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A high-resolution liquid chromatography-Orbitrap mass spectrometry (LC-Orbitrap MS) method was developed for simultaneous determination of 20 Fusarium toxins (nivalenol, fusarenon-X, deoxynivalenol, 3-acetyl deoxynivalenol, 15-acetyl deoxynivalenol, HT-2 toxin, T-2 toxin, neosolaniol, diacetoxyscirpenol, fumonisin B1, fumonisin B2, fumonisin B3, fumonisin A1, fumonisin A2, fumonisin A3, zearalenone, α-zearalenol, β-zearalenol, α-zearalanol, and β-zearalanol) in cereals. The separation of 20 Fusarium toxins with good peak shapes was achieved using a pentafluorophenyl column, and Orbitrap MS was able to detect accurately from cereal matrix components within ±0.77 ppm. The samples were prepared using a QuEChERS kit for extraction and a multifunctional cartridge for purification. The linearity, repeatability, and recovery of the method were &gt, 0.9964, 0.8%–14.7%, and 71%–106%, respectively. Using this method, an analysis of 34 commercially available cereals detected the presence of deoxynivalenol, 15-acetyl deoxynivalenol, fumonisin B1, fumonisin B2, fumonisin B3, fumonisn A1, fumonisin A2, fumonisin A3, and zearalenone in corn samples with high concentration and frequency. Trichothecenes was detected from wheat samples with high frequency, in particular, the concentration of deoxynivalenol was high. Conversely, α-zearalenol, β-zearalenol, α-zearalanol, and β-zearalanol were not detected in any of the samples.

A method for the simultaneous analysis of 14 mycotoxins with the minimization of carryover was developed. Our verification experiments suggested that the carryover occurred due to the chelation of fumonisins with the metal. To wash the fumonisins from the metal, the inner surface of the injection needle was rinsed with 10 mM trisodium citrate and 1% formic acid in water/methanol/acetonitrile/isopropanol after each injection, and the analysis was performed on a metal-free Mastro C18 column. This approach remarkably minimized the carryover of fumonisins. Fourteen mycotoxins in samples were extracted with 2% acetic acid in water/acetonitrile and a quick, easy, cheap, effective, rugged, and safe extraction kit, purified on a MultiSep 229 Ochra, and then quantified by liquid chromatography with tandem mass spectrometry. Determinations performed using this method produced a linearity greater than 0.99 and recoveries ranging from 72.6 to 117.4%, with good intraday precision from 4.0 to 12.4%, and interday precision from 6.5 to 17.0%. The limits of detection ranged from 0.01 to 0.71 μg/kg, demonstrating that a highly sensitive method for the simultaneous analysis of mycotoxins over a wide range of concentrations was achieved with minimal carryover. When 12 samples of commercially available corn grits were analyzed with this method, deoxynivalenol, fumonisin B1, fumonisin B2, fumonisin B3, and zearalenone were present most frequently.

We developed a method for simultaneous analysis of nine trichothecenes (nivalenol, deoxynivalenol, fusarenon-X, neosolaniol, 3-acetyldeoxynivalenol, 15-acetyldeoxynivalenol, diacetoxyscirpenol, HT-2 toxin, and T-2 toxin). Trichothecenes in samples were extracted with acetonitrile-water (1 : 1) and purified using a QuEChERS kit and a multi-functional cartridge. Then they were quantified by LC-MS/MS using internal standards. LC with a pentafluorophenyl column and a mobile phase containing methanol enabled complete separation and highly sensitive quantification of the nine trichothecenes. Method validation with powdered corn soup samples demonstrated high linearity (>0.99) and accuracy ranging from 95% to 111% with good repeatability of 0.9% to 6.6% and reproducibility of 0.6% to 11.6%. The limits of detection and quantification were 0.01 to 0.75 μg/kg and 0.04 to 2.50 μg/kg, respectively. When 15 samples from powdered corn soups on the market were analyzed with this method, deoxynivalenol was detected in two samples (20.7 and 22.5 μg/kg, respectively), and 3-acetyldeoxynivalenol was concomitantly detected in one of them (13.5 μg/kg).

