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We have developed a low-energy particle experiment that alternately measures ions and electrons in space. The ability to switch between ion and electron measurements is achieved by simply adding ultra-thin carbon foils and positive and negative outputs to a conventional top-hat electrostatic analyzer and a high-voltage power supply, respectively. The advantage of this experiment is that it can perform both ion and electron measurements using only one MCP-based detector for electrons, since it detects secondary electrons emitted from the carbon foils. For the SS520-3 sounding rocket program, we prepared two identical energy analyzers, one for ions and the other for electrons to demonstrate this technique. Laboratory tests confirmed that the performance of the two analyzers was comparable to that of conventional analyzers for ion and electrons. The SS520-3 rocket experiment in the high latitude auroral region yielded observations that captured typical features of ions and electrons, which were similar to previous observations. [ABSTRACT FROM AUTHOR]

We have developed a low-energy particle experiment that alternately measures ions and electrons in space. The ability to switch between ion and electron measurements is achieved by simply adding ultra-thin carbon foils and positive and negative outputs to a conventional top-hat electrostatic analyzer and a high-voltage power supply, respectively. The advantage of this experiment is that it can perform both ion and electron measurements using only one MCP-based detector for electrons, since it detects secondary electrons emitted from the carbon foils. For the SS520-3 sounding rocket program, we prepared two identical energy analyzers, one for ions and the other for electrons to demonstrate this technique. Laboratory tests confirmed that the performance of the two analyzers was comparable to that of conventional analyzers for ion and electrons. The SS520-3 rocket experiment in the high latitude auroral region yielded observations that captured typical features of ions and electrons, which were similar to previous observations. [ABSTRACT FROM AUTHOR]

BepiColombo Mio (previously called MMO: Mercury Magnetospheric Orbiter) was successfully launched by Ariane 5 from Kourou, French Guiana on October 20, 2018. The Mercury Plasma/Particle Experiment (MPPE) is a comprehensive instrument package onboard Mio spacecraft used for plasma, high-energy particle and energetic neutral atom measurements. It consists of seven sensors including two Mercury Electron Analyzers (MEA1 and MEA2), Mercury Ion Analyzer (MIA), Mass Spectrum Analyzer (MSA), High Energy Particle instrument for electron (HEP-ele), High Energy Particle instrument for ion (HEP-ion), and Energetic Neutrals Analyzer (ENA). Significant efforts were made pre-flight to calibrate all of the MPPE sensors at the appropriate facilities on the ground. High voltage commissioning of MPPE analyzers was successfully performed between June and August 2019 and in February 2020 following the completion of the low voltage commissioning in November 2018. Although all of the MPPE analyzers are now ready to begin observation, the full service performance has been delayed until Mio's arrival at Mercury. Most of the fields of view (FOVs) of the MPPE analyzers are blocked by the thermal shield surrounding the Mio spacecraft during the cruising phase. Together with other instruments on Mio including Magnetic Field Investigation (MGF) and Plasma Wave Investigation (PWI) that measure plasma field parameters, MPPE will contribute to the comprehensive understanding of the plasma environment around Mercury when BepiColombo/Mio begins observation after arriving at the planet Mercury in December 2025. [ABSTRACT FROM AUTHOR]

We suggest that the next era of Heliophysics should focus on the Sun–Heliosphere and Geospace as each a system-of-systems, and recommend a coordinated, deliberate, worldwide scientific effort to answer long-standing questions that will remain unanswered without a unified program. Many of the biggest unanswered science questions that remain across Heliophysics center around the interconnectivity of the different physical systems and the role of mesoscale dynamics in modulating, regulating, and controlling that interconnected behavior. Heliophysics has made key progress understanding both the large-scale dynamics and the microphysical processes that occur in these dynamic systems. Such understanding grew out of a systematic approach to study both limits of the system, from global, with the coordinated missions of the International Solar Terrestrial Physics (ISTP) program, to micro, with largely uncoordinated (albeit coincident) missions such as Cluster, Time History of Events and Macroscale Interactions during Substorms (THEMIS), Van Allen Probes, Magnetospheric Multiscale (MMS), Parker Solar Probe, and Solar Orbiter. We suggest that the international Heliophysics community should embark on a grand program to study these system-of-systems holistically, with coordinated, multipoint measurements. We particularly recommend an emphasis on resolving the mesoscale dynamics that links micro to global, and a whole-of-science approach that includes ground-based measurements and advanced numerical modeling. In effect, we propose a mesoscale ISTP type program that would consist of a system of Great Observatories capable of revealing the connections among systems from the solar interior to the top of Earth's atmosphere. The paradigm and specific approaches outlined in this paper could serve as a strategic imperative and overarching theme that binds our Solar and Space Physics communities together under a common scientific objective. By its very nature, the type of program we argue for would be large, with several coordinated elements, and international in scope. It would include space-borne missions and coordinated ground-based observatories, artificial intelligence/machine learning (AI/ML) methods of analyzing large and complex datasets, and next-generation numerical modeling. The need to coordinate and integrate these different elements is independent of any specific mission implementation. Hence, we suggest the Heliophysics community organize around an ISTP-type program, ISTPNext, with associated Heliophysics "Great Observatories". [ABSTRACT FROM AUTHOR]

Plasma signature around crustal magnetic fields is one of the most important topics of the lunar plasma sciences. Although recent spacecraft measurements are revealing solar–wind interaction with the lunar crustal fields on the dayside, plasma signatures around crustal fields on the night side have not been fully studied yet. Here we show evidence of plasma trapping on the closed field lines of the lunar crustal fields in the solar–wind wake, using SELENE (Kaguya) plasma and magnetic field data obtained at 14–15 km altitude from the lunar surface. In contrast to expectation on plasma cavity formation at the strong crustal fields, electron flux is enhanced above Crisium Antipode (CA) anomaly which is one of the strongest lunar crustal fields. The enhanced electron fluxes above CA are characterised by (1) occasional bi-directional field-aligned beams in the lower energy range (<150 eV) and (2) a medium energy component (150–300 eV) that has a double loss-cone distribution representing bounce motion between the two footprints of the crustal magnetic fields. The low-energy electrons on the closed field lines may come from the lunar night side surface, while supply mechanism of medium-energy electrons on the closed field line remains to be solved. We also report that a density cavity in the wake is observed not above the strongest magnetic field but in its vicinity. [ABSTRACT FROM AUTHOR]

Abstract: We investigate Kaguya observation of ion acceleration around a lunar crustal magnetic anomaly located in the South Pole-Aitken basin at an altitude of 100km. The accelerated ions in the 230eV to 1.5keV energy range were identified by a characteristic dispersion signature in the energy-time spectrogram that appeared repeatedly upon Kaguya׳s approach to the magnetic anomaly. The interplanetary magnetic field was almost parallel to the solar wind velocity and thus the electric field was very small. The results of our analysis show that ions with energies below 230eV were accelerated up to 1.5keV by an electric field produced by the interaction between the solar wind and the magnetic anomaly. We argue that the low-energy ions mainly originated from the solar wind ions with energies of 450eV that were backscattered on the lunar surface. [Copyright &y& Elsevier]

