Publications by authors named "S B Libby"

The interplay of kinetic electron physics and atomic processes in ultrashort laser-plasma interactions provides a comprehensive understanding of the impact of the electron energy distribution on plasma properties. Notably, nonequilibrium electrons play a vital role in collisional ionization, influencing ionization degrees and spectra. This paper introduces a computational model that integrates the physics of kinetic electrons and atomic processes, utilizing a Boltzmann equation for nonequilibrium electrons and a collisional-radiative model for atomic state populations.

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Article Synopsis
  • Salmonella enterica serovar Typhi (S. Typhi) causes Typhoid fever, and while blood cultures are the best way to diagnose it, they're hard to use in resource-limited areas.* -
  • Researchers developed a novel process control organism (PCO) as a biosafe surrogate to test various environmental surveillance methods for detecting S. Typhi in water.* -
  • The PCO successfully mimicked S. Typhi in lab tests and was consistently detected in wastewater samples from India and Malawi, making it a reliable tool for validating environmental detection methods for this pathogen.*
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Unlabelled: serovars Typhi and Paratyphi cause a prolonged illness known as enteric fever, whereas other serovars cause acute gastroenteritis. Mechanisms responsible for the divergent clinical manifestations of nontyphoidal and enteric fever infections have remained elusive. Here, we show that .

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Background: Shigella spp have been associated with community-wide outbreaks in urban settings. We analysed a sustained shigellosis outbreak in Seattle, WA, USA, to understand its origins and mechanisms of antimicrobial resistance, define ongoing transmission patterns, and optimise strategies for treatment and infection control.

Methods: We did a retrospective study of all Shigella isolates identified from stool samples at the clinical laboratories at Harborview Medical Center and University of Washington Medical Center (Seattle, WA, USA) from May 1, 2017, to Feb 28, 2022.

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Efforts to understand molecular mechanisms of pathogenesis of the human-restricted pathogen Salmonella enterica serovar Typhi, the causative agent of typhoid fever, have been hampered by the lack of a tractable small animal model. This obstacle has been surmounted by a humanized mouse model in which genetically modified mice are engrafted with purified CD34+ stem cells from human umbilical cord blood, designated CD34+ Hu-NSG (formerly hu-SRC-SCID) mice. We have shown that these mice develop a lethal systemic infection with S.

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