1
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Sanchez-Manzano D, Mesoraca S, Cuellar FA, Cabero M, Rouco V, Orfila G, Palermo X, Balan A, Marcano L, Sander A, Rocci M, Garcia-Barriocanal J, Gallego F, Tornos J, Rivera A, Mompean F, Garcia-Hernandez M, Gonzalez-Calbet JM, Leon C, Valencia S, Feuillet-Palma C, Bergeal N, Buzdin AI, Lesueur J, Villegas JE, Santamaria J. Extremely long-range, high-temperature Josephson coupling across a half-metallic ferromagnet. Nat Mater 2022; 21:188-194. [PMID: 34857910 DOI: 10.1038/s41563-021-01162-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Accepted: 10/21/2021] [Indexed: 06/13/2023]
Abstract
The Josephson effect results from the coupling of two superconductors across a spacer such as an insulator, a normal metal or a ferromagnet to yield a phase coherent quantum state. However, in junctions with ferromagnetic spacers, very long-range Josephson effects have remained elusive. Here we demonstrate extremely long-range (micrometric) high-temperature (tens of kelvins) Josephson coupling across the half-metallic manganite La0.7Sr0.3MnO3 combined with the superconducting cuprate YBa2Cu3O7. These planar junctions, in addition to large critical currents, display the hallmarks of Josephson physics, such as critical current oscillations driven by magnetic flux quantization and quantum phase locking effects under microwave excitation (Shapiro steps). The latter display an anomalous doubling of the Josephson frequency predicted by several theories. In addition to its fundamental interest, the marriage between high-temperature, dissipationless quantum coherent transport and full spin polarization brings opportunities for the practical realization of superconducting spintronics, and opens new perspectives for quantum computing.
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Affiliation(s)
- D Sanchez-Manzano
- GFMC, Departamento Fisica de Materiales, Facultad de Fisica, Universidad Complutense, Madrid, Spain
| | - S Mesoraca
- Unité Mixte de Physique, CNRS, Thales, Université Paris-Saclay, Palaiseau, France
| | - F A Cuellar
- GFMC, Departamento Fisica de Materiales, Facultad de Fisica, Universidad Complutense, Madrid, Spain
| | - M Cabero
- IMDEA Nanoscience Institute, Universidad Autonoma, Cantoblanco, Spain
- Centro Nacional de Microscopia Electronica, Universidad Complutense, Madrid, Spain
| | - V Rouco
- GFMC, Departamento Fisica de Materiales, Facultad de Fisica, Universidad Complutense, Madrid, Spain
| | - G Orfila
- GFMC, Departamento Fisica de Materiales, Facultad de Fisica, Universidad Complutense, Madrid, Spain
| | - X Palermo
- Unité Mixte de Physique, CNRS, Thales, Université Paris-Saclay, Palaiseau, France
| | - A Balan
- Unité Mixte de Physique, CNRS, Thales, Université Paris-Saclay, Palaiseau, France
| | - L Marcano
- Helmholtz-Zentrum Berlin für Materialien und Energie, Berlin, Germany
| | - A Sander
- Unité Mixte de Physique, CNRS, Thales, Université Paris-Saclay, Palaiseau, France
| | - M Rocci
- GFMC, Departamento Fisica de Materiales, Facultad de Fisica, Universidad Complutense, Madrid, Spain
- Instituto Nanoscienze, Consiglio Thales Alenia Space Italia, L'Aquila, Italy
| | | | - F Gallego
- GFMC, Departamento Fisica de Materiales, Facultad de Fisica, Universidad Complutense, Madrid, Spain
| | - J Tornos
- GFMC, Departamento Fisica de Materiales, Facultad de Fisica, Universidad Complutense, Madrid, Spain
| | - A Rivera
- GFMC, Departamento Fisica de Materiales, Facultad de Fisica, Universidad Complutense, Madrid, Spain
| | - F Mompean
- Instituto de Ciencia de Materiales de Madrid (ICMM, CSIC), Cantoblanco, Spain
- Laboratorio de Heteroestructuras con Aplicación en Spintrónica, Unidad Asociada (UCM-CSIC), Madrid, Spain
| | - M Garcia-Hernandez
- Instituto de Ciencia de Materiales de Madrid (ICMM, CSIC), Cantoblanco, Spain
- Laboratorio de Heteroestructuras con Aplicación en Spintrónica, Unidad Asociada (UCM-CSIC), Madrid, Spain
| | - J M Gonzalez-Calbet
- Centro Nacional de Microscopia Electronica, Universidad Complutense, Madrid, Spain
- Departamento Química Inorgánica, Facultad de Química, Universidad Complutense, Madrid, Spain
| | - C Leon
- GFMC, Departamento Fisica de Materiales, Facultad de Fisica, Universidad Complutense, Madrid, Spain
| | - S Valencia
- Helmholtz-Zentrum Berlin für Materialien und Energie, Berlin, Germany
| | - C Feuillet-Palma
- Laboratoire de Physique et d'Etude des Matériaux, ESPCI Paris, CNRS, PSL Research University, Sorbonne University, Paris, France
| | - N Bergeal
- Laboratoire de Physique et d'Etude des Matériaux, ESPCI Paris, CNRS, PSL Research University, Sorbonne University, Paris, France
| | - A I Buzdin
- LOMA, CNRS, Université Bordeaux, Talence, France
- Digital Biodesign and Personalized Healthcare, Sechenov First Moscow State Medical University, Moscow, Russia
| | - J Lesueur
- Laboratoire de Physique et d'Etude des Matériaux, ESPCI Paris, CNRS, PSL Research University, Sorbonne University, Paris, France
| | - Javier E Villegas
- Unité Mixte de Physique, CNRS, Thales, Université Paris-Saclay, Palaiseau, France.
| | - J Santamaria
- GFMC, Departamento Fisica de Materiales, Facultad de Fisica, Universidad Complutense, Madrid, Spain.
- Laboratorio de Heteroestructuras con Aplicación en Spintrónica, Unidad Asociada (UCM-CSIC), Madrid, Spain.
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2
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Arias-Egido E, Laguna-Marco MA, Piquer C, Jiménez-Cavero P, Lucas I, Morellón L, Gallego F, Rivera-Calzada A, Cabero-Piris M, Santamaria J, Fabbris G, Haskel D, Boada R, Díaz-Moreno S. Dimensionality-driven metal-insulator transition in spin-orbit-coupled IrO 2. Nanoscale 2021; 13:17125-17135. [PMID: 34635906 DOI: 10.1039/d1nr04207f] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
A metal-insulator transition is observed in spin-orbit-coupled IrO2 thin films upon reduction of the film thickness. In the epitaxially grown samples, the critical thickness (t ∼ 1.5-2.2 nm) is found to depend on growth orientation (001), (100) or (110). Interestingly from the applied point of view, the insulating behavior is found even in polycrystalline ultrathin films. By analyzing the experimental electrical response with various theoretical models, we find good fits to the Efros-Shklovskii-VRH and the Arrhenius-type behaviors, which suggests an important role of electron correlations in determining the electrical properties of IrO2. Our magnetic measurements also point to a significant role of magnetic order. Altogether, our results would point to a mixed Slater- and Mott-type of insulator.
