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          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_cik0001276533_CallRiskMember" xml:lang="en-US">Call Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_cik0001276533_CallRiskMember" xlink:to="lab_cik0001276533_CallRiskMember" />
          <link:loc xlink:type="locator" xlink:href="cik0001276533-20260731.xsd#cik0001276533_CollateralizedDebtObligationcdoRiskAndCollateralizedLoanObligationcloRiskMember" xlink:label="loc_cik0001276533_CollateralizedDebtObligationcdoRiskAndCollateralizedLoanObligationcloRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_cik0001276533_CollateralizedDebtObligationcdoRiskAndCollateralizedLoanObligationcloRiskMember" xml:lang="en-US">Collateralized Debt Obligation (CDO) Risk and Collateralized Loan Obligation (CLO) Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_cik0001276533_CollateralizedDebtObligationcdoRiskAndCollateralizedLoanObligationcloRiskMember" xlink:to="lab_cik0001276533_CollateralizedDebtObligationcdoRiskAndCollateralizedLoanObligationcloRiskMember" />
          <link:loc xlink:type="locator" xlink:href="cik0001276533-20260731.xsd#cik0001276533_CreditsRisksMember" xlink:label="loc_cik0001276533_CreditsRisksMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_cik0001276533_CreditsRisksMember" xml:lang="en-US">Credits Risks [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_cik0001276533_CreditsRisksMember" xlink:to="lab_cik0001276533_CreditsRisksMember" />
          <link:loc xlink:type="locator" xlink:href="cik0001276533-20260731.xsd#cik0001276533_CreditSpreadRiskMember" xlink:label="loc_cik0001276533_CreditSpreadRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_cik0001276533_CreditSpreadRiskMember" xml:lang="en-US">Credit Spread Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_cik0001276533_CreditSpreadRiskMember" xlink:to="lab_cik0001276533_CreditSpreadRiskMember" />
          <link:loc xlink:type="locator" xlink:href="cik0001276533-20260731.xsd#cik0001276533_DebtSecuritiesRiskMember" xlink:label="loc_cik0001276533_DebtSecuritiesRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_cik0001276533_DebtSecuritiesRiskMember" xml:lang="en-US">Debt Securities Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_cik0001276533_DebtSecuritiesRiskMember" xlink:to="lab_cik0001276533_DebtSecuritiesRiskMember" />
          <link:loc xlink:type="locator" xlink:href="cik0001276533-20260731.xsd#cik0001276533_DebtorInPossessionDipFinancingRiskMember" xlink:label="loc_cik0001276533_DebtorInPossessionDipFinancingRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_cik0001276533_DebtorInPossessionDipFinancingRiskMember" xml:lang="en-US">Debtor In Possession (DIP) Financing Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_cik0001276533_DebtorInPossessionDipFinancingRiskMember" xlink:to="lab_cik0001276533_DebtorInPossessionDipFinancingRiskMember" />
          <link:loc xlink:type="locator" xlink:href="cik0001276533-20260731.xsd#cik0001276533_DeflationRiskMember" xlink:label="loc_cik0001276533_DeflationRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_cik0001276533_DeflationRiskMember" xml:lang="en-US">Deflation Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_cik0001276533_DeflationRiskMember" xlink:to="lab_cik0001276533_DeflationRiskMember" />
          <link:loc xlink:type="locator" xlink:href="cik0001276533-20260731.xsd#cik0001276533_DepositaryReceiptsRiskMember" xlink:label="loc_cik0001276533_DepositaryReceiptsRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_cik0001276533_DepositaryReceiptsRiskMember" xml:lang="en-US">Depositary Receipts Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_cik0001276533_DepositaryReceiptsRiskMember" xlink:to="lab_cik0001276533_DepositaryReceiptsRiskMember" />
          <link:loc xlink:type="locator" xlink:href="cik0001276533-20260731.xsd#cik0001276533_DerivativesRiskMember" xlink:label="loc_cik0001276533_DerivativesRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_cik0001276533_DerivativesRiskMember" xml:lang="en-US">Derivatives Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_cik0001276533_DerivativesRiskMember" xlink:to="lab_cik0001276533_DerivativesRiskMember" />
