RESUMEN
This paper presents the highlights of joint observations of the inner magnetosphere by the Arase spacecraft, the Van Allen Probes spacecraft, and ground-based experiments integrated into spacecraft programs. The concurrent operation of the two missions in 2017-2019 facilitated the separation of the spatial and temporal structures of dynamic phenomena occurring in the inner magnetosphere. Because the orbital inclination angle of Arase is larger than that of Van Allen Probes, Arase collected observations at higher L -shells up to L â¼ 10 . After March 2017, similar variations in plasma and waves were detected by Van Allen Probes and Arase. We describe plasma wave observations at longitudinally separated locations in space and geomagnetically-conjugate locations in space and on the ground. The results of instrument intercalibrations between the two missions are also presented. Arase continued its normal operation after the scientific operation of Van Allen Probes completed in October 2019. The combined Van Allen Probes (2012-2019) and Arase (2017-present) observations will cover a full solar cycle. This will be the first comprehensive long-term observation of the inner magnetosphere and radiation belts.
RESUMEN
The brightness of aurorae in Earth's polar region often beats with periods ranging from sub-second to a few tens of a second. Past observations showed that the beat of the aurora is composed of a superposition of two independent periodicities that co-exist hierarchically. However, the origin of such multiple time-scale beats in aurora remains poorly understood due to a lack of measurements with sufficiently high temporal resolution. By coordinating experiments using ultrafast auroral imagers deployed in the Arctic with the newly-launched magnetospheric satellite Arase, we succeeded in identifying an excellent agreement between the beats in aurorae and intensity modulations of natural electromagnetic waves in space called "chorus". In particular, sub-second scintillations of aurorae are precisely controlled by fine-scale chirping rhythms in chorus. The observation of this striking correlation demonstrates that resonant interaction between energetic electrons and chorus waves in magnetospheres orchestrates the complex behavior of aurora on Earth and other magnetized planets.
RESUMEN
Jupiter's magnetosphere is a strong particle accelerator that contains ultrarelativistic electrons in its inner part. They are thought to be accelerated by whistler-mode waves excited by anisotropic hot electrons (>10 kiloelectron volts) injected from the outer magnetosphere. However, electron transportation in the inner magnetosphere is not well understood. By analyzing the extreme ultraviolet line emission from the inner magnetosphere, we show evidence for global inward transport of flux tubes containing hot plasma. High-spectral-resolution scanning observations of the Io plasma torus in the inner magnetosphere enable us to generate radial profiles of the hot electron fraction. It gradually decreases with decreasing radial distance, despite the short collisional time scale that should thermalize them rapidly. This indicates a fast and continuous resupply of hot electrons responsible for exciting the whistler-mode waves.
RESUMEN
Trypsin [EC 3.4.21.4]-catalyzed hydrolysis of "inverse substrates" was investigated kinetically. "Inverse substrates" for trypsin are specific substrates in which the arrangement of the site-specific group is reversed compared to that of the normal substrate, e.g., a cationic center is included in the leaving group instead of being in the acyl moiety (Tanizawa, K., Kasaba, Y., & Kanaoka, Y. (1977) J. Am. Chem. Soc. 99, 4485-4488). Acyl enzyme intermediates formed specifically from these substrates are advantageous for the mechanistic analysis of trypsin action, since the cationic group liberated from the acyl moiety can no longer exhibit specific interaction with the enzyme binding site in the subsequent deacylation stage. Remarkable rate acceleration at the deacylation step was observed on adding amidinium or ammonium compounds. The effects of the size of the acyl moiety and the charged molecule on the acceleration were examined. Latent properties of 1-butylamine as an activator were found in the present study. Based on these observations, it is suggested that a cationic molecule which can be well accommodated together with the acyl group within the active center cleft causes rate enhancement, with associated conformational changes.