Aim Proton beam therapy is safe and more effective than conventional radiation therapy for the local control of nodular hepatocellular carcinoma ( HCC). However, evaluating therapeutic response by imaging is not accurate during the early post-irradiation period. Therefore, we examined whether the histopathological study of biopsy specimens obtained at 3 weeks after irradiation can be used to more accurately assess therapeutic response. Methods Fifteen HCC lesions from 13 patients were treated with proton beam irradiation. Tissue biopsy samples were obtained using abdominal ultrasound-guided percutaneous fine-needle aspiration from the center of the tumor before, 3 weeks after and 1 year post-proton therapy. The specimens were examined after staining with hematoxylin-eosin ( HE) and a MIB-1 antibody. Results MIB-1 labeling indices ( LI) before treatment were 13.0 ± 8.5% (mean ± SD; range, 0.6-27.0), whereas those 3 weeks after proton therapy were significantly reduced to 3.2 ± 2.4% (range, 0.6-8.9) ( P < 0.05). Although the tumor size was reduced, we did not observe a reduction in tumor blood flow by dynamic computed tomography or degenerative changes by HE. All lesions that displayed reduced MIB-1 LI at 3 weeks post-proton treatment were ultimately diagnosed as complete response at 1 year after treatment. In contrast, one case with increased MIB-1 LI at 3 weeks had significant tumor size progression at 1 year post-treatment. Conclusion The percutaneous fine-needle aspiration biopsy of HCC is a safe and useful tool that can be used to evaluate the response to proton irradiation. In particular, MIB-1 LI may provide additional information to assess the therapeutic response of HCC during the early post-irradiated period. [ABSTRACT FROM AUTHOR]

Short-period magnetic enhancements were detected by the MAP-LMAG magnetometer onboard Kaguya orbiting the moon in the solar wind at an altitude of 100 km. The duration was typically 10 s, which corresponds to 0.5 degrees in latitude along the Kaguya orbit and a scale size of 15 km. The magnitude of the magnetic field was enhanced up to 1.5–3.6 times as large as that of the preceding quiet periods. No such magnetic enhancements were found in the upstream solar wind magnetic field. The short-period magnetic enhancements were categorized into 2 groups. One is the sub-ion-gyro-scale limb compression detected at the terminator region of the moon in a nearly constant solar wind magnetic field. The magnetic field flared away from the moon consistently with the previously known limb compressions. The scale size deduced from the duration was 11 km, 85 times as small as that of previously reported limb compressions. It is significantly smaller than the typical proton gyroradius 50–100 km in the solar wind at 1AU. The other types of magnetic enhancements appeared at crossings of magnetic discontinuities of the solar wind. Some of them were found on the nightside of the moon. A possible explanation is that they were magnetic fields compressed by the solar wind ions reflected at the moon channeled back along the current sheet of an interplanetary tangential discontinuity, similar to the hot flow anomalies observed at the Earth's bow shock. The reflected ions themselves were not detected on the nightside of the moon, while the magnetic field compressed by the expanding region can penetrate through the moon to be detected as magnetic field enhancements on the nightside of the moon. [ABSTRACT FROM AUTHOR]

MAP-PACE (MAgnetic field and Plasma experiment-Plasma energy Angle and Composition Experiment) on SELENE (Kaguya) has completed its ∼1.5-year observation of low-energy charged particles around the Moon. MAP-PACE consists of 4 sensors: ESA (Electron Spectrum Analyzer)-S1, ESA-S2, IMA (Ion Mass Analyzer), and IEA (Ion Energy Analyzer). ESA-S1 and S2 measured the distribution function of low-energy electrons in the energy range 6 eV-9 keV and 9 eV-16 keV, respectively. IMA and IEA measured the distribution function of low-energy ions in the energy ranges 7 eV/q-28 keV/q and 7 eV/q-29 keV/q. All the sensors performed quite well as expected from the laboratory experiment carried out before launch. Since each sensor has a hemispherical field of view, two electron sensors and two ion sensors installed on the spacecraft panels opposite each other could cover the full 3-dimensional phase space of low-energy electrons and ions. One of the ion sensors IMA is an energy mass spectrometer. IMA measured mass-specific ion energy spectra that have never before been obtained at a 100 km altitude polar orbit around the Moon. The newly observed data show characteristic ion populations around the Moon. Besides the solar wind, MAP-PACE-IMA found four clearly distinguishable ion populations on the dayside of the Moon: (1) Solar wind protons backscattered at the lunar surface, (2) Solar wind protons reflected by magnetic anomalies on the lunar surface, (3) Reflected/backscattered protons picked-up by the solar wind, and (4) Ions originating from the lunar surface/lunar exosphere. [ABSTRACT FROM AUTHOR]

We have developed circular one-dimensional position-sensitive time-of-flight microchannel plate (MCP) detector for space plasma measurements. The MCP detector is equipped with a 354.375° resistive anode and a grid anode for obtaining position and timing signals simultaneously from one start event. The resistive anode provides high-resolution and continuous position sensing with two electronic channels alone. The grid anode generates start signals with pulse width of 1 ns for time-of-flight measurements. The resistive anode is formed on an alumina substrate which is installed behind the output side of the MCP plates. The grid anode is installed between the MCP plates and the resistive anode for the simultaneous detection of position and start signals. Stop signals are obtained from stop events by a center anode formed on the alumina substrate behind the MCP plates. On the basis of the test experiments, we have evaluated that the MCP detector functionally deals with the position and timing signals. [ABSTRACT FROM AUTHOR]

We have developed an ion energy mass spectrometer for use aboard three-axis stabilized spacecraft. This spectrometer measures the three-dimensional distribution function of mass-discriminated ions with a high sampling rate using electrostatic energy analysis and time-of-flight mass analysis. Three-axis stabilized spacecraft make it difficult to obtain complete coverage of all possible plasma arrival directions. We have added angular scanning deflectors to a cylindrically symmetric analyzer to provide a hemispherical (2π str) field of view. Ion analyzers need suitable sensitivity with respect to surrounding space plasma fluxes, whose intensities vary greatly depending especially on plasma regions such as the solar wind and the planetary magnetospheres. To obtain a wide range of sensitivity, we equipped the analyzer with sensitivity control electrodes. Ions originating from planetary atmosphere and surface include various ion species such as Na+, Mg+, Al+, and Fe+. The time-of-flight device of our spectrometer applies a peculiar electric field, called a linear electric field, which increases linearly with the penetration length of incident ions to enable mass resolution higher than that of conventional time-of-flight techniques. In this electric field, ions bounce in simple harmonic motion, where the energy and flight path no longer affect the flight time and thus the mass resolution. We have designed and fabricated the ion energy mass spectrometer, and have evaluated its performance through laboratory experiments. [ABSTRACT FROM AUTHOR]

The density of the solar wind plasma near the Earth's magnetosphere sometimes decreases to only several per cent of the usual value, and such density extrema result in a significant reduction of the dynamic pressure and Alfvén Mach number ( M A ) of the solar wind flow. While a symmetric expansion of the Earth's magnetosphere by the low dynamic pressure was assumed in previous studies, a global magnetohydrodynamic (MHD) simulation study predicted a remarkable dawn-dusk asymmetry of the magnetospheric shape under low-density solar wind and Parker-spiral interplanetary magnetic field (IMF) configuration. Here, we present observations consistent with the asymmetric deformation of the magnetosphere under low- M A solar wind and Parker-spiral IMF conditions, focusing on the significant expansion of the dawn-flank magnetosphere detected by the Geotail spacecraft. A global MHD simulation reproduced the dawnward expansion of the near-Earth magnetosphere, which was consistent with the observation by Geotail. The solar wind flow had a non-negligible dusk-to-dawn component and partly affected the dawnward expansion of the magnetosphere. Local, roughly Alfvénic sunward acceleration of magnetosheath ions at the dawn flank magnetopause suggests magnetosheath plasma entry into the magnetosphere through open field lines generated by magnetic reconnection at the dayside magnetopause. At the same time, Cluster 1 and 3, located near the southern polar cusp, also detected continuous antisunward ion jets and occasional sunward jets, which are consistent with the occurrence of magnetic reconnection near the southern cusp. These observations suggest that enhanced plasma acceleration at the dayside magnetopause operates under the low- M A solar wind and Parker spiral IMF conditions and that plasma influx across the dawnside magnetopause is at work under such a low- M A condition. These results can be helpful in understanding interactions between low- M A solar/stellar winds and celestial objects, such as inner planets and exoplanets. [ABSTRACT FROM AUTHOR]

