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  <xs:element id="sibn_DeferredTaxAssetsOperatingLeaseLiabilities" abstract="false" name="DeferredTaxAssetsOperatingLeaseLiabilities" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="sibn_DeferredTaxAssetsCapitalizedResearchAndDevelopment" abstract="false" name="DeferredTaxAssetsCapitalizedResearchAndDevelopment" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="sibn_IncomeTaxesValuationAllowanceRollForward" abstract="true" name="IncomeTaxesValuationAllowanceRollForward" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="sibn_UnrecognizedTaxBenefitsIncreaseDecreaseResultingFromPriorPeriodTaxPositions" abstract="false" name="UnrecognizedTaxBenefitsIncreaseDecreaseResultingFromPriorPeriodTaxPositions" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="sibn_RelatedPartyTransactionTermOfAgreement" abstract="false" name="RelatedPartyTransactionTermOfAgreement" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="sibn_LauraFrancisMember" abstract="true" name="LauraFrancisMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="sibn_AnshulMaheshwariMember" abstract="true" name="AnshulMaheshwariMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="sibn_LauraFrancisTradingArrangementCommonStockMember" abstract="true" name="LauraFrancisTradingArrangementCommonStockMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="sibn_LauraFrancisTradingArrangementRestrictedStockUnitsMember" abstract="true" name="LauraFrancisTradingArrangementRestrictedStockUnitsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="sibn_LauraFrancisTradingArrangementPerformanceBasedRestrictedStockUnitsMember" abstract="true" name="LauraFrancisTradingArrangementPerformanceBasedRestrictedStockUnitsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="sibn_AnshulMaheshwariTradingArrangementCommonStockMember" abstract="true" name="AnshulMaheshwariTradingArrangementCommonStockMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="sibn_AnshulMaheshwariTradingArrangementRestrictedStockUnitsMember" abstract="true" name="AnshulMaheshwariTradingArrangementRestrictedStockUnitsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="sibn_AnshulMaheshwariTradingArrangementPerformanceBasedRestrictedStockUnitsMember" abstract="true" name="AnshulMaheshwariTradingArrangementPerformanceBasedRestrictedStockUnitsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
</xs:schema>