          <link:loc xlink:type="locator" xlink:href="cik0001276533-20260731.xsd#cik0001276533_DurationRiskMember" xlink:label="loc_cik0001276533_DurationRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_cik0001276533_DurationRiskMember" xml:lang="en-US">Duration Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_cik0001276533_DurationRiskMember" xlink:to="lab_cik0001276533_DurationRiskMember" />
          <link:loc xlink:type="locator" xlink:href="cik0001276533-20260731.xsd#cik0001276533_EquitySecuritiesRiskMember" xlink:label="loc_cik0001276533_EquitySecuritiesRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_cik0001276533_EquitySecuritiesRiskMember" xml:lang="en-US">Equity Securities Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_cik0001276533_EquitySecuritiesRiskMember" xlink:to="lab_cik0001276533_EquitySecuritiesRiskMember" />
          <link:loc xlink:type="locator" xlink:href="cik0001276533-20260731.xsd#cik0001276533_FinancialFuturesAndOptionsTransactionsRiskMember" xlink:label="loc_cik0001276533_FinancialFuturesAndOptionsTransactionsRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_cik0001276533_FinancialFuturesAndOptionsTransactionsRiskMember" xml:lang="en-US">Financial Futures and Options Transactions Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_cik0001276533_FinancialFuturesAndOptionsTransactionsRiskMember" xlink:to="lab_cik0001276533_FinancialFuturesAndOptionsTransactionsRiskMember" />
          <link:loc xlink:type="locator" xlink:href="cik0001276533-20260731.xsd#cik0001276533_FloatingRateAndFixedToFloatingRateSecuritiesRiskMember" xlink:label="loc_cik0001276533_FloatingRateAndFixedToFloatingRateSecuritiesRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_cik0001276533_FloatingRateAndFixedToFloatingRateSecuritiesRiskMember" xml:lang="en-US">Floating Rate and Fixed to Floating Rate Securities Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_cik0001276533_FloatingRateAndFixedToFloatingRateSecuritiesRiskMember" xlink:to="lab_cik0001276533_FloatingRateAndFixedToFloatingRateSecuritiesRiskMember" />
          <link:loc xlink:type="locator" xlink:href="cik0001276533-20260731.xsd#cik0001276533_ForeignCurrencyRiskMember" xlink:label="loc_cik0001276533_ForeignCurrencyRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_cik0001276533_ForeignCurrencyRiskMember" xml:lang="en-US">Foreign Currency Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_cik0001276533_ForeignCurrencyRiskMember" xlink:to="lab_cik0001276533_ForeignCurrencyRiskMember" />
          <link:loc xlink:type="locator" xlink:href="cik0001276533-20260731.xsd#cik0001276533_ForeignemergingMarketsIssuerRiskMember" xlink:label="loc_cik0001276533_ForeignemergingMarketsIssuerRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_cik0001276533_ForeignemergingMarketsIssuerRiskMember" xml:lang="en-US">Foreign/Emerging Markets Issuer Risk</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_cik0001276533_ForeignemergingMarketsIssuerRiskMember" xlink:to="lab_cik0001276533_ForeignemergingMarketsIssuerRiskMember" />
          <link:loc xlink:type="locator" xlink:href="cik0001276533-20260731.xsd#cik0001276533_HedgingRiskMember" xlink:label="loc_cik0001276533_HedgingRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_cik0001276533_HedgingRiskMember" xml:lang="en-US">Hedging Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_cik0001276533_HedgingRiskMember" xlink:to="lab_cik0001276533_HedgingRiskMember" />
          <link:loc xlink:type="locator" xlink:href="cik0001276533-20260731.xsd#cik0001276533_IncomeRiskMember" xlink:label="loc_cik0001276533_IncomeRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_cik0001276533_IncomeRiskMember" xml:lang="en-US">Income Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_cik0001276533_IncomeRiskMember" xlink:to="lab_cik0001276533_IncomeRiskMember" />
          <link:loc xlink:type="locator" xlink:href="cik0001276533-20260731.xsd#cik0001276533_InflationRiskMember" xlink:label="loc_cik0001276533_InflationRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_cik0001276533_InflationRiskMember" xml:lang="en-US">Inflation Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_cik0001276533_InflationRiskMember" xlink:to="lab_cik0001276533_InflationRiskMember" />
          <link:loc xlink:type="locator" xlink:href="cik0001276533-20260731.xsd#cik0001276533_InflationCorrelationRiskMember" xlink:label="loc_cik0001276533_InflationCorrelationRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_cik0001276533_InflationCorrelationRiskMember" xml:lang="en-US">Inflation Correlation Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_cik0001276533_InflationCorrelationRiskMember" xlink:to="lab_cik0001276533_InflationCorrelationRiskMember" />
