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A refinement of undefeated equilibria avoids the problems posed by sequential equilibria that limit the usefulness of games of incomplete information, and an existence theorem on signalling games is provided. Difficulties in implementing the concept of forward induction are explained. The set of undefeated equilibria in continuous strategy set signalling games is shown to be non-empty, and proofs are presented.

Several conceptual points are made concerning communication in games of asymmetric information. Equilibrium refinements of Sender-Receiver cheap-talk games that are based on the concept of a putative equilibrium, and which rely on the presence of a rich language with literal meanings, are discussed. Three nested criteria are proposed: strong announcement-proofness, announcement-proofness, and weak announcement-proofness. Journal of Economic Literature Classification Number: 026.

Abstract The efficient modification of zeolites for improving their catalytic properties is a significant subject of microporous materials chemistry. H-ZSM-5 zeolite is a potent catalyst of the production of propylene as an important start material of a variety of chemical products, which is mainly obtained from fossil resources. Recently, the production of propylene using non-fossil carbon resources are desired because of the depletion risk of fossil fuels and global warming problem. Dimethyl ether (DME) conversion to propylene is actively studied using acid catalysts as an alternative synthetic route of propylene. This paper reports the propylene production from DME using H-ZSM-5 catalyst whose surface was modified with an organo-disilane compound, 1,4-bis(hydroxydimethylsilyl)benzene. An H-ZSM-5 catalyst surfacely modified with the disilane compound produced propylene from DME in higher yield than original (non-modified) H-ZSM-5. Air flow treatment at 480 °C effectively regenerated the modified H-ZSM-5 that was deactivated by coke formation during the reaction, and this regenerated catalyst had a nearly equivalent activity of the propylene production to the catalyst before deactivation. The polycyclic aromatic compounds formed from the benzene ring of the disilane compound that covered the exterior surface of H-ZSM-5 controlled the catalytic activity to increase the yield of propylene. Graphical abstract Image 1 Highlights • 10% of 1,4‒bis(hydroxydimethylsilyl)benzene was modified on H-ZSM-5 zeolite. • The modified H-ZSM-5 was effective for propylene synthesis from dimethyl ether. • Propylene yield by the modified H-ZSM-5 was more than double of that by H-ZSM-5. • Polycyclic aromatics was formed of the disilane compound on the surface of H-ZSM-5. • Restricting the reaction at exterior surface of H-ZSM-5 improved propylene synthesis. [ABSTRACT FROM AUTHOR]

The production of purified water by seawater desalination is now a significant countermeasure against recent severe water shortage. As the global warming is thought to be a dominant cause of the water scarcity problem, the energy employed for the desalination should be free from fossil fuels. We recently reported a simple membrane desalination combining the harvesting of solar energy and the membrane permeation of vaporized water. Water on a PTFE (polytetrafluoroethylene) membrane modified with disperse red 1 (DR1) as an azobenzene dye that photo-isomerizes with visible light permeates through it under visible light irradiation. The penetrated water was efficiently desalinated to produce purified water by membrane distillation mechanism, where water was evaporated by DR1 using solar energy. In this paper, we report that the aqueous solution of rhodamine B on non modified PTFE membrane permeated the membrane to be purified under visible light irradiation. This paper also reports that a PTFE membrane modified with disperse blue 14 (DB14) was active for the desalination. Thus, even these non-azobenzene dyes were revealed to be available for the light induce water permeation. When DR1 and DB14 were modified to PTFE membrane concurrently, a higher performance of seawater desalination using simulated sunlight was achieved by efficient absorption of the irradiated light with DR1 and DB14. [ABSTRACT FROM AUTHOR]

