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  <xsd:element abstract="true" id="poai_AssetPurchaseAgreementWithInventabiotechAndItsSubsidiariesSolubleAndBiodethMember" name="AssetPurchaseAgreementWithInventabiotechAndItsSubsidiariesSolubleAndBiodethMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_AssetPurchaseAgreementWithQuantitativeMedicineMember" name="AssetPurchaseAgreementWithQuantitativeMedicineMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_AssetPurchaseSharesIssuedSharesEscrowDepositToBeReleasedUponNineMonthsAnniversaryOfClosing" name="AssetPurchaseSharesIssuedSharesEscrowDepositToBeReleasedUponNineMonthsAnniversaryOfClosing" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="instant"/>
  <xsd:element id="poai_AssetPurchaseSharesIssuedSharesEscrowDepositToBeReleasedUponSixMonthsAnniversaryOfClosing" name="AssetPurchaseSharesIssuedSharesEscrowDepositToBeReleasedUponSixMonthsAnniversaryOfClosing" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="instant"/>
  <xsd:element abstract="true" id="poai_BorrowingsAgainstEquityLineMember" name="BorrowingsAgainstEquityLineMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_BorrowingsAgainstEquityLineOneMember" name="BorrowingsAgainstEquityLineOneMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_BorrowingsAgainstEquityLineThreeMember" name="BorrowingsAgainstEquityLineThreeMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_BorrowingsAgainstEquityLineTwoMember" name="BorrowingsAgainstEquityLineTwoMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_BridgeLoanAgreementMember" name="BridgeLoanAgreementMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_BridgeLoanWarrantsMember" name="BridgeLoanWarrantsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_BridgeNotesMember" name="BridgeNotesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_BusinessAcquisitionEquityInterestIssuedOrIssuableNumberOfSharesHeldInEscrow" name="BusinessAcquisitionEquityInterestIssuedOrIssuableNumberOfSharesHeldInEscrow" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_BusinessAcquisitionRevaluationGainLossOnAcquisition" name="BusinessAcquisitionRevaluationGainLossOnAcquisition" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="poai_BusinessAcquisitionRightToReclaimNumberOfShares" name="BusinessAcquisitionRightToReclaimNumberOfShares" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="instant"/>
  <xsd:element id="poai_BusinessCombinationNotesAndInterestDueForgave" name="BusinessCombinationNotesAndInterestDueForgave" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="poai_BusinessCombinationRecognizedIdentifiableAssetAcquiredAndLiabilityAssumedCurrentLiabilitiesLeaseObligation" name="BusinessCombinationRecognizedIdentifiableAssetAcquiredAndLiabilityAssumedCurrentLiabilitiesLeaseObligation" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant"/>
  <xsd:element id="poai_BusinessCombinationRecognizedIdentifiableAssetAcquiredAndLiabilityAssumedNoncurrentLiabilitiesLeaseObligation" name="BusinessCombinationRecognizedIdentifiableAssetAcquiredAndLiabilityAssumedNoncurrentLiabilitiesLeaseObligation" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant"/>
  <xsd:element id="poai_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccruedExpenses" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccruedExpenses" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant"/>
  <xsd:element id="poai_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedRightOfUseAssets" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedRightOfUseAssets" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant"/>
  <xsd:element abstract="true" id="poai_CarnegieMellonUniversityMember" name="CarnegieMellonUniversityMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRightsPercentOfStockPrice" name="ClassOfWarrantOrRightExercisePriceOfWarrantsOrRightsPercentOfStockPrice" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant"/>
  <xsd:element id="poai_ClassOfWarrantOrRightExercisedDuringPeriodExercisePrice" name="ClassOfWarrantOrRightExercisedDuringPeriodExercisePrice" nillable="true" substitutionGroup="xbrli:item" type="num:perShareItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_ClassOfWarrantOrRightIssuedDuringPeriod" name="ClassOfWarrantOrRightIssuedDuringPeriod" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_ClassOfWarrantOrRightNumberOfWarrantsVestedAndExercisable" name="ClassOfWarrantOrRightNumberOfWarrantsVestedAndExercisable" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="instant"/>
  <xsd:element id="poai_ClassOfWarrantOrRightOutstandingWeightedAverageRemainingContractualTerm" name="ClassOfWarrantOrRightOutstandingWeightedAverageRemainingContractualTerm" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_ClassOfWarrantOrRightPercentageOfSharesIssuedPursuantToExerciseOfExistingWarrant" name="ClassOfWarrantOrRightPercentageOfSharesIssuedPursuantToExerciseOfExistingWarrant" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant"/>
