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Sample records for srlnino4 ln-la pr

  1. Structures, magnetic, and thermal properties of Ln3MoO7 (Ln=La, Pr, Nd, Sm, and Eu)

    International Nuclear Information System (INIS)

    Nishimine, Hiroaki; Wakeshima, Makoto; Hinatsu, Yukio

    2005-01-01

    Ternary lanthanide-molybdenum oxides Ln 3 MoO 7 (Ln=La, Pr, Nd, Sm, Eu) have been prepared. Their structures were determined by X-ray diffraction measurements. They crystallize in a superstructure of cubic fluorite and the space group is P2 1 2 1 2 1 . The Mo ion is octahedrally coordinated by six oxygens and the slightly distorted octahedra share corners forming a zig-zag chain parallel to the b-axis. These compounds have been characterized by magnetic susceptibility and specific heat measurements. The La 3 MoO 7 shows complex magnetic behavior at 150 and 380K. Below these temperatures, there is a large difference in the temperature-dependence of the magnetic susceptibility measured under zero-field-cooled condition and under field-cooled condition. The Nd 3 MoO 7 show a clear antiferromagnetic transition at 2.5K. From the susceptibility measurements, both Pr 3 MoO 7 and Sm 3 MoO 7 show the existence of magnetic anomaly at 8.0 and 2.5K, respectively. The results of the specific heat measurements also show anomalies at the corresponding magnetic transition temperatures. The differential scanning calorimetry measurements indicate that two phase-transitions occur for any Ln 3 MoO 7 compound in the temperature range between 370 and 710K

  2. Magnetic properties of the layered oxypnictides (LnOMnAs (Ln = La, Ce, Pr, Nd

    Directory of Open Access Journals (Sweden)

    Morosawa Y.

    2014-07-01

    Full Text Available We have investigated the rare earth elements dependence on the magnetism to understand the contribution to physical properties of the 4f electrons of (LnOMnAs (Pn = La, Ce, Pr, Nd. (CeOMnAs, (PrOMnAs and (NdOMnAs shows the antiferromagnetic behaviors at low temperature. (CeOMnAs and (NdOMnAs have the magnetic anomalies around 34 K and 24 K, respectively. So, it is speculated that the anomalies depend on the Mn -Mn distance directly

  3. Magnetic properties of layered oxysulfide (LnO)CuS:Ln = La, Pr, Nd

    International Nuclear Information System (INIS)

    Nakao, H.; Takano, Y.; Takase, K.; Sato, K.; Hara, S.; Ikeda, S.; Takahashi, Y.; Sekizawa, K.

    2006-01-01

    We have prepared rare earth oxysulfides (PrO)CuS and (NdO)CuS in order to introduce magnetic moments into the non-magnetic p-type semiconductor (LaO)CuS. Both compounds are semiconductors with high electrical resistivity, and show the paramagnetic behavior. The temperature dependence of the magnetic susceptibility is well explained by the trivalent rare earth ion. However, it deviates from simple Curie Wiess law below 100 K due to the crystal field effect on rare earth ions. We have succeeded to reproduce their magnetic properties by the calculation taking the crystal field effect into account using the operator equivalent method

  4. 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.

  5. Crystal structure and phase transition studies in perovskite-type oxides using powder-diffraction techniques and symmetry-mode analysis : SrLnMRuO6 (Ln=La,Pr,Nd; M=Zn,Co,Mg,Ni,Fe) and ALn2CuTi2O9 (A=Ca,Ba; Ln=La,Pr,Nd,Sm)

    OpenAIRE

    Iturbe Zabalo, Edurne

    2013-01-01

    La tesis se ha centrado en la síntesis y caracterización estructural de materiales tipo perovskita: SrLnMRuO6 (Ln=La,Pr,Nd; M=Zn,Co,Mg,Ni,Fe) y ALn2CuTi2O9 (A=Ca,Ba; Ln=La,Pr,Nd,Sm). El estudio de las estructuras de los materiales se ha realizado mediante el análisis de los patrones de difracción en polvo de rayos-X, sincrotrón y/o neutrones. En el refinamiento por el método de Rietveld de las estructuras se han sustituido las coordenadas atómicas (el método más común), por coordenadas colect...

  6. Polymorphism of Bi1-xLnxO1.5 phases (04Ln2O9 (x=0.33; Ln=La, Pr, Nd)

    International Nuclear Information System (INIS)

    Drache, Michel; Huve, Marielle; Roussel, Pascal; Conflant, Pierre

    2003-01-01

    The Bi 1-x Ln x O 1.5 solid solutions (Ln=La, Pr, Nd), of the β 2 /β 1 /ε (Bi-Sr-O) structural type, have been investigated in their Ln-rich domains. For Ln=La, Pr, and Nd, the upper limits are 0.35, 0.35 and 0.33, respectively. The Bi 4 Ln 2 O 9 ε phase (x=0.33) appears to be the single definite compound. For Bi 4 La 2 O 9 , Bi 4 Pr 2 O 9 and Bi 4 Nd 2 O 9 , the ε-type cells are respectively: a=9.484(4) A, b=3.982(2) A, c=7.030(3) A, β=104.75(3) deg.; a=9.470(5) A, b=3.945(2) A, c=6.968(4) A, β=104.73(3) deg. and a=9.439(3) A, b=3.944(2) A, c=6.923(2) A, β=105.03(3) deg. . Upon heating, each monoclinic (ε) compound transforms successively into rhombohedral phases (β 2 /β 1 ) and finally into a cubic fluorite-type phase. For La- and Pr-based compounds, all transitions are reversible; for Nd, depending on the thermal treatment, the reversibility of ε→β 2 can be incomplete. These transformations are characterized using X-ray thermodiffractometry, differential thermal analysis, dilatometry and impedance spectroscopy versus temperature. Examination of Bi 4 (Ln, Ln') 2 O 9 samples allows to correlate the evolution of the thermal behavior and of the unit cell parameters, to the lanthanide size. A partial plot of the (Bi 2 O 3 ) 1-x -(La 2 O 3 ) x phase diagram (0≤x≤0.40) is proposed

  7. The single crystal structure determination of Ln{sub 6}MnSb{sub 15} (Ln=La, Ce), Ln{sub 6}Mn{sub 1-x}Zn{sub x}Sb{sub 15} (x∝0.5), and Ln{sub 6}ZnSb{sub 15} (Ln=La-Pr)

    Energy Technology Data Exchange (ETDEWEB)

    Benavides, Katherine A.; McCandless, Gregory T.; Chan, Julia Y. [Texas Univ., Dallas, Richardson, TX (United States). Dept. of Chemistry and Biochemistry

    2017-09-01

    Single crystals of Ln{sub 6}MnSb{sub 15} (Ln=La, Ce), Ln{sub 6}Mn{sub 1-x}Zn{sub x}Sb{sub 15} (x∝0.5), and Ln{sub 6}ZnSb{sub 15} (Ln=La-Pr) have been successfully grown and the compounds adopt the orthorhombic Ln{sub 6}MnSb{sub 15} structure type (space group Immm), with a∝4.3 Aa, b∝15 Aa, and c∝19 Aa. This structure is comprised of antimony nets and antimony ribbons which exhibit positional disorder at connecting points between antimony substructures, in addition to two partially occupied transition metal sites. The unit cell volumes of the La analogs displayed a systematic decrease upon Zn substitution. However, for the Ce{sub 6}Mn{sub 1-x}Zn{sub x}Sb{sub 15} and Pr{sub 6}Mn{sub 1-x}Zn{sub x}Sb{sub 15} (x∝0.5), the volumes deviate from linearity as observed in the parent compounds.

  8. Synthesis and characterization of K{sub 2}Ln{sub 2/3}Ta{sub 2}O{sub 7}·nH{sub 2}O (Ln= La, Pr, Nd), layered tantalates photo catalysts for water splitting

    Energy Technology Data Exchange (ETDEWEB)

    Valencia S, H.; Tavizon, G. [UNAM, Instituto de Quimica, Ciudad Universitaria, 04510 Ciudad de Mexico (Mexico); Pfeiffer, H. [UNAM, Instituto de Investigaciones en Materiales, Ciudad Universitaria, 04510 Ciudad de Mexico (Mexico); Acosta, D. [UNAM, Instituto de Fisica, Ciudad Universitaria, 04510 Ciudad de Mexico (Mexico); Negron M, A., E-mail: hvalencia@utp.edu.co [UNAM, Instituto de Ciencias Nucleares, Ciudad Universitaria, 04510 Ciudad de Mexico (Mexico)

    2015-07-01

    Three compounds of the K{sub 2}Ln{sub 2/3}Ta{sub 2}O{sub 7} (Ln = La, Nd, Pr) cation-deficient Ruddlesden-Popper series were prepared by the Pechini (polymeric complex) method. The crystal structures of the hydrated form of these compounds were determined by Rietveld analysis of the X-ray power diffraction data and High Resolution Transmission Electron Microscopy (HRTEM). The samples were also analyzed to determine specific area (Bet), degree of hydration (Thermogravimetric analysis), and photo catalytic activity for hydrogen evolution from water and aqueous methanol solution. (Author)

  9. Synthesis and characterization of K2Ln2/3Ta2O7·nH2O (Ln= La, Pr, Nd), layered tantalates photo catalysts for water splitting

    International Nuclear Information System (INIS)

    Valencia S, H.; Tavizon, G.; Pfeiffer, H.; Acosta, D.; Negron M, A.

    2015-01-01

    Three compounds of the K 2 Ln 2/3 Ta 2 O 7 (Ln = La, Nd, Pr) cation-deficient Ruddlesden-Popper series were prepared by the Pechini (polymeric complex) method. The crystal structures of the hydrated form of these compounds were determined by Rietveld analysis of the X-ray power diffraction data and High Resolution Transmission Electron Microscopy (HRTEM). The samples were also analyzed to determine specific area (Bet), degree of hydration (Thermogravimetric analysis), and photo catalytic activity for hydrogen evolution from water and aqueous methanol solution. (Author)

  10. A series of noncentrosymmetric antimony sulfides Ln{sub 8}Sb{sub 2}S{sub 15} (Ln = La, Pr, Nd) - syntheses, crystal and electronic structures, and NLO properties

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Hua-Jun [Laboratory of Applied Research on the Characteristic Resources in the North of Guizhou Province, School of Chemistry and Chemical Engineering, Zunyi Normal College, Guizhou (China); State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou (China); Zhou, Liu-Jiang [State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou (China)

    2015-02-15

    A series of noncentrosymmetric sulfides Ln{sub 8}Sb{sub 2}S{sub 15} (Ln = La, Pr, Nd) were prepared from stoichiometric mixtures of the elements at 1223 K in an evacuated silica tube. The compounds Ln{sub 8}Sb{sub 2}S{sub 15} with Ln = La and Nd are isostructural to Pr{sub 8}Sb{sub 2}S{sub 15} and crystallize in the tetragonal noncentrosymmetric space group I4{sub 1}cd. Their structure contains discrete [SbS{sub 3}]{sup 3-} trigonal pyramids separated by Ln{sup 3+} cations and S{sup 2-} anions. La{sub 8}Sb{sub 2}S{sub 15} shows second harmonic generation with intensities 1.2 times that of the commercially used IR NLO (nonlinear optics) material AgGaS{sub 2} (at 2.05 μm laser). It exhibits excellent thermal stability up to 663 C. Studies with UV/Vis-NIR diffuse reflectance spectroscopy show that La{sub 8}Sb{sub 2}S{sub 15} has an optical gap of around 2.3 eV, and a DFT study indicates a direct band gap with an electronic transfer excitation of S 3p electrons to a La 5d orbital. (Copyright copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  11. Enhancement of superconductivity near the pressure-induced semiconductor-metal transition in the BiS₂-based superconductors LnO₀.₅F₀.₅BiS₂ (Ln = La, Ce, Pr, Nd).

    Science.gov (United States)

    Wolowiec, C T; White, B D; Jeon, I; Yazici, D; Huang, K; Maple, M B

    2013-10-23

    Measurements of electrical resistivity were performed between 3 and 300 K at various pressures up to 2.8 GPa on the BiS2-based superconductors LnO0.5F0.5BiS2 (Ln=Pr, Nd). At lower pressures, PrO0.5F0.5BiS2 and NdO0.5F0.5BiS2 exhibit superconductivity with critical temperatures Tc of 3.5 and 3.9 K, respectively. As pressure is increased, both compounds undergo a transition at a pressure Pt from a low Tc superconducting phase to a high Tc superconducting phase in which Tc reaches maximum values of 7.6 and 6.4 K for PrO0.5F0.5BiS2 and NdO0.5F0.5BiS2, respectively. The pressure-induced transition is characterized by a rapid increase in Tc within a small range in pressure of ∼0.3 GPa for both compounds. In the normal state of PrO0.5F0.5BiS2, the transition pressure Pt correlates with the pressure where the suppression of semiconducting behaviour saturates. In the normal state of NdO0.5F0.5BiS2, Pt is coincident with a semiconductor-metal transition. This behaviour is similar to the results recently reported for the LnO0.5F0.5BiS2 (Ln=La, Ce) compounds. We observe that Pt and the size of the jump in Tc between the two superconducting phases both scale with the lanthanide element in LnO0.5F0.5BiS2 (Ln=La, Ce, Pr, Nd).

  12. High-Pressure Synthesis, Structure, and Magnetic Properties of Ge-Substituted Filled Skutterudite Compounds; LnxCo4Sb12−yGey, Ln = La, Ce, Pr, and Nd

    Directory of Open Access Journals (Sweden)

    Hiroshi Fukuoka

    2017-12-01

    Full Text Available A series of new Ge-substituted skutterudite compounds with the general composition of LnxCo4Sb12−yGey, where Ln = La, Ce, Pr, and Nd, is prepared by high-pressure and high-temperature reactions at 7 GPa and 800 °C. They have a cubic unit cell and the lattice constant for each compound is 8.9504 (3, 8.94481 (6, 8.9458 (3, and 8.9509 (4 Å for the La, Ce, Pr, and Nd derivatives, respectively. Their chemical compositions, determined by electron prove microanalysis, are La0.57Co4Sb10.1Ge2.38, Ce0.99Co4Sb9.65Ge2.51, Pr0.97Co4Sb9.52Ge2.61, and Nd0.87Co4Sb9.94Ge2.28. Their structural parameters are refined by Rietveld analysis. The guest atom size does not affect the unit cell volume. The Co–Sb/Ge distance mainly determines the unit cell size as well as the size of guest atom site. The valence state of lanthanide ions is 3+.

  13. Effect of lanthanide on the microstructure and structure of LnMn0.5Fe0.5O3 nanoparticles with Ln=La, Pr, Nd, Sm and Gd prepared by the polymer precursor method

    International Nuclear Information System (INIS)

    Romero, Mariano; Faccio, Ricardo; Martínez, Javier; Pardo, Helena; Montenegro, Benjamín; Plá Cid, Cristiani Campos; Pasa, André A.

    2015-01-01

    The synthesis of LnMn 0.5 Fe 0.5 O 3 perovskite nanoparticles by the polymer precursor method showed a strong intrinsic dependence with different lanthanides (Ln=La, Pr, Nd, Sm and Gd). The polymerization level reached in the polymer precursor was proportional to the atomic number of lanthanide with exception of samarium, which showed the formation of a different precursor based in a citrate chelate with ethyleneglycol bonded as adduct. The increasing level of polymerization of the polymer precursors showed the formation of large-size perovskite nanoparticles after its calcination. SAXS and TEM analyses suggested that nanoparticles obtained, using this method, have a squared-like microstructure in connection with the polymer precursor microstructure. Structural analysis showed an orthorhombic structure with a slight decline in the Jahn–Teller distortion when the atomic number of lanthanide increases. Mössbauer spectroscopy showed the presence of a majority site in agreement with the Pbnm orthorhombic structure best fitted with Rietveld refinements and in some cases, a more distorted site attributed to local inhomogeneities and oxygen vacancies. - Highlights: • Precursor polymerization level is lower in the presence of lighter lanthanides. • Lighter lanthanide perovskite nanoparticles after calcination are lower-sized. • Nanoparticles obtained by this method have lamellae microstructure. • Jahn–Teller distortion declines for heavier lanthanide perovskites. • Oxygen vacancy phase was observed in lighter lanthanide perovskites

  14. Chemical and structural changes in Ln{sub 2}NiO{sub 4+δ} (Ln=La, Pr or Nd) lanthanide nickelates as a function of oxygen partial pressure at high temperature

    Energy Technology Data Exchange (ETDEWEB)

    Flura, Aurélien; Dru, Sophie; Nicollet, Clément; Vibhu, Vaibhav; Fourcade, Sébastien; Lebraud, Eric; Rougier, Aline; Bassat, Jean-Marc; Grenier, Jean-Claude, E-mail: grenier@icmcb-bordeaux.cnrs.fr

    2015-08-15

    The chemical stability of lanthanide nickelates Ln{sub 2}NiO{sub 4+δ} (Ln=La, Pr or Nd) has been studied in the temperature range 25–1300 °C, either in air or at low pO{sub 2} (down to 10{sup −4} atm). Thermal gravimetry analysis (TGA) measurements coupled with X-ray diffraction (XRD) characterization have shown that all compounds retain their K{sub 2}NiF{sub 4}-type structure in these conditions, while remaining over-stoichiometric in oxygen up to 1000 °C. Only Nd{sub 2}NiO{sub 4+δ} starts to decompose into Nd{sub 2}O{sub 3} and NiO above 1000 °C, at pO{sub 2}=10{sup −4} atm. In addition, a careful analysis of the lanthanide nickelates structural features has been performed by in situ XRD, as a function of temperature and pO{sub 2}. For all compounds, a structural transition has been always observed in the temperature range 200–400 °C, in air or at pO{sub 2}=10{sup −4} atm. In addition, their cell volume did not vary upon the variation of the oxygen partial pressure. Therefore, these materials do not exhibit a chemical expansion in these conditions, which is beneficial for a fuel cell application as cathode layers. Additional dilatometry measurements have revealed that a temperature as high as 950 °C for Pr{sub 2}NiO{sub 4+δ} or 1100 °C for La{sub 2}NiO{sub 4+δ} and Nd{sub 2}NiO{sub 4+δ} has to be reached in order to begin the sintering of the material particles, which is of primary importance to obtain an efficient electronic/ionic conduction in the corresponding designed cathode layers. Besides, excellent matching was found between the thermal expansion coefficients of lanthanide nickelates and SOFC electrolytes such as 8wt% yttria stabilized zirconia (8YSZ) or Ce{sub 0.8}Gd{sub 0.2}O{sub 2−δ} (GDC), at least from 400 °C up to 1400 °C in air or up to 1200 °C at pO{sub 2}=10{sup −4} atm. - Graphical abstract: This study reports the good chemical stability of oxygen overstoichiometric Ln2NiO4+δ(Ln = La, Pr or Nd) at high temperatures

  15. New family of lanthanide-based inorganic-organic hybrid frameworks: Ln2(OH)4[O3S(CH2)nSO3]·2H2O (Ln = La, Ce, Pr, Nd, Sm; n = 3, 4) and their derivatives.

    Science.gov (United States)

    Liang, Jianbo; Ma, Renzhi; Ebina, Yasuo; Geng, Fengxia; Sasaki, Takayoshi

    2013-02-18

    We report the synthesis and structure characterization of a new family of lanthanide-based inorganic-organic hybrid frameworks, Ln(2)(OH)(4)[O(3)S(CH(2))(n)SO(3)]·2H(2)O (Ln = La, Ce, Pr, Nd, Sm; n = 3, 4), and their oxide derivatives. Highly crystallized samples were synthesized by homogeneous precipitation of Ln(3+) ions from a solution containing α,ω-organodisulfonate salts promoted by slow hydrolysis of hexamethylenetetramine. The crystal structure solved from powder X-ray diffraction data revealed that this material comprises two-dimensional cationic lanthanide hydroxide {[Ln(OH)(2)(H(2)O)](+)}(∞) layers, which are cross-linked by α,ω-organodisulfonate ligands into a three-dimensional pillared framework. This hybrid framework can be regarded as a derivative of UCl(3)-type Ln(OH)(3) involving penetration of organic chains into two {LnO(9)} polyhedra. Substitutional modification of the lanthanide coordination promotes a 2D arrangement of the {LnO(9)} polyhedra. A new hybrid oxide, Ln(2)O(2)[O(3)S(CH(2))(n)SO(3)], which is supposed to consist of alternating {[Ln(2)O(2)](2+)}(∞) layers and α,ω-organodisulfonate ligands, can be derived from the hydroxide form upon dehydration/dehydroxylation. These hybrid frameworks provide new opportunities to engineer the interlayer chemistry of layered structures and achieve advanced functionalities coupled with the advantages of lanthanide elements.

  16. Synthesis, crystal and electronic structures, and magnetic properties of LiLn{sub 9}Mo{sub 16}O{sub 35} (Ln=La, Ce, Pr, and Nd) compounds containing the original cluster Mo{sub 16}O{sub 36}

    Energy Technology Data Exchange (ETDEWEB)

    Gougeon, Patrick; Gall, Philippe [UMR CNRS 6226 - ' ' Sciences Chimiques de Rennes' ' , Universite de Rennes 1 - INSA (France); Cuny, Jerome; Gautier, Regis; Le Polles, Laurent [UMR CNRS 6226 - ' ' Sciences Chimiques de Rennes' ' , Ecole Nationale Superieure de Chimie de Rennes (France); Delevoye, Laurent; Trebosc, Julien [UMR CNRS 8181 - UCCS, ENSCL, Universite Lille Nord de France, Villeneuve d' Ascq (France)

    2011-12-02

    The new compounds LiLn{sub 9}Mo{sub 16}O{sub 35} (Ln=La, Ce, Pr, and Nd) were synthesized from stoichiometric mixtures of Li{sub 2}MoO{sub 4}, Ln{sub 2}O{sub 3}, Pr{sub 6}O{sub 11} or CeO{sub 2}, MoO{sub 3}, and Mo heated at 1600 C for 48 h in a molybdenum crucible sealed under a low argon pressure. The crystal structure, determined from a single crystal of the Nd member, showed that the main building block is the Mo{sub 16}O{sub 36} unit, the Mo{sub 16} core of which is totally new and results from the fusion of two bioctahedral Mo{sub 10} clusters. It can also be viewed as a fragment of an infinite twin chain of edge-sharing Mo{sub 6} octahedra. The Mo{sub 16}O{sub 36} cluster units share some oxygen atoms to form infinite chains running parallel to the b axis, which are separated by the rare-earth and lithium cations. {sup 7}Li-NMR experiments, carried out at high field on the nonmagnetic LiLa{sub 9}Mo{sub 16}O{sub 35}, provided insights into the local environment of the lithium ions. Magnetic susceptibility measurements confirmed the trivalent oxidation state of the magnetic rare-earth cations and indicated the absence of localized moments on the Mo{sub 16} clusters. The electronic structure of the LiLn{sub 9}Mo{sub 16}O{sub 35} compounds was analyzed using molecular and periodic quantum calculations. The study of the molecular orbital diagrams of isolated Mo{sub 16}O{sub 36} models allowed the understanding of this unique metallic architecture. Periodic density functional theory calculations demonstrated that few interactions occur between the Mo{sub 16} clusters, and predicted semiconducting properties for LiLn{sub 9}Mo{sub 16}O{sub 35} as a band gap of 0.57 eV was computed for the lanthanum phase. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  17. U(SMes*)n, (n=3, 4) and Ln(SMes*)3 (Ln = La, Ce, Pr, Nd): Lanthanide(III)/actinide(III) differentiation in agostic interactions and an unprecedented eta(3) Ligation mode of the aryl-thiolate ligand, from X-ray diffraction and DFT analysis

    International Nuclear Information System (INIS)

    Roger, Mathieu; Barros, Noemi; Arliguie, Therese; Thuery, Pierre; Maron, Laurent; Ephritikhine, Michel

    2006-01-01

    Reaction of U(NEt 2 ) 4 with HS-2,4,6- t Bu 3 C 6 H 2 (HSMes*) gave U(SMes*) 3 (NEt 2 )(py) (1), whereas similar treatment of U[N(SiMe 3 )SiMe 2 CH 2 ][N(SiMe 3 ) 2 ] 2 afforded U(SMes*)[N(SiMe 3 ) 2 ] 3 (2) and U(SMes*) 3 [N(SiMe 3 ) 2 ]. The first neutral homoleptic uranium(IV) thiolate to have been crystallographically characterized, U(SMes*) 4 (4), was isolated from the reaction of U(BH 4 ) 4 and KSMes*. The first homoleptic thiolate complex of uranium(III), U(SMes*) 3 (5), was synthesized by proton-lysis of U[N(SiMe 3 ) 2 ] 3 with HSMes* in cyclohexane. The crystal structure of 5 exhibits the novel η 3 ligation mode for the aryl-thiolate ligand. Comparison of the crystal structure of 5 with those of the isomorphous lanthanide congeners Ln(SMes*) 3 (Ln) La, Ce, Pr, and Nd) indicates that the U-S, U-C ipso , and U-C ortho bond lengths are shorter than the corresponding ones in the 4f-element analogues, when taking into account the variation in the ionic radii of the metals. The distance between the uranium and the carbon atoms involved in the U center dot center dot center dot H-C ε agostic interaction of each thiolate ligand is shorter, by ∼ 0.05 angstrom, than that expected from a purely ionic bonding model. The lanthanide( III)/actinide(III) differentiation was analyzed by density functional theory (DFT). The nature of the M-S bond is shown to be ionic strongly polarized at the sulfur for M) U and ion-covalent (i.e. strongly ionic with low orbital interaction), for M) Ln. The strength of the U center dot center dot center dot H-C ε agostic interaction is proposed to be controlled by the maximization of the interaction between U + and S - under steric constraints. The η 3 ligation mode of the aryl-thiolate ligand is also obtained from DFT. (authors)

  18. U(SMes*)n, (n = 3, 4) and Ln(SMes*)3 (Ln = La, Ce, Pr, Nd): lanthanide(III)/actinide(III) differentiation in agostic interactions and an unprecedented eta3 ligation mode of the arylthiolate ligand, from X-ray diffraction and DFT analysis.

    Science.gov (United States)

    Roger, Mathieu; Barros, Noémi; Arliguie, Thérèse; Thuéry, Pierre; Maron, Laurent; Ephritikhine, Michel

    2006-07-12

    Reaction of U(NEt(2))(4) with HS-2,4,6-(t)Bu(3)C(6)H(2) (HSMes) gave U(SMes)(3)(NEt(2))(py) (1), whereas similar treatment of U[N(SiMe(3))SiMe(2)CH(2)][N(SiMe(3))(2)](2) afforded U(SMes)[N(SiMe(3))(2)](3) (2) and U(SMes)(3)[N(SiMe(3))(2)]. The first neutral homoleptic uranium(IV) thiolate to have been crystallographically characterized, U(SMes)(4) (4), was isolated from the reaction of U(BH(4))(4) and KSMes. The first homoleptic thiolate complex of uranium(III), U(SMes)(3) (5), was synthesized by protonolysis of U[N(SiMe(3))(2)](3) with HSMes in cyclohexane. The crystal structure of 5 exhibits the novel eta(3) ligation mode for the arylthiolate ligand. Comparison of the crystal structure of 5 with those of the isomorphous lanthanide congeners Ln(SMes)(3) (Ln = La, Ce, Pr, and Nd) indicates that the U-S, U-C(ipso)(), and U-C(ortho)() bond lengths are shorter than the corresponding ones in the 4f-element analogues, when taking into account the variation in the ionic radii of the metals. The distance between the uranium and the carbon atoms involved in the U...H-C epsilon agostic interaction of each thiolate ligand is shorter, by approximately 0.05 A, than that expected from a purely ionic bonding model. The lanthanide(III)/actinide(III) differentiation was analyzed by density functional theory (DFT). The nature of the M-S bond is shown to be ionic strongly polarized at the sulfur for M = U and iono-covalent (i.e. strongly ionic with low orbital interaction), for M = Ln. The strength of the U...H-C epsilon agostic interaction is proposed to be controlled by the maximization of the interaction between U(+) and S(-) under steric constraints. The eta(3) ligation mode of the arylthiolate ligand is also obtained from DFT.

  19. ALnS2:RE (A=K, Rb; Ln=La, Gd, Lu, Y): New optical materials family

    International Nuclear Information System (INIS)

    Jarý, V.; Havlák, L.; Bárta, J.; Mihóková, E.; Buryi, M.; Nikl, M.

    2016-01-01

    In the presented review paper, new potentially interesting material family, RE-doped ternary sulfides ALnS 2 (RE=Ce, Pr, Sm, Eu, Tb, Tm; A=Rb, K; Ln=La, Gd, Lu, Y) is discussed. Their synthesis is described and the structural and optical properties, characterized by methods of X-ray diffraction, time-resolved luminescence spectroscopy and electron paramagnetic resonance, are summarized and reviewed especially with respect to the influence of their composition. All samples discussed were synthesized in the form of transparent crystalline hexagonal platelets by chemical reaction under the flow of hydrogen sulfide. Their luminescence characteristics, including absorption, radioluminescence, photoluminescence excitation and emission spectra and decay kinetics, were measured and evaluated in a broad temperature (8–800 K) and concentration (0.002–20% of dopants) range. The application potential of mentioned compounds in the field of white LED solid state lightings or X-ray phosphors is thoroughly discussed. - Highlights: • RE-doped ALnS 2 (A=K, Rb; Ln=La, Gd, Lu, Y) were synthesized. • Their optical characteristics are summarized. • Concentration and temperature dependences of luminescence features investigated. • EPR technique is employed to explain Eu 2+ incorporation into KLuS 2 host. • The application potential in white LED and X-ray phosphors is discussed.

  20. Prism inside. Spectroscopic and magnetic properties of the lanthanide(III) chloride oxidotungstates(VI) Ln{sub 3}Cl{sub 3}[WO{sub 6}] (Ln = La - Nd, Sm - Tb)

    Energy Technology Data Exchange (ETDEWEB)

    Dorn, Katharina V.; Blaschkowski, Bjoern; Hartenbach, Ingo [Institute for Inorganic Chemistry, University of Stuttgart (Germany); Foerg, Katharina; Netzsch, Philip; Hoeppe, Henning A. [Institute for Physics, University of Augsburg (Germany)

    2017-11-17

    The lanthanide(III) chloride oxidotungstates(VI) with the formula Ln{sub 3}Cl{sub 3}[WO{sub 6}] for Ln = La - Nd, Sm - Tb were synthesized by solid-state reactions utilizing the respective lanthanide trichloride, lanthanide sesquioxide (where available), and tungsten trioxide together with lithium chloride as flux. The title compounds crystallize hexagonally in space group P6{sub 3}/m (no. 176, a = 941-909, c = 543-525 pm, Z = 2). The structures comprise crystallographically unique Ln{sup 3+} cations surrounded by six O{sup 2-} and four Cl{sup -} anions (C.N. = 10) forming distorted tetracapped trigonal prisms as well as rather uncommon trigonal prismatic [WO{sub 6}]{sup 6-} units, whose edges are coordinated by nine Ln{sup 3+} cations. Thus, a {sup 3}{sub ∞}{([WO_6]Ln"e_9_/_3)"3"+} framework (e = edge-sharing) is created, which contains tube-shaped channels along [001] lined with chloride anions. To elucidate the spectroscopic and magnetic properties of the obtained pure phase samples, single-crystal Raman (for Ln = La - Nd, Sm-Tb), diffuse reflectance (for Ln = La, Pr, Nd, Gd), and luminescence spectroscopy (for bulk Ln{sub 3}Cl{sub 3}[WO{sub 6}] (Ln = La, Eu, Gd, Tb) and Eu{sup 3+}- or Tb{sup 3+}-doped derivatives of La{sub 3}Cl{sub 3}[WO{sub 6}] and Gd{sub 3}Cl{sub 3}[WO{sub 6}], respectively) were performed and their temperature-dependent magnetic moments (for Ln = Pr, Nd, Gd) were determined. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  1. Enhanced visible light-responsive photocatalytic activity of LnFeO3 (Ln = La, Sm) nanoparticles by synergistic catalysis

    International Nuclear Information System (INIS)

    Li, Li; Wang, Xiong; Zhang, Yange

    2014-01-01

    Highlights: • LnFeO 3 (Ln = La, Sm) nanoparticles were prepared by a facile sol–gel method. • The samples exhibit superior visible-light-responsive photocatalytic activity. • Synergistic effect will enhance the photodegradation of RhB under visible light. - Abstract: LnFeO 3 (Ln = La, Sm) nanoparticles were prepared by a facile sol–gel method with assistance of glycol at different calcination temperatures. The as-synthesized LnFeO 3 was characterized by X-ray diffraction, transmission electron microscopy, differential scanning calorimeter and thermogravimetric analysis, and UV–vis absorption spectroscopy. The photocatalytic behaviors of LnFeO 3 nanoparticles were evaluated by photodegradation of rhodamine B under visible light irradiation. The results indicate that the visible light-responsive photocatalytic activity of LnFeO 3 nanoparticles was enhanced remarkably by the synergistic effect between the semiconductor photocatalysis and Fenton-like reaction. And a possible catalytic mechanism was also proposed based on the experimental results

  2. Characteristic charge transport in oxygen-deficiency-controlled LnFeAsO1-y (Ln = La and Nd)

    International Nuclear Information System (INIS)

    Ishida, Shigeyuki; Nakajima, Masamichi; Tomioka, Yasuhide; Ito, Toshimitsu; Miyazawa, Kiichi; Kito, Hijiri; Lee, Chul-Ho; Ishikado, Motoyuki; Shamoto, Shin-ichi; Iyo, Akira; Eisaki, Hiroshi; Kojima, Kenji M.; Uchida, Shin-ichi

    2010-01-01

    We have investigated the transport properties of LnFeAsO 1-y (Ln = La, Nd) over a wide range of doping. When we compare the exponent n of resistivity ρ(T)∼T n , a marked difference is found between La and Nd system. In the La system with lower T C ,ρ(T) is always dominated by a T 2 term at low temperatures, showing relatively large magnetoresistance. On the other hand, in the Nd system with higher T C ,ρ(T) is linear on T with a small magnetoresistance. These results indicate that the carriers are subject to stronger scattering in NdFeAsO 1-y , which might be linked to the higher T C .

  3. Phase transformations during HLnTiO{sub 4} (Ln=La, Nd) thermolysis and photocatalytic activity of obtained compounds

    Energy Technology Data Exchange (ETDEWEB)

    Silyukov, Oleg I., E-mail: olegsilyukov@yandex.ru; Abdulaeva, Liliia D.; Burovikhina, Alena A.; Rodionov, Ivan A.; Zvereva, Irina A.

    2015-03-15

    Layered HLnTiO{sub 4} (Ln=La, Nd) compounds belonging to Ruddlesden–Popper phases were found to form partially hydrated compounds Ln{sub 2}Ti{sub 2}O{sub 7}·xH{sub 2}O during thermal dehydration as well as defect oxides Ln{sub 2}□Ti{sub 2}O{sub 7} as final products. Further heating of metastable defect Ln{sub 2}□Ti{sub 2}O{sub 7} substances leads to the formation of pyrochlore-type oxides Ln{sub 2}Ti{sub 2}O{sub 7} {sub (p)}, with subsequent transformation under higher temperatures to stable layered 110-type perovskites Ln{sub 2}Ti{sub 2}O{sub 7}. The occurring structure transformations lead to an increase of photocatalytic activity in the order of HLnTiO{sub 4}Ln=La, Nd) compounds form partially hydrated Ln{sub 2}Ti{sub 2}O{sub 7}·xH{sub 2}O compounds during thermal dehydration, further heating results to the formation to defect oxides Ln{sub 2}□Ti{sub 2}O{sub 7}, pyrochlor-type oxides Ln{sub 2}Ti{sub 2}O{sub 7} {sub (p)}, with subsequent transformation to layered 110-type perovskites Ln{sub 2}Ti{sub 2}O{sub 7}. Structure transformations lead to an increase of photocatalytic activity in the order of HLnTiO{sub 4}Ln=La, Nd) compounds. • XRD, STA and solid state IR studies were carried out. • A new series of metastable Ln{sub 2}Ti{sub 2}O{sub 7}·yH{sub 2}O compounds was obtained. • We examined the photocatalytic activity of all obtained compounds. The hydrogen evolution rate increased in the course of the structure changes during thermolysis.

  4. Low-Temperature Transformations of Protonic Forms of Layered Complex Oxides HLnTiO4 and H2Ln2Ti3O10 (Ln = La, Nd)

    International Nuclear Information System (INIS)

    Abdulaeva, L.D.; Silyukov, O.I.; Zvereva, I.A.; Petrov, Yu.V.

    2013-01-01

    In the present work protonic forms of layered Ruddlesden-Popper oxides HLnTiO 4 and H 2 Ln 2 Ti 3 O 10 (Ln = La, Nd) were used as the starting point for soft chemistry synthesis of two series of perovskite-like compounds by acid leaching and exfoliation, promoted by vanadyl sulfate. The last route leads to the nano structured VO 2+ containing samples. Characterization by SEM, powder XRD, and TGA has been performed for the determination of the structure and composition of synthesized oxides

  5. Hydrothermal synthesis and luminescent properties of LnPO4:Tb,Bi (Ln=La,Gd) phosphors under UV/VUV excitation

    International Nuclear Information System (INIS)

    Wang Yuhua; Wu Chunfang; Wei Jie

    2007-01-01

    Monoclinic LnPO 4 :Tb,Bi (Ln=La,Gd) phosphors were prepared by hydrothermal reaction and their luminescent properties under ultraviolet (UV) and vacuum ultraviolet (VUV) excitation were investigated. LaPO 4 :Tb,Bi phosphor and GdPO 4 :Tb phosphor showed the strongest emission intensity under 254 and 147 nm excitation, respectively, because of the different energy transfer models. In UV region, Bi 3+ absorbed most energy then transferred to Tb 3+ , but in VUV region it was the host which absorbed most energy and transferred to Tb 3+

  6. Rare earth ruthenium gallides with the ideal composition Ln_2Ru_3Ga_5 (Ln = La-Nd, Sm) crystallizing with U_2Mn_3Si_5 (Sc_2Fe_3Si_5) type structure

    International Nuclear Information System (INIS)

    Jeitschko, Wolfgang; Schlueter, Martin

    2010-01-01

    The rare earth ruthenium gallides Ln_2Ru_3Ga_5 (Ln = La, Ce, Pr, Nd, Sm) were prepared by arc-melting of cold-pressed pellets of the elemental components. They crystallize with a tetragonal structure (P4/mnc, Z = 4) first reported for U_2Mn_3Si_5. The crystal structures of the cerium and samarium compounds were refined from single-crystal X-ray data, resulting in significant deviations from the ideal compositions: Ce_2Ru_2_._3_1_(_1_)Ga_5_._6_9_(_1_), a = 1135.10(8) pm, c = 580.58(6) pm, R_F = 0.022 for 742 structure factors; Sm_2Ru_2_._7_3_(_2_)Ga_5_._2_7_(_2_), a = 1132.95(9) pm, c = 562.71(6) pm, R_F = 0.026 for 566 structure factors and 32 variable parameters each. The deviations from the ideal compositions 2:3:5 are discussed. A mixed Ru/Ga occupancy occurs only for one atomic site. The displacement parameters are relatively large for atoms with mixed occupancy within their coordination shell and small for atoms with no neighboring sites of mixed occupancy. Chemical bonding is analyzed on the basis of interatomic distances. Ln-Ga bonding is stronger than Ln-Ru bonding. Ru-Ga bonding is strong and Ru-Ru bonding is weak. The Ga-Ga interactions are of similar strength as in elemental gallium. (Abstract Copyright [2010], Wiley Periodicals, Inc.)

  7. High-pressure investigations of lanthanoid oxoarsenates. I. Single crystals of scheelite-type Ln[AsO{sub 4}] phases with Ln = La-Nd from monazite-type precursors

    Energy Technology Data Exchange (ETDEWEB)

    Metzger, Sebastian J.; Ledderboge, Florian; Schleid, Thomas [Stuttgart Univ. (Germany). Inst. fuer Anorganische Chemie; Heymann, Gunter; Huppertz, Hubert [Innsbruck Univ. (Austria). Inst. fuer Allgemeine, Anorganische und Theoretische Chemie

    2016-08-01

    Transparent single crystals of the scheelite-type Ln[AsO{sub 4}] phases with Ln = La-Nd are obtained by the pressure-induced monazite-to-scheelite type phase transition in a Walker-type module under high-pressure and high-temperature conditions of 11 GPa at 1100-1300 C. Coinciding with this transition, there is an increase in density and a reduction in molar volume of about 4.5 % for the scheelite-type phases (tetragonal, I4{sub 1}/a) for La[AsO{sub 4}] (a = 516.92(4), c = 1186.1(9) pm), Ce[AsO{sub 4}] (a = 514.60(1), c = 1175.44(2) pm), Pr[AsO{sub 4}] (a = 512.63(4), c = 1168.25(9) pm), and Nd[AsO{sub 4}] (a = 510.46(4), c = 1160.32(11) pm) as compared to the well-known monazite-type phases (monoclinic, P2{sub 1}/n). Surprisingly enough, the scheelite-type oxoarsenates(V) exhibit a lower coordination number for the Ln{sup 3+} cations (CN = 8 versus CN = 8 + 1), whereas the isolated tetrahedral [AsO{sub 4}]{sup 3-} anions (d(As-O) = 168.9-169.3 pm for the scheelites as compared to d(As-O) = 167.1-169.9 pm for the monazites) remain almost unchanged. So the densification must occur because of the loss of two edge-connections of the involved [LnO{sub 8+1}]{sup 15-} polyhedra with the [AsO{sub 4}]{sup 3-} tetrahedra in the monazite- resulting in exclusively vertex connected [LnO{sub 8}]{sup 13-} and [AsO{sub 4}]{sup 3-} units in the scheelite-type structure.

  8. Phase equilibria in the MgMoO4-Ln2(MoO4)3 (Ln=La,Gd) systems

    International Nuclear Information System (INIS)

    Fedorov, N.F.; Ipatov, V.V.; Kvyatkovskij, O.V.

    1980-01-01

    Phase equilibria in the MgMoO 4 -Ln 2 (MoO 4 ) 3 systems (Ln=La, Gd) have been studied by static and dynamic methods of the physico-chemical analysis, using differential thermal, visual-polythermal, crystal-optical, X-ray phase, and infrared spectroscopic methods, and their phase diagrams have been constructed. Phase equilibria in the systems studied are characterized by limited solubility of components in the liquid state, formation of solid solutions on the base of α- and β-forms of Gd 2 (MoO 4 ) 3 . Eutectics in the MgMoO 4 -Ln 2 (MoO 4 ) 3 (Ln=La, Gd) systems corresponds to the composition of 71 mode % La 2 (MoO 4 ) 3 -29 mole % MgMoO 4 , tsub(melt)--935+-5 deg C and 57 mole % Gd 2 (MoO 4 ) 3 -43 mole % MgMoO 4 , tsub(melt)=1020+-5 deg C. The region of glass formation has been established [ru

  9. Ln28Ti2O7 (Ln = La, Nd, Sm, Gd): a novel series of defective Ruddlesden–Popper phases formed by topotactic dehydration of HLnTiO4

    OpenAIRE

    Thangadurai, V; Subbanna, GN; Gopalakrishnan, J

    1998-01-01

    Topotactic dehydration of HLnTiO4 (Ln = La, Nd, Sm or Gd) around 480–500 °C yields a new series of metastable layered perovskite oxides, Ln28Ti2O7, that possess a defective Sr3Ti2O7 structure, where the cubooctahedral sites within the double-perovskite layers are most likely vacant.

  10. Structure and properties of novel cobaltates Ln.sub.0.3./sub.CoO.sub.2./sub. (Ln = La, Pr, and Nd)

    Czech Academy of Sciences Publication Activity Database

    Knížek, Karel; Jirák, Zdeněk; Hejtmánek, Jiří; Maryško, Miroslav; Buršík, Josef

    2012-01-01

    Roč. 111, č. 7 (2012), "07D707-1"-"07D707-3" ISSN 0021-8979 R&D Projects: GA ČR GA203/09/1036; GA ČR GA202/09/0421 Institutional research plan: CEZ:AV0Z10100521; CEZ:AV0Z40320502 Keywords : thermoelectric and thermomagnetic effects * heat capacity * saturation moments and magnetic susceptibilities * nonmetals * Insulators * low-field transport Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 2.210, year: 2012

  11. Systematic and material independent variation of electrical, optical, and chemical properties of Ln-materials over the Ln-series (Ln=La,Ce,Pr,..,Lu)

    NARCIS (Netherlands)

    Van der Kolk, E.; Dorenbos, P.

    2007-01-01

    A model is presented that successfully predicts electro-optical properties of Lanthanide materials, irrespective whether these materials are inorganic or organic, diluted or concentrated, metallic, semi-conducting or insulating. The model is firmly based on recent experimental data revealing that

  12. Observation of Vacancies, Faults, and Superstructures in Ln5Mo2O12 (Ln = La, Y, and Lu) Compounds with Direct Mo-Mo Bonding.

    Science.gov (United States)

    Colabello, Diane M; Sobalvarro, Elizabeth M; Sheckelton, John P; Neuefeind, Joerg C; McQueen, Tyrel M; Khalifah, Peter G

    2017-11-06

    Among oxide compounds with direct metal-metal bonding, the Y 5 Mo 2 O 12 (A 5 B 2 O 12 ) structural family of compounds has a particularly intriguing low-dimensional structure due to the presence of bioctahedral B 2 O 10 dimers arranged in one-dimensional edge-sharing chains along the direction of the metal-metal bonds. Furthermore, these compounds can have a local magnetic moment due to the noninteger oxidation state (+4.5) of the transition metal, in contrast to the conspicuous lack of a local moment that is commonly observed when oxide compounds with direct metal-metal bonding have integer oxidation states resulting from the lifting of orbital degeneracy typically induced by the metal-metal bonding. Although a monoclinic C2/m structure has been previously proposed for Ln 5 Mo 2 O 12 (Ln = La-Lu and Y) members of this family based on prior single crystal diffraction data, it is found that this structural model misses many important structural features. On the basis of synchrotron powder diffraction data, it is shown that the C2/m monoclinic unit cell represents a superstructure relative to a previously unrecognized orthorhombic Immm subcell and that the superstructure derives from the ordering of interchangeable Mo 2 O 10 and LaO 6 building blocks. The superstructure for this reason is typically highly faulted, as evidenced by the increased breadth of superstructure diffraction peaks associated with a coherence length of 1-2 nm in the c* direction. Finally, it is shown that oxygen vacancies can occur when Ln = La, producing an oxygen deficient stoichiometry of La 5 Mo 2 O 11.55 and an approximately 10-fold reduction in the number of unpaired electrons due to the reduction of the average Mo valence from +4.5 to +4.05, a result confirmed by magnetic susceptibility measurements. This represents the first observation of oxygen vacancies in this family of compounds and provides an important means of continuously tuning the magnetic interactions within the one

  13. Optical, Structural and Paramagnetic Properties of Eu-Doped Ternary Sulfides ALnS2 (A = Na, K, Rb; Ln = La, Gd, Lu, Y

    Directory of Open Access Journals (Sweden)

    Vítězslav Jarý

    2015-10-01

    Full Text Available Eu-doped ternary sulfides of general formula ALnS2 (A = Na, K, Rb; Ln = La, Gd, Lu, Y are presented as a novel interesting material family which may find usage as X-ray phosphors or solid state white light emitting diode (LED lighting. Samples were synthesized in the form of transparent crystalline hexagonal platelets by chemical reaction under the flow of hydrogen sulfide. Their physical properties were investigated by means of X-ray diffraction, time-resolved photoluminescence spectroscopy, electron paramagnetic resonance, and X-ray excited fluorescence. Corresponding characteristics, including absorption, radioluminescence, photoluminescence excitation and emission spectra, and decay kinetics curves, were measured and evaluated in a broad temperature range (8–800 K. Calculations including quantum local crystal field potential and spin-Hamiltonian for a paramagnetic particle in D3d local symmetry and phenomenological model dealing with excited state dynamics were performed to explain the experimentally observed features. Based on the results, an energy diagram of lanthanide energy levels in KLuS2 is proposed. Color model xy-coordinates are used to compare effects of dopants on the resulting spectrum. The application potential of the mentioned compounds in the field of white LED solid state lighting or X-ray phosphors is thoroughly discussed.

  14. Relaxor-ferroelectric BaLnZT (Ln = La, Nd, Sm, Eu, and Sc) ceramics for actuator and energy storage application

    Science.gov (United States)

    Ghosh, Sarit K.; Mallick, Kaushik; Tiwari, B.; Sinha, E.; Rout, S. K.

    2018-01-01

    Lead free ceramics Ba1-x Ln2x/3Zr0.3Ti0.7O3 (Ln = La, Nd, Sm, Eu and Sc), x = 0.02-0.10 are investigated for electrostrictive effect and energy storage properties in the proximity of relaxor-paraelectric phase boundary. Relaxor phase evidence from slim hysteresis loop and low remnant polarization are the key parameters responsible for improve the electrostrictive effect and energy storage properties simultaneously. With increase in rare earth content negative strain disappeared and almost hysteresis free strain is achieved. Strain-hysteresis profile in term of S-E, S-E 2 and S-P 2 is used to analyze the electrostrictive behavior of these ceramics. An average strain (S%) ˜ 0.03%, is accomplished at initial concentrations of x = 0.02-0.04 and electrostrictive coefficients (Q 11, and M 11) as well as the energy storage density is improved by a factor of 1.2 and 2.6 respectively when compare with pure (x = 0.0) ceramic. Above x ≥ 0.06, all compositions show a stable behavior which suggested the possibilities of these relaxor ceramics towards high precision actuators and energy storage application.

  15. Formation of high oxide ion conductive phases in the sintered oxides of the system Bi2O3-Ln2O3 (Ln = La-Yb)

    International Nuclear Information System (INIS)

    Iwahara, H.; Esaka, T.; Sato, T.; Takahashi, T.

    1981-01-01

    The electrical conduction in various phases of the system Bi 2 O 3 -Ln 2 O 3 (Ln = La, Nd, Sm, Dy, Er, or Yb) was investigated by measuring ac conductivity and the emf of the oxygen gas concentration cell. High-oxide-ion conduction was observed in the rhombohedral and face-centered cubic (fcc) phase in these systems. The fcc phase could be stabilized over a wide range of temperature by adding a certain amount of Ln 2 O 3 . In these cases, the larger the atomic number of Ln, the lower the content of Ln 2 O 3 required to form the fcc solid solution, except in the case of Yb 2 O 3 . The oxide ion conductivity of this phase decreased with increasing content of Ln 2 O 3 . Maximum conductivity was obtained at the lower limit of the fcc solid solution formation range in each system, which was more than one order of magnitude higher than those of conventional stabilized zirconias. Lattice parameters of the fcc phase were calculated from the x-ray diffraction patterns. The relationship between the oxide ion conductivity and the lattice parameter was also discussed

  16. Synthesis and characterisation of the n = 2 Ruddlesden–Popper phases Ln2Sr(Ba)Fe2O7 (Ln = La, Nd, Eu)

    International Nuclear Information System (INIS)

    Gurusinghe, Nicola N.M.; Figuera, Juand de la; Marco, José F.; Thomas, Michael F.; Berry, Frank J.; Greaves, Colin

    2013-01-01

    Graphical abstract: - Highlights: • Some Ruddlesden–Popper phases have been characterised. • Substitution on the A site influences cationic order. • The magnetic moment redirects with temperature - Abstract: A series of n = 2 Ruddlesden–Popper phases A 2 B 2 O 7 of composition Ln 2 Sr(Ba)Fe 2 O 7 (Ln = La, Nd, Eu) have been prepared. La 2 SrFe 2 O 7 and La 2 BaFe 2 O 7 crystallise in the tetragonal space group I4/mmm. The structures of Eu 2 SrFe 2 O 7 and Nd 2 SrFe 2 O 7 are best described in space group P4 2 /mnm. Substitution on the A site with smaller lanthanide- and larger alkaline metal- ions leads to enhanced cationic order in these phases and reflects increasing differences in cationic radii. All the compounds are antiferromagnetically ordered between 298 and 2 K. In La 2 SrFe 2 O 7 the magnetic moment lies along [1 1 0] at all temperatures between 298 and 2 K whereas in La 2 BaFe 2 O 7 the magnetic moment at 298 K lies along the crystallographic x-axis but redirects from the [1 0 0] to the [1 1 0] direction between 210 and 190 K and is retained in this direction until 2 K. In Nd 2 SrFe 2 O 7 the magnetic moment at 298 K lies along [1 1 0] but rotates from [1 1 0] to [0 0 1] between 17 and 9 K. A series of 57 Fe Mössbauer spectra recorded from La 2 SrFe 2 O 7 between 290 and 600 K indicate a magnetic ordering temperature of T N ≥ 535 K

  17. Dissolution of LnYSiAlO glass (Ln=La or Ce) in aqueous media. Part 3. Influence of β irradiation on structure and hydrolysis mechanisms

    International Nuclear Information System (INIS)

    Gavarini, S.; Carrot, F.; Trocellier, P.; Boizot, B.; Matzen, G.

    2003-01-01

    LnYSiAlO glasses (Ln=La or Ce) are considered as potential matrices for the specific storage of minor actinides. β particles emitted during the disintegration of fission products may cause important modifications to the glass network through electronic excitation and ionization. The influence of these processes on the structure of two analogous compositions of glass, involving La or Ce, and the consequences for their chemical durability were studied. Monoliths of glasses were irradiated with electrons that had been accelerated to 2.5 MeV and samples were then leached in static bidistilled water for one month at 90 C. Raman spectrometry, 27 Al MAS-NMR and EPR spectrometry experiments, performed after irradiation, globally indicated weak structural modifications. The two main effects of irradiation were an increase of the (Al IV )/(Al VI +Al V ) ratio and the formation of a paramagnetic center in the case of La-glass (g∼1.99). The former observation could indicate a slight migration and segregation of the rare earth, preferentially surrounded by highly charged Al V and Al VI units initially. The second point could be correlated with a change in the oxidation state of one of the La-glass component. The reason why no similar paramagnetic center is created during irradiation for Ce-glass is not well understood but a possible charge trapping process involving Ce(III)/Ce(IV) is developed. Finally, leaching solution analysis indicated that normalized elemental releases are almost unchanged after irradiation for both of the La and Ce-glass. The globally weak influence of β irradiation on this family of glass is subsequent to the low mobility of the major components that form high field strength bonds with oxygen

  18. Complexation of amidocarbamoyl phosphine oxides with Ln{sup +3} (Ln = La, Nd, Pm, Sm and Eu) cation series: structural and thermodynamical features

    Energy Technology Data Exchange (ETDEWEB)

    Hosseinnejad, Tayebeh; Kazemi, Tayebeh [Alzahra Univ., Tehran (Iran, Islamic Republic of). Dept. of Chemistry

    2016-05-01

    In the present study, we have mainly investigated the nature of interactions in Ln{sup 3+} (Ln = La, Nd, Pm, Sm, Eu) complexes with amidocarbamoyl methyl phosphine oxide (CMPO) and amidocarbamoyl propyl phosphine oxide (CPPO) ligands based on density functional theory (DFT) approaches. In the first step, thermodynamical properties for complexation of CMPO and CPPO ligands with Ln{sup 3+} cation series have been determined in the gas phase and with the presence of three solvents: n-hexane, chloroform and toluene, via polarized continuum model (PCM) computations. The trend of metal-ligand interaction strength has been analyzed and compared with the trend of ionic hardness within the series of lanthanide cations and different size of alkyl chain of amidocarbamoyl phosphine oxide ligand. The calculated thermochemical results in the gas and solution phases reveals that there is a consistency between increasing trend in the hardness of Ln{sup 3+} cation series and also electron-donating property of alkyl chain with increasing in thermodynamical stability of [Ln-CMPO]{sup 3+} and [Ln-CPPO]{sup 3+} complex series. We have also demonstrated that in the complexation reaction of all complex series, using n-hexane as solvent is more favorable thermodynamically than chloroform and toluene. It should be stated that this issue has been observed in many experiments. Finally, analysis of calculated deformation energies and also the variation in bond order of some selected key bonds in CMPO and CPPO ligands and their corresponded Ln{sup 3+} complexes series show a similar trend with increasing in the hardness of Ln{sup 3+} cation series and electron-donating of alkyl chain of amidocarbamoyl phosphine oxide ligand.

