Discovery of unusual regional social activities using geo-tagged microblogs

The advent of microblogging services represented by Twitter evidently stirred a popular trend of personal update sharing from all over the world. Furthermore, the recent mobile device and wireless network technologies are greatly expanding the connectivity between people over the social networking sites. Regarding the shared buzzes over the sites as a crowd-sourced database reflecting a various kind of real-world events, we are able to conduct a variety of social analytics using the crowd power in much easier ways. In this paper, we propose a geo-social event detection method by finding out unusually crowded places based on the conception of social networking sites as a social event detector. In order to detect unusual statuses of a region, we previously construct geographical regularities deduced from geo-tagged microblogs. Especially, we utilize a large number of geo-tagged Twitter messages which are collected by means of our own tweets acquisition method in terms of geographic relevancy. By comparing to those regularities, we decide if there are any unusual events happening in monitoring geographical areas. Finally, we describe the experimental results to evaluate the proposed unusuality detection method on the basis of geographical regularities which are computed from a large number of real geo-tagged tweet dataset around Japan.     

Growth of Pt Subnano Clusters on Limited Surface Areas of Prussian Blue Nanoparticles

We synthesized insoluble Prussian blue nanoparticles (PB NPs) and water-soluble PB NPs ([Fe(CN)₆]^4?-modified PB NPs) as synthetic fields and carriers of Pt subnano clusters. Pt²⁺ can attach on their surface Fe–CN sites. The amount of the attached Pt²⁺ on the insoluble and water-soluble PB NP surfaces was saturated to reach Pt/Fe = 15 and 40 mol%, respectively, based on the total metal ions of PB. The results showed that the attachment amount of Pt²⁺ on the surface CN sites was controlled by the surface modification. From results of TEM and STEM-HADDF-EDS, Pt subnano clusters (1.4 nm) were observed on water-soluble PB NPs after the reduction using hydrazine.     

Laboratory performance study of the quantitative detection method for genetically modified soybeans (roundup ready soybeans 40-3-2)

To investigate important factors affecting the analytical results, a laboratory-performance study was attempted for the Japanese official methods to detect genetically modified (GM) soybeans (40-3-2). Test samples containing 0, 1 and 5% GM soya powder in non-GM soya powder was prepared. A set of 3 test samples was sent to the participating laboratories along with the protocol. The data were collected from all laboratories and statistically analyzed. In the real-time PCR detection method, the average values of the GM 1% and 5% samples were both much lower than the spiked value because the laboratories using a silica-membrane DNA extraction method underestimated the GM value. On the other hand, the laboratories using other extraction methods, such as the CTAB method obtained values close to the spiked value. These results suggest that use of the silica-membrane DNA extraction method may result in underestimation of the GM content in the real-time PCR method. In the ELISA method, the average value of 5% spiked samples appears to be slightly higher than the fortified value. But, overall, it was considered that reported values were close to the spiked level.     

A solid–solid extraction

When a vessel containing two equal-sized particle species is subjected to vibration with an acceleration significantly greater than 1g, the particle bed sometimes separates into two clear-cut layers, the bottom layer consisting only of the lighter particles. This paper shows that the above inverse density segregation can be used to perform a solid–solid extraction. A mixture of equal-sized glass and steel beads (1290 μm in mean diameter) did not separate into two layers under vibration. However, when equal-sized lead beads were added to the mixture and the three-component mixture was subjected to vibration the bed separated into two clear-cut layers, the top layer being the mixture of the three components, the bottom layer consisting only of glass beads. The scale effect and the underlying mechanisms of this solid–solid extraction are discussed.     

RNA‐Directed Amino Acid Coupling as a Model Reaction for Primitive Coded Translation

The stereochemical theory claims that primitive coded translation initially occurred in the RNA world by RNA‐directed amino acid coupling. In this study, we show that the HIV Tat aptamer RNA is capable of recognizing two consecutive arginine residues within the Tat peptide, thus demonstrating how RNA might be able to position two amino acids for sequence‐specific coupling. We also show that this RNA can act as a template to accelerate the coupling of a single arginine residue to the N‐terminal arginine residue of a peptide primer. The results might have implications for our understanding of the origin of translation.     

Organic–inorganic hybrid material as zwitterion: Synthesis and structure of terminal ammonium ions-containing organosilyl species supported on mono-lacunary Dawson polyoxometalate

The title compound 1 with a formula of (Bu₄N)₄[α₂-P₂W₁₇O₆₁{Me₃N⁺(CH₂)₃Si}₂O] · CH₃CN was obtained in 77.1% (4.21 g scale) yield by a 1:2 molar-ratio reaction of the mono-lacunary Dawson polyoxometalate (POM) [P₂W₁₇O₆₁]¹⁰⁻ with N-trimethoxysilylpropyl-N,N,N-trimethylammonium chloride ([Me₃N(CH₂)₃Si(OMe)₃]Cl) in mixed water/acetonitrile solution under acidic conditions and unequivocally characterized with complete elemental analysis, thermogravimetric and differential thermal analyses (TG/DTA), FTIR, solution (³¹P, ¹H, ¹³C and ²⁹Si) NMR and X-ray crystallography. Compound 1 contained two types of the ammonium cations, i.e., the counterions Bu₄N⁺ (free cations) and the terminal quaternary ammonium ions (bound cations) which are connected to the POM through the organosilyl groups.     

Flow-induced stripe pattern formation in phase-separating fluids

We demonstrated that the introduction of a temperature gradient along the free surface induces a particular stripe pattern in phase-separating fluids. The horizontal temperature gradient drove lateral-periodic spiral liquid motion flowing from warmer to cooler places due to thermocapillarity. Properly chosen polymer compositions and initial film thicknesses in ternary solutions allowed us to promote a phase separation in the presence of spiral flow, which assembled the demixed polymer droplets along the flow-stagnation lines. The resulting assembled phases aligned in the temperature gradient direction and eventually formed periodic polymer stripes involving the same spacing as that of the flow axis. The critical condition for the stripe pattern formation was given by the ratio of two relevant film thicknesses, i.e. the thickness for the onset of the phase separation and that for the cessation of liquid motion.     

Evolution of Interfacial Microstructure between Barium Titanate and Binary Glasses

Evolution of interfacial microstructure between BaTiO₃ and the binary glasses used as frits in thick-film technology has been studied. Possible reaction mechanisms for the interfacial compounds have been determined by comparing the results of the sintering study with the reaction of BaTiO₃, powder with glass powders. The interfacial microstructure can be divided into two types. The first type of interfacial microstructure is observed for glasses rich in PbO or Bi₂O₃ network modifiers and is characterized by the penetration of glass into the BaTiO₃ grain boundaries, accompanied by incorporation of Pb into the perovskite lattice. The second type of interfacial microstructure is observed for glasses rich in B₂O₃ or SiO₂ network formers and is characterized by the formation of interfacial compounds.