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High Ohmic resistance of the solid electrolyte film is a critical issue of low-temperature solid oxide fuel cells (SOFCs) that needs to be addressed. In this study, tailored ceramic Gd-doped ceria (GDC) nanocubes with highly reactive {100} facets were densely integrated on a low-temperature-sinterable (La 0.6 Sr 0.4) 0.95 Co 0.2 Fe 0.8 O 3-δ (LSCF) cathode support by electrophoretic deposition (EPD). The densely packed GDC nanocube thin film was co-sintered with the cathode support at a significantly lower temperature of 1000 °C, which is 300 °C lower than that required for conventional GDC nanoparticles. The well-sintered dense GDC solid electrolyte thin film formed a 1 μm thick layer on the porous cathode support. The anomalous low-temperature sintering was achieved owing to the good sinterability of the GDC nanocubes, their high-density integration on the LSCF support by EPD, and a remarkable shrinkage of the LSCF support. The deposition of a porous cathode functional layer (CFL) with fine carbon nanoparticles as a pore-forming agent yielded a flat surface. The CFL enabled the integration of GDC nanocubes densely on the LSCF cathode support and remained as a preferable contact interlayer. The GDC nanocube-integrated LSCF cathode support fabricated in this work can be a suitable material for low-temperature solid oxide fuel cells. [Display omitted] • GDC nanocube film was densely integrated on a porous LSCF support by EPD. • Very fine LSCF nanoparticles were synthesized by a carbonate co-precipitation method. • A-site deficiencies in the LSCF support promoted its densification. • CuO sintering aid decreased the initial sintering temperature of LSCF to 800 °C. • A 1 μm thin GDC solid electrolyte film was fabricated by co-sintering at 1000 °C. [ABSTRACT FROM AUTHOR]

Stochastic cellular automata for rock-paper-scissors games are related to Lotka-Volterra model. Simulations are usually performed by two methods local and global interactions. It is well known that the population dynamics with local interaction is stable, where all species coexist. In contrast, global interaction leads to extinction. So far, theories such as mean-field theory and pair approximation have been presented, but they never explained the stable dynamics in local simulation. In the present article, we apply effective medium approximation (EMA) which has been developed in Physics. The effective medium is determined in a self-consistent way. The EMA theory well predicts the stability of population dynamics. Moreover, it fairly explains the aggregation of each species observed in the stationary state. [ABSTRACT FROM AUTHOR]

Abstract: Electrochemical performance of Ni1-xCox-GDC (Gd0.1Ce0.9O1.95) cermet was studied for the use as a novel anode for solid oxide fuel cells (SOFCs). Ni1-xCoxO (x=0.25, 0.5, 0.75) was prepared from NiO and Co3O4 compounds via a solid state calcination at 1000°C for 10h in air. A progressive increase in lattice parameters of the Ni1-xCoxO as x was increased suggested the extent of solid solution between NiO and Co3O4. The trace of free Co3O4 was found only in the Ni0.25Co0.75O calcined powder indicating incomplete dissolution between NiO and Co3O4 at this condition. After reduction at 800°C for 2h in H2, the interfacial polarization resistance and current-voltage (I-V) of the Ni1-xCox- GDC//YSZ//LSM-YSZ cells were measured at the temperatures between 650 and 800°C. Grain growth and coarsening of the Ni1-xCox-GDC cermet was generally observed when the amount of Co atomic fraction was increased especially at x = 0.75. The Ni0.75Co0.25-GDC anode exhibited the better uniform microstructure, as compared to other composite anodes, resulting in enhanced electrochemical performance of the cells. When the grain coarsening occurred, suppression of the overall electrochemical performance of the cells was obtained. [Copyright &y& Elsevier]

