Bethel, Jeff | Search NASA

DOE OSTI2018

Cross sectional association of arsenic and seroprevalence of hepatitis B infection in the United States (NHANES 2003–2014)

Highlights: • Serology tests discern between hepatitis B infections and hepatitis B vaccinations. • Urinary arsenic concentrations are used as a biomarker of recent exposure. • Arsenic biomarkers were linked to serology indicative of hepatitis B infection. Arsenic alters immunological parameters including antibody formation and antigen-driven T-cell proliferation.

54 ENVIRONMENTAL SCIENCES↗

NASA NTRS1991

Gripper for truss structure assembly

The CIRSSE two-finger gripper is designed to be used with a 6-axis wrist-mounted force-torque sensor as part of an experimental testbed for cooperative robotic manipulation. The gripper system consists of a dedicated controller and a pneumatic powered gripper that is servoed in position or grasping force. The gripper also has a between fingertip light beam sensor. The major features of this new design are: high grasping force to weight ratio (25::1) and compactness (14 cm base-fingertip, 0.8 kilograms); low cost dedicated slave controller; and simple host-controller communications protocol to minimize command interpretation delay. Shared software functions between the host and the controller processor permit the host to select servo mode, servo gain-parameter values, and calibration offsets. Hidden primitive self-test, calibration and servo confidence functions are included.

Kelley, Robert B.↗