Application of random amplified polymorphic DNA analysis for detection of Salmonella spp. in foods

The random amplified polymorphic DNA (RAPD) band patterns from 23 Salmonella spp. produced by use of an oligonucleotide primer (called du primer) designed on the basis of the N-terminal sequence of dulcitol 1-phosphate dehydrogenase (5'-GTGGTGACCCAGGATGGCCAGGTG-3') were different from those from 16 non-Salmonella spp. The bands at 460 and 700 bp were produced in all Salmonella strains tested. These RAPD fragments obtained from Salmonella typhimurium strongly hybridized with the corresponding RAPD bands from the other strains of Salmonella, but not with those from non-Salmonella spp. in Southern blot analysis. The RAPD bands were detected by ethidium bromide staining even when genomic DNA prepared from as few as 2.8 x 10(3) cells was used. The minimum detectable cell number in the initial inoculum of S. typhimurium was 4 x 10(-1) CFU/25 g of raw beef after the preenrichment in Enterobacteriaceae enrichment mannitol (EEM) broth for 6 h and the selective enrichment in dulcitol-magnesium chloride-pyridinesulfonic acid-brilliant green-novobiocin (DMPBN) medium for 18 h at 42 degrees C. Seven raw foods inoculated with S. typhimurium at numbers from 4 x 10(-1) to 2.6 x 10(2) CFU/25 g of food were positive in both the RAPD analysis and the conventional culture method.     

Antiproliferative constituents in umbelliferae plants. III. Constituents in the root and the ground part of Anthriscus sylvestris Hoffm

To test whether mitogen-activated protein kinases (MAPKs) are involved in microglial activation, pure microglia prepared from 1- to 3-day-old rat brains were activated with either 100 ng/ml lipopolysaccharide (LPS) or 5 nM synthetic beta-amyloid (Abeta) (25-35). The patterns of MAPK activation following LPS and Abeta treatment were very similar. Three MAPK subtypes, p38, extracellular signal-regulated kinase (ERK) and c-Jun N-terminal kinase/stress-activated protein kinase (JNK/SAPK) were activated within 15 min and the activities of p38 and ERK were rapidly reduced to background level within 30 min while that of JNK was maintained for over 1 h. Both inhibitors of p38 (SB203580) and ERK pathway (PD098059) reduced LPS-induced nitric oxide (NO) release and Abeta-induced tumor necrosis factor-alpha (TNF-alpha) release. Furthermore, co-treatment of SB203580 and PD098059 additively reduced NO and TNF-alpha release. These results suggest that MAPK, at least p38 and ERK, mediate LPS-, and Abeta-induced microglial activation.     

Transient response of a grounding system in an underground GIS substation

The transient grounding impedance of a gas‐insulated switchgear (GIS) substation was investigated through measurements on a commercial 300‐kV underground substation. Using the results, the transient impedance of the grounding grid was investigated. The attenuation factor of the propagation line composed of the outer surface of the GIS tank and the concrete floor was also evaluated. The validity of EMTP analysis of surge phenomena in the GIS grounding system was confirmed. © 2003 Wiley Periodicals, Inc. Electr Eng Jpn, 146(1): 70–77, 2004; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10214     

Observation of lightning phenomena on distribution lines using composite techniques

For the rationalization of lightning protection design of distribution lines, it is important to clarify the behavior of distribution lines when direct or nearby lightning occurs. Because of the lower insulation level than for transmission lines, in studies on lightning protection design of distribution lines, not only direct lightning strokes but also induced voltages caused by nearby strokes must be taken into account. Thus, it is necessary to grasp the frequency of occurrence on lightning phenomena around distribution lines. For this aim, lightning phenomena on TEPCO's distribution lines in use had been continuously observed for 6 years (1996 to 2001). The observation was carried out in a composite way, using still cameras and sensor for acquisition of lightning surge waveform data. Through the observation, new phenomena about lightning performance on distribution lines in the field became apparent. In some cases, in spite of a direct strike to the line, flashover did not occur. This fact means that the distribution line has a certain level of lightning resistance. Moreover, it was confirmed that AC following current generated between both ends of insulator disappeared naturally. These results are interesting discoveries that can be useful in estimating the fault ratio precisely. © 2006 Wiley Periodicals, Inc. Electr Eng Jpn, 157(1): 10–19, 2006; Published online in Wiley InterScience ( http://www.interscience.wiley.com ). DOI 10.1002/eej.20164     

Insulation characteristics of GIS under nonstandard lightning‐impulse oscillations: Insulation characteristics under single‐frequency oscillations with various frequencies and damping ratios

To improve GIS insulation specifications, it is important to recognize the insulation characteristics under oscillatory overvoltage waveforms occurring in the field. This paper describes investigations of insulation characteristics for single‐frequency oscillatory waveforms with various frequencies and damping ratios. It was found that minimum breakdown voltages (V_min) rose with frequency rising under the same damping condition and V_min rose with damping ratio rising under the same frequency condition. From an analysis of actual breakdown voltage characteristics, the probability of breakdown at a valley of oscillation rose with damping increasing. It was found that the insulation characteristics were treated all‐inclusively based on the characteristics of V_min for rise time or damping time. © 2003 Wiley Periodicals, Inc. Electr Eng Jpn, 145(3): 43–49, 2003; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10156     

Left ventricular function of the heart regressed by nifedipine in spontaneously hypertensive rats

The clinical course of lens opacity and the morphological changes in lens epithelial cells after intravitreal silicone oil injection were observed for 3 months in 21 normal adult albino rabbits. After the simple vitrectomy in both eyes of each rabbit, silicone oil was injected into the vitreous in one eye and the other eye was kept as the control. By photoslit-lamp microscopy, 8 of the 14 examined eyes showed early posterior subcapsular lens opacity one month after silicone oil injection. By transmission electron microscopy, intracellular vesicles near the interdigitation of the lens epithelial cells were observed in all of the 7 eyes examined histologically 2 weeks after the procedure. These changes were not observed in the 7 fellow control eyes. As a result, it is surmised that cataract formation after intravitreal silicone oil injection may be associated with morphological changes in the lens epithelial cells.     

