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Pulsating Aurora (PsA) is one of the major classes of diffuse aurora associated with precipitation of a few to a few tens of keV electrons from the magnetosphere. Recent studies suggested that, during PsA, more energetic (i.e., sub‐relativistic/relativistic) electrons precipitate into the ionosphere at the same time. Those electrons are considered to be scattered at the higher latitude part of the magnetosphere by whistler‐mode chorus waves propagating away from the magnetic equator. However, there have been no actual cases of simultaneous observations of precipitating electrons causing PsA (PsA electrons) and chorus waves propagating toward higher latitudes; thus, we still do not quite well understand under what conditions PsA electrons become harder and precipitate to lower altitudes. To address this question, we have investigated an extended interval of PsA on 12 January 2021, during which simultaneous observations with the Arase satellite, ground‐based all‐sky imagers and the European Incoherent SCATter (EISCAT) radar were conducted. We found that, when the PsA shape became patchy, the PsA electron energy increased and Arase detected intense chorus waves at magnetic latitudes above 20°, indicating the propagation of chorus waves up to higher latitudes along the field line. A direct comparison between the irregularities of the magnetospheric electron density and the emission intensity of PsA patches at the footprint of the satellite suggests that the PsA morphology and the energy of PsA electrons are determined by the presence of "magnetospheric density ducts," which allow chorus waves to travel to higher latitudes and thereby precipitate more energetic electrons. Plain Language Summary: Pulsating Aurora (PsA) is a kind of diffuse aurora associated with periodic precipitation of energetic electrons from the near‐Earth space into the atmosphere. Recent research has shown that, during PsA events, energetic particles at the sub‐relativistic energy range precipitate into the atmosphere. We speculate that such particles are scattered by wave‐particle resonance with natural electromagnetic waves, called chorus waves, at higher magnetic latitude regions. However, there has been no experimental case of PsA during which propagation of the chorus waves to higher magnetic latitudes was confirmed; thus, we still do not fully understand when and why PsA electrons become more energetic. Here, we investigate a PsA event on 12 January 2021, simultaneously observed by the Arase satellite, ground‐based all‐sky imagers and the European Incoherent SCATter (EISCAT) radar. We found that, when the PsA shape was patchy, the energy of precipitating electrons increased and chorus waves were observed at high latitudes in the magnetosphere. Comparing the magnetospheric electron density with the PsA brightness seen from the ground, we suggest that both the PsA shape and the energy of precipitating electrons were influenced by the so‐called magnetospheric ducts, which guide chorus waves to high‐latitudes regions where they interact with more energetic electrons. Key Points: Examined simultaneous observations of Pulsating Aurora (PsA) with the Arase satellite, ground‐based all‐sky imagers, and the EISCAT radarFound a relationship among the patchy PsA, the enhanced energy of PsA electrons, and the chorus wave propagation to high‐latitudes (>20°)Arase observations suggest that the observed relationship can be explained by the ducted propagation of chorus waves [ABSTRACT FROM AUTHOR]

Patients with chronic lung disease, obesity, and other co-morbid conditions are at increased risk of severe illness and death when infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Hypercapnia, the elevation of CO2 in blood and tissue, commonly occurs in patients with severe acute and chronic lung disease, including those with pulmonary infections, and is also associated with high mortality risk. We previously reported that hypercapnia increases viral replication and mortality of influenza A virus infection in mice. We have also shown that culture in elevated CO2 upregulates expression of cholesterol synthesis genes in primary human bronchial epithelial cells. Interestingly, factors that increase the cholesterol content of lipid rafts and lipid droplets, platforms for viral entry and assembly, enhance SARS-CoV-2 infection. In the current study, we investigated the effects of hypercapnia on ACE2 expression and entry of SARS-CoV-2 pseudovirus (p-SARS-CoV-2) into airway epithelial cells. We found that hypercapnia increased ACE2 expression and p-SARS-CoV-2 uptake by airway epithelium in mice, and in cultured VERO and human bronchial epithelial cells. Hypercapnia also increased total cellular and lipid raft-associated cholesterol in epithelial cells. Moreover, reducing cholesterol synthesis with inhibitors of sterol regulatory element binding protein 2 (SREBP2) or statins, and depletion of cellular cholesterol, each blocked the hypercapnia-induced increases in ACE2 expression and p-SARSCoV-2 entry into epithelial cells. Cigarette smoke extract (CSE) also increased ACE2 expression, p-SARS-CoV-2 entry and cholesterol accumulation in epithelial cells, an effect not additive to that of hypercapnia, but also inhibited by statins. These findings reveal a mechanism that may account, in part, for poor clinical outcomes of SARS-CoV-2 infection in patients with advanced lung disease and hypercapnia, and in those who smoke cigarettes. Further, our results suggest the possibility that cholesterol-lowering therapies may be of particular benefit in patients with hypercapnia when exposed to or infected with SARS-CoV-2. [ABSTRACT FROM AUTHOR]

A physical mechanism to produce pulsating aurora (PsA) has been considered to be the interaction of the electron and the chorus wave generated near the equatorial plane of the magnetosphere. A recent observation of high temporal resolution of chorus waves by the Arase satellite revealed that the presence or absence of the internal modulation of PsA, which is a characteristic sub‐second scintillation at 3 ± 1 Hz within each optical pulsation, is closely related to the discreteness of the element structure of the chorus wave. However, it is still unclear what parameters (or conditions) control the discreteness of the element and the existence of the internal modulation of PsA. In this study, we discuss parameters that determine the presence or absence of the internal modulation of PsA and element structure of chorus by showing a conjugate observation of PsA/chorus by ground‐based cameras and the Arase satellite. During the event, the occurrence of internal modulation increased temporally. The wave data from the satellite show that the repetitive frequency of elements was ∼6 Hz when the internal modulation was indistinct, while the repetitive frequency was ∼3 Hz when the internal modulation was distinct. The particle measurements suggest that this difference was caused by changes in the density and the temperature anisotropy of the hot electron. The internal modulation was clearly observed when the density of hot electrons decreased and the temperature anisotropy relaxed after the injection. Observations of internal modulations from the ground might allow us to estimate the parameters such as energetic electron density and temperature anisotropy in the magnetosphere. Key Points: We analyzed a pulsating aurora (PsA) event in which the occurrence frequency of internal modulation increased significantly with timeA conjugate observation with Arase suggests that a sudden enhancement of energetic electrons by the injection caused non‐modulated PsAsThe internal modulation may be more often observed after the injection as the density of energetic electrons decreases in the magnetosphere [ABSTRACT FROM AUTHOR]

