Investigation of BST thin films deposited by RF magnetron sputtering in pure Argon

International audienceBa0.5Sr0.5TiO3 (BST) thin films were deposited by rf magnetron sputtering using a Ba0.5Sr0.5TiO3 target in pure Argon on two electrodes (Pt and RuO2) at room temperature. The interface formation between BST and bottom electrode (Pt or RuO2) was investigated by XPS for thicknesses in the 1 to 50 nm range. The chemical composition of the BST layers can be modified by the electrode nature over the first five nanometers. A 1 h ex-situ annealing, under flowing oxygen at 600 degrees C, was necessary to obtain crystallized 150 nm thick BST films, as evidenced by XRD and TEM analysis

Sharing of Bacterial Strains Between Breast Milk and Infant Feces

In previous years, it has been shown that human milk is a potential source of bacteria for the infant gut. The results of this work confirm the presence of the same specific bacterial strains of Bifidobacterium, Lactobacillus, and Staphylococcus in breast milk and infant fecal samples. The identity of bacteria isolated from breast milk and infant feces from 20 mother-infant pairs was investigated at the strain level. DNA from Staphylococcus, Lactobacillus, and Bifidobacterium was detected by qRTi-PCR in nearly all samples analyzed. These samples were cultured on different agar media. One colony representative of each morphology was selected and identified at the species level combining classical tests and molecular techniques (PCR, RAPD, PFGE, and/or MLST genotyping). Breast milk and infant feces from 19 mother-infant pairs shared different Staphylococcus, Lactobacillus, and/or Bifidobacterium species and strains. Significantly, 2 mother-infant pairs shared 4 bacterial strains although most pairs shared 2. These results confirm that breast milk and infant feces from mother-infant pairs share the same strain(s), indicating that breastfeeding could contribute to the bacterial transfer from the mother to the infant and, therefore, to the infant gut colonization. © 2012 International Lactation Consultant Association.This work was supported by projects CSD2007-00063 and AGL2010-15420 (Ministerio de Ciencia e Innovación, Spain), and project S2009/AGR-1469 (Comunidad de Madrid, Spain). EJ was supported by a grant of the Ministerio de Educación y Ciencia and European Social Fund (ESF) (PTA2008-1019-P).Peer Reviewe

beta-lactam antibiotic resistance in aerobic commensal fecal flora of newborns

Background: The purpose of the present paper was to prospectively determine the rate of beta-lactam antibiotic resistance in commensal fecal flora of newborns and the risk factors leading to this colonization