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Takayuki Ezaki - One of the best experts on this subject based on the ideXlab platform.
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rothia aeria sp nov rhodococcus baikonurensis sp nov and arthrobacter russicus sp nov isolated from air in the russian Space Laboratory mir
International Journal of Systematic and Evolutionary Microbiology, 2004Co-Authors: Ying Li, Xinxiang Huang, Nagatoshi Fujiwara, Takashi Naka, Kazuo Kobayashi, Yoshiaki Kawamura, Takayuki EzakiAbstract:Four Gram-positive bacteria, strains A1-17BT, A1-22T, A1-3T and A1-8, isolated from the air in the Russian Space Laboratory Mir, were subjected to a polyphasic taxonomic study. Phylogenetic analysis of the bacteria based on their 16S rDNA sequence showed that they belong to the genera Rothia (A1-17BT), Rhodococcus (A1-22T) and Arthrobacter (A1-3T and A1-8). Morphological, physiological, chemotaxonomic and genomic characteristics supported the assignments of these strains to these genera, but they could not be classified as any existing species within each respective genus. 16S rDNA similarity values between strain A1-17BT and its neighbours, Rothia dentocariosa genomovar II, Rothia dentocariosa, Rothia mucilaginosa and Rothia nasimurium, were respectively 99·8, 98·0, 96·4 and 95·4 %. Polyphasic taxonomic evidence indicated that strain A1-17BT should be categorized together with the unofficially named Rothia dentocariosa genomovar II, but clearly differentiated them from the established species of the genus Rothia. Strain A1-22T formed a coherent cluster with Rhodococcus erythropolis, Rhodococcus globerulus, Rhodococcus marinonascens and Rhodococcus percolatus in 16S rDNA sequence analysis, but DNA–DNA relatedness values were only 45·5, 35·3, 18·9 and 21·9 %. Strains A1-3T and A1-8 shared 99·9 % 16S rDNA sequence similarity, and strain A1-3T showed the highest level of 16S rDNA similarity, 96·6 %, to Arthrobacter polychromogenes. Contrasting biochemical characteristics were also identified. Finally, as a result of the polyphasic taxonomic study, three of the strains are proposed as type strains of novel species: Rothia aeria sp. nov. (A1-17BT=GTC 867T=JCM 11412T=DSM 14556T), Rhodococcus baikonurensis sp. nov. (A1-22T=GTC 1041T=JCM 11411T=DSM 44587T) and Arthrobacter russicus sp. nov. (A1-3T=GTC 863T=JCM 11414T=DSM 14555T).
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sphingomonas yabuuchiae sp nov and brevundimonas nasdae sp nov isolated from the russian Space Laboratory mir
International Journal of Systematic and Evolutionary Microbiology, 2004Co-Authors: Yoshiaki Kawamura, Xinxiang Huang, Nagatoshi Fujiwara, Takashi Naka, Kazuo Kobayashi, Hongsheng Liu, Takayuki EzakiAbstract:On the basis of phenotypic and genotypic characteristics and 16S rRNA gene sequence analysis, novel species belonging to the genera Sphingomonas and Brevundimonas were identified from samples taken from the Russian Space Laboratory Mir. Strain A1-18T was isolated from the air. 16S rDNA sequence analysis showed that strain A1-18T formed a coherent cluster with Sphingomonas sanguinis, Sphingomonas parapaucimobilis, Sphingomonas paucimobilis and Sphingomonas roseiflava with sequence similarity of 97·5–98·6 %. Similar to other Sphingomonas species, the G+C content was 66·1 mol%, but DNA–DNA hybridization rates at optimal temperatures among these related species were only 24·7–51·7 %. Strain A1-18T can be differentiated biochemically from related species. Strain W1-2BT was isolated from condensation water. It forms a distinct lineage within the genus Brevundimonas, forming a coherent cluster with Brevundimonas vesicularis, Brevundimonas aurantiaca and Brevundimonas intermedia. 16S rDNA sequence similarities were 98·6–99·5 % and the G+C content was 66·5 mol%, similar to other Brevundimonas species, but DNA–DNA relatedness was only 50·2–54·8 %. Strain W1-2BT also showed some differential biochemical properties from its related species. A series of polyphasic taxonomic studies led to the proposal of two novel species, Sphingomonas yabuuchiae sp. nov. (type strain A1-18T=GTC 868T=JCM 11416T=DSM 14562T) and Brevundimonas nasdae sp. nov. (type strain W1-2BT=GTC 1043T=JCM 11415T=DSM 14572T).
