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Results for “RACEE”
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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Agentic AI and the Cyber Arms Race
Here, in this article, we examine the implications for cyberwarfare and global politics as agentic artificial intelligence becomes more powerful and enables the broad proliferation of capabilities only available to the most well-resourced actors today.
Evolutionary arms race: the role of xylan modifications in plant–pathogen interactions
This article is a Commentary on Yu et al . (2024), 244 : 1024–1040.
Local adaptation of both plant and pathogen: an arms‐race compromise in switchgrass rust
In coevolving species, parasites locally adapt to host populations as hosts locally adapt to resist parasites. Parasites often outpace host local adaptation since they have rapid life cycles, but host diversity, the strength of selection, and external environmental influence can result in complex outcomes. To better understand local adaptation in host–parasite systems, we examined locally adapted switchgrass (Panicum virgatum), and its leaf rust pathogen (Puccinia novopanici) across a latitudinal range in North America. We grew switchgrass genotypes in 10 replicated multiyear common gardens, measuring rust severity from natural infection in a ‘host reciprocal transplant’ framework for testing local adaptation. We conducted genome-wide association mapping to identify genetic loci associated with rust severity. Genetically differentiated rust populations were locally adapted to northern and southern switchgrass, despite host local adaptation to environmental conditions in the same regions. Rust resistance was polygenic, and distinct loci were associated with rust severity in the north and south. We narrowed a previously identified large-effect quantitative trait locus for rust severity to a candidate YELLOW STRIPE-LIKE gene and linked numerous other loci to defense-related genes. Overall, our results suggest that both hosts and parasites can be simultaneously locally adapted, especially when parasites impose less selection than other environmental factors.
Data Race Detection Using Large Language Models
Explore the source record for details and available documents.
The Race to Electronic Photography
A participant in some of the Kodak Research Lab's early efforts in CCD-based imaging shares a view of the company's contribution to the development of digital cameras.
19-LW-045 Full Length Final Report. Molecular Mechanisms of Bacterial Pathogenesis: Waging the Arms Race with Superbugs
As the current global pandemic makes abundantly clear, we need a better understanding of infectious disease to safeguard human health, the economy and global security. Modern omics techniques hold the promise of providing a comprehensive understanding of the molecular mechanisms of life, including causes of pathogenesis from infectious disease at the molecular level, but we there is a serious gap in annotation of gene function. For as much as half of the genes and gene products encoded in genomes the molecular and/or cellular function is unknown or only partially understood. Recent innovations in fluorescence microscopy for live cell imaging and genetic engineering make it possible to determine the temporal correlation between molecular events, such as a gene being expressed due to host-pathogen interaction, and cellular events, such as bacterial invasion of immune cells. This is turn allows us to gain new insight as to the molecular and cellular role of individual genes and will enable the discovery and validation of new molecular mechanisms essential for infectious disease. Knowing the molecular mechanisms of disease processes will provide new therapeutic targets or novel countermeasure strategies. We aimed to develop a lattice light sheet fluorescence microscope as a unique resource at LLNL for long time course live cell imaging experiments; to develop the reagents and cell lines needed to monitor molecular events during the course pathogenic bacteria infecting mammalian immune cells; and to demonstrate that we could capture molecular events during an infection. We fully commissioned the LLNL lattice light sheet microscope and conducted initial proof of principle imaging experiments on mammalian immune cells and pathogenic bacteria. It is clear from the experience gained that long time course live cell imaging has tremendous potential to help elucidate molecular mechanisms of host-pathogen interactions and to help annotate gene function, which would establish a basis for new countermeasures. It is also clear that if live cell imaging is to realize its full potential new data processing and analysis tools will need to be developed to facilitate analysis of molecular events within cells; new sample chambers and stages could facilitate studies with a wider range of cell and tissue types; and alternative molecular tagging methods need to be explored to enable more facile engineering of cells labeled with molecular specificity.
