| 1. |
- Ogawa, Y., et al.
(författare)
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Relationship between auroral substorm and ion upflow in the nightside polar ionosphere
- 2013
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Ingår i: J GEOPHYS RES-SPACE. - 2169-9380. ; 118:11, s. 7426-7437
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Tidskriftsartikel (refereegranskat)abstract
- We investigated ionospheric ion upflow during an auroral substorm using simultaneous European Incoherent Scatter radar and IMAGE satellite data. Approximately 6 min after an initial brightening identified with data from the IMAGE wideband imaging camera instrument, ion upflow was seen and the electron temperature became enhanced, too. The ion upflow, with a velocity of about 150 m/s, and the electron temperature enhancement lasted for about 25 min. During the poleward expansion phase, surges of large upward ion velocity and flux, and high ion and electron temperatures occurred over Longyearbyen. The upward ion flux reached 2x10(14) m(-2)s(-1). Naturally enhanced ion-acoustic lines (NEIALs) were seen near the poleward edge of the expanded auroral oval both near the end of expansion phase 17 min after onset and also later in the recovery phase. The NEIALs seemed to be accompanied by another type of enhanced echoes, obliquely to the local geomagnetic field. Data from the Low Energy Neutral Atom instrument on the IMAGE satellite show that energetic neutral oxygen reaches the IMAGE satellite about 40 min after the initial brightening, and oxygen continues to get detected during the recovery phase. We propose that ion upflow at the poleward edge of the auroral oval during the expansion phase is related to ion/neutral outflow with energy below 18-27 eV, whereas during the recovery phase of a substorm upward ions are accelerated up to about 60 eV and flow out in the entire polar region.
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| 2. |
- Maeyama, T., et al.
(författare)
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Production of a fluorescence probe in ion-beam radiolysis of aqueous coumarin-3-carboxylic acid solution-2: Effects of nuclear fragmentation and its simulation with PHITS
- 2011
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Ingår i: Radiation Physics and Chemistry. - : Elsevier BV. - 1879-0895 .- 0969-806X. ; 80:12, s. 1352-1357
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Tidskriftsartikel (refereegranskat)abstract
- The G(OH) values in aqueous coumarin-3-carboxylic-acid (3-CCA) solutions irradiated with (12)C(6+) beams having the energies of 135, 290 and 400 MeV/u were measured by a fluorescent method around the Bragg peak, with 0.6 mm intervals, and quartz cells of 1 cm optical lengths, at the Heavy Ion Medical Accelerator in Chiba, National Institute of Radiological Sciences (NIRS). For each ion, the G(OH) has been calculated as a function of dose average LET and position. The calculated results have been compared to measurements, and the results, reproducibility and reliability of the calculations are discussed in the paper.
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| 3. |
- Yoshimatsu, Yasuhiro, et al.
(författare)
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Bone morphogenetic protein-9 inhibits lymphatic vessel formation via activin receptor-like kinase 1 during development and cancer progression
- 2013
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Ingår i: Proceedings of the National Academy of Sciences. - : Proceedings of the National Academy of Sciences. - 1091-6490 .- 0027-8424. ; 110:47, s. 18940-18945
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Tidskriftsartikel (refereegranskat)abstract
- Lymphatic vessels (LVs) play critical roles in the maintenance of fluid homeostasis and in pathological conditions, including cancer metastasis. Although mutations in ALK1, a member of the transforming growth factor (TGF)-beta/bone morphogenetic protein (BMP) receptor family, have been linked to hereditary hemorrhagic telangiectasia, a human vascular disease, the roles of activin receptor-like kinase 1(ALK-1) signals in LV formation largely remain to be elucidated. We show that ALK-1 signals inhibit LV formation, and LVs were enlarged in multiple organs in Alk1-depleted mice. These inhibitory effects of ALK-1 signaling were mediated by BMP-9, which decreased the number of cultured lymphatic endothelial cells. Bmp9-deficient mouse embryos consistently exhibited enlarged dermal LVs. BMP-9 also inhibited LV formation during inflammation and tumorigenesis. BMP-9 downregulated the expression of the transcription factor prospero-related homeobox 1, which is necessary to maintain lymphatic endothelial cell identity. Furthermore, silencing prospero-related homeobox 1 expression inhibited lymphatic endothelial cell proliferation. Our findings reveal a unique molecular basis for the physiological and pathological roles of BMP-9/ALK-1 signals in LV formation.
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