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Designing new materials with desired properties is a complex and time-consuming process. One of the most challenging factors of the design process is the huge search space of possible materials. Machine learning methods such as [Formula: see text]-nearest neighbors, support vector machine (SVM) and artificial neural network (ANN) can contribute to this process by predicting materials properties accurately. Properties of multi-principal element alloys (MPEAs) highly depend on alloys’ phase. Thus, accurate prediction of the alloy’s phase is important to narrow down the search space. In this paper, we propose a solution of employing SVM method with hyperparameters tuning and the use of weighted values for prediction of the alloy’s phase. Using the dataset consisting of the experimental results of 118 MPEAs, our solution achieves a cross-validation accuracy of 90.2%. We confirm the superiority of this score over the performance of ANN statistically. On the other dataset containing 401 MPEAs, our SVM model is comparable to ANN and exhibits 70.6% cross-validation accuracy. We also found that additional variables, including average melting temperature and standard deviation of melting temperature, increase prediction accuracy by 3.34% in the best case.

Aim: Stroke is well known to lead to hypertension; nevertheless, the role of vascular function in hypertension remains unclear. In this study, we aimed to clarify the mechanism underlying increased arterial stiffness following stroke. Methods: The cardio-ankle vascular index (CAVI) was measured in five New Zealand White rabbits. Under general anesthesia, intracranial pressure (ICP) was increased by injecting saline (15 mL) into the cisterna magna. ICP was monitored using a catheter inserted into the subarachnoid space via right frontal bone craniotomy. Blood pressure (BP), CAVI, and common carotid flow (CCF) were evaluated, and the responses of these parameters to increased ICP were analyzed. Results: Saline injection into the cisterna magna increased the ICP by over 20 mmHg. Both BP and CAVI increased from 63.2±4.84 to 128.8±14.68 mmHg and from 4.02±0.28 to 4.9±0.53, respectively. Similarly, BP and CCF increased. When hexamethonium was administered before the increase in ICP, the increase in BP (132.2±9.41 mmHg with 10 mg/kg hexamethonium vs. 105.6±11.01 mmHg with 100 mg/kg hexamethonium) and CAVI (5.02±0.64 with 10 mg/kg hexamethonium vs. 4.82±0.42 with 100 mg/kg hexamethonium) were suppressed in a dose-dependent manner. Conclusion: Increased ICP causes an increase in BP and CAVI, suggesting that enhanced stiffness of the muscular arteries contributes to high BP. Blocking the autonomic nervous system with hexamethonium suppresses the increase in BP and CAVI, indicating that these increases are mediated by activation of the autonomic nervous system.

Organo-halide perovskite solar cells (PSCs) are lightweight and low cost, and they offer high power conversion efficiencies. PSCs have proven to be useful in terrestrial applications. In addition, they are particularly attractive for space applications because they can offer a higher radiation tolerance than GaAs and Si solar cells. This paper evaluates the damage coefficient for minority carrier diffusion length KL of perovskite crystals after 1 MeV electron irradiation by time-resolved photoluminescence measurements to investigate the reason for their high radiation tolerance. Results show that perovskite crystals have a lower damage coefficient KL than that of InP crystals with a high radiation tolerance. On the other hand, first-principles calculations indicate that the displacement energy of perovskite crystals is as low as that of Si, which does not have a high radiation tolerance. The present results suggest that the annealing effect occurs for PSCs at room temperature.

Koji Takahashi,1 Tomoyuki Yamamoto,1 Kohji Shirai2 1Fukuda Denshi Co., Ltd., Tokyo, Japan; 2Department of Internal Medicine, Mihama Hospital, Chiba, JapanCorrespondence: Tomoyuki Yamamoto, Email tomoyuki.yamamoto@fukuda.co.jp

Numerous attempts have been made to improve the oxidation resistance and electrical conductivity of the interconnectors in solid oxide fuel cells. A Co–W alloy coating on ferritic stainless steel has attracted attention because the Co–W oxide layer formed by the oxidation treatment of the Co–W alloy coating has proven effective in reducing the outward diffusion of Cr and improving oxidation resistance. This study was designed to elucidate the diffusion behavior of elements and the barrier mechanism of the CoWO4 layer. After oxidation in air at 750°C, a dense, multilayered oxide formed, comprising (from the stainless steel substrate to the outer layer) Cr2O3, (Cr,Fe,Co)3O4, CoWO4, (Co,Fe)3O4, and Co3O4 layers. The CoWO4 layer and neighboring oxide layers were carefully analyzed by scanning electron microscopy and transmission electron microscopy with electron energy-loss spectroscopy, confirming the absence of trivalent cations (Co3+, Fe3+, and Cr3+) and the presence of Fe2+ ions in the CoWO4 layer; thus, CoWO4 functions as a selective diffusion barrier to trivalent cations, as hypothesized. The Cr-containing oxide layer grows based on the reaction between the metallic cations from the substrate and the inward-diffusing oxide ions, whereas Fe and Co can diffuse outward through CoWO4 as Fe2+ and Co2+ ions.

