The pillaring of Na-montmorillonite with cationic oligomers of hydroxyaluminum (COHA) in the presence of an aqueous solution of polyvinyl alcohol resulted in the formation of a clay having a large surface area and pore volume. The pore-size distribution determined from a N2 adsorption/desorption hysteresis was narrow and centered at about 25 Å. The peak width at half height in the distribution curve was < 5 Å. As a result of delamination, the layer structure of the prepared clay was found from X-ray powder diffraction measurements to be lost. Short-range ordering, however, still existed in this delaminated clay, because exchangeable cations in the montmorillonite completely exchanged with Al3+, a requisite step for pillaring.

The order of adding the starting materials (Na-montmorillonite, polyvinyl alcohol, and COHA) greatly affected the surface area and the pore volume of the delaminated clay. Two orders of addition (Namontmorillonite, then COHA, then polyvinyl alcohol; and COHA, then Na-montmorillonite, then polyvinyl alcohol) gave no measurable surface area and pore volume. Two other orders of addition (polyvinyl alcohol, then COHA, then Na-montmorillonite; and polyvinyl alcohol, then Na-montmorillonite, then COHA) gave surface areas of 107 and 160 m2/g and pore volumes of 0.13 and 0.29 cm3/g, respectively. The amounts of the COHA solution and polyvinyl alcohol added greatly influenced the surface area and pore volume of the delaminated clay. Both properties increased monotonically with increasing amount of added polyvinyl alcohol, and increased to a maximum and then decreased with increasing amount of added COHA solution. The maximum surface area of the prepared delaminated clay was 330 m2/g.

An experimental study is performed to investigate the effects of the extensional rheological properties of drag-reducing wormlike micellar solutions on the vortex deformation and turbulence statistics in two-dimensional (2-D) turbulent flow. A self-standing 2-D turbulent flow was used as the experimental set-up, and the flow was observed through interference pattern monitoring and particle image velocimetry. Vortex shedding and turbulence statistics in the flow were affected by the formation of wormlike micelles and were enhanced by increasing the molar ratio of the counter-ion supplier to the surfactant, ξ, or by applying extensional stresses to the solution. In the 2-D turbulent flow, extensional and shear rates were applied to the fluids around a comb of equally spaced cylinders. This induced the formation of a structure made of wormlike micelles just behind the cylinder. The flow-induced structure influenced the velocity fields around the comb and the turbulence statistics. A characteristic increase in turbulent energy was observed, which decreased slowly downstream. The results implied that the characteristic modification of the 2-D turbulent flow of the drag-reducing surfactant solution was affected by the formation and slow relaxation of the flow-induced structure. The relaxation process of the flow-induced structure made of wormlike micelles was very different from that of the polymers.

Predicting the need for hospitalisation of patients with coronavirus disease 2019 (COVID-19) is important for preventing healthcare disruptions. This observational study aimed to use the COVID-19 Registry Japan (COVIREGI-JP) to develop a simple scoring system to predict respiratory failure due to COVID-19 using only underlying diseases and symptoms. A total of 6873 patients with COVID-19 admitted to Japanese medical institutions between 1 June 2020 and 2 December 2020 were included and divided into derivation and validation cohorts according to the date of admission. We used multivariable logistic regression analysis to create a simple risk score model, with respiratory failure as the outcome for young (18–39 years), middle-aged (40–64 years) and older (≥65 years) groups, using sex, age, body mass index, medical history and symptoms. The models selected for each age group were quite different. Areas under the receiver operating characteristic curves for the simple risk score model were 0.87, 0.79 and 0.80 for young, middle-aged and elderly derivation cohorts, and 0.81, 0.80 and 0.67 in the validation cohorts. Calibration of the model was good. The simple scoring system may be useful in the appropriate allocation of medical resources during the COVID-19 pandemic.

