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Sample records for mm ho ca

  1. Cryogenic Ho:CaF2 laser pumped by Tm:fiber laser

    NASA Astrophysics Data System (ADS)

    Jelínek, Michal; Kubeček, Václav; Ma, Weiwei; Zhao, Beibei; Jiang, Dapeng; Su, Liangbi

    2016-06-01

    The laser operation in the pulsed as well as continuous-wave regime of a modified-Bridgeman-grown 0.5 at.% Ho:CaF2 crystal at 83 K pumped by a Tm:fiber laser is reported. The maximum output power was 2.37 W at 2060 nm or 1.3 W at 2110 and 2130 nm. Continuous tuning range over 90 nm from 2030 to 2120 nm was achieved using a birefringent filter. The Ho:CaF2 fundamental spectroscopic properties as absorption and fluorescence spectra at 83 and 293 K are also presented.

  2. Visualiser of two-micron laser radiation based on Ho:CaF{sub 2} crystals

    SciTech Connect

    Lyapin, A A; Ryabochkina, P A; Ushakov, S N; Fedorov, P P

    2014-06-30

    The anti-Stokes luminescence spectra of Ho:CaF{sub 2} crystals corresponding to the {sup 5}G{sub 4} → {sup 5}I{sub 8}, {sup 5}G{sub 5} → {sup 5}I{sub 8}, {sup 5}F{sub 3} → {sup 5}I{sub 8}, {sup 5}F{sub 4}({sup 5}S{sub 2}) → {sup 5}I{sub 8}, {sup 5}F{sub 5} → {sup 5}I{sub 8}, {sup 5}S{sub 2} → {sup 5}I{sub 7}, {sup 5}I{sub 4} → {sup 5}I{sub 8}, {sup 5}I{sub 5} → {sup 5}I{sub 8}, {sup 5}F{sub 5} → {sup 5}I{sub 7}, {sup 5}F{sub 3} → {sup 5}I{sub 6}, {sup 5}I{sub 6} → {sup 5}I{sub 8}, {sup 5}F{sub 5} → {sup 5}I{sub 6}, and {sup 5}I{sub 5} → {sup 5}I{sub 7} transitions upon excitation of the {sup 5}I{sub 7} level of Ho{sup 3+} ions are studied. A method for visualisation of IR radiation in the two-micron range using Ho:CaF{sub 2} crystals is proposed. The energy efficiency of conversion of two-micron laser radiation to radiation in the red spectral range 620 – 690 nm by a 1 mol % HoF{sub 3}:CaF{sub 2} crystal is estimated to be no higher than 0.02%. (nonlinear optical phenomena)

  3. Multicolour upconversion emission from Ho3+-Tm3+-Yb3+ codoped CaMoO4 phosphor

    NASA Astrophysics Data System (ADS)

    Dey, Riya; Rai, Vineet Kumar

    2015-05-01

    The Ho3+-Tm3+-Yb3+ codoped CaMoO4 phosphor powder has been synthesized by chemical coprecipitation technique. For the structural investigation the X-ray diffraction analysis has been done. Multicolour upconversion (UC) emission in the visible region from the prepared material has been observed under the 980 nm near infrared (NIR) excitation. The UC emission bands ˜ 474 nm (blue), ˜ 541 nm (green) and ˜ 661 nm (red) region have been assigned as 1G4→3H6 (Tm3+), 5F45S2→5I8 (Ho3+) and 5F5→5I8 (Ho3+) transitions respectively.

  4. Adapting TESLA technology for future cw light sources using HoBiCaT

    NASA Astrophysics Data System (ADS)

    Kugeler, O.; Neumann, A.; Anders, W.; Knobloch, J.

    2010-07-01

    The HoBiCaT facility has been set up and operated at the Helmholtz-Zentrum-Berlin and BESSY since 2005. Its purpose is testing superconducting cavities in cw mode of operation and it was successfully demonstrated that TESLA pulsed technology can be used for cw mode of operation with only minor changes. Issues that were addressed comprise of elevated dynamic thermal losses in the cavity walls, necessary modifications in the cryogenics and the cavity processing, the optimum choice of operational parameters such as cavity temperature or bandwidth, the characterization of higher order modes in the cavity, and the usability of existing tuners and couplers for cw.

  5. Adapting TESLA technology for future cw light sources using HoBiCaT.

    PubMed

    Kugeler, O; Neumann, A; Anders, W; Knobloch, J

    2010-07-01

    The HoBiCaT facility has been set up and operated at the Helmholtz-Zentrum-Berlin and BESSY since 2005. Its purpose is testing superconducting cavities in cw mode of operation and it was successfully demonstrated that TESLA pulsed technology can be used for cw mode of operation with only minor changes. Issues that were addressed comprise of elevated dynamic thermal losses in the cavity walls, necessary modifications in the cryogenics and the cavity processing, the optimum choice of operational parameters such as cavity temperature or bandwidth, the characterization of higher order modes in the cavity, and the usability of existing tuners and couplers for cw. PMID:20687747

  6. Hydrides of CeNi/sub 5/, MmNi/sub 5/, Ca/sub 0/ /sub 2/(Ce/sub 0/ /sub 65/Mm/sub 0/ /sub 35/)/sub 0/ /sub 8/Ni/sub 5/, Ca/sub 0/ /sub 2/Ce/sub 0/ /sub 8/Ni/sub 5/, Ca/sub 0/ /sub 2/Mm/sub 0/ /sub 8/Ni/sub 5/, and mixed CeNi/sub 5//MmNi/sub 5/

    SciTech Connect

    Lakner, J.F.; Chow, T.S.

    1982-09-01

    Six intermetallic alloys (CeNi/sub 5/, MmNi/sub 5/, Ca/sub 0/ /sub 2/(Ce/sub 0/ /sub 65/Mm/sub 0/ /sub 35/)/sub 0/ /sub 8/Ni/sub 5/, Ca/sub 0/ /sub 2/Ce/sub 0/ /sub 8/Ni/sub 5/, Ca/sub 0/ /sub 2/Mm/sub 0/ /sub 8/Ni/sub 5/, and a mixed alloy, CeNi/sub 5//MmNi/sub 5/) were investigated with respect to their suitability to provide high hydrogen capacity and their potential for use in providing substantial hydrogen pressure at both low and high temperatures. A second phase of our investigation dealt with ball-milling and hydriding and dehydriding cycles to produce fine particles for use in hydride powder transfer studies. A summary of several Van't Hoff plots is also included for hydride-forming alloys.

  7. Contrasting Effects of Ca{sup 2+} and Ho{sup 3+} Substitutions on Superconductivity and Excess conductivity of (Ho{sub 1-x}Ca{sub x})(Ba{sub 2-y}Ho{sub y})Cu{sub 3}O{sub 7-{delta}}

    SciTech Connect

    Maulud, M. F.; Hamidi, Z. S.; Yusof, A. A.; Yusof, M. I. M.; Yahya, A. K.

    2010-07-07

    Effects of Ho{sup 3+} and Ca{sup 2+} substitutions in (Ho{sub 1-x}Ca{sub x})(Ba{sub 2-y}Ho{sub y})Cu{sub 3}O{sub 7-{delta}}ceramics on normal and superconducting state behaviour were investigated. Electrical resistivity measurements showed increasing Ho{sup 3+} substitution at Ba{sup 2+} site (x = 0, 0.4, y = 0-0.4) caused normal state resistivity to change from metal-like to semimetal/semiconductor-like behaviour and suppressed T{sub c} from 89 K (y = 0) to 72 K (y = 0.4) while substitution of Ca{sup 2+} for Ho{sup 3+}((x = 0.2) 0.4, (y 0.4)) revives metallic behaviour of the normal state with increasing x. Excess conductivity analysis based on Asmalazov-Larkin theory showed 2D to 3D transition for all superconducting samples but with contrasting effects of the substitutions on AL{sub 2D} and AL{sub 3D} constants. The resistivity and excess conductivity results indicate effective hole filling Ho{sup 3+} and hole doping by by Ca{sup 2+} substitutions.

  8. The modulated structure and frequency upconversion properties of CaLa2(MoO4)4:Ho(3+)/Yb(3+) phosphors prepared by microwave synthesis.

    PubMed

    Lim, Chang Sung; Aleksandrovsky, Aleksandr; Molokeev, Maxim; Oreshonkov, Aleksandr; Atuchin, Victor

    2015-07-15

    CaLa2-x(MoO4)4:Ho(3+)/Yb(3+) phosphors with the doping concentrations of Ho(3+) and Yb(3+) (x = Ho(3+) + Yb(3+), Ho(3+) = 0.05; Yb(3+) = 0.35, 0.40, 0.45 and 0.50) have been successfully synthesized by the microwave sol-gel method. The modulated and averaged crystal structures of CaLa2-x(MoO4)4:Ho(3+)/Yb(3+) molybdates have been found by the Rietveld method, and the upconversion photoluminescence properties have been investigated. The synthesized particles, being formed after the heat-treatment at 900 °C for 16 h, showed a highly crystallized state. Under the excitation at 980 nm, CaLa2-x(MoO4)4:Ho(3+)/Yb(3+) particles exhibited strong 545 and 655 nm emission bands in the green and red regions. When the Yb(3+) : Ho(3+) ratios are 9 : 1 and 10 : 1, the UC intensity of CaLa1.5(MoO4)4:Yb0.45/Ho0.05 and CaLa1.45(MoO4)4:Yb0.50/Ho0.05 particles is the highest for different bands. The CIE coordinates calculated for CaLa2-x(MoO4)4:Ho(3+)/Yb(3+) phosphors are related to the yellow color field. The Raman spectrum of undoped CaLa2(MoO4)4 has revealed about 13 narrow lines. The strongest band observed at 906 cm(-1) was assigned to the ν1 symmetric stretching vibration of MoO4 tetrahedra. The spectra of the samples doped with Ho and Yb, as obtained under the 514.5 nm excitation, were dominated by Ho(3+) luminescence over the wavenumber range of >700 cm(-1) preventing the recording of the Raman spectra. PMID:26138938

  9. Intense Upconversion Luminescence of CaSc2 O4 :Ho(3+) /Yb(3+) from Large Absorption Cross Section and Energy-Transfer Rate of Yb(3.).

    PubMed

    Li, Jing; Zhang, Jiahua; Hao, Zhendong; Chen, Li; Zhang, Xia; Luo, Yongshi

    2015-05-18

    Concentration-optimized CaSc2 O4 :0.2 % Ho(3+) /10 % Yb(3+) shows stronger upconversion luminescence (UCL) than a typical concentration-optimized upconverting phosphor Y2 O3 :0.2 % Ho(3+) /10 %  b(3+) upon excitation with a 980 nm laser diode pump. The (5) F4 +(5) S2 →(5) I8 green UCL around 545 nm and (5) F5 →(5) I8 red UCL around 660 nm of Ho(3+) are enhanced by factors of 2.6 and 1.6, respectively. On analyzing the emission spectra and decay curves of Yb(3+) : (2) F5/2 →(2) F7/2 and Ho(3+) : (5) I6 →(5) I8 , respectively, in the two hosts, we reveal that Yb(3+) in CaSc2 O4 exhibits a larger absorption cross section at 980 nm and subsequent larger Yb(3+) : (2) F5/2 →Ho(3+) : (5) I6 energy-transfer coefficient (8.55×10(-17) cm(3) s(-1) ) compared to that (4.63×10(-17) cm(3) s(-1) ) in Y2 O3 , indicating that CaSc2 O4 :Ho(3+) /Yb(3+) is an excellent oxide upconverting material for achieving intense UCL. PMID:25721224

  10. Multicolour upconversion emission from Ho{sup 3+}-Tm{sup 3+}-Yb{sup 3+} codoped CaMoO{sub 4} phosphor

    SciTech Connect

    Dey, Riya; Rai, Vineet Kumar

    2015-05-15

    The Ho{sup 3+}-Tm{sup 3+}-Yb{sup 3+} codoped CaMoO4 phosphor powder has been synthesized by chemical coprecipitation technique. For the structural investigation the X-ray diffraction analysis has been done. Multicolour upconversion (UC) emission in the visible region from the prepared material has been observed under the 980 nm near infrared (NIR) excitation. The UC emission bands ∼ 474 nm (blue), ∼ 541 nm (green) and ∼ 661 nm (red) region have been assigned as {sup 1}G{sub 4}→{sup 3}H{sub 6} (Tm{sup 3+}), {sup 5}F{sub 4}{sup 5}S{sub 2}→{sup 5}I{sub 8} (Ho{sup 3+}) and {sup 5}F{sub 5}→{sup 5}I{sub 8} (Ho{sup 3+}) transitions respectively.

  11. Upconversion luminescence properties and color tunability of 12CaOṡ7Al2O3:Ho3+/Yb3+ single crystal

    NASA Astrophysics Data System (ADS)

    Qu, Yunfei; Qiu, Zhaozhong; Wang, Rui; Liu, Liang; Tao, Ye; Zhou, Jianjun

    2016-03-01

    Rear earth (RE) ions-doped 12CaOṡ7Al2O3 single crystal has been successfully prepared by Czochralski method. Under 980 nm excitation, a strong green upconversion emission at 548 nm and a weaker red upconversion emission at 662 nm were observed. The green upconversion emission is corresponding to the transition of 5F 4/5S2 →5I8 of Ho3+, and the red one is corresponding to the transition of 5F5 →5I8 of Ho3+. A much weaker NIR band at 762 nm is also observed, which corresponds to the 5F 4/5S2 →5I7 transition of Ho3+. The pump dependence and luminescence decay dynamics spectra show the green and red upconversion are populated by two-photon process, and the upconversion mechanisms are analyzed in detail. The color of the upconversion luminescence can be changed by simply adjusting the excitation power. RE ions-doped 12CaOṡ7Al2O3 single crystal with these properties is expected to have broad application prospects in solid-state multicolor display and instrument integration. RE ions-doped 12CaOṡ7Al2O3 single crystal has the ability to replace some traditional single crystals such as LiNbO3 in many applications.

  12. Studies on the new superconducting system (RE) Ba2Ca3Sr4Cu5Ox (RE=Gd, Ho & Dy)

    NASA Astrophysics Data System (ADS)

    Arumugam, S.

    1996-03-01

    Superconducting studies have been carried out in the new high TC (50-65K) system (RE)Ba2Ca3Sr4Cu5OX [(RE) 12345] with RE=Gd, Ho&Dy. The unit cell dimensions are of the order of a=5.44 °A, b=5.46°A and c=14.62°A. The data above the diamagnetic onset and below the upturn temperature due to ordering were analyzed to yield the effective magnetic moments (Peff) of the rare earth ions.

  13. Random strain effects in optical and EPR spectra of electron-nuclear excitations in CaWO4:Ho(3+) single crystals.

    PubMed

    Shakurov, G S; Chukalina, E P; Popova, M N; Malkin, B Z; Tkachuk, A M

    2014-12-01

    We study paramagnetic Ho(3+) centers in CaWO4, a promising material for applications in quantum electronics and quantum information devices. Oriented single crystals with nominal holmium concentrations 0.05, 0.5, and 1 at% were investigated at 4.2 K using EPR spectroscopy in the frequency range 37-850 GHz at temperatures 5-40 K and high-resolution optical transmission spectroscopy in the infrared and visible wave-length ranges. Along with the tetragonal Ho(3+) centers of the S4 point symmetry, four different types of low-symmetry centers were identified in the EPR spectra and their spectral parameters were determined. A well resolved hyperfine structure exhibiting holmium concentration dependent features was observed in optical spectra. Modeling of the spectra taking into account random lattice strains gave a possibility of reproducing satisfactorily the measured hyperfine structure of the EPR signals, in particular, at anticrossings of the electron-nuclear sublevels of the ground non-Kramers doublet, and the envelopes of the hyperfine structure of optical transitions. The widths of the probability distribution of random deformations related to the point lattice defects in the samples with different concentrations of the impurity Ho(3+) ions were estimated from a comparison of the simulated spectra with the experimental data. PMID:25315262

  14. Removal of rhodamine 6G dye contaminant by visible light driven immobilized Ca1-xLnxMnO3 (Ln = Sm, Ho; 0.1 ≤ x ≤ 0.4) photocatalysts

    NASA Astrophysics Data System (ADS)

    Barrocas, B.; Sério, S.; Rovisco, A.; Nunes, Y.; Jorge, M. E. Melo

    2016-01-01

    Visible-light-driven Ca1-xLnxMnO3 (Ln = Sm, Ho; 0.1 ≤ x ≤ 0.4) films were grown by RF-magnetron sputtering onto fused silica substrates. The effects of Ca2+ substitution for Ho3+ or Sm3+ in Ca1-xLnxMnO3 on the structural, morphological and photocatalytic properties for rhodamine 6G dye degradation under visible light irradiation were investigated. XRD showed a pure typical perovskite phase for all the prepared films, except for Ca0.9Ho0.1MnO3 and a decrease of the crystallite size with the increase of the amount of ion substituted. SEM and AFM revealed that the films surface is dense, with low roughness. UV-vis spectroscopy indicated for the two series band gaps in the range of 1.6-2.8 eV, being lower for the films containing holmium. The results showed that some Ca1-xHoxMnO3 and Ca1-xSmxMnO3 films present higher photocatalytic activity for Rh6G degradation in comparison with TiO2 films and for the same x value the Ho-films exhibited higher photocatalytic activity. For both films series the maximal degradation rate was obtained for x = 0.2; above this content the degradation percentage exhibits a decreasing trend with the increase of Ho or Sm substitution, except for x = 0.4 in the case of Ho system, which is observed again an increase in the degradation rate. The Rh6G photocatalytic degradation followed a pseudo first-order reaction kinetics. XRD and SEM of the used photocatalysts evidenced high photochemical stability.

  15. The magnetic properties of R in Pb 2Sr 2(R/Ca)Cu 3O 8 (R = HO and Er)

    NASA Astrophysics Data System (ADS)

    Soderholm, L.; Loong, C.-K.; Staub, U.; Skanthakumar, S.; Simon Xue, J.; Hammonds, J. P.; Greedan, J. E.; Maric, M.

    1995-02-01

    The electronic behavior of the rare-earth ion (R) in the Pb based superconductors Pb 2Sr 2(R 1- xCa x)Cu 3O 8, for R = Er ( x = 0, 0.5) and Ho ( x = 0), has been analyzed by inelastic neutron scattering. Sharp, well-defined transitions of magnetic origin have been observed for the parent R = Er and Ho ( x = 0) compounds. Peaks, determined to be of magnetic origin, have been assigned to crystal-field (CF) transitions within the Russell-Saunders ground multiplet. These results have been modeled using a crystal-field hamiltonian that includes intermediate-coupling and spherical-tensor techniques. The CF potential was determined for tetragonal symmetry. The calculated parameters are similar to those determined for similar R in the RBa 2Cu 3O 7 compounds. The results of the crystal-field analyses for the parent compounds are used to calculate the expected rare-earth contributions to the magnetic susceptibility, and compared to experimental data where available. In contrast to the data on the parent compounds, the spectra obtained from the superconductor Pb 2Sr 2Er 0.5Ca 0.5Cu 3O 8 show only very broad features. This broadening is attributed to chemical disorder rather than to an electronic effect.

  16. Hybrid Laser-Arc Welding of 10-mm-Thick Cast Martensitic Stainless Steel CA6NM: As-Welded Microstructure and Mechanical Properties

    NASA Astrophysics Data System (ADS)

    Mirakhorli, Fatemeh; Cao, Xinjin; Pham, Xuan-Tan; Wanjara, Priti; Fihey, Jean-Luc

    2016-07-01

    Cast CA6NM martensitic stainless steel plates, 10 mm in thickness, were welded using hybrid laser-arc welding. The effect of different welding speeds on the as-welded joint integrity was characterized in terms of the weld bead geometry, defects, microstructure, hardness, ultimate tensile strength, and impact energy. Significant defects such as porosity, root humping, underfill, and excessive penetration were observed at a low welding speed (0.5 m/min). However, the underfill depth and excessive penetration in the joints manufactured at welding speeds above 0.75 m/min met the specifications of ISO 12932. Characterization of the as-welded microstructure revealed untempered martensite and residual delta ferrite dispersed at prior-austenite grain boundaries in the fusion zone. In addition, four different heat-affected zones in the weldments were differentiated through hardness mapping and inference from the Fe-Cr-Ni ternary phase diagram. The tensile fracture occurred in the base metal for all the samples and fractographic analysis showed that the crack path is within the martensite matrix, along primary delta ferrite-martensite interfaces and within the primary delta ferrite. Additionally, Charpy impact testing demonstrated slightly higher fracture energy values and deeper dimples on the fracture surface of the welds manufactured at higher welding speeds due to grain refinement and/or lower porosity.

  17. Hybrid Laser-Arc Welding of 10-mm-Thick Cast Martensitic Stainless Steel CA6NM: As-Welded Microstructure and Mechanical Properties

    NASA Astrophysics Data System (ADS)

    Mirakhorli, Fatemeh; Cao, Xinjin; Pham, Xuan-Tan; Wanjara, Priti; Fihey, Jean-Luc

    2016-04-01

    Cast CA6NM martensitic stainless steel plates, 10 mm in thickness, were welded using hybrid laser-arc welding. The effect of different welding speeds on the as-welded joint integrity was characterized in terms of the weld bead geometry, defects, microstructure, hardness, ultimate tensile strength, and impact energy. Significant defects such as porosity, root humping, underfill, and excessive penetration were observed at a low welding speed (0.5 m/min). However, the underfill depth and excessive penetration in the joints manufactured at welding speeds above 0.75 m/min met the specifications of ISO 12932. Characterization of the as-welded microstructure revealed untempered martensite and residual delta ferrite dispersed at prior-austenite grain boundaries in the fusion zone. In addition, four different heat-affected zones in the weldments were differentiated through hardness mapping and inference from the Fe-Cr-Ni ternary phase diagram. The tensile fracture occurred in the base metal for all the samples and fractographic analysis showed that the crack path is within the martensite matrix, along primary delta ferrite-martensite interfaces and within the primary delta ferrite. Additionally, Charpy impact testing demonstrated slightly higher fracture energy values and deeper dimples on the fracture surface of the welds manufactured at higher welding speeds due to grain refinement and/or lower porosity.

  18. Spectroscopic investigation of 2.02 {mu}m emission in Ho{sup 3+}/Tm{sup 3+} codoped transparent glass ceramic containing CaF{sub 2} nanocrystals

    SciTech Connect

    Chen, Q. J.; Zhang, W. J.; Qian, Q.; Yang, Z. M.; Zhang, Q. Y.

    2010-05-15

    Tm{sup 3+} and Ho{sup 3+} codoped transparent glass ceramic (GC) containing CaF{sub 2} nanocrystals were fabricated by melt-quenching and subsequent thermal treatment. X-ray diffraction and transmission electron microscopy analysis confirmed the precipitation of CaF{sub 2} nanocrystals among the glass matrix. Energy-dispersive x-ray spectroscopy results evidenced the incorporation of Tm{sup 3+} and Ho{sup 3+} into the CaF{sub 2} nanocrystals. Judd-Ofelt parameters were calculated based on the absorption spectra, the smaller {Omega}{sub 2} and larger {Omega}{sub 6} imply that Tm{sup 3+} and Ho{sup 3+} ions has entered into a symmetrical ionic crystal field. 2.02 {mu}m emission spectral of the GC samples were recorded at room temperature with an excitation of 808 nm laser diode. The enhancement of the emission at 2.02 {mu}m in the GC samples could be attributed to more efficient cross relaxation process of Tm{sup 3+}:{sup 3}H{sub 4+}Tm{sup 3+}:{sup 3}H{sub 6}{yields}{sup 2}Tm{sup 3+}:{sup 3}H{sub 4}, and energy transfer from Tm{sup 3+} to Ho{sup 3+} benefited from the incorporation of rare earth ions into CaF{sub 2} nanocrystals.

  19. Preliminary Experiments and Determination of the Thermal Gradient in a 12.7 mm CaF2 Furnace Assembly, Humboldt State University Piston-Cylinder Laboratory

    NASA Astrophysics Data System (ADS)

    Schwab, B. E.

    2004-12-01

    A 12.7 mm piston-cylinder laboratory has been established at Humboldt State University. A series of double-thermocouple (DTC) experiments were performed to measure the thermal profile of the furnace assembly following the procedures of Pickering et al. (1998, Amer. Min.). Furnace assemblies consist of a 304 stainless base plug, CaF&_{2} sleeve, straight-walled graphite heater tube, crushable MgO inner parts, and lower graphite plug and ring which allow for extrusion of the graphite heater tube during shortening of the sleeve and MgO pieces. Careful measurement of pre- and post-run assembly parts indicate an average 30-35% shortening of the assembly. DTC results show a thermal peak that is displaced \\sim2.0 mm above the center of the effective furnace, defined as the length of inner MgO pieces post-run. This offset is in the same direction (upward, toward base plug), but slightly less than the offset described by Pickering et al. (1998). A secondary measure of the thermal profile using spinel growth via reaction between MgO and Al_{2}O_{3} assembly parts (e.g., Watson et al., 2002, CMP) is underway. A single partial melting experiment was performed at 1.0 GPa and 1330\\degC for 72 hours using intermediate peridotite starting material INT-A in a graphite-lined Pt capsule with vitreous carbon spheres as a melt sink. Phase compositions were determined by electron microprobe and mass balance calculations were made to determine melt fraction and mineral mode. Initial calculations yield glass:olivine:cpx:opx:spinel proportions of: 5.0:54.2:15.9:23.9:1.1. These preliminary results correspond well with previous work performed at the University of Oregon on the same starting material (Schwab and Johnston, 2001). The best match is with a 1315\\degC experiment (INT-A13) in terms of mode (6.9:53.7:13.4:25.0:1.0) and glass composition, indicating that the temperature of this initial experiment may be slightly cooler than the target temperature, however the results of this

  20. Production cross sections of elements near the N=126 shell in Ca48-induced reactions with Gd154,Tb159,Dy162, and Ho165 targets

    NASA Astrophysics Data System (ADS)

    Mayorov, D. A.; Werke, T. A.; Alfonso, M. C.; Bennett, M. E.; Folden, C. M.

    2014-08-01

    Excitation functions for shell-stabilized evaporation residues produced in Ca48-induced reactions with Gd154,Tb159,Dy162, and Ho165 targets have been measured in experiments performed at the Cyclotron Institute at Texas A&M University. The examined energy range predominantly covers the 3n and 4n evaporation channels with higher cross sections measured for the 4n products. The σ4n are nearly invariant within experimental uncertainty in reactions with Tb159,Dy162, and Ho165 with the maxima at 12.6 ± 1.9, 12.6 ± 1.7, and 9.4 ± 1.3 mb, respectively. For the reaction with Gd154, the maximum is slightly lower at 4.0 ± 0.6 mb. A simple model to describe the measured production cross sections was employed. Capture was estimated by using the "diffused barrier formula" from the "fusion by diffusion" model proposed by Świątecki et al. [Phys. Rev. C 71, 014602 (2005)]., 10.1103/PhysRevC.71.014602 The fusion probability was estimated by using a phenomenological expression presented by Siwek-Wilczyńska et al. [Int. J. Mod. Phys. E 17, 12 (2008)]., 10.1142/S0218301308009501 The survival probability was calculated according to the formula of Vandenbosch and Huizenga [Nuclear Fission (Academic, New York, 1973)], derived from transition-state theory. The best agreement is reached between calculation and experiment upon inclusion of collective effects in the calculation of the survival probability, shown previously to be important for production of weakly deformed nuclei. This, in turn, challenges the expectation that strong shell stabilization benefits the production cross section. The present data are compared with earlier studies on production of neutron-deficient nuclei in Ca-induced reactions with lanthanide targets.

  1. Large-scale QM/MM calculations of the CaMn4O5 cluster in the oxygen-evolving complex of photosystem II: Comparisons with EXAFS structures

    NASA Astrophysics Data System (ADS)

    Shoji, Mitsuo; Isobe, Hiroshi; Nakajima, Takahito; Yamaguchi, Kizashi

    2016-08-01

    Large-scale QM/MM calculations including hydrogen-bonding networks in the oxygen evolving complex (OEC) of photosystem II (PSII) were performed to elucidate the geometric structures of the CaMn4O5 cluster in the key catalytic states (Si (i = 0-3)). The optimized Mn-Mn, Ca-Mn and Mn-O distances by the large-scale QM/MM starting from the high-resolution XRD structure were consistent with those of the EXAFS experiments in the dark stable S1 state by the Berkeley and Berlin groups. The optimized geometrical parameters for other Si (i = 0, 2, 3) states were also consistent with those of EXAFS, indicating the importance of the large-scale QM/MM calculations for the PSII-OEC.

  2. K-MM radiative Auger effect in solid Ca, Ti and Cr targets after ionization with 0.7-1.5 MeV protons

    NASA Astrophysics Data System (ADS)

    Budnar, M.; Mühleisen, A.; Hribar, M.; Janžekovič, H.; Ravnikar, M.; Šmit, Ž.; Žitnik, M.

    1992-03-01

    Radiative Auger (RAE) X-ray spectra were measured for the first time on Ca, Cr, and Ti targets after ionization by 0.7-1.5 MeV protons. The energies of the RAE X-ray transitions were compared with the energies obtained from the Auger transitions. The RAE intensities relative to the diagram K β13 line were deduced and compared with the available data from X-ray fluorescence and electron capture ionization. The relative yields obtained for Ca, Ti, and Cr were (3.14 ± 0.47), (2.44 ± 0.37) and (2.91 ± 0.58)%, respectively.

  3. Vacuum ultraviolet and near-infrared excited luminescence properties of Ca{sub 3}(PO{sub 4}){sub 2}:RE{sup 3+}, Na{sup +} (RE=Tb, Yb, Er, Tm, and Ho)

    SciTech Connect

    Zhang Jia; Wang Yuhua; Guo Linna; Zhang Feng; Wen Yan; Liu Bitao; Huang Yan

    2011-08-15

    Tb{sup 3+}, Yb{sup 3+}, Tm{sup 3+}, Er{sup 3+}, and Ho{sup 3+} doped Ca{sub 3}(PO{sub 4}){sub 2} were synthesized by solid-state reaction, and their luminescence properties were studied by spectra techniques. Tb{sup 3+}-doped samples can exhibit intense green emission under VUV excitation, and the brightness for the optimal Tb{sup 3+} content is comparable with that of the commercial Zn{sub 2}SiO{sub 4}:Mn{sup 2+} green phosphor. Under near-infrared laser excitation, the upconversion luminescence spectra of Yb{sup 3+}, Tm{sup 3+}, Er{sup 3+}, and Ho{sup 3+} doped samples demonstrate that the red, green, and blue tricolored fluorescence could be obtained by codoping Yb{sup 3+}-Ho{sup 3+}, Yb{sup 3+}-Er{sup 3+}, and Yb{sup 3+}-Tm{sup 3+} in Ca{sub 3}(PO{sub 4}){sub 2}, respectively. Good white upconversion emission with CIE chromaticity coordinates (0.358, 0.362) is achieved by quadri-doping Yb{sup 3+}-Tm{sup 3+}-Er{sup 3+}-Ho{sup 3+} in Ca{sub 3}(PO{sub 4}){sub 2}, in which the cross-relaxation process between Er{sup 3+} and Tm{sup 3+}, producing the {sup 1}D{sub 2}-{sup 3}F{sub 4} transition of Tm{sup 3+}, is found. The upconversion mechanisms are elucidated through the laser power dependence of the upconverted emissions and the energy level diagrams. - Graphical abstract: The CPO:0.25Tb{sup 3+}, 0.25Na{sup +} exhibits a comparable brightness to the commercial Zn{sub 2}SiO{sub 4}:Mn{sup 2+} upon 147 nm excitation. Good white light color is achieved in CPO:Yb{sup 3+}-Tm{sup 3+}-Er{sup 3+}-Ho{sup 3+} under 980 nm excitation. Highlights: > Ca{sub 3}(PO{sub 4}){sub 2}:Tb{sup 3+},Na{sup +} exhibits a comparable brightness with commercial Zn{sub 2}SiO{sub 4}:Mn{sup 2+}. > Red, green and blue colors are achieved in Yb{sup 3+}, Ho{sup 3+}, Er{sup 3+}, Tm{sup 3+} doped Ca{sub 3}(PO{sub 4}){sub 2}. > Good white emission is obtained in Yb{sup 3+}-Ho{sup 3+}-Er{sup 3+}-Tm{sup 3+} quadri-doped Ca{sub 3}(PO{sub 4}){sub 2}. > Ca{sub 3}(PO{sub 4}){sub 2}:Tb{sup 3+}, Yb{sup 3+}, Ho

  4. The layered antimonides RELi3Sb2 (RE=Ce-Nd, Sm, Gd-Ho). Filled derivatives of the CaAl2Si2 structure type

    NASA Astrophysics Data System (ADS)

    Schäfer, Marion C.; Suen, Nian-Tzu; Raglione, Michaella; Bobev, Svilen

    2014-02-01

    Reported are the synthesis and the structural characterization of an extended family of rare-earth metal-lithium-antimonides with the formula RELi3Sb2 (RE=Ce-Nd, Sm, Gd-Ho). They crystallize in the trigonal space group P3barm1 (No. 164, Pearson symbol hP6) with a structure, best viewed as a filled derivative of the common CaAl2Si2 structure type (ternary variant of α-La2O3). Across the series, the lattice parameters monotonically decrease, following the lanthanide contraction. Temperature-dependent magnetic susceptibility measurements for CeLi3Sb2, PrLi3Sb2 and TbLi3Sb2 reveal paramagnetic behavior in the high temperature range, and the obtained effective moments are consistent with the expected ones for the free-ion RE3+ ground state. Possible ferromagnetic ordering for PrLi3Sb2 and antiferromagnetic ordering for TbLi3Sb2 are observed in the low temperature range (below 20 K). Tight-binding muffin-tin orbital electronic band structure calculations for LaLi3Sb2 are presented and discussed as well.

  5. Improved ferroelectric/piezoelectric properties and bright green/UC red emission in (Li,Ho)-doped CaBi4Ti4O15 multifunctional ceramics with excellent temperature stability and superior water-resistance performance.

