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    <import namespace="http://fasb.org/srt-types/2026" schemaLocation="https://xbrl.fasb.org/srt/2026/elts/srt-types-2026.xsd" />
    <element id="posc_SeriesAPreferredStocksMember" name="SeriesAPreferredStocksMember" nillable="true" xbrli:periodType="duration" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" />
    <element id="posc_SeriesBPreferredStocksMember" name="SeriesBPreferredStocksMember" nillable="true" xbrli:periodType="duration" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" />
    <element id="posc_OtherMember" name="OtherMember" nillable="true" xbrli:periodType="duration" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" />
    <element id="posc_StockOptionsMember" name="StockOptionsMember" nillable="true" xbrli:periodType="duration" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" />
    <element id="posc_CommonStocksMember" name="CommonStocksMember" nillable="true" xbrli:periodType="duration" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" />
    <element id="posc_ShareholderAndDirectorMember" name="ShareholderAndDirectorMember" nillable="true" xbrli:periodType="duration" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" />
    <element id="posc_NotePayable1RelatedPartyMember" name="NotePayable1RelatedPartyMember" nillable="true" xbrli:periodType="duration" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" />
    <element id="posc_NotePayable2RelatedPartyMember" name="NotePayable2RelatedPartyMember" nillable="true" xbrli:periodType="duration" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" />
    <element id="posc_NotePayable3RelatedPartyMember" name="NotePayable3RelatedPartyMember" nillable="true" xbrli:periodType="duration" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" />
    <element id="posc_NotePayable4RelatedPartyMember" name="NotePayable4RelatedPartyMember" nillable="true" xbrli:periodType="duration" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" />
    <element id="posc_WarrantsMember" name="WarrantsMember" nillable="true" xbrli:periodType="duration" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" />
    <element id="posc_FirstThreeYearsMember" name="FirstThreeYearsMember" nillable="true" xbrli:periodType="duration" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" />
    <element id="posc_LastTwoYearsMember" name="LastTwoYearsMember" nillable="true" xbrli:periodType="duration" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" />
    <element id="posc_SeriesSPreferredStockMember" name="SeriesSPreferredStockMember" nillable="true" xbrli:periodType="duration" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" />
    <element id="posc_ServicesMember" name="ServicesMember" nillable="true" xbrli:periodType="duration" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" />
    <element id="posc_CashPaymentsMember" name="CashPaymentsMember" nillable="true" xbrli:periodType="duration" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" />
    <element id="posc_PrincipalStockholderMember" name="PrincipalStockholderMember" nillable="true" xbrli:periodType="duration" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" />
    <element id="posc_BoardOfDirectorsChairmanAndPresidentMember" name="BoardOfDirectorsChairmanAndPresidentMember" nillable="true" xbrli:periodType="duration" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" />
    <element id="posc_BoardsOfDirectorsMember" name="BoardsOfDirectorsMember" nillable="true" xbrli:periodType="duration" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" />
    <element id="posc_InterestIncome" name="InterestIncome" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="posc_ImputedInterestExpenseOnDebtRelatedParties" name="ImputedInterestExpenseOnDebtRelatedParties" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="posc_AmortizationOfOperatingLeaseRightofuseAsset" name="AmortizationOfOperatingLeaseRightofuseAsset" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="posc_ImputedInterestExpenseOnDebtRelatedParty" name="ImputedInterestExpenseOnDebtRelatedParty" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="posc_PaymentsForRepurchaseOfCommonStocks" name="PaymentsForRepurchaseOfCommonStocks" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="posc_IncomeTaxPaidNet" name="IncomeTaxPaidNet" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="posc_ForgivenessOfAccruedInterestPayableRelatedParty" name="ForgivenessOfAccruedInterestPayableRelatedParty" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="posc_DisclosureConvertibleAdvancePayableAbstract" name="DisclosureConvertibleAdvancePayableAbstract" abstract="true" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="posc_ConvertibleAdvancesPayableTextBlock" name="ConvertibleAdvancesPayableTextBlock" nillable="true" xbrli:periodType="duration" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" />
    <element id="posc_DisclosureStockOptionPlanAbstract" name="DisclosureStockOptionPlanAbstract" abstract="true" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="posc_StockOptionsDisclosureTextBlock" name="StockOptionsDisclosureTextBlock" nillable="true" xbrli:periodType="duration" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" />
