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Improper processing and storage of raw milk contaminated with Staphylococcus aureusat elevated temperatures can result in the production of staphylococcal enterotoxins, especially type A (SEA), which is most frequently associated with food poisoning outbreaks such as the large one in Osaka, Japan, in 2000. In this study, the characteristics of S. aureusgrowth and SEA production at various high temperatures in raw milk samples were studied using two raw milk samples naturally containing low and high levels of natural microflora. The optimal temperatures found for SEA production in the two milk types were as high as 40 and 44°C (range, 36 to 48°C), and SEA production was dependent on the initial dose of S. aureus.These high temperatures were close to that of the outbreak in Japan. Thus, it was concluded that temperature was critical for SEA production in raw milk. It was also observed that natural microflora in the milk samples considerably suppressed SEA production but not staphylococcal growth. On the other hand, the amount of toxin in most milk samples decreased after peaking during storage.

The effect of grain size on high temperature oxidation behaviour of 316 steels at 700º, 850º and 1000ºC in air was studied. The results show that the mass gain increases with the increase of grain size. Particularly, the gradient of mass gain is severe in at lower oxidation temperatures. In the oxidation at temperatures of more than the solid solution temperature, the grain size before the oxidation changed to coarse grain size. Therefore, in this case, it is not enough to estimate the oxidation behaviour by the grain size before the oxidation. The exfoliation of oxide scale is severe in steel with coarse grains. Over 850ºC, the exfoliation was observed in 316 steel with coarse grains. At 1000ºC, the oxide scale of 316 steel was exfoliated, but it was extreme in the coarse grains. Cr, Mn and Si in the oxide scale were enriched in the oxide scale of the steel with fine grains. Particularly, Si was remarkably enriched at the metal-oxide interface and grain boundaries.

Alternating stacks of metal and dielectric films with nano-hole arrays, called fishnet structures, control the propagation of electromagnetic waves. In such a structure, changing a dimension or a shape, especially the change in shape of nanoholes, affect propagation constants. In this study, we report the dispersivity of fishnet structures is controllable with different hole shapes, by measuring the interferometric fringe in various wavelengths. Two structures were fabricated, which consist of five alternating stacks of aluminum and silicon dioxide with nano-hole arrays. The holes in one of the structures are circular with diameters of 500nm, and the other are square with 500nm sides. The lattice constant in each case is 1,000nm. Since fishnet structures are wavelength-dependent structures, the variable-wavelength interferometric microscope was set up. The phase shift of the circular hole and the square hole fishnet were about 110 degrees and 85 degrees, respectively, within a tunable wavelength from 1,470nm to 1,545nm. These values were equivalent to a refractive-index-change of 0.8 and 0.6, respectively. From these results, fishnet structures indicate high dispersivity within target wavelengths. The dispersion of fishnet structure can be controlled by the shape of the hole.

Changes in crystal phase and electrical properties of oxides composed of Mn, Co, and Ni with the molar ratios of 5:2:1 and 3:3:1 were investigated. Starting oxides were fired from 250°C to 800°C, then maintained at prescribed temperatures for 3 h in air. In the 5:2:1 specimen, a monophase consisting of a cubic spinel oxide that is important to electrical conductivity was obtained at firing temperature of 800°C. In the 3:3:1 specimen, the monophase was obtained at temperatures ranging from 600°C to 800°C. Electrical resistance decreased exponentially with increasing temperature for all specimens fired at temperatures ranging from 250°C to 800°C, indicating that the oxides have intrinsic thermistor characteristics with negative temperature coefficient (NTC). The temperature dependence of the thermistor constant (B value) necessary for practical application was considered to be related to the existence ratio of cubic spinel-type and ilmenite-type structures and the lattice constant of the cubic spinel-type structure. The electrical conduction was stabilized by annealing at prescribed temperatures for more than 720 minutes.

