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Recently, integrated geophysical‐geological surveys in the Nankai subduction zone in Japan have revealed that slow earthquakes repeatedly occur beneath the outer wedge of the forearc. During December 2020 to February 2021, clustered slow earthquakes propagated around the frontal thrust of the accretionary wedge. The frontal thrust ramps up from the basal décollement and slips over trench‐filling sediment along the landward edge of the Nankai trough floor. Here, the Paleo‐Zenisu ridge has been subducted beneath the inner‐outer slope border. In addition, ocean floor topography and geologic structure revealed by seismic reflection surveys completed before 2022 document that the basement of the Philippine Sea Plate beneath the frontal thrust has a seamount and a horst‐like basement high. The northern edge of the basement high is located at the ramp‐up position of the frontal thrust. The 2020–2021 clustered slow earthquakes started at the Paleo‐Zenisu ridge and propagated to the topographic highs beneath the deformation front. Considering that the relative plate convergence between the upper Amurian Plate of the Nankai forearc and the subducting Philippine Sea Plate is ∼6.0 cm/year, the basement high at the deformation front has uplifted the frontal crest of the wedge at an average rate of 2.7–5.7 mm/year for several tens to hundred thousand years. These rates are among some of the highest rock uplift rates measured in the world. The slow earthquakes in the off‐Kumano Nankai Trough in 2020–2021 are a snapshot of a "living" Nankai frontal thrust during the megathrust interseismic period. Plain Language Summary: Slow earthquakes family: slow slips, very low frequency earthquakes, and tremors are significant events for understanding the interseismic dynamics between large earthquakes along the convergent plate boundary in the ocean. Slow earthquakes took place during December 2020 to February 2021 in the Nankai Trough in Japan and propagated along the frontal edge of the upper plate. Seismic reflection surveys revealed that seamount‐like and horst‐like basement highs exist beneath the front, collide with the upper plate, and uplift trench filling sediments by a ramp thrust. Even the incipient plate boundary of the décollement is initiated within the sediments beneath the Nankai Trough. Such a deformation feature around the front is a source candidate for the slow earthquakes. The uplift rate of the frontal crest of the upper plate presents the same order of a few to several mm/year as that of the foreland of the Himalayan Mountain belt. The slow earthquakes in the off‐Kumano Nankai Trough in 2020–2021 appear the first snapshot of a "living" Nankai frontal thrust during inter‐large seismic period. Key Points: Between 2020 and 2021, slow earthquakes propagated around the frontal thrust of the accretionary wedge in the Nankai Trough off KumanoSeamount and horst‐like basement highs beneath the frontal thrust cause uplift and are associated with the slow earthquake eventsThe average uplift rate of the frontal crest is 2.7–5.7 mm/year, approximately the same order as that of the Himalayan foreland [ABSTRACT FROM AUTHOR]

Characterization, understanding, and prediction of the Martian radio environment are of increasing importance to the forthcoming human exploration of Mars. Here we investigate 3–5 MHz radio absorption in the nightside ionosphere of Mars caused by enhanced ionization at <100 km altitudes during solar energetic particle (SEP) events. We conduct a quantitative analysis of radio absorption and SEP flux data that have been accumulated by two spacecraft currently orbiting Mars, thereby demonstrating that radio absorption is clearly correlated with SEP fluxes. A comparison of the observations with radio absorption properties predicted by a numerical model indicates that the relative temporal changes, radio frequency dependence, and SEP energy dependence of the observed radio absorption are in agreement with the model prediction. Meanwhile, the model systematically overestimates the radio absorption in the ionosphere by a factor of 3.7. We explore several sources of uncertainty, including the electron‐neutral collision frequency, absolute sensitivity of the SEP instrument, and limited transport of SEPs to the atmosphere, but the ultimate cause of the systematic discrepancy between the measured and modeled radio absorption is yet to be identified. Further efforts should be put into the development of a comprehensive and observationally validated model of radio absorption in the Martian ionosphere to assist the future crew and spacecraft activities on the surface of Mars. Plain Language Summary: Radio waves are widely used for communication, positioning, and navigation in our society. As human exploration of Mars progresses in the coming decades, radio technology will be in use for crew and spacecraft activities on the surface of Mars. On Earth, high‐frequency radio communication is sometimes disrupted due to enhanced radio absorption in the lower ionosphere arising from solar flares. The ionosphere of Mars also causes strong radio absorption during space weather events as observed in the nightside ionosphere during solar energetic particle (SEP) precipitation. To assess the effects of ionospheric absorption on radio communication at Mars, we need to develop a reliable numerical model that is validated against observations. We initiate this effort by comparing observations with predictions from a state‐of‐the‐art numerical model. The model successfully reproduces important aspects of the observed radio absorption during SEP events, namely relative temporal changes, radio frequency dependence, and SEP energy dependence. However, the modeled and observed absorption levels systematically differ by a factor of 3.7, reasons for which have not been fully understood. Further research is required to improve and validate the model if we are to characterize the radio communication environment prior to the future arrival of humans to Mars. Key Points: Observations indicate a clear correlation between solar energetic particle fluxes and radio absorption in the nightside ionosphere of MarsThe observed properties of radio absorption are well reproduced by a numerical model except for a factor of 3.7 systematic discrepancyFurther model development and validation will pave the way for accurate prediction of the radio environment on the Martian surface [ABSTRACT FROM AUTHOR]

To achieve high-thrust-density operation, we propose electrostatic–magnetic hybrid ion acceleration in which the empirical thrust density limit of the electrostatic acceleration is surpassed without violent plasma oscillation by combing the collisional momentum transfer mechanism, which is the ion acceleration mechanism of the electromagnetic acceleration. To achieve hybrid ion acceleration, we experimentally obtained two design criteria: one near anode propellant injection and another at the on-axis hollow cathode location. The thrust characteristics of three thrusters composed of a slowly diverging magnetic field between an on-axis hollow cathode and a coaxially set ring anode were examined. By injecting xenon propellant along the anode inner surface, the electron impact ionization process was enhanced, and generated ions are electrostatically accelerated through the radial-inward potential gradient perpendicular to the axial magnetic lines of force. The hybrid ion acceleration characteristics were obtained only if these two criteria were satisfied and the obtained thrust was consistent with the thrust formula derived for steady-state, quasi-neutral plasma flows. In addition to the criteria, strengthening the magnetic field and enhancing the propellant mass flux were effective for improving thrust density without deteriorating thrust efficiency. Among the experimental conditions in this study, the maximum thrust density was 70 N/m2 with an anode specific impulse of 1200 s, which cannot be achieved in a purely electrostatic thruster with thrust density 6.3 times than that of a typical Hall thruster. [ABSTRACT FROM AUTHOR]

A gamma‐ray glow, a minute‐lasting burst of high‐energy photons from a thundercloud, was detected by ground‐based apparatus at Kanazawa University, Japan, in a winter thunderstorm on 18 December 2018. The gamma‐ray glow was quenched by a lightning flash within a brief time window of 40 ms. The lightning flash produced several low‐frequency (LF) E‐change pulses that were temporally coincident with the termination of the gamma‐ray glow, and that were located within 0.5 km from the observation site by the Fast Antenna Lightning Mapping Array. The LF pulses had the same polarity as a positive cloud‐to‐ground current and a normal‐polarity in‐cloud current. Since this polarity is against the upward electric field for producing the gamma‐ray glow (accelerating electrons to the ground), we infer that the glow was terminated by a normal‐polarity in‐cloud discharge activity between a middle negative layer and an upper positive layer. Plain Language Summary: Strong electric fields inside thunderclouds may accelerate electrons to relativistic energy, and cause a burst of high‐energy photons called gamma‐ray glow. Gamma‐ray glows are sometimes terminated with a lightning flash as it discharges electric fields responsible for electron acceleration. In this study, we observed the termination of a gamma‐ray glow with a detailed lightning mapping observation in the radio‐frequency band. An in‐cloud lightning flash between two charge layers inside a thundercloud reduced an electric field that accelerated electrons. Radio‐frequency observations of glow termination are a powerful tool to investigate the charge structure associated with electron acceleration. Key Points: A gamma‐ray glow was terminated by a lightning flash within a brief time window of 40 msPositive‐polarity low‐frequency pulses were located within 0.5 km of the detection siteThe glow was ceased by a normal‐polarity in‐cloud discharge activity between a middle negative layer and an upper positive layer [ABSTRACT FROM AUTHOR]