To achieve reliable transmission of detonation waves to a pulse detonation engine combustor (detonation chamber), the authors propose a pulse detonation engine initiator that uses a cylindrical reflector downstream of a predetonator exit. The detonation wave propagates around the reflector to change the wave shape in three transition stages: from a planar detonation wave in the predetonator to an expanding cylindrical detonation wave, from the cylindrical wave to a planar toroidal detonation wave, and from the toroidal wave to a planar detonation wave in the detonation chamber. The cylindrical wave propagates along a cylindrical path between the reflector and front wall of the detonation chamber, and the toroidal wave propagates along an annular path between the reflector and sidewall of the detonation chamber. The purpose of this study was to examine the influence of the gap width L of the annular path on the transition stages from cylindrical to toroidal and from toroidal to planar. A series of experiments that filled the entire test section with the driver gas mixture (stoichiometric hydrogen oxygen mixture) showed that the expanding cylindrical detonation wave was sufficiently strong to survive the rarefaction waves from the corners of the reflector at all of the investigated annular gap widths (5, 10, 15, and 20 mm) and was transmitted to the planar toroidal wave successfully in all cases. When the strength of the cylindrical detonation wave was under a supercritical condition for diffraction at the reflector corner, the necessary filling distance for the driver gas was predicted well by the Whitham theory. A second series of experiments showed the influence of the annular gap width on the detonation transition from the planar toroidal detonation wave to the planar detonation wave. Two different types of detonation transitions termed "continuous transition" and "temporal quenching" were observed. The threshold value of L/lambda for continuous transition is approximately four.

A chromanone glycoside, 5-β- d -glucopyranosyloxy-7-hydroxy-2-isopropylchromanone, and two acylphloroglucinol glycosides, 2-(3-methylbutyryl)phloroglucinol-4,6-di-C-β- d -glucopyranoside and 2-isobutyrylphloroglucinol-1,5-di-O-β- d -glucopyranoside, along with 15 known compounds were isolated from the bracts of hops (Humulus lupulus L.). Their structures were elucidated based on spectroscopic data, including TOFMS and 1D/2D NMR.

An analytical method using two solid phase extractions and ultra-high-performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS) was developed for the identification and quantification of 14 mycotoxins (patulin, deoxynivalenol, aflatoxins B1, B2, G1, G2, M1, T-2 toxin, HT-2 toxin, zearalenone, fumonisins B1, B2, B3, and ochratoxin A) in domestic and imported wines. Mycotoxins were purified with an Oasis HLB cartridge, followed by a MultiSepTM #229 Ochra. As a result, sufficient removal of the pigments and highly polar matrices from the red wines was achieved. UHPLC conditions were optimized, and 14 mycotoxins were separated in a total of 13 min. Determinations performed using this method produced high correlation coefficients for the 14 mycotoxins (R > 0.990) and recovery rates ranging from 76 to 105% with good repeatability (relative standard deviation RSD < 12%). Twenty-seven samples of domestic and imported wines were analyzed using this method. Although ochratoxin A (OTA) and fumonisins (FMs) were detected in several samples, the FM levels were less than limits of quantification (LOQs) (1 μg/L), and even the largest of the OTA levels was below the EU regulatory level (2 μg/L). These results suggest that the health risk posed to consumers from the wines available in Japan is relatively low.

To reduce driver gas usage of a pulse detonation engine operating in airbreathing mode, the authors experimentally examined a combination method of a reflecting board and overfilling of the driver gas. This method has the potential to reduce the predetonator diameter by half and shorten the overfilling distance h to the reflecting board position w. Experiments with stoichiometric hydrogen–oxygen and hydrogen–air mixtures as driver and target gases, respectively, showed that the overfilling distance necessary to have a planar detonation wave propagate in a detonation chamber is reduced to 30 mm when a reflecting board is used with a reflecting board clearance of w 10 mm. With an overfilling distance of 30 mm, the transformation of the detonation wave from cylindrical to toroidal did not occur because of the mixing effect of the driver gas and the target gas around the reflecting board. A 100-mm-thick reflecting board prevents the mixing effect, and a successful transformation from cylindrical to toroidal becomes possible with an overfilling distance as small as 17.2 mm.

