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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 289 records · Page 16
All sourcesNASA NTRSDOE OSTI
DOE OSTI2022

Citrus FRIGIDA cooperates with its interaction partner dehydrin to regulate drought tolerance

SUMMARY Drought is a major environmental stress that severely affects plant growth and crop productivity. FRIGIDA ( FRI ) is a key regulator of flowering time and drought tolerance in model plants. However, little is known regarding its functions in woody plants, including citrus. Thus, we explored the functional role of the citrus FRI ortholog ( CiFRI ) under drought. Drought treatment induced CiFRI expression. CiFRI overexpression enhanced drought tolerance in transgenic Arabidopsis and citrus, while CiFRI suppression increased drought susceptibility in citrus. Moreover, transcriptomic profiling under drought conditions suggested that CiFRI overexpression altered the expression of numerous genes involved in the stress response, hormone biosynthesis, and signal transduction. Mechanistic studies revealed that citrus dehydrin likely protects CiFRI from stress‐induced degradation, thereby enhancing plant drought tolerance. In addition, a citrus brassinazole‐resistant (BZR) transcription factor family member ( CiBZR1 ) directly binds to the CiFRI promoter to activate its expression under drought conditions. CiBZR1 also enhanced drought tolerance in transgenic Arabidopsis and citrus. These findings further our understanding of the molecular mechanisms underlying the CiFRI ‐mediated drought stress response in citrus.

Xu, Yuan‐Yuan↗
NASA NTRS1988

Implementing the Provisions of the National Environmental Policy Act

This handbook provides guidance and assistance to NASA officials in carrying out their responsibilities under the National Environmental Policy Act and the applicable NASA procedures (14 CFR 1216.3, Attachment A to NMI 8800.7). The handbook, as was contemplated by the regulations of the Council on Environmental Quality, stresses the need for environmental analysis from the time of early planning through environmental assessment and environmental impact statement preparation to implementation of the subject action, and provides for necessary follow up. It stresses the need for NASA officials to draw upon all the appropriate disciplines from the natural and social sciences plus the environmental design arts in planning and decision making on actions which may have an impact on the human environment. The handbook is applicable to NASA Headquarters and field installations.

Source record↗
DOE OSTI2020

Los Alamos National Laboratory Hazardous Waste Facility Permit Community Relations Plan

The requirements of the Hazardous Waste Facility Permit are fulfilled through execution of LANL's fourth strategic goal: “Enabling mission delivery through next-generation facility, infrastructure, and operational excellence.” With input from our stakeholders, we will continue to fulfill those requirements and to improve our waste operations. In 2015, the Laboratory purpose statement focused waste management efforts by directing delivery of mission success through operational effectiveness and scientific excellence. This Plan advances that purpose through community involvement. In the process of achieving our national security mission, Los Alamos National Laboratory generates some hazardous and mixed waste. Hazardous waste is solid waste that is dangerous or potentially harmful to human health or the environment. Hazardous wastes can be liquids, solids, gases, or sludges. They can be discarded as commercial products, such as cleaning fluids or pesticides, or as the byproducts of operations. Specific substances are listed in 40 Code of Federal Regulations (CFR), Part 261: 40 CFR Part 261. Hazardous waste management activities are regulated by the U. S. Environmental Protection Agency and the New Mexico Environment Department (NMED) pursuant to New Mexico Hazardous Waste Act (HWA; Chapter 74, Article 4 NMSA 1978) and regulations under the Act. In 1989, NMED issued the Hazardous Waste Facility Permit (EPA ID Number NM0890010515-1) that established standards for the Laboratory to manage, store, and treat hazardous wastes on-site and to undertake the closure, post closure care, and cleanup as necessary, of permitted waste management units. On November 30, 2010, NMED renewed the Hazardous Waste Facility Permit (the Permit). In June 2020 the Permittees submitted a permit renewal application to the NMED for their review and approval. The Hazardous Waste Facility Permit Community Relations Plan (CRP) describes the scope of public involvement in the activities of the Permit. The CRP is specifically designed to facilitate the community outreach, engagement, and relations activities concerning the Laboratory’s Hazardous Waste Facility Permit and coordinates with but does not include public involvement for other Laboratory programs, initiatives, or environmental activities.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2022