  <xsd:element id="poai_ClassOfWarrantOrRightPurchasePricePerWarrant" name="ClassOfWarrantOrRightPurchasePricePerWarrant" nillable="true" substitutionGroup="xbrli:item" type="num:perShareItemType" xbrli:periodType="instant"/>
  <xsd:element id="poai_ConsiderationForExtinguishmentOfDebt" name="ConsiderationForExtinguishmentOfDebt" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_ConversionFromSeriesDPreferredStockToCommonStockMember" name="ConversionFromSeriesDPreferredStockToCommonStockMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_ConversionFromSeriesEPreferredStockToCommonStockMember" name="ConversionFromSeriesEPreferredStockToCommonStockMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_ConversionOfBridgeLoanToCommonStockMember" name="ConversionOfBridgeLoanToCommonStockMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_ConversionOfPromissoryNoteIntoCommonStockMember" name="ConversionOfPromissoryNoteIntoCommonStockMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_ConversionOfSeriesDPreferredStockToCommonStockMember" name="ConversionOfSeriesDPreferredStockToCommonStockMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_ConversionOfStockSharesIssuedPercentageOfOutstandingShares" name="ConversionOfStockSharesIssuedPercentageOfOutstandingShares" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_ConvertibleDebt2020Warrants2Member" name="ConvertibleDebt2020Warrants2Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_ConvertibleDebt2020WarrantsMember" name="ConvertibleDebt2020WarrantsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_ConvertiblePreferredStockConversionRate" name="ConvertiblePreferredStockConversionRate" nillable="true" substitutionGroup="xbrli:item" type="xbrli:pureItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_ConvertiblePromissoryNoteMember" name="ConvertiblePromissoryNoteMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_CorporateOfficeMinnesotaMember" name="CorporateOfficeMinnesotaMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_CorporateOfficeMinnesotaUsedForManufacturingMember" name="CorporateOfficeMinnesotaUsedForManufacturingMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_CorporateOfficeMinnesotaUsedForOfficeSpaceMember" name="CorporateOfficeMinnesotaUsedForOfficeSpaceMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_CytoBioscienceMember" name="CytoBioscienceMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_DawsonJamesSecuritiesIncAndPaulsonInvestmentCompanyLlcMember" name="DawsonJamesSecuritiesIncAndPaulsonInvestmentCompanyLlcMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_DebtExtinguishmentCosts" name="DebtExtinguishmentCosts" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_DebtIssuedInSeptember2018September2019AndFebruary2020Member" name="DebtIssuedInSeptember2018September2019AndFebruary2020Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_DebtModificationCosts" name="DebtModificationCosts" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="poai_DeferredTaxAssetsLiabilitiesGross" name="DeferredTaxAssetsLiabilitiesGross" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant"/>
  <xsd:element id="poai_DeferredTaxAssetsNQSOCompensation" name="DeferredTaxAssetsNQSOCompensation" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant"/>
  <xsd:element id="poai_DeferredTaxAssetsOperatingLossCarryforwardsAndCredits" name="DeferredTaxAssetsOperatingLossCarryforwardsAndCredits" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant"/>
  <xsd:element id="poai_DeferredTaxAssetsRightOfUseAssets" name="DeferredTaxAssetsRightOfUseAssets" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant"/>
  <xsd:element id="poai_DeferredTaxLiabilitiesOriginalIssueDiscount" name="DeferredTaxLiabilitiesOriginalIssueDiscount" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant"/>
  <xsd:element id="poai_DefinedContributionPlanEmployerContributionAmount" name="DefinedContributionPlanEmployerContributionAmount" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_DemoEquipmentMember" name="DemoEquipmentMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_DemonstrationEquipmentMember" name="DemonstrationEquipmentMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_DerivativeLiabilityWriteOff" name="DerivativeLiabilityWriteOff" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element