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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.%.

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.

The rapidly rising demand for energy storage systems presents an imperative need to develop sodium-ion batteries with high energy density, high conductivity, and low barrier energy. In this work, we present a Density Functional study on the properties of two-dimensional NaxSiS as a promising anode material for rechargeable sodium-ion batteries. Energetically stable structures of Na-adsorbed silicene sulfide NaxSiS with various Na contents were explored. It is found that the adsorption energy of a Na atom is higher than -0.4 eV and it decreases with increasing Na content. The electronic structure of pristine silicene sulfide shows semiconductor behaviour with a bandgap of 0.99 eV, while the Na-adsorbed SiS exhibits metallic characteristics. The highest theoretical capacity of 187.2 mA h g-1, which is higher than that of well-known two dimensional materials, is found in the fully intercalated phase of SiS Na0.5SiS which corresponds to per side layer. Furthermore, Na ions can diffuse along two typical pathways on the surface of SiS with a small barrier of 183 meV which is much smaller than that of the two dimensional LixSiS, NaxTiS2, and NaxMoS2. All these characteristics suggest that silicene sulfide SiS can be expected to be a promising anode material for sodium ion batteries.

We calculate transverse spin susceptibility in the linear response method based on the ground states determined in the quasiparticle self-consistent $GW$ (QSGW) method. Then we extract spin-wave (SW) dispersions from the susceptibility. We treat bcc Fe, hcp Co, fcc Ni, and B2-type FeCo. Because of the better description of the independent-particle picture in QSGW, calculated spin stiffness constants for Fe, Co, and Ni give much better agreement with experiments in QSGW than those in the local density approximation (LDA); the stiffness for Ni in LDA is two times greater than in experiment. For Co, both acoustic and optical branches of SWs agree with experiment. As for FeCo, we have some discrepancy between the spin stiffness in QSGW and that in experiment. We may need further theoretical and experimental investigations on the discrepancy.

A specific pattern of morphological changes in the human brain is observed during the process of brain development and healthy aging. The age of subjects can be estimated from brain images by evaluating such patterns. This paper proposes an age estimation method using 3-Dimensional Convolutional Neural Network (3D-CNN) from brain T1-weighted images so as to fully utilize the potential of volume data. Through a set of experiments using over 1,000 T1-weighted images of healthy Japanese, we demonstrate that the proposed method exhibits better performance on age estimation than the conventional methods using handcrafted local features and 2D-CNN.

Many species live in spatially separated patches, and individuals can migrate between patches through paths. In real ecosystems, the capacities of patches are finite. If a patch is already occupied by the individuals of some species, then the migration into the patch is impossible. In the present paper, we deal with prey-predator system composed of two patches. Each patch contains a limited number of cells, where the cell is either empty or occupied by an individual of prey or predator. We introduce “swapping migration” defined by the exchange between occupied and empty cells. An individual can migrate, only when there are empty cells in the destination patch. Reaction-migration equations in prey-predator system are presented, where the migration term forms nonlinear function of densities. We numerically solve equilibrium densities, and find that the population dynamics are largely affected by nonlinear migration. Not only extinction points but also the responses to the environmental changes crucially depend on the patch capacities.

Background. Deep brain stimulation of the subthalamic nucleus (STN-DBS) is a surgical treatment to reduce the “off” state motor symptoms of Parkinson’s disease (PD). Postural instability is one of the major impairments, which induces disabilities of activities of daily living (ADLs). The effectiveness of STN-DBS for postural instability is unclear, and the effect of rehabilitation following STN-DBS has remained uncertain. Objective. The purpose of this study was to examine changes in balance ability, gait function, motor performance, and ADLs following 2 weeks of postoperative rehabilitation in PD patients treated with STN-DBS. Methods. Sixteen patients were reviewed retrospectively from February 2016 to March 2017. All patients were tested in their “on” medication state for balance and gait performance using the Mini-Balance Evaluation Systems Test (Mini-BESTest) and the Timed “Up and Go” (TUG) test before the operation, after the operation, and during the discharge period. The UPDRS motor score (UPDRS-III) and Barthel Index (BI) were assessed before the operation and during the discharge period. Rehabilitation focused on muscle strengthening with stretching and proactive balance training. Friedman’s test and the post hoc Wilcoxon’s signed-rank test were used to analyze the balance assessments, and ANOVA and the post hoc Tukey’s test were used to analyze gait performance. The significance level was p<0.05. Results. During the discharge period, the Mini-BESTest and TUG were significantly improved compared with the preoperative and postoperative periods (p<0.05). There were no differences between preoperative and postoperative periods in the Mini-BESTest (p=0.12) and TUG (p=0.91). The BI and motor sections of the UPDRS did not differ significantly between the preoperative and postoperative periods (p=0.45, p=0.22). Conclusion. The results of this study suggest that postoperative rehabilitation improves balance and gait ability in patients with PD treated with STN-DBS.