          <link:loc xlink:type="locator" xlink:href="cik0001276533-20260731.xsd#cik0001276533_InverseFloatingRateSecuritiesRiskMember" xlink:label="loc_cik0001276533_InverseFloatingRateSecuritiesRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_cik0001276533_InverseFloatingRateSecuritiesRiskMember" xml:lang="en-US">Inverse Floating Rate Securities Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_cik0001276533_InverseFloatingRateSecuritiesRiskMember" xlink:to="lab_cik0001276533_InverseFloatingRateSecuritiesRiskMember" />
          <link:loc xlink:type="locator" xlink:href="cik0001276533-20260731.xsd#cik0001276533_LoanParticipationRiskMember" xlink:label="loc_cik0001276533_LoanParticipationRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_cik0001276533_LoanParticipationRiskMember" xml:lang="en-US">Loan Participation Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_cik0001276533_LoanParticipationRiskMember" xlink:to="lab_cik0001276533_LoanParticipationRiskMember" />
          <link:loc xlink:type="locator" xlink:href="cik0001276533-20260731.xsd#cik0001276533_LoanRiskMember" xlink:label="loc_cik0001276533_LoanRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_cik0001276533_LoanRiskMember" xml:lang="en-US">Loan Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_cik0001276533_LoanRiskMember" xlink:to="lab_cik0001276533_LoanRiskMember" />
          <link:loc xlink:type="locator" xlink:href="cik0001276533-20260731.xsd#cik0001276533_MortgageBackedSecuritiesMbsAndAssetBackedSecuritiesAbsRiskMember" xlink:label="loc_cik0001276533_MortgageBackedSecuritiesMbsAndAssetBackedSecuritiesAbsRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_cik0001276533_MortgageBackedSecuritiesMbsAndAssetBackedSecuritiesAbsRiskMember" xml:lang="en-US">Mortgage-Backed Securities ("MBS") and Asset-Backed Securities ("ABS") Risk</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_cik0001276533_MortgageBackedSecuritiesMbsAndAssetBackedSecuritiesAbsRiskMember" xlink:to="lab_cik0001276533_MortgageBackedSecuritiesMbsAndAssetBackedSecuritiesAbsRiskMember" />
          <link:loc xlink:type="locator" xlink:href="cik0001276533-20260731.xsd#cik0001276533_OtherInvestmentCompaniesRiskMember" xlink:label="loc_cik0001276533_OtherInvestmentCompaniesRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_cik0001276533_OtherInvestmentCompaniesRiskMember" xml:lang="en-US">Other Investment Companies Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_cik0001276533_OtherInvestmentCompaniesRiskMember" xlink:to="lab_cik0001276533_OtherInvestmentCompaniesRiskMember" />
          <link:loc xlink:type="locator" xlink:href="cik0001276533-20260731.xsd#cik0001276533_ReinvestmentRiskMember" xlink:label="loc_cik0001276533_ReinvestmentRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_cik0001276533_ReinvestmentRiskMember" xml:lang="en-US">Reinvestment Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_cik0001276533_ReinvestmentRiskMember" xlink:to="lab_cik0001276533_ReinvestmentRiskMember" />
          <link:loc xlink:type="locator" xlink:href="cik0001276533-20260731.xsd#cik0001276533_RestrictedAndIlliquidInvestmentsRiskMember" xlink:label="loc_cik0001276533_RestrictedAndIlliquidInvestmentsRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_cik0001276533_RestrictedAndIlliquidInvestmentsRiskMember" xml:lang="en-US">Restricted and Illiquid Investments Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_cik0001276533_RestrictedAndIlliquidInvestmentsRiskMember" xlink:to="lab_cik0001276533_RestrictedAndIlliquidInvestmentsRiskMember" />
          <link:loc xlink:type="locator" xlink:href="cik0001276533-20260731.xsd#cik0001276533_SecondLienLoansAndUnsecuredLoansRiskMember" xlink:label="loc_cik0001276533_SecondLienLoansAndUnsecuredLoansRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_cik0001276533_SecondLienLoansAndUnsecuredLoansRiskMember" xml:lang="en-US">Second Lien Loans and Unsecured Loans Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_cik0001276533_SecondLienLoansAndUnsecuredLoansRiskMember" xlink:to="lab_cik0001276533_SecondLienLoansAndUnsecuredLoansRiskMember" />