id="poai_DerivativesDebtIssued" name="DerivativesDebtIssued" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_DocumentAndEntityInformation" name="DocumentAndEntityInformation" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_DrSchwartzMember" name="DrSchwartzMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_DrSchwartzNoteOneMember" name="DrSchwartzNoteOneMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_DrSchwartzNotesWarrantsMember" name="DrSchwartzNotesWarrantsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_DrschwartzNotesMember" name="DrschwartzNotesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_EffectOfCovid19PandemicPolicyTextBlock" name="EffectOfCovid19PandemicPolicyTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_EffectiveIncomeTaxRateReconciliationAcquisitionAdjustmentAmount" name="EffectiveIncomeTaxRateReconciliationAcquisitionAdjustmentAmount" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element id="poai_EffectiveIncomeTaxRateReconciliationForeignIncomeTaxBenefitAmount" name="EffectiveIncomeTaxRateReconciliationForeignIncomeTaxBenefitAmount" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="poai_EffectiveIncomeTaxRateReconciliationOIDAndDerivativesAmount" name="EffectiveIncomeTaxRateReconciliationOIDAndDerivativesAmount" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element id="poai_EffectiveIncomeTaxRateReconciliationStateNetOperatingLossAdjustmentAmount" name="EffectiveIncomeTaxRateReconciliationStateNetOperatingLossAdjustmentAmount" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="poai_EffectiveIncomeTaxRateReconciliationStateTaxRateAdjustmentAmount" name="EffectiveIncomeTaxRateReconciliationStateTaxRateAdjustmentAmount" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element id="poai_EmbeddedDerivativeNoLongerBifurcatedAmountReclassifiedToStockholdersEquityOnExercise" name="EmbeddedDerivativeNoLongerBifurcatedAmountReclassifiedToStockholdersEquityOnExercise" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="poai_EquityInstrumentsIssuedForManagementAndConsulting" name="EquityInstrumentsIssuedForManagementAndConsulting" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_EquityLinePurchaseAgreementMember" name="EquityLinePurchaseAgreementMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_EquityMethodInvestmentOwnershipPercentagePurchasedDuringPeriod" name="EquityMethodInvestmentOwnershipPercentagePurchasedDuringPeriod" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_EstimatedUsefulLifeByAssetClassificationTableTextBlock" name="EstimatedUsefulLifeByAssetClassificationTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_February162021RegisteredDirectOfferingMember" name="February162021RegisteredDirectOfferingMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_Febuary232021PrivatePlacementMember" name="Febuary232021PrivatePlacementMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_FixedAssetsAcquiredForFinancingArrangements" name="FixedAssetsAcquiredForFinancingArrangements" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="poai_FixedAssetsAcquiredForNotesReceivableAndCommonStock" name="FixedAssetsAcquiredForNotesReceivableAndCommonStock" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="poai_ForebearanaceSettlementOnBridgeLoan" name="ForebearanaceSettlementOnBridgeLoan" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="poai_GainLossOnNoteReceivableAssetPurchaseAgreement" name="GainLossOnNoteReceivableAssetPurchaseAgreement" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="poai_GainLossOnReceivablePreviouslyConsideredUncollectable" name="GainLossOnReceivablePreviouslyConsideredUncollectable" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="poai_GainLossOnRevaluationOfEquityMethodInvestment" name="GainLossOnRevaluationOfEquityMethodInvestment" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="poai_GainLossesOnDebtRevaluation" name="GainLossesOnDebtRevaluation" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="poai_GoodwillDecreaseInGrowthRateOf05PercentReductionInFairValue" name="GoodwillDecreaseInGrowthRateOf05PercentReductionInFairValue" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element id="poai_GoodwillIncreaseInDiscountRateOf05PercentReductionInFairValue" name="GoodwillIncreaseInDiscountRateOf05PercentReductionInFairValue" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_HelomicsHoldingCorpMember" name="HelomicsHoldingCorpMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_HelomicsOfficesLeaseAreaForLaboratoryMember" name="HelomicsOfficesLeaseAreaForLaboratoryMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_HelomicsOfficesLeaseAreaForOfficeSpaceMember" name="HelomicsOfficesLeaseAreaForOfficeSpaceMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_HelomicsOfficesMember" name="HelomicsOfficesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_HelomicsSegmentMember" name="HelomicsSegmentMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" 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 