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  <xs:element id="ck0001824293_SeriesECommonWarrantMember" abstract="true" name="SeriesECommonWarrantMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ck0001824293_April2025PAWarrantsMember" abstract="true" name="April2025PAWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ck0001824293_SeriesFCommonStockWarrantsMember" abstract="true" name="SeriesFCommonStockWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ck0001824293_December2025PAWarrantsMember" abstract="true" name="December2025PAWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ck0001824293_SaleOfStockWeightedAveragePricePerShare" abstract="false" name="SaleOfStockWeightedAveragePricePerShare" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType"/>
  <xs:element id="ck0001824293_SaleOfStockNumberOfSecuritiesIssuedPerTransaction" abstract="false" name="SaleOfStockNumberOfSecuritiesIssuedPerTransaction" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="ck0001824293_SaleOfStockAggregateCashFeePercentageOfGrossProceeds" abstract="false" name="SaleOfStockAggregateCashFeePercentageOfGrossProceeds" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="ck0001824293_SaleOfStockManagementFeePercentageOfGrossProceeds" abstract="false" name="SaleOfStockManagementFeePercentageOfGrossProceeds" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="ck0001824293_SaleOfStockReimbursementOfAccountableExpenses" abstract="false" name="SaleOfStockReimbursementOfAccountableExpenses" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ck0001824293_SaleOfStockLegalFeesAndExpensesAndOtherOutOfPocketExpenses" abstract="false" name="SaleOfStockLegalFeesAndExpensesAndOtherOutOfPocketExpenses" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ck0001824293_SaleOfStockClearingExpenses" abstract="false" name="SaleOfStockClearingExpenses" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="ck0001824293_SeriesECommonWarrantsAndApril2025PAWarrantsMember" abstract="true" name="SeriesECommonWarrantsAndApril2025PAWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ck0001824293_WarrantsExpiringInOctober2026Member" abstract="true" name="WarrantsExpiringInOctober2026Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ck0001824293_WarrantsExpiringInMay2027Member" abstract="true" name="WarrantsExpiringInMay2027Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ck0001824293_WarrantsExpiringInJuly2027Member" abstract="true" name="WarrantsExpiringInJuly2027Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ck0001824293_WarrantsExpiringInApril2028Member" abstract="true" name="WarrantsExpiringInApril2028Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ck0001824293_WarrantsExpiringInFebruary2029Member" abstract="true" name="WarrantsExpiringInFebruary2029Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ck0001824293_WarrantsExpiringInJune2029Member" abstract="true" name="WarrantsExpiringInJune2029Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ck0001824293_WarrantsExpiringInSeptember2029Member" abstract="true" name="WarrantsExpiringInSeptember2029Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ck0001824293_WarrantsExpiringInOctober2029OneMember" abstract="true" name="WarrantsExpiringInOctober2029OneMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ck0001824293_WarrantsExpiringInOctober2029TwoMember" abstract="true" name="WarrantsExpiringInOctober2029TwoMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ck0001824293_WarrantsExpiringInApril2030OneMember" abstract="true" name="WarrantsExpiringInApril2030OneMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ck0001824293_WarrantsExpiringInApril2030TwoMember" abstract="true" name="WarrantsExpiringInApril2030TwoMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ck0001824293_WarrantsExpiringInDecember2030OneMember" abstract="true" name="WarrantsExpiringInDecember2030OneMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ck0001824293_WarrantsExpiringInDecember2030TwoMember" abstract="true" name="WarrantsExpiringInDecember2030TwoMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ck0001824293_AmendedAndRestated2018EquityIncentivePlanMember" abstract="true" name="AmendedAndRestated2018EquityIncentivePlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="ck0001824293_ShareBasedCompensationArrangementByShareBasedPaymentAwardIncreaseInSharesReservedForIssuanceAsPercentageOfAggregateCommonStockOutstandingMaximum" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardIncreaseInSharesReservedForIssuanceAsPercentageOfAggregateCommonStockOutstandingMaximum" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
</xs:schema>