A new empirical density model is developed for the inner zone between 1 < L < 3 using plasma densities inferred from the upper hybrid resonance on Arase, and hiss‐inferred density values from Van Allen Probes. The Van Allen Probes hiss‐inferred densities are first recalibrated and validated against Arase observations, using both a conjunction event and statistical analyses. The newly developed density model includes dependencies on L, magnetic latitude, and magnetic local time (MLT). Between 1.5 < L < 3.0, the equatorial density variation with L is shown to be equivalent to that of the Ozhogin et al. (2012, https://doi.org/10.1029/2011JA017330) model. However, for L < 1.5, this dependence changes as the plasma density increases at a faster rate with decreasing L. The latitudinal dependence of the plasma density is shown to present a flatter profile than previous models, meaning lower densities extend to higher latitudes. This dependence is well‐modeled by updated fitting coefficients. A clear MLT dependence of the plasma density is identified, which was not found or included in some previous models. This variation is consistent with the diurnal variation of the ionosphere, peaking near MLT = 14 and becoming larger in amplitude with decreasing L. A function describing this MLT dependence is presented. Overall, the new L, latitude, and MLT‐dependent empirical model can provide density values in areas outside the validity region of many previous models, making it a useful resource for accurately determining diffusion coefficients and predicting electron dynamics and their lifetimes in the inner radiation belt. Key Points: Radiation Belt Storm Probes and Arase data are used to build a new empirical plasma density model for the inner zone, including L, latitude, and magnetic local time (MLT) dependenciesMLT dependence consistent with diurnal variation of ionosphere. Variation is largest in amplitude at low L, but persists out to L = 3New model provides density in areas outside previous model bounds, making it a useful resource for modeling inner radiation belt dynamics [ABSTRACT FROM AUTHOR]

Background: Follicular dendritic cell sarcoma is a rare stromal tumor with no standard treatment. However, some reports have revealed that follicular dendritic cell sarcoma has an inflammatory pseudotumor variant associated with Epstein–Barr virus infection that has a relatively good prognosis. In this report, we present a case of a resected inflammatory pseudotumor variant of follicular dendritic cell sarcoma of the liver, and have reviewed the literature on the clinicopathological, molecular, and genomic features of this tumor. Case presentation: The inflammatory pseudotumor variant of follicular dendritic cell sarcoma originates only in the liver or spleen, causes no symptoms, and is more common in middle-aged Asian women. It has no characteristic imaging features, which partially explains why the inflammatory pseudotumor variant of follicular dendritic cell sarcoma is difficult to diagnose. Pathologically, the inflammatory pseudotumor variant of follicular dendritic cell sarcoma has spindle cells mixed with inflammatory cells and is variably positive for follicular dendritic cell markers (CD21, CD23, and CD35) and Epstein–Barr virus-encoded RNA. On genetic analysis, patients with this tumor high levels of latent membrane protein 1 gene expression and extremely low levels of host C–X–C Chemokine Receptor type 7 gene expression, indicating that the inflammatory pseudotumor variant of follicular dendritic cell sarcoma has a latent Epstein–Barr virus type 2 infection. Conclusions: The inflammatory pseudotumor variant of follicular dendritic cell sarcoma is an Epstein–Barr virus-associated tumor and a favorable prognosis by surgical resection, similar to Epstein–Barr virus-associated gastric cancer. [ABSTRACT FROM AUTHOR]

Currently, biological disease-modifying anti-rheumatic drugs (bDMARDs) with different modes of action [tumour necrosis factor inhibitor (TNFi), interleukin-6 receptor inhibitor (IL-6Ri), or cytotoxic T-lymphocyte antigen 4–immunoglobulin (CTLA4-Ig)] are used in clinical practice to treat rheumatoid arthritis (RA). However, it is unclear which type of bDMARD is the most efficacious for a specific clinical situation. C-reactive protein (CRP) is an acute-phase reactant driven by IL-6 signalling. Here, we aimed to establish whether therapeutic efficacy differs between IL-6Ri and other bDMARDs with alternative modes of action in RA patients according to their CRP level. RA patients treated with bDMARDs were enrolled from an observational multicentre registry in Japan. Patients were classified into three groups according to baseline CRP tertiles. The overall 3 year retention rates of each bDMARD category were assessed. The Clinical Disease Activity Index (CDAI) was also assessed before and 3, 6, and 12 months after bDMARD initiation. A total of 1438 RA patients were included and classified into three groups according to tertiles of baseline CRP levels (CRP1, 0–0.3; CRP2, 0.3–1.8; CRP3, 1.8–18.4 mg/dL). In CRP3, the overall 3 year drug retention rates were significantly higher for IL-6Ri than for TNFi and CTLA4-Ig (77.5 vs 48.2 vs 67.3, respectively). No significant difference was evident in terms of CDAI 12 months after bDMARD initiation in CRP1–CRP3. IL-6Ri may be a favourable therapeutic option over TNFi and CTLA4-Ig in RA patients with high CRP levels. [ABSTRACT FROM AUTHOR]

We propose an accurate calibration method for short‐time waveform signals passed through a linear time‐invariant (LTI) system that has a non‐negligible group delay. Typically, the calibration process of waveform data is expressed by the deconvolution in the time domain, and there is an equivalent operation in the frequency domain with the Fourier transform. For the short‐time data, if the short‐time Fourier transform is applied to the waveform data in the calibration process, multiplying the data by a window function is highly recommended to reduce side‐lobe effects. However, the multiplied window function is also modified in the calibration process. We analyzed the modification mathematically and derived a method to eliminate the modification of the multiplied window function. In the method, calibrated data in the frequency domain are inverse‐transformed into waveform data at each frequency, divided by a modified window function at each frequency, and accumulated over the frequencies. The principle of this method derived quantitatively indicates that the calibration accuracy depends on the transfer function of the system, frequency resolution of the Fourier transform, type of the window function, and typical frequency of the waveform data. Compared with conventional calibration methods, the proposed method provides more accurate results in various cases. This method should be useful for the calibration of general radio wave signals passed through LTI systems as well as for the calibration of plasma waves observed in space. Key Points: We propose a calibration method using short‐time Fourier transform (STFT) for waveform data, such as plasma waves observed in spaceThe accuracy of the method is evaluated using the transfer functions of well‐known filters and frequency‐fixed sinusoidal waveformsThe proposed method provides the most accurately calibrated data compared with conventional methods using STFT [ABSTRACT FROM AUTHOR]

Microbursts are impulsive (<1 s) injections of electrons into the atmosphere, thought to be caused by nonlinear scattering by chorus waves. Although attempts have been made to quantify their contribution to outer belt electron loss, the uncertainty in the overall size and duration of the microburst region is typically large, so that their contribution to outer belt loss is uncertain. We combine datasets that measure chorus waves (Van Allen Probes [RBSP], Arase, ground‐based VLF stations) and microburst (>30 keV) precipitation (FIREBIRD II and AC6 CubeSats, POES) to determine the size of the microburst‐producing chorus source region beginning on 5 December 2017. We estimate that the long‐lasting (∼30 hr) microburst‐producing chorus region extends from 4 to 8 Δ ${\Delta}$MLT and 2–5 Δ ${\Delta}$L. We conclude that microbursts likely represent a major loss source of outer radiation belt electrons for this event. Plain Language Summary: Microbursts are short‐duration (<1 s) bursts of electrons that precipitate from the magnetosphere into the atmosphere. Microbursts are thought to be a result of scattering by a plasma wave called chorus. Attempts have been made to understand the contribution microburst precipitation has on electron loss, which helps the outer radiation belt recover after enhancements during storms. The contribution depends on the overall size and duration of the microburst region. We combine datasets that measure chorus waves and microburst precipitation to determine the size and duration of a microburst region beginning on 5 December 2017. Our results show that microbursts are likely a significant source of electron loss. Key Points: We use multipoint observations to estimate the size of a long‐lasting microburst‐producing chorus region beginning on 5 December 2017We estimate that the microburst‐producing chorus region for this event extends from 4 to 8 Δ ${\Delta}$MLT and 2–5 Δ ${\Delta}$LMicroburst precipitation from this event likely constitutes a major source of electron loss from the outer radiation belt [ABSTRACT FROM AUTHOR]

