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2016-04-05
Technical Paper
2016-01-0396
Prasad S. Mehta, Jennifer Solis Ocampo, Andres Tovar, Prathamesh Chaudhari
Abstract Biologically inspired designs have become evident and proved to be innovative and efficacious throughout the history. This paper introduces a bio-inspired design of protective structures that is lightweight and provides outstanding crashworthiness indicators. In the proposed approach, the protective function of the vehicle structure is matched to the protective capabilities of natural structures such as the fruit peel (e.g., pomelo), abdominal armors (e.g., mantis shrimp), bones (e.g., ribcage and woodpecker skull), as well as other natural protective structures with analogous protective functions include skin and cartilage as well as hooves, antlers, and horns, which are tough, resilient, lightweight, and functionally adapted to withstand repetitive high-energy impact loads. This paper illustrates a methodology to integrate designs inspired by nature, Topology optimization, and conventional modeling tools.
2015-04-14
Technical Paper
2015-01-0354
Ji Wan Kim, Tae Hee Lee
Abstract This study has been conducted to analyze microbial diversity and its community by using a method of NGS(Next generation sequencing) technique that is not rely on cultivation for microbial community in an core evaporator causing odor of car air conditioner. The NGS without any cultivation method of cultivation, has been developed recently and widely. This method is able to research a microorganism that has not been cultivated. Differently with others, it can get a result that is closer to fact, also can acquire more base sequence with larger volume in relatively shorter time. According to bacteria population analysis of 23 samples, It can be known limited number of bacteria can inhabit in Evaporator core, due to small exposure between bacteria and evaporate, as well as its environmental characteristics. With the population analysis, only certain group of it is forming biofilm in proportion.
2014-10-13
Technical Paper
2014-01-2896
Krzysztof Jan Siczek
Abstract Conditions of the bacterial battery have been presented in the article. The models of different design configurations of bacterial battery and its assembly with electric circuit has been elaborated. The obtained values of voltage and currents obtained in such models has been compared with the case of similar circuit using lithium-ion battery and presented in the paper.
2013-04-08
Journal Article
2013-01-1148
George S. Dodos, Fanourios Zannikos
The diesel fuel supply chain faces new challenges associated with microbial contamination symptoms in biodiesel fuel. FAME's (Fatty Acid Methyl Esters) chemical composition along with its hygroscopic nature makes it more “biologically active” and as a result the final blends could be more prone to microbiological contamination. Survey of in-field incidents and facts in the Greek supply chain indicate that biodiesel is more prone to microbial growth. Furthermore, several experimental studies which demonstrate the susceptibility of biodiesel fuel for microbial growth have been conducted in the laboratory. The influence of FAME has been evaluated as well as the effect of microbial proliferation on the quality of the blend. Different types of biodiesel have been blended with Ultra Low Sulphur Diesel at various concentrations, and the resulting blends were mixed with bottom-water of known viable microbial colonies and stored.
2009-07-12
Technical Paper
2009-01-2398
JMR Apollo Arquiza, Jean B. Hunter
Brine dewatering by evaporation on porous media, and collection of wastewater evaporation condensates rich in organic carbon, both provide favorable environments for microbial growth, such as mold overgrowth of rayon wicks in the AES brine evaporation system, and bacterial biofilms on condensate-wetted surfaces. The mold growth reported on AES wicks by Campbell et al. (2003) has been identified by microscopic and molecular techniques as chiefly Chaetomium spp, most likely C. globosum, with minor occurrence of Penicillium, and other fungal species. Bacteria from the genus Bacillus was also isolated. A stable bacterial consortium dominated by three species was recovered from initially-sterile glass surfaces wetted with sterile Biological Water Processor Effluent Ersatz (Verostko et al., 2004) and exposed to humidified air over a period of one week. The species were identified as Enterobacter aerogenes, Microbacterium foliorum and Pseudomonas putida by 16S rDNA sequencing.