    PubMed

    Xiao, Ping; Guo, Yongquan; Tian, Mijie; Zheng, Qiaoji; Jiang, Na; Wu, Xiaochun; Xia, Zhiguo; Lin, Dunmin

    2015-10-21

    Multifunctional materials based on rare earth ion doped ferro/piezoelectrics have attracted considerable attention in recent years. In this work, new lead-free multifunctional ceramics of Ca1-x(LiHo)x/2Bi4Ti4O15 were prepared by a conventional solid-state reaction method. The great multi-improvement in ferroelectricity/piezoelectricity, down/up-conversion luminescence and temperature stability of the multifunctional properties is induced by the partial substitution of (Li0.5Ho0.5)(2+) for Ca(2+) ions in CaBi4Ti4O15. All the ceramics possess a bismuth-layer structure, and the crystal structure of the ceramics is changed from a four layered bismuth-layer structure to a three-layered structure with the level of (Li0.5Ho0.5)(2+) increasing. The ceramic with x = 0.1 exhibits simultaneously, high resistivity (R = 4.51 × 10(11)Ω cm), good piezoelectricity (d33 = 10.2 pC N(-1)), high Curie temperature (TC = 814 °C), strong ferroelectricity (Pr = 9.03 μC cm(-2)) and enhanced luminescence. These behaviours are greatly associated with the contribution of (Li0.5Ho0.5)(2+) in the ceramics. Under the excitation of 451 nm light, the ceramic with x = 0.1 exhibits a strong green emission peak centered at 545 nm, corresponding to the transition of the (5)S2→(5)I8 level in Ho(3+) ions, while a strong red up-conversion emission band located at 660 nm is observed under the near-infrared excitation of 980 nm at room temperature, arising from the transition of (5)F5→(5)I8 levels in Ho(3+) ions. Surprisingly, the excellent temperature stability of ferroelectricity/piezoelectricity/luminescence and superior water-resistance behaviors of piezoelectricity/luminescence are also obtained in the ceramic with x = 0.1. Our study suggests that the present ceramics may have potential applications in advanced multifunctional devices at high temperature. PMID:26387782

  6. 2,3-Dimethoxy-2′-hydroxychalcone ameliorates TNF-α-induced ICAM-1 expression and subsequent monocyte adhesiveness via NF-kappaB inhibition and HO-1 induction in HaCaT cells

    PubMed Central

    Kim, Hyejin; Youn, Gi Soo; An, Soo Yeon; Kwon, Hyeok Yil; Choi, Soo Young; Park, Jinseu

    2016-01-01

    Up-regulation of adhesion molecules plays an important role in the infiltration of leukocytes into the skin during the development of various inflammatory skin diseases, such as atopic dermatitis. In this study, we investigated the modulatory effects of 2,3-dimethoxy-2′-hydroxychalcone (DMHC) on tumor necrosis factor (TNF)-α-induced intercellular adhesion molecule-1 (ICAM-1) expression and monocyte adhesiveness, as well as the molecular mechanisms underlying its action in the HaCaT human keratinocyte cell line. Pre-treating HaCaT cells with DMHC significantly suppressed TNF-α-induced ICAM-1 expression and subsequent monocyte adhesiveness. DMHC inhibited TNF-α-induced activation of NF-ᴋB. In addition, DMHC induced HO-1 expression as well as NRF2 activation. Furthermore, HO-1 knockdown using siRNA reversed the inhibitory effect of DMHC on TNF-α-induced ICAM-1 expression and adhesion of monocytes to keratinocytes. These results suggest that DMHC may inhibit TNF-α-induced ICAM-1 expression and adhesion of monocytes to keratinocytes by suppressing the signaling cascades leading to NF-ᴋB activation and inducing HO-1 expression in keratinocytes. [BMB Reports 2016; 49(1): 57-62] PMID:26277982

  7. Luminescence Properties of Self-Activated Mm(VO4)2 (M = Mg, Ca, Sr, and Ba) Phosphors Synthesized by Solid-State Reaction Method.

    PubMed

    Min, Xin; Huang, Zhaohui; Fang, Minghao; Liu, Yan'gai; Tang, Chao; Wu, Xiaowen

    2016-04-01

    In this paper, M3(VO4)2 (M = Mg, Ca, Sr, and Ba) self-activated phosphors were prepared by a solid-state reaction method at 1,000 °C for 5 h. The phase formation and micrographs were analyzed by X-ray diffraction and scanning electron microscopy. The Ca3(VO4)2 phosphor does not show any emission peaks under excitation with ultraviolet (UV) light. However, the M3(VO4)2 (M = Mg, Sr, and Ba) samples are effectively excited by UV light chips ranging from 200 nm to 400 nm and exhibit broad emission bands due to the charge transfer from the oxygen 2p orbital to the vacant 3d orbital of the vanadium in the VO4. The color of these phosphors changes from yellow to light blue via blue-green with increasing ionic radius from Mg to Sr to Ba. The luminescence lifetimes and quantum yield decrease with the increasing unit cell volume and V-V distance, in the order of Mg3(VO4)2 to Sr3(VO4)2 to Ba3(VO4)2. The emission intensity decreases with the increase of temperatures, but presents no color shift. This confirms that these self-activated M3(VO4)2 phosphors can be suggested as candidates of the single-phase phosphors for light using UV light emitting diodes (LEDs). PMID:27451689

  8. Effects of extracellular pH on receptor-mediated Ca2+ influx in A7r5 rat smooth muscle cells: involvement of two different types of channel.

    PubMed Central

    Iwasawa, K; Nakajima, T; Hazama, H; Goto, A; Shin, W S; Toyo-oka, T; Omata, M

    1997-01-01

    1. The effects of extracellular pH (pHo) on receptor (vasopressin or endothelin-1)-mediated Ca2- entry and Ca(2+)-permeable channels were investigated in aortic smooth muscle cells (A7r5) from rat embryonic thoracic aorta. Intracellular Ca2+ ([Ca2+]i) was measured using fura-2 AM and whole-cell voltage clamp techniques were employed. 2. Vasopressin and endothelin-1 (100 nM) in the presence of nicardipine (10 microM) evoked a sustained rise in [Ca2+]i due to calcium entry. Extracellular acidosis decreased receptor (vasopressin or endothelin-1)-mediated Ca2+ entry, while extracellular alkalosis potentiated it. 3. Depletion of intracellular Ca2+ stores with thapsigargin (1 microM) also evoked Ca2+ entry activated by emptying of intracellular Ca2+ stores (capacitative Ca2+ entry). Extracellular acidosis decreased this capacitative Ca2+ entry, while extracellular alkalosis potentiated it. 4. Under voltage-clamp conditions with Ca+ internal solution, vasopressin and endothelin-1 activated non-selective cation currents (ICAT). Ba2+ or Ca2+ were also charge carriers of ICAT. Reducing the pHo inhibited ICAT, while increasing pHo potentiated it in a reversible manner. 5. Intracellular pH (pHi) changes did not cause the same marked effects as pHo changes, and a high concentration of Hepes (50 mM) in the patch pipette did not inhibit the effects of pHo on ICAT. 6. Similar results were obtained when ICAT was activated by GTP gamma S (1 mM) applied through the patch pipette, even in the absence of agonists, probably because of direct activation of GTP-binding proteins coupled to the receptors. 7. In cells treated with thapsigargin, addition of Ca2+ to the bath solution induced Ca(2+)-dependent K+ currents activated by capacitative Ca2+ entry. However, no measurable ionic currents activated by capacitative Ca2+ entry (ICRAC) were observed under conditions with Cs+ internal solution and EGTA (5 mM), although vasopressin still activated ICAT. 8. These results suggest that the

  9. Structure, magnetism and transport of the perovskite manganites Ln {sub 0.5}Ca{sub 0.5}MnO{sub 3} (Ln=Ho, Er, Tm, Yb and Lu)

    SciTech Connect

    Yoshii, Kenji . E-mail: yoshiike@spring8.or.jp; Abe, Hideki; Ikeda, Naoshi

    2005-12-15

    It was found that the manganese perovskite oxides Ln {sub 0.5}Ca{sub 0.5}MnO{sub 3} (Ln=Ho, Er, Tm, Yb and Lu) have an orthorhombic structure (space group Pnma). The Mn-O-Mn angles were calculated to be {approx}148-150{sup o}, revealing an existence of a large crystallographic distortion in these oxides. Electrical resistivity measurements indicated both an insulating nature and a small magnetoresistance effect, both of which are owing to narrow bandwidths of the Mn-3d electrons arising from the crystallographic distortion. DC magnetization measurements showed the three characteristic temperatures, which could be assigned to charge-order, antiferromagnetism of Mn moments, and possible glassy states. All of these temperatures were decreased for the heavier Ln ions, which is explained in connection with both a difference of ionic radii of Ln {sup 3+} and Ca{sup 2+}, and a lowering of electron transfer. The charge-ordering transition was not clearly observed only for Lu{sub 0.5}Ca{sub 0.5}MnO{sub 3} containing the smallest lanthanide ion, plausibly due to a large randomness of magnetic interactions arising from the ionic radii difference of Lu{sup 3+} and Ca{sup 2+}. In addition, preliminary measurements of AC dielectric response suggested that these manganites belong to a so-called multiferroic system.

  10. 8mm/16mm Movie-Making.

    ERIC Educational Resources Information Center

    Provisor, Henry

    The materials, techniques, and attitudes needed to make professional-quality movies using 8mm., super 8mm., and 16mm. amateur equipment are covered in this guide to movie-making. The pros and cons are discussed of the various makes and models of cameras and lenses. Other topics discussed are: exposure and lighting, choosing film, camera speed and…

  11. The layered antimonides RELi{sub 3}Sb{sub 2} (RE=Ce–Nd, Sm, Gd–Ho). Filled derivatives of the CaAl{sub 2}Si{sub 2} structure type

    SciTech Connect

    Schäfer, Marion C.; Suen, Nian-Tzu; Raglione, Michaella; Bobev, Svilen

    2014-02-15

    Reported are the synthesis and the structural characterization of an extended family of rare-earth metal–lithium–antimonides with the formula RELi{sub 3}Sb{sub 2} (RE=Ce–Nd, Sm, Gd–Ho). They crystallize in the trigonal space group P3{sup ¯}m1 (No. 164, Pearson symbol hP6) with a structure, best viewed as a filled derivative of the common CaAl{sub 2}Si{sub 2} structure type (ternary variant of α-La{sub 2}O{sub 3}). Across the series, the lattice parameters monotonically decrease, following the lanthanide contraction. Temperature-dependent magnetic susceptibility measurements for CeLi{sub 3}Sb{sub 2}, PrLi{sub 3}Sb{sub 2} and TbLi{sub 3}Sb{sub 2} reveal paramagnetic behavior in the high temperature range, and the obtained effective moments are consistent with the expected ones for the free-ion RE{sup 3+} ground state. Possible ferromagnetic ordering for PrLi{sub 3}Sb{sub 2} and antiferromagnetic ordering for TbLi{sub 3}Sb{sub 2} are observed in the low temperature range (below 20 K). Tight-binding muffin-tin orbital electronic band structure calculations for LaLi{sub 3}Sb{sub 2} are presented and discussed as well. - Graphical abstract: The large family of rare-earth metal–lithium–antimonides with the formula RELi{sub 3}Sb{sub 2} (RE=Ce–Nd, Sm, Gd–Ho) crystallize in the trigonal space group P3{sup ¯}m1 (No. 164, Pearson symbol hP6) with a structure that is a filled derivative of the CaAl{sub 2}Si{sub 2} structure type (ternary variant of α-La{sub 2}O{sub 3}). Display Omitted - Highlights: • RELi{sub 3}Sb{sub 2} (RE=Ce–Nd, Sm, Gd–Ho) constitute an extended family of rare-earth metal–lithium–antimonides. • The layered structure is a filled derivative of the common CaAl{sub 2}Si{sub 2} structure type. • The valence electron count follows the Zintl–Klemm rules. • Electronic band structure calculations for LaLi{sub 3}Sb{sub 2} indicate small band-gap semiconducting behavior.

  12. Efficient, low threshold, cryogenic Ho:YAG laser.

    PubMed

    Ganija, Miftar; Simakov, Nikita; Hemming, Alexander; Haub, John; Veitch, Peter; Munch, Jesper

    2016-05-30

    We report the development of an efficient, liquid-nitrogen conduction cooled Ho:YAG slab laser with good beam quality. Detailed measurements resolving the structure of the 1900-1911 nm absorption band in Ho:YAG at 77 K are presented. Stress-free conduction cooled mounting of the Ho:YAG slab was demonstrated and the resulting laser operated with a large mode volume of 42 mm3, a slope efficiency of 75% and a threshold of 0.84 W. To our knowledge this corresponds to the lowest reported threshold intensity for a Ho:YAG laser. PMID:27410084

  13. mm-wave antenna

    NASA Astrophysics Data System (ADS)

    Muhs, H. P.

    1985-07-01

    The present low profile seeker front end's slotted waveguide antenna was primarily developed to investigate the feasibility of the application of standard manufacturing techniques to mm-wave hardware. A dual plane monopulse comparator was constructed to mate with the antenna via integrated packaging techniques. The comparator was fabricated by CAD/CAM milling operations.

  14. Controlled synthesis and luminescence properties of Ca0.5Y1-x(MoO4)2:xRE3+ (RE = Eu, Pr, Sm, Tb, Dy, Yb/Er, Yb/Tm, and Yb/Ho) phosphors by hydrothermal method versus pulsed laser deposition

    NASA Astrophysics Data System (ADS)

    Mahalingam, Venkatakrishnan; Thirumalai, Jagannathan; Krishnan, Rajagopalan; Chandramohan, Rathinam

    2016-01-01

    Herein, we report on rare-earth (RE) activated Ca0.5Y1-x(MoO4)2:xRE3+ (RE = Eu, Pr, Sm, Tb, Dy, Yb/Er, Yb/Ho, and Yb/Tm) phosphors synthesized using a surfactant-mediated hydrothermal route. Timedependent experiments were performed, and the morphological evolution of the phosphors was studied. From prepared powder samples of Ca0.5Y1-x(MoO4)2:xRE3+ (RE = Eu and Yb/Er), nano-sized thin phosphor films were grown using pulsed laser deposition (PLD). The surface topography of the as-grown thin phosphor films was analyzed. The asprepared phosphors were characterized by structural and optical studies. The powder phosphor exhibited bi pyramid-like micro-architectures. Structural studies indicated that Ca0.5Y1-x(MoO4)2 possesses the scheelite tetragonal crystal structure. The down-conversion luminescence of Ca0.5Y1-x(MoO4)2:xRE3+ (RE = Eu, Pr, Sm, Tb, and Dy) as powder phosphors and Eu3+ doped Ca0.5Y1-x(MoO4)2 thin phosphor film were studied. Upon irradiation with a 980 nm laser, the Ca0.5Y1-x(MoO4)2: xRE3+ (RE = Yb/Er, Yb/Ho, and Yb/Tm) powder phosphors and Ca0.5Y1-x(MoO4)2:xRE3+ (RE = Yb/Er) thin phosphor film showed intense up-converted visible emissions in green, yellow, and blue regions. The fluorescence decay time and color co-ordinates were determined for all synthesized phosphors. From the obtained results, the prepared powder and thin film phosphors are suggested to be suitable candidates for display and electro-luminescence applications. [Figure not available: see fulltext.

  15. Building 904, oblique view to northeast, 210mm lens Travis ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Building 904, oblique view to northeast, 210mm lens - Travis Air Force Base, Base Spares Warehouse No. 1, Dixon Avenue & W Street, Armed Forces Special Weapons Project Q Area, Fairfield, Solano County, CA

  16. Building 909, oblique view to southeast, 135 mm lens. Building ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Building 909, oblique view to southeast, 135 mm lens. Building 908 at extreme right for context. - Travis Air Force Base, Handling Crew Building, North of W Street, Armed Forces Special Weapons Project Q Area, Fairfield, Solano County, CA

  17. Building 904, oblique view to southeast, 135 mm lens. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Building 904, oblique view to southeast, 135 mm lens. - Travis Air Force Base, Base Spares Warehouse No. 1, Dixon Avenue & W Street, Armed Forces Special Weapons Project Q Area, Fairfield, Solano County, CA

  18. Building 904, oblique view to northwest, 135 mm lens ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Building 904, oblique view to northwest, 135 mm lens - Travis Air Force Base, Base Spares Warehouse No. 1, Dixon Avenue & W Street, Armed Forces Special Weapons Project Q Area, Fairfield, Solano County, CA

  19. Building 1204, oblique view to east, 90 mm lens. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Building 1204, oblique view to east, 90 mm lens. - Travis Air Force Base, Squadron Operations & Readiness Crew Facility, W Street, Armed Forces Special Weapons Project Q Area, Fairfield, Solano County, CA

  20. Building 931, oblique view to southeast, 135 mm lens. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Building 931, oblique view to southeast, 135 mm lens. - Travis Air Force Base, Central Battery Charging Building, North of W Street, Armed Forces Special Weapons Project Q Area, Fairfield, Solano County, CA

  1. Building 1204, oblique view to west, 135 mm lens. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Building 1204, oblique view to west, 135 mm lens. - Travis Air Force Base, Squadron Operations & Readiness Crew Facility, W Street, Armed Forces Special Weapons Project Q Area, Fairfield, Solano County, CA

  2. Building 931, oblique view to northwest, 210 mm lens. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Building 931, oblique view to northwest, 210 mm lens. - Travis Air Force Base, Central Battery Charging Building, North of W Street, Armed Forces Special Weapons Project Q Area, Fairfield, Solano County, CA

  3. Building 932, oblique view to northwest, 90 mm lens. Building ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Building 932, oblique view to northwest, 90 mm lens. Building 933-935 at extreme left. - Travis Air Force Base, Nuclear Weapons Assembly Plant 5, W Street, Armed Forces Special Weapons Project Q Area, Fairfield, Solano County, CA

  4. Quantification of the response of rat medullary raphe neurones to independent changes in pHo and PCO2

    PubMed Central

    Wang, Wengang; Bradley, Stefania Risso; Richerson, George B

    2002-01-01

    The medullary raphe nuclei contain putative central respiratory chemoreceptor neurones that are highly sensitive to acidosis. To define the primary stimulus for chemosensitivity in these neurones, the response to hypercapnic acidosis was quantified and compared with the response to independent changes in PCO2 and extracellular pH (pHo). Neurones from the ventromedial medulla of neonatal rats (P0-P2) were dissociated and maintained in tissue culture for long enough to develop a mature response (up to 70 days). Perforated patch clamp recordings were used to record membrane potential and firing rate while changes were made in pHo, PCO2 and/or [NaHCO3]o from baseline values of 7.4, 5 % and 26 mm, respectively. Hypercapnic acidosis (PCO2 9 %; pHo 7.17) induced an increase in firing rate to 285 % of control in one subset of neurones (‘stimulated neurones’) and induced a decrease in firing rate to 21 % of control in a different subset of neurones (‘inhibited neurones’). Isocapnic acidosis (pHo 7.16; [NaHCO3]o 15 mm) induced an increase in firing rate of stimulated neurones to 309 % of control, and a decrease in firing rate of inhibited neurones to 38 % of control. In a different group of neurones, isohydric hypercapnia (9 % PCO2; [NaHCO3]o 40 mm) induced an increase in firing rate of stimulated neurones by the same amount (to 384 % of control) as in response to hypercapnic acidosis (to 327 % of control). Inhibited neurones also responded to isohydric hypercapnia in the same way as they did to hypercapnic acidosis. In Hepes-buffered solution, both types of neurone responded to changes in pHo in the same way as they responded to changes in pHo in bicarbonate-buffered Ringer solution. It has previously been shown that all acidosis-stimulated neurones in the medullary raphe are immunoreactive for tryptophan hydroxylase (TpOH-ir). Here it was found that TpOH-ir neurones in the medullary raphe were immunoreactive for carbonic anhydrase type II and type IV (CA II and CA

  5. High-spin yrast structure of {sup 159}Ho

    SciTech Connect

    Ollier, J.; Simpson, J.; Riley, M. A.; Wang, X.; Aguilar, A.; Teal, C.; Paul, E. S.; Nolan, P. J.; Petri, M.; Rigby, S. V.; Thomson, J.; Unsworth, C.; Carpenter, M. P.; Janssens, R. V. F.; Lauritsen, T.; Zhu, S.; Darby, I. G.; Hartley, D. J.; Kondev, F. G.

    2011-08-15

    An investigation of the yrast structure of the odd-Z {sup 159}Ho nucleus to high spin has been performed. The {sup 159}Ho nucleus was populated by the reaction {sup 116}Cd({sup 48}Ca,p4n{gamma}) at a beam energy of 215 MeV, and resulting {gamma} decays were detected by the Gammasphere spectrometer. The h{sub 11/2} yrast band has been significantly extended up to I{sup {pi}=}75/2{sup -} (tentatively 79/2{sup -}). A lower frequency limit for the second (h{sub 11/2}){sup 2} proton alignment was extracted consistent with the systematics of this alignment frequency, indicating an increased deformation with neutron number in the Ho isotopes. The energy-level splitting between the signature partners in the h{sub 11/2} structures of the Ho isotopes and the neighboring N=92 isotones is discussed.

  6. Primeval galaxies in the sub-mm and mm

    NASA Technical Reports Server (NTRS)

    Bond, J. Richard; Myers, Steven T.

    1993-01-01

    Although the results of COBE's FIRAS experiment 1 constrain the deviation in energy from the CMB blackbody in the 500-5000 micron range to be delta E/E, sub cmb less than 0.005, primeval galaxies can still lead to a brilliant sub-mm sky of non-Gaussian sources that are detectable at 10 inch resolution from planned arrays such as SCUBA on the James Clerk Maxwell Telescope and, quite plausibly, at sub-arcsecond resolution in planned mm and sub-mm interferometers. Here, we apply our hierarchical peaks method to a CDM model to construct sub-mm and mm maps of bursting PG's appropriate for these instruments with minimum contours chosen to correspond to realistic observational parameters for them and which pass the FIRAS limits.

  7. OpenMM accelerated MMTK

    NASA Astrophysics Data System (ADS)

    Bishop, Kevin P.; Constable, Steve; Faruk, Nabil F.; Roy, Pierre-Nicholas

    2015-06-01

    In this work, we provide an interface developed to link the Molecular Modelling toolkit (MMTK) with OpenMM in order to take advantage of the fast evaluation techniques of OpenMM. This interface allows MMTK scripts using the Langevin dynamics integrator, for both classical and path integral simulations, to be executed on a variety of hardware including graphical processing units via OpenMM. The interface has been developed using Python and Cython to take advantage of the high level abstraction thanks to the MMTK and OpenMM software packages. We have tested the interface on a number of systems to observe which systems benefit most from the acceleration libraries of OpenMM.

  8. SSC 40 mm cable results and 50 mm design discussions

    SciTech Connect

    Christopherson, D.; Capone, D.; Hannaford, R.; Remsbottom, R.; Jayakumar, R.; Snitchler, G. ); Scanlan, R.; Royet, J. )

    1990-09-01

    A summary of the cable produced for the 1990 40 mm Dipole Program is presented. The cable design parameters for the 50 mm Dipole Program are discussed, as well as portions of the SSC specification draft. Considerations leading to the final cable configuration and the results of preliminary trials are included. The first iteration of a strand mapping program to automate cable strand maps is introduced. 7 refs., 2 figs., 1 tab.

  9. 5. East portal of Tunnel 26, view to southwest, 135mm ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. East portal of Tunnel 26, view to southwest, 135mm lens. Tunnel 25 (HAER CA-201) is visible in the distance. - Central Pacific Transcontinental Railroad, Tunnel No. 26, Milepost 133.29, Applegate, Placer County, CA

  10. HOED: Hypermedia Online Educational Database.

    ERIC Educational Resources Information Center

    Duval, E.; Olivie, H.

    This paper presents HOED, a distributed hypermedia client-server system for educational resources. The aim of HOED is to provide a library facility for hyperdocuments that is accessible via the world wide web. Its main application domain is education. The HOED database not only holds the educational resources themselves, but also data describing…

  11. Minfong Ho: Politics in Prose

    ERIC Educational Resources Information Center

    Wiggins, Joy L.

    2006-01-01

    In this article, the author interviews Minfong Ho, an award-winning Thai writer of children's and young adult novels. Ho was born in Burma to Chinese parents in 1951, raised in Singapore and Thailand, educated in Bangkok, Taiwan, and at Cornell University in New York. Ho's first novel, "Sing to the Dawn," won first prize from the Council of…

  12. The GBT 4mm Receiver

    NASA Astrophysics Data System (ADS)

    Frayer, David T.; White, S.; Watts, G.; Stennes, M.; Maddalena, R. J.; Simon, R.; Pospieszalski, M.; Bryerton, E.

    2013-01-01

    The new 4mm receiver (67--93 GHz) for the Robert C. Byrd Green Bank Telescope (GBT) was built to take advantage of the improved surface accuracy of the dish. The low frequency end of the 3mm atmospheric window is not available with ALMA (<84 GHz), and the sensitivity of the GBT is better than any other facility within this band. We discuss the design and performance of this new receiver for the GBT, and highlight the science opportunities available with the instrument. The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc.

  13. Tropospheric HO determination by FAGE

    NASA Astrophysics Data System (ADS)

    Hard, T. M.; Obrien, R. J.; Chan, C. Y.; Mehrabzadeh, A. A.

    1986-12-01

    In the detection of tropospheric HO by laser excited fluorescence, and alternative air-sampling method, named FAGE (Fluorescence Assay with Gas Expansion) was introduced. Here the air is expanded through a nozzle prior to excitation, in order to improve the ratio of the HO signal to the scattered, fluorescent, and photolytic backgrounds. The improvement comes from the differing pressure dependence of the intensities of these four terms, as well as the distinguishability of their temporal waveforms at low pressures when excited by a pulsed laser. HO has been excited by a YAG/dye laser. Other lasers and pumping paths may perform as well or better in this method. With FAGE, chemical modulation of the HO signal was achieved by hydrocarbon addition to the nozzle flow, converting photolytic HO from an interference to a background. Chemical calibration of the instrumental response to external HO was also achieved, by hydrocarbon decay, at HO concentrations within the ambient range.

  14. Apollo 12 photography 70 mm, 16 mm, and 35 mm frame index

    NASA Technical Reports Server (NTRS)

    1970-01-01

    For each 70-mm frame, the index presents information on: (1) the focal length of the camera, (2) the photo scale at the principal point of the frame, (3) the selenographic coordinates at the principal point of the frame, (4) the percentage of forward overlap of the frame, (5) the sun angle (medium, low, high), (6) the quality of the photography, (7) the approximate tilt (minimum and maximum) of the camera, and (8) the direction of tilt. A brief description of each frame is also included. The index to the 16-mm sequence photography includes information concerning the approximate surface coverage of the photographic sequence and a brief description of the principal features shown. A column of remarks is included to indicate: (1) if the sequence is plotted on the photographic index map and (2) the quality of the photography. The pictures taken using the lunar surface closeup stereoscopic camera (35 mm) are also described in this same index format.

  15. Variable Selection using MM Algorithms

    PubMed Central

    Hunter, David R.; Li, Runze

    2009-01-01

    Variable selection is fundamental to high-dimensional statistical modeling. Many variable selection techniques may be implemented by maximum penalized likelihood using various penalty functions. Optimizing the penalized likelihood function is often challenging because it may be nondifferentiable and/or nonconcave. This article proposes a new class of algorithms for finding a maximizer of the penalized likelihood for a broad class of penalty functions. These algorithms operate by perturbing the penalty function slightly to render it differentiable, then optimizing this differentiable function using a minorize-maximize (MM) algorithm. MM algorithms are useful extensions of the well-known class of EM algorithms, a fact that allows us to analyze the local and global convergence of the proposed algorithm using some of the techniques employed for EM algorithms. In particular, we prove that when our MM algorithms converge, they must converge to a desirable point; we also discuss conditions under which this convergence may be guaranteed. We exploit the Newton-Raphson-like aspect of these algorithms to propose a sandwich estimator for the standard errors of the estimators. Our method performs well in numerical tests. PMID:19458786

  16. Credit USAF, ca. 1945. Original housed in the Photograph Files, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Credit USAF, ca. 1945. Original housed in the Photograph Files, AFFTC/HO, Edwards AFB, California. Early view of the Control Tower (designated T-65, Building 4500) fitted out with radio antennae. Structure at base of tower was T42 (later Building 4503), Flight Operations - Edwards Air Force Base, North Base, Radio & Control Tower T-65, Northeast of A Street, Boron, Kern County, CA

  17. Credit USAF, ca. 1943. Original housed in the Photograph Files, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Credit USAF, ca. 1943. Original housed in the Photograph Files, AFFTC/HO, Edwards AFB, California. Historic view of finished swimming pool, with fence and lifeguard station. View looks west - Edwards Air Force Base, North Base, Swimming Pool, Second Street, Boron, Kern County, CA

  18. Spectral and lasing characteristics of 1% Ho:YAG ceramics under intracavity pumping

    SciTech Connect

    Bagayev, S N; Vatnik, S M; Vedin, I A; Kurbatov, P F; Osipov, V V; Shitov, V A; Maksimov, R N; Luk'yashin, K E; Pavlyuk, A A

    2015-01-31

    High-transparency 1% Ho:YAG ceramics with the transmission coefficient of 82% in the IR range at the sample thickness of 1 mm are synthesised from a mixture of the Ho:Y{sub 2}O{sub 3} and Al{sub 2}O{sub 3} nanopowders obtained by the laser method. Results of investigations of spectral and lasing characteristics of 1 % Ho:YAG ceramics under intracavity pumping by radiation of a 5% Tm:KLuW disk element are presented. Based on spectral intensity analysis of generation in the 1.8 – 2.1 mm range and on cavity parameters, the estimated lasing slope efficiency for 1% Ho:YAG ceramics is about 40%. (lasers)

  19. Solar-pumped Er,Tm,Ho:YAG laser

    SciTech Connect

    Benmair, R.M.J.; Kagan, J.; Kalisky, Y.; Noter, Y.; Oron, M.; Shimony, Y.; Yogev, A. )

    1990-01-01

    Direct solar illumination was used to pump a 5-mm-diameter 62-mm exposed-length rod of Er,Tm,Ho:YAG to achieve a quasi-cw lasing of the Ho ion at an average power of 12 W. The solar radiation was chopped at a 20% duty cycle to avoid overloading of the cooling system. The peak power output was more than 65 W during the chopper's open times. The slope efficiency is 3.8%, and the threshold input energy is approximately 100 W. The laser was operated for long times (up to hours) while maintaining its performance. This is, to our knowledge, the first directly solar-pumped laser operating at 77 K.

  20. HO:LULF and HO:LULF Laser Materials

    NASA Technical Reports Server (NTRS)

    Barnes, Norman P. (Inventor); Morrison, Clyde A. (Inventor); Filer, Elizabeth D. (Inventor); Jani, Mahendra G. (Inventor); Murray, Keith E. (Inventor); Lockard, George E. (Inventor)

    1998-01-01

    A laser host material LULF (LuLiF4) is doped with holmium (Ho) and thulium (Tm) to produce a new laser material that is capable of laser light production in the vicinity of 2 microns. The material provides an advantage in efficiency over conventional Ho lasers because the LULF host material allows for decreased threshold and upconversion over such hosts as YAG and YLF. The addition of Tm allows for pumping by commonly available GaAlAs laser diodes. For use with flashlamp pumping, erbium (Er) may be added as an additional dopant. For further upconversion reduction, the Tm can be eliminated and the Ho can be directly pumped.

  1. Apollo 12 70 mm photographic catalog

    NASA Technical Reports Server (NTRS)

    1970-01-01

    Proof prints of the 70-mm photography are presented, sorted by magazine and frame number. The 28 lunar surface panorama mosaics and a listing of the mosaics are included. The catalog is designed to be used in conjunction with the "Apollo 12 Photography: 70-mm, 16-mm, and 35-mm Frame Index', which makes it possible to locate the area covered by each frame.

  2. Investigation on the structure and upconversion fluorescence of Yb3+/Ho3+ co-doped fluorapatite crystals for potential biomedical applications

    PubMed Central

    Li, Xiyu; Zhu, Jingxian; Man, Zhentao; Ao, Yingfang; Chen, Haifeng

    2014-01-01

    Rare-earth Yb3+ and Ho3+ co-doped fluorapatite (FA:Yb3+/Ho3+) crystals were prepared by hydrothermal synthesis, and their structure, upconversion properties, cell proliferation and imaging were investigated. The synthesized crystals, with a size of 16 by 286 nm, have a hexagonal crystal structure of classic FA and a Ca/Yb/Ho molar ratio of 100/16/2.1. Several reasonable Yb3+/Ho3+ -embedding lattice models along the fluorine channel of the FA crystal cell are proposed for the first time, such as models for (Ca7YbHo©)(PO4)6F2 and (Ca6YbHoNa2)(PO4)6F2. The activated FA:Yb3+/Ho3+ crystals were found to exhibit distinct upconversion fluorescence. The 543- and 654-nm signals in the emission spectra could be assigned, respectively, to the 5F4 (5S2) - 5I8 and 5F5 - 5I8 transitions of holmium via 980-nm near-infrared excitation and the energy transfer of ytterbium. After the surfaces were grafted with hydrophilic dextran, the crystals displayed clear fluorescent cell imaging. Thus, the prepared novel FA:Yb3+/Ho3+ upconversion fluorescent crystals have potential applications in the biomedical field. PMID:24658285

  3. Investigation on the structure and upconversion fluorescence of Yb³⁺/Ho³⁺ co-doped fluorapatite crystals for potential biomedical applications.