An enhancement in the external quantum efficiency (QE) of red phosphorescent organic light‐emitting devices (OLEDs) by using facially encumbered and bulky meso‐aryl substituted PtIIporphyrin complexes is demonstrated. The maximum external QEs of phosphorescent OLEDs doped with the facially non‐encumbered PtIIporphyrin complex1[5,15‐bis[4‐(4,4‐dimethyl‐2,6‐dioxacyclohexyl)phenyl]‐2,8,12,18‐tetrahexyl‐3,7,13,17‐tetramethylporphyrin platinum(II)], the facially encumbered PtIIporphyrin complex2[5,15‐bis(2,6‐dimethoxyphenyl)‐2,8,12,18‐tetrahexyl‐3,7,13,17‐tetramethylporphyrinato platinum(II)], the PtIIporphyrin complex 3that bears bulkier 3,5‐di‐tert‐butylphenyl substituents [5,15‐bis(3,5‐di‐t‐butylphenyl)‐2,8,12,18‐tetrahexyl‐3,7,13,17‐tetramethylporphyrin platinum(II)], and the “doubly‐decamethylene‐strapped” PtIIporphyrin complex 4were 1, 4.2, 7.3, and 8.2 %, respectively. The trend of increasing QE values in the order of 1< 2< 3< 4may be related to facial encumbrance and steric bulkiness of meso‐aryl substituted PtIIporphyrin complexes. Especially, in the case of the PtIIporphyrin 4, it is considered that the “double straps” play an important role in restricting rotational freedom of the meso‐aryl substituents. The triplet excited‐state lifetimes for PtIIporphyrins 1–4in OLEDs at an injection current density of 0.55 mA cm–2were 80, 103, 140, and 152 μs, respectively. We believe that the trend of increasing triplet lifetime in going from 1to 4is correlated with suppressing non‐radiative decay.

The Cr content of the surface regions of stainless steel tubes that are used as superheaters and reheaters in boilers can be enriched to more than 70 wt-% during chromisation. Such layers are susceptible to the formation of sigma (s) phase while its prevention through the use of chromised Ni plated layers is offset by the occurrence of Kirkendall voids. This paper describes how the microstructure of chromised surface protective Ni-Fe layers can be controlled through the optimisation of the conditions under which the chromising and post-solution heat treatments are carried out. The Ni plating and chromising conditions required for the production of layers in which neither s phase nor Kirkendall void formation takes place are described. The improved chromised surfaces are shown to be highly resistant to hot corrosion, under both coal fired and oil fired environments, as well as to steam oxidation.

ObjectiveTo investigate changes in cytokine expression in the coronary circulation induced by percutaneous transluminal coronary angioplasty (PTCA).MethodsThe study involved 32 patients with ischaemic heart disease who underwent elective PTCA for isolated stenotic lesions of the left coronary artery. Ten patients had plain old balloon angioplasty, 10 had percutaneous transluminal rotational atherectomy, and 12 had stent implantation. Blood samples were drawn from the coronary sinus before and immediately after PTCA. Plasma concentrations of interleukin 6 (IL-6), platelet derived growth factor (PDGF), monocyte chemoattractant protein 1 (MCP-1), and macrophage coronary stimulating factor (M-CSF) were measured. The patients were scheduled for follow up angiography six months after PTCA. Late loss index was calculated using quantitative coronary angiography.ResultsIL-6 concentrations in coronary sinus blood increased immediately after PTCA (p &lt; 0.001), but there was no change in PDGF, MCP-1, or M-CSF. There was a positive correlation between changes in IL-6 concentrations immediately after PTCA and late loss index six months after PTCA (r = 0.73, p &lt; 0.001). IL-6 concentrations in coronary sinus blood were higher in patients with late restenosis than in those without restenosis (p &lt; 0.001).ConclusionsPTCA induces IL-6 production in the coronary circulation. This may induce subsequent inflammatory responses in injured vessels and play an important role in late restenosis after PTCA.