Hybrid quantum systems in the ultrastrong, and even more in the deep-strong, coupling regimes can exhibit exotic physical phenomena and promise new applications in quantum technologies. In these nonperturbative regimes, a qubit–resonator system has an entangled quantum vacuum with a nonzero average photon number in the resonator, where the photons are virtual and cannot be directly detected. The vacuum field, however, is able to induce the symmetry breaking of a dispersively coupled probe qubit. We experimentally observe the parity symmetry breaking of an ancillary Xmon artificial atom induced by the field of a lumped-element superconducting resonator deep-strongly coupled with a flux qubit. This result opens a way to experimentally explore the novel quantum-vacuum effects emerging in the deep-strong coupling regime. Hybrid quantum systems, such as superconducting qubits interacting with microwave photons in resonators, offer a rich platform for exploring fundamental physics. Wang et al. observe parity symmetry breaking in a probe qubit dispersively coupled to a resonator in the deep-strong coupling regime. [ABSTRACT FROM AUTHOR]

Gamma‐ray glows are observational evidence of relativistic electron acceleration due to the electric field in thunderclouds. However, it is yet to be understood whether such relativistic electrons contribute to the initiation of lightning discharges. To tackle this question, we started the citizen science "Thundercloud Project," where we map radiation measurements of glows from winter thunderclouds along Japan's sea coast area. We developed and deployed 58 compact gamma‐ray monitors at the end of 2021. On 30 December 2021, five monitors simultaneously detected a glow with its radiation distribution horizontally extending for 2 km. The glow terminated coinciding with a lightning flash at 04:08:34 JST, which was recorded by the two radio‐band lightning mapping systems, FALMA and DALMA. The initial discharges during the preliminary breakdown started above the glow, that is, in vicinity of the electron acceleration site. This result provides one example of possible connections between electron acceleration and lightning initiation. Plain Language Summary: Thunderstorms are natural particle accelerators. The strong electric field inside thunderclouds accelerates relativistic electrons, which emit gamma rays via interaction with the atmosphere. High‐energy photons generated in this process have been observed as radiation enhancements called gamma‐ray glows. Winter thunderclouds along the sea of Japan are an ideal target for monitoring glows because their altitudes are usually sufficiently low for the generated gamma‐ray photons to reach the ground. We started a new citizen science "Thundercloud Project" in this area, where we distributed radiation detectors to citizen supporters to observe glows and to reveal their relationship with the aerological condition and lightning discharges. On 30 December 2021, five of those sensors detected a glow from a single thundercloud. Two of them recorded a sudden termination of the glow coinciding with a lightning flash, which was monitored by our two radio mapping systems of FALMA and DALMA. The initial discharges of the flash started at a location about 1.6 km above the glow region with an unusually fast downward progression. This paper is the first report of our citizen science project. We discuss the possibility that accelerated electrons contribute to the initiation of lightning discharges. Key Points: We started the citizen science "Thundercloud Project," a multi‐point observation campaign of gamma‐ray glows from thunderstormsOn 30 December 2021, five radiation monitors detected a 2‐km‐long size gamma‐ray glow, which suddenly terminated with a lightning flashTwo radio mapping systems of lightning identified the initiation of the discharges, which started at a location above the glow region [ABSTRACT FROM AUTHOR]

Plasma β dependence of ion temperature gradient (ITG) driven turbulence is investigated using gyrokinetic simulations, where β is the normalized pressure. In our β scan, self-consistent magnetohydrodynamic (MHD) equilibrium state is numerically calculated for each value of β. It is found that the influence of the Shafranov shift cancels out the electromagnetic stabilizing effect on the ITG mode, and the growth rate of the ITG mode is accordingly unchanged as β increases. As a result, the turbulent energy transport does not decrease with β as suggested by the s − α model (Ishizawa et al 2019 Phys. Rev. Lett. 123 025003). A significant difference from the s − α model is the increase of the energy transport with β. It is also found that the critical onset β value for the kinetic ballooning mode is significantly increased by the influence of the Shafranov shift. The cancellation of the electromagnetic stabilization by the Shafranov shift is explained by the decrease of magnetic drift frequency in the dispersion relation of electromagnetic ITG modes obtained by using a fluid approximation. [ABSTRACT FROM AUTHOR]

Fe 2 TiSi has been expected to be one of the high-performance thermoelectric full-Heusler alloys. Here, we experimentally clarify the room-temperature Seebeck coefficient (S) and thermal conductivity (κ) for the Fe 2 TiSi films. Using a molecular beam epitaxy technique, we demonstrate the high degree of L 2 1 -ordering and the homogeneous single-phase structure in the Fe 2 TiSi films. We find that the intrinsic conduction carriers of the Fe 2 TiSi films are holes and impurity-induced carrier scattering is indicated, derived from weak magnetic moments due to the presence of D 0 3 -type (Fe ⇔ Ti) structural disorder in the Fe 2 TiSi film. From reliable measurements for thin films, the values of S and κ are estimated to be 101 μ V/K and 5.6 W/(m K), respectively, at room temperature. This study will open a new way for full-Heusler alloy thermoelectric materials other than those in Fe 2 VAl systems. [ABSTRACT FROM AUTHOR]

Underwater disturbances are the largest error source in Global Navigation Satellite System - Acoustic ranging combination technique (GNSS-A) seafloor geodetic observation. In particular, the gradient of sound speed structure (SSS) directly affects the horizontal accuracy and needs to be examined. Previous studies have not investigated its temporal change component. In this paper, we verified the assumption that the underwater gradient structure does not change significantly during GNSS-A observation for several hours through applying a modified version of an analysis software called GARPOS to actual data of SGO-A (provided by Japan Coast Guard). Obtained results suggested that this assumption holds at many observation data, and the positioning accuracy becomes better. Some non-improved observation epochs were speculated to be accompanied by structure changes for which this assumption was not valid. It is suggested that the SSS change during observation will be an important research topic in GNSS-A. [ABSTRACT FROM AUTHOR]

The Paα line (1875.13 nm) in the near-infrared (NIR) region was evaluated to apply Stark broadening of the line spectrum to the electron density measurement of the small-pellet ablation cloud in Heliotron J, a medium-sized helical-axis heliotron device. Paα is three-to-four times broader than the visible Hβ line (486.13 nm) for the same electron density. Using a portable NIR spectrometer, preliminary proof-of-concept experiments determined the marginal density, below which the broadening was undetectable. The lower detection density limit can be decreased using a narrower entrance slit or a denser grating. [ABSTRACT FROM AUTHOR]

