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DOE OSTI2020

Genetic circuit design automation for yeast

Cells can be programmed to monitor and react to their environment using genetic circuits. Design automation software maps a desired circuit function to a DNA sequence, a process that requires units of gene regulation (gates) that are simple to connect and behave predictably. This poses a challenge for eukaryotes due to their complex mechanisms of transcription and translation. To this end, we have developed gates for yeast (Saccharomyces cerevisiae) that are connected using RNA polymerase flux as the signal carrier and are insulated from each other and host regulation. They are based on minimal constitutive promoters (~120 base pairs), for which rules are developed to insert operators for DNA-binding proteins. Using this approach, in this work we constructed nine NOT/NOR gates with nearly identical response functions and 400-fold dynamic range. In circuits, they are transcriptionally insulated from each other by placing ribozymes downstream of terminators to block nuclear export of messenger RNAs resulting from RNA polymerase readthrough. Based on these gates, Cello 2.0 was used to build circuits with up to 11 regulatory proteins. A simple dynamic model predicts the circuit response over days. Genetic circuit design automation for eukaryotes simplifies the construction of regulatory networks as part of cellular engineering projects, whether it be to stage processes during bioproduction, serve as environmental sentinels or guide living therapeutics.

59 BASIC BIOLOGICAL SCIENCES↗

DOE OSTI2020

Unveiling the mechanisms of lithium dendrite suppression by cationic polymer film induced solid–electrolyte interphase modification

It is crucial to suppress lithium dendrite formation in lithium metal batteries. Formation of a good solid–electrolyte interphase (SEI) has been considered to be effective in limiting lithium dendrite growth. However, how the SEI may be modified during lithium deposition is hard to resolve due to challenges in in situ investigation of the SEI with fine details. Here, we report an in situ study that uncovers the lithium dendrite suppression mechanism arising from SEI modification by a poly(diallyldimethylammonium chloride) (PDDA) cationic polymer film, using electrochemical liquid cell transmission electron microscopy (TEM). Lithium nanogranules are obtained in the presence of the polymer film. Chemical mapping of the deposits provides remarkable details of the SEI on individual nanogranules. It shows that lithium fluorides are uniformly distributed within the inner SEI layer of individual lithium nanogranules, arising from the instantaneous reaction of the deposited lithium with PF 6 – ions accumulated by the cationic polymer film, and thus the dendritic growth of lithium is prohibited. The ability to directly measure SEI chemistry at the nanoscale down to the individual nanograins in situ and unveil its correlation with the lithium deposition behavior opens future opportunities to explore unsolved mechanisms in batteries.

25 ENERGY STORAGE↗

DOE OSTI2026

Cis-regulatory evolution shapes facial diversity in birds and mammals

Birds and mammals exhibit extraordinary facial diversity, reflecting adaptations to distinct ecological niches and feeding strategies. While core face-building developmental programs are conserved and orchestrated by interactions between ectodermal organizers and the underlying mesenchyme, mechanisms driving facial shape variation remain poorly understood. Here, we integrate single-cell transcriptomic and chromatin accessibility profiling of mouse and chicken developing face to construct a comparative regulatory map. Although both ectodermal and mesenchymal populations display distinct regulatory features in each species, the mesenchyme exhibits markedly greater divergence, pointing to its central role in shaping facial morphology. We further reveal unexpected molecular complexity in the main face-shaping organizer, including a mouse-specific Shh/Wnt5a expression domain. At key morphogen loci (Bmp4, Fgf8, and Wnt5a), conserved and lineage-specific enhancers exhibit spatially restricted activity patterns that mirror divergent signaling domains. These findings demonstrate how cis-regulatory evolution modulates conserved developmental programs to generate morphological novelty, providing a valuable resource for studying vertebrate facial evolution.

Kyomen, Stella [Max Planck Institute for Evolution↗

DOE OSTI2021

The Impact of Sintering Atmosphere and Temperature on the Phase Evolution of High Surface Area LSCF Prepared by In Situ Carbon Templating

