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  <xsd:element abstract="true" id="bcrx_LongTermLiabilitiesMember" name="LongTermLiabilitiesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="bcrx_LongtermInvestmentMaturityMinimum" name="LongtermInvestmentMaturityMinimum" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration"/>
  <xsd:element id="bcrx_MaturityOfInvestments" name="MaturityOfInvestments" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration"/>
  <xsd:element id="bcrx_MaturityPeriodOfHighQualityMarketablesecurities" name="MaturityPeriodOfHighQualityMarketablesecurities" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration"/>
  <xsd:element id="bcrx_MaturityperiodOfShortTermInvestment" name="MaturityperiodOfShortTermInvestment" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration"/>
  <xsd:element id="bcrx_MaximumAggregateOfferingPrice" name="MaximumAggregateOfferingPrice" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant"/>
  <xsd:element id="bcrx_MaximumAmountOfCollateralRequiredToPost" name="MaximumAmountOfCollateralRequiredToPost" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant"/>
  <xsd:element id="bcrx_MilestonePaymentMaximum" name="MilestonePaymentMaximum" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element id="bcrx_MilestonePaymentMinimum" name="MilestonePaymentMinimum" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="bcrx_MundipharmaMember" name="MundipharmaMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="bcrx_NationalInstituteOfAllergyAndInfectiousDiseasesMember" name="NationalInstituteOfAllergyAndInfectiousDiseasesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="bcrx_NonEmployeeDirectorsMember" name="NonEmployeeDirectorsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="bcrx_NoteToFinancialStatementDetailsTextual" name="NoteToFinancialStatementDetailsTextual" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="bcrx_NotesToFinancialStatements" name="NotesToFinancialStatements" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="bcrx_NotesToFinancialStatementsAbstract" name="NotesToFinancialStatementsAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element id="bcrx_NumberOfMilestonesAchieved" name="NumberOfMilestonesAchieved" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="duration"/>
  <xsd:element id="bcrx_NumberOfStockbasedCompensationPlans" name="NumberOfStockbasedCompensationPlans" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="duration"/>
  <xsd:element id="bcrx_PaymentsForModificationOfLicenseAgreement" name="PaymentsForModificationOfLicenseAgreement" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element id="bcrx_PercentageOfCarryingAmountInExcessOfFairValue1" name="PercentageOfCarryingAmountInExcessOfFairValue1" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant"/>
  <xsd:element id="bcrx_PercentageOfCommonStockSharesBeginning" name="PercentageOfCommonStockSharesBeginning" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration"/>
  <xsd:element id="bcrx_PercentageOfCommonStockSharesEnding" name="PercentageOfCommonStockSharesEnding" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration"/>
  <xsd:element id="bcrx_PercentageOfSalaryToPurchaseCommonStockMaximum" name="PercentageOfSalaryToPurchaseCommonStockMaximum" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration"/>
  <xsd:element id="bcrx_PeriodOfAgreement" name="PeriodOfAgreement" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="bcrx_PhaRMANotesMember" name="PhaRMANotesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="bcrx_PotentialMilestonePaymentsReceivable" name="PotentialMilestonePaymentsReceivable" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant"/>
  <xsd:element id="bcrx_PrivatePlacementOfSeniorSecuredNotes" name="PrivatePlacementOfSeniorSecuredNotes" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element id="bcrx_ProceedsFromAwardsForResearchAndDevelopmentContracts" name="ProceedsFromAwardsForResearchAndDevelopmentContracts" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="bcrx_RAPIVABMember" name="RAPIVABMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="bcrx_ReceiptPaymentOfForeignCurrencyDerivativeCollateral" name="ReceiptPaymentOfForeignCurrencyDerivativeCollateral" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="bcrx_RegulatorySupportRevenueForCanadianAndEUMarketingApprovalsPortionRecognizedRatablyOverExpectedPeriodOfInvolvementMember" name="RegulatorySupportRevenueForCanadianAndEUMarketingApprovalsPortionRecognizedRatablyOverExpectedPeriodOfInvolvementMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="bcrx_RemainingAggregateOfferingPrice" name="RemainingAggregateOfferingPrice" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant"/>
  <xsd:element id="bcrx_RenewablePeriodOfAgreement" name="RenewablePeriodOfAgreement" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration"/>
  <xsd:element id="bcrx_RequiredForeignCurrencyHedgePerDollar" name="RequiredForeignCurrencyHedgePerDollar" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:periodType="instant"/>
