工程提供参考。在前人研究成果基础上,通过两点改进建立新的分数阶黏弹塑性蠕变模型。并从推导过程、拟合结果和理论分析3个方面证实了改进后的模型更加简单、合理。%There were usually two drawbacks in calculating the long-term strength through isochronal curves. One was that the inflection point of the isochronal curve was generally not so apparent leading to the determination of the long-term strength with uncertainties. The other was that the testing time was usually short with only few loading steps,so the test results were not accurate enough. Therefore, the creep test to the salt rock from Jianghan in Hubei province in this study was carried out for about five months long. There was an obvious inflection point on the isochronal curve plotted according the test data and the long-term strength was thus determined without uncertainty. The longer testing time and the more loading steps were proved to be the vital measure to guarantee the credibility of the test results. A new fractional viscoelastic-plastic creep model was established according to the experimental results together with the improvements in two aspects. The proposed model was proved to be simpler and more reasonable in terms of the process of derivation,the outcome of test data fitting and the results of theoretical analysis.

  2. Low-lying level structure of 56Cu and its implications for the rp process

    Science.gov (United States)

    Ong, W.-J.; Langer, C.; Montes, F.; Aprahamian, A.; Bardayan, D. W.; Bazin, D.; Brown, B. A.; Browne, J.; Crawford, H.; Cyburt, R.; Deleeuw, E. B.; Domingo-Pardo, C.; Gade, A.; George, S.; Hosmer, P.; Keek, L.; Kontos, A.; Lee, I.-Y.; Lemasson, A.; Lunderberg, E.; Maeda, Y.; Matos, M.; Meisel, Z.; Noji, S.; Nunes, F. M.; Nystrom, A.; Perdikakis, G.; Pereira, J.; Quinn, S. J.; Recchia, F.; Schatz, H.; Scott, M.; Siegl, K.; Simon, A.; Smith, M.; Spyrou, A.; Stevens, J.; Stroberg, S. R.; Weisshaar, D.; Wheeler, J.; Wimmer, K.; Zegers, R. G. T.

    2017-05-01

    The low-lying energy levels of proton-rich 56Cu have been extracted using in-beam γ -ray spectroscopy with the state-of-the-art γ -ray tracking array GRETINA in conjunction with the S800 spectrograph at the National Superconducting Cyclotron Laboratory at Michigan State University. Excited states in 56Cu serve as resonances in the 55Ni(p ,γ )56Cu reaction, which is a part of the rp process in type-I x-ray bursts. To resolve existing ambiguities in the reaction Q value, a more localized isobaric multiplet mass equation (IMME) fit is used, resulting in Q =639 ±82 keV. We derive the first experimentally constrained thermonuclear reaction rate for 55Ni(p ,γ )56Cu . We find that, with this new rate, the rp process may bypass the 56Ni waiting point via the 55Ni(p ,γ ) reaction for typical x-ray burst conditions with a branching of up to ˜40 % . We also identify additional nuclear physics uncertainties that need to be addressed before drawing final conclusions about the rp -process reaction flow in the 56Ni region.

  3. Nuclear binding around the RP-process waiting points $^{68}$Se and $^{72}$Kr

    CERN Multimedia

    2002-01-01

    Encouraged by the success of mass determinations of nuclei close to the Z=N line performed at ISOLTRAP during the year 2000 and of the recent decay spectroscopy studies on neutron-deficient Kr isotopes (IS351 collaboration), we aim to measure masses and proton separation energies of the bottleneck nuclei defining the flow of the astrophysical rp-process beyond A$\\sim$70. In detail, the program includes mass measurements of the rp-process waiting point nuclei $^{68}$Se and $^{72}$Kr and determination of proton separation energies of the proton-unbound $^{69}$Br and $^{73}$Rb via $\\beta$-decays of $^{69}$Kr and $^{73}$Sr, respectively. The aim of the project is to complete the experimental database for astrophysical network calculations and for the liquid-drop type of mass models typically used in the modelling of the astrophysical rp process in the region. The first beamtime is scheduled for the August 2001 and the aim is to measure the absolute mass of the waiting-point nucleus $^{72}$Kr.

  4. Context mediates antimicrobial efficacy of kinocidin congener peptide RP-1.

    Directory of Open Access Journals (Sweden)

    Nannette Y Yount

    Full Text Available Structure-mechanism relationships are key determinants of host defense peptide efficacy. These relationships are influenced by anatomic, physiologic and microbiologic contexts. Structure-mechanism correlates were assessed for the synthetic peptide RP-1, modeled on microbicidal domains of platelet kinocidins. Antimicrobial efficacies and mechanisms of action against susceptible ((S or resistant ((R Salmonella typhimurium (ST, Staphylococcus aureus (SA, and Candida albicans (CA strain pairs were studied at pH 7.5 and 5.5. Although RP-1 was active against all study organisms, it exhibited greater efficacy against bacteria at pH 7.5, but greater efficacy against CA at pH 5.5. RP-1 de-energized SA and CA, but caused hyperpolarization of ST in both pH conditions. However, RP-1 permeabilized ST(S and CA strains at both pH, whereas permeabilization was modest for ST(R or SA strain at either pH. Biochemical analysis, molecular modeling, and FTIR spectroscopy data revealed that RP-1 has indistinguishable net charge and backbone trajectories at pH 5.5 and 7.5. Yet, concordant with organism-specific efficacy, surface plasmon resonance, and FTIR, molecular dynamics revealed modest helical order increases but greater RP-1 avidity and penetration of bacterial than eukaryotic lipid systems, particularly at pH 7.5. The present findings suggest that pH- and target-cell lipid contexts influence selective antimicrobial efficacy and mechanisms of RP-1 action. These findings offer new insights into selective antimicrobial efficacy and context-specificity of antimicrobial peptides in host defense, and support design strategies for potent anti-infective peptides with minimal concomitant cytotoxicity.

  5. Determination of lipophilicity of some new 1,2,4-triazole derivatives by RP-HPLC and RP-TLC and calculated methods

    Directory of Open Access Journals (Sweden)

    Anna M. Hawrył

    2015-06-01

    Full Text Available Experimental and computational approaches were used to estimate the lipophilicity of novel 1,2,4-triazole derivatives. These derivatives have been subjected to this research, because they exhibit antimicrobial activity. The chromatographic analysis of RP-HPLC and RP-TLC was carried out using methanol-water or acetonitrile-water as mobile phase. The linear relationships between logk (or RM values and the concentration of organic modifier were obtained. The lipophilicity was expressed as chromatographically derived descriptors: logkW, S, ϕ0 and scores logk and R_Mcorresponding to the first principal component. The experimental lipophilicity data have been compared with the computer calculated lipophilicity parameters (milogP, clogP, ALOGPs, AClogP, AlogP, MLOGP, KOWWIN, XLOGP2, XLOGP3, logPChS of the same molecules. The matrices were created with logkW or RM0and logP and they have been the subject of PCA analysis.

  6. Plastic Bronchitis.

    Science.gov (United States)

    Rubin, Bruce K

    2016-09-01

    Plastic bronchitis is an uncommon and probably underrecognized disorder, diagnosed by the expectoration or bronchoscopic removal of firm, cohesive, branching casts. It should not be confused with purulent mucous plugging of the airway as seen in patients with cystic fibrosis or bronchiectasis. Few medications have been shown to be effective and some are now recognized as potentially harmful. Current research directions in plastic bronchitis research include understanding the genetics of lymphatic development and maldevelopment, determining how abnormal lymphatic malformations contribute to cast formation, and developing new treatments. Copyright © 2016 Elsevier Inc. All rights reserved.

  7. Theoretical and Experimental Research of Single-effect Lithium Bromide-water Absorption Chillers Using Plastic Pipes%塑料管单效溴化锂吸收式制冷机理论与实验研究

    Institute of Scientific and Technical Information of China (English)

    张雪东

    2009-01-01

    There are extensive applications of lithium bromide-water absorption chillers in industry,but the heat exchanger corrosion and refrigerating capacity loss are very difficult to be solved.In our research,the problem was solved by using plastic heat transfer pipes instead of copper pipes.Theoretical circulation of single-effect lithium bromide-water absorption chillers using plastic pipes was analyzed.Thermal calculation and heat transfer calculation were made for single-effect lithium bromide-water absorption chillers using plastic pipes.The experimental facility of lithium bromide-water absorption chillers using plastic pipes was designed.And these are reference for the performance testing of single-effect lithium bromide-water absorption chillers using plastic pipes.%溴化锂吸收式制冷机在工业中有着广泛的应用,但传热管腐蚀及其引起的冷量衰减一直以来是人们难以解决的问题.采用塑料传热管代替铜传热管有望解决这个难题.分析了单效溴化锂吸收式制冷机的理论循环,对塑料管单效溴化锂吸收式制冷机进行了热力计算和传热计算,设计了塑料管单效溴化锂吸收式制冷机的结构,为塑料管单效溴化锂吸收式制冷机的实验性能测试提供参考依据.

  8. Mixed plastics recycling technology

    CERN Document Server

    Hegberg, Bruce

    1995-01-01

    Presents an overview of mixed plastics recycling technology. In addition, it characterizes mixed plastics wastes and describes collection methods, costs, and markets for reprocessed plastics products.

  9. Dynamic GABAergic afferent modulation of AgRP neurons

    Science.gov (United States)

    Garfield, Alastair S; Shah, Bhavik P; Burgess, Christian R; Li, Monica M; Li, Chia; Steger, Jennifer S; Madara, Joseph C; Campbell, John N; Kroeger, Daniel; Scammell, Thomas E; Tannous, Bakhos A; Myers, Martin G; Andermann, Mark L; Krashes, Michael J; Lowell, Bradford B

    2017-01-01

    Agouti-related peptide (AgRP) neurons of the arcuate nucleus of the hypothalamus (ARC) promote homeostatic feeding at times of caloric insufficiency, yet they are rapidly suppressed by food-related sensory cues prior to ingestion. Here we identify a highly selective inhibitory afferent to AgRP neurons that serves as a neural determinant of this rapid modulation. Specifically, GABAergic projections arising from the ventral compartment of the dorsomedial nucleus of the hypothalamus (vDMH) contribute to the pre-consummatory modulation of ARCAgRP neurons. In a manner reciprocal to ARCAgRP neurons, ARC-projecting leptin receptor (LepR)-expressing GABAergic DMH neurons exhibit rapid activation upon availability of food that additionally reflects the relative value of the food. Thus, DMHLepR neurons form part of the sensory network that relays real-time information about the nature and availability of food to dynamically modulate ARCAgRP neuron activity and feeding behavior. PMID:27643429

  10. The Effect of Hydrogen Addition on the Combustion Characteristics of RP-3 Kerosene/Air Premixed Flames

    Directory of Open Access Journals (Sweden)

    Wen Zeng

    2017-07-01

    Full Text Available Experimental studies have been performed to investigate the effects of hydrogen addition on the combustion characteristics of Chinese No.3 jet fuel (RP-3 kerosene/air premixed flames. Experiments were carried out in a constant volume chamber and the influences of the initial temperatures of 390 and 420 K, initial pressures of 0.1 and 0.3 MPa, equivalence ratios of 0.6–1.6 and hydrogen additions of 0.0–0.5 on the laminar burning velocities, and Markstein numbers of Hydrogen (H2/RP-3/air mixtures were investigated. The results show that the flame front surfaces of RP-3/air mixtures remain smooth throughout the entire flame propagation process at a temperature of 390 K, pressure of 0.3 MPa, equivalence ratio of 1.3 and without hydrogen addition, but when the hydrogen addition increases from 0.0 to 0.5 under the same conditions, flaws and protuberances occur at the flame surfaces. It was also found that with the increase of the equivalence ratio from 0.9 to 1.5, the laminar burning velocities of the mixtures increase at first and then decrease, and the highest laminar burning velocity was measured at an equivalence ratio of 1.2. Meanwhile, with the increase of hydrogen addition, laminar burning velocities of H2/RP-3/air mixtures increase. However, the Markstein numbers of H2/RP-3/air mixtures decrease with the increase of hydrogen addition, which means that the flames of H2/RP-3/air mixtures become unstable with the increase of hydrogen addition.

  11. Plastic fish

    CERN Multimedia

    Antonella Del Rosso

    2015-01-01

    In terms of weight, the plastic pollution in the world’s oceans is estimated to be around 300,000 tonnes. This plastic comes from both land-based and ocean-based sources. A lecture at CERN by chemist Wolfgang Trettnak addressed this issue and highlighted the role of art in raising people’s awareness.   Artwork by Wolfgang Trettnak. Packaging materials, consumer goods (shoes, kids’ toys, etc.), leftovers from fishing and aquaculture activities… our oceans and beaches are full of plastic litter. Most of the debris from beaches is plastic bottles. “PET bottles have high durability and stability,” explains Wolfgang Trettnak, a chemist by education and artist from Austria, who gave a lecture on this topic organised by the Staff Association at CERN on 26 May. “PET degrades very slowly and the estimated lifetime of a bottle is 450 years.” In addition to the beach litter accumulated from human use, rivers bring several ki...

  12. Plastic zonnecellen

    NARCIS (Netherlands)

    Roggen, Marjolein

    1998-01-01

    De zonnecel van de toekomst is in de maak. Onderzoekers van uiteenlopend pluimage werken eendrachtig aan een plastic zonnecel. De basis is technisch gelegd met een optimale, door invallend licht veroorzaakte, vorming van ladingdragers binnen een composiet van polymeren en buckyballs. Nu is het zaak

  13. Plasticity and beyond microstructures, crystal-plasticity and phase transitions

    CERN Document Server

    Hackl, Klaus

    2014-01-01

    The book presents the latest findings in experimental plasticity, crystal plasticity, phase transitions, advanced mathematical modeling of finite plasticity and multi-scale modeling. The associated algorithmic treatment is mainly based on finite element formulations for standard (local approach) as well as for non-standard (non-local approach) continua and for pure macroscopic as well as for directly coupled two-scale boundary value problems. Applications in the area of material design/processing are covered, ranging from grain boundary effects in polycrystals and phase transitions to deep-drawing of multiphase steels by directly taking into account random microstructures.

  14. Swirl Coaxial Injector Testing with LOX/RP-J

    Science.gov (United States)

    Greene, Sandra Elam; Casiano, Matt

    2013-01-01

    Testing was conducted at NASA fs Marshall Space Flight Center (MSFC) in the fall of 2012 to evaluate the operation and performance of liquid oxygen (LOX) and kerosene (RP ]1) in an existing swirl coaxial injector. While selected Russian engines use variations of swirl coaxial injectors, component level performance data has not been readily available, and all previously documented component testing at MSFC with LOX/RP ]1 had been performed using a variety of impinging injector designs. Impinging injectors have been adequate for specific LOX/RP ]1 engine applications, yet swirl coaxial injectors offer easier fabrication efforts, providing cost and schedule savings for hardware development. Swirl coaxial elements also offer more flexibility for design changes. Furthermore, testing with LOX and liquid methane propellants at MSFC showed that a swirl coaxial injector offered improved performance compared to an impinging injector. So, technical interest was generated to see if similar performance gains could be achieved with LOX/RP ]1 using a swirl coaxial injector. Results would allow such injectors to be considered for future engine concepts that require LOX/RP ]1 propellants. Existing injector and chamber hardware was used in the test assemblies. The injector had been tested in previous programs at MSFC using LOX/methane and LOX/hydrogen propellants. Minor modifications were made to the injector to accommodate the required LOX/RP ]1 flows. Mainstage tests were performed over a range of chamber pressures and mixture ratios. Additional testing included detonated gbombs h for stability data. Test results suggested characteristic velocity, C*, efficiencies for the injector were 95 ]97%. The injector also appeared dynamically stable with quick recovery from the pressure perturbations generated in the bomb tests.

  15. Plastic Surgery Statistics

    Science.gov (United States)

    ... PSN PSEN GRAFT Contact Us News Plastic Surgery Statistics Plastic surgery procedural statistics from the American Society of Plastic Surgeons. Statistics by Year Print 2016 Plastic Surgery Statistics 2015 ...

  16. Burnup measurements on spent fuel elements of the RP-10 research reactor

    Energy Technology Data Exchange (ETDEWEB)

    Vela Mora, Mariano; Gallardo Padilla, Alberto; Palomino, Jose Luis Castro, E-mail: mvela@ipen.gob.p [Instituto Peruano de Energia Nuclear (IPEN/Peru), Lima (Peru). Grupo de Calculo, Analisis y Seguridad de Reactores; Terremoto, Luis Antonio Albiac, E-mail: laaterre@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2011-07-01

    This work describes the measurement, using nondestructive gamma-ray spectroscopy, of the average burnup attained by Material Testing Reactor (MTR) fuel elements irradiated in the RP-10 research reactor. Measurements were performed at the reactor storage pool area using {sup 137}Cs as the only burnup monitor, even for spent fuel elements with cooling times much shorter than two years. The experimental apparatus was previously calibrated in efficiency to obtain absolute average burnup values, which were compared against corresponding ones furnished by reactor physics calculations. The mean deviation between both values amounts to 6%. (author)

  17. Radiation protection Group (SC/RP) desperately seeking...

    CERN Multimedia

    A. Hervé, Y. Donjoux / SC

    2006-01-01

    We are trying to trace two transit permits (passavants), which constitute the customs clearance documentation for two 'AD6'portable radiation detectors. The two permits (No. 1308 and No. 1309) were sent in the same internal mail envelope towards the middle of March 2006 but never reached their final destination. After weeks of searching in vain, we are now appealing for your help. If you have these two permits in your possession, please get in touch with us. Many thanks in advance. A.HERVE - SC/RP- ( 163168 / 70927) Y.DONJOUX - SC/RP - (160105 / 73171)

  18. Plastic bronchitis

    Directory of Open Access Journals (Sweden)

    Anil Kumar Singhi

    2015-01-01

    Full Text Available Plastic bronchitis, a rare but serious clinical condition, commonly seen after Fontan surgeries in children, may be a manifestation of suboptimal adaptation to the cavopulmonary circulation with unfavorable hemodynamics. They are ominous with poor prognosis. Sometimes, infection or airway reactivity may provoke cast bronchitis as a two-step insult on a vulnerable vascular bed. In such instances, aggressive management leads to longer survival. This report of cast bronchitis discusses its current understanding.

  19. Numerical Investigation on Supercritical Heat Transfer of RP3 Kerosene Flowing inside a Cooling Channel of Scramjet

    Directory of Open Access Journals (Sweden)

    Ning Wang

    2014-06-01

    Full Text Available Supercritical convective heat transfer characteristics of hydrocarbon fuel play a fundamental role in the active cooling technology of scramjet. In this paper, a 2D-axisymmetric numerical study of supercritical heat transfer of RP3 flowing inside the cooling channels of scramjet has been conducted. The main thermophysical properties of RP3, including density, specific heat, and thermal conductivity, are obtained from experimental data, while viscosity is evaluated from a commercial code with a ten-species surrogate. Effects of heat flux, mass flow rate, and inlet temperature on supercritical heat transfer processes have been investigated. Results indicate that when the wall temperature rises above the pseudocritical temperature of RP3, heat transfer coefficient decreases as a result of drastic decrease of the specific heat. The conventional heat transfer correlations, that is, Gnielinski formula, are no longer proper for the supercritical heat transfer of RP3. The modified Jackson and Hall formula, which was proposed for supercritical CO2 and water, gives good prediction except when the wall temperature is near or higher than the pseudocritical temperature.

  20. Fabricating Complete Dentures with CAD/CAM and RP Technologies.

    Science.gov (United States)

    Bilgin, Mehmet Selim; Erdem, Ali; Aglarci, Osman Sami; Dilber, Erhan

    2015-06-01

    Two techological approaches for fabricating dentures; computer-aided design and computer-aided manufacturing (CAD/CAM) and rapid prototyping (RP), are combined with the conventional techniques of impression and jaw relation recording to determine their feasibility and applicability. Maxillary and mandibular edentulous jaw models were produced using silicone molds. After obtaining a gypsum working model, acrylic bases were crafted, and occlusal rims for each model were fabricated with previously determined standard vertical and centric relationships. The maxillary and mandibular relationships were recorded with guides. The occlusal rims were then scanned with a digital scanner. The alignment of the maxillary and mandibular teeth was verified. The teeth in each arch were fabricated in one piece, or set, either by CAM or RP. Conventional waxing and flasking was then performed for both methods. These techniques obviate a practitioner's need for technicians during design and provide the patient with an opportunity to participate in esthetic design with the dentist. In addition, CAD/CAM and RP reduce chair time; however, the materials and techniques need further improvements. Both CAD/CAM and RP techniques seem promising for reducing chair time and allowing the patient to participate in esthetics design. Furthermore, the one-set aligned artificial tooth design may increase the acrylic's durability.

  1. RIGID-PLASTIC/RIGID-VISCOPLASTIC FEM BASED ON LINEAR PROGRAMMING-THEORETICAL MODELING AND APPLICATION FOR PLANE-STRAIN PROBLEMS

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    A new rigid-plastic/rigid-viscoplastic (RP/RVP) FEM based on linear programming (LP) for plane-strain metal forming simulation is proposed. Compared with the traditional RP/RVP FEM based on iteration solution, it has some remarkable advantages, such as it's free of convergence problem and its convenience in contact, incompressibility constraint and rigid zone treatment. Two solution examples are provided to validate its accuracy and efficiency.

  2. Assessment of the Compositional Variability of RP-1 and RP-2 with the Advanced Distillation Curve Approach

    Science.gov (United States)

    2010-04-21

    infrared spectrophotometry (FTIR), or nuclear magnetic resonance spectroscopy (NMR). We have applied the advanced distillation curve method to a wide...colorless (no dye is added to this fuel). RP-2 was also analyzed by gas chromatography-mass spectrometry- infrared spectrophotometry (30 m capillary

  3. RIGID-PLASTIC/RIGID-VISCOPLASTIC FEM BASED ON LINEAR PROGRAMMING—THEORETICAL MODELING AND APPLICATION FOR AXISYMMETRICAL PROBLEMS

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Compared with the traditional rigid-plastic/rigid-viscoplastic(RP/RVP) FEM(based on iteration solution),RP/RVP FEM based on linear programming (LP) has some remarkable advantages,such as it's free of convergence problem and its convenience in contact,rigid zone,and friction force treatment.The numerical model of RP/RVP FEM based on LP for axisymmetrical metal forming simulation is studied,and some related key factors and its treatment methods in formulation of constraint condition are proposed.Some solution examples are provided to validate its accuracy and efficiency.

  4. TLR accessory molecule RP105 (CD180 is involved in post-interventional vascular remodeling and soluble RP105 modulates neointima formation.

    Directory of Open Access Journals (Sweden)

    Jacco C Karper

    Full Text Available BACKGROUND: RP105 (CD180 is TLR4 homologue lacking the intracellular TLR4 signaling domain and acts a TLR accessory molecule and physiological inhibitor of TLR4-signaling. The role of RP105 in vascular remodeling, in particular post-interventional remodeling is unknown. METHODS AND RESULTS: TLR4 and RP105 are expressed on vascular smooth muscle cells (VSMC as well as in the media of murine femoral artery segments as detected by qPCR and immunohistochemistry. Furthermore, the response to the TLR4 ligand LPS was stronger in VSMC from RP105(-/- mice resulting in a higher proliferation rate. In RP105(-/- mice femoral artery cuff placement resulted in an increase in neointima formation as compared to WT mice (4982 ± 974 µm(2 vs.1947 ± 278 µm(2,p = 0.0014. Local LPS application augmented neointima formation in both groups, but in RP105(-/- mice this effect was more pronounced (10316±1243 µm(2 vs.4208 ± 555 µm(2,p = 0.0002, suggesting a functional role for RP105. For additional functional studies, the extracellular domain of murine RP105 was expressed with or without its adaptor protein MD1 and purified. SEC-MALSanalysis showed a functional 2∶2 homodimer formation of the RP105-MD1 complex. This protein complex was able to block the TLR4 response in whole blood ex-vivo. In vivo gene transfer of plasmid vectors encoding the extracellular part of RP105 and its adaptor protein MD1 were performed to initiate a stable endogenous soluble protein production. Expression of soluble RP105-MD1 resulted in a significant reduction in neointima formation in hypercholesterolemic mice (2500 ± 573 vs.6581 ± 1894 µm(2,p<0.05, whereas expression of the single factors RP105 or MD1 had no effect. CONCLUSION: RP105 is a potent inhibitor of post-interventional neointima formation.

  5. The Experimental Study of Plastic Plate Solar Collector%塑料太阳能平板集热器试验研究

    Institute of Scientific and Technical Information of China (English)

    李久锋; 陈观生; 张国庆

    2015-01-01

    According to the undemanding heating rate of heat-storage solar water heater, a new type of plastic plate solar collector was designed.Under the condition of intermittent forced circulation, test on the performance of this collector was carried out and instantaneous efficiency curves were obtained.As a result, the average daily collector efficiency is 51%~55% and the temperature of tank is 45.8~50.2 ℃, which serve as a reference for the application of plastic plate solar collector.%针对蓄热型太阳能热水器对升温速率要求不高的特点,提出并研制了一种新型塑料太阳能平板集热器.在间歇性强制循环条件下,对该集热器进行性能测试,获得了瞬时效率曲线.在试验条件下,该集热器的日平均效率为51%~55%,水箱温度为45.8~50.2℃,可以为塑料平板集热器的实际应用提供依据.

  6. Exceptional plasticity of silicon nanobridges

    Energy Technology Data Exchange (ETDEWEB)

    Ishida, Tadashi; Sato, Takaaki; Toshiyoshi, Hiroshi; Collard, Dominique; Fujita, Hiroyuki [University of Tokyo, Institute of Industrial Science, 4-6-1 Komaba Meguro, Tokyo 153-8505 (Japan); Cleri, Fabrizio [Institut d' Electronique Microelectronique et Nanotechnologie (CNRS UMR 8520), Universite de Lille I, Avenue Poincare BP60069 59652 Villeneuve d' Ascq (France); Kakushima, Kuniyuki [Tokyo Institute of Technology, 4259, Nagatsuda, Midori, Yokohama, Kanagawa 226-8502 (Japan); Mita, Makoto [Department of Spacecraft Engineering, Japan Aerospace Exploration Agency, 3-1-1, Yoshinodai, Sagamihara, Kanagawa 229-8510 (Japan); Miyata, Masaki; Itamura, Noriaki; Sasaki, Naruo [Department of Materials and Life Sciences, Seikei University, 3-3-1, Kitamachi, Kichijoji, Musashino, Tokyo 180-8633 (Japan); Endo, Junji, E-mail: tadashii@iis.u-tokyo.ac.jp [FK Optical laboratory, 1-13-4 Nakano Niiza Saitama, 352-0005 (Japan)

    2011-09-02

    The plasticity of covalently bonded materials is a subject at the forefront of materials science, bearing on a wide range of technological and fundamental aspects. However, covalent materials fracture in a brittle manner when the deformation exceeds just a few per cent. It is predicted that a macroscopically brittle material like silicon can show nanoscale plasticity. Here we report the exceptional plasticity observed in silicon nanocontacts ('nanobridges') at room temperature using a special experimental setup combining a transmission electron microscope and a microelectromechanical system. When accounting for surface diffusion, we succeeded in elongating the nanocontact into a wire-like structure, with a fivefold increase in volume, up to more than twenty times the original length. Such a large plasticity was caused by the stress-assisted diffusion and the sliding of the intergranular, amorphous-like material among the nanocrystals.

  7. Microstructural Characteristics of High Rate Plastic Deformation in Elektron (trademark) WE43 Magnesium Alloy

    Science.gov (United States)

    2012-04-01

    Microstructural Characteristics of High Rate Plastic Deformation in Elektron ™ WE43 Magnesium Alloy by Joseph Hamilton, Sarah T. Brennan...Ground, MD 21005-5069 ARL-RP-363 April 2012 Microstructural Characteristics of High Rate Plastic Deformation in Elektron ™ WE43 Magnesium...Alloy Joseph Hamilton, Sara T. Brennan, and Yongho Sohn University of Central Florida Bruce Davis and Rick DeLorme Magnesium Elektron North

  8. Determination of log P values of new cyclen based antimalarial drug leads using RP-HPLC.

    Science.gov (United States)

    Rudraraju, A V; Amoyaw, P N A; Hubin, T J; Khan, M O F

    2014-09-01

    Lipophilicity, expressed by log P, is an important physicochemical property of drugs that affects many biological processes, including drug absorption and distribution. The main purpose of this study to determine the log P values of newly discovered drug leads using reversed-phase high-performance liquid chromatography (RP-HPLC). The reference standards, with varying polarity ranges, were dissolved in methanol and analyzed by RP-HPLC using a C18 column. The mobile phase consisted of a mixture of acetonitrile, methanol and water in a gradient elution mode. A calibration curve was plotted between the experimental log P values and obtained log k values of the reference standard compounds and a best fit line was obtained. The log k values of the new drug leads were determined in the same solvent system and were used to calculate the respective log P values by using the best fit equation. The log P vs. log k data gave a best fit linear curve that had an R2 of 0.9786 with Pvalues of the intercept and slope of 1.19 x 10(-6) and 1.56 x 10(-10), respectively, at 0.05 level of significance. Log P values of 15 new drug leads and related compounds, all of which are derivatives of macrocyclic polyamines and their metal complexes, were determined. The values obtained are closely related to the calculated log P (Clog P) values using ChemDraw Ultra 12.0. This experiment provided efficient, fast and reasonable estimates of log P values of the new drug leads by using RP-HPLC.

  9. Constraints on the evolution of phenotypic plasticity: limits and costs of phenotype and plasticity.

    Science.gov (United States)

    Murren, C J; Auld, J R; Callahan, H; Ghalambor, C K; Handelsman, C A; Heskel, M A; Kingsolver, J G; Maclean, H J; Masel, J; Maughan, H; Pfennig, D W; Relyea, R A; Seiter, S; Snell-Rood, E; Steiner, U K; Schlichting, C D

    2015-10-01

    Phenotypic plasticity is ubiquitous and generally regarded as a key mechanism for enabling organisms to survive in the face of environmental change. Because no organism is infinitely or ideally plastic, theory suggests that there must be limits (for example, the lack of ability to produce an optimal trait) to the evolution of phenotypic plasticity, or that plasticity may have inherent significant costs. Yet numerous experimental studies have not detected widespread costs. Explicitly differentiating plasticity costs from phenotype costs, we re-evaluate fundamental questions of the limits to the evolution of plasticity and of generalists vs specialists. We advocate for the view that relaxed selection and variable selection intensities are likely more important constraints to the evolution of plasticity than the costs of plasticity. Some forms of plasticity, such as learning, may be inherently costly. In addition, we examine opportunities to offset costs of phenotypes through ontogeny, amelioration of phenotypic costs across environments, and the condition-dependent hypothesis. We propose avenues of further inquiry in the limits of plasticity using new and classic methods of ecological parameterization, phylogenetics and omics in the context of answering questions on the constraints of plasticity. Given plasticity's key role in coping with environmental change, approaches spanning the spectrum from applied to basic will greatly enrich our understanding of the evolution of plasticity and resolve our understanding of limits.

  10. Overcoming maladaptive plasticity through plastic compensation

    Directory of Open Access Journals (Sweden)

    Matthew R.J. MORRIS, Sean M. ROGERS

    2013-08-01

    Full Text Available Most species evolve within fluctuating environments, and have developed adaptations to meet the challenges posed by environmental heterogeneity. One such adaptation is phenotypic plasticity, or the ability of a single genotype to produce multiple environmentally-induced phenotypes. Yet, not all plasticity is adaptive. Despite the renewed interest in adaptive phenotypic plasticity and its consequences for evolution, much less is known about maladaptive plasticity. However, maladaptive plasticity is likely an important driver of phenotypic similarity among populations living in different environments. This paper traces four strategies for overcoming maladaptive plasticity that result in phenotypic similarity, two of which involve genetic changes (standing genetic variation, genetic compensation and two of which do not (standing epigenetic variation, plastic compensation. Plastic compensation is defined as adaptive plasticity overcoming maladaptive plasticity. In particular, plastic compensation may increase the likelihood of genetic compensation by facilitating population persistence. We provide key terms to disentangle these aspects of phenotypic plasticity and introduce examples to reinforce the potential importance of plastic compensation for understanding evolutionary change [Current Zoology 59 (4: 526–536, 2013].

  11. Overcoming maladaptive plasticity through plastic compensation

    Institute of Scientific and Technical Information of China (English)

    Matthew R.J.MORRIS; Sean M.ROGERS

    2013-01-01

    Most species evolve within fluctuating environments,and have developed adaptations to meet the challenges posed by environmental heterogeneity.One such adaptation is phenotypic plasticity,or the ability of a single genotype to produce multiple environmentally-induced phenotypes.Yet,not all plasticity is adaptive.Despite the renewed interest in adaptive phenotypic plasticity and its consequences for evolution,much less is known about maladaptive plasticity.However,maladaptive plasticity is likely an important driver of phenotypic similarity among populations living in different environments.This paper traces four strategies for overcoming maladaptive plasticity that result in phenotypic similarity,two of which involve genetic changes (standing genetic variation,genetic compensation) and two of which do not (standing epigenetic variation,plastic compensation).Plastic compensation is defined as adaptive plasticity overcoming maladaptive plasticity.In particular,plastic compensation may increase the likelihood of genetic compensation by facilitating population persistence.We provide key terms to disentangle these aspects of phenotypic plasticity and introduce examples to reinforce the potential importance of plastic compensation for understanding evolutionary change.

  12. Thermal Stability of RP-2 for Hydrocarbon Boost Regenerative Cooling

    Science.gov (United States)

    Kleinhenz, Julie E.; Deans, Matthew C.; Stiegemeier, Benjamin R.; Psaras, Peter M.

    2013-01-01

    A series of tests were performed in the NASA Glenn Research Centers Heated Tube Facility to study the heat transfer and thermal stability behavior of RP-2 under conditions similar to those found in rocket engine cooling channels. It has long been known that hydrocarbon fuels, such as RP-2, can decompose at high temperature to form deposits (coke) which can adversely impact rocket engine cooling channel performance. The heated tube facility provides a simple means to study these effects. Using resistively heated copper tubes in a vacuum chamber, flowing RP-2 was heated to explore thermal effects at a range of test conditions. Wall temperature (850-1050F) and bulk fluid temperature (300-500F) were varied to define thermal decomposition and stability at each condition. Flow velocity and pressure were fixed at 75 fts and 1000 psia, respectively. Additionally, five different batches of RP-2 were tested at identical conditions to examine any thermal stability differences resulting from batch to batch compositional variation. Among these tests was one with a potential coke reducing additive known as 1,2,3,4-Tetrahydroquinoline (THQ). While copper tubes were used for the majority of tests, two exploratory tests were performed with a copper alloy known as GRCop-42. Each tube was instrumented with 15 thermocouples to examine the temperature profile, and carbon deposition at each thermocouple location was determined post-test in an oxidation furnace. In many tests, intermittent local temperature increases were observed visually and in the thermocouple data. These hot spots did not appear to correspond with a higher carbon deposition.

  13. Lipophilicity determination of N-( benzothiazol-2-yl )-α-amino alkyl phosphonic diesters by RP-HPLC and RP-HPTLC

    Institute of Scientific and Technical Information of China (English)

    张玲; 李在国; 黄润秋; 王琴孙

    2000-01-01

    Using methanol-water mixtures as the mobile phase, the chromatographic retebtion parameters k' and R1 were determ1ined by reversed-phase high-perfor mance liquid chromatography (RP-HPLC) and reversed-phase high-performance thin-layer chromatograhy (RP-HPILC) for N-(benzothiazol-2-yl)-α-amino alkyl phosphonic diesters and the correlation with lipophilicity parameter (ClogP) was established. Logk wues obtained from RP-HPLC and Rmo values obtained from RP-HPTLC can be used to evaluate the lipophilicity of this kind of compounds. Chromatographic method is a good alternaive for lipophilicity measurement.

  14. RP TLC-based lipophilicity assessment of some natural and synthetic coumarins

    Energy Technology Data Exchange (ETDEWEB)

    Rabtti, El Hadi M.A.; Natic, Maja M.; Milojkovic-Opsenica, Dusanka M.; Trifkovic, Jelena D.; Vuckovic, Ivan M.; Tesic, Zivoslav Lj., E-mail: ztesic@chem.bg.ac.rs [Faculty of Chemistry, University of Belgrade, Belgrade (Serbia); Vajs, Vlatka E. [Institute of Chemistry, Technology and Metallurgy, University of Belgrade, Belgrade (Serbia)

    2012-03-15

    The lipophilic character of twelve coumarins was investigated by reversed-phase thin-layer chromatography (RP TLC) on RP-18 silica. The three different binary solvent systems composed of water and organic modifier (methanol, tetrahydrofuran or acetonitrile) were used in order to determine retention parameter (R{sub M}{sup 0}) and octanol-water partition coefficient (log P{sub OW})as a measure of the lipophilicity of the tested compounds. Lipophilicity parameter (log P{sub OW}) was experimentally determined using eight standard solutes with known log P{sub OW} values which were analyzed under the same chromatographic conditions as the target substances. Lipophilicity parameters together with 2D molecular descriptors were subjected to the multivariate statistical analysis (principal component analysis (PCA) and partial least square (PLS) regression) in order to reveal the most influential factors governing the retention, i.e., lipophilicity of the investigated compounds. The quantitative structure-retention relationship models reveal the importance of descriptors which describe the size and the shape of the molecule as well as their polar properties. (author)

  15. Recycling of Plastic

    DEFF Research Database (Denmark)

    Christensen, Thomas Højlund; Fruergaard, Thilde

    2011-01-01

    Plastic is produced from fossil oil. Plastic is used for many different products. Some plastic products like, for example, wrapping foil, bags and disposable containers for food and beverage have very short lifetimes and thus constitute a major fraction of most waste. Other plastic products like......, good strength and long durability. Recycling of plastic waste from production is well-established, while recycling of postconsumer plastic waste still is in its infancy. This chapter describes briefly how plastic is produced and how waste plastic is recycled in the industry. Quality requirements...

  16. Experimental Research on Early-age Plastic Shrinkage Cracking of Pre-Mixed Mortar by Slab Test Method%预拌砂浆早期塑性收缩开裂平板法试验研究

    Institute of Scientific and Technical Information of China (English)

    吴其峰; 张航

    2014-01-01

    基于平板开裂试验方法,采用正交设计研究了不同因素对预拌砂浆早期塑性收缩开裂的影响。试验结果表明,砂细度模数2.6,粉煤灰I级和外加剂掺量1.2%能有效抑制塑性裂缝的产生和扩展,显著提高砂浆抵抗塑性开裂的能力。%Based on the experimental method of slab test method, the effects of different factors on the plastic shrinkage cracking of pre-mixed mortar were researched by using orthogonal design.The results indicated that sand fineness modulus 2.6,class I fly ash and admixture dosage 1.2% restrained the generation and propagation of plastic shrinkage cracking effectively and improved the crack resistance ability of pre-mixed mortar obviously.

  17. Artificial epi-Retinal Prosthesis (AeRP)

    Science.gov (United States)

    Doorish, John F.

    2006-09-01

    There are several research projects going on around the world, which are attempting to develop a prosthetic device to restore sight to the blind. This paper describes the efforts of Second Sight of New York, Inc. The device being developed is called an Artificial epi-Retinal Prosthesis (AeRP), which is basically a small optical computer that fits into the intraocular space of the eye. The AeRP is designed to draw light into the device by specially designed fibre optics. The light is ‘digitized’ by the fibre optic system and then directed to individual photodiode cells making up concentric cylinders thus providing several hundred photodiode cells in the device. The produced electrical stimulation from each cell is then delivered to the retinal ganglion cells by a specially designed delivery system utilizing electrically conducting polymer strands (ECP), which sit on an ‘umbrella’ at the back of the device. The retinal ganglion cells receive the electrical stimulation, which would then be transmitted through the visual system of the brain. There are several innovations in this approach as compared to the other projects. They include, first the design, which will allow for a high number of PC to produce electrical stimulation that will stimulate multiple RGC per PC; the use of the ECP strands has not been used in such an approach before this. Tests have revealed that nerve cells have a good affinity for the material of the ECP. The use of the ECP as well as the fact that the AeRP is completely photovoltaic, with no external power sources, implies that there will not be high heat build-up in the back of the eye, which might damage RGC. A smaller version of the AeRP called the Mini epi-Retinal Prosthesis (MeRP) is the subject of a complimentary paper. It is being built now and will be tested in cell culture studies to determine the efficacy of the design and materials. No actual implants have been performed yet.

  18. RP1 Is a Phosphorylation Target of CK2 and Is Involved in Cell Adhesion

    Science.gov (United States)

    Göttig, Stephan; Henschler, Reinhard; Markuly, Norbert; Kleber, Sascha; Faust, Michael; Mischo, Axel; Bauer, Stefan; Zweifel, Martin; Knuth, Alexander; Renner, Christoph; Wadle, Andreas

    2013-01-01

    RP1 (synonym: MAPRE2, EB2) is a member of the microtubule binding EB1 protein family, which interacts with APC, a key regulatory molecule in the Wnt signalling pathway. While the other EB1 proteins are well characterized the cellular function and regulation of RP1 remain speculative to date. However, recently RP1 has been implicated in pancreatic cancerogenesis. CK2 is a pleiotropic kinase involved in adhesion, proliferation and anti-apoptosis. Overexpression of protein kinase CK2 is a hallmark of many cancers and supports the malignant phenotype of tumor cells. In this study we investigate the interaction of protein kinase CK2 with RP1 and demonstrate that CK2 phosphorylates RP1 at Ser236 in vitro. Stable RP1 expression in cell lines leads to a significant cleavage and down-regulation of N-cadherin and impaired adhesion. Cells expressing a Phospho-mimicking point mutant RP1-ASP236 show a marked decrease of adhesion to endothelial cells under shear stress. Inversely, we found that the cells under shear stress downregulate endogenous RP1, most likely to improve cellular adhesion. Accordingly, when RP1 expression is suppressed by shRNA, cells lacking RP1 display significantly increased cell adherence to surfaces. In summary, RP1 phosphorylation at Ser236 by CK2 seems to play a significant role in cell adhesion and might initiate new insights in the CK2 and EB1 family protein association. PMID:23844040

  19. RP1 is a phosphorylation target of CK2 and is involved in cell adhesion.

    Directory of Open Access Journals (Sweden)

    Frank Stenner

    Full Text Available RP1 (synonym: MAPRE2, EB2 is a member of the microtubule binding EB1 protein family, which interacts with APC, a key regulatory molecule in the Wnt signalling pathway. While the other EB1 proteins are well characterized the cellular function and regulation of RP1 remain speculative to date. However, recently RP1 has been implicated in pancreatic cancerogenesis. CK2 is a pleiotropic kinase involved in adhesion, proliferation and anti-apoptosis. Overexpression of protein kinase CK2 is a hallmark of many cancers and supports the malignant phenotype of tumor cells. In this study we investigate the interaction of protein kinase CK2 with RP1 and demonstrate that CK2 phosphorylates RP1 at Ser(236 in vitro. Stable RP1 expression in cell lines leads to a significant cleavage and down-regulation of N-cadherin and impaired adhesion. Cells expressing a Phospho-mimicking point mutant RP1-ASP(236 show a marked decrease of adhesion to endothelial cells under shear stress. Inversely, we found that the cells under shear stress downregulate endogenous RP1, most likely to improve cellular adhesion. Accordingly, when RP1 expression is suppressed by shRNA, cells lacking RP1 display significantly increased cell adherence to surfaces. In summary, RP1 phosphorylation at Ser(236 by CK2 seems to play a significant role in cell adhesion and might initiate new insights in the CK2 and EB1 family protein association.

  20. Phosphorylation and protonation of neighboring MiRP2 sites: function and pathophysiology of MiRP2-Kv3.4 potassium channels in periodic paralysis.

    Science.gov (United States)

    Abbott, Geoffrey W; Butler, Margaret H; Goldstein, Steve A N

    2006-02-01

    MinK-related peptide 2 (MiRP2) and Kv3.4 subunits assemble in skeletal muscle to create subthreshold, voltage-gated potassium channels. MiRP2 acts on Kv3.4 to shift the voltage dependence of activation, speed recovery from inactivation, suppress cumulative inactivation and increase unitary conductance. We previously found an R83H missense mutation in MiRP2 that segregated with periodic paralysis in two families and diminished the effects of MiRP2 on Kv3.4. Here we show that MiRP2 has a single, functional PKC phosphorylation site at serine 82 and that normal MiRP2-Kv3.4 function requires phosphorylation of the site. The R83H variant does not prevent PKC phosphorylation of neighboring S82; rather, the change shifts the voltage dependence of activation and endows MiRP2-Kv3.4 channels with sensitivity to changes in intracellular pH across the physiological range. Thus, current passed by single R83H channels decreases as internal pH is lowered (pK(a) approximately 7.3, consistent with histidine protonation) whereas wild-type channels are largely insensitive. These findings identify a key regulatory domain in MiRP2 and suggest a mechanistic link between acidosis and episodes of periodic paralysis.

  1. 聚氨酯泡沫塑料填料的改性试验研究%Experimental Study on Modification of Polyurethane Foam Plastics Carriers

    Institute of Scientific and Technical Information of China (English)

    成国栋; 王芬; 李超; 汪泳; 赵贞地; 季民

    2012-01-01

    The conventional polyurethane foam plastic carrier was modified by chemical oxidation and gelatin protein grafting technology, and the surface physicochemical properties of the carrier, the speed of biofilm formation, the quantity of biofilm and the performance in treating wastewater were investigated before and after the modification. The results showed that the ratio of C - 0 bond on surface of the modified carrier was increased by 47. 86% , and the ratios of C - C and C - H bonds on surface of the modified carrier were reduced by 50. 66%. Hydrophilicity and surface roughness of the carrier were increased after the modification. Compared with the original carrier, the quantity of biofilm on the modified carrier was increased by 30% , the average growth rate of biofilm was increased by 47% , and the removal rates of COD and ammonia nitrogen were increased.%采用化学氧化-明胶蛋白接枝技术对普通聚氨酯泡沫塑料填料进行改性,并对改性前后填料的表面特性、挂膜速度、生物膜量及除污性能等进行研究.结果发现,改性填料表面的C-O键所占比例提高了47.86%,C-C、C-H键所占比例下降了50.66%;改性填料的表面粗糙度以及亲水性提高;与未改性填料相比,改性填料的生物膜量提高了30%,生物膜量的平均增长速率提高了47%;与未改性填料相比,改性填料对COD和氨氮的去除率均有所提高.

  2. RP-based Abrading Technique for Graphite EDM Electrode

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Traditional processes for machining mold cavities are lengthy and costly. EDM (electro-discharge machining) is the most commonly used technique to obtain complex mold cavities. However, some electrodes are difficult to fabricate because of the complexity. Applying RP (rapid prototyping) technology to fabricate an abrading tool which is used to abrade graphite EDM electrodes, the cost and cycle time can greatly be reduced. The paper describes the work being conducted in this area by the authors. This technique will find widespread application in rapid steel mold manufacturing.

  3. Disorientations and work-hardening behaviour during severe plastic deformation

    DEFF Research Database (Denmark)

    Pantleon, Wolfgang

    2012-01-01

    Orientation differences develop during plastic deformation even in grains of originally uniform orientation. The evolution of these disorientations is modelled by dislocation dynamics taking into account different storage mechanisms. The predicted average disorientation angles across different...... types of boundaries are in agreement with experimental data for small and moderate plastic strains. At large plastic strains after severe plastic deformation, saturation of the measured average disorientation angle is observed. This saturation is explained as an immediate consequence of the restriction...