The thermochemical stability of lanthanum strontium cobalt ferrite (LSCF) processed between 1000 °C–1200 °C via the in situ carbon templating method was studied. This method generates high surface area ceramics at traditional solid oxide fuel cell (SOFC) sintering temperatures by generating a carbon template in situ and subsequently removing the template by oxidation at 700 °C. Argon processed samples produced an amorphous carbon template, whereas nitrogen tended to form graphitic carbon. Prior to the oxidation step, nitrogen samples comprised larger La 2 O 3 crystallites (22–40 nm) compared to argon (9–17 nm). Upon oxidation, argon samples resulted in a pure LSCF phase with surface areas in the 21–29 m 2 ·g −1 range, whereas nitrogen samples contained significant impurities. This demonstrates that the size of La 2 O 3 crystallites formed during inert processing limited the ability to produce a pure LSCF phase. Symmetrical cells comprising nano-LSCF electrodes generated by the templating method were compared to cells sintered directly in air. Impedance results suggest that nano-LSCF cells and cells processed in air were dominated by interfacial charge transfer resistance and gas diffusion, respectively. The results map out conditions for preparing and integrating high surface area, nanostructured LSCF into SOFC electrodes at traditional sintering temperatures. Strategies for improving the interfacial resistance of nano-LSCF electrodes are discussed.

Muhoza, Sixbert P. (ORCID:0000000299864241)↗

DOE OSTI2026

Self-Leveling Inks for Printing Ultra-uniform Perovskite Solar Modules by Flexography

The report describes the development of scalable manufacturing methods for high-performance, stable perovskite solar modules using flexographic printing. The project developed self-leveling perovskite inks that exploit Marangoni flows to reduce coating defects and improve large-area film uniformity. Bayesian optimization was integrated with high-throughput photoluminescence mapping and photovoltaic measurements to efficiently optimize ink formulations and printing conditions. The resulting printed perovskite solar cells achieved champion power conversion efficiencies above 21.6%, with median efficiencies exceeding 20% across large device batches. At the module scale, printed devices achieved active-area efficiencies up to approximately 17.3% on 25 cm² substrates. The project also demonstrated improved performance and stability using additively patterned interconnections compared with laser-scribed controls. Overall, the work establishes a data-driven, roll-compatible pathway toward high-throughput, low-capital-cost manufacturing of uniform and stable perovskite photovoltaics.

14 SOLAR ENERGY↗

NASA NTRS1991

A special purpose silicon compiler for designing supercomputing VLSI systems

Design of general/special purpose supercomputing VLSI systems for numeric algorithm execution involves tackling two important aspects, namely their computational and communication complexities. Development of software tools for designing such systems itself becomes complex. Hence a novel design methodology has to be developed. For designing such complex systems a special purpose silicon compiler is needed in which: the computational and communicational structures of different numeric algorithms should be taken into account to simplify the silicon compiler design, the approach is macrocell based, and the software tools at different levels (algorithm down to the VLSI circuit layout) should get integrated. In this paper a special purpose silicon (SPS) compiler based on PACUBE macrocell VLSI arrays for designing supercomputing VLSI systems is presented. It is shown that turn-around time and silicon real estate get reduced over the silicon compilers based on PLA's, SLA's, and gate arrays. The first two silicon compiler characteristics mentioned above enable the SPS compiler to perform systolic mapping (at the macrocell level) of algorithms whose computational structures are of GIPOP (generalized inner product outer product) form. Direct systolic mapping on PLA's, SLA's, and gate arrays is very difficult as they are micro-cell based. A novel GIPOP processor is under development using this special purpose silicon compiler.

Venkateswaran, N.↗

NASA NTRS1999

Lithium-Ion Batteries for Aerospace Applications

This presentation reviews: (1) the goals and objectives, (2) the NASA and Airforce requirements, (3) the potential near term missions, (4) management approach, (5) the technical approach and (6) the program road map. The objectives of the program include: (1) develop high specific energy and long life lithium ion cells and smart batteries for aerospace and defense applications, (2) establish domestic production sources, and to demonstrate technological readiness for various missions. The management approach is to encourage the teaming of universities, R&D organizations, and battery manufacturing companies, to build on existing commercial and government technology, and to develop two sources for manufacturing cells and batteries. The technological approach includes: (1) develop advanced electrode materials and electrolytes to achieve improved low temperature performance and long cycle life, (2) optimize cell design to improve specific energy, cycle life and safety, (3) establish manufacturing processes to ensure predictable performance, (4) establish manufacturing processes to ensure predictable performance, (5) develop aerospace lithium ion cells in various AH sizes and voltages, (6) develop electronics for smart battery management, (7) develop a performance database required for various applications, and (8) demonstrate technology readiness for the various missions. Charts which review the requirements for the Li-ion battery development program are presented.