Abstract: Computational material design of a strategy for resource security of chalcopyrite-based photovoltaic solar cells (PVSC) is investigated. The electronic structure of CuIn (CIZTS) is calculated by using the self-interaction-corrected local density approximation (SIC-LDA) and the Korringa–Kohn–Rostoker coherent potential approximation (KKR-CPA). It is shown that for any degree of substitution for In, CIZTS has a direct band gap and no impurity state is induced in the band gap. We propose a possibility of substitutional co-doping of Zn and Sn for In in CuInSe2 photovoltaic material to reduce the cost of materials for PVSC production. [Copyright &y& Elsevier]

Much literature exists for rock-paper-scissors (RPS) game. It is well known in a single habitat that spatial models are more stable than well-mixed population. However, the mechanism of spatial stabilization has been unclear. In the present article, we study multilayer model of RPS game in a patchy environment; respective patches are set as lattices. The predation probability of one of three species is assumed to be reduced as a parameter. Simulations on two-layer system reveal the opposite result to those on a single-habitat system. Namely, the well-mixed population becomes stable. In contrast, extinction occurs by random migration in spatially-explicit model, when the reduced predation probability is below a certain critical value. The extinction in spatial model is found to be caused by the collapse of a kind of swarm intelligence (SI). In RPS system, large swarms of each species are automatically protected from its predator. Such a self-organized protection is one of the simplest examples of SI. We also discuss some serious problems for random migration. • Spatial pattern of rock, paper and scissors are studied in patchy environment. • A distinct point of the present paper is to set lattices as respective patches. • We illustrate that biodiversity is sustained by a kind of "swarm intelligence". • Large swarms of each species are automatically protected from its predator. [ABSTRACT FROM AUTHOR]

Abstract: Material designs based on the first principle calculations of electronic structures are proposed for α-quartz SiO2-based dilute magnetic semiconductors. The incorporation of transition metals (TMs) into Si sites and of the non-TM atoms into O sites are treated for various concentrations. At temperatures higher than room temperature, most of the TM-doped SiO2 have no magnetism, yet Si1−x Mn x O2 might achieve the ferromagnetism. The substitution of O by non-TM atoms as C or N also induces the magnetism in the host. However, while the N''s substitution induces the ferromagnetism, C''s substitution causes an anti-ferromagnetic behavior in the host material SiO2. [Copyright &y& Elsevier]

To develop a high-resolution in vivo human neuroanatomy database for Japanese brains, a data set on 1547 normal subjects between the ages of 16 and 79 years has been collected. First, we determined individual reference brains of normal Japanese for each age and gender group. We found there exists cross-generational changes in brain shape, that is, the young generation has a shorter and wider brain than the older generation. Second, we determined the effect of aging on the volume of gray matter and white matter by voxel based morphometry. A significant negative correlation between the gray matter volume and age was observed. We assume that this kind of database is quite useful to investigators who are engaged in basic neuroscience, clinical diagnostics and evaluation of neuropsychiatric disorders in patients. [Copyright &y& Elsevier]

We study population dynamics on lattice space with N species (N=3, 4, 5, and 6) with cyclic competitive advantage, having both a weaker species and a stronger one. The steady state with equal population densities is the globally stable fixed point. For the biased-rate cyclic advantage population, we can observe the different features of the steady states and their stabilities for even N and for odd N, and we call it as “parity law”. We obtain the following results on the parity law: (i) for odd number N all the species can coexist following the biased rate and we have the counterintuition for the change of equilibrium densities; (ii) for even N all the species cannot always coexist and it coincides with our intuition. We also analyzed mean-field approximation. It is revealed that most of the results of Monte Carlo simulation can be understood by mean-field approximation dynamics. However, equilibrium densities cannot be always predicted by mean-field approximation because of the spatial fixation. [Copyright &y& Elsevier]