  4. On-line Chip based 2D RP/RP LC-MS/MS Method for Proteomic Analysis

    Science.gov (United States)

    Hunter, Christie; Albanese, Jenny; van Soest, Remco; Zhu, Xiang

    2013-01-01

    Two-dimensional (2D) liquid chromatography is widely used for proteome identification and quantification using the advantage of increasing peak capacity. Herein, we developed an simplified chip based 2D-LC workflow using a high pH/RP first dimensional separation and low pH/RP secondary dimension coupled to mass spectrometer for proteomic analysis. The 2D LC separation was performed using ekspert™ nanoLC 425(Eksigent, part of AB SCIEX) system. Digested E. coli cell lysates were first loaded onto a 200μm × 15cm C18 column at pH 9.8 with a flowrate of 1 μL/min. Step gradient was used to sequentially elute peptide fractions, which were diluted to pH 2.5 before being captured by a 200μm × 6mm C18 chip trap column. Each fraction was then separated with a 75 μm × 15cm C18 chip column at 300 nL/min and analyzed with TripleTOF® 5600 (AB SCIEX). Data was processed with ProteinPilot™ Software (AB SCIEX). The preliminary result suggested the on-line 2D RP-RP method as an easy and competitive approach for proteome discovery. The comparison experiments of 1D, 2D-6 fraction and 2D-10 fraction were performed. Using ∼1ug of E. coli digested cell lysates, there are 1.8× and 2.1× increase in the identification numbers for 2D-6 and 2D-10 fractions versus the 1D configuration at the peptide level (5% local FDR). The other advantage of 2D workflow is the larger sample loading capacities on the column. When the loading amount was increased by 10×, the number of detected peptides increased by 3.3× and 4× for the 2D 6 and 10 fraction workflows, respectively, over 1D workflow. The measured retention time of peptides detected in both the 1D 1ug and 2D 10ug experiments showed very good correlation (r2 0.99, slope 1.0). Further optimization of both the first and second dimension is ongoing to further improve the peptide detection rates.

  5. 多次弹塑性撞击实验系统的设计与数值仿真%Design and Numerical Simulation of Experimental System for Multiple Elastic-plastic Impacts

    Institute of Scientific and Technical Information of China (English)

    戚晓利; 尹晓春; 王文; 杨海波; 沈煜年; 汪敏; 张兴权

    2012-01-01

    A set of experimental system is designed for testing the sub-impact behavior and the systematic dynamical responses in the flexible impact process. The numerical 3-D dynamic finite element simulations show that the experimental system can excite multiple elastic-plastic impacts and effectively simulate the sub-impacts of several typical impact systems. The influence of the materials and the supporting ways of the test beam on the impact process is simulated and the performance index for testing the impact force and beam displacement are determined.%为了实验测量柔性撞击过程中的次撞击行为及其动力学响应,该文设计了一套多次弹塑性撞击实验系统.对该实验系统进行的三维动力有限元数值仿真结果表明,该系统可以激发出多次弹塑性撞击,有效地模拟几种典型构件之间的次撞击行为.采用数值仿真方法研究了测试梁材料、支承方式等对次撞击过程的影响,确定了满足实验要求的撞击力和梁位移测试性能指标.

  6. Recycling of Plastic

    DEFF Research Database (Denmark)

    Christensen, Thomas Højlund; Fruergaard, Thilde

    2011-01-01

    Plastic is produced from fossil oil. Plastic is used for many different products. Some plastic products like, for example, wrapping foil, bags and disposable containers for food and beverage have very short lifetimes and thus constitute a major fraction of most waste. Other plastic products like......, for example, gutters, window frames, car parts and transportation boxes have long lifetimes and thus appear as waste only many years after they have been introduced on the market. Plastic is constantly being used for new products because of its attractive material properties: relatively cheap, easy to form......, good strength and long durability. Recycling of plastic waste from production is well-established, while recycling of postconsumer plastic waste still is in its infancy. This chapter describes briefly how plastic is produced and how waste plastic is recycled in the industry. Quality requirements...

  7. MinK, MiRP1, and MiRP2 diversify Kv3.1 and Kv3.2 potassium channel gating.

    Science.gov (United States)

    Lewis, Anthony; McCrossan, Zoe A; Abbott, Geoffrey W

    2004-02-27

    High frequency firing in mammalian neurons requires ultra-rapid delayed rectifier potassium currents generated by homomeric or heteromeric assemblies of Kv3.1 and Kv3.2 potassium channel alpha subunits. Kv3.1 alpha subunits can also form slower activating channels by coassembling with MinK-related peptide 2 (MiRP2), a single transmembrane domain potassium channel ancillary subunit. Here, using channel subunits cloned from rat and expressed in Chinese hamster ovary cells, we show that modulation by MinK, MiRP1, and MiRP2 is a general mechanism for slowing of Kv3.1 and Kv3.2 channel activation and deactivation and acceleration of inactivation, creating a functionally diverse range of channel complexes. MiRP1 also negatively shifts the voltage dependence of Kv3.1 and Kv3.2 channel activation. Furthermore, MinK, MiRP1, and MiRP2 each form channels with Kv3.1-Kv3.2 heteromers that are kinetically distinct from one another and from MiRP/homomeric Kv3 channels. The findings illustrate a mechanism for dynamic expansion of the functional repertoire of Kv3.1 and Kv3.2 potassium currents and suggest roles for these alpha subunits outside the scope of sustained rapid neuronal firing.

  8. Increased RP105-Negative B Cells in IgG4-Related Disease.

    Science.gov (United States)

    Koarada, S; Tashiro, S; Nagao, N; Suematsu, R; Ohta, A; Tada, Y

    2013-01-01

    Four patients with IgG4-related disease (IgG4-RD) showed increased percentages of RP105-negative B cells in the peripheral blood. Case 1: A 66-year-old man having retroperitoneal fibrosis had 18.8% of RP105-negative B cells. Oral prednisolone improved the affected lesions and the percentage of RP105-negative B cells decreased (3.2%) after the treatment. Case 2: A 53-year-old man with retroperitoneal fibrosis had 27.9% of RP105-negative B cells. Case 3: A 38-year-old man with follicular hyperplasia showed increased percentage of RP105-negative B cells (8.3%). Case 4: A 60-year-old man with interstitial nephritis had 27.5% of RP105-negative B cells. The treatment decreased the numbers of RP105-negative B cells. Increased numbers of RP105-negatvie B cells is possibly associated with disease activity of IgG4-RD. Analysis of expression of RP105 on B cells may be helpful in evaluation of disease activity of IgG4-RD.

  9. Metallized Gelled Propellants: Oxygen/RP-1/Aluminum Rocket Heat Transfer and Combustion Measurements

    Science.gov (United States)

    Palaszewski, Bryan; Zakany, James S.

    1996-01-01

    A series of rocket engine heat transfer experiments using metallized gelled liquid propellants was conducted. These experiments used a small 20- to 40-lb/f thrust engine composed of a modular injector, igniter, chamber and nozzle. The fuels used were traditional liquid RP-1 and gelled RP-1 with 0-, 5-, and 55-percentage by weight loadings of aluminum particles. Gaseous oxygen was used as the oxidizer. Three different injectors were used during the testing: one for the baseline O(2)/RP-1 tests and two for the gelled and metallized gelled fuel firings. Heat transfer measurements were made with a rocket engine calorimeter chamber and nozzle with a total of 31 cooling channels. Each chamber used a water flow to carry heat away from the chamber and the attached thermocouples and flow meters allowed heat flux estimates at each of the 31 stations. The rocket engine Cstar efficiency for the RP-1 fuel was in the 65-69 percent range, while the gelled 0 percent by weight RP-1 and the 5-percent by weight RP-1 exhibited a Cstar efficiency range of 60 to 62% and 65 to 67%, respectively. The 55-percent by weight RP-1 fuel delivered a 42-47% Cstar efficiency. Comparisons of the heat flux and temperature profiles of the RP-1 and the metallized gelled RP-1/A1 fuels show that the peak nozzle heat fluxes with the metallized gelled O2/RP-1/A1 propellants are substantially higher than the baseline O2/RP-1: up to double the flux for the 55 percent by weight RP-1/A1 over the RP-1 fuel. Analyses showed that the heat transfer to the wall was significantly different for the RP-1/A1 at 55-percent by weight versus the RP-1 fuel. Also, a gellant and an aluminum combustion delay was inferred in the 0 percent and 5-percent by weight RP-1/A1 cases from the decrease in heat flux in the first part of the chamber. A large decrease in heat flux in the last half of the chamber was caused by fuel deposition in the chamber and nozzle. The engine combustion occurred well downstream of the injector face

  10. Targeted RP9 ablation and mutagenesis in mouse photoreceptor cells by CRISPR-Cas9

    Science.gov (United States)

    Lv, Ji-Neng; Zhou, Gao-Hui; Chen, Xuejiao; Chen, Hui; Wu, Kun-Chao; Xiang, Lue; Lei, Xin-Lan; Zhang, Xiao; Wu, Rong-Han; Jin, Zi-Bing

    2017-01-01

    Precursor messenger RNA (Pre-mRNA) splicing is an essential biological process in eukaryotic cells. Genetic mutations in many spliceosome genes confer human eye diseases. Mutations in the pre-mRNA splicing factor, RP9 (also known as PAP1), predispose autosomal dominant retinitis pigmentosa (adRP) with an early onset and severe vision loss. However, underlying molecular mechanisms of the RP9 mutation causing photoreceptor degeneration remains fully unknown. Here, we utilize the CRISPR/Cas9 system to generate both the Rp9 gene knockout (KO) and point mutation knock in (KI) (Rp9, c.A386T, P.H129L) which is analogous to the reported one in the retinitis pigmentosa patients (RP9, c.A410T, P.H137L) in 661 W retinal photoreceptor cells in vitro. We found that proliferation and migration were significantly decreased in the mutated cells. Gene expression profiling by RNA-Seq demonstrated that RP associated genes, Fscn2 and Bbs2, were down-regulated in the mutated cells. Furthermore, pre-mRNA splicing of the Fscn2 gene was markedly affected. Our findings reveal a functional relationship between the ubiquitously expressing RP9 and the disease-specific gene, thereafter provide a new insight of disease mechanism in RP9-related retinitis pigmentosa. PMID:28216641

  11. 77 FR 54930 - Carlyle Plastics and Resins, Formerly Known as Fortis Plastics, A Subsidiary of Plastics...

    Science.gov (United States)

    2012-09-06

    ... Employment and Training Administration Carlyle Plastics and Resins, Formerly Known as Fortis Plastics, A... plastic parts. New information shows that Fortis Plastics is now called Carlyle Plastics and Resins. In... of Carlyle Plastics and Resins, formerly known as Fortis Plastics, a subsidiary of...

  12. Functional and molecular plasticity of gamma and alpha-1 GABAA receptor subunits in the dorsal motor nucleus of the vagus after experimentally-induced diabetes.

    Science.gov (United States)

    Boychuk, Carie R; Smith, Katalin Cs; Smith, Bret N

    2017-08-23

    Chronic experimentally-induced hyperglycemia augments subunit specific gamma-aminobutyric acid A (GABAA) receptor-mediated inhibition of parasympathetic preganglionic motor neurons in the dorsal motor nucleus of the vagus (DMV). However, the contribution of α1 or γ GABAA receptor subunits, which are ubiquitously expressed on central nervous system neurons, to this elevation in inhibitory tone have not been determined. This study investigated the effect of chronic hyperglycemia/hypoinsulinemia on α1- and γ-subunit specific GABAA receptor-mediated inhibition using electrophysiological recordings in vitro and quantitative (q)RT-PCR. DMV neurons from streptozotocin-treated mice demonstrated enhancement of both phasic and tonic inhibitory currents in response to application of the α1-subunit selective GABAA receptor positive allosteric modulator, zolpidem. Responses to low concentrations of the GABAA receptor antagonist, gabazine suggested an additional increased contribution of γ-subunit-containing receptors to tonic currents in DMV neurons. Consistent with the functional elevation in α1- and γ-subunit-dependent activity, transcription of both the α1- and γ2-subunits was increased in the dorsal vagal complex of streptozotocin-treated mice. Overall these findings suggest an increased sensitivity to both zolpidem and gabazine after several days of hyperglycemia/hypoinsulinemia, which could contribute to altered parasympathetic output from DMV neurons in diabetes. Copyright © 2017, Journal of Neurophysiology.

  13. Mass measurements of neutron-deficient radionuclides near the end-point of the rp-process with SHIPTRAP

    Energy Technology Data Exchange (ETDEWEB)

    Martin, A.; Ackermann, D.; Block, M.; Di, Z.; Herfurth, F.; Hessberger, F.P.; Hofmann, S.; Mazzocco, M.; Mukherjee, M.; Rahaman, S.; Rauth, C. [Gesellschaft fuer Schwerionenforschung mbH, Darmstadt (Germany); Audi, G. [IN2P3-CNRS UPS, CSNSM, Orsay Campus (France); Blaum, K. [Gesellschaft fuer Schwerionenforschung mbH, Darmstadt (Germany); Johannes-Gutenberg-Universtitaet, Institut fuer Physik, Mainz (Germany); Chaudhuri, A.; Schweikhard, L. [Ernst-Moritz-Arndt-Universtitaet, Institut fuer Physik, Greifswald (Germany); Eliseev, S.; Vorobjev, G. [Gesellschaft fuer Schwerionenforschung mbH, Darmstadt (Germany); St. Petersburg Nuclear Physics Institute, Gatchina (Russian Federation); Ferrer, R.; Weber, C. [Johannes-Gutenberg-Universtitaet, Institut fuer Physik, Mainz (Germany); Habs, D.; Neumayr, J.B.; Thirolf, P.G. [Ludwig-Maximilians-Universitaet Muenchen, Department fuer Physik der, Garching (Germany); Kluge, H.J. [Gesellschaft fuer Schwerionenforschung mbH, Darmstadt (Germany); Universitaet Heidelberg, Physikalisches Institut, Heidelberg (Germany); Novikov, Yu. [St. Petersburg Nuclear Physics Institute, Gatchina (Russian Federation); Plass, W. [Justus-Liebig-Universitaet Giessen, II. Physikalisches Institut, Giessen (Germany); Rodriguez, D. [IN2P3, LPC-ENSICAEN, Caen Cedex (France); Scheidenberger, C. [Gesellschaft fuer Schwerionenforschung mbH, Darmstadt (Germany); Justus-Liebig-Universitaet Giessen, II. Physikalisches Institut, Giessen (Germany)

    2007-12-15

    Direct mass measurements of nuclides near to the supposed end-point region of the astrophysical rp-process were performed at SHIPTRAP, the Penning trap mass spectrometer at GSI Darmstadt. The masses of 24 nuclides were measured with relative uncertainties between 5.10{sup -8} and 2.10{sup -7}. Three of them, {sup 107}Sb, {sup 111}I and {sup 112}I, were determined experimentally for the first time. The data analysis and mass evaluation are presented in detail. (orig.)

  14. Our plastic age

    National Research Council Canada - National Science Library

    Richard C. Thompson; Shanna H. Swan; Charles J. Moore; Frederick S. vom Saal

    2009-01-01

    Within the last few decades, plastics have revolutionized our daily lives. Globally we use in excess of 260 million tonnes of plastic per annum, accounting for approximately 8 per cent of world oil production...

  15. Weinig plastic in vissenmaag

    NARCIS (Netherlands)

    Foekema, E.M.

    2012-01-01

    Waar de magen van sommige zeevogels vol plastic zitten, lijken vissen in de Noordzee nauwelijks last te hebben van kunststofafval. Onderzoekers die plastic resten zochten in vissenmagen vonden ze in elk geval nauwelijks.

  16. Ear Plastic Surgery

    Science.gov (United States)

    ... ENTCareers Marketplace Find an ENT Doctor Near You Ear Plastic Surgery Ear Plastic Surgery Patient Health Information ... they may improve appearance and self-confidence. Can Ear Deformities Be Corrected? Formation of the ear during ...

  17. Modulation of seizures and synaptic plasticity by adenosinergic receptors in an experimental model of temporal lobe epilepsy induced by pilocarpine in rats.

    Science.gov (United States)

    Vianna, Eduardo Paulo Morowsky; Ferreira, Alice Teixeira; Doná, Flávia; Cavalheiro, Esper Abrão; da Silva Fernandes, Maria José

    2005-01-01

    Adenosine is a major negative neuromodulator of synaptic activity in the central nervous system and can exert anticonvulsant and neuroprotective effects in many experimental models of epilepsy. Extracellular adenosine can be formed by a membrane-anchored enzyme ecto-5'-nucleotidase. The purposes of this study were to characterize the role of adenosine receptors in modulating status epilepticus (SE) induced by pilocarpine and evaluate its neuroprotective action. Ecto-5'-nucleotidase activity was studied during the different phases of pilocarpine-induced epilepsy in rats. Adult rats were pretreated with different adenosinergic agents to evaluate the latency and incidence of SE induced by pilocarpine in rats. The neuroprotective effect also was evaluated. A proconvulsant effect was observed with DPCPX and DMPX that reduced the latency of SE in almost all rats. Pretreatment with the MRS 1220 did not alter the incidence of SE but reduced the latency to develop SE. An anticonvulsant and neuroprotective effect was detected with R-PIA. Rats pretreated with R-PIA had a decreased number of apoptotic cells in the hippocampus, whereas pretreatment with DPCPX did not modify the hippocampal damage. An intensification of neuronal death was observed in the dentate gyrus and CA3 when rats were pretreated with DMPX. MRS-1220 did not modify the number of apoptotic cells in the hippocampus. An increase in the ecto-5 -nucleotidase staining was detected in the hippocampus during silent and chronic phases. The present data show that adenosine released during pilocarpine-induced SE via A1-receptor stimulation can exhibit neuroprotective and anticonvulsant roles. Similar effects could also be inferred with A2a and A3 adenosinergic agents, but further experiments are necessary to confirm their roles. Ecto-5 -nucleotidase activity during silent and chronic phases might have a role in blocking spontaneous seizures by production of inhibitory neuromodulator adenosine, besides taking part in

  18. Indirect rp-process Rate Measurements from Single Neutron Removal

    Science.gov (United States)

    Amthor, A. M.; Bazin, D.; Becerril, A.; Cole, A.; Cook, J.; Estrade, A.; Gade, A.; Howard, M.; Lorusso, G.; Matos, M.; Pereira, J.; Portillo, M.; Schatz, H.; Sherrill, B.; Smith, K.; Stolz, A.; Weisshaar, D.; Zegers, R. G. T.; Galaviz, D.; Chen, A.; Fulop, Zs.; Smith, E.; Wiescher, M.

    2007-10-01

    The structure of nuclei along the rp-process path in Type I X-ray bursts has been studied using neutron removal from radioactive beams produced at the National Superconducting Cyclotron Laboratory. Recently, ^37Ca and ^36K have been studied in this way to reduce the uncertainty in ^35Ar(p,γ)^36K and ^36K(p,γ)^37Ca reaction rates, which are important during burst rise. Under burst conditions these rates are dominated by resonant capture contributions from individual resonances because of the low level density just above the proton threshold, precluding the use of statistical methods based on level density to determine the reaction rates. Therefore, precise structure measurements are required to reduce the orders of magnitude rate uncertainty in these key reactions and thereby constrain X-ray burst models. Preliminary results will be presented along with the implications for X-ray burst models.

  19. RP process studies with radioactive beams at ATLAS

    Energy Technology Data Exchange (ETDEWEB)

    Rehm, K.E. [Argonne National Lab., Physics Div., Argonne, IL (United States)

    1998-06-01

    Reactions of interest to nuclear astrophysics have been studied with radioactive beams at the ATLAS accelerator. Using a modified ISOL technique, beams of {sup 18}F(T{sub 1/2}=110 min) and {sup 56}Ni(T{sub 1/2}=6.1 d) have been produced. The reactions {sup 18}F(p,{alpha}){sup 15}O, {sup 18}F(p,{gamma}){sup 19}Ne, and {sup 56}Ni(d,p){sup 57}Ni have been investigated. The results indicate that the {sup 18}F(p,{gamma}) route is a small contributor to the breakout from the hot CNO cycle into the rp process, while the {sup 56}Ni(p,{gamma}){sup 57}Cu rate is about ten times larger than previously assumed. (orig.)

  20. Medical implants by using RP and investment casting technologies

    Directory of Open Access Journals (Sweden)

    Milan Horacek

    2011-02-01

    Full Text Available The paper deals with the production technology of knee joint replacement by using rapid prototyping technology. The aim of the work is to outline the manufacturing technology intended for prototype production with the use of rapid prototyping and investment casting technology for use in orthopaedics and the surgery of knee joint replacement. The research results should make an effective contribution in the attempts to minimize the invasive surgical procedure, shorten the production of knee joint replacement as well as reduce the cost. At present, the research is focused on the preparation of STL data from CT (Computed Tomography and verification of the production technology of prototypes made using available RP technology and its evaluation.

  1. Identification of Rhodiola species by using RP-HPLC

    Institute of Scientific and Technical Information of China (English)

    WANG Qiang; RUAN Xiao; JIN Zhi-hua; YAN Qi-chuan; TU Shan-jun

    2005-01-01

    An approach was established using RP-HPLC (reversed-phase high-performance liquid chromatography) to identify ten species ofRhodiola, R. coccinea A. Bor, R.junggarica C.Y. Yang et N.R. Cui spn., R. heterodonta A. Bor, R. linearifolia A.Bor, R. pamiro alaiucm A. Bor, R. kaschgarica A. Bor, R. litwinowii A. Bor, R. gelida schrenk, R. rosea L. and R. quadrifide Fisch et Mey collected from the Tianshan Mountains areas of China. Chromatograms of alcohol-soluble proteins, generated from these ten Rhodiola spp. were compared. Each chromatogram of alcohol-soluble proteins came from a single seed of one wild species only. The results showed that when using a Waters Delta Pak. C18, 5 μm particle size reversed phase column (150 mmnx3.9 mm),a linear gradient of 22%-55% solvent B with a flow rate of 1 ml/min and a run time of 67 min, the chromatography gave optimum separation of Rhodiola alcohol-soluble proteins. Chromatogram of each species was different and could be used to identify those species. Cluster analysis of genetic similarity coefficients of 37% to 60% showed a medium degree of genetic diversity among the species in these eco-areas. Cluster analysis showed that the ten species of Rhodiola can be divided into four clusters and yielded the general and unique biochemical markers of these species. RP-HPLC was shown to be a rapid, repeatable and reliable method for Rhodiola species identification and analysis of genetic diversity.

  2. Biodegradability of Plastics

    OpenAIRE

    Yutaka Tokiwa; Calabia, Buenaventurada P.; Charles U. Ugwu; Seiichi Aiba

    2009-01-01

    Plastic is a broad name given to different polymers with high molecular weight, which can be degraded by various processes. However, considering their abundance in the environment and their specificity in attacking plastics, biodegradation of plastics by microorganisms and enzymes seems to be the most effective process. When plastics are used as substrates for microorganisms, evaluation of their biodegradability should not only be based on their chemical structure, but also on their physical ...

  3. Chemical Recycle of Plastics

    Directory of Open Access Journals (Sweden)

    Sara Fatima

    2014-11-01

    Full Text Available Various chemical processes currently prevalent in the chemical industry for plastics recycling have been discussed. Possible future scenarios in chemical recycling have also been discussed. Also analyzed are the effects on the environment, the risks, costs and benefits of PVC recycling. Also listed are the various types of plastics and which plastics are safe to use and which not after rcycle

  4. 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...

  5. Nano-plastics in the aquatic environment.

    Science.gov (United States)

    Mattsson, K; Hansson, L-A; Cedervall, T

    2015-10-01

    The amount of plastics released to the environment in modern days has increased substantially since the development of modern plastics in the early 1900s. As a result, concerns have been raised by the public about the impact of plastics on nature and on, specifically, aquatic wildlife. Lately, much attention has been paid to macro- and micro-sized plastics and their impact on aquatic organisms. However, micro-sized plastics degrade subsequently into nano-sizes whereas nano-sized particles may be released directly into nature. Such particles have a different impact on aquatic organisms than larger pieces of plastic due to their small size, high surface curvature, and large surface area. This review describes the possible sources of nano-sized plastic, its distribution and behavior in nature, the impact of nano-sized plastic on the well-being of aquatic organisms, and the difference of impact between nano- and micro-sized particles. We also identify research areas which urgently need more attention and suggest experimental methods to obtain useful data.

  6. Integrating Hebbian and homeostatic plasticity: introduction.

    Science.gov (United States)

    Fox, Kevin; Stryker, Michael

    2017-03-05

    Hebbian plasticity is widely considered to be the mechanism by which information can be coded and retained in neurons in the brain. Homeostatic plasticity moves the neuron back towards its original state following a perturbation, including perturbations produced by Hebbian plasticity. How then does homeostatic plasticity avoid erasing the Hebbian coded information? To understand how plasticity works in the brain, and therefore to understand learning, memory, sensory adaptation, development and recovery from injury, requires development of a theory of plasticity that integrates both forms of plasticity into a whole. In April 2016, a group of computational and experimental neuroscientists met in London at a discussion meeting hosted by the Royal Society to identify the critical questions in the field and to frame the research agenda for the next steps. Here, we provide a brief introduction to the papers arising from the meeting and highlight some of the themes to have emerged from the discussions.This article is part of the themed issue 'Integrating Hebbian and homeostatic plasticity'. © 2017 The Author(s).

  7. Lipophilicity measurement of drugs by reversed phase HPLC over Wide pH range using an alkaline-resistant silica-based stationary phase, XBridge Shield RP(18).

    Science.gov (United States)

    Liu, Xiangli; Hefesha, Hossam; Tanaka, Hideji; Scriba, Gerhard; Fahr, Alfred

    2008-10-01

    We propose a reversed phase HPLC (RP-HPLC) with an alkaline-resistant silica-based stationary phase, XBridge Shield RP(18), for the determination of the lipophilicity of drugs with diverse chemical nature ranging from acidic to basic. A set of 40 model compounds with well-defined solvatochromic parameters was selected to allow a broad distribution of structural properties. The chromatographic results showed that the lipophilicity index log k(w) obtained with XBridge Shield RP(18) was well correlated with experimental log P(oct) values (r(2)=0.96). Linear solvation free-energy relationship (LSER) analyses revealed that the retention mechanism of the stationary phase and 1-octanol/water partitioning were controlled by almost the same balance of intermolecular forces (hydrophobicity as expressed by the van der Waals volume V(w), H-bond acceptor basicity beta, and dipolarity/polarizability pi*). The results showed that XBridge Shield RP(18) phase overcomes the shortcomings of the silica-based stationary phases, the application of which to lipophilicity measurements had been limited to neutral and acidic compounds.

  8. Assessment of the effect of azo dye RP2B on the growth of a nitrogen fixing cyanobacterium--Anabaena sp.

    Science.gov (United States)

    Hu, T L; Wu, S C

    2001-03-01

    Certain nitrogen fixing cyanobacteria are diazotrophic, which profoundly impacts the aquatic ecosystem chemically and biologically. Although certain types are banned due to their carcinogenicity, azo dyes are commonly used in the dyeing or textile industry. This work investigates the effect of azo dye on the growth of cyanobacteria. Anabaena sp. isolated from the Da Jia Brook is an odor producing, nitrogen fixing cyanobacterium. The growth rates of Anabaena sp. in the media with or without nitrogen source were 3.56 x 10(-2) mg/ml day and 2.44 x 10(-2) mg/ml day, respectively. Anabaena sp. could not use azo dye RP2B as the nitrogen source. Experimental results indicated that the growth of Anabaena sp. was inhibited in the medium containing RP2B. The degree of inhibition increased from 50% to 81% with an increasing concentration of RP2B (0-50 mg/l). The IC-50 (inhibitory concentration) of RP2B on the growth of Anabaena sp. was 5 mg/l (as based on dry weight) or 7 mg/l (as measured by chlorophyll a).

  9. Use of biopartitioning micellar chromatography and RP-HPLC for the determination of blood-brain barrier penetration of α-adrenergic/imidazoline receptor ligands, and QSPR analysis.

    Science.gov (United States)

    Vucicevic, J; Popovic, M; Nikolic, K; Filipic, S; Obradovic, D; Agbaba, D

    2017-03-01

    For this study, 31 compounds, including 16 imidazoline/α-adrenergic receptor (IRs/α-ARs) ligands and 15 central nervous system (CNS) drugs, were characterized in terms of the retention factors (k) obtained using biopartitioning micellar and classical reversed phase chromatography (log kBMC and log kwRP, respectively). Based on the retention factor (log kwRP) and slope of the linear curve (S) the isocratic parameter (φ0) was calculated. Obtained retention factors were correlated with experimental log BB values for the group of examined compounds. High correlations were obtained between logarithm of biopartitioning micellar chromatography (BMC) retention factor and effective permeability (r(log kBMC/log BB): 0.77), while for RP-HPLC system the correlations were lower (r(log kwRP/log BB): 0.58; r(S/log BB): -0.50; r(φ0/Pe): 0.61). Based on the log kBMC retention data and calculated molecular parameters of the examined compounds, quantitative structure-permeability relationship (QSPR) models were developed using partial least squares, stepwise multiple linear regression, support vector machine and artificial neural network methodologies. A high degree of structural diversity of the analysed IRs/α-ARs ligands and CNS drugs provides wide applicability domain of the QSPR models for estimation of blood-brain barrier penetration of the related compounds.

  10. Cooling simulation of plastic injection molding

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Analyses the cooling of mold and plastic part during injectionmolding and the continued cooling of plastic part after being ejected from mold using the heat transfer theory and Boundary Element Method (BEM) to predict the temperature distribution in both mold and plastic part,and presents the experiments carried out with plates of ABS (Acrylonitrile-Butadiene-Styrene) to verify the validity of the cooling analysis software used to simulate the temperature distribution in ABS plate parts, and concludes that the analysis software agree qualitatively well with actual experimental findings.

  11. Biodegradability of plastics.

    Science.gov (United States)

    Tokiwa, Yutaka; Calabia, Buenaventurada P; Ugwu, Charles U; Aiba, Seiichi

    2009-08-26

    Plastic is a broad name given to different polymers with high molecular weight, which can be degraded by various processes. However, considering their abundance in the environment and their specificity in attacking plastics, biodegradation of plastics by microorganisms and enzymes seems to be the most effective process. When plastics are used as substrates for microorganisms, evaluation of their biodegradability should not only be based on their chemical structure, but also on their physical properties (melting point, glass transition temperature, crystallinity, storage modulus etc.). In this review, microbial and enzymatic biodegradation of plastics and some factors that affect their biodegradability are discussed.

  12. 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......, plastics from WEEE is chosen as a Nordic case study. The project aims to propose a number of improvements for this value chain together with representatives from Nordic stakeholders. Based on the experiences made, a guide for other plastic value chains shall be developed....

  13. Biodegradability of Plastics

    Directory of Open Access Journals (Sweden)

    Yutaka Tokiwa

    2009-08-01

    Full Text Available Plastic is a broad name given to different polymers with high molecular weight, which can be degraded by various processes. However, considering their abundance in the environment and their specificity in attacking plastics, biodegradation of plastics by microorganisms and enzymes seems to be the most effective process. When plastics are used as substrates for microorganisms, evaluation of their biodegradability should not only be based on their chemical structure, but also on their physical properties (melting point, glass transition temperature, crystallinity, storage modulus etc.. In this review, microbial and enzymatic biodegradation of plastics and some factors that affect their biodegradability are discussed.

  14. Journal of CHINA PLASTICS

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    Journal of CHINA PLASTICS was authorized and approved by The State Committee of Science and Technology of China and The Bureau of News Press of China, and published by The China Plastics Processing Industry Association,Beijing Technology and Business University and The Institute of Plastics Processing and Application of Light Industry, distributed worldwide. Since its birth in 1987, CHINA PLASTICS has become a leading magazine in plastics industry in China, a national Chinese core journal and journal of Chinese scientific and technological article statistics. It is covered by CA.

  15. Development of a definition for Rapid Progression (RP) of renal function in HIV-positive persons

    DEFF Research Database (Denmark)

    Kamara, David A; Nielsen, Lene Ryom; Ross, Michael

    2014-01-01

    No consensus exists on how to define abnormally rapid deterioration in renal function (Rapid Progression, RP). We developed an operational definition of RP in HIV-positive persons with baseline estimated glomerular filtration rate (eGFR) >90ml/min/1.73m2 (using Cockcroft Gault) in the Data...

  16. 76 FR 35006 - Recovery Policy RP9525.16, Research-Related Equipment and Furnishings

    Science.gov (United States)

    2011-06-15

    ... SECURITY Federal Emergency Management Agency Recovery Policy RP9525.16, Research-Related Equipment and... document provides notice of the availability of the final policy RP9525.16, Research-related Equipment and... comments on August 13, 2010. DATES: This policy is effective May 3, 2011. ADDRESSES: This final policy...

  17. 75 FR 49506 - Recovery Policy, RP9525.16, Research-Related Equipment and Furnishings

    Science.gov (United States)

    2010-08-13

    ... SECURITY Federal Emergency Management Agency Recovery Policy, RP9525.16, Research-Related Equipment and... RP9525.16 Research-related Equipment and Furnishings. This is an existing policy that is scheduled for.... This policy identifies the expenses associated with disaster-damaged research-related equipment...

  18. A practical interconnection network RP(k) and its routing algorithms

    Institute of Scientific and Technical Information of China (English)

    刘方爱; 刘志勇; 乔香珍

    2001-01-01

    Based on Petersen graph, a new interconnection network, the RP(k) network, is developed and the properties of the RP(k) network are investigated. The diameter of the RP(k) network is [ k/2] + 2 and its degree is 5. We prove that the diameter of the RP(k) network is much smaller than that of the 2-D Torus network when the number of nodes in interconnection networks is less than or equal to 300. In order to analyze the communication performance in a group of nodes, we propose the concepts of the optimal node groups and the diameter of the optimal node groups. We also show that the diameter of the optimal node groups in the RP(k) network is less than that in the 2-D Torus network. Especially when the number of nodes in an optimal node group is between 6 and 100, the diameter of the optimal node groups in the RP(k) network is half of that in the 2-D Torus network. Furthermore based on the RP(k) network we design a set of routing algorithms which are point-to-point routing, permutation routing, one-to-all routing and all-to-all routing. Their communication efficiencies are [k/2] + 2, k + 5, [k/2] + 2, and k + 5 respectively. The RP(k) network and the routing algorithms can provide efficient communication means for parallel and distributed computer system.

  19. 77 FR 40626 - RP9580.210, Personal Assistance Services in Shelters Fact Sheet

    Science.gov (United States)

    2012-07-10

    ... SECURITY Federal Emergency Management Agency RP9580.210, Personal Assistance Services in Shelters Fact... comments. SUMMARY: The Federal Emergency Management Agency (FEMA) is accepting comments on Recovery Fact Sheet RP9580.210, Personal Assistance Services in Shelters. The purpose of this new fact sheet is to...

  20. The inhibitory activity of ginsenoside Rp4 in adenosine diphosphate-induced platelet aggregation

    Directory of Open Access Journals (Sweden)

    Young-Min Son

    2017-01-01

    Conclusion: G-Rp4 significantly inhibited ADP-induced platelet aggregation and this is mediated via modulating the intracellular signaling molecules. These results indicate that G-Rp4 could be a potential candidate as a therapeutic agent against platelet-related cardiovascular diseases.

  1. RP58 regulates the multipolar-bipolar transition of newborn neurons in the developing cerebral cortex.

    Science.gov (United States)

    Ohtaka-Maruyama, Chiaki; Hirai, Shinobu; Miwa, Akiko; Heng, Julian Ik-Tsen; Shitara, Hiroshi; Ishii, Rie; Taya, Choji; Kawano, Hitoshi; Kasai, Masataka; Nakajima, Kazunori; Okado, Haruo

    2013-02-21

    Accumulating evidence suggests that many brain diseases are associated with defects in neuronal migration, suggesting that this step of neurogenesis is critical for brain organization. However, the molecular mechanisms underlying neuronal migration remain largely unknown. Here, we identified the zinc-finger transcriptional repressor RP58 as a key regulator of neuronal migration via multipolar-to-bipolar transition. RP58(-/-) neurons exhibited severe defects in the formation of leading processes and never shifted to the locomotion mode. Cre-mediated deletion of RP58 using in utero electroporation in RP58(flox/flox) mice revealed that RP58 functions in cell-autonomous multipolar-to-bipolar transition, independent of cell-cycle exit. Finally, we found that RP58 represses Ngn2 transcription to regulate the Ngn2-Rnd2 pathway; Ngn2 knockdown rescued migration defects of the RP58(-/-) neurons. Our findings highlight the critical role of RP58 in multipolar-to-bipolar transition via suppression of the Ngn2-Rnd2 pathway in the developing cerebral cortex.

  2. A small potassium current in AgRP/NPY neurons regulates feeding behavior and enery metabolism

    Science.gov (United States)

    Neurons that co-express agouti-related peptide (AgRP) and neuropeptide Y (NPY) are indispensable for normal feeding behavior. Firing activities of AgRP/NPY neurons are dynamically regulated by energy status and coordinate appropriate feeding behavior to meet nutritional demands. However, intrinsic m...

  3. Ways of Viewing Pictorial Plasticity

    Directory of Open Access Journals (Sweden)

    Maarten W. A. Wijntjes

    2017-03-01

    Full Text Available The plastic effect is historically used to denote various forms of stereopsis. The vivid impression of depth often associated with binocular stereopsis can also be achieved in other ways, for example, using a synopter. Accounts of this go back over a hundred years. These ways of viewing all aim to diminish sensorial evidence that the picture is physically flat. Although various viewing modes have been proposed in the literature, their effects have never been compared. In the current study, we compared three viewing modes: monocular blur, synoptic viewing, and free viewing (using a placebo synopter. By designing a physical embodiment that was indistinguishable for the three experimental conditions, we kept observers naïve with respect to the differences between them; 197 observers participated in an experiment where the three viewing modes were compared by performing a rating task. Results indicate that synoptic viewing causes the largest plastic effect. Monocular blur scores lower than synoptic viewing but is still rated significantly higher than the baseline conditions. The results strengthen the idea that synoptic viewing is not due to a placebo effect. Furthermore, monocular blur has been verified for the first time as a way of experiencing the plastic effect, although the effect is smaller than synoptic viewing. We discuss the results with respect to the theoretical basis for the plastic effect. We show that current theories are not described with sufficient details to explain the differences we found.

  4. 热固性塑料剪切粉碎机腔内流场数值模拟与试验分析%Numerical Simulation and Experimental Analysis of Fluid Field for Thermoset Plastic Shear Shredder Cavity

    Institute of Scientific and Technical Information of China (English)

    刘志峰; 赵建; 吴仲伟; 石磊

    2012-01-01

    超细粉碎是实现热固性塑料高效回收的前提,为了研究粉碎机腔内的流场变化对粉碎效果的影响,简化了粉碎机腔的内部模型,并忽略其颗粒的影响,采用RNG k—ε双方程湍流模型和SIMPLER算法求解气相的N—S方程,针对粉碎机腔内的刀齿结构、内壁结构及粉碎机转速的几种不同方案,分析了数值模拟获得的粉碎机腔内的压力场和速度场,确定三螺旋刀齿和阶梯内壁结构作为试验专机设计方案进行试验,结果表明:物料在该条件下的粉碎能达到很小的粒径,粉碎过程中生成了自由基团,取样观察发现了团聚现象.%Achieving thermosetting plastics ultra-fine grinding is the prerequisite for efficient recycling. In order to study the flow field patterns of thermosetting plastics during the process of crushing, through simplifying the internal cavity grinder model, ignoring the impact of particles, using the theory of computational fluid dynamics, and applying model of RNG k - ε turbulence and the algorithm of SIMPLER the N-S equations of gas was solved,In connection with several different options of cutter grinder cavity structure, wall structure, and mill speed, the pressure field and velocity field of the cutting shredders were analyzed via numerical simulation, and making the triple helix cutter and ladder wall structure as an experimental test plane. The results show that material can get very small particle under this condition. Tests show that material can get very small particle under the condition and it also generates the free basic particle during the process of grinding, meanwhile the condition of milling group during the process of sampling is found.

  5. Challenges in plastics recycling

    DEFF Research Database (Denmark)

    Pivnenko, Kostyantyn; Jakobsen, L. G.; Eriksen, Marie Kampmann

    2015-01-01

    Recycling of waste plastics still remains a challenging area in the waste management sector. The current and potential goals proposed on EU or regional levels are difficult to achieve, and even to partially fullfil them the improvements in collection and sorting should be considerable. A study...... was undertaken to investigate the factors affecting quality in plastics recycling. The preliminary results showed factors primarily influencing quality of plastics recycling to be polymer cross contamination, presence of additives, non-polymer impurities, and polymer degradation. Deprivation of plastics quality......, with respect to recycling, has been shown to happen throughout the plastics value chain, but steps where improvements may happen have been preliminary identified. Example of Cr in plastic samples analysed showed potential spreading and accumulation of chemicals ending up in the waste plastics. In order...

  6. Glassy metallic plastics

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    This paper reports a class of bulk metallic glass including Ce-, LaCe-, CaLi-, Yb-, and Sr-based metallic glasses, which are regarded as glassy metallic plastics because they combine some unique properties of both plastics and metallic alloys. These glassy metallic plastics have very low glass transition temperature (Tg~25oC to 150oC) and low Young’s modulus (~20 GPa to 35 GPa). Similar to glassy plastics, these metallic plastics show excellent plastic-like deformability on macro-, micro- and even nano-scale in their supercooled liquid range and can be processed, such as elongated, compressed, bent, and imprinted at low temperatures, in hot water for instance. Under ambient conditions, they display such metallic properties as high thermal and electric conductivities and excellent mechanical properties and other unique properties. The metallic plastics have potential applications and are also a model system for studying issues in glass physics.

  7. Contrasting evolutionary patterns of the Rp1 resistance gene family in different species of Poaceae.

    Science.gov (United States)

    Luo, Sha; Peng, Junhua; Li, Kunpeng; Wang, Min; Kuang, Hanhui

    2011-01-01

    Disease-resistance genes (R-genes) in plants show complex evolutionary patterns. We investigated the evolution of the Rp1 R-gene family in Poaceae, and 409 Rp1 fragments were sequenced from 21 species. Our data showed that the common ancestor of Poaceae had two Rp1 loci, but the number of Rp1 locus in extant species varies from one to five. Some wheat and Zea genotypes have dozens of Rp1 homologues in striking contrast to one or two copies in Brachypodium distachyon. The large number of diverse Rp1 homologues in Zea was the result of duplications followed by extensive sequence exchanges among paralogues, and all genes in maize have evolved in a pattern of Type I R-genes. The high frequency of sequence exchanges did not cause concerted evolution in Zea species, but concerted evolution was obvious between Rp1 homologues from genera Zea and Sorghum. Differentiation of Type I and Type II Rp1 homologues was observed in Oryza species, likely occurred in their common ancestor. One member (Type II R-gene) in the Oryza Rp1 cluster did not change sequences with its paralogues, whereas the other paralogues (Type I R-genes) had frequent sequence exchanges. The functional Pi37 resistance gene in rice was generated through an unequal crossover between two neighboring paralogues followed by four point mutations. The Rp1 homologues in wheat and barley were most divergent, probably due to lack of sequence exchanges among them. Our results shed more light on R-gene evolution, particularly on the differentiation of Type I and Type II R-genes.

  8. The embedding of rings and meshes into RP(k)networks

    Institute of Scientific and Technical Information of China (English)

    LIU Fang'ai; LIU Zhiyong; ZHANG Yongsheng

    2004-01-01

    This paper first investigates the topological properties of RP(k) networks.Then focusing on the embedding of rings and 2-D meshes into the RP(k) network, it is proved that the RP(k) network is a Hamiltonian graph and the ring with 10*k nodes can be embedded into the RP(k) network with load, expansion, dilation and congestion all equal to 1. If there exists a faulty node on each slice in the RP(k) network, throwing off the faulty nodes, the RP-1(k) network is obtained. It is also proved that there exists a Hamiltonain cycle in the RP-1(k) network. So the ring with 9*k nodes can be embedded into the RP1 (k) network. After that, we discuss the embedding of a 2-D mesh, M1(a, b), into the RP(k) network. By defining the sequence-column-order mapping, the snake-like-column-order mapping and the shortest path mapping, we obtain two ways of embedding a 2-D mesh into the RP(k) network. The performances of the embedding are as follows. In the snake-like-column-order mapping, the dilations are 1, 2, 3, 3 and 2 and the congestion are 1, 3, 4, 5 and 3 respectively when a is equal to 1, 2, 3, 4 and 5. In the sequencecolumn-order mapping, the dilation is equal to 3 and the congestion is equal to 6 when a is between 6 and 9. The dilation is equal to 「a/10」+2 and the congestion is equal to max{「a/10」+1, 6} when a >10. As a special case, the four parameters are also equal to 1 when a is equal to 10.

  9. Dynamic impact of temporal context of Ca²⁺ signals on inhibitory synaptic plasticity.

    Science.gov (United States)

    Kawaguchi, Shin-Ya; Nagasaki, Nobuhiro; Hirano, Tomoo

    2011-01-01

    Neuronal activity-dependent synaptic plasticity, a basis for learning and memory, is tightly correlated with the pattern of increase in intracellular Ca(2+) concentration ([Ca(2+)](i)). Here, using combined application of electrophysiological experiments and systems biological simulation, we show that such a correlation dynamically changes depending on the context of [Ca(2+)](i) increase. In a cerebellar Purkinje cell, long-term potentiation of inhibitory GABA(A) receptor responsiveness (called rebound potentiation; RP) was induced by [Ca(2+)](i) increase in a temporally integrative manner through sustained activation of Ca(2+)/calmodulin-dependent protein kinase II (CaMKII). However, the RP establishment was canceled by coupling of two patterns of RP-inducing [Ca(2+)](i) increase depending on the temporal sequence. Negative feedback signaling by phospho-Thr305/306 CaMKII detected the [Ca(2+)](i) context, and assisted the feedforward inhibition of CaMKII through PDE1, resulting in the RP impairment. The [Ca(2+)](i) context-dependent dynamic regulation of synaptic plasticity might contribute to the temporal refinement of information flow in neuronal networks.

  10. Strain rate dependence in plasticized and un-plasticized PVC

    Directory of Open Access Journals (Sweden)

    Siviour C.R.

    2012-08-01

    Full Text Available An experimental and analytical investigation has been made into the mechanical behaviour of two poly (vinyl chloride (PVC polymers – an un-plasticized PVC and a diisononyl phthalate (DINP-plasticized PVC. Measurements of the compressive stress-strain behaviour of the PVCs at strain rates ranging from 10−3 to 103s−1 and temperatures from − 60 to 100∘C are presented. Dynamic Mechanical Analysis was also performed in order to understand the material transitions observed in compression testing as the strain rate is increased. This investigation develops a better understanding of the interplay between the temperature dependence and rate dependence of polymers, with a focus on locating the temperature and rate-dependent material transitions that occur during high rate testing.

  11. Strain rate dependence in plasticized and un-plasticized PVC

    Science.gov (United States)

    Kendall, M. J.; Siviour, C. R.

    2012-08-01

    An experimental and analytical investigation has been made into the mechanical behaviour of two poly (vinyl chloride) (PVC) polymers - an un-plasticized PVC and a diisononyl phthalate (DINP)-plasticized PVC. Measurements of the compressive stress-strain behaviour of the PVCs at strain rates ranging from 10-3 to 103s-1 and temperatures from - 60 to 100∘C are presented. Dynamic Mechanical Analysis was also performed in order to understand the material transitions observed in compression testing as the strain rate is increased. This investigation develops a better understanding of the interplay between the temperature dependence and rate dependence of polymers, with a focus on locating the temperature and rate-dependent material transitions that occur during high rate testing.

  12. Opposing Effects of Neuronal Activity on Structural Plasticity.

    Science.gov (United States)

    Fauth, Michael; Tetzlaff, Christian

    2016-01-01

    The connectivity of the brain is continuously adjusted to new environmental influences by several activity-dependent adaptive processes. The most investigated adaptive mechanism is activity-dependent functional or synaptic plasticity regulating the transmission efficacy of existing synapses. Another important but less prominently discussed adaptive process is structural plasticity, which changes the connectivity by the formation and deletion of synapses. In this review, we show, based on experimental evidence, that structural plasticity can be classified similar to synaptic plasticity into two categories: (i) Hebbian structural plasticity, which leads to an increase (decrease) of the number of synapses during phases of high (low) neuronal activity and (ii) homeostatic structural plasticity, which balances these changes by removing and adding synapses. Furthermore, based on experimental and theoretical insights, we argue that each type of structural plasticity fulfills a different function. While Hebbian structural changes enhance memory lifetime, storage capacity, and memory robustness, homeostatic structural plasticity self-organizes the connectivity of the neural network to assure stability. However, the link between functional synaptic and structural plasticity as well as the detailed interactions between Hebbian and homeostatic structural plasticity are more complex. This implies even richer dynamics requiring further experimental and theoretical investigations.