    PubMed

    Li, Xiyu; Zhu, Jingxian; Man, Zhentao; Ao, Yingfang; Chen, Haifeng

    2014-01-01

    Rare-earth Yb(3+) and Ho(3+) co-doped fluorapatite (FA:Yb(3+)/Ho(3+)) crystals were prepared by hydrothermal synthesis, and their structure, upconversion properties, cell proliferation and imaging were investigated. The synthesized crystals, with a size of 16 by 286 nm, have a hexagonal crystal structure of classic FA and a Ca/Yb/Ho molar ratio of 100/16/2.1. Several reasonable Yb(3+)/Ho(3+) -embedding lattice models along the fluorine channel of the FA crystal cell are proposed for the first time, such as models for (Ca7YbHo©)(PO4)6F2 and (Ca6YbHoNa2)(PO4)6F2. The activated FA:Yb(3+)/Ho(3+) crystals were found to exhibit distinct upconversion fluorescence. The 543- and 654-nm signals in the emission spectra could be assigned, respectively, to the (5)F4 ((5)S2) - (5)I8 and (5)F5 - (5)I8 transitions of holmium via 980-nm near-infrared excitation and the energy transfer of ytterbium. After the surfaces were grafted with hydrophilic dextran, the crystals displayed clear fluorescent cell imaging. Thus, the prepared novel FA:Yb(3+)/Ho(3+) upconversion fluorescent crystals have potential applications in the biomedical field. PMID:24658285

  4. Investigation on the structure and upconversion fluorescence of Yb3+/Ho3+ co-doped fluorapatite crystals for potential biomedical applications

    NASA Astrophysics Data System (ADS)

    Li, Xiyu; Zhu, Jingxian; Man, Zhentao; Ao, Yingfang; Chen, Haifeng

    2014-03-01

    Rare-earth Yb3+ and Ho3+ co-doped fluorapatite (FA:Yb3+/Ho3+) crystals were prepared by hydrothermal synthesis, and their structure, upconversion properties, cell proliferation and imaging were investigated. The synthesized crystals, with a size of 16 by 286 nm, have a hexagonal crystal structure of classic FA and a Ca/Yb/Ho molar ratio of 100/16/2.1. Several reasonable Yb3+/Ho3+ -embedding lattice models along the fluorine channel of the FA crystal cell are proposed for the first time, such as models for (Ca7YbHo©)(PO4)6F2 and (Ca6YbHoNa2)(PO4)6F2. The activated FA:Yb3+/Ho3+ crystals were found to exhibit distinct upconversion fluorescence. The 543- and 654-nm signals in the emission spectra could be assigned, respectively, to the 5F4 (5S2) - 5I8 and 5F5 - 5I8 transitions of holmium via 980-nm near-infrared excitation and the energy transfer of ytterbium. After the surfaces were grafted with hydrophilic dextran, the crystals displayed clear fluorescent cell imaging. Thus, the prepared novel FA:Yb3+/Ho3+ upconversion fluorescent crystals have potential applications in the biomedical field.

  5. P8 deficiency increases cellular ROS and induces HO-1.

    PubMed

    Weis, Sebastian; Bielow, Tobias; Sommerer, Ines; Iovanna, Juan; Malicet, Cédric; Mössner, Joachim; Hoffmeister, Albrecht

    2015-01-01

    The gene p8 encodes for a small cytoprotective protein with no apparent enzymatic activity being proposed to act as co-transcription factor whose expression is increased during inflammation. Recent data from astrocytes demonstrates that p8 suppression leads to induction of heme oxygenase 1 (HO-1). Here, we assessed the cross-talk between p8 and HO-1 in mouse embryonic fibroblasts (MEF) observing an increased expression of HO-1 in p8-deficient (p8(-/-)) MEFs in non-treated and treated conditions. This effect was independent of the cell cycle. Our findings revealed that generation of reactive oxygen species (ROS) was higher in p8(-/-) MEFs. Mitochondria and NADPH oxidases were not the origin of ROS. This observation was not restricted to MEF as suppression of p8 gene transcription in MiaPaCa-2 cells also led to increased intracellular ROS. Additionally, p8 deficiency did not affect the Rac1 dependant NADPH oxidase complex. Our data shows that p8 deficiency increases ROS and subsequently the expression of anti-oxidative enzymes, such as HO-1, suggesting an involvement in the anti-oxidative defense. Moreover, we suggest that the severity of AP observed in p8(-/-) mice is induced by an impaired anti oxidative capacity of the pancreas, which is caused by increased generation of ROS. PMID:25475530

  6. {sup 163}Ho based experiments

    SciTech Connect

    Gastaldo, Loredana

    2015-07-15

    The analysis of the endpoint region of the calorimetrically measured {sup 163}Ho electron capture spectrum is a very promising way to determine the mass of the electron neutrino. The achievable sensitivity of {sup 163}Ho-based experiments and the experimental challenges will be presented. Three large collaborations aim at developing large scale experiments able to reach sub-eV sensitivity. Presently pilot experiments are performed to demonstrate the possibility to calorimetrically measure high precision and high statistics {sup 163}Ho spectra. The different approaches as well as the state of the art of the experimental efforts for the three collaborations will be discussed.

  7. 19. Southeast end room; view to southeast, 65mm lens plus ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    19. Southeast end room; view to southeast, 65mm lens plus electronic flash illumination. Note extent of failure; figure for scale. - Benicia Arsenal, Powder Magazine No. 5, Junction of Interstate Highways 680 & 780, Benicia, Solano County, CA

  8. 7. Detail, east portal of Tunnel 34/Snowshed 33, 135mm lens. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. Detail, east portal of Tunnel 34/Snowshed 33, 135mm lens. Tall signal mast necessary in order to be seen above winter snows. - Central Pacific Transcontinental Railroad, Tunnel No. 41, Milepost 193.3, Donner, Placer County, CA

  9. 18. Southeast end room; view to northeast, 65mm lens plus ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    18. Southeast end room; view to northeast, 65mm lens plus electronic flash illumination. Failed south wall at right. - Benicia Arsenal, Powder Magazine No. 5, Junction of Interstate Highways 680 & 780, Benicia, Solano County, CA

  10. 17. Oblique view, typical room; view to south, 65mm lens ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    17. Oblique view, typical room; view to south, 65mm lens plus electronic flash illumination. - Benicia Arsenal, Powder Magazine No. 5, Junction of Interstate Highways 680 & 780, Benicia, Solano County, CA

  11. 16. Oblique view, typical room; view to north, 65mm lens ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    16. Oblique view, typical room; view to north, 65mm lens plus electronic flash illumination. - Benicia Arsenal, Powder Magazine No. 5, Junction of Interstate Highways 680 & 780, Benicia, Solano County, CA

  12. Compact Ho:YLF Laser

    NASA Technical Reports Server (NTRS)

    Hemmati, H.

    1988-01-01

    Longitudinal pumping by laser diodes increases efficiency. Improved holmium:yttrium lithium fluoride laser radiates as much as 56 mW of power at wavelength of 2.1 micrometer. New Ho:YLF laser more compact and efficient than older, more powerful devices of this type. Compact, efficient Ho:YLF laser based on recent successes in use of diode lasers to pump other types of solid-state lasers.

  13. Credit USAF. Original housed in the Photograph Files, AFFTC/HO, Edwards ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Credit USAF. Original housed in the Photograph Files, AFFTC/HO, Edwards AFB, California. View of Motor Repair Shop (originally T-16), probably shortly after completion in 1943 - Edwards Air Force Base, North Base, Motor Repair Shop T-16, Third & C Streets, Boron, Kern County, CA

  14. 2. Credit USAF, 1943. Original housed in the AFFTC/HO, Edwards ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. Credit USAF, 1943. Original housed in the AFFTC/HO, Edwards AFB, California. View looks north northwest at south and east facades of hangar as it nears completion. - Edwards Air Force Base, North Base, Hangar No. 1, First & B Streets, Boron, Kern County, CA

  15. 5. Credit USAF, ca. 1942. Original housed in the Photograph ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. Credit USAF, ca. 1942. Original housed in the Photograph Files, AFFTC/HO, Edwards AFB, California. View of Bell Aircraft XP-59A Airacomet in flight. This was the United States military's first jet propelled aircraft which was extensively flight tested in secrecy at the Muroc Flight Test Base (North Base). - Edwards Air Force Base, North Base, North Base Road, Boron, Kern County, CA

  16. 9. Credit USAF, ca. 1955. Original housed in the Photograph ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. Credit USAF, ca. 1955. Original housed in the Photograph Files, AFFTC/HO, Edwards AFB, California. View of Lockheed XVF-1 Pogo, an experimental vertical take-off and landing aircraft at North Base. Photograph was taken on the apron between buildings 4401 and 4402, looking north northeast towards back of Building 4402 and officers' quarters (T-15) beyond. - Edwards Air Force Base, North Base, North Base Road, Boron, Kern County, CA

  17. Topics in Ho Morphophonology and Morphosyntax

    ERIC Educational Resources Information Center

    Pucilowski, Anna

    2013-01-01

    Ho, an under-documented North Munda language of India, is known for its complex verb forms. This dissertation focuses on analysis of several features of those complex verbs, using data from original fieldwork undertaken by the author. By way of background, an analysis of the phonetics, phonology and morphophonology of Ho is first presented. Ho has…

  18. Modification of Caffeic Acid with Pyrrolidine Enhances Antioxidant Ability by Activating AKT/HO-1 Pathway in Heart.

    PubMed

    Ku, Hui-Chun; Lee, Shih-Yi; Yang, Kai-Chien; Kuo, Yueh-Hsiung; Su, Ming-Jai

    2016-01-01

    Overproduction of free radicals during ischemia/reperfusion (I/R) injury leads to an interest in using antioxidant therapy. Activating an endogenous antioxidant signaling pathway is more important due to the fact that the free radical scavenging behavior in vitro does not always correlate with a cytoprotection effect in vivo. Caffeic acid (CA), an antioxidant, is a major phenolic constituent in nature. Pyrrolidinyl caffeamide (PLCA), a derivative of CA, was compared with CA for their antioxidant and cytoprotective effects. Our results indicate that CA and PLCA exert the same ability to scavenge DPPH in vitro. In response to myocardial I/R stress, PLCA was shown to attenuate lipid peroxydation and troponin release more than CA. These responses were accompanied with a prominent elevation in AKT and HO-1 expression and a preservation of mnSOD expression and catalase activity. PLCA also improved cell viability and alleviated the intracellular ROS level more than CA in cardiomyocytes exposed to H2O2. When inhibiting the AKT or HO-1 pathways, PLCA lost its ability to recover mnSOD expression and catalase activity to counteract with oxidative stress, suggesting AKT/HO-1 pathway activation by PLCA plays an important role. In addition, inhibition of AKT signaling further abolished HO-1 activity, while inhibition of HO-1 signaling attenuated AKT expression, indicating cross-talk between the AKT and HO-1 pathways. These protective effects may contribute to the cardiac function improvement by PLCA. These findings provide new insight into therapeutic approaches using a modified natural compound against oxidative stress from myocardial injuries. PMID:26845693

  19. Modification of Caffeic Acid with Pyrrolidine Enhances Antioxidant Ability by Activating AKT/HO-1 Pathway in Heart

    PubMed Central

    Ku, Hui-Chun; Lee, Shih-Yi; Yang, Kai-Chien; Kuo, Yueh-Hsiung; Su, Ming-Jai

    2016-01-01

    Overproduction of free radicals during ischemia/reperfusion (I/R) injury leads to an interest in using antioxidant therapy. Activating an endogenous antioxidant signaling pathway is more important due to the fact that the free radical scavenging behavior in vitro does not always correlate with a cytoprotection effect in vivo. Caffeic acid (CA), an antioxidant, is a major phenolic constituent in nature. Pyrrolidinyl caffeamide (PLCA), a derivative of CA, was compared with CA for their antioxidant and cytoprotective effects. Our results indicate that CA and PLCA exert the same ability to scavenge DPPH in vitro. In response to myocardial I/R stress, PLCA was shown to attenuate lipid peroxydation and troponin release more than CA. These responses were accompanied with a prominent elevation in AKT and HO-1 expression and a preservation of mnSOD expression and catalase activity. PLCA also improved cell viability and alleviated the intracellular ROS level more than CA in cardiomyocytes exposed to H2O2. When inhibiting the AKT or HO-1 pathways, PLCA lost its ability to recover mnSOD expression and catalase activity to counteract with oxidative stress, suggesting AKT/HO-1 pathway activation by PLCA plays an important role. In addition, inhibition of AKT signaling further abolished HO-1 activity, while inhibition of HO-1 signaling attenuated AKT expression, indicating cross-talk between the AKT and HO-1 pathways. These protective effects may contribute to the cardiac function improvement by PLCA. These findings provide new insight into therapeutic approaches using a modified natural compound against oxidative stress from myocardial injuries. PMID:26845693

  20. Application of MM wave therapy in radiology

    SciTech Connect

    Avakian, R.S.; Gasparyan, L.V.

    1995-12-31

    The authors studied the effects of MM wave electromagnetic radiation influence on patients, affected by X-ray radiation during the reparation works after Chernobyl nuclear power plant exposure. They compared results of treatment of two groups of patients: (1) control group patients received only basis therapy; (2) testing group, 10 patients received basis therapy and MM wave influence. The authors used the wide band noise generator `Artsakh - 2` for local irradiation on the acupuncture points. Their data proved that low intensity MM waves have immunocorrective, antioxidant effects, and MM wave therapy is a perspective method for treatment of patients with radiological pathology.

  1. Effects of Mg2+ on Ca2+ waves and Ca2+ transients of rat ventricular myocytes.

    PubMed

    Terada, H; Hayashi, H; Noda, N; Satoh, H; Katoh, H; Yamazaki, N

    1996-03-01

    It has been shown that the occurrence of the transient inward current, which is responsible for triggered activity, was often associated with propagating regions of increased intracellular Ca2+ concentration ([Ca2+]i), i.e., the "Ca2+ wave." To investigate the mechanism of antiarrhythmic action of Mg2+, we have studied effects of high concentrations of Mg2+ on Ca2+ waves in isolated rat ventricular myocytes. [Ca2+]i was estimated using the Ca(2+)-indicating probe indo 1. Ca2+ waves in myocytes, stimulated at 0.2 Hz, were induced by perfusion of isoproterenol (10(-7) M). High Mg2+ concentration suppressed Ca2+ waves in a concentration-dependent manner (36% at 4 mM, 70% at 8 mM, and 82% at 12 mM). The Ca2+ channel blocker verapamil also suppressed Ca2+ waves in a similar way. In contrast with marked depression of Ca2+ transients by verapamil, Ca2+ transients were not affected by high Mg2+ concentration (8 mM). High Mg2+ concentration also reduced frequencies of Ca2+ waves in the absence of electrical stimulation, whereas verapamil failed to reduce frequencies of Ca2+ waves. Reduction in frequency of Ca2+ waves by high Mg2+ concentration was associated with slowing of propagation velocity of Ca2+ waves. To examine whether suppressive effects of high Mg2+ concentration on Ca2+ waves were related to an increase in intracellular Mg2+ concentration ([Mg2+]i), the effect of high-Mg2+ solution on [Mg2+]i was examined in myocytes loaded with mag-fura 2. An increase in extracellular Mg2+ concentration from 1 to 12 mM increased [Mg2+]i from 1.06 +/- 0.16 to 1.87 +/- 0.22 mM (P < 0.01) in 30 min. To examine the effect of high Mg2+ concentration on amount of releasable Ca2+ in the sarcoplasmic reticulum, the effect of high Mg2+ concentration on the Ca2+ transient induced by a rapid application of caffeine was examined. High-Mg2+ solution increased the peak of the caffeine-induced Ca2+ transient. These results suggest that the inhibitory effect of Mg2+ on Ca2+ waves was not due

  2. 2-3 μm emission and fluorescent decaying behavior in Ho3+-doped tellurium germanate glass

    NASA Astrophysics Data System (ADS)

    Gao, Song; Liu, Xueqiang; Kang, Shuai; Liao, Meisong; Hu, Lili

    2016-03-01

    In this work, we report the 2.05 μm emission and ∼3 μm broadband spectra of Ho2O3-doped 33GeO2-30TeO2-27PbO-10CaO (in mol%) glass under 640 nm laser excitation. Clear emission spectra due to the 5I7-5I8 transition and the 5I6-5I7 transition in Ho3+ are observed. The 2.05 μm emission intensity and the full width at half maximum (FWHM) of the ∼3 μm broadband depend on the Ho concentration. The peak stimulated emission cross-section of Ho3+ is 6.57 × 10-21 cm2 at 2.05 μm, as calculated by the McCumber theory. The emission spectra are recorded and the maximum emission intensity at 2.05 μm is obtained at a doping level of 0.5 mol% Ho2O3 in the glass. A broad and flat emission band from 2700 nm to 3050 nm is observed in 2 mol% Ho2O3-doped tellurium germanate glass. The lifetime of the 5I7 state decreases with the increase in Ho3+ concentration due to non-radiative relaxation processes. An energy transfer coefficient of 271.88 mol-1 s-1 is obtained.

  3. Effects of Na+ and Ca2+ gradients on intracellular free Ca2+ in voltage-clamped Aplysia neurons.

    PubMed

    Levy, S; Tillotson, D

    1988-12-01

    Selected neurons of the abdominal ganglion of Aplysia californica were voltage-clamped and intracellular free Ca [( Ca2+]i) and Na [( Na+]i) concentrations were monitored with ion selective microelectrodes. Reducing [Na+]o from 500 mM (normal seawater, NSW) to 5 mM resulted in a decrease of the potential measured by the Ca electrode (VCa). Increasing [Ca2+]o from 10 to 50 mM increased [Ca2+]i two-fold, keeping [Ca2+]o at 50 mM and decreasing [Na+]o to 5 mM still led to a decrease in VCa. With 100 mM [Ca2+]o, which also increased [Ca2+]i, decreasing [Na+]o increased VCa in two of the eight cells tested. This indicates that in normal or moderately high resting [Ca2+]i, Ca2+ extrusion by Na/Ca exchange (forward mode) is not essential for [Ca2+]i buffering. [Na+]i was 12.9 +/- 3.6 mM (S.E.M., n = 7) in NSW; reducing [Na+]o to 5 mM decreased [Na+]i to 2.0 +/- 1.1 mM (S.E.M.). Keeping [Na+]o at 5 mM and increasing [Ca2+]o from 10 to 20 mM further decreased [Na+]i to about 1.0 mM, evidence of Na/Ca exchange operating in the reverse mode. Attempts to increase [Ca2+]i by bath application of the Ca ionophores A23187, X537A, ionomycin or ETH 1001 resulted in no measurable change of the resting [Ca2+]i. Application of Ouabain caused an apparent increase in [Ca2+]i in two of the six cells tested. In cells injected with the metallochromic indicator arsenazo III (AIII), the rate of the falling phase of the AIII absorbance increase, following a voltage-clamp pulse, was significantly slower in 5 mM [Na+]o. This indicates that in its forward mode Na-Ca exchange is active in clearing large submembrane increases in [Ca2+]i. PMID:3208137

  4. Multimedia contents production system (MM-CPS)

    NASA Astrophysics Data System (ADS)

    Roser, Miguel; Villegas, Paulo; Simon, Maria; Hernandez-Gil, J. F.; Aguado, Isidro

    1996-01-01

    A present characterized by deep worldwide changes, and a future where social relations and behaviors are going to undergo a substantial change need new telecommunications services in order to allow people to get closer, facilitate their daily tasks and place at their disposal multimedia information to be accessed anywhere and at any time. These new services are very dependent on the contents to be included in the applications. The purpose of this paper is to describe an universal MM contents production system (MM-CPS), which allows the generation of coded data files suitable to be included in MM-servers.

  5. 60W Ho:YLF oscillator-amplifier system

    NASA Astrophysics Data System (ADS)

    Koen, Wayne; Jacobs, Cobus; Wu, Lorinda; Strauss, Hencharl J.

    2015-02-01

    We developed a compact Ho:YLF oscillator-amplifier system end-pumped by two 54 W unpolarised Tm:fibre lasers, and produced 60.2 W of output power at 2064 nm. The oscillator consisted of a flat input coupler mirror, a 50 mm long 0.5 % doped Ho:YLF crystal rod, a 45 degree folding mirror, an AOM, and a concave output coupler mirror. The oscillator operated vertically polarised on the holmium crystal's σ-polarisation, ensuring good beam quality from the weak thermal lens. The concave output coupler had a radius of 300 mm and a reflectivity of 82 % at 2064 nm. The oscillator gave a maximum output of 24 W with an M2 of 1.06. The single-pass amplifier consisted of two 40 mm long, 0.5 % doped, Ho:YLF crystal rods and four folding mirrors. While the seed laser was pumped by a single fibre laser, the amplifier utilized the transmitted pump light from the seed laser in addition to the second fibre laser. With the first crystal amplifying on the σ-polarisation and the second crystal on the π-polarisation, the amplifier delivered 60.2 W with an M2 of 1.09, representing a gain of 2.5 while achieving an optical-to-optical efficiency of 55.5 %. When Q-switched with the AOM, the system delivered pulse lengths of between 43 and 113 ns at repetition rates from 15 to 40 kHz.

  6. Delayed cutaneous wound closure in HO-2 deficient mice despite normal HO-1 expression

    PubMed Central

    Lundvig, Ditte M S; Scharstuhl, Alwin; Cremers, Niels A J; Pennings, Sebastiaan W C; te Paske, Jeroen; van Rheden, René; van Run-van Breda, Coby; Regan, Raymond F; Russel, Frans G M; Carels, Carine E; Maltha, Jaap C; Wagener, Frank A D T G

    2014-01-01

    Impaired wound healing can lead to scarring, and aesthetical and functional problems. The cytoprotective haem oxygenase (HO) enzymes degrade haem into iron, biliverdin and carbon monoxide. HO-1 deficient mice suffer from chronic inflammatory stress and delayed cutaneous wound healing, while corneal wound healing in HO-2 deficient mice is impaired with exorbitant inflammation and absence of HO-1 expression. This study addresses the role of HO-2 in cutaneous excisional wound healing using HO-2 knockout (KO) mice. Here, we show that HO-2 deficiency also delays cutaneous wound closure compared to WT controls. In addition, we detected reduced collagen deposition and vessel density in the wounds of HO-2 KO mice compared to WT controls. Surprisingly, wound closure in HO-2 KO mice was accompanied by an inflammatory response comparable to WT mice. HO-1 induction in HO-2 deficient skin was also similar to WT controls and may explain this protection against exaggerated cutaneous inflammation but not the delayed wound closure. Proliferation and myofibroblast differentiation were similar in both two genotypes. Next, we screened for candidate genes to explain the observed delayed wound closure, and detected delayed gene and protein expression profiles of the chemokine (C-X-C) ligand-11 (CXCL-11) in wounds of HO-2 KO mice. Abnormal regulation of CXCL-11 has been linked to delayed wound healing and disturbed angiogenesis. However, whether aberrant CXCL-11 expression in HO-2 KO mice is caused by or is causing delayed wound healing needs to be further investigated. PMID:25224969

  7. A many-body model to study proteins. I. Applications to MLnm+ complexes, Mm+=Li+, Na+, K+, Mg2+, Ca2+, and Zn2+, L=H2O, CH3OH, HCONH2, n=1-6, and to small hydrogen bonded systems

    NASA Astrophysics Data System (ADS)

    Masella, Michel; Cuniasse, Philippe

    2003-07-01

    A new model to study proteinic systems including a many-body polarization and a hydrogen bond energy contribution is presented. This model represents an extension of an earlier water many-body model [M. Masella and J.-P. Flament, J. Chem. Phys. 107 9105 (1997)]. As in this earlier model, the new model is developed to reproduce quantum computations on small molecular aggregates, and, in this first paper, we focus our efforts in developing an accurate potential to describe interactions among all nonbonded atoms occurring in proteins, and among those atoms and six cations of biological interest: Li+, Na+, K+, Mg2+, Ca2+, and Zn2+. Intramolecular degrees of freedom are described as in classical two-body force fields. In the present paper, the new model is applied to investigate the properties of small ion-neutral [M,Ln]m+ complexes and of small hydrogen-bonded systems. The results showed that this model is able to reproduce most of the theoretical quantum predictions and experimental data published until now regarding those systems.

  8. MM Algorithms for Geometric and Signomial Programming.

    PubMed

    Lange, Kenneth; Zhou, Hua

    2014-02-01

    This paper derives new algorithms for signomial programming, a generalization of geometric programming. The algorithms are based on a generic principle for optimization called the MM algorithm. In this setting, one can apply the geometric-arithmetic mean inequality and a supporting hyperplane inequality to create a surrogate function with parameters separated. Thus, unconstrained signomial programming reduces to a sequence of one-dimensional minimization problems. Simple examples demonstrate that the MM algorithm derived can converge to a boundary point or to one point of a continuum of minimum points. Conditions under which the minimum point is unique or occurs in the interior of parameter space are proved for geometric programming. Convergence to an interior point occurs at a linear rate. Finally, the MM framework easily accommodates equality and inequality constraints of signomial type. For the most important special case, constrained quadratic programming, the MM algorithm involves very simple updates. PMID:24634545

  9. MM Algorithms for Geometric and Signomial Programming

    PubMed Central

    Lange, Kenneth; Zhou, Hua

    2013-01-01

    This paper derives new algorithms for signomial programming, a generalization of geometric programming. The algorithms are based on a generic principle for optimization called the MM algorithm. In this setting, one can apply the geometric-arithmetic mean inequality and a supporting hyperplane inequality to create a surrogate function with parameters separated. Thus, unconstrained signomial programming reduces to a sequence of one-dimensional minimization problems. Simple examples demonstrate that the MM algorithm derived can converge to a boundary point or to one point of a continuum of minimum points. Conditions under which the minimum point is unique or occurs in the interior of parameter space are proved for geometric programming. Convergence to an interior point occurs at a linear rate. Finally, the MM framework easily accommodates equality and inequality constraints of signomial type. For the most important special case, constrained quadratic programming, the MM algorithm involves very simple updates. PMID:24634545

  10. T-Type Ca2+ Channel Regulation by CO: A Mechanism for Control of Cell Proliferation.

    PubMed

    Duckles, Hayley; Al-Owais, Moza M; Elies, Jacobo; Johnson, Emily; Boycott, Hannah E; Dallas, Mark L; Porter, Karen E; Boyle, John P; Scragg, Jason L; Peers, Chris

    2015-01-01

    T-type Ca(2+) channels regulate proliferation in a number of tissue types, including vascular smooth muscle and various cancers. In such tissues, up-regulation of the inducible enzyme heme oxygenase-1 (HO-1) is often observed, and hypoxia is a key factor in its induction. HO-1 degrades heme to generate carbon monoxide (CO) along with Fe(2+) and biliverdin. Since CO is increasingly recognized as a regulator of ion channels (Peers et al. 2015), we have explored the possibility that it may regulate proliferation via modulation of T-type Ca(2+) channels.Whole-cell patch-clamp recordings revealed that CO (applied as the dissolved gas or via CORM donors) inhibited all 3 isoforms of T-type Ca(2+) channels (Cav3.1-3.3) when expressed in HEK293 cells with similar IC(50) values, and induction of HO-1 expression also suppressed T-type currents (Boycott et al. 2013). CO/HO-1 induction also suppressed the elevated basal [Ca(2+) ](i) in cells expressing these channels and reduced their proliferative rate to levels seen in non-transfected control cells (Duckles et al. 2015).Proliferation of vascular smooth muscle cells (both A7r5 and human saphenous vein cells) was also suppressed either by T-type Ca(2+) channel inhibitors (mibefradil and NNC 55-0396), HO-1 induction or application of CO. Effects of these blockers and CO were non additive. Although L-type Ca(2+) channels were also sensitive to CO (Scragg et al. 2008), they did not influence proliferation. Our data suggest that HO-1 acts to control proliferation via CO modulation of T-type Ca(2+) channels. PMID:26303493

  11. QM/MM Calculations on Proteins.

    PubMed

    Ryde, U

    2016-01-01

    In this chapter, I discuss combined quantum mechanics (QM) and molecular mechanics (MM; QM/MM) calculations for proteins. In QM/MM, a small but interesting part of the protein is treated by accurate QM methods, whereas the remainder is treated by faster MM methods. The prime problems with QM/MM calculations are bonds between the QM and MM systems, the selection of the QM system, and the local-minima problem. The two first problems can be solved by the big-QM approach, including in the QM calculation all groups within 4.5-6Å of the active site and all buried charges in the protein. The third problem can be solved by calculating free energies. It is important to study QM/MM energy components to ensure that the results are stable and reliable. They can also be used to understand the reaction and the effect of the surroundings, eg, by dividing the catalytic effect into bonded, van der Waals, electrostatic, and geometric components and to deduce which parts of the protein contribute most to the catalysis. It should be ensured that the QM calculations are reliable and converged by extending the basis set to quadruple-zeta quality, including a proper treatment of dispersion, as well as years experience and method development calculations with both pure and hybrid density functional theory methods. If the latter give differing results, calibration with high-level QM methods is needed. Reactions that change the net charge should be avoided. QM/MM calculations can be combined with experimental methods. PMID:27498637

  12. Dark filaments observed at 8.3mm and 3.1mm wavelength

    NASA Technical Reports Server (NTRS)

    Hiel, E.; Ishiguro, M.; Kosugi, T.; Shibasaki, K.

    1986-01-01

    Mapping of the sun was made at 3.1mm (98 GHz) and 8.3mm (36 GHz) wavelengths with a 45m dish radio telescope at the Nobeyama Cosmic Radio Observatory. The depressions associated with large H alpha filaments are derived to be -0.2 at 8.3mm and -0.05 at 3.1mm, which are darker than the values inferred by Raoult et al. (1979)

  13. 8. Credit USAF, ca. 1952. Original housed in the Photograph ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. Credit USAF, ca. 1952. Original housed in the Photograph Files, AFFTC/HO, Edwards AFB, California. Oblique low-level aerial view of North Base looking northeast. Based on positions and types of aircraft and automobiles, this photo taken same day as HAER photo CA-170-7. Most temporary structures in this view have been demolished with the exception of the hangars. The concrete foundations remain of many structures, while no trace was found of others. - Edwards Air Force Base, North Base, North Base Road, Boron, Kern County, CA

  14. 40 CFR Table 1 to Subpart Mm of... - General Provisions Applicability to Subpart MM

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ....860. 63.1(b)(2) Title V operating permit—see 40 CFR part 70 Yes All major affected sources are... Subpart MM 1 Table 1 to Subpart MM of Part 63 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Combustion Sources at Kraft, Soda, Sulfite, and Stand-Alone Semichemical Pulp Mills Pt. 63, Subpt. MM,...

  15. 40 CFR Table 1 to Subpart Mm of... - General Provisions Applicability to Subpart MM

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ....860. 63.1(b)(2) Title V operating permit—see 40 CFR part 70 Yes All major affected sources are... Subpart MM 1 Table 1 to Subpart MM of Part 63 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Combustion Sources at Kraft, Soda, Sulfite, and Stand-Alone Semichemical Pulp Mills Pt. 63, Subpt. MM,...

  16. 40 CFR Table 1 to Subpart Mm of... - General Provisions Applicability to Subpart MM

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ....860. 63.1(b)(2) Title V operating permit—see 40 CFR part 70 Yes All major affected sources are... Subpart MM 1 Table 1 to Subpart MM of Part 63 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Combustion Sources at Kraft, Soda, Sulfite, and Stand-Alone Semichemical Pulp Mills Pt. 63, Subpt. MM,...

  17. 40 CFR Table 1 to Subpart Mm of... - General Provisions Applicability to Subpart MM

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ....860. 63.1(b)(2) Title V operating permit—see 40 CFR part 70 Yes All major affected sources are... Subpart MM 1 Table 1 to Subpart MM of Part 63 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Combustion Sources at Kraft, Soda, Sulfite, and Stand-Alone Semichemical Pulp Mills Pt. 63, Subpt. MM,...

  18. 40 CFR Table 1 to Subpart Mm of... - General Provisions Applicability to Subpart MM

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ....860. 63.1(b)(2) Title V operating permit—see 40 CFR part 70 Yes All major affected sources are... Subpart MM 1 Table 1 to Subpart MM of Part 63 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Combustion Sources at Kraft, Soda, Sulfite, and Stand-Alone Semichemical Pulp Mills Pt. 63, Subpt. MM,...

  19. Near infrared luminescence in Yb3+/Ho3+: co-doped germanate glass

    NASA Astrophysics Data System (ADS)

    Kochanowicz, Marcin; Żmojda, Jacek; Miluski, Piotr; Ragin, Tomasz; Jeleń, Piotr; Sitarz, Maciej; Dorosz, Dominik

    2015-12-01

    The near-infrared emission of low phonon (805 cm-1) germanate glasses from GeO2-Ga2O3-BaO system co-doped with 0.7Yb2O3/(0.07-0.7)Ho2O3 ions has been investigated. Luminescence at 2.1 μm corresponding to 5I7 → 5I8 transition in holmium was obtained by energy transfer between Yb3+ and Ho3+ ions. The optimization of the activator content and the concentration ratio were conducted with the purpose of maximizing the efficiency of energy transfer and as a consequence luminescence intensity at 2mm. The highest value of the luminescence intensity was obtained in glass codoped with 0.7Yb2O3/0.15 Ho2O3.

  20. In vitro investigation on Ho:YAG laser-assisted bone ablation underwater.

    PubMed

    Zhang, Xianzeng; Chen, Chuanguo; Chen, Faner; Zhan, Zhenlin; Xie, Shusen; Ye, Qing

    2016-07-01

    Liquid-assisted hard tissue ablation by infrared lasers has extensive clinical application. However, detailed studies are still needed to explore the underlying mechanism. In the present study, the dynamic process of bubble evolution induced by Ho:YAG laser under water without and with bone tissue at different thickness layer were studied, as well as its effects on hard tissue ablation. The results showed that the Ho:YAG laser was capable of ablating hard bone tissue effectively in underwater conditions. The penetration of Ho:YAG laser can be significantly increased up to about 4 mm with the assistance of bubble. The hydrokinetic forces associated with the bubble not only contributed to reducing the thermal injury to peripheral tissue, but also enhanced the ablation efficiency and improve the ablation crater morphology. The data also presented some clues to optimal selection of irradiation parameters and provided additional knowledge of the bubble-assisted hard tissue ablation mechanism. PMID:27056700

  1. Ferroelectricity and competing interactions in Ho-deficient non-stoichiometric orthorhombic HoMnO{sub 3}

    SciTech Connect

    Wang, J. X.; Yan, Z. B.; Xie, Y. L.; Zhou, X. H.; Liu, J.-M.

