Search Results - (Author, Cooperation:M. Cardona)

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  1. 1
    Staff View
    Publication Date:
    2018-03-06
    Publisher:
    MDPI Publishing
    Electronic ISSN:
    1424-8220
    Topics:
    Chemistry and Pharmacology
    Electrical Engineering, Measurement and Control Technology
    Published by:
    http://www.mdpi.com/

    Latest Papers from Table of Contents or Articles in Press
  2. 2
    Staff View
    Publication Date:
    2018-07-03
    Publisher:
    The American Association for Cancer Research (AACR)
    Print ISSN:
    0008-5472
    Electronic ISSN:
    1538-7445
    Topics:
    Medicine
    Published by:
    http://www.aacr.org/

    Latest Papers from Table of Contents or Articles in Press
  3. 3
    Staff View
    Publication Date:
    2011-10-08
    Publisher:
    Nature Publishing Group (NPG)
    Print ISSN:
    0028-0836
    Electronic ISSN:
    1476-4687
    Topics:
    Biology
    Chemistry and Pharmacology
    Medicine
    Natural Sciences in General
    Physics
    Keywords:
    Animals ; Apoptosis ; Body Weight/genetics ; Cardiomegaly/*enzymology/genetics/*pathology/physiopathology ; Cell Respiration ; Chromosomes, Mammalian/genetics ; Crosses, Genetic ; Endodeoxyribonucleases/deficiency/genetics/*metabolism ; Female ; Gene Expression Regulation ; Genes, Mitochondrial/genetics ; Hypertrophy, Left Ventricular/enzymology/genetics/pathology/physiopathology ; Lipid Metabolism ; Male ; Mitochondria/genetics/*metabolism/pathology ; Organ Size/genetics ; Quantitative Trait Loci/genetics ; RNA-Binding Proteins/metabolism ; Rats ; Rats, Inbred Strains ; Reactive Oxygen Species/metabolism ; Receptors, Estrogen/metabolism ; Transcription Factors/metabolism
    Published by:
    http://www.nature.com/

    Latest Papers from Table of Contents or Articles in Press
  4. 4
    Staff View
    ISSN:
    1432-5195
    Source:
    Springer Online Journal Archives 1860-2000
    Topics:
    Medicine
    Description / Table of Contents:
    Résumé. Nous avons effectué une étude du clou centro-médullaire verrouillé de Grosse-Kempf pour déterminer les forces qui affectent le plus sa structure et la place où elles se produisent. L’étude, de type statique-linéaire, a été faite avec un programme d’éléments finis en appliquant des forces de compression, de flexion et de torsion. Les résultats indiquent une bonne résistance du clou aux forces de compression et de flexion, mais non aux forces de torsion. Celles-ci créent un maximum de contrainte à la partie postérieure du clou au niveau de la modification de la section entre zone fendue et zone non fendue.
    Notes:
    Summary. We have carried out a biomechanical study of the forces acting on the Grosse-Kempf intramedullary nail to determine those which most affect its structure. We have used finite element analysis to assess the distribution of compression, flexion and torsion forces. The qualitative and quantitative distribution of the tension on the surface of the nail has been observed. We have shown that the torsional force is most important and it is exerted in the posterior part of the nail where there is a change from the unslotted to the slotted section.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1007/s002640050132

    Articles: DFG German National Licenses
  5. 5
    Staff View
    Publication Date:
    2018-05-26
    Publisher:
    The American Society for Microbiology (ASM)
    Print ISSN:
    0066-4804
    Electronic ISSN:
    1098-6596
    Topics:
    Biology
    Medicine
    Published by:
    http://www.asm.org/

    Latest Papers from Table of Contents or Articles in Press
  6. 6
    A. C. Aguilar, J. C. Cardona, M. N. Ferreira, and J. Papavassiliou
    American Physical Society (APS)
    Published 2018
    Staff View
    Publication Date:
    2018-07-03
    Publisher:
    American Physical Society (APS)
    Print ISSN:
    0556-2821
    Electronic ISSN:
    1089-4918
    Topics:
    Physics
    Keywords:
    Strong Interactions
    Published by:
    http://www.aps.org/

    Latest Papers from Table of Contents or Articles in Press
  7. 7
    Logothetidis, S. ; Cardona, M. ; Trallero-Giner, C.