          <link:loc xlink:type="locator" xlink:href="cik0001276533-20260731.xsd#cik0001276533_SeniorLoanAgentRiskMember" xlink:label="loc_cik0001276533_SeniorLoanAgentRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_cik0001276533_SeniorLoanAgentRiskMember" xml:lang="en-US">Senior Loan Agent Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_cik0001276533_SeniorLoanAgentRiskMember" xlink:to="lab_cik0001276533_SeniorLoanAgentRiskMember" />
          <link:loc xlink:type="locator" xlink:href="cik0001276533-20260731.xsd#cik0001276533_SeniorLoanRiskMember" xlink:label="loc_cik0001276533_SeniorLoanRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_cik0001276533_SeniorLoanRiskMember" xml:lang="en-US">Senior Loan Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_cik0001276533_SeniorLoanRiskMember" xlink:to="lab_cik0001276533_SeniorLoanRiskMember" />
          <link:loc xlink:type="locator" xlink:href="cik0001276533-20260731.xsd#cik0001276533_StructuredProductsRiskMember" xlink:label="loc_cik0001276533_StructuredProductsRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_cik0001276533_StructuredProductsRiskMember" xml:lang="en-US">Structured Products Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_cik0001276533_StructuredProductsRiskMember" xlink:to="lab_cik0001276533_StructuredProductsRiskMember" />
          <link:loc xlink:type="locator" xlink:href="cik0001276533-20260731.xsd#cik0001276533_SovereignGovernmentAndSupranationalDebtRiskMember" xlink:label="loc_cik0001276533_SovereignGovernmentAndSupranationalDebtRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_cik0001276533_SovereignGovernmentAndSupranationalDebtRiskMember" xml:lang="en-US">Sovereign Government and Supranational Debt Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_cik0001276533_SovereignGovernmentAndSupranationalDebtRiskMember" xlink:to="lab_cik0001276533_SovereignGovernmentAndSupranationalDebtRiskMember" />
          <link:loc xlink:type="locator" xlink:href="cik0001276533-20260731.xsd#cik0001276533_SubordinatedLoansAndOtherSubordinatedDebtInstrumentsRiskMember" xlink:label="loc_cik0001276533_SubordinatedLoansAndOtherSubordinatedDebtInstrumentsRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_cik0001276533_SubordinatedLoansAndOtherSubordinatedDebtInstrumentsRiskMember" xml:lang="en-US">Subordinated Loans and Other Subordinated Debt Instruments Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_cik0001276533_SubordinatedLoansAndOtherSubordinatedDebtInstrumentsRiskMember" xlink:to="lab_cik0001276533_SubordinatedLoansAndOtherSubordinatedDebtInstrumentsRiskMember" />
          <link:loc xlink:type="locator" xlink:href="cik0001276533-20260731.xsd#cik0001276533_SwapTransactionsRiskMember" xlink:label="loc_cik0001276533_SwapTransactionsRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_cik0001276533_SwapTransactionsRiskMember" xml:lang="en-US">Swap Transactions Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_cik0001276533_SwapTransactionsRiskMember" xlink:to="lab_cik0001276533_SwapTransactionsRiskMember" />
          <link:loc xlink:type="locator" xlink:href="cik0001276533-20260731.xsd#cik0001276533_UnratedSecuritiesRiskMember" xlink:label="loc_cik0001276533_UnratedSecuritiesRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_cik0001276533_UnratedSecuritiesRiskMember" xml:lang="en-US">Unrated Securities Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_cik0001276533_UnratedSecuritiesRiskMember" xlink:to="lab_cik0001276533_UnratedSecuritiesRiskMember" />
          <link:loc xlink:type="locator" xlink:href="cik0001276533-20260731.xsd#cik0001276533_UsGovernmentSecuritiesRiskMember" xlink:label="loc_cik0001276533_UsGovernmentSecuritiesRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_cik0001276533_UsGovernmentSecuritiesRiskMember" xml:lang="en-US">U.S. Government Securities Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_cik0001276533_UsGovernmentSecuritiesRiskMember" xlink:to="lab_cik0001276533_UsGovernmentSecuritiesRiskMember" />
          <link:loc xlink:type="locator" xlink:href="cik0001276533-20260731.xsd#cik0001276533_ValuationRiskMember" xlink:label="loc_cik0001276533_ValuationRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_cik0001276533_ValuationRiskMember" xml:lang="en-US">Valuation Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_cik0001276533_ValuationRiskMember" xlink:to="lab_cik0001276533_ValuationRiskMember" />
