Cu4Pr6(MoO4)11-Pr2(MoO4)3 system

International Nuclear Information System (INIS)

Arzumanyan, G.A.

1982-01-01

Existence boundaries and Dalton compositions (CuPr(MoO 4 ) 2 , CuPr 3 (MoO 4 ) 5 ) of solid solutions that in the mojority are of shcheelite dsitored structure have been determined in the Cu 4 Pr 6 (MoO 4 ) 11 -Pr 2 (MoO 4 ) 3 system. It has been revealed that regions of homogeneity near the CuPr(MoO 4 ) 2 composition have a horseshoeshaped profile

77 FR 37445 - Notice of Permit Modification Received Under the Antarctic Conservation Act of 1978 (Pub. L. 95-541)

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2012-06-21

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2010-11-05

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Electronic structures of PrBa2Cu3O7, Pr2Ba4Cu7O15-y(y=0,1), and PrBa2Cu4O8 based on LSDA+U method

International Nuclear Information System (INIS)

Tavana, A.; Shirazi, M.; Akhavan, M.

2009-01-01

The electronic structures of PrBa 2 Cu 3 O 7 (Pr123), Pr 2 Ba 4 Cu 7 O 15-y (Pr247), and PrBa 2 Cu 4 O 8 (Pr124) cuprates have been obtained using density-functional theory in the local spin density approximation plus onsite Coulomb interaction (LSDA+U). Onsite Hubbard correlation, U, has been considered for Pr-f and Cu-d orbitals and the effects of considering these correlation corrections on the Pr-O hybridizations have been inspected. Results imply that the Pr ionization state in Pr123 system is constituted from two different configurations, and the energy of the f states in these two configurations has an important role in superconductivity properties of the system. Our calculations also show that in both Pr124 and Pr247 systems, suppression of superconductivity is weaker than that in the Pr123 system. This occurs due to the weaker Pr-O bond in both Pr124 and Pr247 systems. The role of the double chain and single chain on the conduction properties of these compounds has been investigated. We have also studied the effect of oxygen deficiency in Pr247 system, which seems to revive superconductivity in this system. Investigating the hole carriers in the CuO 2 plane shows a correlation between superconductivity suppression and hole decrement in the planes. (Abstract Copyright [2009], Wiley Periodicals, Inc.)

75 FR 42436 - Houston Pipe Line Company LP-Bammel Storage, Docket No. PR10-51-000, et. al.; Notice of Baseline...

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2010-07-21

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Houston Pipe Line Company LP--Bammel Storage, Docket No. PR10-51- 000, et. al.; Notice of Baseline Filings July 14, 2010. Houston Pipe Line..., 2010, respectively the applicants listed above submitted their baseline filing of its Statement of...

Phase relations in the SiC-Al2O3-Pr2O3 system

International Nuclear Information System (INIS)

Pan, W.; Wu, L.; Jiang, Y.; Huang, Z.

2016-01-01

Phase relations in the Si-Al-Pr-O-C system, including the SiC-Al 2 O 3 -Pr 2 O 3 , the Al 2 O 3 -Pr 2 O 3 -SiO 2 and the SiC-Al 2 O 3 -Pr 2 O 3 -SiO 2 subsystems, were determined by means of XRD phase analysis of solid-state-reacted samples fabricated by using SiC, Al 2 O 3 , Pr 2 O 3 and SiO 2 powders as the starting materials. Subsolidus phase diagrams of the systems were presented. Two Pr-aluminates, namely PrAlO 3 (PrAP) and PrAl 11 O 18 (β(Pr) β-Al 2 O 3 type) were formed in the SiC-Al 2 O 3 -Pr 2 O 3 system. SiC was compatible with both of them. Pr-silicates of Pr 2 SiO 5 , Pr 2 Si 2 O 7 and Pr 9.33 Si 6 O 26 (H(Pr) apatite type) were formed owing to presence of SiO 2 impurity in the SiC powder. The presence of the SiO 2 extended the ternary system of SiC-Al 2 O 3 -Pr 2 O 3 into a quaternary system of SiC-Al 2 O 3 -SiO 2 -Pr 2 O 3 (Si-Al-Pr-O-C). SiC was compatible with Al 2 O 3 , Pr 2 O 3 and the Pr-silicates. The effect of SiO 2 on the phase relations and liquid phase sintering of SiC ceramics was discussed.

Electronic structures of PrBa2Cu3O7 and PrBa2Cu4O8 systems based on LSDA+U approach

International Nuclear Information System (INIS)

Shirazi, M.; Tavana, A.; Akhavan, M.

2007-01-01

Full text: The electronic structures of PrBa 2 Cu 3 O 7 (Pr123) and PrBa 2 Cu 4 O 8 (Pr124) have been obtained by means of the density functional theory in the local spin density approximation plus on-site Coulomb interaction. The correlation correction has been applied to the Cu 3d and Pr 4f states. Calculations show that the localized Pr-O bands form near the Fermi surface and do not cross the Fermi level. Comparison of the hole absorbing ability of pfy and the pdy states shows that pfy state has dominant role in grabbing holes from the system and causes Pr124 to be non-superconducting like Pr123. We suggest that hybridization of Pr and O atoms in Pr124 system is weaker than Pr123 compound and this may be the reason for the higher critical doping of Pr by which the superconductivity is completely suppressed. Displacement of the conduction bands at the Fermi level is the criterion of Cu (3dx2-y2) character, and when Cu (3dx2-y2) character is stronger in a band, the band displaces more intensively under applying the correction Ucu. We estimate the hole-concentration from this displacement, and good agreement with experiment is seen. The displacement of the CuO 2 plane bands in the minority and majority spin channels in Pr124 is less than that in Pr123. Displacement of the double chain bands in Pr124 is higher than the single chain bands in Pr123. This feature is related to a stronger Cu (3dx2-y2) character in the double chain. So, the spin and conduction features of the Pr124 double chains are stronger than Pr123 single chain, which is the origin of metallic behavior of Pr124 at low temperatures.(authors)

Electronic structures of PrBa2Cu3O7 and PrBa2Cu4O8 systems based on LSDA+U approach

International Nuclear Information System (INIS)

Shirazi, M.; Tavana, A.; Akhavan, M.

2007-01-01

Full text: The electronic structures of PrBa 2 Cu 3 O 7 (Pr123) and PrBa 2 Cu 4 O 8 (Pr124) have been obtained by means of the density functional theory in the local spin density approximation plus on-site Coulomb interaction. The correlation correction has been applied to the Cu 3d and Pr 4f states. Calculations show that the localized Pr-O bands form near the Fermi surface and do not cross the Fermi level. Comparison of the hole absorbing ability of pfy and the pdy states shows that pfy state has dominant role in grabbing holes from the system and causes Pr124 to be non-superconducting like Pr123. We suggest that hybridization of Pr and O atoms in Pr124 system is weaker than Pr123 compound and this may be the reason for the higher critical doping of Pr by which the superconductivity is completely suppressed. Displacement of the conduction bands at the Fermi level is the criterion of Cu (3dx2-y2) character, and when Cu (3dx2-y2) character is stronger in a band, the band displaces more intensively under applying the correction Ucu. We estimate the hole-concentration from this displacement, and good agreement with experiment is seen. The displacement of the CuO 2 plane bands in the minority and majority spin channels in Pr124 is less than that in Pr123. Displacement of the double chain bands in Pr124 is higher than the single chain bands in Pr123. This feature is related to a stronger Cu (3dx2-y2) character in the double chain. So, the spin and conduction features of the Pr124 double chains are stronger than Pr123 single chain, which is the origin of metallic behavior of Pr124 at low temperatures. (authors)

Impact of chemotherapy relative dose intensity on cause-specific and overall survival for stage I-III breast cancer: ER+/PR+, HER2- vs. triple-negative.

Science.gov (United States)

Zhang, Lu; Yu, Qingzhao; Wu, Xiao-Cheng; Hsieh, Mei-Chin; Loch, Michelle; Chen, Vivien W; Fontham, Elizabeth; Ferguson, Tekeda

2018-05-01

To investigate the impact of chemotherapy relative dose intensity (RDI) on cause-specific and overall survival for stage I-III breast cancer: estrogen receptor or progesterone receptor positive, human epidermal-growth factor receptor negative (ER+/PR+ and HER2-) vs. triple-negative (TNBC) and to identify the optimal RDI cut-off points in these two patient populations. Data were collected by the Louisiana Tumor Registry for two CDC-funded projects. Women diagnosed with stage I-III ER+/PR+, HER2- breast cancer, or TNBC in 2011 with complete information on RDI were included. Five RDI cut-off points (95, 90, 85, 80, and 75%) were evaluated on cause-specific and overall survival, adjusting for multiple demographic variables, tumor characteristics, comorbidity, use of granulocyte-growth factor/cytokines, chemotherapy delay, chemotherapy regimens, and use of hormone therapy. Cox proportional hazards models and Kaplan-Meier survival curves were estimated and adjusted by stabilized inverse probability treatment weighting (IPTW) of propensity score. Of 494 ER+/PR+, HER2- patients and 180 TNBC patients, RDI PR+, HER2- patients, 85% was the only cut-off point at which the low RDI was significantly associated with worse overall survival (HR = 1.93; 95% CI 1.09-3.40). Among TNBC patients, 75% was the cut-off point at which the high RDI was associated with better cause-specific (HR = 2.64; 95% CI 1.09, 6.38) and overall survival (HR = 2.39; 95% CI 1.04-5.51). Higher RDI of chemotherapy is associated with better survival for ER+/PR+, HER2- patients and TNBC patients. To optimize survival benefits, RDI should be maintained ≥ 85% in ER+/PR+, HER2- patients, and ≥ 75% in TNBC patients.

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Cathodoluminescence properties of SiO2:Pr3+and ZnO.SiO2:Pr3+ phosphor nanopowders

CSIR Research Space (South Africa)

Mhlongo, GH

2010-10-01

Full Text Available regardless of the incorporation of Pr3+ and nanocrystalline ZnO or annealing at 600 °C. The particles were mostly spherical and agglomerated as confirmed by Field Emission Scanning Electron Microscopy. Thermogravimetric analysis of dried gels performed... Science, vol. 45(19): 5228-5236 Cathodoluminescence properties of SiO2:Pr 3+and ZnO·SiO2:Pr 3+ phosphor nanopowders G. H. Mhlongo, O. M. Ntwaeaborwa, M. S. Dhlamini, H. C. Swart, K. T. Hillie ABSTRACT: The successful incorporation of Zn...

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Energy transfer of the quantum-cutter couple Pr{sup 3+}–Mn{sup 2+} in CaF{sub 2}:Pr{sup 3+}, Mn{sup 2+} nanoparticles

Energy Technology Data Exchange (ETDEWEB)

Kuzmanoski, Ana [Karlsruhe Institute of Technology (KIT), Institute of Inorganic Chemistry, Engesserstraße 15, D-76131 Karlsruhe (Germany); Pankratov, Vladimir, E-mail: vpank@latnet.lv [Research Center of Molecular Materials, University of Oulu, PO Box 3000, 90014 Oulu (Finland); Feldmann, Claus, E-mail: claus.feldmann@kit.edu [Karlsruhe Institute of Technology (KIT), Institute of Inorganic Chemistry, Engesserstraße 15, D-76131 Karlsruhe (Germany)

2016-11-15

CaF{sub 2}:Pr (1 mol%), CaF{sub 2}:Mn (5 mol%) and CaF{sub 2}:Pr,Mn (1 mol%, 5 mol%) nanoparticles are prepared via a microwave-mediated synthesis in ionic liquids. The nanoparticles are highly crystalline and exhibit particle diameters <50 nm.In contrast to bulk-CaF{sub 2}:Pr,Mn,energy transfer between Pr{sup 3+}and Mn{sup 2+}under {sup 1}S{sub 0}→{sup 1}I{sub 6} relaxation on Pr{sup 3+} and {sup 4}G({sup 4}T{sub 1g})→{sup 6}S(A{sub 1g}) emission of Mn{sup 2+} is observed for the first time. Such energy transfer represents the essential first step of the quantum-cutting cascade via the Pr{sup 3+}–Mn{sup 2+} couple, which is most interesting as both expected photons – {sup 3}P{sub 0}→{sup 3}H{sub 4} emission of Pr{sup 3+}and {sup 4}G({sup 4}T{sub 1g})→{sup 6}S(A{sub 1g}) emission of Mn{sup 2+} – are emitted in the green spectral range. While bulk crystals were said not to show energy transfer due to prohibiting selection rules, vacuum ultraviolet (VUV) spectroscopy of CaF{sub 2}:Pr, Mn nanoparticles firstly proves efficient Pr{sup 3+}→Mn{sup 2+} energy transfer, which can be ascribed to the reduced site symmetry and considerable spin–orbit interaction in the nanocrystals.

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Magnetic and thermodynamic properties of the Pr-based ferromagnet PrGe2-δ

Science.gov (United States)

Matsumoto, Keisuke T.; Morioka, Naoya; Hiraoka, Koichi

2018-03-01

We investigated the magnetization, M, and specific heat, C, of ThSi2-type PrGe2-δ. A polycrystalline sample of PrGe2-δ was prepared by arc-melting. Magnetization divided by magnetic field, M / B, increased sharply and C showed a clear jump at the Curie temperature, TC, of 14.6 K; these results indicate that PrGe2-δ ordered ferromagnetically. The magnetic entropy at TC reached R ln 3, indicating a quasi-triplet crystalline electric field (CEF) ground state. The maximum value of magnetic entropy change was 11.5 J/K kg with a field change of 7 T, which is comparable to those of other right rare-earth based magnetocaloric materials. This large magnetic entropy change was attributed to the quasi-triplet ground state of the CEF.

Electronic conductivity of Ce(0.9)Gd(0.1)O(1.95-δ) and Ce(0.8)Pr(0.2)O(2-δ): Hebb-Wagner polarisation in the case of redox active dopants and interference

DEFF Research Database (Denmark)

Chatzichristodoulou, Christodoulos; Hendriksen, Peter Vang

2011-01-01

of the steady state I-V curve from the standard Hebb-Wagner equation was observed for the case of Ce(0.8)Pr(0.2)O(2-δ). It is shown that the I-V curve can be successfully reproduced when the presence of the redox active dopant, Pr(3+)/Pr(4+), is taken into account, whereas even better agreement can be reached...

Magnetic properties of PrMn2-xFexGe2-57Fe Moessbauer spectroscopy

International Nuclear Information System (INIS)

Wang, J L; Campbell, S J; Cadogan, J M; Tegus, O; Studer, A J; Hofmann, M

2006-01-01

We have investigated the magnetic behaviour of PrMn 2-x Fe x Ge 2 compounds with x = 0.4, 0.6 and 0.8 over the temperature range 4.2-350 K using ac magnetic susceptibility, dc magnetization and 57 Fe Moessbauer effect spectroscopy, as well as neutron diffraction for the PrMn 1.2 Fe 0.8 Ge 2 compound. Replacement of Mn with Fe leads to contraction of the unit cell and a shortening of the Mn-Mn spacing, resulting in modification of the magnetic structure. PrMn 1.6 Fe 0.4 Ge 2 is an intralayer antiferromagnet at room temperature and ferromagnetic below T C inter ∼230 K with additional ferromagnetic ordering of the Pr sublattice detected below T C Pr ∼30 K. Re-entrant ferromagnetism has been observed in PrMn 1.4 Fe 0.6 Ge 2 with four magnetic transitions (T N intra ∼333 K, T C inter ∼168 K, T N inter ∼152 K and T C Pr ∼40 K). Moreover, it was found that T C inter and T C Pr increase with applied field while T N inter decreases. PrMn 1.2 Fe 0.8 Ge 2 is antiferromagnetic with T N intra ∼242 K and T N inter ∼154 K. The magnetic transition temperatures for all compounds are also marked by changes in the 57 Fe magnetic hyperfine field and the electric quadrupole interaction parameters. The 57 Fe transferred hyperfine field at 4.5 K in PrMn 1.6 Fe 0.4 Ge 2 and PrMn 1.4 Fe 0.6 Ge 2 is reduced (below the ordering temperature of the Pr sublattice) compared with that at 80 K (above T C Pr ), indicating that the transferred hyperfine field from Pr acts in the opposite direction to that from the Mn atoms. The neutron data for PrMn 1.2 Fe 0.8 Ge 2 demonstrate that an anisotropic thermal expansion occurs within the interplanar antiferromagnetic range

Studies in the Crystalline Electric Field in Pr2 Al and Pr Al by the Inelastic Neutron Scattering Method

International Nuclear Information System (INIS)

Slisenko, V.I.; Ivanitskij, P.G.; Vasil'kevich, A.A.; Krotenko, V.T.; Majstrenko, A.N.

1993-01-01

Results of inelastic neutron scattering in polycrystalline Pr 2 Al and Pr Al are reported. The parameters of the crystal field Hamiltonian for the orthorhombic point symmetry of the Pr 3+ ions in Pr 2 Al and Pr Al are derived from neutron spectra. Using These parameters the magnetic contribution to the specific heat is calculated

Glycan-deficient PrP stimulates VEGFR2 signaling via glycosaminoglycan.

Science.gov (United States)

Gao, Zhenxing; Zhang, Huixia; Hu, Fei; Yang, Liheng; Yang, Xiaowen; Zhu, Ying; Sy, Man-Sun; Li, Chaoyang

2016-06-01

Whether the two N-linked glycans are important in prion, PrP, biology is unresolved. In Chinese hamster ovary (CHO) cells, the two glycans are clearly not important in the cell surface expression of transfected human PrP. Compared to fully-glycosylated PrP, glycan-deficient PrP preferentially partitions to lipid raft. In CHO cells glycan-deficient PrP also interacts with glycosaminoglycan (GAG) and vascular endothelial growth factor receptor 2 (VEGFR2), resulting in VEGFR2 activation and enhanced Akt phosphorylation. Accordingly, CHO cells expressing glycan-deficient PrP lacking the GAG binding motif or cells treated with heparinase to remove GAG show diminished Akt signaling. Being in lipid raft is critical, chimeric glycan-deficient PrP with CD4 transmembrane and cytoplasmic domains is absent in lipid raft and does not activate Akt signaling. CHO cells bearing glycan-deficient PrP also exhibit enhanced cellular adhesion and migration. Based on these findings, we propose a model in which glycan-deficient PrP, GAG, and VEGFR2 interact, activating VEGFR2 and resulting in changes in cellular behavior. Copyright © 2016 Elsevier Inc. All rights reserved.

Cs2SO4-Pr2(SO4)3-H2O and NiSO4-Pr2(SO4)3-H2O systems at 75 deg C

International Nuclear Information System (INIS)

Onishchenko, M.K.; Skorikov, V.M.; Shevchuk, V.G.; AN SSSR, Moscow. Inst. Obshchej i Neorganicheskoj Khimii)

1979-01-01

To investigate physico-chemical properties of equilibrium saturated solutions and to elucidate the chemical changes under way, the aqueous systems of cesium, nickel and praseodymium (3) sulfates are studied. The method of isothermal saturation of salts at 75 deg C is used. It has been found that in the system Cs 2 SO 4 -Pr 2 (SO 4 ) 3 -H 2 O in a wide concentration range the soluble binary salt Cs 2 SO 4 xPr 2 (SO 4 ) 3 csytallizes in a congruent way. For the system NiSO 4 -Pr 2 (SO 4 ) 3 -H 2 O a solubility curve of the eutonic type is obtained, there being no chemical interaction between the components. The solubility isotherms for the system are given

Luminescence of the SrCl2:Pr crystals under high-energy excitation

International Nuclear Information System (INIS)

Antonyak, O.T.; Voloshinovskii, A.S.; Vistovskyy, V.V.; Stryganyuk, G.B.; Kregel, O.P.

2014-01-01

The present research was carried out in order to elucidate the mechanisms of energy transfer from the crystal lattice to Pr 3+ ions in SrCl 2 . The luminescence excitation and emission spectra as well as luminescence kinetics of the SrCl 2 :Pr single crystals containing 0.2 mol% Pr were investigated at 300 and 10 K using the vacuum ultraviolet (VUV) synchrotron radiation. The X-ray excited luminescence spectra of the SrCl 2 :Pr (C Pr =0.2 and 0.5 mol%) and SrCl 2 :Pr, K (C Pr =1.5 mol%; C K =1.5 mol%) crystals were studied at 294 and 80 K. Under optical excitation of the samples in the Pr 3+ absorption bands, there were observed five fast ultraviolet emissions assigned to the 4f 1 5d→4f 2 transitions, and two long-wave bands corresponding to the f–f transitions. Furthermore, the intrinsic emission bands of SrCl 2 were observed at 10 K. The X-ray excited luminescence spectrum of the SrCl 2 :Pr crystal containing 0.2 mol% Pr, besides intrinsic emission band near 400 nm, has got a long-wave band at about 490 nm of the Pr 3+ centers. There were not observed any emission bands of the Pr 3+ centers corresponding to the 4f 1 5d–4f 2 transitions in the X-ray excited luminescence spectrum of the SrCl 2 :Pr crystal. The possible mechanisms of energy transfer from the SrCl 2 matrix to the Pr 3+ centers are discussed. -- Highlights: • Spectral-luminescent properties of SrCl 2 :Pr have been investigated. • The identification of emission 4f–4f and 5d–4f bands of Pr 3+ ions was performed. • Adding of potassium prevents clustering of the Pr 3+ centers in the SrCl 2 :Pr, K crystals. • Under X-ray excitation at 80–300 K only Pr 3+ 4f–4f and intrinsic emission is observed

Critical role of sphingosine-1-phosphate receptor 2 (S1PR2) in acute vascular inflammation.

Science.gov (United States)

Zhang, Guoqi; Yang, Li; Kim, Gab Seok; Ryan, Kieran; Lu, Shulin; O'Donnell, Rebekah K; Spokes, Katherine; Shapiro, Nathan; Aird, William C; Kluk, Michael J; Yano, Kiichiro; Sanchez, Teresa

2013-07-18

The endothelium, as the interface between blood and all tissues, plays a critical role in inflammation. Sphingosine-1-phosphate (S1P) is a bioactive sphingolipid, highly abundant in plasma, that potently regulates endothelial responses through interaction with its receptors (S1PRs). Here, we studied the role of S1PR2 in the regulation of the proadhesion and proinflammatory phenotype of the endothelium. By using genetic approaches and a S1PR2-specific antagonist (JTE013), we found that S1PR2 plays a key role in the permeability and inflammatory responses of the vascular endothelium during endotoxemia. Experiments with bone marrow chimeras (S1pr2(+/+) → S1pr2(+/+), S1pr2(+/+) → S1pr2(-/-), and S1pr2(-/-) → S1pr2(+/+)) indicate the critical role of S1PR2 in the stromal compartment, in the regulation of vascular permeability and vascular inflammation. In vitro, JTE013 potently inhibited tumor necrosis factor α-induced endothelial inflammation. Finally, we provide detailed mechanisms on the downstream signaling of S1PR2 in vascular inflammation that include the activation of the stress-activated protein kinase pathway that, together with the Rho-kinase nuclear factor kappa B pathway (NF-kB), are required for S1PR2-mediated endothelial inflammatory responses. Taken together, our data indicate that S1PR2 is a key regulator of the proinflammatory phenotype of the endothelium and identify S1PR2 as a novel therapeutic target for vascular disorders.

Effect of Pr6O11 doping in electrical and microstructural properties of SnO2-based varistors

Directory of Open Access Journals (Sweden)

Hervê Stangler Irion

2014-04-01

Full Text Available The influence of the dopant Pr6O11 was investigated with regard to the electrical and microstructural properties of the system (98.95-x%SnO2.1.0%CoO.0.05%Ta2O5.x%Pr6O11, where x = 0.05%, 0.10%, 0.30% and 0.50% in mol. Pr6O11 doping modifies the electrical behavior of the ceramics. The electrical parameters were: α = 8.0, EB = 319 V cm-1 and Vb = 0.66 V barrier-1 for the system without Pr6O11 and α = 17.0, EB = 853 V cm-1 and Vb = 1.15 V barrier-1 with the addition of 0.10% in mol Pr6O11. The system with 0.05% in mol Pr6O11 had the same non-linearity coefficient α as the system with 0.10% in mol. However, breakdown electrical field and voltage per barrier rates were lower (EB = 708 V cm-1 and Vb = 0.98 V barrier-1. The low rates in the breakdown electrical field enabled the varistor systems under study to be used in protection systems for low-voltage energy grids. In the case of Pr6O11 concentrations above 0.10% in mol, the presence of the dopant became deleterious to the varistor’s electrical characteristics. This effect was due to an increase in praseodymium stannate (Pr2Sn2O7 secondary phase. The crystalline phase coupled to the cassiterite (SnO2 phase was found with XRD and SEM/EDS and quantified by Rietveld’s refining method.

Ionic/Electronic Conductivity, Thermal/Chemical Expansion and Oxygen Permeation in Pr and Gd Co-Doped Ceria PrxGd0.1Ce0.9-xO1.95-δ

DEFF Research Database (Denmark)

Cheng, Shiyang; Chatzichristodoulou, Christodoulos; Søgaard, Martin

2017-01-01

Pr. A series of compositions of PrxGd0.1Ce0.9-xO1.95-δ (x = 0, 0.02, 0.05, 0.08, 0.15, 0.25, 0.3 and 0.4) was prepared by solid state reaction. X-ray powder diffraction (XPD) indicates that Pr is completely dissolved in the fluorite structure up to 40 at.%. Pronounced nonlinear thermal expansion...... behavior was observed as a function of temperature, due to the simultaneous contributions of both thermal and chemical expansion. The electronic and ionic conductivities were measured as a function of temperature and oxygen partial pressure. Within the range from 10 to 15 at.% Pr, a drastic drop...

Structural, magnetic and dielectric properties of Pr-modified BiFeO3 multiferroic

International Nuclear Information System (INIS)

Varshney, Dinesh; Sharma, Poorva; Satapathy, S.; Gupta, P.K.

2014-01-01

Graphical abstract: -- Highlights: • BFO and Bi 0.95 Pr 0.05 FeO 3 prepared successfully via solid state reaction route. • XRD confirms rhombohedral structure with space group R3c. • Relaxation process is attributed to thermal motion and hopping of V O 2+ . • Magnetization is enhanced in Bi 0.95 Pr 0.05 FeO 3 sample. • Enhanced magnetization stem from suppression of the spiral spin modulation. -- Abstract: The structural, vibrational, magnetic and dielectric properties of polycrystalline BiFeO 3 and Bi 0.95 Pr 0.05 FeO 3 are investigated by combining X-ray diffraction, Raman scattering spectra, magnetometry and dielectric measurements. Structural symmetry with rhombohedral R3c phase is revealed for both parent and 5% Pr substitution at Bi site, serving no chemical pressure and causes no structural transition from R3c to any other phase is identified from X-ray diffraction patterns and Raman scattering spectra. The shifting of phonon modes towards higher frequency side is attributed to lower atomic mass of Pr ion as compared to Bi ion. The magnetic measurements at room temperature indicate that Pr substitution induces ferromagnetism and discerns large and non-zero remnant magnetization as compare to pristine BiFeO 3 . Both dielectric permittivity and loss factor of Bi 0.95 Pr 0.05 FeO 3 strongly decreases with increased frequency. Significant role of hopping of oxygen ion vacancies in Bi 0.95 Pr 0.05 FeO 3 is inferred from modulus spectra and ac conductivity analysis

Electronic structures of PrBa{sub 2}Cu{sub 3}O{sub 7}, Pr{sub 2}Ba{sub 4}Cu{sub 7}O{sub 15-y}(y=0,1), and PrBa{sub 2}Cu{sub 4}O{sub 8} based on LSDA+U method

Energy Technology Data Exchange (ETDEWEB)

Tavana, A. [Magnet Research Laboratory (MRL), Department of Physics, Sharif University of Technology, Tehran (Iran); Department of Physics, University of Mohaghegh Ardabili, Ardabil (Iran); Shirazi, M.; Akhavan, M. [Magnet Research Laboratory (MRL), Department of Physics, Sharif University of Technology, Tehran (Iran)

2009-10-15

The electronic structures of PrBa{sub 2}Cu{sub 3}O{sub 7} (Pr123), Pr{sub 2}Ba{sub 4}Cu{sub 7}O{sub 15-y} (Pr247), and PrBa{sub 2}Cu{sub 4}O{sub 8} (Pr124) cuprates have been obtained using density-functional theory in the local spin density approximation plus onsite Coulomb interaction (LSDA+U). Onsite Hubbard correlation, U, has been considered for Pr-f and Cu-d orbitals and the effects of considering these correlation corrections on the Pr-O hybridizations have been inspected. Results imply that the Pr ionization state in Pr123 system is constituted from two different configurations, and the energy of the f states in these two configurations has an important role in superconductivity properties of the system. Our calculations also show that in both Pr124 and Pr247 systems, suppression of superconductivity is weaker than that in the Pr123 system. This occurs due to the weaker Pr-O bond in both Pr124 and Pr247 systems. The role of the double chain and single chain on the conduction properties of these compounds has been investigated. We have also studied the effect of oxygen deficiency in Pr247 system, which seems to revive superconductivity in this system. Investigating the hole carriers in the CuO{sub 2} plane shows a correlation between superconductivity suppression and hole decrement in the planes. (Abstract Copyright [2009], Wiley Periodicals, Inc.)

Luminescence dependence of Pr3+ activated SiO2 nanophosphor on Pr3+ concentration, temperature, and ZnO incorporation

CSIR Research Space (South Africa)

Mhlongo, GH

2011-08-01

Full Text Available Green-emitting ZnO nanoparticles were successfully embedded in Pr3+-doped SiO2 by a sol–gel method resulting in a red-emitting ZnO·SiO2:Pr3+ nanocomposite phosphor. The particle morphology and luminescent properties of SiO2:Pr3+ phosphor powders...

76 FR 5797 - Notice of Baseline Filings

Science.gov (United States)

2011-02-02

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. PR10-114-001; Docket No. PR10-129-001; Docket No. PR10-131- 001; Docket No. PR10-68-002 Not Consolidated] Notice of Baseline... applicants listed above submitted a revised baseline filing of their Statement of Operating Conditions for...

Word Frequency Analysis MOS: 95C. Skill Levels 1 & 2.

Science.gov (United States)

1981-05-01

EMTAEEN I Bt.ANKST 2 BLANK-. S 1 SLIND I BREA~ CNCD I EGICK I Of I flf.NG 2 BR~OKE N 1 BULBS t BLNK 2 aUtK. 2 BUT 14 By 3 C 9 C ,;LL I CALLS 4 CAN 1 C’O0... POLICIES 4 PCPULATION I PCta 7 PEP7.3m 3 PCSIT ION I POSSIBLE I FC!TS I I’!’!P .q I P.,FPsCRIBED 2 PkEt NCE I PRESENT 1 ppVi l I PR Iok 54 PR I SCNER

Electronic structure of layered ferroelectric high-k titanate Pr2Ti2O7

International Nuclear Information System (INIS)

Atuchin, V.V.; Gavrilova, T.A.; Grivel, J.-C.; Kesler, V.G.; Troitskaia, I.B.

2012-01-01

The spectroscopic parameters and electronic structure of binary titanate Pr 2 Ti 2 O 7 have been studied by IR-, Raman and X-ray photoelectron spectroscopy (XPS) for the powder sample prepared by solid state synthesis. The spectral features of valence band and all constituent element core levels have been considered. The Auger parameters of titanium and oxygen in Pr 2 Ti 2 O 7 have been determined as α Ti =872.8 and α O =1042.3 eV. Variations of cation–anion bond ionicity have been discussed using binding energy differences Δ Ti =(BE O 1s–BE Ti 2p 3/2 )=71.6 eV and Δ Pr =BE(Pr 3d 5/2 )−BE(O 1s)=403.8 eV as key parameters in comparison with those of other titanium- and praseodymium-bearing oxides. Highlights: ► Solid state synthesis of polar titanate Pr 2 Ti 2 O 7 . ► Structural and spectroscopic properties and electronic structure determination. ► Ti–O and Pr–O bonding analysis using Ti 2p 3/2 , Pr 3d 5/2 and O 1s core levels.

75 FR 70732 - Notice of Baseline Filings

Science.gov (United States)

2010-11-18

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. PR11-71-000; Docket No. PR11-72-000; Docket No. PR11-73- 000] Notice of Baseline Filings November 10, 2010. Docket No. PR11-71-000..., 2010, the applicants listed above submitted their baseline filing of their Statement of Operating...

9 CFR 95.2 - Region of origin.

Science.gov (United States)

2010-01-01

... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Region of origin. 95.2 Section 95.2... BYPRODUCTS (EXCEPT CASINGS), AND HAY AND STRAW, OFFERED FOR ENTRY INTO THE UNITED STATES § 95.2 Region of... Administrator, Veterinary Services, the name of the region of origin of such product or material: Provided, That...

Substitutions of PrP N-terminal histidine residues modulate scrapie disease pathogenesis and incubation time in transgenic mice.

Science.gov (United States)

Eigenbrod, Sabina; Frick, Petra; Bertsch, Uwe; Mitteregger-Kretzschmar, Gerda; Mielke, Janina; Maringer, Marko; Piening, Niklas; Hepp, Alexander; Daude, Nathalie; Windl, Otto; Levin, Johannes; Giese, Armin; Sakthivelu, Vignesh; Tatzelt, Jörg; Kretzschmar, Hans; Westaway, David

2017-01-01

Prion diseases have been linked to impaired copper homeostasis and copper induced-oxidative damage to the brain. Divalent metal ions, such as Cu2+ and Zn2+, bind to cellular prion protein (PrPC) at octapeptide repeat (OR) and non-OR sites within the N-terminal half of the protein but information on the impact of such binding on conversion to the misfolded isoform often derives from studies using either OR and non-OR peptides or bacterially-expressed recombinant PrP. Here we created new transgenic mouse lines expressing PrP with disrupted copper binding sites within all four histidine-containing OR's (sites 1-4, H60G, H68G, H76G, H84G, "TetraH>G" allele) or at site 5 (composed of residues His-95 and His-110; "H95G" allele) and monitored the formation of misfolded PrP in vivo. Novel transgenic mice expressing PrP(TetraH>G) at levels comparable to wild-type (wt) controls were susceptible to mouse-adapted scrapie strain RML but showed significantly prolonged incubation times. In contrast, amino acid replacement at residue 95 accelerated disease progression in corresponding PrP(H95G) mice. Neuropathological lesions in terminally ill transgenic mice were similar to scrapie-infected wt controls, but less severe. The pattern of PrPSc deposition, however, was not synaptic as seen in wt animals, but instead dense globular plaque-like accumulations of PrPSc in TgPrP(TetraH>G) mice and diffuse PrPSc deposition in (TgPrP(H95G) mice), were observed throughout all brain sections. We conclude that OR and site 5 histidine substitutions have divergent phenotypic impacts and that cis interactions between the OR region and the site 5 region modulate pathogenic outcomes by affecting the PrP globular domain.

Comparing the physical properties of Pr/Gd and Pr/Ce substitutions in Ru(Gd1.5Ce0.5)Sr2Cu2O10- δ

Science.gov (United States)

Khajehnezhad, A.; Nikseresht, N.; Hadipour, H.; Akhavan, M.

2008-06-01

We have compared the electrical and magnetic properties of Ru(Gd1.5- x Pr x )Ce0.5Sr2Cu2O10- δ (Pr/Gd samples) with x = 0.0, 0.01, 0.03, 0.033, 0.035, 0.04, 0.05, 0.06, 0.1 and RuGd1.5(Ce0.5- x Pr x ) Sr2 Cu2O10- δ (Pr/Ce samples) with x = 0.0, 0.01, 0.03, 0.05, 0.08, 0.1, 0.15, 0.2 prepared by the standard solid-state reaction technique. We obtained the XRD patterns for different samples with various x. The lattice parameters versus x for different substitutions have been obtained from Rietveld analysis. To determine how the magnetic and superconducting properties of these layered cuprate systems can be affected by Pr substitution, the resistivity, and magnetoresistivity, with H ext varying from 0.0 to 15 kOe, have been measured at various temperatures. Superconducting transition temperature T c and magnetic transition T irr , have been obtained through resistivity and ac susceptibility measurements. The T c suppression due to Pr/Gd and Pr/Ce substitutions show competition between pair breaking by magnetic impurities, hole doping due to different valances of ions, difference in ionic radii, and oxygen stoichiometry. Pr/Gd substitution suppresses superconductivity more rapidly than for Pr/Ce, showing that the effect of hole doping and magnetic impurity pair breaking is stronger than the difference in ionic radii. In Pr/Gd substitution, the small difference between the ionic radii of Pr3+,4+ and Gd3+, and absorption of more oxygen due to the higher valence of Pr with respect to Gd, decreases the mean Ru-Ru distance, and as a result, the magnetic exchange interaction becomes stronger with the increase of x. However, Pr/Ce substitution has the opposite effect. The magnetic parameters such as H c , obtained through magnetization measurements versus applied magnetic field isotherm at 77 K and room temperatures, become stronger with x in Pr/Gd and weaker with x in Pr/Ce substitution.

Structural, magnetic, and electronic transport properties of pyrochlore iridate Pr2Ir2O7

Science.gov (United States)

Kumar, Harish; Chaurasia, Rachna; Kumari, Pratibha; Paramanik, A. K.

2018-04-01

We have studied the structural, magnetic, and electronic transport properties of pyrochlore iridate Pr2Ir2O7. Structural investigation has been done using x-ray powder diffraction and Rietveld analysis. Pr2Ir2O7 crystallize in cubic crystallographic phase with Fd-3m space group. Temperature dependent magnetization data does not show magnetic bifurcation down to 2 K. Electrical resistivity data of Pr2Ir2O7 exhibits metallic behavior throughout temperature range. Below 50 K, a small rise in resistivity data of Pr2Ir2O7 is observed down to 12 K.

75 FR 57268 - Notice of Baseline Filings

Science.gov (United States)

2010-09-20

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. PR10-103-000; Docket No. PR10-104-000; Docket No. PR10-105- 000 (Not Consolidated)] Notice of Baseline Filings September 13..., 2010, and September 10, 2010, respectively the applicants listed above submitted their baseline filing...

76 FR 78640 - Hattiesburg Industrial Gas Sales, L.L.C.; Notice of Filing

Science.gov (United States)

2011-12-19

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket Nos. PR12-8-000 and PR12-9-000] Hattiesburg Industrial Gas Sales, L.L.C.; Notice of Filing Take notice that on December 9, 2011, Hattiesburg Industrial Gas Sales, L.L.C. (Hattiesburg) filed in PR12-8-000 a Statement of Operating Conditions (SOC) with...

Crystal growth and scintillation properties of Pr-doped SrI2 single crystals

Science.gov (United States)

Yokota, Yuui; Ito, Tomoki; Yoshino, Masao; Yamaji, Akihiro; Ohashi, Yuji; Kurosawa, Shunsuke; Kamada, Kei; Yoshikawa, Akira

2018-04-01

Pr-doped SrI2 (Pr:SrI2) single crystals with various Pr concentrations were grown by the halide-micro-pulling-down (H-μ-PD) method, and the scintillation properties were investigated. Pr1%:SrI2 single crystal with high transparency could be grown by the H-μ-PD method while Pr2, 3 and 5%:SrI2 single crystals included some cracks and opaque parts. In the photoluminescence spectrum of the Pr1%:SrI2 single crystal, an emission peak originated from the Pr3+ ion was observed around 435 nm while the radioluminescence spectra showed an emission peak around 535 nm for the undoped SrI2 and Pr:SrI2 single crystals. Light yields of Pr1, 2, 3 and 5%:SrI2 single crystals under γ-ray irradiation were 7700, 8700, 7200 and 6700 photons/MeV, respectively. Decay times of Pr1 and 2%:SrI2 single crystals under γ-ray irradiation were 55.9 and 35.0 ns of the fast decay component, and 435 and 408 ns of the slow decay component, respectively.

77 FR 63311 - Acacia Natural Gas Corporation; Notice of Petition for Rate Approval

Science.gov (United States)

2012-10-16

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. PR13-1-000] Acacia Natural Gas Corporation; Notice of Petition for Rate Approval Take notice that on October 9, 2012, Acacia Natural Gas Corporation (Acacia) filed a Petition for Rate Approval pursuant to 284.123(b)(2) of the...

76 FR 13610 - Enterprise Texas Pipeline LLC; Notice of Compliance Filing

Science.gov (United States)

2011-03-14

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket Nos. PR10-14-002; PR11-92-000] Enterprise Texas Pipeline LLC; Notice of Compliance Filing Take notice that on March 1, 2011, Enterprise Texas Pipeline LLC (Enterprise Texas) filed a revised Statement of Rates to its Statement of Operating...

Major enhancement of the thermoelectric performance in Pr/Nb-doped SrTiO3 under strain

KAUST Repository

Amin, B.

2013-07-16

The electronic structure and thermoelectric properties of strained (biaxially and uniaxially) Sr0.95Pr0.05TiO3 and SrTi0.95Nb0.05O3 are investigated in the temperature range from 300 K to 1200 K. Substitutions of Pr at the Sr site and Nb at the Ti site generate n-type doping and thus improve the thermoelectric performance as compared to pristine SrTiO3. Further enhancement is achieved by the application of strain, for example, of the Seebeck coefficient by 21% for Sr0.95Pr0.05TiO3 and 10% for SrTi0.95Nb0.05O3 at room temperature in the case of 5% biaxial strain. At 1200 K, we predict figures of merit of 0.58 and 0.55 for 2.5% biaxially strained Sr0.95Pr0.05TiO3 and SrTi0.95Nb0.05O3 , respectively, which are the highest values reported for rare earth doped SrTiO3.

Electronic structure of layered ferroelectric high-k titanate Pr2Ti2O7

Science.gov (United States)

Atuchin, V. V.; Gavrilova, T. A.; Grivel, J.-C.; Kesler, V. G.; Troitskaia, I. B.