  13. Study on the Plastic Bottle Recycling Based on Evolution Tree for Technical System

    OpenAIRE

    Yuedong Xiong; Huadong Huang

    2014-01-01

    Technical system theory of evolution tree was used in the study of the plastic bottle recycling, and established the evolutionary line of plastic bottle recycling on the basis of the analysis of plastic bottle recycling recovery evolution tree, and summed up a new smart plastic bottle recycling program. The new recovery recovers and smashes the plastic bottles through technical system, and communicates with users through automatically reward system and rewards the latter. The experimental pro...

  14. The plastic compressibility of 7075-T651 aluminum-alloy plate

    Science.gov (United States)

    Freed, A. D.; Sandor, B. I.

    1986-01-01

    The change in volume, and therefore the change in mass density, of an aluminum alloy was measured in uniaxial tension using clip-on extensometers. The experimental data do not agree with the assumption of plastic incompressibility found in the classical theories of plasticity. In fact, the elastic and plastic volume changes are of the same order of magnitude. Plastic anisotropy is thought to be the prime cause of this plastic compressibility.

  15. Isomer and decay studies for the rp process at IGISOL

    Energy Technology Data Exchange (ETDEWEB)

    Kankainen, A.; Elomaa, V.V.; Eronen, T.; Hakala, J.; Jokinen, A.; Karvonen, P.; Reponen, M.; Rissanen, J.; Saastamoinen, A.; Weber, C.; Aeystoe, J. [University of Jyvaeskylae, Department of Physics, Jyvaeskylae (Finland); Novikov, Yu.N.; Batist, L. [Petersburg Nuclear Physics Institute, Gatchina (Russian Federation); Oinonen, M. [University of Helsinki, Dating Laboratory, Helsinki (Finland); Vorobjev, G. [Gesellschaft fuer Schwerionenforschung mbH, Darmstadt (Germany)

    2012-04-15

    This article reviews the decay studies of neutron-deficient nuclei within the mass region A=56-100 performed at the Ion-Guide Isotope Separator On-Line (IGISOL) facility in the University of Jyvaeskylae over last 25 years. Development from He-jet measurements to on-line mass spectrometry, and eventually to atomic mass measurements and post-trap spectroscopy at IGISOL, has yielded studies of around 100 neutron-deficient nuclei over the years. The studies form a solid foundation to astrophysical rp -process path modelling. The focus is on isomers studied either via spectroscopy or via Penning-trap mass measurements. The review is complemented with recent results on the ground and isomeric states of {sup 90}Tc. The excitation energy of the low-spin isomer in {sup 90}Tc has been measured as E{sub x}=144.1(17) keV with JYFLTRAP double Penning trap and the ground state of {sup 90}Tc has been confirmed to be the (8{sup +}) state with a half-life of T{sub 1/2}=49.2(4) s. Finally, the mass-excess results for the spin-gap isomers {sup 53}Co{sup m} and {sup 95}Pd{sup m} and implications from the JYFLTRAP mass measurements for the (21{sup +}) isomer in {sup 94}Ag are discussed. (orig.)

  16. Gene augmentation for adRP mutations in RHO.

    Science.gov (United States)

    Lewin, Alfred S; Rossmiller, Brian; Mao, Haoyu

    2014-07-18

    Mutations in the gene for rhodopsin, RHO, cause autosomal dominant retinitis pigmentosa, a disease characterized by death of rod photoreceptor cells. At the end stage, when most rods are gone, cones die too, taking central vision with them. One goal of gene therapy, therefore, is to preserve central vision by promoting rod survival in the vicinity of the macula. Dominance in RHO mutations is associated with two phenomena: interference with the function of normal rhodopsin and intrinsic toxicity of the mutant protein. In the case of interference, increased production of the wild-type protein may be therapeutic, but in the case of toxicity, suppression of the mutant protein may also be needed. RHO augmentation has made use of advances in gene delivery to the retina using adeno-associated virus (AAV). Several strategies have been developed for suppression of rhodopsin expression, but because of the heterogeneity of RHO mutations they are not specific for the mutant allele: They suppress both mutant and wild-type RHO. Experiments in autosomal dominant retinitis pigmentosa (adRP) mouse models suggest that both RHO augmentation and supplementation plus suppression preserve the survival of rod cells. Copyright © 2014 Cold Spring Harbor Laboratory Press; all rights reserved.

  17. Novel hypophysiotropic AgRP2 neurons and pineal cells revealed by BAC transgenesis in zebrafish

    Science.gov (United States)

    Shainer, Inbal; Buchshtab, Adi; Hawkins, Thomas A.; Wilson, Stephen W.; Cone, Roger D.; Gothilf, Yoav

    2017-01-01

    The neuropeptide agouti-related protein (AgRP) is expressed in the arcuate nucleus of the mammalian hypothalamus and plays a key role in regulating food consumption and energy homeostasis. Fish express two agrp genes in the brain: agrp1, considered functionally homologous with the mammalian AgRP, and agrp2. The role of agrp2 and its relationship to agrp1 are not fully understood. Utilizing BAC transgenesis, we generated transgenic zebrafish in which agrp1- and agrp2-expressing cells can be visualized and manipulated. By characterizing these transgenic lines, we showed that agrp1-expressing neurons are located in the ventral periventricular hypothalamus (the equivalent of the mammalian arcuate nucleus), projecting throughout the hypothalamus and towards the preoptic area. The agrp2 gene was expressed in the pineal gland in a previously uncharacterized subgroup of cells. Additionally, agrp2 was expressed in a small group of neurons in the preoptic area that project directly towards the pituitary and form an interface with the pituitary vasculature, suggesting that preoptic AgRP2 neurons are hypophysiotropic. We showed that direct synaptic connection can exist between AgRP1 and AgRP2 neurons in the hypothalamus, suggesting communication and coordination between AgRP1 and AgRP2 neurons and, therefore, probably also between the processes they regulate. PMID:28317906

  18. A Small Potassium Current in AgRP/NPY Neurons Regulates Feeding Behavior and Energy Metabolism

    Directory of Open Access Journals (Sweden)

    Yanlin He

    2016-11-01

    Full Text Available Neurons that co-express agouti-related peptide (AgRP and neuropeptide Y (NPY are indispensable for normal feeding behavior. Firing activities of AgRP/NPY neurons are dynamically regulated by energy status and coordinate appropriate feeding behavior to meet nutritional demands. However, intrinsic mechanisms that regulate AgRP/NPY neural activities during the fed-to-fasted transition are not fully understood. We found that AgRP/NPY neurons in satiated mice express high levels of the small-conductance calcium-activated potassium channel 3 (SK3 and are inhibited by SK3-mediated potassium currents; on the other hand, food deprivation suppresses SK3 expression in AgRP/NPY neurons, and the decreased SK3-mediated currents contribute to fasting-induced activation of these neurons. Genetic mutation of SK3 specifically in AgRP/NPY neurons leads to increased sensitivity to diet-induced obesity, associated with chronic hyperphagia and decreased energy expenditure. Our results identify SK3 as a key intrinsic mediator that coordinates nutritional status with AgRP/NPY neural activities and animals’ feeding behavior and energy metabolism.

  19. Ion radiation damage in plastic detectors

    Energy Technology Data Exchange (ETDEWEB)

    Balcazar, M

    2006-07-01

    Plastic detectors are widely used for particle identification, micro pore and nano pore technology, neutron, gamma, radon and electron dosimeters. For some applications, plastic detectors have unique advantages among electronic detectors as 4 solid angles for ion identification in nuclear and cosmic ray physics; low-cost for massive use in indoors radon and neutron dosimeters; wide dose-range response for gamma and electron dosimetry; easy to use detectors in active geological faults in prospecting geothermal energy etc. There is a grate diversity of plastic detectors, which further improves their use in a particular application. However, the comparison test between different kinds of plastics can be time consuming, being therefore necessary to have methods for rapidly assessing plastic detectors properties. This invited talk deals in the first part with overview applications in Mexico of plastic detectors mentioned in the first paragraph. In the second part presents a general experimental relationship between the diameter-grow of positive ions tracks in several plastics for light ions, that allow to compare their energy resolution and to predict the track diameter of isotopes beams, as well as to predict the uniformity of micro pores. The formation of Nano pores produced by {sup 238} U ions is also discussed. (Author)

  20. Plastic Pollution from Ships

    OpenAIRE

    Čulin, Jelena; Bielić, Toni

    2016-01-01

    The environmental impact of shipping on marine environment includes discharge of garbage. Plastic litter is of particular concern due to abundance, resistance to degradation and detrimental effect on marine biota. According to recently published studies, a further research is required to assess human health risk. Monitoring data indicate that despite banning plastic disposal at sea, shipping is still a source of plastic pollution. Some of the measures to combat the problem are discussed.

  1. File list: Pol.Emb.05.RpII215.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Pol.Emb.05.RpII215.AllCell dm3 RNA polymerase RpII215 Embryo SRX859013,SRX859009,SR...X859007,SRX859011 http://dbarchive.biosciencedbc.jp/kyushu-u/dm3/assembled/Pol.Emb.05.RpII215.AllCell.bed ...

  2. Handbook of Plastic Welding

    DEFF Research Database (Denmark)

    Islam, Aminul

    The purpose of this document is to summarize the information about the laser welding of plastic. Laser welding is a matured process nevertheless laser welding of micro dimensional plastic parts is still a big challenge. This report collects the latest information about the laser welding of plasti...... as a knowledge handbook for laser welding of plastic components. This document should provide the information for all aspects of plastic laser welding and help the design engineers to take all critical issues into consideration from the very beginning of the design phase....

  3. Plastics and health risks.

    Science.gov (United States)

    Halden, Rolf U

    2010-01-01

    By 2010, the worldwide annual production of plastics will surpass 300 million tons. Plastics are indispensable materials in modern society, and many products manufactured from plastics are a boon to public health (e.g., disposable syringes, intravenous bags). However, plastics also pose health risks. Of principal concern are endocrine-disrupting properties, as triggered for example by bisphenol A and di-(2-ethylhexyl) phthalate (DEHP). Opinions on the safety of plastics vary widely, and despite more than five decades of research, scientific consensus on product safety is still elusive. This literature review summarizes information from more than 120 peer-reviewed publications on health effects of plastics and plasticizers in lab animals and humans. It examines problematic exposures of susceptible populations and also briefly summarizes adverse environmental impacts from plastic pollution. Ongoing efforts to steer human society toward resource conservation and sustainable consumption are discussed, including the concept of the 5 Rs--i.e., reduce, reuse, recycle, rethink, restrain--for minimizing pre- and postnatal exposures to potentially harmful components of plastics.

  4. Synaptic Plasticity and Nociception

    Institute of Scientific and Technical Information of China (English)

    ChenJianguo

    2004-01-01

    Synaptic plasticity is one of the fields that progresses rapidly and has a lot of success in neuroscience. The two major types of synaptie plasticity: long-term potentiation ( LTP and long-term depression (LTD are thought to be the cellular mochanisms of learning and memory. Recently, accumulating evidence suggests that, besides serving as a cellular model for learning and memory, the synaptic plasticity involves in other physiological or pathophysiological processes, such as the perception of pain and the regulation of cardiovascular system. This minireview will focus on the relationship between synaptic plasticity and nociception.

  5. RP-HPLC法测定舒必利片的含量%Determination of Sulpiride Tablets by RP-HPLC

    Institute of Scientific and Technical Information of China (English)

    李小燕

    2003-01-01

    @@ 舒必利即是一种新型抗精神病药物,又具有强力抗呕吐作用.可用于治疗呕吐、精神分裂症及幻觉妄想症、官能性抑郁症等.其含量测定方法有紫外分光光度法[1,2]、高氯酸-电位滴定法[3]、荧光光度法[4]、示波极谱法[5]、比色法[6]、高效液相色谱-荧光测定法[7]等.本文采用RP-HPLC法测定了舒必利片的含量,并与紫外分光光度法[1]进行了对比,结果满意.本法操作简便、快速、准确.

  6. Evaluation of neutron dose and gamma dose at thermal facility of Peruvian research reactor RP-10; Evaluacion de la dosis gamma y de neutrones en la facilidad termica del reactor peruano de investigacion RP-10

    Energy Technology Data Exchange (ETDEWEB)

    Gomez, Javier; Miranda, Hector; Aparicio, Claudia; Lazaro, Gerardo [Instituto Peruano de Energia Nuclear (IPEN), Lima (Peru). Dept. de Calculo, Analisis y Seguridad (CASE)]. E-mail: hmcmiranda@hotmail.com; jjgb76@yahoo.com; caparicio@scientist.com; glazaro@ipen.gob.pe; Zuniga, Agustin [Instituto Peruano de Energia Nuclear (IPEN), Lima (Peru). Direccion General de Instalaciones (DGI)]. E-mail: azuniga@ipen.gob.pe

    2005-07-01

    One of main lines of work in the Peruvian nuclear reactor RP-10, is a complex systems simulation by mean of Monte Carlo technique, oriented in particular to characterization of irradiation facilities. In this work it is presented the comparison of experimental measurements, based in measure of thermal, epithermal and fast neutron flux distribution, neutron dose and gamma dose at thermal facility of RP-10, with the MCNP4B compute code, being observed a good agreement between both results. The neutron flux measures were carried out by irradiation of gold, indium and nickel metallic monitors; then it were measured the activities using a gamma spectrometry chain based on a hyperpure germanium (HPGe) detector. With these results the neutron dose was determined, and it was also measured, using a equipment based on a boron trifluoride detector (BF3, NRC-RemRad). A device based on Geiger Mueller detector (FAG-FH40FE) was used for the gamma dose rate measurement. Finally there were measured both gamma and neutron dose rate using TLD-600 and TLD-700 thermoluminescent dosimeters, which were previously characterized. (author)

  7. Plasticity predicts evolution in a marine alga.

    Science.gov (United States)

    Schaum, C Elisa; Collins, Sinéad

    2014-10-22

    Under global change, populations have four possible responses: 'migrate, acclimate, adapt or die' (Gienapp et al. 2008 Climate change and evolution: disentangling environmental and genetic response. Mol. Ecol. 17, 167-178. (doi:10.1111/j.1365-294X.2007.03413.x)). The challenge is to predict how much migration, acclimatization or adaptation populations are capable of. We have previously shown that populations from more variable environments are more plastic (Schaum et al. 2013 Variation in plastic responses of a globally distributed picoplankton species to ocean acidification. Nature 3, 298-230. (doi:10.1038/nclimate1774)), and here we use experimental evolution with a marine microbe to learn that plastic responses predict the extent of adaptation in the face of elevated partial pressure of CO2 (pCO2). Specifically, plastic populations evolve more, and plastic responses in traits other than growth can predict changes in growth in a marine microbe. The relationship between plasticity and evolution is strongest when populations evolve in fluctuating environments, which favour the evolution and maintenance of plasticity. Strikingly, plasticity predicts the extent, but not direction of phenotypic evolution. The plastic response to elevated pCO2 in green algae is to increase cell division rates, but the evolutionary response here is to decrease cell division rates over 400 generations until cells are dividing at the same rate their ancestors did in ambient CO2. Slow-growing cells have higher mitochondrial potential and withstand further environmental change better than faster growing cells. Based on this, we hypothesize that slow growth is adaptive under CO2 enrichment when associated with the production of higher quality daughter cells.

  8. Influence of pH on retention in linear organic modifier gradient RP HPLC.

    Science.gov (United States)

    Wiczling, Paweł; Kaliszan, Roman

    2008-10-15

    The purpose of this work was to examine the influence of pH on retention of analytes during the linear organic modifier gradient in RP HPLC. We started from the general theory of combined pH/organic modifier gradient and provided an explicit however approximate solution relating gradient retention time and the pH of the eluent. The accuracy of the proposed model was tested by its ability to describe an experimental data set that comprised retention times for a series of monoprotic acids and bases obtained at different pH and for different gradient durations. The basic analytical properties of the equation relating retention time and pH were determined, such as the inflection point and range of retention times. The use of the pH at inflection point as a measure of p K a was discussed and compared to the chromatographic p K a obtained by a fitting to the proposed model. In conclusion, the work provides theoretical results that augment the knowledge on the impact of pH on the gradient retention.

  9. β-Decay Study of the rp-Process Nucleus ^96Cd

    Science.gov (United States)

    Becerril, Ana; Amthor, A.; Baumann, T.; Bazin, D.; Crawford, H.; Estrade, A.; Gade, A.; Ginter, T.; Guess, C.; Hausmann, M.; Hitt, G.; Lorusso, G.; Mantica, P.; Matos, M.; Meharchand, R.; Minamisono, K.; Montes, F.; Pereira, J.; Perdikakis, G.; Pinter, J.; Portillo, M.; Schatz, H.; Smith, K.; Stoker, J.; Zegers, R.

    2008-10-01

    The half-life of ^96Cd, one of the major waiting points along the reaction path of the rp-process [1] has been measured at NSCL. Nuclei of interest were produced by fragmentation of a 120 MeV/u ^112Sn primary beam on a Be target and selected with the A1900 fragment separator in conjunction with the RF Fragment Separator [2]. The experimental setup, which consisted on the NSCL β-Counting System [3] and the Segmented Germanium Array [4], permitted the correlation of implants and decays as well as the detection of both prompt and β-delayed γ-rays from implanted ions. Details of the experiment and results will be presented and their implications discussed. [1] H. Schatz et al., Phys. Rep. 294, 167 1998 [2] D. Gorelov et al. PAC 2005, Knoxville, TN, May 16-20 [3] J. Prisciandaro et al., NIM A 505, 140 2003 [4] W. Mueller et al., NIM A 466, 492 2001

  10. Time Delay for the Initiation of an Emergency Shutdown at the Peruvian Nuclear Reactor RP-10

    Energy Technology Data Exchange (ETDEWEB)

    Ramon, A.; Ovalle, E.; Canaza, D.; Salazar, A.; Zapata, A.; Felix, J.; Arrieta, R.; Vela, M. [Instituto Peruano de Energia Nuclear, Av. Canada 1470, San Borja, Lima (Peru)

    2008-07-01

    In this paper we show the measurement of the time delay for the initiation of an emergency shutdown state at the RP-10 Reactor. This time delay is the one corresponding to the delay between the detection of a signal of any fixed limit and the start of a protective action to get the reactor in a safety state. The experimental method used is based on monitoring two signals in an oscilloscope, one signal is the elected initiate event and the other is the de-energizing of electromagnets of the security bars. The time delay for each safety and control rods, was measured for seven energizing current values in a range of 36 - 52 mA. The results showed that the minimum value is (84 {+-} 1.26) ms and the maximum is (108 {+-} 1.60) ms. In all cases it is noted that, the delay time is less than the limit values prefixed down in the reactor safety report. (authors)

  11. Evaluation of operational incidents in the research reactor RP-10 according to scale INES; Evaluacion de incidentes operacionales en el reactor de investigacion RP-10 segun escala INES

    Energy Technology Data Exchange (ETDEWEB)

    Arrieta, Rolando W.B.; Vela Mora, Mariano, E-mail: rarrieta@ipen.gob.pe, E-mail: mvela@ipen.gob.pe [Instituto Peruano de energia Nuclear, Lima (Peru). Dept. de Operacion de Reactores

    2013-07-01

    This report presents the evaluation of the events in 2011 in the RP-10 Nuclear Reactor Nuclear Center Huarangal from the point of view of safety. To classify these events produced is used Scale International Nuclear and Radiological Event Scale (INES) to facilitate a common understanding between the technical community, the media and the general public. From the results we can say that in 2011 all related to security events that occurred in the RP -10 are classified as 'below scale' or no safety significance. (author)

  12. Halos of Plastic

    Institute of Scientific and Technical Information of China (English)

    Maya Reid

    2012-01-01

    The halos that span South Africa's coastline are anything but angelic. Fanning out around four major urban centers-Cape Town, Port Elizabeth, East London and Durban-they are made up of innumerable bits and pieces of plastic. As a form of pollution, their shelflife is unfathomable. Plastic is essentially chemically inactive. It's designed to never break down.

  13. Biodegradation of plastics.

    Science.gov (United States)

    Shimao, M

    2001-06-01

    Widespread studies on the biodegradation of plastics have been carried out in order to overcome the environmental problems associated with synthetic plastic waste. Recent work has included studies of the distribution of synthetic polymer-degrading microorganisms in the environment, the isolation of new microorganisms for biodegradation, the discovery of new degradation enzymes, and the cloning of genes for synthetic polymer-degrading enzymes.

  14. DESIGNERS’ KNOWLEDGE IN PLASTICS

    DEFF Research Database (Denmark)

    Eriksen, Kaare

    2013-01-01

    The Industrial designers’ knowledge in plastics materials and manufacturing principles of polymer products is very important for the innovative strength of the industry, according to a group of Danish plastics manufacturers, design students and practicing industrial designers. These three groups...... answered the first Danish national survey, PD13[1], investigating the importance of industrial designers’ knowledge in plastics and the collaboration between designers and the polymer industry. The plastics industry and the industrial designers collaborate well, but both groups frequently experience...... that the designers’ lack of knowledge concerning polymer materials and manufacturing methods can be problematic or annoying, and design students from most Danish design universities express the need for more contact with the industry and more competencies and tools to handle even simple topics when designing plastic...

  15. Consciousness and neural plasticity

    DEFF Research Database (Denmark)

    In contemporary consciousness studies the phenomenon of neural plasticity has received little attention despite the fact that neural plasticity is of still increased interest in neuroscience. We will, however, argue that neural plasticity could be of great importance to consciousness studies....... If consciousness is related to neural processes it seems, at least prima facie, that the ability of the neural structures to change should be reflected in a theory of this relationship "Neural plasticity" refers to the fact that the brain can change due to its own activity. The brain is not static but rather...... the relation between consciousness and brain functions. If consciousness is connected to specific brain structures (as a function or in identity) what happens to consciousness when those specific underlying structures change? It is therefore possible that the understanding and theories of neural plasticity can...

  16. Common Pitfalls in Exposure and Response Prevention (EX/RP) for OCD

    OpenAIRE

    Gillihan, Seth J.; Williams, Monnica T.; Malcoun, Emily; Yadin, Elna; Edna B. Foa

    2012-01-01

    Obsessive-compulsive disorder (OCD) is a highly debilitating disorder. Fortunately there are treatments that help the majority of OCD sufferers. The behavioral treatment with the most empirical support for its efficacy is exposure and response prevention (EX/RP). Over the years in our supervision meetings and in our clinical practice we have noted a number of relatively common therapist pitfalls that decrease the effectiveness of EX/RP. These pitfalls include not encouraging patients to appro...

  17. Computational implications of cooperative plasticity induction at nearby dendritic sites.

    Science.gov (United States)

    Morita, Kenji

    2009-01-06

    Recent studies have revealed that plasticity is not regulated independently at individual synapses but rather that there is cooperativity or associativity between nearby synapses in the dendritic tree of individual cortical pyramidal cells. Here, I summarize experimental results regarding such cooperative plasticity and its underlying mechanisms and consider their computational implications.

  18. Experimental research on retrieving machine for film residue with whole plastic film mulching on double ridges in arid land%旱地全膜双垄沟残膜回收机的试验研究

    Institute of Scientific and Technical Information of China (English)

    王松林; 敬志臣; 韩正晟; 王波; 戴飞; 高爱民

    2015-01-01

    针对西北旱地全膜双垄沟残膜回收机回收率低的问题,采用正交试验法对残膜回收机的起膜齿齿数、搂膜耙齿齿径、起膜齿入土深度进行研究,并对试验结果进行方差分析,优化了关键部件参数,确定了残膜回收机最佳工作性能参数.即起膜齿齿数为4个,前、中、后搂膜耙齿齿径组合为10-8-6 mm,起膜齿入土深度为50 mm.重复试验结果表明:回收机残膜回收率为93.4%>75%,很好地满足了残膜回收的农艺要求.%Aimed at the problem of lower rate recycling of plastic film collector for whole mulching on double ridges in northwestern arid land,orthogonal test method was used for the study on number of cut-ting film teeth,diameter of collecting film teeth and buried depth of the cutting film teeth.The experimen-tal results were analyzed by variance analysis,and the key component parameters were optimized.The best working performance parameters of the collector were discovered as follows:the number of cutting film teeth was 4,the combination diameter of front,middle and back collecting film teeth was 10-8-6 mm,and the buried depth of the cutting film teeth was 50 mm.The results of replicated tests showed the rate of re-cycling of film was 9 3 .4%>7 5%,which well met the agronomic requirements.

  19. Assembly factors Rpf2 and Rrs1 recruit 5S rRNA and ribosomal proteins rpL5 and rpL11 into nascent ribosomes.

    Science.gov (United States)

    Zhang, Jingyu; Harnpicharnchai, Piyanun; Jakovljevic, Jelena; Tang, Lan; Guo, Yurong; Oeffinger, Marlene; Rout, Michael P; Hiley, Shawna L; Hughes, Timothy; Woolford, John L

    2007-10-15

    More than 170 proteins are necessary for assembly of ribosomes in eukaryotes. However, cofactors that function with each of these proteins, substrates on which they act, and the precise functions of assembly factors--e.g., recruiting other molecules into preribosomes or triggering structural rearrangements of pre-rRNPs--remain mostly unknown. Here we investigated the recruitment of two ribosomal proteins and 5S ribosomal RNA (rRNA) into nascent ribosomes. We identified a ribonucleoprotein neighborhood in preribosomes that contains two yeast ribosome assembly factors, Rpf2 and Rrs1, two ribosomal proteins, rpL5 and rpL11, and 5S rRNA. Interactions between each of these four proteins have been confirmed by binding assays in vitro. These molecules assemble into 90S preribosomal particles containing 35S rRNA precursor (pre-rRNA). Rpf2 and Rrs1 are required for recruiting rpL5, rpL11, and 5S rRNA into preribosomes. In the absence of association of these molecules with pre-rRNPs, processing of 27SB pre-rRNA is blocked. Consequently, the abortive 66S pre-rRNPs are prematurely released from the nucleolus to the nucleoplasm, and cannot be exported to the cytoplasm.

  20. Leaching of Plastic Additives to Marine Organisms

    NARCIS (Netherlands)

    Koelmans, A.A.; Besseling, E.; Foekema, E.M.

    2014-01-01

    It is often assumed that ingestion of microplastics by aquatic species leads to increased exposure to plastic additives. However, experimental data or model based evidence is lacking. Here we assess the potential of leaching of nonylphenol (NP) and bisphenol A (BPA) in the intestinal tracts of Areni

  1. Plastic design of continuous composite slabs

    NARCIS (Netherlands)

    Stark, J.W.B.; Brekelmans, J.W.P.M.

    1996-01-01

    Most current regulations for continuous composite slabs contain rules that limit the application of plastic analysis in the design process. In this paper, results of numerical studies for positive and negative bending and experimental results for negative bending are presented. From these

  2. Leaching of Plastic Additives to Marine Organisms

    NARCIS (Netherlands)

    Koelmans, A.A.; Besseling, E.; Foekema, E.M.

    2014-01-01

    It is often assumed that ingestion of microplastics by aquatic species leads to increased exposure to plastic additives. However, experimental data or model based evidence is lacking. Here we assess the potential of leaching of nonylphenol (NP) and bisphenol A (BPA) in the intestinal tracts of Areni

  3. RP-HPLC法测定奋乃静片的含量%Determination of perphenazine tablets by RP-HPLC

    Institute of Scientific and Technical Information of China (English)

    胡丹; 吕长淮; 吴玮; 尹创

    2012-01-01

    目的 建立RP-HPLC法测定奋乃静片的含量.方法 采用 Agilent C18色谱柱(5 μm,4.6 mm×150 mm),柱温为30℃,以甲醇-磷酸盐缓冲液(取磷酸二氢钾1.36 g,加水溶解并稀释成1 000 ml,加三乙胺4 ml,用磷酸调pH至3.02)(70:30)为流动相,流速为1 ml·min-1,检测波长为256 nm.结果奋乃静在8.048~40.24 mg·L-1的范围内线性关系良好(r=0.999 9,n=5),测得平均回收率为99.6%,RSD=1.09%(n=9).结论 该方法稳定可靠,重现性好,可有效控制奋乃静片的质量.%Objective To develop an HPLC method for the determination of the content of perphenazine tablets. Methods Agilent C18 column( 5μm,4. 6 mm x 150 mm )was used,the column temperature was 30℃,and the mobile phase was methanol-phosphate buffer solution ( 1. 36 g potassium dihydrogen phosphate dissolved and diluted into 1 000 ml by water,added with triethylamine 4 ml,adjusted to pH 3.02 with phosphoric acid ) ( 70:30 ) at the flow rate of 1. 0 ml · Min-1. The UV detection wavelength was 256 nm. Results The linear range was from 8.048 to 40. 24 mg · L-1( r =0. 999 9,n =5 ). The average recovery was 99.6% with RSD of 1.09% ( n = 9 ). Conclusion This method is stable,reliable and reproducible, which can be used for the quality control of perphenazine tablets.

  4. A Calcium-Dependent Plasticity Rule for HCN Channels Maintains Activity Homeostasis and Stable Synaptic Learning

    Science.gov (United States)

    Honnuraiah, Suraj; Narayanan, Rishikesh

    2013-01-01

    for experimentally observed plasticity in HCN channels accompanying synaptic plasticity in hippocampal neurons, and uncover potential links between HCN-channel plasticity and calcium influx, dynamic gain control and stable synaptic learning. PMID:23390543

  5. Global change and the evolution of phenotypic plasticity in plants.

    Science.gov (United States)

    Matesanz, Silvia; Gianoli, Ernesto; Valladares, Fernando

    2010-09-01

    Global change drivers create new environmental scenarios and selective pressures, affecting plant species in various interacting ways. Plants respond with changes in phenology, physiology, and reproduction, with consequences for biotic interactions and community composition. We review information on phenotypic plasticity, a primary means by which plants cope with global change scenarios, recommending promising approaches for investigating the evolution of plasticity and describing constraints to its evolution. We discuss the important but largely ignored role of phenotypic plasticity in range shifts and review the extensive literature on invasive species as models of evolutionary change in novel environments. Plasticity can play a role both in the short-term response of plant populations to global change as well as in their long-term fate through the maintenance of genetic variation. In new environmental conditions, plasticity of certain functional traits may be beneficial (i.e., the plastic response is accompanied by a fitness advantage) and thus selected for. Plasticity can also be relevant in the establishment and persistence of plants in novel environments that are crucial for populations at the colonizing edge in range shifts induced by climate change. Experimental studies show taxonomically widespread plastic responses to global change drivers in many functional traits, though there is a lack of empirical support for many theoretical models on the evolution of phenotypic plasticity. Future studies should assess the adaptive value and evolutionary potential of plasticity under complex, realistic global change scenarios. Promising tools include resurrection protocols and artificial selection experiments. © 2010 New York Academy of Sciences.

  6. Hebbian plasticity requires compensatory processes on multiple timescales

    Science.gov (United States)

    Gerstner, Wulfram

    2017-01-01

    We review a body of theoretical and experimental research on Hebbian and homeostatic plasticity, starting from a puzzling observation: while homeostasis of synapses found in experiments is a slow compensatory process, most mathematical models of synaptic plasticity use rapid compensatory processes (RCPs). Even worse, with the slow homeostatic plasticity reported in experiments, simulations of existing plasticity models cannot maintain network stability unless further control mechanisms are implemented. To solve this paradox, we suggest that in addition to slow forms of homeostatic plasticity there are RCPs which stabilize synaptic plasticity on short timescales. These rapid processes may include heterosynaptic depression triggered by episodes of high postsynaptic firing rate. While slower forms of homeostatic plasticity are not sufficient to stabilize Hebbian plasticity, they are important for fine-tuning neural circuits. Taken together we suggest that learning and memory rely on an intricate interplay of diverse plasticity mechanisms on different timescales which jointly ensure stability and plasticity of neural circuits. This article is part of the themed issue ‘Integrating Hebbian and homeostatic plasticity’. PMID:28093557

  7. Informative document waste plastics

    NARCIS (Netherlands)

    Nagelhout D; Sein AA; Duvoort GL

    1989-01-01

    This "Informative document waste plastics" forms part of a series of "informative documents waste materials". These documents are conducted by RIVM on the indstruction of the Directorate General for the Environment, Waste Materials Directorate, in behalf of the program of

  8. A Plastic Menagerie

    Science.gov (United States)

    Hadley, Mary Jane

    2010-01-01

    Bobble heads had become quite popular, depicting all sorts of sports figures, animals, and even presidents. In this article, the author describes how her fourth graders made bobble head sculptures out of empty plastic drink bottles. (Contains 1 online resource.)

  9. Cortical plasticity and rehabilitation.

    Science.gov (United States)

    Moucha, Raluca; Kilgard, Michael P

    2006-01-01

    The brain is constantly adapting to environmental and endogenous changes (including injury) that occur at every stage of life. The mechanisms that regulate neural plasticity have been refined over millions of years. Motivation and sensory experience directly shape the rewiring that makes learning and neurological recovery possible. Guiding neural reorganization in a manner that facilitates recovery of function is a primary goal of neurological rehabilitation. As the rules that govern neural plasticity become better understood, it will be possible to manipulate the sensory and motor experience of patients to induce specific forms of plasticity. This review summarizes our current knowledge regarding factors that regulate cortical plasticity, illustrates specific forms of reorganization induced by control of each factor, and suggests how to exploit these factors for clinical benefit.

  10. Mechanical plasticity of cells

    Science.gov (United States)

    Bonakdar, Navid; Gerum, Richard; Kuhn, Michael; Spörrer, Marina; Lippert, Anna; Schneider, Werner; Aifantis, Katerina E.; Fabry, Ben

    2016-10-01

    Under mechanical loading, most living cells show a viscoelastic deformation that follows a power law in time. After removal of the mechanical load, the cell shape recovers only incompletely to its original undeformed configuration. Here, we show that incomplete shape recovery is due to an additive plastic deformation that displays the same power-law dynamics as the fully reversible viscoelastic deformation response. Moreover, the plastic deformation is a constant fraction of the total cell deformation and originates from bond ruptures within the cytoskeleton. A simple extension of the prevailing viscoelastic power-law response theory with a plastic element correctly predicts the cell behaviour under cyclic loading. Our findings show that plastic energy dissipation during cell deformation is tightly linked to elastic cytoskeletal stresses, which suggests the existence of an adaptive mechanism that protects the cell against mechanical damage.

  11. Targeting tumour Cell Plasticity

    Institute of Scientific and Technical Information of China (English)

    Elizabeth D. WILLIAMS

    2009-01-01

    @@ Her research is focused on understanding the mechanisms of tumour progression and metastasis, particularly in uro-logical carcinomas (bladder and prostate). Tumour cell plasticity, including epithelial-mesenchymal transition, is a cen-tral theme in Dr Williams' work.

  12. Md1 and Rp105 regulate innate immunity and viral resistance in zebrafish.

    Science.gov (United States)

    Candel, Sergio; Sepulcre, María P; Espín-Palazón, Raquel; Tyrkalska, Sylwia D; de Oliveira, Sofía; Meseguer, José; Mulero, Victoriano

    2015-06-01

    TLR4 was the first TLR family member identified in mammals and is responsible for the activation of the immune response by bacterial LPS. Later, MD1 and RP105 were shown to form complexes that directly interact with the MD2-TLR4 complex, acting as physiological negative regulators of LPS signaling. Despite the general conservation of various TLR families from fish to mammals, several differences can be appreciated, such as the high tolerance of fish to LPS, the absence of the crucial accessory molecules Md2 and Cd14 for Tlr4 signaling in fish, the absence of Tlr4 in some fish species, and the confirmation that LPS does not signal through Tlr4 in zebrafish. The present study has identified the Rp105 and Md1 homologs in zebrafish, confirming (i) Rp105 and Tlr4 evolved from a common ancestor before the divergence between fish and tetrapods and (ii) the presence of Md1 in teleost fish and the lack of Md2, suggesting that the divergence of these accessory molecules occurred in the tetrapod lineage. Biochemical and functional studies indicate that Md1 binds both Rp105 and Tlr4 in zebrafish. Genetic inhibition of zebrafish Md1 and Rp105 reveals that Md1 or Rp105 deficiency impairs the expression of genes encoding pro-inflammatory and antiviral molecules, leading to increased susceptibility to viral infection. These results shed light on the evolutionary history of Md1 and Rp105 and uncover a previously unappreciated function of these molecules in the regulation of innate immunity.

  13. Laser cutting plastic materials

    Energy Technology Data Exchange (ETDEWEB)

    Van Cleave, R.A.

    1980-08-01

    A 1000-watt CO/sub 2/ laser has been demonstrated as a reliable production machine tool for cutting of plastics, high strength reinforced composites, and other nonmetals. More than 40 different plastics have been laser cut, and the results are tabulated. Applications for laser cutting described include fiberglass-reinforced laminates, Kevlar/epoxy composites, fiberglass-reinforced phenolics, nylon/epoxy laminates, ceramics, and disposable tooling made from acrylic.

  14. Development of plastic surgery

    Directory of Open Access Journals (Sweden)

    Pećanac Marija Đ.

    2015-01-01

    Full Text Available Introduction. Plastic surgery is a medical specialty dealing with corrections of defects, improvements in appearance and restoration of lost function. Ancient Times. The first recorded account of reconstructive plastic surgery was found in ancient Indian Sanskrit texts, which described reconstructive surgeries of the nose and ears. In ancient Greece and Rome, many medicine men performed simple plastic cosmetic surgeries to repair damaged parts of the body caused by war mutilation, punishment or humiliation. In the Middle Ages, the development of all medical braches, including plastic surgery was hindered. New age. The interest in surgical reconstruction of mutilated body parts was renewed in the XVIII century by a great number of enthusiastic and charismatic surgeons, who mastered surgical disciplines and became true artists that created new forms. Modern Era. In the XX century, plastic surgery developed as a modern branch in medicine including many types of reconstructive surgery, hand, head and neck surgery, microsurgery and replantation, treatment of burns and their sequelae, and esthetic surgery. Contemporary and future plastic surgery will continue to evolve and improve with regenerative medicine and tissue engineering resulting in a lot of benefits to be gained by patients in reconstruction after body trauma, oncology amputation, and for congenital disfigurement and dysfunction.

  15. New RP-HPLC Method Development and Validation of Sulfapyridine in Pure and Tablet Dosage Forms

    Directory of Open Access Journals (Sweden)

    B. Tirumaleswara Rao

    2016-02-01

    Full Text Available The objective of this work was to develop a simple, selective, stability indicating RP-HPLC method for the determination of sulfapyridine in pure and in tablet dosage form. The proposed RP-HPLC method was validated in compliance with International Conference on Harmonization guidelines. The mobile phase consists a mixture of Acetonitrile: water: 1.0 % ortho phosphoric acid in the ratio of 70:27:3 v/v/v. Column used ODS, C18 RP- COLUMN (4.6mmx250mm having 5µm particle size. The flow rate was 1.0 mL/min and detection was carried out by UV- visible spectrophotometer and was observed that the maximum absorbance (λmax was obtained at 256nm, retention time 4.40mins. The proposed method has permitted the quantification of sulfapyridine over linearity in the range of 5-30µg/mL and its percentage recovery was found to be 99.99%. The proposed RP-HPLC method of sulfapyridine was also found to be robust and rugged as there was no significant change in the peak area, peak shape and retention time. On the basis of above facts it is concluded that “the developed RP-HPLC method was found to be easily applicable and is expected to be widely used for the routine QC analysis of sulfapyridine in the pharmaceutical industry”.

  16. DNV RP-F116 integrity management of submarine pipeline system

    Energy Technology Data Exchange (ETDEWEB)

    Leinum, B.H.; Etterdal, B. [Det Norske Veritas (DNV), Hoevik (Norway); Augustinovic, Z. [Dong Energy, Fredericia (Denmark); Paula, A. [Det Norske Veritas (DNV), Rio de Janeiro, RJ (Brazil)

    2009-12-19

    The need to keep pipelines operating safely and efficiently is paramount for any operator. Additionally, there is an increasing awareness at both regulatory and public level. Authorities around the world are adopting a more proactive approach as they seek to minimize the risk of human injuries or harm to the environment resulting from pipeline leaks. A joint industry project (JIP) led by DNV Energy is formulating guidelines for how to manage the integrity of submarine pipeline system. The resultant document of recommended practice, DNV RP-F116, will provide the oil and gas industry with a useful tool in an area where no such formal guidance currently exists. This paper gives an overview of the RP and demonstrates the use with a case study for the Siri field. The Siri field is operated by DONG Energy, Denmark and all infield pipelines were subjected to an integrity assessment using the Integrity Management process as outlined in the upcoming DNV RP-116. In parallel with establishing the RP, DNV has further developed the web-based software system, Orbit+, which is aligned with the RP. The software system is implemented and used by Dong Energy. (author)

  17. Insulin Receptor Signaling in POMC, but Not AgRP, Neurons Controls Adipose Tissue Insulin Action.

    Science.gov (United States)

    Shin, Andrew C; Filatova, Nika; Lindtner, Claudia; Chi, Tiffany; Degann, Seta; Oberlin, Douglas; Buettner, Christoph

    2017-06-01

    Insulin is a key regulator of adipose tissue lipolysis, and impaired adipose tissue insulin action results in unrestrained lipolysis and lipotoxicity, which are hallmarks of the metabolic syndrome and diabetes. Insulin regulates adipose tissue metabolism through direct effects on adipocytes and through signaling in the central nervous system by dampening sympathetic outflow to the adipose tissue. Here we examined the role of insulin signaling in agouti-related protein (AgRP) and pro-opiomelanocortin (POMC) neurons in regulating hepatic and adipose tissue insulin action. Mice lacking the insulin receptor in AgRP neurons (AgRP IR KO) exhibited impaired hepatic insulin action because the ability of insulin to suppress hepatic glucose production (hGP) was reduced, but the ability of insulin to suppress lipolysis was unaltered. To the contrary, in POMC IR KO mice, insulin lowered hGP but failed to suppress adipose tissue lipolysis. High-fat diet equally worsened glucose tolerance in AgRP and POMC IR KO mice and their respective controls but increased hepatic triglyceride levels only in POMC IR KO mice, consistent with impaired lipolytic regulation resulting in fatty liver. These data suggest that although insulin signaling in AgRP neurons is important in regulating glucose metabolism, insulin signaling in POMC neurons controls adipose tissue lipolysis and prevents high-fat diet-induced hepatic steatosis. © 2017 by the American Diabetes Association.

  18. Stress Dependence of Transformation Plastic Behavior

    Institute of Scientific and Technical Information of China (English)

    Tatsuo Inoue

    2004-01-01

    Transformation plasticity is known to play an important role in the course of heat treatment processes, and so affect the results of heat treatment simulations, which means that the transformation plasticity coefficient is necessary to be identifies. The authors developed a new method by use of four-point bending system of a beam to identify transformation plasticity coefficient taking advantage of its easiness and high accuracy compared with other conventional methods like tension test, etc., and identified the coefficient for four kinds of steels; plane carbon steel, Cr-steel, Cr-Mo steel and bearing steel. In this paper, further experimental data are presented for the steels if the coefficient Kp during pearlite transformation depend on the applied stress. Obtained results reveals that the stress dependence of Kp is rather trivial except for uncertain tendency detected in plane carbon steel. The relation between the Kp and carbon content included is

  19. The fate of bisphenol A, 4-tert-octylphenol and 4-nonylphenol leached from plastic debris into marine water--experimental studies on biodegradation and sorption on suspended particulate matter and nano-TiO2.

    Science.gov (United States)

    Staniszewska, Marta; Graca, Bożena; Nehring, Iga

    2016-02-01

    Experiments were carried out, the aim of which was to determine the leaching rates for bisphenol A (4,4'-(propane-2,2-diyl)diphenol - BPA), 4-tert-octylphenol (OP), 4-nonylphenol (NP) from polycarbonate and recycled tyre granules into the seawater. Additionally biodegradation, sorption on marine suspended particulate matter and sorption on various types of nano-TiO2 of BPA, OP, NP were studied. Experiments were carried out on plastics at various stages of degradation. The conducted experiment confirmed the flux of BPA, OP and NP from the studied plastics into seawater. The initial photodegradation of the plastic had a significant influence on the amount of the studied components released into water. During the first days of the experiment leaching was weaker from aged materials. After 60 days leaching of BPA and OP was higher for aged plastic compared to unaged. On average, suspension adsorbed OP, BPA and NP from seawater at respective levels of 37%, 75% and 100%. On the other hand, during biodegradation on average 25%, 9% and 2% of OP, BPA and NP respectively are removed from water. Nano-TiO2 of 21 nm pore size diameter adsorbed all the compounds more strongly than nano-TiO2 of 15 nm pores sized coated with Al and stearic acid. The strongest sorption (100%) on different types of nano-TiO2 was that of the most hydrophobic and more linear structured NP with just one phenol group. The weakest sorption was observed in the case of BPA, which is the least hydrophobic, and characterized by higher compared to NP and OP steric hindrance and electrostatic repulsion. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Validation of tsunami inundation model TUNA-RP using OAR-PMEL-135 benchmark problem set

    Science.gov (United States)

    Koh, H. L.; Teh, S. Y.; Tan, W. K.; Kh'ng, X. Y.

    2017-05-01

    A standard set of benchmark problems, known as OAR-PMEL-135, is developed by the US National Tsunami Hazard Mitigation Program for tsunami inundation model validation. Any tsunami inundation model must be tested for its accuracy and capability using this standard set of benchmark problems before it can be gainfully used for inundation simulation. The authors have previously developed an in-house tsunami inundation model known as TUNA-RP. This inundation model solves the two-dimensional nonlinear shallow water equations coupled with a wet-dry moving boundary algorithm. This paper presents the validation of TUNA-RP against the solutions provided in the OAR-PMEL-135 benchmark problem set. This benchmark validation testing shows that TUNA-RP can indeed perform inundation simulation with accuracy consistent with that in the tested benchmark problem set.

  1. AgRP Neural Circuits Mediate Adaptive Behaviors in the Starved State

    Science.gov (United States)

    Padilla, Stephanie L.; Qiu, Jian; Soden, Marta E.; Sanz, Elisenda; Nestor, Casey C; Barker, Forrest D.; Quintana, Albert; Zweifel, Larry S.; Rønnekleiv, Oline K.; Kelly, Martin J.; Palmiter, Richard D.

    2016-01-01

    In the face of starvation animals will engage in high-risk behaviors that would normally be considered maladaptive. Starving rodents for example will forage in areas that are more susceptible to predators and will also modulate aggressive behavior within a territory of limited or depleted nutrients. The neural basis of these adaptive behaviors likely involves circuits that link innate feeding, aggression, and fear. Hypothalamic AgRP neurons are critically important for driving feeding and project axons to brain regions implicated in aggression and fear. Using circuit-mapping techniques, we define a disynaptic network originating from a subset of AgRP neurons that project to the medial nucleus of the amygdala and then to the principle bed nucleus of the stria terminalis, which plays a role in suppressing territorial aggression and reducing contextual fear. We propose that AgRP neurons serve as a master switch capable of coordinating behavioral decisions relative to internal state and environmental cues. PMID:27019015

  2. Accounting for inertia in modal choices: some new evidence using a RP/SP dataset

    DEFF Research Database (Denmark)

    Cherchi, Elisabetta; Manca, Francesco

    2011-01-01

    effect is stable along the SP experiments. Inertia has been studied more extensively with panel datasets, but few investigations have used RP/SP datasets. In this paper we extend previous work in several ways. We test and compare several ways of measuring inertia, including measures that have been...... proposed for both short and long RP panel datasets. We also explore new measures of inertia to test for the effect of “learning” (in the sense of acquiring experience or getting more familiar with) along the SP experiment and we disentangle this effect from the pure inertia effect. A mixed logit model...... is used that allows us to account for both systematic and random taste variations in the inertia effect and for correlations among RP and SP observations. Finally we explore the relation between the utility specification (especially in the SP dataset) and the role of inertia in explaining current choices....

