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This article explores Japanese perceptions of nuclear technology from 1945 to 1956, the early stage of the introduction of nuclear technology, by using discourses of the government and of antinuclear civil movements. It is based on the theoretical framework that discourses construct social perceptions of science and technology. For this purpose, statements such as official documents of the Japanese government and declarations made by the antinuclear movement were used as main resources of analysis. This article finds that various technological aspects influenced the formation of the Japanese nuclear technological system. In addition, the Japanese government tried to keep open the possibility of developing nuclear weapons. It tried to justify its ‘peaceful use of nuclear power’ by portraying itself as the sole victim of nuclear weapons while hiding its intention to develop nuclear weapons. Moreover, the nuclear safety myth was formed at the beginning of the introduction of nuclear technology. As a result, we can see that in Japan, the nuclear safety myth was growing from the beginning of the introduction of nuclear technology amid a dichotomous understanding of good and bad uses of nuclear power and the desire to enter an advanced state of science and technology.

To characterize and evaluate the estimation of oxygen saturation measured by a wrist-worn reflectance pulse oximeter during sleep.Ninety-seven adults with sleep disturbances were enrolled. Oxygen saturation was simultaneously measured using a reflectance pulse oximeter (Galaxy Watch 4 [GW4], Samsung, South Korea) and a transmittance pulse oximeter (polysomnography) as a reference. The performance of the device was evaluated using the root mean squared error (RMSE) and coverage rate. Additionally, GW4-derived oxygen desaturation index (ODI) was compared with the apnea-hypopnea index (AHI) derived from polysomnography.The GW4 had an overall RMSE of 2.3% and negligible bias of -0.2%. A Bland-Altman density plot showed good agreement between the GW4 and the reference pulse oximeter. RMSEs were 1.65 ± 0.57%, 1.76 ± 0.65%, 1.93 ± 0.54%, and 2.93 ± 1.71% for normal (n = 18), mild (n = 21), moderate (n = 23), and severe obstructive sleep apnea (n = 35), respectively. The data rejection rate was 26.5%, which was caused by fluctuations in contact pressure and the discarding of data less than 70% of saturation. A GW4-ODI ≥5/h had the highest ability to predict AHI ≥15/h with sensitivity, specificity, accuracy, and area under the curve of 89.7%, 64.1%, 79.4%, and 0.908, respectively.This study evaluated the estimation of oxygen saturation by the GW4 during sleep. This device complies with both Food and Drug Administration and International Organization for Standardization standards. Further improvements in the algorithms of wearable devices are required to obtain more accurate and reliable information about oxygen saturation measurements.

A nanostructured spiro-OMeTAD can be fabricated via nanoimprint soft lithography and realizes back-side nanostructured perovskite quantum dot solar cells showing improved photovoltaic performance due to the enhanced light absorption and photocurrent.

CsPbI3 perovskite quantum dots (CsPbI3-PQDs) have recently come into focus as a light-harvesting material that can act as a platform through which to combine the material advantages of both perovskites and QDs. However, the low cubic-phase stability of CsPbI3-PQDs in ambient conditions has been recognized as a factor that inhibits device stability. TiO2 nanoparticles are the most regularly used materials as an electron transport layer (ETL) in CsPbI3-PQD photovoltaics; however, we found that TiO2 can facilitate the cubic-phase degradation of CsPbI3-PQDs due to its vigorous photocatalytic activity. To address these issues, we have developed chloride-passivated SnO2 QDs (Cl@SnO2 QDs), which have low photocatalytic activity and few surface traps, to suppress the cubic-phase degradation of CsPbI3-PQDs. Given these advantages, the CsPbI3-PQD solar cells based on Cl@SnO2 ETLs show significantly improved device operational stability (under conditions of 50% relative humidity and 1-sun illumination), compared to those based on TiO2 ETLs. In addition, the Cl@SnO2-based devices showed improved open circuit voltage and photocurrent density, resulting in enhanced power conversion efficiency (PCE) up to 14.5% compared to that of TiO2-based control devices (PCE of 13.8%).

The power conversion efficiency of CsPbI

AgBiS2 nanocrystals (NCs) have emerged as attractive absorbers in eco-friendly photovoltaics because of their nontoxic components and high absorption coefficient. Native long-chain ligands of AgBiS...

