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101.
A vector unit for high-performance three-dimensional graphics computing has been developed. We implement four floating-point multiply-accumulate units, which execute multiply-add operations with one throughput; one floating-point divide/square root unit, which executes division and square-root operations with six cycles at 300 MHz; and one vector general-purpose register file, which has 128 bits×32 words. The parallel execution of all units delivers a peak performance of 2.44 GFLOPS at 300 MHz  相似文献   
102.
It has been reported that cellular oxidative stress induces apoptosis, that may be inhibited by scavengers of reactive oxygen intermediates (ROIs). Superoxide dismutase (SOD) is among the most active scavengers of ROIs, providing defense against the cellular oxidative stress. Fas antigen and tumor necrosis factor (TNF) receptor are the cell surface proteins, stimulation of which induces apoptosis of keratinocytes. Using SV40-transformed human keratinocytes (SVHK cells), we investigated the effects of anti-Fas antibody and TNF-alpha on the SOD activity. Treatment of SVHK cells with anti-Fas antibody or TNF-alpha in the presence of interferon-gamma (IFN-gamma) resulted in an increase in Mn-SOD activity, Cu,Zn-SOD activity was not affected. In the absence of IFN-gamma, no increase in Mn-SOD activity was detected. The induction of IFN-gamma-dependent Mn-SOD activity by anti-Fas antibody or TNF-alpha was concentration-dependent; the maximal effect was observed at 1-10 micrograms/ml and 5-10 ng/ml, respectively. The increase in Mn-SOD activity was observed at 6 h following the treatment and remained for at least 48 h. Northern blot analyses showed that Mn-SOD mRNA increased within 3 h without a significant change in Cu,Zn-SOD mRNA. The addition of both anti-Fas antibody and TNF-alpha in the presence of IFN-gamma resulted in an additive increase in Mn-SOD activity. Although the addition of 12-o-tetradecanoylphorbol-13-acetate (TPA) singly to the incubation medium had no effect on either Mn-, or Cu,Zn-SOD activity, it significantly augmented the IFN-gamma-dependent induction of Mn-SOD activity by anti-Fas antibody or by TNF-alpha. The protein kinase C inhibitor, 1-(5-isoquinoline-sulfonyl)-2-methyl piperazine dihydrochloride (H-7), significantly inhibited the TPA-dependent increase in Mn-SOD activity. These results indicate that the stimulation of Fas antigen or TNF receptor increases Mn-SOD activity of SVHK cells in the presence of IFN-gamma and that TPA augments the process through the activation of protein kinase C.  相似文献   
103.
In this correspondence, a modified version of Hunt's (1980) image model is used to interpret the distribution of image data vectors. The model suggests that the diagonal line of the coordinates system is a good approximation of the principal axis of the image data vector set. The validity of the model is supported by experiments. Following this suggestion, an effective nearest neighbor search method for vector quantization of image data is developed. The method is based on partitioning the vector space using hyperplanes which are perpendicular to the diagonal direction of the coordinate system. The validity of the method is assessed by analyzing its complexity and comparing its performance to those of existing algorithms on a number of images.  相似文献   
104.
In a double-blind, multicentre study 245 children aged 1-10 yr undergoing elective minor surgery as inpatients were randomly allocated to receive a single caudal extradural injection of 1 ml kg-1 of either 0.25% bupivacaine or 0.2% ropivacaine after induction of light general anaesthesia. The groups were comparable for age, weight, vital signs and duration of surgery. The onset time was similar for ropivacaine and bupivacaine (9.7 vs 10.4 min). Further analgesia was not required in 40% of children. The mean time to first analgesia in the remainder was 233 min in the bupivacaine group and 271 min in the ropivacaine group. No motor block was measurable in either group. Ropivacaine 2 mg kg-1 was as effective as bupivacaine 2.5 mg kg-1 for caudal analgesia in children.  相似文献   
105.
Structures of silica nanoparticles coated with stereocomplex thin films composed of isotactic (it) poly(methyl methacrylate) (PMMA) and syndiotactic (st) poly(methacrylic acid) (PMAA) and with porous it-PMMA thin films under gentle stirring or static conditions were analyzed by dynamic light scattering (DLS) and scanning electron microscopy (SEM), respectively. The porous it-PMMA films were fabricated by stepwise stereocomplex assembling of it-PMMA and st-PMAA, and subsequent extraction of the st-PMAA from the films. From DLS results, an evident difference was not observed between the it-PMMA films and the stereocomplex films, whereas the it-PMMA films after 10 h of stirring in acetonitrile/water (4/6, v/v) and drying on a SEM stage fused to form nanostructured networks. The fusion of the it-PMMA films on the silica nanoparticles occurred not by the dissolution of it-PMMA in the mixed solvent, but rather by an interaction of the it-PMMA chains driven by the slight solvation of acetonitrile without dissolution. Thus, leaving the solution at rest would be important for film fusion on the particles, and multiple spherical substrates could promote the crosslinking of the it-PMMA chains on the particles.  相似文献   
106.
