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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 19 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2018

Augmented neutrophil extracellular traps formation promotes atherosclerosis development in socially defeated apoE −/− mice

Highlights: • Repeated social defeat exaggerates plaque size in apoE{sup −/−} mice. • Proportion of circulating neutrophils is significantly increased in defeated mice. • In vivo NETs formation is exaggerated within the atherosclerotic lesions in defeated mice. • DNase I treatment abrogates pro-atherogenic effect of RSD exposure. • In vitro NETs formation is exaggerated in BM PMN-MDSC from defeated mice. Depression is an independent risk factor of cardiovascular disease (CVD); however, the causal association remains undefined. We exposed mice to repeated social defeat (RSD) to precipitate depressive-like behaviors, and investigated the effects on atherosclerosis. Eight-week-old male apoE{sup −/−} mice were exposed to RSD by housing with a larger CD-1 mouse in a shared home cage. They were subjected to vigorous physical contact daily for 10 consecutive days and fed a high-cholesterol diet (HCD) for 6 weeks. The social interaction ratio and immobility time showed dramatic social avoidance before and after HCD feeding. Defeated mice showed higher increase in atherosclerotic lesion areas in the aortic root and entire aorta than control mice. Mean blood pressure and lipid profile were equivalent in both groups. While Ly-6G- and Mac3-positive areas in the aortic root were comparable between the groups, citrullinated histone H3 (Cit-H3)- and myeloperoxidase (MPO)-positive areas, markers of neutrophil extracellular traps (NETs), were significantly increased in the defeated mice. Treatment with DNase I completely diminished the exaggerated atherosclerosis. The proportion of peripheral blood polymorphonuclear myeloid-derived suppressor cells (PMN-MDSC), but not of inflammatory monocytes, was markedly increased. Moreover, in vitro NETs formation from bone marrow (BM) PMN-MDSC was markedly augmented, accompanied by higher expression of Nox2 gene and reactive oxygen species. Our findings demonstrate that exposure to RSD promotes atherosclerosis by augmenting NETs formation within the plaque. This provides new insight into the underlying mechanism of depression-related CVD.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2024

Cyber-Informed Engineering (CIE) Guidance to Defeat Systematic OT Weaknesses

This research summary outlines the University of Illinois Information Trust Institute (ITI) team's evaluation of whether applying the 12 Cyber-Informed Engineering (CIE) Principles could reduce or eliminate weaknesses identified by the SEI-ETF in engineered systems. ITI's findings suggest that applying CIE principles to weaknesses in MITRE CWE View 1358 can potentially mitigate or eliminate those vulnerabilities.

42 ENGINEERING↗
DOE OSTI2019

Defeat system for vehicle attached improvised explosive devices

An explosive device detection and expulsion system broadly comprising a detection subsystem for sensing an IED attached to a vehicle and an expulsion subsystem for expelling the IED from the vehicle. The detection subsystem includes a sensor for detecting an IED via an electromagnetic field change or capacitance change, vibrations, and/or heat, and a controller for activating the expulsion subsystem upon receiving a detection signal from the sensor. The expulsion subsystem includes a deployable panel configured to be attached to the vehicle and a deployable mechanism for shifting the deployable panel from an undeployed state to a deployed state so as to expel the IED from the vehicle.

45 MILITARY TECHNOLOGY, WEAPONRY, AND NATIONAL DEF↗
DOE OSTI2019

DEFEATING THERMAL RUNAWAY

Supposedly “safe” ,“discharged” lithium-ion batteries have exploded while being transported to recycling plants. Because of the Carbon- Lithium in the battery, they must be shipped as Class 9 Hazardous Materials, which is costly and inefficient. Here, we demonstrate elimination of thermal runaway for end-of-life lithium-ion batteries using supercritical CO2 to remove flammability hazards. Deactivation of worst-case scenario (charged) batteries from electric buses is successfully demonstrated.

advanced battery recycling↗
DOE OSTI2021

Detection and Defeat of Autonomous Sensors

Presentation to be made a the June 15 works in progress (WIPs) WebEx. The presentation will be later uploaded to the Science & Technology website.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2021

Defeat system for vehicle attached improvised explosive devices

An explosive device detection and expulsion system broadly comprising a detection subsystem for sensing an IED attached to a vehicle and an expulsion subsystem for expelling the IED from the vehicle. The detection subsystem includes a sensor for detecting an IED via an electromagnetic field change or capacitance change, vibrations, and/or heat, and a controller for activating the expulsion subsystem upon receiving a detection signal from the sensor. The expulsion subsystem includes a deployable panel configured to be attached to the vehicle and a deployable mechanism for shifting the deployable panel from an undeployed state to a deployed state so as to expel the IED from the vehicle.