The regulation of the cell wall by glycosylphosphatidylinositol-anchored proteins in Arabidopsis

A polysaccharides-based cell wall covers the plant cell, shaping it and protecting it from the harsh environment. Cellulose microfibrils constitute the cell wall backbone and are embedded in a matrix of pectic and hemicellulosic polysaccharides and glycoproteins. Various environmental and developmental cues can regulate the plant cell wall, and diverse glycosylphosphatidylinositol (GPI)-anchored proteins participate in these regulations. GPI is a common lipid modification on eukaryotic proteins, which covalently tethers the proteins to the membrane lipid bilayer. Catalyzed by a series of enzymic complexes, protein precursors are post-translationally modified at their hydrophobic carboxyl-terminus in the endomembrane system and anchored to the lipid bilayer through an oligosaccharidic GPI modification. Ultimately, mature proteins reach the plasma membrane via the secretory pathway facing toward the apoplast and cell wall in plants. In Arabidopsis, more than three hundred GPI-anchored proteins (GPI-APs) have been predicted, and many are reported to be involved in diverse regulations of the cell wall. In this review, we summarize GPI-APs involved in cell wall regulation. GPI-APs are proposed to act as structural components of the cell wall, organize cellulose microfibrils at the cell surface, and during cell wall integrity signaling transduction. Besides regulating protein trafficking, the GPI modification is potentially governed by a GPI shedding system that cleaves and releases the GPI-anchored proteins from the plasma membrane into the cell wall.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2023

Seasonality regulates the structure and biogeochemical impact of ectomycorrhizal fungal communities across environmentally divergent neotropical dry forests

Abstract Ectomycorrhizal (ECM) symbioses support forest functioning globally, yet both the structure and function of ECM fungal communities in seasonally dry neotropical forests (SDTFs), known for extreme heterogeneity in vegetation and edaphic properties, remain under characterized. Here, we evaluated the relative influences of seasonal versus spatial variation in ECM fungal community structure in soils from four environmentally divergent SDTFs. We also assessed the importance of biotic and abiotic drivers of SDTF ECM fungal community structure at regional scales, as well as ECM impacts on soil carbon (C) and nitrogen (N) cycling. ECM fungal frequency, relative abundance and richness all increased in the wet season, but spatial rather than seasonal effects explained more variation in community composition. Across the four SDTFs investigated, differences in tree communities drove ECM fungal community turnover more than geographic distances, site abiotic conditions or soil chemistry. Although soil moisture and ECM tree basal area were stronger predictors of soil biogeochemistry, incorporating ECM fungal community composition and relative abundance added explanatory power to models of soil C and N cycling in the wet season. Synthesis : Our results highlight the importance of seasonality and plant community composition in shaping different aspects of SDTF ECM fungal community structure and diversity as well as the potential for both the plant and fungal components of ECM symbioses to impact soil functioning across heterogenous SDTFs. Furthermore, our findings suggest that alterations in SDTF plant community composition due to climate or land‐use change will have important consequences for ECM fungal diversity and associated effects on soil biogeochemical cycling.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2025

Past Approaches for Spent Nuclear Fuel, High-Level, and Transuranic Waste Disposal in the United States—Part 1: Safety Criteria and Treatment of Uncertainty

The United States (US), with its 50-year experience in developing deep geologic disposal for transuranic waste, spent nuclear fuel (SNF), and high-level radioactive waste (HLW), has much to share with other countries. Yet, other countries are better able to translate the US experience and corresponding policy decisions into solutions sensible for their country when they understand the compliance requirements in US laws and regulations. This paper presents past approaches in the generic and site-specific standards of the US Environmental Protection Agency (EPA) and implementing regulations of the US Nuclear Regulatory Commission (NRC) using the framework provided by (1) key questions of the Blue Ribbon Commission on America’s Nuclear Future, and (2) international consensus standards. Both the 1985 EPA generic standards, as updated in 1993 and applied at the operating Waste Isolation Pilot Plant in southern New Mexico for transuranic waste from atomic energy defense activities, and the EPA 2008 site-specific standards and implementing regulations, as applied at the proposed Yucca Mountain repository in southern Nevada for SNF and HLW, adopt the strategy of using quantitative, probabilistic analysis to assess performance and compliance.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
NASA NTRS2011