RACEE Energy Efficiency Implementation for Holy Cross, Alaska (Final Report)
The Deg Hit’an Athabascan village of Holy Cross is located along the Ghost Creek Slough bank of the Yukon River. Holy Cross is home to almost 170 people who are accustomed to both the advantages and disadvantages of living off the road system - the nearest major road is some 300 miles to the east. On one hand, Holy Cross residents have greater access to practicing traditional activities like subsistence hunting and fishing. Families in the area have fished, hunted, and gathered food together for many generations and the land is imbued with this special history. But compared to Alaskans living on the road system, the residents of Holy Cross pay higher prices for basic necessities since goods are transported via air service and seasonal barge shipments. Holy Cross residents also accumulate higher energy costs, as diesel fuel is the primary fuel source for heating and lighting and costs over $\$6$ per gallon. Affording these high living costs becomes a barrier for Holy Cross residents who want to stay in the village or participate in subsistence activities requiring transportation by boat or ATV.
The Near Term Race for the Neutrino Mass Ordering
The muon neutrino disappearance experiments T2K and NOvA, measure a different combination of Delta m^2_31 and Delta m^2_32 then the electron neutrino disappearance experiments Daya Bay and JUNO. This can be used to determine the neutrino mass ordering, one of the outstanding questions of the neutrino sector. In this talk I will explain why this happens and what is the current state and future prospects for the mass ordering determination using this method.
RACEE: Port Lions Community Energy Efficiency Project
The City of Port Lions is one of several villages located on Kodiak Island in the Gulf of Alaska. Founded in 1964, Port Lions was built through the joint efforts of the Bureau of Indian Affairs, Lions International, the Public Health Service, and other organizations for the displaced residents of Afognak which was destroyed by a tsunami caused by the Good Friday Earthquake.
Trends in US Pediatric Asthma Hospitalizations, by Race and Ethnicity, 2012–2020
Not provided.
Effect of ball-race conformity on spinning friction
Spinning friction and torque dependence on ball bearing-groove conformity
Arched-outer-race ball-bearing analysis considering centrifugal forces
A first-order thrust load analysis that considers centrifugal forces but which neglects gyroscopics, elastohydrodynamics, and thermal effects was performed. The analysis was applied to a 150-mm-bore angular-contact ball bearing. Fatigue life, contact loads, and contact angles are shown for conventional and arched bearings. The results indicate that an arched bearing is highly desirable for high-speed applications. In particular, at an applied load of 4448 n (1000 lb) and a DN value of 3 million (20,000 rpm) the arched bearing shows an improvement in life of 306 percent over that of a conventional bearing.
Analysis of an arched outer-race ball bearing considering centrifugal forces.
Thrust-load analysis of a 150-mm angular contact ball bearing, taking into account centrifugal forces but omitting gyroscopics, elastohydrodynamics, and thermal effects. A Newton-Raphson method of iteration is used to evaluate the radial and axial projection of the distance between the ball center and the outer raceway groove curvature center. Fatigue life of the bearing is evaluated. Results for life, contact loads, and angles are given for a conventional bearing and two arched bearings.
Evaluation of outer race tilt and lubrication on ball wear and SSME bearing life reductions
Several aspects of the SSME bearing operation were evaluated. The possibility of elastohydrodynamics (EHD) lubrication with a cryogenic fluid was analyzed. Films as thick as .61 microns were predicted with one theory which may be thick enough to provide hydrodynamic support. The film formation, however, is heavily dependent on good surface finish and a low bulk bearing temperature. Bearing dynamics to determine if the radial stiffness of a bearing which are dependent on bearing misalignment were analyzed. Four ball tests were conducted at several environmental conditions from an LN2 bath to 426 C in air. Surface coatings and ball materials are evaluated. Severe wear and high friction are measured for all ball materials except when the balls have surface lubricant coatings.
Graphics enhanced computer emulation for improved timing-race and fault tolerance control system analysis
A computer simulation system has been developed for the Space Shuttle's advanced Centaur liquid fuel booster rocket, in order to conduct systems safety verification and flight operations training. This simulation utility is designed to analyze functional system behavior by integrating control avionics with mechanical and fluid elements, and is able to emulate any system operation, from simple relay logic to complex VLSI components, with wire-by-wire detail. A novel graphics data entry system offers a pseudo-wire wrap data base that can be easily updated. Visual subsystem operations can be selected and displayed in color on a six-monitor graphics processor. System timing and fault verification analyses are conducted by injecting component fault modes and min/max timing delays, and then observing system operation through a red line monitor.