Electrical-field-induced insulator-to-metal (I-to-M) transition of samarium monosulfides was investigated systematically. Experiment results demonstrate that Sm0.9Ca0.1S undergoes the I-to-M transition when in a small electric field of 250 V/cm at liquid-nitrogen temperatures. However, simultaneous measurement of I–V characteristics and strain did not detect the electrical-field-induced strain expected from the large volume contraction originating from the valence transition of Sm. Mid-infrared to visible region reflectivity spectroscopy in the field-induced transition revealed no spectral change other than the temperature change attributable to Joule heat. This lack of change contrasts to the large-scale spectrum changes, such as a sharp rise in reflectivity, which appear in the metallic phase induced by pressure or element substitution. The detailed analysis of the field-induced strain suggests that filamentary metallic paths are formed during the breakdown process, just as they are for strongly correlated insulators. [ABSTRACT FROM AUTHOR]

The causes for forearc basin and megathrust rupture zone segmentation are controversial. The Nankai forearc, Japan, is separated into five domains based on topography: Enshu, Kumano, Muroto, Tosa, and Hyuga. The boundaries of these domains correspond to the rupture limits of large earthquakes. We examined the geologic structure of the boundary region between the Kumano and Muroto domains off the Kii Peninsula using multichannel seismic reflection data to evaluate the role of upper plate composition in controlling segmentation. The results suggest that thick cover sediments and underlying accretionary prism are obliquely thrust landward over the igneous basement complex rock in the region of offshore of Cape Shionomisaki and separate the forearc basin. The igneous basement complex rocks directly overlying the plate interface in the hypocentral regions of 1944 Tonankai and 1946 Nankai earthquakes. The 1944 earthquake originated at the base of the complex, and the rupture extent slipped past its basement boundary, whereas the 1946 event nucleated at the updip boundary of the basement complex. The dense igneous rocks might have worked as a heavily loaded barrier on the seismogenic megathrust and separated the rupture area of both the earthquakes. Upper plate geology may be an important factor in controlling seismogenesis in the Nankai Trough and may serve as an example for understanding the controls on megathrust slip in other subduction zones. Plain Language Summary: The Nankai Trough, Japan is the place where quakes nucleate in the margin and tsunamis repeatedly devastated circum‐Pacific societies. When, where, why, and how the quakes were started in the trench is a central scientific question but unsolved. The historical records of earthquakes suggest that the rupture started around Cape Shionomisaki of the Kii Peninsula, where there is also a topographic segment boundary of the ∼2,000 m deep basin in the middle continental slope. Our research of the geologic structure beneath the earthquake epicenters indicates a dense and hard rock mass situated upon the hypocenters of 1944, and 1946 megaquakes off Cape Shionomisaki. The rock mass might have worked as a heavy load and barrier on the low angle dipping plate boundary fault when the fault slipped the large rupture was propagated in the Nankai Trough. Key Points: The Nankai forearc basin is separated off the Kii Peninsula owing to the existence of middle Miocene igneous basement in the upper plateThe rupture areas of the 1944 Tonankai, 1946 Nankai, and 2016 off‐Mie earthquakes appear to be controlled by the igneous basementThe shallow distribution of very low‐frequency earthquakes and tremors are related to the geological heterogeneity of the upper plate [ABSTRACT FROM AUTHOR]

Based on the Riemann problem in compressible fluid dynamics, if the head of an unsteady jet acts as a physical piston for air compression, a higher-pressure field than that of the kinetic pressure from a steady jet can be generated. In this study, the pressure characteristics of this air compression method, referred to as "remote in-tube air compression," were evaluated. The generated unsteady jet exhibited a high-pressure region in its central part that effectively acted as a physical piston (piston effect). Depending on the distance between the unsteady jet generator and a cylindrical test section, the overpressure inside the test section reached the maximum value when the cross section of the jet head and the test section were matched. This matching condition was consistent with the in-tube pressure characteristics, thereby yielding an effective method for the remote generation of a high-pressure region using a simple device. [ABSTRACT FROM AUTHOR]

Summary: The baseline sagittal vertical axis (SVA) and pelvic tilt (PT) are independent risk factors of osteoporosis-related fractures in women with osteoporosis. We clarified the SVA and PT to predict the incidence of osteoporosis-related fractures. Purpose: Sagittal alignment with osteoporosis women deteriorates with advancing age and sagittal alignment may indicate osteoporosis-related fractures in the future. However, whether the sagittal alignment predicts future osteoporosis-related fracture in patients with osteoporosis has not been clarified. We aimed to investigate the association between sagittal alignment and future osteoporosis-related fractures. Methods: This was a retrospective cohort study. Of the 313 participants (mean follow-up period, 2.9 years), 236 were included in the analysis. At baseline, we measured bone mineral density (BMD) of the lumbar spine and the femoral neck, sagittal vertical axis (SVA), thoracic kyphosis, pelvic incidence minus lumbar lordosis, sacral slope, pelvic tilt (PT), geriatric locomotive function scale (GLFS), two-step value, and stand-up test. The information on medications and the duration of treatment were reviewed from the medical records. Additionally, participants reported their history of falls at baseline. Multiple logistic regression analysis was used to determine the association of future osteoporosis-related fracture, and adjusted Odds ratios (OR) and 95% confidence interval (CI) were calculated with all predictors as covariates. All continuous variables were calculated using standardized OR (sOR). Results: Osteoporosis-related fractures occurred in 33 of 313 participants (10.5%). Multiple logistic regression analysis showed that a history of falls (OR =4.092, 95% CI: 1.029–16.265, p =0.045), SVA (sOR =4.228, 95% CI: 2.118–8.439, p <0.001), and PT (sOR =2.497, 95% CI: 1.087–5.733, p =0.031) were independent risk factors for future osteoporosis-related fractures. Conclusions: This study revealed the SVA and PT to predict osteoporosis-related fractures. Trial registration number and date of registration: UMIN000036516 (April 1, 2019) [ABSTRACT FROM AUTHOR]

To investigate structural characteristics associated with variations in slip behavior on the plate boundary in the Nankai subduction zone, we conducted seismic reflection surveys in the central‐western Nankai Trough. Data were processed by pre‐stack depth migration. The resulting depth map of the top of the subducting Philippine Sea plate shows detailed topographic features of the plate boundary, including subducting seamounts and large‐scale undulations of the plate surface. We report the presence of a structurally anomalous region, potentially with low velocity, in the overriding plate at the boundary between the zone of large coseismic slip during the 1946 Nankai earthquake and the area producing slow earthquakes. This anomaly appears to be related to depth‐dependent variations in plate boundary slip style and plate coupling in the central‐western Nankai Trough. Plain Language Summary: The central‐western Nankai Trough off southwestern Japan is one of the best locations to study variations in slip style on the plate boundary fault in subduction zones because the fault slip distribution during the latest great earthquake, the distribution of slow earthquakes, and interplate coupling are known from previous studies. We conducted seismic surveys along densely distributed survey lines to image detailed subsurface structures in the central‐western Nankai Trough. A three‐dimensional map of the plate boundary fault geometry was created from seismic profiles used in this study. We found a structural anomaly, interpreted as a low‐velocity zone in the overriding plate, at the boundary between the slip zone of great earthquakes and the zone of slow earthquakes. This anomaly might be related to the variation of the plate boundary fault slip styles. Key Points: The topography of the subducting plate is mapped with densely spaced seismic profiles in the central‐western Nankai TroughAn arcuate structural anomaly in the overriding plate ∼100 km long with potentially low velocity coincides with the Tosabae TroughThe arcuate anomaly is located at the boundary between regions of strong and weak plate coupling [ABSTRACT FROM AUTHOR]