An HPLC method with a charged aerosol detector (CAD) was optimized and validated for the quantification of six carbohydrates (xylose, fructose, glucose, sucrose, lactose, maltose) and sugar alcohol (erythritol) in drinks. Chromatographic separation was achieved using gradient elution with a mixture of water-methanol (7 : 3) and acetonitril. Carbohydrates were cleaned up using a strong cation exchange cartridge (Bond Elut SCX, Varian). Although an interfering peak appeared without any clean up, it was confirmed that interfering substance had be removed by a treatment using this cartridge and its peak had disappeared. The determinations were performed in the linear range of 5 ∼ 10000 μg/mL for six carbohydrates and sugar alcohol, the correlation coefficients (R) were 0.998 ∼ 1.000, the relative standard deviations (RSDs) ranged over 0.4 ∼ 4.5% (spiked level at 500 μg/mL, n = 5), recoveries ranged between 84 ∼ 113% (spiked level at 500 μg/mL, n = 3), and the limits of quantification were 0.4 ∼ 19.3 μg/mL. In addition, we performed analysis of carbohydrates with CAD, an evaporative light scattering detector (ELSD) and a refractive index detector (RID) to compare and investigate the sensitivity and analysis precision in the each optimum condition. As for the CAD, high sensitivity and good analysis precision were provided. Because it is not necessary to optimize the conditions, CAD is the simplest and easiest device in these detectors. It became clear that CAD was the most suitable to perform correct quantitative analysis of carbohydrates in drinks.

The paper presents an embedded control software development environment that provides a tool to verify the data consistency of embedded control software designed with Simulink models and UML models. A controller model is built with MATLAB/Simulink in the control logic design phase. Then a software model that correctly executes the control logic in the actual computing environment is built in the software design phase. It must be verified during software design that the data consistency of the software is preserved in the preemptive multitask environment because the simulation of Simulink models is performed in an ideal environment in which "zero-time execution" is assumed. We present a method to verify the data consistency with SPIN model checker. We also present a tool that automatically generates Promela code for data consistency verification. We have applied the tool to a number of software models transformed from Simulink models and have confirmed its usefulness for embedded control software design. Keywords—embedded control software, real-time systems, model-based design, verification, model checking

A new method was established for the simultaneous determination of 10 sweeteners and a degradation product in beverages by using LC-MS/MS. An ACQUITY UPLC BEH C18 (2.1 × 100 mm, 1.7 μm) was used as the LC column and 0.1% each of aqueous formic acid and formic acid in acetonitrile were used as the mobile phase. A simple and rapid determination of sweeteners was possible by diluting with a solvent, and in the case of some samples containing a large amount of foreign matter, after pre-treatment by diluting with solvent and clean-up of the sample using an Oasis HLB cartridge. All the validation results were satisfactory. As the regulations and standards for sweeteners vary from country to country, a field survey of 58 beverages marketed in Japan was performed using the present method. No issues concerning the labelling or food sanitation law were found in the tested samples.

1. Two types of Genji firefly, Luciola cruciata, have been recognised on the basis of the inter-flash interval. 2. The fast-flash and slow-flash type fireflies, distributed in the western and eastern parts of Japan, exhibit a 2- and 4-s interval of bioluminescence flash, respectively. In addition, an intermediate-flash type is found on the boundary between these two regions. 3. The differences in the responses of the males of four field populations to different intervals of artificial flashes were examined. 4. The results revealed that in the Aomori and Sendai populations (slow-flash type), a significantly larger number of males approached the 4- and 5-s flash intervals than approached the 2- and 3-s intervals of artificial flashes. On the other hand, in the Ohtsu population (fast-flash type), a significantly larger number of males approached the 2- and 3-s flash intervals than the 4- and 5-s intervals of artificial flashes. The Inuyama population (intermediate-flash type) did not show any particular preferences to flash intervals. 5. This study shows that in firefly populations, geographic variation in flash pattern can cause some degree of pre-mating isolation between populations.

