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Objective: To determine the optimal montage and vocalization conditions for high-gamma language mapping using stereoelectroencephalography. Methods: We studied 12 epilepsy patients who underwent invasive monitoring with depth electrodes and measurement of auditory-naming related highgamma modulations. We determined the effects of electrode montage and vocalization conditions of the response on the high-gamma (60–140  Hz) amplitudes. Results: Compared to common average reference montage, bipolar and Laplacian montages effectively reduced the degree of auditory naming-related signal deflections in the white matter during the stimulus and response phases (mixed model estimate: −21.2 to −85.4%; p  <  0.001), while maintaining those at the cortical level (−4.4 to +7.8%; p  =  0.614 to 0.085). They also reduced signal deflections outside the brain parenchyma during the response phase (−90.6 to −91.2%; p  <  0.001). Covert responses reduced signal deflections outside the brain parenchyma during the response phase (−17.0%; p  =  0.010). Conclusion: On depth electrode recording, bipolar and Laplacian montages are suitable for measuring auditory naming-related high-gamma modulations in gray matter. The covert response may highlight the gray matter activity. Significance: This study helps establish the practical guidelines for high-gamma language mapping using stereoelectroencephalography. [ABSTRACT FROM AUTHOR]

Objective: Vagus nerve stimulation (VNS) is a palliative surgery for drug-resistant epilepsy. The two objectives of this study were to (1) determine the seizure type most responsive to VNS and (2) investigate the preventive effect on status epilepticus (SE) recurrence. Methods: We retrospectively reviewed 136 patients with drug-resistant epilepsy who underwent VNS implantation. We examined seizure outcomes at 6, 12, and 24 months following implantation of VNS as well as at the last visit to the Juntendo Epilepsy Center. Univariate analysis and multivariate logistic regression models were used to estimate the prognostic factors. Results: 125 patients were followed up for at least 1 year after VNS implantation. The percentage of patients with at least a 50% reduction in seizure frequency compared with prior to VNS implantation increased over time at 6, 12, and 24 months after VNS implantation: 28, 41, and 52%, respectively. Regarding overall seizure outcomes, 70 (56%) patients responded to VNS. Of the 40 patients with a history of SE prior to VNS implantation, 27 (67%) showed no recurrence of SE. The duration of epilepsy, history of SE prior to VNS implantation and seizure type were correlated with seizure outcomes after VNS implantation in univariate analysis (p = 0.05, p < 0.01, and p = 0.03, respectively). In multivariate logistic regression analysis, generalized seizure was associated with VNS response [odds ratio (OR): 4.18, 95% CI: 1.13-15.5, p = 0.03]. A history of SE prior to VNS implantation was associated with VNS non-responders [(OR): 0.221, 95% CI: 0.097-0.503, p < 0.01]. The duration of epilepsy, focal to bilateral tonic-clonic seizure and epileptic spasms were not significantly associated with VNS responders (p = 0.07, p = 0.71, and p = 0.11, respectively). Conclusion: Following 125 patients with drug-resistant epilepsy for an average of 69 months, 56% showed at least 50% reduction in seizure frequency after VNS implantation. This study suggests that generalized seizure is the most responsive to VNS, and that VNS may reduce the risk of recurrence of SE. VNS was shown to be effective against generalized seizure and also may potentially influence the risk of further events of SE, two marker of disease treatment that can lead to improved quality of life. [ABSTRACT FROM AUTHOR]

We propose a novel online algorithm for moving blind source extraction (BSE). The original algorithm is based on the recently proposed constant separating vector mixing model with batch auxiliary-function-based independent vector extraction (CS V-AuxIVE). The CSV-AuxIVE is not suitable for some devices that require real-time processing. In this case, we propose the online-CSV-AuxIVE, which only needs to know part of the mixed signal to process the observed signal sequentially. Then, we verified the effectiveness of the proposed method on a specific task of extracting moving two-speaker signals. In the experiment, the online-CSV-AuxIVE is compared with the online-AuxIVA. The result shows that under the same conditions of the source of interest (SOI), the average source-to-distortion ratio (SDR) of online-CSV-AuxIVE is approximately 1.5 dB higher than that of online-AuxIVA regardless of the changes in the range and speed of the interference (IR). [ABSTRACT FROM AUTHOR]

Introduction: Dual-task (DT) exercise can act as a substitute, which can help improve both physical and cognitive functions. Thus, this study investigated the effects of a game-like cognitive DT exercise called "Synapsology" (SYNAP) among the oldest residents of a nursing home. Methods: Participants (aged 85-97 years) were assigned to the intervention group (n = 12) and the control group (n = 12). The intervention group underwent 60-minute sessions, twice a week for 24 weeks. Results: A comparison of the Mini-Mental State Examination scores and six physical function tests, before and after the intervention, shows that the SYNAP had a positive impact on the cognitive and physical functions among the intervention group. Discussion: These findings suggest that SYNAP may help maintain or improve cognitive and physical functions among older adults compared to no interventions. Therefore, SYNAP would act as a beneficial tool amidst a "superaging" society like Japan. [ABSTRACT FROM AUTHOR]