Molecular Mechanisms of Circadian Regulation During Spaceflight

Disruption of the regular environmental circadian cues in addition to stringent and demanding operational schedules are two main factors that undoubtedly impact sleep patterns and vigilant performance in the astronaut crews during spaceflight. Most research is focused on the behavioral aspects of the risk of circadian desynchronization, characterized by fatigue and health and performance decrement. A common countermeasure for circadian re-entrainment utilizes blue-green light to entrain the circadian clock and mitigate this risk. However, an effective countermeasure targeting the photoreceptor system requires that the basic circadian molecular machinery remains intact during spaceflight. The molecular clock consists of sets of proteins that perform different functions within the clock machinery: circadian oscillators (genes whose expression levels cycle during the day, keep the pass of cellular time and regulate downstream effector genes), the effector or output genes (those which impact the physiology of the tissue or organism), and the input genes (responsible for sensing the environmental cues that allow circadian entrainment). The main environmental cue is light. As opposed to the known photoreceptors (rods and cones), the non-visual light stimulus is received by a subset of the population of retinal ganglion cells called intrinsically photosensitive retinal ganglion cells (ipRGC) that express melanopsin (opsin 4 -Opn4-) as the photoreceptor. We hypothesize that spaceflight may affect ipRGC and melanopsin expression, which may be a contributing cause of circadian disruption during spaceflight. To answer this question, eyes from albino Balb/cJ mice aboard STS-133 were collected for histological analysis and gene expression profiling of the retina at 1 and 7 days after landing. Both vivarium and AEM (animal enclosure module) mice were used as ground controls. Opn4 expression was analyzed by real time RT/qPCR and retinal sections were stained for Opn4 immunofluorescence. Opn4 was decreased (abrogated in one case) in retinas that concurrently showed higher evidence of oxidative stress. We propose that oxidative stress can lead to a decrease in melanopsin expression, likely via ipRGC loss or impairment, and thus, it can be a contributing factor to circadian disruption during spaceflight. Countermeasures contemplating the use of light should therefore be complemented with melanopsin expression maintenance and/or reduction in oxidative stress.

Zanello, Susana↗
DOE OSTI2021

Conditional filamentation as an adaptive trait of bacteria and its ecological significance in soils

Bacteria can regulate cell morphology in response to environmental conditions, altering their physiological and metabolic characteristics to improve survival. Conditional filamentation, in which cells suspend division while continuing lateral growth, is a strategy with a range of adaptive benefits. Here, we review the causes and consequences of conditional filamentation with respect to bacterial physiology, ecology and evolution. We describe four major benefits from conditional filamentation: stress tolerance, surface colonization, gradient spanning and the facilitation of biotic interactions. Adopting a filamentous growth habit involves fitness trade-offs which are also examined. We focus on the role of conditional filamentation in soil habitats, where filamentous morphotypes are highly prevalent and where environmental heterogeneity can benefit a conditional response. Here, to illustrate the use of information presented in our review, we tested the conditions regulating filamentation by the forest soil isolate Paraburkholderia elongata 5N T . Filamentation by P. elongata was induced at elevated phosphate concentrations, and was associated with the accumulation of intracellular polyphosphate, highlighting the role of filamentation in a phosphate-solubilizing bacterium. Conditional filamentation enables bacteria to optimize their growth and metabolism in environments that are highly variable, a trait that can impact succession, symbioses, and biogeochemistry in soil environments.

59 BASIC BIOLOGICAL SCIENCES↗
NASA NTRS2008

Program Environmental Assurance: Shuttle Environmental Assurance and the Future

Material availability continues to be impacted by domestic and international environmental health and safety (EH&S) regulations, industrial pollution prevention goals and related vendor economics. SEA is an integrated team that works to identify, communicate and address safety and environmentally driven materials obsolescence issues and pollution prevention opportunities.