Arterial stiffness is a good predictor of cardiovascular events. As a substitute for elastic modulus representing stiffness, pulse wave velocity (PWV) has been used for over a century as it is easy to measure ; however, PWV is known to essentially depend on blood pressure at the time of measurement. The cardio-ankle vascular index (CAVI) is a relatively new index of global arterial stiffness of the origin of the aorta to the ankle arteries. The characteristic feature is its independency from blood pressure at the measuring time. Recently, a variant index CAVI0 was proposed, which was claimed to be a more accurate arterial stiffness index than CAVI, considering independency from blood pressure. The purpose of this review is to evaluate the properties of CAVI more precisely by comparing with CAVI0, and to confirm the true meaning of CAVI as an index of arterial stiffness. First, the properties of PWV depending on the blood pressure and the variation of PWV values in the cardiac cycle were analyzed. Then, we attempted to clarify the point at which the PWV, adopted in CAVI or in CAVI0, was measured in cardiac cycle. A comprehensive comparison of the clinical data of CAVI and CAVI0 showed that CAVI is more appropriate than CAVI0. In conclusion, CAVI is reconfirmed to be a reliable and useful index of blood pressure-independent arterial stiffness composed of both organic and functional stiffness.

Aim: The cardio-ankle vascular index (CAVI) represents the blood pressure-independent arterial stiffness from the origin of the aorta to the ankle. CAVI0 has been proposed as a variant index. We aimed to clarify the difference between CAVI and CAVI0 among large populations, and to explore reasons of the difference. Methods: The subjects were 5,293 Japanese healthy and 3,338 hypertensive people. Simple and multiple regression analyses were performed using age, sex, body mass index, systolic, and diastolic blood pressure (Pd) as variables. Sub-group analysis was performed by sex and age. The CAVI values with and without adjustment by reference pressure were also compared. Results: CAVI had a positive correlation with Pd, while CAVI0 had a negative correlation with Pd in the healthy population. The CAVI values of the hypertensive group were higher than those of healthy group in both men and women, but the CAVI0 values in women of the hypertensive group in the 30–39 age group was significantly lower than that of the corresponding healthy group. Differences of CAVI values with or without modification using the reference pressure were 1.09% ± 1.38% for the healthy group and 3.68% ± 1.66% for the hypertensive group. Conclusion: CAVI showed the expected values, but CAVI0 showed inexplicable results in the healthy and hypertensive populations. The differences were due to the strong dependency of CAVI0 on Pd. Differences of CAVI values with or without reference pressure were negligible. These results indicate that CAVI obtained by the VaSera system is appropriate, but CAVI0 is not.

Designing new materials with desired properties is a complex and time-consuming process. One of the challenging factors of the design process is the huge search space of possible materials. Machine learning methods such as k-nearest neighbours, support vector machine (SVM) and artificial neural network (ANN) can contribute to this process by predicting materials properties accurately. Properties of multi-principal element alloys (MPEAs) highly depend on alloys’ phase. Thus, accurate prediction of the alloy’s phase is important to narrow down the search space. In this paper, we propose a solution of employing support vector machine method with hyperparameters tuning and the use of weight values for prediction of the alloy’s phase. Using the dataset consisting of the experimental results of 118 MPEAs, our solution achieves the cross-validation accuracy of 90.2%. We confirm the superiority of this score over the performance of ANN statistically. On the other dataset containing 401 MPEAs, our SVM model is comparable to ANN and exhibits 70.6% cross-validation accuracy.

The crystallization behavior of a newly developed polyvinyl alcohol with 1,2-diol side-chains (DPVA) was investigated for different 1,2-diol side-chain, magnesium acetate, and sodium acetate contents. Crystallization by stepwise cooling, isothermal and non-isothermal crystallization (the actual cooling process in melt molding) experiments were conducted. Upon crystallization analysis by stepwise cooling, the end surface energy of DPVA increased as the 1,2-diol side-chain content was increased. The isothermal crystallization process exhibited longer half crystallization times at high 1,2-diol side-chain and magnesium acetate contents. Upon Kissinger analysis of the non-isothermal crystallization results, the effect of the acetate salts was found to be smaller than that for isothermal crystallization, while the smaller number of repeating units in the lamellar structure, reflecting a higher side-chain 1,2-diol content, resulted in a smaller activation energy for DPVA crystallization. In addition, analyses by the Ozawa method and the Kissinger Plot suggested possible changes in the mode and dimension of the crystal growth of DPVA.

