Real-Time Quantification of Size-Resolved Bioaerosols and Inert Particles in Spacecraft Assembly Facilities at the NASA Jet Propulsion Laboratory.

Abstract Responsible space exploration is a cornerstone of planetary protection, particularly at sites in the Solar System with a high potential for the existence of extant life. To limit bioburden, spacecraft assembly occurs in cleanroom facilities. Cleanroom levels are established through air particulate counters that can assess particle size distribution and concentration but cannot detect bioaerosols. Additionally, these devices do not detect in real-time, which poses a risk to critical flight hardware assemblies or even mission timelines. A first-of-its-kind study was conducted to simultaneously detect bioaerosols, inert particles, and their size distribution in real-time in operational spacecraft assembly cleanrooms at NASA's Jet Propulsion Laboratory in Pasadena, CA, USA, using the BioVigilant IMD-A® 350 (Azbil Corporation, Tucson, AZ, USA). The IMD-350A continuously sampled during operations and no-operation 6 h intervals in two facilities per cleanroom class: ISO 6, ISO 7, and ISO 8. A positive correlation was established between human presence in the cleanroom and elevated bioaerosol counts. Smaller particles of sizes 0.5 and 1 µm constituted an average ∼91% of the total bioaerosols detected in At Work intervals across all ISO classes observed. The results of this study were used to establish bioburden particulate thresholds for the most stringent JPL cleanrooms used in the assembly of the Sample Caching System for the Mars 2020 Perseverance rover.

Metabolism and Biodegradation of Spacecraft Cleaning Reagents by Strains of Spacecraft-Associated Acinetobacter.

Spacecraft assembly facilities are oligotrophic and low-humidity environments, which are routinely cleaned using alcohol wipes for benchtops and spacecraft materials, and alkaline detergents for floors. Despite these cleaning protocols, spacecraft assembly facilities possess a persistent, diverse, dynamic, and low abundant core microbiome, where the Acinetobacter are among the dominant members of the community. In this report, we show that several spacecraft-associated Acinetobacter metabolize or biodegrade the spacecraft cleaning reagents of ethanol (ethyl alcohol), 2-propanol (isopropyl alcohol), and Kleenol 30 (floor detergent) under ultraminimal conditions. Using cultivation and stable isotope labeling studies, we show that ethanol is a sole carbon source when cultivating in 0.2 × M9 minimal medium containing 26 µM Fe(NH4)2(SO4)2. Although cultures expectedly did not grow solely on 2-propanol, cultivations on mixtures of ethanol and 2-propanol exhibited enhanced plate counts at mole ratios of ≤0.50. In support, enzymology experiments on cellular extracts were consistent with oxidation of ethanol and 2-propanol by a membrane-bound alcohol dehydrogenase. In the presence of Kleenol 30, untargeted metabolite profiling on ultraminimal cultures of Acinetobacter radioresistens 50v1 indicated (1) biodegradation of Kleenol 30 into products including ethylene glycols, (2) the potential metabolism of decanoate (formed during incubation of Kleenol 30 in 0.2 × M9), and (3) decreases in the abundances of several hydroxy- and ketoacids in the extracellular metabolome. In ultraminimal medium (when using ethanol as a sole carbon source), A. radioresistens 50v1 also exhibits a remarkable survival against hydrogen peroxide (∼1.5-log loss, ∼108 colony forming units (cfu)/mL, 10 mM H2O2), indicating a considerable tolerance toward oxidative stress under nutrient-restricted conditions. Together, these results suggest that the spacecraft cleaning reagents may (1) serve as nutrient sources under oligotrophic conditions and (2) sustain extremotolerances against the oxidative stresses associated with low-humidity environments. In perspective, this study provides a plausible biochemical rationale to the observed microbial ecology dynamics of spacecraft-associated environments.

A Systematic Review on Effect of Electronic Media on Diet, Exercise, and Sexual Activity among Adolescents.