A variety of advanced functions such as hydrophilicity and hydrophobicity are required for transparent glass plates recently. This paper reports a new procedure to produce transparent silica thin films on glass plates obtained from sodium silicate as inexpensive silica source by its dip coating and subsequent deposition of silica with (NH 4 ) 2 SO 4 solution. When the thin films were prepared using bovine serum albumin (BSA), the resulting transparent films became more hydrophobic than that obtained without BSA and had good adhesion with water droplet, the so-called “petal effect”. Water droplet on the silica thin film did not slide down even when the substrate turned vertically and upside down. Although no BSA was included in the silica thin film, BSA contributed to the formation of nano-sized asperity structures in the film, producing more hydrophobic (less hydrophilic) property and the petal effect. [ABSTRACT FROM AUTHOR]

Abstract: The direct encapsulations of proteins such as lysozyme, bovine serum albumin (BSA) and ovalbumin into calcium silicate microparticles were examined by interfacial reaction method using water/oil/water emulsion (W/O/W emulsion), which was effective for the preparations of silica and calcium carbonate microcapsules encapsulating biomacromolecules. Those proteins added to the sodium silicate solution of the W/O/W emulsion were successfully encapsulated into the microparticles, which were ascertained by diffuse reflectance ultraviolet (UV) and infrared spectra. The encapsulation efficiency of the proteins depended on the molecular weight of proteins, which were also observable in the protein encapsulations into silica and calcium carbonate microcapsules. No discharge of encapsulated proteins by simple washing with deionized water indicated the secure packing of proteins into calcium silicate matrix. Ethylenediamine-N,N,N′,N′-tetraacetic acid, tetrasodium salt (EDTA·4Na) effectively extracted calcium ions from the microparticles to serve as a trigger for the release of proteins, indicating that the elimination of calcium ion initiated the discharge of encapsulated proteins. The ion exchange between calcium and sodium ions also achieved the release of proteins into aqueous solutions. The release rate of proteins such as lysozyme and BSA increased with the concentration of sodium chloride less than 1M. In diluted solutions, potassium chloride accelerated the protein release more than sodium chloride. These characteristic release behaviors must be applied to drug delivery systems that respond to the concentration of alkaline ions in body fluid. [Copyright &y& Elsevier]

Abstract: The controls of oxygen permeation including oxygen delivery to the circumstances without sufficient oxygen supply from the atmosphere are important technologies for chemical and environmental engineering. The combination of the storage of molecular oxygen into the small pore voids and the appropriate discharge to the outside is a promising technique for a new method of oxygen supply. We recently showed that the surface modification of mordenite with organo-disilane compounds blocked the permeation of molecular nitrogen into the micropores. This result suggested that the grafting of the organo-disilane compounds on zeolite surface is also available for controlling oxygen permeations. In this paper, the oxygen storage in the pore void of mordenite was attempted by the modification method under pressurized oxygen atmosphere. A proton type of mordenite with impregnated 1,4-bis(hydroxydimethylsilyl)benzene was heated at 150°C under pressurized oxygen flow of 10bar. When this oxygen-filled mordenite sample was heated at 230°C under argon flow after sufficient deaeration of residual oxygen in dead space, clear decreases of oxygen releasing to the flow were found. A partial oxidation of the organo-disilane compound took place by the oxygen discharged from the micropore, which was supported by the formation of a partially oxidized benzene species of the organo-disilane compound in the treated sample. Although the direct extract of free oxygen was still unsuccessful, this might be the first example that the molecular oxygen is stored in the micropore of mordenite by the effective sealing of the micropore. [Copyright &y& Elsevier]

