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Objective Acoustic therapies including hearing aids and tinnitus control instruments are widely used in Japan but without high levels of evidence. The outpatient hearing aid clinic at our institution fits patients with hearing aids and instructs patients on how to use them to control tinnitus if present. In this study, we examined the effects of this approach on tinnitus. Methods One hundred and eleven of 138 patients who visited our hearing aid clinic from April 2016 to September 2018 purchased hearing aids after fitting. Sixty-six of these patients (31 men, 35 women; mean age 78.0 ± 8.0 years) had both hearing loss and tinnitus and were enrolled. The tinnitus was bilateral in 41 patients and unilateral in 25 (poor hearing ear, n = 16, good hearing ear, n = 9). Hearing aids were worn bilaterally by 23 patients and unilaterally by 43 (89 devices). Seventeen of the 23 patients wearing bilateral hearing aids had bilateral tinnitus and 6 had unilateral tinnitus, i.e., in 40 ears, the tinnitus side matched the hearing aid side (40 devices) and in 6 ears did not (6 devices). Twenty-four of 43 patients wearing unilateral hearing aids had bilateral tinnitus, meaning that in 24 ears the tinnitus side matched the hearing aid side (24 devices). In six of the remaining 19 cases with unilateral tinnitus, the hearing aid and tinnitus were on the same side (6 devices) and in 13 were on opposite sides (13 devices). Changes in the Tinnitus Handicap Inventory (THI), visual analog scale (VAS, for tinnitus discomfort, severity, and persistence), and Hospital Anxiety and Depression Scale scores were measured immediately before using a hearing aid and 12 months later. Results Significant effects of hearing aids on tinnitus were observed in all subjects (THI, p = 0.0000030), VAS (severity, p = 0.000000066; discomfort, p = 0.0000013). Significant effects were observed with bilateral hearing aids (THI, p = 0.0012; VAS for severity, p = 0.00069; VAS for discomfort, p = 0.00052) and with unilateral hearing aids (THI, p = 0.00055; VAS for severity, p = 0.000034; VAS for discomfort, p = 0.00007). Spearman's rank correlation coefficient showed a significant positive correlation between the THI and VAS scores (p = 0.0033). In cases of bilateral tinnitus, significant differences were observed with bilateral hearing aids (THI, p = 0.011; VAS for severity, p = 0.0019; VAS for discomfort; p = 0.020) and with unilateral hearing aids (THI, p = 0.00069; VAS for severity, p = 0.00071; VAS for discomfort, p = 0.000093). Conclusion Acoustic therapy using hearing aids was effective for tinnitus. Even when bilateral, a unilateral hearing aid is able to improve tinnitus. When unilateral, the ipsilateral hearing aid is able to improve tinnitus.

We have demonstrated that sub-10 nm-thick heteroepitaxial Ge films on Si (001) having smooth surfaces can be obtained by DC magnetron sputtering. Ge films grown at 350 °C preserve the smooth surfaces with a roughness root mean square (RMS) of 0.39 nm, whereas, the Ge films grown at 500 °C show significant roughness with an island-like morphology. In samples grown at 350 °C, it is confirmed that the Ge films are grown epitaxially by cross-section transmission electron microscopy (TEM) and X-ray diffraction (XRD) rocking curve measurements. Rapid thermal annealing (RTA) at 720 °C is effective in improving the crystalline quality and the degradation in the roughness is negligible. Raman spectra and an XRD reciprocal space map reveal that the epitaxial Ge grown at 350 °C show an in-plane compressive strain and that the strain continues to remain after a 720 °C RTA.

The influence of extension doping on parasitic resistance and its variability has been investigated for FinFETs. Electrical characterization of FinFETs and crystallinity evaluation of the doped fin structure are carried out for different fin thicknesses and different donor species for ion implantation, i.e., As and P. Reducing the fin thickness and the use of donor species with a larger mass cause serious degradation in the variability and median value of the parasitic resistance. Crystallinity evaluation by transmission electron microscope reveals that significant crystal defects remain after dopant activation annealing for the cases of smaller fin thickness and the implanted dopant with a larger mass. The unrecovered defects cause serious degradation in the parasitic resistance and its variability.