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chryseobacterium miricola sp nov a novel species isolated from condensation water of Space station mir
Systematic and Applied Microbiology, 2003Co-Authors: Yoshiaki Kawamura, Xinxiang Huang, Nagatoshi Fujiwara, Takashi Naka, Kazuo Kobayashi, Hongsheng Liu, Takayuki EzakiAbstract:Classification of strain W3-B1, which was isolated from condensation water in the Russian Space Laboratory Mir, was investigated by a polyphasic taxonomic approach. Cells of strain W3-B1 were nonmotile, asporogenous, gram-negative slender rods with rounded ends. 16S rRNA gene sequence analysis indicated that organism should be placed in the genus Chryseobacterium. This organism contains menaquinone MK-6 as the predominent isoprenoid quinone and 3-OH iso 17:0 (40%), iso 15:0 (33%) as the major fatty acids. Phylogenetically, the nearest relative of strain W3-B1 is Chryseobacterium meningosepticum with sequence similarity of 98.4%, but DNA-DNA hybridization resulted in similarity values of only 52.3%. The G+C mol% is 34.6 mol%. Based upon results obtained by morphological, biochemical, chemotaxonomic, and molecular methods, strain W3-B1 was clearly distinguishable from other Chryseobacterium species. For these reasons, a novel species of family Flavobacteriaceae is proposed; strain W3-B1(T) (= GTC 862(T) = JCM 11413(T) = DSM 14571(T)) is the type strain.
Xiao Dong - One of the best experts on this subject based on the ideXlab platform.
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inverse weighting method for sea surface wind direction retrieval from tiangong 2 interferometric imaging radar altimeter imagery
IEEE Asia-Pacific Conference on Synthetic Aperture Radar, 2019Co-Authors: Yunhua Zhang, Xiao DongAbstract:The Interferometric Imaging Radar Altimeter (InIRA) onboard Chinese Tiangong-2 Space Laboratory is a Ku-band interferometric radar whose major aim is to measure the wide-swath ocean topography. A large number of observation data of key sea areas and typical land areas have been obtained since the start-up of InIRA. The sea surface wind field plays a major role in marine research, including weather forecasting, ocean-air interactions, and earth climate studies. Therefore, it is of great significance to use InIRA to retrieve the sea surface wind field. The local gradient method is often used for wind direction retrieval in synthetic aperture radar (SAR). However, the large change of incidence angles of InIRA imposes additional modulation on the gradient of the backscattering coefficient. In this paper, a method of combining radar backscattering coefficient inverse weighting and local gradient method is used in wind direction retrieval for InIRA. The influence of backscattering coefficient attenuation caused by angle change is analyzed and then the gradient is solved. Experimental results on Tiangong-2 data show better result is obtained using the proposed method than the local gradient method.