Winter thunderstorms in Japan have been recognized as an ideal target to observe high‐energy atmospheric phenomena thanks to low‐charge‐center cloud structures. During four winter seasons in Japan (from 2016 October to 2020 March), seven downward terrestrial gamma‐ray flashes (TGFs) were detected by gamma‐ray and broadband low‐frequency (LF: 0.8–500 kHz) monitors. All the detected TGFs took place at the initial stage of lightning flashes. Based on the LF observation, the seven downward TGFs in the present study can be classified into two types: energetic‐bipolar and small‐bipolar types. Three of them are energetic‐bipolar events, coincident with a high peak‐current LF pulse that originates from a negative return stroke with a peak current larger than 100 kA. The others are small‐bipolar events, followed by a negative bipolar LF pulse with a moderate peak current. Three of the four small‐bipolar events are multi‐pulse TGFs, while all of the energetic‐bipolar events in this study are single‐pulse TGFs. Plain Language Summary: Terrestrial gamma‐ray flashes (TGFs) are a transient high‐energy emission from lightning discharges. While a lot of upward TGFs have been detected by satellites, a few downward TGF have been detected by ground‐based experiments. Our detection network in Japan has detected seven downward TGFs in winter thunderstorms for 4 years. Lightning discharges associated with the downward TGFs were also monitored in the low‐frequency radio band. The low‐frequency pulses associated with the downward TGFs can be classified into two types. Correlation analysis of downward TGFs with gamma‐ray and low‐frequency observations is a powerful approach to reveal the production mechanism of TGFs. Key Points: Downward terrestrial gamma‐ray flashes (TGFs) in winter thunderstorms of Japan can be classified into two types based on low‐frequency (LF) observationsThree events were single‐pulse TGFs coincident with high peak‐current LF pulses of return strokesFour events were followed by moderate peak‐current LF pulses, and three of them are multi‐pulse TGFs [ABSTRACT FROM AUTHOR]

An n n Λ , which consists of two neutrons and a Lambda hyperon, is a multi-baryon system with no charge. Studying the n n Λ state would provide information about the Λ n interaction which has not been directly measured by a scattering experiment. The experiment (E12-17-003) was performed in order to search for the n n Λ state at Jefferson Lab. The n n Λ is expected to be produced by the (e , e ′ K +) reaction, which has sensitivity to both bound and resonance states if the natural width of the n n Λ is narrow enough to be observed as a peak. The experiment used gas targets of hydrogen and tritium for mass calibration and the n n Λ production, respectively. The mass calibration with H (e , e ′ K +) Λ / Σ 0 reactions gave the mass resolution of the Λ and Σ 0 each 3.5 MeV / c 2 FWHM, for the elementary reaction. A spectrum of 3 H (e , e ′ K +) X was obtained, and a simple model with a Λ n final state interaction was applied to reproduce the spectrum. [ABSTRACT FROM AUTHOR]

Enfortumab vedotin (EV) is a novel drug for the treatment of patients with advanced bladder cancer.1-4 Although EV may induce various cutaneous eruptions,1-4 miliaria-like eruptions as EV-induced cutaneous adverse events (cAEs) are rare. Enfortumab vedotin-induced cutaneous adverse events manifesting as miliaria-like eruptions with the presence of keratinocyte apoptosis in clinically intact skin Therefore, localized immune cell inflammation may have resulted in miliaria-like eruption, and the development of miliaria crystalline-like and miliaria rubra-like eruptions may have been associated with mild and moderate immune cell infiltration, respectively. [Extracted from the article]

Seismic wave extractions have been performed using ambient noise records observed by distributed acoustic sensing (DAS) technology. Extractions of microseisms can be investigated at a local scale using such DAS records observed in the ocean. Here, we show P and Scholte wave extractions from ambient seafloor noise observed by DAS along a submarine cable deployed off Cape Muroto in the Nankai subduction zone, Japan. The P waves can be observed at a frequency band of 0.1–0.3 Hz and up to a distance of 8 km. The distance at which the P waves can be observed is controlled by the P incident angle and the DAS sensitivity to the observable apparent velocity. Effective extractions of P and Scholte waves, corresponding to large intensity of wave‐wave interaction at the sea surface, are performed, indicating that the waves are originated from pressure field at the sea surface. Plain Language Summary: The density of seismic observations on land is typically higher than that in the ocean. However, higher‐density observations in both land and ocean regions can be made using the recently developed distributed acoustic sensing (DAS). In this study, we focus on the waves persistently propagating through the Earth, which are excited by ocean swell and are called microseisms. Ocean swell at the sea surface primarily excites surface waves: however, P and S waves excited by ocean swell, especially during tropical storms, were observed on a global scale. Because this indicates that body waves may be locally excited by sea surface disturbances, we investigate the problem using DAS records. Our results show that large amplitudes of P waves occur when an atmospheric low pressure passes through Japan, and those amplitudes become weak when the wave‐wave interaction intensity at the ocean surface is weak. Although many previous studies at global or regional scales have indicated that microseisms are originated from fluid disturbances at the sea surface, the current study observed the excitation of P and surface waves right beneath the sea surface disturbances. Key Points: P waves were extracted from ambient seafloor noise records observed by distributed acoustic sensing (DAS) at a frequency band of 0.1–0.3 Hz and up to a distance of 8 kmExtraction of P waves depends on weather conditions, particularly for wave‐wave interaction intensity at the sea surfaceThe distance at which the P waves emerge is controlled by the P incident angle and the DAS sensitivity to apparent velocities [ABSTRACT FROM AUTHOR]

The suitability of 'design' height amplification factors (HAF) for the purpose of seismic assessment of existing non-structural unreinforced masonry (URM) components with known strength was evaluated through a numerical study. Four building typologies were included that represented pre-1940 URM construction in Australia and New Zealand. Through pushover and incremental dynamic analyses, the effects of diaphragm flexibility and nonlinear building response on floor accelerations were studied. It was found that Australia/New Zealand code procedures include significant inelastic building behaviour that reduces HAF. An interpretation was made on the applicability of the assumptions in the context of assessing non-structural URM components. [ABSTRACT FROM AUTHOR]

The low-noise amplification of weak microwave signals is crucial for countless protocols in quantum information processing. Quantum mechanics sets an ultimate lower limit of half a photon to the added input noise for phase-preserving amplification of narrowband signals, also known as the standard quantum limit (SQL). This limit, which is equivalent to a maximum quantum efficiency of 0.5, can be overcome by employing nondegenerate parametric amplification of broadband signals. We show that, in principle, a maximum quantum efficiency of unity can be reached. Experimentally, we find a quantum efficiency of 0.69 ± 0.02, well beyond the SQL, by employing a flux-driven Josephson parametric amplifier and broadband thermal signals. We expect that our results allow for fundamental improvements in the detection of ultraweak microwave signals. [ABSTRACT FROM AUTHOR]

A surface acoustic wave (SAW) is utilized in diverse fields ranging from physics, engineering, to biology for transducing, sensing, and processing various signals. Optical measurement of the SAW provides valuable information since the amplitude and the phase of the displacement field can be measured locally with the resolution limited by the spot size of the optical beam. So far, optical measurement techniques rely on modulation of the optical path, phase, or diffraction associated with SAWs. Here, we demonstrate that SAWs can be measured with an optical polarimeter. We show that the slope of the periodically tilting surface due to the coherently driven SAW is translated into the angle of polarization rotation, which can be straightforwardly calibrated when polarimeters work in the shot-noise-limited regime. The polarimetric measurement of SAWs is, thus, beneficial for quantitative studies of SAW-based technologies. [ABSTRACT FROM AUTHOR]

