The application of a vacuum ultraviolet Fourier transform spectrometer and synchrotron radiation source to measurements of: IV. The β(6,0) and γ(3,0) bands of NO

The β(6,0) and the γ(3,0) bands of NO near 198 nm were analyzed using the VUV FT spectrometer with synchrotron radiation for the background source. Accurate line positions and line strengths of the rotational lines were retrieved from the FT spectra. The rotational term values of the B 2∏ r (v=6) and A 2Σ + (v=3) levels were evaluated and fed to a least squares fitting program to obtain accurate molecular constants of these levels.published_or_final_versio

Application of a VUV fourier transform spectrometer and synchrotron radiation source to measurements of. VI. The ε(0,0) band of NO

The analysis of the ε(0,0) band around 187.6 nm was reported using the VUV FTS with synchrotron radiation for the background source. Due to the capability of the combintion of instruments, These were the first high-resolution quantitative measurements of line positions and intensities of the rotational lines of the ε(0,0) band. The determination of the band oscillator strengths of the band was performed using line-by-line measurements, because the resolution of the present experiment was comparable to the Doppler widths.published_or_final_versio

The application of a VUV Fourier transform spectrometer and synchrotron radiation source to measurements of: I. the β(9,0) band of NO

State-of-the-art models of the vacuum ultraviolet (VUV) absorbing properties of the atmosphere call for absorption cross sections with detail on the scale of the Doppler widths. As a consequence, spectroscopic data at resolving powers of the order of 10 6 are needed. To meet these requirements in the vacuum ultraviolet region, we have used the VUV Fourier transform spectrometer from Imperial College, London, at the synchrotron radiation facility at Photon Factory, KEK, Japan, to measure photoabsorption cross sections of NO from 195 to 160 nm, and of O 2 from 185 to 175 nm. The analysis of the β(9,0) band (B 2Π r-X 2Π r) of NO provides accurate rotational line positions and term values. Molecular constants of the B(9) 2Π level are T 0=54205.097±0.012cm -1, A=45.320±0.021cm -1, B υ=1.01672±0.00016cm -1, D υ=(10.61±0.32)×10 -6cm -1, and A D=0.00122±0.00011cm -1. The rotational line strengths and the branching ratios are also presented. The band oscillator strength is obtained as f=2.65×10 -4. © 1998 American Institute of Physics.published_or_final_versio

A2Σ+–X2Π Bands of18OD

The emission spectrum of the A 2Σ +-X 2Π (0, 0), (1, 0), and (1, 1) bands of 18OD has been investigated with a 6.65-m vacuum spectrograph in the wavelength region 290 to 350 nm. The emission spectrum of 18OD was produced by microwave discharge of D 2 18O vapor. All 12 branches expected from a 2Σ- 2Π transition have been observed and assigned. A merged least-squares fit of the measured line positions yielded molecular parameters of the v = 0 and 1 levels of both A 2Σ + and X 2Π states. Excellent agreement has been obtained between determined molecular parameters and those calculated from isotopic relationships. © 1996 Academic Press, Inc.link_to_subscribed_fulltex

Periodontal status of adults with systemic sclerosis: Case-control study

Background: Systemic sclerosis (SSc) is a systemic autoimmune disease that affects connective tissue in the skin, blood vessels, and major organs of the body. This project aims to compare the periodontal status of dentate Hong Kong Chinese with and without SSc. Methods: Thirty-six non-smoking adults with SSc (one male and 35 females: aged 50.6 ± 11.7 years; free from Sjögren syndrome) attending a teaching hospital were age- and sex-matched to systemically healthy controls attendingadental hospital. Both groups had similar demographic characteristics but a lower proportion of patients with SSc were working or studying (P <0.05). Twenty-three (32%) of all participants were regular dental attendees. Orthopantomogram radiographs were taken. Participants were surveyed and periodontally examined. Results: Both groups hadasimilar numberoferupted teeth, proportion of sites with detectable plaque, and mean fullmouth clinical attachment level, whereas controls had less bleeding on probing (49.3% ± 22.6% versus 78.4% ± 19.6%; P <0.001) and a shallower mean full-mouth probing depth (1.92 ± 0.44 mm versus 2.52 ± 0.58 mm; P <0.001). Radiographically, patients with SSc had wider periodontal ligament spaces (0.36 ± 0.06 mm versus 0.33 ± 0.03 mm; P <0.01). Conclusions: Hong Kong Chinese adults with SSc seem to exhibit higher levels of periodontal inflammation and wider radiographic periodontal ligament spaces than age- and sexmatched controls. Future studies are warranted to further investigate any associations between these periodontal features and SSc.link_to_subscribed_fulltex

