Pre-exposure prophylaxis (PrEP) is a course of HIV drugs taken daily by HIV negative people most at risk of HIV to reduce their risk of HIV infection. Truvada is currently the only drug approved for use as PrEP. Truvada is a single pill that is a combination of two anti-HIV drugs, tenofovir and emtricitabine.
Astronomical spectroscopy is one of the most powerful tools used by astronomers to gain a fundamental understanding of our universe. Astronomical spectroscopy is a technique in which the absorption and emission of electromagnetic radiation from stars and other celestial objects are studied.he absorption and or emission spectra of a molecule generally consist of a number of lines. These lines correspond to the discrete differences in the internal energy modes of a molecule.
An invaluable tool in organic structure determination and verification involves the class of electromagnetic (EM) radiation with frequencies between 4000 and 400 cm -1 (wavenumbers). The category of EM radiation is termed infrared (IR) radiation, and its application to organic chemistry known as IR spectroscopy.hus IR spectroscopy involves collecting absorption information and analyzing it in the form of a spectrum -- The frequencies at which there are absorptions of IR radiation (peaks or signals) can be correlated directly to bonds within the compound in question.