  19. Complexation of amidocarbamoyl phosphine oxides with Ln+3 (Ln = La, Nd, Pm, Sm and Eu) cation series: structural and thermodynamical features

    International Nuclear Information System (INIS)

    Hosseinnejad, Tayebeh; Kazemi, Tayebeh

    2016-01-01

    In the present study, we have mainly investigated the nature of interactions in Ln 3+ (Ln = La, Nd, Pm, Sm, Eu) complexes with amidocarbamoyl methyl phosphine oxide (CMPO) and amidocarbamoyl propyl phosphine oxide (CPPO) ligands based on density functional theory (DFT) approaches. In the first step, thermodynamical properties for complexation of CMPO and CPPO ligands with Ln 3+ cation series have been determined in the gas phase and with the presence of three solvents: n-hexane, chloroform and toluene, via polarized continuum model (PCM) computations. The trend of metal-ligand interaction strength has been analyzed and compared with the trend of ionic hardness within the series of lanthanide cations and different size of alkyl chain of amidocarbamoyl phosphine oxide ligand. The calculated thermochemical results in the gas and solution phases reveals that there is a consistency between increasing trend in the hardness of Ln 3+ cation series and also electron-donating property of alkyl chain with increasing in thermodynamical stability of [Ln-CMPO] 3+ and [Ln-CPPO] 3+ complex series. We have also demonstrated that in the complexation reaction of all complex series, using n-hexane as solvent is more favorable thermodynamically than chloroform and toluene. It should be stated that this issue has been observed in many experiments. Finally, analysis of calculated deformation energies and also the variation in bond order of some selected key bonds in CMPO and CPPO ligands and their corresponded Ln 3+ complexes series show a similar trend with increasing in the hardness of Ln 3+ cation series and electron-donating of alkyl chain of amidocarbamoyl phosphine oxide ligand.

  20. Magnetic characterization of microcrystalline Na3Ln0.99–xEr0.01Crx(PO42 orthophosphates synthesized by Pechini method (Ln = La, Gd

    Directory of Open Access Journals (Sweden)

    Kaczmarek S.M.

    2018-03-01

    Full Text Available Na3Ln(PO42 orthophosphates (Ln = La, Gd doped with Er3+ and co-doped with Cr3+ ions were synthesized by Pechini method and characterized by electron paramagnetic resonance (EPR and magnetic susceptibility measurements. Low temperature EPR spectra were detected and analyzed in terms of temperature dependence and the structure of the obtained materials. They show that erbium and chromium ions substitute Ln3+ and also Na+ ions or Na+ channels forming complex EPR spectra. Both kinds of ions reveal ferromagnetic type of interaction which shows some anomaly at the temperature between 10 K and 15 K. Magnetic susceptibility reveals a weak antiferromagnetic kind of interaction dominating in the whole temperature range, from 3.5 to 300 K.

  1. Effects of Out-of-Plane Disorder on the Nodal Quasiparticle and Superconducting Gap in Single-Layer Bi_2Sr_1.6Ln_0.4CuO_6 delta (Ln = La, Nd, Gd)

    Energy Technology Data Exchange (ETDEWEB)

    Hashimoto, M.

    2011-01-04

    How out-of-plane disorder affects the electronic structure has been investigated for the single-layer cuprates Bi{sub 2}Sr{sub 1.6}Ln{sub 0.4}CuO{sub 6+{delta}} (Ln = La, Nd, Gd) by angle-resolved photoemission spectroscopy. We have observed that, with increasing disorder, while the Fermi surface shape and band dispersions are not affected, the quasi-particle width increases, the anti-nodal gap is enhanced and the superconducting gap in the nodal region is depressed. The results indicate that the superconductivity is significantly depressed by out-of-plane disorder through the enhancement of the anti-nodal gap and the depression of the superconducting gap in the nodal region.

  2. Synthesis and Structures of Two Lanthanide Complexes Containing a Mixed Ligand System: [Ln(Phen)2(L)3(HL)]·H2O [Ln = La, Ce; Phen = Phenanthroline; HL = Salicylic Acid

    International Nuclear Information System (INIS)

    Iravani, Effat; Nami, Navabeh; Nabizadeh, Fatemeh; Bayani, Elham; Neumueller, Bernhard

    2013-01-01

    The reaction of LnCl 3 ·7H 2 O [Ln = La (1), Ce (2)] with salicylic acid (HL) and 1,10-phenanthroline (Phen) at 20 .deg. C in H 2 O/ethanol gave after work-up and recrystallization two novel lanthanide complexes with general formula [Ln(Phen) 2 (L) 3 (HL)]·H 2 O. Compounds 1 and 2 were characterized by IR and UV-Vis spectroscopy, TGA, CHN as well as by X-ray analysis. According to these results, compounds 1 and 2 are isostructural and contain Ln 3+ ions with coordination number nine. Complexes 1 and 2 consist of two Phen, one neutral HL and three L anions (two L anions act as monodentate ligands and the third one is chelating to Ln 3+ ). Thermal decomposition led to primary loss of the Phen molecules. Then HL molecules and finally L moieties left the material to give Ln 2 O 3

  3. An anti CuO{sub 2}-type metal hydride square net structure in Ln{sub 2}M{sub 2}As{sub 2}H{sub x} (Ln = La or Sm, M = Ti, V, Cr, or Mn)

    Energy Technology Data Exchange (ETDEWEB)

    Mizoguchi, Hiroshi; Park, SangWon; Hosono, Hideo [Tokyo Institute of Technology, Yokohama (Japan). Materials Research Center for Element Strategy; Hiraka, Haruhiro; Ikeda, Kazutaka; Otomo, Toshiya [High-Energy Accelerator Research Organization (KEK), Tsukuba (Japan). Inst. of Materials Structure Science

    2015-03-02

    Using a high pressure technique and the strong donating nature of H{sup -}, a new series of tetragonal La{sub 2}Fe{sub 2}Se{sub 2}O{sub 3}-type layered mixed-anion arsenides, Ln{sub 2}M{sub 2}As{sub 2}H{sub x}, was synthesized (Ln=La or Sm, M=Ti, V, Cr, or Mn; x∼3). In these compounds, an unusual M{sub 2}H square net, which has anti CuO{sub 2} square net structures accompanying two As{sup 3-} ions, is sandwiched by (LaH){sub 2} fluorite layers. Notably, strong metal-metal bonding with a distance of 2.80 Aa was confirmed in La{sub 2}Ti{sub 2}As{sub 2}H{sub 2.3}, which has metallic properties. In fact, these compounds are situated near the boundary between salt-like ionic hydrides and transition-metal hydrides with metallic characters.

  4. An anti CuO{sub 2}-type metal hydride square net structure in Ln{sub 2}M{sub 2}As{sub 2}H{sub x} (Ln = La or Sm, M = Ti, V, Cr, or Mn)

    Energy Technology Data Exchange (ETDEWEB)

    Mizoguchi, Hiroshi; Park, SangWon; Hosono, Hideo [Materials Research Center for Element Strategy, Tokyo Institute of Technology, Yokohama 226-8503 (Japan); Hiraka, Haruhiro; Ikeda, Kazutaka; Otomo, Toshiya [Institute of Materials Structure Science, High-Energy Accelerator Research Organization (KEK), Tsukuba 305-0801 (Japan)

    2015-03-02

    Using a high pressure technique and the strong donating nature of H{sup -}, a new series of tetragonal La{sub 2}Fe{sub 2}Se{sub 2}O{sub 3}-type layered mixed-anion arsenides, Ln{sub 2}M{sub 2}As{sub 2}H{sub x}, was synthesized (Ln=La or Sm, M=Ti, V, Cr, or Mn; x∼3). In these compounds, an unusual M{sub 2}H square net, which has anti CuO{sub 2} square net structures accompanying two As{sup 3-} ions, is sandwiched by (LaH){sub 2} fluorite layers. Notably, strong metal-metal bonding with a distance of 2.80 Aa was confirmed in La{sub 2}Ti{sub 2}As{sub 2}H{sub 2.3}, which has metallic properties. In fact, these compounds are situated near the boundary between salt-like ionic hydrides and transition-metal hydrides with metallic characters. (copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  5. Synthesis and Structures of Two Lanthanide Complexes Containing a Mixed Ligand System: [Ln(Phen){sub 2}(L){sub 3}(HL)]·H{sub 2}O [Ln = La, Ce; Phen = Phenanthroline; HL = Salicylic Acid

    Energy Technology Data Exchange (ETDEWEB)

    Iravani, Effat [UNiv. of Applied Science and Technology, Tehran (Iran, Islamic Republic of); Nami, Navabeh; Nabizadeh, Fatemeh; Bayani, Elham [Islamic Azad Univ., Mazandaran (Iran, Islamic Republic of); Neumueller, Bernhard [Philipps-Universitat Marburg, Marburg (Germany)

    2013-11-15

    The reaction of LnCl{sub 3}·7H{sub 2}O [Ln = La (1), Ce (2)] with salicylic acid (HL) and 1,10-phenanthroline (Phen) at 20 .deg. C in H{sub 2}O/ethanol gave after work-up and recrystallization two novel lanthanide complexes with general formula [Ln(Phen){sub 2}(L){sub 3}(HL)]·H{sub 2}O. Compounds 1 and 2 were characterized by IR and UV-Vis spectroscopy, TGA, CHN as well as by X-ray analysis. According to these results, compounds 1 and 2 are isostructural and contain Ln{sup 3+} ions with coordination number nine. Complexes 1 and 2 consist of two Phen, one neutral HL and three L anions (two L anions act as monodentate ligands and the third one is chelating to Ln{sup 3+}). Thermal decomposition led to primary loss of the Phen molecules. Then HL molecules and finally L moieties left the material to give Ln{sub 2}O{sub 3}.

  6. Mixed ligand complexes of some of the rare earths. La(III)-, Pr(III)- or Nd-(III)-CDTA-Hydroxy Acids

    Energy Technology Data Exchange (ETDEWEB)

    Rana, H S; Tandon, J P [Rajasthan Univ., Jaipur (India). Chemical Labs.

    1975-11-01

    Biligand complexes of the 1:1 Ln(III)-1,2-diaminocyclohexane-tetraacetic acid (CDTA) chelate with hydroxy acids (where hydroxy acids = salicylic acid (SA); Sulphosalicylic acid (SSA) and 8-hydroxyquinoline-5-sulphonic acid (HQSA)) have been investigated by potentiometric titration. Their formation constants have been calculated (..mu..=0.1M-KNO/sub 3/; and t=30+-1 deg C) as 4.60 +-0.03, 5.46+-0.03, 5.87+-0.05; 3.12+-0.04, 3.95+-0.05, 4.42+-0.07; 2.73+-0.06, 3.45+-0.05 and 3.90+-0.08 for Ln(III)-CDTA-SA,-SSA, and -HQSA respectively (where Ln=La, Pr or Nd). The value of log Ksub(MAB) follows the order: La(III)<Pr(III)

  7. Synthesis and characterisation of the n = 2 Ruddlesden–Popper phases Ln{sub 2}Sr(Ba)Fe{sub 2}O{sub 7} (Ln = La, Nd, Eu)

    Energy Technology Data Exchange (ETDEWEB)

    Gurusinghe, Nicola N.M. [School of Chemistry, The University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom); Figuera, Juand de la; Marco, José F. [Instituto de Quimica-Fisica “Rocasolano”, CSIC, Serrano 119, 28006 Madrid (Spain); Thomas, Michael F. [Department of Physics, University of Liverpool, Liverpool. L69 3BX (United Kingdom); Berry, Frank J., E-mail: f.j.berry.1@bham.ac.uk [School of Chemistry, The University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom); Greaves, Colin [School of Chemistry, The University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom)

    2013-09-01

    Graphical abstract: - Highlights: • Some Ruddlesden–Popper phases have been characterised. • Substitution on the A site influences cationic order. • The magnetic moment redirects with temperature - Abstract: A series of n = 2 Ruddlesden–Popper phases A{sub 2}B{sub 2}O{sub 7} of composition Ln{sub 2}Sr(Ba)Fe{sub 2}O{sub 7} (Ln = La, Nd, Eu) have been prepared. La{sub 2}SrFe{sub 2}O{sub 7} and La{sub 2}BaFe{sub 2}O{sub 7} crystallise in the tetragonal space group I4/mmm. The structures of Eu{sub 2}SrFe{sub 2}O{sub 7} and Nd{sub 2}SrFe{sub 2}O{sub 7} are best described in space group P4{sub 2}/mnm. Substitution on the A site with smaller lanthanide- and larger alkaline metal- ions leads to enhanced cationic order in these phases and reflects increasing differences in cationic radii. All the compounds are antiferromagnetically ordered between 298 and 2 K. In La{sub 2}SrFe{sub 2}O{sub 7} the magnetic moment lies along [1 1 0] at all temperatures between 298 and 2 K whereas in La{sub 2}BaFe{sub 2}O{sub 7} the magnetic moment at 298 K lies along the crystallographic x-axis but redirects from the [1 0 0] to the [1 1 0] direction between 210 and 190 K and is retained in this direction until 2 K. In Nd{sub 2}SrFe{sub 2}O{sub 7} the magnetic moment at 298 K lies along [1 1 0] but rotates from [1 1 0] to [0 0 1] between 17 and 9 K. A series of {sup 57}Fe Mössbauer spectra recorded from La{sub 2}SrFe{sub 2}O{sub 7} between 290 and 600 K indicate a magnetic ordering temperature of T{sub N} ≥ 535 K.

  8. Synthesis and characterization of heterobinuclear (La-Zn, Pr-Zn, Nd-Zn, Sm-Zn, Eu-Zn, Gd-Zn, Tb-Zn, Dy-Zn) azine-bridged complexes

    International Nuclear Information System (INIS)

    Singh, Bachcha; Srivastav, A.K.; Singh, P.K.

    1997-01-01

    Zinc(II) complex of 2-acetylpyridine salicyl aldazine (Haps) of the type Zn(aps) 2 (H 2 O) 2 has been synthesised. The reaction of Zn(aps) 2 (H 2 O) 2 with lanthanide chlorides, LnCl 3 (where Ln=La, Pr, Nd, Sm, Eu, Gd, Tb and Dy) yields azine-bridged heterobinuclear complexes of the formulae LnCl 3 Zn(aps) 2 (H 2 O) 2 . These complexes have been characterized by elemental analyses, molecular weight, conductance (solid and solution) and magnetic susceptibility measurements, mass, IR and electronic spectral data. X-ray powder diffraction data indicate the tetragonal unit lattice for Zn(aps) 2 (H 2 O) 2 and PrCl 3 Zn(aps) 2 (H 2 O) 2 . (author)

  9. Determinación del coeficiente piroeléctrico del sistema ferroeléctrico cerámico de Pb0.88Ln0.08Ti0.98Mn0.02O3 (Ln=La, Sm, Eu y su aplicación en detectores de infrarrojo

    Directory of Open Access Journals (Sweden)

    Suaste-Gómez, E.

    2004-12-01

    Full Text Available In this work the dielectric and pyroelectric characteristics of the ferroelectric ceramic system of Pb0.88(Ln0.08Ti0.98Mn0.02O3 (Ln = La, Sm, Eu are studied in order to determine its usefulness as infrared dectectors. Dielectric constant and pyroelectric coefficient of the ceramics were determined. This material with perovskite structure presented a phase transition from tetragonal to cubic on the heating process, besides of presenting high values of dielectric constant. Values of figure of merit for infrared detection Rv=pi/εr were calculated. The results were compared with other materials used as infrared detectors.En este trabajo se estudian las características dieléctricas y piroeléctricas del sistema ferroléctrico cerámico de Pb0.88(Ln0.08Ti0.98 Mn0.02O3 (Ln = La, Sm, Eu para determinar su utilidad como detectores de infrarrojo. Se determinó la constante dieléctrica y el coeficiente piroeléctrico de las cerámicas. Este material con estructura de perovskita presentó una transición de fase tetragonal a cúbica en el proceso de calentamiento, además de presentar altos valores de la constante dieléctrica. Se obtuvieron valores de la figura de mérito para detección infrarroja Rv=pi/εr Los resultados se compararon con otros materiales usados como detectores de infrarrojo.

  10. X-ray photoelectron spectroscopic study of direct reforming catalysts Ln{sub 0.5}Sr{sub 0.5}Ti{sub 0.5}Mn{sub 0.5}O{sub 3±d} (Ln = La, Nd, and Sm) for high temperature-operating solid oxide fuel cell

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Keunsoo [Department of Engine Research, Korea Institute of Machinery and Materials, 156 Gajeongbuk-Ro, Daejeon 305-343 (Korea, Republic of); Jeong, Jihoon [Department of Mechanical Engineering, The University of Texas at Austin, Austin, TX 78712 (United States); Azad, Abul K. [Faculty of Integrated Technologies, University Brunei Darussalam, Jalan Tunku Link, Gadong BE1410 (Brunei Darussalam); Jin, Sang Beom [Department of Advanced Materials Science and Engineering, Hanbat National University, 125, Dongseo-Daero, Yusung-Gu, Daejeon 305-719 (Korea, Republic of); Kim, Jung Hyun, E-mail: jhkim2011@hanbat.ac.kr [Department of Advanced Materials Science and Engineering, Hanbat National University, 125, Dongseo-Daero, Yusung-Gu, Daejeon 305-719 (Korea, Republic of)

    2016-03-01

    Graphical abstract: Measured Ti 2p peaks and deconvolution peaks of Nd{sub 0.5}Sr{sub 0.5}Ti{sub 0.5}Mn{sub 0.5}O{sub 3±d} under oxidizing condition (left) and NSTM under reducing condition (right). - Highlights: • Chemical states of Ln{sub 0.5}Sr{sub 0.5}Ti{sub 0.5}Mn{sub 0.5}O{sub 3±d} (Ln: La, Nd and Sm) were analyzed. • Charge compensation occurred with the reduction of Mn and Ti. • The Nd substitution effect allowed some Ti to convert into a metallic behavioral component. • NSTM and SSTM had a large amount of lattice oxygen; however, LSTM retained a large quantity of adsorbed oxygen. - Abstract: Chemical states of lanthanide doped perovskite for direct reforming anode catalysts, Ln{sub 0.5}Sr{sub 0.5}Ti{sub 0.5}Mn{sub 0.5}O{sub 3±d} (Ln = La, Nd, and Sm) have been studied by X-ray Photoelectron Spectroscopy (XPS) in order to determine the effects of various lanthanide substitution in complex perovskites for high temperature-operating solid oxide fuel cells (HT-SOFC). The charge state of lanthanide ions remained at 3+ and the binding energies of the lanthanide ions in Ln{sub 0.5}Sr{sub 0.5}Ti{sub 0.5}Mn{sub 0.5}O{sub 3±d} were located in a relatively lower range compared to those of conventional lanthanide oxides. Mn and Ti were regarded as charge compensation components in Ln{sub 0.5}Sr{sub 0.5}Ti{sub 0.5}Mn{sub 0.5}O{sub 3±d}; Mn was more influential than Ti. In the cases of substituting Nd and Sm into Ln{sub 0.5}Sr{sub 0.5}Ti{sub 0.5}Mn{sub 0.5}O{sub 3±d}, some portion of Ti showed metallic behavior; the specific Mn satellite peak indicating an electro-catalytic effect had occurred. Three types of oxygen species comprised of lattice oxygen, carbonate species, and adsorbed oxygen species were observed in Ln{sub 0.5}Sr{sub 0.5}Ti{sub 0.5}Mn{sub 0.5}O{sub 3±d} from the O 1s spectra; a high portion of lattice oxygen was observed in both Nd{sub 0.5}Sr{sub 0.5}Ti{sub 0.5}Mn{sub 0.5}O{sub 3±d} (NSTM) and Sm{sub 0.5}Sr{sub 0.5}Ti{sub 0.5}Mn{sub 0.5}O

  11. Synthesis and magneto-structural studies on a new family of carbonato bridged 3d-4f complexes featuring a [CoLn(CO3)] (Ln = La, Gd, Tb, Dy and Ho) core: slow magnetic relaxation displayed by the cobalt(ii)-dysprosium(iii) analogue.

    Science.gov (United States)

    Majee, Mithun Chandra; Towsif Abtab, Sk Md; Mondal, Dhrubajyoti; Maity, Manoranjan; Weselski, Marek; Witwicki, Maciej; Bieńko, Alina; Antkowiak, Michał; Kamieniarz, Grzegorz; Chaudhury, Muktimoy

    2018-03-06

    A new family of [3 + 3] hexanuclear 3d-4f complexes [(μ 3 -CO 3 ){Co II Ln III L(μ 3 -OH)(OH 2 )} 3 ]-(ClO 4 )·mC 2 H 5 OH·nH 2 O (1-5) [Ln = La (1), Gd (2), Tb (3), Dy (4), and Ho (5)] have been prepared in moderate to high yields (62-78%) following a self-assembly reaction between the ligand 6,6',6''-(nitrilotris(methylene))tris-(2-methoxy-4-methylphenol) (H 3 L), Co(OAc) 2 ·4H 2 O and the lanthanide ion precursors in the mandatory presence of tetrabutylammonium hydroxide. During the reaction, atmospheric carbon dioxide is fixed in the product molecule as a bridging carbonato ligand which connects all the three lanthanide centers of this molecular assembly through a rare η 2 :η 2 :η 2 -μ 3 mode of bridging as revealed from X-ray crystallography. The metal centers in all these compounds, except the Gd III analogue (2), are coupled in antiferromagnetic manner while the nature of coupling in the CoGd complex is ferromagnetic. DFT calculations revealed that this ferromagnetic interaction occurs most likely by the Co II -Gd III superexchange, mediated via the bridging oxygen atoms. Only the Co II -Dy III compound (4) displayed a slow relaxation of the magnetization at a very low temperature as established by AC susceptibility measurements. The data provides an estimation of the activation energy U/k B = 9.2 K and the relaxation time constant τ 0 = 1.0 × 10 -7 s.

  12. Magnetic properties of cyano-bridged Ln3+-M3+ complexes. Part I: trinuclear complexes (Ln3+ = La, Ce, Pr, Nd, Sm; M3+ = FeLS, Co) with bpy as blocking ligand.

    Science.gov (United States)

    Figuerola, Albert; Ribas, Joan; Llunell, Miquel; Casanova, David; Maestro, Miguel; Alvarez, Santiago; Diaz, Carmen

    2005-10-03

    The reaction of Ln(NO3)3(aq) with K3[Fe(CN)6] or K3[Co(CN)6] and 2,2'-bipyridine in water/ethanol led to eight trinuclear complexes: trans-[M(CN)4(mu-CN)2{Ln(H2O)4(bpy)2}2][M(CN)6].8H2O (M = Fe3+ or Co3+, Ln = La3+, Ce3+, Pr3+, Nd3+, and Sm3+). The structures for the eight complexes [La2Fe] (1), [Ce2Fe] (2), [Pr2Fe] (3), [Nd2Fe] (4), [Ce2Co] (5), [Pr2Co] (6), [Nd2Co] (7), and [Sm2Co] (8) have been solved; they crystallize in the triclinic space group P and are isomorphous. They exhibit a supramolecular 3D architecture through hydrogen bonding and pi-pi stacking interactions. A stereochemical study of the nine-vertex polyhedra of the lanthanide ions, based on continuous shape measures, is presented. No significant magnetic interaction was found between the lanthanide(III) and the iron(III) ions.

  13. Investigation of phase relationships in subsolidus region of Ln2O3-MoO3-B2O3 systems

    International Nuclear Information System (INIS)

    Lysanova, C.V.; Dzhurinskij, B.F.; Komova, M.G.; Tananaev, I.V.

    1983-01-01

    Phase formation in subsolidus region of Ln 2 O 3 -MoO 3 B 2 O 3 systems (Ln-La, Nd) is studied. Three compounds with mixed oxyanions-boratomolybdates of LnMoBO 6 composition (Ln-La, Ce, Pr, Nd), Ln 2 MoB 2 O 9 (Ln-La, Ce, Pr, Nd, Sm, EU, Gde Tb) Ln 6 Mo 3 B 4 0 24 (Ln-Pr, Nd) are revealed and described

  14. 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.

  15. 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...

  16. PR, Lobbyism and Democracy

    DEFF Research Database (Denmark)

    Ørsten, Mark; Willig, Ida; Pedersen, Leif Hemming

    2017-01-01

    The growth of PR in Scandinavia is linked both to the mediatization of politics and to the decline of corporatism. Studies in Sweden and Norway suggest that one consequence of these changes is the increasing number of politicians who find new careers as lobbyists in the private sector. In this st......The growth of PR in Scandinavia is linked both to the mediatization of politics and to the decline of corporatism. Studies in Sweden and Norway suggest that one consequence of these changes is the increasing number of politicians who find new careers as lobbyists in the private sector....... Still, 89 percent of all the registered job positions fall outside of lobbyism. 11 percent of the job positions fall within the wider field associated with the emerging field of policy professionals (including lobbyism), while lobbyism on its own accounts for 2 percent of the job positions....

  17. Préface

    Science.gov (United States)

    Chardonnet, Christian; Millot, Guy

    2006-10-01

    COLOQ, réunion nationale biennale initiée en 1988 par la communauté française des lasers, de l'optique non linéaire et de l'optique quantique atteint sa neuvième édition. Depuis sa création, les objectifs poursuivis sont les suivants : - réunir la communauté française des lasers, de l'optique non linéaire et de l'optique quantique, en dépassant les clivages fondamental/appliqué, recherche publique/industrielle, - faire le point sur les avancées récentes, - permettre aux jeunes chercheurs de se rencontrer, de s'exprimer et de s'aguerrir au plan national. Le but est que tout thésard du domaine de l'optique puisse participer à COLOQ une fois durant sa thèse, présenter son travail et de se confronter à la communauté de l'optique. COLOQ9 s'est tenu, pour sa 9e édition, sur le campus universitaire de Dijon, du 7 au 9 septembre 2005. Il a été une grande réussite : nombre de participants (255) et de présentations scientifiques record (148 affiches), forte représentation des industriels (15) et participation d'environ 200 lycéens aux conférences grand public. Le nombre plus élevé que prévu d'affiches a rendu un peu serrée leur présentation : une attention particulière sera portée à cet aspect lors des prochaines éditions. Ces journées ont été consacrées à des conférences invitées données par des scientifiques de haut niveau et à des présentations sous forme d'affiches. Une plage de temps importante a été réservée pour des discussions autour des affiches. À proximité immédiate de la salle de conférence, l'exposition de matériels spécialisés pour les lasers, l'optique et l'optoélectronique a été une occasion pour les jeunes participants de découvrir et contacter les industriels et les autres grands acteurs de l'optique. L'année 2005 ayant été l'année mondiale de la physique, COLOQ9 a retenu comme thème central ”1905-2005 : à propos d'Einstein". Plusieurs grandes conférences ont été dédiées à ce th

  18. Présentation

    Directory of Open Access Journals (Sweden)

    Stéphane Haber

    2010-08-01

    Full Text Available Les articles réunis dans ce dossier de la revue Astérion portent sur la première génération de la Théorie critique (dont Max Horkheimer, Walter Benjamin, Theodor W. Adorno, Herbert Marcuse et Erich Fromm constituent sans doute les figures principales. Ils se concentrent plus précisément sur les contributions philosophiques qui marquèrent la période ouverte par l’accession de Horkheimer à la direction de l’Institut de recherches sociales (1931 et close par la publication en 1944 de Dialektik...

  19. 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

  20. STRATEGIJSKA ULOGA PR U SPORTU

    Directory of Open Access Journals (Sweden)

    Duško Tomić

    2005-05-01

    Full Text Available PR in the modern world are developed with rapid speed and become important aspect of strategic management. Modern menagers are very interesting in PR and they observe that there is not successful strategy without experiance theory and practice in PR. The goals must be defined, basic phylosophy to, and managers must take responsability and describe everithing what they have to do. It must be financial fond and evaluation must be done

  1. Préface

    Directory of Open Access Journals (Sweden)

    Sylvie Duvillard

    2010-09-01

    Full Text Available Le moment est opportun, la question foncière est de retour, légitimée par presque une décennie (2001-2008 d’augmentation continue des prix de l’immobilier. De « sommets » , en articles de presse, la montagne et les Alpes en particulier font l’objet, dans ce domaine, d’une attention toute particulière. Le contexte est ici délicat. Les sociétés alpines sont partagées entre désir de préservation d’une forte identité montagnarde et crainte d’une « déprise » économique (agricole, touristique et/...

  2. Présentation

    Directory of Open Access Journals (Sweden)

    Frédéric Hitzel

    2009-05-01

    Full Text Available « À ma connaissance, il n'est pas de compagnon plus fidèle à ses engagements, plus prompt à honorer les faveurs reçues, plus empressé à offrir ses services, et ce à moindre frais, que le livre. Je ne connais aucun arbre qui ait un fruit plus succulent, plus précoce, plus aisé à cueillir, plus disponible à tout moment, comme le livre. Je ne sais pas de produit qui, malgré son jeune âge et la proximité de sa naissance, la facilité avec laquelle on peut se le procurer, la modicité de son prix, a...

  3. Présentation

    Directory of Open Access Journals (Sweden)

    Agnès Bouvier

    2012-02-01

    Full Text Available Le 7 juin 1844, Flaubert écrit à Louis de Cormenin : « J’ai lu Candide vingt fois, je l’ai traduit en anglais et je l’ai encore relu de temps à autre. » Quel que soit le degré de sérieux de cette affirmation, elle témoigne d’un intérêt précoce de Flaubert pour l’acte de traduire. De même, l’écrivain attachait de l’importance aux traductions qu’il lisait : « Je relis maintenant Don Quichotte dans la nouvelle traduction de Damas Hinard » écrit-il à Louise Colet en novembre 1847. Il lui arrivait...

  4. Présentation

    Directory of Open Access Journals (Sweden)

    Aurore Monod Becquelin

    2010-09-01

    Full Text Available Les recherches présentées dans ce volume sont issues des travaux de chercheurs qui se réunissent régulièrement depuis 2005 sur le thème de l’« Agentivité ». Ce groupe rassemble des ethnologues et des linguistes du Laboratoire d’ethnologie et de sociologie comparative (umr 7186, cnrs/université Paris Ouest Nanterre La Défense, du Laboratoire d’anthropologie sociale (umr 7130, Collège de France/ehess Paris/cnrs, de l’École des hautes études en sciences sociales, de l’Institut des hautes étude...

  5. 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.

  6. The PR Officer's Survival Kit.

    Science.gov (United States)

    Woodrum, Robert L.

    1996-01-01

    A former corporate public relations (PR) professional shares strategies for communicating and cooperating with the chief executive officer, and particularly for coping with differences in perceptions of the public relations officer's role. Basic attributes of a successful PR professional are outlined: good communication skills, an analytical…

  7. PR's involvement in International Cooperation

    NARCIS (Netherlands)

    Anonymous,

    1995-01-01

    In The Netherlands, the Research Station for Cattle, Sheep and Horse Husbandry (in Dutch abbreviated as PR) bridges the gap between more basic and disciplinary research done at universities and research institutes on the one hand and the extension service and the farmers on the other hand. The PR

  8. Prólogo

    Directory of Open Access Journals (Sweden)

    Alta Hooker

    2013-02-01

    Full Text Available Este volumen No. 11 presenta una compilación estructurada en 6 secciones temáticas las cuales comprenden 9 artículos. La primera sección en Educación, presenta los artículos: Métodos de enseñanza de Física en la modalidad a distancia en el instituto sabatino “Esperanza”,en el municipio de Siuna; y, Comportamiento disciplinario en la escuela “Niño Jesús”, Siuna, Región Autónoma Atlántico Norte, 2011. La segunda sección, titulada Educación Superior en la Costa Caribe Nicaragüense presenta los artículos: Formación de los docentes de la URACCAN en el Área de Recursos Naturales; asimismo, Pertinencia de los programas para el aprendizaje del inglés en Administración de Empresas, Recinto Nueva Guinea y Prácticas de campo en la formación de estudiantes de Ingeniería en Zootecnia, URACCAN Nueva Guinea. La tercera sección denominada Revitalización Lingüística y Cultural comprende dos artículos: Etno-matemática en indígenas ulwas, comunidad de Karawala, Región Autónoma Atlántico Sur, Nicaragua y Ma-Kuagro: Elementos de la cultura de San Basilio Palenque, Colombia, y su incidencia en las prácticas pedagógicas. La cuarta sección Cultura Indígena y Afrodescendiente comprende un artículo: Economía indígena en la comunidad de Wasakín, municipio de Rosita, RAAN. Clausura la quinta sección denominada Ciencias Sociales, el artículo La república Bolivariana de Venezuela y Nicaragua, en el marco del acuerdo energético.

  9. Préface

    Science.gov (United States)

    Aspect, Alain

    2004-11-01

    COLOQ est une conférence regroupant, tous les deux ans, la communauté scientifique et industrielle nationale travaillant dans les domaines des lasers, de l'optique non-linéaire et de l'optique quantique. Elle s'est tenue pour sa huitième édition à Toulouse, du 3 au 5 septembre 2004, sur le campus de I'INSA. Comme il est de tradition tous les quatre ans, COLOQ était couplé avec Horizons de l'optique, avec en particulier une journée commune dont le programme avait été préparé en concertation par les deux comités scientifiques. Depuis sa création, COLOQ a pour but de favoriser les rencontres entre les chercheurs des différents laboratoires nationaux publics ou privés travaillant sur les lasers et l'optique quantique au sens large. C'est un moyen privilégié de resserrer les liens de cette communauté et d'y intégrer les jeunes chercheurs. Ces derniers y trouvent l'occasion de se connaître, de se faire connaître, de découvrir la communauté à laquelle ils appartiennent et d'élargir leurs connaissances des thèmes qui la structurent. La participation de 230 chercheurs et d'une vingtaine d'exposants de matériels spécialisés dans les lasers et l'optoélectronique témoigne de la vitalité de COLOQ et de son audience dans les laboratoires et chez les industriels de l'optique. Le programme de COLOQ 8 comportait d'une vingtaine de conférences générales données par des chercheurs de renom international, et des séances de communications par affiches, occasions privilégiées de rencontres et d'échanges. Les exposés ont porté sur des sujets particulièrement actifs au niveau national et international, avec un accent sur des thèmes importants pour la région toulousaine : contrôle cohérent, optique et nanosciences, optique et astronomie, sans oublier la traditionnelle rubrique phénomènes fondamentaux, éclectique pour ne pas dire hétéroclite, mais si représentative d'une des ambitions de COLOQ qui est d'offrir à ses participants une

  10. Préface

    Science.gov (United States)

    Ouerdane, Youcef; Laporte, Pierre

    2005-06-01

    L'objectif de la série de colloques UVX est de réunir, au rythme d'une fois tous les deux ans, les scientifiques et industriels travaillant dans le domaine du développement des sources de photon de grande énergie (UV, VUV, et X) et de leurs applications. En particulier cette manifestation est l'occasion de faire se rencontrer une communauté très pluridisciplinaire (physique, chimie, biologie, sciences de l'univers) liée à des domaines en forte évolution technologique (lasers et rayonnement synchrotron notamment). Le colloque UVX 2004 s'est tenu au Palais des Congrès de Saint-Étienne (42000) du 7 au 11 juin 2004. La période écoulée depuis l'édition précédente (Oléron 2002) a été particulièrement active dans tous les domaines concernés : grands projets de sources, méthodes de diagnostic au sens large. Une nouvelle fois on constate que le bref et l'ultra-bref ont une place privilégiée, qu'il s'agisse du travail sur les accélérateurs ou sur les lasers qui, bien sûr, dans la course aux temps courts remportent la palme avec la présence de spécialistes du domaine attoseconde. La communauté représentée a la chance d'être en prise directe avec de très grands projets en phase active de réalisation comme le Laser Megajoule (LMJ), la source SOLEIL, et un projet d'ampleur plus modeste mais remarquable dans son domaine : la source LASERIX d'Orsay/Palaiseau. On pourra citer aussi le projet Arc en Ciel qui, lui, est encore au stade de sa définition. - SOLEIL, source de nouvelle génération de rayonnement synchrotron (plateau de Saclay) est dans une phase active de réalisation : achèvement de l'infrastructure en 2005 et injection du 1o faisceau dans l'anneau de stockage prévu également en 2005. Cette source devrait être la meilleure au monde dans le domaine VUV/X mous, tout en restant très polyvalente (brillance, accordabilité, structure temporelle, polarisation) et complémentaire de l'ESRF. Au final on disposera de 21 lignes de lumi

  11. ESO PR Highlights in 2006

    Science.gov (United States)

    2007-01-01

    Last year proved to be another exceptional year for the European organisation for ground-based astronomy. ESO should begin the New Year with two new member states: Spain (PR 05/06) and the Czech Republic (PR 52/06). ESO PR Highlights 2006 2006 was a year of renovation and revolution in the world of planets. A new Earth-like exoplanet has been discovered (PR 03/06) using a network of telescopes from all over the world (including the Danish 1.54-m one at ESO La Silla). It is not the only child of this fruitful year: thanks to the combined use of ESO's Very Large Telescope (VLT) and La Silla instruments, a surprising system of twin giant exoplanets was found (PR 29/06), and a trio of Neptune-like planets hosted by a nearby star were identified (PR 18/06). These results open new perspectives on the search for habitable zones and on the understanding of the mechanism of planet formation. The VISIR instrument on the VLT has been providing unique information to answer this last question, by supplying a high resolution view of a planet-forming disc (PR 36/06). There are not only new members in the planets' register: during the General Assembly of the International Astronomical Union held in Prague (Czech Republic), it was decided that Pluto is not a planet anymore but a 'dwarf planet'. Whatever its status, Pluto still has a satellite, Charon, whose radius and density have been measured more accurately by observing a rare occultation from different sites, including Cerro Paranal (PR 02/06). The scientific community dedicated 2006 to the great physicist James Clerk Maxwell (it was the 175th anniversary of the birth): without his electromagnetic theory of light, none of the astonishing discoveries of modern physics could have been achieved. Nowadays we can look at distant galaxies in great detail: the GIRAFFE spectrograph on the VLT revealed that galaxies 6 billion years ago had the same amount of dark matter relative to stars than nowadays (PR 10/06), while SINFONI gave an

  12. Préface

    Science.gov (United States)

    Hamieh, Tayssir

    2005-05-01

    Né simultanément à Mulhouse et à Beyrouth en 1996 dans le cadre d'une collaboraiion franco-libanaise sur une initiative personnelle de Monsieur Tayssir HAMIEH. le Colloque Franco-Libanais sur la Science des Matériaux (CSM), qui s'inscrit dans le cadre des relations étroites entre la France et le Liban, est très vite devenu une occasion très importante de rencontre entre scientifiques de haut niveau, non seulement, du contour méditerranéen mais également des pays européens, américains et arabes. La quatrieme édition CSM4 est une véritable réussite grâce à la participation des chercheurs confirmés dans tous les domaines des sciences de matériaux et venant de plusieurs pays tels que la France, I'Algérie, Le Liban, la Syrie, le Maroc, la Tunisie, l'Italie, l'Espagne, le Portugal, le Royaume Uni, les États-Unis, la Russie, l'Allemagne, le Japon et I'Inde ; pour présenter plus de 350 communications orales et par affiche et couvrant presque toutes les disciplines des systèmes des matériaux. Le choix des diffèrents thèmes du colloque sur la science des matériaux a été dicté par l'importance capitale de cette discipline dans notre civilisation moderne. En fait, les matériaux utilisés pour la fabrication artisanale ou industrielle d'objets, de produits et de systèmes ainsi que pour la réalisation de constructions et d'équipements ont de tout temps défini le niveau de notre civilisation technique. La réalisation des objectifs communs de notre monde en plein développement, pour ne pas dire en pleine mutation, est en grande partie tributaire de la mise au point de nouveaux matériaux et de procédés de transformation et d'assemblages nouveaux, présentant des performances et des qualités améliorées. Le colloque a illustré et traduit, de manière remarquables, l'excellente collaboration entre chercheurs libanais et français. Le partenariat est exemplaire par la qualité des laboratoires impliqués et par le niveau scientifique des r

  13. Political PR is dying. Long live business PR! / Ilyn Oleg

    Index Scriptorium Estoniae

    Oleg, Ilyn

    2005-01-01

    Vene suurima suhtekorraldusagentuuri Imageland Public Relations rahvusvaheliste suhete juhi hinnangul on Venemaal peamisteks probleemideks PR professionaalide vähesus, nende kehv haritus oma erialal, samuti vähene teadlikkus suhtekorralduse tähtsusest äris

  14. Erfolgsfaktoren unternehmerischer Krisen-PR

    OpenAIRE

    Scharr, Florian

    2006-01-01

    Ob "Peanuts", "Elchtest" oder "Hoechst-Störfall" - bei diesen bekannten Öffentlichkeitskrisen der letzten Jahre rief die mangelhafte Krisen-PR der betroffenen Unternehmen bei Medien und Bevölkerung mehr Empörung hervor als die originären Auslöser und potenzierte so den entstandenen Vertrauensverlust. Auch die sich gerade erst entwickelnde PR-Forschung bietet noch keine konkrete Hilfestellung zur Gestaltung von Krisen-PR. Mit dem bedeutenden Diskurs- und dadurch Realitätsgestaltungsmittel Pres...

  15. Présentation

    Directory of Open Access Journals (Sweden)

    Gregor Perko

    2011-12-01

    Full Text Available Au cours des dernières décennies où l’on assiste à une refondation de la morphologie, la discipline s’intéresse de plus en plus à des phénomènes « périphériques », « marginaux », « irréguliers » ou « extragrammaticaux », à des phénomènes n’appartenant pas aux « régions nodales » de la morphologie. Le présent numéro de Linguistica, premier numéro thématique de notre revue, réunit des études qui s’intéres- sent aux frontières internes et externes de la morphologie. La diversité et la richesse des thèmes abordés et des approches proposées témoignent d’un intérêt croissant que les linguistes, non pas uniquement les morphologues, portent à cette thématique. Les articles proposés s’articulent autour de cinq axes majeurs. Un premier axe rassemble les articles qui étudient les frontières entre différentes composantes de la morphologie. L’étude de Michel Roché examine les contraintes lexicales et morphophonologiques sur le paradigme des dérivés en –aie. Les résultats de son analyse remettent en question la notion de « règle de construction des lexèmes ». Irena Stramljič Breznik et Ines Voršič se penchent sur les néologismes de sport en slovène et essaient d’évaluer la productivité ou la créativité des procédés morphologiques en jeu. Dans une étude d’inspiration cognitiviste, Alexandra Bagasheva aborde l’hétérogénéité des verbes composés en anglais. En s’appuyant sur les données fournies par les para- digmes verbaux du maltais, Maris Camilleri examine la complexité du phénomène de classes flexionnelles basées sur les radicaux. Trois travaux concernent des procédés typiquement « extragrammaticaux » servant à former le plus souvent des occasionnalismes: Arnaud Léturgie tente de dégager des propriétés prototypiques de l’amalgamation lexicale en français, notamment celles de la création des mots-valises; Silvia Cacchiani analyse, à l

  16. 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

  17. 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

  18. Prácticas curriculares

    OpenAIRE

    García-Gordillo, Mar; Checa Godoy, Antonio; Gómez Mompart, Josep Lluis (Coordinador); Herrero Subías, Mónica (Coordinador)

    2015-01-01

    Esta ponencia pretende analizar, sucintamente, la situacion presente de las prácticas externas en las facultades de Comunicacion españolas. En una coyuntura sumamente peculiar, no solo para las prácticas de los titulos de Comunicacion, sino para todas las practicas universitarias, por los numerosos y a veces contradictorios cambios acaecidos en la legislacion reciente y los vaivenes normativos de las universidades; por la profunda crisis que viene atravesando el sector de la...

  19. Internet innovation in PR management

    Directory of Open Access Journals (Sweden)

    Ćalasan Veljko B.

    2014-01-01

    Full Text Available PR Management in the last decade has evolved to unimaginable limits . Its rapid 'evolution ' is directly linked to the development and innovation, above all, of internet communications - Cyber 'world'. Although the genesis of PR management was announced in a way, the changes of the modern PR management have led to a change in the general attitude towards this particular activity. It has become an indispensable factor for the success of every business or social enterprise. In the general run for internet contents with better quality, as an indispensable tool of PR management , for better use of cyberspace , a new generation of PR manager is created, who has almost no resemblance to the earlier managers before two decades. For these reasons, we believe that Internet innovation through the implementation of PR management, changed the world economy and society. Adjusting speed to this, virtual , yet very real world , is proportional to the speed of development of an economic system as a whole, or any company at the micro level , and society in general .Internet is not an important innovation itself to be sufficient to meet the form and define the essence of economic relations. Only its proper exploitation with the constant use of tested and more intense innovation is the only way to the overall success . The absence of the above, in our opinion, is a sure path to failure.

  20. PR Crisis Melalui Media Sosial

    Directory of Open Access Journals (Sweden)

    Gladys Carlina

    2017-07-01

    Full Text Available The background of this research is communication, new media, PR and PR Crisis. Fourth of this background has a close relationship, starting from communication, human in everyday life would require communication to receive and convey information, human can not be released from human life. The advancement of the times and the development of technology, causing people to communicate easily and the development of this era caused a new challenge for the PR and PR Crisis of a company, they should be able to maintain a positive image of the company in the minds of people. In this study using descriptive qualitative methodology, it contains many writings and drawings compared to the numbers. The purpose of this research is to know the strategy used by Pizza Hut in dealing with the issue of expired food. Penelitin results, social media is very positive impact on Pizza Hut in the recovery of food issues expired. The strategy used by the Pizza Hut Crisis PR is to utilize social media. Visible from the issue of expired food that disappeared in public and Pizza Hut restaurant until now crowded visited. Latar belakang dari penelitian ini yaitu komunikasi, media baru, PR dan PR Krisis. Keempat dari latar belakang ini mempunyai hubungan yang erat, dimulai dari komunikasi, manusia di dalam kehidupan sehari-hari tentunya memerlukan komunikasi untuk menerima dan menyampaikan informasi, manusia tidak bisa dilepaskan dari kehidupan manusia. Majunya perkembangan zaman dan perkembangan teknologi, menyebabkan manusia melakukan komunikasi dengan mudah dan perkembangan zaman ini menyebabkan adanya tantangan baru bagi para PR dan PR Krisis sebuah perusahaan, mereka harus bisa mempertahankan citra positif perusahaan di benak masyarakat. Dalam penelitian ini menggunakan metodologi kualitatif deksriptif, memuat banyak tulisan dan gambar dibandingkan angka-angka. Tujuan dari penelitian ini untuk mengetahui strategi yang digunakan oleh Pizza Hut dalam menangani isu makanan

  1. Development of electrolyte-supported intermediate-temperature single-chamber solid oxide fuel cells using Ln{sub 0.7}Sr{sub 0.3}Fe{sub 0.8}Co{sub 0.2}O{sub 3-{delta}} (Ln = Pr, La, Gd) cathodes

    Energy Technology Data Exchange (ETDEWEB)

    Ruiz de Larramendi, I.; Ruiz de Larramendi, J.I.; Rojo, T. [Departamento de Quimica Inorganica, Universidad del Pais Vasco, Apdo.644, 48080 Bilbao (Spain); Lamas, D.G.; Cabezas, M.D.; Walsoee de Reca, N.E. [CINSO, CONICET-CITEFA, J.B. de La Salle 4397 (B1603ALO) Villa Martelli, Pcia. de Buenos Aires (Argentina)

    2009-09-05

    Iron-cobalt-based perovskite oxides with general formula Ln{sub 0.7}Sr{sub 0.3}Fe{sub 0.8}Co{sub 0.2}O{sub 3-{delta}} (where Ln = La, Pr and Gd) have been investigated for their application as intermediate-temperature cathodes in solid oxide fuel cells (SOFCs). Powdered samples of these materials were synthesized by a novel gel combustion process and then characterized by X-ray powder diffraction (XPD) and scanning electron microscopy (SEM). XPD patterns were satisfactorily indexed with an orthorhombic GdFeO{sub 3}-type structure and, for all samples, a mean particle size of less than 1 {mu}m was estimated from the SEM data. Experimental single-chamber SOFCs using with these materials as cathodes and NiO-SDC (samaria-doped ceria) and SDC as anode and electrolyte, respectively, were evaluated at 600 C in a methane/oxygen mixtures. Peak power densities of 65.4, 48.7 and 46.2 mW cm{sup -2} were obtained for Ag vertical stroke Ln{sub 0.7}Sr{sub 0.3}Fe{sub 0.8}Co{sub 0.2}O{sub 3-{delta}} vertical stroke SDC vertical stroke NiO-SDC vertical stroke Pt cells with Ln = Pr, La and Gd, respectively. The relatively high power density obtained for the Pr compound shows that it could be an interesting material for cathode of single-chamber SOFCs. (author)

  2. Ten years experience of PR

    International Nuclear Information System (INIS)

    Dobak, Dobroslav

    2002-01-01

    This paper is an effort to summarize the way Slovak Bohunice NPP has gone through since the historical change in the Middle and Eastern European countries. Milestones on the way were: 1989 - change of political system; increasing interest of the public appearance; creation of work capacities - personnel and technical; education/exchange with Western countries; 1994 - establishment of Foreign Affairs and PR Department reporting directly to the NPP manager; application of various approaches, some observed from other countries; creation of utility policy - place of PR in the company; establishment of QA system - description of PR activities, goals, interlinks etc.; annual planning process including activities, finance, education (training). Lessons learned are: the NPP managers were not prepared; the public was not (and still is not) prepared to obtain specific information; education is crucial in opinion winning; simple overtake of methods from others is not always applicable; strategy and feedback are necessary. Special case was the early closure Bohunice V1 NPP

  3. Comparison between TRMM PR and

    Indian Academy of Sciences (India)

    A comparison between TRMM PR rainfall estimates and rain gauge data from ANEEL and com- bined gauge/satellite ..... correctly the of the south Atlantic convergence ..... vapor, snow cover, and sea ice derived from SSM/I mea- surements ...

  4. Credibility Discourse of PR Agencies

    DEFF Research Database (Denmark)

    Isaksson, Maria; Jørgensen, Poul Erik Flyvholm

    2008-01-01

    to giving assurance of their expertise, trustworthiness and empathy, thus confirming our overall expectation that corporate credibility discourse is relatively uniform from a European perspective. However, contrary to our assumptions, the results of our study show that PR credibility discourse demonstrates...

  5. Profesi PR Identik dengan Perempuan ?

    Directory of Open Access Journals (Sweden)

    Neni Yulianita

    2004-09-01

    Full Text Available Profesi Public Relations (PR atau di Indonesia lebih dikenal dengan Humas, seringkali diidentikkan dengan profesi yang pantas dijabat oleh kaum perempuan. Adanya sebagian kalangan masyarakat yang menjudge bahwa profesi ini lebih tepat dijabat oleh kaum perempuan, dengan alasan profesi ini menuntut keterampilan, daya tarik, dan keluwesan. Dengan adanya anggapan tersebut,  tentu saja telah memberikan implikasi pada kaum laki-laki  sehingga menimbulkan keraguan pada mereka untuk menekuni bidang kajian PR/Humas di berbagai Perguruan Tinggi yang memiliki bidang ini. Ironisnya, user masih menganggap kaum laki-lakilah yang lebih tepat menjabat profesi PR, dengan anggapan antara lain bahwa laki-laki lebih energik, aktif, rasional, agresif, memiliki stamina atau fisik yang lebih kuat, dan memiliki kemampuan dalam penguasaan hardware atau teknologi komunikasi mutakhir yang lebih baik dibanding wanita yang dianggap lebih emosional, pasif, dan submisif. Anggapan ini tentu saja sangat merugikan perempuan,  walaupun hasil penelitian Robins dinyatakan bahwa,  “Tidak ada beda  laki-laki dan perempuan yang konsisten dalam kemampuan memecahkan masalah, keterampilan analitis, dorongan kompetitif, motivasi, sosiobilitas, atau kemampuan belajar”.  Untuk itu, dalam tulisan ini, penulis menyajikan jawaban apakah benar Profesi PR lebih tepat dijabat oleh Perempuan?

  6. ESO PR Highlights in 2000

    Science.gov (United States)

    2001-01-01

    At the beginning of the new millennium, ESO and its staff are facing the future with confidence. The four 8.2-m Unit Telescopes of the Very Large Telescope (VLT) are in great shape and the VLT Interferometer (VLTI) will soon have "first fringes". The intercontinental ALMA project is progressing well and concepts for extremely large optical/infrared telescopes are being studied. They can also look back at a fruitful and rewarding past year. Perhaps the most important, single development has been the rapid transition of the Very Large Telescope (VLT). From being a "high-tech project under construction" it has now become a highly proficient, world-class astronomical observatory. This trend is clearly reflected in ESO's Press Releases , as more and more front-line scientific results emerge from rich data obtained at this very efficient facility. There were also exciting news from several of the instruments at La Silla. At the same time, the ESO community may soon grow, as steps towards membership are being taken by various European countries. Throughout 2000, a total of 54 PR communications were made, with a large number of Press Photos and Video Clips, cf. the 2000 PR Index. Some of the ESO PR highlights may be accessed directly via the clickable image on the present page. ESO PR Photo 01/01 is also available in a larger (non-clickable) version [ JPEG: 566 x 566 pix - 112k]. It may be reproduced, if credit is given to the European Southern Observatory.

  7. The first quinary rare earth thiophosphates. Cs{sub 5}Ln{sub 3}X{sub 3}(P{sub 2}S{sub 6}){sub 2}(PS{sub 4}) (Ln = La, Ce, X = Br, Cl) and the quasi-quaternary Cs{sub 10}Y{sub 4}Cl{sub 10}(P{sub 2}S{sub 6}){sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Schoop, Leslie Mareike; Eger, Roland; Nuss, Juergen; Pielnhofer, Florian [Max Planck Institute for Solid State Research, Stuttgart (Germany); Lotsch, Bettina Valeska [Max Planck Institute for Solid State Research, Stuttgart (Germany); Nanosystems Initiative Munich (NIM) and Center for Nanoscience, Muenchen (Germany)

    2017-12-13

    We report the first examples of quinary rare earth thiophosphates with a fully ordered cation and anion distribution, Cs{sub 5}Ln{sub 3}X{sub 3}(P{sub 2}S{sub 6}){sub 2}(PS{sub 4}), (Ln = La, Ce and X = Br, Cl) as well as the quasi-quaternary Cs{sub 10}Y{sub 4}Cl{sub 10}(P{sub 2}S{sub 6}){sub 3}. These four new compounds crystallize in three different, unknown structure types. The yellowish, transparent, brittle Cs{sub 5}Ce{sub 3}Br{sub 3}(P{sub 2}S{sub 6}){sub 2}(PS{sub 4}) crystallizes in the orthorhombic space group Pnma (no. 62) with a = 13.276(3), b = 14.891(3), c = 19.593(4) Aa, and V = 3873(1) Aa{sup 3} in a novel structure type. Colorless crystals of Cs{sub 5}La{sub 3}Br{sub 3}(P{sub 2}S{sub 6}){sub 2}(PS{sub 4}) and Cs{sub 5}La{sub 3}Cl{sub 3}(P{sub 2}S{sub 6}){sub 2}(PS{sub 4}) are isotypic and were obtained in the monoclinic space group P2{sub 1}/m (no. 11) with a = 9.715(2), b = 14.310(3), c = 13.685(3) Aa, β = 100.16(3) and V = 1873(1) Aa{sup 3} and a = 9.513(2), b = 14.182(3), c = 13.699(3) Aa, β = 99.39(3) and V = 1823(1) Aa{sup 3}, respectively. Both structures contain isolated hexathiohypodiphosphate(IV) [P{sub 2}S{sub 6}]{sup 4-} and thiophosphate [PS{sub 4}]{sup 3-} units that are arranged alternately in layers. Cs{sub 10}Y{sub 4}Cl{sub 10}(P{sub 2}S{sub 6}){sub 3} crystallizes in colorless transparent platelets in the orthorhombic space group Pnnm (no. 58) with a = 13.153(3), b = 28.964(6), c = 7.780(2) Aa, and V = 2964(1) Aa{sup 3}. The structure is composed of isolated [P{sub 4/2}S{sub 6}]{sup 4-} octahedra containing four half occupied P positions surrounded octahedrally by sulfur. We show with Raman scattering that this disordered thiophosphate anion shows a Raman spectrum that is distinct from spectra published for other literature-known thiophosphate anions. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  8. Pathogenesis of PR3-ANCA associated vasculitis

    NARCIS (Netherlands)

    Kallenberg, C. G. M.

