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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.

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At least 433 records · Page 24

Pilot Residential Deep Energy Retrofits and the PNNL Lab Homes

This report summarizes research investigating the technical and economic feasibility of several pilot deep energy retrofits, or retrofits that save 30% to 50% or more on a whole-house basis while increasing comfort, durability, combustion safety, and indoor air quality. The work is being conducted for the U.S. Department of Energy Building Technologies Program as part of the Building America Program. As part of the overall program, Pacific Northwest National Laboratory (PNNL) researchers are collecting and analyzing a comprehensive dataset that describes pre- and post-retrofit energy consumption, retrofit measure cost, health and comfort impacts, and other pertinent information for each home participating in the study. The research and data collection protocol includes recruitment of candidate residences, a thorough test-in audit, home energy modeling, and generation of retrofit measure recommendations, implementation of the measures, test-out, and continued evaluation. On some homes, more detailed data will be collected to disaggregate energy-consumption information. This multi-year effort began in October 2010. To date, the PNNL team has performed test-in audits on 51 homes in the marine, cold, and hot-humid climate zones, and completed 3 retrofits in Texas, 10 in Florida, and 2 in the Pacific Northwest. Two of the retrofits are anticipated to save 50% or more in energy bills and the others - savings are in the 30% to 40% range. Fourteen other retrofits are under way in the three climate zones. Metering equipment has been installed in seven of these retrofits - three in Texas, three in Florida, and one in the Pacific Northwest. This report is an interim update, providing information on the research protocol and status of the PNNL deep energy retrofit project as of December, 2011. The report also presents key findings and lessons learned, based on the body of work to date. In addition, the report summarizes the status of the PNNL Lab Homes that are new manufactured homes procured with minimal energy-efficiency specifications typical of existing homes in the region, and sited on the PNNL campus. The Lab Homes serve as a flexible test facility (the first of its kind in the Pacific Northwest) to rapidly evaluate energy-efficient and grid-smart technologies that are applicable to residential construction.

54 ENVIRONMENTAL SCIENCES↗

Preparation of Aluminum Oxide Films Under Water Exposure – Preliminary Report on 1100 Series Alloys

This report describes laboratory experiments performed to produce oxyhydroxide (oxide) films on aluminum 1100 series alloy substrates at various water/temperature conditions. The aluminum alloys selected in this program are types used on aluminum-clad research reactor fuel, and the water/temperature conditions are selected to produce film structures that would be prototypic to those formed on the fuel as a result of reactor exposure and post-discharge water and/or dry storage exposure. The experimental set-up and results to characterize the oxide morphology, thickness, structure, and chemical composition are reported. The results from this work will be compared to oxide characterizations of fuel cladding alloys that have been exposed to actual reactor and post-discharge service conditions. The aim is to develop a laboratory protocol to produce specimens for further studies for response under drying and radiation conditions. The work in this report is interim results and preliminary information prepared under Task 6, Milestone 6.1 in TTQAP SRNL-RP-2018-00610 as part of the action plan described in Ref. [1]. Additional experimental milestones are in progress and will be reported upon completion.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

Monitoring, Reporting, and Verification Considerations for Carbon Dioxide Removal

The project investigates Measurement, Reporting, and Verification (MRV) methods for Enhanced Weathering and Marine Carbon Dioxide Removal (mCDR) technologies. Enhanced Weathering accelerates natural mineral processes to capture CO2, while mCDR leverages oceanic processes for carbon sequestration. The study focuses on developing standardized MRV protocols, assessing environmental impacts, and evaluating the scalability and economic feasibility of these carbon sequestration methods. The goal is to ensure reliable and transparent data for validating and improving CO2 removal technologies.

