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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 1,477 records · Page 82
All sourcesNASA NTRSDOE OSTI
DOE OSTI2017

Xenobiotics and the Glucocorticoid Receptor

Glucocorticoid Receptor (GR) is present in virtually every human cell type. Representing a nuclear receptor superfamily, GR has several different isoforms essentially acting as ligand-dependent transcription factors, regulating glucocorticoid-responsive gene expression in both a positive and a negative manner. Although the natural ligand of the Glucocorticoid Receptor, glucocorticoids (GC) represent only some of the multiple ligands for GR. Xenobiotics, ubiquitous in the environment, bind to GR and are also capable of activating or repressing GR gene expression, thereby modulating GR cell and tissue-specific downstream effects in a multitude of ways that include responses to inflammatory, allergic, metabolic, neoplastic and autoimmune processes. Many xenobiotics, if inadequately metabolized by xenobiotic metabolizing enzymes and not wholly eliminated, could have deleterious toxic effects with potentially lethal consequences. This review examines GR, the genomic and non-genomic actions of natural and synthetic GC and the body's handling of xenobiotic compounds, before reviewing what is presently known about GR's interactions with many of the more commonly encountered and some of the less well known GR-associated xenobiotics. GR promiscuity and crosstalk with other signaling pathways is discussed, alongside novel roles for GR that include mood disorder and addiction. A knowledge of GR interactions with xenobiotics is increasingly relevant when considering aging populations and the related prevalence of neoplastic disease, together with growing concerns around human exposure to mixtures of chemicals in the environment. Furthermore, escalating rates of obesity, Type 2 diabetes; autoimmune, allergy, addiction and mood disorder-related pathologies, require novel targeted interventions and GR appears a promising pharmacological candidate. - Highlights: • Biological impact of xenobiotics acting through Glucocorticoid Receptor. • Promiscuity of Glucocorticoid Receptor. • Involvement of Glucocorticoid Receptor in multiple pathologies. • Novel xenobiotic ligands for Glucocorticoid Receptor. • Potential for multifaceted Glucocorticoid Receptor-targeted pharmacological interventions.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2015

Public perception of hazardousness caused by current trends of municipal solid waste management

Highlights: • Contribution to the scientific literature by examining the relationship between concern for the environment and waste disposal in the frame of household waste treatment mechanism specifically in developing countries. • The awareness of the citizens satisfaction level and the local existing capacities in developing countries significantly contribute to decision making on MSW management sustainability in Palestine and other developing countries when applied. • Identification of the differences and similarities among DC resulting to failures or success in WM field. - Abstract: Municipal solid waste (MSW) piling up is becoming a serious problem in all developing countries (DC) as a result of inequitable waste collection and treatment. Citizens’ collaboration is partly based on understanding their views and their active involvement in MSW planning; on the other hand the assessment of the perception of hazardousness related with MSW is considered rather important as well since the identification of the weak points of the applied MWM strategy is eased and the level of required training is determined. Researchers implemented a case study in the West Bank (WB) and Gaza Strip (GS) regions of Palestine, taking into consideration previous researches in other developing countries. They reached to safe and useful conclusions regarding the parameters which mean the greatest in the waste management field as far as DC are concerned. Lack of skilled manpower, irregular collection services, inadequate equipment used for waste collection, inadequate legal provisions, and resource constraints are additional factors that are confirmed to be challenging the waste management scenarios in all DCs today. The research takes those factors under consideration but focuses on the educational gap and the results revealed interesting trends a significant relationship between respondent’s educational attainment and their awareness of hazardous waste (hazard perception); the results will indicate the measure taking required to avoid accidents occurred in those regions (burns from toxics, cuts from sharps, etc). National policy and legislation development based on the research outcomes will ensure equitable and accessible services are in place in order to move towards a healthier environment. Specialized health education and training programs on national scale are also needed to enhance awareness on hazardous waste.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2015

