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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 1,567 records · Page 87
All sourcesNASA NTRSDOE OSTI
DOE OSTI2018

LncRNA LINC00319 accelerates ovarian cancer progression through miR-423-5p/NACC1 pathway

Highlights: • LINC00319 is upregulated in ovarian cancer. • LINC00319 promotes ovarian cancer proliferation, migration and invasion. • LINC00319 promotes NACC1 expression by interacting with miR-423-5p. • LINC00319 promotes ovarian cancer progression relying on miR-423-5p/NACC1 pathway. Long noncoding RNA (lncRNA) LINC00319 has been reported to promote carcinogenesis of lung cancer and cutaneous squamous cell carcinoma. However, the role and mechanism of LINC00319 in ovarian cancer progression is unclear. In this study, LINC00319 expression was found to be upregulated in ovarian cancer tissues and cell lines. And our evidence showed that LINC00319 could be a potential prognostic biomarker for patients with ovarian cancer. Cell Counting Kit-8 (CCK-8), colony formation and transwell assays indicated that LINC00319 upregulation promoted proliferation, migration and invasion of ovarian cancer cells. Bioinformatics analysis and luciferase reporter assay revealed that LINC00319 worked as the sponge for miR-423-5p. Furthermore, miR-423-5p directly targeted NACC1. qRT-PCR and western blot results demonstrated that LINC00319 upregulates NACC1 expression through inhibiting miR-423-5p in ovarian cancer cells. Moreover, we observed an inverse expression correlation between miR-423-5p and LINC00319 or between miR-423-5p and NACC1 in ovarian cancer tissues. Finally, rescue assay showed that NACC1 restoration rescued the potentials of proliferation, migration and invasion in LINC00319-depleted ovarian cancer cells. In conclusion, our findings demonstrated that LINC00319 promotes ovarian cancer progression through upregulating NACC1 expression by restraining miR-423-5p.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2018

Syk and JNK signaling pathways are involved in inflammasome activation in macrophages infected with Streptococcus pneumoniae

Highlights: • Syk- and JNK-dependent ASC oligomerization is crucial for inflammasome assembling during S. pneumoniae infection. • PLY participates in phosphorylation and activation of Syk and JNK in S. pneumoniae-infected macrophages. • Syk may be involved in JNK phosphorylation in S. pneumoniae infection. Streptococcus pneumoniae is a pathogen of significant clinical importance worldwide that can cause severe invasive diseases, such as pneumonia, otitis media and meningitis. Inflammsomes has been reported to participate in host defense against S. pneumoniae infection. S. pneumoniae could induce the assembly of the nucleotide-binding oligomerization domain-like receptor family pyrin domain containing 3 (NLRP3)/absent in melanoma 2 (AIM2) inflammasome, which mediates the activation of caspase-1 and the subsequent maturation of Interleukin-1β (IL-1β). However, the precise signals that activate inflammasomes during pneumococcal infection remain to be fully elucidated. In the present study, primary mouse macrophages were selected as a cell model, and the effects of kinases on inflammasome activity induced by S. pneumoniae infection were examined by ELISA and western blotting after pretreatment with a kinase inhibitor. Here, we show that Syk and JNK signaling are required for S. pneumoniae-induced activation of the inflammasome. Inhibitors of Syk and JNK almost abolished the oligomerization of apoptosis-associated speck-like protein containing a caspase-activating and recruitment domain (ASC) and subsequent caspase-1 activation and IL-1β secretion. Moreover, pneumolysin (PLY) participated in this process and was critical for Syk/JNK activation. These results suggested that the Syk/JNK signaling pathway may play a vital role in the inflammasome activation and modulate host immune responses against S. pneumoniae.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2018

Klotho prevents DEX-induced apoptosis in MC3T3-E1 osteoblasts through the NF-κB signaling pathway