Recent discovery of the rotating magnetocaloric effect in rare-earth and transition metal compounds opens up a potential application for the next generation of the cooling device with fast operation time and compact size. However, there are few theoretical works on this phenomenon. We study the anisotropic magnetocaloric effect in MnP by combining first-principles calculations and Monte-Carlo simulations. The magnetocrystalline anisotropy energy is not negligible even above the Curie temperature due to the effect of the external magnetic field on the magnetization. The dependence of the isothermal magnetic entropy change on the direction of an applied magnetic field is quantitatively reproduced by using our model. The large rotating magnetic entropy changes in MnP are predicted theoretically.

We propose a new model and scheme to consider the effect of structural transformation on magnetocaloric properties of Mn1-xCuxCoGe. The magnetic exchange coupling constants are estimated from first-principles calculations based on density functional theory. The magnetic phase diagram is semi-quantitatively reproduced by using mean-field approximation. The giant isothermal magnetic entropy change with the magnetostructural coupling of Mn0.89Cu0.11CoGe alloy is well reproduced by using the modified Potts model. The enhancement of magnetostructural coupling on the isothermal magnetic entropy change strongly depends on the condition of the magnetic phase transition temperature of orthorhombic and hexagonal phases.

In this paper, the electronic structure and transport properties of a ductile thermoelectric material α-Ag2S are examined using first-principles calculations combined with the Boltzmann transport equation within a constant relaxation-time approximation. The use of the exchange–correlation functional SCAN + rVV10 successfully describes the geometric and electronic structure of α-Ag2S with a direct bandgap value of 0.99 eV, which is consistent with the previous experimental observations. Based on the calculations of the formation energy of typical intrinsic defects, it is found that intrinsic defect formation greatly affects the conductivity of the system where silver vacancy and interstitial silver act as p-type and n-type defects, respectively. Large Seebeck coefficients at room-temperature, of around −760 μV K−1 for n-type and 1400 μV K−1 for p-type, are realized. It is also suggested that the doping of fully filled d-block elements such as Cu and Au not only maintained the Seebeck coefficients at high values but also improved electrical conductivity by more than 1.4 times, leading to the improvement of the power factor by up to 40% compared to the non-doped sample at low carrier concentration.

Correction for ‘Intrinsic defect formation and the effect of transition metal doping on transport properties in a ductile thermoelectric material α-Ag2S: a first-principles study’ by Ho Ngoc Nam et al., Phys. Chem. Chem. Phys., 2021, DOI: 10.1039/d0cp06624a.

The construction and discontinuance processes of factories are complicated problems in sociology. We focus on the spatial and temporal changes of factories at Hamamatsu city in Japan. Real data indicate that the clumping degree of factories decreases as the density of factory increases. To represent the spatial and temporal changes of factories, we apply “contact process” which is one of cellular automata. This model roughly explains the dynamics of factory distribution. We also find “historical effect” in spatial distribution. Namely, the recent factories have been dispersed due to the past distribution during the period of economic bubble. This effect may be related to heavy shock in Japanese stock market.

A facile and surfactant-free peroxo-titanium sol-gel route has been developed to synthesize TiO2 composites with a two-phase mixture of anatase and rutile at 350 °C. Thermal analysis revealed that the anatase to rutile phase transformation occurs at ca. 325 °C. The absorption edge of the obtained two-phase TiO2 is red-shifted to ca. 420 nm, and its photocatalytic performance on CO2 reduction is on a par with TiO2 P25. To further enhance the photocatalytic activity, 0.1 mass% Pt was loaded by photoelectrodeposition, which led to a high CO2 photoreduction efficiency with selective formation of methane. The synthesis method is useful to fabricate composites containing anatase-rutile TiO2 and high-temperature sensitive substances such as carbon nanomaterials.