The taxonomy of ruminant Trypanosoma theileri and its relatives (Kinetoplastida: Trypanosomatidae) is controversial, with recent phylogenetic studies segregating T. theileri in cattle and other ruminants worldwide into two major genetic lineages (the TthI and TthII clades) based on genetic markers. In the present study, T. theileri-like trypanosomes isolated from Honshu sika deer (Cervus nippon) in the western Japan (YMG isolate) were genetically characterized using a number of genetic markers. Sika deer trypanosomes of the YMG isolate were genetically different from the Trypanosoma sp. TSD1 isolate previously recorded from Hokkaido sika deer in northern Japan, with the former trypanosome isolate being genetically closer to European cervid trypanosomes and the bovine T. theileri TthII lineage. In contrast, the latter isolate exhibited greater relatedness to North American cervid trypanosomes and the bovine T. theileri TthI lineage, although a clear genetic distinction between these was apparent. Furthermore, trypanosomes in Honshu sika deer from the central part of Japan harboured additional genetic diversity and were closer to either TSD1 or YMG isolates, while distinct from known T. theileri-related genotypes. Importantly, cervids and wild ruminants worldwide might harbour divergent descendants of a T. theileri ancestor, which exhibit rigid host specificity to either bovines or cervid species.

In Thailand, two species of rhizostome jellyfish, Rhopilema hispidum and Lobonemoides robustus, are commercially harvested. The cnidomes, nematocyst size and toxicities were compared between these species. Rhopilema hispidum and L. robustus each had four types of nematocysts on their oral arms. For R. hispidum, these nematocyst types included two types of isorhiza and two types of rhopaloid, while in L. robustus, there were three types of isorhiza and one type of rhopaloid. For R. hispidum, tubule lengths of the largest nematocyst type (large round isorhiza; mean ± SD = 313.8 ± 62.2 μm) were significantly longer than those of L. robustus (large ellipsoid rhopaloid; 162.1 ± 38.5 μm). Using the freshwater shrimp, Palaemon paucidens, in a bioassay, we determined that the lethal nematocyst concentrations for R. hispidum and L. robustus were 5705.3 ± 1118.1 and 3408.3 ± 1032.9 unit g−1 wet weight, respectively, and that these concentrations were significantly higher in the former than in the latter.

A consistent description of the hydrogen permeation through metal membrane based on hydrogen chemical potential proposed has been explained in detail. The hydrogen flux is proportional to the PCT factor, f PCT, consistently, which reflects the shape of the pressure-composition-isotherm (PCT curve) of the material. In addition, in view of the PCT factor, f PCT, and the ductile-to-brittle transition hydrogen concentration, DBTC, a concept for alloy design with high hydrogen permeability and strong resistance to hydrogen embrittlement has been proposed. In this concept, it is important to design alloy composition with appropriate PCT curve under the given pressure and temperature condition. As an example, V–9 mol% Al alloy has been designed, which exhibits high hydrogen flux without brittle fracture under given condition. Thus, the new consistent description is useful not only for the understanding of the hydrogen permeation property but also for the alloy design.

The effect of arachidonic acid (ARA) intake on asthma risk is unclear. The objective of the present review was to systematically evaluate available observational studies on the relationship between ARA exposure and asthma risk in children and adults. A PubMed search was conducted on 22 October 2013 and seventy-three publications were checked against predefined criteria for eligibility. To identify additional eligible publications, potentially relevant articles were searched from bibliographies of articles on ARA and asthma. A total of 2924 citations were scrutinised. Finally, fourteen articles were included. A quality assessment was conducted based on the reporting and methodological quality. A meta-analysis was not conducted; therefore, a qualitative assessment is presented. Three high-, two medium- and ten low-quality studies were reviewed. Eleven studies, including two high- and two medium-quality studies, did not find a significant association between ARA exposure and asthma risk. In contrast, one high-quality study indicated a significant trend toward reducing asthma risk in children with decreasing maternal ARA intake (Ptrend = 0·025), and one low-quality study reported a significant trend of increasing asthma risk with higher blood ARA levels (Ptrend = 0·007). In two low-quality studies, asthma patients had significantly lower blood ARA levels than controls (both P < 0·05). These studies did not sufficiently demonstrate any relationships between ARA exposure and asthma risk because of the limited number of studies and their methodological limitations. They seem to suggest that ARA exposure is not consistently associated with asthma risk. Nevertheless, further evidence is required to prove or disprove the association.

The neutron diffraction technique was applied to measure strain distributions in a rebar in a reinforced concrete. At first, absorption coefficients of several kinds of concrete with different compounding ratios of water, cement, and aggregate were measured, and it was confirmed that the absorption coefficient of concrete was affected by the amounts of water and aggregate. In addition, it was also clarified by measuring strain change of the rebar under tensile loading that accuracy of the strain measurement in the rebar in the reinforced concrete was not affected by the neutron absorption by the concrete. Second, the size of the anchorage zone was evaluated by measuring strain distributions in the rebar under pull-out loading. The length of the anchorage zone measured by neutron diffraction was shorter than that measured by strain gauges. Moreover, detailed strain distributions in the rebar around cracks in the concrete were measured under tensile loading, and it was confirmed that the bond condition between rebar and concrete around cracks could be evaluated using the neutron diffraction technique.

