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2.
It has been previously reported that Bryostatin 1 (Bryo1) induces differentiation of the human acute lymphoblastic leukemia (ALL) cell line, Reh, to a monocytoid B-cell stage. In this study we demonstrate that a novel protein, ubiquitin COOH-terminal hydrolase (UCH-L1), is associated with this differentiation. Reh cells were treated with 200 nmol/l of Bryo1 for 72 h and analyzed for changes in morphology, surface immunophenotype, acid phosphatase and terminal deoxynucleotidyl transferase. Protein patterns of the parent and differentiated cells, by two-dimensional polyacrylamide gel electrophoresis (2D PAGE), were studied. Bryo1-treated cells expressed morphologic, phenotypic and enzymatic features of the monocytoid B-cell stage. The UCH-L1 enzyme (MW-pl 34-5.3) was detected by 2 D PAGE in the differentiated, but not in parent cells. The presence of UCH-L1 in the Bryo1-treated cells was further confirmed by immunoblotting of 2 D PAGE using UCH-L1 polyclonal antibody. Ubiquitin expression was studied in parent and Bryo1-treated cells and was compared with 12-O-tetradecanoylphorbol-13-acetate (TPA)-treated cells. Both agents, TPA and Bryo1, increased the level of ubiquitin expression as detected by flow cytometry. Sodium borohydride, an inhibitor of UCH-L1, inhibited the Bryo1-induced differentiating effect on Reh cells. To date, the mechanism by which Bryo1, exerts its B-cell differentiating effect is not fully understood. This study shows that UCH-L1 expression may play a major role in Bryo1-induced differentiation in pre-B-ALL. 相似文献
3.
The redistribution of impurity in alite during recrystallization has been confirmed by means of the electron probe microanalysis. Each of the main impurity components shows a significant decrease in content during recrystallization. This demonstrates that the growth velocity of alite exerts influence on the amount of the impurity taken up in alite in solid solution from the interstitial melt. Whether M3 or M1 occurs at ambient temperature depends on the cooling rate of clinker as well as the chemical composition of alite. 相似文献
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5.
Fusaomi Nagata Takanori Mizobuchi Shintaro Tani Tetsuo Hase Zenku Haga Keigo Watanabe Maki K. Habib 《Artificial Life and Robotics》2010,15(1):106-110
In this article, a new desktop orthogonal-type robot, which has the capacity of stick-slip motion control based on cutter
location data, is presented for lapping small metallic molds with a curved surface. The robot consists of three single-axis
devices with a high position resolution of 1 μm. A thin wooden stick tool with a ball-end shape is attached to the tip of
the z-axis. In order to improve the lapping performance, a novel stick-slip motion control method is developed in the control system.
The small stick-slip motion is orthogonally generated in the direction of the tool’s movement. The effectiveness of stick-slip
motion control is examined through an actual lapping test of an LED lens cavity. 相似文献
6.
Zeming Lu Fusaomi Nagata Keigo Watanabe Maki K. Habib 《Artificial Life and Robotics》2017,22(3):374-379
With the progress of electronics technology, the development of civilian UAV (unmanned aerial vehicle) applications becomes possible. In addition, smartphones have rapidly gained popularity and become very important due to the simple operability and mobility. Hence, there is a need to have an easy and flexible way to control a UAV using such technology. In this study, a remote controller using an iOS device is developed for a quadrotor to enable remote control with easy operations. Four basic programs for obtaining compass information, controlling a gimbal, autopilot function for return, and video preview function are developed and implemented for an iOS device. The basic functionalities of the programs are evaluated and confirmed through experiments using a quadrotor and an iOS device. 相似文献
7.
The stability region of the helical textures in3He-A in thev
s-H phase diagram is theoretically determined. Herev
sis the superflow velocity andH (v
s) is the external magnetic field. The pitch of the helixk
–1 that minimizes the Gibbs free energy and the corresponding inclination angles ofl andd are determined numerically as functions ofv
sandH. The NMR frequencies (two longitudinal and four transverse frequencies) associated with the helical texture are obtained.Work supported by the National Science Foundation under Grant No. DMR 76-21032. 相似文献
8.
Che-Chung Chou Evenson K.M. Zink K.R. Maki A.G. Jow-Tsong Shy 《Quantum Electronics, IEEE Journal of》1995,31(2):343-345
Nineteen new laser lines in the 11-μm wavelength region have been observed in CW oscillation from a CO2 laser with a high-Q, high-resolution cavity at a higher than usual current density. The frequency of each line has been measured using heterodyne frequency measurement techniques. Analysis of the frequencies shows that 15 lines are rotation-vibration transitions of the 0112-[1111,0311]I band (the first sequence hot band) of the CO2 molecule and four lines belong to the rotation-vibration transitions of the 0221-[12 20, 0420]I band of CO2 相似文献
9.
The application of vanadium-based membranes as the hydrogen separation membrane for a catalytic membrane reactor system was investigated for the direct production of hydrogen from methane. The methane conversion and hydrogen production rates of the catalytic membrane reactor system with Pd-coated 100 μm-thick vanadium-based membranes were comparable with the reactor using 50 μm-thick Pd–Ag alloy membrane at all temperatures examined. The methane conversion rates of the catalytic membrane reactor with the Pd-coated vanadium-based membranes were approximately 35% and 62% at 623 K and 773 K, respectively. The hydrogen production rates were around 660 μmol min−1 at 623 K, and reached over 1710 μmol min−1 at 773 K. The relationship between the methane conversion rates and hydrogen permeation fluxes of the catalytic membrane reactor confirmed that the removal of hydrogen from the reaction site enhances the methane decomposition reaction. Further, the vanadium based membrane exhibited good stability against Fe in a hydrogen containing atmosphere. 相似文献
10.
Gregory K Miller David A Petti Dominic J Varacalle Jr. John T Maki 《Journal of Nuclear Materials》2003,317(1):69-82
The fundamental design for a gas-cooled reactor relies on the behavior of the coated particle fuel. The coating layers, termed the TRISO coating, act as a mini-pressure vessel that retains fission products. Results of US irradiation experiments show that many more fuel particles have failed than can be attributed to one-dimensional pressure vessel failures alone. Post-irradiation examinations indicate that multi-dimensional effects, such as the presence of irradiation-induced shrinkage cracks in the inner pyrolytic carbon layer, contribute to these failures. To address these effects, the methods of prior one-dimensional models are expanded to capture the stress intensification associated with multi-dimensional behavior. An approximation of the stress levels enables the treatment of statistical variations in numerous design parameters and Monte Carlo sampling over a large number of particles. The approach is shown to make reasonable predictions when used to calculate failure probabilities for irradiation experiments of the New Production - Modular High Temperature Gas Cooled Reactor Program. 相似文献