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In evaluating the wind response of base-isolated buildings, it is important to consider not only along-wind load but also the across-wind and the torsional wind loads. It is also known that devices using lead or tin with creep potential can be considered unable to resist mean wind force. In this paper, a simple evaluation method for the wind response of base isolated buildings is proposed considering the combination of equivalent static wind loads with creep potential.

In general, eigenvalue analysis for beams considering rotatory inertia and shear deformation is not trivial, even in the case of uniform beams. In this paper, a practical method is proposed for calculating natural bending frequencies of uniform elastic beams considering rotatory inertia and shear deformation. The proposed method is based on the modified Timoshenko beam theory, which is more rigorous and realistic than the traditional Timoshenko beam theory. It is shown that the proposed method calculates the natural frequencies of an arbitrary order-vibration mode for beams of arbitrary cross-sections with a high level of accuracy, similar to numerical analysis.

Although the short- to medium-term efficacy of Gamma Knife therapy for drug-resistant essential trigeminal neuralgia has been reported, long-term evaluations are limited. We evaluated patient data obtained at least 10 years post-treatment and examined the significance of this treatment using new endpoints.Among 249 consecutive patients with essential trigeminal neuralgia who were treated with Gamma Knife radiosurgery (retrogasserian target/4-mm single isocenter/90 Gy at 100%) at our institution between January 2003 and October 2011, 103 patients who were followed up for at least 10 years (mean, 174 [120-219] months) after treatment and whose data were amenable to accurate evaluation, were included in this retrospective study. Herein, we used the Barrow Neurological Institute pain intensity (BNI-P) scale as a clinical evaluation method for pain and the BNI-numbness scale (BNI-N) to evaluate complications (namely facial dysesthesia).The initial and final follow-up pain attack cessation (BNI-P score Ⅰ-Ⅲa) rate was 82.5% (85/103) and 58.2% (60/103), respectively. Furthermore, sensory impairment (BNI-N score ≥ II) at the last follow-up was observed in 24.3% (25/103) of the cases, while very bothersome status (BNI-N score IV) was observed in 2.9% of the cases.Gamma Knife radiosurgery for essential trigeminal neuralgia showed good therapeutic effects during long-term follow-up. Serious complications of significant concern in the short- to mid-term follow-up, resolved spontaneously. Therefore, the indications for treatment should be expanded to include patients who strongly desire Gamma Knife therapy.

Active base isolation has been studied in the last few decades to improve the control performance of base isolation. As a two-degree-of-freedom active disturbance-rejection method, the equivalent-input-disturbance (EID) approach shows its validity for structural control. It uses a state observer to estimate the effect of disturbances on a control input channel. However, since the model of a base-isolated building has high degrees-of-freedom, the resulting control system has a high order. Thus, the use of a full-order state observer results in the complexity of a control-system implementation. To solve this problem, this paper presents an EID control system that uses a reduced-order state observer (ROSO) to reduce the expense of control-system implementation and ensure system reliability. First, the condition of using an ROSO in an EID control system is derived, and the configuration of an ROSO-based EID control system is presented. Next, the concept of perfect regulation is used to design the gain of the state observer. A stability condition of the system with prescribed control performance is derived in the form of a linear matrix inequality (LMI) that is used to design the gain of the state feedback. Finally, the seismic control of a base-isolated building demonstrates the validity of the method.

The active structural control (ASC) has been applied to base-isolated buildings to achieve a high-damping system. The critical step for designing an ASC system is selecting control parameters and isolation parameters that satisfy the design restrictions. However, the conventional methods are limited in theoretically estimating the maximum control force, which requires great demand for trial-and-error approaches and numerical simulations. This paper constructed the equivalent model of the feedback control system that theoretically expresses the dependence of vibration characteristics (natural period and damping ratio) of the control system on the feedback gain. Then, the control-force spectrum is proposed that estimates the maximum control force for a feedback control system, adjusting both the natural period and damping ratio of the control system. The maximum responses and control force are estimated without additional numerical simulations and trial-and-error approaches using the equivalent model and control-force spectrum. Moreover, a design method was devised for determining the allowance range of the vibration characteristics of structures (damping ratio and natural period) and controllers that satisfy the design limitations (maximum responses and maximum control force). The design method does not require trial-and-error and numerical simulations, thus simplifying the design procedure. Finally, this paper uses numerical examples and a design example to verify the validity of the control-force spectrum and design method.