CONTEXT: Electronic media has become a part of day-to-day life for all, and particularly more so for children and adolescents. Exposure to electronic media may be beneficial as well as harmful. AIM: The aim of the study is to systematically synthesize existing published and non-published empirical evidence on the effect of exposure to electronic media on diet, exercise, and sexual activity. METHODOLOGY: Two reviewers independently searched online databases such as MEDLINE, CENTRAL, and EMBASE. We applied no language, date, or publication restrictions. SELECTION CRITERIA: We included randomized control trials that assessed the effect of exposure of electronic media on diet, exercise, and sexual activity in participants between 5 and 19 years. STUDY SELECTION DATA EXTRACTION: Two reviewers independently screened studies identified in electronic search and independently extracted data and assessed the risk of bias of included studies. DATA ANALYSIS: We had planned to use the risk ratio or odds ratio for dichotomous data, and mean difference (MD) or standardized MD for continuous data. However, as included studied differed in types of intervention and reporting of outcomes, we did not undertake meta-analysis. MAIN RESULTS: All included trials were parallel randomized controlled trials except for one that was a crossover trial. Eight studies reported the effect of electronic media on diet and exercise, two on diet, two on exercise, and one on sexual activity. Quality of evidence was rated as "very low" for all outcomes due to too little information or too few data to be able to reach to any conclusions. CONCLUSIONS: There is a little body of evidence that limits conclusions. We need to comprehend as to how to swap undesirable effects of electronic media and make it more desirable. REGISTRATION OF SYSTEMATIC REVIEW: This systematic review has been registered at PROSPERO International prospective register of systematic reviews (Registration number: PROSPERO 2018 CRD42018086935) available at https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=86935.

A Systematic Review on Effect of Electronic Media among Children and Adolescents on Substance Abuse.

BACKGROUND: Substance abuse is one of the most significant global public health issues among youths. Electronic media has become a part of day-to-day life for all. This systematic review is undertaken to comprehensively explore the effect of electronic media on substance abuse among children and adolescents. METHODOLOGY: Two review authors independently searched various electronic databases and other sources. SELECTION CRITERIA: Randomized control trials that assessed the effect of exposure of electronic media (defined as television, internet, gaming, mobile phones/phones, and radio) among participants in the age range of 5-19 years on substance abuse were included in the review. DATA COLLECTION AND ANALYSIS: Two reviewers independently extracted data. We used an approach proposed by the Cochrane Collaboration. We used GRADE profiler to assess the overall quality of the evidence. MAIN RESULTS: We retrieved 6003 studies and found 15 studies that fulfilled our inclusion criteria. Since included studies differed in the type of intervention and reporting of outcomes, we did not undertake meta-analysis and choose to describe studies narratively. Quality of evidence was rated as "very low" due to too little information or too few data to be able to reach any conclusions. AUTHORS' CONCLUSIONS: Clinicians, policymakers, and educators to partner with caregivers and youth to support electronic media use that promotes positive outcome in these areas. REGISTRATION OF SYSTEMATIC REVIEW: This systematic review has been registered at PROSPERO International prospective register of systematic reviews (Registration number: PROSPERO 2018 CRD42018086935) available at https://www.crd.york.ac.uk/prospero/display_record.php?RecordID = 86935.

Functional Metagenomics of Spacecraft Assembly Cleanrooms: Presence of Virulence Factors Associated with Human Pathogens.

Strict planetary protection practices are implemented during spacecraft assembly to prevent inadvertent transfer of earth microorganisms to other planetary bodies. Therefore, spacecraft are assembled in cleanrooms, which undergo strict cleaning and decontamination procedures to reduce total microbial bioburden. We wanted to evaluate if these practices selectively favor survival and growth of hardy microorganisms, such as pathogens. Three geographically distinct cleanrooms were sampled during the assembly of three NASA spacecraft: The Lockheed Martin Aeronautics' Multiple Testing Facility during DAWN, the Kennedy Space Center's Payload Hazardous Servicing Facility (KSC-PHSF) during Phoenix, and the Jet Propulsion Laboratory's Spacecraft Assembly Facility during Mars Science Laboratory. Sample sets were collected from the KSC-PHSF cleanroom at three time points: before arrival of the Phoenix spacecraft, during the assembly and testing of the Phoenix spacecraft, and after removal of the spacecraft from the KSC-PHSF facility. All samples were subjected to metagenomic shotgun sequencing on an Illumina HiSeq 2500 platform. Strict decontamination procedures had a greater impact on microbial communities than sampling location Samples collected during spacecraft assembly were dominated by Acinetobacter spp. We found pathogens and potential virulence factors, which determine pathogenicity in all the samples tested during this study. Though the relative abundance of pathogens was lowest during the Phoenix assembly, potential virulence factors were higher during assembly compared to before and after assembly, indicating a survival advantage. Decreased phylogenetic and pathogenic diversity indicates that decontamination and preventative measures were effective against the majority of microorganisms and well implemented, however, pathogen abundance still increased over time. Four potential pathogens, Acinetobacter baumannii, Acinetobacter lwoffii, Escherichia coli and Legionella pneumophila, and their corresponding virulence factors were present in all cleanroom samples. This is the first functional metagenomics study describing presence of pathogens and their corresponding virulence factors in cleanroom environments. The results of this study should be considered for microbial monitoring of enclosed environments such as schools, homes, hospitals and more isolated habitation such the International Space Station and future manned missions to Mars.