Electrodeposition of platinum and silver into chemically-modified microporous silicon electrodes

ABSTRACT: Electrodeposition of platinum and silver into hydrophobic and hydrophilic microporous silicon layers was investigated using chemically-modified microporous silicon electrodes. Hydrophobic microporous silicon enhanced the electrodeposition of platinum in the porous layer. Meanwhile hydrophilic one showed that platinum was hardly deposited within the porous layer and a filmy growth of platinum on the top of the porous layer was observed. On the other hand, the electrodeposition of silver showed similar deposition behavior between these two chemically-modified electrodes. It was also found that the electrodeposition of silver started at the pore opening and grew toward the pore bottom, while a uniform deposition from the pore bottom was observed in platinum electrodeposition. These electrodeposition behaviors are explained on the basis of the both effect, the difference in overpotential for metal deposition on silicon and on the deposited metal, and displacement deposition rate of metal.     

'Landscape' in the Japanese language: Conceptual differences and implications for landscape research

Increasing emphasis on discussing environmental issues at a global level and a rising number of international research projects make it necessary to locate key concepts of international discourses in their cultural context and to pay attention to possible cultural differences. The aim of this paper is to analyse the concepts behind different terms used in Japanese to describe 'landscape' in order to provide an example of the equivalence problem, which is a crucial issue in inter-cultural discourses. The results of ten interviews with theoretically sampled participants suggest that the two terms Fukei and Keikan coexisting in Japanese usage, represent two distinguishable landscape concepts with different meanings and images of landscape as well as different discursive contexts. This indicates a lack of equivalence in two ways. First, the two landscape concepts in contemporary Japanese differ and are not interchangeable. Second, this situation raises the question, whether it is possible to identify terms in other languages that are comparable to the differentiations found in the Japanese language. The implications for landscape research resulting from the different concepts of landscape in Japanese found in this study are discussed.     

Formation mechanism of surface scale defects in hot rolling process

Thick oxide scale on steel may result in serious surface defects on hot-worked products. Yield efficiency and productivity of processes are considerably deteriorated by formation of defects. It is highly demanded to establish a way to produce hot-worked steels free from surface defects by controlling oxide scale. The oxide scale shows various behaviors in hot rolling; (a) uniform deformation with matrix steel, (b) cracking, (c) fragmentation, (d) indentation to matrix steel, etc. Through observations using glass coating, it is found that the behavior strongly depends on the rolling temperature as well as the scale thickness before rolling. Temperature drop due to contact with cold rolls is found to cause the cracking and a major reason for the thickness dependence. It is found that the scale cracking is predictable using the estimated scale temperature and the ductile-brittle transition temperature of Wustite (FeO). Then, methodology to produce hot rolled steels without surface defects in industrial processes is presented.     

Characterization of Antioxidants Extracted from Thai Riceberry Bran Using Ultrasonic-Assisted and Conventional Solvent Extraction Methods

Riceberry bran (RBB), a waste product from rice processing, contains several antioxidants with potential health benefits. This study aims to compare the two main parameters affecting the extraction efficiency of antioxidants from RBB, namely, the extraction technique (ultrasonic-assisted extraction (UAE) and conventional solvent extraction) and solvent (ethanol and d-limonene). The highest values of total phenolic content, total flavonoid content, total anthocyanin content, and antioxidant activity using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity and ferric reducing antioxidant power (FRAP) assays were detected in ethanolic extracts obtained by UAE. High-performance liquid chromatography investigation of the chemical composition of RBB revealed five major groups of antioxidants: (1) phenolic acids, including protocatechuic acid, vanillic acid, p-coumaric acid, ferulic acid, and sinapic acid; (2) flavonoids, including rutin, myricetin, and quercetin 3-glucuronide; (3) anthocyanins, including cyanidin 3-glucoside and peonidin 3-glucoside; (4) vitamin E, including γ-tocotrienol, β-tocotrienol, δ-tocopherol, γ-tocopherol, and α-tocopherol; and (5) γ-oryzanol. Protocatechuic acid exhibited the highest DPPH radical scavenging activity and FRAP values, whereas the lowest values were observed for γ-oryzanol.     

Effect of ectopic expression of homeoprotein EGAM1C on the cell morphology, growth, and differentiation in a mouse embryonic stem cell line, MG1.19 cells

The homeoprotein EGAM1C was identified in preimplantation mouse embryos and embryonic stem (ES) cells. To explore the impact of EGAM1C on the hallmarks of mouse ES cells, MG1.19 cells stably expressing EGAM1C at levels similar to those in blastocysts were established using an episomal expression system. In the presence of leukemia inhibitory factor (+LIF), control transfectants with an empty vector formed flattened cell colonies, while Egam1c transfectants formed compacted colonies with increased E-CADHERIN expression. In Egam1c transfectants, the cellular contents of POU5F1 (OCT4), SOX2, TBX3, and NANOG increased. Cell growth was accelerated in an undifferentiated state sustained by LIF and in the course of differentiation. During clonal proliferation, EGAM1C stabilized the undifferentiated state. In adherent culture conditions, EGAM1C partly inhibited the progression of differentiation at least within a 4-day culture period in the presence of retinoic acid by preventing the downregulation of LIF signaling with a robust increase in TBX3 expression. Conversely, EGAM1C enhanced the expression of lineage marker genes Fgf5 (epiblast), T (mesoderm), Gata6 (primitive endoderm), and Cdx2 (trophectoderm) in -LIF conditions. In embryoid bodies expressing EGAM1C, the expression of marker genes for extraembryonic cell lineages, including Tpbpa (spongiotrophoblast) and Plat (parietal endoderm), increased. These results demonstrated that the ectopic expression of EGAM1C is capable of affecting the stabilization of an undifferentiated state and the progression of differentiation in MG1.19 ES cells, in addition to affecting cellular morphology and growth.     

