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A woman in her late 70 s was diagnosed with liver injury at a health examination. Despite treatment with ursodeoxycholic acid at a nearby hospital, her transaminase levels elevated in two peaks. She was transferred to our hospital 77 days after the health examination. She weighed 42 kg and had a low body mass index of 19.8 kg/m

We report on boron-related defects in the low-doped n-type (nitrogen-doped) 4H-SiC semitransparent Schottky barrier diodes (SBDs) studied by minority carrier transient spectroscopy (MCTS). An unknown concentration of boron was introduced during chemical vapor deposition (CVD) crystal growth. Boron incorporation was found to lead to the appearance of at least two boron-related deep-level defects, namely, shallow (B) and deep boron (D-center), with concentrations as high as 1 × 1015 cm−3. Even though the boron concentration exceeded the nitrogen doping concentration by almost an order of magnitude, the steady-state electrical characteristics of the n-type 4H-SiC SBDs did not deteriorate.

Negatively charged silicon vacancy (VSi−) defects in silicon carbide are expected to be used for magnetic sensors under harsh environments, such as space and underground due to their structural stability and potential for high-fidelity spin manipulation at high temperatures. To realize VSi− based magnetic sensors operating at high temperatures, the temperature dependence of optically detected magnetic resonance (ODMR) in the ground states of VSi− defects, which is the basic principle of magnetic sensing, should be systematically understood. In this work, we demonstrate the potential of VSi− magnetic sensors up to at least 591 K by showing the ODMR spectra with different temperatures. Furthermore, the resonance frequency of the ground level was independent of temperature, indicating the potential for calibration-free magnetic sensors in temperature-varying environments. We also characterize the concentration of VSi− defects formed by electron irradiation and clarify the relationship of magnetic sensing sensitivity to VSi− concentration and find that the sensing sensitivity increases linearly with VSi− concentration up to at least 6.0 × 1016 cm−3. The magnetic sensitivity at a temperature above 549 K was reduced by half as compared to that at 300 K. The results pave the way for the use of a highly sensitive VSi−-based magnetic sensor under harsh environments.

Silicon vacancies (Vsi) in silicon carbide (SiC) have attracted attention because they can be used for quantum sensors (F. Fuchs et al., Nat. Com. 6: 7578 (2015)). We aim to develop Vsi magnetic sensors operating at high temperatures because of its structural stability. However, change with temperatures, especially high temperature, in optically detected magnetic resonance (ODMR) in the ground state of Vsi, which is the basic principle of magnetic sensing, is less well understood. Here, we report the change in ODMR spectra of Vsi with different temperatures., Defects in solids for quantum technologies(DSQT)

We examined 171 patients with novel coronavirus disease 2019 (COVID-19) with liver injury in the respiratory failure groups and the nonrespiratory failure groups and investigated 41 patients with moderate II COVID-19 with respiratory failure who received dexamethasone (Dex) monotherapy in the liver injury group and the nonliver injury group at the time before treatment. The respiratory failure group had 64% more liver damage than the nonrespiratory failure group, was older, had more men, and had significantly more complications from lifestyle-related diseases such as hypertension and diabetes. Obesity was more common in the liver injury group prior to Dex monotherapy, and the liver CT value was significantly lower than in the nonliver injury group. Liver injury worsened in 41% of patients after Dex monotherapy, but there was no significant difference in the frequency before Dex monotherapy between the liver injury group and the nonliver injury group, and the degree of liver injury was mild in all cases, improving in 38% of the liver injury group. Dex monotherapy was a safe treatment for moderate II COVID-19, which frequently resulted in liver injury.

炭化ケイ素中のシリコン空孔(Vsi)は、磁場や温度を高感度に検出できる「量子センサ」としての応用が期待されている。Vsiは高エネルギー電子線照射によって形成することができ、センサ感度はVsiの数(濃度)に依存するが、実用化のためにはVsi濃度の定量が重要となる。また、電子線照射によってデコヒーレンスの原因となる不要な照射欠陥も同時に形成されるため、その影響を明らかにするとともに低減する手法を確立する必要がある。本研究では、電子スピン共鳴(ESR)測定より、電子線照射量に対するVsi形成濃度を定量化するとともに、磁気センシングの基本原理である光検出磁気共鳴(ODMR)スペクトルの変化を調べ、照射欠陥の影響について検討した。高純度半絶縁性4H-SiC基板に2 MeV電子線を最大3.0×1018 cm-2まで照射し、Vsiを形成した。その後、真空中600℃で30分間の熱処理を行い、Vsi以外の不要な欠陥を低減した(Y. Chiba et al., Mater. Sci. Forum 1004, 337 (2020).) 。Fig.1(a)は3.0×10^18 cm-2照射した試料の室温でのESRスペクトルであり、(b)は室温ESR測定により同定した電子線照射量に対するVsi濃度の変化を示している。Vsi起因のESR信号は電子線照射量に対し比例関係にあると考えVsi収率を算出すると、未熱処理試料では5.7×10^(-3) cm^(-1) 、熱処理試料では3.6×10^(-3) cm^(-1) となった。講演では、Vsi濃度に対するODMRスペクトル（磁気感度）の変化について議論する。, 第69回応用物理学会春季学術講演会

