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<!-- Created: Wed Apr 08 17:49:26 UTC 2026 -->
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  <roleRef xlink:type="simple" xlink:href="https://xbrl.sec.gov/ecd/2025/ecd-2025.xsd#PvpAdjustmentsOnly" roleURI="http://xbrl.sec.gov/ecd/role/PvpAdjustmentsOnly"/>
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  <arcroleRef xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#domain-member" arcroleURI="http://xbrl.org/int/dim/arcrole/domain-member"/>
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    <loc xlink:type="locator" xlink:label="shc_EquityAwardsAdjustmentsMember" xlink:href="shc-20251231.xsd#shc_EquityAwardsAdjustmentsMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ecd_AllAdjToCompMember" xlink:to="shc_EquityAwardsAdjustmentsMember" order="5" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="shc_FairValueOfStockAndOptionAwardsForfeitedDuringTheCoveredYearMember" xlink:href="shc-20251231.xsd#shc_FairValueOfStockAndOptionAwardsForfeitedDuringTheCoveredYearMember"/>
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