The Improved Limb Atmospheric Spectrometer (ILAS), a sensor for stratospheric ozone layer observation using a solar occultation technique, was mounted on the Advanced Earth Observing Satellite (ADEOS), which was put into a Sun‐synchronous polar orbit in August 1996. Operational measurements were recorded over high‐latitude regions from November 1996 to June 1997. This paper describes the data processing algorithm of Version 5.20 used to retrieve vertical profiles of gases such as ozone, nitric acid, nitrogen dioxide, nitrous oxide, methane, and water vapor from the infrared spectral measurements of ILAS. To simultaneously derive mixing ratios of individual gas species as a function of altitude, the nonlinear least squares method was utilized for spectral fitting, and the onion peeling method was applied to perform vertical profiling. This paper also discusses in detail estimation of errors (internal and external errors) associated with the derived gas profiles and compares the errors with repeatability. The internal error estimated from residuals in spectral fitting was generally larger than the repeatability, which suggests either that some unknown factors have not been incorporated into the forward model for simulating observed transmittance data or that some parameters in the model are inaccurate. The external error was almost comparable in magnitude to the repeatability. Numerical simulations were carried out to investigate performance of the nongaseous correction technique. The results showed that the background level of sulfuric acid aerosols has little effect on the retrieved profiles, while polar stratospheric clouds (PSCs) with extinction coefficients of the order of 10−3 km−1 at a wavelength of 780 nm have nonnegligible effects on the profiles of some gas species. Despite the problems that require further investigations, it is shown that the ILAS Version 5.20 algorithm generates scientifically useful products.
The Halogen Occultation Experiment (HALOE) experiment on Upper Atmosphere Research Satellite (UARS) performs solar occultation (sunrise and sunset) measurements to infer the composition and structure of the stratosphere and mesosphere. Two of the HALOE channels, centered at 5.26 gm and 6.25 gm, are designed to infer concentrations of nitric oxide and nitrogen dioxide respectively. The NO measurements extend from the lower stratosphere up to 130 km, while the NO2 results typically range from the lower stratosphere to 50 km and higher near the winter terminator. Comparison with results from various instruments are presented, including satellite-, balloon-, and ground-based measurements. Both NO and NO2 can show large percentage errors in the presence of heavy aerosol concentrations, confined to below 25 km and before 1993. The NO2 measurements show mean differences with correlative measurements of about 10 to 15% over the middle stratosphere. The NO2 precision is about 7.5x10 '13 arm, degrading to 2x10 -12 arm in the lower stratosphere. The NO differences are similar in the middle stratosphere but sometimes show a low bias (as much as 35%) between 30 and 60 km with some correlative measurements. NO precision when expressed in units of density is nearly constant at lx10 '12 atmospheres, or approximately 0.1 ppbv at 10.0 mb or, 1.0 ppbv at 1.0 mb, and so forth when expressed in mixing ratio. Above 65 km, agreement in the mean with Atmospheric Trace Molecule Spectroscopy (ATMOS) NO results is very good, typically + 15%. Model comparisons are also presented, showing good agreement with both expected morphology and diurnal behavior for both NO2 and NO. hydrogen chloride (HCI), hydrogen fluoride (HF), methane (CH4), water vapor (H20), nitric oxide (NO), nitrogen dioxide (NOy), and aerosol extinction. Retrieved profiles cover an altitude range from the upper troposphere, in some cases, to the lower thermosphere for nitric oxide. Fifteen spacecraft sunrises and sunsets are observed daily and usually in opposite hemispheres, although at certain times these measurements occur on the same day and almost overlap in space. Details of the HALOE experiment, including geographic coverage, discussion of the experiment and instrument techniques, instrument ground test results, error mechanisms, in-orbit performance, initial pressure versus latitude cross sections, and orthographic projections are included in the HALOE overview by Russell et. al. [1993]. The purpose of 'this paper is to describe steps taken and 'the status of efforts to validate data from the NO gas correlation channel and the NO2 radiometer channel. All results were inferred using the most current archived HALOE data, version 17, released in November 1994. Version numbers were liberally changed during the continuous validation and evolution of the HALOE processing system. Attainment of research quality results coincided with version 16 in late summer of 1994, which was the first version released to the general science community. However, a second general processing ...
