The functional verification period of takes longer due to the increase of circuit scale. emulator using FPGAs is one of the fastest verification techniques.FPGA-based emulator requires a circuit partitioning when emulating a large-scale circuit.And its emulation frequency is remarkably reduced.Currently, there is no commercial FPGA-based emulator which can be implemented the circuit scale of hundreds of millions gates and exceeds the emulation frequency of 10MHz.This paper proposes the FPGA-based emulator using high-speed serial communication for data communication between the FPGAs.

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Recently, there exist great demand to develop a light insulation structure with large sound transmission loss. We have been developping an Active Sound Insulation Unit (ASIU) that consists of the Active Sound Insulation Cell (). Each is controlled as a SISO system. In the previous studies, we have developed an that consist of a flat speaker. In this paper, by changing the shape of the structure, we further try to develop an that is lighter and achieves better sound insulation performance.

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Abstract: Acid-sensitive ion channels (ASICs) are a class of cationic channels activated by extracellular acidification protons (H+), with multiple subtypes permeable to different ions.Acid-sensing ion Channel 1a (

1a) is one of the subtypes that allows Na+ and Ca2+ to flow into the cell and is expressed in inflammation, tumor and ischemic in the central nervous system and non-neuronal injury, but less reported in non-nervous systems. Endoplasmic reticulum(ER) unfolding or misfolding of protein accumulation and intracellular calcium homeostasis imbalance can lead to endoplasmic reticulum stress(ERS). In our early studies, 1a and ERS were involved in the progression of liver fibrosis, but the exact pathway involved and whether there was a link between 1a and ERS remain unkown. The purpose of this study was to explore the role of 1a and ERS in the progression of hepatic fibrosis and the interaction between them. Results showed that the expression of 1a and ERS-related proteins were increased in liver fibrosis and PDGF-BB induced HSCs, and there was potential link between them, which affected the ERS downstream pathway IRE1-XBP1. 1a, stimulated by PDGF-BB, migrated to the cell membrane and activated, caused extracellular calcium influx, which can be regulated by PI3K / AKT pathway. 1a activation induced calcium influx made intracellular calcium homeostasis changes, induced endoplasmic reticulum stress and IRE1-XBP1 pathway activation.

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This paper describes designs of structures and control systems of an active sound insulation unit consisting of active cells which are individually controlled as a single input single output system. Two types of Active Sound Insulation Cell () using lightweight card-type speakers were manufactured for trial. It became clear that can reduce the transmitted noise whose sound field inside the cell is uniform. That means that the size of should be less than quarter wavelength of controlled sound and secondary noise sources should be properly arranged. The feedback control system for ANC was systematically designed by H-infinity control theory, and the sound attenuating performance was verified by the simulation.

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LSIは, 集積度の向上によりシステムに近い機能をもつようになり, その用途は特定な機器に限られる傾向にある.このLSIをと呼び, 種々の開発手法が提案されている.技術についてそれぞれの特徴を解説する.

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The airway epithelium is exposed to an acidic environment in certain conditions. The acid-sensing ion channel 2 (2) belongs to the epithelial amiloride-sensitive sodium channel and degenerin (ENaC/DEG) family and is expressed on cilia of the respiratory epithelium. The aim of this study was to detect the expression of 2 in the nasal septum in the embryonic stage of the rat. 2 expression was not observed in the primary cilium but was found in some cilia on embryonic day 17 (E17). After E18, all cilia showed 2 immunoreactivity. RT-PCR analysis revealed that 2b, a subtype of 2, was expressed in the nasal septum while 2a was not. Quantitative Real-time RT-PCR studies indicated that the expression level of 2 mRNA was highest on E21, just before birth. These results imply that 2 plays little part in the development of the nasal septum epithelium. On the other hand, 2, especially 2b, may function for the survival and retention of ciliated cells of the nasal septum against dynamic changes in the pH environment at birth.

