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  <xs:element id="prm_RelatedPartyTransactionVariableAnnualAdvisoryAmountSharesFactorValue" abstract="false" name="RelatedPartyTransactionVariableAnnualAdvisoryAmountSharesFactorValue" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="prm_RelatedPartyTransactionAnnualAdvisoryAmountPercentageInShares" abstract="false" name="RelatedPartyTransactionAnnualAdvisoryAmountPercentageInShares" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="prm_RelatedPartyTransactionAnnualAdvisoryAmountShares" abstract="false" name="RelatedPartyTransactionAnnualAdvisoryAmountShares" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="prm_RelatedPartyTransactionAnnualAdvisoryAmountPercentageInCash" abstract="false" name="RelatedPartyTransactionAnnualAdvisoryAmountPercentageInCash" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="prm_PaymentsForRelatedPartyTransaction" abstract="false" name="PaymentsForRelatedPartyTransaction" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="prm_RelatedPartyTransactionAnnualAdvisoryAmountSharesIssued" abstract="false" name="RelatedPartyTransactionAnnualAdvisoryAmountSharesIssued" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="prm_ServiceAndOtherMember" abstract="true" name="ServiceAndOtherMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="prm_CostOfGoodsAndServicesSoldAdjusted" abstract="false" name="CostOfGoodsAndServicesSoldAdjusted" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="prm_SellingGeneralAndAdministrativeExpenseAdjusted" abstract="false" name="SellingGeneralAndAdministrativeExpenseAdjusted" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="prm_AdjustedEarningsBeforeInterestTaxesDepreciationAndAmortization" abstract="false" name="AdjustedEarningsBeforeInterestTaxesDepreciationAndAmortization" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="prm_NonRecurringExpenses" abstract="false" name="NonRecurringExpenses" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="prm_PurchaseAccountingAdjustments" abstract="false" name="PurchaseAccountingAdjustments" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="prm_SegmentAssets" abstract="false" name="SegmentAssets" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="prm_TaxAssets" abstract="false" name="TaxAssets" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="prm_NonUSExcludingCanadaMember" abstract="true" name="NonUSExcludingCanadaMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="prm_OtherForeignJurisdictionsMember" abstract="true" name="OtherForeignJurisdictionsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
</xs:schema>
