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  • 1
    Electronic Resource
    Electronic Resource
    Sources of phase noise in homodyne and heterodyne phase modulation devices used for tissue oximetry studies (1998)
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 69 (1998), S. 3042-3054 
    Details
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: The objective of this study was to characterize sources of phase noise in homodyne and heterodyne phase modulation devices (PMDs) used for tissue oximetry measurements. Each PMD incorporates a laser diode modulated at a radio frequency in the 50–200 MHz range, an optical detector and a homodyne/heterodyne phase sensitive detector. The intensity modulated light which propagates through tissue is attenuated and undergoes a phase shift, which reflects the mean time of flight of the photons through the tissue. The measured amplitude and phase can be used to determine hemoglobin saturation in tissues using equations based on diffusion theory. Four studies were performed to characterize the sources of phase noise. First, the signal to noise ratio was characterized to determine if the PMDs are operating at the shot noise or detector noise limit. Second, the accuracy of the three PMDs for measuring phase shifts in tissue were compared by using them to measure the phase shift as a function of path length change in air, at a constant amplitude, and at signal to noise ratios comparable to that measured from tissue. The third source of noise measured was the phase shift that results from optical attenuation of the signal (phase-amplitude cross talk) at a constant path length, to characterize intensity dependent phase shifts in the PMDs. Finally, the interchannel interference of a dual wavelength PMD which uses radio frequency multiplexing to perform phase measurements at two wavelengths simultaneously was compared to that of a dual wavelength PMD which uses time multiplexing to perform phase measurements at two wavelengths serially to determine the effect of each on phase error. © 1998 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1149053
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  • 2
    Electronic Resource
    Electronic Resource
    Reducing the induction to abortion interval in termination of second trimester pregnancies: a comparison of mifepristone with laminaria tent (1995)
    Oxford, UK : Blackwell Publishing Ltd
    BJOG 102 (1995), S. 0 
    Details
    ISSN: 1471-0528
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Objective To determine whether mifepristone (RU486) is more effective than laminaria tent in shortening the induction-abortion interval in termination of second trimester pregnancies with gemeprost.Design Prospective randomised comparative trial.Setting Department of Obstetrics and Gynaecology in a University teachng hospital.Subjects Sixty-two women undergoing termination of pregnancy in the second trimester.Interventions The women were allocated at random to one of the two treatment groups. The first group received 600 mg of mifepristone 36 h before administration of gemeprost. In the second group, a medium-sized laminaria tent was inserted 12 h before gemeprost. The pregnancies in both groups were terminated with vaginal gemeprost, 1 mg every 3 h up to a maximum of 5 mg/day.Main outcome measures Induction-abortion intervals, amount of gemeprost required, and incidence of side effects.Results The median induction-abortion interval in the mifepristone group (75 h) was significantly shorter than that in the laminaria tent group (11 h) and significantly fewer gemeprost pessaries were required. There was no significant difference in the amount of narcotic analgesics required or the incidence of side effects between the two groups.Conclusions Mifepristone is more effective than laminaria tent in shortening the induction-abortion interval in termination of second trimester pregnancies.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1471-0528.1995.tb11404.x
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  • 3
    Electronic Resource
    Electronic Resource
    Two-color Z-scan technique with enhanced sensitivity (1995)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 66 (1995), S. 1581-1583 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: A procedure to improve the sensitivity of the two-color Z-scan technique is presented. The sensitivity of the technique as a function of the pump and the probe beam confocal parameters and their relative transverse dimensions is evaluated. The results show that, in the case of small nonlinear phase shift, the sensitivity of the measurements at the probe beam center may be a factor of 4 greater by the appropriate choice of the beams parameters. Results for arbitrary phase shift values and for detection at or out of the probe beam center are also reported. © 1995 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.113858
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  • 4
    Electronic Resource
    Electronic Resource
    UNIFIED CORRELATIONS IN TRANSITION TEMPERATURES OF LOW ALLOY STEELS AND WELD METALS OF VARIOUS TOUGHNESSES (1996)
    Oxford, UK : Blackwell Publishing Ltd
    Fatigue & fracture of engineering materials & structures 19 (1996), S. 0 
    Details
    ISSN: 1460-2695
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Four types of toughness were measured over a range of temperatures using CVN, COD, 4PB and PCI specimens made of low alloy steels and weld metals. It was found that there were unified correlations in transition temperatures among the various toughness parameters which could be realized by the dependence of the yield strengths of the test materials on both temperature and strain rate.The intrinsic reason for the correlations could be attributed to local cleavage conditions, which control the ductile-to-brittle transition during ductile fracture processes, whether the specimens were notched or precracked, under static or dynamic loading conditions. It is suggested that the ductile fracture process itself was independent of test temperature, but the local cleavage condition remains to be more fully understood in future work.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1460-2695.1996.tb00181.x
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  • 5
    Electronic Resource
    Electronic Resource
    Nonclassical Nuclear Localization Signal Provides for High Efficiency, Nonviral Gene Transfer to Nondividing Endothelium (1999)
    [s.l.] : Nature America, Inc.
