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          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_cik0001493683_PreferredSharesMember" xml:lang="en-US">Preferred Shares [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_cik0001493683_PreferredSharesMember" xlink:to="lab_cik0001493683_PreferredSharesMember" />
        </link:labelLink>
      </link:linkbase>
    </appinfo>
  </annotation>
  <import namespace="http://www.xbrl.org/2003/instance" schemaLocation="http://www.xbrl.org/2003/xbrl-instance-2003-12-31.xsd" />
  <import namespace="http://www.xbrl.org/2003/linkbase" schemaLocation="http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd" />
  <import namespace="http://xbrl.org/2005/xbrldt" schemaLocation="http://www.xbrl.org/2005/xbrldt-2005.xsd" />
  <import namespace="http://xbrl.sec.gov/dei/2025" schemaLocation="https://xbrl.sec.gov/dei/2025/dei-2025.xsd" />
  <import namespace="http://www.xbrl.org/dtr/type/2024-01-31" schemaLocation="https://www.xbrl.org/dtr/type/2024-01-31/types.xsd" />
  <import namespace="http://xbrl.sec.gov/cef/2025" schemaLocation="https://xbrl.sec.gov/cef/2025/cef-2025.xsd" />
  <import namespace="http://xbrl.sec.gov/cef-pre/2025" schemaLocation="https://xbrl.sec.gov/cef/2025/cef-2025_pre.xsd" />
  <element name="CommonSharesMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001493683_CommonSharesMember" substitutionGroup="xbrli:item" />
  <element name="RiskAssociatedWithRecentMarketEventsMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001493683_RiskAssociatedWithRecentMarketEventsMember" substitutionGroup="xbrli:item" />
  <element name="RelianceOnTheAdvisorRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001493683_RelianceOnTheAdvisorRiskMember" substitutionGroup="xbrli:item" />
  <element name="RelianceOnServiceProvidersRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001493683_RelianceOnServiceProvidersRiskMember" substitutionGroup="xbrli:item" />
  <element name="RegulationAsACommodityPoolMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001493683_RegulationAsACommodityPoolMember" substitutionGroup="xbrli:item" />
  <element name="RegulationAndGovernmentInterventionRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001493683_RegulationAndGovernmentInterventionRiskMember" substitutionGroup="xbrli:item" />
  <element name="ReferenceRateReplacementRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001493683_ReferenceRateReplacementRiskMember" substitutionGroup="xbrli:item" />
  <element name="PotentialConflictsOfInterestOfTheAdvisorAndOthersMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001493683_PotentialConflictsOfInterestOfTheAdvisorAndOthersMember" substitutionGroup="xbrli:item" />
  <element name="PortfolioTurnoverRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001493683_PortfolioTurnoverRiskMember" substitutionGroup="xbrli:item" />
  <element name="OperationalAndTechnologyRisksMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001493683_OperationalAndTechnologyRisksMember" substitutionGroup="xbrli:item" />
  <element name="MisconductOfEmployeesAndOfServiceProvidersRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001493683_MisconductOfEmployeesAndOfServiceProvidersRiskMember" substitutionGroup="xbrli:item" />
  <element name="MarketDisruptionAndGeopoliticalRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001493683_MarketDisruptionAndGeopoliticalRiskMember" substitutionGroup="xbrli:item" />
  <element name="ManagementRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001493683_ManagementRiskMember" substitutionGroup="xbrli:item" />
  <element name="LegalTaxAndRegulatoryRisksMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001493683_LegalTaxAndRegulatoryRisksMember" substitutionGroup="xbrli:item" />
  <element name="InformationTechnologySystemsRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001493683_InformationTechnologySystemsRiskMember" substitutionGroup="xbrli:item" />
  <element name="AntiTakeoverProvisionsRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001493683_AntiTakeoverProvisionsRiskMember" substitutionGroup="xbrli:item" />
  <element name="GeneralRisksMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001493683_GeneralRisksMember" substitutionGroup="xbrli:item" />
  <element name="FailuresOfFuturesCommissionMerchantsAndClearingOrganizationsRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001493683_FailuresOfFuturesCommissionMerchantsAndClearingOrganizationsRiskMember" substitutionGroup="xbrli:item" />
  <element name="DefensiveInvestingRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001493683_DefensiveInvestingRiskMember" substitutionGroup="xbrli:item" />
  <element name="DecisionMakingAuthorityRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001493683_DecisionMakingAuthorityRiskMember" substitutionGroup="xbrli:item" />
  <element name="ValuationRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001493683_ValuationRiskMember" substitutionGroup="xbrli:item" />
  <element name="PreferredSharesMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001493683_PreferredSharesMember" substitutionGroup="xbrli:item" />
</schema>
