Annual, semiannual and seasonal variations of the Vertical Total Electron Content (VTEC) have been investigated during high solar activity in 2000. In this work we use Global IGS VTEC maps and Principal Component Analysis to study spatial and temporal ionospheric variability. The behavior of VTEC variations at two-hour periods, at noon and at night is analyzed. Particular characteristics associ...

Fifteen Japanese colitis patients, aged above 16 years old, infected with verotoxin-producing Escherichia coli O157 (VTEC O157) were divided into 2 treatment groups. Of the 15 patients, 6 (mean ± SD, 41.3 ± 19.0 years old) were treated with levofloxacin (LVFX), while the remaining 9 patients (32.0 ± 10.0 years old) were not treated with any antimicrobial agents. All patients complained of ab...

The adherence property of 70 verotoxigenicE. coli (VTEC) strains, not belonging to O157: H7 serotype (non-O157) was checked on HeLa cells adherence assay. These strains were isolated from patients with diarrhea and healthy individuals. The results obtained in this study revealed that localised adherence (LA) was manifested by 3 strains of which two belonged to serogroups O111, O127 and the thir...

The adsorption property of activated charcoal on verotoxin (VT)-producing Escherichia coli (VTEC) was examined using E. coli O157:H7. In the present study, E. coli O157:H7 strains were effectively adsorbed by activated charcoal. Adsorption was dose-dependent, and the maximum adsorption occurred within 5 min. At 10 mg of activated charcoal, bacteria tested were completely adsorbed. Activated cha...

Verocytotoxins VT1 and VT2,produced by Verocytotoxigenic Escherichia coli (VTEC), are encoded on temperate bacteriophages. Several studies reported the loss of the vtx genes after multiple subcultivation steps or long preservation. The objective of this study was to determine if the loss of the verocytotoxin genes can already occur during the first subcultivation step. Consequently, the stabili...

The determination of the ionospheric perturbation degree is essential to describe ionosphere state for space weather monitoring. A new method estimating spatial and temporal components Vertical Total Electron Content (VTEC) gradient introduced. based on VTEC estimated at each grid point Global Ionosphere Map (GIM) by UPC-IonSAT research group Universitat Politècnica de Catalunya. Depending requ...