  3. Hypothalamic KLF4 mediates leptin's effects on food intake via AgRP

    Science.gov (United States)

    Imbernon, Monica; Sanchez-Rebordelo, Estrella; Gallego, Rosalia; Gandara, Marina; Lear, Pamela; Lopez, Miguel; Dieguez, Carlos; Nogueiras, Ruben

    2014-01-01

    Krüppel-like factor 4 (KLF4) is a zinc-finger-type transcription factor expressed in a range of tissues that plays multiple functions. We report that hypothalamic KLF4 represents a new transcription factor specifically modulating agouti-related protein (AgRP) expression in vivo. Hypothalamic KLF4 colocalizes with AgRP neurons and is modulated by nutritional status and leptin. Over-expression of KLF4 in the hypothalamic arcuate nucleus (ARC) induces food intake and increases body weight through the specific stimulation of AgRP, as well as blunting leptin sensitivity in lean rats independent of forkhead box protein 01 (FoxO1). Down-regulation of KLF4 in the ARC inhibits fasting-induced food intake in both lean and diet-induced obese (DIO) rats. Silencing KLF4, however, does not, on its own, enhance peripheral leptin sensitivity in DIO rats. PMID:24944903

  4. Hypothalamic KLF4 mediates leptin's effects on food intake via AgRP.

    Science.gov (United States)

    Imbernon, Monica; Sanchez-Rebordelo, Estrella; Gallego, Rosalia; Gandara, Marina; Lear, Pamela; Lopez, Miguel; Dieguez, Carlos; Nogueiras, Ruben

    2014-07-01

    Krüppel-like factor 4 (KLF4) is a zinc-finger-type transcription factor expressed in a range of tissues that plays multiple functions. We report that hypothalamic KLF4 represents a new transcription factor specifically modulating agouti-related protein (AgRP) expression in vivo. Hypothalamic KLF4 colocalizes with AgRP neurons and is modulated by nutritional status and leptin. Over-expression of KLF4 in the hypothalamic arcuate nucleus (ARC) induces food intake and increases body weight through the specific stimulation of AgRP, as well as blunting leptin sensitivity in lean rats independent of forkhead box protein 01 (FoxO1). Down-regulation of KLF4 in the ARC inhibits fasting-induced food intake in both lean and diet-induced obese (DIO) rats. Silencing KLF4, however, does not, on its own, enhance peripheral leptin sensitivity in DIO rats.

  5. Cutting Edge: Regulation of TLR4-driven B cell proliferation by RP105 is not B cell-autonomous

    Science.gov (United States)

    Allen, Jessica L.; Flick, Leah M.; Divanovic, Senad; Jackson, Shaun W.; Bram, Richard; Rawlings, David J.; Finkelman, Fred D.; Karp, Christopher L.

    2012-01-01

    Mechanistic understanding of RP105 has been confounded by the fact that this TLR homolog has appeared to have opposing, cell type-specific effects on TLR4 signaling. While RP105 inhibits TLR4-driven signaling in cell lines and myeloid cells, impaired LPS-driven proliferation by B cells from RP105−/− mice has suggested that RP105 facilitates TLR4 signaling in B cells. We show here that modulation of B cell proliferation by RP105 is not a function of B cell-intrinsic expression of RP105, and identify a mechanistic role for dysregulated BAFF expression in the proliferative abnormalities of B cells from RP105−/− mice: serum BAFF levels are elevated in RP105−/− mice, and partial BAFF neutralization rescues aberrant B cell proliferative responses in such mice. These data indicate that RP105 does not have dichotomous effects on TLR4 signaling, and emphasize the need for caution in interpreting the results of global genetic deletion. PMID:22291190

  6. Cutting edge: regulation of TLR4-driven B cell proliferation by RP105 is not B cell autonomous.

    Science.gov (United States)

    Allen, Jessica L; Flick, Leah M; Divanovic, Senad; Jackson, Shaun W; Bram, Richard; Rawlings, David J; Finkelman, Fred D; Karp, Christopher L

    2012-03-01

    Mechanistic understanding of RP105 has been confounded by the fact that this TLR homolog has appeared to have opposing, cell type-specific effects on TLR4 signaling. Although RP105 inhibits TLR4-driven signaling in cell lines and myeloid cells, impaired LPS-driven proliferation by B cells from RP105(-/-) mice has suggested that RP105 facilitates TLR4 signaling in B cells. In this article, we show that modulation of B cell proliferation by RP105 is not a function of B cell-intrinsic expression of RP105, and identify a mechanistic role for dysregulated BAFF expression in the proliferative abnormalities of B cells from RP105(-/-) mice: serum BAFF levels are elevated in RP105(-/-) mice, and partial BAFF neutralization rescues aberrant B cell proliferative responses in such mice. These data indicate that RP105 does not have dichotomous effects on TLR4 signaling and emphasize the need for caution in interpreting the results of global genetic deletion.

  7. Arcuate hypothalamic AgRP and putative POMC neurons show opposite changes in spiking across multiple timescales

    Science.gov (United States)

    Mandelblat-Cerf, Yael; Ramesh, Rohan N; Burgess, Christian R; Patella, Paola; Yang, Zongfang; Lowell, Bradford B; Andermann, Mark L

    2015-01-01

    Agouti-related-peptide (AgRP) neurons—interoceptive neurons in the arcuate nucleus of the hypothalamus (ARC)—are both necessary and sufficient for driving feeding behavior. To better understand the functional roles of AgRP neurons, we performed optetrode electrophysiological recordings from AgRP neurons in awake, behaving AgRP-IRES-Cre mice. In free-feeding mice, we observed a fivefold increase in AgRP neuron firing with mounting caloric deficit in afternoon vs morning recordings. In food-restricted mice, as food became available, AgRP neuron firing dropped, yet remained elevated as compared to firing in sated mice. The rapid drop in spiking activity of AgRP neurons at meal onset may reflect a termination of the drive to find food, while residual, persistent spiking may reflect a sustained drive to consume food. Moreover, nearby neurons inhibited by AgRP neuron photostimulation, likely including satiety-promoting pro-opiomelanocortin (POMC) neurons, demonstrated opposite changes in spiking. Finally, firing of ARC neurons was also rapidly modulated within seconds of individual licks for liquid food. These findings suggest novel roles for antagonistic AgRP and POMC neurons in the regulation of feeding behaviors across multiple timescales. DOI: http://dx.doi.org/10.7554/eLife.07122.001 PMID:26159614

  8. A novel electrophototrophic bacterium Rhodopseudomonas palustris strain RP2, exhibits hydrocarbonoclastic potential in anaerobic environments

    Directory of Open Access Journals (Sweden)

    Krishnaveni Venkidusamy

    2016-07-01

    Full Text Available An electrophototrophic, hydrocarbonoclastic bacterium Rhodopseudomonas palustris stain RP2 was isolated from the anodic biofilms of hydrocarbon fed microbial electrochemical remediation systems (MERS. Salient properties of the strain RP2 were direct electrode respiration, dissimilatory metal oxide reduction, spore formation, anaerobic nitrate reduction, free living diazotrophy and the ability to degrade n-alkane components of petroleum hydrocarbons in anoxic, photic environments. In acetate fed microbial electrochemical cells, a maximum current density of 305±10 mA/m2 (1000Ω was generated (power density 131.65±10 mW/m2 by strain RP2 with a coulombic efficiency of 46.7 ± 1.3%. Cyclic voltammetry studies showed that anaerobically grown cells of strain RP2 is electrochemically active and likely to transfer electrons extracellularly to solid electron acceptors through membrane bound compounds, however, aerobically grown cells lacked the electrochemical activity. The ability of strain RP2 to produce current (maximum current density 21±3 mA/m2; power density 720±7 µW/m2, 1000Ω using petroleum hydrocarbon (PH as a sole energy source was also examined using an initial concentration of 800 mg l-1 of diesel range hydrocarbons (C9- C36 with a concomitant removal of 47.4 ± 2.7% hydrocarbons in MERS. Here, we also report the first study that shows an initial evidence for the existence of a hydrocarbonoclastic behavior in the strain RP2 when grown in different electron accepting and illuminated conditions (anaerobic and MERS degradation. Such observations reveal the importance of photoorganotrophic growth in the utilization of hydrocarbons from contaminated environments. Identification of such novel petrochemical hydrocarbon degrading electricigens, not only expands the knowledge on the range of bacteria known for the hydrocarbon bioremediation but also shows a biotechnological potential that goes well beyond its applications to MERS.

  9. Mass measurement on the rp-process waiting point {sup 72}Kr

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez, D. [Gesellschaft fuer Schwerionenforschung mbH, Darmstadt (Germany); Kolhinen, V.S. [Jyvaeskylae Univ. (Finland); Audi, G. [CSNSM-IN2P3-Centre National de la Recherche Scientifique (CNRS), 91 - Orsay (FR)] [and others

    2004-06-01

    The mass of one of the three major waiting points in the astrophysical rp-process {sup 72}Kr was measured for the first time with the Penning trap mass spectrometer ISOLTRAP. The measurement yielded a relative mass uncertainty of {delta}m/m=1.2 x 10{sup -7} ({delta}m=8 keV). Other Kr isotopes, also needed for astrophysical calculations, were measured with more than one order of magnitude improved accuracy. We use the ISOLTRAP masses of{sup 72-74}Kr to reanalyze the role of the {sup 72}Kr waiting point in the rp-process during X-ray bursts. (orig.)

  10. Weak interaction rates for Kr and Sr waiting-point nuclei under rp-process conditions

    Energy Technology Data Exchange (ETDEWEB)

    Sarriguren, P., E-mail: sarriguren@iem.cfmac.csic.e [Instituto de Estructura de la Materia, CSIC, Serrano 123, E-28006 Madrid (Spain)

    2009-10-12

    Weak interaction rates are studied in neutron deficient Kr and Sr waiting-point isotopes in ranges of densities and temperatures relevant for the rp process. The nuclear structure is described within a microscopic model (deformed QRPA) that reproduces not only the half-lives but also the Gamow-Teller strength distributions recently measured. The various sensitivities of the decay rates to both density and temperature are discussed. Continuum electron capture is shown to contribute significantly to the weak rates at rp-process conditions.

  11. $\\beta$-Decay Half-Life of the $rp$-Process Waiting Point Nuclide $^{84}$Mo

    CERN Document Server

    Stoker, J B; Bazin, D; Becerril, A; Berryman, J S; Crawford, H L; Estrade, A; Guess, C J; Hitt, G W; Lorusso, G; Matos, M; Minamisono, K; Montes, F; Pereira, J; Perdikakis, G; Schatz, H; Smith, K; Zegers, R G T

    2009-01-01

    A half-life of 2.2 $\\pm$ 0.2 s has been deduced for the ground-state $\\beta$ decay of $^{84}$Mo, more than 1$\\sigma$ shorter than the previously adopted value. $^{84}$Mo is an even-even N = Z nucleus lying on the proton dripline, created during explosive hydrogen burning in Type I X-ray bursts in the rapid proton capture ($rp$) process. The effect of the measured half-life on $rp$-process reaction flow is explored. Implications on theoretical treatments of nuclear deformation in $^{84}$Mo are also discussed.

  12. Geneticand Protein Sequence Analysis of rpS29 from Ailuropoda melanoleuca (giant panda)

    Institute of Scientific and Technical Information of China (English)

    Jie Deng; Xiang Ding; Wanru Hou; Jie Zhong; Li Luo; Bo Song; Ting Wang; Yiling Hou

    2012-01-01

      ToexplorethestructuralcharacteristicofribosomalproteinS29(rpS29)geneofAiluropodamelanoleuca (giantpanda),primersweredesignedbasedontheknownnucleotidesequenceofrpS29genestoclonethecDNAand genomicsequencesofthisgenefromgiantpandabyRT-PCRandPCRstrategyrespectively,andthentheclonedcDNA andgenomicsequencesweresequencedandanalyzedpreliminarily.TheresultsindicatedthatthecDNAfragmentofthe rpS29fromthegiantpandais205bpinsizeinlength,containinganopenreadingframe(ORF)of171bp,encoding56 aminoacids.Thelengthofthegenomicsequenceis1598bp,withthreeexonsandtwointrons.Thecodingsequence showsahighdegreeofhomologytothoseof Homosapiens,Bostaurus,Rattusnorvegicusand Musmusculus with 75%,94.74%,89.47%and88.89%respectively,Whileallthehomologiesforaminoacidsequencesarehighupto 100%.PrimarystructureanalysisrevealedthatthemolecularweightoftheputativerpS29proteinis6.68KD,witha theoreticalpIof10.63.Basedontopologyprediction,therearethreedistincttypesoffunctionalsitesintherpS29 proteinofgiantpanda.

  13. RP and RQA Analysis for Floating Potential Fluctuations in a DC Magnetron Sputtering Plasma

    Science.gov (United States)

    Sabavath, Gopikishan; Banerjee, I.; Mahapatra, S. K.

    2016-04-01

    The nonlinear dynamics of a direct current magnetron sputtering plasma is visualized using recurrence plot (RP) technique. RP comprises the recurrence quantification analysis (RQA) which is an efficient method to observe critical regime transitions in dynamics. Further, RQA provides insight information about the system’s behavior. We observed the floating potential fluctuations of the plasma as a function of discharge voltage by using Langmuir probe. The system exhibits quasi-periodic-chaotic-quasi-periodic-chaotic transitions. These transitions are quantified from determinism, Lmax, and entropy of RQA. Statistical investigations like kurtosis and skewness also studied for these transitions which are in well agreement with RQA results.

  14. Mass Measurement on the rp-Process Waiting Point 72Kr

    CERN Document Server

    Rodríguez, D; Audi, G; Äystö, J; Beck, D; Blaum, K; Bollen, G; Herfurth, F; Jokinen, A; Kellerbauer, A G; Kluge, H J; Oinonen, M; Schatz, H; Sauvan, E; Schwarz, S

    2004-01-01

    The mass of one of the three major waiting points in the astrophysical rp-process 72Kr was measured for the first time with the Penning trap mass spectrometer ISOLTRAP. The measurement yielded a relative mass uncertainty of delta m/m = 1.2x10-7 (delta m=8keV). Other Kr isotopes, also needed for astrophysical calculations, were measured with more than one order of magnitude improved accuracy. We use the ISOLTRAP masses of 72-74Kr to reanalyse the role of the 72Kr waiting point in the rp-process during X-ray bursts.

  15. Astrocyte-Synapse Structural Plasticity

    Directory of Open Access Journals (Sweden)

    Yann Bernardinelli

    2014-01-01

    Full Text Available The function and efficacy of synaptic transmission are determined not only by the composition and activity of pre- and postsynaptic components but also by the environment in which a synapse is embedded. Glial cells constitute an important part of this environment and participate in several aspects of synaptic functions. Among the glial cell family, the roles played by astrocytes at the synaptic level are particularly important, ranging from the trophic support to the fine-tuning of transmission. Astrocytic structures are frequently observed in close association with glutamatergic synapses, providing a morphological entity for bidirectional interactions with synapses. Experimental evidence indicates that astrocytes sense neuronal activity by elevating their intracellular calcium in response to neurotransmitters and may communicate with neurons. The precise role of astrocytes in regulating synaptic properties, function, and plasticity remains however a subject of intense debate and many aspects of their interactions with neurons remain to be investigated. A particularly intriguing aspect is their ability to rapidly restructure their processes and modify their coverage of the synaptic elements. The present review summarizes some of these findings with a particular focus on the mechanisms driving this form of structural plasticity and its possible impact on synaptic structure and function.

  16. Elasto-plastic contact between rollers

    Science.gov (United States)

    Chu, Kunliang; Li, Penghui

    1991-12-01

    Knowledge of the three-dimensional contact stress between roller and rolling road for a strain- hardening material in an elasto-plastic state is limited, to say the least. Mathematical analyses of stress for this problem meet with extreme difficulties. Therefore, experimental approaches are desirable. The experimental elasto-plastic stress analysis method proposed by A. R. Hunter is extended in this investigation. The model material is epoxy resin, which exhibits a frozen nonlinear effective stress-strain behavior similar to that of bearing steel when subjected to a thermal cycle whose maximum temperature is significantly less than the critical temperature of the material. This effective stress-strain curve and an effective birefringence- stress curve were obtained by subjecting uniaxial tensile specimens to constant stress and the appropriate thermal cycle. Then the model was subjected to the same thermal cycle and a uniform distributed load that would develop a plastic zone. The stress distributions on the contact surface and the plastic-zone expansion law were obtained from photomechanical analysis of the slices removed from the model. Several important conclusions were summed up that would greatly improve the roller bearing design.

  17. Sustainable harvest: managing plasticity for resilient crops.

    Science.gov (United States)

    Bloomfield, Justin A; Rose, Terry J; King, Graham J

    2014-06-01

    Maintaining crop production to feed a growing world population is a major challenge for this period of rapid global climate change. No consistent conceptual or experimental framework for crop plants integrates information at the levels of genome regulation, metabolism, physiology and response to growing environment. An important role for plasticity in plants is assisting in homeostasis in response to variable environmental conditions. Here, we outline how plant plasticity is facilitated by epigenetic processes that modulate chromatin through dynamic changes in DNA methylation, histone variants, small RNAs and transposable elements. We present examples of plant plasticity in the context of epigenetic regulation of developmental phases and transitions and map these onto the key stages of crop establishment, growth, floral initiation, pollination, seed set and maturation of harvestable product. In particular, we consider how feedback loops of environmental signals and plant nutrition affect plant ontogeny. Recent advances in understanding epigenetic processes enable us to take a fresh look at the crosstalk between regulatory systems that confer plasticity in the context of crop development. We propose that these insights into genotype × environment (G × E) interaction should underpin development of new crop management strategies, both in terms of information-led agronomy and in recognizing the role of epigenetic variation in crop breeding. © 2014 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.

  18. PREPARATION AND PROPERTIES OF WHEAT GLUTEN/RICE PROTEIN COMPOSITES PLASTICIZED WITH GLYCEROL

    Institute of Scientific and Technical Information of China (English)

    Yan-yan Yang; Kai-zhou Zhang; Yi-hu Song; Qiang Zheng

    2011-01-01

    Environment friendly thermosetting composites were prepared by blending wheat gluten (WG) and rice protein (RP) at different weight ratios with glycerol as plasticizer followed by compression molding the mixture at 120C to crosslink the proteins. Reducing agent of sodium bisulfate and sodium sulfite and crosslinking agent formaldehyde were used to adjust the properties of the composites. Morphology, moisture absorption and tensile properties were evaluated. The results showed that formaldehyde could increase tensile strength of the composites without significant influence on Young's modulus and elongation at break. On the other hand, reducing agents could improve tensile strength and extensibility simultaneously, which was much marked at WG/RP ratios from 7/3 to 3/7.

  19. rp Drell-Yan Process in Color Dipole Model

    Institute of Scientific and Technical Information of China (English)

    ZHAO Hong-Ming; DUAN Chun-Gui

    2002-01-01

    We study pion-proton Orp) Drell-Yan (DY) dilepton production in the target rest frame with color dipole model. The prediction for πp DY cross section at the energies of RHIC and LHC is presented, and it can be compared with the data directly, because it does not need K factor. At the same time, the transverse momentum distribution is shown in quantities, which is not available from the standard parton model. The experimental studies of the process could test the color model for DY dilepton production.

  20. Achieving 5- microsec Simultaneity of 36 RP-80 Detonators

    Science.gov (United States)

    2015-05-01

    duplicated in the experimental setup was the type of replaceable firing line upon which the chart is based. The chart refers to RISI twin -lead blasting...Type Diameter (inches) AWG Resistance per 1,000 ft (ohms) RISI “C” coaxial cable 0.059 (center conductor) ~15 3.18 RISI twin lead blasting wire...was a virtual repeat of shot 8 in terms of setup and performance. Fig. 12 Transfer box configuration for shots 8 and 9 20 Shot 16

  1. Experimental model in hamster (Mesocricetus auratus to study heterologous graft of scars and cutaneous diseases in plastic surgery Modelo experimental no hamster (Mesocricetus auratus para estudo de transplantes heterólogos de cicatrizes e doenças cutâneas em cirurgia plástica

    Directory of Open Access Journals (Sweden)

    Bernardo Hochman

    2004-12-01

    Full Text Available Syrian golden hamster (Mesocricetus auratus has in its cheek pouches sub-epithelium an "Immunologically Privileged Site" which allows the integration of homo- and heterologous graft. This paper describes some anatomical and histological characteristics of that site, as well as analyzes aspects related with its immune properties. It also focuses the advantages of this experimental model over other models which are natural or induced carriers of immunodeficiency. Based on both these advantages and literature, this study aims to establish this model, through the performance of heterologous graft, as another option for the investigation of scar disturbances, as keloids and other diseases which may interest Plastic Surgery, as benign cutaneous lesions, and malignant neoplasias such as skin carcinomas and melanomas. The work also addresses perspectives for using this model, which still is a source scarcely known by Brazilian medical class.O hamster sírio dourado (Mesocricetus auratus possui no subepitélio de suas bolsas jugais um "Local de Privilégio Imunológico", permitindo a integração de homo e heteroenxertos. Este artigo descreve as características anatômicas e histológicas desse local, assim como os aspectos relativos as suas propriedades imunológicas. Cita, também, as vantagens desse modelo experimental sobre outros modelos portadores, naturais ou induzidos, de imunodeficiência. Com base nessas vantagens, e também baseado na literatura, tem o intuito de estabelecer esse modelo, mediante a realização de heteroenxertos, como uma outra opção para investigar distúrbios cicatriciais, como o quelóide, e doenças de interesse em Cirurgia Plástica, como lesões cutâneas benignas e neoplasias malignas como carcinomas e melanoma cutâneo. Tece, ainda, considerações sobre perspectivas de aplicações desse modelo, ainda bastante desconhecido entre a classe médica brasileira.

  2. RP-HPLC法定量测定枸橼酸离子含量%RP-HPLC method for quantitative analysis of citration

    Institute of Scientific and Technical Information of China (English)

    王敏力; 杨鹏云; 侯继锋

    2011-01-01

    Objective:To establish the quantitative determination method of sodium citrate by HPLC in citrate and sucrose containing blood products or dry - heat treated intermediate products. Comparison was also carried out between the developed method and ion exchange HPLC method published in ChP 2005. Methods : An HPLC method was developed to specifically determine sodium citrate on reversed - phase chromatography column with UV detection at 210 nm. The separations were performed at 40℃ on a Waters Symmetry sheild RP - C18 column with a mobile phase of phosphoric acid solution as elution. In each experiment 5 mmol · L-1 sodium citrate standard solution was detected with external standard method to mensurate recovery rate. Five kinds of blood products with a total of 20 batches derived from different manufactures were selected for sodium citrate determination. These products only contain sodium citrate but do not contain sucrose which makes it possible to use IEC - HPLC method issued in ChP 2005 and make it easier to do methodology comparison with RP - HPLC method. Samples were divided into two parts after pre - treatment to do comparison in the recovery rate,linear and consistency. Results : The results showed that the retention time of sodium citrate was in about 5 minutes. Sodium citrate standard solution was injected for 5 times to get recovery results which indicate that RSD( n = 5) was 0. 0% ( calculated by retention time) and 0. 1% ( calculated by peak area ) , respectively. The average recovery was over 99. 0% and linear correlation r was over 0. 999. Statistical data showed that the amount of sodium citrate in 20 batches of blood products determined by RP - HPLC method and IEC - HPLC method has no significant difference ( P > 0. 05 ) and the correlation coefficient r was 0. 9994. These results demonstrated that RP - HPLC method and IEC - HPLC method are highly consistent in sodium citrate quantitative determination. Conclusion : The proposed RP - HPLC

  3. How plastic can phenotypic plasticity be? The branching coral Stylophora pistillata as a model system.

    Directory of Open Access Journals (Sweden)

    Lee Shaish

    Full Text Available Phenotypic plasticity enables multicellular organisms to adjust morphologies and various life history traits to variable environmental challenges. Here, we elucidate fixed and plastic architectural rules for colony astogeny in multiple types of colonial ramets, propagated by cutting from genets of the branching coral Stylophora pistillata from Eilat, the Red Sea. We examined 16 morphometric parameters on 136 one-year old S. pistillata colonies (of seven genotypes, originating from small fragments belonging, each, to one of three single-branch types (single tips, start-up, and advanced bifurcating tips or to structural preparative manipulations (representing a single or two growth axes. Experiments were guided by the rationale that in colonial forms, complexity of evolving phenotypic plasticity can be associated with a degree of structural modularity, where shapes are approached by erecting iterative growth patterns at different levels of coral-colony organization. Analyses revealed plastic morphometric characters at branch level, and predetermined morphometric traits at colony level (only single trait exhibited plasticity under extreme manipulation state. Therefore, under the experimental manipulations of this study, phenotypic plasticity in S. pistillata appears to be related to branch level of organization, whereas colony traits are controlled by predetermined genetic architectural rules. Each level of organization undergoes its own mode of astogeny. However, depending on the original ramet structure, the spherical 3-D colonial architecture in this species is orchestrated and assembled by both developmental trajectories at the branch level, and traits at the colony level of organization. In nature, branching colonial forms are often subjected to harsh environmental conditions that cause fragmentation of colony into ramets of different sizes and structures. Developmental traits that are plastic, responding to fragment structure and are not

  4. SABIC Innovative Plastics: Be the World Best Plastic Resin Manufacturer

    Institute of Scientific and Technical Information of China (English)

    Jenny Du

    2007-01-01

    @@ "SABIC Innovative Plastics is a global supplier of plastic resins, manufacturing and compounding polycarbonate, ABS, SAN, ASA, PPE, PC/ABS, PBT and PEI resins, as well as the LNP* line of high performance specialty compounds," said Hiroshi Yoshida, the Global Market Director for Electronics of SABIC Innovative Plastics based in Tokyo at the press conference held by SABIC Innovative Plastics, November 8th 2007, Shanghai.

  5. Preserving in Plastic.

    Science.gov (United States)

    Wahla, James

    1985-01-01

    Outlines steps for casting insects in permanent molds prepared from commercially available liquid plastic. Also describes dry mountings in glass, acrylic, and petri dishes. The rationale for specimen use, hints for producing quality results, purchasing information, and safety precautions are considered. (DH)

  6. Informative document waste plastics

    NARCIS (Netherlands)

    Nagelhout D; Sein AA; Duvoort GL

    1989-01-01

    This "Informative document waste plastics" forms part of a series of "informative documents waste materials". These documents are conducted by RIVM on the indstruction of the Directorate General for the Environment, Waste Materials Directorate, in behalf of the program of acti

  7. Progress in neural plasticity

    Institute of Scientific and Technical Information of China (English)

    POO; Mu-Ming

    2010-01-01

    One of the properties of the nervous system is the use-dependent plasticity of neural circuits.The structure and function of neural circuits are susceptible to changes induced by prior neuronal activity,as reflected by short-and long-term modifications of synaptic efficacy and neuronal excitability.Regarded as the most attractive cellular mechanism underlying higher cognitive functions such as learning and memory,activity-dependent synaptic plasticity has been in the spotlight of modern neuroscience since 1973 when activity-induced long-term potentiation(LTP) of hippocampal synapses was first discovered.Over the last 10 years,Chinese neuroscientists have made notable contributions to the study of the cellular and molecular mechanisms of synaptic plasticity,as well as of the plasticity beyond synapses,including activity-dependent changes in intrinsic neuronal excitability,dendritic integration functions,neuron-glia signaling,and neural network activity.This work highlight some of these significant findings.

  8. New plastic recycling technology

    Science.gov (United States)

    Greater than 60% of the total plastic content of municipal solid waste is comprised of polyolefins (high-density, low-density, and linear polyethylene and polypropylene. Polyethylene (PE) is the largest-volume component but presents a challenge due to the absence of low-energy de...

  9. Persisting Plastic Addiction

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    The policy on curbing plastic shopping bag use implemented three years ago has produced mixed results In a bustling farmers’market tucked in a narrow street in Xisanqi residential community in north Beijing,stalls selling vegetables,fruits and other foods line the sidewalk.

  10. Plastic response and correlations in athermally sheared amorphous solids

    Science.gov (United States)

    Puosi, F.; Rottler, J.; Barrat, J.-L.

    2016-09-01

    The onset of irreversible deformation in low-temperature amorphous solids is due to the accumulation of elementary events, consisting of spatially and temporally localized atomic rearrangements involving only a few tens of atoms. Recently, numerical and experimental work addressed the issue of spatiotemporal correlations between these plastic events. Here, we provide further insight into these correlations by investigating, via molecular dynamics (MD) simulations, the plastic response of a two-dimensional amorphous solid to artificially triggered local shear transformations. We show that while the plastic response is virtually absent in as-quenched configurations, it becomes apparent if a shear strain was previously imposed on the system. Plastic response has a fourfold symmetry, which is characteristic of the shear stress redistribution following the local transformation. At high shear rate we report evidence for a fluctuation-dissipation relation, connecting plastic response and correlation, which seems to break down if lower shear rates are considered.

  11. 充碳塑料管壳式增湿-去湿淡化装置及过程:模拟和实验研究%Modelling and Experimental Investigation of Humidification Dehumidification Desalination Using a Carbon-Filled-Plastic Shell-Tube Column

    Institute of Scientific and Technical Information of China (English)

    成怀刚; 王世昌

    2007-01-01

    The modelling and experimental investigation of a thermally coupled humidification-dehumidification desalination process using a carbon-filled-polypropylene shell-tube column are presented. A heat/mass transfer model is established to study the correlation among productivity, thermal efficiency, physicochemical parameters (gas/liquid phase temperature, heat/mass transfer coefficient, Reynolds number etc.), and operating conditions (the temperature of feed water, the flow rates of external steam, feed water, and carrier air); at the same time, the effects of operating conditions on the productivity and thermal eficiency of the column are investigated both theoretically and experimentally, which indicate that the optimum flow rates of external steam, feed water, and carrier gas are 0.18, 60, and 10kg·h-1, respectively, and the higher the feed water temperature (≤95℃) is, the greater the productivity and the thermal efficiency will be. Furthermore, performance comparison with the previous study shows that the condensate productivity of this carbon-filled-plastic column is not lower than that of the copper column, which demonstrates the practicability and feasibility of applying such a plastic column to the humidification-dehumidification desalination process.

  12. The MiRP2-Kv3.4 potassium channel: muscling in on Alzheimer's disease.

    Science.gov (United States)

    Choi, Eun; Abbott, Geoffrey W

    2007-09-01

    In this issue of Molecular Pharmacology (p. 665), Pannacione et al. provide evidence of a role for the voltage-gated potassium channel alpha subunit Kv3.4 and its ancillary subunit MiRP2 in beta-amyloid (Abeta) peptide-mediated neuronal death. The MiRP2-Kv3.4 channel complex-previously found to be important in skeletal myocyte physiology-is now argued to be a molecular correlate of the transient outward potassium current up-regulated by Abeta peptide, considered a significant step in the etiology of Alzheimer's disease. The authors conclude that MiRP2 and Kv3.4 are up-regulated by Abeta peptide in a nuclear factor kappaB-dependent fashion at the transcriptional level, and the sea anemone toxin BDS-I is shown to protect against Abeta peptide-mediated cell death by specific blockade of Kv3.4-generated current. The findings lend weight to the premise that specific channels, such as MiRP2-Kv3.4, could hold promise as future therapeutic targets in Alzheimer's disease and potentially other neurodegenerative disorders.

  13. Development and Validation of a RP-HPLC Method for the ...

    African Journals Online (AJOL)

    Erah

    Purpose: To develop and validate a sensitive HPLC method for the separation and ... Methods: Reverse phase (RP) chromatographic separation and estimation was ... Instrumentation ... standards (0.1, 0.5, 1.0, 2.5, 5.0, and 10.0 µg ... addition of a small quantity of the mobile ..... analytical procedures: Text and Methodology.

  14. RP-2 Thermal Stability and Heat Transfer Investigation for Hydrocarbon Boost Engines

    Science.gov (United States)

    VanNoord, J. L.; Stiegemeier, B. R.

    2010-01-01

    A series of electrically heated tube tests were performed at the NASA Glenn Research Center s Heated Tube Facility to investigate the use of RP-2 as a fuel for next generation regeneratively cooled hydrocarbon boost engines. The effect that test duration, operating condition and test piece material have on the overall thermal stability and materials compatibility characteristics of RP-2 were evaluated using copper and 304 stainless steel test sections. The copper tests were run at 1000 psia, heat flux up to 6.0 Btu/in.2-sec, and wall temperatures up to 1180 F. Preliminary results, using measured wall temperature as an indirect indicator of the carbon deposition process, show that in copper test pieces above approximately 850 F, RP-2 begins to undergo thermal decomposition resulting in local carbon deposits. Wall temperature traces show significant local temperature increases followed by near instantaneous drops which have been attributed to the carbon deposition/shedding process in previous investigations. Data reduction is currently underway for the stainless steel test sections and carbon deposition measurements will be performed in the future for all test sections used in this investigation. In conjunction with the existing thermal stability database, these findings give insight into the feasibility of cooling a long life, high performance, high-pressure liquid rocket combustor and nozzle with RP-2.

  15. Arcuate AgRP neurons and the regulation of energy balance

    Directory of Open Access Journals (Sweden)

    Céline eCansell

    2012-12-01

    Full Text Available The arcuate nucleus of the hypothalamus contains at least two crucial populations of neurons that continuously monitor signals reflecting energy status and promote the appropriate behavioral and metabolic responses to changes in energy demand. Neurons making pro-opiomelanocortin (POMC decrease food intake and increase energy expenditure through activation of G protein-coupled receptors melanocortin receptors (MCR via the release of a-melanocyte stimulating hormone. A prevailing idea until recently was that the neighboring neurons expressing the orexigenic neuropeptides, agouti-related protein (AgRP and neuropeptide Y (NPY (AgRP neurons increased feeding by opposing the anorexigenic actions of the POMC neurons. AgRP neurons activation but not POMC neurons inhibition was recently demonstrated to be necessary and sufficient to promote feeding. AgRP expressing axons were identified in mesolimbic, midbrain and pontine structure where they regulate feeding but also feeding-independent functions such as reward or peripheral nutrient partitioning. Post-synaptic Gamma aminobutyric acid (GABA, lasting in a timeline similar to neuromodulation, was identified as the core mechanism by which hunger-activated neurons regulate feeding and non-food related processes in a melanocortin independent manner.

  16. Ablation of AgRP neurons impairs adaption to restricted feeding

    Directory of Open Access Journals (Sweden)

    Keith Tan

    2014-10-01

    Full Text Available While the SCN controls the circadian clock, further evidence suggests the existence of a food-entrainable oscillator (FEO that links behavior to changes in food availability such as during restricted feeding (RF. We found that the activity of AgRP/NPY neurons changed rhythmically during RF suggesting that these neurons are a component of the FEO. We next ablated AgRP/NPY neurons in neonates with diphtheria toxin resulting in the loss of ∼50% of AgRP/NPY neurons. Body weight and food intake were unchanged in adult animals after neonatal ablation, as were the responses to leptin treatment, leptin withdrawal, food deprivation and ghrelin treatment. However, ablated animals showed 30% mortality within 4 days of RF. Moreover, the recovery of body weight and food intake in surviving animals lagged behind controls with an absence of food anticipatory activity even after three days. These findings identify AgRP/NPY neurons as a key cellular component of the food-entrained oscillator.

  17. 75 FR 24740 - Recovery Policy RP9523.5, Debris Removal From Waterways

    Science.gov (United States)

    2010-05-05

    ... SECURITY Federal Emergency Management Agency Recovery Policy RP9523.5, Debris Removal From Waterways AGENCY... view a hard copy of the final policy at the Office of Chief Counsel, Federal Emergency Management... of the major disaster or emergency includes debris removal. This policy was developed to provide...

  18. Dependable and Efficient Clinical Molecular Diagnosis of Chinese RP Patient with Targeted Exon Sequencing.

    Science.gov (United States)

    Yang, Liping; Cui, Hui; Yin, Xiaobei; Dou, Hongliang; Zhao, Lin; Chen, Ningning; Zhang, Jinlu; Zhang, Huirong; Li, Genlin; Ma, Zhizhong

    2015-01-01

    Retinitis pigmentosa (RP) is the most common inherited retinal disease. It is a clinically and genetically heterogeneous disorder, which is why it is particularly challenging to diagnose. The aim of this study was to establish a targeted next-generation sequencing (NGS) approach for the comprehensive, rapid, and cost-effective clinical molecular diagnosis of RP. A specific hereditary eye disease enrichment panel (HEDEP) based on exome capture technology was used to collect the protein coding regions of 371 targeted hereditary eye disease genes, followed by high-throughput sequencing on the Illumina HiSeq2000 platform. From a cohort of 34 Chinese RP families, 13 families were successfully diagnosed; thus, the method achieves a diagnostic rate of approximately 40%. Of 16 pathogenic mutations identified, 11 were novel. Our study demonstrates that targeted capture sequencing offers a rapid and effective method for the molecular diagnosis of RP, which helps to provide a more accurate clinical diagnosis and paves the way for genetic counseling, family planning, and future gene-targeted treatment.

  19. RP-HPTLC method for determination of Voriconazole in bulk and in cream formulation

    Directory of Open Access Journals (Sweden)

    Manali W. Jain

    2017-02-01

    Full Text Available Voriconazole is used as an antifungal agent. A new rapid, simple, economical and environmental friendly Reversed -Phase High-Performance Thin-Layer Chromatography (RP-HPTLC has been developed and validated for quantitative determination of voriconazole in bulk and in cream formulation. RP-HPTLC separation was performed on aluminium plates precoated with silica gel 60RP-18F-254S as the stationary phase using Acetonitrile: Water (60:40% v/v as mobile phase. Quantification was achieved by densitometric analysis at 257 nm over the concentration range of 200–1200 ng/band. The method was found to give compact and well resolved band for Voriconazole at Retention factor (Rf 0.48 ± 0.02. The linear regression analysis data for calibration graph showed good linear relationship with r2 = 0.999. The method was validated for precision, recovery, robustness, ruggedness and sensitivity as per International conference on Harmonization (ICH guidelines. The Limit of Detection (LOD and Limit of Quantification (LOQ were found to be 19.99 ng and 60.60 ng, respectively. The proposed developed RP-HPTLC method can be applied for identification and quantitative determination of Voriconazole in bulk and in cream formulation.

  20. Characterization, tissue distribution and regulation of agouti-related protein (AgRP) in a cyprinid fish (Schizothorax prenanti).

    Science.gov (United States)

    Wei, RongBin; Yuan, DengYue; Wang, Tao; Zhou, ChaoWei; Lin, FangJun; Chen, Hu; Wu, HongWei; Yang, ShiYong; Wang, Yan; Liu, Ju; Gao, YunDi; Li, ZhiQiong

    2013-09-15

    Agouti-related protein (AgRP) is an important neuropeptide involved in the regulation of feeding in both mammals and fish. In this study, we have cloned the full-length cDNA sequence for AgRP in a cyprinid fish (Schizothorax prenanti). The AgRP gene, encoding 126-amino acids, was strongly expressed in the brain. The AgRP gene was detected in embryos at developmental stages. Further, its mRNA was detectable in unfertilized eggs. An experiment was conducted to determine the expression profile of AgRP during short-term and long-term fasting of the hypothalamus. The expression level of AgRP in unfed fish was significantly increased at 3 and 4h post-fasting than in fed fish but did not affect AgRP mRNA expression after 14 days fasting. Overall, our results suggest that AgRP is a conserved peptide that might be involved in the regulation of short-term feeding and other physiological function in Schizothorax prenanti. Copyright © 2013 Elsevier B.V. All rights reserved.

  1. 75 FR 55341 - Recovery Policy, RP 9523.6, Mutual Aid Agreements for Public Assistance and Fire Management...

    Science.gov (United States)

    2010-09-10

    ... SECURITY Federal Emergency Management Agency Recovery Policy, RP 9523.6, Mutual Aid Agreements for Public... comments on Recovery Policy, RP 9523.6, Mutual Aid Agreements for Public Assistance and Fire Management Assistance. This is an existing policy that is scheduled for review to ensure that Recovery...

  2. 75 FR 65366 - Recovery Policy RP9524.2, Landslides and Slope Stability Related to Public Facilities

    Science.gov (United States)

    2010-10-22

    ... SECURITY Federal Emergency Management Agency Recovery Policy RP9524.2, Landslides and Slope Stability Related to Public Facilities AGENCY: Federal Emergency Management Agency, DHS. ACTION: Notice of availability. SUMMARY: This document provides notice of the final Recovery Policy RP9524.2, Landslides and...

  3. 75 FR 33821 - Recovery Policy RP9524.10; Direct Disaster-Related Damage to Eligible Facilities

    Science.gov (United States)

    2010-06-15

    ... SECURITY Federal Emergency Management Agency Recovery Policy RP9524.10; Direct Disaster-Related Damage to Eligible Facilities AGENCY: Federal Emergency Management Agency, DHS. ACTION: Notice of availability... Recovery Policy RP9524.10, Direct Disaster-Related Damage to Eligible Facilities. The purpose of this...

  4. A ninth locus (RP18) for autosomal dominant retinitis pigmentosa maps in the pericentromeric region of chromosome 1.

    Science.gov (United States)

    Xu, S Y; Schwartz, M; Rosenberg, T; Gal, A

    1996-08-01

    We studied a large Danish family of seven generations in which autosomal dominant retinitis pigmentosa (adRP), a heterogeneous genetic form of retinal dystrophy, was segregating. After linkage had been excluded to all known adRP loci on chromosomes 3q, 6p, 7p, 7q, 8q, 17p, 17q and 19q, a genome screening was performed. Positive lod scores suggestive of linkage with values ranging between Z = 1.58-5.36 at theta = 0.04-0.20 were obtained for eight loci on proximal 1p and 1q. Close linkage without recombination and a maximum lod score of 7.22 at theta = 0.00 was found between the adRP locus (RP18) in this family and D1S498 which is on 1q very near the centromere. Analysis of multiply informative meioses suggests that in this family D1S534 and D1S305 flank RP18 in interval 1p13-q23. No linkage has been found to loci from this chromosomal region in six other medium sized adRP families in which the disease locus has been excluded from all known chromosomal regions harbouring an adRP gene or locus suggesting that there is (at least) one further adRP locus to be mapped in the future.

  5. Thermal and catalytic pyrolysis of plastic waste

    OpenAIRE

    Débora Almeida; Maria de Fátima Marques

    2016-01-01

    Abstract The amount of plastic waste is growing every year and with that comes an environmental concern regarding this problem. Pyrolysis as a tertiary recycling process is presented as a solution. Pyrolysis can be thermal or catalytical and can be performed under different experimental conditions. These conditions affect the type and amount of product obtained. With the pyrolysis process, products can be obtained with high added value, such as fuel oils and feedstock for new products. Zeolit...

  6. Development and validation of an RP-HPLC method for simultaneous determination of Ramipril and Amlodipine in tablets

    Institute of Scientific and Technical Information of China (English)

    Shi-Ying Dai; Shi-Ting Qiu; Wei Wu; Chun-Mei Fu

    2013-01-01

    An RP-HPLC method for the simultaneous determination of and Amlodipine (AL)Ramipril (RP) in tablets was developed and validated by Chinese Pharmacopoeia 2010. The linearity of the proposed method was investigated in the range of 0.01-0.25 mg/mL (r2 ¼ 0.9998) for RP and 0.014-0.36 mg/mL (r2 ¼ 0.9997) for AL. The limits of detection (LOD) were 0.06μg/mL and 0.02μg/mL for RP and AL, and the limits of quantitation (LOQ) were 0.2μg/mL and 0.07μg/mL, respectively. Some major impurities and degradation products did not disturb the detection of RP and AL and the assay can thus be considered stability-indicating.

  7. Homeostatic role of heterosynaptic plasticity: Models and experiments

    Directory of Open Access Journals (Sweden)

    Marina eChistiakova

    2015-07-01

    Full Text Available Homosynaptic Hebbian-type plasticity provides a cellular mechanism of learning and refinement of connectivity during development in a variety of biological systems. In this review we argue that a complimentary form of plasticity - heterosynaptic plasticity - represents a necessary cellular component for homeostatic regulation of synaptic weights and neuronal activity. The required properties of a homeostatic mechanism which acutely constrains the runaway dynamics imposed by Hebbian associative plasticity have been well-articulated by theoretical and modeling studies. Such mechanism(s should robustly support the stability of operation of neuronal networks and synaptic competition, include changes at non-active synapses, and operate on a similar time scale to Hebbian-type plasticity. The experimentally observed properties of heterosynaptic plasticity have introduced it as a strong candidate to fulfill this homeostatic role. Subsequent modeling studies which incorporate heterosynaptic plasticity into model neurons with Hebbian synapses (utilizing an STDP learning rule have confirmed its ability to robustly provide stability and competition. In contrast, properties of homeostatic synaptic scaling, which is triggered by extreme and long lasting (hours and days changes of neuronal activity, do not fit two crucial requirements for a hypothetical homeostatic mechanism needed to provide stability of operation in the face of on-going synaptic changes driven by Hebbian-type learning rules. Both the trigger and the time scale of homeostatic synaptic scaling are fundamentally different from those of the Hebbian-type plasticity. We conclude that heterosynaptic plasticity, which is triggered by the same episodes of strong postsynaptic activity and operates on the same time scale as Hebbian-type associative plasticity, is ideally suited to serve homeostatic role during on-going synaptic plasticity.

  8. Stress-strain response of plastic waste mixed soil.

    Science.gov (United States)

    Babu, G L Sivakumar; Chouksey, Sandeep Kumar

    2011-03-01

    Recycling plastic waste from water bottles has become one of the major challenges worldwide. The present study provides an approach for the use plastic waste as reinforcement material in soil. The experimental results in the form of stress-strain-pore water pressure response are presented. Based on experimental test results, it is observed that the strength of soil is improved and compressibility reduced significantly with addition of a small percentage of plastic waste to the soil. The use of the improvement in strength and compressibility response due to inclusion of plastic waste can be advantageously used in bearing capacity improvement and settlement reduction in the design of shallow foundations. Copyright © 2010 Elsevier Ltd. All rights reserved.

  9. A QSPR for the plasticization efficiency of polyvinylchloride plasticizers.

    Science.gov (United States)

    Chandola, Mridula; Marathe, Sujata

    2008-01-01

    A simple quantitative structure property relationship (QSPR) for correlating the plasticization efficiency of 25 polyvinylchloride (PVC) plasticizers was obtained using molecular modeling. The plasticizers studied were-aromatic esters (phthalate, terephthalate, benzoate, trimellitate), aliphatic esters (adipate, sebacate, azelate), citrates and a phosphate. The low temperature flex point, Tf, of plasticized polyvinylchloride resins was considered as an indicator of plasticization efficiency. Initially, we attempted to predict plasticization efficiency of PVC plasticizers from physical and structural descriptors derived from the plasticizer molecule alone. However, the correlation of these descriptors with Tf was not very good with R=0.78 and r2=0.613. This implied that the selected descriptors were unable to predict all the interactions between PVC and plasticizer. Hence, to account for these interactions, a model containing two polyvinylchloride (PVC) chain segments along with a plasticizer molecule in a simulation box was constructed, using molecular mechanics. A good QSPR equation correlating physical and structural descriptors derived from the model to Tf of the plasticized resins was obtained with R=0.954 and r2=0.909.

  10. Unusual predator-prey dynamics under reciprocal phenotypic plasticity.

    Science.gov (United States)

    Mougi, Akihiko

    2012-07-21

    Recent theories and experiments have shown that plasticity, such as an inducible defense or an inducible offense in predator-prey interactions, strongly influences the stability of the population dynamics. However, such plastic adaptation has not been expected to cause unusual dynamics such as antiphase cycles, which occur in experimental predator-prey systems with evolutionary adaptation in the defensive trait of prey. Here I show that antiphase cycles and cryptic cycles (a large population fluctuation in one species with almost no change in the population of the other species) can occur in a predator-prey system when both member species can change their phenotypes through adaptive plasticity (inducible defenses and offenses). I consider a familiar type of predator-prey system in which both species can change their morphology or behavior through phenotypic plasticity. The plasticity, that is, the ability to change between distinct phenotypes, is assumed to occur so as to maximize their fitness. I examined how the reciprocal adaptive plasticity influences the population dynamics. The results show that unusual dynamics such as antiphase population cycles and cryptic cycles can occur when both species show inducible plasticity. The unusual dynamics are particularly likely to occur when the carrying capacity of the prey is small (the density dependence of the prey's growth is strong). The unusual predator-prey dynamics may be induced by phenotypic plasticity as long as the phenotypic change occurs to maximize fitness.

  11. Phenotypic Plasticity and Selection: Nonexclusive Mechanisms of Adaptation.

    Science.gov (United States)

    Grenier, S; Barre, P; Litrico, I

    2016-01-01

    Selection and plasticity are two mechanisms that allow the adaptation of a population to a changing environment. Interaction between these nonexclusive mechanisms must be considered if we are to understand population survival. This review discusses the ways in which plasticity and selection can interact, based on a review of the literature on selection and phenotypic plasticity in the evolution of populations. The link between selection and phenotypic plasticity is analysed at the level of the individual. Plasticity can affect an individual's response to selection and so may modify the end result of genetic diversity evolution at population level. Genetic diversity increases the ability of populations or communities to adapt to new environmental conditions. Adaptive plasticity increases individual fitness. However this effect must be viewed from the perspective of the costs of plasticity, although these are not easy to estimate. It is becoming necessary to engage in new experimental research to demonstrate the combined effects of selection and plasticity for adaptation and their consequences on the evolution of genetic diversity.