Priyadarshini↗

Optimization of electroporation method and promoter evaluation for type-1 methanotroph, Methylotuvimicrobium alcaliphilum

Methanotrophic bacteria are promising hosts for methane bioconversion to biochemicals or bioproducts. However, due to limitations associated with long genetic manipulation timelines and, lack of choice in genetic tools required for strain engineering, methanotrophs are currently not employed for bioconversion technologies. In this study, a rapid and reproducible electroporation protocol is developed for type 1 methanotroph, Methylotuvimicrobium alcaliphilum using common laboratory solutions, analyzing optimal electroshock voltages and post-shock cell recovery time. Successful reproducibility of the developed method was achieved when different replicative plasmids were assessed on lab adapted vs. wild-type M. alcaliphilum strains (DASS vs. DSM19304). Overall, a ∼ 3-fold decrease in time is reported with use of electroporation protocol developed here, compared to conjugation, which is the traditionally employed approach. Additionally, an inducible (3-methyl benzoate) and a constitutive (sucrose phosphate synthase) promoter is characterized for their strength in driving gene expression.

59 BASIC BIOLOGICAL SCIENCES↗

Carrier-assisted One-pot Sample Preparation for Targeted Proteomics Analysis of Small Numbers of Human Cells

Protein analysis of small numbers of human cells is primarily achieved by targeted proteomics with antibody-based immunoassays, which have inherent limitations (e.g., low multiplex and unavailability of antibodies for new proteins). Mass spectrometry (MS)-based targeted proteomics has emerged as an alternative because it is antibody-free, high multiplex, and has high specificity and quantitation accuracy. Recent advances in MS instrumentation make MS-based targeted proteomics possible for multiplexed quantification of highly abundant proteins in single cells. However, there is a technical challenge for effective processing of single cells with minimal sample loss for MS analysis. To address this issue, we have recently developed a convenient protein carrier-assisted one-pot sample preparation coupled with liquid chromatography (LC) - selected reaction monitoring (SRM) termed cLC-SRM for targeted proteomics analysis of small numbers of human cells. This method capitalizes on using the combined excessive exogenous protein as a carrier and low-volume one-pot processing to greatly reduce surface adsorption losses as well as high-specificity LC-SRM to effectively address the increased dynamic concentration range due to the addition of exogeneous carrier protein. Its utility has been demonstrated by accurate quantification of most moderately abundant proteins in small numbers of cells (e.g., 10-100 cells) and highly abundant proteins in single cells. The easy-to-implement features and no need for specific devices make this method readily accessible to most proteomics laboratories. In this study, we have provided a detailed protocol for cLC-SRM analysis of small numbers of human cells including cell sorting, cell lysis and digestion, LC-SRM analysis, and data analysis. Further improvements in detection sensitivity and sample throughput are needed towards targeted single-cell proteomics analysis. We anticipate that cLC-SRM will be broadly applied to biomedical research and systems biology with the potential of facilitating precision medicine.

60 APPLIED LIFE SCIENCES↗

Anti-Ultralocality and Plateau Models of Inflation

Anti-ultralocality refers to the growth of spatial gradient terms relative to velocity terms in the coupled Einstein--scalar field equations. It is a characteristic feature of decelerated expansion before the onset of inflation. Previous numerical relativity studies have shown that anti-ultralocality prevents the onset of inflation in models with power-law inflaton potentials. In this paper, we show that models with plateau-shaped inflaton potentials, which are considered to be the simplest way to generate a tensor-to-scalar ratio below current observational upper limits, are especially vulnerable to anti-ultralocality effects. The reasons are the flatness of the plateau and the energy density gap of $\sim 10$ orders of magnitude between the Planck density and the plateau potential energy. To study the problem, we develop a protocol for assessing the viability of inflationary models in general, and we apply it to a plateau potential using a previously validated numerical relativity code. We find that, starting from generic initial conditions, the growth of gradient terms in the Einstein equations relative to non-gradient terms either prevents inflation from lasting for enough $e$-folds or triggers a phase of quantum runaway. We show that the fine-tuning of initial conditions necessary to avoid these issues becomes more severe as the energy scale of inflation is made smaller, disfavoring common approaches for reducing the tensor-to-scalar ratio.

