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  <xsd:element abstract="true" id="capn_NonQualifiedStockOptionsMember" name="NonQualifiedStockOptionsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="capn_NoncashTransactionExerciseofWarrants" name="NoncashTransactionExerciseofWarrants" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="capn_OwnershipInterestPercentageofVotingRightsofStock" name="OwnershipInterestPercentageofVotingRightsofStock" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="capn_PlacementAgentWarrantsMember" name="PlacementAgentWarrantsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="capn_PrivatePlacementSeriesBWarrantsMember" name="PrivatePlacementSeriesBWarrantsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="capn_ReductionInInitialPublicOfferingCostsPayable" name="ReductionInInitialPublicOfferingCostsPayable" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="capn_RedwoodCityCaliforniaMember" name="RedwoodCityCaliforniaMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="capn_RoyaltyPaymentPeriod" name="RoyaltyPaymentPeriod" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="capn_SabbyManagementLlcMember" name="SabbyManagementLlcMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="capn_SabbyPurchaseAgreementFirstClosingMember" name="SabbyPurchaseAgreementFirstClosingMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="capn_SabbyPurchaseAgreementSecondClosingMember" name="SabbyPurchaseAgreementSecondClosingMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="capn_SaleofStockConversionofConvertibleStockConversionPricePerShare" name="SaleofStockConversionofConvertibleStockConversionPricePerShare" nillable="true" substitutionGroup="xbrli:item" type="num:perShareItemType" xbrli:periodType="instant" />
  <xsd:element id="capn_ScheduleofFullyDilutiveSecuritiesExcludedfromComputationofEarningsPerShareTableTextBlock" name="ScheduleofFullyDilutiveSecuritiesExcludedfromComputationofEarningsPerShareTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="capn_SecurityPurchaseAgreementNumberofClosings" name="SecurityPurchaseAgreementNumberofClosings" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="capn_SeriesAWarrantsMember" name="SeriesAWarrantsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="capn_SeriesAWarrantsToPurchaseCommonStockMember" name="SeriesAWarrantsToPurchaseCommonStockMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="capn_SeriesBWarrantToPurchaseCommonStockMember" name="SeriesBWarrantToPurchaseCommonStockMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="capn_SeriesBWarrantsMember" name="SeriesBWarrantsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="capn_SeriesCWarrantToPurchaseCommonStockMember" name="SeriesCWarrantToPurchaseCommonStockMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="capn_SeriesCWarrantsMember" name="SeriesCWarrantsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="capn_SeriesDWarrantToPurchaseCommonStockMember" name="SeriesDWarrantToPurchaseCommonStockMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="capn_SeriesDWarrantsMember" name="SeriesDWarrantsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="capn_StockIssuedDuringPeriodSharesCashlessExerciseOfWarrants" name="StockIssuedDuringPeriodSharesCashlessExerciseOfWarrants" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration" />
  <xsd:element id="capn_StockIssuedDuringPeriodSharesExercisedOfWarrants" name="StockIssuedDuringPeriodSharesExercisedOfWarrants" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="capn_SubleaseofExcessSpaceMember" name="SubleaseofExcessSpaceMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="capn_TemporaryEquityStatedValuePerShare" name="TemporaryEquityStatedValuePerShare" nillable="true" substitutionGroup="xbrli:item" type="num:perShareItemType" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="capn_TenderOfferSeriesBWarrantsMember" name="TenderOfferSeriesBWarrantsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="capn_TransactionCostsIncludedinAccruedLiabilities" name="TransactionCostsIncludedinAccruedLiabilities" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="capn_TwentySixteenSabbyPurchaseAgreementMember" name="TwentySixteenSabbyPurchaseAgreementMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="capn_TwoThousandAndTenAndTwoThousandAndTwelveConvertiblePromissoryNotesMember" name="TwoThousandAndTenAndTwoThousandAndTwelveConvertiblePromissoryNotesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="capn_UnderwriterMember" name="UnderwriterMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="capn_WarrantLiabilityDisclosureTextBlock" name="WarrantLiabilityDisclosureTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="capn_WarrantsExercised" name="WarrantsExercised" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="capn_WarrantsToPurchaseCommonStockMember" name="WarrantsToPurchaseCommonStockMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="capn_WorkingCapital" name="WorkingCapital" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
</xsd:schema>