Glover, Steve E.↗
DOE OSTI2023

2020 Postclosure Groundwater Monitoring and Inspection Report, Central Nevada Test Area, Subsurface Corrective Action Unit 443

This report presents the groundwater monitoring data collected by the U.S. Department of Energy (DOE) Office of Legacy Management (LM) from the Central Nevada Test Area (CNTA), Nevada, Site, Subsurface Corrective Action Unit (CAU) 443 in Nye County, Nevada (Figure 1). The CNTA is the site of an underground nuclear test in 1968 that resulted in residual contamination near the detonation depth of 3200 feet (ft); the contamination requires long-term monitoring. Responsibility for the environmental restoration and long-term monitoring was transferred from DOE’s National Nuclear Security Administration, Nevada Field Office, to LM on October 1, 2006. The environmental restoration and site closure process were completed in 2015 in accordance with the amended 1996 Nevada Federal Facility Agreement and Consent Order (FFACO) (State of Nevada et al. 1996, as amended) and all applicable Nevada Division of Environmental Protection (NDEP) policies and regulations. The Closure Report, Central Nevada Test Area, Subsurface Corrective Action, Unit 443 (DOE 2018), also called the Closure Report, originally was completed in January 2016 and revised in October 2018; it describes LM’s plan for long-term postclosure monitoring. This includes monitoring of the radioisotopes of interest and water elevations, inspecting the site and maintaining the institutional controls (ICs), evaluating and reporting data, and documenting the site’s records and data management processes (DOE 2018).

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2020

Long-Term Methane Emissions Rate Quantification and Alert System for Natural Gas Storage Wells and Fields

The Department of Energy (DOE) National Energy Technology Laboratory (NETL) and other critical stakeholders (e.g., U.S. Environmental Protection Agency (USEPA), state regulators, and industry) seek to more accurately characterize and quantify methane emissions from natural gas storage wells. These efforts will reduce uncertainties in estimates of these emissions in USEPA’s current Green House Gas Inventory (GHGI) under their Greenhouse Gas Reporting Program (GHGRP; EPA, 2016). Emission factors currently used to estimate methane emissions from gas storage wells are the same factors used for onshore natural gas production wells (USEPA, 2016). This study has developed a robust and representative dataset of emissions from disaggregated gas station wellhead components and related emission factors that will inform future enhancements to the GHGI and GHGRP. Extensive methane emissions measurements and meteorological data were collected from three active storage facilities representing two of the three types of storage facilities (i.e., depleted gas reservoir and salt cavern) to support development of emissions factors specifically for gas storage wells and associated components. Methane emissions were quantified from both above-ground components (e.g., pipe fittings and valves) and seepage from the ground surface in proximity to gas storage wellheads.

03 NATURAL GAS↗
DOE OSTI2020

Storm Water Pollution Prevention Plan Middle DP Road Recovery Effort, June 26, 2020

The United States Environmental Protection Agency (EPA) has issued a final 2017 Construction General Permit (CGP) that covers discharges of stormwater from construction sites. The 2017 National Pollutant Discharge Elimination System (NPDES) General Permit for Storm Water Discharges from Construction Activity (Appendix D) includes the following requirements:(1) conduct a critical habitat and threatened/endangered species study; (2) develop and implement a Storm Water Pollution Prevention Plan (SWPPP) in accordance with good engineering practices; (3) submit a Notice of Intent (NOI); (4) install and maintain erosion and stormwater controls; (5) perform and document storm water inspections during construction and site stabilization; (6) amend the SWPPP as necessary; and (7) submit a Notice of Termination (NOT) following project completion and final stabilization of disturbed areas. Authorization to discharge storm water is required under this Permit for both large and small construction projects disturbing more than one (1) acre or part of a larger common plan of development that collectively disturbs more than one (1) acre. All parties that meet the definition of Operator must be permitted. Each permittee is not required to develop and implement a separate SWPP Plan. It is required that there be at least one SWPP Plan for a site that incorporates the required elements for all Operators. The 2017 CGP number for New Mexico (Region 6) is NMR100000. This Plan, which has been developed for Triad National Security, LLC (Triad), describes the nature and sequencing of construction activities, potential sources of pollution, and identifies the Best Management Practices (BMPs) to minimize the potential for erosion and storm water pollution. The Plan was developed in accordance with the provisions of the Clean Water Act (33 U.S.C. § §1251 et seq., as amended by the Water Quality Act of 1987, P.L. 100-4), and the regulations established by the U.S. Environmental Protection Agency (EPA) for National Pollutant Discharge Elimination System (NPDES) General Permits for Storm Water Discharges From Construction Activities.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2020

