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  <xs:element id="qti_ThirdOmnibusAmendmentMember" abstract="true" name="ThirdOmnibusAmendmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="qti_DebtInstrumentConvertibleTriggeredPrincipalAmount" abstract="false" name="DebtInstrumentConvertibleTriggeredPrincipalAmount" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="qti_DebtInstrumentConvertibleAdditionalReductionAmount" abstract="false" name="DebtInstrumentConvertibleAdditionalReductionAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="qti_DebtInstrumentExtensionFeePayable" abstract="false" name="DebtInstrumentExtensionFeePayable" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="qti_DebtInstrumentProposedPrepaymentBusinessDays" abstract="false" name="DebtInstrumentProposedPrepaymentBusinessDays" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="qti_PrepaymentPremiumPercentage" abstract="false" name="PrepaymentPremiumPercentage" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="qti_CashProceedsFromAnyExtraordinaryReceiptAmount" abstract="false" name="CashProceedsFromAnyExtraordinaryReceiptAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="qti_DebtInstrumentConvertibleCashProceedsBusinessDays" abstract="false" name="DebtInstrumentConvertibleCashProceedsBusinessDays" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="qti_CashProceedsOfSuchExtraordinaryReceiptPercent" abstract="false" name="CashProceedsOfSuchExtraordinaryReceiptPercent" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="qti_NetCashProceedsThereofPercentage" abstract="false" name="NetCashProceedsThereofPercentage" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="qti_NetCashProceedsEqualExceedingAmount" abstract="false" name="NetCashProceedsEqualExceedingAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="qti_DebtInstrumentConvertibleSubsidiaryShallPrepayBusinessDays" abstract="false" name="DebtInstrumentConvertibleSubsidiaryShallPrepayBusinessDays" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="qti_DebtInstrumentConvertibleThresholdBusinessDays" abstract="false" name="DebtInstrumentConvertibleThresholdBusinessDays" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="qti_DebtInstrumentConvertibleAfterTheEndOfEachMonthBusinessDays" abstract="false" name="DebtInstrumentConvertibleAfterTheEndOfEachMonthBusinessDays" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="qti_AggregateAmountOfPaymentsOfAccountsReceivableActuallyReceivedPercentage" abstract="false" name="AggregateAmountOfPaymentsOfAccountsReceivableActuallyReceivedPercentage" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="qti_DebtInstrumentMultiplierPercentage" abstract="false" name="DebtInstrumentMultiplierPercentage" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="qti_NetCashProceedsPercentage" abstract="false" name="NetCashProceedsPercentage" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="qti_OperatingLeaseRightOfUseAssetsAbstract" abstract="true" name="OperatingLeaseRightOfUseAssetsAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="qti_LessThan12MonthsMember" abstract="true" name="LessThan12MonthsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="qti_CommonStockWarrantsMember" abstract="true" name="CommonStockWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="qti_PreFundedWarrantMember" abstract="true" name="PreFundedWarrantMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="qti_ShareBasedPaymentArrangementOptionsOutstandingMember" abstract="true" name="ShareBasedPaymentArrangementOptionsOutstandingMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="qti_ShareBasedPaymentArrangementRSUsOutstandingMember" abstract="true" name="ShareBasedPaymentArrangementRSUsOutstandingMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="qti_ShareBasedPaymentArrangementOptionsAvailableMember" abstract="true" name="ShareBasedPaymentArrangementOptionsAvailableMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="qti_InducementEquityIncentivePlanMember" abstract="true" name="InducementEquityIncentivePlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="qti_RSUsOutstandingUnderTheInducementEquityIncentivePlanMember" abstract="true" name="RSUsOutstandingUnderTheInducementEquityIncentivePlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="qti_SubscriptionAgreementsMember" abstract="true" name="SubscriptionAgreementsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="qti_PotentialSharesFromConvertibleNotesMember" abstract="true" name="PotentialSharesFromConvertibleNotesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="qti_PubCoWarrantsExpiringMarch42029Member" abstract="true" name="PubCoWarrantsExpiringMarch42029Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="qti_SubscriptionWarrantMember" abstract="true" name="SubscriptionWarrantMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="qti_SaleOfStockVolumeWeightedTradingPricePercentage" abstract="false" name="SaleOfStockVolumeWeightedTradingPricePercentage" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="qti_SaleOfStockInitialExerciseDateToPurchaseTerm" abstract="false" name="SaleOfStockInitialExerciseDateToPurchaseTerm" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="qti_ClassOfWarrantOrRightSharesSubscribedButUnissued" abstract="false" name="ClassOfWarrantOrRightSharesSubscribedButUnissued" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="qti_ClassOfWarrantOrRightPurchasePriceOfWarrantsOrRights" abstract="false" name="ClassOfWarrantOrRightPurchasePriceOfWarrantsOrRights" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType"/>
  <xs:element id="qti_ClassOfWarrantOrRightPurchasePriceOfWarrantsOrRightsPercentage" abstract="false" name="ClassOfWarrantOrRightPurchasePriceOfWarrantsOrRightsPercentage" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="qti_ClassOfWarrantOrRightVolumeWeightedTradingPriceDays" abstract="false" name="ClassOfWarrantOrRightVolumeWeightedTradingPriceDays" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="qti_A2024EquityIncentivePlanMember" abstract="true" name="A2024EquityIncentivePlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="qti_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsCancelledInPeriod" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsCancelledInPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="qti_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsCancelledInPeriodWeightedAverageExercisePrice" abstract="false" name="ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsCancelledInPeriodWeightedAverageExercisePrice" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType"/>
  <xs:element id="qti_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExercisable" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExercisable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="qti_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExpectedToVest" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExpectedToVest" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="qti_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExpectedToVestWeightedAverageGrantDateFairValue" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExpectedToVestWeightedAverageGrantDateFairValue" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType"/>
  <xs:element id="qti_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExpectedToVestWeightedAverageRemainingContractualTerm" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExpectedToVestWeightedAverageRemainingContractualTerm" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="qti_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueGranted" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueGranted" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="qti_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueExpectedToVest" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueExpectedToVest" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="qti_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsWeightedAverageGrantDateFairValue" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsWeightedAverageGrantDateFairValue" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType"/>
  <xs:element id="qti_CustomerAMember" abstract="true" name="CustomerAMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="qti_EstimatedAnnualEffectiveIncomeTaxRateReconciliationPercent" abstract="false" name="EstimatedAnnualEffectiveIncomeTaxRateReconciliationPercent" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="qti_EarnoutMember" abstract="true" name="EarnoutMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="qti_RSUsOutstandingMember" abstract="true" name="RSUsOutstandingMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="qti_A2020NotesMember" abstract="true" name="A2020NotesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="qti_WorkingCapitalLoanAndExtensionNoteMember" abstract="true" name="WorkingCapitalLoanAndExtensionNoteMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="qti_WorkingCapitalLoansMember" abstract="true" name="WorkingCapitalLoansMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="qti_NumberOfConvertibleNotesIssued" abstract="false" name="NumberOfConvertibleNotesIssued" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="qti_NumberOfStockholders" abstract="false" name="NumberOfStockholders" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="qti_ReportableSegmentMember" abstract="true" name="ReportableSegmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
</xs:schema>