    [S.l.] : American Institute of Physics (AIP)
    Published 1990
    Staff View
    ISSN:
    1089-7550
    Source:
    AIP Digital Archive
    Topics:
    Physics
    Notes:
    The E0 exciton splitting into Ev10 and Ev20 excitons (due to lattice mismatch), their energy shift and the lifetime broadening are obtained in the GaAs/AlxGa1−xAs alloy system grown by liquid-phase epitaxy from the analysis of spectroscopic ellipsometry measurements in the temperature range between 12 and 800 K. The lifetime broadenings of these excitons at low temperature is shown to be described well by the statistical fluctuations of the alloy composition caused by the random distribution of Al and Ga on the cation sites (Schubert's model). The Ev10 exciton lifetime broadening was found to be larger in the Ga-rich region as compared to the corresponding one of the Ev20 exciton and smaller in the Al-rich region. The former broadening is explained qualitatively by the different effective masses (mv1Γ〉mv2Γ), whereas the latter is produced in terms of the increase in the density of states of the holes in the V2 valence band by the increasing energy splitting δEs with x.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1063/1.344974

    Articles: DFG German National Licenses
  8. 8
    Scamarcio, G. ; Brandt, O. ; Tapfer, L. ; Mowbray, D. J. ; Cardona, M. ; Ploog, K.

    [S.l.] : American Institute of Physics (AIP)
    Published 1991
    Staff View
    ISSN:
    1089-7550
    Source:
    AIP Digital Archive
    Topics:
    Physics
    Notes:
    The structural and vibrational properties of superlattices composed of many periods of highly mismatched InAs and GaAs layers have been studied by means of x-ray diffraction and Raman scattering as a function of the sample geometry. X-ray diffraction measures the average lattice mismatch between the superlattice and the substrate. The long-range order influences the propagative acoustic phonons whereas strain and confinement effects compete in determining the optic vibration frequencies of the InAs layers. The linewidth of the main superlattice peak in the diffraction patterns and the scattering intensities of the acoustic phonons are related to the actual shape of the interfaces. We find that the stability of the structures depends on the total number of periods, in agreement with the predictions of equilibrium elasticity theory. However, the competition between the different relaxation processes is governed by the individual layer thicknesses.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1063/1.347365

    Articles: DFG German National Licenses
  9. 9
    Kircher, J. ; Böhringer, W. ; Dietrich, W. ; Hirt, H. ; Etchegoin, P. ; Cardona, M.

    [S.l.] : American Institute of Physics (AIP)
    Published 1992
    Staff View
    ISSN:
    1089-7623
    Source:
    AIP Digital Archive
    Topics:
    Physics
    Electrical Engineering, Measurement and Control Technology
    Notes:
    The design and construction of an apparatus for the application of compressive uniaxial stress is described. In contrast to older machines a hydraulic force transmission is used allowing for a very compact and lightweight sample holder/stress unit. The less bulky machine allows more accurate alignment of the stressed sample in an optical experiment. The large force the machine can exert facilitates the use of samples with a large cross section such as those desirable for ellipsometric measurements. A low budget version of the machine, based on motorbike components, is suggested. The machine is used in conjuction with a rotating analyzer ellipsometer to measure the dielectric function under uniaxial stress. From these data we are able to extract the components of the piezo-optical tensor. We demonstrate this for the case of germanium.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1063/1.1143606

    Articles: DFG German National Licenses
  10. 10
    Lew Yan Voon, L. C. ; Willatzen, M. ; Cardona, M. ; Ram-Mohan, L. R.

    [S.l.] : American Institute of Physics (AIP)
    Published 1996
    Staff View
    ISSN:
    1089-7550
    Source:
    AIP Digital Archive
    Topics:
    Physics
    Notes:
    A multiband k⋅p theory was recently proposed [L. H. Peng and C. G. Fonstad, J. Appl. Phys. 77, 747 (1995)] in order to discuss the influence of band mixing on the selection rules for intersubband and interband optical transitions in quantum wells. We point out here that the analysis presented is incorrect. © 1996 American Institute of Physics.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1063/1.362829

    Articles: DFG German National Licenses
  11. 11
    Zhang, P. ; Haage, T. ; Habermeier, H.-U. ; Ruf, T. ; Cardona, M.

    [S.l.] : American Institute of Physics (AIP)
    Published 1996
    Staff View
    ISSN:
    1089-7550
    Source:
    AIP Digital Archive
    Topics:
    Physics
    Notes:
    Thin films of YBa2Cu3O7−δ (YBCO) on LaSrAlO4 (001) substrates with various thicknesses have been investigated by Raman spectroscopy. The Raman spectra of the films have been obtained by properly subtracting the spectrum of the substrate from the recorded spectra. This data anaysis enables us to determine the Raman spectra of YBCO films with thicknesses down to 12 nm (about 10 unit cells). The evolution of the peak positions and the linewidths of the B1g mode with thickness allow us to conclude that the residual strains in these films are negligibly small within the measured thickness range. The influence of the birefringence on measurement of the degree of epitaxy by Raman has been studied. With the reduction of film thickness the degree of epitaxy is slightly increased in these films. © 1996 American Institute of Physics.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1063/1.363149

    Articles: DFG German National Licenses
  12. 12
    Kamarás, K. ; Barth, K.-L. ; Keilmann, F. ; Henn, R. ; Reedyk, M. ; Thomsen, C. ; Cardona, M. ; Kircher, J. ; Richards, P. L. ; Stehlé, J.-L.

