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  <element name="UnauditedInterimFinancialInformationPolicyTextBlock" id="zfgn_UnauditedInterimFinancialInformationPolicyTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="UnvestedRestrictedCommonStockMember" id="zfgn_UnvestedRestrictedCommonStockMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ValuationAllowanceDeferredTaxAssetChangeInAmountDecrease" id="zfgn_ValuationAllowanceDeferredTaxAssetChangeInAmountDecrease" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ValuationAllowanceDeferredTaxAssetChangeInAmountIncrease" id="zfgn_ValuationAllowanceDeferredTaxAssetChangeInAmountIncrease" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
</schema>





