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Adams–Oliver syndrome (AOS) is a rare disease characterized by congenital scalp defects, terminal transverse limb defects and cutis marmorata telangiectatica. A significant incidence of cardiac and vascular malformations has been reported, leading to the hypothesis of a vascular defect early involved in the pathogenesis. We report two members of the same family with previously diagnosed AOS based on clinical phenotype and later recognized to have pulmonary arterio‐venous malformation (PAVM). None of the subjects fulfilled current diagnostic criteria of hereditary hemorrhagic telangiectasia, which is the most common cause of PAVM. The occurrence of PAVM in AOS lends support to the hypothesis that endothelial specific abnormalities could be a patho‐physiological mechanism in its development. Therefore, the role of screening for PAVM in clinical management of subjects with AOS should deserve further studies. © 2005 Wiley‐Liss, Inc.

This paper reviews the main achievements of the Targeted Project “Special Materials for Advanced Technology” (TP SMAT [1989–1993]).

A Lifson-Warshel force field of the type recently used by the authors to study defect structures in silicon has now been developed for diamond. The parameters of this field are determined mostly by least-squares fitting of the phonon dispersion curves, but some experimental values must also be used. The crucial term is the torsional parameter, for which values differing by a factor of two or so have been proposed, leading to stacking-fault energies ranging from 992 to 340 mJ m-2. The latter value derives from a better-based value of the torsional parameter and agrees well with a recent experimental value of 279 ± 41 mJ m-2. The possibility of lattice relaxation in the stacking fault is also discussed.

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The core structure of the reconstructed 90° partial dislocation in silicon is obtained by energy minimization with respect to the Lifson - Warshel valence force field using periodic boundary conditions. A low strain energy attests to the stability of the reconstructed geometry. The electronic structure is calculated using a local pseudo-potential approach in an improved peripheral orbital treatment. The silicon indirect gap is found to be completely clear of dislocation levels, in agreement with experiment. Stacking-fault levels are found in the gap near the valence band edge in agreement with specialized stacking-fault energy level calculations.

The core structure of the 90° partial dislocation in silicon is obtained by energy minimization of a cluster with respect to a Lifson-Warshel valence force field. Both the reconstructed and unreconstructed topologies are considered, and the reconstructed structure is favoured by 2·66 eV per lattice vector. Comparison of these structures with the one resulting from the anisotropic elastic approximation shows that the latter introduces a spurious bond length alternation. Electronic dislocation bands are determined by the extended Hückel theory, the parameters of which are obtained by calculation and fitting of the perfect silicon lattice. For the reconstructed structure, the lower dislocation band dips by more than 1 eV below the top of the valence band (Ev) and the upper band - unoccupied, of width 1·2 eV - lies in the gap, extending from about 0·4eV above Ev until it overlaps the bottom of the conduction band. Comparison of the bands for the elastic and unreconstructed structures indicates that the spurious bond length alternation of the elastic structure pulls the lower dislocation band over Ev.

The results of EHT calculations on the most stable conformations of the neurotransmitter molecule acetylcholine (ACh) are reported. These results are compared with those obtained with other semiempirical quantum mechanical methods CNDO/2, INDO and PCILO, and with those obtained by the classical partitioning of the energy method (PEM). From this comparison it becomes evident a wide agreement between the results of PCILO, EHT and PEM, all these methods allowing accessibility to discrete regions in conformational space.