In order to realize high performance burning plasmas in magnetic-confinement fusion devices, such as tokamaks, both bulk plasma transport and that of energetic fusion alpha-particles, which result from different scale fluctuations with different free energy sources, have to be reduced simultaneously. Utilizing the advantage of global toroidal non-linear simulations covering a whole torus, here, we found a new coupling mechanism between the low-frequency micro-scale electromagnetic drift-wave fluctuations regulating the former, while the high-frequency macro-scale toroidal Alfven eigenmode (TAE) regulates the latter. This results from the dual spread of micro-scale turbulence due to the macro-scale TAE not only in wavenumber space representing local eddy size but also in configuration space with global profile variations. Consequently, a new class of turbulent state is found to be established, where the turbulence is homogenized on the poloidal cross-section with exhibiting large-scale structure, which increases fluctuation levels and then both transports, leading to deterioration in the fusion performance. [ABSTRACT FROM AUTHOR]

Click here for the corresponding questions to this CME article. [ABSTRACT FROM AUTHOR]

The hydrogen/deuterium (H/D) isotope effect on a zonal flow and its configuration dependence are experimentally studied in a helical device, Heliotron J. The isotope dependence of a toroidally symmetric potential fluctuation in the frequency range of <∼4 kHz, a zonal flow, is observed in low-density electron cyclotron resonance heated plasmas in Heliotron J. In the standard configuration, the zonal flow interacting with turbulence is enhanced as the D gas fraction increases. The zonal flow is more dominated against turbulent fluctuation in D plasmas, which should have a favourable impact on turbulence transport. Interestingly, however, the opposite dependence of the zonal flow activity on the isotope ratio is also observed in the different magnetic configurations. The configuration dependence observed in this experiment could be one of the factors to explain the difference in the isotope effect of confinement improvement between tokamaks and helical devices. Impurities and radial electric field, which can also be influenced by isotope mass through the difference in neoclassical transport and plasma-wall interaction, have insignificant influences on the zonal flow behaviour in this experiment. [ABSTRACT FROM AUTHOR]

Around 17:00 on January 12, 2020 (UTC), radiation detectors installed at two locations with a 1.35 km separation in Kanazawa City, Japan, captured a total of four gamma‐ray enhancements. The first pair was simultaneously observed at the two locations at 17:03 and were abruptly terminated by a lightning discharge. The remaining two enhancements were also nearly simultaneously observed ∼3 min later, and one of them was also terminated by another lightning discharge. At the last termination, a downward terrestrial gamma‐ray flash and a negative energetic in‐cloud pulse were observed. Both pairs were associated with thundercloud cells. In the first pair, simultaneous detection in two locations 1.35 km apart suggests either a gamma‐ray glow emerged in‐between and time variability of its intensity were directly observed or there were two (or more) gamma‐ray glows in the cell which reached the two detectors coincidentally. In the latter pair, the peak time in the downwind detector was ∼40 s later than that of the upwind detector. If the irradiation region moved with the cell, it would have taken ∼110 s. The discrepancy suggests either the glow moved 2.5 times faster than the cell or there were two (or more) glows in the cell. Also, the fact that the thunderstorm cell hosting the latter glows experienced the lightning discharge ∼3 min before suggests that the strong electric field in the cell can develop within a few minutes. Plain Language Summary: Thunderclouds sometime emit gamma rays with a duration of minutes, which are called "gamma‐ray glow". It is bremsstrahlung emission from high‐energy electrons accelerated in the cloud. At around 17:00 (UTC) January 12, 2020, two radiation detectors installed 1.35 km apart in Kanazawa City, Japan, captured a total of four count rate enhancements. The first two disappeared with a lightning discharge, and the last one with another lightning, in this case accompanied by an intense gamma ray flash called a "downward terrestrial gamma‐ray flash" (TGF). The overall behavior is similar to another gamma‐ray glow observed in the same location on January 2018 (e.g. Wada et al. 2019, https://doi.org/10.1038/s42005-019-0168-y). This is also the third report of gamma‐ray glow termination associated with both lightning discharges and TGFs. However, while the 2018 event can be explained well by assuming that the electron acceleration region moves with the thundercloud cell (monitored by rainfall map) and then terminated by a lightning discharge, the time profiles of the four current events cannot. To explain the behavior of the 2020 data, new models such as electron acceleration region(s) rapidly emerging in a thundercloud cell, and/or multiple electron acceleration regions co‐existing in a single cell, are discussed. Key Points: Four gamma‐ray enhancements were observed at two locations 1.35 km apart along the wind direction, and their time profiles were analyzedThe termination of three of them was also recorded. The last one was associated with a downward terrestrial gamma‐ray flash and a negative energetic in‐cloud pulseThe acceleration region of gamma‐ray glows in a thundercloud can develop within a few minutes after experiencing a discharge [ABSTRACT FROM AUTHOR]

We have demonstrated a GaN growth technique in the Na flux method to confine c-, (a+c)-, and a-type dislocations around the interface between a Na flux GaN crystal and a GaN layer grown by metalorganic chemical vapor deposition (MOCVD) on a (0001) sapphire substrate. Transmission electron microscopy (TEM) clearly revealed detailed interface structures and dislocation behaviors that reduced the density of vertically aligned dislocations threading to the Na flux GaN surface. Submicron-scale voids were formed at the interface above the dislocations with a c component in MOCVD-GaN, while no such voids were formed above the a-type dislocations. The penetration of the dislocations with a c component into Na flux GaN was, in most cases, effectively blocked by the presence of the voids. Although some dislocations with a c component in the MOCVD-GaN penetrated into the Na flux GaN, their propagation direction changed laterally through the voids. On the other hand, the a-type dislocations propagated laterally and collectively near the interface, when these dislocations in the MOCVD-GaN penetrated into the Na flux GaN. These results indicated that the dislocation propagation behavior was highly sensitive to the type of dislocation, but all types of dislocations were confined to within several micrometers region of the Na flux GaN from the interface. The cause of void formation, the role of voids in controlling the dislocation behavior, and the mechanism of lateral and collective dislocation propagation are discussed on the basis of TEM results. [ABSTRACT FROM AUTHOR]

The two-dimensional magnetic recording (TDMR) exploits two-dimensional signal processing using the neighboring read-back waveforms. We allocate dual readers for the intended tracks and evaluate the effects of head skew angle on the bit error rate performance in partial response class-I maximum likelihood system with a two-dimensional finite impulse response filter using two read-back waveforms under TDMR R/W channel specifications of 4 Tbit/in.2. The results show that the effect of positive skew angle is larger than that of negative skew angle, and the center of skew angle should be shifted to minus direction. [ABSTRACT FROM AUTHOR]

In this study, the characteristics of side-projected planar shock waves propagating through grid turbulence were investigated using a counter-driver shock tube. At the location of visualization of the shock–turbulence interactions, the range of the shock Mach numbers was M s = 1.01 - 1.15 and the representative values of the turbulent Mach numbers M t ~ were 0.005 - 0.014 . The interaction length between the shock wave and grid turbulence was in the range approximately from - 50 to 300 times the integral length scale of the turbulence. For the interaction involving the strongest turbulence with M t ~ = 0.014 , the weakest planar shock wave with M s = 1.01 was largely deformed and could not be detected on the projected shadowgraph and schlieren images. The density changes on the grayscale in the projected images of the shock waves weakened and expanded multidimensionally. This undetectable profile of the shock wave could indicate that the shock wave locally lost discontinuous property change profile. The shock waves with M s ≥ 1.05 did not show the undetectable profile in the projected image. In these cases, the projected thickness of the shock wave increased with an increase in the interaction length. The increase in the projected thickness became larger as the turbulent Mach number increased, and the shock Mach number decreased. [ABSTRACT FROM AUTHOR]

