Possible Clues:

• May it be with John Tanner, thought Shaw
• Bloodsuckers absorbing iron for vital energy
• Vital power
• One translation of 'qi'
• Prison term for going to church? That's the spirit!
• Elan vital
• Time in prison for group creates a passion for living
• Inner self
• American in seven is hero of nineteen twenty five German novel
• 'What - - for these who die as cattle?' (Wilfred Owen)