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Purpose: This study investigated pre-evacuation times and evacuation behaviors of vulnerable people during the 2018 flooding in Shimobara, Okayama, Japan, and the flood-triggered factory explosion, a natural hazard-triggered technological accident known as a natural-hazard-triggered technological accidents (Natech). This study examined factors that affected evacuation decisions and pre-evacuation time, estimated the evacuation time in case of no explosion and identified community disaster prevention organization response efforts for vulnerable people. Design/methodology/approach: Interviews with all 18 vulnerable people who experienced the event were conducted. Multiple regression analysis was used to examine the effect of six factors on evacuation time and reasons for delayed evacuation. Findings: Factors affecting evacuation decisions included the sound of the explosion, followed by recommendations from relatives and the community disaster prevention organization. Explosion-related injuries delayed early evacuation, but experience of previous disasters and damage had a positive effect on early evacuation. The explosion sound accelerated evacuation of non-injured people; however, explosion-related injuries significantly delayed evacuation of injured individuals. The Shimobara community disaster prevention organization’s disaster response included a vulnerable people registry, visits to all local households and a multilayered approach that enabled monitoring of all households. Originality/value: This is the first study to examine the evacuation behavior of vulnerable people and community responses during a Natech event.

In order to establish an analysis method useful for improving the performance of redox flow batteries (RFBs), electrochemical characterization based on potential control was performed on vanadium electrolyte for three different types of carbon felt electrodes. From the current (I) - potential (E) curve, differences of redox potential of vanadyl ions were observed among three electrodes. Furthermore, when comparing the quantity of electricity (Q) - potential (E) curves, a large difference was clearly observed in the reactivity with vanadyl ions. Scanning Electron Microscopy (SEM) observation and X-ray photoelectron spectroscopy (XPS) measurements showed that the defect structure of the carbon electrode and the oxygen content contained in the electrode are significantly related to the reactivity with vanadyl ions.

Suitable electrolytes and electrode materials for redox flow batteries are evaluated by using voltage step coulometry. This method is very simple and provides primary and fundamental information about electrode and electrolyte materials for use in the construction of redox flow batteries. We selected three typical carbon electrodes made of widely used and commercially available carbon fiber materials and three different types of electrolytes, namely vanadium redox solution, organic redox aqueous solution, which is currently attracting the most attention, and a new redox solution (Ti-Mn system) that was reported very recently.

To measure the interactions of diacylglycerol acyltransferase (DGAT) by surface plasmon resonance (SPR), we immobilized Saccharomyces cerevisiaeDGAT2 encoded by DGA1on a BIACORE sensor chip surface. We used N-terminally truncated Dga1p with a FLAG tag at the C-terminus, which was purified to apparent homogeneity, maintaining significant DGAT activity (Kamisaka et al., Appl. Microbiol. Biotechnol., 88, 105–115 (2010)). Truncated Dga1p with a FLAG tag was immobilized with an anti-FLAG antibody that had been coupled with an L1 chip surface consisting of a carboxymethyl dextran matrix with additional hydrophobic alkane groups. The Dga1p-immobilized chip surface was analyzed for interactions of Dga1p with oleoyl-CoA, its substrate, and anti-Dga1p IgG, its interacting protein, by SPR. The binding of these analytes with the Dga1p-immobilized chip surface was specific, because butyryl-CoA, which cannot be used as a substrate for DGAT, and anti-glyceraldehyde-3-phosphate dehydrogenase IgG, did not induce any signals on SPR. Furthermore, injection of organic compounds such as xanthohumol, a DGAT inhibitor, into the Dga1p-immobilized chip surface induced significant SPR signals, probably due to interaction with DGAT. Another DGAT inhibitor, piperine, did not induce SPR signals on application, but induced them due to piperine on application together with oleoyl-CoA, in which piperine can be incorporated into the micelles of oleoyl-CoA. The results indicate that the Dga1p-immobilized L1 chip surface recognized DGAT inhibitors. Taking all this together, SPR measurement using the Dga1p-immobilized L1 chip surface provided a useful system to elucidate the structure-function relationships of DGAT and screen DGAT inhibitors.