Storm Water Pollution Prevention Plan Middle DP Road Recovery Effort, June 26, 2020 (Copy for Informational Puproses Only)

The United States Environmental Protection Agency (EPA) has issued a final 2017 Construction General Permit (CGP) that covers discharges of stormwater from construction sites. The 2017 National Pollutant Discharge Elimination System (NPDES) General Permit for Storm Water Discharges from Construction Activity (Appendix D) includes the following requirements: (1) conduct a critical habitat and threatened/endangered species study; (2) develop and implement a Storm Water Pollution Prevention Plan (SWPPP) in accordance with good engineering practices; (3) submit a Notice of Intent (NOI); (4) install and maintain erosion and stormwater controls; (5) perform and document storm water inspections during construction and site stabilization; (6) amend the SWPPP as necessary; and (7) submit a Notice of Termination (NOT) following project completion and final stabilization of disturbed areas. Authorization to discharge storm water is required under this Permit for both large and small construction projects disturbing more than one (1) acre or part of a larger common plan of development that collectively disturbs more than one (1) acre. All parties that meet the definition of Operator must be permitted. Each permittee is not required to develop and implement a separate SWPP Plan. It is required that there be at least one SWPP Plan for a site that incorporates the required elements for all Operators. The 2017 CGP number for New Mexico (Region 6) is NMR100000. This Plan, which has been developed for Triad National Security, LLC (Triad), describes the nature and sequencing of construction activities, potential sources of pollution, and identifies the Best Management Practices (BMPs) to minimize the potential for erosion and storm water pollution. The Plan was developed in accordance with the provisions of the Clean Water Act (33 U.S.C. § §1251 et seq., as amended by the Water Quality Act of 1987, P.L. 100-4), and the regulations established by the U.S. Environmental Protection Agency (EPA) for National Pollutant Discharge Elimination System (NPDES) General Permits for Storm Water Discharges From Construction Activities.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2022

Microbial extracellular enzyme activity with simulated climate change

It is critical to understand the consequences of environmental change for the microbial regulation of carbon and nutrient cycling. Specifically, understanding microbial community traits, such as extracellular enzyme activity, can help inform nutrient cycling models and address knowledge gaps. We analyzed data on extracellular enzyme activities and litter decomposition from an 18-month experiment in which microbial communities were reciprocally transplanted along a climate gradient in Southern California. Communities were from desert, scrubland, grassland, pine–oak, and subalpine ecosystems. We aimed to test how enzyme activities responded to climate change following transplantation and how those responses related to decomposition rates. We hypothesized that microbial communities would specialize on their native climate conditions, resulting in higher enzyme activities when transplanted back into their native climate. We investigated the relationship between extracellular enzyme Vmax values, substrate mass loss, and microbial biomass as well as variation in these variables across the climate gradient. We found little evidence for climate specialization, and there was rarely a reduction in enzyme functioning after microbial communities were transplanted into new climate conditions. Moreover, observed differences in decomposition were not related to changes in extracellular enzyme potential, although there were significant differences in enzyme activities and decomposition rates across sites. These results suggest that direct, physiological impacts of climate are likely to be important for enzyme-mediated decomposition, but climate specialization will not constrain the microbial response to climate change in our system.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2025

ER stress and viral defense: Advances and future perspectives on plant unfolded protein response in pathogenesis

Viral infections pose significant threats to crop productivity and agricultural sustainability. The frequency and severity of these infections are increasing, and pathogens are evolving rapidly under the influence of climate change. This underscores the importance of exploring the fundamental mechanisms by which plants defend themselves against dynamic viral threats. One such mechanism is the unfolded protein response (UPR), which is activated when the protein folding demand exceeds the capacity of the endoplasmic reticulum, particularly under adverse environmental conditions. While the key regulators of the UPR in response to viral infections have been identified, our understanding of how they modulate the UPR to suppress plant viral infections at the molecular and genetic levels is still in its infancy. Recent findings have shown that, in response to plant viral infections, the UPR swiftly reprograms transcriptional changes to support cellular, metabolic, and physiological processes associated with cell viability. However, the underlying mechanisms and functional outcomes of these changes remain largely unexplored. Here, we highlight recent advances in plant UPR research and summarize key findings related to viral infection–induced UPR, focusing on the balance between prosurvival and prodeath strategies. We also discuss the potential of systems-level approaches to uncover the full extent of the functional link between the UPR and plant responses to viral infections.