Understanding Mercury's magnetosphere is crucial for advancing our comprehension of how the solar wind interacts with the planetary magnetospheres. Despite previous missions, several gaps remain in our knowledge of Mercury's plasma environment. Here, we present findings from BepiColombo's third flyby, offering a synoptic view of the large scale structure and composition of Mercury's magnetosphere. The Mass Spectrum Analyzer (MSA), Mass Ion Analyzer (MIA), and Mass Electron Analyzer (MEA) on the magnetospheric orbiter reveal insights, including the identification of trapped energetic hydrogen (H+) with energies around 20 keV e−1 evidencing a ring current, and a cold ion plasma with energies below 50 eV e−1. Additionally, we observe a Low-Latitude Boundary Layer (LLBL), which is a region of turbulent plasma at the edge of the magnetosphere, characterized by bursty ion enhancements, indicating an ongoing injection process in the duskside magnetosphere flank. These observations during cruise phase provide a tantalizing glimpse of future discoveries expected from the Mercury Plasma Particle Experiment (MPPE) instruments after orbit insertion, promising broader impacts on our understanding of planetary magnetospheres. Due to its proximity to the Sun, the space plasma environment of Mercury is tightly coupled with the interior and the surface of the planet, and their interaction facilitate the escape of planetary material and energy exchange. The authors present data from the third flyby of the BepiColombo spacecraft revealing new evidence of trapped energetic hydrogen (H+) with energies of around 20 keV/e and highlight the presence of cold ion population below 50 eV/e in Mercury's magnetosphere. [ABSTRACT FROM AUTHOR]

The aim of this study was to clarify whether histological parameters reflected tumor aggressiveness in patients with hepatocellular carcinoma (HCC). The tumor volume doubling times (TVDTs) of 21 HCCs, less than 3 cm in diameter at the start of the observation period, were calculated in 21 patients in whom the natural progression of the lesion was observed by ultrasonography. Paraffin-embedded sections were prepared from samples obtained by ultrasound-guided fine-needle liver biopsy at the end of the observation period. The histological parameters examined were the MIB-1 labeling index (LI), for which we performed immunohistochemical staining with the MIB-1 monoclonal antibody, using an antigen retrieval method; the nucleo-cytoplasmic (N/C ratio), cellularity, and the nuclear form factor (NFF), were calculated with an imaging analyzer. We performed multiple regression analysis for estimating the growth of small HCCs. With the N/C ratio (0.154 +/- 0.068; mean +/- SD), cellularity (453 +/- 21.8 cells/10(4) microm2), NFF (1.150 +/- 0.096), and degree of HCC differentiation as independent variables, only the MIB-1 LI (11.8 +/- 6.1%) showed a significant correlation with TVDT (207.5 +/- 162.6 days) (r = -0.658; P < 0.05). Compared to the conventional indices of histological atypism tested, i.e., N/C ratio, cellularity NFF, and degree of HCC differentiation, only MIB-1 LI was significantly correlated with small HCC growth rate. The MIB-1 LI may therefore be a simple and useful index of tumor aggressiveness. [ABSTRACT FROM AUTHOR]

We present initial results of low‐energy ion observations from BepiColombo's first Mercury flyby. Unprecedentedly high time resolution measurements of low energy ions at Mercury by BepiColombo Mio reveal rapid (a few seconds) and large (1–2 orders of magnitude) fluctuations of ion flux around the magnetopause and within the magnetosphere. Around the magnetic equator in the pre‐midnight magnetotail, Mio observed plasma sheet ions consistent with previous observations. In the midnight magnetotail near the closest approach, Mio observed the co‐existence of high‐energy (∼keV/q) and low‐energy (<∼300 eV/q) ion components. The low‐energy component is inferred to be cold with a temperature well below 100 eV and have a major contribution to the total density as opposed to previously reported cold tenuous ions. Future observations by Mio will provide insights into the sources, transport, and acceleration of the newly identified ion components. Plain Language Summary: BepiColombo, launched on 20 October 2018, is now en route to Mercury. Along its 7‐year journey to the Mercury orbit insertion, BepiColombo conducted, and will conduct, nine planetary flybys in total. This paper presents brand‐new observations of ions (positively charged particles) in Mercury's magnetosphere by BepiColombo Mio during its first encounter with Mercury. Thanks to high‐time resolution measurements by Mio, it is revealed that ions around Mercury change dramatically and rapidly just over a few seconds. Mio also observed an unexpectedly dense ion population with low energies, for which we do not have a definitive explanation yet. Future flyby and in‐orbit observations by BepiColombo will provide key information for unraveling the dynamics and sources of ions in Mercury's magnetosphere. Key Points: We present initial reports on low energy ion observations during BepiColombo's first Mercury flybyMio observed large fluctuations of ion flux with time scales down to a few seconds around the magnetopause and within the magnetosphereIon energy spectra obtained in the midnight magnetotail suggest the presence of an unexpectedly dense cold component [ABSTRACT FROM AUTHOR]

The Moon interacts with the incident solar wind plasma in various ways, and most of these interactions are accompanied by variations of the interplanetary magnetic field (IMF) around the Moon. Here we first report decreases of the IMF strength observed at 100 km altitude on the lunar dayside and over the polar region, comparing upstream solar wind data from ACE with Kaguya (SELENE) data. We note that the magnetic field decreases are observed above non-magnetized regions or very weakly magnetized regions. In one event the IMF is weakened in the dayside northern hemisphere when the IMF is roughly anti-parallel to the solar wind flow. We estimate that the decrease in the magnetic pressure can be partly compensated by the thermal pressure of the back-scattered solar wind protons, which suggests that the magnetic field decrease is interpreted as diamagnetic effect by the back-scattered protons. In another event an IMF decrease is continuously detected from the northern polar region to the dayside mid-latitude region, which is not fully explained by the thermal pressure of the back-scattered protons. We also discuss the diamagnetic current system in the upstream (fore-moon) solar wind region formed by the back-scattered protons. • Kaguya detected decreases of solar wind magnetic field on the lunar dayside. • Thermal pressure of back-scattered solar wind protons is considered. • The phenomenon represents diamagnetic effect by the back-scattered protons. • Magnetic field decrease over the North Pole remains to be studied. • Diamagnetic current system on the lunar dayside is presented. [ABSTRACT FROM AUTHOR]

This study investigates the escape of Mercury's sodium‐group ions (Na+‐group, including ions with m/q from 21 to 30 amu/e) and their dependence on true anomaly angle (TAA), that is, Mercury's orbital phase around the Sun, using measurements from MESSENGER. The measurements are categorized into solar wind, magnetosheath, and magnetosphere, and further divided into four TAA intervals. Na+‐group ions form escape plumes in the solar wind and magnetosheath, with higher fluxes along the solar wind's motional electric field. The total escape rates vary from 0.2 to 1 × 1025 atoms/s with the magnetosheath being the main escaping region. These rates exhibit a TAA dependence, peaking near the perihelion and similar during Mercury's remaining orbit. Despite Mercury's tenuous exosphere, Na+‐group ions escape rate is comparable to other inner planets. This can be attributed to several processes, including that Na+‐group ions may include several ion species, efficient photoionization frequency for elements within Na‐group, etc. Plain Language Summary: Atmospheric escape is defined as the loss of atmospheric particles in the form of neutrals and ions into outer space. Understanding atmospheric escape is a fundamental science question for studying the evolution of planetary atmosphere and habitability, as it can provide insight into how life can form on a planet. While atmospheric escape has been extensively studied in Venus, Earth, and Mars through in situ measurements and simulations, it remains poorly understood at Mercury. In this study, we investigate the escape of the most abundant heavy ions at Mercury, specifically the Na+‐group ions, using MESSENGER's measurements. Our findings show that the escape rates of the Na+‐group ions are dependent on Mercury's orbital phase around the Sun, exhibiting a seasonal effect with rates from 0.2 to 1 × 1025 atoms/s. This rate is comparable to the ion's escape rates at other inner planets, which is surprising given that Mercury only has a tenuous exosphere. We propose that this can be attributed to several processes such as efficient photoionization, solar wind sputtering, and solar wind momentum exchange at Mercury, and the Na+‐group ions include several ion species such as Na+, aluminum ion (Al+), silicon ion (Si+) and magnesium ion (Mg+) etc. Key Points: Na+‐group ions form escape plumes in solar wind and magnetosheath, with higher fluxes in the positive solar wind electric field hemisphereThe escape rate ranges from 0.2 to 1 × 1025 atoms/s, with the magnetosheath being the main escaping regionEscape rates peak near perihelion, and are similar during other true anomaly angle (TAA) intervals [ABSTRACT FROM AUTHOR]

