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  <xsd:element abstract="true" id="poai_HelomicsHoldingCorpMember" name="HelomicsHoldingCorpMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_HelomicsOfficesLeaseAreaForLaboratoryMember" name="HelomicsOfficesLeaseAreaForLaboratoryMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_HelomicsOfficesLeaseAreaForOfficeSpaceMember" name="HelomicsOfficesLeaseAreaForOfficeSpaceMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_HelomicsOfficesMember" name="HelomicsOfficesMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_HelomicsSegmentMember" name="HelomicsSegmentMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_ImpairmentOfIntangibleAssetsSoftwareAcquired" name="ImpairmentOfIntangibleAssetsSoftwareAcquired" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element id="poai_IncreaseInOperatingLeaseRightOfAssetAndLeaseLiabilityDueToLeaseModification" name="IncreaseInOperatingLeaseRightOfAssetAndLeaseLiabilityDueToLeaseModification" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element id="poai_IndefinitelivedIntangibleAssetsExcludingGoodwillNet" name="IndefinitelivedIntangibleAssetsExcludingGoodwillNet" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant"/>
  <xsd:element id="poai_InducementSharesIssuedForDebtExtension" name="InducementSharesIssuedForDebtExtension" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_InvestorWarrantsMember" name="InvestorWarrantsMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_IssuanceOrSaleOfEquityCanBeRaised" name="IssuanceOrSaleOfEquityCanBeRaised" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_January122021RegisteredDirectOfferingMember" name="January122021RegisteredDirectOfferingMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_January212021RegisteredDirectOfferingMember" name="January212021RegisteredDirectOfferingMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_January262021RegisteredDirectOfferingMember" name="January262021RegisteredDirectOfferingMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_June162021RegisteredDirectOfferingMember" name="June162021RegisteredDirectOfferingMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_June2021OfferingMember" name="June2021OfferingMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_LaboratoryEquipmentMember" name="LaboratoryEquipmentMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_ManufacturingToolingMember" name="ManufacturingToolingMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_MaximumExpensesReimbursableToPlacementAgent" name="MaximumExpensesReimbursableToPlacementAgent" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_May2022FirstOfferingMember" name="May2022FirstOfferingMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_May2022OfferingsMember" name="May2022OfferingsMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_May2022SecondOfferingMember" name="May2022SecondOfferingMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_MeasurementInputExpectedCashFlowTermMember" name="MeasurementInputExpectedCashFlowTermMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_NoteToFinancialStatementDetailsTextual" name="NoteToFinancialStatementDetailsTextual" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_NotesToFinancialStatements" name="NotesToFinancialStatements" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_NotesToFinancialStatementsAbstract" name="NotesToFinancialStatementsAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_NumberOfWarrantsIssuedToEachInvestorPerTwoSharesOfStockPurchased" name="NumberOfWarrantsIssuedToEachInvestorPerTwoSharesOfStockPurchased" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_OtherExpensePolicyPolicyTextBlock" name="OtherExpensePolicyPolicyTextBlock" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_OtherFinitelivedIntangibleAssetsMember" name="OtherFinitelivedIntangibleAssetsMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_PatentsAndTrademarksMember" name="PatentsAndTrademarksMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_PaymentsForPenalties" name="PaymentsForPenalties" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_PlacementAgentWarrantsMember" name="PlacementAgentWarrantsMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_PreferredStockNumberOfVotesPerOnethousandthOfAShare" name="PreferredStockNumberOfVotesPerOnethousandthOfAShare" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="instant"/>
  <xsd:element id="poai_PreferredStockNumberOfVotesPerShare" name="PreferredStockNumberOfVotesPerShare" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="instant"/>
