The alignment of nematic liquid crystals on photolithographic micro-groove patterns

The alignment of nematic liquid crystals on micro-groove patterns was studied. It has been found that the order of the alignments is determined by the edge shape, spacing, and line pitch of the micro-groove patterns. On coarse patterns, with pitches greater than 2 μm, striped patterns of the liquid crystal alignment were observed using polarized light which manifested different orientations of the liquid crystals on the top, edge, and bottom of the grooves, respectively. On fine patterns, with pitches less than 2 μm, a uniform device-quality alignment has been realized, with which twisted nematic cells were constructed in combination with the rubbed alignment layer on the opposite substrate. Their viewing angle characteristics and tilt orientations of the director were also investigated.     

Minimal subschemes of the group association schemes of Mathieu groups

Minimal subschemes of the group association schemes of Mathieu groupsM _n (n = 11, 12, 22, 23, 24) are determined. It is proved that for eachM _n (n = 11, 12, 22, 23, 24), there is a unique minimal subscheme of. The class numbers of these minimal subschemes are 7, 11, 9, 11 and 20 respectively. A general computer program to determine subschemes of group association schemes of relatively small class numbers is discussd.     

‘Effective hot reaction zone’, caging energy and normalized appearance energy in ruthenium complexes

In contrast to the single molecule cage of Ru/acac/₃ a cage involving wall molecules of RuCp₂ is formed in recoil reaction of radioruthenium atoms. Enhancement of the parent yield in RuCp₂ is ascribed to the larger size of the cage /effective hot reaction zone/ compared to the case of Ru/acac/₃. A normalized appearance energy technique has been applied to estimate energy /AE _adj ^x / necessary for caging the recoil atom in RuCp₂. AE _adj ^x is about twice as large as caging energy CE. The relation of AE _adj ^x to CE in RuCp₂ is nearly the same as that of AE^x to bonding energy BE in Ru/acac/₃.     

Agelasine-E and -F,novel monocyclic diterpenoids with 9-methyladeninium unit possessing inhibitory effects on Na,K-ATPase isolated from the Okinawan sea sponge Agelas nakamurai Hoshino

Agelasine-E and -F, novel terpenoids with a 9-methyladeninium unit have been isolated from the orange colored sea sponge $\text{Agelas nakamurai}$ Hoshino as Na,k-ATPase inhibitors and their structures and absolute configurations have been determined on the basis of spectral data and chemical conversions.     

Transverse plasmon in two-dimensional electrons

We calculated the retarded transverse current-current response function of an ideal two-dimensional electron gas and obtained a dispersion relation for the transverse plasmon in the system.     

Electrostatic force acting on conductive ball between electrodes II: Cylindrical upper electrode with hemispherical tip for capturing/releasing conductive ball

The electrostatic force between a conductive ball on a plane electrode and a cylindrical electrode with a hemispherical tip is analyzed. A cylindrical electrode with a dielectric film for realizing a new LSI bonding system is proposed. The force on the ball increases with increasing diameter of the cylindrical electrode. When a dielectric film is placed under the cylindrical upper electrode with a fixed gap between the electrodes, the force acting on the ball increases with increasing dielectric film thickness. Capture of the ball was experimentally confirmed. This study provides a useful foundation for electrostatic manipulation of a conductive ball.     

Shuffle products for multiple zeta values and partial fraction decompositions of zeta-functions of root systems

The shuffle product plays an important role in the study of multiple zeta values (MZVs). This is expressed in terms of multiple integrals, and also as a product in a certain non-commutative polynomial algebra over the rationals in two indeterminates. In this paper, we give a new interpretation of the shuffle product. In fact, we prove that the procedure of shuffle products essentially coincides with that of partial fraction decompositions of MZVs of root systems. As an application, we give a proof of extended double shuffle relations without using Drinfel??d integral expressions for MZVs. Furthermore, our argument enables us to give some functional relations which include double shuffle relations.     

