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The National Institute of Information and Communications Technology (NICT) has developed a Sr optical lattice clock and optical ion clocks employing In+and Ca+. The centimeter-level uncertainty of site elevation is the cause of 10^(-18)-level frequency uncertainties of optical frequency standards. It is significantly important to understand frequency changes caused by solid-earth tides that often range from 10 to 20 cm in amplitude, by oceanic tidal loading, crustal deformations due to earthquakes, and ground movements with groundwater changes for the stable operation of optical atomic clocks.NICT and partners including the Geospatial Information Authority of Japan (GSI) have been jointly conducting leveling surveys and relative gravimeter observations at NICT’s headquarters in Koganei. These observations reduce the contribution of gravitational redshift to the total uncertainty of the optical lattice clock to the 10^(-19)level. With the support of National Institute of Polar Research (NIPR), absolute gravity measurements were performed in August 2019 and May 2022 to evaluate the effects of the 2011 off the Pacific coast of Tohoku Earthquake on postseismic crustal movement. The obtained absolute gravity change between the two periods was -43.8 μGal, which matches the trend of GNSS vertical movement obtained by GSI. We have introduced a Micro-g LaCoste’s gPhoneX gravimeter for continuous gravity measurements nearby the optical clocks in the end of 2021 and have started to investigate the temporal variation of the ground water level in Koganei. We will present preliminary results of these geodetic measurements., The 28th IUGG General Assembly (IUGG2023) (Berlin 2023)

Experiments reported here were conducted using atmospheric nitrogen gas remote plasma with a pulsed power source. Thesterilization efficiency, major sterilization factors and most appropriate sterilization conditions were determined. By varyingseveral factors such as hotplate temperature, relative humidity, water vapor supply location, etc., the most appropriatesterilization conditions were identified. The temperature of the hotplate was varied from 55°C to 75°C and with this 20°Cincrease in temperature, sterilization was completed in half the time. In this experiment, it was confirmed that the combinedeffect of a relative humidity (RH) of 0.5% and nitrogen gas was superior to the use of nitrogen gas alone. Furthermore,it was clarified that the optimal humidity was in the range of 0-5 % RH. When RHs of 0, 0.5 and 5% were tested, 0.5%RH was found to be optimal for sterilization. The location of the water vapor supply was changed relative to the hotplate,and use of the most remote port upstream of the reactor resulted in the most efficient sterilization. In addition, the resultscorrelated with the amount of NO radicals generated. The NO radical is the precursor of OONO • - (peroxynitrite anion radical). The sterilization factors associated with this experiment were NO radicals, H2O2, OH radicals, O2• - (superoxideanion radicals) and OONO • -. Only OONO • - production correlated with sterilization efficiency. Therefore, OONO • - isthought to be the major factor for nitrogen gas plasma sterilization. In addition, as already described, the highest sterilizationefficiency was with 0.5% RH and the amount of OONO • - produced correlated with the RH. These data support theidea that OONO • - is the major contributing factor for nitrogen gas plasma sterilization. The D values for this experimentwere approximately 10 min.

The relationship between abnormal cell proliferation and aberrant control of hormonal secretion is a fundamental and poorly understood issue in endocrine cell neoplasia. Transgenic mice with parathyroid-targeted overexpression of the cyclin D1 oncogene, modeling a gene rearrangement found in human tumors, were created to determine whether a primary defect in this cell-cycle regulator can cause an abnormal relationship between serum calcium and parathyroid hormone response, as is typical of human primary hyperparathyroidism. We also sought to develop an animal model of hyperparathyroidism and to examine directly cyclin D1’s role in parathyroid tumorigenesis. Parathyroid hormone gene regulatory region–cyclin D1 (PTH–cyclin D1) mice not only developed abnormal parathyroid cell proliferation, but also developed chronic biochemical hyperparathyroidism with characteristic abnormalities in bone and, notably, a shift in the relationship between serum calcium and PTH. Thus, this animal model of human primary hyperparathyroidism provides direct experimental evidence that overexpression of the cyclin D1 oncogene can drive excessive parathyroid cell proliferation and that this proliferative defect need not occur solely as a downstream consequence of a defect in parathyroid hormone secretory control by serum calcium, as had been hypothesized. Instead, primary deregulation of cell-growth pathways can cause both the hypercellularity and abnormal control of hormonal secretion that are almost inevitably linked together in this common disorder.