Abstract: Based on ab initio electronic structure calculations by self-interaction-corrected local-density-approximation (SIC-LDA) with the Korringa–Kohn–Rostoker coherent potential approximation (KKR-CPA), we propose a materials design for high efficiency photovoltaic solar cells (PVSCs). It is shown that (i) the concentration dependence of the mixing energy of CuIn1−xGaxSe2 shows upward convexity, thus this system favors phase separation. Due to the type II band alignment between CuInSe2 and CuGaSe2, efficient electron–hole separation is realized in decomposed phase of this system. (ii) CuIn1−xZn0.5xSn0.5xSe2 has a direct band gap and no impurity state appears in the gap. Therefore, cost reduction is possible by using Zn and Sn instead of In. (iii) n-type CuAl1−xSnxS2 and p-type Cu1−xVCuxAlS2 have negative activation energy for doped impurities and are expected to be low-resistive transparent conducting sulfides, which should be useful for CuInSe2-based PVSCs. [Copyright &y& Elsevier]

Many species live in spatially separated patches. In real ecosystems, the capacity of patch is finite. If a patch is already occupied by the individuals of some species, then the migration into the patch is impossible. For the migration, empty cells are necessary in the destination patch ("nonlinear migration"). In the present article, we deal with two-patch system composed of prey and ambush predator. Preys can migrate between both patches, but predators stay in a single patch. Agent-based model (ABM) is applied in respective patches. Each patch contains a finite number of cells; "capacity" of a patch is defined by the total cell number in the patch. Each cell is either empty or occupied with prey or predator. Reaction-migration equations are presented for non-spatial system of ABM. Both non-spatial and spatial models indicate that the population dynamics are largely affected by the finiteness of respective patches. In particular, we find a self-organized habitat segregation, depending on parameter values. The prey density becomes nearly zero in the predator patch, although many preys live in non-predator patch. Although the migration occurs between both patches, the prey almost disappears in one patch. Such a segregation may be caused by the finite capacity of patches. • We deal with two-patch system composed of prey and ambush predator. • Nonlinear migration is applied. • The population dynamics are largely affected by patch capacities. • The self-organized habitat segregation is clearly observed by spatial simulations. [ABSTRACT FROM AUTHOR]

The conventional solid oxide fuel cell (SOFC) anode, which consists of metallic Ni and yttria-stabilized zirconia (YSZ), is liable to deactivation when a carbon-containing gaseous fuel is directly supplied. To retard the degradation due to a direct supply of CH 4 , the Ni/YSZ has been modified with the incorporation of Co into the Ni matrix, forming a substitutional solid-solution alloy. As a result, the porous anode exhibits well-connected compositional grains owing to the Co 3 O 4 precursor as a sintering aid. The 25 mol% Co incorporation producing the Ni 0.75 Co 0.25 /YSZ anode significantly improves the cell performance and prolonged stability. In addition, the Ni 0.75 Co 0.25 /YSZ anode provides the apparent activation energy of the charge transfer reaction to a lower value in the electrochemical oxidation of CH 4 at the triple-phase boundary. However, the apparent activation energy decrease is not identified for H 2. The Co alloying effect on catalyzing the electrochemical oxidation of CH 4 is caused by suppressing the carbon deposition originating from the thermal dissociation of adsorbed CH 4 on the Ni 1- x Co x alloy surface. [Display omitted] [ABSTRACT FROM AUTHOR]

We present a new oral intake route in a hypopharyngeal cancer patient with severe complications. A 64-year-old man was diagnosed as having T2N0M0 squamous cell carcinoma of the posterior wall of the hypopharynx. He had previously undergone radiotherapy for laryngeal cancer and tricuspid valve replacement surgery, and also had atrial flutter and renal dysfunction. We performed surgery with curative intent. The hypopharynx was primarily closed after tumor resection. Laryngotracheal separation and tracheoesophageal diversion with end-to-end anastomosis of the trachea to the esophagus was performed. After surgery, complete oral feeding was achieved using the new pathway created. The larynx, contradictory to its typical role, can be used as a pathway to the esophagus using our revolutionary technique. [ABSTRACT FROM AUTHOR]

Highlights: [•] SIRT1 induction by glucose deprivation plays an important role for protecting PC12 cells. [•] Reduced environmental glucose levels affect SIRT1 expression/localization. [•] The environmental glucose and NGF differentially controlled SIRT1 and FoxO3a. [ABSTRACT FROM AUTHOR]