The precipitation of Ni3S2 from sulfate solutions

The formation conditions for the recovery of nickel from sulfate solutions as Ni3S2 have been investigated; this sulfide is more reactive than NiS in subsequent leaching operations. Hydrogen sulfide gas at atmospheric pressure is introduced into a NiSO4-Na2SO4-MgSO4-Al2(SO4)3 solution in the presence of reduced iron powder. Although the formation of Ni3S2 is compctitive with that of NiS, the nickel precipitation efficiency and the ratio of nickel as Ni3S2 to the total nickel precipitated reached 99.5 to 99.9 and 90 to 95 pct, respectively, under the following conditions: 363 K, Ph2s 31 kPa, Ni²⁺ 4.0 g · dm^-3, 3[Fe^o]/[Ni²⁺] 1.25 to 1.5, H2S flow rate 70 to 100 cm³ · min^-1, and 45 to 60 minutes retention time. Selective formation of Ni3S2 is achieved within 10 minutes, and a reaction on the surface of the iron is rate-determining during the early stages of precipitation. Since the iron is almost totally consumed after 1 to 2 hours of reaction, the precipitated Ni₃S₂ is gradually converted to NiS. Calculations considering the buffer action of sulfate ion and sulfate complex formation with polyvalent metal cations as well as with nickel ions confirmed that significant nickel precipitation as Ni₃S₂ should occur under the test conditions.     

A 500 MHz, 32 bit, 0.4 μm CMOS RISC processor

A 500 MHz, 32 bit RISC microprocessor has been experimentally developed using an 8-stage pipelined architecture and high-speed circuits, including a 500 MHz 1 kilobyte double-stage pipelined cache, a 1.8 ns register file, a double-stage binary look-ahead carry (BLC) adder circuit, and a 500 MHz phase locked loop (PLL) frequency multiplier. Newly developed circuit-integrating techniques include a stacked power-line structure, which serves as a noise shield and also provides low bounce, a low voltage-swing interface circuit with on-chip adjustable termination resistors, a small-skew clock distribution method, and a clock synchronization circuit which provides small-skew clock among LSI chips. About 200000 transistors are integrated into a 7.90 mm×8.84 mm die area with 0.4 μm CMOS fabrication technology. Power dissipation is 6 W at a 500 MHz operation and 3.3 V supply voltage     

The synthesis and microstructure of morph-genetic TiC/C ceramics

Wood is a natural material with a novel and ordered hierarchical structure. In the present work, it is used as a bio-template to produce morph-genetic TiC/C ceramics. This is obtained by infiltrating the carbon preform pyrolyzed from wood with tetrabutyl titanate. It was subsequently sintered at 1400 °C to produce the final ceramic structure.By observing the microstructure under the scanning electron microscope and the transmission electron microscope, the morph-genetic TiC/C ceramics are shown retaining the complex morphology of the original template structure. The crystalline TiC was formed through the reaction of tetrabutyl titanate with carbon preform, and it was distributed mainly at the surface layer of the cellular wall. During the conversion of wood into carbon preform, the specific surface area of samples increased from 28.2 to 35.7 m² g⁻¹, and its porosity also increased from 64.4% to 80.3%. However, during the conversion of carbon preform into morph-genetic ceramics, the specific surface area of samples decreased from 35.7 to 33.8 m² g⁻¹, and its porosity also decreased from 80.3% to 76.5%. At the synthesis process, the variation of pore-size distribution is mainly in the range from 0.1 to 1 μm.     

Preparation and characterization of oil-in-water type poly (D,L-lactic acid) microspheres containing testosterone enanthate

Interstitial fluid pressurization has long been hypothesized to play a fundamental role in the load support mechanism and frictional response of articular cartilage. However, to date, few experimental studies have been performed to verify this hypothesis from direct measurements. The first objective of this study was to investigate experimentally the hypothesis that cartilage interstitial fluid pressurization does support the great majority of the applied load, in the testing configurations of confined compression creep and stress relaxation. The second objective was to investigate the hypothesis that the experimentally observed interstitial fluid pressurization could also be predicted using the linear biphasic theory of Mow et al. (J. Biomech. Engng ASME, 102, 73-84, 1980). Fourteen bovine cartilage samples were tested in a confined compression chamber fitted with a microchip piezoresistive transducer to measure interstitial fluid pressure, while simultaneously measuring (during stress relaxation) or prescribing (during creep) the total stress. It was found that interstitial fluid pressure supported more than 90% of the total stress for durations as long as 725 +/- 248 s during stress relaxation (mean +/- S.D., n = 7), and 404 +/- 229 s during creep (n = 7). When comparing experimental measurements of the time-varying interstitial fluid pressure against predictions from the linear biphasic theory, nonlinear coefficients of determination r2 = 0.871 +/- 0.086 (stress relaxation) and r2 = 0.941 +/- 0.061 (creep) were found. The results of this study provide some of the most direct evidence to date that interstitial fluid pressurization plays a fundamental role in cartilage mechanics; they also indicate that the mechanism of fluid load support in cartilage can be properly predicted from theory.