    2015-05-07

    We investigate the consequences of the Ho-deficient non-stoichiometry in orthorhombic HoMnO{sub 3} in terms of microscopic mechanisms for ferroelectricity modulation. It is suggested that the Ho-deficiency (then Mn excess) results in Ho-vacancies and then Mn occupation of the Ho-site with increasing non-stoichiometry. The Ho-deficiency enhances the Mn-Mn symmetric exchange striction by suppressing the independent Ho-Ho interaction, and thus benefits to the induced Ho spin ordering against the independent Ho spin ordering. The symmetric Ho-Mn exchange striction is thus enhanced by this induced Ho spin ordering, leading to remarkably enhanced ferroelectric polarization as observed. This work presents an alternative scheme to modulate the multiferroicity in rare-earth manganites of strong 4f-3d coupling.

  2. Tm:YLF Pumped Ho:YAG and Ho:LuAG Lasers

    NASA Technical Reports Server (NTRS)

    Barnes, Norman P.; Reichle, Donald J.; Walsh, Brian M.; Axenson, Theresa J.

    2004-01-01

    Room temperature Ho:YAG and Ho:LuAG lasers pumped by a Tm:YLF laser demonstrated a 3.4 mJ threshold and 0.41 slope efficiency, incident optical to laser output energy. Results for numerous rod lengths, Ho concentrations, and output mirror reflectivities are presented.

  3. Laparoscopic cholecystectomy using 2-mm instruments.

    PubMed

    Uranüs, S; Peng, Z; Kronberger, L; Pfeifer, J; Salehi, B

    1998-10-01

    Today, laparoscopic cholecystectomy is the method of choice for treatment of symptomatic gallbladder disorders. It minimizes effects of the operation that are independent of the gallbladder, such as trauma to the abdominal wall and other soft tissue. The surgical wounds were even smaller when 2-mm trocars were used. Laparoscopic cholecystectomy using 2-mm instruments was performed in a consecutive series of 14 patients with symptomatic gallstones. The procedure was completed in 12 cases, with conversion to open surgery in two cases. Intraoperative cholangiography was always performed. The postoperative course was always uneventful. The cosmetic effect was highly satisfactory. The procedure using 2-mm instruments could be indicated in selected patients with uncomplicated gallstone disease. PMID:9820716

  4. Microeconomics of 300-mm process module control

    NASA Astrophysics Data System (ADS)

    Monahan, Kevin M.; Chatterjee, Arun K.; Falessi, Georges; Levy, Ady; Stoller, Meryl D.

    2001-08-01

    Simple microeconomic models that directly link metrology, yield, and profitability are rare or non-existent. In this work, we validate and apply such a model. Using a small number of input parameters, we explain current yield management practices in 200 mm factories. The model is then used to extrapolate requirements for 300 mm factories, including the impact of simultaneous technology transitions to 130nm lithography and integrated metrology. To support our conclusions, we use examples relevant to factory-wide photo module control.

  5. Investigation of loss processes of Tm and Tm,Ho in YAG

    NASA Technical Reports Server (NTRS)

    Armagan, G.; Buoncristiani, A. M.; Bair, C. H.; Inge, A. T.; Hess, R. V.

    1991-01-01

    The loss of excitation from various manifolds of Tm and Tm,Ho in YAG as a function of temperature and concentration is studied. Two probable loss mechanisms - a Tm up-conversion and a Ho up-conversion - are identified. A 785-nm CW diode laser with 400-nW peak power was focused to a small spot on the sample. The emission from the sample observed at 90 deg was monitored through a monochromator with slits open to 3 mm. Intensity of emission was measured by varying the power of the excitation source using a set of neutral density filters. Power is reported as the percentage of the peak power, and the intensity curves were normalized below 20 percent of transmission. The fact that there is emission above the pump energy indicates an up-conversion from excited manifolds. Nonlinear changes in the intensity of the emission from the Tm 3F4 manifold with the pump power reveals a loss of excitation from this manifold. The linear dependence of the 5I7 manifold emission with pump power at low Tm and high Ho concentrations and the gain of energy in the 5I6 manifold of Ho indicate that the 5I7 manifold loss is due to the coupling of Tm and Ho ions.

  6. Optimizing digital 8mm drive performance

    NASA Technical Reports Server (NTRS)

    Schadegg, Gerry

    1993-01-01

    The experience of attaching over 350,000 digital 8mm drives to 85-plus system platforms has uncovered many factors which can reduce cartridge capacity or drive throughput, reduce reliability, affect cartridge archivability and actually shorten drive life. Some are unique to an installation. Others result from how the system is set up to talk to the drive. Many stem from how applications use the drive, the work load that's present, the kind of media used and, very important, the kind of cleaning program in place. Digital 8mm drives record data at densities that rival those of disk technology. Even with technology this advanced, they are extremely robust and, given proper usage, care and media, should reward the user with a long productive life. The 8mm drive will give its best performance using high-quality 'data grade' media. Even though it costs more, good 'data grade' media can sustain the reliability and rigorous needs of a data storage environment and, with proper care, give users an archival life of 30 years or more. Various factors, taken individually, may not necessarily produce performance or reliability problems. Taken in combination, their effects can compound, resulting in rapid reductions in a drive's serviceable life, cartridge capacity, or drive performance. The key to managing media is determining the importance one places upon their recorded data and, subsequently, setting media usage guidelines that can deliver data reliability. Various options one can implement to optimize digital 8mm drive performance are explored.

  7. MM-122: High speed civil transport

    NASA Technical Reports Server (NTRS)

    Demarest, Bill; Anders, Kurt; Manchec, John; Yang, Eric; Overgaard, Dan; Kalkwarf, Mike

    1992-01-01

    The rapidly expanding Pacific Rim market along with other growing markets indicates that the future market potential for a high speed civil transport is great indeed. The MM-122 is the answer to the international market desire for a state of the art, long range, high speed civil transport. It will carry 250 passengers a distance of 5200 nm at over twice the speed of sound. The MM-122 is designed to incorporate the latest technologies in the areas of control systems, propulsions, aerodynamics, and materials. The MM-122 will accomplish these goals using the following design parameters. First, a double delta wing planform with highly swept canards and an appropriately area ruled fuselage will be incorporated to accomplish desired aerodynamic characteristics. Propulsion will be provided by four low bypass variable cycle turbofan engines. A quad-redundant fly-by-wire flight control system will be incorporated to provide appropriate static stability and level 1 handling qualities. Finally, the latest in conventional metallic and modern composite materials will be used to provide desired weight and performance characteristics. The MM-122 incorporates the latest in technology and cost minimization techniques to provide a viable solution to this future market potential.

  8. Mm-wave power meter mount

    NASA Technical Reports Server (NTRS)

    Mullen, D. L.; Oltmans, D. A.; Stelzried, C. T.

    1968-01-01

    E-band thermistor mount and a technique for adjusting a temperature compensating thermistor to provide an electrically balanced bridge are used for measuring RF power in the mm-wavelength. The mount is relatively insensitive to temperature effects that cause measurement errors in single ended circuits.

  9. CCM3 to MM5 Data Conversion

    Energy Science and Technology Software Center (ESTSC)

    2007-03-02

    The accompanying script (which uses the NCAR Command Language) ready output from the Community Climate Model Code, version 3 (CCM3) and converts it to input format for the Mesoscale Model, version 5 (MM5) code. The script utilizes a Fortran binary write routine.

  10. Shape coexistence in 153Ho

    NASA Astrophysics Data System (ADS)

    Pramanik, Dibyadyuti; Sarkar, S.; Saha Sarkar, M.; Bisoi, Abhijit; Ray, Sudatta; Dasgupta, Shinjinee; Chakraborty, A.; Krishichayan, Kshetri, Ritesh; Ray, Indrani; Ganguly, S.; Pradhan, M. K.; Ray Basu, M.; Raut, R.; Ganguly, G.; Ghugre, S. S.; Sinha, A. K.; Basu, S. K.; Bhattacharya, S.; Mukherjee, A.; Banerjee, P.; Goswami, A.

    2016-08-01

    The high-spin states in 153Ho have been studied by the La57(20Ne139,6 n ) reaction at a projectile energy of 139 MeV at the Variable Energy Cyclotron Centre (VECC), Kolkata, India, utilizing an earlier campaign of the Indian National Gamma Array (INGA) setup. Data from γ -γ coincidence, directional correlation, and polarization measurements have been analyzed to assign and confirm the spins and parities of the levels. We have suggested a few additions and revisions of the reported level scheme of 153Ho. The RF-γ time difference spectra have been useful to confirm the half-life of an isomer in this nucleus. From the comparison of experimental and theoretical results, it is found that there are definite indications of shape coexistence in this nucleus. The experimental and calculated lifetimes of several isomers have been compared to follow the coexistence and evolution of shape with increasing spin.

  11. The role of luminal Ca2+ in the generation of Ca2+ waves in rat ventricular myocytes

    PubMed Central

    Lukyanenko, Valeriy; Subramanian, Saisunder; Györke, Inna; Wiesner, Theodore F; Györke, Sandor

    1999-01-01

    We used confocal Ca2+ imaging and fluo-3 to investigate the transition of localized Ca2+ releases induced by focal caffeine stimulation into propagating Ca2+ waves in isolated rat ventricular myocytes. Self-sustaining Ca2+ waves could be initiated when the cellular Ca2+ load was increased by elevating the extracellular [Ca2+] ([Ca2+]o) and they could also be initiated at normal Ca2+ loads when the sensitivity of the release sites to cytosolic Ca2+ was enhanced by low doses of caffeine. When we prevented the accumulation of extra Ca2+ in the luminal compartment of the sarcoplasmic reticulum (SR) with thapsigargin, focal caffeine pulses failed to trigger self-sustaining Ca2+ waves on elevation of [Ca2+]o. Inhibition of SR Ca2+ uptake by thapsigargin in cells already preloaded with Ca2+ above normal levels did not prevent local Ca2+ elevations from triggering propagating waves. Moreover, wave velocity increased by 20 %. Tetracaine (0·75 mM) caused transient complete inhibition of both local and propagating Ca2+ signals, followed by full recovery of the responses due to increased SR Ca2+ accumulation. Computer simulations using a numerical model with spatially distinct Ca2+ release sites suggested that increased amounts of releasable Ca2+ might not be sufficient to generate self-sustaining Ca2+ waves under conditions of Ca2+ overload unless the threshold of release site Ca2+ activation was set at relatively low levels (< 1·5 μM). We conclude that the potentiation of SR Ca2+ release channels by luminal Ca2+ is an important factor in Ca2+ wave generation. Wave propagation does not require the translocation of Ca2+ from the spreading wave front into the SR. Instead, it relies on luminal Ca2+ sensitizing Ca2+ release channels to cytosolic Ca2+. PMID:10373699

  12. A New Laboratory for MM-/Sub-MM-Wave Characterization of Cosmic Dust Analogs

    NASA Astrophysics Data System (ADS)

    Birsa, Samuel; Do, Huy; Williams, Frederick; Liu, Lunjun; Schonert, Ryan; Perera, Thushara

    2015-01-01

    Most studies conducted with observatories such as ALMA, SOFIA, PLANCK, and Herschel will benefit from knowledge of (1) the predominant cosmic dust species in various environments, in terms of composition and structure and (2) mm/sub-mm optical properties of cosmic dusts, including the temperature dependent-emissivity and spectral index. A new laboratory has been established for producing and characterizing (in the mm/sub-mm) various silicate/carbonaceous dust candidates. In particular, the optical measurement setup was custom designed, specifically for laboratory studies of dusts, using techniques borrowed from observational cosmology. It features novel designs for a compact Fourier Transform Spectrometer (FTS) and a cold sample holder/exchanger. Construction of this apparatus is now complete; we are currently testing the system. Here, we present the mm/sub-mm measurement scheme and highlight its innovative and aspects.

  13. Comparison between 28 mm and 32 mm ceramic-on-ceramic bearings in total hip replacement.

    PubMed

    Lee, Y K; Ha, Y C; Koo, K H

    2014-11-01

    Large femoral heads have become popular in total hip replacement (THR) as a method of reducing the risk of dislocation. However, if large heads are used in ceramic-on-ceramic THR, the liner must be thinner, which may increase the risk of fracture. To compare the rates of ceramic fracture and dislocation between 28 mm and 32 mm ceramic heads, 120 hips in 109 patients (51 men and 58 women, mean age 49.2 years) were randomised to THR with either a 28 mm or a 32 mm ceramic articulation. A total of 57/60 hips assigned to the 28 mm group and 55/60 hips assigned to the 32 mm group were followed for at least five years. No ceramic component fractures occured in any patient in either group. There was one dislocation in the 32 mm group and none in the 28 mm group (p = 0.464). No hip had detectable wear, focal osteolysis or prosthetic loosening. In our small study the 32 mm ceramic articulation appeared to be safe in terms of ceramic liner fracture. PMID:25371457

  14. Peroxynitric acid (HO2NO2) measurements during the UBWOS 2013 and 2014 studies using iodide ion chemical ionization mass spectrometry

    NASA Astrophysics Data System (ADS)

    Veres, P. R.; Roberts, J. M.; Wild, R. J.; Edwards, P. M.; Brown, S. S.; Bates, T. S.; Quinn, P. K.; Johnson, J. E.; Zamora, R. J.; de Gouw, J.

    2015-07-01

    In this paper laboratory work is documented establishing iodide ion chemical ionization mass spectrometry (I- CIMS) as a sensitive method for the unambiguous detection of peroxynitric acid (HO2NO2; PNA). A dynamic calibration source for HO2NO2, HO2, and HONO was developed and calibrated using a novel total NOy cavity ring-down spectroscopy (CaRDS) detector. Photochemical sources of these species were used for the calibration and validation of the I- CIMS instrument for detection of HO2NO2. Ambient observations of HO2NO2 using I- CIMS during the 2013 and 2014 Uintah Basin Wintertime Ozone Study (UBWOS) are presented. Strong inversions leading to a build-up of many primary and secondary pollutants as well as low temperatures drove daytime HO2NO2 as high as 1.5 ppbv during the 2013 study. A comparison of HO2NO2 observations to mixing ratios predicted using a chemical box model describing an ozone formation event observed during the 2013 wintertime shows agreement in the daily maxima HO2NO2 mixing ratio, but a differences of several hours in the timing of the observed maxima. Observations of vertical gradients suggest that the ground snow surface potentially serves as both a net sink and source of HO2NO2 depending on the time of day. Sensitivity tests using a chemical box model indicate that the lifetime of HO2NO2 with respect to deposition has a non-negligible impact on ozone production rates on the order of 10 %.

  15. AN ELISA ASSAY FOR HEME OXYGENASE (HO-1)

    EPA Science Inventory

    An ELISA assay for heme oxygenase (HO-l )

    Abstract

    A double antibody capture ELISA for the HO-l protein has been developed to separately quantitate HO-I protein. The use of 2.5% NP40 detergent greatly assists in freeing HO-l protein from membranes and/or other cel...

  16. Registration of "HoCP 00-950" Sugarcane

    Technology Transfer Automated Retrieval System (TEKTRAN)

    HoCP 00-950 sugarcane was selected from progeny of the cross HoCP 93-750 x HoCP 92-676 made at Canal Point, Florida. HoCP 00-950 was developed through cooperative research by the Agricultural Research Service of the United States Department of Agriculture, the Louisiana Agricultural Experiment Stati...

  17. Development of mini-tablets with 1mm and 2mm diameter.

    PubMed

    Tissen, Corinna; Woertz, Katharina; Breitkreutz, Joerg; Kleinebudde, Peter

    2011-09-15

    The feasibility of formulating mini-tablets with 1mm diameter on a rotary-die press in comparison to mini-tablets of 2mm was investigated. To gain insight into the production of 1mm mini-tablets, three model drugs of different compression characteristics were chosen, namely quinine hydrochloride, ibuprofen and spray-dried gentian extract. A high drug load in combination with robust and reproducible mechanical properties was requested. Depending on the individual drug substance, mini-tablets were produced by direct compression or after roll-compaction/dry granulation. The tensile strength, mass, and their variation coefficients were determined to assess the mechanical properties of the tablets. The content uniformity and the dissolution behavior of selected batches were analyzed. For the first time 1mm mini-tablets could be successfully produced by direct compression (90% quinine hydrochloride; 90% dried gentian extract) and after roll compaction (70% ibuprofen). Depending on the applied compression pressure, 1mm mini-tablets with quinine hydrochloride exhibited robust mechanical properties (e.g. median tensile strength of 2.02N/mm(2)) with equal or lower variance of distribution compared to the 2mm compacts. With respect to content uniformity of dosage forms, 1mm mini-tablets containing 80% quinine hydrochloride met the requirements of the European Pharmacopeia (AV=6.8). PMID:21726616

  18. Impact of Ho(3+)-doping on (13)C dynamic nuclear polarization using trityl OX063 free radical.

    PubMed

    Kiswandhi, Andhika; Niedbalski, Peter; Parish, Christopher; Kaur, Pavanjeet; Martins, André; Fidelino, Leila; Khemtong, Chalermchai; Song, Likai; Sherry, A Dean; Lumata, Lloyd

    2016-08-21

    We have investigated the effects of Ho-DOTA doping on the dynamic nuclear polarization (DNP) of [1-(13)C] sodium acetate using trityl OX063 free radical at 3.35 T and 1.2 K. Our results indicate that addition of 2 mM Ho-DOTA on 3 M [1-(13)C] sodium acetate sample in 1 : 1 v/v glycerol : water with 15 mM trityl OX063 improves the DNP-enhanced (13)C solid-state nuclear polarization by a factor of around 2.7-fold. Similar to the Gd(3+) doping effect on (13)C DNP, the locations of the positive and negative (13)C maximum polarization peaks in the (13)C microwave DNP sweep are shifted towards each other with the addition of Ho-DOTA on the DNP sample. W-band electron spin resonance (ESR) studies have revealed that while the shape and linewidth of the trityl OX063 ESR spectrum was not affected by Ho(3+)-doping, the electron spin-lattice relaxation time T1 of trityl OX063 was prominently reduced at cryogenic temperatures. The reduction of trityl OX063 electron T1 by Ho-doping is linked to the (13)C DNP improvement in light of the thermodynamic picture of DNP. Moreover, the presence of Ho-DOTA in the dissolution liquid at room temperature has negligible reduction effect on liquid-state (13)C T1, in contrast to Gd(3+)-doping which drastically reduces the (13)C T1. The results here suggest that Ho(3+)-doping is advantageous over Gd(3+) in terms of preservation of hyperpolarized state-an important aspect to consider for in vitro and in vivo NMR or imaging (MRI) experiments where a considerable preparation time is needed to administer the hyperpolarized (13)C liquid. PMID:27424954

  19. 5. East portal of Tunnel 28, view to southsouthwest, 135mm ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. East portal of Tunnel 28, view to south-southwest, 135mm lens. Shed above portal appears to have housed machinery connected with a counterweighted curtain mechanism used to help dissipate smoke from this 3,209-foot tunnel during the days of steam locomotive use - Central Pacific Transcontinental Railroad, Tunnel No. 28, Milepost 134.75, Applegate, Placer County, CA

  20. 10. Southeast end; view to northwest, 65mm lens. Note evidence ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. Southeast end; view to northwest, 65mm lens. Note evidence of extreme building failure caused by adjacent railroad cut, which necessitated building demolition. (Vignetting due to extreme use of camera swing necessitated by lack of space to position camera otherwise.) - Benicia Arsenal, Powder Magazine No. 5, Junction of Interstate Highways 680 & 780, Benicia, Solano County, CA

  1. 2. West portal of Tunnel 1, view to northeast, 135mm ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. West portal of Tunnel 1, view to northeast, 135mm lens. Like the new tunnels built during this period, Tunnel 1 received a new concrete portal face with granite masonry voussoirs and coping. - Central Pacific Transcontinental Railroad, Tunnel No. 1, Milepost 164.34, Blue Canyon, Placer County, CA

  2. 5. East portal of Tunnel 18, view to westsouthwest, 135mm ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. East portal of Tunnel 18, view to west-southwest, 135mm lens. The train exiting the tunnel, though northbound toward Portland, is considered an eastbound train on the Southern Pacific (see explanation above). - Southern Pacific Railroad Natron Cutoff, Tunnel No. 18, Milepost 410, Dorris, Siskiyou County, CA

  3. 1. East portal of Tunnel 3, view to west, 135mm ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. East portal of Tunnel 3, view to west, 135mm lens. This tunnel was photographed to provide context, because even though somewhat enlarged, it illustrates the nature of the unlined hard rock tunnels typical of the original Central Pacific construction in 1868. - Central Pacific Transcontinental Railroad, Tunnel No. 3, Milepost 180.65, Cisco, Placer County, CA

  4. Detail, typical window fenestrations, east façade, view to westnorthwest (135mm ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Detail, typical window fenestrations, east façade, view to west-northwest (135mm lens). Note "timber" header, adobe bench in front of window. - Burton Park, Club House & Amphitheater, Adjacent ot south end of Chestnut Avenue, San Carlos, San Mateo County, CA

  5. 3. West portal of Tunnel 26, view to northeast, 135mm ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. West portal of Tunnel 26, view to northeast, 135mm lens. Note use of granite voussoirs and coping on this otherwise all-reinforced concrete structure. - Central Pacific Transcontinental Railroad, Tunnel No. 26, Milepost 133.29, Applegate, Placer County, CA

  6. 2. West portal of Snowshed 29, view to east, 135mm ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. West portal of Snowshed 29, view to east, 135mm lens. Note the heavy timber frame, with battered posts to carry the tremendous snow loads of winter. - Central Pacific Transcontinental Railroad, Tunnel No. 41, Milepost 193.3, Donner, Placer County, CA

  7. 3. East portal of Tunnel 34, view to southsouthwest, 135mm ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. East portal of Tunnel 34, view to south-southwest, 135mm lens with electronic flash fill. Note the shift, in these later tunnels east of Colfax, to concrete portal faces with granite masonry voussoirs and coping. - Central Pacific Transcontinental Railroad, Tunnel No. 34, Milepost 145.4, Colfax, Placer County, CA

  8. Building 810, oblique view to eastsoutheast, 90mm lens. Note buttressed ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Building 810, oblique view to east-southeast, 90mm lens. Note buttressed end wall extensions into which main doors nest. - Travis Air Force Base, B-36 Hangar, Between Woodskill Avenue & Ellis, adjacent to Taxiway V & W, Fairfield, Solano County, CA

  9. 14. Main room; view no southwest, 65mm lens with electronic ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    14. Main room; view no southwest, 65mm lens with electronic flash illumination. The mountain visible through the windows was a landmark for the camp population. - Tule Lake Project Jail, Post Mile 44.85, State Route 139, Newell, Modoc County, CA

  10. 3. West portal of Tunnel 18, view to northeast, 135mm ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. West portal of Tunnel 18, view to northeast, 135mm lens. Note the use of concrete face and wingwalls, with dressed stone voussoirs, wingwall coping, parapet with stone belt course and coping, and coursed stone masonry slope protection flanking the portal. - Southern Pacific Railroad Natron Cutoff, Tunnel No. 17, Milepost 408, Dorris, Siskiyou County, CA

  11. Rotman lens for mm-wavelengths

    NASA Astrophysics Data System (ADS)

    Hall, Leonard T.; Hansen, Hedley J.; Abbott, Derek

    2002-11-01

    The 77 GHz band has been reserved for intelligent cruise control in luxury cars and some public transport services in America and the United Kingdom. The Rotman lens offers a cheap and compact means to extend the single beam systems generally used, to fully functional beam staring arrangements. Rotman lenses have been built for microwave frequencies with limited success. The flexibility of microstrip transmission lines and the advent of fast accurate simulation packages allow practical Rotman lenses to be designed at mm-wavelengths. This paper discusses the limitations of the conventional design approach and predicts the performance of a new Rotman lens designed at 77 GHz.

  12. Presence of an HO-1 expression threshold in renal glomeruli.

    PubMed

    Detsika, Maria G; Atsaves, Vassileios; Papalois, Apostolos; Lianos, Elias A

    2015-12-01

    This article reports data describing HO-1 expression patterns of heme oxygenase (HO)-1 in isolated rat glomeruli and in cultured glomerular epithelial cells (GEC) in response to its natural substrate heme. Qualitative and quantitative data are presented to support presence of a HO-1 expression threshold in glomeruli but not in GEC. Interpretation of our data and further insight into HO-1 expression pattern in glomeruli may be found in 'HO-1 expression control in the rat glomerulus' [1]. PMID:26702422

  13. Influence of pH on Ca2+ current and its control of electrical and Ca2+ signaling in ventricular myocytes

    PubMed Central

    Saegusa, Noriko; Moorhouse, Emma; Vaughan-Jones, Richard D.

    2011-01-01

    Modulation of L-type Ca2+ current (ICa,L) by H+ ions in cardiac myocytes is controversial, with widely discrepant responses reported. The pH sensitivity of ICa,L was investigated (whole cell voltage clamp) while measuring intracellular Ca2+ (Ca2+i) or pHi (epifluorescence microscopy) in rabbit and guinea pig ventricular myocytes. Selectively reducing extracellular or intracellular pH (pHo 6.5 and pHi 6.7) had opposite effects on ICa,L gating, shifting the steady-state activation and inactivation curves to the right and left, respectively, along the voltage axis. At low pHo, this decreased ICa,L, whereas at low pHi, it increased ICa,L at clamp potentials negative to 0 mV, although the current decreased at more positive potentials. When Ca2+i was buffered with BAPTA, the stimulatory effect of low pHi was even more marked, with essentially no inhibition. We conclude that extracellular H+ ions inhibit whereas intracellular H+ ions can stimulate ICa,L. Low pHi and pHo effects on ICa,L were additive, tending to cancel when appropriately combined. They persisted after inhibition of calmodulin kinase II (with KN-93). Effects are consistent with H+ ion screening of fixed negative charge at the sarcolemma, with additional channel block by H+o and Ca2+i. Action potential duration (APD) was also strongly H+ sensitive, being shortened by low pHo, but lengthened by low pHi, caused mainly by H+-induced changes in late Ca2+ entry through the L-type Ca2+ channel. Kinetic analyses of pH-sensitive channel gating, when combined with whole cell modeling, successfully predicted the APD changes, plus many of the accompanying changes in Ca2+ signaling. We conclude that the pHi-versus-pHo control of ICa,L will exert a major influence on electrical and Ca2+-dependent signaling during acid–base disturbances in the heart. PMID:22042988

  14. Basal Ca2+ and the oscillation of Ca2+ in caffeine-treated bullfrog sympathetic neurones.

    PubMed Central

    Nohmi, M; Hua, S Y; Kuba, K

    1992-01-01

    1. Effects of caffeine on the intracellular free Ca2+ concentration ([Ca2+]i) in single bullfrog sympathetic neurones in excised tissue were studied by recording Fura-2 fluorescence excited at 340, 361 or 380 nm and taking their ratios (R340/380 or R361/380). 2. Caffeine (3-10 mM) produced oscillation of [Ca2+]i and an 'apparent' decrease in the basal level of [Ca2+]i during a period between phasic rises. The mechanism of the latter effect was analysed in relation to the mechanism of the former. 3. Caffeine (3-10 mM) increased Fura-2 fluorescence in a range of excitation wavelength from 330 to 390 nm. The ratios of fluorescences, R340/380 and R361/380, however, were not significantly affected by caffeine. These results suggest that the 'apparent' reduction in the basal [Ca2+]i seen as a decrease in R340/380 or R361/380 results from a true decrease in [Ca2+]i. 4. Caffeine-induced decrease in [Ca2+]i persisted for every period between phasic rises of [Ca2+]i during [Ca2+]i oscillation, and after the blockade of [Ca2+]i oscillation by ryanodine. The decrease in the latter condition lasted for more than 20 min. 5. The decrease in the basal [Ca2+]i depended on the external Ca2+ concentration and was not mimicked by the action of cyclic nucleotides. 6. Possible mechanisms underlying the decrease in the basal [Ca2+]i produced by caffeine (effects on Ca2+ transport at the cell or Ca(2+)-storing organelle membrane) and their significance in relation to the [Ca2+]i oscillation were discussed. PMID:1432716

  15. Thermochemistry of HO2 + HO2 → H2O4: Does HO2 Dimerization Affect Laboratory Studies?

    PubMed

    Sprague, Matthew K; Irikura, Karl K

    2015-07-01

    Self-reaction is an important sink for the hydroperoxy radical (HO2) in the atmosphere. It has been suggested (Denis, P. A.; Ornellas, F. R. J. Phys. Chem. A, 2009, 113 (2), 499-506) that the minor product hydrogen tetroxide (HO4H) may act as a reservoir of HO2. Here, we compute the thermochemistry of HO2 self-reactions to determine if either HO4H or the cyclic hydrogen-bound dimer (HO2)2 can act as reservoirs. We computed electronic energies using coupled-cluster calculations in the complete basis set limit, CCSD(T)/CBS[45]//CCSD(T)/cc-pVTZ. Our model chemistry includes corrections for vibrational anharmonicity in the zero-point energy and vibrational partition functions, core-valence correlation, scalar relativistic effects, diagonal Born-Oppenheimer, spin-orbit splitting, and higher-order corrections. We compute the Gibbs energy of dimerization to be (-20.1 ± 1.6) kJ/mol at 298.15 K (2σ uncertainty), and (-32.3 ± 1.5) kJ/mol at 220 K. For atmospherically relevant [HO2] = 10(8) molecules per cm(3), our thermochemistry indicates that dimerization will be negligible, and thus H2O4 species are atmospherically unimportant. Under conditions used in laboratory experiments ([HO2] > 10(12) molecules per cm(3), 220 K), H2O4 formation may be significant. We compute two absorption spectra that could be used for laboratory detection of HO4H: the OH stretch overtone (near-IR) and electronic (UV) spectra. PMID:26066551

  16. Effects of Ca antagonists on Ca fluxes in resistance vessels

    SciTech Connect

    Cauvin, C.; Saida, K.; van Breemen, C.

    1982-01-01

    Researchers have examined contractions and /sup 45/Ca fluxes induced by norepinephrine (NE) and 80 mM potassium (high K) depolarization and their inhibition by dilitazem in rabbit mesenteric resistance vessels. Contraction induced by both NE and high K depended almost completely on extracellular Ca. Dose-response curves for diltiazem inhibition of NE (10(-5) M) and high K contractions showed ED50 values of 1 X 10(-8) and 6 X 10(-7) M, respectively, indicating that the receptor-operated channel (ROC) was more sensitive than the potential-operated channel (POC) to the action of diltiazem. Diltiazem (10(-6) M) was shown to inhibit NE- and 80 mM K-stimulated /sup 45/Ca influx effectively by 87 +/- 15 and 85 +/- 10%, respectively. Comparison of these data to those obtained from aorta suggest that although the sensitivity of the POC is approximately the same in aorta and mesenteric resistance vessels, the sensitivity of the ROC is much greater in the latter. This increased sensitivity is paralleled by a greatly decreased role of intracellular Ca release in NE contraction in mesenteric resistance vessels.

  17. Kinetics and stoichiometry of coupled Na efflux and Ca influx (Na/Ca exchange) in barnacle muscle cells.

    PubMed

    Rasgado-Flores, H; Santiago, E M; Blaustein, M P

    1989-06-01

    Coupled Na+ exit/Ca2+ entry (Na/Ca exchange operating in the Ca2+ influx mode) was studied in giant barnacle muscle cells by measuring 22Na+ efflux and 45Ca2+ influx in internally perfused, ATP-fueled cells in which the Na+ pump was poisoned by 0.1 mM ouabain. Internal free Ca2+, [Ca2+]i, was controlled with a Ca-EGTA buffering system containing 8 mM EGTA and varying amounts of Ca2+. Ca2+ sequestration in internal stores was inhibited with caffeine and a mitochondrial uncoupler (FCCP). To maximize conditions for Ca2+ influx mode Na/Ca exchange, and to eliminate tracer Na/Na exchange, all of the external Na+ in the standard Na+ sea water (NaSW) was replaced by Tris or Li+ (Tris-SW or LiSW, respectively). In both Na-free solutions an external Ca2+ (Cao)-dependent Na+ efflux was observed when [Ca2+]i was increased above 10(-8) M; this efflux was half-maximally activated by [Ca2+]i = 0.3 microM (LiSW) to 0.7 microM (Tris-SW). The Cao-dependent Na+ efflux was half-maximally activated by [Ca2+]o = 2.0 mM in LiSW and 7.2 mM in Tris-SW; at saturating [Ca2+]o, [Ca2+]i, and [Na+]i the maximal (calculated) Cao-dependent Na+ efflux was approximately 75 pmol#cm2.s. This efflux was inhibited by external Na+ and La3+ with IC50's of approximately 125 and 0.4 mM, respectively. A Nai-dependent Ca2+ influx was also observed in Tris-SW. This Ca2+ influx also required [Ca2+]i greater than 10(-8) M. Internal Ca2+ activated a Nai-independent Ca2+ influx from LiSW (tracer Ca/Ca exchange), but in Tris-SW virtually all of the Cai-activated Ca2+ influx was Nai-dependent (Na/Ca exchange). Half-maximal activation was observed with [Na+]i = 30 mM. The fact that internal Ca2+ activates both a Cao-dependent Na+ efflux and a Nai-dependent Ca2+ influx in Tris-SW implies that these two fluxes are coupled; the activating (intracellular) Ca2+ does not appear to be transported by the exchanger. The maximal (calculated) Nai-dependent Ca2+ influx was -25 pmol/cm2.s. At various [Na+]i between 6 and 106 mM

  18. A caffeine- and ryanodine-sensitive Ca2+ store in bullfrog sympathetic neurones modulates effects of Ca2+ entry on [Ca2+]i.

