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    <element id="PTN_UnrecognizedCompensationCost" name="UnrecognizedCompensationCost" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="PTN_StockIssuedDuringPeriodValueRestrictedStockUnitshares" name="StockIssuedDuringPeriodValueRestrictedStockUnitshares" nillable="true" xbrli:periodType="duration" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" />
    <element id="PTN_WithholdingTaxesRelatedToRestrictedStockUnitsAmoun" name="WithholdingTaxesRelatedToRestrictedStockUnitsAmoun" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="PTN_DeferredTaxAssetsIrcSection" name="DeferredTaxAssetsIrcSection" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="PTN_DeferredTaxAssetsBasisDifferencesInFixedAssetsAndOther" name="DeferredTaxAssetsBasisDifferencesInFixedAssetsAndOther" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="PTN_AllowanceForLoanAndLeaseLossLoansAcquired" name="AllowanceForLoanAndLeaseLossLoansAcquired" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
</schema>
