The interactions of the antihypertensive AT(1) antagonists candesartan and losartan with membrane bilayers were studied through the application of DSC, Raman, and solid state (31)P NMR spectroscopies. (1)H and (13)C NMR resonances of candesartan were assigned on the basis of 1D and 2D NMR spectroscopy. A (31)P CP NMR broadline fitting methodology in combination with ab initio computations was implemented and, in conjunction with DSC and Raman results, provided valuable information regarding the perturbation, localization, orientation, and dynamic properties of the drugs in membrane models. In particular, results indicate that losartan anchors in the mesophase region of the lipid bilayers with the tetrazole group oriented toward the polar headgroup, whereas candesartan has less definite localization spanning from water interface toward the mesophase and upper segment of the hydrophobic region. Both sartan molecules decrease the mobilization of the phospholipids alkyl chains. Losartan exerts stronger interactions compared with candesartan, as depicted by the more prominent thermal, structural, and dipolar (1)H-(31)P changes that are caused in the lipid bilayers. At higher concentrations, candesartan strengthens the polar interactions and induces increased order at the bilayer surface. At the highest concentration used (20 mol %), only losartan induces formation of microdomains attributed to the flexibility of its alkyl chain. These results in correlation to reported data with other AT(1) antagonists strengthen the hypothesis that this class of molecules may approach the active site of the receptor by insertion in the lipid core, followed by lateral diffusion toward the binding site. Further, the similarities and differences of these drugs in their interactions with lipid bilayers establish, at least in part, their pharmacological properties.

We have theoretically examined the scaling of the Al2O3/InAlAs/InGaAs QW FET one of the proposed III-V channel MOSFET's designed to replace the conventional SiO2/Si structures. To accomplish this we have used a Schroedinger – Poisson – Continuity equation model that is fully 2-dimentional ie all equations are solved along and perpendicular to the channel. We have found out that for the threshold voltage VT to be around zero volts a Schottky barrier ΦΒ of 3.5 - 4.0eV is necessary. Both Cu or W will suffice. for this. The VT value moves by 0.7 as the device is scaled from 65 nm gate length Lg to 25nm. Furthermore, as the Lg is scaled to the desired 20nm value the subthreshold slope SS increases from 90meV/dec to about 170meV/dec guaranteeing fast switching.

It was recently shown that the quantum mechanical results of the Landauer theory of conduction, applied to a simple one-layer channel FET, can be recast in the traditional drift-diffusion form but with the mobility and injection velocity redefined in a new context. Based on that, we have performed two-dimensional Poisson-Schrödinger-Continuity calculations for both long drift-diffusion and short ballistic quantum well FETs. Very good agreement with many-layer, state-of-the-art InGaAs devices has been achieved provided that only one parameter, the saturation velocity υsat of the mobility function, is rescaled so that our calculated drain current agrees with the experimental value at very large gate voltages VG. This single value of υsat has been used at all other VG. Our calculations are not only a test of the equivalence described above but valuable information about the sub-threshold regime and especially the leakage currents is obtained. This information is usually absent in rigorous Landauertype-or equivalently non-equilibrium Green functions-calculations which are performed in simplified FET systems.

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