Diclofenac sodium (Dc) was found to possess antibacterial activity against both drug-sensitive and drug-resistant clinical isolates of Staphylococcus aureus, Listeria monocytogenes, Escherichia coli, and Mycobacterium spp., in addition to its potent anti-inflammatory activity. The time-kill curve study indicates that this non-steroidal drug exhibits bactericidal activity against Listeria, E. coli, and M. tuberculosis. The antibacterial activity of Dc comes, in part, from its ability to inhibit the DNA synthesis of E. coli and L. monocytogenes. Dc could protect murine listeriosis, salmonellosis, and tuberculosis at doses ranged within its maximum recommended human or non-toxic ex-vivo dose. Dc possesses anti-plasmid activity and acts as a 'helper compound' in synergistic combination with streptomycin against E. coli and Mycobacterium or gentamicin against Listeria. This review focuses on the possible use of Dc, a non-antibiotic helper compound, in infections and inflammatory conditions, rationalized on the basis of the activities of the compounds.
Since 1993, massive mortalities have occurred among the penaeid shrimp Penaeus orientalis cultured in Korea. The major gross findings of the naturally occurring cases were 2 to 6 mm sized white spots on the inside of the carapace and reddish discolorization. Amphophilic to basophillc intranuclear inclusion bodies were readily observed in the epithelia of epidermis, foregut, gills, and lymphoid organs Electron microscopy revealed enveloped and nonoccluded ellipsoid to rod-shaped virus particles within the nucleus of lymphoid organ cells and the interstitial cells of the hepatopancreas of both naturally and experimentally infected shrimp. The size of the virions was 375 X 167 nm and the nucleocapsid was 290 X 75 nm. The agent which caused ectodermal and mesodermal necrosis in penaeid shrimp in Korea resembled white spot syndrome virus (WSSV) found in T a~w a n with respect to gross signs, histological changes and v~r a l morphology. Its viral morphology differed from that of the rod-shaped nuclear virus of Penaeus japonicus (RV-PJ) found in Japan However, a 643 bp PCR product with an identical sequence to that from RV-PJ was detected. The results suggested that the Korean agent combined characters descnbed for WSSV and RV-PJ.
Vertical profiles of water vapor concentration at high latitudes (57–72°N; 64–89°S) were observed by the Improved Limb Atmospheric Spectrometer (ILAS) solar occultation sensor aboard the Advanced Earth Observing Satellite (ADEOS). These measurements were made continuously from November 1996 through June 1997 with some additional periods in September to October 1996. A validation study of the water vapor data processed with the version 5.20 ILAS retrieval algorithm is presented in this paper. Uncertainty and general characteristics of the ILAS water vapor measurements are briefly reviewed. Comparisons are made with data obtained by (1) the ILAS validation balloon campaigns at Kiruna, Sweden and at Fairbanks, Alaska; (2) the aircraft measurements under the Photochemistry of Ozone Loss in the Arctic Region in Summer (POLARIS) campaign; and (3) available satellite measurements of the version 19 Halogen Occultation Experiment (HALOE) and the version 6 Stratospheric Aerosol and Gas Experiment II (SAGE II). The agreement between ILAS water vapor and all independent reliable correlative measurements in the altitude region of 15–60 km is better than 10% for the majority of cases and better than 20% for all comparisons, with the exception of some isolated cases detailed in this paper. Climatological comparisons of ILAS data with Upper Atmosphere Research Satellite (UARS) climatology and HALOE data show the overall consistency of ILAS water vapor data considering the known features of atmospheric circulation. The characteristics of ILAS measurements, i.e., high sampling frequency in polar latitudes with high vertical resolution along with the good data quality, make the ILAS water vapor data set valuable for various polar stratospheric research applications.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.