An on-chip enzyme-linked immunosorbent assay combined with an electrochemical detection method (EC-ELISA) was employed to detect a leptin, one of the most important adipose derived hormones, using gold electrodes modified with a tri(ethylene glycol) terminated short alkanethiol (TEGCnSH, Cn = (CH2)n, n= 2, 4, 6, and 8) monolayer. These TEGCnSH monolayers on gold electrodes can suppress non-specific protein adsorption without affecting the electrochemical activity required for detecting p-aminophenol (PAP), which is an alkaline phosphatase (ALP) product. We measured leptin with a highly sensitive detection range (100 pg mL−1to 10 ng mL−1level) and with the desired detection limit (13.6 pg mL−1) by using electrochemical detection. For detecting leptin, the EC-ELISA method using TEGC4SH modified gold electrode with a poly(dimethylsiloxane) based microchannel was superior to the conventional ELISA method. With the EC-ELISA method, we were able to measure leptin with a satisfactory detection range and a pg level detection limit within 30 min, which is a much lower detection level than that obtained with conventional plate based ELISA.

No Abstract

Gezielte Mutationender Oberflächenschleife von Halogenalkan‐Dehalogenasen haben Auswirkungen auf die Enantiodiskriminierung. Die Temperaturabhängigkeit der Enantioselektivität (siehe lnE‐1/T‐Kurve) von β‐Bromalkanen kehrt sich bei einer Deletion der Oberflächenschleife um (rote Datenpunkte), was bei Einführung einer zusätzlichen Einzelpunktmutation wieder rückgängig gemacht wird; bei α‐Bromestern findet keine Änderung statt.

Tri(ethylene glycol) terminated short alkylchain thiols (TEGCnSHs) offer good potential for constructing ultra-thin protein-resistant monolayers because they have an alkylchain for forming a densely packed monolayer and a flexible-hydrophilic oligo ethylene glycol arm for avoiding non-specific adsorption. Hybrid monolayers consisting of TEGCnSH and a maltoside ligand (MalC12SH, for capturing lectin) were effective in detecting concanavalin A (Con A). This hybrid monolayer was more suitable for Con A detection than that modified with 100% ligands in terms of the detection limit and time. The anti-fouling properties, packing densities, interaction and homogeneity of TEGCnSH monolayers were confirmed in detail by surface plasmon resonance (SPR) measurements and electrochemical methods. SPR measurements revealed their excellent repellency to proteins and peptides of various sizes (MW400 – 104000). The electrochemical results indicated that the lower defects in the TEGCnSH monolayers suppressed the permeation of small peptides. The stability, homogeneity and packing density of the TEGCnSH monolayers were gradually improved as their alkylchain length increased.

The electrochemical detection of 6‐mercaputopurine (6‐MP), which is one of the most well‐known drugs of antimetabolites, and its analogues was studied. The presented method is based on chemisorption (accumulation)/desorption processes of drugs onto/from the Au electrode surface. Using this method, we succeeded in detecting 6‐MP even in very diluted solution (concentration of 6‐MP: 1×10−8M). The lower detection limit of 6‐MP was considerably improved compared with the previous HPLC studies by using our proposed system. Desorptive potentials of 6‐MP‐metabolites and its analogues were different from those of 6‐MP. This provides the possibility of simultaneous detection of 6‐MP and its typical metabolites.

Adsorption processes and electrochemical properties of benzeneselenol and benzenethiol on gold electrodes were investigated by surface-enhanced IR absorption spectroscopy SEIRAS and electrochemical measurements. From the IR spectroscopic measurements, it was confirmed that benzeneselenol molecules adsorbed on the gold surface as benzeneselenolate–Au. SEIRAS measurements revealed that benzeneselenol took a much longer time to adsorb on a gold surface than benzenethiol. Electrochemical reductive desorption of these monolayers in alkaline solution proved that benzeneselenoate chemisorbed on gold surfaces were more stable compared to benzenethiolate, since the reduction peak potential of benzeneselenolate shifted to more than 200 mV negative potential than that of benzenethiolate. The total amounts of adsorbed benzeneselenol molecules were smaller than the case of benzenethiol.

In situ scanning tunneling microscopy (STM) and cyclic voltammetry were employed to investigate self-assembled monolayers of 3-mercaptopropionic acid (MPA) on Au(111) in perchloric acid solutions. In situ STM revealed that the MPA monolayer was composed of translationally and rotationally ordered MPA domains, and some disordered portions also coexisted on the surface, particularly near the etch pits. The ordered monolayer exhibited a molecularly ordered (3×3) structure, where three MPA molecules in triangular positions stand fairly close together due to intermolecular hydrogen bonding. Two distinctly different phase boundaries were found between the ordered (3×3) domains, and high-resolution STM images disclosed the molecular arrangement of the MPA monolayers. The MPA monolayer desorbed at negative potentials, causing transformation of the surface into the Au(111)-(√3×23) reconstruction. The in situ STM successfully elucidated the interfacial structure and phase boundary of the MPA monolayers on Au(111) under electrochemical conditions.