    2008-01-01

    Wegener's Granulomatosis (WG) is closely associated with antineutrophil cytoplasmic autoantibodies (ANCA), particularly those directed to proteinase 3 (PR3). ANCA directed to myeloperoxidase (MPO) are associated with microscopic polyangiitis (MPA) and the Churg Strauss syndrome. PR3-ANCA associated

  9. Cancer de la próstata

    OpenAIRE

    Mendoza, Lupi Alejandro; Fundación Valle de Lili; Gutierrez, María Carolina; López Cardona, Arturo

    1997-01-01

    ¿Qué es la próstata?/¿Qué es la hiperplasia benigna de próstata?/El cáncer de próstata/¿Se hereda el cáncer de próstata?/¿Cómo se presenta y hacia donde se disemina el cáncer de próstata?/¿Cómo de descubre el cáncer de próstata?/¿Qué estudia la ultrasonografía transrectal o ecografía a través de recto?/¿Cómo se analizan los niveles de PSA?/¿Cómo se clasifica el cáncer de próstata?¿Cómo se determina la terapia más adecuada para un cáncer de próstata?/¿Cuáles son las opciones de tratamiento par...

  10. Competency profile of PR professional in sport

    OpenAIRE

    Gazdíková, Lenka

    2013-01-01

    Title: Competency profile of PR professional in sport Objective: The objective is to identify competencies required to a position of PR professional in sport. The aim of a survey is to verify the level of competencies which follows compiling competency profile and comparison with existing profile of PR specialist. Methods: The objective is achieved using survey, interview and analysis of competency models database. Results: The result of this paper is competency profile of PR professional in ...

  11. Bruken av nasjonale prøver

    DEFF Research Database (Denmark)

    Skov, Poul

    2010-01-01

    Artiklen beskriver resultater fra en omfattende evaluering af brugen af de nationale prøver i norsk grundskole. De nationale prøver er blevet modtaget positivt af mange kommuner og skoleledere og i mindre grad af lærerne. Resultaterne viser også, at prøverne er styrende for undervisningen, at bru...

  12. Aliphatic amine oxides as ligands

    International Nuclear Information System (INIS)

    Garla, L.C.; Betarello, V.H.; Chiericato Junior, G.; De Giovani, W.F.

    1984-01-01

    The reaction between some hydrated lanthanide perchlorates with trimethylamine oxide (TMAO) was studied. Compounds of general formula Ln(Cl 4 ) 3 : . 5,5 TMAO (Ln = La, Pr, Er and Y) were isolated. (Author) [pt

  13. 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

  14. Photoemission of heavy fermion superconductor PrOs4Sb12 and other Pr compounds

    International Nuclear Information System (INIS)

    Imada, S.; Yamasaki, A.; Sekiyama, A.; Settai, R.; Onuki, Y.; Suga, S.; Sugawara, H.; Sato, H.; Ochiai, A.

    2004-01-01

    Full text: Strongly correlated electronic states due to Pr 4f electrons found in several Pr compounds have recently been attracting much attention. The Pr 4f electrons are much more localized than in Ce due to the lanthanoid contraction. Therefore, the number of the Pr systems that show strong electron correlation is much smaller than Ce systems. We will present a comparative study of Pr 4f electronic states in such systems as the heavy fermion superconductor PrOs 4 Sb 12 , the Kondo system PrSn 3 and the localized 4f systems Pr 4 X 3 (X = Sb and Bi). The Pr 4f electronic state was probed by means of the Pr 3d → 4f resonant photoemission (RPES). Because the kinetic energy (E K ) of the photoelectrons is as high as ∼ 900 eV, this method is much more bulk sensitive than the 4d → 4f RPES with E K ∼ 100 eV. The energy resolution could be set to about 100 meV by utilizing the soft X-rays from BL25SU in SPring-8 and the SCIENTA SES-200 analyzer. The Pr 4f excitation spectrum of PrSn 3 was found to show a very strong intensity at the Fermi level (E F ). This can be interpreted as the Kondo resonance which has been observed in the Kondo Ce and Yb compounds. In the Pr 4f spectrum of the heavy fermion superconductor PrOs 4 Sb 12 , the intensity at E F was smaller than in PrSn 3 . This clearly shows that the Kondo temperature (T K ) is much lower in PrOs 4 Sb 12 than in PrSn 3 . We have further found a strong excitation energy dependence in the RPES line shape. In the case of Pr 4 X 3 (X = Sb and Bi), the intensity at E B was much smaller than PrSn 3 and PrOs 4 Sb 12 , which is consistent with the localized character of Pr 4f electrons in Pr 4 X 3 . The Pr 4f spectra of these localized systems are qualitatively well reproduced by a cluster model calculation that takes into account the hybridization between the Pr 4f orbital and the conduction and valence bands made up by the X p and Pr 5d states

  15. Identification and expression analysis of a pathogenresponsive PR ...

    African Journals Online (AJOL)

    related (PR) proteins. PR-1 genes represent the first identified PR gene family. Most members of PR-1 gene family are not inducible by pathogen attacks. In this study, we identified a pathogen-responsive PR-1 gene designated as VqPR-1 ...

  16. Quelle préposition ?

    CERN Document Server

    Grevisse, Maurice

    1996-01-01

    Pour bien parler ou bien écrire, il faut avant tout posséder un bon vocabulaire, puis savoir bien remuer les mots, leur faire exprimer quelque chose et agencer adroitement les propositions. Il faut aussi - et cela n'est pas négligeable - amener congrûment les divers compléments des noms, des adjectifs ou des verbes ; quand ces compléments sont de construction indirecte, c'est-à-dire quand ils doivent être introduits par une préposition, on hésite parfois sur la bonne manière de les accrocher. Ne pas négliger le bon choix! Cela ne crée pas le style, sans doute, mais peut, pour une part, témoigner de sa bonne qualité.

  17. Parimad suhtekorraldusteod konkursil Baltic PR Awards

    Index Scriptorium Estoniae

    2012-01-01

    Balti riikide suhtekorraldusliidud koostöös Rahvusvahelise Avalike Suhete Assotsiatsiooniga (IPRA) korraldavad 2001. aastast iga aasta kommunikatsioonijuhtimisalast auhinnakonkurssi Baltic PR Awards

  18. 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

  19. PrP Conformational Transitions Alter Species Preference of a PrP-specific antibody

    NARCIS (Netherlands)

    Zou, W.Q.; Langeveld, J.P.M.; Xiao, X.; Chen, S.; McGeer, P.L.; Yuan, J.; Payne, M.C.; Kang, H.E.; McGeehan, J.M.; Sy, M.S.; Greenspan, N.S.; Kaplan, D.; Wang, G.X.; Parchi, P.; Hoover, E.A.; Kneale, G.; Telling, G.; Surewicz, W.; Kong, Q.; Guo, J.

    2010-01-01

    The epitope of the 3F4 antibody most commonly used in human prion disease diagnosis is believed to consist of residues Met-Lys-His-Met (MKHM) corresponding to human PrP-(109–112). This assumption is based mainly on the observation that 3F4 reacts with human and hamster PrP but not with PrP from

  20. Suured prügifirmad valmistuvad prügipuuduseks / Mirko Ojakivi

    Index Scriptorium Estoniae

    Ojakivi, Mirko

    2010-01-01

    Ragn-Sells ja Adelan Prügiveod soovivad luba jäätmete pikaajaliseks vaheladestamiseks Tallinna piiril. Ragn-Sells saaks jäätmekütusetehase planeerimise ja ehitamise ajal endale koguda ligi 35 000 t segaolmejäätmeid aastas, Adelan Prügiveod sooviks ladestada ligi 50 000 t prügi aastas

  1. PrEP (Pre-Exposure Prophylaxis) 101

    Science.gov (United States)

    ... than 70%. Your risk of getting HIV from sex can be even lower if you combine PrEP with condoms and other prevention methods. Download PrEP 101 Consumer Info Sheet Vital Signs Fact Sheet on Daily Pill Can Prevent HIV (PrEP) Expand All Collapse All Video Introductions to PrEP What is PrEP? A Brief ...

  2. 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.

  3. 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

  4. 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

  5. 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

  6. Coordination polyhedra LnFn (Ln=La-Lu) in crystal structure

    International Nuclear Information System (INIS)

    Vologzhanina, A.V.; Pushkin, D.V.; Serezhkin, V.N.

    2006-01-01

    Peculiarities of stereochemistry of lanthanides (Ln) surrounded by fluorine atoms were studied by means of the Voronoi-Dirichlet polyhedra (PVD) and method of crossing spheres, 118 compounds are presented in the structure. It has been found that coordination numbers (CN) of Ln atoms change from 6 to 12, nine types of LnF n coordination polyhedra are formed in the process, Ln-F bond lengths have changes by 0.2-0.7 A in accordance to CN. It is found that in spite of significant variation of bond lengths volume of PVD Ln atoms is determined by their nature and oxidation state. It has been found that the change in radii of spherical domains, which volume is equal to the volume of PVD Ln atoms, is accompanied by tetrad-effect [ru

  7. Crystallization and structural approaches of rare earths aluminosilicate glasses (Ln = La, Y, Sc)

    International Nuclear Information System (INIS)

    Sadiki, N.; Coutures, J.P.; Hennet, L.; Florian, P.; Vaills, Y.; Massiot, D.

    2010-01-01

    The crystallization behaviour of aluminosilicate glasses of lanthanum, yttrium and scandium has been studied by DTA, XRD, SEM-EDX and EPMA analysis. Young modulus E and hardness H have been measured by using nano-indentation and elastic modulus C 11 and C 44 by Brillouin scattering. The Young modulus measured by nano-indentation agree to those determined by Brillouin scattering and those calculated using Makishima-Mackenzie and Rocherulle model's. The results of DTA analysis indicate that (a) the glass transition temperatures T g are higher for yttrium and scandium containing glasses than their lanthanum counterparts, the melting observed in the yttrium glasses and recently in the scandium glasses correspond to the ternary eutectic Ln 2 O 3 -Al 2 O 3 -SiO 2 (Ln = Y, Sc) (b) the thermal stability is strongly related to the ionic radii of the rare earth. The last results obtained on scandium containing glasses confirm this hypothesis. The XRD results show that the nature of the observed crystallized phases is consistent with the phase diagrams. We also have investigated by NMR-MAS of 27 Al (high field- 17.6 T) these glasses. The results indicate that Al(V) species are correlated to the ionic radii of the rare earth. X-rays and neutron scattering experiments have been respectively performed on the high energy diffraction beam lines ID11 and ID15 at ESRF. The interatomic distances and first-shell coordination numbers were determined. The results are consistent with those performed by NMR-MAS. (authors)

  8. Thermoelectric power of PrMg3

    Science.gov (United States)

    Isikawa, Yosikazu; Somiya, Kazuya; Koyanagi, Huruto; Mizushima, Toshio; Kuwai, Tomohiko; Tayama, Takashi

    2010-01-01

    PrMg3 is supposed to be one of the strongly correlated electron systems originated from the hybridization between the Pr 4f and conduction electrons, because the gigantic electronic specific heat coefficient C/T was observed at low temperatures. However, a typical behaviour of - ln T dependence was not observed in the temperature dependence of the electrical resistivity. The thermoelectric power S is a powerful tool to investigate the density of states at the Fermi energy. We measured carefully the thermoelectric power of PrMg3 in the temperature range between 2 and 300 K. S is extremely small, ranged within ±1 μV/K over the whole temperature. The value of S/T at low temperature limit was also significantly smaller than expected from the specific heat results. We therefore conclude that the density of state at the Fermi level is not enhanced in PrMg3.

  9. Thermoelectric power of PrMg3

    International Nuclear Information System (INIS)

    Isikawa, Yosikazu; Somiya, Kazuya; Koyanagi, Huruto; Mizushima, Toshio; Kuwai, Tomohiko; Tayama, Takashi

    2010-01-01

    PrMg 3 is supposed to be one of the strongly correlated electron systems originated from the hybridization between the Pr 4f and conduction electrons, because the gigantic electronic specific heat coefficient C/T was observed at low temperatures. However, a typical behaviour of - ln T dependence was not observed in the temperature dependence of the electrical resistivity. The thermoelectric power S is a powerful tool to investigate the density of states at the Fermi energy. We measured carefully the thermoelectric power of PrMg 3 in the temperature range between 2 and 300 K. S is extremely small, ranged within ±1 μV/K over the whole temperature. The value of S/T at low temperature limit was also significantly smaller than expected from the specific heat results. We therefore conclude that the density of state at the Fermi level is not enhanced in PrMg 3 .

  10. Crystal Field Levels of Pr3+ in PrFeO3 and PrGaO3 Determined by Inelastic Neutron Scattering

    DEFF Research Database (Denmark)

    Feldmann, K.; Henning, K.; Kaun, L.

    1975-01-01

    The crystal field splitting of the 3H4 ground state of the Pr ion in PrFeO3 and PrGaO3 has been investigated by inelastic scattering of thermal neutrons. At several temperatures the transitions have been measured by TAS and TOF methods for polycrystalline PrFeO3 and by the TOF method...... for polycrystalline PrGaO3. Energy level schemes which are different for these materials are given....

  11. 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.)

  12. On the subgroups of PR groups

    International Nuclear Information System (INIS)

    Lebedenko, V.M.

    1979-01-01

    The subgroups of PR-groups are being studied, i.e., the subgroups of connected and simply connected nonabelian Lie groups, their Lie algebras being defined by the commuting relations of the type [Hsub(i), Hsub(j)] = rsub(ij)Hsub(i) (i 1 of PR-group G there exists such complementary subgroup G 2 and that group G is expanded in semidirect product G = G 1 xG 2 [ru

  13. Revisiting progesterone receptor (PR) actions in breast cancer: Insights into PR repressive functions.

    Science.gov (United States)

    Proietti, Cecilia J; Cenciarini, Mauro E; Elizalde, Patricia V

    2018-05-01

    Progesterone receptor (PR) is a master regulator in female reproductive tissues that controls developmental processes and proliferation and differentiation during the reproductive cycle and pregnancy. PR also plays a role in progression of endocrine-dependent breast cancer. As a member of the nuclear receptor family of ligand-dependent transcription factors, the main action of PR is to regulate networks of target gene expression in response to binding its cognate steroid hormone, progesterone. Liganded-PR transcriptional activation has been thoroughly studied and associated mechanisms have been described while progesterone-mediated repression has remained less explored. The present work summarizes recent advances in the understanding of how PR-mediated repression is accomplished in breast cancer cells and highlights the significance of fully understanding the determinants of context-dependent PR action. Copyright © 2018 Elsevier Inc. All rights reserved.

  14. 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.

  15. E-PR technologies in political party activities

    OpenAIRE

    Tereshchuk Vitaliy Ivanovych

    2016-01-01

    The article discusses the role of the Internet as an important communicative tool in the field of political PR. The article reviews the characteristics of PR-activities on the Internet and the features of e-PR in the political sphere. Particular attention is paid to the system of political party’s e-PR tools.

  16. PrP N-terminal domain triggers PrPSc-like aggregation of Dpl

    International Nuclear Information System (INIS)

    Erlich, Paul; Cesbron, Jean-Yves; Lemaire-Vieille, Catherine; Curt, Aurelie; Andrieu, Jean-Pierre; Schoehn, Guy; Jamin, Marc; Gagnon, Jean

    2008-01-01

    Transmissible spongiform encephalopathies are fatal neurodegenerative disorders thought to be transmitted by self-perpetuating conformational conversion of a neuronal membrane glycoprotein (PrP C , for 'cellular prion protein') into an abnormal state (PrP Sc , for 'scrapie prion protein'). Doppel (Dpl) is a protein that shares significant biochemical and structural homology with PrP C . In contrast to its homologue PrP C , Dpl is unable to participate in prion disease progression or to achieve an abnormal PrP Sc -like state. We have constructed a chimeric mouse protein, composed of the N-terminal domain of PrP C (residues 23-125) and the C-terminal part of Dpl (residues 58-157). This chimeric protein displays PrP-like biochemical and structural features; when incubated in presence of NaCl, the α-helical monomer forms soluble β-sheet-rich oligomers which acquire partial resistance to pepsin proteolysis in vitro, as do PrP oligomers. Moreover, the presence of aggregates akin to protofibrils is observed in soluble oligomeric species by electron microscopy

  17. 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…

  18. La préservation, atout essentiel pour contrer la précarité des ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    La préservation, atout essentiel pour contrer la précarité des moyens de subsistance en ... Union mondiale pour la conservation de la nature et des ressources ... la recherche menée dans les domaines des sciences sociales, des sciences ...

  19. Pr-magnetism in the quasi-skutterudite compound PrFe2Al8.

    Science.gov (United States)

    Nair, Harikrishnan S; Ogunbunmi, Michael O; Kumar, C M N; Adroja, D T; Manuel, P; Fortes, D; Taylor, J; Strydom, A M

    2017-08-31

    The intermetallic compound PrFe 2 Al 8 that possesses a three-dimensional network structure of Al polyhedra centered at the transition metal element Fe and the rare earth Pr is investigated through neutron powder diffraction and inelastic neutron scattering in order to elucidate the magnetic ground state of Pr and Fe and the crystal field effects of Pr. Our neutron diffraction study confirms long-range magnetic order of Pr below [Formula: see text] K in this compound. Subsequent magnetic structure estimation reveals a magnetic propagation vector [Formula: see text] with a magnetic moment value of [Formula: see text]/Pr along the orthorhombic c-axis and evidence the lack of ordering in the Fe sublattice. The inelastic neutron scattering study reveals one crystalline electric field excitation near 19 meV at 5 K in PrFe 2 Al 8 . The energy-integrated intensity of the 19 meV excitation as a function of [Formula: see text] follows the square of the magnetic form factor of [Formula: see text] thereby confirming that the inelastic excitation belongs to the Pr sublattice. The second sum rule applied to the dynamic structure factor indicates only 1.6(2) [Formula: see text] evolving at the 19 meV peak compared to the 3.58 [Formula: see text] for free [Formula: see text], indicating that the crystal field ground state is magnetic and the missing moment is associated with the resolution limited quasi-elastic line. The magnetic order occurring in Pr in PrFe 2 Al 8 is counter-intuitive to the symmetry-allowed crystal field level scheme, hence, is suggestive of exchange-mediated mechanisms of ordering stemming from the magnetic ground state of the crystal field levels.

  20. 75 FR 44847 - Proposed Collection; Comment Request for Forms 943, 943-PR, 943-A, and 943A-PR

    Science.gov (United States)

    2010-07-29

    ... 943, 943-PR, 943- A, and 943A-PR AGENCY: Internal Revenue Service (IRS), Treasury. ACTION: Notice and... comments concerning Forms 943, Employer's Annual Tax Return for Agricultural Employees, 943-PR, Planilla..., Agricultural Employer's Record of Federal Tax Liability, and 943A-PR, Registro De La Obligacion Contributiva...

  1. 78 FR 47051 - Proposed Collection; Comment Request for Forms 943, 943-PR, 943-A, and 943A-PR

    Science.gov (United States)

    2013-08-02

    ... 943, 943-PR, 943- A, and 943A-PR AGENCY: Internal Revenue Service (IRS), Treasury. ACTION: Notice and..., 943-PR, Planilla Para La Declarcion Anual De La Contribucion Federal Del Patrono De Empleados Agricolas, 943-A, Agricultural Employer's Record of Federal Tax Liability, and 943A-PR, Registro De La...

  2. 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

  3. Optimization of Pr3+:ZBLAN fiber amplifiers

    DEFF Research Database (Denmark)

    Pedersen, B.; Miniscalco, J. W.; Quimby, R. S.

    1992-01-01

    Experimental parameters have been measured and used in a quantitative model of Pr3+-doped fluorozirconate fiber amplifiers. The optimum cutoff wavelength was determined to be 800 nm and the gain for 400 mW of pump was found to increase from 12 to 34 dB if the NA was increased from 0.15 to 0...

  4. Prøvetagning af grundvand

    DEFF Research Database (Denmark)

    Sørensen, Inga

    Bogen fokuserer på prøveatgning af grundvand og drikkevand til forskellige formål såsom undersøgelse af forurenede grunde, grundvandsmonitering samt produktion af drikkevand. Da grundvand i sagens natur findes under jordoverfladen, beskriver bogen også væsentlige forhold om hydrogeologi og...

  5. Mechanistic prospective for human PrPC conversion to PrPSc: Molecular dynamic insights

    OpenAIRE

    Nooshin Azari; Mohammad Reza Dayer; Nematollah Razmi; Mohammad Saaid Dayer

    2013-01-01

    PrPC conversion to PrPSc isoform is the main known cause for prion diseases including Crutzfeldt-Jakob, Gerstmann-Sträussler-Sheinker syndrome and fatal familial insomnia in human. The precise mechanism underling this conversion is yet to be well understood. In the present work, using the coordinate file of PrPC (available on the Protein Data Bank) as a starting structure, separate molecular dynamic simulations were carried out at neutral and acidic pH in an explicit water box at 37°C and 1 ...

  6. Interaction between Shadoo and PrP Affects the PrP-Folding Pathway.

    Science.gov (United States)

    Ciric, Danica; Richard, Charles-Adrien; Moudjou, Mohammed; Chapuis, Jérôme; Sibille, Pierre; Daude, Nathalie; Westaway, David; Adrover, Miguel; Béringue, Vincent; Martin, Davy; Rezaei, Human

    2015-06-01

    Prion diseases are characterized by conformational changes of a cellular prion protein (PrP(C)) into a β-sheet-enriched and aggregated conformer (PrP(Sc)). Shadoo (Sho), a member of the prion protein family, is expressed in the central nervous system (CNS) and is highly conserved among vertebrates. On the basis of histoanatomical colocalization and sequence similarities, it is suspected that Sho and PrP may be functionally related. The downregulation of Sho expression during prion pathology and the direct interaction between Sho and PrP, as revealed by two-hybrid analysis, suggest a relationship between Sho and prion replication. Using biochemical and biophysical approaches, we demonstrate that Sho forms a 1:1 complex with full-length PrP with a dissociation constant in the micromolar range, and this interaction consequently modifies the PrP-folding pathway. Using a truncated PrP that mimics the C-terminal C1 fragment, an allosteric binding behavior with a Hill number of 4 was observed, suggesting that at least a tetramerization state occurs. A cell-based prion titration assay performed with different concentrations of Sho revealed an increase in the PrP(Sc) conversion rate in the presence of Sho. Collectively, our observations suggest that Sho can affect the prion replication process by (i) acting as a holdase and (ii) interfering with the dominant-negative inhibitor effect of the C1 fragment. Since the inception of the prion theory, the search for a cofactor involved in the conversion process has been an active field of research. Although the PrP interactome presents a broad landscape, candidates corresponding to specific criteria for cofactors are currently missing. Here, we describe for the first time that Sho can affect PrP structural dynamics and therefore increase the prion conversion rate. A biochemical characterization of Sho-PrP indicates that Sho acts as an ATP-independent holdase. Copyright © 2015, American Society for Microbiology. All Rights

  7. Progesterone receptors (PR) mediate STAT actions: PR and prolactin receptor signaling crosstalk in breast cancer models.

    Science.gov (United States)

    Leehy, Katherine A; Truong, Thu H; Mauro, Laura J; Lange, Carol A

    2018-02-01

    Estrogen is the major mitogenic stimulus of mammary gland development during puberty wherein ER signaling acts to induce abundant PR expression. PR signaling, in contrast, is the primary driver of mammary epithelial cell proliferation in adulthood. The high circulating levels of progesterone during pregnancy signal through PR, inducing expression of the prolactin receptor (PRLR). Cooperation between PR and prolactin (PRL) signaling, via regulation of downstream components in the PRL signaling pathway including JAKs and STATs, facilitates the alveolar morphogenesis observed during pregnancy. Indeed, these pathways are fully integrated via activation of shared signaling pathways (i.e. JAKs, MAPKs) as well as by the convergence of PRs and STATs at target genes relevant to both mammary gland biology and breast cancer progression (i.e. proliferation, stem cell outgrowth, tissue cell type heterogeneity). Thus, rather than a single mediator such as ER, transcription factor cascades (ER>PR>STATs) are responsible for rapid proliferative and developmental programming in the normal mammary gland. It is not surprising that these same mediators typify uncontrolled proliferation in a majority of breast cancers, where ER and PR are most often co-expressed and may cooperate to drive malignant tumor progression. This review will primarily focus on the integration of PR and PRL signaling in breast cancer models and the importance of this cross-talk in cancer progression in the context of mammographic density. Components of these PR/PRL signaling pathways could offer alternative drug targets and logical complements to anti-ER or anti-estrogen-based endocrine therapies. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Prévalence, facteurs associés et prédisposant au syndrome ...

    African Journals Online (AJOL)

    Introduction: Le syndrome métabolique est associé aux maladies cardiovasculaires. L'infection au VIH est devenue aujourd'hui une maladie chronique. L'objectif de cette étude est de déterminer la prévalence, les facteurs associés et prédisposant au syndrome métabolique chez les patients infectés par le VIH sous ...

  9. Der Effekt von Akupunktur in der Prävention von Prüfungsangst

    OpenAIRE

    Krüger, Peter

    2017-01-01

    Prüfungsangst ist ein weit verbreitetes gesellschaftliches Phänomen, das bisher in nur wenigen wissenschaftlichen Ansätzen untersucht wurde. Die Zahl der Studenten, die Gehirn - Doping zur Leistungssteigerung und zur Minimierung von Prüfungsangst nutzen, steigt stetig an. In bisherigen Studien wurde Akupunktur an Herz 7 als vielversprechende Behandlungsalternative dargestellt. Basierend auf diesen Ergebnissen, wurde in dieser Arbeit untersucht, ob eine Einzelpunktakupunktur an Herz 7 die ...

  10. 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.)

  11. Piperazine derivatives inhibit PrP/PrP(res) propagation in vitro and in vivo.

    Science.gov (United States)

    Leidel, Fabienne; Eiden, Martin; Geissen, Markus; Hirschberger, Thomas; Tavan, Paul; Giese, Armin; Kretzschmar, Hans A; Schätzl, Hermann; Groschup, Martin H

    2014-02-28

    Prion diseases are fatal neurodegenerative disorders, which are not curable and no effective treatment exists so far. The major neuropathological change in diseased brains is the conversion of the normal cellular form of the prion protein PrPc(C) into a disease-associated isoform PrP(Sc). PrP(Sc) accumulates into multimeres and fibrillar aggregates, which leads to the formation of amyloid plaques. Increasing evidence indicates a fundamental role of PrP(Sc) species and its aggregation in the pathogenesis of prion diseases, which initiates the pathological cascade and leads to neurodegeneration accompanied by spongiform changes. In search of compounds that have the potential to interfere with PrP(Sc) formation and propagation, we used a cell based assay for the screening of potential aggregation inhibitors. The assay deals with a permanently prion infected cell line that was adapted for a high-throughput screening of a compound library composed of 10,000 compounds (DIVERset 2, ChemBridge). We could detect six different classes of highly potent inhibitors of PrP(Sc) propagation in vitro and identified piperazine derivatives as a new inhibitory lead structure, which increased incubation time of scrapie infected mice. Copyright © 2014 Elsevier Inc. All rights reserved.

  12. Prion protein (PrP) gene-knockout cell lines: insight into functions of the PrP

    OpenAIRE

    Sakudo, Akikazu; Onodera, Takashi

    2015-01-01

    Elucidation of prion protein (PrP) functions is crucial to fully understand prion diseases. A major approach to studying PrP functions is the use of PrP gene-knockout (Prnp ?/?) mice. So far, six types of Prnp ?/? mice have been generated, demonstrating the promiscuous functions of PrP. Recently, other PrP family members, such as Doppel and Shadoo, have been found. However, information obtained from comparative studies of structural and functional analyses of these PrP family proteins do not ...

  13. Microstructure and martensitic transformation of Ni-Ti-Pr alloys

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Chunwang [Inner Mongolia University of Technology, College of Science, Hohhot (China); Shanghai Maritime University, College of Arts and Sciences, Shanghai (China); Zhao, Shilei; Jin, Yongjun; Hou, Qingyu [Inner Mongolia University of Technology, College of Science, Hohhot (China); Guo, Shaoqiang [Beihang University, Key Laboratory of Micro-nano Measurement, Manipulation and Physics (Ministry of Education), Department of Physics, Beijing (China)

    2017-09-15

    The effect of Pr addition on the microstructure and martensitic transformation behavior of Ni{sub 50}Ti{sub 50-x}Pr{sub x} (x = 0, 0.1, 0.3, 0.5, 0.7, 0.9) alloys were investigated experimentally. Results show that the microstructures of Ni-Ti-Pr alloys consist of the NiTi matrix and the NiPr precipitate with the Ti solute. The martensitic transformation start temperature decreases gradually with the increase in Pr fraction. The stress around NiPr precipitates is responsible for the decrease in martensitic transformation temperature with the increase in Pr fraction in Ni-Ti-Pr alloys. (orig.)

  14. 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

  15. Præverbalitet i Musikterapi

    Directory of Open Access Journals (Sweden)

    Niels Hannibal

    2003-03-01

    Full Text Available Denne artikel er en oversættelse af mit foredrag på verdenskongressen i musikterapi i Oxford 2002. Den er baseret på min ph.d. afhandling »Præverbal Overføring i Musikterapi«, der blev forsvaret juni 2001. Formålet med artiklen er at validere min forskning om præverbal overføring i musikterapi i den musikalske interaktion gennem formidling af den pragmatiske anvendelse. I artiklen argumenterer jeg for anvendelse af Sterns psykologiske udviklingsteori og Sotolorow & Atwoodes teori om psykoterapi som fortolkningskontekst for musikalsk interaktion, når fokus er interaktion, relation og overføring. Det illustreres gennem en case analyse hvorledes begreberne kan anvendes på kliniske data. Det konkluderes at psykologisk teori og tænkning er nødvendig for at kunne forstå og beskrive musikalsk interaktion i et psykologisk perspektiv.

  16. Favoriser la prévention

    International Development Research Centre (IDRC) Digital Library (Canada)

    Les limites de ces axes d'in- tervention ... Le principal intérêt d'une stratégie nationale de prévention réside .... ricain pour le Développement Intégré (RADI,) le Comité de. Lutte contre ... logistiques et humains suffisants pour prendre en charge les cas. ... niveaux, participent à une dispersion des initiatives, des stratégies et ...

  17. Insight into Eu redox and Pr

    NARCIS (Netherlands)

    Zhou, Rongfu; Lin, Litian; Liu, Chunmeng; Dorenbos, P.; Tao, Ye; Huang, Yan; Liang, Hongbin

    2018-01-01

    A series of Ln-doped KSrPO4 (Ln = Ce3+, Eu3+, Eu2+, Pr3+) phosphors are prepared through a high-temperature solid-state method. The KSrPO4 compound is confirmed to possess a β-K2SO4 structure with the Pnma

  18. Advancing tendencies? PR leadership, general leadership, and leadership pedagogy

    OpenAIRE

    McKie, D; Willis, P

    2014-01-01

    What are the best ways to advance PR leadership? In exploring answers, we consider the last two decades of PR literature and identify two main tendencies. We link those two with general leadership literature and practices, as well as with literature on leadership pedagogy. We conclude that, rather than recent moves to look within the field, without self-reflection, to existing PR perspectives and figures for solutions, looking outwards has greater potential to transform not only the PR leader...

  19. Genetic determinants of P wave duration and PR segment

    NARCIS (Netherlands)

    Verweij, Niek; Mateo Leach, Irene; van den Boogaard, Malou; van Veldhuisen, Dirk J.; Christoffels, Vincent M.; Hillege, Hans L.; van Gilst, Wiek H.; Barnett, Phil; de Boer, Rudolf A.; van der Harst, Pim

    2014-01-01

    The PR interval on the ECG reflects atrial depolarization and atrioventricular nodal delay which can be partially differentiated by P wave duration and PR segment, respectively. Genome-wide association studies have identified several genetic loci for PR interval, but it remains to be determined

  20. Genetic Determinants of P Wave Duration and PR Segment

    NARCIS (Netherlands)

    Verweij, Niek; Mateo Leach, Irene; van den Boogaard, Malou; van Veldhuisen, Dirk J.; Christoffels, Vincent M.; Hillege, Hans L.; van Gilst, Wiek H.; Barnett, Phil; de Boer, Rudolf A.; van der Harst, Pim

    Background-The PR interval on the ECG reflects atrial depolarization and atrioventricular nodal delay which can be partially differentiated by P wave duration and PR segment, respectively. Genome-wide association studies have identified several genetic loci for PR interval, but it remains to be

  1. On orbits and admissible subalgebras for the PR groups

    International Nuclear Information System (INIS)

    Lebedenko, V.M.

    1977-01-01

    The PR-groups (Lie groups with commutation relations of [Hsub(i),Hsub(0)] = rsub(ij)Hsub(i) (i< j)-type) are investigated within the Kirillov orbit method. Orbits for all the PR-groups are constructed in a general form. For some classes of PR-groups orbits and admissible subalgebras are obtained in an explicit form

  2. Recombinant PrPSc shares structural features with brain-derived PrPSc: Insights from limited proteolysis.

    Science.gov (United States)

    Sevillano, Alejandro M; Fernández-Borges, Natalia; Younas, Neelam; Wang, Fei; R Elezgarai, Saioa; Bravo, Susana; Vázquez-Fernández, Ester; Rosa, Isaac; Eraña, Hasier; Gil, David; Veiga, Sonia; Vidal, Enric; Erickson-Beltran, Melissa L; Guitián, Esteban; Silva, Christopher J; Nonno, Romolo; Ma, Jiyan; Castilla, Joaquín; R Requena, Jesús

    2018-01-01

    Very solid evidence suggests that the core of full length PrPSc is a 4-rung β-solenoid, and that individual PrPSc subunits stack to form amyloid fibers. We recently used limited proteolysis to map the β-strands and connecting loops that make up the PrPSc solenoid. Using high resolution SDS-PAGE followed by epitope analysis, and mass spectrometry, we identified positions ~116/118, 133-134, 141, 152-153, 162, 169 and 179 (murine numbering) as Proteinase K (PK) cleavage sites in PrPSc. Such sites likely define loops and/or borders of β-strands, helping us to predict the threading of the β-solenoid. We have now extended this approach to recombinant PrPSc (recPrPSc). The term recPrPSc refers to bona fide recombinant prions prepared by PMCA, exhibiting infectivity with attack rates of ~100%. Limited proteolysis of mouse and bank vole recPrPSc species yielded N-terminally truncated PK-resistant fragments similar to those seen in brain-derived PrPSc, albeit with varying relative yields. Along with these fragments, doubly N- and C-terminally truncated fragments, in particular ~89/97-152, were detected in some recPrPSc preparations; similar fragments are characteristic of atypical strains of brain-derived PrPSc. Our results suggest a shared architecture of recPrPSc and brain PrPSc prions. The observed differences, in particular the distinct yields of specific PK-resistant fragments, are likely due to differences in threading which result in the specific biochemical characteristics of recPrPSc. Furthermore, recombinant PrPSc offers exciting opportunities for structural studies unachievable with brain-derived PrPSc.

  3. Die prädikatsergänzung (das prädikatsattribut in der Slovenischen Syntax

    Directory of Open Access Journals (Sweden)

    Breda Pogorelec

    1972-12-01

    Full Text Available In der vorliegenden Abhandlung wird die erwähnte Problematik in der slovenischen grammatischen -Überlieferung behandelt und mit interessanten Ergebnissen vor allem der tschechischen Sprachtheorie ergänzt, es wird der Terminus Prädikatsergänzung gegenüber dem Terminus Prädikatsattribut begründet; auf dieser Grundlage werden auch die bisher behandelten Arten von Prädikatsergänzungen mit neuen ergänzt. Dabei findet wenn nur möglich das einfache Transformationsverfahren Verwendung, das die Veranschaulichung der stufenweisen Determinierung durch das Prädikatsattribut ermöglicht. Das Material entstammt vorwiegend der Sprache der Kunst, der Grund dafür ist vor allem in der Tatsache zu suchen, daß in dieser Sprache dieser Form die Rolle eines natürlichen Kondensators zufällt, weshalb sie verhältnismäßig häufig vorkommt. Die Abhandlung befaßt sich eingehender auch mit dem Problem der Wortfolge und berührt auch die graphische Darstellung der bei der Prädikatsergänzung üblichen Pausen.

  4. Bolonia y la buena práctica de las prácticas

    OpenAIRE

    García Delgado, Javier

    2016-01-01

    A propósito de la implantación del controvertido “plan Bolonia” se están difundiendo algunas ideas negativas en relación con una supuesta “mercantilización” de la universidad, algunas relacionadas con la explotación de los estudiantes a través de las prácticas en empresas, o prácticas externas, sobre las cuales se reflexiona en este artículo. ¿Qué hemos aprendido tras las ya casi tres décadas transcurridas desde la promulgación del decreto del año 81 que autorizaba este tipo de prácticas? Ese...

  5. 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.

  6. Growth and scintillation properties of Pr doped YAP with different Pr concentrations

    International Nuclear Information System (INIS)

    Yanagida, Takayuki; Kamada, Kei; Fujimoto, Yutaka; Sugiyama, Makoto; Furuya, Yuki; Yamaji, Akihiro; Yokota, Yuui; Yoshikawa, Akira

    2010-01-01

    Pr 3+ 0.2, 0.75, and 3 mol% doped YAP single crystalline scintillators were grown by using the micro-pulling down (μ-PD) method. Pr 3+ 0.05 mol% doped YAP was also prepared by using the Czochralski method. In transmittance spectra, 4f-5d absorption line appeared at 230 nm. The μ-PD grown crystals showed intense emission at 290 nm while the Czochralski grown one showed an emission peak at 245 nm in radio luminescence spectra under X-ray excitation. Among them, the Czochralski grown one exhibited the highest light yield under 137 Cs 662 keV excitation and the absolute light yield of this sample was estimated to be 20400±2000 ph/MeV. The decay time constants of these scintillators were around 10 ns due to Pr 3+ 5d-4f transition.

  7. Growth and scintillation properties of Pr doped YAP with different Pr concentrations

    Energy Technology Data Exchange (ETDEWEB)

    Yanagida, Takayuki, E-mail: t_yanagi@tagen.tohoku.ac.j [Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577 (Japan); Kamada, Kei; Fujimoto, Yutaka; Sugiyama, Makoto; Furuya, Yuki [Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577 (Japan); Yamaji, Akihiro [New Industry Creation Hatchery Center (NICHe), Tohoku University, 6-6-10 Aoba, Aramaki, Aoba-ku, Sendai 980-8579 (Japan); Yokota, Yuui [Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577 (Japan); Yoshikawa, Akira [Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577 (Japan); New Industry Creation Hatchery Center (NICHe), Tohoku University, 6-6-10 Aoba, Aramaki, Aoba-ku, Sendai 980-8579 (Japan)

    2010-11-21

    Pr{sup 3+} 0.2, 0.75, and 3 mol% doped YAP single crystalline scintillators were grown by using the micro-pulling down ({mu}-PD) method. Pr{sup 3+} 0.05 mol% doped YAP was also prepared by using the Czochralski method. In transmittance spectra, 4f-5d absorption line appeared at 230 nm. The {mu}-PD grown crystals showed intense emission at 290 nm while the Czochralski grown one showed an emission peak at 245 nm in radio luminescence spectra under X-ray excitation. Among them, the Czochralski grown one exhibited the highest light yield under {sup 137}Cs 662 keV excitation and the absolute light yield of this sample was estimated to be 20400{+-}2000 ph/MeV. The decay time constants of these scintillators were around 10 ns due to Pr{sup 3+} 5d-4f transition.

  8. PrPC from stem cells to cancer

    Directory of Open Access Journals (Sweden)

    Séverine eMartin-Lannerée

    2014-09-01

    Full Text Available The cellular prion protein PrPC was initially discovered as the normal counterpart of the pathological scrapie prion protein PrPSc, the main component of the infectious agent of Transmissible Spongiform Encephalopathies. While clues as to the physiological function of this ubiquitous protein were greatly anticipated from the development of knock-out animals, PrP-null mice turned out to be viable and to develop without major phenotypic abnormalities. Notwithstanding, the discovery that hematopoietic stem cells from PrP-null mice have impaired long-term repopulating potential has set the stage for investigating into the role of PrPC in stem cell biology. A wealth of data have now exemplified that PrPC is expressed in distinct types of stem cells and regulates their self-renewal as well as their differentiation potential. A role for PrPC in the fate restriction of embryonic stem cells has further been proposed. Paralleling these observations, an overexpression of PrPC has been documented in various types of tumours. In line with the contribution of PrPC to stemness and to the proliferation of cancer cells, PrPC was recently found to be enriched in subpopulations of tumour-initiating cells. In the present review, we summarize the current knowledge of the role played by PrPC in stem cell biology and discuss how the subversion of its function may contribute to cancer progression.

  9. Exotic behaviours in the Pr-based filled skutterudites

    International Nuclear Information System (INIS)

    Sato, H; Sugawara, H; Namiki, T; Saha, S R; Osaki, S; Matsuda, T D; Aoki, Y; Inada, Y; Shishido, H; Settai, R; Onuki, Y

    2003-01-01

    The exotic features of the Pr-based filled skutterudites are reviewed based on the electronic transport properties, specific heat and de Haas-van Alphen experiments, putting the emphasis on PrFe 4 P 12 and PrOs 4 Sb 12 . As references, the experiments on the related La- and Ce-filled skutterudites are also examined and discussed. Compared to their La reference compounds, the Fermi surface is very similar in PrOs 4 Sb 12 , suggesting the well localized character of 4f electrons, while it looks largely different in PrFe 4 P 12 . For the cyclotron effective mass, both PrFe 4 P 12 and PrOs 4 Sb 12 exhibit a strong enhancement, in reasonable agreement with the large specific heat coefficient

  10. PrP expression, PrPSc accumulation and innervation of splenic compartments in sheep experimentally infected with scrapie.

    Directory of Open Access Journals (Sweden)

    Randi Sørby

    Full Text Available BACKGROUND: In prion disease, the peripheral expression of PrP(C is necessary for the transfer of infectivity to the central nervous system. The spleen is involved in neuroinvasion and neural dissemination in prion diseases but the nature of this involvement is not known. The present study undertook the investigation of the spatial relationship between sites of PrP(Sc accumulation, localisation of nerve fibres and PrP(C expression in the tissue compartments of the spleen of scrapie-inoculated and control sheep. METHODOLOGY/PRINCIPAL FINDINGS: Laser microdissection and quantitative PCR were used to determine PrP mRNA levels and results were compared with immunohistochemical protocols to distinguish PrP(C and PrP(Sc in tissue compartments of the spleen. In sheep experimentally infected with scrapie, the major sites of accumulation of PrP(Sc in the spleen, namely the lymphoid nodules and the marginal zone, expressed low levels of PrP mRNA. Double immunohistochemical labelling for PrP(Sc and the pan-nerve fibre marker, PGP, was used to evaluate the density of innervation of splenic tissue compartments and the intimacy of association between PrP(Sc and nerves. Some nerve fibres were observed to accompany blood vessels into the PrP(Sc-laden germinal centres. However, the close association between nerves and PrP(Sc was most apparent in the marginal zone. Other sites of close association were adjacent to the wall of the central artery of PALS and the outer rim of germinal centres. CONCLUSIONS/SIGNIFICANCE: The findings suggest that the degree of PrP(Sc accumulation does not depend on the expression level of PrP(C. Though several splenic compartments may contribute to neuroinvasion, the marginal zone may play a central role in being the compartment with most apparent association between nerves and PrP(Sc.

  11. Radio- and VUV - Excited Luminescence of YAP:Ce, YAP:Pr and YAG:Pr

    Science.gov (United States)

    2001-01-01

    Pr 3+ ions.", Acta Physica Polonica A, 90 pp.407-10, 1996. 6. C. Pedrini, D. Bouttet, C. Dujardin, B. Moine, I. Dafinei, P. Lecoq, M. Koselja, K...34Spectroscopy and thermoluminescence of LuAIO 3:Ce" Acta Physica Polonica A,.90, pp.377-383, 1996 17. A.J. Wojtowicz, J. Glodo, W. Drozdowski, K.R. Przegietka...Malinowski, M.F. Joubert, B. Jacquier. "Simultaneous laser action at blue and orange wavelengths in YAG:Pr 3+ Physica Status Solidi A, 140, pp.K49-52, 1993 5

  12. Présentation des auteurs

    OpenAIRE

    2016-01-01

    Jean-Pierre Cléro, université de Haute-Normandie, Rouen Andrea Emiliani, président de l’academia Clementina de Bologna (Italie) Pascal Griener, université de Neuchâtel (Suisse) Yves Hersant, École des hautes études en sciences sociales, Paris Philippe Junod, université de Lausane (Suisse) Françoise Knopper, université de Toulouse 2-Le Mirail Centre de Recherches et d’Études germaniques (CREG) Didier Laroque, École supérieure d’architecture, Paris Val de Seine Alain Michel, de l’Institut Jacki...

  13. Thermal reorientation of hydrogenic Pr3+ centers

    International Nuclear Information System (INIS)

    Jones, G. D.

    1996-01-01

    Sets of five multi-hydrogenic centers of both CaF 2 :Pr 3+ and SrF 2 :Pr 3 + show bleaching under selective polarized-light irradiation. Two forms of bleaching behaviour are observed. In reversible polarized bleaching, irradiation creates re-oriented equivalent centers, which can be restored to the original orientation by switching the laser polarization by 90 deg. Indefinite sequences of bleaching and recovery can be established. In photoproduct bleaching, inequivalent centers are produced, which can be reverted by subsequently selectively exciting their absorption lines. Thermal recovery of the bleached centers on warming the crystals occurs abruptly over a 5 K range around 100 K and is noteworthy in occurring at essentially identical temperatures for H - , D - and T - centers. The simplest model for this thermal recovery is thermal activation of the mobile hydrogenic ions over a double well potential barrier. An alternative model proposed by Universitaet Regensburg requires the involvement of high frequency excitations in scattering processes for surmounting the barrier

  14. Determination of the differences in oxidation potentials for the Pr3+/Pr2+ and Ce3+/Ce2+ pairs in halide melts

    International Nuclear Information System (INIS)

    Mikheev, N.B.; Auerman, L.N.; Rumer, I.A.; D'yachkova, R.A.

    1983-01-01

    Cocrystallization has been used with the (PrOCl)/sub s. ph/ - (PrCl 2 , PrCl 3 , SrCl 2 ) melt system to examine the dependence of the cerium(III) cocrystallization coefficient on the X/sub Pr 2+ /X/sub Pr 3+ / ratio in the melt. Measurement has been made in this way of the difference in oxidation potentials for the pairs Pr 3+ /Pr 2+ and Ce 3+ /Ce 2+ : ΔE/sub Pr 3+ /Pr 2+0 -E/sub Ce 3+ /Ce 2+ / 0 , which is 0.08 +/- 0.04 V for chloride

  15. The PR in PN for Education Associations. PR Bookshelf, No. 3.

    Science.gov (United States)

    National Education Association, Washington, DC.

    This booklet presents suggestions and guidelines for the effective use of public relations (PR) techniques during professional negotiations (PN) among teachers, administrators, and boards of education. Introductory sections present the National Education Association (NEA) position regarding professional negotiation and grievance procedures and…

  16. Prion protein (PrP) gene-knockout cell lines: insight into functions of the PrP

    Science.gov (United States)

    Sakudo, Akikazu; Onodera, Takashi

    2015-01-01

    Elucidation of prion protein (PrP) functions is crucial to fully understand prion diseases. A major approach to studying PrP functions is the use of PrP gene-knockout (Prnp−/−) mice. So far, six types of Prnp−/− mice have been generated, demonstrating the promiscuous functions of PrP. Recently, other PrP family members, such as Doppel and Shadoo, have been found. However, information obtained from comparative studies of structural and functional analyses of these PrP family proteins do not fully reveal PrP functions. Recently, varieties of Prnp−/− cell lines established from Prnp−/− mice have contributed to the analysis of PrP functions. In this mini-review, we focus on Prnp−/− cell lines and summarize currently available Prnp−/− cell lines and their characterizations. In addition, we introduce the recent advances in the methodology of cell line generation with knockout or knockdown of the PrP gene. We also discuss how these cell lines have provided valuable insights into PrP functions and show future perspectives. PMID:25642423

  17. Salvinorin A analogues PR-37 and PR-38 attenuate compound 48/80-induced itch responses in mice.

    Science.gov (United States)

    Salaga, M; Polepally, P R; Zielinska, M; Marynowski, M; Fabisiak, A; Murawska, N; Sobczak, K; Sacharczuk, M; Do Rego, J C; Roth, B L; Zjawiony, J K; Fichna, J

    2015-09-01

    The opioid system plays a crucial role in several physiological processes in the CNS and in the periphery. It has also been shown that selective opioid receptor agonists exert potent inhibitory action on pruritus and pain. In this study we examined whether two analogues of Salvinorin A, PR-37 and PR-38, exhibit antipruritic properties in mice. To examine the antiscratch effect of PR-37 and PR-38 we used a mouse model of compound 48/80-induced pruritus. In order to elucidate the mechanism of action of tested compounds, specific antagonists of opioid and cannabinoid receptors were used. The effect of PR-37 on the CNS was assessed by measuring motor parameters and exploratory behaviours in mice. PR-37 and PR-38, jnjected s.c., significantly reduced the number of compound 48/80-induced scratching behaviours in mice in a dose- and time-dependent manner. PR-38 was also active when orally administered. The antiscratch activity of PR-37 was blocked by the selective κ opioid receptor antagonist, nor-binaltorphimine, and that of PR-38 by the selective μ opioid receptor antagonist, β-funaltrexamine. In conclusion, a novel framework for the development of new antipruritic drugs derived from salvinorin A has been validated. © 2015 The British Pharmacological Society.

  18. Experimental Models of Inherited PrP Prion Diseases.

    Science.gov (United States)

    Watts, Joel C; Prusiner, Stanley B

    2017-11-01

    The inherited prion protein (PrP) prion disorders, which include familial Creutzfeldt-Jakob disease, Gerstmann-Sträussler-Scheinker disease, and fatal familial insomnia, constitute ∼10%-15% of all PrP prion disease cases in humans. Attempts to generate animal models of these disorders using transgenic mice expressing mutant PrP have produced variable results. Although many lines of mice develop spontaneous signs of neurological illness with accompanying prion disease-specific neuropathological changes, others do not. Furthermore, demonstrating the presence of protease-resistant PrP species and prion infectivity-two of the hallmarks of the PrP prion disorders-in the brains of spontaneously sick mice has proven particularly challenging. Here, we review the progress that has been made toward developing accurate mouse models of the inherited PrP prion disorders. Copyright © 2017 Cold Spring Harbor Laboratory Press; all rights reserved.

  19. 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

  20. Features of the advertising and PR in tourism

    OpenAIRE

    M. A. Zubarieva

    2015-01-01

    The article discusses the use of topical issues of important tools of social communication of applied tactical direction (advertising) and strategic (PR). The main types of advertising in tourism and types of PR ­ activities are characterized.The main difference between advertising and PR in the tourism sector is defined, the main attention is given to correct choice of optimal (most efficient) advertising channel (means). Specific nature, advertising issues as the main tool for the promotion...

  1. Prion propagation in cells expressing PrP glycosylation mutants.

    Science.gov (United States)

    Salamat, Muhammad K; Dron, Michel; Chapuis, Jérôme; Langevin, Christelle; Laude, Hubert

    2011-04-01

    Infection by prions involves conversion of a host-encoded cell surface protein (PrP(C)) to a disease-related isoform (PrP(Sc)). PrP(C) carries two glycosylation sites variably occupied by complex N-glycans, which have been suggested by previous studies to influence the susceptibility to these diseases and to determine characteristics of prion strains. We used the Rov cell system, which is susceptible to sheep prions, to generate a series of PrP(C) glycosylation mutants with mutations at one or both attachment sites. We examined their subcellular trafficking and ability to convert into PrP(Sc) and to sustain stable prion propagation in the absence of wild-type PrP. The susceptibility to infection of mutants monoglycosylated at either site differed dramatically depending on the amino acid substitution. Aglycosylated double mutants showed overaccumulation in the Golgi compartment and failed to be infected. Introduction of an ectopic glycosylation site near the N terminus fully restored cell surface expression of PrP but not convertibility into PrP(Sc), while PrP(C) with three glycosylation sites conferred cell permissiveness to infection similarly to the wild type. In contrast, predominantly aglycosylated molecules with nonmutated N-glycosylation sequons, produced in cells expressing glycosylphosphatidylinositol-anchorless PrP(C), were able to form infectious PrP(Sc). Together our findings suggest that glycosylation is important for efficient trafficking of anchored PrP to the cell surface and sustained prion propagation. However, properly trafficked glycosylation mutants were not necessarily prone to conversion, thus making it difficult in such studies to discern whether the amino acid changes or glycan chain removal most influences the permissiveness to prion infection.

  2. La práctica del paisajismo

    Directory of Open Access Journals (Sweden)

    Medina Muro, María

    2010-12-01

    Full Text Available The practice of landscaping is best understood by looking at who the contemporary designers are what work they do and in what professional realm they operate. If we take into account the range of possibilities a landscape architect has —from work on projects that take place in the wilderness to rural and urban environments— one can go from designing a small interior patio to projects that hace major environmental impact. Based on my knowledge and professional experience I am going to focus mainly on the types of landscapes I have been able to develop; the restoration of historic gardens, urban landscapes and private gardens, making reference to and showing examples of the works of other professionals in the field. In conclusion I will underline the importance of gardens and the relationship between ecology and the traditions of landscape design.

    La práctica del paisajismo se entiende mejor si se aclara quién es hoy un paisajista, en que ámbito profesional puede trabajar, y cuáles son sus obras. Si tenemos en cuenta la posibilidad que tiene un paisajista de actuar o participar en trabajos que abarcan tanto el paisaje natural, el rural como el urbano, su ámbito de trabajo puede ser muy amplio: desde diseñar un pequeño patio a realizar un estudio de impacto medioambiental. Me voy a referir preferentemente, y basándome en mis conocimientos y experiencia profesional, a aquellos paisajes que en la práctica he podido desarrollar: restauración de jardines y paisajes históricos; paisajes urbanos; y jardines privados, citando y mostrando algunos ejemplos de trabajos realizados por profesionales del paisaje. Por último, destacaré la importancia de los jardines y la relación entre ecología y tradición en la práctica del paisajismo. [fr] La pratique du l’aménagement paysager est mieux comprise en précisant qui est aujourd’hui un paysagiste, dans lequel cadre professionnel peut travailler, et quelles sont ses oeuvres. Si

  3. À jamais, à présent

    OpenAIRE

    Pierrepont, Alexandre

    2007-01-01

    L’objet de cet article serait de rendre compte de quelques-unes des lignes de vie de cette expérience musicale nommée « jazz », telles qu’elles se sont prolongées au cours des trois dernières décennies, particulièrement aux États-Unis. Interroger la manière avec laquelle la transmission (de parole, de présences, de jeux et d’intelligences) se fait alors et aujourd’hui, dans quelles conditions, sous quelles pressions peut-être, à partir de quels constats ou de quelles intuitions, comment en dé...

  4. (Prérif central, Maroc septentrional

    Directory of Open Access Journals (Sweden)

    Abdelghani Gartet

    2005-01-01

    Full Text Available El artículo tiene por objeto evaluar la degradación específi ca, y especialmente cuantifi car la carga de transporte sólido, en la cuenca del oued Lebène (Prérif central, caracterizada por altas tasas de erosión hídrica. La fuerte erosionabilidad de las rocas, la agresividad climática y las frecuentes variaciones de caudal hacen que el volumen de los materiales transportados por el Lebène alcancen una magnitud considerable. La irregularidad espacio-temporal de las precipitaciones y caudales condicionan el volumen de los transportes sólidos, de ahí las estrechas correlaciones existentes entre las tres variables. Los análisis relativos a la turbidez de las aguas y a la naturaleza granulométrica de los sedimentos refuerzan dicha relación.