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sea surface wind speed retrieval and validation of the interferometric imaging radar altimeter aboard the chinese tiangong 2 Space Laboratory
IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, 2018Co-Authors: Lin Ren, Xiao Dong, Jingsong Yang, Yongjun Jia, Juan Wang, Gang ZhengAbstract:This study focuses on the retrieval and validation of sea-surface wind speeds using data from the interferometric imaging radar altimeter (InIRA) aboard the Chinese Tiangong-2 Space Laboratory. First, an empirical model, KuLMOD2, is proposed, which is a revised version of the former Ku-band low incidence model (KuLMOD) that directly relates the normalized radar cross section σ 0 to both the wind speed and incidence angle. The revised model extends the ranges of the incidence angle and wind speed and is thus applicable to the new InIRA data. The model coefficients are estimated by fitting precipitation radar data from the Tropical Rainfall Measuring Mission and collocated wind data from the European Centre for Medium-Range Weather Forecasts. The wind speeds are then retrieved from the InIRA data using KuLMOD2. For more efficient retrieval, a lookup table method is used to find the wind speed solution. Finally, the InIRA wind speeds are validated using collocated Advanced Scatterometer (ASCAT) wind speeds. The validation of the InIRA wind speed data shows that InIRA can capture regional changes and that the data have a bias of 0.02 m/s and a root-mean-square error of 1.58 m/s. This suggests that the InIRA data alone can provide valid wind speeds for future sea state bias correction of InIRA-derived sea-surface heights and that the InIRA data can act as a complement to data from other Spaceborne wind sensors.
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Interferometric Imaging Radar Altimeter on Board Chinese Tiangong-2 Space Laboratory
2018 Asia-Pacific Microwave Conference (APMC), 2018Co-Authors: Yunhua Zhang, Xiaojin Shi, Hongjian Wang, Yueyin Tan, Wenshuai Zhai, Xiao Dong, Xueyan Kang, Qingshan Yang, Dong Li, Jingshan JiangAbstract:In this paper, We introduce the Interferometric Imaging Radar Altimeter (InIRA), the first Spaceborne wide-swath ocean radar altimeter on board Chinese Tiangong-2 Space Laboratory, which was launched on September 15, 2016. The major mission of InIRA is to validate the mechanism and design of new generation ocean radar altimeter, as well as conduct preliminary application researches. The in-orbit observation results of Tiangong-2 InIRA demonstrate that it is capable of measuring the dynamic sea surface height with wide swath, sea waves of different scales and sea winds, which help us greatly improve the observation and measurement efficiency compared with traditional nadir-looking radar altimeters. Besides, it can also be used to survey and monitor the inland waters, e.g. lakes and rivers, as well as acquire terrain digital surface model (DSM). Here, we will present some typical observation results over both ocean and land surfaces.
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design and algorithms of the tiangong 2 interferometric imaging radar altimeter processor
2017 Progress In Electromagnetics Research Symposium - Spring (PIERS), 2017Co-Authors: Xiao Dong, Yunhua Zhang, Wenshuai ZhaiAbstract:The Interferometric Imaging Radar Altimeter (InIRA) operating at Ku-band (13.58 GHz) was launched on Chinese Tiangong-2 Space Laboratory on September 15, 2016. The primary goal of Tiangong-2 InIRA is to measure wide-swath sea surface height, sea waves and sea winds. Winds and waves in the observed sea area are retrieved by processing the synthetic aperture radar (SAR) images. The ocean surface topography and the digital elevation models of land areas are determined using the interferometric SAR (InSAR) technique. The scope of this paper is to present the processing algorithms for the generation of the Tiangong-2 InIRA images from the raw data. The focusing algorithm for generating the single look complex (SLC) image products and the interferometric processing algorithm for generating the surface topography are briefly introduced.
Gang Zheng - One of the best experts on this subject based on the ideXlab platform.