abstract="true" id="poai_InvestorOfPromissoryNoteMember" name="InvestorOfPromissoryNoteMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_InvestorWarrantsMember" name="InvestorWarrantsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_IssuanceOfSharesAndPrefundedWarrantsPursuantToPrivatePlacementValue" name="IssuanceOfSharesAndPrefundedWarrantsPursuantToPrivatePlacementValue" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" 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="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_January212021RegisteredDirectOfferingMember" name="January212021RegisteredDirectOfferingMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_January262021RegisteredDirectOfferingMember" name="January262021RegisteredDirectOfferingMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_June2020WarrantMember" name="June2020WarrantMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_LaboratoryEquipmentMember" name="LaboratoryEquipmentMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_ManufacturingAndLaboratoryEquipmentMember" name="ManufacturingAndLaboratoryEquipmentMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_ManufacturingToolingMember" name="ManufacturingToolingMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_MaturityExtensionToMarch312021Member" name="MaturityExtensionToMarch312021Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_May2020OfferingMember" name="May2020OfferingMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_MeasurementInputExpectedCashFlowTermMember" name="MeasurementInputExpectedCashFlowTermMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_MeasurementInputRiskPremiumMember" name="MeasurementInputRiskPremiumMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_NewWarrantsFromExerciseOfWarrantsMember" name="NewWarrantsFromExerciseOfWarrantsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum: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_NotesAssumedFromAcquisitonMember" name="NotesAssumedFromAcquisitonMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_NotesIssuedToHelomicsNoteholdersMember" name="NotesIssuedToHelomicsNoteholdersMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_NotesReceivableInterestRateStatedPercentage" name="NotesReceivableInterestRateStatedPercentage" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant"/>
  <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_OfferingCostsPolicyTextBlock" name="OfferingCostsPolicyTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_OtherExpensePolicyPolicyTextBlock" name="OtherExpensePolicyPolicyTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_PatentsAndTrademarksMember" name="PatentsAndTrademarksMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_PaycheckProtectionProgramCaresActMember" name="PaycheckProtectionProgramCaresActMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum: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 id="poai_PenaltiesAccrued" name="PenaltiesAccrued" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant"/>
  <xsd:element abstract="true" id="poai_PlacementAgentWarrantsMember" name="PlacementAgentWarrantsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_PreferredStockBeneficialConversionFeature" name="PreferredStockBeneficialConversionFeature" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_PrefundedWarrantMember" name="PrefundedWarrantMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_PriceOfWarrant" name="PriceOfWarrant" nillable="true" substitutionGroup="xbrli:item" type="num:perShareItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_ProceedsFromIssuanceAndExerciseOfWarrants" name="ProceedsFromIssuanceAndExerciseOfWarrants" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element id="poai_ProceedsFromIssuanceAndExerciseOfWarrantsNet" name="ProceedsFromIssuanceAndExerciseOfWarrantsNet" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <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="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_PromissoryNote2019ConversionFeatureMember" name="PromissoryNote2019ConversionFeatureMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_PromissoryNote20202Member" name="PromissoryNote20202Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_PromissoryNote2020ConversionFeatureMember" name="PromissoryNote2020ConversionFeatureMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_PromissoryNote2020ConversionFeatureTrancheOneMember" name="PromissoryNote2020ConversionFeatureTrancheOneMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_PromissoryNote2020ConversionFeatureTrancheThreeMember" name="PromissoryNote2020ConversionFeatureTrancheThreeMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_PromissoryNote2020ConversionFeatureTrancheTwoMember" name="PromissoryNote2020ConversionFeatureTrancheTwoMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_PromissoryNote2020Member" name="PromissoryNote2020Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_PromissoryNoteExchangeAgreementMember" name="PromissoryNoteExchangeAgreementMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_PromissoryNoteMember" name="PromissoryNoteMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_PromissoryNoteOneMember" name="PromissoryNoteOneMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_PromissoryNoteTwoMember" name="PromissoryNoteTwoMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_PromissoryNotesReceivableMember" name="PromissoryNotesReceivableMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_PropertyPlantAndEquipmentUsefulLifeTableTextBlock" name="PropertyPlantAndEquipmentUsefulLifeTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_PurchaseAgreementTerm" name="PurchaseAgreementTerm" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_ReductionToLoanDueToCumulativeEquityMethodInvestmentLossesIncurred" name="ReductionToLoanDueToCumulativeEquityMethodInvestmentLossesIncurred" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant"/>
  <xsd:element abstract="true" id="poai_RegisteredDirectOfferingMember" name="RegisteredDirectOfferingMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_RegisteredDirectOfferingsMember" name="RegisteredDirectOfferingsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_RelatedPartyTransactionMonthlyCashPayment" name="RelatedPartyTransactionMonthlyCashPayment" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant"/>
  <xsd:element id="poai_ReportingUnitMeasurementInput" name="ReportingUnitMeasurementInput" nillable="true" substitutionGroup="xbrli:item" type="xbrli:decimalItemType" xbrli:periodType="instant"/>
  <xsd:element abstract="true" id="poai_ReverseStockSplitMember" name="ReverseStockSplitMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_RightToPurchaseUnitsMember" name="RightToPurchaseUnitsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_RisksAndUncertaintiesPolicyPolicyTextBlock" name="RisksAndUncertaintiesPolicyPolicyTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_SaleOfStockAgentPlacementFeePercentOfGrossProceeds" name="SaleOfStockAgentPlacementFeePercentOfGrossProceeds" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant"/>
  <xsd:element id="poai_SaleOfStockManagementFeePercentOfGrossProceeds" name="SaleOfStockManagementFeePercentOfGrossProceeds" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant"/>
  <xsd:element id="poai_SaleOfStockPlacementAgentWarrantsAssignedNumberOfSecuritiesCalledByWarrantsPercentOfSharesSold" name="SaleOfStockPlacementAgentWarrantsAssignedNumberOfSecuritiesCalledByWarrantsPercentOfSharesSold" nillable="true" substitutionGroup="xbrli:item" type="num: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="nonnum:textBlockItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_ScheduleOfSharebasedCompensationSharesAuthorizedUnderStockOptionAndWarrantPlansByExercisePriceRangeTableTextBlock" name="ScheduleOfSharebasedCompensationSharesAuthorizedUnderStockOptionAndWarrantPlansByExercisePriceRangeTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_SecondPromissoryNoteMember" name="SecondPromissoryNoteMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_SecuritiesPurchaseAgreementsMember" name="SecuritiesPurchaseAgreementsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_SeriesAWarrantsMember" name="SeriesAWarrantsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_SeriesBConvertiblePreferredStockMember" name="SeriesBConvertiblePreferredStockMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_SeriesBWarrantsMember" name="SeriesBWarrantsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_SeriesDConvertiblePreferredStockMember" name="SeriesDConvertiblePreferredStockMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_SeriesEConvertiblePreferredStockMember" name="SeriesEConvertiblePreferredStockMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_SharePerEachUnit" name="SharePerEachUnit" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="instant"/>
  <xsd:element id="poai_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsExercisedWeightedAverageGrantDateFairValue" name="SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsExercisedWeightedAverageGrantDateFairValue" nillable="true" substitutionGroup="xbrli:item" type="num:perShareItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_SkylineMedicalEuropesOfficesLeaseMember" name="SkylineMedicalEuropesOfficesLeaseMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_SkylineMedicalEuropesOfficesLeaseOfficeSpaceMember" name="SkylineMedicalEuropesOfficesLeaseOfficeSpaceMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_SkylineMedicalEuropesOfficesLeaseStorageSpaceMember" name="SkylineMedicalEuropesOfficesLeaseStorageSpaceMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_SkylineMember" name="SkylineMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_SolubleBiodtechOfficesInBirminghamAlabamaMember" name="SolubleBiodtechOfficesInBirminghamAlabamaMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_SolubleMember" name="SolubleMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_StockIssuedAgreementNotToBeTransferredOrSoldForSixMonths" name="StockIssuedAgreementNotToBeTransferredOrSoldForSixMonths" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="instant"/>
