Simultaneous Measurement of Torsional Oscillator and NMR of Very Dilute 3He in Solid 4He

We have investigated the NMR properties of dilute 3He impurities in solid 4He contained in a torsional oscillator (TO) by the simultaneous measurement of the NMR and the torsional oscillator response of the so-called supersolid 4He. From measurements on samples with one hundred to a few hundred ppm of 3He, we have found three different states of 3He. The first is the homogeneously distributed isolated 3He atom in a solid matrix of 4He. The second is the 3He cluster in a homogeneous 4He matrix, which appears below the phase separation temperature of a solid mixture. The third is the 3He cluster in some nonuniform part of a 4He crystal. We find that 3He atoms contained in the third component remain in a nearby location even above the phase separation temperature. Based on the fact that even a ppm of 3He affects the supersolid response in a TO below and above the phase separation temperature, we propose that the nonuniform part of a crystal that holds the third type of 3He and thus has a higher local concentration of 3He plays an important role in the supersolid phenomenon in a TO.Comment: 5 pages, 5 figures, Accepted for publication in Physical Review

清酒老香の主成分 dimethyl trisulfide の生成を制御する因子に関する研究

内容の要約広島大学(Hiroshima University)博士(農学)Agriculturedoctora

Temporal and Spatial Cellular Distribution of Neural Crest Derivatives and Alpha Cells during Islet Development

Recent studies have revealed that signals from neural crest (NC) derivatives regulate the mass, proliferation, and maturation of beta cells in developing fetal pancreas. However, little is known about the cellular distribution of NC derivatives during pancreatic development or the process whereby the developing islets are enclosed. We studied the temporal and spatial distribution of NC derivatives and endocrine cells at each developmental stage. At embryonic day 10.5 (E10.5) of mouse embryo, NC derivatives that migrated to the prospective pancreatic region were distributed in close proximity to pancreatic epithelial cells. As development advanced, most NC derivatives progressively surrounded endocrine rather than exocrine cells, and were distributed in closer proximity to alpha cells rather than to beta cells. At E20, approximately 70% of the NC derivatives enclosing endocrine cells were distributed in close proximity to alpha cells. Moreover, the expression of SynCAM, a Ca2+-independent homophilic trans-cell adhesion molecule, was confirmed from E16.5 on and was more remarkable at the cell boundaries of alpha cells and NC derivatives. These findings suggest that NC derivatives might be distributed in close proximity to alpha cells as a result of homophilic binding of SynCAM expressed by alpha cells and NC derivatives during islet development

アクロレインβ-アニオン等価体およびジエノールシリルエーテル前駆体としてのγ-ヘテロ原子置換-α,β-エポキシシラン

第2回次世代を担う有機化学シンポジウム (2004年6月25-26日) 発表資

Development of Attitude Sensor using Deep Learning

A new method for attitude determination utilizing color earth images taken with COTS visible light camera is presented. The traditional earth camera has been used for coarse attitude determination by detecting the edge of the earth, and therefore it can only provide coarse and 2-axis information. In contrast, our method recognizes the ground pattern with an accuracy of sub-degrees and can provide 3-axis attitude information by comparing the detected ground pattern and the global map. Moreover, this method has advantages in the size, mass and cost of the detector system which consists of a cheap optical color camera and a single board computer. To demonstrate the method in space, we have developed a sensor system named “Deep Learning Attitude Sensor (DLAS)”. DLAS uses COTS camera modules and single board computers to reduce the cost. The obtained images are promptly analyzed with a newly developed real-time image recognition algorithms

Application of the 0-1 Programming Model for Cost-Effective Regression Test

Abstract-This paper reports an application of the 0-1 programming model to the regression testing plan for an industrial software. The key idea is to formulate a testing plan as a 0-1 programming problem (Knapsack problem). The empirical study shows that the 0-1 programming method can produce a cost-effective testing plan in which all potential regressions are found at only 22% of the cost of running all test cases

Impurity conduction in phosphorus-doped buried-channel silicon-on-insulator field-effect transistors

We investigate transport in phosphorus-doped buried-channel metal-oxide-semiconductor field-effect transistors at temperatures between 10 and 295 K. In a range of doping concentration between around 2.1 and 8.7 x 1017 cm-3, we find that a clear peak emerges in the conductance versus gate-voltage curves at low temperature. In addition, temperature dependence measurements reveal that the conductance obeys a variable-range-hopping law up to an unexpectedly high temperature of over 100 K. The symmetric dual-gate configuration of the silicon-on-insulator we use allows us to fully characterize the vertical-bias dependence of the conductance. Comparison to computer simulation of the phosphorus impurity band depth-profile reveals how the spatial variation of the impurity-band energy determines the hopping conduction in transistor structures. We conclude that the emergence of the conductance peak and the high-temperature variable-range hopping originate from the band bending and its change by the gate bias. Moreover, the peak structure is found to be strongly related to the density of states (DOS) of the phosphorus impurity band, suggesting the possibility of performing a novel spectroscopy for the DOS of phosphorus, the dopant of paramount importance in Si technology, through transport experiments.Comment: 9 figure