The purely phase-constant-nonreciprocal composite right-left handed metamaterial structure is proposed based on coplanar waveguides loaded with a ferrite layer. The structure exhibits considerably large nonreciprocity in phase constant which depends on the effective magnetization and whose magnitude can remain in leaky wave region of wavenumbers or can overcome a boundary to slow wave region. The nonreciprocity in amplitude of transmission coefficients, on the other hand, is effectively reduced by using a cavity-backed design to prevent undesired nonreciprocal radiation loss. [ABSTRACT FROM AUTHOR]

Aim: Dual-task methods, in which walking is the primary task, are not sufficient for accurately screening for the risk of falls among healthy older adults. Therefore, the goal of this research was to investigate whether using a dual-task method over an extended walking distance can predict falls among community-dwelling older adults. Methods: We enrolled independent community-dwelling adults aged ≥65 years. Physical performance, cognitive function, psychological function, and a dual-task test were assessed at baseline. Our dual-task test required the subjects to walk 60 m while stepping over lines. The intervals between the lines ranged from 50–100 cm and were unequal. Falls and fall-related injuries were measured over a 12-month follow-up period using monthly postal surveys. Results: Ninety-two of 118 subjects (mean age, 75.4±5.5 years) completed the 12-month follow-up. Sixteen (17.4%) of fallers had injurious falls or fell more than or equal to two times. There were no significant differences between the fallers and non-fallers, except in age and in the number of missteps during the dual-task test when walking ≥40 m. The Kaplan–Meier analysis revealed that those who had more than one misstep while walking ≥40 m had a significantly higher incidence of injurious or multiple falls than those who had no missteps. Conclusion: Our findings suggest that the dual-task method with an extended walking distance may be able to predict falls among community-dwelling older adults. [ABSTRACT FROM AUTHOR]

The right temporal lobe variant of frontotemporal dementia (FTD) is an uncommon progressive neurodegenerative disorder. We present the case of a 77-year-old right-handed man who presented with altered behaviour and problems with interpersonal relationships. He had no decline in cognitive function but brain perfusion single-photon emission CT demonstrated distinct hypoperfusion in the right temporal pole. At 2-year follow-up, he could not recognise his wife's relatives; and at 3-year follow-up, he had semantic aphasia. Decreased brain perfusion extended from the right temporal lobe into the contralateral temporal and both frontal lobes. These findings suggest that the right temporal lobe variant of FTD should be considered in elderly patients with altered behaviour and problems with interpersonal relationships, even if dementia is not suspected. The right anterior temporal lobe may play a key role in the onset of the early symptoms of this disease. [ABSTRACT FROM AUTHOR]

Abstract In the present study, we aimed to establish an additional standardized protocol with a higher H. pylori eradication rate in the remnant stomach. Fifty-five H. pylori–positive patients were randomly allocated to one of three regimens: LAC—lansoprazole, amoxicillin, and clarithromycin b.i.d. for 7 days (n = 17); LAC+CET—LAC b.i.d. plus cetraxate q.i.d. for 7 days (n = 20); and LEFT—LAC for 7 days in a horizontal body position on the left side for 30 min (n = 18). Patient compliance and side effects were checked via interviews. H. pylori eradication was successful in 75, 72, and 41% in LAC+CET, LEFT, and LAC, respectively. The eradication rate was significantly higher in LAC+CET than in LAC (P = 0.024) but not in LEFT (P = 0.058). Adverse events that occurred in each group were almost all mild ones. Cetraxate plus LAC for 1 week is a safe and effective regime for the eradication of H. pylori in patients after partial gastrectomy. [ABSTRACT FROM AUTHOR]

This review introduces and overviews electromagnetism in structured metamaterials which undergo simultaneous time-reversal and space-inversion symmetry breaking due to magnetism and chirality. Direct experimental observation of optical magnetochiral effects in a single metamolecule with magnetism and chirality is demonstrated at microwave frequencies. Numerical simulations based on a finite element method reproduce the experimental results well, and predict the emergence of giant magnetochiral effects, by combining resonances in the metamolecule. Toward the realization of magnetochiral effects at higher frequencies than microwaves, a metamolecule is miniaturized in the presence of ferromagnetic resonance in a cavity and coplanar waveguide. This work opens the door to the realization of a one-way mirror and synthetic gauge fields for electromagnetic waves. [ABSTRACT FROM AUTHOR]