  5. Computerbasiert prüfen [Computer-based Assessment

    Directory of Open Access Journals (Sweden)

    Frey, Peter

    2006-08-01

    Full Text Available [english] Computer-based testing in medical education offers new perspectives. Advantages are sequential or adaptive testing, integration of movies or sound, rapid feedback to candidates and management of web-based question banks. Computer-based testing can also be implemented in an OSCE examination. In e-learning environments formative self-assessment are often implemented and gives helpful feedbacks to learners. Disadvantages in high-stake exams are the high requirements as well for the quality of testing (e.g. standard setting as additionally for the information technology and especially for security. [german] Computerbasierte Prüfungen im Medizinstudium eröffnen neue Möglichkeiten. Vorteile solcher Prüfungen liegen im sequentiellen oder adaptiven Prüfen, in der Integration von Bewegtbildern oder Ton, der raschen Auswertung und zentraler Verwaltung der Prüfungsfragen via Internet. Ein Einsatzgebiet mit vertretbarem Aufwand sind Prüfungen mit mehreren Stationen wie beispielsweise die OSCE-Prüfung. Computerbasierte formative Selbsttests werden im Bereiche e-learning häufig angeboten. Das hilft den Lernenden ihren Wissensstand besser einzuschätzen oder sich mit den Leistungen anderer zu vergleichen. Grenzen zeigen sich bei den summativen Prüfungen beim Prüfungsort, da zuhause Betrug möglich ist. Höhere ärztliche Kompetenzen wie Untersuchungstechnik oder Kommunikation eigenen sich kaum für rechnergestützte Prüfungen.

  6. 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

  7. Triinu rukkileib nimetati Baltimaade parimaks PR-projektiks

    Index Scriptorium Estoniae

    2014-01-01

    Leiburi leivatehase ja kommunikatsioonibüroo Hamburg ja Partnerid ühisprojekt "Leiburi Leivategu" nimetati üleeuroopalisel pr-spetsialistide konkursil 2013. a. parimaks kommunikatsiooniprojektiks Baltimaades

  8. 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...

  9. Israel: a crise próxima

    Directory of Open Access Journals (Sweden)

    Peter DEMANT

    2014-12-01

    Full Text Available Apesar de êxitos indisputáveis, o Estado de Israel enfrenta problemas estruturais decorrentes do conflito com o mundo árabe. O texto analisa cinco vulnerabilidades subestimadas: (1 demografia: o crescimento dos ultraortodoxos e dos árabes israelenses, ambos antissionistas, que arrisca tornar minoria os judeus sionistas; (2 estratégia: novas formas de resistência usadas pelos árabes, tanto militares, como os mísseis, quanto pacíficas, como a resistência não violenta, estão progressivamente se tornando contraproducentes à ocupação israelense de territórios inimigos; (3 regional: a Primavera Árabe, apesar dos fracassos, é uma etapa na democratização e modernização das sociedades árabes que acabará erodindo a vantagem qualitativa-educacional israelense; (4 internacional: Israel depende, militar e economicamente, do apoio ocidental, mas, movidos por seus próprios desenvolvimentos demográficos e culturais, os europeus se mostram cada vez mais indiferentes ou hostis a Israel; e até nos EUA, último reduto de simpatia pró-israelense, a identificação com o Estado judaico pode se tornar mais frágil; (5 mundo judaico: devido à orientação cada vez mais particularista de Israel, há, em vez de legitimação recíproca, ameaça de alienação entre as diásporas judaicas e Israel. O artigo conclui que, a termo, as custas políticas, militares e socioculturais que a beligerância permanente impõe a Israel podem constituir um risco existencial para este país. Eventualmente, os dilemas podem se tornar perigosos para sua sobrevivência como Estado judaico.

  10. 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.)

  11. Comparative NMR study of nPrBTP and iPrBTP

    Energy Technology Data Exchange (ETDEWEB)

    Adam, C.; Muellich, U.; Geist, A.; Geckeis, H. [Karlsruhe Institute of Technology - KIT, Institute for Nuclear Waste Disposal - INE, Herrmann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany); Rohde, V. [Fraunhofer Institute for Chemical Technology - ICT, Environmental Engineering, Joseph-von-Fraunhofer-Str. 7, 76327 Pfinztal (Germany); Kaden, P. [Helmholtz-Zentrum Dresden - Rossendorf e. V., Institute of Resource Ecology, Bautzner Landstrasse 400, 01328 Dresden (Germany); Panak, P.J. [Karlsruhe Institute of Technology - KIT, Institute for Nuclear Waste Disposal - INE, Herrmann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany); University of Heidelberg, Department of Physical Chemistry, Im Neuenheimer Feld 253, 69120 Heidelberg (Germany)

    2016-07-01

    Bis-triazinyl-pyridine type ligands are important extracting agents for separating trivalent actinide ions from trivalent lanthanides. The alkyl substituents on the lateral triazine rings have a significant effect on the stability of the ligand against hydrolysis and radiolysis. Furthermore they influence solubility, extraction behaviour and selectivity. TRLFS and extraction studies suggest differences in complexation and extraction behaviour of BTP ligands bearing iso-propyl or n-propyl substituents, respectively. As NMR studies allow insight into the metal-ligand bonding, we conducted NMR studies on a range of {sup 15}N-labelled nPrBTP and iPrBTP Ln(III) and Am(III) complexes. Our results show that no strong change in the metal-ligand bonding occurs, thus excluding electronic reasons for differences in complexation behaviour, extraction kinetics and selectivity. This supports mechanistic reasons for the observed differences. (authors)

  12. Teoria e prática das práticas alternativas

    Directory of Open Access Journals (Sweden)

    Fernando D. de Avila-Pires

    1995-04-01

    Full Text Available São abordados, os fundamentos científicos e a ética da utilização das práticas de medicina alternativa em voga no Brasil. Ressalta-se que, em geral, o termo alternativo não é definido e que pode se referir aos princípios básicos ou aos métodos de diagnóstico e tratamento. Sugere-se que a escolha individual de um sistema terapêutico é mais influenciada por fatores culturais, pela tradição familiar e pela moda, do que pela análise racional dos seus fundamentos. Estabelece-se que o que distingue realmente os diferentes sistemas são seus princípios e não suas práticas.

  13. Teoria e prática das práticas alternativas

    Directory of Open Access Journals (Sweden)

    Avila-Pires Fernando D. de

    1995-01-01

    Full Text Available São abordados, os fundamentos científicos e a ética da utilização das práticas de medicina alternativa em voga no Brasil. Ressalta-se que, em geral, o termo alternativo não é definido e que pode se referir aos princípios básicos ou aos métodos de diagnóstico e tratamento. Sugere-se que a escolha individual de um sistema terapêutico é mais influenciada por fatores culturais, pela tradição familiar e pela moda, do que pela análise racional dos seus fundamentos. Estabelece-se que o que distingue realmente os diferentes sistemas são seus princípios e não suas práticas.

  14. Présentation du volume

    Directory of Open Access Journals (Sweden)

    Ana Zwitter Vitez

    2012-12-01

    Full Text Available Dans de nombreuses disciplines scientifiques, le discours parlé représente depuis quelques décennies un objet de recherche proéminent. Ce fait s’explique probablement par deux caractéristiques principales du discours parlé: la structure complexe de sa matérialité et les fonctions variées de différentes pratiques langagières. C’est pourquoi le présent numéro réunit les articles basés sur les approches actuelles du discours parlé et sur les pratiques langagières spécifiques. Le volume est introduit par deux articles interdisciplinaires: Peter Garrard et Ahmed Samrah présentent le domaine de la pathologie du langage en donnant une revue fouillée sur les approches actuelles de l’analyse linguistique lors de la détection de la maladie d’Alzheimer, tandis que Harry Hollien donne un aperçu structuré sur le domaine de la phonétique judiciaire destiné à dévoiler l’identité des locuteurs et de détecter la déception dans le discours parlé. Les analyses explorant l’acquisition du langage commencent par l’article de Katharina Zipser qui examine la progression de structures grammaticales en les mettant en comparaison avec la compétence des apprenants et continuent par l’étude de Meta Lah proposant une évaluation des documents audiovisuels proposés aux apprenants de langue étrangère. Vesna Požgaj Hadži, Damir Horga et Tatjana Balažic Bulc remettent en question la corrélation entre la compétence linguistique et la fluence linguistique auprès de locuteurs non-maternels et l'analyse de Gemma Santiago Alonso aborde l'acquisition de l'article défini dans le langage enfantin. Les articles suivants se réunissent autour du domaine de l'interprétation: Jana Zidar Forte présente une approche actuelle dans l'entrainement d'interprètes, Lea Burjan analyse les phénomènes issus de la pratique de l'interprétation juridique et Simona  Šumrada traite de la reformulation dans le discours de la traduction et de

  15. Small protease sensitive oligomers of PrPSc in distinct human prions determine conversion rate of PrP(C.

    Directory of Open Access Journals (Sweden)

    Chae Kim

    Full Text Available The mammalian prions replicate by converting cellular prion protein (PrP(C into pathogenic conformational isoform (PrP(Sc. Variations in prions, which cause different disease phenotypes, are referred to as strains. The mechanism of high-fidelity replication of prion strains in the absence of nucleic acid remains unsolved. We investigated the impact of different conformational characteristics of PrP(Sc on conversion of PrP(C in vitro using PrP(Sc seeds from the most frequent human prion disease worldwide, the Creutzfeldt-Jakob disease (sCJD. The conversion potency of a broad spectrum of distinct sCJD prions was governed by the level, conformation, and stability of small oligomers of the protease-sensitive (s PrP(Sc. The smallest most potent prions present in sCJD brains were composed only of∼20 monomers of PrP(Sc. The tight correlation between conversion potency of small oligomers of human sPrP(Sc observed in vitro and duration of the disease suggests that sPrP(Sc conformers are an important determinant of prion strain characteristics that control the progression rate of the disease.

  16. 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

  17. Biro Konsultan PR dan Kompetensi Praktisi PR di Era Industrialisasi Komunikasi dan Pencitraan

    Directory of Open Access Journals (Sweden)

    Dina Sekar Vusparatih

    2013-04-01

    Full Text Available The world of communication starts to experience rapid development in various aspects of life, almost all over the world. In Indonesia, it is marked by the emergence of a lot of tv and radio stations, and started the trend of imaging strategy efforts that is used to win the regional election, nasional election, and even to win marketing competition through company’s products or services image branding. This phenomenon is the opportunity for PR consultants to be successful team in designing appropriate communication strategies and appropriate steps to build the image. This opportunity is used by many people which is characterized by the proliferation of consultancies. Competition between consultants becomes so tight considering the companies or organizations that intend to hire consultants also want the best. Competitive bidding process was conducted, to win this, it needs solid team of consultants required in skills and morally. PR competencies of each member are needed to grow into a successful PR consultant. 

  18. RIZ Tumor and Breast Cancer: The PR Domain

    National Research Council Canada - National Science Library

    Aznar-Derunes, Celine

    2005-01-01

    .... RIZ is the founding member of the PR-domain family of zinc finger genes. Two protein products are produced from the RIZ gene which differ by the presence or the absence of the PR domain: RIZ1 and RIZ2...

  19. Case Studies in e-RPL and e-PR

    Science.gov (United States)

    Cameron, Roslyn; Miller, Allison

    2014-01-01

    The use of ePortfolios for recognition of prior learning (e-RPL) and for professional recognition (e-PR) is slowly gaining in popularity in the VET sector however their use is sporadic across educational sectors, disciplines, educational institutions and professions. Added to this is an array of purposes and types of e-RPL and e-PR models and…

  20. 33 CFR 161.20 - Position Report (PR).

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Position Report (PR). 161.20 Section 161.20 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED... Report (PR). A vessel must report its name and position: (a) Upon point of entry into a VMRS area; (b) At...

  1. RIZ Tumor Suppressor and Breast Cancer: The PR Domain

    National Research Council Canada - National Science Library

    Aznar-Derunes, Celine

    2004-01-01

    .... RIZ is the founding member of the PR-domain family of zinc finger genes. Two protein products are produced from the RIZ gene which differ by the presence or the absence of the PR domain : RIZ1 and RIZ2...

  2. 75 FR 2165 - Puerto Rico Disaster No. PR-00007

    Science.gov (United States)

    2010-01-14

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration Nos. 12004 and 12005; Puerto Rico Disaster No. PR-00007] Puerto Rico Disaster No. PR-00007 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY: This is a notice of an Administrative declaration of a disaster for the Commonwealth of...

  3. The role of e-PR in foreign policy

    Directory of Open Access Journals (Sweden)

    Tereshchuk Vitaliy Ivanovych

    2015-10-01

    Full Text Available The article discusses the role of the Internet as a global communication tool in the PR-support of the implementation of foreign policy. Special attention is paid to such innovative directions of electronic foreign PR as the creation of "virtual embassies" (on the example of the United States.

  4. Incorporation of Pr into LuAG ceramics

    Science.gov (United States)

    Marchewka, M. R.; Chapman, M. G.; Qian, H.; Jacobsohn, L. G.

    2017-06-01

    An investigation of the effects of Pr in (Lu1-xPrx)3Al5O12 (LuAG:Pr) ceramics was carried out by means of x-ray diffraction (XRD), energy dispersive x-ray spectroscopy (EDX), and attenuated total reflection Fourier transform infrared spectroscopy (ATR FTIR) measurements coupled with luminescence measurements. It was found that the Pr concentration that maximizes luminescence emission depends on the thermal processing conditions. While the calcined LuAG:Pr powder showed maximum luminescence emission for Pr concentrations between 0.18 and 0.33 at.%, maximum emission of ceramic bodies sintered at 1500 °C for 20 h was obtained with Pr concentrations between 0.018 and 0.18 at.%. Further, for short sintering times up to about 3 h, luminescence emission intensity is maximum for Pr concentrations around 0.33 at.%. Longer sintering times lead to the formation of PrAlO3 as a secondary phase, concomitant with a reduction of the intensity of luminescence emission.

  5. Antimicrobial and immunomodulatory activities of PR-39 derived peptides.

    Directory of Open Access Journals (Sweden)

    Edwin J A Veldhuizen

    Full Text Available The porcine cathelicidin PR-39 is a host defence peptide that plays a pivotal role in the innate immune defence of the pig against infections. Besides direct antimicrobial activity, it is involved in immunomodulation, wound healing and several other biological processes. In this study, the antimicrobial- and immunomodulatory activity of PR-39, and N- and C-terminal derivatives of PR-39 were tested. PR-39 exhibited an unexpected broad antimicrobial spectrum including several Gram positive strains such as Bacillus globigii and Enterococcus faecalis. Of organisms tested, only Staphylococcus aureus was insensitive to PR-39. Truncation of PR-39 down to 15 (N-terminal amino acids did not lead to major loss of activity, while peptides corresponding to the C-terminal part of PR-39 were hampered in their antimicrobial activity. However, shorter peptides were all much more sensitive to inhibition by salt. Active peptides induced ATP leakage and loss of membrane potential in Bacillus globigii and Escherichia coli, indicating a lytic mechanism of action for these peptides. Finally, only the mature peptide was able to induce IL-8 production in porcine macrophages, but some shorter peptides also had an effect on TNF-α production showing differential regulation of cytokine induction by PR-39 derived peptides. None of the active peptides showed high cytotoxicity highlighting the potential of these peptides for use as an alternative to antibiotics.

  6. Antimicrobial and Immunomodulatory Activities of PR-39 Derived Peptides

    Science.gov (United States)

    Veldhuizen, Edwin J. A.; Schneider, Viktoria A. F.; Agustiandari, Herfita; van Dijk, Albert; Tjeerdsma-van Bokhoven, Johanna L. M.; Bikker, Floris J.; Haagsman, Henk P.

    2014-01-01

    The porcine cathelicidin PR-39 is a host defence peptide that plays a pivotal role in the innate immune defence of the pig against infections. Besides direct antimicrobial activity, it is involved in immunomodulation, wound healing and several other biological processes. In this study, the antimicrobial- and immunomodulatory activity of PR-39, and N- and C-terminal derivatives of PR-39 were tested. PR-39 exhibited an unexpected broad antimicrobial spectrum including several Gram positive strains such as Bacillus globigii and Enterococcus faecalis. Of organisms tested, only Staphylococcus aureus was insensitive to PR-39. Truncation of PR-39 down to 15 (N-terminal) amino acids did not lead to major loss of activity, while peptides corresponding to the C-terminal part of PR-39 were hampered in their antimicrobial activity. However, shorter peptides were all much more sensitive to inhibition by salt. Active peptides induced ATP leakage and loss of membrane potential in Bacillus globigii and Escherichia coli, indicating a lytic mechanism of action for these peptides. Finally, only the mature peptide was able to induce IL-8 production in porcine macrophages, but some shorter peptides also had an effect on TNF-α production showing differential regulation of cytokine induction by PR-39 derived peptides. None of the active peptides showed high cytotoxicity highlighting the potential of these peptides for use as an alternative to antibiotics. PMID:24755622

  7. PrP-C1 fragment in cattle brains reveals features of the transmissible spongiform encephalopathy associated PrPsc.

    Science.gov (United States)

    Serra, Fabienne; Müller, Joachim; Gray, John; Lüthi, Ramona; Dudas, Sandor; Czub, Stefanie; Seuberlich, Torsten

    2017-03-15

    Three different types of bovine spongiform encephalopathy (BSE) are known and supposedly caused by distinct prion strains: the classical (C-) BSE type that was typically found during the BSE epidemic, and two relatively rare atypical BSE types, termed H-BSE and L-BSE. The three BSE types differ in the molecular phenotype of the disease associated prion protein, namely the N-terminally truncated proteinase K (PK) resistant prion protein fragment (PrP res ). In this study, we report and analyze yet another PrP res type (PrP res-2011 ), which was found in severely autolytic brain samples of two cows in the framework of disease surveillance in Switzerland in 2011. Analysis of brain tissues from these animals by PK titration and PK inhibitor assays ruled out the process of autolysis as the cause for the aberrant PrP res profile. Immunochemical characterization of the PrP fragments present in the 2011 cases by epitope mapping indicated that PrP res-2011 corresponds in its primary sequence to the physiologically occurring PrP-C1 fragment. However, high speed centrifugation, sucrose gradient assay and NaPTA precipitation revealed biochemical similarities between PrP res-2011 and the disease-associated prion protein found in BSE affected cattle in terms of detergent insolubility, PK resistance and PrP aggregation. Although it remains to be established whether PrP res-2011 is associated with a transmissible disease, our results point out the need of further research on the role the PrP-C1 aggregation and misfolding in health and disease. Copyright © 2017. Published by Elsevier B.V.

  8. Energy transfer between Pr3+ and Mn2+ in K2YZr(PO4)3: Pr, Mn phosphor

    International Nuclear Information System (INIS)

    Liang Wei; Wang Yuhua

    2011-01-01

    Research highlights: → Pr 3+ , Mn 2+ co-doped K 2 YZr(PO 4 ) 3 phosphor is a novel type of practical visible quantum cutting phosphor in promising application. → The optimal quantum efficiency (QE) of this co-doped system K 2 YZr(PO 4 ) 3 : Pr 3+ , Mn 2+ reached to 126.3%. → The Mn 2+6 A 1g → 4 E g - 4 A 1g transition was found to coincide well with the 1 S 0 → 1 I 6 transition of Pr 3+ . → The energy transfer from Pr 3+ to Mn 2+ was also observed, converting the first photon from the PCE of Pr 3+ into the red emission of Mn 2+ , and the QC process occurred in this Pr 3+ , Mn 2+ co-doped K 2 YZr(PO 4 ) 3 phosphor. - Abstract: Pr 3+ , Mn 2+ co-doped K 2 YZr(PO 4 ) 3 samples were prepared by solid-state reaction method and their photoluminescence (PL) properties were investigated in ultra-violet (UV) and vacuum ultra-violet (VUV) region. The results indicated that in Pr 3+ singly doped K 2 YZr(PO 4 ) 3 sample, the first-step transition ( 1 S 0 → 1 I 6 , 3 P J around 405 nm) of Pr 3+ is near the ultraviolet (UV) range, not useful for practical application. When Mn 2+ was doped as a co-activator ion, the energy of 1 S 0 → 1 I 6 , 3 P J transition can be transferred synchronously from Pr 3+ to Mn 2+ and then emit a visible photon. The optimal quantum efficiency (QE) of this co-doped system K 2 YZr(PO 4 ) 3 : Pr 3+ , Mn 2+ reached to 126.3%, suggesting a novel type of practical visible quantum cutting phosphor in promising application.

  9. Digitale prøver – et litteraturstudie

    Directory of Open Access Journals (Sweden)

    Karen Louise Møller

    2015-10-01

    Full Text Available Digitale prøveformer bliver efterhånden mere og mere udbredte. Denne artikel er baseret på et litteraturstudie foretaget for at få indsigt i primært forskningslitteraturen om digitale prøveformer. I artiklen præsenterer vi de forskellige typer digitale prøver, der omtales og diskuteres i litteraturen, og vi beskriver de potentielle fordele af bl.a. økonomisk, administrativ og pædagogisk karakter, der ifølge litteraturen kan opnås ved at bruge digitale prøver. Vi beskriver endvidere de udfordringer og potentielle ulemper, der kan være forbundet med indførelse af digitale prøver. Det drejer sig bl.a. om udfordringer hvad angår prøvesystem, organisation, teknologi, kompetenceudvikling og uddannelseskultur. Vi beskriver i artiklen en række konkrete eksempler på digitale prøver, og vi præsenterer resultater fra undersøgelser af underviseres og studerendes oplevelser med digitale prøveformer. Against the backdrop of the rapid spread of digitized tests and exams, this article sets out to present some of the results of a literature study carried out with the aim of gaining insight into the research literature on this topic. The article presents different types of tests, focusing on the financial, administrative, and pedagogical advantages described and discussed in the literature as potentially attainable through the use of digitized exams. In addition, the challenges and potential problems connected with the introduction of digitized tests are described. Among these are challenges related to the test system or to competence development as well as organizational, technological, and cultural challenges. Finally, the article provides concrete descriptions of tests and presents results from select studies of teacher and student experiences of digitized tests.

  10. ER and PR expression and survival after endometrial cancer.

    Science.gov (United States)

    Smith, Deborah; Stewart, Colin J R; Clarke, Edward M; Lose, Felicity; Davies, Claire; Armes, Jane; Obermair, Andreas; Brennan, Donal; Webb, Penelope M; Nagle, Christina M; Spurdle, Amanda B

    2018-02-01

    To measure association between endometrial carcinoma ER and PR status and endometrial cancer (EC) survival, accounting for inter-observer variation. The intensity and proportion of tumor cell expression of ER and PR in ECs were assessed independently and semi-quantitatively by two pathologists using digital images of duplicate tumor tissue microarrays (TMAs). Cases with inconsistent initial assessment were reviewed and final scoring agreed. The association between overall and EC-specific survival and hormone receptor expression (intensity, proportion and combined) was assessed using Cox regression analysis. The C-index was used to evaluate model discrimination with addition of ER and PR status. Tumor ER and PR analysis was possible in 659 TMAs from 255 patients, and in 459 TMAs from 243 patients, respectively. Initial ER and PR scoring was consistent in 82% and 80% of cases, respectively. In multivariate analyses decreased ER and PR expression was associated with increased tumor-related mortality. Associations reached statistical significance for ER proportion score (P=0.05), ER intensity score (P=0.003), and PR combined score (P=0.04). Decreased expression of combined ER/PR expression was associated with poorer EC-specific survival than decreased expression of either hormone receptor alone (P=0.005). However, hormone receptor status did not significantly improve mortality prediction in individual cases. ER and PR expression combined, using cut-points that capture variation in scoring and across cores, is significantly associated with EC-specific survival in analyses adjusting for known prognostic factors. However, at the individual level, ER and PR expression does not improve mortality prediction. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Test og prøvelser

    DEFF Research Database (Denmark)

    Test i forskellige former og afskygninger spiller i dag en markant rolle indenfor mange forskellige områder i samfundet. De bliver anvendt til at evaluere og bedømme børn, unge og voksne i forskellige kontekster og med forskellige formål og konsekvenser. I mange tilfælde er der tale om test, hvis...... udfald – direkte eller indirekte - vil kunne få vidtrækkende følger for dem, der testes. Test kan sætte sig spor livet igennem og udsætte de testede for prøvelser, idet de påvirker deres selvopfattelser og udstikker bestemte livsbaner og muligheder. Med afsæt i uddannelsesområdet sætter denne bog fokus...... på test i historisk og nutidig belysning. Den behandler spørgsmål som: Hvordan kom test ind i feltet? Hvilke test anvendes? Hvem tester man? Hvorfor vil man gerne teste? Hvad er de direkte og indirekte sociale konsekvenser af at anvende test? Besvarelsen af disse spørgsmål kan på den ene side bidrage...

  12. (Prérif Central, Maroc septentrional

    Directory of Open Access Journals (Sweden)

    Abdelghani Gartet

    2006-01-01

    Full Text Available El diapiro de sal de Tissa, situado en el Prerif central marroquí, afl ora en una zona de contacto estructural anormal donde la morfogénesis kárstica es muy activa. La solubilidad de las formaciones del complejo triásico es excesivamente fuerte. El macizo yesífero-salino representa un yacimiento de sal gema casi inagotable. Sin embargo, las aguas de Oued Lebène, en época de crecidas, socavan intensamente la base del macizo y terminan siendo afectadas por la contaminación química. La explotación de la cantera de sal, siendo tradicional, plantea numerosos problemas de planifi cación, a la vez que atenta severamente contra el medio ambiente (natural y urbano y contra la sociedad humana. Las medidas de defensa del medio ambiente adoptadas al respecto resultan por el momento insufi cientes dada la falta de una legislación práctica y rigurosa.

  13. The Japanese PR and PP program

    International Nuclear Information System (INIS)

    Senzaki, Masao; Inoue, Naoko; Kuno, Yusuke

    2008-01-01

    Japan has established the commercial nuclear fuel cycle with LWR as a non-weapon state, and now has been developing RF fuel cycle as the next generation technology. Japanese studies on proliferation resistance have started in 1990's by JNC, predecessor concern of JAEA. The early study was focused on the intrinsic features of Pu and safeguards technologies. Based on TOPS report, JNC has developed a quantitative assessment methodology and modified it by JNC designers. JNC and JAEA intends to play the role as a hub that contributes international collaborative study such as GEN IV PR and PP Experts Group and INPRO based on Japanese experiences of safeguards and nonproliferation efforts, and feedback to domestic experts. These efforts include not only the contribution into those programs, but also introduce these activities to Japanese domestic experts, holding international workshops, symposiums as a 'Hub' of domestic and international experts. This paper will introduce the Japanese Proliferation Resistance studies including, the early studies, international workshops/symposiums, the study in FaCT, international collaboration studies, and the future direction identified for the nuclear fuel cycle systems. (author)

  14. 77 FR 68102 - Foreign-Trade Zone 163-Ponce, PR; Application for Subzone; Zimmer Manufacturing BV; Ponce, PR

    Science.gov (United States)

    2012-11-15

    ... DEPARTMENT OF COMMERCE Foreign-Trade Zones Board [B-81-2012] Foreign-Trade Zone 163--Ponce, PR; Application for Subzone; Zimmer Manufacturing BV; Ponce, PR An application has been submitted to the Foreign-Trade Zones Board (the Board) by CODEZOL, C.D., grantee of FTZ 163, requesting special- purpose subzone...

  15. 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

  16. PrEP Whores and HIV Prevention: The Queer Communication of HIV Pre-Exposure Prophylaxis (PrEP).

    Science.gov (United States)

    Spieldenner, Andrew

    2016-12-01

    HIV pre-exposure prophylaxis (PrEP) has been introduced as another biomedical tool in HIV prevention. Whereas other such tools-including post-exposure prophylaxis (PEP) and interruption of perinatal transmission-have been embraced by those impacted by HIV, PrEP has been met with more conflict, especially within the gay community and HIV organizations. The "PrEP whore" has come to designate the social value and personal practices of those taking PrEP. This study examines the "PrEP whore" discourse by using queer theory and quare theory. Within these theoretical vantage points, the study explicates four discursive areas: slut shaming, dirty/clean binaries, mourning the loss of condoms, and reclaiming the inner whore. The study illuminates possible discursive strategies that lie outside of the domains of public health and within the individual and community.

  17. On the nature of the dhcp to fcc transition under pressure in Pr and Pr-Th alloys

    International Nuclear Information System (INIS)

    Vijayakumar, V.; Godwal, B.K.; Sikka, S.K.; Chidambaram, R.

    1988-01-01

    The results of electrical resistance (R), thermoelectric power (TEP) and X-ray diffraction measurements on praseodymium (Pr) and its alloys with thorium under pressure are reported. The maximum in R vs P curve exhibited by Pr persists only in the dhcp phase of Pr-Th alloy. X-ray measurements confirmed that in the alloys also the maximum in R vs P curve is due to the dhcp → fcc transition. Thus the behaviour of Pr and Pr-Th alloys is different from that of La and its alloys with Ce and Th where the maximum in the R vs P curve is electronic in origin and is exhibited by the dhcp, fcc and dist fcc phases. (author). 14 refs

  18. 75 FR 51531 - Proposed Collection; Comment Request for Forms 941, 941-PR, 941-SS, 941-X, 941-X(PR), Schedule B...

    Science.gov (United States)

    2010-08-20

    ... 941, 941-PR, 941- SS, 941-X, 941-X(PR), Schedule B (Form 941), Schedule R (Form 941) and Schedule B (Form 941-PR) AGENCY: Internal Revenue Service (IRS), Treasury. ACTION: Notice and request for comments... comments concerning Forms 941 (Employer's Quarterly Federal Tax Return), 941-PR (Planilla Para La...

  19. 78 FR 47056 - Proposed Collection; Comment Request for Forms 941, 941-PR, 941-SS, 941-X, 941-X(PR), Schedule B...

    Science.gov (United States)

    2013-08-02

    ... 941, 941-PR, 941- SS, 941-X, 941-X(PR), Schedule B (Form 941), Schedule R (Form 941)and Schedule B (Form 941-PR) AGENCY: Internal Revenue Service (IRS), Treasury. ACTION: Notice and request for comments... Forms 941 (Employer's Quarterly Federal Tax Return), 941-PR, 941-SS (Employer's Quarterly Federal Tax...

  20. Plant Reliability - an Integrated System for Management (PR-ISM)

    International Nuclear Information System (INIS)

    Aukeman, M.C.; Leininger, E.G.; Carr, P.

    1984-01-01

    The Toledo Edison Company, located in Toledo, Ohio, United States of America, recently implemented a comprehensive maintenance management information system for the Davis-Besse Nuclear Power Station. The system is called PR-ISM, meaning Plant Reliability - An Integrated System for Management. PR-ISM provides the tools needed by station management to effectively plan and control maintenance and other plant activities. The PR-ISM system as it exists today consists of four integrated computer applications: equipment data base maintenance, maintenance work order control, administrative activity tracking, and technical specification compliance. PR-ISM is designed as an integrated on-line system and incorporates strong human factors features. PR-ISM provides each responsible person information to do his job on a daily basis and to look ahead towards future events. It goes beyond 'after the fact' reporting. In this respect, PR-ISM is an 'interactive' control system which: captures work requirements and commitments as they are identified, provides accurate and up-to-date status immediately to those who need it, simplifies paperwork and reduces the associated time delays, provides the information base for work management and reliability analysis, and improves productivity by replacing clerical tasks and consolidating maintenance activities. The functional and technical features of PR-ISM, the experience of Toledo Edison during the first year of operation, and the factors which led to the success of the development project are highlighted. (author)

  1. Selective recognition of Pr3+ based on fluorescence enhancement sensor

    International Nuclear Information System (INIS)

    Ganjali, M.R.; Hosseini, M.; Ghafarloo, A.; Khoobi, M.; Faridbod, F.; Shafiee, A.; Norouzi, P.

    2013-01-01

    (E)-2-(1-(4-hydroxy-2-oxo-2H-chromen-3-yl)ethylidene) hydrazinecarbothioamide (L) has been used to detect trace amounts of praseodymium ion in acetonitrile–water solution (MeCN/H 2 O) by fluorescence spectroscopy. The fluorescent probe undergoes fluorescent emission intensity enhancement upon binding to Pr 3+ ions in MeCN/H 2 O (9/1:v/v) solution. The fluorescence enhancement of L is attributed to a 1:1 complex formation between L and Pr 3+ , which has been utilized as the basis for selective detection of Pr 3+ . The sensor can be applied to the quantification of praseodymium ion with a linear range of 1.6 × 10 −7 to 1.0 × 10 −5 M. The limit of detection was 8.3 × 10 −8 M. The sensor exhibits high selectivity toward praseodymium ions in comparison with common metal ions. The proposed fluorescent sensor was successfully used for determination of Pr 3+ in water samples. - Highlights: • A new fluorescent sensor is introduced as a selective probe for Pr 3+ detection. • Fluorescent intensity of the chemical probe enhances upon binding to Pr 3+ ion. • The sensor can be used for Pr 3+ determination in the range of 1.6 × 10 −7 –1.0 × 10 −5 M

  2. Las prácticas en el contexto comunicativo

    Directory of Open Access Journals (Sweden)

    Guillermo Orozco Gómez

    2015-01-01

    Full Text Available La comunicación debe ser entendida como proceso y producto de diversas prácticas sociales, cuyos componentes básicos son la sociabilidad, la ritualidad y la tecnicidad. Desde una perspectiva democrática, esas prácticas deben ser fortalecidas, especialmente en uno de sus aspectos esenciales: el diálogo y los "escenarios para ese diálogo". Actualmente el desafío radica en el fortalecimiento de las prácticas sociales -autónomas y democráticas- y especialmente de la comunicación, producto y componente de ellas.

  3. Athletes as PR Spokespeople: the NFL’s “A Crucial Catch” PR Campaign Explored

    Directory of Open Access Journals (Sweden)

    Chyna Teresa Trible

    2015-06-01

    Full Text Available The results of the present study were presented at the 2015 International Conference on Communication and Management and examined the National Football League’s (NFL “A Crucial Catch” breast cancer awareness campaign in the United States. Variables included identification with NFL athletes, exposure to the campaign, NFL fanship, and intention to schedule a breast cancer screening (the action promoted by NFL athletes in this PR campaign. Social media outlets and an e-mail listserv of the School of Communication at Rochester Institute of Technology in Rochester, New York, USA were employed to solicit participants (n=119 in a survey. A questionnaire composed of items modified from Brown and Bocarnea’s (2007a Celebrity-Persona Parasocial Identification Scale to investigate identification with NFL athletes was used. Statistically significant relationships were found between identification with NFL athletes and exposure, identification with NFL athletes and intention to schedule a breast cancer screening, and identification with NFL athletes and NFL fanship. NFL fanship was also significantly related to exposure to the campaign. Implications for future studies analyzing PR campaigns produced by the NFL and FIFA are suggested.

  4. Infectivity-associated PrP(Sc) and disease duration-associated PrP(Sc) of mouse BSE prions.

    Science.gov (United States)

    Miyazawa, Kohtaro; Okada, Hiroyuki; Masujin, Kentaro; Iwamaru, Yoshifumi; Yokoyama, Takashi

    2015-01-01

    Disease-related prion protein (PrP(Sc)), which is a structural isoform of the host-encoded cellular prion protein, is thought to be a causative agent of transmissible spongiform encephalopathies. However, the specific role of PrP(Sc) in prion pathogenesis and its relationship to infectivity remain controversial. A time-course study of prion-affected mice was conducted, which showed that the prion infectivity was not simply proportional to the amount of PrP(Sc) in the brain. Centrifugation (20,000 ×g) of the brain homogenate showed that most of the PrP(Sc) was precipitated into the pellet, and the supernatant contained only a slight amount of PrP(Sc). Interestingly, mice inoculated with the obtained supernatant showed incubation periods that were approximately 15 d longer than those of mice inoculated with the crude homogenate even though both inocula contained almost the same infectivity. Our results suggest that a small population of fine PrP(Sc) may be responsible for prion infectivity and that large, aggregated PrP(Sc) may contribute to determining prion disease duration.

  5. 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...

  6. Paramagnetic probes to study PrNi5?

    International Nuclear Information System (INIS)

    Hutchinson, W.D.; Harker, S.J.; Stewart, G.A.; Chaplin, D.H.; Kaplan, N.

    1996-01-01

    The Van-Vleck paramagnet PrNi 5 has been the focus of many studies in the past as a result of its usefulness as a nuclear cooling agent. Extensive continuous wave praseodymium NMR measurements have been carried out on this compound. However pulsed NMR and therefore precise relaxation measurements particularly at mK temperatures have proved elusive. In this work we have proposed to use radiative gamma-ray detection to indirectly measure Pr NMR in PrNi 5 via cross relaxation to suitable paramagnetic impurity probes placed at Ni lattice sites. 57 Co was chosen as the most compatible nuclear orientation isotope with an appropriate nuclear g-factor. The choice of 57 Co also allows the use of Moessbauer spectroscopy to check the site occupancy. This poster details the production of a 57 Co doped PrNi 5 single crystal specimen including the specimen preparation problems encountered, 57 Fe Moessbauer and preliminary nuclear orientation measurements

  7. 75 FR 68393 - Puerto Rico Disaster # PR-00011

    Science.gov (United States)

    2010-11-05

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12366 and 12367] Puerto Rico Disaster PR-00011 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY: This is a notice of an Administrative declaration of a disaster [[Page 68394

  8. High Ra, high Pr convection with viscosity gradients

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. High Ra, high Pr convection with viscosity gradients. Weak upward flow through mesh. Top fluid more viscous. Unstable layer Instability Convection.

  9. Study of positive parity bands in 137Pr

    International Nuclear Information System (INIS)

    Agarwal, Priyanka; Kumar, Suresh; Jain, A.K.; Singh, Sukhjeet; Malik, S.S.; Sinha, Rishi Kumar; Dhal, Anukul; Chaturvedi, L.; Muralithar, S.; Singh, R.P.; Madhavan, N.; Kumar, Rakesh; Bhowmik, R.K.; Pancholi, S.C.; Jain, H.C.

    2006-01-01

    In this paper the analysis and interpretation of the positive parity states in 137 Pr have been reported. The detailed interpretation with configuration assignments and the calculations for the bands will be reported

  10. Characterization and optical properties of Pr2O3-doped ...

    Indian Academy of Sciences (India)

    2017-06-09

    Jun 9, 2017 ... Pr3+ doped molybdenum lead-borate glasses with the chemical ... Thermal, optical and structural analyses are carried out using DSC, UV and FTIR spectra. ... energy band gap (Egopt), of these glasses have been determined.

  11. PrEP implementation research in Africa: what is new?

    Science.gov (United States)

    Cowan, Frances M; Delany-Moretlwe, Sinead; Sanders, Eduard J; Mugo, Nelly R; Guedou, Fernand A; Alary, Michel; Behanzin, Luc; Mugurungi, Owen; Bekker, Linda-Gail

    2016-01-01

    Of the two million new HIV infections in adults in 2014, 70% occurred in sub-Saharan Africa. Several African countries have already approved guidelines for pre-exposure prophylaxis (PrEP) for individuals at substantial risk of HIV as part of combination HIV prevention but key questions remain about how to identify and deliver PrEP to those at greatest need. Throughout the continent, individuals in sero-discordant relationships, and members of key populations (sex workers, men who have sex with men (MSM), transgender women and injection drug users) are likely to benefit from the availability of PrEP. In addition, adolescent girls and young women (AGYW) are at substantial risk in some parts of the continent. It has been estimated that at least three million individuals in Africa are likely to be eligible for PrEP according to WHO's criteria. Tens of demonstration projects are planned or underway across the continent among a range of countries, populations and delivery settings. In each of the target populations, there are overarching issues related to (i) creating demand for PrEP, (ii) addressing supply-side issues and (iii) providing appropriate and tailored adherence support. Critical for creating demand for PrEP is the normalization of HIV prevention. Community-level interventions which engage opinion leaders as well as empowerment interventions for those at highest risk will be key. Critical to supply of PrEP is that services are accessible for all, including for stigmatized populations. Establishing accessible integrated services provides the opportunity to address other public health priorities including the unmet need for HIV testing, contraception and sexually transmitted infections treatment. National policies need to include minimum standards for training and quality assurance for PrEP implementation and to address supply chain issues. Adherence support needs to recognize that social and structural factors are likely to have an important influence

  12. 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)

  13. 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)

  14. Complejidad versus simplicidad en prótesis total removible

    OpenAIRE

    Escuin Henar, Tomás J. (Tomás José); Ferré de Guilarte, Antonio; Gascón Mayordomo, Francisco; Salsench Cabré, Juan

    1992-01-01

    En el presente trabajo valoramos los resultados a distancia (dos años) del método de elaboración de la Prótesis Total Removible, mediante la utilización de parámetros clínicos, con el fin de simplificar el proceso de elaboración de la Prótesis Total.

  15. Thermodynamic database for the Co-Pr system.

    Science.gov (United States)

    Zhou, S H; Kramer, M J; Meng, F Q; McCallum, R W; Ott, R T

    2016-03-01

    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.

  16. Incommensurate magnetic ordering of PrPdAl

    Energy Technology Data Exchange (ETDEWEB)

    Keller, L. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Doenni, A. [National Research Inst. for Metals, Tsukuba, Ibaraki (Japan). Tsukuba Lab.; Fauth, F. [Institut Max von Laue - Paul Langevin, 75 - Paris (France)

    1997-09-01

    The intermetallic rare earth compound PrPdAl with ZrNiAl-type structure was investigated by means of powder neutron diffraction. PrPdAl orders below T{sub N} {approx_equal}4.2 K with an incommensurate antiferromagnetic propagation vector k = [1/2,0,{tau}], {tau}=0.398. The best fit was obtained with a sinusoidal modulation of the magnetic moments along the c-axis. (author) 2 figs., 2 refs.

  17. Deletion of Pr130 Interrupts Cardiac Development in Zebrafish

    Directory of Open Access Journals (Sweden)

    Jie Yang

    2016-11-01

    Full Text Available Protein phosphatase 2 regulatory subunit B, alpha (PPP2R3A, a regulatory subunit of protein phosphatase 2A (PP2A, is a major serine/threonine phosphatase that regulates crucial function in development and growth. Previous research has implied that PPP2R3A was involved in heart failure, and PR130, the largest transcription of PPP2R3A, functioning in the calcium release of sarcoplasmic reticulum (SR, plays an important role in the excitation-contraction (EC coupling. To obtain a better understanding of PR130 functions in myocardium and cardiac development, two pr130-deletion zebrafish lines were generated using clustered regularly interspaced short palindromic repeats (CRISPR/CRISPR-associated proteins (Cas system. Pr130-knockout zebrafish exhibited cardiac looping defects and decreased cardiac function (decreased fractional area and fractional shortening. Hematoxylin and eosin (H&E staining demonstrated reduced cardiomyocytes. Subsequent transmission electron microscopy revealed that the bright and dark bands were narrowed and blurred, the Z- and M-lines were fogged, and the gaps between longitudinal myocardial fibers were increased. Additionally, increased apoptosis was observed in cardiomyocyte in pr130-knockout zebrafish compared to wild-type (WT. Taken together, our results suggest that pr130 is required for normal myocardium formation and efficient cardiac contractile function.

  18. Study on GIF PR/PP evaluation methodology

    Energy Technology Data Exchange (ETDEWEB)

    Lee, B. H.; Kwon, E. H.; Kim, H. D. [KAERI, Daejeon (Korea, Republic of)

    2012-10-15

    Proliferation resistance (PR) and physical protection (PP) is one of the four technology goals of generation IV nuclear energy systems (NESs). The PR component of the goal focuses on providing strong assurance that generation IV NESs are the least desirable sources for the diversion or undeclared production of nuclear materials, whereas the PP portion of the goal ensures that generation IV NESs are robust against theft and sabotage. In 2002, the road map of the Generation IV International Forum (GIF) envisioned that the R and D program for PR and PP would have three areas: 1) safeguards and physical protection technology R and D for each GIF system; 2) formulation of PR and PP criteria and metrics; and 3) evaluation of the criteria and metrics. To cover these R and D items, the PR and PP Working Group (PRPPWG) was formed in late 2002 and has since developed a methodology for PR and PP evaluation. In a succession of revisions beginning in 2004, consensus was achieved amongst all participating GIF countries and related organizations (i.e., IAEA and EU), and Revision 6 of the methodology report was approved by GIF for open distribution in 2011. The paper describes in detail the methodology developed by the PRPPWG and discusses its applicability to the sodium-cooled fast reactor (SFR) fuel cycle with pyro processing currently under development in Korea.

  19. O sentido objetivo da prática administrativa

    Directory of Open Access Journals (Sweden)

    Paulo Tromboni Nascimento

    Full Text Available Este artigo examina o sentido da prática administrativa e defende a tese de que é objetivo. A discussão busca a caracterização geral do objeto de investigação. No lugar do objeto das ciências da natureza, inanimado e isolado do sujeito, entra a prática administrativa com sentido objetivo derivado da lógica da situação objetiva do administrador no contexto organizacional. Vale dizer derivado dos propósitos, da rede estruturada de relações sociais e do sistema de práticas da organização. O que torna real a sua axiologia referenciada na eficiência e eficácia da ação, além de fazer da prática administrativa um fator de regulação e mudança controlada da organização. Examinar cientificamente uma prática é criar as condições para mudá-la via uma dialética da descrição, explicação e prescrição. A filosofia da prática é proposta como pressuposto geral da pesquisa científica em administração.

  20. Mechanically alloyed PrFeB nanocrystalline magnets

    International Nuclear Information System (INIS)

    Kaszuwara, W.; Leonowicz, M.

    1998-01-01

    Mechanically alloyed PrFeB nanocrystalline magnets were prepared by extensive ball milling of Pr, Fe and Fe 80 B 20 powders, followed by diffusion annealing. After milling, the material consisted of nanocrystalline α-Fe crystallites embedded in amorphous Pr-rich matrix. Thermomagnetic and calorimetric investigations of the transformations which occurred during annealing showed that the amorphous phase crystallised at 240 C, leading to the formation of crystalline Pr having lattice constants 10% greater than those shown in the ASTM data. This fact indicated that mechanical alloying and low temperature annealing led to the formation of a solid solution of either Fe or B in Pr, which does not exist in the equilibrium state. The Pr 2 Fe 14 B phase was subsequently formed within a temperature range of 420-620 C. The magnetic properties of magnets depend on the phase structure and grain size. Milling time appears to be a decisive processing parameter for the tailoring of the magnetic properties. Depending on the phase structure, the coercivities varied from 100 to 1200 kA/m and, respectively, the remanences from 0.98 T to 0.6 T. The highest maximum energy product was 80 kJ/m 3 . (orig.)

  1. Terapia Familiar y Adicciones. Un enfoque práctico con resultados prácticos

    Directory of Open Access Journals (Sweden)

    Miguel Alberto Ramírez Villaseñor

    2001-01-01

    Full Text Available En el presente trabajo, se describe el fenómeno dela adicción cómo un problema familiar. No sólo por cómo la familia es afectada, sino por la manera en que ésta participa, no en la génesis de la misma sino en el mantenimiento de las conductas consideradas como parte de la enfermedad. Por lo mismo, se describen características que la familia presenta descritas en la literatura especializada de terapia familiar (Stanton y Todds, 1988 y que han sido corroboradas en la práctica clínica qué contradicen muchas de las ideas populares sobre familias de adictos tales cómo: desintegración familiar, descuido familiar, deseos de llamar la atención, madres que trabajan y otros. Las características mencionadas en la literatura son: Dependencia química multigeneracional (generalmente alcohol. Propensión al juego y a mirar T.V. Conspicuamente no esquizofrénica. Fuertes relaciones externas como refugio generalmente después de un conflicto. Ilusión de independencia mayor gracias a la subcultura de la droga. Expresión del conflicto mas primitivo. Alianzas entre miembros y subsistemas explícitas. Prácticas de crianza y necesidades “simbióticas”. Predominio de temas relacionados con la muerte y muertes prematuras, inesperadas y repentinas dentro de la familia. Y disparidad cultural padres-hijos.

  2. Home-based pre-exposure prophylaxis (PrEP services for gay and bisexual men: An opportunity to address barriers to PrEP uptake and persistence.

    Directory of Open Access Journals (Sweden)

    Steven A John

    Full Text Available Gay, bisexual, and other men who have sex with men (GBM are disproportionately affected by the HIV epidemic. Despite the promise of pre-exposure prophylaxis (PrEP in reducing HIV transmission risk, barriers for uptake and persistence exist. We sought to identify whether GBM in a nationwide cohort who have not yet initiated PrEP (n = 906 would prefer to get PrEP-related care from a primary care provider (PCP compared to a specialist clinic or provider. We then sought to identify their level of interest and factors associated with preference for using home-based PrEP services (i.e., HB-PrEP, defined to participants as conducting HIV/STI self-testing from home with PrEP prescription mailing after an initial in-person clinic visit. We examined the associations of demographics, sexual HIV transmission risk, concern about frequent medical checkups associated with PrEP, health care access, and PrEP intentions with preferences for healthcare provider type and HB-PrEP. Concern about frequent medical checkups were associated with preferring a PCP for PrEP-related care, but men who perceived a barrier to bringing up the topic of PrEP with a doctor preferred a specialist clinic or provider more than a PCP. HB-PrEP was more appealing for younger men and those engaged in sexual HIV transmission risk, suggesting HB-PrEP could help reach GBM most vulnerable to HIV and in need of PrEP. HB-PrEP expansion has potential to increase PrEP uptake and persistence among GBM, particularly for men with barriers to clinic-based care and higher intentions to initiate PrEP. Clinical guidelines regarding HB-PrEP are needed to expand its use.

  3. Bulletin of Materials Science | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    Permanent link: https://www.ias.ac.in/article/fulltext/boms/039/03/0603-0611. Keywords. Predominance area diagram; Kellogg diagram; lanthanide oxychloride; rare-earth mineral processing; thermodynamic properties. Abstract. Isothermal stability field diagrams for Ln−O−Cl systems (Ln = La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, ...

  4. Identification of PrP sequences essential for the interaction between the PrP polymers and Aβ peptide in a yeast-based assay

    OpenAIRE

    Rubel, Aleksandr A; Ryzhova, Tatyana A; Antonets, Kirill S; Chernoff, Yury O; Galkin, Alexey P

    2013-01-01

    Alzheimer disease is associated with the accumulation of oligomeric amyloid β peptide (Aβ), accompanied by synaptic dysfunction and neuronal death. Polymeric form of prion protein (PrP), PrPSc, is implicated in transmissible spongiform encephalopathies (TSEs). Recently, it was shown that the monomeric cellular form of PrP (PrPC), located on the neuron surface, binds Aβ oligomers (and possibly other β-rich conformers) via the PrP23–27 and PrP90–110 segments, acting as Aβ receptor. On the other...

  5. Rats and mice immunised with chimeric human/mouse proteinase 3 produce autoantibodies to mouse Pr3 and rat granulocytes

    NARCIS (Netherlands)

    van der Geld, Ymke M.; Hellmark, Thomas; Selga, Daina; Heeringa, Peter; Huitema, Minke G.; Limburg, Pieter C.; Kallenberg, Cees G. M.

    2007-01-01

    Aim: In this study, we employed chimeric human/ mouse Proteinase 3 ( PR3) proteins as tools to induce an autoantibody response to PR3 in rats and mice. Method: Rats and mice were immunised with recombinant human PR3 ( HPR3), recombinant murine PR3 ( mPR3), single chimeric human/ mouse PR3 ( HHm,

  6. 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.

  7. Novel receptor-like kinases in cacao contain PR-1 extracellular domains.

    Science.gov (United States)

    Teixeira, Paulo José Pereira Lima; Costa, Gustavo Gilson Lacerda; Fiorin, Gabriel Lorencini; Pereira, Gonçalo Amarante Guimarães; Mondego, Jorge Maurício Costa

    2013-08-01

    Members of the pathogenesis-related protein 1 (PR-1) family are well-known markers of plant defence responses, forming part of the arsenal of the secreted proteins produced on pathogen recognition. Here, we report the identification of two cacao (Theobroma cacao L.) PR-1s that are fused to transmembrane regions and serine/threonine kinase domains, in a manner characteristic of receptor-like kinases (RLKs). These proteins (TcPR-1f and TcPR-1g) were named PR-1 receptor kinases (PR-1RKs). Phylogenetic analysis of RLKs and PR-1 proteins from cacao indicated that PR-1RKs originated from a fusion between sequences encoding PR-1 and the kinase domain of a LecRLK (Lectin Receptor-Like Kinase). Retrotransposition marks surround TcPR-1f, suggesting that retrotransposition was involved in the origin of PR-1RKs. Genes with a similar domain architecture to cacao PR-1RKs were found in rice (Oryza sativa), barrel medic (Medicago truncatula) and a nonphototrophic bacterium (Herpetosiphon aurantiacus). However, their kinase domains differed from those found in LecRLKs, indicating the occurrence of convergent evolution. TcPR-1g expression was up-regulated in the biotrophic stage of witches' broom disease, suggesting a role for PR-1RKs during cacao defence responses. We hypothesize that PR-1RKs transduce a defence signal by interacting with a PR-1 ligand. © 2013 BSPP AND JOHN WILEY & SONS LTD.

  8. Understanding the Press Kit and Its Use by the Media: When PR Material Becomes News

    Science.gov (United States)

    Weisgerber, Corinne

    2006-01-01

    This activity helps students understand the relationship between public relations (PR) writing and news writing by demonstrating how PR material gets used in the production of news stories. Considering that "more than 70 percent of daily newspaper copy emanates from PR-generated releases," it is important for students to learn how PR professionals…

  9. Features of the advertising and PR in tourism

    Directory of Open Access Journals (Sweden)

    M. A. Zubarieva

    2015-05-01

    Full Text Available The article discusses the use of topical issues of important tools of social communication of applied tactical direction (advertising and strategic (PR. The main types of advertising in tourism and types of PR ­ activities are characterized.The main difference between advertising and PR in the tourism sector is defined, the main attention is given to correct choice of optimal (most efficient advertising channel (means. Specific nature, advertising issues as the main tool for the promotion of tourist product on the network market are defined. The advantages and importance of the innovation of the media as the Internet are detailed. the most popular types of Internet advertising in the tourism sector, in particular ­ placing information in catalogs of Internet resources; registration site in search engines work; banners; mailings via email are considered. The rating position of tourist sites on the Internet (top 15 is shown. A number of approaches to the study and systematization of information of Internet advertising in tourism, the specificity and modern advanced technologies of Internet advertising in the tourism sector are identified. The conclusion about the fact that considered issues about advertising and PR in tourism only form an idea of the complexity and diversity of tourism as advertising via newspapers, radio, television and especially of Internet means. The possibilities of tourism advertising and PR on the Internet have no limits.

  10. Fatores de risco para pré-eclâmpsia

    OpenAIRE

    Moura da Silva, Genivaldo

    2009-01-01

    A pré-eclâmpsia é uma doença específica da gravidez, de etiologia multifatorial, que acomete 5 a 10% das gestantes, cujos efeitos e complicações são a maior causa de morbimortalidade materno-infantil. A identificação de fatores de riscos é importante para a compreensão da patogênese, estabelecimento de estratégias de prevenção e controle da préeclâmpsia. Recentemente estudos clínicos e laboratoriais apontam para a hipótese de associação entre a periodontite materna e pré-eclâmp...

  11. Nomes próprios em Paulo Leminski

    Directory of Open Access Journals (Sweden)

    Olga Kempinska

    2011-06-01

    Full Text Available Este artigo propõe uma discussão sobre o uso dos nomes próprios na obra de Paulo Leminski. Com especial atenção debruça- se sobre a relação entre o nome próprio e o processo social de identificação e de classificação e sobre o potencial subversivo do humor associado ao uso poético do nome próprio por Leminski. Em conclusão insiste-se na ambiguidade envolvida na recepção do humor, subversivo e, ao mesmo tempo, comprometido devido a seu apelo à empatia do leitor.

  12. Fracasos en prótesis parcial removible

    OpenAIRE

    Samsó Manzanedo, Jorge; Salsench Cabré, Juan

    1986-01-01

    Escribir sobre fracasos en prótesis parcial removible entraña ciertas dificultades, entre ellas el especificar qué es un fracaso, qué es un error y lo más difícil, qué es el éxito. Los que esto escriben han visto prótesis parciales removibles ver­daderamente mal realizadas, que han causado un gran daño en el sis­tema estomatognático del portador sin que él se diera cuenta y lo que aún es peor, creyendo que su prótesis satisfacía plenamente los requeri­mientos para poderla considerar un éxito....

  13. 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.)

