Raccoons Reveal Hidden Diversity in Trabecular Bone Development.

Trabecular bone, and its ability to rapidly modify its structure in response to strain exerted on skeletal elements, has garnered increased attention from researchers with the advancement of CT technology that allows for the analysis of its complex lattice-like framework. Much of this research has focused on adults of select taxa, but analysis into trabecular development across ontogeny remains limited. In this paper, we explore the shift in several trabecular characteristics in the articular head of the humerus and femur in across the entirely of the species' lifespan.

Ultrahigh Sensitivity PTR-MS Instrument with a Well-Defined Ion Chemistry.

Proton-transfer-reaction mass spectrometry (PTR-MS) is widely used for measuring organic trace gases in air. In traditional PTR-MS, both nonpolar and polar analytes are ionized with unit efficiency, as predicted from ion-molecule collision theories. This well-defined ion chemistry allows for direct quantification of analytes without prior calibration and therefore is an important characteristic of PTR-MS.

Characterization of a Modulated X-ray Source for Ion Mobility Spectrometry.

As a highly deployed field instrument for the detection of narcotics, explosives, and chemical warfare agents, drift tube ion mobility spectrometry relies heavily upon the performance of the ionization source and mechanism of ion beam modulation. For this instrumental platform, ion chemistry plays a critical role in the performance of the instrument from a sensitivity and selectivity perspective; however, a range of instrumental components also occupy pivotal roles. Most notably, the mechanism of ion modulation or ion gating is a primary contributor to peak width in a drift tube ion mobility experiment.

Separation and Collision Cross Section Measurements of Protein Complexes Afforded by a Modular Drift Tube Coupled to an Orbitrap Mass Spectrometer.

New developments in analytical technologies and biophysical methods have advanced the characterization of increasingly complex biomolecular assemblies using native mass spectrometry (MS). Ion mobility methods, in particular, have enabled a new dimension of structural information and analysis of proteins, allowing separation of conformations and providing size and shape insights based on collision cross sections (CCSs). Based on the concepts of absorption-mode Fourier transform (aFT) multiplexing ion mobility spectrometry (IMS), here, a modular drift tube design proves capable of separating native-like proteins up to 148 kDa with resolution up to 45.

Implications of Blanc's Law for Use in Trapped Ion Mobility Spectrometry.

Blanc's Law has served as a way to predict the mobilities of ions in mixed drift gases for over 100 years yet has remained largely unexplored using newer ion mobility spectrometry (IMS) configurations, including traveling wave and trapped IMS (TIMS) systems. Here, we evaluate a drift-tube IMS (DTIMS) and compare it to a similar set of experiments performed in TIMS. We found that Blanc's Law can be applied in a DTIMS to determine the mobility of an analyte in the minor gas component of a ternary mixed drift gas system within 2% error.