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  <xsd:element abstract="true" id="sibn_OptionsTrancheTwoMember" name="OptionsTrancheTwoMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="sibn_PeriodOneMember" name="PeriodOneMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="sibn_PeriodThreeMember" name="PeriodThreeMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="sibn_PeriodTwoMember" name="PeriodTwoMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="sibn_PharmakonTermLoanMember" name="PharmakonTermLoanMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="sibn_PrepaymentPenalty3148MonthsMember" name="PrepaymentPenalty3148MonthsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="sibn_PrepaymentPenalty4960MonthsMember" name="PrepaymentPenalty4960MonthsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="sibn_RelatedPartyTransactionMonthlyPaymentsDueToRelatedPartyPerAgreement" name="RelatedPartyTransactionMonthlyPaymentsDueToRelatedPartyPerAgreement" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="sibn_RelatedPartyTransactionTermOfAgreement" name="RelatedPartyTransactionTermOfAgreement" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element id="sibn_RevenueRecognitionStandardPaymentTerms" name="RevenueRecognitionStandardPaymentTerms" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element id="sibn_SalesCreditReservePeriod" name="SalesCreditReservePeriod" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element id="sibn_ScheduleOfDebtCovenantEBITDAAndNetRevenueTargetsTableTextBlock" name="ScheduleOfDebtCovenantEBITDAAndNetRevenueTargetsTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="sibn_SecondaryOfferingMember" name="SecondaryOfferingMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="sibn_ShareBasedCompensationArrangementByShareBasedPaymentAwardAnnualIncreaseInSharesReservedAsPercentageOfPriorYearSharesOutstanding" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardAnnualIncreaseInSharesReservedAsPercentageOfPriorYearSharesOutstanding" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="sibn_ShareBasedCompensationArrangementByShareBasedPaymentAwardAnnualIncreaseInSharesReservedMaximumShares" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardAnnualIncreaseInSharesReservedMaximumShares" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="instant" />
  <xsd:element id="sibn_ShareBasedCompensationArrangementByShareBasedPaymentAwardExpirationPeriodForIndividualOwningMoreThanTenPercentOfOutstandingShares" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardExpirationPeriodForIndividualOwningMoreThanTenPercentOfOutstandingShares" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element id="sibn_ShareBasedCompensationArrangementByShareBasedPaymentAwardOfferingPeriodInterval" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOfferingPeriodInterval" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element id="sibn_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsEarlyExerciseCommonStockSubjectToRepurchase" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsEarlyExerciseCommonStockSubjectToRepurchase" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="instant" />
  <xsd:element id="sibn_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisePriceAsPercentOfFairMarketValue" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisePriceAsPercentOfFairMarketValue" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="sibn_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisePriceAsPercentOfFairMarketValueForIndividualOwningMoreThanTenPercentOfOutstandingShares" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisePriceAsPercentOfFairMarketValueForIndividualOwningMoreThanTenPercentOfOutstandingShares" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="sibn_ShareSubjectToRepurchaseMember" name="ShareSubjectToRepurchaseMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="sibn_StandardProductWarrantyTerm" name="StandardProductWarrantyTerm" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element id="sibn_StockIssuedDuringPeriodAmountRestrictedStockUnits" name="StockIssuedDuringPeriodAmountRestrictedStockUnits" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="sibn_StockIssuedDuringPeriodSharesRestrictedStockUnits" name="StockIssuedDuringPeriodSharesRestrictedStockUnits" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration" />
  <xsd:element id="sibn_StockIssuedDuringPeriodSharesUnvestedStockOptionsExercised" name="StockIssuedDuringPeriodSharesUnvestedStockOptionsExercised" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration" />
  <xsd:element id="sibn_StockIssuedDuringPeriodSharesWarrantsExercised" name="StockIssuedDuringPeriodSharesWarrantsExercised" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration" />
  <xsd:element id="sibn_StockIssuedDuringPeriodValueUnvestedStockOptionsExercised" name="StockIssuedDuringPeriodValueUnvestedStockOptionsExercised" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="sibn_StockIssuedDuringPeriodValueWarrantsExercised" name="StockIssuedDuringPeriodValueWarrantsExercised" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="sibn_StockRepurchasedDuringPeriodOriginallyIssuedForExerciseOfUnvestedStockOptionsShares" name="StockRepurchasedDuringPeriodOriginallyIssuedForExerciseOfUnvestedStockOptionsShares" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration" />
  <xsd:element id="sibn_StockRepurchasedDuringPeriodOriginallyIssuedForExerciseOfUnvestedStockOptionsValue" name="StockRepurchasedDuringPeriodOriginallyIssuedForExerciseOfUnvestedStockOptionsValue" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="sibn_TemporaryEquityConversionOfTemporaryEquityToEquityShares" name="TemporaryEquityConversionOfTemporaryEquityToEquityShares" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration" />
  <xsd:element id="sibn_TemporaryEquityConversionOfTemporaryEquityToEquityValue" name="TemporaryEquityConversionOfTemporaryEquityToEquityValue" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="sibn_VestingOfEarlyExercisedStockOptions" name="VestingOfEarlyExercisedStockOptions" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="sibn_WarrantsClassifiedAsEquityAndLiabilitiesPolicyTextBlock" name="WarrantsClassifiedAsEquityAndLiabilitiesPolicyTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="sibn_WarrantsIssuedDecemberTwentySecondTwentySixteenMember" name="WarrantsIssuedDecemberTwentySecondTwentySixteenMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="sibn_WarrantsIssuedJulyTwentySecondTwentyThirteenMember" name="WarrantsIssuedJulyTwentySecondTwentyThirteenMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="sibn_WarrantsIssuedMarchFirstTwentySeventeenMember" name="WarrantsIssuedMarchFirstTwentySeventeenMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="sibn_WarrantsIssuedNovemberNinthTwentyFifteenMember" name="WarrantsIssuedNovemberNinthTwentyFifteenMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="sibn_WarrantsIssuedNovemberTwentySixthTwentyFourteenMember" name="WarrantsIssuedNovemberTwentySixthTwentyFourteenMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="sibn_WarrantsIssuedOctoberTwentiethTwentyFifteenMember" name="WarrantsIssuedOctoberTwentiethTwentyFifteenMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="sibn_WarrantsLiabilityMember" name="WarrantsLiabilityMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="sibn_WarrantsOutstandingFairValueOnDateOfIssuanceOrConversion" name="WarrantsOutstandingFairValueOnDateOfIssuanceOrConversion" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
</xsd:schema>