2009-07-12
Technical Paper
2009-01-2421
Michele Birmele, LaShelle McCoy, Monsi Roman, Michael S. Roberts
With the installation of the Water Recovery System (WRS) during mission STS-126 in 2008, the International Space Station (ISS) added the capability to recover clean water for reuse from crewmember urine and atmospheric humidity condensate, including EVA (Extravehicular Activity) wastes. The ability to collect, store and process these waste streams is required to increase potable water recovery and support the ISS crew augmentation planned for 2009. During ground testing of the Urine Processing Assembly (UPA), one of two primary component subsystems that comprise the WRS, significant fouling was repeatedly observed in stored urine pretreated with 0.56% of chromium trioxide and sulfuric acid. During initial observation, presumptive microbiological growth clogged and damaged flight-rated hardware under test as part of a risk-mitigation Flight Experiment (FE).
2009-07-12
Technical Paper
2009-01-2488
Sharon Edney, Michele Birmele, Michael S. Roberts
This report describes ground testing of a commercial-off-the-shelf (COTS) water treatment device for contingency recovery of potable liquid from ersatz human urine to support spaceflight testing. The Forward Osmosis Bag (FOB) is a portable, passive water treatment device utilizing osmotic potential to move water across a layered, ultra-filtration membrane to remove pathogens and reject chemical contaminants. The FOB is capable of rejecting ≥90% of the salts, ≥85% of the Total Oxidizable Carbon (TOC), ≥95% of the Total Nitrogen (TN), and ≥93% of Urea-Nitrogen (BUN) in the ersatz urine while completely removing a mixed bacterial population of >108 cells per milliliter.
2009-07-12
Technical Paper
2009-01-2508
Michele Birmele, LaShelle McCoy, Robert Soler, Michael S. Roberts
This report describes proof-of-concept testing of a commercial-off-the-shelf deep ultraviolet LED for future application as a point-of-use or residual disinfection device for spacecraft potable water systems. The electro-optical performance and disinfection efficacy of a 0.5 mW 265nm UV-C LED (UVTOP, Sensor Electronic Technology, Inc., Columbia, SC) was measured in both static and flow environments against five challenge microorganisms inoculated into potable water at an initial concentration ≥ 108 cells per milliliter. The germicidal irradiation from a single UV-C LED array was sufficient to effect > 4-log kill (> 99.99%) of the challenge bacterial population in < 60 minutes contact time.
2009-07-12
Journal Article
2009-01-2383
Yonghui Ma, Nick Schmitt, Ross Remiker
Humidity control within confined spaces is of great importance for current NASA environmental control systems and future exploration applications. The engineered multifunction surfaces (MFS) developed by ORBITEC is a technology that produces hydrophilic and antimicrobial surface properties on a variety of substrate materials. These properties combined with capillary geometry create the basis for a passive condensing heat exchanger (CHX) for applications in reduced gravity environments, eliminating the need for mechanical separators and particulate-based coatings. The technology may also be used to produce hydrophilic and biocidal surface properties on a range of materials for a variety of applications where bacteria and biofilms proliferate, and surface wetting is beneficial.
2008-10-06
Technical Paper
2008-01-2508
Jürgen Krahl, Axel Munack, Yvonne Ruschel, Olaf Schröder, Jürgen Bünger
The replacement of petrol derived fuels by biogenic fuels from renewable resources has become of worldwide interest and is scientifically investigated for its environmental costs and benefits. Biodiesel has been proven as a suitable alternative to fossil diesel fuel and blends up to 20% biodiesel with common diesel fuel are a strongly pushed policy in the U.S.A. and the EU. To investigate the influence of blends on the emissions and possible health effects, we performed a series of studies with several engines (Euro 0, III and IV) measuring regulated and non-regulated exhaust compounds and determining their mutagenic effects using the Bacterial Reverse Mutation Assay (Ames-Test) according to OECD Guideline 471. Emissions of blends showed an approximate linear dependence on the blend composition, in particular when regulated emissions are considered. However, a negative effect of blends was observed with respect to mutagenicity of the exhaust gas emissions.
2008-06-29
Technical Paper
2008-01-2159
Tony Rector, John Steele, Mark Wilson
The proliferation and growth of microorganisms in the Internal Active Thermal Control System (IATCS) aboard the International Space Station (ISS) has been of significant concern since 2001. Initial testing and assessments of biocides to determine bacterial disinfection capability, material compatibility, stability (rate of oxidative degradation and identification of degradation products), solubility, application methodology, impact on coolant toxicity hazard level, and impact on environmental control and life support systems identified a prioritized list of acceptable biocidal agents including glutaraldehyde, ortho-phthalaldehyde (OPA), and methyl isothiazolone. Glutaraldehyde at greater than 25 ppm was eliminated due to NASA concerns with safety and toxicity and methyl isothiazolone was eliminated from further consideration due to ineffectiveness against biofilms and toxicity at higher concentrations.