We developed a new microscale technique for evaluating the local interface adhesion in a thin film stack and we compared it with a conventional four-point bending technique. Using the microscale technique, the interface adhesion was estimated to be 3.0 J/m2 by comparing experimental results with numerical simulation results for interface crack propagation behavior. The four-point bending technique was applied to the same interface and the interface adhesion was estimated to be 4.4 J/m2 by experiment. However, this value is an overestimate because it includes the plastic deformation of epoxy resin used to fabricate the specimens. By eliminating the additional energy dissipated through plastic deformation of the epoxy resin close to the interface crack tip, the interface adhesion was evaluated to be 3.3 J/m2. This value agrees well with that obtained using the microscale technique.

This paper proposes a receiver that repeats iterative frequency-domain equalization (FDE) and decision-directed phase noise compensation (DD-PNC) to alleviate degradation due to the phase noise for millimeter-wave single carrier (SC) systems. High bit-rate SC-FDE transceivers based on the single-chip Si RF-CMOS IC technology in the 60-GHz millimeter-wave band have been extensively studied for wireless personal area network (WPAN) systems, and the relatively large phase noise in a phase-locked loop (PLL) synthesizer severely degrades transmission performance. In an initial processing of the proposed receiver, a cyclic prefix (CP)-based phase noise compensator (CP-PNC) removes the phase noise from a time-domain received signal by using CP, which is known to the receiver, and the channel is equalized by the iterative FDE using the conventional minimum mean-square-error (MMSE) weight. In an iterative processing, DD-PNC estimates the phase noise each symbol by exploiting an output of a channel decoder, and then compensates the time-domain received signal for the phase noise by using the estimate. In order to equalize the compensated received signal, the iterative FDE performs both the MMSE filtering and residual inter-symbol interference cancelation using the decoder output. Computer simulations following the 60-GHz WPAN standard demonstrate that in the 64QAM with the coding rate of 3/4, the proposed receiver with three iterations can drastically remove the phase noise of −85 dBc/Hz at 1 MHz offset, and that it can achieve excellent transmission performance.

In this study, the dense films of well-crystallized ZnO nanocrystals were successfully prepared by direct spin-coating of the colloidal solution of ZnO nanoparticles derived from the microemulsion method. The average grain sizes in the films were reasonably controlled in the range from 6.5 to 34.3 nm by simply changing the annealing temperatures. The increase in band gap energies was found in the size region less than 13.3 nm, finally resulting in 3.47 eV for the average size of 6.5 nm. The photoluminescence spectra at room temperature showed intense ultraviolet (UV) emission with faint green luminescence. The Stokes shifts of the films were estimated to be one or two orders of magnitude smaller than those of the conventional ZnO nanocrystalline films, suggesting the well crystallization and slight amounts of lattice defects in the ZnO nanoparticles. These excellent features may be favorable to make high-performance optical application such as UV emitting devices.

The electrospray of a colloidal microemulsion (ME) solution and subsequent on-line annealing were used to produce barium titanate nanoparticles (BTO-NPs). The solvent of the ME solution (cyclohexane) was replaced with a high-conductivity solution (solute: ammonium acetate, solvent: tetrahydrofurfuryl alcohol, conductivity: 3.1 × 10−2 S/m) to generate ultrafine droplets during the electrospraying. Well-dispersed and well-crystallized BTO-NPs with a perovskite structure were successfully fabricated at an annealing temperature of 1173 K. The size distribution of the BTO-NPs was successfully measured by applying a differential mobility analyzer and condensation nucleation counter to nanoparticles in-flight. The average size of the BTO-NPs was controlled within a range of 15 to 25 nm by changing the feeding rate. The electrospray of an ME solution with lower conductivity (solvent: 1-octanol, conductivity: 7.0 × 10−4 S/m) yielded amorphous particles with larger particle sizes. Thus, the electrospray of a high-conductivity solution is required to fabricate well-crystallized and dense BTO-NPs with smaller particle sizes.

