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At least 793 records · Page 44

Real-time patch-clamp sensing of transport across a barrier tissue

The present disclosure relates to methods, apparatuses, and systems to measure one or more electrical signals from a cultured cell layer. In some embodiments, such electrical signals can be indicative of transport or lack of transport of an agent through the cell layer.

Source record↗

Digital-Threat Bias and Psychological Distance: Barriers to Foundational Digital-Security Improvement

Modern life is held together by a web of digital dependencies that enable and provide delivery of critical services and functions—think the provision of utilities such as electricity and water, as well as our dependency on digital services for social and economic services (internet, communication, etc.). As this dependency grows, the complexity related to the delivery of these critical services increases as well. As complexity increases, the understanding of the risk and impact associated with potential disruption, degradation, or destruction—due to either malicious or non-malicious events of those digitally enabled functions—decreases. One potential explanation for the difficulty to 1) understand the risks faced and 2) address them appropriately and effectively is the abstractness and psychological distance assigned to “digital threat.” The complexity of these digitally enabled services creates a perceived complicatedness; as a result, digital threats are treated differently than similarly devasting (but more easily understood) kinetic or physical threats. How we categorize these threats also matters. Acts of cyber-enabled sabotage to critical infrastructure need to be defined as irregular warfare. By inadequately defining the threat, we compound the problem. Acknowledging this digital-threat bias is foundational to improving the ability to protect critical infrastructure. Using construal-level theory and psychological-distance concepts provides an intriguing starting point to address these issues, to reframe the challenges faced, and pursue more effective critical infrastructure security and defense policy.

29 - ENERGY PLANNING, POLICY AND ECONOMY↗

Listening to U.S. Farmers: Barriers and opportunities for growing more biomass

In 2025, bioenergy researchers from Oak Ridge National Laboratory and Idaho National Laboratory held a series of discussions with farmers in Illinois, Tennessee, Alabama, Kansas, and Colorado to get an unfiltered look at the future of biomass resources from the U.S. agricultural sector. Coordinated by Sustainable Oils, Inc., with additional facilitation from the HudsonAlpha Institute for Biotechnology, the meetings were supported by the U.S. Department of Energy’s Bioenergy Technologies Office (DOE BETO).

Parish, Esther [Oak Ridge National Laboratory (ORN↗

Electronic Waste (E-Waste) Recycling: Barriers and Opportunities for State, Local, and Tribal Governments

Electronic waste, or e-waste, encompasses end-of-life electrical and electronic equipment, including computers, monitors, televisions, printers, cell phones, household appliances with electronic components, and small consumer devices containing batteries or circuitry. E-waste is one of the fastest-growing components of the U.S. waste stream, with nearly 8 million tons generated in 2022. E-waste presents two related public-interest considerations. First, e-waste contains economically and strategically important materials: base metals (copper, aluminum, iron, steel), precious metals (gold, silver, platinum group metals), and critical materials such as rare earth elements, gallium, and indium that appear on the U.S. Geological Survey's (USGS) 2025 List of Critical Minerals. Second, many electronic devices contain hazardous constituents - including lead, mercury, cadmium, and brominated flame retardants - as well as rechargeable batteries that can pose fire risks during handling. Effective management of these constituents helps protect workers, communities, and the environment. In the United States, it is estimated that less than 20% of e-waste is formally collected and recycled, leaving over 6 million tons landfilled or otherwise unrecovered. This fact sheet provides state and local decision-makers an overview of (1) e-waste composition and recoverable materials, (2) technology pathways used to recover those materials, and (3) examples of operational and partnership structures used to provide e-waste recycling capacity in the United States. It is intended to complement existing collection-program guidance available through U.S. Environmental Protection Agency (EPA) and other sources.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

Numerical Investigation of the Electrical Resistivity Tomography for Detecting the Waste Zone beneath an Engineered Surface

Surface barriers are an integral part of waste site remediation that are needed to minimize further contamination spread, allow time for additional radionuclide decay, and decrease risks to workers and the environment. Depending on the type of waste, the design life of a surface barrier varies from decades to millennia. The performance and impacts of surface barriers must be monitored beyond the life of most monitoring instruments; hence, long-term monitoring technologies are needed that can non-intrusively assess barrier impacts both in the near surface and to large depths. Innovative geophysical methods such as the electrical resistivity tomography (ERT) are capable of non-intrusively detecting the distribution of soil wetness and/or contaminant plumes in the soil. However, the application of geophysical methods in monitoring a surface barrier system has been very limited because a surface barrier is often composed of multiple components made of natural (e.g., soil, rocks, asphalt) and manufactured (e.g., plastic, metal) materials. In this study, the E4D numerical simulator, developed at Pacific Northwest National Laboratory for inverting the ERT survey data, was used to evaluate the configuration of electrodes for optimized ERT monitoring of waste zone below a surface barrier. The results indicate that, for high-quality mapping of the conditions below the surface barrier, the ERT method requires that some of the electrodes be installed either beneath the surface barrier or in boreholes around the barrier. In reality, for a surface barrier that is being constructed, some electrodes may be installed beneath the non-conductive layer of the surface barrier before or during barrier construction. For a surface barrier that has already been constructed, some electrodes can be installed in a few vertical boreholes around the barrier boundary.

