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IntroductionA knee-ankle-foot orthosis (KAFO) prevents knee buckling during walking and enables gait training for acute hemiplegic stroke patients with severe gait disturbances. Although the goal of gait training with a KAFO is to improve gait ability, that is, to acquire walking with an ankle-foot orthosis (AFO), it is not clear how gait training with a KAFO contributes to improving gait ability. Therefore, this study aimed to investigate the relationship between muscle activities during walking with a KAFO and the improvement of gait ability in hemiplegic stroke patients with severe gait disturbance.MethodsA prospective cohort study was conducted. Fifty acute hemiplegic stroke patients who could not walk with an AFO participated. Muscle activities of the paretic rectus femoris, biceps femoris, tibialis anterior, and soleus were assessed with surface electromyogram during walking with a KAFO. Electromyograms were assessed at the beginning of gait training and at the time the Ambulation Independence Measure score improved by 3 or higher, or discharge.ResultsEven in patients with complete hemiplegia, paretic rectus femoris, biceps femoris, and soleus showed periodic muscle activity during walking with a KAFO. Twenty-three patients improved to an Ambulation Independence Measure score of 3 or higher and were able to walk with an AFO (good recovery group). At the beginning of gait training, paretic rectus femoris muscle activity during the first double-limb support phase was significantly higher in the good recovery group than in the poor recovery group. The rectus femoris muscle activity significantly increased from before to after acute rehabilitation, which consisted mainly of gait training with a KAFO.DiscussionFor acute hemiplegic stroke patients with severe disturbance, the induction and enhancement of paretic quadriceps muscle activity during walking with a KAFO play an important role in acquiring walking with an AFO.

ObjectivesTo investigate the construct validity of the Trunk Impairment Scale (TIS), which was developed to assess trunk impairment in patients with stroke, in patients with Parkinson’s disease (PD).DesignThis retrospective, cross-sectional study enrolled consecutive PD inpatients. Correlation analysis was performed to clarify whether the TIS assessment was related to other balance functions, lower extremity muscle strength, or walking ability. Factor analysis was performed to see how the background factors of TIS differ from balance function, lower limb muscle strength, and walking ability.ResultsExamining the data of 471 patients with PD, there were relationships between TIS and the Mini-Balance Evaluation Systems Test (r = 0.67), Barthel Index (r = 0.57), general lower limb extension torque (r = 0.51), two-minute walk test (r = 0.54), Hoehn and Yahr stage (r = −0.61), and Movement Disorder Society Unified Parkinson’s Disease Rating Scale part III total points (r = −0.59). Factor analysis showed that TIS items were divided into three factors (an abdominal muscles and righting reflex component; a perception and verticality component; and a rotational component), differing from other scales that included clinical assessment items.ConclusionThe TIS can be useful for assessing the underlying trunk impairment as a basis for activities of daily living, gait function, and balance ability in patients with PD.

Employing Korringa–Kohn–Rostoker Green’s function methodology, our investigation elucidates the previously obscure origins of the anomalous temperature-dependent electrical resistivity behavior of (Ga,Mn)As ferromagnetic semiconductors. Phonon and magnon excitations induced by temperature effects are addressed via the coherent potential approximation, while the Kubo–Greenwood formula is employed to compute transport properties. Consequently, the anomalous temperature-dependent electrical resistivity arising from the ferromagnetic–paramagnetic transition is successfully replicated. Our examination of electronic structures and magnetic interactions reveals pivotal roles played by antisite defects and interstitial Mn atoms in governing this behavior. As this approach enables both the estimation of temperature-dependent transport properties and the assessment of underlying mechanisms from a microscopic standpoint, it holds significant potential as a versatile tool across diverse fields.

