Sex differences in olfactory behavior and neurophysiology in Long Evans Rats.

In many species, olfactory abilities in females are more acute than those in males. Studies in humans show that women have lower olfactory thresholds and are better able to discriminate and identify odors than men. In mice, odorants elicit faster activation from a larger number of olfactory bulb glomeruli in females than males.

Dynamic conformational equilibria in the active states of KRAS and NRAS.

The design of potent RAS inhibitors benefits from a molecular understanding of the dynamics in KRAS and NRAS and their oncogenic mutants. Here we characterize switch-1 dynamics in GTP-state KRAS and NRAS by P NMR, by N relaxation dispersion NMR, hydrogen-deuterium exchange mass spectrometry (HDX-MS), and molecular dynamics simulations. In GMPPNP-bound KRAS and NRAS, we see the co-existence of two conformational states, corresponding to an "inactive" state-1 and an "active" state-2, as previously reported.

Real-Time In Vivo Human Skin Testing Using a Handheld Fourier Transform Infrared Spectrometer with a Three-Bounce Two-Pass Attenuated Total Reflection Interface.

Attenuated total reflection (ATR) Fourier transform infrared spectroscopy (FT-IR) is used to characterize a vast array of materials at the molecular level in various industry types. Here we compare the performance of a portable spectrometer with a novel three-bounce-two-pass (3B2P) ATR scanning interface to the same device with a standard one-bounce (1B) ATR, and to a benchtop spectrometer with a 10-bounce (10B) ATR, in ideal sample-interface conditions and an applied dermatological study setting. In both application settings, the benchtop 10B ATR interface showed the highest signal-to-noise ratio (SNR), however, the novel 3B2P produced a six-fold increase in the sensitivity of the portable spectrometer when analyzing isopropanol and showed the greatest consistency of SNR of all devices when analyzing isopropanol and in vivo skin samples.

Mapping the FF domain folding pathway via structures of transiently populated folding intermediates.

Despite the tremendous accomplishments of AlpaFold2/3 in predicting biomolecular structure, the protein folding problem remains unsolved in the sense that accurate atomistic models of how protein molecules fold into their native conformations from an unfolded ensemble are still elusive. Here, using chemical exchange saturation transfer (CEST) NMR experiments and a comprehensive four-state kinetic model of the folding trajectory of a 71 residue four-helix bundle FF domain from human HYPA/FBP11 we present an atomic resolution structure of a transiently formed intermediate, I2, that along with the structure of a second intermediate, I1, provides a description of the FF domain folding trajectory. By recording CEST profiles as a function of urea concentration the extent of compaction along the folding pathway is evaluated.