FOS: Physical sciences↗

Medical Support and Findings of the Skylab Program

Specific equipment used in carrying out Skylab medical experiments is outlined and illustrated. Also included are reviews of the techniques, frequency, and protocols of the tests designed to study the long term effects of weightlessness on the human body. In-flight investigations were an evaluation of the cardiovascular system, a study of metabolic activity, investigations in the field of neurophysiology, the determination of changes in body fluids, a precise measurement of total body metabolism, and a study of crew performance by use of a time and motion experiment. Significant data obtained from in-flight and postflight tests are outlined.

Johnston, Richard S.↗

Investigation of wheat coleoptile response to phototropic stimulations

This report provides a summary of the preparations for, and the conduct and post-flight data analysis of, the Spacelab flight investigation FOTRAN, which flew on the IML-1 mission (STS-42) in January, 1992. The investigation was designed to provide data on the responses of wheat seedlings to various blue-light stimuli given while the plants were exposed to orbital microgravity conditions. Before the flight, a number of hypotheses were established which were to be tested by the data from the flight and parallel ground studies. A description of the experiment protocol developed for the mission is provided, and an account of the activities supported during preparations for and support of the flight experiment is given. Details of the methods used to reduce and analyze the data from the flight are outlined.

Heathcote, David G.↗

In Vivo Noninvasive Analysis of Human Forearm Muscle Function and Fatigue: Applications to EVA Operations and Training Maneuvers

Forearm muscle fatigue is one of the major limiting factors affecting endurance during performance of deep-space extravehicular activity (EVA) by crew members. Magnetic resonance (MR) provides in vivo noninvasive analysis of tissue level metabolism and fluid exchange dynamics in exercised forearm muscles through the monitoring of proton magnetic resonance imaging (MRI) and phosphorus magnetic resonance spectroscopy (P-31-MRS) parameter variations. Using a space glove box and EVA simulation protocols, we conducted a preliminary MRS/MRI study in a small group of human test subjects during submaximal exercise and recovery and following exhaustive exercise. In assessing simulated EVA-related muscle fatigue and function, this pilot study revealed substantial changes in the MR image longitudinal relaxation times (T2) as an indicator of specific muscle activation and proton flux as well as changes in spectral phosphocreatine-to-phosphate (PCr/Pi) levels as a function of tissue bioenergetic potential.

Fotedar, L. K.↗

Analysis of proteins involved in biodegradation of crop biomass

The biodegradation of crop biomass for re-use in crop production is part of the bioregenerative life support concept proposed by the National Aeronautics and Space Administration (NASA) for long duration, manned space exploration. The current research was conducted in the laboratory to evaluate the use of electrophoretic analysis as a means of rapidly assaying for constitutive and induced proteins associated with the bacterial degradation of crop residue. The proteins involved in crop biomass biodegradation are either constitutive or induced. As a result, effluent and cultures were examined to investigate the potential of using electrophoretic techniques as a means of monitoring the biodegradation process. Protein concentration for optimum banding patterns was determined using the Bio-Rad Protein Assay kit. Four bacterial soil isolates were obtained from the G.W. Carver research Farm at Tuskegee University and used in the decomposition of components of plant biomass. The culture, WDSt3A was inoculated into 500 mL of either Tryptic Soy Broth or Nutrient Broth. Incubation, with shaking of each flask was for 96 hours at 30 C. The cultures consistently gave unique banding patterns under denaturing protein electrophoresis conditions, The associated extracellular enzymes also yielded characteristic banding patterns over a 14-day period, when native electrophoresis techniques were used to examine effluent from batch culture bioreactors. The current study evaluated sample preparation and staining protocols to determine the ease of use, reproducibility and reliability, as well as the potential for automation.

Crawford, Kamau↗

A Closed Mars Analog Simulation: The Approach of Crew 5 At the Mars Desert Research Station

For twelve days in April 2002 we performed a closed simulation in the Mars Desert Research Station, isolated from other people, as on Mars, while performing systematic surface exploration and life support chores. Email provided our only means of contact; no phone or radio conversations were possible. All mission-related messages were mediated by a remote mission support team. This protocol enabled a systematic and controlled study of crew activities, scheduling, and use of space. The analysis presented here focuses on two questions: Where did the time go-why did people feel rushed and unable to complete their work? How can we measure and model productivity, to compare habitat designs, schedules, roles, and tools? Analysis suggests that a simple scheduling change-having lunch and dinner earlier, plus eliminating afternoon meetings-increased the available productive time by 41%.