Abstract The infectious disease (COVID-19) causes serious damages and outbreaks. A large number of infected people have been reported in the world. However, such a number only represents those who have been tested; e.g. PCR test. We focus on the infected individuals who are not checked by inspections. The susceptible-infected-recovered (SIR) model is modified: infected people are divided into quarantined (Q) and non-quarantined (N) agents. Since N-agents behave like uninfected people, they can move around in a stochastic simulation. Both theory of well-mixed population and simulation of random-walk reveal that the total population size of Q-agents decrease in spite of increasing the number of tests. Such a paradox appears, when the ratio of Q exceeds a critical value. Random-walk simulations indicate that the infection hardly spreads, if the movement of all people is prohibited ("lockdown"). In this case the infected people are clustered and locally distributed within narrow spots. The similar result can be obtained, even when only non-infected people move around. However, when both N-agents and uninfected people move around, the infection spreads everywhere. Hence, it may be important to promote the inspections even for asymptomatic people, because most of N-agents are mild or asymptomatic.

Abstract In 2016, a countermeasure was announced against the Nankai Trough long‐period and long‐duration ground motions (LPGMs) in Japan. However, the response spectrum method (RSM), indicated by the Ministry of Construction notification Vol. 2009 (MCN), was out of the countermeasure. An RSM considering characteristic changes due to repeated deformations has also been proposed. However, since the damping correction formula of MCN was used, its applicability to LPMGs has not been sufficiently investigated. In this paper, a method is proposed to evaluate the influence of characteristic changes due to repeated deformations using RSM for LPGMs and seismically isolated buildings using the lead plug‐inserted laminated rubber (LRB).

To avoid the proneness to degradation due to coking in the operation of solid oxide fuel cells (SOFCs) directly running on methane (CH4) fuels, a modified porous anode of the Ni1−XCoX/YSZ (yttria-stabilized zirconia) cermet prepared by an impregnation method is presented. The influence of the Co alloying content on the cermet microstructure, SOFC characteristics, and prolonged cell performance stability has been studied. Co was incorporated into Ni and formed a solid solution of Ni1−XCoX alloy connected with the YSZ as the cermet anode. The porous microstructure of the Ni1−XCoX/YSZ cermet anode formed by sintering exhibited a grain growth with an increase in the Co alloying content. The electrochemical performance of the cells consisting of the Ni1−XCoX/YSZ cermet anode, the YSZ electrolyte, and the LSM (La0.8Sr0.2MnO3) cathode showed an enhancement by the Ni1−XCoX impregnation treatment for the respective supply of H2 and CH4 to the anode. The cell using the Ni0.75Co0.25/YSZ cermet anode (the Ni0.75Co0.25 cell) showed the highest cell performance among the cells tested. In particular, the performance enhancement of this cell was found to be more significant for CH4 than that for H2; a 45% increase in the maximum power density for CH4 and a 17% increase for H2 at 750 °C compared with the performance of the cell using the Ni/YSZ cermet anode. Furthermore, the prolonged cell performance stability with a continuous CH4 supply was found for the Ni0.85Co0.15 and Ni0.75Co0.25 cells at least for 60 h at 750 °C. These enhancement effects were caused by the optimum porous microstructure of the cermet anode with the low anodic polarization resistance.

Barreto et al. (2017) showed that the genotypic cyclic competition model with three phenotypes appearing as three morphs of male lizards' throats had the same equilibrium but a wider stability region as the corresponding phenotypic model. In this paper we re-examine stability conditions under the symmetric choice of parameters for the phenotypic model so we can set the same internal equilibrium densities for all three phenotypes. In this setting we compare the stability regions of cyclic allele dominance rule. Next we consider the dynamics on a two-dimensional square lattice space and then show the effect of this spatial structure on the stability of phenotypic model. We obtain the following results: (ⅰ) Cyclic allele dominance rule in a genotypic model gives a wider stable region of internal equilibrium than the allele dominance rule observed in lizards; and (ⅱ) spatial structure drastically changes dynamical behavior, especially when all three phenotypes coexist in almost all the parameter spaces when both competition and dispersal occur locally.