ER stress↗
DOE OSTI2023

Disposition of Solids from Hydrothermal Liquefaction of Biomass: Current Understanding, Research Gaps, and Opportunities

Characteristics of solid residuals generated during hydrothermal liquefaction (HTL) of biomass are reported to establish disposition options for these residuals to reduce liability or barriers to commercialization of HTL. HTL solids from pilot scale are reported and compared to existing HTL solids literature for a variety of biomass feedstocks and HTL configurations, noting differences among literature HTL solids due to solids collection methods. Reported analyses include CHNOS, moisture, ash, inorganics by Inductively Coupled Plasma (ICP), and High Heating Value (HHV). HTL solids are determined to be substantially compatible with U.S. Environmental Protection Agency (EPA) disposal regulations within existing data. Disposition and valorization routes are identified, yet combustion as valorization is determined to be not economically beneficial. Further, research gaps are identified, which include the need for future research to be performed on HTL solids that are representative of a continuous, commercializable flowsheet; verification that specific HTL solids meet EPA disposal requirements; exploration of valorization options; and the need for invention of continuous HTL solids separations/management.

09 BIOMASS FUELS↗
DOE OSTI2025

Geologic hydrogen: a review of resource potential, subsurface dynamics, exploration, production, transportation, and research opportunities

Hydrogen is a versatile resource with critical roles in decarbonization, industrial manufacturing, and energy integration. However, most hydrogen today is produced from fossil fuels, resulting in high emissions and energy consumption. Although low-carbon hydrogen production methods, such as steam methane reforming with carbon capture and renewable-powered electrolysis, are advancing, their high costs hinder large-scale deployment. Identifying alternative pathways for producing low-cost, low-emission hydrogen is therefore essential. Geologic hydrogen, referring to natural and stimulated hydrogen generated in the Earth's subsurface, has attracted growing attention as a potential source of sustainable, economically viable, and environmentally favorable hydrogen. This paper provides a comprehensive review of geologic hydrogen, covering its resource potential, origins, migration and trapping mechanisms, exploration techniques, production strategies, and pipeline transportation. It also identifies key knowledge gaps and proposes a roadmap for future research. The review indicates that geologic hydrogen has vast resource potential and can leverage existing subsurface technologies and geophysical exploration methods. However, major challenges persist, including uncertain hydrogen generation rates, limited understanding and control of serpentinization processes, costly transportation infrastructure, the lack of validated techno-economic analysis, and potential social and environmental issues. As the field is still in its early stages, progress will require interdisciplinary collaboration spanning geoscience, engineering, economics, environmental science, and policy and regulation.

42 ENGINEERING↗
DOE OSTI2022

A model of spatio-temporal regulation within biomaterials using DNA reaction–diffusion waveguides

In multi-cellular organisms, cells and tissues coordinate biochemical signal propagation across length scales spanning micrometres to metres. Designing synthetic materials with similar capacities for coordinated signal propagation could allow these systems to adaptively regulate themselves across space and over time. Here, we combine ideas from cell signalling and electronic circuitry to propose a biochemical waveguide that transmits information in the form of a concentration of a DNA species on a directed path. The waveguide could be seamlessly integrated into a soft material because there is virtually no difference between the chemical or physical properties of the waveguide and the material it is embedded within. We propose the design of DNA strand displacement reactions to construct the system and, using reaction–diffusion models, identify kinetic and diffusive parameters that enable super-diffusive transport of DNA species via autocatalysis. Finally, to support experimental waveguide implementation, we propose a sink reaction and spatially inhomogeneous DNA concentrations that could mitigate the spurious amplification of an autocatalyst within the waveguide, allowing for controlled waveguide triggering. Chemical waveguides could facilitate the design of synthetic biomaterials with distributed sensing machinery integrated throughout their structure and enable coordinated self-regulating programmes triggered by changing environmental conditions.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