Active control has been applied to base-isolated buildings to achieve high control performance. A base-isolated building with active control has many design parameters, such as parameters of the superstructure, isolator, viscous dampers, and hysteretic dampers. The conventional control-system design uses trial-and-error approaches to select these design parameters and numerical simulations to estimate the responses of the system, causing a limited design outlook. In this study, we presented a spectrum-based design method for active base-isolated buildings with both viscous and hysteretic dampers for selecting the parameters of the isolator, viscous damper, steel hysteretic damper, and controller. The presented method estimates the maximum responses and maximum control force of the control system only using response spectra of the design earthquake wave, thus eliminating trial-and-error approaches and numerical simulations. Numerical design examples were also used to show the details of the design procedure and the validity of the presented method.

This paper presents a new design method based on a robust-control strategy in the form of a linear matrix inequality (LMI) approach for a passive tuned mass damper (TMD), which is one of the common passive-control devices for structural vibration control. To apply the robust control theory, we first present an equivalent expression that describes a passive TMD as an active TMD. Then, some LMI-based condition is derived that not only guarantees robust stability but also allows us to adjust the robust H∞ performance. In particular, this paper considers the transfer function from a seismic-wave input to structural responses. Unlike other methods, this method formulates the problem to be a convex optimization problem that ensures a global optimal solution and considers uncertainties of mass, damping, and stiffness of a structure for designing a TMD. Numerical example uses both a single-degree-of-freedom (SDOF) and 10DOF models and seismic waves. The simulation results demonstrated that the TMD that is designed by the presented method has good control performance even if the structural model includes uncertainties, which are the modeling errors.

Intramolecular S-acylation of a thiol-installed threonine with a thioester unit, followed by S–O acyl transfer and subsequent desulphurisation, allows the synthesis of lactone peptides. A protocol has been developed enabling the cyclisation of a linear peptide, a reaction which has not been achieved by conventional methods.

The photocurrent from a semiconductor photocathode with a negative-electron affinity surface can be arbitrarily controlled by the excitation laser power. Applying this characteristic to a scanning electron microscope allows the probe current to be arbitrarily controlled at any location on the sample. A photocathode with a fast time response is required to control the probe current at high speed. This study used an InGaN photocathode for pulsed electron beam generation and investigated its time response. A pulsed electron beam with 3.8 ns pulse width and 8.1 × 103 A cm−2 current density was observed, and the rise and fall times of the photocurrent were found to be 1.7 and 2.0 ns, respectively. The results show that despite the bottleneck of the time response of the laser power, the InGaN photocathode generates an electron beam that can control the probe current on a pixel-by-pixel for a 270 MHz scan speed.

Pulsed electron beams from a photocathode using an InGaN semiconductor have brought selectively scanning technology to scanning electron microscopes, where the electron beam irradiation intensity and area can be arbitrarily selected within the field of view in SEM images. The p-type InGaN semiconductor crystals grown in the metalorganic chemical vapor deposition equipment were used as the photocathode material for the electron beam source after the surface was activated to a negative electron affinity state in the electron gun under ultrahigh vacuum. The InGaN semiconductor photocathode produced a pulsed electron beam with a rise and fall time of 3 ns, consistent with the time structure of the irradiated pulsed laser used for the optical excitation of electrons. The InGaN photocathode-based electron gun achieved a total beam operation time of 1300 h at 15 μA beam current with a downtime rate of 4% and a current stability of 0.033% after 23 cycles of surface activation and continuous beam operation. The InGaN photocathode-based electron gun has been installed in the conventional scanning electron microscope by replacing the original field emission gun. SEM imaging was performed by selective electron beaming, in which the scanning signal of the SEM system was synchronized with the laser for photocathode excitation to irradiate arbitrary regions in the SEM image at arbitrary intensity. The accuracy of the selection of regions in the SEM image by the selective electron beam was pixel by pixel at the TV scan speed (80 ns/pix, 25 frame/s) of the SEM.