2008-06-29
Technical Paper
2008-01-2201
Marc D. Porter, Lorraine M. Siperko, John Nordling, April A. Hazen-Bosveld, Chien-Ju Shih, Robert J. Lipert, James S. Fritz
At present, spacecraft water quality is assessed when samples collected on the International Space Station (ISS) are returned to Earth. Several months, however, may pass between sample collection and analysis, potentially compromising sample integrity by risking degradation. For example, iodine and silver, which are the respective biocides used in the U.S. and Russian spacecraft potable water systems, must be held at levels that prevent bacterial growth, while avoiding adverse effects on crew health. A comparable need exists for the detection of many heavy metals, toxic organic compounds, and microorganisms. Lead, cadmium, and nickel have been found, for instance, in the ISS potable water system at amounts that surpass existent requirements. There have been similar occurrences with hazardous organic compounds like formaldehyde and ethylene glycol. Microorganism counts above acceptable limits have also been reported in a few instances.
2008-06-29
Technical Paper
2008-01-1981
Sherwin Gormly, V. Dean Adams, Eric Marchand, Bailey Cannon
This research is intended to provide contamination and ecosynthesis researchers with an engineering development tool for understanding the productivity of metabolically active low temperature brine habitats as potential sites for bacterial colonization by forward contaminating Earth organisms. The specific extremophile microbial culturing conditions targeted were psychrophilic (low temperature), halophilic (high salt), high ambient sulfur, and anaerobic. These low temperature or freezing point suppressed brine habitats with high ambient sulfur concentrations have been suggested as potential subsurface water resources on both Mars and Europa, and may be common among potentially viable extant water environments in the outer solar system.
2008-06-29
Journal Article
2008-01-1982
Wayne Schubert, Robert A. Beaudet
Bacillus sp. ATCC 29669 was isolated from microbial fallout in clean rooms during the assembly of the Viking Spacecraft missions to Mars, making it a potential contamination concern for outbound space missions. Spores from this bacterial strain were found to be thirty times more resistant to dry heat than B. atrophaeus. Spore inactivation rates under vacuum controlled humidity were faster than rates obtained under ambient humidity. Inactivation rates for these heat resistant spores are important considerations for planetary protection implementation where temperature, time and humidity conditions are used to estimate the effectiveness of dry heat microbial reduction (DHMR) procedures.
2007-07-09
Technical Paper
2007-01-3141
Michael P. Hodges, Daniel Woodard, Michael S. Roberts
Microbial control in spacecraft is currently achieved by environmental control of humidity, forced air filtration, and the use of antimicrobials for surface application (i.e., isopropyl alcohol) and biocidal agents for treatment of potable and technical water supplies (e.g., iodine and iodide or ionic and colloidal silver). Continuous monitoring is required to ensure water quality for shuttle and ISS missions. Water distribution systems for exploration missions on the Crew Exploration Vehicle (CEV) may benefit from a single-application surface-bound antimicrobial coating that limits microbial surface attachment. Consequently, we investigated the use of 3-(trimethoxysilyl) propyldimethyloctadecyl ammonium chloride, a commercially available quaternary aminosilane that bonds permanently to surfaces and inhibits microbial growth. To assess its suitability in spacecraft applications, we previously employed a test method to assess the effectiveness of aminosilane coatings on textiles.
2007-07-09
Technical Paper
2007-01-3142
Michael S. Roberts, Mary E. Hummerick, Sharon L. Edney, Patricia A. Bisbee, Michael R. Callahan, Sandy Loucks,, Karen D. Pickering, John C. Sager
This work describes the microbiological assessment and materials compatibility of a silver-based biocide as an alternative to iodine for the Crew Exploration Vehicle (CEV) and future spacecraft potable water systems. In addition to physical and operational anti-microbial counter-measures, the prevention of microbial growth, biofilm formation, and microbiologically induced corrosion in water distribution and storage systems requires maintenance of a biologically-effective, residual biocide concentration in solution and on the wetted surfaces of the system. Because of the potential for biocide depletion in water distribution systems and the development of acquired biocide resistance within microbial populations, even sterile water with residual biocide may, over time, support the growth and/or proliferation of bacteria that pose a risk to crew health and environmental systems.