    <element id="posc_DisclosureWarrantsAbstract" name="DisclosureWarrantsAbstract" abstract="true" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="posc_WarrantsDisclosureTextBlock" name="WarrantsDisclosureTextBlock" nillable="true" xbrli:periodType="duration" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" />
    <element id="posc_DepositsPolicyTextBlock" name="DepositsPolicyTextBlock" nillable="true" xbrli:periodType="duration" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" />
    <element id="posc_ConcentrationsPolicyTextBlock" name="ConcentrationsPolicyTextBlock" nillable="true" xbrli:periodType="duration" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" />
    <element id="posc_FinancialInstrumentsWithCharacteristicsOfBothLiabilitiesAndEquityPolicyTextBlock" name="FinancialInstrumentsWithCharacteristicsOfBothLiabilitiesAndEquityPolicyTextBlock" nillable="true" xbrli:periodType="duration" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" />
    <element id="posc_OriginalIssueDiscountsAndOtherDebtDiscountsPolicyTextBlock" name="OriginalIssueDiscountsAndOtherDebtDiscountsPolicyTextBlock" nillable="true" xbrli:periodType="duration" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" />
    <element id="posc_WarrantyObligationsPolicyTextBlock" name="WarrantyObligationsPolicyTextBlock" nillable="true" xbrli:periodType="duration" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" />
    <element id="posc_TreasuryStockPolicyTextBlock" name="TreasuryStockPolicyTextBlock" nillable="true" xbrli:periodType="duration" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" />
    <element id="posc_RightOfUseAssetsAndLeaseObligationsPolicyTextBlock" name="RightOfUseAssetsAndLeaseObligationsPolicyTextBlock" nillable="true" xbrli:periodType="duration" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" />
    <element id="posc_ValuationOfDeferredTaxAssetsPolicyTextBlock" name="ValuationOfDeferredTaxAssetsPolicyTextBlock" nillable="true" xbrli:periodType="duration" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" />
    <element id="posc_StockWarrantsPolicyTextBlock" name="StockWarrantsPolicyTextBlock" nillable="true" xbrli:periodType="duration" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" />
    <element id="posc_BasicAndDilutedEarningsLossPerSharePolicyTextBlock" name="BasicAndDilutedEarningsLossPerSharePolicyTextBlock" nillable="true" xbrli:periodType="duration" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" />
    <element id="posc_PreferredStockClassificationPolicyTextBlock" name="PreferredStockClassificationPolicyTextBlock" nillable="true" xbrli:periodType="duration" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" />
    <element id="posc_RelatedPartiesPolicyTextBlock" name="RelatedPartiesPolicyTextBlock" nillable="true" xbrli:periodType="duration" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" />
    <element id="posc_ScheduleOfDepositsTableTextBlock" name="ScheduleOfDepositsTableTextBlock" nillable="true" xbrli:periodType="duration" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" />
    <element id="posc_ScheduleofMarketingandAdvertisingCostsTableTextBlock" name="ScheduleofMarketingandAdvertisingCostsTableTextBlock" nillable="true" xbrli:periodType="duration" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" />
    <element id="posc_ScheduleOfDilutiveEquitySecuritiesOutstandingTableTextBlock" name="ScheduleOfDilutiveEquitySecuritiesOutstandingTableTextBlock" nillable="true" xbrli:periodType="duration" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" />
    <element id="posc_ScheduleOfDepreciationExpenseTableTextBlock" name="ScheduleOfDepreciationExpenseTableTextBlock" nillable="true" xbrli:periodType="duration" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" />
    <element id="posc_ScheduleofConvertibleAdvancePayableTableTextBlock" name="ScheduleofConvertibleAdvancePayableTableTextBlock" nillable="true" xbrli:periodType="duration" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" />
    <element id="posc_SummaryofNotesPayabletoRelatedPartyTableTextBlock" name="SummaryofNotesPayabletoRelatedPartyTableTextBlock" nillable="true" xbrli:periodType="duration" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" />
    <element id="posc_ScheduleOfLossOnLeaseTerminationTableTextBlock" name="ScheduleOfLossOnLeaseTerminationTableTextBlock" nillable="true" xbrli:periodType="duration" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" />
    <element id="posc_ScheduleOfLesseeOperatingLeaseAssetsAndLiabilitiesTableTextBlock" name="ScheduleOfLesseeOperatingLeaseAssetsAndLiabilitiesTableTextBlock" nillable="true" xbrli:periodType="duration" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" />
    <element id="posc_OperatingLeaseLeaseExpenseTableTextBlock" name="OperatingLeaseLeaseExpenseTableTextBlock" nillable="true" xbrli:periodType="duration" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" />
    <element id="posc_WorkingCapitalDeficit" name="WorkingCapitalDeficit" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="posc_DepositsActivity" name="DepositsActivity" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="posc_RevenuesPercentage" name="RevenuesPercentage" nillable="true" xbrli:periodType="duration" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" />