Highlights: • Klotho can inhibit DEX-induced apoptosis of MC3T3-E1 osteoblasts by inhibiting the expression of caspase-3. • NF-κB inhibitor PDTC reduced the number of DEX-induced apoptotic cells and attenuated the activity of caspase-3. • Klotho can inhibit IκB degradation, NF-κB nuclear translocation, and p65 phosphorylation in DEX-induced MC3T3-E1 apoptosis. Dexamethasone (DEX) is a commonly used anti-inflammatory drug and an immunosuppressive drug used in clinical practice to treat a variety of diseases. Glucocorticoid-induced osteoporosis (GIOP) is a consequence of high dose, or a long-term low dose use of glucocorticoids (GCs). These treatment regimens can cause a variety of bone-related adverse effects, leading to increased osteoblast and bone cell apoptosis. Evidence suggests that klotho (KL) can inhibit GIOP. It is unknown whether KL attenuates DEX-induced apoptosis in MC3T3-E1 cells or the underlying mechanisms involved. In the present study, we found that MC3T3-E1 cells pretreated with DEX led to the up-regulation of cleaved-caspase-3, and down-regulation of caspase-3, which were inhibited by KL transfection. Furthermore, flow cytometry and western blot analysis revealed that the NFκB inhibitor pyrrolidine dithiocarbamate (PDTC) could restore the DEX-induced caspase-3 decrease and inhibit the DEX-induced cleaved caspase-3 increase. We observed that DEX stimulated the degradation of IκBα(NFκB inhibitor α) and the translocation of NFκB, which were suppressed by KL transfection. These findings therefore, indicate a protective role for KL against osteoblastic cell apoptosis induced by DEX, via the NF-κB signaling pathway.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2018

Hydrogen sulfide ameliorated lipopolysaccharide-induced acute lung injury by inhibiting autophagy through PI3K/Akt/mTOR pathway in mice

Highlights: • Autophagy activation is an important pathogenesis of LPS-induced ALI in mouse. • H{sub 2}S can inhibit the activation of autophagy in ALI induced by LPS. • H{sub 2}S and 3-MA ameliorated LPS-induced ALI both in vivo and in vitro. • H{sub 2}S inhibit the activation of autophagy through PI3K/Akt/mTOR pathway. Recent studies reported that hydrogen sulfide (H{sub 2}S) is an effective agent for the prevention and treatment of acute lung injury (ALI). But the underlying mechanisms have not been understood clearly. In this study, we explored the possible mechanism from the perspective of autophagy regulation.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2021

Global Biodiversity Implications of Alternative Electrification Strategies Under the Shared Socioeconomic Pathways

Addressing climate mitigation while meeting global electrification goals will require major transitions from fossil-fuel dependence to large-scale renewable energy deployment. However, renewables require significant land assets per unit energy and could come at high cost to ecosystems, creating potential conflicts between global climate mitigation and biodiversity conservation. Here, we explore the potential biodiversity implications of alternative future global electrification pathways as depicted under the Shared Socioeconomic Scenarios (SSPs), i.e., alternative trends in societal development. We examined the intersection of high-resolution estimates of global energy densities for ten renewable and conventional technologies with global richness data to estimate technology-specific biodiversity footprints (species per GWh), whereas a Cumulative Biodiversity Impact (CBI) score was used to assess land and biodiversity outcomes of alternative scenarios. Downscaled electricity generation scenarios (2020-2100) were also constrained by alternative land conservation and energy development policies. Unexpectedly, variation among SSPs did not exhibit a clear tradeoff between global climate mitigation and CBI. Rather, CBIs were an outcome of total infrastructure development to meet electricity demand (from population growth and GDP) and the total magnitude of renewable energy development and storage technologies. Renewables assembled along a spectrum from land sharing to sparing. At the land sharing end, biomass-powered electricity from dedicated crops contributed the most to biodiversity impacts due to low energy density, whereas land-sparing technologies (solar) caused more-intense land degradation, but in smaller areas. Our results suggest that local land conservation practices and strategies promoting energy diversification could have greater implications for future biodiversity conflicts than global socioeconomic drivers.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2025

Multi-objective optimization of sustainable aviation fuel production pathways in the U.S. Corn Belt

As a potential source of low-carbon transportation energy, biofuels offer certain advantages over vehicle electrification (e.g., lower societal vulnerability to grid failures, and improved range of sustainable aviation), but also several challenges, including cost, carbon intensity, and land usage. There are also well-founded concerns that biofuel supply chains could be disrupted if extreme weather events impact feedstock yields. In this paper, we explore the use of multi-objective optimization to identify biofuel production pathways that balance cost, greenhouse gas emissions, and supply vulnerability to extreme weather. We compare the use of three different many-objective evolutionary algorithms and linear programming in optimizing biomass cultivation decisions in the U.S. Corn Belt under weather uncertainty using historical, modeled, and synthetic yield data. We consider four feedstock choices (corn, soy, switchgrass, and algae) with two land types (agricultural and marginal lands) and evaluate decisions using three alternative spatial resolutions (ranging from the USDA agricultural district level to the state level). Results show that feedstock choice is the primary driver of objective performance (i.e., the position and shape of 3D, approximate Pareto frontiers). Spatial diversification is a less effective tool in reducing exposure to weather-caused drops in crop yield.