A linearly polarized hard X-ray photoemission system has been developed for studying the ground-state symmetry of strongly correlated materials., An angle-resolved linearly polarized hard X-ray photoemission spectroscopy (HAXPES) system has been developed to study the ground-state symmetry of strongly correlated materials. The linear polarization of the incoming X-ray beam is switched by a transmission-type phase retarder composed of two diamond (100) crystals. The best value of the degree of linear polarization was found to be −0.96, containing a vertical polarization component of 98%. A newly developed low-temperature two-axis manipulator enables easy polar and azimuthal rotations to select the detection direction of photoelectrons. The lowest temperature achieved was 9 K, offering the chance to access the ground state even for strongly correlated electron systems in cubic symmetry. A co-axial sample monitoring system with long-working-distance microscope enables the same region on the sample surface to be measured before and after rotation. Combining this sample monitoring system with a micro-focused X-ray beam by means of an ellipsoidal Kirkpatrick–Baez mirror (25 µm × 25 µm FWHM), polarized valence-band HAXPES has been performed on NiO for voltage application as resistive random access memory to demonstrate the micro-positioning technique and polarization switching.

Objectives Hearing loss is a serious problem in infants and children because it may interfere with the development of typical speech, verbal language, and auditory and communication skills. By measuring hearing ability (thresholds) as early as possible, even as early as during infancy, effective treatment can be administered. These treatments may significantly reduce the handicap associated with hearing loss. However, at times during behavioral auditory tests, observers cannot determine whether or not an accurate threshold was obtained. To support the use of infant audiometry for accurate diagnosis, audiologic behavioral responses may be obtained by selecting stimuli that interest infants, e.g., their mothers’ voices. Methods We evaluated 30 infants who were presented to our hospital for behavioral auditory assessment in 2016. The infants' ages ranged from 4 months to 3 years and 6 months. The mean age was 1 year and 10 months ±10 months (±standard deviation). The infants' hearing thresholds for their mothers' voices and warble tones at 250–4000 Hz were measured. Auditory brainstem response (ABR) had already been evaluated in 24 infants. Relationships between mother's voice and warble tone or ABR thresholds as well as responses to the initial stimuli and stimuli at the threshold were investigated. These responses were classified into four grades (no response, uncertain response, possible positive response, and positive response), and the response to mother's voice and warble tone were subsequently compared. Results Mother's voice thresholds significantly correlated with all warble tone thresholds. In the relationship between the mother's voice threshold and average hearing levels of 500, 1000, and 2000 Hz, two infants were outliers. In these infants, the average hearing levels were relatively higher than the mother's voice thresholds. Judging from their ABR thresholds, the mother's voice thresholds were valid and the average hearing levels were worse than their original assessed hearing ability. The responses to mothers' voices were more distinct than those to warble tones, both for initial stimuli presentation and the determined threshold. Conclusions Audiologic behavioral responses to mothers' voices were clearer than those for warble tones. Evaluations that use the mother's voice threshold are useful for estimating hearing levels in infants.

Network security incident (network incident) is an important topic in the around world. Network operators and security vendors tackle these network incidents consist of many cyber crimes. The types of threats are DDoS, phishing, malware, vulnerability attacks to take control a device, and extortion case. Network operators consider protecting their environment from threats. They have to observe a trend of threat, then could trace suspicious network traffic flows on what network. Some organization and individual persons publish open security information related to past a network incident. In order to identify which network covers on suspicious activity, we collect open security information as the dataset to analyze these for providing a summary of network operators' IP addresses lead to network incident. The result is not only useful information to get a trend of threat pattern, but also we quickly handle a countermeasure to it when real network incident has happened in their environment. In the evaluation, we verify the result of proposed framework could handle the trend of network incident cases. We determine the result whether provides security threat or not based on security vendors reports. The evaluation result shows the proposed framework could identify the SSH brute force attack and other attacks before the security vendor discloses it. It is useful for supporting of network operators and community to observe the latest network incident when it occurs in their environment.

