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  • 1
    Electronic Resource
    Electronic Resource
    Comparison between the calculated and measured energy transfer rates of the 4S3/2 state in Er3+-doped fluorozirconate glasses (2000)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 88 (2000), S. 1900-1906 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The dependence of the fluorescence lifetime of the 4S3/2 state of the Er3+ ion on the ErF3 concentration was measured in fluorozirconate glasses at room temperature. Energy transfer rates were calculated from optical parameters assuming that the Er3+ ions in fluorozirconate glasses were dispersed as the cubic, bcc, or fcc structure, and were inserted into the rate equation. The dependence of the total transition rate of the 4S3/2 state of the Er3+ ion on the ErF3 concentration was calculated by using the rate equation and compared with the total transition rate measured by the lifetime experiment. Although many studies have reported the energy transfer rates in various rare-earth ions, the reliability of the calculated energy transfer rates has been hardly discussed. The energy transfer rate can be derived from the total transition rate. The energy transfer rate estimated from the rate equation calculation was compared with the energy transfer rate obtained from the lifetime measurement. It could be shown that the calculated energy transfer rate assuming that the Er3+ ions were dispersed as the cubic structure was closer to the measured energy transfer rate than that as the bcc and fcc structures. With increasing the ErF3 concentration, the calculated energy transfer rate when the Er3+ ions were dispersed as the cubic structure was comparable to the measured energy transfer rate. It was suggested that at the lower concentration of ErF3 (≤2 mol %), we needed to use the distance between Er3+ ions which was shorter than that as the cubic structure in the calculation of the energy transfer rate. © 2000 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1303742
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  • 2
    Electronic Resource
    Electronic Resource
    Upconversion mechanism in Er3+-doped fluorozirconate glasses under 800 nm excitation (1999)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 85 (1999), S. 29-37 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The upconversion emission intensities of Er3+ ion around 550 and 660 nm in fluorozirconate glasses were measured under 800 nm excitation. Though energy transfer processes played an important role in upconversion mechanism at high concentration of ErF3, those have not been treated quantitatively. The energy transfer rates were calculated from the optical parameters assuming some distribution of Er3+ ions. We calculated the upconversion intensities around 550 and 660 nm by using rate equations. It was found that the dependence of upconversion emission intensities on the ErF3 concentration could be reproducible and the principal upconversion mechanism could be evaluated. © 1999 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.369445
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  • 3
    Electronic Resource
    Electronic Resource
    S-IV-05 
Study in Hybridized Tissue Engineered Trachea by Using Acellular Trachea Scaffold (2004)
    Oxford, UK; Malden, USA : Blackwell Science Inc
    Wound repair and regeneration 12 (2004), S. 0 
    Details
    ISSN: 1524-475X
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Aim: A method for preparing acellular trachea scaffold and its effectiveness were investigated by using rabbits and dogs Methods: The sacrificed dog or rabbit trachea was collected. The spiral stent of stainless steel was inserted in the obtained trachea. To remove all of cellular components in tissues, the trachea was rinsed with sterilized 0.5% Triton X-100 for 24 to 48 hours at ambient temperature and then for removing the detergents completely using fresh water. The acellular trachea obtained was lyophilized and sterilized by ethylene oxide gas. Before implantation, the lyophilized acellular trachea was soaked in phosphate buffered saline containing 0.5% gelatin and other adhesive molecules for 2 to 18 hours at 37 degree. After 15 mm of rabbit neck trachea was removed surgically under anesthesia, the same length of reengorged acellular rabbit trachea was implanted the removed region. In the case of dog, 50 mm of thoracic trachea was removed under the mechanical ventilation and then the same length of reengorged acellular trachea was implanted by technique of end to end anastomosis. The implanted trachea was rapped by omentum. The effectiveness of acellualr scaffold on implanted-animals was evaluated by endoscope finding. Results: 1) The rabbits implanted reengorged-acellular trachea survived for minimum 10 days and maximum 60 days. It was suggested that the cause of death was the infection of implantation region. 2) The dog implanted reengorged-acellular trachea survived for over 60 days at least. The cause of death was strangulated hernia. 3) The acellular trachea containing various growth factors or cultured with fibroblasts was not always effective. Discussion: It is not necessary for the animal implanted acellular trachea to be administered the immunodepressants such as the animal implanted cryopreserved trachea. From these results, the tissue engineered acellular trachea may be more effective than the cryopreserved trachea.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1067-1927.2004.abstractm.x
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  • 4
    Electronic Resource
    Electronic Resource
    Breakdown and destruction of heterogeneous solid dielectrics by high voltage pulses (1998)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 84 (1998), S. 6262-6267 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: A mechanism explaining the breakdown of dielectrics with high intrinsic inhomogeneity like natural rocks and concrete is proposed and proved experimentally. This work has a very promising industrial application in the drilling and demolition of natural and artificial solid materials by electric pulses. The mechanism includes the breakdown of gas cavities inside the dielectric and on its surface. At a very high applied voltage, the high electric field causes the breakdown in the cavities. The displacement and conduction currents flowing through a number of such cavities result in the heating of the plasma and high pressure pulse generation. The pulsed pressure results in crack formation and finally, in the destruction of a solid material. © 1998 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.368946
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  • 5
    Electronic Resource
    Electronic Resource
    Effect of Yb3+ doping on upconversion emission intensity and mechanism in Er3+/Yb3+-codoped fluorozirconate glasses under 800 nm excitation (1999)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 86 (1999), S. 6143-6149 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Er3+ singly- and Er3+/Yb3+-codoped fluorozirconate glasses were prepared. The upconversion emission intensities of the Er3+ ion around both 550 and 660 nm were measured under 800 nm excitation. The absorption band of the Yb3+ ion is located around 980 nm. Though the absorption band of Yb3+ does not interact directly with the incident light at 800 nm, both upconversion intensities around 550 and 660 nm emission increased with the increasing YbF3 concentration. We calculated the upconversion intensities around 550 and 660 nm by using rate equations and evaluated the principal upconversion mechanism in Er3+ singly- and Er3+/Yb3+-codoped samples quantitatively. We also investigated the reason for the increase of the upconversion emission intensities with the codoping of Yb3+ under 800 nm excitation. © 1999 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.371666
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  • 6
    Electronic Resource
    Electronic Resource
    Method of producing tissue sections from endometrial scrapings (2002)
    Oxford UK : Blackwell Science Ltd.