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Affiliation(s)
- E Arias-Egido
- Instituto de Nanociencia y Materiales de Aragón (INMA), CSIC - Universidad de Zaragoza, Zaragoza 50009, Spain.
- Departamento de Física de la Materia Condensada, Universidad de Zaragoza, Zaragoza 50009, Spain
| | - M A Laguna-Marco
- Instituto de Nanociencia y Materiales de Aragón (INMA), CSIC - Universidad de Zaragoza, Zaragoza 50009, Spain.
- Departamento de Física de la Materia Condensada, Universidad de Zaragoza, Zaragoza 50009, Spain
- Instituto de Ciencia de Materiales de Madrid, CSIC, Cantoblanco, 28049 Madrid, Spain
| | - C Piquer
- Instituto de Nanociencia y Materiales de Aragón (INMA), CSIC - Universidad de Zaragoza, Zaragoza 50009, Spain.
- Departamento de Física de la Materia Condensada, Universidad de Zaragoza, Zaragoza 50009, Spain
| | - P Jiménez-Cavero
- Instituto de Nanociencia y Materiales de Aragón (INMA), CSIC - Universidad de Zaragoza, Zaragoza 50009, Spain.
- Departamento de Física de la Materia Condensada, Universidad de Zaragoza, Zaragoza 50009, Spain
| | - I Lucas
- Instituto de Nanociencia y Materiales de Aragón (INMA), CSIC - Universidad de Zaragoza, Zaragoza 50009, Spain.
- Departamento de Física de la Materia Condensada, Universidad de Zaragoza, Zaragoza 50009, Spain
| | - L Morellón
- Instituto de Nanociencia y Materiales de Aragón (INMA), CSIC - Universidad de Zaragoza, Zaragoza 50009, Spain.
- Departamento de Física de la Materia Condensada, Universidad de Zaragoza, Zaragoza 50009, Spain
| | - F Gallego
- GFMC, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | | | - M Cabero-Piris
- ICTS - Centro Nacional de Microscopía Electrónica, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | - J Santamaria
- GFMC, Universidad Complutense de Madrid, 28040 Madrid, Spain
- Laboratorio de Heteroestructuras con aplicación en spintrónica, Unidad Asociada UCM/CSIC, 28049 Madrid, Spain
- GFMC, Instituto de Magnetismo Aplicado, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | - G Fabbris
- Advanced Photon Source, Argonne National Laboratory, Argonne, IL 60439, USA
| | - D Haskel
- Advanced Photon Source, Argonne National Laboratory, Argonne, IL 60439, USA
| | - R Boada
- Department of Chemistry Universitat Autonoma de Barcelona 08193 Bellaterra, Barcelona, Spain
- Diamond Light Source Ltd Harwell Science and Innovation Campus Didcot, Oxfordshire OX11 0DE, UK
| | - S Díaz-Moreno
- Diamond Light Source Ltd Harwell Science and Innovation Campus Didcot, Oxfordshire OX11 0DE, UK
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3
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Yoo MW, Tornos J, Sander A, Lin LF, Mohanta N, Peralta A, Sanchez-Manzano D, Gallego F, Haskel D, Freeland JW, Keavney DJ, Choi Y, Strempfer J, Wang X, Cabero M, Vasili HB, Valvidares M, Sanchez-Santolino G, Gonzalez-Calbet JM, Rivera A, Leon C, Rosenkranz S, Bibes M, Barthelemy A, Anane A, Dagotto E, Okamoto S, te Velthuis SGE, Santamaria J, Villegas JE. Large intrinsic anomalous Hall effect in SrIrO 3 induced by magnetic proximity effect. Nat Commun 2021; 12:3283. [PMID: 34078889 PMCID: PMC8172877 DOI: 10.1038/s41467-021-23489-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Accepted: 04/25/2021] [Indexed: 02/04/2023] Open
Abstract
The anomalous Hall effect (AHE) is an intriguing transport phenomenon occurring typically in ferromagnets as a consequence of broken time reversal symmetry and spin-orbit interaction. It can be caused by two microscopically distinct mechanisms, namely, by skew or side-jump scattering due to chiral features of the disorder scattering, or by an intrinsic contribution directly linked to the topological properties of the Bloch states. Here we show that the AHE can be artificially engineered in materials in which it is originally absent by combining the effects of symmetry breaking, spin orbit interaction and proximity-induced magnetism. In particular, we find a strikingly large AHE that emerges at the interface between a ferromagnetic manganite (La0.7Sr0.3MnO3) and a semimetallic iridate (SrIrO3). It is intrinsic and originates in the proximity-induced magnetism present in the narrow bands of strong spin-orbit coupling material SrIrO3, which yields values of anomalous Hall conductivity and Hall angle as high as those observed in bulk transition-metal ferromagnets. These results demonstrate the interplay between correlated electron physics and topological phenomena at interfaces between 3d ferromagnets and strong spin-orbit coupling 5d oxides and trace an exciting path towards future topological spintronics at oxide interfaces.
