Sex Attractant Pheromone from the Rice Stalk Stink Bug, Tibraca limbativentris Stal

The male-produced sex pheromone from the Brazilian rice stalk stink bug Tibraca limbativentris is reported. Olfactometer bioassays with sexually mature males and females showed that males attracted females, which suggests that males release a sex pheromone. Males were not attracted to either sex, nor were females attractive to conspecific females. Attraction of the females to males was highest at night. The headspace volatiles collected from male and female bugs were analyzed by gas chromatography (GC) and GC–mass spectrometry. Two male-specific compounds were identified as isomers of 1′S-zingiberenol, whereas a series of defensive compounds were identified in extracts from both sexes. Zingiberenol has three chiral centers, and the nonselective syntheses used produced two groups of isomers, zingiberenol I containing four isomers, namely (1RS,4RS,1′R)-4-(1′,5′-dimethylhex-4′-enyl)-1-methylcyclohex-2-en-1-ol, and zingiberenol II containing the other four isomers, namely (1RS,4RS,1′S)-4-(1′,5′-dimethylhex-4′-enyl)-1-methylcyclohex-2-en-1-ol. Both groups of stereoisomers were more attractive than hexane controls. The absolute configuration of the insect-produced pheromonal components remains to be elucidated, but the 1′S stereochemistry was established for at least one of the isomers.     

High-precision temperature control and stabilization using a cryocooler

We describe a method for precisely controlling temperature using a Gifford-McMahon (GM) cryocooler that involves inserting fiber-reinforced-plastic dampers into a conventional cryosystem. Temperature fluctuations in a GM cryocooler without a large heat bath or a stainless-steel damper at 4.2 K are typically of the order of 200 mK. It is particularly difficult to control the temperature of a GM cryocooler at low temperatures. The fiber-reinforced-plastic dampers enabled us to dramatically reduce temperature fluctuations at low temperatures. A standard deviation of the temperature fluctuations of 0.21 mK could be achieved when the temperature was controlled at 4.200?0 K using a feedback temperature control system with two heaters. Adding the dampers increased the minimum achievable temperature from 3.2 to 3.3 K. Precise temperature control between 4.200?0 and 300.000 K was attained using the GM cryocooler, and the standard deviation of the temperature fluctuations was less than 1.2 mK even at 300 K. This technique makes it possible to control and stabilize the temperature using a GM cryocooler.     

Effects of sulfated fucan,ascophyllan, from the brown Alga Ascophyllum nodosum on various cell lines: A comparative study on ascophyllan and fucoidan

The effects of fucose-containing sulfated polysaccharides, ascophyllan and fucoidan, isolated from the brown alga Ascophyllum nodosum, on the growth of various cell lines (MDCK, Vero, PtK₁, CHO, HeLa, and XC) were investigated. In a colony formation assay, ascophyllan and fucoidan showed potent cytotoxic effects on Vero and XC cells, while other cell lines were relatively resistant to these polysaccharides. Almost no significant effects of these polysaccharides were observed in the cell lines tested using the Alamar blue cytotoxicity assay over 48 h with varying initial cell densities (2500–20,000 cells/well) in growth medium. Interestingly, a significant growth promoting effect of ascophyllan on MDCK cells was observed, whereas treatment with fucoidan showed growth suppressive effects on this cell line under the same experimental conditions. These results suggest that ascophyllan is distinguishable from fucoidan in terms of their bioactivities. This is the first report of the growth promoting effects of a sulfated fucan on a mammalian cell line under normal growth conditions.     

Size Controlled Synthesis of Gold Nanoparticles by Porphyrin with Four Sulfur Atoms

Tetradentate thioacetyl porphyrin ligand (1) was synthesized to protect gold nanoparticles. 1-protected gold nanoparticles were characterized by UV-vis spectroscopy and XPS. Analysis by XPS showed that all of four thioacetyl groups of 1 were dissociated and bound to the surface of gold nanoparticles in thiolate form. The size of 1-protected gold nanoparticles (GN:1) was controlled by thioacetyl group/HAuCl₄ molar ratio and approached to 2 nm. Compared with a protecting ligand without porphyrin plane (2) or dodecanethiol, 1 can control the size of gold nanoparticles efficiently probably due to the tetradentate ligation effect.     

Catalytic dehydration of 1,2-propanediol into propanal

Vapor-phase catalytic dehydration of 1,2-propanediol was investigated over several catalysts, such as acidic oxides and supported heteropoly acids. These acids catalyze the dehydration of 1,2-propanediol to produce propanal. In particular, silica-supported silicotungstic acid showed the highest catalytic activity in the formation of propanal. At low conversions, however, propanal reacted with another 1,2-propanediol to produce a cyclic acetal (2-ethyl-4-methyl-1,3-dioxolane). Such acetal formation reduced the selectivity to propanal. Under optimum reaction conditions, 100% conversion was attained with propanal selectivity higher than 93 mol% at 200 °C.     

MR perfusion imaging by alternate slab width inversion recovery arterial spin labeling (AIRASL): a technique with higher signal-to-noise ratio at 3.0?T

Object  

To propose a new arterial spin labeling (ASL) perfusion-imaging method (alternate slab width inversion recovery ASL: AIRASL) that takes advantage of the qualities of 3.0 T.     

Aerobic Alcohol Oxidation by Ruthenium Species Stabilized on Nanocrystalline Magnesium Oxide by Basic Ionic Liquids

The selective oxidation of various alcohols into their corresponding aldehydes and ketones was achieved by ruthenium species stabilized on the nanocrystalline magnesium oxide (NAP‐MgO) by the incorporation of choline hydroxide, a basic ionic liquid, in excellent yields. The procedure is simple, efficient and environmentally benign. The catalyst can be used for four cycles with almost consistent activity.     

Niobium‐Catalyzed Highly Enantioselective Aza‐Diels–Alder Reactions

Niobium‐based chiral Lewis acid was found to be highly effective catalyst for aza‐Diels–Alder reactions of imines with Danishefsky‘s dienes. The reactions proceed in high yield with high enantioselectivity for both aromatic and aliphatic imines. The developed methodology was applied to total synthesis of (+)‐anabasine.     

Development of an Artificial Lipid-Based Membrane Sensor with High Selectivity and Sensitivity to the Bitterness of Drugs and with High Correlation with Sensory Score

This paper reports the development of membrane sensors based on an artificial lipid and plasticizers with high selectivity and sensitivity to drug bitterness by using bis(1-butylpentyl) adipate (BBPA), bis(2-ethylhexyl) sebacate (BEHS), phosphoric acid tris(2-ethylhexyl) ester (PTEH), and tributyl o-acetylcitrate (TBAC) as a plasticizer and phosphoric acid di-n-decyl ester (PADE) as an artificial lipid to optimize surface hydrophobicity of the sensors. In addition, a sensor with highly correlated bitterness sensory score was developed by blending BBPA and TBAC to detect the bitterness suppression effect of sucrose, and other bitter-masking materials. Therefore, this sensor can be used to evaluate the bitterness of various drug formulations with high accuracy. Copyright © 2009 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.