    [S.l.] : American Institute of Physics (AIP)
    Published 1995
    Staff View
    ISSN:
    1089-7550
    Source:
    AIP Digital Archive
    Topics:
    Physics
    Notes:
    By combining reflectance spectroscopy and spectroscopic ellipsometry, the complex dielectric function of SrTiO3 in the frequency range 40–5000 cm−1 at 20, 100, 200, and 300 K has been determined. Using a factorized description, analytical expressions for the optical quantities were derived, giving excellent agreement with the experimental data. These can be used for two-layer fits of films on SrTiO3, e.g., of high-Tc superconductors. The fit parameters complement very well those found at higher temperatures. © 1995 American Institute of Physics.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1063/1.360364

    Articles: DFG German National Licenses
  13. 13
    Kuball, M. ; Cardona, M. ; Mazuelas, A. ; Ploog, K. H. ; Pérez-Camacho, J. J. ; Silveira, J. P. ; Briones, F.

    [S.l.] : American Institute of Physics (AIP)
    Published 1995
    Staff View
    ISSN:
    1089-7550
    Source:
    AIP Digital Archive
    Topics:
    Physics
    Notes:
    Using x-ray diffraction and ellipsometry we have studied the incorporation process of SnTe in GaAs for n-type doping. Combining these two techniques allows us to decide whether SnTe is incorporated pairwise, as has been proposed in the literature. We found SnTe doping to change the E1 and E1+Δ1 critical point parameters in a way similar to that previously reported for n-type Si-doped GaAs. X-ray diffraction and Hall measurements show that the free carrier concentration is more than 1/2 of the [Sn]+[Te] concentration. We thus conclude that a large proportion of SnTe is incorporated as independent Sn and Te dopant atoms. © 1995 American Institute of Physics.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1063/1.359458

    Articles: DFG German National Licenses
  14. 14
    Spitzer, J. ; Höpner, A. ; Kuball, M. ; Cardona, M. ; Jenichen, B. ; Neuroth, H. ; Brar, B. ; Kroemer, H.

    [S.l.] : American Institute of Physics (AIP)
    Published 1995
    Staff View
    ISSN:
    1089-7550
    Source:
    AIP Digital Archive
    Topics:
    Physics
    Notes:
    A series of five short-period (InAs)6/(AlSb)6 superlattices, grown either with AlAs-like, InSb-like, or alternating interfaces, were studied by means of x-ray diffraction, high resolution transmission electron microscopy (HRTEM), Raman spectroscopy, photoluminescence and ellipsometry. The combination of these techniques allows us to explain the pronounced differences in the optical and structural properties of both types of interfaces. In samples with an AlAs-like bottom interface x-ray, HRTEM and Raman results demonstrate the differing structural quality to be related to inhomogeneous strain relaxation and As intermixing. The energies of the critical points E0, E1 and E1+Δ1 of the samples with pure AlAs-like interfaces are shifted by more than 100 meV to higher energies with respect to those of the samples with InSb-like interfaces. These differences can be understood on the basis of the different interfacial atomic structure and strain in the samples. © 1995 American Institute of Physics.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1063/1.359004

    Articles: DFG German National Licenses
  15. 15
    Popovic, Z. V. ; Cardona, M. ; Tapfer, L. ; Ploog, K. ; Richter, E. ; Strauch, D.

    Woodbury, NY : American Institute of Physics (AIP)
    Published 1989
    Staff View
    ISSN:
    1077-3118
    Source:
    AIP Digital Archive
    Topics:
    Physics
    Notes:
    The short-period (GaAs)n1(AlAs)n2 superlattices with parameters (n1,n2)=(21,25), (6,42), (14,16), and (23,8) have been grown by molecular beam epitaxy on GaAs substrates along the [012] direction and characterized by x-ray and Raman scattering spectroscopy. The appearance of distinct satellite peaks around the Bragg reflections demonstrates the formation of high quality superlattices. The observed TO and LO confined modes have frequencies which map closely those of the optical phonons of bulk GaAs and AlAs in the Γ-W-X direction.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1063/1.101415

    Articles: DFG German National Licenses
  16. 16
    Humlícek, J. ; Garriga, M. ; Alonso, M. I. ; Cardona, M.