  <xsd:element id="poai_StockIssuedAgreementNotToBeTransferredOrSoldForThreeMonths" name="StockIssuedAgreementNotToBeTransferredOrSoldForThreeMonths" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="instant"/>
  <xsd:element id="poai_StockIssuedDuringPeriodSharesConversionOfPreferredStock" name="StockIssuedDuringPeriodSharesConversionOfPreferredStock" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_StockIssuedDuringPeriodSharesConvertiblePreferredSharesIssued" name="StockIssuedDuringPeriodSharesConvertiblePreferredSharesIssued" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_StockIssuedDuringPeriodSharesExchangeAgreement" name="StockIssuedDuringPeriodSharesExchangeAgreement" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_StockIssuedDuringPeriodSharesExtensionOfNotesPayable" name="StockIssuedDuringPeriodSharesExtensionOfNotesPayable" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_StockIssuedDuringPeriodSharesExtinguishmentOfDebt" name="StockIssuedDuringPeriodSharesExtinguishmentOfDebt" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_StockIssuedDuringPeriodSharesForebearanceForBridgeLoan" name="StockIssuedDuringPeriodSharesForebearanceForBridgeLoan" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_StockIssuedDuringPeriodSharesInducementToConvertibleDebt" name="StockIssuedDuringPeriodSharesInducementToConvertibleDebt" 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_StockIssuedDuringPeriodSharesInducementToPrivatePlacement" name="StockIssuedDuringPeriodSharesInducementToPrivatePlacement" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_StockIssuedDuringPeriodSharesInducementToPromissoryNoteExtension" name="StockIssuedDuringPeriodSharesInducementToPromissoryNoteExtension" 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_StockIssuedDuringPeriodValueConvertiblePreferredSharesIssued" name="StockIssuedDuringPeriodValueConvertiblePreferredSharesIssued" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="poai_StockIssuedDuringPeriodValueExtinguishmentOfDebt" name="StockIssuedDuringPeriodValueExtinguishmentOfDebt" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="poai_StockIssuedDuringPeriodValueForebearanceForBridgeLoan" name="StockIssuedDuringPeriodValueForebearanceForBridgeLoan" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="poai_StockIssuedDuringPeriodValueInducementToConvertibleDebt" name="StockIssuedDuringPeriodValueInducementToConvertibleDebt" 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_StockIssuedDuringPeriodValueInducementToPromissoryNoteExtension" name="StockIssuedDuringPeriodValueInducementToPromissoryNoteExtension" 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_StockIssuedForConvertibleDebtMember" name="StockIssuedForConvertibleDebtMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_StockIssuedForDebtMember" name="StockIssuedForDebtMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_StockOptions2012Member" name="StockOptions2012Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_StockOptions2013Member" name="StockOptions2013Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_StockOptions2014Member" name="StockOptions2014Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_StockOptions2015Member" name="StockOptions2015Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_StockOptions2016Member" name="StockOptions2016Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_StockOptions2017Member" name="StockOptions2017Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_StockOptions2018Member" name="StockOptions2018Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_StockOptions2019Member" name="StockOptions2019Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_StockOptions2020Member" name="StockOptions2020Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_StockOptionsFourMember" name="StockOptionsFourMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_StockOptionsOneMember" name="StockOptionsOneMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_StockOptionsThreeMember" name="StockOptionsThreeMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_StockOptionsTwoMember" name="StockOptionsTwoMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_The2019OfferingMember" name="The2019OfferingMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_The2019OfferingWarrantsMember" name="The2019OfferingWarrantsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_TradeNames1Member" name="TradeNames1Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_UnitAgreementNumberOfSharesOfCommonStockIncludedInEachUnit" name="UnitAgreementNumberOfSharesOfCommonStockIncludedInEachUnit" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="instant"/>