2012-11-01

The spectroscopic parameters and electronic structure of binary titanate Pr2Ti2O7 have been studied by IR-, Raman and X-ray photoelectron spectroscopy (XPS) for the powder sample prepared by solid state synthesis. The spectral features of valence band and all constituent element core levels have been considered. The Auger parameters of titanium and oxygen in Pr2Ti2O7 have been determined as αTi=872.8 and αO=1042.3 eV. Variations of cation-anion bond ionicity have been discussed using binding energy differences ΔTi=(BE O 1s-BE Ti 2p3/2)=71.6 eV and ΔPr=BE(Pr 3d5/2)-BE(O 1s)=403.8 eV as key parameters in comparison with those of other titanium- and praseodymium-bearing oxides.

Prática de futebol e fatores sociodemográficos associados em adolescentes La práctica de fútbol y factores sociodemográficos asociados en adolescentes Soccer practice and associated sociodemographic factors in adolescents

Directory of Open Access Journals (Sweden)

Diego Augusto Santos Silva

2013-03-01

Full Text Available Objetivou-se verificar a associação entre a prática de futebol com fatores sociodemográficos em escolares. A amostra foi composta por 906 estudantes de escolas públicas de Aracaju, Sergipe, Brasil, com média de 15,11 (DP=2,19 anos de idade. Utilizou-se a regressão de Poisson para o cálculo da razão de prevalência (RP e intervalos de confiança de 95% (IC95%. Dos estudantes investigados, 49,1% não praticavam futebol. Os escolares com maiores probabilidades de não praticar futebol foram os do sexo feminino (RP: 3,28; IC95%: 2,59-4,15 e do ensino médio (RP: 1,45; IC95%: 1,10-1,92. Quase metade dos estudantes não pratica futebol e, independente da faixa etária e nível econômico, em estudantes do sexo feminino e do ensino médio a probabilidade de prática na modalidade é ainda menor.Este estudio evaluó la asociación entre la práctica de fútbol con factores sociodemográficos en los escolares. La muestra está compuesta por 906 estudiantes de escuelas públicas en Aracaju, Sergipe, Brasil, con una media de 15,11 (SD = 2,19 años de edad. Se utilizó la regresión de Poisson para el cálculo de la tasa de prevalencia (RP y los intervalos de confianza del 95% (IC95%. De los estudiantes encuestados, el 49,1% no practica el fútbol. Los niños con más probabilidades de no jugar al fútbol eran mujeres (RP: 3,28, IC95%: 2,59 a 4,15 y de la escuela secundaria (RP: 1,45, IC95%: 1,10 - 1,92. Casi la mitad de los estudiantes no practican el fútbol y sin importar la edad y el nivel económico, las alumnas y los alumnos de la escuela secundaria probablemente a la práctica en el deporte es aún menor.The objective of this study was to evaluate the association between soccer practice and sociodemographic factors in adolescents. The sample consisted of 906 public school students from Aracaju, Sergipe, Brazil, with a mean age of 15.11 (SD=2.19 years. Poisson regression was used to calculate the prevalence ratio (PR and 95% confidence

75 FR 41855 - Enogex L.L.C.; Notice of Petition for Rate Approval

Science.gov (United States)

2010-07-19

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. PR10-52-000] Enogex L.L.C.; Notice of Petition for Rate Approval July 13, 2010. Take notice that on July 1, 2010, Enogex L.L.C. (Enogex) filed pursuant to section 284.123(b)(2) of the Commission's regulations, filed a petition...

Poppers and PrEP: Use of Pre-exposure Prophylaxis Among Men Who Have Sex with Men Who Use Inhaled Nitrites.

Science.gov (United States)

Hambrick, H Rhodes; Park, Su Hyun; Schneider, John A; Mayer, Kenneth H; Carrico, Adam W; Sherman, Scott E; Duncan, Dustin T

2018-05-09

Men who have sex with men (MSM) commonly use inhaled nitrites, or poppers, though their use is a risk factor HIV seroconversion. Pre-exposure prophylaxis, or PrEP, is effective for HIV prevention, but is not widely used, and little is known regarding PrEP use and acceptability among MSM who use inhaled nitrites. We surveyed 580 MSM in Paris, France in 2016 about popper use, sexual behaviors including condomless anal intercourse (CAI), serosorting, and sexual positioning, PrEP use, PrEP candidacy, and interest in alternate PrEP delivery modalities. We included 444 HIV negative participants for the current study. 46.2% reported popper use in the prior 3 months. Using multivariate adjusted logistic regression, we found that popper users were more likely than non-users to consider themselves candidates for PrEP [adjusted relative risk ratio (aRRR) = 2.73; 95% CI 1.54-4.83], but they were not more likely to be current (aRRR = 1.54; 95% CI 0.71-3.33) or past (aRRR = 1.37; 95% CI 0.44-4.28) PrEP users. Mediation analyses indicated that increased CAI and serosorting partly explained the relationship between popper use and PrEP candidacy. There was considerable interest in alternate proposed PrEP delivery modalities, particularly long-acting injectable PrEP [adjusted risk ratio (aRR) = 1.43; 95% CI 1.15-1.79].

28 CFR 2.95 - Early termination from supervision.

Science.gov (United States)

2010-07-01

... 28 Judicial Administration 1 2010-07-01 2010-07-01 false Early termination from supervision. 2.95 Section 2.95 Judicial Administration DEPARTMENT OF JUSTICE PAROLE, RELEASE, SUPERVISION AND RECOMMITMENT OF PRISONERS, YOUTH OFFENDERS, AND JUVENILE DELINQUENTS District of Columbia Code: Prisoners and Parolees § 2.95 Early termination from...

Electronic structure of PrBa2Cu3O7

International Nuclear Information System (INIS)

Singh, D.J.

1994-01-01

Electronic-structure calculations, within the local spin density approximation (LSDA), are reported for PrBa 2 Cu 3 O 7 . Significant charge transfer from the Pr ions to both the CuO 2 planes and the chains is found relative to YBa 2 Cu 3 O 7 . This supports hole depletion explanations for the insulating character of PrBa 2 Cu 3 O 7 . The LSDA electronic structure shows a prominent ''ridge'' Fermi surface analogous to that in YBa 2 Cu 3 O 7 , but broader. It is proposed that high-resolution positron measurements of this width may provide a useful test of hole depletion models

Anomalous properties of PrBa2Cu3O7: a comment

International Nuclear Information System (INIS)

Sampathkumaran, E.V.

1992-01-01

Considerable attention has been paid in the literature to understand the suppression of superconductivity and the large Neel temperature of the Pr sub-lattice in PrBa 2 Cu 3 O 7 . Here we briefly recall the superconducting and magnetic anomalies noted earlier in other Pr based systems due to the partial delocalisation of the Pr-4f orbital to show that the gross anomalous features observed for PrBa 2 Cu 4 O 7 are not unique. (orig.)

Crystal Growth and Neutron Scattering Study of Spin Correlations of the T‧-Structured Pr2‑x Ca x CuO4

Science.gov (United States)

Fujita, Masaki; Tsutsumi, Kenji; Miura, Tomohiro; Danilkin, Sergey

2018-03-01

We studied Ca-doping effect on spin correlations in T‧-structured cuprate oxide RE2CuO4 (RE: rear earth) with growing a sizable single crystal of Pr2‑x Ca x CuO4 (x=0.05 and 0.10) as well as synthesizing powder samples of Pr1.90Ca0.10CuO4 and Eu1.90Ca0.10CuO4. In the all as-prepared and annealed samples, no evidence of shielding signal associated with superconductivity was observed by magnetic susceptibility measurement. Elastic neutron scattering measurements on the as-grown Pr1.90Ca0.10CuO4 clarified the existence of long-ranged magnetic order with commensurate spin correlation. The ordering temperature was determined to be ∼290K, which is comparable to Néel temperature in the parent compound of Pr2CuO4. The existence of commensurate low-energy spin excitation was also confirmed by inelastic neutron scattering measurements for the annealed Pr1.95Ca0.05CuO4. These results strongly suggest a negligible Ca-doping effect on the physical properties in T‧-RE2CuO4, which is quite different from the drastic doping evolution of magnetism in T -RE2CuO4.

7 CFR 2.95 - Director, Office of Ethics.

Science.gov (United States)

2010-01-01

... 7 Agriculture 1 2010-01-01 2010-01-01 false Director, Office of Ethics. 2.95 Section 2.95... Administration § 2.95 Director, Office of Ethics. The Director, Office of Ethics, shall be the USDA Alternate Agency Ethics Official, pursuant to 5 CFR 2638.202, and shall exercise the authority reserved to the...

Synthesis and characterization of praseodymium-142 hydroxyapatite (142Pr-HA)

International Nuclear Information System (INIS)

Duyeh Setiawan; Daud Nurhasan

2015-01-01

The use of radioisotope of lanthanide group with range of beta energy 0.4 - 2.2 MeV has been renewed interest in nuclear medicine. Praseodymium-142 radioisotope ( 142 Pr, t 1/2 = 19.2 hours, E β = 2.16 MeV) is suitable for applications radiotherapy. Labelled of the hydroxyapatite (Ca 10 (PO 4 )6(OH) 2 ) can be used as carrier of radionuclide after injection in the body injection. This research aim as a preliminary studies to make praseodymium-142 hydroxyapatite ( 142 Pr-HA) as a radiotherapy agent. The optimum condition of praseodymium-142 hydroxyapatite synthesis by controlling several parameters such as the pH and the weight of hydroxyapatite was obtained from process by used the nonradioactive praseodymium. The optimum condition of hydroxyapatite by praseodymium are at pH 5 and weight ratio praseodymium : hydroxyapatite is 1 : 16. The percentage of labeling hydroxyapatite with 142 PrCl 3 was 99.50% and the radiochemical purity of 142 Pr-Ha was 95.20%. (author)

Exploring the crystallization landscape of cadmium bis(N-hydroxyethyl, N-isopropyldithiocarbamate), Cd[S2CN(iPr)CH2CH2OH]2

International Nuclear Information System (INIS)

Tan, Yee Seng; Halim, Siti Nadiah Abdul; Tiekink, Edward R.T.; Sunway Univ., Bandar Sunway

2016-01-01

Crystallization of Cd[S 2 CN(iPr)CH 2 CH 2 OH] 2 from ethanol yields the coordination polymer [{Cd[S 2 CN(iPr)CH 2 CH 2 OH] 2 }.EtOH] ∞ (1) within 3 h. When the solution is allowed to stand for another hour, the needles begin to dissolve and prisms emerge of the supramolecular isomer (SI), binuclear {Cd[S 2 CN(iPr)CH 2 CH 2 OH] 2 } 2 .2EtOH (2). These have been fully characterized spectroscopically and by X-ray crystallography. Polymeric 1 has 2-fold symmetry and features dithiocarbamate ligands coordinating two octahedral Cd atoms in a μ 2 κ 2 -tridentate mode. Binuclear 2 is centrosymmetric with two ligands being μ 2 κ 2 -tridentate as for 1 but the other two being κ 2 -chelating leading to square pyramidal geometries. The conversion of the kinetic crystallization product, 1, to thermodynamic 2 is irreversible but transformations mediated by recrystallization (ethanol and acetonitrile) to related literature SI species, namely coordination polymer [{Cd[S 2 CN(iPr)CH 2 CH 2 OH] 2 } 3 .MeCN] ∞ and binuclear {Cd[S 2 CN(iPr)CH 2 CH 2 OH] 2 } 2 .2H 2 O.2MeCN, are demonstrated, some of which are reversible. Three other crystallization outcomes are described whereby crystal structures were obtained for the 1:2 co-crystal {Cd[S 2 CN(iPr)CH 2 CH 2 OH] 2 } 2 :2[3-(propan-2-yl)-1,3-oxazolidine-2-thione] (3), the salt co-crystal [iPrNH 2 (CH 2 CH 2 OH)] 4 [SO 4 ] 2 {Cd[S 2 CN(iPr)CH 2 CH 2 OH] 2 } 2 (4) and the salt [iPrNH 2 (CH 2 CH 2 OH)]{Cd[S 2 CN(iPr)CH 2 CH 2 OH] 3 } (5). These arise as a result of decomposition/oxidation of the dithiocarbamate ligands. In each of 3 and 4 the binuclear {Cd[S 2 CN(iPr)CH 2 CH 2 OH] 2 } 2 SI, as in 2, is observed strongly suggesting a thermodynamic preference for this form.

75 FR 79334 - Meeting Notice

Science.gov (United States)

2010-12-20

... ARCTIC RESEARCH COMMISSION Meeting Notice Notice is hereby given that the U.S. Arctic Research Commission will hold its 95th meeting in Anchorage, AK, on January 21, 2011. The business session, open to... agenda. (2) Approval of the minutes from the 94th meeting. (3) Commissioners and staff reports. (4...

Electronic structure of layered ferroelectric high-k titanate Pr{sub 2}Ti{sub 2}O{sub 7}

Energy Technology Data Exchange (ETDEWEB)

Atuchin, V.V., E-mail: atuchin@thermo.isp.nsc.ru [Laboratory of Optical Materials and Structures, Institute of Semiconductor Physics, SB RAS, Novosibirsk 90, 630090 (Russian Federation); Gavrilova, T.A. [Laboratory of Nanodiagnostics and Nanolithography, Institute of Semiconductor Physics, SB RAS, Novosibirsk 90, 630090 (Russian Federation); Grivel, J.-C. [Materials Research Division, National Laboratory for Sustainable Energy, Technical University of Denmark, Frederiksborgvej 399, DK-4000, Roskilde (Denmark); Kesler, V.G. [Laboratory of Physical Bases of Integrated Microelectronics, Institute of Semiconductor Physics, SB RAS, Novosibirsk 90, 630090 (Russian Federation); Troitskaia, I.B. [Laboratory of Optical Materials and Structures, Institute of Semiconductor Physics, SB RAS, Novosibirsk 90, 630090 (Russian Federation)

2012-11-15

The spectroscopic parameters and electronic structure of binary titanate Pr{sub 2}Ti{sub 2}O{sub 7} have been studied by IR-, Raman and X-ray photoelectron spectroscopy (XPS) for the powder sample prepared by solid state synthesis. The spectral features of valence band and all constituent element core levels have been considered. The Auger parameters of titanium and oxygen in Pr{sub 2}Ti{sub 2}O{sub 7} have been determined as {alpha}{sub Ti}=872.8 and {alpha}{sub O}=1042.3 eV. Variations of cation-anion bond ionicity have been discussed using binding energy differences {Delta}{sub Ti}=(BE O 1s-BE Ti 2p{sub 3/2})=71.6 eV and {Delta}{sub Pr}=BE(Pr 3d{sub 5/2})-BE(O 1s)=403.8 eV as key parameters in comparison with those of other titanium- and praseodymium-bearing oxides. Highlights: Black-Right-Pointing-Pointer Solid state synthesis of polar titanate Pr{sub 2}Ti{sub 2}O{sub 7}. Black-Right-Pointing-Pointer Structural and spectroscopic properties and electronic structure determination. Black-Right-Pointing-Pointer Ti-O and Pr-O bonding analysis using Ti 2p{sub 3/2}, Pr 3d{sub 5/2} and O 1s core levels.

PR Interval Prolongation and Cryptogenic Stroke: A Multicenter Retrospective Study.

Science.gov (United States)

Montalvo, Mayra; Tadi, Prasanna; Merkler, Alexander; Gialdini, Gino; Martin-Schild, Sheryl; Navalkele, Digvijaya; Samai, Alyana; Nouh, Amre; Hussain, Mohammad; Goldblatt, Steven; Hemendinger, Morgan; Chu, Antony; Song, Christopher; Kamel, Hooman; Furie, Karen L; Yaghi, Shadi

2017-10-01

Atrial dysfunction or "cardiopathy" has been recently proposed as a mechanism in cryptogenic stroke. A prolonged PR interval may reflect impaired atrial conduction and thus may be a biomarker of atrial cardiopathy. We aim to compare the prevalence of PR interval prolongation in patients with cryptogenic stroke (CS) when compared with known non-cryptogenic non-cardioembolic stroke (NCNCS) subtypes. We used prospective ischemic stroke databases of 3 comprehensive stroke centers to identify patients 18 years or older with a discharge diagnosis of ischemic non-cardioembolic stroke between December 1, 2013 and August 31, 2015. The main outcome was ischemic stroke subtype (CS versus NCNCS). We compared PR intervals as a continuous and categorical variable (PR interval prolongation and CS. We identified 644 patients with ischemic non-cardioembolic stroke (224 CS and 420 NCNCS). Patients with CS were more likely to have a PR of 200 milliseconds or greater when compared with those with NCNCS (23.2% versus 13.8%, P = .009). After adjusting for factors that were significant in univariate analyses, a PR of 200 milliseconds or greater was independently associated with CS (odds ratio [OR] 1.70, 95% CI 1.08-2.70). The association was more pronounced when excluding patients on atrioventricular nodal blocking agents (OR 2.64, 95% CI 1.44-4.83). A PR of 200 milliseconds or greater is associated with CS and may be a biomarker of atrial cardiopathy in the absence of atrial fibrillation. Prospective studies are needed to confirm this association. Copyright © 2017 National Stroke Association. Published by Elsevier Inc. All rights reserved.

Crystal structure of NaPr(SeO4)2

International Nuclear Information System (INIS)

Ovanisyan, S.M.; Iskhakova, L.D.

1989-01-01

NaPr(SeO 4 ) 2 structure is decoded (autodiffractometer CAD-4). Triclinic cell parameters are as follows: a=6.639(2), b=7.118(1), c=7.36(1) A, α=99.16(2) deg, β=96.93(2) deg, γ=89.77 (3) deg, p.gr. P1-bar, Z=2. Structure is of carcass type, built on CaSO 4 anhydride structure base with 2Ca→TR 3+ +Na + -type ordered substitution. Structural comparative crystallochemical analysis of anhydride and NaPr(SeO 4 ) 2 and NaNd(SO 4 ) 2 isostructural double salts is carried out

76 FR 23642 - Culturally Significant Objects Imported for Exhibition Determinations: “Projects 95: Runa Islam”

Science.gov (United States)

2011-04-27

... DEPARTMENT OF STATE [Public Notice: 7433] Culturally Significant Objects Imported for Exhibition Determinations: ``Projects 95: Runa Islam'' SUMMARY: Notice is hereby given of the following determinations... the exhibition ``Projects 95: Runa Islam'' imported from abroad for temporary exhibition within the...

High performance and highly durable infiltrated cathodes using Pr-modified Ce_0.9Gd_0.1O_1.95 backbone

DEFF Research Database (Denmark)

Samson, Alfred Junio; Søgaard, Martin; Bonanos, Nikolaos

2014-01-01

°C (without Pr: Rp from 0.094 to 0.45 Ω cm2, Rs from 0.74 to 0.79 Ω cm2; with Pr: Rp from 0.051 to 0.32 Ω cm2, Rs from 0.74 to 0.71 Ω cm2). The improved performance and heat treatment tolerance is thought to originate from the imparted electronic conductivity into the CGO backbone by introducing Pr....

Bulk modulus of CeO2 and PrO2-An experimental and theoretical study

International Nuclear Information System (INIS)

Gerward, L.; Staun Olsen, J.; Petit, L.; Vaitheeswaran, G.; Kanchana, V.; Svane, A.

2005-01-01

The high-pressure structural behaviour of CeO 2 and PrO 2 has been investigated by synchrotron X-ray diffraction at pressures up to 20 and 35 GPa, respectively. The experiments are accompanied by first principles calculations using the self-interaction corrected local spin density (SIC-LSD) approximation. The experimental values for the zero-pressure bulk modulus of CeO 2 and PrO 2 are 220(9) and 187(8) GPa, respectively. Our calculations reproduce the lattice constants with good accuracy, but find identical bulk modulii for CeO 2 (176.9 GPa) and PrO 2 (176.8 GPa)

MoTe2 saturable absorber for passively Q-switched Ho,Pr:LiLuF4 laser at ∼3 μm

Science.gov (United States)

Yan, Zhengyu; Li, Tao; Zhao, Shengzhi; Yang, Kejian; Li, Dechun; Li, Guiqiu; Zhang, Shuaiyi; Gao, Zijing

2018-03-01

Multilayer molybdenum ditelluride (MoTe2) nanosheets were prepared by liquid-phase exfoliation (LPE) method. A YAG-based MoTe2 saturable absorption (SA) was consequently fabricated. The MoTe2-SA was employed in a passively Q-switched Ho,Pr:LiLuF4 laser at 2.95 μm. Under the absorbed pump power of 3.8 W, an average output power of 90 mW was achieved. The shortest pulse duration of 670 ns was generated with an output power of 73 mW and a repetition rate of 76.46 kHz, corresponding to a pulse energy of 0.95 μJ.

76 FR 70438 - Enterprise Intrastate L.P., Enterprise Texas Pipeline LLC; Notice of Filing

Science.gov (United States)

2011-11-14

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. PR12-4-000; Docket No. PR12-5-000; Not Consolidated] Enterprise Intrastate L.P., Enterprise Texas Pipeline LLC; Notice of Filing Take notice that on November 1, 2011, the applicants listed above filed a revised Statement of...

Beyond PrPres Type 1/Type 2 Dichotomy in Creutzfeldt-Jakob Disease

Science.gov (United States)

Simon, Stéphanie; Lugan, Séverine; Bilheude, Jean-Marc; Perret-Liaudet, Armand; Ironside, James W.; Haik, Stéphane; Basset-Leobon, Christelle; Lacroux, Caroline; Peoch', Katell; Streichenberger, Nathalie; Langeveld, Jan; Head, Mark W.; Grassi, Jacques; Hauw, Jean-Jacques; Schelcher, Francois; Delisle, Marie Bernadette; Andréoletti, Olivier

2008-01-01

Sporadic Creutzfeldt-Jakob disease (sCJD) cases are currently subclassified according to the methionine/valine polymorphism at codon 129 of the PRNP gene and the proteinase K (PK) digested abnormal prion protein (PrPres) identified on Western blotting (type 1 or type 2). These biochemically distinct PrPres types have been considered to represent potential distinct prion strains. However, since cases of CJD show co-occurrence of type 1 and type 2 PrPres in the brain, the basis of this classification system and its relationship to agent strain are under discussion. Different brain areas from 41 sCJD and 12 iatrogenic CJD (iCJD) cases were investigated, using Western blotting for PrPres and two other biochemical assays reflecting the behaviour of the disease-associated form of the prion protein (PrPSc) under variable PK digestion conditions. In 30% of cases, both type 1 and type 2 PrPres were identified. Despite this, the other two biochemical assays found that PrPSc from an individual patient demonstrated uniform biochemical properties. Moreover, in sCJD, four distinct biochemical PrPSc subgroups were identified that correlated with the current sCJD clinico-pathological classification. In iCJD, four similar biochemical clusters were observed, but these did not correlate to any particular PRNP 129 polymorphism or western blot PrPres pattern. The identification of four different PrPSc biochemical subgroups in sCJD and iCJD, irrespective of the PRNP polymorphism at codon 129 and the PrPres isoform provides an alternative biochemical definition of PrPSc diversity and new insight in the perception of Human TSE agents variability. PMID:18389084

Anomalous Schottky specific heat and structural distortion in ferromagnetic PrAl2.

Science.gov (United States)

Pathak, Arjun K; Paudyal, D; Mudryk, Y; Gschneidner, K A; Pecharsky, V K

2013-05-03

Unique from other rare earth dialuminides, PrAl(2) undergoes a cubic to tetragonal distortion below T = 30 K in a zero magnetic field, but the system recovers its cubic symmetry upon the application of an external magnetic field of 10 kOe via a lifting of the 4f crystal field splitting. The nuclear Schottky specific heat in PrAl(2) is anomalously high compared to that of pure Pr metal. First principles calculations reveal that the 4f crystal field splitting in the tetragonally distorted phase of PrAl(2) underpins the observed unusual low temperature phenomena.

Scintillation properties of μPD-grown Y{sub 4}Al{sub 2}O{sub 9}:Pr (YAM:Pr) crystals

Energy Technology Data Exchange (ETDEWEB)

Drozdowski, Winicjusz, E-mail: wind@fizyka.umk.pl [Institute of Physics, Faculty of Physics, Astronomy and Informatics, Nicolaus Copernicus University, Grudziadzka 5, 87-100 Torun (Poland); Brylew, Kamil [Institute of Physics, Faculty of Physics, Astronomy and Informatics, Nicolaus Copernicus University, Grudziadzka 5, 87-100 Torun (Poland); Malinowski, Michał [Institute of Microelectronics and Optoelectronics, Koszykowa 75, 00-662 Warsaw (Poland); Turczyński, Sebastian [Institute of Electronic Materials Technology, Wolczynska 133, 01-919 Warsaw (Poland)

2015-05-25

Highlights: • YAM:Pr crystals do scintillate and as such deserve further interest. • Fast d–f luminescence of Pr{sup 3+} ions appears in X-ray excited spectra. • Two components (24 and 790 ns) constitute scintillation time profiles. - Abstract: Y{sub 4}Al{sub 2}O{sub 9}:Pr (YAM:Pr) crystals have been grown by the micro-pulling-down method and their scintillation properties have been investigated. YAM:0.1%Pr displays a light yield of about 2000 ph/MeV and its scintillation time profile contains a prompt component with a decay time of 23.5 ns and a contribution of 20%. Radioluminescence spectra show both fast d–f and slow f–f praseodymium emissions. Low temperature glow curves are complex, consisting of discrete peaks and broad bands related to quasi-continuous trap distributions. Overall scintillation performance of YAM:Pr deteriorates with increasing praseodymium concentration.

75 FR 65467 - Enterprise Alabama Intrastate, LLC; Enterprise Intrastate L.P; Notice of Baseline Filings

Science.gov (United States)

2010-10-25

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. PR11-4-000; Docket No. PR11-5-000; Not Consolidated] Enterprise Alabama Intrastate, LLC; Enterprise Intrastate L.P; Notice of Baseline Filings October 18, 2010. Take notice that on October 15, 2010, the applicants listed above...

Magnetic order in PrBa2Cu3O6+x

DEFF Research Database (Denmark)

Longmore, A.; Nutley, M.P.; Boothroyd, A.T.

1994-01-01

We have studied the magnetic ordering of the Cu and Pr ions in PrBa2Cu3O6+x by neutron diffraction on single crystals with different oxygen contents. Two types of Cu ordering were observed, qualitatively similar to the anti-ferromagnetic phases reported in some studies of YBa2Cu3O6+x. A third...... magnetic structure was observed below 15K, which we believe corresponds to the magnetic ordering of the Pr sub-lattice....

Incommensurate magnetism in PrBa2Cu3O6.92

DEFF Research Database (Denmark)

Hill, J.P.; Boothroyd, A.T.; Andersen, N.H.

1998-01-01

We report resonant x-ray magnetic scattering and high-resolution neutron-diffraction studies of the Pr site magnetism in high quality single crystals of PrBa2Cu3O6.92. These studies reveal that the Pr sublattice orders at 19 K in a well correlated, long period incommensurate structure with probable...

Pr and Gd co-doped bismuth ferrite thin films with enhanced

Indian Academy of Sciences (India)

Pr and Gd co-modified Bi0.95−PrGd0.05FeO3 ( = 0.00, 0.05, 0.10) (BPGFO) thin films on Pt(111)/Ti/SiO2/Si(100) substrates were prepared by a sol-gel together with spin coating technique. A detailed study of electrical and magnetic properties of these thin films is reported. X-ray diffraction analysis shows that, with an ...

Pr2Fe14B/α-Fe nanocomposites for thermal applications

International Nuclear Information System (INIS)

Silva, Suelanny Carvalho da

2012-01-01

In this work, Pr x Fe 94 - x B 6 (x = 6, 8, 10 and 12) nanostructured powders were prepared by a combination of hydrogenation, disproportionation, desorption and recombination (HDDR) process with high energy milling applied to the mixture of an as-cast alloy (Pr 14 Fe 80 B 6 ) and α-Fe. The produced nanoparticles showed magnetic properties comparable to those reported in hyperthermia studies. The optimal time to obtain the magnetic nanoparticles is 5 hours (at 900 rpm). It was verified that longer milling times cause an increase in carbon percentage on the particles. The carbon is derived from oleic acid added as a surfactant in the milling step. The nanocomposites exhibit coercive force ranging from 80 Oe (6.5 kAm -1 ) to 170 Oe (13.5 kAm -1 ) and magnetic moments in the range of 81 129 Am2kg -1 . From the X-ray diffraction analyses, only two phases were found in all samples: α-Fe and the magnetic phase Pr 2 Fe 14 B. Individual nanoparticles with diameter of about 20 nm were verified. The samples studied presented heating when exposed to an alternating magnetic field (f = 222 kHz e H max ∼3.7 kAm -1 ) comparable to reported in literature. Temperature variations (ΔT) of the powders were: 51 K for Pr 6 Fe 88 B 6 , 41 K for Pr 8 Fe 86 B 6 , 38 K for Pr 10 Fe 8 4 B 6 and T = 34 K for Pr 12 Fe 82 B 6 . The specific absorption rates (SARs) of the powders were 201 Wkg -1 for Pr 6 Fe 88 B 6 composition, 158 Wkg -1 on the composition Pr 8 Fe 86 B 6 , and 114 Wkg -1 for Pr 10 Fe 84 B 6 and Pr 12 Fe 82 B 6 compositions. (author)

Heterometallic cerium(IV) perrhenate, permanganate, and molybdate complexes supported by the imidodiphosphinate ligand [N(i-Pr2PO)2]-.

Science.gov (United States)

Wang, Guo-Cang; Sung, Herman H Y; Dai, Feng-Rong; Chiu, Wai-Hang; Wong, Wai-Yeung; Williams, Ian D; Leung, Wa-Hung

2013-03-04

Heterometallic cerium(IV) perrhenate, permanganate, and molybdate complexes containing the imidodiphosphinate ligand [N(i-Pr2PO)2](-) have been synthesized, and their reactivity was investigated. Treatment of Ce[N(i-Pr2PO)2]3Cl (1) with AgMO4 (M = Re, Mn) afforded Ce[N(i-Pr2PO)2]3(ReO4) (2) or Ce2[N(i-Pr2PO)2]6(MnO4)2 (3). In the solid state, 3 is composed of a [Ce2{N(i-Pr2PO)2}6(MnO4)](+) moiety featuring a weak Ce-OMn interaction [Ce-OMn distance = 2.528(8) Å] and a noncoordinating MnO4(-) counteranion. While 3 is stable in the solid state and acetonitrile solution, it decomposes readily in other organic solvents, such as CH2Cl2. 3 can oxidize ethylbenzene to acetophenone at room temperature. Treatment of 1 with AgBF4, followed by reaction with [n-Bu4N]2[MoO4], afforded [Ce{N(i-Pr2PO)2}3]2(μ-MoO4) (4). Reaction of trans-Ce[N(i-Pr2PO)2]2(NO3)2 (5), which was prepared from (NH4)2Ce(NO3)6 and K[N(i-Pr2PO)2], with 2 equiv of [n-Bu4N][Cp*MoO3] yielded trans-Ce[N(i-Pr2PO)2]2(Cp*MoO3)2 (6). 4 can catalyze the oxidation of methyl phenyl sulfide with tert-butyl hydroperoxide with high selectivity. The crystal structures of complexes 3-6 have been determined.

77 FR 39491 - Combined Notice of Filings #2

Science.gov (United States)

2012-07-03

...-000. Applicants: Flat Ridge 2 Wind Energy LLC. Description: Notice of Self-Certification of Exempt Wholesale Generator Status of Flat Ridge 2 Wind Energy LLC. Filed Date: 6/26/12. Accession Number: 20120626... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Combined Notice of Filings 2 Take notice...

Hydrogenation of ethylene over PrCo5Hsub(2.4)

International Nuclear Information System (INIS)

Soga, Kazuo; Imamura, Hayao; Ikeda, Sakuji

1977-01-01

To elucidate the chemical reactivity of the hydrogen atom absorbed in the hydrogenated alloy PrCo 5 H sub(n), the hydrogenation of ethylene was carried out over PrCo 5 Hsub(2.4) in the absence (A) or presence (B) of hydrogen in gas phase. PrCo 5 Hsub(2.4) was prepared from PrCo 5 according to an ordinary procedure with repeated heating and cooling in hydrogen atmosphere. The hydrogenation of ethylene was conducted at about -70 0 C in a conventional gas circulation system in a pressure range of ethylene 5 -- 16 cmHg and hydrogen 0 -- 38.0 cmHg. The hydrogenation rate was followed by gas chromatography. In the case of (A), the total gas pressure in the gas phase remained constant during the reaction. The hydrogenation rate was independent of the partial pressure of ethylene and it increased in proportion to the concentration of the absorbed hydrogen atom. The rate of desorption of the absorbed hydrogen atom from PrCo 5 Hsub(2.4) also measured under a reduced pressure. The desorption rate was approximately the same as the hydrogenation rate under the similar conditions. From these results, it was concluded that the migration process of the absorbed hydrogen atom from the bulk of the alloy to its surface was rate-determining. In the case of (B), on the other hand, the hydrogenation rate was accelerated by the gaseous hydrogen; the rate increased almost linearly with increasing pressure of hydrogen. The hydrogenation of ethylene was also conducted over PrCo 5 under the similar conditions. (auth.)

76 FR 8725 - Notice of Baseline Filings

Science.gov (United States)

2011-02-15

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Notice of Baseline Filings Enstor Grama Ridge Storage and Docket No. PR10-97-002. Transportation, L.L.C.. EasTrans, LLC Docket No. PR10-30-001... revised baseline filing of their Statement of Operating Conditions for services provided under section 311...

PrP mRNA and protein expression in brain and PrP(c) in CSF in Creutzfeldt-Jakob disease MM1 and VV2.

Science.gov (United States)

Llorens, Franc; Ansoleaga, Belén; Garcia-Esparcia, Paula; Zafar, Saima; Grau-Rivera, Oriol; López-González, Irene; Blanco, Rosi; Carmona, Margarita; Yagüe, Jordi; Nos, Carlos; Del Río, José Antonio; Gelpí, Ellen; Zerr, Inga; Ferrer, Isidre

2013-01-01

Creutzfeldt-Jakob disease (CJD) is a heterogenic neurodegenerative disorder associated with abnormal post-translational processing of cellular prion protein (PrP(c)). CJD displays distinctive clinical and pathological features which correlate with the genotype at the codon 129 (methionine or valine: M or V respectively) in the prion protein gene and with size of the protease-resistant core of the abnormal prion protein PrP(sc) (type 1: 20/21 kDa and type 2: 19 kDa). MM1 and VV2 are the most common sporadic CJD (sCJD) subtypes. PrP mRNA expression levels in the frontal cortex and cerebellum are reduced in sCJD in a form subtype-dependent. Total PrP protein levels and PrP(sc) levels in the frontal cortex and cerebellum accumulate differentially in sCJD MM1 and sCJD VV2 with no relation between PrP(sc) deposition and spongiform degeneration and neuron loss, but with microgliosis, and IL6 and TNF-α response. In the CSF, reduced PrP(c), the only form present in this compartment, occurs in sCJD MM1 and VV2. PrP mRNA expression is also reduced in the frontal cortex in advanced stages of Alzheimer disease, Lewy body disease, progressive supranuclear palsy, and frontotemporal lobe degeneration, but PrP(c) levels in brain varies from one disease to another. Reduced PrP(c) levels in CSF correlate with PrP mRNA expression in brain, which in turn reflects severity of degeneration in sCJD.

Magnetic properties of Pr1-xGdxMn2Ge2 compounds

International Nuclear Information System (INIS)

Kilic, A.; Kervan, S.; Oezcan, S.; Gencer, A.

2004-01-01

The structure and magnetic properties of the Pr 1-x Gd x Mn 2 Ge 2 (0.0≤x≤1.0) compounds have been investigated by means of X-ray diffraction (XRD), differential scanning calorimetry (DSC) techniques and AC magnetic susceptibility measurements. All compounds crystallize in the ThCr 2 Si 2 -type structure with the space group I4/mmm. The lattice constants and the unit cell volume obey Vegard's law. Samples in this alloy system exhibit a crossover from ferromagnetic ordering for PrMn 2 Ge 2 to antiferromagnetic ordering for GdMn 2 Ge 2 as a function of Gd concentration x. At low temperatures, the rare earth sublattice also orders and reconfigures the ordering in the Mn sublattice. The results are summarized in the x-T magnetic phase diagram

Isothermal sections of the state diagram for the Pr-Ni-Ge system at 870 (0-0,5Pr) and 670 K (0,5-1Pr)

International Nuclear Information System (INIS)

Fedyna, M.F.; Pecharskij, V.K.; Bodak, O.I.

1987-01-01

Method of X-ray phase and microstructural analyses were used to study Pr-Ni-Ge ternary system at 870K (0-0.50 at.fractions of Pr) and 670K (0.50-1.00 at.fractions of Pr). 11 ternary compounds exist in the system: Pr 1-x (NiGe) 13 (x=0.24), PrNi 2 Ge 2 , Pr 2 Ni 3 Ge 5 , PrNiGe 3 , Pr 2 NiGe 6 , Pr 3 Ni 4 Ge 4 , PrNi (1-x) Ge 2 (x=0.33), PrNiGe, Pr(NiGe) 2-x (x=0.14), Pr 3 NiGe 2 , ∼Pr 5 NiGe 4 . Crystal structure was determined for seven ternary compounds

Electrocardiographic PR-interval duration and cardiovascular risk

DEFF Research Database (Denmark)

Rasmussen, Peter Vibe; Nielsen, Jonas Bille; Skov, Morten Wagner

2017-01-01

Background Because of ambiguous reports in the literature, we aimed to investigate the association between PR interval and the risk of all-cause and cardiovascular death, heart failure, and pacemaker implantation, allowing for a nonlinear relationship. MethodsWe included 293,111 individuals...... into 7 groups based on the population PR interval distribution. Cox models were used, with reference to a PR interval between 152 and 161 ms (40th to heart failure...... adjustment. A long PR interval conferred an increased risk of heart failure ( > 200 ms; HR, 1.31; 95% CI, 1.22-1.42; P 200 ms (HR, 3...

12 CFR 810.2 - Public notice of offering.

Science.gov (United States)

2010-01-01

... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Public notice of offering. 810.2 Section 810.2 Banks and Banking FEDERAL FINANCING BANK FEDERAL FINANCING BANK BILLS § 810.2 Public notice of offering. On the occasion of an offering of FFB bills, tenders therefor will be invited through public notices...

Synthesis and characterization of physical properties of Gd{sub 2}O{sub 2}S:Pr{sup 3+} semi-nanoflower phosphor

Energy Technology Data Exchange (ETDEWEB)

Bagheri, A.; Rezaee Ebrahim Saraee, Kh.; Shakur, H.R. [University of Isfahan, Department of Nuclear Engineering, Faculty of Advance Sciences and Technologies, Isfahan (Iran, Islamic Republic of); Zamani Zeinali, H. [Nuclear Science and Technology Research Institute, Agriculture, Medical and Industrial Research School, Karaj (Iran, Islamic Republic of)

2016-05-15

Pure gadolinium oxysulfide phosphor (Gd{sub 2}O{sub 2}S) and trivalent praseodymium-doped gadolinium oxysulfide phosphor (Gd{sub 2}O{sub 2}S:Pr{sup 3+}) scintillators with semi-nanoflower crystalline structures were successfully synthesized through a precipitation method and subsequent calcination treatment as a converter for X-ray imaging detectors. The characterization such as the crystal structures and nanostructure of Gd{sub 2}O{sub 2}S:Pr{sup 3+} scintillator measured by XRD and FeE-SEM experiment. The optical properties of Gd{sub 2}O{sub 2}S:Pr{sup 3+} scintillator were studied. Luminescence spectra of Gd{sub 2}O{sub 2}S:Pr{sup 3+} under 320 nm UV excitation show a green emission at near 511 nm corresponding to the {sup 3}P{sub 0}-{sup 3}H{sub 4} of Pr ions. After scintillation properties of synthesized Gd{sub 2}O{sub 2}S:Pr{sup 3+} scintillator investigated, Gd{sub 2}O{sub 2}S:Pr{sup 3+} scintillating film fabricated on a glass substrate by a sedimentation method. X-ray imaging of the fabricated scintillators confirmed that the Gd{sub 2}O{sub 2}S:Pr{sup 3+} scintillator could be used for radiography applications in which good spatial resolution is needed. (orig.)

First-principles study on cubic pyrochlore iridates Y2Ir2O7 and Pr2Ir2O7

International Nuclear Information System (INIS)

Ishii, Fumiyuki; Mizuta, Yo Pierre; Kato, Takehiro; Ozaki, Taisuke; Weng Hongming; Onoda, Shigeki

2015-01-01

Fully relativistic first-principles electronic structure calculations based on a noncollinear local spin density approximation (LSDA) are performed for pyrochlore iridates Y 2 Ir 2 O 7 and Pr 2 Ir 2 O 7 . The all-in, all-out antiferromagnetic (AF) order is stablized by the on-site Coulomb repulsion U > U c in the LSDA+U scheme, with U c ∼ 1.1 eV and 1.3 eV for Y 2 Ir 2 O 7 and Pr 2 Ir 2 O 7 , respectively. AF semimetals with and without Weyl points and then a topologically trivial AF insulator successively appear with further increasing U. For U = 1.3 eV, Y 2 Ir 2 O 7 is a topologically trivial narrow-gap AF insulator having an ordered local magnetic moment ∼0.5μ B /Ir, while Pr 2 Ir 2 O 7 is barely a paramagnetic semimetal with electron and hole concentrations of 0.016/Ir, in overall agreements with experiments. With decreasing oxygen position parameter x describing the trigonal compression of IrO 6 octahedra, Pr 2 Ir 2 O 7 is driven through a non-Fermi-liquid semimetal having only an isolated Fermi point of Γ 8 + , showing a quadratic band touching, to a Z 2 topological insulator. (author)

Fabrication and spectroscopic properties of nanocrystalline La{sub 2}Hf{sub 2}O{sub 7}:Pr

Energy Technology Data Exchange (ETDEWEB)

Trojan-Piegza, J., E-mail: jtp@eto.wchuwr.p [Faculty of Chemistry, Wroclaw University, 14 F. Joliot-Curie Street, 50383 Wroclaw (Poland); Zych, E.; Kosinska, M. [Faculty of Chemistry, Wroclaw University, 14 F. Joliot-Curie Street, 50383 Wroclaw (Poland)

2010-03-15

La{sub 2}Hf{sub 2}O{sub 7} nanopowders doped with different Pr concentrations (0.05-10 mol.%) were synthesized by the Pechini method. XRD measurements confirmed the single crystalline phase formed already at 800 {sup o}C and the structure was cubic pyrochlore. Luminescence excitation and emission as well as radioluminescence spectra were recorded for the materials. Both optical and X-ray excitation of La{sub 2}Hf{sub 2}O{sub 7}:Pr produced a red emission resulting from the 4f-4f transitions of Pr{sup 3+} ions. Luminescence of materials synthesized at low temperatures was characterized by broadband glass-type emissions, while heat treatment at 1400 {sup o}C led to spectra showing the typical for crystalline hosts narrow and intense 4f-4f transitions of Pr{sup 3+}.

