Development of a new estimation method of ingestion time to suspected food in food-poisoning outbreaks

In food-poisoning outbreaks, the ingestion time of suspect foods has been estimated using the Sartwell method (Hirayama method), the graphical method and maximum likelihood estimation. These methods are based upon the assumption that the incubation period is log-normally distributed. However, these methods may not always be valid because the bias and variability of the estimates are large. We constructed a database from 341 food-poisoning cases in the literature. Using this database, we developed a method to estimate the actual ingestion time based on the period from the ingestion time to the first outbreak, using a multiple linear regression equation. Since only 9.09% of cases showed log-normal distribution, the above three methods would not be valid in most cases. The new method was applicable in all cases. In addition, the values estimated by the new method showed higher correspondence and accuracy than the values estimated by the other methods. Therefore, we consider that the new method is superior to those methods.     

Preparation of hydrophobic electrocatalyst layer and inorganic porous electrolyte layer for water absorbing porous electrolyte electrolysis cell

A water-absorbing porous electrolyte electrolysis cell is presented consisting of a hydrophobic gas diffusion layer (GDL), a controlled-hydrophobicity electrocatalyst layer, and a hydrophilic porous electrolyte layer. The specific character of this cell is that high-pressure water is injected directly into the porous electrolyte layer and is resisted by the electrocatalyst layer and GDL, which have strong water support force. In this study, the preparation method of the electrocatalyst layer and the porous inorganic electrolyte layer, and the evaluation of water electrolysis using the prepared layers were investigated. The optimized conditions and preparation methods of each layer of the MEA (i.e. the GDL, electrocatalyst layer, electrolyte layer) were determined. The assembly method and conditions of these three layers were also determined for fabricating MEAs for water electrolysis. The evaluation of water electrolysis tests using this MEA showed that the hydrogen evolution rate obeyed Faraday's Law in the low current density region (<10 mA cm^?2).     

Reduction in Ripple Current and Self‐Inductance by Using Electromagnetic Coupling of Reactor

To produce DC current by using a multiphase reversible chopper, smoothing reactors are needed. When smoothing reactors are employed, the chopper device becomes large and heavy, especially if electromagnetic interference is avoided. The reduction in the ripple current by electromagnetic coupling contributes to making the chopper device smaller and lighter. We deduced the relationships among the ripple current amplitude, duty factor, and electromagnetic coupling coefficient. To determine the loss and gain, we introduced the ratio of the amplitude of the ripple current in each phase and in the total combined current of the multiphase chopper system to that of the ripple current in a one‐phase chopper, A_ph, A_sum, respectively. This value indicates the reduction not only in the ripple current amplitude but also in the self‐inductance. The minimum value of the above‐mentioned ratio obtained analytically is accurately determined. We derived the minimum values and obtained the range within which reduction of the ripple current amplitude for both each phase and total combined is achieved. Finally, we applied an optimal electromagnetic coupling coefficient to the design of on‐board reactors of electric railway vehicles. © 2013 Wiley Periodicals, Inc. Electr Eng Jpn, 186(2): 68–82, 2014; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.22480     

Dechlorination of 1‐chlorohexadecane and 2‐chloronaphthalene in water under sub‐ and supercritical conditions

Reactions of 1‐chlorohexadecane and 2‐chloron‐aphthalene in water under sub‐ and supercritical conditions have been investigated so as to show the possible use of water for the dechlorinations of these organic chlorides. The reactions were carried out at 275°C to 430°C in a small SUS316 batch reactor under nitrogen atmosphere at the molar organic chloride/water ratio of 1/100. Under subcritical temperatures, hydrolysis reactions occurred catalyzed by H⁺ ions, whereas under supercritical conditions hydrodechlorinations occurred too, in which hydrogens evolved by the reaction of HCI with the metal wall of the reactor participated. The hydrogenation and hydrogenolysis of the primary reaction products also occurred for 1‐chlorohexadecane under supercritical conditions. The dechlorination selectivity was nearly 100% for these organic chlorides irrespective of the reaction conditions employed.     

Construction of cardiac tissue rings using a magnetic tissue fabrication technique

Here we applied a magnetic force-based tissue engineering technique to cardiac tissue fabrication. A mixture of extracellular matrix precursor and cardiomyocytes labeled with magnetic nanoparticles was added into a well containing a central polycarbonate cylinder. With the use of a magnet, the cells were attracted to the bottom of the well and allowed to form a cell layer. During cultivation, the cell layer shrank towards the cylinder, leading to the formation of a ring-shaped tissue that possessed a multilayered cell structure and contractile properties. These results indicate that magnetic tissue fabrication is a promising approach for cardiac tissue engineering.     

