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Abstract Electrospray ionization is widely used to generate vapor phase ions for analysis by mass spectrometry in proteomics research. However, only a small fraction of the analyte enters the mass spectrometer due to losses that are fundamentally linked to the use of a background gas to stimulate the generation of ions from electrosprayed droplets. Here we report a nanopore ion source that delivers ions directly into high vacuum from aqueous solutions. The ion source comprises a pulled quartz pipette with a sub-100 nm opening. Ions escape an electrified meniscus by ion evaporation and travel along collisionless trajectories to the ion detector. We measure mass spectra of 16 different amino acid ions, post-translationally modified variants of glutathione, and the peptide angiotensin II, showing that these analytes can be emitted as desolvated ions. The emitted current is composed of ions rather than charged droplets, and more than 90% of the current can be recovered in a distant collector.

Background:. Despite the relatively high incidence of phalangeal fractures, there is an imperfect understanding of the epidemiology and anatomical distribution of these fractures. This study describes the patient characteristics, anatomic distribution, and detailed fracture patterns of phalangeal fractures among a large adult cohort in the United States. Methods:. A retrospective study was performed among patients with phalangeal fractures in the United States between January 2010 and January 2015. Included patients were 18 years old or older and had a diagnosis of a phalangeal fracture. A total of 2140 phalangeal fractures in 1747 patients were included, and a manual chart review was performed to collect epidemiological and radiographic information. Fractures were classified based on location and fracture pattern. Results:. The median age at the time of injury was 45 years (interquartile range, 30–57), and 65% of patients were men. The small finger had the highest incidence of fractures (26%) followed by the ring finger (24%). Distal and proximal phalanges demonstrated the highest incidence of fractures at 39% each. The dominant hand was affected in 44% of cases. Eighteen percent of fractures were due to a work-related trauma mechanism, and the most common mechanism of injury was blunt trauma (46%). Conclusion:. This study provides a detailed overview of the anatomic distribution and fracture patterns of phalangeal fractures in an adult US population and, thus, may aid hand surgeons treating these injuries.

Cardiac perfusion PET is increasingly used to assess ischemia and cardiovascular risk and can also provide quantitative myocardial blood flow (MBF) and flow reserve (MBFR) values. These have been shown to be prognostic biomarkers of adverse outcomes, yet MBF and MBFR quantification remains underutilized in clinical settings. We compare MBFR to traditional cardiovascular risk factors in a large and diverse clinical population (60% African-American, 35.3% Caucasian) to rank its relative contribution to cardiovascular outcomes. Major adverse cardiovascular events (MACE), including unstable angina, non-ST and ST-elevation myocardial infarction, stroke, and death, were assessed for consecutive patients who underwent rest-dipyridamole stress 82Rb PET cardiac imaging from 2012-2015 at the Hospital of the University of Pennsylvania (n = 1283, mean follow-up 2.3 years). Resting MBF (1.1 ± 0.4 ml/min/g) was associated with adverse cardiovascular outcomes. MBFR (2.1 ± 0.8) was independently and inversely associated with MACE. Furthermore, MBFR was more strongly associated with MACE than both traditional cardiovascular risk factors and the presence of perfusion defects in regression analysis. Decision tree analysis identified MBFR as superior to established cardiovascular risk factors in predicting outcomes. Incorporating resting MBF and MBFR in CAD assessment may improve clinical decision making.