Interaction between the Moon and solar wind plasma is the important issues of the planetary plasma sciences. The Moon is an obstacle large enough to interact with the incident solar wind plasma, and most of these interactions are accompanied by variations of the interplanetary magnetic field (IMF) around the Moon. A decrease of the IMF takes place around the wake boundary due to the diamagnetic effect, while no IMF decrease on the lunar dayside has been reported so far. Here we report decreases of the IMF strength observed at 100 km altitude on the lunar dayside and over the polar region, comparing upstream solar wind data from ACE with Kaguya data. We note that the magnetic field decreases are observed above non-magnetized regions or very weakly magnetized regions. In one event the IMF is weakened in the dayside northern hemisphere when the IMF is roughly anti-parallel to the solar wind flow. We estimate that the decrease in the magnetic pressure can be partly compensated by the thermal pressure of the back-scattered solar wind protons, which suggests that the magnetic field decrease is interpreted as diamagnetic effect by the back-scattered protons. In another event an IMF decrease is continuously detected from the northern polar region to the dayside mid-latitude region, which is not fully explained by the thermal pressure of the back-scattered protons. The Kaguya LRS/WFC data show a slight increase in the electron density around the northern pole, which suggests an increase in the positive ion density. The density increase might be attributed to the back-/forward-scattered solar wind protons as well as heavy ions originating from the lunar surface and/or exosphere, while the heavy ions may not contribute to an increase in the thermal pressure because their temperature is very low. We also discuss the diamagnetic current system in the upstream (fore-moon) solar wind. [ABSTRACT FROM AUTHOR]

Among nearly 300 near‐Mercury tail current sheet crossings performed by the MESSENGER spacecraft, we identified 37 traversals of an asymmetric current sheet, wherein the lobe densities on opposite sides differ by a factor of three or more. These asymmetric current sheet crossings primarily occur on the dawnside. A global magnetohydrodynamic (MHD) simulation was found to be in excellent agreement with the observations. The results suggest that the north–south density asymmetry is caused by solar wind entering via an upstream‐connected window in one hemisphere. Furthermore, the Parker spiral interplanetary magnetic field (IMF) controls the near‐tail density asymmetries, whereas Mercury's offset dipole magnetic field controls those in mid‐ or distant‐tail regions. We propose that hemispheric asymmetries in Mercury's magnetospheric convection occur under strong IMF conditions. Plain Language Summary: Mercury possesses a small magnetosphere owing to its weak planetary magnetic field and strong interactions with the solar wind in the inner heliosphere. The transport process of the solar wind mass and energy into its magnetosphere remains unclear. Previous MESSENGER observations suggest that although the Earth‐like plasma mantle is detected inside the near‐tail magnetopause in normal IMF magnitudes, it is not a permanent feature of Mercury's magnetosphere. Here we report, for the first time, that solar wind ions can enter deep into the near‐tail region via an upstream‐connected window in one hemisphere and form a density‐asymmetric current sheet under strong IMF conditions. Through MHD simulations, we revealed tail dawn–dusk asymmetries during the transport of solar wind plasma. Advanced data expected from BepiColombo will further improve our understanding of the solar wind–magnetosphere coupling. Key Points: North–south asymmetries exist in Mercury's magnetotailBoth the interplanetary magnetic field (IMF) BX polarity and intrinsic offset dipole magnetic field control the north–south density asymmetry in Mercury's tailThe IMF Parker spiral results in a dawnside preference for the plasma asymmetric current sheet [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article on the clinical features of small intestinal mucosal injury in users of chronic non-steroidal anti-inflammatory drug (NSAID) in Japan.

There forms a tenuous region called the wake behind the Moon in the solar wind, and plasma entry/refilling into the wake is a fundamental problem of the lunar plasma science. High-energy ions and electrons in the foreshock of the Earth’s magnetosphere were detected at the lunar surface in the Apollo era, but their effects on the lunar night-side environment have never been studied. Here we show the first observation of bow-shock reflected protons by Kaguya (SELENE) spacecraft in orbit around the Moon, confirming that solar wind plasma reflected at the terrestrial bow shock can easily access the deepest lunar wake when the Moon stays in the foreshock (We name this mechanism ‘type-3 entry’). In a continuous type-3 event, low-energy electron beams from the lunar night-side surface are not obvious even though the spacecraft location is magnetically connected to the lunar surface. On the other hand, in an intermittent type-3 entry event, the kinetic energy of upward-going field-aligned electron beams decreases from ∼ 80 eV to ∼ 20 eV or electron beams disappear as the bow-shock reflected ions come accompanied by enhanced downward electrons. According to theoretical treatment based on electric current balance at the lunar surface including secondary electron emission by incident electron and ion impact, we deduce that incident ions would be accompanied by a few to several times higher flux of an incident electron flux, which well fits observed downward fluxes. We conclude that impact by the bow-shock reflected ions and electrons raises the electrostatic potential of the lunar night-side surface. [ABSTRACT FROM AUTHOR]

A scaffold-hopping strategy towards a new pyrazolo[1,5- a ]pyridine based core using molecular hybridization of two structurally distinct EP 1 antagonists, followed by structure-activity relationship-guided optimization, resulted in the identification of potent EP 1 antagonists exemplified by 4c , 4f , and 4j , which were shown to reduce pathological intravesical pressure in rats when administered at 1 mg/kg iv. [ABSTRACT FROM AUTHOR]

HNF4α regulates various genes to maintain liver function. There have been reports linking HNF4α expression to the development of non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis. In this study, liver-specific Hnf4a -deficient mice (Hnf4a ΔHep mice) developed hepatosteatosis and liver fibrosis, and they were found to have difficulty utilizing glucose. In Hnf4a ΔHep mice, the expression of fatty acid oxidation-related genes, which are PPARα target genes, was increased in contrast to the decreased expression of PPARα, suggesting that Hnf4a ΔHep mice take up more lipids in the liver instead of glucose. Furthermore, Hnf4a ΔHep/ Ppara −/− mice, which are simultaneously deficient in HNF4α and PPARα, showed improved hepatosteatosis and fibrosis. Increased C18:1 and C18:1/C18:0 ratio was observed in the livers of Hnf4a ΔHep mice, and the transactivation of PPARα target gene was induced by C18:1. When the C18:1/C18:0 ratio was close to that of Hnf4a ΔHep mouse liver, a significant increase in transactivation was observed. In addition, the expression of Pgc1a , a coactivator of PPARs, was increased, suggesting that elevated C18:1 and Pgc1a expression could contribute to PPARα activation in Hnf4a ΔHep mice. These insights may contribute to the development of new diagnostic and therapeutic approaches for NAFLD by focusing on the HNF4α and PPARα signaling cascade. [ABSTRACT FROM AUTHOR]