76 FR 63628 - Preliminary Damage Assessment for Individual Assistance Operations Manual (9327.2-PR)

Science.gov (United States)

2011-10-13

...] Preliminary Damage Assessment for Individual Assistance Operations Manual (9327.2-PR) AGENCY: Federal... Individual Assistance Operations Manual (9327.2-PR). DATES: Comments must be received by November 14, 2011... of the draft Preliminary Damage Assessment for Individual Assistance Operations Manual (9327.2-PR) on...

Reactions of R(2)P-P(SiMe(3))Li with [(R'(3)P)(2)PtCl(2)]. A general and efficient entry to phosphanylphosphinidene complexes of platinum. Syntheses and structures of [(eta(2)-P=(i)Pr(2))Pt(p-Tol(3)P)(2)], [(eta(2)-P=(t)Bu(2))Pt(p-Tol(3)P)(2)], [{eta(2)-P=(N(i)Pr(2))(2)}Pt(p-Tol(3)P)(2)] and [{(Et(2)PhP)(2)Pt}(2)P(2)].

Science.gov (United States)

Domańska-Babul, Wioleta; Chojnacki, Jaroslaw; Matern, Eberhard; Pikies, Jerzy

2009-01-07

The reactions of lithium derivatives of diphosphanes R(2)P-P(SiMe(3))Li (R = (t)Bu, (i)Pr, Et(2)N and (i)Pr(2)N) with [(R'(3)P)(2)PtCl(2)] (R'(3)P = Et(3)P, Et(2)PhP, EtPh(2)P and p-Tol(3)P) proceed in a facile manner to afford side-on bonded phosphanylphosphinidene complexes of platinum [(eta(2)-P=R(2))Pt(PR'(3))(2)]. The related reactions of Ph(2)P-P(SiMe(3))Li with [(R'(3)P)(2)PtCl(2)] did not yield [(eta(2)-P=PPh(2))Pt(PR'(3))(2)] and resulted mainly in the formation of [{(R'(3)P)(2)Pt}(2)P(2)], Ph(2)P-PLi-PPh(2), (Me(3)Si)(2)PLi and (Me(3)Si)(3)P. Crystallographic data are reported for the compounds [(eta(2)-P=R(2))Pt(p-Tol(3)P)(2)] (R = (t)Bu, (i)Pr, ((i)Pr(2)N)(2)P) and for [{(Et(2)PhP)(2)Pt}(2)P(2)].

Crystal-field study of magnetization and specific heat properties of frustrated pyrochlore Pr2Zr2O7

International Nuclear Information System (INIS)

Alam, J.; Jana, Y.M.; Biswas, A. Ali

2016-01-01

The experimental results of temperature dependent dc magnetic susceptibility, field dependent isothermal magnetization, magnetic specific heat and entropy of the pyrochlore Pr 2 Zr 2 O 7 are simulated and analyzed using appropriate D 3d crystal-field (CF) and anisotropic molecular field tensors at Pr-sites in the self-consistent mean-field approach involving four magnetically non-equivalent rare-earth spins on the tetrahedral unit of the pyrochlore structure. CF level pattern and wave-functions of the ground 3 H 4 multiplet of the Pr 3+ ions are obtained considering intermediate coupling between different Russell-Saunders terms of the 4f 2 electronic configurations of Pr-ion and J-mixing effects. CF analysis shows that the CF ground-state of the Pr 3+ ion in Pr 2 Zr 2 O 7 is a well-isolated doublet, with significant admixtures of terms coming from |M J =±4〉 and |M J =±1〉, and the Pr-spins are effectively Ising-like along the local <111> axes. Magnetic specific heat in zero-field is simulated by considering a temperature dependence of the exchange splitting of the ground doublet. - Highlights: • Full CF diagonalization using intermediate coupling and J-mixing. • Pr-spins are Ising-like along local [111] axis. • Magnetic specific heat is due to temperature dependence exchange splitting of ground CF doublet.

Tips for the PR Chairman for Education Associations. PR Bookshelf No. 2.

Science.gov (United States)

National Education Association, Washington, DC.

This booklet is intended to aid leaders of local education associations in developing a continuing public relations (PR) program aimed at establishing and maintaining a favorable public image for teachers. Although it offers useful guidelines for developing a PR program, the booklet does not contain lists of specific things to do. Instead, it…

Valence determination as a function of doping in $PrBa_{2} Cu_{3} O_{7}$

CERN Document Server

Staub, U; Wasserman, S R; Conner, A G O; Kramer, M J; Patterson, B D; Shi, M; Knapp, M P

2000-01-01

We present results of X-ray absorption near edge spectra (XANES), neutron powder diffraction, and resonant X-ray diffraction on samples of PrBa/sub 2/Cu/sub 3/O/sub 7- delta / and Pr/sub 1-x/Ca/sub x/Ba /sub 2/Cu/sub 3/O/sub 7/. The data are obtained as a function of the doping levels of oxygen and Ca. There are significant changes in the Pr L/sub 3/ XANES spectra with changes in oxygen or Ca concentrations, indicating that the Pr electronic properties are affected by doping. The resonant X-ray scattering experiments show that the changes observed occur on Pr ions incorporated in the PrBa /sub 2/Cu/sub 3/O/sub 7- delta / structure, and are not the result of changes to a Pr-containing impurity phase. A quantitative model, based on literature precedent, is used to extract Pr valences from the data, although the XANES cannot distinguish between models involving charge transfer and those involving hybridization. The results are compared with data obtained from Pb/sub 2/Sr/sub 2/Pr/sub 1-x/Ca/sub x/Cu/sub 3/O/sub ...

Crystal structure of PrRh4.8B2

International Nuclear Information System (INIS)

Higashi, Iwami; Shishido, Toetsu; Takei, Humihiko; Kobayashi, Takaaki

1988-01-01

The crystal structure of a new rare earth ternary boride PrRh 4.8 B 2 was investigated, by single-crystal X-ray diffractometry. PrRh 4.8 B 2 crystallizes in the orthorhombic space group Immm with a = 9.697(4), b = 5.577(2), c = 25.64(3) A, Z=12. The intensity data were collected on a four-circle diffractometer with graphite-monochromatized Mo Kα radiation. The structure was solved by the Patterson method and refined with a full-matrix least-squares program to an R value (equal to Σvertical strokeΔFvertical stroke/Σvertical strokeF 0 vertical stroke) of 0.055 for 1176 reflections. (orig.)

Muon spin relaxation and nonmagnetic Kondo state in PrInAg2

International Nuclear Information System (INIS)

MacLaughlin, D. E.; Heffner, R. H.; Nieuwenhuys, G. J.; Canfield, P. C.; Amato, A.; Baines, C.; Schenck, A.; Luke, G. M.; Fudamoto, Y.; Uemura, Y. J.

2000-01-01

Muon spin relaxation experiments have been carried out in the Kondo compound PrInAg 2 . The zero-field muon relaxation rate is found to be independent of temperature between 0.1 and 10 K, which rules out a magnetic origin (spin freezing or a conventional Kondo effect) for the previously observed specific-heat anomaly at ∼0.5 K. At low temperatures the muon relaxation can be quantitatively understood in terms of the muon's interaction with nuclear magnetism, including hyperfine enhancement of the 141 Pr nuclear moment at low temperatures. This argues against a Pr 3+ ground-state electronic magnetic moment, and is strong evidence for the doublet Γ 3 crystalline-electric-field-split ground state required for a nonmagnetic route to heavy-electron behavior. The data imply the existence of an exchange interaction between neighboring Pr 3+ ions of the order of 0.2 K in temperature units, which should be taken into account in a complete theory of a nonmagnetic Kondo effect in PrInAg 2 . (c) 2000 The American Physical Society

77 FR 56837 - Enterprise Intrastate LLC; Notice of Filing

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2012-09-14

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. PR12-34-000] Enterprise Intrastate LLC; Notice of Filing Take notice that on September 6, 2012, Enterprise Intrastate LLC (Enterprise.... Enterprise Intrastate is revising its SOC to replace all references to ``Enterprise Intrastate L.P.'' with...

Redox behavior of a low-doped Pr-CeO_2(111) surface. A DFT+U study

International Nuclear Information System (INIS)

Milberg, Brian; Juan, Alfredo; Irigoyen, Beatriz

2017-01-01

Highlights: • Pr doping facilitates oxygen donation due to the easy formation of Pr"3"+/Pr"4"+ and Ce"3"+/Ce"4"+ redox couples. • Pr doping also favors the formation of superoxide (O_2"−) radicals on surface O-holes. • CO can be oxidized by superoxide radical forming a CO_2 molecule floating on the surface. • CO can also interact on the (O_2"−)/Pr"3"+ interphase and forms weakly adsorbed carbonate-type intermediates. - Abstract: In this work, we investigated the redox behavior (donation and replenishing of oxygen) of a low praseodymium (Pr)-doped CeO_2(111) surface. We considered a 3.7 at.% Pr doping and performed density functional calculations using the GGA formalism with the ‘U’ correction on Ce(4f) and Pr(4f) orbitals. Our results indicate that Pr doping promotes oxygen donation by lowering the energy necessary to form surface anionic vacancies. When the Ce_0_._9_6_3Pr_0_._0_3_7O_2(111) surface donates one oxygen, the two excess electrons locate on Pr and Ce cations and reduce them to Pr"3"+ and Ce"3"+ ones. Praseodymium doping also favors the activation of O_2 molecule on surface O-holes, leading to formation of a superoxide (O_2"−) radical as well as to reoxidation of the Ce"3"+ cation to Ce"4"+ one. Additionally, we used the CO molecular adsorption for testing the reactivity of those superoxide species. The calculations expose the ability of these radicals to oxidize CO forming a CO_2 molecule floating on the surface. However, when the superoxide is in the immediate vicinity of Pr dopant a carbonate-type species is formed. Our theoretical results may help to gain insight into redox properties and improved catalytic performance of low-doped Pr-CeO_2 solids.

Effects of partial Mn-substitution on magnetic and magnetocaloric properties in Pr{sub 0.7}Ca{sub 0.3}Mn{sub 0.95}X{sub 0.05}O{sub 3} (Cr, Ni, Co and Fe) manganites

Energy Technology Data Exchange (ETDEWEB)

Selmi, A. [Laboratoire de Physique des Matériaux, Faculté des Sciences de Sfax, Sfax University, B.P. 1171, 3000 Sfax (Tunisia); M’nassri, R., E-mail: rafik_mnassri@yahoo.fr [Higher Institute of Applied Sciences and Technology of Kasserine, Kairouan University, B.P. 471, 1200 Kasserine (Tunisia); Cheikhrouhou-Koubaa, W. [Laboratoire de Physique des Matériaux, Faculté des Sciences de Sfax, Sfax University, B.P. 1171, 3000 Sfax (Tunisia); Chniba Boudjada, N. [Institut NEEL, B.P. 166, 38042 Grenoble Cedex 9 (France); Cheikhrouhou, A. [Laboratoire de Physique des Matériaux, Faculté des Sciences de Sfax, Sfax University, B.P. 1171, 3000 Sfax (Tunisia)

2015-01-15

Highlights: • Pr{sub 0.7}Ca{sub 0.3}Mn{sub 0.95}X{sub 0.05}O{sub 3}(X = Cr, Ni, Co and Fe) ceramics were prepared by solid state method. • The manganite phases crystallize in an orthorhombic (Pnma) structure. • The samples exhibit a second order paramagnetic (PM)–ferromagnetic (FM) phase transition at the Curie temperature T{sub C}. • Maximum RCP equal to 405 J/kg observed for Pr{sub 0.7}Ca{sub 0.3}Mn{sub 0.95}Cr{sub 0.05}O{sub 3}. • Second order phase transition is confirmed by Arrott plots and universal curves of entropy change. • The experimental ΔS{sub M} are well predicted by the phenomenological universal curve. - Abstract: Structural, magnetic and magnetocaloric properties of Pr{sub 0.7}Ca{sub 0.3}Mn{sub 0.95}X{sub 0.05}O{sub 3}(X = Cr, Ni, Co and Fe) ceramics have been investigated by X-ray diffraction (XRD) and magnetic measurements. Powder samples have been elaborated using the solid state reaction method at high temperature. The Rietveld analysis of the powder X-ray diffraction shows that the samples crystallize in the orthorhombic structure with Pnma space group. Magnetic measurements show that all our materials exhibit a paramagnetic–ferromagnetic transition with decreasing temperature. The Arrott plots of ours materials reveal the occurrence of a second-order phase transition. The maximum values of magnetic entropy change |ΔS{sub M}{sup max}| are 2.92, 2.96, 3.1, and 2.38 J kg{sup −1} K{sup −1} and the relative cooling power (RCP) values are 405.8, 378.2, 352.2 and 337.4 J kg{sup −1} for a magnetic-field change from 0 to 5 T for Cr, Ni, Co and Fe respectively. The large RCP found in our substituted samples will be interesting for magnetic refrigeration over a wide temperature range ∼130 K around its paramagnetic to ferromagnetic transition temperature. With the scaling laws of ΔS{sub M}, the experimental ΔS{sub M} collapse onto a universal curve for several ceramics, where an average curve is obtained. With the

Exploring the crystallization landscape of cadmium bis(N-hydroxyethyl, N-isopropyldithiocarbamate), Cd[S{sub 2}CN(iPr)CH{sub 2}CH{sub 2}OH]{sub 2}

Energy Technology Data Exchange (ETDEWEB)

Tan, Yee Seng; Halim, Siti Nadiah Abdul [Malaya Univ., Kuala Lumpur (Malaysia). Dept. of Chemistry; Tiekink, Edward R.T. [Malaya Univ., Kuala Lumpur (Malaysia). Dept. of Chemistry; Sunway Univ., Bandar Sunway (Malaysia). Centre for Chemical Crystallography

2016-04-01

Crystallization of Cd[S{sub 2}CN(iPr)CH{sub 2}CH{sub 2}OH]{sub 2} from ethanol yields the coordination polymer [{Cd[S_2CN(iPr)CH_2CH_2OH]_2}.EtOH]{sub ∞} (1) within 3 h. When the solution is allowed to stand for another hour, the needles begin to dissolve and prisms emerge of the supramolecular isomer (SI), binuclear {Cd[S_2CN(iPr)CH_2CH_2OH]_2}{sub 2}.2EtOH (2). These have been fully characterized spectroscopically and by X-ray crystallography. Polymeric 1 has 2-fold symmetry and features dithiocarbamate ligands coordinating two octahedral Cd atoms in a μ{sub 2}κ{sup 2}-tridentate mode. Binuclear 2 is centrosymmetric with two ligands being μ{sub 2}κ{sup 2}-tridentate as for 1 but the other two being κ{sup 2}-chelating leading to square pyramidal geometries. The conversion of the kinetic crystallization product, 1, to thermodynamic 2 is irreversible but transformations mediated by recrystallization (ethanol and acetonitrile) to related literature SI species, namely coordination polymer [{Cd[S_2CN(iPr)CH_2CH_2OH]_2}{sub 3}.MeCN]{sub ∞} and binuclear {Cd[S_2CN(iPr)CH_2CH_2OH]_2}{sub 2}.2H{sub 2}O.2MeCN, are demonstrated, some of which are reversible. Three other crystallization outcomes are described whereby crystal structures were obtained for the 1:2 co-crystal {Cd[S_2CN(iPr)CH_2CH_2OH]_2}{sub 2}:2[3-(propan-2-yl)-1,3-oxazolidine-2-thione] (3), the salt co-crystal [iPrNH{sub 2}(CH{sub 2}CH{sub 2}OH)]{sub 4}[SO{sub 4}]{sub 2}{Cd[S_2CN(iPr)CH_2CH_2OH]_2}{sub 2} (4) and the salt [iPrNH{sub 2}(CH{sub 2}CH{sub 2}OH)]{Cd[S_2CN(iPr)CH_2CH_2OH]_3} (5). These arise as a result of decomposition/oxidation of the dithiocarbamate ligands. In each of 3 and 4 the binuclear {Cd[S_2CN(iPr)CH_2CH_2OH]_2}{sub 2} SI, as in 2, is observed strongly suggesting a thermodynamic preference for this form.

Risk of mortality of node-negative, ER/PR/HER2 breast cancer subtypes in T1, T2, and T3 tumors.

Science.gov (United States)

Parise, Carol A; Caggiano, Vincent

2017-10-01

The purpose of this study was to assess differences in breast cancer-specific mortality within tumors of the same size when breast cancer was defined using the three tumor markers estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2). We identified 104,499 cases of node-negative primary female invasive breast cancer from the California Cancer Registry. Tumor size was categorized as T1a, T1b, T1c, T2, and T3. Breast cancer was defined using ER, PR, and HER2. Kaplan-Meier Survival analysis was conducted and Cox Regression was used to compute the adjusted risk of mortality for the ER+/PR+/HER2+, ER-/PR-/HER2- (TNBC), and ER-/PR-/HER2+ (HER2-overexpressing) subtypes when compared with the ER+/PR+/HER2-. Separate models were computed for each tumor size. Unadjusted survival analysis showed that for all tumor sizes, the ER+/PR+ subtypes regardless of HER status have better breast cancer-specific survival than ER-/PR- subtypes. Subtype was not an important factor for risk of mortality for T1a tumors. The ER+/PR+/HER2+ subtype was only a risk for mortality in T1b tumors that were unadjusted for treatment. For all other tumor sizes, the ER+/PR+/HER2+ had the same mortality as the ER+/PR+/HER2- subtype regardless of adjustment for treatment. The HER2-overexpressing subtype had a higher risk of mortality than the ER+/PR+/HER2- subtype except for T1b tumors that were adjusted for treatment. For all tumor sizes, the TNBC had higher hazard ratios than all other subtypes. T1a tumors have the same risk of mortality regardless of ER/PR/HER2 subtype, and ER and PR negativity plays a stronger role in survival than HER2 positivity for tumors of all size.

77 FR 9224 - Combined Notice of Filings #2

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2012-02-16

... following exempt wholesale generator filings: Docket Numbers: EG12-31-000. Applicants: Quantum Choctaw Power, LLC. Description: Quantum Choctaw Power Notice of Self-certification of Exempt Wholesale Generator... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Combined Notice of Filings 2 Take notice...

Superstructure formation in PrNi_2Al_3 and ErPd_2Al_3

International Nuclear Information System (INIS)

Eustermann, Fabian; Hoffmann, Rolf-Dieter; Janka, Oliver; Oldenburg Univ.

2017-01-01

The intermetallic phase ErPd_2Al_3 was obtained by arc-melting of the elements and subsequent annealing for crystal growth. The sample was studied by X-ray diffraction on powders and single crystals. The structure of ErPd_2Al_3 was refined from X-ray diffraction data and revealed a superstructure of PrNi_2Al_3 - a CaCu_5 derivative (P6/m, a=1414.3(1), c=418.87(3) pm wR=0.0820, 1060 F"2 values, 48 variables). The same superstructure was subsequently found for PrNi_2Al_3 (P6/m, a=1407.87(4), c=406.19(2) pm, wR=0.0499, 904 F"2 values, 47 variables). In the crystal structure, the aluminium and transition metal atoms form a polyanionic network according to [T_2Al_3]"δ"-, while rare earth atoms fill cavities within the networks. They are coordinated by six transition metal and twelve aluminum atoms. In contrast to the PrNi_2Al_3 type structure reported so far, two crystallographic independent rare-earth sites are found of which one (1b) is shifted by 1/2 z, causing a distortion in the structure along with a recoloring of the T and Al atoms in the network.

Study of valence of cerium and praseodymium ions in Pr1-xCexO2 solid solutions

International Nuclear Information System (INIS)

Gartsman, K.G.; Kartenko, N.F.; Melekh, B.T.

1990-01-01

Effect of preparation conditions of Pr 1-x Ce x O 2 solid solutions on Ce and Pr ion valence within Pr 1-x Ce x O 2 system is studied. The data obtained enable to conclude that praseodymium may depending on annealing conditions change its state from Pr 3+ to Pr 4+ , while Ce 4+ is stable in Pr 1-x Ce x O 2 solid solutions

Energy Transfer between Er3+ and Pr3+ for 2.7 μm Fiber Laser Material

Directory of Open Access Journals (Sweden)

Xiangtan Li

2014-01-01

Full Text Available Energy transfer mechanisms between Er3+ and Pr3+ in Er3+/Pr3+ codoped germinate glass are investigated in detail. Under 980 nm LD pumping, 2.7 μm fluorescence intensity enhanced greatly. Meanwhile, 1.5 μm lifetime and fluorescence were suppressed deeply due to the efficient energy transfer from Er3+:4I13/2 to Pr3+:3F3,4, which depopulates the 4I13/2 level and promotes the 2.7 μm transition effectively. The obvious change in J-O parameters indicates that Pr3+ influences the local environment of Er3+ significantly. The increased spontaneous radiative probability in Er3+/Pr3+ glass is further evidence for enhanced 4I11/2 → 4I13/2 transition. The Er3+:4I11/2→Pr3+:1G4 process is harmful to the population accumulation on 4I11/2 level, which inhibits the 2.7 μm emission. The microscopic energy transfer coefficient of Er3+:4I13/2→Pr3+:3F3,4 is 42.25 × 10−40 cm6/s, which is 11.5 times larger than that of Er3+:4I11/2→Pr3+:1G4. Both processes prefer to be non-phonon assisted, which is the main reason why Pr3+ is so efficient in Er3+:2.7 μm emission.

75 FR 30014 - Consumers Energy Company; Notice of Baseline Filing

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2010-05-28

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. PR10-25-000] Consumers Energy Company; Notice of Baseline Filing May 21, 2010. Take notice that on May 17, 2010, Consumers Energy Company (Consumers) submitted a baseline filing of its Statement of Operating Conditions for the...

Race and perceived racism, education, and hypertension among Brazilian civil servants: the Pró-Saúde Study

Directory of Open Access Journals (Sweden)

Eduardo Faerstein

2014-01-01

Full Text Available INTRODUCTION: Brazil has the largest population of African descendants outside Africa. OBJECTIVE: Mindful of the imprint of slavery on their contemporary social position, we investigated the relationship of perceived racism to hypertension. METHODS: We analyzed data (1999 - 2001 from 3,056 civil servants (mean age 42 years; 56% females at university campuses in Rio participating in the longitudinal Pró-Saúde Study. RESULTS: Cases of prevalent hypertension had measured blood pressure equal to or greater than 140/90 mmHg or used antihypertensive medication. Self-administered questionnaires assessed participants' perceived history of lifetime discrimination (due to race, gender, socioeconomic position, and other attributes at work and school, neighborhood, public places, and in contact with the police. Participants used 41 terms as responses to an open-ended question on racial self-identification; for these analyses, 48% were classified as afrodescendants. Racial discrimination in at least one setting was reported by 14% of afrodescendants. Compared to whites, the age- and gender-adjusted prevalence of hypertension was higher for afrodescendants with history of self-perceived racism (prevalence ratio - PR = 2.1; 95%CI 1.5 - 3.0 than for those with no such history (PR = 1.5; 95%CI 1.2 - 1.8. Comparing the former to whites, the adjusted association with hypertension was stronger for those with elementary education (PR = 3.0; 95%CI 1.3 - 6.7 than for those with a college degree (PR = 1.7; 95%CI 1.0 - 3.1. CONCLUSION: Racism may increase the risk of hypertension of afrodescendants in Brazil, and socioeconomic disadvantage - also influenced by societal racism - may further potentiate this increased risk.

Race and perceived racism, education, and hypertension among Brazilian civil servants: the Pró-Saúde Study.

Science.gov (United States)

Faerstein, Eduardo; Chor, Dóra; Werneck, Guilherme Loureiro; Lopes, Claudia de Souza; Kaplan, George

2014-01-01

Brazil has the largest population of African descendants outside Africa. Mindful of the imprint of slavery on their contemporary social position, we investigated the relationship of perceived racism to hypertension. We analyzed data (1999 - 2001) from 3,056 civil servants (mean age 42 years; 56% females) at university campuses in Rio participating in the longitudinal Pró-Saúde Study. Cases of prevalent hypertension had measured blood pressure equal to or greater than 140/90 mmHg or used antihypertensive medication. Self-administered questionnaires assessed participants' perceived history of lifetime discrimination (due to race, gender, socioeconomic position, and other attributes) at work and school, neighborhood, public places, and in contact with the police. Participants used 41 terms as responses to an open-ended question on racial self-identification; for these analyses, 48% were classified as afrodescendants. Racial discrimination in at least one setting was reported by 14% of afrodescendants. Compared to whites, the age- and gender-adjusted prevalence of hypertension was higher for afrodescendants with history of self-perceived racism (prevalence ratio--PR = 2.1; 95%CI 1.5-3.0) than for those with no such history (PR = 1.5; 95%CI 1.2-1.8). Comparing the former to whites, the adjusted association with hypertension was stronger for those with elementary education (PR = 3.0; 95%CI 1.3-6.7) than for those with a college degree (PR = 1.7; 95%CI 1.0-3.1). Racism may increase the risk of hypertension of afrodescendants in Brazil, and socioeconomic disadvantage--also influenced by societal racism--may further potentiate this increased risk.

Hydrothermal synthesis and polymorphism of RbPr(MoO4)2

International Nuclear Information System (INIS)

Protasova, V.I.; Kharchenko, L.Yu.; Klevtsov, P.V.

1977-01-01

Hydrothermal method has been successfully used to obtain crystals of rubidium-rare-earth molibdates of RbLn(MoO 4 ) 2 composition (Ln is a rare earth element). In Rb 2 MoO 4 solutions at 575-600degC the RbPr(MoO 4 ) 2 crystals were obtained in a modification new for Rb-Ln-molibdates, i.e. isostructural to triclinic α-KEu(MoO 4 ) 2 , and in a structural modification of laminated rhombic KY(MoO 4 ) 2 type. Polymorphism of RbPr(MoO 4 ) 2 has been studied, four crystalline modifications found and their complex interchanges investigated

Magnetic excitations in modulated PrNi2Si2

International Nuclear Information System (INIS)

Blanco, J.A.; Nicklow, R.M.; Schmitt, D.

1994-01-01

The magnetic excitations in a single crystal of PrNi 2 Si 2 have been studied by inelastic neutron scattering. Dispersion curves have been followed through the centered tetragonal Brillouin zone. In the paramagnetic phase, at 39 K, the lowest energy magnetic branch exhibits an important dispersion ranging from 1.9 to 3.5 meV, the minimum energy occuring at the wave vector of the ordered phase; from the observed dispersion the inter-ionic isotropic bilinear exchange parameters are deduced. At 4.2 K, in the modulated phase, the same branch presents a dispersion slightly larger, but not significantly different

77 FR 43070 - Combined Notice of Filings #2

Science.gov (United States)

2012-07-23

...; ER10-2752-003. Applicants: Bangor Hydro Electric Company. Description: Notice of Changes in Status of Bangor Hydro Electric Company, et al. Filed Date: 7/16/12. Accession Number: 20120716-5085. Comments Due... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Combined Notice of Filings 2 Take notice...

Luminescence and light yield of (Gd2Y)(Ga3Al2)O12:Pr3+ single crystal scintillators

Science.gov (United States)

Lertloypanyachai, Prapon; Pathumrangsan, Nichakorn; Sreebunpeng, Krittiya; Pattanaboonmee, Nakarin; Chewpraditkul, Weerapong; Yoshikawa, Akira; Kamada, Kei; Nikl, Martin

2017-06-01

Praseodymium-doped (Gd2Y)(Ga3Al2)O12 (GYGAG: Pr) single crystals are grown by the micro-pulling down method with different Pr concentrations. The energy transfer process between Pr3+ and Gd3+ is investigated by photoluminescence excitation (PLE) and emission (PL) spectra measurements. Photoelectron yield measurements are carried out using photomultiplier. At 662 keV γ-rays, photoelectron yield of 2520 phe/MeV obtained for the GYGAG: Pr (0.01%) sample is larger than that of 1810 phe/MeV obtained for BGO crystal. Light yield degradation for the GYGAG: Pr scintillators is presumably due to the energy transfer from 5d state of Pr3+ to 4f state of Gd3+ together with the concentration quenching in the Gd3+-sublattice.

On the dimorphism of Pr{sub 6}Mo{sub 10}O{sub 39}

Energy Technology Data Exchange (ETDEWEB)

Rudolph, Daniel; Laufer, Sonja; Hartenbach, Ingo [Stuttgart Univ. (Germany). Inst. for Inorganic Chemistry

2017-07-01

Attempts to synthesize Pr{sub 4}Mo{sub 7}O{sub 27} using Pr, Pr{sub 6}O{sub 11} and MoO{sub 3} in a molar ratio of 8:6:77 led to a main product of scheelite-type Pr{sub 0.667}[MoO{sub 4}] and few single crystals of the triclinic A-type Pr{sub 6}Mo{sub 10}O{sub 39}. The latter crystallizes in space group P anti 1 (a=945.25(1), b=1058.49(2), c=1815.16(3) pm; α=104.149(1), β=95.220(1), γ=102.617(1) , Z=2). Its crystal structure comprises six crystallographically independent Pr{sup 3+} cations, eight tetrahedral [MoO{sub 4}]{sup 2-} units, and one [Mo{sub 2}O{sub 7}]{sup 2-} entity. The cations display coordination numbers of seven (1 x) and eight (5 x), while the [MoO{sub 4}]{sup 2-} tetrahedra are surrounded by five Pr{sup 3+} cations each. The [Mo{sub 2}O{sub 7}]{sup 2-} anions exhibit a coordination environment of seven Pr{sup 3+} cations. The attempt to synthesize PrF[MoO{sub 4}] using PrOF (from in situ thermal decomposition of PrF[CO{sub 3}]) as reagent did not lead to the desired product but to monoclinic B-type Pr{sub 6}Mo{sub 10}O{sub 39}. This slightly less dense modification compared to its triclinic analogue crystallizes in space group C2/c (a=1247.93(3), b=1989.68(6), c=1392.52 (4) pm, β=100.505(2) , Z=4) with three crystallographically independent Pr{sup 3+} cations, four [MoO{sub 4}]{sup 2-} tetrahedra, and again one [Mo{sub 2}O{sub 7}]{sup 2-} unit in the crystal structure. Thus, both Pr{sub 6}Mo{sub 10}O{sub 39} modifications are better described with the structured formula Pr{sub 6}[MoO{sub 4}]{sub 8}[Mo{sub 2}O{sub 7}]. The coordination numbers around the Pr{sup 3+} cations are seven (1 x) and eight (2 x) while all four [MoO{sub 4}]{sup 2-} anions are again surrounded by five Pr{sup 3+} cations each. Six of the latter represent the coordination environment around the [Mo{sub 2}O{sub 7}]{sup 2-} entities. Besides the thorough comparison of the crystal structures single crystal Raman spectra were recorded for both Pr{sub 6}Mo{sub 10}O{sub 39

Exchange-bias-like effect in Pr{sub 0.75}Tb{sub 0.25}Al{sub 2} and Pr{sub 0.7}Tb{sub 0.3}Al{sub 2} samples

Energy Technology Data Exchange (ETDEWEB)

Tedesco, J.C.G., E-mail: tedesco.jcg@gmail.com [Instituto de Física “Gleb Wataghin”, Universidade Estadual de Campinas—UNICAMP, 13083-859 Campinas, SP (Brazil); Pires, M.J.M. [Instituto de Ciência e Tecnologia—ICT, Universidade Federal dos Vales do Jequitinhonha e Mucuri—UFVJM, 39100-000 Diamantina, MG (Brazil); Carvalho, A. Magnus G. [Divisão de Metrologia de Materiais (DIMAT), INMETRO, 25250-020 Duque de Caxias, RJ (Brazil); Sousa, V.S.R. de [Instituto de Física “Armando Dias Tavares”, Universidade do Estado do Rio de Janeiro—UERJ, 20550-013 Rio de Janeiro, RJ (Brazil); Cardoso, L.P.; Coelho, A.A. [Instituto de Física “Gleb Wataghin”, Universidade Estadual de Campinas—UNICAMP, 13083-859 Campinas, SP (Brazil)

2013-08-15

The magnetic behavior of pseudobinary Pr{sub 0.7}Tb{sub 0.3}Al{sub 2} and Pr{sub 0.75}Tb{sub 0.25}Al{sub 2} compounds was studied, and a predominant ferrimagnetic ordering was observed. Noteworthy characteristics such as negative magnetization, compensation points and exchange-bias-like (EB-like) effect were found. This EB-like effect was observed at temperatures below the compensation points. The effect is somewhat different from the one already studied in similar systems combining light and heavy rare earths. The results indicate that the EB-like effect characteristics are related to the conduction electron magnetic polarization and an induced unidirectional anisotropy present in these compounds. - Highlights: ► Ferrimagnetic behavior is observed in Pr{sub 0.7}Tb{sub 0.3}Al{sub 2} and Pr{sub 0.75}Tb{sub 0.25}Al{sub 2} materials. ► Magnetic data indicate a strong unidirectional anisotropy in studied materials. ► Studied materials present the exchange-bias-like effect. ► Exchange-bias-like effect explained in analogy with the known mechanism of thin films.

78 FR 28837 - Acadian Gas Pipeline System; Notice of Petition

Science.gov (United States)

2013-05-16

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. PR11-129-001] Acadian Gas Pipeline System; Notice of Petition Take notice that on May 6, 2013, Acadian Gas Pipeline System (Acadian... concerns filed in the September 26, 2011 filing, as more fully detailed in the petition. Any person...

State diagram of Pr-Bi system

International Nuclear Information System (INIS)

Abulkhaev, V.L.; Ganiev, I.N.

1994-01-01

By means of thermal differential analysis, X-ray and microstructural analysis the state diagram of Pr-Bi system was studied. Following intermetallic compounds were defined in the system: Pr 2 Bi, Pr 5 Bi 3 , Pr 4 Bi 3 , Pr Bi, PrBi 2 , Pr 2 Bi, Pr 5 Bi 3 , Pr 4 Bi 3 and PrBi 2 . The data analysis on Ln-Bi diagram allowed to determine the regularity of change of properties of intermetallic compounds in the line of rare earth elements of cerium subgroup.

Quasi-homoepitaxial growth of a-axis oriented PrBa sub 2 Cu sub 3 O sub 7 sub - subdelta thick film on (100) YBa sub 2 Cu sub 3 O sub 7 sub - subdelta single crystal

CERN Document Server

Sato, M; Morishita, T

2003-01-01

The structural characterizations of the quasi-homoepitaxial growth of a-axis oriented PrBa sub 2 Cu sub 3 O sub 7 sub - subdelta thick film grown on (100) YBa sub 2 Cu sub 3 O sub 7 sub - subdelta single crystal were investigated in comparison with those of the film grown on (001) YBa sub 2 Cu sub 3 O sub 7 sub - subdelta single crystal. The a-axis oriented PrBa sub 2 Cu sub 3 O sub 7 sub - subdelta films, expected to be a barrier layer, were prepared using a dc-95 MHz hybrid plasma sputtering on (100) and (001) YBa sub 2 Cu sub 3 O sub 7 sub - subdelta single crystals that are superconducting ground planes. The atomic force microscopy image revealed that the surfaces of 700-nm-thick a-axis PrBa sub 2 Cu sub 3 O sub 7 sub - subdelta films on (100) YBa sub 2 Cu sub 3 O sub 7 sub - subdelta single crystals were smooth with a mean roughness of 2.8 nm. X-ray diffraction scans showed that a-axis PrBa sub 2 Cu sub 3 O sub 7 sub - subdelta films deposited on (100) YBa sub 2 Cu sub 3 O sub 7 sub - subdelta single cry...

76 FR 73618 - Enterprise Texas Pipeline LLC; Notice of Compliance Filing

Science.gov (United States)

2011-11-29

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket Nos. PR11-92-001] Enterprise Texas Pipeline LLC; Notice of Compliance Filing Take notice that on November 22, 2011, Enterprise Texas Pipeline LLC (Enterprise Texas) filed a revised Statement of Operating Conditions to comply with a...

77 FR 28373 - Liberty Energy (Midstates) Corp.; Notice of Baseline Filing

Science.gov (United States)

2012-05-14

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. PR12-24-000] Liberty Energy (Midstates) Corp.; Notice of Baseline Filing Take notice that on April 30, 2012, Liberty Energy (Midstates) Corp. submitted a baseline filing of their Statement of Operating Conditions for services provided...

PrP Knockout Cells Expressing Transmembrane PrP Resist Prion Infection.

Science.gov (United States)

Marshall, Karen E; Hughson, Andrew; Vascellari, Sarah; Priola, Suzette A; Sakudo, Akikazu; Onodera, Takashi; Baron, Gerald S

2017-01-15

Glycosylphosphatidylinositol (GPI) anchoring of the prion protein (PrP C ) influences PrP C misfolding into the disease-associated isoform, PrP res , as well as prion propagation and infectivity. GPI proteins are found in cholesterol- and sphingolipid-rich membrane regions called rafts. Exchanging the GPI anchor for a nonraft transmembrane sequence redirects PrP C away from rafts. Previous studies showed that nonraft transmembrane PrP C variants resist conversion to PrP res when transfected into scrapie-infected N2a neuroblastoma cells, likely due to segregation of transmembrane PrP C and GPI-anchored PrP res in distinct membrane environments. Thus, it remained unclear whether transmembrane PrP C might convert to PrP res if seeded by an exogenous source of PrP res not associated with host cell rafts and without the potential influence of endogenous expression of GPI-anchored PrP C To further explore these questions, constructs containing either a C-terminal wild-type GPI anchor signal sequence or a nonraft transmembrane sequence containing a flexible linker were expressed in a cell line derived from PrP knockout hippocampal neurons, NpL2. NpL2 cells have physiological similarities to primary neurons, representing a novel and advantageous model for studying transmissible spongiform encephalopathy (TSE) infection. Cells were infected with inocula from multiple prion strains and in different biochemical states (i.e., membrane bound as in brain microsomes from wild-type mice or purified GPI-anchorless amyloid fibrils). Only GPI-anchored PrP C supported persistent PrP res propagation. Our data provide strong evidence that in cell culture GPI anchor-directed membrane association of PrP C is required for persistent PrP res propagation, implicating raft microdomains as a location for conversion. Mechanisms of prion propagation, and what makes them transmissible, are poorly understood. Glycosylphosphatidylinositol (GPI) membrane anchoring of the prion protein (PrP C

Conhecimentos, atitudes e práticas acerca da detecção do câncer de próstata Conocimientos, actitudes y prácticas acerca de la detección del cáncer de próstata Knowledge, attitudes and practices regarding the detection of prostate cancer

Directory of Open Access Journals (Sweden)

Elenir Pereira de Paiva

2010-01-01

Full Text Available OBJETIVO: Analisar conhecimentos, atitudes e práticas em relação ao câncer de próstata de homens com idade entre 50 e 80 anos, adstritos à uma unidade do PSF no Município de Juiz de Fora - MG. MÉTODOS: Estudo seccional realizado por meio de inquérito domiciliar abrangendo amostra aleatória de 160 homens residentes em área adscrita desse programa. RESULTADOS: Da amostra, 69,4% eram casados, 88,8% tinham filhos, 86,3% informaram utilizar o PSF, 63,8% apresentaram conhecimento, 40,6% atitudes e 28,1% práticas adequadas. Os homens com conhecimento adequado tiveram prevalência 7,6 vezes (IC 95%=2,4-23,6 mais elevada de referir práticas adequadas. Aqueles com atitudes adequadas tiveram prevalência quase 2 vezes maior (RP=1,8; IC=1,1-3,0 de referir práticas adequadas. CONCLUSÃO: Este estudo corrobora a prevenção e a detecção precoce, como estratégias básicas para o controle do câncer de próstata, e têm como requisito essencial um conjunto de atividades educativas constantes, persistentes e dinâmicas para os homens.OBJETIVO: Analizar conocimientos, actitudes y prácticas en relación al cáncer de próstata de hombres con edad entre 50 y 80 años, inscritos en la una unidad del PSF en el Municipio de Juiz de Fora - MG. MÉTODOS: Estudio seccional realizado por medio de encuesta domiciliar abarcando una muestra aleatoria de 160 hombres residentes en área adscrita a ese programa. RESULTADOS: De la muestra, 69,4% eran casados, 88,8% tenían hijos, 86,3% informaron utilizar el PSF, 63,8% presentaron conocimiento, 40,6% actitudes y 28,1% prácticas adecuadas. Los hombres con conocimiento adecuado tuvieron incidencia 7,6 veces (IC 95%=2,4-23,6 más elevada de referir prácticas adecuadas. Aquellos con actitudes adecuadas tuvieron incidencia casi 2 veces mayor (RP=1,8; IC=1,1-3,0 de referir prácticas adecuadas. CONCLUSIÓN: Este estudio corrobora la prevención y la detección precoz, como estrategias básicas para el control del c

75 FR 53963 - Notice of Baseline Filings: The Peoples Gas Light and Coke Company, Minnesota Energy Resources...

Science.gov (United States)

2010-09-02

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. PR10-86-000, Docket No. PR10-87-000, Docket No. PR10-88- 000, Docket No. PR10-89-000, Docket No. PR10-90-000] Notice of Baseline Filings: The Peoples Gas Light and Coke Company, Minnesota Energy Resources Corporation, Louisville Gas...