Control over carrier type and doping levels in semiconductor materials is key for optoelectronic applications. In colloidal quantum dots (CQDs), these properties can be tuned by surface chemistry modification, but this has so far been accomplished at the expense of reduced surface passivation and compromised colloidal solubility; this has precluded the realization of advanced architectures such as CQD bulk homojunction solids. Here we introduce a cascade surface modification scheme that overcomes these limitations. This strategy provides control over doping and solubility and enables n-type and p-type CQD inks that are fully miscible in the same solvent with complete surface passivation. This enables the realization of homogeneous CQD bulk homojunction films that exhibit a 1.5 times increase in carrier diffusion length compared with the previous best CQD films. As a result, we demonstrate the highest power conversion efficiency (13.3%) reported among CQD solar cells., It is challenging to realize doping and surface passivation simultaneously in colloidal quantum dot inks. Here Choi et al. employ a cascade surface modification approach to solve the problem and obtain record high efficiency of 13.3% for bulk homojunction solar cells based on these inks.

BACKGROUND Obstructive sleep apnea (OSA) is a common sleep disorder characterized by repetitive upper airway obstruction during sleep, thereby resulting in oxygen desaturation, frequent arousals, and increased sympathetic activity. Wearable devices that measure peripheral oxygen saturation have been developed for the screening of OSA. OBJECTIVE This study aimed to validate and characterize the estimation function of oxygen saturation measured by wrist-worn reflectance pulse oximetry during sleep and to predict the derived OSA using the oxygen desaturation index (ODI). METHODS Oxygen saturation was simultaneously measured using reflectance pulse oximetry from the Samsung Galaxy Watch 4 series (SM-R890N, SM-R860N, Samsung Electronics Co.; GW4) and transmittance pulse oximetry from polysomnography as a reference (SpO2Ref). The performance was evaluated by the root mean squared error (RMSE) and coverage rate, and it was compared according to the apnea-hypopnea index (AHI). The GW4-ODI was used to predict moderate to severe OSA. RESULTS A total of 97 adults (44.4 ± 13.0 years; men 76.3%, women 23.7%) participated in this study. Depending on the AHI, participants were classified as either normal (n=18), mild (n=21), moderate (n=23), or severe OSA (n=35). Wrist-worn reflectance pulse oximetry showed an overall RMSE of 2.3% and negligible bias of -0.2%. A Bland-Altman density plot showed good agreement of oxygen saturation between GW4 and the reference pulse oximeter. RMSEs were 1.65 ± 0.57%, 1.76 ± 0.65%, 1.93 ± 0.54%, and 2.93 ± 1.71% for normal, mild, moderate, and severe OSA, respectively. GW4-ODI ≥5/h had the highest predictive ability for moderate to severe OSA with a sensitivity of 89.7%, a specificity of 64.1%, an accuracy of 79.4%, and an area under the curve of 0.908 (95% CI, 0.852–0.963). CONCLUSIONS GW4 was successfully validated for measuring oxygen saturation with reflectance pulse oximetry during sleep. This study demonstrates the feasibility of GW4 for screening moderate to severe OSA.

Neuroblastoma (NB) is a pediatric tumor of the peripheral nervous system. Approximately 80% of relapsed NB show RAS-MAPK pathway mutations that activate ERK, resulting in the promotion of cell proliferation and drug resistance. Ulixertinib, a first-in-class ERK-specific inhibitor, has shown promising antitumor activity in phase 1 clinical trials for advanced solid tumors. Here, we show that ulixertinib significantly and dose-dependently inhibits cell proliferation and colony formation in different NB cell lines, including PDX cells. Transcriptomic analysis revealed that ulixertinib extensively inhibits different oncogenic and neuronal developmental pathways, including EGFR, VEGF, WNT, MAPK, NGF, and NTRK1. The proteomic analysis further revealed that ulixertinib inhibits the cell cycle and promotes apoptosis in NB cells. Additionally, ulixertinib treatment significantly sensitized NB cells to the conventional chemotherapeutic agent doxorubicin. Furthermore, ulixertinib potently inhibited NB tumor growth and prolonged the overall survival of the treated mice in two different NB mice models. Our preclinical study demonstrates that ulixertinib, either as a single agent or in combination with current therapies, is a novel and practical therapeutic approach for NB.

We study the problem of computing a minimum-width annulus with outliers. Specifically, given a set of n points in the plane and an integer k with 1 ≤ k ≤ n , the problem asks to find a minimum-width annulus that contains at least n − k input points. The k excluded points are considered as outliers of the input points. In this paper, we are interested in particular in annuli of three different shapes: circular, square, and rectangular annuli. For the three cases, we present first and improved algorithms to the problem.

We consider the planar two-center problem for a convex polygon: given a convex polygon in the plane, find two congruent disks of minimum radius whose union contains the polygon. We present an \(O(n\log n)\)-time algorithm for the two-center problem for a convex polygon, where n is the number of vertices of the polygon. This improves upon the previous best algorithm for the problem.