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sea surface wind speed retrieval and validation of the interferometric imaging radar altimeter aboard the chinese tiangong 2 Space Laboratory
IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, 2018Co-Authors: Lin Ren, Xiao Dong, Jingsong Yang, Yongjun Jia, Juan Wang, Gang ZhengAbstract:This study focuses on the retrieval and validation of sea-surface wind speeds using data from the interferometric imaging radar altimeter (InIRA) aboard the Chinese Tiangong-2 Space Laboratory. First, an empirical model, KuLMOD2, is proposed, which is a revised version of the former Ku-band low incidence model (KuLMOD) that directly relates the normalized radar cross section σ 0 to both the wind speed and incidence angle. The revised model extends the ranges of the incidence angle and wind speed and is thus applicable to the new InIRA data. The model coefficients are estimated by fitting precipitation radar data from the Tropical Rainfall Measuring Mission and collocated wind data from the European Centre for Medium-Range Weather Forecasts. The wind speeds are then retrieved from the InIRA data using KuLMOD2. For more efficient retrieval, a lookup table method is used to find the wind speed solution. Finally, the InIRA wind speeds are validated using collocated Advanced Scatterometer (ASCAT) wind speeds. The validation of the InIRA wind speed data shows that InIRA can capture regional changes and that the data have a bias of 0.02 m/s and a root-mean-square error of 1.58 m/s. This suggests that the InIRA data alone can provide valid wind speeds for future sea state bias correction of InIRA-derived sea-surface heights and that the InIRA data can act as a complement to data from other Spaceborne wind sensors.
K M Menten - One of the best experts on this subject based on the ideXlab platform.
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the quest for complex molecules in Space Laboratory spectroscopy of n butyl cyanide n c4h9cn in the millimeter wave region and its astronomical search in sagittarius b2 n
Astronomy and Astrophysics, 2012Co-Authors: Matthias H Ordu, Holger S P Muller, Adam Walters, M Nunez, Frank Lewen, A Belloche, K M MentenAbstract:Context. The saturated n -propyl cyanide was recently detected in Sagittarius B2(N). The next largest unbranched alkyl cyanide is n -butyl cyanide.Aims. We provide accurate rest frequency predictions beyond the millimeter wave range to search for this molecule in the Galactic center source Sagittarius B2(N) and facilitate its detection in Space.Methods. We investigated the Laboratory rotational spectrum of n -butyl cyanide between 75 GHz and 348 GHz. We searched for emission lines produced by the molecule in our sensitive IRAM 30 m molecular line survey of Sagittarius B2(N).Results. We identified more than one thousand rotational transitions in the Laboratory for each of the three conformers for which limited data had been obtained previously in a molecular beam microwave study. The quantum number range was greatly extended to J ≈ 120 or more and K a > 35, resulting in accurate spectroscopic parameters and accurate rest frequency calculations up to about 500 GHz for strong to moderately weak transitions of the two lower energy conformers. Upper limits to the column densities of N ≤ 3 × 1015 cm-2 and 8 × 1015 cm-2 were derived towards Sagittarius B2(N) for the two lower energy conformers, anti-anti and gauche-anti , respectively. Conclusions. Our present data will be helpful for identifying n -butyl cyanide at millimeter or longer wavelengths with radio telescope arrays such as ALMA, NOEMA, or EVLA. In particular, its detection in Sagittarius B2(N) with ALMA seems feasible.
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the quest for complex molecules in Space Laboratory spectroscopy of n butyl cyanide n c4h9cn in the millimeter wave region and its astronomical search in sagittarius b2 n
arXiv: Astrophysics of Galaxies, 2012Co-Authors: Matthias H Ordu, Holger S P Muller, Adam Walters, M Nunez, Frank Lewen, A Belloche, K M MentenAbstract:The saturated n-propyl cyanide was recently detected in Sagittarius B2(N). The next larger unbranched alkyl cyanide is n-butyl cyanide. We provide accurate rest frequency predictions beyond the millimeter wave range to search for this molecule in the Galactic center source Sagittarius B2(N) and facilitate its detection in Space. We investigated the Laboratory rotational spectrum of $n$-butyl cyanide between 75 GHz and 348 GHz. We searched for emission lines produced by the molecule in our sensitive IRAM 30 m molecular line survey of Sagittarius B2(N). We identified more than one thousand rotational transitions in the Laboratory for each of the three conformers for which limited data had been obtained previously in a molecular beam microwave study. The quantum number range was greatly extended to J ~ 120 or more and Ka > 35, resulting in accurate spectroscopic parameters and accurate rest frequency calculations up to about 500 GHz for strong to moderately weak transitions of the two lower energy conformers. Upper limits to the column densities of N <= 3 x 10E15 cm-2 and 8 x 10E15 cm-2 were derived towards Sagittarius B2(N) for the two lower energy conformers, anti-anti and gauche-anti, respectively. Our present data will be helpful for identifying n-butyl cyanide at millimeter or longer wavelengths with radio telescope arrays such as ALMA, NOEMA, or EVLA. In particular, its detection in Sagittarius B2(N) with ALMA seems feasible.