As an exotic material in spintronics, Gd-doped GaN is known as a room- temperature ferromagnetic material that possesses a large magnetic moment (4000 μBper Gd ion). This paper theoretically proposes that the large magnetic moment and room-temperature ferromagnetism observed in Gd-doped GaN is caused by N 2p holes based on the assumption that Ga-vacancies (VGa) result from the introduction of Gd ions via the volume compensation effect. This causes that the too large magnetic moment is estimated for Gd ions if only Gd ions contributed the magnetic moment.

In this study, we calculate the temperature-dependent electronic structures and transport properties of the Heusler alloy Co2MnSi on the basis of the Korringa–Kohn–Rostoker Green's function method combined with the coherent potential approximation (CPA). Temperature effects often have a significant influence on the spin-polarization properties of Heusler alloys. To incorporate the contributions of temperature effects, we first consider lattice vibrations and spin fluctuations. Using CPA, we can replace them with random displacements due to local phonons and local magnetic moment disorders, respectively. In the Co2MnSi Heusler alloy, we found that the band structures are smeared by the electron–phonon scattering process and the half-metallic property is eliminated by magnon excitations from the spin-up to spin-down states. Furthermore, we can estimate the electrical resistivity as a function of temperature in the scheme of linear response theory. Including the local phonon disorder, local moment disorder, and Mn–Co antisite disorder in CPA, we can reproduce the temperature-dependent resistivity observed by experiments.

We study a food-web model which is known to exhibit a parity law: the behavior of stationary state differs by whether the species number is odd or even. Here we deal with the same ecosystem in patc...

We calculated spin-wave dispersion of ferromagnetic Heusler alloys; Cu2MnAl, Ni2MnSn, and Pd2MnSn from the dynamical spin susceptibility based on the ground states determined by the quasi-particle ...

The relationship between the valence states of Eu ions in Eu-doped GaN and their magnetic properties is investigated by experiments and simulations. X-ray measurements have verified that the valence states of Eu ions can be controlled through growth temperature and codopants and that the highest concentration of divalent Eu ions is found in samples grown at 700 ° C by codoping with Si and O. According to our phenomenological analysis, magnetoresistance measurement implies the presence of Zener’s p–f exchange interaction. However, the magnetization dependence on an external magnetic field shows non-hysteretic sigmoidal curves in all the samples. Our simulations suggest that this is due to the formation of nanostructures of the magnetic impurities in the samples by spinodal decomposition.The relationship between the valence states of Eu ions in Eu-doped GaN and their magnetic properties is investigated by experiments and simulations. X-ray measurements have verified that the valence states of Eu ions can be controlled through growth temperature and codopants and that the highest concentration of divalent Eu ions is found in samples grown at 700 ° C by codoping with Si and O. According to our phenomenological analysis, magnetoresistance measurement implies the presence of Zener’s p–f exchange interaction. However, the magnetization dependence on an external magnetic field shows non-hysteretic sigmoidal curves in all the samples. Our simulations suggest that this is due to the formation of nanostructures of the magnetic impurities in the samples by spinodal decomposition.

This study computationally demonstrates that room-temperature ferromagnetism, which has been experimentally observed in Eu-doped GaN, is induced by holes in N 2p states (i.e., Zener’s double exchange interaction) that arise on the assumption that Ga vacancies appear as a result of the introduction of Eu ions (i.e., volume compensation). The calculated Curie temperature (TC) suddenly increases over a certain range of Ga-vacancy concentrations and gradually increases with an increasing concentration of Eu ions. High TC above room temperature is dominated by Zener’s double exchange mechanism in partially occupied N 2p hole-states, which itinerate throughout the whole crystals, and low TC is dominated by Zener’s p-f exchange mechanism in Eu 4f and N 2p hybridization. We can reasonably explain the surprising experimental data of 4000 μB per Gd atom in Gd-doped GaN reported by Dhar et al. [Phys. Rev. Lett. 94, 037205 (2005)].

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.

This study considers comprehension of manga as part of establishing an effective teaching method of reading comprehension for manga. Specifically, the learning program to foster media literacy through reading, interpretation, and appreciation of manga for fifth - grade students were organized and analyzed using the framework of the existing text comprehension model. According to the analyses, models such as this kind of sentence-level understanding may also be present in the reading of manga. In the reading of manga, multiple levels of comprehension may need to be taught, including surface-level, text-based, and situation models.