At the second postoperative year, there were no significant differences between results for vertigo and hearing after endolymphatic sac drainage with steroid instillation surgery (EDSS) and EDSS with posterior tympanotomy with steroids at the round window (EDRW). In particular, as regards hearing recovery to the preoperative level, the periods after EDRW were shorter than those after the second EDSS.Patients sometimes faces recurrent problems years after EDSS due to endolymphatic sac closure and/or disease progression. In the present study, we examined the effects of EDRW on vertigo and hearing after revision surgery for intractable relapsed Meniere's disease.Sixteen patients with Meniere's disease had revision surgery due to intractable recurrence of disease, and were followed up regularly at least for 2 years. As revision surgery, EDSS was performed repeated in eight cases and EDRW was performed in the other eight. There were no significant differences between the patients' backgrounds in the two groups.Periods of hearing recovery to the preoperative level were 11.5 ± 4.4 months after the first EDSS, although it took 16.4 ± 2.6 months longer after revision surgery with the second EDSS (p = 0.0380.05: first EDSS vs second EDSS) and was 10.0 ± 3.3 months shorter after revision surgery with EDRW (p = 0.0100.05: second EDSS vs EDRW).

A resistance random access memory (ReRAM) is expected to be a next-generation nonvolatile memory because of its fast switching speed, and low power consumption. The device structure is composed of an oxide layer sandwiched with two metal electrodes. ReRAM exhibits repetitive transition between high resistance state (HRS) and low resistance state (LRS). It is considered that resistive switching phenomenon is caused by the formation and rupture of the conductive filament formed in the oxide layer. In this study, we investigated HfOx thickness dependence of current-voltage characteristics for Ni/HfOx/Pt ReRAM device. We fabricated Ni/HfOx/Pt devices with a simple crossbar structure. HfOx layer was deposited on the Pt bottom electrode by DC reactive sputtering. The I-Vcharacteristics were measured by two-probe method at room temperature. Red line in Figure 1 shows I-V characteristics of the Ni/ HfOx/Pt device with oxide thickness of 5.6 nm. Initial state of resistance is HRS. SET process (from HRS to LRS) took place at 2.4 V with a current compliance of 0.1 mA. RESET process (from LRS to HRS) occurred at -1.6 V. The resistance ratio of HRS to LRS is about 107 with 0.1 V readout bias. On the other hand, blue line shows the I-V characteristics of the Ni/ HfO2/Pt device with oxide thickness of 4.0 nm. Initial state of resistance is LRS. Forming process was not observed in this device. SET process took place at 1.0 V. RESET process was observed at -0.6 V. Switching voltage of this device is smaller than the former device with the thicker oxide layer. The resistance ratio of HRS/LRS is about 101 with 0.1 V readout bias. There was a significant difference in switching properties between these devices whose oxide thicknesses differ only 1.6 nm. It is suggested that leakage current increases when the oxide thickness decreases, thereby the on-state occurred initially for the device with 4.0 nm oxide. It should be noted that I-V characteristic is symmetrical for the device with 4.0 nm oxide, while it is asymmetrical for the device with 5.6 nm oxide. This suggests the mechanism of conductive filament formation and rupture is completely different between these devices. Further discussions and analysis will be presented in the symposium.

The electric conduction mechanism of electrochemically treated anodic porous alumina (APA) resistance switching (RS) memory is investigated. The current-voltage characteristics of the APA were measured for both of high resistance state and low resistant state at room temperature. The conduction mechanism of a high resistance state can be explained by separating into three regions of Ohm's law, space charge limited current (SCLC), and Fowler-Nordheim (F-N) tunneling. It was suggested that the F-N tunneling decreases the reproducibility of switching voltages.