75 FR 10026 - Proposed Collection; Comment Request for Forms W-2, W-2c, W-2AS, W-2GU, W-2VI, W-3, W-3c, W-3cPR...

Science.gov (United States)

2010-03-04

... W-2, W-2c, W-2AS, W-2GU, W-2VI, W-3, W-3c, W-3cPR, W-3PR, and W-3SS AGENCY: Internal Revenue Service....C. 3506(c)(2)(A)). Currently, the IRS is soliciting comments concerning Forms W-2, W-2c, W-2AS, W-2GU, W-2VI, W-3, W-3c, W- 3cPR, W-3PR, and W-3SS. DATES: Written comments should be received on or...

PR 2.0 müsteeriumid / Jaan Vare

Index Scriptorium Estoniae

Vare, Jaan, 1977-

2008-01-01

PR 2.0 ehk avalike suhete uus põlvkond kasutab rohkem uusi võimalusi, viies interneti ja sealsete kommuunide kaudu omavahel kokku turu eri segmendid ning ühendades tarbijaid tootjaga. Üheks uueks firma häälekandjaks veebis võib olla ka blogimine

High-Temperature Heat Capacity of Germanates Pr2Ge2O7 and Nd2Ge2O7 within 350-1000 K

Science.gov (United States)

Denisova, L. T.; Irtyugo, L. A.; Beletskii, V. V.; Belousova, N. V.; Denisov, V. M.

2018-03-01

Pr2Ge2O7 and Nd2Ge2O7 were obtained via solid-phase synthesis from Pr2O3 ( Nd2O3) and GeO2 with multistage firing in air within 1273-1473 K. A temperature effect on molar heat capacity of the oxide compounds was measured with a differential scanning calorimetry. Their thermodynamic properties were calculated from the C P = f( T) dependences.

Synthesis, characterization, and reactivity of nickel hydride complexes containing 2,6-C6H3(CH2PR2)2 (R = tBu, cHex, and iPr) pincer ligands.

Science.gov (United States)

Boro, Brian J; Duesler, Eileen N; Goldberg, Karen I; Kemp, Richard A

2009-06-15

The syntheses and full characterization of nickel hydrides containing the PCP "pincer"-type ligand, where PCP = 2,6-C(6)H(3)(CH(2)PR(2))(2) (R = tBu, cHex, and iPr), are reported. These Ni-H complexes are prepared by the conversion of ((R)PCP)NiCl precursors into the corresponding nickel hydrides by use of appropriate hydride donors. Surprisingly, although the ((R)PCP)NiCl precursors are quite similar chemically, the conversions to the hydrides were not straightforward and required different hydride reagents to provide analytically pure products. While NaBH(4) was effective in the preparation of pure ((tBu)PCP)NiH, Super-Hydride solution (LiEt(3)BH in THF) was required to prepare either ((cHex)PCP)NiH or ((iPr)PCP)NiH. Attempts to prepare a Ni-H from ((Ph)PCP)NiCl with a variety of hydride reagents yielded only the free ligand as an identifiable product. Two of the derivatives, tBu and cHex, have also been subjected to single crystal X-ray analysis. The solid-state structures each showed a classic, near-square planar arrangement for Ni in which the PCP ligand occupied three meridional ligand points with the Ni-H trans to the Ni-C bond. The resulting Ni-H bond lengths were 1.42(3) and 1.55(2) A for the tBu and cHex derivatives, respectively.

77 FR 31841 - Hope Gas, Inc.; Notice of Baseline Filing

Science.gov (United States)

2012-05-30

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. PR12-23-001] Hope Gas, Inc.; Notice of Baseline Filing Take notice that on May 16, 2012, Hope Gas, Inc. (Hope Gas) submitted a revised baseline filing of their Statement of Operating Conditions for services provided under Section 311 of the...

77 FR 26535 - Hope Gas, Inc.; Notice of Baseline Filing

Science.gov (United States)

2012-05-04

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. PR12-23-000] Hope Gas, Inc.; Notice of Baseline Filing Take notice that on April 26, 2012, Hope Gas, Inc. (Hope Gas) submitted a baseline filing of their Statement of Operating Conditions for services provided under Section 311 of the...

75 FR 33799 - EasTrans, LLC; Notice of Baseline Filing

Science.gov (United States)

2010-06-15

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. PR10-30-000] EasTrans, LLC; Notice of Baseline Filing June 8, 2010. Take notice that on June 4, 2010, EasTrans, LLC submitted a baseline filing of its Statement of Operating Conditions for services provided under section 311 of the...

75 FR 66748 - Notice of Baseline Filings

Science.gov (United States)

2010-10-29

...- 000] Notice of Baseline Filings October 22, 2010. ONEOK Gas Transportation, L.L.C Docket No. PR11-68... above submitted a revised baseline filing of their Statement of Operating Conditions for services...

PR-10 proteins as potential mediators of melatonin-cytokinin cross-talk in plants: crystallographic studies of LlPR-10.2B isoform from yellow lupine.

Science.gov (United States)

Sliwiak, Joanna; Sikorski, Michal; Jaskolski, Mariusz

2018-04-06

LlPR-10.2B, a Pathogenesis-related class 10 (PR-10) protein from yellow lupine (Lupinus luteus) was crystallized in complex with melatonin, an emerging important plant regulator and antioxidant. The structure reveals two molecules of melatonin bound in the internal cavity of the protein, plus a very well-defined electron density near the cavity entrance, corresponding to an unknown ligand molecule comprised of two flat rings, which is most likely a product of melatonin transformation. In a separate LlPR-10.2B co-crystallization experiment with an equimolar mixture of melatonin and trans-zeatin, which is a cytokinin phytohormone well recognized as a PR-10-binding partner, a quaternary 1 : 1 : 1 : 1 complex was formed, in which one of the melatonin-binding sites has been substituted with trans-zeatin, whereas the binding of melatonin at the second binding site and binding of the unknown ligand are undisturbed. This unusual complex, when compared with the previously described PR-10/trans-zeatin complexes and with the emerging structural information about melatonin binding by PR-10 proteins, provides intriguing insights into the role of PR-10 proteins in phytohormone regulation in plants, especially with the involvement of melatonin, and implicates the PR-10 proteins as low-affinity melatonin binders under the conditions of elevated melatonin concentration. Atomic coordinates and processed structure factors corresponding to the final models of the LlPR-10.2B/melatonin and LlPR-10.2B/melatonin + trans-zeatin complexes have been deposited with the Protein Data Bank (PDB) under the accession codes 5MXB and 5MXW. The corresponding raw X-ray diffraction images have been deposited in the RepOD Repository at the Interdisciplinary Centre for Mathematical and Computational Modelling (ICM) of the University of Warsaw, Poland, and are available for download with the following Digital Object Identifiers (DOI): https://doi.org/10.18150/repod.9923638 and https://doi.org/10

78 FR 6316 - Enterprise Texas Pipeline LLC; Notice of Compliance Filing

Science.gov (United States)

2013-01-30

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. PR13-23-000] Enterprise Texas Pipeline LLC; Notice of Compliance Filing Take notice that on January 17, 2013, Enterprise Texas Pipeline LLC filed a revised Statement of Operating Conditions to comply with a Commission order issued in...

75 FR 70732 - Enterprise Texas Pipeline LLC; Notice of Baseline Filing

Science.gov (United States)

2010-11-18

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. PR10-92-001] Enterprise Texas Pipeline LLC; Notice of Baseline Filing November 10, 2010. Take notice that on November 9, 2010, Enterprise Texas Pipeline LLC submitted a revised baseline filing of its Statement of Operating Conditions...

75 FR 27772 - Corning Natural Gas Corporation; Notice of Compliance Filing

Science.gov (United States)

2010-05-18

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. PR09-30-002] Corning Natural Gas Corporation; Notice of Compliance Filing May 11, 2010. Take notice that on May 3, 2010, Corning Natural Gas Corporation, (Corning) filed its Statement of section 311 Operating Conditions in compliance...

Redox behavior of a low-doped Pr-CeO{sub 2}(111) surface. A DFT+U study

Energy Technology Data Exchange (ETDEWEB)

Milberg, Brian [ITHES, UBA-CONICET, Departamento de Ingeniería Química, Pabellón de Industrias, Ciudad Universitaria, 1428 Buenos Aires (Argentina); Juan, Alfredo [Departamento de Física & IFISUR, UNS-CONICET, Avda. Alem 1253, 8000 Bahía Blanca (Argentina); Irigoyen, Beatriz, E-mail: beatriz@di.fcen.uba.ar [ITHES, UBA-CONICET, Departamento de Ingeniería Química, Pabellón de Industrias, Ciudad Universitaria, 1428 Buenos Aires (Argentina)

2017-04-15

Highlights: • Pr doping facilitates oxygen donation due to the easy formation of Pr{sup 3+}/Pr{sup 4+} and Ce{sup 3+}/Ce{sup 4+} redox couples. • Pr doping also favors the formation of superoxide (O{sub 2}{sup −}) radicals on surface O-holes. • CO can be oxidized by superoxide radical forming a CO{sub 2} molecule floating on the surface. • CO can also interact on the (O{sub 2}{sup −})/Pr{sup 3+} interphase and forms weakly adsorbed carbonate-type intermediates. - Abstract: In this work, we investigated the redox behavior (donation and replenishing of oxygen) of a low praseodymium (Pr)-doped CeO{sub 2}(111) surface. We considered a 3.7 at.% Pr doping and performed density functional calculations using the GGA formalism with the ‘U’ correction on Ce(4f) and Pr(4f) orbitals. Our results indicate that Pr doping promotes oxygen donation by lowering the energy necessary to form surface anionic vacancies. When the Ce{sub 0.963}Pr{sub 0.037}O{sub 2}(111) surface donates one oxygen, the two excess electrons locate on Pr and Ce cations and reduce them to Pr{sup 3+} and Ce{sup 3+} ones. Praseodymium doping also favors the activation of O{sub 2} molecule on surface O-holes, leading to formation of a superoxide (O{sub 2}{sup −}) radical as well as to reoxidation of the Ce{sup 3+} cation to Ce{sup 4+} one. Additionally, we used the CO molecular adsorption for testing the reactivity of those superoxide species. The calculations expose the ability of these radicals to oxidize CO forming a CO{sub 2} molecule floating on the surface. However, when the superoxide is in the immediate vicinity of Pr dopant a carbonate-type species is formed. Our theoretical results may help to gain insight into redox properties and improved catalytic performance of low-doped Pr-CeO{sub 2} solids.

Ferromagnetism in a hexagonal PrRh3 with 4f2 configuration

Science.gov (United States)

Park, G. B.; Yamane, Y.; Onimaru, T.; Umeo, K.; Takabatake, T.

2018-05-01

Electrical resistivity ρ , magnetization M and specific heat C are reported for polycrystalline samples of the hexagonal system PrRh3. The magnetic susceptibility M/B obeys the Curie-Weiss law with the effective magnetic moment μeff = 3.88 μB/Pr and the paramagnetic Curie temperature θp = +2.9 K, which indicates ferro-type magnetic interaction between the trivalent Pr ions. A cusp in C(T) at 3.0 K coincides with a bend in ρ (T). Applying magnetic fields, the peak broadens and shifts to higher temperatures. The field dependence indicates a ferro-type magnetic order. The magnetic entropy Sm is (1/3)Rln2 at TC = 3.0 K, suggesting that part of the Pr ions take part in the magnetic order. A broad tail of the magnetic specific heat Cm observed above TC may result from short-range correlations and/or fluctuations of the active magnetic dipole and quadrupoles in the ground state doublet.

75 FR 28602 - Corning Natural Gas Corporation; Notice of Compliance Filing

Science.gov (United States)

2010-05-21

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. PR09-30-003] Corning Natural Gas Corporation; Notice of Compliance Filing May 17, 2010. Take notice that on May 10, 2010, Corning Natural Gas Corporation, (Corning) filed a corrected rate sheet to replace the rate sheet filed with its...

75 FR 38802 - DCP Raptor Pipeline, LLC; Notice of Baseline Filing

Science.gov (United States)

2010-07-06

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. PR10-42-000] DCP Raptor Pipeline, LLC; Notice of Baseline Filing June 28, 2010. Take notice that on June 22, 2010, DCP Raptor Pipeline, LLC submitted a baseline filing of its Statement of Operating Conditions for services provided...

78 FR 7331 - SLR; Fajardo Offshore Grand Prix; Rada Fajardo; Fajardo, PR

Science.gov (United States)

2013-02-01

... DEPARTMENT OF HOMELAND SECURITY Coast Guard 33 CFR Part 100 [Docket Number USCG-2012-1098] RIN 1625-AA08 SLR; Fajardo Offshore Grand Prix; Rada Fajardo; Fajardo, PR AGENCY: Coast Guard, DHS. ACTION: Notice of Proposed Rulemaking. SUMMARY: The Coast Guard is establishing a special local regulation on the...

[Radioactive nuclides in the marine environment--distribution and behaviour of 95Zr, 95Nb originated from fallout].

Science.gov (United States)

Yamato, A; Miyagawa, N; Miyanaga, N

1984-07-01

To investigate behaviour of 95Zr, 95Nb in the marine environment, various samples have been collected and measured by means of Ge(Li) gamma-ray spectrometry and/or radiochemical analysis during a period from 1974 to 1982 at coastal area of Tokai-mura, Ibaraki prefecture. Concentration of the nuclides in seaweeds increased remarkably after atmospheric nuclear detonation by P.R. of China, and the activity ratio between the nuclides changed by time was not fit well by the transient decay equation. Concentration variation in sea water was smaller than that in sea weeds, and the minimum change in sea sediment. Increase of concentration in these environmental samples was observed in chronological order of sea water, sea weeds then sediment after detonations, suggesting that the uptake of the nuclides by these sea weeds from sea water is faster than that via root. Observed concentration factors on the nuclides by sea weeds were calculated from the observed concentrations in sea water and sea weeds. Maximum values on 95Zr and 95Nb were 2110, 2150, respectively for Ecklonia cava and Eisenia bicyclis.

26 CFR 1.854-2 - Notice to shareholders.

Science.gov (United States)

2010-04-01

... shall, upon notice by the Internal Revenue Service that the regulated investment company has failed to... 26 Internal Revenue 9 2010-04-01 2010-04-01 false Notice to shareholders. 1.854-2 Section 1.854-2 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED...

77 FR 21760 - Atmos Energy Colorado/Kansas Division; Notice of Baseline Filing

Science.gov (United States)

2012-04-11

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. PR12-19-000] Atmos Energy Colorado/Kansas Division; Notice of Baseline Filing Take notice that on March 30, 2012, Atmos Energy Colorado/Kansas Division (Atmos) submitted a baseline filing of their Statement of Operating Conditions for...

An investigation of the magnetic structure of PrO₂

DEFF Research Database (Denmark)

Gardiner, C.H.; Boothroyd, A.T.; Lister, S.J.S.

2002-01-01

We present a neutron-diffraction study of the crystal structure and magnetic ordering of PrO2. The magnetic moment of the Pr4+ ion is determined from separate single-crystal and powder measurements, and both values are found to agree with a previous powder study. Our powder data reveal a new aspect...

A cor da dor: iniquidades raciais na atenção pré-natal e ao parto no Brasil

Directory of Open Access Journals (Sweden)

Maria do Carmo Leal

Full Text Available Poucas pesquisas com foco nas influências da raça/cor no tocante à experiência de gestação e parto foram conduzidas no Brasil, sendo inédita a análise de abrangência nacional. Este estudo teve como objetivo avaliar as iniquidades na atenção pré-natal e parto de acordo com a raça/cor utilizando o método de pareamento baseado nos escores de propensão. Os dados são oriundos da pesquisa Nascer no Brasil: Pesquisa Nacional sobre Parto e Nascimento, um estudo de base populacional de abrangência nacional com entrevista e avaliação de prontuários de 23.894 mulheres em 2011/2012. Regressões logísticas simples foram utilizadas para estimar as razões de chance (OR e respectivos intervalos de 95% de confiança (IC95% da raça/cor associada aos desfechos analisados. Em comparação às brancas, puérperas de cor preta possuíram maior risco de terem um pré-natal inadequado (OR = 1,6; IC95%: 1,4-1,9, falta de vinculação à maternidade (OR = 1,2; IC95%: 1,1-1,4, ausência de acompanhante (OR = 1,7; IC95%: 1,4-2,0, peregrinação para o parto (OR = 1,3; IC95%: 1,2-1,5 e menos anestesia local para episiotomia (OR = 1,5 (IC95%: 1,1-2,1. Puérperas de cor parda também tiveram maior risco de terem um pré-natal inadequado (OR = 1,2; IC95%: 1,1-1,4 e ausência de acompanhante (OR = 1,4; IC95%: 1,3-1,6 quando comparadas às brancas. Foram identificadas disparidades raciais no processo de atenção à gestação e ao parto evidenciando um gradiente de pior para melhor cuidado entre mulheres pretas, pardas e brancas.

Significant association of RNF213 p.R4810K, a moyamoya susceptibility variant, with coronary artery disease.

Science.gov (United States)

Morimoto, Takaaki; Mineharu, Yohei; Ono, Koh; Nakatochi, Masahiro; Ichihara, Sahoko; Kabata, Risako; Takagi, Yasushi; Cao, Yang; Zhao, Lanying; Kobayashi, Hatasu; Harada, Kouji H; Takenaka, Katsunobu; Funaki, Takeshi; Yokota, Mitsuhiro; Matsubara, Tatsuaki; Yamamoto, Ken; Izawa, Hideo; Kimura, Takeshi; Miyamoto, Susumu; Koizumi, Akio

2017-01-01

The genetic architecture of coronary artery disease has not been fully elucidated, especially in Asian countries. Moyamoya disease is a progressive cerebrovascular disease that is reported to be complicated by coronary artery disease. Because most Japanese patients with moyamoya disease carry the p.R4810K variant of the ring finger 213 gene (RNF213), this may also be a risk factor for coronary artery disease; however, this possibility has never been tested. We genotyped the RNF213 p.R4810K variant in 956 coronary artery disease patients and 716 controls and tested the association between p.R4810K and coronary artery disease. We also validated the association in an independent population of 311 coronary artery disease patients and 494 controls. In the replication study, the p.R4810K genotypes were imputed from genome-wide genotyping data based on the 1000 Genomes Project. We used multivariate logistic regression analyses to adjust for well-known risk factors such as dyslipidemia and smoking habits. In the primary study population, the frequency of the minor variant allele was significantly higher in patients with coronary artery disease than in controls (2.04% vs. 0.98%), with an odds ratio of 2.11 (p = 0.017). Under a dominant model, after adjustment for risk factors, the association remained significant, with an odds ratio of 2.90 (95% confidence interval: 1.37-6.61; p = 0.005). In the replication study, the association was significant after adjustment for age and sex (odds ratio = 4.99; 95% confidence interval: 1.16-21.53; p = 0.031), although it did not reach statistical significance when further adjusted for risk factors (odds ratio = 3.82; 95% confidence interval: 0.87-16.77; p = 0.076). The RNF213 p.R4810K variant appears to be significantly associated with coronary artery disease in the Japanese population.

40 CFR 141.203 - Tier 2 Public Notice-Form, manner, and frequency of notice.

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2010-07-01

... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Tier 2 Public Notice-Form, manner, and frequency of notice. 141.203 Section 141.203 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY...., house renters, apartment dwellers, university students, nursing home patients, prison inmates, etc...

PR-PR: cross-platform laboratory automation system.

Science.gov (United States)

Linshiz, Gregory; Stawski, Nina; Goyal, Garima; Bi, Changhao; Poust, Sean; Sharma, Monica; Mutalik, Vivek; Keasling, Jay D; Hillson, Nathan J

2014-08-15

To enable protocol standardization, sharing, and efficient implementation across laboratory automation platforms, we have further developed the PR-PR open-source high-level biology-friendly robot programming language as a cross-platform laboratory automation system. Beyond liquid-handling robotics, PR-PR now supports microfluidic and microscopy platforms, as well as protocol translation into human languages, such as English. While the same set of basic PR-PR commands and features are available for each supported platform, the underlying optimization and translation modules vary from platform to platform. Here, we describe these further developments to PR-PR, and demonstrate the experimental implementation and validation of PR-PR protocols for combinatorial modified Golden Gate DNA assembly across liquid-handling robotic, microfluidic, and manual platforms. To further test PR-PR cross-platform performance, we then implement and assess PR-PR protocols for Kunkel DNA mutagenesis and hierarchical Gibson DNA assembly for microfluidic and manual platforms.

The Pr and Ca substitution in GdBa2Cu3O7-8

International Nuclear Information System (INIS)

Shakeri, H.; Akhavan, M.

2002-01-01

The granular Gd 1 -x-zPr x Ca z Ba 2 Cu 3 O 7 -8 (Gd Pr Ca-123) high-temperature cuprate samples with 0.0≤x≤0.3 and 0.0≤z≤0.35 are prepared by standard solid state reaction and characterized by XRD and SEM techniques. The BaCuO 2 and impurity phases are less than 1% in the samples having high levels of Pr and Ca concentrations. The electrical resistivity measurements show a nonlinear reduction in T c (x,z=etc) versus x. Moreover, the T c (z) curve with x=0 is nonlinear and a plateau appears at z≅0.05-0.015. For Pr-Ca-doped samples with a constant concentration of Pr, T c increases with the increase of Ca up to an optimum value of Ca doping and then in decreases. Based on these observations, we suggest that hole filling and hole localization the main effects of Pr ion substitution. The magnetic measurements indicate that the value of H C 1 is in the order of 10 m T. The magnetoresistance measurements have been measured and analyzed. The superconducting transition region is broadened by the application of magnetic field. The experimental data near the on sen of superconductivity are fitted with the Ambegakor and Halperin (A H) phase-slip model. We observe that the A H parameter, γ(H), depends not only on the temperature and the magnetic field, but also on the Pr and Ca ions concentrations. It is observed that the critical current density increases with Ca substitution and decreases with pr substitution in Gd-123 system. We suggest that the pr ion substitution probably enhances the weak link, but the Ca ion acts as flux pinning center in the Gd Pr Ca-123 system

76 FR 46283 - Peoples Natural Gas Company LLC; Notice of Baseline Filing

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2011-08-02

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. PR11-3-001] Peoples Natural Gas Company LLC; Notice of Baseline Filing Take notice that on July 20, 2011, Peoples Natural Gas... provided under Section 311 of the Natural Gas Policy Act of 1978 (NGPA). Any person desiring to participate...

The Pr 2O 3/Si(0 0 1) interface studied by synchrotron radiation photo-electron spectroscopy

Science.gov (United States)

Schmeißer, D.; Müssig, H.-J.

2003-10-01

Pr 2O 3 is currently under consideration as a potential replacement for SiO 2 as the gate-dielectric material for sub-0.1 μm complementary metal-oxide-semiconductor (CMOS) technology. We studied the Pr 2O 3/Si(0 0 1) interface by a non-destructive depth profiling using synchrotron radiation photoelectron spectroscopy. Our data suggests that there is no silicide formation at the interface. Based on reported results, a chemical reactive interface exists, consisting of a mixed Si-Pr oxide such as (Pr 2O 3) x(SiO 2) 1- x, i.e. as a silicate phase with variable silicon content. This pseudo-binary alloy at the interface offers large flexibility toward successful integration of Pr 2O 3 into future CMOS technologies.

77 FR 23244 - Atmos Energy Colorado/Kansas Division; Notice of Revised Baseline Filing

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2012-04-18

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. PR12-22-000] Atmos Energy Colorado/Kansas Division; Notice of Revised Baseline Filing Take notice that on April 10, 2012, Atmos Energy Colorado/Kansas Division (Atmos) filed a revised baseline filing of their Statement of Operating...

76 FR 2361 - Atmos Energy-Kentucky/Mid-States Division; Notice of Baseline Filing

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2011-01-13

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. PR11-77-000] Atmos Energy--Kentucky/Mid-States Division; Notice of Baseline Filing January 5, 2011. Take notice that on December 30, 2010, Atmos Energy--Kentucky/Mid- States Division submitted a revised baseline filing of their...

Prolonged PR interval predicts clinical recurrence of atrial fibrillation after catheter ablation.

Science.gov (United States)

Park, Junbeom; Kim, Tae-Hoon; Lee, Jihei Sara; Park, Jin Kyu; Uhm, Jae Sun; Joung, Boyoung; Lee, Moon Hyoung; Pak, Hui-Nam

2014-10-07

A prolonged PR interval is known to be a poor prognostic factor in cardiovascular disease. The aim of this study was to investigate the association between PR interval and clinical outcome in patients undergoing radiofrequency catheter ablation (RFCA) of atrial fibrillation (AF). We prospectively included 576 patients with AF (75.5% male, 57.8±11.6 years old, 68.8% paroxysmal AF) who underwent RFCA. We analyzed preprocedural sinus rhythm ECGs obtained in the absence of antiarrhythmic drug, and all enrolled patients were categorized into 4 groups based on the quartile values of the PR interval (166, 182, and 202 ms), and were analyzed according to the left atrium (LA) volume (CT; Computed tomography), LA voltage (NavX), and clinical outcome of AF ablation. Based on quartile value of PR interval, the highest quartile of PR interval (Q4; PR ≥202 ms) was oldest (PPR interval was a significant predictor of AF recurrence after RFCA of AF (HR=1.969, 95% CI 1.343 to 2.886, P=0.001). The PR interval was closely associated with advanced LA remodeling due to AF, and had a noninvasive significant predictive value of clinical recurrence of AF after RFCA. © 2014 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

Evaluation of Gd{sub 2}O{sub 2}S:Pr granular phosphor properties for X-ray mammography imaging

Energy Technology Data Exchange (ETDEWEB)

David, S.; Michail, C. [Department of Biomedical Engineering, Technological Educational Institute (TEI) of Athens, Ag. Spyridonos Street, 122 10 Egaleo (Greece); Seferis, I. [Department of Biomedical Engineering, Technological Educational Institute (TEI) of Athens, Ag. Spyridonos Street, 122 10 Egaleo (Greece); Faculty of Chemistry, Wroclaw University, 14F Joliot-Curie Street, 50-383 Wroclaw (Poland); Valais, I.; Fountos, G.; Liaparinos, P.; Kandarakis, I. [Department of Biomedical Engineering, Technological Educational Institute (TEI) of Athens, Ag. Spyridonos Street, 122 10 Egaleo (Greece); Kalyvas, N., E-mail: nkalyvas@teiath.gr [Department of Biomedical Engineering, Technological Educational Institute (TEI) of Athens, Ag. Spyridonos Street, 122 10 Egaleo (Greece)

2016-01-15

Phosphor materials are widely used in X-ray medical imaging detector applications, coupled with suitable photoreceptors. Upon the most demanding imaging modality is X-ray mammography, since the best defense against breast cancer is its early detection. A material suitable as a mammographic detector should efficiently absorb X-ray photons and transform them to optical photons, so as to minimize breast dose. The aim of the present study was to investigate the X-ray absorption efficiency and the absolute efficiency (AE), defined as the output optical photon power divided by the incident exposure, of Gd{sub 2}O{sub 2}S:Pr powder scintillator. For the purposes of this study, three scintillating screens with coating thicknesses, 34.1, 46.0 and 81.5 mg/cm{sup 2} respectively, were prepared in our laboratory from Gd{sub 2}O{sub 2}S:Pr powder (Phosphor Technology, Ltd.) by sedimentation on silica substrates. The quantum detection efficiency (QDE), the energy absorption efficiency (EAE), the spectral matching factor and the absolute efficiency (AE) were evaluated for X-ray mammographic conditions. Furthermore theoretical models were utilized to investigate the optical photon transmission properties through the phosphor mass. Gd{sub 2}O{sub 2}S:Pr presented high X-ray absorption properties and good spectral compatibility with several photoreceptors. It may be utilized for X-ray mammographic imaging if it is put in conjunction with a sensitive photoreceptor, so as to enhance Gd{sub 2}O{sub 2}S:Pr light emission properties. - Highlights: • Gd{sub 2}O{sub 2}S:Pr phosphor evaluated for mammography detectors. • The X-ray absorption efficiency was found high. • Spectral matching compatibility found for several photoreceptors. • X-ray absolute efficiency measured smaller than other phosphors. • Optical diffusion length and the light transmission per layer was theoretically calculated.

77 FR 71412 - Combined Notice of Filings #2

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2012-11-30

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Combined Notice of Filings 2 Take notice that the Commission has received the following Natural Gas Pipeline Rate and Refund Report filings: Filings Instituting Proceedings Docket Numbers: RP13-301-000. Applicants: Venice Gathering System, LLC...

77 FR 23710 - Combined Notice of Filings #2

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2012-04-20

..., LLC, MXenergy Electric Inc., Wildcat Wind, LLC, Tuana Springs Energy, LLC, Constellation Power Source... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Combined Notice of Filings 2 Take notice that the Commission received the following exempt wholesale generator filings: Docket Numbers: EG12-54...

77 FR 31609 - Combined Notice of Filings #2

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2012-05-29

...-001. Applicants: High Majestic Wind Energy Center, LLC. Description: High Majestic Wind Energy Center... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Combined Notice of Filings 2 Take notice that the Commission received the following exempt wholesale generator filings: Docket Numbers: EG12-68...

78 FR 36767 - Combined Notice of Filings #2

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2013-06-19

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Combined Notice of Filings 2 Take notice that the Commission received the following electric corporate filings: Docket Numbers: EC13-115-000. Applicants: Puget Sound Energy, Inc., Electron Hydro, LLC. Description: Application for Authorization for...

77 FR 63307 - Combined Notice of Filings #2

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2012-10-16

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Combined Notice of Filings 2 Take notice that the Commission received the following electric corporate filings: Docket Numbers: EC13-7-000. Applicants: Bangor Hydro Electric Company. Description: Application Under FPA Section 203 of Bangor Hydro...

78 FR 67136 - Combined Notice of Filings #2

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2013-11-08

...: Bangor Hydro Electric Company. Description: Bangor Hydro Electric Company submits Filing to Effect... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Combined Notice of Filings 2 Take notice that the Commission received the following electric corporate filings: Docket Numbers: EC14-15-000...

77 FR 27221 - Combined Notice of Filings #2

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2012-05-09

.... ET 5/23/12. Docket Numbers: ER12-1698-000. Applicants: New Mexico Renewable Energy Transmission..., LLC, New Mexico Renewable Energy Transmission Authority. Description: Request for Limited Waiver of... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Combined Notice of Filings 2 Take notice...

Effects of Pr-deficiency on thermal expansion and electrochemical properties in Pr_1_−_xBaCo_2O_5_+_δ cathodes for IT-SOFCs

International Nuclear Information System (INIS)

Zhang, Leilei; Yao, Guibin; Song, Zhaoyuan; Niu, Bingbing; Long, Wen; Zhang, Lei; Shen, Yu; He, Tianmin

2016-01-01

Highlights: • Single phase oxides P_1_−_xBCO with x = 0.00–0.10 were successfully prepared. • TECs and electrical conductivities of P_1_−_xBCO cathodes decrease with Pr-deficiency. • Among P_1_−_xBCO cathodes, P_0_._9_2BCO exhibits the lowest polarization resistance. • Electron charge transfer plays a dominant role in cathode oxygen reduction. • P_m_a_x of 987 mW cm"−"2 at 800 °C for P_0_._9_2BCO cathode is obtained on SDC electrolyte. - Abstract: Pr-deficient Pr_1_−_xBaCo_2O_5_+_δ (P_1_−_xBCO) oxides are evaluated as cathode materials for intermediate temperature solid oxide fuel cells (IT-SOFCs). Effects of Pr-deficiency on electrical conductivity, thermal expansion and electrochemical properties are investigated. Both the conductivity and thermal expansion coefficient (TEC) decrease with increasing Pr-deficiency. All of the conductivity, thermal expansion and TGA measurements demonstrate the existence of high temperature order-disorder transition. The oxygen reduction mechanism for P_1_−_xBCO cathodes are characterized by electrochemical impedance spectroscopy. Over the temperature range of 600−800 °C, the cathode polarization resistance is mainly contributed from electronic charge transfer over the cathode surface. Proper Pr-deficiency reduces cathode polarization resistance (R_p), and the lowest R_p (0.081 Ω cm"2 at 700 °C) is obtained for the P_0_._9_2BCO cathode. In addition, the effects of order-disorder transition on the properties of P_1_−_xBCO cathodes have also been discussed. Maximum power densities of a single-cell with P_0_._9_2BCO cathode on 300-μm thick Sm_0_._2Ce_0_._8O_1_._9 (SDC) electrolyte achieve 446–987 mW cm"−"2 at 650–800 °C. These results suggest that, among various P_1_−_xBCO oxides, P_0_._9_2BCO is the most promising candidate cathode material for IT-SOFCs.

75 FR 74706 - Notice of Baseline Filings

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2010-12-01

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Notice of Baseline Filings November 24, 2010. Centana Intrastate Pipeline, LLC. Docket No. PR10-84-001. Centana Intrastate Pipeline, LLC... applicants listed above submitted a revised baseline filing of their Statement of Operating Conditions for...

75 FR 68607 - CenterPoint Energy-Illinois Gas Transmission Company; Notice of Baseline Filing

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2010-11-08

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. PR10-80-001] CenterPoint Energy--Illinois Gas Transmission Company; Notice of Baseline Filing November 1, 2010. Take notice that on October 28, 2010, CenterPoint Energy--Illinois Gas Transmission Company submitted a revised...

78 FR 20314 - Jefferson Island Storage & Hub, L.L.C.; Notice of Filing

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2013-04-04

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. PR13-44-000] Jefferson Island Storage & Hub, L.L.C.; Notice of Filing Take notice that on March 28, 2013, Jefferson Island Storage & Hub, L.L.C. filed to revise its Statement of Operating Conditions to among others, update...

76 FR 20657 - Hattiesburg Industrial Gas Sales, L.L.C.; Notice of Filing

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2011-04-13

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. PR10-102-001] Hattiesburg Industrial Gas Sales, L.L.C.; Notice of Filing Take notice that on April 1, 2011, Hattiesburg Industrial Gas Sales, L.L.C. (Hattiesburg) filed a revised Statement of Operating Conditions to comply with a...

78 FR 21929 - Hattiesburg Industrial Gas Sales, L.L.C.; Notice of Filing

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2013-04-12

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. PR13-46-000] Hattiesburg Industrial Gas Sales, L.L.C.; Notice of Filing Take notice that on April 1, 2013, Hattiesburg Industrial Gas Sales, L.L.C. (Hattiesburg) filed to cancel its Statement of Operating Conditions including its Tariff...

78 FR 11635 - Combined Notice of Filings #2

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2013-02-19

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Combined Notice of Filings 2 Take notice.... Applicants: Wildcat Wind Farm I, LLC. Description: Wildcat Wind Farm I, LLC withdraws request for... electric rate filings: Docket Numbers: ER13-916-000. Applicants: Public Service Company of New Mexico...

78 FR 40472 - Combined Notice of Filings #2

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2013-07-05

.... Applicants: Bangor Hydro Electric Company, Maine Public Service Company. Description: Errata to March 19, 2013 Section 203 Application of Bangor Hydro Electric Company, et. al. and Request for Shortened Answer... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Combined Notice of Filings 2 Take notice...

Transport properties of RCo_2B_2C with R = Dy, Ho, and Pr single

Science.gov (United States)

Duran, Alejandro; Escudero, Roberto

2002-03-01

Single crystals of (Dy, Ho, Pr)Co_2B_2C have been grown by a cold copper crucible method. Metallurgical and structural studies indicate that this borocarbide family melts incongruently and crystallizes as a derivative structure of the ThCr_2Si_2. The family accepts rare earth atoms depending on the type of transition metals used to form the compound. For instance with Ni atoms, all lanthanides ranging from the large lanthanum to lutetium ions are reported to form RNi_2B_2C single crystals, so far no single crystals have been obtained when changing Ni by Cobalt. A comparison of the structural parameters of the RCo_2B_2C with the RNiHo, Pr) compounds indicate that the atomic distance between transition metal atoms contracts with the insertion of the Co ion, resulting in an increasing of the c parameter and decreasing volume. Several recent reports published in the current literature related on the physical properties of RCo_2B_2C (R = rare earth metals and Y) have been only performed on polycrystalline samples, they commonly contain small amounts of second phases. High quality single crystals are necessaries in order to better understand the physical properties, such as anisotropy in the transport and in the magnetic properties. In this report we show magnetic susceptibility and resistivity measurements performed in single crystals in the ab-plane and c direction for 2 - 320 K temperature range for the three single crystals of (Dy, Ho, Pr)Co_2B_2C.

Influence of the valence states of atoms on conducting properties of PrBa2Cu3O6+x

International Nuclear Information System (INIS)

Romanenko, A.I.; Zakharchuk, N.F.; Naumov, N.G.; Fedorov, V.E.; Paek, U.H.

1997-01-01

Pr 3+ valent state only was discovered in PrBa 2 Cu 3 O 6+x within the oxygen content range 0.4 ≤ x ≤ 0.6. Out of this range, Pr 4+ state appears also. All the samples obtained showed insulating behavior of resistivity r(T). In PrBa 2 Cu 3 O 6+x (0.4 ≤ x ≤ 0.6), the resistivity is Mott variable-range hopping conduction type and is connected with oxygen disorder only. Out of this range, the localization is much stronger; this increase is due to Pr 4+ /Pr 3+ position disorder. Also, the localization decreases after annealing at room temperature is the result of ordering. Thus, the absence of metallic (and therefore superconducting) state in PrBa 2 Cu 3 O 6+x is due to the presence of both Pr 4+ and Pr 4+ /Pr 3+ disorder

Optical investigation of the valency of Pr in Y1-xPrxBa2Cu3O7-δ

International Nuclear Information System (INIS)

Kircher, J.; Cardona, M.; Gopalan, S.; Habermeier, H.; Fuchs, D.

1991-01-01

We have investigated the dependence of the visible-ultraviolet dielectric function of Y 1-x Pr x Ba 2 Cu 3 O 7 on the Pr content x using rotating analyzer ellipsometry. Based on recently published band-structure calculations, we believe that the valency of Pr can be deduced from the optical properties in this spectral region. Interband transitions should shift to higher energies for Pr 4+ and to lower energies for Pr 3+ when compared to the optical spectra of YBa 2 Cu 3 O 7 . In the case of tetravalent Pr ions, transitions into unoccupied Pr 5d levels should be observable. Since the experimental energies for interband transitions shift down with increasing x and no additional structure can be seen, we conclude that Pr is trivalent in Y 1-x Pr x Ba 2 Cu 3 O 7

Quantitative measurements of tumoral p95HER2 protein expression in metastatic breast cancer patients treated with trastuzumab: independent validation of the p95HER2 clinical cutoff.

Science.gov (United States)

Duchnowska, Renata; Sperinde, Jeff; Chenna, Ahmed; Haddad, Mojgan; Paquet, Agnes; Lie, Yolanda; Weidler, Jodi M; Huang, Weidong; Winslow, John; Jankowski, Tomasz; Czartoryska-Arłukowicz, Bogumiła; Wysocki, Piotr J; Foszczyńska-Kłoda, Małgorzata; Radecka, Barbara; Litwiniuk, Maria M; Zok, Jolanta; Wiśniewski, Michał; Zuziak, Dorota; Biernat, Wojciech; Jassem, Jacek

2014-05-15

P95HER2 (p95) is a truncated form of the HER2, which lacks the trastuzumab-binding site and contains a hyperactive kinase domain. Previously, an optimal clinical cutoff of p95 expression for progression-free survival (PFS) and overall survival (OS) was defined using a quantitative VeraTag assay (Monogram Biosciences) in a training set of trastuzumab-treated metastatic breast cancer (MBC) patients. In the current study, the predictive value of the p95 VeraTag assay cutoff established in the training set was retrospectively validated for PFS and OS in an independent series of 240 trastuzumab-treated MBC patients from multiple institutions. In the subset of 190 tumors assessed as HER2-total (H2T)-positive using the quantitative HERmark assay (Monogram Biosciences), p95 VeraTag values above the predefined cutoff correlated with shorter PFS (HR = 1.43; P = 0.039) and shorter OS (HR = 1.94; P = 0.0055) where both outcomes were stratified by hormone receptor status and tumor grade. High p95 expression correlated with shorter PFS (HR = 2.41; P = 0.0003) and OS (HR = 2.57; P = 0.0025) in the hormone receptor-positive subgroup of patients (N = 78), but not in the hormone receptor-negative group. In contrast with the quantitative p95 VeraTag measurements, p95 immunohistochemical expression using the same antibody was not significantly correlated with outcomes. The consistency in the p95 VeraTag cutoff across different cohorts of patients with MBC treated with trastuzumab justifies additional studies using blinded analyses in larger series of patients. ©2014 American Association for Cancer Research.