    PubMed Central

    Friel, D D; Tsien, R W

    1992-01-01

    1. We studied how in changes in cytosolic free Ca2+ concentration ([Ca2+]i) produced by voltage-dependent Ca2+ entry are influenced by a caffeine-sensitive Ca2+ store in bullfrog sympathetic neurones. Ca2+ influx was elicited by K+ depolarization and the store was manipulated with either caffeine or ryanodine. 2. For a time after discharging the store with caffeine and switching to a caffeine-free medium: (a) [Ca2+]i was depressed by up to 40-50 nM below the resting level, (b) caffeine responsiveness was diminished, and (c) brief K+ applications elicited [Ca2+]i responses with slower onset and faster recovery than controls. These effects were more pronounced as the conditioning caffeine concentration was increased over the range 1-30 mM. 3. [Ca2+]i, caffeine and K+ responsiveness recovered in parallel with a half-time of approximately 2 min. Recovery required external Ca2+ and was speeded by increasing the availability of cytosolic Ca2+, suggesting that it reflected replenishment of the store at the expense of cytosolic Ca2+. 4. During recovery, Ca2+ entry stimulated by depolarization had the least effect on [Ca2+]i when the store was filling most rapidly. This suggests that the effect of Ca2+ entry on [Ca2+]i is modified, at least in part, because some of the Ca2+ which enters the cytosol during stimulation is taken up by the store as it refills. 5. Further experiments were carried out to investigate whether the store can also release Ca2+ in response to stimulated Ca2+ entry. In the continued presence of caffeine at a low concentration (1 mM), high K+ elicited a faster and larger [Ca2+]i response compared to controls; at higher concentrations of caffeine (10 and 30 mM) responses were depressed. 6. Ryanodine (1 microM) reduced the rate at which [Ca2+]i increased with Ca2+ entry, but not to the degree observed after discharging the store. At this concentration, ryanodine completely blocked responses to caffeine but had no detectable effect on Ca2+ channel current

  19. Gonadotropin-releasing hormone-induced Ca2+ transients in single identified gonadotropes require both intracellular Ca2+ mobilization and Ca2+ influx.

    PubMed Central

    Shangold, G A; Murphy, S N; Miller, R J

    1988-01-01

    We examined the effects of gonadotropin-releasing hormone (GnRH) on the intracellular free Ca2+ concentration ([Ca2+]i) in single rat anterior pituitary gonadotropes identified by a reverse hemolytic plaque assay. Concentrations of GnRH greater than 10 pM elicited increases in [Ca2+]i in identified cells but not in others. In contrast, depolarization induced by 50 mM K+ increased [Ca2+]i in all cells. Ca2+ transients induced by GnRH exhibited a complex time course. After an initial rapid rise, the [Ca2+]i fell to near basal levels only to be followed by a secondary extended rise and fall. Analysis of the Ca2+ transients on a rapid time base revealed that responses frequently consisted of several rapid oscillations in [Ca2+]i. Removal of extracellular Ca2+ or addition of the dihydropyridine Ca2+-channel blocker nitrendipine completely blocked the secondary rise in [Ca2+]i but had no effect whatsoever on the initial spike. Nitrendipine also blocked 50 mM K+-induced increases in [Ca2+]i in identified gonadotropes. The secondary rise induced by GnRH could be enhanced by a phorbol ester in a nitrendipine-sensitive fashion. Multiple spike responses to GnRH stimulation of the same cell could only be obtained if subsequent Ca2+ influx was permitted either by allowing a secondary rise to occur or by producing a Ca2+ transient by depolarizing the cells with 50 mM K+. It therefore appears that the response to GnRH consists of an initial phase of Ca2+ mobilization, probably mediated by inositol trisphosphate, and a subsequent phase of Ca2+ influx through nitrendipine-sensitive Ca2+ channels that may be activated by protein kinase C. The relative roles of these phases in the control of gonadotropin secretion are discussed. Images PMID:3045819

  20. 4. Credit USAF, ca. 1945. Original housed in the Photograph ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. Credit USAF, ca. 1945. Original housed in the Photograph Files, AFFTC/HO, Edwards AFB, California. Low level oblique aerial view of Muroc Flight Test Base (North Base), looking southwest along flightline. HANG-P-A hangar (Building 4505) is in the right foreground. A Bell XP-59A Airacomet, the United States military's first jet propelled aircraft, is being towed on the apron toward the control tower. Other aircraft in the foreground include Douglas DC-3s, North American Aviation P-51 Mustangs, and Lockheed P-38 Lightnings. - Edwards Air Force Base, North Base, North Base Road, Boron, Kern County, CA

  1. 7. Credit USAF, ca. 1952. Original housed in the Photograph ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. Credit USAF, ca. 1952. Original housed in the Photograph Files, AFFTC/HO, Edwards AFB, California. Oblique aerial view of North Base AFFTC (Air Force Flight Test Center) looking west northwest. The flight line at the edge of Rogers Dry Lake appears in the foreground, served by the facility's four hangars. Temporary structures beyond the hangars were demolished later in the 1950s. The fence that formerly surrounded the swimming pool in earlier photos has been taken down. In the distance lies the Jet Propulsion Laboratory Edwards Test Station, in its pre-1953 configuration. - Edwards Air Force Base, North Base, North Base Road, Boron, Kern County, CA

  2. 6. Credit USAF, ca. 1947. Original housed in the Photograph ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. Credit USAF, ca. 1947. Original housed in the Photograph Files, AFFTC/HO, Edwards AFB, California. Interior of Building 4401 (or possibly 4402) looking east at hangar doors with a North American Aviation XB-45 Tornado jet aircraft in the foreground. This view illustrates why the series of sliding doors and wide, high interior clearances were necessary to accommodate large aircraft. Note configuration of wooden trusses supporting the roof. - Edwards Air Force Base, North Base, Hangar No. 1, First & B Streets, Boron, Kern County, CA

  3. Prediction of Stereochemistry using Q2MM.

    PubMed

    Hansen, Eric; Rosales, Anthony R; Tutkowski, Brandon; Norrby, Per-Ola; Wiest, Olaf

    2016-05-17

    The standard method of screening ligands for selectivity in asymmetric, transition metal-catalyzed reactions requires experimental testing of hundreds of ligands from ligand libraries. This "trial and error" process is costly in terms of time as well as resources and, in general, is scientifically and intellectually unsatisfying as it reveals little about the underlying mechanism behind the selectivity. The accurate computational prediction of stereoselectivity in enantioselective catalysis requires adequate conformational sampling of the selectivity-determining transition state but has to be fast enough to compete with experimental screening techniques to be useful for the synthetic chemist. Although electronic structure calculations are accurate and general, they are too slow to allow for sampling or fast screening of ligand libraries. The combined requirements can be fulfilled by using appropriately fitted transition state force fields (TSFFs) that represent the transition state as a minimum and allow fast conformational sampling using Monte Carlo. Quantum-guided molecular mechanics (Q2MM) is an automated force field parametrization method that generates accurate, reaction-specific TSFFs by fitting the functional form of an arbitrary force field using only electronic structure calculations by minimization of an objective function. A key feature that distinguishes the Q2MM method from many other automated parametrization procedures is the use of the Hessian matrix in addition to geometric parameters and relative energies. This alleviates the known problems of overfitting of TSFFs. After validation of the TSFF by comparison to electronic structure results for a test set and available experimental data, the stereoselectivity of a reaction can be calculated by summation over the Boltzman-averaged relative energies of the conformations leading to the different stereoisomers. The Q2MM method has been applied successfully to perform virtual ligand screens on a range of

  4. The new 800mm reflecting telescope

    NASA Astrophysics Data System (ADS)

    Teske, Hans-Joachim

    The design and capabilities of the 800-mm Ritchey-Chretien system are described. The optical system of the telescope has an aperture ratio of 1:8; is suitable for photography in a 1.5 deg field with photoplates of 16 x 16 cm; and consists of primary and secondary hyperbolically deformed mirrors. The attachment of the mirrors, position rotator, and offset guider to the tube, which is a truss structure, is examined. The mount for the telescope is an equatorial fork type. The electronic control system is a 16-bit microcomputer system; the functions of the control system are discussed. The 8-m polyester dome of the telescope consists of a supporting steel structure carrying shell elements of glass fiber-reinforced polyester resins. Consideration is given to the auxiliary devices of the telescope.

  5. Prediction of Stereochemistry using Q2MM

    PubMed Central

    2016-01-01

    Conspectus The standard method of screening ligands for selectivity in asymmetric, transition metal-catalyzed reactions requires experimental testing of hundreds of ligands from ligand libraries. This “trial and error” process is costly in terms of time as well as resources and, in general, is scientifically and intellectually unsatisfying as it reveals little about the underlying mechanism behind the selectivity. The accurate computational prediction of stereoselectivity in enantioselective catalysis requires adequate conformational sampling of the selectivity-determining transition state but has to be fast enough to compete with experimental screening techniques to be useful for the synthetic chemist. Although electronic structure calculations are accurate and general, they are too slow to allow for sampling or fast screening of ligand libraries. The combined requirements can be fulfilled by using appropriately fitted transition state force fields (TSFFs) that represent the transition state as a minimum and allow fast conformational sampling using Monte Carlo. Quantum-guided molecular mechanics (Q2MM) is an automated force field parametrization method that generates accurate, reaction-specific TSFFs by fitting the functional form of an arbitrary force field using only electronic structure calculations by minimization of an objective function. A key feature that distinguishes the Q2MM method from many other automated parametrization procedures is the use of the Hessian matrix in addition to geometric parameters and relative energies. This alleviates the known problems of overfitting of TSFFs. After validation of the TSFF by comparison to electronic structure results for a test set and available experimental data, the stereoselectivity of a reaction can be calculated by summation over the Boltzman-averaged relative energies of the conformations leading to the different stereoisomers. The Q2MM method has been applied successfully to perform virtual ligand

  6. mm-wave solid state amplifiers

    NASA Astrophysics Data System (ADS)

    Wolfert, P. H.; Crowley, J. D.; Fank, F. B.

    The development of mm-wave amplifiers using InP Gunn diodes is reviewed including a low-noise eight-stage amplifier for replacement of a Ka-band TWTA and a three-stage amplifier for the 42.5 to 44.5 range with an output power of 100 mW and 20 dB associated gain. A detailed description of a three-stage amplifier for the 54 to 58 GHz range is given with 100 mW output power and 15 dB associated gain, a small signal gain of 30 dB and an N.F. of 15.5 to 16.5 dB. The design of a broad band, low-loss V-band circulator, which was used in the amplifier, is described.

  7. Ho:YLF pumped HBr laser.

    PubMed

    Botha, L R; Bollig, C; Esser, M J D; Campbell, R N; Jacobs, C; Preussler, D R

    2009-10-26

    A Ho:YLF laser pumped HBr molecular laser was developed that produced up to 2.5 mJ of energy in the 4 micron wavelength region. The Ho:YLF laser was fiber pumped using a commercial Tm:fibre laser. The Ho:YLF laser was operated in a single longitudinal mode via injection seeding with a narrow band diode laser which in turn was locked to one of the HBr transitions. The behavior of the HBr laser was described using a rate equation mathematical model and this was solved numerically. Good agreement both qualitatively and quantitatively between the model and experimental results was obtained. PMID:19997290

  8. Isoflurane inhibits synaptic vesicle exocytosis through reduced Ca2+ influx, not Ca2+-exocytosis coupling

    PubMed Central

    Baumgart, Joel P.; Zhou, Zhen-Yu; Hara, Masato; Cook, Daniel C.; Hoppa, Michael B.; Ryan, Timothy A.; Hemmings, Hugh C.

    2015-01-01

    Identifying presynaptic mechanisms of general anesthetics is critical to understanding their effects on synaptic transmission. We show that the volatile anesthetic isoflurane inhibits synaptic vesicle (SV) exocytosis at nerve terminals in dissociated rat hippocampal neurons through inhibition of presynaptic Ca2+ influx without significantly altering the Ca2+ sensitivity of SV exocytosis. A clinically relevant concentration of isoflurane (0.7 mM) inhibited changes in [Ca2+]i driven by single action potentials (APs) by 25 ± 3%, which in turn led to 62 ± 3% inhibition of single AP-triggered exocytosis at 4 mM extracellular Ca2+ ([Ca2+]e). Lowering external Ca2+ to match the isoflurane-induced reduction in Ca2+ entry led to an equivalent reduction in exocytosis. These data thus indicate that anesthetic inhibition of neurotransmitter release from small SVs occurs primarily through reduced axon terminal Ca2+ entry without significant direct effects on Ca2+-exocytosis coupling or on the SV fusion machinery. Isoflurane inhibition of exocytosis and Ca2+ influx was greater in glutamatergic compared with GABAergic nerve terminals, consistent with selective inhibition of excitatory synaptic transmission. Such alteration in the balance of excitatory to inhibitory transmission could mediate reduced neuronal interactions and network-selective effects observed in the anesthetized central nervous system. PMID:26351670

  9. Isoflurane inhibits synaptic vesicle exocytosis through reduced Ca2+ influx, not Ca2+-exocytosis coupling.

    PubMed

    Baumgart, Joel P; Zhou, Zhen-Yu; Hara, Masato; Cook, Daniel C; Hoppa, Michael B; Ryan, Timothy A; Hemmings, Hugh C

    2015-09-22

    Identifying presynaptic mechanisms of general anesthetics is critical to understanding their effects on synaptic transmission. We show that the volatile anesthetic isoflurane inhibits synaptic vesicle (SV) exocytosis at nerve terminals in dissociated rat hippocampal neurons through inhibition of presynaptic Ca(2+) influx without significantly altering the Ca(2+) sensitivity of SV exocytosis. A clinically relevant concentration of isoflurane (0.7 mM) inhibited changes in [Ca(2+)]i driven by single action potentials (APs) by 25 ± 3%, which in turn led to 62 ± 3% inhibition of single AP-triggered exocytosis at 4 mM extracellular Ca(2+) ([Ca(2+)]e). Lowering external Ca(2+) to match the isoflurane-induced reduction in Ca(2+) entry led to an equivalent reduction in exocytosis. These data thus indicate that anesthetic inhibition of neurotransmitter release from small SVs occurs primarily through reduced axon terminal Ca(2+) entry without significant direct effects on Ca(2+)-exocytosis coupling or on the SV fusion machinery. Isoflurane inhibition of exocytosis and Ca(2+) influx was greater in glutamatergic compared with GABAergic nerve terminals, consistent with selective inhibition of excitatory synaptic transmission. Such alteration in the balance of excitatory to inhibitory transmission could mediate reduced neuronal interactions and network-selective effects observed in the anesthetized central nervous system. PMID:26351670

  10. Mechanisms of enhanced taurine release under Ca2+ depletion.

    PubMed

    Molchanova, Svetlana M; Oja, Simo S; Saransaari, Pirjo

    2005-10-01

    The sulfur-containing amino acid taurine is an inhibitory neuromodulator in the brain of mammals, as well as a key substance in the regulation of cell volumes. The effect of Ca(2+) on extracellular taurine concentrations is of special interest in the context of the regulatory mechanisms of taurine release. The aim of this study was to characterize the basal release of taurine in Ca(2+)-free medium using in vivo microdialysis of the striatum of anesthetized rats. Perfusion of Ca(2+)-free medium via a microdialysis probe evoked a sustained release of taurine (up to 180 % compared to the basal levels). The Ca(2+) chelator EGTA (1mM) potentiated Ca(2+) depletion-evoked taurine release. The substitution of CaCl(2) by choline chloride did not alter the observed effect. Ca(2+)-free solution did not significantly evoke release of taurine from tissue loaded with the competitive inhibitor of taurine transporter guanidinoethanesulfonate (1mM), suggesting that in Ca(2+) depletion taurine is released by the transporter operating in the outward direction. The volume-sensitive chloride channel blocker diisothiocyanostilbene-2,2'-disulfonate (1mM) did not attenuate the taurine release evoked by Ca(2+) depletion. The non-specific blocker of voltage-sensitive Ca(2+) channels NiCl(2) (0.65 mM) enhanced taurine release in the presence of Ca(2+). CdCl(2) (0.25 mM) had no effect under these conditions. However, both CdCl(2) and NiCl(2) attenuated the effect of Ca(2+)-free medium on the release of taurine. The data obtained imply the involvement of both decreased influx of Ca(2+) and increased non-specific influx of Na(+) through voltage-sensitive calcium channels in the regulation of transporter-mediated taurine release in Ca(2+) depletion. PMID:15982785

  11. Ca/sup 2 +/ and glucose uptake in adipocytes: evidence for biological activity of a Ca/sup 2 +/-palmitate complex

    SciTech Connect

    Thode, J.; Pershadsingh, H.A.; Shade, D.L.; McDonald, J.M.; Ladenson, J.H.

    1986-05-01

    A tightly bound form of Ca/sup 2 +/ in serum, thought to be a Ca/sup 2 +/-fatty acid complex, has been reported to cause accelerated Ca/sup 2 +/ uptake in bone cells. The authors therefore studied the effect of palmitic acid on Ca/sup 2 +/ accumulation and its influence on glucose transport in adipocytes. They assessed /sup 45/Ca/sup 2 +/ and /sup 14/C-D-glucose uptake into rat adipocytes from solutions containing: 4% (w/v) fatty acid-free albumin, 2.5 mM CaCl/sub 2/ (free (Ca/sup 2 +/)=1.30 mM), 140 mM NaCl, 3 mM Na phosphate, 1.4 mM MgSO/sub 4/, 5 mM D-glucose, 5 mM HEPES, pH 7.4 at 37/sup 0/C with and without 4 mM palmitate. Ca/sup 2 +/ was taken up by both rapid (< 30 sec), and slow (reaching steady state within 20 min) cellular accumulation phases. Palmitate increased the rapid binding phase of /sup 45/Ca/sup 2 +/ uptake from 2.10 +/- 0.13 to 3.03 +/- 0.16 fmol Ca/sup 2 +//cell and caused a 2 to 3-fold increase in the slow phase. Palmitate also increased glucose uptake by a mean of 225% above control. This increase was eliminated by a 15 min preincubation with the intracellular Ca/sup 2 +/ chelator, quin 2-AM (50 ..mu..M), implying that increased Ca/sup 2 +/ uptake was related to increased glucose transport. They conclude that the Ca/sup 2 +/-palmitate complex enhances Ca/sup 2 +/ uptake, which may be related to an increased ability for adipocytes to transport glucose. The Ca/sup 2 +/-palmitate complex may therefore represent a biologically active form of Ca/sup 2 +/.

  12. Local Measurement of Tropospheric HO(x)

    NASA Technical Reports Server (NTRS)

    Crosley, David R.

    1994-01-01

    In March of 1992 a workshop sponsored by NASA and NSF was held at SRI International to assess the current ability to measure atmospheric OH and HO2. The measurement techniques reviewed during the workshop for detection of OH included five laser-induced fluorescence schemes, five laser-based adsorption techniques, and four non-laser methods. Six instruments or instrument concepts for HO2 detection, including chemical amplification, conversion to OH with subsequent OH detection, or direct spectroscopic detection of the HO2 were also discussed. The conclusions from the workshop identify several measurement techniques for OH and HO2 that are ready for field tests. These have the ability to measure the radicals with sufficient sensitivity and accuracy to form meaningful comparison with atmospheric model predictions. The workshop conclusions also include recommendations for informal and formal intercomparison protocols.

  13. Low-Friction Minilaparoscopy Outperforms Regular 5-mm and 3-mm Instruments for Precise Tasks

    PubMed Central

    Firme, Wood A.; Lima, Diego L.; de Paula Lopes, Vladmir Goldstein; Montandon, Isabelle D.; Filho, Flavio Santos; Shadduck, Phillip P.

    2015-01-01

    Background and Objectives: Therapeutic laparoscopy was incorporated into surgical practice more than 25 y ago. Several modifications have since been developed to further minimize surgical trauma and improve results. Minilaparoscopy, performed with 2- to 3-mm instruments was introduced in the mid 1990s but failed to attain mainstream use, mostly because of the limitations of the early devices. Buoyed by a renewed interest, new generations of mini instruments are being developed with improved functionality and durability. This study is an objective evaluation of a new set of mini instruments with a novel low-friction design. Method: Twenty-two medical students and 22 surgical residents served as study participants. Three designs of laparoscopic instruments were evaluated: conventional 5 mm, traditional 3 mm, and low-friction 3 mm. The instruments were evaluated with a standard surgical simulator, emulating 4 exercises of various complexities, testing grasping, precise 2-handed movements, and suturing. The metric measured was time to task completion, with 5 replicates for every combination of instrument–exercise–participant. Results: For all 4 tasks, the instrument design that performed the best was the same in both the medical student and surgical resident groups. For the gross-grasping task, the 5-mm conventional instruments performed best, followed by the low-friction mini instruments. For the 3 more complex and precise tasks, the low-friction mini instruments outperformed both of the other instrument designs. Conclusion: In standard surgical simulator exercises, low-friction minilaparoscopic instruments outperformed both conventional 3- and 5-mm laparoscopic instruments for precise tasks. PMID:26390530

  14. A comparison of 9-inch, 70mm, and 35mm cameras

    NASA Technical Reports Server (NTRS)

    Clegg, R. H.; Scherz, J. P.

    1975-01-01

    Successful aerial photography depends on aerial cameras that provide acceptable photographs within the cost restrictions of the job. For topographic mapping where ultimate accuracy is required, only large-format mapping cameras will suffice. For mapping environmental patterns of vegetation, soils, or water pollution, 9-inch cameras often exceed accuracy and cost requirements, and small formats may be an overall better choice. In choosing the best camera for environmental mapping, relative capabilities and costs must be understood. This study compares resolution, photo interpretation potential, metric accuracy, and cost of 9-inch, 70 mm, and 35 mm cameras for obtaining simultaneous color and color-infrared photography for environmental mapping purposes.

  15. Energy levels of HoBr 63-

    NASA Astrophysics Data System (ADS)

    Tanner, Peter A.

    1986-12-01

    The excitation, electronic absorption and luminescence spectra of cubic Cs 2NaHoBr 6 have been recorded at temperatures down to that of liquid helium. The detailed spectral analyses enable comparisons to be made of the crystal-field splittings of Russell—Saunders terms with those in Cs 2NaHoCl 6. Under intense 647.1 nm laser excitation, luminescence is observed in the neat material in the spectral region between 17800 and 21750 cm -1.

  16. Ho:YAG laser arthroscopy of the knee

    NASA Astrophysics Data System (ADS)

    Sisto, Domenick J.; Blazina, Martin E.; Hirsh, Linda C.

    1994-09-01

    The HO:YAG laser is a near-contact laser with a capacity to ablate or cut tissues. The ablation function allows the surgeon to remove meniscal tissue, lyse and resect adhesions, melt loose bodies, and dissolve inflamed synovium. The cutting function of the laser is utilized to perform a lateral release or resect torn menisci. The laser can also be utilized to drill holes in Grade IV chondromalacic lesions to initiate a healing response. The laser has been embraced by orthopaedic surgeons because of its shape and versatility. The tip is only 2 mm wide and can be delivered into the tight posterior compartments of the knee with no damaging contact with the articular surfaces. The laser coagulates as it works and bleeding is minimized. The laser can function both as a cutting and ablating tool. The laser can also drill holes into subchondral bone to, hopefully, initiate a healing response.

  17. Spectroscopic properties and upconversion studies in Ho(3+) /Yb(3+) Co-doped calcium scandate with spectrally pure green emission.

    PubMed

    Li, Jing; Zhang, Jiahua; Hao, Zhendong; Zhang, Xia; Zhao, Jihong; Luo, Yongshi

    2013-12-16

    The optical properties of a Ho(3+) /Yb(3+) co-doped CaSc2 O4 oxide material are investigated in detail. The spectral properties are described as a function of doping concentrations. The efficient Yb(3+) →Ho(3+) energy transfer is observed. The transfer efficiency approaches 50 % before concentration quenching. The concentration-optimized sample exhibits a strong green emission accompanied with a weak red emission, showing perfect green monochromaticity. The results of the spectral distribution, power dependence, and lifetime measurements are presented. The green, red, and near-infrared (NIR) emissions around 545, 660, and 759 nm are assigned to the (5) F4 +(5) S2 →(5) I8 , (5) F5 →(5) I8 , and (5) F4 +(5) S2 →(5) I7 transitions of Ho(3+) , respectively. The detailed study reveals the upconversion luminescence mechanism involved in a novel Ho(3+) /Yb(3+) co-doped CaSc2 O4 oxide material. PMID:24323855

  18. Voltage-gated Ca2+ entry and ryanodine receptor Ca2+-induced Ca2+ release in preglomerular arterioles.

    PubMed

    Fellner, Susan K; Arendshorst, William J

    2007-05-01

    We have previously shown that in afferent arterioles, angiotensin II (ANG II) involves activation of the inositol trisphosphate receptor (IP(3)R), activation of adenine diphosphoribose (ADPR) cyclase, and amplification of the initial IP(3)R-stimulated release of cytosolic Ca(2+) ([Ca(2+)](i)) from the sarcoplasmic reticulum (SR) (Fellner SK, Arendshorst WJ. Am J Physiol Renal Physiol 288: F785-F791, 2004). The response of the ryanodine receptor (RyR) to local increases in [Ca(2+)](i) is defined as calcium-induced calcium release (CICR). To investigate whether Ca(2+) entry via voltage-gated channels (VGCC) can stimulate CICR, we treated fura 2-loaded, freshly isolated afferent arterioles with KCl (40 mM; high KCl). In control arterioles, peak [Ca(2+)](i) increased by 165 +/- 10 nM. Locking the RyR in the closed position with ryanodine (100 microM) inhibited the [Ca(2+)](i) response by 59% (P < 0.01). 8-Br cADPR, a specific blocker of the ability of cyclic ADPR (cADPR) to sensitize the RyR to Ca(2+), caused a 43% inhibition. We suggest that the lower inhibition by 8-Br cADPR (P = 0.02, ryanodine vs. 8-Br cADPR) represents endogenously active ADPR cyclase. Depletion of SR Ca(2+) stores by inhibiting the SR Ca(2+)-ATPase with cyclopiazonic acid or thapsigargin blocked the [Ca(2+)](i) responses to KCl by 51% (P not significant vs. ryanodine or 8-Br cADPR). These data suggest that about half of the increase in [Ca(2+)](i) induced by high KCl is accomplished by activation of CICR through the ability of entered Ca(2+) to expose the RyR to high local concentrations of Ca(2+) and that endogenous cADPR contributes to the process. PMID:17190906

  19. 75 FR 52534 - Su Van Ho: Debarment Order

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-26

    ... Salmonella bacteria, with verification of such exportation or destruction by FDA. Mr. Ho concealed and... with Salmonella bacteria. As a result of his conviction, on June 10, 2010, FDA sent Mr. Ho a notice...

  20. Detection of Ca(2+)-binding proteins by electrophoretic migration in the presence of Ca2+ combined with 45Ca2+ overlay of protein blots

    SciTech Connect

    Garrigos, M.; Deschamps, S.; Viel, A.; Lund, S.; Champeil, P.; Moller, J.V.; le Maire, M. , Gif-sur-Yvette )

    1991-04-01

    When high affinity Ca(2+)-binding proteins like calmodulin, or proteins with a high Ca(2+)-binding capacity like calsequestrin, underwent sodium dodecyl sulfate-gel electrophoresis in Laemmli systems, their electrophoretic migration rates were much higher in gels containing 1 mM Ca2+ than in gels containing ethylene glycol bis(beta-aminoethyl ether) N,N{prime}-tetraacetic acid (EGTA). Replacement of EGTA by Ca2+ in the gel, combined with the blotting of electrophoretically separated proteins on polyvinylidene difluoride membranes and subsequent 45Ca2+ overlay, proved a very effective means of detecting Ca(2+)-binding proteins. This combined approach is important since artifacts occur in both techniques when used separately. We found that the usual procedure of adding Ca2+ to the sample before electrophoresis without including it in the gel itself permitted the detection of only very high affinity Ca(2+)-binding proteins.

  1. Planetary brightness temperature measurements at 8.6 mm and 3.1 mm wavelengths.

    NASA Technical Reports Server (NTRS)

    Ulich, B. L.; Cogdell, J. R.; Davis, J. H.

    1973-01-01

    New measurements of the sun, moon, Mercury, Venus, Mars, Jupiter, and Saturn at 3.1- and 8.6-mm wavelengths are given. The temperatures reported for the planets at 3.1-mm wavelength are higher than previous measurements in this wavelength range and change the interpretation of some planetary spectra. For Mercury, it is found that the mean brightness temperature is independent of wavelength and that a temperature-dependent thermal conductivity is not required to match the observations. In the case of Mars, the spectrum is shown to rise in the millimeter region, as simple models predict. For Jupiter, the need to recalculate the spectrum with recent models is demonstrated. The flux density scale proposed by Dent (1972) has been revised according to a more accurate determination of the millimeter brightness temperature of Jupiter.

  2. Oxidized CaMKII Triggers Atrial Fibrillation

    PubMed Central

    Purohit, Anil; Rokita, Adam G.; Guan, Xiaoqun; Chen, Biyi; Koval, Olha M.; Voigt, Niels; Neef, Stefan; Sowa, Thomas; Gao, Zhan; Luczak, Elizabeth D.; Stefansdottir, Hrafnhildur; Behunin, Andrew C.; Li, Na; El-Accaoui, Ramzi N.; Yang, Baoli; Swaminathan, Paari Dominic; Weiss, Robert M.; Wehrens, Xander H.T.; Song, Long-Sheng; Dobrev, Dobromir; Maier, Lars S.; Anderson, Mark E.

    2013-01-01

    Background Atrial fibrillation is a growing public health problem without adequate therapies. Angiotensin II (Ang II) and reactive oxygen species (ROS) are validated risk factors for atrial fibrillation (AF) in patients, but the molecular pathway(s) connecting ROS and AF is unknown. The Ca2+/calmodulin-dependent protein kinase II (CaMKII) has recently emerged as a ROS activated proarrhythmic signal, so we hypothesized that oxidized CaMKIIδ(ox-CaMKII) could contribute to AF. Methods and Results We found ox-CaMKII was increased in atria from AF patients compared to patients in sinus rhythm and from mice infused with Ang II compared with saline. Ang II treated mice had increased susceptibility to AF compared to saline treated WT mice, establishing Ang II as a risk factor for AF in mice. Knock in mice lacking critical oxidation sites in CaMKIIδ (MM-VV) and mice with myocardial-restricted transgenic over-expression of methionine sulfoxide reductase A (MsrA TG), an enzyme that reduces ox-CaMKII, were resistant to AF induction after Ang II infusion. Conclusions Our studies suggest that CaMKII is a molecular signal that couples increased ROS with AF and that therapeutic strategies to decrease ox-CaMKII may prevent or reduce AF. PMID:24030498

  3. 1. West portal of Tunnel 36, view to northeast, 135mm ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. West portal of Tunnel 36, view to northeast, 135mm lens. Note the notched wingwalls that originally held timber posts of the original timber snowsheds, miles of which once enclosed and protected the railroad from the ravages of Sierra winters. Note also that these tunnels, built in the 1920s, have dispensed with any use of stone masonry, and instead have all-concrete portals. - Central Pacific Transcontinental Railroad, Tunnel No. 36, Milepost 176.92, Yuba Pass, Nevada County, CA

  4. System performance advances of 18-mm and 16-mm subminiature image intensifier sensors

    NASA Astrophysics Data System (ADS)

    Thomas, Nils I.

    2000-11-01

    Night vision system design has been centered aroudn the An/AVS-6 and AN/PVS-7 night vision goggle systems for the past 20 years. Goggle performance has improved during this time through increased performance of the image intensifier sensor, primarily the Omni IV sensor from ITT Industries Night Vision. Most of this improvement has been at the optimal light level (1E-3 fc scene illumination). Recent advances in image sensor performance from the filmless Generation (Gen) IV sensors has increased the low light level performance of night vision devices from 0.3 cy/mr to 0.7 cy/mr. In addition, sensor packaging design requirements have forced night vision sensor manufactures to design light weight, small volume sensors. ITT recently has designed such a sensor in a 16-mm format. This sensor if 50% lighter, up to 50% shorter, and has design features that simplify the objective lens design. New night vision goggles have been, and are being, designed which reduce the perceived head-supported weight. This paper presents signal-to-noise ratio, halo, and other film-less sensor data and similar 16-mm subminiature sensor data. The resulting system performance data will be described. Finally, the system design improvements and relationships with the subminiature 16-mm subminiature sensor will be given.

  5. Ca2+-Dependent Regulation of Ca2+ Currents in Rat Primary Afferent Neurons: Role of CaMKII and the Effect of Injury

    PubMed Central

    Tang, Qingbo; Bangaru, Madhavi Latha Yadav; Kostic, Sandra; Pan, Bin; Wu, Hsiang-En; Koopmeiners, Andrew S.; Yu, Hongwei; Fischer, Gregory J.; McCallum, J. Bruce; Kwok, Wai-Meng; Hudmon, Andy

    2012-01-01

    Currents through voltage-gated Ca2+ channels (ICa) may be regulated by cytoplasmic Ca2+ levels ([Ca2+]c), producing Ca2+-dependent inactivation (CDI) or facilitation (CDF). Since ICa regulates sensory neuron excitability, altered CDI or CDF could contribute to pain generation after peripheral nerve injury. We explored this by manipulating [Ca2+]c while recording ICa in rat sensory neurons. In uninjured neurons, elevating [Ca2+]c with a conditioning prepulse (−15 mV, 2 s) inactivated ICa measured during subsequent test pulses (−15 mV, 5 ms). This inactivation was Ca2+-dependent (CDI), since it was decreased with elimination of Ca2+ influx by depolarization to above the ICa reversal potential, with high intracellular Ca2+ buffering (EGTA 10 mm or BAPTA 20 mm), and with substitution of Ba2+ for extracellular Ca2+, revealing a residual voltage-dependent inactivation. At longer latencies after conditioning (>6 s), ICa recovered beyond baseline. This facilitation also proved to be Ca2+-dependent (CDF) using the protocols limiting cytoplasmic Ca2+ elevation. Ca2+/calmodulin-dependent protein kinase II (CaMKII) blockers applied by bath (KN-93, myristoyl-AIP) or expressed selectively in the sensory neurons (AIP) reduced CDF, unlike their inactive analogues. Protein kinase C inhibition (chelerythrine) had no effect. Selective blockade of N-type Ca2+ channels eliminated CDF, whereas L-type channel blockade had no effect. Following nerve injury, CDI was unaffected, but CDF was eliminated in axotomized neurons. Excitability of sensory neurons in intact ganglia from control animals was diminished after a similar conditioning pulse, but this regulation was eliminated by injury. These findings indicate that ICa in sensory neurons is subject to both CDI and CDF, and that hyperexcitability following injury-induced loss of CDF may result from diminished CaMKII activity. PMID:22915116

  6. Highly efficient high power CW and Q-switched Ho:YLF laser

    NASA Astrophysics Data System (ADS)

    Kwiatkowski, J.