  <xsd:element abstract="true" id="bcrx_RevenueFromSaleOfInventoryToBeRecognizedWhenTheInventoryTransferIsCompleteMember" name="RevenueFromSaleOfInventoryToBeRecognizedWhenTheInventoryTransferIsCompleteMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="bcrx_RevenueRecognitionRoyaltyAndMilestoneRevenueRecognizedNet" name="RevenueRecognitionRoyaltyAndMilestoneRevenueRecognizedNet" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element id="bcrx_RevenuerecognitionRoyaltyAndMilestoneRevenueRecognized" name="RevenuerecognitionRoyaltyAndMilestoneRevenueRecognized" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant"/>
  <xsd:element abstract="true" id="bcrx_RoyaltyMonetizationMember" name="RoyaltyMonetizationMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="bcrx_RoyaltyMonetizationTextBlock" name="RoyaltyMonetizationTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="bcrx_RoyaltyReceivableMember" name="RoyaltyReceivableMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="bcrx_RoyaltyTerm" name="RoyaltyTerm" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration"/>
  <xsd:element id="bcrx_ScheduleOfReceivablesFromCollaborationsTableTextBlock" name="ScheduleOfReceivablesFromCollaborationsTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration"/>
  <xsd:element id="bcrx_ScheduleOfRevenuesFromCollaborationsTableTextBlock" name="ScheduleOfRevenuesFromCollaborationsTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration"/>
  <xsd:element id="bcrx_SecuritiesOffered" name="SecuritiesOffered" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:periodType="duration"/>
  <xsd:element id="bcrx_ShareBasedCompensationArrangementBySharbasedPaymentAwardMaximumNumberOfSharesPerEmployeeAmount" name="ShareBasedCompensationArrangementBySharbasedPaymentAwardMaximumNumberOfSharesPerEmployeeAmount" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:periodType="instant"/>
  <xsd:element id="bcrx_ShareBasedCompensationArrangementByShareBasedPaymentAwardFirstVestingPeriodAfterGrantDate" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardFirstVestingPeriodAfterGrantDate" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration"/>
  <xsd:element id="bcrx_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodAwardsAvailable" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodAwardsAvailable" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration"/>
  <xsd:element id="bcrx_SharebasedCompensationArrangementBySharbasedPaymentAwardAwardsUnvestedPercentage" name="SharebasedCompensationArrangementBySharbasedPaymentAwardAwardsUnvestedPercentage" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration"/>
  <xsd:element id="bcrx_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsForfeituresInPeriodAwardsAvailable" name="SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsForfeituresInPeriodAwardsAvailable" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="bcrx_ShionogiAndCoLtdMember" name="ShionogiAndCoLtdMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="bcrx_Shortfall2013Member" name="Shortfall2013Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="bcrx_StockIssuedDuringPeriodSharesForOverAllotmentOptionExercisedByUnderwriter" name="StockIssuedDuringPeriodSharesForOverAllotmentOptionExercisedByUnderwriter" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration"/>
  <xsd:element id="bcrx_StockIssuedDuringPeriodValueForModificationOfLicenseAgreement" name="StockIssuedDuringPeriodValueForModificationOfLicenseAgreement" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="bcrx_StockOptionsAndRestrictedStockMember" name="StockOptionsAndRestrictedStockMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="bcrx_TransactionCosts" name="TransactionCosts" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="bcrx_UABMember" name="UABMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="bcrx_USDepartmentOfHealthAndHumanServicesMember" name="USDepartmentOfHealthAndHumanServicesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="bcrx_UpfrontPaymentMember" name="UpfrontPaymentMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="bcrx_UpfrontPaymentsReceivableAmount" name="UpfrontPaymentsReceivableAmount" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="bcrx_Vest25PercentEachYearUntilFullyVestedMember" name="Vest25PercentEachYearUntilFullyVestedMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="bcrx_Vest50PercentEachYearUntilFullyVestedMember" name="Vest50PercentEachYearUntilFullyVestedMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="bcrx_VestUponSuccessfulCompletionOfSpecificDevelopmentMilestonesMember" name="VestUponSuccessfulCompletionOfSpecificDevelopmentMilestonesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="bcrx_statement-statement-note-1-accrued-expenses-details" name="statement-statement-note-1-accrued-expenses-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="bcrx_statement-statement-note-1-fair-value-of-the-companys-investments-by-type-details" name="statement-statement-note-1-fair-value-of-