We consider the planar Euclidean two-center problem in which given $n$ points in the plane we are to find two congruent disks of the smallest radius covering the points. We present a deterministic $O(n \log n)$-time algorithm for the case that the centers of the two optimal disks are close to each other, that is, the overlap of the two optimal disks is a constant fraction of the disk area. We also present a deterministic $O(n\log n)$-time algorithm for the case that the input points are in convex position. Both results improve the previous best $O(n\log n\log\log n)$ bound on the problems., Comment: 13 pages, 6 figures

Efficient infrared (IR) optoelectronic devices, crucial for emerging sensing applications and also for solar energy harvesting, demand high-conductivity IR-transparent electrodes. Here we present a new strategy, one based on oxide/metal/oxide multilayers, that enables highly transparent IR electrodes. Symmetry breaking in the oxide stack leads to broad and high transmittance from visible to IR wavelengths, while a low refractive index doped oxide as a front layer boosts IR transmittance. The combination of doped oxide and ultrathin metal film allows for low sheet resistance while maintaining IR transparency. We engineer the IR microcavity effect using the asymmetric multilayer approach to tailor the distribution of incident radiation to maximize IR absorption in the colloidal quantum dot (CQD) layer. As a result, the absorption-enhanced IR CQD solar cells exhibit a photoelectric conversion efficiency of 70% at a wavelength of 1.25 μm, i.e., well within the spectral range in which silicon is blind.

The electrochemical carbon dioxide reduction reaction (CO2RR) produces diverse chemical species. Cu clusters with a judiciously controlled surface coordination number (CN) provide active sites that simultaneously optimize selectivity, activity, and efficiency for CO2RR. Here we report a strategy involving metal–organic framework (MOF)-regulated Cu cluster formation that shifts CO2 electroreduction toward multiple-carbon product generation. Specifically, we promoted undercoordinated sites during the formation of Cu clusters by controlling the structure of the Cu dimer, the precursor for Cu clusters. We distorted the symmetric paddle-wheel Cu dimer secondary building block of HKUST-1 to an asymmetric motif by separating adjacent benzene tricarboxylate moieties using thermal treatment. By varying materials processing conditions, we modulated the asymmetric local atomic structure, oxidation state and bonding strain of Cu dimers. Using electron paramagnetic resonance (EPR) and in situ X-ray absorption spectros...

We synthesized freestanding doubly open-ended TiO2 nanotubes (DNT) film and compared their photocatalytic activity and durability during the repeated degradation cycles of volatile organic compounds (VOCs) with those of TiO2 nanotubes (TNT) film. DNT exhibited higher activity and durability for the photocatalytic degradation of gaseous acetaldehyde and toluene than TNT. The doubly open-ended structure of DNT allows O2 molecules to be easily supplied to the active sites, which increases not only the intrinsic photocatalytic activity but also the resistance to catalyst deactivation. The freestanding DNT film was additionally loaded with TiO2 nanoparticles (NP@DNT) in the inner wall to further increase the activity for VOC degradation. The photocatalytic activity of NP@DNT was higher than bare DNT and bare TNT by 1.3 and 1.8 times, respectively. Unlike the case of DNT, the TiO2 nanoparticles loaded TNT (NP@TNT) exhibited a lower activity than bare TNT, probably because the TiO2 nanoparticles blocked the TNT channels with hindering the mass transfer of O2 and VOC molecules. DNT with doubly open-ended structure serves as a versatile platform of fabricating nanostructured photocatalysts with maintaining the open channel structure that facilitates the mass transfer of O2 and VOC molecules.

Colloidal quantum dots (CQDs) are promising materials for photovoltaic (PV) applications owing to their size-tunable bandgap and solution processing. However, reports on CQD PV stability have been limited so far to storage in the dark; or operation illuminated, but under an inert atmosphere. CQD PV devices that are stable under continuous operation in air have yet to be demonstrated-a limitation that is shown here to arise due to rapid oxidation of both CQDs and surface passivation. Here, a stable CQD PV device under continuous operation in air is demonstrated by introducing additional potassium iodide (KI) on the CQD surface that acts as a shielding layer and thus stands in the way of oxidation of the CQD surface. The devices (unencapsulated) retain >80% of their initial efficiency following 300 h of continuous operation in air, whereas CQD PV devices without KI lose the amount of performance within just 21 h. KI shielding also provides improved surface passivation and, as a result, a higher power conversion efficiency (PCE) of 12.6% compared with 11.4% for control devices.