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31.
A 33-year-old man who had been treated for chronic prostatitis was diagnosed to have urachal cysts by transabdominal ultrasonography. Cystoscopy revealed protuberance at the dome of the bladder. Computerized tomography scan and magnetic resonance imaging showed the mass to be mostly cystic but partly solid. Resection of the urachal cysts and partial cystectomy were performed. Histopathologically, most cysts had a normal cylindrical epithelium with retention of mucinous substance. However, several small cysts contained epithelial cells resembling tubulo-villous adenoma and showing mitotic figures. This case was concluded as urachal carcinoma detected in its very early stage.  相似文献   
32.
Co-Al-O film was fabricated using the reactive r.f. magnetron sputtering technique. A maximum magnetoresistance (MR) of approximately 7% was established through optimizing the sputter deposition conditions such as sputter power and gas flow rate. TEM characterization of the film revealed a nano-granular structure that consisted of ferromagnetic grains with grain diameters on the order of several nm together with non-magnetic grain boundary layers with the thickness on the order of less than 1 nm. The large MR was attributed to electron tunneling thorough this very thin grain boundary layer between individual ferromagnetic grains.  相似文献   
33.
We describe a compact 1.5%-/spl Delta/ athermal silica-based 100-GHz-spacing 16-channel arrayed-waveguide grating (AWG) multi/demultiplexer with a modified groove design for a very low excess loss. We propose new approaches for modifying the shape of the grooves and the arrayed waveguides and optimize the shape modifications for 1.5%-/spl Delta/ waveguides. By employing this modified groove design, we greatly reduced the groove excess loss from 1.9 to 0.4 dB in the 1.5%-/spl Delta/ athermal AWG.  相似文献   
34.
35.
Ca3Co4O9 (p-type) and Zn0.98Al0.02O (n-type) pellets were prepared by conventional sintering (CS) and Spark Plasma sintering (SPS) starting from the oxides. The best p-type sample was SPS Ca3Co4O9 obtained from pre-sintered pellets, with electrical conductivity σ = 144 S/cm and Seebeck coefficient S = 172 μV/K at 800 °C, while thermal conductivity κ = 2.00 W/m×K and figure of merit ZT = 0.23. The best n-type sample was CS Zn0.98Al0.02O showing σ = 83 S/cm and S = ?268 μV/K at 800 °C, while = 5.03 W/m×K and ZT = 0.127. The output power of a module based on SPS Ca3Co4O9 and CS Zn0.98Al0.02O legs was 2.26 mW (with T = 500 °C, ΔT = 248 °C).  相似文献   
36.
37.
In this letter, we have developed a novel technique for improving the temperature stability of an athermal silica-based arrayed-waveguide grating with a resin-filled groove. We compensated for the residual second-order temperature dependence of the passband wavelength using the pressure-induced refractive index change in a resin inserted into the optical paths. Pressure control under the temperature variation was achieved by using a structure composed of an optical fiber piston and bimetal actuators. We demonstrated that the passband wavelength variation was successfully reduced from 0.080 to 0.025 nm in a -40degC - 85degC temperature range, without any insertion loss increase or spectral change.  相似文献   
38.
An 8-Gb multi-level NAND Flash memory with 4-level programmed cells has been developed successfully. The cost-effective small chip has been fabricated in 70-nm CMOS technology. To decrease the chip size, a one-sided pad arrangement with compacted core architecture and a block address expansion scheme without block redundancy replacement have been introduced. With these methods, the chip size has been reduced to 146 mm/sup 2/, which is 4.9% smaller than the conventional chip. In terms of performance, the program throughput reaches 6 MB/s at 4-KB page operation, which is significantly faster than previously reported and very competitive with binary Flash memories. This high performance has been achieved by the combination of the multi-level cell (MLC) programming with write caches and with the program voltage compensation technique for neighboring select transistors. The read throughput reaches 60 MB/s using 16I/O configuration.  相似文献   
39.
The mixture of 5'-guanylylimidodiphosphate (Gpp(NH)p)/EDTA/NaCl has been used to delineate low-affinity conditions for agonists binding to G-protein-linked receptors. The effects of this mixture on [3H]RX821002 (2-methoxyidazoxan) binding to alpha2-adrenoceptors were evaluated in different tissues. The density of alpha2-adrenoceptors in the presence of the mixture was 11, 78 and 60% higher in human cortex (predominant alpha2A), human caudate (alpha2A + alpha2C) and rat kidney (alpha2A + alpha2B), respectively, than in its absence. In rat kidney, masking of alpha2B-adrenoceptors by ARC239 (2-[2-[4-(o-methoxyphenyl)-piperazin-1-yl]-ethyl]-4,4-dimethyl-1,3 -(2H,4H)-isoquinolindione) (50 nM) or masking of alpha2A-adrenoceptors by BRL44408 (2-[2H-(1-methyl-1,3-dihydroisoindole)methyl]-4,5-dihydroimidaz ole) (100 nM) demonstrated that the increase was in the alpha2B-adrenoceptor but not in the alpha2A-adrenoceptor subtype.  相似文献   
40.
This paper describes a heterogeneous multi-core processor (HMCP) architecture that integrates general-purpose processors (CPUs) and accelerators (ACCs) to achieve exceptional performance as well as low-power consumption for the SoCs of embedded systems. The memory architectures of CPUs and ACCs were unified to improve programming and compiling efficiency. Advanced audio codec-low complexity (AAC-LC) stereo audio encoding was parallelized on a heterogeneous multi-core having homogeneous processor cores and dynamically reconfigurable processor (DRP) ACC cores in a preliminary evaluation of the HMCP architecture. The performance evaluation revealed that 54times AAC encoding was achieved on the chip with two CPUs at 600 MHz and two DRPs at 300 MHz, which achieved encoding of an entire CD within 1- 2 min.  相似文献   
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