Accepted: 2017-03-27, 資料番号: SA1170259000

Co-doped CeO2 fabricated using the conventional solid-state reaction method demonstrates ferromagnetism at room temperature (RT). To investigate the origin of ferromagnetism at RT, powder X-ray diffraction analysis is first performed, in which pattern changes due to Co doping are not indicated. Subsequently, local environment analysis is carried out using X-ray absorption near-edge structure (XANES) measurements at the Co K-edge, demonstrating the metallic valence state of Co. Hence, it is confirmed that Co exists as nanosized small particles in CeO2, which demonstrates ferromagnetism at RT.

The local environment of Mn4+ ions in CaAl12O19 has been studied by electron spin resonance (ESR) measurements and by spin-polarized first principles calculations within a density functional theory to determine the site that is occupied by the Mn4+ ion when substituted for the Al3+ ion in CaAl12O19. There are three crystallographically inequivalent octahedral sites available for the Mn4+ ion in the CaAl12O19 lattice. Crystal field calculations of the Mn4+ energy levels for the preferred site were performed and shown to be in good agreement with the experimental spectroscopic data. ESR measurements confirmed the tetravalent oxidation state of Mn ion and showed that the local environment of the Mn ion was independent of the Mn4+ concentration in CaAl12O19. The ESR measurement also suggested the multiple site occupation by the Mn4+ ion in CaAl12O19. Additionally, the optimum concentration of Mn4+ in CaAl12O19 that produced the brightest phosphor was determined.

Asymmetric catalytic activities of various organocatalysts bearing double hydrogen-bonding donor units showing different pK a values were examined for direct aldol reactions of cyclohexanone with aromatic aldehydes. Organocatalyst with motif exhibiting the highest acidity resulted in the corresponding aldol products with the highest enantioselectivity. A good correlation has been observed between the asymmetric catalytic activity for direct aldol reactions and acidities of double hydrogen-bonding donating units.

Aim The effect of nitroglycerin on proper arterial stiffness of the arterial tree has not been fully clarified. The cardio-ankle vascular index (CAVI), which is an application of the stiffness parameter β theory on the arterial tree from the origin of the aorta to the ankle, was developed recently. Furthermore, the stiffness of the aorta (heart-thigh β (htBeta)) and of the femoral-tibial arteries (thigh to ankle β (taBeta)) could be monitored by applying the same theory. The effects of nitroglycerin on CAVI, htBeta, and taBeta were studied comparing the values of healthy people and those of arteriosclerotic patients. Methods The subjects were healthy people (CAVI ＜7.5, n=25) and arteriosclerotic patients (CAVI ＞9, n=25). Nitroglycerin (0.3 mg) was administrated sublingually, and various arterial stiffness indices were measured at one-minute intervals for a period of 20 minutes using Vasera VS-1500 (Fukuda Denshi, Tokyo). Results After the administration of nitroglycerin in healthy people, CAVI decreased significantly after 5 min. [from 6.76(6.32-7.27) to 5.50(4.70-6.21), P＜0.05], and recovered after 15 min. htBeta [from 5.10(4.76-5.76) to 3.96(3.35-4.79), P＜0.05], and taBeta [from 14.41(10.80-16.33) to 10.72 (9.19-13.01), P＜0.05] also decreased significantly. In arteriosclerotic patients, CAVI decreased after 5 min. [from 10.47(9.67-11.29) to 9.71(8.74-10.57), P＜0.05] and recovered after 15 min. htBeta did not significantly change [from 12.00(11.46-13.21) to 11.81(10.14-13.83), ns], but taBeta decreased significantly [from 18.55(12.93-23.42) to 12.37(9.68-16.99), P＜0.05]. Conclusion These results indicate that a nitroglycerin-induced decrease of arterial stiffness is more prominent in muscular arteries than in elastic arteries, and this effect was preserved much more prominently in arteriosclerotic patients than in healthy people.