    2015-06-01

    An efficient operation of a Ho:YLF laser pumped by a Tm-doped fibre laser is reported. The research in a continuous-wave (CW) operation was done for two crystals of the same 0.5 at.%Ho dopant concentration and with different lengths (3×3×30 mm3 and 3×3×50 mm3). For an output coupling transmission of 20% and a crystal length of 50 mm, the maximum CWoutput power of 38.9 W for 81.4 W of incident pump power, corresponding to the slope efficiency of 52.3% and optical-to-optical conversion efficiency of 47.8% (determined with respect to the incident pump power) was achieved. The highest opti- cal-to-optical conversion efficiency of 70.2% with respect to the absorbed pump power was obtained. The influence of a heat-sink cooling water temperature on theCWlaser performance was studied. For a Q-switched operation the pulse repe- tition frequency (PRF) was changed from 2 to 10 kHz. The maximum average output power of 34.1 W at the PRF of 10 kHz was obtained for a 50 mm holmium crystal length. For 2 kHz PRF and 71.9 W of incident pump power, pulse energies of 13.7 mJ with a 21 ns FWHM pulse width corresponding to 652 kW peak power were recorded.

  7. Multimodality of Ca2+ signaling in rat atrial myocytes.

    PubMed

    Morad, Martin; Javaheri, Ashkan; Risius, Tim; Belmonte, Steve

    2005-06-01

    It has been suggested that the multiplicity of Ca(2+) signaling pathways in atrial myocytes may contribute to the variability of its function. This article reports on a novel Ca(2+) signaling cascade initiated by mechanical forces induced by "puffing" of solution onto the myocytes. Ca(i) transients were measured in fura-2 acetoxymethyl (AM) loaded cells using alternating 340- and 410-nm excitation waves at 1.2 kHz. Pressurized puffs of bathing solutions, applied by an electronically controlled micro-barrel system, activated slowly (approximately 300 ms) developing Ca(i) transients that lasted 1,693 +/- 68 ms at room temperature. Subsequent second and third puffs, applied at approximately 20 s intervals activated significantly smaller or no Ca(i) transients. Puff-triggered Ca(i) transients could be reactivated once again following caffeine (10 mM)-induced release of Ca(2+) from sarcoplasmic reticulum (SR). Puff-triggered Ca(i) transients were independent of [Ca(2+)](o), and activation of voltage-gated Ca(2+) or cationic stretch channels or influx of Ca(2+) on Na(+)/Ca(2+)exchanger, because puffing solution containing no Ca(2+), 10 microM diltiazem, 1 mM Cd(2+), 5 mM Ni(2+), or 100 microM Gd(3+) failed to suppress them. Puff-triggered Ca(i) transients were enhanced in paced compared to quiescent myocytes. Electrically activated Ca(i) transients triggered during the time course of puff-induced transients were unaltered, suggesting functionally separate Ca(2+) pools. Contribution of inositol 1,4,5-triphosphate (IP(3))-gated or mitochondrial Ca(2+) pools or modulation of SR stores by nitric oxide/nitric oxide synthase (NO/NOS) signaling were evaluated using 0.5 to 500 microM 2-aminoethoxydiphenyl borate (2-APB) and 0.1 to 1 microM carbonylcyanide-p-trifluoromethoxyphenylhydrazone (FCCP), and 1 mM Nomega-Nitro-L-arginine methyl ester (L-NAME) and 7-nitroindizole, respectively. Only FCCP appeared to significantly suppress the puff-triggered Ca(i) transients. It was

  8. Cytoprotective responses in HaCaT keratinocytes exposed to high doses of curcumin.

    PubMed

    Lundvig, Ditte M S; Pennings, Sebastiaan W C; Brouwer, Katrien M; Mtaya-Mlangwa, Matilda; Mugonzibwa, Emeria; Kuijpers-Jagtman, Anne Marie; Wagener, Frank A D T G; Von den Hoff, Johannes W

    2015-08-15

    Wound healing is a complex process that involves the well-coordinated interactions of different cell types. Topical application of high doses of curcumin, a plant-derived polyphenol, enhances both normal and diabetic cutaneous wound healing in rodents. For optimal tissue repair interactions between epidermal keratinocytes and dermal fibroblasts are essential. We previously demonstrated that curcumin increased reactive oxygen species (ROS) formation and apoptosis in dermal fibroblasts, which could be prevented by pre-induction of the cytoprotective enzyme heme oxygenase (HO)-1. To better understand the effects of curcumin on wound repair, we now assessed the effects of high doses of curcumin on the survival of HaCaT keratinocytes and the role of the HO system. We exposed HaCaT keratinocytes to curcumin in the presence or absence of the HO-1 inducers heme (FePP) and cobalt protoporphyrin (CoPP). We then assessed cell survival, ROS formation, and caspase activation. Curcumin induced caspase-dependent apoptosis in HaCaT keratinocytes via a ROS-dependent mechanism. Both FePP and CoPP induced HO-1 expression, but only FePP protected against curcumin-induced ROS formation and caspase-mediated apoptosis. In the presence of curcumin, FePP but not CoPP induced the expression of the iron scavenger ferritin. Together, our data show that the induction of ferritin, but not HO, protects HaCaT keratinocytes against cytotoxic doses of curcumin. The differential response of fibroblasts and keratinocytes to high curcumin doses may provide the basis for improving curcumin-based wound healing therapies. PMID:26071936

  9. Some Improvements in the Design of a CA/CV Moessbauer Velocity Drive

    SciTech Connect

    Seberini, Milan

    2008-10-28

    A constant velocity Moessbauer drive was built with velocity range {+-}15 mm/s and velocity resolution 0.005 mm/s. Based on good experience with its performance, a new universal CA/CV drive was designed. The new drive is supposed to have velocity range of {+-}80 mm/s with a velocity resolution below 0.002 mm/s.

  10. Presence of an HO-1 expression threshold in renal glomeruli

    PubMed Central

    Detsika, Maria G; Atsaves, Vassileios; Papalois, Apostolos; Lianos, Elias A.

    2015-01-01

    This article reports data describing HO-1 expression patterns of heme oxygenase (HO)-1 in isolated rat glomeruli and in cultured glomerular epithelial cells (GEC) in response to its natural substrate heme. Qualitative and quantitative data are presented to support presence of a HO-1 expression threshold in glomeruli but not in GEC. Interpretation of our data and further insight into HO-1 expression pattern in glomeruli may be found in ‘HO-1 expression control in the rat glomerulus’ [1]. PMID:26702422

  11. The LLAMA 12 m mm/sub-mm radiotelescope in the Andes

    NASA Astrophysics Data System (ADS)

    Lepine, Jacques; Edemundo Arnal, Marcelo; de Graauw, Thijs; Abraham, Zulema; Gimenez de Castro, Guillermo; de Gouveia Dal Pino, Elisabete; Morras, Ricardo; Larrarte, Juan; Viramontes, José; Finger, Ricardo; Kooi, Jacob; Reeves, Rodrigo; Beaklini, Pedro

    2015-08-01

    LLAMA (Large Latin American Millimetric Array) is a joint Argentinean-Brazilian project of a 12m mm/sub-mm radio telescope similar to the APEX antenna, to be installed at a site at 4800 m altitude near San Antonio de Los Cobres in the Salta Province in Argentine, at 150 km from ALMA. The scientific cases for single dish and VLBI observations include black holes and accretion disks, the molecular evolution of interstellar clouds, the structure of the Galaxy, the formation of galaxies, and much more. The antenna was ordered to the company Vertex Antennentechnik in June 2014, and the construction is progressing quickly; it will be installed at the site in 2016. The radio telescope will be equipped with up to six receivers covering bands similar to those of ALMA. Cryostats with room for 3 cartridges, constructed by NAOJ (Tokyo,Japan), will be installed in each of the two Nasmyth cabins. Among the first receivers we will have an ALMA band 9 provided by NOVA (Groningen, Holland) and a band 5 from the Chalmers University (Sweden). Other receivers are still being discussed at the time of submission of this abstract,At high frequencies, VLBI observations at high frequencies could be made with ALMA, APEX and ASTE, and Northern radiotelescopes. In this way, LLAMA will be a seed for a Latin-American VLBI network.

  12. Ca isotope cycling in a forested ecosystem

    NASA Astrophysics Data System (ADS)

    Holmden, Chris; Bélanger, Nicolas

    2010-02-01

    Reports of large Ca isotope fractionations between trees and soils prompted this study of a Boreal forest ecosystem near La Ronge, Saskatchewan, to improve understanding of this phenomenon. The results on five tree species (black spruce, trembling aspen, white spruce, jack pine, balsam poplar) confirm that nutrient Ca uptake by plants favors the light isotopes, thus driving residual Ca in plant available soil pools towards enrichment in the heavy isotopes. Substantial within-tree fraction occurs in tissues formed along the transpiration stream, with low δ 44Ca values in fine roots (2 mm), intermediate values in stemwood, and high values in foliage. Separation factors between different plant tissues are similar between species, but the initial fractionation step in the tips of the fine roots is species specific, and/or sensitive to the local soil environment. Soil water δ 44Ca values appear to increase with depth to at least 35 cm below the top of the forest floor, which is close to the deepest level of fine roots. The heavy plant fractionated signature of Ca in the finely rooted upper soils filters downward where it is retained on ion exchange sites, leached into groundwater, and discharged into surface waters. The relationship between Ca uptake by tree fine roots and the pattern of δ 44Ca enrichment with soil depth was modeled for two Ca pools: the forest floor (litter) and the underlying (upper B) mineral soil. Six study plots were investigated along two hillside toposequences trending upwards from a first order stream. We used allometric equations describing the Ca distribution in boreal tree species to calculate weighted average δ 44Ca values for the stands in each plot and estimate Ca uptake rates. The δ 44Ca value of precipitation was measured, and soil weathering signatures deduced, by acid leaching of lower B mineral soils. Steady state equations were used to derive a set of model Ca fluxes and fractionation factors for each plot. The model reproduces

  13. Sticking of HO2 on fatty acids aggregates

    NASA Astrophysics Data System (ADS)

    Vardanega, Delphine; Briquez, Stéphane; Duflot, Denis; Monnerville, Maurice; Toubin, Céline

    2015-04-01

    Models of atmospheric chemistry are widely used to perform projections of future changes in the chemical composition of the global troposphere, including changes in climate related greenhouse gases and aerosol particles. However, large uncertainties are still associated with the chemistry implemented in these models, which in turn can lead to inaccurate long-term predictions. The proposed work seeks to improve our understanding of the oxidative capacity of the atmosphere, which drives the lifetime of trace gases, and therefore atmospheric composition. Recent measurements [1] of free radicals made in forested environments characterized by low levels of nitrogen oxides (NOx = NO and NO2) indicate that current models of atmospheric chemistry tend to overestimate the concentration of peroxy radicals (HO2 and RO2). An overestimation of peroxy radicals is an important issue since these radicals are the main precursors of the hydroxyl radical (OH), the most important atmospheric oxidant during daytime. This issue could lead to a significant overestimation of the oxidative capacity of the global atmosphere since more than 86% of the Earth surface is covered by forests, oceans, and polar regions. An analysis of this dataset indicates that the missing sink could be due to an underestimation of the rates of RO2+HO2 reactions, and/or the uptake of peroxy radicals onto aerosol particles. A thorough evaluation of scientific studies published in the literature shows that there is a lack of kinetic and mechanistic data to correctly assess the contribution of these two loss pathways of peroxy radicals in low NOx environments. Classical molecular dynamics simulations, using the Gromacs package [2], are performed to study the interaction of HO2 with organic (carboxylic acid) aerosols. The effect of the presence of water molecules on the surface are also be investigated. These calculations provide theoretical values for observable quantities such as uptake and mass accommodation

  14. Teaching Evolutionary Mechanisms: Genetic Drift and M&M's.

    ERIC Educational Resources Information Center

    Staub, Nancy L.

    2002-01-01

    Describes a classroom activity that teaches the mechanism of genetic drift to undergraduates. Illustrates a number of concepts that are critical in developing evolution literacy by sampling M&M milk chocolate candies. (MM)

  15. AN ENZYME LINKED IMMUNOSORBENT ASSAY FOR THE HO-1 ISOFORM OF HEME OXYGENASE

    EPA Science Inventory

    AN ENZYME LINKED IMMUNOSORBENT ASSAY FOR THE HO-1 ISOFORM OF HEME OXYGENASE

    Heme oxygenase (HO) occurs in biological tissues as two major isoforms HO-1 and HO-2. HO-1 is inducible by many treatments, particularly oxidative stress-related conditions such as depletion of gl...

  16. Kinetics of the reaction HO2 + NO2 + M yields HO2NO2 + M

    NASA Technical Reports Server (NTRS)

    Sander, S. P.; Peterson, M. E.

    1984-01-01

    The flash photolysis/ultraviolet absorption technique was used to measure the rate constants for the reaction HO2 + NO2 + M yields HO2NO2 + M over the pressure range 50-700 torr and temperature range 229-362 K using He, O2, and N2 as diluent gases. The data were fit to the expression derived by Troe (1979) and co-workers for describing the pressure and temperature dependence of reactions in the falloff region. By combining these data with recent measurements of the rate constant for HO2NO2 thermal decomposition values of 73.8 + or - 2 eu for the standard entropy and -12.6 + or - kcal/mol for the standard enthalpy of formation of HO2NO2 were obtained. A significant enhancement in the rate constant was observed when water vapor was added to the system.

  17. Luminal Ca2+ promoting spontaneous Ca2+ release from inositol trisphosphate-sensitive stores in rat hepatocytes.

    PubMed Central

    Missiaen, L; Taylor, C W; Berridge, M J

    1992-01-01

    1. Spontaneous Ca2+ release from the inositol 1,4,5-trisphosphate (InsP3)-sensitive stores in permeabilized hepatocytes was monitored using Fluo-3 to measure the free [Ca2+] of the medium bathing the cells. 2. Permeabilized cells rapidly sequestered Ca2+, reducing the [Ca2+] to 103 +/- 5 nM. Under conditions that depended critically upon cell density and the amount of Ca2+ in the medium, this was followed by a slow increase in [Ca2+] culminating in a substantial Ca2+ spike representing synchronous discharge from the InsP3-sensitive stores. 3. During the latency preceding the Ca2+ spike, the stores increased their sensitivity to InsP3. This sensitization seemed to be an all-or-none phenomenon. 4. Oxidized glutathione and thimerosal promoted the spontaneous release by sensitizing the InsP3 receptor. 5. An increase in the [Ca2+] within the stores was required for both the increased sensitivity to InsP3 and the subsequent spike. 6. Caffeine (6 mM) antagonized the effect of very low InsP3 concentrations and abolished the Ca2+ spike, without itself releasing Ca2+. 7. Our results suggesting that luminal Ca2+ may sensitive InsP3-sensitive stores leading to spontaneous Ca2+ mobilization will be discussed in the light of a modified version of the two-pool model for explaining cytosolic Ca2+ oscillations. PMID:1484365

  18. New technique for prostatectomy using Ho:YAG laser

    NASA Astrophysics Data System (ADS)

    Daidoh, Yuichiro; Arai, Tsunenori; Murai, Masaru; Nakajima, Akio; Tsuji, Akira; Odajima, Kunio; Nakajima, Fumio; Kikuchi, Makoto; Nakamura, Hiroshi

    1994-05-01

    To develop a new transperineal laser prostatectomy through a biopsy needle, we determined the efficiency of a pulsed Nd:YAG laser irradiation for canine prostate. The Ho:YAG laser ((lambda) equals 2.1 micrometers ) may induced stress-wave to destroy the small vessels in prostate. After the exposure of the canine prostate, it was punctured by the needle. A quartz fiber of which core-diameter was 200 or 400 micrometers was inserted into the 18 G needle. The irradiation fluence was set to 150 - 600 J/cm2 and repetition rate was kept at 2 Hz. The cross-section of the irradiated portion of the prostate extracted immediately after the irradiation showed dark-colored hemorrhage layer around the ablation tract with 1 - 2 mm thickness. Some hemorrhage was histologically seen in stoma and gland in the irradiated prostate. In the case of 150 - 175 J/cm2 in the irradiation fluence, the irradiated portion of the prostate was found in the wedge-shaped area with brown color at one week after the irradiation. The lymphocytes infiltrating into the wedge-shaped zone were found. The wedge- shaped zone spread over the prostate and the change of urethral mucosa was minimum at one month after the irradiation. In the case of 500 - 600 J/cm2 irradiation, the paraurethral cavity was made at one month after the irradiation. The histological examination showed that the hemorrhage and subsequent histological changes may be caused by the laser induced stress-wave rather than thermal effect. Our results suggest that transperineal irradiation of pulsed Ho:YAG might offer an effective treatment for benign prostatic hyperplasia with the minimal damage to the urethral mucosa.

  19. Sporadic Creutzfeldt-Jakob Disease MM1+2C and MM1 are Identical in Transmission Properties.

    PubMed

    Kobayashi, Atsushi; Matsuura, Yuichi; Iwaki, Toru; Iwasaki, Yasushi; Yoshida, Mari; Takahashi, Hitoshi; Murayama, Shigeo; Takao, Masaki; Kato, Shinsuke; Yamada, Masahito; Mohri, Shirou; Kitamoto, Tetsuyuki

    2016-01-01

    The genotype (methionine, M or valine, V) at polymorphic codon 129 of the PRNP gene and the type (1 or 2) of abnormal prion protein in the brain are the major determinants of the clinicopathological features of sporadic Creutzfeldt-Jakob disease (CJD), thus providing molecular basis for classification of sporadic CJD, that is, MM1, MM2, MV1, MV2, VV1 or VV2. In addition to these "pure" cases, "mixed" cases presenting mixed neuropathological and biochemical features have also been recognized. The most frequently observed mixed form is the co-occurrence of MM1 and MM2, namely MM1+2. However, it has remained elusive whether MM1+2 could be a causative origin of dura mater graft-associated CJD (dCJD), one of the largest subgroups of iatrogenic CJD. To test this possibility, we performed transmission experiments of MM1+2 prions and a systematic neuropathological examination of dCJD patients in the present study. The transmission properties of the MM1+2 prions were identical to those of MM1 prions because MM2 prions lacked transmissibility. In addition, the neuropathological characteristics of MM2 were totally absent in dCJD patients examined. These results suggest that MM1+2 can be a causative origin of dCJD and causes neuropathological phenotype similar to that of MM1. PMID:25851836

  20. HO-1/CO system in tumor growth, angiogenesis and metabolism - Targeting HO-1 as an anti-tumor therapy.

    PubMed

    Loboda, Agnieszka; Jozkowicz, Alicja; Dulak, Jozef

    2015-11-01

    Heme oxygenase-1 (HO-1, hmox-1) catalyzes the rate-limiting step in the heme degradation processes. Out of three by-products of HO-1 activity, biliverdin, iron ions and carbon monoxide (CO), the latter was mostly shown to mediate many beneficial HO-1 effects, including protection against oxidative injury, regulation of apoptosis, modulation of inflammation as well as contribution to angiogenesis. Mounting evidence suggests that HO-1/CO systemmay be of special benefit in protection inmany pathological conditions, like atherosclerosis or myocardial infarction. By contrast, the augmented expression of HO-1 in tumor tissues may have detrimental effect as HO-1 accelerates the formation of tumor neovasculature and provides the selective advantage for tumor cells to overcome the increased oxidative stress during tumorigenesis and during treatment. The inhibition of HO-1 has been proposed as an anti-cancer therapy, however, because of non-specific effects of known HO-1 inhibitors, the discovery of ideal drug lowering HO-1 expression/activity is still an open question. Importantly, in several types of cancer HO-1/CO system exerts opposite activities, making the possible treatment more complicated. All together indicates the complex role for HO-1/CO in various in vitro and in vivo conditions. PMID:26392237

  1. Role of Ca++ in Shoot Gravitropism. [avena

    NASA Technical Reports Server (NTRS)

    Rayle, D. L.

    1985-01-01

    A cornerstone in the argument that Ca(2+) levels may regulate growth is the finding the EGTA promotes straight growth. The usual explanation for these results is that Ca(2+) chelation from cell walls results in wall loosening and thus accelerated straight growth. The ability of frozen-thawed Avena coleoptile tissue (subjected to 15g tension) to extend in response to EGTA and Quin II was examined. The EGTA when applied in weakly buffered (i.e., 0.1mM) neutral solutions initiates rapid extension. When the buffer strength is increased, similar concentrations of EGTA produce no growth response. This implies when EGTA liberated protons are released upon Ca(2+) chelation they can either initiate acid growth (low buffer conditions) or if consumed (high buffer conditions) have no effect. Thus Ca(2+) chelation in itself apparently does not result in straight growth.

  2. Vacuolar Ca(2+) uptake.

    PubMed

    Pittman, Jon K

    2011-08-01

    Calcium transporters that mediate the removal of Ca(2+) from the cytosol and into internal stores provide a critical role in regulating Ca(2+) signals following stimulus induction and in preventing calcium toxicity. The vacuole is a major calcium store in many organisms, particularly plants and fungi. Two main pathways facilitate the accumulation of Ca(2+) into vacuoles, Ca(2+)-ATPases and Ca(2+)/H(+) exchangers. Here I review the biochemical and regulatory features of these transporters that have been characterised in yeast and plants. These Ca(2+) transport mechanisms are compared with those being identified from other vacuolated organisms including algae and protozoa. Studies suggest that Ca(2+) uptake into vacuoles and other related acidic Ca(2+) stores occurs by conserved mechanisms which developed early in evolution. PMID:21310481

  3. Substantial depletion of the intracellular Ca2+ stores is required for macroscopic activation of the Ca2+ release-activated Ca2+ current in rat basophilic leukaemia cells.

    PubMed

    Fierro, L; Parekh, A B

    2000-01-15

    1. Tight-seal whole-cell patch clamp experiments were performed to examine the ability of different intracellular Ca2+ mobilising agents to activate the Ca2+ release-activated Ca2+ current (ICRAC) in rat basophilic leukaemia (RBL-1) cells under conditions of weak cytoplasmic Ca2+ buffering. 2. Dialysis with a maximal concentration of inositol 1,4,5-trisphosphate (IP3) routinely failed to activate macroscopic ICRAC in low buffer (0.mM EGTA, BAPTA or dimethyl BAPTA), whereas it activated the current to its maximal extent in high buffer (10 mM EGTA). Dialysis with a poorly metabolisable analogue of IP3, with ionomycin, or with IP3 and ionomycin all failed to generate macroscopic ICRAC in low Ca2+ buffering conditions. 3. Dialysis with the sarco/endoplasmic reticulum Ca2+-ATPase (SERCA) pump blocker thapsigargin was able to activate ICRAC even in the presence of low cytoplasmic Ca2+ buffering, albeit at a slow rate. Exposure to IP3 together with the SERCA blockers thapsigargin, thapsigargicin or cyclopiazonic acid rapidly activated ICRAC in low buffer. 4. Following activation of ICRAC by intracellular dialysis with IP3 and thapsigargin in low buffer, the current was very selective for Ca2+ (apparent KD of 1 mM) Sr2+ and Ba2+ were less effective charge carriers and Na+ was not conducted to any appreciable extent. The ionic selectivity of ICRAC was very similar in low or high intracellular Ca2+ buffer. 5. Fast Ca2+-dependent inactivation of ICRAC occurred at a similar rate and to a similar extent in low or high Ca2+ buffer. Ca2+-dependent inactivation is not the reason why macroscopic ICRAC cannot be seen under conditions of low cytoplasmic Ca2+ buffering. 6. ICRAC could be activated by combining IP3 with thapsigargin, even in the presence of 100 microM Ca2+ and the absence of any exogenous Ca2+ chelator, where ATP and glutamate represented the only Ca2+ buffers in the pipette solution. 7. Our results suggest that a threshold exists within the IP3-sensitive Ca2+ store

  4. 40 CFR Table Mm-2 to Subpart Mm of... - Default Factors for Biomass-Based Fuels and Biomass

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 22 2012-07-01 2012-07-01 false Default Factors for Biomass-Based Fuels and Biomass MM Table MM-2 to Subpart MM of Part 98 Protection of Environment ENVIRONMENTAL... Biomass-Based Fuels and Biomass Biomass-based fuel and biomass Column A:Density (metric tons/bbl) Column...

  5. 40 CFR Table Mm-2 to Subpart Mm of... - Default Factors for Biomass-Based Fuels and Biomass

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 22 2013-07-01 2013-07-01 false Default Factors for Biomass-Based Fuels and Biomass MM Table MM-2 to Subpart MM of Part 98 Protection of Environment ENVIRONMENTAL... Biomass-Based Fuels and Biomass Biomass-based fuel and biomass Column A:Density (metric tons/bbl) Column...

  6. 40 CFR Table Mm-2 to Subpart Mm of... - Default Factors for Biomass-Based Fuels and Biomass

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 21 2014-07-01 2014-07-01 false Default Factors for Biomass-Based Fuels and Biomass MM Table MM-2 to Subpart MM of Part 98 Protection of Environment ENVIRONMENTAL... Biomass-Based Fuels and Biomass Biomass-based fuel and biomass Column A:Density (metric tons/bbl) Column...

  7. 40 CFR Table Mm-1 to Subpart Mm of... - Default Factors for Petroleum Products and Natural Gas Liquids 1 2

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... and Natural Gas Liquids 1 2 MM Table MM-1 to Subpart MM of Part 98 Protection of Environment... Factors for Petroleum Products and Natural Gas Liquids 1 2 Products Column A: density(metric tons/bbl... Natural Gas Liquids Aviation Gasoline 0.1120 85.00 0.3490 Special Naphthas 0.1222 84.76 0.3798...

  8. 40 CFR Table Mm-1 to Subpart Mm of... - Default Factors for Petroleum Products and Natural Gas Liquids 1 2

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... and Natural Gas Liquids 1 2 MM Table MM-1 to Subpart MM of Part 98 Protection of Environment... Factors for Petroleum Products and Natural Gas Liquids 1 2 Products Column A: density(metric tons/bbl... Natural Gas Liquids Aviation Gasoline 0.1120 85.00 0.3490 Special Naphthas 0.1222 84.76 0.3798...

  9. 40 CFR Table Mm-1 to Subpart Mm of... - Default Factors for Petroleum Products and Natural Gas Liquids 1 2

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... and Natural Gas Liquids 1 2 MM Table MM-1 to Subpart MM of Part 98 Protection of Environment... Factors for Petroleum Products and Natural Gas Liquids 1 2 Products Column A: density(metric tons/bbl... Natural Gas Liquids Aviation Gasoline 0.1120 85.00 0.3490 Special Naphthas 0.1222 84.76 0.3798...

  10. 40 CFR Table Mm-1 to Subpart Mm of... - Default Factors for Petroleum Products and Natural Gas Liquids 1 2

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... and Natural Gas Liquids 1 2 MM Table MM-1 to Subpart MM of Part 98 Protection of Environment... Factors for Petroleum Products and Natural Gas Liquids 1 2 Products Column A: density(metric tons/bbl... Natural Gas Liquids Aviation Gasoline 0.1120 85.00 0.3490 Special Naphthas 0.1222 84.76 0.3798...

  11. A λ = 1.3 mm and 2 mm molecular line survey towards M 82

    NASA Astrophysics Data System (ADS)

    Aladro, R.; Martín, S.; Martín-Pintado, J.; Mauersberger, R.; Henkel, C.; Ocaña Flaquer, B.; Amo-Baladrón, M. A.

    2011-11-01

    Aims: We study the chemical complexity towards the central parts of the starburst galaxy M 82, and investigate the role of certain molecules as tracers of the physical processes in the galaxy circumnuclear region. Methods: We carried out a spectral line survey with the IRAM-30 m telescope towards the northeastern molecular lobe of M 82. It covers the frequency range between 129.8 GHz and 175.0 GHz in the 2 mm atmospheric window, and between 241.0 GHz and 260.0 GHz in the 1.3 mm atmospheric window. Results: Sixty-nine spectral features corresponding to 18 different molecular species are identified. In addition, three hydrogen recombination lines are detected. The species NO, H2S, H2CS, NH2CN, and CH3CN are detected for the first time in this galaxy. Assuming local thermodynamic equilibrium, we determine the column densities of all the detected molecules. We also calculate upper limits to the column densities of fourteen other important, but undetected, molecules, such as SiO, HNCO, or OCS. We compare the chemical composition of the two starburst galaxies M 82 and NGC 253. This comparison enables us to establish the chemical differences between the products of the strong photon-dominated regions driving the heating in M 82, and the large-scale shocks that influence the properties of the molecular clouds in the nucleus of NGC 253. Conclusions: Overall, both sources have different chemical compositions. Some key molecules highlight the different physical processes dominating both central regions. Examples include CH3CCH, c-C3H2, or CO+, the abundances of which are clearly higher in M 82 than in NGC 253, pointing at photodissociating regions. On the other hand, species such as CH2NH, NS, SiO, and HOCO+ have abundances of up to one order of magnitude higher in NGC 253 than in M 82. Appendix is available in electronic form at http://www.aanda.org

  12. Role of sarcomere mechanics and Ca2+ overload in Ca2+ waves and arrhythmias in rat cardiac muscle.

    PubMed

    ter Keurs, Henk E D J; Wakayama, Yuji; Sugai, Yoshinao; Price, Guy; Kagaya, Yutaka; Boyden, Penelope A; Miura, Masahito; Stuyvers, Bruno D M

    2006-10-01

    Ca(2+) release from the sarcoplasmic reticulum (SR) depends on the sarcoplasmic reticulum (SR) Ca(2+) load and the cytosolic Ca(2+) level. Arrhythmogenic Ca(2+) waves underlying triggered propagated contractions arise from Ca(2+) overloaded regions near damaged areas in the cardiac muscle. Ca(2+) waves can also be induced in undamaged muscle, in regions with nonuniform excitation-contraction (EC) coupling by the cycle of stretch and release in the border zone between the damaged and intact regions. We hypothesize that rapid shortening of sarcomeres in the border zone during relaxation causes Ca(2+) release from troponin C (TnC) on thin filaments and initiates Ca(2+) waves. Elimination of this shortening will inhibit the initiation of Ca(2+) waves, while SR Ca(2+) overload will enhance the waves. Force, sarcomere length (SL), and [Ca(2+)](i) were measured and muscle length was controlled. A small jet of Hepes solution with an extracellular [Ca(2+)] 10 mM (HC), or HC containing BDM, was used to weaken a 300 mum long muscle segment. Trains of electrical stimuli were used to induce Ca(2+) waves. The effects of small exponential stretches on triggered propagatory contraction (TPC) amplitude and propagation velocity of Ca(2+) waves (V(prop)) were studied. Sarcomere shortening was uniform prior to activation. HC induced spontaneous diastolic sarcomere contractions in the jet region and attenuated twitch sarcomere shortening; HC+ butanedione monoxime (BDM) caused stretch only in the jet region. Stimulus trains induced Ca(2+) waves, which started inside the HC jet region during twitch relaxation. Ca(2+) waves started in the border zone of the BDM jet. The initial local [Ca(2+)](i) rise of the waves by HC was twice that by BDM. The waves propagated at a V(prop) of 2.0 +/- 0.2 mm/sec. Arrhythmias occurred frequently in trabeculae following exposure to the HC jet. Stretch early during relaxation, which reduced sarcomere shortening in the weakened regions, substantially

  13. Dual Effect of Phosphate Transport on Mitochondrial Ca2+ Dynamics*

    PubMed Central

    Wei, An-Chi; Liu, Ting; O'Rourke, Brian

    2015-01-01

    The large inner membrane electrochemical driving force and restricted volume of the matrix confer unique constraints on mitochondrial ion transport. Cation uptake along with anion and water movement induces swelling if not compensated by other processes. For mitochondrial Ca2+ uptake, these include activation of countertransporters (Na+/Ca2+ exchanger and Na+/H+ exchanger) coupled to the proton gradient, ultimately maintained by the proton pumps of the respiratory chain, and Ca2+ binding to matrix buffers. Inorganic phosphate (Pi) is known to affect both the Ca2+ uptake rate and the buffering reaction, but the role of anion transport in determining mitochondrial Ca2+ dynamics is poorly understood. Here we simultaneously monitor extra- and intra-mitochondrial Ca2+ and mitochondrial membrane potential (ΔΨm) to examine the effects of anion transport on mitochondrial Ca2+ flux and buffering in Pi-depleted guinea pig cardiac mitochondria. Mitochondrial Ca2+ uptake proceeded slowly in the absence of Pi but matrix free Ca2+ ([Ca2+]mito) still rose to ∼50 μm. Pi (0.001–1 mm) accelerated Ca2+ uptake but decreased [Ca2+]mito by almost 50% while restoring ΔΨm. Pi-dependent effects on Ca2+ were blocked by inhibiting the phosphate carrier. Mitochondrial Ca2+ uptake rate was also increased by vanadate (Vi), acetate, ATP, or a non-hydrolyzable ATP analog (AMP-PNP), with differential effects on matrix Ca2+ buffering and ΔΨm recovery. Interestingly, ATP or AMP-PNP prevented the effects of Pi on Ca2+ uptake. The results show that anion transport imposes an upper limit on mitochondrial Ca2+ uptake and modifies the [Ca2+]mito response in a complex manner. PMID:25963147

  14. Ramipril protects the endothelium from high glucose-induced dysfunction through CaMKKβ/AMPK and heme oxygenase-1 activation.