M Nunez - One of the best experts on this subject based on the ideXlab platform.
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the quest for complex molecules in Space Laboratory spectroscopy of n butyl cyanide n c4h9cn in the millimeter wave region and its astronomical search in sagittarius b2 n
Astronomy and Astrophysics, 2012Co-Authors: Matthias H Ordu, Holger S P Muller, Adam Walters, M Nunez, Frank Lewen, A Belloche, K M MentenAbstract:Context. The saturated n -propyl cyanide was recently detected in Sagittarius B2(N). The next largest unbranched alkyl cyanide is n -butyl cyanide.Aims. We provide accurate rest frequency predictions beyond the millimeter wave range to search for this molecule in the Galactic center source Sagittarius B2(N) and facilitate its detection in Space.Methods. We investigated the Laboratory rotational spectrum of n -butyl cyanide between 75 GHz and 348 GHz. We searched for emission lines produced by the molecule in our sensitive IRAM 30 m molecular line survey of Sagittarius B2(N).Results. We identified more than one thousand rotational transitions in the Laboratory for each of the three conformers for which limited data had been obtained previously in a molecular beam microwave study. The quantum number range was greatly extended to J ≈ 120 or more and K a > 35, resulting in accurate spectroscopic parameters and accurate rest frequency calculations up to about 500 GHz for strong to moderately weak transitions of the two lower energy conformers. Upper limits to the column densities of N ≤ 3 × 1015 cm-2 and 8 × 1015 cm-2 were derived towards Sagittarius B2(N) for the two lower energy conformers, anti-anti and gauche-anti , respectively. Conclusions. Our present data will be helpful for identifying n -butyl cyanide at millimeter or longer wavelengths with radio telescope arrays such as ALMA, NOEMA, or EVLA. In particular, its detection in Sagittarius B2(N) with ALMA seems feasible.
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the quest for complex molecules in Space Laboratory spectroscopy of n butyl cyanide n c4h9cn in the millimeter wave region and its astronomical search in sagittarius b2 n
arXiv: Astrophysics of Galaxies, 2012Co-Authors: Matthias H Ordu, Holger S P Muller, Adam Walters, M Nunez, Frank Lewen, A Belloche, K M MentenAbstract:The saturated n-propyl cyanide was recently detected in Sagittarius B2(N). The next larger unbranched alkyl cyanide is n-butyl cyanide. We provide accurate rest frequency predictions beyond the millimeter wave range to search for this molecule in the Galactic center source Sagittarius B2(N) and facilitate its detection in Space. We investigated the Laboratory rotational spectrum of $n$-butyl cyanide between 75 GHz and 348 GHz. We searched for emission lines produced by the molecule in our sensitive IRAM 30 m molecular line survey of Sagittarius B2(N). We identified more than one thousand rotational transitions in the Laboratory for each of the three conformers for which limited data had been obtained previously in a molecular beam microwave study. The quantum number range was greatly extended to J ~ 120 or more and Ka > 35, resulting in accurate spectroscopic parameters and accurate rest frequency calculations up to about 500 GHz for strong to moderately weak transitions of the two lower energy conformers. Upper limits to the column densities of N <= 3 x 10E15 cm-2 and 8 x 10E15 cm-2 were derived towards Sagittarius B2(N) for the two lower energy conformers, anti-anti and gauche-anti, respectively. Our present data will be helpful for identifying n-butyl cyanide at millimeter or longer wavelengths with radio telescope arrays such as ALMA, NOEMA, or EVLA. In particular, its detection in Sagittarius B2(N) with ALMA seems feasible.