2007-07-09
Technical Paper
2007-01-3176
James R. Akse, Delfino Zavala, Richard R. Wheeler, Roger W. Dahl, Thomas W. Williams, DeVon W. Griffin
The on-demand production of Medical Grade Water (MGW) is a critical biomedical requirement for future long-duration exploration missions. Potentially, large volumes of MGW may be needed to treat burn victims, with lesser amounts required to reconstitute pharmacological agents for medical preparations and biological experiments, and to formulate parenteral fluids during medical treatment. Storage of MGW is an untenable means to meet this requirement, as are nominal MGW production methods, which use a complex set of processes to remove chemical contaminants, inactivate all microorganisms, and eliminate endotoxins, a toxin originating from gram-negative bacteria cell walls. An innovative microgravity compatible alternative, using a microwave-based MGW generator, is described in this paper. The MGW generator efficiently couples microwaves to a single-phase flowing stream, resulting in super-autoclave temperatures.
2007-07-09
Technical Paper
2007-01-3268
R. F. Strayer, J. Richards, M. P. Hummerick, J. C. Sager
The effects of volume-reduction via compaction (VR-C) on microbial loads and microbially-produced noxious odors during post-treatment storage were investigated. The Crew Exploration Vehicle (CEV) / Orion simulated food trash compartment wastes (FTCW) consisted of 80% food trash with packaging and 20% wipes. Compaction was compared with a non-compacted control and will provide a baseline for comparison with other treatment technologies. The first study was a timecourse with post-treatment storage durations of 1, 2, 4, and 6 weeks. Key response variables were: O2 consumption and CO2 production from waste biodegradation and microbiological assays consisting of total counts and culturable counts of (a) aerobic and anaerobic bacteria, (b) aerobic and anaerobic spore-forming bacteria, (c) specific bacteria including Pseudomonas aeruginosa, Burkholderia cepacia, and Staphylococcus aureus counts, and (d) molds at run termination.
2007-07-09
Technical Paper
2007-01-3108
James Benardini, Erica Hagerman, Tonia Green, Ronald L. Crawford, Randall Sumner, Kasthuri Venkateswaran
The Internal Active Thermal Control System (IATCS) aboard the International Space Station (ISS) contains an aqueous, alkaline fluid (pH 9.5±0.5) that aids in maintaining a habitable environment for the crew. Because microbes have significant potential to cause disease, adverse effects on astronaut health, and microbe-induced corrosion, the presence of both bacteria and viruses within IATCS fluids is of concern. This study sought to detect and identify viral populations in IATCS samples obtained from the Kennedy Space Center as a first step towards characterizing and understanding potential risks associated with them. Samples were concentrated and viral nucleic acids (NA) extracted providing solutions containing 8.87-22.67 μg NA per mL of heat transfer fluid. After further amplification viral DNA and cDNA were then pooled, fluorescently labeled, and hybridized onto a Combimatrix panvira 12K microarray containing probes for ∼1,000 known human viruses.
2007-07-09
Technical Paper
2007-01-3266
Richard R. Wheeler, Neal M. Hadley, Roger W. Dahl, Thomas W. Williams, Delfino B. Zavala, James R. Akse, John W. Fisher
A Microwave Enhanced Solid Waste Freeze Drying Prototype system has been developed for the treatment of solid waste materials generated during extended manned space missions. The system recovers water initially contained within wastes and stabilizes the residue with respect to microbial growth. Dry waste may then be safely stored or passed on to the next waste treatment process. Operating under vacuum, microwave power provides the energy necessary for sublimation of ice contained within the waste. This water vapor is subsequently collected as relatively pure ice on a Peltier thermoelectric condenser as it travels en route to the vacuum pump. In addition to stabilization via dehydration, microwave enhanced Freeze Drying reduces the microbial population (∼90%) in the waste.
