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Incidents of food poisoning associated with tetrodotoxin (TTX) contamination occur every year throughout Japan. Here, we determined TTX levels in leftover foods and serum and urine samples from eight food poisoning incidents associated with TTX contamination in Nagasaki, Japan, from 2011 to 2017.Seven food samples associated with four of these food poisoning incidents were classified as weakly toxic (four samples), moderate-to-strongly toxic (two samples), and strongly toxic (one sample).In comparison with previous reports, TTX was detected at harmful levels in the urine samples, but the grade of poisoning symptoms varied.The patients' time to maximum serum TTX levels (T

The low pressure arc discharge was applied to make rough the inner surface of the aluminum cylindrical tube under the following experimental conditions: arc current: 40–140 A, initial pressure: 50, 100, 200 mTorr, applied magnetic field: 0–2.5 mT. The influence of these parameters on discharge behavior, cathode erosion rate, and cathode surface roughness were investigated and discussed.

Fullerenes were synthesized by pulse arc discharge of 50 Hz-10 kHz, 150 A-500 A with graphite electrode and He ambient (about 80 Torr). Fullerene productivity was evaluated with colorimetry by toluene dissolution and with TOF-MS analysis. As a result, fullerene yield achieved a maximum at 500 Hz, 200 A, and content rate of higher order fullerenes increased with higher frequency. In addition, correlation of each fullerene was evaluated by statistical processing from TOF-MS spectra and the fullerene formation mechanism was examined.

Systemic acquired resistance (SAR) is one of the intriguing issues for studying the mechanism in signal transduction system in a whole plant. We found that SAR and increase of an antifungal compound were induced rapidly and transiently in barley (Hordeum vulgare L. cv. Goseshikoku) by mechanical and biological stresses. One of the major antifungal compounds was identified as an indole alkaloid, gramine (N,N-dimethyl-3-aminomethylindole), by mass spectrum and NMR analyses. Gramine is well known as a constitutive compound of barley, but it increased significantly in the primary and secondary leaves of barley seedlings within 12 h after pruning or inoculating with the powdery mildew fungi of barley (Blumeria graminis f.sp. hordei )a nd wheat (B. graminis f.sp. tritici). However, in the leaf detached from unwounded seedlings or in the leaf inoculated with the barley powdery mildew fungus, gramine did not increase at all. In the water droplets contacted with barley leaves, the amount of leaked gramine increased dependently upon the time after the seedling was injured mechanically. We also found a tight correlation between gramine increase and enhancement of resistance to the barley powdery mildew fungus in barley leaves treated with an endogenous elicitor. Furthermore, such a systemic resistance was not observed in a barley cultivar Morex that lacks the biosynthetic pathway of gramine. From these results, we conclude that gramine is the excellent marker in rapid and transient systemic acquired resistance in barley.

An electron gun with a very simple structure is described as being suitable for the energy range from 2 to 10 keV or more. The gun consists of a concave cold cathode and an anode with an extraction orifice, which are maintenance-free. Helium or hydrogen gas is filled with low pressure for operation in a condition called “obstructed discharge (OD)”. The concave structure of the cathode converges the electron beam well. The well-focussed electron beams are demonstrated by a shining spot on a thin plate, the current density is measured by a Faraday cup, and the energy deposit profile by a micro-calorimeter probe. The energy spectrum of electron the beam obtained was measured by an electrostatic analyzer of 90° deflection type to be sharply monochromatic with the energy of discharge voltage. This is owing to little interaction of electrons from the cathode with neutral gas. This fact requires that the discharge must be explained by mechanisms other than the well-known Townsend's theory for sustaining. It is proposed that the fast neutrals produced through charge exchange between the neutral gas and the ions accelerated toward the cathode play an essential role in the discharge-sustaining mechanism. This model is supported by a numerical calculation under several assumptions and is proved by comparison with experimental results.

A description is given of experimental results on stationary plasmas produced by 430 MHz electron cyclotron heating (ECH) in a linear multipole (hexadecapole). A uniform and stable plasma was produced with 200 W rf power in the magnetic-field-free central region over a large area (20 cm in diameter) and with an electron density of up to 1.5×1011 cm−3. This corresponds to more than 60 times the cutoff density for rf power at a frequency of 430 MHz. A silicon substrate was inserted into the midplane perpendicular to the axis. The depletion in electron density due to the insertion was small and radial uniformity was well maintained. The changes in field-free zone area and current density required to produce a stable confinement magnetic field with strong enough intensity for ECH application are described for the case when the number of current rods on a constant circumference is increased. It is concluded that in principle the uniform plasma area can be widened without limit by increasing the pole number whi...

2H NMR analysis of deuterolyzed products from cis- and trans-1,2-epoxy-4-t-butylcyclohexane indicated that the cleavage of the oxirane C–O bond proceeds with inversion of configuration over noble metal catalysts except for Ru, while with retention over Co. Both retention and inversion competitively occurs over Ni and Ru.

A high-voltage glow discharge — operated at several thousand Volts — is described by a hybrid model in which we apply kinetic simulation for the fast electrons and fast heavy particles (He þ ions and neutral atoms). In the model we take into account the increase of the gas temperature, and calculate the apparent secondary electron yield at the cathode from the fluxenergy distributions of heavy particles. The results of the simulations show that electron production at the cathode is dominated by the impact of fast neutral atoms (ejecting � 75% of the primary electrons) and that ionization of the gas atoms by fast heavy particles contributes significantly to the ionization balance of the discharge. A fair agreement is obtained between measured and calculated electrical characteristics and potential distributions, and the calculations confirm the existence of the high-energy electron beam observed experimentally. [DOI: 10.1143/JJAP.42.3633]