In Planta production of immunogenic poliovirus peptide using tobacco mosaic virus-based vector system

The tobacco mosaic virus (TMV) provides an attractive means of producing foreign peptides in plants. In this study, a TMV-based vector was designed such that a fragment encoding 15 amino acids of the poliovirus peptide (PVP) derived from the viral capsid proteins VP3 and VP1 of poliovirus type 1 Sabin was inserted downstream of the six-base 3' context nucleotide sequence of the TMV coat protein (CP) gene. This design allowed readthrough at the amber stop codon, thereby producing the chimeric TMV particle with both intact CP and CP-fusion protein (CP-PVP) in Nicotiana tabacum cv. Samsun infected with the TMV vector. The TMVCP-PVP virus particle induced antibodies against PVP as well as TMVCP in mice after intraperitoneal immunization. These data illustrate the potential of the readthrough translation system with TMVCP for antigen presentation and vaccine production.     

Phase inversion of particle-stabilized materials from foams to dry water

Small particles attached to liquid surfaces arise in many products and processes, including crude-oil emulsions and food foams and in flotation, and there is a revival of interest in studying their behaviour. Colloidal particles of suitable wettability adsorb strongly to liquid-liquid and liquid-vapour interfaces, and can be sole stabilizers of emulsions and foams, respectively. New materials, including colloidosomes, anisotropic particles and porous solids, have been prepared by assembling particles at such interfaces. Phase inversion of particle-stabilized emulsions from oil in water to water in oil can be achieved either by variation of the particle hydrophobicity (transitional) or by variation of the oil/water ratio (catastrophic). Here we describe the phase inversion of particle-stabilized air-water systems, from air-in-water foams to water-in-air powders and vice versa. This inversion can be driven either by a progressive change in silica-particle hydrophobicity at constant air/water ratio or by changing the air/water ratio at fixed particle wettability, and has not been observed in the corresponding systems stabilized by surfactants. The simplicity of the work is that this novel inversion is achieved in a single system. The resultant materials in which either air or water become encapsulated have potential applications in the food, pharmaceutical and cosmetics industries.     

Structure and Properties of Starch in Rice Double Mutants Lacking Starch Synthase (SS) IIa and Starch Branching Enzyme (BE) IIb

Starch biosynthetic enzymes form multi-protein complexes consisting of starch synthase (SS) I, SSIIa, and starch branching enzyme (BE) IIb, which synthesize amylopectin clusters. This study analyzed the starch properties in two double mutant rice lines lacking SSIIa and BEIIb, one of which expressed an inactive BEIIb protein. The ss2a be2b lines showed similar or greater seed weight than the be2b lines, and plant growth was not affected. The ss2a line showed increased short amylopectin chains resulting in a lower gelatinization temperature. Starch granule morphology and A-type crystallinity were similar between the ss2a line and the wild type, except for a mild chalky seed phenotype in the ss2a line. However, the starch phenotype of the ss2a be2b lines, which was similar to that of be2b but not ss2a, was characterized by increased long amylopectin chains, abnormal starch granules, and B-type crystallinity. The similarity in phenotype between the ss2a be2b and be2b lines may be attributed to the inability of the be2b mutants to generate short amylopectin branches, which serve as primers for SSIIa. Therefore, the presence or absence of SSIIa hardly affected the amylopectin structure under the be2b background. The amylose content was significantly higher in the ss2a be2b lines than in the be2b lines. Starch crystallinity was greater in ss2a be2b lines than in be2b lines, despite the fact that starch crystallinity is generally negatively correlated with amylose content. This suggests that the formation of a double helix between long amylopectin chains and amylose affects starch crystallinity in the ss2a be2b mutants.     

Walk control of segmented multi-legged robot based on integrative control of legs and 2-DoF active intersegment joints

This paper proposes a novel walk control method for multi-legged robots which have segmented bodies like a millipede. The segment of the robot which is addressed in this paper has a pair of legs which has 3 degrees of freedom (DoF) and 2-DoF active joint which connects the adjacent segmented body. The legs are controlled based on a decentralised control method, follow-the-contact point gait control, in which the legs contact on the contact-points where the forward legs have done. The joints between segments are controlled so as to make the bodies follow a desired trajectory. The legs and the intersegment joints are controlled with integrative and consistent manner thanks to local coordinate systems defined on each contact point. Finally, the proposed control method is verified via a robot simulator with physics engine.