Abstract: The focus of this study is to examine the distribution of defects and defect-induced properties in MgO-based magnetic tunnel junctions (MTJs). To this end, first-principles calculations were performed to estimate the electronic structures and total energies of MgO with various defects by using the Heyd–Scuseria–Ernzerhof (HSE06) hybrid functional. From connections drawn between the calculated results and previously reported experimental data, we propose that self-organized ferromagnetic nanowires of magnesium vacancies can be formed in MgO-based MTJs. This self-organization may provide the foundation for a comprehensive understanding of the conductivity, tunnel barriers and quantum oscillations of MgO-based MTJs. Further experimental verification is needed before firm conclusions can be drawn. [Copyright &y& Elsevier]

Abstract: We present a first-principles study of the magnetic properties of N-doped MgO, CaO and SrO, which have been proposed to constitute a new class of dilute magnetic semiconductors (DMSs) with no magnetic elements. In this study, it was found that under a homogeneously distributed condition, Curie temperatures could reach room temperature at sufficient N concentrations in the range of 20–30at.%; however, an inhomogeneous N distribution in these DMSs is the favored configuration, which indicates that spinodal decomposition leads to a room-temperature blocking temperature at smaller N concentrations than those estimated for room-temperature ferromagnetism in the homogeneous distribution condition. [Copyright &y& Elsevier]

Abstract: The rate at which the volume of gray matter declines with normal aging, and whether gender or generational differences affect this rate, remain unclear. Using a longitudinal design over 6 years in 381 healthy community-dwelling individuals, we examined the rate of age-related loss in global gray matter volume, and how gender, generational and cerebrovascular risk factors affected this rate. We collected brain magnetic resonance images of the subjects, and calculated gray matter and intracranial volumes at baseline and follow-up using a fully automated technique. Using these volumes we then calculated the gray matter ratio (GMR), which measures gray matter volume as a percentage of the total intracranial volume. There were significant main effects of age, gender, and body mass index, and an age×gender interaction in the annual percentage change in the GMR (APCGMR). The APCGMR of younger women was lower than that in older women and men. Our results may help in understanding the mechanism(s) of normal brain aging, and in distinguishing neurodegenerative diseases from normal aging. [Copyright &y& Elsevier]

Abstract: Several reports have presented patients with subacute cerebellar ataxia (CA) and Lambert-Eaton myasthenic syndrome (LEMS). Some clinical features of those patients have been described in the previous reports, manifestation of subacute CA prior to LEMS or a co-existence of both diseases, a high incidence of malignancy, and less efficacy of the treatment for subacute CA compared with that for LEMS. Cerebellar ataxia in some patients with LEMS has been suggested to be caused by antibodies to P/Q-type voltage-gated calcium channels (VGCCs). We report herein a patient with subacute CA and LEMS. Cerebellar ataxia appeared 15 months after the occurrence of LEMS, and the onset of CA was thought to be due to serum anti-P/Q-type VGCC antibodies. The clinical course of this patient was atypical, as follows: (1) LEMS preceded subacute CA, which developed after intracranial aneurysm surgery, (2) no malignancy was detected when both diseases co-existed, (3) symptoms of LEMS did not progress with the onset of CA, and (4) there was a definite improvement in symptoms of CA and 123I-IMP SPECT imaging findings after steroid administration. In addition, it is remarkable that LEMS became aggravated in electrophysiologic examinations, in contrast to subacute CA. We suggest that these atypical features of subacute CA and the changes in LEMS may be associated with a balance between the amount of serum anti-P/Q-type VGCC antibodies and the susceptibility of the cerebellum and presynaptic nerve terminals to the antibodies. More cases are needed to investigate the mechanisms involved. The subacute CA and LEMS in this patient have remained comparatively silent after the withdrawal of steroids, and we are continuing to observe her condition. [Copyright &y& Elsevier]