Background. The effects of subthalamic nuclear deep brain stimulation therapy (STN-DBS) and combined postoperative rehabilitation for patients with Parkinson’s disease with postural instability have yet to be well reported. This study investigated the effects of short-term postoperative rehabilitation with STN-DBS on physical function in patients with Parkinson’s disease. Methods. Patients diagnosed with Parkinson’s disease who were admitted to our hospital for STN-DBS surgery were included in this study. Data were prospectively collected and retrospectively analyzed. Postoperative rehabilitation consisted of muscle-strengthening exercises, stretching, and balance exercises for 40–60 minutes per day for approximately 14 days. The Mini-Balance Evaluation Systems Test (Mini-BESTest), Timed Up and Go test (TUG) seconds and steps, Trunk Impairment Scale (TIS), seconds for 10 times toe-tapping, lower limb extension torque using StrengthErgo240, and center of pressure sway in the quiet standing posture were evaluated preoperatively, postoperatively, and at discharge. Mini-BESTest changes were also evaluated in the two groups classified by the presence or absence of postural instability. One-way and two-way repeated measures analyses of variance were performed for each of the three periods of change, and paired t-tests with the Bonferroni method were performed as multiple comparison tests. A stepwise multiple regression model was used to identify factors associated with balance improvement. Results. A total of 60 patients with Parkinson’s disease were included, and there were significant increases in Mini-BESTest, TIS, StrengthErgo240, and postural sway during closed-eye standing compared to pre- and postoperative conditions at discharge (p

We present a method to determine the model Hamiltonians to treat rare-earth multiplets in solids from the results of the quasiparticle self-consistent GW (QSGW) method. We apply the method to trivalent Eu compounds EuCl_{3}, EuN, and Eu-doped GaN after examining free rare-earth ions. We solve the model Hamiltonian by the exact diagonalization. Our results justify applying the Dieke diagram to ions in solid, while its limitation is clarified. In particular, we show that the crystal fields cause sizable breaking of the Russell-Saunders coupling.

Liquid fuel-only injection into combustion air is widely used in gas turbine combustors for power generation, particularly in large capacity type. This combustion air goes by the name of ‘crossflow’. For the liquid fuel-only injection, breakup process, trajectory of liquid jet and droplet sizes have been extensively investigated. However, there remain much space to be devised for improvement in atomization. In the present study, twin-fluid injection is introduced instead of liquid-only injection into a gas turbine combustor, where atomization air is supplied through the side port and mixed with liquid in the mixing port at right angle, and two phases mixture is injected into the crossflow. A simple-structured twin-fluid atomizer is designed. An experimental study was conducted to compare the behaviours between liquid-only and twin-fluid injected transversely into a crossflow. High-speed photography technique is used to clarify the atomization characteristics of jet/spray. One feature of twin-fluid injection is that annular liquid film appears at the exit of the mixing port, and the film easily disintegrates by aerodynamical force of the crossflow. The jet/spray of the twin-fluid injection is not blown away easily by crossflow, and flow across the crossflow. Furthermore, the jet/spray of the twin-fluid spread and droplets disperse more widely in the crossflow. In addition, the twin-fluid injection produces numerous fine droplets and few coarse droplets.

In this paper we give a basic reproduction number $\mathscr{R}_0$ of an SEIRS model on regular lattice using next-generation matrix approach. Our result is straightforward but differs from the basic reproduction numbers for various fundamental epidemic models on the regular lattice which have been shown so far. Sometimes it is caused by the difference of derivation methods for $\mathscr{R}_0$ although their threshold of infectious rates for epidemic outbreak remain the same. Then we compare our $\mathscr{R}_0$ to the ones by these previous studies from several epidemic points of view.

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)].

