THE HUMAN RESEARCH PROGRAM DIRECTED PROPOSAL TITLED VENOUS CONGESTION COUNTERMEASURE STUDY (PI: M. STENGER) WAS GIVEN AUTHORITY TO PROCEED IN JULY 2018 BUT FUNDING WAS NOT ACTIVATED UNTIL OCTOBER 2018 (ATP LETTER IS INCLUDED IN THIS PACKAGE). THIS STATEMENT OF WORK COVERS THE PORTION OF ACTIVITIES TO BE PERFORMED BY THE UNIVERSITY OF TEXAS SOUTHWESTERN MEDICAL CENTER (CO-I: B. LEVINE) TO IMPLEMENT THE STUDY AS DEFINED IN THE ATTACHED PROTOCOL. BACKGROUND: THIS STUDY WAS DIRECTED BY THE HUMAN RESEARCH PROGRAM AND INCLUDES THE INVOLVEMENT OF TWO EXTERNAL CO-INVESTIGATORS. IN ORDER TO SAVE SIGNIFICANT INDIRECT COSTS GRANTS WITH THE TWO CO- INVESTIGATORS ARE TO BE ESTABLISHED DIRECTLY WITH THEIR ASSOCIATED INSTITUTIONS. THE CONTRACTOR IS AUTHORIZED TO PROCEED WITH IMPLEMENTATION OF THIS EXPERIMENT AS DESCRIBED IN THE PROPOSAL BELOW. HOWEVER NO TESTING WITH HUMAN SUBJECTS IS ALLOWED UNTIL THE PROTOCOL HAS BEEN REVIEWED AND APPROVED NASA S INSTITUTIONAL REVIEW BOARD (IRB) HTTP://IRB.NASA.GOV/. THE PERIOD OF PERFORMANCE IS EXPECTED TO BEGIN IN OCTOBER 2018 AND EXTEND FOR 2 YEARS THROUGH SEPTEMBER 2020.