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Affiliation(s)
- Myoung-Woo Yoo
- grid.460789.40000 0004 4910 6535Unité Mixte de Physique, CNRS, Thales, Université Paris-Saclay, Palaiseau, France
| | - J. Tornos
- grid.4795.f0000 0001 2157 7667GFMC, Dept. Fisica de Materiales, Facultad de Fisica, Universidad Complutense, Madrid, Spain
| | - A. Sander
- grid.460789.40000 0004 4910 6535Unité Mixte de Physique, CNRS, Thales, Université Paris-Saclay, Palaiseau, France
| | - Ling-Fang Lin
- grid.411461.70000 0001 2315 1184Department of Physics and Astronomy, University of Tennessee, Knoxville, TN USA ,grid.263826.b0000 0004 1761 0489School of Physics, Southeast University, Nanjing, China
| | - Narayan Mohanta
- grid.135519.a0000 0004 0446 2659Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN USA
| | - A. Peralta
- grid.4795.f0000 0001 2157 7667GFMC, Dept. Fisica de Materiales, Facultad de Fisica, Universidad Complutense, Madrid, Spain
| | - D. Sanchez-Manzano
- grid.4795.f0000 0001 2157 7667GFMC, Dept. Fisica de Materiales, Facultad de Fisica, Universidad Complutense, Madrid, Spain
| | - F. Gallego
- grid.4795.f0000 0001 2157 7667GFMC, Dept. Fisica de Materiales, Facultad de Fisica, Universidad Complutense, Madrid, Spain
| | - D. Haskel
- grid.187073.a0000 0001 1939 4845Advanced Photon Source Argonne National Laboratory, Lemont, IL USA
| | - J. W. Freeland
- grid.187073.a0000 0001 1939 4845Advanced Photon Source Argonne National Laboratory, Lemont, IL USA
| | - D. J. Keavney
- grid.187073.a0000 0001 1939 4845Advanced Photon Source Argonne National Laboratory, Lemont, IL USA
| | - Y. Choi
- grid.187073.a0000 0001 1939 4845Advanced Photon Source Argonne National Laboratory, Lemont, IL USA
| | - J. Strempfer
- grid.187073.a0000 0001 1939 4845Advanced Photon Source Argonne National Laboratory, Lemont, IL USA
| | - X. Wang
- grid.253355.70000 0001 2192 5641Department of Physics, Bryn Mawr College, Bryn Mawr, PA USA
| | - M. Cabero
- grid.5515.40000000119578126IMDEA Nanoscience Campus Universidad Autonoma, Cantoblanco, Spain ,grid.4795.f0000 0001 2157 7667Centro Nacional de Microscopia Electronica, Universidad Complutense, Madrid, Spain
| | - Hari Babu Vasili
- grid.423639.9CELLS-ALBA Synchrotron Radiation Facility, Cerdanyola del Valles, Spain
| | - Manuel Valvidares
- grid.423639.9CELLS-ALBA Synchrotron Radiation Facility, Cerdanyola del Valles, Spain
| | - G. Sanchez-Santolino
- grid.4795.f0000 0001 2157 7667GFMC, Dept. Fisica de Materiales, Facultad de Fisica, Universidad Complutense, Madrid, Spain
| | - J. M. Gonzalez-Calbet
- grid.4795.f0000 0001 2157 7667Centro Nacional de Microscopia Electronica, Universidad Complutense, Madrid, Spain ,grid.4795.f0000 0001 2157 7667Department Quimica Inorganica, Facultad de Quimica, Universidad Complutense, Madrid, Spain
| | - A. Rivera
- grid.4795.f0000 0001 2157 7667GFMC, Dept. Fisica de Materiales, Facultad de Fisica, Universidad Complutense, Madrid, Spain
| | - C. Leon
- grid.4795.f0000 0001 2157 7667GFMC, Dept. Fisica de Materiales, Facultad de Fisica, Universidad Complutense, Madrid, Spain
| | - S. Rosenkranz
- grid.187073.a0000 0001 1939 4845Materials Science Division, Argonne National Laboratory, Lemont, IL USA
| | - M. Bibes
- grid.460789.40000 0004 4910 6535Unité Mixte de Physique, CNRS, Thales, Université Paris-Saclay, Palaiseau, France
| | - A. Barthelemy
- grid.460789.40000 0004 4910 6535Unité Mixte de Physique, CNRS, Thales, Université Paris-Saclay, Palaiseau, France
| | - A. Anane
- grid.460789.40000 0004 4910 6535Unité Mixte de Physique, CNRS, Thales, Université Paris-Saclay, Palaiseau, France
| | - Elbio Dagotto
- grid.411461.70000 0001 2315 1184Department of Physics and Astronomy, University of Tennessee, Knoxville, TN USA ,grid.135519.a0000 0004 0446 2659Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN USA
| | - S. Okamoto
- grid.135519.a0000 0004 0446 2659Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN USA
| | - S. G. E. te Velthuis
- grid.187073.a0000 0001 1939 4845Materials Science Division, Argonne National Laboratory, Lemont, IL USA
| | - J. Santamaria
- grid.4795.f0000 0001 2157 7667GFMC, Dept. Fisica de Materiales, Facultad de Fisica, Universidad Complutense, Madrid, Spain
| | - Javier E. Villegas
- grid.460789.40000 0004 4910 6535Unité Mixte de Physique, CNRS, Thales, Université Paris-Saclay, Palaiseau, France
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4
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Hernandez-Martin D, Gallego F, Tornos J, Rouco V, Beltran JI, Munuera C, Sanchez-Manzano D, Cabero M, Cuellar F, Arias D, Sanchez-Santolino G, Mompean FJ, Garcia-Hernandez M, Rivera-Calzada A, Pennycook SJ, Varela M, Muñoz MC, Sefrioui Z, Leon C, Santamaria J. Controlled Sign Reversal of Electroresistance in Oxide Tunnel Junctions by Electrochemical-Ferroelectric Coupling. Phys Rev Lett 2020; 125:266802. [PMID: 33449729 DOI: 10.1103/physrevlett.125.266802] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Accepted: 11/24/2020] [Indexed: 06/12/2023]
Abstract
The persistence of ferroelectricity in ultrathin layers relies critically on screening or compensation of polarization charges which otherwise destabilize the ferroelectric state. At surfaces, charged defects play a crucial role in the screening mechanism triggering novel mixed electrochemical-ferroelectric states. At interfaces, however, the coupling between ferroelectric and electrochemical states has remained unexplored. Here, we make use of the dynamic formation of the oxygen vacancy profile in the nanometer-thick barrier of a ferroelectric tunnel junction to demonstrate the interplay between electrochemical and ferroelectric degrees of freedom at an oxide interface. We fabricate ferroelectric tunnel junctions with a La_{0.7}Sr_{0.3}MnO_{3} bottom electrode and BaTiO_{3} ferroelectric barrier. We use poling strategies to promote the generation and transport of oxygen vacancies at the metallic top electrode. Generated oxygen vacancies control the stability of the ferroelectric polarization and modify its coercive fields. The ferroelectric polarization, in turn, controls the ionization of oxygen vacancies well above the limits of thermodynamic equilibrium, triggering the build up of a Schottky barrier at the interface which can be turned on and off with ferroelectric switching. This interplay between electronic and electrochemical degrees of freedom yields very large values of the electroresistance (more than 10^{6}% at low temperatures) and enables a controlled switching between clockwise and counterclockwise switching modes in the same junction (and consequently, a change of the sign of the electroresistance). The strong coupling found between electrochemical and electronic degrees of freedom sheds light on the growing debate between resistive and ferroelectric switching in ferroelectric tunnel junctions, and moreover, can be the source of novel concepts in memory devices and neuromorphic computing.