  <xsd:element id="poai_ProceedsFromIssuanceOfStockPursuantToEquityLine" name="ProceedsFromIssuanceOfStockPursuantToEquityLine" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element id="poai_ProceedsFromIssuanceOrSaleOfEquityNetOfStockIssuanceCosts" name="ProceedsFromIssuanceOrSaleOfEquityNetOfStockIssuanceCosts" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_PromissoryNote2019ConversionFeatureAgentWarrantsMember" name="PromissoryNote2019ConversionFeatureAgentWarrantsMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_PromissoryNote2019ConversionFeatureMember" name="PromissoryNote2019ConversionFeatureMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_PromissoryNote2020ConversionFeatureMember" name="PromissoryNote2020ConversionFeatureMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_PromissoryNote2020ConversionFeatureTrancheOneMember" name="PromissoryNote2020ConversionFeatureTrancheOneMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_PromissoryNote2020ConversionFeatureTrancheThreeMember" name="PromissoryNote2020ConversionFeatureTrancheThreeMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_PromissoryNote2020ConversionFeatureTrancheTwoMember" name="PromissoryNote2020ConversionFeatureTrancheTwoMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_PropertyPlantAndEquipmentUsefulLifeTableTextBlock" name="PropertyPlantAndEquipmentUsefulLifeTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_RegisteredDirectOfferingsMember" name="RegisteredDirectOfferingsMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_ReportingUnitMeasurementInput" name="ReportingUnitMeasurementInput" nillable="true" substitutionGroup="xbrli:item" type="xbrli:decimalItemType" xbrli:periodType="instant"/>
  <xsd:element id="poai_RisksAndUncertaintiesPolicyPolicyTextBlock" name="RisksAndUncertaintiesPolicyPolicyTextBlock" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_SaleOfStockAgentPlacementFeePercentOfGrossProceeds" name="SaleOfStockAgentPlacementFeePercentOfGrossProceeds" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:percentItemType" xbrli:periodType="instant"/>
  <xsd:element id="poai_SaleOfStockManagementFeePercentOfGrossProceeds" name="SaleOfStockManagementFeePercentOfGrossProceeds" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:percentItemType" xbrli:periodType="instant"/>
  <xsd:element id="poai_SaleOfStockPlacementAgentWarrantsAssignedNumberOfSecuritiesCalledByWarrantsPercentOfSharesSold" name="SaleOfStockPlacementAgentWarrantsAssignedNumberOfSecuritiesCalledByWarrantsPercentOfSharesSold" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:percentItemType" xbrli:periodType="instant"/>
  <xsd:element id="poai_SaleOfStockRemainingAvailableBalance" name="SaleOfStockRemainingAvailableBalance" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant"/>
  <xsd:element id="poai_SalesOfStockTableTextBlock" name="SalesOfStockTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_ScheduleOfSharebasedCompensationSharesAuthorizedUnderStockOptionAndWarrantPlansByExercisePriceRangeTableTextBlock" name="ScheduleOfSharebasedCompensationSharesAuthorizedUnderStockOptionAndWarrantPlansByExercisePriceRangeTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_SeriesBConvertiblePreferredStockMember" name="SeriesBConvertiblePreferredStockMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsCancelledInPeriod" name="SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsCancelledInPeriod" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_SharebasedCompensationArrangementsBySharebasedPaymentAwardOptionsCancelledInPeriodWeightedAverageExercisePrice" name="SharebasedCompensationArrangementsBySharebasedPaymentAwardOptionsCancelledInPeriodWeightedAverageExercisePrice" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_SkylineMember" name="SkylineMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_SolubleBiodtechOfficesInBirminghamAlabamaMember" name="SolubleBiodtechOfficesInBirminghamAlabamaMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_SolubleMember" name="SolubleMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_StockIncentivePlan2012Member" name="StockIncentivePlan2012Member" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_StockIssuedDuringPeriodSharesAccruedInterest" name="StockIssuedDuringPeriodSharesAccruedInterest" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_StockIssuedDuringPeriodSharesInducementToEquityLine" name="StockIssuedDuringPeriodSharesInducementToEquityLine" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_StockIssuedDuringPeriodSharesIssuedForServicesAndOtherAdjustments" name="StockIssuedDuringPeriodSharesIssuedForServicesAndOtherAdjustments" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_StockIssuedDuringPeriodSharesWarrantExercises" name="StockIssuedDuringPeriodSharesWarrantExercises" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_StockIssuedDuringPeriodSharesWarrantsExercised" name="StockIssuedDuringPeriodSharesWarrantsExercised" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_StockIssuedDuringPeriodValueAccruedInterest" name="StockIssuedDuringPeriodValueAccruedInterest" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="poai_StockIssuedDuringPeriodValueExchangeAgreementAccruedInterest" name="StockIssuedDuringPeriodValueExchangeAgreementAccruedInterest" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="poai_StockIssuedDuringPeriodValueInducementToEquityLine" name="StockIssuedDuringPeriodValueInducementToEquityLine" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="poai_StockIssuedDuringPeriodValueIssuedForServicesAndOtherAdjustments" name="StockIssuedDuringPeriodValueIssuedForServicesAndOtherAdjustments" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="poai_StockIssuedDuringPeriodValueWarrantsExercised" name