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  • 1
    Electronic Resource
    Electronic Resource
    Comparative study of atomic ordering and alloy clustering in InGaP crystals grown by metalorganic vapor phase epitaxy, chloride-vapor phase epitaxy, and liquid phase epitaxy (1990)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 68 (1990), S. 4268-4271 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: We describe the results of the transmission electron microscope study of ordered and modulated structures in InGaP alloy semiconductors grown on (001) GaAs substrates by metalorganic vapor phase epitaxy, chloride-vapor phase epitaxy, and liquid phase epitaxy. Strong ordering of CuPt-type has been observed in InGaP grown by metalorganic vapor phase epitaxy at 630 °C, which is associated with an abnormality in the photoluminescence peak energy. CuPt-type ordered structures have also been observed in crystals grown by chloride-vapor phase epitaxy, but the degree of ordering is weaker and crystals grown at 576–740 °C exhibit normal photoluminescence peak energies. On the other hand, in crystals grown by liquid phase epitaxy, no ordered structure is found and the crystals exhibit normal photoluminescence peak energies. There is no dependence of modulated structures on the growth method since they are observed in all crystals. These results also lead us the previous conclusion by Kondow and co-workers that the ordered structures are not generated under thermal equilibrium conditions but rather by the diffusion and reconstruction of deposited atoms on the growth surface.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.346218
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  • 2
    Electronic Resource
    Electronic Resource
    Ultraviolet photoemission study of oligothiophenes: The effect of irregularity on π-electron systems (1988)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 89 (1988), S. 1198-1199 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.455232
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  • 3
    Electronic Resource
    Electronic Resource
    Ultraviolet photoemission study of oligothiophenes: π-band evolution and geometries (1990)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 92 (1990), S. 4077-4092 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: Ultraviolet photoelectron spectroscopy (UPS) has been applied to the investigation of the electronic structure of oligothiophenes with 4–8 thiophene rings. In a series of α-linked oligomers (αn with n being the number of rings), a systematic evolution of the π band is observed. Several peaks which correspond to the π band are observed in the region of 0.7–3 eV below the Fermi level (EF), and the bandwidth becomes broader with increasing n. The nonbonding π band is observed at 3.5 eV below EF and its energy is almost independent of the number of thiophene units. UPS spectra of α7 and α8 are fairly similar to the spectra of polythiophene, showing that these oligomers are good model compounds of the polymer. The ionization threshold energy of α7 and polythiophene was observed to be 5.3 eV. The effect of irregularity on the π-electron system was also studied by using oligomers which contain a β linkage or a vinylene group at the middle of the molecule. The UPS spectra showed that the β linkages significantly affect the electronic structure of polythiophene, while the vinylene group does not. In order to analyze the UPS spectra and to investigate the electronic structures of oligomers, the orbital energies and the geometries of these oligomers are calculated by the semiempirical MNDO-SCF-MO (modified neglect of diatomic overlap self-consistent-field molecular orbital) method. Theoretically simulated spectra of these oligothiophenes derived from the obtained orbital energies by Gaussian broadening are compared with the observed ones. The agreement between the observed and calculated spectra is very good, particularly in the π region. It is shown from the optimized geometry that (1) αn 's have planar structure and π electrons are delocalized, (2) the oligomer with β linkages has nonplanar structure leading to limited delocalization of π electrons, and (3) the oligomers with a vinylene group are almost planar and the disturbance by the vinylene group on the delocalization is small.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.458561
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  • 4
    Electronic Resource
    Electronic Resource
    Time evolution from linear to nonlinear stages in magnetohydrodynamic parametric instabilities (1989)
    New York, NY : American Institute of Physics (AIP)
    Physics of Fluids 1 (1989), S. 1405-1415 
    Details
    ISSN: 1089-7666
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The nonlinear evolution of the magnetohydrodynamic (MHD) parametric instability of wave fluctuations propagating along an unperturbed magnetic field is investigated. Both a magnetohydrodynamic perturbation-theoretical approach and a nonlinear MHD simulation are used. It is shown that high harmonic waves are rapidly excited by wave–wave coupling, and that the wave spectrum evolves from a state containing a small number of degrees of freedom in k space to one which contains a large number of degrees of freedom. It is found that the spectral evolution prior to nonlinear saturation is well described by the perturbation theory. During this stage, the ratio of the growth rate of the nth harmonic wave to the linear growth rate of the fundamental wave is n. The nonlinear saturation stage is characterized by a frequency shift of the fundamental wave that destroys the wave–wave resonance condition which, in turn, causes the wave amplitude to cease its growth.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.858971
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  • 5
    Electronic Resource
    Electronic Resource
    Evolution of nonlinear polarization in localized and finite amplitude Alfvén waves (1988)
    [S.l.] : American Institute of Physics (AIP)
    Physics of Fluids 31 (1988), S. 3271-3279 
    Details
    ISSN: 1089-7666
