Biomedical subjects

R Ayer

Publications and source records attributed to R Ayer.

3 recordsLinked to original sources

PubMed2005

Complex pediatric elbow injury: an uncommon case.

BACKGROUND: There is paucity of literature describing complex elbow trauma in the pediatric population. We described a case of an uncommon pediatric elbow injury comprised of lateral condyle fracture associated with posterolateral dislocation of elbow. CASE PRESENTATION: A 12-year-old boy sustained a direct elbow trauma and presented with Milch type II lateral condyle fracture associated with posterolateral dislocation of elbow. Elbow dislocation was managed by closed reduction. The elbow stability was assessed under general anaesthesia, followed by open K-wiring for the lateral condylar fracture fixation. The patient had an uneventful recovery with an excellent outcome at 39 months follow-up. CONCLUSION: Complex pediatric elbow injuries are quite unusual to encounter, the management of such fractures can be technically demanding. Concomitant elbow dislocation should be managed by closed reduction followed by open reduction and internal fixation (K-wires or cannulated screws) of the lateral condyle fracture.

Bone Wires↗

PubMed1989

Determination of unit cell.

The ability to obtain diffraction patterns with a large angular view has significantly enhanced the ease and potential of electron diffraction studies in the determination of unit cells and identification of submicron phases. Convergent beam electron diffraction (CBED) provides a two-dimensional projection of the three-dimensional reciprocal lattice and can be utilized to reconstruct the unit cell dimensions. In particular, the spacing of the reciprocal lattice layers parallel to the electron beam and the location and distribution of the reflections in the first and higher order Laue zones with respect to the zero layer provide information which cannot be obtained from the zero layer pattern alone. This additional information permits the identification of crystal structures of phases under investigation with previously established ones or the determination of a new structure, if previously unknown. The article describes the principles of the analysis and illustrates the application of the methods with examples from commercial material systems.

Crystallography↗

PubMed1989

Characterization of the larval olfactory response in Drosophila and its genetic basis.

Drosophila larvae are attracted to a wide variety of chemical stimuli. The olfactory response to ethyl acetate, a powerful attractant, was found to be surprisingly well conserved across a variety of different wild-type strains. Strain differences are documented, however, both in attraction to ethyl acetate and in another chemosensory behavior: avoidance of an aversive stimulus. As a means of analyzing the extent of genetic heterogeneity within strains, one wild-type population, Canton-S, was screened for variant X chromosomes. An enrichment procedure was characterized and used to make the screening more efficient. Lines homozygous for individual X chromosomes were established, and all were found to exhibit a strong olfactory response, although evidence was found for variation among them. The olfactory response was found to be conserved through an extended period of larval development, including the final period during which larvae leave the culture medium in preparation for metamorphosis. The results are discussed in terms of the genetic basis of the response and the use of single-gene mutations as a means of dissecting olfactory system function.

Animals↗