          <link:loc xlink:type="locator" xlink:href="cik0001276533-20260731.xsd#cik0001276533_WarrantsAndEquitySecuritiesRiskMember" xlink:label="loc_cik0001276533_WarrantsAndEquitySecuritiesRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_cik0001276533_WarrantsAndEquitySecuritiesRiskMember" xml:lang="en-US">Warrants and Equity Securities Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_cik0001276533_WarrantsAndEquitySecuritiesRiskMember" xlink:to="lab_cik0001276533_WarrantsAndEquitySecuritiesRiskMember" />
          <link:loc xlink:type="locator" xlink:href="cik0001276533-20260731.xsd#cik0001276533_WhenissuedAndDelayeddeliveryTransactionsRiskMember" xlink:label="loc_cik0001276533_WhenissuedAndDelayeddeliveryTransactionsRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_cik0001276533_WhenissuedAndDelayeddeliveryTransactionsRiskMember" xml:lang="en-US">WhenIssued and DelayedDelivery Transactions Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_cik0001276533_WhenissuedAndDelayeddeliveryTransactionsRiskMember" xlink:to="lab_cik0001276533_WhenissuedAndDelayeddeliveryTransactionsRiskMember" />
          <link:loc xlink:type="locator" xlink:href="cik0001276533-20260731.xsd#cik0001276533_ZeroCouponBondsOrPayinkindSecuritiesRiskMember" xlink:label="loc_cik0001276533_ZeroCouponBondsOrPayinkindSecuritiesRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_cik0001276533_ZeroCouponBondsOrPayinkindSecuritiesRiskMember" xml:lang="en-US">Zero Coupon Bonds or PayInKind Securities Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_cik0001276533_ZeroCouponBondsOrPayinkindSecuritiesRiskMember" xlink:to="lab_cik0001276533_ZeroCouponBondsOrPayinkindSecuritiesRiskMember" />
          <link:loc xlink:type="locator" xlink:href="cik0001276533-20260731.xsd#cik0001276533_AntiTakeoverProvisionsMember" xlink:label="loc_cik0001276533_AntiTakeoverProvisionsMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_cik0001276533_AntiTakeoverProvisionsMember" xml:lang="en-US">Anti Takeover Provisions [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_cik0001276533_AntiTakeoverProvisionsMember" xlink:to="lab_cik0001276533_AntiTakeoverProvisionsMember" />
          <link:loc xlink:type="locator" xlink:href="cik0001276533-20260731.xsd#cik0001276533_BorrowingRiskMember" xlink:label="loc_cik0001276533_BorrowingRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_cik0001276533_BorrowingRiskMember" xml:lang="en-US">Borrowing Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_cik0001276533_BorrowingRiskMember" xlink:to="lab_cik0001276533_BorrowingRiskMember" />
          <link:loc xlink:type="locator" xlink:href="cik0001276533-20260731.xsd#cik0001276533_CounterpartyRiskMember" xlink:label="loc_cik0001276533_CounterpartyRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_cik0001276533_CounterpartyRiskMember" xml:lang="en-US">Counterparty Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_cik0001276533_CounterpartyRiskMember" xlink:to="lab_cik0001276533_CounterpartyRiskMember" />
          <link:loc xlink:type="locator" xlink:href="cik0001276533-20260731.xsd#cik0001276533_CybersecurityRiskMember" xlink:label="loc_cik0001276533_CybersecurityRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_cik0001276533_CybersecurityRiskMember" xml:lang="en-US">Cybersecurity Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_cik0001276533_CybersecurityRiskMember" xlink:to="lab_cik0001276533_CybersecurityRiskMember" />
          <link:loc xlink:type="locator" xlink:href="cik0001276533-20260731.xsd#cik0001276533_FundTaxRiskMember" xlink:label="loc_cik0001276533_FundTaxRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_cik0001276533_FundTaxRiskMember" xml:lang="en-US">Fund Tax Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_cik0001276533_FundTaxRiskMember" xlink:to="lab_cik0001276533_FundTaxRiskMember" />
          <link:loc xlink:type="locator" xlink:href="cik0001276533-20260731.xsd#cik0001276533_GlobalEconomicRiskMember" xlink:label="loc_cik0001276533_GlobalEconomicRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_cik0001276533_GlobalEconomicRiskMember" xml:lang="en-US">Global Economic Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_cik0001276533_GlobalEconomicRiskMember" xlink:to="lab_cik0001276533_GlobalEconomicRiskMember" />