  <xsd:element id="poai_UnitAgreementNumberOfWarrantsIncludedInEachUnit" name="UnitAgreementNumberOfWarrantsIncludedInEachUnit" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="instant"/>
  <xsd:element id="poai_ValuationAllowancePercentage" name="ValuationAllowancePercentage" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant"/>
  <xsd:element id="poai_ValuationAndAccountingForStockOptionsAndWarrantsPolicyPolicyTextBlock" name="ValuationAndAccountingForStockOptionsAndWarrantsPolicyPolicyTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_WarrantForPromissoryNotesMember" name="WarrantForPromissoryNotesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_WarrantFourMember" name="WarrantFourMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_WarrantIssuedInConnectionWithMay2020OfferingMember" name="WarrantIssuedInConnectionWithMay2020OfferingMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_WarrantOneMember" name="WarrantOneMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_WarrantThreeMember" name="WarrantThreeMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_WarrantTwoMember" name="WarrantTwoMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_Warrants2016Member" name="Warrants2016Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_Warrants2017Member" name="Warrants2017Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_Warrants2018Member" name="Warrants2018Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_Warrants2019Member" name="Warrants2019Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_Warrants2020Member" name="Warrants2020Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_WarrantsAndAgentWarrantsInConnectionWithJune2020WarrantMember" name="WarrantsAndAgentWarrantsInConnectionWithJune2020WarrantMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_WarrantsAndAgentWarrantsInConnectionWithMay2020WarrantMember" name="WarrantsAndAgentWarrantsInConnectionWithMay2020WarrantMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_WarrantsHeldByNoteholdersMember" name="WarrantsHeldByNoteholdersMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_WarrantsHeldByOtherPartiesMember" name="WarrantsHeldByOtherPartiesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_WarrantsIssued" name="WarrantsIssued" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="poai_WarrantsIssuedDebtIssuance" name="WarrantsIssuedDebtIssuance" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_WarrantsIssuedFor2019AgreementMember" name="WarrantsIssuedFor2019AgreementMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_WarrantsIssuedInConnectionWithHelomicsAcquisitionMember" name="WarrantsIssuedInConnectionWithHelomicsAcquisitionMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_WarrantsIssuedPursuantToConvertibleDebtMember" name="WarrantsIssuedPursuantToConvertibleDebtMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_WarrantsIssuedToCEOMember" name="WarrantsIssuedToCEOMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_WarrantsIssuedToHelomicsInvestorsMember" name="WarrantsIssuedToHelomicsInvestorsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_WarrantsIssuedToHoldersOfHelomicsNotesAndWarrantsMember" name="WarrantsIssuedToHoldersOfHelomicsNotesAndWarrantsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_WarrantsIssuedWithPrivatePlacementMember" name="WarrantsIssuedWithPrivatePlacementMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_WarrantsIssuedWithPromissoryNoteMember" name="WarrantsIssuedWithPromissoryNoteMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_WarrantsIssuedWithPromissoryNoteOneMember" name="WarrantsIssuedWithPromissoryNoteOneMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_WarrantsIssuedWithPromissoryNoteThreeMember" name="WarrantsIssuedWithPromissoryNoteThreeMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_WarrantsIssuedWithPromissoryNoteTwoMember" name="WarrantsIssuedWithPromissoryNoteTwoMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum: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-income-taxes-components-of-deferred-income-taxes-details" name="statement-statement-note-10-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-10-income-taxes-reconciliation-of-income-tax-benefit-expense-details" name="statement-statement-note-10-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-10-income-taxes-tables" name="statement-statement-note-10-income-taxes-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-11-goodwill-and-intangibles-components-of-intangible-assets-details" name="statement-statement-note-11-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