Analysis of the proteinaceous components of the organic matrix of calcitic sclerites from the soft coral Sinularia sp.

An organic matrix consisting of a protein-polysaccharide complex is generally accepted as an important medium for the calcification process. While the role this "calcified organic matrix" plays in the calcification process has long been appreciated, the complex mixture of proteins that is induced and assembled during the mineral phase of calcification remains uncharacterized in many organisms. Thus, we investigated organic matrices from the calcitic sclerites of a soft coral, Sinularia sp., and used a proteomic approach to identify the functional matrix proteins that might be involved in the biocalcification process. We purified eight organic matrix proteins and performed in-gel digestion using trypsin. The tryptic peptides were separated by nano-liquid chromatography (nano-LC) and analyzed by tandem mass spectrometry (MS/MS) using a matrix-assisted laser desorption/ionization (MALDI) - time-of-flight-time-of-flight (TOF-TOF) mass spectrometer. Periodic acid Schiff staining of an SDS-PAGE gel indicated that four proteins were glycosylated. We identified several proteins, including a form of actin, from which we identified a total of 183 potential peptides. Our findings suggest that many of those peptides may contribute to biocalcification in soft corals

Development of vibration mechanical stimuli loading device for live cell fluorescence microscopy

Bone metabolism is regulated by mechanical stimuli such as gravity and exercise. If bone formation can be promoted by artificial mechanical stimulation, the quality of life of the aging society can be improved, such as by reducing the progression of osteoporosis and preventing patients from being bedridden. Micro-vibration stimulation with frequencies of 15 Hz to 90 Hz and acceleration amplitudes of 0.1 g to 0.3 g is effectively promotes bone formation in animal models. However, the mechanism of how these weak vibrations are sensed by bone cells and are used to regulate bone metabolism is unknown. In this study, we developed a device to apply micro-vibration stimuli to osteoblasts cultured on a glass bottom dish and observed the cell response to the stimuli using a confocal laser scanning fluorescence microscope. The device performance was confirmed using driving tests, and the calcium signaling response of osteoblasts to micro-vibration stimuli was observed in real time and in situ. The calcium signaling response characteristics of the cells differed when the cells were subjected to 45 Hz and 90 Hz micro-vibration stimuli, even under a constant acceleration amplitude of 0.2 g

A cylindrical micro ultrasonic motor using micro-machined piezoelectric vibrator

A micro ultrasonic motor using a micro-machined cylindrical bulk piezoelectric vibrator is introduced. This motor consists of the vibrator, a glass case and a rotor. The diameter of the piezoelectric vibrator is 0.8 mm and that of the motor case is 1.8 mm. Since the stator transducer is fixed at the end of the cylinder, it is easy to support the vibrator and the structure of the motor is not complicated. In addition, the vibrator and rotor are supported by the glass case. This is important for the micro ultrasonic motor because it is difficult to support the vibrator when the vibrator is miniaturized. We have fabricated and evaluated the cylindrical shaped traveling type micro ultrasonic motor using this vibrator.</p

Switching waveform design with gate charge control for power MOSFETs

The switching waveform design, especially controlling and optimizing the slew rate, is an efficient technique to mitigate the trade-off between decreasing the loss and increasing the noise of the switching power device. The digital active gate driver which generates the gate waveform to achieve the designed switching waveform requires a significant computational burden because the optimum driving point is searched automatically and comprehensively. This paper proposes a novel and simple method to calculate gate waveforms to achieve the designed switching waveforms. This method calculates how much gate charge is additionally required to match the designed waveform by exploiting the voltage and current response of the power device to the small gate charge pulse. The validation of this method is demonstrated by simulation in the case of both the drain-source voltage design and the drain current design. The deviation from the designed waveform is quantified in this paper

Indoleamine 2,3-dioxygenase and trophoblast invasion in caesarean scar pregnancy: Implications for the aetiopathogenesis of placenta accreta spectrum

Immunohistochemical localisation of indoleamine 2,3-dioxygenase was studied in order to better understand the pathophysiology of placenta accreta spectrum. In the decidua staining for indoleamine 2,3-dioxygenase was found in the glandular epithelium with some additional positive cells. Extravillous cytotrophoblast invasion was present in the myometrium which was not covered by the decidual tissue whereas myometrial invasion of cytotrophoblasts was absent where this tissue lay deep to decidua. These results suggest that indoleamine 2,3-dioxygenase expression in the decidua may normally control trophoblast invasion and absence of its expression where decidua is absent may be involved in the pathogenesis of the over-invaded placenta.We are grateful to the Grant-in-Aid for Scientific Research (17K11238), Japan Society for the Promotion of Science for financial support

Speed-Up Gate Pulse Method to Suppress Switching Loss and Surge Voltage for MOS Gate Power Devices

There is a trade-off between surge voltage and switching loss in power semiconductors, and it has been difficult to reduce both. In order to solve this problem, the digital gate drive method has been studied. However, the digital gate drive method has the problem that the gate drive circuit is complicated and it takes time to search for the optimal drive waveform. In this study, we have proposed a new method that does not require optimization search, but only adds a simple circuit, which is expected to have the same effect as the digital gate drive method.IEEE International Symposium on Power Semiconductor Devices and ICs (ISPSD 2022), 22-25 May 2022, Vancouver, Canad