We improved the performance of a complementary circuit comprising Si-based tunnel field-effect transistors (TFETs) by using isoelectronic trap (IET) technology. IET technology was found to increase the ON current (I ON ) 5 times in P-TFETs and 2 times in N-TFETs. The ION enhancement improved the inverter performance. In addition, ring oscillator (RO) circuit operation with the complementary TFET inverters was experimentally demonstrated for the first time. The RO circuit with IET-TFETs exhibited a higher operation frequency than that with conventional TFETs. IET technology provides a breakthrough towards realizing complementary circuits with Si-TFETs.

We have studied variation of switching voltage of resistive random access memory (ReRAM). Basically, the switching voltage at every switching has a different value because there are many conduction paths, which are randomly chosen at every switching with different conductivity in an oxide insulator between top and bottom electrodes. Limitation of the number of conductive paths is expected to lead the suppression of the variation of switching voltage. In this study, Ni nanorods buried into the nanoholes of an anodic aluminum oxide (AAO) film have been fabricated to restrict the formation of many filaments and the switching behaviors of the In/NiO/Ni nanorods has been investigated.

We have demonstrated the operation of a CMOS inverter consisting of Si tunnel FinFETs. Both p- and n-type tunnel FinFETs are successfully fabricated and operated on the same SOI wafer. The current mismatch between p- and n-type tunnel FETs is compensated by tuning the number of fin channels. Very low short-circuit current and clear voltage input–output characteristics are obtained. The thin epitaxial channel in the tunnel FinFETs effectively increases the drain current and accordingly reduces the drain capacitance, which could help high-performance tunnel FET CMOS inverter operation.

We structurally and electrically characterize sub-10-nm-thick heteroepitaxial Ge films on Si(001), formed by heated sputtering and subsequent rapid thermal annealing (RTA). After RTA treatment at 720 °C, we find the heteroepitaxial Ge films to have smooth surfaces with a roughness root mean square value of 0.54 nm. Raman measurement reveals that the 720 °C RTA improves the crystallinity of Ge films while maintaining abrupt Ge/Si interfaces. Cross-sectional transmission electron microscopy confirms that the 720 °C RTA step effectively reduces stacking faults and dislocations in the Ge films. The Richardson plot of the TaN/Ge/n-Si diode indicates a Schottky barrier height (SBH) of 0.33 V, which is close to the height of 0.37 V measured from the capacitance–voltage measurement. These values are reasonable compared with the reported SBH of the TaN/bulk Ge Schottky barrier diode, indicating that the method involving heated sputtering and subsequent RTA provides adequate thin Ge films for Ge/Si heterostructures.

The influence of the extension doping conditions on gate-induced drain leakage (GIDL) has been investigated to optimize fin field-effect transistors (FinFETs) for ultralow-power (ULP) applications. An increased GIDL for a smaller fin thickness and a dependence on the implanted ion species, i.e., a larger GIDL for As than for P, are recognized. These results suggest that the residual defects due to extension doping increase the GIDL, and the suppression of the defects by the optimization of the doping process is the key to the optimization of FinFETs for ULP applications.

Hydrogen anneal effects on reproducibility of the switching voltages for a resistive switching memory using anodic porous alumina have been investigated. The hydrogen anneal made the reproducibility worse.

The switching process of the conductive filament formed in Ni/HfOx/Pt resistive random access memory (ReRAM) devices were studied. We evaluated the oxide thickness dependence and temperature dependence of voltage for the Forming, Set and Reset operations for HfOx layers whose thickness are between 3.3 and 6.5 nm. The resistance of conductive filaments showed typical metallic behavior, which suggests Ni filament formation in the HfOx layer. There is a clear dependence of switching voltages for the Set and Reset processes on oxide thickness, which implies that the formation and rupture of conductive filaments occur in the entire thickness range of the HfOx layer. This finding differs from that of a previous study by Yang, which suggests the existence of a constant-thickness switching region. It is suggested that the thickness of the switching region in HfOx may be larger than 6.5 nm.

