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We developed a Handheld Integrating Sphere Snow Grain Sizer (HISSGraS) for field use to measure the specific surface area (SSA) of snow. In addition to snow samples, HISSGraS can directly measure snow surfaces and snow pit walls. The basic measurement principle is the same as that of the IceCube SSA instrument. The retrieval algorithm for SSA from reflectance employs two conversion equations formulated using spherical and nonspherical grain shape models. We observed SSAs using HISSGraS, IceCube and the gas adsorption method in a snowfield in Hokkaido, Japan. Intercomparison of the results confirmed that with HISSGraS direct measurement, SSA profile observations can be completed in just ~1/10 the time required for measurement of snow samples. Our results also suggest that HISSGraS and IceCube have similar accuracy when the same snow samples are measured using the same grain shape model. However, SSAs of near-surface snow layers measured using the three techniques exhibited some biases, possibly due to rapid snow metamorphism or melting during measurement and some technical issues with optical techniques. When excluding SSA data for the surface layer, which metamorphosed remarkably during measurement, IceCube- and HISSGraS-derived SSAs correlated strongly with those obtained by gas adsorption and HISSGraS accuracy is 21–34%.

Motors for electric drive systems applied to electric vehicles (EVs) and plug-in hybrid electric vehicles (PHEVs) need to be compact and to have high power density to reduce vehicle weight, to expand the living space, and to lower costs. Several means of reducing the size of motors can be utilized. In this study, we focused on shortening the axial length of the stator coil. The axial length of the entire motor can be shortened by reducing the axial length of the stator coil end, and the length of the frame that houses the motor can be reduced. In our previous report, we proposed a permanent magnet synchronous motor that has a stator consisting of a stator coil with rectangular wires joined at the axial center of the stator core to shorten the axial length of the entire motor. However, one of the issues with the proposed coil, the possibility of the coil falling off due to thermal stresses generated in the coil, had not been considered. In addition, a large difference was found between the measured and analyzed coil temperatures, along with a problem in the evaluation of high-frequency iron loss. As a result, thermal stress could not be evaluated accurately. Therefore, we conducted a preliminary study to evaluate the thermal stress of the coil. The study, reported herein, included an investigation on the effect of harmonic iron loss on the temperature of various parts of the motor to improve the accuracy of loss analysis. We directly measured the iron loss of electromagnetic steel sheets at various frequencies to investigate up to what frequency the iron loss data used in the building factor calculation for the iron loss analysis would be required. Then, temperature analysis was performed at the operating point under the most severe temperature conditions, and shear stress was evaluated using the calculated temperatures of each part to determine whether or not the welding-less coils would pull out. As a result of our review, the maximum frequency of iron loss data for electromagnetic steel sheets used to calculate the building factor for iron loss calculations was found to be at least 20 kHz. In addition, the coil temperature was within ±10 K of the value obtained when the motor was designed under the condition of no mating area, and the motor with the welding-less coil exhibited the same characteristics as those of the designed value. In the next step, the coil’s adhesion strength exceeding the thermal stress, we found that the insulation configuration did not break under thermal stress and that coil dislocation did not occur. Therefore, we found that the welding-less coils are useful as coils constituting a motor.

Sea ice monitoring is key to analyzing the Earth’s climate system. Long-term sea ice extent (SIE) has been continuously monitored using various spaceborne passive microwave radiometers (PMRs) since November 1978. As the lifetime of a satellite is usually approximately 5 years, bias caused by differences in PMRs should be eliminated to obtain objective SIE trends. Most sea ice products have been analyzed for long-term trends with a bias adjustment based on the coarse resolution special sensor microwave imager (SSM/I) in operation for the longest period. However, since 2002, Japanese microwave radiometers of the Advanced Microwave Scanning Radiometer (AMSR) series, which have the highest spatial resolution in PMR, have been available. In this study, we developed standardization techniques for processing SIE including calibration of the brightness temperature (TB), tuning the sea ice concentration (SIC) algorithm, and adjusting the SIC threshold to retrieve a consistent SIE trend based on the AMSR for the Earth Observing System (AMSR-E, one of the AMSR that operated from May 2002 to October 2011). Analysis results showed that the root-mean-square error between AMSR-E SICs and those of moderate resolution imaging spectroradiometer (MODIS) was 15%. In this study, SIE was defined as the sum of the areas where the AMSR-E SIC was >15%. When retrieving SIE, we adjusted the SIC threshold for each PMR to be consistent with the SIE calculated based on the 15% SIC threshold for AMSR-E. We then calculated a time-series of the SIE trends over approximately 45 years using the adjusted SIE data. Therefore, we revealed the dramatic decrease in global sea ice extent since 1978. This technique enables retrieval of more accurate long-term sea ice trends for more than half a century in the future.

