Heat-killed Enterococcus faecalis FK-23 strain （heat-killed FK-23） was administered orally to rainbow trout Oncorhynchus mykiss at 24,120, and 600 mg/kg body weight/day for up to 6 weeks to investigate its effects on the biological defense activity and the physiological indices of the fish. Administration of heat-killed FK-23 did not affect the appearance, swimming performance, feeding behavior, growth rate, number of blood cells or the lysozyme activity of skin mucus, but did increase significantly the phagocytic activity of granulocytes and monocytes. The NBT reduction activity of granulocytes was significantly higher at week 4 of the group whose dosage was 120 mg/kg body weight/day. Plasma protein, glucose and ALT levels did not change, but diminished plasma total lipids and enhanced antioxidant activity of plasma were found at the 600 mg/kg body weight/day dosage at week 4. Aerobic and facultative anaerobic bacteria increased in the FK-120 group. There was no difference in the composition of aerobic and facultative anaerobic bacteria in the intestine of fish at the same time. Bacteroides spp., an obligatory anaerobe, increased in the FK-600 group. These results indicate that 1） the oral administration of heat-killed FK-23 enhanced the innate immune activity of fish, mainly through activation of phagocytosis of granulocytes and monocytes, 2） the intake is about 120 mg/kg body weight/day, which is necessary to maintain high biological defense in rainbow trout, 3） the intake at 600 mg/kg body weight/day may be effective for improving lipid metabolism and enhancing antioxidant activity in the fish.

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We examined the effect of infrared light emission （central wavelength of 940 nm） on the settlement of cypris larvae on the surface of a flat plate reached by light. Only 8.5 ± 3.9 % (n=3) of individuals settled on the surface. The radiant intensity at the center and the edge 5 cm from the center were estimated to be 58.3 and 34.2 W m⁻², respectively. Those results indicate that cypris larvae can move spontaneously to avoid infrared light that reaches down with a radiant intensity of approximately more than 34.2 W m⁻².

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Capillary zone electrophoresis （CZE） is proposed for the determination of inorganic anions and cations in seawater and salts. However, CZE is unfamiliar to most people as an analytical method for ionic substances. As described in this short paper, a simple experiment was used to allow people to feel much closer to CZE. The specific purpose is to show electroosmosis and electrophoresis visually. They form the basis of CZE. Materials used for experimentation are pottery clay in a plastic box, glass tubes, leads, dry batteries, and tap water, all of which are readily available. Two important phenomena were observed during a short time.

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Recently, nitrogen cycling has become an issue, and electrodialysis as a membrane separation technique has been considered as a method to recover ammonium nitrogen (NH₄⁺) from wastewater. In this study, we compared the concentration factor and recovery rate of NH₄⁺ between standard membranes and monovalent selective membranes in multistage continuous flow electrodialysis using a model industrial wastewater containing three cations, NH₄⁺, Na⁺, and Ca²⁺. By using the monovalent selective membranes, the concentration factor and the recovery rate were 10 and 96％, respectively, which values were higher than those obtained using the standard membranes. This was due to the fact that the monovalent selective membranes suppressed the transport of coexisting Ca²⁺ in wastewater.

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To quantify inorganic phosphate (PO₄^3-) in salts for this study, we used transient isotachophoresis (tITP) / capillary zone electrophoresis (CZE) with indirect UV detection. As a slight modification of a PO₄^3- detection method developed earlier for seawater, a terminating ion (TI) was intentionally not introduced into the background electrolyte (BGE) in the capillary. Instead, a UV-absorbing compound in the BGE served as the TI: 2,6-pyridinedicarboxylic acid (PDC). Furthermore, instead of 200 nm, a 273 nm detection wavelength was used because of its better signal-to-noise (S/N) ratio. The relative standard deviation (RSD) values (n ＝ 4) for peak area, peak height, and migration time of PO₄^3- were, respectively, 3.8 ％, 3.6 ％, and 0.53 ％. The limit of detection (LOD, S/N ratio ＝ 3) and limit of quantification (LOQ, S/N ratio ＝ 10) for PO₄^3- were, respectively, 0.013 and 0.044 mg/L (as P (PO₄^3--P)). These LOD and LOQ values correspond to 0.40 and 1.3 mg/kg (per kilogram of salt). After applying the proposed method to quantify PO₄^3- in various salt samples, including seaweed salt, the obtained CZE results showed agreement with those obtained using molybdenum blue absorptiometry (conventional method). These findings demonstrate this method as valid for detecting PO₄^3- in salts.

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The product, including layered double hydroxide with anion removal, can be synthesized in bittern by the addition of aluminum dross fused with sodium hydroxide. Products such as hydrotalcite, gibbsite, and calcite can be synthesized from bitterns with fused aluminum dross and have the ability to remove phosphate ions. During the synthesis, hydrogen gas was generated, and the amount of hydrogen gas increased with increasing the addition of the dross.

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In this study, we compared the power generation performance of reverse electrodialysis (RED) stacks using flat ion exchange membranes (IEMs) and novel profiled (PF) IEMs with a constant thickness and an uneven structure. Compared to the flat IEMs, the PF IEMs showed a 31 ％ decrease in the internal resistance of the RED stack and a 40 ％ increase in the maximum power density, with a value of 1.4 W/m².

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