Asteroid Retrieval Feasibility Study

This report describes the results of a study sponsored by the Keck Institute for Space Studies (KISS) to investigate the feasibility of identifying, robotically capturing, and returning an entire Near-Earth Asteroid (NEA) to the vicinity of the Earth by the middle of the next decade. The KISS study was performed by people from Ames Research Center, Glenn Research Center, Goddard Space Flight Center, Jet Propulsion Laboratory, Johnson Space Center, Langley Research Center, the California Institute of Technology, Carnegie Mellon, Harvard University, the Naval Postgraduate School, University of California at Los Angeles, University of California at Santa Cruz, University of Southern California, Arkyd Astronautics, Inc., The Planetary Society, the B612 Foundation, and the Florida Institute for Human and Machine Cognition

Factors associated with humeral avulsion of glenohumeral ligament lesions in patients with anterior shoulder instability: An analysis of the MOON shoulder instability cohort

BACKGROUND: Humeral avulsion of the glenohumeral ligament (HAGL) lesions are an uncommon cause of anterior glenohumeral instability and may occur in isolation or combination with other pathologies. As HAGL lesions are difficult to detect via magnetic resonance imaging (MRI) and arthroscopy, they can remain unrecognized and result in continued glenohumeral instability. PURPOSE: To compare patients with anterior shoulder instability from a large multicenter cohort with and without a diagnosis of a HAGL lesion and identify preoperative physical examination findings, patient-reported outcomes, imaging findings, and surgical management trends associated with HAGL lesions. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: Patients with anterior glenohumeral instability who underwent surgical management between 2012 and 2020 at 11 orthopaedic centers were enrolled. Patients with HAGL lesions identified intraoperatively were compared with patients without HAGL lesions. Preoperative characteristics, physical examinations, imaging findings, intraoperative findings, and surgical procedures were collected. The Student RESULTS: A total of 21 HAGL lesions were identified in 915 (2.3%) patients; approximately one-third (28.6%) of all lesions were visualized intraoperatively but not identified on preoperative MRI. Baseline characteristics did not differ between study cohorts. Compared with non-HAGL patients, HAGL patients were less likely to have a Hill-Sachs lesion (54.7% vs 28.6%; CONCLUSION: Approximately one-third of HAGL lesions were missed on preoperative MRI. HAGL patients were less likely to exhibit preoperative imaging findings associated with anterior shoulder instability, such as Hill-Sachs lesions or anterior labral pathology. These patients underwent open procedures more frequently than patients without HAGL lesions

A method for the chemical synthesis of 14C-labeled fatty acyl coenzyme A's of high specific activity

A simple and reliable method, based on that described by W. Seubert (1960, Biochem Prep. 7, 80-83), has been developed for the chemical synthesis of radioactive acyl coenzyme A's. 1-14C-labeled fatty acids (palmitic, oleic, and linoleic) are converted to their acyl chlorides with oxalyl chloride. The [1-14C]acyl chlorides are then condensed with a two- to three-fold molar excess of coenzyme A in a bicarbonate-buffered tetrahydrofuran solution to form the corresponding [1-14C]acyl coenzyme A's. The overall yields are near 75%, and the purities are greater than 90% based on spectral, chromatographic, and enzymatic properties.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/23182/1/0000109.pd

Application of life-cycle energy analysis to photovoltaic module design

This paper highlights results from a collaborative life-cycle design project between the University of Michigan, the US Environment Protection Agency and United Solar Systems Corporation. Energy analysis is a critical planning and design tool for photovoltaic (PV) modules. A set of model equations for evaluating the life-cycle energy performance of PV systems and other electricity-generating systems are presented. The total PV life-cycle, encompassing material production, manufacturing and assembly, use and end-of-life management, was investigated. Three metrics—energy payback time, electricity production efficiency and life-cycle conversion efficiency—were defined for PV modules with and without balance-of-system (BOS) components. These metrics were evaluated for a United Solar UPM-880 amorphous silicon PV module based on average insolation in Detroit, Boulder and Phoenix. Based on these metrics, a minimum condition for assessing the sustainability of electricity-generating systems was proposed and discussed. The life-cycle energy analysis indicated that the aluminum frame is responsible for a significant fraction of the energy invested in the UPM-880 module. © 1997 John Wiley & Sons, Ltd.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/35191/1/169_ftp.pd