For a formation of metal hydride of MgH2 or AlH3 under room temperature and ambient pressure, the cathode electrodes of metal and lithium hydride are electrochemically charged with Li anode electrodes in the system of Li-ion extraction. For MgH2 formation, the VC (Voltage-Composition) curve of Mg + 2LiH during charge shows a plateau voltage at 0.6 V until the final composition of 1.05 Li extraction. After charge MgH2 phase is observed by the XRD measurement. Therefore MgH2 is produced by the electrochemical charge from Mg and LiH. For AlH3 formation, Al + 3LiH is charged until the final composition of 0.6 Li at a plateau voltage of 0.8 V which corresponds to the reaction between Al and LiH for the formation of AlH3. In the XRD profile after charge AlH3 phase is not detected although the intensities of Al and LiH decrease compared with these before charge, which suggests the reaction leading to the formation of AlH3.

Production of biodiesel fuel (fatty acid methyl ester) by use of conventional method (alkaline catalyst method) requires deacidification process prior to the reaction and refining process to remove the catalyst after the reaction. These processes increase total cost required for production of biodiesel fuel. In order to solve the problem, authors recently proposed a method called superheated methanol vapor method. In a process with this method, superheated methanol vapor is continuously bubbled into the oil in the reactor vessel and reacted with triglycerides to form fatty acid methyl ester and glycerol. The fatty acid methyl ester and glycerol formed flows out of the reactor together with unreacted methanol vapor and is collected using a condenser. Reaction using the superheated methanol vapor method can be conducted at atmospheric pressure. Production of fatty acid methyl ester by use of the superheated methanol vapor method does not require refining process after the reaction because no catalyst is used in this method and fatty acid methyl ester can be separated from glycerol simply by sedimentation. The method does not require deacidification process prior to the reaction because not only triglyceride but also free fatty acid can be converted into fatty acid methyl ester by use of the method. Therefore, both initial and running costs required for biodiesel production are thought to be reduced by applying the method. In order to estimate the cost required by a process based on the superheated methanol vapor method, a demonstration plant (design productivity: 400 L/d) was constructed and its efficiency was evaluated. The plant could produce 425 L of fatty acid methyl ester in a day from used frying oil. Energy consumed in each unit of the demonstration plant was measured (electrical energy and thermal energy). Based on the energy consumption data obtained with the demonstration plant, production cost required with a practical scale plant (designed productivity: 6000 kL/y) was calculated. The cost required by the practical scale plant with the superheated methanol vapor method was estimated to be 40.2 yen/L (about 40 cent/L) while the cost required by a plant with the alkaline catalyst method was 62.5 yen/L (about 62 cent/L). The estimated cost includes depreciation cost, cost of repairing, labor cost, methanol cost and energy cost (heat and electricity). Most of the energy consumed by the plant was thermal energy and the plant could be automatically controlled. Therefore, required cost will be further decreased by installing the plant next to an incineration facility because thermal energy can be supplied from the facility and the labor cost can also be supported by the facility.

Colonic fermentation products, SCFA, have various effects on colonic functions. Here, we found that physiological concentrations of SCFA immediately promote epithelial barrier function in the large intestine. Solutions of mixed and individual SCFA were applied to the caecal walls mounted on Ussing-type chambers. Transepithelial electrical resistance (TER) increased rapidly and reached a peak 35 % higher than that in the control specimen within 10 min post application of the SCFA mixture (80 acetate, 40 propionate, 20 butyrate (mmol/l)). The Lucifer yellow permeability, a paracellular transport marker, was dose-dependently reduced by the mixed SCFA, acetate and propionate solutions. Inhibition of monocarboxylate transporter-1 did not influence the increase in TER with acetate; however, lowering the pH (from 7·5 to 5·5) clearly enhanced the effect of acetate. Non-metabolizable, bromo and chloro derivatives of SCFA also increased TER. These results suggest that passive diffusion of SCFA is dominant and the metabolism of SCFA is not required for the promotive effect of SCFA on barrier function. We also observed that individual SCFA dose-dependently increased TER in T84 and Caco-2 cells, which indicates that SCFA directly stimulate epithelial cells. Depletion of membrane cholesterol and inhibitors of phosphatidylinositol-3 kinase and Gq protein attenuated the acetate-mediated promotive effect. Finally, we found that the mucosal application of the SCFA mixture dose-dependently suppressed [3H] mannitol transport from the caecal lumen to the mesenteric blood in the anaesthetized rats. We conclude that physiological concentrations of SCFA immediately enhance barrier function of the colonic epithelium through cholesterol-rich microdomain in the plasma membrane.