2006-07-17
Technical Paper
2006-01-2078
Takashi Baba, Nobuyasu Yamaguchi, Masao Nasu, Youichi Aibe, Masanori Shinohara
In space utilization, an enormous amount of freshwater for drinking, daily use, hydroponics. is used and recycled in a closed habitat. We have developed culture-independent techniques to analyze microbial cells at the single level, a cell itself, and also community level. By using these methods such as fluorescent vital staining (double staining with carboxyfluorescein diacetate and 4′,6-diamidino-2-phenyl indole), microcolony method and denaturing gradient gel electrophoresis (DGGE), bacterial abundance and their physiological activity in freshwater used in Closed Ecology Experiment Facilities (CEEF) “Mini-Earth” were determined.
2006-07-17
Technical Paper
2006-01-2079
Nobuyasu Yamaguchi, Hiroyasu Nagase, Masao Nasu
The prevention of waterborne outbreaks associated with contaminated water is one of the most important topics in closed habitation. We investigated the ability of a newly designed microfluidic device to determine bacterial numbers in freshwater. A microfluidic device was designed and fabricated by polydimethylsiloxane (size: 50 mm × 24 mm). A fluorescent microscope-based system was used for enumeration of cells flowing rapidly through the microchannel. The numbers of E. coli cells suspended in filtrated sterilized water at a density in the order of 104 - 106 /ml determined by this on-chip flow cytometer were similar with the microscopic counts. The time required for enumeration by on-chip flow cytometer was approximately 10 min per sample. This simple enumeration method will contribute to the technical progress in microbiological quality control of fresh water used in CELSS.
2006-07-17
Technical Paper
2006-01-2256
Eric McLamore, Zhen Huang, Sybil Sharvelle, Kathy Banks
Three replicate aerobic-heterotrophic biotrickling filters were designed to promote the simultaneous biodegradation of graywater and a waste gas containing NH3, H2S and CO2. Upon visual observation of discolored solids, it was originally hypothesized that gas-phase CO2 concentrations were excessive, causing regions of anoxic zones to form within the biotrickling filters. Observed discolored (black) biofilm of this nature is typically assumed to be either lysed bacterial cells or anaerobic regions, implying alteration of operational conditions. Solid (biofilm) samples were collected in the presence and absence of gas-phase wastestream(s) to determine if the gas-phase contaminants were contributing to the solid-phase discoloration. Two sets of experiments (shaker flask and solids characterization) were conduced to determine the nature of the discolored solids. Results indicated that the discolored solids were neither anaerobic bacteria nor lysed cells.
2006-07-17
Technical Paper
2006-01-2159
Michael S. Roberts, Randall M. Sumner, Aaron L. Mills
Airborne and surface microbiological sampling was performed on the pressurized Multi-Purpose Logistics Module “Raffaello” (MPLM-6) that serviced the International Space Station (ISS) on NASA Return to Flight mission ISS LF-1/STS-114. In September of 2005, aerosol samples and surface samples were collected from the MPLM at the Kennedy Space Center prior to locker de-stow and module de-integration. Analyses of the culturable bacterial count from selective and non-selective media showed low microbial densities (>100 CFU per sq m) in the MPLM surface samples collected from air filtration ducts and other hardware surfaces. Isolates identified included diverse representatives of the gram-negative and gram-positive bacteria as well as common airborne fungi. Although aerosol bio-burden samples plated onto non-selective media were below detection limit in microbial density (<1 CFU per 500 L), bacterial and fungal populations were detected in surface swab samples.
2006-07-17
Technical Paper
2006-01-2160
Donald C. Obenhuber, Elizabeth Lester, Pun To Yung, Kasthuri Venkateswaran, Adrian Ponce, Barry Pyle, Monserrate Roman
Bacterial endospores are ubiquitous in terrestrial environments as a result of their ability to persist through environmental extremes of moisture, chemical toxins, pressure, heat and UV radiation. Current studies suggest that Airborne Endospore Bioburden (AEB) may be used as an indicator of spacecraft cleanliness. AEB, as measured in closed environment air sampling under laboratory conditions and in the Environmental Control and Life Support System at Marshall Space Flight Center, has indicated that increased total counts of airborne endospores can be correlated to surface microbial contamination. Advanced detection methods using PDMS sampling techniques, the highly sensitive terbium-dipicolinic acid (Tb3+-DPA) endospore assay, and standard microbial monitoring methods can be used to track trends in the settling of airborne spores.