Cross-current leaching of indium from end-of-life LCD panels

Graphical abstract: Display Omitted - Highlights: • End-of-life LCD panels represent a source of indium. • Several experimental conditions for indium leaching have been assessed. • Indium is completely extracted with 2 M sulfuric acid at 80 °C for 10 min. • Cross-current leaching improves indium extraction and operating costs are lowered. • Benefits to the environment come from reduction of CO{sub 2} emissions and reagents use. - Abstract: Indium is a critical element mainly produced as a by-product of zinc mining, and it is largely used in the production process of liquid crystal display (LCD) panels. End-of-life LCDs represent a possible source of indium in the field of urban mining. In the present paper, we apply, for the first time, cross-current leaching to mobilize indium from end-of-life LCD panels. We carried out a series of treatments to leach indium. The best leaching conditions for indium were 2 M sulfuric acid at 80 °C for 10 min, which allowed us to completely mobilize indium. Taking into account the low content of indium in end-of-life LCDs, of about 100 ppm, a single step of leaching is not cost-effective. We tested 6 steps of cross-current leaching: in the first step indium leaching was complete, whereas in the second step it was in the range of 85–90%, and with 6 steps it was about 50–55%. Indium concentration in the leachate was about 35 mg/L after the first step of leaching, almost 2-fold at the second step and about 3-fold at the fifth step. Then, we hypothesized to scale up the process of cross-current leaching up to 10 steps, followed by cementation with zinc to recover indium. In this simulation, the process of indium recovery was advantageous from an economic and environmental point of view. Indeed, cross-current leaching allowed to concentrate indium, save reagents, and reduce the emission of CO{sub 2} (with 10 steps we assessed that the emission of about 90 kg CO{sub 2}-Eq. could be avoided) thanks to the recovery of indium. This new strategy represents a useful approach for secondary production of indium from waste LCD panels.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2024

The vertical-velocity skewness in the inertial sublayer of turbulent wall flows

Empirical evidence is provided that within the inertial sublayer (i.e. logarithmic region) of adiabatic turbulent flows over smooth walls, the skewness of the vertical-velocity component 𝑆 𝑤 displays universal behaviour, being a positive constant and constrained within the range 𝑆 𝑤 ≈ 0.1–0.16, regardless of flow configuration and Reynolds number. A theoretical model is then proposed to explain this behaviour, including the observed range of variations of 𝑆 𝑤 . The proposed model clarifies why 𝑆 𝑤 cannot be predicted from down-gradient closure approximations routinely employed in large-scale meteorological and climate models. The proposed model also offers an alternative and implementable approach for such large-scale models.

turbulent boundary layers↗
DOE OSTI2016

Isotopic evidence for reductive immobilization of uranium across a roll-front mineral deposit

We use uranium (U) isotope ratios to detect and quantify the extent of natural U reduction in groundwater across a roll front redox gradient. Our study was conducted at the Smith Ranch-Highland in situ recovery (ISR) U mine in eastern Wyoming, USA, where economic U deposits occur in the Paleocene Fort Union formation. To evaluate the fate of aqueous U in and adjacent to the ore body, we investigated the chemical composition and isotope ratios of groundwater samples from the roll-front type ore body and surrounding monitoring wells of a previously mined area. The 238 U/ 235 U of groundwater varies by approximately 3‰ and is correlated with U concentrations. Fluid samples down-gradient of the ore zone are the most depleted in 238 U and have the lowest U concentrations. Activity ratios of 234 U/ 238 U are ~5.5 up-gradient of the ore zone, ~1.0 in the ore zone, and between 2.3 and 3.7 in the down-gradient monitoring wells. High-precision measurements of 234 U/ 238 U and 238 U/ 235 U allow for development of a conceptual model that evaluates both the migration of U from the ore body and the extent of natural attenuation due to reduction. We find that the premining migration of U down-gradient of the delineated ore body is minimal along eight transects due to reduction in or adjacent to the ore body, whereas two other transects show little or no sign of reduction in the down-gradient region. Lastly, these results suggest that characterization of U isotopic ratios at the mine planning stage, in conjunction with routine geochemical analyses, can be used to identify where more or less postmining remediation will be necessary.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2017