Hower, Brent↗
DOE OSTI2021

Investigating the relationship between radial pre-stress magnitude and ballistic projectile dwell in heavy confined ceramic targets

A series of bare silicon carbide ceramic armour disks were manufactured with high-strength steel containment to induce varying magnitudes of radial pre-stress. The induced radial stresses, ranging from 0 to 900 MPa, were measured via neutron diffraction and verified by comparison with numerical calculations. Four targets of each configuration, referred to as slip-fit, moderate pre-stress, and high pre-stress, were subject to ballistic testing with hemispherical-nose, tungsten heavy alloy long rod projectiles to determine the interface defeat transition velocity. In-situ diagnostics were unsuccessful in aiding the identification of interface defeat, necessitating a reliance on post-mortem assessment. A transition velocity of approx. 1000 m/s was identified for the unstressed target, increasing to approx. 1200 m/s for the pre-stressed configurations. No performance effect was discernible between the moderate (372 MPa) and high (899 MPa) pre-stress configurations, suggesting that an optimal performance may be achieved for lower pre-stress levels (i.e., <372 MPa). Additionally, the test results were compared with four semi-analytical predictions of interface defeat performance and good agreement was found, albeit with significant range in the model predictions.

42 ENGINEERING↗
DOE OSTI2016

A graphite oxide (GO)-based remote readable tamper evident seal

Here, this paper presents a prototype of a remotely readable graphite oxide (GO) paper-based tamper evident seal. The proposed device combines the tunable electrical properties offered by reduced graphite oxide (RGO) with a compressive sampling scheme. The benefit of using RGO as a tamper evident seal material is the sensitivity of its electrical properties to the common mechanisms adopted to defeat tamper-evident seals. RGO’s electrical properties vary upon local stress or cracks induced by mechanical action (e.g., produced by shimming or lifting attacks). Further, modification of the seal’s electrical properties can result from the incidence of other defeat mechanisms, such as temperature changes, solvent treatment and steam application. The electrical tunability of RGO enables the engraving of a circuit on the area of the tamper evident seal intended to be exposed to malicious attacks. The operation of the tamper evident seal, as well as its remote communication functionality, is supervised by a microcontroller unit (MCU). The MCU uses the RGO-engraved circuitry to physically implement a compressive sampling acquisition procedure. The compressive sampling scheme provides the seal with self-authentication and self-state-of-health awareness capabilities. Finally, the prototype shows potential for use in low-power, embedded, remote-operation nonproliferation security related applications.

36 MATERIALS SCIENCE↗
DOE OSTI2019

Authentication Protocol for ICS without Encryption

Industrial control systems (ICS) describes the different types of control systems and associated instrumentation, which includes the devices, systems, networks, and controls used to operate and/or automate industrial processes. Depending on the industry, each ICS functions differently and are built to electronically manage tasks efficiently. Historically, industrial plants have included networking, and changes have been made over time without consideration for security. Many ICS devices currently have inadequate security features. Adding encryption in ICS is undesirable because many of the new detection method involves deep packet inspection. Therefore, we propose to develop a method of providing authentication between devices without encrypting the data. This testbed design will allow rapid development and experimentation with Cyber Physical Systems. Modbus connects to a supervisory computer with a Remote Terminal Unit (RTU) in Supervisory Control and Data Acquisition (SCADA) systems. Our project seeks to enhance security in the ICS environment by adding device authentication to the lower levels of the plant floor. This approach was selected as it allows verification of the sender of data from level 1/level 0 devices up to supervisory systems. This addition is desirable as it adds enhanced verification to the integrity of system data without obscuring (via encryption) the data being transmitted across the network. This is important because many ICS systems are real time critical (decryption adds to latency) and many other good security options require deep packet inspection (which encryption completely defeats). To accomplish this, a proof of concept of adding an authentication scheme was designed and will be tested with a common ICS protocol. The setup includes a single serial cable connecting the serial ports on two devices, a Master and a Minion. Authentication will occur in the following methods: - Data layer involving Transport Layer Security/Secure Socket Layer (TLS/SSL); - TCP/IP route implementation; - Key exchange algorithm; - Raspberry Pi programming for authentication. A portion of the setup includes adding Raspberry Pi into the system as the device is handling the authentication for the network traffic. Modbus is the chosen ICS protocol. It is used to transmit signals from instrumentation and control devices back to a main controller or data gathering system. Typically, the device identity is assumed but not verified. For verifying device identity, we constructed a digital signature architecture with TLS. A novel adaptation of this is to use only the digital signature that is provided and not the encryption capability. This allows ICS traffic to flow unobscured while still providing verification for the integrity of the data. Verification of this process will involve adding additional I/O level network devices with spoofed IP addresses and detecting the authenticated versus unauthenticated traffic. Our TLS implementation will have encryption disabled but should still allow for digital signing of data. This will enable our system to distinguish between real end devices and spoofed end devices. This experiment is presently building the test setup. It is focusing on a small setting to identify authenticated and unauthenticated devices on the network. This should allow for scaling to a larger network size after the initial proof of concept. One concern with this scheme is a certificate deployment has a large scale key management. Network size will thus increase the key management task for security. In addition, we believe that further research should be done on exploring the use of this method to defeat man-in-the-middle attacks.

