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      <link:linkbaseRef xlink:type="simple" xlink:href="cers-20120930_lab.xml" xlink:role="http://www.xbrl.org/2003/role/labelLinkbaseRef" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:title="Label Links, all" />
      <link:linkbaseRef xlink:type="simple" xlink:href="cers-20120930_cal.xml" xlink:role="http://www.xbrl.org/2003/role/calculationLinkbaseRef" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:title="Calculation Links, all" />
      <link:linkbaseRef xlink:type="simple" xlink:href="cers-20120930_def.xml" xlink:role="http://www.xbrl.org/2003/role/definitionLinkbaseRef" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:title="Definition Links, all" />
    </appinfo>
  </annotation>
  <import namespace="http://www.xbrl.org/2003/instance" schemaLocation="http://www.xbrl.org/2003/xbrl-instance-2003-12-31.xsd" />
  <import namespace="http://www.xbrl.org/2003/linkbase" schemaLocation="http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd" />
  <import namespace="http://xbrl.sec.gov/dei/2012-01-31" schemaLocation="http://xbrl.sec.gov/dei/2012/dei-2012-01-31.xsd" />
  <import namespace="http://xbrl.org/2005/xbrldt" schemaLocation="http://www.xbrl.org/2005/xbrldt-2005.xsd" />
  <import namespace="http://fasb.org/us-gaap/2012-01-31" schemaLocation="http://xbrl.fasb.org/us-gaap/2012/elts/us-gaap-2012-01-31.xsd" />
  <import namespace="http://xbrl.sec.gov/exch/2012-01-31" schemaLocation="http://xbrl.sec.gov/exch/2012/exch-2012-01-31.xsd" />
  <import namespace="http://xbrl.sec.gov/country/2012-01-31" schemaLocation="http://xbrl.sec.gov/country/2012/country-2012-01-31.xsd" />
  <import namespace="http://www.xbrl.org/dtr/type/non-numeric" schemaLocation="http://www.xbrl.org/dtr/type/nonNumeric-2009-12-16.xsd" />
  <import namespace="http://www.xbrl.org/dtr/type/numeric" schemaLocation="http://www.xbrl.org/dtr/type/numeric-2009-12-16.xsd" />
  <import namespace="http://fasb.org/us-types/2012-01-31" schemaLocation="http://xbrl.fasb.org/us-gaap/2012/elts/us-types-2012-01-31.xsd" />
  <import namespace="http://xbrl.sec.gov/invest/2012-01-31" schemaLocation="http://xbrl.sec.gov/invest/2012/invest-2012-01-31.xsd" />
  <element id="cers_DocumentAndEntityInformationAbstract" name="DocumentAndEntityInformationAbstract" abstract="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_RevaluationOfWarrantLiability" name="RevaluationOfWarrantLiability" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" />
  <element id="cers_WarrantLiabilityPolicyTextBlock" name="WarrantLiabilityPolicyTextBlock" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_DenominatorAbstract" name="DenominatorAbstract" abstract="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_FairValueOfWarrantsTableTextBlock" name="FairValueOfWarrantsTableTextBlock" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_CustomersThatAccountedForMoreThanTenPercentageOfCompanysProductRevenueTableTextBlock" name="CustomersThatAccountedForMoreThanTenPercentageOfCompanysProductRevenueTableTextBlock" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_CarryingValueMember" name="CarryingValueMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_FairValueMember" name="FairValueMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_FiniteLivedIntangibleAssetsAmortizationExpenseYearSix" name="FiniteLivedIntangibleAssetsAmortizationExpenseYearSix" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" />
  <element id="cers_FiniteLivedIntangibleAssetsAmortizationExpenseYearSeven" name="FiniteLivedIntangibleAssetsAmortizationExpenseYearSeven" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" />
  <element id="cers_FiniteLivedIntangibleAssetsAmortizationExpenseYearEight" name="FiniteLivedIntangibleAssetsAmortizationExpenseYearEight" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" />
  <element id="cers_FiniteLivedIntangibleAssetsAmortizationExpenseYearNine" name="FiniteLivedIntangibleAssetsAmortizationExpenseYearNine" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" />
  <element id="cers_GrowthCapitalLoanMember" name="GrowthCapitalLoanMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_ZeroPointOneOfProductSalesForPlateletSystemMember" name="ZeroPointOneOfProductSalesForPlateletSystemMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_ZeroPointZeroThreeOfProductSalesForPlasmaSystemMember" name="ZeroPointZeroThreeOfProductSalesForPlasmaSystemMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_ZeroPointZeroFiveOfProductSalesForRedBloodCellSystemMember" name="ZeroPointZeroFiveOfProductSalesForRedBloodCellSystemMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_ZeroPointZeroSixFiveOnSaleOfIlluminatorsMember" name="ZeroPointZeroSixFiveOnSaleOfIlluminatorsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_DebtTextualAbstract" name="DebtTextualAbstract" abstract="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_GrowthCapitalFacilityMember" name="GrowthCapitalFacilityMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_ComplianceWithCovenantsMember" name="ComplianceWithCovenantsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_AmountUnderRevolvingLineOfCreditAvailableToCompany" name="AmountUnderRevolvingLineOfCreditAvailableToCompany" type="num:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" />