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Affiliation(s)
| | - F Gallego
- GFMC, Universidad Complutense de Madrid, 28040 Madrid, Spain
- 2D-Foundry Group, Instituto de Ciencia de Materiales de Madrid ICMM-CSIC, 28049 Madrid, Spain
| | - J Tornos
- GFMC, Universidad Complutense de Madrid, 28040 Madrid, Spain
- 2D-Foundry Group, Instituto de Ciencia de Materiales de Madrid ICMM-CSIC, 28049 Madrid, Spain
| | - V Rouco
- GFMC, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | - J I Beltran
- GFMC, Universidad Complutense de Madrid, 28040 Madrid, Spain
- Instituto Pluridisciplinar, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | - C Munuera
- 2D-Foundry Group, Instituto de Ciencia de Materiales de Madrid ICMM-CSIC, 28049 Madrid, Spain
- Unidad Asociada UCM/CSIC, Laboratorio de Heteroestructuras con Aplicación en Spintrónica, 28049 Madrid, Spain
| | | | - M Cabero
- GFMC, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | - F Cuellar
- GFMC, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | - D Arias
- GFMC, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | - G Sanchez-Santolino
- GFMC, Universidad Complutense de Madrid, 28040 Madrid, Spain
- 2D-Foundry Group, Instituto de Ciencia de Materiales de Madrid ICMM-CSIC, 28049 Madrid, Spain
- Instituto Pluridisciplinar, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | - F J Mompean
- 2D-Foundry Group, Instituto de Ciencia de Materiales de Madrid ICMM-CSIC, 28049 Madrid, Spain
- Unidad Asociada UCM/CSIC, Laboratorio de Heteroestructuras con Aplicación en Spintrónica, 28049 Madrid, Spain
| | - M Garcia-Hernandez
- 2D-Foundry Group, Instituto de Ciencia de Materiales de Madrid ICMM-CSIC, 28049 Madrid, Spain
- Unidad Asociada UCM/CSIC, Laboratorio de Heteroestructuras con Aplicación en Spintrónica, 28049 Madrid, Spain
| | - A Rivera-Calzada
- GFMC, Universidad Complutense de Madrid, 28040 Madrid, Spain
- Unidad Asociada UCM/CSIC, Laboratorio de Heteroestructuras con Aplicación en Spintrónica, 28049 Madrid, Spain
| | - S J Pennycook
- Department of Materials Science & Engineering, National University of Singapore, Singapore 117575
| | - M Varela
- GFMC, Universidad Complutense de Madrid, 28040 Madrid, Spain
- Instituto Pluridisciplinar, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | - M C Muñoz
- Unidad Asociada UCM/CSIC, Laboratorio de Heteroestructuras con Aplicación en Spintrónica, 28049 Madrid, Spain
- Instituto de Ciencia de Materiales de Madrid ICMM-CSIC, 28049 Madrid, Spain
| | - Z Sefrioui
- GFMC, Universidad Complutense de Madrid, 28040 Madrid, Spain
- Unidad Asociada UCM/CSIC, Laboratorio de Heteroestructuras con Aplicación en Spintrónica, 28049 Madrid, Spain
- GFMC, Instituto de Magnetismo Aplicado, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | - C Leon
- GFMC, Universidad Complutense de Madrid, 28040 Madrid, Spain
- Unidad Asociada UCM/CSIC, Laboratorio de Heteroestructuras con Aplicación en Spintrónica, 28049 Madrid, Spain
- GFMC, Instituto de Magnetismo Aplicado, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | - J Santamaria
- GFMC, Universidad Complutense de Madrid, 28040 Madrid, Spain
- Unidad Asociada UCM/CSIC, Laboratorio de Heteroestructuras con Aplicación en Spintrónica, 28049 Madrid, Spain
- GFMC, Instituto de Magnetismo Aplicado, Universidad Complutense de Madrid, 28040 Madrid, Spain
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5
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Tornos J, Gallego F, Valencia S, Liu YH, Rouco V, Lauter V, Abrudan R, Luo C, Ryll H, Wang Q, Hernandez-Martin D, Orfila G, Cabero M, Cuellar F, Arias D, Mompean FJ, Garcia-Hernandez M, Radu F, Charlton TR, Rivera-Calzada A, Sefrioui Z, Te Velthuis SGE, Leon C, Santamaria J. Ferroelectric Control of Interface Spin Filtering in Multiferroic Tunnel Junctions. Phys Rev Lett 2019; 122:037601. [PMID: 30735408 DOI: 10.1103/physrevlett.122.037601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2018] [Revised: 07/27/2018] [Indexed: 06/09/2023]
Abstract
The electronic reconstruction occurring at oxide interfaces may be the source of interesting device concepts for future oxide electronics. Among oxide devices, multiferroic tunnel junctions are being actively investigated as they offer the possibility to modulate the junction current by independently controlling the switching of the magnetization of the electrodes and of the ferroelectric polarization of the barrier. In this Letter, we show that the spin reconstruction at the interfaces of a La_{0.7}Sr_{0.3}MnO_{3}/BaTiO_{3}/La_{0.7}Sr_{0.3}MnO_{3} multiferroic tunnel junction is the origin of a spin filtering functionality that can be turned on and off by reversing the ferroelectric polarization. The ferroelectrically controlled interface spin filter enables a giant electrical modulation of the tunneling magnetoresistance between values of 10% and 1000%, which could inspire device concepts in oxides-based low dissipation spintronics.