The cardio-ankle vascular index (CAVI) represents the blood pressure-independent arterial stiffness from the origin of the aorta to the ankle. CAVIThe subjects were 5,293 Japanese healthy and 3,338 hypertensive people. Simple and multiple regression analyses were performed using age, sex, body mass index, systolic, and diastolic blood pressure (Pd) as variables. Sub-group analysis was performed by sex and age. The CAVI values with and without adjustment by reference pressure were also compared.CAVI had a positive correlation with Pd, while CAVICAVI showed the expected values, but CAVI

Development of a new electricity generation techniques is one of the most relevant tasks, especially nowadays under conditions of extreme growth in energy consumption. The exothermic heterogeneous electrochemical energy conversion to the electric energy through interaction of the ZrO2 based nanopowder system with atmospheric moisture is one of the ways of electric energy obtaining. The questions of conversion into the electric form of the energy of water molecules adsorption in 3 mol% Y2O3 doped ZrO2 nanopowder systems were investigated using the density functional theory calculations. The density functional theory calculations has been realized as in the Kohn-Sham formulation, where the exchange- correlation potential is approximated by a functional of the electronic density. The electronic density, total energy and band structure calculations are carried out using the all-electron, full potential, linear augmented plane wave method of the electronic density and related approximations, i.e. the local density, the generalized gradient and their hybrid approximations.

Numerous attempts have been made to improve the oxidation resistance and electrical conductivity of the interconnectors in solid oxide fuel cells. A Co-W alloy coating on ferritic stainless steel has attracted attention because the Co-W oxide layer formed by the oxidation treatment of the Co-W alloy coating has proven effective in reducing the outward diffusion of Cr and improving oxidation resistance. This study was designed to elucidate the formation kinetics and diffusion barrier mechanism of the Co-W coating. After oxidation in air at 750 °C, a dense, multilayered oxide formed, comprising (from the stainless steel substrate to the outer layer) Cr oxide, Cr-Fe-Co oxide, Co-W oxide, Co-Fe oxide, and Co oxide layers. The CoWO4 layer and neighboring oxide layers were carefully analyzed by scanning electron microscopy and transmission electron microscopy, which revealed that the innermost Cr2O3 layer grows via the reaction between Cr in the substrate and inward-diffusing oxygen, whereas outward diffusion of Fe and Co is involved in the formation and growth of (Co,Fe)3O4 and Co3O4. Analysis by electron energy-loss spectroscopy confirmed the absence of trivalent cations (Co3+, Fe3+, and Cr3+) and the presence of Fe2+ ions in the CoWO4 layer; thus, CoWO4 functions as a selective diffusion barrier to trivalent cations as hypothesized.

The first-principle calculations of the structural and electronic properties for a series of the Mn4+ doped A2SiF6 (A = K, Rb, Cs) phosphors within a density functional theory are performed to investigate influence of the first cation on the crystal field strength 10Dq and energy of the Mn4+ 2E→4A2 red emission transition. The structural changes due to an inclusion of the Mn4+ ions into A2SiF6 hosts are studied in detail here. The obtained results show that the shorter Mn–F bond length leads to higher emission energy of 2E→4A2 transition and 10Dq value. The emission energy for 2E→4A2 transition and 10Dq parameter of the Mn4+ doped A2SiF6 have been estimated using different functionals, such as conventional electron-electron correlation functional, generalized gradient approximation and local density approximation, the Hubbard type correction, i.e., DFT + U method, to the Mn 3d electrons, to identify most suitable calculating settings for the studied systems.

The cardio-ankle vascular index (CAVI) is an indicator of arterial stiffness from the heart to the ankles. The CAVI increases as arteriosclerosis progresses, but it can be decreased by appropriate treatment. There are several risk factors for coronary artery disease, however, the degree of stress caused by each separate risk factor to arteries cannot be assessed. CAVI increases with age and according to the severity of atherosclerosis. We found that CAVI also changes in response to the control of risk factors, which may be associated with the functional stiffness of arteries. CAVI can be a useful indicator of risk control for coronary artery disease. We followed a patient aged 71 years who had diabetes mellitus and obstructive sleep apnea (OSA) by measuring CAVI for 8 years from age 63. He underwent coronary artery bypass grafting due to angina pectoris when he was 63 years old. Before coronary artery bypass grafting, CAVI was 11.8 on the right and 11.5 on the left. Three years later he was found to have OSA and received treatment with continuous positive airway pressure. There was a marked improvement in CAVI after continuous positive airway pressure (age 68; right 10.4, left 10.2). However, following a gradual increase in body weight and worsening of diabetes mellitus, CAVI showed an increasing trend. CAVI decreased with biguanides treatment, but increased again with an increase in body weight. In conclusion, CAVI responded to the patient's conditions including obesity, diabetes mellitus, and OSA. CAVI is not only a marker of arterial stiffness, but can also be a useful indicator of physiological status; it may be effective in total risk control for coronary artery disease.