THERMODYNAMIC STUDY OF M3+/H+ EXCHANGE SYSTEMS ON TITANIUM ANTIMONATE CATION EXCHANGER

ABSTRACT

Selectivity coefficients K_H ^M for trivalent metal ions / hydrogen ions (M³⁺/H⁺) exchanges on titanium antimonate cation exchanger (TiSbA) have been determined for group 13 metals (Al³⁺, Ga³⁺, and In³⁺) and rare earth metals (La³⁺, Nd³⁺, Eu³⁺, Yb³⁺, and Y³⁺) ions by batch equilibration at 30, 45, and 60 ^°c in nitric acid media. Kielland plots (logK_H ^M vs. the fractional exchange X¯_M) for these exchange systems have been analyzed and found to show a break point at X¯_M=0.005-0.01. This behavior can be interpreted assuming a two-site model. A site available at infinitesimal X¯_M value has a large steric effect. The selectivity in this site increased in the order: Al³⁺ < Ga³⁺ < In³⁺ for group 13 metal ions and Y³⁺ < Yb³⁺ < Eu³⁺ < Nd³⁺ < La³⁺ for rare earth metal ions in the X¯M<0.02 region at 30^°C. The amounts of Ga³⁺ exchanged by TiSbA increased with a rise in temperature. The selectivity of group 13 metal ions changed to: AI³⁺ < In³⁺ < Ga³⁺ at 60^°C. On the other hand, the selectivity order for rare earth metal ions was independent of temperature. The hypothetical thermodynamic data (ΔG^o _ideal, ΔH^o _ideal and ΔS^o _ideal) at 25^°C were evaluated.     

High level expression of a synthetic gene coding for IgG-binding domain B of Staphylococcal protein A

A gene coding for one of the IgG-binding domains of Staphylococcalprotein A, designated domain B, was chemically synthesized.This gene was tandemly repeated to give dimeric and tetramericdomain B genes by the use of two restriction enzymes which gaveblunt ends. The genes were highly expressed in Escherichia colito afford a large amount of dimeric and tetrameric domain Bproteins. The single domain B protein was efficiently producedas a fusion protein with a salmon growth hormone fragment. Thefusion protein was converted to monomeric domain B by cyanogenbromide cleavage. The CD spectra of the monomeric, dimeric andtetrameric domain B proteins were essentially the same as thatof native form protein A, showing that their secondary structureswere very similar. The dimeric and tetrameric domain B proteinsformed precipitates with IgG as protein A. This system permitsthe efficient production of mutated single and multiple IgG-bindingdomains which can be used to study structural changes and proteinA–immunoglobulin interactions.     

Deoxidation of molten copper with a rotating graphite cylinder

The kinetics of deoxidation of molten copper by the “vacuum-suction degassing” (VSD) method is investigated. The molten copper is deoxidized by a rotating porous graphite tube immersed in the copper bath. The inside space of the porous graphite tube is evacuated so that the CO gas formed at the graphite-metal interface is removed through the tube wall. The experimental results suggest that the mass transfer of oxygen in the metal phase controls the reaction rate. The kinetic data are arranged with a first-order rate equation. At (ppm O)≥10, the rate constant increases by decreasing the porosity of the graphite and increasing the thickness of the tube wall. This result suggests that the suction of CO gas weakens CO bubble stirring and, thereby, the mass transfer at the tube-melt interface. However, when the rate of CO suction becomes comparable to or larger than the CO gas evolution rate, the effect of CO stirring becomes negligible. This situation appears under the conditions of high porosity and large wall thickness at (ppm O) ≥ 10. At the low oxygen concentration range of (ppm O) ≤ 4, the effect of CO stirring becomes negligible, regardless of the CO suction condition, because of the considerably low CO formation rate. The achievement of deoxidation by the VSD method is evaluated in connection with the final oxygen concentration.     

Follistatin-like immunoreactivity in the cytoplasm and nucleus of spermatogenic cells in the rat

Incidence of Kawasaki disease in Japan is 10 times higher than in the United States. Approximately 10% of patients have atypical clinical presentations. Because echocardiographic or angiographic evidence of coronary artery complications is needed for diagnosis, such atypical cases often result in either delay or omission of intravenous gamma globulin therapy and higher incidence of coronary artery aneurysms than those patients with classical presentations. Despite ongoing research, no universally accepted etiologic theory exists today. Intravenous gamma globulin remains the mainstay of the acute phase treatment of Kawasaki disease. However, reported transmission of hepatitis C virus via a brand of intravenous gamm globulin leaves us with a lingering concern about the safety of this treatment. In terms of long-term follow-up, emergencence of a number of newer diagnostic modalities is promising and warrants careful evaluation. Surgical therapy for coronary artery disease needs to be approached cautiously.