-11-goodwill-and-intangibles-estimated-future-amortization-expense-details" name="statement-statement-note-11-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-11-goodwill-and-intangibles-goodwill-details" name="statement-statement-note-11-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-11-goodwill-and-intangibles-tables" name="statement-statement-note-11-goodwill-and-intangibles-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-12-leases-lease-information-details" name="statement-statement-note-12-leases-lease-information-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-12-leases-rent-obligation-details" name="statement-statement-note-12-leases-rent-obligation-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-12-leases-tables" name="statement-statement-note-12-leases-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-13-property-plant-and-equipment-schedule-of-property-plant-and-equipment-details" name="statement-statement-note-13-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-13-property-plant-and-equipment-schedule-of-property-plant-and-equipment-useful-life-details" name="statement-statement-note-13-property-plant-and-equipment-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-13-property-plant-and-equipment-tables" name="statement-statement-note-13-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-14-segments-segments-details" name="statement-statement-note-14-segments-segments-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-14-segments-tables" name="statement-statement-note-14-segments-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-17-subsequent-events-stock-offerings-details" name="statement-statement-note-17-subsequent-events-stock-offerings-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-17-subsequent-events-tables" name="statement-statement-note-17-subsequent-events-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-2-helomics-acquisition-fair-value-of-assets-and-liabilities-assumed-details" name="statement-statement-note-2-helomics-acquisition-fair-value-of-assets-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-helomics-acquisition-pro-forma-information-details" name="statement-statement-note-2-helomics-acquisition-pro-forma-information-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-2-helomics-acquisition-tables" name="statement-statement-note-2-helomics-acquisition-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-3-equity-method-investment-summary-of-equity-method-investments-details" name="statement-statement-note-3-equity-method-investment-summary-of-equity-method-investments-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-3-equity-method-investment-tables" name="statement-statement-note-3-equity-method-investment-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-4-inventories-schedule-of-inventory-details" name="statement-statement-note-4-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-4-inventories-tables" name="statement-statement-note-4-inventories-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-5-stockholders-equity-stock-options-and-warrants-schedule-of-listing-of-stock-options-and-warrants-details" name="statement-statement-note-5-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-5-stockholders-equity-stock-options-and-warrants-summary-of-status-of-options-and-warrants-outstanding-details" name="statement-statement-note-5-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-5-stockholders-equity-stock-options-and-warrants-summary-of-transactions-for-stock-options-and-warrants-details" name="statement-statement-note-5-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-5-stockholders-equity-stock-options-and-warrants-tables" name="statement-statement-note-5-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-7-notes-payable-notes-payable-details" name="statement-statement-note-7-notes-payable-notes-payable-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-7-notes-payable-tables" name="statement-statement-note-7-notes-payable-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-8-derivatives-change-in-fair-value-of-derivative-liabilities-details" name="statement-statement-note-8-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-8-derivatives-tables" name="statement-statement-note-8-derivatives-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-9-loss-per-share-antidilutive-securities-excluded-from-the-diluted-calculations-details" name="statement-statement-note-9-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-9-loss-per-share-shares-used-in-basic-and-diluted-loss-per-common-share-computations-details" name="statement-statement-note-9-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-9-loss-per-share-tables" name="statement-statement-note-9-loss-per-share-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>
