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  • 1
    Electronic Resource
    Electronic Resource
    Spectroscopic properties of nitrogen doped hydrogenated amorphous carbon films grown by radio frequency plasma-enhanced chemical vapor deposition (2001)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 89 (2001), S. 7924-7931 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Nitrogen doped hydrogenated amorphous carbon thin films have been deposited by rf plasma-enhanced chemical vapor deposition using CH4 as the source of carbon and with different nitrogen flow rates (N2/CH4 gas ratios between 0 and 3), at 300 K. The dependence modifications of the optical and the structural properties on nitrogen incorporation were investigated using different spectroscopic techniques, such as, Raman spectroscopy, Fourier transform infrared spectroscopy, x-ray photoelectron spectroscopy, ultraviolet-visible (UV-VIS) spectroscopy, electron spin resonance (ESR), photoluminescence (PL) and spectroscopic ellipsometry (SE). Raman spectroscopy and IR absorption reveal an increase in sp2-bonded carbon or a change in sp2 domain size with increasing nitrogen flow rate. It is found that the configuration of nitrogen atoms incorporated into an amorphous carbon network gradually changes from nitrogen atoms surrounded by three (σ bonded) to two (π bonded) neighboring carbons with increasing nitrogen flow rate. Tauc optical gap is reduced from 2.6 to 2.0 eV, and the ESR spin density and the peak-to-peak linewidth increase sharply with increasing nitrogen flow rate. Excellent agreement has been found between the measured SE data and modeled spectra, in which an empirical dielectric function of amorphous materials and a linear void distribution along the thickness have been assumed. The influence of nitrogen on the electronic density of states is explained based on the optical properties measured by UV-VIS and PL including nitrogen lone pair band. © 2001 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1371268
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  • 2
    Electronic Resource
    Electronic Resource
    Characterization and in situ monitoring of a novel compact electron cyclotron resonance plasma source (1995)
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 66 (1995), S. 5252-5256 
    Details
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: For plasma-assisted processing of future semiconductor devices, a new compact electron cyclotron resonance (ECR) plasma source has been specifically designed. The source is novel in that the magnets required for the production of ECR plasma are movable even in vacuum, and in situ monitoring of the discharge zone is also possible. Typical plasma characteristics were evaluated for nitrogen gas using Langmuir probe diagnostics and ion energy analysis. The measured plasma parameters include electron densities in excess of 1010 cm−3 and low ion energies (〈30 eV) with narrow distributions, which can be easily controlled by varying the discharge pressure and downstream position. Moreover, changing the aperture size of the discharge cavity enables one to control the relative ratio of the ionic and atomic species in the plasma. In determining plasma stability, changes in plasma parameters after plasma start-up were investigated. The results show a correlation between changes in the plasma potential and the total plasma optical emission. In situ monitoring of the total plasma emission is suggested as a simple means of providing valuable information in real time about physical plasma parameter changes during processing. © 1995 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1146094
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  • 3
    Electronic Resource
    Electronic Resource
    Infection by human papillomavirus types 6, 11, 16, 18, 31, 33 and 35 of the cervix in Japanese women (1995)
    Suite 500, 5th Floor, 238 Main Street, Cambridge, Massachusetts 02142, USA : Blackwell Science Inc.
    International journal of gynecological cancer 5 (1995), S. 0 
    Details
    ISSN: 1525-1438
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Exfoliated cervical cells from 321 Japanese women were examined for human papillomavirus (HPV) DNA types 6, 11, 16, 18, 31, 33 and 35 using polymerase chain reaction (PCR) and dot-blot hybridization methods. HPV DNA was present in 9.3% of patients with normal cervixes, 72.7% of patients with cervical intraepithelial neoplasia (CIN) and 77.8% of patients with invasive carcinoma. Younger patients (〈inlineGraphic alt="leqslant R: less-than-or-eq, slant" extraInfo="nonStandardEntity" href="urn:x-wiley:1048891X:IJG05010045:les" location="les.gif"/〉29 years) with normal cervixes had a 18.5% incidence of HPV DNA, whilst similar older patients (〈inlineGraphic alt="geqslant R: gt-or-equal, slanted" extraInfo="nonStandardEntity" href="urn:x-wiley:1048891X:IJG05010045:ges" location="ges.gif"/〉50 years) had a 1.9% incidence, a significant difference (χ2= 6.478, P 〈 0.01). In the CIN I and II groups, an incidence of 11.1% of types 16 and 18 was found, while in the CIN III or invasive carcinoma group the incidence was 58.1%, again a significant difference (χ2 = 12.075, P 〈 0.01). Furthermore, persistence or progression of CIN showed a significant correlation with infections by types 16 and 33 (χ2= 4.904, P 〈 0.01). However, no significantly different incidence of HPV infection was found between the CIN and the invasive carcinoma groups. It is suggested that (a) younger patients with normal cervixes have a higher incidence of HPV infection than do older patients; (b) HPV types 16, 18 and 33 are important etiologic agents of CIN III and invasive carcinoma, as well as in the persistence and progression of CIN; (c) progression of CIN to invasive carcinoma may depend on factors other than HPV infection in the cervix.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1046/j.1525-1438.1995.05010045.x