Two-Stage Fracturing Wastewater Management in Shale Gas Development

Here, management of shale gas wastewater treatment, disposal, and reuse has become a significant environmental challenge, driven by an ongoing boom in development of U.S. shale gas reservoirs. Systems-analysis based decision support is helpful for effective management of wastewater, and provision of cost-effective decision alternatives from a whole-system perspective. Uncertainties are inherent in many modeling parameters, affecting the generated decisions. In order to effectively deal with the recourse issue in decision making, in this work a two-stage stochastic fracturing wastewater management model, named TSWM, is developed to provide decision support for wastewater management planning in shale plays. Using the TSWM model, probabilistic and nonprobabilistic uncertainties are effectively handled. The TSWM model provides flexibility in generating shale gas wastewater management strategies, in which the first-stage decision predefined by decision makers before uncertainties are unfolded is corrected in the second stage to achieve the whole-system’s optimality. Application of the TSWM model to a comprehensive synthetic example demonstrates its practical applicability and feasibility. Optimal results are generated for allowable wastewater quantities, excess wastewater, and capacity expansions of hazardous wastewater treatment plants to achieve the minimized total system cost. The obtained interval solutions encompass both optimistic and conservative decisions. Trade-offs between economic and environmental objectives are made depending on decision makers’ knowledge and judgment, as well as site-specific information. In conclusion, the proposed model is helpful in forming informed decisions for wastewater management associated with shale gas development.

04 OIL SHALES AND TAR SANDS↗
DOE OSTI2018

Liquid-Like, Self-Healing Aluminum Oxide during Deformation at Room Temperature

Effective protection from environmental degradation relies on the integrity of oxide as diffusion barriers. Ideally, the passivation layer can repair its own breaches quickly under deformation. While studies suggest that the native aluminum oxide may manifest such properties, it has yet to be experimentally proven because direct observations of the air-environmental deformation of aluminum oxide and its initial formation at room temperature are challenging. In this letter, we report in situ experiments to stretch pure aluminum nanotips under O 2 gas environments in a transmission electron microscope (TEM). We discovered that aluminum oxide indeed deforms like liquid and can match the deformation of Al without any cracks/spallation at moderate strain rate. At higher strain rate, we exposed fresh metal surface, and visualized the self-healing process of aluminum oxide at atomic resolution. Unlike traditional thin-film growth or nanoglass consolidation processes, we observe seamless coalescence of new oxide islands without forming any glass–glass interface or surface grooves, indicating greatly accelerated glass kinetics at the surface compared to the bulk.

36 MATERIALS SCIENCE↗
DOE OSTI2025

Can Restoring Tidal Wetlands Reduce Estuarine Nuisance Flooding of Coasts Under Future Sea‐Level Rise?

Wetland restoration is an increasingly popular nature‐based method for flood risk mitigation in coastal communities. In this study, we present a novel method using hydrodynamic modeling and harmonic analysis to quantify wetlands' ability to reduce future nuisance flooding. The method leverages a hydrodynamic model calibrated to present day data and was run for a range of future sea‐level rise (SLR) and wetland restoration scenarios to quantify changes to tidal harmonic amplitudes and phases. The harmonic constituents are used to generate water surface elevations over a time period of interest (e.g., one year) and compared to critical exceedance thresholds such as levee elevations. Then, changes to nuisance flooding are calculated by counting the number of hours critical thresholds are exceeded under different SLR and wetland restoration scenarios. We applied the method to Coos Bay, Oregon, USA as a test case. We found restoration reduces the number of hours nuisance flooding occurs in downtown Coos Bay from 15 hr (present day conditions) to 0 hr (fully restored condition) under median SLR (82 cm by 2100). Restoration had spatially variable impacts on reducing peak flood elevations with minimal impacts near the estuary mouth and greatest impact 32 km inland. The effectiveness of restoration was heavily dependent on future SLR. Restoration was maximally effective in 2050 under all SLR scenarios, less effective in 2100 under median SLR, and not effective under high SLR. Modeling results suggest increased tidal prism and accommodation space are driving restoration‐associated reductions in tidal amplitudes.

Brand, Matthew W. [Louisiana State Univ., Baton Ro↗
DOE OSTI2024

Discovery of atomic clock-like spin defects in simple oxides from first principles

Virtually noiseless due to the scarcity of spinful nuclei in the lattice, simple oxides hold promise as hosts of solid-state spin qubits. However, no suitable spin defect has yet been found in these systems. Using high-throughput first-principles calculations, we predict spin defects in calcium oxide with electronic properties remarkably similar to those of the NV center in diamond. These defects are charged complexes where a dopant atom — Sb, Bi, or I — occupies the volume vacated by adjacent cation and anion vacancies. The predicted zero phonon line shows that the Bi complex emits in the telecommunication range, and the computed many-body energy levels suggest a viable optical cycle required for qubit initialization. Notably, the high-spin nucleus of each dopant strongly couples to the electron spin, leading to many controllable quantum levels and the emergence of atomic clock-like transitions that are well protected from environmental noise. Specifically, the Hanh-echo coherence time increases beyond seconds at the clock-like transition in the defect with 209 Bi. Our results pave the way to designing quantum states with long coherence times in simple oxides, making them attractive platforms for quantum technologies.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2025

