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1.
In order to estimate the discharge performance of tall lead/acid cells (with tubular positives), changes in current and potential distributions with discharge progress were calculated with a computer on the basis of plate resistance and the current—potential—time relationship between small facing parts of positive and negative plates. The taller the cell, the larger the voltage drop along the plates. Thus, the discharge time became shorter despite a large amount of available active mass remaining in the bottom part of the plates.Various current-collector designs were evaluated, e.g., one with varying resistance at each height; a side conductor placed along the plates and connected to them at the top, centre and bottom, etc. Results revealed an optimum collector design with which the maximum discharge capacity could be obtained. Furthermore, it was shown that the side conductor markedly improved the discharge performance because the active mass near the connecting parts was appreciably used.  相似文献   
2.
SLC25A39/40, involved in mitochondrial GSH (mGSH) import from the cytoplasm, is essential for protection against oxidative stress and mitochondrial dysfunction. We examined the effects of cholestasis, through bile duct ligation (BDL) and lipopolysaccharide (LPS)-induced inflammation in mice, on Slc25a39/40 expression. Additionally, we used human clear cell renal carcinoma (KMRC-1) cells to elucidate the mechanism of regulation of SLC25A39/40 expression in the kidneys after LPS treatment. BDL resulted in a decrease in Slc25a39 mRNA in the liver and a decrease in Slc25a39/40 mRNA and protein in the kidneys. Consequently, there was a significant decrease in mGSH levels in the kidneys of BDL mice compared with those in sham mice. LPS treatment resulted in increased Slc25a40 expression in the kidneys. In KMRC-1 cells, the combination treatment of LPS-RS or FPS-ZM1 with LPS suppressed the LPS-induced increase in SLC25A40, suggesting that SLC25A40 expression could be regulated by the signaling pathway via toll-like receptor 4 and the receptor for advanced glycation end products, respectively. Our findings contribute to understanding the role of mGSH in the maintenance of the mitochondrial redox state. To the best of our knowledge, this is the first study that demonstrates the changes in Slc25a39/40 expression in mice with cholestasis-associated renal injury and LPS-induced inflammation.  相似文献   
3.
Time-decay stress-induced leakage current (SILC) has been systematically investigated for the cases of both Fowler-Nordheim (FN) stress and substrate hot-hole stress. From the three viewpoints of the reproducibility of the current component for the gate voltage scan, the change of oxide charge during the gate voltage scan, and the resistance of the current component to thermal annealing, it has been found that time-decay stress-induced leakage current is composed of five current components, regardless of stress type. Trap models corresponding to each current component have been proposed. In addition, it has also been proven that holes generate the electron traps related to one of those current components  相似文献   
4.
A widely tunable laser, consisting of a 100 GHz FSR triple-ring resonator and a semiconductor optical amplifier, is presented. The 100 GHz FSR ring resonator makes it possible to demonstrate 96 nm wavelength tuning with stable single-mode operation produced by a large threshold gain difference  相似文献   
5.
A 7-Mb BiCMOS ECL (emitter coupled logic) SRAM was fabricated in a 0.8 μm BiCMOS process. An improved buffer with a high-level output of nearly VCC is adopted to eliminate the DC current in the level converter circuit, and the PMOS transistor has a wide operating margin in the level converter. The configurable bit organization is realized by using a sense-amplifier switch circuit with no access degradation. A wired-OR demultiplexer for the ×1 output, having the same critical path as the ×4 output circuit, allows for the same access time between the two modes. The ×1 or ×4 mode is electrically selected by the external signal. A simplified programming redundancy technology, shift redundancy, is utilized. Address programming is performed by cutting only one fuse in the shift redundancy. The RAM operates at the ECL-10K level with an access time of 7 ns. and the power dissipation at 50 MHz is 600 mW for the × mode  相似文献   
6.
A high speed optical position-sensitive device (PSD) which was fabricated using a certain structure of the mesh-type resistive layer for reducing the junction capacitance is discussed. Its performance is compared with the conventional type of PSD (CPSD) fabricated by the same technology. The mesh-type high speed PSD (MEPSD) is based on an ion-implanted Si p-i-n structure and has an area of 14×14 mm2 with 30-μm strip-width and 125-μm pitch. The temporal response of the MEPSD is found to be improved by a factor of 1.83 times compared to the CPSD. A photosensitivity comparable to that of the CPSD is obtained. Its position linearity for detection is also comparable with that of the CPSD. The performance of the laboratory demonstration devices illustrates the feasibility of the concept for high-speed PSD  相似文献   
7.
The mobile multi-media applications require to lower the operating voltage of embedded SRAMs. The ECC circuit implementation for increasing soft-error and the access timing control that tracks access delay fluctuation in memory core should be considered for the low-voltage operation. A hidden error-check-and-correction (HECC) scheme compensated the access time penalty caused by the ECC logic on the output critical path. And a multi-column ECC word assignment (MCE) increased the multi-bit-error immunity while using only 1-bit-correctable ECC which minimized area penalty. A source-level-adjusted direct sense amplifier (SLAD) and a write-replica circuit with an asymmetrical replica memory cell (WRAM) for the device-fluctuation-tolerant access control were also designed. A 130-nm CMOS 32-Kbit SRAM-macro was fabricated with these circuit techniques, which demonstrated: 1) 0.3-V operation with 6.8 MHz; 2) 30-MHz operation which is feasible for mobile use even at 0.4 V, while keeping 960MHz at 1.5 V; and 3) a reduction by 3.6/spl times/10/sup 5/ in soft-error rate compared with that of conventional ECC.  相似文献   
8.
Abdominal obesity is the most prevalent manifestation of metabolic syndrome. The anti-obese effects of dietary fiber is generally accepted, but specifically the anti-obese properties of the dietary fiber, gum arabic (GA) has not been well studied. In this investigation, we offered GA to the female 90 days old mice in the form of drink (1% w/v) for 180 days. Such GA in drinking water reduced age-dependent fat deposition in the visceral adipose tissue and improved the gastrocnemius muscle reduction. This inhibition of fat deposition effect is due to the β3-adrenergic stimulation of adipocytes in which TNFα down-regulation is probably involved. Modification of large intestinal microflora, as evidenced by a modification of cecal short-chain fatty acid profile and of 16S rDNA profile, may contribute to such reduction in TNFα expression in the adipose tissues.  相似文献   
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10.
Tetraphenylethylene (TPE) derivatives have strong fluorescence in aggregated state. We report here an oligosaccharide binding assay system using tetraphenylethylene derivatives bearing oligosaccharides with aggregation-induced emission (AIE) characteristics. A tetraphenylethylene derivative bearing 6'-sialyllactose (6'SL) bound to microbeads coated with SSA lectin more effectively than RCA120 lectin. Microbeads that bound to fluorescent oligosaccharide probes could be detected by flow cytometric analysis. Tetraphenylethylene derivatives bearing oligosaccharides are useful for flow cytometric analysis of lectin-oligosaccharide interactions.  相似文献   
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