▁the ▁L ix is cope ▁port able ▁x - ray ▁imag ing ▁system , ▁also ▁known ▁as ▁the ▁L ix i ▁Profil er . ▁In ▁nuclear ▁medicine , ▁it ▁serves ▁to ▁cal ibr ate ▁the ▁equipment ▁needed ▁like ▁single - ph ot on ▁emission ▁computed ▁tom ography ▁systems ▁( S PE CT ) ▁to ▁make ▁x - ray s . ▁It ▁ens ures ▁that ▁the ▁machines ▁work ▁correctly ▁to ▁produce ▁images ▁of ▁radio is ot ope ▁distribution ▁inside ▁the ▁patient . ▁This ▁is ot ope ▁is ▁produced ▁in ▁a ▁nuclear ▁re actor ▁from ▁europ ium ▁or ▁en rich ed ▁g ad olin ium . ▁It ▁can ▁also ▁detect ▁the ▁loss ▁of ▁calci um ▁in ▁the ▁hip ▁and ▁back ▁b ones , ▁allowing ▁the ▁ability ▁to ▁diagn ose ▁o ste op or osis . ▁ ▁G ad olin ium - 1 4 8 ▁would ▁be ▁ideal ▁for ▁radio is ot ope ▁therm oe lect ric ▁gener ators ▁due ▁to ▁its ▁ 7 4 - year ▁half - life , ▁high ▁density , ▁and ▁dominant ▁alpha ▁decay ▁mode . ▁However , ▁g ad olin ium - 1 4 8 ▁cannot ▁be ▁econom ically ▁synth es ized ▁in ▁sufficient ▁quantities ▁to ▁power ▁a ▁R T G . ▁ ▁List ▁of ▁is ot op es ▁▁ ▁| - ▁| ▁ 1 3 4 G d ▁| ▁style =" text - align : right " ▁| ▁ 6 4 ▁| ▁style =" text - align : right " ▁| ▁ 7 0 ▁| ▁ 1 3 3 .