Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “Environmental microbiology”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 343 records · Page 19

Musing over Microbes in Microgravity: Microbial Physiology Flight Experiment

New York City, the most populated city in the United States, is home to over 8 million humans. This means over 26,000 people per square mile! Imagine, though, what the view would be if you peeked into the world of microscopic organisms. Scientists estimate that a gram of soil may contain up to 1 billion of these microbes, which is as much as the entire human population of China! Scientists also know that the world of microbes is incredibly diverse-possibly 10,000 different species in one gram of soil - more than all the different types of mammals in the world. Microbes fill every niche in the world - from 20 miles below the Earth's surface to 20 miles above, and at temperatures from less than -20 C to hotter than water's boiling point. These organisms are ubiquitous because they can adapt quickly to changing environments, an effective strategy for survival. Although we may not realize it, microbes impact every aspect of our lives. Bacteria and fungi help us break down the food in our bodies, and they help clean the air and water around us. They can also cause the dark, filmy buildup on the shower curtain as well as, more seriously, illness and disease. Since humans and microbes share space on Earth, we can benefit tremendously from a better understanding of the workings and physiology of the microbes. This insight can help prevent any harmful effects on humans, on Earth and in space, as well as reap the benefits they provide. Space flight is a unique environment to study how microbes adapt to changing environmental conditions. To advance ground-based research in the field of microbiology, this STS-107 experiment will investigate how microgravity affects bacteria and fungi. Of particular interest are the growth rates and how they respond to certain antimicrobial substances that will be tested; the same tests will be conducted on Earth at the same times. Comparing the results obtained in flight to those on Earth, we will be able to examine how microgravity induces physiological changes in the microbes.

Schweickart, Randolph↗

ATP as a biomarker of viable microorganisms in clean-room facilities

A new firefly luciferase bioluminescence assay method that differentiates free extracellular ATP (dead cells, etc.) from intracellular ATP (viable microbes) was used to determine the viable microbial cleanliness of various clean-room facilities. For comparison, samples were taken from both clean-rooms, where the air was filtered to remove particles >0.5 microm, and ordinary rooms with unfiltered air. The intracellular ATP was determined after enzymatically degrading the sample's free ATP. Also for comparison, cultivable microbial populations were counted on nutrient-rich trypticase soy agar (TSA) plates. Both the cultivable and ATP-based determinations indicate that the microbial burden was lower in clean-room facilities than in ordinary rooms. However, there was no direct correlation between the two sets of measurements because the two assays measured very different populations. A large fraction of the samples yielded no colony formers on TSA, but were positive for intracellular ATP. Subsequently, genomic DNA was isolated directly from selected samples and 16S rDNA fragments were cloned and sequenced, identifying nearest neighbors, many of which are known to be noncultivable in the media employed. It was concluded that viable microbial contamination can be reliably monitored by measurement of intracellular ATP, and that this method may be considered superior to cultivable colony counts due to its speed and its ability to report the presence of viable but noncultivable organisms. When the detection of nonviable microbes is of interest, the ATP assay can be supplemented with DNA analysis.

NASA Discipline Environmental Health↗

Ames Life Science Data Archive: Translational Rodent Research at Ames

The Life Science Data Archive (LSDA) office at Ames is responsible for collecting, curating, distributing and maintaining information pertaining to animal and plant experiments conducted in low earth orbit aboard various space vehicles from 1965 to present. The LSDA will soon be archiving data and tissues samples collected on the next generation of commercial vehicles; e.g., SpaceX & Cygnus Commercial Cargo Craft. To date over 375 rodent flight experiments with translational application have been archived by the Ames LSDA office. This knowledge base of fundamental research can be used to understand mechanisms that affect higher organisms in microgravity and help define additional research whose results could lead the way to closing gaps identified by the Human Research Program (HRP). This poster will highlight Ames contribution to the existing knowledge base and how the LSDA can be a resource to help answer the questions surrounding human health in long duration space exploration. In addition, it will illustrate how this body of knowledge was utilized to further our understanding of how space flight affects the human system and the ability to develop countermeasures that negate the deleterious effects of space flight. The Ames Life Sciences Data Archive (ALSDA) includes current descriptions of over 700 experiments conducted aboard the Shuttle, International Space Station (ISS), NASA/MIR, Bion/Cosmos, Gemini, Biosatellites, Apollo, Skylab, Russian Foton, and ground bed rest studies. Research areas cover Behavior and Performance, Bone and Calcium Physiology, Cardiovascular Physiology, Cell and Molecular Biology, Chronobiology, Developmental Biology, Endocrinology, Environmental Monitoring, Gastrointestinal Physiology, Hematology, Immunology, Life Support System, Metabolism and Nutrition, Microbiology, Muscle Physiology, Neurophysiology, Pharmacology, Plant Biology, Pulmonary Physiology, Radiation Biology, Renal, Fluid and Electrolyte Physiology, and Toxicology. These experiment descriptions and data can be accessed online via the public LSDA website (http://lsda.jsc.nasa.gov) and information can be requested via the Data Request form at http://lsda.jsc.nasa.gov/common/dataRequest/dataRequest.aspx or by contacting the ALSDA Office at: Alison.J.French@nasa.gov