09 BIOMASS FUELS↗
DOE OSTI2024

Multiomic Network Analysis Identifies Dysregulated Neurobiological Pathways in Opioid Addiction

BACKGROUND: Opioid addiction is a worldwide public health crisis. In the United States, for example, opioids cause more drug overdose deaths than any other substance. However, opioid addiction treatments have limited efficacy, meaning that additional treatments are needed. METHODS: To help address this problem, we used network-based machine learning techniques to integrate results from genome-wide association studies of opioid use disorder and problematic prescription opioid misuse with transcriptomic, proteomic, and epigenetic data from the dorsolateral prefrontal cortex of people who died of opioid overdose and control individuals. RESULTS: Here we identified 211 highly interrelated genes identified by genome-wide association studies or dysregulation in the dorsolateral prefrontal cortex of people who died of opioid overdose that implicated the Akt, BDNF (brain-derived neurotrophic factor), and ERK (extracellular signal-regulated kinase) pathways, identifying 414 drugs targeting 48 of these opioid addiction–associated genes. Some of the identified drugs are approved to treat other substance use disorders or depression. CONCLUSIONS: Our synthesis of multiomics using a systems biology approach revealed key gene targets that could contribute to drug repurposing, genetics-informed addiction treatment, and future discovery.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2022

Machine learning for surrogate process models of bioproduction pathways

Technoeconomic analysis and life-cycle assessment are critical to guiding and prioritizing bench-scale experiments and to evaluating economic and environmental performance of biofuel or biochemical production processes at scale. Traditionally, commercial process simulation tools have been used to develop detailed models for these purposes. However, developing and running such models can be costly and computationally intensive, which limits the degree to which they can be shared and reproduced in the broader research community. This study evaluates the potential of an automated machine learning approach to develop surrogate models based on conventional process simulation models. The analysis focuses on several high-value biofuels and bioproducts for which pathways of production from biomass feedstocks have been well-established. The results demonstrate that surrogate models can be an accurate and effective tool for approximating the cost, mass and energy balance outputs of more complex process simulations at a fraction of the computational expense.

09 BIOMASS FUELS↗
DOE OSTI2023

Intra-catalyst CH 4 oxidation pathways on a Pd/Al 2 O 3 /CeZrO x -based commercial catalyst and implications on NO x conversion profiles for a natural gas vehicle exhaust under lambda modulation

The performance of a three-way catalyst (TWC) in natural gas-powered vehicles is enhanced by periodic changes in air-to-fuel ratio (λ-modulation). The reaction networks and sequences inside the catalyst that facilitate such enhanced performance have not been extensively investigated. Here, this work applied intra-catalyst measurements (SpaciMS) to analyze the transient spatiotemporal gas concentrations inside a Pd-based TWC to establish relationships between CH 4 , NO x , CO and H 2 conversion pathways. Steam reforming and partial oxidation were revealed to be the main CH 4 conversion routes. The cyclic rich-lean conditions combined with the oxygen storage capacity (OSC) of the TWC generate reduced and oxidized zones that are constantly moving within the catalyst, changing the dominant chemical reactions occurring on the surface. In the reduced zones, OSC is depleted while CH 4 is converted through steam reforming and NO x is converted through reactions with H 2 , CO, and other surface-bound reducing fragments formed by CH 4 conversion. In the oxidized zones, OSC is replenished, CH 4 is converted by partial oxidation, and H 2 , CO, and NH 3 are oxidized. The length of lean-rich phases impacts the catalyst performance significantly; too short or too long of a rich or lean phase can lower the overall conversion of reactive species. An inhibition of CH 4 conversion was observed during the rich phase possibly due to CO-poisoning of active sites. The intra-catalyst measurements revealed that the catalyst consists of three distinct reaction zones and their lengths vary with modulation conditions. Various modulation frequencies, amplitudes, λ-centers, and temperatures were investigated which allowed an understanding of how these parameters affect the reaction zones and catalyst utilization. Understandings from this work can enable adaptive λ-control strategies to optimize the overall TWC performance over a range of vehicle operating conditions.

