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Perchlorate concentrations in raw and tap water in Osaka, Japan, were determined by IC-MS/MS. The concentrations of perchlorate in raw water and tap water were in the ranges from

Polyphosphate is ubiquitous among living organisms and has a variety of biochemical functions. Arbuscular mycorrhizal fungi have been known to accumulate polyphosphate as a key compound for their function. However, an enzymatic assay using polyphosphate kinase (PPK) reverse reaction, in which polyphosphate is converted to adenosine triphosphate (ATP) and quantified by luciferase assay, failed to detect accumulation of polyphosphate in some mycorrhizal root. When yeast exopolyphosphatase (PPX) was applied to these samples, a much higher polyphosphate level was detected than when the PPK assay was applied. Detailed analysis of substrate chain length specificity of these methods using polyphosphate chain length standards revealed that the PPX method was the most appropriate to detect short-chain polyphosphate. The average chain length of the shortest polyphosphate fraction that could be quantified with more than 50% efficiency was 3 for the PPX method and 38 for the PPK method. It was also suggested that the ratio of the PPK value to the PPX value may be useful as a simple and relative index to compare polyphosphate chain length distribution in different samples.

This paper presents the first performance results of the ALICE TPC Readout Control Unit 2 (RCU2). With the upgraded hardware typology and the new readout scheme in FPGA design, the RCU2 is designed to achieve twice the readout speed of the present Readout Control Unit. Design choices such as using the flash-based Microsemi Smartfusion2 FPGA and applying mitigation techniques in interfaces and FPGA design ensure a high degree of radiation tolerance. This paper presents the system level irradiation test results as well as the first commissioning results of the RCU2. Furthermore, it will be concluded with a discussion of the planned updates in firmware. publishedVersion

This paper describes the development of a practical method for the analysis of phosphorus compounds with a focus on sugar phosphates from the model higher plant Arabidopsis thaliana by ion chromatography coupled to electrospray ionization tandem mass spectrometry (IC-ESI-MS-MS). After the analytical separation, the potassium hydroxide eluent was converted to water with an anion suppressor allowing the effluent from the IC to be connected to the mass spectrometer directly. In the optimized method, 17 phosphorous compounds (adenosine diphosphate (ADP), fructose 1,6-bisphosphate, fructose 2,6-bisphosphate, fructose 6-phosphate, galactose 1-phosphate, glucose 1-phosphate, glucose 1,6-bisphosphate, glucose 6-phosphate, mannose 6-phosphate, phosphoenol pyrvate, 3-phosphoglyceric acid, ribulose 1,5-bisphosphate, ribulose 5-phosphate, ribose 5-phosphate, sucrose 6-phosophate and uridine 5'-diphosphate-glucose (UDPG)) were determined. The linearity of response for these phosphorous compounds over the concentration range of 0 and 10 microM was better than 0.9993 in all cases. The minimum detection limit was between 0.01 and 2.50 microM for a 25 microL injection, and recovery rates for standard addition to the sample were within the range from 93% to 110%.

We have established a new system for studying phytic acid, myo-inositol hexakisphosphate (InsP6) synthesis in suspension-cultured cells of Catharanthus. InsP6 and other intermediates of myo-inositol (Ins) phosphate metabolism were measured using an ion chromatography method. The detection limit for InsP6 was less than 50 nm, which was sufficient to analyze Ins phosphates in living cells. Synthesis of Ins phosphates was induced by incubation in high inorganic phosphate medium. InsP6 was mainly accumulated in vacuoles and was enhanced when cells were grown in high concentration of inorganic phosphates with the cations K+, Ca2+, or Zn2+. However, there was a strong tendency for InsP6 to accumulate in the vacuole in the presence of Ca2+ and in nonvacuolar compartments when supplied with Zn2+, possibly due to precipitation of InsP6 with Zn2+ in the cytosol. A vesicle transport inhibitor, brefeldin A, stimulated InsP6 accumulation. The amounts of both Ins(3)P1myo-inositol monophosphate synthase, a key enzyme for InsP6 synthesis, and Ins(1,4,5)P3 kinase were unrelated to the level of accumulation of InsP6. The mechanisms for InsP6 synthesis and localization into vacuoles in plant cells are discussed.