  <element id="cers_MinimumCashBalance" name="MinimumCashBalance" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" />
  <element id="cers_ClosingCostAndFees" name="ClosingCostAndFees" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" />
  <element id="cers_EtablissementFrancaisDuSangMember" name="EtablissementFrancaisDuSangMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_DelrusIncMember" name="DelrusIncMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_LeaseholdImprovementReflectedInAccruedLiabilities" name="LeaseholdImprovementReflectedInAccruedLiabilities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" />
  <element id="cers_LeaseholdImprovementReflectedInOtherNonCurrentLiabilities" name="LeaseholdImprovementReflectedInOtherNonCurrentLiabilities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" />
  <element id="cers_TwoThousandNineWarrantsMember" name="TwoThousandNineWarrantsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_TwoThousandTenWarrantsMember" name="TwoThousandTenWarrantsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_FairValueOfWarrantsAbstract" name="FairValueOfWarrantsAbstract" abstract="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_SalesAgreementMember" name="SalesAgreementMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_StockholderRightsPlanMember" name="StockholderRightsPlanMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_PreferredStockConversionBasisToCommonShares" name="PreferredStockConversionBasisToCommonShares" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_CommonStockSold" name="CommonStockSold" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_SummaryOfSignificantAccountingPoliciesTextualAbstract" name="SummaryOfSignificantAccountingPoliciesTextualAbstract" abstract="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_StockBasedCompensationTextualAbstract" name="StockBasedCompensationTextualAbstract" abstract="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_StockBasedCompensationAssociatedWithPerformanceBasedStockOptions" name="StockBasedCompensationAssociatedWithPerformanceBasedStockOptions" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" />
  <element id="cers_PerformanceBasedStockOptionsOutstanding" name="PerformanceBasedStockOptionsOutstanding" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" />
  <element id="cers_TwoThousandEightEquityIncentivePlanMember" name="TwoThousandEightEquityIncentivePlanMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_LongTermInvestmentsTextualAbstract" name="LongTermInvestmentsTextualAbstract" abstract="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_GoodwillAndIntangibleAssetsTextualAbstract" name="GoodwillAndIntangibleAssetsTextualAbstract" abstract="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_EligibleToReceiveRoyaltyFee" name="EligibleToReceiveRoyaltyFee" type="num:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_AccruedInventory" name="AccruedInventory" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" />
  <element id="cers_SecuredDebtAbstract" name="SecuredDebtAbstract" abstract="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_MovacoSaMember" name="MovacoSaMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_MlvMember" name="MlvMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_CommitmentsAndContingenciesTextualAbstract" name="CommitmentsAndContingenciesTextualAbstract" abstract="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_StockholdersEquityAdditionalTextualAbstract" name="StockholdersEquityAdditionalTextualAbstract" abstract="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_StockholdersEquityTextualAbstract" name="StockholdersEquityTextualAbstract" abstract="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_CustomersThatAccountedForMoreThanTenPercentageOfCompanyRevenueAbstract" name="CustomersThatAccountedForMoreThanTenPercentageOfCompanyRevenueAbstract" abstract="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_SegmentCustomerAndGeographicInformationTextualAbstract" name="SegmentCustomerAndGeographicInformationTextualAbstract" abstract="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_CapitalLoanMember" name="CapitalLoanMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_WarrantLiabilityMember" name="WarrantLiabilityMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAbstract" name="ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAbstract" abstract="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_QuantificationOfImmaterialPriorPeriodAdjustmentsInPriorInterimFiscalPeriods" name="QuantificationOfImmaterialPriorPeriodAdjustmentsInPriorInterimFiscalPeriods" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" />