Lean-Rich cycling↗
DOE OSTI2026

Comparative life-cycle assessments and techno-economic analysis of renewable natural gas production pathways from biogas

Renewable natural gas (RNG) offers a promising pathway for decarbonizing hard-to-abate sectors. This study shows that, relative to conventional upgrading technologies (i.e., membrane separation and pressure swing adsorption), the catalytic methanation reaction (CMR) at water resource recovery facilities doubles RNG output. When consuming lowcarbon hydrogen, the CMR reduces operational energy use and global warming potential. Techno-economic analysis indicates that the CMR is not yet competitive but will become viable if hydrogen reaches $1/kg. Heat integration and hydrogen cost are key drivers of overall performance.

03 NATURAL GAS↗
DOE OSTI2017

Pressure dependent kinetic analysis of pathways to naphthalene from cyclopentadienyl recombination

Cyclopentadiene (CPD) and cyclopentadienyl radical (CPDyl) reactions are known to provide fast routes to naphthalene and other polycyclic aromatic hydrocarbon (PAH) precursors in many systems. In this work, we combine literature quantum chemical pathways for the CPDyl + CPDyl recombination reaction and provide pressure dependent rate coefficient calculations and analysis. Here we find that the simplified 1-step global reaction leading to naphthalene and two H atoms used in many kinetic models is not an adequate description of this chemistry at conditions of relevance to pyrolysis and steam cracking. The C 10 H 10 species is observed to live long enough to undergo H abstraction reactions to enter the C 10 H 9 potential energy surface (PES). Rate coefficient expressions as functions of T and P are reported in CHEMKIN format for future use in kinetic modeling.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2024

Pathways to formulate lightweight and ultra-lightweight 3D printable cementitious composites

Here, this paper studies the pathways to formulate lightweight and ultra-lightweight 3D printable cementitious composites. A hybrid approach was proposed by combining the advantages of traditional chemical-induced foaming (foaming approach) and lightweight particulate inclusions (synthetic foam approach). A comprehensive experimental program was conducted to evaluate the effects of foaming agents and fly ash cenosphere (FAC) on the printability, microstructure, mechanical and thermal properties of 3D printed samples. The results showed that the hybrid approach could produce a mixture with a density as low as 470 kg/m 3 while ensuring good flowability and buildability owing to the lubricating effect of foaming and supporting skeleton formed by FAC. In addition, a three-step homogenization procedure was also developed to predict the effective elastic modulus and thermal conductivity of 3D printable cementitious composites and cementitious foam. The findings of the study highlighted the effectiveness of the hybrid approach in formulating 3D printable ultra-lightweight cementitious composites in thermal insulation and acoustic applications.

36 MATERIALS SCIENCE↗
DOE OSTI2017

Leveraging microbial biosynthetic pathways for the generation of ‘drop-in’ biofuels

Advances in retooling microorganisms have enabled bioproduction of ‘drop-in’ biofuels, fuels that are compatible with existing spark-ignition, compression-ignition, and gasturbine engines. As the majority of petroleum consumption in the United States consists of gasoline (47%), diesel fuel and heating oil (21%), and jet fuel (8%), ‘drop-in’ biofuels that replace these petrochemical sources are particularly attractive. In this review, we discuss the application of aldehyde decarbonylases to produce gasoline substitutes from fatty acid products, a recently crystallized reductase that could hydrogenate jet fuel precursors from terpene synthases, and the exquisite control of polyketide synthases to produce biofuels with desired physical properties (e.g., lower freezing points). With our increased understanding of biosynthetic logic of metabolic pathways, we discuss the unique advantages of fatty acid, terpene, and polyketide synthases for the production of bio-based gasoline, diesel and jet fuel.

09 BIOMASS FUELS↗
DOE OSTI2022

Photoionization energetics and dissociation pathways of hydroperoxyethyl formate produced in the reaction of CH 3 CHOO + formic acid

The bimolecular reaction of Criegee intermediates, zwitterionic carbonyl oxide species produced in alkene ozonolysis, with organic acids leads to formation of functional hydroperoxides implicated in the generation of atmospheric aerosols. This theoretical study using high-level explicitly correlated coupled-cluster theory examines the low energy conformers of hydroperoxyethyl formate [HOOCH(CH 3 )OCHO, HPEF] formed in the bimolecular reaction of CH 3 CHOO, a simple alkyl-substituted Criegee intermediate, with formic acid, and the detection of HPEF via photoionization. Here, the vertical and adiabatic ionization energies of HPEF are computed, along with the pathways for dissociative ionization that produce HO 2 or OCHO fragments with daughter ions.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2020

