Search

Your search keyword '"Kurihara J"' showing total 211 results
Start Over Author "Kurihara J"
211 results on '"Kurihara J"'

4. OI 630.0‐nm and N₂ 1PG emissions in pulsating aurora events observed by an optical spectrograph at Tromsø, Norway

Author

Tsuda, T. T. (T. T.), Li, C. (C.), Hamada, S. (S.), Hosokawa, K. (K.), Oyama, S.-i. (S.-i.), Nozawa, S. (S.), Kawabata, T. (T.), Mizuno, A. (A.), Kurihara, J. (J.), Nishiyama, T. (T.), and Kosch, M. J. (M. J.)

Subjects
Tromsø, optical spectrograph, pulsating aurora
Abstract

We performed observations of pulsating aurora (PsA) with an optical spectrograph at Tromsø, Norway, during wintertime in 2016–2017. The data analysis of multiple PsA events revealed the PsA spectra for the first time. As the results, the OI 630.0‐nm emissions and the N₂ 1PG emissions were found in the both spectra during brighter (ON) and darker (OFF) phases in the PsA events. The spectra of pulsations were derived as difference spectra between the ON and OFF spectra. From the obtained spectra of pulsations, it is found that dominant pulsations at 630.0 nm were coming from the N₂ 1PG (10,7) band, and there were less or minor contributions of the OI 630.0 nm to pulsations at 630.0 nm.

Published
2020

11. OI 630.0‐nm and N 2 1PG Emissions in Pulsating Aurora Events Observed by an Optical Spectrograph at Tromsø, Norway.

Author

Tsuda, T. T., Li, C., Hamada, S., Hosokawa, K., Oyama, S.‐i., Nozawa, S., Kawabata, T., Mizuno, A., Kurihara, J., Nishiyama, T., and Kosch, M. J.

Subjects
AURORA spectra, SPECTROGRAPHS, PHOTOMETERS, ATMOSPHERIC density, SOLAR energetic particles
Abstract

We performed observations of pulsating aurora (PsA) with an optical spectrograph at Tromsø, Norway, during wintertime in 2016–2017. The data analysis of multiple PsA events revealed the PsA spectra for the first time. As the results, the OI 630.0‐nm emissions and the N2 1PG emissions were found in the both spectra during brighter (ON) and darker (OFF) phases in the PsA events. The spectra of pulsations were derived as difference spectra between the ON and OFF spectra. From the obtained spectra of pulsations, it is found that dominant pulsations at 630.0 nm were coming from the N2 1PG (10,7) band, and there were less or minor contributions of the OI 630.0 nm to pulsations at 630.0 nm. Key Points: Pulsating aurora events were observed by an optical spectrographON and OFF spectra showed OI 630.0‐nm and N2 1PG emissionsDominant pulsations around 630.0 nm were due to N2 1PG (10,7) emissions [ABSTRACT FROM AUTHOR]

Published
2020
Full Text
View/download PDF

12. Simultaneous FPI and TMA measurements of the lower thermospheric wind in the vicinity of the poleward expanding aurora after substorm onset

Author

Oyama, S.-i. (Shin-ichiro), Kubota, K. (Ken), Morinaga, T. (Takatoshi), Tsuda, T. T. (Takuo T.), Kurihara, J. (Junichi), Larsen, M. F. (Miguel F.), Yamamoto, M. (Masayuki), and Cai, L. (Lei)

Abstract

Lower thermospheric wind fluctuations in the vicinity of an auroral arc immediately before and after a substorm onset were examined by analyzing data from a ground‐based green line Fabry‐Perot interferometer (FPI; optical wavelength of 557.7 nm) at Tromsø, Norway, and in situ measurements from a trimethyl aluminum (TMA) trail released from a sounding rocket launched during the Dynamics and Energetics of the Lower Thermosphere in Aurora 2 (DELTA‐2) campaign on 26 January 2009. Soon after the rocket launch but before disappearance of the TMA trail, a substorm onset occurred. The DELTA‐2 TMA experiment appears to be the first case in which the substorm onset occurred during the TMA wind measurement. It is known that energy dissipation induced by the ionospheric closure current is compacted at the poleward side of the discrete arc in the ionospheric morning cell. Both FPI and TMA measurements were made at the poleward side, but the FPI measured winds nearer to the poleward edge of the arc than the TMA by 110–130 km. The FPI winds at distance of 53–74 km relative to the arc edge showed clear fluctuations immediately after the substorm onset, but there was no obvious similar fluctuation in the TMA‐measured winds. The difference in the response at the two locations suggests that energy dissipation sufficient to be detected as the FPI/TMA wind perturbations was confined to the area from the poleward edge of the arc to a relative distance shorter than 163–203 km but longer than 53–74 km in this event.

