Catlin Group's shares jumped on Friday after the insurance company was given a 'buy' rating by analysts at Espirito Santo Investment Bank Research following strong first half results. JPMorgan Chase & Co. reiterated an 'overweight' rating while Numis gave it an 'add' rating.Numis analyst Nick Johnson said that the shares are "currently undervalued [with] good potential upside".Pre-tax profits of $318m in the first six months of 2014 were over double last year's and "significantly ahead" of consensus estimates of $237m, Johnson said. Meanwhile geopolitical concerns weighed on travel stocks including tour operator Thomas Cook and its larger FTSE 100 peer TUI Travel.US President Barack Obama allowed limited air strikes against Sunni militants in Iraq to protect US personnel and Yazidi refugees who were stranded on a mountain. Russia has meanwhile imposed bans on food imports from the European Union and the US in retaliation of sanctions against Moscow for its insurgence in Ukraine. FTSE 250 - RisersCatlin Group Ltd. (CGL) 507.00p +4.26%Fidessa Group (FDSA) 2,151.00p +3.66%Petra Diamonds Ltd.(DI) (PDL) 192.60p +3.55%Kazakhmys (KAZ) 312.40p +3.41%Laird (LRD) 290.90p +2.57%Euromoney Institutional Investor (ERM) 1,057.00p +2.52%Home Retail Group (HOME) 180.30p +2.44%Rank Group (RNK) 165.00p +2.42%Exova Group (EXO) 220.90p +2.36%Hellermanntyton Group (HTY) 303.00p +2.30%FTSE 250 - FallersPets at Home Group (PETS) 181.00p -4.84%Enterprise Inns (ETI) 113.90p -2.98%Thomas Cook Group (TCG) 114.90p -2.96%Dixons Carphone (DC.) 327.20p -2.91%Henderson Group (HGG) 221.90p -2.68%Man Group (EMG) 109.40p -2.58%ITE Group (ITE) 190.50p -2.46%Ophir Energy (OPHR) 203.90p -2.16%Cobham (COB) 289.30p -2.16%Aveva Group (AVV) 1,947.00p -2.16%RD