Many types of muscular dystrophy can also reduce the efficiency of the heart muscle.

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These left-ventricular leads are intended to improve the efficiency of the heart in patients with heart failure, but are not responsible for delivering immediate life-sustaining pacing or life-saving defibrillation therapy.

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While The Times's Will Hodgkinson said the opening night "demonstrated that it is imagination and the power of art, combined with ruthless technological efficiency, that is at the heart of Kraftwerk's magic".

BBC: Kraftwerk kick off Tate Modern retrospective

Efficiency may be at the heart of all great products, but capturing customer stories is what matters most.

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Science and technology are at the heart of expanding the universe of clean energy options and increasing the efficiency of transmission and generation.

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