Perception of non-surgical periodontal treatment with or without local anesthesia

Conference Theme: We are the FuturePoster PresentationSession 22: P2Objective: Patients might refuse the offer of local anesthesia (LA) administration prior to dental treatment. This study investigates subjective discomfort perception during non-surgical mechanical periodontal therapy delivered with or without prior administration of LA. Method: Sixty mild-to-moderate chronic periodontitis patients were randomly enrolled to non-surgical therapy with or without LA administration. Patients were free to comply or not with the allocated treatment arrangement. Visual analogue scales (VAS) of discomfort perception at various stages of the treatment, plus overall satisfaction were recorded. Result: A total of 31 patients undergoing non-surgical periodontal therapy not receiving (LA-) and 29 subjects receiving (LA+) LA were studied. All patients had experienced periodontal debridement before. Compared to LA- subjects, LA+ individuals perceived less discomfort during treatment and reported less dental anxiety. Prior unpleasant periodontal experience was identified to be associated with lower perceived overall treatment satisfaction (P = 0.047). Overall, debridement discomfort was associated with not receiving LA, non-compliance with the pain control regimen allocated, greater gingival inflammation and higher percentage sites with probing pocket depths ≥5 mm (P < 0.05). Conclusion: Gingival inflammation, periodontal pocketing and not receiving LA, appeared to be associated with more perceived discomfort by mild-to-moderate periodontitis patients undergoing non-surgical periodontal treatment. Clinicians should be aware that subjects who refuse LA could have with higher dental anxiety and therefore may require various pain control strategies for comfort during non-surgical periodontal therapy, which if not employed in turn could lead to lower periodontal treatment satisfaction. This abstract is based on research that was funded entirely or partially by an outside source: Research Grants Council of the Hong Kong Special Administrative Region, China, HKU 772110

The application of a VUV-FT spectrometer and synchrotron radiation source to measurements of the NO and O2 bands at 295 K

Current research on the Earth's upper atmosphere requires molecular parameters of unprecedented detail and accuracy. Models of the vacuum-ultraviolet (VUV) absorbing properties of the atmosphere call for absorption cross sections with details on the scale of the Doppler linewidths. As a consequence, spectroscopic data at resolving powers of the order of 10 6 are needed. Current particular needs are for ultra high resolution absorption cross section data for some bands of NO and O 2 in the UV to VUV region. To meet these requirements, we moved the VUV Fourier transform spectrometer at Imperial College, London to a synchrotron radiation facility (Photon Factory, KEK, Japan) and measured VUV photoabsorption cross sections of NO from 195 to 160 nm and O 2 from 185 to 175 nm. (C) 2000 Elsevier Science Ltd. All rights reserved.link_to_subscribed_fulltex

High resolution absorption cross-section measurements of the Schumann-Runge bands of O2 by VUV Fourier transform spectroscopy

The photoabsorption spectrum of the O2 Schumann-Runge bands was measured with resolution comparable to the Doppler widths by using the VUV Fourier transform spectrometer from Imperial College, London, combined with synchrotron radiation as a continuum light source at the Photon Factory, KEK, Japan. The analysis of the (12,0)-(17,0) bands of the Schumann-Runge system provides accurate rotational line positions as well as the line intensities from 185 to 175 nm. Molecular constants of the v′ = 12 to 17 levels of the B 3σ - u state have been determined. The (v′, 0) band oscillator strengths were determined as 2.38, 2.62, 2.70, 2.66, 2.40, and 2.12 × 10 -5 for the bands from v′ = 12 to 17, respectively. © 2003 Elsevier Science (USA). All rights reserved.link_to_subscribed_fulltex