    PubMed

    Tian, Shiliu; Ge, Xinfa; Wu, Ke; Yang, Huabing; Liu, Yu

    2014-07-01

    This study aims to investigate the effects of ramipril (RPL) on endothelial dysfunction associated with diabetes mellitus using cultured human aortic endothelial cells (HAECs) and a type 2 diabetic animal model. The effect of RPL on vasodilatory function in fat-fed, streptozotocin-treated rats was assessed. RPL treatment of 8 weeks alleviated insulin resistance and inhibited the decrease in endothelium-dependent vasodilation in diabetic rats. RPL treatment also reduced serum advanced glycation end products (AGE) concentration and rat aorta reactive oxygen species formation and increased aorta endothelium heme oxygenase-1 (HO-1) expression. Exposure of HAECs to high concentrations of glucose induced prolonged oxidative stress, apoptosis, and accumulation of AGEs. These effects were abolished by incubation of ramiprilat (RPT), the active metabolite of RPL. However, treatment of HAECs with STO-609, a CaMKKβ (Ca(2+)/calmodulin-dependent protein kinase kinase-β) inhibitor; compound C, an AMPK (AMP-activated protein kinase) inhibitor; and Zn(II)PPIX, a selective HO-1 inhibitor, blocked these beneficial effects of RPT. In addition, RPT increased nuclear factor erythroid 2-related factor-2 (Nrf-2) nuclear translocation and activation in a CaMKKβ/AMPK pathway-dependent manner, leading to increased expression of the Nrf-2-regulated antioxidant enzyme, HO-1. The inhibition of CaMKKβ or AMPK by pharmaceutical approach ablated RPT-induced HO-1 expression. Taken together, RPL ameliorates insulin resistance and endothelial dysfunction in diabetes via reducing oxidative stress. These effects are mediated by RPL activation of CaMKK-β, which in turn activates the AMPK-Nrf-2-HO-1 pathway for enhanced endothelial function. PMID:24741076

  15. T-type Ca2+ channels mediate propagation of odor-induced Ca2+ transients in rat olfactory receptor neurons.

    PubMed

    Gautam, S H; Otsuguro, K-I; Ito, S; Saito, T; Habara, Y

    2007-01-19

    Propagation of odor-induced Ca(2+) transients from the cilia/knob to the soma in mammalian olfactory receptor neurons (ORNs) is thought to be mediated exclusively by high-voltage-activated Ca(2+) channels. However, using confocal Ca(2+) imaging and immunocytochemistry we identified functional T-type Ca(2+) channels in rat ORNs. Here we show that T-type Ca(2+) channels in ORNs also mediate propagation of odor-induced Ca(2+) transients from the knob to the soma. In the presence of the selective inhibitor of T-type Ca(2+) channels mibefradil (10-15 microM) or Ni(2+) (100 microM), odor- and forskolin/3-isobutyl-1-methyl-xanthine (IBMX)-induced Ca(2+) transients in the soma and dendrite were either strongly inhibited or abolished. The percentage of inhibition of the Ca(2+) transients in the knob, however, was 40-50% less than that in the soma. Ca(2+) transients induced by 30 mM K(+) were partially inhibited by mibefradil, but without a significant difference in the extent of inhibition between the knob and soma. Furthermore, an increase of as little as 2.5 mM in the extracellular K(+) concentration (7.5 mM K(+)) was found to induce Ca(2+) transients in ORNs, and such responses were completely inhibited by mibefradil or Ni(2+). Total replacement of extracellular Na(+) with N-methyl-d-glutamate inhibited none of the odor-, forskolin/IBMX- or 7.5 mM K(+)-induced Ca(2+) transients. Positive immunoreactivity to the Ca(v)3.1, Ca(v)3.2 and Ca(v)3.3 subunits of the T-type Ca(2+) channel was observed throughout the soma, dendrite and knob. These data suggest that involvement of T-type Ca(2+) channels in the propagation of odor-induced Ca(2+) transients in ORNs may contribute to signal transduction and odor sensitivity. PMID:17110049

  16. Effects of cytosolic ATP on spontaneous and triggered Ca2+-induced Ca2+ release in permeabilised rat ventricular myocytes.

    PubMed

    Yang, Z; Steele, D S

    2000-02-15

    1. The effects of cytosolic ATP on sarcoplasmic reticulum (SR) Ca2+ regulation were investigated in saponin-permeabilised rat ventricular myocytes. [Ca2+] within the cells was monitored using Fura-2 or Fluo-3 fluorescence. Spontaneous cyclic Ca2+ release from the SR was induced by increasing the bathing [Ca2+] to 200-300 nM, in solutions weakly Ca2+ buffered with 0.05 mM EGTA. Alternatively, Ca2+-induced Ca2+ release (CICR) was triggered by a rapid increase in [Ca2+] induced by flash photolysis of Nitr-5 (0.08 mM), replacing EGTA in the solution. 2. Stepwise reductions in [ATP] were associated with corresponding decreases in the frequency and increases in the amplitude of spontaneous Ca2+ transients. A decrease from 5 mM to 0. 1 mM ATP, reduced the release frequency by 48.6 +/- 7 % (n = 7) and almost doubled the amplitude of the Ca2+ transient. Marked prolongation of the spontaneous Ca2+ transient occurred when [ATP] was further reduced to 10 microM, consistent with inhibition of the SR Ca2+ pump. 3. These effects of ATP were compared with other interventions that inhibit Ca2+ uptake or reduce the sensitivity of the SR Ca2+ release mechanism. Inhibition of the SR Ca2+ pump with cyclopiazonic acid (CPA) markedly reduced the spontaneous Ca2+ release frequency, without changing the amplitude. The descending phase of the Ca2+ transient was prolonged in the presence of CPA, while the rising phase was unaffected. In contrast, desensitisation of the SR Ca2+ release mechanism with tetracaine decreased the frequency of spontaneous release, but markedly increased the amplitude. 4. CICR triggered by flash photolysis of Nitr-5 appeared to be more sensitive to cytosolic [ATP] than spontaneous release and was generally delayed by a decrease to 2.5 mM ATP. In the presence of 0.1-0.2 mM ATP, release often failed completely or was not consistently triggered. Some preparations exhibited Ca2+ release 'alternans', whereby every alternate trigger induced a response. 5. These results

  17. Osmotically induced cytosolic free Ca(2+) changes in human neutrophils.

    PubMed

    Morris, M R; Doull, I J; Hallett, M B

    2001-02-01

    Cytosolic free Ca(2+) concentration in neutrophils was measured by ratiometric fluorometry of intracellular fura2. Increasing the extracellular osmolarity, by either NaCl (300-600 mM) or sucrose (600-1200 mM), caused a rise in cytosolic free Ca(2+) (Delta(max) approximately equal to 600 nM). This was not due to cell lysis as the cytosolic free Ca(2+) concentration was reversed by restoration of isotonicity and a second rise in cytosolic free Ca(2+) could be provoked by repeating the change in extracellular osmolarity. Furthermore, the rise in cytosolic free Ca(2+) concentration occurred in the absence of extracellular Ca(2+), demonstrating that release of intracellular fura2 into the external medium did not occur. The osmotically-induced rise in cytosolic free Ca(2+) was not inhibited by either the phospholipase C-inhibitor U73122, or the microfilament inhibitor cytochalasin B, suggesting that neither signalling via inositol tris-phosphate or the cytoskeletal system were involved. However, the rise in cytosolic free Ca(2+) may have resulted from a reduction in neutrophil water volume in hyperosmotic conditions. As these rises in cytosolic Ca(2+) (Delta(max) approximately equal to 600 nM) were large enough to provoke changes in neutrophil activity, we propose that conditions which removes cell water may similarly elevate cytosolic free Ca(2+) to physiologically important levels. PMID:11341979

  18. A λ 3 mm and 1 mm line survey toward the yellow hypergiant IRC +10420⋆

    PubMed Central

    Quintana-Lacaci, G.; Agúndez, M.; Cernicharo, J.; Bujarrabal, V.; Sánchez Contreras, C.; Castro-Carrizo, A.; Alcolea, J.

    2016-01-01

    Aims Our knowledge of the chemical properties of the circumstellar ejecta of the most massive evolved stars is particularly poor. We aim to study the chemical characteristics of the prototypical yellow hypergiant star, IRC +10420. For this purpose, we obtained full line surveys at 1 and 3 mm atmospheric windows. Methods We have identified 106 molecular emission lines from 22 molecular species. Approximately half of the molecules detected are N-bearing species, in particular HCN, HNC, CN, NO, NS, PN, and N2H+. We used rotational diagrams to derive the density and rotational temperature of the different molecular species detected. We introduced an iterative method that allows us to take moderate line opacities into account. Results We have found that IRC +10420 presents high abundances of the N-bearing molecules compared with O-rich evolved stars. This result supports the presence of a N-rich chemistry, expected for massive stars. Our analysis also suggests a decrease of the 12C/13C ratio from ≳ 7 to ~ 3.7 in the last 3800 years, which can be directly related to the nitrogen enrichment observed. In addition, we found that SiO emission presents a significant intensity decrease for high-J lines when compared with older observations. Radiative transfer modeling shows that this variation can be explained by a decrease in the infrared (IR) flux of the dust. The origin of this decrease might be an expansion of the dust shell or a lower stellar temperature due to the pulsation of the star. PMID:27458319

  19. Efficacy and safety of Ho:YAG Laser Lithotripsy for ureteroscopic removal of proximal and distal ureteral calculi

    PubMed Central

    2014-01-01

    Background Laser lithotripsy is an established endourological modality. Ho:YAG laser have broadened the indications for ureteroscopic stone managements to include larger stone sizes throughout the whole upper urinary tract. Aim of current work is to assess efficacy and safety of Ho:YAG laser lithotripsy during retrograde ureteroscopic management of ureteral calculi in different locations. Methods 88 patients were treated with ureteroscopic Ho:YAG laser lithotripsy in our institute. Study endpoint was the number of treatments until the patient was stone-free. Patients were classified according to the location of their stones as Group I (distal ureteric stones, 51 patients) and group II (proximal ureteral stones, 37). Group I patients have larger stones as Group II (10.70 mm vs. 8.24 mm, respectively, P = 0.020). Results Overall stone free rate for both groups was 95.8%. The mean number of procedures for proximal calculi was 1.1 ± 0.1 (1–3) and for distal calculi was 1.0 ± 0.0. The initial treatment was more successful in patients with distal ureteral calculi (100% vs. 82.40%, respectively, P = 0.008). No significant difference in the stone free rate was noticed after the second laser procedure for stones smaller versus larger than 10 mm (100% versus 94.1%, P = 0.13). Overall complication rate was 7.9% (Clavien II und IIIb). Overall and grade-adjusted complication rates were not dependant on the stone location. No laser induced complications were noticed. Conclusions The use of the Ho:YAG laser appears to be an adequate tool to disintegrate ureteral calculi independent of primary location. Combination of the semirigid and flexible ureteroscopes as well as the appropriate endourologic tools could likely improve the stone clearance rates for proximal calculi regardless of stone-size. PMID:25107528

  20. High Energy Directly Pumped Ho:YLF Laser

    NASA Technical Reports Server (NTRS)

    Petros, Mulugeta; Yu, Ji-Rong; Singh, Upendra N.; Barnes, Norman P.

    2000-01-01

    The most commonly used crystal architecture to produce 2 micrometer laser is co-doping Ho and Tm into a single host crystal. In this method, the stored energy transfer from the Tm (3)F4 to the Ho (5)I7 manifold is not fast enough to warrant high efficiency for short pulse applications. By separating the Ho and the Tm ions and doping the Tm in YALO3 and the Ho in YLF, we were able to directly pump the Ho (5)I7 manifold with 1.94 micrometers. The Ho:YLF laser has produced 33 mJ at 2.062 micrometers with a quantum efficiency of 0.88. The performance of each laser will be presented.

  1. Activation of the Nrf2/HO-1 Antioxidant Pathway Contributes to the Protective Effects of Lycium Barbarum Polysaccharides in the Rodent Retina after Ischemia-Reperfusion-Induced Damage

    PubMed Central

    Chang, Raymond Chuen-Chung; So, Kwok-Fai; Brecha, Nicholas C.; Pu, Mingliang

    2014-01-01

    Lycium barbarum polysaccharides (LBP), extracts from the wolfberries, are protective to retina after ischemia-reperfusion (I/R). The antioxidant response element (ARE)–mediated antioxidant pathway plays an important role in maintaining the redox status of the retina. Heme oxygenase-1 (HO-1), combined with potent AREs in its promoter, is a highly effective therapeutic target for the protection against neurodegenerative diseases, including I/R-induced retinal damage. The aim of our present study was to investigate whether the protective effect of LBP after I/R damage was mediated via activation of the Nrf2/HO-1-antioxidant pathway in the retina. Retinal I/R was induced by an increase in intraocular pressure to 130 mm Hg for 60 minutes. Prior to the induction of ischemia, rats were orally treated with either vehicle (PBS) or LBP (1 mg/kg) once a day for 1 week. For specific experiments, zinc protoporphyrin (ZnPP, 20 mg/kg), an HO-1 inhibitor, was intraperitoneally administered at 24 h prior to ischemia. The protective effects of LBP were evaluated by quantifying ganglion cell and amacrine cell survival, and by measuring cell apoptosis in the retinal layers. In addition, HO-1 expression was examined using Western blotting and immunofluorescence analyses. Cytosolic and nuclear Nrf2 was measured using immunofluorescent staining. LBP treatment significantly increased Nrf2 nuclear accumulation and HO-1 expression in the retina after I/R injury. Increased apoptosis and a decrease in the number of viable cells were observed in the ganglion cell layer (GCL) and inner nuclear layer (INL) in the I/R retina, which were reversed by LBP treatment. The HO-1 inhibitor, ZnPP, diminished the LBP treatment-induced protective effects in the retina after I/R. Taken together, these results suggested that LBP partially exerted its beneficial neuroprotective effects via the activation of Nrf2 and an increase in HO-1 protein expression. PMID:24400114

  2. Ca channel gating during cardiac action potentials.

    PubMed

    Mazzanti, M; DeFelice, L J

    1990-10-01

    How do Ca channels conduct Ca ions during the cardiac action potential? We attempt to answer this question by applying a two-microelectrode technique, previously used for Na and K currents, in which we record the patch current and the action potential at the same time (Mazzanti, M., and L. J. DeFelice. 1987. Biophys. J. 12:95-100, and 1988. Biophys. J. 54:1139-1148; Wellis, D., L. J. DeFelice, and M. Mazzanti. 1990. Biophys. J. 57:41-48). In this paper, we also compare the action currents obtained by the technique with the step-protocol currents obtained during standard voltage-clamp experiments. Individual Ca channels were measured in 10 mM Ca/1 Ba and 10 mM Ba. To describe part of our results, we use the nomenclature introduced by Hess, P., J. B. Lansman, and R. W. Tsien (1984. Nature (Lond.). 311:538-544). With Ba as the charge carrier, Ca channel kinetics convert rapidly from long to short open times as the patch voltage changes from 20 to -20 mV. This voltage-dependent conversion occurs during action potentials and in step-protocol experiments. With Ca as the charge carrier, the currents are brief at all voltages, and it is difficult to define either the number of channels in the patch or the conductance of the individual channels. Occasionally, however, Ca-conducting channels spontaneously convert to long-open-time kinetics (in Hess et al., 1984, notation, mode 2). When this happens, which is about once in every 100beats, there usually appears to be only one channel in the patch. In this rare configuration, the channel is open long enough to measure its conductance in 10 Ca/ 1 Ba. The value is 8-10 pS, which is about half the conductance in Ba. Because the long openings occur so infrequently with Ca as the charge carrier, they contribute negligibly to the average Ca current at any particular time during an action potential. However, the total number of Ca ions entering during these long openings may be significant when compared to the number entering by the

  3. Spectroscopic and lasing properties of Ho:Tm:LuAG

    NASA Technical Reports Server (NTRS)

    Barnes, Norman P.; Filer, Elizabeth D.; Naranjo, Felipe L.; Rodriguez, Waldo J.; Kokta, Milan R.

    1993-01-01

    Ho:Tm:LuAG has been grown, examined spectroscopically, and lased at 2.1 microns. Ho:Tm:LuAG was selected for this experimental investigation when quantum-mechanical modeling predicted that it would be a good laser material for Ho laser operation on one of the 5I7 to 5I8 transitions. Lasing was achieved at 2.100 microns, one of the three wavelengths predicted to be most probable for laser action.

  4. Rotational bands in neutron-rich 160-162Ho

    SciTech Connect

    Escrig, D.; Jungclaus, A.; Binder, B.; Dietrich, A.; Haertlein, T.; Bauer, H.; Gund, Ch.; Pansegrau, D.; Schwalm, D.; Bazzacco, D.; De Angelis, G.; Farnea, E.; Gadea, A.; Lunardi, S.; Napoli, D.R.; Rossi-Alvarez, C.; Ur, C.

    2004-02-27

    We have studied the high spin states in 160-162Ho in order to investigate the properties of the rotational bands and their dependence on the single particle orbits involved. The reaction 158,160Gd(7Li,xn) at 56 MeV were used to produce the Ho isotopes of interest. In all three Ho isotopes the known rotational bands have been significantly extended. New band-crossings have been observed for the first time in this work.

  5. 2. West portal of Tunnel 37 view to eastsoutheast, 135mm ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. West portal of Tunnel 37 view to east-southeast, 135mm lens. Note the notched wingwalls that would have originally held timber posts of the original timber snowsheds, miles of which once enclosed and protected the railroad from the ravages of Sierra winters. Note also that these tunnels, built in the 1920s, have dispensed with any use of stone masonry, and instead have all-concrete portals, though this tunnel retains the use of rubble granite slab slope protection flanking the portal. - Central Pacific Transcontinental Railroad, Tunnel No. 37, Milepost 177.79, Yuba Pass, Nevada County, CA

  6. 2. West portal of Tunnel 38, view to east, 135mm ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. West portal of Tunnel 38, view to east, 135mm lens. Note the notched wingwalls that support steel posts of entrance snowshed; these would have originally held timber posts of the original timber snowsheds, miles of which once enclosed and protected the railroad from the ravages of Sierra winters. Note also that these tunnels, built in the 1920s, have dispensed with any use of stone masonry, and instead have all-concrete portals. - Central Pacific Transcontinental Railroad, Tunnel No. 38, Milepost 180.58, Cisco, Placer County, CA

  7. 2. West portal of Tunnel 39, view to east, 135mm ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. West portal of Tunnel 39, view to east, 135mm lens with electronic flash fill. Note the notched wingwalls that support steel posts of entrance snowshed; these would have originally held timber posts of the original timber snowsheds, miles of which once enclosed and protected the railroad from the ravages of Sierra winters. Note also that these tunnels, built in the 1920s, have dispensed with any use of stone masonry, and instead have all-concrete portals. - Central Pacific Transcontinental Railroad, Tunnel No. 39, Milepost 180.95, Cisco, Placer County, CA

  8. 2. West portal of Tunnel 35, view to east, 135mm ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. West portal of Tunnel 35, view to east, 135mm lens with electronic flash fill. Note the notched wingwalls that support steel posts of entrance snowshed; these would have originally held timber posts of the original timber snowsheds, miles of which once enclosed and protected the railroad from the ravages of Sierra winters. Note also that these tunnels, built in the 1920s, have dispensed with any use of stone masonry, and instead have all-concrete portals. - Central Pacific Transcontinental Railroad, Tunnel No. 35, Milepost 176.62, Yuba Pass, Nevada County, CA

  9. 3. West portal of Tunnel 23, view to north, 135mm ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. West portal of Tunnel 23, view to north, 135mm lens. Concrete foundation in right foreground was from 'telltale,' a simple post-and-beam frame that spanned the tracks with lengths of rope suspended from the beam. In the days when brakemen were required to be on, and walk along, the tops of freight cars to set brakes, the 'telltale' ropes would strike the unwary to warn of the tunnel ahead, allowing them to lie flat and avoid being struck by the tunnel portal. - Central Pacific Transcontinental Railroad, Tunnel No. 23, Milepost 132.69, Applegate, Placer County, CA

  10. Reentrant superconductivity in HoNi5-NbN-HoNi5 nanostructures

    NASA Astrophysics Data System (ADS)

    Singh, Gyanendra; Joshi, P. C.; Hossain, Z.; Budhani, R. C.

    2013-08-01

    Superconductivity (S) and ferromagnetism (F) are probed through transport and magnetization measurements in nanometer scale HoNi5-NbN (F-S) bilayers and HoNi5-NbN-HoNi5 (F-S-F) trilayers. The choice of materials has been made on the basis of their comparable ordering temperatures and strong magnetic anisotropy in HoNi5. We observe the normal state reentrant behavior in resistance vs. temperature plots of the F-S-F structures just below the superconducting transition in the limited range of HoNi5 layer thickness dHN (20\\ \\text{nm}) when d_{\\textit{NbN}} is fixed at{}\\simeq 10\\ \\text{nm} . The reentrance is quenched by increasing the out-of-plane (H_{\\perp} ) magnetic field and transport current where as in-plane (H_{\\parallel} ) field of \\leq 1500\\ \\text{Oe} has no effect on the reentrance. The origin of the reentrant behavior seen here in the range T_{\\textit{Curie}}/T_C \\leq 0.92 is attributed to a delicate balance between the magnetic exchange energy and the condensation energy in the interfacial regions of the trilayer.

  11. Is smaller better? Comparison of 3-mm and 5-mm leaf size for stereotactic radiosurgery: A dosimetric study

    SciTech Connect

    Chern, Shyh-shi . E-mail: Richard.Chern@hci.utah.edu; Leavitt, Dennis D.; Jensen, Randy L.; Shrieve, Dennis C.

    2006-11-15

    Purpose: To perform a dosimetric comparison of a minimal 3-mm leaf width multileaf collimator (MLC) and a minimal 5-mm MLC in dynamic conformal arc stereotactic radiosurgery for treatment of intracranial lesions. Methods and Materials: The treatment plans of 23 patients previously treated for intracranial lesions in our institution were redone using the BrainSCAN, version 5.3, stereotactic radiosurgery treatment planning system (BrainLAB). For each case, two dynamic conformal arc plans were generated: one using a minimal 3-mm micro-MLC (BrainLAB, Novalis) and one using a minimal 5-mm MLC (Varian Millennium). All arc parameters were the same in each of the two plans, except for the collimator angle settings. The collimator angle settings were optimized for each arc in each plan. A peritumoral rind structure (1 cm) was created to evaluate normal tissue sparing immediately adjacent to the target volume. Conformity indexes (CIs) were calculated for each plan. The dependence of normal tissue sparing and target conformity on target volume (TV) was determined. Results: The TV was 0.14-36.32 cm{sup 3} (median, 5.90). The CI was 1.22-2.60 (median, 1.51) for the 3-mm micro-MLC and 1.23-2.69 (median, 1.60) for the 5-mm MLC. Despite this small difference, it was a statistically significant increase (p < 0.0001) for the 5-mm MLC compared with the 3-mm micro-MLC. Improved normal tissue sparing was demonstrated using the 3-mm micro-MLC compared with the 5-mm MLC by examining the peritumoral rind volumes (PRVs) receiving 50% (PRV{sub 5}), 80% (PRV{sub 8}), and 90% (PRV{sub 9}) of the prescription dose. The reduction in the PRV{sub 5}, PRV{sub 8}, and PRV{sub 9} for the 3-mm micro-MLC compared with the 5-mm MLC was 13.5%, 12.9%, and 11.5%, respectively. The CI decreased with a larger TV, as did the difference in the CIs between the 3-mm micro-MLC and 5-mm MLC. A reduction in the PRV increased with larger TVs. Conclusion: The 3-mm micro-MLC provided better target conformity and

  12. Index to 8mm Motion Cartridges. Third Edition.

    ERIC Educational Resources Information Center

    University of Southern California, Los Angeles. National Information Center for Educational Media.

    Research at the National Information Center for Educational Media has shown that the 8mm motion cartridge with optical and magnetic sound seems to meet the basic tenets of a prime educational criterion for an educational medium--that it be available to the learner at his convenience. This is a bibliographical source for 8mm motion cartridges, and…

  13. Index to 8mm Motion Cartridges. Fourth Edition.

    ERIC Educational Resources Information Center

    University of Southern California, Los Angeles. National Information Center for Educational Media.

    Research at the National Information Center for Educational Media (NICEM) has shown that the 8mm motion cartridge with optical and magnetic sound seems to meet the basic tenets of a prime educational criterion for an educational medium--that it be available to the learner at his convenience. This is a bibliographical source for 8mm motion…

  14. Do Noncontingent Interviewer Mm-hmms Facilitate Interviewee Productivity?

    ERIC Educational Resources Information Center

    Siegman, Aron Wolfe

    1976-01-01

    Two studies investigated the hypothesis that noncontingent interviewer "mm-hmms" facilitate interviewee verbal productivity. Within- and between-subjects comparisons failed to support the hypothesis, although interviewees' ratings indicate that the mm-hmms were perceived as the social reinforcers they were intended to be. (Author)

  15. Improving Student Understanding of Magmatic Differentiation Using an M&M Magma Chamber

    NASA Astrophysics Data System (ADS)

    Wirth, K. R.

    2003-12-01

    Many students, especially those in introductory geology courses, have difficulty developing a deep understanding of the processes of magmatic differentiation. In particular, students often struggle to understand Bowen's reaction series and fractional crystallization. The process of fractional crystallization by gravity settling can be illustrated using a model magma chamber consisting of M&M's. In this model, each major cation (e.g., Si, Ti, Al, Fe, Mg, Ca, Na, K) is represented by a different color M&M; other kinds of differently colored or shaped pieces could also be used. Appropriate numbers of each color M&M are combined to approximate the cation proportions of a basaltic magma. Students then fractionate the magma by moving M&M's to the bottom of the magma chamber forming a series of cumulus layers; the M&M's are removed in the stoichiometric proportions of cations in the crystallizing minerals (e.g., olivine, pyroxene, feldspars, quartz, magnetite, ilmenite). Students observe the changing cation composition (proportions of colors of M&M's) in the cumulus layers and in the magma chamber and graph the results using spreadsheet software. More advanced students (e.g., petrology course) can classify the cumulates and resulting liquid after each crystallization step, and they can compare the model system with natural magmatic systems (e.g., absence of important fractionating phases, volatiles). Students who have completed this exercise generally indicate a positive experience and demonstrate increased understanding of Bowen's reaction series and fractionation processes. They also exhibit greater familiarity with mineral stoichiometry, classification, solid-solution in minerals, element behavior (e.g., incompatibility), and chemical variation diagrams. Other models (e.g., paths of equilibrium and fractional crystallization on phase diagrams) can also be used to illustrate differentiation processes in upper level courses (e.g., mineralogy and petrology).

  16. Thales Angenieux: 42 years of cine 35 mm zoom leadership

    NASA Astrophysics Data System (ADS)

    Debize, Jacques

    2004-02-01

    Since the early years of zoom optics, Angenieux has been involved in cine 8 mm, 16 mm and 35 mm. Among more than twenty different zoom lenses, four of them have been milestones in this field, technical progresses being sanctified by two Oscars in 1964 and 1990. From 1960 to 2002 Angenieux has created first the 4 x 35 LA2, the first four times mechanically compensated zoom lens for cine 35 mm in the world, secondary the 10 x 25 T2, the first ten times mechanically compensated zoom lens for cine 35 mm in the world, then the 10 x 25 HR, the top level of quality for its category and finally the 12 x 24 Optimo with all characteristics and performances greatly increased. This leadership has been reached thanks to computers and in-house softwares but also thanks to new manufacturing processes.

  17. Ho Doped BixSby Nanopolycrystalline Alloys

    NASA Astrophysics Data System (ADS)

    Lukas, K. C.; Joshi, G.; Wang, Dezhi; Ren, Z. F.; Opeil, C. P.

    2011-03-01

    Department of Physics, Boston College, Chestnut Hill, Massachusetts, 02467. Bismuth-Antimony alloys have been shown to have high ZT values below room temperature, especially for single crystals. For polycrystalline samples, impurity doping and magnetic field have proven to be powerful tools in the search for understanding and improving thermoelectric performance. Nanopolycrystalline BixSby doped with 1 and 3 % Ho were prepared by ball milling and dc hot pressing technique. Electrical resistivity, Seebeck coefficient, thermal conductivity, carrier concentration, mobility, and magnetization are measured in a temperature range of 5-350 K and in magnetic fields up to 9 Tesla. The effects of Ho doping on the thermoelectric properties of BixSby in magnetic field will be discussed. D.O.E. Energy Frontier Research Center Grant (S3TEC), at Massachusetts Institute of Technology.

  18. Hořava-Lifshitz quantum cosmology

    NASA Astrophysics Data System (ADS)

    Bertolami, Orfeu; Zarro, Carlos A. D.

    2011-08-01

    In this work, a minisuperspace model for the projectable Hořava-Lifshitz gravity without the detailed-balance condition is investigated. The Wheeler-DeWitt equation is derived and its solutions are studied and discussed for some particular cases where, due to Hořava-Lifshitz gravity, there is a “potential barrier” nearby a=0. For a vanishing cosmological constant, a normalizable wave function of the Universe is found. When the cosmological constant is nonvanishing, the WKB method is used to obtain solutions for the wave function of the Universe. Using the Hamilton-Jacobi equation, one discusses how the transition from quantum to classical regime occurs and, for the case of a positive cosmological constant, the scale factor is shown to grow exponentially, hence recovering the general relativity behavior for the late Universe.

  19. Low noise, tunable Ho:fiber soliton oscillator for Ho:YLF amplifier seeding

    NASA Astrophysics Data System (ADS)

    Li, Peng; Ruehl, Axel; Bransley, Colleen; Hartl, Ingmar

    2016-06-01

    We present a passively mode-locked, tunable soliton Ho:fiber ring oscillator, optimized for seeding of holmium-doped yttrium lithium flouride (Ho:YLF) amplifiers. The oscillator is independently tunable in central wavelength and spectral width from 2040 to 2070 nm and from 5 to 10 nm, respectively. At all settings the pulse energy within the soliton is around 800 pJ. The soliton oscillator was optimized to fully meet the spectral requirements for seeding Ho:YLF amplifiers. Its Kelly sidebands are located outside the amplifier gain spectrum, resulting in a train of about 1 ps long pedestal-free pulses with relative intensity noise of only 0.13% RMS when integrated from 1 Hz to Nyquist frequency.

  20. Amplitude modulation drive to rectangular-plate linear ultrasonic motors with vibrators dimensions 8 mm x 2.16 mm X 1 mm.

    PubMed

    Ming, Yang; Hanson, Ben; Levesley, Martin C; Walker, Peter G; Watterson, Kevin G

    2006-12-01

    In this paper, to exploit the contribution from not only the stators but also from other parts of miniature ultrasonic motors, an amplitude modulation drive is proposed to drive a miniature linear ultrasonic motor consisting of two rectangular piezoelectric ceramic plates. Using finite-element software, the first longitudinal and second lateral-bending frequencies of the vibrator are shown to be very close when its dimensions are 8 mm x 2.16 mm x 1 mm. So one single frequency power should be able to drive the motor. However, in practice the motor is found to be hard to move with a single frequency power because of its small vibration amplitudes and big frequency difference between its longitudinal and bending resonance, which is induced by the boundary condition variation. To drive the motor effectively, an amplitude modulation drive is used by superimposing two signals with nearly the same frequencies, around the resonant frequency of the vibrators of the linear motor. When the amplitude modulation frequency is close to the resonant frequency of the vibrator's surroundings, experimental results show that the linear motor can move back and forward with a maximum thrust force (over 0.016 N) and a maximum velocity (over 50 mm/s). PMID:17186925

  1. Japanese Science Films; a Descriptive and Evaluative Catalog of: 16mm Motion Pictures, 8mm Cartridges, and Video Tapes.

    ERIC Educational Resources Information Center

    Newren, Edward F., Ed.

    One hundred and eighty Japanese 16mm motion pictures, 8mm cartridges, and video tapes produced and judged appropriate for a variety of audience levels are listed in alphabetical order by title with descriptive and evaluative information. A subject heading list and a subject index to the film titles are included, as well as a sample of the…

  2. Replacing 16 mm film cameras with high definition digital cameras

    SciTech Connect

    Balch, K.S.

    1995-12-31

    For many years 16 mm film cameras have been used in severe environments. These film cameras are used on Hy-G automotive sleds, airborne gun cameras, range tracking and other hazardous environments. The companies and government agencies using these cameras are in need of replacing them with a more cost effective solution. Film-based cameras still produce the best resolving capability, however, film development time, chemical disposal, recurring media cost, and faster digital analysis are factors influencing the desire for a 16 mm film camera replacement. This paper will describe a new camera from Kodak that has been designed to replace 16 mm high speed film cameras.

  3. The 19 mm data recorders similarities and differences

    NASA Technical Reports Server (NTRS)

    Atkinson, Steve

    1992-01-01

    Confusion over the use of non-video 19 mm data recorders is becoming more pronounced as we enter the world of high performance computing. This paper addresses the following: the differences between ID-1, ID-2, MIL-STD-2179 and DD-2; what the proper machine is for various applications; how the machine can be integrated into an environment; and any misconceptions there might be about 19 mm tape recorders. DD-2 and 19 mm instrumentation recorders have missions for which each is well designed. While the differences may appear subtle, understanding the difference between the two is the key to picking the right recorder for a particular application.

  4. Corneal biomechanical properties changes after coaxial 2.2-mm microincision and standard 3.0-mm phacoemulsification

    PubMed Central

    Zhang, Zhe; Yu, Hua; Dong, Hui; Wang, Li; Jia, Ya-Ding; Zhang, Su-Hua

    2016-01-01

    AIM To compare the changes in corneal biomechanics measured by ocular response analyzer (ORA) after 2.2-mm microincision cataract surgery and 3.0-mm standard coaxial phacoemulsification. METHODS The prospective nonrandomized study comprised eyes with cataract that had 2.2-mm coaxial microincision or 3.0-mm standard incision phacoemulsification. The corneal hysteresis (CH), corneal resistance factor (CRF), corneal-compensated intraocular pressure (IOPcc) and Goldmann-correlated intraocular pressure (IOPg) were measured by ORA preoperatively and at 1d, 1-, 2-, 3- and 4-week postoperatively. Results were analyzed and compared between groups. RESULTS In both groups, CH decreased in the immediate postoperative period (P<0.05), returned to the preoperative level at one week (P=0.249) in the 2.2-mm group, and at two weeks in the 3.0-mm group (P=0.264); there was no significant change in CRF values. In 2.2-mm group, mean IOPcc and IOPg increased at 1d postoperatively (both P<0.05), and returned to preoperative level at one week (P=0.491 and P=0.923, respectively). In 3.0-mm group, mean IOPcc and IOPg increased at 1d and 1wk postoperatively (P=0.005 and P=0.029, respectively), and returned to preoperative level at 2wk (P=0.347 and P=0.887, respectively). CONCLUSION Significant differences between preoperative and postoperative corneal biomechanical values were found for CH, IOPcc and IOPg. But the recovery time courses were different between the two groups. The 2.2-mm coaxial microincision cataract surgery group seemed recovery faster compared to the 3.0-mm standard coaxial phacoemulsification group. PMID:26949640

  5. 35 mm PHOTOGRAPH TAKEN PRIOR TO DEMOLITION OF STRUCTURE. SOUTH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    35 mm PHOTOGRAPH TAKEN PRIOR TO DEMOLITION OF STRUCTURE. SOUTH (SIDE) AND EAST (FRONT) ELEVATIONS OF BUILDING. VIEW TO NORTHWEST - Plattsburgh Air Force Base, Gas Station, New York Road, Plattsburgh, Clinton County, NY

  6. OpenMM: A Hardware Independent Framework for Molecular Simulations

    PubMed Central

    Eastman, Peter; Pande, Vijay S.

