Phase Transition to Turbulence via Moving Fronts.

Directed percolation (DP), a universality class of continuous phase transitions, has recently been established as a possible route to turbulence in subcritical wall-bounded flows. In canonical straight pipe or planar flows, the transition occurs via discrete large-scale turbulent structures, known as puffs in pipe flow or bands in planar flows, which either self-replicate or laminarize. However, these processes might not be universal to all subcritical shear flows.

Extreme events in transitional turbulence.

Transitional localized turbulence in shear flows is known to either decay to an absorbing laminar state or to proliferate via splitting. The average passage times from one state to the other depend super-exponentially on the Reynolds number and lead to a crossing Reynolds number above which proliferation is more likely than decay. In this paper, we apply a rare-event algorithm, Adaptative Multilevel Splitting, to the deterministic Navier-Stokes equations to study transition paths and estimate large passage times in channel flow more efficiently than direct simulations.

[B-cell pseudolymphoma caused by aluminium hydroxide following hyposensitization therapy].

Aluminium hydroxide is used as an adjuvant in vaccines. We describe the case of a patient who presented a persistent adverse local reaction to aluminium hydroxide due to hyposensitization therapy to dust mites. Multiple painful and pruriginous subcutaneous nodules were observed in both arms, along with hypertrichosis at the injection site.

[Disorders of hemostasis in orthotopic liver transplantation in an experiment].

The study was undertaken to examine blood coagulative parameters in experimental orthotopic liver grafting. Plasma hemostatic parameters were studied in animals undergone successful and unsuccessful surgery. The preservation of a graft, anesthetization, and blood-substitute therapy were found to substantially affect the severity of hemostatic disorders.