<?xml version="1.0" encoding="utf-8" standalone="yes"?>
<!-- Compliance Xpressware Instance Document http://www.compliancexpressware.com/  -->
<!-- Version: 1.0.0 --><!-- Creation date:14:03:59 GMT-0700 -->
<!-- Copyright (c) Compliance Xpressware, LLP. All Rights Reserved. -->
<link:linkbase xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd" xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xlink="http://www.w3.org/1999/xlink">
  <link:roleRef roleURI="http://www.ltbridge.com/taxonomy/role/BalanceSheet" xlink:type="simple" xlink:href="ltbr-20141231.xsd#role_BalanceSheet"/>
  <link:calculationLink xlink:type="extended" xlink:role="http://www.ltbridge.com/taxonomy/role/BalanceSheet">
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValue" xlink:label="CashAndCashEquivalentsAtCarryingValue" xlink:title="CashAndCashEquivalentsAtCarryingValue"/>
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_AssetsCurrent" xlink:label="AssetsCurrent" xlink:title="AssetsCurrent"/>
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="AssetsCurrent" xlink:to="CashAndCashEquivalentsAtCarryingValue" use="optional" order="3" weight="1"/>
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_MarketableSecuritiesCurrent" xlink:label="MarketableSecuritiesCurrent" xlink:title="MarketableSecuritiesCurrent"/>
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="AssetsCurrent" xlink:to="MarketableSecuritiesCurrent" use="optional" order="4" weight="1"/>
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_RestrictedCashAndCashEquivalents" xlink:label="RestrictedCashAndCashEquivalents" xlink:title="RestrictedCashAndCashEquivalents"/>
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="AssetsCurrent" xlink:to="RestrictedCashAndCashEquivalents" use="optional" order="5" weight="1"/>
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_AccountsReceivableNetCurrent" xlink:label="AccountsReceivableNetCurrent" xlink:title="AccountsReceivableNetCurrent"/>
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="AssetsCurrent" xlink:to="AccountsReceivableNetCurrent" use="optional" order="6" weight="1"/>
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_PrepaidExpenseCurrent" xlink:label="PrepaidExpenseCurrent" xlink:title="PrepaidExpenseCurrent"/>
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="AssetsCurrent" xlink:to="PrepaidExpenseCurrent" use="optional" order="7" weight="1"/>
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_Assets" xlink:label="Assets" xlink:title="Assets"/>
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="Assets" xlink:to="AssetsCurrent" use="optional" order="8" weight="1"/>
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_PropertyPlantAndEquipmentNet" xlink:label="PropertyPlantAndEquipmentNet" xlink:title="PropertyPlantAndEquipmentNet"/>
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="Assets" xlink:to="PropertyPlantAndEquipmentNet" use="optional" order="9" weight="1"/>
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill" xlink:label="IndefiniteLivedIntangibleAssetsExcludingGoodwill" xlink:title="IndefiniteLivedIntangibleAssetsExcludingGoodwill"/>
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="Assets" xlink:to="IndefiniteLivedIntangibleAssetsExcludingGoodwill" use="optional" order="11" weight="1"/>
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_AccountsPayableAndAccruedLiabilitiesCurrent" xlink:label="AccountsPayableAndAccruedLiabilitiesCurrent" xlink:title="AccountsPayableAndAccruedLiabilitiesCurrent"/>
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_Liabilities" xlink:label="Liabilities" xlink:title="Liabilities"/>
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="Liabilities" xlink:to="AccountsPayableAndAccruedLiabilitiesCurrent" use="optional" order="15" weight="1"/>
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_LiabilitiesAndStockholdersEquity" xlink:label="LiabilitiesAndStockholdersEquity" xlink:title="LiabilitiesAndStockholdersEquity"/>
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="LiabilitiesAndStockholdersEquity" xlink:to="Liabilities" use="optional" order="16" weight="1"/>
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_PreferredStockValue" xlink:label="PreferredStockValue" xlink:title="PreferredStockValue"/>
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_StockholdersEquity" xlink:label="StockholdersEquity" xlink:title="StockholdersEquity"/>
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="StockholdersEquity" xlink:to="PreferredStockValue" use="optional" order="19" weight="1"/>
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_CommonStockValue" xlink:label="CommonStockValue" xlink:title="CommonStockValue"/>
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="StockholdersEquity" xlink:to="CommonStockValue" use="optional" order="20" weight="1"/>
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_AdditionalPaidInCapital" xlink:label="AdditionalPaidInCapital" xlink:title="AdditionalPaidInCapital"/>
