Publications by authors named "M J Hill"

Background: Convenience, privacy, and cost-effectiveness associated with web-based data collection have facilitated the recent expansion of web-based survey research. Importantly, however, practical benefits of web-based survey research, to scientists and participants alike, are being overshadowed by the dramatic rise in suspicious and fraudulent survey submissions. Misinformation associated with survey fraud compromises data quality and data integrity with important implications for scientific conclusions, clinical practice, and social benefit.

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Ultra-intense short-pulse lasers interacting with matter are capable of generating exceptionally bright secondary radiation sources. The short pulse duration (picoseconds to nanoseconds), small source size (sub-mm), and comparable high peak flux to conventional single particle sources make them an attractive source for radiography using a combination of particle species, known as multimodal imaging. Simultaneous x-ray and MeV neutron imaging of multi-material objects can yield unique advantages for material segmentation and identification within the full sample.

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Background & Purpose: Non-stenotic (< 50%) carotid plaques are increasingly recognized as a potential mechanism for ischemic stroke. We assessed the prevalence of such plaques in patients with low-risk neurologic events and evidence of DWI (Diffusion Weighted Imaging)-positive ischemia.

Methods: This is a post-hoc exploratory analysis from the DOUBT study, a prospective, observational, multicenter study of patients with low-risk transient or persistent minor focal neurological symptoms.

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Bacteria communicate through the accumulation of autoinducer (AI) molecules that regulate gene expression at critical densities in a process called quorum sensing (QS). Extensive work using simple systems and single strains of bacteria have revealed a role for QS in the regulation of virulence factors and biofilm formation; however, less is known about QS dynamics among communities, especially in vivo. In this review, we summarize the diversity of QS signals as well as their ability to influence "non-target" behaviors among species that have receptors but not synthases for those signals.

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