          <link:loc xlink:type="locator" xlink:href="cik0001276533-20260731.xsd#cik0001276533_InvestmentAndMarketRiskMember" xlink:label="loc_cik0001276533_InvestmentAndMarketRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_cik0001276533_InvestmentAndMarketRiskMember" xml:lang="en-US">Investment and Market Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_cik0001276533_InvestmentAndMarketRiskMember" xlink:to="lab_cik0001276533_InvestmentAndMarketRiskMember" />
          <link:loc xlink:type="locator" xlink:href="cik0001276533-20260731.xsd#cik0001276533_LegislationAndRegulatoryRiskMember" xlink:label="loc_cik0001276533_LegislationAndRegulatoryRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_cik0001276533_LegislationAndRegulatoryRiskMember" xml:lang="en-US">Legislation and Regulatory Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_cik0001276533_LegislationAndRegulatoryRiskMember" xlink:to="lab_cik0001276533_LegislationAndRegulatoryRiskMember" />
          <link:loc xlink:type="locator" xlink:href="cik0001276533-20260731.xsd#cik0001276533_LeverageRiskMember" xlink:label="loc_cik0001276533_LeverageRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_cik0001276533_LeverageRiskMember" xml:lang="en-US">Leverage Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_cik0001276533_LeverageRiskMember" xlink:to="lab_cik0001276533_LeverageRiskMember" />
          <link:loc xlink:type="locator" xlink:href="cik0001276533-20260731.xsd#cik0001276533_MarketDiscountFromNetAssetValueMember" xlink:label="loc_cik0001276533_MarketDiscountFromNetAssetValueMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_cik0001276533_MarketDiscountFromNetAssetValueMember" xml:lang="en-US">Market Discount from Net Asset Value [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_cik0001276533_MarketDiscountFromNetAssetValueMember" xlink:to="lab_cik0001276533_MarketDiscountFromNetAssetValueMember" />
          <link:loc xlink:type="locator" xlink:href="cik0001276533-20260731.xsd#cik0001276533_RecentMarketConditionsMember" xlink:label="loc_cik0001276533_RecentMarketConditionsMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_cik0001276533_RecentMarketConditionsMember" xml:lang="en-US">Recent Market Conditions [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_cik0001276533_RecentMarketConditionsMember" xlink:to="lab_cik0001276533_RecentMarketConditionsMember" />
          <link:loc xlink:type="locator" xlink:href="cik0001276533-20260731.xsd#cik0001276533_ReverseRepurchaseAgreementRiskMember" xlink:label="loc_cik0001276533_ReverseRepurchaseAgreementRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_cik0001276533_ReverseRepurchaseAgreementRiskMember" xml:lang="en-US">Reverse Repurchase Agreement Risk [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_cik0001276533_ReverseRepurchaseAgreementRiskMember" xlink:to="lab_cik0001276533_ReverseRepurchaseAgreementRiskMember" />
        </link:labelLink>
      </link:linkbase>
    </appinfo>
  </annotation>
  <import namespace="http://xbrl.sec.gov/cef/2026" schemaLocation="https://xbrl.sec.gov/cef/2026/cef-2026.xsd" />
  <import namespace="http://xbrl.sec.gov/cef-pre/2026" schemaLocation="https://xbrl.sec.gov/cef/2026/cef-2026_pre.xsd" />
  <import namespace="http://www.xbrl.org/2003/instance" schemaLocation="http://www.xbrl.org/2003/xbrl-instance-2003-12-31.xsd" />
  <import namespace="http://xbrl.org/2005/xbrldt" schemaLocation="http://www.xbrl.org/2005/xbrldt-2005.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/dei/2026" schemaLocation="https://xbrl.sec.gov/dei/2026/dei-2026.xsd" />
  <import namespace="http://www.xbrl.org/2003/linkbase" schemaLocation="http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd" />
  <import namespace="http://www.xbrl.org/dtr/type/2020-01-21" schemaLocation="https://www.xbrl.org/dtr/type/2020-01-21/types.xsd" />
  <element name="CommonSharesMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001276533_CommonSharesMember" substitutionGroup="xbrli:item" />
  <element name="BorrowingsOutstandingMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001276533_BorrowingsOutstandingMember" substitutionGroup="xbrli:item" />
  <element name="TaxableFundPreferredTfpSharesMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001276533_TaxableFundPreferredTfpSharesMember" substitutionGroup="xbrli:item" />
  <element name="TermPreferredSharesMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001276533_TermPreferredSharesMember" substitutionGroup="xbrli:item" />
  <element name="BasisRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001276533_BasisRiskMember" substitutionGroup="xbrli:item" />
