One Pot Cooking of Rice Grains for Preparation of Rice-Gel Samples Using a Small-Scale Viscosity Analyzer: Small-scale Rice-gel Preparation from Grains

Rice-gel prepared by the following three steps: rice grain cooking, shearing of the cooked rice, and cooling for gel formation, is expected as a novel food ingredient for modification of various food products such as bread and noodles. To meet the demand for high-throughput systems for research and developments on the new rice gels, herein we established a mini-cooking system for preparation of rice gel samples from grains using a small-scale viscosity analyzer (Rapid Visco Analyzer; RVA). Polished rice grains (4 g) were cooked with 22 mL of water in a canister, and the paddle equipped in the canister was rotated at 2,000 rpm for 30 min (80 °C was used as a representative) to shear the cooked rice. The sheared paste was cooled to 10 °C at 160 rpm, and the initial gelation property was evaluated by viscosity analysis within the RVA. Alternatively, the sheared paste was transferred to an acrylic mold and kept at 4 °C for 0, 1, 3, and 5 days for determination of the hardness with a compression test. Compressive forces required to penetrate 20 % thickness for three tested rice cultivars were measured, and the trend of the value shifts during preservation is similar to the corresponding trend obtained in 300-g grain scale laboratory tests, whereas the individual values were halved in the former. This small cooking method could offer a useful assay system for a rapid evaluation in the breeding programs and in the high-throughput screening of additives for the modification of properties.     

Determination of various constituent elements of polyethylene terephthalate bottles used for beverages in Japan

Polyethylene terephthalate (PET) bottles are some of the most commonly used containers for beverages. During the manufacturing process of PET resin in Japan, metallic catalysts such as Sb and Ge are widely used, with other metals or metallic compounds also being employed to improve the quality of PET bottles. However, few reports into the contents of such elements exist. Thus, we herein report the concentrations of 34 elements (ie, Li, B, Na, Mg, Al, P, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, As, Se, Rb, Sr, Zr, Mo, Ag, Cd, Sn, Sb, Cs, Ba, W, Pb, and U) in 16 samples of unused virgin PET bottles for beverages. The measurement was performed by inductively coupled plasma optical emission spectrometry (ICP-OES) and inductively coupled plasma mass spectrometry (ICP-MS), and these bottles were found to contain five main elements (ie, <0.5- to 50-mg/kg Ge, <1- to 26-mg/kg Ti, <0.1- to 279-mg/kg Sb, <10- to 48-mg/kg P, and <0.5- to 53-mg/kg Co) that were used as polymerisation catalysts, stabilisers, oxidation catalysts, and bluing agents. Furthermore, when these residual element concentrations in 21 commercial mineral-water PET bottles were determined, there was no significant difference from unused bottles.     

Fabrication of silica/platinum core-shell particles by electroless metal plating

An electroless metal plating method was used to form Pt shells on sub-micrometer-sized silica (SiO₂) particles fabricated by a sol-gel method. The electroless metal plating method was comprised of three steps: (1) surface-modification of SiO₂ particles with polyvinylpyrrolidone (PVP) (SiO₂/PVP) or poly-diallyldimethylammonium chloride (PDADMAC) (SiO₂/PDADMAC), (2) pre-deposition of Pt nuclei or Pt fine particles on the SiO₂ particles by reducing Pt ions in the presence of SiO₂/PVP particles (SiO₂/PVP-Pt) or SiO₂/PDADMAC particles (SiO₂/PDADMAC-Pt), and (3) growth of the pre-deposited Pt by immersing the SiO₂/PVP-Pt or SiO₂/PDADMAC-Pt particles in a Pt-plating solution. The pre-deposition of Pt nanoparticles was successfully performed for the surface-modified SiO₂ particles since the surface modification possibly strengthened the affinity between the SiO₂ particle surfaces and Pt ions. The Pt nanoparticles were pre-deposited more uniformly in the case of PVP because the pre-deposition took place more slowly for the PVP, which provided uniform surface-modification followed by the uniform pre-deposition of Pt nanoparticles. The formation of Pt shells was successfully performed on the SiO₂/PVP-Pt particles in the electroless metal plating process because Pt nuclei were generated by the reduction of H₂PtCl₆ and then further deposited on the Pt particle surfaces on the SiO₂/PVP-Pt particles.     