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Affiliation(s)
- J Tornos
- GFMC, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | - F Gallego
- GFMC, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | - S Valencia
- Hemholtz-Zentrum Berlin für Materialen und Energie, Albert-Einstein-Strasse 15, 12489 Berlin, Germany
| | - Y H Liu
- Oak Ridge National Laboratory, Neutron Scattering Division, Oak Ridge, Tennessee 37831, USA
- Argonne National Laboratory, Materials Science Division, Argonne, Illinois 60439, USA
| | - V Rouco
- Unité Mixte de Physique, CNRS, Thales, Université Paris-Saclay, 91767 Palaiseau, France
| | - V Lauter
- Oak Ridge National Laboratory, Neutron Scattering Division, Oak Ridge, Tennessee 37831, USA
| | - R Abrudan
- Hemholtz-Zentrum Berlin für Materialen und Energie, Albert-Einstein-Strasse 15, 12489 Berlin, Germany
- Institut für Experimentalphysik (Festkörperphysik), Ruhr-Universität Bochum, 44780 Bochum, Germany
| | - C Luo
- Hemholtz-Zentrum Berlin für Materialen und Energie, Albert-Einstein-Strasse 15, 12489 Berlin, Germany
- University of Regensburg, Universitätsstrasse 31, 93053 Regensburg, Germany
| | - H Ryll
- Hemholtz-Zentrum Berlin für Materialen und Energie, Albert-Einstein-Strasse 15, 12489 Berlin, Germany
| | - Q Wang
- Argonne National Laboratory, Materials Science Division, Argonne, Illinois 60439, USA
| | | | - G Orfila
- GFMC, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | - M Cabero
- GFMC, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | - F Cuellar
- GFMC, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | - D Arias
- GFMC, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | - F J Mompean
- 2D-Foundry Group, Instituto de Ciencia de Materiales de Madrid ICMM-CSIC, 28049 Madrid, Spain
- Laboratorio de Heteroestructuras con aplicación en spintrónica, Unidad Asociada UCM/CSIC, 28049 Madrid, Spain
| | - M Garcia-Hernandez
- 2D-Foundry Group, Instituto de Ciencia de Materiales de Madrid ICMM-CSIC, 28049 Madrid, Spain
- Laboratorio de Heteroestructuras con aplicación en spintrónica, Unidad Asociada UCM/CSIC, 28049 Madrid, Spain
| | - F Radu
- Hemholtz-Zentrum Berlin für Materialen und Energie, Albert-Einstein-Strasse 15, 12489 Berlin, Germany
| | - T R Charlton
- ISIS, Rutherford Appleton Laboratory, Chilton, Oxon OX11 0QX, United Kingdom
| | - A Rivera-Calzada
- GFMC, Universidad Complutense de Madrid, 28040 Madrid, Spain
- Laboratorio de Heteroestructuras con aplicación en spintrónica, Unidad Asociada UCM/CSIC, 28049 Madrid, Spain
| | - Z Sefrioui
- GFMC, Universidad Complutense de Madrid, 28040 Madrid, Spain
- Laboratorio de Heteroestructuras con aplicación en spintrónica, Unidad Asociada UCM/CSIC, 28049 Madrid, Spain
- GFMC, Instituto de Magnetismo Aplicado, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | - S G E Te Velthuis
- Argonne National Laboratory, Materials Science Division, Argonne, Illinois 60439, USA
| | - C Leon
- GFMC, Universidad Complutense de Madrid, 28040 Madrid, Spain
- Laboratorio de Heteroestructuras con aplicación en spintrónica, Unidad Asociada UCM/CSIC, 28049 Madrid, Spain
- GFMC, Instituto de Magnetismo Aplicado, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | - J Santamaria
- GFMC, Universidad Complutense de Madrid, 28040 Madrid, Spain
- Laboratorio de Heteroestructuras con aplicación en spintrónica, Unidad Asociada UCM/CSIC, 28049 Madrid, Spain
- GFMC, Instituto de Magnetismo Aplicado, Universidad Complutense de Madrid, 28040 Madrid, Spain
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6
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Salas J, Díez F, Puerta J, Zambrana JL, Delgado M, Rivera F, Gallego F. [Current census rates in inpatients hospitalized in the Hospital de Poniente in Almería [Spain]]. Gac Sanit 2003; 17:312-5. [PMID: 12975056 DOI: 10.1016/s0213-9111(03)71753-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
OBJECTIVE To study the current census rate of patients admitted to an internal medicine service. METHOD We studied all patients admitted to the internal medicine service from January 1 to August 31, 2000 whose addresses were registered in four local authorities of our hospital district. We made exhaustive searches to ascertain whether these patients were included in the register in September 2000. RESULTS We analyzed 1,095 admissions from a total of 1,759 up to August 31, 2000. Twenty-four percent corresponded to patients who were not registered. Fifty-eight percent of those not registered were aged more than 70 years. Twenty-seven percent of patients aged less than 40 years, most of whom were immigrants, were also unregistered. CONCLUSIONS Twenty-four percent of the admissions to the internal medicine service that were studied corresponded to patients who were not registered with their respective local authorities. A possible explanation is the large immigrant population and the lack of registration among the elderly.
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Affiliation(s)
- J Salas
- Servicio de Medicina Interna.Hospital de Poniente. El Ejido. Almería. Spain.
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7
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Rodríguez-Concepción M, Ahumada I, Diez-Juez E, Sauret-Güeto S, Lois LM, Gallego F, Carretero-Paulet L, Campos N, Boronat A. 1-Deoxy-D-xylulose 5-phosphate reductoisomerase and plastid isoprenoid biosynthesis during tomato fruit ripening. Plant J 2001; 27:213-22. [PMID: 11532167 DOI: 10.1046/j.1365-313x.2001.01089.x] [Citation(s) in RCA: 91] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
The recently discovered 2-C-methyl-D-erythritol 4-phosphate (MEP) pathway for the biosynthesis of plastid isoprenoids (including carotenoids) is not fully elucidated yet despite its central importance for plant life. It is known, however, that the first reaction completely specific to the pathway is the conversion of 1-deoxy-D-xylulose 5-phosphate (DXP) into MEP by the enzyme DXP reductoisomerase (DXR). We have identified a tomato cDNA encoding a protein with homology to DXR and in vivo activity, and show that the levels of the corresponding DXR mRNA and encoded protein in fruit tissues are similar before and during the massive accumulation of carotenoids characteristic of fruit ripening. The results are consistent with a non-limiting role of DXR, and support previous work proposing DXP synthase (DXS) as the first regulatory enzyme for plastid isoprenoid biosynthesis in tomato fruit. Inhibition of DXR activity by fosmidomycin showed that plastid isoprenoid biosynthesis is required for tomato fruit carotenogenesis but not for other ripening processes. In addition, dormancy was reduced in seeds from fosmidomycin-treated fruit but not in seeds from the tomato yellow ripe mutant (defective in phytoene synthase-1, PSY1), suggesting that the isoform PSY2 might channel the production of carotenoids for abscisic acid biosynthesis. Furthermore, the complete arrest of tomato seedling development using fosmidomycin confirms a key role of the MEP pathway in plant development.
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Affiliation(s)
- M Rodríguez-Concepción
- Departament de Bioquímica i Biologia Molecular, Facultat de Química, Universitat de Barcelona, Martí i Franquès 1-7, 08028 Barcelona, Spain.