A potential method using Ge{iPrNC[N(SiMe_3)_2]NiPr}{sub 2}, (Et{sub 3}Si){sub 2}Te and anhydrous hydrazine for germanium tellurides

Energy Technology Data Exchange (ETDEWEB)

Du, Liyong; Du, Shulei; Ding, Yuqiang [School of Chemical and Material Engineering, Jiangnan University, Wuxi (China)

2017-12-29

A germanium(II)-guanidine derivative of formula Ge{iPrNC[N(SiMe_3)_2]NiPr}{sub 2} (1) was synthesized and characterized by {sup 1}H NMR, {sup 13}C NMR, elemental analysis, and X-ray diffraction method. Thermal property was also studied to identify its thermal stability and volatility. More importantly, compound 1 was synthesized to develop a new method for germanium tellurides, where anhydrous hydrazine was introduced to prompt the activity of germanium(II) guanidines (or derivatives) towards (Et{sub 3}Si){sub 2}Te. Solution reaction of compound 1, (Et{sub 3}Si){sub 2}Te, and anhydrous hydrazine was investigated to pre-identify the feasibility of this combination for ALD process. The EDS data of the black precipitate from this reaction verified the potential of this method to manufacture germanium tellurides. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

75 FR 26746 - ONEOK Westex Transmission, L.L.C.; Notice of Baseline Filing

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2010-05-12

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. PR10-19-000] ONEOK Westex Transmission, L.L.C.; Notice of Baseline Filing May 5, 2010. Take notice that on April 29, 2010, ONEOK Westex Transmission, L.L.C. submitted its baseline filing of its Statement of Operating Conditions for transportation...

75 FR 51990 - CenterPoint Energy-Illinois Gas Transmission Company; Notice of Baseline Filing

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2010-08-24

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. PR10-80-000] CenterPoint Energy--Illinois Gas Transmission Company; Notice of Baseline Filing August 17, 2010. Take notice that on August 12, 2010, the applicant listed above submitted their baseline filing of its Statement of Operating...

Incommensurate magnetism in non-superconducting PrBa2Cu3O6.92

DEFF Research Database (Denmark)

Boothroyd, A.T.; Hill, J.P.; McMorrow, D.F.

1999-01-01

We report the discovery of incommensurate magnetic order in non-superconducting single crystals PrBa2Cu3O6.92. Resonant X-ray magnetic scattering at the Pr L-II and L-III edges and high resolution neutron diffraction were used to characterise the magnetic order on the different magnetic sublattices...

78 FR 62345 - Combined Notice of Filings #2

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2013-10-18

... Generator Status of Miami Wind I LLC. Filed Date: 10/9/13. Accession Number: 20131009-5053. Comments Due: 5... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Combined Notice of Filings 2 Take notice that the Commission received the following exempt wholesale generator filings: Docket Numbers: EG14-3...

26 CFR 1.7476-2 - Notice to interested parties.

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2010-04-01

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[Pr2(pdc3(Hpdc(H2O4]n·n(H3hp·8n(H2O, a One-Dimensional Coordination Polymer Containing PrO6N3 Tri-Capped Trigonal Prisms and PrO8N Mono-Capped Square Anti-Prisms (H2pdc = Pyridine 2,6-Dicarboxylic Acid, C7H5NO4; 3hp = 3-Hydroxy Pyridine, C5H5NO

Directory of Open Access Journals (Sweden)

Shahzad Sharif

2012-08-01

Full Text Available The synthesis, structure and some properties of the one-dimensional coordination polymer, [Pr2(pdc3(Hpdc]n·n(H3hp·8n(H2O, (H2pdc = pyridine 2,6-dicarboxylic acid, C7H5NO4; 3hp = 3-hydroxypyridine, C5H5NO are described. One of the Pr3+ ions is coordinated by two O,N,O-tridentate pdc2− ligands and one tridentate Hpdc− anion to generate a fairly regular PrO6N3 tri-capped trigonal prism, with the N atoms acting as the caps. The second Pr3+ ion is coordinated by one tridentate pdc2− dianion, four water molecules and two monodentate bridging pdc2− ligands to result in a PrO8N coordination polyhedron that approximates to a mono-capped square-anti-prism. The ligands bridge the metal-atom nodes into a chain, which extends in the [100] direction. The H3hp+ cation and uncoordinated water molecules occupy the inter-chain regions and an N–HLO and numerous O–HLO hydrogen bonds consolidate the structure. The H3hp+ species appears to intercalate between pendant pdc rings to consolidate the polymeric structure. Crystal data: 1 (C33H43N5O29Pr2, Mr = 1255.54, triclinic,  (No. 2, Z = 2, a = 13.2567(1 Å, b = 13.6304(2 Å, c = 13.6409(2 Å, α = 89.695(1°, β = 63.049(1°, γ = 86.105(1°, V = 2191.16(5 Å3, R(F = 0.033, wR(F2 = 0.084.

Photon cascade luminescence from Pr3+ ions in LiPrP4O12 polyphosphate

International Nuclear Information System (INIS)

Shalapska, T; Stryganyuk, G; Romanyshyn, Yu; Demchenko, P; Voloshinovskii, A; Trots, D; Gektin, A; Dorenbos, P

2010-01-01

The spectral-kinetic properties of luminescence from LiY 1-x Pr x P 4 O 12 (x = 1, 0.1) phosphors are studied in the 10-300 K temperature range upon excitation within the UV-VUV spectral range. The luminescence observed for LiPrP 4 O 12 at low temperatures is attributed to both intra-configurational 4f 2 → 4f 2 and inter-configurational 4f5d → 4f 2 radiative transitions of Pr 3+ . The temperature dependence of emission and the decay kinetics of Pr 3+ luminescence from LiY 1-x Pr x P 4 O 12 (x = 1, 0.1) phosphors are explained by temperature stimulated transitions from the 1 S 0 to the Pr 3+ 4f5d state. At low temperatures, the energy potential barrier between the 1 S 0 and 4f5d states is 0.014 eV for LiPrP 4 O 12 . The spectral overlap of the 1 S 0 and 4f5d states of Pr 3+ in LiY 0.9 Pr 0.1 P 4 O 12 determines the luminescence properties in the entire temperature range studied.

Scintillation properties of transparent Lu{sub 3}Al{sub 5}O{sub 12} (LuAG) ceramics doped with different concentrations of Pr{sup 3+}

Energy Technology Data Exchange (ETDEWEB)

Yanagida, Takayuki; Fukabori, Akihiro; Fujimoto, Yutaka; Kamada, Kei; Yokota, Yuui; Yoshikawa, Akira; Chani, Valery [IMRAM, Tohoku University, 2-1-1 Katahira Aoba-ku, 980-8577 Sendai (Japan); Ikesue, Akio [World Labo, Co. Ltd., Mutsuno 2-4-1, Atsuta, 456-0023 Nagoya (Japan); Kataoka, Jun [School of Advanced Science and Engineering,Waseda University, Ohkubo 3-4-1, Shinjuku, 169-0072 Tokyo (Japan)

2011-01-15

Transparent ceramics of Pr-doped (0.2 mol%, 0.6 mol%, 1 mol%, and 2 mol%) Lu{sub 3}Al{sub 5}O{sub 12} (LuAG) scintillators produced by the sintering method are discussed. These materials were cut to the specimens with physical dimensions of 5 x 5 x 2 mm{sup 3}. Similar size specimens were also prepared from Czochralski grown Pr:LuAG single crystals to compare scintillation properties. Their transmittance and radio luminescence spectra were evaluated. All specimens were highly transparent in wavelength range above 300 nm, and intense Pr{sup 3+} 5d-4f emission was detected around 310 and 370 nm under excitation with X-ray. Under {sup 137}Cs {gamma}-ray is irradiation, 2 keV photo-absorption peaks were also clearly observed in each sample. The Pr 0.6 mol% doped LuAG ceramics demonstrated highest light yield achievable among the ceramics, and it was half of that observed in the single crystals. Under pulse X-ray excitation, the decay time constants became faster when Pr concentration increased, and. the fastest decay ({proportional_to}5.7 ns time constant) was noticed in the 2 mol% doped ceramic. (copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

Electronic structure of layered ferroelectric high-k titanate Pr2Ti2O7

DEFF Research Database (Denmark)

Atuchin, V.V.; Gavrilova, T.A.; Grivel, Jean-Claude

2012-01-01

The spectroscopic parameters and electronic structure of binary titanate Pr2Ti2O7 have been studied by IR-, Raman and X-ray photoelectron spectroscopy (XPS) for the powder sample prepared by solid state synthesis. The spectral features of valence band and all constituent element core levels have...

Spectral analysis of Pr{sup 3+} doped germanate glasses modified by BaO and BaF{sub 2}

Energy Technology Data Exchange (ETDEWEB)

Pisarska, Joanna, E-mail: joanna.pisarska@us.edu.pl [University of Silesia, Institute of Chemistry, Szkolna 9 Street, 40-007 Katowice (Poland); Pisarski, Wojciech A. [University of Silesia, Institute of Chemistry, Szkolna 9 Street, 40-007 Katowice (Poland); Dorosz, Dominik; Dorosz, Jan [Bialystok University of Technology, Faculty of Electrical Engineering, Wiejska 45D Street, 15-351 Bialystok (Poland)

2016-03-15

Luminescence properties of Pr{sup 3+} ions in germanate glasses modified by BaF{sub 2} were investigated. Several luminescence bands originating to transitions from the {sup 3}P{sub 0} state to the lower-lying states of Pr{sup 3+} were registered under 450 nm excitation. The spectral analysis suggests that the positions of luminescence bands and their relative intensities are changed significantly with BaF{sub 2} content. The relative integrated luminescence intensities of {sup 3}P{sub 0}→{sup 3}H{sub 4} transition (blue) to the {sup 3}P{sub 0}→{sup 3}F{sub 2} transition (red) of Pr{sup 3+} ions strongly depend on fluoride modifier BaF{sub 2} in glass composition. The luminescence bands of Pr{sup 3+} ions are shifted to shorter wavelengths with increasing BaF{sub 2} content. - Highlights: • Praseodymium doped lead-free germanate glasses modified by BaF{sub 2} were prepared. • Emission spectra correspond to transitions from {sup 3}P{sub 0} state to lower-lying states of Pr{sup 3+}. • The relative emission band intensities of Pr{sup 3+} depend strongly on BaF{sub 2} content. • Emission bands of Pr{sup 3+} are shifted to shorter wavelengths with increasing BaF{sub 2} content.

75 FR 63452 - ONEOK Gas Storage, L.L.C.; Notice of Baseline Filing

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2010-10-15

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. PR11-67-001] ONEOK Gas Storage, L.L.C.; Notice of Baseline Filing October 7, 2010. Take notice that on October 1, 2010, ONEOK Gas Storage, L.L.C. submitted a revised baseline filing of its Statement of Operating Conditions for services...

78 FR 11639 - Houston Pipe Line Company LP; Notice of Petition for Rate Approval

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2013-02-19

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. PR13-31-000] Houston Pipe Line Company LP; Notice of Petition for Rate Approval Take notice that on February 1, 2013, Houston Pipe Line Company LP (HPL) filed for approval of rates for transportation service pursuant to section...

The Role of Social Relationships in PrEP Uptake and Use Among Transgender Women and Men Who Have Sex with Men.

Science.gov (United States)

Mehrotra, Megha L; Rivet Amico, K; McMahan, Vanessa; Glidden, David V; Defechereux, Patricia; Guanira, Juan V; Grant, Robert M

2018-05-12

Qualitative studies suggest that social relationships play an important role in HIV pre-exposure prophylaxis (PrEP) use, but there have been few quantitative assessments of the role of social relationships in PrEP uptake or adherence. We examined the association between disclosure of study participation or LGBT identity and PrEP use in the 1603 HIV-negative participants enrolled in the iPrEx OLE study. We also evaluated the association between LGBT social group involvement and PrEP use. Study participation disclosure to parents and LGBT identity disclosure to anyone in a participant's social network were associated with greater PrEP uptake. Study participation disclosure to partners was associated with higher probability of having protective PrEP drug concentrations compared [risk difference 0.15 95% CI (0.01, 0.30)]. For each additional type of LGBT organization a participant was involved in, the probability of PrEP uptake and having protective drug concentrations increased by 0.04 [95% CI (0.03, 0.06)] and 0.04 (95% CI (0.02, 0.07)] respectively. Overall, social context was associated with PrEP use in iPrEx OLE, and should be taken into consideration when designing future PrEP implementation programs.

Magnetic properties of two new compounds: Pr2Ni3Si5 and Ho2Ni3Si5

International Nuclear Information System (INIS)

Mazumdar, C.; Padalia, B.D.; Godart, C.

1994-01-01

Formation of two more new materials, Pr 2 Ni 3 Si 5 and Ho 2 Ni 3 Si 5 , of the series, R 2 Ni 3 Si 5 (R = rare earth and Y) and their magnetic properties are reported here. These materials crystallize in the orthorhombic U 2 Co 3 Si 5 -type structure (space group Ibam). Magnetic susceptibility measurement in the temperature range 5 K--300 K show that the compound Pr 2 Ni 3 Si 5 order antiferromagnetically at T N ∼ 8.5 K and Ho 2 Ni 3 Si 5 at ∼ 6 K. Considering T N (Gd 2 Ni 3 Si 5 ) ∼ 15 K, T N (Pr 2 Ni 3 Si 5 ) ∼ 8.5 K is rather high. The magnetic susceptibility of both of the materials, in the paramagnetic state, follows a Curie-Weiss law with effective moment close to that of the corresponding free trivalent rare earth ion

Phase diagrams of Pr-C system

International Nuclear Information System (INIS)

Eremenko, V.N.; Velikanova, T.Ya.; Gordijchuk, O.V.

1988-01-01

Results of the X-ray phase, metallographic and high-temperature differential thermal analysis are used for the first time to plot a diagram of the Pr-C system state. Carbides are formed in the system: Pr 2 C 3 with the bcc-structure of the Pu 2 C 3 type and with the period a 0 = 0.85722+-0.00026 within the phase region + 2 C 3 >, a 0 0.86078+-0.00016 nm - within the region 2 C 3 >+α-PrC 2 ; dimorphous PrC 2 : α-PrC 2 with the bct-structure of the CaC 2 type and periods a 0.38517+-0.00011, c 0 = 0.64337+-0.00019 nm; β-PrC 2 with the fcc-structure, probably, of KCN type. Dicarbide melts congruently at 2320 grad. C, forming eutectics with graphite at 2254+-6 grad. C and composition of 71.5% (at.)C. It is polymorphously transformed in the phase region 2 C 3 > + 2 > at 1145+-4 grad. C, and in the region 2 >+C at 1134+-4 grad. C. Sesquicarbide melts incongruently at 1545+-4 grad. C. The eutectic reaction L ↔ + 2 C 3 > occurs at 800+-4 grad. C, the eutectic composition ∼ 15% (at.)C. The temperature of the eutectoid reaction ↔ + 2 C 3 > is 675+-6 grad C. The limiting carbon solubility in β-Pr is about 8 and in α-Pr it is about 5% (at.)

The Pr and Ca Substitution in GdBa2Cu3O7- & delta

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H. S. H.

2001-12-01

Full Text Available   The granular Gd1-x-zPrxCazBa2Cu3O7-δ high-temperature cuprate samples with 0.0 ≤ x ≤ 0.3 and 0.0≤ x ≤ 0.35 are prepared by standard solid state reaction and characterized by XRD and SEM techniques. The BaCuO2 and impurity phases are less than 1% in the samples having high levels of pr and Ca concentrations. The electrical resistivity measurements show a nonlinear reduction in Tc(x,z=etc versus x. Moreover, the Tc(z curve with x=0 is nonlinear and aplateau appears at z≈ 0.05-0.015. For Pr-Ca-doped samples with a constant concentration of Pr, Tc increases with the increase of Ca up to an optimum value of Ca doping and then in decreases. Based on these observations, we suggest that hole filling and hole localization the main effects of Pr ion substiution. The magnetic measurements indicate that the value of Hc1 is in the order of 10 mT. The mangetoresistance measurements have been measured and analyzed. The superconducting transition region is broadened by the application of magnetic field. The experimental data near the onsen of superconductivity are fitted with the Ambegakor and Halperin (AH phase-slip model. We observe that the AH parameter,γ (H, depends not only on the temperature and the magnetic field, but also on the Pr and Ca ions concentrations. It is observed that the critical current density increases with Ca substitution and decreases with Pr substitution in Gd-123 system. We suggest that the Pr ion substitution probably enhances the weak link, but the Ca ion acts as flux pinning center in the GdPrCa-123 system.

Magnetic relaxation behaviour in Pr_2NiSi_3

International Nuclear Information System (INIS)

Pakhira, Santanu; Mazumdar, Chandan; Ranganathan, R.

2016-01-01

Time dependent isothemal remanent magnetizatin (IRM) behaviour for polycrystalline compound Pr_2NiSi_3 have been studied below its characteristic temperature. The compound undergoes slow magnetic relaxation with time. Along with competing interaction, non-magnetic atom disorder plays an important role in formation of non-equilibrium glassy like ground state for this compound.

78 FR 13662 - Kansas Gas Service, a Division of ONEOK, Inc.; Notice of Petition

Science.gov (United States)

2013-02-28

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. PR13-18-001] Kansas Gas Service, a Division of ONEOK, Inc.; Notice of Petition Take notice that on February 6, 2013, Kansas Gas... fully detailed in the petition. Any person desiring to participate in this rate filing must file in...

Thermodynamic assessment of the Pr-Zn binary system

International Nuclear Information System (INIS)

Huang, X.M.; Liu, L.B.; Zhang, L.G.; Jia, B.R.; Jin, Z.P.; Zheng, F.

2008-01-01

On the basis of available experimental data of phase diagram and thermodynamic properties, the Pr-Zn binary system has been optimized using the CALPHAD approach. The phases, including liquid and bcc A 2(βPr) were treated as substitutional solutions, while the intermetallic compounds, including PrZn, PrZn 2 , PrZn 3 , Pr 3 Zn 11 , Pr 13 Zn 58 , Pr 3 Zn 22 , Pr 2 Zn 17 and PrZn 11 were modeled as stoichiometric compounds. As the result of optimization, a set of self-consistent thermodynamic parameters has been obtained, which can be used to reproduce the reported experimental data

Mid-infrared emissions of Pr{sup 3+}-doped GeS{sub 2}–Ga{sub 2}S{sub 3}–CdI{sub 2} chalcohalide glasses

Energy Technology Data Exchange (ETDEWEB)

Lu, Chunfeng [State Key Laboratory of Transient Optics and Photonics, Xi’an Institute of Optics and precision Mechanics, Chinese Academy of Science (CAS), Xi’an, Shaanxi 710119 (China); Guo, Haitao, E-mail: guoht_001@opt.ac.cn [State Key Laboratory of Transient Optics and Photonics, Xi’an Institute of Optics and precision Mechanics, Chinese Academy of Science (CAS), Xi’an, Shaanxi 710119 (China); Xu, Yantao; Hou, Chaoqi; Lu, Min [State Key Laboratory of Transient Optics and Photonics, Xi’an Institute of Optics and precision Mechanics, Chinese Academy of Science (CAS), Xi’an, Shaanxi 710119 (China); He, Xin [School of Applied Physics and Materials, Wuyi University, Jiangmen, Guangdong 529020 (China); Wang, Pengfei; Li, Weinan [State Key Laboratory of Transient Optics and Photonics, Xi’an Institute of Optics and precision Mechanics, Chinese Academy of Science (CAS), Xi’an, Shaanxi 710119 (China); Peng, Bo, E-mail: bpeng@opt.ac.cn [State Key Laboratory of Transient Optics and Photonics, Xi’an Institute of Optics and precision Mechanics, Chinese Academy of Science (CAS), Xi’an, Shaanxi 710119 (China)

2014-12-15

Graphical abstract: ∼4.6 μm mid-infrared fluorescence emission from Pr{sup 3+} in the sulfide glass is successfully observed at room temperature excited by a 2.01 μm Tm{sup 3+}:YAG ceramic laser system. - Highlights: • Serial Pr{sup 3+}-doped GeS{sub 2}–Ga{sub 2}S{sub 3}–CdI{sub 2} chalcohalide glasses were synthesized. • ∼4.6 μm mid-infrared fluorescence from Pr{sup 3+} was observed at room temperature. • The compositional dependence of luminescence properties was studied. • Radiative properties have been determined using the Judd–Ofelt theory. - Abstract: For elucidation of the glass composition’s influence on the spectroscopic properties in the chalcohalide system and the discovery of a new material for applications in mid-infrared fiber-lasers, a serial Pr{sup 3+}-doped (100 − x)(0.8GeS{sub 2}·0.2Ga{sub 2}S{sub 3})xCdI{sub 2} (x = 5, 10, 15 and 20) chalcohalide glasses were prepared. ∼4.6 μm mid-infrared fluorescence emission from Pr{sup 3+} in the sulfide glass is successfully observed at room temperature excited by a 2.01 μm Tm{sup 3+}:YAG ceramic laser system, and the effective line-width of fluorescence band is 106–227 nm. Intense compositional dependence of mid-infrared emissions is found. The radiative rates of Pr{sup 3+} ions in these glasses were calculated by using the Judd–Ofelt theory.

Energy transfer in Pr3+ and Mn2+ co-doped SrB6O10 and SrB4O7

International Nuclear Information System (INIS)

Chen Yonghu; Yan Wuzhao; Shi Chaoshu

2007-01-01

The luminescent properties of Pr 3+ and Mn 2+ -doped SrB 6 O 10 and SrB 4 O 7 powder samples were investigated from the point of view of energy transfer between Pr 3+ and Mn 2+ . The emission from the 1 S 0 level of Pr 3+ was found in the SrB 6 O 10 :Pr 3+ sample as well as in the SrB 4 O 7 :Pr 3+ sample, indicating the 1 S 0 level is below the lowest 4f5d energy level in these hosts. The spectral overlaps between the emission spectra of Pr 3+ -doped samples and the excitation spectra of Mn 2+ -doped sample were found in both kinds of strontium borates. These spectral overlaps are in favor of the energy transfer from Pr 3+ to Mn 2+ . However, in the emission spectra of the SrB 6 O 10 :Pr 3+ , Mn 2+ , no indication of energy transfer was observed, though the emission spectra of SrB 4 O 7 :Pr 3+ , Mn 2+ did show evidence of energy transfer from Pr 3+ to Mn 2+ . The possible reasons were discussed

Effects of hole doping on the electronic transport properties of PrBa sub 1 sub . sub 8 Sr sub 0 sub . sub 2 Cu sub 3 O sub y and PrSr sub 2 Cu sub 2 sub . sub 7 Mo sub 0 sub . sub 3 O sub y

CERN Document Server

Yang, C F; Zhang, H

2002-01-01

We investigate the effect of Ca doping on the electronic transport properties and superconductivity of Pr sub 1 sub - sub x Ca sub x Ba sub 1 sub . sub 8 Sr sub 0 sub . sub 2 Cu sub 3 O sub y and Pr sub 1 sub - sub x Ca sub x Sr sub 2 Cu sub 2 sub . sub 7 Mo sub 0 sub . sub 3 O sub y systems. It is found that when PrBa sub 2 Cu sub 3 O sub y (Pr123) is in a highly localized state, the Ca doping mainly decreases the 4f-2p hybridized states and thus releases the holes into the CuO sub 2 planes. Whereas when Pr123 is in a less localized state, the Ca doping not only introduces holes into the CuO sub 2 planes, but also induces dramatic charge transfer. Our results suggest that only when the hole concentration in both the CuO chain and the CuO sub 2 planes reaches a proper value, can the superconductivity be restored in the Pr123 system.

Interplay of structural chemistry and magnetism in perovskites; A study of CaLn2Ni2WO9; Ln=La, Pr, Nd

Science.gov (United States)

Chin, Chun-Mann; Paria Sena, Robert; Hunter, Emily C.; Hadermann, Joke; Battle, Peter D.

2017-07-01

Polycrystalline samples of CaLn2Ni2WO9 (Ln=La, Pr, Nd) have been synthesized and characterised by a combination of X-ray and neutron diffraction, electron microscopy and magnetometry. Each composition adopts a perovskite-like structure with a 5.50, b 5.56, c 7.78 Å, β 90.1° in space group P21/n. Of the two crystallographically distinct six-coordinate sites, one is occupied entirely (Ln=Pr) or predominantly (Ln=La, Nd) by Ni2+ and the other by Ni2+ and W6+ in a ratio of approximately 1:2. None of the compounds shows long-range magnetic order at 5 K. The magnetometry data show that the magnetic moments of the Ni2+ cations form a spin glass below 30 K in each case. The Pr3+ moments in CaPr2Ni2WO9 also freeze but the Nd3+ moments in CaNd2Ni2WO9 do not. This behaviour is contrasted with that observed in other (A,A')B2B'O9 perovskites.

MOCVD of zirconium oxide from the zirconium guanidinate complex |ZrCp′{2-(iPrN)2CNMe2}2Cl

NARCIS (Netherlands)

Blackman, C.S.; Carmalt, C.J.; Moniz, S.J.A.; Potts, S.E.; Davies, H.O.; Pugh, D.C.

2009-01-01

Parallel to successful studies into use of [ZrCp'{¿ 2-(iPrN)2CNMe2} 2Cl] as a precursor to the deposition of zirconium carbonitride via CVD the same precursor was utilised for the MOCVD of thin films of ZrO 2 using borosilicate glass substrates. The deposited films were of mixed phase; films

Effect of Mg substitution on crystal structure and hydrogenation of Ce{sub 2}Ni{sub 7}-type Pr{sub 2}Ni{sub 7}

Energy Technology Data Exchange (ETDEWEB)

Iwase, Kenji, E-mail: fbiwase@mx.ibaraki.ac.jp [Department of Materials Science and Engineering, Ibaraki University, 4-12-1 Nakanarusawa, Hitachi 316-8511 (Japan); Mori, Kazuhiro [Research Reactor Institute, Kyoto University, 2-1010 Asashiro-nishi, Kumatori, Sennan, Osaka 590-0494 (Japan); Terashita, Naoyoshi [Japan Metals & Chemicals Co., Ltd., Nishiokitama-gun, Yamagata 999-1351 (Japan); Tashiro, Suguru; Suzuki, Tetsuya [Department of Materials Science and Engineering, Ibaraki University, 4-12-1 Nakanarusawa, Hitachi 316-8511 (Japan)

2017-03-15

The effect of Pr being substituted by Mg in Pr{sub 2}Ni{sub 7} with a Ce{sub 2}Ni{sub 7}-type structure was investigated by X-ray diffraction (XRD) and pressure−composition (P−C) isotherm measurements. The maximum hydrogen capacity of Pr{sub 2}Ni{sub 7} reached 1.24 H/M in the first absorption process. However, 0.61 H/M hydrogen remained in the sample after the first desorption and the reversible hydrogen capacity decreased to 0.63 H/M. Severe peak broadening was observed in the XRD profile of Pr{sub 2}Ni{sub 7}H{sub 5.4} after the first P−C isotherm cycle. The metal sublattice of Pr{sub 2}Ni{sub 7}H{sub 5.4} is deformed and changes from the Ce{sub 2}Ni{sub 7}-type structure to a lower symmetry during hydrogenation, with no detection of an amorphous phase. Pr{sub 1.5}Mg{sub 0.5}Ni{sub 7} consists of two phases: 80% Gd{sub 2}Co{sub 7}-type and 20% PuNi{sub 3}-type phases. Mg substitution leads to the relative stability of the Gd{sub 2}Co{sub 7}-type and PuNi{sub 3}-type structures. The Gd{sub 2}Co{sub 7}-type and PuNi{sub 3}-type structures are retained after the P-C isotherm. The reversible hydrogen capacity reached 1.05 H/M. The structural change during the hydrogen absorption−desorption cycle and the hydrogenation characteristics are changed by Mg atoms replacing Pr in the MgZn{sub 2}-type cell. - Graphical abstract: The maximum hydrogen capacity is 1.2 H/M in the first absorption process and the reversible capacity is 0.63 H/M.

Significant Suppression of CT Radiation-Induced DNA Damage in Normal Human Cells by the PrC-210 Radioprotector.

Science.gov (United States)

Jermusek, Frank; Benedict, Chelsea; Dreischmeier, Emma; Brand, Michael; Uder, Michael; Jeffery, Justin J; Ranallo, Frank N; Fahl, William E

2018-05-21

While computed tomography (CT) is now commonly used and considered to be clinically valuable, significant DNA double-strand breaks (γ-H2AX foci) in white blood cells from adult and pediatric CT patients have been frequently reported. In this study to determine whether γ-H2AX foci and X-ray-induced naked DNA damage are suppressed by administration of the PrC-210 radioprotector, human blood samples were irradiated in a CT scanner at 50-150 mGy with or without PrC-210, and γ-H2AX foci were scored. X-ray-induced naked DNA damage was also studied, and the DNA protective efficacy of PrC-210 was compared against 12 other common "antioxidants." PrC-210 reduced CT radiation-induced γ-H2AX foci in white blood cells to near background ( P 95% DNA damage. A systemic PrC-210 dose known to confer 100% survival in irradiated mice had no discernible effect on micro-CT image signal-to-noise ratio and CT image integrity. PrC-210 suppressed DNA damage to background or near background in each of these assay systems, thus supporting its development as a radioprotector for humans in multiple radiation exposure settings.

Phase diagram of Pr-P system

International Nuclear Information System (INIS)

Mironov, K.E.

1981-01-01

An area of the Pr-P system, adjoining to the Pr ordinate, is plotted up by the DTA method. Presence of P solid solution in Pr is established. Data on thermal stability of PrP, PrP 2 , PrP 5 and PrP 7 are generalized. The diagram of phase transformations in Pr-P system is plotted up proceeding from the whole complex of the data, presented. A supposition is made on a possible formation of solid solutions between the highest polyphosphide and phosphorus [ru

Final report for tank 241-AN-102, grab samples 2AN-95-1 through 2AN-95-6 and 102-AN-1 through 102-AN-4

International Nuclear Information System (INIS)

Esch, R.A.

1996-01-01

Ten grab samples (2AN-95-1, 2, 3, 4A, 5A; 102-AN-1, 2, 3(A), 3(B), and 4) and one field blank (2AN-95-6) were taken from tank 241-AN-102. In support of the safety screening program, total organic carbon and cyanide were performed as secondary analyses because the differential scanning calorimetry results exceeded the notification limit. These were compared to safety screening limits at a confidence level of 95%. Waste compatibility analyses were performed on the 3 supernate samples and the field blank from the latest sampling event. Results presented in the 45 day and in this report show that the waste in Tank 241-AN-1D2 has energetics greater than 480 J/g (dry) and total organic carbon > 3 wt%; however, with a moisture content > 17 wt%, the tank may be considered ''conditionally'' safe in accordance with the Data Quality Objective to Support Resolution of the Organic Complexant Safety Issue

Prevalência de baixo nível de atividade física em crianças pré-escolares.

Directory of Open Access Journals (Sweden)

Simone Storino Honda Barros

2012-06-01

A prática de atividades físicas (AF na infância tem papel decisivo no desen­volvimento motor e prevenção da obesidade infantil. Evidências disponíveis sugerem que há elevada prevalência de baixos níveis de AF em crianças, mas pouco se conhece sobre o nível de AF em pré-escolares. O objetivo do estudo foi identificar a prevalência e os fatores associados ao baixo nível de AF em pré-escolares. Estudo transversal realizado em escolas privadas da Cidade de Olinda (PE, com coleta de dados mediante entrevista “face a face” com os pais das crianças. Participaram do estudo 265 crianças (54,3% meninas com idade média de 4,9 anos (DP=0,8. Foram consideradas expostas a baixo nível de AF as crianças que não realizavam, no mínimo, 60 minutos/dia de AF ao ar livre. A análise dos dados foi efetuada mediante regressão logística, considerando o baixo nível de AF como desfecho. Os resultados mostram que 65,3% (IC95%: 9,4-70,8 das crianças foram classificadas como expostas a “baixo nível de AF”. Análises permitiram identificar que maior escolaridade paterna (OR=2,41; IC95%: 1,13-5,10, falta de espaços para jogos e brincadeiras na residência (OR=2,36; IC95%: 1,17-4,78 e estudar em período vespertino (OR=2,92; IC95%: 1,55-5,49 ou integral (OR=57,1; IC95%: 6,57-496,2 foram fatores associados a baixo nível de AF. Maior número de filhos foi identificado como fator de proteção em relação a baixo nível de AF (OR=0,49; IC95%: 0,26-0,93. Pode-se concluir que a proporção de crianças expostas a baixo nível de AF é alta em comparação aos es­tudos congêneres e fatores parentais e ambientais estão associados ao nível de atividade física na idade pré-escolar.

Electronic structure of PrBa2Cu3O7 within LSDA+U: Different self-consistent solutions

Directory of Open Access Journals (Sweden)

M R Mohammadizadeh

2009-08-01

Full Text Available  Based on the density functional theory and using the full-potential linearized augmented-plane-waves method the electronic structure of PrBa2Cu3O7 (Pr123 system was calculated. The rotationally invariant local spin density approximation plus Hubbard parameter U was employed for Pr(4f orbitals. One self-consistent solution more stable than the previous solution, which has been proposed by Liechtenstein and Mazin (LM, was found. In contrast to the LM solution, it can explain the results of the 17O NMR spectroscopy study of nonsuperconducting Pr123 samples. This new solution favors the suggestion that the pure Pr123 samples should be intrinsically superconductor and metal similar to the other RBa2Cu3O7 (R=Y or a rare earth element samples. The imperfections cause the superconducting holes are transferred to the nonsuperconducting hole states around the high-symmetry (π/a, π/b, kz line in the Brillouin zone and so, superconductivity is suppressed in the conventional samples. It predicts that the superconducting 2pσ holes in the O2 sites of nonsuperconducting Pr123 samples should be depleted and the ones in the O3 sites should be almost unchanged .

75 FR 65471 - Combined Notice of Filings No. 2

Science.gov (United States)

2010-10-25

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Combined Notice of Filings No. 2 Tuesday, September 7, 2010. Take notice that the Commission has received the following Natural Gas Pipeline Rate and... Tuesday, September 14, 2010. Docket Numbers: RP10-922-001. Applicants: Venice Gathering System, L.L.C...

77 FR 28375 - Eagle Rock Desoto Pipeline, L.P.; Notice of Petition for Rate Approval

Science.gov (United States)

2012-05-14

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. PR12-25-000] Eagle Rock Desoto Pipeline, L.P.; Notice of Petition for Rate Approval Take notice that on May 1, 2012, Eagle Rock Desoto Pipeline, L.P. (Desoto) filed a Rate Election pursuant to 284.123(b)(1) of the Commissions...

Electronic and optical properties of layered RE{sub 2}Ti{sub 2}O{sub 7} (RE = Ce and Pr) from first principles

Energy Technology Data Exchange (ETDEWEB)

Sayede, A. [Universite Lille Nord de France, F-59000 Lille (France); Khenata, R. [Laboratoire de Physique Quantique et de Modlisation Mathmatique, Universite de Mascara, Mascara, 29000 (Algeria); Chahed, A.; Benhelal, O. [Condensed Matter and Sustainable Development Laboratory, Djillali Liabes University of Sidi Bel-Abbes, Sidi Bel-Abbes 22000 (Algeria)

2013-05-07

We have studied the structural and electronic properties of Ce{sub 2}Ti{sub 2}O{sub 7} (CeTO) and Pr{sub 2}Ti{sub 2}O{sub 7} (PrTO) by first-principles density functional theory calculations. The computed structural parameters are in fairly good agreement with the available experimental findings. Band structure calculations using the GGA+U approach predict an insulating ground state for the herein studied compounds. The insulating band gaps of 2.00 eV and 2.83 eV are found for CeTO and PrTO, respectively. The analysis of the density of states reveals that the strongly localized RE 4f levels act as charge-trapping sites, predicting a lower photocatalytic activity for CeTO. We have also calculated the optical properties for both CeTO and PrTO. Based on these properties, it is predicted that these titanates are insensitive to ultra-violet radiation, while they are more sensitive to frequencies of the radiation in visible and early UV regions.

Electrocardiogram PR Interval Is a Surrogate Marker to Predict New Occurrence of Atrial Fibrillation in Patients with Frequent Premature Atrial Contractions.

Science.gov (United States)

Chun, Kwang Jin; Hwang, Jin Kyung; Choi, So Ra; Park, Seung-Jung; On, Young Keun; Kim, June Soo; Park, Kyoung-Min

2016-04-01

The clinical significance of prolonged PR interval has not been evaluated in patients with frequent premature atrial contractions (PACs). We investigated whether prolonged PR interval could predict new occurrence of atrial fibrillation (AF) in patients with frequent PACs. We retrospectively analyzed 684 patients with frequent PACs (> 100 PACs/day) who performed repeated 24-hour Holter monitoring. Prolonged PR interval was defined as longer than 200 msec. Among 684 patients, 626 patients had normal PR intervals (group A) and 58 patients had prolonged PR intervals (group B). After a mean follow-up of 59.3 months, 14 patients (24.1%) in group B developed AF compared to 50 patients (8.0%) in group A (P PR interval (hazard ratio [HR], 1.950; 95% CI, 1.029-3.698; P = 0.041), age (HR, 1.033; 95% CI, 1.006-1.060; P = 0.015), and left atrial (LA) dimension (HR, 1.061; 95% CI, 1.012-1.112; P = 0.015) were associated with AF occurrence. Prolonged PR interval, advanced age, and enlarged LA dimension are independent risk factors of AF occurrence in patients with frequent PACs.

Magnetotransport and magnetism in single-crystal PrBa2Cu3O7-δ

International Nuclear Information System (INIS)

Browning, V.M.; Osofsky, M.S.; Byers, J.M.; Ehrlich, A.C.; Dosseul, F.

1996-01-01

The PrBa 2 Cu 3 O 7-δ (Pr 123) system is known to exhibit antiferromagnetic ordering of the Cu spins in the Cu-O planes and chains, in addition to the observed antiferromagnetism due to the ordering of the Pr ions. The antiferromagnetism of the Cu-O planes is generally associated with the insulating nature of transport in Pr 123 and electrical conduction is believed to result through open-quote open-quote hopping close-quote close-quote transport between disordered Cu-O chain segments. However, the possible effects of magnetic ordering in the Cu-O chains on transport properties have not been discussed. If the Cu-O chains play a dominant role in the electrical transport (as suggested by many of the popular theories), then the magnetic ordering of the chains should also be seen in the transport properties. We present magnetization and magnetotransport measurements on single crystal Pr 123 samples which suggest that the magnetism associated with the Cu-O chains does indeed mediate transport in this system. These results confirm that the chains play a significant role in the transport properties and underscore the need for further study of the interplay between magnetism and transport in Pr 123

Superstructure formation in PrNi{sub 2}Al{sub 3} and ErPd{sub 2}Al{sub 3}

Energy Technology Data Exchange (ETDEWEB)

Eustermann, Fabian; Hoffmann, Rolf-Dieter [Muenster Univ. (Germany). Inst. fuer Anorganische und Analytische Chemie; Janka, Oliver [Muenster Univ. (Germany). Inst. fuer Anorganische und Analytische Chemie; Oldenburg Univ. (Germany). Inst. fuer Chemie

2017-09-01

The intermetallic phase ErPd{sub 2}Al{sub 3} was obtained by arc-melting of the elements and subsequent annealing for crystal growth. The sample was studied by X-ray diffraction on powders and single crystals. The structure of ErPd{sub 2}Al{sub 3} was refined from X-ray diffraction data and revealed a superstructure of PrNi{sub 2}Al{sub 3} - a CaCu{sub 5} derivative (P6/m, a=1414.3(1), c=418.87(3) pm wR=0.0820, 1060 F{sup 2} values, 48 variables). The same superstructure was subsequently found for PrNi{sub 2}Al{sub 3} (P6/m, a=1407.87(4), c=406.19(2) pm, wR=0.0499, 904 F{sup 2} values, 47 variables). In the crystal structure, the aluminium and transition metal atoms form a polyanionic network according to [T{sub 2}Al{sub 3}]{sup δ-}, while rare earth atoms fill cavities within the networks. They are coordinated by six transition metal and twelve aluminum atoms. In contrast to the PrNi{sub 2}Al{sub 3} type structure reported so far, two crystallographic independent rare-earth sites are found of which one (1b) is shifted by 1/2 z, causing a distortion in the structure along with a recoloring of the T and Al atoms in the network.

Electrical PR Interval Variation Predicts New Occurrence of Atrial Fibrillation in Patients With Frequent Premature Atrial Contractions.

Science.gov (United States)

Chun, Kwang Jin; Hwang, Jin Kyung; Park, Seung-Jung; On, Young Keun; Kim, June Soo; Park, Kyoung-Min

2016-04-01

Atrial fibrillation (AF) is associated with the autonomic nervous system (ANS), and fluctuation of autonomic tone is more prominent in patients with AF. As autonomic tone affects the heart rate (HR), and there is an inverse relationship between HR and PR interval, PR interval variation could be greater in patients with AF than in those without AF. The purpose of this study was to investigate the correlation between PR interval variation and new-onset AF in patients with frequent PACs.We retrospectively enrolled 207 patients with frequent PACs who underwent electrocardiographs at least 4 times during the follow-up period. The PR variation was calculated by subtracting the minimum PR interval from the maximum PR interval. The outcomes were new occurrence of AF and all-cause mortality during the follow-up period.During a median follow-up of 8.3 years, 24 patients (11.6%) developed new-onset AF. Univariate analysis showed that prolonged PR interval (PR interval > 200 ms, P = 0.021), long PR variation (PR variation > 36.5 ms, P = 0.018), and PR variation (P = 0.004) as a continuous variable were associated with an increased risk of AF. Cox regression analysis showed that prolonged PR interval (hazard ratio = 3.321, 95% CI 1.064-10.362, P = 0.039) and PR variation (hazard ratio = 1.013, 95% CI 1.002-1.024, P = 0.022) were independent predictors for new-onset AF. However, PR variation and prolonged PR interval were not associated with all-cause mortality (P = 0.465 and 0.774, respectively).PR interval variation and prolonged PR interval are independent risk factors for new-onset AF in patients with frequent PACs. However we were unable to determine a cut-off value of PR interval variation for new-onset AF.