42 ENGINEERING↗
DOE OSTI2022

A Bayesian View on the Dr. Evil Scenario

Abstract In Defeating Dr. Evil with Self-Locating Belief , Adam Elga proposes and defends a principle of indifference for self-locating beliefs: if an individual is confident that his world contains more than one individual who is in a state subjectively indistinguishable from his own, then he should assign equal credences to the hypotheses that he is any one of these individuals. Through a sequence of thought experiments, Elga in effect claims that he can derive the credence function that should apply in such situations, thus justifying his principle of indifference. Here we argue, using a Bayesian approach, that Elga’s reasoning is circular: in analyzing the third of his thought experiments, he uses an assertion that is justifiable only if one assumes, from the start, the principle of indifference that he is attempting to justify. We agree with Elga that the assumption of equal credences is a very reasonable principle, in the absence of any reason to assign unequal credences, but we do not agree that the equality of credences can be so derived.

Azhar, Feraz↗
DOE OSTI2024

Two pathways to understanding electron transfer in reaction centers from photosynthetic bacteria: A comparison of Rhodobacter sphaeroides and Rhodobacter capsulatus mutants

The rates, yields, mechanisms and directionality of electron transfer (ET) are explored in twelve pairs of Rhodobacter (R.) sphaeroides and R. capsulatus mutant RCs designed to defeat ET from the excited primary donor (P*) to the A-side cofactors and re-direct ET to the normally inactive mirror-image B-side cofactors. In general, the R. sphaeroides variants have larger P + H B - yields (up to similar to ~90%) than their R. capsulatus analogs (up to similar to ~60%), where H B is the B-side bacteriopheophytin. Substitution of Tyr for Phe at L-polypeptide position L181 near B B primarily increases the contribution of fast P* → P + B B - → P + H B - two-step ET, where B-B is the "bridging" B-side bacteriochlorophyll. The second step (similar to ~6-8 ps) is slower than the first (similar to ~3-4 ps), unlike A-side two-step ET (P* → P + B A - → P + H A - ) where the second step (similar to ~1 ps) is faster than the first (similar to ~3-4 ps) in the native RC. Substitutions near H B , at L185 (Leu, Trp or Arg) and at M-polypeptide site M133/131 (Thr, Val or Glu), strongly affect the contribution of slower (20-50 ps) P* → P + H B - one-step superexchange ET. Here, both ET mechanisms are effective in directing electrons "the wrong way" to H B and both compete with internal conversion of P* to the ground state (similar to ~200 ps) and ET to the A-side cofactors. Collectively, the work demonstrates cooperative amino-acid control of rates, yields and mechanisms of ET in bacterial RCs and how A- vs. B-side charge separation can be tuned in both species.

Charge Separation↗
DOE OSTI2018

Viewing internal bubbling and microexplosions in combusting metal particles via x-ray phase contrast imaging

The combustion performance of metal particles for explosives, propellants, pyrotechnics, and bio-agent defeat can be optimized by controlling the chemistry, size, and coatings of the particles. Many pure and composite metal fuels used in these applications have been observed to microexplode during combustion. This causes particles to fragment, revealing fresh surfaces, which may enhance burn rates and efficiencies. Despite these potential benefits, few have attempted to control the bubbling and the microexplosion of metal powders as they combust in molten states. Here, we choose Al:Zr composite powders as a representative system to study bubbling and microexplosions and to identify active mechanisms. Using synchrotron x-rays and phase contrast imaging, we observe molten metal particles of various sizes as they burn in air at temperatures ranging from 2700 to 3500 K. We characterize bubble nucleation and growth in the interior of the particles during the combustion process, and we identify heterogeneous nucleation, slow growth and coalescence of bubbles, as well as rapid bubble growth leading to microexplosions. Bubble growth rates and Laplace pressures are calculated, and we find that during slow expansion growth rates are similar to classical predictions of bubble growth in superheated liquids. For rapid expansions we find that a critical growth rate of ~0.5m s –1 , independent of the initial particle size, is necessary to enable microexplosions. We calculate the rate of gas generation that is needed to enable this growth and we conclude that nitrogen is the gas most likely driving rapid bubble growth and fragmentation. Furthermore these results provide the first in situ observations of the mechanisms that control bubbling and microexplosions during the combustion of metal particles.