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8
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Campos N, Rodríguez-Concepción M, Sauret-Güeto S, Gallego F, Lois LM, Boronat A. Escherichia coli engineered to synthesize isopentenyl diphosphate and dimethylallyl diphosphate from mevalonate: a novel system for the genetic analysis of the 2-C-methyl-d-erythritol 4-phosphate pathway for isoprenoid biosynthesis. Biochem J 2001; 353:59-67. [PMID: 11115399 PMCID: PMC1221543] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
Isopentenyl diphosphate (IPP) and its isomer dimethylallyl diphosphate (DMAPP) constitute the basic building block of isoprenoids, a family of compounds that is extraordinarily diverse in structure and function. IPP and DMAPP can be synthesized by two independent pathways: the mevalonate pathway and the recently discovered 2-C-methyl-d-erythritol 4-phosphate (MEP) pathway. Although the MEP pathway is essential in most eubacteria, algae and plants and has enormous biotechnological interest, only some of its steps have been determined. We devised a system suitable for the genetic analysis of the MEP pathway in Escherichia coli. A synthetic operon coding for yeast 5-diphosphomevalonate decarboxylase, human 5-phosphomevalonate kinase, yeast mevalonate kinase and E. coli isopentenyl diphosphate isomerase was incorporated in the chromosome of this bacterium. The expression of this operon allowed the synthesis of IPP and DMAPP from mevalonate added exogenously and complementation of lethal mutants of the MEP pathway. We used this system to show that the ygbP, ychB and ygbB genes are essential in E. coli and that the steps catalysed by the products of these genes belong to the trunk line of the MEP pathway.
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Affiliation(s)
- N Campos
- Department de Bioquímica i Biologia Molecular, Facultat de Química, Universitat de Barcelona, C/Martí i Franquès 1, 08028 Barcelona, Spain.
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9
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Lois LM, Rodríguez-Concepción M, Gallego F, Campos N, Boronat A. Carotenoid biosynthesis during tomato fruit development: regulatory role of 1-deoxy-D-xylulose 5-phosphate synthase. Plant J 2000; 22:503-13. [PMID: 10886770 DOI: 10.1046/j.1365-313x.2000.00764.x] [Citation(s) in RCA: 248] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Plant isoprenoids represent a heterogeneous group of compounds which play essential roles not only in growth and development, but also in the interaction of plants with their environment. Higher plants contain two pathways for the biosynthesis of isoprenoids: the mevalonate pathway, located in the cytosol/endoplasmic reticulum, and the recently discovered mevalonate-independent pathway (Rohmer pathway), located in the plastids. In order to evaluate the function of the Rohmer pathway in the regulation of the synthesis of plastidial isoprenoids, we have isolated a tomato cDNA encoding 1-deoxy-D-xylulose 5-phosphate synthase (DXS), the first enzyme of the pathway. We demonstrate in vivo activity and plastid targeting of plant DXS. Expression analysis of the tomato DXS gene indicates developmental and organ-specific regulation of mRNA accumulation and a strong correlation with carotenoid synthesis during fruit development. 1-Deoxy-D-xylulose feeding experiments, together with expression analysis of DXS and PSY1 (encoding the fruit-specific isoform of phytoene synthase) in wild-type and yellow flesh mutant fruits, indicate that DXS catalyses the first potentially regulatory step in carotenoid biosynthesis during early fruit ripening. Our results change the current view that PSY1 is the only regulatory enzyme in tomato fruit carotenogenesis, and point towards a coordinated role of both DXS and PSY1 in the control of fruit carotenoid synthesis.
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Affiliation(s)
- L M Lois
- Departament de Bioquímica i Biologia Molecular, Facultat de Química, Universitat de Barcelona, Barcelona, Spain
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10
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López-Contreras J, Blanco-Vaca F, Borrás X, Carreras F, Pons-Lladó G, Gallego F, Solé MJ, Cirera S, Benet MT, Negredo E, Roca-Cusachs A. Usefulness of the I/D angiotensin-converting enzyme genotype for detecting the risk of left ventricular hypertrophy in pharmacologically treated hypertensive men. J Hum Hypertens 2000; 14:327-31. [PMID: 10822320 DOI: 10.1038/sj.jhh.1001005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The insertion/deletion polymorphism (I/D) of the angiotensin-converting enzyme (ACE) gene has been associated in some studies with a higher prevalence of left ventricular hypertrophy (LVH), but few of them were performed on pharmacologically treated hypertensive patients. The present study was undertaken to determine whether ACE genotype determination could help in the identification of pharmacologically treated hypertensive patients at a higher risk of LVH. Ninety-six consecutive men with essential hypertension were selected for the study. Left ventricular mass (LVM) was assessed by echocardiography and indexed by body surface area and 82 patients were considered suitable for the study. Three groups of patients were defined on the basis of their I/D ACE genotype: DD (n = 39), ID (n = 33) and II (n = 10). There were no statistically significant differences between the three groups regarding to the severity of hypertension at diagnosis, degree of control of blood pressure or type of antihypertensive drug therapy used. No statistically significant differences were found between the three groups regarding to LVM index (total 124 +/- 31, DD 121 +/- 29, ID 127 +/- 35 and II 122 +/- 18 g/m2), relative wall thickness (total 0.5 +/- 0. 2, DD 0.5 +/- 0.3, ID 0.48 +/- 0.07 and II 0.47 +/- 0.04) or prevalence of LVH (total 34%, DD 31%, ID 39% and II 30% by Cornell criteria and total 39%, DD 33%, ID 45% and II 40% by Framingham criteria). Furthermore, the I and D allele frequency distribution was similar in the whole group of patients, in patients with LVH, and in a control group of healthy volunteers. Our data do not support that the I/D ACE genotype determination helps in identifying treated hypertensive patients at higher risk of LVH. Journal of Human Hypertension (2000) 14, 327-331
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Affiliation(s)
- J López-Contreras
- Department of Internal Medicine, Hospital de la Santa Creu i Sant Pau, Universitat Autònoma de Barcelona, Spain
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11
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Gallego F, Fleck O, Li A, Wyrzykowska J, Tinland B. AtRAD1, a plant homologue of human and yeast nucleotide excision repair endonucleases, is involved in dark repair of UV damages and recombination. Plant J 2000; 21:507-518. [PMID: 10758501 DOI: 10.1046/j.1365-313x.2000.00694.x] [Citation(s) in RCA: 69] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Plants are unique in the obligatory nature of their exposure to sunlight and consequently to ultraviolet (UV) irradiation. However, our understanding of plant DNA repair processes lags far behind the current knowledge of repair mechanisms in microbes, yeast and mammals, especially concerning the universally conserved and versatile dark repair pathway called nucleotide excision repair (NER). Here we report the isolation and functional characterization of Arabidopsis thaliana AtRAD1, which encodes the plant homologue of Saccharomyces cerevisiae RAD1, Schizosaccharomyces pombe RAD16 and human XPF, endonucleolytic enzymes involved in DNA repair and recombination processes. Our results indicate that AtRAD1 is involved in the excision of UV-induced damages, and allow us to assign, for the first time in plants, the dark repair of such DNA lesions to NER. The low efficiency of this repair mechanism, coupled to the fact that AtRAD1 is ubiquitously expressed including tissues that are not accessible to UV light, suggests that plant NER has other roles. Possible 'UV-independent' functions of NER are discussed with respect to features that are particular to plants.
