The tridurylsilylium and tridurylstannylium cations: free and not so free.

Allyltridurylsilane has been prepared and converted to the tridurylsilylium cation by treatment with electrophiles. Allyltridurylstannane has been prepared and converted to the tridurylstannylium cation under similar conditions. The (29)Si chemical shift of the silylium cation indicates that it is free and tricoordinate, whereas the (119)Sn chemical shift of the stannylium cation indicates that it maintains loose fourth coordination with the solvent or the anion.

Voluntary intoxication and criminal responsibility.

This paper reviews the law related to voluntary intoxication and criminal responsibility in the 50 United States, the District of Columbia, the US Virgin islands, and Puerto Rico. Statutory and case law citations are provided which govern the use of intoxication evidence in each jurisdiction to negate mens rea (i.e., to establish diminished capacity), to support an insanity defense, and to mitigate criminal sentencing. Factors that courts typically focus on when deciding whether to admit this evidence in a particular case are discussed, and these factors are related to clinically relevant criteria.

Peer reviewed: x-ray photoelectron spectroscopy and archaeology.

XPS offers unique advantages for analyzing a wide range of artifacts.

Crystal structure of a silyl cation with no coordination to anion and distant coordination to solvent.

The crystal structure of a stable silyl cation, triethylsilylium, in the form of its tetrakis (pentafluorophenyl)borate salt [Et(3)Si(+) (C(6)F(5))(4)B(-)] (Et, ethyl) shows no coordination between cation and anion. The closest silicon-fluorine distance is greater than 4 angstroms. A toluene solvent molecule is close enough to cause some deviations from planarity at the silicon, but the silicon-toluene distance is well beyond the sum of the silicon and carbon covalent radii. The toluene molecule is essentially planar and undistorted, as expected if little or no positive charge has been transferred from silicon to toluene.

Rationalisation of therapy in severe epilepsy.

Anticonvulsant therapy in 18 institutionalised adult epileptic persons was rationalised. The mean number of drugs administered was reduced from 3.2 to 2.0 per patient with improvement of seizure control in 11 patients and either no alteration or a mild deterioration of seizure control in seven patients. In this latter group however, there was an improvement in cerebellar signs and/or mentation associated with the reduction in drug therapy. It is proposed that even in patients with apparently severe epilepsy, whilst monotherapy may not be achieved, a significant reduction in the number of medications administered may be. Moreover medication can be effectively administered twice daily.

Electron microprobe analysis of elemental distribution in excavated human femurs.

Elemental distributions have been determined for femur cross sections of eight individuals from the Gibson and Ledders Woodland sites. The analyses were obtained by x-ray fluorescence with a scanning electron microscope. Movement of an element from soil to bone should give rise to inhomogeneous distributions within the bone. We found that the distributions of zinc, strontium, and lead are homogeneous throughout the femur. In contrast, iron, aluminum, potassium, and manganese show clear buildup along the outer surface of the femur and sometimes along the inner (endosteal) surface, as the result of postmortem enrichment. The buildup penetrates 10-400 micron into the femur. The major elements calcium and sodium show homogeneous distributions, but considerable material could be lost by leaching (10-15%) without causing a palpable effect on the electron maps. Magnesium shows buildup on the outer edge of some samples. These results suggest that diagenetic contamination may exclude Fe, Al, K, Mn, and probably Mg from use as indicators of ancient data. The homogeneous distributions of Zn, Sr, and Pb suggest that these elements are not altered appreciably and may serve as useful dietary indicators.

Synthesis and action on the central nervous system of mescaline analogues containing piperazine or homopiperazine rings.

Structural juxtaposition of the 3,4,5-trimethoxyphenyl group in the same molecule with a piperazine or homopiperazine ring has been realized in a series of mescaline analogues (I-IV) as part of an investigation into the pharmacological properties of the seven-membered perhydro-1,4-diazepines (homopiperazines). The analogous six-membered piperazines were synthesized and tested as reference substances to determine whether the seven-membered ring conveyed special properties. A variety of pharmacological tests of action on the CNS showed that replacement of the amino group in mescaline by the heterocycles significantly alters the biological activity. In particular, both the piperazine and the homopiperazine derivatives displayed sedative activity to about the same extent.

A comparative study of the chemical analysis of ribs and femurs in Woodland populations.

Parallel chemical analyses of ribs and femurs from the Middle Woodland Gibson site and the Late Woodland Ledders site show that the elements most closely related to diet (strontium, zinc, magnesium) are found in identical proportions in the two bones. Elements associated with soil contamination (iron, aluminum, potassium, manganese) are found in a significantly higher proportion in the rib. The major elements calcium and sodium are found in lower levels in the ribs. Thus the rib is more sensitive to diagenetic processes that alter elemental proportions than is the femur. Conclusions concerning subgroupings by sex or site, derived from the diet-related elements (Sr, Zn, Mg), were found to be essentially the same for the rib and the femur.

Carbon functionalities in amber.

High-resolution nuclear magnetic resonance spectra of the carbon nuclei in powdered amber, obtained by using the techniques of magic angle spinning and cross polarization, provide detailed information about the types of carbon functionalities. The entire spectrum of Baltic amber (succinite) is identical for several samples. Baltic amber shows minor differences from Sicilian amber and drastic differences from Burmese, Romanian, and Bohemian ambers.