Abstract Recent observations of macroscopic quantum condensation using electron-hole (e-h) bilayers have activated the research of its application to electronics. However, to the best of our knowledge, no attempts have been made to observe the condensation in silicon, the major material in electronics, due to the lack of technology to form closely-packed and uniform bilayers. Here, we propose a method to meet such requirements. Our method uses the transient response of carriers to a rapid gate-voltage change, permitting the self-organized bilayer formation at the metal-oxide-semiconductor interface with an e-h distance as small as the exciton Bohr radius. Recombination lifetime measurements show that the fast process is followed by a slow process, strongly suggesting that the e-h system changes its configuration depending on carrier density. This method could thus enable controlling the phase of the e-h system, paving the way for condensation and, ultimately, for low-power cryogenic silicon metal-oxide-semiconductor devices.

Weyl superconductivity is a topological phase in three-dimensional crystals in which the Weyl equation describes quasiparticle excitation near band-touching points in momentum space called Weyl nodes. For quasicrystals which lack translational symmetry, a theory of Weyl superconductivity has not been established, in spite of recent extensive studies on quasicrystalline topological phases. Here, we demonstrate the occurrence of quasicrystalline Weyl superconductivity by extending the definition of Weyl superconductivity to periodically stacked, two-dimensional superconducting quasicrystals. We identify quasicrystalline Weyl nodes—topologically protected point nodes in one-dimensional momentum space corresponding to the stacking direction—in terms of a topological invariant given by a change in the Bott index in quasicrystalline layers. We find that these Weyl nodes exist in pairs and that Majorana zero-energy modes protected by the nonzero Bott index between a pair of quasicrystalline Weyl nodes appear on surfaces. These Majorana zero modes form an infinite number of arcs in momentum space, densely and quasiperiodically distributed as a function of momentum in the direction of surfaces within each quasicrystalline layer. In Ammann-Beenker (Penrose) quasicrystals, the quasiperiodicity of Majorana arcs is governed by the silver (golden) ratio associated with the quasicrystalline structure.

Iron is one of the most abundant trace elements in the human body, however, detection at a single-cell level with redox status is challenging. Here, the authors demonstrate magnetometry of neurons with a microscale magnetometer using a superconducting flux qubit, and Fe (III) ions in the cells are identified at a single-cell level spatial resolution.

Drag between the electron and the hole layers formed in a silicon-on-insulator MOSFET, with the estimated interlayer distance as small as 18 nm, is investigated. The drag resistance is measured at 10 K and mapped on the plane defined by the electron and hole densities. Analysis shows that the Coulomb drag predominates over the competing virtual-phonon drag. The observed drag resistance is as large as 10 ^3 -10 ^4 Ω, indicating strong Coulomb interaction between the electron and hole layers.

Increasing water flowing into the Arctic Ocean affects oceanic freshwater balance, which may lead to the thermohaline circulation collapse and unpredictable climatic conditions if freshwater inputs continue to increase. Despite the crucial role of ocean inflow in the climate system, less is known about its predictability, variability, and connectivity to cryospheric and climatic patterns on different time scales. In this study, multi-scale variation modes were decomposed from observed daily and monthly snowcover and river flows to improve the predictability of Arctic Ocean inflows from the Mackenzie River Basin in Canada. Two multi-linear regression and Bayesian neural network models were used with different combinations of remotely sensed snowcover, in-situ inflow observations, and climatic teleconnection patterns as predictors. The results showed that daily and monthly ocean inflows are associated positively with decadal snowcover fluctuations and negatively with interannual snowcover fluctuations. Interannual snowcover and antecedent flow oscillations have a more important role in describing the variability of ocean inflows than seasonal snowmelt and large-scale climatic teleconnection. Both models forecasted inflows seven months in advance with a Nash–Sutcliffe efficiency score of ≈0.8. The proposed methodology can be used to assess the variability of the freshwater input to northern oceans, affecting thermohaline and atmospheric circulations.