Removal of lead ions from water was conducted by a coupling approach of adsorption and photoelectrodeposition over a macroporous CeO2 photocatalyst loaded with ZnO. The photocatalyst was prepared by the hard template method and the impregnation method. The various size of silica spheres (0.05-0.4 µm) were used as a template for the photocatalyst, and the highest BET surface area (73.8 m2/g) was given in the sample prepared with the smallest silica sphere (0.05 µm). In the removal of lead ions, the porous sample showed a large amount of removal of lead ions. In addition, the ZnO loaded catalysts showed a larger amount of removal for lead ions than an unloaded catalyst under the UV light irradiation. In the reaction, since zinc ions were simultaneously dissolved to the solution, it was suggested that this reaction was the ion-exchange reaction between lead ions and zinc ions and was promoted by the UV light irradiation.

There has been a great demand for flame stability particularly in low-grade residual oil-fired burners. In order to improve the performance of the residual oil burner, it is required to obtain the stable ignition by the swirler devices which create recirculating combustion gas and rotating fuel spray flows. In the present study, a numerical simulation was made on the flow behaviors of air circulation and droplet streamlines for two types of swirlers with different angles of guide vane. A stereo PIV measurement was also made on the velocity distribution of spray droplets. One type of the swirlers is a former type called “Bent plate swirler” with a constant bending angle of the guide vanes. The air after the guide vane expands to the outer circumferencial direction by centrifugal force and the swirling state abruptly declines. Another is a newly developed type “Wing-curved swirler” in which the bending angle of the guide vane becomes deeper from the center to the outer direction. The air flow maintains the swirling force and the recirculation flow is wider than the former “Bent plate swirler”. The Wing-curved swirler with a high swirl force, a swirl number of 2 or more, not only increases the swirl of the sprayed droplet but also lengthens its trajectories. The flame stability was improved by the burner equipped with the developed Wing-curved swirler. The decrease in dust concentration was demonstrated through the residual oil combustion test of the 10 MW actual burner.

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

Recent studies have demonstrated developmental changes of functional brain networks derived from functional connectivity using graph theoretical analysis, which has been rapidly translated to studies of brain network organization. However, little is known about sex- and IQ-related differences in the topological organization of functional brain networks during development. In this study, resting-state fMRI (rs-fMRI) was used to map the functional brain networks in 51 healthy children. We then investigated the effects of age, sex, and IQ on economic small-world properties and regional nodal properties of the functional brain networks. At a global level of whole networks, we found significant age-related increases in the small-worldness and local efficiency, significant higher values of the global efficiency in boys compared with girls, and no significant IQ-related difference. Age-related increases in the regional nodal properties were found predominately in the frontal brain regions, whereas the parietal, temporal, and occipital brain regions showed age-related decreases. Significant sex-related differences in the regional nodal properties were found in various brain regions, primarily related to the default mode, language, and vision systems. Positive correlations between IQ and the regional nodal properties were found in several brain regions related to the attention system, whereas negative correlations were found in various brain regions primarily involved in the default mode, emotion, and language systems. Together, our findings of the network topology of the functional brain networks in healthy children and its relationship with age, sex, and IQ bring new insights into the understanding of brain maturation and cognitive development during childhood and adolescence.

Community structure is a universal and significant feature of many complex networks in biology, society, and economics. Community structure has also been revealed in human brain structural and functional networks in previous studies. However, communities overlap and share many edges and nodes. Uncovering the overlapping community structure of complex networks remains largely unknown in human brain networks. Here, using regional gray matter volume, we investigated the structural brain network among 90 brain regions (according to a predefined anatomical atlas) in 462 young, healthy individuals. Overlapped nodes between communities were defined by assuming that nodes (brain regions) can belong to more than one community. We demonstrated that 90 brain regions were organized into 5 overlapping communities associated with several well-known brain systems, such as the auditory/language, visuospatial, emotion, decision-making, social, control of action, memory/learning, and visual systems. The overlapped nodes were mostly involved in an inferior-posterior pattern and were primarily related to auditory and visual perception. The overlapped nodes were mainly attributed to brain regions with higher node degrees and nodal efficiency and played a pivotal role in the flow of information through the structural brain network. Our results revealed fuzzy boundaries between communities by identifying overlapped nodes and provided new insights into the understanding of the relationship between the structure and function of the human brain. This study provides the first report of the overlapping community structure of the structural network of the human brain.