炭化ケイ素(SiC)中のシリコン空孔(VSi)は磁気や温度を高感度に検出する「量子センサ」として注目されており、特に、VSiは高温下でも安定して存在するため、宇宙や地底といった厳環境に対応できる高感度磁気センサなどへの応用が期待できる。しかし、磁気センシングの基本原理となる光検出磁気共鳴(ODMR)現象の高温下での振る舞いは明らかになっていない。また、VSiは高エネルギー電子線照射によって形成するが、デコヒーレンスの要因となる不要な欠陥も同時に形成され、その影響も考慮しなければならない。そこで本研究では、ODMR スペクトルに対するVSi形成量及び測定温度依存性を系統的に調査した。さらに、磁気感度評価を行い、シリコン空孔量子センサの実現に向けた新たな知見を示した。, 第 11 回 半導体・超電導量子コテレンスと量子情報参加の為

Negatively charged boron vacancy (V B –) in hexagonal boron nitride has attracted attention as a promising spin defect for quantum sensing applications. Hence, a fabrication method for generation of V B – with superior spin properties would be desirable. In this study, we demonstrated V B – formation by two thermal treatment methods. Both methods improve the signal-to-noise ratio of optically detected magnetic resonance signal by a factor of 4. Furthermore, a zero-field splitting parameter E which reflects crystal distortion after irradiation significantly reduces for irradiation above 650 °C. These findings indicate that thermal treatment is an effective method for a V B – based quantum sensor.

A 66-year-old man, who had undergone plasma exchange 30 years previously in Egypt for the treatment of falciparum malaria, was referred to our hospital for treatment of chronic hepatitis C (HCV). An analysis of the 655-nucleotide 5'-untranslated region-core region sequence revealed infection with HCV subtype 1g. A phylogenetic analysis of the full-length HCV genome confirmed that the patient's HCV was subtype 1g, which was the first case identified in Japan. Although his HCV possessed several naturally occurring resistance-associated substitutions in the nonstructural (NS) 3 and NS5A regions, he was successfully treated by combination therapy with glecaprevir/pibrentasvir.

Silicon vacancy (VSi) centers in silicon carbide have attracted attention because of their potential applications to quantum sensors (high-sensitivity magnetic field and temperature sensors). VSi centers are also expected to be used for magnetic sensors under harsh environments such as space and undergrounds, since they have structural stability and the potential of high-fidelity spin manipulation at high temperatures. To realize VSi based magnetic sensors operating at high temperature, understanding of optically detected magnetic resonance (ODMR) in the ground states of VSi centers, which is the basic principle of magnetic sensing, is crucial. In particular, the effects of temperature on the ODMR spectra are less well understood. Here, we demonstrate the potential of VSi magnetic sensors at high temperatures by showing the ODMR spectra with different temperatures. We also systematically investigate the effects of high energy electron irradiations on the ODMR spectra of formed VSi centers. The concentration of VSi centers increases with increasing electron irradiation dose, resulting in the enhancement of sensitivity, but the increase of undesired defects which might cause decoherence is also considered. Hence, the effects of electron irradiation dose should be clarified to obtain better sensitivity of VSi based magnetic sensors., The 4th International Forum on Quantum Metrology and Sensing

Direct energy conversion has been investigated using Ni/SiC Schottky junctions with the irradiation of monochromatized synchrotron x rays mimicking the gamma rays of 237Np (30 keV) and 241Am (60 keV). Through current–voltage measurements, electrical energies were obtained for both types of gamma rays. The energy conversion efficiencies based on absorbed energy were found to be ∼1.6%, which is comparable to other previously described semiconducting systems. This result raises the prospect of energy recovery from nuclear wastes utilizing the present system, judging from the radiation tolerant nature of SiC. Additionally, we found different conversion efficiencies between the two samples during the same process. This could be explained using hard x-ray photoelectron spectroscopy and secondary ion mass spectroscopy measurements, suggesting the creation of Ni–Si compounds at the interface in the sample with poor performance. Hence, such combined measurements are useful to provide data that electrical measurements cannot provide us.