Thermal expansion and magnetostriction in Pr(n+2)(n+1)Nin(n-1)+2Sin(n+1) compounds

International Nuclear Information System (INIS)

Jiles, D.C.; Song, S.H.; Snyder, J.E.; Pecharsky, V.K.; Lograsso, T.A.; Wu, D.; Pecharsky, A.O.; Mudryk, Ya.; Dennis, K.W.; McCallum, R.W.

2006-01-01

Thermal expansion and magnetostriction of members of a homologous series of compounds based on the alloy series Pr (n+2)(n+1) Ni n(n-1)+2 Si n(n+1) have been measured. The crystal structures of these compounds are closely interrelated because they form trigonal prismatic columns in which the number of trigonal prisms that form the base of the trigonal columns is determined by the value of n in the chemical formula. Two compositions were investigated, Pr 5 Ni 2 Si 3 and Pr 15 Ni 7 Si 10 , corresponding to n=3 and n=4, respectively. The results were analyzed and used to determine the location of magnetic phase transitions by calculating the magnetic contribution to thermal expansion using the Gruneisen-Debye theory. This allowed more precise determination of the magnetic transition temperatures than could be achieved using the total thermal expansion. The results show two phase transitions in each material, one corresponding to the Curie temperature and the other at a lower temperature exhibiting characteristics of a spin reorientation transition

Magnetic resistance in Tm(Ba2x Prx)Cu3 O7+δ

International Nuclear Information System (INIS)

Mokhtari, Z.; Akhavan, M.

2003-01-01

The magnetoresistance of single phase polycrystalline Tm(Ba 2x Pr x )Cu 3 O 7+δ samples have been studied within AH model. The derives power law dependence of pinning energy and critical current density to applied magnetic field (H -n ) shows that the power factor increases with the increases of Pr content, with the average value of n≅0.2. It shows that the Pr doping plays the role of weak link. It is noticeable that the behavior of x=0 samples. This maybe due to the intragrain properties of the sample

75 FR 39244 - Arizona Public Service Company, Sequent Energy Management, L.P.; Notice of Joint Petition for...

Science.gov (United States)

2010-07-08

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. PR10-45-000] Arizona Public Service Company, Sequent Energy Management, L.P.; Notice of Joint Petition for Clarification, or in the Alternative, Request for Limited Waiver June 30, 2010. Take notice that on June 25, 2010, Arizona Public...

Electrocardiographic PR prolongation and atrial fibrillation risk: a meta-analysis of prospective cohort studies.

Science.gov (United States)

Cheng, Min; Lu, Xiangfeng; Huang, Jianfeng; Zhang, Shu; Gu, Dongfeng

2015-01-01

Electrocardiographic PR interval prolongation is considered a benign condition, but recent studies have challenged the notion by demonstrating that prolonged PR interval is associated with an increased risk of atrial fibrillation (AF). The purpose of this study was to perform a meta-analysis of prospective cohort studies to evaluate the evidence supporting an association of prolonged PR interval with AF incidence. We searched the MEDLINE and EMBASE database (from inception to May 2014) supplemented by manual searches of references of relevant retrieved articles. Prospective cohort studies were included with hazard ratio (HR) of prolonged PR interval for incident AF. The search strategy yielded 6 cohort studies meeting eligibility criteria. A total of 328,932 participants were included, with 14,191 participants suffering from AF during follow-up. Pooled HRs of prolonged PR interval for incident AF was 1.30 (95% CI: 1.13 to 1.49) using random-effect model (I(2) = 30%). There was a significant difference of combined HRs between studies with and without adjustment for taking of AV nodal blocking agents in subgroup analysis. Sensitivity analysis supported the robustness of the results. Prolonged PR interval is not a totally benign condition but an independent risk factor for AF incidence. The mechanisms underlying the association of prolonged PR interval with AF incidence need further research. © 2014 Wiley Periodicals, Inc.

Systematic study of photoluminescence upon band gap excitation in perovskite-type titanates R 1/2Na1/2TiO3:Pr (R=La, Gd, Lu, and Y)

International Nuclear Information System (INIS)

Inaguma, Yoshiyuki; Tsuchiya, Takeshi; Katsumata, Tetsuhiro

2007-01-01

Pr 3+ -doped perovskites R 1/2 Na 1/2 TiO 3 :Pr (R=La, Gd, Lu, and Y) were synthesized, and their structures, optical absorption and luminescent properties were investigated, and the relationship between structures and optical properties are discussed. Optical band gap of R 1/2 Na 1/2 TiO 3 increases in the order R=La, Gd, Y, and Lu, which is primarily due to a decrease in band width accompanied by a decrease in Ti-O-Ti bond angle. Intense red emission assigned to f-f transition of Pr 3+ from the excited 1 D 2 level to the ground 3 H 4 state upon the band gap photo-excitation (UV) was observed for all compounds. The wavelength of emission peaks was red-shifted in the order R=La, Gd, Y, and Lu, which originates from the increase in crystal field splitting of Pr 3+ . This is attributed to the decrease in inter-atomic distances of Pr-O together with the inter-atomic distances (R, Na)-O, i.e., increase in covalency between Pr and O. The results indicate that the luminescent properties in R 1/2 Na 1/2 TiO 3 :Pr are governed by the relative energy level between the ground and excited state of 4f 2 for Pr 3+ , and the conduction and valence band, which is primarily dependent on the structure, e.g., the tilt of TiO 6 octahedra and the Pr-Ti inter-atomic distance and the site symmetry of Pr ion. - Graphical abstract: The red intense emission assigned to f-f transition of Pr 3+ from the excited 1 D 2 level to the ground 3 H 4 state upon the band gap photo-excitation (UV) was observed upon the band gap photo-excitation in perovskites R 1/2 Na 1/2 TiO 3 :Pr(R=La, Gd, Lu, and Y). It was found that the systematic changes in their luminescent properties are strongly dependent on the structure

Two-stage multipolar ordering in Pr T2Al20 Kondo materials

Science.gov (United States)

Freyer, Frederic; Attig, Jan; Lee, SungBin; Paramekanti, Arun; Trebst, Simon; Kim, Yong Baek

2018-03-01

Among heavy fermion materials, there is a set of rare-earth intermetallics with non-Kramers Pr3 +4 f2 moments which exhibit a rich phase diagram with intertwined quadrupolar orders, superconductivity, and non-Fermi liquid behavior. However, more subtle broken symmetries such as multipolar orders in these Kondo materials remain poorly studied. Here, we argue that multi-spin interactions between local moments beyond the conventional two-spin exchange must play an important role in Kondo materials near the ordered to heavy Fermi liquid transition. We show that this drives a plethora of phases with coexisting multipolar orders and multiple thermal phase transitions, providing a natural framework for interpreting experiments on the Pr(T) 2Al20 class of compounds.

Visible-to-UVC upconversion efficiency and mechanisms of Lu{sub 7}O{sub 6}F{sub 9}:Pr{sup 3+} and Y{sub 2}SiO{sub 5}:Pr{sup 3+} ceramics

Energy Technology Data Exchange (ETDEWEB)

Cates, Ezra L. [Department of Environmental Engineering and Earth Sciences, Clemson University, Anderson, SC 29625 (United States); Center for Optical Materials Science and Engineering Technologies, Clemson University, Anderson, SC 29625 (United States); Wilkinson, Angus P. [School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA 30332 (United States); Kim, Jae-Hong, E-mail: jaehong.kim@yale.edu [Department of Chemical and Environmental Engineering, Yale University, New Haven, CT 06511 (United States)

2015-04-15

Visible-to-UVC upconversion (UC) by Pr{sup 3+}-doped materials is a promising candidate for application to sustainable disinfection technologies, including light-activated antimicrobial surfaces and solar water treatment. In this work, we studied Pr{sup 3+} upconversion in an oxyfluoride host system for the first time, employing Lu{sub 7}O{sub 6}F{sub 9}:Pr{sup 3+} ceramics. Compared to the previously studied Y{sub 2}SiO{sub 5}:Pr{sup 3+} reference material, the oxyfluoride host resulted in a 5-fold increase in intermediate state lifetime, likely due to a lower maximum phonon energy; however, only a 60% gain in UC intensity was observed. To explain this discrepancy, luminescence spectral distribution and decay kinetics were studied in both phosphor systems. The Pr{sup 3+} 4f5d band energy distribution in each phosphor was found to play a key role by allowing or disallowing the occurrence of a previously unexplored UC mechanism, which had a significant impact on overall efficiency. - Highlights: • Visible-to-UVC upconversion by Pr{sup 3+} was studied in an oxyfluoride host matrix for the first time. • Lu{sub 7}O{sub 6}F{sub 9}:Pr{sup 3+} ceramics were synthesized and characterized. • Lu{sub 7}O{sub 6}F{sub 9}:Pr{sup 3+} shows more intense UV upconversion than Y{sub 2}SiO{sub 5}:Pr{sup 3+}, with differing mechanisms. • 4f5d band energy and {sup 1}D{sub 2} involvement are important in maximizing upconversion efficiency.

Bi3+–Pr3+ energy transfer processes and luminescent properties of LuAG:Bi,Pr and YAG:Bi,Pr single crystalline films

International Nuclear Information System (INIS)

Zorenko, Y.; Gorbenko, V.; Savchyn, V.; Zorenko, T.; Nikl, M.; Mares, J.A.; Beitlerova, A.; Jary, V.

2013-01-01

Absorption, cathodoluminescence, excitation spectra of photoluminescence (PL) and PL decay kinetics were studied at 300 K for the double doped with Bi 3+ –Pr 3+ and separately doped with Bi 3+ and Pr 3+ Lu 3 Al 5 O 12 (LuAG) and Y 3 Al 5 O 12 (YAG) single crystalline film (SCF) phosphors grown by the liquid phase epitaxy method. The emission bands in the UV range arising from the intrinsic radiative transitions of Bi 3+ based centers, and emission bands in the visible range, related to the luminescence of excitons localized around Bi 3+ based centers, were identified both in Bi–Pr and Bi-doped LuAG and YAG SCFs. The energy transfer processes from the host lattice simultaneously to Bi 3+ and Pr 3+ ions and from Bi 3+ to Pr 3+ ions were investigated. Competition between Pr 3+ and Bi 3+ ions in the energy transfer processes from the LuAG and YAG hosts was evidenced. The strong decrease of the intensity of Pr 3+ luminescence both in LuAG:Pr and YAG:Pr SCFs phosphors, grown from Bi 2 O 3 flux, is observed due to the quenching influence of Bi 3+ flux related impurity. Due to overlap of the UV emission band of Bi 3+ centers with the f–d absorption bands of Pr 3+ ions in the UV range and the luminescence of excitons localized around Bi ions with the f–f absorption bands of Pr 3+ ions in the visible range, an effective energy transfer from Bi 3+ ions to Pr 3+ ions takes place in LuAG:Bi,Pr and YAG:Bi,Pr SCFs, resulting in the appearance of slower component in the decay kinetics of the Pr 3+ d–f luminescence. -- Highlights: • Bi and Pr doped film phosphor grown by liquid phase epitaxy method. • Energy transfer from Bi 3+ to Pr 3+ ions. • Strong quenching of the Pr 3+ luminescence by Bi 3+ co-dopant

Diferencias de las prácticas sexuales entre hombres y mujeres, en estudiantes universitarios durante el primer semestre de 2013

Directory of Open Access Journals (Sweden)

Javier Martínez Torres

2014-03-01

Full Text Available Title: Sexual practices’s differences between men and women in college students during the first half of 2013El conocimiento de las prácticas sexuales en los adultos jóvenes es necesario para ejecutar acciones preventivas enfocadas a la disminución de enfermedades de transmisión sexual y embarazos no deseados. Materiales y métodos: Se realizó un estudio descriptivo trasversal con análisis de casos y controles, en estudiantes universitarios entre 18 y 26 años de edad, el tamaño de la muestra fue de 589 participantes. Resultados: De los 589 estudiantes se analizaron 502; la edad promedio de inicio de relaciones sexuales se dio a los 16,26 años. El 50,4% eran hombres; la práctica de relaciones sexuales anales fue de 37,9%, mientras que la práctica de relaciones sexuales orales fue del 70,9%. Al realizar asociaciones entre el género y comportamientos sexuales, se encontró que la práctica de sexo oral para los hombres es de O.R. 1,62 (I.C.95% 1,09 – 2,39, similar al sexo anal donde se estimó un O.R. 1,69 (I.C.95% 1,17 – 2,44. Al ajustarse se mostró que no hay diferencias estadísticamente significativas por género para sexo oral O.R.A 1,13 (I.C.95% 0,72 – 1,78 y para sexo anal O.R.A 1,30 (I.C.95% 0,84 – 6,39. Conclusiones: No hay diferencias estadísticamente significativas para las prácticas sexuales entre los dos géneros. (DUAZARY 2013 No. 2, 112 - 118AbstractThe knowledge of sexual practices in young adults is required to run preventive actions aimed at the reduction of transmitted sexual diseases and unwanted pregnancies. Materials and Methods: A descriptive cross-sectional study with case-control analysis was developed by selecting 589 college students between 18 and 26 years of age. Results: 502 of 589 students were analyzed; the average age of their first sexual intercourse occurred at 16.26 years. 50.4% of the sample was men; the practice of anal intercourse was 37.9%, while the practice of oral sex was 70

Sensitizing effects of ZnO quantum dots on red-emitting Pr3+-doped SiO2 phosphor

CSIR Research Space (South Africa)

Mbule, PS

2012-05-01

Full Text Available In this study, red cathodoluminescence (CL) ( emission=614 nm) was observed from Pr3+ ions in a glassy (amorphous) SiO2 host. This emission was enhanced considerably when ZnO quantum dots (QDs) were incorporated in the SiO2:Pr3+ suggesting...

Gender differences in the association between lifestyle behaviors and diabetes distress in a community sample of adults with type 2 diabetes.

Science.gov (United States)

Lipscombe, Carla; Smith, Kimberley J; Gariepy, Geneviève; Schmitz, Norbert

2016-03-01

The present study examined the association between moderate and severe diabetes distress (DD) and lifestyle behaviors (physical activity, smoking, alcohol consumption) in a community sample of adults with type 2 diabetes mellitus (T2DM). A total of 1971 adults with T2DM were recruited using mixed methods sampling. Participants were considered eligible if they had a doctor diagnosis of T2DM (≤10 years), were insulin naïve, aged 40-75 years, and were from Quebec, Canada. Participants provided information on DD, lifestyle behaviors, sociodemographic, and diabetes-related factors. Multinomial logistic regressions examined the association between moderate and severe DD and each lifestyle behavior, according to gender. Effect estimates can be interpreted as probability ratios (PR). In females, physical inactivity was associated with an increased likelihood of moderate distress (PR 2.2; 95% confidence interval [CI] 1.49-3.24) and severe distress (PR 1.80; 95% CI 1.00-3.24). In males, only severe distress was associated with physical inactivity (PR 1.92; 95% CI 1.00-3.66). Current smoking was associated with a greater probability of severe distress in males (PR 3.0; 95% CI 1.54-5.84) and females (PR 1.32; 95% CI 0.67-2.60); however this effect was stronger in males. No association was found between alcohol consumption and DD in females. In males, frequent alcohol consumption was associated with a reduced probability of moderate (PR 0.56; 95% CI 0.34-0.91) and severe distress (PR 0.47; 95% CI 0.21-1.06). The findings of this study suggest important gender differences in the association between DD and lifestyle behaviors. © 2015 Ruijin Hospital, Shanghai Jiaotong University School of Medicine and Wiley Publishing Asia Pty Ltd.

Crystal structure and magnetic properties of PrCo6.8-xCuxHf0.2 compounds

International Nuclear Information System (INIS)

Luo, J; Liang, J K; Guo, Y Q; Liu, Q L; Liu, F S; Yang, L T; Zhang, Y; Rao, G H

2004-01-01

The effects of Cu substitution on the crystal structure and magnetic properties of PrCo 6.8-x Cu x Hf 0.2 (x = 0-1.0) compounds were investigated by means of x-ray powder diffraction and magnetic measurements. The as-cast PrCo 6.8-x Cu x Hf 0.2 compounds crystallize in the TbCu 7 -type structure with the space group P6/mmm. The Curie temperature and magnetic anisotropy field decrease with increasing Cu content. A spin reorientation behaviour has been observed in the PrCo 6.8-x Cu x Hf 0.2 compounds. The addition of Cu weakens the anisotropy of the Co sublattice, leading to an increase in the spin reorientation temperature with increasing content of Cu

SYNTHESIS AND CHARACTERIZATION OF (MU-5-C5ME5)2TI(R)CL (R = ME, ET, NORMAL-PR, CH=CH2, PH, O-NORMAL-PR) AND THEIR SALT METATHESIS REACTIONS - THERMAL-DECOMPOSITION PATHWAYS OF (MU-5-C5ME5)2TI(ME)R' (R' = ET, CH=CH2, PH, CH2PH)

NARCIS (Netherlands)

LUINSTRA, GA; TEUBEN, JH

Complexes Cp*2Ti(R)Cl (Cp* = eta-5-C5Me5; R = Me (1), Et (2), n-Pr (3), CH=CH2 (4), Ph (5), O-n-Pr (6)) have been prepared by oxidation Of CP*2TiR with lead dichloride. Not every compound Cp*2Ti(R)Cl was accessible and for R = CH2CMe3 and CH2Ph reduction to Cp*2TiCl and R. was observed. Homolysis of

Synthesis and Characterization of (η5-C5Me5)2Ti(R)Cl (R = Me, Et, n-Pr, CH=CH2, Ph, O-n-Pr) and Their Salt Metathesis Reactions. Thermal Decomposition Pathways of (η5-C5Me5)2Ti(Me)R' (R' = Et, CH=CH2, Ph, CH2Ph)

NARCIS (Netherlands)

Luinstra, Gerrit A.; Teuben, Jan H.

1992-01-01

Complexes Cp*2Ti(R)Cl (Cp* = η5-C5Me5; R = Me (1), Et (2), n-Pr (3), CH=CH2 (41, Ph (5), O-n-Pr (6)) have been prepared by oxidation of Cp*2TiR with lead dichloride. Not every compound Cp*2Ti(R)Cl was accessible and for R = CH2CMe3 and CH2Ph reduction to Cp*2TiCl and R· was observed. Homolysis of

Electronic and magnetic properties of quasi-skutterudite PrCo2Ga8 compound

Science.gov (United States)

Ogunbunmi, Michael O.; Sondezi, Buyisiwe M.; Nair, Harikrishnan S.; Strydom, André M.

2018-05-01

PrCo2Ga8 is an orthorhombic quasi-skutterudite type compound which crystallizes in the CaCo2Al8 structure type, with space group Pbam (No. 55). The Pr3+ ion has a site symmetry of Cs which predicts a crystal electric field (CEF) level splitting into 9 singlets for J = 4. However, a phase transition at Tm = 1.28 K is observed in electrical resistivity and specific heat results and is reported in this paper. The electrical resistivity shows an upturn below Tm due to the superzone-gap formation. This transition is tuneable in fields and is suppressed to lower temperatures with applied magnetic fields. The electronic specific heat Cp(T) / T increases below Tm and reaches a value of 7.37 J/(mol K2) at 0.4 K. The Sommerfeld coefficient, γ extracted from the low temperature analysis of C4f(T) / T is 637 mJ/(mol K2) indicating a possible mass enhancement of the quasiparticles. The calculated entropy value of 3.05 J/(mol K) is recovered around Tm exhibiting almost 53% of Rln2, where R is the universal gas constant. Magnetic susceptibility results obeys the Curie-Weiss law for data above 100 K with an estimated effective magnetic moment, μeff = 3.37 μB/Pr and Weiss temperature, θp = -124 K.

RNi2B2C (R = Ho, Dy, Tb and Pr) single crystals grown by the cold copper crucible method

Science.gov (United States)

Durán, A.; Munoz, E.; Bernès, S.; Escudero, R.

2000-08-01

Single crystals of RNi2B2C (R = Ho, Dy, Tb, Pr) have been grown on cold copper crucibles in a high-frequency induction furnace. As a result, shiny metallic and brittle platelike single crystals were obtained. They were examined by x-ray and scanning electron microscopy with WDX/EDX for local composition analysis and show a very good crystallographic structure and compositions. Resistivity and dc magnetic measurements were performed to study superconducting and magnetic properties. Besides known electronic properties of the RNi2B2C family, we report for the first time results for PrNi2B2C single crystals successfully obtained by this technique.

Impedance and ac conductivity studies of Ba (Pr1/2Nb1/2) O3 ceramic

Indian Academy of Sciences (India)

Home; Journals; Bulletin of Materials Science; Volume 36; Issue 4. Impedance and a.c. conductivity studies of ... Abstract. Impedance and electrical conduction studies of Ba(Pr1/2Nb1/2)O3 ceramic prepared through conventional ceramic fabrication technique are presented. The crystal symmetry, space group and unit cell ...

L2 Learners’ Proficiency Development through Noticing Feedback

Directory of Open Access Journals (Sweden)

Seyed Saber Alavi

2015-10-01

Full Text Available This experimental study investigated the relationship between noticing of corrective feedback and L2 development considering the learners’ perspective on error correction. Specifically, it aimed to uncover the noticeability and effectiveness of recasts, prompts, a combination of the two, to determine a relationship between noticing of CF and learning of the past tense. The participants were four groups of college ESL learners (n = 40. Each group was assigned to a treatment condition, but the researcher taught the control group. CF was provided to learners in response to their mistakes in forming the past tense. While noticing of CF was assessed through immediate recall and questionnaire responses, learning outcomes were measured through picture description administered via pre-test, post-test, and delayed post-test design. Learner beliefs about CF were probed by means of a 40-item questionnaire. The results indicated that the noticeability of CF is dependent on the grammatical target it addresses and that the feedback techniques that push learners to self-correct alone or in combination with target exemplars are more effective in. In relation to the learning outcomes, the overall past tense accuracy increased more than that for questions, but there were no significant differences between the groups. Finally, in relation to the beliefs about CF, the participants’ responses centered on the importance of oral CF, recasts as CF technique, prompts as CF technique, and affective consequences of CF, two of which mediated the noticeability of the supplied CF, but none impacted the learning outcomes.

Prótesis totales y lesiones bucales en adultos mayores institucionalizados

Directory of Open Access Journals (Sweden)

Beatriz García Alpízar

2012-03-01

Full Text Available Fundamento: las prótesis dentales constituyen una alternativa al perderse los dientes, pero no están exentas de provocar daños, que junto a la susceptibilidad de los tejidos, provocada por el envejecimiento e inadecuados estilos de vida, pueden llevar a la aparición de lesiones bucales. Objetivo: describir las características de pacientes portadores de prótesis totales y su relación con las lesiones bucales. Métodos: estudio descriptivo, con 93 ancianos institucionalizados portadores de prótesis total. Se utilizaron las pruebas de chi cuadrado y el riesgo relativo para determinar la asociación entre las variables: edad, sexo, higiene, estado de conservación, tiempo y frecuencia de uso de la prótesis, necesidades de prótesis, tipo de lesión, localización, hábito de fumar, enfermedades sistémicas y medicamentos empleados. Resultados: el 78,5 % de los ancianos presentó lesiones relacionadas con el uso de la prótesis. La estomatitis subprótesis fue la lesión más frecuente. La presencia de lesiones bucales fue significativa en aquellos con 80 años y más (100 %. El 95,8 % tenían prótesis deterioradas, y en la totalidad de ellos, las prótesis tenían 21 años y más de uso. El riesgo de desarrollar lesiones fue 2,98 veces superior en aquellos con una higiene bucal deficiente. El 100 % de los ancianos diabéticos y anémicos presentaron lesiones. Conclusiones: las lesiones bucales estuvieron muy relacionadas con los factores locales: estado de conservación, higiene, tiempo de uso de las prótesis; y con factores generales como: incremento de la edad, enfermedades sistémicas y uso de medicamentos para su tratamiento.

PrPST, a Soluble, Protease Resistant and Truncated PrP Form Features in the Pathogenesis of a Genetic Prion Disease

Science.gov (United States)

Frid, Kati; Binyamin, Orli; Gabizon, Ruth

2013-01-01

While the conversion of PrPC into PrPSc in the transmissible form of prion disease requires a preexisting PrPSc seed, in genetic prion disease accumulation of disease related PrP could be associated with biochemical and metabolic modifications resulting from the designated PrP mutation. To investigate this possibility, we looked into the time related changes of PrP proteins in the brains of TgMHu2ME199K/wt mice, a line modeling for heterozygous genetic prion disease linked to the E200K PrP mutation. We found that while oligomeric entities of mutant E199KPrP exist at all ages, aggregates of wt PrP in the same brains presented only in advanced disease, indicating a late onset conversion process. We also show that most PK resistant PrP in TgMHu2ME199K mice is soluble and truncated (PrPST), a pathogenic form never before associated with prion disease. We next looked into brain samples from E200K patients and found that both PK resistant PrPs, PrPST as in TgMHu2ME199K mice, and “classical” PrPSc as in infectious prion diseases, coincide in the patient's post mortem brains. We hypothesize that aberrant metabolism of mutant PrPs may result in the formation of previously unknown forms of the prion protein and that these may be central for the fatal outcome of the genetic prion condition. PMID:23922744

PR interval prolongation in coronary patients or risk equivalent: excess risk of ischemic stroke and vascular pathophysiological insights.

Science.gov (United States)

Chan, Yap-Hang; Hai, Jo Jo; Lau, Kui-Kai; Li, Sheung-Wai; Lau, Chu-Pak; Siu, Chung-Wah; Yiu, Kai-Hang; Tse, Hung-Fat

2017-08-24

Whether PR prolongation independently predicts new-onset ischemic events of myocardial infarction and stroke was unclear. Underlying pathophysiological mechanisms of PR prolongation leading to adverse cardiovascular events were poorly understood. We investigated the role of PR prolongation in pathophysiologically-related adverse cardiovascular events and underlying mechanisms. We prospectively investigated 597 high-risk cardiovascular outpatients (mean age 66 ± 11 yrs.; male 67%; coronary disease 55%, stroke 22%, diabetes 52%) for new-onset ischemic stroke, myocardial infarction (MI), congestive heart failure (CHF), and cardiovascular death. Vascular phenotype was determined by carotid intima-media thickness (IMT). PR prolongation >200 ms was present in 79 patients (13%) at baseline. PR prolongation >200 ms was associated with significantly higher mean carotid IMT (1.05 ± 0.37 mm vs 0.94 ± 0.28 mm, P = 0.010). After mean study period of 63 ± 11 months, increased PR interval significantly predicted new-onset ischemic stroke (P = 0.006), CHF (P = 0.040), cardiovascular death (P 200 ms. Using multivariable Cox regression, PR prolongation >200 ms independently predicted new-onset ischemic stroke (HR 8.6, 95% CI: 1.9-37.8, P = 0.005), cardiovascular death (HR 14.1, 95% CI: 3.8-51.4, P PR interval predicts new-onset MI at the exploratory cut-off >162 ms (C-statistic 0.70, P = 0.001; HR: 8.0, 95% CI: 1.65-38.85, P = 0.010). PR prolongation strongly predicts new-onset ischemic stroke, MI, cardiovascular death, and combined cardiovascular endpoint including CHF in coronary patients or risk equivalent. Adverse vascular function may implicate an intermediate pathophysiological phenotype or mediating mechanism.

48 CFR 49.601-2 - Letter notice.

Science.gov (United States)

2010-10-01

... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Letter notice. 49.601-2 Section 49.601-2 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION CONTRACT MANAGEMENT... immediate complete spoilage of work-in-process having a definite commercial value, or (D) to prevent any...

8 CFR 1205.2 - Revocation on notice.

Science.gov (United States)

2010-01-01

... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Revocation on notice. 1205.2 Section 1205.2 Aliens and Nationality EXECUTIVE OFFICE FOR IMMIGRATION REVIEW, DEPARTMENT OF JUSTICE IMMIGRATION... the petitioner or self-petitioner. The petitioner or self-petitioner must be given the opportunity to...

The influence of Pr3+ co-doping on the photoluminescence and cathodoluminescence properties of SiO2:Eu3+/Tb3+

CSIR Research Space (South Africa)

Mhlongo, GH

2011-07-01

Full Text Available Tb3+-Pr3+, and Eu3+-Pr3+ ion pairs co-doped in a SiO2 matrix were prepared by a sol-gel method. Co-doping of Eu3+ and Tb3+ ions with Pr3+ in SiO2 resulted in the quenching of Eu3+ and Tb3+ emissions with increasing Pr3+ concentrations. The quenching...

Theory of the 4d → 2p X-ray emission spectroscopy in Ce2O3, Pr2O3 and Dy2O3

International Nuclear Information System (INIS)

Tanaka, Satoshi; Ogasawara, Haruhiko; Okada, Kozo; Kotani, Akio.

1995-01-01

The 4d → 2p X-ray emission spectra (XES) of Ce 2 O 3 , Pr 2 O 3 and Dy 2 O 3 have been calculated with an impurity Anderson model with the full multiplet couplings, following the Kramers-Heisenberg formula in the second order optical process. Experimental results have been well reproduced with this model by using a constant value for the 4d core hole lifetime damping Γ(4d) in the case of Ce 2 O 3 and Pr 2 O 3 , while in the case of Dy 2 O 3 it is necessary to take into account the term dependence of Γ(4d), which is consistent with the previous theoretical analyses of 4d X-ray photoemission spectra. It was also shown that both the spin-orbit couplings of the 4d core level in the final state and the 4f level in the initial state are key factors to cause the branching ratio in the L γ line larger than that in the L β line. The phase matching of the wave functions between the intermediate and final states smears out the hybridization effect in the 4d → 2p XES in Ce 2 O 3 and Pr 2 O 3 . (author)

The Influence of Socioeconomic Status on Racial/Ethnic Disparities among the ER/PR/HER2 Breast Cancer Subtypes

International Nuclear Information System (INIS)

Parise, C. A.; Caggiano, V.Caggiano

2015-01-01

Background. The eight ER/PR/HER2 breast cancer subtypes vary widely in demographic and clinico pathologic characteristics and survival. This study assesses the contribution of SES to the risk of mortality for blacks, Hispanics, Asian/Pacific Islanders, and American Indians when compared with white women for each ER/PR/HER2 subtype. Methods. We identified 143,184 cases of first primary female invasive breast cancer from the California Cancer Registry between 2000 and 2012. The risk of mortality was computed for each race/ethnicity within each ER/PR/HER2 subtype. Models were adjusted for tumor grade, year of diagnosis, and age. SES was added to a second set of models. Analyses were conducted separately for each stage. Results. Race/ethnicity did not contribute to the risk of mortality for any subtype in stage 1 when adjusted for SES. In stages 2, 3, and 4, race/ethnicity was associated with risk of mortality and adjustment for SES changed the risk only in some subtypes. SES reduced the risk of mortality by over 45% for American Indians with stage 2 ER+/PR+/HER2-cancer, but it decreased the risk of mortality for blacks with stage 2 triple negative cancer by less than 4%. Conclusions. Racial/ethnic disparities do not exist in all ER/PR/HER2 subtypes and, in general, SES modestly alters these disparities.

Prion Protein Does Not Confer Resistance to Hippocampus-Derived Zpl Cells against the Toxic Effects of Cu2+, Mn2+, Zn2+ and Co2+ Not Supporting a General Protective Role for PrP in Transition Metal Induced Toxicity.

Science.gov (United States)

Cingaram, Pradeep Kumar Reddy; Nyeste, Antal; Dondapati, Divya Teja; Fodor, Elfrieda; Welker, Ervin

2015-01-01

The interactions of transition metals with the prion protein (PrP) are well-documented and characterized, however, there is no consensus on their role in either the physiology of PrP or PrP-related neurodegenerative disorders. PrP has been reported to protect cells from the toxic stimuli of metals. By employing a cell viability assay, we examined the effects of various concentrations of Cu2+, Zn2+, Mn2+, and Co2+ on Zpl (Prnp-/-) and ZW (Prnp+/+) hippocampus-derived mouse neuronal cells. Prnp-/- Zpl cells were more sensitive to all four metals than PrP-expressing Zw cells. However, when we introduced PrP or only the empty vector into Zpl cells, we could not discern any protective effect associated with the presence of PrP. This observation was further corroborated when assessing the toxic effect of metals by propidium-iodide staining and fluorescence activated cell sorting analysis. Thus, our results on this mouse cell culture model do not seem to support a strong protective role for PrP against transition metal toxicity and also emphasize the necessity of extreme care when comparing cells derived from PrP knock-out and wild type mice.

Crystal structure of PrOHSO4

International Nuclear Information System (INIS)

Fahey, J.A.; Williams, G.J.B.; Haschke, J.M.

1979-01-01

PrOHSO 4 was prepared by hydrothermal reaction of Pr(OH) 3 with Pr 2 (SO 4 ) 3 x H 2 O at 450 to 500 0 C and 1,200 +- 200 atm water pressure. The space group is P2 1 /c; the cell parameters are a = 4.488, b = 12.495, c = 7.091 A, β = 111.08, Z = 4, d/sub x/ = 4.49 g/cm 3 . Atomic coordinates and anisotropic thermal parameters are tabulated. A stereoscopic protection of the cation coordination sphere is shown and discussed. 2 figures, 3 tables

Validation of PR interval length as a criterion for development of atrial fibrillation in non-Hispanic whites, African Americans and Hispanics.

Science.gov (United States)

Shulman, Eric; Aagaard, Philip; Kargoli, Faraj; Hoch, Ethan; Zheng, Laura; Di Biase, Luigi; Fisher, John; Gross, Jay; Kim, Soo; Ferrick, Kevin; Krumerman, Andrew

2015-01-01

PR interval prolongation on electrocardiogram (ECG) increases the risk of atrial fibrillation (AF). Non-Hispanic Whites are at higher risk of AF compared to African Americans and Hispanics. However, it remains unknown if prolongation of the PR interval for the development of AF varies by race/ethnicity. Therefore, we determined whether race affects the PR interval length's ability to predict AF and if the commonly used criterion of 200 ms in AF prediction models can continue to be used for non-White cohorts. This is a retrospective epidemiological study of consecutive inpatient and outpatients. An ECG database was initially interrogated. Patients were included if their initial ECG demonstrated sinus rhythm and had two or more electrocardiograms and declared a race and/or ethnicity as non-Hispanic White, African American or Hispanic. Development of AF was stratified by race/ethnicity along varying PR intervals. Cox models controlled for age, gender, race/ethnicity, systolic blood pressure, BMI, QRS, QTc, heart rate, murmur, treatment for hypertension, heart failure and use of AV nodal blocking agents to assess PR interval's predictive ability for development of AF. 50,870 patients met inclusion criteria of which 5,199 developed AF over 3.72 mean years of follow-up. When the PR interval was separated by quantile, prolongation of the PR interval to predict AF first became significant in Hispanic and African Americans at the 92.5th quantile of 196-201 ms (HR: 1.42, 95% CI: 1.09-1.86, p=0.01; HR: 1.32, 95% CI: 1.07-1.64, p=0.01, respectively) then in non-Hispanic Whites at the 95th quantile at 203-212 ms (HR: 1.24, 95% CI: 1.24-1.53, p=0.04). For those with a PR interval above 200 ms, African Americans had a lower risk than non-Hispanic Whites to develop AF (HR: 0.80, 95% CI: 0.64-0.95, p=0.012), however, no significant difference was demonstrated in Hispanics. This is the first study to validate a PR interval value of 200 ms as a criterion in African Americans and

Impact of larger rare earth Pr{sup 3+} ions on the physical properties of chemically derived Pr{sub x}CoFe{sub 2−x}O{sub 4} nanoparticles

Energy Technology Data Exchange (ETDEWEB)

Pachpinde, A.M.; Langade, M.M. [Department of Chemistry, Jawahar Art Science and Commerce College Andur, Osmanabad, MS (India); Lohar, K.S.; Patange, S.M. [Materials Research Laboratory, Srikrishna Mahavidyalaya Gunjoti, Omerga, Osmanabad 413 613, MS (India); Shirsath, Sagar E., E-mail: shirsathsagar@hotmail.com [Spin Device Technology Center, Department of Information Engineering, Shinshu University, Nagano 380 8553 (Japan)

2014-01-31

Highlights: • Rare earth Pr{sup 3+} substituted CoFe{sub 2}O{sub 4}. • Sol–gel auto combustion synthesis. • XRD and IR spectra reveal the spinel structure. • Magnetization and coercivity increased with Pr{sup 3+} substitution. - Abstract: Rare earth Pr{sup 3+} ions with its larger ionic radii substituted CoFe{sub 2}O{sub 4} nanoparticles with x ranging from 0.0 to 0.1 were synthesized by sol–gel auto-combustion chemical method. Powder X-ray diffraction (XRD), scanning electron microscopy (SEM), infrared spectroscopy (IR) and vibrating sample magnetometer (VSM) were employed to characterize the physical properties of these ferrite nanoparticles. XRD pattern reveals the formation of cubic spinel ferrite with the signature of PrFeO{sub 3} phases for x ⩾ 0.05. SEM images show that the synthesized samples are in good homogeneity with uniformly distributed grain. The results of IR spectroscopy analysis indicated that the functional groups of cobalt spinel ferrite were formed during the sol–gel process. The cations distribution between the tetrahedral (A-site) and octahedral sites (B-site) has been estimated by XRD analysis. Room temperature magnetic measurement shows saturation magnetization and coercivity increased from 54.7 to 64.2 emu/g and 644 to 1013 Oe, respectively with the increasing Pr{sup 3+} substitution.

Praseodymium valency from crystal structure in Pr-Ba-Cu-O and (Y-Pr)-Ba-Cu-O single crystals

International Nuclear Information System (INIS)

Collin, G.; Albouy, P.A.; Monod, P.; Ribault, M.

1990-01-01

The substitution of Pr to Y leads to materials with a general formula (Y 1-v Pr v ) (Ba 2-x Pr x ) (Cu 3-y vac y ) O 6+x/2-y+z and with a structural transition around v + x' ∼ 0.5. For v + x 0.5 the crystals are tetragonal, La 1.5 Ba 1.5 Cu 3 O 7±z type, with the characteristic tri-twinning of this phase. The Pr valency, in the range 3-3.2 + depending on preparation conditions, is determined from interatomic distances. Orthorhombic crystals of Pr Ba Cu O prepared at high temperatures exhibit a high amount of defects, y ∼ 0.25 on the Cu(1) site and are semiconductors with a T -1/4 activation law attributed to the praseodymium valence fluctuation

OXIDATIVE-REFORMING OF METHANE AND PARTIAL OXIDATION OF METHANE REACTIONS OVER NiO/PrO2/ZrO2 CATALYSTS: EFFECT OF NICKEL CONTENT

Directory of Open Access Journals (Sweden)

Y. J. O. Asencios

Full Text Available Abstract In this work the behavior of NiO-PrO2-ZrO2 catalysts containing various nickel loadings was evaluated in the partial oxidation of methane and oxidative-reforming reactions of methane. The catalysts were characterized by X-Ray Diffraction Analysis (in situ-XRD, Temperature Programmed Reduction (H2-TPR, Scanning Electron Microscopy (SEM/EDX and Adsorption-Desorption of nitrogen (BET area. The reactions were carried out at 750 °C and 1 atm for 5 hours. The catalysts were studied with different nickel content: 0, 5, 10 and 15% (related to total weight of catalyst, wt%. In both reactions, the catalyst containing the mixture of the three oxides (NiO/PrO2/ZrO2 with 15% nickel (15NiPrZr catalyst showed the best activity for the conversion of the reactants into Syngas and showed high selectivity for H2 and CO. The results suggest that the promoter PrO2 and the Niº centers are in a good proportion in the catalyst with 15% Ni. Our results showed that low nickel concentrations in the catalyst led to high metallic dispersion; however, very low nickel concentrations did not favor the methane transformation into Syngas. The catalyst containing only NiO/ZrO2 in the mixture was not sufficient for the catalysis. The presence of the promoter PrO2 was very important for the catalysis of the POM.

Breast Cancer Survival Defined by the ER/PR/HER2 Subtypes and a Surrogate Classification according to Tumor Grade and Immunohistochemical Biomarkers

Directory of Open Access Journals (Sweden)

Carol A. Parise

2014-01-01

Full Text Available Introduction. ER, PR, and HER2 are routinely available in breast cancer specimens. The purpose of this study is to contrast breast cancer-specific survival for the eight ER/PR/HER2 subtypes with survival of an immunohistochemical surrogate for the molecular subtype based on the ER/PR/HER2 subtypes and tumor grade. Methods. We identified 123,780 cases of stages 1–3 primary female invasive breast cancer from California Cancer Registry. The surrogate classification was derived using ER/PR/HER2 and tumor grade. Kaplan-Meier survival analysis and Cox proportional hazards modeling were used to assess differences in survival and risk of mortality for the ER/PR/HER2 subtypes and surrogate classification within each stage. Results. The luminal B/HER2− surrogate classification had a higher risk of mortality than the luminal B/HER2+ for all stages of disease. There was no difference in risk of mortality between the ER+/PR+/HER2− and ER+/PR+/HER2+ in stage 3. With one exception in stage 3, the ER-negative subtypes all had an increased risk of mortality when compared with the ER-positive subtypes. Conclusions. Assessment of survival using ER/PR/HER2 illustrates the heterogeneity of HER2+ subtypes. The surrogate classification provides clear separation in survival and adjusted mortality but underestimates the wide variability within the subtypes that make up the classification.

X-ray-scattering study of copper magnetism in nonsuperconducting PrBa2Cu3O6.92

DEFF Research Database (Denmark)

Hill, J.P.; McMorrow, D.F.; Boothroyd, A.T.

2000-01-01

X-ray magnetic scattering from ordered Cu spins has been observed in a high-T-c compound. The measurements were made on the anomalous cuprate PrBa2Cu3O6.92 with x-ray photon energies tuned in the vicinity of the Cu K edge. The high wave-vector resolution enabled us to observe an incommensurate...... double-Q Cu spin structure below T-Pr = 19 K that forms as a result of coupling between the magnetically ordered Cu and Pr sublattices. Above T-Pr, the Cu ordering is commensurate, ruling out static spin-charge stripe order as an explanation for the absence of superconductivity in this material....