Rapid determination of glyphosate, glufosinate, bialaphos, and their major metabolites in serum by liquid chromatography-tandem mass spectrometry using hydrophilic interaction chromatography

We developed a simple and rapid method for the simultaneous determination of phosphorus-containing amino acid herbicides (glyphosate, glufosinate, bialaphos) and their major metabolites, aminomethylphosphonic acid (AMPA) and 3-methylphosphinicopropionic acid (MPPA), in human serum. Serum samples were filtrated through an ultrafiltration membrane to remove proteins. The filtrate was then washed with chloroform, and injected into a liquid chromatography-tandem mass spectrometry (LC-MS/MS) system. Chromatographic separation was achieved on a hydrophilic interaction chromatography (HILIC) column. Determination of the target herbicides and metabolites was successfully carried out without derivatization or solid phase extraction (SPE) cartridge clean-up. The recoveries of these compounds, added to human serum at 0.2μg/mL, ranged from 94% to 108%, and the relative standard deviations (RSDs) were within 5.9%. The limits of detection (LODs) were 0.01μg/mL for MPPA, 0.02μg/mL for AMPA, 0.03μg/mL for both glyphosate and glufosinate, and 0.07μg/mL for bialaphos, respectively.     

Synthesis of 2'-O-[2-(N-methylcarbamoyl)ethyl]ribonucleosides using oxa-Michael reaction and chemical and biological properties of oligonucleotide derivatives incorporating these modified ribonucleosides

To develop oligonucleotides containing new 2'-O-modified ribonucleosides as nucleic acid drugs, we synthesized three types of ribonucleoside derivatives modified at the 2'-hydroxyl group with 2-(methoxycarbonyl)ethyl (MOCE), 2-(N-methylcarbamoyl)ethyl (MCE), and 2-(N,N-dimethylcarbamoyl)ethyl (DMCE) groups, as key intermediates, via the oxa-Michael reaction of the appropriately protected ribonucleoside (U, C, A, and G) derivatives. Among them, the 2'-O-MCE ribonucleosides were found to be the most stable under basic conditions. To study the effects of the 2'-O-modification on the nuclease resistance of oligonucleotides incorporating the 2'-O-modified ribonucleosides and their hybridization affinities for the complementary RNA and DNA strands, 2'-O-MCE-ribonucleoside phosphoramidite derivatives were successfully synthesized and subjected to the synthesis of 2'-O-MCE-oligonucleotides and 2'-O-methyl-oligonucleotides incorporating 2'-O-MCE-ribonucleosides. The 2'-O-MCE-oligonucleotides and chimeric oligomers with 2'-O-MCE and 2'-O-methyl groups thus obtained demonstrated complementary RNA strands and much higher nuclease resistances than the corresponding 2'-O-methylated species. Finally, we incorporated the 2'-O-MCE-ribonucleosides into antisense 2'-O-methyl-oligoribonucleotides to examine their exon-skipping activities in splicing reactions related to pre-mRNA of mouse dystrophin. The exon-skipping assay of these 2'-O-methyl-oligonucleotide incorporating 2'-O-MCE-uridines showed better efficacies than the corresponding 2'-O-methylated oligoribonucleotide phosphorothioate derivatives.     

Thermogelation of amphiphilic poly(asparagine) derivatives

Thermoresponsive sol–gel transition polymers based on biodegradable poly(amino acid) were synthesized by the reaction of poly(succinimide) with dodecylamine and amino alcohols. The introduction of the hydrophobic amine into the thermoresponsive poly(amino acid)s induced the sol–gel transition in phosphate buffer saline. The effects of the side chain structure, molecular weight, concentration of the polymer, and the additives (inorganic salts and urea) in the solution on the thermoresponsive behaviors were systematically investigated. A relationship between the lowest critical solution temperature (LCST) in the dilute solution and the viscosity reduction of the concentrated solution upon heating was observed. The present poly(amino acid)s showing a thermoresponsive sol–gel transition in aqueous solutions possess immense potential as an injectable biodegradable hydrogel system for various biomedical applications. Copyright © 2009 John Wiley & Sons, Ltd.