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  <xs:element id="lnth_PaymentsForAssetAcquisitions" abstract="false" name="PaymentsForAssetAcquisitions" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="lnth_PerspectiveTherapeuticsIncFullyDilutedBasisMember" abstract="true" name="PerspectiveTherapeuticsIncFullyDilutedBasisMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="lnth_AssetAcquisitionsNumberOfAssetsAcquired" abstract="false" name="AssetAcquisitionsNumberOfAssetsAcquired" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="lnth_AssetsAndLiabilitiesLesseeTableTextBlock" abstract="false" name="AssetsAndLiabilitiesLesseeTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:textBlockItemType"/>
  <xs:element id="lnth_BusinessCombinationIncreaseDecreaseInAcquiredIntangibleAssets" abstract="false" name="BusinessCombinationIncreaseDecreaseInAcquiredIntangibleAssets" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="lnth_ProceedsFromSaleOfRoyaltyRights" abstract="false" name="ProceedsFromSaleOfRoyaltyRights" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="lnth_CollaborationPaymentsMember" abstract="true" name="CollaborationPaymentsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="lnth_OtherPrecisionDiagnosticsMember" abstract="true" name="OtherPrecisionDiagnosticsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="lnth_JamesThrallMember" abstract="true" name="JamesThrallMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="lnth_BedfordMassachusettsMember" abstract="true" name="BedfordMassachusettsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="lnth_MeasurementInputProbabilityOfSuccessMember" abstract="true" name="MeasurementInputProbabilityOfSuccessMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="lnth_BusinessAcquisitionSharesAcquired" abstract="false" name="BusinessAcquisitionSharesAcquired" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="lnth_LineOfCreditFacilityAccordionFeatureHigherBorrowingCapacityOption" abstract="false" name="LineOfCreditFacilityAccordionFeatureHigherBorrowingCapacityOption" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="lnth_TotalPrecisionDiagnosticsMember" abstract="true" name="TotalPrecisionDiagnosticsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="lnth_OtherNonoperatingIncomeExpenseMiscellaneous" abstract="false" name="OtherNonoperatingIncomeExpenseMiscellaneous" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="lnth_DisposalGroupIncludingDiscontinuedOperationRightOfUseLiability" abstract="false" name="DisposalGroupIncludingDiscontinuedOperationRightOfUseLiability" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="lnth_BusinessCombinationConsiderationTransferredEquityInterestsIssuedAndIssuableShares" abstract="false" name="BusinessCombinationConsiderationTransferredEquityInterestsIssuedAndIssuableShares" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
</xs:schema>