Health co-benefits and mitigation costs as per the Paris Agreement under different technological pathways for energy supply

This study assesses the reductions in air pollution emissions and subsequent beneficial health effects from different global mitigation pathways consistent with the 2 °C stabilization objective of the Paris Agreement. We use an integrated modelling framework, demonstrating the need for models with an appropriate level of technology detail for an accurate co-benefit assessment. The framework combines an integrated assessment model (GCAM) with an air quality model (TM5-FASST) to obtain estimates of premature mortality and then assesses their economic cost. The results show that significant co-benefits can be found for a range of technological options, such as introducing a limitation on bioenergy, carbon capture and storage (CCS) or nuclear power. Cumulative premature mortality may be reduced by 17–23% by 2020–2050 compared to the baseline, depending on the scenarios. However, the ratio of health co-benefits to mitigation costs varies substantially, ranging from 1.45 when a bioenergy limitation is set to 2.19 when all technologies are available. As for regional disaggregation, some regions, such as India and China, obtain far greater co-benefits than others.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2020

Defining pathways to healthy sustainable urban development

Goals and pathways to achieve sustainable urban development have multiple interlinkages with human health and wellbeing. However, these interlinkages have not been examined in depth in recent discussions on urban sustainability and global urban science. This paper fills that gap by elaborating in detail the multiple links between urban sustainability and human health and by mapping research gaps at the interface of health and urban sustainability sciences. As researchers from a broad range of disciplines, we aimed to: 1) define the process of urbanization, highlighting distinctions from related concepts to support improved conceptual rigour in health research; 2) review the evidence linking health with urbanization, urbanicity, and cities and identify cross-cutting issues; and 3) highlight new research approaches needed to study complex urban systems and their links with health. This novel, comprehensive knowledge synthesis addresses issue of interest across multiple disciplines. Our review of concepts of urban development should be of particular value to researchers and practitioners in the health sciences, while our review of the links between urban environments and health should be of particular interest to those outside of public health. We identify specific actions to promote health through sustainable urban development that leaves no one behind, including: integrated planning; evidence-informed policy-making; and monitoring the implementation of policies. We also highlight the critical role of effective governance and equity-driven planning in progress towards sustainable, healthy, and just urban development.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2018

Pathways linking residential noise and air pollution to mental ill-health in young adults

Highlights: • A model with multiple pathways was tested. • Daytime noise was related to poor mental health. • Air pollution had only an indirect effect. • Key mediators: annoyance and neighborhood restorative quality. Recent years have seen growing, but still tentative, evidence of the potential associations of environmental noise and air pollution with mental disorders. In the present study, we aimed to examine the associations between residential noise and air pollution exposures and general mental health in young adults with a focus on underlying processes.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2023

Exploring sustainable electricity system development pathways in South America’s MERCOSUR sub-region

South America has abundant natural water and energy resources, and exploiting these resources to achieve a clean energy future is central to the continent’s economic and sustainable development objectives for the next several decades. Designing pathways to achieving this clean energy future requires better understanding the structural, techno-economic, and policy forces that may influence the future development of the electricity sector in the region. Here, we focus on an interconnected electricity system of five South American countries – Argentina, Brazil, Chile, Paraguay, and Uruguay – which represent major electricity generation, consumption, and trade dynamics in the region. We explore the implications of various forces that could shape the future composition of the power sector in the sub-region, including: evolving renewable energy cost and performance, natural gas prices, cross-border interconnection facilities, early retirement of installed hydropower, and different decarbonization goals. We use a model framework based on a power system planning platform (GridPath) to co-optimize investment and operations of generation, storage, and transmission facilities out to 2050. Our results in a Reference scenario indicate that the electricity system can maintain a relatively clean energy portfolio by leveraging existing hydropower capacity and integrating increasingly cost-competitive wind and solar power. However, dependence on natural gas in the region is likely to remain high. A low-carbon electricity system can cost-effectively be achieved through policy interventions (e.g., renewable portfolio standards) and by diversifying investments in wind, solar, battery storage, and some new hydropower capacity. We also find that existing hydropower is critical for maintaining reliable future grid operations. Enhanced regional electricity trade, mostly based on existing interconnection capacities with nominal investment in new transmission, can significantly benefit the clean energy transition in the region.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