Life Sciences↗

Microbiological concerns and methodological approaches related to bacterial water quality in spaceflight

A number of microbiological issues are of critical importance to crew health and system performance in spacecraft water systems. This presentation reviews an army of these concerns which include factors that influence water treatment and disinfection in spaceflight such as biofilm formation and the physiological responses of bacteria in clean water systems. Factors associated with spaceflight like aerosol formation under conditions of microgravity are also discussed within the context of airborne infections such as Legionellosis. Finally, a spectrum of analytical approaches is reviewed to provide an evaluation of methodological alternatives that have been suggested or used to detect microorganisms of interest in water systems. These range from classical approaches employing colony formation on specific microbiological growth media to direct (i.e. microscopic) and indirect (e.g. electrochemical) methods as well as the use of molecular approaches and gene probes. These techniques are critically evaluated for their potential utility in determining microbiological water quality through the detection of microorganisms under the influence of ambient environmental stress inherent in spaceflight water systems.

Pyle, Barry H.↗

Development of the Space Station Freedom Environmental Health System

The Environmental Health System (EHS), a subsystem of the Space Station Freedom (SSF) Crew Health Care System, was established to ensure that crewmembers will have a safe and healthy environment in which to live and work. EHS is comprised of six subsystems: Microbiology, Toxicology, Water Quality, Radiological Health, Vibroacoustics, and Barothermal Physiology. Each subsystem contributes to the overall functions of the EHS including environmental planning, environmental monitoring, environmental monitoring, environmental health assessments, and operations support. The EHS will provide hardware for monitoring the air, water, and internal surfaces of Freedom, including capabilities for inflight sample collection, processing, and analysis. The closed environment of SSF, and its dependence on recycled air and water, will necessitate a reliable monitoring system to alert crewmembers if contamination levels exceed the maximum allowable limits established to ensure crew health and safety. This paper describes the functions and hardware design status of the EHS.

Richard, Elizabeth E.↗

Microorganisms, climate change, and the Sustainable Development Goals: progress and challenges

The forthcoming UN summit marks the halfway point to 2030 and presents an important milestone in global efforts to address various challenges, including those related to climate change and environmental preservation. The UN SDGs include several related to microorganisms and climate change. Importantly, microbiology research is key to understanding and mitigating climate change, and in maintaining the health of terrestrial and aquatic ecosystems (SDGs 13, 14 and 15).

59 BASIC BIOLOGICAL SCIENCES↗

Improvement of eukaryotic protein predictions from soil metagenomes

During the last decades, metagenomics has highlighted the diversity of microorganisms from environmental or host-associated samples. Most metagenomics public repositories use annotation pipelines tailored for prokaryotes regardless of the taxonomic origin of contigs. Consequently, eukaryotic contigs with intrinsically different gene features, are not optimally annotated. Using a bioinformatics pipeline, we have filtered 7.9 billion contigs from 6,872 soil metagenomes in the JGI’s IMG/M database to identify eukaryotic contigs. We have re-annotated genes using eukaryote-tailored methods, yielding 8 million eukaryotic proteins and over 300,000 orphan proteins lacking homology in public databases. Comparing the gene predictions we made with initial JGI ones on the same contigs, we confirmed our pipeline improves eukaryotic proteins completeness and contiguity in soil metagenomes. The improved quality of eukaryotic proteins combined with a more comprehensive assignment method yielded more reliable taxonomic annotation. This dataset of eukaryotic soil proteins with improved completeness, quality and taxonomic annotation reliability is of interest for any scientist aiming at studying the composition, biological functions and gene flux in soil communities involving eukaryotes.

54 ENVIRONMENTAL SCIENCES↗

STS-3 medical report

The medical operations report for STS-3, which includes a review of the health of the crew before, during, and immediately after the third Shuttle orbital flight is presented. Areas reviewed include: health evaluation, medical debriefing of crewmembers, health stabilization program, medical training, medical 'kit' carried in flight, tests and countermeasures for space motion sickness, cardiovascular profile, biochemistry and endocrinology results, hematology and immunology analyses, medical microbiology, food and nutrition, potable water, shuttle toxicology, radiological health, and cabin acoustic noise. Environmental effects of shuttle launch and landing medical information management, and management, planning, and implementation of the medical program are also dicussed.

Pool, S. L.↗

USSR Space Life Sciences Digest, issue 4

The fourth issue of NASA's USSR Space Life Science Digest includes abstracts for 42 Soviet periodical articles in 20 areas of aerospace medicine and space biology and published in Russian during the last third of 1985. Selected articles are illustrated with figures and tables from the original. In addition, translated introductions and tables of contents for 17 Russian books on 12 topics related to NASA's life science concerns are presented. Areas covered are: adaptation, biological rhythms, biospherics, body fluids, botany, cardiovascular and respiratory systems, cytology, developmental biology, endocrinology, exobiology, habitability and environmental effects, health and medical treatment, hematology, histology, human performance, immunology, mathematical modeling, metabolism, microbiology, musculoskeletal system, neurophysiology, nutrition, perception, personnel selection, psychology, and radiobiology. Two book reviews translated from the Russian are included and lists of additional relevant titles available in English with pertinent ordering information are given.