Surampudi, S.↗

DOE OSTI2020

Mapping valence electron distributions with multipole density formalism using 4D-STEM

Recent advancement in aberration correction and detector technology opened a door to various applications using 4D-STEM, which yields a diffraction pattern for each scanning position within a crystal unit-cell in scanning transmission electron microscopy (STEM) and generates incredible amounts of data in momentum space. Currently 4D-STEM analysis relies on the center-of-mass of the diffraction patterns in electric field and charge density mapping. It only derives the total projected charge density and is limited to phase objects, e.g. extremely thin samples. Here, we propose a new analytical method to accurately map aspherical valence electron distributions with atom-centered multipolar functions formalism using the whole 4D-STEM dataset. We demonstrate that, with the full dynamical calculations for various sample thicknesses, the method is sensitive not only to the miniscule charge transfer, but also to the atomic site symmetry and aspherical electron orbitals. The process of the refinement is much more robust and reliable than quantitative convergent beam electron diffraction.

4D-STEM↗

NASA NTRS2011

Enhancements in Deriving Smoke Emission Coefficients from Fire Radiative Power Measurements

Smoke emissions have long been quantified after-the-fact by simple multiplication of burned area, biomass density, fraction of above-ground biomass, and burn efficiency. A new algorithm has been suggested, as described in Ichoku & Kaufman (2005), for use in calculating smoke emissions directly from fire radiative power (FRP) measurements such that the latency and uncertainty associated with the previously listed variables are avoided. Application of this new, simpler and more direct algorithm is automatic, based only on a fire's FRP measurement and a predetermined coefficient of smoke emission for a given location. Attaining accurate coefficients of smoke emission is therefore critical to the success of this algorithm. In the aforementioned paper, an initial effort was made to derive coefficients of smoke emission for different large regions of interest using calculations of smoke emission rates from MODIS FRP and aerosol optical depth (AOD) measurements. Further work had resulted in a first draft of a 1 1 resolution map of these coefficients. This poster will present the work done to refine this algorithm toward the first production of global smoke emission coefficients. Main updates in the algorithm include: 1) inclusion of wind vectors to help refine several parameters, 2) defining new methods for calculating the fire-emitted AOD fractions, and 3) calculating smoke emission rates on a per-pixel basis and aggregating to grid cells instead of doing so later on in the process. In addition to a presentation of the methodology used to derive this product, maps displaying preliminary results as well as an outline of the future application of such a product into specific research opportunities will be shown.

Ellison, Luke↗

DOE OSTI2021

Identification of protein/mRNA network involving the PSORS1 locus gene CCHCR1 and the PSORS4 locus gene HAX1

Highlights: • CCHCR1 and HAX1 proteins directly interact. • CCHCR1 is a psoriasis candidate gene located on PSORS1 locus. • HAX1 gene is located on PSORS4 locus and is overexpressed in psoriasis. • CCHCR1 and HAX1 co-localize with and affect specific mRNAs in vesicles. • Novel protein/mRNA networks involving CCHCR1 and HAX1 could play a role in psoriasis. CCHCR1 (Coiled-Coil alpha-Helical Rod 1), maps to chromosomal region 6p21.3, within the major psoriasis susceptibility locus PSORS1. CCHCR1 itself is a plausible psoriasis candidate gene, however its role in psoriasis pathogenesis remains unclear. We previously demonstrated that CCHCR1 protein acts as a cytoplasmic docking site for RNA polymerase II core subunit 3 (RPB3) in cycling cells, suggesting a role for CCHCR1 in vesicular trafficking between cellular compartments. Here, we report a novel interaction between CCHCR1 and the RNA binding protein HAX1. HAX1 maps to chromosomal region 1q21.3 within the PSORS4 locus and is over-expressed in psoriasis. Both CCHCR1 and HAX1 share subcellular co-localization with mitochondria, nuclei and cytoplasmic vesicles as P-bodies. By a series of ribonucleoprotein immunoprecipitation (RIP) assays, we isolated a pool of mRNAs complexed with HAX1 and/or CCHCR1 proteins. Among the mRNAs complexed with both CCHCR1 and HAX1 proteins, there are Vimentin mRNA, previously described to be bound by HAX1, and CAMP/LL37 mRNA, whose gene product is over-expressed in psoriasis.

