Veber’s Rules in Terahertz Light

Background: The Attenuated Total Reflection (ATR) technique of spectroscopy in combination using the terahertz technique is being investigated to find rotatable bonds, which are considered as one of the rules of thumb given by Veber et al.. Results: Histidine, as one of the most studied pharmacological preparations, is used in an experiment to test our research. Three rotatable bonds have been found and thus the results published in pharmaceutical data guides have been confirmed. Conclusion: The results are obtained in a terahertz spectrometer equipped with a Dove prism, where an ATR technique is applied. The samples in two forms, polycrystalline and as a solution in alcohol, are used to check the methodology. Histidine molecules, dissolved in alcohol and thus freed from intermolecular bonds, exposed the rotations around the three bonds. Thus, the validity of the ATR-THz research methodology used in the search for rotating bonds in drug candidates molecules is confirmed. The goal of the method presented in the paper is to support pharmacological research, and pharmaceutical industry, as well.

Simulation of Extrasolar Planet Detection with Rotationally Shearing Interferometer at 10 µm

We simulate the interferometric fringe patterns for the case of an extrasolar planet system with two planets. We show that the incidence distributions become more complicated, yet their interpretation is feasible. The generalized fringe distributions rotate when the Dove prism is rotated. Likewise, the number of fringes changes with the angle of rotation of the Dove prism.

Применение терагерцовой спектроскопии для in vivo исследования динамики развития лимфедемы -=SUP=-*-=/SUP=-

A laboratory model of lymphedema development induced by lymphatic vessel resection in rat extremities is presented. In vivo analysis of lymphedema development (monitoring for 4 weeks) employed reflective terahertz spectroscopy with a Dove prism. The incidence angle for an s -polarized electromagnetic wave directed to the boundary of the prism and the biological tissue was close to the Brewster’s angle. Significant changes in the spectral characteristics of the tissue in the animals’ extremities were detected on days 21–28 of lymphedema development. A predictive model for disease diagnostics based on monitoring the changes of the tissue absorbance curve in the 0.4–1.1 THz range was constructed. Principal component analysis and support vector machines were used in the model.

When Photons Are Lying about Where They Have Been

The history of photons in a nested Mach–Zehnder interferometer with an inserted Dove prism is analyzed. It is argued that the Dove prism does not change the past of the photon. Alonso and Jordan correctly point out that an experiment by Danan et al. demonstrating the past of the photon in a nested interferometer will show different results when the Dove prism is inserted. The reason, however, is not that the past is changed, but that the experimental demonstration becomes incorrect. The explanation of a signal from the place in which the photon was (almost) not present is given. Bohmian trajectory of the photon is specified.