  14. Jurnalistikadan gələn PR-çı

    OpenAIRE

    Mənsimi, Cəfər; Soltan, Arzu (editör)

    2017-01-01

    Azerbaycan'da ilk online PR derggisi olan PRoloq.az'da PR uzmanı ve "PR labarotoriya"nın başkanı Afet Yaqubova ile röportaj. PR mütəxəssisi və PR laboratoriyanın direktoru Afət Yaqubova ilə müsahibə,

  15. O planejamento como prática do poder

    Directory of Open Access Journals (Sweden)

    Lucas Maia dos Santos

    2009-12-01

    Full Text Available

    Este texto visa apresentar uma leitura crítica acerca da prática de planejamento. Não é um esboço histórico, mas tão-somente uma interpretação do planejamento e como este está inserido na lógica de reprodução da sociedade capitalista. Argumenta para tanto que a prática de planejamento é realizada pela instituição estatal. Esta é um produto genuíno das sociedades de classes. O próprio estado tem como base social uma classe específica: a burocracia. Esta defende, dentro dos quadros da sociedade capitalista, os interesses gerais da burguesia, por mais que possa dentro de dadas circunstâncias sociais específicas opor-se a frações da burguesia, mas nunca aos interesses gerais de classe da burguesia. Defendemos que o poder é uma relação de dominação. Como tal, o planejamento é desta maneira uma manifestação da dominação de classe através da regulação do estado. A instituição estatal é desta forma responsável tanto por regularizar a prática do planejamento, quanto em muitos casos executar os planos ela própria. Assim, defende-se neste texto a necessidade de se superar as relações sociais que engendram o planejamento viabilizado pelo estado. Suprime-se assim o próprio planejamento.

  16. 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.

  17. Atividade antibacteriana in vitro da própolis marrom

    Directory of Open Access Journals (Sweden)

    Maria F.F. Gomes

    2016-04-01

    Full Text Available Resumo Objetivou-se avaliar a atividade antibacteriana in vitro da própolis marrom, por meio da determinação da Concentração Inibitória Mínima (CIM. O extrato alcoólico de própolis foi obtido de 35 g de própolis bruta macerada em 65 mL de álcool de cereais. As concentrações do extrato de própolis usadas foram: 75mg/mL; 56,4mg/mL; 37,5mg/mL; 18,9mg/mL; 9,3mg/mL; 4,5mg/mL e 2,25mg/mL. Foram utilizados 32 isolados de bactérias Gram-positivas: Rhodococcus equi, Staphylococcus aureus, Staphylococcus hyicus, Staphylococcus spp. e Streptococcus spp., e 32 isolados de bactérias Gram-negativas: Enterobacter agglomerans, Escherichia coli, Klebsiella pneumoniae, Klebsiella sp., Pseudomonas aeruginosa, Pseudomonas spp., Salmonella spp. e Serratia rubidaea, provenientes de processos clínicos infecciosos de animais domésticos, obtidas e armazenadas no Laboratório de Bacteriologia da FAMEZ/UFMS. O extrato de própolis marrom apresentou atividade antimicrobiana com CIM variando de 2,25 a 18,9mg/mL para as bactérias Gram-positivas e 4,5 a 18,9mg/mL para as bactérias Gram-negativas, sendo as bactérias provenientes de bovinos e caninos as mais resistentes. Conclui-se que a própolis marrom tem ação bactericida, em função da espécie da bactéria e da procedência animal.

  18. Assistência pré-natal no Brasil

    Directory of Open Access Journals (Sweden)

    Elaine Fernandes Viellas

    2014-08-01

    Full Text Available O estudo tem por objetivo analisar a assistência pré-natal oferecida às gestantes usuárias de serviços de saúde públicos e/ou privados utilizando dados da pesquisa Nascer no Brasil, realizada em 2011 e 2012. As informações foram obtidas por meio de entrevista com a puérpera durante a internação hospitalar e dados do cartão de pré- natal. Os resultados mostram cobertura elevada da assistência pré-natal (98,7% tendo 75,8% das mulheres iniciado o pré-natal antes da 16a semana gestacional e 73,1% compareceram a seis ou mais consultas. O pré-natal foi realizado, sobretudo, em unidades básicas (89,6%, públicas (74,6%, pelo mesmo profissional (88,4%, em sua maioria médicos (75,6%, e 96% receberam o cartão de pré-natal. Um quarto das gestantes foi considerado de risco. Do total das entrevistadas, apenas 58,7% foram orientadas sobre a maternidade de referência, e 16,2% procuraram mais de um serviço para a admissão para o parto. Desafios persistem para a melhoria da qualidade dessa assistência, com a realização de procedimentos efetivos para a redução de desfechos desfavoráveis.

  19. PrEP in Europe - expectations, opportunities and barriers.

    Science.gov (United States)

    McCormack, Sheena Mary; Noseda, Veronica; Molina, Jean-Michel

    2016-01-01

    In contrast to the global trend showing a decline in new HIV infections, the number reported in the World Health Organization (WHO) region of Europe is increasing. Health systems are disparate, but even countries with free access to screening and treatment observe continuing high rates of new infections in key populations, notably men who have sex with men (MSM). Pre-exposure prophylaxis (PrEP) is only available in France. This commentary describes the European epidemics and healthcare settings where PrEP could be delivered, how need might be estimated for MSM and the residual barriers to access. Health systems and government commitment to HIV prevention and care, both financial and political, differ considerably between the countries that make up Europe. A common feature is that funds for prevention are a small fraction of funds for care. Although care is generally good, access is limited in the middle-income countries of Eastern Europe and central Asia, and only 19% of people living with HIV received antiretroviral therapy in 2014. It is challenging to motivate governments or civil society to implement PrEP in the context of this unmet treatment need, which is driven by limited national health budgets and diminishing assistance from foreign aid. The high-income countries of Western Europe have hesitated to embrace PrEP for different reasons, initially due to key gaps in the evidence. Now that PrEP has been shown to be highly effective in European MSM in two randomized controlled trials, it is clear that the major barrier is the cost of the drug which is still on patent, although inadequate health systems and diminishing investment in civil society are also key challenges to overcome. The momentum to implement PrEP in European countries is increasing and provides a welcome opportunity to expand and improve clinical services and civil society support focused on HIV and related infections including other sexually transmitted and blood-borne infections.

  20. 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...

  1. Microwave absorption in YBCO/PrBCO superlattices

    International Nuclear Information System (INIS)

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

    1992-01-01

    In this paper, non-resonant microwave absorption is employed to probe YBCO/PrBCO superlattices and compare the response to that of a YBCO film. Near the transition temperatures, the response of the superlattice samples and the YBCO film have similar amplitudes and orientation dependencies. 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 dependencies, which the authors attribute to the role of the PrBCO layers

  2. French post office on the Prévessin Site

    CERN Multimedia

    DG Unit

    2009-01-01

    At CERN’s request, the French postal service has reviewed the opening hours that have been in effect since 4 May of this year. As from 20 July, the new public opening hours for the post office on the Prévessin site will be 9:30 a.m. to 1:00 p.m., Monday to Friday. The opening hours will be reviewed again in the autumn. For further information, please contact the Prévessin site post office on 77071. Relations with the Host States Service Tel.: 72848 mailto:relations.secretariat@cern.ch

  3. Competing phases in a model of Pr-based cobaltites

    Science.gov (United States)

    Sotnikov, A.; Kuneš, J.

    2017-12-01

    Motivated by the physics of Pr-based cobaltites, we study the effect of the external magnetic field in the hole-doped two-band Hubbard model close to instabilities toward the excitonic condensation and ferromagnetic ordering. Using the dynamical mean-field theory we observe a field-driven suppression of the excitonic condensate. The onset of a magnetically ordered phase at the fixed chemical potential is accompanied by a sizable change of the electron density. This leads us to predict that Pr3 + abundance increases on the high-field side of the transition.

  4. Kunstisuvi 1999 / Sirje Eelma, Rait Prääts

    Index Scriptorium Estoniae

    Eelma, Sirje, 1950-

    1999-01-01

    12. juunist näitus "Rahvusvaheline väikegraafika ja eesti väikeskulptuur" Kuressaare Raegaleriis. Koostajad ja kujundajad Sirje Eelma, Terje Ojaver. 19. juunist Haapsalu Linnagaleriis ja lisaruumides väljapanek "Motiiv". Koostajad Agur Kruusing, Sirje Eelma, Rait Prääts, kujundaja Agur Kruusing. Pärnu Linnagaleriis näitus "Minimaal". Koostaja ja kujundaja Rait Prääts. Muuseumiaidas eesti noorema kunsti väljapanek "Voolab". Koostaja Karol Kallas. Juuli lõpul Selgase dolomiidipäevad Kuressaares. Pärast põhinäituste lõppemist valiknäitus Paide Vallitornis

  5. Farmakologisk behandling af præmatur ejakulation

    DEFF Research Database (Denmark)

    Kuhlmann, Ida Berglund; Hedegaard, Ulla; Christensen, Mette Marie H

    2017-01-01

    Forfatterne anbefaler lokalanæstesi med lidokain og/eller prilokain som førstevalg. Andet valg til behandling vil være dapoxetin, som er en korttidsvirkende SSRI med indikationen præmatur ejakulation. Som tredje valg kan overvejes SSRI'et sertralin......Forfatterne anbefaler lokalanæstesi med lidokain og/eller prilokain som førstevalg. Andet valg til behandling vil være dapoxetin, som er en korttidsvirkende SSRI med indikationen præmatur ejakulation. Som tredje valg kan overvejes SSRI'et sertralin...

  6. Determination of the magnetic moment of $^{140}$Pr

    CERN Multimedia

    Kowalska, M; Kreim, K D; Krieger, A R; Litvinov, Y

    We propose to measure the nuclear magnetic moment of the neutron-deficient isotope $^{140}$Pr using collinear laser spectroscopy at the COLLAPS experiment. This nuclide is one of two nuclear systems for which a modulated electron capture decay has been observed in hydrogen-like ions in a storage ring. The firm explanation of the observed phenomenon is still missing but some hypotheses suggest an interaction of the unpaired electron with the surrounding magnetic fields of the ring. In order to verify or discard these hypotheses the magnetic moment of $^{140}$Pr is required since this determines the energy of the 1s hyperfine splitting.

  7. Best Practices marketing relacional. Caso práctico

    OpenAIRE

    Cardama Otero, Maria

    2016-01-01

    el proyecto quiere servir de guía de buenas prácticas para el marketing digital de un comercio. Se desarrolla un caso práctico referido a una tienda de ropa infantil. This Project studies how a firm should develop a digital marketing strategy. We aim to propose ways to establish collaborative relationships to deliver value to customers and stakeholders, and see how they should be integrated in the overall value proposition. A general framework of best practices is described and applied to ...

  8. Role of cell death in the propagation of PrP(Sc) in immune cells.

    Science.gov (United States)

    Takahashi, Kenichi; Inoshima, Yasuo; Ishiguro, Naotaka

    2015-03-01

    A number of studies have suggested that macrophages, dendritic cells, and follicular dendritic cells play an important role in the propagation of PrP(Sc). Both accumulation and proteolysis of PrP(Sc) have been demonstrated in peripheral macrophages. Macrophages may act as reservoirs for PrP(Sc) particles if the cells die during transient PrP(Sc) propagation. However, whether cell death plays a role in PrP(Sc) propagation in macrophages remains unclear. In this study, we investigated the possibility of propagation and transmission of PrP(Sc) between dead immune cells and living neural cells. We found that under specific conditions, transient PrP(Sc) propagation occurs in dead cells, indicating that interaction between PrP(C) and PrP(Sc) on plasma membrane lipid rafts might be important for PrP(Sc) propagation. Co-culturing of killed donor PrP(Sc)-infected macrophages with recipient N2a-3 neuroblastoma cells accelerated PrP(Sc) transmission. Our results suggest that cell death may play an important role in PrP(Sc) propagation, whereas transient PrP(Sc) propagation in macrophages has little effect on PrP(Sc) transmission.

  9. Prática de ensino supervisionada em educação pré-escolar

    OpenAIRE

    Patrício, Linda Cristel

    2017-01-01

    O presente relatório de estágio desenvolveu-se no âmbito da Prática de Ensino Supervisionada, tendo por finalidade a obtenção do grau de mestre em Educação Pré-Escolar. A prática educativa foi desenvolvida em contexto de Creche e Jardim-de-Infância e a temática que me mereceu particular reflexão foi o desenvolvimento motor, no sentido de saber que oportunidades neste âmbito, são proporcionadas às crianças. Considerando a educação física como um domínio enquadrado nas Orientações Curricular...

  10. Sialic Acid on the Glycosylphosphatidylinositol Anchor Regulates PrP-mediated Cell Signaling and Prion Formation.

    Science.gov (United States)

    Bate, Clive; Nolan, William; Williams, Alun

    2016-01-01

    The prion diseases occur following the conversion of the cellular prion protein (PrP(C)) into disease-related isoforms (PrP(Sc)). In this study, the role of the glycosylphosphatidylinositol (GPI) anchor attached to PrP(C) in prion formation was examined using a cell painting technique. PrP(Sc) formation in two prion-infected neuronal cell lines (ScGT1 and ScN2a cells) and in scrapie-infected primary cortical neurons was increased following the introduction of PrP(C). In contrast, PrP(C) containing a GPI anchor from which the sialic acid had been removed (desialylated PrP(C)) was not converted to PrP(Sc). Furthermore, the presence of desialylated PrP(C) inhibited the production of PrP(Sc) within prion-infected cortical neurons and ScGT1 and ScN2a cells. The membrane rafts surrounding desialylated PrP(C) contained greater amounts of sialylated gangliosides and cholesterol than membrane rafts surrounding PrP(C). Desialylated PrP(C) was less sensitive to cholesterol depletion than PrP(C) and was not released from cells by treatment with glimepiride. The presence of desialylated PrP(C) in neurons caused the dissociation of cytoplasmic phospholipase A2 from PrP-containing membrane rafts and reduced the activation of cytoplasmic phospholipase A2. These findings show that the sialic acid moiety of the GPI attached to PrP(C) modifies local membrane microenvironments that are important in PrP-mediated cell signaling and PrP(Sc) formation. These results suggest that pharmacological modification of GPI glycosylation might constitute a novel therapeutic approach to prion diseases. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  11. 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.

  12. Comunidades virtuales de práctica y aprendizaje

    OpenAIRE

    Rodríguez Illera, José Luis

    2007-01-01

    Las comunidades virtuales, sean de práctica o de aprendizaje según una distinción habitual, han adquirido un lugar central en la sociedad actual, especialmente por los avancestecnológicos y la denominada web social.

  13. PR aitab tulemusi saavutada piirangute kiuste / Jekaterina Eilart

    Index Scriptorium Estoniae

    Eilart, Jekaterina

    2014-01-01

    Olympic Entertainment Group laiendas 2013. aasta suvel oma online-äri ning sisenes "OlyBet" kaubamärgi all spordiennustuse turule. Suhtekorralduse Auhind 2013 erasektori kategooria võitnud projektist "PR-toetus OlyBeti kaubamärgi lansseerimisele" - kaubamärgi tutvustamiseks korraldatud kommunikatsioonist ja meediasuhete loomise projektist

  14. 78 FR 3495 - Puerto Rico Disaster #PR-00017

    Science.gov (United States)

    2013-01-16

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 13437 and 13438] Puerto Rico Disaster PR-00017 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY: This is a notice of an Administrative declaration of a disaster for the Commonwealth of Puerto Rico Dated 01/03/2013. Incident: Heavy...

  15. PR IN HIGH-TEMPERATURE SUPERCONDUCTORS - INSULATING PLANES, METALLIC CHAINS

    NARCIS (Netherlands)

    KHOMSKII, D

    Critical discussion is given of the properties of Pr-containing high-T(c) superconductors, especially Y1-xPrxBa2Cu3O7. It is argued that the models proposed to explain suppression of T(c) and other properties of this system (pairbreaking; hole filling; strong p-f hybridization) are inadequate and

  16. 76 FR 47286 - Puerto Rico Disaster Number PR-00013

    Science.gov (United States)

    2011-08-04

    ... SMALL BUSINESS ADMINISTRATION Disaster Declaration 12699 and 12700 Puerto Rico Disaster Number PR-00013 AGENCY: U.S. Small Business Administration. ACTION: Amendment 1. SUMMARY: This is an amendment of the Presidential declaration of a major disaster for Public Assistance Only for the State of Puerto...

  17. 75 FR 39060 - Puerto Rico Disaster #PR-00009

    Science.gov (United States)

    2010-07-07

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12214 and 12215] Puerto Rico Disaster PR-00009 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY: This is a Notice of the Presidential declaration of a major disaster for Public Assistance Only for the Commonwealth of Puerto Rico (FEMA-1919-DR...

  18. 76 FR 55155 - Puerto Rico Disaster #PR-00014

    Science.gov (United States)

    2011-09-06

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12768 and 12769] Puerto Rico Disaster PR-00014 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY: This is a Notice of the Presidential declaration of a major disaster for the Commonwealth of Puerto Rico (FEMA-4017-DR), dated 08/ 27/2011...

  19. 76 FR 67244 - Puerto Rico Disaster Number PR-00014

    Science.gov (United States)

    2011-10-31

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12768 and 12769] Puerto Rico Disaster Number PR-00014 AGENCY: U.S. Small Business Administration. ACTION: Amendment 5. SUMMARY: This is an amendment of the Presidential declaration of a major disaster for the Commonwealth of Puerto Rico (FEMA-4017...

  20. 75 FR 51294 - Puerto Rico Disaster # PR-00010

    Science.gov (United States)

    2010-08-19

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12270 and 12271] Puerto Rico Disaster PR-00010 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY: This is a notice of an Administrative declaration of a disaster for the Commonwealth of PUERTO RICO dated 08/11/2010. Incident: Severe...

  1. 76 FR 59179 - Puerto Rico Disaster Number PR-00014

    Science.gov (United States)

    2011-09-23

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12768 and 12769] Puerto Rico Disaster Number PR-00014 AGENCY: U.S. Small Business Administration. ACTION: Amendment 2. SUMMARY: This is an amendment of the Presidential declaration of a major disaster for the Commonwealth of Puerto Rico (FEMA-4017...

  2. 76 FR 59178 - Puerto Rico Disaster Number PR-00015

    Science.gov (United States)

    2011-09-23

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12770 and 12771] Puerto Rico Disaster Number PR-00015 AGENCY: U.S. Small Business Administration. ACTION: Amendment 2. SUMMARY: This is an amendment of the Presidential declaration of a major disaster for Public Assistance Only for the...

  3. 76 FR 63699 - Puerto Rico Disaster Number PR-00015

    Science.gov (United States)

    2011-10-13

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12770 and 12771] Puerto Rico Disaster Number PR-00015 AGENCY: U.S. Small Business Administration. ACTION: Amendment 4. SUMMARY: This is an amendment of the Presidential declaration of a major disaster for Public Assistance Only for the...

  4. 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

  5. 75 FR 69733 - Puerto Rico Disaster #PR-00012

    Science.gov (United States)

    2010-11-15

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12368 and 12369] Puerto Rico Disaster PR-00012 AGENCY: U.S. Small Business Administration. ACTION: Amendment 1. SUMMARY: This is an amendment of the Presidential declaration of a major disaster for Public Assistance Only for the Commonwealth of Puerto Rico...

  6. Simple explanation for the reentrant magnetic phase transition in Pr ...

    Indian Academy of Sciences (India)

    The reentrant magnetic phase transition in Pr0.5Sr0.41Ca0.09MnO3 perovskite is explained using the Ising spin model on the square lattice with mixed ferromagnetic and antiferromagnetic exchange interactions. It is shown using numerical calculations that this effect is strongly affected by the external magnetic field and ...

  7. 75 FR 68394 - Puerto Rico Disaster # PR-00012

    Science.gov (United States)

    2010-11-05

    ... SMALL BUSINESS ADMINISTRATION Disaster Declaration 12368 and 12369 Puerto Rico Disaster PR-00012 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY: This is a Notice of the Presidential declaration of a major disaster for Public Assistance Only for the Commonwealth of Puerto Rico (FEMA--1946--DR...

  8. 78 FR 4966 - Puerto Rico Disaster #PR-00018

    Science.gov (United States)

    2013-01-23

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 13445 and 13446] Puerto Rico Disaster PR-00018 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY: This is a notice of an Administrative declaration of a disaster for the Commonwealth of Puerto Rico dated 01/10/2013. Incident: Tropical...

  9. 76 FR 55154 - Puerto Rico Disaster #PR-00015

    Science.gov (United States)

    2011-09-06

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12770 and 12771] Puerto Rico Disaster PR-00015 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY: This is a Notice of the Presidential declaration of a major disaster for Public Assistance Only for the Commonwealth of Puerto Rico (FEMA-4017-DR...

  10. 75 FR 76517 - Puerto Rico Disaster Number PR-00012

    Science.gov (United States)

    2010-12-08

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12368 and 12369] Puerto Rico Disaster Number PR-00012 AGENCY: U.S. Small Business Administration. ACTION: Amendment 2. SUMMARY: This is an amendment of the Presidential declaration of a major disaster for Public Assistance Only for the...

  11. ions (RE = La, Pr, Nd, Sm, Gd and Dy)

    Indian Academy of Sciences (India)

    ) zirconia), tendency of phase transformation (tetragonal to monoclinic () zirconia) and lattice strain were studied with mechanical property e.g. tensile strength of sol–gel derived ZrO2–2 mol% RE2O3 (RE = La, Pr, Nd, Sm, Gd and Dy) spun ...

  12. 76 FR 56858 - Puerto Rico Disaster Number PR-00014

    Science.gov (United States)

    2011-09-14

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12768 and 12769] Puerto Rico Disaster Number PR-00014 AGENCY: U.S. Small Business Administration. ACTION: Amendment 1. SUMMARY: This is an amendment of the Presidential declaration of a major disaster for the Commonwealth of Puerto Rico (FEMA-4017...

  13. 76 FR 44647 - Puerto Rico Disaster #PR-00013

    Science.gov (United States)

    2011-07-26

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12699 and 12700] Puerto Rico Disaster PR-00013 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY: This is a Notice of the Presidential declaration of a major disaster for Public Assistance Only for the Commonwealth of Puerto Rico (FEMA-4004-DR...

  14. 76 FR 66768 - Puerto Rico Disaster #PR-00016

    Science.gov (United States)

    2011-10-27

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12897 and 12898] Puerto Rico Disaster PR-00016 AGENCY: U.S. Small Business Administration. ACTION: Notice. SUMMARY: This is a Notice of the Presidential declaration of a major disaster for the Commonwealth of Puerto Rico (FEMA-4040-DR), dated 10/ 18/2011...

  15. 76 FR 62133 - Puerto Rico Disaster Number PR-00015

    Science.gov (United States)

    2011-10-06

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12770 and 12771] Puerto Rico Disaster Number PR-00015 AGENCY: U.S. Small Business Administration. ACTION: Amendment 3. SUMMARY: This is an amendment of the Presidential declaration of a major disaster for Public Assistance only for the...

  16. 76 FR 56861 - Puerto Rico Disaster Number PR-00015

    Science.gov (United States)

    2011-09-14

    ... SMALL BUSINESS ADMINISTRATION [Disaster Declaration 12770 and 12771] Puerto Rico Disaster Number PR-00015 AGENCY: U.S. Small Business Administration. ACTION: Amendment 1. SUMMARY: This is an amendment of the Presidential declaration of a major disaster for Public Assistance Only for the...

  17. Marketing Your Library Program--More than a PR Campaign.

    Science.gov (United States)

    Brown, Gerald R.

    In this workshop, the concept of marketing was applied to school library media programs by examining the relationship between library media programs, the marketing plan, public relations (PR), and promotion. Reachable goals, targeting the audience, advertising, and motivation and commitment of the staff were also considered, and successful…

  18. Maksuameti ja Paltsi PR-sõda leevenemas / Toomas Mattson

    Index Scriptorium Estoniae

    Mattson, Toomas, 1970-

    2003-01-01

    Maksuameti ajutine juht Aivar Rehe tegi suhtekorraldusfirmale Alfa Omega Communications ettepaneku lõpetada PR-leping. Rahandusminister Tõnis Paltsi nõustamisest. Vt. samas lühiintervjuud Tõnis Paltsiga: Palts: Olin üksi lahinguväljal. Lisad: Tõnis Paltsi ja Maksuameti vägikaikaveo kronoloogia

  19. How European PR practitioners handle digital and social media

    NARCIS (Netherlands)

    Verhoeven, P.; Tench, R.; Zerfass, A.; Moreno, A.; Verčič, D.

    2012-01-01

    The European Communication Monitor (ECM) 2010 showed that digital communication and social media have grown in importance in the media mix of European organizations. Both new media types are positively correlated to the perceived impact of public relations (PR) in the organization. Specifically

  20. Præstationsledelse gentænkt

    DEFF Research Database (Denmark)

    Elmholdt, Claus Westergård; Sørensen, Niels Henrik

    2016-01-01

    smidige styrings- og vurderingssystemer, som er integreret i en dagligdags ledelsespraksis, der nedbryder KPI’er, opstiller meningsfulde mål og giver kontinuerlig, konkret og konstruktiv feedback. Vi diskuterer, med afsæt i tre caseeksempler, faldgruber i en klassisk tilgang til præstationsledelse og...

  1. Triplet superconductivity in PrOs4Sb12

    International Nuclear Information System (INIS)

    Maki, K.; Won, H.; Parker, David; Haas, Stephan; Izawa, K.; Matsuda, Y.

    2005-01-01

    Here we propose spin triplet superconductors for the A- and B-phase in PrOs 4 Sb 12 . The present model describes consistently the thermal conductivity κ zz data obtained by Izawa et al. for T>=150mK

  2. Aprendizagem como/na prática

    Directory of Open Access Journals (Sweden)

    Jean Lave

    2015-12-01

    Full Text Available ResumoEste artigo considera como o estudo da cultura e da aprendizagem pode ser de particular relevância para o campo da antropologia sociocultural em geral. O termo mais importante na expressão “cultura & aprendizagem” talvez seja o logograma “&” – ou seja, coloca-se a questão sobre o que conecta cultura e aprendizagem, perguntando-se como esses termos estão relacionados. Como devemos compreender cultura e aprendizagem como instâncias produtoras delas próprias, e uma da outra, na prática? Recalibrando em termos relacionais, podemos dizer que não é possível abordar a “aprendizagem” ou “cultura e aprendizagem” sem o seu emaranhamento na vida político-econômica, nas lutas e disputas históricas, em suas coerências e incoerências, e na produção relacional e histórica da vida cotidiana. Através das lentes da teoria da prática social, os estudos etnográficos sobre aprendizagem na prática oferecem diferentes entendimentos sobre como certa vida e certas disputas e incoerências são produzidas.

  3. Early Delivery of Misfolded PrP from ER to Lysosomes by Autophagy

    Science.gov (United States)

    Cortes, Constanza J.; Qin, Kefeng; Norstrom, Eric M.; Green, William N.; Bindokas, Vytautas P.; Mastrianni, James A.

    2013-01-01

    Prion diseases are linked to the accumulation of a misfolded isoform (PrPSc) of prion protein (PrP). Evidence suggests that lysosomes are degradation endpoints and sites of the accumulation of PrPSc. We questioned whether lysosomes participate in the early quality control of newly generated misfolded PrP. We found PrP carrying the disease-associated T182A mutation (Mut-PrP) was delivered to lysosomes in a Golgi-independent manner. Time-lapse live cell imaging revealed early formation and uptake of GFP-tagged Mut-PrP aggregates into LysoTracker labeled vesicles. Compared with Wt-PrP, Mut-PrP expression was associated with an elevation in several markers of the autophagy-lysosomal pathway, and it extensively colocalized with the autophagosome-specific marker, LC3B. In autophagy deficient (ATG5−/−) mouse embryonic fibroblasts, or in normal cells treated with the autophagy-inhibitor 3-MA, Mut-PrP colocalization with lysosomes was reduced to a similar extent. Additionally, 3-MA selectively impaired the degradation of insoluble Mut-PrP, resulting in an increase in protease-resistant PrP, whereas the induction of autophagy by rapamycin reduced it. These findings suggest that autophagy might function as a quality control mechanism to limit the accumulation of misfolded PrP that normally leads to the generation of PrPSc. PMID:24454378

  4. Relato de atividades práticas vivenciadas

    Directory of Open Access Journals (Sweden)

    Marlise Rieger

    2011-12-01

    Full Text Available O presente artigo tem por principal objetivo a descrição e análise crítica das atividades práticas vivenciadas no Centro Municipal de Educação Infantil, localizada na cidade de Sinop-MT. O referido estágio Curricular Supervisionado foi realizado durante o sexto semestre do curso de Licenciatura Plena em Pedagogia. O qual é necessário para uma formação profissional a fim de adequar essa formação às expectativas do mercado de trabalho onde o licenciado irá atuar. O estágio de atividades práticas da oportunidade de aliar e fortalecer a teoria com a prática. A metodologia utilizada nas atividades práticas com as crianças foi de socializar e estimular a criatividade e a oralidade. Nas crianças, com a faixa etária de 4 e 5 anos, as mudanças ocorrem muito rápido e se processam aos saltos contínuos de organização, interagindo de diferentes maneiras no ambiente físico e social que o cerca numa instituição, diferente das que vive com suas famílias. O resultado obtido nesse estágio foi de suma importância para a compreensão, que cabe ao professor trabalhar com conteúdos diversos, básicos essenciais ate os conhecimentos específicos das diversas áreas do conhecimento. Palavras-chave: educação infantil; estágio curricular supervisionado; atividades práticas; crianças.

  5. 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

  6. 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.

  7. 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.

  8. Ubiquitin Ligase gp78 Targets Unglycosylated Prion Protein PrP for Ubiquitylation and Degradation

    OpenAIRE

    Shao, Jia; Choe, Vitnary; Cheng, Haili; Tsai, Yien Che; Weissman, Allan M.; Luo, Shiwen; Rao, Hai

    2014-01-01

    Prion protein PrP is a central player in several devastating neurodegenerative disorders, including mad cow disease and Creutzfeltd-Jacob disease. Conformational alteration of PrP into an aggregation-prone infectious form PrPSc can trigger pathogenic events. How levels of PrP are regulated is poorly understood. Human PrP is known to be degraded by the proteasome, but the specific proteolytic pathway responsible for PrP destruction remains elusive. Here, we demonstrate that the ubiquitin ligas...

  9. Review of HIV Pre exposure prophylaxis (PrEP) and example of HIV PrEP Toolkit

    Science.gov (United States)

    2017-08-28

    at Initiation of Sexual Activity Correct & Consistent Condom Use Prevention of mother-to- child transmission July 16, 2012: FDA approves...Okulicz JF, Medicine 2016 PrEP Utilization in a Managed Care System (Kaiser Permanente) 1200 ~ 1045 1000 . 800 600 . 400 200 0 835 657 0

  10. Solid-state phase equilibria in the Fe-Pt-Pr ternary system at 1173 K

    International Nuclear Information System (INIS)

    Ren Jing; Gu Zhengfei; Cheng Gang; Zhou Huaiying

    2005-01-01

    The solid-state phase equilibria in the Fe-Pt-Pr ternary system at 1173 K (Pr ≤ 70%) were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersion spectroscopy (EDS) techniques. The 1173 K isothermal section consists of 13 single-phase regions, 22 two-phase regions and 10 three-phase regions. At 1173 K, we have observed that the maximum solid solubility of Pt in α-Fe is below 1.5 at.% and the solid solution region of Pt in γ-Fe is from 2 to 35 at.%; the maximum solid solubility of Fe in Pt is 18 at.%. The maximum solubility of Fe in PrPt 5 , PrPt 3 , PrPt 2 , Pr 3 Pt 4 , PrPt, Pr 3 Pt 2 and Pr 7 Pt 3 is below 1 at.%. The maximum solubility of Pr in α-(Fe, Pt), γ-(Fe, Pt), FePt, FePt 3 and (Pt, Fe) (the solid solution of Fe in Pt) is 6, 2, 4, 4.5 and 1.5 at.%, respectively. In this work, it is found that the phase Pr 3 Pt 4 does not exist in the ternary system. The binary compounds Fe 7 Pr and Fe 2 Pr and any new ternary compounds were not observed

  11. Nasal associated lymphoid tissue of the Syrian golden hamster expresses high levels of PrPC.

    Directory of Open Access Journals (Sweden)

    Melissa D Clouse

    Full Text Available The key event in the pathogenesis of the transmissible spongiform encephalopathies is a template-dependent misfolding event where an infectious isoform of the prion protein (PrPSc comes into contact with native prion protein (PrPC and changes its conformation to PrPSc. In many extraneurally inoculated models of prion disease this PrPC misfolding event occurs in lymphoid tissues prior to neuroinvasion. The primary objective of this study was to compare levels of total PrPC in hamster lymphoid tissues involved in the early pathogenesis of prion disease. Lymphoid tissues were collected from golden Syrian hamsters and Western blot analysis was performed to quantify PrPC levels. PrPC immunohistochemistry (IHC of paraffin embedded tissue sections was performed to identify PrPC distribution in tissues of the lymphoreticular system. Nasal associated lymphoid tissue contained the highest amount of total PrPC followed by Peyer's patches, mesenteric and submandibular lymph nodes, and spleen. The relative levels of PrPC expression in IHC processed tissue correlated strongly with the Western blot data, with high levels of PrPC corresponding with a higher percentage of PrPC positive B cell follicles. High levels of PrPC in lymphoid tissues closely associated with the nasal cavity could contribute to the relative increased efficiency of the nasal route of entry of prions, compared to other routes of infection.

  12. Nasal associated lymphoid tissue of the Syrian golden hamster expresses high levels of PrPC.

    Science.gov (United States)

    Clouse, Melissa D; Shikiya, Ronald A; Bartz, Jason C; Kincaid, Anthony E

    2015-01-01

    The key event in the pathogenesis of the transmissible spongiform encephalopathies is a template-dependent misfolding event where an infectious isoform of the prion protein (PrPSc) comes into contact with native prion protein (PrPC) and changes its conformation to PrPSc. In many extraneurally inoculated models of prion disease this PrPC misfolding event occurs in lymphoid tissues prior to neuroinvasion. The primary objective of this study was to compare levels of total PrPC in hamster lymphoid tissues involved in the early pathogenesis of prion disease. Lymphoid tissues were collected from golden Syrian hamsters and Western blot analysis was performed to quantify PrPC levels. PrPC immunohistochemistry (IHC) of paraffin embedded tissue sections was performed to identify PrPC distribution in tissues of the lymphoreticular system. Nasal associated lymphoid tissue contained the highest amount of total PrPC followed by Peyer's patches, mesenteric and submandibular lymph nodes, and spleen. The relative levels of PrPC expression in IHC processed tissue correlated strongly with the Western blot data, with high levels of PrPC corresponding with a higher percentage of PrPC positive B cell follicles. High levels of PrPC in lymphoid tissues closely associated with the nasal cavity could contribute to the relative increased efficiency of the nasal route of entry of prions, compared to other routes of infection.

  13. Lessons learned from the experiences of informal PrEP users in France: results from the ANRS-PrEPage study.

    Science.gov (United States)

    Rivierez, I; Quatremere, G; Spire, B; Ghosn, J; Rojas Castro, D

    2018-05-30

    Before January 2016, Pre-Exposure Prophylaxis (PrEP), a new biomedical HIV-prevention tool, was only available in France via ANRS-Ipergay clinical study but informal use was reported outside this setting. PrEPage qualitative study reports profiles and experiences of participants who used PrEP outside of a biomedical trial before this prevention method was authorized. Between March 2015 and February 2016, a cross-section of twenty-four informal PrEP users, mostly MSM, was recruited to complete in-depth semi-structured interviews. While ANRS-Ipergay was still ongoing (2012-2016), participants described their initiation to PrEP, the way they used it and the difficulties they faced to acquire antiretroviral drugs in an environment where PrEP was still not widely known and often criticized . Through the testimonies, different user profiles and motivation toward informal PrEP use emerged: (a) participants who have increasing difficulties using condoms, (b) "opportunists" who tried PrEP without the intention of using it regularly and (c) participants with a risk aversion who sought additional protection against HIV. Participants chose to use PrEP and/or their usual prevention strategies depending on available supplies, type of partners and individual attitudes toward risk. The feeling of living a safer sex life helped participants to outweigh the fear of possible toxicity and drug resistance. Participants' needs and expectations about PrEP implementation in France were also presented.

  14. PrPc Does Not Mediate Internalization of PrPSc but Is Required at an Early Stage for De Novo Prion Infection of Rov Cells▿

    Science.gov (United States)

    Paquet, Sophie; Daude, Nathalie; Courageot, Marie-Pierre; Chapuis, Jérôme; Laude, Hubert; Vilette, Didier

    2007-01-01

    We have studied the interactions of exogenous prions with an epithelial cell line inducibly expressing PrPc protein and permissive to infection by a sheep scrapie agent. We demonstrate that abnormal PrP (PrPSc) and prion infectivity are efficiently internalized in Rov cells, whether or not PrPc is expressed. At odds with earlier studies implicating cellular heparan sulfates in PrPSc internalization, we failed to find any involvement of such molecules in Rov cells, indicating that prions can enter target cells by several routes. We further show that PrPSc taken up in the absence of PrPc was unable to promote efficient prion multiplication once PrPc expression was restored in the cells. This observation argues that interaction of PrPSc with PrPc has to occur early, in a specific subcellular compartment(s), and is consistent with the view that the first prion multiplication events may occur at the cell surface. PMID:17626095

  15. Molecular insights on analogs of HIV PR inhibitors toward HTLV-1 PR through QM/MM interactions and molecular dynamics studies: comparative structure analysis of wild and mutant HTLV-1 PR.

    Science.gov (United States)

    Selvaraj, Chandrabose; Singh, Poonam; Singh, Sanjeev Kumar

    2014-12-01

    Retroviruses HTLV-1 and HIV-1 are the primary causative agents of fatal adult T-cell leukemia and acquired immune deficiency syndrome (AIDS) disease. Both retroviruses are similar in characteristics mechanism, and it encodes for protease that mainly involved in the viral replication process. On the basis of the therapeutic success of HIV-1 PR inhibitors, the protease of HTLV-1 is mainly considered as a potential target for chemotherapy. At the same time, structural similarities in both enzymes that originate HIV PR inhibitors can also be an HTLV-1 PR inhibitor. But the expectations failed because of rejection of HIV PR inhibitors from the HTLV-1 PR binding pocket. In this present study, the reason for the HIV PR inhibitor rejection from the HTLV-1 binding site was identified through sequence analysis and molecular dynamics simulation method. Functional analysis of M37A mutation in HTLV PR clearly shows that the MET37 specificity and screening of potential inhibitors targeting MET37 is performed by using approved 90% similar HIV PR inhibitor compounds. From this approach, we report few compounds with a tendency to accept/donate electron specifically to an important site residue MET37 in HTLV-1 PR binding pocket. Copyright © 2014 John Wiley & Sons, Ltd.

  16. Conditions promoting and restraining agronomic effectiveness of water-insoluble phosphate sources, in particular phosphate rock (PR): III. 32P-aided soil-PR interaction studies aimed at enhancing P bioavailability from PR

    International Nuclear Information System (INIS)

    Borlan, Z.; Soare, M.; Gavriluta, I.; Alexandrescu, A.; Stefanescu, D.

    2002-01-01

    Mobilization of PR and bioavailability of PR-P for plants takes place through complex chemical and biochemical processes that occurs during prolonged soil interaction with PR. There is a high probability that certain processes of a biochemical nature are also involved through proteinaceous ion carriers whose concentration and physiological activity in plant roots may be influenced by means of specially formulated foliar fertilizer compositions. 32 P-aided studies have contributed to identify possibilities of enhancing PR-P bioavailability through foliar fertilizer application. (author)

  17. Demographic differences in PrEP–related stereotypes: Implications for implementation

    Science.gov (United States)

    Golub, Sarit. A.; Gamarel, Kristi E.; Surace, Anthony

    2015-01-01

    Qualitative interviews about pre-exposure prophylaxis (PrEP) stereotypes were conducted with a subsample of 160 MSM who participated in a PrEP messaging study. Negative stereotypes about PrEP users were identified by 80% of participants. Two types of stereotypes were most common: PrEP users are HIV-infected (and lying about it), and PrEP users are promiscuous and resistant to condom use. Participants’ identification of these stereotype categories differed significantly by demographic factors (i.e. race/ethnicity, education). Expanding access to PrEP requires recognizing potential differences in the experience or anticipation of PrEP-related stereotypes that might impact willingness to discuss PrEP with providers, friends, or partners. PMID:26143247

  18. PR-teenuse hind tõuseb 20% / Eda-Liis Kann

    Index Scriptorium Estoniae

    Kann, Eda-Liis, 1979-

    2004-01-01

    Suhtekorraldusfirmad prognoosivad aasta teiseks pooleks PR-teenuste 20protsendilist hinnatõusu. Kommenteerivad Kersti Luha, Maren Pärn, Ingrid Eha, Maria Raudsepp, Heidi Pihlak ja Rein Meripõld. Lisa: Väikefirmale on PR-teenus kallis

  19. Epidemiology of Chronic Wasting Disease: PrPres Detection, Shedding and Environmental Contamination

    National Research Council Canada - National Science Library

    Lewis, Randolph V

    2005-01-01

    .... The specific goals of these studies are to develop sensitive assays for PrP(exp res) as a marker for infectivity, and use these techniques to monitor the dynamics and modes of shedding of PrP(exp res...

  20. Characteristics of PR interval as predictor for atrial fibrillation: association with biomarkers and outcomes.

    Science.gov (United States)

    Schumacher, Katja; Dagres, Nikolaos; Hindricks, Gerhard; Husser, Daniela; Bollmann, Andreas; Kornej, Jelena

    2017-10-01

    The PR interval may be considered as a simple and easily obtainable predictor for adverse events, including atrial fibrillation (AF), pacemaker implantation, and mortality. Interestingly, both high and low extremes of the PR duration are associated with AF risk. However, the results regarding PR prolongation as a risk factor for AF are inconsistent. Some studies have analyzed the impact of P duration (as a part of the PR interval) and demonstrated that the P-duration contributes to the length of PR interval and adverse outcomes. The PR prolongation could be considered as a marker for cardiovascular degenerative aging caused by myocardial fibrosis and vascular inflammation. Furthermore, due to PR prolongation chronically raised intra-atrial pressure and consequential neuro-hormonal activation predispose systemic vascular endothelial dysfunction and explain the associations with adverse vascular events. In this review, we discuss the association between biomarkers with PR interval in AF.

  1. Risk of atrial fibrillation as a function of the electrocardiographic PR interval

    DEFF Research Database (Denmark)

    Nielsen, Jonas Bille; Pietersen, Adrian; Graff, Claus

    2013-01-01

    Prolongation of the PR interval has been associated with an increased risk of incident atrial fibrillation (AF).......Prolongation of the PR interval has been associated with an increased risk of incident atrial fibrillation (AF)....

  2. AQUIFER PROTIST RESPONSE AND THE POTENTIAL FOR TCE BIOREMEDIATION WITH BURKHOLDERIA CEPACIA G4 PR1

    Science.gov (United States)

    The introduction of bacteria into the environment for bioremediation purposes (bioaugmentation) requires analysis and monitoring of the persistence and activity of microbial population for efficacy and risk assessment purposes. Burkholderia cepacia G4 PR123 and PR131 constitutive...

  3. Er aftalelovens § 36 internationalt præceptiv?

    DEFF Research Database (Denmark)

    Sørensen, Eric Aa.; Werlauff, Erik

    2014-01-01

    underlagt fremmed ret som følge af parternes vedtagelse. Særligt analyseres det, i hvilket omfang aftalelovens § 36 kan kvalificeres som internationalt ufravigelig, og dette besvares benægtende. Udviklingen i EU, både lovgivningsmæssigt og i retspraksis, viser, at en internationalt præceptiv regel skal...... varetage en almen interesse, og at det således ikke er tilstrækkeligt, at en regel udelukkende varetager stærke private interesser. I lighed med fransk og tysk retspraksis kan en regel som aftalelovens § 36 derfor ikke anses for at være internationalt præceptiv....

  4. Lessons Learned from PR and PP Case Study

    Energy Technology Data Exchange (ETDEWEB)

    Bley, D.C. [Buttonwood Consulting, Inc., 11738 English Mill Court, Oakton, VA 22124 (United States)

    2009-06-15

    The Generation-IV International Forum (GIF) working group on proliferation resistance and physical protection (PR and PP) has developed a methodology for evaluating the PR and PP effectiveness of Gen-IV nuclear energy systems. A number of applications studies culminating in the 2008-2009 Case Study have been helpful in developing the methodology, and in testing its ease of use and ability to provide useful information to designers and policy/decision makers. This paper examines the lessons learned from these studies. The applications studies evaluated a set of PR and PP measures for an 'Example Sodium Fast Reactor' (ESFR), a hypothetical design incorporating many features of anticipated Gen-IV energy systems. The objectives of the 2008- 2009 Case Study were to exercise the GIF PR and PP Methodology for a complete Gen-IV reactor/fuel cycle system; to demonstrate, via the comparison of different design options, that the methodology can generate meaningful results for designers and decision makers; to provide examples of PR and PP evaluations for future users; to facilitate transition to other studies; and to facilitate other ongoing collaborative efforts (e.g., INPRO) and associated efforts (e.g., GNEP). We will explain how the Case Study met these goals. PR Lessons Learned. We found that completeness in 'diversion' pathways can be ensured and that a set of diversion pathway segments can be developed along with proliferation resistance measures for each pathway. The examination of 'misuse' found that misuse, for achieving weapons-usable fissile material, is a complex process, i.e., it is not a single action on a single piece of equipment, but rather an integrated exploitation of various assets and system elements. We found that 'breakout' is a modifying strategy within the diversion and misuse threats and takes various forms that depend upon intent and aggressiveness, and ultimately the proliferation time assumed by a

  5. HyPR Device: Mobile Support for Hybrid Patient Records

    DEFF Research Database (Denmark)

    Houben, Steven; Frost, Mads; Bardram, Jakob E

    2014-01-01

    The patient record is one of the central artifacts in medical work that is used to organize, communicate and coordinate important information related to patient care. In many hospitals a double record consisting of an electronic and paper part is maintained. This practice introduces a number of c......PR device decreases configuration work, supports mobility in clinical work and increases awareness on patient data.......The patient record is one of the central artifacts in medical work that is used to organize, communicate and coordinate important information related to patient care. In many hospitals a double record consisting of an electronic and paper part is maintained. This practice introduces a number...... introduce the HyPR Device, a device that merges the paper and electronic patient record into one system. We provide results from a clinical simulation with eight clinicians and discuss the functional, design and infrastructural requirements of such hybrid patient records. Our study suggests that the Hy...

  6. Streaming video - præsentation af trailere over internettet

    DEFF Research Database (Denmark)

    Jensen, Ole Riis; Forchhammer, Søren

    1998-01-01

    interaktiv tjeneste baseret på realtidsfremvisning af videotrailere, såkaldt streaming video og audio, og hvor brugeren kan få information om en film der tænkes udbudt på en pay-per-view kanal. Der i arbejdets forløb blevet opbygget en demo, der implementerer en sådan tjeneste.......Som et led i Tele Danmark Kabel TV's markedsføring ønsker man at kunne præsentere filmtrailere og andet materiale i form af levende billeder til kunderne via Wold Wide Web (WWW). Dette projekts hovedformål er at undersøge eksisterende metoder og udvikle redskaber til at præsentere en tilsvarende...

  7. Thermoluminescent response of LaAlO3:Pr

    International Nuclear Information System (INIS)

    Morales H, A.; Zarate M, J.; Azorin N, J.; Rivera M, T.

    2015-10-01

    In this study, the thermoluminescence response of doped lanthanum aluminate (LaAlO 3 ) with praseodymium ion (Pr) obtained by the Pechini method and drying by the spraying technique Spry Dryer was studied. The obtained powders were analyzed structurally by the X-ray diffraction technique; the morphological characterization was by the scanning electron microscopy technique. The obtained powders at 800 degrees C presented crystallinity and showed a Rhombohedral crystal structure, this phase was observed by X-ray diffraction patterns. Thermoluminescence response of LaAlO 3 :Pr showed a brightness curve with a peak centered at 157 degrees C. The sensitivity of the doped samples was improved about 90 times in comparison with the undoped sample. Thermoluminescence response in function of the wavelength showed a maximum at 230 nm, reproducibility of thermoluminescence response was ±50%. Also the fading in thermoluminescence response was studied. (Author)

  8. Level structure of 149Nd. The decay of 149Pr

    International Nuclear Information System (INIS)

    Pinston, J.A.; Roussille, R.; Sadler, G.; Tenten, W.; Bocquet, J.P.; Pfeiffer, B.; Warner, D.D.

    1977-01-01

    The decay of 149 Pr (Tsub(1/2) = 2.2 min) has been studied using the two fission product separators JOSEF and LOHENGRIN to produce the 149 Pr nucleus. A level scheme for 149 Nd has been established. The β-branching of log ft values for the excited levels were deduced from the analysis of γ-intensity balances. Furthermore, the spins and parities for most of the excited states observed were obtained from the comparison between the present work, the neutron capture results and the pick-up reactions. The positive parity levels have been described with the Nilsson model with Coriolis and ΔN = 2 interactions included. The properties of the negative parity states cannot be explained as easily; however, it has been attempted to extract the structure of the ground state and the first excited states. (orig.) [de

  9. PR-strategia pienelle vaatebrändille : Case: Arela

    OpenAIRE

    Keskitalo, Aino

    2016-01-01

    Opinnäytetyön lähtökohtana oli laatia pienelle vaatebrändille PR-strategia, jota yritys voi hyödyntää jatkossa. Yhteistyöyritys tässä työssä oli suomalainen Arela, joka tunnetaan erityisesti laadukkaista kašmirneuleistaan. PR-strategian laatimisen tarkoituksena on antaa Arelalle työkaluja, jotka voivat auttaa brändiä saamaan lisää näkyvyyttä etenkin printti- ja verkkolehdissä sekä sosiaalisessa mediassa. Lisäksi sen tavoitteena on lisätä yleisesti brändin tunnettuutta ja luoda positiivista mi...

  10. Precision-Recall-Gain Curves:PR Analysis Done Right

    OpenAIRE

    Flach, Peter; Kull, Meelis

    2015-01-01

    Precision-Recall analysis abounds in applications of binary classification where true negatives do not add value and hence should not affect assessment of the classifier's performance. Perhaps inspired by the many advantages of receiver operating characteristic (ROC) curves and the area under such curves for accuracy-based performance assessment, many researchers have taken to report Precision-Recall (PR) curves and associated areas as performance metric. We demonstrate in this paper that thi...

  11. Iran : Præstestyret - under udvikling eller afvikling

    DEFF Research Database (Denmark)

    Rahigh-Aghsan, Ali

    2010-01-01

    Man hører ikke længere om gadeprotester i Teheran. Efter de voldsomme kampe i Teheran først på året, er det tilsyneladende lykkedes den Islamiske Republik at tvinge oppositionen til tavshed. Ifølge lederen af 'den grønne bevægelse' og tidligere præsidentkandidat, Mousavi, er det islamiske regimes...

  12. CERN’s Prévessin site post office

    CERN Multimedia

    2016-01-01

    The post office at CERN’s Prévessin site (Building 866) is open Monday to Thursday from 9.30 a.m. to 12.30 p.m. for the following services:   Sending parcels Purchasing stamps Sending money: postal money order/express international money order Telephone contacts: Internal: 77071 From Switzerland: +41 22 767 7071 From France: 04 50 40 75 54

  13. Emociones y prácticas ante una contingencia sanitaria

    Directory of Open Access Journals (Sweden)

    Anna Fernández Poncela

    2009-12-01

    Full Text Available En este trabajo reflexionamos en torno a la relación entre emociones y cultura, sentimientos, discursos y prácticas sociales. Un ejemplo de caso: la contingencia sanitaria en México causada por el virus de influenza humana A H1N1 en la primavera del año 2009.  Fecha de recepción: 13 octubre 2009. Fecha de aceptación: 22 de noviembre 2009.

  14. Managing your brand career management and personal PR for librarians

    CERN Document Server

    Still, Julie

    2015-01-01

    Managing Your Brand: Career Management and Personal PR for Librarians sets out guidelines for developing career pathways, including options for career change and the exploration of community service, as an avenue that can provide new opportunities. The text allows librarians at all levels to maximize their talents, providing them with career planning strategies that will facilitate professional development and personal satisfaction. Early chapters provide advice and strategies to readers, with later chapters addressing working relationships, librarianship, scholarship, and other forms

  15. Les approches multisectorielles pour prévenir les grossesses ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Ce projet vise à générer, à travers une recherche opérationnelle, des connaissances sur le phénomène des grossesses précoces et de développer des stratégies multisectorielles, centrées sur les adolescents et prenant en compte les acteurs du système de l'éducation, de la santé, du milieu judiciaire et des communautés.

  16. Pascal e o amor-próprio

    Directory of Open Access Journals (Sweden)

    Jean-Robert Armogathe

    2006-12-01

    Full Text Available Uma abordagem lexográfica do amor próprio nos escritos de Pascal: carta (1651 sobre a morte de seu pai, frag. La 978 e nove ocorrências nos Pensamentos. A partir dos diferentes "amores-próprios" enumerados pela tradição, o amor-próprio natural de Adão, anterior à Queda, que para Tomás de Aquino é indiferente, é identificado por Jansenius como pervertido em concupiscência. Em sua Apologia, Pascal segue a linha jansenista de um modo tão radical que os teólogos de Port-Royal julgaram preciso mitigar seus sentimentos a ponto de contradizê-lo, como fez Nicole, que descreveu o amor-próprio como um substituto hipocrítico do comportamento virtuoso.A lexicological approach of self-love in Pascal’s writings: letter (1651 about his father’s death, frag. La 978 and nine occurrences in the Pensées. From the different "self-loves" enumerated by the tradition, Adam’s natural self-love, before the Fall, which is indifferent for Thomas Aquinas, is identified by Jansenius as perverted into concupiscentia. In his Apology, Pascal follows the Jansenist line, in such a radical way that the Port-Royal theologians found necessary to mitigate his feelings, up to contradict him, like Nicole did, who described self-love as a hypocritical substitute to virtuous behaviour.

  17. Pesquisa como instrumento da prática

    Directory of Open Access Journals (Sweden)

    Maura Maria Guimarães de Almeida

    1995-06-01

    Full Text Available O trabalho aborda a utilização da pesquisa como instrumento da prática profissional da enfermaria na área de assistência, administração e ensino. Situa a ciência como processo. Ressalta a responsabilidade da enfermeira na produção da conhecimento científico. Destaca os fatores que dificultam e facilitam a pesquisa, além dos aspectos éticos envolvidos.

  18. Public Relations: Ketchum brands new product with innovative PR strategy.

    Science.gov (United States)

    2006-01-01

    Novartis Pharmaceuticals tapped publis relations (PR) giant Ketchum earlier this year to spearhead a marketing campaign that would make its new U.S. Food and Drug Administration-approved prescription-based medication, Enablex, stand out among the crowd in over active bladder (OAB) treatment. OAB is a disorder that affects an estimated 33 million Americans making this treatment highly in demand with consumers and highly competitive with other pharmaceutical companies.

  19. Kampanye Pr Radio Ssfm “Assik Ala Ssfm”

    OpenAIRE

    Putra, Jeffry Septian; Setiabudi, Djoko; Naryoso, Agus

    2013-01-01

    JUDUL : Kampanye PR Radio SSFM “Assik Ala SSFM”NAMA : Jeffry Septian PutraNIM : D2C607024ABSTRAKSIPersaingan radio saat ini semakin ketat, industri media siaran perlu memahamidan mengenali ekspektasi atau apa yang diinginkan para pendengar. Pengelola radioperlu strategi untuk mendapatkan perhatian dari para pendengarnya terlebih dari sisipemasaran yang akan memberikan dampak bagi kelancaran merebut perhatianpendengar. Untuk menciptakan strategi yang tepat dalam membuat mengelola radioagar tet...

  20. Soft mode and magnetic phase transition in PrNi

    International Nuclear Information System (INIS)

    Alekseev, P.A.; Lazukov, V.N.; Sadikov, I.P.; Klement'ev, E.S.; Allenspach, P.; Chumlyakov, Yu.I.

