University of Avignon

About: University of Avignon is a education organization based out in Avignon, Provence-Alpes-Côte-d'Azur, France. It is known for research contribution in the topics: Population & Speaker recognition. The organization has 1526 authors who have published 3766 publications receiving 88928 citations.

Effects of porcine bile on survival of Bacillus cereus vegetative cells and Haemolysin BL enterotoxin production in reconstituted human small intestine media.

Abstract: Aims: To determine the effects of porcine bile (PB) on Bacillus cereus vegetative cells and Haemolysin BL (HBL) enterotoxin production in reconstituted small intestine media (IM). Methods and Results: The effects of PB on the growth of B. cereus vegetative cells in reconstituted IM at PB concentrations ranging between 0 and 3·0 g l−1 were examined. Four gastric media (GM) named GM-J broth (JB), GM-chicken, GM-milk and GM-pea were prepared by mixing equal volumes of a gastric electrolyte solution containing pepsin with JB, chicken, semi-skimmed milk and pea soup, respectively. Bacillus cereus was inoculated at approx. 2 × 104 CFU ml−1 into each GM at pH 5·0 for 30 min at 37°C, then mixed to the same volume of double-strength JB (IM) and PB to give concentrations of between 0 and 3·0 g of PB per litre at pH 6·5 and incubated at 37°C. The diarrhoeal B. cereus strain F4430/73 grew in IM-JB, IM-chicken and IM-milk at PB concentrations of up to 0·6, 1·5 and 1·2 g l−1, respectively. Growth was observed in IM-pea at all concentrations tested. The highest PB concentrations allowing a 3 log B. cereus increase in IM-JB, IM-chicken, IM-milk and IM-pea after a 7–10 h incubation period were 0·3, 0·9, 0·9 and 3·0 g l−1, respectively. The effect of PB on B. cereus cells was strongest in IM-JB, followed by IM-chicken, IM-milk and IM-pea. Haemolysin BL enterotoxin was detectable in IM-chicken, IM-whole milk, IM-semi-skimmed milk and IM-pea up to PB concentrations of only 0·6, 0·6, 0·3 and 0·9 g l−1, respectively. The diarrhoeal B. cereus strain F4433/73 behaved similarly to B. cereus strain F4430/73, whereas the food strain TZ415 was markedly more susceptible to bile. Conclusions: The tolerance of B. cereus cells to PB strongly depends on the type of food contained in the IM. Bile tolerance is also subject to strain variation. Significance and Impact of the Study: The probability that B. cereus cells will grow in the small intestine, produce toxins and cause diarrhoea is likely to depend on the food they are ingested with, on the bile tolerance of the B. cereus strain, and on bile concentration.

Slotted aloha with priorities and random power

Abstract: We study distributed choice of retransmission probabilities in slotted Aloha under power differentiation. We consider random transmission powers and further study the role of priorities (through power control) given either to new arriving packets or to backlogged ones. We study both the cooperative team problem in which a common objective is jointly optimized as well as the noncooperative game problem. We show that the new proposed schemes not only improve the average performances considerably but are also able in some cases to eliminate the bi-stable nature of the slotted Aloha.

EEG-NeuroBioFeedback Treatment of Patients with Brain Injury: Part 2: Changes in EEG Parameters versus Rehabilitation

Abstract: Background. A sample of 27 patients with brain injury distributed in five clinical classes was examined for pre- and post-treatment symptoms and associated power spectra. Methods. Changes in electroencephalographic (EEG) compressed spectral arrays were analyzed with respect to the rate of rehabilitation and correlated with a checklist of symptoms for each patient and the group as a whole. Results. Targeted decreases in slower (3–7 Hz) and higher (24–32 Hz) frequencies, and EMG (70–90 Hz), and increases of alpha (8–12 Hz) and mid-range beta frequencies (15–18 Hz) were achieved following Neuro-BioFeedback (NBF) treatment using positive reward tones and a simultaneous visual reward. The impact of gender and age class influence was assessed against treatment results. Single lead EEG power spectra changes were analyzed for hemispherectomized patients, stroke, car accident and trauma patients. A common EEG pattern was observed for a group of patients exhibiting vertigo with two subgroups in which verti...