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    <element id="SSSS_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisExercisesAndConversions" name="FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisExercisesAndConversions" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="SSSS_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainAndLoss" name="FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainAndLoss" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="SSSS_FairValueAssetRecurringBasisStillHeldUnrealizedGainAndLossOci" name="FairValueAssetRecurringBasisStillHeldUnrealizedGainAndLossOci" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="SSSS_ConvertibleNotePercentage" name="ConvertibleNotePercentage" nillable="true" xbrli:periodType="instant" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" />
    <element id="SSSS_NumberOfPositions" name="NumberOfPositions" nillable="true" xbrli:periodType="instant" type="xbrli:integerItemType" substitutionGroup="xbrli:item" />
    <element id="SSSS_NumberOfPortfolioCompanies" name="NumberOfPortfolioCompanies" nillable="true" xbrli:periodType="instant" type="xbrli:integerItemType" substitutionGroup="xbrli:item" />
    <element id="SSSS_StockRepurchasePercentage" name="StockRepurchasePercentage" nillable="true" xbrli:periodType="instant" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" />
    <element id="SSSS_PercentageOfSalesPrice" name="PercentageOfSalesPrice" nillable="true" xbrli:periodType="duration" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" />
    <element id="SSSS_IncomeLossFromContinuingOperationsDiluted" name="IncomeLossFromContinuingOperationsDiluted" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="SSSS_InvestmentCompanyUnrealizedInvestmentIncomeLossFromOperationsPerShare" name="InvestmentCompanyUnrealizedInvestmentIncomeLossFromOperationsPerShare" nillable="true" xbrli:periodType="duration" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" />
    <element id="SSSS_InvestmentCompanyIssuanceOfferingPerShare" name="InvestmentCompanyIssuanceOfferingPerShare" nillable="true" xbrli:periodType="duration" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" />
    <element id="SSSS_InvestmentCompanyRepurchasePerShare" name="InvestmentCompanyRepurchasePerShare" nillable="true" xbrli:periodType="duration" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" />
    <element id="SSSS_InvestmentCompanyShareBasedCompensationArrangementByShareBasedPayment" name="InvestmentCompanyShareBasedCompensationArrangementByShareBasedPayment" nillable="true" xbrli:periodType="duration" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" />
    <element id="SSSS_MarketValueValuePerShare" name="MarketValueValuePerShare" nillable="true" xbrli:periodType="instant" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" />
    <element id="SSSS_InvestmentCompanyTotalReturnBasedonMarketValue" name="InvestmentCompanyTotalReturnBasedonMarketValue" nillable="true" xbrli:periodType="duration" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" />
    <element id="SSSS_AverageNetAsset" name="AverageNetAsset" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="SSSS_InvestmentCompanyTurnoverRatioAfterIncentiveAllocation" name="InvestmentCompanyTurnoverRatioAfterIncentiveAllocation" nillable="true" xbrli:periodType="duration" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" />
    <element id="SSSS_ClosingMarketPricePerNote" name="ClosingMarketPricePerNote" nillable="true" xbrli:periodType="instant" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" />
    <element id="SSSS_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedAndExercisableWeightedAverageGrantDateFairValue" name="SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedAndExercisableWeightedAverageGrantDateFairValue" nillable="true" xbrli:periodType="instant" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" />
    <element id="SSSS_ShareBasedCompensationArrangementByShareBasedPaymentAwardOtherThanOptionsVestedAndExpectedToVestOutstandingNumber" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOtherThanOptionsVestedAndExpectedToVestOutstandingNumber" nillable="true" xbrli:periodType="instant" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" />
    <element id="SSSS_StockOwnershipPercentage" name="StockOwnershipPercentage" nillable="true" xbrli:periodType="duration" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" />
    <element id="SSSS_UnrecognizedShareBasedCompensation" name="UnrecognizedShareBasedCompensation" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="SSSS_StockIssuedDuringPeriodSharesRestrictedStockAwardValue" name="StockIssuedDuringPeriodSharesRestrictedStockAwardValue" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="SSSS_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodValue" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodValue" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="SSSS_NumberOfSharesQuantity" name="NumberOfSharesQuantity" nillable="true" xbrli:periodType="duration" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" />
</schema>