  12. Innovative Design of Plastic Bottle Recycling Box Based on ARM

    Directory of Open Access Journals (Sweden)

    Yuedong Xiong

    2014-04-01

    Full Text Available Aiming at the problems of on-site plastic bottles recycling and the reuse of waste, the automatic recycling system was developed on the basis of ARM. As the main controller, ARM not only controls the mechanical system of the collector to recover and break plastic bottles, but also communicates with and rewards the user by the automatic reward system through the wireless network. The experimental prototype test results show: post treated fragments of plastic bottles are small, which are convenient to transport and take advantage of; the operation of recovery is easy, and the interface of man-machine interaction is friendly which is easy to expand functions.

  13. Twenty years of Radiology in RP-10 nuclear reactor protection; Veinte anos de proteccion radiologica en el reactor nuclear RP-10

    Energy Technology Data Exchange (ETDEWEB)

    Zapata, Alejandro L.; Ramos, Fernando T.; Arrieta, Rolando W.B.; Vela Mora, Mariano, E-mail: lzapata@ipen.gob.pe, E-mail: framos@ipen.gob.pe, E-mail: rarrieta@ipen.gob.pe, E-mail: mvela@ipen.gob.pe [Instituto Peruano de Energia Nuclear (IPEN), Lima (Peru)

    2013-07-01

    In this report we present the results about radiation controls during 1990 - 2010, carried out in the Nuclear Reactor RP-10 of the Nuclear Center of Huarangal. These controls and radiological evaluation are of much utility for the radio personnel protection of this one and other reactors, since it allows to compares these variables with respect to the time. From the results obtained in monitoring and radiation controls, we conclude that in no case it has been reached the limits allowed by the Peruvian Regulating Authority. (author)

  14. Content Analysis of Resveratrol in Different Parts of Peanut by RP-HPLC%花生不同部位白藜芦醇RP-HPLC含量分析

    Institute of Scientific and Technical Information of China (English)

    薛晓丽; 张红霞

    2012-01-01

    RP-HPLC method is used to determine the content of resveratrol in different parts of peanut.By the methods of ultrasound assisted extraction method and HPLC separation of high purification process to determine the content of resveratrol in the root,stem,leaf,husk and nut of peanut,and the results showed that the recovery was 99.17%,RSD was 1.17%,the regression equation wasY=5.303 141×10^-6X + 0.777 595 1(r2 = 0.999 9),the linearity range was 0.012~0.036mg/m L.The concentration of resveratrol of peanut seedlings in turn were root,stem,leaf,shell,red and nut,in which,the content of resveratrol of root was the highest,and was 0.844g/kg.RP-HPLC method for detection of resveratrol of peanut is really fast-speed and standard,and has good separation results.Peanut vine can be used with high value and be used as new resources in the development of resveratrol.%采用反相高效液相色谱法(RP-HPLC)检测花生不同部位中白藜芦醇的含量。通过超生提取、高效液相检测花生根、茎、叶、果壳、红衣、果仁中白藜芦醇的含量。结果表明:加样回收率为99.17%,RSD为1.17%,回归方程为:Y=5.303 141×10^-6X+0.777 595 1(r2=0.999 9),线性范围0.012~0.036mg/mL。花生植株中白藜芦醇含量依次为根、茎、叶、果壳、红衣、果仁,其中花生根含量最高为0.844 3g/kg。说明:RP-HPLC法检测花生中白藜芦醇方法快速准确,分离效果好。花生植株可利用价值高,可以作为开发白藜芦醇的新资源。

  15. Sustainable reverse logistics for household plastic waste

    OpenAIRE

    Bing, X

    2014-01-01

    Summary of the thesis titled “Sustainable Reverse Logistics for Household Plastic Waste” PhD Candidate: Xiaoyun Bing Recycled plastic can be used in the manufacturing of plastic products to reduce the use of virgin plastics material. The cost of recycled plastics is usually lower than that of virgin plastics. Therefore, it is environmentally and economically beneficial to improve the plastic recycling system to ensure more plastic waste from households is properly collected and pr...

  16. A two-surface plasticity model for stiff clay

    OpenAIRE

    2015-01-01

    This paper presents a constitutive model for describing some important features of the behavior of natural stiff clay evidenced experimentally such as the limited elastic zone, the presence of strain hardening and softening, and the smooth transition from elastic behavior to a plastic one. The model, namely ACC-2, is an adapted Modified Cam Clay model with two yield surfaces: similarly to bounding surface plasticity theory, an additional yield surface?namely Inner yield surface?was adopted to...

  17. Finite element modelling of manufacturing processes for plastic deformation

    Directory of Open Access Journals (Sweden)

    Fernando Mejía Umaña

    2010-04-01

    Full Text Available The object of the Mechanical and Electrical Engineering Departament's computational mechanics of solids section is to offer industry solutions to problems requiring deeper knowledge regarding the mechanincs of solids and how they can be numerically modelled. This article summarises the foundations of plastic deformation, together with the results obtained during the experimental phase and from modelling two applications of plastic deformation processes being studied as part of mechanical engineering students' undergraduate projects.

  18. Multi-scale modeling and experimental study of twin inception and propagation in hexagonal close-packed materials using a crystal plasticity finite element approach; part II: Local behavior

    Science.gov (United States)

    Abdolvand, Hamidreza; Daymond, Mark R.

    2013-03-01

    In-situ tensile tests are performed on Zircaloy-2 samples with various grain sizes to study twin inception and propagation. Orientation maps of some areas at the surface are measured before and after deformation, using the Electron BackScattered Diffraction (EBSD) technique. Strain fields of the same areas are determined using the digital image correlation technique and are compared with results from Crystal Plasticity Finite Element (CPFE) simulations. Different assumptions are made within the CPFE code to simulate twin propagation. It is observed that the predictions of different models does not really change from one model to another when statistical information on the twins is compared, yet local predictions for each grain, i.e. twin direction, twin variant selection, and twin inception site, do change. Also, it is shown that the twin Schmid factor can vary drastically within grains and that for those grains with a low tendency for twinning this variation may make them susceptible to twinning.

  19. Plasticity modeling & computation

    CERN Document Server

    Borja, Ronaldo I

    2013-01-01

    There have been many excellent books written on the subject of plastic deformation in solids, but rarely can one find a textbook on this subject. “Plasticity Modeling & Computation” is a textbook written specifically for students who want to learn the theoretical, mathematical, and computational aspects of inelastic deformation in solids. It adopts a simple narrative style that is not mathematically overbearing, and has been written to emulate a professor giving a lecture on this subject inside a classroom. Each section is written to provide a balance between the relevant equations and the explanations behind them. Where relevant, sections end with one or more exercises designed to reinforce the understanding of the “lecture.” Color figures enhance the presentation and make the book very pleasant to read. For professors planning to use this textbook for their classes, the contents are sufficient for Parts A and B that can be taught in sequence over a period of two semesters or quarters.

  20. The stress statistics of the first pop-in or discrete plastic event in crystal plasticity

    Science.gov (United States)

    Derlet, P. M.; Maaß, R.

    2016-12-01

    The stress at which the first discrete plastic event occurs is investigated using extreme value statistics. It is found that the average of this critical stress is inversely related to the deforming volume, via an exponentially truncated power-law. This is demonstrated for the first pop-in event observed in experimental nano-indentation data as a function of the indenter volume, and for the first discrete plastic event seen in a dislocation dynamics simulation. When the underlying master distribution of critical stresses is assumed to be a power-law, it becomes possible to extract the density of discrete plastic events available to the crystal, and to understand the exponential truncation as a break-down of the asymptotic Weibull limit.

  1. Cellular Plasticity in Prostate Cancer Bone Metastasis

    Directory of Open Access Journals (Sweden)

    Dima Y. Jadaan

    2015-01-01

    Full Text Available Purpose. Experimental data suggest that tumour cells can reversibly transition between epithelial and mesenchymal states (EMT and MET, a phenomenon known as cellular plasticity. The aim of this review was to appraise the clinical evidence for the role of cellular plasticity in prostate cancer (PC bone metastasis. Methods. An electronic search was performed using PubMed for studies that have examined the differential expression of epithelial, mesenchymal, and stem cell markers in human PC bone metastasis tissues. Results. The review included nineteen studies. More than 60% of the studies used ≤20 bone metastasis samples, and there were several sources of heterogeneity between studies. Overall, most stem cell markers analysed, except for CXCR4, were positively expressed in bone metastasis tissues, while the expression of EMT and MET markers was heterogeneous between and within samples. Several EMT and stemness markers that are involved in osteomimicry, such as Notch, Met receptor, and Wnt/β pathway, were highly expressed in bone metastases. Conclusions. Clinical findings support the role of cellular plasticity in PC bone metastasis and suggest that epithelial and mesenchymal states cannot be taken in isolation when targeting PC bone metastasis. The paper also highlights several challenges in the clinical detection of cellular plasticity.

  2. Understanding cancer stem cell heterogeneity and plasticity

    Institute of Scientific and Technical Information of China (English)

    Dean G Tang

    2012-01-01

    Heterogeneity is an omnipresent feature of mammalian cells in vitro and in vivo.It has been recently realized that even mouse and human embryonic stem cells under the best culture conditions are heterogeneous containing pluripotent as well as partially committed cells.Somatic stem cells in adult organs are also heterogeneous,containing many subpopulations of self-renewing cells with distinct regenerative capacity.The differentiated progeny of adult stem cells also retain significant developmental plasticity that can be induced by a wide variety of experimental approaches.Like normal stem cells,recent data suggest that cancer stem cells(CSCs)similarly display significant phenotypic and functional heterogeneity,and that the CSC progeny can manifest diverse plasticity.Here,I discuss CSC heterogeneity and plasticity in the context of tumor development and progression,and by comparing with normal stem cell development.Appreciation of cancer cell plasticity entails a revision to the earlier concept that only the tumorigenic subset in the tumor needs to be targeted.By understanding the interrelationship between CSCs and their differentiated progeny,we can hope to develop better therapeutic regimens that can prevent the emergence of tumor cell variants that are able to found a new tumor and distant metastases.

  3. Low temperature creep plasticity

    Directory of Open Access Journals (Sweden)

    Michael E. Kassner

    2014-07-01

    Full Text Available The creep behavior of crystalline materials at low temperatures (T < 0.3Tm is discussed. In particular, the phenomenological relationships that describe primary creep are reviewed and analyzed. A discussion of the activation energy for creep at T < 0.3Tm is discussed in terms of the context of higher temperature activation energy. The basic mechanism(s of low temperature creep plasticity are discussed, as well.

  4. RP463: a stabilized technetium-99m complex of a hydrazino nicotinamide derivatized chemotactic peptide for infection imaging.

    Science.gov (United States)

    Edwards, D S; Liu, S; Ziegler, M C; Harris, A R; Crocker, A C; Heminway, S J; Barrett, J A; Bridger, G J; Abrams, M J; Higgins, J D

    1999-01-01

    A HYNIC-conjugated chemotactic peptide (fMLFK-HYNIC) was labeled with (99m)Tc using tricine and TPPTS as coligands. The combination of fMLFK-HYNIC, tricine, and TPPTS with (99m)Tc produced a ternary ligand complex [(99m)Tc(fMLFK-HYNIC)(tricine)(TPPTS)] (RP463). RP463 was synthesized either in two steps, in which the binary ligand complex [(99m)Tc(fMLFK-HYNIC)(tricine)(2)] (RP469) was formed first and then reacted with TPPTS, or in one step by direct reduction of [(99m)Tc]pertechnetate with stannous chloride in the presence of fMLFK-HYNIC, tricine, and TPPTS. The radiolabeling yield for RP463 was usually >/=90% using 10 microg of fMLFK-HYNIC and 100 mCi of [(99m)Tc]pertechnetate. Unlike RP469, which decomposed rapidly in the absence of excess tricine coligand, RP463 was stable in solution for at least 6 h. [(99)Tc]RP463 was prepared and characterized by HPLC and electrospray mass spectrometry. In an in vitro assay, [(99)Tc]RP463 showed an IC(50) of 2 nM against binding of [(3)H]fMLF to receptors on PMNs. [(99)Tc]RP463 also induces effectively the superoxide release of polymorphonuclear leukocytes (PMNs) with an EC(50) value of 0.2 +/- 0.2 nM. The localization of RP463 in the infection foci was assessed in a rabbit infection model. RP463 was cleared from the blood faster than RP469 and was excreted mainly through the renal system. As a result of rapid blood clearance and increased uptake, the target-to-background ratios continuously increased from 1.5 +/- 0.2 at 15 min postinjection to 7.5 +/- 0.4 at 4 h postinjection. Visualization of the infected area could be as early as 2 h. A transient decrease in white blood cell count of 35% was observed during the first 30 min after injection of the HPLC-purified RP463 in the infected rabbit. This suggests that future research in this area should focus on developing highly potent antagonists for chemotactic peptide receptor or other receptors on PMNs and monocytes.

  5. New perspectives in plastic biodegradation.

    Science.gov (United States)

    Sivan, Alex

    2011-06-01

    During the past 50 years new plastic materials, in various applications, have gradually replaced the traditional metal, wood, leather materials. Ironically, the most preferred property of plastics--durability--exerts also the major environmental threat. Recycling has practically failed to provide a safe solution for disposal of plastic waste (only 5% out of 1 trillion plastic bags, annually produced in the US alone, are being recycled). Since the most utilized plastic is polyethylene (PE; ca. 140 million tons/year), any reduction in the accumulation of PE waste alone would have a major impact on the overall reduction of the plastic waste in the environment. Since PE is considered to be practically inert, efforts were made to isolate unique microorganisms capable of utilizing synthetic polymers. Recent data showed that biodegradation of plastic waste with selected microbial strains became a viable solution. Copyright © 2011 Elsevier Ltd. All rights reserved.

  6. Microelectronics plastic molded packaging

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, D.R. [Ktech Corp., Albuquerque, NM (United States); Palmer, D.W.; Peterson, D.W. [Sandia National Lab., Albuquerque, NM (United States)] [and others

    1997-02-01

    The use of commercial off-the-shelf (COTS) microelectronics for nuclear weapon applications will soon be reality rather than hearsay. The use of COTS for new technologies for uniquely military applications is being driven by the so-called Perry Initiative that requires the U.S. Department of Defense (DoD) to accept and utilize commercial standards for procurement of military systems. Based on this philosophy, coupled with several practical considerations, new weapons systems as well as future upgrades will contain plastic encapsulated microelectronics. However, a conservative Department of Energy (DOE) approach requires lifetime predictive models. Thus, the focus of the current project is on accelerated testing to advance current aging models as well as on the development of the methodology to be used during WR qualification of plastic encapsulated microelectronics. An additional focal point involves achieving awareness of commercial capabilities, materials, and processes. One of the major outcomes of the project has been the definition of proper techniques for handling and evaluation of modern surface mount parts which might be used in future systems. This program is also raising the familiarity level of plastic within the weapons complex, allowing subsystem design rules accommodating COTS to evolve. A two year program plan is presented along with test results and commercial interactions during this first year.

  7. A comparison of currents carried by HERG, with and without coexpression of MiRP1, and the native rapid delayed rectifier current. Is MiRP1 the missing link?

    Science.gov (United States)

    Weerapura, Manjula; Nattel, Stanley; Chartier, Denis; Caballero, Ricardo; Hébert, Terence E

    2002-04-01

    Although it has been suggested that coexpression of minK related peptide (MiRP1) is required for reconstitution of native rapid delayed-rectifier current (I(Kr)) by human ether-a-go-go related gene (HERG), currents resulting from HERG (I(HERG)) and HERG plus MiRP1 expression have not been directly compared with native I(Kr). We compared the pharmacological and selected biophysical properties of I(HERG) with and without MiRP1 coexpression in Chinese hamster ovary (CHO) cells with those of guinea-pig I(Kr) under comparable conditions. Comparisons were also made with HERG expressed in Xenopus oocytes. MiRP1 coexpression significantly accelerated I(HERG) deactivation at potentials negative to the reversal potential, but did not affect more physiologically relevant deactivation of outward I(HERG), which remained slower than that of I(Kr). MiRP1 shifted I(HERG) activation voltage dependence in the hyperpolarizing direction, whereas I(Kr) activated at voltages more positive than I(HERG). There were major discrepancies between the sensitivity to quinidine, E-4031 and dofetilide of I(HERG) in Xenopus oocytes compared to I(Kr), which were not substantially affected by coexpression with MiRP1. On the other hand, the pharmacological sensitivity of I(HERG) in CHO cells was indistinguishable from that of I(Kr) and was unaffected by MiRP1 coexpression. We conclude that the properties of I(HERG) in CHO cells are similar in many ways to those of native I(Kr) under the same recording conditions, and that the discrepancies that remain are not reduced by coexpression with MiRP1. These results suggest that the physiological role of MiRP1 may not be to act as an essential consituent of the HERG channel complex carrying native I(Kr).

  8. Interfacial interactions between plastic particles in plastics flotation.

    Science.gov (United States)

    Wang, Chong-qing; Wang, Hui; Gu, Guo-hua; Fu, Jian-gang; Lin, Qing-quan; Liu, You-nian

    2015-12-01

    Plastics flotation used for recycling of plastic wastes receives increasing attention for its industrial application. In order to study the mechanism of plastics flotation, the interfacial interactions between plastic particles in flotation system were investigated through calculation of Lifshitz-van der Waals (LW) function, Lewis acid-base (AB) Gibbs function, and the extended Derjaguin-Landau-Verwey-Overbeek potential energy profiles. The results showed that van der Waals force between plastic particles is attraction force in flotation system. The large hydrophobic attraction, caused by the AB Gibbs function, is the dominant interparticle force. Wetting agents present significant effects on the interfacial interactions between plastic particles. It is found that adsorption of wetting agents promotes dispersion of plastic particles and decreases the floatability. Pneumatic flotation may improve the recovery and purity of separated plastics through selective adsorption of wetting agents on plastic surface. The relationships between hydrophobic attraction and surface properties were also examined. It is revealed that there exists a three-order polynomial relationship between the AB Gibbs function and Lewis base component. Our finding provides some insights into mechanism of plastics flotation.

  9. Migration of plasticizers phthalates, bisphenol A and alkylphenols from plastic containers and evaluation of risk.

    Science.gov (United States)

    Guart, A; Bono-Blay, F; Borrell, A; Lacorte, S

    2011-05-01

    This study investigates the potential migration of plasticisers, plastic components and additives from several plastic water bottles. Compounds studied were phthalates (dimethyl phthalate, di-n-butyl phthalate, benzylbutyl phthalate, bis(2-ethylhexyl) phthalate), bis(2-ethylhexyl) adipate, octylphenol, 4-nonylphenol and bisphenol A. Polycarbonate (PC), high-density polyethylene (HDPE), low-density polyethylene (LDPE), polyethylene terephthalate (PET) and polystyrene (PS) plastics used in the water bottling sector were tested using three kinds of total or specific migration tests: (1) standard method UNE-EN ISO 177; (2) ultrasonic forced extraction; and (3) standard method UNE-EN 13130-1. In addition, bottled waters contained in different plastic materials were analysed to determine the potential migration of target compounds in real conditions. In all cases, samples were solid-phase extracted using Oasis HLB 200 mg cartridges and analysed using GC-MS in scan-acquisition mode. Bisphenol A and 4-nonylphenol were detected in incubated samples, indicating that migration from food plastics can occur at the experimental conditions tested. The total daily intake was calculated according to the levels detected in bottled water and the assessment of the consumers' risk was evaluated taking into consideration toxicological and legislative values.

  10. RP-HPLC法测定增液颗粒中哈巴俄苷的含量%Determination of Harpagoside in "Zengye Granule" by RP-HPLC

    Institute of Scientific and Technical Information of China (English)

    王震; 王岳钧; 袁淑斐; 陈吉平

    2007-01-01

    目的 探索增液颗粒中哈巴俄苷含量的测定指标,以期确立增液颗粒的含量测定项.方法 选择高效液相色谱(RP-HPLC)法测定哈巴俄苷含量.色谱柱为Diamonsil ODS-C18(150mm×4.6mm,5 μm),流动相为乙腈-1%冰醋酸溶液(27:73),检测波长278 nm,流速为1.0 ml/min,柱温25℃.结果 哈巴俄苷在3.06~30.6 μg/ml的范围内呈良好的线性关系,回归方程为Y=3 258.35X-3.16(r=0.999 9),平均回收率为99.1%,RSD=0.30%(n=6).结论 以RP-HPLC法测定哈巴俄苷含量简便、准确、重现性好,可作为增液颗粒的质量控制标准.

  11. Third ventricular coinjection of subthreshold doses of NPY and AgRP stimulate food hoarding and intake and neural activation.

    Science.gov (United States)

    Teubner, Brett J W; Keen-Rhinehart, Erin; Bartness, Timothy J

    2012-01-01

    We previously demonstrated that 3rd ventricular (3V) neuropeptide Y (NPY) or agouti-related protein (AgRP) injection potently stimulates food foraging/hoarding/intake in Siberian hamsters. Because NPY and AgRP are highly colocalized in arcuate nucleus neurons in this and other species, we tested whether subthreshold doses of NPY and AgRP coinjected into the 3V stimulates food foraging, hoarding, and intake, and/or neural activation [c-Fos immunoreactivity (c-Fos-ir)] in hamsters housed in a foraging/hoarding apparatus. In the behavioral experiment, each hamster received four 3V treatments by using subthreshold doses of NPY and AgRP for all behaviors: 1) NPY, 2) AgRP, 3) NPY+AgRP, and 4) saline with a 7-day washout period between treatments. Food foraging, intake, and hoarding were measured 1, 2, 4, and 24 h and 2 and 3 days postinjection. Only when NPY and AgRP were coinjected was food intake and hoarding increased. After identical treatment in separate animals, c-Fos-ir was assessed at 90 min and 14 h postinjection, times when food intake (0-1 h) and hoarding (4-24 h) were uniquely stimulated. c-Fos-ir was increased in several hypothalamic nuclei previously shown to be involved in ingestive behaviors and the central nucleus of the amygdala (CeA), but only in NPY+AgRP-treated animals (90 min and 14 h: magno- and parvocellular regions of the hypothalamic paraventricular nucleus and perifornical area; 14 h only: CeA and sub-zona incerta). These results suggest that NPY and AgRP interact to stimulate food hoarding and intake at distinct times, perhaps released as a cocktail naturally with food deprivation to stimulate these behaviors.

  12. Mass measurement on the rp-process waiting point {sup 72}Kr

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez, D.; Beck, D.; Herfurth, F.; Kluge, H.-J. [GSI, Darmstadt (Germany); Kolhinen, V.S.; Aeystoe, J.; Jokinen, A. [University of Jyvaeskylae, Jyvaeskylae (Finland); Audi, G. [CSNSM-IN2P3-CNRS, Orsay-Campus (France); Blaum, K. [GSI, Darmstadt (Germany); University of Mainz, Institute of Physics, Mainz (Germany); Bollen, G.; Schwarz, S. [Michigan State University, NSCL, East Lansing, MI (United States); Kellerbauer, A.; Sauvan, E. [CERN, Physics Department, Geneva (Switzerland); Oinonen, M. [University of Helsinki, Helsinki Institute of Physics, Helsinki (Finland); Schatz, H. [Michigan State University, NSCL, East Lansing, MI (United States); Michigan State University, Joint Institute for Nuclear Astrophysics, East Lansing, MI (United States)

    2005-09-01

    With the aim of improving nucleosynthesis calculations, we performed for the first time, a direct high-precision mass measurement on the waiting point in the astrophysical rp-process {sup 72}Kr. We used the ISOLTRAP Penning trap mass spectrometer located at ISOLDE/CERN. The measurement yielded a relative mass uncertainty of {delta}m/m=1.2 x 10{sup -7}. In addition, the masses of {sup 73}Kr and {sup 74}Kr were measured directly with relative mass uncertainties of 1.0 x 10{sup -7} and 3 x 10{sup -8}, respectively. We analyzed the role of {sup 72}Kr in the rp-process during X-ray bursts using the ISOLTRAP and previous mass values of {sup 72-74}Kr. (orig.)

  13. [RP-HPLC fingerprint evaluating different ginger juice as processing material].

    Science.gov (United States)

    Zhang, Li; Wang, Zhi-Min; Wang, Wei-Hao; Gao, Hui-Min

    2008-05-01

    To establish a method for comparing the differences between fresh and dried ginger juice. The RP-HPLC fingerprint method was performed on an Alltech C18 column (4.6 mm x 250 mm, 5 microm) with mobile phase in gradient elution composed of A-acetonitrie and B-water at a flow rate: 0.8 mL x min(-1). The detecting wavelength was 280 nm, and the column temperature 25 degrees C. There was no significant difference among the same breed ginger juice of different batches. But there was significant difference between crushed ginger juice and the boiled juice. Trytophan, 6-gingerol were common constituents of the three kinds of ginger juice, the fresh ginger and the dry ginger. Besides, 6-shogaol emerged in the boiled juice. The RP-HPLC fingerprints spectrum can be used to distinguish different ginger juices. And the crushed juice of fresh ginger have the same chemical consititents with the fresh ginger.

  14. Analytical Method Development and Validation for Simultaneous Estimation of Clotrimazole and Tinidazole by RP-HPLC

    Directory of Open Access Journals (Sweden)

    Joshi S

    2015-12-01

    Full Text Available An isocratic reverse phase High Performance Liquid Chromatographic (RP-HPLC method was developed and validated for simultaneous determination of Clotrimazole and Tinidazole in combined pharmaceutical dosage form. The successful separation of Clotrimazole and Tinidazole was achieved using Purospher® C18 (250 mm x 4.6 mm i.d., 5 μm column, with mobile phase consisting Phosphate buffer (pH 3.5: Acetonitrile (45:55. The mobile phase flow rate was 1.0 ml/min and the detection wavelength was 240 nm. The developed RP-HPLC method was validated according to ICH guidelines with respect to linearity, accuracy, precision, specificity and robustness and also the LOD and LOQ values were determined.

  15. Use of recycled plastics in wood plastic composites - a review.

    Science.gov (United States)

    Kazemi Najafi, Saeed

    2013-09-01

    The use of recycled and waste thermoplastics has been recently considered for producing wood plastic composites (WPCs). They have great potential for WPCs manufacturing according to results of some limited researches. This paper presents a detailed review about some essential properties of waste and recycled plastics, important for WPCs production, and of research published on the effect of recycled plastics on the physical and mechanical properties of WPCs.

  16. RP-HPLC Determination of 1,3-Dideoxygalactonojirimycin in Bombycis Faeces

    Institute of Scientific and Technical Information of China (English)

    QI Hui; ZHAO Hui; DING Zhen-ying; ZHU Yuan-yuan

    2011-01-01

    Objective To establish a simple and rapid method for the determination of 1,3-dideoxygalactonojirimycin in Bombycis Faeces, a potent glucosidase inihibitor, by HPLC. Methods A RP-HPLC method with fluorescence detection has been developed. Results The HPLC method developed in this research has a good reliability including accuracy and precision. The detection limit was less than 72 ng. Conclusion This method is sufficiently sensitive for determining 1,3-dideoxygalactonojirimycin in Bombycis Faeces and other related products.

  17. Stability-Indicating RP-HPLC Method for Assay of Silver Lactate

    OpenAIRE

    Srinivasan, V.; Sivaramakrishnan, H.; Karthikeyan, B

    2011-01-01

    A simple, economic and time-efficient stability-indicating, reverse-phase high-performance liquid chromatographic (RP-HPLC) method has been developed for analysis of silver lactate in the presence of degradation products generated by decomposition. When silver lactate was subjected to acid hydrolysis, base hydrolysis, oxidative, photolytic, humidity and thermal stress, degradation was observed during base hydrolysis, oxidation, humidity and thermal stress. The drug was found to be stable to o...

  18. New mass data for the rp-process above Z=32

    CERN Document Server

    Herfurth, F; Dworschak, M; Audi, G; Mukherjee, M; Beck, D; Guenaut, C; Rahaman, S; Weber, C; Lunney, D; Blaum, K; Schwarz, S; Yazidjian, C; Kellerbauer, A; Schweikhard, L; Bollen, G; George, S

    2011-01-01

    High-accuracy mass measurements have been performed with the Penning trap mass spectrometer ISOLTRAP at ISOLDE/CERN. The short-lived nuclides $^{70,71,72,73}$Se, $^{72,73,74,75}$Br, and $^{98,99,100,101,103}$Ag have been measured with an average uncertainty of a few keV. The data are important input for nucleosynthesis calculations of the rp-process beyond Z = 32.

  19. RP - HPLC Method for Determination of Piperine from Piper longum Linn. and Piper nigrum Linn

    OpenAIRE

    2005-01-01

    Piper longum Linn. and Piper nigrum Linn. are used as spices and medicines. Quantitative determination of piperine was undertaken to provide an easy and simple analytical method, which can be used as a routine quality control method. RP-HPLC was performed using methanol and water as mobile phase. The detection and quantification was performed at a wavelength of 345 nm. Linearity of detector response for piperine was between the concentrations 0.005% to 0.1%. The correlation coefficient obtai...

  20. DETERMINATION OF PROTEINS FROM BUFFALO MILK USING HIGH PERFORMANCE LIQUID CROMATOGRAPHY RP-HPLC

    OpenAIRE

    AURELIA PECE; COROIAN C.; BIANCA GHIRILĂ; G. MURESAN; VIOARA MIRESAN

    2013-01-01

    In the hereby paper, we have undertaken a study on buffalo milk proteins, employing high performance liquid chromatography (HPLC). This RP-HPLC technique is commonly employed in the separation and assessment of caseins K, and in the fresh, as well as processed milk. These methods are also successfully applied in the authenticity and origin assessment of certain cheese products and the qualitative analysis of milk in bubalines, ovines, caprines and bovines (Ferreira si Cacote, 2003; Veloso si...

  1. Utilization of Electronic Waste Plastic in Concrete

    Directory of Open Access Journals (Sweden)

    Vivek S. Damal

    2015-04-01

    Full Text Available In India, bitumen pavements are commonly used for highways. Due to the increasing traffic intensity, distress such as rutting and cracking of pavements are very common in Indian roads. Under varying seasonal temperature, flexible pavements tend to become soft in summer and brittle in winter. Investigations revealed that properties of concrete can be better than bitumen roads. But now a day‟s concrete roads are used commonly because concrete roads have more life span than the bitumen roads. In large cities now a day‟s concrete roads are used because concrete roads are more durable, strengthen and having more life span than bitumen roads. Waste plastics and E-waste (electronic waste both by domestic and industrial sectors can be used in the production of asphalt mix. Waste plastic, mainly used for packing are made up of polyethylene, polypropylene, polystyrene. Electronic waste, abbreviated as e-waste, consists of discarded old computers, TVs, refrigerators; radios, etc are basically any electrical or electronic appliance that has reached its end of life. An experimental study is made on the utilization of E-waste particles as fine aggregates in concrete with a percentage replacement ranging from 0 % to 21.5% i.e. (7.5%, 15% and 21.5% on the strength criteria of M30 Concrete. Compressive strength Concrete with and without E- waste plastic as aggregates was observed which exhibits a good strength. The feasibility of utilizing E-waste plastic particles as partial replacement of fine aggregate has been presented. In the present study, compressive strength was investigated for Optimum Cement Content and 7.5% E-plastic content in mix yielded stability and very good in compressive strength of 43 grade cement.

  2. Draft EEC method for the determination of the global migration of plastics constituents into fatty-food simulants: Applicability to lacquers, plastics and laminates

    NARCIS (Netherlands)

    Battum, D. van; Rijk, M.A.H.; Verspoor, R.; Rossi, L.

    1982-01-01

    An experimental study was carried out to establish whether the draft EEC method for the determination of the global migration of constituents from plastics packaging materials into fatty food stimulants could be applied to all plastics, including lacquers and laminates. Some difficulties were

  3. Direct liquefaction of plastics and coprocessing of coal with plastics

    Energy Technology Data Exchange (ETDEWEB)

    Huffman, G.P.; Feng, Z.; Mahajan, V. [Univ. of Kentucky, Lexington, KY (United States)

    1995-12-31

    The objectives of this work were to optimize reaction conditions for the direct liquefaction of waste plastics and the coprocessing of coal with waste plastics. In previous work, the direct liquefaction of medium and high density polyethylene (PE), polypropylene (PPE), poly(ethylene terephthalate) (PET), and a mixed plastic waste, and the coliquefaction of these plastics with coals of three different ranks was studied. The results established that a solid acid catalyst (HZSM-5 zeolite) was highly active for the liquefaction of the plastics alone, typically giving oil yields of 80-95% and total conversions of 90-100% at temperatures of 430-450 {degrees}C. In the coliquefaction experiments, 50:50 mixtures of plastic and coal were used with a tetralin solvent (tetralin:solid = 3:2). Using approximately 1% of the HZSM-5 catalyst and a nanoscale iron catalyst, oil yields of 50-70% and total conversion of 80-90% were typical. In the current year, further investigations were conducted of the liquefaction of PE, PPE, and a commingled waste plastic obtained from the American Plastics Council (APC), and the coprocessing of PE, PPE and the APC plastic with Black Thunder subbituminous coal. Several different catalysts were used in these studies.

  4. Plastic Surgery and Suicide: A Clinical Guide for Plastic Surgeons.

    Science.gov (United States)

    Reddy, Vikram; Coffey, M Justin

    2016-08-01

    Several studies have identified an increased risk of suicide among patient populations which a plastic surgeon may have a high risk of encountering: women undergoing breast augmentation, cosmetic surgery patients, and breast cancer patients. No formal guidelines exist to assist a plastic surgeon when faced with such a patient, and not every plastic surgery team has mental health clinicians that are readily accessible for consultation or referral. The goal of this clinical guide is to offer plastic surgeons a set of practical approaches to manage potentially suicidal patients. In addition, the authors review a screening tool, which can assist surgeons when encountering high-risk patients.

  5. RSAC 6.2 with WinRP 2.0 User Manual

    Energy Technology Data Exchange (ETDEWEB)

    Bradley Schrader

    2005-09-01

    The Radiological Safety Analysis Computer Program (RSAC-6.2) calculates the consequences of a release of radionuclides to the atmosphere. Using a personal computer, a user can generate a fission product inventory from either reactor operating history or a nuclear criticality accident. RSAC-6.2 models the effects of high-efficiency particulate air filters or other cleanup systems and calculates decay and ingrowth during transport through processes, facilities, and the environment. Doses are calculated for resuspension, inhalation, immersion, ground surface, and ingestion pathways. WinRP 2.0, a windows based overlay to RSAC-6.2, assists users in creating and running RSAC-6.2 input files. This users manual contains the mathematical models and operating instructions for RSAC-6.2 and WinRP 2.0. Instructions, screens, and examples are provided to guide the user through the functions provided by RSAC-6.2 and WinRP 2.0. These programs are designed for users who are familiar with radiological dose assessment methods.

  6. Shortening of Wallstent RP during carotid artery stenting requires appropriate stent placement.

    Science.gov (United States)

    Aikawa, Hiroshi; Nagata, Shun-ichi; Onizuka, Masanari; Tsutsumi, Masanori; Iko, Minoru; Kodama, Tomonobu; Nii, Kouhei; Matsubara, Shuko; Etou, Hosei; Go, Yoshinori; Kazekawa, Kiyoshi

    2008-06-01

    Changes in the location and length of the Wallstent RP during carotid artery stenting (CAS) were evaluated using intraoperative videos of 28 patients with carotid artery stenosis who underwent CAS with a 10/20 mm Wallstent RP to determine the appropriate stent placement. The stent was deployed after its midpoint was positioned over a virtual center line, the perpendicular line which crossed the most stenotic point of the lesion on the road mapping image. The length of the stenotic lesion, the changes in the locations of the distal and proximal ends of the stent, and the changes in stent length were examined. The distal end of the stent moved a maximum of 6.1 mm toward the proximal side to a point 19.9 mm from the virtual center line. The proximal end moved a maximum of 11.3 mm toward the distal side to a point 14.7 mm from the virtual center line. The stent length ranged from 37.7 to 44.5 mm (mean 41.2 mm). The 10/20 mm Wallstent RP placed by our technique covers the entire lesion with no less than 5.7 mm of margin over the segment distal to the lesion in patients with stenotic segments shorter than 29.4 mm.

  7. LARC(tm) RP46 Polyimide Low Cost High Temperature Technology

    Science.gov (United States)

    Pater, Ruth H.

    2000-01-01

    The LARC(tm) RP46 polyimide was developed in 1991 at NASA Langley Research Center as an ultra-high-performance composite matrix resin for use in aircraft engine components, as well as a more environmentally friendly alternative to commercially available high temperature matrix resins. The LARC(tm) RP46 polyimide is prepared with non-toxic 3,4'-oxyldianiline(ODA). This chemistry has led to several improved performance characteristics over similar high temperature polyimides. These improvements include: (1) 700 F use temperature; (2) Significantly less moisture absorption; (3) Better chemical corrosion resistance; (4) Greater microcracking resistance; (5) Higher structural durability. The 700 F use temperature LARC(tm) RP46 is 150 F higher than that of commonly used PMR-type high temperature resins. In addition, it features significantly less moisture absorption and is therefore less susceptible to moisture induced damage. It also has better corrosion resistance to chemicals, greater microcracking resistance, and higher durability with regard to structural integrity.

  8. Assessment of Lipophilicity Indices Derived from Retention Behavior of Antioxidant Compounds in RP-HPLC

    Directory of Open Access Journals (Sweden)

    Ioana Anamaria Sima

    2017-03-01

    Full Text Available Reverse phase high pressure liquid chromatography was employed in order to evaluate the lipophilicity of antioxidant compounds from different classes, such as phenolic acids, flavanones, flavanols, flavones, anthocyanins, stilbenes, xantonoids, and proanthocyanidins. The retention time of each compound was measured using five different HPLC columns: RP18 (LiChroCART, Purosphere RP-18e, C8 (Zorbax, Eclipse XDBC8, C16-Amide (Discovery RP-Amide C16, CN100 (Saulentechnik, Lichrosphere, and pentafluorophenyl (Phenomenex, Kinetex PFP, and the mobile phase consisted of methanol and water (0.1% formic acid in different proportions. The measurements were conducted at two different column temperatures, room temperature (22 °C and, in order to mimic the environment from the human body, 37 °C. Furthermore, principal component analysis (PCA was used to obtain new lipophilicity indices and holistic lipophilicity charts. Additionally, highly representative depictions of the chromatographic behavior of the investigated compounds and stationary phases at different temperatures were obtained using two new chemometric approaches, namely two-way joining cluster analysis and sum of ranking differences.

  9. Assessment of Lipophilicity Indices Derived from Retention Behavior of Antioxidant Compounds in RP-HPLC.

    Science.gov (United States)

    Sima, Ioana Anamaria; Kot-Wasik, Agata; Wasik, Andrzej; Namieśnik, Jacek; Sârbu, Costel

    2017-03-29

    Reverse phase high pressure liquid chromatography was employed in order to evaluate the lipophilicity of antioxidant compounds from different classes, such as phenolic acids, flavanones, flavanols, flavones, anthocyanins, stilbenes, xantonoids, and proanthocyanidins. The retention time of each compound was measured using five different HPLC columns: RP18 (LiChroCART, Purosphere RP-18e), C8 (Zorbax, Eclipse XDBC8), C16-Amide (Discovery RP-Amide C16), CN100 (Saulentechnik, Lichrosphere), and pentafluorophenyl (Phenomenex, Kinetex PFP), and the mobile phase consisted of methanol and water (0.1% formic acid) in different proportions. The measurements were conducted at two different column temperatures, room temperature (22 °C) and, in order to mimic the environment from the human body, 37 °C. Furthermore, principal component analysis (PCA) was used to obtain new lipophilicity indices and holistic lipophilicity charts. Additionally, highly representative depictions of the chromatographic behavior of the investigated compounds and stationary phases at different temperatures were obtained using two new chemometric approaches, namely two-way joining cluster analysis and sum of ranking differences.

  10. Application of RP-HPLC in Detecting Content of Ferulic Acid in Fuke Qianjin Capsule

    Directory of Open Access Journals (Sweden)

    Ming-zhi WANG

    2015-09-01

    Full Text Available Objective: To establish a method for the determination of ferulic acid content in Fuke Qianjin Capsule. Methods: Reversed phase high performance liquid chromatography (RP-HPLC was applied in this study, with the detection conditions as follows: chromatographic column: Boston green ODS·min-1, detection wavelength: 316 nm, and column temperature: 30℃. C18 (250 mm × 4.6 mm, 5 μm, mobile phase: methanol-0.1% phosphoric acid (25:75, flow velocity: 1.0 mLResults: Ferulic acid, whose sample size was 0.017760-0.10656 μg, was in favorable linear relationship with the integral value of peak area, with correlation coefficient r=0.9998. The average sample-injecting recovery rate and degree of precision (RSD were 97.6% (n=6 and 1.6%, respectively. The results of this study also showed that the specificity of RP-HPLC in this study was excellent; negative samples had no interference on chromatographic peak of target substance (ferulic acid; and RSD of accuracy, repeatability, stability and recovery rate were 1.1%, 1.4%, 1.2% and 1.6%, respectively.Conclusion: RP-HPLC is accurate, rapid, stable and convenient, so it can be used as an optimal method for the detection of ferulic acid content in Fuke Qianjin Capsule.

  11. Modeling plasticity of materials with nanostructure

    Science.gov (United States)

    Kudinova, N. R.

    2017-02-01

    A new approach to modeling of the plasticity of materials with the particle size in the range from 3 to 20 nm (nanostructure) has been proposed. It is based on classical thermodynamic approach employing the surface tension of nanoparticles. Its main advantage is the minimum number of physical parameters in use. In the context of the proposed model, we calculated the dependence of the melting temperature on the nanoparticle size which is consistent with experimental data. The volume density of the surface energy of nanoparticles was also determined. This energy is assumed to be a significant part of the internal energy during deformation Yield point was interpreted as the result of changes of grains surface energy during the deformation. The obtained yield point dependence on the grain size was related to the Hall–Petch law, and this resulted in confirmation of the hypothesis on the crucial role of surface tension forces in the initial stage of plastic deformation of nanomaterials.

  12. Resin injection in clays with high plasticity

    Science.gov (United States)

    Nowamooz, Hossein

    2016-11-01

    Regarding the injection process of polyurethane resins in clays with high plasticity, this paper presents the experimental results of the pressuremeter and cone penetration tests before and after injection. A very important increase in pressure limit or in soil resistance can be observed for all the studied depths close to the injection points. An analytical analysis for cylindrical pore cavity expansion in cohesive frictional soils obeying the Mohr-Coulomb criterion was then used to reproduce the pressuremeter tests before and after injection. The model parameters were calibrated by maintaining constant the elasticity parameters as well as the friction angel before and after injection. A significant increase in cohesion was observed because of soil densification after resin expansion. The estimated undrained cohesions, derived from the parameters of the Mohr-Coulomb criterion, were also compared with the cone penetration tests. Globally, the model predictions show the efficiency of resin injection in clay soils with high plasticity.

  13. Determination of n-octanol/water partition coefficient for DDT-related compounds by RP-HPLC with a novel dual-point retention time correction.

    Science.gov (United States)

    Han, Shu-ying; Qiao, Jun-qin; Zhang, Yun-yang; Yang, Li-li; Lian, Hong-zhen; Ge, Xin; Chen, Hong-yuan

    2011-03-01

    n-Octanol/water partition coefficients (P) for DDTs and dicofol were determined by reversed-phase high performance liquid chromatography (RP-HPLC) on a C(18) column using methanol-water mixture as mobile phase. A dual-point retention time correction (DP-RTC) was proposed to rectify chromatographic retention time (t(R)) shift resulted from stationary phase aging. Based on this correction, the relationship between logP and logk(w), the logarithm of the retention factor extrapolated to pure water, was investigated for a set of 12 benzene homologues and DDT-related compounds with reliable experimental P as model compounds. A linear regression logP=(1.10±0.04) logk(w) - (0.60±0.17) was established with correlation coefficient R(2) of 0.988, cross-validated correlation coefficient R(cv)(2) of 0.983 and standard deviation (SD) of 0.156. This model was further validated using four verification compounds, naphthalene, biphenyl, 2,2-bis(4-chlorophenyl)-1,1-dichloroethane (p,p'-DDD) and 2,2-bis(4-chlorophenyl)-1,1-dichloroethene (p,p'-DDE) with similar structure to DDT. The RP-HPLC-determined P values showed good consistency with shake-flask (SFM) or slow-stirring (SSM) results, especially for highly hydrophobic compounds with logP in the range of 4-7. Then, the P values for five DDT-related compounds, 2-(2-chlorophenyl)-2-(4-chlorophenyl)-1,1,1-trichloroethane (o,p'-DDT), 2-(2-chlorophenyl)-2-(4-chlorophenyl)-1,1-dichloroethane (o,p'-DDD), 2-(2-chlorophenyl)-2-(4-chlorophenyl)-1,1-dichloroethene (o,p'-DDE), and 2,2,2-trichloro-1,1-bis(4-chlorophenyl)ethanol (dicofol) and its main degradation product 4,4'-dichlorobenzophenone (p,p'-DBP) were evaluated by the improved RP-HPLC method for the first time. The excellent precision with SD less than 0.03 proved that the novel DP-RTC protocol can significantly increases the determination accuracy and reliability of P by RP-HPLC.

  14. Tree plastic bark

    OpenAIRE

    Casado Arroyo, Carlos

    2016-01-01

    “Tree plastic bark" consiste en la realización de una intervención artística en un entorno natural concreto, generando de esta manera un Site Specific(1). Como hace alusión Rosalind Krauss en sus reflexiones “La escultura en el campo expandido”(2), comenta que su origen esta claramente ligado con el concepto de monumentalidad. La escultura es un monumento, se crea para conmemorar algún hecho o personaje relevante y está realizada para una ubicación concreta. La investigación parte de la id...

  15. Fabrication of plastic biochips

    Energy Technology Data Exchange (ETDEWEB)

    Saaem, Ishtiaq; Ma, Kuo-Sheng; Alam, S. Munir; Tian Jingdong [Department of Biomedical Engineering and Institute for Genome Sciences and Policy, Duke University, Durham, North Carolina 27708 (United States); Department of Medicine and Human Vaccine Institute, Duke University, Durham, North Carolina 27708 (United States); Department of Biomedical Engineering and Institute for Genome Sciences and Policy, Duke University, Durham, North Carolina 27708 (United States)

    2010-07-15

    A versatile surface functionalization procedure based on rf magnetron sputtering of silica was performed on poly(methylmethacrylate), polycarbonate, polypropylene, and cyclic olefin copolymers (Topas 6015). The hybrid thermoplastic surfaces were characterized by x-ray photoelectron spectrometer analysis and contact angle measurements. The authors then used these hybrid materials to perform a sandwich assay targeting an HIV-1 antibody using fluorescent detection and biotinylated peptides immobilized using the bioaffinity of biotin-neutravidin. They found a limit of detection similar to arrays on glass surfaces and believed that this plastic biochip platform may be used for the development of disposable immunosensing and diagnostic applications.

  16. Endocrine regulation of predator-induced phenotypic plasticity.

    Science.gov (United States)

    Dennis, Stuart R; LeBlanc, Gerald A; Beckerman, Andrew P

    2014-11-01

    Elucidating the developmental and genetic control of phenotypic plasticity remains a central agenda in evolutionary ecology. Here, we investigate the physiological regulation of phenotypic plasticity induced by another organism, specifically predator-induced phenotypic plasticity in the model ecological and evolutionary organism Daphnia pulex. Our research centres on using molecular tools to test among alternative mechanisms of developmental control tied to hormone titres, receptors and their timing in the life cycle. First, we synthesize detail about predator-induced defenses and the physiological regulation of arthropod somatic growth and morphology, leading to a clear prediction that morphological defences are regulated by juvenile hormone and life-history plasticity by ecdysone and juvenile hormone. We then show how a small network of genes can differentiate phenotype expression between the two primary developmental control pathways in arthropods: juvenoid and ecdysteroid hormone signalling. Then, by applying an experimental gradient of predation risk, we show dose-dependent gene expression linking predator-induced plasticity to the juvenoid hormone pathway. Our data support three conclusions: (1) the juvenoid signalling pathway regulates predator-induced phenotypic plasticity; (2) the hormone titre (ligand), rather than receptor, regulates predator-induced developmental plasticity; (3) evolution has favoured the harnessing of a major, highly conserved endocrine pathway in arthropod development to regulate the response to cues about changing environments (risk) from another organism (predator).

