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  <xs:element id="exdx_FinanceLeaseCostAbstract" abstract="true" name="FinanceLeaseCostAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="exdx_CashFlowInformationOperatingAndFinanceLeasePaymentsAbstract" abstract="true" name="CashFlowInformationOperatingAndFinanceLeasePaymentsAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="exdx_WeightedAverageRemainingLeaseTermAbstract" abstract="true" name="WeightedAverageRemainingLeaseTermAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="exdx_WeightedAverageDiscountRateAbstract" abstract="true" name="WeightedAverageDiscountRateAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="exdx_USDepartmentOfJusticeCaseMember" abstract="true" name="USDepartmentOfJusticeCaseMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="exdx_LeaseTypeAxis" abstract="true" name="LeaseTypeAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="exdx_LeaseTypeDomain" abstract="true" name="LeaseTypeDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="exdx_EmbeddedFinanceLeaseMember" abstract="true" name="EmbeddedFinanceLeaseMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="exdx_RoyaltyObligationPercentageOfSales" abstract="false" name="RoyaltyObligationPercentageOfSales" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="exdx_PurchaseObligationAmendedSupplyAgreementNumberOfSuppliers" abstract="false" name="PurchaseObligationAmendedSupplyAgreementNumberOfSuppliers" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="exdx_PurchaseObligationPaidInCurrentFiscalYear" abstract="false" name="PurchaseObligationPaidInCurrentFiscalYear" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="exdx_FinanceLeaseFairValueOfLeasedAsset" abstract="false" name="FinanceLeaseFairValueOfLeasedAsset" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="exdx_WarrantLiabilityFairValueDisclosure" abstract="false" name="WarrantLiabilityFairValueDisclosure" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="exdx_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityReclassificationAdjustmentsToReclassificationOfWarrantLiabilityUponExerciseOfWarrantShares" abstract="false" name="FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityReclassificationAdjustmentsToReclassificationOfWarrantLiabilityUponExerciseOfWarrantShares" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="exdx_ShelfRegistrationStatementMember" abstract="true" name="ShelfRegistrationStatementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="exdx_SaleOfStockAuthorizedAmount" abstract="false" name="SaleOfStockAuthorizedAmount" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="exdx_SaleOfStockRemainingAuthorizedAmount" abstract="false" name="SaleOfStockRemainingAuthorizedAmount" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="exdx_ClassOfWarrantOrRightIssued" abstract="false" name="ClassOfWarrantOrRightIssued" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="exdx_ExpirationJan192026Member" abstract="true" name="ExpirationJan192026Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="exdx_ExpirationMar312026Member" abstract="true" name="ExpirationMar312026Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="exdx_ExpirationApr12026Member" abstract="true" name="ExpirationApr12026Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="exdx_NoExpirationMember" abstract="true" name="NoExpirationMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="exdx_IncentiveAwardPlan2019Member" abstract="true" name="IncentiveAwardPlan2019Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="exdx_ShareBasedCompensationArrangementByShareBasedPaymentAwardAdditionalSharesAuthorizedPercentage" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardAdditionalSharesAuthorizedPercentage" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="exdx_ShareBasedCompensationArrangementByShareBasedPaymentAwardIncreaseDecreaseInNumberOfSharesAuthorized" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardIncreaseDecreaseInNumberOfSharesAuthorized" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="exdx_CommonSharesAvailableForGrantUnderThe2019PlanMember" abstract="true" name="CommonSharesAvailableForGrantUnderThe2019PlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="exdx_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseWarrantLiabilityAmount" abstract="false" name="EffectiveIncomeTaxRateReconciliationNondeductibleExpenseWarrantLiabilityAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="exdx_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseWarrantLiabilityPercent" abstract="false" name="EffectiveIncomeTaxRateReconciliationNondeductibleExpenseWarrantLiabilityPercent" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="exdx_DeferredTaxAssetsLeaseLiability" abstract="false" name="DeferredTaxAssetsLeaseLiability" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="exdx_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsCapitalizationOfResearchAndExperimentationCosts" abstract="false" name="DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsCapitalizationOfResearchAndExperimentationCosts" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="exdx_DeferredTaxLiabilitiesRightOfUseAssets" abstract="false" name="DeferredTaxLiabilitiesRightOfUseAssets" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="exdx_DeferredTaxLiabilitiesFixedAssetsAndIntangibleAssets" abstract="false" name="DeferredTaxLiabilitiesFixedAssetsAndIntangibleAssets" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="exdx_ChangesInTheValuationAllowanceForDeferredTaxAssetsRollForward" abstract="true" name="ChangesInTheValuationAllowanceForDeferredTaxAssetsRollForward" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="exdx_TaxYearsThroughDecember312017Member" abstract="true" name="TaxYearsThroughDecember312017Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="exdx_ReportableSegmentMember" abstract="true" name="ReportableSegmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="exdx_OutsideServicesExpense" abstract="false" name="OutsideServicesExpense" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="exdx_ExchangingStockholdersMember" abstract="true" name="ExchangingStockholdersMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="exdx_ExchangeAgreementNumberOfSharesExchangedForWarrants" abstract="false" name="ExchangeAgreementNumberOfSharesExchangedForWarrants" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
</xs:schema>
