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Objective: In future deep space exploration missions, crew will have to work more autonomously from Earth. Greater crew autonomy will increase dependence on automated systems. This study investigates the performance effects of different strategies to automate procedural work for space exploration operations., Background: The following strategies are investigated for performing procedural work:•  Manual Work uses no procedure automation and crew performs all actions.•  Shared Work uses procedure automation to perform some actions within a procedure while crew performs other actions.•  Supervised Work uses procedure automation to perform procedure actions while crew supervises the automation., Method: Twenty-seven participants participated in a planetary habitat scenario-based simulation using electronic procedures with automatable actions to investigate the effect of these strategies on situation awareness (SA) and workload. This study used a modification of the Situation Presence Assessment Method to measure SA and the Bedford Workload Scale to measure subjective workload., Results: Mean response times and accuracy for SA queries show no significant difference among the three strategies. Bedford Workload ratings compared across the three strategies indicate that participants rated their workload as highest in the Manual Work condition, followed by the Shared Work condition, and lowest in the Supervised Work condition., Conclusion: The study hypothesized that increased levels of automation would lead to lower subjective workload and decreased SA. Although no significant difference in SA was observed, subjective workload was lower in automation strategies. Based on subjective ratings, 93% of participants preferred some form of automation, with 56% preferring the Shared Work automation condition.

Human fetal antibody-dependent cellular cytotoxicity (ADCC) has not been reported previously. Most investigations have failed to document any cytolytic activity among fetal lymphocytes. The purpose of this study was to investigate ADCC activity in the human fetus and identify and characterize the effector cell populations in the fetus. Fetal spleen cells were separated into single-cell suspensions and assayed with 51Cr-labeled herpes simplex 1-infected Chang liver target cells. Significant ADCC activity was detected in 19 of 26 (73%) of freshly assayed fetal spleen cell preparations from fetuses of 17-24 wk gestational age. This activity, however, was significantly less than concurrently run adult peripheral blood mononuclear cells. After plastic adherence the fetal spleen ADCC activity from nonadherent cells was not significantly different from whole spleen preparations. Surprisingly, ADCC activity in nonadherent fetal cells dropped significantly after exposure to latex beads, an effect not seen in nonadherent adult lymphocytes. Thus, either fetal monocyte-derived (macrophages) fetal spleen cells do not efficiently adhere to plastic or a unique nonadherent population of latex-sensitive immunocytes is capable of mediating ADCC activity in the fetus. We suspect the former conclusion to be the more plausible; however, fluorescence-activated cell sorter staining of fetal cells was not sufficient to confirm these suspensions by fluorescence-activated cell sorter analysis.