STARVATION TOLERANCE OF EARLY STAGE LAGUNCULA PULCHELLA (NATICIDAE)

The starvation tolerance of the moonsnail Laguncula pulchella was examined under nonfeeding conditions in the laboratory using individuals at the early stages of development, which comprised subadults (≤19 mm shell width) and newly hatched juveniles (≤1.7 mm). The newly hatched juveniles survived for ≤86 days at 20°C, ≤56 days at 25°C, and ≤22 days at 30°C, whereas subadults survived for ≤323 days at 20°C and ≤181 days at 30°C. These starvation tolerance ranges were relatively greater than those of other gastropods. There was a positive correlation between shell size and the duration of juvenile survival, indicating that the juveniles hatched at larger sizes have more energy stores. The high starvation tolerance of L. pulchella might be contributing to its invasion success in habitats with low prey availability.This study was partly supported by JSPS KAKENHI Grant (20H03062)

Quantum Clocks and Gravitational Time Dilation and the Quantum Interference

Recently, a proper time observable for a quantum clock is introduced and it is found that the proper time read by one clock conditioned on another clock reading a different proper time obeys classical time dilation in accordance with special relativistic kinematical time dilation. Here, we extend this proposal to a weak gravitational field in order to investigate whether the weak equivalence principle holds for quantum matter. We find that for general quantum states the quantum time dilation in a weak gravitational field obeys a similar gravitational time dilation found in classical relativity. However, unlike the special relativistic case, the time dilation involves the external time (a background coordinate time at the observer on the earth) as well as the proper times of two clocks. We also investigate a quantum time dilation effect induced by a clock in a superposition of wave packets localized in momentum space or in position space and propose the setup to observe the gravitational effect in the quantum interference effect in the time dilation.Comment: 11 pages, 2 figure

Note on the Time Dilation for Charged Quantum Clocks

We derive the time dilation formula for charged quantum clocks in electromagnetic fields. As a concrete example of non-inertial motion, we consider a cyclotron motion in a uniform magnetic field. Applying the time dilation formula to coherent state of the charged quantum clock, we evaluate the time dilation quantum-mechanically.Comment: 10 pages, 2 figure

Attenuation performance of geosynthetic sorption sheets against arsenic subjected to compressive stresses

The attenuation layer method has been considered an effective countermeasure to deal with excavated soils and rocks containing geogenic toxic elements like arsenic (As). The geosynthetic sorption sheet is a geosynthetic product that can be employed in the attenuation layer method applications as a sorption material. The sorption sheets used in the attenuation layer will be inevitably subjected to overburdened loads in the field. In this study, laboratory column experiments are conducted to evaluate the attenuation performance of the geosynthetic sorption sheets coated with hydrotalcite as sorbent against As under different overburden pressure conditions (10, 100, and 200 kPa). Experimental results showed that the cumulative sorption masses of As for 200 kPa cases are approximately 10.5–13.3 times greater than that for 10 kPa cases. Microstructure characterizations of the geosynthetic sorption sheet before and after loading were also detected. More compacted and involved fiber configuration as a result of higher loading produces a more effective contact between As solution and hydrotalcite. The presence of partial dissolution of hydrotalcite is confirmed through the chemical analysis of effluent. However, hydrotalcite would gradually become stable during continuous use

Stochastic Inverse Identification of Nonlinear Roll Damping Moment of a Ship Moving at Nonzero-Forward Speeds

The nonlinear responses of ship rolling motion characterized by a roll damping moment are of great interest to naval architects and ocean engineers. Modeling and identification of the nonlinear damping moment are essential to incorporate the inherent nonlinearity in design, analysis, and control of a ship. A stochastic nonparametric approach for identification of nonlinear damping in the general mechanical system has been presented in the literature (Han and Kinoshits 2012). The method has been also applied to identification of the nonlinear damping moment of a ship at zero-forward speed (Han and Kinoshits 2013). In the presence of forward speed, however, the characteristic of roll damping moment of a ship is significantly changed due to the lift effect. In this paper, the stochastic inverse method is applied to identification of the nonlinear damping moment of a ship moving at nonzero-forward speed. The workability and validity of the method are verified with laboratory tests under controlled conditions. In experimental trials, two different types of ship rolling motion are considered: time-dependent transient motion and frequency-dependent periodic motion. It is shown that this method enables the inherent nonlinearity in damping moment to be estimated, including its reliability analysis

アポトーシス促進因子Bidの制御機構

金沢大学がん進展制御研究所昨年度単離したBid結合因子(clone-2)の機能解析を進めた。1,clone-2遺伝子の発現分布をNorthern Blotで解析した。正常組織(CLONTECH社のMultiple Tissue Northern Blotを利用した)ではBrain、Liverで強いmRNAの発現を検出した。培養細胞(Cos7,Hela, HEK293,HepG2,Jurkat K562,THP1)ではHepG2細胞でやや強く、Cos7,HEK293で弱いmRNA発現を検出した。RT-PCR解析では全てのcell lineで発現が確認された。2,clone-2の安定発現細胞株の樹立を試みた。Jurkat細胞にのcDNAを組み込んだpIRES2-EGFP(CLONTECH社)ベクターを導入し、G418耐性、GFP発現を指標にclone-2の安定発現クローンを4種類得た。4クローン中2クローンがレコンビナントFasリガンドで誘導されるアポトーシスに耐性を示した。3,clone-2の細胞内局在を調べた。clone-2に対するポリクローナル抗体を作製し、HepG2細胞を免疫染色したところ、ミトコンドリアに強い染色像が見られた。HepG2細胞を分画し、western blot解析したところ、ミトコンドリアを含むheavy membrane画分にclone-2のカルボキシ末端側とみられる14kDaのバンドを検出した。clone-2の全長に相当する蛋白のバンドは確認できなかった。4,アンチセンスRNA発現ベクター導入による内在性clone-2の発現阻害を試みたが、14kDaのバンドの消失は認められなかった。以上の結果より、過剰発現系においてはclone-2がBidで誘導されるアポトーシスに対して抑制的に働く可能性が示唆された。研究課題/領域番号:13770106, 研究期間(年度):2001-2002出典：「アポトーシス促進因子Bidの制御機構」研究成果報告書　課題番号13770106（KAKEN：科学研究費助成事業データベース（国立情報学研究所）） （ https://kaken.nii.ac.jp/ja/grant/KAKENHI-PROJECT-13770106/ ）を加工して作