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At least 667 records · Page 37

Development of Guidance for the Disposition of Used Oil and Oil Samples at the Columbia Generating Station - 20232

It is a fact that oil can become contaminated during plant operations. When used oil is collected, the water is decanted from the used oil. The separated used oil is typically analyzed for gamma emitting radionuclides and then sent off-site for processing (incineration) or recycling. If there is no detectable radioactivity, then some plants may release the oil for unrestricted use. Many nuclear power plants have no standard process for evaluating Tritium and Carbon-14 in oil; therefore, there may be variability in how plants are determining whether oil contains Tritium and Carbon-14, and at what concentration. Questions may arise whether there is a technically sound basis and evaluation method for used oil and if process knowledge and/or sampling may be appropriate in making that determination. Recently, there has been an increase in regulatory scrutiny regarding these practices to ensure that the utilities are evaluating oil for all plant-produced radionuclides prior to free release. Regulators have indicated that the requirement to conduct adequate surveys should include evaluating oils for Tritium and Carbon-14. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

Improved and versatile viral 2 A platforms for dependable and inducible high‐level expression of dicistronic nuclear genes in C hlamydomonas reinhardtii

Summary A significantly improved viral 2A peptide system for dependable high‐level expression of dicistronic genes in Chlamydomonas reinhardtii has been developed. Data are presented demonstrating that use of an especially proficient ‘extended FMDV 2A’ coding region allows production of two independent protein products from a dicistronic gene with almost complete efficiency. Importantly, results are also presented that demonstrate the utility of this 2A system for efficient high‐level expression of foreign genes in C. reinhardtii , which has not previously been reliably achievable in this algal model system. To expand the versatility of the 2A expression system, a number of commonly used selectable marker proteins were assessed for their compatibility with the extended FMDV 2A peptide. Additional experiments demonstrate the feasibility and utility of 2A‐containing dicistronic systems that rely on a strong conditional promoter for transcriptional control and a low‐expression marker gene for selection. This strategy allows easy and efficient delivery of genes of interest whose expression levels require regulation either to mitigate potential toxicity or allow differential expression under controlled experimental conditions. Finally, as an additional practical demonstration of the utility of the extended FMDV 2A system, confocal fluorescence microscopy is used to demonstrate that native and foreign proteins of interest bearing post‐translational remnants of the extended FMDV 2A peptide localize correctly to various cellular compartments, including a striking demonstration of the almost exclusive localization of the Rubisco small subunit protein to the pyrenoid of the C. reinhardtii chloroplast in cells maintained under ambient CO 2 concentrations.

Plucinak, Thomas M.↗

Advancing Electric System Resilience with Distributed Energy Resources: Key Questions and Resources

This resource has two complementary parts: (1) A list of questions that offers an initial starting point for state public utility commissions (commissions) to frame how they review proposed utility investments and considerations that could offer resilience benefits; (2) A list of relevant resources to improve a regulator's ability to oversee resilience investments and obtain the best possible solutions for customers. The list of resources includes a synopsis of relevant topics covered in each resource. This document is not intended to offer a complete picture of resilience literature, but instead suggests strategies for state regulators to convene conversations and make decisions to achieve better resilience outcomes for customers. It is meant to serve as a starting point for commissions to understand and incorporate resilience into regulatory processes. The list of questions and resources will not be perfectly suited to the particular needs of each commission. As the resilience conversation advances, regulators will need to take advantage of available resources to build their capacity to assess resilience risks, compare investment options, and evaluate performance.

14 SOLAR ENERGY↗

circRNA expression analysis in lung adenocarcinoma: comparison of paired fresh frozen and formalin-fixed paraffin-embedded specimens

