William A. Walker

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One hundred randomly selected mandibular incisors were examined to assess the prevalence and location of two canals and to describe the canal anatomy that may be encountered during apical surgery. Sections of the root were cut at 1, 2, and 3 mm from the apex, simulating a 20-degree beveled surgical resection. The sections were digitally imaged at x 50(More)
Necrotizing enterocolitis (NEC) is an inflammatory disease of the newborn bowel, primarily affecting premature infants. Early intestinal colonization has been implicated in the pathogenesis of NEC. The objective of this prospective case-control study was to evaluate differences in the intestinal microbiota between infants who developed NEC and unaffected(More)
The ecological significance of fish and squid of the mesopelagic zone (200 m-1000 m) is evident by their pervasiveness in the diets of a broad spectrum of upper pelagic predators including other fishes and squids, seabirds and marine mammals. As diel vertical migrators, mesopelagic micronekton are recognized as an important trophic link between the deep(More)
There are formatting errors in Table 2. The exponential equations should appear with super-script formatting. Please see the correct Table 2 and its caption here. Copyright: This is an open access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose.(More)
BACKGROUND The initial acquisition and early development of the intestinal microbiome during infancy are important to human health across the lifespan. Mode of birth, antibiotic administration, environment of care, and nutrition have all been shown to play a role in the assembly of the intestinal microbiome during early life. For preterm infants, who are(More)
This study evaluated the sectional gutta-percha obturation technique advocated by Lightspeed Technology, Inc. Single relatively straight-canaled teeth were prepared with rotary instruments and divided into three groups. Groups A and B served as controls and were obturated using laterally condensed gutta-percha and either Roth's 801 or Ketac-Endo sealer.(More)
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