Polyphosphate is ubiquitous and has a variety of biochemical functions. Among polyphosphate quantification methods, an enzymatic assay using Escherichia coli polyphosphate kinase (PPK), in which polyphosphate is converted to adenosine 5'-triphosphate and quantified by luciferase assay, is the most specific and most sensitive. However, chain-length specificity of the assay has not been analyzed in detail so far. Ion chromatography equipped with an on-line hydroxide eluent generator enabled us to analyze polyphosphate up to 50 inorganic phosphate (P(i)) residues, and we employed this method to investigate the chain-length specificity of PPK in this study. Several fractions of short-chain polyphosphate were prepared by electrophoresis, and the chain-length distribution was analyzed before and after 1-6 h PPK reaction by ion chromatography. Polyphosphates longer than 23 P(i) residues were processed by PPK completely after 1 h incubation, but complete processing of those between 11 and 22 P(i) residues required 6h incubation. Limited processing of polyphosphates of 10 P(i) residues or shorter were observed even after 6h incubation. Metachromasy of Toluidine blue O, an alternative method for polyphosphate quantification, showed broader chain-length specificity although it was not as sensitive as the enzymatic assay. Combination of these two methods would be practically applicable to analysis of polyphosphate dynamics in living organisms.

We have developed a method for comprehensive analysis of sugar phosphates by high performance anion exchange chromatography with pulsed amperometric detection coupled with a titanium dioxide column as a trap-column to remove sample matrices. Levels of sugar phosphates and a nucleotide phosphate from Arabidopsis thaliana grown at three different inorganic phosphate (Pi) concentrations in nutrient media or from Pi-related Arabidopsis mutants were investigated. Fructose-6-P, Galactose-1-P, Glucose-1-P, Glucose-6-P and Mannose-6-P apparently increased in proportion to increases in the in vivo level of Pi in wild type plants. In contrast, levels of Sucrose-6-P and UDP-Glucose decreased as the in vivo Pi levels increased. Responses of the former sugar phosphates except Mannose-6-P to the in vivo Pi levels in shoots of the mutants were similar in the wild type plants. However, Sucrose-6-P and UDP-Glucose responded differently between the wild type and mutant plants.

An ion chromatographic method with gradient elution using an automated eluent generator was developed for the simultaneous determination of condensed phosphates (CPs) such as orthophosphate (P1), pyrophosphate (P2), polyphosphate, trimetaphosphate and phytate in food products. The linear calibration curves for P1, P2, tripolyphosphate, and tetrapolyphosphate in the range 0.5–500 μ M had a correlation factor of 0.999 or better. The precision of the method for the CP peak areas obtained with the hydroxide eluent generator was better than that obtained with potassium hydroxide eluents prepared off-line. This method was applied to the determination of CPs in food products such as ham, fish paste, and cheese extracted by trichloroacetic acid.

Three geotextile structures were constructed on the Seisho coast, Japan. The size and design of each structure were investigated using a two-dimensional wave flume. The resistances to abrasion caused by coastal sediments were estimated with a newly developed accelerated abrasion test. These field and laboratory studies showed that geotextile structures are easy to construct and durable on the gravel-mixed Japanese coast.

This paper describes the development of a practical method for the analysis of sugar phosphates from the model higher plant Arabidopsis thaliana by high-performance anion-exchange chromatography with pulsed amperometric detection (HPAEC–PAD). The extraction method of sugar phosphates from higher plants was first optimized for HPAEC–PAD analysis. In order to improve the resolution in HPAEC–PAD, a column packed with titanium dioxide resin was used. The titanium dioxide column was used as a trap-column for sugar phosphates and nucleotides, for the removal of sample matrices. Sample pretreatment was achieved in-line and automatically using a six-port valve placed after the injection valve.

To stablish the method evaluating the durability of geosynthetic structures on coast, field observations of concrete blocks and field exposure of geosynthetic test pieces were carried out on Japanese coasts. We analyzed the depths of erosion measured on coasts using multivariate statistical analysis, and investigated the effectiveness of the duration of settlement, elevation, wave conditions and size of coastal sediments on the degree of abrasion. Two types of accelerated tests for imitating gravel abrasion and a weathering test were developed, and the applicability of these tests were assessed by comparing the results to the results from field exposure tests. Based on these tests, we proposed the methods for estimating the remaining tensile strength of geosynthetic materials after settlement.