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<element name="ShareBasedCompensationByShareBasedPaymentArrangementEquityInstrumentsOtherThanOptionsOutstanding" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="instant" nillable="true" id="dawn_ShareBasedCompensationByShareBasedPaymentArrangementEquityInstrumentsOtherThanOptionsOutstanding" substitutionGroup="xbrli:item" />
<element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsOutstandingWeightedAverageGrantDateFairValue" type="num:perShareItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="dawn_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsOutstandingWeightedAverageGrantDateFairValue" substitutionGroup="xbrli:item" />
<element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsConvertedToUnvestedCommonStockWeightedAverageGrantDateFairValue" type="num:perShareItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="dawn_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsConvertedToUnvestedCommonStockWeightedAverageGrantDateFairValue" substitutionGroup="xbrli:item" />
<element name="ShareBasedCompensationByShareBasedPaymentArrangementEquityInstrumentsOtherThanOptionsConvertedToUnvestedCommonStock" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="dawn_ShareBasedCompensationByShareBasedPaymentArrangementEquityInstrumentsOtherThanOptionsConvertedToUnvestedCommonStock" substitutionGroup="xbrli:item" />
<element name="ShareBasedCompensationByShareBasedPaymentAwardConversionOfIncentiveSharesIntoRestrictedStock" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="dawn_ShareBasedCompensationByShareBasedPaymentAwardConversionOfIncentiveSharesIntoRestrictedStock" substitutionGroup="xbrli:item" />
<element name="ShareBasedCompensationByShareBasedPaymentAwardConversionOfIncentiveShareIntoRestrictedStockWeightedAverageGrantDateFairValue" type="num:perShareItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="dawn_ShareBasedCompensationByShareBasedPaymentAwardConversionOfIncentiveShareIntoRestrictedStockWeightedAverageGrantDateFairValue" substitutionGroup="xbrli:item" />
<element name="UnvestedCommonSharesMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="dawn_UnvestedCommonSharesMember" substitutionGroup="xbrli:item" />
<element name="DotOneMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="dawn_DotOneMember" substitutionGroup="xbrli:item" />
<element name="TakedaMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="dawn_TakedaMember" substitutionGroup="xbrli:item" />
<element name="TemporaryEquitySharesConvertedIntoPermanentEquity" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="dawn_TemporaryEquitySharesConvertedIntoPermanentEquity" substitutionGroup="xbrli:item" />
<element name="AdjustmentToAdditionalPaidInCapitalLossOnConversionOfTemporaryEquityIntoPermanentEquity" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="dawn_AdjustmentToAdditionalPaidInCapitalLossOnConversionOfTemporaryEquityIntoPermanentEquity" substitutionGroup="xbrli:item" xbrli:balance="debit" />
</schema>
