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101.
T Shimamoto S Nakamura J Bollekens FH Ruddle K Takeshita 《Canadian Metallurgical Quarterly》1997,94(7):3245-3249
The DLX gene family is a family of divergent homeobox genes which are related to the Drosophila distal-less (Dll) gene and has been reported to be expressed primarily in the forebrain and craniofacial structures. We have previously identified a new member of this family, DLX-7. We now report that this gene is expressed in normal hematopoietic cells and leukemia cell lines with erythroid characteristics. We used an antisense oligonucleotide targeted against the translation start site of DLX-7 mRNA to inhibit its expression in a human erythroleukemia cell line K562, which expresses DLX-7 at a high level. The antisense oligonucleotide efficiently reduced the DLX-7 mRNA, while control oligonucleotides, including a mutant oligonucleotide identical to the antisense sequence except for four nucleotide mismatches, had no effect on DLX-7 mRNA level. Inhibition of DLX-7 expression decreased the plating efficiency by approximately 70% compared with control. The antisense treatment caused apoptosis, as shown by the terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-digoxigenin nick end labeling (TUNEL) method. Down-regulation of DLX-7 expression by antisense treatment was associated with a reduction in GATA-1 and c-myc mRNA levels. Thus, we conclude that DLX-7 is expressed in hematopoietic cells and that the inhibition of its expression results in the decreased levels of GATA-1 and c-myc genes, with an accompanying induction of apoptosis. 相似文献
102.
R 22-DEGDME is chosen as the prime working fluid pair for residential gas-fired absorption heat pumps.The vapour pressures and the heat capacities of mixtures are measured for various concentrations and temperatures and are correlated by a Rankine equation and a polynomial, respectively. The heats of mixing are measured at 10°C, and are correlated by a Redlich-Kister type polynomial.Based on these data, the pressure-temperature-concentration diagram and the enthalpy-concentration diagram are drawn, which make analysis of the absorption cycles possible. 相似文献
103.
A prototype absorption heat pump system whose rated capacities are 4000 kcal h−1 for cooling and 8000 kcal h−1 for heating was designed, constructed and tested. A mathematical model of this system was developed which demonstrates the superiority of DEGDME over TEGDME as solvent. The coefficients of performance of the constructed prototype are 0.55 for cooling and 1.25 for heating. 相似文献
104.
This paper presents a position sensorless drive of salient‐pole PM synchronous motors in all speed ranges including zero speed. Two position and speed estimation algorithms using the current differences between the actual and the estimated currents are proposed. One is based on the back emf estimation in the medium‐ and high‐speed ranges. Another is based on the position dependency of the winding inductances in the low‐speed ranges including zero speed. The effectiveness of the proposed algorithm has been verified with a six‐pole, 1.5‐kW, 1500‐rpm test motor. Stable sensorless speed control from zero to 3000 rpm within ±100% load torque range was achieved. © 2001 Scripta Technica, Electr Eng Jpn, 135(3): 64–73, 2001 相似文献
105.
Katsuko T. Nakahira Yoshiki Mikami Hiroyuki Namba Minehiro Takeshita Shigeaki Kodama 《Artificial Life and Robotics》2011,16(3):311-314
Along with protocols, domain names are critical internet resources. To build a safe, secure, and globally ubiquitous internet,
all entities responsible for the governance of domains must allocate their lower-level domains with competence and discipline
following the basic principle of decentralized governance. The governance and operation of a country code top-level domain
is delegated to the governing and operating entity of the relevant country or territory. There are great differences among
these entities in domain allocation policy, fees, discipline, and technical competence. The undertaking of governing a global
infrastructure requiring high integrity, such as the internet, on the basic principle of decentralized governance is unprecedented.
To enable this governance to work well, it is necessary to set up proper objectives for the governance of country domains,
and to use highly transparent criteria for a multi-faceted evaluation of how far these objectives have been achieved. This
article presents a set of country domain governance indicators which is intended to be used for the construction of a safe
and secure ubiquitous global network. 相似文献
106.
Shimizu M. Horiguchi M. Yamada M. Okayasu M. Takeshita T. Nishi I. Vehara S. Noda J. Sugita E. 《Electronics letters》1990,26(8):498-500
A small fibre amplifier module pumped by a 0.98 mu m LD has been fabricated. Using a low erbium content fibre with a 4.9 dB/mW gain coefficient, the module attained 33 dB gain at 1.535 mu m with only 80 mA drive current.<> 相似文献
107.
Youjian Liu Fitz M.P. Takeshita O.Y. 《IEEE transactions on information theory / Professional Technical Group on Information Theory》2002,48(12):3062-3079
Space-time coding has been studied extensively as a powerful error correction coding for systems with multiple transmit antennas. An important design goal is to maximize the level of space diversity that a code can achieve. Toward this goal, the only systematic algebraic coding theory so far is binary rank theory by Hammons and El Gamal (see ibid. vol. 46, p.524-42, 2000) for binary phase-shift keying (BPSK) modulated codes defined over binary field and quaternary phase-shift keying (QPSK) modulated codes defined over modulo four finite ring. To design codes with higher bandwidth efficiency, we develop an algebraic rank theory to ensure full space diversity for 2/sup 2k/ quadrature and amplitude modulated (QAM) codes for any positive integer k. The theory provides the most general sufficient condition of full space diversity so far. It includes the BPSK binary rank theory as a special case. Since the condition is over the same domain that a code is defined, the full space diversity code design is greatly simplified. The usefulness of the theory is illustrated in examples, such as analyses of existing codes, constructions of new space-time codes with better performance, including the full diversity space-time turbo codes. 相似文献
108.
High-power operation in 0.98-μm strained-layer InGaAs-GaAssingle-quantum-well ridge waveguide lasers
High power strained-layer InGaAs-GaAs graded-index separate confinement heterostructure (GRIN-SCH) single-quantum-well (SQW) lasers at an emission wavelength of 0.98 μm have been fabricated. A light power as high as 270 mW and a maximum front power conversion efficiency of 51.5% have been obtained for the antireflective and highly-reflective coated laser with 9-μm-wide ridge and 600-μm-long cavity 相似文献
109.
Takeshita O.Y. 《IEEE transactions on information theory / Professional Technical Group on Information Theory》2007,53(6):2116-2132
An interleaver is a critical component for the channel coding performance of turbo codes. Algebraic constructions are important because they admit analytical designs and simple, practical hardware implementation. The spread factor of an interleaver is a common measure for turbo coding applications. Maximum-spread interleavers are interleavers whose spread factors achieve the upper bound. An infinite sequence of quadratic PPs over integer rings that generate maximum-spread interleavers is presented. New properties of PP interleavers are investigated from an algebraic-geometric perspective resulting in a new non- linearity metric for interleavers. A new interleaver metric that is a function of both the nonlinearity metric and the spread factor is proposed. It is numerically demonstrated that the spread factor has a diminishing importance with the block length. A table of good interleavers for a variety of interleaver lengths according to the new metric is listed. Extensive computer simulation results with impressive frame error rates confirm the efficacy of the new metric. Further, when tail-biting constituent codes are used, the resulting turbo codes are quasi-cyclic. 相似文献
110.