  17. Stability indicating RP-HPLC method for simultaneous determination of amlodipine and benazepril hydrochloride from their combination drug product.

    Science.gov (United States)

    Naidu, K Raghu; Kale, Udhav N; Shingare, Murlidhar S

    2005-09-01

    A stability indicating reversed-phase HPLC method has been developed and subsequently validated for simultaneous estimation of amlodipine (AM) present as amlodipine besylate (AB), and benazepril hydrochloride (BH) from their combination product. The proposed RP-HPLC method utilizes a Zorbax SB C18, 5 microm, 250 mm x 4.6 mm i.d. column, mobile phase consisting of phosphate buffer and acetonitrile in the proportion of 65:35 (v/v) with apparent pH adjusted to 7.0, and UV detection at 240 nm using a photodiode array detector. AB, BH, and their combination drug product were exposed to thermal, photolytic, hydrolytic, and oxidative stress conditions, and the stressed samples were analysed by the proposed method. Peak homogeneity data of AM and BH peaks obtained using photodiode array detector, in the stressed sample chromatograms, demonstrated the specificity of the method for their estimation in presence of degradants. The described method was linear over a range of 6-14 microg/ml for AM and 12-28 microg/ml for BH. The mean recoveries were 99.91 and 100.53% for AM and BH, respectively. F-test and t-test at 95% confidence level were used to check the intermediate precision data obtained under different experimental setups; the calculated value was found to be less than critical value.

  18. Plastic food packaging and health

    Directory of Open Access Journals (Sweden)

    Raika Durusoy

    2011-02-01

    Full Text Available Plastics have a wide usage in our daily lives. One of their uses is for food packaging and food containers. The aim of this review is to introduce different types of chemicals that can leach from food packaging plastics into foods and cause human exposure and to mention their effects on health. The types of plastics were reviewed under the 13 headings in Turkish Codex Alimentarius and plastics recycling symbols were provided to enable the recognition of the type of plastic when applicable. Chemicals used during the production and that can cause health risks are investigated under the heading of the relevant type of plastic. The most important chemicals from plastic food packaging that can cause toxicity are styrene, 1,3-butadiene, melamine, formaldehyde, acrylamide, di-2-ethylhexyl phthalate, di-2-ethylhexyl adipate, vinyl chloride and bisphenol A. These chemicals have endocrine disrupting, carcinogenic and/or development disrupting effects. These chemicals may leach into foods depending on the chemical properties of the plastic or food, temperature during packaging, processing and storage, exposure to UV and duration of storage. Contact with fatty/oily or acidic foods, heating of the food inside the container, or drinking hot drinks from plastic cups, use of old and scratched plastics and some detergents increase the risk of leaching. The use of plastic containers and packaging for food and beveradges should be avoided whenever possible and when necessary, less harmful types of plastic should be preferred. [TAF Prev Med Bull 2011; 10(1.000: 87-96

  19. The commercialization of plastic surgery.

    Science.gov (United States)

    Swanson, Eric

    2013-09-01

    The last decade has brought a major challenge to the traditional practice of plastic surgery from corporations that treat plastic surgery as a commercial product and market directly to the public. This corporate medicine model may include promotion of a trademarked procedure or device, national advertising that promises stunning results, sales consultants, and claims of innovation, superiority, and improved safety. This article explores the ethics of this business practice and whether corporate medicine is a desirable model for patients and plastic surgeons.

  20. Plastics recycling: challenges and opportunities

    National Research Council Canada - National Science Library

    Jefferson Hopewell; Robert Dvorak; Edward Kosior

    2009-01-01

    .... Advances in technologies and systems for the collection, sorting and reprocessing of recyclable plastics are creating new opportunities for recycling, and with the combined actions of the public...

  1. Americium behaviour in plastic vessels

    Energy Technology Data Exchange (ETDEWEB)

    Legarda, F.; Herranz, M. [Departamento de Ingenieria Nuclear y Mecanica de Fluidos, Escuela Tecnica Superior de Ingenieria de Bilbao, Universidad del Pais Vasco (UPV/EHU), Alameda de Urquijo s/n, 48013 Bilbao (Spain); Idoeta, R., E-mail: raquel.idoeta@ehu.e [Departamento de Ingenieria Nuclear y Mecanica de Fluidos, Escuela Tecnica Superior de Ingenieria de Bilbao, Universidad del Pais Vasco (UPV/EHU), Alameda de Urquijo s/n, 48013 Bilbao (Spain); Abelairas, A. [Departamento de Ingenieria Nuclear y Mecanica de Fluidos, Escuela Tecnica Superior de Ingenieria de Bilbao, Universidad del Pais Vasco (UPV/EHU), Alameda de Urquijo s/n, 48013 Bilbao (Spain)

    2010-07-15

    The adsorption of {sup 241}Am dissolved in water in different plastic storage vessels was determined. Three different plastics were investigated with natural and distilled waters and the retention of {sup 241}Am by these plastics was studied. The same was done by varying vessel agitation time, vessel agitation speed, surface/volume ratio of water in the vessels and water pH. Adsorptions were measured to be between 0% and 70%. The adsorption of {sup 241}Am is minimized with no water agitation, with PET or PVC plastics, and by water acidification.

  2. Experience in initial training required for the recognition of the qualified RP expert in Spain; Experiencia en la formacion requerida para el reconocimiento del experto cualificado en Espana

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez Suarez, M.; Marco Arboli, M.; Menarguez, J.

    2003-07-01

    An important point of the actions inside the European framework to achieve the harmonisation of the training programmes and recognition was included in the European directive 96/29/Euratom which includes definition and specific tasks of the European Qualified Expert on Radiation Protection (RP). Basic syllabus for training of those experts was developed in the communication 98/C 133/03 concerning BSS applications. Although, in the Spanish education system, the training and recognition requirements of the high level qualified experts on RP was defined since 1977, until 2001, the figure of the Technical Qualified Expert on RP does not appear in the legal framework. In December 2002, a new regulation of the Spanish Regulatory Body, CSN, about qualifications to obtain the recognition of RP Expert in Spain (both high qualified and technical RP experts) was published. Concerning the qualified expert on RP, (RP Officer), responsible of the RP Service, which takes charge of the effective protection and advise radioactive and nuclear facilities in Rp aspects,has to be authorised by the regulatory body. to obtain the RP officer diploma, conceded by the CSN, an initial training of 300 hours and a three-year minimum experience are required (for X-ray installation a 6-month experience is enough). The technical qualified expert on RP is the worker who carried out the tasks in the a RP Service under the supervision of the RP officer. A Technician Qualified Expert on RP does not need an specific accreditation of the Regulatory Body, but an initial RP training and a three-month minimum experience are required and has hold a certificate by the RP officer. Continuous training is also required and as well has to receive a certificate from the RP officer. Since 1977, The Institute for energy Studies has been implementing specific training courses for those professionals who want to obtain the diploma of RP officer (high degree qualified RP expert), conceded by the CSN. Since then

  3. [Erythropoietin in plastic surgery].

    Science.gov (United States)

    Günter, C I; Rezaeian, F; Harder, Y; Lohmeyer, J A; Egert, S; Bader, A; Schilling, A F; Machens, H-G

    2013-04-01

    EPO is an autologous hormone, which is known to regulate erythropoiesis. For 30 years it has been used for the therapy of diverse forms of anaemia, such as renal anaemia, tumour-related anaemias, etc. Meanwhile, a multitude of scientific publications were able to demonstrate its pro-regenerative effects after trauma. These include short-term effects such as the inhibition of the "primary injury response" or apoptosis, and mid- and long-term effects for example the stimulation of stem cell recruitment, growth factor production, angiogenesis and re-epithelialisation. Known adverse reactions are increases of thromboembolic events and blood pressure, as well as a higher mortality in patients with tumour anaemias treated with EPO. Scientific investigations of EPO in the field of plastic surgery included: free and local flaps, nerve regeneration, wound healing enhancement after dermal thermal injuries and in chronic wounds.Acute evidence for the clinical use of EPO in the field of plastic surgery is still not satisfactory, due to the insufficient number of Good Clinical Practice (GCP)-conform clinical trials. Thus, the initiation of more scientifically sound trials is indicated.

  4. Optogenetics and synaptic plasticity.

    Science.gov (United States)

    Xie, Yu-feng; Jackson, Michael F; Macdonald, John F

    2013-11-01

    The intricate and complex interaction between different populations of neurons in the brain has imposed limits on our ability to gain detailed understanding of synaptic transmission and its integration when employing classical electrophysiological approaches. Indeed, electrical field stimulation delivered via traditional microelectrodes does not permit the targeted, precise and selective control of neuronal activity amongst a varied population of neurons and their inputs (eg, cholinergic, dopaminergic or glutamatergic neurons). Recently established optogenetic techniques overcome these limitations allowing precise control of the target neuron populations, which is essential for the elucidation of the neural substrates underlying complex animal behaviors. Indeed, by introducing light-activated channels (ie, microbial opsin genes) into specific neuronal populations, optogenetics enables non-invasive optical control of specific neurons with milliseconds precision. These approaches can readily be applied to freely behaving live animals. Recently there is increased interests in utilizing optogenetics tools to understand synaptic plasticity and learning/memory. Here, we summarize recent progress in applying optogenetics in in the study of synaptic plasticity.

  5. Plastic flow of foams and emulsions in a channel

    CERN Document Server

    Dollet, B; Sbragaglia, M

    2014-01-01

    In order to understand the flow profiles of complex fluids, a crucial issue concerns the emergence of spatial correlations among plastic rearrangements exhibiting cooperativity flow behaviour at the macroscopic level. In this paper, the rate of plastic events in a Poiseuille flow is experimentally measured on a confined foam in a Hele-Shaw geometry. The correlation with independently measured velocity profiles is quantified. To go beyond a limitation of the experiments, namely the presence of wall friction which complicates the relation between shear stress and shear rate, we compare the experiments with simulations of emulsion droplets based on the lattice-Boltzmann method, which are performed both with, and without, wall friction. Our results indicate a correlation between the localisation length of the velocity profiles and the localisation length of the number of plastic events. Finally, unprecedented results on the distribution of the orientation of plastic events show that there is a non-trivial correla...

  6. Constitutive modeling and computational implementation for finite strain plasticity

    Science.gov (United States)

    Reed, K. W.; Atluri, S. N.

    1985-01-01

    This paper describes a simple alternate approach to the difficult problem of modeling material behavior. Starting from a general representation for a rate-tpe constitutive equation, it is shown by example how sets of test data may be used to derive restrictions on the scalar functions appearing in the representation. It is not possible to determine these functions from experimental data, but the aforementioned restrictions serve as a guide in their eventual definition. The implications are examined for hypo-elastic, isotropically hardening plastic, and kinematically hardening plastic materials. A simple model for the evolution of the 'back-stress,' in a kinematic-hardening plasticity theory, that is entirely analogous to a hypoelastic stress-strain relation is postulated and examined in detail in modeling finitely plastic tension-torsion test. The implementation of rate-type material models in finite element algorithms is also discussed.

  7. Sequential elution of multiply and singly phosphorylated peptides with polar-copolymerized mixed-mode RP18/SCX material.

    Science.gov (United States)

    Li, Xiuling; Guo, Zhimou; Sheng, Qianying; Xue, Xingya; Liang, Xinmiao

    2012-06-21

    Novel polar-copolymerized mixed-mode RP18/SCX material was developed for feasible phosphopeptide enrichment, in which multiply and singly phosphorylated peptides could be sequentially eluted and separated with high selectivity.

  8. Determination of Nevadensin in Ocimum Basilicum by RP-HPLC%RP-HPLC测定罗勒中石吊兰素的含量

    Institute of Scientific and Technical Information of China (English)

    王绍云; 曹晖; 唐文华; 吴林冬

    2010-01-01

    建立反相-高效液相色谱法(RP-HPLC)测定罗勒(Ocimum basilicum L.)中石吊兰紊的含量.用Microsorb-MV100-5C_(18)(4.6mm×250mm,5μm)色谱柱,甲醇: 1%醋酸=86 : 14(V/V)为流动相,流速为0.5mL/min,检测波长为335nm.石吊兰素浓度在0.27-32.4μg/mL范围内与峰面积线性关系良好(r=0.9999),方法平均回收率大于99%(n=9).方法简单、可靠,可应用于罗勒植物中石吊兰素的含量测定.

  9. Determination of Lipstatin Concentration in Fermentation Broth with Orlistat as Internal Standard by RP-HPLC%RP-HPLC测定利普司他汀的含量

    Institute of Scientific and Technical Information of China (English)

    朱美容; 许勇煌; 王德刚

    2013-01-01

    目的 建立奥利司他中间体利普司他汀发酵效价的RP-HPLC内标检测法.方法 采用ODS色谱柱(4.6 mm×250 mm,3μm),以83%乙腈-水溶液为流动相,以奥利司他为内标物,进样量10 μL,检测波长为195 nm.结果 在0.0~1.0 mg/mL范围内,利普司他汀浓度与峰面积线性关系良好(r =0.999 2).结论 本方法可准确检测发酵液中利普司他汀效价.

  10. RP-HPLC法测定中药白英中大豆苷的含量%RP-HPLCmethod for determination of daidzin in solanum lyratum thunb

    Institute of Scientific and Technical Information of China (English)

    宋敏; 贾玉荣; 佟立今; 孙立新

    2011-01-01

    目的 建立测定白英中大豆苷(Daidzin)含量的RP-HPLC法.方法 色谱柱为Diamonsil-C18柱(250 mm×4.6 mm,5 μm),流动相为乙腈-水-磷酸(16:84:0.1,v/v),检测波长为260 nm,柱温为35 ℃,流速为1.0 mL/min.结果 大豆苷质量浓度在1.0~40.0 μg/mL内线性关系良好(r=0.999 7).大豆苷的平均回收率为100.1%,RSD为1.1%.结论 该方法准确,重复性良好,适用于白英药材的质量控制.%Objective To establish a RP-HPLC method for the determination of daidzin in Solanum lyratum Thunb. Methods A Diamonsil C18 column (250 mm ×4. 6 mm,5 tμm) was used. The mobile phase consisted of acetonitrile-water-phosphoric acid ( 16: 84: 0. 1, v/v). The wavelength was set at 260 nm. Results The linear range of daidzin was 1.0 ~40. 0 μg/mL. The average recovery was 100. 1% ( RSD was 1. 1% ). Conclusion The method is simple, accurate, reproducible, and it could be used for the quality control of Solanum lyratum Thunb.

  11. RP-HPLC法测定药材黑豆中大豆苷的含量%Determination of daidzin in Glycine max (L.) Merr. by RP-HPLC

    Institute of Scientific and Technical Information of China (English)

    陆泉

    2014-01-01

    Objective To establish a RP-HPLC method for the determination of daidzin in Glycine max ( L. ) Merr. Methods A cosmosil C18 column (250 mm×4.6 mm, 5μm) was used. The mobile phase consisted of acetonitrile-0.1 % trifluoroacetic acid ( 12:88, v/v ). The wavelength was set at 254 nm. Results The linear range of daidzin was 1.11~88.8 μg/mL. The average recovery was 99.99%(RSD was 1.45%). Conclusion The method is simple, accurate, reproducible, and it could be used for the quality control of Glycine max (L.) Merr..%目的:建立RP-HPLC法测定黑豆中大豆苷(Daidzin)的含量。方法色谱柱为cosmosil-C18柱(250mm×4.6mm,5μm),流动相为乙腈:0.1%三氟乙酸溶液(12:88,v/v),检测波长为254nm,柱温为25℃,流速为1.0mL/min。结果大豆苷质量浓度在1.11~88.8μg/mL内线性关系良好(R=0.9999)。大豆苷的平均回收率为99.99%,RSD为1.45%。结论该方法准确,重复性良好,适用于黑豆药材的质量控制。

  12. RP-HPLC测定橘红化痰丸中苦杏仁苷的含量%Determination of Amygdalin in Juhong Huatan Wan by RP-HPLC

    Institute of Scientific and Technical Information of China (English)

    蔡桂萍; 司徒伟良; 宋粉云; 钟兆健

    2015-01-01

    Objective To establish a method for determination of amygdalin in Juhong Huatan Wan.MethodsA RP-HPLC method was established. The chromatographic column was Diamonsil C18. The mobile phase was a mixture of methanol-0.1 % phosphoric acid (20:80,v/v). The flow rate was 1.0 mL/min, and the detection wavelength was 210 nm. The column temperature was 30℃. ResultsThe linear range of amygdalin was 5.5-44.0μg/mL (r=0.9991). The average recovery for amygdalin was 100.3 %,withRSD of 0.84 % (n=6).Conclusion This method can be used for quantitative determination of amygdalin in the preparation.%目的建立反相高效液相色谱法(RP-HPLC)测定橘红化痰丸中苦杏仁苷含量的方法。方法色谱柱为Diamonsil C18;流动相为甲醇-0.1%磷酸水溶液(20:80),流速1.0 mL/min;检测波长210 nm;柱温30℃。结果苦杏仁苷在5.5~44.0μg/mL范围内有良好的线性关系(r=0.9991),平均回收率为100.3%,RSD为0.84%(n=6)。结论该法可用于橘红化痰丸中苦杏仁苷的含量测定。

  13. Determination of the content of nicergoline in release tablets by RP-HPLC%RP-HPLC测定尼麦角林缓释片的含量

    Institute of Scientific and Technical Information of China (English)

    邬卫东; 温爱平

    2013-01-01

    Objective:To establish a method for determination of contents in Nicergoline Release Tablets. Methods:An RP-HPLC method was used with Agilent ZORBAX C8 (250mm×4.6mm,5μm) column; the mobile phase consisted of acetonitrile -0.05mol/L phosphate buffer (42∶58) and UV detection at 280 nm. Results:Nicergoline showed good linear relationship in the range of 0.243~0.973μg (γ=1.0000). The average recovery was 99.8%, RSD was 0.64%(n=6). Conclusions:This method is rapid, simple and reproducible, The method can be used for the quality control of nicergoline release tablets.%目的:建立尼麦角林缓释片的含量测定方法。方法:采用RP-HPLC法,以Agilent ZORBAX C8(250mm×4.6mm,5μm)为色谱柱;乙腈-0.05mol/L磷酸盐缓冲液(42∶58)为流动相;检测波长280nm。结果:尼麦角林在0.243~0.973μg范围内,与峰面积呈良好的线性关系(γ=1.0000);平均回收率为99.8%,RSD为0.64%(n=6)。结论:该法快速、简便、重现性好,可用于尼麦角林缓释片的质量控制。

  14. RP{sub P}erformance, a design tool to simulate the thermal performance of high-latitude roof pond buildings (Skytherm North roof ponds); Programa de computo para la simulacion termica de sistemas de techo con estanque para latitudes altas (Skytherm North Roofponds)

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez, A. G.

    2004-07-01

    This article introduces RP{sub P}erformance, a design tool to simulate the thermal performance of high-latitude roof pond buildings (also known as Skytherm North roof ponds). RP{sub P}erformance is an interactive Microsoft Excel spreadsheet that allows users to modify all the parameters that influence the thermal performance of a Skytherm North roof pond building giving as outputs the heating and cooling costs, as well as a series of indoor temperature charts for a roof pond, a highly-insulated reference building, and a conventionally insulated reference building. This article also presents the calibration study of RP{sub P}erformance using experimental results obtained over a nine-month period in an 11.9 m2 test-room located in Muncie, Indiana. (Author)

  15. Suppression of GHS-R in AgRP Neurons Mitigates Diet-Induced Obesity by Activating Thermogenesis.

    Science.gov (United States)

    Wu, Chia-Shan; Bongmba, Odelia Y N; Yue, Jing; Lee, Jong Han; Lin, Ligen; Saito, Kenji; Pradhan, Geetali; Li, De-Pei; Pan, Hui-Lin; Xu, Allison; Guo, Shaodong; Xu, Yong; Sun, Yuxiang

    2017-04-14

    Ghrelin, an orexigenic hormone released primarily from the gut, signals the hypothalamus to stimulate growth hormone release, enhance appetite and promote weight gain. The ghrelin receptor, aka Growth Hormone Secretagogue Receptor (GHS-R), is highly expressed in the brain, with highest expression in Agouti-Related Peptide (AgRP) neurons of the hypothalamus. We recently reported that neuron-specific deletion of GHS-R completely prevents diet-induced obesity (DIO) in mice by activating non-shivering thermogenesis. To further decipher the specific neuronal circuits mediating the metabolic effects of GHS-R, we generated AgRP neuron-specific GHS-R knockout mice (AgRP-Cre;Ghsr(f/f)). Our data showed that GHS-R in AgRP neurons is required for ghrelin's stimulatory effects on growth hormone secretion, acute food intake and adiposity, but not for long-term total food intake. Importantly, deletion of GHS-R in AgRP neurons attenuated diet-induced obesity (DIO) and enhanced cold-resistance in mice fed high fat diet (HFD). The HFD-fed knockout mice showed increased energy expenditure, and exhibited enhanced thermogenic activation in both brown and subcutaneous fat; this implies that GHS-R suppression in AgRP neurons enhances sympathetic outflow. In summary, our results suggest that AgRP neurons are key site for GHS-R mediated thermogenesis, and demonstrate that GHS-R in AgRP neurons plays crucial roles in governing energy utilization and pathogenesis of DIO.

  16. Rapid separation of seed gliadins by reversed-phase ultra performance liquid chromatography (RP-UPLC) and its application in wheat cultivar and germplasm identification.

    Science.gov (United States)

    Han, Caixia; Lu, Xaiobing; Yu, Zitong; Li, Xiaohui; Ma, Wujun; Yan, Yueming

    2015-01-01

    To separate gliadin from wheat flour, a novel and stability-indicating reversed-phase ultra performance liquid chromatography (RP-UPLC) method is established and optimized. A comparative analysis of routine capillary electrophoresis (CE), reversed-phase high-performance liquid chromatography (RP-HPLC), and RP-UPLC was performed and the results showed that the resolution and efficiency of RP-UPLC were significantly higher than those of CE and RP-HPLC. Characteristic RP-UPLC patterns of different bread wheat variety and related species were readily identified. These results demonstrated that our RP-UPLC procedure resulted in significant improvements in sensitivity, speed, and resolution, and thus is highly useful in wheat cultivar and germplasm identification.

  17. Performance and Emission Studies of a SI Engine using Distilled Plastic Pyrolysis Oil-Petrol Blends

    OpenAIRE

    Kumar Kareddula Vijaya; Puli Ravi Kumar; Swarna Kumari A.; Shailesh P.

    2016-01-01

    In the present work, an experimental investigation is carried out to evaluate the use of plastic oil derived from waste plastic which used in a Spark Ignition engine. Experiments are conducted, the measured performance and emissions of plastic oil blends at different proportions are compared with the baseline operation of the SI engine running with gasoline fuel. Engine performance and exhaust gas emissions such as carbon monoxide, total unburned hydrocarbons, carbon dioxide and oxides of nit...

  18. Sustainable reverse logistics for household plastic waste

    NARCIS (Netherlands)

    Bing, X.

    2014-01-01

    Summary of the thesis titled “Sustainable Reverse Logistics for Household Plastic Waste” PhD Candidate: Xiaoyun Bing Recycled plastic can be used in the manufacturing of plastic products to reduce the use of virgin plastics material. The cost of recycled plastics is usually lower than th

  19. Sustainable reverse logistics for household plastic waste

    NARCIS (Netherlands)

    Bing, X.

    2014-01-01

    Summary of the thesis titled “Sustainable Reverse Logistics for Household Plastic Waste” PhD Candidate: Xiaoyun Bing Recycled plastic can be used in the manufacturing of plastic products to reduce the use of virgin plastics material. The cost of recycled plastics is usually lower than

  20. Sustainable reverse logistics for household plastic waste

    NARCIS (Netherlands)

    Bing, X.

    2014-01-01

    Summary of the thesis titled “Sustainable Reverse Logistics for Household Plastic Waste” PhD Candidate: Xiaoyun Bing Recycled plastic can be used in the manufacturing of plastic products to reduce the use of virgin plastics material. The cost of recycled plastics is usually lower than th

  1. Plastics recycling: challenges and opportunities.

    Science.gov (United States)

    Hopewell, Jefferson; Dvorak, Robert; Kosior, Edward

    2009-07-27

    Plastics are inexpensive, lightweight and durable materials, which can readily be moulded into a variety of products that find use in a wide range of applications. As a consequence, the production of plastics has increased markedly over the last 60 years. However, current levels of their usage and disposal generate several environmental problems. Around 4 per cent of world oil and gas production, a non-renewable resource, is used as feedstock for plastics and a further 3-4% is expended to provide energy for their manufacture. A major portion of plastic produced each year is used to make disposable items of packaging or other short-lived products that are discarded within a year of manufacture. These two observations alone indicate that our current use of plastics is not sustainable. In addition, because of the durability of the polymers involved, substantial quantities of discarded end-of-life plastics are accumulating as debris in landfills and in natural habitats worldwide. Recycling is one of the most important actions currently available to reduce these impacts and represents one of the most dynamic areas in the plastics industry today. Recycling provides opportunities to reduce oil usage, carbon dioxide emissions and the quantities of waste requiring disposal. Here, we briefly set recycling into context against other waste-reduction strategies, namely reduction in material use through downgauging or product reuse, the use of alternative biodegradable materials and energy recovery as fuel. While plastics have been recycled since the 1970s, the quantities that are recycled vary geographically, according to plastic type and application. Recycling of packaging materials has seen rapid expansion over the last decades in a number of countries. Advances in technologies and systems for the collection, sorting and reprocessing of recyclable plastics are creating new opportunities for recycling, and with the combined actions of the public, industry and governments it

  2. Plastics recycling: challenges and opportunities

    Science.gov (United States)

    Hopewell, Jefferson; Dvorak, Robert; Kosior, Edward

    2009-01-01

    Plastics are inexpensive, lightweight and durable materials, which can readily be moulded into a variety of products that find use in a wide range of applications. As a consequence, the production of plastics has increased markedly over the last 60 years. However, current levels of their usage and disposal generate several environmental problems. Around 4 per cent of world oil and gas production, a non-renewable resource, is used as feedstock for plastics and a further 3–4% is expended to provide energy for their manufacture. A major portion of plastic produced each year is used to make disposable items of packaging or other short-lived products that are discarded within a year of manufacture. These two observations alone indicate that our current use of plastics is not sustainable. In addition, because of the durability of the polymers involved, substantial quantities of discarded end-of-life plastics are accumulating as debris in landfills and in natural habitats worldwide. Recycling is one of the most important actions currently available to reduce these impacts and represents one of the most dynamic areas in the plastics industry today. Recycling provides opportunities to reduce oil usage, carbon dioxide emissions and the quantities of waste requiring disposal. Here, we briefly set recycling into context against other waste-reduction strategies, namely reduction in material use through downgauging or product reuse, the use of alternative biodegradable materials and energy recovery as fuel. While plastics have been recycled since the 1970s, the quantities that are recycled vary geographically, according to plastic type and application. Recycling of packaging materials has seen rapid expansion over the last decades in a number of countries. Advances in technologies and systems for the collection, sorting and reprocessing of recyclable plastics are creating new opportunities for recycling, and with the combined actions of the public, industry and governments it

  3. Influence of the Repetitive Corrugation on the Mechanism Occuring During Plastic Deformation of CuSn6 Alloy

    Directory of Open Access Journals (Sweden)

    Nuckowski P.M.

    2016-09-01

    Full Text Available This paper presents the research results of CuSn6 alloy strip at semi-hard state, plastically deformed in the process of repetitive corrugation. The influence of process parameters on the mechanical properties and structure of examined alloy were investigated. Examination in high-resolution transmission electron microscopy (HRTEM confirmed the impact of the repetitive corrugation to obtain the nano-scale structures. It has been found, that the application of repetitive corrugation increases the tensile strength (Rm, yield strength (Rp0.2 and elastic limit (Rp0,05 of CuSn6 alloy strips. In the present work it has been confirmed that the repetitive corrugation process is a more efficient method for structure and mechanical properties modification of commercial CuSn6 alloy strip (semi-hard as compared with the classic rolling process.

  4. Homeostatic role of heterosynaptic plasticity: models and experiments

    Science.gov (United States)

    Chistiakova, Marina; Bannon, Nicholas M.; Chen, Jen-Yung; Bazhenov, Maxim; Volgushev, Maxim

    2015-01-01

    Homosynaptic Hebbian-type plasticity provides a cellular mechanism of learning and refinement of connectivity during development in a variety of biological systems. In this review we argue that a complimentary form of plasticity—heterosynaptic plasticity—represents a necessary cellular component for homeostatic regulation of synaptic weights and neuronal activity. The required properties of a homeostatic mechanism which acutely constrains the runaway dynamics imposed by Hebbian associative plasticity have been well-articulated by theoretical and modeling studies. Such mechanism(s) should robustly support the stability of operation of neuronal networks and synaptic competition, include changes at non-active synapses, and operate on a similar time scale to Hebbian-type plasticity. The experimentally observed properties of heterosynaptic plasticity have introduced it as a strong candidate to fulfill this homeostatic role. Subsequent modeling studies which incorporate heterosynaptic plasticity into model neurons with Hebbian synapses (utilizing an STDP learning rule) have confirmed its ability to robustly provide stability and competition. In contrast, properties of homeostatic synaptic scaling, which is triggered by extreme and long lasting (hours and days) changes of neuronal activity, do not fit two crucial requirements for a hypothetical homeostatic mechanism needed to provide stability of operation in the face of on-going synaptic changes driven by Hebbian-type learning rules. Both the trigger and the time scale of homeostatic synaptic scaling are fundamentally different from those of the Hebbian-type plasticity. We conclude that heterosynaptic plasticity, which is triggered by the same episodes of strong postsynaptic activity and operates on the same time scale as Hebbian-type associative plasticity, is ideally suited to serve a homeostatic role during on-going synaptic plasticity. PMID:26217218

  5. Transport and release of chemicals from plastics to the environment and to wildlife

    Science.gov (United States)

    Teuten, Emma L.; Saquing, Jovita M.; Knappe, Detlef R. U.; Barlaz, Morton A.; Jonsson, Susanne; Björn, Annika; Rowland, Steven J.; Thompson, Richard C.; Galloway, Tamara S.; Yamashita, Rei; Ochi, Daisuke; Watanuki, Yutaka; Moore, Charles; Viet, Pham Hung; Tana, Touch Seang; Prudente, Maricar; Boonyatumanond, Ruchaya; Zakaria, Mohamad P.; Akkhavong, Kongsap; Ogata, Yuko; Hirai, Hisashi; Iwasa, Satoru; Mizukawa, Kaoruko; Hagino, Yuki; Imamura, Ayako; Saha, Mahua; Takada, Hideshige

    2009-01-01

    Plastics debris in the marine environment, including resin pellets, fragments and microscopic plastic fragments, contain organic contaminants, including polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons, petroleum hydrocarbons, organochlorine pesticides (2,2′-bis(p-chlorophenyl)-1,1,1-trichloroethane, hexachlorinated hexanes), polybrominated diphenylethers, alkylphenols and bisphenol A, at concentrations from sub ng g–1 to µg g–1. Some of these compounds are added during plastics manufacture, while others adsorb from the surrounding seawater. Concentrations of hydrophobic contaminants adsorbed on plastics showed distinct spatial variations reflecting global pollution patterns. Model calculations and experimental observations consistently show that polyethylene accumulates more organic contaminants than other plastics such as polypropylene and polyvinyl chloride. Both a mathematical model using equilibrium partitioning and experimental data have demonstrated the transfer of contaminants from plastic to organisms. A feeding experiment indicated that PCBs could transfer from contaminated plastics to streaked shearwater chicks. Plasticizers, other plastics additives and constitutional monomers also present potential threats in terrestrial environments because they can leach from waste disposal sites into groundwater and/or surface waters. Leaching and degradation of plasticizers and polymers are complex phenomena dependent on environmental conditions in the landfill and the chemical properties of each additive. Bisphenol A concentrations in leachates from municipal waste disposal sites in tropical Asia ranged from sub µg l–1 to mg l–1 and were correlated with the level of economic development. PMID:19528054

  6. Translational read-through of the RP2 Arg120stop mutation in patient iPSC-derived retinal pigment epithelium cells

    Science.gov (United States)

    Schwarz, Nele; Carr, Amanda-Jayne; Lane, Amelia; Moeller, Fabian; Chen, Li Li; Aguilà, Mònica; Nommiste, Britta; Muthiah, Manickam N.; Kanuga, Naheed; Wolfrum, Uwe; Nagel-Wolfrum, Kerstin; da Cruz, Lyndon; Coffey, Peter J.; Cheetham, Michael E.; Hardcastle, Alison J.

    2015-01-01

    Mutations in the RP2 gene lead to a severe form of X-linked retinitis pigmentosa. RP2 patients frequently present with nonsense mutations and no treatments are currently available to restore RP2 function. In this study, we reprogrammed fibroblasts from an RP2 patient carrying the nonsense mutation c.519C>T (p.R120X) into induced pluripotent stem cells (iPSC), and differentiated these cells into retinal pigment epithelial cells (RPE) to study the mechanisms of disease and test potential therapies. RP2 protein was undetectable in the RP2 R120X patient cells, suggesting a disease mechanism caused by complete lack of RP2 protein. The RP2 patient fibroblasts and iPSC-derived RPE cells showed phenotypic defects in IFT20 localization, Golgi cohesion and Gβ1 trafficking. These phenotypes were corrected by over-expressing GFP-tagged RP2. Using the translational read-through inducing drugs (TRIDs) G418 and PTC124 (Ataluren), we were able to restore up to 20% of endogenous, full-length RP2 protein in R120X cells. This level of restored RP2 was sufficient to reverse the cellular phenotypic defects observed in both the R120X patient fibroblasts and iPSC-RPE cells. This is the first proof-of-concept study to demonstrate successful read-through and restoration of RP2 function for the R120X nonsense mutation. The ability of the restored RP2 protein level to reverse the observed cellular phenotypes in cells lacking RP2 indicates that translational read-through could be clinically beneficial for patients. PMID:25292197

  7. Molecular Dynamics Simulation and Experimental Study of DNTF on Plasticizing Properties of NC%DNTF 对 NC 塑化特性的分子动力学模拟及实验研究

    Institute of Scientific and Technical Information of China (English)

    孟玲玲; 齐晓飞; 王江宁; 樊学忠

    2015-01-01

    为研究 DNTF 对 CMDB 推进剂力学性能的作用机理,通过分子动力学模拟方法建立了 NC 纯物质和 NC/DNTF 共混物分子模型,研究了 DNTF 对 NC 塑化过程中微观结构的影响,采用拉伸试验研究了 DNTF 对 CMDB推进剂力学性能的影响。结果表明,DNTF 与 NC 分子形成氢键,使 NC 内分子的氢键减弱,NC 分子的刚性降低;加入 DNTF 后,DNTF-CMDB 推进剂的抗拉强度降低、延伸率增加;20℃时延伸率由8.69%增加到33.6%,50℃时延伸率由14.86%增加到45.6%。分子动力学模拟计算结果与拉伸试验结果一致。%To investigate the acting mechanism of 3,4-dinitrofurazanfuroxan (DNTF)on the mechanical properties of CMDB propellants,the molecular models of nitrocellulose (NC)pure substance and NC/ DNTF blends were established by molecular dynamics simulation method.The effects of DNTF on the microstructure of NC in plastici-zing process were studied.The effects of DNTF on the mechanical properties of CMDB propellants were explored using the tensile test.Results show that DNTF and NC molecules form hydrogen bonds,which make the inner-molecule hydrogen bonds for NC weaken and the rigidity of NC molecules reduce.After addition of DNTF in CMDB propellants,the elongation of the DNTF-CMDB propellant increases,while the tensile strength decreases.The elongation increases from 8.69% to 33.6% at 20℃ and increases from 14.86 to 45.6% at 50℃.The results of molecular dynamics simulation are in agreement with those of tensile test.

  8. Surface severe plastic deformation of AISI 304 via conventional shot peening, severe shot peening and repeening

    Energy Technology Data Exchange (ETDEWEB)

    Unal, Okan, E-mail: unalokan78@gmail.com [Mechanical Engineering Department, Bartın University, Bartın 74100 (Turkey); Varol, Remzi [Mechanical Engineering Department, Suleyman Demirel University, Isparta 32200 (Turkey)

    2015-10-01

    Highlights: • CSP and SSP treatments transform austenite to metastable martensite structure. • Nanograin layer thickness after CSP and SSP is 8 μm and 22 μm, respectively. • Shot peening leads to carbon segregation from coarse to nano grain layer. • Repeening is an effective way to reduce surface roughness. - Abstract: Air blast conventional shot peening (CSP), severe shot peening (SSP) and repeening (RP) as a severe plastic deformation applications on AISI 304 austenitic stainless steel is addressed. Shot peened specimens are investigated based on optical, FESEM and digital microscope. The investigations present the austenite transformation to metastable martensite via mechanical twinning due to plastic deformation with high strain rates. It is found that SSP induces thicker nanograin layer with compared to CSP. In XRD studies, the austenite peaks broaden by means of severe shot peening and FWHM increase reveals the grain size reduction below 25 nm regimes on the surface. In EDAX line analysis of CSP specimen, carbon content increase has been detected from deformed layer through the nanocrystalline layer then the content reduces. The carbon segregation takes place due to the energy level distinction between dislocations and Fe−C bonds. 3d contour digital microscope studies and roughness investigations reveal that SSP has deleterious side effect on the surface roughness and surface flatness. However, RP is an effective way to reduce the surface roughness to reasonable values.

  9. Plastic in North Sea Fish

    NARCIS (Netherlands)

    Foekema, E.M.; Gruijter, de C.; Mergia, M.T.; Franeker, van J.A.; Murk, A.J.; Koelmans, A.A.

    2013-01-01

    To quantify the occurrence of ingested plastic in fish species caught at different geographical positions in the North Sea, and to test whether the fish condition is affected by ingestion of plastics, 1203 individual fish of seven common North Sea species were investigated: herring, gray gurnard, wh

  10. The scope of plastic surgery

    African Journals Online (AJOL)

    2013-08-03

    Aug 3, 2013 ... areas of surgery (especially general surgery), plastic surgeons are arguably the .... Who do you feel are experts in laparoscopic surgery? e (general surgeons) a. Maxillofacial .... of pressure sore. ORIF = open reduction internal fixation. ... Plastic versus cosmetic surgery: What's the difference? Plast Reconstr.

  11. New Life for Old Plastics

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Recycling joint venture utilizes innovative technology to reuse plastics Recycling,despite its green connotations,can be a messy business.In China,more than 400,000 companies are engaged in plastic recycling,but 70 percent of them are family enterprises,

  12. Computational strain gradient crystal plasticity

    DEFF Research Database (Denmark)

    Niordson, Christian Frithiof; Kysar, Jeffrey W.

    2014-01-01

    of plane crystal plasticity are studied: pure shear of a single crystal between rigid platens as well as plastic deformation around cylindrical voids in hexagonal close packed and face centered cubic crystals. Effective in-plane constitutive slip parameters for plane strain deformation of specifically...

  13. Architecture of European Plastic Surgery

    NARCIS (Netherlands)

    Nicolai, J. -P. A.; Banic, A.; Molea, G.; Mazzola, R.; Poell, J. G.

    2006-01-01

    The architecture of European Plastic Surgery was published in 1996 [Nicolai JPA, Scuderi N. Plastic surgical Europe in an organogram. Eur J Plast Surg 1996; 19: 253-6.] It is the objective of this paper to update information of that article. Continuing medical education (CME), science, training,

  14. Plastics for corrosion inhibition

    CERN Document Server

    Goldade, Victor A; Makarevich, Anna V; Kestelman, Vladimir N

    2005-01-01

    The development of polymer composites containing inhibitors of metal corrosion is an important endeavour in modern materials science and technology. Corrosion inhibitors can be located in a polymer matrix in the solid, liquid or gaseous phase. This book details the thermodynamic principles for selecting these components, their compatibility and their effectiveness. The various mechanisms of metal protection – barrier, inhibiting and electromechanical – are considered, as are the conflicting requirements placed on the structure of the combined material. Two main classes of inhibited materials (structural and films/coatings) are described in detail. Examples are given of structural plastics used in friction units subjected to mechano-chemical wear and of polymer films/coatings for protecting metal objects against corrosion.

  15. Universal features of amorphous plasticity

    Science.gov (United States)

    Budrikis, Zoe; Castellanos, David Fernandez; Sandfeld, Stefan; Zaiser, Michael; Zapperi, Stefano

    2017-07-01

    Plastic yielding of amorphous solids occurs by power-law distributed deformation avalanches whose universality is still debated. Experiments and molecular dynamics simulations are hampered by limited statistical samples, and although existing stochastic models give precise exponents, they require strong assumptions about fixed deformation directions, at odds with the statistical isotropy of amorphous materials. Here, we introduce a fully tensorial, stochastic mesoscale model for amorphous plasticity that links the statistical physics of plastic yielding to engineering mechanics. It captures the complex shear patterning observed for a wide variety of deformation modes, as well as the avalanche dynamics of plastic flow. Avalanches are described by universal size exponents and scaling functions, avalanche shapes, and local stability distributions, independent of system dimensionality, boundary and loading conditions, and stress state. Our predictions consistently differ from those of mean-field depinning models, providing evidence that plastic yielding is a distinct type of critical phenomenon.

  16. Phenotypic Plasticity and Species Coexistence.

    Science.gov (United States)

    Turcotte, Martin M; Levine, Jonathan M

    2016-10-01

    Ecologists are increasingly interested in predicting how intraspecific variation and changing trait values impact species interactions and community composition. For many traits, much of this variation is caused by phenotypic plasticity, and thus the impact of plasticity on species coexistence deserves robust quantification. Partly due to a lack of sound theoretical expectations, empirical studies make contradictory claims regarding plasticity effects on coexistence. Our critical review of this literature, framed in modern coexistence theory, reveals that plasticity affects species interactions in ways that could impact stabilizing niche differences and competitive asymmetries. However, almost no study integrates these measures to quantify the net effect of plasticity on species coexistence. To address this challenge, we outline novel empirical approaches grounded in modern theory.

  17. Imaging brain plasticity after trauma

    Institute of Scientific and Technical Information of China (English)

    Zhifeng Kou; Armin Iraji

    2014-01-01

    The brain is highly plastic after stroke or epilepsy;however, there is a paucity of brain plasticity investigation after traumatic brain injury (TBI). This mini review summarizes the most recent evidence of brain plasticity in human TBI patients from the perspective of advanced magnetic resonance imaging. Similar to other forms of acquired brain injury, TBI patients also demonstrat-ed both structural reorganization as well as functional compensation by the recruitment of other brain regions. However, the large scale brain network alterations after TBI are still unknown, and the ifeld is still short of proper means on how to guide the choice of TBI rehabilitation or treat-ment plan to promote brain plasticity. The authors also point out the new direction of brain plas-ticity investigation.

  18. Size effects in crystal plasticity

    DEFF Research Database (Denmark)

    Borg, Ulrik

    2007-01-01

    Numerical analyses of plasticity size effects have been carried out for different problems using a developed strain gradient crystal plasticiy theory. The theory employs higher order stresses as work conjugates to slip gradients and uses higher order boundary conditions. Problems on localization...... of plastic flow in a single crystal, grain boundary effects in a bicrystal, and grain size effects in a polycrystal are studied. Single crystals containing micro-scale voids have also been analyzed at different loading conditions with focus on the stress and deformation fields around the voids, on void...... growth and interaction between neighboring voids, and on a comparison between the developed strain gradient crystal plasticity theory and a discrete dislocation plasticity theory. Furthermore, voids and rigid inclusions in isotropic materials have been studied using a strain gradient plasticity theory...

  19. Bending behavior of lapped plastic ehv cables

    Energy Technology Data Exchange (ETDEWEB)

    Morgan, G H; Muller, A C

    1980-01-01

    One of the factors delaying the development of lapped polymeric cables has been their reputed poor bending characteristics. Complementary programs were begun at BNL several years ago to mathematically model the bending of synthetic tape cables and to develop novel plastic tapes designed to have moduli more favorable to bending. A series of bend tests was recently completed to evaluate the bending performance of several tapes developed for use in experimental superconducting cables. The program is discussed and the results of the bend tests are summarized.

  20. Adaptive plasticity model for bucket foundations

    DEFF Research Database (Denmark)

    Ibsen, Lars Bo; Barari, Amin; Larsen, Kim A.

    2014-01-01

    Based on experimental investigations, the literature proposes different methods for modeling the behavior and capacity of foundations subjected to combined loading. Generally, two methods are used to predict the behavior of foundations: traditional approaches and hardening plasticity solutions....... The first method is only capable of determining the capacity of the foundations and not the prepeak behavior. Thus, a new strain-hardening criterion is developed by calibrating failure criteria by employing data from small-scale tests on bucket foundations subjected to static loads. The shape of the yield...

  1. Thermal and catalytic pyrolysis of plastic waste

    Directory of Open Access Journals (Sweden)

    Débora Almeida

    2016-02-01

    Full Text Available Abstract The amount of plastic waste is growing every year and with that comes an environmental concern regarding this problem. Pyrolysis as a tertiary recycling process is presented as a solution. Pyrolysis can be thermal or catalytical and can be performed under different experimental conditions. These conditions affect the type and amount of product obtained. With the pyrolysis process, products can be obtained with high added value, such as fuel oils and feedstock for new products. Zeolites can be used as catalysts in catalytic pyrolysis and influence the final products obtained.

  2. Mechanoelectrochemical behavior and plasticity of magnesium alloys

    Energy Technology Data Exchange (ETDEWEB)

    Eliezer, A.; Gutman, E.M.; Abramov, E.; Aghion, E. [Ben-Gurion Univ. of the Negev, Beersheba (Israel). Dept. of Materials Engineering

    1998-12-31

    The mechanical properties and mechanoelectrochemical effect (the effect of mechanical deformation on the surface electrochemical reactions) were investigated for some Mg-based alloys supposing that aluminum alloying influences them. A simple method of testing mechanoelectrochemical behavior of metals was developed. Potentiostatic polarization measurements on stressed electrode were carried out in chloride electrolyte. The correlation between the mechanoelectrochemical behavior and strain hardening stages is observed during plastic deformation. Maximum mechanoelectrochemical effect is achieved under intense strain hardening in the initial portion of this stage. The experimental observations are explained theoretically. (orig.) 9 refs.

  3. A coupled elasto-plastic-damage mechanical model for marble

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    A profound understanding of the mechanical behaviors of marble is very important for the design and construction of deep diversion tunnels in Jinping II hydropower station.In this paper,a coupled elasto-plastic-damage mechanical model is presented for Jinping marble.Firstly,the experimental investigations on Jinping marble are summarized.Then,based on the framework of continuum damage and plastic theories,a general mechanical model is proposed to predict the mechanical responses of Jinping marble.The proposed model is used to simulate the triaxial compressive tests,and there is a general good agreement between experimental data and numerical predictions in a qualitative manner.The proposed model is able to capture the main features of Jinping marble observed in experiments,such as progressive yielding process,damage induced by plastic distortion,dilation,elastic degradation and stress sensitivity.

  4. Nano-Ceramic Coated Plastics

    Science.gov (United States)

    Cho, Junghyun

    2013-01-01

    Plastic products, due to their durability, safety, and low manufacturing cost, are now rapidly replacing cookware items traditionally made of glass and ceramics. Despite this trend, some still prefer relatively expensive and more fragile ceramic/glassware because plastics can deteriorate over time after exposure to foods, which can generate odors, bad appearance, and/or color change. Nano-ceramic coatings can eliminate these drawbacks while still retaining the advantages of the plastic, since the coating only alters the surface of the plastic. The surface coating adds functionality to the plastics such as self-cleaning and disinfectant capabilities that result from a photocatalytic effect of certain ceramic systems. These ceramic coatings can also provide non-stick surfaces and higher temperature capabilities for the base plastics without resorting to ceramic or glass materials. Titanium dioxide (TiO2) and zinc oxide (ZnO) are the candidates for a nano-ceramic coating to deposit on the plastics or plastic films used in cookware and kitchenware. Both are wide-bandgap semiconductors (3.0 to 3.2 eV for TiO2 and 3.2 to 3.3 eV for ZnO), so they exhibit a photocatalytic property under ultraviolet (UV) light. This will lead to decomposition of organic compounds. Decomposed products can be easily washed off by water, so the use of detergents will be minimal. High-crystalline film with large surface area for the reaction is essential to guarantee good photocatalytic performance of these oxides. Low-temperature processing (nano-ceramic coatings (TiO2, ZnO) on plastic materials (silicone, Teflon, PET, etc.) that can possess both photocatalytic oxide properties and flexible plastic properties. Processing cost is low and it does not require any expensive equipment investment. Processing can be scalable to current manufacturing infrastructure.