    <element id="posc_TotalCommonStockEquivalents" name="TotalCommonStockEquivalents" nillable="true" xbrli:periodType="duration" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" />
    <element id="posc_AllowanceForExpectedCreditLosses" name="AllowanceForExpectedCreditLosses" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="posc_AdditionalEquipmentCostsToReadyUnitForSale" name="AdditionalEquipmentCostsToReadyUnitForSale" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="posc_InitialDeposits" name="InitialDeposits" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="posc_MaintenanceContractAmountsRemainingDeferred" name="MaintenanceContractAmountsRemainingDeferred" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="posc_IssuanceDateOfAdvances" name="IssuanceDateOfAdvances" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="posc_DebtMaturityDate" name="DebtMaturityDate" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="posc_DebtInstrumentInterestRateStatedPercentage1" name="DebtInstrumentInterestRateStatedPercentage1" nillable="true" xbrli:periodType="instant" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" />
    <element id="posc_CollateralForConvertableAdvancePayable" name="CollateralForConvertableAdvancePayable" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="posc_ConvertibleAdvancePayableBeginning" name="ConvertibleAdvancePayableBeginning" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="posc_ConvertibleAdvancePayableEnding" name="ConvertibleAdvancePayableEnding" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="posc_AdvancePayable" name="AdvancePayable" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="posc_DebtInstrumentMaturityDateDescription1" name="DebtInstrumentMaturityDateDescription1" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="posc_DebtInstrumentImputedInterestExpenseRatePercentage" name="DebtInstrumentImputedInterestExpenseRatePercentage" nillable="true" xbrli:periodType="instant" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" />
    <element id="posc_DebtInstrumentDefaultInterestRatePercentage" name="DebtInstrumentDefaultInterestRatePercentage" nillable="true" xbrli:periodType="instant" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" />
    <element id="posc_NotesPayableRelatedPartiesCurrent" name="NotesPayableRelatedPartiesCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="posc_DebtInstrumentsInterestRateStatedPercentage" name="DebtInstrumentsInterestRateStatedPercentage" nillable="true" xbrli:periodType="instant" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" />
    <element id="posc_DebtInstrumentsDefaultInterestRatePercentage" name="DebtInstrumentsDefaultInterestRatePercentage" nillable="true" xbrli:periodType="instant" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" />
    <element id="posc_DebtInstrumentPrincipalRepayment" name="DebtInstrumentPrincipalRepayment" nillable="true" xbrli:periodType="instant" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" />
    <element id="posc_DebtInstrumentAccruedInterest" name="DebtInstrumentAccruedInterest" nillable="true" xbrli:periodType="instant" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" />
    <element id="posc_WarrantExercisePrice" name="WarrantExercisePrice" nillable="true" xbrli:periodType="duration" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" />
    <element id="posc_DebtInstrumentsImputedInterestExpenseRatePercentage" name="DebtInstrumentsImputedInterestExpenseRatePercentage" nillable="true" xbrli:periodType="instant" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" />
    <element id="posc_DebtInstrumentImputedInterestExpenseRateAmount" name="DebtInstrumentImputedInterestExpenseRateAmount" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="posc_CashPaidToTerminateLease" name="CashPaidToTerminateLease" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="posc_OperatingLeaseLiabilities" name="OperatingLeaseLiabilities" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="posc_LossOnTerminationOfLease" name="LossOnTerminationOfLease" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="posc_TotalOperatingLeaseCosts" name="TotalOperatingLeaseCosts" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="posc_OperatingLeasesFutureMinimumPaymentDueThereafter" name="OperatingLeasesFutureMinimumPaymentDueThereafter" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="posc_OperatingLeasesLiability" name="OperatingLeasesLiability" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="posc_OperatingLeaseCommencementDate" name="OperatingLeaseCommencementDate" nillable="true" xbrli:periodType="duration" type="xbrli:dateItemType" substitutionGroup="xbrli:item" />
    <element id="posc_OperatingLeaseExpirationDate" name="OperatingLeaseExpirationDate" nillable="true" xbrli:periodType="duration" type="xbrli:dateItemType" substitutionGroup="xbrli:item" />
    <element id="posc_OperatingLeaseTermOfContract" name="OperatingLeaseTermOfContract" nillable="true" xbrli:periodType="duration" type="xbrli:durationItemType" substitutionGroup="xbrli:item" />
    <element id="posc_OperatingLeaseTerminationCost" name="OperatingLeaseTerminationCost" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="posc_DesignatedPreferredStockSharesAuthorized" name="DesignatedPreferredStockSharesAuthorized" nillable="true" xbrli:periodType="instant" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" />
