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  <xs:element id="exdx_AdjustmentsToAdditionalPaidInCapitalTemporaryEquityWithBeneficialConversionFeature" abstract="false" name="AdjustmentsToAdditionalPaidInCapitalTemporaryEquityWithBeneficialConversionFeature" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="exdx_LongTermDebtIncludingUndiscountedInterest" abstract="false" name="LongTermDebtIncludingUndiscountedInterest" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="exdx_ReceivableBenchmarkMember" abstract="true" name="ReceivableBenchmarkMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="exdx_CoronavirusAidReliefAndEconomicSecuritiesCARESActOtherNonOperatingIncomeExpense" abstract="false" name="CoronavirusAidReliefAndEconomicSecuritiesCARESActOtherNonOperatingIncomeExpense" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="exdx_Government1Member" abstract="true" name="Government1Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="exdx_PrepaidMaintenanceAndInsuranceContracts" abstract="false" name="PrepaidMaintenanceAndInsuranceContracts" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="exdx_ShareBasedCompensationArrangementByShareBasedPaymentAwardIncreaseDecreaseInNumberOfSharesAuthorized" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardIncreaseDecreaseInNumberOfSharesAuthorized" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="exdx_RoyaltyObligationPercentageOfSales" abstract="false" name="RoyaltyObligationPercentageOfSales" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="num:percentItemType"/>
  <xs:element id="exdx_DebtInstrumentPeriodicPrincipalNumberOfPayments" abstract="false" name="DebtInstrumentPeriodicPrincipalNumberOfPayments" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
</xs:schema>
