

<!-- RR Donnelley Xcelerate Taxonomy Schema, based on XBRL 2.1  http://www.rrdonnelley.com/ -->
<!-- Version: 6.22.4 -->
<!-- Round: 7 -->
<!-- Creation date: 2016-05-09T19:01:35Z -->
<!-- Copyright (c) 2005-2013 R.R. Donnelley & Sons Company All Rights Reserved. -->
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        <link:definition>112 - Disclosure - Net Loss Per Share</link:definition>
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        <link:definition>114 - Disclosure - Stockholders Equity</link:definition>
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        <link:definition>125 - Disclosure - Stock-Based Compensation - Additional Information (Detail)</link:definition>
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        <link:definition>126 - Disclosure - Net Loss Per Share - Computation of Basic and Diluted Earnings Per Share Attributable to Common Stockholders (Detail)</link:definition>
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