Introduction: Perry disease (Perry syndrome), a hereditary TAR DNA-binding protein 43 (TDP-43) proteinopathy, is caused by dynactin subunit 1 (DCNT1) mutations and is characterized by rapidly progressive parkinsonism accompanied by depression, apathy, unexpected weight loss, and respiratory symptoms including central hypoventilation and central sleep apnea. Meta-iodobenzylguanidine (MIBG) myocardial scintigraphy is considered a diagnostic biomarker for Lewy body disease (LBD), as denervation of cardiac sympathetic nerves is a pathological feature in LBD. However, our previous studies have reported a decreased cardiac uptake of MIBG in patients with Perry disease. In this study, we aimed to correlate the MIBG myocardial scintigraphy findings with clinical features in Perry disease.Methods: We evaluated data obtained from a multicenter survey of patients of Japanese origin with suspected Perry disease, who visited neurology departments in Japan from January 2010 to December 2018. We screened each patient's DNA for the DCTN1 mutation using Sanger sequencing and obtained the clinical details of all patients including findings from their MIBG myocardial scintigraphy.Results: We identified two novel mutations, p.G71V and p.K68E, in DCTN1 in patients from two different families. The majority of patients (7/8, 87.5%) showed a decrease in cardiac uptake (heart to mediastinum ratio) in MIBG myocardial scintigraphy. These patients commonly presented with symptoms related to autonomic dysfunction: constipation, fecal incontinence, urinary disturbance, and orthostatic hypotension.Conclusions: MIBG myocardial scintigraphy may be a useful biomarker of autonomic dysfunction in Perry disease. [ABSTRACT FROM AUTHOR]

We have fabricated a pseudo single crystal of cementite under a rotating magnetic field and investigated its easy and hard axes of magnetization, and determined its magnetocrystalline anisotropy energy. The obtained results are as follows: the hard and easy axes of cementite are the a- and c -axes of the orthorhombic structure with the space group Pnma , respectively. The hard axis observed experimentally was in good agreement with that obtained by an ab initio calculation; however, such consistency was not observed for the easy axis. The magnetocrystalline anisotropy energy was determined as 334 ± 20 kJ/m 3 at 5 K. [ABSTRACT FROM AUTHOR]

Depending on Pd content, disordered Fe-Pd alloys take various crystal structures: body-centered cubic (BCC), body-centered tetragonal (BCT), face-centered tetragonal (FCT) and face-centered cubic (FCC) structures. We have measured specific heat of Fe-Pd alloys to understand the lattice stability and electronic state of the alloys. At the phase boundary between FCT and FCC phases, electronic specific heat coefficient shows a local maximum and the Debye temperature shows a local minimum. A local maximum of electronic specific heat coefficient also appears in the BCC region with Pd content of near 10 at.%. [ABSTRACT FROM AUTHOR]

Gd 2 O 3 -modified CeO 2 particles are prepared by a solid-state reaction method, and are used to remove Pb(II) ions from aqueous solutions by a photoelectrodeposition. The UV–photocatalytic activity for Pb(II) ion removal of the Gd 2 O 3 -modified CeO 2 is significantly higher than that of pure CeO 2 . A solid solution Gd 0.1 Ce 0.9 O 1.95 phase coexisting with the CeO 2 matrix phase shows a high ability of photoelectrodeposition for the Pb(II) ions removal, compared to the two-phases mixture of Gd 2 O 3 –CeO 2 . The high photocatalytic activity is also supported by a strong photoluminescence (PL) signal from the Gd 0.1 Ce 0.9 O 1.95 –CeO 2 . The high activity can be due to a formation of heterojunctions between p-type Gd 0.1 Ce 0.9 O 1.95 and n-type CeO 2 , promoting transfer of photogenerated electron–hole pairs and efficiency restraining recombination of the charges. [ABSTRACT FROM AUTHOR]