Abstract: Although the versatilities of zeolitic materials are widely known to chemists and materials scientists, their exclusive microporosity sometimes causes various defections especially in the diffusion of reactant and product molecules in catalytic reactions. Silica–alumina/epoxy-resin composite materials were obtained from TMOS (tetramethoxysilane), aluminum acetylacetonate and bisphenol A diglycidyl ether with a cyclic acid anhydride as both condensation and curing reagents. Hydrothermal treatment of the composite materials with TPAOH (tetra-n-propylammonium hydroxide) crystallized the amorphous silica–alumina part to the MFI zeolite crystalline phase and induced the phase separation of epoxy-resin domain from the zeolite phase at the same time, forming both zeolite microporosity and mesoporosity in the solid catalyst after calcination. The mesoporous MFI zeolite thus prepared had a good catalytic activity in liquid phase Friedel–Crafts benzylation reaction. The mesoporous channels fabricated in the MFI zeolite material enhanced the diffusion of reactants and products in the solid matrix, and thus it showed a better catalytic activity in the benzylation of toluene together with the high selectivity of the mono-substituted para-isomer. The new methodology reported in this paper to produce the mesoporous zeolite materials will promote the chemistry and the applications of zeolite catalysts and related materials. [Copyright &y& Elsevier]

Abstract: Regularly-structured solid matrices are potent materials for regulating molecular permeation and diffusion. Zeolite materials bearing ordered micropores are very advantageous to control the diffusion of molecules. When some disilylbenzene compounds were grafted on mordenite and ZSM-5 zeolites, the penetrations of small molecules such as α-methylstyrene (AMS) and molecular nitrogen were prevented by the direct formation of the crosslinking with two grafting sites on the exterior surfaces of those zeolites. The dimerization reaction of α-methylstyrene effectively promoted by mordenite was not catalyzed by these grafted mordenite samples. No adsorptions of molecular nitrogen were observed in the grafted mordenite and ZSM-5 samples. When these grafted samples were calcined, both the catalytic activity for the dimerization and the permeation of molecular nitrogen were recovered. The reopening of the micropores of zeolites was also achieved by the treatment with HCl acidic solutions. Thus, the diffusion and the permeation of various small molecules can be perfectly and reversely controlled by the sealing and the reopening of the micropores of zeolites by the disilylbenzene compounds. [Copyright &y& Elsevier]

Abstract: Mesostructured calcium phosphate was synthesized by means of the combination of a soluble metal salt with an aqueous phenylphosphonic acid solution containing sodium dodecyl sulfate (SDS). Phenylphosphonic acid (PhP) was selected as the template to pattern the materials with pores generated by the formation of a lamellar calcium PhP phase. SDS was introduced to improve the thermal stability of the pore structure. The resulting materials were characterized by means of X-ray diffraction (XRD), small-angle X-ray diffraction (SAXS), electron microscopes and BJH gas absorption method. With the aid of SDS, calcium phosphate materials with the surface area and pore volume as 72m2/g and 569cm3/g, respectively, were successfully developed at the SDS:PhP molar ratio of 0.3:1. It was found that the addition of SDS could effectively improve the thermal stability of the pore structure. A possible mechanism was proposed to interpret the formation procedure and the improved thermal stability of the mesoporous structure. [Copyright &y& Elsevier]

Abstract: We reported before that inorganic reaction occurring at the interface of W/O/W emulsion is advantageous to produce hollow spheres (microcapsules) of inorganic matrices such as silica. This process enables us to include various materials into inorganic matrices directly. Calcium phosphates were also produced from NH4H2PO4 and Ca(OH)2 by this interfacial reaction method. Various biomaterials are directly incorporated into crystalline calcium phosphate matrices, when the biomaterials are added to the inner water phase of the W/O/W emulsion. ZrO2 and Al2O3 powders were effectively encapsulated in calcium phosphates such as hydroxyapatite (HAp). The images of backscattered electron of FE–SEM observations indicated that ZrO2 particles were included in HAp, while they adhered to the surface of HAp in the case of a simple precipitation method. Biomacromolecules such as BSA and duplex DNA were also included in HAp using the inner water phases dissolving them. Fluorescent microscopy observations revealed that biomacromolecules incorporated in HAp localized in some domains of the HAp matrices. Biomacromolecules thus included were scarcely liberated into deionized water, indicating their strong encapsulation in HAp. This general and simple methodology will provide various composite materials of calcium phosphates, which are applicable to regenerative medicine, DDS, GDS and more. [Copyright &y& Elsevier]