="StockIssuedDuringPeriodValueWarrantsExercised" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_StockOptions2013Member" name="StockOptions2013Member" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_StockOptions2014Member" name="StockOptions2014Member" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_StockOptions2015Member" name="StockOptions2015Member" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_StockOptions2016Member" name="StockOptions2016Member" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_StockOptions2017Member" name="StockOptions2017Member" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_StockOptions2018Member" name="StockOptions2018Member" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_StockOptions2019Member" name="StockOptions2019Member" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_StockOptions2020Member" name="StockOptions2020Member" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_StockOptions2021Member" name="StockOptions2021Member" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_StockOptions2022Member" name="StockOptions2022Member" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_StockOptionsFiveMember" name="StockOptionsFiveMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_StockOptionsFourMember" name="StockOptionsFourMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_StockOptionsOneMember" name="StockOptionsOneMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_StockOptionsThreeMember" name="StockOptionsThreeMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_StockOptionsTwoMember" name="StockOptionsTwoMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_TotalIssuancesMember" name="TotalIssuancesMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_TradeNames1Member" name="TradeNames1Member" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_TumorgenesisOfficesInSalemMassachusettsMember" name="TumorgenesisOfficesInSalemMassachusettsMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_ValuationAllowancePercentage" name="ValuationAllowancePercentage" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:percentItemType" xbrli:periodType="instant"/>
  <xsd:element id="poai_ValuationAndAccountingForStockOptionsAndWarrantsPolicyPolicyTextBlock" name="ValuationAndAccountingForStockOptionsAndWarrantsPolicyPolicyTextBlock" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_WarrantFiveMember" name="WarrantFiveMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_WarrantFourMember" name="WarrantFourMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_WarrantOneMember" name="WarrantOneMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_WarrantThreeMember" name="WarrantThreeMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_WarrantTwoMember" name="WarrantTwoMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_Warrants2018Member" name="Warrants2018Member" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_Warrants2019Member" name="Warrants2019Member" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_Warrants2020Member" name="Warrants2020Member" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_Warrants2021Member" name="Warrants2021Member" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_Warrants2022Member" name="Warrants2022Member" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_WarrantsAndAgentWarrantsInConnectionWithJune2020WarrantMember" name="WarrantsAndAgentWarrantsInConnectionWithJune2020WarrantMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_WarrantsAndAgentWarrantsInConnectionWithMay2020WarrantMember" name="WarrantsAndAgentWarrantsInConnectionWithMay2020WarrantMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_WarrantsIssuedWithFirstMay2022OfferingMember" name="WarrantsIssuedWithFirstMay2022OfferingMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_ZPREDICTAMember" name="ZPREDICTAMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_ZPREDICTAOfficesInSanJoseCaliforniaMember" name="ZPREDICTAOfficesInSanJoseCaliforniaMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-1-summary-of-significant-accounting-policies-schedule-of-property-plant-and-equipment-useful-life-details" name="statement-statement-note-1-summary-of-significant-accounting-policies-schedule-of-property-plant-and-equipment-useful-life-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-1-summary-of-significant-accounting-policies-tables" name="statement-statement-note-1-summary-of-significant-accounting-policies-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-1-summary-of-significant-accounting-policies-valuation-assumptions-details" name="statement-statement-note-1-summary-of-significant-accounting-policies-valuation-assumptions-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-10-property-plant-and-equipment-schedule-of-property-plant-and-equipment-details" name="statement-statement-note-10-property-plant-and-equipment-schedule-of-property-plant-and-equipment-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-10-property-plant-and-equipment-tables" name="statement-statement-note-10-property-plant-and-equipment-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-11-segments-segments-details" name="statement