The dependence of the electron emission current density on the excitation power density of a Cs/O-activated negative electron affinity (NEA) InGaN photocathode was investigated. The emission current density of the NEA-InGaN photocathode increased monotonically with the excitation power density in the measured range. The emission current density reached 5.6 × 103 A/cm2 at an excitation power density of 2.6 × 106 W/cm2. Using the electron thermal energy estimated by comparing simulation and experimental results [D. Sato, H. Shikano, A. Koizumi, T. Nishitani, Y. Honda, and H. Amano, J. Vac. Sci. Technol. B 39, 062209 (2021)], the reduced brightness of 4 × 108 A/m2 sr V was derived.

The efficient visible light energy conversion to the electrochemical reaction system is an important challenge in the field of photoelectrochemistry. The visible light driven hydrogen evolution reaction can be recognized as one of the important targets. Recently, the introduction of the plasmonic metal nanostructures into the semiconductor electrodes has been received much attention because the system which is recognized as the plasmonic photoconversion electrode realizes the visible light response characters. Although various systems have been achieved both the cathodic and anodic reactions through the selection of the materials, the molecular process or charge transfer process have not been fully understood yet. In this study, we have proposed the plasmonic cathode system by combining the p-type semiconductor electrode with the plasmonic nanostructures and examined the both the electron transfer process.We have confirmed the unique isotope effects which cannot be observed the conventional cathode system, reflecting novel characteristics of molecular process at the plasmonic cathodes.

A wireless power transfer (WPT) circuit was developed for an inorganic electro-luminescent (EL) device. When transmission and receiver circuits are both in resonant mode, low operating voltage of 30 V was enough to achieve the EL luminance as high as 180 cd m−2. As for the transmission and the receiver coils, different types and shapes are studied to clarify those effects on the EL luminance and transmission efficiency. Solenoid coils generally presented higher luminance than other types. Polygonal solenoid coils resulted in even higher luminance and transmission efficiency than circular solenoids. A spiral or a spider coil, in which air core area is much smaller than the solenoid coil, was found to be less sensitive to coil displacement. The difference in EL performances with the variation of coils suggests the possibility of further improvement the WPT system.

Background and Aims Lymph node recurrence (LNR) after endoscopic resection (ER) in patients with esophageal squamous cell carcinoma (ESCC) invading the muscularis mucosae (pMM) without lymphovascular invasion (LVI) has been reported as non-negligible in the ER guidelines for esophageal cancer by the Japan Gastroenterological Endoscopy Society. However, these data were not regarded as high-level evidence because several retrospective case series were tabulated without sufficient long-term follow-up. Hence, this guideline stated that the administration of additional treatment after ER could not be determined for this population. This study aimed to clarify the long-term clinical outcomes after ER of pMM ESCC without LVI. Methods Between January 2009 and November 2017, we enrolled followed-up patients who underwent ER and were pathologically diagnosed with pMM ESCC without LVI without additional treatments. We retrospectively investigated the cumulative recurrence rate and recurrence-free, overall, and disease-specific survival at 5 years after ER. Results Eighty-seven patients were enrolled. During the median follow-up period of 64 months (range: 12–117), 3 patients developed lymph node and/or distant recurrence, and 2 of these cases occurred more than 3 years after ER; all 3 patients died of the primary disease. The 5-year cumulative recurrence rate was 4.3%, and the 5-year recurrence-free, disease-specific, and overall survival rates were 88.8%, 98.2%, and 91.7%, respectively. Conclusions The long-term outcome for patients with pMM ESCC without LVI was favorable after ER; however, this population had a risk of recurrence directly leading to death. Long-term follow-up is necessary, with attention to the timing of recurrence.