The age of a subject can be estimated from the brain MR image by evaluating morphological changes in healthy aging. We consider using two-types of local features to estimate the age from T1-weighted images: handcrafted and automatically extracted features in this paper. The handcrafted brain local features are defined by volumes of brain tissues parcellated into 90 or 1,024 local regions defined by the automated anatomical labeling atlas. The automatically extracted features are obtained by using the convolutional neural network (CNN). This paper explores the difference between the handcrafted features and the automatically extracted features. Through a set of experiments using 1,099 T1-weighted images from a Japanese MR image database, we demonstrate the effectiveness of the proposed methods, analyze the effectiveness of each local region for age estimation and discuss its medical implication.

Gd2O3-modified CeO2 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 Gd2O3-modified CeO2 is significantly higher than that of pure CeO2. A solid solution Gd0.1Ce0.9O1.95 phase coexisting with the CeO2 matrix phase shows a high ability of photoelectrodeposition for the Pb(II) ions removal, compared to the two-phases mixture of Gd2O3–CeO2. The high photocatalytic activity is also supported by a strong photoluminescence (PL) signal from the Gd0.1Ce0.9O1.95–CeO2. The high activity can be due to a formation of heterojunctions between p-type Gd0.1Ce0.9O1.95 and n-type CeO2, promoting transfer of photogenerated electron–hole pairs and efficiency restraining recombination of the charges.

Ab initio electronic structure calculation of a series of Co2FeAl1−xSix Heusler alloys has been performed, using the Korringa–Kohn–Rostoker-coherent potential approximation method to explain experimental 59Co NMR spectra. Two prominent features are explained semi-quantitatively—a global shift of the 59Co resonance line due to alloying with Al and Si atoms in Co2FeAl1−xSix, and the effect of local disorder in creating distinct satellite lines of 59Co NMR in Co2FeAl. The importance is stressed of the positive contribution to the 59Co hyperfine field from valence electron polarization, which emerges from the half-metallic band structure inherent in Co-based Heusler alloys.

The phosphidation of a ZnO/GaN solid solution photocatalyst enhanced significantly its activity for water splitting. The photocatalysts were heated with phosphorus in a vacuum-sealed quartz tube. Activation due to phosphidation was restricted within the narrow temperature range of 823–873 K, and varying amounts of P were added to the solid solution. In addition to X-ray diffraction peaks due to ZnO/GaN, active phosphide ZnO/GaN provided a single GaP peak with diffraction angles higher than normal GaP by 2θ = 0.20–0.44°, indicative of the formation of a GaP1−xNx alloy system. The diffraction peaks were simulated using first principles Ab inito calculations on molecular models of Ga32P32−yNy. The comparison with experimental shifts showed that the highest activity was induced in an x range of 0.034–0.074 of GaP1−xNx.

Many researchers have shown an interest in Ge-based dilute magnetic semiconductors (DMSs) due to potential advantages for semiconductor spintronics applications. There has been great discussion about mechanisms of experimentally observed ferromagnetism in (Ge,Fe) and (Ge,Mn). We investigate the electronic structures, structural stabilities, magnetic exchange coupling constants, and Curie temperature of Ge-based DMSs, and clarify origins of the ferromagnetism, on the basis of density functional theory calculations. In both the (Ge,Fe) and (Ge,Mn) cases, the inhomogeneous distribution of the magnetic impurities plays an important role to determine the magnetic states; however, physical mechanisms of the ferromagnetism in these two materials are completely different. By the spinodal nanodecomposition, the Fe impurities in Ge gather together with keeping the diamond structure, so that the number of the first-nearest-neighbor Fe pairs with strong ferromagnetic interaction increases. Therefore, the Curie temperature drastically increases with the progress of the annealing. Our cluster expansion method clearly reveals that the other ordered compounds with different crystal structures such as ${\mathrm{Ge}}_{3}{\mathrm{Mn}}_{5}$ and ${\mathrm{Ge}}_{8}{\mathrm{Mn}}_{11}$ are easily generated in the (Ge,Mn) system. The estimated Curie temperature of ${\mathrm{Ge}}_{3}{\mathrm{Mn}}_{5}$ is in agreement with the observed Curie temperature in experiments. It should be considered that the precipitation of the ferromagnetic ${\mathrm{Ge}}_{3}{\mathrm{Mn}}_{5}$ clusters is an origin of high Curie temperature in (Ge,Mn).

