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International audience; The objective of the presented work is the bio-decontamination of small diameter long tubes by direct exposure of the tube inner surface to the plasma of a pulsed corona discharge in dry or humid argon. Bactericidal tests were conducted with Escherichia coli strain DH-1 for various exposure times. Up to similar to 5.5 log(10) reduction was observed for E. coli exposed 44 cm away from the HV electrode, for a 20 minute treatment. The factors contributing to the observed bactericidal effect include desiccation, reactive oxygen species (OH), H2O2 accumulation in the liquid phase, and UV B (and possibly VUV) in dry argon.

In this study, direct numerical simulation (DNS) and large eddy simulation (LES) of turbulent channel flow beneath a flat surface with imposed wind shear stress are presented. An open channel with friction Reynolds number Reτ= 360 has been considered, while wind shear stresses were imposed as being aligned with the flow direction or not aligned with components in streamwise and spanwise directions. The results indicate that there are differences between wind-driven flow and the case with no wind shear stress. Streaks are present close to the surface in wind-driven flow and profiles of the mean velocity, TKE and mean shear production rate in wind-driven flow are different from those in the unsheared surface flow. Large eddy simulation of wind-driven flow was also carried out to evaluate the performance of sub-grid scale models. It is shown that the features of the flow observed in DNS are well simulated by LES with a relatively small difference near the surface due to shear stress boundary condition.

Modelling of swirling flames is a difficult challenge due to their complex recirculation and vortex characteristics. Most of the traditional modelling approaches which work well in other situations fails to perform well in swirling flows when the swirl numbers are high. To this end the purpose of this paper is to perform and validate large eddy simulation of a simple, well defined, unconfined, non-reacting swirling jets experimentally investigated by Al-Abdeli and Masri. In this study the sub-grid scale turbulence has been modelled using a localised dynamic procedure. The predicted LES results show very good agreement with measured mean velocities and turbulence intensities. Overall the results show that the complex flow pattern developed from the interaction of a strongly swirling flow with the impinging primary jet in the primary zone has been captured by the present simulation.

Rationale: SCN8A mutations have been recently associated with early infantile epileptic encephalopathy with a broad phenotypic spectrum. We aim to further delineate the interictal and ictal video-EEG features of a peculiar clinical subgroup of patients affected by early onset SCN8A-related encephalopathy and epilepsy with a poor prognosis. Methods: We studied 9 SCN8A positive patients, age range: 8 months-16 years. They underwent clinical and neurophysiologic investigations including prolonged video-polygraphic recordings during wakefulness and sleep. Results: Epilepsy onset occurred at a mean age of 5 months with polymorphic, drug resistant seizures, cognitive deterioration and pyramidal/extra-pyramidal signs +/- loss of eye contact (6/9pt). Non-convulsive status epilepticus occurred in 5/9 and SUDEP in 2/9 patients. Interictal EEG at epilepsy onset was normal in 5/9 patients; during the follow up in all cases occurred progressive background deterioration and focal/multifocal spike-and-waves abnormalities, predominant in the temporo-occipital regions and/or generalized spike waves. Nocturnal sleep EEG (3/9 patients) was normally structured. Ictal video-EEG recordings were obtained in 4/9 patients (follow-up 10-25 months); all seizure types have been documented. Patients had both focal and generalized seizures (FS,GS), the latter consisting of GTCS, pseudo-absences, spasms and myoclonus. FS were usually prolonged (3-5 min), with prominent hypomotor and vegetative semiology, evolving to asymmetric tonic/tonic-clonic manifestations +/- secondary generalization. Ictal EEG showed diffuse EEG desynchronization (GS) or post-temporal seizure onset (FS), slow spreading and migration of the ictal discharge (2/4 patients) from one hemisphere to the contralateral during the same seizure. Conclusions: Despite the description of a heterogeneous epileptic phenotype associated to SCN8A encephalopathy, our patients exhibit a distinctive ictal and interictal EEG pattern, suggesting an epileptogenic dysfunction in the temporo-occipital regions, also confirmed from the recurrence of cortical visual impairment. We also speculate that the presence of ictal vegetative symptoms and the long seizures duration with frequent secondary generalization could represent risk factors for SUDEP. Awareness of this distinctive phenotype will likely enhance recognition of the disorder.