2006-07-17
Technical Paper
2006-01-2157
Monsi C. Roman, Natalee E. Weir, Mark E. Wilson, Barry H. Pyle
A flex hose assembly containing aqueous coolant from the International Space Station (ISS) Internal Active Thermal Control System (IATCS) consisting of a 2 foot section of Teflon hose and quick disconnects (QDs) and a Special Performance Checkout Unit (SPCU) heat exchanger containing separate channels of IATCS coolant and iodinated water used to cool spacesuits and Extravehicular Mobility Units (EMUs) were returned for destructive analyses on Shuttle return to flight mission STS-114. The original aqueous IATCS coolant used in Node 1, the Laboratory Module, and the Airlock consisted of water, borate (pH buffer), phosphate (corrosion control), and silver sulfate (microbiological control) at a pH of 9.5 ± 0.5.
2006-07-17
Technical Paper
2006-01-2177
Chad D. Paavola, Suzanne L. Chan, Kellen M. Mazzarella, Pamela S. Matusik
Biomolecules exhibit specific binding and high affinity for their ligands. These properties can be exploited to produce sensitive, specific, real-time sensors for analytes that cannot be readily monitored by other methods. Several technologies for environmental monitoring using proteins are currently being developed. We discuss specific challenges to practical application of a family of protein-based sensors derived from bacterial periplasmic binding proteins. We also present recent work to address these challenges.
2006-07-17
Technical Paper
2006-01-2182
Richard R. Wheeler, Neal M. Hadley, Roger W. Dahl, Thomas W. Williams, Frank C. Garmon, James R. Akse, James E. Atwater, John W. Fisher
A Microwave Powered Solid Waste Stabilization and Water Recovery Prototype system has been developed for the treatment of solid waste materials generated during extended manned space missions. The system recovers water initially contained within wastes and stabilizes the residue with respect to microbial growth. Dry waste may then be safely stored or passed on to the next waste treatment process. Using microwave power, water present in the solid waste is selectively and rapidly heated. Liquid phase water flashes to steam and superheats. Hot water and steam formed in the interior of waste particles create an environment that is lethal to bacteria, yeasts, molds, and viruses. Steam contacts exposed surfaces and provides an effective thermal kill of microbes, in a manner similar to that of an autoclave. Volatilized water vapor is recovered by condensation.
2006-04-03
Technical Paper
2006-01-1645
S. A. Mueller, B. R. Kim, J. E. Anderson
Corrosion failures of aluminum air conditioner evaporator cores have been reported in regions where the climate is relatively warm and humid. Microbiologically-influenced corrosion [MIC] has been implicated in these failures. Application of surface-treatment chemicals may inhibit microbiological (bacterial) growth and/or attachment, thereby reducing the potential for MIC. In this study, two laboratory methods were developed to evaluate selected surface-treatment chemicals for their ability to inhibit bacterial growth and reduce bacterial attachment to treated surfaces. Using the developed methods, two controlled-atmosphere brazed aluminum core materials and three surface-treatment chemicals were evaluated. Neither of the untreated core materials was found to inhibit the growth of the bacteria tested.
2005-07-11
Technical Paper
2005-01-2932
David Newcombe, Tara Stuecker, Myron La Duc, Kasthuri Venkateswaran
Previous studies indicated evidence of opportunistic pathogens in samples obtained during missions to the International Space Station (ISS). This study utilized TaqMan quantitative PCR to determine specific gene abundance in potable and non-potable ISS waters. Probe and primer sets specific to the small subunit rRNA genes were designed and used to elucidate overall bacterial rRNA gene numbers. In addition, primer-probe sets specific for Burkholderia cepacia and Stenotrophomonas maltophilia were optimized and genes of these two opportunistic pathogens quantified in the pre- and post-flight drinking water as well as coolant waters. This Q-PCR approach supports findings of previous culture-based studies however; the culture based studies may have underestimated the microbial burden of ISS drinking water.
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