  5. Biodegradability of degradable plastic waste.

    Science.gov (United States)

    Agamuthu, P; Faizura, Putri Nadzrul

    2005-04-01

    Plastic waste constitutes the third largest waste volume in Malaysian municipal solid waste (MSW), next to putrescible waste and paper. The plastic component in MSW from Kuala Lumpur averages 24% (by weight), whereas the national mean is about 15%. The 144 waste dumps in the country receive about 95% of the MSW, including plastic waste. The useful life of the landfills is fast diminishing as the plastic waste stays un-degraded for more than 50 years. In this study the compostability of polyethylene and pro-oxidant additive-based environmentally degradable plastics (EDP) was investigated. Linear low-density polyethylene (LLDPE) samples exposed hydrolytically or oxidatively at 60 degrees C showed that the abiotic degradation path was oxidative rather than hydrolytic. There was a weight loss of 8% and the plastic has been oxidized as shown by the additional carbonyl group exhibited in the Fourier transform infra red (FTIR) Spectrum. Oxidation rate seemed to be influenced by the amount of pro-oxidant additive, the chemical structure and morphology of the plastic samples, and the surface area. Composting studies during a 45-day experiment showed that the percentage elongation (reduction) was 20% for McD samples [high-density polyethylene, (HDPE) with 3% additive] and LL samples (LLDPE with 7% additive) and 18% reduction for totally degradable plastic (TDP) samples (HDPE with 3% additive). Lastly, microbial experiments using Pseudomonas aeroginosa on carbon-free media with degradable plastic samples as the sole carbon source, showed confirmatory results. A positive bacterial growth and a weight loss of 2.2% for degraded polyethylene samples were evident to show that the degradable plastic is biodegradable.

  6. Estimation of Eletriptan Hydrobromide in Oral Film Dosage Form by RP-HPLC

    Directory of Open Access Journals (Sweden)

    Pavan Kumar Kothapuvari

    2015-11-01

    Full Text Available A simple, precise, rapid and accurate RP-HPLC method was developed for the percentage drug release estimation of Eletriptan Hydrobromide in oral film dosage form. Eletriptan Hydrobromide is used to treat severe migraine headaches and it’s associated to nausea and sensitivity to light. Eletriptan Hydrobromide oral films were prepared by solvent casting method. It is available in market as conventional tablets (Relpax. An Xterra RP18 (150 × 4.6 with 5 microns particle size and the mobile phase, consisting of KH2PO4 and triethylamine in water adjusting the pH-7.0 with o-phosphoric acid: acetonitrile in ratio of 98:2 v/v & acetonitrile: methanol HPLC Grade (80:20 v/v was used as mobile phase in isocratic mode. The flow rate was 1.0 mL/min and the effluents were monitored at 225 nm. The retention time was 7.0 minutes and the detector response was linear in the concentration of 6.60-99.02µg/mL for Eletriptan Hydrobromide. The respective linear regression equation being Y = 11447 X + 5508 for Eletriptan Hydrobromide. The Limit of Detection (LOD and Limit of Quantification (LOQ were not applicable for dissolution parameter. The method was validated by determining its accuracy, precision, linearity and system suitability. The results of the study showed that the proposed RP-HPLC method is simple, rapid, precise, linear and accurate, which is useful for the routine estimation of percentage drug release of Eletriptan Hydrobromide in oral film dosage form.

  7. An investigation of the plastic fracture of high strength steels. Ph.D. Thesis

    Science.gov (United States)

    Cox, T. B.; Low, J. R., Jr.

    1973-01-01

    Three generally recognized stages of plastic fracture in high strength steels are considered in detail. These stages consist of void initiation, void growth, and void coalescence. A brief review of the existing literature on plastic fracture is included along with an outline of the experimental approach used in the investigation.

  8. Strength of cellulosic fiber/starch acetate composites with variable fiber and plasticizer content

    DEFF Research Database (Denmark)

    Joffe, Roberts; Madsen, Bo; Nättinen, Kalle

    2015-01-01

    In this experimental study, the performance of injection-molded short flax and hemp fibers in plasticized starch acetate were analyzed in terms of strength. Parameters involved in the analysis are a variable fiber and plasticizer content. The measured strength of the composites varies in the rang...

  9. Isomeric state of {sup 80}Y and its role in the rp-process

    Energy Technology Data Exchange (ETDEWEB)

    Novikov, Y.N. [St. Petersburg Nuclear Physics Inst., Gatchina (Russian Federation); Schatz, H.; Dendooven, P.; Beraud, R.; Miehe, C.; Popov, A.V.; Seliverstov, D.M.; Vorobjev, G.K.; Baumann, P.; Borge, M.J.G.; Canchel, G.; Desagne, P.; Emsallem, A.; Huang, W.; Huikari, J.; Jokinen, A.; Knipper, A.; Kolhinen, V.; Nieminen, A.; Oinonen, M.; Penttilae, H.; Peraejaervi, K.; Piqueras, I.; Rinta-Antila, S.; Szerypo, J.; Wang, Y.; Aeystoe, J.

    2003-07-01

    The HIGISOL facility has been used to investigate carefully the isomeric transition 228.5 keV in {sup 80}Y. We have measured the electron internal conversion coefficient for this transition {alpha}{sub K}=0.50{+-}0.07 which gives the value for half-life of ''bare'' isomeric state T{sub 1/2}=6.8{+-}0.5 s. The isomeric state should play an important role in the rp-process calculations. (orig.)

  10. The importance of nuclear masses in the astrophysical rp-process

    CERN Document Server

    Schatz, H

    2006-01-01

    The importance of mass measurements for astrophysical capture processes in general, and for the rp-process in X-ray bursts in particular is discussed. A review of the current uncertainties in the effective lifetimes of the major waiting points 64Ge, 68Se, and 72Kr demonstrates that despite of recent measurements uncertainties are still significant. It is found that mass measurements with an accuracy of the order of 10 keV or better are desirable, and that reaction rate uncertainties play a critical role as well.

  11. Dynamic Critical Behaviour of Wolff's Algorithm for $RP^N$ $\\sigma$-Models

    OpenAIRE

    Caracciolo, S.; Edwards, R. G.; Pelissetto, A.; Sokal, A. D.

    1992-01-01

    We study the performance of a Wolff-type embedding algorithm for $RP^N$ $\\sigma$-models. We find that the algorithm in which we update the embedded Ising model \\`a la Swendsen-Wang has critical slowing-down as $z_\\chi \\approx 1$. If instead we update the Ising spins with a perfect algorithm which at every iteration produces a new independent configuration, we obtain $z_\\chi \\approx 0$. This shows that the Ising embedding encodes well the collective modes of the system, and that the behaviour ...

  12. Nuclear structure theory for the astrophysical rp-process and r-process

    Energy Technology Data Exchange (ETDEWEB)

    Brown, B.A.; Clement, R.; Schatz, H.; Giansiracusa, J.; Richter, W.A.; Hjorth-Jensen, M.; Kratz, K.-L.; Pfeiffer, B.; Walters, W.B

    2003-05-19

    The astrophysical processes of rapid-proton capture and rapid-neutron capture require the knowledge of many nuclear properties which are not known from experiment. I will describe two examples of how theoretical models are used to provide this input. The first of these uses the Hartree-Fock method for displacement energies to obtain the masses of proton-rich nuclei needed for the rp-process. The second uses a model for configuration mixing near {sup 132}Sn to provide Q values and beta-decay lifetimes for the r-process.

  13. Modelling the torsion of thin metal wires by distortion gradient plasticity

    Science.gov (United States)

    Bardella, Lorenzo; Panteghini, Andrea

    2015-05-01

    Under small strains and rotations, we apply a phenomenological higher-order theory of distortion gradient plasticity to the torsion problem, here assumed as a paradigmatic benchmark of small-scale plasticity. Peculiar of the studied theory, proposed about ten years ago by Morton E. Gurtin, is the constitutive inclusion of the plastic spin, affecting both the free energy and the dissipation. In particular, the part of the free energy, called the defect energy, which accounts for Geometrically Necessary Dislocations, is a function of Nye's dislocation density tensor, dependent on the plastic distortion, including the plastic spin. For the specific torsion problem, we implement this distortion gradient plasticity theory into a Finite Element (FE) code characterised by implicit (Backward Euler) time integration, numerically robust and accurate for both viscoplastic and rate-independent material responses. We show that, contrariwise to other higher-order theories of strain gradient plasticity (neglecting the plastic spin), the distortion gradient plasticity can predict some strengthening even if a quadratic defect energy is chosen. On the basis of the results of many FE analyses, concerned with (i) cyclic loading, (ii) switch in the higher-order boundary conditions during monotonic plastic loading, (iii) the use of non-quadratic defect energies, and (iv) the prediction of experimental data, we mainly show that (a) including the plastic spin contribution in a gradient plasticity theory is highly recommendable to model small-scale plasticity, (b) less-than-quadratic defect energies may help in describing the experimental results, but they may lead to anomalous cyclic behaviour, and (c) dissipative (unrecoverable) higher-order finite stresses are responsible for an unexpected mechanical response under non-proportional loading.

  14. RP1L1 variants are associated with a spectrum of inherited retinal diseases including retinitis pigmentosa and occult macular dystrophy.

    Science.gov (United States)

    Davidson, Alice E; Sergouniotis, Panagiotis I; Mackay, Donna S; Wright, Genevieve A; Waseem, Naushin H; Michaelides, Michel; Holder, Graham E; Robson, Anthony G; Moore, Anthony T; Plagnol, Vincent; Webster, Andrew R

    2013-03-01

    In one consanguineous family with retinitis pigmentosa (RP), a condition characterized by progressive visual loss due to retinal degeneration, homozygosity mapping, and candidate gene sequencing suggested a novel locus. Exome sequencing identified a homozygous frameshifting mutation, c.601delG, p.Lys203Argfs*28, in RP1L1 encoding RP 1-like1, a photoreceptor-specific protein. A screen of a further 285 unrelated individuals with autosomal recessive RP identified an additional proband, homozygous for a missense variant, c.1637G>C, p.Ser546Thr, in RP1L1. A distinct retinal disorder, occult macular dystrophy (OCMD) solely affects the central retinal cone photoreceptors and has previously been reported to be associated with variants in the same gene. The association between mutations in RP1L1 and the disorder OCMD was explored by screening a cohort of 28 unrelated individuals with the condition; 10 were found to harbor rare (minor allele frequency ≤0.5% in the 1,000 genomes dataset) heterozygous RP1L1 missense variants. Analysis of family members revealed many unaffected relatives harboring the same variant. Linkage analysis excluded the possibility of a recessive mode of inheritance, and sequencing of RP1, a photoreceptor protein that interacts with RP1L1, excluded a digenic mechanism involving this gene. These findings imply an important and diverse role for RP1L1 in human retinal physiology and disease.

  15. Evidence for a major retinitis pigmentosa locus on 19q13.4 (RP11), and association with a unique bimodal expressivity phenotype

    Energy Technology Data Exchange (ETDEWEB)

    Al-Maghtheh, M.; Vithana, E.; Tarttelin, E.; Evans, K. [Moorfields Eye Hospital, London (United Kingdom)] [and others

    1996-10-01

    Retinitis pigmentosa (RP) is the name given to a heterogeneous group of retinal degenerations mapping to at least 16 loci. The autosomal dominant form (adRP), accounting for {approximately}25% of cases, can be caused by mutations in two genes, rhodopsin and peripherin/RDS, and by at least six other loci identified by linkage analysis. The RP11 locus for adRP has previously been mapped to chromosome 19q13.4 in a large English family. This linkage has been independently confirmed in a Japanese family, and we now report three additional unrelated linked U.K. families, suggesting that this is a major locus for RP. Linkage analysis in the U.K. families refines the RP11 interval to 5 cM between markers D19S180 and AFMc001yb1. All linked families exhibit incomplete penetrance; some obligate gene carriers remain asymptomatic throughout their lives, whereas symptomatic individuals experience night blindness and visual field loss in their teens and are generally registered as blind by their 30s. This {open_quotes}bimodal expressivity{close_quotes} contrasts with the variable-expressivity RP mapping to chromosome 7p (RP9) in another family, which has implications for diagnosis and counseling of RP11 families. These results may also imply that a proportion of sporadic RP, previously assumed to be recessive, might result from mutations at this locus. 27 refs., 3 figs., 1 tab.

  16. International policies to reduce plastic marine pollution from single-use plastics (plastic bags and microbeads): A review.

    Science.gov (United States)

    Xanthos, Dirk; Walker, Tony R

    2017-02-18

    Marine plastic pollution has been a growing concern for decades. Single-use plastics (plastic bags and microbeads) are a significant source of this pollution. Although research outlining environmental, social, and economic impacts of marine plastic pollution is growing, few studies have examined policy and legislative tools to reduce plastic pollution, particularly single-use plastics (plastic bags and microbeads). This paper reviews current international market-based strategies and policies to reduce plastic bags and microbeads. While policies to reduce microbeads began in 2014, interventions for plastic bags began much earlier in 1991. However, few studies have documented or measured the effectiveness of these reduction strategies. Recommendations to further reduce single-use plastic marine pollution include: (i) research to evaluate effectiveness of bans and levies to ensure policies are having positive impacts on marine environments; and (ii) education and outreach to reduce consumption of plastic bags and microbeads at source.

  17. Three novel and the common Arg677Ter RP1 protein truncating mutations causing autosomal dominant retinitis pigmentosa in a Spanish population

    Directory of Open Access Journals (Sweden)

    Antiñolo Guillermo

    2006-04-01

    Full Text Available Abstract Background Retinitis pigmentosa (RP, a clinically and genetically heterogeneous group of retinal degeneration disorders affecting the photoreceptor cells, is one of the leading causes of genetic blindness. Mutations in the photoreceptor-specific gene RP1 account for 3–10% of cases of autosomal dominant RP (adRP. Most of these mutations are clustered in a 500 bp region of exon 4 of RP1. Methods Denaturing gradient gel electrophoresis (DGGE analysis and direct genomic sequencing were used to evaluate the 5' coding region of exon 4 of the RP1 gene for mutations in 150 unrelated index adRP patients. Ophthalmic and electrophysiological examination of RP patients and relatives according to pre-existing protocols were carried out. Results Three novel disease-causing mutations in RP1 were detected: Q686X, K705fsX712 and K722fsX737, predicting truncated proteins. One novel missense mutation, Thr752Met, was detected in one family but the mutation does not co-segregate in the family, thereby excluding this amino acid variation in the protein as a cause of the disease. We found the Arg677Ter mutation, previously reported in other populations, in two independent families, confirming that this mutation is also present in a Spanish population. Conclusion Most of the mutations reported in the RP1 gene associated with adRP are expected to encode mutant truncated proteins that are approximately one third or half of the size of wild type protein. Patients with mutations in RP1 showed mild RP with variability in phenotype severity. We also observed several cases of non-penetrant mutations.

  18. Determination of Gallic acid in Xiaozhiling Tablet by RP-HPLC%RP-HPLC法测定消痔灵片中没食子酸的含量

    Institute of Scientific and Technical Information of China (English)

    秦贻强; 龚勋; 董晓敏

    2012-01-01

    Objective To establish a method for determining the active principlein the Xiaozhiling Tablet, and provide a standard for the quality. Methods A RP-HPLC method was set up to determine the content of Gallic acid in Xiaozhiling Tablet, which was used Sino Chrom C18 (4.6 mmx250 mm, 5 μm) column, and methanol-water-Phosphoric acid (6:94:0.2) as the mobile phase, the UV detection wavelength was 266 nm, with a flow rate of 1.0 mL/min at (25±1)℃. Results A good linear was obtained in the range of 18~48 g/mL, and the average recovery was 99.75%, RSD was 0.97%. Conclusion The method is simple, rapid, accurate, and with good reproducibility for the determination of Gallic acid in Xiaozhiling Tablet.%目的 建立消痔灵片有效成分含量测定的方法,为其质量标准的制订提供依据.方法 采用RP-HPLC法测定,以没食子酸为对照品,色谱柱:Sino Chrom ODS-APC18(250 mm × 4.6 mm,5 μm),流动相:甲醇-水-磷酸(6∶94∶0.2),检测波长:266 nm,流速:1.0 mL/min,柱温:(25±1)℃.结果 没食子酸在18~48 μg/mL范围内呈良好的线性关系(r = 0.999 1),平均回收率为99.75%,RSD = 0.97%.结论本方法准确,简便,灵敏度高,可用于消痔灵片中没食子酸的含量测定并有效评价该制剂的质量.

  19. Successively refined models for crack tip plasticity in polymer blends

    NARCIS (Netherlands)

    Pijnenburg, KGW; Seelig, T; van der Giessen, E

    2005-01-01

    This paper is concerned with a comparative study of different, partly complementary micromechanical models for crack tip plasticity in polymer-rubber blends. It is experimentally well established that interspersion of micron-scale rubber particles into a polymer matrix can lead to a significantly en

  20. A Nonvolume Preserving Plasticity Theory with Applications to Powder Metallurgy

    Science.gov (United States)

    Cassenti, B. N.

    1983-01-01

    A plasticity theory has been developed to predict the mechanical response of powder metals during hot isostatic pressing. The theory parameters were obtained through an experimental program consisting of hydrostatic pressure tests, uniaxial compression and uniaxial tension tests. A nonlinear finite element code was modified to include the theory and the results of themodified code compared favorably to the results from a verification experiment.

  1. Simulation study of element plastic migration from radiometric measurements

    Energy Technology Data Exchange (ETDEWEB)

    Rosa, Faena M.L.; Manzoli, Jose Eduardo; Saiki, Mitiko [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Soares, Eufemia Paez [Escola SENAI Fundacao Zerrenner, Sao Paulo, SP (Brazil)], E-mail: eufemia@sp.senai.br

    2007-07-01

    Element migration from plastic packaging to either foodstuffs or medicine is a serious public health. Many conventional experimental techniques such as chromatography-mass spectrometry, atomic absorption spectroscopy, inductively coupled plasma spectroscopy or calorimetric methods are used to measure total and specific migration of components from plastic packaging. The radiometric method is also used to measure the element migration. In this study a numerical technique was employed to simulate the experimental migration results obtained from measurements of elements from dairy product polymeric packages into 3% acetic acid solution which is a normative food simulant. This numerical technique can be used as complementary tool for the experimental measurements, allowing for a better understanding of the diffusion process and to estimate element migration situations not experimentally measured. (author)

  2. Non-adaptive plasticity potentiates rapid adaptive evolution of gene expression in nature.

    Science.gov (United States)

    Ghalambor, Cameron K; Hoke, Kim L; Ruell, Emily W; Fischer, Eva K; Reznick, David N; Hughes, Kimberly A

    2015-09-17

    Phenotypic plasticity is the capacity for an individual genotype to produce different phenotypes in response to environmental variation. Most traits are plastic, but the degree to which plasticity is adaptive or non-adaptive depends on whether environmentally induced phenotypes are closer or further away from the local optimum. Existing theories make conflicting predictions about whether plasticity constrains or facilitates adaptive evolution. Debate persists because few empirical studies have tested the relationship between initial plasticity and subsequent adaptive evolution in natural populations. Here we show that the direction of plasticity in gene expression is generally opposite to the direction of adaptive evolution. We experimentally transplanted Trinidadian guppies (Poecilia reticulata) adapted to living with cichlid predators to cichlid-free streams, and tested for evolutionary divergence in brain gene expression patterns after three to four generations. We find 135 transcripts that evolved parallel changes in expression within the replicated introduction populations. These changes are in the same direction exhibited in a native cichlid-free population, suggesting rapid adaptive evolution. We find 89% of these transcripts exhibited non-adaptive plastic changes in expression when the source population was reared in the absence of predators, as they are in the opposite direction to the evolved changes. By contrast, the remaining transcripts exhibiting adaptive plasticity show reduced population divergence. Furthermore, the most plastic transcripts in the source population evolved reduced plasticity in the introduction populations, suggesting strong selection against non-adaptive plasticity. These results support models predicting that adaptive plasticity constrains evolution, whereas non-adaptive plasticity potentiates evolution by increasing the strength of directional selection. The role of non-adaptive plasticity in evolution has received relatively

  3. Phenotypic plasticity, costs of phenotypes, and costs of plasticity

    DEFF Research Database (Denmark)

    Callahan, Hilary S; Maughan, Heather; Steiner, Uli

    2008-01-01

    Why are some traits constitutive and others inducible? The term costs often appears in work addressing this issue but may be ambiguously defined. This review distinguishes two conceptually distinct types of costs: phenotypic costs and plasticity costs. Phenotypic costs are assessed from patterns...... of covariation, typically between a focal trait and a separate trait relevant to fitness. Plasticity costs, separable from phenotypic costs, are gauged by comparing the fitness of genotypes with equivalent phenotypes within two environments but differing in plasticity and fitness. Subtleties associated with both...... types of costs are illustrated by a body of work addressing predator-induced plasticity. Such subtleties, and potential interplay between the two types of costs, have also been addressed, often in studies involving genetic model organisms. In some instances, investigators have pinpointed the mechanistic...

  4. RP-HPLC法分离异黄酮中移动相条件的优化%Optimum of Mobile Phase Condition for Resolving Isoflavones in RP-HPLC

    Institute of Scientific and Technical Information of China (English)

    郑金珠; 盧敬昊

    2007-01-01

    In reversed-phase high performance liquid chromatography (RP-HPLC),the mobile phase condition for separating eight isoflavones (daidzin,glycitin,genistin,6'-o-acetyl daidzin,6'-o-malonyl genistin,daidzein,glycitein and genistein) was optimized using the HCI (High-Purity Separation Laboratory,Department of Chemical Engineering,Inha University) program software.The optimum composition of mobile phase for the separation of the eight isoflavones was obtained.The elution profiles were calculated by the plate theory based on the equations of retention factor,In k=A+BF+CF2,where F Was the volume percentage of acetonitrile with 0.1% acetic acid (AA).The first mobile phase composition was water with 0.1% AA/acetonitrile with 0.1% AA (88%/12%,by volume),followed at 9min later by the second composition of mobile phase which was step-changed to 85%/15%,at 19min by the third composition which was step-changed to 73%/27%,at 30min when it was changed to 65%/35% and finally it was maintained in isocratic mode to the end of the run time at 50min.Although,using step gradient mode to separate the isoflavones,the calculated and experimented data were not achieved very good agwement,we could estimate the closed retention time before experiment.And the agreement between the experimental data and the calculated values was relatively good using isocratic separation for eight isoflavones,but the retention time is very long.

  5. Biodegradable plastics from renewable sources.

    Science.gov (United States)

    Flieger, M; Kantorová, M; Prell, A; Rezanka, T; Votruba, J

    2003-01-01

    Plastic waste disposal is a huge ecotechnological problem and one of the approaches to solving this problem is the development of biodegradable plastics. This review summarizes data on their use, biodegradability, commercial reliability and production from renewable resources. Some commercially successful biodegradable plastics are based on chemical synthesis (i.e. polyglycolic acid, polylactic acid, polycaprolactone, and polyvinyl alcohol). Others are products of microbial fermentations (i.e. polyesters and neutral polysaccharides) or are prepared from chemically modified natural products (e.g., starch, cellulose, chitin or soy protein).

  6. Plastics recycling: challenges and opportunities

    OpenAIRE

    Hopewell, Jefferson; Dvorak, Robert; Kosior, Edward

    2009-01-01

    Plastics are inexpensive, lightweight and durable materials, which can readily be moulded into a variety of products that find use in a wide range of applications. As a consequence, the production of plastics has increased markedly over the last 60 years. However, current levels of their usage and disposal generate several environmental problems. Around 4 per cent of world oil and gas production, a non-renewable resource, is used as feedstock for plastics and a further 3–4% is expended to pro...

  7. Circadian Regulation of Synaptic Plasticity

    Directory of Open Access Journals (Sweden)

    Marcos G. Frank

    2016-07-01

    Full Text Available Circadian rhythms refer to oscillations in biological processes with a period of approximately 24 h. In addition to the sleep/wake cycle, there are circadian rhythms in metabolism, body temperature, hormone output, organ function and gene expression. There is also evidence of circadian rhythms in synaptic plasticity, in some cases driven by a master central clock and in other cases by peripheral clocks. In this article, I review the evidence for circadian influences on synaptic plasticity. I also discuss ways to disentangle the effects of brain state and rhythms on synaptic plasticity.

  8. PLASMA GASIFICATION OF WASTE PLASTICS

    Directory of Open Access Journals (Sweden)

    Tadeusz Mączka

    2013-01-01

    Full Text Available The article presents the process of obtaining liquid fuels and fuel gas in the process of plasma processing of organic materials, including waste plastics. The concept of plasma pyrolysis of plastics was presented and on its basis a prototype installation was developed. The article describes a general rule of operating the installation and its elements in the process and basic operation parameters determined during its start-up. Initial results of processing plastics and the directions further investigations are also discussed. The effect of the research is to be the design of effective technology of obtaining fuels from gasification/pyrolysis of organic waste and biomass.

  9. Frequency dependent changes in NMDAR-dependent synaptic plasticity

    Directory of Open Access Journals (Sweden)

    Arvind eKumar

    2011-09-01

    Full Text Available The NMDAR-dependent synaptic plasticity is thought to mediate several forms of learning, and can be induced by spike trains containing a small number of spikes occurring with varying rates and timing, as well as with oscillations. We computed the influence of these variables on the plasticity induced at a single NMDAR containing synapse using a reduced model that was analytically tractable, and these findings were confirmed using detailed, multi-compartment model. In addition to explaining diverse experimental results about the rate and timing dependence of synaptic plasticity, the model made several novel and testable predictions. We found that there was a preferred frequency for inducing long-term potentiation (LTP such that higher frequency stimuli induced lesser LTP, decreasing as 1/f when the number of spikes in the stimulus was kept fixed. Among other things, the preferred frequency for inducing LTP varied as a function of the distance of the synapse from the soma. In fact, same stimulation frequencies could induce LTP or LTD depending on the dendritic location of the synapse. Next, we found that rhythmic stimuli induced greater plasticity then irregular stimuli. Furthermore, brief bursts of spikes significantly expanded the timing dependence of plasticity. Finally, we found that in the ~5-15Hz frequency range both rate- and timing-dependent plasticity mechanisms work synergistically to render the synaptic plasticity most sensitive to spike-timing. These findings provide computational evidence that oscillations can have a profound influence on the plasticity of an NMDAR-dependent synapse, and show a novel role for the dendritic morphology in this process.

  10. Oil sorbents from plastic wastes and polymers: A review.

    Science.gov (United States)

    Saleem, Junaid; Adil Riaz, Muhammad; Gordon, McKay

    2018-01-05

    A large volume of the waste produced across the world is composed of polymers from plastic wastes such as polyethylene (HDPE or LDPE), polypropylene (PP), and polyethylene terephthalate (PET) amongst others. For years, environmentalists have been looking for various ways to overcome the problems of such large quantities of plastic wastes being disposed of into landfill sites. On the other hand, the usage of synthetic polymers as oil sorbents in particular, polyolefins, including polypropylene (PP) and polyethylene (PE) have been reported. In recent years, the idea of using plastic wastes as the feed for the production of oil sorbents has gained momentum. However, the studies undertaking such feasibility are rather scattered. This review paper is the first of its kind reporting, compiling and reviewing these various processes. The production of an oil sorbent from plastic wastes is being seen to be satisfactorily achievable through a variety of methods Nevertheless, much work needs to be done regarding further investigation of the numerous parameters influencing production yields and sorbent qualities. For example, differences in results are seen due to varying operating conditions, experimental setups, and virgin or waste plastics being used as feeds. The field of producing oil sorbents from plastic wastes is still very open for further research, and seems to be a promising route for both waste reduction, and the synthesis of value-added products such as oil sorbents. In this review, the research related to the production of various oil sorbents based on plastics (plastic waste and virgin polymer) has been discussed. Further oil sorbent efficiency in terms of oil sorption capacity has been described. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Replacing fossil based plastic performance products by bio-based plastic products-Technical feasibility.

    Science.gov (United States)

    van den Oever, Martien; Molenveld, Karin

    2017-07-25

    Larger scale market introduction of new bio-based products requires a clear advantage regarding sustainability, as well as an adequate techno-economic positioning relative to fossil based products. In a previous paper [Broeren et al., 2016], LCA results per kg and per functionality equivalent of bio-based plastics were presented, together with economic considerations. The present paper discusses the mechanical and thermal properties of a range of commercially available bio-based plastics based on polylactic acid (PLA), cellulose esters, starch and polyamides, and the feasibility of replacing fossil-based counterparts based on performance. The evaluation is approached from an end user perspective. First, potentially suitable bio-based plastics are selected based on manufacturers' specifications in technical data sheets, then a first experimental evaluation is performed on injection moulded ISO specimens, and finally a further selection of plastics is tested on large 50×70cm panels. This technical feasibility study indicates that so far bio-based plastics do not completely match the properties of high performance materials like flame retardant V-0 PC/ABS blends used in electronic devices. The performance gap is being decreased by the development of stereocomplex PLA and hybrid PLA blends with polycarbonate, which offer clearly improved properties with respect to maximum usage temperature and toughness. In addition, several materials meet the V-0 flammability requirements needed in specific durable applications. On the other hand, improving these properties so far has negative consequences for the bio-based content. This study also shows that replacement of bulk polymers like PS is feasible using PLA compounds with a bio-based content as high as 85%.

  12. Recycling of Reinforced Plastics

    Science.gov (United States)

    Adams, R. D.; Collins, Andrew; Cooper, Duncan; Wingfield-Digby, Mark; Watts-Farmer, Archibald; Laurence, Anna; Patel, Kayur; Stevens, Mark; Watkins, Rhodri

    2014-02-01

    This work has shown is that it is possible to recycle continuous and short fibre reinforced thermosetting resins while keeping almost the whole of the original material, both fibres and matrix, within the recyclate. By splitting, crushing hot or cold, and hot forming, it is possible to create a recyclable material, which we designate a Remat, which can then be used to remanufacture other shapes, examples of plates and tubes being demonstrated. Not only can remanufacturing be done, but it has been shown that over 50 % of the original mechanical properties, such as the E modulus, tensile strength, and interlaminar shear strength, can be retained. Four different forms of composite were investigated, a random mat Glass Fibre Reinforced Plastic (GFRP) bathroom component and boat hull, woven glass and carbon fibre cloth impregnated with an epoxy resin, and unidirectional carbon fibre pre-preg. One of the main factors found to affect composite recyclability was the type of resin matrix used in the composite. Thermoset resins tested were shown to have a temperature range around the Glass Transition Temperature (Tg) where they exhibit ductile behaviour, hence aiding reforming of the material. The high-grade carbon fibre prepreg was found to be less easy to recycle than the woven of random fibre laminates. One method of remanufacturing was by heating the Remat to above its glass transition temperature, bending it to shape, and then cooling it. However, unless precautions are taken, the geometric form may revert. This does not happen with the crushed material.

  13. Sensitivity of Type I X-Ray Bursts to rp-Process Reaction Rates

    CERN Document Server

    Amthor, A M; Heger, A; Sakharuk, A; Schatz, H; Smith, K; Galaviz, Daniel; Heger, Alexander; Sakharuk, Alexander; Schatz, Hendrik; Smith, Karl

    2006-01-01

    First steps have been taken in a more comprehensive study of the dependence of observables in Type I X-ray bursts on uncertain (p,gamma) reaction rates along the rp-process path. We use the multizone hydrodynamics code KEPLER which implicitly couples a full nuclear reaction network of more than 1000 isotopes, as needed, to follow structure and evolution of the X-ray burst layer and its ashes. This allows us to incorporate the full rp-process network, including all relevant nuclear reactions, and individually study changes in the X-ray burst light curves when modifying selected key nuclear reaction rates. In this work we considered all possible proton captures to nuclei with 10 < Z < 28 and N <= Z. When varying individual reaction rates within a symmetric full width uncertainty of a factor of 10000, early results for some rates show changes in the burst light curve as large as 10 percent of peak luminosity. This is very large compared to the current sensitivity of X-ray observations. More precise reac...

  14. RP-HPLC determination of recombinant human interferon omega in the Pichia pastoris fermentation broth.

    Science.gov (United States)

    Liu, Hong; Pan, Hong-Chun; Peng, Li; Cai, Shao-Xi

    2005-07-15

    A rapid and valid reversed-phase high performance liquid chromatography (RP-HPLC) method for determination of recombinant human interferon omega (rhIFNomega) in the yeast Pichia pastoris fermentation broth was developed. The method is based on the hydrophobicity of rhIFNomega followed by RP-HPLC separation with UV detection. The chromatography analysis was performed on EC 250/4 NUCLEOSIL 300-5 C18 (250 mm x 4 mm i.d., 300 A, with a particle size of 5 microm) column. The compositions of the mobile phase A and B were 999:1 (v/v) water/TFA and 999:1 (v/v) acetonitrile/TFA at a flow rate of 1.0 ml min(-1). Detection was done by spectrophotometry at 280 nm and the column temperature was 30+/-1 degrees C. Calibration curve was linear (r=0.9986, n=7) in the range of 0.074-0.555 mg ml(-1) for rhIFNomega and the regression equation was y=2.02 x 10(6)x-1.27 x 10(5). Limit of detection for rhIFNomega was 0.053 mg ml(-1). The values of R.S.D. (%) of intra-day and inter-day precision were recovery rate of recovery experiment were <1.23 (n=3) and 97.97%.

  15. RP-HPLC METHOD FOR ESTIMATION OF QUETIAPINE HEMI FUMARATE IN TABLET DOSAGE FORM

    Directory of Open Access Journals (Sweden)

    Mohite Mukesh. T

    2013-08-01

    Full Text Available A simple, sensitive, rapid, robust and reproducible method for the determination of Quetiapine Hemi Fumarate (QHF in bulk and Pharmaceutical Formulation (Tablets was developed using Reverse Phase High Performance Liquid Chromatographic method (RP-HPLC. The RP-HPLC analysis was performed isocratically on XTERRA C18 (4.6 X 150 mm, analytical column using a mobile phase consisting of Acetonitrile and methanol in the ratio of 60 : 40 v / v, with a flow rate of 1 ml / min. The analyte was monitored with UV detector at 290 nm. The developed method Quetiapine hemi fumarate elutes at a run time of 10 minutes. The proposed method is having linearity in the concentration range from 20 to 100 μg / mL of Quetiapine hemi fumarate. The present method was validated with respect to system suitability, linearity, precision, limit of detection (LOD and limit of quantification (LOQ, accuracy (recovery, and robustness as per ICH Guidelines. The proposed method can be readily utilized for bulk drug and pharmaceutical formulations.

  16. Se-68 rp-process waiting point and X-ray bursts

    Science.gov (United States)

    Del Santo, M.; Schatz, H.; Lorusso, G.; Crawford, H.; Grinyer, G. F.; Meisel, Z.; Becerril, A.; Montes, F.; Pereira, J.; Smith, K.; George, S.; Bazin, D.; Mantica, P.

    2011-04-01

    The x-ray light curve of astrophysical X-ray bursts and the composition of their nuclear ashes are shaped by the effective half-life of Se-68, a rare neutron deficient isotope near the proton drip line and a waiting point in the rapid proton capture process (rp-process). We addressed the nuclear physics uncertainty in the Se-68 half-life by studying the beta-delayed particle emission of Kr-69. The experiment was performed at the National Superconducting Cyclotron Laboratory (NSCL). The rare isotope beam was produced by fragmentation of a Kr-78 primary beam, separated using the A1900 and Radio Frequency Fragment Separator, and sent to the Beta Counting Station (BCS). The remaining fragments were implanted into a 500 micron double-sided-Si-strip-detector (DSSD) to detect charged particles (fast electrons and protons) following beta decay. The measured decay curve and delayed proton spectrum will be presented and the possible implications on the energy production in X-ray bursts and mass flow along the rp-process path in the A ~ 70 region will be discussed. This work was supported in part by the National Science Foundation.

  17. Subunit Characteristics of Pig Pancreas Ferritin Revealed by MALDI-TOF MS and RP-HPLC

    Institute of Scientific and Technical Information of China (English)

    HUANG Lin; LIN Zhi-cao; LIN Qing; LUO Lian-zhong; HUANG He-qing

    2008-01-01

    Pig pancreas ferritin(PPF) was purified by ultra-centrifugation,ion-exchange chromatography,and native gradient polyacrylamide gel electrophoresis(PAGENG).Sodium dodecyl sulfate(SDS)-PAGE indicates that PPF consists of two subunit types,namely,H(21000) and L(19000) subunits,and its core shows an average element composition of 1698 Fe3+ and 179 phosphate molecules within the hollow shell,giving a 9.5:1 ratio of Fe3+ to phosphate.An off line approach combining reversed-phase high-performance liquid chromatography(RP-HPLC) with matrix-assisted laser desorption ionization time of flight mass speetrometry(MALDI-TOF MS) made the decomposition of PPF shell into H and L subunits for the analysis of mass spectrometry(MS),giving molecular weights of both H(21014.4) and L(18319.9)subunits.Both subunit types were further identified by an approach combining peptide mass fingerprint(PMF) with database search.A ratio of IH to 2L subunits in PPF was determined by SDS-PAGE,RP-HPLC,and MALDI-TOF MS,respectively.It is well known that the non-covalent interaction of L-L or H-L subunits is stronger than that of H-H subunits in PPF,which may be further used to explain the unclear physiological function between H and L subunits in PPF.

  18. Determination of Quinine in Cosmetics by RP-HPLC%RP-HPLC法检测化妆品中奎宁的含量

    Institute of Scientific and Technical Information of China (English)

    陈志蓉; 刘洋; 张鹏祥; 赵华

    2011-01-01

    目的 对化妆品中奎宁的含量进行定量检测.方法采用RP-HPLC法,色谱柱为Waters sunfire-C18柱,样品经甲醇超声,以甲醇-0.01mol·L-1(NH4)2HPO (90 ∶ 10,体积比)为流动相,流速为1.0mL·min-1,检测波长为328nm,柱温为30℃,进样量为20μL.结果在此条件下,奎宁在1.0~200μg·mL-1范围内线性良好,r=0.9999,回收率在98.6%~100.4%,RSD=0.29%.结论该方法简单易行,能够快速对化妆品中奎宁含量进行定量,杂质干扰小,回收率高,重复性好.

  19. Determination of xanthohumol in Hops (Humunus lupulus L.)by RP-HPLC%RP-HPLC法测定酒花中的黄腐酚

    Institute of Scientific and Technical Information of China (English)

    王宁; 陶冠军; 秦昉; 单连菊; 李崎

    2009-01-01

    建立了反相高效液相色谱法(RP-HPLC)检测酒花中黄腐酚含量的方法.选用色谱柱Zorbax Eclipse XDB-C18柱(250mm×4.6mm,5μm),以甲醇和0.2%甲酸水溶液为流动相进行梯度洗脱.枉温25℃,流速0.5mL/min,检测波长370nm.在此条件下,黄腐酚得到很好分离,在1.13~113mg/L范围内线性关系良好,R2=0.9992,外加标回收率在95.05%~104.03%之间,RSD=2.71%.该方法可以简便、准确地测定酒花中黄腐酚的含量.

  20. RP-HPLC法测定布洛芬离子导入凝胶剂的含量%Determination of Ibuprofen in Ionphoretic Gel by RP-HPLC

    Institute of Scientific and Technical Information of China (English)

    陈莉; 张莉; 李亚; 齐刚

    2007-01-01

    目的 建立一种测定离子导入凝胶剂中布洛芬含量的高效液相色谱法.方法 采用反相高效液相色谱(RP-HPLC)法,以Shim-packVP-0DS柱(4.6 mm×150 mm,5 μm)作分析柱,流动相为甲醇-水-磷酸(75∶25∶0.8,v/v/v),流速1.0 ml/min.柱箱温度40℃,检测波长为264 nm.结果 本法的日内RSD为0.35%,日间RSD为0.68%,平均回收率为100.4%.标准曲线在10~00 μg·ml-1浓度范围内,呈现良好的线性关系(r=0.999 3).结论 该法用于布洛芬离子导入凝胶剂的含量测定,快速、准确、可行.

  1. Temporal and tissue specific regulation of RP-associated splicing factor genes PRPF3, PRPF31 and PRPC8--implications in the pathogenesis of RP.

    Directory of Open Access Journals (Sweden)

    Huibi Cao

    Full Text Available BACKGROUND: Genetic mutations in several ubiquitously expressed RNA splicing genes such as PRPF3, PRP31 and PRPC8, have been found to cause retina-specific diseases in humans. To understand this intriguing phenomenon, most studies have been focused on testing two major hypotheses. One hypothesis assumes that these mutations interrupt retina-specific interactions that are important for RNA splicing, implying that there are specific components in the retina interacting with these splicing factors. The second hypothesis suggests that these mutations have only a mild effect on the protein function and thus affect only the metabolically highly active cells such as retinal photoreceptors. METHODOLOGY/PRINCIPAL FINDINGS: We examined the second hypothesis using the PRPF3 gene as an example. We analyzed the spatial and temporal expression of the PRPF3 gene in mice and found that it is highly expressed in retinal cells relative to other tissues and its expression is developmentally regulated. In addition, we also found that PRP31 and PRPC8 as well as snRNAs are highly expressed in retinal cells. CONCLUSIONS/SIGNIFICANCE: Our data suggest that the retina requires a relatively high level of RNA splicing activity for optimal tissue-specific physiological function. Because the RP18 mutation has neither a debilitating nor acute effect on protein function, we suggest that retinal degeneration is the accumulative effect of decades of suboptimal RNA splicing due to the mildly impaired protein.

  2. RP-HPLC测定枸骨叶中羽扇豆醇的含量%Quantitative analysis of lupeol in leaves of Ilex cornuta by RP-HPLC

    Institute of Scientific and Technical Information of China (English)

    李颜; 吴弢; 王峥涛; 史薇娜; 郭澄

    2008-01-01

    目的:建立RP-HPLC法测定枸骨叶中羽扇豆醇含量的方法,为枸骨叶的质量分析和评价提供科学依据.方法:采用Aglent zorbax ODS柱(4.6 mm×150 mm,5 μm),柱温为25℃,乙腈-水(8:2)为流动相,在流速1.0mL·min-1和紫外检测波长210 nm下进样20μL对枸骨叶甲醇提取物进行HPLC分析.结果:羽扇豆醇在0.25~12.7μg(r=0.999 8)呈良好的线性关系,平均加样回收率为100.2%(RSD4.3%).结论:本方法简便,重复性好,为评价枸骨叶药材的质量提供科学依据.

  3. RP - HPLC determination of amygdalin in Semen Pruni%RP-HPLC法测定郁李仁中苦杏仁苷含量

    Institute of Scientific and Technical Information of China (English)

    霍琳; 陈晓辉; 王鹏; 毕开顺

    2009-01-01

    目的:建立RP-HPLC法测定不同产地、不同种属郁李仁苦杏仁苷含量.方法:采用Kmmasil C_(18)柱(5μm,250×4.6mm);以乙腈-水(12:88)为流动相,流速1.0 mL·min~(-1);检测波长210 nm;柱温35℃.结果:苦杏仁苷的线性范围为5.040~80.6μg.mL~(-1)(r-0.9999);平均回收率(n-9)为99.8%.结论:本法简便,结果准确,重复性好,可作为测定不同种属郁李仁药材中苦杏仁苷含量的方法.

  4. Plastic theory for the multi-crystal metals-From infinitesimal deformation to finite deformation

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Multi-crystal metals have the property of volume conservation in the plastic state. In the infinitesimal deformation plasticity the strain tensor can be split into a deviator part and a volumetric part. The vanishing of the first variant of the strain tensor is equivalent to the volume conservation. Furthermore, the split of the strain into an elastic part and a plastic part is also adopted widely. The flow rule is thus established. These two splits are not confirmed in the finite deformation plasticity. The plasticity criterion and the flow rule are thus facing great challenge. There are various definitions of strain measures in the finite deformation theory. Though the choosing of strain measure is arbitrary in the elastic problem, it is strongly restricted in the plastic problem. By theoretical and experimental studies, it is shown that the logarithmic strain is the only suitable strain measure in the metal forming problem.

  5. Determination of Strychnine in Nux Vomica with Methods of NP-HPLC and RP-HPLC%NP-HPLC与RP-HPLC两种方法测定制马钱子中士的宁含量

    Institute of Scientific and Technical Information of China (English)

    蔡锡潮; 龚又明

    2008-01-01

    目的 比较NP-HPLC与RP-HPLC两种测定制马钱子中士的宁含量的方法.方法 按照2000版和2005版,采用NP-HPLC与KP-HPLC两种方法.结果 加样回收率考察中NP-HPLC法平均回收率为97.16%,RSD=0.71%(n=6);RP-HPLC法平均回收率为98.13%,RSD=0.45%(n=6).结论 此二种方法都准确可靠,RP-HPLC法更为合适.

  6. 3-D Experimental Fracture Analysis at High Temperature

    Energy Technology Data Exchange (ETDEWEB)

    John H. Jackson; Albert S. Kobayashi

    2001-09-14

    T*e, which is an elastic-plastic fracture parameter based on incremental theory of plasticity, was determined numerically and experimentally. The T*e integral of a tunneling crack in 2024-T3 aluminum, three point bend specimen was obtained through a hybrid analysis of moire interferometry and 3-D elastic-plastic finite element analysis. The results were verified by the good agreement between the experimentally and numerically determined T*e on the specimen surface.

  7. Determination of aliskiren in tablet dosage forms by a validated stability-indicating RP-LC method.

    Science.gov (United States)

    Wrasse-Sangoi, M; Sangoi, M S; Oliveira, P R; Secretti, L T; Rolim, C M B

    2011-02-01

    A reversed-phase liquid chromatography (RP-LC) method is validated for the determination of aliskiren in tablet dosage form. The LC method is carried out on a Waters XBridge C(18) column (150 × 4.6 mm i.d.), maintained at 25°C. The mobile phase consisted of acetonitrile:water (95:5, v/v)/phosphoric acid (25 mM, pH 3.0) (40:60, v/v), run at a flow rate of 1.0 mL/min, with photodiode array detector set at 229 nm. The chromatographic separation is obtained with aliskiren retention time of 3.68 min, and it is linear in the range of 10-300 μg/mL (r = 0.9999). The limits of detection and quantitation are 2.38 and 7.93 μg/mL, respectively. The specificity and stability-indicating capability of the method are proven through degradation studies, which also showed that there is no interference of the formulation excipients, showing that peak is free from any coeluting peak. The method showed adequate precision, with a relative standard deviation (RSD) values lower than 0.92%. Good values of accuracy were also obtained, with a mean value of 99.55%. Experimental design is used during validation to calculate method robustness. The proposed method is applied for the analysis of the tablet dosage forms, contributing to improve the quality control and to assure the therapeutic efficacy.

  8. Plasticity and creep of metals

    CERN Document Server

    Rusinko, Andrew

    2011-01-01

    Here is a systematic presentation of the postulates, theorems and principles of mathematical theories of plasticity and creep in metals, and their applications. Special attention is paid to analysis of the advantages and shortcomings of the classical theories.

  9. American Society of Plastic Surgeons

    Science.gov (United States)

    ... PRS PRS GO PSN PSEN GRAFT Contact Us Cosmetic Surgery New procedures and advanced technologies offer plastic surgery ... David Berman MD 14 Pidgeon Hill Drive Berman Cosmetic Surgery & S... Sterling, VA 20165 Website Franklin Richards MD Suite ...