Remotely sensed interplanetary scintillation (IPS) data from the Institute for Space-Earth Environmental Research (ISEE), Japan, allows a determination of solar-wind parameters throughout the inner heliosphere. We show the 3D analysis technique developed for these data sets that forecast plasma velocity, density, and component magnetic fields at Earth, as well at the other inner heliospheric planets and spacecraft. One excellent coronal mass ejection (CME) example that occurred on the 10 March 2022 was viewed not only in the ISEE IPS analyses, but also by the spacecraft near Earth that measured the CME arrival at one AU. Solar Orbiter, that was nearly aligned along the Earth radial at 0.45 AU, also measured the CME in plasma density, velocity, and magnetic field. BepiColombo at 0.42 AU was also aligned with the STEREO A spacecraft, and viewed this CME. The instruments used here from BepiColombo include: 1) the European-Space-Agency Mercury-Planetary-Orbiter magnetic field measurements; 2) the Japan Aerospace Exploration Agency Mio spacecraft Solar Particle Monitor that viewed the CME Forbush decrease, and the Mercury Plasma Experiment/Mercury Electron Analyzer instruments that measured particles and solar-wind density from below the spacecraft protective sunshield covering. This article summarizes the analysis using ISEE, Japan real-time data for these forecasts: it provides a synopsis of the results and confirmation of the CME event morphology after its arrival, and discusses how future IPS analyses can augment these results. [ABSTRACT FROM AUTHOR]

The fundamental processes responsible for energy exchange between large-scale electromagnetic fields and plasma are well understood theoretically, but in practice these theories have not been tested. These processes are ubiquitous in all plasmas, especially at the interface between high and low beta plasmas in planetary magnetospheres and other magnetic environments. Although such boundaries pervade the plasma Universe, the processes responsible for the release of the stored magnetic and thermal plasma energy have not been fully identified and the importance of the relative impact of each process is unknown. Despite advances in understanding energy release through the conversion of magnetic to kinetic energy in magnetic reconnection, how the extreme pressures in the regions between stretched and more relaxed field lines in the transition region are balanced and released through adiabatic convection of plasma and fields is still a mystery. Recent theoretical advances and the predictions of large-scale instabilities must be tested. In essence, the processes responsible remain poorly understood and the problem unresolved. The aim of the White Paper submitted to ESA's Voyage 2050 call, and the contents of this paper, is to highlight three outstanding open science questions that are of clear international interest: (i) the interplay of local and global plasma physics processes: (ii) the partitioning during energy conversion between electromagnetic and plasma energy: and (iii) what processes drive the coupling between low and high beta plasmas. We present a discussion of the new measurements and technological advances required from current state-of-the-art, and several candidate mission profiles with which these international high-priority science goals could be significantly advanced. [ABSTRACT FROM AUTHOR]

This study analyzes the flux transfer event (FTE)-type flux ropes and magnetic reconnection around the dayside magnetopause during BepiColombo's Earth flyby. The magnetosheath has a high plasma β (∼ 8), and the interplanetary magnetic field (IMF) has a significant radial component. Six flux ropes are identified around the magnetopause. The motion of flux ropes together with the maximum magnetic shear model suggests that the reconnection X-line possibly swipes BepiColombo near the magnetic equator due to an increase in the radial component of the IMF. The flux rope with the highest flux content contains a clear coalescence signature, i.e., two smaller flux ropes merge, supporting theoretical predictions that the flux contents of flux ropes can grow through coalescence. The coalescence of the two FTE-type flux ropes takes place through secondary reconnection at the point of contact between the two flux ropes. The BepiColombo measurements indicate a large normalized guide field and a reconnection rate comparable to that measured at the magnetopause (∼ 0.1). [ABSTRACT FROM AUTHOR]

The Jupiter Icy Moons Explorer (JUICE) is a science mission led by the European Space Agency, being developed for launch in 2023. The Ganymede Laser Altimeter (GALA) is an instrument onboard JUICE, whose main scientific goals are to understand ice tectonics based on topographic data, the subsurface structure by measuring tidal response, and small-scale roughness and albedo of the surface. In addition, from the perspective of astrobiology, it is imperative to study the subsurface ocean scientifically. The development of GALA has proceeded through an international collaboration between Germany (the lead), Japan, Switzerland, and Spain. Within this framework, the Japanese team (GALA-J) is responsible for developing three receiver modules: the Backend Optics (BEO), the Focal Plane Assembly (FPA), and the Analog Electronics Module (AEM). Like the German team, GALA-J also developed software to simulate the performance of the entire GALA system (performance model). In July 2020, the Proto-Flight Models of BEO, FPA, and AEM were delivered from Japan to Germany. This paper presents an overview of JUICE/GALA and its scientific objectives and describes the instrumentation, mainly focusing on Japan's contribution. [ABSTRACT FROM AUTHOR]

Abstract: Our recent observations around the Moon revealed that so-called type-II (T2) entry of the solar wind protons into the near-Moon wake occurs when the IMF is dominated by the non-radial components (i.e. B Y and/or B Z ). Under this condition a part of the solar wind protons scattered/reflected at the lunar dayside surface subsequently enters the central region of the near-Moon wake after a large-scale cycloid motion, which accelerates electrons along the filed line into the wake. The situation handled in the previous studies is that the relevant magnetic field line is detached from the lunar surface, leaving a possibility of the T2 entry under magnetic connection left open. Here we report that the protons can access the central wake region that is magnetically connected to the lunar nightside surface, which we categorize into the T2 entry with magnetic connection to the lunar surface (T2MC). Furthermore we show that the energy of the electron beams induced by the proton entry into the wake depends on the magnetic connectivity. Strong electron acceleration (up to several hundred eV to 1keV) along the magnetic field associated with the T2 entry is prominent when the field line has its both ends in the solar wind, that is, when the magnetic field is detached from the lunar surface (i.e. the previously reported T2 entry that we rename to T2MD). On the other hand, no significant electron acceleration is found in the T2MC cases, although an enhancement of the electron flux associated with the T2 proton entry is evident. We also report that the T2 entry process takes place even under radial (B X -dominated) IMF condition. Our results indicate that, while the T2 entry of solar wind protons into the wake itself does not require a special IMF condition but is a rather general phenomenon, the characteristic energy of associated electrons does show a strong dependence on the magnetic connectivity to the lunar surface. [Copyright &y& Elsevier]

Abstract: In the hair of individuals with blood group AB, the level of blood group A glycosphingolipids is much lower than that of blood group B. We hypothesized that in hair, blood group A determinants are converted by α-N-acetylgalactosaminidase (α-NAGA, E.C.3.2.1.49) to H determinants. To address our hypothesis, the relative amount of ABH glycosphingolipids in hairs and nails of normal subjects, patients with Kanzaki disease, and heterozygous carriers of α-NAGA deficiency were analyzed by dot-blotting and enzyme-linked immunosorbent assay. In hair from normal subjects with blood group B, ABH glycosphingolipids consisted of 88% blood group B- and 12% blood group H glycosphingolipids. In blood group A subjects, 14% were group A- and 86% were group H glycosphingolipids. In Kanzaki patients, 81% were blood group A- and 19% were blood group H glycosphingolipids. In 2 α-NAGA deficiency carriers, the ABH glycosphingolipids consisted of 67% blood group A- and 33% blood group H glycosphingolipids. These results indicate that blood group A glycosphingolipids are catabolized to H glycosphingolipids by α-NAGA, resulting in lower levels of blood group A glycosphingolipids in the hair of normal subjects, and α-NAGA deficiency causes accumulation of blood group A glycosphingolipids in the hair of Kanzaki patients. This finding is of clinical relevance because it suggests that hair may be used to diagnose and assess the α-NAGA status of individuals. [Copyright &y& Elsevier]