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Taste receptor cells detect gustatory stimuli using a complex arrangement of ion channels, G protein-coupled receptors, and signaling cascades. Sour and salty tastes are detected by ion channels in the rat. Using a combination of homology screening and functional expression approaches, we screened a rat circumvallate papilla cDNA library and identified acid-sensing ion channel-2a (2a) and 2b as candidates for the rat sour-sensing channels. In situ hybridization and reverse transcription-polymerase chain reaction experiments revealed that 2a and 2b transcripts were localized in taste bud cells. Immunohistochemistry and immunoprecipitation also revealed that both subunits were expressed in a subset of taste cells and that some of the cells expressed 2a/2b heteromeric assemblies. Electrophysiological studies demonstrated that stimulation of acetic acid produced larger 2 currents than did hydrochloric acid at the same pH. 2a/ 2b channels generated maximal inward currents at pH ≤ 2.0, which agrees well with the in vivo pH-sensitivity of rat taste cells. The amiloride-sensitivity of 2a/ 2b heteromer lessened with decreasing pH and almost completely disappeared at pH 2.0. These data suggest that 2a and 2b may play roles in sour taste transduction.

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Acid sensing ion channel 3 (3) is highly expressed on the cardiac afferents and has been proposed to transduce the tissue acidification caused by myocardial ischemia into electrical signals leading to chest pain (angina). However, this proposal requires that 3 has certain kinetic properties. Occlusion of a coronary artery for several minutes decreases myocardial tissue pH just to ∼7.0 or 6.7 at the lowest. Thus, the acid sensor must respond within this critical range of extracellular pH. Furthermore, 3 channels desensitize, whereas the chest pain is persistent. Here we show that the small changes in pH do indeed trigger sustained 3 current associated with persistent neuronal excitation expected during angina. Successive 20-sec step changes in pH between 7.4 and 6.7 produced the sustained Na⁺-selective current in 3-transfected CHO cells. The peak magnitude of the sustained current occurred at pH 7.0. The bell-like shape of the I-pH relationship suggests that the sustained 3 current is a 'window current', caused by overlap of activation and desensitization curves. Lactate, an anaerobic metabolite, enhanced the sustained current at pH 7.2 and 7.1, but not at pH 7.0-6.8. Thus, 3 has appropriate properties to trigger lactic acid-induced nociception during cardiac ischemia. When 3 is co-expressed with 2a, the activation curve shifts to more acidic pH. Thus, the presence of homomers and heteromers of 3 channels provides a cell the ability to generate prolonged current in response to a range of pH below 7.2. [Jpn J Physiol 55 Suppl:S10 (2005)]

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Background: The mechanically sensitive volume receptors, primarily located in the venoatrial junction area, are essential for blood volume homeostasis. However, the molecular basis of the volume receptors is still unknown. Methods and Results: We hypothesized that the acid-sensing ion channel 3 (3) might be a candidate for the mechanically sensitive molecules expressed in the volume receptors. We examined the effect of null mutation (-/-) on blood volume expansion (BVE)-induced urine flow, neural activation, and atrial natriuretic peptide (ANP) release in mice. BVE-induced urine flow was lower in -/- mice than in wild-type littermates. In addition, the stretch-activated channel blocker GdCl₃ further reduced the BVE-induced urine flow in -/- mice. BVE increased phosphorylated extracellular signal-related kinase (pERK) immunoreactivity in nodose ganglia and many segments of dorsal root ganglia (DRG) in all mice, but pERK-positive neurons were fewer in -/- mice or mice pretreated with GdCl₃ than in wild-type mice. knockout selectively decreased BVE-induced pERK-immunoreactive neurons in nodose ganglia, and in C8 and T2 DRG. Moreover, BVE increased the circulating ANP level, which was abolished in -/- mice and wild-type mice treated with GdCl₃. knockout reduced the BVE-induced plasma ANP elevation in a GdCl₃-independent manner. Conclusions: 3 is a molecular substrate involved in detecting the vessel stretch caused by BVE. (Circ J 2011; 75: 874-883)

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Background: Cardiac angina is the hallmark of myocardial ischemia, but the role of the cardiac sensory nerve has received relatively little attention. Recently, both acid-sensing ion channel 3 (3) and capsaicin receptor (TRPV1) have been suggested as important mediators in sensing cardiac ischemia. However, studies comparing the physiological roles of 3 and TRPV1 in the neuronal-cardiac sensing circuits in vivo are lacking. Methods and Results: Isoproterenol (1.5mg/kg, intraperitoneally) was used to induce transient cardiac ischemia in +/+ and -/- mice and a radio-telemetry system was used for electrocardiography with mice in a conscious state. Isoproterenol-induced cardiac ischemia was first demonstrated with ST-segment depression and further confirmed by hypoxia-mediated chemical reactions in cardiac tissue. Mice lacking