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  • 4
    Electronic Resource
    Electronic Resource
    Synthesis and specific pressor activity of [1-aspartic acid, 5-valine, 9-serine]angiotensin I ("fowl and angiotensin I") (1977)
    s.l. : American Chemical Society
    Journal of medicinal chemistry 20 (1977), S. 315-316 
    Details
    ISSN: 1520-4804
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1021/jm00212a029
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  • 5
    Electronic Resource
    Electronic Resource
    Low density of defect states in hydrogenated amorphous carbon thin films grown by plasma-enhanced chemical vapor deposition (2001)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 78 (2001), S. 294-296 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The density of electronic defect states in most forms of amorphous carbon deposited at room temperature is found so far to be very high (1018–1022 spins cm−3). In this letter, we demonstrate that the radio-frequency plasma-enhanced chemical vapor deposited hydrogenated amorphous carbon (a-C:H) thin film exhibits the lowest spin density of the order of 1016 cm−3, investigated by using electron spin resonance (ESR) spectroscopy, a very promising reproducible result comparable with high-quality a-Si:H. In addition, the optical gap of a-C:H has been tailored between a wide range, 1.8–3.1 eV. The ESR spectra of all the films reveal a single Lorentzian line whose linewidth ΔHpp varies strongly with the optical gap. Also, there is a strong dependence of spin density on the optical gap, and we show that this dependency is a direct result of structural changes due to sp3/sp2 carbon bonding network. © 2001 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1335548
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  • 6
    Electronic Resource
    Electronic Resource
    Determination of optical properties of nitrogen-doped hydrogenated amorphous carbon films by spectroscopic ellipsometry (2001)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 78 (2001), S. 3962-3964 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Nitrogen-doped hydrogenated amorphous carbon films have been deposited on silicon substrates by radio-frequency plasma-enhanced chemical vapor deposition using different N2/CH4 gas ratios from 0 to 3. The real and imaginary parts, n and k, of the complex index of refraction of these films have been determined for wavelengths between 300 and 830 nm by spectroscopic ellipsometry. Excellent agreement has been found between measured and modeled spectra, in which an empirical dielectric function based on classical Lorentz oscillator and Tauc joint density of states, and a linear void distribution along the thickness of the films have been assumed. Decrease in the optical energy gap and increase in the extinction coefficient, k, with increase in nitrogen concentration have been observed. Refractive index, n, increases rapidly with increase in nitrogen concentration up to 6.8 at. % (∼7.0 at. %) and then increases slowly with further increase in nitrogen concentration. For all the samples, n is found to be highest at the film-substrate interface which gradually decreases towards the film surface. © 2001 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1374501
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  • 7
    Electronic Resource
    Electronic Resource
    Evaluation of diagonal earlobe crease as a marker of coronary artery disease: the use of this sign in pre-operative assessment* (2001)
    Oxford, UK : Blackwell Science Ltd
    Anaesthesia 56 (2001), S. 0 
    Details
    ISSN: 1365-2044
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: In this study, we examined the usefulness of the earlobe crease sign as a marker of coronary artery disease in the pre-operative assessment of patients. We were interested in evaluating this sign for use in emergency patients. We investigated 530 patients, aged 〉 40 years, undergoing elective surgery. If the electrocardiogram was abnormal or the patient reported symptoms suggesting coronary artery disease, further cardiac examinations were performed. Patients who demonstrated evidence of coronary artery disease in the additional investigations or had a clear history of coronary artery disease were classified as the abnormal coronary group. Other patients with no history and/or normal investigations were classified as the normal coronary group. The assessment of earlobe crease sign was performed prior to anaesthesia, and the sensitivity, specificity and positive predictive value of this sign were calculated. We found that the sensitivity and specificity was high regardless of age, except for specificity in patients 〉 70 years old. The data suggest that the earlobe crease sign may be a useful marker for the presence of coronary artery disease in patients undergoing emergency operations in which little or no history and investigations are available. However, more work is required to assess the use of this sign in other ethnic groups.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1365-2044.2001.02317.x
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  • 8
    Electronic Resource
    Electronic Resource
    Regulational Effect of Ghrelin on Growth Hormone Secretion from Perifused Rat Anterior Pituitary Cells (2002)