-statement-note-11-segments-segments-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-11-segments-tables" name="statement-statement-note-11-segments-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-2-zpredicta-acquisition-fair-value-of-assets-acquired-and-liabilities-assumed-details" name="statement-statement-note-2-zpredicta-acquisition-fair-value-of-assets-acquired-and-liabilities-assumed-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-2-zpredicta-acquisition-pro-form-information-details" name="statement-statement-note-2-zpredicta-acquisition-pro-form-information-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-2-zpredicta-acquisition-tables" name="statement-statement-note-2-zpredicta-acquisition-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-3-inventories-schedule-of-inventory-details" name="statement-statement-note-3-inventories-schedule-of-inventory-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-3-inventories-tables" name="statement-statement-note-3-inventories-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-4-stockholders-equity-stock-options-and-warrants-schedule-of-listing-of-stock-options-and-warrants-details" name="statement-statement-note-4-stockholders-equity-stock-options-and-warrants-schedule-of-listing-of-stock-options-and-warrants-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-4-stockholders-equity-stock-options-and-warrants-stock-offerings-details" name="statement-statement-note-4-stockholders-equity-stock-options-and-warrants-stock-offerings-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-4-stockholders-equity-stock-options-and-warrants-summary-of-status-of-options-and-warrants-outstanding-details" name="statement-statement-note-4-stockholders-equity-stock-options-and-warrants-summary-of-status-of-options-and-warrants-outstanding-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-4-stockholders-equity-stock-options-and-warrants-summary-of-transactions-for-stock-options-and-warrants-details" name="statement-statement-note-4-stockholders-equity-stock-options-and-warrants-summary-of-transactions-for-stock-options-and-warrants-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-4-stockholders-equity-stock-options-and-warrants-tables" name="statement-statement-note-4-stockholders-equity-stock-options-and-warrants-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-5-derivatives-change-in-fair-value-of-derivative-liabilities-details" name="statement-statement-note-5-derivatives-change-in-fair-value-of-derivative-liabilities-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-5-derivatives-tables" name="statement-statement-note-5-derivatives-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-6-loss-per-share-antidilutive-securities-excluded-from-the-diluted-calculations-details" name="statement-statement-note-6-loss-per-share-antidilutive-securities-excluded-from-the-diluted-calculations-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-6-loss-per-share-shares-used-in-basic-and-diluted-loss-per-common-share-computations-details" name="statement-statement-note-6-loss-per-share-shares-used-in-basic-and-diluted-loss-per-common-share-computations-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-6-loss-per-share-tables" name="statement-statement-note-6-loss-per-share-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-7-income-taxes-components-of-deferred-income-taxes-details" name="statement-statement-note-7-income-taxes-components-of-deferred-income-taxes-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-7-income-taxes-reconciliation-of-income-tax-benefit-expense-details" name="statement-statement-note-7-income-taxes-reconciliation-of-income-tax-benefit-expense-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-7-income-taxes-tables" name="statement-statement-note-7-income-taxes-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-8-goodwill-and-intangibles-components-of-intangible-assets-details" name="statement-statement-note-8-goodwill-and-intangibles-components-of-intangible-assets-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-8-goodwill-and-intangibles-estimated-future-amortization-expense-details" name="statement-statement-note-8-goodwill-and-intangibles-estimated-future-amortization-expense-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-8-goodwill-and-intangibles-goodwill-details" name="statement-statement-note-8-goodwill-and-intangibles-goodwill-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-8-goodwill-and-intangibles-tables" name="statement-statement-note-8-goodwill-and-intangibles-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-9-leases-lease-information-details" name="statement-statement-note-9-leases-lease-information-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-9-leases-rent-obligation-details" name="statement-statement-note-9-leases-rent-obligation-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-9-leases-tables" name="statement-statement-note-9-leases-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-significant-accounting-policies-policies" name="statement-statement-significant-accounting-policies-policies" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
</xsd:schema>