Abstract: Novel mesoporous organic–inorganic hybrid tantalum oxophenylphosphate has been synthesized hydrothermally by self-assembly of anionic surfactant sodium dodecyl sulfate (SDS) as structure directing agent under mild alkaline pH conditions. The mesostructure was stable on calcinations in the presence of air and during calcination at 723K it transformed into pure mesoporous tantalum oxophosphate. Detailed characterizations including elemental analysis, solid state MAS NMR, UV–vis and FT-IR spectroscopic studies suggested the incorporation of phenyl groups in the mesoporous framework and the XRD, N2 sorption and TEM data suggested wormhole-like mesopore structure in these novel materials. The mesoporous tantalum oxophenylphosphate can be sulfonated by fuming sulfuric acid and the sulfonated derivative showed excellent proton conductivity at room temperature. [Copyright &y& Elsevier]

Abstract: A novel organic–inorganic hybrid mesoporous niobium oxophenylphosphate was synthesized by using supramolecular assembly of sodium dodecylsulfate molecules. X-ray diffraction, transmission electron microscopic image and N2 adsorption data indicated the formation of a wormhole-like disordered mesostructure in the sample. The 13C and 31P MAS NMR, FTIR, UV–visible spectroscopic data and chemical analysis results indicated that all P atoms are attached to phenyl groups directly and these are combined with Nb atoms through O atoms. Calcination of this hybrid material yielded an organic-free mesoporous niobium oxophosphate material. [Copyright &y& Elsevier]

Purpose: A major drawback of magnetic resonance imaging (MRI) is its limited imaging speed. This study proposed an ultrafast cervical spine MRI protocol (2 min 57 s) using deep learning-based reconstruction (DLR) and compared the diagnostic results to those of conventional MRI protocols (12 min 54 s).Methods: Fifty patients who underwent cervical spine MRI using both conventional and ultrafast protocols, including sagittal T1-weighted, T2-weighted, short-TI inversion recovery, and axial T2*-weighted imaging were included in this study. The ultrafast protocol shortened the acquisition time to approximately-one-fourth of that of the conventional protocol by reducing the phase matrix, oversampling rate, and number of excitations, and by applying compressed sensing. To compensate for the decreased signal-to-noise ratio caused by acceleration, noise reduction using DLR was performed. For image interpretation, three neuroradiologists graded or classified degenerative changes, including central canal stenosis, foraminal stenosis, endplate degeneration, disc degeneration, and disc hernia. The presence of other pathologies was also recorded. Given the absence of a reference standard, we tested the interchangeability of the two protocols by calculating the 95% confidence interval (CI) of the individual equivalence index. We also assessed the inter-protocol intra-reader agreement using kappa statistics.Results: Except for endplate degeneration, the 95 % CI of the individual equivalence index for all variables did not exceed 5 %, indicating interchangeability between the two protocols. The kappa values ranged from 0.600 to 0.977, indicating substantial to almost perfect agreement.Conclusions: The proposed ultrafast MRI protocol yielded almost equivalent diagnostic results compared as the conventional protocol. [ABSTRACT FROM AUTHOR]

Thin-film particles of graphite oxide were synthesized in high yield by the modified Hummers’ method, in which a very long oxidation period was combined with a high purity purification process. The particles obtained had an average thickness of several nanometers and an average width of about 20 μm. The yield was 122 wt% based on the raw graphite and the recovery of carbon was 68%. Moreover, excellent flexibility of the particles was observed for the original particle(s) itself, for the particle in matrix polymer, and for two kinds of secondary conformations (lamination-layer-aggregate and random-shape-aggregate). As generally expected and already observed partially, if the affinity between the particle and the dispersion medium was very high, the thin-film particle extended well, though a local crease or a large bend could be generated. At a medium degree of affinity, the particle slightly bent, and at very low affinity, the particle(s) randomly aggregated. [Copyright &y& Elsevier]