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 ∼ 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. [ABSTRACT FROM AUTHOR]

Plasmaspheric hiss can cause energetic electron precipitation from the magnetosphere to the Earth's upper atmosphere and affect the ionospheric electron density profiles. In this study, we use Arase satellite measurements in the dayside plasmasphere to model the electron precipitation and the resultant ionospheric response, and compare the results to the electron density measured by the Poker Flat Incoherent Scatter Radar (PFISR). We analyzed two close conjunction events between Arase and PFISR at L ∼ 6 in the afternoon sector, when Arase was in the outer plasmasphere and traveled into the plasmaspheric plumes. Modest or strong hiss waves were observed with amplitudes higher than 50 pT during both events. Quasilinear modeling suggests that the hiss waves could cause intense electron precipitation ranging from several keV to several hundred keV energies. The electron density profiles at 60–90 km modeled by the Boulder Electron Radiation to Ionization (BERI) model suggest significant electron density enhancements due to the precipitating electrons. PFISR simultaneously observed electron density enhancements during both events, and provided evidence for the electron precipitation at altitudes down to <70 km. The temporal modulation of hiss caused the modulated density profiles in BERI modeling, but was not evident in PFISR observations. The modeled altitude profiles of the perturbed electron density overall agree with PFISR observation. At altitudes below 75 km, the modeled electron densities are lower than the observation, suggesting additional high energy electron precipitation possibly due to low frequency (<50 Hz) waves or hiss wave powers ducted to high latitudes. Key Points: Two Poker Flat Incoherent Scatter Radar (PFISR)‐Arase conjunction events are identified at the dayside plasmasphere when hiss wave amplitudes reach 50–100 pT at L ∼ 6Hiss‐driven electron precipitation obtained from quasilinear simulation is used to model ionospheric density profiles at 60–90 km altitudeModeled electron densities overall agree with PFISR observations with differences in the temporal modulation and at altitudes below 75 km [ABSTRACT FROM AUTHOR]

Inner magnetospheric electrons are precipitated in the ionosphere via pitch‐angle (PA) scattering by lower band chorus (LBC), upper band chorus (UBC), and electrostatic electron cyclotron harmonic (ECH) waves. However, the PA scattering efficiency of low‐energy electrons (0.1–10 keV) has not been investigated via in situ observations because of difficulties in flux measurements within loss cones at the magnetosphere. In this study, we demonstrate that LBC, UBC, and ECH waves contribute to PA scattering of electrons at different energy ranges using the Arase (ERG) satellite observation data and successively detected the moderate loss cone filling, that is, approaching strong diffusion. Approaching strong diffusion by LBC, UBC, and ECH waves occurred at ∼2–20 keV, ∼1–10 keV, and ∼0.1–2 keV, respectively. The occurrence rate of the approaching strong diffusion by high‐amplitude LBC (>50 pT), UBC (>20 pT), and ECH (>10 mV/m) waves, respectively, reached ∼70%, ∼40%, and ∼30% higher than that without simultaneous wave activity. The energy range in which the occurrence rate was high agreed with the range where the PA diffusion rate of each wave exceeded the strong diffusion level based on the quasilinear theory. Key Points: The pitch‐angle scattering efficiencies by plasma waves are statistically investigated using in situ observationsLower band chorus waves caused approaching strong diffusion with the highest occurrence rate in the energy range of ∼2–20 keVElectrostatic electron cyclotron harmonic waves could contribute approaching strong diffusion in the ∼0.1–1 keV energy range [ABSTRACT FROM AUTHOR]

We examined the growth and propagation of fine‐structured electromagnetic ion cyclotron (EMIC) waves related to time‐varying density irregularities using multipoint measurement data observed by Arase, Van Allen Probe A, and two ground‐based induction magnetometers (Gakona and Dawson) during a field line conjunction event on April 18, 2019. We analyzed the wave data obtained by the aforementioned spacecraft and stations, and found that the appearance of fine structures in the observed EMIC waves clearly coincided with the ambient electron density irregularities in the magnetosphere, which can cause periodic wave growth and waveguiding on their propagation. Furthermore, we found that the latitudinal widths of the EMIC wave activity region and the wave propagation duct were ∼185 km and less than 80 km at an auroral altitude of 100 km, respectively. We also found thermal ion heating (<200 $< 200$ eV/q) during the EMIC wave activity. Plain Language Summary: Electromagnetic ion cyclotron (EMIC) waves are an important plasma waves that control energetic ion and relativistic electron precipitations in the terrestrial inner magnetosphere. We investigated the growth and propagation of fine‐structured EMIC waves observed simultaneously by two spacecraft (Japanese Arase and U.S. Van Allen Probe A) and two ground stations (Gakona and Dawson). The two spacecraft orbited along the same field line, and we measured the same fine‐structured EMIC waves in different geomagnetic latitude regions. The same EMIC waves were observed at the two ground stations located near the magnetic footprints of the two spacecraft. We report that the periodic growth of the observed EMIC waves was associated with the time‐varying electron density irregularity in the midlatitude region. Additionally, we analyzed the spatial scale of the observed EMIC waves and their contribution to the thermal ion heating. Key Points: The simultaneous multipoint observation of fine‐structured electromagnetic ion cyclotron (EMIC) waves was achieved by Arase, Van Allen Probe, and two ground‐based stationsThe growth of the observed fine‐structured EMIC waves was associated with ambient electron density irregularities in the midlatitudesWe investigated the spatial scale of the observed EMIC waves and their contribution to ion heating by utilizing the multipoint measurement [ABSTRACT FROM AUTHOR]

Background: The aim of this study was to assess the long-term annual functional results and quality of life (QOL) after laparoscopic ventral rectopexy (LVR) for rectoanal intussusception (RAI) and/or rectocele. Methods: This study was a retrospective analysis of prospectively collected data. The study was conducted on patients who underwent LVR for RAI and/or rectocele at our institution between February 2012 and July 2015. The Fecal Incontinence Severity Index (FISI), Constipation Scoring System (CSS), and QOL instruments (i.e., 36-item Short-form Health Survey [SF-36], Patient Assessment of Constipation-QOL [PAC-QOL] scale, and Fecal Incontinence-QOL [FIQL]) were administered before and annually after surgery. The sustainability of substantial symptom improvement (reduction of at least 50% in CSS or FISI scores) postoperatively was evaluated. Results: Fifty-one patients (median age 76 [range 60–93] years, 48 women [94%]) were analyzed. No mortality or major morbidity occurred. After a median follow-up of 60 months (range 12–84 months), no mesh-related complications occurred. The median CSS and FISI scores were significantly reduced at 1 year and remained significantly reduced for 7 years. In patients who reported symptom scores ≥ 3 times postoperatively, sustained improvement of constipation and fecal incontinence was found in about 50% (18/38) and 75% (26/35) of relevant patients, respectively. All PAC-QOL and FIQL scales significantly improved over time for 5 years. Of the SF-36 scales, four showed significant improvement at 1 year but none was significantly improved after 3 years, except for the social functioning scale. Conclusions: LVR for RAI and/or rectocele was associated with low morbidity and long-term improvement in symptom-specific QOL. The sustainability of postoperative improvement in fecal incontinence was satisfactory, and that in constipation was fair. [ABSTRACT FROM AUTHOR]