    2015-01-01

    The wide diversity of computer architectures today requires a new approach to software development. OpenMM is a framework for molecular mechanics simulations, allowing a single program to run efficiently on a variety of hardware platforms. PMID:26146490

  7. QM/MM investigations of organic chemistry oriented questions.

    PubMed

    Schmidt, Thomas C; Paasche, Alexander; Grebner, Christoph; Ansorg, Kay; Becker, Johannes; Lee, Wook; Engels, Bernd

    2014-01-01

    About 35 years after its first suggestion, QM/MM became the standard theoretical approach to investigate enzymatic structures and processes. The success is due to the ability of QM/MM to provide an accurate atomistic picture of enzymes and related processes. This picture can even be turned into a movie if nuclei-dynamics is taken into account to describe enzymatic processes. In the field of organic chemistry, QM/MM methods are used to a much lesser extent although almost all relevant processes happen in condensed matter or are influenced by complicated interactions between substrate and catalyst. There is less importance for theoretical organic chemistry since the influence of nonpolar solvents is rather weak and the effect of polar solvents can often be accurately described by continuum approaches. Catalytic processes (homogeneous and heterogeneous) can often be reduced to truncated model systems, which are so small that pure quantum-mechanical approaches can be employed. However, since QM/MM becomes more and more efficient due to the success in software and hardware developments, it is more and more used in theoretical organic chemistry to study effects which result from the molecular nature of the environment. It is shown by many examples discussed in this review that the influence can be tremendous, even for nonpolar reactions. The importance of environmental effects in theoretical spectroscopy was already known. Due to its benefits, QM/MM can be expected to experience ongoing growth for the next decade.In the present chapter we give an overview of QM/MM developments and their importance in theoretical organic chemistry, and review applications which give impressions of the possibilities and the importance of the relevant effects. Since there is already a bunch of excellent reviews dealing with QM/MM, we will discuss fundamental ingredients and developments of QM/MM very briefly with a focus on very recent progress. For the applications we follow a similar

  8. Monolithic mm-wave ICs for smart weapons

    NASA Astrophysics Data System (ADS)

    Duffield, T. L.

    1988-04-01

    An approach to developing a low-cost mm-wave transceiver with application to a broad range of smart weapons systems is described. The proposed transceiver technology consists of monolithic mm-wave integrated circuits on GaAs substrates. The relevant transceiver configurations, FET material, and electron beam lithography are discussed. The types of devices to which the approach is applicable are addressed, emphasizing the use of three-terminal devices for all active elements.

  9. The 19 mm date recorders: Similarities and differences

    NASA Technical Reports Server (NTRS)

    Atkinson, Steve

    1991-01-01

    Confusion over the use of non-video 19 mm data recorders is becoming more pronounced in the world of high performance computing. The following issues are addressed: (1) the difference between ID-1, ID-2, MIL-STD-2179, and DD-2; (2) the proper machine for the necessary application; and (3) integrating the machine into an existing environment. Also, an attempt is made to clear up any misconceptions there might be about 19 mm tape recorders.

  10. EGR-1 regulates Ho-1 expression induced by cigarette smoke

    SciTech Connect

    Chen, Huaqun; Wang, Lijuan; Gong, Tao; Yu, Yang; Zhu, Chunhua; Li, Fen; Wang, Li; Li, Chaojun

    2010-05-28

    As an anti-oxidant molecule, heme oxygenase-1 (HO-1) has been implicated in the protection of lung injury by cigarette smoke (CS). The mechanisms regulating its expression have not been defined. In this report, the role of early growth response 1 (EGR-1) in the regulation of Ho-1 expression was investigated. In C57BL/6 mice with CS exposure, HO-1 was greatly increased in bronchial epithelial cells and alveolar inflammatory cells. In primary cultured mouse lung fibroblasts and RAW264.7 cells exposed to cigarette smoke water extract (CSE), an increase in HO-1 protein level was detected. In addition, CSE induced HO-1 expression was decreased in Egr-1 deficient mouse embryo fibroblasts (Egr-1{sup -/-} MEFs). Nuclear localization of EGR-1 was examined in mouse lung fibroblasts after exposure to CSE. Luciferase reporter activity assays showed that the enhancer region of the Ho-1 gene containing a proposed EGR-1 binding site was responsible for the induction of HO-1. A higher increase of alveolar mean linear intercept (Lm) was observed in lung tissues, and a larger increase in the number of total cells and monocytes/macrophages from bronchial alveolar lavage fluid was found in CS-exposed mice by loss of function of EGR-1 treatment. In summary, the present data demonstrate that EGR-1 plays a critical role in HO-1 production induced by CS.

  11. Spectral Line Survey toward the Young Massive Protostar NGC 2264 CMM3 in the 4 mm, 3 mm, and 0.8 mm Bands

    NASA Astrophysics Data System (ADS)

    Watanabe, Yoshimasa; Sakai, Nami; López-Sepulcre, Ana; Furuya, Ryuta; Sakai, Takeshi; Hirota, Tomoya; Liu, Sheng-Yuan; Su, Yu-Nung; Yamamoto, Satoshi

    2015-08-01

    Spectral line survey observations are conducted toward the high-mass protostar candidate NGC 2264 CMM3 in the 4, 3, and 0.8 mm bands with the Nobeyama 45 m telescope and the Atacama Submillimeter Telescope Experiment (ASTE) 10 m telescope. In total, 265 emission lines are detected in the 4 and 3 mm bands, and 74 emission lines in the 0.8 mm band. As a result, 36 molecular species and 30 isotopologues are identified. In addition to the fundamental molecular species, many emission lines of carbon-chain molecules such as HC5N, C4H, CCS, and C3S are detected in the 4 and 3 mm bands. Deuterated molecular species are also detected with relatively strong intensities. On the other hand, emission lines of complex organic molecules such as HCOOCH3 and CH3OCH3 are found to be weak. For the molecules for which multiple transitions are detected, rotation temperatures are derived to be 7-33 K except for CH3OH. Emission lines with high upper-state energies (Eu > 150 K) are detected for CH3OH, indicating the existence of a hot core. In comparison with the chemical composition of the Orion KL, carbon-chain molecules and deuterated molecules are found to be abundant in NGC 2264 CMM3, while sulfur-bearing species and complex organic molecules are deficient. These characteristics indicate the chemical youth of NGC 2264 CMM3 in spite of its location at the center of the cluster forming core, NGC 2264 C.

  12. 2009 Louisiana "HoCP" and "Ho" nursery and infield variety trials

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Three years after selecting in single-stools in the seedling stage, scientists in the breeding program assign “HoCP” or “Ho” numbers to varieties advanced for further testing. These newly assigned varieties are planted in replicated nursery trials at three locations (Ardoyne Farm in Schriever, Iber...

  13. Carbon monoxide stimulates Ca2+ -dependent big-conductance K channels in the cortical collecting duct.

    PubMed

    Wang, Zhijian; Yue, Peng; Lin, Dao-Hong; Wang, Wen-Hui

    2013-03-01

    We used the patch-clamp technique to examine the role of carbon monoxide (CO) in regulating Ca(2+)-activated big-conductance K (BK) channels in the principal cell of the cortical collecting duct (CCD). Application of CORM3 or CORM2, a CO donor, activated BK channels in the CCD, whereas adding inactivated CORM2/3 had no effect. Superfusion of the CCD with CO-bubbled bath solution also activated the BK channels in the cell-attached patches. The effect of CO on BK channels was not dependent on nitric oxide synthase (NOS) because the effect of CORM3 was also observed in the CCD treated with l-NAME, an agent that inhibits the NOS. Adding a membrane-permeable cGMP analog, 8-bromo-cGMP, significantly increased the BK channel in the CCD. However, inhibition of soluble guanylate cyclase failed to abolish the stimulatory effect of CORM3 on BK channels. Moreover, inhibition of cGMP-dependent protein kinase G did not block the stimulatory effect of CORM3 on the BK channels, suggesting that the stimulatory effect of CO on the BK channels was, at least partially, induced by a cGMP-independent mechanism. Western blot demonstrated that heme oxygenase type 1 (HO-1) and HO-2 were expressed in the kidney. Moreover, a high-K (HK) intake increased the expression of HO-1 but not HO-2 in the kidney. A HK intake also increased renal HO activity defined by NADPH-dependent CO generation following addition of heme in the cell lysate from renal cortex and outer medulla. The role of HO in regulating BK channel activity in the CCD was also suggested by experiments in which application of hemin increased the BK channels. The stimulatory effect of hemin on the BK channels was blocked by SnMP, a HO inhibitor. But, adding CORM3 was still able to activate the BK channels in the presence of SnMP. We conclude that CO activates the BK channels, at least partially, through a NO-cGMP-independent pathway and that HO plays a role in mediating the effect of HK intake on the BK channels in the CCD. PMID

  14. Ca2+ current-gated focal and local Ca2+ release in rat atrial myocytes: evidence from rapid 2-D confocal imaging.

    PubMed

    Woo, Sun-Hee; Cleemann, Lars; Morad, Martin

    2002-09-01

    In atrial myocytes immunocytochemistry has shown two groups of ryanodine receptors (RyRs): those at the periphery colocalized with dihydropyridine receptors (DHPRs) and those at the cell interior not associated with DHPRs. The extent to which the two sets of RyRs are controlled by Ca2+ current (I(Ca)) or Ca2+ diffusion remains to be determined. Here, using rapid (240 Hz) two-dimensional confocal Ca2+ imaging in rat atrial myocytes, we examine directly the role of I(Ca) on the two-dimensional patterns of local and focal Ca2+ releases. I(Ca) evoked peripheral Ca2+ release within 1-4 ms, causing a rapid monophasic local rise of Ca2+, which then propagated into the cell interior along sarcomeric lines (approximately 2 microm) with a velocity of approximately 230 microm s(-1), even though we found no evidence for organized t-tubules using di-8-ANEPPS staining. I(Ca)-triggered Ca2+ release in the cell centre, on the other hand, had both a rapid (12 ms) and slower delayed components (12-50 ms). The voltage dependence of peripheral Ca2+ release and the two components of central release was bell shaped, and the magnitude of each release component was linearly related to I(Ca). Premature termination (2-10 ms) of I(Ca) was equally effective in abbreviating both the peripheral and slow central Ca2+ release. High concentration of Ca2+ buffers (2-5 mM EGTA plus 1 mM fluo-3) completely abolished the I(Ca)-gated propagation wave and the slow delayed component of Ca2+ release, but had little or no effect on the rapid component of central release. The efficacy of I(Ca) to trigger Ca2+ release in periphery of the myocyte was approximately 5 times higher than in the centre, consistent with the smaller measured central Ca2+ release. The quantification of central Ca2+ release as a function of peripheral release suggests a cooperative gating mechanism(s) for central release. These findings indicate that both I(Ca) and diffusion of Ca2+ from the peripheral sites contribute to the gating

  15. Measurement of HO2 chemical kinetics with a new detection method

    NASA Technical Reports Server (NTRS)

    Lee, Long C.; Suto, Masako

    1986-01-01

    Reaction rate constants of HO2+O3 were measured at various temperatures using a newly developed HO2 detection method. HO2 was detected by the OH(A-X) emission produced from photodissociative excitation of HO2 at 147 nm. In order to examine the possible interference of other emitting species with the HO2 detection, the photoexcitation processes of all the chemical species existing in the discharge flow tube were also investigated. The results are summarized.

  16. The plasma-membrane Ca2+-ATPase of Leishmania donovani is an extrusion pump for Ca2+.

    PubMed Central

    Mandal, D; Mukherjee, T; Sarkar, S; Majumdar, S; Bhaduri, A

    1997-01-01

    Controlled exposure of Leishmania donovani promastigotes to hypotonic shock results in the formation of deflagellated unsealed ghosts of original polarity that largely retain the pellicular microtubular structure associated with plasma membrane of the parasite. Gentle shearing followed by suspension of the purified membrane in appropriate isotonic buffer containing Mg2+ (4mM) results in the formation of sealed everted vesicles. The presence of Mg2+ (4 mM) appears to be essential for efficient sealing and also to prevent leakiness. ATP-dependent Ca2+ accumulation can be demonstrated in these vesicles Km values for Ca2+ and ATP were 125 nM and 0.8 mM respectively. The accumulated Ca2+ reaches a concentration of 1.1 mM. Ca2+ uptake is completely inhibited by vanadate (40 microM) and several thiol-modifying agents. Using 5,5'-dithiobis-(2-nitrobenzoic acid) as the modifying agent, an excellent correlation between loss of enzyme activity and transport capability and their parallel regeneration in the presence of 2 mM dithiothreitol was demonstrated. Using 2'.7-bis(carboxyethyl)-5(6)-carboxyfluorescein as the fluorescent pH probe, it was observed that Ca2+ entry into the vesicles is accompanied by an outward movement of H+ from the vesicles. Taken together, this paper establishes that the high-affinity transmembrane Ca2+-ATPase [Ghosh, Ray, Sarkar and Bhaduri (1990) J. Biol. Chem. 265, 11345-11351; Majumdar, Mukherjee, Ray and Bhaduri (1992) J. Biol. Chem. 267, 18440-18446] is an extrusion pump for Ca2+ in this human pathogen. PMID:9078270

  17. CMOS mm-wave transceivers for Gbps wireless communication

    NASA Astrophysics Data System (ADS)

    Baoyong, Chi; Zheng, Song; Lixue, Kuang; Haikun, Jia; Xiangyu, Meng; Zhihua, Wang

    2016-07-01

    The challenges in the design of CMOS millimeter-wave (mm-wave) transceiver for Gbps wireless communication are discussed. To support the Gbps data rate, the link bandwidth of the receiver/transmitter must be wide enough, which puts a lot of pressure on the mm-wave front-end as well as on the baseband circuit. This paper discusses the effects of the limited link bandwidth on the transceiver system performance and overviews the bandwidth expansion techniques for mm-wave amplifiers and IF programmable gain amplifier. Furthermore, dual-mode power amplifier (PA) and self-healing technique are introduced to improve the PA's average efficiency and to deal with the process, voltage, and temperature variation issue, respectively. Several fully-integrated CMOS mm-wave transceivers are also presented to give a short overview on the state-of-the-art mm-wave transceivers. Project supported in part by the National Natural Science Foundation of China (No. 61331003).

  18. The brightness temperature of Mercury at mm-wavelengths

    NASA Astrophysics Data System (ADS)

    Greve, A.; Thum, C.; Moreno, R.; Yan, N.

    2009-02-01

    We present observations of Mercury made with the IRAM 30-m telescope at 3, 2 and 1.3 mm wavelength (90, 150 and 230 GHz) during the years 1985-2005; we derive from these data the disk-averaged brightness temperatures. The observations at 3 mm combined with those by Epstein & Andrew allow a separation of the data into 40° wide longitude intervals and by this an investigation of the disk-averaged brightness temperature with Mercury's longitude. From the new mm-wavelength data, and data taken from the literature, we derive the disk-averaged brightness temperature as a function of wavelength. On Mercury's night side a significant decrease in brightness temperature occurs towards shorter wavelengths. We use the three surface models (A,B,C) discussed by Mitchell & de Pater and calculate for the cool and hot surface region the corrresponding diurnal variation of the disk-averaged brightness temperature at 90 GHz. For the same models we calculate the variation of the disk-averaged brightness temperature with wavelength between 1.3 mm and 37 mm, on Mercury's midnight side and noon side. Although the scatter in the observations is large, there seems to be a marginally better agreement with model B and A.

  19. QM/MM calculations with deMon2k.

    PubMed

    Salahub, Dennis R; Noskov, Sergei Yu; Lev, Bogdan; Zhang, Rui; Ngo, Van; Goursot, Annick; Calaminici, Patrizia; Köster, Andreas M; Alvarez-Ibarra, Aurelio; Mejía-Rodríguez, Daniel; Řezáč, Jan; Cailliez, Fabien; de la Lande, Aurélien

    2015-01-01

    The density functional code deMon2k employs a fitted density throughout (Auxiliary Density Functional Theory), which offers a great speed advantage without sacrificing necessary accuracy. Powerful Quantum Mechanical/Molecular Mechanical (QM/MM) approaches are reviewed. Following an overview of the basic features of deMon2k that make it efficient while retaining accuracy, three QM/MM implementations are compared and contrasted. In the first, deMon2k is interfaced with the CHARMM MM code (CHARMM-deMon2k); in the second MM is coded directly within the deMon2k software; and in the third the Chemistry in Ruby (Cuby) wrapper is used to drive the calculations. Cuby is also used in the context of constrained-DFT/MM calculations. Each of these implementations is described briefly; pros and cons are discussed and a few recent applications are described briefly. Applications include solvated ions and biomolecules, polyglutamine peptides important in polyQ neurodegenerative diseases, copper monooxygenases and ultra-rapid electron transfer in cryptochromes. PMID:25786164

  20. The same-source parallel MM{sub 5}.

    SciTech Connect

    Michalakes, J.

    1999-08-23

    The set of architectures available to users of the Penn State/NCAR MM5 has been expanded to included distributed-memory parallel computers, providing cost-effective scalable performance and memory capacity for large problem sizes. The same-source approach uses high-level parallel library and source-translation technology for adapting MM5, simplifying maintenance and allowing new physics modules to be incorporated without modification. The approach facilitates maintenance of the DM-parallel option to MM5 as an option within the official version, rather than as a separate stand-alone version. As a result, the DM-parallel option to MM5 (now at Version 3.1) has been a part of six subsequent model releases since MM5 Version 2.8 in March 1998. The same-source approach is applicable to other, similarly constructed codes when there is a need or desire to develop the code for distributed memory parallel machines without impacting the pre-existing source code. The approach is also compatible with pre-existing loop-level multithreading directives so that the code will run in distributed-memory/shared-memory mode on SMP clusters.

  1. Clopidogrel Protects Endothelium by Hindering TNFα-Induced VCAM-1 Expression through CaMKKβ/AMPK/Nrf2 Pathway

    PubMed Central

    Yang, Huabing; Zhao, Pengjun; Tian, Shiliu

    2016-01-01

    Clopidogrel (INN), an oral antiplatelet drug, has been revealed to have a number of biological properties, for instance, anti-inflammation and antioxidation. Oxidative stress plays an imperative role in inflammation, diabetes mellitus, atherosclerosis, and cancer. In the present study, human aortic endothelial cells (HAECs) were employed to explore the anti-inflammatory activity of INN. INN reduced TNFα-induced reactive oxygen species (ROS) generation and time-dependently prompted the expression and activity of heme oxygenase 1 (HO-1). Cellular glutathione (GSH) levels were augmented by INN. shHO-1 blocked the INN suppression of TNFα-induced HL-60 cell adhesion. The CaMKKβ/AMPK pathway and Nrf2 transcriptional factor were implicated in the induction of HO-1 by INN. Additionally, TNFα dramatically augmented VCAM-1 expression at protein and mRNA levels. INN treatment strikingly repressed TNFα-induced expression of VCAM-1 and HL-60 cell adhesion. Compound C, an AMPK inhibitor, and shNrf2 abolished TNFα-induced expression of VCAM-1 and HL-60 cell adhesion. Our data suggest that INN diminishes TNFα-stimulated VCAM-1 expression at least in part via HO-1 induction, which is CaMKKβ/AMPK pathway-dependent. PMID:26824050

  2. IRRS, UV-Vis-NIR absorption and photoluminescence upconversion in Ho 3+-doped oxyfluorophosphate glasses

    NASA Astrophysics Data System (ADS)

    Karmakar, Basudeb

    2005-09-01

    Infrared reflection spectroscopic (IRRS), ultraviolet-visible-near infrared (UV-Vis-NIR) absorption and photoluminescence upconversion properties with special emphasis on the spectrochemistry of the oxyfluorophosphate (oxide incorporated fluorophosphates) glasses of the Ba(PO 3) 2-AlF 3-CaF 2-SrF 2-MgF 2-Ho 2O 3 system have been studied with different concentrations (0.1, 0.3 and 1.0 mol%) of Ho 2O 3. IRRS spectral band position and intensity of Ho 3+ ion doped oxyfluorophosphate glasses have been discussed in terms of reduced mass and force constant. UV-Vis-NIR absorption band position has been justified with quantitative calculation of nephelauxetic parameter and covalent bonding characteristics of the host. NIR to visible upconversion has been investigated by exciting at 892 nm at room temperature. Three upconverted bands originated from the 5F 3→ 5I 8, ( 5S 2, 5F 4)→ 5I 8 and 5F 5→ 5I 8 transitions have found to be centered at 491 nm (blue, medium), 543 nm (green, very strong) and 658 nm (red, weak), respectively. These bands have been justified from the evaluation of the absorption, normal (down conversion) fluorescence and excitation spectra. The upconversion processes have been explained by the excited state absorption (ESA), energy transfer (ET) and cross relaxation (CR) mechanisms involving population of the metastable (storage) energy levels by multiphonon deexcitation effect. It is evident from the IRRS study that the upconversion phenomena are expedited by the low multiphonon relaxation rate in oxyfluorophosphate glasses owing to their high intense low phonon energy (˜600 cm -1) which is very close to that of fluoride glasses (500-600 cm -1).

  3. Heterogeneous Uptake of HO2 Radicals onto Atmospheric Aerosols

    NASA Astrophysics Data System (ADS)

    George, I. J.; Matthews, P. S.; Brooks, B.; Goddard, A.; Whalley, L. K.; Baeza-Romero, M. T.; Heard, D. E.

    2011-12-01

    The hydroxyl (OH) and hydroperoxyl (HO2) radicals, together known as HOx, play a vital role in atmospheric chemistry by controlling the oxidative capacity of the troposphere. The atmospheric lifetime and concentrations of many trace reactive species, such as volatile organic compounds (VOCs), are determined by HOx radical levels. Therefore, the ability to accurately predict atmospheric HOx concentrations from a detailed knowledge of their sources and sinks is a very useful diagnostic tool to assess our current understanding of atmospheric chemistry. Several recent field studies have observed significantly lower concentrations of HO2 radicals than predicted using box models, where HO2 loss onto aerosols was suggested as a possible missing sink [1, 2]. However, the mechanism on HO2 uptake onto aerosols and its impact on ambient HOx levels are currently not well understood. To improve our understanding of this process, we have conducted laboratory experiments to measure HO2 uptake coefficients onto submicron aerosol particles. The FAGE (Fluorescence Assay by Gas Expansion) technique, a highly sensitive laser induced fluorescence based detection method, was used to monitor HO2 uptake kinetics onto aerosol particles in an aerosol flow tube. The application of the FAGE technique allowed for kinetic experiments to be performed under low HO2 concentrations, i.e. [HO2] < 109 molecules cm-3. HO2 radicals were produced by the photolysis of water vapour in the presence of O2 and aerosol particles were produced either by atomizing dilute salt solutions or by homogeneous nucleation. HO2 uptake coefficients (γ) have been measured for single-component solid and aqueous inorganic salt and organic aerosol particles with a wide range of hygroscopicities. HO2 uptake coefficients on solid particles were below the detection limit (γ < 0.001), whereas on aqueous aerosols uptake coefficients were somewhat larger (γ = 0.001 - 0.008). HO2 uptake coefficients were highest on aerosols

  4. Cytosolic and mitochondrial [Ca2+] in whole hearts using indo-1 acetoxymethyl ester: effects of high extracellular Ca2+.

    PubMed Central

    Schreur, J H; Figueredo, V M; Miyamae, M; Shames, D M; Baker, A J; Camacho, S A

    1996-01-01

    Assessment of free cytosolic [Ca2+] ([Ca2+]c) using the acetoxymethyl ester (AM) form of indo-1 may be compromised by loading of indo-1 into noncytosolic compartments, primarily mitochondria. To determine the fraction of noncytosolic fluorescence in whole hearts loaded with indo-1 AM, Mn2+ was used to quench cytosolic fluorescence. Residual (i.e., noncytosolic) fluorescence was subtracted from the total fluorescence before calculating [Ca2+]c. Noncytosolic fluorescence was used to estimate mitochondrial [Ca2+]. In hearts paced at 5 Hz (N = 17), noncytosolic fluorescence was 0.61 +/- 0.06 and 0.56 +/- 0.07 of total fluorescence at lambda 385 and lambda 456, respectively. After taking into account noncytosolic fluorescence, systolic and diastolic [Ca2+]c was 673 +/- 72 and 132 +/- 9 nM, respectively, noncytosolic [Ca2+] was 183 +/- 36 nM and increased to 272 +/- 12 when extracellular Ca2+ was increased from 2 to 6 mM. This increase in noncytosolic [Ca2+] was inhibited by ruthenium red, a blocker of Ca2+ uptake by mitochondria. We conclude that cytosolic and mitochondrial [Ca2+] can be determined in whole hearts loaded with indo-1 AM by using Mn2+ to quench cytosolic fluorescence. PMID:8744296

  5. QM/MM X-ray Refinement of Zinc Metalloenzymes

    PubMed Central

    Li, Xue; Hayik, Seth A.; Merz, Kenneth M.

    2010-01-01

    Zinc metalloenzymes play an important role in biology. However, due to the limitation of molecular force field energy restraints used in X-ray refinement at medium or low resolutions, the precise geometry of the zinc coordination environment can be difficult to distinguish from ambiguous electron density maps. Due to the difficulties involved in defining accurate force fields for metal ions, the QM/MM (Quantum-Mechanical /Molecular-Mechanical) method provides an attractive and more general alternative for the study and refinement of metalloprotein active sites. Herein we present three examples that indicate that QM/MM based refinement yields a superior description of the crystal structure based on R and Rfree values and on the inspection of the zinc coordination environment. It is concluded that QM/MM refinement is a useful general tool for the improvement of the metal coordination sphere in metalloenzyme active sites. PMID:20116858

  6. Engineering Strong Interactions Between mm-wave and Optical Photons

    NASA Astrophysics Data System (ADS)

    Stone, Mark; Suleymanzade, Aziza; Estes, Jeremy; Eustice, Scott; Schuster, David; Simon, Jonathan

    2016-05-01

    We propose an atomic interface of Rydberg atoms as a means of engineering effective strong interactions between single mm-wave and optical photons. The atomic sample resides at the intersection of a high-finesse optical cavity and a superconducting mm-wave cavity, where it can coherently interact with photons of both regimes. The use of mm-wave (100 GHz) frequencies allows strong coupling at higher temperatures and with less sensitivity to stray electric fields. A hybrid cryogenic vacuum chamber at 4 Kelvin enables access to superconductivity as well as a UHV environment with optical access necessary for cold atom experiments. Strong interactions between these separate quantum degrees of freedom has important applications in quantum computing as well as simulation of many-body interacting systems.

  7. Studies of Ca{sup 2+} binding in spinach photosytem II using {sup 45}Ca{sup 2+}

    SciTech Connect

    Aedelroth, P.; Lindberg, K.; Andreasson, L.E.

    1995-07-18

    The Ca{sup 2+}-binding properties of photosystem II were investigated with radioactive {sup 45}Ca{sup 2+}. PS II membranes, isolated from spinach grown on a medium containing {sup 45}Ca{sup 2+}, contained 1.5 Ca{sup 2+} per PS II unit. Approximately half of the incorporated radioactivity was lost after incubation for 30 h in nonradioactive buffer. About 1 Ca{sup 2+}/PS II bound slowly to Ca{sup 2+}-depleted membranes in the presence of the extrinsic 16- and 23-kDa polypeptides in parallel with restoration of oxygen-evolving activity. The binding was heterogeneous with dissociation constants of 60 {mu}M (0.7 Ca{sup 2+}/PS II) and 1.7 mM (0.3 Ca{sup 2+}/ PS II), respectively, which could reflect different affinities of the dark-stable S-states for Ca{sup 2+}. The reactivation of oxygen-evolving activity closely followed the binding of Ca{sup 2+}, showing that a single exchangeable Ca{sup 2+} per PS II is sufficient for the water-splitting reaction to function. In PS II, depleted of the 16- and 23-kDa polypeptides, about 0.7 exchangeable Ca{sup 2+}/PS II binds with a dissociation constant of 26 {mu}M, while 0.3 Ca{sup 2+} binds with a much weaker affinity (K{sub d} > 0.5 mM). The rate of binding of Ca{sup 2+} in the absence of the two extrinsic polypeptides was significantly higher than with the polypeptides bound. The rate of dissociation of bound Ca{sup 2+} in the dark, which had a half-time of about 80 h in intact PS H, increased in the absence of the 16-and 23-kDa polypeptides and showed a further increase after the additional removal of the 33-kDa protein and manganese. The rate of dissociation was also significantly faster in weak light than in the dark. Removal of the 33-kDa donor-side polypeptide together with the two lighter ones led to a reduction in the amount of bound Ca{sup 2+}, while practically no Ca{sup 2+} bound after treatments to dissociate also the manganese of the water-oxidizing site. 34 refs., 9 figs., 2 tabs.

  8. 450mm wafer patterning with jet and flash imprint lithography

    NASA Astrophysics Data System (ADS)

    Thompson, Ecron; Hellebrekers, Paul; Hofemann, Paul; LaBrake, Dwayne L.; Resnick, Douglas J.; Sreenivasan, S. V.

    2013-09-01

    The next step in the evolution of wafer size is 450mm. Any transition in sizing is an enormous task that must account for fabrication space, environmental health and safety concerns, wafer standards, metrology capability, individual process module development and device integration. For 450mm, an aggressive goal of 2018 has been set, with pilot line operation as early as 2016. To address these goals, consortiums have been formed to establish the infrastructure necessary to the transition, with a focus on the development of both process and metrology tools. Central to any process module development, which includes deposition, etch and chemical mechanical polishing is the lithography tool. In order to address the need for early learning and advance process module development, Molecular Imprints Inc. has provided the industry with the first advanced lithography platform, the Imprio® 450, capable of patterning a full 450mm wafer. The Imprio 450 was accepted by Intel at the end of 2012 and is now being used to support the 450mm wafer process development demands as part of a multi-year wafer services contract to facilitate the semiconductor industry's transition to lower cost 450mm wafer production. The Imprio 450 uses a Jet and Flash Imprint Lithography (J-FILTM) process that employs drop dispensing of UV curable resists to assist high resolution patterning for subsequent dry etch pattern transfer. The technology is actively being used to develop solutions for markets including NAND Flash memory, patterned media for hard disk drives and displays. This paper reviews the recent performance of the J-FIL technology (including overlay, throughput and defectivity), mask development improvements provided by Dai Nippon Printing, and the application of the technology to a 450mm lithography platform.

  9. Laparoscopic 5-mm Trocar Site Herniation and Literature Review

    PubMed Central

    Minikel, Laura; Zaritsky, Eve

    2011-01-01

    Objective: To evaluate the evidence for fascial closure of 5-mm laparoscopic trocar sites. Methods: We conducted electronic database searches of PubMed and the Cochrane Library for articles published between November 2008 and December 2010. We used the keywords trocar hernia, trocar-site hernia, laparoscopic hernia, trocar port-site hernia, laparoscopic port-site hernia. Prospective and retrospective case series, randomized trials, literature reviews, and randomized animal studies of trocar hernias on abdominal wall defects from gynecologic, urologic, and general surgery literature were reviewed. The Cochrane Database was reviewed for pertinent studies. Metaanalysis was not possible due to the significant heterogeneity between studies and lack of randomized trials large enough to assess the incidence of this rare complication. Results: Trocar-site hernias are a rare but known complication of laparoscopic surgery. Trocar size ≥10mm is associated with an increased rate of hernia development. Currently, the accepted gynecologic surgical practice is closure of fascial incisions ≥10mm, while incisions <10mm do not require closure. However, large prospective and retrospective case series reports from general surgery and urology literature support nonclosure of blunt or radially dilating trocars in paramedian sites. Expert opinion and small case reports suggest that in cases of prolonged manipulation of 5-mm trocar sites the surgeon should consider fascial closure, because extension of the initial incision may have occurred. Conclusion: There is no evidence to recommend routine closure of 5-mm trocar incisions; the choice should continue to be left to the discretion of the individual surgeon. PMID:21902958

  10. Magnetic remanence in Yb14-xRExMnSb11 (RE=Tb, Dy, Ho) single crystals

    NASA Astrophysics Data System (ADS)

    Grebenkemper, Jason H.; Hu, Yufei; Abdusalyamova, M. N.; Makhmudov, F. A.; Kauzlarich, Susan M.

    2016-06-01

    Single crystals of Yb14-xRExMnSb11 (x~0.1, 0.4; RE = Tb, Dy, Ho) have been prepared as a solid solution by Sn flux reactions of the elements. They crystallize in the Ca14AlSb11 structure type in the I41/acd space group. The RE3+preferentially substitutes on the Yb(1) site which is the smallest volume Yb containing polyhedron. In the case of Ho3+, a small amount of Ho3+ also substitutes on the Yb(4) site. The ferromagnetic ordering temperature of Yb14MnSb11 is reduced from 53 K to 41 K as x increases and dependent on the identity of the RE. This is attributed to the reduction in carriers and reduced screening of the Mn2+ local moment. The effective moments, μeff, agree well with the calculated moments assuming the RE substitutes as a trivalent cation. The largest coercive field is observed for RE = Dy (1000 Oe). For the maximum x of Yb14-xRExMnSb11 there are enough carriers for the Ruderman-Kittel-Kasuya-Yosida (RKKY) mechanism of magnetic coupling via conduction electrons to still be valid in describing the ferromagnetic ordering.