Zhang, Zhuanfang↗

Numerical Investigation of the Electrical Resistivity Tomography for Detecting the Waste Zone beneath an Engineered Surface - 19066

Surface barriers are an integral part of waste site remediation that are needed to minimize further contamination spread, allow time for additional radionuclide decay, and decrease risks to workers and the environment. Depending on the type of waste, the design life of a surface barrier varies from decades to millennia. The performance and impacts of surface barriers must be monitored beyond the life of most monitoring instruments; hence, long-term monitoring technologies are needed that can non-intrusively assess barrier impacts both in the near surface and to large depths. Innovative geophysical methods such as the electrical resistivity tomography (ERT) are capable of nonintrusively detecting the distribution of soil wetness and/or contaminant plumes in the soil. However, the application of geophysical methods in monitoring a surface barrier system has been very limited because a surface barrier is often composed of multiple components made of natural (e.g., soil, rocks, asphalt) and manufactured (e.g., plastic, metal) materials. In this study, the E4D numerical simulator, developed at Pacific Northwest National Laboratory for inverting the ERT survey data, was used to evaluate the configuration of electrodes for optimized ERT monitoring of waste zone below a surface barrier. The results indicate that, for high-quality mapping of the conditions below the surface barrier, the ERT method requires that some of the electrodes be installed either beneath the surface barrier or in boreholes around the barrier. In reality, for a surface barrier that is being constructed, some electrodes may be installed beneath the non-conductive layer of the surface barrier before or during barrier construction. For a surface barrier that has already been constructed, some electrodes can be installed in a few vertical boreholes around the barrier boundary. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

Initial Assessment of Cover Degradation Features at the Mexican Hat, Utah, UMTRCA Disposal Site - 19556

The Mexican Hat, Utah, Uranium Mill Tailings Radiation Control Act (UMTRCA) Title I Disposal Site is located on the Navajo Reservation in southeast Utah. The US Nuclear Regulatory Commission licensed the site to the US Department of Energy Office of Legacy Management (LM) for custody and long-term care. LM manages long-term surveillance and maintenance activities at the site with the principal goal of protecting human health and the environment. The disposal cell was designed to encapsulate low-level radioactive mill tailings and other residual radioactive materials (RRM) in a way that minimizes the need for active maintenance and limits radon gas emanation and precipitation infiltration. The disposal cell has a multicomponent cover, consisting of a 60 cm thick (24 inch), low-permeability, bentonite-amended radon barrier, overlain by a 15 cm thick (6 inch) sandy gravel bedding/filter layer and a 30 cm thick (12 inch) riprap erosion-protection layer. Under UMTRCA, designs intended to control and contain RRM shall be effective for up to 1000 years, to the extent reasonably achievable and, in any case, for at least 200 years. In 2016, multiple subtle depressions were identified on the rock cover along the toe and lower portions of the northeast side slope of the disposal cell. Due to concerns regarding potential impacts to disposal cell performance and erosion resistance, evaluations of the depressions and cell cover design and construction were initiated. The evaluations included reviews of the disposal cell as-built drawings and supporting design calculations for the rock cover components. Also, in 2017, a weather monitoring station was installed at the site to collect continuous site-specific meteorological data, and repeatable ground-based light imaging, detection, and ranging (lidar) topographical and aerial photogrammetry surveys were implemented to monitor for potential changes in the surface depression features. The evaluations also included visual inspections of the depressions, and in 2018, small-area manual excavations of the rock cover components (test pits) were performed to observe the conditions of the cover components, scan for radioactivity, and observe evidence of erosion on the surface of the radon barrier material. Voids and incisions were discovered within the radon barrier on the north and northeast side slopes of the disposal cell. Visual observations at test pits indicate that the bedding/filter material is highly segregated and may not be in conformance with the disposal cell engineering and construction design specifications. Post-construction development of a weak to strongly cemented material has also been observed immediately below the base of the bedding layer in test pits with observed radon barrier degradation. A series of radiological surveys have been performed at the site, and radiological readings have not exceeded natural background conditions in the vicinity of the site. Thus, the site remains protective of human health and the environment. Implementation of continuous radiological monitoring at the site will be initiated in fall 2018 through the deployment of radon cups and thermoluminescent dosimeters to obtain data that provides supporting evidence that the disposal cell remains protective of human health and the environment. Evaluations to determine the cause(s) of the depression features and associated radon barrier erosion are ongoing. Possible mechanisms of cover degradation identified thus far include segregated bedding material that would allow for higher precipitation runoff velocities, resulting in erosion of the radon barrier; post-construction cementation of radon barrier or aeolian material that could negatively affect the performance of the radon barrier; cation exchange leading to the development of cementation; and aeolian deposition affecting precipitation runoff. Moreover, geotechnical sampling and testing is planned to verify spatial cover conditions relative to design specifications. The resulting information will be used to identify possible causes for the surface depressions and associated radon barrier degradation, gain insight on potential long-term performance implications along the side slopes of the disposal cell, and identify potential corrective actions. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

An experimental investigation on the CO 2 storage capacity of the composite confining system

Assuring secure containment of stored CO 2 is of paramount importance—for climate change mitigation, for permitting, and for reassuring the public. Regional seals, such as those sealing petroleum accumulations, have proven to be effective for securing CO 2 . However, the goal of permanent sequestration can also be satisfied with “composite confining systems” consisting of multiple, possibly discontinuous flow barriers that, in aggregate, create a system with very high permeability anisotropy and effectively retard the vertical migration of CO 2 . This study focuses on investigating the barrier characteristics necessary for effective containment of CO 2 , using both physical flow experiments and modified invasion percolation simulations. The simulations are calibrated to the physical experiments and are used to further extend the analysis. Results show that for a composite confining system, a) even barriers with low capillary entry pressure contrast to the underlying flow unit can divert rising CO 2 ; b) curved or anticlinal barrier topography can enhance CO 2 trapping; c) fining-upward gradations make little difference to barrier effectiveness or CO 2 retention; d) longer barriers retain more CO 2 regardless of barrier topography. Finally, field-scale simulations have demonstrated the importance of barrier length for increasing CO 2 storage capacity. Furthermore, the results presented can be used to inform the development of new screening criteria for characterization and effectiveness of composite confining systems.

58 GEOSCIENCES↗