Magnetocaloric effect and other low-temperature properties of Pr2Pt2 In

Science.gov (United States)

Mboukam, J. J.; Sondezi, B. M.; Tchokonté, M. B. Tchoula; Bashir, A. K. H.; Strydom, A. M.; Britz, D.; Kaczorowski, D.

2018-05-01

We report on X-ray diffraction, electrical transport, heat capacity and magnetocaloric effect measurements of a polycrystalline sample of Pr2Pt2 In . The compound forms in the tetragonal Mo2FeB2 type structure and orders ferromagnetically at TC=9 K. In the ordered state, its thermodynamic and electrical transport properties are dominated by magnon contributions with an energy gap of about 8 K in the spin-wave spectrum. The magnitude of magnetocaloric effect is similar to the values reported for most rare-earth based intermetallics. Characteristic behavior of the isothermal magnetic entropy change maximum points to a second-order character of the ferromagnetic phase transition in the compound studied.

Modelling the optical bleaching of the thermoluminescence of K2YF5:Pr3+

International Nuclear Information System (INIS)

Marcazzó, J.; Santiago, M.; Khaidukov, N.; Caselli, E.

2012-01-01

Optical bleaching of the thermoluminescence (TL) curve of K 2 YF 5 :Pr 3+ has been observed after optically stimulated luminescence (OSL) readout of pre-irradiated crystals. The traps being responsible for the TL signal are not emptied completely by the optical stimulation. Furthermore, if the illumination time is increased a constant intensity level of the residual TL glow curve is eventually achieved. On the other hand, if the low temperature peak of the glow curve is thermally cleaned, no subsequent OSL is measured. This behavior has been successfully explained by assuming that part of the electrons in the trap being responsible for the low temperature glow peak of K 2 YF 5 :Pr 3+ recombine with holes via localized transitions during optical stimulation. During TL all trapped electrons recombine via delocalized transitions. Simulations have been carried out in order to demonstrate the feasibility of the model. - Highlights: ► The optical bleaching of the thermoluminescence of K2YF5:Pr 3+ has been studied. ► A model accounting for the optical bleaching has been put forward. ► Thermoluminescence occurs via delocalized transitions. ► Localized transitions occur during optical stimulation.

Lifestyle factors associated with type 2 diabetes and use of different glucose-lowering drugs: cross-sectional study.

Directory of Open Access Journals (Sweden)

Sinna P Ulrichsen

Full Text Available To examine the lifestyle profile among persons with and without Type 2 diabetes mellitus (DM and among users of different glucose-lowering drugs.We used questionnaire data from a Danish health survey and identified presence of Type 2 DM and use of medications through medical databases. We calculated age- and gender-standardized prevalence ratios (PRs of lifestyle factors according to Type 2 DM and different glucose-lowering drugs.Of 21,637 survey participants aged 25-79 years, 680 (3% had Type 2 DM (median age 63 years with a median diabetes duration of 5 years. Participants with Type 2 DM had a substantially higher prevalence of obesity (36% vs. 13%, PR: 3.1, 95% confidence interval (CI: 2.8-3.6, yet more reported to eat a very healthy diet (25% vs. 21%, PR: 1.2, 95% CI: 1.0-1.4 and to exercise regularly (67% vs. 53%, PR: 1.3, 95% CI: 1.2-1.4. Also, fewer were current smokers or had high alcohol intake. When compared with metformin users, obesity was substantially less prevalent in users of sulfonylurea (PR: 0.5, 95% CI: 0.4-0-8, and insulin and analogues (PR: 0.4, 95% CI: 0.3-0.7. Tobacco smoking was more prevalent in sulfonylurea users (PR: 1.4, 95% CI: 0.9-2.1 compared with metformin users. We found no material differences in physical exercise, diet or alcohol intake according to type of glucose-lowering drug.Type 2 DM patients are substantially more obese than other individuals, but otherwise report to have a healthier lifestyle. Metformin use is strongly associated with obesity, whereas sulfonylurea use tends to be associated with tobacco smoking.

Luminescence, scintillation, and energy transfer in SiO{sub 2}-Al{sub 2}O{sub 3}-B{sub 2}O{sub 3}-Gd{sub 2}O{sub 3}:Ce{sup 3+},Pr{sup 3+} glasses

Energy Technology Data Exchange (ETDEWEB)

Lertloypanyachai, Prapon; Chewpraditkul, Weerapong; Pattanaboonmee, Nakarin [Department of Physics, King Mongkut' s University of Technology Thonburi, Bangkok (Thailand); Chen, Danping [Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai (China); Babin, Vladimir; Beitlerova, Alena; Nikl, Martin [Institute of Physics, AS CR, Prague (Czech Republic)

2017-09-15

Ce{sup 3+},Pr{sup 3+}-codoped SiO{sub 2}-Al{sub 2}O{sub 3}-B{sub 2}O{sub 3}-Gd{sub 2}O{sub 3} glasses (SABG:Ce,Pr) were prepared by melt quenching under a CO reducing atmosphere. Luminescence properties were investigated under UV and X-ray excitations. A dominant emission band at 430 nm belonging to the Ce{sup 3+}:5d{sub 1} → 4f transition was observed in the photo- and radio-luminescence spectra. The energy transfer occurs from this Ce{sup 3+} band toward the {sup 3}P{sub J} levels of Pr{sup 3+} with an efficiency of up to 24%, followed by the reduction of integrated luminescence intensity with an increasing Pr{sup 3+} concentration. This result is attributed to the increase in the reabsorption of Ce{sup 3+} luminescence and the non-radiative energy transfer toward the {sup 3}P{sub J} levels of Pr{sup 3+}. The cross-relaxation process within the Pr{sup 3+} pairs can further diminish the total luminescence yield at high Pr{sup 3+} concentrations. The integral scintillation efficiency and light yield measurements were carried out and compared to the reference Bi{sub 4}Ge{sub 3}O{sub 12} (BGO) crystal. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Prüfungen zur Beurteilung der Brandgefahr; Anleitung für die Aufstellung von Anforderungen und Prüfbestimmungen zur Beurteilung der Brandgefahr von elektrotechnischen Erzeugnissen; 1-2: Anleitung für Bauelemente der Elektronik; Identisch mit IEC 60695-1-2, Ausgabe 1982

CERN Document Server

Deutsches Institut für Normung. Berlin

1986-01-01

Prüfungen zur Beurteilung der Brandgefahr; Anleitung für die Aufstellung von Anforderungen und Prüfbestimmungen zur Beurteilung der Brandgefahr von elektrotechnischen Erzeugnissen; 1-2: Anleitung für Bauelemente der Elektronik; Identisch mit IEC 60695-1-2, Ausgabe 1982

PrP(ST), a soluble, protease resistant and truncated PrP form features in the pathogenesis of a genetic prion disease.

Science.gov (United States)

Friedman-Levi, Yael; Mizrahi, Michal; Frid, Kati; Binyamin, Orli; Gabizon, Ruth

2013-01-01

While the conversion of PrP(C) into PrP(Sc) in the transmissible form of prion disease requires a preexisting PrP(Sc) seed, in genetic prion disease accumulation of disease related PrP could be associated with biochemical and metabolic modifications resulting from the designated PrP mutation. To investigate this possibility, we looked into the time related changes of PrP proteins in the brains of TgMHu2ME199K/wt mice, a line modeling for heterozygous genetic prion disease linked to the E200K PrP mutation. We found that while oligomeric entities of mutant E199KPrP exist at all ages, aggregates of wt PrP in the same brains presented only in advanced disease, indicating a late onset conversion process. We also show that most PK resistant PrP in TgMHu2ME199K mice is soluble and truncated (PrP(ST)), a pathogenic form never before associated with prion disease. We next looked into brain samples from E200K patients and found that both PK resistant PrPs, PrP(ST) as in TgMHu2ME199K mice, and "classical" PrP(Sc) as in infectious prion diseases, coincide in the patient's post mortem brains. We hypothesize that aberrant metabolism of mutant PrPs may result in the formation of previously unknown forms of the prion protein and that these may be central for the fatal outcome of the genetic prion condition.

PrP(ST, a soluble, protease resistant and truncated PrP form features in the pathogenesis of a genetic prion disease.

Directory of Open Access Journals (Sweden)

Yael Friedman-Levi

Full Text Available While the conversion of PrP(C into PrP(Sc in the transmissible form of prion disease requires a preexisting PrP(Sc seed, in genetic prion disease accumulation of disease related PrP could be associated with biochemical and metabolic modifications resulting from the designated PrP mutation. To investigate this possibility, we looked into the time related changes of PrP proteins in the brains of TgMHu2ME199K/wt mice, a line modeling for heterozygous genetic prion disease linked to the E200K PrP mutation. We found that while oligomeric entities of mutant E199KPrP exist at all ages, aggregates of wt PrP in the same brains presented only in advanced disease, indicating a late onset conversion process. We also show that most PK resistant PrP in TgMHu2ME199K mice is soluble and truncated (PrP(ST, a pathogenic form never before associated with prion disease. We next looked into brain samples from E200K patients and found that both PK resistant PrPs, PrP(ST as in TgMHu2ME199K mice, and "classical" PrP(Sc as in infectious prion diseases, coincide in the patient's post mortem brains. We hypothesize that aberrant metabolism of mutant PrPs may result in the formation of previously unknown forms of the prion protein and that these may be central for the fatal outcome of the genetic prion condition.

Upconversion excitations in Pr3+-doped BaY2F8 crystal

Science.gov (United States)

Piramidowicz, R.; Mahiou, R.; Boutinaud, P.; Malinowski, M.

2011-09-01

We report the orange-to-blue and infrared-(IR)-to-blue wavelengths upconversion luminescence in Pr3+:BaY2F8 crystals. Mechanism of the orange light upconversion into blue 3P0 state emission was confirmed to be energy transfer between two Pr3+ ions in the 1D2 state. IR-to-blue upconversion has only been observed under two different color IR pumping. The first resonant step was the 3H4→1G4 ground state absorption transition, and the second resonant transition was the excited state absorption from the 1G4 to 1I6 and 3PJ levels. A comparison of the efficiency of the IR-to-blue upconversion in several praseodymium activated host is presented and discussed. A model of the IR pumped upconversion praseodymium blue laser is presented and the population inversion conditions are calculated.

Preparation of Pr-doped SnO{sub 2} hollow nanofibers by electrospinning method and their gas sensing properties

Energy Technology Data Exchange (ETDEWEB)

Li, W.Q.; Ma, S.Y., E-mail: lwq19891013@126.com; Li, Y.F.; Li, X.B.; Wang, C.Y.; Yang, X.H.; Cheng, L.; Mao, Y.Z.; Luo, J.; Gengzang, D.J.; Wan, G.X.; Xu, X.L.

2014-08-25

Highlights: • Pr-doped SnO{sub 2} hollow nanofibers were fabricated by electrospinning. • The crystal structures, surface morphology, chemical state and gas sensing performance were investigated. • The Pr-doped SnO{sub 2} hollow structure exhibited good gas-sensing properties to ethanol at 300 °C. • The relationships between response time (recovery time) and temperature, response time (recovery time) and concentration were investigated. • A sensor mechanism of hollow nanofibers depend on temperature was discussed. - Abstract: Pure and Pr-doped SnO{sub 2} hollow nanofibers were fabricated through a facile single capillary electrospinning and followed by calcination. The properties of as-synthesized nanofibers were characterized by scanning electron microscopy, Brunauer–Emmett–Teller, transmission electron microscopy, X-ray diffraction and X-ray photoelectron spectroscopy. Compared with pure fibers, Pr-doped SnO{sub 2} nanofibers exhibited excellent ethanol sensing properties at the optimum temperature of 300 °C. Maximum sensing response to ethanol was received in the fibers with 0.6 wt% Pr. The relationships between response time (recovery time) and temperature, response time (recovery time) and concentration were investigated. The results demonstrated that the high response and relatively short response/recovery time were related to surface area, adsorbed oxygen species and oxygen vacancies.

Phonon dispersion relations in PrBa2Cu3O6+x (x approximate to 0.2)

DEFF Research Database (Denmark)

Gardiner, C.H.; Boothroyd, A.T.; Larsen, B.H.

2004-01-01

We report measurements of the phonon dispersion relations in nonsuperconducting, oxygen-deficient PrBa2Cu3O6+x (xapproximate to0.2) by inelastic neutron scattering. The data are compared with a model of the lattice dynamics based on a common interatomic potential. Good agreement is achieved for all...

Nuclear orientation of 9597Nb and 95Zr in ZrFe2

International Nuclear Information System (INIS)

Krane, K.S.; Olsen, C.E.; Rosenblum, S.S.; Steyert, W.A.

1976-01-01

The angular distribution anisotropies of γ rays were measured following the decays of 95 , 97 Nb and 95 Zr oriented at low temperatures in the ferromagnetic Laves phase compound ZrFe 2 . The magnetic hyperfine field of Nb in ZrFe 2 was deduced to be 9.4+-1.6 T; that of Zr in ZrFe 2 was estimated to be 15+-4 T. The nuclear magnetic moment of 97 Nb was deduced to be μ = (7.5+-1.4) μ/subN/

Breast Cancer Survival Defined by the ER/PR/HER2 Subtypes and a Surrogate Classification according to Tumor Grade and Immunohistochemical Bio markers

International Nuclear Information System (INIS)

Parise, C. A.; Caggiano, V.

2014-01-01

ER, PR, and HER2 are routinely available in breast cancer specimens. The purpose of this study is to contrast breast cancer-specific survival for the eight ER/PR/HER2 subtypes with survival of an immunohistochemical surrogate for the molecular subtype based on the ER/PR/HER2 subtypes and tumor grade. Methods. We identified 123,780 cases of stages 1-3 primary female invasive breast cancer from California Cancer Registry. The surrogate classification was derived using ER/PR/HER2 and tumor grade. Kaplan-Meier survival analysis and Cox proportional hazards modeling were used to assess differences in survival and risk of mortality for the ER/PR/HER2 subtypes and surrogate classification within each stage. Results. The luminal B/HER2− surrogate classification had a higher risk of mortality than the luminal B/HER2+ for all stages of disease. There was no difference in risk of mortality between the ER+/PR+/HER2− and ER+/PR+/HER2+ in stage 3. With one exception in stage 3, the ER-negative subtypes all had an increased risk of mortality when compared with the ER-positive subtypes. Conclusions. Assessment of survival using ER/PR/HER2 illustrates the heterogeneity of HER2+ subtypes. The surrogate classification provides clear separation in survival and adjusted mortality but underestimates the wide variability within the subtypes that make up the classification.

Structure, stability, and thermomechanical properties of Ca-substituted Pr2NiO4 + δ

Science.gov (United States)

Pikalova, E. Yu.; Medvedev, D. A.; Khasanov, A. F.

2017-04-01

Ca-substituted layered nickelates with a general Pr2- x Ca x NiO4 + δ composition ( x = 0-0.7, Δ x = 0.1) were prepared in the present work and their structural and physic-chemical properties were investigated in order to select the most optimal materials, which can be used as cathodes for solid oxide fuel cells. With an increase in Ca content in Pr2- x Ca x NiO4 + δ the following tendencies were observed: (i) a decrease in the concentration of nonstoichiometric oxygen (δ), (ii) a decrease in the unit cell parameters and volume, (iii) stabilization of the tetragonal structure, (iv) a decrease of the thermal expansion coefficients, and (v) enchancement of thermodynamic stability and compatibility with selected oxygen- and proton-conducting electrolytes. The Pr1.9Ca0.1NiO4 + δ material, having highest δ value, departs from the general "properties-composition" dependences ascertained. This indicates that oxygen non-stoichiometry has determining influence on the functional properties of layered nickelates.

PrPC displays an essential protective role from oxidative stress in an astrocyte cell line derived from PrPC knockout mice

International Nuclear Information System (INIS)

Bertuchi, Fernanda R.; Bourgeon, Dominique M.G.; Landemberger, Michele C.; Martins, Vilma R.; Cerchiaro, Giselle

2012-01-01

Highlights: ► PrP C in solution acts as a radical scavenger. ► PrP C reduces hydrogen peroxide toxicity in astrocytes. ► Increase in ROS disrupted the cell cycle in the PrP C -knockout astrocytes. ► PrP C prevents the cell death independently of an SOD-like activity. -- Abstract: The PrP C protein, which is especially present in the cellular membrane of nervous system cells, has been extensively studied for its controversial antioxidant activity. In this study, we elucidated the free radical scavenger activity of purified murine PrP C in solution and its participation as a cell protector in astrocytes that were subjected to treatment with an oxidant. In vitro and using an EPR spin-trapping technique, we observed that PrP C decreased the oxidation of the DMPO trap in a Fenton reaction system (Cu 2+ /ascorbate/H 2 O 2 ), which was demonstrated by approximately 70% less DMPO/OH · . In cultured PrP C -knockout astrocytes from mice, the absence of PrP C caused an increase in intracellular ROS (reactive oxygen species) generation during the first 3 h of H 2 O 2 treatment. This rapid increase in ROS disrupted the cell cycle in the PrP C -knockout astrocytes, which increased the population of cells in the sub-G1 phase when compared with cultured wild-type astrocytes. We conclude that PrP C in solution acts as a radical scavenger, and in astrocytes, it is essential for protection from oxidative stress caused by an external chemical agent, which is a likely condition in human neurodegenerative CNS disorders and pathological conditions such as ischemia.

Magnetic relaxation behaviour in Pr{sub 2}NiSi{sub 3}

Energy Technology Data Exchange (ETDEWEB)

Pakhira, Santanu, E-mail: santanupakhira20006@gmail.com; Mazumdar, Chandan; Ranganathan, R. [Condensed Matter Physics Division, Saha Institute Of Nuclear Physics, 1/AF Bidhannagar, Kolkata-700064 (India)

2016-05-06

Time dependent isothemal remanent magnetizatin (IRM) behaviour for polycrystalline compound Pr{sub 2}NiSi{sub 3} have been studied below its characteristic temperature. The compound undergoes slow magnetic relaxation with time. Along with competing interaction, non-magnetic atom disorder plays an important role in formation of non-equilibrium glassy like ground state for this compound.

Detail AR2-PR1 geochronological scale of the Baltic Shield

International Nuclear Information System (INIS)

Balashov, Yu.A.

1995-01-01

The version of the detail scale of the Precambrian Baltic Shield, based on selection of new crust increment through mantel genesis material is presented. The AR 2 -PR 1 -scale of the Baltic Shield is based through U-Pb, Rb-Sr and Sm-Nd-methods for the Cord Peninsula on the Precambrian period of the other Baltic Shield regions

Pseudospin model to describe transport properties in Bi2Sr2(CazPr1-z)Cu2O8+y

International Nuclear Information System (INIS)

Bastone, E.C.; Pires, A.S.T.; Silva, P.R.

2001-01-01

A pseudo-spin model is proposed, as a means to describe some transport properties (resistivity and Hall mobility) in Bi 2 Sr 2 (Ca z Pr 1-z )Cu 2 O 8+y . Our model is based in a double-well potential where tunneling in a given site and interaction between different lattice sites are allowed only through the excited states. Doping of the pure system by the addition of Pr increases the ratio between the activation energy and the tunneling constant. The model Hamiltonian displays some features which are present in the hydrogen-bonded ferroelectrics. Its dynamics is treated in the random phase approximation and the characteristic frequency (time) is used in a Drude formula in order to obtain some transport properties of the system, namely the electric resistivity and the Hall mobility. The quantities calculated in this work are compared with the experimental data given by Beschoten et al. (1996). (orig.)

Characterization of magnetic phase transitions in PrMn2Ge2 compound investigated by magnetization and hyperfine field measurements

Directory of Open Access Journals (Sweden)

B. Bosch-Santos

2017-05-01

Full Text Available The magnetic properties of PrMn2Ge2 compound have been investigated by perturbed γ−γ angular correlation (PAC spectroscopy using 111In(111Cd as probe nuclei as well as by magnetization measurements. This ternary intermetallic compound exhibits different magnetic structures depending on the temperature. The magnetic ordering is mainly associated with the magnetic moment of 3d-Mn sublattice but at low temperatures a magnetic contribution due to ordering of the magnetic moment from 4f-Pr sublattice appears. PAC results with 111Cd probe nuclei at Mn sites show that the temperature dependence of hyperfine field Bhf(T follows the expected behavior for the host magnetization, which could be fitted by two Brillouin functions, one for antiferromagnetic phase and the other for ferromagnetic phase, associated with the magnetic ordering of Mn ions. Magnetization measurements showed the magnetic behavior due to Mn ions highlighting the antiferromagnetic to ferromagnetic transition around 326 K and an increase in the magnetization around 36 K, which is ascribed to Pr ions ordering.

Magnetic properties of Pr ions in perovskite-type oxides

International Nuclear Information System (INIS)

Sekizawa, K.; Kitagawa, M.; Takano, Y.

1998-01-01

Magnetic properties of Pr ions with the controlled valence on the A and B sites of perovskite-type oxides (ABO 3 ) were investigated for two systems. PrSc 1-x Mg x O 3 and BaPr 1-x Bi x O 3 . From the magnetic susceptibility χ versus temperature T curves of PrSc 1-x Mg x O 3 , the χ-T curve for molar Pr 3+ ions on the A site and that of Pr 4+ ions were obtained. The 1/χ-T curves for both ions exhibit the crystalline electric field (CEF) effect and the effective magneticmoment μ eff above 100 K is 3.41 μ B for Pr 3- and 2.58 μ B for Pr 4+ , respectively. The χ-T curve of PrSc 0.8 Mg 0.2 O 3 is similar to that of PrBa 2 Cu 3 O y . In the BaPr 1-x Bi x O 3 system, only one intermediate phase BaPr 0.5 Bi 0.5 O 3 exists, in which Pr and Bi take an ordered arrangement on the B site. The magnetic susceptibility χ for Pr 4+ and that of Pr 3+ in the ordered arrangement with Bi 5- on the B site are much smaller than those for the A site, reflecting the strong CEF effect on the B site. Experimental χ-T curves can be well reproducedby the numerical calculation for Pr 3+ or Pr 4+ ions in the molecular field and the CEF with proper respective parameters. (orig.)

Thermodynamic database for the Co-Pr system

Directory of Open Access Journals (Sweden)

S.H. Zhou

2016-03-01

Full Text Available In this article, we describe data on (1 compositions for both as-cast and heat treated specimens were summarized in Table 1; (2 the determined enthalpy of mixing of liquid phase is listed in Table 2; (3 thermodynamic database of the Co-Pr system in TDB format for the research articled entitle Chemical partitioning for the Co-Pr system: First-principles, experiments and energetic calculations to investigate the hard magnetic phase W. Keywords: Thermodynamic database of Co-Pr, Solution calorimeter measurement, Phase diagram Co-Pr

Magnetic structure and physical properties of the multiferroic compound PrMn{sub 2}O{sub 5}

Energy Technology Data Exchange (ETDEWEB)

Doubrovsky, C. [Laboratoire de Physique des Solides, Universite Paris-Sud, CNRS-UMR 8502, 91405 Orsay Cedex (France); Andre, G. [Laboratoire Leon Brillouin, CEA-CNRS UMR 12, 91191 Gif-sur-Yvette Cedex (France); Bouquet, F. [Laboratoire de Physique des Solides, Universite Paris-Sud, CNRS-UMR 8502, 91405 Orsay Cedex (France); Elkaim, E. [Soleil Synchrotron, 91191 Gif-sur-Yvette Cedex (France); Li, M.; Greenblatt, M. [Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, Piscataway, NJ 08854 (United States); Foury-Leylekian, P., E-mail: pascale.foury@u-psud.fr [Laboratoire de Physique des Solides, Universite Paris-Sud, CNRS-UMR 8502, 91405 Orsay Cedex (France)

2012-06-01

RMn{sub 2}O{sub 5} (R=lanthanide, Bi, Y) multiferroic compounds are intensively studied for their potential application in the spintronic field. In these systems, the key issue is to understand the origin of the strong coupling between the ferroelectric and magnetic orders and to investigate the influence of the nature of the R ions in this coupling. While the phase diagram of RMn{sub 2}O{sub 5} compounds with small R size is well established, this of large R size compounds is missing due to the lack of samples originating with difficulties of synthesis. We present in this paper the first investigation of the thermodynamic, structural and magnetic properties of high quality polycrystalline PrMn{sub 2}O{sub 5} samples. Our work shows that PrMn{sub 2}O{sub 5} presents two magnetic transitions corresponding to commensurate magnetic orderings. We also evidence a weak lattice effect coupled to the magnetic order. Our results point out that the physical properties of PrMn{sub 2}O{sub 5} differ from those of the parent compounds with magnetic R ions.

Dependence of cross-relaxation on temperature and concentration from the 1D2 level of Pr3+ in YPO4

International Nuclear Information System (INIS)

Collins, John; Geen, Megan; Bettinelli, M.; Di Bartolo, B.

2012-01-01

We report on the role of cross-relaxation in the decay of the 1 D 2 level of trivalent Pr in YPO 4 in crystals with Pr concentrations of 0.1%, 1%, 2%, and 5%. We have found that the 1 D 2 level decay is purely radiative in the low-doped system. As the Pr concentration is increased, the 1 D 2 luminescence is quenched due to a cross-relaxation energy transfer between two Pr ions. The temporal behavior of the 1 D 2 luminescence following pulsed excitation has been monitored in each sample at temperatures between 30 K and 300 K, and all decay curves were fit to the Yokota–Tanimoto model. The decay times decrease as temperature increases, due to an increase in both the radiative rate and the energy transfer rate with temperature. There is little evidence of diffusion at any temperature, even in the more concentrated samples. We have also fit the decay curves using the LumiTrans computer simulation. A comparison of the fits to the decay curves of the two methods is presented. - Highlights: ► We present data on the decay of the 1 D 2 level of Pr in YPO 4 from 30–300 K. ► We determine the 1 D 2 cross-relaxation rate throughout that temperature range. ► Fits to the data indicate diffusion among the Pr ions is negligible. ► Radiative efficiencies of the 1 D 2 level are determined.

Production of no-carrier-added 139Pr via precursor decay in the proton bombardment of natPr

International Nuclear Information System (INIS)

Steyn, G.F.; Vermeulen, C.; Nortier, F.M.; Szelecsenyi, F.; Kovacs, Z.; Qaim, S.M.

2006-01-01

Excitation functions and production rates are presented for various Pr and Nd radionuclides formed in the bombardment of Pr with protons, from their respective thresholds up to 100 MeV. The indirect production route 141 Pr(p, 3n) 139m Nd → 139 Pr is investigated as an alternative to the direct production route 140 Ce(p, 2n) 139 Pr for producing no-carrier-added 139 Pr of high radionuclidic purity. The simultaneous production of 139 Pr and 140 Nd using Pr as target is investigated. The advantages and disadvantages of both production routes are discussed. Experimental thick-target production rates are presented for selected Pr radionuclides formed in the bombardment of nat Ce with protons at incident energies of 20, 26 and 32 MeV. All the experimental excitation functions obtained in this work are compared with theoretical predictions by means of the geometry-dependent hybrid (GDH) model as implemented in the code ALICE-IPPE. The results of this work are also compared with previous literature experimental data, if available

Laser operated elasto-optical features of La2CaB10O19:Pr3+ polymer nanocomposites

International Nuclear Information System (INIS)

Majchrowski, A.; Lakshminarayana, G.; Reshak, A.H.; Michalski, E.; Olifierczuk, M.; Ozga, K.; Jaroszewicz, L.; Lukasiewicz, T.; Szota, M.; Nabialek, M.

2012-01-01

We have discovered a principal role of the polymer matrices on the spectral dependences of piezooptical coefficients of La 2 CaB 10 O 19 :Pr 3+ (LCBO:Pr) nanocomposites formed by polymethylmethacrylate (PMMA) and polycarbonate (PC) matrices. It was established that the optical treatment by the 10 ns Nd:YAG laser can cause substantial changes of the dispersion of the piezooptical coefficients within the spectral wavelength 1400–1600 nm. The optimal content of the LCBO:Pr with sizes ranging from 40 to 110 nm corresponds to 4–6% in weighing units. Following the performed quantum chemical simulations, the observed changes are caused by different polarizabilities of the polymer matrices. - Highlights: ► Spectral dependences of piezooptical coefficients of La 2 CaB 10 O 19 :Pr 3+ nanocomposites were studied. ► Substantial enhancement of the piezooptical dispersion was observed within the spectral range 1440–1520 nm. ► The observed changes are caused by different polarizabilities of the polymer matrices.

Coupled magnetic excitations in single crystal PrBa₂Cu₃O_6.2

DEFF Research Database (Denmark)

Lister, S.J.S.; Boothroyd, A.T.; Andersen, N.H.

2001-01-01

The dispersion of the low-energy magnetic excitations of the Pr sublattice in PrBa2Cu3O6.2 is determined by inelastic neutron scattering measurements on a single crystal. The dispersion, which shows the effect of interactions with the Cu spin waves, is well described by a model of the coupled Cu...

Spectroscopy features of Pr{sup 3+} and Er{sup 3+} ions in Li{sub 2}O-ZrO{sub 2}-SiO{sub 2} glass matrices mixed with some sesquioxides

Energy Technology Data Exchange (ETDEWEB)

Srinivasa Rao, Ch. [Department of Physics, Acharya Nagarjuna University - Nuzvid Campus, Nuzvid-521201, A.P. (India); Kityk, I.V., E-mail: iwank74@gmail.com [Electrical Engineering Department, Technical University of Czestochowa, Aleja Armii, Krajowej 17/19, PL-42-201 Czestochowa (Poland); Srikumar, T.; Naga Raju, G.; Ravi Kumar, V.; Gandhi, Y.; Veeraiah, N. [Department of Physics, Acharya Nagarjuna University - Nuzvid Campus, Nuzvid-521201, A.P. (India)

2011-09-15

Highlights: > Optical spectra of Pr{sup 3+} and Er{sup 3+} ions in Li{sub 2}O-ZrO{sub 2}-SiO{sub 2}: Pr{sub 2}O{sub 3}/Er{sub 2}O{sub 3} with sesquioxides (viz., Al{sub 2}O{sub 3}, Sc{sub 2}O{sub 3}, Y{sub 2}O{sub 3}) studied. > The highest branching ratios {beta}{sub r} and quantum efficiencies of {sup 3}P{sub 0} {yields} {sup 3}H{sub 4} (Pr{sup 3+}) and {sup 4}S{sub 3/2} {yields} {sup 4}I{sub 15/2} (Er{sup 3+}) emissions have shown principal role of Y{sub 2}O{sub 3}. > Principal role of disorder around rare earth is established. - Abstract: The glasses of the composition Li{sub 2}O-ZrO{sub 2}-SiO{sub 2}: Pr{sub 2}O{sub 3}/Er{sub 2}O{sub 3} mixed with three interesting sesquioxides (viz., Al{sub 2}O{sub 3}, Sc{sub 2}O{sub 3}, Y{sub 2}O{sub 3}) were synthesized. Optical absorption and fluorescence spectra (in the spectral range 350-2100 nm were studied at ambient temperature. The Judd-Ofelt theory was applied to characterize the absorption and luminescence spectra of Pr{sup 3+} and Er{sup 3+} ions in these glasses. Following the luminescence spectra, various radiative properties like transition probability A, branching ratio {beta} and the radiative life time {tau} for different emission levels of two rare earth ions have been evaluated. The radiative life times for the upper levels {sup 3}P{sub 0} (Pr{sup 3+}) and {sup 4}S{sub 3/2} (Er{sup 3+}) have also been measured and quantum efficiencies were estimated. The variations observed in these parameters were discussed in the light of changing environment of rare earth ions due to mixing of different sesquioxides in the glass network.

Beyond PrPres type 1/Type 2 dichotomy in Creutzfeldt-Jakob disease

NARCIS (Netherlands)

Uro-Coste, E.; Cassard, H.; Simon, S.; Lugan, S.; Bilheude, J.M.; Perret-Liaudet, A.; Ironside, J.E.; Haik, S.; Basset-Leobon, C.; Lacroux, C.; Peoch, K.; Streichenberger, N.; Langeveld, J.P.M.; Head, M.W.; Grassi, J.; Hauw, J.J.; Schelcher, F.; Delisle, M.B.; Andreoletti, O.

2008-01-01

Sporadic Creutzfeldt-Jakob disease (sCJD) cases are currently subclassified according to the methionine/valine polymorphism at codon 129 of the PRNP gene and the proteinase K (PK) digested abnormal prion protein (PrPres) identified on Western blotting (type 1 or type 2). These biochemically distinct

Low-temperature thermal expansion measurements in PrV2Al20

International Nuclear Information System (INIS)

Magata, A.; Matsumoto, Y.; Tsujimoto, M.; Tomita, T.; Sakai, A.; Nakatsuji, S.; Kiichler, R.

2016-01-01

We have measured thermal expansion of PrV 2 Al 20 and LaV 2 Al 20 from room temperature down to 2 K, using a capacitance dilatometer. Linear thermal expansion ΔL/L along [111] direction decreases monotonically on cooling in both materials. The extracted 4ƒ electrons contribution of the linear thermal expansion coefficient a clearly shows a broad peak at ∼ 30 K which may correspond to the crystal electric field excited state at 40 K suggested in the previous specific heat study. (paper)

On the PR-algebras

International Nuclear Information System (INIS)

Lebedenko, V.M.

1978-01-01

The PR-algebras, i.e. the Lie algebras with commutation relations of [Hsub(i),Hsub(j)]=rsub(ij)Hsub(i)(i< j) type are investigated. On the basis of former results a criterion for the membership of 2-solvable Lie algebras to the PR-algebra class is given. The conditions imposed by the criterion are formulated in the linear algebra language

Controllable synthesis and tunable luminescence of glass ceramic containing Mn2+:ZnAl2O4 and Pr3+:YF3 nano-crystals

International Nuclear Information System (INIS)

Yu, Yunlong; Li, Xiaoyan

2016-01-01

Highlights: • Glass ceramic containing ZnAl 2 O 4 and YF 3 nano-crystals is fabricated. • Mn 2+ and Pr 3+ are selectively incorporated into ZnAl 2 O 4 and YF 3 , respectively. • The luminescence color can be tuned by adjusting the excitation wavelength. - Abstract: Glass ceramic containing spinel ZnAl 2 O 4 :Mn 2+ and orthorhombic YF 3 :Pr 3+ nano-crystals has been successfully prepared by a melt-quenching technique. X-ray diffraction and transmission electron microscopy demonstrated that two nano-phases, i.e. ZnAl 2 O 4 and YF 3 , were homogeneously distributed among the glass matrix. Importantly, the selective incorporation of Pr 3+ ions into the Y 3+ nine-fold coordinated sites of YF 3 and the segregation of Mn 2+ dopants in the Zn 2+ tetrahedral sites of ZnAl 2 O 4 were confirmed based on the excitation/emission spectra and the crystal field calculation. Under blue light excitation, both Pr 3+ and Mn 2+ in the glass ceramic can be simultaneously excited, and emit red and green luminescence, respectively, owing to the suppression of energy transfer between them. The luminescence color of the obtained glass ceramic can be easily tuned by adjusting the excitation wavelength. These results indicate the potential application of the glass ceramic as converting phosphor to generate white-light after coupling with the blue LED chip.

Investigation of structural imitation and lattice vibrations of Pr{sub 2}Fe{sub 17-} {sub x} Mn {sub x} compounds

Energy Technology Data Exchange (ETDEWEB)

Shen Jiang [Institute of Applied Physics, University of Science and Technology Beijing, 30 Xueyuou Road, HaiDian District, Beijing 100083 (China)]. E-mail: shenj@sas.ustb.edu.cn; Qian Ping [Institute of Applied Physics, University of Science and Technology Beijing, 30 Xueyuou Road, HaiDian District, Beijing 100083 (China); Chen Nanxian [Institute of Applied Physics, University of Science and Technology Beijing, 30 Xueyuou Road, HaiDian District, Beijing 100083 (China); Department of Physics, Tsinghua University, Beijing 100084 (China)

2005-03-15

We have investigated the structural properties of Pr{sub 2}Fe{sub 17-} {sub x} Mn {sub x} compounds by using quasi-ab initio pair potentials {phi} {sub Fe-Fe}(r), {phi} {sub Pr-Fe}(r), {phi} {sub Pr-Pr}(r), {phi} {sub Pr-Mn}(r), {phi} {sub Fe-Mn}(r) and {phi} {sub Mn-Mn}(r). In Pr{sub 2}Fe{sub 17-} {sub x} Mn {sub x} , the ternary elements Mn substitute for Fe atoms without changing the crystal structure. The calculated cohesive energy curves show that for all values of x, Mn preferentially substitutes for Fe in the 6c site and randomly substitutes for Fe in the 18f and 18h site. The calculated lattice constants coincide quite well with experimental values. Furthermore, the phonon density, specific heat and vibrational entropy of these compounds are also calculated. It is interesting that simple pair potentials can describe these extremely anisotropic materials.

Awareness of pre-exposure prophylaxis (PrEP) among women who inject drugs in NYC: the importance of networks and syringe exchange programs for HIV prevention.

Science.gov (United States)

Walters, Suzan M; Reilly, Kathleen H; Neaigus, Alan; Braunstein, Sarah

2017-06-29

Women who inject drugs (WWID) are at heightened risk for HIV due to biological, behavioral, and structural factors. Pre-exposure prophylaxis (PrEP) could aid in HIV prevention for WWID. However, little is known about WWID awareness of PrEP, which is a necessary step that must occur before PrEP uptake. We report factors associated with greater awareness among WWID to identify efficient means of awareness dissemination. Data from the 2015 National HIV Behavioral Surveillance (NHBS) system cycle on injection drug use collected in New York City (NYC) were used. Bivariable analyses, using chi-squared statistics, were conducted to examine correlates of awareness of PrEP with socio-demographic, behavioral, and health care variables. Multivariable logistic regression was used to estimate adjusted associations and determine differences in awareness of PrEP. The analysis consisted of 118 WWID. Awareness of PrEP was relatively low (31%), and risk factors were high. In the last 12 months, almost two thirds (65%) reported condomless sex, approximately one third (31%) reported transactional sex, and one third (32%) reported sharing injection equipment. In multivariable logistic regression, increased PrEP awareness was associated with reported transactional sex (AOR 3.32, 95% CI 1.22-9.00) and having a conversation about HIV prevention at a syringe exchange program (SEP) (AOR 7.61, 95% CI 2.65-21.84). We did not find race, education, household income, age, binge drinking, or sexual identity to be significantly associated with PrEP awareness. Large proportions of WWID were unaware of PrEP. These findings suggest that social networks (specifically sex work and SEP networks) are an efficient means for disseminating messaging about prevention materials such as PrEP. We recommend that SEP access increase, SEP processes be adopted in other health care settings, and WWID networks be utilized to increase PrEP awareness.

Study of absorption, emission and EDS properties of Pr3+ incorporated in a SiO2 matrix by sol-gel method

International Nuclear Information System (INIS)

Gómez-Miranda, M; Fonseca, R Sosa; Ordoñez, C Velásquez

2015-01-01

The optical response of the Pr 3+ ions doped monolith of SiO 2 prepared by sol-gel method was investigated by absorption and emission spectra. The absorption spectrum shows some typical lines of Pr 3+ , with these data was made the diagram levels corresponding to SiO 2 : Pr 3+ . The emission spectra were taken at 225 nm and 240 nm of wavelength of excitation was measured. In that there are reabsorption line at 423 of the Pr 3+ ions in the emission host, that means that some kind of host-ion interactions exist. Red and NIR emission at 612 nm, 652 nm, 711 and 728 nm, respectively, from Pr 3+ ions in SiO 2 was observed. The transition 1 S 0 → 3 P 2 at 425 nm is observed because an effective radiative transfer between the silicate glasses host and the praseodymium ions is observed and discussed

Novel synthetic route to molybdenum hydrido-thiocarbamoyl and hydrosulfido-carbyne complexes by reactions of trans-Mo(N{sub 2}){sub 2}(R{sub 2}PC{sub 2}H{sub 4}PR{sub 2}){sub 2} with N,N-dimethylthioformamide

Energy Technology Data Exchange (ETDEWEB)

Luo, X.L.; Kubas, G.J.; Burns, C.J.; Butcher, R.J. [Los Alamos National Lab., NM (United States)

1995-07-01

The reactions of bis(dinitrogen)molybdenum complexes trans-Mo(N{sub 2}){sub 2}(R{sub 2}PC{sub 2}H{sub 4}PR{sub 2}){sub 2} (R = Ph, Et) with N,N-dimethylthioformamide (HC(S)NMe{sub 2}) in refluxing benzene under argon give the molybdenum hydrido-thiocarbamoyl complexes MoH({eta}{sup 2}-C(S)NMe{sub 2})(R{sub 2}PC{sub 2}H{sub 4}PR{sub 2}){sub 2} (R = Ph (1a), Et (1b)). On heating at 125{degree}C in toluene solutions, compounds 1a and 1b rearrange to form the molybdenum hydrosulfido-aminocarbyne complexes trans-Mo(SH)-(=CNMe{sub 2})(R{sub 2}PC{sub 2}H{sub 4}PR{sub 2}){sub 2} (R = Ph (2a), Et (2b)). A mechanism is proposed for this thermal rearrangement which involves migration of the hydride ligand from molybdenum to the sulfur atom of the thiocarbamoyl ligand to give the 16-electron Fischer carbene intermediate Mo-(=C(SH)NMe{sub 2})(R{sub 2}PC{sub 2}H{sub 4}PR{sub 2}){sub 2}, followed by migration of the hydrosulfido group from the carbene carbon to molybdenum. The molecular structures of compounds 1a and 2a have been determined by single-crystal X-ray diffraction studies. 30 refs., 4 figs., 4 tabs.