Tailoring Multistimuli Responsive Micropatterns Activated by Various Mechanical Modes

A versatile wrinkle-based micropatterned system with a film-substrate structure is proposed, which contains a hydrophilic film of polyvinyl alcohol or its composite with laponite and a hydrophobic substrate of polydimethylsiloxane or its composite with carbon black. The wrinkled system features high design flexibility and multistimuli responsiveness, which can be activated by various mechanical methods, including vertical press or scratch, gentle stretch-and-release, bend, or analogous magneto-mechanical and electro-mechanical modes. The resultant wrinkles possess 1) instantaneous and reversible strain/moisture/light responsive optical modulation; 2) tunable dynamics for the aforementioned strain/moisture/light response;3) tailorable amplitude/wavelength; 4) unique surface morphologies from the coupling of wrinkles and cracks; 5) excellent reversibility and durability. A variety of applications are demonstrated based on this system, including 1) a moisture erasable highly sensitive pressure responsive device and pattern replicator with a high fidelity; 2) a moisture erasable scratch/magneto-mechanical re-writable tablet; 3) an electro-mechanical controllable smart window with an ultra-sensitive strain responsive transmittance modulation and a low operating voltage; 4) various types of strain responsive, moisture erasable, and laser writable information recording/encryption devices. This work provides new routes for designing innovative wrinkled systems triggered by diverse mechanical fashions and can decode multiple environmental stimuli into optical signals for widespread application.     

Synthesis and Evaluation of a Series of Bis(pentylpyridinium) Compounds as Antifungal Agents

A series of bis(4‐pentylpyridinium) compounds with a variety of spacers between the pyridinium headgroups was synthesised, and the antifungal activity of these compounds was investigated. Lengthening the alkyl spacer between the pentylpyridinium headgroups from 12 to 16 methylene units resulted in increased antifungal activity against C. neoformans and C. albicans, but also resulted in increased hemolytic activity and cytotoxicity against mammalian cells. However, inclusion of an ortho‐substituted benzene ring in the centre of the alkyl spacer resulted in decreased cytotoxicity and hemolytic activity, while maintaining antifungal potency. Replacement of the alkyl and aromatic‐containing spacers by more hydrophilic ethylene glycol groups resulted in a loss of antifungal activity. Some of the compounds inhibited fungal PLB1 activity, but the low correlation of this inhibition with antifungal potency indicates PLB1 inhibition is unlikely to be the predominant mode of antifungal action of this class of compounds, with preliminary studies suggesting they may act via disruption of fungal mitochondrial function.     

A study on a porous residential building model in hot and humid regions: Part 1—the natural ventilation performance and the cooling load reduction effect of the building model

This study targets environmental load reduction in hot and humid regions. It reveals the effects that porous residential buildings have on the natural ventilation performance and, consequently, the cooling load reduction. Two residential building models, namely a model with a void ratio of 0% and a model with a void ratio of 50%, are evaluated using computational fluid dynamics (CFD) analysis and thermal and airflow network analysis. The analysis on components of the heat load indicates that improvements in the natural ventilation performance would significantly reduce the cooling load.     

High speed and reproducible analysis of nitrosamines by capillary electrophoresis with a sulfonated capillary

Recently environmental control is regarded as important for good human health conditions, and toxic substances, including carcinogens and endocrine disruptors should be eliminated from our living environment. Hence easy quantitative methods are expected for a high level of environmental control. Our previous paper describes an easy quantitative analysis of nitrosamines (NAs) by capillary electrophoresis with an untreated fused silica capillary installed in an ordinary apparatus. In this paper, utilizing a novel type capillary column having sulfonated inner wall was investigated for improvements of separation performance and reproducibility. A sulfonated capillary causes fast and stabile electroosmotic flow because its inner wall is strongly negative charged. On a performance comparison of a sulfonated capillary with an untreated fused silica, analysis time reduction of c.a. forty percent was achieved, and relative standard deviations of migration times and peak responses were less than one third. In addition sample concentrations giving detection and quantitation limits were also reduced to a half.