    Nature biotechnology 17 (1999), S. 39-39 
    Details
    ISSN: 1546-1696
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: [Auszug] Lipofection of nondividing cells is not efficient due to poor endosome escape and poor nuclear import. In vivo, the low division rate of endothelium makes them a difficult target for nonviral gene transfer. Using a cytoplasmic transcription assay by lipofecting pT7bgal with T7 RNA polymerase, we ...
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1038/70175
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  • 6
    Electronic Resource
    Electronic Resource
    Tricarbonyl(η5-2,4-dimethylpentadienyl)iron Tetrafluoroborate (1996)
    Oxford [u.a.] : International Union of Crystallography (IUCr)
    Acta crystallographica 52 (1996), S. 1110-1112 
    Details
    ISSN: 1600-5759
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1107/S010827019501465X
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  • 7
    Electronic Resource
    Electronic Resource
    Benzophenone Adduct of Tris(cyclopentadienyl)dysprosium (1996)
    Oxford [u.a.] : International Union of Crystallography (IUCr)
    Acta crystallographica 52 (1996), S. 1875-1877 
    Details
    ISSN: 1600-5759
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1107/S0108270196002934
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  • 8
    Electronic Resource
    Electronic Resource
    Fractures of posterior wall of acetabulum (1996)
    Springer
    Archives of orthopaedic and trauma surgery 115 (1996), S. 273-275 
    Details
    ISSN: 1434-3916
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Fractures of the posterior wall of the acetabulum form a special group in acetabular fractures. This study aims to evaluate the results in the management of such fractures. Thirty-two patients with fractures of posterior wall of acetabulum were reviewed retrospectively. The follow-up period was 7 (range 3–10) years. Twenty-four were associated with initial posterior dislocations. Twenty-seven were managed with open reduction and internal fixation, while the remainder were managed conservatively. Reductions were rated as congruent in 30 cases and as noncongruent in 2. The functional results were excellent in 16 cases, good in 10, fair in 2, and poor in 4. Two early complications were met, namely 1 iatrogenic sciatic nerve injury and 1 superficial wound infection. Sixteen late complications were noted, including 10 heterotopic ossifications, 3 avascular necroses of femoral head, and 3 symptomatic arthritides. The incidence of late complications was high, but the functional results were generally satisfactory. Congruent reduction was the key in obtaining satisfactory results in the management of these fractures.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00439052
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  • 9
    Electronic Resource
    Electronic Resource
    Scattering mechanisms of charge carriers in transparent conducting oxide films (1996)
    Springer
    Applied physics 62 (1996), S. 487-492 
    Details
    ISSN: 1432-0630
    Keywords: 73.50. - h ; 73.50.Bk ; 73.61.Ga
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract Scattering mechanisms of charge carriers in Transparent Conducting Oxide (TCO) films have been analyzed theoretically. For the degenerate polycrystalline TCO films with relatively large crystallite sizes and high carrier concentrations (higher than 5 × 1018 cm−3), the depletion layers between crystallites are very thin compared to the crystallite sizes, and the grain boundary scattering on electrical carriers makes a small contribution to limit the mobility of the films. Instead of thermionic emission current, a tunneling current dominates the electron transport over grain boundaries. The Petritz model which is based on thermionic emission and extensively quoted in literature should not be applicable. The main scattering mechanisms for the TCO films are ionized impurity scattering in the low-temperature range and lattice vibration scattering in the high-temperature range. The ionized impurity scattering mobility is independent of temperature and the mobility due to thermal lattice vibration scattering is inversely proportional to the temperature. The results obtained from Hall measurements on our ZnO, ITO, SnO2 and SnO2:F films prepared with various methods supports the analysis.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01567122
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  • 10
    Electronic Resource
    Electronic Resource
    Scattering mechanisms of charge carriers in transparent conducting oxide films (1996)
    Springer
    Applied physics 62 (1996), S. 487-492 
    Details
    ISSN: 1432-0630
    Keywords: PACS: 73.50. ; h; 73.50.Bk; 73.61.Ga
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract.  Scattering mechanisms of charge carriers in Transparent Conducting Oxide (TCO) films have been analyzed theoretically. For the degenerate polycrystalline TCO films with relatively large crystallite sizes and high carrier concentrations (higher than 5×1018 cm-3), the depletion layers between crystallites are very thin compared to the crystallite sizes, and the grain boundary scattering on electrical carriers makes a small contribution to limit the mobility of the films. Instead of thermionic emission current, a tunneling current dominates the electron transport over grain boundaries. The Petritz model which is based on thermionic emission and extensively quoted in literature should not be applicable. The main scattering mechanisms for the TCO films are ionized impurity scattering in the low-temperature range and lattice vibration scattering in the high-temperature range. The ionized impurity scattering mobility is independent of temperature and the mobility due to thermal lattice vibration scattering is inversely proportional to the temperature. The results obtained from Hall measurements on our ZnO, ITO, SnO2 and SnO2:F films prepared with various methods supports the analysis.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s003390050328
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