3-D magnetic recording using microwave-assisted magnetic recording (MAMR) and a spin-torque oscillator (STO) for reading has been proposed as a candidate for prospective recording technologies. In 3-D magnetic recording using STO as a reading, the temporal magnetization dynamics of the STO has the fluctuations for frequency and amplitude which depend on the recorded pattern. In our previous work, we have constructed the STO signal model considering both amplitude and frequency fluctuations to develop a combined signal processing using the amplitude and frequency fluctuation detections. We have applied the STO signal model to the low-density parity-check (LDPC) coding and iterative decoding system with the individual detectors for amplitude modulation (AM) and frequency modulation (FM). Furthermore, we have reported that the dual STO reading system with only AM detection provides the improvement of the bit error rate (BER) performance. In this study, we propose the dual STO reading system with AM–FM combined detection in the hope that the finite impulse response (FIR) filter output distribution will be easier to detect with the decoder. We evaluate the BER performances of the proposed system for carrier-to-noise ratio (CNRS) of the system noise under an areal recording density of 1 Tbits/in2 specification with bit-pattern medium stricture by computer simulation. The results show that the FIR filter output distribution for our proposed dual STO reading system at an FM detector output has become sharper, and the proposed system achieves the “No errors” with CNRS less by about 3.5 dB than the single STO reading system. [ABSTRACT FROM AUTHOR]

A 3-D magnetic recording using microwave-assisted magnetic recording (MAMR) and a spin-torque oscillator (STO) as a reading sensor has been proposed as a candidate for the prospective recording technologies. In the STO reading system, the temporal magnetization dynamics of the STO vary not only in amplitude but also in frequency, depending on the recorded pattern. Therefore, we have constructed the STO signal model which considers both amplitude and frequency fluctuations to develop a combined signal processing using the detection of amplitude and frequency fluctuations. Furthermore, we have applied the STO signal model to the low-density parity-check (LDPC) coding and iterative decoding system with the detectors for amplitude modulation (AM) and frequency modulation (FM) and have proposed the AM–FM combined detection. Then, we have evaluated the bit error rate (BER) performances by computer simulation. The results show that the system with AM–FM combined detection improves the performance of the LDPC coding and iterative decoding system, which achieves “no errors” at the carrier-to-noise ratio for system noise (CNR $_{S}) = 15.9$ dB, whereas the AM and FM detections require CNR $_{S} = 21.2$ and 17.2 dB. [ABSTRACT FROM AUTHOR]

We have previously focused on a log-likelihood ratio (LLR) computed as the decoding reliability by $a$ posteriori probability (APP) decoder on the low-density parity-check (LDPC) coding and iterative decoding system for the shingled magnetic recording (SMR). Then, we clarified that the LLR modulator applying a neural network realizes an effective iterative decoding. In this article, we propose a new neural network LLR modulator considering magnetic transition information obtained from LLRs to reduce the influence of intersymbol interferences (ISIs). [ABSTRACT FROM AUTHOR]

Purpose: Tryptophan metabolites have immunomodulatory functions, suggesting possible roles in cancer immunity. Methods: Plasma tryptophan metabolites were measured using liquid chromatography/mass spectrometry before immune checkpoint inhibitors (ICIs) in patients with non-small cell lung cancer (NSCLC). Results: The 19 patients with NSCLC had significantly lower levels of tryptophan (p = 0.002) and xanthurenic acid (p = 0.032), and a significantly higher level of 3-hydroxyanthranilic acid (3-HAA) (p = 0.028) compared with the 10 healthy volunteers. The patients achieving objective responses had significantly lower levels of 3-HAA than those who did not (p = 0.045). Receiver operating characteristic analyses determined that the cutoff value of 3-HAA for objective response was 35.4 pmol/mL (sensitivity: 87.5% and specificity: 83.3%). The patients with 3-HAA < 35.4 pmol/mL had significantly longer median progression-free survival (7.0 months) than those without (1.6 months, p = 0.022). Conclusions: Tryptophan metabolites may have a potential for predicting the efficacy of ICIs. Registration number: University Hospital Medical Information Network Clinical Trial Registry 000026140. [ABSTRACT FROM AUTHOR]

STUDY QUESTION Is oocyte cryopreservation an applicable option for fertility preservation in unmarried patients with haematological malignancies? SUMMARY ANSWER Oocyte cryopreservation via the vitrification method is accessible and may be considered an option for fertility preservation in unmarried patients with haematological malignancies. WHAT IS KNOWN ALREADY Haematological malignancies are most commonly observed amongst adolescent and young adult women. Although the survival rate and life expectancy of those with haematological malignancies have improved, chemotherapy and radiotherapy may impair their reproductive potential. Oocyte cryopreservation is thus an ideal option to preserve their fertility. STUDY DESIGN, SIZE, DURATION This study retrospectively evaluated 193 unmarried patients (age: 26.2 ± 0.4 years) with haematological malignancies, who consulted for oocyte cryopreservation across 20 different fertility centres in Japan between February 2007 and January 2015. The primary outcome measures were the oocyte retrievals and oocyte cryopreservation outcomes. The secondary outcome measures were the outcomes following oocyte warming for IVF. PARTICIPANTS/MATERIALS, SETTING, METHODS The patients had commenced ovarian stimulation cycles via antagonist, agonist, natural and minimal methods for oocyte retrievals, defined according to the treatment strategy of each respective fertility centre. A vitrification method using the Cryotop safety kit was used for oocyte cryopreservation. ICSIs were used for insemination of warmed oocytes. The endometrial preparation method for embryo transfer was hormonal replacement therapy, except in the case of a patient who underwent a spontaneous ovulatory cycle. MAIN RESULTS AND THE ROLE OF CHANCE Among 193 patients, acute myeloid leukaemia (n = 45, 23.3%) was most common, followed by acute lymphoid leukaemia (n = 38, 19.7%) and Hodgkin's lymphoma (n = 30, 15.5%). In total, 162 patients (83.9%) underwent oocyte retrieval, and oocytes were successfully cryopreserved for 155 patients (80.3%). The mean number of oocyte retrieval cycles and cryopreserved oocytes were 1.7 ± 0.2 and 6.3 ± 0.4, respectively. As of December 2019, 14 patients (9.2%) had requested oocyte warming for IVF. The survival rate of oocytes after vitrification-warming was 85.2% (75/88). The rates of fertilisation and embryo development were 80.0% (60/75) and 46.7% (28/60), respectively. Ten patients (71.4%) had successful embryo transfers, and seven live births (50.0%) were achieved. LIMITATIONS, REASONS FOR CAUTION This study was limited by its retrospective nature. Additionally, there remains an insufficient number of cases regarding the warming of vitrified oocytes to reliably conclude whether oocyte cryopreservation is effective for patients with haematological malignancies. Further long-term follow-up study is required. WIDER IMPLICATIONS OF THE FINDINGS Oocyte retrieval and oocyte cryopreservation were accessible for patients with haematological malignancies; however, the number of oocyte retrievals may have been limited due to the initiation of cancer treatments. Acceptable embryonic and pregnancy outcomes could be achieved following oocyte warming; therefore, our results suggest that oocyte cryopreservation can be considered an option for fertility preservation in patients with haematological malignancies. STUDY FUNDING/COMPETING INTERESTS This research received no specific grant from any funding agency in the public, commercial or not-for-profit sectors. The authors declare no conflict of interest. TRIAL REGISTRATION NUMBER N/A [ABSTRACT FROM AUTHOR]