Published
2017

18. Immune regulation of canine tumour and macrophage PD-L1 expression.

Author

Hartley, G., Faulhaber, E., Caldwell, A., Coy, J., Kurihara, J., Guth, A., Regan, D., and Dow, S.

Subjects
PROGRAMMED cell death 1 receptors, IMMUNE response, MACROPHAGES, NATURAL immunity, CYTOKINES
Abstract

Expression of programmed cell death receptor ligand 1 ( PD-L1) on tumor cells has been associated with immune escape in human and murine cancers, but little is known regarding the immune regulation of PD-L1 expression by tumor cells and tumor-infiltrating macrophages in dogs. Therefore, 14 canine tumor cell lines, as well as primary cultures of canine monocytes and macrophages, were evaluated for constitutive PD-L1 expression and for responsiveness to immune stimuli. We found that PD-L1 was expressed constitutively on all canine tumor cell lines evaluated, although the levels of basal expression were very variable. Significant upregulation of PD-L1 expression by all tumor cell lines was observed following IFN- γ exposure and by exposure to a TLR3 ligand. Canine monocytes and monocyte-derived macrophages did not express PD-L1 constitutively, but did significantly upregulate expression following treatment with IFN- γ. These findings suggest that most canine tumors express PD-L1 constitutively and that both innate and adaptive immune stimuli can further upregulate PD-L1 expression. Therefore the upregulation of PD-L1 expression by tumor cells and by tumor-infiltrating macrophages in response to cytokines such as IFN- γ may represent an important mechanism of tumor-mediated T-cell suppression in dogs as well as in humans. [ABSTRACT FROM AUTHOR]

Published
2017
Full Text
View/download PDF

42. Vibrational-rotational temperature measurement of N2 in the lower thermosphere by the rocket experiment

Author

Kurihara, J., Oyama, K.-I., Suzuki, K., and Iwagami, N.

Subjects
*TEMPERATURE measurements, *ATMOSPHERE, *NITROGEN, *THERMOSPHERE
Abstract

The vibrational temperature (Tv), the rotational temperature (Tr) and the number density of atmospheric molecular nitrogen (N2) were measured in situ by a sounding rocket S-310-30 inorder to study the dynamics and energetics in the lower thermosphere. Atmospheric N2 was ionized and excited using an electron gun and the emission from N2+ 1st negative (1N) bands was measured by a sensitive spectrometer. (Tv) and Tr were determined by fitting the observed spectra to synthetic spectra, and the number density was deduced from the intensities of the spectrum. The improvements of the instrument and the preliminary results of the measurement are presented. [Copyright &y& Elsevier]

Published
2003
Full Text
View/download PDF

47. OI 630.0‐nm and N21PG Emissions in Pulsating Aurora Events Observed by an Optical Spectrograph at Tromsø, Norway

Author

Tsuda, T. T., Li, C., Hamada, S., Hosokawa, K., Oyama, S.‐i., Nozawa, S., Kawabata, T., Mizuno, A., Kurihara, J., Nishiyama, T., and Kosch, M. J.

Abstract

We performed observations of pulsating aurora (PsA) with an optical spectrograph at Tromsø, Norway, during wintertime in 2016–2017. The data analysis of multiple PsA events revealed the PsA spectra for the first time. As the results, the OI 630.0‐nm emissions and the N21PG emissions were found in the both spectra during brighter (ON) and darker (OFF) phases in the PsA events. The spectra of pulsations were derived as difference spectra between the ON and OFF spectra. From the obtained spectra of pulsations, it is found that dominant pulsations at 630.0 nm were coming from the N21PG (10,7) band, and there were less or minor contributions of the OI 630.0 nm to pulsations at 630.0 nm. Pulsating aurora events were observed by an optical spectrographON and OFF spectra showed OI 630.0‐nm and N21PG emissionsDominant pulsations around 630.0 nm were due to N21PG (10,7) emissions

Published
2020
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results