To determine the relationship between age and gray matter structure and how interactions between gender and hemisphere impact this relationship, we examined correlations between global or regional gray matter volume and age, including interactions of gender and hemisphere, using a general linear model with voxel-based and region-of-interest analyses. Brain magnetic resonance images were collected from 1460 healthy individuals aged 20-69 years; the images were linearly normalized and segmented and restored to native space for analysis of global gray matter volume. Linearly normalized images were then non-linearly normalized and smoothed for analysis of regional gray matter volume. Analysis of global gray matter volume revealed a significant negative correlation between gray matter ratio (gray matter volume divided by intracranial volume) and age in both genders, and a significant interaction effect of age × gender on the gray matter ratio. In analyzing regional gray matter volume, the gray matter volume of all regions showed significant main effects of age, and most regions, with the exception of several including the inferior parietal lobule, showed a significant age × gender interaction. Additionally, the inferior temporal gyrus showed a significant age × gender × hemisphere interaction. No regional volumes showed significant age × hemisphere interactions. Our study may contribute to clarifying the mechanism(s) of normal brain aging in each brain region.

Cr4+-doped crystals are promising materials for infrared solid laser applications. In order to choose proper host materials of Cr4+ from the wide variety of crystals, multiplet energy levels of Cr4+ should be evaluated without experimental information. A newly developed firstprinciples method for determining the mean-field Hamiltonian of the localized luminescent center based on quasiparticle self-consistent GW was applied to 3d² transition metal ions (Cr4+ and V3+) in α-Al2O3. Our method gave good agreement with the effective Coulomb parameters and crystal-field parameters estimated from experimental data. Multiplet energy structures were therefore well reproduced by our method. These results show the possibility of designing new laser host materials within the framework of the first-principles calculations. [ABSTRACT FROM AUTHOR]

Computational materials design (CMD) based on the first-principles electronic structure calculations is demonstrated for two topics related to the design of high-entropy alloys (HEAs). The first one is a construction of prediction model of elastic constants. By applying machine learning technique with the use of the linearly independent descriptor generation method to the database of elastic constants of 2555 BCC HEAs generated by the full potential Korringa-Kohn-Rostoker coherent potential approximation (FPKKR-CPA) method. The obtained model is used to predict new HEAs with high Young’s modulus. The second topic is a simulation of atomic arrangement in HEAs at finite temperature. In this simulation, HEAs are described by using the Potts-like model and the interaction parameters are determined based on the generalized perturbation method combined with the KKR-CPA method. Monte Carlo simulations for the models of CrMnFeCoNi and CrMnFeCoCu predict atomic arrangements which are consistent to the experimental observations. [ABSTRACT FROM AUTHOR]

CO2 methanation is a technology that produce CH4 using CO2 and H2 as raw materials through the Sabatier reaction. In the present study, the effects of temperature characteristics and CO2 conversions in the two types of catalyst reactors (i.e., granular catalyst reactor, catalyst coated reactor) were evaluated. For the catalyst coated reactor, the base substrate was formed to a circular tube composed of agglomerates of metal particles by the Additive Manufacturing method. The catalyst layer was produced by the slurry coating method. The fine particles in the slurry were obtained by pulverizing the commercially catalyst with a hammer mill. The thickness of the catalytic particle layer was increased by multiple coating process, and the catalyst base-substrate was not exposed. The temperature rise of nearly 50°C occurred in the granular catalyst reactor at a set temperature of 300°C, while in the coated catalyst reactor the temperature was almost flat along the gas flow direction. Furthermore, it was clarified that the CO2 conversions were determined by the maximum temperatures of the catalyst reactors. The proposed reactor in this study showed the possibility for solving the problem in the methanation process that is the temperature rises during the reaction. [ABSTRACT FROM AUTHOR]