Summary: Epidermal growth factor receptor inhibitors (EGFRIs) frequently cause cutaneous adverse effects such as papulopustular eruptions. However, the mechanism of the reactions remains unclear. To assess the pathological mechanism of cutaneous adverse reactions caused by EGFRIs, we investigated whether EGFRIs have an influence on the innate immune response of the skin. Levels of human β‐defensins (hBDs), which serve as the first line of defence against infection by pathogenic microorganisms, in the stratum corneum samples of patients treated with EGFR. monoclonal antibodies were measured before and after starting therapy. There were no obvious trends in hBD production in patients without eruptions, whereas a significant decrease in hBD1 and hBD3 production and a nonsignficant decrease in hBD2 production were observed in patients who developed papulopustular eruptions. Our results suggest that a reduction in hBD contributes to the increased incidence of papulopustular eruptions. [ABSTRACT FROM AUTHOR]

A pair of counter-rotating symmetric vortices has been observed in the wake behind a stationary obstacle (dust void) in a flowing dusty plasma. A strongly coupled dusty plasma flow with controllable velocity is generated and directed toward the void in a novel experiment. In the unsteady laminar flow regime, the curl of the fluid flow velocity along the boundary layer of the void generates the vortex pair behind the void. Particle image velocimetry analysis of high speed image data clearly depicts the flow pattern and the vorticities. The shear viscosity of the dusty plasma fluid along with the experimental parameters is considered to obtain the Reynolds number range for the evolution of the vortices. Molecular dynamics simulation is also performed to support the experimental observation. [ABSTRACT FROM AUTHOR]

Photoconductivity (PC) of Si/Ge structures with Ge quantum dots (QDs) grown on the Si(100) surfaces covered with the ultrathin, about 0.3-0.5 nm thick, SiO2 films is studied as a function of the interband light intensity under various lateral voltages. The structures exhibit PC with steps and a step with a peak at the step edge for low- and high-temperature grown structures, respectively. These PC features are associated with the impact ionization of QD-related excitons. The PC at step edges increases by several orders of magnitude for a certain value which is governed by the balance between rates of photo-generation, recombination, and impact ionization of excitons. The electron localization deeper in Si from the Ge QD layer in conjunction with a narrow binding-energy distribution of excitons is suggested to be the main reason that provides the sharpness of PC steps. The PC appears to be very sensitive to the impact ionization and QD preparation conditions. This allows revealing the specific characteristics of QD structures, related to their electronic and structural properties. [ABSTRACT FROM AUTHOR]

BiFeO3 (BFO) shows both ferroelectricity and magnetic ordering at room temperature, but its ferromagnetic component, which is due to spin canting, is negligible. Substitution of transition-metal atoms such as Co for Fe is known to enhance the ferromagnetic component in BFO. In order to reveal the origin of such magnetization enhancement, we performed soft x-ray absorption spectroscopy (XAS) and soft x-ray magnetic circular dichroism (XMCD) studies of BiFe1-xCoxO3 (x = 0 to 0.30) (BFCO) thin films grown on LaAlO3(001) substrates. The XAS results indicated that the Fe and Co ions are in the Fe3+ and Co3+ states. The XMCD results showed that the Fe ions show ferromagnetism, while the Co ions are antiferromagnetic at room temperature. The XAS and XMCD measurements also revealed that part of the Fe3+ ions are tetrahedrally co-ordinated by oxygen ions but that the XMCD signals of the octahedrally coordinated Fe3+ ions increase with Co content. The results suggest that an impurity phase such as the ferrimagnetic γ-Fe2O3 which exists at low Co concentration decreases with increasing Co concentration and that the ferromagnetic component of the Fe3+ ion in the octrahedral crystal fields increases with Co concentration, probably reflecting the increased canting of the Fe3+ ions. [ABSTRACT FROM AUTHOR]

Summary: Background: Taxanes are the current first‐line treatment for advanced cutaneous angiosarcoma (CAS) for patients who are considered difficult to treat with doxorubicin owing to advanced age or comorbidity. However, no effective second‐line therapy for such patients has been established. Methods: We designed a single‐arm prospective observational study of eribulin mesylate (ERB) administered at a dose of 1·4 mg m−2 on days 1 and 8 in a 21‐day cycle. Patients with advanced CAS who were previously treated with a taxane and were scheduled to begin ERB treatment were enrolled. The primary endpoint was overall survival (OS) and the secondary endpoints were response rate (RR), progression‐free survival (PFS) and toxicity assessment. Results: We enrolled a total of 25 patients. The median OS and PFS were 8·6 months and 3·0 months, respectively. The best overall RR was 20% (five of 25). In total, 16 grade 3/4 severe adverse events (SAEs) occurred; however, all patients recovered. Patients who achieved partial response or stable disease as best response had longer OS than those with progressive disease (median OS not reached and 3·3 months, respectively; P < 0·001). Patients who did not experience SAEs showed longer OS than those who did (median OS 18·8 months and 7·5 months, respectively; P < 0·05). Patients with distant metastasis had shorter median OS than those with locoregional disease, but without statistically significant difference. Conclusions: ERB showed a promising RR and is a potential candidate for second‐line treatment for patients with CAS, after treatment with taxanes. However, owing to the occurrence of SAEs in over half of the participants, caution should be exercised regarding ERB use in elderly patients. What is already known about this topic? Taxanes are the current first‐line treatment for patients with advanced cutaneous angiosarcoma (CAS) who are considered difficult to treat with doxorubicin owing to advanced age or comorbidity.No effective therapy for taxane‐resistant CAS has been established thus far.Eribulin suppresses microtubule polymerization and elicits an antitumour effect similar to that of taxanes. What does this study add? In our single‐arm prospective observational study to evaluate the efficacy of eribulin for treating patients with advanced CAS who previously received taxanes, the median overall survival and progression‐free survival were 8·6 and 3·0 months, respectively.Response rates at weeks 7, 13 and 25 were 20%, 17% and 14%, respectively.Although 16 grade 3/4 severe adverse events occurred, all patients recovered.Eribulin showed a promising response rate and is a potential candidate for second‐line treatment in CAS after taxane treatment. Linked Comment:Smrke and Benson. Br J Dermatol 2020; 183:797–798. What is already known about this topic? Taxanes are the current first‐line treatment for patients with advanced cutaneous angiosarcoma (CAS) who are considered difficult to treat with doxorubicin owing to advanced age or comorbidity.No effective therapy for taxane‐resistant CAS has been established thus far.Eribulin suppresses microtubule polymerization and elicits an antitumour effect similar to that of taxanes. What does this study add? In our single‐arm prospective observational study to evaluate the efficacy of eribulin for treating patients with advanced CAS who previously received taxanes, the median overall survival and progression‐free survival were 8·6 and 3·0 months, respectively.Response rates at weeks 7, 13 and 25 were 20%, 17% and 14%, respectively.Although 16 grade 3/4 severe adverse events occurred, all patients recovered.Eribulin showed a promising response rate and is a potential candidate for second‐line treatment in CAS after taxane treatment. Linked Comment:Smrke and Benson. Br J Dermatol 2020; 183:797–798. [ABSTRACT FROM AUTHOR]

