In June 2009, 22 spectrometers from 14 institutes measured tropospheric and stratospheric NO2 from the ground for more than 11 days during the Cabauw Intercomparison Campaign of Nitrogen Dioxide ...measuring Instruments (CINDI), at Cabauw, NL (51.97° N, 4.93° E). All visible instruments used a common wavelength range and set of cross sections for the spectral analysis. Most of the instruments were of the multi-axis design with analysis by differential spectroscopy software (MAX-DOAS), whose non-zenith slant columns were compared by examining slopes of their least-squares straight line fits to mean values of a selection of instruments, after taking 30-min averages. Zenith slant columns near twilight were compared by fits to interpolated values of a reference instrument, then normalised by the mean of the slopes of the best instruments. For visible MAX-DOAS instruments, the means of the fitted slopes for NO2 and O4 of all except one instrument were within 10% of unity at almost all non-zenith elevations, and most were within 5%. Values for UV MAX-DOAS instruments were almost as good, being 12% and 7%, respectively. For visible instruments at zenith near twilight, the means of the fitted slopes of all instruments were within 5% of unity. This level of agreement is as good as that of previous intercomparisons, despite the site not being ideal for zenith twilight measurements. It bodes well for the future of measurements of tropospheric NO2 , as previous intercomparisons were only for zenith instruments focussing on stratospheric NO2 , with their longer heritage.
For several years NO2 and OClO, two species important to understanding ozone destruction in the Antarctic stratosphere, have been measured at Arrival Heights, Antarctica by two groups: New Zealand's ...National Institute of Water and Atmospheric Research (NIWA) and the NOAA Aeronomy Laboratory in Boulder, Colorado. Using data independently collected by these two groups during the Austral spring of 1996, it is shown that the two data sets are in extremely close agreement. Besides offering validation of the instrumentation and analysis techniques of both groups, this result provides confidence in the more complete history of these species gained by combining the two data sets.PUBLICATION ABSTRACT
Pulsed laser deposition (PLD) of YBa/sub 2/Cu/sub 3/O/sub 7-x/ (YBCO) thin films on both sides of 3-inch diameter sapphire wafers and LaAlO/sub 3/ (LAO) cylinder substrates, respectively, is a basic ...and flexible technique in order to optimize microwave bandpass filters for wireless communication systems. The large-area and double-side PLD technique allows homogeneous and reproducible YBCO deposition on both substrate sides with inductively measured critical current densities j/sub c/ of 3/spl times/10/sup 6/ to 5/spl times/10/sup 6/ A/cm/sup 2/ at 77 K with a YBCO thickness of 350 nm to 600 nm. Selected results of compositional, structural, electrical, and microwave characterization of the PLD-YBCO films are reported.
To determine the frequency of occult right heart thromboembolism during endomyocardial biopsy, 51 cardiac transplant recipients undergoing routine endomyocardial biopsy were studied ...echocardiographically. Patients were randomized to two groups. In Group 1, the venous sheath was flushed between each biopsy attempt; in Group 2, it was flushed only at the time of initial placement.
Right heart thromboemboli were identified in 18 (35%) of 51 patients. Seventeen (94%) of these 18 patients were in Group 2. Patients requiring more than six biopsy attempts had a signifi- cantly higher incidence of embolism. Other variables such as antiplatelet therapy, operator experience and total time of the procedure did not correlate with occurrence of thrombus. All right heart emboli were asymptomatic.
These data demonstrate a high incidence of occult pulmonary embolism during uncomplicated routine endomyocardial biopsy. Meticulous flushing of the introducer sheath significantly reduces the incidence of thrombus formation in intravenous sheaths.
In June 2009, 22 spectrometers from 14 institutes measured tropospheric and stratospheric NO2 from the ground for more than 11 days during the Cabauw Intercomparison Campaign of Nitrogen Dioxide ...measuring Instruments (CINDI), at Cabauw, NL (51.97° N, 4.93° E). All visible instruments used a common wavelength range and set of cross sections for the spectral analysis. Most of the instruments were of the multi-axis design with analysis by differential spectroscopy software (MAX-DOAS), whose non-zenith slant columns were compared by examining slopes of their least-squares straight line fits to mean values of a selection of instruments, after taking 30-min averages. Zenith slant columns near twilight were compared by fits to interpolated values of a reference instrument, then normalised by the mean of the slopes of the best instruments. For visible MAX-DOAS instruments, the means of the fitted slopes for NO2 and O4 of all except one instrument were within 10% of unity at almost all non-zenith elevations, and most were within 5%. Values for UV MAX-DOAS instruments were almost as good, being 12% and 7%, respectively. For visible instruments at zenith near twilight, the means of the fitted slopes of all instruments were within 5% of unity. This level of agreement is as good as that of previous intercomparisons, despite the site not being ideal for zenith twilight measurements. It bodes well for the future of measurements of tropospheric NO2, as previous intercomparisons were only for zenith instruments focussing on stratospheric NO2, with their longer heritage.
Within the framework of the Network for the Detection of Stratospheric Change (NDSC), an intercomparison campaign of ground‐based zenith‐sky viewing UV‐visible spectrometers was held at the Andøya ...Rocket Range (69°N, 16°E) at Andenes, Norway, from February 12 to March 8, 2003. The chosen site is classified as a complementary NDSC site. Eight groups from seven countries participated in the campaign which focused on the measurements of slant columns of NO
2
, BrO, and OClO. This first campaign publication concentrates on measurements of the NO
2
slant columns. Different analysis criteria were investigated during the campaign. These included the use of fitting parameters as chosen by each group to provide what they considered to be optimized retrievals. Additional sets of parameters, imposed for all the groups, were also used, including the wavelength interval, absorption cross sections, and species fitted. Each instrument's results were compared to the measurements of selected reference instruments, whose choice was based on a technique combining regression analysis and examination of the residuals with solar zenith angle. Considering the data obtained during the whole campaign for solar zenith angles between 75° and 95°, all instruments agreed within 5% in the case of NO
2
with imposed analysis parameters in the 425–450 nm region. Measurements agree less well when retrieving the NO
2
slant columns in the 400–418 nm region or when using parameters optimized by each investigator for their instrument.
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