    Cytopathology 13 (2002), S. 0 
    Details
    ISSN: 1365-2303
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Method of producing tissue sections from endometrial scrapings Endometrial cytology is important not only for observing cytological findings, but also for assessing histological architecture. Therefore, we attempted to produce a histological preparation from the sample using an automatic fixation apparatus (ACF 1000) which employs a membrane filter method.After observation of the cytological features, the cover slip was removed and a paraffin-embedded section was prepared.Producing a histological section from a cytological specimen prepared with the ACF 1000 apparatus was more useful and easier than with the techniques described to date. Peelability of the cell was avoided by using a silane-coated membrane filter. Observation of the same cell cluster as that observed in the cytological sample was also facilitated in the histological section by this technique.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1046/j.1365-2303.2002.00364.x
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  • 7
    Electronic Resource
    Electronic Resource
    Electromyographic study of the activity of jaw depressor muscles before initiation of opening movements (1999)
    Oxford, UK : Blackwell Science Ltd
    Journal of oral rehabilitation 26 (1999), S. 0 
    Details
    ISSN: 1365-2842
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: The authors attempted to clarify the primary factors affecting the timing of the initial electromyographic discharges in the jaw depressor muscles (EMG onset). The changes in EMG onset in the inferior head of the lateral pterygoid (Lpt) and the anterior belly of the digastric muscles (Dig) were measured by varying duration of the open–close movement or occlusal force during the open–close–clench cycle (OCC). EMG onset tended to precede the beginning of the opening movement during OCC. The duration of opening and closing phase and the duration of occluding phase showed no significant correlation with the time-lag between EMG onset and the beginning of the opening movement (onset time).The mean EMG activity of the masseter muscle (Mm), corresponding to the occlusal force, showed a highly significant correlation with the onset time. The maximal opening velocity was highly correlated with the mean EMG activity of the jaw depressors before jaw opening. In conclusion, it was found that occlusal force is a major factor in EMG onset in the jaw depressors. It is suggested that smooth opening needs tooth contact with some degree of occlusal force.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1046/j.1365-2842.1999.00401.x
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  • 8
    Electronic Resource
    Electronic Resource
    Manometric and hormonal changes after distal partial gastrectomy (2000)
    Oxford, UK : Blackwell Science Ltd
    Alimentary pharmacology & therapeutics 14 (2000), S. 0 
    Details
    ISSN: 1365-2036
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Background: Alkaline oesophagitis attributable to duodenal mechanisms may induce oesophageal carcinogenesis in a rat reflux model. Aim: To investigate the mechanism of the regurgitation after distal partial gastrectomy. Methods: Oesophageal manometry was used in 16 patients before and after distal partial gastrectomy with reconstruction by Bilroth methods. Serum concentrations of four gastrointestinal hormones were measured by radioimmunoassay in 10 gastrectomy patients and nine healthy volunteers before and after a standardized meal. Results: The lower oesophageal sphincter pressure was reduced to 83% after surgery. The amplitude and duration of the peristaltic waves tended to be increased, and the velocity tended to be less after surgery (amplitude 120%, duration 114%, velocity 88%). Interrupted waves appeared more frequently after surgery. The manometric changes in gastrectomized patients are considered to be disadvantageous relative to regurgitation. After surgery, gastrin and pancreatic polypeptide were completely abolished postprandially, whereas cholecystokinin and neurotensin were significantly increased. Conclusion: The hormonal changes should have a suppressive effect on the lower oesophageal sphincter. Both the manometric and the hormonal changes may exacerbate reflux oesophagitis after distal partial gastrectomy.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1046/j.1365-2036.2000.014s1166.x
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  • 9
    Electronic Resource
    Electronic Resource
    Dichlorobis[4,4,5,5-tetramethyl-2-(2-pyridyl)-4,5-dihydro-1H-imidazol-1-yloxy 3-oxide]copper(II) Bis(dichloromethane) Solvate (1997)
    Oxford [u.a.] : International Union of Crystallography (IUCr)
    Acta crystallographica 53 (1997), S. 0-0 
    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/S0108270197099538
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  • 10
    Electronic Resource
    Electronic Resource
    Gravitationally redshifted emission implying an accretion disk and massive black hole in the active galaxy MCG63015 (1995)
    [s.l.] : Nature Publishing Group
    Nature 375 (1995), S. 659-661 
    Details
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] Recent optical and radio observations2 4 of gas motions show a large, central concentration of mass (probably a black hole) in a number of galaxies. But this gas lies beyond ~30,000 Schwarzschild radii so the characteristic signatures of the black hole itself-relativistic ...
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1038/375659a0
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