60 APPLIED LIFE SCIENCES↗

DOE OSTI2024

In-line, High-Throughput Quality Monitoring for Fuel Cell and Electrolyzer Components Based on Transmission and Reflection Imaging

During the manufacturing of fuel cell and electrolyzer membranes and membrane electrode assemblies (MEAs), real-time, in-line, high-throughput optical-based quality monitoring methods are essential for detecting defects and monitoring thickness variations, thus improving the performance and increasing the durability of fuel cell and electrolyzer in the hydrogen industry. For the MEAs with very opaque coatings, optical transmission-based imaging has been developed and applied in the Roll-to-Roll system using a flashlight and a high-sensitivity CCD camera. We observed high signal-to-noise ratio images while the Roll-to-Roll system ran at 5 ft/min. The entire sample image could quickly be recovered from the discrete frames using customized Python codes for automatic frame cropping and stitching. We detected significant non-uniformities in our experimental MEAs specimen. For fuel cell and low-temperature electrolysis (LTE) transparent membranes, we used optical reflectance hyperspectral imaging with interference fringe-based thickness mapping. We set up a hyperspectral camera to measure various rolls of commercial membranes. The measurement results are analyzed to find the thickness distribution of each roll and to check for defects. Transmission and reflection imaging-based quality monitoring techniques demonstrated in this project can be widely used in the mass production environment to improve the production yield and performance of hydrogen devices.

DIRECT ENERGY CONVERSION,ENGINEERING↗

DOE OSTI2021

Redshift evolution of the H2/H i mass ratio in galaxies

ABSTRACT In this paper, we present an attempt to estimate the redshift evolution of the molecular to neutral gas mass ratio within galaxies (at fixed stellar mass). For a sample of five nearby grand design spirals located on the main-sequence (MS) of star-forming galaxies, we exploit maps at 500 pc resolution of stellar mass and star formation rate (M⋆ and SFR). For the same cells, we also have estimates of the neutral (MH i) and molecular ($M_{\rm H_2}$) gas masses. To compute the redshift evolution, we exploit two relations: (i) one between the molecular-to-neutral mass ratio and the total gas mass (Mgas), whose scatter shows a strong dependence with the distance from the spatially resolved MS, and (ii) the one between $\log (M_{\rm {H_2}}/M_{\star })$ and log (MH i/M⋆). For both methods, we and that $M_{\rm H_2}$/MH i within the optical radius slightly decreases with redshift, contrary to common expectations of galaxies becoming progressively more dominated by molecular hydrogen at high redshifts. We discuss possible implications of this trend on our understanding of the internal working of high-redshift galaxies.

Morselli, Laura (ORCID:0000000307532571)↗

DOE OSTI2022

Origin of insulating and nonferromagnetic SrRuO 3 monolayers

The electro-magnetic properties of ultrathin epitaxial ruthenate films have long been the subject of debate. Here we combine experimental with theoretical investigations of (SrTiO 3 ) 5 -(SrRuO 3 ) n -(SrTiO 3 ) 5 (STO 5 -SRO n -STO 5 ) heterostructures with n = 1 and 2 unit cells, including extensive atomic-resolution scanning-transmission-electron-microscopy imaging, electron-energy-loss-spectroscopy chemical mapping, as well as transport and magneto-transport measurements. The experimental data demonstrate that the STO 5 -SRO 2 -STO 5 heterostructure is nearly stoichiometric, metallic, and ferromagnetic with T C ~ 128 K, even though it lacks the characteristic bulk-SRO octahedral tilts and matches the cubic STO structure. In contrast, the STO 5 -SRO 1 -STO 5 heterostructure features Ru-Ti intermixing in the RuO 2 layer, also without octahedral tilts, but is accompanied by a loss of metallicity and ferromagnetism. Density-functional-theory calculations show that stoichiometric n = 1 and n = 2 heterostructures are metallic and ferromagnetic with no octahedral tilts, while non-stoichiometry in the Ru sublattice in the n = 1 case opens an energy gap and induces antiferromagnetic ordering. Furthermore, the results indicate that the observed non-stoichiometry is the cause of the observed loss of metallicity and ferromagnetism in the n = 1 case.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗

DOE OSTI2020

Using Raman scattering to study reacting gas flow over a catalyst

l present a series of computational methods for analyzing and correcting Raman scattering from a reacting gas flow. My work focused on the laser diagnostic measurements of formaldehyde production over a silver catalyst, specifically the Raman spectroscopy component. This technique offers a non-intrusive, in situ way to measure the coupling between the gas phase and surface activity of a catalytic reaction at relevant industrial conditions. This report outlines the steps followed for correcting the non-idealities in the data due to both the detection optics and scattering mechanics. By implementing such refinement steps, l can generate an accurate 2D spatial map of the temperature profile, number densities for major species, and relative consumption of reactants throughout the reactor cell.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