Conventional and inverse magnetocaloric effect in Pr2CuSi3 and Gd2CuSi3 compounds

International Nuclear Information System (INIS)

Wang, Fang; Yuan, Feng-ying; Wang, Jin-zhi; Feng, Tang-fu; Hu, Guo-qi

2014-01-01

Highlights: • Two phase transitions in a narrow temperature range were observed and studied. • Both typical and inverse magnetocaloric effect were observed and discussed. • The inverse magnetocaloric effect was attributed to the spin-glass behavior. - Abstract: Magnetic properties and magnetocaloric effect (MCE) in Pr 2 CuSi 3 and Gd 2 CuSi 3 compounds were investigated systematically. Both Pr 2 CuSi 3 and Gd 2 CuSi 3 compounds experienced two phase transitions in a relatively narrow temperature range: first a paramagnet (PM)–ferromagnet (FM) second-order phase transition at 12 and 26 K and then a FM–spin glass (SG) transition at 6 K and 7.5 K, respectively. The magnetic entropy change (ΔS M ) was calculated based on Maxwell relation using the collected magnetization data. The maximum of ΔS M for Pr 2 CuSi 3 and Gd 2 CuSi 3 compounds was 7.6 and 5 J kg −1 K −1 , respectively, at the applied filed change of 0–5 T. The shape of the temperature dependence of ΔS M (ΔS M –T) curve was obviously different from that of the conventional magnetic materials undergoing only one typical phase transition. In the left half part of ΔS M –T curve, ΔS M is not very sensitive to the applied field and they tend to intersect with the decrease of temperature. Both typical conventional and inverse MCE behavior were observed in Gd 2 CuSi 3 , which would be originated from the two transition features at the low temperatures

Microwave properties of YBa2Cu3O7-δ/PrBa2Cu3O7-δ superlattices

International Nuclear Information System (INIS)

Carlos, W.E.; Kaplan, R.; Lowndes, D.H.; Norton, D.P.

1992-01-01

We have used non-resonant microwave absorption to study c-axis YBa 2 Cu 3 O 7-δ /PrBa 2 Cu 3 O 7-δ superlattices and compare the response to a film of similarly grown YBa 2 Cu 3 O 7-δ (YBCO). Near the respective transition temperatures, the response of the superlattice samples and the YBCO film have similar amplitudes and orientation dependences. This is consistent with the microwave loss being related to magnetic flux penetration at (110) slip planes. At lower temperatures, the response of the superlattices is much stronger than that of the YBCO film and, while both responses are hysteretic at low temperatures, the widths of the hysteresis have opposite orientation dependences, which we attribute to the role of the PrBa 2 Cu 3 O 7-δ layers. (orig.)

Aspects of Pr3+ luminescence in solids

International Nuclear Information System (INIS)

Srivastava, A.M.

2016-01-01

A brief perspective on the influence of “host lattice-Pr 3+ ” interactions on the optical properties of the Pr 3+ ion in solids is presented. How the energy position of the Pr 3+ 4f 1 5d 1 configuration relative to the 1 S 0 , 3 P J and host lattice conduction band levels influences the Pr 3+ optical properties is highlighted by considering solids in which the 4f 1 5d 1 configuration (1) is energetically above the 1 S 0 level, (2) is energetically below the 1 S 0 level, (3) is energetically close to the 1 S 0 level, and (4) overlaps with the host lattice conduction band. - Highlights: • Spectroscopic properties of Pr 3+ in solids is examined. • The influence of Pr 3+ 4f 1 5d 1 energy position relative to the 4f 2 levels is discussed. • The effect of interaction between Pr 3+ 4f 1 5d 1 and host conduction level is illustrated. • The paper identifies potential commercial applications.

Pr{sub 3}S{sub 2}Cl{sub 2}[AsS{sub 3}]: a praseodymium(III) sulfide chloride thioarsenate(III) with double chains of condensed [SPr{sub 4}]{sup 10+} tetrahedra

Energy Technology Data Exchange (ETDEWEB)

Kang, Dong-Hee [Institute for Inorganic Chemistry, University of Stuttgart (Germany); Department of Chemistry, University of Waterloo, ON (Canada); Korea Research Institute of Standards and Science (KRISS), Daejeon (Korea, Republic of); Ledderboge, Florian; Schleid, Thomas [Institute for Inorganic Chemistry, University of Stuttgart (Germany); Kleinke, Holger [Department of Chemistry, University of Waterloo, ON (Canada)

2015-02-15

Single crystals of Pr{sub 3}S{sub 2}Cl{sub 2}[AsS{sub 3}] were obtained by reacting praseodymium sesquisulfide and trichloride with arsenic and sulfur (molar ratio: 7:4:6:9) in torch-sealed evacuated silica ampoules at 850 C for a week and subsequent slow cooling to room temperature. The transparent, pale yellowish green platelets crystallize monoclinically (Pr{sub 3}S{sub 2}Cl{sub 2}[AsS{sub 3}]: a = 2190.96(9) pm, b = 685.49(3) pm, c = 701.87(3) pm, β = 98.752(3) ) in the non-centrosymmetric space group Cc with Z = 4. The crystal structure of Pr{sub 3}S{sub 2}Cl{sub 2}[AsS{sub 3}] comprises three crystallographically different Pr{sup 3+} cations. (Pr1){sup 3+} and (Pr2){sup 3+} exhibit bicapped trigonal prismatic environments of five sulfur and three chlorine atoms (C.N. = 8) each, whereas only seven sulfur atoms arranged as capped trigonal prism (C.N. = 7) are present in the case of (Pr3){sup 3+}. Two of the five crystallographically different sulfur atoms (S1 and S2) are coordinated by four Pr{sup 3+} cations, each in the shape of slightly distorted [SPr{sub 4}]{sup 10+} tetrahedra (d(S-Pr) = 278-294 pm). Hence, the crystal structure of Pr{sub 3}S{sub 2}Cl{sub 2}[AsS{sub 3}] contains double chains with the composition {sup 1}{sub ∞}{[S_2Pr_3]"5"+}, consisting of two parallel edge-fused chains of anti-SiS{sub 2}-analogous single strands {sup 1}{sub ∞}{[SPr_2]"4"+}, formed by trans-edge sharing [SPr{sub 4}]{sup 10+} tetrahedra. The arrangement of the {sup 1}{sub ∞}{[S_2Pr_3]"5"+} double chains running along [001] can be described as a hexagonal rod-packing. Chloride anions (Cl1 and Cl2) as well as the isolated, ψ{sup 1}-tetrahedral thioarsenate(III) groups [AsS{sub 3}]{sup 3-} (d(As-S) = 228-229 pm) consisting of three sulfur atoms (S3, S4, and S5) and an As{sup 3+} cation carrying a stereochemically active non-bonding electron pair take care of the three-dimensional interconnection and the charge balance of the {sup 1}{sub ∞}{[S_2Pr_3]"5"+} double

Satellite line mapping in Eu3+–Ce3+ and Pr3+–Ce3+ codoped Y2SiO5

International Nuclear Information System (INIS)

Serrano, D.; Karlsson, J.; Zheng, L.; Dong, Y.; Ferrier, A.; Goldner, P.; Walther, A.; Rippe, L.; Kröll, S.

2016-01-01

In this work we perform a high-resolution spectroscopic investigation of Eu 3+ –Ce 3+ and Pr 3+ –Ce 3+ codoped Y 2 SiO 5 crystals. Satellite line spectra were recorded at low temperatures around the Eu 3+ : 7 F 0 → 5 D 0 and the Pr 3+ : 3 H 4 → 1 D 2 transitions. It is observed that the incorporation of Ce 3+ as a codopant notably changes the Eu 3+ and Pr 3+ satellite line patterns. Satellite lines measured in singly doped Eu 3+ :Y 2 SiO 5 were found at the same spectral positions in Eu 3+ –Ce 3+ codoped crystals. These coincident lines were concluded to be due to pairs of Eu 3+ ions. Extra satellite lines appeared in the codoped crystals, which were assigned to Ce 3+ related structures such as Ce 3+ –Eu 3+ pairs. The analysis of the Pr 3+ satellite line spectra presents further challenges. Satellite lines associated to Pr 3+ pairs show weaker intensity, presumably due to the efficient quenching of the Pr 3+1 D 2 emission through cross-relaxation paths ( 1 D 2 → 1 G 4 ; 3 H 4 → 3 F 4 ). The investigation of the Eu 3+ and Pr 3+ satellite line patterns in Y 2 SiO 5 is particularly interesting for their exploitation in rare-earth based quantum computation schemes. - Highlights: • We recorded Eu and Pr satellite lines in Y 2 SiO 5 with and without Ce as a codopant. • The presence of Ce leads to the appearance of extra satellite lines in the spectra. • The satellite lines are associated to minor crystal sites such as ion pairs. • Less than 100 ion pairs were detected per satellite line. • The exploitation of the satellite line structure is proposed for quantum computing.

Temperature dependence of the magnetostriction in polycrystalline PrFe1.9 and TbFe2 alloys: Experiment and theory

International Nuclear Information System (INIS)

Tang, Y. M.; Chen, L. Y.; Huang, H. F.; Xia, W. B.; Zhang, S. Y.; Wei, J.; Tang, S. L.; Du, Y. W.; Zhang, L.

2014-01-01

A remarkable magnetostriction λ 111 as large as 6700 ppm was found at 70 K in PrFe 1.9 alloy. This value is even larger than the theoretical maximum of 5600 ppm estimated by the Steven's equivalent operator method. The temperature dependence of λ 111 for PrFe 1.9 and TbFe 2 alloys follows well with the single-ion theory rule, which yields giant estimated λ 111 values of about 8000 and 4200 ppm for PrFe 1.9 and TbFe 2 alloys, respectively, at 0 K. The easy magnetization direction of PrFe 1.9 changes from [111] to [100] as temperature decreases, which leads to the abnormal decrease of the magnetostriction λ. The rare earth sublattice moment increases sharply in PrFe 1.9 alloy with decreasing temperature, resulting in the remarkably largest estimated value of λ 111 at 0 K according to the single-ion theory

10 CFR 2.106 - Notice of issuance.

Science.gov (United States)

2010-01-01

... previously published. (d) The Director of Nuclear Material Safety and Safeguards will also cause to be... Application-How Initiated § 2.106 Notice of issuance. (a) The Director, Office of New Reactors, Director, Office of Nuclear Reactor Regulation, or Director, Office of Nuclear Material Safety and Safeguards, as...

Phosphorus and Cu2+ removal by periphytic biofilm stimulated by upconversion phosphors doped with Pr3+-Li.

Science.gov (United States)

Zhu, Yan; Zhang, Jianhong; Zhu, Ningyuan; Tang, Jun; Liu, Junzhuo; Sun, Pengfei; Wu, Yonghong; Wong, Po Keung

2018-01-01

Upconversion phosphors (UCPs) can convert visible light into luminescence, such as UV, which can regulate the growth of microbes. Based on these fundamentals, the community composition of periphytic biofilms stimulated by UCPs doped with Pr 3+ -Li + was proposed to augment the removal of phosphorus (P) and copper (Cu). Results showed that the biofilms with community composition optimized by UCPs doped with Pr 3+ -Li + had high P and Cu 2+ removal rates. This was partly due to overall bacterial and algal abundance and biomass increases. The synergistic actions of algal, bacterial biomass and carbon metabolic capacity in the Pr-Li stimulated biofilms facilitated the removal of P and Cu 2+ . The results show that the stimulation of periphytic biofilms by lanthanide-doped UCPs is a promising approach for augmenting P and Cu 2+ removal. Copyright © 2017 Elsevier Ltd. All rights reserved.

Luminescent properties and quenching effects of Pr3+ co-doping in SiO2:Tb3+/Eu3+ nanophosphors

CSIR Research Space (South Africa)

Mhlongo, GH

2014-02-01

Full Text Available Luminescence properties of Pr(sup3+) single doped SiO2 and Pr(sup3+) co-doped SiO(sub2):Tb(sup3+)/Eu(sup3+) nanophosphors synthesized using sol–gel method were investigated. X-ray diffraction (XRD), and scanning electron microscope (SEM) were used...

Relaxation of the electronic states at a thin-layer YBa2Cu 3O7/PrBa2Cu3O7 interface

KAUST Repository

Gó mez, Javier Alexandra M; Larkin, Ivan A.; Schwingenschlö gl, Udo

2010-01-01

We discuss in detail spin-polarized electronic structure calculations for the 1 × 1 YBa2Cu3O7/PrBa 2Cu3O7 superlattice. Our results are based on the full-potential linear augmented plane wave method and the generalized gradient approximation for the exchange-correlation functional. The on-site Coulomb interaction affecting the correlated Cu 3d and Pr 4f electrons is taken into consideration. At first glance the YBa2Cu3O 7/PrBa2Cu3O7 interface appears to be inert, i.e., the electronic states do not show a clear sign of interaction between the two component materials. Nonetheless, a total energy analysis points to a significant modification of the magnetic coupling in the vicinity of the interface due to the relaxation of the electronic structure. © 2010 Elsevier B.V. All rights reserved.

Relaxation of the electronic states at a thin-layer YBa2Cu 3O7/PrBa2Cu3O7 interface

KAUST Repository

Gómez, Javier Alexandra M

2010-11-01

We discuss in detail spin-polarized electronic structure calculations for the 1 × 1 YBa2Cu3O7/PrBa 2Cu3O7 superlattice. Our results are based on the full-potential linear augmented plane wave method and the generalized gradient approximation for the exchange-correlation functional. The on-site Coulomb interaction affecting the correlated Cu 3d and Pr 4f electrons is taken into consideration. At first glance the YBa2Cu3O 7/PrBa2Cu3O7 interface appears to be inert, i.e., the electronic states do not show a clear sign of interaction between the two component materials. Nonetheless, a total energy analysis points to a significant modification of the magnetic coupling in the vicinity of the interface due to the relaxation of the electronic structure. © 2010 Elsevier B.V. All rights reserved.

A novel Online-to-Offline (O2O) model for pre-exposure prophylaxis and HIV testing scale up.

Science.gov (United States)

Anand, Tarandeep; Nitpolprasert, Chattiya; Trachunthong, Deondara; Kerr, Stephen J; Janyam, Surang; Linjongrat, Danai; Hightow-Weidman, Lisa B; Phanuphak, Praphan; Ananworanich, Jintanat; Phanuphak, Nittaya

2017-03-13

PrEP awareness and uptake among men who have sex with men (MSM) and transgender women (TG) in Thailand remains low. Finding ways to increase HIV testing and PrEP uptake among high-risk groups is a critical priority. This study evaluates the effect of a novel Adam's Love Online-to-Offline (O2O) model on PrEP and HIV testing uptake among Thai MSM and TG and identifies factors associated with PrEP uptake. The O2O model was piloted by Adam's Love (www.adamslove.org) HIV educational and counselling website. MSM and TG reached online by PrEP promotions and interested in free PrEP and/or HIV testing services contacted Adam's Love online staff, received real-time PrEP eCounseling, and completed online bookings for receiving services at one of the four sites in Bangkok based on their preference. Auto-generated site- and service-specific e-tickets and Quick Response (QR) codes were sent to their mobile devices enabling monitoring and check-in by offline site staff. Service uptake and participant's socio-demographic and risk behaviour characteristics were analyzed. Factors associated with PrEP uptake were assessed using multiple logistic regression. Between January 10th and April 11th, 2016, Adam's Love reached 272,568 people online via the PrEP O2O promotions. 425 MSM and TG received eCounseling and e-tickets. There were 325 (76.5%) MSM and TG who checked-in at clinics and received HIV testing. Nine (2.8%) were diagnosed with HIV infection. Median (IQR) time between receiving the e-ticket and checking-in was 3 (0-7) days. Of 316 HIV-negative MSM and TG, 168 (53.2%) started PrEP. In a multivariate model, higher education (OR 2.30, 95%CI 1.14-4.66; p  = 0.02), seeking sex partners online (OR 2.05, 95%CI 1.19-3.54; p  = 0.009), being aware of sexual partners' HIV status (OR 2.37, 95%CI 1.29-4.35; p  = 0.008), ever previously using post-exposure prophylaxis (PEP) (OR 2.46, 95%CI 1.19-5.09; p  = 0.01), and enrolment at Adam's Love clinic compared to the other three sites

A phase I trial of PR-104, a pre-prodrug of the bioreductive prodrug PR-104A, given weekly to solid tumour patients

International Nuclear Information System (INIS)

McKeage, Mark J; Gu, Yongchuan; Wilson, William R; Hill, Andrew; Amies, Karen; Melink, Teresa J; Jameson, Michael B

2011-01-01

The phosphate ester PR-104 is rapidly converted in vivo to the alcohol PR-104A, a nitrogen mustard prodrug that is metabolised to hydroxylamine (PR-104H) and amine (PR-104M) DNA crosslinking agents by one-electron reductases in hypoxic cells and by aldo-keto reductase 1C3 independently of oxygen. In a previous phase I study using a q 3 week schedule of PR-104, the maximum tolerated dose (MTD) was 1100 mg/m 2 and fatigue, neutropenic fever and infection were dose-limiting. The primary objective of the current study was to determine the dose-limiting toxicity (DLT) and MTD of weekly PR-104. Patients with advanced solid tumours received PR-104 as a 1-hour intravenous infusion on days 1, 8 and 15 every 28 days with assessment of pharmacokinetics on cycle 1 day 1. Twenty-six patients (pts) were enrolled (16 male/10 female; median age 58 yrs, range 30 to 70 yrs) who had received a median of two prior chemotherapy regimens (range, 0 to 3) for melanoma (8 pts), colorectal or anal cancer (3 pts), NSCLC (3 pts), sarcoma (3 pts), glioblastoma (2 pts), salivary gland tumours (2 pts) or other solid tumours (5 pts). PR-104 was administered at 135 mg/m 2 (3 pts), 270 mg/m 2 (6 pts), 540 mg/m 2 (6 pts), 675 mg/m 2 (7 pts) and 900 mg/m 2 (4 pts) for a median of two treatment cycles (range, 1 to 7 cycles) and five infusions (range, 1 to 18) per patient. Dose-limiting toxicities (DLTs) during cycle one included grade four thrombocytopenia at 540 mg/m 2 (1 of 6 pts) and grade four thrombocytopenia and neutropenia at 900 mg/m 2 (2 of 4 pts). At an intermediate dose of 675 mg/m 2 , there were no DLTs among a total of seven patients given 12 treatment cycles but all experienced moderate to severe (grade 2 to 4) haematological toxicity. Thrombocytopenia was delayed in its onset and nadir, and its recovery was protracted and incomplete in many patients. There were no complete or partial tumour responses. PR-104-induced thrombocytopenia and neutropenia correlated with plasma AUC of PR-104

1D and 2D assembly structures by imidazole···chloride hydrogen bonds of iron(II) complexes [Fe(II)(HL(n-Pr))3]Cl·Y (HL(n-Pr) = 2-methylimidazol-4-yl-methylideneamino-n-propyl; Y = AsF6, BF4) and their spin states.

Science.gov (United States)

Fujinami, Takeshi; Nishi, Koshiro; Matsumoto, Naohide; Iijima, Seiichiro; Halcrow, Malcolm A; Sunatsuki, Yukinari; Kojima, Masaaki

2011-12-07

Two Fe(II) complexes fac-[Fe(II)(HL(n-Pr))(3)]Cl·Y (Y = AsF(6) (1) and BF(4) (2)) were synthesized, where HL(n-Pr) is 2-methylimidazole-4-yl-methylideneamino-n-propyl. Each complex-cation has the same octahedral N(6) geometry coordinated by three bidentate ligands and assumes facial-isomerism, fac-[Fe(II)(HL(n-Pr))(3)](2+) with Δ- and Λ-enantiomorphs. Three imidazole groups per Δ- or Λ-fac-[Fe(II)(HL(n-Pr))(3)](2+) are hydrogen-bonded to three Cl(-) ions or, from the viewpoint of the Cl(-) ion, one Cl(-) ion is hydrogen-bonded to three neighbouring fac-[Fe(II)(HL(n-Pr))(3)](2+) cations. The 3 : 3 NH···Cl(-) hydrogen bonds between Δ- or Λ-fac-[Fe(II)(HL(n-Pr))(3)](2+) and Cl(-) generate two kinds of assembly structures. The directions of the 3 : 3 NH···Cl(-) hydrogen bonds and hence the resulting assembly structures are determined by the size of the anion Y, though Y is not involved into the network structure and just accommodated in the cavity. Compound 1 has a 1D ladder structure giving a larger cavity, in which the Δ- and Λ-fac-[Fe(II)(HL(n-Pr))(3)](2+) enantiomorphs are bridged by two NH···Cl(-) hydrogen bonds. Compound 2 has a 2D network structure with a net unit of a cyclic trimer of {fac-[Fe(II)(HL(n-Pr))(3)](2+)···Cl(-)}(3) giving a smaller cavity, in which Δ- or Λ-fac-[Fe(II)(HL(n-Pr))(3)](2+) species with the same chirality are linked by NH···Cl(-) hydrogen bonds to give a homochiral 2D network structure. Magnetic susceptibility and Mössbauer spectral measurements demonstrated that compound 1 showed an abrupt one-step spin crossover with 4.0 K thermal hysteresis of T(c↓) = 125.5 K and T(c↑) = 129.5 K and compound 2 showed no spin transition and stayed in the high-spin state over the 5-300 K temperature range.

Magnetic ordering in single crystals of PrBa sub 2 Cu sub 3 O sub 7 sub - subdelta

CERN Document Server

Uma, S; Gmelin, E; Rangarajan, G; Skanthakumar, S; Lynn, J W; Walter, R; Lorenz, T; Büchner, B; Walker, E; Erb, A

1998-01-01

Heat capacity measurements on pure but twinned single crystals of PrBa sub 2 Cu sub 3 O sub 7 sub - subdelta reveal a sharp peak at T sub N sup P sup sub T =16.6 K, which according to thermal expansion, neutron diffraction, and magnetic susceptibility measurements originates from an antiferromagnetic ordering of the Pr-ion moments. A modest coupling to the Cu(2) spin system is observed. Below T sub N sup P sup sub T a first-order transition in the magnetic structure of the Pr spin system (at 13.4 K in warming; approx. 11 K in cooling) is found. Field-dependent heat capacity data show anisotropic temperature dependences of the c sub p -peaks and recover a Schottky-like anomaly due to the crystal-field-split ground state of the Pr sup 3 sup +. (author). Letter-to-the-editor

Phonon dispersion relations in PrBa2Cu3O6+x (x≅0.2)

International Nuclear Information System (INIS)

Gardiner, C.H.; Boothroyd, A.T.; Larsen, B.H.; Reichardt, W.; Zhokhov, A.A.; Andersen, N.H.; Lister, S.J.S.; Wildes, A.R.

2004-01-01

We report measurements of the phonon dispersion relations in nonsuperconducting, oxygen-deficient PrBa 2 Cu 3 O 6+x (x≅0.2) by inelastic neutron scattering. The data are compared with a model of the lattice dynamics based on a common interatomic potential. Good agreement is achieved for all but two phonon branches, which are significantly softer than predicted. These modes are found to arise predominantly from motion of the oxygen ions in the CuO 2 planes. Analogous modes in YBa 2 Cu 3 O 6 are well described by the common interatomic potential model

On PR group classes and PR algebra membership

International Nuclear Information System (INIS)

Lebedenko, V.M.

1978-01-01

The necessary and sufficient conditions are found for the membership of Lee algebras to PR algebra class, to algebras with commutation relations of [Hsub(i), Hsub(j)]=rsub(ij)Hsub(i) (i< j) type. Due to this, a criterion is obtained for the membership of the Lee froups to PR group classes, connected and simply connected Lee groups, which Lee algebras are PR algebras

Anisotropic Transport and Magnetic Properties of Charge-Density-Wave Materials RSeTe_2 (R = La, Ce, Pr, Nd)

International Nuclear Information System (INIS)

Wang Pei-Pei; Long Yu-Jia; Zhao Ling-Xiao; Chen Dong; Xue Mian-Qi; Chen Gen-Fu

2015-01-01

Single crystals of RSeTe_2 (R = La, Ce, Pr, Nd) are synthesized using LiCl/RbCl flux. Transport and magnetic properties in the directions parallel and perpendicular to the a–c plane are investigated. We find that the resistivity anisotropy ρ_⊥/ρ_‖ lies in the range 486–615 for different compounds at 2 K, indicating the highly two-dimensional character. In both the orientations, the charge-density-wave transitions start near T_C_D_W = 284(3) K, 316(3) K, 359(3) K for NdSeTe_2, PrSeTe_2, CeSeTe_2, respectively, with a considerable increase in dc resistivity. While for LaSeTe_2, no obvious resistivity anomaly is observed up to 380 K. The value of T_C_D_W increases monotonically with the increasing lattice parameters. Below T_C_D_W, slight anomalies can be observed in NdSeTe_2, PrSeTe_2 and CeSeTe_2 with onset temperature at 193(3) K, 161(3) K, 108(3) K, respectively, decreasing as lattice parameters increase. Magnetic susceptibility measurements show that the valence state of rare earth ions are trivalence in these compounds. Antiferromagnetic-type magnetic order is formed in CeSeTe_2 at 2.1 K, while no magnetic transition is observed in PrSeTe_2 and NdSeTe_2 down to 1.8 K. (paper)

Relationship between electrical and structural properties in Pr2/3+xTiO3±y

International Nuclear Information System (INIS)

Kirsanov, N.A.; Bazuev, G.V.

1987-01-01

Synthesis conditions results of X-ray diffraction investigations and electric properties of oxide titanium bronzes (OTB) of praseodymium Pr 2/3+x TiO 3±y in homogeneity region are presented. Change of crystal lattice symmetry in the region of existence of oxide titanium bronzes Pr 2/3+x TiO 3 ± y (O ≤ x ≤ 1/3) was revealed. Specific electrical resistance measurements enabled to conclude that d-electrons of Ti 3+ cations were characterized by collectivized behaviour, conditioned by formation of harrow, partially occupied π*-zone

Comparative study of electronic structure and charge transport in isostructural cuprates YBa2Cu3O7 and PrBa2Cu3O7

International Nuclear Information System (INIS)

Kormilets, V.I.

1997-01-01

The self-consistent calculations of electronic structure and charge distribution in YBa 2 Cu 3 O 7 and PrBa 2 Cu 3 O 7 crystals were performed by the method of linear muffin-tin orbitals with full potentials (FP-LMTO). It is revealed that the substitution of Pr for Y results in the charge transfer from a CuO chain to a CuO 2 plane. In its turn, this results in partial innihilation of holes responsible for superconductivity. The effect is analogous to that arisen from the removal of oxygen atoms from CuO chains. It is shown that the degree of covalence of 1-2-3 compounds being considered constitutes and essential value and decreases with pr substitution for Y

Study of PrP - I heterogeneous equilibrium

International Nuclear Information System (INIS)

Vasil'eva, I.G.; Mironov, K.E.; Tarasenko, A.D.

1976-01-01

Using static methods the authors have measured the equilibrium vapor pressure in the system PrP+I 2 at different temperatures and different initial iodine concentrations. The equilibrium reactions in the system have been determined. The reaction of PrP with iodine is irreversible. The content of PrI 3 and I 2 in the gas phase is negligible. The pressure in the system is determined by the partial pressure of phosphorus

Spectroscopic and radiation-resistant properties of Er,Pr:GYSGG laser crystal operated at 2.79 μm

International Nuclear Information System (INIS)

Zhao Xu-Yao; Sun Dun-Lu; Luo Jian-Qiao; Zhang Hui-Li; Fang Zhong-Qing; Quan Cong; Li Xiu-Li; Cheng Mao-Jie; Zhang Qing-Li; Yin Shao-Tang

2017-01-01

We demonstrate the spectroscopic and laser performance before and after 100 Mrad gamma-ray irradiation on an Er,Pr:GYSGG crystal grown by the Czochralski method. The additional absorption of Er,Pr:GYSGG crystal is close to zero in the 968 nm pumping and 2.7–3 μm laser wavelength regions. The lifetimes of the upper and lower levels show faint decreases after gamma-ray irradiation. The maximum output powers of 542 and 526 mW with the slope efficiencies of 17.7% and 17.0% are obtained, respectively, on the GYSGG/Er,Pr:GYSGG composite crystal before and after the gamma-ray irradiation. These results suggest that Er,Pr:GYSGG crystal as a laser gain medium possesses a distinguished anti-radiation ability for application in space and radiant environments. (paper)

Use of ER/PR/HER2 subtypes in conjunction with the 2007 St Gallen Consensus Statement for early breast cancer

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Parise Carol

2010-05-01

Full Text Available Abstract Background The 2007 St Gallen international expert consensus statement describes three risk categories and provides recommendations for treatment of early breast cancer. The set of recommendations on how to best treat primary breast cancer is recognized and used by clinicians worldwide. We now examine the variability of five-year survival of the 2007 St Gallen Risk Classifications utilizing the ER/PR/HER2 subtypes. Methods Using the population-based California Cancer Registry, 114,786 incident cases of Stages 1-3 invasive breast cancer diagnosed between 2000 and 2006 were identified. Cases were assigned to Low, Intermediate, or High Risk categories. Five-year-relative survival was computed for the three St Gallen risk categories and for the ER/PR/HER2 subtypes for further differentiation. Results and Discussion There were 9,124 (13% cases classified as Low Risk, 44,234 (65% cases as Intermediate Risk, and 14,340 (21% as High Risk. Within the Intermediate Risk group, 33,735 (76% were node-negative (Intermediate Risk 2 and 10,499 (24% were node-positive (Intermediate Risk 3. For the High Risk group, 6,149 (43% had 1 to 3 positive axillary lymph nodes (High Risk 4 and 8,191 (57% had four or more positive lymph nodes (High Risk 5. Using five-year relative survival as the principal criterion, we found the following: a There was very little difference between the Low Risk and Intermediate Risk categories; b Use of the ER/PR/HER2 subtypes within the Intermediate and High Risk categories separated each into a group with better five-year survival (ER-positive and a group with worse survival (ER-negative, irrespective of HER2-status; c The heterogeneity of the High Risk category was most evident when one examined the ER/PR/HER2 subtypes with four or more positive axillary lymph nodes; (d HER2-positivity did not always translate to worse survival, as noted when one compared the triple positive subtype (ER+/PR+/HER2+ to the triple negative subtype

Synthesis and characterization of environmentally benign calcium-doped Pr2Mo2O9 pigments: Applications in coloring of plastics

International Nuclear Information System (INIS)

George, Giable; Sandhya Kumari, L.; Vishnu, V.S.; Ananthakumar, S.; Reddy, M.L.P.

2008-01-01

A new class of environmentally benign rare earth pigments of general formula Pr 2-x Ca x Mo 2 O 9-δ (x ranges from 0 to 1.0) displaying colors ranging from green to yellow were synthesized by traditional solid-state route, as alternatives to lead, cadmium and chromium colorants. The products were characterized by X-ray powder diffraction, UV-vis spectroscopy and CIE-L*a*b* 1976 color scales. The coloring mechanism is based on the strong absorptions of the pigments in the blue and red regions due to electronic transitions between 4f 2 →4f 1 5d 1 states of Pr 3+ . The designed pigments consist of non-toxic elements and further found to be thermally and chemically stable. The yellow-green pigments were found to be interesting alternatives to existing toxic pigments for coloration of plastics. - Graphical abstract: A new class of environmentally benign rare earth pigments of general formula Pr 2-x Ca x Mo 2 O 9-δ (x ranges from 0 to 1.0) displaying colors ranging from green to yellow were synthesized by traditional solid-state route, as alternatives to lead, cadmium and chromium colorants. The yellow-green pigments were found to be interesting alternatives to existing toxic pigments for coloration of plastics. Display Omitted

Oxygen Nonstoichiometry and Defect Chemistry Modeling of Ce0.8Pr0.2O2-delta

OpenAIRE

Chatzichristodoulou, Christodoulos; Hendriksen, Peter Vang

2010-01-01

The oxygen nonstoichiometry (delta) of Ce0.8Pr0.2O2−delta has been measured as a function of PO2 at temperatures between 600 and 900°C by coulometric titration and thermogravimetry. An ideal solution defect model, a regular solution model, and a defect association model, taking into account the association of reduced dopant species and oxygen vacancies, were unable to reproduce the experimental results. However, excellent agreement with the experimentally determined oxygen nonstoichiometry co...

Synthesis, stability range and characterization of Pr2Cu2O5

Science.gov (United States)

Fernández-Sanjulián, Javier; Morán, Emilio; Ángel Alario-Franco, Miguel

2010-03-01

A novel Pr2Cu2O5 phase has been prepared under high-pressure and high-temperature conditions (P ∼6 GPa and T ∼1673 K) in a Belt-type apparatus and characterized by X-ray diffraction and electron microscopy. The crystal structure appears to be an orthorhombic "oxygen-deficient perovskite" (M.T. Anderson, J.T. Vaughey, and K.R. Poeppelmeier, Structural similarities among oxygen-deficient perovskites, Chem. Mater. 5 (1993), pp. 151-165) isostructural with La2Cu2O5 (J.F. Bringley, B.A. Scott, S.J. La Placa, R.F. Boheme, T.M. Shaw, M.W. McElfresh, S.S. Trail, and D.E. Cox, Synthesis of the defect perovskite series LaCuO 3-δ with copper valence varying from 2+to 3+, Nature 347 (1990), pp. 263-265) and Nd2Cu2O5 (B.-H. Chen, D. Walker, E. Suard, B.A. Scott, B. Mercey, M. Hervieu, and B. Raveau, High pressure synthesis of NdCuO3-δ perovskites (0≤δ≤0.5). Inorg. Chem. 34 (1995), pp. 2077-2083).

Neutron Scattering from fcc Pr and Pr3Tl

DEFF Research Database (Denmark)

Birgeneau, R. J.; Als-Nielsen, Jens Aage; Bucher, E.

1972-01-01

Elastic-neutron-scattering measurements on the singlet-ground-state ferromagnets fcc Pr and Pr3 Tl are reported. Both exhibit magnetic phase transitions, possibly to a simple ferromagnetic state at 20 and 11.6 °K, respectively. The transitions appear to be of second order although that in fcc Pr...

Magnetic ordering in PrBa2Cu3-yAlyO6+x

DEFF Research Database (Denmark)

Longmore, A.; Boothroyd, A.T.; Chen, C.K.

1996-01-01

The magnetic ordering in single crystals of PrBa2CU3O6+x has been investigated by elastic neutron scattering over the full range of temperatures for reduced and oxygenated crystals. The crystals were grown in alumina crucibles and therefore contained dissolved aluminum on the Cu(1) site. Both...... aluminum and oxygen contents were analyzed in detail in order to establish their effects on the magnetic ordering, Our crystals exhibited Pr ordering and the two types of antiferromagnetic Cu ordering frequently reported in related compounds, but our results differ in several respects from previous studies...... axis, we find the moment to be aligned well away from the c axis, in agreement with recent Yb-170(3+) Mossbauer spectroscopy results. Ridges of scattering indicative of 2D magnetic ordering were seen in both oxygenated and reduced crystals, though we believe different magnetic moments are responsible...

Enhanced ~2.7 µm emission investigation of Er{sup 3+}:{sup 4}I{sub 11/2}→{sup 4}I{sub 13/2} transition in Yb,Er,Pr:SrLaGa{sub 3}O{sub 7} crystal

Energy Technology Data Exchange (ETDEWEB)

Wang, Yan [Key Laboratory of Optoelectronic Materials Chemistry and Physics, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002 (China); Zhang, Baotong [Key Laboratory of Optoelectronic Materials Chemistry and Physics, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002 (China); College of Materials Science and Engineering, Fujian Normal University, Fuzhou, Fujian 350007 (China); Li, Jianfu; Zhu, Zhaojie; You, Zhenyu [Key Laboratory of Optoelectronic Materials Chemistry and Physics, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002 (China); Tu, Chaoyang, E-mail: tcy@fjirsm.ac.cn [Key Laboratory of Optoelectronic Materials Chemistry and Physics, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002 (China)

2017-03-15

The bulk crystal of 5at% Yb{sup 3+}, 20 at% Er{sup 3+} and 0.2 at% Pr{sup 3+} triply doped SrLaGa{sub 3}O{sub 7} (abbr. as Yb,Er,Pr:SLGO) was grown by the Czochralski method. The effects of co-dopant Yb{sup 3+} and Pr{sup 3+} on the spectroscopic properties and the mutual energy transfer mechanism were investigated, via the measurements of its absorption, near-infrared and mid-infrared fluorescence spectra, as well as the fluorescence decay curves of Er{sup 3+}:{sup 4}I{sub 13/2} and {sup 4}I{sub 11/2} levels at room temperature. As compared with 20at% Er{sup 3+} singly doped SrLaGa{sub 3}O{sub 7} crystal, ~2.7 µm emission intensity corresponding to Er{sup 3+}:{sup 4}I{sub 11/2}→{sup 4}I{sub 13/2} transition is enhanced greatly in the Yb,Er,Pr:SLGO crystal. Spectral analyses indicate that the sensitization of Yb{sup 3+} to Er{sup 3+} improves the ~2.7 µm emission in Yb,Er,Pr:SLGO crystal, meanwhile, the depopulation of Pr{sup 3+} from Er{sup 3+} decreases the ~1.5 µm emission and inhibits the self-termination effect. The energy transfer efficiencies of Yb{sup 3+}→Er{sup 3+} (ET1), Er{sup 3+}→Pr{sup 3+} (ET2) and Er{sup 3+}→Pr{sup 3+} (ET3) were estimated and discussed. The above results conclude that Yb,Er,Pr:SLGO crystal is a good candidate for LD pumped mid-infrared laser. - Graphical abstract: As compared with Er: SrLaGa{sub 3}O{sub 7} crystal, ~2.7 µm MIR emissions corresponding to Er{sup 3+}:{sup 4}I{sub 11/2}→{sup 4}I{sub 13/2} transition were enhanced in Yb{sup 3+}, Er{sup 3+} and Pr{sup 3+} triply doped SrLaGa{sub 3}O{sub 7} crystal owing to the sensitization of co-dopant Yb{sup 3+} via ET1, at the same time, ~1.5 µm NIR emissions were weakened owing to the depopulation of co-dopant Pr{sup 3+} via ET3.

Uptake of PrEP and condom and sexual risk behavior among MSM during the ANRS IPERGAY trial.

Science.gov (United States)

Sagaon-Teyssier, Luis; Suzan-Monti, Marie; Demoulin, Baptiste; Capitant, Catherine; Lorente, Nicolas; Préau, Marie; Mora, Marion; Rojas Castro, Daniela; Chidiac, Christian; Chas, Julie; Meyer, Laurence; Molina, Jean-Michel; Spire, Bruno

2016-01-01

The double-blind phase of the randomized ANRS IPERGAY trial, evaluating sexual activity-based oral HIV pre-exposure prophylaxis (PrEP), was conducted among high-risk men who have sex with men (MSM). Results showed an 86% (95% CI: 40-98) relative reduction in HIV incidence among participants with tenofovir disoproxil fumarate-emtricitabine vs. placebo. The present pooled analysis aimed to analyze (i) participants' adherence to the prescribed treatment and/or condom use during sexual intercourse and (ii) sexual behavior during the double-blind phase of the study. Four hundred MSM were enrolled in the trial. Every 2 months they completed online questionnaires collecting sexual behavior and PrEP adherence data regarding their most recent sexual intercourse. A total of 2232 questionnaires (M0-M24) were analyzed. Changes over time were evaluated using a mixed model accounting for multiple measures. Irrespective of sexual partner and practice type, on average, 42.6% (min: 32.1-max: 45.8%) reported PrEP use only during their most recent episode of sexual intercourse; 29% (22.9-35.6%) reported both PrEP and condom use; 11.7% (7.2-18.9%) reported condom-use only, and 16.7% (10.8-29.6%) reported no PrEP or condom use with no significant change during the study. Scheduled (i.e., correct) PrEP use was reported on average by 59.0% (47.2-68.5%) of those reporting PrEP use during their most recent sexual intercourse. Overall, 70.3% (65.3-79.4%) and 69.3% (58.3-75.4%) of participants reported, respectively, condomless anal and condomless receptive anal intercourse during their most recent sexual encounter without significant change during follow-up. Overall, on average 83.3% (min: 70.4-max: 89.2%) of participants protected themselves by PrEP intake or condom use or both during the trial, and no increase in at-risk sexual practices was observed. None of these indicators showed significant trend during the follow-up, although we found a tendency toward decrease (p = .19) of the

Moessbauer studies of single crystal Pr sub 1 sub / sub 3 Sr sub 2 sub / sub 3 FeO sub 3

CERN Document Server

Uhm, Y R; Kim, C S; Tomioka, Y; Tokura, Y

2000-01-01

Single crystal Pr sub 1 sub / sub 3 Sr sub 2 sub / sub 3 FeO sub 3 was synthesized by using the floating zone method and the relation of magnetic properties and charge ordering transition with lattice dynamics was systematically investigated. Moessbauer spectra of Pr sub 1 sub / sub 3 sub S r sub 2 sub / sub 3 FeO sub 3 were taken at various temperatures ranging from 20 K to room temperature. The charge disproportionation, in which iron with valence states Fe sup 3 sup + and Fe sup 5 sup + was found in a ratio of 2:1, was detected in Pr sub 1 sub / sub 3 Sr sub 2 sub / sub 3 FeO sub 3 below 190+-3 K. Iron with valence state Fe sup 4 sup + coexisted in Pr sub 1 sub / sub 3 sub S r sub 2 sub / sub 3 FeO sub 3 at and above 150 K, and its ratio increased from 13 to 66 % with increasing temperature. This result means that charge-ordered and -disordered phases co-exist in Pr sub 1 sub / sub 3 Sr sub 2 sub / sub 3 FeO sub 3.

Evidence for a central role of PrP helix 2 in the nucleation of amyloid fibrils.