Clancey, William J.↗

Automated Static Culture System Cell Module Mixing Protocol and Computational Fluid Dynamics Analysis

This report is a documentation of a fluid dynamic analysis of the proposed Automated Static Culture System (ASCS) cell module mixing protocol. The report consists of a review of some basic fluid dynamics principles appropriate for the mixing of a patch of high oxygen content media into the surrounding media which is initially depleted of oxygen, followed by a computational fluid dynamics (CFD) study of this process for the proposed protocol over a range of the governing parameters. The time histories of oxygen concentration distributions and mechanical shear levels generated are used to characterize the mixing process for different parameter values.

Kleis, Stanley J.↗

Model Checking Failed Conjectures in Theorem Proving: A Case Study

Interactive mechanical theorem proving can provide high assurance of correct design, but it can also be a slow iterative process. Much time is spent determining why a proof of a conjecture is not forthcoming. In some cases, the conjecture is false and in others, the attempted proof is insufficient. In this case study, we use the SAL family of model checkers to generate a concrete counterexample to an unproven conjecture specified in the mechanical theorem prover, PVS. The focus of our case study is the ROBUS Interactive Consistency Protocol. We combine the use of a mechanical theorem prover and a model checker to expose a subtle flaw in the protocol that occurs under a particular scenario of faults and processor states. Uncovering the flaw allows us to mend the protocol and complete its general verification in PVS.

Pike, Lee↗

Microbiological Methodology in Astrobiology

Searching for life in astromaterials to be delivered from the future missions to extraterrestrial bodies is undoubtedly related to studies of the properties and signatures of living microbial cells and microfossils on Earth. As model terrestrial analogs of Martian polar subsurface layers are often regarded the Antarctic glacier and Earth permafrost habitats where alive microbial cells preserved viability for millennia years due to entering the anabiotic state. For the future findings of viable microorganisms in samples from extraterrestrial objects, it is important to use a combined methodology that includes classical microbiological methods, plating onto nutrient media, direct epifluorescence and electron microscopy examinations, detection of the elemental composition of cells, radiolabeling techniques, PCR and FISH methods. Of great importance is to ensure authenticity of microorganisms (if any in studied samples) and to standardize the protocols used to minimize a risk of external contamination. Although the convincing evidence of extraterrestrial microbial life will may come from the discovery of living cells in astromaterials, biomorphs and microfossils must also be regarded as a target in search of life evidence bearing in mind a scenario that alive microorganisms had not be preserved and underwent mineralization. Under the laboratory conditions, processes that accompanied fossilization of cyanobacteria were reconstructed, and artificially produced cyanobacterial stromatolites resembles by their morphological properties those found in natural Earth habitats. Regarding the vital importance of distinguishing between biogenic and abiogenic signatures and between living and fossil microorganisms in analyzed samples, it is worthwhile to use some previously developed approaches based on electron microscopy examinations and analysis of elemental composition of biomorphs in situ and comparison with the analogous data obtained for laboratory microbial cultures and fossilized microorganisms. This communication will be focused on the analysis of our experience in working with ancient microorganisms and fossils and discussion of some issues that are crucial for development of the program for future finding of extraterrestrial life and its evidence.

Abyzov, S. S.↗

Discussion on LDPC Codes and Uplink Coding

This slide presentation reviews the progress that the workgroup on Low-Density Parity-Check (LDPC) for space link coding. The workgroup is tasked with developing and recommending new error correcting codes for near-Earth, Lunar, and deep space applications. Included in the presentation is a summary of the technical progress of the workgroup. Charts that show the LDPC decoder sensitivity to symbol scaling errors are reviewed, as well as a chart showing the performance of several frame synchronizer algorithms compared to that of some good codes and LDPC decoder tests at ESTL. Also reviewed is a study on Coding, Modulation, and Link Protocol (CMLP), and the recommended codes. A design for the Pseudo-Randomizer with LDPC Decoder and CRC is also reviewed. A chart that summarizes the three proposed coding systems is also presented.

