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  <xsd:element abstract="true" id="xbit_statement-statement-note-6-net-loss-per-share-potentially-dilutive-securities-outstanding-details" name="statement-statement-note-6-net-loss-per-share-potentially-dilutive-securities-outstanding-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="xbit_statement-statement-note-6-net-loss-per-share-tables" name="statement-statement-note-6-net-loss-per-share-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="xbit_statement-statement-significant-accounting-policies-policies" name="statement-statement-significant-accounting-policies-policies" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
</xsd:schema>
