Magnetic resonance(About magnetic resonance freqency)

Hi, I have some problems understanding magnetic resonance, especially calculating magnetic resonance freqency.

There is a interesting paper about transfering power magnetically for long distance which is the Science paper ‘Wireless power transfer via strongly coupled magnetic resonances’ published at 2007.

So my question is

1. In the paper, resonant frequency of lumped device is described 1/(2*pi*sqrt(L*C)).
Are the value L, C evaluated or measured at frequency 0 or resonant frequency? Or the frequency doesn’t make the change of 1/(2*pi*sqrt(L*C))?

2. And is resonant frequency ,the frequency which can transfer the maximum power to load, is the same as self resonant frequency of coil?
It’s a bit curious that at resonant frequency, the value of resistance increases by a lager factor than that of inductance which causes decrease in Q.

I have some difficulties understanding what is magnetic resonance physically,
and the difference bwt magnetic resonance in trans/recie coil and electrical resonance in circuit.

Will you share the paper?