Abstract This paper discusses the cloud/clear discrimination algorithm (CLAUDIA) and the cloud microphysical properties algorithm (CAPCOM), which are used by the Second-generation GLobal Imager (SGLI) aboard the GCOM-C satellite, launched in December 2017. Also described are the preliminary results of cloud products’ validation. CLAUDIA was validated by comparing cloud fractions derived from satellite data against data from whole-sky images captured by ground-based fisheye cameras. User’s accuracy and producer’s accuracy were mostly high at around 90%, and the resulting overall accuracy was also high, ranging from 83 to 100% (average of all sites was 90.5%). CLAUDIA has proven to be sufficiently accurate to apply a cloud mask to measurements and meets the requirements for releasing data for SGLI cloud flag products (the minimum for a successful GCOM-C mission). CAPCOM was evaluated by comparing cloud properties obtained by SGLI products against data from MODIS collection 6 products (MOD06). This was done for both ocean and land in the low to middle latitudes (60° N–60° S) from August 22, 2018 to September 14, 2018. The comparison showed good correlation coefficients for cloud optical thickness, effective particle radius, and cloud-top temperature for water clouds: 0.88 (0.83), 0.92 (0.88), and 0.94 (0.92) for ocean (land), respectively. CAPCOM data for ice cloud optical thickness correlated well with data from MODIS products: 0.86 (ocean) and 0.82 (land).

Power dissipation is usually unavoidable in transistor channels due to the inelastic scattering of electrons. Here, Firdaus et al. propose a nanoscaled silicon electron-aspirator to remove this constraint, which shows enhanced current output by 3 times at 8 K without additional power supply.

With permafrost warming, the observed discharge of the Kolyma River in northeastern Siberia decreased between 1930s and 2000; however, the underlying mechanism is not well understood. To understand the hydrological changes in the Kolyma River, it is important to analyze the long-term hydrometeorological features, along with the changes in the active layer thickness. A coupled hydrological and biogeochemical model was used to analyze the hydrological changes due to permafrost warming during 1979–2012, and the simulated results were validated with satellite-based products and in situ observational records. The increase in the active layer thickness by permafrost warming suppressed the summer discharge contrary to the increased summer precipitation. This suggests that the increased terrestrial water storage anomaly (TWSA) contributed to increased evapotranspiration, which likely reduced soil water stress to plants. As soil freeze–thaw processes in permafrost areas serve as factors of climate memory, we identified a two-year lag between precipitation and evapotranspiration via TWSA. The present results will expand our understanding of future Arctic changes and can be applied to Arctic adaptation measures.

Abstract AAV vectors show promise for gene therapy; however, kidney gene transfer remains challenging. Here we conduct a barcode-seq-based comparison of 47 AAV capsids administered through different routes in mice, followed by individual validation. We find that local delivery of AAV-KP1, but not AAV9, via the renal vein or pelvis effectively transduces proximal tubules with minimal off-target liver transduction, while systemic AAV9, but not AAV-KP1, enhances proximal tubule and podocyte transduction in chronic kidney disease. We demonstrate that these contrasting observations are partly due to differences in their pharmacokinetics. Importantly, we show that renal pelvis injection overcomes pre-existing immunity, leading to robust and exclusive proximal tubule transduction, in non-human primates (NHPs). In addition, we highlight drastic differences in renal transduction profiles between mice and NHPs. Thus, this study provides mechanistic insights and underscores importance of context-dependent selection of AAV capsids to overcome challenges in gene delivery to the kidney.

Abstract Background Pembrolizumab plus cisplatin and 5-fluorouracil administered as first-line therapy for advanced esophageal cancer patients has shown a better objective response and survival than conventional chemotherapy with less severe hematological adverse events. The safety and efficacy of this regimen were evaluated in patients with T4b esophageal squamous cell carcinoma (ESCC). Methods Eight consecutive patients with T4b ESCC received this regimen according to KEYNOTE-590 as induction, and they were evaluated after 1–3 courses. The programmed death-ligand 1 (PD-L1) combined positive score (CPS) was also evaluated before chemotherapy. Efficacy for the primary lesion was evaluated by our original formula for the tumor reduction rate. Results The numbers of patients with partial response (PR), stable disease, and progressive disease (PD) were 5, 1, and 2, respectively. The tumor reduction rate ranged from 69 to 87% in PR patients, and all PR patients had relief from T4b. Two patients underwent conversion surgery with R0 resection. PD-L1 CPS was over 90 in 2 PR patients, but under 10 in 2 other PR patients. PD-L1 CPS was under 10 in PD patients. One patient had hyperprogression, resulting in an esophago-pulmonary fistula. Greater than grade 3 adverse events were bleeding gastric ulcer in one patient (12.5%), neutropenia without G-CSF in 3 patients (37.5%), and hypopotassemia in 1 patient (12.5%). No patient had febrile neutropenia. Conclusions Marked tumor reduction was confirmed in 62.5% of patients with pembrolizumab plus cisplatin and 5-fluorouracil with less adverse events. This regimen could be administered as induction chemotherapy for patients with T4b ESCC.