Resistive change memory has been expected to be a next generation memory due to high-speed response. However, wide variations of switching voltages are often found in the current–voltage (I–V) characteristics and hinder the practical applications. We have tried suppressing the variation by three tactics based on the filament model; confinement of conductive filaments, concentration of electric field, and preparation of many routes for conductive filaments with the same electrical properties. In this study, we have investigated the combination of concentration of electric field method and preparation of many routes for conductive filaments in the insulator by electrochemical treatment (ET) using sulfuric acid. The I–V curves depend on the ET time. The best result is obtained in the long ET time. With regards to switching voltage distribution, the combination of two methods provide better switching characters than those of single method.

An attempt to reduce the SET voltage and RESET current of resistive switching (RS) memory was made using a geometric array of nanopeak (NP) structures. Bottoms of anodic porous alumina were used to form the NP structures that act as guides for the formation of conductive filaments that effectively concentrate the electric field. Samples were fabricated with flat surfaces (FS) and with two types of NP structure with different NP pitch. The NP samples provided SET voltages less than 2 V with narrow distributions and the RESET current was lower than that with the FS sample.

We have tried suppressing variation of switching voltages which hinder the practical application of resistive switching random access memory. On the basis of a filament model, fabrication of the top electrode with small enough size against the filament size and confining the filament are thought to be the solutions. In this study, we have investigated the confinement effects on the switching voltage variations using anodic porous alumina with ordered nano holes. Variation of the voltage has a trend to reduce with enlarging the diameters of nano holes by chemical etching. The confinement is very effective to improve the reproducibility of the switching voltages.

The control of the crystal orientation and diameter of vertically grown epitaxial Si nanowires was demonstrated using a combination of a vapor–liquid–solid (VLS) growth technique and the use of an anodic aluminum oxide (AAO) template on a single-crystal Si substrate. The [100], [110], and [111] nanowires were selectively obtained by choosing the Si substrate with appropriate crystal orientation. The diameter of a Si nanowire in the AAO template could be controlled by the modification of the pore size of the AAO template with anodic voltage during anodization.

Resistance change random access memory (ReRAM) has been expected to be a next generation non-volatile memory. However, poor reproducibility of threshold voltage at which the dramatic change of the resistivity occurs hinders the practical application. We have attempted to improve the reproducibility of switching voltages using anodic porous alumina whose nanoholes are quite useful to restrict the filament forming area on the basis of the filament model. In this study, we have reported the pore size and film properties dependences of the variation width of the switching voltages. Two kinds of oxide films prepared by oxalic and sulfuric acids with two different anodic times were used as the insulating layer. Contrary to our expectation, just the sulfuric samples indicate good improvement about the switching voltages. Considering that the size of the effective contact area is not enough small against the filament size, the changing the film properties seems to be important for the suppressing the variation of switching voltages.

We have investigated the current–voltage characteristics of a resistive switching memory (ReRAM), especially the reproducibility of the switching voltage between an insulating state and a metallic state. The poor reproducibility hinders the practical use of this memory. According to a filament model, the variation of the switching voltage may be understood in terms of the random choice of filaments with different conductivities and lengths at each switching. A limitation of the number of conductive paths is expected to lead to the suppression of the variation of switching voltage. In this study, two strategies for the limitation have been proposed using an anodic porous alumina (APA). The first is the reduction of the number of conductive paths by restriction of the contact area between the top electrodes and the insulator. The second is the lowering of the resistivity of the insulator, which makes it possible to grow filaments with the same characteristics by electrochemical treatments using a pulse-electroplating technique.

From the point of view to design a practical shock-in-rotor type rotor, the quasi-axisymmetric flow in the subsonic region is considered in the case having the uniform flow with no swirl components at the inlet of rotor blades.The flow in the supersonic region is assurned to be parallel to the axis and satisfy radial equilibrium before the normal shock. The turning angle from the inlet to the normal shock is given.In this report the flow calculation is carried out by giving two conditions (1) angular spacing and (2) angular momentum in the eubsonic region and is applicable to the example with known shapes of both inner and outer casings. The results show the possibilities to design a blade passage for practical use.