NASA NTRS1980

Application of remote sensing to estimating soil erosion potential

A variety of remote sensing data sources and interpretation techniques has been tested in a 6136 hectare watershed with agricultural, forest and urban land cover to determine the relative utility of alternative aerial photographic data sources for gathering the desired land use/land cover data. The principal photographic data sources are high altitude 9 x 9 inch color infrared photos at 1:120,000 and 1:60,000 and multi-date medium altitude color and color infrared photos at 1:60,000. Principal data for estimating soil erosion potential include precipitation, soil, slope, crop, crop practice, and land use/land cover data derived from topographic maps, soil maps, and remote sensing. A computer-based geographic information system organized on a one-hectare grid cell basis is used to store and quantify the information collected using different data sources and interpretation techniques. Research results are compared with traditional Universal Soil Loss Equation field survey methods.

Morris-Jones, D. R.↗

NASA NTRS1991

Transient performance of fan engine with water ingestion

In a continuing investigation on effects of rain-water ingestion into bypass fan engines, it is shown that the performance of axial-flow compressors and fans is fundamentally time-dependent during ingestion of water. A code named WINCOF-I has been developed for establishing the performance of axial-flow turbomachinery operating with air-water vapor-water droplet-water film mixture, Illustrative examples of predictions and effects are provided for the case of the air-compression system of a generic bypass fan engine. Utilizing performance maps so-generated, the effects of water ingestion into the generic engine have been determined under test cell conditions simulating ingestion, flight operation (altitude and flight Mach number), and power-demand setting.

Murthy, S. N. B.↗

NASA NTRS1985

A global model of carbon-nutrient interactions

The global biogeochemical model presented has two primary objectives. First, it characterizes natural elemental cycles and their linkages for the four elements significant to Earth's biota: C, N, S, and P. Second, it describes changes in these cycles due to human activity. Global nutrient cycles were studied within the drainage basins of several major world rivers on each continent. The initial study region was the Mississippi drainage basin, concentrating on carbon and nitrogen. The model first establishes the nutrient budgets of the undisturbed ecosystems in a study region. It then uses a data set of land use histories for that region to document the changes in these budgets due to land uses. Nutrient movement was followed over time (1800 to 1980) for 30 ecosystems and 10 land use categories. A geographically referenced ecological information system (GREIS) was developed to manage the digital global data bases of 0.5 x 0.5 grid cells needed to run the model: potential vegetation, drainage basins, precipitation, runoff, contemporary land cover, and FAO soil maps of the world. The results show the contributions of land use categories to river nutrient loads on a continental scale; shifts in nutrient cycling patterns from closed, steady state systems to mobile transient or open, steady state systems; soil organic matter depletion patterns in U.S. agricultural lands; changing nutrient ratios due to land use changes; and the effect of using heavy fertilizer on aquatic systems.

Moore, Berrien, III↗

NASA NTRS1998

Calcium-independent activation of extracellular signal-regulated kinases 1 and 2 by cyclic strain

We have previously demonstrated that cyclic strain induces extracellular signal-regulated kinases 1 and 2 (ERK1/2) activation in endothelial cells (EC). The aim of this study was to investigate the effect of Ca2+ on the activation of ERK1/2. Bovine aortic EC were pretreated with a chelator of extracellular Ca2+, ethylaneglycol-bis(aminoethylether)-tetra-acetate (EGTA), a depleter of Ca2+ pools, 2,5-Di-(tert-butyl)-1,4-benzohydroquinone (BHQ), or a Ca2+ channel blocker, GdCl3, and subjected to an average 10 % strain at a rate of 60 cycles/min for 10 min. BHQ and GdCl3 did not inhibit the strain-induced ERK1/2 activation. Chelation of normal extracellular Ca2+ (1.8 mM) medium with EGTA (3 mM) acutely stimulated baseline phosphorylation and activation of ERK1/2, thereby obscuring any strain-induced activation of ERK1/2. However, in EC preincubated for 24 hours in Ca2+-free medium, elevated baseline phosphorylation was minimally activated by EGTA (200 microM) such that cyclic strain stimulated ERK1/2 in the presence or absence of BHQ. These results suggest a Ca2+ independence of the ERK1/2 signaling pathway by cyclic strain. Copyright 1998 Academic Press.

NASA Discipline Cell Biology↗