background and objectives: β-lactamase production is the predominant mechanism for resistance to β-lactams in enterobacteriaceae. the producing isolates are often multidrug resistant and are major hosts for extended spectrum β-lactamases. this study was designed to determine the prevalence of extended-spectrum β-lactamase producing isolates of escherichia coli and klebsiella pneumoniae and thei...

The Class D β-lactamases have emerged as a prominent resistance mechanism against β-lactam antibiotics that previously had efficacy against infections caused by pathogenic bacteria, especially by Acinetobacter baumannii and the Enterobacteriaceae. The phenotypic and structural characteristics of these enzymes correlate to activities that are classified either as a narrow spectrum, an extended s...

We show here that the spectrum of the family of noncommutative harmonic oscillators Qw(α,β)(x,D) for α, β ∈ R+ in the range αβ = 1, is [0,+∞) and is entirely essential spectrum. The previous existing results concern the case αβ > 1 (case in which Qw(α,β)(x,D) is globally elliptic with a discrete spectrum whose qualitative properties are being extensively studied), and ours therefore extends the...

Aeromonas species, aquatic Gram-negative bacilli, distributed globally and ubiquitously in the natural environment, may be implicated in a variety of human diseases. They can produce various β-lactamases which confer resistance to a broad spectrum of β-lactams, and therefore in vitro susceptibility testing must be used to guide antimicrobial therapy. However, conventional in vitro susceptibilit...

An exact analytic calculation is presented for the spectrum of relic gravi-tational waves in the scenario of accelerating Universe Ω Λ + Ω m = 1. The spectrum formula contains explicitly the parameters of acceleration, inflation , reheating, and the (tensor/scalar) ratio, so that it can be employed for a variety of cosmological models. We find that the spectrum depends on the behavior of the pr...

Knowledge of the energy spectrum of 8B neutrinos is important for interpreting experiments that detect energetic neutrinos from the Sun. The neutrino spectrum deviates from the allowed β-decay approximation because of the broad α-unstable 8Be final state and recoil order corrections. We have measured the total energy of the α particles emitted following the β decay of 8B. The measured α spectru...

the molecular weight distribution of 4 commercial isotactic polypropylene (ipp) samples was estimated using rheological data. the dynamic moduli data, obtained from rheological measurements in linear viscoelastic region was used for calculation of relaxation time spectrum, h(τ) and then shear relaxation modulus, g(t). finally, applying thimm kernel function and relaxation modulus data in genera...