  <element id="cers_CumulativeOutstandingTradeReceivablesNumberOfMajorCustomers" name="CumulativeOutstandingTradeReceivablesNumberOfMajorCustomers" type="xbrli:integerItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" />
  <element id="cers_CumulativeOutstandingTradeReceivablesMajorCustomersPercentage" name="CumulativeOutstandingTradeReceivablesMajorCustomersPercentage" type="num:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" />
  <element id="cers_DebtInstrumentUnamortizedCurrent" name="DebtInstrumentUnamortizedCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" />
  <element id="cers_DebtInstrumentUnamortizedNoncurrent" name="DebtInstrumentUnamortizedNoncurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" />
  <element id="cers_DebtInstrumentCarryingCurrent" name="DebtInstrumentCarryingCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" />
  <element id="cers_DebtInstrumentCarryingNonCurrent" name="DebtInstrumentCarryingNonCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" />
  <element id="cers_MinimumTermOfNonCancelableOperatingLeases" name="MinimumTermOfNonCancelableOperatingLeases" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_ExpirationOfNonCancelableOperatingLeasesMaximumYear" name="ExpirationOfNonCancelableOperatingLeasesMaximumYear" type="xbrli:gYearItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_EarlyTerminationOfNonCancelableOperatingLeasesMinimumPeriod" name="EarlyTerminationOfNonCancelableOperatingLeasesMinimumPeriod" type="xbrli:gYearMonthItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_ProceedsFromLandlordFinancingLeaseholdImprovement" name="ProceedsFromLandlordFinancingLeaseholdImprovement" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" />
  <element id="cers_OutstandingLiabilityRelatedToLeaseholdImprovementsCurrentAndNonCurrent" name="OutstandingLiabilityRelatedToLeaseholdImprovementsCurrentAndNonCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" />
  <element id="cers_MaximumAmountAvailableUnderOffering" name="MaximumAmountAvailableUnderOffering" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" />
  <element id="cers_DesignatedPreferredStockForFutureIssuance" name="DesignatedPreferredStockForFutureIssuance" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" />
  <element id="cers_GovernmentGrantsAndCooperativeAgreementsMember" name="GovernmentGrantsAndCooperativeAgreementsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_OwnershipPercentageUnderCostMethodInvestments" name="OwnershipPercentageUnderCostMethodInvestments" type="num:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_LongTermInvestmentsAdditionalTextualAbstract" name="LongTermInvestmentsAdditionalTextualAbstract" abstract="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_WarrantsExercised" name="WarrantsExercised" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" />
  <element id="cers_AvailableForSaleSecuritiesDisclosureTextBlock" name="AvailableForSaleSecuritiesDisclosureTextBlock" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_AvailableForSaleSecuritiesByContractualMaturityDueInOneYear" name="AvailableForSaleSecuritiesByContractualMaturityDueInOneYear" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" />
  <element id="cers_AvailableForSaleSecuritiesByContractualMaturityDueGreaterThanThreeYearsAndLessThanFiveYears" name="AvailableForSaleSecuritiesByContractualMaturityDueGreaterThanThreeYearsAndLessThanFiveYears" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" />
  <element id="cers_AvailableForSaleSecuritiesByContractualMaturity" name="AvailableForSaleSecuritiesByContractualMaturity" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" />
  <element id="cers_AvailableForSaleSecuritiesTextualAbstract" name="AvailableForSaleSecuritiesTextualAbstract" abstract="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_DerecognitionOfTaxPositions" name="DerecognitionOfTaxPositions" type="num:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_LineOfCreditFacilityWithdrawals" name="LineOfCreditFacilityWithdrawals" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" />
  <element id="cers_FinalPaymentFeePercentage" name="FinalPaymentFeePercentage" type="num:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" />