Statistical analysis using large-scale brain magnetic resonance (MR) image databases has examined that brain tissues have age-related morphological changes. The age of a subject can be estimated from the brain MR image by evaluating morphological changes with healthy aging. This paper proposes an age estimation method using local features of T1-weighted MR images. The brain local features are defined by volumes of brain tissues parcellated into 1,024 local regions defined by the automated anatomical labeling atlas. This paper also proposes the effective local feature selection method to improve the accuracy of age estimation. We evaluate the accuracy of the proposed method using 1,099 T1-weighted images from a Japanese MR image database. We also analyze effectiveness of each local region for age estimation and discuss its medical implication.

Carbon deposition on Ni-based anode is well-known as a major barrier for the practical use and commercialization of hydrocarbon-fuelled solid oxide fuel cells (SOFCs). In this work, Co alloying in Ni-YSZ was studied as an alternative anode material for using CH 4 as a fuel. The Ni-YSZ and Ni-Co alloyed-YSZ were prepared by the traditional impregnation method without further mixing processes. After sintering and reduction in H 2 atmosphere, the introduced Co can completely dissolved into the Ni lattice and changed the morphology with an increase in the Ni-YSZ grain size and showed a better uniform microstructure. The Co alloying also enhanced the electrochemical performance under CH 4 fuel by reducing the resistance and anodic overvoltage. Moreover, the Co addition enhanced the stability of the cell with CH 4 a constant load current of 80 mA for 60 h. This performance related to the carbon deposition on the anode surface. The Co alloying showed a high efficiency to suppress the carbon deposition and improved the electrochemical performance of an SOFC cell operating under CH 4 fuel.

This chapter presents examples of medical image understanding algorithms using computational anatomy models explained in Chap. 2. After the introductory in Sect. 3.1, Sect. 3.2 shows segmentation algorithms for vertebrae, ribs, and hip joints. Segmentation algorithms for skeletal muscle and detection algorithms for lymph nodes are explained in Sects. 3.3 and 3.4, respectively. Section 3.5 deals with algorithms for understanding organs/tissues in the head and neck regions and starts with computational neuroanatomy, followed by analysis and segmentation algorithms for white matter, brain CT, oral regions, fundus oculi, and retinal optical coherence tomography (OCT). Algorithms useful in the thorax, specifically for the lungs, tracheobronchial tree, vessels, and interlobar fissures from a thoracic CT volume, are presented in Sect. 3.6. Section 3.7 provides algorithms for breast ultrasound imaging, i.e., mammography and breast MRI. Cardiac imaging algorithms in an echocardiographic image sequence and MR images as well as coronary arteries in a CT volume are explained in Sect. 3.8. Section 3.9 deals with segmentation algorithms of abdominal organs, including the liver, pancreas, spleen, kidneys, gastrointestinal tract, and abdominal blood vessels, followed by anatomical labeling of segmented vessels.

Progressive multifocal leukoencephalopathy (PML) is a subacute demyelinating disease of the brain caused by the JC virus that occurs mainly in immunocompromised patients. The prognosis is very poor. As the lesion looks like non- specific leukoencephalopathy, making a diagnosis at the early stage is very difficult. We report three PML cases in which there was a mismatch between (11)C-methionine-positron emission tomography (MET-PET) uptake and (18)F-fluorodeoxyglucose-positron emission tomography (FDG-PET) uptake. All three cases demonstrated the hyper-uptake of MET around the white matter lesions and hypo-uptake of FDG inside the lesions. We speculate that the infection had ended inside the white matter lesions of these patients, while JC virus infection was ongoing around the lesions, resulting in the increase of methionine metabolism, and the glucose metabolism was reduced or intermediate because inflammatory cells infiltrate PML lesions rarely. Two patients who were diagnosed and treated with mefloquine while the JC virus was at a low level in the cerebrospinal fluid are still alive. We suggest the usefulness of MET-PET for the early diagnosis of PML and early treatment with mefloquine.

Ni/Gd-doped CeO2 (Ni-GDC) cermet is employed as a solid oxide fuel cell anode operating at 800°C. The single cells are a Ni-GDC/YSZ/LSM-YSZ structure. A novel plasticizer, 1,3-propanediol, is introduced into the fabrication process along with the use of the conventional organic binder PVB. Effects of anode compositions, 50% and 60% NiO, and additive types (PVB/PPD and PVB/PEG) on microstructure and electrical conductivity are compared. The results show that a more uniformity grain and pore distribution in the anode and a suitable additive enhances electrical conductivity. An improvement of cell performance with reduced total internal resistance is also observed.