Search

A 26-year-old Japanese woman developed a fever, myalgia and gait disturbance one day after receiving the second dose of the mRNA-1273 severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine. A neurological examination revealed symmetrical weakness and myalgia in proximal lower limbs, and a blood examination showed prominent elevation of creatinine kinase. Magnetic resonance imaging (MRI) revealed a high signal intensity in the thigh muscles on short-tau inversion recovery images, and antibody testing revealed positive findings for anti-signal recognition particle (SRP) antibody. Thus, anti-SRP antibody-positive immune-mediated myopathy was diagnosed. We initiated immunotherapy, and she was ultimately able to walk stably.

A 70-year-old woman presented with a 6-year history of cognitive dysfunction, neurogenic bladder, constipation and recurrent vomiting, and gradual worsening of symptoms. At the first admission to our department, she was also found to have hepatic encephalopathy due to intrahepatic portosystemic shunt. Head MRI revealed abnormal signal intensity at the corticomedullary junction, the splenium of the corpus callosum, and bilateral middle cerebellar peduncles on DWI. She was diagnosed with intranuclear inclusion disease (NIID) based on skin biopsy and genetic testing of NOTCH2NLC. In a retrospective review of serial head MRI findings for ten years, abnormal signal intensity at the corticomedullary junction and the splenium of the corpus callosum on MRI existed prior to the onset of cognitive dysfunction, and expanded gradually. For early diagnosis of NIID, it is important to focus not only on the characteristic high signal intensity at the corticomedullary junction, but also on the signal at the splenium of the corpus callosum from the early stage.

A 33-year-old man with an unremarkable family history has had limb muscle weakness, joint contracture and skeleton deformation from early childhood. He was diagnosed with spinal muscular atrophy (SMA) by a pediatrician. He needed assistance and used orthoses in his daily life. There was no subjective sensory disturbance. However, physical examination showed slight sensory impairment, and nerve conduction study indicated sensory motor axonal neuropathy. This finding suggested Charcot-Marie-Tooth disease (CMT). Gene analysis detected MORC2 S87L mutation, leading to a diagnosis of CMT type 2Z. Patients with MORC2 S87L mutation are known to exhibit a severe phenotype, and may mimic SMA. It is important to demonstrate subclinical sensory neuropathy in patients with MORC2 S87L mutation mimicking SMA.

一般に，小型の板ばね部品の製造には，金型の製造とそれを用いた成形および熱処理の工程が必要である．しかしながら，その試作や小ロットの製造において金型の製造に時間とコストを要し，さらに熱処理における工程制御が難しいため，その場合には多くの手作業による工程が必要となっている．そこで著者らは，その試作や小ロットの製造における自動化を目指して，小出力半導体レーザを用いたレーザ焼入れフォーミングを提案する．本報では，その基礎現象を解明するためにレーザ照射時の薄鋼板の変形の様子をモニターする．さらに赤外線サーモグラフィにより，その温度分布も観察する．それらの結果より，面内方向の熱の蓄熱作用が，面外方向のフォーミングプロセスに影響することを解明した．, The die set and the heat treatment processes are needed to fabricate small size flat spring in general. However, a problem has been emerged that there are many traditional handmade processes because it takes long time to manufacture the die set, its cost is higher and the heat treatment control is difficult in prototype parts and small lot production. We therefore propose a hybrid laser hardening and forming method with a small power diode laser as an automatic controlled system to manufacture the small size plate spring for prototype and small lot production. In the present report, we attempt to monitor the deformation of thin steel plate during laser irradiation to investigate the basic phenomena. On the other hand, we observe the temperature distribution on the thin plate during laser irradiation with an infrared thermography. As a result, it can be seen that the thermal storage in-plane direction affects the laser forming process.

In recent years, the recycling of resources has become important because of the aggravation of global environmental concerns. In light of this, it is necessary to minimize the resource needs of current production systems. This concept is called sustainable development. When this concept is applied to machine tools, the assumption is that small parts should be processed using small machines. Additionally, the diversification of consumer needs and the ephemeralization of product life cycles are progressing in industry. As a result, the overall production system has changed from high-mix low-volume production manufacturing, to variant types in variable quantity. In this background, the cell production system is receiving attention as a production system that can achieve variant types in variable quantity. The cell production system also requires miniaturization and process consolidation of machine tools, which has given rise to the need to consolidate heat treatments, especially as part of the process consolidation of machine tools. Laser beams have proved to be effective heat sources when integrated into heat-treatment processes, such as quenching and tempering on machine tool tables. On the other hand, In the case of the thin plate, it is well known that the deformation of a plate occurs due to laser irradiation, as named a laser forming. The laser forming is also effective to generate the complex shape without a press die set. Thus, we propose that the hybrid process of laser heat treatment and forming of thin plate with a small power semiconductor laser, and demonstrate that the proposed method makes it feasible to generate the hardened sheet metal products with a compact machine tools. Moreover, considering the power consumption in laser quenching and forming process, we investigate an appropriate laser irradiation condition from a view of reducing the environmental burden.