Resonant interactions of energetic electrons with electromagnetic whistler‐mode waves (whistlers) contribute significantly to the dynamics of electron fluxes in Earth's outer radiation belt. At low geomagnetic latitudes, these waves are very effective in pitch angle scattering and precipitation into the ionosphere of low equatorial pitch angle, tens of keV electrons and acceleration of high equatorial pitch angle electrons to relativistic energies. Relativistic (hundreds of keV), electrons may also be precipitated by resonant interaction with whistlers, but this requires waves propagating quasi‐parallel without significant intensity decrease to high latitudes where they can resonate with higher energy low equatorial pitch angle electrons than at the equator. Wave propagation away from the equatorial source region in a non‐uniform magnetic field leads to ray divergence from the originally field‐aligned direction and efficient wave damping by Landau resonance with suprathermal electrons, reducing the wave ability to scatter electrons at high latitudes. However, wave propagation can become ducted along field‐aligned density peaks (ducts), preventing ray divergence and wave damping. Such ducting may therefore result in significant relativistic electron precipitation. We present evidence that ducted whistlers efficiently precipitate relativistic electrons. We employ simultaneous near‐equatorial and ground‐based measurements of whistlers and low‐altitude electron precipitation measurements by ELFIN CubeSat. We show that ducted waves (appearing on the ground) efficiently scatter relativistic electrons into the loss cone, contrary to non‐ducted waves (absent on the ground) precipitating only <150 keV electrons. Our results indicate that ducted whistlers may be quite significant for relativistic electron losses; they should be further studied statistically and possibly incorporated in radiation belt models. Key Points: Near‐equatorial and ground‐based measurements of whistler‐mode waves are accompanied by relativistic electron precipitationIn the presence (absence) of ducted wave propagation, as monitored by propagation to the ground, the precipitating electron energies are above (below) 150 keVDucted whistler‐mode waves may play a key role in relativistic electron loss in the inner magnetosphere [ABSTRACT FROM AUTHOR]

The 11th edition of the "Japanese Classification of Esophageal Cancer" by the Japan Esophageal Society (JES) and the 8th edition of the American Joint Committee on Cancer (AJCC)/Union for International Cancer Control (UICC) "Cancer Staging Manual" are two separate classification systems both widely used for the clinical and pathological staging of esophageal cancer. Furthermore, the lymph node stations from these classification systems are combined for research purposes in the multinational TIGER study, which investigates the distribution pattern of lymph node metastases. The existing classification systems greatly differ with regard to number, location and anatomical boundaries of locoregional lymph node stations. The differences in these classifications cause significant heterogeneity in studies on lymph node metastases in esophageal cancer. This makes data interpretation difficult and comparison of studies challenging. In this article, we propose a match for these two commonly used classification systems and additionally for the TIGER study classification, in order to be able to compare results of studies and exchange knowledge and to make steps towards one global uniform classification system for all patients with esophageal cancer. [ABSTRACT FROM AUTHOR]

Measurements of electromagnetic waves in space plasmas are an important tool for our understanding of physical processes in this environment. Inter‐calibration of data from different spacecraft missions is necessary for combining their measurements in empirical models or case studies. We show results collected during a close conjunction of the Van Allen Probes and Arase spacecraft. The inter‐calibration is based on a fortuitous case of common observations of strong whistlers at frequencies between a few hundred hertz and 10 kHz, which are generated by the same lightning strokes and which propagate along very similar paths to the two spacecraft. Measured amplitudes of the magnetic field fluctuations are the same within ∼14% precision of our analysis, corresponding to 1.2 dB. Currently, archived electric field measurements show twice larger amplitudes on Arase compared to Van Allen Probes but they start to match within ∼33% precision (2.5 dB) once the newest results on the interface of the antennas to the surrounding plasma are included in the calibration procedures. Ray tracing simulations help us to build a consistent scenario of wave propagation to both spacecraft reflected by a successful inter‐calibration of the polarization and propagation parameters obtained from multicomponent measurements. We succeed in linking the spacecraft observations to localizations of lightning return strokes by two different ground‐based networks which independently verify the correctness of the Universal Time tags of waveform measurements by both spacecraft missions, with an uncertainty better than 10 ms. Key Points: Measurements of electromagnetic waves on Van Allen Probes and Arase are inter‐calibrated with intense whistlers during a close conjunctionMagnetic search coil measurements are the same within 14%, polarization and propagation parameters are consistent, timing is within 10 msElectric field amplitudes match within 33% when we include the newest results on antenna‐plasma interface with measured plasma densities [ABSTRACT FROM AUTHOR]

This study reports a relation between electron flux modulations and chorus emissions by using correlation analysis. On April 18, 2017, Arase observed an enhancement of electron fluxes and intensification of banded chorus emissions at the same time. A result of the analysis shows that both the upper‐band and lower‐band chorus emissions have good correlations with field‐aligned electron fluxes that satisfy their resonance conditions. This indicates simultaneous interactions with both the emission bands and electrons, resulting in electron pitch‐angle scattering toward the magnetic field direction. In addition, low‐energy electron fluxes in the perpendicular direction also show positive correlations with the chorus intensities, probably because the chorus emissions are modulated by a fluctuation of perpendicular low‐energy electron fluxes. Plain Language Summary: Scientists have believed that pulsating auroras in the polar regions originate in precipitating electrons that are caused by a wave‐particle interaction in the magnetosphere. Recent observational studies show direct evidence that chorus waves near the magnetic equator scatter local magnetospheric electrons, which are then streaming along the field line down to the ionosphere to generate aurora pulsation in response to modulation of the chorus emissions. Chorus waves usually have two distinct frequency bands, that is, upper band and lower band, but it had not been investigated that how two emission bands interact with electrons. In this study, we analyzed Arase satellite's observation data and identified good correlations between field‐aligned electron fluxes and intensities of the upper‐band and lower‐band emissions. This result indicates that pitch‐angle scattering of electrons takes place by both chorus emission bands simultaneously. Key Points: Arase observed intense banded chorus emissions near the magnetic equator simultaneously with an electron flux enhancementParallel electron fluxes show good correlations with intensities of both the upper‐band and the lower‐band chorus wavesThe positive correlation indicates pitch‐angle scattering of electrons by the chorus waves toward the magnetic field direction [ABSTRACT FROM AUTHOR]

Pulsating aurorae (PsA) are caused by the intermittent precipitations of magnetospheric electrons (energies of a few keV to a few tens of keV) through wave-particle interactions, thereby depositing most of their energy at altitudes ~ 100 km. However, the maximum energy of precipitated electrons and its impacts on the atmosphere are unknown. Herein, we report unique observations by the European Incoherent Scatter (EISCAT) radar showing electron precipitations ranging from a few hundred keV to a few MeV during a PsA associated with a weak geomagnetic storm. Simultaneously, the Arase spacecraft has observed intense whistler-mode chorus waves at the conjugate location along magnetic field lines. A computer simulation based on the EISCAT observations shows immediate catalytic ozone depletion at the mesospheric altitudes. Since PsA occurs frequently, often in daily basis, and extends its impact over large MLT areas, we anticipate that the PsA possesses a significant forcing to the mesospheric ozone chemistry in high latitudes through high energy electron precipitations. Therefore, the generation of PsA results in the depletion of mesospheric ozone through high-energy electron precipitations caused by whistler-mode chorus waves, which are similar to the well-known effect due to solar energetic protons triggered by solar flares. [ABSTRACT FROM AUTHOR]