A possibility of two-dimensional supersonic portion having quasi-axisymmetric flows which satisfy simplified radial equilibrium is investigated in this report. With the intension of getting a supersonic portion for practical use, the main requirements are given as follows. (1) The inlet flow is uniform and parallel to the axis. (2) The flow just before the normal shock is quasi-axisymmetric and satisfies simplified radial equilibrium. (3) The starting condition for a supersonic diffuser is satisfied between the inlet flow and the flow just before the normal shock. (4) The turning angle and the magnitude of deceleration in the supersonic portion are specified for the purpose of adequate blade thickness. The calculated examples are obtained at hub, mean and tip radii.

A method of designing latticed wing profile with prescribed velocity distribution along wing surface (not chordwise direction) is explained. Latticed wing with small pitch-chord ratio, large camber and large thickness can be treated with fair eassiness. The full paper in English will be published in "The Report of Transportation Technical Research Institute" in near future.

A method of solution for latticed wing of arbitrary profile is presented. The profile-surface is regarded as single vortex sheet, and potential theory is applied. Thus we get an integral equation concerning to the velocity potential. By successive approximation we can get the solution. High solidity, camber, thickness do not prevent the solution, and moreover it requires less labour than the methods ever presented.But the facts that we must prescribe the discharge direction, and that we must repeat the same process to get the solution with different inlet direction, are the faults of this method.

Performances of the compressor type cascade of blades with small aspect ratio AR were experimentally obtained at the center of blade span. All blades had same span of 50mm and their aspect ratio were 2.08, 1.39, 1.04 and 0.83. Stagger angle (α) was changed from 0° to 60° and attack angle (αi) from 0° to 15°. Results indicate that total pressure loss coefficient takes a minimum value at AR_??_1 irresspectively of α and αi. At αi over about 5° turning angle (e) increases and at αi=0° it decreases gradually with increasing AR. Axial velocity ratio, in the case α=0°, decreases gradually with incresing AR, and in the case α=30° it keeps almost constant value irrespectively of AR at αi=constant, but in cases α=50° and 60° it increases at αi≥5-10° with increasing AR.

Snap25(S187A/S187A) mouse is a knock-in mouse with a single amino acid substitution at a protein kinase C-dependent phosphorylation site of the synaptosomal-associated protein of 25 kDa (SNAP-25), which is a target-soluble NSF attachment protein receptor (t-SNARE) protein essential for neurotransmitter release. Snap25(S187A/S187A) mice exhibit several distinct phenotypes, including reductions in dopamine and serotonin release in the brain, anxiety-like behavior, and cognitive dysfunctions. Homozygous mice show spontaneous epileptic convulsions, and about 15% of the mice die around three weeks after birth. The remaining mice survive for almost two years and exhibit spontaneous recurrent seizures throughout their lifetime. Here, we conducted long-term continuous video electroencephalogram recording of the mice and analyzed the process of epileptogenesis and epileptic maturation in detail. Spikes and slow-wave discharges (SWDs) were observed in the cerebral cortex and thalamus before epileptic convulsions began. SWDs showed several properties similar to those observed in absence seizures including (1) lack of in the hippocampus, (2) movement arrest during SWDs, and (3) inhibition by ethosuximide. Multiple generalized seizures occurred in all homozygous mice around three weeks after birth. However, seizure generation stopped within several days, and a seizure-free latent period began. Following a spike-free quiet period, the number of spikes increased gradually, and epileptic seizures reappeared. Subsequently, spontaneous seizures occurred cyclically throughout the life of the mice, and several progressive changes in seizure frequency, seizure duration, seizure cycle interval, seizure waveform, and the number and waveform of epileptic discharges during slow-wave sleep occurred with different time courses over 10 weeks. Anxiety-related behaviors appeared suddenly within three days after epileptic seizures began and were delayed markedly by oral administration of valproic acid. These results showed that Snap25(S187A/S187A) mice exhibited a variety of epilepsy-related phenomena, and thus, they will be useful for understanding the mechanisms of epileptogenesis, epileptic maturation, and the actions of antiepileptic drugs.