HABITUATION OF SLEEP TO ROAD TRAFFIC NOISE OBSERVED NOT BY POLYGRAPHY BUT BY PERCEPTION

The habituation of sleep to road traffic noise was investigated. Habituation of sleep is improvement of sleep quality. Nine male students aged 19-21 were exposed to tape-recorded road traffic noise ofL_eq 49·6 dB(A) in an experimental bedroom. Among 17 nights, the first four and the last three nights were non-exposure nights and the other consecutive 10 were exposure nights. The polygraphic sleep parameters were: sleep stages S1, S2, S(3+4), rapid eye movements (REM), and so on. Subjective sleep quality was assessed by five scales of a self-rating sleep questionnaire named the OSA, sleepiness (F1), sleep maintenance (F2), worry (F3), integrated sleep feeling (F4), and sleep initiation (F5). In this experiment, the habituation of sleep to road traffic noise was observed clearly in all of the subjective sleep parameters of the OSA, though all of the polygraphic sleep parameters showed little or no evidence of habituation. This suggests that habituation to noise has two aspects, sensation and perception mechanisms, corresponding to sleep polygraphy and to questionnaire respectively.     

Thermal/hyperbaric heterocycloaddition of 1,4-dialkoxy-1,3-dienes: the de novo (E,Z) way to sugars

1-(Z)-Alkoxy-4-(E)-methoxybutadiene derivatives have been reacted with ethylgyoxylate and diethyl ketomalonate under thermal or hyperbaric conditions. They provide, with a total regioselectivity and fair to total endoselectivities, the expected dihydropyranic cycloadducts. Three of those pseudo-glycals have been converted in a few classical steps (deprotection, reduction, and dihydroxylation) into (racemic) allose, mannose, and gullose derivatives. The order of these three steps has a direct influence on the efficiency of the transformation and determines the stereochemistry of the final sugar.     

Structure Analysis of Montmorillonite Intercalated with Cetylpyridinium and Cetyltrimethylammonium: Molecular Simulations and XRD Analysis

Molecular mechanics and molecular dynamics simulations combined with X-ray powder diffraction were used in structure investigation of montmorillonite intercalated with cetylpyridinium (CP) and cethyltrimethylammonium (CTA) cations. Molecular modeling revealed the interlayer structure and differences in intercalation behavior of CP and CTA cations in montmorillonite. The experimental and calculated values of basal spacing were in good agreement for both intercalates: in the case of CP-montmorillonite d(exp)=20.59 ?, d(calc)=20.60 ?; for CTA-montmorillonite d(exp)=18.00 ? and d(calc)=18.10 ?. CTA-montmorillonite exhibits significantly higher total sublimation energy and higher host-guest interaction energy than the CP-montmorillonite. The main difference between both intercalates is in charge distribution on the host layers and guest species. The charge transfer from the guest species to the host layer is higher in CTA-montmorillonite than in CP-montmorillonite, and consequently the charge polarization between the host and guest layers is much higher in CTA-montmorillonite. This leads to much stronger host-guest electrostatic interaction in the case of CTA-montmorillonite. Copyright 2001 Academic Press.     

Obtention d'alkoxy-2 cyano-3 2H chromènes

2-Alkoxy-3-cyano-2H-chromenes were prepared by the action of an alcohol on 2-morpholino-3-cyano-2H-chromenes in the presence of hydrochloric acid.     

Proportional counters for Mössbauer spectroscopy

The problem of ψ-ray detection by using proportional counters for Mössbauer effect spectroscopy has been studied. The investigations on the constructional solutions of proportional counters and filling gas mixtures have been worked out. Some measurement geometries using proportional counters have been proposed. The obtained results allow to improve signal to noise ratio as well as the detection stability.     

Normal growth of large groups

For a finitely generated group $\Gamma$, denote by the number of normal subgroups of index n. A. Lubotzky proved that for the free group F_r of rank r, is of type n^logn. We show that the same is true for a much larger class of groups. On the other hand we show that for almost all n, the inequality < holds true for every r-generated group $\Gamma$.Received: 30 October 2002     

Characterization of human alcohol dehydrogenase isoenzymes by capillary isoelectric focusing-mass spectrometry

The human liver alcohol dehydrogenase (ADH) isoenzymes are currently believed to play a major role in ethanol metabolism, accounting for most of the ethanol oxidized in the liver. They have similar molecular masses and similar isoelectric point (pI) values (the 13 possible isoenzymes having pIs in the range of 8.26-8.87), making their characterization a significant analytical challenge. Capillary isoelectric focusing (CIEF) coupled on-line with electrospray ionization - Fourier transform ion cyclotron resonance (ESI-FTICR) mass spectrometry was applied to separate and characterize mixtures of alphaalpha, beta1beta1 and beta3beta3 ADH isoenzymes. Seven different species were resolved by the separation in the pI 8.26-8.67 range. ESI-FTICR analysis of native ADHs revealed that each noncovalent ADH complex contains two monomeric protein units and four zinc atoms. The combination of CIEF separations with mass spectrometry appears well-suited for detailed characterization of ADH isozymes, and the attomole level sensitivity of FTICR should allow very small samples to be addressed.