Biomedical subjects

Henning Meyer

Publications and source records attributed to Henning Meyer.

3 recordsLinked to original sources

PubMed2006

Electronic spectroscopy of the 3d Rydberg states of NO-Rg (Rg=Ne,Ar,Kr,Xe) van der Waals complexes.

We have employed (2+1) resonance-enhanced multiphoton ionization spectroscopy to record electronic absorption spectra of NO-Rg (Rg=Ne,Ar,Kr) van der Waals complexes. The nitric oxide molecule is the chromophore, and the excitation corresponds to an electron being promoted from the 2ppi* orbital to 3dsigma, 3dpi, and 3ddelta Rydberg states. We review the ordering of the 3dlambda states of NO and use this as a basis for discussing the 3d components in the NO-Rg complexes, in terms of the interactions between the Rydberg electron, the core, and the Rg atom. Predissociation of the H' 2Pi state occurs through the F2Delta state for NO-Ar and NO-Kr, and this will be considered. We shall also outline problems encountered when trying to record similar spectra for NO-Xe, related to the presence of atomic Xe resonances.

Journal Article↗

PubMed2002

Complications of plate fixation in metacarpal fractures.

BACKGROUND: The objective of this study is to assess the complications after open reduction and plate fixation of extra-articular metacarpal fractures. METHODS: We retrospectively reviewed the clinical and radiologic records of 129 consecutive patients with 157 metacarpal fractures treated by open reduction and internal fixation with plates between 1993 and 1999. Intra-articular fractures and fractures of the thumb metacarpal were excluded. Eighty-one patients (64 men and 17 women) with 104 fractures were available for review, at an average follow-up of 13.6 months (range, 6-27 months). RESULTS: Twenty-eight patients (35%) and 33 fractures (32%) had one or more complications, including difficulty with fracture healing (12 patients [15%]), stiffness (eight patients [10%]), plate loosening or breakage (seven patients [8%]), complex regional pain syndrome (two patients), and one patient who developed a deep infection. CONCLUSION: Despite technical advances in implant material, design, and instrumentation, plate fixation of metacarpal fractures remains fraught with complications and unsatisfactory results.

Adolescent↗

PubMed2001

The molecular Hamiltonian.

The molecular Hamiltonian represents one of the most basic concepts in spectroscopy and molecular reaction dynamics. Its derivation is notoriously difficult owing to the use of a rotating reference frame which, in turn, is necessary to define the concept of vibration and rotation. In this article, we review the construction of the molecular Hamiltonian in normal mode and in internal coordinates. For normal mode coordinates, the Watson Hamiltonian including its modification for linear molecules is derived using an approach based on classical mechanics and the Podolsky transformation. The method is subsequently used to derive the molecular Hamiltonian in terms of Jacobi and valence coordinates. Results are presented for the triatomic system and for the extension toward N-atom systems with N > or = 3.

Journal Article↗