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Affiliation(s)
- F Gallego
- Institute of Plant Sciences, ETH Zürich, Universitätstrasse 2, CH-8092 Zürich, Switzerland
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12
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Gallego F, Feuillet C, Messmer M, Penger A, Graner A, Yano M, Sasaki T, Keller B. Comparative mapping of the two wheat leaf rust resistance loci Lr1 and Lr10 in rice and barley. Genome 1998; 41:328-36. [PMID: 9729767 DOI: 10.1139/g98-024] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The wheat genome is large, hexaploid, and contains a high amount of repetitive sequences. In order to isolate agronomically important genes from wheat by map-based cloning, a simpler model of the genome must be used for identifying candidate genes. The objective of this study was to comparatively map the genomic regions of two wheat leaf rust disease resistance loci, Lr1 and Lr10, in the putative model genomes of rice and barley. Two probes cosegregating with the Lr1 gene on chromosome 5DL of wheat were studied. The rice sequences corresponding to the two probes were isolated and mapped. The two probes mapped to two different rice chromosomes, indicating that the organization of the region orthologous to Lr1 is different in rice and wheat. In contrast, synteny was conserved between wheat and barley in this chromosomal region. The Lrk10 gene cosegregated with Lr10 on chromosome 1AS in wheat. The rice gene corresponding to Lrk10 was mapped on rice chromosome 1, where it occurred in many copies. This region on rice chromosome 1 corresponds to the distal part of the group 3S chromosomes in Triticeae. The synteny is conserved between rice chromosome 1 and the Triticeae group 3S chromosomes up to the telomere of the chromosomes. On group 3S chromosomes, we found a gene that is partially homologous to Lrk10. We conclude that in the genomic regions studied, there is limited and only partially useful synteny between wheat and rice. Therefore, barley should also be considered as a model genome for isolating the Lr1 and Lr10 genes from wheat.
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Affiliation(s)
- F Gallego
- Department of Resistance and Quality Breeding, Swiss Federal Research Station for Agroecology and Agriculture, Zürich, Switzerland
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13
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Jiménez-Fuentes MA, Gea J, Pallás O, Gallego F, Félez MA, Broquetas JM. [Fiber morphometry of the external intercostal muscle. Comparison of dominant and nondominant sides in patients with severe COPD]. Arch Bronconeumol 1998; 34:189-93. [PMID: 9611653 DOI: 10.1016/s0300-2896(15)30451-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The general morphometric characteristics of the external intercostal muscle (EIM) of patients with chronic respiratory disease have been well described. Because this muscle is highly accessible, it can provide an ideal model for longitudinal studies using consecutive biopsies of both sides. Whether or not the EIM fiber phenotype is homogeneous on dominant (D) and non dominant (ND) sides is unknown, however. To evaluate possible structural differences in right and left EIM in patients with COPD, eight patients (63 +/- 7 years of age) were enrolled. Lung function, respiratory muscle power, general muscle power and nutritional state were evaluated. Biopsies of the fifth EIM were taken from both sides. Specimens were processed in parallel manner to determine conventional morphometry (hematoxylin-eosin staining), including minimum diameter (Dm) and fiber area (Ar) in cross sections. Fibers were typed by ATPase (at pH 4.2, 4.6 and 9.4) and NADH-TR staining. Nutrition was normal in all patients. All patients had severe COPD (FEV1 27 +/- 7% of reference, limits 13 to 38% of reference) with air entrapment (RV 163 +/- 36% of reference, limits 181 to 276% of reference). None of the patients showed respiratory insufficiency at rest (PaO2 72 +/- 7 mmHg). Peripheral musculoskeletal power measured by manual dynamometer showed no significant right-left differences: D 29 +/- 2 and ND 28 +/- 3 dynes. Morphometric study of 16 muscle specimens showed no significant differences between fiber size on D and ND sides. DmD was 47 +/- 10 microns and ArD, was 2,595 +/- 1,249 microns2. DmD was 49 +/- 9 microns and ArD was 2,636 +/- 953 microns2. Likewise, no significant differences were found between D and ND fiber types: type ID 51 +/- 4% and type IID 49 +/- 5% versus type IND 52 +/- 4% and type IIND 48 +/- 4%. EIM on N and ND sides is homogeneous at the fifth intercostal space. This finding, along with the scarcely invasive nature of the technique for collecting specimens leads us to suggest that longitudinal studies might be performed on the structural effects of various pharmacological or physical treatments followed by COPD patients
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Affiliation(s)
- M A Jiménez-Fuentes
- Servicio de Neumología, Hospital del Mar-IMIM, Universidad Autónoma de Barcelona
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14
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Abstract
The diaphragm is the main inspiratory muscle. It is composed of two parts, the costal and crural, with both anatomical and functional differences. The general morphometric characteristics of the diaphragm have been described in various species but homogeneity throughout the muscle has not been adequately studied. The aim of this study was to evaluate the fiber phenotype of various parts of the diaphragm. The entire diaphragm muscles of five New Zealand rabbits were removed and each was divided into quarters. The specimens were processed for morphometry (hematoxyllineosin stains, NADH-TR and ATPase at pH levels of 4.2, 4.6 and 9.4). For each portion we measured percent and size of fibers, expressing the latter as minimum diameter (Dm), measured area (Ar) and calculated area (Ac). Left and right diaphragm hemispheres (20 portions examined) were similar for fiber percentages and sizes. For left and right halves, respectively 50 +/- 2 and 51 +/- 4% of fibers were type I; type I Dm measurements were 38 +/- 5 and 41 +/- 4 microns; type I Ar values were 1798 +/- 481 and 2030 +/- 390 micron 2; type I Ac values were 1181 +/- 360 and 1321 +/- 382 micron 2; type II Dm values were 46 +/- 4 and 46 +/- 5 microns; type II Ar values were 2466 +/- 388 micron 2 and 2539 +/- 456 micron 2; type II Ac data were 1642 +/- 255 and 1655 +/- 382 micron 2. We likewise found no differences between costal and crural portions of the muscle (n = 20). For costal and crural portions, respectively, 50 +/- 3 and 50 +/- 2% of fibers were type I; type I Dm sizes were 39 +/- 5 and 40 +/- 4 microns; type I Ar measurements were 1859 +/- 521 and 1964 +/- 365 micron 2; type I Ac figures were 1231 +/- 317 and 1266 +/- 288 micron 2; type II Dm were 47 +/- 4 and 44 +/- 3 microns; type II Ar were 2563 +/- 481 and 2430 +/- 331 micron 2; type II Ac were 1729 +/- 373 and 1557 +/- 212 micron 2. Type II fibers, however, were somewhat larger than type I fibers in all portions (p = 0.001). New Zealand rabbit diaphragm muscle has similar percentages of slow and rapid contraction fibers. The size is not different from that observed in other species of mammals of similar size. Fiber type proportions are similar throughout the muscle, with more type II fibers present in all areas. The morphometric characters, therefore, suggest an homogeneous throughout the diaphragm, suggesting homogeneous response of the muscle to usual loads, and also suggesting the possibility of proposing longitudinal morphometric studies using this species as a model.
