| 1. |
- Silvestri, M., et al.
(författare)
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Fine specificity and neutralizing activity of human serum antibodies directed to the major antigenic region on gp 116 of human cytomegalovirus
- 1993
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Ingår i: Serodiagnosis and Immunotherapy in Infectious Disease. - 0888-0786. ; 5:4, s. 209-216
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Tidskriftsartikel (refereegranskat)abstract
- The human antibody response to the conserved neutralization-related site on the gp 116 of human cytomegalovirus (HCMV) was investigated in healthy blood donors by the use of synthetic peptides. Anti-HCMV positive sera investigated in ELISA gave a reactivity of 48-56% with the peptide T7-13 (amino acids (aa) 67-86). Though epitope mapping revealed several individual fine specificities within this region, the average reactivity pattern was similar to that of the human monoclonal antibody (MAb) ITC88, the binding of which has been localized to aa 69-80. By the use of superparamagnetic Dynabeads coated with the peptide T7-13, serum antibodies were affinity isolated and the neutralizing activity was investigated. A clear reduction in infectivity was seen only with antibodies from one out of four sera and this serum exhibited a fine specificity nearly identical to that of MAb ITC88. A complete adsorption of antibodies to this site was not achieved, yet the results imply that antibodies against this region do not constitute a major part of the HCMV-neutralizing activity in human serum. The potent complement-independent neutralizing activity of antibodies directed to this site nevertheless suggests that it will contribute beneficially to a subunit vaccine.
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| 2. |
- Akner, Gunnar, 1953-, et al.
(författare)
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Immunocytochemical localization of glucocorticoid receptor in human gingival fibroblasts and evidence for a colocalization of glucocorticoid receptor with cytoplasmic microtubules
- 1990
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Ingår i: European Journal of Cell Biology. - 0171-9335 .- 1618-1298. ; 53:2, s. 390-401
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Tidskriftsartikel (refereegranskat)abstract
- The cellular distribution of the glucocorticoid receptor (GR) in relation to various intracellular and plasma membrane structures in human fibroblasts was studied using indirect immunofluorescence techniques with monoclonal and polyclonal antibodies. During interphase, GR was located predominantly in the cytoplasm, showing a similar pattern as tubulin. In mitotic cells, GR and tubulin were localized in mitotic spindles and in telophase midbodies. Colchicine and vinblastine induced a similar redistribution of GR and tubulin to the cell periphery. This redistribution was reversible for colchicine but not for vinblastine. Vinblastine also induced paracrystals containing GR and tubulin. These results support the hypothesis that GR interacts in vivo with cytoplasmic microtubules.
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| 3. |
- Andersson, Britt M., et al.
(författare)
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Defects and the thermal conductivity of YBa2Cu3O7-d and YBa2Cu4O8
- 1993
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Ingår i: Journal of Alloys and Compounds, volume 195. - : Elsevier Sequoia S.A.. - 0 444 81529 5 ; , s. 655-658
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Konferensbidrag (refereegranskat)abstract
- We present below the first measured data for the thermal diffusivity and the thermal conductivity, λ, of dense, sintered ceramic YBa2Cu4O8 (1-2-4) as a function of temperature T between 40 and 310 K. At 300 K, λ is 6.3 Wm−1K−1, increasing with decreasing T to about 9.5 Wm−1K−1 near Tc. This T dependence is much stronger than in YBa2Cu3O7−δ (1-2-3). Only a very small enhancement is observed in λ below Tc. As in 1-2-3, λ is mainly limited by phonon scattering by defects.
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| 4. |
- Andersson, Britt M., et al.
(författare)
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Electrical resistivity and critical temperature of Bi-based high-Tc superconductors to 1 GPa
- 1990
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Ingår i: High Pressure Research, volumes 3 to 5. - London : Gordon and Breach. - 2881247466 ; 3:1-6, s. 120-122
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Konferensbidrag (refereegranskat)abstract
- We have measured the electrical resistance R of a sintered, two-phase, high-TC superconductor with the nominal composition BiSrCaCu2Ox, as a function of T and p. We find d(lnR)/dp ≃ -0.06 GPa-1 at 295 K, while dTC/dp is 2.5 K/GPa for the phase with Tc ≃ 76 and 2 K/GPa for that with TC ≃ 106 K.
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| 5. |
- Andersson, Britt M., et al.
(författare)
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Electrical transport in dense, bulk YBa2Cu4O8 produced by hot isostatic pressing
- 1990
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Ingår i: Physica B Volumes 165 & 166, Part 2. - : Elsevier B.V.. ; , s. 1699-1700
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Konferensbidrag (refereegranskat)abstract
- Dense (98.5%) bulk sintered specimens of YBa2Cu4O8 have been produced by hot isostatic pressing. Data for the electrical resistivity π versus temperature T and pressure p in the range 70–300 K and 0–0.7 GPa are reported and discussed. The critical current density of the material studied exceeds 100 Acm−2 below 60 K.