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Theoretical and computational study for a polarization change of localized and finite amplitude Alfvén waves propagating parallel to an applied magnetic field is presented using both reductive perturbation theory and numerical simulations. In the magnetohydrodynamic limit (ω(very-much-less-than)Ωi) where right- and left-hand circularly polarized waves are degenerate, one of the transverse components of the circularly polarized Alfvén wave is stable as it propagates, but the other component is unstable to either self-focusing or diffraction effects. Consequently, the wave changes its polarization from circular to linear. In the high frequency regime (ω(approximately-greater-than)Ωi), where two circularly polarized waves (right- and left-hand circularly polarized waves) are not degenerate, two transverse components of the circularly polarized Alfvén wave are strongly coupled to each other, and there is almost no polarization change.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.866939
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  • 6
    Electronic Resource
    Electronic Resource
    Wavelength-dependent photochemical behavior in 9,10-dimethylenebianthracene (1976)
    s.l. : American Chemical Society
    The @journal of physical chemistry 〈Washington, DC〉 80 (1976), S. 30-32 
    Details
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1021/j100542a006
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  • 7
    Electronic Resource
    Electronic Resource
    Effect of inhaled corticosteroid on an immunoreactive thymus and activation-regulated chemokine expression in the bronchial biopsies from asthmatics (2005)
    Oxford, UK : Munksgaard International Publishers
    Allergy 60 (2005), S. 0 
    Details
    ISSN: 1398-9995
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Background:  Bronchial asthma is characterized by airway inflammation, notably because of eosinophils and T cells. Thymus and activation-regulated chemokine (TARC) is known to selectively attract Th2 cells, and is increased in response to interleukin (IL)-4 and IL-13, which share a common receptor, IL-4 receptor alpha (IL-4Rα). While corticosteroids have proven, very effective in modifying airway inflammation, the effect of corticosteroids on TARC in asthmatics has been little studied.Objective:  We examined the effects of inhaled budesonide (BUD) on the expression of TARC and the number of inflammatory cells in bronchial biopsy specimens taken from asthma patients.Methods:  Inhaled BUD 800 μg daily, or placebo was administered for 3 months in a double-blind, parallel-group study, and bronchial biopsies were performed before and after treatment. Biopsy specimens were examined by immunocytochemistry.Results:  We observed a significant decrease in the epithelial expression of TARC (P 〈 0.01) in the BUD group compared with the placebo group. This was accompanied by decreases in the number of eosinophils (P 〈 0.01), CD3+ T cells (P 〈 0.05), and CD4+ T cells (P 〈 0.01). A significant correlation was found between changes in epithelial TARC and in IL-4Rα immunoreactivity (rs = 0.66, P 〈 0.01).Conclusions:  These findings suggest that corticosteroid asthma treatment can reduce infiltration of the airway by inflammatory cells, an effect modulated by down-regulation of bronchial epithelial TARC expression.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1398-9995.2005.00694.x
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  • 8
    Electronic Resource
    Electronic Resource
    Effect of suplatast tosilate on goblet cell metaplasia in patients with asthma (2005)
    Oxford, UK : Munksgaard International Publishers
    Allergy 60 (2005), S. 0 
    Details
    ISSN: 1398-9995
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Background:  Goblet cell metaplasia is a pathologic characteristic of asthma, associated with excess mucus secretion. Interleukin (IL)-4 and IL-13 plays an important role in mucus hypersecretion. Suplatast tosilate (suplatast), an antiallergic agent, is a Th2 cytokine inhibitor that suppresses the synthesis of IL-4, IL-5, IL-13, and eosinophilic airway inflammation.Objective:  We examined the effects of suplatast on mucus production in bronchial biopsy specimens taken from asthmatic subjects.Methods:  Oral suplatast 300 mg daily, or placebo was administered for 3 months in a double-blind, parallel-group study in 25 patients with asthma. Biopsy specimens were evaluated at before and after treatment for alcian blue/period acid-Schiff (AB/PAS), MUC5AC staining in bronchial epithelium and IL-4+, IL-13+ cells as well as inflammatory cells in lamina propria.Results:  There were significant decreases in the percentage of AB/PAS (P 〈 0.01) and MUC5AC (P 〈 0.01) stained area in the suplatast group. These changes were accompanied by significant decreases in IL-4+ and IL-13+ cells in suplatast-treated subjects. Additionally, we have observed that the number of infiltrating eosinophils and CD4+ T cells significantly decreased.Conclusions:  These findings suggest that suplatast prevents goblet cell metaplasia through modulation of Th2 cytokine production and the recruitment of eosinophils and CD4+ T cells in the asthmatic airways.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1398-9995.2005.00897.x
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  • 9
    Electronic Resource
    Electronic Resource
    Electron spin resonance and optical detection of manganese(IV) tetraphenylporphyrin (1982)
    s.l. : American Chemical Society
    The @journal of physical chemistry 〈Washington, DC〉 86 (1982), S. 4537-4539 
    Details
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1021/j100220a017
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  • 10
    Electronic Resource
    Electronic Resource
    Formation of the charge-transfer and constrained complexes of cobalt(II) tetraphenylporphyrin in rigid solution (1980)
    s.l. : American Chemical Society
    The @journal of physical chemistry 〈Washington, DC〉 84 (1980), S. 3437-3440 
    Details
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1021/j100462a025
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