Electrochemical superoxide dismutase (SOD) sensors were prepared by using cytochrome c‐immobilized monolayers and xanthine oxidase (XOD)/cytochrome c‐bilayers. Cytochrome c was covalently immobilized on mercaptopropionic acid‐containing self‐assembled monolayers (SAMs) on gold. The rate of cytochrome c‐catalyzed oxidation of superoxide anion was affected by the structure of the SAM: the use of a mercaptopropionic acid/mercaptopropanol mixed‐SAM gave higher reaction rate than the case of pure mercaptopropionic acid SAM. For the highly‐sensitive detection of the superoxide anion generated by xanthine‐XOD enzymatic reaction, the bilayer system was suitable, as compared with the monolayer system: superoxide anion was generated near the gold electrode surface in the case of the bilayer system, which resulted in much larger anodic current response. Further, the use of a poly‐L‐lysine/polystyrenesulfonate‐complex as the support for XOD enabled the detection of the superoxide anion‐generation process in the presence of L‐ascorbic acid up to 200 µM. Although L‐ascorbic acid could scavenge superoxide anion, it cannot be permeated into the polyion complex layer. By using the bilayer‐based electrode, the activity of SOD could be measured in the presence of L‐ascorbic acid.

The adsorption properties, amount and specific activity of lipase D from Rhizopus delemar were investigated by employing a gold substrate modified with seven kinds of thiol monolayer. Quartz crystal microbalance measurements revealed that the amount of the enzyme adsorbed to the hydrophobic monolayers (e.g. benzenethiol) was much higher than that to the hydrophilic monolayers (e.g. 3-mercaptopropanoic acid). In contrast, lipase D adsorbed to the hydrophilic, 2-amino-1-ethanethiol monolayer showed the highest specific activity, the value being 300-fold higher than for the same enzyme dissolved in an aqueous medium.

The potential dependent structure change and mass transport at an 11-ferrocenyl-1-undecanethiol (FcC11SH) self-assembled monolayer on a gold electrode with various coverages were investigated by simultaneous Fourier transform infrared reflection absorption spectroscopy (IRRAS) and electrochemical quartz crystal microbalance (EQCM) measurements in 0.1 M HClO4 solution. As soon as the terminal ferrocene group was oxidized to a ferricenium cation (Fc+), a number of upward and downward IRRAS bands were observed and the surface mass was increased. The intensity of the IRRAS bands corresponded well with the mass change. This behavior is attributed to the redox reaction induced orientation change in the FcC11SH monolayer and ion pair formation between the Fc+ cation and the perchlorate anion in solution. The FcC11SH monolayer with a lower coverage was less stable and was decomposed at a less positive potential than that with a high coverage. Models are proposed to explain the coverage dependent behavior of the FcC11SH monolayer induced by the redox reaction of the terminal ferrocene moiety.

In order to clarify the electrochemical response of cytochrome cat the gold electrode modified with mixed monolayers of carboxylic acid terminated alkanethiol (promoter molecule) and n‐alkanethiol (barrier molecule), electrochemical and electrochemical quartz crystal microbalance (EQCM) measurements were carried out during the reductive desorption of the mixed monolayer of 3‐mercaptopropionic acid and 1‐octadecanethiol (C18SH) in alkaline solution. The ratio of mercaptopropionic acid in the mixed monolayer was found to be smaller than that in the modifying solution, showing that C18SH adsorbed more preferentially than mercaptopropionic acid. The peak potentials for the reductive desorption of mercaptopropionic acid became more negative upon increasing the C18SH content in the monolayer. This means mercaptopropionic acid and C18SH did not form patched domains but were mixed well with each other. The mercaptopropionic acid molecules in a well‐mixed monolayer should be stabilized through the affinity between the mercaptopropionic acid and C18SH and becomes difficult to be desorbed from the electrode.

The electron-exchange reaction between the ferrocenyl group of self-assembled monolayers of 11-ferrocenyl-1-undecanethiol on gold electrodes and Fe(III) species in solution is studied. The monolayer acts as an effective electron-transfer mediator for the reduction of Fe(ClO4)3but inhibits the oxidation of Fe(ClO4)2in HClO4and NaClO4solution. This behavior is also observed in HClO4solutions containing FeIII(edta) but only when the concentration of HClO4is higher than 0.5 M. Absorption spectra and spectroelectrochemical and electrochemical measurements show that FeIII(edta) dissociates in highly acidic solutions and generates Fe3+aq, which acts as an electron-accepting species.