    <element id="posc_PreferredStockDividendRights" name="PreferredStockDividendRights" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="posc_PreferredStockLiquidationPreferences" name="PreferredStockLiquidationPreferences" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="posc_PreferredStockRedemptionRights" name="PreferredStockRedemptionRights" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="posc_WarrantsIssued" name="WarrantsIssued" nillable="true" xbrli:periodType="instant" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" />
    <element id="posc_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsGrantedWeightedAverageRemainingContractualTerm2" name="SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsGrantedWeightedAverageRemainingContractualTerm2" nillable="true" xbrli:periodType="duration" type="xbrli:durationItemType" substitutionGroup="xbrli:item" />
    <element id="posc_WeightedAverageGrantDateFairValuePriceGranted" name="WeightedAverageGrantDateFairValuePriceGranted" nillable="true" xbrli:periodType="duration" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" />
    <element id="posc_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedWeightedAverageRemainingContractualTerm2" name="SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedWeightedAverageRemainingContractualTerm2" nillable="true" xbrli:periodType="duration" type="xbrli:durationItemType" substitutionGroup="xbrli:item" />
    <element id="posc_SharesAuthorizedUnderEquityIncentivePlan" name="SharesAuthorizedUnderEquityIncentivePlan" nillable="true" xbrli:periodType="instant" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" />
    <element id="posc_ShareBasedCompensationArrangementByShareBasedPaymentAwardExercisePrice" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardExercisePrice" nillable="true" xbrli:periodType="instant" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" />
    <element id="posc_ShareBasedCompensationArrangementByShareBasedPaymentAwardContractualTerm" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardContractualTerm" nillable="true" xbrli:periodType="duration" type="xbrli:durationItemType" substitutionGroup="xbrli:item" />
    <element id="posc_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesGranted" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesGranted" nillable="true" xbrli:periodType="instant" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" />
    <element id="posc_WeightedAverageRemainingContractualTermYearsOutstanding" name="WeightedAverageRemainingContractualTermYearsOutstanding" nillable="true" xbrli:periodType="duration" type="xbrli:durationItemType" substitutionGroup="xbrli:item" />
    <element id="posc_NumberOfWarrantsExercisable" name="NumberOfWarrantsExercisable" nillable="true" xbrli:periodType="instant" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" />
    <element id="posc_WeightedaverageexercisePriceExercisable" name="WeightedaverageexercisePriceExercisable" nillable="true" xbrli:periodType="instant" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" />
    <element id="posc_WeightedAverageRemainingContractualTermYearsExercisable" name="WeightedAverageRemainingContractualTermYearsExercisable" nillable="true" xbrli:periodType="duration" type="xbrli:durationItemType" substitutionGroup="xbrli:item" />
    <element id="posc_WarrantsAndRightsExercisable" name="WarrantsAndRightsExercisable" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="posc_NumberOfWarrantsGranted" name="NumberOfWarrantsGranted" nillable="true" xbrli:periodType="duration" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" />
    <element id="posc_WeightedaverageexercisePriceGranted" name="WeightedaverageexercisePriceGranted" nillable="true" xbrli:periodType="duration" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" />
    <element id="posc_NumberOfWarrantsExercised" name="NumberOfWarrantsExercised" nillable="true" xbrli:periodType="duration" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" />
    <element id="posc_NumberOfWarrantsCancelledforfeited" name="NumberOfWarrantsCancelledforfeited" nillable="true" xbrli:periodType="duration" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" />
    <element id="posc_WarrantsDescription" name="WarrantsDescription" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="posc_ClassOfWarrantOrRightIssuedDuringPeriod" name="ClassOfWarrantOrRightIssuedDuringPeriod" nillable="true" xbrli:periodType="instant" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" />
    <element id="posc_ExerciseOfPreviouslyIssuedWarrantsDescription" name="ExerciseOfPreviouslyIssuedWarrantsDescription" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="posc_NotePayableRelatedPartyMember" name="NotePayableRelatedPartyMember" nillable="true" xbrli:periodType="duration" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" />
    <element id="posc_DiscountInDebtToRelatedParty" name="DiscountInDebtToRelatedParty" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="posc_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights" name="ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights" nillable="true" xbrli:periodType="instant" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" />
</schema>