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| 6. |
- Andersson, Britt M., et al.
(författare)
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Electrical transport properties of dense bulk YBa2Cu4O8 produced by hot isostatic pressing
- 1990
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Ingår i: Physica. C, Superconductivity. - 0921-4534 .- 1873-2143. ; 170:5-6, s. 521-531
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Tidskriftsartikel (refereegranskat)abstract
- Highly dense sintered YBa2Cu4O8 has been produced by hot isostatic pressing (HIP). The electrical resistivity varrho of this material has been measured as a function of temperature T and pressure varrho in the range 40–650 K and 0–0.7 GPa. Both the temperature dependence and the pressure dependence of varrho are found to be well described by a model based on the standard Bloch-Grüneisen theory. It is pointed out that varrho is liner in T only under isobaric conditions, while varrho is strongly nonlinear in all high-Tc superconductors under isochoric (constant volume) conditions. The critical current density of the material is 900 A/cm2 at 4 K, while the resistivity is 630 μΩ cm at 294 K.
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| 7. |
- Andersson, Britt M., et al.
(författare)
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High-pressure properties of high-Tc superconductor samples produced by hot isostatic pressing
- 1990
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Ingår i: High Pressure Research, volumes 3 to 5. - London : Gordon and Breach. - 2881247466 ; 3:1-6, s. 123-125
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Konferensbidrag (refereegranskat)abstract
- The electrical resistance of dense YBa2Cu3Ox and YBa2Cu4Oy produced by hot isostatic pressing has been measured vs. T and p. At 295 K we find d (ln R)/dp ≃ -0.12 and -0.09 GPa-1, respectively, with no systematic dependence on initial density. For 1-2-4, dTC/dp ≃ 5.1 K/GPa, which is ten times that of 1-2-3.
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| 8. |
- Andersson, Britt M., et al.
(författare)
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Thermal conductivity and thermal diffusivity of dense, bulk YBa2Cu4O8
- 1994
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Ingår i: High Temperatures - High Pressures volume 26, issue 1. - London : Pion Press. ; , s. 53-57
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Konferensbidrag (refereegranskat)abstract
- We have measured the thermal conductivity, lambda, and the thermal diffusivity, a, of dense bulk ceramic YBa2Cu4O8 (1-2-4) between 30 and 300 K. For this material lambda is about 10 W/Km near 100 K, comparable with the in-plane thermal conductivity for single crystals of the more common high-Tc material YBa2Cu3O7 (1-2-3). Also, lambda has a much stronger T dependence in 1-2-4 than in 1-2-3. We find that, for 1-2-4, lambda can be very well described by a semiclassical phonon theory, which includes phonon, electron, and boundary scattering. The difference between the present results and those for 1-2-3 can be explained mainly in terms of a smaller amount of point-defect scattering in 1-2-4 because of the stable oxygen stoichiometry of this material.
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| 9. |
- Andersson, Britt M., et al.
(författare)
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Thermal conductivity of polycrystalline YBa2Cu4O8
- 1994
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Ingår i: Physical Review B. Condensed Matter and Materials Physics. - 1098-0121 .- 1550-235X. ; 49:6, s. 4189-4198
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Tidskriftsartikel (refereegranskat)abstract
- We have measured the thermal conductivity κ and the thermal diffusivity a of a dense bulk ceramic polycrystalline sample of YBa2Cu4O8 (1:2:4) in the temperature range 30–300 K. We find κ≊10 W m-1 K-1 at 100 K, significantly higher than in ceramic YBa2Cu3O7-δ (1:2:3) and approaching the in-plane value for single-crystal 1:2:3, and decreasing to 7.6 W m-1 K-1 at 300 K. The data for this sample can be described by standard theories for phonon thermal conductivity of crystalline materials with boundary, phonon, and electron scattering. The higher κ in 1:2:4 as compared to 1:2:3 is, in this model, due to the smaller point defect scattering in the former. The fitted parameters for the three scattering mechanisms all agree with independent estimates based on simple models; inserting data for electric resistivity, grain size, carrier density, and lattice properties we can predict κ and its T dependence to within about 20%. We also discuss models for the phonon and electron thermal conductivities in some detail, including some second-order effects such as inelastic electron scattering and a T-dependent carrier density.
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| 10. |
- Andersson, Britt M., et al.