Asic

3 showed prolonged duration of ST-segment depression compared with +/+ mice (44.3±3.1 vs. 31.7±2.9min; P<0.05). Although ischemia was transient, severe cardiac fibrosis was found in -/- but not in +/+ mice littermates. In contrast, isoproterenol-injected Trpv1^+/+ and Trpv1^-/- mice showed no difference in duration of ST-segment depression and, surprisingly, deletion of Trpv1 did not aggravate cardiac fibrosis. Conclusions: An isoproterenol-induced cardiac ischemia model mimicking clinical conditions of early cardiac angina was used to demonstrate that 3 but not TRPV1 plays a protective role in sensing cardiac ischemia. (Circ J 2011; 75: 174-178)

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中性子星連星の衝突・合体は重力波とX線を同時に放出すると考えられている。2018年頃から世界中で本格的に稼働し始める重力波観測と同期した観測により候補天体の同定をするために、広視野X線撮像検出器を開発している。広視野X線撮像検出器はストリップ型半導体検出器(SSD)と高利得アナログ集積回路(

)が一体となっている。本研究では様々な電極幅のSSDを開発し、電極幅の最適化を行った。また、の性能評価、開発中である3号機の開発状況について報告する。

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Time over Threshold(ToT)法は簡便に波高値をパルス幅として計測することができるため、などと組み合わせて有用な手法であるが、従来のToT法では、リニアリティに問題があった。本研究では信号の閾値を信号検出とともにスイープする新しい方式を考案した。

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We designed and evaluated ASICs (Application Specific Integrated Circuits) for the human activity monitoring systems to reduce the total power consumption. The extracts the heart rate from measured ECG (Electrocardiogram) raw signal. To realize the with ultra-low power consumption, we used novel algorithm based on fuzzy logic which is very simple and light processing. The fabricated shows sufficient function and low power as low as 2 µW.85% of the power consumption for MPU (Micro-Processing Unit) processing was cut by using the heart rate extraction .

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We have been studying the via-programmable structured architecture "VPEX3 (Via-Programmable logic using EXclusive-or array 3)", which can realize arbitrary logic by customizing only via layers. Our previous research found that VPEX3 cannot achieve the same maximum operation speed as and other mask-programmable devices. In this paper, we propose and evaluate a new architecture "VPEX3S". In this architecture, the output drivability of LEs is strengthened, and the via resistance between LEs is reduced in order to decrease the critical path delay. From an evaluation using logic synthesis, maximum operating speed of VPEX3S was found to be improved by about 34% compared to VPEX3. On the other hand, the circuit area was estimated to be 50%-60% larger than that of VPEX3 from the logic synthesis result. This is because the LE size increased by a factor of 1.85 because of the increase in transistor gate width and the number of vias. However, after placing and routing, the implementation area was estimated to be comparable or smaller. This is because the number of routing resources determines the area. As a result, the proposed architecture VPEX3S can realize the same speed performance as ASICs, with 3.3-4 times larger implementation area.

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Micro-magnetometers with low-noise digital output are extensively utilized in both military and civilian applications. In this work, we propose a method that combines chopping modulation technology with interface

design to effectively attenuate low-frequency 1/f noise. Magnetic shielding and chopping modulation are applied to tunneling magnetoresistance (TMR) sensors. The high-precision interface incorporates a ripple reduction circuit and utilizes a switched-capacitor sigma-delta topology. The chip for the TMR magnetometer was fabricated using a 0.35 μm CMOS process provided by Shanghai Huahong company. The active area of the interface is 3.2 mm × 3 mm. For testing, the interface chip, which includes a three-channel sigma-delta ADC, was integrated with the TMR sensor on the same PCB. The TMR sensor and operate with a total power consumption of 27 mW under a single 5 V power supply. The integrated TMR sensor system achieves a resolution of 260 pT/√Hz across the signal bandwidth, with a nonlinearity of 0.11% and an input range of ±100 μT.

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Two new multiplexing modules have been proposed for large multi-channel front-end and 2 prototype have been designed. Although dead time exists for multiplexing method, multiplexing methods improve design efficiency without scarifying performance. The multiplexing methods are expected to be applied for both analog and mixed-signal circuits.

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