Abstract: The effects of divalent metal ion doping on the photocatalytic activity of GaN powder for overall water splitting were studied. The doping of Zn2+, Mg2+ and Be2+ to GaN converted it to be a remarkably active and stable photocatalyst in the presence of RuO2 as a co-catalyst. Both H2 and O2 were produced from the initial stage of UV light illumination, and the ratio of H2 to O2 attained at the stoichiometric ratio of 2.0 at stationary conditions. Main absorption of undoped GaN was at around 390nm, and a slight shift to longer wavelength occurred with the divalent metal ion-doped GaN. Undoped GaN showed photoluminescence peak due to band gap transition, whereas Zn2+ and Mg2+-doped GaN generated a broad photoluminescence peak having a center at around 450nm and a tail extending to 600nm. In RuO2-dispersed Mg2+-doped GaN, with increasing content of Mg in starting materials used for preparation, the activity increased, whereas photoluminescence intensity decreased. The role of divalent metal ion dopants is concluded to produce p-type GaN, which is able to increase the concentration and mobility of holes. [Copyright &y& Elsevier]

Abstract: Background: The brain morphological changes in subthreshold depression (sD) have not been clarified. We examined the structural difference in regional gray matter volume between community-dwelling elderly subjects with sD and age-matched nondepressed normal subjects by voxel-based morphometry (VBM) based on magnetic resonance imaging (MRI). Methods: Thirty-four community-dwelling elderly subjects with sD and 109 age-matched nondepressed normal subjects were studied by MRI. We defined subjects with sD as those who showed a Geriatric Depression Scale score of 15 or higher and a Mini Mental State Examination score of 22 or higher, and do not fulfill the criteria of major depressive disorder (MDD) in the Diagnostic and Statistical Manual for Mental Disorders IV. We collected brain magnetic resonance images of 34 subjects with sD and 109 age-matched normal subjects, and analyzed the difference in regional gray matter volume between these two groups by VBM. Results: Male subjects with sD had significantly smaller volumes of the medial part of the bilateral frontal lobes and the right precentral gyrus than normal male subjects. Limitations: We have not clarified the discrepancy in the results of gender difference. Conclusions: Our study revealed that even community-dwelling elderly male subjects with sD show bilateral prefrontal gray matter volume reduction, which was reported to be observed in elderly patients with MDD, although there is no significant volume reduction in the hippocampus, which was also reported to be observed in MDD. Our study may contribute to clarifying the mechanism underlying brain pathological changes in sD. [Copyright &y& Elsevier]

The objectives of this study were to evaluate the correlations of the volumes of the gray matter and white matter with age, and the correlations of the tissue probabilities of the gray matter and white matter with age and several cerebrovascular risk factors. We obtained magnetic resonance (MR) images of the brain and clinical information from 769 normal Japanese subjects. We processed the MR images automatically by correcting for inter-individual differences in brain size and shape, and by segmenting the MR images into the gray matter and white matter. Volumetry of the brain revealed a significant negative correlation between the gray matter volume and age, which was not observed between white matter volume and age. Voxel-based morphometry showed that age, systolic blood pressure, and alcohol drinking correlated with the regional tissue probabilities of the gray matter and white matter. [Copyright &y& Elsevier]

High Z T value and large Seebeck coefficient have been reported in the nanostructured Fe-doped Si–Ge alloys. In this work, the large Seebeck coefficient in Fe-doped Si–Ge systems was qualitatively reproduced from the computed electronic density of states, where a hybrid functional, HSE06, was used for an exchange-correlation functional, as well as a special quasi-random structure (SQS) for a disordered atomic configuration. Furthermore, by replacing Fe with other transition metals, such as Mn, Co, Ni, Cu, Zn, and Au, a dopant that produces a large Seebeck coefficient in Si–Ge alloy systems was explored. It was found that the Mn-doped system produces a large Seebeck coefficient comparable with the Fe-doped system. • Hybrid functional DFT is used to calculate Seebeck coefficient of SiGe alloys. • The investigation is applied to transition metal (Mn, Co, Fe, Ni, Cu, Zn, Au) doping. • Large Seebeck coefficient in Fe-doped SiGe systems was qualitatively reproduced. • Impurity states at band-edges of Fe-doped SiGe boost the Seebeck coefficient. • Large Seebeck coefficient is also found in Mn-doped SiGe due to these impurity states. [ABSTRACT FROM AUTHOR]