(författare)
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Thermal conductivity of YBa2Cu4O8 dominated by phonon-phonon interactions
- 1993
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Ingår i: Physical Review B. Condensed Matter and Materials Physics. - 1098-0121 .- 1550-235X. ; 48:5, s. 3575-3578
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Tidskriftsartikel (refereegranskat)abstract
- The thermal conductivity κ of dense sintered ceramic YBa2Cu4O8 in the range 30–310 K has been measured. At 100 K, κ is 10 W m-1 K-1, approaching the in-plane κ of single crystals of other high-Tc materials. κ decreases rapidly with increasing T to 7.4 W m-1 K-1 at 300 K. Fitting standard models for κ(T) to the data we find that κ is limited mainly by phonon-phonon interactions. Depending on the model used, the best fit is found for effective values of FTHETADebye between 155 and 185 K, characteristic for the acoustic phonon branches, indicating that such phonons carry most of the heat. Finally, we suggest a possible way to test the electron-phonon model for the electrical and thermal conductivities in high-Tc materials.
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| 11. |
- Andersson, Britt M., et al.
(författare)
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Thermal conductivity of YBa2Cu4O8 under high pressure
- 1993
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Ingår i: Physica. C, Superconductivity. - : Elsevier B.V.. - 0921-4534 .- 1873-2143. ; 216:1-2, s. 187-194
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Tidskriftsartikel (refereegranskat)abstract
- The thermal diffusivity a of YBa2Cu4O8 (1-2-4) has been measured as a function of pressure p and temperature T over the range 85
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| 12. |
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| 13. |
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| 14. |
- Niska, John, et al.
(författare)
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Formation of the 124 phase superconductor (YBa2Cu4O8) by retaining oxygen in a reaction HIP sintering process
- 1990
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Ingår i: Journal of materials science letters. - 0261-8028 .- 1573-4811. ; 9:7, s. 770-771
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Tidskriftsartikel (refereegranskat)abstract
- The ceramic superconductor YBa2Cu4O8 has been produced by high temperature sintering of a mixture of CuO and YBa2Cu3O7 in a glass capsule under high hydrostatic argon pressure. The resulting highly dense material is investigated by X-ray diffraction, optical and electron microscopy, resistance measurements and hardness measurements, and shown to be a homogeneous High transition temperature superconductor.
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| 15. |
- Sundqvist, Bertil, et al.
(författare)
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Constant-pressure versus constant-volume resistivities of some high transition temperature superconductors
- 1994
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Ingår i: Physica C, volume 235-240. - : Elsevier Science B.V.. ; , s. 1407-1408
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Konferensbidrag (refereegranskat)abstract
- The resistivity varrho is always measured at constant p, while theory assumes constant V. For high temperature superconductors there are large differences between constant-p and constant-V resistivities. We have previously shown constant-V results for YBa2Cu3O7−δ and show here similar data for La2−xSrxCuO4. Constant-V data for varrho agree with the behaviour expected for a normal metal, with low-T linearity in T and saturation at high T. We speculate that similar effects will be observed in doped fullerenes (M3C60, M = Li, K, Rb, …).
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| 16. |
- Sundqvist, Bertil, et al.
(författare)
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Resistivity of high-Tc superconductors: Linear in T at constant p, non-linear at constant V
- 1990
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Ingår i: Solid State Communications. - : Elsevier Science Ltd. - 0038-1098 .- 1879-2766. ; 76:8, s. 1019-1022
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Tidskriftsartikel (refereegranskat)abstract
- The observed constant-pressure resistivity varrhop of most high-Tc superconductors is linear in temperature T over large ranges. We show that this is not true for the constant-volume resistivity varrhov; for 1–2–3 YBCO the correction from varrhop to varrhov is -32% at 500 K relative to the low-T value. Since theory predicts varrhov rather than varrhop, the observed linearity of varrho probably cannot be used as a tool to choose between theories for high-Tc superconductivity.
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| 17. |
- Sundqvist, Bertil, et al.
(författare)
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Thermal conductivity of bulk YBa2Cu4O8 and the phonon transport model
- 1994
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Ingår i: Physica C, volume 235-240. - : Elsevier Science B.V.. ; , s. 1377-1378
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Konferensbidrag (refereegranskat)abstract
- We have measured the thermal conductivity varkappa of bulk YBa2Cu4O8 (1-2-4) between 30 and 310 K and at pressures p up to 1 GPa. At p = 0, varkappa = 10 Wm−1K−1 near 100 K, twice that of sintered YBa2Cu3O−δ (1-2-3). varkappa also decreases with increasing T more rapidly than in 1-2-3, to 7.4 Wm−1K−1 at 300 K. Under pressure, varkappa increases slowly with p above 150 K, but dvarkappa/dp decreases at lower T. Our results are in excellent agreement with a semi-classical model for phonon thermal conductivity, provided we assume significant charge transfer with pressure. The calculated phonon mean free path is much larger than the lattice spacing at all T.
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| 18. |
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| 19. |
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