  <element name="BelowInvestmentGradeRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001276533_BelowInvestmentGradeRiskMember" substitutionGroup="xbrli:item" />
  <element name="CallRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001276533_CallRiskMember" substitutionGroup="xbrli:item" />
  <element name="CreditSpreadRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001276533_CreditSpreadRiskMember" substitutionGroup="xbrli:item" />
  <element name="DebtSecuritiesRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001276533_DebtSecuritiesRiskMember" substitutionGroup="xbrli:item" />
  <element name="DebtorInPossessionDipFinancingRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001276533_DebtorInPossessionDipFinancingRiskMember" substitutionGroup="xbrli:item" />
  <element name="DeflationRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001276533_DeflationRiskMember" substitutionGroup="xbrli:item" />
  <element name="DepositaryReceiptsRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001276533_DepositaryReceiptsRiskMember" substitutionGroup="xbrli:item" />
  <element name="DerivativesRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001276533_DerivativesRiskMember" substitutionGroup="xbrli:item" />
  <element name="DurationRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001276533_DurationRiskMember" substitutionGroup="xbrli:item" />
  <element name="EquitySecuritiesRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001276533_EquitySecuritiesRiskMember" substitutionGroup="xbrli:item" />
  <element name="FinancialFuturesAndOptionsTransactionsRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001276533_FinancialFuturesAndOptionsTransactionsRiskMember" substitutionGroup="xbrli:item" />
  <element name="FloatingRateAndFixedToFloatingRateSecuritiesRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001276533_FloatingRateAndFixedToFloatingRateSecuritiesRiskMember" substitutionGroup="xbrli:item" />
  <element name="ForeignCurrencyRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001276533_ForeignCurrencyRiskMember" substitutionGroup="xbrli:item" />
  <element name="HedgingRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001276533_HedgingRiskMember" substitutionGroup="xbrli:item" />
  <element name="IncomeRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001276533_IncomeRiskMember" substitutionGroup="xbrli:item" />
  <element name="InflationRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001276533_InflationRiskMember" substitutionGroup="xbrli:item" />
  <element name="InflationCorrelationRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001276533_InflationCorrelationRiskMember" substitutionGroup="xbrli:item" />
  <element name="LoanParticipationRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001276533_LoanParticipationRiskMember" substitutionGroup="xbrli:item" />
  <element name="LoanRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001276533_LoanRiskMember" substitutionGroup="xbrli:item" />
  <element name="OtherInvestmentCompaniesRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001276533_OtherInvestmentCompaniesRiskMember" substitutionGroup="xbrli:item" />
  <element name="ReinvestmentRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001276533_ReinvestmentRiskMember" substitutionGroup="xbrli:item" />
  <element name="RestrictedAndIlliquidInvestmentsRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001276533_RestrictedAndIlliquidInvestmentsRiskMember" substitutionGroup="xbrli:item" />
  <element name="SecondLienLoansAndUnsecuredLoansRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001276533_SecondLienLoansAndUnsecuredLoansRiskMember" substitutionGroup="xbrli:item" />
  <element name="SeniorLoanAgentRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001276533_SeniorLoanAgentRiskMember" substitutionGroup="xbrli:item" />
  <element name="SeniorLoanRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001276533_SeniorLoanRiskMember" substitutionGroup="xbrli:item" />
  <element name="StructuredProductsRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001276533_StructuredProductsRiskMember" substitutionGroup="xbrli:item" />
  <element name="SovereignGovernmentAndSupranationalDebtRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001276533_SovereignGovernmentAndSupranationalDebtRiskMember" substitutionGroup="xbrli:item" />