The growth of mould spores of Penicilliumsp. and Cladosporiumsp. inoculated in a commercial mineral water product was studied. The strains had been isolated as fungal foreign bodies in commercial mineral waters. In product A, which was not originally sterilized and was contaminated with psychrophilic bacteria, the inoculated mould spores of the strains did not grow; no increases in viable colony counts or β‐glucans concentration in the samples were observed during storage. In a sterilized product A, inoculated spores of the strains grew into visible foreign bodies. The viable colony counts and the β‐glucans concentration in the samples increased during storage. These results showed that in a sterilized mineral water product, mould spores could grow into visible foreign bodies.

It is important to examine characteristics of ash in order to understand the high temperature corrosion behavior of steels in the black liquor recovery boiler (BLRB) environment. The ash collected from the corroded superheater tubes was mainly composed of alkali-sulfates, alkali-chlorides and alkali-carbonates. The mole ratio of Na/K in the ash from BLRB ranged from 3 to 17. The concentration of sulfates varied over a range from 50 to 90 wt%, and chlorides from 0.1 to 10 wt%. On the base of these results, the corrosion behavior of various steels and the effect of alloying elements on the corrosion behavior of stainless steels in the BLRB environment were studied.From the results, Cr, Mn and Mo were significantly beneficial elements. N and Ni were also beneficial above 600 °C while C was an extremely harmful element. Subsequently, a new corrosion resistant stainless steel was selected as the material for the superheater in the BLRB.

A total of 292 imported and domestic bottled mineral waters (90 brands) obtained from consumers and retailers were examined, by eye, for observable microbial foreign bodies. Fungal and bacterial foreign contaminants were found in 45 samples of water (20 brands) and in 14 samples of water (10 brands), respectively. Of the samples of water found to be contaminated, 41 (22 brands) were imported and 18 (8 brands) were produced domestically. Of 22 brands that were contaminated, 20 (91%) had been sterilized by at least one method. Forty-eight (98%) of 49 samples confirmed with foreign bodies were less than 1 year old. Among the moulds isolated the most predominant genus was Penicillium, followed by Acremonium and Cladosporium. The samples that contained fungi were less contaminated by bacteria than those that contained observable bacterial foreign bodies.

Apoptosis was induced in human glioma cell lines by exposure to 100 nM calphostin C, a specific inhibitor of protein kinase C. Calphostin C-induced apoptosis was associated with synchronous down-regulation of Bcl-2 and Bcl-xL as well as activation of caspase-3 but not caspase-1. The exposure to calphostin C led to activation of stress-activated protein kinase/c-Jun NH2-terminal kinase (SAPK/JNK) and p38 kinase and concurrent inhibition of extracellular signal-regulated kinase (ERK). Upstream of ERK, Shc was shown to be activated, but its downstream Raf1 and ERK were inhibited. The pretreatment with acetyl-Tyr-Val-Ala-Asp-aldehyde, a relatively selective inhibitor of caspase-3, or benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone (z-VAD.fmk), a broad spectrum caspase inhibitor, similarly inhibited calphostin C-induced activation of SAPK/JNK and p38 kinase as well as apoptotic nuclear damages (chromatin condensation and DNA fragmentation) and cell shrinkage, suggesting that caspase-3 functions upstream of SAPK/JNK and p38 kinase, but did not block calphostin C-induced surface blebbing and cell death. On the other hand, the inhibition of SAPK/JNK by transfection of dominant negative SAPK/JNK and that of p38 kinase by SB203580 induced similar effects on the calphostin C-induced apoptotic phenotypes and cell death as did z-VAD.fmk and acetyl-Tyr-Val-Ala-Asp-aldehyde, but the calphostin C-induced PARP cleavage was not changed, suggesting that SAPK/JNK and p38 kinase are involved in the DNA fragmentation pathway downstream of caspase-3. The present findings suggest, therefore, that the activation of SAPK/JNK and p38 kinase is dispensable for calphostin C-mediated and z-VAD.fmk-resistant cell death.