Highlights: • First comparison of circRNA expression from paired fresh frozen and FFPE specimens. • Good correlation in circRNAs expression data utilizing fresh frozen or FFPE tissues. • Samples clustered correctly by differentially expressed circRNAs in either group. • Three differentially expressed circRNAs in lung cancers verified by qRT-PCR assay. • circRNA-miRNA-protein coding gene regulation network analyzed by bioinformatics tools. Circular RNA (circRNAs) is a novel class of endogenous non-coding RNAs which is widely involved in carcinogenesis. Archived formalin-fixed paraffin-embedded (FFPE) specimens represent valuable resources for cancer research. Currently there is a lack of systematic analysis on the feasibility of circRNAs expression analysis using FFPE samples. Here, we reported the first comparison study of circRNA expression from paired fresh frozen and FFPE specimens of lung adenocarcinoma. circRNAs expression of paired lung adenocarcinoma and adjacent normal samples, starting from either fresh frozen or FFPE materials, were analyzed via a high-throughput circRNA microarray. Hierarchical clustering was performed on samples. qRT-PCR was used to confirm the differentially expressed circRNAs. The circRNA regulation networks were built by bioinformatics tools for several candidate circRNAs. Our results demonstrated that there was a good correlation in circRNAs expression analysis utilizing fresh frozen or FFPE tissues. Tumors and adjacent normal tissues can be clustered correctly by the differentially expressed circRNAs in fresh frozen or FFPE groups. Furthermore, three differentially expressed circRNAs, hsa{sub c}ircRNA{sub 1}00421, hsa{sub c}ircRNA{sub 1}04329 and hsa{sub c}ircRNA{sub 1}01969 were verified by qRT-PCR assay. Bioinformatics analysis was also applied to predict the circRNA-miRNA-protein coding gene interaction network for each of above circRNAs. To the best of our knowledge, this is the first report demonstrating that the circRNAs microarray analysis, starting from FFPE specimens, is comparable with that based on fresh frozen samples. Therefore FFPE specimen represents a good substitute for fresh frozen tissue, especially when fresh frozen specimen is limited.

60 APPLIED LIFE SCIENCES↗

Kinetic study of treatment of wastewater contains food preservative agent by anaerobic baffled reactor : An overview

The characteristic of wastewater of food industries with preservative substances is high content of organic substances, degradable and high total suspended solid. High organic content in this waste forced the treatment is biologically and pointed out to anaerobic treatment. Anaerobic showed the better performance of degradation than aerobic for high content organic and also for toxic materials. During that day the treatment of food wastewater is aerobically which is high consume of energy required and high volume of sludge produced. The advantage of anaerobic is save high energy, less product of sludge, less requirement of nutrients of microorganism and high efficiency reduction of organic load. The high efficiency of reduction will reduce the load of further treatment, so that, the threshold limit based on the regulation would be easy to achieve. Research of treatment of wastewater of food industries would be utilized by both big scale industries and small industries using addition of preservative substances. The type reactor of anaerobic process is anaerobic baffled reactor that will give better contact between wastewater and microorganism in the sludge. The variables conducted in this research are the baffled configuration, sludge height, preservative agent contents, hydralic retention time and influence of micro nutrients. The respons of this research are the COD effluent, remaining preservative agent, pH, formation of volatile fatty acid and total suspended solid. The result of this research is kinetic model of the anaerobic baffled reactor, reaction kinetic of preservative agent degradation and technology of treatment wastewater contains preservative agent. The benefit of this research is to solve the treatment of wastewater of food industries with preservative substance in order to achieve wastewater limit regulation and also to prevent the environmental deterioration.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Hierarchical Distributed Voltage Regulation in Networked Autonomous Grids: Preprint

We propose a novel algorithm to solve optimal power flow (OPF) that aims at dispatching controllable distributed energy resources (DERs) for voltage regulation at minimum cost. The proposed algorithm features unprecedented scalability to large distribution networks by utilizing an information structure based on networked autonomous grids (AGs). Specifically, each AG is a subtree of a large distribution network that has a tree topology. The topology and line parameters of each AG are known only to a regional coordinator (RC) that is responsible for communicating with and dispatching the DERs within this AG. The reduced network, where each AG is treated as a node, is managed by a central coordinator (CC), which knows the topology and line parameters of the reduced network only and communicates with all the RCs. We jointly explore this information structure and the structure of the linearized distribution power flow (LinDistFlow) model to derive a hierarchical, distributed implementation of the primal-dual gradient algorithm that solves OPF. The proposed implementation significantly reduces the computation burden compared to the centrally coordinated implementation of the primal-dual algorithm. Numerical results on a 4,521-node test feeder show that the proposed hierarchical distributed algorithm can achieve more than 10-fold improvement in the speed of convergence compared to the centrally coordinated primal-dual algorithm.