We developed an in-situ direct measurement technique for the electric field antenna impedance using onboard signal processing. Antenna impedance is an important parameter for observed electric field calibration. Because it changes depending on local plasma parameters, in-situ measurements along the orbit are essential for obtaining precise electric field calibration. We installed the onboard signal calibration function (SWCAL) as a part of the onboard software of the plasma wave experiment (PWE) aboard Arase and performed more than 5,500 measurements in the inner magnetosphere from March 2017 to March 2020. The measured the antenna capacitance along the orbit of Arase, which is important for AC electric field calibration. We found that the measured antenna capacitance varies between 70 and 160 pF depending on the ambient electron density. Further, the effects of the antenna impedance on the AC electric field calibration were evaluated. Results indicated that the observed electric field data include ambiguity of up to 7.8 dB and 17° in the main target frequency range of the waveform capture/onboard frequency analyzer of PWE. This ambiguity can be calibrated by considering the real antenna impedance effects measured using SWCAL. [ABSTRACT FROM AUTHOR]

The temporal variation of the energetic electron flux distribution caused by whistler mode chorus waves through the cyclotron resonant interaction provides crucial information on how electrons are accelerated in the Earth's inner magnetosphere. This study employs a data-driven test-particle simulation which demonstrates that the rapid change of energetic electron distribution observed by the Arase satellite cannot be simply explained by a quasi-linear diffusion mechanism, but is essentially caused by nonlinear scattering: the phase trapping and the phase dislocation. In response to upper-band whistler chorus bursts, multiple nonlinear interactions finally achieve an efficient flux enhancement of electrons on a time scale of the chorus burst. A quasi-linear diffusion model tends to underestimate the flux enhancement of energetic electrons as compared with a model based on the realistic dynamic frequency spectrum of whistler waves. It is concluded that the nonlinear phase trapping plays an important role in the rapid flux enhancement of energetic electrons observed by Arase. [ABSTRACT FROM AUTHOR]

Recent analyses of high-time resolution ground-based optical observations of pulsating aurora (PsA) have reported that the brightness of PsA sometimes decreases below the diffuse background level immediately after the ON phase of the main pulsation finishes. To date, however, the generation mechanism of such an "over-darkening PsA" is still unclarified. In this study, we investigated the characteristics of the over-darkening PsA by using simultaneous observations of PsA with an electron multiplying charge coupled device all-sky camera in Sodankylä, Finland and the Arase satellite. During one of the conjunction events in Scandinavia on March 29, 2017, almost all the PsA pulses showed clear over-darkening characteristics. By analyzing the 2D all-sky images at the times of over-darkening we discovered that over-darkening areas appeared in the trailing edge of PsA patches and moved in tandem with the poleward propagating patches. It was also found that similar over-decreasing characteristics were not seen in the chorus data from the wave instruments onboard Arase located at the magnetospheric counterpart of PsA. These results indicate that the over-darkening PsA is not caused by a temporal variation of chorus at a fixed point, but is produced by a propagation of over-darkening area with PsA patches. That is, the over-darkening PsA is a result of compounding effects of spatial structure and recurrent propagation of PsA. The mechanism creating the dark area is still unknown, but the existence of over-darkening PsA suggests that the temporal variation of PsA is not always a perfect copy of the modulation of lower-band chorus waves in the magnetosphere. [ABSTRACT FROM AUTHOR]

This report describes electron beams observed at high latitudes in the magnetosphere by the Arase satellite. According to fine angular channel measurements, beam electrons are mainly flowing away from the Earth, and are well collimated to within a few degrees. A statistical study indicates that the beams are seen when Arase is located at Lm > ∼5, and more frequently as the magnetosphere becomes active. The field lines of the beam events are traced back to the typical auroral ovals. The statistical properties of the beams are consistent with the interpretation that ionospheric electrons are accelerated by a parallel electric field of an auroral potential structure and are streaming upward to the high latitude magnetosphere. Plain Language Summary: It is well accepted that discrete aurora is generated by precipitating electrons that are accelerated by an upward electric field. As a counterpart, a downward electric field exists in the vicinity of the upward electric field, accelerating ionospheric electrons upward to the magnetosphere. Such electron beams have been already reported by spacecraft observations in low altitudes and also in the magnetosphere. It is known that electron beams observed in the magnetosphere are collimated, but the pitch angle widths of the collimated beams have not been well resolved yet. In this report, we describe results of electron beam observations in the high latitude magnetosphere based on fine angular channel measurements of electrons by the Arase satellite. Key Points: Arase observes electron beams extremely collimated to within a few degrees in the high latitude magnetosphereElectron beams flow away from the Earth along the field lines connected to the auroral ovalsBeam electrons originate from a return current region of auroras in the ionosphere [ABSTRACT FROM AUTHOR]

We report the properties of the ionospheric exit point and characteristics of several types of very low frequency waves, including chorus and quasiperiodic emissions, based on a comprehensive dataset of simultaneous observations between ground and space. Whistler-mode waves were observed at Kannuslehto (L = 5.5, KAN), Finland, and in the inner magnetosphere by the Japanese Arase satellite. During the 2017--2018 winter campaign, we found 13 cases showing one-to-one correspondence of wave spectra between KAN and Arase. This is the first time that such a large number of conjugated events have been reported at once. The duration of the events ranged from a few minutes up to 3 h, with 90% of events detected in the afternoon sector. While the occurrence rate is higher during daytime, this can also be related to a majority of the detected waves being quasiperiodic emissions, a known dayside phenomenon. Arase was usually located within 30° of the equator, at L *4--5, and detected mostly waves propagating at oblique angles (≥20°). Frequently, the ionospheric magnetic footprint of Arase was located equatorwards (south) from KAN, often in the same geographical area. We investigated the probable location of the ionospheric exit point of the waves from the location of the footprint of Arase and the angle of arrival of waves detected at KAN. Using density measurements at Arase we discuss magnetospheric wave propagation; we find that, in most cases, waves were unducted in their propagation from the satellite to the ground. [ABSTRACT FROM AUTHOR]

