Charles R. Williams

Learn More
Neurofibromatosis type 1 (NF1) is one of the most frequent genetic disorders, affecting 1:3,000 worldwide. Identification of genotype-phenotype correlations is challenging because of the wide range clinical variability, the progressive nature of the disorder, and extreme diversity of the mutational spectrum. We report 136 individuals with a distinct(More)
We examine how entrepreneurial entry by diversifying and de novo firms in new industries leads to different levels of performance. We propose that these types of firms differ in dynamic capabilities, which help them overcome growth impediments and transition to incumbency in the industry. Growth impediments arise at larger size, older tenure levels in(More)
This study's premise is that ingratiation and organizational citizenship behaviors are similar hut that supervisors will respond differently to employees depending on whether they lahel their extrarole behaviors as ingratiation or as organizational citizenship hehavior (OCB). Variables based on Kelley's covariation model did not greatly influence(More)
Platforms have evolved beyond just being organized as multi-sided markets with complementors selling to users. Complementors are often unpaid, working outside of a price system and driven by heterogeneous sources of motivation—which should affect how they respond to platform growth. Does reliance on network effects and strategies to attract large numbers of(More)
It is widely acknowledged that the ability to redeploy and recombine internal resources is an important source of competitive advantage. This paper deepens our understanding of the factors a¤ecting internal redeployment by exploring how shared ownership and managers' family ties in ‡uence top managerial mobility in business groups. We …nd that managerial(More)
Awareness of non-O157 Shiga toxin-producing Escherichia coli (non-O157 STEC) as a food safety concern has increased recently. In October 2009, a CΉφΉϸ͊΢͞μ P͊φΉφΉΩ΢ ϭ̮μ ͔ΉΛ͊͆ ϭΉφΆ φΆ͊ ΔΊD!͞μ Food Safety and Inspection Service (FSIS) to declare all enterohemorrhagic (EHEC) Shiga toxin-producing serotypes of Escherichia coli (STEC), including non-O157(More)
INTRODUCTION   Deep brain stimulation applied to the periaqueductal grey matter (PAG) of the midbrain in humans has been shown to increase or decrease arterial blood pressure during rest and to resist the postural fall on standing. The mechanism by which this effect is elicited is unknown. We hypothesize that PAG stimulation modulates performance of the(More)
of Dissertation ABSTRACT The purpose of this study was to determine the impact block scheduling has on (a) student academic achievement, discipline, and attendance, and (b) administrator, teacher, and student perceptions. The study compared 2005–2010 data from a high school utilizing the A/B block schedule and a high school under a traditional schedule, in(More)
Corresponding author. All authors contributed equally to the study and the names are listed in random order. We thank the Ewing Marion Kauffman Foundation for grant funding used to support this research. We appreciate comments received from seminar participants at Duke, Illinois, the 2006 SMS and the 2007 AoM meetings. The usual disclaimer applies.