The goal of the work was to study female tolerance of g-loads before and after simulated weightlessness, and evaluate the effectiveness of countermeasures and anti-g means proposed for space flight. Centrifuge with a 7.25 m arm was used for 29 runs of 8 female subjects. The subjects were exposed to the transverse loads (+GX) at 8.2 g on a special regimen with the total run time of 9 min to simulate the ballistic descent from orbit in a SOYUZ-TM vehicle. Baseline tolerance of the females to transverse loads up to +8GX was good and satisfactory. Following 120 days of bed rest without the countermeasures or the anti-g suit g-tolerance was significantly lowered as evidenced by visual disorders in 67% of cases and exaggerated, if compared with the pre-hypokinesia levels, heart and respiration rates, i.e. 20% and 23.5%, respectively. The countermeasures and anti-g suit Centaur maintained g-tolerance at essentially the baseline level and precluded visual disorders. Results of the study speak in favor of the countermeasures and anti-g means used by the females in simulated long-duration weightlessness which can be recommended for the final phase of extended space mission.
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There is continued interest in acceleration (G) effects in civil aviation, as G-induced loss of consciousness (G-LOC), impaired consciousness, and visual effects play a role in aerobatic, agricultural, and military aviation accidents. A software model [the Civil Aerospace Medical Institute G-Effects Model (CGEM)] based on physical and physiological variables related to in-flight tissue resupply and using oxygen flow as a proxy for supply availability, was developed to evaluate risk of G-LOC and related phenomena in aeronauts. Aeronauts were modeled using several parameters, including sex, cardiovascular fitness, and other common modifiers such as G-suits, positive pressure breathing gear, anti-G straining, and other muscle tensing.
View Article and Find Full Text PDFPLoS Pathog
April 2016
Division of Viral Products, Center for Biologics Evaluation and Research (CBER), FDA, Silver Spring, Maryland, United States of America.
Respiratory Syncytial Virus (RSV) is the major cause of pneumonia among infants. Here we elucidated the antibody repertoire following primary RSV infection and traced its evolution through adolescence and adulthood. Whole genome-fragment phage display libraries (GFPDL) expressing linear and conformational epitopes in the RSV fusion protein (F) and attachment protein (G) were used for unbiased epitope profiling of infant sera prior to and following RSV infection.
View Article and Find Full Text PDFAnnu Int Conf IEEE Eng Med Biol Soc
August 2015
G-Induced Loss of Consciousness (G-LOC) is mainly caused by the sudden acceleration in the direction of +Gz axis from the fighter pilots, and is considered as an emergent situation of which fighter pilots are constantly aware. In order to resist against G-LOC, fighter pilots are subject to run Anti-G straining maneuver (AGSM), which includes L-1 respiration maneuvering and muscular contraction of the whole body. The purpose of this study is to create a G-LOC warning alarm prior to G-LOC by monitoring the Electromyogram (EMG) of the gastrocnemius muscle on the calf, which goes under constant muscular contraction during the AGSM process.
View Article and Find Full Text PDFAviat Space Environ Med
September 2009
Department of Computer Application, Fourth Military Medical University, Xi'an, China.
Background: The push-pull maneuver (PPM) can lead to loss of consciousness in pilots of high-performance aircraft. Modeling of the physical and physiological aspects of this phenomenon should allow improved countermeasures.
Methods: A structurally based mechanistic computer model was developed to incorporate dynamic carotid baroreflex responses and detailed modeling of vessel segments for different anatomic regions.
Analysis of +Gx tolerance of 15 members of short-term ISS missions and 9 members of long-term ISS missions aboard the Soyuz vehicles showed good tolerance during insertion and satisfactory during descent provided the use of in-flight countermeasures and anti-g suit Kentaur inside the vehicle. Objective data about the tolerance of off-nominal +Gx (6.26 and 8.
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