Rectoanal intussusception (RAI) treated using laparoscopic ventral rectopexy (LVR) may give rise to rectorectal intussusception (RRI) during defecation postoperatively. However, only a few studies have analyzed the results of LVR using pelvic floor imaging, which is important when interpreting postoperative symptoms in patients with RAI. Thus, this study was designed to find the preoperative variables that may help predict the postoperative occurrence of RRI and to determine whether RRI may have negative effects on bowel symptoms after LVR for RAI. Consecutive patients treated between 2012 and 2017 were included. Defecatory function was evaluated using the Constipation Scoring System (CSS) and the Fecal Incontinence Severity Index (FISI). Defecography was performed before and 6 months after LVR. Of the 66 patients with RAI preoperatively, 34 had mixed obstructed defecation (OD) and fecal incontinence (FI), 18 had OD alone, and 12 had FI alone. Twelve months after surgery, a reduction of at least 50% was observed in the CSS score of 25 patients (52%) with OD and in the FISI of 37 incontinent patients (87%). Postoperatively, RAI was replaced with RRI in 21 and posterior RAI in 2 patients. These anatomical changes were found in patients who had a greater anorectal angle at rest preoperatively. However, the improvement in bowel symptoms was unrelated to the anatomical changes. Improvement in bowel symptoms after LVR for RAI was unrelated to the postoperative occurrence of RRI or posterior RAI, which were found in patients who had a vertical rectum at rest preoperatively. [ABSTRACT FROM AUTHOR]

We report the properties of the ionospheric exit point and characteristics of several types of very low frequency waves, including chorus and quasiperiodic emissions, based on a comprehensive dataset of simultaneous observations between ground and space. Whistler‐mode waves were observed at Kannuslehto (L = 5.5, KAN), Finland, and in the inner magnetosphere by the Japanese Arase satellite. During the 2017–2018 winter campaign, we found 13 cases showing one‐to‐one correspondence of wave spectra between KAN and Arase. This is the first time that such a large number of conjugated events have been reported at once. The duration of the events ranged from a few minutes up to 3 h, with 90% of events detected in the afternoon sector. While the occurrence rate is higher during daytime, this can also be related to a majority of the detected waves being quasiperiodic emissions, a known dayside phenomenon. Arase was usually located within 30° of the equator, at L ∼4–5, and detected mostly waves propagating at oblique angles (≥20°). Frequently, the ionospheric magnetic footprint of Arase was located equatorwards (south) from KAN, often in the same geographical area. We investigated the probable location of the ionospheric exit point of the waves from the location of the footprint of Arase and the angle of arrival of waves detected at KAN. Using density measurements at Arase we discuss magnetospheric wave propagation; we find that, in most cases, waves were unducted in their propagation from the satellite to the ground.Key Points: First time such a large number (13) of space‐ground conjugated events of magnetospheric whistler‐mode ELF/VLF waves is reportedIonospheric exit point of the waves is usually located at least ∼250 km equatorwards (south) of ground station in Finland at L ∼5.5All conjugated events but one were observed on the afternoon side of the magnetosphere [ABSTRACT FROM AUTHOR]

Electrostatic electron cyclotron harmonic (ECH) waves are generally excited in the magnetic equator region, in the sector from nightside to dayside during geomagnetically active conditions, and cause the pitch angle scattering by cyclotron resonance. The scattered electrons precipitate into the Earth's atmosphere and cause auroral emission. However, there is no observational evidence that ECH waves actually scatter electrons into the loss cone in the magnetosphere. In this study, from simultaneous wave and particle observation data obtained by the Arase satellite equipped with a high‐pitch angular resolution electron analyzer, we present evidence that the ECH wave intensity near the magnetic equator is correlated with an electron flux inside the loss cone with an energy of about 5 keV. The simulation suggests that this electron flux contributes to the auroral emission at 557.7 nm with an intensity of about 200 R. Plain Language Summary: Wave‐particle interaction via electrostatic electron cyclotron harmonic (ECH) waves is a promising generation mechanism for precipitating electrons into Earth's atmosphere and producing diffuse auroras. However, there is no observational evidence that ECH waves scatter electrons to cause auroral emissions. In this study, based on observation data obtained by the Arase satellite equipped with a high‐angular resolution electron analyzer, we identified an event during which the ECH wave intensity near the magnetic equator was correlated with the electron flux that precipitated into the Earth's atmosphere. Our simulation suggests that this electron flux contributes to visible oxygen green‐line auroral emission. Key Points: We found an event that electron cyclotron harmonic wave intensity correlated with electron flux in a loss cone with ~5 keV energyThe pitch‐angle diffusion coefficient of 5 keV is larger than those of other energies when the electron temperature is 8 eV and the wave normal angle is 88.5°The electron flux correlated with the ECH wave intensity can cause 557.7 nm auroral emission with ~200 R intensity [ABSTRACT FROM AUTHOR]

We have developed the automatic detection scheme for upper hybrid resonance (UHR) frequency using a convolutional neural network (CNN) from the electric field spectra obtained by the plasma wave experiment (PWE) aboard Arase. In this paper, we investigate the practical capability of this scheme in terms of actual scientific use case. We find that the average error rate is below 7.8% when the wave frequency is above 30 kHz and the wave spectral intensity is less than 10−5 mV 2/m2/Hz. About 91% of the data obtained by the high‐frequency analyzer (HFA) aboard the Arase satellite satisfies these conditions. To improve the accuracy of the determined UHR frequencies in a wide frequency range, we used another receiver, the onboard frequency analyzer (OFA), which enables us to detect low‐frequency UHR emissions. We confirmed that the averaged error rate derived by the OFA spectra becomes better than that derived from the HFA spectra in a frequency range below 20 kHz. We report the performance of the UHR frequency determination under the different geomagnetic conditions. We find that the UHR frequency can be determined with good accuracy using the CNN from the frequency‐time diagram both during geomagnetically quiet and disturbed conditions. We conclude that the CNN‐based UHR frequency determination is a reliable method to derive the electron density along the satellite orbit through observations of UHR frequencies, and this method contributes to studies on dynamics of the plasmasphere. Plain Language Summary: Determining the upper hybrid resonance (UHR) frequency is the most popular way to determine the quantitative electron density in space. The high‐frequency analyzer (HFA) and onboard frequency analyzer (OFA) aboard the Arase satellite measure electric field spectra at high‐ and low‐frequency ranges. The nominal time resolutions of the HFA and OFA spectra are 8 and 1 s, respectively. Determining the UHR frequency by conventional visual inspection requires huge resources for researchers; therefore, some automatic determination methods have been proposed in recent years. In this study, we evaluate the accuracy of UHR frequency determination by convolutional neural networks (CNN). We find that the averaged error rate of the automatically determined UHR frequency is less than 7.8% for the most events (91% of the data set), and we conclude that the CNN‐based UHR frequency determination is the reliable method to estimate the electron density along the satellite orbit. Key Points: We investigated the practical capability of the CNN‐based UHR frequency detection and found that the error is below 7.8% for most eventsWe successfully improved the accuracy of UHR frequency determination in a low‐frequency range by combining the OFA spectraWe confirmed that the UHR emissions in plasmasphere can be determined with good accuracy both during quiet and disturbance periods [ABSTRACT FROM AUTHOR]

Recent availability of a considerable amount of satellite and ground-based data has allowed us to analyze rare conjugated events where extremely low and very low frequency waves from the same source region are observed in different locations. Here, we report a quasiperiodic (QP) emission, showing one-to-one correspondence, observed by three satellites in space (Arase and the Van Allen Probes) and a ground station. The main event was on 29 November 2018 from 12:06 to 13:08 UT during geomagnetically quiet times. Using the position of the satellites we estimated the spatial extent of the area where the one-to-one correspondence is observed. We found this to be up to 1.21 Earth's radii by 2.26 hr MLT, in radial and longitudinal directions, respectively. Using simple ray tracing calculations, we discuss the probable source location of these waves. At ~12:20 UT, changes in the frequency sweep rate of the QP elements are observed at all locations associated with magnetic disturbances. We also discuss temporal changes of the spectral shape of QP observed simultaneously in space and on the ground, suggesting the changes are related to properties of the source mechanisms of the waves. This could be linked to two separate sources or a larger source region with different source intensities (i.e., electron flux). At frequencies below the low hybrid resonance, waves can experience attenuation and/or reflection in the magnetosphere. This could explain the sudden end of the observations at the spacecraft, which are moving away from the area where waves can propagate. [ABSTRACT FROM AUTHOR]

