Preparation of 1-hydroxyethyl-2-trideuteriomethyl-5-nitroimidazole

The title compound was prepared by two different procedures. The first route starts with acetonitrile-d₃ and goes through 2-trideuteriomethyl-5-nitroimidazole ( 6 ) (Scheme I). The second and more convenient process is direct labeling of metronidazole ( 1 ) with alkaline ethanol-d₁.     

Synthetic hologram made by variable magnification imaging system

For the purpose of improving the utilization efficiency of the gain bandwidth of active media and generating stable ultrashort light pulses, a passive-active mode locking technique has been applied to a cw Rhodamine 6G dye laser. A sufficient ability of this technique for the elimination of the multiple-pulse operation of the mode locking at a higher pumping level and a longer resonator length has been proved. Observed pulse-width by the SHG autocorrelation technique is 1.4 ps with assuming a sech² pulse profile.     

Facile synthesis of thiacalix[n]arenes (n=4, 6, and 8) consisting of p-tert-butylphenol and methylene/sulfide alternating linkage and metal-binding property of the n=4 homologue

2,14-Dithiacalix[4]arene 3₄ was conveniently prepared in 16% yield by acid-catalyzed cyclocondensation of 2,2^′-thiobis[4-tert-butylphenol] with formaldehyde. The present method also afforded the first isolation of the analogues with six and eight phenol units, 3₆ (10%) and 3₈ (5%), respectively. Solvent extraction showed that 3₄ had high selectivity toward Cu²⁺ ion at pH 5.5 by coordination of the bridging sulfur with cooperative donation of the adjacent phenolate oxygens.     

Smell and Stress Response in the Brain: Review of the Connection between Chemistry and Neuropharmacology

The stress response in the brain is not fully understood, although stress is one of the risk factors for developing mental disorders. On the other hand, the stimulation of the olfactory system can influence stress levels, and a certain smell has been empirically known to have a stress-suppressing effect, indeed. In this review, we first outline what stress is and previous studies on stress-responsive biomarkers (stress markers) in the brain. Subsequently, we confirm the olfactory system and review previous studies on the relationship between smell and stress response by species, such as humans, rats, and mice. Numerous studies demonstrated the stress-suppressing effects of aroma. There are also investigations showing the effects of odor that induce stress in experimental animals. In addition, we introduce recent studies on the effects of aroma of coffee beans and essential oils, such as lavender, cypress, α-pinene, and thyme linalool on the behavior and the expression of stress marker candidates in the brain. The transfer of volatile components into the brain is also discussed while using the results of thyme linalool as an example. These studies may provide a good opportunity to connect chemical research at the molecular level with neuropharmacological approaches in the future.     

Photoviscoelastic analysis of thermal stress in a quenched epoxy beam

This paper reports on a procedure for photoviscoelastic analysis where the axes of principal stress, principal strain and polarization of light coincide in the presence of a large temperature change. More specially, the transient-thermal stress and strain due to stress in an epoxy beam subjected to quenching from both the upper and lower surfaces, are determined using the time-temperature-equivalent law for stress, strain and birefringence. The transient-thermal stress and strain in the beam were determined experimentally using hereditary integrations from the measurement of the transient temperature and birefringence due to the quenching of the beam. The transient thermal stress and strain were also calculated theoretically using the linear-viscoelastic theory. The experimentally determined thermal stress agrees closely with the theoretical results. The experimentally determined strain agrees qualitatively with the theoretical values. Thus, it is concluded that the photoviscoelastic technique is useful in analyzing the proposed problem.Paper was presented at 1982 SESA/JSME Spring Meeting held in Maui and Oahu, HI on May 23–28, 1982.