Kazuhiro Shimizu,1 Tomoyuki Yamamoto,2,3 Mao Takahashi,1 Shuji Sato,1 Hirofumi Noike,1 Kohji Shirai2 1Department of Internal Medicine, 2Department of Vascular Function, Toho University Sakura Medical Center, Chiba, 3Biological Information Analysis Section, Fukuda Denshi Co., Ltd, Tokyo, Japan Purpose: The purpose of this study was to clarify the difference between effects of nitroglycerin (NTG) on the functional stiffness in patients with and without coronary artery disease (CAD) using a newly developed stiffness index, cardio-ankle vascular index (CAVI).Subjects and methods: The two subject groups in this study were normal controls (n=31) and CAD patients (n=25). The normal controls had no medical history and were not on regular medications. On the other hand, the CAD patients had received various treatments like antihypertensive drugs, hypoglycemic agents, and statins. This study was conducted in CAD patients under medications. After a single sublingual administration of NTG 0.3 mg, CAVI, blood pressure (BP), and heart rate (HR) were measured every 5 minutes for 20 minutes. Comparisons of each parameter before and after taking NTG were evaluated for statistical significance using analysis of variance and post hoc tests. Tukey–Kramer test was used for post hoc comparisons.Results: In the normal controls, CAVI significantly decreased from baseline after 5, 10, and 15 minutes (from 6.5±0.9 to 5.2±0.9, 5.5±0.9, and 5.7±0.9, respectively). Systolic BP and HR were not significantly changed. Diastolic BP significantly decreased from baseline after 5 and 10 minutes (from 72±8 to 64±9 and 63±9 mmHg, respectively). On the other hand, CAVI, HR, and diastolic BP were not changed significantly in CAD patients. Systolic BP was significantly decreased from baseline after 5, 10, and 15 minutes (from 147±16 to 131±14, 129±12, and 129±13 mmHg, respectively). In the comparison of the two groups, ΔCAVI was not significantly different between the normal controls and CAD patients (–1.4±0.7 vs –1.4±0.9, –1.1±0.7 vs –1.4±1.0, –0.8±0.7 vs –1.2±1.0, and –0.5±0.7 vs –1.1±1.0 at 5, 10, 15, and 20 minutes, respectively). ΔHR was not significantly different between the two groups. ΔSystolic BP in the CAD patients was significantly higher than in the normal controls at 5, 10, 15, and 20 minutes (normal controls vs CAD; –3±7 vs –10±11, –3±5 vs –10±11, –3±6 vs –13±10, and –1±6 vs –11±10 mmHg, respectively). ΔDiastolic BP in the normal controls was significantly higher than in the CAD patients at 5 and 10 minutes (normal controls vs CAD; –8±6 vs –4±4 and –9±4 vs –6±5 mmHg, respectively). Conclusion: After NTG administration, the stiffness of the arteries from the origin of the aorta to the ankle as measured by CAVI decreased in both the normal controls and CAD patients, indicating that the response of arterial smooth muscle cells to nitric oxide is preserved even in CAD patients under medication. Keywords: arterial stiffness, cardio-ankle vascular index, nitroglycerin, nitric oxide, stiffness parameter

A rapid and sensitive flow method, based on the combination of on-line solvent extraction with reversed micellar mediated chemiluminescence (CL) detection using rhodamine B (RB), was developed for the determination of antimony(III) and antimony(V) in aqueous samples. The on-line extraction procedure involved ion-pair formation of the antimony(V) chloro-complex anion with the protonated RBH(+) ion and its extraction from an aqueous hydrochloric acid solution into toluene, followed by phase separation using a microporous membrane. When in a flow cell of a detector, the ion-pair in the extract driven was mixed with the reversed micellar solution of cetyltrimethylammonium chloride in 1-hexanol-cyclohexane/water (0.60 mol dm(-3) H2SO4) containing cerium(IV), its uptake by the reversed micelles and the subsequent CL oxidation of RB with Ce(IV) occurred easily, then the produced CL signal was measured. Using the proposed flow method under the optimized experimental conditions, a detection limit (DL) of 0.35 μmol dm(-3) and a linear calibration graph with a dynamic range from DL to 16 μmol dm(-3) were obtained for Sb(V) with a precision of 1.4% relative standard deviation (n = 5) at the Sb(V) concentration of 8.2 μmol dm(-3). The present method was successfully applied to the determination of Sb(V) in water samples and to the differential determination of Sb(III) and Sb(V) in copper electrolyte industrial samples, where total antimony Sb(III) + Sb(V) was determined after oxidation of Sb(III) to Sb(V) with Ce(IV) and Sb(III) was calculated by difference, for which the DL was almost the same as that for Sb(V).