The effect of microbe combination with TiO2 on photocatalytic degradation of Rhodamine B was investigated. The self-assembled TiO2 spheres were synthesized by the solvothermal method for preparation of hybrid TiO2/Paint Sludge Extracted Microbe (PSEM) composite. The structure of as-synthesized TiO2 was analyzed by the powder X-ray diffraction method, and phase purity was verified with Raman analysis. Spherical morphology and self-assembled nature of TiO2 was confirmed by field emission scanning electron microscopy (FE-SEM). PSEM extracted from Paint sludge and was used to synthesize TiO2/PSEM hybrid composite. The dispersion of TiO2 self-assembled spheres on the walls of PSEM was confirmed with FE-SEM micrographs. TiO2/PSEM composite (94%) showed enhanced photocatalytic dye degradation when compared with as-synthesized TiO2 (85%). [ABSTRACT FROM AUTHOR]

We have succeed in growing single crystals of EuCu 5 and EuAu 5 with the hexagonal structure by the Bridgman method. Both compounds are known to be ferromagnets with Curie temperatures T C = 57 and 13 K, respectively, and the Eu-4f magnetic moments of EuCu 5 are known to orient along the hexagonal c-axis or the [0001] direction by the Mössbauer experiment. The magnetisations at 2 K in EuCu 5 and EuAu 5 in the present experiment saturate at an extremely low field of 2 kOe for H ∥ [ 0001 ] , with a Eu 2 + -moment of 7 μ B / E u . On the other hand, the hard-axis magnetisations for H ⊥ [0001] saturate at a high field of 40 kOe. It is also found from the electrical resistivty measurement that the electrical resistivities along the current J ∥ [0001] in EuCu 5 and EuAu 5 are about 10 μ Ω ⋅ c m at room temperature, which are compared with the resistivities of ρ = 30–40 μ Ω ⋅ c m for J ⊥ [0001]. The quasi-one dimensional conductivities are also characteristic, which were clarified from the de Haas-van Alphen (dHvA) experiment and FLAPW energy band calculation for EuAu 5 , revealing the existence of a large plate-like Fermi surface. [ABSTRACT FROM AUTHOR]

Background: Oesophageal squamous cell carcinoma is an aggressive disease owing to early and widespread lymph node metastases. Multimodal therapy and radical surgery may improve prognosis. Few studies have investigated the efficacy of radical lymph node and thoracic duct resection. Methods: Patients with oesophageal squamous cell carcinoma who underwent transthoracic minimally invasive oesophagectomy (TMIE) for cancer at Keio University Hospital between January 2004 and December 2016 were selected. Between 2004 and 2008, TMIE was performed in the lateral decubitus position without thoracic duct resection (standard TMIE). From 2009 onwards, TMIE with extended lymph node and thoracic duct resection was introduced (extended TMIE). Demographics, co‐morbidity, number of retrieved lymph nodes, pathology, postoperative complications and recurrence‐free survival (RFS) were compared between groups. Results: Forty‐four patients underwent standard TMIE and 191 extended TMIE. There were no significant differences in clinical and pathological tumour stage or postoperative complications. The extended‐TMIE group had more lymph nodes removed at nodal stations 106recL and 112. Among patients with cT1 N0 disease, RFS was better in the extended‐TMIE group (P < 0·001), whereas there was no difference in RFS between groups in patients with advanced disease. Conclusion: Extended TMIE including thoracic duct resection increased the number of lymph nodes retrieved and was associated with improved survival in patients with cT1 N0 oesophageal squamous cell carcinoma. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Drastic variations of radiation‐belt/ring current electrons are the result of competing processes of acceleration, transport, and loss. For subrelativistic energetic electrons (10–100 keV), one of the promising loss mechanisms is precipitation into the atmosphere due to pitch angle scattering by whistler mode chorus waves. The efficiency of the scattering has yet to be quantified by direct observations, however. Using in situ measurements by the ERG (Arase) spacecraft in the midnight‐to‐dawn sector at and around the magnetic equator, we demonstrate that the full filling of energetic electron loss cones occurs commonly, associated with typical‐amplitude (greater than 50 pT) chorus waves. The spatial distribution of the loss cone filling indicates that the efficient scattering is limited to |MLAT|< 10°. Plain Language Summary: Drastic variations of high‐energy (10–100 keV) electrons in the Earth's magnetosphere are the result of competing processes of acceleration, transport, and loss. In order to understand their dynamics, therefore, it is important to quantify each process. One of the promising loss mechanisms is precipitation into the atmosphere due to the interaction with electromagnetic waves called "chorus waves." However, the precipitation rate has yet to be quantified by direct observations in the interaction region. Using in situ measurements by the ERG (Arase) spacecraft in the magnetosphere, we demonstrate that the full throttle precipitation occurs commonly, associated with typical‐amplitude (greater than 50 pT) chorus waves. The observed spatial distribution indicates that the efficient interaction is confined at/around the magnetic equator. Key Points: Spatial distribution of medium‐energy loss cone electrons in the low‐latitude magnetosphere is shown for the first timeThe strong diffusion is common when chorus waves are activeStrong scattering occurs only at the near‐equatorial region (|magnetic latitude|< 10°) in the midnight‐to‐dawn sector [ABSTRACT FROM AUTHOR]

We present the first and direct comparison between magnetospheric plasma waves and polar mesosphere winter echoes (PMWE) simultaneously observed by the conjugate observation with Arase satellite and high‐power atmospheric radars in both hemispheres, namely, the Program of the Antarctic Syowa Mesosphere, Stratosphere, and Troposphere/Incoherent Scatter Radar at Syowa Station (SYO; −69.00°S, 39.58°E), Antarctica, and the Middle Atmosphere Alomar Radar System at Andøya (AND; 69.30°N, 16.04°E), Norway. The PMWE were observed during 03–07 UT on 21 March 2017, just after the arrival of corotating interaction region in front of high‐speed solar wind stream. An isolated substorm occurred at 04 UT during this interval. Electromagnetic ion cyclotron (EMIC) waves and whistler mode chorus waves were simultaneously observed near the magnetic equator and showed similar temporal variations to that of the PMWE. These results indicate that chorus waves as well as EMIC waves are drivers of precipitation of energetic electrons, including relativistic electrons, which make PMWE detectable at 55‐ to 80‐km altitude. Cosmic noise absorption measured with a 38.2‐MHz imaging riometer and low‐altitude echoes at 55–70 km measured with an medium‐frequency radar at SYO also support the relativistic electron precipitation. We suggest a possible scenario in which the various phenomena observed in near‐Earth space, such as magnetospheric plasma waves (EMIC waves and chorus waves), pulsating auroras, cosmic noise absorption, and PMWE, can be explained by the interaction between the high‐speed solar wind containing corotating interaction regions and the magnetosphere. Key Points: EMIC waves and chorus waves in the magnetosphere and PMWE in the mesosphere were observed simultaneously by the conjugate observationPMWE were detected by the PANSY and MAARSY radars in both Northern and Southern Hemispheres during the equinox periodThe temporal variation of the chorus wave power was quite similar to those of PMWE powers observed in both hemispheres [ABSTRACT FROM AUTHOR]

