Six thermo-activated transient receptor potential (TRP) channels are the molecular basis of the thermosensation for mammals. But the molecular source of their gating remains unknown. In the Letter, we suggest a physically based model for the TRP chan
nels and show that the temperature dependence of the internal friction can be a key factor governing the ion channels gating. Results of the computer modeling allowed us to successfully reproduce the experimental data for the open probability Popen of the TRPV1 and TRPM8 channels at different temperatures and voltages.
The temperature effect on the cardiac ryanodine receptor (RyR) function has been studied within the electron-conformational (EC) model. It is shown that simple EC model with the Arrhenius like temperature dependence of internal and external frictions
and a specific thermosensitivity of the tunnelling open - close transitions can provide both qualitative and quantitative description of the temperature effects for isolated RyRs. The potential of the model was illustrated by explaining the experimental data on the temperature dependence of sheeps isolated cardiac RyR gating and conductance (R. Sitsapesan et al., J Physiol 434, 469 (1991)).
We present an overview of the microscopic theory of the Dzyaloshinskii-Moriya (DM) coupling in strongly correlated 3d compounds. Most attention in the paper centers around the derivation of the Dzyaloshinskii vector, its value, orientation, and sense
(sign) under different types of the (super)exchange interaction and crystal field. We consider both the Moriya mechanism of the antisymmetric interaction and novel contributions, in particular, that of spin-orbital coupling on the intermediate ligand ions. We have predicted a novel magnetic phenomenon, {it weak ferrimagnetism} in mixed weak ferromagnets with competing signs of the Dzyaloshinskii vectors. We revisit a problem of the DM coupling for a single bond in cuprates specifying the local spin-orbital contributions to Dzyaloshinskii vector focusing on the oxygen term. We predict a novel puzzling effect of the on-site staggered spin polarization to be a result of the on-site spin-orbital coupling and the the cation-ligand spin density transfer. The intermediate ligand NMR measurements are shown to be an effective tool to inspect the effects of the DM coupling in an external magnetic field. We predict the effect of a $strong$ oxygen weak antiferromagnetism in edge-shared CuO$_2$ chains due to uncompensated oxygen Dzyaloshinskii vectors. We revisit the effects of symmetric spin anisotropy directly induced by the DM coupling. A critical analysis will be given of different approaches to exchange-relativistic coupling based on the cluster and the DFT based calculations. Theoretical results are applied to different classes of 3d compounds from conventional weak ferromagnets ($alpha$-Fe$_2$O$_3$, FeBO$_3$, FeF$_3$, RFeO$_3$, RCrO$_3$,.. ) to unconventional systems such as weak ferrimagnets (e.g., RFe$_{1-x}$Cr$_x$O$_3$), helimagnets (e.g., CsCuCl$_3$), and parent cuprates (La$_2$CuO$_4$,...).
The Loewdin orthogonalization procedure being the well-known technique, particularly in quantum chemistry, however, gives rise to novel effects missed in earlier studies. Making use of the technique of irreducible tensorial operators we have develope
d a regular procedure for account of the orthogonalization effects. For illustration we address the emergence of a specific magnetoelectric coupling for noncentrosymmetric 3d or 4f ions.
The incommensurate (IC) spin ordering in quasi-1D edge-shared cuprate NaCu_2O_2 has been studied by ^{23}Na nuclear magnetic resonance spectroscopy in an external magnetic field near 6 Tesla applied along the main crystallographic axes. The NMR lines
hape evolution above and below T_Napprox12 K yields a clear signature of an IC static modulation of the local magnetic field consistent with a Cu^{2+} spin spiral polarized in the bc-plane rather than in the ab-plane as reported from earlier neutron diffraction data.