Wave–particle interactions are fundamental processes in space plasma, and some plasma waves, including electrostatic solitary waves (ESWs), are recognised as broadband noises (BBNs) in the electric field spectral data. Spacecraft observations in recent decades have detected BBNs around the Moon, but the generation mechanism of the BBNs is not fully understood. Here, we study a wake boundary traversal with BBNs observed by Kaguya, which includes an ESW event previously reported by Hashimoto et al. Geophys Res Lett 37:L19204 https://doi.org/10.1029/2010GL044529 (2010). Focusing on the relation between BBNs and electron pitch-angle distribution functions, we show that upward electron beams from the nightside lunar surface are effective for the generation of BBNs, in contrast to the original interpretation by Hashimoto et al. Geophys Res Lett 37:L19204 https://doi.org/10.1029/2010GL044529 (2010) that high-energy electrons accelerated by strong ambipolar electric fields excite ESWs in the region far from the Moon. When the BBNs were observed by the Kaguya spacecraft in the wake boundary, the spacecraft's location was magnetically connected to the nightside lunar surface, and bi-streaming electron distributions of downward-going solar wind strahl component and upward-going field-aligned beams (at ∼ 124 eV) were detected. The interplanetary magnetic field was dominated by a positive B Z (i.e. the northward component), and strahl electrons travelled in the antiparallel direction to the interplanetary magnetic field (i.e. southward), which enabled the strahl electrons to precipitate onto the nightside lunar surface directly. The incident solar wind electrons cause negative charging of the nightside lunar surface, which generates downward electric fields that accelerate electrons from the nightside surface toward higher altitudes along the magnetic field. The bidirectional electron distribution is not a sufficient condition for the BBN generation, and the distribution of upward electron beams seems to be correlated with the BBNs. Ambipolar electric fields in the wake boundary should also contribute to the electron acceleration toward higher altitudes and further intrusion of the solar wind ions into the deeper wake. We suggest that solar wind ion intrusion into the wake boundary is also an important factor that controls the BBN generation by facilitating the influx of solar wind electrons there. [ABSTRACT FROM AUTHOR]

The mass spectrum analyzer (MSA) will perform in situ observations of ions and magnetic fields around Phobos as part of the Martian Moons eXploration (MMX) mission to investigate the origin of the Martian moons and physical processes in the Martian environment. MSA consists of an ion energy mass spectrometer and two magnetometers which will measure velocity distribution functions and mass/charge distributions of low-energy ions and magnetic field vectors, respectively. For the MMX scientific objectives, MSA will observe solar wind ions, those scattered at the Phobos surface, water-related ions generated in the predicted Martian gas torus, secondary ions sputtered from Phobos, and escaping ions from the Martian atmosphere, while monitoring the surrounding magnetic field. MSA will be developed from previous instruments for space plasma missions such as Kaguya, Arase, and BepiColombo/Mio to contribute to the MMX scientific objectives. [ABSTRACT FROM AUTHOR]

The Moon drives observable perturbations in the upstream solar wind in a similar manner to the terrestrial foreshock. Recent observations suggested that lunar dayside electrostatic waves can arise from two different driving mechanisms, both involving reflected particles from lunar crustal magnetic fields. However, their association with the global distribution of lunar magnetic anomalies have not been fully characterized. Here we exploit polar orbiting Kaguya to generate first global maps of electrostatic waves and solar wind electron modification above the day side of the Moon. The maps clearly demonstrate that the two signatures are correlated with lunar crustal magnetic fields. Additionally, we observe different characteristics of electron modification for different interplanetary magnetic field orientations. The lunar crustal magnetic fields cause a wide range of reflected electron and ion intensities, thereby serving as a test bed to investigate the relative roles of reflected particles on wave excitation and particle heating. Plain Language Summary: The Moon drives a variety of waves in the surrounding ionized gas. In this study, we make a world map showing the population of one of these waves, electrostatic waves, on the Moon. The wave map shows a clear pattern resembling the lunar magnetic field map. This suggests that the waves are caused by reflection of charged particles from the localized magnetic field of the Moon. Additionally, we observe a change in incoming electrons from the Sun when the waves are present. Our results demonstrate that the space around the Moon is a useful place to study interactions between particles and waves, which occur in many other places in space. Key Points: We present first global maps of electrostatic waves and solar wind electron modification on the lunar day sideThe wave generation and resulting solar wind electron modification are clearly controlled by lunar crustal magnetic fieldsTwo types of electron‐wave interactions are observed under different interplanetary magnetic field orientations [ABSTRACT FROM AUTHOR]

Mercury has a unique and complex space environment with its weak global magnetic field, intense solar wind, tenuous exosphere, and magnetospheric plasma particles. This complex system makes Mercury an excellent science target to understand effects of the solar wind to planetary environments. In addition, investigating Mercury's dynamic magnetosphere also plays a key role to understand extreme exoplanetary environment and its habitability conditions against strong stellar winds. BepiColombo, a joint mission to Mercury by the European Space Agency and Japan Aerospace Exploration Agency, will address remaining open questions using two spacecraft, Mio and the Mercury Planetary Orbiter. Mio is a spin-stabilized spacecraft designed to investigate Mercury's space environment, with a powerful suite of plasma instruments, a spectral imager for the exosphere, and a dust monitor. Because of strong constraints on operations during its orbiting phase around Mercury, sophisticated observation and downlink plans are required in order to maximize science outputs. This paper gives an overview of the Mio spacecraft and its mission, operations plan, and data handling and archiving. [ABSTRACT FROM AUTHOR]

BepiColombo Mio, also known as the Mercury Magnetospheric Orbiter (MMO), is intended to conduct the first detailed study of the magnetic field and environment of the innermost planet, Mercury, alongside the Mercury Planetary Orbiter (MPO). This orbiter has five payload groups; the MaGnetic Field Investigation (MGF), the Mercury Plasma Particle Experiment (MPPE), the Plasma Wave Investigation (PWI), the Mercury Sodium Atmosphere Spectral Imager (MSASI), and the Mercury Dust Monitor (MDM). These payloads operate through the Mission Data Processor (MDP) that acts as an integrated system for Hermean environmental studies by the in situ observation of charged and energetic neutral particles, magnetic and electric fields, plasma waves, dust, and the remote sensing of radio waves and exospheric emissions. The MDP produces three kinds of coordinated data sets: Survey (L) mode for continuous monitoring, Nominal (M) mode for standard analyses of several hours in length (or more), and Burst (H) mode for analysis based on 4–20-min-interval datasets with the highest cadence. To utilize the limited telemetry bandwidth, nominal- and burst-mode data sets are partially downlinked after selections of data based on L- or L/M-mode data, respectively. Burst-mode data can be taken at preset timings, or by onboard automatic triggering. The MDP functions are implemented and tested on the ground as well as cruising spacecraft; they are responsible for conducting full scientific operations aboard spacecraft. [ABSTRACT FROM AUTHOR]

Microprocesses associated with plasma inhomogeneities are studied on the basis of data from the Investigation of Cusp Irregularities (ICI-3) sounding rocket. The ICI-3 rocket is devoted to investigating a reverse flow event in the cusp F region ionosphere. By numerical stability analysis, it is demonstrated that inhomogeneous-energy-density-driven (IEDD) instability can be a mechanism for the excitation of small-scale plasma inhomogeneities. The Local Intermittency Measure (LIM) method also applied the rocket data to analyze irregular structures of the electric field during rocket flight in the cusp. A qualitative agreement between high values of the growth rates of the IEDD instability and the regions with enhanced LIM is observed. This suggests that IEDD instability is connected to turbulent non-Gaussian processes. [ABSTRACT FROM AUTHOR]