    2002-01-01

    The spectrum of the magnetic excitation of the PrNi intermetallic compound monocrystal is studied through the neutrons inelastic scattering. Essential softening of certain collective modes of the magnetic excitation near the temperature of the ferromagnetic ordering T c ∼ 20 K is identified. The above result is analyzed from the viewpoint of the model, describing the magnetic phase transition in the systems with the directed magnetic moment [ru

  1. Purification and Fibrillation of Full-Length Recombinant PrP

    OpenAIRE

    Makarava, Natallia; Baskakov, Ilia V.

    2012-01-01

    Misfolding and aggregation of prion protein (PrP) is related to several neurodegenerative diseases in humans such as Creutzfeldt–Jacob disease, fatal familial insomnia, and Gerstmann–Straussler–Sheinker disease. Certain applications in prion area require recombinant PrP of high purity and quality. Here, we report an experimental procedure for expression and purification of full-length mammalian PrP. This protocol has been proved to yield PrP of extremely high purity that lac...

  2. Boosted protease inhibitors and the electrocardiographic measures of QT and PR durations

    DEFF Research Database (Denmark)

    Soliman, Elsayed Z; Lundgren, Jens D; Roediger, Mollie P

    2011-01-01

    There are contradictory reports regarding the effects of protease inhibitors on the ECG measures of QT and PR interval durations. The effect of interrupting use of protease inhibitors on QT and PR progression is also unknown.......There are contradictory reports regarding the effects of protease inhibitors on the ECG measures of QT and PR interval durations. The effect of interrupting use of protease inhibitors on QT and PR progression is also unknown....

  3. French post office on the Prévessin Site

    CERN Multimedia

    Relations with the Host States Service

    2006-01-01

    The French postal authorities have informed CERN that, as of 1 April 2006, their office on the Prévessin site will be placed under the administrative responsibility of the Saint-Genis-Pouilly branch, directed by Mrs Marina Combe. The main changes this reorganisation will entail for customers relate to the office's opening hours. As of 2 May 2006, the post office on the Prévessin site will be open to the public, Monday to Friday, from 9.00 a.m. to 12.30 p.m. and from 1.30 p.m. to 3.30 p.m. From 3 April 2006 onwards, the office will also have two financial advisers available from 12 o'clock noon to 3.00 p.m., or by appointment. For further information, please contact the Prévessin site post office on 77071. Relations with the Host States Service http://www.cern.ch/relations/ relations.secretariat@cern.ch Tel. 72848

  4. Alimentation et précarité / food and insecurity

    Directory of Open Access Journals (Sweden)

    Laurence Tibère

    2008-10-01

    Full Text Available La précarité entraîne des modifications des pratiques alimentaires quotidiennes, avec de possibles conséquences sur l’état de santé. Si certains travaux mettent l’accent sur les risques de dénutrition, d’autres insistent sur l’augmentation des cas d’obésité. Cet article, qui s’appuie sur des données empiriques collectées dans le cadre d’une recherche conduite en 2002 sur l’alimentation des Français et la corpulence, met en évidence l’intérêt de distinguer différents niveaux de précarité, pour comprendre leur impact sur les pratiques et représentations alimentaires d’une part et sur la prévalence de l’obésité d’autre part.Financial insecurity can lead to significant changes in daily eating habits and dietary models, with disturbing consequences on health. Some scientists focus on the risks of malnutrition, others on the increase in obesity. This paper is based on empirical findings from a study on French eating habits conducted in 2002. It underlines the importance of distinguishing between different levels of insecurity as a means of understanding its impact on eating behaviours on the one hand and obesity on the other.

  5. Implications of HIV PrEP Trials Results

    Science.gov (United States)

    Anton, Peter; Fletcher, Courtney V.; DeGruttola, Victor; McGowan, Ian; Becker, Stephen; Zwerski, Sheryl; Burns, David

    2011-01-01

    Abstract Six randomized clinical trials have been implemented to examine the efficacy of tenofovir disoproxil fumarate (TDF) and/or TDF/emtricitabine (TDF/FTC) as preexposure prophylaxis for HIV-1 infection (PrEP). Although largely complementary, the six trials have many similar features. As the earliest results become available, an urgent question may arise regarding whether changes should be made in the conduct of the other trials. To consider this in advance, a Consultation on the Implications of HIV Pre-Exposure Prophylaxis (PrEP) Trials Results sponsored by the Division of AIDS (DAIDS) of the National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), and the Bill and Melinda Gates Foundation (BMGF) was held on January 29, 2010, at the Natcher Conference Center, NIH, Bethesda, MD. Participants included basic scientists, clinical researchers (including investigators performing the current PrEP trials), and representatives from the U.S. Food and Drug Administration (FDA) and the agencies sponsoring the trials: the U.S. Centers for Disease Control and Prevention (CDC), the U.S. Agency for International Development (USAID), the BMGF, and the U.S. NIH. We report here a summary of the presentations and highlights of salient discussion topics from this workshop. PMID:20969483

  6. A Common Opinion on Croatian Journalists Tested by PR Profesionals

    Directory of Open Access Journals (Sweden)

    Ana Sušić

    2016-06-01

    Full Text Available Journalists in Croatia do not enjoy formidable reputation among the public due to the beliefs that their writing is, inter alia, biased, inclined to sensationalism and manipulation, and that they lack analytical skills (see also Kanižaj and Skoko, 2010; Jokoš and Kanižaj, 2012. The aim of this research is to verify how journalistic work and journalistic profession in Croatia is perceived by corporate sector PR professionals who cooperate with them on a daily basis. Using the method of in-depth interviews conducted with eight PR professionals, the reputation of Croatian journalists has been put to the test. The research revealed that the interviewed PR professionals perceive Croatian journalists mostly as superficial and biased reporters who search for sensation rather than the truth. However, it turned out that the interviewees do not percieve journalists as being envious, irresponsible or corruptible. They even demonstrated true understanding of the difficulties that journalists encounter, especially in the context of the economic crisis.

  7. Urbanismo y prácticas agrícolas

    Directory of Open Access Journals (Sweden)

    Luis Octavio Da Silva

    2011-05-01

    Full Text Available Este texto presenta y discute el fenómeno del cultivo de vegetales en ámbitos urbanos. Inicialmente se aborda el tema en el campo simbólico: el concepto de paraíso, el surgimiento de la agricultura y el nacimiento de las ciudades. En un segundo momento, las prácticas de agricultura son contextualizadas en relación con las teorías utópicas. La tercera parte aborda el fenómeno de la agricultura urbana en la era industrial: la difusión de las practicas de jardinería, los jardines familiares, los jardines industriales, los jardines obreros, el autoabastecimiento urbano, la ideología de las campañas de fomento de esas actividades y, finalmente, las prácticas paisajísticas que acompañaron los proyectos urbanísticos de la era industrial. En su última parte, antes de la conclusión, el artículo esboza un breve relato y discute una práctica paisajística recurrente en los medios urbanos: el cultivo del césped, sus orígenes anglo sajones, la transposición para el medio urbano norteamericano, su simbología y los conflictos que acompañaron la difusión de ese paisaje en las ciudades de américa del norte.

  8. Prügiveo hind hakkab olenema inimesest endast / Peep Aaviksoo ; interv. Jaan Rõõmussaar

    Index Scriptorium Estoniae

    Aaviksoo, Peep, 1956-

    2004-01-01

    Ilmunud ka: Stolitsa, 5. nov. 2004, lk. 3. AS-i Tallinna Prügila taotles prügi ladestamishinna tõstmist, ettevõtlusameti hinna ja tarbijakaitse osakond pidas taotletavat hinda liiga kõrgeks. Tallinna abilinnapea vastab küsimustele prügimajanduse kota

  9. Quantitating PrP Polymorphisms Present in Prions from Heterozygous Scrapie-Infected Sheep.

    Science.gov (United States)

    Silva, Christopher J; Erickson-Beltran, Melissa L; Hui, Colleen; Badiola, Juan José; Nicholson, Eric M; Requena, Jesús R; Bolea, Rosa

    2017-01-03

    Scrapie is a prion (PrP Sc ) disease of sheep. The incubation period of sheep scrapie is strongly influenced by polymorphisms at positions 136, 154, and 171 of a sheep's normal cellular prion protein (PrP C ). Chymotrypsin was used to digest sheep recombinant PrP to identify a set of characteristic peptides [M 132 LGSXMSRPL 141 (X = A or V), Y 153 XENMY 158 (X,= H or R), and Y 166 RPVDXY 172 (X = H, K, Q, or R)] that could be used to detect and quantitate polymorphisms at positions 136, 154, and 171 of sheep PrP C or PrP Sc . These peptides were used to develop a multiple reaction monitoring method (MRM) to detect the amounts of a particular polymorphism in a sample of PrP Sc isolated from sheep heterozygous for their PrP C proteins. The limit of detection for these peptides was less than 50 attomole. Spinal cord tissue from heterozygous (ARQ/VRQ or ARH/ARQ) scrapie-infected Rasa Aragonesa sheep was analyzed using this MRM method. Both sets of heterozygotes show the presence of both polymorphisms in PrP Sc . This was true for samples containing both proteinase K (PK)-sensitive and PK-resistant PrP Sc and samples containing only the PK-resistant PrP Sc . These results show that heterozygous animals contain PrP Sc that is composed of significant amounts of both PrP polymorphisms.

  10. 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...

  11. Computational identification of novel PR-1-type genes in Oryza sativa

    Indian Academy of Sciences (India)

    Figure 3 shows a phylogenetic tree of PR-1 amino acid se- quences. In this tree, PR-1 proteins in Arabidopsis, tobacco, pepper, maize, wheat and barley were selected as reference data. In addition, the Schizophyllum commune PR-1 protein. (pSc7) was used as the outgroup sequence. The phylogenetic tree shows that ...

  12. 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...

  13. Prügi tekkekohas sortimise kavatsus on läbi kukkunud / Anti Ronk

    Index Scriptorium Estoniae

    Ronk, Anti

    2004-01-01

    Korteriühistute ja prügifirmade kogemuste kohaselt ei ole Eesti inimesed harjunud prügi sorteerima ega kasuta vastavaid konteinereid. Kommentaarid Lauka korteriühistu eksjuhilt Nelli Vahemetsalt ja Ragn-Sellsi müügijuhilt Maren Pärnalt. Lisa: Prügi

  14. Interaction between 14-3-3β and PrP influences the dimerization of 14-3-3 and fibrillization of PrP106-126.

    Science.gov (United States)

    Han, Jun; Song, Qin-Qin; Sun, Peng; Zhang, Jin; Wang, Xu; Song, Juan; Li, Gong-Qi; Liu, Ying-Hui; Mei, Guo-Yong; Shi, Qi; Tian, Chan; Chen, Cao; Gao, Chen; Zhao, Bo; Dong, Xiao-Ping

    2014-02-01

    Proteins of the 14-3-3 family are universal participate in multiple cellular processes. However, their exact role in the pathogenesis of prion diseases remains unclear. In this study, we proposed that human PrP was able to form molecular complex with 14-3-3β. The domains responsible for the interactions between PrP and 14-3-3β were mapped at the segments of amino acid (aa) residues 106-126 within PrP and aa 1-38 within 14-3-3β. Homology modeling revealed that the key aa residues for molecular interaction were D22 and D23 in 14-3-3β as well as K110 in PrP. Mutations in these aa residues inhibited the interaction between the two proteins in vitro. Our results also showed that recombinant PrP encouraged 14-3-3β dimer formation, whereas PrP106-126 peptide inhibited it. Recombinant 14-3-3β disaggregated the mature PrP106-126 fibrils in vitro. Moreover, the PrP-14-3-3 protein complexes were observed in the brain tissues of normal and scrapie agent 263K infected hamsters. Colocalization of PrP and 14-3-3 was seen in the cytoplasm of human neuroblastoma cell line SH-SY5Y, as well as human cervical cancer cell line HeLa transiently expressing full-length human PrP. Our current data suggest the neuroprotection of PrPC and neuron damage caused by PrPSc may be associated with their functions of 14-3-3 dimerization regulation. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. Thermoluminescent response of LaAlO{sub 3}:Pr; Respuesta termoluminiscente de LaAlO{sub 3}:Pr

    Energy Technology Data Exchange (ETDEWEB)

    Morales H, A.; Zarate M, J. [Universidad Michoacana de San Nicolas de Hidalgo, Instituto de Investigacion en Metalurgia y Materiales, Ciudad Universitaria, Edif. U, 58060 Morelia, Michoacan (Mexico); Azorin N, J. [Universidad Autonoma Metropolitana, Unidad Iztapalapa, Av. San Rafael Atlixco 186, Col. Vicentina, 09340 Mexico D. F. (Mexico); Rivera M, T., E-mail: feyo_yo@hotmail.com [IPN, Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada, Av. Legaria 694, 11500 Mexico D. F. (Mexico)

    2015-10-15

    In this study, the thermoluminescence response of doped lanthanum aluminate (LaAlO{sub 3}) with praseodymium ion (Pr) obtained by the Pechini method and drying by the spraying technique Spry Dryer was studied. The obtained powders were analyzed structurally by the X-ray diffraction technique; the morphological characterization was by the scanning electron microscopy technique. The obtained powders at 800 degrees C presented crystallinity and showed a Rhombohedral crystal structure, this phase was observed by X-ray diffraction patterns. Thermoluminescence response of LaAlO{sub 3}:Pr showed a brightness curve with a peak centered at 157 degrees C. The sensitivity of the doped samples was improved about 90 times in comparison with the undoped sample. Thermoluminescence response in function of the wavelength showed a maximum at 230 nm, reproducibility of thermoluminescence response was ±50%. Also the fading in thermoluminescence response was studied. (Author)

  16. La práctica/estilo de vida swinger: ¿una práctica social-sexual perversa?

    Directory of Open Access Journals (Sweden)

    Johnny Javier Orejuela

    Full Text Available Este artículo reflexiona, desde una perspectiva interdisciplinar -sociología, antropología y psicoanálisis- sobre la práctica swinger en tanto estilo de vida en la ciudad de Cali, Colombia. Esta connotación de lo swinger, como una práctica que permite el establecimiento del lazo social con sentido, lleva a cuestionar una percepción moralizante y prejuiciosa de la misma, compartida no sólo por personas que la consideran como una transgresión del deber ser de la sexualidad, sino también por profesionales del campo "psi", que la califican como perversa. El texto discute ambas posturas, que parecen desconocer las inflexiones resultantes de las actuales transformaciones de la intimidad.

  17. Cytosolic PrP Can Participate in Prion-Mediated Toxicity

    Science.gov (United States)

    Thackray, Alana M.; Zhang, Chang; Arndt, Tina

    2014-01-01

    ABSTRACT Prion diseases are characterized by a conformational change in the normal host protein PrPC. While the majority of mature PrPC is tethered to the plasma membrane by a glycosylphosphatidylinositol anchor, topological variants of this protein can arise during its biosynthesis. Here we have generated Drosophila transgenic for cytosolic ovine PrP in order to investigate its toxic potential in flies in the absence or presence of exogenous ovine prions. While cytosolic ovine PrP expressed in Drosophila was predominantly detergent insoluble and showed resistance to low concentrations of proteinase K, it was not overtly detrimental to the flies. However, Drosophila transgenic for cytosolic PrP expression exposed to classical or atypical scrapie prion inocula showed a faster decrease in locomotor activity than similar flies exposed to scrapie-free material. The susceptibility to classical scrapie inocula could be assessed in Drosophila transgenic for panneuronal expression of cytosolic PrP, whereas susceptibility to atypical scrapie required ubiquitous PrP expression. Significantly, the toxic phenotype induced by ovine scrapie in cytosolic PrP transgenic Drosophila was transmissible to recipient PrP transgenic flies. These data show that while cytosolic PrP expression does not adversely affect Drosophila, this topological PrP variant can participate in the generation of transmissible scrapie-induced toxicity. These observations also show that PrP transgenic Drosophila are susceptible to classical and atypical scrapie prion strains and highlight the utility of this invertebrate host as a model of mammalian prion disease. IMPORTANCE During prion diseases, the host protein PrPC converts into an abnormal conformer, PrPSc, a process coupled to the generation of transmissible prions and neurotoxicity. While PrPC is principally a glycosylphosphatidylinositol-anchored membrane protein, the role of topological variants, such as cytosolic PrP, in prion-mediated toxicity and

  18. Pr4N2S3 and Pr4N2Se3: two non-isostructural praseodymium(iii) nitride chalcogenides

    International Nuclear Information System (INIS)

    Lissner, Falk; Schleid, Thomas

    2005-01-01

    The non-isostructural nitride chalcogenides of praseodymium, Pr 4 N 2 S 3 and Pr 4 N 2 Se 3 , are formed by the reaction of the praseodymium metal with sodium azide (NaN 3 ), praseodymium trihalide (PrX 3 ; X = Cl, Br, I) and the respective chalcogen (sulfur or selenium) at 900 C in evacuated silica ampoules after seven days. Both crystallize monoclinically in space group C2/c (Pr 4 N 2 S 3 : a = 1788.57(9), b = 986.04(5), c = 1266.49(6) pm, β = 134.546(7) , Z = 8; Pr 4 N 2 Se 3 : a = 1311.76(7), b = 1017.03(5), c = 650.42(3) pm, β = 90.114(6) , Z = 4). The crystal structures of both compounds show a layered construction, dominated by N 3- -centred (Pr 3+ ) 4 tetrahedra which share a common edge first. Continuing linkage of the so resulting bitetrahedral [N 2 Pr 6 ] 12+ units via the non-connected vertices to layers according to [stack ∞ 2 ]{[N(Pr) 2/2 e (Pr') 2/2 v ] 3+ } forms different kinds of tetrahedral nets which can be described as layers consisting of ''four- and eight-rings'' for Pr 4 N 2 S 3 and as layers of ''six-rings'' for Pr 4 N 2 Se 3 . Whereas the crystal structure of Pr 4 N 2 S 3 exhibits four different Pr 3+ cations with coordination numbers of six (2 x) and seven (2 x) against N 3- and S 2- , the number of cations in the nitride selenide (Pr 4 N 2 Se 3 ) is reduced to half (Pr1 and Pr2) also having six- and sevenfold anionic coordination spheres. Further motifs for the connection of [NM 4 ] 9+ tetrahedra in crystal structures of nitride chalcogenides and halides of the rare-earth elements with ratios of N: M = 1: 2 are presented and discussed. (Abstract Copyright [2005], Wiley Periodicals, Inc.) [de

  19. Prévention des grossesses précoces au Bénin : développement d ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Ce projet de recherche action vise à réduire les grossesses précoces au Benin à travers le développement et la promotion d'une intervention innovante et basée sur les données probantes, conciliant la santé sexuelle et reproductive, l'estime de soi et l'autonomisation des adolescents. Au Bénin, les adolescents et les ...

  20. 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

  1. Desnutrição e práticas pré-escolares de leitura e escrita

    Directory of Open Access Journals (Sweden)

    Sandra Maria Sawaya

    2013-01-01

    Full Text Available O presente artigo procura dar conta de alguns dos resultados de uma pesquisa realizada com um grupo de treze crianças de três a cinco anos em uma instituição de educação infantil que atende crianças com desnutrição primária. Um dos objetivos do estudo foi verificar que relações e práticas de leitura e escrita se desenvolvem entre esse grupo de crianças e seu professor na pré-escola. Os dados obtidos corroboram estudos que apontam a necessidade de revisar os pressupostos das políticas educacionais de que as crianças de camadas populares trazem para a instituição de ensino problemas de aprendizagem devido a atrasos no desenvolvimento linguístico e cognitivo em decorrência da ausência de práticas de leitura e escrita em seu universo sociocultural.

  2. HIV-negative male couples' attitudes about pre-exposure prophylaxis (PrEP) and using PrEP with a sexual agreement.

    Science.gov (United States)

    Mitchell, Jason W; Lee, Ji-Young; Woodyatt, Cory; Bauermeister, José; Sullivan, Patrick; Stephenson, Rob

    2016-08-01

    One efficacious strategy to help prevent HIV is oral pre-exposure prophylaxis (PrEP), a daily regimen of antiretroviral treatment taken by HIV-negative individuals. Two of the recommendations of Centers for Disease Control and Prevention (CDC) guidelines for PrEP pertain to being in a relationship (i.e., male couples). Despite the recognition of how primary partners in male couples' relationships shape HIV risk and CDC's PrEP guidelines, there is a paucity of data that examine HIV-negative male couples' attitudes toward PrEP use and using PrEP with a sexual agreement. A sexual agreement is an explicit agreement made between two individuals about what sex and other related behaviors may occur within and outside of their relationship. In this qualitative study, we examine HIV-negative male couples' attitudes toward PrEP use and whether they thought PrEP could be integrated into a sexual agreement. Data for this study are drawn from couple-level interviews conducted in 2014 with 29 HIV-negative male couples who had a sexual agreement and were from Atlanta or Detroit. Both passive (e.g., flyers) and active (e.g., targeted Facebook advertisements) recruitment methods were used; the sample was stratified by agreement type. Thematic analysis was applied to identify the following themes regarding HIV-negative male couples' attitudes toward PrEP use: (1) PrEP and condom use; (2) concerns about PrEP (e.g., effectiveness, side effects, and promoting sexually risky behavior); and (3) accessibility of PrEP. Some thought PrEP could be a part of couples' agreement because it could help reduce sexual anxiety and sexual risk, and would help keep the couple safe. Others described PrEP use with an agreement as something for "others". Some were also concerned that incorporating PrEP could usurp the need for a sexual agreement in a couples' relationship. These themes highlight the need to improve informational messaging and promotion efforts about PrEP among HIV-negative male couples

  3. 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.

  4. 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.

  5. Electron spin resonance of Gd in the nuclear cooling agent: PrNi5 single crystals

    International Nuclear Information System (INIS)

    Levin, R.; Davidov, D.; Grayevsky, A.; Shaltiel, D.; Zevin, V.

    1980-01-01

    The ESR of Gd in single crystals of PrNi 5 is observed to exhibit significant angular dependence of the resonance position and linewidth at low temperatures. This is interpreted in terms of the axial spin Hamiltonian which takes the anisotropic susceptibility and the Gd-Pr exchange into consideration. From lineshape analysis the axial crystal field parameter and isotropic Gd-Pr exchange are derived. The Gd ESR linewidth increases with temperature; the thermal broadening is angularly dependent. This is similar to that observed for the Pr NMR in PrNi 5 single crystals. Both the NMR and ESR thermal broadenings are attributed to low-frequency fluctuations of the Pr ions induced by the Pr-Pr exchange coupling. A model for hexagonal Van-Vleck compounds is given and with the linewidth enables the Pr-Pr exchange coupling, under the assumption of a Gaussian or a Lorenzian distribution of the low-frequency fluctuation spectra, to be extracted. It is suggested that the angular dependence of the ESR thermal broadening is due to the Gd-Pr exchange coupling. (UK)

  6. The thermodynamic characteristics of vaporization in the NaI-PrI3 system

    Science.gov (United States)

    Motalov, V. B.; Kudin, L. S.; Markus, T.

    2009-05-01

    The vaporization of the NaI-PrI3 quasi-binary system was studied by high-temperature mass spectrometry over the whole concentration range. At 623-994 K, saturated vapor contained not only (NaI) n and (PrI3) n molecules ( n = 1, 2) and Na+(NaI) n ( n = 0-4) and I-(PrI3) n ( n = 1-2) ions but also mixed molecular and ionic associates recorded for the first time (NaPrI4, Na2PrI5, NaPrI{3/+}, Na2PrI{4/+}, Na3PrI{5/+}, Na4PrI{6/+}, NaPrI{5/-}, and NaPr2I{8/-}). The partial vapor pressures of molecules were calculated, and the equilibrium constants of the dissociation of neutral and charged associates were measured. The enthalpies of molecular and ion-molecular reactions were determined, and the enthalpies of formation of gaseous molecules and ions were obtained.

  7. Competencias del Maestro Mentor de Prácticas

    Directory of Open Access Journals (Sweden)

    Carmen MEGIA CUELLIGA

    2015-12-01

    Full Text Available Este artículo es el resultado de un proceso de investigación centrado en la figura del maestro mentor de prácticas. La finalidad del artículo persigue determinar e identificar las competencias profesionales clave que deben tener asumidas y adquiridas y que contribuyen a la formación de los futuros maestros, cuando éstos realizan el periodo de prácticas de magisterio. Por otra parte, queremos explorar cómo se sienten de preparados y formados los maestros mentores para el ejercicio de su labor de mentor. Los objetivos específicos se centran en:Determinar cuáles son las competencias que deben tener asumidas y adquiridas para formar al futuro maestro. Contribuir a la formación de los maestros mentores para el desempeño de sus funciones. En el estudio se ha utilizado una metodología de carácter cuantitativo. Se ha elaborado un cuestionario con escala tipo Likert que se ha aplicado a los maestros mentores de colegios de toda la Comunidad de Madrid con el fin de recoger la mayor información posible sobre las competencias específicas desempeñadas por los mentores durante el periodo de prácticas de enseñanza de los futuros maestros. Participaron 105 colegios durante el curso 2012-2013. La muestra real participante de maestros mentores está constituida por 674. La fiabilidad del cuestionario se obtuvo mediante el alpha de Cronbach con fiabilidad del 0,859, en los bloques: el mentor y el centro escolar, por una parte, y, por otra, el mentor y el desarrollo de competencias específicas docentes del alumno en prácticas. Se utilizó para el análisis de resultados el programa estadístico SPSS 20.0, la prueba de contraste mediante ANOVA y para el análisis de segmentación se utilizó el método de crecimiento CHAID para identificar el nivel de satisfacción de los mentores con respecto a su formación y capacidad para ejercer su función de mentor. Entre los hallazgos encontrados destacamos la importancia de la relación entre el

  8. Canto pré-natal: alquimias sonoras para gestantes

    Directory of Open Access Journals (Sweden)

    Janaina Trasel Martins

    2017-10-01

    Full Text Available Este artigo irá focar no canto pré-natal; nos benefícios da música e do canto durante a gestação; na audição do feto no ventre e na escuta da gestante do seu corpo. Como metodologia para pesquisar sobre estes temas foram realizados estudos teóricos nas áreas da musicoterapia obstétrica, da terapia sonora e da medicina e também foram realizadas práticas de canto pré-natal. Arte, movimento e saúde são integrados com as alquimias sonoras para ampliar a consciência da corporeidade da mulher durante a gestação. Com cantos femininos em um círculo de mulheres, nos apoiamos e nos fortalecemos durante a gestação e enviamos vibrações sonoras harmoniosas para o bebê no ventre. ABSTRACT This article will focus on prenatal singing; on the benefits of music and singing during pregnancy; on the baby's hearing in the womb and on the listening of the pregnant woman to her body. To determine the methodology for researching these themes, theoretical studies were done in obstetrical music therapy, sound therapy, medicine and also practical research in prenatal singing classes. Art, movement and health are integrated with sound alchemy to widen the woman’s body awareness during pregnancy. With feminine chants in a circle of women, we support and strengthen ourselves during pregnancy and we send harmonious sounds vibrations to the baby in the womb. KEYWORDS Prenatal singing, prenatal music, pregnancy, listening, consciousness.

  9. The thermodynamics of Pr55Gag-RNA interaction regulate the assembly of HIV.

    Directory of Open Access Journals (Sweden)

    Hanumant S Tanwar

    2017-02-01

    Full Text Available The interactions that occur during HIV Pr55Gag oligomerization and genomic RNA packaging are essential elements that facilitate HIV assembly. However, mechanistic details of these interactions are not clearly defined. Here, we overcome previous limitations in producing large quantities of full-length recombinant Pr55Gag that is required for isothermal titration calorimetry (ITC studies, and we have revealed the thermodynamic properties of HIV assembly for the first time. Thermodynamic analysis showed that the binding between RNA and HIV Pr55Gag is an energetically favourable reaction (ΔG<0 that is further enhanced by the oligomerization of Pr55Gag. The change in enthalpy (ΔH widens sequentially from: (1 Pr55Gag-Psi RNA binding during HIV genome selection; to (2 Pr55Gag-Guanosine Uridine (GU-containing RNA binding in cytoplasm/plasma membrane; and then to (3 Pr55Gag-Adenosine(A-containing RNA binding in immature HIV. These data imply the stepwise increments of heat being released during HIV biogenesis may help to facilitate the process of viral assembly. By mimicking the interactions between A-containing RNA and oligomeric Pr55Gag in immature HIV, it was noted that a p6 domain truncated Pr50Gag Δp6 is less efficient than full-length Pr55Gag in this thermodynamic process. These data suggest a potential unknown role of p6 in Pr55Gag-Pr55Gag oligomerization and/or Pr55Gag-RNA interaction during HIV assembly. Our data provide direct evidence on how nucleic acid sequences and the oligomeric state of Pr55Gag regulate HIV assembly.

  10. Interferon-Stimulated Genes Are Transcriptionally Repressed by PR in Breast Cancer.

    Science.gov (United States)

    Walter, Katherine R; Goodman, Merit L; Singhal, Hari; Hall, Jade A; Li, Tianbao; Holloran, Sean M; Trinca, Gloria M; Gibson, Katelin A; Jin, Victor X; Greene, Geoffrey L; Hagan, Christy R

    2017-10-01

    The progesterone receptor (PR) regulates transcriptional programs that drive proliferation, survival, and stem cell phenotypes. Although the role of native progesterone in the development of breast cancer remains controversial, PR clearly alters the transcriptome in breast tumors. This study identifies a class of genes, Interferon (IFN)-stimulated genes (ISGs), potently downregulated by ligand-activated PR which have not been previously shown to be regulated by PR. Progestin-dependent transcriptional repression of ISGs was observed in breast cancer cell line models and human breast tumors. Ligand-independent regulation of ISGs was also observed, as basal transcript levels were markedly higher in cells with PR knockdown. PR repressed ISG transcription in response to IFN treatment, the canonical mechanism through which these genes are activated. Liganded PR is robustly recruited to enhancer regions of ISGs, and ISG transcriptional repression is dependent upon PR's ability to bind DNA. In response to PR activation, key regulatory transcription factors that are required for IFN-activated ISG transcription, STAT2 and IRF9, exhibit impaired recruitment to ISG promoter regions, correlating with PR/ligand-dependent ISG transcriptional repression. IFN activation is a critical early step in nascent tumor recognition and destruction through immunosurveillance. As the large majority of breast tumors are PR positive at the time of diagnosis, PR-dependent downregulation of IFN signaling may be a mechanism through which early PR-positive breast tumors evade the immune system and develop into clinically relevant tumors. Implications: This study highlights a novel transcriptional mechanism through which PR drives breast cancer development and potentially evades the immune system. Mol Cancer Res; 15(10); 1331-40. ©2017 AACR . ©2017 American Association for Cancer Research.

  11. Oxidation of Helix-3 methionines precedes the formation of PK resistant PrP.

    Directory of Open Access Journals (Sweden)

    Tamar Canello

    2010-07-01

    Full Text Available While elucidating the peculiar epitope of the alpha-PrP mAb IPC2, we found that PrPSc exhibits the sulfoxidation of residue M213 as a covalent signature. Subsequent computational analysis predicted that the presence of sulfoxide groups at both Met residues 206 and 213 destabilize the alpha-fold, suggesting oxidation may facilitate the conversion of PrPC into PrPSc. To further study the effect of oxidation on prion formation, we generated pAbs to linear PrP peptides encompassing the Helix-3 region, as opposed to the non-linear complexed epitope of IPC2. We now show that pAbs, whose epitopes comprise Met residues, readily detected PrPC, but could not recognize most PrPSc bands unless they were vigorously reduced. Next, we showed that the alpha-Met pAbs did not recognize newly formed PrPSc, as is the case for the PK resistant PrP present in lines of prion infected cells. In addition, these reagents did not detect intermediate forms such as PK sensitive and partially aggregated PrPs present in infected brains. Finally, we show that PrP molecules harboring the pathogenic mutation E200K, which is linked to the most common form of familial CJD, may be spontaneously oxidized. We conclude that the oxidation of methionine residues in Helix-3 represents an early and important event in the conversion of PrPC to PrPSc. We believe that further investigation into the mechanism and role of PrP oxidation will be central in finally elucidating the mechanism by which a normal cell protein converts into a pathogenic entity that causes fatal brain degeneration.

  12. 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.

  13. S1PR3 Signaling Drives Bacterial Killing and Is Required for Survival in Bacterial Sepsis.

    Science.gov (United States)

    Hou, JinChao; Chen, QiXing; Wu, XiaoLiang; Zhao, DongYan; Reuveni, Hadas; Licht, Tamar; Xu, MengLong; Hu, Hu; Hoeft, Andreas; Ben-Sasson, Shmuel A; Shu, Qiang; Fang, XiangMing

    2017-12-15

    Efficient elimination of pathogenic bacteria is a critical determinant in the outcome of sepsis. Sphingosine-1-phosphate receptor 3 (S1PR3) mediates multiple aspects of the inflammatory response during sepsis, but whether S1PR3 signaling is necessary for eliminating the invading pathogens remains unknown. To investigate the role of S1PR3 in antibacterial immunity during sepsis. Loss- and gain-of-function experiments were performed using cell and murine models. S1PR3 levels were determined in patients with sepsis and healthy volunteers. S1PR3 protein levels were up-regulated in macrophages upon bacterial stimulation. S1pr3 -/- mice showed increased mortality and increased bacterial burden in multiple models of sepsis. The transfer of wild-type bone marrow-derived macrophages rescued S1pr3 -/- mice from lethal sepsis. S1PR3-overexpressing macrophages further ameliorated the mortality rate of sepsis. Loss of S1PR3 led to markedly decreased bacterial killing in macrophages. Enhancing endogenous S1PR3 activity using a peptide agonist potentiated the macrophage bactericidal function and improved survival rates in multiple models of sepsis. Mechanically, the reactive oxygen species levels were decreased and phagosome maturation was delayed in S1pr3 -/- macrophages due to impaired recruitment of vacuolar protein-sorting 34 to the phagosomes. In addition, S1RP3 expression levels were elevated in monocytes from patients with sepsis. Higher levels of monocytic S1PR3 were associated with efficient intracellular bactericidal activity, better immune status, and preferable outcomes. S1PR3 signaling drives bacterial killing and is essential for survival in bacterial sepsis. Interventions targeting S1PR3 signaling could have translational implications for manipulating the innate immune response to combat pathogens.

  14. 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

  15. Use of Social Media in PR: A Change of Trend

    OpenAIRE

    Tang Mui Joo; Chan Eang Teng

    2016-01-01

    The use of social media has become more defined. It has been widely used for the purpose of business. More marketers are now using social media as tools to enhance their businesses. Whereas on the other hand, there are more and more people spending their time through mobile apps to be engaged in the social media sites like YouTube, Facebook, Twitter and others. Social media has even become common in Public Relations (PR). It has become number one platform for creating and sharing content. In ...

  16. Prévessin site – Pedestrian and cycle entrances

    CERN Multimedia

    GS-DI

    2014-01-01

    Entrances for pedestrians and cyclists on Route du Maroc and on Chemin du Moulin des Ponts, in Prévessin, will be re-opened:   from 7 April to 31 October 2014, from 7.00 a.m. to 9.00 a.m. and from 5.00 p.m. to 7.00 p.m. on working days (Monday to Friday).   IMPORTANT: all users must show their access cards to the security guard as a matter of course when passing through the gates, both on entering and leaving the site.

  17. Picnic zone booking at Prévessin site

    CERN Multimedia

    TS Department

    2005-01-01

    We would like to inform you that from now on, bookings of the picnic zone on the Prévessin site (next to building 910) have to be done via the "Conference Room Booking System", already used for conference room booking.  To do this, please use the following Web site: http://booking.cern.ch:9000/cr/java/guest/welcomecrbs, select "Pre-book a room", choose "ZONE BAR B Q" and fill in all information requested. You will receive a confirmation by e-mail as soon as your booking has been accepted.   TS Department - FM Group

  18. Práticas alimentares no primeiro ano de vida

    OpenAIRE

    Lima, Ana Paula Esmeraldo; Javorski, Marly; Vasconcelos, Maria Gorete Lucena de

    2011-01-01

    O estudo buscou analisar a literatura publicada referente às práticas alimentares no primeiro ano de vida de filhos de mães adolescentes, por meio de uma revisão integrativa nas bases de dados Lilacs, Medline e Cochrane, no período de 2000 a 2010. Foram utilizadas as palavras-chave: adolescente, aleitamento materno, alimentação mista e nutrição do lactente, sendo selecionados onze artigos científicos, que compuseram a amostra do estudo. Os resultados apontaram a incipiência de pesquisas publi...

  19. Prácticas docentes y mejora de la escuela

    OpenAIRE

    Rodríguez Trujillo, Nacarid

    2007-01-01

    Las instituciones superiores de formación docente en países con evidentes debilidades en el funcionamiento del sistema escolar oficial requieren encontrar modos de incrementar sus aportes al mejoramiento de la calidad de la educación en los niveles básicos. Las prácticas docentes constituyen una especial oportunidad para estos fines, ampliando su concepción y desarrollo más allá de la preparación y dictado de clases en las escuelas. Sistematizamos una experiencia guiada por la intención...

  20. Prévision avec des copules en finance

    OpenAIRE

    Charpentier , Arthur

    2015-01-01

    Cet article présente un survol les techniques usuelles de modélisation de séries nancières multiples. Pus spéciquement, on cherchera a obtenir une extention multivariée des modèles GARCH. Dans un premier temps, nous verrons comment modéliser la dynamique de la matrice de corrélation (conditionnelle), puis nous verrons comment généraliser cette approche à des lois conditionnelles plus générales, construites à l'aide de copules (et s'aranchir ainsi de l'hypothese de lois elliptiques). Les princ...

  1. Präanalytik zur HCMV-Diagnostik

    OpenAIRE

    Travers-Podmaniczky, Gabrielle

    2011-01-01

    Die kongenitale HCMV-Infektion ist der wichtigste Auslöser geistiger Retardierung viraler Genese und ist für die meisten neurosensorischen Hörstörungen nicht genetischen Ursprunges verantwortlich. Die Entwicklung neuer Strategien zur Prävention der HCMV-Infektion bei Neugeborenen ist also von höchster Dringlichkeit. Die Einführung von universellen Screeningprogrammen bei Neugeborenen könnte die frühzeitige Erkennung einer Infektion und somit einen frühen therapeutischen Einsatz ermöglichen. U...

  2. Prévessin site: Pedestrian and cycle entrance

    CERN Multimedia

    2015-01-01

    The entrance to the Prévessin site for pedestrians and cyclists on Chemin du Moulin des Ponts will be re-opened: from 7 April to 30 October 2015, from 7.00 a.m. to 9.00 a.m. and from 5.00 p.m. to 7.00 p.m. on working days (Monday to Friday).   IMPORTANT: all users must show their access cards to the security guard as a matter of course when passing through the gates, both on entering and leaving the site.

  3. Optical imaging of borehole PR10 at Olkiluoto 2006

    International Nuclear Information System (INIS)

    Tarvainen, A.-M.

    2007-03-01

    Suomen Malmi Oy carried out optical imaging of borehole PR10 at Olkiluoto site in Eurajoki during December 2006. The survey is a part of Posiva Oy's detailed investigation program for the final disposal of spent nuclear fuel. The assignment included the field work and the data processing. This report describes the field operation, the equipment as well as the processing procedures and shows the obtained results and their quality. The raw and processed data are delivered digitally in WellCAD and PDF format. (orig.)

  4. Pr:YLF orange laser investigation at cryogenic temperature

    Czech Academy of Sciences Publication Activity Database

    Fibrich, Martin; Šulc, J.; Jelínková, H.

    2015-01-01

    Roč. 12, č. 9 (2015), 1-23, č. článku 095801. ISSN 1612-2011 R&D Projects: GA MŠk ED1.1.00/02.0061 Grant - others:ELI Beamlines(XE) CZ.1.05/1.1.00/02.0061 Institutional support: RVO:68378271 Keywords : Pr:YLF * diode pumping * InGaN laser diode * cryogenic temperature Subject RIV: BH - Optics, Masers, Laser s Impact factor: 2.391, year: 2015

  5. Crescimento pró-pobre no Brasil: impactos regionais

    OpenAIRE

    França, João Mário Santos de

    2007-01-01

    Esta pesquisa científica foi apresentada como trabalho de conclusão do curso de Doutorado em Economia e reúne três artigos na área de crescimento. O primeiro deles utiliza a metodologia desenvolvida por Kakwani, Khabdker e Son (2004) para analisar a existência de crescimento “pró-pobre” nas regiões brasileiras nos anos de 1995 a 2005. Foram utilizados como suporte medidas de pobreza P(0), P(1) e P(2) e o índice de GINI. Os resultados apontam que tais políticas causaram maior impacto nas regiõ...

  6. 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

  7. PR-EDB: Power Reactor Embrittlement Database Version 3

    International Nuclear Information System (INIS)

    Wang, Jy-An John; Subramani, Ranjit

    2008-01-01

    The aging and degradation of light-water reactor pressure vessels is of particular concern because of their relevance to plant integrity and the magnitude of the expected irradiation embrittlement. The radiation embrittlement of reactor pressure vessel materials depends on many factors, such as neutron fluence, flux, and energy spectrum, irradiation temperature, and preirradiation material history and chemical compositions. These factors must be considered to reliably predict pressure vessel embrittlement and to ensure the safe operation of the reactor. Large amounts of data from surveillance capsules are needed to develop a generally applicable damage prediction model that can be used for industry standards and regulatory guides. Furthermore, the investigations of regulatory issues such as vessel integrity over plant life, vessel failure, and sufficiency of current codes, Standard Review Plans (SRPs), and Guides for license renewal can be greatly expedited by the use of a well-designed computerized database. The Power Reactor Embrittlement Database (PR-EDB) is such a comprehensive collection of data for U.S. designed commercial nuclear reactors. The current version of the PR-EDB lists the test results of 104 heat-affected-zone (HAZ) materials, 115 weld materials, and 141 base materials, including 103 plates, 35 forgings, and 3 correlation monitor materials that were irradiated in 321 capsules from 106 commercial power reactors. The data files are given in dBASE format and can be accessed with any personal computer using the Windows operating system. 'User-friendly' utility programs have been written to investigate radiation embrittlement using this database. Utility programs allow the user to retrieve, select and manipulate specific data, display data to the screen or printer, and fit and plot Charpy impact data. The PR-EDB Version 3.0 upgrades Version 2.0. The package was developed based on the Microsoft .NET framework technology and uses Microsoft Access for

  8. Verminderung der Prüfungsangst durch Modellernen im Klassenzimmer

    OpenAIRE

    Ellgring, Johann Heinrich; Elbing, Eberhard

    2010-01-01

    Die Wirksamkeit des Modellernens im Klassenzimmer zur Veränderung der Prüfungsangst wurde bei 152 Knaben und 164 Mädchen der Klassen 5-8 einer Hauptschule untersucht. Den Schülern wurden die Angst-Skalen (TASe und GASC) von Sarason vorgelegt. Anhand der Fragebogenergebnisse wurden die Kinder den Kategorien "hochängstlich" (HA), "mittelängstlich" (MA) und "niedrigängstlich" (NA) zugeordnet. Für 3,5 Monate wurden die folgenden Paarbildungen (Banknachbarn) beibehalten: HA neben HA, MA und NA, NA...

  9. PR-EDB: Power Reactor Embrittlement Database - Version 3

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jy-An John [ORNL; Subramani, Ranjit [ORNL

    2008-03-01

    The aging and degradation of light-water reactor pressure vessels is of particular concern because of their relevance to plant integrity and the magnitude of the expected irradiation embrittlement. The radiation embrittlement of reactor pressure vessel materials depends on many factors, such as neutron fluence, flux, and energy spectrum, irradiation temperature, and preirradiation material history and chemical compositions. These factors must be considered to reliably predict pressure vessel embrittlement and to ensure the safe operation of the reactor. Large amounts of data from surveillance capsules are needed to develop a generally applicable damage prediction model that can be used for industry standards and regulatory guides. Furthermore, the investigations of regulatory issues such as vessel integrity over plant life, vessel failure, and sufficiency of current codes, Standard Review Plans (SRPs), and Guides for license renewal can be greatly expedited by the use of a well-designed computerized database. The Power Reactor Embrittlement Database (PR-EDB) is such a comprehensive collection of data for U.S. designed commercial nuclear reactors. The current version of the PR-EDB lists the test results of 104 heat-affected-zone (HAZ) materials, 115 weld materials, and 141 base materials, including 103 plates, 35 forgings, and 3 correlation monitor materials that were irradiated in 321 capsules from 106 commercial power reactors. The data files are given in dBASE format and can be accessed with any personal computer using the Windows operating system. "User-friendly" utility programs have been written to investigate radiation embrittlement using this database. Utility programs allow the user to retrieve, select and manipulate specific data, display data to the screen or printer, and fit and plot Charpy impact data. The PR-EDB Version 3.0 upgrades Version 2.0. The package was developed based on the Microsoft .NET framework technology and uses Microsoft Access for

  10. PrP0\\0 mice show behavioral abnormalities that suggest PrPC has a role in maintaining the cytoskeleton.

    Science.gov (United States)

    Background/Introduction. PrPC is highly conserved among mammals, but its natural function is unclear. Prnp ablated mice (PrP0/0) appear to develop normally and are able to reproduce. These observations seem to indicate that the gene is not essential for viability, in spite of it being highly conse...

  11. PrP aggregation can be seeded by pre-formed recombinant PrP amyloid fibrils without the replication of infectious prions.

    Science.gov (United States)

    Barron, Rona M; King, Declan; Jeffrey, Martin; McGovern, Gillian; Agarwal, Sonya; Gill, Andrew C; Piccardo, Pedro

    2016-10-01

    Mammalian prions are unusual infectious agents, as they are thought to consist solely of aggregates of misfolded prion protein (PrP). Generation of synthetic prions, composed of recombinant PrP (recPrP) refolded into fibrils, has been utilised to address whether PrP aggregates are, indeed, infectious prions. In several reports, neurological disease similar to transmissible spongiform encephalopathy (TSE) has been described following inoculation and passage of various forms of fibrils in transgenic mice and hamsters. However, in studies described here, we show that inoculation of recPrP fibrils does not cause TSE disease, but, instead, seeds the formation of PrP amyloid plaques in PrP-P101L knock-in transgenic mice (101LL). Importantly, both WT-recPrP fibrils and 101L-recPrP fibrils can seed plaque formation, indicating that the fibrillar conformation, and not the primary sequence of PrP in the inoculum, is important in initiating seeding. No replication of infectious prions or TSE disease was observed following both primary inoculation and subsequent subpassage. These data, therefore, argue against recPrP fibrils being infectious prions and, instead, indicate that these pre-formed seeds are acting to accelerate the formation of PrP amyloid plaques in 101LL Tg mice. In addition, these data reproduce a phenotype which was previously observed in 101LL mice following inoculation with brain extract containing in vivo-generated PrP amyloid fibrils, which has not been shown for other synthetic prion models. These data are reminiscent of the "prion-like" spread of aggregated forms of the beta-amyloid peptide (Aβ), α-synuclein and tau observed following inoculation of transgenic mice with pre-formed seeds of each misfolded protein. Hence, even when the protein is PrP, misfolding and aggregation do not reproduce the full clinicopathological phenotype of disease. The initiation and spread of protein aggregation in transgenic mouse lines following inoculation with pre

  12. Low fraction of the 222K PrP variant in the protease-resistant moiety of PrPres in heterozygous scrapie positive goats.

    Science.gov (United States)

    Mazza, Maria; Guglielmetti, Chiara; Ingravalle, Francesco; Brusadore, Sonia; Langeveld, Jan P M; Ekateriniadou, Loukia V; Andréoletti, Olivier; Casalone, Cristina; Acutis, Pier Luigi

    2017-07-01

    The presence of lysine (K) at codon 222 has been associated with resistance to classical scrapie in goats, but few scrapie cases have been identified in 222Q/K animals. To investigate the contribution of the 222K variant to PrPres formation in natural and experimental Q/K scrapie cases, we applied an immunoblotting method based on the use of two different monoclonal antibodies, F99/97.6.1 and SAF84, chosen for their different affinities to 222K and 222Q PrP variants. Our finding that PrPres seems to be formed nearly totally by the 222Q variant provides evidence that the 222K PrP variant confers resistance to conversion to PrPres formation and reinforces the view that this mutation has a protective role against classical scrapie in goats.

  13. Archaeometric exploration at Akköprü in Ankara

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    Ali Akın Akyol

    2013-01-01

    Full Text Available The archaeometric exploration was conducted by surveying and sampling studies on the stone, and mortar samples from Akköprü in Ankara. Spot salt test and conductometric analysis were applied to get water soluble salt content of stone samples. The aggregate and binder part of the mortars were determined by the analyses of acidic aggregate & binder, aggregate granulometry, thin section optic microscopy and X-ray diffraction. In addition, the physical conditions of the stones were determined by some physical tests. The results of archaeometrical data showed that the constructive stone material was mainly andesite besides ignimbrite and dacite, and the original binder material was lime mortar. The cement content of the binder of mortars reveals the recent interventions on Akköprü. In the light of petrographic studies it was understood that the source of the original constructive raw material reflects the local formation. The high soluble salt content and the bad physical conditions of some stones also showed that they are undergoing a decomposition process of different degrees.

  14. Prácticas discursivas orales, dialectos e identidad social

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    ÉDER GARCÍA-DUSSÁN

    2015-01-01

    Full Text Available Este artículo explica unas categorías que auxilian la descripción y el análisis de los mundos gestual y corp-oral, con el fin de aprovecharlas en beneficio del desarrollo de una tesis conocida en sociolingüística: las lenguas viven en las prácticas discursivas y reflejan elementos socioculturales de sus hablantes. De esta suerte, al conocer fenómenos, en cualquier nivel de la lengua, hay posibilidades más seguras hacia la comprensión profunda de los rasgos de una cultura. Esta tesis se pone a prueba con dos ejemplos, frecuentes en la comunicación entre colombianos, un gesto-batuta y una conducta corporal frente a espacios urbanos, y se concluye desde dos dimensiones: (i una teórica, que revela la posibilidad de ratificar cómo el análisis de los niveles de la lengua son también el vehículo de la búsqueda de claves sobre la identidad social de un pueblo, y (ii una práctica que reitera una cualidad social local: la interacción violenta entre socios y la consecuente imposibilidad de la armonía y la paz sociales, asentada en la imagen del fuerte, del hombre vigoroso y valiente.

  15. Escribir las Prácticas. Foucault, de Certeau, Marin.

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    MARCELO MELLA POLANCO

    2011-10-01

    Full Text Available Este libro de Chartier, publicado por primera vez en 1996, se organiza a partir de la recopilación de cuatro ensayos del autor presentados como ponencias en las Universidades de Buenos Aires y Mar del Plata. Los propósitos centrales que ligan a cada uno de estos trabajos consisten, por una parte, en dilucidar dimensiones de la relación entre discurso (discursos y prácticas sociales; por otra, en  contribuir a la actualización del oficio del historiador como una práctica de construcción de relatos en diálogo con otros saberes. Particularmente, este autor busca analizar como se desarrolla la “construcción social de los discursos” y la “construcción discursiva del mundo social”; contribuir a complejizar la perspectiva de análisis de la dominación y los mecanismos de resistencia y; ampliar, mediante el estudio de las obras de Foucault, de Certeau y Marin, los límites de la disciplina histórica.

  16. Research into the evaluation of PR activities in companies from Serbia

    Directory of Open Access Journals (Sweden)

    Milan Nikolic

    2016-04-01

    Full Text Available This paper presents the results of a research into the volume, type and quality of the evaluation of public relations activities in companies in Serbia. The survey was conducted via a web survey. The responses were collected from 50 PR service managers from 50 companies in Serbia. The results are presented through descriptive statistics and correlation analysis where some of the observed sizes of the connection were analyzed. The main conclusions can be summarized as follows: PR functions are often not assigned sufficient importance in companies in Serbia; the evaluation of PR activity is slightly neglected compared to other PR activities; intensive and continuous evaluation of the performances of PR activities increases the likelihood of the complete PR function of the company being successful; companies that are not so successful use evaluation less than successful companies; the evaluation of PR activities is mostly done through a method for measuring quantity; the main problems in the evaluation of PR activities are lack of time and money. The evaluation of PR activities in companies in Serbia can be improved through a greater understanding on the part of top managers, and also by hiring additional PR practitioners.

  17. 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.

  18. Family planning providers' role in offering PrEP to women.

    Science.gov (United States)

    Seidman, Dominika; Weber, Shannon; Carlson, Kimberly; Witt, Jacki

    2018-03-09

    Pre-exposure prophylaxis (PrEP) provides a radically different HIV prevention option for women. Not only is PrEP the first discrete, woman-controlled method that is taken in advance of exposure, but it is both safe and highly effective, offering over 90% protection if taken daily. While multiple modalities of PrEP are in development ranging from vaginal rings to injectables and implants, only PrEP with oral tenofovir/emtricitabine is currently FDA-approved. Family planning clinics provide key access points for many women to learn about and obtain PrEP. By incorporating PrEP services into family planning care, family planning providers have the opportunity to meet women's expectations, ensure women are aware of and offered comprehensive HIV prevention options, and reverse emerging disparities in PrEP access. Despite real and perceived barriers to integrating PrEP into family planning care, providing PrEP services, ranging from education to onsite provision, is not only possible but an important component of providing high-quality sexual and reproductive healthcare to women. Lessons learned from early adopters will help guide those in family planning settings initiating or enhancing PrEP services. Copyright © 2018. Published by Elsevier Inc.

  19. Mass spectrometric investigation of neutral and charged constituents in saturated vapor over PrI3

    International Nuclear Information System (INIS)

    Motalov, V.B.; Vorobiev, D.E.; Kudin, L.S.; Markus, T.

    2009-01-01

    The Knudsen effusion mass spectrometric technique was used to study vapor species over praseodymium triiodide. The monomer, PrI 3 , and dimer, Pr 2 I 6 , molecules and the negative ions, PrI 4 - and Pr 2 I 7 - , were observed in saturated vapor in the temperature range from 856 K to 1048 K. The partial vapor pressures of neutral constituents were determined and the enthalpies of sublimation obtained using the second and the third laws of thermodynamics (Δ s H deg. (298.15 K) = 291 ± 4 kJ mol -1 for PrI 3 , and Δ s H deg. (298.15 K) = 400 ± 30 kJ mol -1 for Pr 2 I 6 ). The equilibrium constants for various ion molecular reactions were measured and the enthalpies of reactions obtained. The enthalpies of formation, Δ f H deg. (298.15 K) kJ mol -1 , of gaseous molecules and ions were calculated and are as follows: -374 ± 6 (PrI 3 ), -929 ± 30 (Pr 2 I 6 ), -867 ± 30 (PrI 4 - ), -1432 ± 50 (Pr 2 I 7 - )

  20. Le Cyrano de Bergerac de Jacques Prévot

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    Madeleine Alcover

    2012-04-01

    Full Text Available Dans son dernier ouvrage consacré à Cyrano, J. Prévot se borne, généralement, à répéter ce qu’il a exposé en 1977-1978. Pour ce qui est de la biographie, des pans entiers lui échappent ou sont laissés dans l’ombre, dont particulièrement deux relatifs à la religion et à l’armée. La mise en lumière de la lignée maternelle de l’écrivain a révélé, en 2000, un milieu de dévots très influents dans la Compagnie du Saint-Sacrement et, plus récemment, la découverte de l’allégeance du grand-père paternel au protestantisme (même pas mentionnée montre une tension idéologique au sein de la famille et éclaire d’un jour nouveau les commentaires répétés de Cyrano sur les dogmes de l’église catholique. Sur la vie militaire de l’auteur, les maigres informations fournies datent de 1858 (Lacroix et de 1921 (Lachèvre ; mais nous savons aujourd’hui que Cyrano a entretenu des relations suivies avec son capitaine aux Gardes du roi, Alexandre de Biran de Castegeloux (le « Carbon de Casteljaloux » de Rostand, domicilié soit à Clamart, tout près de Mauvières, soit à Paris, rue de la Verrerie où l’on trouve aussi Le Bret et Cyrano dès 1649 ; Castelgeloux était très lié à Jean de Cuigy, le notaire secrétaire du roi qui signa les lettres patentes de l’édition posthume des Etats et Empires de la Lune, domicilié dans le même quartier, ainsi que son ancien ami Tanneguy Regnault des Boisclairs, dernier protecteur de Cyrano. Il y a là tout un réseau d’amis influents et de longue date, qui tissent les fils d’une vie jusqu’ici présentée comme totalement décousue. Quant à l’histoire des textes, et particulièrement la « bibliographie matérielle », Prévot soit ignore totalement soit ne comprend pas en quoi consiste une censure après la publication ou « cartonnage » (Lettres de 1654 puis dédicace et préface, signées Le Bret, des Etats et Empires de la Lune en 1657 et ne voit pas

  1. The Role of Shed PrPc in the Neuropathogenesis of HIV Infection.

    Science.gov (United States)

    Megra, Bezawit W; Eugenin, Eliseo A; Berman, Joan W

    2017-07-01

    HIV-1 enters the CNS soon after peripheral infection and causes chronic neuroinflammation and neuronal damage that leads to cognitive impairment in 40-70% of HIV-infected people. The nonpathogenic cellular isoform of the human prion protein (PrP c ) is an adhesion molecule constitutively expressed in the CNS. Previously, our laboratory showed that shed PrP c (sPrP c ) is increased in the cerebrospinal fluid of HIV-infected people with cognitive deficits as compared with infected people with no impairment. In this article, we demonstrate that CCL2 and TNF-α, inflammatory mediators that are elevated in the CNS of HIV-infected people, increase shedding of PrP c from human astrocytes by increasing the active form of the metalloprotease ADAM10. We show that the consequence of this shedding can be the production of inflammatory mediators, because treatment of astrocytes with rPrP c increased secretion of CCL2, CXCL-12, and IL-8. Supernatants from rPrP c -treated astrocytes containing factors produced in response to this treatment, but not rPrP c by itself, cause increased chemotaxis of both uninfected and HIV-infected human monocytes, suggesting a role for sPrP c in monocyte recruitment into the brain. Furthermore, we examined whether PrP c participates in glutamate uptake and found that rPrP c decreased uptake of this metabolite in astrocytes, which could lead to neurotoxicity and neuronal loss. Collectively, our data characterize mediators involved in PrP c shedding and the effect of this sPrP c on monocyte chemotaxis and glutamate uptake from astrocytes. We propose that shedding of PrP c could be a potential target for therapeutics to limit the cognitive impairment characteristic of neuroAIDS. Copyright © 2017 by The American Association of Immunologists, Inc.