An amperometric l-glutamate-sensing electrode was prepared by immobilizing glutamate oxidase (GlOx) on a polyion complex layer-modified electrode. First, a monolayer of 3-mercaptopropionic acid was made on the surface of a gold electrode by immersing it in an ethanol solution containing the modifier. Next, aqueous solutions of poly-l-lysine and poly(4-styrenesulfonate) were successively placed on the electrode surface and allowed to dry. Finally, a GlOx layer was formed on the poly-l-lysine/poly(4-styrenesulfonate)-complex layer by crosslinking the enzyme by the addition of a glutaraldehyde solution. The use of thin bilayer system with the inner, polyion complex membrane, which showed permselectivity based on the solute size with the molecular cut-off of ≈100, brought high performance characteristics to the l-glutamate-sensing electrode; it showed high sensitivity (detection limit, 20 nM), rapid response (100% response time, 3 s), low interferential level (the ratio of response for l-ascorbic acid to that for the same concentration of l-glutamic acid, 8×10−2), and high stability (usable for more than a month). The bilayer-based electrode was useful for the rapid measurement of glutamate–oxaloacetate transaminase (GOT) and glutamate–pyruvate transaminase (GPT) in serum sample: each transaminase (0.2–1000 U l−1) could be determined within 10 s.

The effects of self-assembly time on the order and orientation of 11-ferrocenyl-1-undecanethiol (FcC11SH) molecular layers on gold were studied with polarization modulation Fourier transform infrared spectroscopy. A comparison between the intensity of the asymmetric methylene stretching mode of a 1-octadecanethiol monolayer and that of the FcC11SH molecular layer confirmed that the FcC11SH molecules formed a self-assembled monolayer on the gold surface. The conformational order of the monolayer increased with longer self-assembly time as evidenced by a decrease in the vibrational frequencies of the methylene stretching modes and a decrease in the full width at half maximum of these bands. The peak area of the asymmetric methylene stretch also decreased with longer self-assembly time, implying that the FcC11SH molecules stood more erect with respect to the gold surface as the monolayer self-assembled.

Self-assembled monolayers of 11-ferrocenyl-1-undecanethiol on Pt have been characterized with an electrochemical quartz crystal microbalance and X-ray photoelectron spectroscopy. Well-packed monolayers were defect-free, but less compact than on Au. The high affinity of Pt for oxygen made the monolayer relatively unstable compared with monolayers on Au.

In order to establish an analysis method useful for improving the performance of redox flow batteries (RFBs), electrochemical characterization based on potential control was performed on vanadium electrolyte for three different types of carbon felt electrodes. From the current (I) – potential (E) curve, differences of redox potential of vanadyl ions were observed among three electrodes. Furthermore, when comparing the quantity of electricity (Q) – potential (E) curves, a large difference was clearly observed in the reactivity with vanadyl ions. Scanning Electron Microscopy (SEM) observation and X-ray photoelectron spectroscopy (XPS) measurements showed that the defect structure of the carbon electrode and the oxygen content contained in the electrode are significantly related to the reactivity with vanadyl ions.

Suitable electrolytes and electrode materials for redox flow batteries are evaluated by using voltage step coulometry. This method is very simple and provides primary and fundamental information about electrode and electrolyte materials for use in the construction of redox flow batteries. We selected three typical carbon electrodes made of widely used and commercially available carbon fiber materials and three different types of electrolytes, namely vanadium redox solution, organic redox aqueous solution, which is currently attracting the most attention, and a new redox solution (Ti-Mn system) that was reported very recently.

Electrochemical properties for two kinds of carbon felt electrodes were evaluated using single filament electrodes. Results of cyclic voltammogram (CV) measurements for both carbon fiber electrodes showed wide potential windows (-1.0 ~ +1.9 V vs. Ag/AgCl). In the case of felt sample 1 (thin electrode), which was actually used in the vanadium-based RFB, dispersion of oxidation and reduction peaks was smaller than that of sample 2 (thick electrode, general carbon felt electrode). Redox responses were also measured in the vanadium electrolyte. Sample 1 electrode showed low dispersion in redox responses and had suitable electrochemical property for vanadium-based RFBs.

The chemisorption/reductive desorption-process of a thiol compound on a silver electrode was applied to the highly sensitive determination of a thiol-producing enzyme, acetylcholinesterase.

Self-assembled monolayer of ferrocenylundecanethiol on gold electrode catalyzed electro-oxidative chemiluminescence from a luminol/hydrogen peroxide system.

Scanning tunneling microscopy (STM) of self-assembled monolayers (SAMs) on Au(111) prepared from mixtures of bis(4-pyridyl) disulfide and 1-decanethiol revealed that patched domains of each organosulfur compound were formed.