    Oxford, UK : Blackwell Science, Ltd
    Journal of neuroendocrinology 14 (2002), S. 0 
    Details
    ISSN: 1365-2826
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Ghrelin, a novel growth hormone (GH)-releasing peptide, was recently isolated from the rat stomach as an endogenous ligand to growth hormone secretagogue receptor (GHS-R). Ghrelin specifically stimulates the release of GH from the rat anterior pituitary gland, but the regulational effect of ghrelin on GH secretion has not yet been clarified. We used a perifusion system to examine the single effect and combined effects of ghrelin with growth hormone-releasing hormone (GHRH) and somatostatin on GH secretion from rat anterior pituitary cells. The increase in GH concentration due to ghrelin stimulation showed a transitory peak that was almost the same as that previously reported for GHS, but apparently distinct from that of GHRH. Ghrelin (10−10 M to 10−8 M) stimulated GH secretion from the rat anterior pituitary cells in a dose-dependent manner. Serial ghrelin stimulation of the dispersed cells at 1-h intervals decreased the GH response, but the response recovered with stimulation at 3-h intervals, indicating that ghrelin strongly desensitized cells. Costimulation with ghrelin and GHRH elicited neither a synergistic nor an additive GH response from the rat pituitary cells. Furthermore, pretreatment to anterior pituitary cells with somatostatin strongly abolished ghrelin- and/or GHRH-stimulated GH secretion. In this study, we demonstrated that ghrelin caused weaker GH secretion than that caused by GHRH, and we also showed that costimulation with GHRH had no additive or synergistic effect on GH secretion, suggesting that ghrelin indirectly affects coordinated GH release from pituitary gland, as found in vivo.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1046/j.0007-1331.2001.00757.x
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  • 9
    Electronic Resource
    Electronic Resource
    The Structure of the Masseter Muscle in the Giraffe (Giraffa camelopardalis) (2001)
    Oxford UK : Blackwell Science Ltd.
    Anatomia, histologia, embryologia 30 (2001), S. 0 
    Details
    ISSN: 1439-0264
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: In the giraffe (Giraffa camelopardalis), the masseter muscle was divided into several layers. The superficial and more medial (second) tendinous sheets of the masseter muscle fused with each other at the dorso-caudal part and a fleshy portion was located between these tendinous sheets. In the rostral part, the most superficial tendinous sheet turned around as a compact tendon and attached to the facial crest (Crista facialis). The turned tendinous sheet, however, never fused with the second tendinous sheet and this layer of the masseter muscle, that originated from the facial crest with the turned sheet, was inserted into the mandible with its fleshy portion. In the cattle, goat, sheep and Sika deer, the rostral layer of the masseter muscle arises from the facial crest with its fleshy portion and is inserted into the tubercle on the mandible through the strong tendinous sheet. In this study, the takin also showed the same structure of the masseter muscle. In the giraffe, however, the rostral layer inserted into the mandible through the strong tendinous sheet could not be distinguished, thus, there was no conspicuous tubercle on the mandible. Moreover in the masseteric region of the skull, the giraffe was similar to the Sika deer in several ways. However, it is suggested that the giraffe exerts smaller forces on the cheek teeth than does the Sika deer because of its longer Margo interalveolaris.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1046/j.1439-0264.2001.00342.x
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  • 10
    Electronic Resource
    Electronic Resource
    Peculiar Bundles of Filaments in Leydig Cells of the Lesser Mouse Deer (Tragulus javanicus): an Ultrastructural Study (2003)
    Berlin, Germany : Blackwell Verlag GmbH
    Anatomia, histologia, embryologia 32 (2003), S. 0 
    Details
    ISSN: 1439-0264
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Leydig cells of lesser mouse deer (Tragulus javanicus) testes were observed using light and transmission electron microscopies. Sexually mature lesser mouse deer were obtained in East Malaysia. The testes were perfused with 5% glutaraldehyde, postfixed with 1% OsO4, dehydrated in ethanol and embedded in Araldite. The semithin sections were cut, stained with toluidine blue and observed under light microscopy. The ultrathin sections were cut, stained with uranyl acetate and lead citrate, and examined using a JEM-1200 transmission electron microscope. As a result, two types of filament bundles were frequently recognized in Leydig cells, but not in other testicular cells. These bundles were clearly seen at even a light microscopic level. One type was bundles of actin filaments (approximately 5 nm in diameter). These structures were found not only in the cytoplasm but also in the nucleus. The other type was bundles of intermediate filaments (approximately 10 nm in diameter). These structures were found only in the cytoplasm. The existence of filament bundles has never been reported in the testicular cells of another mammalian species. Thus, while bundles of actin and intermediate filaments are specifically present in the Leydig cells of the lesser mouse deer, their functions are still unclear.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1439-0264.2003.00499.x
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