Hooke, L. R.↗

Colonization by Cladosporium spp. of painted metal surfaces associated with heating and air conditioning systems

Cladosporium cladosporioides and C. hebarum colonized painted metal surfaces of covering panels and register vents of heating, air conditioning and ventilation systems. Hyphae penetrated the paint film and developed characteristic conidiophores and conidia. The colonies were tightly appressed to the metal surface and conidia were not readily detectable via standard air sampling procedures.

NASA Program Environmental Health↗

Sensitive detection of Escherichia coli O157:H7 in food and water by immunomagnetic separation and solid-phase laser cytometry

Rapid, direct methods are needed to assess active bacterial populations in water and foods. Our objective was to determine the efficiency of bacterial detection by immunomagnetic separation (IMS) and the compatibility of IMS with cyanoditolyl tetrazolium chloride (CTC) incubation to determine respiratory activity, using the pathogen Escherichia coli O157:H7. Counterstaining with a specific fluorescein-conjugated anti-O157 antibody (FAb) following CTC incubation was used to allow confirmation and visualization of bacteria by epifluorescence microscopy. Broth-grown E. coli O157:H7 was used to inoculate fresh ground beef (<17% fat), sterile 0.1% peptone, or water. Inoculated meat was diluted and homogenized in a stomacher and then incubated with paramagnetic beads coated with anti-O157 specific antibody. After IMS, cells with magnetic beads attached were stained with CTC and then an anti-O157 antibody-fluorescein isothiocyanate conjugate and filtered for microscopic enumeration or solid-phase laser cytometry. Enumeration by laser scanning permitted detection of ca. 10 CFU/g of ground beef or <10 CFU/ml of liquid sample. With inoculated meat, the regression results for log-transformed respiring FAb-positive counts of cells recovered on beads versus sorbitol-negative plate counts in the inoculum were as follows: intercept = 1.06, slope = 0.89, and r2 = 0. 95 (n = 13). The corresponding results for inoculated peptone were as follows: intercept = 0.67, slope = 0.88, and r2 = 0.98 (n = 24). Recovery of target bacteria on beads by the IMS-CTC-FAb method, compared with recovery by sorbitol MacConkey agar plating, yielded greater numbers (beef, 6.0 times; peptone, 3.0 times; water, 2.4 times). Thus, within 5 to 7 h, the IMS-CTC-FAb method detected greater numbers of E. coli O157 cells than were detected by plating. The results show that the IMS-CTC-FAb technique with enumeration by either fluorescence microscopy or solid-phase laser scanning cytometry gave results that compared favorably with plating following IMS.

Non-NASA Center↗

AMEBoP: Additive Manufacturing Enabled Biofilm Prevention

Objective: Leverage additive manufacturing to fortify Environmental Control and Life Support Systems (ECLSS) manifolds and other vulnerable components against biofilm growth during dormancy by eliminating dead legs to reduce total stagnate fluid volume and available nutrients and by printing from inherently biocidal materials.

ECLSS↗

AMEBoP: Additive Manufacturing Enabled Biofilm Prevention

Leverage additive manufacturing to fortify ECLSS (Environmental Control and Life Support Systems) manifolds and other vulnerable components against biofilm growth during dormancy. This project aims to improve dormancy tolerance by eliminating dead legs to reduce stagnate fluid volume and to limit available nutrients, and by printing from inherently biocidal materials.

ECLSS↗

Legacy of Environmental Research During the Space Shuttle Program

The Space Shuttle Program provided many opportunities to study the role of spaceflight on human life for over the last 30 years and represents the longest and largest U.S. human spaceflight program. Risks to crewmembers were included in the research areas of nutrition, microbiology, toxicology, radiation, and sleep quality. To better understand the Shuttle environment, Crew Health Care System was developed. As part of this system, the Environmental Health Subsystem was developed to monitor the atmosphere for gaseous contaminants and microbial contamination levels and to monitor water quality and radiation. This program expended a great deal of effort in studying and mitigating risks related to contaminations due to food, water, air, surfaces, crewmembers, and payloads including those with animals. As the Shuttle had limited stowage space and food selection, the development of nutritional requirements for crewmembers was imperative. As the Shuttle was a reusable vehicle, microbial contamination was of great concern. The development of monitoring instruments that could withstand the space environment took several years and many variations to come up with a suitable instrument. Research with space radiation provided an improved understanding of the various sources of ionizing radiation and the development of monitoring instrumentation for space weather and the human exposure within the orbiter's cabin. Space toxicology matured to include the management of offgassing products that could pollute the crewmembers air quality. The Shuttle Program implemented a 5-level toxicity rating system and developed new monitoring instrumentation to detect toxic compounds. The environment of space caused circadian desynchrony, sleep deficiency, and fatigue leading to much research and major emphasis on countermeasures. Outcomes of the research in these areas were countermeasures, operational protocols, and hardware. Learning Objectives: This symposium will provide an overview of the major environmental lessons learned and the development of countermeasures, monitoring hardware, and procedures.

Lane, Helen W.↗