the-companys-investments-by-type-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="bcrx_statement-statement-note-1-inventory-details" name="statement-statement-note-1-inventory-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="bcrx_statement-statement-note-1-scheduled-maturity-for-the-companys-investments-details" name="statement-statement-note-1-scheduled-maturity-for-the-companys-investments-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="bcrx_statement-statement-note-1-significant-accounting-policies-and-concentrations-of-risk-tables" name="statement-statement-note-1-significant-accounting-policies-and-concentrations-of-risk-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="bcrx_statement-statement-note-1-summary-of-receivables-details" name="statement-statement-note-1-summary-of-receivables-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="bcrx_statement-statement-note-1-summary-of-revenues-details" name="statement-statement-note-1-summary-of-revenues-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="bcrx_statement-statement-note-10-quarterly-financial-information-unaudited-details" name="statement-statement-note-10-quarterly-financial-information-unaudited-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="bcrx_statement-statement-note-10-quarterly-financial-information-unaudited-tables" name="statement-statement-note-10-quarterly-financial-information-unaudited-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="bcrx_statement-statement-note-2-furniture-and-equipment-details" name="statement-statement-note-2-furniture-and-equipment-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="bcrx_statement-statement-note-2-furniture-and-equipment-tables" name="statement-statement-note-2-furniture-and-equipment-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="bcrx_statement-statement-note-4-lease-obligations-and-other-contingencies-tables" name="statement-statement-note-4-lease-obligations-and-other-contingencies-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="bcrx_statement-statement-note-4-minimum-payments-under-operating-lease-obligations-details" name="statement-statement-note-4-minimum-payments-under-operating-lease-obligations-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="bcrx_statement-statement-note-6-changes-in-the-number-and-weightedaverage-grantdate-fair-value-details" name="statement-statement-note-6-changes-in-the-number-and-weightedaverage-grantdate-fair-value-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="bcrx_statement-statement-note-6-number-of-stock-option-awards-exercisable-and-their-weighted-average-exercise-price-details" name="statement-statement-note-6-number-of-stock-option-awards-exercisable-and-their-weighted-average-exercise-price-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="bcrx_statement-statement-note-6-stock-incentive-plan-activities-details" name="statement-statement-note-6-stock-incentive-plan-activities-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="bcrx_statement-statement-note-6-stockbased-compensation-allocation-details" name="statement-statement-note-6-stockbased-compensation-allocation-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="bcrx_statement-statement-note-6-stockbased-compensation-tables" name="statement-statement-note-6-stockbased-compensation-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="bcrx_statement-statement-note-6-weighted-average-assumptions-for-stock-option-awards-granted-to-employees-and-directors-under-the-incentive-plan-details" name="statement-statement-note-6-weighted-average-assumptions-for-stock-option-awards-granted-to-employees-and-directors-under-the-incentive-plan-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="bcrx_statement-statement-note-7-components-of-deferred-tax-assets-and-liabilities-details" name="statement-statement-note-7-components-of-deferred-tax-assets-and-liabilities-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="bcrx_statement-statement-note-7-differences-between-the-companys-effective-tax-rate-and-the-statutory-tax-rate-details" name="statement-statement-note-7-differences-between-the-companys-effective-tax-rate-and-the-statutory-tax-rate-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="bcrx_statement-statement-note-7-differences-between-the-companys-effective-tax-rate-and-the-statutory-tax-rate-details-parentheticals" name="statement-statement-note-7-differences-between-the-companys-effective-tax-rate-and-the-statutory-tax-rate-details-parentheticals" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="bcrx_statement-statement-note-7-income-taxes-tables" name="statement-statement-note-7-income-taxes-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="bcrx_statement-statement-note-7-reconciliation-of-beginning-and-ending-amount-of-unrecognized-tax-benefits-details" name="statement-statement-note-7-reconciliation-of-beginning-and-ending-amount-of-unrecognized-tax-benefits-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="bcrx_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>