Global terrestrial nitrogen fixation and its modification by agriculture

Biological nitrogen fixation (BNF) is the largest natural source of new nitrogen (N) that supports terrestrial productivity, yet estimates of global terrestrial BNF remain highly uncertain. Here, in this study, we show that this uncertainty is partly because of sampling bias, as field BNF measurements in natural terrestrial ecosystems occur where N fixers are 17 times more prevalent than their mean abundances worldwide. To correct this bias, we develop new estimates of global terrestrial BNF by upscaling field BNF measurements using spatially explicit abundances of all major biogeochemical N-fixing niches. We find that natural biomes sustain lower BNF, 65 (52–77) Tg N yr −1 , than previous empirical bottom-up estimates, with most BNF occurring in tropical forests and drylands. We also find high agricultural BNF in croplands and cultivated pastures, 56 (54–58) Tg N yr −1 . Agricultural BNF has increased terrestrial BNF by 64% and total terrestrial N inputs from all sources by 60% over pre-industrial levels. Our results indicate that BNF may impose stronger constraints on the carbon sink in natural terrestrial biomes and represent a larger source of agricultural N than is generally considered in analyses of the global N cycle, with implications for proposed safe operating limits for N use.

Reis Ely, Carla R. [Oregon State Univ., Corvallis,↗
DOE OSTI2015

Radionuclide gas transport through nuclear explosion-generated fracture networks

Underground nuclear weapon testing produces radionuclide gases which may seep to the surface. Barometric pumping of gas through explosion-fractured rock is investigated using a new sequentially-coupled hydrodynamic rock damage/gas transport model. Fracture networks are produced for two rock types (granite and tuff) and three depths of burial. The fracture networks are integrated into a flow and transport numerical model driven by surface pressure signals of differing amplitude and variability. There are major differences between predictions using a realistic fracture network and prior results that used a simplified geometry. Matrix porosity and maximum fracture aperture have the greatest impact on gas breakthrough time and window of opportunity for detection, with different effects between granite and tuff simulations highlighting the importance of accurately simulating the fracture network. In particular, maximum fracture aperture has an opposite effect on tuff and granite, due to different damage patterns and their effect on the barometric pumping process. From stochastic simulations using randomly generated hydrogeologic parameters, normalized detection curves are presented to show differences in optimal sampling time for granite and tuff simulations. In conclusion, seasonal and location-based effects on breakthrough, which occur due to differences in barometric forcing, are stronger where the barometric signal is highly variable.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2015

Review of disaster management implementation for the community safety in the vicinity of oil and gas field

Sukowati site which is operated by Production Sharing Contract (PSC) Joint Operating Body Pertamina Petrochina East Java (JOB P-PEJ) located at Bojonegoro regency East Java Province. This site is close to densely populated settlements with approximately 6,010 people within a radius less than 600 m. The fluid produced have a dangerous potential to the above mention community, due to accompanying of hydrogen sulphide gas (H2S) with a concentration about 0.6% – 2% from the total gas produced. In 2006, there was incident of gas leak from drilling development well of Sukowati # 5. The incident made the surrounding community panic due to lack of preparedness and awareness. Learning from the incident, the company together with the government and local communities initiated to make improvements through the disaster management system approach. The efforts are carried out in accordance with the 4 (four) periods in a continuous cycle consist of (1) mitigation; (2) preparation; (3) response and (4) recovery. Emergency response drills conducted regularly at least once a year, its main purpose is to find out the results of the implementation of the existing disaster management. The results of the drills showed an increase in public awareness and responsiveness to emergency situations caused by the operational failures of oil and gas exploration and production activities near their settlement.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2015

Turning nuclear waste into glass

Vitrification has emerged as the treatment option of choice for the most dangerous radioactive waste. But dealing with the nuclear waste legacy of the Cold War will require state-of-the-art facilities and advanced glass formulations.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