Permanental vectors

A permanental vector is a generalization of a vector with components that are squares of the components of a Gaussian vector, in the sense that the matrix that appears in the Laplace transform of the vector of Gaussian squares is not required to be either symmetric or positive definite. In addition, the power of the determinant in the Laplace transform of the vector of Gaussian squares, which is −1/2, is allowed to be any number less than zero.     

Replacement of a proline with silaproline causes a 20-fold increase in the cellular uptake of a Pro-rich peptide

The results presented here show that elementary design enhancements have led to a 20-fold increase in the cellular uptake properties of a Pro-rich cell-penetrating peptide. These results are relevant not only due to the increasing interest in using CPPs as molecular shuttles for intracellular drug delivery but also because they illustrate the power of combining conformational analysis with rational design to modulate the behavior of biologically active compounds.     

Measurement of the absorption coefficient of scattering liquid media by the calorimetric method

Using the example of a number of hydrosols (gold nanorods and nanoshells, silver nanoshells, zinc phthalocyanine nanoparticles), we show that the absorption coefficient of a scattering liquid medium can be measured from its heating by a short-time laser irradiation. The degree of heating was determined from expansion of the liquid in an ampoule with a capillary (the principle of liquid thermometer). Irradiation was performed at a wavelength of 671 or 1069 nm. From the transmission of samples of hydrosols at these wave-lengths, the sum of the absorption and scattering coefficients has been determined. To measure the absorption spectra of scattering liquids by this method, a laser with a tunable radiation wavelength is required. In the case of monodisperse colloidal solutions, the method ensures the measurement of the absorption and scattering cross-section ratio of particles.