Nowadays, resource saving technologies have become important because of increasing global environmental problems. Moreover, demand is increasing for the manufacturing and machining of small mechanical parts because of the downsizing of electronic mobile devices. Thus, one requirement has emerged that these small parts have to be fabricated by smaller machine tools to reduce the environmental burden. Here, when we look at the heat treatment process, it is found that most small parts are generally treated with a large size furnace as well. Therefore, we focus on compact machine tools to develop the clean and energy-saving technology in the manufacturing fields. In the present report, we consider an in-situ laser heat treatment technology integrated on the table used for compact machine tools. In particular, we perform the entire laser hardening of a small thin plate with a small power semiconductor laser, which is an attempt to harden a whole steel sheet. However, thin plates deform during the laser hardening process, which is called “laser forming.” Thus, we discuss an effective irradiation path to prevent the deformation of plates while quenching the entire plate. Moreover, considering the power consumption in the laser quenching process, we investigate an appropriate laser irradiation condition.

Demand is increasing for the manufacturing and machining of small mechanical parts. We focus on using a multi-functional desktop-sized machine tool to meet such demands because power consumption is decreased when they are machined. However, few reports have focused on heat treatment among manufacturing processes, we investigate the laser heat treatment of small parts as a highly efficient and eco-friendly method and propose in-situ heat treatment on a desktop-sized machine tool using a low-power diode laser beam. We quenched a small thin steel plate with a 30 W diode laser source. Our proposed method makes it feasible to quench a small thin steel plate and effectively reduces the power consumption of in-situ heat treatment by a desktop-sized machine tool.

We report on the fabrication and analysis of basic digital circuits containing InAs nanowire transistors on a host substrate. The nanowires were assembled at predefined positions by means of electric field-assisted self-assembly within each run generating numerous circuits simultaneously. Inverter circuits composed of two separated nanowire transistors forming a driver and an active load have been fabricated. The inverter circuits exhibit a gain (>1) in the MHz regime and a time constant of about 0.9 ns. A sample & hold core element is fabricated based on an InAs nanowire transistor connected to a hold capacitor, both on a Silicon and an InP isolating substrate, respectively. The low leakage read-out of the hold capacitor is done by InP-based metal-insulator heterojunction FET grown on the same substrate prior to nanowire FET fabrication. Experimental operation of the circuit is demonstrated at 100 MHz sampling frequency. The presented approach enables III/V high-speed, low-voltage logic circuits on a wide variety of host substrates which may be up scaled to high volume circuits. Copyright © 2012 The Institute of Electronics, Information and Communication Engineers.

We have proposed an auto-memoization processor based on computation reuse. The table for registering inputs/outputs is implemented by a ternary CAM, and the input sequences are stored onto the table, being folded into tree forms. This paper proposes a new registration model for merging multiple input entries into a single entry. The new model can efficiently store input values and can reduce the search cost. The result of the experiment with SPEC CPU95 suite benchmarks shows that the new model improves the maximum speedup ratio from 40.5% to 50.0%, and the average speedup ratio from 10.5% to 16.4%.

A novel low-power 8-bit successive approximation (SA) ADC using multiple-valued approach is presented. In contrast to conventional 1bit/step SA ADCs, 2bit/step conversion is employed, and combined with the split capacitor array and dual sampling technique to reduce the power consumption. Transistor level simulation, assuming 0.18-µm standard CMOS technology, shows that the total power consumption decreases by about 20% compared with that obtained for a 1bit/step counterpart at a sampling frequency of 100 kHz. Since the digital part consumes more power than the analog part, the present approach is expected to be more attractive for ADCs using advanced process technology.

We have investigated effects of impurity substitution of Fe for Co sites on magnetic and dielectric properties in CaBa(Co1-xFex)4O7 crystals in magnetic fields. The non-doped compound, CaBaCo4O7 with the polar space group Pbn21, shows a large change of electric polarization ΔP along the c axis below a ferrimagnetic transition temperature. With increasing x, the transition temperatures for the ferrimagnetic and ferroelectric-like phases are shifted towards lower and these phases are completely collapsed above x=1.56%. We have also investigated the magnetic field effects for CaBa(Co1-xFex)4O7 crystal with a doping level x=0.5% where the ferrimagnetic and ferroelectric-like phases sustain. Then a relatively large magnetocapacitance, Δɛ(H)/ɛ(0) [ɛ(H) – ɛ(0)]/ɛ(0), of 45% at 58K was observed, which is not significantly reduced from the parent compound.

Doctor of Philosophy in Engineering, Doshisha University

Doctor of Philosophy in History, Doshisha University