Vitreous silicon oxide (v-SiO2) shows anomalous phonon properties such as the positive temperature coefficient of velocity (TCV). Variation of the Si–O–Si bond angle between SiO4 tetrahedrons has been recognized to be the key, but the origin of TCV still remains unclear. In this study, we controlled the bond angle by doping nitrogen and measured TCV of vitreous silicon oxynitride thin films with various nitrogen concentrations using picosecond ultrasonics. TCV significantly decreases by adding a small amount of nitrogen, and it shows positive to negative values as the nitrogen concentration increases. We evaluated the bond-angle change by Fourier-transform infrared spectroscopy, which decreases with the increase in the nitrogen content. We also find that the temperature rise in nondoped v-SiO2 decreases the bond angle, leading to an increase in the sound velocity. We then reveal theoretically that the bond-angle change dominates the origin of the positive TCV. This study indicates the existence of a zero-TCV single material, and we discover that the specific content of v-SiO1.71N0.19 achieves this. [ABSTRACT FROM AUTHOR]

Equatorial noise (EN) emissions are observed inside and outside the plasmapause. EN emissions are referred to as magnetosonic mode waves. Using data from Van Allen Probes and Arase, we found conversion from EN emissions to electromagnetic ion cyclotron (EMIC) waves in the plasmasphere and in the topside ionosphere. A low‐frequency part of EN emissions becomes EMIC waves through branch splitting of EN emissions, and the mode conversion from EN to EMIC waves occurs around the frequency of M/Q = 2 (deuteron and/or alpha particles) cyclotron frequency. These processes result in plasmaspheric EMIC waves. We investigated the ion composition ratio by characteristic frequencies of EN emissions and EMIC waves and obtained ion composition ratios. We found that the maximum composition ratio of M/Q = 2 ions is ~10% below 3,000 km. The quantitative estimation of the ion composition will contribute to improving the plasma model of the deep plasmasphere and the topside ionosphere. Plain Language Summary: Equatorial noise (EN) emissions are whistler mode waves. Using Van Allen Probe and Arase (ERG) plasma wave data, we found that EN emissions propagate toward the Earth and are converted to electromagnetic ion cyclotron (EMIC) waves in the deep plasmasphere and the topside ionosphere. We suggest that minor ions with a mass per charge (M/Q) = 2, that is, deuteron or alpha particles, play an important role in this process. The processes reported here are a new generation process of plasmaspheric EMIC waves. Moreover, we determined the ion composition ratio using characteristics of wave dispersion. We derived the altitude profile of the ion composition ratio and identified the maximum ratio of M/Q = 2 ions of about 10% in the deep plasmasphere. Key Points: The first measurements of the conversion from equatorial noise to EMIC waves are presentedExistence of M/Q = 2 ions (deuteron or alpha particle) in the deep plasmasphere is essential to cause the conversionThe ion composition ratio is quantitatively estimated in the deep plasmasphere using characteristics of the wave dispersion [ABSTRACT FROM AUTHOR]

The temporal modulations of magnetospheric chorus waves are one of the candidates for explaining quasiperiodic precipitation of energetic electrons causing pulsating aurora (PsA). To confirm fully the direct association between PsA and chorus, an extended interval of PsA (~1 hr) simultaneously observed by the Arase satellite and a ground‐based all‐sky imager in Apatity, Kola Peninsula, Russia was examined. In particular, a region of high correlation between PsA and chorus was continuously tracked within the field of view of the all‐sky imager. The result showed that the high‐correlation region and the modeled footprint of Arase moved in tandem. This strongly implies that the chorus and PsA electrons originated from the same local interaction region. In addition, the location of the high‐correlation region showed sudden jumps, which were probably associated with the motion of the satellite through discrete spatial structures of plasma in the region of wave‐particle interaction. Plain Language Summary: Pulsating aurora (PsA), which consists of luminous patches/arcs blinking with various periodicities ranging from a few to a few tens of seconds, is known to occur very frequently during the recovery phase of auroral substorms. It has been suggested that the luminosity variation of PsA is controlled by natural electromagnetic waves in space, which are called chorus waves. There have been several studies that demonstrated one‐to‐one correspondence between the temporal variations of PsA and chorus waves. However, it is still unclear how long such a good correlation between PsA and chorus is preserved. In this study, an extended interval of PsA (~1 hr) simultaneously observed by a newly launched magnetospheric satellite, Arase, and a ground‐based high‐speed all‐sky imager in Apatity, Kola Peninsula, Russia was investigated. As a result, not only was the correspondence between PsA and chorus verified but also the motion of the high‐correlation region (correlation coefficient > 0.5) was successfully tracked in a continuous manner. The obtained long‐lasting reasonable correlation proves that the chorus waves control the luminosity variation of PsA. In addition, the region of high correlation between PsA and chorus showed sudden jumps, which could be caused by the motion or variation of the fine‐scale structure of the wave‐particle interaction region in space. Key Points: Observation of the Arase satellite with an all‐sky imager revealed a long‐lasting correlation between pulsating aurora and chorus wavesThe high‐correlation region sometimes changed abruptly, which could have resulted from the discrete spatial structure of plasmaThe cross‐correlation analysis can be used for monitoring the local link between the ionosphere and magnetosphere [ABSTRACT FROM AUTHOR]

Presents a study to compare effects of electron and proton irradiation on n+-p-p+ silicon diodes. Methodology used to conduct study; Indication of findings; Discussion on results.

Studies n+\p\p+ silicon diodes irradiated with fluences of 1 MeV electrons. Device failure due to majority carrier removal; Measurements of capacitance-voltage; Relationship of the carrier concentration of the base of the device and the radiation fluence; Comparison with the defect spectra; Role of other trap levels in the carrier removal process.

Abstract: Aim: To report a case of reparative bone‐like tissue formation in the tooth of a patient with systemic sclerosis. Summary: A 58‐year‐old Japanese female patient with systemic sclerosis was referred because of tooth fracture. Cone beam computerized tomography (CBCT) revealed multiple root resorption and the unclear transition from alveolar bone to root profile. A sample from a fractured tooth was analysed histologically. Haematoxylin and eosin‐stained sections revealed the irregular replacement of pulp and dentine by bone‐like tissue. Calcinosis was noted in various parts of the body and a histological analysis identified it as dystrophic calcification on sclerosed fibrous connective tissue. Bite force and the occlusal area were markedly weaker than the means for female of the same age. Key learning points: CBCT may be more useful than dental radiography for diagnosing multiple root resorption in systemic sclerosis patients. When systemic sclerosis patients have calcinosis, their root status must be examined carefully. When root resorption is present in systemic sclerosis patients, reparative bone‐like tissue formation in teeth needs to be taken into account prior to the initiation of dental treatment. [ABSTRACT FROM AUTHOR]