Bacterial resistance to ciprofloxacin in Greece: results from the National Electronic Surveillance System. Greek Network for the Surveillance of Antimicrobial Resistance.

According to 1997 susceptibility data from the National Electronic System for the Surveillance of Antimicrobial Resistance, Greece has high rates of ciprofloxacin resistance. For most species, the frequency of ciprofloxacin-resistant isolates (from highest to lowest, by patient setting) was as follows: intensive care unit > surgical > medical > outpatient. Most ciprofloxacin-resistant strains were multidrug resistant

Study of calcium and silicon migration in refractory magnesia

Studied the effect calcium and silicon impurities have on magnesia refractories, a material frequently used to line high-temperature furnaces. Advanced analytical techniques identified and mapped these impurities in both raw materials and finished magnesia refractories. This research considerably enhanced understanding of factors influencing refractory properties and quality

Prediction of Phenotypic Antimicrobial Resistance Profiles From Whole Genome Sequences of Non-typhoidal Salmonella enterica

Surveillance of antimicrobial resistance (AMR) in non-typhoidal Salmonella enterica (NTS), is essential for monitoring transmission of resistance from the food chain to humans, and for establishing effective treatment protocols. We evaluated the prediction of phenotypic resistance in NTS from genotypic profiles derived from whole genome sequencing (WGS). Genes and chromosomal mutations responsible for phenotypic resistance were sought in WGS data from 3,491 NTS isolates received by Public Health England’s Gastrointestinal Bacteria Reference Unit between April 2014 and March 2015. Inferred genotypic AMR profiles were compared with phenotypic susceptibilities determined for fifteen antimicrobials using EUCAST guidelines. Discrepancies between phenotypic and genotypic profiles for one or more antimicrobials were detected for 76 isolates (2.18%) although only 88/52,365 (0.17%) isolate/antimicrobial combinations were discordant. Of the discrepant results, the largest number were associated with streptomycin (67.05%, n = 59). Pan-susceptibility was observed in 2,190 isolates (62.73%). Overall, resistance to tetracyclines was most common (26.27% of isolates, n = 917) followed by sulphonamides (23.72%, n = 828) and ampicillin (21.43%, n = 748). Multidrug resistance (MDR), i.e., resistance to three or more antimicrobial classes, was detected in 848 isolates (24.29%) with resistance to ampicillin, streptomycin, sulphonamides and tetracyclines being the most common MDR profile (n = 231; 27.24%). For isolates with this profile, all but one were S. Typhimurium and 94.81% (n = 219) had the resistance determinants blaTEM-1, strA-strB, sul2 and tet(A). Extended-spectrum β-lactamase genes were identified in 41 isolates (1.17%) and multiple mutations in chromosomal genes associated with ciprofloxacin resistance in 82 isolates (2.35%). This study showed that WGS is suitable as a rapid means of determining AMR patterns of NTS for public health surveillance

Molecular typing of multidrug-resistant Salmonella Blockley outbreak isolates from Greece.

During 1998, a marked increase (35 cases) in human gastroenteritis due to Salmonella Blockley, a serotype rarely isolated from humans in the Western Hemisphere, was noted in Greece. The two dominant multidrug-resistance phenotypes (23 of the 29 isolates studied) were associated with two distinct DNA fingerprints, obtained by pulsed-field gel electrophoresis of genomic DNA

Flexural behaviour of reinforced concrete jacketed columns under reversed cyclic loading

The objective of the present study is the development of an analytical model for predicting the response under reversed cyclic loading of structural members with ‘old-type’ detailing, strengthened with reinforced concrete (RC) jacketing. The analytical model introduces one additional degree of freedom between the existing member (core of the retrofitted member) and its outer RC shell, thus allowing slip to take place at the interface between the existing member and the jacket. Shear resistance mechanisms, such as aggregate interlock, friction, and dowel action, are mobilized to resist slip. Existing constitutive models are further improved to describe the mechanisms that resist sliding under cyclic shear reversals and implemented for the first time in an analytical model for deriving the response of RC jacketed members. A calculation algorithm is developed to estimate the flexural response under cyclic loading taking into account slip at the interfaces. The sensitivity of the proposed analytical model to the shear transfer mechanisms degradation rules, as well as to the crack spacing estimation, was evaluated. The validity of the proposed analytical model is assessed against experimental results

Cyclic Behavior of HPFRCC Coupling Beams with Bundled Diagonal Bars

Coupled shear walls are efficient in resisting lateral forces induced by winds and earthquakes. However, it is difficult to construct coupled shear walls particularly because current design codes require complex reinforcing details within coupling beams. The objective of this study was to develop simple reinforcement details for diagonally reinforced coupling beams; reducing transverse steel by use of high-performance fiber-reinforced cementitious composites (HPFRCCs) and bundling diagonal bars are explored. Four coupling beam specimens with length-to-depth aspect ratios of 2.0 or 3.5 were fabricated and tested under cyclic lateral displacements. The test results revealed that HPFRCC coupling beams with bundled diagonal bars and widely spaced transverse reinforcement (one-half the amount of reinforcement required by current seismic codes) exhibited excellent seismic performance compared with ordinary concrete coupling beams having code-required distributed diagonal reinforcement and transverse reinforcement