  2. Methamphetamine increases Prion Protein and induces dopamine-dependent expression of protease resistant PrPsc.

    Science.gov (United States)

    Ferrucci, M; Ryskalin, L; Biagioni, F; Gambardella, S; Busceti, C L; Falleni, A; Lazzeri, G; Fornai, F

    2017-07-01

    The cellular prion protein (PrPc) is physiologically expressed within selective brain areas of mammals. Alterations in the secondary structure of this protein lead to scrapie-like prion protein (PrPsc), which precipitates in the cell. PrPsc has been detected in infectious, inherited or sporadic neurodegenerative disorders. Prion protein metabolism is dependent on autophagy and ubiquitin proteasome. Despite not being fully elucidated, the physiological role of prion protein relates to chaperones which rescue cells under stressful conditions.Methamphetamine (METH) is a widely abused drug which produces oxidative stress in various brain areas causing mitochondrial alterations and protein misfolding. These effects produce a compensatory increase of chaperones while clogging cell clearing pathways. In the present study, we explored whether METH administration modifies the amount of PrPc. Since high levels of PrPc when the clearing systems are clogged may lead to its misfolding into PrPsc, we further tested whether METH exposure triggers the appearance of PrPsc. We analysed the effects of METH and dopamine administration in PC12 and striatal cells by using SDS-PAGE Coomassie blue, immune- histochemistry and immune-gold electron microscopy. To analyze whether METH administration produces PrPsc aggregates we used antibodies directed against PrP following exposure to proteinase K or sarkosyl which digest folded PrPc but misfolded PrPsc. We fond that METH triggers PrPsc aggregates in DA-containing cells while METH is not effective in primary striatal neurons which do not produce DA. In the latter cells exogenous DA is needed to trigger PrPsc accumulation similarly to what happens in DA containing cells under the effects of METH. The present findings, while fostering novel molecular mechanisms involving prion proteins, indicate that, cell pathology similar to prion disorders can be mimicked via a DA-dependent mechanism by a drug of abuse.

  3. Kosmotropic anions promote conversion of recombinant prion protein into a PrPSc-like misfolded form.

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    Rodrigo Diaz-Espinoza

    Full Text Available Prions are self-propagating proteins involved in transmissible spongiform encephalopaties in mammals. An aberrant conformation with amyloid-like features of a cell surface protein, termed prion protein (PrP, is thought to be the essential component of the infectious particle, though accessory co-factor molecules such as lipids and nucleotides may be involved. The cellular co-factors and environmental conditions implicated in PrP misfolding are not completely understood. To address this issue, several studies have been done inducing misfolding of recombinant PrP (recPrP into classical amyloid structures using partially denaturing conditions. In this work, we report that misfolding of recPrP into PrP(Sc-like aggregates can be induced by simply incubating the protein in the presence of kosmotropic salts at concentrations that are known to retain or increase the stability of the protein. We used a simple experimental reaction (protein, buffer and salts submitted to agitation/incubation cycles at physiological temperature and pH. The formation of protease resistant-recPrP was time and salt-concentration dependent and required the presence of kosmotropic anions such as F(- or SO(4(-2. The molecular weights of the protease resistant recPrP fragments are reminiscent of those found in degradation assays of bona fide PrP(Sc. The aggregates also exhibited PrP(Sc-like ultrastructural features including rod-shape morphology under electron microscope, high beta-sheet content and thioflavin-T positive signal. The formation of recPrP aggregates with PrP(Sc biochemical features under conditions closer to physiological in the absence of organic co-factor molecules provides a simple setup that may prove helpful to understand the molecular mechanism of PrP misfolding.

  4. Na+/K+-ATPase is present in scrapie-associated fibrils, modulates PrP misfolding in vitro and links PrP function and dysfunction.

    Directory of Open Access Journals (Sweden)

    James F Graham

    Full Text Available Transmissible spongiform encephalopathies are characterised by widespread deposition of fibrillar and/or plaque-like forms of the prion protein. These aggregated forms are produced by misfolding of the normal prion protein, PrP(C, to the disease-associated form, PrP(Sc, through mechanisms that remain elusive but which require either direct or indirect interaction between PrP(C and PrP(Sc isoforms. A wealth of evidence implicates other non-PrP molecules as active participants in the misfolding process, to catalyse and direct the conformational conversion of PrP(C or to provide a scaffold ensuring correct alignment of PrP(C and PrP(Sc during conversion. Such molecules may be specific to different scrapie strains to facilitate differential prion protein misfolding. Since molecular cofactors may become integrated into the growing protein fibril during prion conversion, we have investigated the proteins contained in prion disease-specific deposits by shotgun proteomics of scrapie-associated fibrils (SAF from mice infected with 3 different strains of mouse-passaged scrapie. Concomitant use of negative control preparations allowed us to identify and discount proteins that are enriched non-specifically by the SAF isolation protocol. We found several proteins that co-purified specifically with SAF from infected brains but none of these were reproducibly and demonstrably specific for particular scrapie strains. The α-chain of Na(+/K(+-ATPase was common to SAF from all 3 strains and we tested the ability of this protein to modulate in vitro misfolding of recombinant PrP. Na(+/K(+-ATPase enhanced the efficiency of disease-specific conversion of recombinant PrP suggesting that it may act as a molecular cofactor. Consistent with previous results, the same protein inhibited fibrillisation kinetics of recombinant PrP. Since functional interactions between PrP(C and Na(+/K(+-ATPase have previously been reported in astrocytes, our data highlight this molecule as

  5. Quantifying the relative amounts of PrP polymorphisms present in prions isolated from heterozygous prion-infected animals

    Science.gov (United States)

    Prions cause protein misfolding diseases, such as transmissible spongiform encephalopathy. They propagate infections by converting a normal cellular prion protein into a prion (PrPSc). PrPC and PrPSc are isosequential and differ only in their respective conformations. PrPC is monomeric and sensit...

  6. PrEP implementation in the Asia-Pacific region: opportunities, implementation and barriers

    Science.gov (United States)

    Zablotska, Iryna; Grulich, Andrew E; Phanuphak, Nittaya; Anand, Tarandeep; Janyam, Surang; Poonkasetwattana, Midnight; Baggaley, Rachel; van Griensven, Frits; Lo, Ying-Ru

    2016-01-01

    Introduction HIV epidemics in the Asia-Pacific region are concentrated among men who have sex with men (MSM) and other key populations. Pre-exposure prophylaxis (PrEP) is an effective HIV prevention intervention and could be a potential game changer in the region. We discuss the progress towards PrEP implementation in the Asia-Pacific region, including opportunities and barriers. Discussion Awareness about PrEP in the Asia-Pacific is still low and so are its levels of use. A high proportion of MSM who are aware of PrEP are willing to use it. Key PrEP implementation barriers include poor knowledge about PrEP, limited access to PrEP, weak or non-existent HIV prevention programmes for MSM and other key populations, high cost of PrEP, stigma and discrimination against key populations and restrictive laws in some countries. Only several clinical trials, demonstration projects and a few larger-scale implementation studies have been implemented so far in Thailand and Australia. However, novel approaches to PrEP implementation have emerged: researcher-, facility- and community-led models of care, with PrEP services for fee and for free. The WHO consolidated guidelines on HIV testing, treatment and prevention call for an expanded access to PrEP worldwide and have provided guidance on PrEP implementation in the region. Some countries like Australia have released national PrEP guidelines. There are growing community leadership and consultation processes to initiate PrEP implementation in Asia and the Pacific. Conclusions Countries of the Asia-Pacific region will benefit from adding PrEP to their HIV prevention packages, but for many this is a critical step that requires resourcing. Having an impact on the HIV epidemic requires investment. The next years should see the region transitioning from limited PrEP implementation projects to growing access to PrEP and expansion of HIV prevention programmes. PMID:27760688

  7. Familial CJD Associated PrP Mutants within Transmembrane Region Induced Ctm-PrP Retention in ER and Triggered Apoptosis by ER Stress in SH-SY5Y Cells

    Science.gov (United States)

    Wang, Xin; Shi, Qi; Xu, Kun; Gao, Chen; Chen, Cao; Li, Xiao-Li; Wang, Gui-Rong; Tian, Chan; Han, Jun; Dong, Xiao-Ping

    2011-01-01

    Background Genetic prion diseases are linked to point and inserted mutations in the prion protein (PrP) gene that are presumed to favor conversion of the cellular isoform of PrP (PrPC) to the pathogenic one (PrPSc). The pathogenic mechanisms and the subcellular sites of the conversion are not completely understood. Here we introduce several PRNP gene mutations (such as, PrP-KDEL, PrP-3AV, PrP-A117V, PrP-G114V, PrP-P102L and PrP-E200K) into the cultured cells in order to explore the pathogenic mechanism of familial prion disease. Methodology/Principal Findings To address the roles of aberrant retention of PrP in endoplasmic reticulum (ER), the recombinant plasmids expressing full-length human PrP tailed with an ER signal peptide at the COOH-terminal (PrP-KDEL) and PrP with three amino acids exchange in transmembrane region (PrP-3AV) were constructed. In the preparations of transient transfections, 18-kD COOH-terminal proteolytic resistant fragments (Ctm-PrP) were detected in the cells expressing PrP-KDEL and PrP-3AV. Analyses of the cell viabilities in the presences of tunicamycin and brefeldin A revealed that expressions of PrP-KDEL and PrP-3AV sensitized the transfected cells to ER stress stimuli. Western blots and RT-PCR identified the clear alternations of ER stress associated events in the cells expressing PrP-KDEL and PrP-3AV that induced ER mediated apoptosis by CHOP and capase-12 apoptosis pathway. Moreover, several familial CJD related PrP mutants were transiently introduced into the cultured cells. Only the mutants within the transmembrane region (G114V and A117V) induced the formation of Ctm-PrP and caused the ER stress, while the mutants outside the transmembrane region (P102L and E200K) failed. Conclusions/Significance The data indicate that the retention of PrP in ER through formation of Ctm-PrP results in ER stress and cell apoptosis. The cytopathic activities caused by different familial CJD associated PrP mutants may vary, among them the mutants

  8. Familial CJD associated PrP mutants within transmembrane region induced Ctm-PrP retention in ER and triggered apoptosis by ER stress in SH-SY5Y cells.

    Directory of Open Access Journals (Sweden)

    Xin Wang

    Full Text Available BACKGROUND: Genetic prion diseases are linked to point and inserted mutations in the prion protein (PrP gene that are presumed to favor conversion of the cellular isoform of PrP (PrP(C to the pathogenic one (PrP(Sc. The pathogenic mechanisms and the subcellular sites of the conversion are not completely understood. Here we introduce several PRNP gene mutations (such as, PrP-KDEL, PrP-3AV, PrP-A117V, PrP-G114V, PrP-P102L and PrP-E200K into the cultured cells in order to explore the pathogenic mechanism of familial prion disease. METHODOLOGY/PRINCIPAL FINDINGS: To address the roles of aberrant retention of PrP in endoplasmic reticulum (ER, the recombinant plasmids expressing full-length human PrP tailed with an ER signal peptide at the COOH-terminal (PrP-KDEL and PrP with three amino acids exchange in transmembrane region (PrP-3AV were constructed. In the preparations of transient transfections, 18-kD COOH-terminal proteolytic resistant fragments (Ctm-PrP were detected in the cells expressing PrP-KDEL and PrP-3AV. Analyses of the cell viabilities in the presences of tunicamycin and brefeldin A revealed that expressions of PrP-KDEL and PrP-3AV sensitized the transfected cells to ER stress stimuli. Western blots and RT-PCR identified the clear alternations of ER stress associated events in the cells expressing PrP-KDEL and PrP-3AV that induced ER mediated apoptosis by CHOP and caspase-12 apoptosis pathway. Moreover, several familial CJD related PrP mutants were transiently introduced into the cultured cells. Only the mutants within the transmembrane region (G114V and A117V induced the formation of Ctm-PrP and caused the ER stress, while the mutants outside the transmembrane region (P102L and E200K failed. CONCLUSIONS/SIGNIFICANCE: The data indicate that the retention of PrP in ER through formation of Ctm-PrP results in ER stress and cell apoptosis. The cytopathic activities caused by different familial CJD associated PrP mutants may vary, among them

  9. 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

  10. Mechanoluminescence and photoluminescence of Pr3+ activated KMgF3 phosphor

    International Nuclear Information System (INIS)

    Dhoble, S.J.; Kher, R.S.; Furetta, C.

    2003-01-01

    A Czochralski method for the preparation of crystalline KMgF 3 : Pr phosphors are reported. Photoluminescence (PL) and mechanoluminescence (ML) characteristics are studied. Photoluminescence of Pr 3+ activated KMgF 3 shows the strong emission of Pr 3+ ions were observed at 498 and 650 nm by excitation of 213 mn. ML of KMgF 3 : Pr 3+ shows two peaks, which have been observed in ML intensity versus time curve. The ML peak shows the recombination of electrons with free radical (anion radical produced by γ-irradiation) released from two type traps during the mechanical pressure applied on KMgF 3 : Pr 3+ phosphor. It has a supra linear ML response with γ-ray exposure and a negligible fading. These properties of phosphor should be suitable in dosimetry of ionization relation using ML technique. Therefore the KMgF 3 : Pr 3+ phosphor proposed for ML dosimetry of ionization radiations. (Author)

  11. Green and red luminescence in co-precipitation synthesized Pr:LuAG nanophosphor

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, S. Arun; Kumar, K. Ashok; Gunaseelan, M.; Senthilselvan, J., E-mail: jsselvan@hotmail.com [Department of Nuclear Physics, University of Madras, Guindy Campus, Chennai–600 025, Tamil Nadu (India); Asokan, K. [Materials Science Group, Inter University Accelerator Centre, New Delhi-110067 (India)

    2016-05-06

    Pr:LuAG nanophosphor is an effective candidate in magnetic resonance imaging coupled positron emission tomography (MRI-PET) for medical imaging and scintillator applications. LuAG:Pr (0.05, 0.15 mol%) nanoscale ceramic powders were synthesized by co-precipitation method using urea as precipitant. Effect of antisite defect on structure and luminescence behavior was investigated. Pr:LuAG nanoceramic powders are found crystallized in cubic structure by high temperature calcination at 1400 °C and it shows antisite defect. HR-SEM analysis revealed spherically shaped Pr:LuAG nanoceramic particulate powders with ∼100 nm size. By the excitation at 450 nm, Pr:LuAG nanophosphor exhibit green to red luminescence in the wavelength range of 520 to 680 nm, which is originated from multiplet transition of Pr{sup 3+} ions.

  12. Prácticas para el desarrollo moral en universitarios

    Directory of Open Access Journals (Sweden)

    Carmen NUÉVALOS

    2009-11-01

    Full Text Available RESUMEN: Este artículo presenta una investigación que ha consistido en la elaboración y puesta en práctica de un programa de educación moral. La intervención se ha orientado al desarrollo del razonamiento moral en un grupo de jóvenes universitarios, y su diseño se inspira principalmente en la teoría de Kohlberg. Prestamos una especial atención a la práctica de la educación moral.Nuestros objetivos han sido, por un lado, entrenar a los alumnos en técnicas de desarrollo moral de cara al desempeño de su futura profesión docente. Por otro, incrementar su nivel personal de reflexión y desarrollo moral. Para la evaluación del programa hemos utilizado un método cuantitativo completado con información de tipo cualitativo.ABSTRACT: This report presents an investigation that elaborates and puts a moral education programme into practice. The intervention has been directed to develop the moral reasoning in a group of university students. Its design is founded principally in Kohlberg's theory.Our goals have been, on one hand, training the students in moral development techniques for their future teaching tasks. In the other, improving their personal reflection level and their moral development. The evaluation of the programme has been made using quantitative and qualitative methods.SOMMAIRE: Cet article présente une recherche qui a consisté en l'élaboration et la mise en pratique d'un programme d'éducation morale. Le travail est orienté vers le développement du raisonnement moral chez un groupe de jeunes universitaires en s'inspirant surtout de la théorie de Kohlberg. On vise surtout la pratique de l'éducation morale.Nos buts sont, d'un côté, l'entrainement des élèves aux techniques de développement moral en vue de leur prochain métier d'enseignants, de l'autre côté, il s'agit d'accroitre leur niveau de reflexion et de développement moral. Pour l'évaluation du programme nous avons utilisé une méthode quantitative compl

  13. Redox induces diverse effects on recombinant human wild-type PrP and mutated PrP with inserted or deleted octarepeats.

    Science.gov (United States)

    Shi, Qi; Chen, Cao; Zhang, Bao-Yun; Zhou, Wei; Xiao, Kang; Dong, Xiao-Ping

    2018-04-01

    Normal prion protein (PrP) contains two cysteines at amino acids 179 and 214, which may form intra‑ and interpeptide disulfide bonds. To determine the possible effects of this disulfide bridge on the biochemical features of PrP, prokaryotic recombinant human wild‑type PrP (PG5), and mutated PrPs with seven extra octarepeats (PG12) or with all five octarepeats removed (PG0), were subjected to redox in vitro. Sedimentation assays revealed a large portion of aggregation in redox‑treated PG5, but not in PG0 and PG12. Circular dichroism analysis detected increased β‑sheet and decreased α‑helix in PG5 subjected to redox, increased random‑coil and decreased β‑sheet in PG0, and increased random‑coil, but limited changes to β‑sheet content, in PG12. Thioflavin T fluorescence tests indicated that fluorescent value was increased in PG5 subjected to redox. In addition, proteinase K (PK) digestions indicated that PK resistance was stronger in PG12 and PG0 compared with in PG5; redox enhanced the PK resistance of all three PrP constructs, particularly PG0 and PG12. These data indicated that formation of a disulfide bond induces marked alterations in the secondary structure and biochemical characteristics of PrP. In addition, the octarepeat region within the PrP peptide markedly influences the effects of redox on the biochemical phenotypes of PrP, thus highlighting the importance of the number of octarepeats in the biological functions of PrP.

  14. 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....

  15. Allocutions et présentations du Jour 1: Ouverture et Session ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Allocutions et présentations du Jour 1: Ouverture et Session introductive. 04 novembre 2010. Jérôme Gérard. Retrouvez les documents présentés lors de la cérémonie d'ouverture et de la session introductive du Colloque ci-dessous. Interventions de la Cérémonie d'ouverture: Pr. Dieudonné OUEDRAOGO, Directeur de ...

  16. Prion Propagation in Cells Expressing PrP Glycosylation Mutants ▿

    Science.gov (United States)

    Salamat, Muhammad K.; Dron, Michel; Chapuis, Jérôme; Langevin, Christelle; Laude, Hubert

    2011-01-01

    Infection by prions involves conversion of a host-encoded cell surface protein (PrPC) to a disease-related isoform (PrPSc). PrPC carries two glycosylation sites variably occupied by complex N-glycans, which have been suggested by previous studies to influence the susceptibility to these diseases and to determine characteristics of prion strains. We used the Rov cell system, which is susceptible to sheep prions, to generate a series of PrPC glycosylation mutants with mutations at one or both attachment sites. We examined their subcellular trafficking and ability to convert into PrPSc and to sustain stable prion propagation in the absence of wild-type PrP. The susceptibility to infection of mutants monoglycosylated at either site differed dramatically depending on the amino acid substitution. Aglycosylated double mutants showed overaccumulation in the Golgi compartment and failed to be infected. Introduction of an ectopic glycosylation site near the N terminus fully restored cell surface expression of PrP but not convertibility into PrPSc, while PrPC with three glycosylation sites conferred cell permissiveness to infection similarly to the wild type. In contrast, predominantly aglycosylated molecules with nonmutated N-glycosylation sequons, produced in cells expressing glycosylphosphatidylinositol-anchorless PrPC, were able to form infectious PrPSc. Together our findings suggest that glycosylation is important for efficient trafficking of anchored PrP to the cell surface and sustained prion propagation. However, properly trafficked glycosylation mutants were not necessarily prone to conversion, thus making it difficult in such studies to discern whether the amino acid changes or glycan chain removal most influences the permissiveness to prion infection. PMID:21248032

  17. 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

  18. A STUDY OF PR PRACTITIONERS' USE OF SOCIAL MEDIA TOOLS IN CYPRUS

    OpenAIRE

    MARCOS KOMODROMOS

    2014-01-01

    This study is aimed at both researchers and public relations (PR) practitioners. The use of social media tools and technologies — such as blogs, social networking, microblogging, podcasts, etc. — is a very important factor for PR practitioners, helping them to improve important organizational processes. The research employs a mixed methodology, with data being analyzed both quantitatively and qualitatively. A sample of 25 senior PR practitioners was purposively selected from different sectors...

  19. Low fraction of the 222K PrP variant in the protease-resistant moiety of PrPres in heterozygous scrapie positive goats

    OpenAIRE

    Mazza, Maria; Guglielmetti, Chiara; Ingravalle, Francesco; Brusadore, Sonia; Langeveld, Jan P. M.; Ekateriniadou, Loukia V.; Andréoletti, Olivier; Casalone, Cristina; Acutis, Pier Luigi

    2017-01-01

    The presence of lysine (K) at codon 222 has been associated with resistance to classical scrapie in goats, but few scrapie cases have been identified in 222Q/K animals. To investigate the contribution of the 222K variant to PrPres formation in natural and experimental Q/K scrapie cases, we applied an immunoblotting method based on the use of two different monoclonal antibodies, F99/97.6.1 and SAF84, chosen for their different affinities to 222K and 222Q PrP variants. Our finding that PrPres s...

  20. Estado de conservación de la prótesis y presencia de lesiones en mucosas de pacientes portadores de prótesis parcial removible

    OpenAIRE

    Bernal Luna, Cinthya del Pilar

    2010-01-01

    Objetivo: El objetivo del presente estudio fue determinar la relación entre el estado de conservación de la prótesis y la presencia de lesiones en mucosas de pacientes portadores de prótesis parcial removible Material y método: Se realizó un estudio descriptivo, transversal y prospectivo. En este estudio se evaluaron 50 pacientes adultos (mayores de 60 años) portadores de prótesis parcial removible. Se realizó el examen clínico odontológico y se registraron los hallazgos en una fi...

  1. Prépositions et rection verbale étude des prépositions avec, contre, en, par, parmi, pour

    CERN Document Server

    Ashino, Fumitake; Paillard, Denis

    2017-01-01

    Cet ouvrage étudie une série de prépositions du français (avec, contre, par, parmi, en et pour) dont la caractéristique commune est d'introduire un terme (Y) constituant un mode d'appréhension particulier du terme (X) avec lequel ces prépositions établissent une relation (X prép Y), et dont un grand nombre d'emplois sont liés à la rection verbale.

  2. Programa Pró-Letramento : interface entre formação continuada, prática docente e ensino da leitura

    OpenAIRE

    Lúcia da Silva Cabral, Maria

    2009-01-01

    Essa pesquisa visa analisar os impactos da Formação Continuada na prática docente dos professores das séries iniciais do Ensino Fundamental no eixo do ensino da leitura, no Programa Pró-Letramento Alfabetização e Linguagem. Para realizar, então, esta investigação qualitativa, observamos os processos de Formação Continuada dos orientadores de estudos e também dos professores no programa mencionado. Realizamos também observação da prática de duas professoras em turmas iniciais ...

  3. práticas culturais contemporâneas

    Directory of Open Access Journals (Sweden)

    Mara Ambrosina Vargas

    2006-01-01

    Full Text Available El ensayo reflexivo trata sobre la muerte cerebral y la donación de órganos situándolas como prácticas culturales contemporáneas, cuyo soporte está en las teorizaciones que problematizan el cuerpo y el sujeto en la post-modernidad, en especial los estudios post-estructuralistas. Se destacan las relaciones entre las dimensiones culturales, científicas, filosóficas y jurídicas, quienes constituyen un campo de contestaciones y negociaciones, en donde ocurren las decisiones, las normas y los aparatos tecnológicos respecto a la muerte, donación y el trasplante de órganos.

  4. La docencia como práctica profesional

    Directory of Open Access Journals (Sweden)

    Martínez de Acosta Carmen H.

    1993-12-01

    Full Text Available

    No es fácil determinar si la actividad docente corresponde o no a una modalidad de práctica, rol, área de desempeño o ejercicio profesional como indiscriminadamente se denomina a las diferentes formas del quehacer de enfermería. Uno de los conceptos básicos de sociología es el de rol. El rol consiste en las conductas cumplidas o conductas percibidas como aceptables, referidas a una situación dada. La identificación de un rol se alcanza por medio de un proceso mutuo de validación y socialización profesional.

  5. Nuclear magnetic ordering in PrNi5

    International Nuclear Information System (INIS)

    Kubota, M.

    1980-11-01

    The specific heat of the hyperfine enhanced nuclear magnetic system PrNi 5 has been measured from 0.2 mK to 100 mK and in magnetic fields up to 6 T. The system was found to order at (0.40+-0.02) mK. From the study of the measured thermodynamic quantities in various magnetic fields, we obtain various information, the order at T=0 K is ferromagnetic, the hyperfine enhancement factor 1+K=(12.2+-0.5), the enhanced nuclear magnetic moment is (0.027+-0.004)μsub(B) and a nuclear exchange parameter μsub(j)Ksup(N)sub(ij)/ksub(B)=(0.20+-0.04) mK. The nature of the interactions which cause the ordering is discussed, together with the magnetic properties of the system deduced from the analysis. (orig.)

  6. Approches plurielles du quotidien. Présentation

    Directory of Open Access Journals (Sweden)

    Laurent Matthey

    2005-10-01

    Full Text Available Ce premier numéro d’Articulo – Journal of Urban Research poursuit la réflexion ouverte autour du quotidien et sa restitution dans des approches globales. Pour entretenir cette continuité, la plupart des textes mobilisent le parti pris avoué de fait social total. Cette notion — introduite par Mauss dans son Essai sur le don (1923-1924 [1995] — se relie aux préoccupations évoquées dans la quasi-totalité des textes rassemblés ici, puisque chacun offre, à sa manière, le souci de déplacer le rega...

  7. Beta decay is 151Pr into levels in 151Nd

    International Nuclear Information System (INIS)

    Shibata, Michihiro; Ikuta, Tomohiko; Taniguchi, Akihiro

    1994-01-01

    The β-decay of 59 151 Pr 92 to the levels in 60 151 Nd 91 has been studied from the fission products of 235 U using an on-line isotope separator (KUR-ISOL). Gamma-rays and conversion electrons have been measured. Conversion coefficients have been determined for the first time. The precise decay scheme is proposed up to 2430 keV. The newly observed 65 γ-rays and 16 levels are incorporated in it. The deduced level scheme of 151 Nd was compared to the calculated level scheme on the basis of the rotation-vibration coupling model with a Nilsson potential. Low-lying levels were well reproduced by this model. (author)

  8. 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 ...

  9. 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.

  10. Purification and Fibrillation of Full-Length Recombinant PrP.

    Science.gov (United States)

    Makarava, Natallia; Savtchenko, Regina; Baskakov, Ilia V

    2017-01-01

    Misfolding and aggregation of prion protein are related to several neurodegenerative diseases in humans such as Creutzfeldt-Jakob disease, fatal familial insomnia, and Gerstmann-Straussler-Scheinker disease. A growing number of applications in the prion field including assays for detection of PrP Sc and methods for production of PrP Sc de novo require recombinant prion protein (PrP) of high purity and quality. Here, we report an experimental procedure for expression and purification of full-length mammalian prion protein. This protocol has been proved to yield PrP of extremely high purity that lacks PrP adducts, oxidative modifications, or truncation, which is typically generated as a result of spontaneous oxidation or degradation. We also describe methods for preparation of amyloid fibrils from recombinant PrP in vitro. Recombinant PrP fibrils can be used as a noninfectious synthetic surrogate of PrP Sc for development of prion diagnostics including generation of PrP Sc -specific antibody.

  11. Report and analysis on 'PR and PP evaluation. Example sodium fast reactor full system case study'

    International Nuclear Information System (INIS)

    Sagara, Hiroshi; Inoue, Naoko; Kawakubo, Yoko; Watahiki, Masaru

    2011-01-01

    The Generation IV (GEN IV) Nuclear Energy Systems International Forum (GIF) Proliferation Resistance and Physical Protection Working Group (PRPP WG) was established in December 2002 in order to develop the PR and valuation methodology for GEN IV nuclear energy systems. In the final report of 'PR and PP Evaluation: Example Sodium Fast Reactor (ESFR) Full System Case Study,' issued in October 2009, the demonstration study of PR and PP evaluation with the qualitative approach are summarized using ESFR with four scenario threats. The present paper reviews and analyzes some results of the ESFR case study, and identifies the challenges and direction for the PR and PP evaluation methodology with quantitative approach. (author)

  12. 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.

  13. Electronic structure of Pr doped into superconducting Bi-Pb-Sr-Ca-Cu-O ceramics

    International Nuclear Information System (INIS)

    Egorov, A.I.; Karazhanova, G.I.; Smirnov, Yu.P.; Sovestnov, A.E.; Tyunis, A.V.; Shaburov, V.A.

    1992-07-01

    The shift of K α 1 and K β 1 X-ray lines of Pr in HTS-ceramic Bi 1.7 Pb 0.3 Sr 2-x Pr x Ca 2 Cu 3 O y (0,10≤x≤0,50, refer to PrF 3 ) are measured experimentally. The valence m(x), the charge q(x) and the 4f(x)-, 5d(x)-levels population of Pr are determined from experimental shifts. It is found that the Pr valence is near 3; the small valence increasing m≅3,04 at x=0,1 is observed. The small of Pr 5d-electron localization in ceramics in comparison with PrF 3 is revealed (∼0,1-0,2 5d-electron per Pr-atom). The probable cause of the superconductivity suppression in Y 1-x Pr xB a 2 Cu 3 O 7-δ system is discussed. 26 refs.; 6 figs.; 1 tab

  14. Comprensión lectora : prácticas de Psicología

    OpenAIRE

    Manuel de los Bueis, José Manuel

    2011-01-01

    Prácticas en la especialidad de Psicología de la educación, realizadas en gabinete privado. Taller de comprensión lectora. Se describen algunas tareas llevadas a cabo en las prácticas: entrevistas, taller de comprensión lectora, evaluación, supervisión. Pràctiques en l'especialitat de Psicologia de l'educació, realitzades en gabinet privat. Taller de comprensió lectora. Es descriuen algunes tasques portades a terme en les pràctiques: entrevistes, taller de comprensió lectora, avaluació, su...

  15. Phase equilibria of the Al-Pr-Zr ternary system at 773 K

    Energy Technology Data Exchange (ETDEWEB)

    She, Jia [Laboratory of Nonferrous Metal Materials and New Processing Technology, Ministry of Education, Guangxi University, Nanning, Guangxi 530004 (China); Zhan, Yongzhong, E-mail: zyzmatres@yahoo.com.c [Laboratory of Nonferrous Metal Materials and New Processing Technology, Ministry of Education, Guangxi University, Nanning, Guangxi 530004 (China); Li, Chunliu [Laboratory of Nonferrous Metal Materials and New Processing Technology, Ministry of Education, Guangxi University, Nanning, Guangxi 530004 (China); Du, Yong; Xu, Honghui; He, Yuehui [State Key Laboratory of Powder Metallurgy, Central South University, Changsha, Hunan 410083 (China)

    2010-07-30

    The phase equilibria of the Al-Pr-Zr ternary system at 773 K have been investigated mainly by means of X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and differential thermal analysis (DTA). The 14 binary compounds, i.e. AlZr{sub 3}, AlZr{sub 2}, Al{sub 2}Zr{sub 3}, Al{sub 3}Zr{sub 4}, AlZr, Al{sub 3}Zr{sub 2}, Al{sub 2}Zr, Al{sub 3}Zr, {alpha}-Al{sub 11}Pr{sub 3}, Al{sub 3}Pr, Al{sub 2}Pr, {beta}-AlPr, AlPr{sub 2} and {beta}-AlPr{sub 3} were confirmed. No binary compound was found in the Pr-Zr binary system. The result shows that the isothermal section of the Al-Pr-Zr ternary system at 773 K consists of 17 single-phase regions, 31 two-phase regions and 15 three-phase regions. All the intermediate compounds phases in this system have not a remarkable solid solution at 773 K. No ternary compound is found in this work.

  16. Phase equilibria of the Al-Pr-Zr ternary system at 773 K

    International Nuclear Information System (INIS)

    She, Jia; Zhan, Yongzhong; Li, Chunliu; Du, Yong; Xu, Honghui; He, Yuehui

    2010-01-01

    The phase equilibria of the Al-Pr-Zr ternary system at 773 K have been investigated mainly by means of X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and differential thermal analysis (DTA). The 14 binary compounds, i.e. AlZr 3 , AlZr 2 , Al 2 Zr 3 , Al 3 Zr 4 , AlZr, Al 3 Zr 2 , Al 2 Zr, Al 3 Zr, α-Al 11 Pr 3 , Al 3 Pr, Al 2 Pr, β-AlPr, AlPr 2 and β-AlPr 3 were confirmed. No binary compound was found in the Pr-Zr binary system. The result shows that the isothermal section of the Al-Pr-Zr ternary system at 773 K consists of 17 single-phase regions, 31 two-phase regions and 15 three-phase regions. All the intermediate compounds phases in this system have not a remarkable solid solution at 773 K. No ternary compound is found in this work.

  17. Energy transfer in LaF3: R3+, Pr3+ (where R = Nd, Dy)

    International Nuclear Information System (INIS)

    Reddy, B.R.; Venkateswarlu, P.

    1982-01-01

    Fluorescence is observed for 1 D 2 levels of Pr 3+ on exciting the higher lying level 3 P 0 in doubly doped systems LaF 3 : R 3+ , Pr 3+ (R = Nd or Dy) but not in LaF 3 :Pr 3+ . From the recorded excitation spectra, and the measured decay times, it has been found that the drain mechanism of population to 1 D 2 levels is caused in doubly doped systems by ion-pair relaxation between Pr 3+ ( 3 P 0 -- 1 D 2 ) and Nd 3+ (Z-X) or Dy 3+ (Z-Y) ions

  18. Pressure dependence of crystal field splitting in Pr pnictides and chalcogenides

    International Nuclear Information System (INIS)

    Schirber, J.E.; Weaver, H.T.; Ginley, D.S.

    1978-01-01

    We have measured the pressure dependence of the Pr nuclear magnetic resonance shift in PrN, PrP, PrSb, PrAs, PrS and PrSe. The shifts in all the pnictides increase while in the chalcogenides the shifts decrease with pressure. The rare earth frequency shift is inversely proportional to the crystal field splitting in the context of the point charge model (PCM) so a decrease would be expected for all of these materials at a rate of 5/3 the volume compressibility. Our values for the pnictides tend to be considerably larger than the PCM value as well as the wrong sign. The chalcogenide values are much nearer in magnitude and are of the right sign for the PCM. Contrary to the report of Guertin et al. we see no anomaly in the pressure dependence of the susceptibility of PrS. The fact that PrN which is reported to be non-metallic also shows the wrong sign for the PCM presents difficulties for various conduction electron explanations for this unexpected behavior of the pnictides

  19. PrPC has nucleic acid chaperoning properties similar to the nucleocapsid protein of HIV-1.

    Science.gov (United States)

    Derrington, Edmund; Gabus, Caroline; Leblanc, Pascal; Chnaidermann, Jonas; Grave, Linda; Dormont, Dominique; Swietnicki, Wieslaw; Morillas, Manuel; Marck, Daniel; Nandi, Pradip; Darlix, Jean-Luc

    2002-01-01

    The function of the cellular prion protein (PrPC) remains obscure. Studies suggest that PrPC functions in several processes including signal transduction and Cu2+ metabolism. PrPC has also been established to bind nucleic acids. Therefore we investigated the properties of PrPC as a putative nucleic acid chaperone. Surprisingly, PrPC possesses all the nucleic acid chaperoning properties previously specific to retroviral nucleocapsid proteins. PrPC appears to be a molecular mimic of NCP7, the nucleocapsid protein of HIV-1. Thus PrPC, like NCP7, chaperones the annealing of tRNA(Lys) to the HIV-1 primer binding site, the initial step of retrovirus replication. PrPC also chaperones the two DNA strand transfers required for production of a complete proviral DNA with LTRs. Concerning the functions of NCP7 during budding, PrPC also mimices NCP7 by dimerizing the HIV-1 genomic RNA. These data are unprecedented because, although many cellular proteins have been identified as nucleic acid chaperones, none have the properties of retroviral nucleocapsid proteins.

  20. 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.

  1. Crystal growth and luminescence properties of Pr-doped LuLiF4 single crystal

    International Nuclear Information System (INIS)

    Sugiyama, Makoto; Yanagida, Takayuki; Yokota, Yuui; Kurosawa, Shunsuke; Fujimoto, Yutaka; Yoshikawa, Akira

    2013-01-01

    0.1, 1, and 3% Pr (with respect to Lu) doped LuLiF 4 (Pr:LuLiF 4 ) single crystals were grown by the micro-pulling-down (μ-PD) method. Transparency of the grown crystals was higher than 70% in the visible wavelength region with some absorption bands due to Pr 3+ 4f-4f transitions. Intense absorption bands related with the Pr 3+ 4f-5d transitions were observed at 190 and 215 nm. In radioluminescence spectra, Pr 3+ 5d-4f emissions were observed at 220, 240, 340, and 405 nm. In the pulse height spectra recorded under 137 Cs γ-ray excitation, the Pr 3% doped sample showed the highest light yield of 2050 photons/MeV and the scintillation decay time of it exhibited 23 and 72 ns also excited by 137 Cs γ-ray. -- Highlights: ► 0.1, 1, and 3% Pr-doped LuLiF 4 single crystals were grown by the μ-PD method. ► Pr 3+ 5d-4f emission peaks appeared at 220, 240, 340, and 405 nm ► The Pr 3%:LuLiF 4 crystal showed the highest light yield of 2050 photons/MeV

  2. Comparison of the luminescent properties of Lu3Al5O12:Pr crystals and films under synchrotron radiation excitation

    International Nuclear Information System (INIS)

    Zorenko, Yu.; Gorbenko, V.; Zorenko, T.; Voznyak, T.; Nizankovskiy, S.

    2016-01-01

    The work is dedicated to comparative investigation of the luminescent properties of Lu 3 Al 5 O 12 :Pr(LuAG:Pr) single crystals and single crystalline films using excitation by synchrotron radiation with an energy of 3.7–25 eV in the exciton range of LuAG host. We have found that the differences in the excitation spectra and luminescence decay kinetics of LuAG:Pr crystals and films are caused by involving the LuAl antisite defects and oxygen vacancies in the crystals and Pb 2+ flux related dopants in the films in the excitation processes of the Pr 3+ luminescence. Taking into account these differences, we have determined the energy structure of the Pr 3+ ions in LuAG host and estimated the differences in the energies of creation of excitons bound with the isolated Pr 3+ ions in LuAG:Pr films and the dipole Pr–LuAl antisite defect centers in the crystal counterpart. - Highlights: • Comparison of the luminescent properties of LuAG:Pr single crystals and films. • Superposition of the Pr 3+ and defect centers luminescence of LuAG:Pr crystal. • Different creation energies of an excitons bound with the Pr 3+ in LuAG:Pr crystals and films. • More faster decay kinetics of the Pr 3+ luminescence in LuAG:Pr films. • Low content of slow emission component in LuAG:Pr films.

  3. A prática da Docência no Curso de Jornalismo da Unicentro/Guarapuava-PR

    Directory of Open Access Journals (Sweden)

    Wanda Terezinha Pacheco dos Santos

    2016-04-01

    Full Text Available O presente artigo é resultado de uma pesquisa realizada com professores do curso de Jornalismo da Universidade Estadual do Centro-Oeste – Unicentro – Guarapuava- PR em que o objetivo foi investigar a importância da formação pedagógica do docente, uma vez que o curso forma profissionais bacharéis e que não possuem conteúdos pedagógicos em sua estrutura curricular. Na fundamentação deste trabalho, foram estudados autores que pesquisam tanto sobre jornalismo quanto docência universitária como Andrade e Linhares, Masetto, Anastasiou, Nóvoa, Marcelo, entre outros. Para coleta dos dados, foi encaminhado via e-mail um questionário aos professores do curso de Jornalismo da Unicentro com seis perguntas abertas. A análise levou em conta quatro questionários respondidos. Diante dos relatos, para os entrevistados a formação pedagógica faz todo diferencial em sala de aula, no entanto nem todos, mesmo reconhecendo a importância da formação docente, se interessam em melhorar sua prática. Nesse sentido, para que essa formação seja consolidada é importante o desenvolvimento de ações institucionais, a partir de um projeto de formação continuada organizado, sistemático e intencional e que envolva todos os professores universitários.

  4. 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)

  5. Effects of FlAsH/Tetracysteine (TC) tag on PrP proteolysis and PrPres formation by TC-scanning

    Science.gov (United States)

    Taguchi, Yuzuru; Hohsfield, Lindsay A.; Hollister, Jason R.

    2014-01-01

    The FlAsH/tetracysteine (FlAsH/TC) tag is a powerful tool for fluorescent labeling of proteins. However, even small tags such as FlAsH/TC could alter the behavior of the tagged proteins, especially if the insertion occurs at internal sites. Defining the influence of FlAsH/TC on nearby protein-protein interactions might aid in selecting appropriate positions for internal TC insertions and allow the exploitation of serial FlAsH/TC insertions (TC-scanning) as a probe to characterize sites of protein-protein interaction. To explore this application in the context of substrate-protease interactions, we analyzed the effect of FlAsH/TC insertions on proteolysis of cellular prion protein (PrPsen) in in vitro reactions and generation of the C1 metabolic fragment of PrPsen in live neuroblastoma cells. The influence of FlAsH/TC insertion was evaluated by TC-scanning across the cleavage sites of each protease. The results showed that FlAsH/TC inhibited protease cleavage only within limited ranges of the cleavage sites that varied from about 1 to 6 residues-wide depending on the protease, providing an estimate of the PrP residues interacting with each protease. TC-scanning was also used to probe a different type of protein-protein interaction, the conformational conversion of FlAsH-PrPsen to the prion disease-associated isoform, PrPres. PrP constructs with FlAsH/TC insertions at residues 90–96 but not 97–101 were converted to FlAsH-PrPres, identifying a boundary separating loosely versus compactly folded regions of PrPres. Our observations demonstrate that TC-scanning with the FlAsH/TC tag can be a versatile method for probing protein-protein interactions and folding processes. PMID:23943295

  6. Singlet ground-state fluctuations in praseodymium observed by muon spin relaxation in PrP and PrP0.9

    International Nuclear Information System (INIS)

    Noakes, D R; Waeppling, R; Kalvius, G M; Jr, M F White; Stronach, C E

    2005-01-01

    Muon spin relaxation (μSR) in the singlet ground-state compounds PrP and PrP 0.9 reveals the unusual situation of a Lorentzian local field distribution with fast-fluctuation-limit strong-collision dynamics, a case that does not show motional narrowing. Contrary to publications by others, where PrP 0.9 was asserted to have vacancy-induced spin-glass freezing, no spin-glass freezing is seen in PrP 0.9 or PrP down to ≤100mK. This was confirmed by magnetization measurements on these same samples. In both compounds, the muon spin relaxation rate does increase as temperature decreases, demonstrating increasing strength of the paramagnetic response. A Monte Carlo model of fluctuations of Pr ions out of their crystalline-electric-field singlet ground states into their magnetic excited states (and back down again) produces the strong-collision-dynamic Lorentzian relaxation functions observed at each individual temperature but not the observed temperature dependence. This model contains no exchange interaction, and so predicts decreasing paramagnetic response as the temperature decreases, contrary to the temperature dependence observed. Comparison of the simulations to the data suggests that the exchange interaction is causing the system to approach magnetic freezing (by mode softening), but fails to complete the process

  7. 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.

  8. 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

  9. 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

  10. A Teledermatologia na Prática Médica

    Directory of Open Access Journals (Sweden)

    Samira Yarak

    Full Text Available RESUMO Fundamentos As doenças da pele são causas comuns da procura de atendimento na atenção primária em saúde, e a maioria desses atendimentos é realizada por médicos não dermatologistas. Em geral, o aprendizado insuficiente na graduação se reflete na atuação clínica e, consequentemente, em atendimentos referenciados, resultando em aumento de custo. Teledermatologia é a prática da dermatologia com uso de tecnologias de informação e sistemas de comunicação para a troca de informações médicas de um paciente entre médico não dermatologista e um dermatologista (teledermatologia secundária – nos mesmos ou em diferentes momentos e em diferentes localizações geográficas. A teledermatologia secundária promete ser melhor, mais barata e mais rápida, embora as evidências não sejam suficientes em relação ao curso clínico da doença. Objetivo Revisar a literatura sobre as evidências científicas da teledermatologia secundária na prática médica. Método Revisão da literatura, entre 1999 e 2014, de ensaios clínicos, estudos observacionais, revisões e revisões sistemáticas identificados no PubMed sobre a teledermatologia secundária na prática médica. Além desses estudos, foram incluídos ensaios clínicos mais recentes realizados no Brasil sobre acurácia ou concordância de diagnóstico da teledermatologia secundária da base bibliográfica Lilacs durante o mesmo período e outros estudos relevantes de outras bases em relação à educação médica e dados demográficos. Resultados Foram incluídos 11 estudos mais recentes e/ou relevantes quanto à amostra e ao padrão clínico de diagnóstico. O resultado desta revisão foi dividido em quatro tópicos: eficiência da teledermatologia na atenção primária em saúde; acurácia concordância ou confiabilidade do diagnóstico da teledermatologia na atenção primária em saúde em relação à consulta presencial; satisfação e qualidade de vida do paciente

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

    Indian Academy of Sciences (India)

    in Pr content, the crystal structures of BPGFO thin films retain rhombohedral (R3c) symmetry accompanied by structure distortion. ... Pr and Gd co-modified BiFeO3 thin film; ferroelectric properties; sol-gel. 1. Introduction. In recent years, great attention has been paid to single- phase BiFeO3 (BFO) multiferroic materials ...

  12. Evolution of structural, magnetic and transport behavior by Pr doping in SrRuO3

    Science.gov (United States)

    Gupta, Renu; Pramanik, A. K.

    2018-05-01

    Here we report the evolution of structural, magnetic and transport behavior in perovskite based ruthenates Sr1-xPrxRuO3 (x=0.0 and 0.1). The substitution of Pr on Sr site retains orthorhombic structure while we find the slight change in structural parameters. The SrRuO3 has itinerant ferromagnet (FM) type nature of ordering temperature ˜160 K and below the transition temperature showing large bifurcation between ZFC and FC magnetization. By Pr doping, the magnetic moment decreases with decreasing bifurcation of ZFC and FC. The ZFC data show three distinct peaks (three transition temperature; TM1,TM2 and TM3). The magnetization study of both the samples, at high temperature fitted with modified CWL showing the decreasing value of ordering temperature by Pr doping matches close to TM2. The low-temperature isothermal magnetization M (H) data show that the high field saturation moment has decreased by Pr doping. The Arrott plot gives spontaneous magnetization (Ms) which is also decreased by Pr substitution. Evolution of Rhodes-Wohlfarth ratio value increases, which suggests that FM in this system evolves toward the more itinerant type by Pr doping. The electrical resistivity ρ(T) of both the samples show metallic behavior, in the all temperature range and ρ(T) increases by Pr doping while around below 45 K, the resistivity decreases by Pr doping and this crossing temperature also matches with ZFC data.

  13. Hydrogen-induced electrical and optical switching in Pd capped Pr ...

    Indian Academy of Sciences (India)

    Wintec

    Abstract. In this study, modification in the properties of hydrogen-induced switchable mirror based on Pr nanoparticle layers is reported. The reversible changes in hydrogen-induced electrical and optical properties of Pd capped Pr nanoparticle layers have been studied as a function of hydrogenation time and compared.

  14. Polymorphisms at Amino Acid Residues 141 and 154 Influence Conformational Variation in Ovine PrP

    Science.gov (United States)

    Yang, Sujeong; Thackray, Alana M.; Hopkins, Lee; Monie, Tom P.; Burke, David F.; Bujdoso, Raymond

    2014-01-01

    Polymorphisms in ovine PrP at amino acid residues 141 and 154 are associated with susceptibility to ovine prion disease: Leu141Arg154 with classical scrapie and Phe141Arg154 and Leu141His154 with atypical scrapie. Classical scrapie is naturally transmissible between sheep, whereas this may not be the case with atypical scrapie. Critical amino acid residues will determine the range or stability of structural changes within the ovine prion protein or its functional interaction with potential cofactors, during conversion of PrPC to PrPSc in these different forms of scrapie disease. Here we computationally identified that regions of ovine PrP, including those near amino acid residues 141 and 154, displayed more conservation than expected based on local structural environment. Molecular dynamics simulations showed these conserved regions of ovine PrP displayed genotypic differences in conformational repertoire and amino acid side-chain interactions. Significantly, Leu141Arg154 PrP adopted an extended beta sheet arrangement in the N-terminal palindromic region more frequently than the Phe141Arg154 and Leu141His154 variants. We supported these computational observations experimentally using circular dichroism spectroscopy and immunobiochemical studies on ovine recombinant PrP. Collectively, our observations show amino acid residues 141 and 154 influence secondary structure and conformational change in ovine PrP that may correlate with different forms of scrapie. PMID:25126555

  15. Epidemiology of Chronic Wasting Disease: PrP(res) Detection, Shedding, and Environmental Contamination

    National Research Council Canada - National Science Library

    Williams, Elizabeth S; Miller, Michael W; Lewis, Randolf V; Raisbeck, Merl F; Cook, Walter W

    2004-01-01

    .... The specific goals of these studies are to develop sensitive as says for PrP(exp res) as a marker for infectivity, and use these techniques to monitor the dynamics and modes of shedding of PrP(exp res...

  16. Casos prácticos Salud Pública para estudiantes de Trabajo Social

    OpenAIRE

    Vives Cases, Carmen; Davó Blanes, María del Carmen; Gil González, Diana

    2008-01-01

    Aprendizaje práctico de los temas relacionados con los determinantes de la salud y de las desigualdades en salud, promoción de la salud, planificación en salud y diagnóstico de la situación de salud de una comunidad mediante la resolución de casos prácticos.

  17. 33 CFR 110.74c - Bahia de San Juan, PR.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Bahia de San Juan, PR. 110.74c Section 110.74c Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY ANCHORAGES ANCHORAGE REGULATIONS Special Anchorage Areas § 110.74c Bahia de San Juan, PR. The waters of San Antonio...

  18. PR-etenduse osatäitjad / Kadri Bank, Kadri Jakobson

    Index Scriptorium Estoniae

    Bank, Kadri

    2011-01-01

    Käsimüügiravimite vabaturule lubamise temaatika on ravimitootjate ja apteegikettide omanike vahel käivitanud PR-sõja. Ravimitootjate Liidu PR-kampaania avaürituseks oli käsimüügiravimite vabamüüki lubamise uuringu esitlus

  19. Synthesis and thermoluminescence of LaAlO3:Pr3+ to UVC radiation dosimetry

    International Nuclear Information System (INIS)

    Morales-Hernández, A.; Zarate-Medina, J.; Contreras-García, M.E.; Azorín-Nieto, J.; Rivera-Montalvo, T.

    2016-01-01

    Thermoluminescent (TL) response of trivalent praseodymium ion doped lanthanum aluminate (LaAlO 3 :Pr 3+ ) obtained by Pechini method and Spray Dryer was studied. TL response of LaAlO 3 :Pr 3+ powders submitted at 1600 °C exhibited one peak centered at 157 °C. Sensitivity of LaAlO 3 :Pr 3+ was improved in around 90 times compared with undoped LaAlO 3 . TL response as a function of wavelength showed a maximum in 230 nm. Dosimetric characteristics of LaAlO 3 :Pr 3+ under UVR radiation effects were analyzed. Evaluation of activation energy was obtained by Glow Fit v.1.3 software. Experimental results about thermoluminescent characteristics of LaAlO 3 :Pr 3+ suggest as good candidate to be employed as a complementary thermoluminescent device with other TL phosphors as aluminum oxide - Highlights: • High sensitivity of new phosphor to UVC dosimetry was is studied. • Thermoluminescence response of LaAlO 3 :Pr 3+ is presented. • LaAlO 3 :Pr 3+ is suggested as UVCR dosimeter. • TL response of LaAlO 3 :Pr 3+ has dependence on sintering temperature.

  20. First Principles Calculation of the Damping and Quasielastic Mode of DHCP-Pr

    DEFF Research Database (Denmark)

    Yang, D.; Lindgård, Per-Anker

    1979-01-01

    Starting with the interaction between the conduction and 4f electrons and taking the single-ion levels of Pr to be a singlet and a doublet, we have derived the dynamical susceptibility for dhcp Pr with Mori's memory function formalism [1]. The dynamics of the electron hole relaxation reflects...

  1. 33 CFR 165.754 - Safety Zone: San Juan Harbor, San Juan, PR.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Safety Zone: San Juan Harbor, San Juan, PR. 165.754 Section 165.754 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND... Zone: San Juan Harbor, San Juan, PR. (a) Regulated area. A moving safety zone is established in the...

  2. Single-Phase 3L PR Controlled qZS Inverter Connected to the Distorted Grid

    DEFF Research Database (Denmark)

    Makovenko, Elena; Husev, Oleksandr; Roncero-Clemente, Carlos

    2016-01-01

    This paper presents a single-phase three-level NPC qZS inverter connected to a distorted grid using PID and PR regulators. A case study system along with the control strategy are described. Tuning approaches for PID and PR regulators are addressed and validated by means of simulation results...

  3. μ+ relaxation correlated with susceptibility in the van-Vleck paramagnet PrIn3

    International Nuclear Information System (INIS)

    Grayevsky, A.; Amato, A.; Pinkpank, M.; Schenck, A.

    1997-01-01

    A previously unobserved increase of the magnetic susceptibility in PrIn 3 at low temperatures is reported. The increase is shown to correlate nicely with a large increase in the transverse μSR depolarization rate. Evidence supports the conclusion that both phenomena are related to some degree of atomic disorder in the structure, and an associated strong Pr CEF level changes. (orig.)