Background: Surgery is the gold standard for basal cell carcinomas (BCC). Current recommended surgical margins for BCCs are determined from studies in Caucasian populations. However, the appropriate surgical margins for BCCs in non‐white races are unclear. Objectives: To investigate the accuracy of preoperative determination of clinical tumour borders and appropriate surgical margins in Japanese patients with BCC. Methods: The maximum calculated differences in distance between the preoperatively determined surgical margins and the actual histologic tumour side margins were considered as 'accuracy gaps' of clinical tumour borders. Estimated side margin positivity rates (ESMPRs) with narrower (2 and 3 mm) surgical margins were calculated on the basis of the accuracy gaps. Results: Overall, 1000 surgically excised BCCs from 980 Japanese patients were included. The most frequent histologic subtype was nodular BCC (67%). The median accuracy gap was 0.3 mm [interquartile range (IQR): −0.5 to +1 mm]. The ESMPRs with 2‐ and 3‐mm surgical margins were 3.8% and 1.4%, respectively. Only the ESMPRs between the well‐defined (n = 921) and poorly defined clinical tumour border groups (n = 79) showed statistical difference [2‐mm margin: 3.1% vs. 11.7%, OR: 3.89, 95% confidential interval (CI): 1.41–10.71, P <0.01; 3‐mm margin: 0.97% vs. 6.3%, OR: 6.58, 95% CI: 1.67–25.99, P <0.01]. No significant differences in ESMPRs were noted in other subgroups including risk classifications. Conclusions: The determined clinical tumour border accuracy gaps in this Japanese cohort were negligible. Dermatologic surgeons may use narrower surgical margins with acceptable margin positivity rates. The clarity of clinical tumour borders could be an appropriate guide for selection of different surgical margins in the Japanese cohort. [ABSTRACT FROM AUTHOR]

Alfvén eigenmodes destabilized by energetic particles in Heliotron J, a low magnetic shear helical axis stellarator/heliotron with four toroidal equilibrium field periods, are investigated with MEGA, a hybrid simulation code for energetic particles interacting with a magnetohydrodynamic fluid. The objectives of this study are to validate the MEGA simulation results on Alfvén eigenmodes in Heliotron J, and to clarify the properties of Alfvén eigenmodes. The experimentally observed global Alfvén eigenmode (GAE) was reproduced with MEGA simulations based on the experimental bulk plasma temperature and density profiles. Beside GAE, GAE was also observed with lower amplitude and linear growth rate. The frequency and spatial location of GAE are close to those of the experimentally observed energetic particle mode (EPM). For GAE, it was found that the three-dimensional spatial profile of the GAE was primarily composed of n = 2 harmonics while the contribution from the other toroidal mode numbers such as n = 2 ± iNfp was weak, where 'i' and 'Nfp' are arbitrary integer and toroidal field period, respectively. This indicates that the coupling of harmonics with the same toroidal mode number through toroidicity is dominant for the GAE spatial profile, and the coupling with the different toroidal mode numbers through helicity and bumpiness has minor effects. For GAE, the coupling of harmonic through toroidicity is weaker than that of GAE. The non-linear evolutions of the GAE and GAE destabilized by energetic particles with a bump-on-tail distribution and a slowing-down distribution were compared. Weak dependence of the linear growth rate for both and modes on charge-exchange time were implied. [ABSTRACT FROM AUTHOR]

Helical distortion of the core part of tokamak plasma, which is called a helical core or a long-lived mode, is investigated by means of three-dimensional magnetohydrodynamic equilibrium calculations. It is found that the magnitude of the helical distortion strongly depends on the shape of the plasma boundary for weakly reversed shear plasmas. The triangularity of the boundary enhances the amplitude of helical distortion. In addition, reversed D-shape plasmas also exhibit a helical core. It is also found that the triangularity lowers the critical β for the onset of a helical core; furthermore, the critical β vanishes when the triangularity exceeds a certain value. On the other hand, the influence of the ellipticity on the amplitude of helical distortion strongly depends on β. The ellipticity enhances the amplitude at high β, while it reduces the amplitude at low β. [ABSTRACT FROM AUTHOR]

The nonlinear evolution of electromagnetic instabilities in reversed shear plasmas is investigated by means of global gyrokinetic simulations. It is found that the kinetic infernal mode (KIM), which is a pressure-driven instability with low to intermediate toroidal mode number excited in a region of low magnetic shear, is unstable at high β, while the ion temperature gradient mode is unstable at low β, where β is the ratio of the plasma kinetic pressure to the magnetic pressure. The β threshold of the KIM is much lower than that of the kinetic ballooning mode (KBM) appearing in a normal shear plasma, while both the KIM and KBM are strong at the unfavorable curvature region, and the KIM has the same parity as the KBM. Nonlinear simulations show that the KIM gets saturated by exciting strong zonal flows and fluctuations of low toroidal mode number. The amplitude of the KIM turbulence is similar to that of the KBM turbulence in spite of the fact that the linear growth rate of the KIM is much higher than that of the KBM. This is because the excitation of zonal flows and fluctuations at low toroidal mode number is stronger in the reversed shear plasma than that of the normal shear plasma. On the other hand, the energy flux and particle flux due to the KIM turbulence are about two or three times larger than those by the KBM turbulence. [ABSTRACT FROM AUTHOR]

The polarity determination process of sputter-deposited aluminum nitride (AlN) on metals has been analyzed using aberration corrected atomic resolution scanning transmission electron microscope. Direct growth of c-axis orientated AlN on face centered cubic metals (fcc) (111) with the local epitaxy has been observed, and the polarity was determined at the AlN/metal interface. We found that the AlN polarity can be controlled by the base metal layer: N-polarity AlN grows on Pt(111) while Al-polarity AlN forms on Al(111). Based on these results, the growth mechanism of AlN on metals is discussed. [ABSTRACT FROM AUTHOR]

The rapid development in designs and fabrication techniques of superconducting qubits has made coherence times of qubits longer. In the future, however, the radiative decay of a qubit into its control line will be a fundamental limitation, imposing a trade-off between fast control and long lifetime of the qubit. Here, we break this trade-off by strongly coupling another superconducting qubit along the control line. This second qubit, which we call "Josephson quantum filter" (JQF), prevents the first qubit from emitting microwave photons and thus suppresses its relaxation, while transmitting large-amplitude control microwave pulses due to the saturation of the quantum filter, enabling fast qubit control. This device functions as an automatic decoupler between a qubit and its control line and could help in the realization of a large-scale superconducting quantum processor by reducing the heating of the qubit environment and the crosstalk between qubits. The trade-off between long lifetime and inevitable radiative decay to a control line has become a key limitation for superconducting qubits. Here, the authors break the trade-off by coupling another qubit to the control line of the first one to suppress its relaxation, while enabling fast qubit control. [ABSTRACT FROM AUTHOR]

Here, we report on a study of seed plasmas produced by non-resonant 2.45 GHz microwave heating in Heliotron J, which is useful for plasma start-up by neutral beam injection (NBI) under the conditions of low beam power (<1 MW), low accerelation voltage (<30 kV) and small device size (∼1 m). The pre-ionization technique using the non-resonant heating produced the electron density in the order of 1017–1018 m−3 with the energy exceeds the CII ionization potential (30 eV). The existence of the relativistic electrons, which was essential to produce the seed plasmas, was confirmed experimentally during the pre-ionization phase by the synchrotron radiation and the hard x-ray emission measurements. The production mechanism of the relativistic electrons was considered to be stochastic interactions between the electrons and the microwave-frequency field. By optimizing the additional gas fueling during the microwave launch, a higher seed-plasma density more than 4 × 1018 m−3 was obtained, resulting that a rapid density evolution after NBI turn-on was successful even in the low NBI power (0.3 MW) condition. The seed plasmas produced by the pre-ionization method is useful to realize the plasma start-up under low absorption power condition in larger heliotron/stellarator devices such as perpendicular NBI in W7-X or deuterium NBI in LHD. [ABSTRACT FROM AUTHOR]