uplink↗

Cure Cycle Design Methodology for Fabricating Reactive Resin Matrix Fiber Reinforced Composites: A Protocol for Producing Void-free Quality Laminates

For the fabrication of resin matrix fiber reinforced composite laminates, a workable cure cycle (i.e., temperature and pressure profiles as a function of processing time) is needed and is critical for achieving void-free laminate consolidation. Design of such a cure cycle is not trivial, especially when dealing with reactive matrix resins. An empirical "trial and error" approach has been used as common practice in the composite industry. Such an approach is not only costly, but also ineffective at establishing the optimal processing conditions for a specific resin/fiber composite system. In this report, a rational "processing science" based approach is established, and a universal cure cycle design protocol is proposed. Following this protocol, a workable and optimal cure cycle can be readily and rationally designed for most reactive resin systems in a cost effective way. This design protocol has been validated through experimental studies of several reactive polyimide composites for a wide spectrum of usage that has been documented in the previous publications.

Hou, Tan-Hung↗

Venus High Temperature Atmospheric Dropsonde and Extreme-Environment Seismometer (HADES)

The atmospheric composition and geologic structure of Venus have been identified by the US National Research Council's Decadal Survey for Planetary Science as priority targets for scientific exploration, however the high temperature and pressure at the surface, along with the highly corrosive chemistry of the Venus atmosphere, present significant obstacles to spacecraft design that have severely limited past and proposed landed missions. Following the methodology of the NASA Innovative Advanced Concepts (NIAC) proposal regime and the Collaborative Modeling and Parametric Assessment of Space Systems (COMPASS) design protocol, this paper presents a conceptual study and initial feasibility analysis for a Discovery-class Venus lander capable of an extended-duration mission at ambient temperature and pressure, incorporating emerging technologies within the field of high temperature electronics in combination with novel configurations of proven, high Technology Readiness Level (TRL) systems. Radioisotope Thermal Power (RTG) systems and silicon carbide (SiC) communications and data handling are examined in detail, and various high-temperature instruments are proposed, including a seismometer and an advanced photodiode imager. The study combines this technological analysis with proposals for a descent instrument package and a relay orbiter to demonstrate the viability of an integrated atmospheric and in-situ geologic exploratory mission that differs from previous proposals by greatly reducing the mass, power requirements, and cost, while achieving important scientific goals.

HADES↗

Circadian and Fatigue Effects on the Dynamics of the Pupillary Light Reflex

The pupillary light reflex (PLR) is known to be driven by the photo-entrainment of intrinsically-photosensitive retinal ganglion cells. These ganglion cells are known to have retino-hypothalamic projections to the suprachiasmatic nuclei (SCN), which regulates circadian rhythms, and bilateral retinal projections to the pretectal area, which mediates the PLR (Dacey et al., 2005; Hattar et al., 2002, 2006). The magnitude of the PLR has previously been shown to show circadian variation (Mnch et al., 2012). In this study, we used a constant routine protocol (Mills et al., 1978) to examine circadian and fatigue effects on the dynamics of the PLR. We characterized the PLR (pupil size as a function of time) in response to a square-wave change in the luminance of a white display background, at ten different times over a single circadian cycle. Twelve subjects participated in three daytime baseline runs followed by 7 nighttime runs each separated by an hour (17 23 hours after awakening). The constriction and dilation phases of the PLR waveform were fit separately with a single exponential model (Longtin Milton, 1988; Milton Longtin, 1990) with time constants estimated using a least-squares method. The dilation time constant exhibited a distinct sinusoidal modulation across the circadian cycle and, after 23 hours of wakefulness, decreased on average by 82 ms (paired t-test, p 0.05) relative to baseline (mean: 543 ms). The constriction time constant however, did not show an overall decrease with increased wakefulness. We conclude that the dynamics of the PLR show circadian variation and that, in addition, the briskness of the dilation response to a step-decrease in luminance shows a homeostatic enhancement with increased wakefulness.

human performance↗