  4. Diversity of PR3-ANCA epitope specificity in Wegener's granulomatosis. Analysis using the biosensor technology

    NARCIS (Netherlands)

    Rarok, Agnieszka; van der Geld, Y.M.; Stegeman, Coen; Limburg, Piet; Kallenberg, Cees

    Wegener's granulomatosis is a systemic disease characterized by the presence of antineutrophil cytoplasm autoantibodies specific for proteinase 3 (PR3-ANCA). The functional characteristics of PR3-ANCA differ between quiescent and active disease, suggesting changes in the properties of the

  5. EI/DSD : ejercicio práctico 1, febrero 2013

    OpenAIRE

    Universitat Oberta de Catalunya

    2013-01-01

    Exercici pràctic 1 (EP1)d'estructura de la informació, disseny d'estructures de dades. Ejercicio práctico 1 (EP1) de estructura de la información, diseño de estructuras de datos. Exercise 1 (EP1) about information structure, data structure design.

  6. EI/DSD : exercici pràctic 1, febrer 2013

    OpenAIRE

    Blasco Planesas, Jordi

    2013-01-01

    Exercici pràctic 1 (EP1)d'estructura de la informació, disseny d'estructures de dades. Ejercicio práctico 1 (EP1) de estructura de la información, diseño de estructuras de datos. Exercise 1 (EP1) about information structure, data structure design.

  7. 76 FR 34296 - Proposed Collection; Comment Request for Forms 1040-PR and 1040-SS

    Science.gov (United States)

    2011-06-13

    ... Form 1040-PR, Planilla para la Declaraci[oacute]n de la Contribuci[oacute]n Federal sobre el Trabajo... Trabajo por Cuenta Propia (Incluyendo el Cr[eacute]dito Tributario Adicional por Hijos para Residentes... Subtitle A, and provide credit to the taxpayer's social security account. Anejo H-PR is used to compute...

  8. 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...

  9. Herramientas digitales de trabajo colaborativo para comunidades de práctica

    OpenAIRE

    Rodera Bermúdez, Ana María

    2012-01-01

    Manual recopilatorio de servicios de la web 2.0 susceptibles de ser utilizados en comunidades de práctica. Manual recopilatori de serveis de la web 2.0 susceptibles de ser utilitzats en comunitats de pràctica. Manual compilation of web 2.0 services that can be used in communities of practice.

  10. Suured prügifirmad püüavad Saaremaa turgu / Mehis Tulk

    Index Scriptorium Estoniae

    Tulk, Mehis, 1967-

    2004-01-01

    Eelseisvate jäätmeveokonkursside tarvis on Saare maakonnas jäätmeloa hankinud lisaks OÜ-le Prügimees ka suured välismaised firmad Ragn-Sells ja Cleanaway. Tabel: Andmed jäätmekäitlusfirmade OÜ Prügimees, Cleanaway, Ragn Sells kohta. Vt. samas: Luba igal juhul vajalik

  11. The insectivorous sundew (Drosera rotundifolia, L.) might be a novel source of PR genes for biotechnology

    NARCIS (Netherlands)

    Matusikova, I.; Libantova, J.; Moravcikova, J.; Mlynarova, L.; Nap, J.P.H.

    2004-01-01

    The gene pool of insectivorous sundew, Drosera rotundifolia L., was studied to identify and analyse sequences encoding for pathogenesis-related (PR) proteins. The digested genomic DNA was in ¿inverted¿ Southern hybridisation probed to 19 clones for PR genes from different plant sources. From

  12. 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...

  13. Práctica 1. Introducción a las redes de computadores

    OpenAIRE

    Pomares Baeza, Jorge; Candelas Herías, Francisco Andrés

    2009-01-01

    Práctica primera de la asignatura que pretende introducir al alumno en las redes de computadores de forma práctica. Para ello se analizará el estudio de una Red de Área Local (LAN) que emplea la arquitectura de red TCP/IP.

  14. TRMM/LIS and PR Observations and Thunderstorm Activity

    Science.gov (United States)

    Ohita, S.; Morimoto, T.; Kawasaki, Z. I.; Ushio, T.

    2005-12-01

    Thunderstorms observed by TRMM/PR and LIS have been investigating, and Lightning Research Group of Osaka University (LRG-OU) has unveiled several interesting features. Correlation between lightning activities and the snow depth of convective clouds may follow the power-five law. The power five law means that the flash density is a function of the snow-depth to power five. The definition of snow depth is the height of detectable cloud tops by TRMM/PR from the climatological freezing level, and it may be equivalent to the length of the portion where the solid phase precipitation particles exist. This is given by examining more than one million convective clouds, and we conclude that the power five law should be universal from the aspect of the statistic. Three thunderstorm active areas are well known as "Three World Chimneys", and those are the Central Africa, Amazon of the South America, and South East Asia. Thunderstorm activities in these areas are expected to contribute to the distribution of thermal energy around the equator to middle latitude regions. Moreover thunderstorm activity in the tropical region is believed to be related with the average temperature of our planet earth. That is why long term monitoring of lightning activity is required. After launching TRMM we have accumulated seven-year LIS observations, and statistics for three world chimneys are obtained. We have recognized the additional lightning active area, and that is around the Maracaibo lake in Venezuera. We conclude that this is because of geographical features of the Maracaibo lake and the continuous easterly trade wind. Lightning Activity during El Niño period is another interesting subject. LRGOU studies thunderstorm occurrences over west Indonesia and south China, and investigates the influence of El Nino on lightning . We compare the statistics between El Nino and non El Nino periods. We learn that the lightning activity during El Niño period is higher than non El Nino period instead

  15. Unraveling Prion Protein Interactions with Aptamers and Other PrP-Binding Nucleic Acids.

    Science.gov (United States)

    Macedo, Bruno; Cordeiro, Yraima

    2017-05-17

    Transmissible spongiform encephalopathies (TSEs) are a group of neurodegenerative disorders that affect humans and other mammals. The etiologic agents common to these diseases are misfolded conformations of the prion protein (PrP). The molecular mechanisms that trigger the structural conversion of the normal cellular PrP (PrP C ) into the pathogenic conformer (PrP Sc ) are still poorly understood. It is proposed that a molecular cofactor would act as a catalyst, lowering the activation energy of the conversion process, therefore favoring the transition of PrP C to PrP Sc . Several in vitro studies have described physical interactions between PrP and different classes of molecules, which might play a role in either PrP physiology or pathology. Among these molecules, nucleic acids (NAs) are highlighted as potential PrP molecular partners. In this context, the SELEX (Systematic Evolution of Ligands by Exponential Enrichment) methodology has proven extremely valuable to investigate PrP-NA interactions, due to its ability to select small nucleic acids, also termed aptamers, that bind PrP with high affinity and specificity. Aptamers are single-stranded DNA or RNA oligonucleotides that can be folded into a wide range of structures (from harpins to G-quadruplexes). They are selected from a nucleic acid pool containing a large number (10 14 -10 16 ) of random sequences of the same size (~20-100 bases). Aptamers stand out because of their potential ability to bind with different affinities to distinct conformations of the same protein target. Therefore, the identification of high-affinity and selective PrP ligands may aid the development of new therapies and diagnostic tools for TSEs. This review will focus on the selection of aptamers targeted against either full-length or truncated forms of PrP, discussing the implications that result from interactions of PrP with NAs, and their potential advances in the studies of prions. We will also provide a critical evaluation

  16. Assessment of the PrPc Amino-Terminal Domain in Prion Species Barriers.

    Science.gov (United States)

    Davenport, Kristen A; Henderson, Davin M; Mathiason, Candace K; Hoover, Edward A

    2016-12-01

    Chronic wasting disease (CWD) in cervids and bovine spongiform encephalopathy (BSE) in cattle are prion diseases that are caused by the same protein-misfolding mechanism, but they appear to pose different risks to humans. We are interested in understanding the differences between the species barriers of CWD and BSE. We used real-time, quaking-induced conversion (RT-QuIC) to model the central molecular event in prion disease, the templated misfolding of the normal prion protein, PrP c , to a pathogenic, amyloid isoform, scrapie prion protein, PrP Sc We examined the role of the PrP c amino-terminal domain (N-terminal domain [NTD], amino acids [aa] 23 to 90) in cross-species conversion by comparing the conversion efficiency of various prion seeds in either full-length (aa 23 to 231) or truncated (aa 90 to 231) PrP c We demonstrate that the presence of white-tailed deer and bovine NTDs hindered seeded conversion of PrP c , but human and bank vole NTDs did the opposite. Additionally, full-length human and bank vole PrP c s were more likely to be converted to amyloid by CWD prions than were their truncated forms. A chimera with replacement of the human NTD by the bovine NTD resembled human PrP c The requirement for an NTD, but not for the specific human sequence, suggests that the NTD interacts with other regions of the human PrP c to increase promiscuity. These data contribute to the evidence that, in addition to primary sequence, prion species barriers are controlled by interactions of the substrate NTD with the rest of the substrate PrP c molecule. We demonstrate that the amino-terminal domain of the normal prion protein, PrP c , hinders seeded conversion of bovine and white-tailed deer PrP c s to the prion forms, but it facilitates conversion of the human and bank vole PrP c s to the prion forms. Additionally, we demonstrate that the amino-terminal domain of human and bank vole PrP c s requires interaction with the rest of the molecule to facilitate conversion by CWD

  17. Inelastic neutron scattering study of crystal field levels in PrOs4As12

    International Nuclear Information System (INIS)

    Chi, Songxue; Dai, Pengcheng; Barnes, T.F.E.; Kang, H. J.; Lynn, J. W.; Ye, Feng; Maple, M. B.

    2008-01-01

    We use neutron scattering to study the Pr 3+ crystalline electric field (CEF) excitations in the filled skutterudite PrOs 4 As 12 . By comparing the observed levels and their strengths under neutron excitation with the theoretical spectrum and neutron excitation intensities, we identify the Pr 3+ CEF levels, and show that the ground state is a magnetic Γ 4 (2) triplet, and the excited states Γ 1 , Γ 4 (1) and Γ 23 are at 0.4, 13 and 23 meV, respectively. A comparison of the observed CEF levels in PrOs 4 As 12 with the heavy fermion superconductor PrOs 4 Sb 12 reveals the microscopic origin of the differences in the ground states of these two filled skutterudites

  18. The influence on intrinsic light emission of calcium tungstate and molybdate powders by multivalence Pr codoping

    International Nuclear Information System (INIS)

    Zhu, Fang; Xiao, Zhisong; Yan, Lu; Zhang, Feng; Huang, Anping

    2010-01-01

    For trivalent praseodymium (Pr 3+ ) and quadrivalent praseodymium (Pr 4+ ) codoped CaMO 4 (M = W, Mo) powders, the luminescence propriety of matrix is obviously influenced by carrier concentration. The light emission intensity of CaWO 4 matrix decreases exponentially with increasing of Pr concentration because oxygen-deficient (WO 3 .V O ) obtains an electron supplied by Pr 3+ (5d). However, the light emission intensity of CaMoO 4 is enhanced by Pr codoping because the quasi-free electrons increase the probability of radiative combination. The difference of photoluminescence properties in the two materials are attributed to the bonding character of M and O in the CaMO 4 structure. (orig.)

  19. Local distortion induced metal-to-insulator phase transition in PrRu4P12

    International Nuclear Information System (INIS)

    Cao, D.; Heffner, R.H.; Jeong, I.-K.; Bauer, E.D.; Bridges, F.; Yuhasz, W.M.; Maple, M.B.

    2005-01-01

    Extended x-ray absorption fine structure (EXAFS) experiments have been carried out on PrRu 4 P 12 and PrOs 4 P 12 to study the metal-to-insulator (MI) phase transition in PrRu 4 P 12 . No Pr displacement was observed across the MI transition temperature from the EXAFS data. Instead, our EXAFS data clearly show that a Ru displacement is associated with this MI transition. The very high Debye temperature for the Ru-P bond (Θ D =690 K) suggests that a slight rotation/displacement of relatively rigid RuP 6 octahedra leads to this small Ru displacement, which accompanies the MI transition at 62 K in PrRu 4 P 12

  20. Instability of Yb3+ and Pr3+ low-symmetry luminescence centers in gallium phosphide

    International Nuclear Information System (INIS)

    Kasatkin, V.A.

    1985-01-01

    The stability of γb 3+ and Pr 3+ low-symmetry luminescence centers formed in gallium phosphide during quenching were studied in the process of durable storage and annealing. Observation of the Yb 3+ and Pr 3+ centrer states was accomplished by the photoluminescence spectra at 18 K. It has been established that annealing in the dark under normal conditions results in a reduced integral luminescence intensity of all low-symmetry Yb 3+ and Pr 3+ centers. Annealing of quenched GaP and GaP saples at 400 K results in complete disappearance of intracenter luminescence of Pr 3+ and low-symmetry Yb 3+ centers. Decomposition during storage and low anealing temperature point to the instability of low-symmetry centers of Pr 3+ and Yb 3+ luminescence

  1. Role of PR-Interval In Predicting the Occurrence of Atrial Fibrillation

    DEFF Research Database (Denmark)

    Bidstrup, Signe Brøker; Salling Olesen, Morten; Hastrup Svendsen, Jesper

    2013-01-01

    The identification of individuals at high risk of developing atrial fibrillation (AF) is important to prevent potentially lethal and invalidating complications of this arrhythmia. Recently, several studies have investigated the association between PR-interval and the risk of AF and have tested...... the value of PR-interval in personalized risk scores for AF. However, the results of these studies are generally conflicting. When looking for an association between a prolonged PR-interval (first-degree atrioventricular [AV] block vs. normal PR-interval) and an increased risk of AF, not all studies were...... able to find a consistent and statistically significant association. In two recent studies, however, the investigators were able to show an increased risk of AF for individuals with PR-intervals in the short range compared with individuals in the middle range. The existence of a true U...

  2. PR Toxin – Biosynthesis, Genetic Regulation, Toxicological Potential, Prevention and Control Measures: Overview and Challenges

    Directory of Open Access Journals (Sweden)

    Manish K. Dubey

    2018-03-01

    Full Text Available Out of the various mycotoxigenic food and feed contaminant, the fungal species belonging to Penicillium genera, particularly Penicillium roqueforti is of great economic importance, and well known for its crucial role in the manufacturing of Roquefort and Gorgonzola cheese. The mycotoxicosis effect of this mold is due to secretion of several metabolites, of which PR toxin is of considerable importance, with regard to food quality and safety challenges issues. The food products and silages enriched with PR toxin could lead into damage to vital internal organs, gastrointestinal perturbations, carcinogenicity, immunotoxicity, necrosis, and enzyme inhibition. Moreover, it also has the significant mutagenic potential to disrupt/alter the crucial processes like DNA replication, transcription, and translation at the molecular level. The high genetic diversities in between the various strains of P. roqueforti persuaded their nominations with Protected Geographical Indication (PGI, accordingly to the cheese type, they have been employed. Recently, the biosynthetic mechanism and toxicogenetic studies unraveled the role of ari1 and prx gene clusters that cross-talk with the synthesis of other metabolites or involve other cross-regulatory pathways to negatively regulate/inhibit the other biosynthetic route targeted for production of a strain-specific metabolites. Interestingly, the chemical conversion that imparts toxic properties to PR toxin is the substitution/oxidation of functional hydroxyl group (-OH to aldehyde group (-CHO. The rapid conversion of PR toxin to the other derivatives such as PR imine, PR amide, and PR acid, based on conditions available reflects their unstability and degradative aspects. Since the PR toxin-induced toxicity could not be eliminated safely, the assessment of dose-response and other pharmacological aspects for its safe consumption is indispensable. The present review describes the natural occurrences, diversity, biosynthesis

  3. PR Toxin - Biosynthesis, Genetic Regulation, Toxicological Potential, Prevention and Control Measures: Overview and Challenges.

    Science.gov (United States)

    Dubey, Manish K; Aamir, Mohd; Kaushik, Manish S; Khare, Saumya; Meena, Mukesh; Singh, Surendra; Upadhyay, Ram S

    2018-01-01

    Out of the various mycotoxigenic food and feed contaminant, the fungal species belonging to Penicillium genera, particularly Penicillium roqueforti is of great economic importance, and well known for its crucial role in the manufacturing of Roquefort and Gorgonzola cheese. The mycotoxicosis effect of this mold is due to secretion of several metabolites, of which PR toxin is of considerable importance, with regard to food quality and safety challenges issues. The food products and silages enriched with PR toxin could lead into damage to vital internal organs, gastrointestinal perturbations, carcinogenicity, immunotoxicity, necrosis, and enzyme inhibition. Moreover, it also has the significant mutagenic potential to disrupt/alter the crucial processes like DNA replication, transcription, and translation at the molecular level. The high genetic diversities in between the various strains of P. roqueforti persuaded their nominations with Protected Geographical Indication (PGI), accordingly to the cheese type, they have been employed. Recently, the biosynthetic mechanism and toxicogenetic studies unraveled the role of ari1 and prx gene clusters that cross-talk with the synthesis of other metabolites or involve other cross-regulatory pathways to negatively regulate/inhibit the other biosynthetic route targeted for production of a strain-specific metabolites. Interestingly, the chemical conversion that imparts toxic properties to PR toxin is the substitution/oxidation of functional hydroxyl group (-OH) to aldehyde group (-CHO). The rapid conversion of PR toxin to the other derivatives such as PR imine, PR amide, and PR acid, based on conditions available reflects their unstability and degradative aspects. Since the PR toxin-induced toxicity could not be eliminated safely, the assessment of dose-response and other pharmacological aspects for its safe consumption is indispensable. The present review describes the natural occurrences, diversity, biosynthesis, genetics

  4. 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

  5. PR Toxin – Biosynthesis, Genetic Regulation, Toxicological Potential, Prevention and Control Measures: Overview and Challenges

    Science.gov (United States)

    Dubey, Manish K.; Aamir, Mohd; Kaushik, Manish S.; Khare, Saumya; Meena, Mukesh; Singh, Surendra; Upadhyay, Ram S.

    2018-01-01

    Out of the various mycotoxigenic food and feed contaminant, the fungal species belonging to Penicillium genera, particularly Penicillium roqueforti is of great economic importance, and well known for its crucial role in the manufacturing of Roquefort and Gorgonzola cheese. The mycotoxicosis effect of this mold is due to secretion of several metabolites, of which PR toxin is of considerable importance, with regard to food quality and safety challenges issues. The food products and silages enriched with PR toxin could lead into damage to vital internal organs, gastrointestinal perturbations, carcinogenicity, immunotoxicity, necrosis, and enzyme inhibition. Moreover, it also has the significant mutagenic potential to disrupt/alter the crucial processes like DNA replication, transcription, and translation at the molecular level. The high genetic diversities in between the various strains of P. roqueforti persuaded their nominations with Protected Geographical Indication (PGI), accordingly to the cheese type, they have been employed. Recently, the biosynthetic mechanism and toxicogenetic studies unraveled the role of ari1 and prx gene clusters that cross-talk with the synthesis of other metabolites or involve other cross-regulatory pathways to negatively regulate/inhibit the other biosynthetic route targeted for production of a strain-specific metabolites. Interestingly, the chemical conversion that imparts toxic properties to PR toxin is the substitution/oxidation of functional hydroxyl group (-OH) to aldehyde group (-CHO). The rapid conversion of PR toxin to the other derivatives such as PR imine, PR amide, and PR acid, based on conditions available reflects their unstability and degradative aspects. Since the PR toxin-induced toxicity could not be eliminated safely, the assessment of dose-response and other pharmacological aspects for its safe consumption is indispensable. The present review describes the natural occurrences, diversity, biosynthesis, genetics

  6. Genetic and biochemical studies of the lipid-containing bacteriophage PR4

    International Nuclear Information System (INIS)

    Vanden Boom, T.J.

    1989-01-01

    Bacteriophage PR4 is a lipid-containing bacterial virus able to infect Escherichia coli and Salmonella typhimurium. The icosahedral virion consists of an external protein capsid layer which surrounds a membrane vesicle enclosed ds DNA genome. The author has analyzed the time course of phage PR4 protein synthesis and have identified at least 34 proteins present in phage infected cells not detected in uninfected control cultures. In addition, he has isolated a more extensive set of conditional-lethal nonsense mutants of this virus. This collection of mutants permitted the identification of seven additional phage PR4 gene products, including the terminal genome protein and an accessory lytic factor. The present collection of phage PR4 mutants has been assigned to 19 distinct genetic groups on the basis of genetic complementation tests and sodium dodecyl sulfate polyacrylamide gel electrophoresis analysis of the proteins produced in mutant-infected UV-irradiated cells. A restriction endonuclease map of the phage PR4 genome was constructed which includes 59 sites for ten restriction endonucleases. In addition, he has constructed a collection of recombinant plasmids containing subgenomic DNA fragments of bacteriophage PR4. He has used this collection of plasmids to generate a physical-genetic map of the PR4 genome. The physical-genetic map localizes mutations in 13 phage PR4 genetic groups on the viral DNA molecule. To investigate the role of phosphatidylglycerol (PG) in phage assembly and infectivity, he propagated PR4 on an E. coli mutant defective in PG synthesis. The PG content of phage PR4 grown on the mutant host accounted for 0.4% of the total viral phospholipids, representing a 90-fold decrease in PG relative to the PG content of phage grown on a wild type host

  7. Polar and Magnetic Layered A Site and Rock Salt B Site-Ordered NaLnFeWO6 (Ln = La, Nd) Perovskites

    Energy Technology Data Exchange (ETDEWEB)

    Tetuerto, Maria [State University of New Jersey, The; Li, Mang-Rong [State University of New Jersey, The; Ignatov, Alexander [State University of New Jersey, The; Croft, Mark [State University of New Jersey, The; Ramanujachary, Kandalam V. [Rowan University; Chi, Songxue [ORNL; Hodges, Jason P [ORNL; Dachraoui, W. [University of Antwerp; Hadermann, Joke [University of Antwerp; Thao Tran, T. [University of Houston, Houston; Shiv Halasyamani, P. [University of Houston, Houston; Grams, C. [Universitat zu Koln, Koln, Germany; Hemberger, J. [Universitat zu Koln, Koln, Germany; Greenblatt, M. [State University of New Jersey, The

    2013-01-01

    We have expanded the double perovskite family of materials with the unusual combination of layered order in the A sublattice and rock salt order over the B sublattice to compounds NaLaFeWO6 and NaNdFeWO6. The materials have been synthesized and studied by powder X-ray diffraction, neutron diffraction, electron diffraction, magnetic measurements, X-ray absorption spectroscopy, dielectric measurements, and second harmonic generation. At room temperature, the crystal structures of both compounds can be defined in the noncentrosymmetric monoclinic P21 space group resulting from the combination of ordering both in the A and B sublattices, the distortion of the cell due to tilting of the octahedra, and the displacement of certain cations. The magnetic studies show that both compounds are ordered antiferromagnetically below TN 25 K for NaLaFeWO6 and at 21 K for NaNdFeWO6. The magnetic structure of NaNdFeWO6 has been solved with a propagation vector k = (1/2 0 1/2) as an antiferromagnetic arrangement of Fe and Nd moments. Although the samples are potential multiferroics, the dielectric measurements do not show a ferroelectric response.

  8. Thermochemistry of rare earth doped uranium oxides LnxU1-xO2-0.5x+y (Ln = La, Y, Nd)

    Science.gov (United States)

    Zhang, Lei; Navrotsky, Alexandra

    2015-10-01

    Lanthanum, yttrium, and neodymium doped uranium dioxide samples in the fluorite structure have been synthesized, characterized in terms of metal ratio and oxygen content, and their enthalpies of formation measured by high temperature oxide melt solution calorimetry. For oxides doped with 10-50 mol % rare earth (Ln) cations, the formation enthalpies from constituent oxides (LnO1.5, UO2 and UO3 in a reaction not involving oxidation or reduction) become increasingly exothermic with increasing rare earth content, while showing no significant dependence on the varying uranium oxidation state. The oxidation enthalpy of LnxU1-xO2-0.5x+y is similar to that of UO2 to UO3 for all three rare earth doped systems. Though this may suggest that the oxidized uranium in these systems is energetically similar to that in the hexavalent state, thermochemical data alone can not constrain whether the uranium is present as U5+, U6+, or a mixture of oxidation states. The formation enthalpies from elements calculated from the calorimetric data are generally consistent with those from free energy measurements.

  9. Luminescent properties of complexly substituted oxides Ме2Ln8 (XO46O2 (Me=Sr, Ca; Ln=La, Gd, Eu; X= Si, P

    Directory of Open Access Journals (Sweden)

    A. A. Vasin

    2014-11-01

    Full Text Available In the current work it is established that the maximum intensity of a luminescence of crystalline phosphors with structure silicate-apatite of general formulae: Ca2Eu8Si6(1-xP6xO26, Sr2Gd7.2Eu0.8Si6(1-xP6xO26 and Ca2La8(1-xEu8xSi6O26 is reached at concentration of europium equal 0,15. The maximum intensity of a luminescence of these substances, at replacement in an anion sublattice of tetrahedrons [SiO4]4- on tetrahedrons [PO4]3- takes place at concentration of phosphorus 0,05.

  10. Chemical durability and resistance to irradiation of LnYSiAlO (Ln=La or Ce) glasses, potential immobilization matrix of minor actinides

    International Nuclear Information System (INIS)

    Gavarini, St.

    2002-11-01

    Rare earth aluminosilicate glasses are known for their interesting mechanical and optical properties. Recent studies have shown that their chemical durability was very good too, such they have the potential to be used in the nuclear industry for the specific immobilization of trivalent actinides. Initial dissolution rates of LaYSiAlO and CeYSiAlO were determined using a Soxhlet device (dynamic leaching). The differences linked to the nature of the rare earth element were studied by synthesizing analogous glasses that only differed in their rare earth element composition (%at.): Y-5%, La-5 %, Si-15%, Al-10% O-65%. The influence of pH on the dissolution mechanisms and kinetics was also studied by static leaching tests performed in dilute solutions of NaOH or HNO 3 . Electronic defects and collision cascades, induced by a-disintegration of radioelements confined in storage matrix, can cause important modifications in the glass structure and, thus, influence its chemical durability. To simulate these effects, glass samples were irradiated with β particles and heavy ions accelerated to 2,5 MeV and 200 keV, respectively. Monoliths were then leached in static bi-distilled water (pH≥≥ 5.5) for one month in an autoclave heated to 90 degrees C. Initially, the structural changes caused by irradiation were determined using Raman, NMR and EPR spectroscopies. Ion μ-beams, SEM-EDS and XPS analysis were also performed to evaluate the potential modifications of the superficial composition. Finally, the leaching behavior was studied, for both irradiated and unirradiated samples, through solution and solid elementary characterization. (author)

  11. ALnS.sub.2./sub.:RE (A=K, Rb; Ln=La, Gd, Lu, Y): new optical materials family

    Czech Academy of Sciences Publication Activity Database

    Jarý, Vítězslav; Havlák, Lubomír; Bárta, J.; Mihóková, Eva; Buryi, Maksym; Nikl, Martin

    2016-01-01

    Roč. 170, č. 2 (2016), s. 718-735 ISSN 0022-2313 R&D Projects: GA ČR GA13-09876S; GA TA ČR TA01011017 Institutional support: RVO:68378271 Keywords : ternary sulfide * luminescence * x-ray diffraction * EPR * rare-earth doping * white LED Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 2.686, year: 2016

  12. Optical, structural and paramagnetic properties of Eu-doped ternary sulfides ALnS.sub.2./sub. (A = Na, K, Rb; Ln = La, Gd, Lu, Y)

    Czech Academy of Sciences Publication Activity Database

    Jarý, Vítězslav; Havlák, Lubomír; Bárta, J.; Buryi, Maksym; Mihóková, Eva; Rejman, M.; Laguta, Valentyn; Nikl, Martin

    2015-01-01

    Roč. 8, č. 10 (2015), s. 6978-6998 ISSN 1996-1944 R&D Projects: GA TA ČR TA04010135; GA MŠk(CZ) LM2011029; GA MŠk LO1409 Grant - others:SAFMAT(XE) CZ.2.16/3.1.00/22132 Institutional support: RVO:68378271 Keywords : luminescence * white light emitting diode * ternary sulfide * EPR Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 2.728, year: 2015

  13. Structure of trihydrated rare-earth acid diphosphates LnHP2O7·3H2O (Ln=La, Er)

    International Nuclear Information System (INIS)

    Ben Moussa, S.; Ventemillas, S.; Cabeza, A.; Gutierrez-Puebla, E.; Sanz, J.

    2004-01-01

    In trihydrated lanthanum acid-diphosphates LnHP 2 O 7 ·3H 2 O, prepared from acid LnCl 3 and Na 4 P 2 O 7 solutions (pH=1), two crystal forms were obtained. Layered structures of two representative members of this family have been determined by single-crystal X-ray diffraction (XRD) technique. In the case of orthorhombic LaHP 2 O 7 ·3H 2 O (type I), lanthanum cations are ninefold coordinated and diphosphate groups adopt a staggered (alternated) configuration. In the case of triclinic ErHP 2 O 7 ·3H 2 O (type II), erbium cations are eightfold coordinated and diphosphate groups adopt an eclipsed configuration. In agreement with Infrared (IR) spectroscopic data, a bended configuration for diphosphate groups has been deduced. In both structures, one-dimensional chains of edge-sharing rare-earth polyhedra are linked together by diphosphate groups to form the phosphate layers. In both diphosphates, PO 4 and HPO 4 environments have been identified by 31 P MAS-NMR technique. In the two compounds, OH groups of HPO 4 tetrahedra point out of diphosphate planes interacting with adjacent layers. In La-diphosphate, the interaction between HPO 4 groups and water molecules of adjacent layers is favored; however, in Er-diphosphate, the interaction between phosphate acid groups of contiguous layers is produced. Based on structural information deduced, differences detected in IR and NMR spectra of two disphosphates are discussed

  14. Las prácticas espirituales del eremitismo peninsular altomedieval

    Directory of Open Access Journals (Sweden)

    Vanessa Jimeno Guerra

    2011-01-01

    Full Text Available Durante la antigüedad tardía comenzó a desarrollarse en la Península Ibérica un ascetismo cristiano basado en los modos de vida llevados a cabo por los Padres del Desierto y predicados en las Sagradas Escrituras. Sin embargo, las semejanzas que este fenómeno presenta con respecto a algunas de las doctrinas filosóficas griegas de época helenística son evidentes. Así, el aislamiento, la contemplación o el ayuno como medio de purificación son prácticas comunes a ambos. De esta manera, el presente trabajo pretende ofrecer un análisis del panorama del eremitismo peninsular durante la Alta Edad Media en relación con dichos sistemas filosóficos.During the late antiquity started to develope a christian asceticism in the Iberian Peninsula which were based on the ways of life of the Fathers of the desert and preached in the Holy Scriptures. However, this phenomenom looks like some of the Greek philosophical doctrines of the Hellenistical period. Thus, the loneliness, the meditation or the fast as way of purification are common practices for both of them. This way, the present study tries to offer an analysis of the peninsular hermits panorama during the High Middle Ages compared to these philosophical systems.

  15. Prospectiva, fundamentos y un caso práctico

    Directory of Open Access Journals (Sweden)

    Franklin Serrano

    1994-05-01

    Full Text Available RESUMEN La aparición de la informática y su alto desarrollo alcanzado, ha generado  un movimiento modernizador de las empresas, tendiente especialmente a lograr sobrevivir  y proponerse  a tono con las nuevas   tendencias competitiva. La utilización de las nuevas tecnologías, nuevas formas de planear  y nuevas formas de gerenciar. Estos cambios se imponen como resultados  de las actuales tendencias mundiales del mercado, los nuevos conocimientos y el cambio en la forma de estructurar el pensamiento. El hombre hace tiempo aceptó la teoría de que el mismo forja su propio destino, y es así como ha recurrido constantemente a la utilización y creación de técnicas que facilitan la proyección de un futuro acorde con sus deseos. El presente escrito tiene por objeto, exponer los elementos básicos de los Fundamentos y las técnicas de escenarios para el manejo de la Prospectiva. Como experiencia práctica se presenta un estudio de caso sencillo utilizando Software desarrollado por los autores.

  16. Présentation Technique - French version only

    CERN Multimedia

    2003-01-01

    Tuesday 9 September PRESENTATION TECHNIQUE From 09:00 - 12:00 - bldg. 40, S2-B01 Techniques de mesure: Acquisition, analyse et présentation avec LabVIEW 7 Express National Instruments Switzerland Avec LabVIEW 7 Express, National Instruments inaugure une nouvelle ère pour la programmation graphique dans le monde de la mesure et de l'automatisation. Pour la première fois dans l'histoire de la programmation par flux de données, les antagonismes inconciliables entre la programmation et la configuration se laissent réduire au même dénominateur et sont disponibles dans un environnement de développement intégré. En outre, cette nouvelle version peut-être supportée par une plus large palette de plates-formes et de matériels cibles : de Windows, Linux ou Mac OS X jusqu'aux PDA (assistants personnels) ou aux FPGA embarqués. Avec LabVIEW 7 Express, vous disposez d'un outil logiciel, qui vous permet de construire encore plus vite, plus facilement et à moindres frais vos...

  17. Promiscuous 2-aminothiazoles (PrATs): a frequent hitting scaffold.

    Science.gov (United States)

    Devine, Shane M; Mulcair, Mark D; Debono, Cael O; Leung, Eleanor W W; Nissink, J Willem M; Lim, San Sui; Chandrashekaran, Indu R; Vazirani, Mansha; Mohanty, Biswaranjan; Simpson, Jamie S; Baell, Jonathan B; Scammells, Peter J; Norton, Raymond S; Scanlon, Martin J

    2015-02-12

    We have identified a class of molecules, known as 2-aminothiazoles (2-ATs), as frequent-hitting fragments in biophysical binding assays. This was exemplified by 4-phenylthiazol-2-amine being identified as a hit in 14/14 screens against a diverse range of protein targets, suggesting that this scaffold is a poor starting point for fragment-based drug discovery. This prompted us to analyze this scaffold in the context of an academic fragment library used for fragment-based drug discovery (FBDD) and two larger compound libraries used for high-throughput screening (HTS). This analysis revealed that such "promiscuous 2-aminothiazoles" (PrATs) behaved as frequent hitters under both FBDD and HTS settings, although the problem was more pronounced in the fragment-based studies. As 2-ATs are present in known drugs, they cannot necessarily be deemed undesirable, but the combination of their promiscuity and difficulties associated with optimizing them into a lead compound makes them, in our opinion, poor scaffolds for fragment libraries.

  18. Práticas alimentares no primeiro ano de vida

    Directory of Open Access Journals (Sweden)

    Ana Paula Esmeraldo Lima

    2011-10-01

    Full Text Available O estudo buscou analisar a literatura publicada referente às práticas alimentares no primeiro ano de vida de filhos de mães adolescentes, por meio de uma revisão integrativa nas bases de dados Lilacs, Medline e Cochrane, no período de 2000 a 2010. Foram utilizadas as palavras-chave: adolescente, aleitamento materno, alimentação mista e nutrição do lactente, sendo selecionados onze artigos científicos, que compuseram a amostra do estudo. Os resultados apontaram a incipiência de pesquisas publicadas sobre o tema proposto, sobretudo para as que versam sobre alimentação complementar, desvelando uma lacuna na produção mundial sobre o tema. Novas pesquisas, portanto, precisam ser desenvolvidas com foco em mães adolescentes, devendo-se explorar a alimentação infantil em toda sua dimensão.

  19. Convivencia escolar. Un estudio sobre buenas prácticas

    Directory of Open Access Journals (Sweden)

    María José Caballero Grande

    2010-06-01

    Full Text Available Este trabajo de investigación se centra en la convivencia escolar y puede enmarcarse en la línea de educación para la paz.La finalidad del mismo ha sido conocer algunas peculiaridades de prácticas educativas  que fomentan la paz y la convivencia en el ámbito escolar. Para esto, se ha recogido información, mediante entrevista estructurada, en diez centros  educativos de la provincia de Granada, acogidos a la Red Andaluza  “Escuela, espacio de paz”, sobre la puesta en marcha, desarrollo y evaluación de actuaciones encaminadas hacia la cohesión del grupo, la gestión democrática de normas, la educación en valores, las habilidades socioemocionales y la regulación pacífica de conflictos.Del análisis de las entrevistas, se desprende que hay una serie de medidas y actuaciones que se llevan a cabo en los centros educativos que favorecen la buena convivencia. La necesidad de cooperación entre todos los actores intervinientes en el proceso educativo o  la importancia de sistematizar e institucionalizar el trabajo que eduque para el fomento de una cultura de paz, conforman entre otras las conclusiones a las que se llega en este estudio.

  20. Silencing of acidic pathogenesis-related PR-1 genes increases extracellular beta-(1 -> 3)-glucanase activity at the onset of tobacco defence reactions

    DEFF Research Database (Denmark)

    Riviere, M.P.; Marais, A.; Ponchet, M.

    2008-01-01

    silenced. Plants lacking extracellular PR-1s were more susceptible than wild-type plants to the oomycete Phytophthora parasitica but displayed unaffected systemic acquired resistance and developmental resistance to this pathogen. Treatment with salicylic acid up-regulates the PR-1g gene, encoding a basic...... protein of the PR-1 family, in PR-1-deficient tobacco, indicating that PR-1 expression may repress that of PR-1g. This shows that acidic PR-1s are dispensable for expression of salicylic acid-dependent acquired resistances against P. parasitica and may reveal a functional overlap in tobacco defence......The class 1 pathogenesis-related (PR) proteins are thought to be involved in plant defence responses, but their molecular functions are unknown. The function of PR-1 was investigated in tobacco by generating stable PR-1a-silenced lines in which other acidic PR-1 genes (PR-1b and PR-1c) were...

  1. Application of the GIF PR and PP methodology to a commercial fast reactor system for a preliminary analysis of PR scenarios

    International Nuclear Information System (INIS)

    Rossi, Fabiana

    2015-01-01

    The Generation IV International Forum (GIF) Proliferation Resistance and Physical Protection (PR and PP) Working Group has developed a methodology for the PR and PP evaluation of the next generation Nuclear Energy Systems (NESs). Following the methodology proposed by the working group, applicable to assessing the proliferation resistance of an NES and its individual elements, the main objective of this work is to apply the methodology to show an example of how its results could be used by designers to improve the PR of the system. In this study, the reactor site of a hypothetical and commercial sodium‑cooled fast neutron nuclear reactor system (SFR) was used as the target NES for the application of the methodology. The design of this SFR is based on the layout of the Japanese Sodium Fast Reactor (JSFR) with a safeguards design based on the safeguards approach of the Japanese prototype fast breeder reactor Monju. The methodology is applied to all the PR scenarios described in the methodology: diversion, misuse and breakout. The methodology was first applied to the SFR to check if this system meets the target of PR as described in the GIF goal; secondly, a comparison between the SFR and a light water reactor (LWR) with an open fuel cycle was performed to evaluate if and how it would be possible to improve the PR and PP of the SFR. The LWR layout is based on the European Pressurized Water Reactor. The comparison was implemented according to the following example development target: achieving proliferation resistance to material diversion similar or superior to domestic and international advanced LWR. Three main actions were performed: implement the evaluation methodology based on its assumptions; characterize the PR and PP for the nuclear energy system applying the methodology to the SFR; and identify recommendations for system designers through comparing the SFR with the LWR.

  2. Practicality of the cyclotron production of radiolanthanide 142Pr. A potential for therapeutic applications and biodistribution studies

    International Nuclear Information System (INIS)

    Mahdi Sadeghi; Bakht, M.K.; Leila Mokhtari

    2011-01-01

    Radiolanthanide praseodymium-142 (T 1/2 = 19.12 h, E β - = 2.162 MeV (96.3%), E γ = 1575 keV (3.7%)) due to its high β-emission and low specific γ-emission could not only be a therapeutic radionuclide, but also a suitable radionuclide in order for biodistribution studies. Conventionally, 142 Pr produces via 141 Pr(n,γ) 142 Pr reaction by irradiation in a low-fluence reactor and this study evaluates cyclotron reaction production of it. 142 Pr excitation function via nat La(α,n) 142 Pr, 142 Ce(p,n) 142 Pr, and nat Pr(d,p) 142 Pr reactions were calculated by TALYS-1.2 and EMPIRE-2.19beta codes, and with the data taken from the TENDL-2010 database. In addition, we compared them with the reported measurement by experimental data. Requisite thickness of targets was obtained by SRIM-2010 code for each reaction. The 142 Pr production yield was evaluated with attention to excitation function and stopping power. Similar to reactor produced 142 Pr; 141 Pr impurity exists in cyclotron produced 142 Pr while it could not be separated by chemical methods. Therefore, cyclotron and reactor produced 142 Pr will be in carrier added form. (author)

  3. Organolanthanide-Catalyzed Cyclodimerizations of Disubstituted Alkynes

    NARCIS (Netherlands)

    Heeres, H.J.; Heeres, Andre; Teuben, J.H.

    The lanthanide alkyls Cp2*LnCH(SiMe3)2 (Ln = La, Ce) are efficient catalysts for the cyclodimerization of 2-alkynes MeC≡CR (R = Me, Et, n-Pr) to 1,2-disubstituted 3-alkylidenecyclobutenes. The first step in the reaction is a propargylic metalation of the α-methyl group, giving Cp*2LnCH2C≡CR

  4. Synthesis and characterisation of some lanthanide perchlorate complexes of 4-nitrosoantipyrine

    International Nuclear Information System (INIS)

    Jayasankar, H.; Indrasenan, P.

    1988-01-01

    Seven lanthanide perchlorate complexes of 4-nitrosoantipyrine (NAP) of the general formula [Ln(NAP) 4 ClO 4 ](ClO 4 ) 2 (where Ln=La, Pr, Nd, Sm, Gd, Dy and Y), have been synthesised and characterised by elemental analyses, molecular weights, conductances, magnetic moments and infrared and electronic spectral data. In these nine-coordinated complexes, all the four NAP molecules are coordinated bidentately and one of the perchlorate groups is coordinated monodentately. (author). 12 refs

  5. Pressure induced Amorphization of Ln1/3(Nb,Ta)O3

    International Nuclear Information System (INIS)

    Melchior, A.; Noked, O.; Sterer, E.; Shuker, R.

    2014-01-01

    The research focuses on the phenomenon of pressure induced amorphization (PIA) in Ln1/3MO3, Ln - La,Pr,Nd and M-Nb,Ta. In most pressure induced phase transitions the material changes from a crystalline phase to another crystalline phase. However, if this transition is kinetically hindered, the increased free energy due to the applied pressure will result in a structural collapse to an amorphous intermediate phase. This phenomenon is known as pressure induced amorphization

  6. Molecular cloning and characterization of two novel genes from hexaploid wheat that encode double PR-1 domains coupled with a receptor-like protein kinase

    Science.gov (United States)

    Hexaploid wheat (Triticum aestivum L.) contains at least 23 TaPr-1 genes encoding the group 1 pathogenesis-related (PR-1) proteins as identified in our previous work. Here we report the cloning and characterization of TaPr-1-rk1 and TaPr-1-rk2, two novel genes closely related to the wheat PR-1 famil...

  7. Avaliação pré-anestésica e redução dos custos do preparo pré-operatório

    Directory of Open Access Journals (Sweden)

    Márcia Rodrigues Neder Issa

    2011-02-01

    Full Text Available JUSTIFICATIVA E OBJETIVOS: A avaliação pré-anestésica (APA é fundamental no preparo do paciente cirúrgico. Entre suas muitas vantagens, destaca-se a redução dos custos com o preparo pré-operatório. Embora estudos prévios tenham constatado esse benefício, não é certo que ele se aplique adequadamente em nosso meio. O objetivo deste estudo foi comparar os custos do preparo pré-operatório realizado pelo cirurgião com os custos estimados a partir da APA. Paralelamente, comparou-se a classificação do estado físico da American Society of Anesthesiologists (ASA determinada pelo anestesiologista ou por outros especialistas. MÉTODO: Duzentos pacientes candidatos a procedimentos cirúrgicos ou diagnósticos eletivos, cujo preparo pré-operatório foi orientado pelo cirurgião, foram submetidos à APA após internação hospitalar. O anestesiologista determinou os exames complementares ou as consultas especializadas e necessárias a cada paciente. Foram comparados o número e os custos dos exames ou consultas indicados pelo anestesiologista com aqueles realizados no preparo pré-operatório. Comparou-se também a classificação da ASA determinada pelo anestesiologista ou pelo médico que realizou a consulta especializada. RESULTADOS: Dos 1.075 exames complementares realizados, 55,8% não estavam indicados, o que equivaleu a uma fração de 50,8% do custo total com exames. O anestesiologista considerou que 37 pacientes (18,5% não precisariam realizar exames. O custo do preparo orientado pelo cirurgião foi 25,11% maior do que o custo estimado a partir da avaliação pré-anestésica, sendo essa diferença estatisticamente significante (p < 0,01. Houve discordância na classificação da ASA em 9,3% dos pacientes avaliados pelo especialista. CONCLUSÕES: O preparo pré-operatório baseado na avaliação pré-anestésica criteriosa pode resultar em significativa redução dos custos quando comparado ao preparo orientado pelo cirurgi

  8. An insight to the molecular interactions of the FDA approved HIV PR drugs against L38L↑N↑L PR mutant

    Science.gov (United States)

    Sanusi, Zainab K.; Govender, Thavendran; Maguire, Glenn E. M.; Maseko, Sibusiso B.; Lin, Johnson; Kruger, Hendrik G.; Honarparvar, Bahareh

    2018-03-01

    The aspartate protease of the human immune deficiency type-1 virus (HIV-1) has become a crucial antiviral target in which many useful antiretroviral inhibitors have been developed. However, it seems the emergence of new HIV-1 PR mutations enhances drug resistance, hence, the available FDA approved drugs show less activity towards the protease. A mutation and insertion designated L38L↑N↑L PR was recently reported from subtype of C-SA HIV-1. An integrated two-layered ONIOM (QM:MM) method was employed in this study to examine the binding affinities of the nine HIV PR inhibitors against this mutant. The computed binding free energies as well as experimental data revealed a reduced inhibitory activity towards the L38L↑N↑L PR in comparison with subtype C-SA HIV-1 PR. This observation suggests that the insertion and mutations significantly affect the binding affinities or characteristics of the HIV PIs and/or parent PR. The same trend for the computational binding free energies was observed for eight of the nine inhibitors with respect to the experimental binding free energies. The outcome of this study shows that ONIOM method can be used as a reliable computational approach to rationalize lead compounds against specific targets. The nature of the intermolecular interactions in terms of the host-guest hydrogen bond interactions is discussed using the atoms in molecules (AIM) analysis. Natural bond orbital analysis was also used to determine the extent of charge transfer between the QM region of the L38L↑N↑L PR enzyme and FDA approved drugs. AIM analysis showed that the interaction between the QM region of the L38L↑N↑L PR and FDA approved drugs are electrostatic dominant, the bond stability computed from the NBO analysis supports the results from the AIM application. Future studies will focus on the improvement of the computational model by considering explicit water molecules in the active pocket. We believe that this approach has the potential to provide

  9. An insight to the molecular interactions of the FDA approved HIV PR drugs against L38L↑N↑L PR mutant.

    Science.gov (United States)

    Sanusi, Zainab K; Govender, Thavendran; Maguire, Glenn E M; Maseko, Sibusiso B; Lin, Johnson; Kruger, Hendrik G; Honarparvar, Bahareh

    2018-03-01

    The aspartate protease of the human immune deficiency type-1 virus (HIV-1) has become a crucial antiviral target in which many useful antiretroviral inhibitors have been developed. However, it seems the emergence of new HIV-1 PR mutations enhances drug resistance, hence, the available FDA approved drugs show less activity towards the protease. A mutation and insertion designated L38L↑N↑L PR was recently reported from subtype of C-SA HIV-1. An integrated two-layered ONIOM (QM:MM) method was employed in this study to examine the binding affinities of the nine HIV PR inhibitors against this mutant. The computed binding free energies as well as experimental data revealed a reduced inhibitory activity towards the L38L↑N↑L PR in comparison with subtype C-SA HIV-1 PR. This observation suggests that the insertion and mutations significantly affect the binding affinities or characteristics of the HIV PIs and/or parent PR. The same trend for the computational binding free energies was observed for eight of the nine inhibitors with respect to the experimental binding free energies. The outcome of this study shows that ONIOM method can be used as a reliable computational approach to rationalize lead compounds against specific targets. The nature of the intermolecular interactions in terms of the host-guest hydrogen bond interactions is discussed using the atoms in molecules (AIM) analysis. Natural bond orbital analysis was also used to determine the extent of charge transfer between the QM region of the L38L↑N↑L PR enzyme and FDA approved drugs. AIM analysis showed that the interaction between the QM region of the L38L↑N↑L PR and FDA approved drugs are electrostatic dominant, the bond stability computed from the NBO analysis supports the results from the AIM application. Future studies will focus on the improvement of the computational model by considering explicit water molecules in the active pocket. We believe that this approach has the potential to

  10. 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.)

  11. Donor doping process and white light generation in CaMoO4 powders with multivalence Pr codoping

    International Nuclear Information System (INIS)

    Zhu Fang; Xiao Zhisong; Zhang Feng; Yan Lu; Huang Anping

    2011-01-01

    Both trivalent praseodymium (Pr 3+ ) and quadrivalent praseodymium (Pr 4+ ) were doped in molybdate powders. Visible emission from matrix was enhanced by multivalent Pr codoping. It was proposed that Pr 3+ ions was donor and supplied quasi-free electron when Pr 3+ took place the Pr 4+ sites. The result showed that multivalence codoping would be an effective way to enhance emission of CaMoO 4 . White light can be generated from Ca 0.98 Pr 0.02 MoO 4 powder via combination of broadband emissions originated from CaMoO 4 matrix and radiative transition of Pr 3+ . It showed warm white light with T c of 3450 K that implies promising application in white light emitting diodes (LEDs).

  12. Polli prügila rahastamise otsus vaidluste rägastikus. Kas riigiabi või mitte? / Koit Brinkmann

    Index Scriptorium Estoniae

    Brinkmann, Koit

    2011-01-01

    Keskkonnainvesteeringute Keskuse (KIK) otsusesse, millega eraldati OÜ Polli Prügilale toetus prügila rajamiseks Lõuna-Eestisse, lisati punkt, mille kohaselt peab Euroopa Komisjonilt saama kinnituse, et tegemist ei ole riigiabiga

  13. 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

  14. Study into non-quasibinary sections of Pr2S3-Bi2S3-Pr2O3 triple system (Bi2S3)0. 45(Pr2O3)0. 55 - (Bi2S3)0. 45(Pr2S3)0. 55 and (Bi2S3)0. 75 (Pr2S3)0. 25 - (Bi2S3)0. 75(Pr2O3)0. 25

    OpenAIRE

    НЕЙМАТОВА А.В.; МАМЕДОВ Ф.М.; БАХТИЯРЛЫ И.Б.

    2016-01-01

    Методами дифференциальнo-термическoго (ДТ), рентгенофазового (РФ), микроструктурного (МС) методов анализа исследованы неквазибинарные разрезы (Bi2S3)0.45(Pr2O3)0.55 (Bi2S3)0.45(Pr2S3)0.55 и (Bi2S3)0.75 (Pr2S3)0.25 (Bi2S3)0.75(Pr2O3)0.25 тройной системы Pr2S3-Bi2S3-Pr2O3 построена диаграмма состояния, определены координанты нони моновариантныхравновесий....

  15. 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.

  16. 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.

  17. Downconversion in Pr3+–Yb3+ co-doped ZBLA fluoride glasses

    International Nuclear Information System (INIS)

    Maalej, O.; Boulard, B.; Dieudonné, B.; Ferrari, M.; Dammak, M.; Dammak, M.

    2015-01-01

    Fluorozirconate ZBLA glasses with molar composition 57ZrF 4 –34BaF 2 –5LaF 3 –4AlF 3 –0.5PrF 3 –xYbF 3 (from x=0 to 10) were synthesized to evaluate the rate of the conversion of visible photons into infrared photons. The emission spectra in the near infrared (NIR) at 950–1100 nm and the luminescence decays in the visible and NIR indicate an energy transfer from Pr 3+ to Yb 3+ upon blue excitation of Pr 3+ at 440 nm. The energy transfer efficiency increases with Yb 3+ concentration to reach 86% with 0.5Pr 3+ –10Yb 3+ co-doping (in mol%). However, the quenching of the Yb 3+ emission strongly reduces the efficiency of the downconversion process: the decay time values decrease from 600 µs (x=0.5 mol%) to 85 µs (x=10 mol%). - Highlights: • We synthesized 0.5Pr 3+ –xYb 3+ co-doped ZBLA glasses (from x=0 to 10 mol %). • Photoluminescence of Yb 3+ was observed at 980 nm under blue excitation. • Time resolved measurements have been performed in the visible and near infrared. • Energy transfer efficiency from Pr 3+ to Yb 3+ reaches 86% in 0.5 Pr 3+ –10Yb 3+ glass

  18. The relationship of structure to superconductivity in the Pr-Ba-Cu-O system

    Science.gov (United States)

    Minseo, P.

    1994-05-01

    The relation of structure to lack of superconductivity in Pr-Ba-Cu-O was systematically investigated. First, the phase equilibria of this system was studied to find the processing parameters which maximize the cation-site ordering between Pr and Ba ions. Second, a comparative study between superconducting Nd-Ba-Cu-O and nonsuperconducting Pr-Ba-Cu-O was performed by forming solid-solution Nd-Pr-Ba-Cu-O. The relation between structure and superconductivity in Nd(1-x)Pr(x)Ba2Cu3O(7-delta) is investigated. T sub c decreases monotonically with increasing x and superconductivity disappears at around x = 0.3 to 0.4. T sub c is enhanced by 10 K when the sample is processed at an oxygen partial pressure (PO2) of 0.01 atm, followed by oxygenation at 450 C. Depression of T sub c as a function of x and PO2 is explained in terms of a charge-transfer model. It is suggested that destruction of superconductivity in the RE(1-x)Pr(x)Ba2Cu3O(7-delta) (RE=rare-earth) system can be viewed as disruption of four-fold planar coordinated Cu ions in the chain-site due to permanent occupation of extra Pr ions on Ba sites.

  19. Acetylcholinesterase triggers the aggregation of PrP 106-126

    International Nuclear Information System (INIS)

    Pera, M.; Roman, S.; Ratia, M.; Camps, P.; Munoz-Torrero, D.; Colombo, L.; Manzoni, C.; Salmona, M.; Badia, A.; Clos, M.V.

    2006-01-01

    Acetylcholinesterase (AChE), a senile plaque component, promotes amyloid-β-protein (Aβ) fibril formation in vitro. The presence of prion protein (PrP) in Alzheimer's disease (AD) senile plaques prompted us to assess if AChE could trigger the PrP peptides aggregation as well. Consequently, the efficacy of AChE on the PrP peptide spanning-residues 106-126 aggregation containing a coumarin fluorescence probe (coumarin-PrP 106-126) was studied. Kinetics of coumarin-PrP 106-126 aggregation showed a significant increase of maximum size of aggregates (MSA), which was dependent on AChE concentration. AChE-PrP 106-126 aggregates showed the tinctorial and optical amyloid properties as determined by polarized light and electronic microscopy analysis. A remarkable inhibition of MSA was obtained with propidium iodide, suggesting that AChE triggers PrP 106-126 and Aβ aggregation through a similar mechanism. Huprines (AChE inhibitors) also significantly decreased MSA induced by AChE as well, unveiling the potential interest for some AChE inhibitors as a novel class of potential anti-prion drugs

  20. The future of pre-exposure prophylaxis (PrEP) for human immunodeficiency virus (HIV) infection.

    Science.gov (United States)

    Özdener, Ayşe Elif; Park, Tae Eun; Kalabalik, Julie; Gupta, Rachna

    2017-05-01

    People at high risk for HIV acquisition should be offered pre-exposure prophylaxis (PrEP). Tenofovir disoproxil fumarate (TDF)/emtricitabine (FTC) is currently the only medication recommended for pre-exposure prophylaxis (PrEP) by the Centers for Disease Control and Prevention (CDC) in people at high risk for HIV acquisition. This article will review medications currently under investigation and the future landscape of PrEP therapy. Areas covered: This article will review clinical trials that have investigated nontraditional regimens of TDF/FTC, antiretroviral agents from different drug classes such as integrase strand transfer inhibitors (INSTI), nucleoside reverse transcriptase inhibitors (NRTI), and non-nucleoside reverse transcriptase inhibitors (NNRTI) as potential PrEP therapies. Expert commentary: Currently, there are several investigational drugs in the pipeline for PrEP against HIV infection. Increased utilization of PrEP therapy depends on provider identification of people at high risk for HIV transmission. Advances in PrEP development will expand options and access for people and reduce the risk of HIV acquisition.