  10. Plastic deformation of nanocrystalline nickel

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    A high-resolution electron microscopy study has uncovered the plastic behavior of accommodating large strains in nanocrystalline (NC) Ni subject to cold rolling at liquid nitrogen temperature. The activation of grain-boundary-mediated-plasticity is evidenced in NC-Ni, including twinning and formation of stacking fault via partial dislocation slips from the grain boundary. The formation and storage of 60? full dislocations are observed inside NC-grains. The grain/twin boundaries act as the barriers of dislocation slips, leading to dislocation pile-up, severe lattice distortion, and formation of sub-grain boundary. The vicinity of grain/twin boundary is where defects preferentially accumulate and likely the favorable place for onset of plastic deformation. The present results indicate the heterogeneous and multiple natures of accommodating plastic strains in NC-grains.

  11. Plastic deformation of nanocrystalline nickel

    Institute of Scientific and Technical Information of China (English)

    WU XiaoLei

    2009-01-01

    A high-resolution electron microscopy study has uncovered the plastic behavior of accommodating large strains in nanocrystalline(NC)Ni subject to cold rolling at liquid nitrogen temperature.The acti vation of grain-boundary-mediated-plasticity is evidenced in NC-Ni,including twinning and formation of stacking fault via partial dislocation slips from the grain boundary.The formation and storage of 60° full dislocations are observed inside NC-grains.The grain/twin boundaries act as the barriers of dislocation slips,leading to dislocation pile-up,severe lattice distortion,and formation of sub-grain boundary.The vicinity of grain/twin boundary is where defects preferentially accumulate and likely the favorable place for onset of plastic deformation.The present results indicate the heterogeneous and multiple natures of accommodating plastic strains in NC-grains.

  12. Globally Oriented Chinese Plastics Industry

    Institute of Scientific and Technical Information of China (English)

    Liao Zhengpin

    2004-01-01

    @@ Through continued endeavor and persistent opening to the whole world the Chinese plastics industry has been developed into a comprehensive industrial system that forms the basic material industries side by side with the steel, cement and the timber industry.

  13. Computational materials science: Nanoscale plasticity

    DEFF Research Database (Denmark)

    Jacobsen, Karsten Wedel; Schiøtz, Jakob

    2002-01-01

    How does plastic deformation of polycrystalline materials with grain sizes less than 100 nm look at the atomic scale? A large-scale molecular dynamics simulation of nanocrystalline alluminium reveals some surprising behaviour.......How does plastic deformation of polycrystalline materials with grain sizes less than 100 nm look at the atomic scale? A large-scale molecular dynamics simulation of nanocrystalline alluminium reveals some surprising behaviour....

  14. Sorting Techniques for Plastics Recycling

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    This paper presents the basic principles of three different types of separating methods and a general guideline for choosing the most effective method for sorting plastic mixtures. It also presents the results of the tests carried out for separation of PVC, ABS and PET from different kinds of plastic mixtures in order to improve the grade of the raw input used in mechanical or feedstock recycling.

  15. [Modern neuroimaging of brain plasticity].

    Science.gov (United States)

    Kasprian, G; Seidel, S

    2010-02-01

    Modern neuroimaging methods offer new insights into the plasticity of the human brain. As the techniques of functional MRI and diffusion tensor imaging are increasingly being applied in a clinical setting, the examiner is now frequently confronted with the interpretation of imaging findings related to regenerative processes in response to lesions of the central and also of the peripheral nervous system. In this article individual results of modern neuroimaging studies are discussed in the context of structural and functional plasticity of the CNS.

  16. Plastic bronchitis: a management challenge.

    Science.gov (United States)

    Eberlein, Michael H; Drummond, Michael B; Haponik, Edward F

    2008-02-01

    Plastic bronchitis is an uncommon and underdiagnosed entity, characterized by recurrent expectoration of large, branching bronchial casts. We describe a 39-year-woman with no prior lung disease who had episodic wheezing, severe dyspnea with expectoration of large and thick secretions, branching in appearance, which she described as resembling squid. A comprehensive evaluation revealed no specific cause and a diagnosis of idiopathic plastic bronchitis was made. In plastic bronchitis the bronchial casts may vary in size from small segmental casts of a bronchus to casts filling the airways of an entire lung. Plastic bronchitis can therefore present as an acute life-threatening emergency if mechanical obstruction of major airways occurs. The casts are differentiated into type I, inflammatory casts, or type II, acellular casts. The type I inflammatory casts are often associated with bronchial disease and often have an acute presentation. The acellular type of cast production is often chronic or recurrent. Numerous systemic illnesses are associated with plastic bronchitis, but often, as in our patient, no underlying cause can be identified. The treatment of plastic bronchitis includes acute therapy to aid the removal and expectoration of casts, and specific short- or long-term treatments attempting to address the underlying hypersecretory process. The therapeutic options are supported only by anecdotal evidence based on case reports as the rarity and heterogeneity of plastic bronchitis confounds systematic investigations of its treatment. Improved understanding of the regulation of mucus production may allow for new treatment options in plastic bronchitis and other chronic lung diseases characterized by hypersecretion of mucus.

  17. Performance and Emission Studies of a SI Engine using Distilled Plastic Pyrolysis Oil-Petrol Blends

    Directory of Open Access Journals (Sweden)

    Kumar Kareddula Vijaya

    2016-01-01

    Full Text Available In the present work, an experimental investigation is carried out to evaluate the use of plastic oil derived from waste plastic which used in a Spark Ignition engine. Experiments are conducted, the measured performance and emissions of plastic oil blends at different proportions are compared with the baseline operation of the SI engine running with gasoline fuel. Engine performance and exhaust gas emissions such as carbon monoxide, total unburned hydrocarbons, carbon dioxide and oxides of nitrogen are measured. From the experiments it is observed that 50% Distilled Plastic Pyrolysis Oil (50%DPPO exhibits the substantial enhancement in brake power, brake thermal efficiency and reduction in brake specific fuel consumption running at full load conditions among different blends and pure petrol. There is also noticed decrement of carbon dioxide and unburned hydrocarbons emissions at the same blend. The experimental result shows that plastic oil shall conveniently be used as a substitute to gasoline in the existing SI engines without any modifications.

  18. A simple technique for gamma ray and cosmic ray spectroscopy using plastic scintillator

    CERN Document Server

    Nandan, Akhilesh P; Neog, Himangshu; Bhuyan, M R; Biswas, S; Mahapatra, S; Mohanty, B; Mohanty, Rudranarayan; Rout, Subasha; Sahu, P K; Sahu, S; Sakthivel, V A; Samal, P K

    2014-01-01

    A new and simple technique has been developed using plastic scintillator detectors for gamma ray and cosmic ray spectroscopy without single channel analyzer (SCA) or multichannel analyzer (MCA). In these experiments only a leading edge discriminator (LED) and NIM scalers have been used. Energy calibration of gamma spectra in plastic scintillators has been done using Co60 and Cs137 sources. The details experimental technique, analysis procedure and experimental results has been presented in this article.

  19. Transformation plasticity in titanium alpha double prime martensite

    Energy Technology Data Exchange (ETDEWEB)

    Ivasishin, O.M.; Teliovich, R.V. [Institute of Metal Physics, Kiev (Ukraine)

    2001-09-01

    In this paper, explanation of an exceptionally low yield strength and high plasticity of {alpha}{sup ''}-martensite is given using the experimental data on martensite crystal structure of Ti-7%Mo (wt). It is supposed that as-quenched martensite microstructure is a highly nonuniform set of distorted due to compositional modulation microvolumes. Interaction between internal stresses generated in martensite modulated microstructure and external applied stresses modifies crystal lattice in a specific way, leading to a transformation induced plasticity. (orig.)

  20. Error correction and fast detectors implemented by ultrafast neuronal plasticity.

    Science.gov (United States)

    Vardi, Roni; Marmari, Hagar; Kanter, Ido

    2014-04-01

    We experimentally show that the neuron functions as a precise time integrator, where the accumulated changes in neuronal response latencies, under complex and random stimulation patterns, are solely a function of a global quantity, the average time lag between stimulations. In contrast, momentary leaps in the neuronal response latency follow trends of consecutive stimulations, indicating ultrafast neuronal plasticity. On a circuit level, this ultrafast neuronal plasticity phenomenon implements error-correction mechanisms and fast detectors for misplaced stimulations. Additionally, at moderate (high) stimulation rates this phenomenon destabilizes (stabilizes) a periodic neuronal activity disrupted by misplaced stimulations.

  1. Research on Radiation Characteristics of Polymeric Plastic Fiber

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The anti-radiation mechanism of polymeric plastic fiber is analyzed. The radiation characteristic of this type fiber is studied. Our experimental results indicate that under the low radiation dosage (below 1 kGy) the plastic optical fiber's transmission rate rises instead of descends while this type of fiber is radiated by γ ray, electron beam and proton beam respectively. After a period of time, it gradually reaches a constant value. But under the high radiation dosage (above 1 kGy) the fiber's transmission rate descends after radiation. Later, it gradually goes up to a constant value.

  2. ARE PLASTIC GROCERY BAGS SACKING THE ENVIRONMENT?

    OpenAIRE

    Mangal Gogte

    2009-01-01

    This paper is oriented on analysis impacts of plastic bags on environment. In this paper is analyzed did plastic bags are so harmful, and what are the main ingredients of it. One part of this paper is oriented on effects of plastic bags and management of their usage. There is also made comparative analysis between impacts of plastic and paper bags on environment.

  3. Experiments with elasto-plastic oscillator

    DEFF Research Database (Denmark)

    Randrup-thomsen, Søren; Ditlevsen, Ove Dalager

    1996-01-01

    Plastic displacements of a Gaussian white noise excited three degrees of freedom non-ideal elasto-plastic oscillator are measured in laboratory experiments and the plastic displacements are compared to computer simulated results for the corresponding ideal elasto-plastic oscillator. The comparative...

  4. Experiments with elasto-plastic oscillator

    DEFF Research Database (Denmark)

    Randrup-Thomsen, S.; Ditlevsen, Ove Dalager

    1999-01-01

    Plastic displacements of a Gaussian white noise excited three degrees of freedom non-ideal elasto-plastic oscillator are measured in laboratory experiments and the plastic displacements are compared to computer simulated results for the corresponding ideal elasto-plastic oscillator. The comparative...

  5. 49 CFR 192.281 - Plastic pipe.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Plastic pipe. 192.281 Section 192.281... Plastic pipe. (a) General. A plastic pipe joint that is joined by solvent cement, adhesive, or heat fusion may not be disturbed until it has properly set. Plastic pipe may not be joined by a threaded joint...

  6. 49 CFR 192.59 - Plastic pipe.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Plastic pipe. 192.59 Section 192.59 Transportation... BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Materials § 192.59 Plastic pipe. (a) New plastic pipe... specification; and (2) It is resistant to chemicals with which contact may be anticipated. (b) Used plastic...

  7. The Story of the Plastics Industry.

    Science.gov (United States)

    Masson, Don, Ed.

    This is an illustrated informative booklet, designed to serve members of the Society of the Plastics Industry, Inc., and the plastics industry as a whole. It provides basic information about the industry's history and growth, plastics raw materials, typical uses of plastics, properties, and methods of processing and fabricating. (Author/DS)

  8. 110例视网膜色素变性患者RP1基因突变的检测分析%Mutations analysis of RP1 gene in 110 Chinese with retinitis pigmentosa

    Institute of Scientific and Technical Information of China (English)

    闫光辉; 盛迅伦; 李自立; 容维宁; 李慧平; 刘雅妮; 马润清; 马莉

    2011-01-01

    背景 视网膜色素变性(RP)是一组常见的单基因遗传性、致盲性眼底病变,目前尚无有效的治疗方法.目的 研究RP1基因在宁夏地区RP患者中的突变频率及特征,进一步探讨其在RP发病机制中的潜在作用.方法 收集宁夏回族自治区110例RP患者,其中包含35例常染色体显性遗传性RP(ADRP)患者和75例散发患者为RP患者组,同时收集100例健康成年人为正常对照组,2组均采集外周静脉血3~5 ml,应用聚合酶链反应(PCR)和直接测序法进行RP1基因全编码区及邻近剪切位点内含子区域序列突变的检测.运用多因素Logistic回归方法和基于网络的评分软件PolyPhen、Sorting Intolerant from Tolerant(SIFT)对研究结果进行分析.结果 RP患者组和正常对照组RP1基因共检测出11个变异位点,p.Lys1152Lys和c.* 247A>C为新发现的突变.RP患者组第3内含子c.788-92T>C的突变频率与正常对照组比较差异有统计学意义(x2=9.12,P<0.01);3'-侧翼序列区c.*247A>C的突变频率高于正常对照组,差异有统计学意义(x2=12.77,P<0.01),且与RP发生呈显著正相关(r=1.11,P<0.05),其余位点突变均证实为RP1基因的多态性.RP患者组p.Gln1725Gln的突变率显著高于正常对照组(x2=42.09,P<0.01),但其与RP的发生无关(r=1.74,P>0.05).1例散发患者发现了p.Lys1152Lys的突变.在83例RP患者中发现有p-Arg872 His、p.Ala1670Thr和P.Ser1691 Pro突变的同时出现,PolyPhen分析显示,三者均为保护性突变,评分分别为1.11、0.74、0.22;SIFT分析显示,这3个突变均对RP表现为保护作用,评分分别为0.07、0.60、0.22;携带这3个突变的RP患者夜盲出现的平均年龄为30.54岁,27例未携带这3个突变的RP患者夜盲出现的平均年龄为21.06岁;携带这3个突变的RP患者平均最佳矫正视力为0.50±0.38,未携带者的为0.40±0.33,差异有统计学意义(t=2.11,P<0.05).结论在宁夏回族自治区RP患者中,RP1基

  9. Deformation mechanisms of plasticized starch materials.

    Science.gov (United States)

    Mikus, P-Y; Alix, S; Soulestin, J; Lacrampe, M F; Krawczak, P; Coqueret, X; Dole, P

    2014-12-19

    The aim of this paper is to understand the influence of plasticizer and plasticizer amount on the mechanical and deformation behaviors of plasticized starch. Glycerol, sorbitol and mannitol have been used as plasticizers. After extrusion of the various samples, dynamic mechanical analyses and video-controlled tensile tests have been performed. It was found that the nature of plasticizer, its amount as well as the aging of the material has an impact on the involved deformation mechanism. The variations of volume deformation could be explained by an antiplasticization effect (low plasticizer amount), a phase-separation phenomenon (excess of plasticizer) and/or by the retrogradation of starch.

  10. Evolution of phenotypic plasticity in colonizing species.

    Science.gov (United States)

    Lande, Russell

    2015-05-01

    I elaborate an hypothesis to explain inconsistent empirical findings comparing phenotypic plasticity in colonizing populations or species with plasticity from their native or ancestral range. Quantitative genetic theory on the evolution of plasticity reveals that colonization of a novel environment can cause a transient increase in plasticity: a rapid initial increase in plasticity accelerates evolution of a new optimal phenotype, followed by slow genetic assimilation of the new phenotype and reduction of plasticity. An association of colonization with increased plasticity depends on the difference in the optimal phenotype between ancestral and colonized environments, the difference in mean, variance and predictability of the environment, the cost of plasticity, and the time elapsed since colonization. The relative importance of these parameters depends on whether a phenotypic character develops by one-shot plasticity to a constant adult phenotype or by labile plasticity involving continuous and reversible development throughout adult life. © 2014 John Wiley & Sons Ltd.

  11. Identification and Crystallization of Penicillin-Binding Protein/β-Lactamase Homolog (Rp46 from Ruegeria Pomeroyi

    Directory of Open Access Journals (Sweden)

    Bum Han Ryu

    2016-12-01

    Full Text Available In spite of the enormous biological and clinical significance of penicillin-binding protein (PBP/β-lactamase (βL, few of their many homologs (PBP/βLs homologs have been studied crystallographically, and have known functions. Herein, X-ray crystallographic study of a PBP/βL homolog (Rp46 from Ruegeria pomeroyi is described. Multiple sequence alignments indicate that Rp46 has a conserved serine residue within the S70-X-X-K73 motif (Motif I, acting as the catalytic nucleophile. Moreover, an invariant tyrosine residue (Tyr185 and a Trp365-X-Gly motif (Motif III were also identified. The recombinant Rp46 protein was expressed in Escherichia coli and purified to homogeneity judging from the SDS-PAGE analysis. Rp46 was crystallized using a solution consisting of 20% (w/v PEG 3000, 0.1 M Tris-HCl, pH 7.0, 0.2 M calcium acetate, and the X-ray diffraction data were collected to a resolution of 1.90 Å with an Rmerge of 7.4%. The crystals of Rp46 belong to the space group I422, with unit cell parameters a = b = 141.26 Å, and c = 119.75. The structure determination and biochemical characterization are in progress. (Synopsis: A penicillin-binding protein/β-lactamase homolog (Rp46 from Ruegeria pomeroyi was identified and crystallized in the space group I4, and the diffraction data were collected to a resolution of 1.90 Å.

  12. Molecular and biochemical approaches for characterization of antifungal trait of a potent biocontrol agent Bacillus subtilis RP24.

    Science.gov (United States)

    Grover, Minakshi; Nain, Lata; Singh, Shashi Bala; Saxena, Anil Kumar

    2010-02-01

    Bacillus subtilis strain RP24, isolated from rhizoplane of field grown pigeon pea, exhibited in vitro antagonism against a wide range of phytopathogenic fungi. An attempt was made to partially purify and characterize the diffusible antifungal metabolite/s produced by the strain RP24 and its negative mutant (NM) in potato dextrose medium. High performance liquid chromatography (HPLC) of partially purified extract of RP24 showed the presence of lipopeptide antibiotic iturin as a major peak that was comparable to that of standard iturin A (5.230 min) from Sigma-Aldrich whereas the corresponding peak was absent in extract of NM. The structure was further confirmed by liquid chromatographic mass spectrometric (LCMS) analysis as iturin A. LCMS analysis also showed the presence of surfactin and fengycin besides iturin A. Amplification of the lpa-14 (encodes the 4'-phosphopantetheinyl transferase required for the maturation of template enzyme of iturin A) and ituD (encodes a putative malonyl coenzyme A transacylase, whose disruption results in a specific deficiency in iturin A production) genes of iturin operon of strain RP24 was carried out and the sequences obtained were compared with the existing database of NCBI. The sequences of lpa-14 and ituD gene of RP24 showed 98% and 97% homology with lpa-14 and ituD genes of B. subtilis in the existing database. The results indicated that strain RP24 harbors iturin operon in its genome and a chemical mutation in this operon might have resulted in loss of antifungal activity in the negative mutant.

  13. RP-HPLC法测定格列吡嗪缓释片的释放度%RP-HPLC determination of drug release of glipizide sustained release tablets

    Institute of Scientific and Technical Information of China (English)

    屠思远; 蒋海松; 朱德志; 王建明

    2012-01-01

    建立了高效液相色谱法测定格列吡嗪缓释片的释放度.采用反相高效液相色谱法.固定相为ODS C18色谱柱(5μm,4.6 mm×250 mm)以0.1 mol/L磷酸二氢钠溶液(用2 mol/L氢氧化钠溶液调节pH值至(6.00±0.05)-甲醇(55:45)为流动相,流速为1.0 mL/min.柱温室温.检测波长为225nm.采用溶出度测定法第三法装置,以0.5%十二烷基硫酸钠溶液250 mL作为释放介质,转速为50r/min,依法操作,经2、6、10 h取样测定.当格列吡嗪在释放介质中在1.019 ~ 26.49μg/mL质量浓度范围内,峰面积与质量浓度呈良好的线性关系(r =0.999 9).证明方法结果准确,不受制剂中辅料的干扰,适用于格列吡嗪缓释片的释放度测定.%This paper established an RP - HPLC method for the determination of the drug release of glipizide sustained release tablets. The RP - HPLC was on a ODS C18 column (5 μm, 4. 6 mm × 250 mm) at room temperature, using the mobile phase of methanol - buffer solution(0. 1 mol/L sodium dihydrogen phosphate, adjusted to pH (6. 00 ±0. 05) with 2 mol/L sodium hydroxide) (55∶45) , at a flow rate of 1. 0 mL/min and the detection wavelength of 225 nm. Glipizide was detected by the apparatus Ⅲ of dissolution, using as the medium 250 mL of 0. 5% lauryl sodium sulfate solution, at 50 r/min. 5 mL sample of the medium in turn at 2, 6 and 10 h to determine following the above method. The calibration curve was linear in the range of 1. 019 ~ 26. 49 μg/mL. The method was accurate for the drug release determination of glipizide sustained release tablets. The analysis was out of interference of excipients.

  14. RP-HPLC法测定微乳中水飞蓟素的含量%Determination of silymarin in microemulsion by RP-HPLC

    Institute of Scientific and Technical Information of China (English)

    李馨儒; 李艳芳; 周艳霞; 李晓燕; 刘艳

    2009-01-01

    We established a RP-HPLC method for the analysis of silymarin in microemulsion. Silymarin was separated using a ODS Cis column and monitored at the wavelength 288 nm. The mobile phase consisting of methanol-water-acetic acid (42:58:0.5, v/v/v) was pumped at a flow rate of 1.0 mL/min. The linear range of calibration curve was 10-1000 μg/mL. The average recovery was 99.0%-100.7% for silybin isomers. The RSD values of inter-day and intra-day assays were lower than 1.6% for silybin isomers. The method is simple, rapid, reproducible and precise for the quantitative determination of silymarin in microemulsion.%建立测定微乳中水飞蓟素含量的反相高效液相色谱法.采用ODS C18色谱柱,检测波长为288 nm,流动相为甲醇-水-冰醋酸(42:58:0.5,v/v/v),流速为1 mL/min.水飞蓟宾标准曲线的线性范围为10-1000μg/mL,平均回收率为99.0%-100.7%,日内和日间精密度均低于1.6%.该法简单、快速、精确、准确,可用于水飞蓟素微乳制剂质量控制要求.

  15. RP-HPLC测定血浆中间硝苯地平的浓度%Determination of M-nifedipine in Beagle Dogs by RP-HPLC

    Institute of Scientific and Technical Information of China (English)

    杨志福; 周四元; 杨铁宏; 梅其炳

    2006-01-01

    目的建立高效液相色谱法测定Beagle犬血浆中间硝苯地平(m-nifedipine,m-Nif)的浓度,并研究其代谢动力学规律.方法采用正交设计优选色谱和提取条件,血浆样品中m-Nif经碱化、萃取后,用反相高效液相色谱法(RP-HPLC)进行分析测定.色谱分析柱为C18柱(250mm×4.6mm,5μm);流动相为甲醇-10mmol·L-1磷酸盐缓冲液pH5(83∶17);流速为1.0ml/min;检测波长为350nm;内标为MN9201(二氢吡啶类).结果线性范围为10~500ng·ml-1,最低检测浓度为10ng·ml-1,低、中、高3种不同浓度的方法回收率分别为110.84%、105.60%、104.23%;提取回收率分别为92.75%、104.46%、105.12%,日内RSD分别为9.70%、3.05%和1.75%;日间RSD分别为14.53%、7.21%和5.44%.结论本方法稳定、简便、准确,可用于Beagle犬血浆中m-Nif的浓度测定及药代动力学研究.

  16. RP -HPLC determination of piperine in Honghua Ruyi capsules%RP-HPLC法测定红花如意胶囊中胡椒碱的含量

    Institute of Scientific and Technical Information of China (English)

    叶静; 肖美添; 张学勤

    2011-01-01

    目的:建立一种红花如意胶囊中胡椒碱的RP - HPLC含量测定方法.方法:采用Kromasil C18(150 nn ×4.6 mm,5 μm)色谱柱,以甲醇-水(64∶36)为流动相,流速1.0 mL·min-1,检测波长343 nm,柱温30℃;结果:胡椒碱在0.0416~0.228μg范围内呈良好的线性关系(r=0.9998);平均回收率(n=6)为98.82%,RSD为1.1%.结论:所建立的方法便捷、准确,重复性好,可以为藏药红花如意胶囊的质量控制提供一定的参考.%Objective:To establish an HPLC method for the determination of piperine in Honghua Ruyi capsules. Methods:The content of piperine was determined by Kromasil C18( 150 mm ×4. 6 mm,5 μm)column;The mobile phase consisted of methanol - water(64:36)at the flow rate of 1. 0 mL · min-1 ;The detection wavelength was 343 nm, and the temperature of column was 30 ℃. Results: The calibration curve of piperine was linear in the range of 0. 0416 -0. 228 μg(r =0. 9998) ;The average recovery(n =6)of piperine was 98. 82% with RSD of 1. 1%. Conclusion: The method is simple and accurate with good reproducibility. It can be used for quality control of piperine in Honghua Ruyi capsules.

  17. β-decay half-life of the rp-process waiting-point nuclide Mo84

    Science.gov (United States)

    Stoker, J. B.; Mantica, P. F.; Bazin, D.; Becerril, A.; Berryman, J. S.; Crawford, H. L.; Estrade, A.; Guess, C. J.; Hitt, G. W.; Lorusso, G.; Matos, M.; Minamisono, K.; Montes, F.; Pereira, J.; Perdikakis, G.; Schatz, H.; Smith, K.; Zegers, R. G. T.

    2009-01-01

    A half-life of 2.2 ± 0.2 s has been deduced for the ground-state β decay of Mo84, more than 1σ shorter than the previously adopted value. Mo84 is an even-even N=Z nucleus lying on the proton dripline, created during explosive hydrogen burning in type I x-ray bursts in the rapid proton capture (rp) process. The effect of the measured half-life on rp-process reaction flow is explored. Implications on theoretical treatments of nuclear deformation in Mo84 are also discussed.

  18. AgRP Neurons Can Increase Food Intake during Conditions of Appetite Suppression and Inhibit Anorexigenic Parabrachial Neurons.

    Science.gov (United States)

    Essner, Rachel A; Smith, Alison G; Jamnik, Adam A; Ryba, Anna R; Trutner, Zoe D; Carter, Matthew E

    2017-09-06

    To maintain energy homeostasis, orexigenic (appetite-inducing) and anorexigenic (appetite suppressing) brain systems functionally interact to regulate food intake. Within the hypothalamus, neurons that express agouti-related protein (AgRP) sense orexigenic factors and orchestrate an increase in food-seeking behavior. In contrast, calcitonin gene-related peptide (CGRP)-expressing neurons in the parabrachial nucleus (PBN) suppress feeding. PBN CGRP neurons become active in response to anorexigenic hormones released following a meal, including amylin, secreted by the pancreas, and cholecystokinin (CCK), secreted by the small intestine. Additionally, exogenous compounds, such as lithium chloride (LiCl), a salt that creates gastric discomfort, and lipopolysaccharide (LPS), a bacterial cell wall component that induces inflammation, exert appetite-suppressing effects and activate PBN CGRP neurons. The effects of increasing the homeostatic drive to eat on feeding behavior during appetite suppressing conditions are unknown. Here, we show in mice that food deprivation or optogenetic activation of AgRP neurons induces feeding to overcome the appetite suppressing effects of amylin, CCK, and LiCl, but not LPS. AgRP neuron photostimulation can also increase feeding during chemogenetic-mediated stimulation of PBN CGRP neurons. AgRP neuron stimulation reduces Fos expression in PBN CGRP neurons across all conditions. Finally, stimulation of projections from AgRP neurons to the PBN increases feeding following administration of amylin, CCK, and LiCl, but not LPS. These results demonstrate that AgRP neurons are sufficient to increase feeding during noninflammatory-based appetite suppression and to decrease activity in anorexigenic PBN CGRP neurons, thereby increasing food intake during homeostatic need.SIGNIFICANCE STATEMENT The motivation to eat depends on the relative balance of activity in distinct brain regions that induce or suppress appetite. An abnormal amount of activity in

  19. Theory of Lattice Strain for Materials Undergoing Plastic Deformation

    Science.gov (United States)

    Karato, S.

    2008-12-01

    Radial x-ray diffraction is used to probe physical properties of materials including elastic and plastic properties. The theory used behind such an practice is the one developed by Singh (1993) in which the relation between lattice strain and elastic constants and macroscopic stress is derived. In this theory, the variation of inferred stress with the crystallographic planes, (hkl), is due to the elastic anisotropy. However, recent experimental studies showed that in many cases, the variation of stress with (hkl) far exceeds the value expected from this theory. I have developed a modified theory to rectify this problem with Singh's theory. In Singh's theory, the stress distribution in a polycrystalline material is treated only either unrelaxed or relaxed state. The role of plastic deformation is included only to the extent that plastic flow influences this stress state. Such an assumption corresponds to a Voigt model behavior, which is not an appropriate model at high temperatures where continuing plastic flow occurs with concurrent microscopic equilibrium, elastic deformation. This is a Maxwell model type behavior, and my model provides a stress analysis in a Maxwell material with anisotropic and non-linear power-law rheology. In this theory, the lattice strain corresponding to an imposed macroscopic strain-rate is calculated by three steps: (i) conversion of macroscopic strain-rate to macroscopic stress, (ii) conversion of macroscopic stress to microscopic stress at individual grains, and (iii) calculation of microscopic strain due to microscopic stress. The first step involves anisotropy in macroscopic viscosity that depends on anisotropy in crystal plasticity and lattice-preferred orientation. The second step involves anisotropic crystal plasticity and finally the third step involves elastic crystal anisotropy. In most cases, the influence of LPO is weak and in such a case, the lattice strain depends on (hkl) due to the anisotropy in both elastic and plastic

  20. The role of developmental plasticity and epigenetics in human health.

    Science.gov (United States)

    Gluckman, Peter D; Hanson, Mark A; Low, Felicia M

    2011-03-01

    Considerable epidemiological, experimental and clinical data have amassed showing that the risk of developing disease in later life is dependent on early life conditions, mainly operating within the normative range of developmental exposures. This relationship reflects plastic responses made by the developing organism as an evolved strategy to cope with immediate or predicted circumstances, to maximize fitness in the context of the range of environments potentially faced. There is now increasing evidence, both in animals and humans, that such developmental plasticity is mediated in part by epigenetic mechanisms. However, recognition of the importance of developmental plasticity as an important factor in influencing later life health-particularly within the medical and public health communities-is low, and we argue that this indifference cannot be sustained in light of the growing understanding of developmental processes and the rapid rise in the prevalence of obesity and metabolic disease globally. Copyright © 2011 Wiley-Liss, Inc.

  1. Performance of Light-Weight Concrete with Plastic Aggregate

    Directory of Open Access Journals (Sweden)

    Anju Ramesan

    2015-08-01

    Full Text Available This study is intended to explore the suitability of recycled plastics (high density polyethylene as coarse aggregate in concrete by conducting various tests like workability by slump test, compressive strength of cube and cylinder, splitting tensile strength test of cylinder, flexural strength of R.C.C as well as P.CC. beams to determine the properties and behaviour in concrete. Effect of replacement of coarse aggregate with various percentages (0% to 40% of plastic aggregate on behaviour of concrete was experimentally investigated and the optimum replacement of coarse aggregate was found out. The results showed that the addition of plastic aggregate to the concrete mixture improved the properties of the resultant mix.

  2. Estimating the plastic strain with the use of acoustic anisotropy

    Science.gov (United States)

    Belyaev, A. K.; Lobachev, A. M.; Modestov, V. S.; Pivkov, A. V.; Polyanskii, V. A.; Semenov, A. S.; Tret'yakov, D. A.; Shtukin, L. V.

    2016-09-01

    Experimental verification is used to show that reference specimens and structure unloading do not permit obtaining an adequate estimate of plastic strain by measuring the acoustic anisotropy. Analytic estimates of the speed of propagation of a plane acoustic wave of various polarizations in an elastoplastic material in the direction orthogonal to the action of preliminary uniaxial stress are obtained. An analysis of the obtained relations reveala an advantage of using absolute values of the velocity of longitudinal and transverse waves for the plastic strain identification. In contrast to acoustic anisotropy, the velocities vary monotonically in a wider range of plastic strains. At the same time, the elastic strain does not affect the longitude wave velocity, which allows one to use the measurement results to estimate the character of strains.

  3. [Carbon fiber-reinforced plastics as implant materials].

    Science.gov (United States)

    Bader, R; Steinhauser, E; Rechl, H; Siebels, W; Mittelmeier, W; Gradinger, R

    2003-01-01

    Carbon fiber-reinforced plastics have been used clinically as an implant material for different applications for over 20 years.A review of technical basics of the composite materials (carbon fibers and matrix systems), fields of application,advantages (e.g., postoperative visualization without distortion in computed and magnetic resonance tomography), and disadvantages with use as an implant material is given. The question of the biocompatibility of carbon fiber-reinforced plastics is discussed on the basis of experimental and clinical studies. Selected implant systems made of carbon composite materials for treatments in orthopedic surgery such as joint replacement, tumor surgery, and spinal operations are presented and assessed. Present applications for carbon fiber reinforced plastics are seen in the field of spinal surgery, both as cages for interbody fusion and vertebral body replacement.

  4. (S,R,Rp-N,N-Dimethyl-1-{2-[(1-phenylethylaminomethyl]ferrocenyl}ethanamine

    Directory of Open Access Journals (Sweden)

    Xiu-Li Zheng

    2009-04-01

    Full Text Available The title chiral ferrocene compound, [Fe(C5H5(C18H25N2], contains one planar and two central chiral centers. It is of interest with respect to asymmetric catalysis. The absolute configuration of the planar chirality is Rp at the ferrocene group and those of the two C chiral centers are R at the CH carbon of the ethanamine unit and S at the CH carbon of the phenylethylamino substituent. In the ferrocenyl unit, the cyclopentadienyl (Cp rings are planar, with maximum deviations of 0.002 (2 Å for the substituted and 0.008 (3 Å for the unsubstituted Cp ring. The dihedral angle between the ring planes is 2.12 (15° and the rings are twisted slightly from an eclipsed conformation by 7.06–7.60°.

  5. Heterogeneity of caprine beta-casein elucidated by RP-HPLC/MS: genetic variants and phosphorylations.

    Science.gov (United States)

    Neveu, Carole; Mollé, Daniel; Moreno, Javier; Martin, Patrice; Léonil, Joëlle

    2002-11-01

    Casein variants occurring in milks from goats homozygous at the alpha(s1)-Cn locus were separated and identified by an RP-HPLC/ESI-MS method. Preferential haplotypes arose as well as some particularities in posttranslational modifications. A new variant of caprine beta-Cn, named C, as well as the phosphorylations pattern of the protein were characterized by the combined use of peptide mass fingerprinting and sequencing by tandem mass spectrometry. The molecular mass of the new variant in its 6P form was measured as 23854 Da and it differs in a mono amino acid substitution, A177 --> V177, from the variant A. The phosphorylation pattern of caprine beta-Cn is homologous to bovine beta-Cn concerning the 5P located on Ser15, 17, 18, 19, 35 but it presents a specific additional phosphorylation site on Thr12 that is comparable to human beta-Cn phosphorylation located on Thr3.

  6. Stability Indicating RP-HPLC Method for Determination of Valsartan in Pure and Pharmaceutical Formulation

    Directory of Open Access Journals (Sweden)

    S. K. Patro

    2010-01-01

    Full Text Available A simple, rapid and accurate and stability indicating RP-HPLC method was developed for the determination of valsartan in pure and tablet forms. The method showed a linear response for concentrations in the range of 50-175 µg/mL using 0.01 M NH4H2PO4 (pH 3.5 buffer: methanol [50:50] as the mobile phase with detection at 210 nm and a flow rate of 1 mL/min and retention time 11.041 min. The method was statistically validated for accuracy, precision, linearity, ruggedness, robustness, forced degradation, solution stability and selectivity. Quantitative and recovery studies of the dosage form were also carried out and analyzed; the % RSD from recovery studies was found to be less than 1. Due to simplicity, rapidity and accuracy of the method, we believe that the method will be useful for routine quality control analysis.

  7. DETERMINATION OF PROTEINS FROM BUFFALO MILK USING HIGH PERFORMANCE LIQUID CROMATOGRAPHY RP-HPLC

    Directory of Open Access Journals (Sweden)

    AURELIA PECE

    2013-12-01

    Full Text Available In the hereby paper, we have undertaken a study on buffalo milk proteins, employing high performance liquid chromatography (HPLC. This RP-HPLC technique is commonly employed in the separation and assessment of caseins K, and in the fresh, as well as processed milk. These methods are also successfully applied in the authenticity and origin assessment of certain cheese products and the qualitative analysis of milk in bubalines, ovines, caprines and bovines (Ferreira si Cacote, 2003; Veloso si colab., 2002. In order to identify the main protein types, we found support in literature data (Miranda si colab., 2004, and thus achieved the chromatographic separation on whole milk, lactoserum and casein samples.

  8. SIMULTANEOUS ESTIMATION OF SAXAGLIPTIN HYDROCHLORIDE AND METFORMIN HYDROCHLORIDE IN ACTIVE PHARMACEUTICAL INGRIDENT BY RP-HPLC

    Directory of Open Access Journals (Sweden)

    NYOLA NARENDRA, GOVINDASAMY JEYABALAN

    2013-09-01

    Full Text Available A new simple, accurate, precise and reproducible RP-HPLC method has been developed for the simultaneousestimation of Saxagliptin and Metformin in bulk drug form using C18 column (Phenomenex, 250 x 4.6 mm, 5 μm inisocratic mode. The mobile phase consisted of 0.02M Potassium dihydrogen phosphate (KH2PO4, Acetonitrile,Methanol in the ratio of 50:25:25 (v/v/v at pH 4.3. The detection wavelength was carried out at 240 nm. Themethod was linear over the concentration range for Saxagliptin 10-50μg/ml and for Metformin 5-25 μg/ml. Therecoveries of Saxagliptin and Metformin were found to be 100.48and 101.1% respectively. The validation of methodwas carried out utilizing ICH-guidelines. The described HPLC method was successfully employed for the analysisof pharmaceutical formulations containing combined dosage form.

  9. RP-HPLC analysis of Jirakadyarishta and chemical changes during fermentation.

    Science.gov (United States)

    Lal, Uma Ranjan; Tripathi, Shailendra Mani; Jachak, Sanjay M; Bhutani, Kamlesh Kumar; Singh, Inder Pal

    2010-11-01

    Jirakadyarishta, an Ayurvedic formulation prepared by the fermentation of a decoction of Cuminum cyminum (seeds) is traditionally used for intestinal disorders. RP-HPLC analysis of the decoction and the final processed formulation revealed that apigenin-7-O-[galacturonide (1 --> 4)-O-glucoside] and luteolin-4'-O-glucoside-7-O-galacturonide) were the two major constituents of the decoction of C. cyminum. Selective hydrolysis of 7-O-glucosides of luteolin and apigenin during fermentation resulted in an increase in the amount of luteolin and apigenin. The 4'-O-glucoside-7-O-galacturonide of luteolin and galacturonide derivative of apigenin were not hydrolyzed during fermentation. Monomeric phenolics, together with 5-hydroxymethyl furfural (5-HMF), were also introduced into the formulation through the jaggery and other plant materials during fermentation. This communication highlights the importance of the ancient processing methods used in Ayurveda.

  10. Estudio del haz de neutrones del reactor RP-10 aplicados a la neutrografía

    OpenAIRE

    Zegarra,Manuel; López, Alcides

    2014-01-01

    Se estudió el haz de neutrones del conducto radial N° 3 del reactor RP-10 que es usado para la obtención de neutrografías, mediante la comparación de registros neutrográficos con y sin el ducto interno, así como la determinación del flujo neutrónico a 2 grupos mediante hojuelas de In a lo largo del conducto exterior, encontrándose la presencia de fotones que crean señales en niveles comparables a los efectos de los neutrones que disminuyen la calidad del análisis. Se obtuvieron valores de al...

  11. Dynamic Critical Behaviour of Wolff's Algorithm for $RP^N$ $\\sigma$-Models

    CERN Document Server

    Caracciolo, Sergio; Pelissetto, A; Sokal, A D

    1992-01-01

    We study the performance of a Wolff-type embedding algorithm for $RP^N$ $\\sigma$-models. We find that the algorithm in which we update the embedded Ising model \\`a la Swendsen-Wang has critical slowing-down as $z_\\chi \\approx 1$. If instead we update the Ising spins with a perfect algorithm which at every iteration produces a new independent configuration, we obtain $z_\\chi \\approx 0$. This shows that the Ising embedding encodes well the collective modes of the system, and that the behaviour of the first algorithm is connected to the poor performance of the Swendsen-Wang algorithm in dealing with a frustrated Ising model.

  12. HPLC METHOD DEVELOPMENT OF AMLODIPINE BY RP-HPLC IN ITS BULK DOSAGE FORMS

    Directory of Open Access Journals (Sweden)

    V. Naveen Kumar, K. Kiran kumar, P. Ramesh Babu, K. Anilkumar

    2012-06-01

    Full Text Available A new, simple, precise, sensitive, accurate and reproducible Reverse phase HPLC method was developed and validated for the analysis of amlodipine in bulk dosage forms. The separation was conducted by using c-18 RP-HPLC coloumn, which was maintained at ambient temperature. The mobile phase consisting of Phosphate buffer and Acetonitrile (90:10v/v was delivered at a rate of 1.5 ml/min. The analysis was detected by using UV detector at the wave length of 225nm.The method is validated for its specificity, precision, accuracy, linearity and robustness. The method was found to be linear over the concentration range 10-100 g/ml (r2 =0.999. The retention time for amlodipine was found to be 3.34min. Limit of quantification of the method is 0.179g/ml and limit of detection is 0.054 g/ml.

  13. Simultaneous RP-HPLC Estimation of Cefpodoxime Proxetil and Clavulanic Acid in Tablets

    Science.gov (United States)

    Malathi, S.; Dubey, R. N.; Venkatnarayanan, R.

    2009-01-01

    A new, simple, precise, rapid and accurate RP-HPLC method has been developed for the simultaneous estimation of cefpodoxime proxetil and clavulanic acid from pharmaceutical dosage forms. The method was carried out on a Zorbax Eclipse XDB 5 μ C 18 (150×4.6 mm) column with a mobile phase consisting of acetonitrile:50 mM potassium dihydrogen phosphate buffer (pH 3.0, 70:30 v/v) at a flow rate of 1.0 ml/min. Detection was carried out at 228 nm. Aspirin was used as an internal standard. The retention time of clavulanic acid, cefpodoxime proxetil and aspirin was 4.43, 6.44 and 5.6 min, respectively. The developed method was validated in terms of accuracy, precision, linearity, limit of detection, limit of quantification and solution stability. The proposed method can be used for the estimation of these drugs in combined dosage forms. PMID:20177474

  14. Simultaneous RP-HPLC estimation of cefpodoxime proxetil and clavulanic acid in tablets

    Directory of Open Access Journals (Sweden)

    Malathi S

    2009-01-01

    Full Text Available A new, simple, precise, rapid and accurate RP-HPLC method has been developed for the simultaneous estimation of cefpodoxime proxetil and clavulanic acid from pharmaceutical dosage forms. The method was carried out on a Zorbax Eclipse XDB 5 µ C 18 (150x4.6 mm column with a mobile phase consisting of acetonitrile:50 mM potassium dihydrogen phosphate buffer (pH 3.0, 70:30 v/v at a flow rate of 1.0 ml/min. Detection was carried out at 228 nm. Aspirin was used as an internal standard. The retention time of clavulanic acid, cefpodoxime proxetil and aspirin was 4.43, 6.44 and 5.6 min, respectively. The developed method was validated in terms of accuracy, precision, linearity, limit of detection, limit of quantification and solution stability. The proposed method can be used for the estimation of these drugs in combined dosage forms.

  15. A Validated RP-HPLC Method for the Determination of Atazanavir in Pharmaceutical Dosage Form

    Directory of Open Access Journals (Sweden)

    K. Srinivasu

    2011-01-01

    Full Text Available A validated RP HPLC method for the estimation of atazanavir in capsule dosage form on YMC ODS 150 × 4.6 mm, 5 μ column using mobile phase composition of ammonium dihydrogen phosphate buffer (pH 2.5 with acetonitrile (55:45 v/v. Flow rate was maintained at 1.5 mL/min with 288 nm UV detection. The retention time obtained for atazanavir was at 4.7 min. The detector response was linear in the concentration range of 30 - 600 μg/mL. This method has been validated and shown to be specific, sensitive, precise, linear, accurate, rugged, robust and fast. Hence, this method can be applied for routine quality control of atazanavir in capsule dosage forms as well as in bulk drug.

  16. RP-HPLC method for the quantitation of β-Sitosterol in Elaeagnus Gonyanthes Benth

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Objective To establish an RP-HPLC method for the determination of β-Sitosterol in Elaeagnus Gonyanthes Benth.Methods The separation was performed on a luna C8(2)(150 mm×4.6 mm,5μm)column with the mobile phase of methanol-water(88∶12,v/v)at a flow rate of 1.0 mL/min,the detection wavelength was set at 210 nm,and the temperature of the column was maintained at 35 ℃.Results The calibration curve of β-Sitosterol was linear over the concentration range of 0.075-0.375 mg/mL(r=0.9999)and the average recovery of β-...

  17. RP - HPLC Method for Determination of Piperine from Piper longum Linn. and Piper nigrum Linn

    Directory of Open Access Journals (Sweden)

    M. K. Santosh

    2005-01-01

    Full Text Available Piper longum Linn. and Piper nigrum Linn. are used as spices and medicines. Quantitative determination of piperine was undertaken to provide an easy and simple analytical method, which can be used as a routine quality control method. RP-HPLC was performed using methanol and water as mobile phase. The detection and quantification was performed at a wavelength of 345 nm. Linearity of detector response for piperine was between the concentrations 0.005% to 0.1%. The correlation coefficient obtained for the linearity was 0.998. The assay value of piperine for fruit and root of P. longum was found to be 0.879% and 0.31%. The assay value of piperine for fruit of P. nigrum was 4.5%. The recovery value of standard piperine was 99.4%. Low value of standard deviation and coefficient of variation are indicative of high precision of the method.

  18. Dynamics of higher-dimensional FRW cosmology in $R^p$ exp($\\lambda R$) gravity

    Indian Academy of Sciences (India)

    SEBIKA KANGSHA BANIK; KALYAN BHUYAN

    2017-02-01

    We study the cosmological dynamics for $R_p$ exp($\\lambda R$) gravity theory in the metric formalism, using dynamical systems approach. Considering higher-dimensional FRW geometries in case of an imperfect fluid which has two different scale factors in the normal and extra dimensions, we find the exact solutions, and study its behaviour and stability for both vacuum and matter cases. It is found that stable solutions corresponding to accelerated expansion at late times exist, which can describe the inflationary era of the Universe. We also study the evolution of scale factors both in the normal and extra dimensions for different values of anisotropy parameter and the number of extra dimensions for such a scenario.

  19. Neutron flux optimization in irradiation facilities at Peruvian research reactor RP-10

    Energy Technology Data Exchange (ETDEWEB)

    Vela, M.; Arrieta, R.; Salazar, A.; Urcia, A.; Canaza, D.; Felix, J; Veramendi, E.; Ovalle, E.; Giol, R.; Zapata, L.; Ramos, F.; Tordocillo, J. [Instituto Peruano de Energia Nuclear (IPEN), Lima (Peru). Direccion de Instalaciones. Dept. de Reactores]. E-mail: mvela@ipen.gob.pe; rarrieta@ipen.gob.pe

    2005-07-01

    In this work we show the values distribution of the neutron flux at Peruvian Research Reactor RP-10, determined under two different safety and control rods configurations. The method applied was to irradiate small gold foils in irradiation facilities of the core to carry out the nuclear reaction {sup 197}Au(n, {gamma}){sup 198}Au; then using a gamma spectrometry system and the Westcott formalism we obtained the neutron flux. The results confirm the favorable effect of such configurations, increasing the neutron flux, both thermal and epithermal. These results have consistency with the weekly activity reports of radioisotopes lots given by the Radioisotopes Production Plant and Neutron Activation Analysis Group. (author)

  20. Determination of Withaferin-A in two Withania Species by RP-HPLC method

    Directory of Open Access Journals (Sweden)

    Dalavayi Shaila

    2006-01-01

    Full Text Available Withania is a small shrub possessing medicinal value commonly found in the Indian subcontinent. Quantitative determination of withaferin-A, was undertaken to provide an easy and simple analytical method, which can be used as a routine quality control method. RP-HPLC was performed using acetonitrile and water as mobile phase. The detection and quantification was performed at a wavelength of 225 nm. Linearity of detector response for withaferin-A was between the concentrations 0.005% to 0.02%. The correlation coefficient obtained for the linearity was 0.993. The recovery value of standard withaferin-A was 94.4%. Low value of standard deviation and coefficient of variation, are indicative of high precision of the method. The system was successfully used to investigate the marker compound in different plant parts of W. coagulans and W. somnifera.