An exotoxin was purified from a toxic shock toxin (TST)-producing Staphylococcus aureus strain, FRI 1169, and another exotoxin was purified from a pyrogenic exotoxin C (PEC)-producing S. aureus strain, 587. Both strains had been isolated from toxic-shock syndrome patients. The two exotoxins were purified by the same method of ion-exchange chromatography, chromatofocusing, and gel filtration. After purification, those exotoxins gave a line of identity against an anti-TST serum and also were immunologically similar to TST in a double-diffusion test. In sodium dodecyl sulfate-polyacrylamide gel electrophoresis, each exotoxin gave a single band with a relative mobility identical to that of the other. Their molecular weights (24,000), isoelectric points (7.0), amino acid compositions, and NH2-terminal amino acid sequences (the first four residues) were identical. Both produced fever and enhanced host susceptibility to lethal endotoxin shock in rabbits, comparable with PEC. These findings show that the two exotoxins are the same protein, which is assumed to be TST. When injected into rabbits, the culture supernatant of strain 587 showed biological activity like that described above, whereas the culture supernatant neutralized with anti-TST immunoglobulin did not. This showed that PEC-producing strain 587 does not produce any toxin with these biological activities in rabbits except TST.

Three series of experiments were conducted to collect information for the design of a commercial scale reactor for the production of low cost vapor grown carbon fibers (VGCFs). Firstly, the effects of reaction conditions on the yield of vapor grown carbon fibers were investigated using the newly developed liquid pulse injection technique. The examined conditions were the flow rate of the carrier gas, and the amount of the catalyst source injected into the reactor as a liquid pulse. Yields up to 40% were attained under optimized conditions. Secondly, VGCFs were continuously produced by intermittently injecting the catalyst source into the reactor (intermittent liquid pulse injection technique), and the effect of the intervals of the injections on the amount of VGCFs obtained was also investigated. VGCFs were successfully obtained using this method. Finally, the growth sequences of VGCFs were investigated using benzene, toluene and xylene as the carbon source. VGCFs were obtained from each carbon source

The corrosion behavior of various austenitic stainless steels and high-alloy steels has been studied in simulated fluidized bed boiler environment to develop a new corrosion resistant austenitic stainless steel for the superheater tube. The superheater is usually not installed within the bed position, which is different from the evaporator installed within the bed position. Therefore, the superheater tubes are exposed to an oxidizing environment; but it is also necessary to estimate the corrosion resistance of the steels in a reducing environment. It is already known that the high temperature corrosion behavior in conditions where CaSO4 is coated on the steels is more important than the erosion of the superheater tubes. The main results in this present study are as follows: The Nb bearing steels and low C steels showed good resistance to high-temperature corrosion in CaSO4 /CaO, e.g. 347, 304L and HR3C. The corrosion rate of all steels used increased with increase in temperature, particularly at temperatures higher than 650°C. Internal penetration was not detected at temperatures lower than 550°C, but it was detected at temperatures higher than 600°C, in particular, higher than 650°C. The corrosion thickness loss was almost the same as the internal penetration depth at 700 and 750°C in the 300 series steels placed in CaSO4/CaO, including the fine grained 347 steel, while the internal penetration depth was larger than the corrosion thickness loss in high-alloyed materials such as Alloy 800 and 310 steels. At temperatures higher than 800°C, the same result was also obtained for the fine grained 347 steel. The corrosion during exposure to oxidizing or reducing gases without CaSO4/CaO or CaS was slight, but when the test specimens were placed in CaSO4/CaO or CaS, the corrosion rate sharply increased, regardless of the atmospheric gas composition. Cr, Si, Mn (less than 5 %), Mo and Nb are beneficial elements while C, Cu and Al are harmful elements. From the above results, the following steel was developed for high temperature corrosion resistance in CaSO4/CaO: low C-22/25Cr-17/25Ni-3/5Mn-(2Mo)-Nb-0.08/0.2N-Al-(B).