  <element id="cers_MinimumRevenuesLevelsPercentage" name="MinimumRevenuesLevelsPercentage" type="num:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_ConcordLeaseMember" name="ConcordLeaseMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_MinimumPercentageOfCommonStockAcquiredByStockholders" name="MinimumPercentageOfCommonStockAcquiredByStockholders" type="num:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_AumLtdMember" name="AumLtdMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_RoyaltyRateAppliedTowardsSaleOfProducts" name="RoyaltyRateAppliedTowardsSaleOfProducts" type="num:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_MaximumNumberOfSharesOfCommonStockAuthorizedForIssuance" name="MaximumNumberOfSharesOfCommonStockAuthorizedForIssuance" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" />
  <element id="cers_EmployeeStockPurchasePlanMember" name="EmployeeStockPurchasePlanMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_NumberOfSharesAvailableForFutureIssuance" name="NumberOfSharesAvailableForFutureIssuance" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" />
  <element id="cers_IncreaseInSharesOfCommonStockAuthorizedForIssuance" name="IncreaseInSharesOfCommonStockAuthorizedForIssuance" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" />
  <element id="cers_OptionsAndOtherStockBasedAwards" name="OptionsAndOtherStockBasedAwards" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" />
  <element id="cers_ExercisablePeriod" name="ExercisablePeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_ConversionOfPreferredStockToCommonStockDate" name="ConversionOfPreferredStockToCommonStockDate" type="xbrli:dateItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_PercentageOfProceedsPayableAsCompensationToUnderwriter" name="PercentageOfProceedsPayableAsCompensationToUnderwriter" type="num:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_TwoThousandTenUnitOfferingMember" name="TwoThousandTenUnitOfferingMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_TwoThousandNineUnitOfferingMember" name="TwoThousandNineUnitOfferingMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_NumeratorAbstract" name="NumeratorAbstract" abstract="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_PercentageOfInvestmentsMadeInSubsidiary" name="PercentageOfInvestmentsMadeInSubsidiary" type="num:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" />
  <element id="cers_CantorMember" name="CantorMember" abstract="true" type="nonnum:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_LicenseAgreementTableTextBlock" name="LicenseAgreementTableTextBlock" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_LicenseAgreementsAbstract" name="LicenseAgreementsAbstract" abstract="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_CommitmentsAndContingenciesAdditionalTextualAbstract" name="CommitmentsAndContingenciesAdditionalTextualAbstract" abstract="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_ManufacturingAndSupplyAgreementsMember" name="ManufacturingAndSupplyAgreementsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_LicenseAgreementTextualAbstract" name="LicenseAgreementTextualAbstract" abstract="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_LicenseAgreementAdditionalTextualAbstract" name="LicenseAgreementAdditionalTextualAbstract" abstract="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_PaymentForRoyalty" name="PaymentForRoyalty" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" />
  <element id="cers_PaymentForManufacturingOfEntityProducts" name="PaymentForManufacturingOfEntityProducts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" />
  <element id="cers_AvailableForSaleSecuritiesByContractualMaturityAbstract" name="AvailableForSaleSecuritiesByContractualMaturityAbstract" abstract="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_ProductWarrantyReceivableCurrent" name="ProductWarrantyReceivableCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" />
  <element id="cers_LineOfCreditFacilityAnnualCommitmentFeeAmount" name="LineOfCreditFacilityAnnualCommitmentFeeAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" />
  <element id="cers_LineOfCreditFacilityInterestPaymentPeriod" name="LineOfCreditFacilityInterestPaymentPeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_LineOfCreditFacilityPrincipalAndInterestRepaymentAdditionalPeriod" name="LineOfCreditFacilityPrincipalAndInterestRepaymentAdditionalPeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_InventoryLifeFinishedGoodsPeriod" name="InventoryLifeFinishedGoodsPeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_InventoryLifeWorkInProcessPeriod" name="InventoryLifeWorkInProcessPeriod" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_SafetyProductWarrantyPeriod" name="SafetyProductWarrantyPeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" />
  <element id="cers_ProductWarrantyClaimsSettled" name="ProductWarrantyClaimsSettled" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" />
  <element id="cers_InventoryWriteDownAgainstWhichOffsettingWarrantyClaimAvailable" name="InventoryWriteDownAgainstWhichOffsettingWarrantyClaimAvailable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" />
</schema>