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15
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Ibarra LSD, Gallego F. Factors related to lipohypertrophy in insulin-treated diabetic patients: role of educational intervention. ACTA ACUST UNITED AC 1998. [DOI: 10.1002/pdi.1960150108] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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16
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Valenzuela M, Martín-Ruiz JL, Alvarez-Cienfuegos E, Caballero AM, Gallego F, Carmona I, Rodríguez-Téllez M. Colitis cystica profunda: imaging diagnosis and conservative treatment: report of two cases. Dis Colon Rectum 1996; 39:587-90. [PMID: 8620815 DOI: 10.1007/bf02058718] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
UNLABELLED Rectally localized colitis cystica profunda can simulate mucosecretory carcinoma. PURPOSE AND METHODS Because endoscopic examination and barium enema do not clarify the diagnosis, other diagnostic imaging methods such as transrectal ultrasonography, computerized tomography, or magnetic resonance imaging are needed. RESULTS Transrectal ultrasonography identifies multiple cysts in the rectal submucosa, with areas of echorefringent fibrosis between cysts, and confirms the absence of lymph node involvement or invasion of the muscular layer. Findings with computerized tomography and magnetic resonance imaging have not previously been described for colitis cystica profunda. With computerized tomography, the lesion appears as a noninfiltrating entity in the submucosa, with loss of perirectal layers of fatty tissue and thickening of the levator ani muscle. With nuclear magnetic imaging, nodulations produce intense signals that increase in T2, illustrating the mucoprotein content of the cysts. The presence in surgical biopsy material of large, whole cysts confirms the diagnosis. CONCLUSION Reeducation of bowel habits aimed at avoiding straining and a high-fiber diet together with bulk laxatives can lead to complete remission of lesions in 6 to 18 months.
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Affiliation(s)
- M Valenzuela
- Department of Medicine, School of Medicine, University of Granada, Spain
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17
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Gallego F, Fernandez-Busquets X, Daban JR. Mechanism of nucleosome dissociation produced by transcription elongation in a short chromatin template. Biochemistry 1995; 34:6711-9. [PMID: 7756302 DOI: 10.1021/bi00020a016] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
We have used a linear DNA template (239 bp) containing a nucleosome positioning sequence (NX1) downstream of the T7 RNA polymerase promoter to study the mechanism of transcription elongation through a nucleosome. Under ionic strength approaching physiological conditions we have observed that transcription causes nucleosome dissociation and histone redistribution within the template. We have examined the role of the different elements that, in principle, could induce nucleosome dissociation during transcription. The high affinity of histones for single-stranded DNA observed in titration experiments performed using the purified (+) and (-) strands of the NX1 fragment suggests that nucleosome dissociation is not due to the formation of segments of single-stranded DNA by RNA polymerase in the elongation process. Furthermore, our results show that although RNA can interact with core histones, the synthesized RNA is not bound to the histones dissociated by transcription. Our results indicate that core histones released during transcription can be bound to naked DNA and chromatin (with or without histones H1-H5). From the dynamic properties of excess histones bound to chromatin, we suggest a nucleosome transcription mechanism in which displaced histones are transiently bound to chromatin and finally are reassembled with DNA after the passage of the polymerase.
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Affiliation(s)
- F Gallego
- Departament de Bioquímica i Biologia Molecular, Facultad de Ciències, Universitat Autónoma de Barcelona, Bellaterra, Spain
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Affiliation(s)
- A Muñoz
- Departamento de Radiodiagnóstico, Hospital Universitario de San Carlos, Ciudad Universitaria, Madrid, Spain
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20
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Kutter D, Braun C, Gallego F, Stirn-Thoma S. Screening urine before microscopy, by automated test-strip preselection: clinical evaluation of the improved Rapimat II/T (Behring). Clin Chem 1988; 34:1600-2. [PMID: 3402063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
In many laboratories, microscopy of urines is restricted to specimens selected on the basis of positive tests, mainly for protein, blood, nitrite, and leukocyte esterase. Here, we analyzed several hundred specimens by use of multiple dipsticks, read in an improved reflectometer. By comparing the results with quantitative microscopy, it could be shown that this system allows selection, with acceptable sensitivity and specificity, of those specimens that are likely to contain clinically important microscopic elements.
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Affiliation(s)
- D Kutter
- Centre Universitaire de Luxembourg
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21
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Kutter D, Braun C, Gallego F, Stirn-Thoma S. Screening urine before microscopy, by automated test-strip preselection: clinical evaluation of the improved Rapimat II/T (Behring). Clin Chem 1988. [DOI: 10.1093/clinchem/34.8.1600] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Abstract
In many laboratories, microscopy of urines is restricted to specimens selected on the basis of positive tests, mainly for protein, blood, nitrite, and leukocyte esterase. Here, we analyzed several hundred specimens by use of multiple dipsticks, read in an improved reflectometer. By comparing the results with quantitative microscopy, it could be shown that this system allows selection, with acceptable sensitivity and specificity, of those specimens that are likely to contain clinically important microscopic elements.
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Affiliation(s)
- D Kutter
- Centre Universitaire de Luxembourg
| | - C Braun
- Centre Universitaire de Luxembourg
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23
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Santamaría A, Gallego F, Muñoz ME. Rheological and processing characteristics of polystyrene in the vicinity of Tll transition. POLYM ENG SCI 1985. [DOI: 10.1002/pen.760250308] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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González C, Gallego F, Swiatopolk-Mirski A, Vallejo E. [On the essential oils found in the aerial part of Tanacetum microphyllum D.C., in relation to the azulenes present in its leaves in the summer season]. Farmacognosia 1966; 26:51-83. [PMID: 5987944] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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Gallego F, Swiatopolk-Mirski A, Vallejo E. [Contribution to the study of Chenopodium botrys L. in relation to its essential oil]. Farmacognosia 1965; 25:69-87. [PMID: 5895978] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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