Ion sources using electron impact ionization (EI) methods have been widely accepted in mass spectrometry for planetary exploration missions because of their simplicity. Previous space-borne mass spectrometers were primarily designed with the EI method using rhenium tungsten alloy filaments, enabling up to 100–200 ​μA emission in typical cases. The emission level is desired to be enhanced because the sensitivity of mass spectrometers is a critical requirement for the future in situ mass spectrometry related to the measurement of trace components in planetary samples. In this study, we developed a new high-emission EI ion source using a Y 2 O 3 -coated iridium filament, which has a lower work function than rhenium tungsten alloy. The size of the ion source was 30 ​mm ​× ​26 ​mm ​× ​70 ​mm, and its weight was ∼70 ​g. We confirmed that when consuming ∼3.0 ​W power, the ion source records 1–2 ​mA electrons, which is 10 times greater than the conventional models' electron emission level. We verified the linearity of ionization efficiency and the electron current in the range of 0.1–1 ​mA, which indicates our new model increased the ionization efficiency. We conducted performance tests on the prototype with the 3.0 ​W heating condition, confirming a high ionization efficiency (∼104 ​nA/Pa). In addition, we conducted endurance tests of the ion source and demonstrated the persistence of the ionization efficiency for 30 ​min ​× ​100 cycles. • Y 2 O 3 coated Iridium filament was newly incorporated for space-borne EI ion source. •The size of the ion source was 30 ​mm ​× ​26 ​mm ​× ​70 ​mm, and its weight was ∼70 ​g. •The result showed >2 ​mA electron emission, which is 10-times greater than before. •With ∼3.0 ​W heating, the ion source achieved 104 ​nA/Pa ionization efficiency. •The ionization efficiency kept constant during 30 ​min ​× ​100 cycles endurance test. [ABSTRACT FROM AUTHOR]

Argifin,a 17-membered pentapeptide, inhibits chitinase. As argifinhas properties that render it unsuitable as a drug development candidate,we devised a mechanism to create the structural component of argifinthat bestows the chitinase inhibition and introduce it into a 14-memberedmacrolide scaffold. Here we describe (1) the designed macrolide, whichexhibits ∼200-fold more potent chitinase inhibition than argifin,(2) the binding modes of the macrolide with Serratia marcescenschitinase B, and (3) the computed analysis explaining the reasonfor derivatives displaying increased inhibition compared to argifin,the macrolide aglycone displaying inhibition in a nanomolar range.This promises a class of chitinase inhibitors with novel skeletons,providing innovative insight for drug design and the use of macrolidesas adaptable, flexible templates for use in drug discovery researchand development. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents an on-machine surface profile measurement system for a large mirror to be used on artificial satellites. The measurement system is constructed by mounting a long-stroke length gauge on a commercial rotary grinder for fabrications of mirror profiles. Mounting the length gauge on slides of the rotary grinder enables evaluations of the mirror profiles, which results would be used to compensate profile errors of the mirrors. In the developed system, both positioning errors and tilt misalignments of the length gauge would induce significant measurement errors. In this study, a quantitative alignment method and a compensation method are therefore developed to reduce the measurement errors related to both the positioning errors and tilt misalignments of the length gauge. In addition, a measurement uncertainty of the developed system has been systematically investigated to confirm its feasibility on the mirror profile measurements. The measured results were finally fed back to the mirror profile fabrication so that the profile error could be reduced to less than 5μm. Mirror profiles measured on machine before and after compensation machining are also reported. [Copyright &y& Elsevier]

Abstract: We study an interaction between the solar wind and crustal magnetic fields on the lunar surface using SELENE (Kaguya) data. It has been known that magnetic enhancements are at times detected near the limb external to the lunar wake, which is thus called lunar external magnetic enhancement (LEME), as a result of direct interaction between the solar wind and lunar crustal fields. Although previous observational studies showed that LEMEs in the high solar zenith angle region favor stronger interplanetary magnetic field (IMF) and higher solar wind density, the relation between the IMF and the crustal field orientation has not been taken into account. We show evidence that the relation between the IMF and crustal field orientation is also one of the key factors that control the extent of LEME, focusing on one-day observations at 100km altitude that include data above strong crustal fields around South Pole-Aitken (SPA) basin. Strong LEMEs are detected at 100km altitude around SPA basin under the stronger and northward IMF condition, while they weaken under southward IMF. All LEME''s peaks are located in the region where unperturbed crustal fields at 300km altitude are directed northward while they are less related to unperturbed crustal fields at 100km or lower, which suggests that lunar crustal fields are compressed by the solar wind dynamic pressure, and its large scale component parallel to the IMF is essential to the formation of the LEME. [Copyright &y& Elsevier]

Abstract: Kelvin–Helmholtz instability (KHI) is a fundamental fluid dynamical process that develops in a velocity shear layer. It is excited on the tail-flanks of the Earth''s magnetosphere where the flowing magnetosheath plasma and the stagnant magnetospheric plasma sit adjacent to each other. This instability is thought to induce vortical structures and play an important role in plasma transport there. While KHI vortices have been detected, the earlier observations were performed only on one flank at a time and questions related to dawn–dusk asymmetry were not addressed. Here, we report a case where KHI vortices grow more or less simultaneously and symmetrically on both flanks, despite all the factors that may have broken the symmetry. Yet, energy distributions of ions in and around the vortices show a remarkable dawn–dusk asymmetry. Our results thus suggest that although the initiation and development of the KHI depend primarily on the macroscopic properties of the flow, the observed enhancement of ion energy transport around the dawn side vortices may be linked to microphysical processes including wave-particle interactions. Possible coupling between macro- and micro-scales, if it is at work, suggests a role for KHI not only within the Earth''s magnetosphere (e.g., magnetopause and geomagnetic tail) but also in other regions where shear flows of magnetized plasma play important roles. [Copyright &y& Elsevier]

Abstract: Because the solar wind (SW) flow is usually super-sonic, a fast-mode bow shock (BS) is formed in front of the Earth''s magnetosphere, and the Moon crosses the BS at both dusk and dawn flanks. On the other hand, behind of the Moon along the SW flow forms a tenuous region called lunar wake, where the flow can be sub-Alfvénic (and thus sub-sonic) because of its low-density status. Here we report, with joint measurement by Chang’E-1 and SELENE, that the Earth''s BS surface is drastically deformed in the lunar wake. Despite the quasi-perpendicular shock configuration encountered at dusk flank under the Parker-spiral magnetic field, no clear shock surface can be found in the lunar wake, while instead gradual transition of the magnetic field from the upstream to downstream value was observed for a several-minute interval. This finding suggests that the ‘magnetic ramp’ is highly broadened in the wake where a fast-mode shock is no longer maintained due to the highly reduced density. On the other hand, observations at the 100km altitude on the dayside show that the fast-mode shock is maintained even when the width of the downstream region is smaller than a typical scale length of a perpendicular shock. Our results suggest that the Moon is not so large to eliminate the BS at 100km altitude on the dayside, while the magnetic field associated with the shock structure is drastically affected in the lunar wake. [Copyright &y& Elsevier]

Abstract: The dipeptide N-acetyl-Arg{N ω-(N-methylcarbamoyl)}-N-methyl-Phe(2), which is a part of the natural-product cyclopentapeptide chitinase inhibitor argifin (1), inhibits chitinase B from Serratia marcescens (SmChiB) with a half-maximal inhibitory concentration (IC50) of 3.7μM. Despite the relatively small size of 2, its inhibitory activity is comparable with that of 1 (IC50 =6.4μM). To elucidate the basis for this interesting phenomenon, we investigated the interaction between 2 and SmChiB using a combination of nuclear magnetic resonance spectroscopy and computational methods. The transferred nuclear Overhauser effect (TRNOE) experiment obtained structural information on the SmChiB-bound conformation of 2. The binding mode of 2 and SmChiB was modeled by the novel molecular-docking approach proposed in our laboratory, which can explicitly consider water-mediated hydrogen-bonding interactions in protein-ligand interfaces. The SmChiB-bound conformation of 2 in the resulting model satisfied all proton-proton distance constraints derived from the TRNOE experiment, indicating that our model structure of the 2-SmChiB complex is reasonable. A molecular dynamics (MD) simulation examined the stability of the resultant complex structure and suggested that 2 binds to SmChiB in a similar fashion to the binding mode observed for N ω-(N-methylcarbamoyl)-Arg(1) and N-methyl-Phe(2) of 1 in the crystal structure of the argifin–SmChiB complex. Finally, the binding free energies of 1 and 2 with SmChiB were estimated by the molecular mechanics Poisson–Boltzmann surface area (MM-PBSA) method using the MD trajectory. The MM-PBSA calculation suggested that both 1 and 2 bind to SmChiB with similar affinities, which is consistent with their experimental IC50 values. Energetic analysis revealed that the van der Waals interaction of 2 with SmChiB is much less than that of 1, but is completely compensated by the more favorable contribution of solute entropy and the total electrostatic component. The improved total electrostatic component was derived from more favorable electrostatic interactions. Therefore, we conclude that dipeptide 2 was also better optimized against SmChiB than 1 in an electrostatic point of view. [Copyright &y& Elsevier]