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="StockholdersEquity" xlink:to="AdditionalPaidInCapital" use="optional" order="21" weight="1"/>
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_RetainedEarningsAccumulatedDeficit" xlink:label="RetainedEarningsAccumulatedDeficit" xlink:title="RetainedEarningsAccumulatedDeficit"/>
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="StockholdersEquity" xlink:to="RetainedEarningsAccumulatedDeficit" use="optional" order="22" weight="1"/>
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_CommonStockSharesSubscriptions" xlink:label="CommonStockSharesSubscriptions" xlink:title="CommonStockSharesSubscriptions"/>
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="StockholdersEquity" xlink:to="CommonStockSharesSubscriptions" use="optional" order="23" weight="1"/>
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="LiabilitiesAndStockholdersEquity" xlink:to="StockholdersEquity" use="optional" order="24" weight="1"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.ltbridge.com/taxonomy/role/BalanceSheetParenthetical" xlink:type="simple" xlink:href="ltbr-20141231.xsd#role_BalanceSheetParenthetical"/>
  <link:calculationLink xlink:type="extended" xlink:role="http://www.ltbridge.com/taxonomy/role/BalanceSheetParenthetical"/>
  <link:roleRef roleURI="http://www.ltbridge.com/taxonomy/role/IncomeStatement" xlink:type="simple" xlink:href="ltbr-20141231.xsd#role_IncomeStatement"/>
  <link:calculationLink xlink:type="extended" xlink:role="http://www.ltbridge.com/taxonomy/role/IncomeStatement">
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_Revenues" xlink:label="Revenues" xlink:title="Revenues"/>
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_GrossProfit" xlink:label="GrossProfit" xlink:title="GrossProfit"/>
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="GrossProfit" xlink:to="Revenues" use="optional" order="2" weight="1"/>
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_CostOfRevenue" xlink:label="CostOfRevenue" xlink:title="CostOfRevenue"/>
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="GrossProfit" xlink:to="CostOfRevenue" use="optional" order="3" weight="-1"/>
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_OperatingIncomeLoss" xlink:label="OperatingIncomeLoss" xlink:title="OperatingIncomeLoss"/>
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="OperatingIncomeLoss" xlink:to="GrossProfit" use="optional" order="4" weight="1"/>
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_GeneralAndAdministrativeExpense" xlink:label="GeneralAndAdministrativeExpense" xlink:title="GeneralAndAdministrativeExpense"/>
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_OperatingExpenses" xlink:label="OperatingExpenses" xlink:title="OperatingExpenses"/>
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="OperatingExpenses" xlink:to="GeneralAndAdministrativeExpense" use="optional" order="6" weight="1"/>
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ResearchAndDevelopmentExpense" xlink:label="ResearchAndDevelopmentExpense" xlink:title="ResearchAndDevelopmentExpense"/>
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="OperatingExpenses" xlink:to="ResearchAndDevelopmentExpense" use="optional" order="7" weight="1"/>
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="OperatingIncomeLoss" xlink:to="OperatingExpenses" use="optional" order="8" weight="-1"/>
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments" xlink:label="IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments" xlink:title="IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments"/>
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments" xlink:to="OperatingIncomeLoss" use="optional" order="9" weight="1"/>
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_InterestIncomeExpenseNet" xlink:label="InterestIncomeExpenseNet" xlink:title="InterestIncomeExpenseNet"/>
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_NonoperatingIncomeExpense" xlink:label="NonoperatingIncomeExpense" xlink:title="NonoperatingIncomeExpense"/>
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="NonoperatingIncomeExpense" xlink:to="InterestIncomeExpenseNet" use="optional" order="11" weight="1"/>
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_OtherNonoperatingIncomeExpense" xlink:label="OtherNonoperatingIncomeExpense" xlink:title="OtherNonoperatingIncomeExpense"/>
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="NonoperatingIncomeExpense" xlink:to="OtherNonoperatingIncomeExpense" use="optional" order="12" weight="1"/>
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments" xlink:to="NonoperatingIncomeExpense" use="optional" order="13" weight="1"/>
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_NetIncomeLoss" xlink:label="NetIncomeLoss" xlink:title="NetIncomeLoss"/>
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="NetIncomeLoss" xlink:to="IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments" use="optional" order="14" weight="1"/>