Harmonized collaborative validation of a simultaneous and multiple determination method for nivalenol, deoxynivalenol, T-2 toxin, HT-2 toxin, and zearalenone in wheat and barley by liquid chromatography tandem mass spectrometry (LC-MS/MS) was conducted by participants from 12 laboratories. The fortified samples of wheat and barley at three different levels and one naturally contaminated wheat sample were extracted, consecutively purified through a Presep C18 (ODS) solid phase extraction column and a Bond Elut Mycotoxin multifunctional column, and were analyzed by LC-MS/MS. The employment of internal standards (verrucarol and zearalanone) was apparently effective to ensure repeatability and reproducibility with sufficient recovery of each mycotoxin. This is the first report of the harmonized collaborative validation study of a simultaneous and multiple determination method for both type A and B trichothecenes along with zearalenone by LC-MS/MS. The validated method should be practical for monitoring of the major Fusarium mycotoxins contained in wheat and barley.

A novel cyanobacterial vector, pTT201, containing the bar gene encoding resistance to herbicides, bialaphos and phosphinothricin, was constructed. In Synechococcus sp. strain PCC7942-SPc, the bar gene was successfully expressed. Plasmid pTT201 increased a minimum inhibitory concentration for bialaphos 16-fold over Synechococcus sp. strain PCC7942-SPc without pTT201. The combination of the bialaphos as a selective agent and the transformation by bar gene serves as a photostable selection system for Synechococcus.

An analytical method was developed for the identification and quantification of 15 mycotoxins (patulin, nivalenol, deoxynivalenol, aflatoxin B(1), B(2), G(1), G(2), M(1), T-2 toxin, HT-2 toxin, zearalenone, fumonisin B(1), B(2), B(3), and ochratoxin A) in beer-based drinks (beer, low-malt beer, new genre, and nonalcoholic) by a modified QuEChERS method and an ultra-high-performance liquid chromatography coupled with tandem mass spectrometry (UHPLC/MS/MS). Mycotoxins were extracted from samples using acetonitrile with sodium chloride, anhydrous magnesium sulfate, and sodium citrate, and were then purified with a solid phase extraction (SPE) cartridge including C18. The UHPLC conditions were also examined to establish its optimal conditions for separation. Fifteen mycotoxins were separated in a total of 6.5 min, and were quantified in the optimal mobile phase conditions. Determinations performed using this method produced high correlation coefficients of 15 mycotoxins (R0.99) and recovery rates ranging from 70.3 to 110.7% with good repeatability (relative standard deviation RSD14.6%). Further, 24 commercial beer-based drinks in Japan were analyzed using this method, and nivalenol, deoxynivalenol, and fumonisins were detected in several samples, but always under the limit of quantification (5 ng/mL). These results suggest that the health risk to consumers from beer-based drinks in Japan is relatively low.

To achieve reliable transmission of detonation wave to a pulse detonation engine (PDE) combustor, authors have proposed a PDE initiator, which consists of a predetonator and a reflector. A detonation wave propagates around the reflector changing its shape through three transition processes; from planer to cylindrical, toroidal, and planar again. Our previous study revealed that the transition to the cylindrical detonation wave upstream of the board plays a significant role in detonating hydrogen-air mixture in a 100-mm-diam-combustor. A self-sustainable condition of the cylindrical detonation wave is severe when the radius of the wave front is small. In cases using hydrogen-oxygen mixture as driver gas for the 100-mm-diam-combustor, we had to fulfill with driver gas entire upstream of the board at the critical condition for the transition to the cylindrical wave. On the other hand, curvature of the cylindrical detonation wave front becomes smaller with increasing radius of the front, so the self-sustainable condition of the cylindrical wave must be mitigated for a large bore combustor. In this study, we investigated the necessary filling diameter of the driver gas to detonate hydrogen-air cylindrical detonation by using a 500-mm-diam-cylindrical-combustor.