A grain refining process has been developed for TP347H tubes, where grain size as fine as GS No. 8 can be obtained even at higher solution treating temperatures. Grain refinement is caused by the precipitation of fine NbC carbides during solution treatment.

A reversed passive latex agglutination method, in which latex particles were sensitized with specific anti-toxic shock syndrome toxin-1 (TSST-1) immunoglobulin, was found to be a simple and sensitive method for the detection of TSST-1 production by Staphylococcus aureus strains. The minimum amount of TSST-1 detectable was approximately 1.0 ng/ml. Of 41 S. aureus isolates from toxic shock syndrome patients and controls, 23 were positive for TSST-1 production, whereas only 20 strains were positive for TSST-1 production by an Ouchterlony immunodiffusion method. The reversed passive latex agglutination method was used to examine S. aureus strains isolated in Japan from staphylococcal infections, feces from healthy individuals, food from poisoning outbreaks, and market food.

Abstract ObjectiveTo determine whether inhibition of angiotensin converting enzyme (ACE) can prevent angiotensin II production in the coronary circulation induced by percutaneous transluminal coronary angioplasty (PTCA) in patients with myocardial ischaemia. Design, patients41 patients who underwent elective PTCA and six control subjects who received diagnostic coronary angiography were studied. Patients were divided into two groups according to the chronic administration of ACE inhibitors (group A, 15 patients treated with ACE inhibitors; group B, 26 patients without ACE inhibitors). Blood samples were drawn through catheters placed in the aorta and coronary sinus before and 24 hours after PTCA. ResultsMean levels of ACE activity in the aorta were significantly lower in patients in group A than in group B. However, mean angiotensin II concentrations in the aorta were not significantly different between the two groups. Differences in basal angiotensin II concentrations between the coronary sinus and aorta, which reflected basal angiotensin II production in the coronary circulation, were not significant among group A, group B, and control subjects. The production of angiotensin II in the coronary circulation was significantly increased 24 hours after PTCA in both group A and group B to the same extent. No significant changes were observed in control subjects 24 hours after diagnostic coronary angiography. ConclusionsThis study revealed that inhibition of ACE activity by ACE inhibitors could not prevent increases in angiotensin II production in the coronary circulation induced by PTCA.

On treatment of the benzoxastibole(V) (I) with MeLi at ‐78 °C, the only adduct (IIa) is formed which at increasing temp. equilibrates with its isomers (IIb) and (IIc).

The title 12‐Sb‐6 ate complexes such as (I) (8 examples, all formed from a 10‐Sb‐5 compound and organolithiums) are obtained at ‐78 °C as a single isomer (structure shown in the scheme).

It is well known that cellulolytic enzymes hardly attack lignocellulose. Hitherto knowledge, however, has not yet fully elucidated the mechanisms of the inhibition; whether it depends on a steric hindrance or protein-binding inhibition. For the purpose of acceleration of enzymatic digestion of lignocellulose biomass, the study was carried out using partially purified cellulase of Meicelase and milled wood lignin from soft or hard wood.

A detailed discussion based upon Oseen's equations of motion has been made of the steady two-dimensional flow of a viscous fluid passing perpendicularly through an infinite row of equal parallel circular cylinders regularly spaced. It has thus been found that the drag acting on any one of the cylinders in the row is always greater than that acting on the same cylinder when it is immersed alone in an unlimited uniform flow with the same velocity. In particular, when the Reynolds number of the flow is sufficiently small, the drag is found to be proportional to the flow speed U, while it is proportional to U/log U in the case of a single cylinder. Thus, the interference effect between the cylinders in the row is very remarkable at low Reynolds numbers.