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_IncomeTaxExpenseBenefit" xlink:label="IncomeTaxExpenseBenefit" xlink:title="IncomeTaxExpenseBenefit"/>
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="NetIncomeLoss" xlink:to="IncomeTaxExpenseBenefit" use="optional" order="15" weight="-1"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.ltbridge.com/taxonomy/role/CashFlows" xlink:type="simple" xlink:href="ltbr-20141231.xsd#role_CashFlows"/>
  <link:calculationLink xlink:type="extended" xlink:role="http://www.ltbridge.com/taxonomy/role/CashFlows">
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_NetIncomeLoss" xlink:label="NetIncomeLoss" xlink:title="NetIncomeLoss"/>
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivities" xlink:label="NetCashProvidedByUsedInOperatingActivities" xlink:title="NetCashProvidedByUsedInOperatingActivities"/>
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="NetCashProvidedByUsedInOperatingActivities" xlink:to="NetIncomeLoss" use="optional" order="2" weight="1"/>
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ShareBasedCompensation" xlink:label="ShareBasedCompensation" xlink:title="ShareBasedCompensation"/>
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="NetCashProvidedByUsedInOperatingActivities" xlink:to="ShareBasedCompensation" use="optional" order="4" weight="1"/>
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_DepreciationAndAmortization" xlink:label="DepreciationAndAmortization" xlink:title="DepreciationAndAmortization"/>
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="NetCashProvidedByUsedInOperatingActivities" xlink:to="DepreciationAndAmortization" use="optional" order="5" weight="1"/>
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_UnrealizedGainLossOnInvestments" xlink:label="UnrealizedGainLossOnInvestments" xlink:title="UnrealizedGainLossOnInvestments"/>
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="NetCashProvidedByUsedInOperatingActivities" xlink:to="UnrealizedGainLossOnInvestments" use="optional" order="6" weight="-1"/>
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_IncreaseDecreaseInAccountsReceivable" xlink:label="IncreaseDecreaseInAccountsReceivable" xlink:title="IncreaseDecreaseInAccountsReceivable"/>
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="NetCashProvidedByUsedInOperatingActivities" xlink:to="IncreaseDecreaseInAccountsReceivable" use="optional" order="8" weight="-1"/>
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_IncreaseDecreaseInPrepaidExpense" xlink:label="IncreaseDecreaseInPrepaidExpense" xlink:title="IncreaseDecreaseInPrepaidExpense"/>
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="NetCashProvidedByUsedInOperatingActivities" xlink:to="IncreaseDecreaseInPrepaidExpense" use="optional" order="9" weight="-1"/>
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_IncreaseDecreaseInAccountsPayableAndAccruedLiabilities" xlink:label="IncreaseDecreaseInAccountsPayableAndAccruedLiabilities" xlink:title="IncreaseDecreaseInAccountsPayableAndAccruedLiabilities"/>
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="NetCashProvidedByUsedInOperatingActivities" xlink:to="IncreaseDecreaseInAccountsPayableAndAccruedLiabilities" use="optional" order="10" weight="1"/>
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_CashAndCashEquivalentsPeriodIncreaseDecrease" xlink:label="CashAndCashEquivalentsPeriodIncreaseDecrease" xlink:title="CashAndCashEquivalentsPeriodIncreaseDecrease"/>
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="CashAndCashEquivalentsPeriodIncreaseDecrease" xlink:to="NetCashProvidedByUsedInOperatingActivities" use="optional" order="11" weight="1"/>
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_ProceedsFromSaleAndMaturityOfMarketableSecurities" xlink:label="ProceedsFromSaleAndMaturityOfMarketableSecurities" xlink:title="ProceedsFromSaleAndMaturityOfMarketableSecurities"/>
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivities" xlink:label="NetCashProvidedByUsedInInvestingActivities" xlink:title="NetCashProvidedByUsedInInvestingActivities"/>
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="NetCashProvidedByUsedInInvestingActivities" xlink:to="ProceedsFromSaleAndMaturityOfMarketableSecurities" use="optional" order="13" weight="1"/>
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_PaymentsToAcquireMarketableSecurities" xlink:label="PaymentsToAcquireMarketableSecurities" xlink:title="PaymentsToAcquireMarketableSecurities"/>
    <link:calculationArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="NetCashProvidedByUsedInInvestingActivities" xlink:to="PaymentsToAcquireMarketableSecurities" use="optional" order="14" weight="-1"/>
    <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2014/elts/us-gaap-2014-01-31.xsd#us-gaap_PaymentsToAcquireIntangibleAssets" xlink:label="PaymentsToAcquireIntangibleAssets" xlink:title="PaymentsToAcquireIntangibleAssets"/>
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