Background and Aim: The risks of peptic ulcer complications increase in association with low-dose aspirin (LDA) use. The endoscopic findings and clinical features of gastroduodenal ulcer have not been thoroughly investigated in patients taking LDA.Method: We classified 1,041 gastroduodenal ulcer patients into three groups [patients taking LDA (group A), patients taking nonaspirin nonsteroidal anti-inflammatory drug (NSAID) (group N), and patients taking neither aspirin nor nonaspirin NSAID (group C)] and 241 bleeding gastroduodenal ulcer patients into three corresponding groups (groups a, n, and c). We investigated the clinical features, endoscopic characteristics, and endoscopic treatment of the hemorrhagic lesion in the gastroduodenal ulcer patients taking LDA and compared them with those of the other groups.Results: The frequency of bleeding events such as hematemesis, melena, and anemia was significantly higher in group A and N than in group C. The percentage of ulcers located in the antrum was higher in group A and N than in group C, and also higher in group a and n than in group c. The percentage of ulcers located in the body, fundus, and cardia was significantly higher in the bleeding patients than in all gastroduodenal ulcer patients. The percentage of cases that required additional endoscopic treatment in group a was higher than in group c. Duration of hospitalization of group a was significantly longer than that of group c.Conclusion: These results indicate that it is very important to prevent LDA-induced gastroduodenal ulcer complications, including bleeding. [ABSTRACT FROM AUTHOR]

Abstract: Human acidic mammalian chitinase (hAMCase) is an attractive target for developing anti-asthma medications. We used a variety of computational methods to investigate the interaction between hAMCase and the natural-product cyclopentapeptide chitinase inhibitor argifin. The three-dimensional structure of hAMCase was first constructed using homology modeling. The interaction mode and binding free energy between argifin and hAMCase were then examined by the molecular-docking calculation and the molecular mechanics Poisson–Boltzmann surface area method combined with molecular dynamics simulation, respectively. The results suggested that argifin binds to hAMCase in a similar fashion to the interaction mode observed in the crystal structure of argifin-human chitotriosidase complex, and possesses inhibitory activity against hAMCase in the micromolar range. We further designed argifin derivatives expected to be selective for hAMCase. [Copyright &y& Elsevier]

Abstract: Argifin, a novel pentapeptide chitinase inhibitor isolated from Gliocladium fungal culture, is a promising candidate for the development of new fungicides, insecticides, and anti-asthma medications. In this study, we undertook rational molecular design of argifin-derivatives and tested them against chitinase B from Serratia marcescens (SmChiB). The work involved molecular dynamics simulation with explicit water molecules, the molecular docking calculation, and free-energy analysis using the molecular mechanics Poisson–Boltzmann surface area method. The custom-designed derivatives were synthesized via effective solid phase synthesis, developed recently in our laboratory, and their inhibitory activities were measured against SmChiB. Finally, we identified and obtained a derivative which exhibited 28-fold more inhibition than argifin itself, a compound in which the d-Ala(5) of argifin was replaced with d-Leu and the 4-benzylpiperdine was attached to l-Asp(4). [Copyright &y& Elsevier]

Abstract: An effective solid phase synthesis of Argifin, providing subsequent access to effective synthesis of analogues, was developed in 13% overall yield, as well as elucidating structure–activity relationships. The novel acyclic peptide 18b, prepared from a synthetic intermediate of Argifin, was found to be 70 times more potent as an inhibitor of Serratia marcescens chitinases B than Argifin itself [Copyright &y& Elsevier]

Aim: A large cohort study in Japan revealed that the specific viral profile may influence the fulminant outcome in acute hepatitis B virus (HBV) infections, while the genetic influence on outcome has not been clarified in patients with acute exacerbation of chronic liver disease caused by HBV. We experienced a case of fatal liver failure that developed as the result of chronic HBV infection. To determine possible genetic factor involving acute exacerbation, genetic analysis of serum from the patient and his siblings was performed. Methods: HBV subgenotype as well as pre-core/core-promoter mutations of samples mentioned above were determined. Results: Patient had HBV-Bj with pre-core (1896/1899) and core-promoter (1762/1764) mutations, the genomic profile frequently seen in fulminant hepatitis caused by acute HBV infection. Conclusion: This result suggests that determination of the HBV subgenotype and pre-core/core promoter mutations could provide a rationale for development of a treatment strategy in asymptomatic HBV carriers. [ABSTRACT FROM AUTHOR]

Aim: The effect of dietary cholesterol on plasma cholesterol concentrations varies widely among individuals. Recent studies suggest that the synthesis of oxysterols is up-regulated when tissue cholesterol is saturated. The present study was undertaken to test the hypothesis that a serum high concentration of 27-hydroxycholesterol, one of the oxysterols, reflects positive cholesterol balance in the body and predicts intolerance to a high-cholesterol diet. Methods: In 30 subjects, 750 mg/day of cholesterol was added for 4 weeks to the ordinary diet. Blood samples were collected at the start and finish of the supplementation. Serum sterol and oxysterol concentrations were measured by high-resolution GC-MS. Results: A receiver operating characteristic curve was drawn and the cutoff point (80 ng/mg cholesterol) was chosen to maximize sensitivity (81.3%) and specificity (64.3%) for predicting a positive change of LDL cholesterol concentration after cholesterol loading. Subjects with higher serum 27-hydroxycholesterol concentrations (≥ 80 ng/mg cholesterol) showed significantly ( P < 0.05) high values for the change of LDL cholesterol concentration (+7.4 ± 3.4%, mean ± SEM, n = 17) compared with those with lower 27-hydroxycholesterol levels (−5.3 ± 2.7%, n = 13). Conclusions: In subjects with high serum 27-hydroxycholesterol concentrations were unable to adapt to a high-cholesterol diet. The concentration of serum 27-hydroxycholesterol appears to reflect cholesterol saturation in the body and predicts to some extent a responsiveness to dietary cholesterol. [ABSTRACT FROM AUTHOR]

We examine photoelectron distributions detected by the low-energy-particle (LEP) instrument onboard the GEOTALL spacecraft by means of both data analysis and numerical simulations. Statistical data analysis shows asymmetries in the photoelectron distributions. For photoelectrons incident normal to the spacecraft spin axis, a higher flux is observed in the dawnward than in the duskward sector of the LEP. The distribution significantly depends on the ratio of the photoelectron energy to the spacecraft potential. Our numerical simulations reveal that the asymmetry is caused by the electrostatic potential around the thin antenna located at +18° anticlockwise (viewed from the top) relative to the LEP. Photoelectrons in the dawnward sector are preferentially carried from the sunlit surface by this potential. For upward/downward incident photoelectrons, a higher flux of upward photoelectrons is observed in the antisunward than in the sunward sector, whereas downward photoelectrons show a weak asymmetry. Our numerical simulations demonstrate that the greater flux of upward photoelectrons is caused by the electrons emitted from the sunlit surface; they are attracted to the antisunward sector. Based on these results, the asymmetries in the photoelectron distribution measured around GEOTAIL are found to be caused by the asymmetric positioning of the thin antennas relative to the LEP. [ABSTRACT FROM AUTHOR]