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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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Static aerodynamic characteristics of modified mercury escape and exit capsule configurations at mach numbers 0.30 to 1.4
Abort test of apollo spacecraft launch escape system
Testing plans for Apollo spacecraft escape system under simulated catastrophic launch vehicle failure
Test firing of Apollo escape system at high altitude
Separation of jettisonable-nose pilot-escape capsule investigation by means of rocket-model flight tests
Malfunction detection and escape systems during launch phase, investigating hazard types and cause
Finite-thrust escape and capture trajectories leading from circular or elliptic orbits to hyperbolic excess velocity vector located at gravitational sphere of influence
Qualification and development of Gemini escape system
Aerodynamic stability of Apollo launch escape vehicle
Full-scale flight test from sea level of abort- escape system for manned Mercury capsule
Flight test of Little Joe boosted full-scale spacecraft model and escape system for Mercury project
Static aerodynamic characteristics of modified Mercury exit and escape capsule configurations at Mach numbers 3.0 to 6.8
Environmental testing and static firing of pitch control motor for Apollo spacecraft launch escape system
Performance study for application of Saturn V to high energy earth escape missions
An application of the new optimization algorithm called Static/Dynamic Control (SDC) to design low-thrust escape and capture trajectories is presented.
The electron acceptor F4TCNQ p-dopes aggregates “nanowires” of poly(3-hexylthiophene) in nonpolar solvents but does not dope unaggregated chains. The standard free energy change for the charge transfer to form an ion pair is ΔG° et = -0.21 eV. The dissociation constant to produce free ions in toluene by DC conductivity is K° d = 1 × 10 -8 ± 50% (ΔG° d = 0.48 ± 0.05 eV). This remarkably large K°d, for ions in such a low polarity medium, may reflect interchain delocalization of the hole. The particular characteristics of this material system enables determination of both ΔG° et and ΔG° d , to find the overall free energy change from the two neutral species to completely separated ions in nonpolar media. It is endergonic by +0.27 ± 0.05 eV in contrast to -0.6 eV estimated from reported HOMO LUMO differences, illustrating the challenges that persist in determining such energetics. Steady state microwave conductivity experiments on doped aggregates confirm that holes in the aggregates cannot easily escape their dopant counterion, but at higher dopant concentrations, holes become mobile. These results provide insight into the mechanisms of charge separation involving intermolecularly delocalized charges in nonpolar media, an integral process in organic photovoltaic devices and doped molecular films.
Abstract Accurate estimates of salmonids passing Lower Granite Dam on the Snake River, by species and origin, are a critical input to assessing the status and trends of various populations as well as successful management of fisheries in the Snake River basin. Here, we describe a state-space model that estimates such escapement past a dam by using window counts, PIT tag observations, and data from an adult fish trap, accounting for issues such as nighttime passage, fallback and reascension, potential observation error at the window, and uncertainty in the adult trap rate. We tested the approach using a simulation framework that mimicked several levels of observation error, differences between nighttime passage and reascension rates, and the possibility of the adult trap being closed for some period of time. Our results demonstrate that the model produced unbiased estimates across all tested scenarios. We also applied this model to empirical data from Lower Granite Dam to produce estimates of wild, clipped hatchery, and unclipped hatchery spring/summer-run Chinook Salmon Oncorhynchus tshawytscha and steelhead O. mykiss from spawn years 2010–2019.
Across biological scales, gene-regulatory networks employ autorepression (negative feedback) to maintain homeostasis and minimize failure from aberrant expression. In this study, we present a proof of concept that disrupting transcriptional negative feedback dysregulates viral gene expression to therapeutically inhibit replication and confers a high evolutionary barrier to resistance. We find that nucleic-acid decoys mimicking cis-regulatory sites act as “feedback disruptors,” break homeostasis, and increase viral transcription factors to cytotoxic levels (termed “open-loop lethality”). Feedback disruptors against herpesviruses reduced viral replication >2-logs without activating innate immunity, showed sub-nM IC 50 , synergized with standard-of-care antivirals, and inhibited virus replication in mice. In contrast to approved antivirals where resistance rapidly emerged, no feedback-disruptor escape mutants evolved in long-term cultures. For SARS-CoV-2, disruption of a putative feedback circuit also generated open-loop lethality, reducing viral titers by >1-log. These results demonstrate that generating open-loop lethality, via negative-feedback disruption, may yield a class of antimicrobials with a high genetic barrier to resistance.