Presentation, clinical course and complications in trauma patients with concomitant COVID-19 infection.

BACKGROUND: This study investigated the impact of COVID-19 infection on hospitalized trauma patients. METHODS: A retrospective review of hospitalized trauma patients at a level I trauma center was performed from March-December 2020. Data pertaining to patient demographics, presentation and hospital course was compared between COVID positive and negative trauma patients. RESULTS: There were 4,912 patients and 179 (3.64%) were COVID-19 positive. Demographics and clinical presentation did not differ significantly between those with and without concomitant COVID-19. However, COVID positive trauma patients had higher rates of acute kidney injury (p = 0.016), sepsis (p = 0.016), unplanned intubation (p = 0.002) and unplanned return to the ICU (p = 0.01). The COVID positive cohort also had longer hospital stays (p < 0.01) with no significant difference in mortality. CONCLUSIONS: In the setting of an ongoing pandemic, awareness of the complications COVID positive trauma patients are predisposed to is important for providers.

Selected area polishing for precision TEM sample preparation.

A selected area mechanical polishing technique has been developed to improve the precision of cross-sectional TEM sample preparation, based upon the early work of Benedict and colleagues [Benedict et al. (1990) MRS Symp. Proc. Vol. 199, p. 189]. TEM samples were made from a pre-selected section through the middle of a 1 micron wide band of transistors extending laterally for more than 1 mm by precise control over the plane of polish with a corresponding reduction in sample preparation time. To illustrate the application of this technique, a uniformly thin, electron transparent TEM sample of a single, specific, failed transistor is obtained from a 4 mm by 10 mm device array.

Direct electron microscopy studies of the bone-hydroxylapatite interface.

The bone-hydroxylapatite interface has been examined directly in the transmission electron microscope (TEM). The bone-hydroxylapatite interface was characterized by using several electron microscopy techniques, including bright and dark field imaging, electron diffraction, high-resolution imaging, and energy dispersive analysis in the scanning-transmission electron microscope (STEM EDS). Mechanical grinding followed by argon-ion milling produced interface regions of unstained and undecalcified rat bone and hydroxylapatite that were transparent to electrons. Thus the exact location of the interface could be established and the bone at the interface studied. Conventional and high-resolution imaging in the TEM demonstrated direct chemical bonding between bone and hydroxylapatite. The bone at the ceramic surface was the same as normal bone away from the interface.