New Triclinic Perovskite-Type Oxide Ba5CaFe4O12 for Low-Temperature Operated Chemical Looping Air Separation.

We present the discovery of Ba5CaFe4O12, a new iron-based oxide with remarkable properties as a low-temperature driven oxygen storage material (OSM). OSMs, which exhibit selective and rapid oxygen intake and release capabilities, have attracted considerable attention in chemical looping technologies. Specifically, chemical looping air separation (CLAS) has the potential to revolutionize oxygen production as it is one of the most crucial industrial gases. However, the challenge lies in utilizing OSMs for energy-efficient CLAS at lower temperatures. Ba5CaFe4O12, a cost-competitive material, possesses an unprecedented 5-fold perovskite-type A5B5O15-δ structure, where both Fe and Ca occupy the B sites. This distinctive structure enables excellent oxygen intake/release properties below 400 °C. This oxide demonstrates the theoretical daily oxygen production rate of 2.41 mO23 kgOSM-1 at 370 °C, surpassing the performance of the previously reported material, Sr0.76Ca0.24FeO3-δ (0.81 mO23 kgOSM-1 at 550 °C). This discovery holds great potential for reducing costs and enhancing the energy efficiency in CLAS.

Tunable Oxygen Intake/Release Characteristics of Brownmillerite-Type Ca2AlMnO5+δ Involving Atomic Defect Formations.

The oxygen intake/release characteristics were systematically studied for Ca2AlMnO5+δ samples synthesized under precisely controlled oxygen pressures. Both the oxygen storage capacity (OSC) and operating temperature were systematically lowered as the oxygen pressure in the firing atmosphere increased. Notably, the sample fired under a 1% O2 atmosphere exhibited sufficiently large OSC and superior oxygen intake/release kinetics to the pristine sample synthesized in an anaerobic condition. The high-angle annular dark-field scanning TEM observation revealed that the samples contain defects in their atomic arrangement when fired in oxygen-rich atmospheres. This result indicates that the oxygen intake/release characteristics of Ca2AlMnO5+δ are sensitive to the synthesis condition and widely tunable even without chemical substitutions.

Electrochemical Crystal Growth of Titanium Oxyfluorides-A Strategy for Development of Electron-Doped Materials.

We report on the growth of single crystals of an electron-doped titanium oxyfluoride, Li2Ti(O,F)3, employing high-temperature electrolysis of TiO2 with a eutectic Li2MoO4-LiF melt. Greenish octahedral-shaped crystals (∼30 µm in size) with a cubic rocksalt-type structure were successfully obtained by precisely tuning the applied voltage. The temperature-dependent magnetic susceptibility data revealed a paramagnetic behavior at low temperatures, ensuring the presence of Ti3+ ions (mean valence number of +3.78; F/Ti ∼ 0.15). The crystals exhibited clear visible-light absorption and produced H2 from water in the presence of a sacrificial reagent under UV-light irradiation. Li2Ti(O,F)3 more efficiently produced H2 compared with a nondoped oxyfluoride Li5Ti2O6F, likely due to the doped electrons for the former. This work highlights a promising electrochemical approach toward growing electron-doped oxyfluoride crystals.

Physical Parameters, Use of Specific Medical Treatments, Nursing Levels, and Activities of Daily Living Are Potential Indicators for Forgoing Maintenance Hemodialysis.

Maintenance hemodialysis (HD) therapy is essential for survival in patients with end-stage renal disease (ESRD); however, HD can also be life-threatening in the final stages of ESRD. Currently, no clear indicators and/or biomarkers exist regarding when HD should be forgone. In the present study, we examined temporal changes in multiple clinical parameters, including biochemical data, physical data, the use of specific medical treatments, nursing care levels, and the activities of daily living (ADL) in 47 ESRD patients who underwent maintenance HD and who died in our hospital. We also investigated the status of informed consents regarding the forgoing of HD in these patients. We found that while biochemical parameters were unaltered, physical parameters such as consciousness levels and blood pressure gradually deteriorated during hospitalization. The use of the following specific medical treatments significantly increased over time: vasopressor use, O2 inhalation, and ventilator use. The need for nursing care increased and the ADL levels decreased toward the time of death. Medical doctors gave information regarding forgoing HD to patients and/or their family/relatives in 55% of cases, obtained agreement to forego HD in 45% of cases, and HD was actually foregone in 38% of cases. Most clinical parameters were not significantly different between the patients whose HD sessions were forgone versus those in whom HD was continued, indicating that HD was foregone in the very last stages of life. The results suggest that physical parameters, the use of specific medical treatments, the levels of nursing care, and ADL are potential indicators for forgoing HD in the final stages of ESRD.

Reperfusion of the choriocapillaris observed using optical coherence tomography angiography in hypertensive choroidopathy.

PURPOSE: Optical coherence tomography angiography (OCTA) can visualize the vascular status of the choriocapillaris noninvasively and separately from the other vascular beds. We describe focal ischemia in the choriocapillaris and reperfusion of the area in hypertensive choroidopathy using en-face OCTA. CASE: A 32-year-old woman diagnosed with pregnancy-induced hypertension presented with acute anorthopia in the right eye after delivery via Caesarian section. Fundus examination showed an Elschnig's spot and serous retinal detachment (SRD) in the inferior perifoveal region. Early-phase fluorescein angiography and indocyanine green angiography images showed focally delayed choroidal perfusion, i.e., regional absence of choroidal flush. OCTA also showed a focal dark area in a slab of the choriocapillaris corresponding to the angiographic observation. After oral antihypertensive treatment, the dark area on the OCTA image of the choriocapillaris resolved over time in association with the resolving SRD. CONCLUSION: En-face OCTA is a useful technology to follow noninvasively the circulatory status of the choriocapillaris in hypertensive choroidopathy.

Stress and coping styles in Japanese nursing students.

The objective of this investigation was to examine the stress and coping styles in Japanese nursing students. The principal measures of the stress and coping styles were the General Health Questionnaire (GHQ)-12 and Brief Coping Orientations to Problems Experienced scale. In a cross-sectional analysis, 1324 students completed the anonymous self-administered questionnaires including the scales earlier. Feeling stress, living with family, not eating breakfast every day, having no regular exercise and poor sleep were associated with GHQ responder (psychological distressed group). The most commonly reported source of stress was taking examinations, followed by relationships with friends, engaging in clinical practice and presenting reports. The three most common coping styles adopted by the nursing students were acceptance, self-distraction and using instrumental support. By logistic regression analysis of coping styles with GHQ responder, self-blame, active coping, acceptance and behavioural disengagement were highly associated with GHQ responder. The nursing school educators as well as students should be aware of stress management strategies (e.g. using active coping and avoiding self-blame) that may help prevent depression.