    [S.l.] : American Institute of Physics (AIP)
    Published 1989
    Staff View
    ISSN:
    1089-7550
    Source:
    AIP Digital Archive
    Topics:
    Physics
    Notes:
    We report pseudodielectric functions of SixGe1−x alloys at room temperature, measured ellipsometrically on polycrystalline samples and single-crystal epitaxial layers, in the 1.7–5.6 eV range. Accurate values of the E1 threshold energies are obtained from numerically differentiated spectra. The measured dependence of E1 on x provides an efficient way to determine the alloy composition x. The spectral and compositional dependence of the optical constants forms a data base for optical studies of Si/SiGe layered structures.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1063/1.342720

    Articles: DFG German National Licenses
  17. 17
    Johnson, R. L. ; Barth, J. ; Cardona, M. ; Fuchs, D. ; Bradshaw, A. M.

    [S.l.] : American Institute of Physics (AIP)
    Published 1989
    Staff View
    ISSN:
    1089-7623
    Source:
    AIP Digital Archive
    Topics:
    Physics
    Electrical Engineering, Measurement and Control Technology
    Notes:
    The design, construction, and performance of an automatic photometric ellipsometer with rotating analyzer for the VUV region (5–30 eV) is described. The use of a synchrotron radiation source and triple-reflection polarizers makes this new spectral region accessible to spectroscopic ellipsometry. New dielectric function data are presented for InP(110), YBa2Cu3O7, and epitaxial CaF2/Si(111).
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1063/1.1140823

    Articles: DFG German National Licenses
  18. 18
    Spitzer, J. ; Fuchs, H. D. ; Etchegoin, P. ; Ilg, M. ; Cardona, M. ; Brar, B. ; Kroemer, H.

    Woodbury, NY : American Institute of Physics (AIP)
    Published 1993
    Staff View
    ISSN:
    1077-3118
    Source:
    AIP Digital Archive
    Topics:
    Physics
    Notes:
    Two short-period InAs/AlSb superlattices, grown with an AlAs-like interface and an InSb-like interface, respectively, were studied with Raman spectroscopy, x-ray diffraction, and ellipsometry. Our measurements show that the InSb-like interface grows perfectly pseudomorphically, whereas the sample with the AlAs-like interface shows indications of relaxation and As interdiffusion. This different interface quality seems to be a fundamental problem, rather than the result of the growth technique.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1063/1.109393

    Articles: DFG German National Licenses
  19. 19
    Shields, A. J. ; Nötzel, R. ; Cardona, M. ; Däweritz, L. ; Ploog, K.

    Woodbury, NY : American Institute of Physics (AIP)
    Published 1992
    Staff View
    ISSN:
    1077-3118
    Source:
    AIP Digital Archive
    Topics:
    Physics
    Notes:
    Using resonant Raman spectroscopy we have studied novel GaAs/AlAs superlattice (SL) structures, grown on (113) substrates, where the GaAs and AlAs layer widths vary periodically on a nanometer scale along the lateral [11¯0] direction. We observe sharp confined LO phonon lines for both (113) and simultaneously grown (001) SLs, for a range of different layer widths, whose frequencies map the bulk GaAs LO dispersion. The confined phonon lines of the (113) SLs show a side peak, which can be assigned to a mode with finite k vector parallel to the layers, induced by the lateral periodicity.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1063/1.106905

    Articles: DFG German National Licenses
  20. 20
    Zhang, J. M. ; Cardona, M.

    Woodbury, NY : American Institute of Physics (AIP)
    Published 1997
    Staff View
    ISSN:
    1077-3118
    Source:
    AIP Digital Archive
    Topics:
    Physics
    Notes:
    The surfactant effect of atomic hydrogen on the incorporation of silicon into (100)-, (111)A-, and (311)A-oriented GaAs grown by hydrogen-assisted molecular beam epitaxy has been studied with Raman spectroscopy. Local vibrational modes (LVMs) of SiGa and SiAs impurities are observed for excitation nearly resonant with the E1 energy gap. Site switch of the doping Si atoms from Ga to As lattice sites due to the surfactant effect of H during growth of the high-index doped layers was directly monitored by changes of the normalized intensity of the LVMs. An increase of the free carrier concentration in p-type samples and a decrease in n-type samples resulting from this site switch were also observed in the plasmon-phonon coupled modes as observed in Raman scattering. Similar changes in carrier concentrations were observed by means of electrical transport measurements. © 1997 American Institute of Physics.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1063/1.119407

    Articles: DFG German National Licenses