  <element name="SubordinatedLoansAndOtherSubordinatedDebtInstrumentsRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001276533_SubordinatedLoansAndOtherSubordinatedDebtInstrumentsRiskMember" substitutionGroup="xbrli:item" />
  <element name="SwapTransactionsRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001276533_SwapTransactionsRiskMember" substitutionGroup="xbrli:item" />
  <element name="UnratedSecuritiesRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001276533_UnratedSecuritiesRiskMember" substitutionGroup="xbrli:item" />
  <element name="UsGovernmentSecuritiesRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001276533_UsGovernmentSecuritiesRiskMember" substitutionGroup="xbrli:item" />
  <element name="ValuationRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001276533_ValuationRiskMember" substitutionGroup="xbrli:item" />
  <element name="WarrantsAndEquitySecuritiesRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001276533_WarrantsAndEquitySecuritiesRiskMember" substitutionGroup="xbrli:item" />
  <element name="WhenissuedAndDelayeddeliveryTransactionsRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001276533_WhenissuedAndDelayeddeliveryTransactionsRiskMember" substitutionGroup="xbrli:item" />
  <element name="ZeroCouponBondsOrPayinkindSecuritiesRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001276533_ZeroCouponBondsOrPayinkindSecuritiesRiskMember" substitutionGroup="xbrli:item" />
  <element name="AntiTakeoverProvisionsMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001276533_AntiTakeoverProvisionsMember" substitutionGroup="xbrli:item" />
  <element name="BorrowingRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001276533_BorrowingRiskMember" substitutionGroup="xbrli:item" />
  <element name="CounterpartyRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001276533_CounterpartyRiskMember" substitutionGroup="xbrli:item" />
  <element name="CybersecurityRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001276533_CybersecurityRiskMember" substitutionGroup="xbrli:item" />
  <element name="FundTaxRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001276533_FundTaxRiskMember" substitutionGroup="xbrli:item" />
  <element name="GlobalEconomicRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001276533_GlobalEconomicRiskMember" substitutionGroup="xbrli:item" />
  <element name="InvestmentAndMarketRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001276533_InvestmentAndMarketRiskMember" substitutionGroup="xbrli:item" />
  <element name="LegislationAndRegulatoryRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001276533_LegislationAndRegulatoryRiskMember" substitutionGroup="xbrli:item" />
  <element name="LeverageRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001276533_LeverageRiskMember" substitutionGroup="xbrli:item" />
  <element name="MarketDiscountFromNetAssetValueMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001276533_MarketDiscountFromNetAssetValueMember" substitutionGroup="xbrli:item" />
  <element name="RecentMarketConditionsMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001276533_RecentMarketConditionsMember" substitutionGroup="xbrli:item" />
  <element name="ReverseRepurchaseAgreementRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001276533_ReverseRepurchaseAgreementRiskMember" substitutionGroup="xbrli:item" />
  <element name="CollateralizedDebtObligationcdoRiskAndCollateralizedLoanObligationcloRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001276533_CollateralizedDebtObligationcdoRiskAndCollateralizedLoanObligationcloRiskMember" substitutionGroup="xbrli:item" />
  <element name="ForeignemergingMarketsIssuerRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001276533_ForeignemergingMarketsIssuerRiskMember" substitutionGroup="xbrli:item" />
  <element name="InverseFloatingRateSecuritiesRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001276533_InverseFloatingRateSecuritiesRiskMember" substitutionGroup="xbrli:item" />
  <element name="MortgageBackedSecuritiesMbsAndAssetBackedSecuritiesAbsRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001276533_MortgageBackedSecuritiesMbsAndAssetBackedSecuritiesAbsRiskMember" substitutionGroup="xbrli:item" />
  <element name="CreditsRisksMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="cik0001276533_CreditsRisksMember" substitutionGroup="xbrli:item" />
</schema>
