SIR,-Dr Weitz and colleagues (April 20, p 933) report the value of breath pentane analysis as an index of increased lipid peroxidation in vivo. However, Weitz et al fail to indicate the potential shortcomings of the method, as we are beginning to see in the context of cystic fibrosis. We have found that techniques involving hydrocarboncontaminated inspired air, as used by Weitz et al, produce u...

In each of the two independent indene-4-spiro-pentane mol-ecules in the asymmetric unit of the title 2:1 adduct, C(19)H(18)N(6)·0.5C(5)H(4)OS, the cyclo-hexene ring adopts a half-chair conformation and the cyclo-pentene and cyclo-pentane rings adopt envelope conformations. The mean plane through the cyclo-hexene/cyclo-pentene fused system is aligned at a dihedral angle of 77.9 (1)° with respect...

The title compound, [Zr2(C10H15)4(C6H6N2)2]·C6H14, was obtained by the stoichiometric reaction of adipo-nitrile with [Zr(C10H15)2(η(2)-Me3SiC2SiMe3)]. Intra-molecular nitrile-nitrile couplings and deprotonation of the substrate produced the (1-imino-2-enimino)-cyclo-pentane ligand, which functions as a five-membered bridge between the two metal atoms. The Zr(IV) atom exhibits a distorted tetra-...

The title compound, poly[[di-aqua-bis-[1,5-bis-(pyridin-4-yl)pentane-κ(2) N:N']cadmium] bis-(perchlorate) 1,5-bis-(pyridin-4-yl)pentane ethanol mono-solvate], [Cd(C15H18N2)2(H2O)2](ClO4)2·C15H18N2·C2H6O, is a layered coordination polymer built up from highly squashed 4(4) nets in which the octa-hedral trans-CdO2N4 nodes (Cd site symmetry -1) are linked by the bifunctional ligands, forming infin...

Catalytic isomerization of glucose to fructose by immobilized glucose isomerase in an aqueous-ethanol medium was studied. Using Michaelis-Menten equation and Haldane relationship, the main kinetic parameters were determined: Kmf, Vmf, Kmr, Vmr. By comparing the aqueous-ethanol medium with an aqueous solution, the measured values of Kmr and Kmf were increased in the aqueous-ethanol solution, whi...

The relationship between the bulk density and pressure of configurations corresponding to local minima on the potential energy surface of molecular models of ethane, n-pentane, and cyclopentane ~the equation of state of their energy landscape! has been explored. Like simpler, atomic fluids, these systems exhibit a limiting bulk density below which minimum energy configurations are no longer spa...

A volatile profile of ramson (wild garlic, Allium ursinum L.) honey was investigated by headspace solid-phase microextraction (HS-SPME) and ultrasonic solvent extraction (USE) followed by gas chromatography and mass spectrometry (GC-FID/GC-MS) analyses. The headspace was dominated by linalool derivatives: cis- and trans-linalool oxides (25.3%; 9.2%), hotrienol (12.7%), and linalool (5.8%). Besi...

We study pentane depletion using a hybrid plasma system based on surface dielectric barrier discharge (SDBD), with and without catalyst, as function of power alkane concentration. evaluate decomposition efficiency quantify the role catalyst in resulting intermediate products. Analyses temporal evolution products allow us to estimate corresponding rates according parameters. find that increases ...

Membrane environment and fluidity can modulate the dynamics and interactions of membrane proteins and can thereby strongly influence the function of cells and organisms in general. In this work, we demonstrate that trans-cis isomerization of lipophilic dyes is a useful parameter to monitor packaging and fluidity of biomembranes. Fluorescence fluctuations, generated by trans-cis isomerization of...