Publications by authors named "M M Shneĭder"

This paper reports on the use of coherent microwave scattering (CMS) for spatially resolved electron number density measurements of elongated plasma structures induced at mid-IR femtosecond filamentation in air. The presented studies comprise one-dimensional mapping of laser filaments induced via 3.9 µm, 127.

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We describe a new optical diagnostic for determining the composition of gases by measuring the motion of atoms and molecules trapped within very deep optical lattices. This non-resonant method is analogous to conventional Raman scattering, except that the observed spectral features relate to the oscillatory center-of-mass motion of each species within the lattice, determined uniquely by their respective polarizability-to-mass ratio. Depending on the density of the probed sample, detection occurs either via optical scattering at the high end or via non-resonant ionization at the lower end.

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Article Synopsis
  • Capsular polysaccharide (CPS) from the bacterial pathogen Acinetobacter baumannii is a key factor in its virulence, specifically the KL58 variant produced by the strain MRSN 31468.
  • The CPS structure is characterized as a branched tetrasaccharide containing various sugar units, including glucose, galactose, N-acetyl-galactosamine, and a unique acid, indicating complex biosynthesis processes.
  • The study identified specific genes responsible for synthesizing components of CPS, noting that an acetyltransferase linked to a prophage may influence its structural modifications, while a related CPS variant contains a different epimer not present in MRSN 31468.
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In this paper we study defocusing and non-paraxial effects associated with nanosecond pulsed laser beam propagation through femtosecond laser generated plasmas. Simulations were performed using a non-reduced wave propagation equation to highlight the role of spatial beam shaping of the nanosecond pulse in improving the laser propagation characteristics. We show that optimizing the shape of the laser intensity profile at the focus using a beam with the ring-liked focus helps to reduce both defocusing and non-paraxial effects.

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Bacteria use the type VI secretion system (T6SS) to secrete toxins into pro- and eukaryotic cells via machinery consisting of a contractile sheath and a rigid tube. Rearrangement hotspot (Rhs) proteins represent one of the most common T6SS effectors. The Rhs C-terminal toxin domain displays great functional diversity, while the Rhs core is characterized by YD repeats.

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