Cellular microenvironments are generally sophisticated, but crucial for regulating the functions of human pluripotent stem cells (hPSCs). Despite tremendous effort in this field, the correlation between the environmental factors—especially the extracellular matrix and soluble cell factors—and the desired cellular functions remains largely unknown because of the lack of appropriate tools to recapitulate in vivo conditions and/or simultaneously evaluate the interplay of different environment factors. Here, a combinatorial platform is developed with integrated microfluidic channels and nanofibers, associated with a method of high‐content single‐cell analysis, to study the effects of environmental factors on stem cell phenotype. Particular attention is paid to the dependence of hPSC short‐term self‐renewal on the density and composition of extracellular matrices and initial cell seeding densities. Thus, this combinatorial approach provides insights into the underlying chemical and physical mechanisms that govern stem cell fate decisions.  相似文献   
107.
Described is a silica-based athermal 100 GHz-spacing 40-channel arrayed waveguide grating (AWG) with a Mach-Zehnder interferometer (MZI)-synchronised configuration that employs resin-filled grooves in the AWG and MZI. By suppressing the groove excess loss and using 1.5%-Delta waveguides, a low insertion loss of 3.2 dB and a wide 0.5 dB bandwidth of 45.9 GHz with athermal operation in the -5 to 65degC range and a compact chip size were achieved.  相似文献   
108.
A single 3.3-V only, 8-Gb NAND flash memory with the smallest chip to date, 98.8 mm2, has been successfully developed. This is the world's first integrated semiconductor chip fabricated with 56-nm CMOS technologies. The effective cell size including the select transistors is 0.0075 mum2 per bit, which is the smallest ever reported. To decrease the chip size, a very efficient floor plan with one-sided row decoder, one-sided page buffer, and one-sided pad is introduced. As a result, an excellent 70% cell area efficiency is realized. The program throughput is drastically improved to twice as large as previously reported and comparable to binary memories. The best ever 10-MB/s programming is realized by increasing the page size from 4kB to 8kB. In addition, noise cancellation circuits and the dual VDD-line scheme realize both a small die size and a fast programming. An external page copy achieves a fast 93-ms block copy, efficiently using a 1-MB block size  相似文献   
109.
Endothelin (ET)-1 reduced heparin-releasable lipoprotein lipase (LPL) activity in 3T3-L1 adipocytes in a concentration-dependent manner. However, a selective ETB receptor agonist, [Ala1,3,11,15]ET-1, did not act like ET-1. The ET-1-induced decrease in LPL activity was suppressed by a selective ETA receptor antagonist, BQ-123: the concentration-response curve for the ET-1 reduction of LPL activity was shifted to the right in the presence of BQ-123 in a concentration-dependent manner. This antagonistic effect of BQ-123 clarifies that the ETA receptor is responsible for the ET-1-induced reduction of LPL activity in 3T3-L1 adipocytes, which suggests that there is therapeutic potential for ETA antagonists in LPL-related lipoprotein disorders.  相似文献   
110.
BACKGROUND: Epidemiologic studies have shown alcohol consumption to be inversely as well as positively related to body weight and body fat. Metabolic studies have shown an increase in energy intake as well as compensation after alcohol consumption. OBJECTIVE: Our objective was to assess the effects on energy intake of an apéritif compared with those of a water appetizer and 3 fruit juice appetizers. DESIGN: Fifty-two men and women aged 20-45 y with a body mass index (in kg/m2) between 20 and 32 were randomly given 1 MJ (340 mL) alcohol (wine or beer), fat (cream fruit juice), protein (protein fruit juice), carbohydrate (grape juice), or water, or no preload 30 min before an ad libitum lunch consumed from the universal eating monitor. RESULTS: Energy intake (3.5+/-0.3 MJ compared with 2.7+/-0.2 MJ, P < 0.001) and eating rate were higher (44+/-3 g/min compared with 38+/-3 g/min, P < 0.01), meal duration was longer (14 min compared with 12.0 min, P < 0.01), satiation started to increase later (3.5 min compared with 1.5 min, P < 0.01), and eating was prolonged after maximum satiation (2.5 min compared with 0.6 min, P < 0.01) after an apéritif than after a fat, protein, or carbohydrate appetizer,. Twenty-four-hour energy intake was higher on a day that an apéritif was consumed than after water or no preload. CONCLUSION: Twenty-four-hour energy intake was elevated with a 1-MJ apéritif but not with a 1-MJ liquid carbohydrate, fat, or protein appetizer.  相似文献   
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