36 MATERIALS SCIENCE↗
DOE OSTI2023

Analytical population dynamics underlying harmful algal blooms triggered by prey avoidance

A modified version of the NPZD ecosystem model is used to analytically examine the effects of predation avoidance, a possible mechanism for triggering harmful algal blooms (HAB). To resolve HAB development caused by predation avoidance, an additional phytoplankton functional group is considered, one that has slower nutrient uptake and better predation avoidance characteristics than the non-harmful phytoplankton group used in traditional NPZD models. Because the two phytoplankton groups (one non-harmful and one HAB) compete for only one resource within the same system, steady state (equilibrium) conditions cannot occur without the presence of zooplankton; only the non-harmful phytoplankton group, which defeats the HAB group in the resource competition, can survive in the equilibrium. The presence of sufficient zooplankton effectively acts to replenish the nutrient pool by consuming the non-harmful phytoplankton. When this occurs, two equilibrium states are found: one with both phytoplankton groups coexisting, and one that only includes the HAB group. Further, the condition required for equilibrium is that the total nitrogen within the system should be larger than a threshold determined by model coefficients. The threshold and feasibility of the equilibrium are sensitive to the relative HAB predation avoidance coefficient. If the coefficient is larger than the ratio of net growth rates between the HAB and non-harmful phytoplankton group, the threshold becomes infinite, and an equilibrium is not feasible. The time scale for the system to reach an equilibrium state that includes a HAB group is determined asymptotically. The dependence of a threshold condition as a controlling factor may explain the regime shift of dominant species causing HABs. The ecosystem model is fully implemented into the Regional Ocean Modeling System and applied to an idealized coastal embayment (with depths and geometry taken from San Francisco Bay) to show numerically the dominance of prey avoidance dynamics in a natural shallow water environment that includes advection and diffusion. The analytical results improve strategies for HAB modeling and provide guidance for setting model coefficients necessary to resolve a HAB event.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2021

An analysis of controlled detachment by seeding various impurity species in high performance scenarios on DIII-D and EAST

Experiments at DIII-D and EAST have demonstrated simultaneous high confinement, divertor detachment, and active control of detachment level, all of which are required for ITER. Comparing detachment control via T e and J sat , it appears that is the most straightforward sensor to use for accessing detachment onset, while J sat offers more precise control of degree of detachment. Based on these results, control using nitrogen seeding has so far shown the best ability to follow a target value with the low disruptivity and little to no degradation of performance when an Internal Transport Barrier (ITB) is present, but not all facilities allow its use. Neon seeding also can be paired with feedback control with low impact on core performance as long as there is no disruption, however shots with neon seeding commonly disrupted during these experiments. Argon is effective in EAST, but tends to degrade performance (by ≈ 10%β p ) when detachment is achieved. With ideal conditions and strike point position control, data from a single Langmuir probe are an acceptable input to the control algorithm, but this simple system is easily defeated by strike point displacement comparable to the T e or J sat scale lengths. The presence of an ITB seems to be critical to retaining core performance in detachment in these parameter ranges, as the pedestal pressure tends to decrease as a result of impurity seeding.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
DOE OSTI2020

The role of infrastructure to enable and support electric drive vehicles: A Transportation Research Part D Special Issue

Widespread vehicle electrification appears to be necessary to achieve timely and deep reductions in greenhouse gases (GHG) and pollutant emissions as well as petroleum use in the transportation sector. The lack of a sufficient refuelling infrastructure has defeated many past efforts to promote alternatives to petroleum fuels. The papers in this special issue on the “Role of Infrastructure to Enable and Support Electric Drive Vehicles” address the diverse challenges posed by a transition from fossil-fuelled internal combustion engine vehicles to vehicles powered by electric motors and the special role of refuelling/recharging infrastructure in this transition. Electric drive vehicles are herein considered to be plug-in electric vehicles (PEVs), including plug-in hybrid electric vehicles (PHEVs), battery electric vehicles (BEVs), and hydrogen fuel cell electric vehicles (FCEVs). BEVs and FCEVs are also known as Zero Emission Vehicles (ZEVs) because their propulsion systems produce no tailpipe emissions.

33 ADVANCED PROPULSION SYSTEMS↗