Representation theoretic patterns in three dimensional Cryo-Electron Microscopy I: The intrinsic reconstitution algorithm

In this paper, we reveal the formal algebraic structure underlying the intrinsic reconstitution algorithm, introduced by Singer and Shkolnisky in [9], for determining three dimensional macromolecular structures from images obtained by an electron microscope. Inspecting this algebraic structure, we obtain a conceptual explanation for the admissibility (correctness) of the algorithm and a proof of its numerical stability. In addition, we explain how the various numerical observations reported in that work follow from basic representation theoretic principles

Management of giant pseudomeningoceles after spinal surgery

<p>Abstract</p> <p>Background</p> <p>Pseudomeningoceles are a rare complication after spinal surgery, and studies on these complex formations are few.</p> <p>Methods</p> <p>Between October 2000 and March 2008, 11 patients who developed symptomatic pseudomeningoceles after spinal surgery were recruited. In this retrospective study, we reported our experiences in the management of these complex, symptomatic pseudomeningoceles after spinal surgery. A giant pseudomeningocele was defined as a pseudomeningocele >8 cm in length. We also evaluated the risk factors for the formation of giant pseudomeningoceles.</p> <p>Results</p> <p>All patients were treated successfully with a combined treatment protocol of open revision surgery for extirpation of the pseudomeningoceles, repair of dural tears, and implantation of a subarachnoid catheter for drainage. Surgery-related complications were not observed. Recurrence of pseudomeningocele was not observed for any patient at a mean follow-up of 16.5 months. This result was confirmed by magnetic resonance imaging.</p> <p>Conclusions</p> <p>We conclude that a combined treatment protocol involving open revision surgery for extirpation of pseudomeningoceles, repair of dural tears, and implantation of a subarachnoid catheter for drainage is safe and effective to treat giant pseudomeningoceles.</p

Amblyomma ticks found on cattle in the northwest of Argentina

The phytogeographical and seasonal distributions of three species of Amblyomma ticks found on cattle are presented. The material studied was collected during a four-year survey in the Northwest of Argentina. Amblyomma neumanni shows predilection for the Chaqueno Serrano district although it was also found in ecotones (phytogeographical transition zones) of the adjacent Western Chaqueno district and the province of Las Yungas. Amblyomma cajennense was found in the Western Chaqueno and Chaqueno Serrano districts as well as in the province of Las Yungas. Amblyomma parvum was found in all the Western Chaqueno district and in the northern driest part of the Chaqueno Serrano district. Amblyomma neumanni seems to be inactive in summer while A. parvum adults predominate in summer and disappear in winter. The scarcity of the preimaginal stages of A. parvum on cattle suggests that these stages prefer non-bovine hosts