24 POWER TRANSMISSION AND DISTRIBUTION↗

Dynamic Phaeodactylum tricornutum exometabolites shape surrounding bacterial communities

Summary Roles of different ecological classes of algal exometabolites in regulating microbial community composition are not well understood. Here, we identify exometabolites from the model diatom Phaeodactylum tricornutum and demonstrate their potential to influence bacterial abundances. We profiled exometabolites across a time course of axenic algal growth using liquid chromatography–tandem mass spectrometry. We then investigated growth of 12 bacterial isolates on individual‐identified exometabolites. Lastly, we compared responses of a P. tricornutum ‐adapted enrichment community to additions of two contrasting metabolites: selective growth substrate 4‐hydroxybenzoic acid and putative signaling/facilitator molecule lumichrome. We identified 50 P. tricornutum metabolites and found distinct temporal accumulation patterns. Two exometabolites (of 12 tested) supported growth of distinct subsets of bacterial isolates. While algal exudates and algal presence drove similar changes in community composition compared with controls, exogenous 4‐hydroxybenzoic acid addition promoted increased abundances of taxa that utilized it in isolation, and also revealed the importance of factors relating to algal presence in regulating community composition. This work demonstrates that secretion of selective bacterial growth substrates represents one mechanism by which algal exometabolites can influence bacterial community composition and illustrates how the algal exometabolome has the potential to modulate bacterial communities as a function of algal growth.

4-hydroxybenzoic acid↗

Hierarchical Distributed Voltage Regulation in Networked Autonomous Grids

We propose a novel algorithm to solve optimal power flow (OPF) that aims at dispatching controllable distributed energy resources (DERs) for voltage regulation at minimum cost. The proposed algorithm features unprecedented scalability to large distribution networks by utilizing an information structure based on networked autonomous grids (AGs). Specifically, each AG is a subtree of a large distribution network that has a tree topology. The topology and line parameters of each AG are known only to a regional coordinator (RC) that is responsible for communicating with and dispatching the DERs within this AG. The reduced network, where each AG is treated as a node, is managed by a central coordinator (CC), which knows the topology and line parameters of the reduced network only and communicates with all the RCs. We jointly explore this information structure and the structure of the linearized distribution power flow (LinDistFlow) model to derive a hierarchical, distributed implementation of the primal-dual gradient algorithm that solves the OPF. The proposed implementation significantly reduces the computation burden compared to the centrally coordinated implementation of the primal-dual algorithm. Numerical results on a 4,521-node test feeder show that the proposed hierarchical distributed algorithm can achieve an improvement of more than tenfold in the speed of convergence compared to the centrally coordinated primal-dual algorithm.

24 POWER TRANSMISSION AND DISTRIBUTION↗

Frequency Regulation Services from Connected Residential Devices: Short Paper

In this paper, we demonstrate the potential benefits that residential buildings can provide for frequency regulation services in the electric power grid. In a hardware-in-the- loop (HIL) implementation, simulated homes along with a physical laboratory home are coordinated via a grid aggregator, and it is shown that their aggregate response has the potential to follow the regulation signal on a timescale of seconds. Connected (communication-enabled), devices in the National Renewable Energy Laboratory's (NREL's) Energy Systems Integration Facility (ESIF) received demand response (DR) requests from a grid aggregator, and the devices responded accordingly to meet the signal while satisfying user comfort bounds and physical hardware limitations. Future research will address the issues of cybersecurity threats, participation rates, and reducing equipment wear-and-tear while providing grid services.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

Short Paper: Frequency Regulation Services from Connected Residential Devices: Preprint

In this paper, we demonstrate the potential benefits that residential buildings can provide for frequency regulation services in the electric power grid. In a hardware-in-the- loop (HIL) implementation, simulated homes along with a physical laboratory home are coordinated via a grid aggregator, and it is shown that their aggregate response has the potential to follow the regulation signal on a timescale of seconds. Connected (communication-enabled), devices in the National Renewable Energy Laboratory's (NREL's) Energy Systems Integration Facility (ESIF) received demand response (DR) requests from a grid aggregator, and the devices responded accordingly to meet the signal while satisfying user comfort bounds and physical hardware limitations. Future research will address the issues of cybersecurity threats, participation rates, and reducing equipment wear-and-tear while providing grid services.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

Inertial storage for satellites

A new system is being developed that performs satellite attitude control, attitude reference, and energy storage utilizing inertia wheels. The baseline approach consists of two counter rotating flywheels suspended in specially designed magnetic bearings, spin axis motor/generators, and a control system. The control system regulates the magnetic bearings and spin axis motor/generators and interacts with other satellite subsystems (photovoltaic array, star trackers, Sun sensors, magnetic torquers, etc.) to perform the three functions. Existing satellites utilize separate subsystems to perform attitude control, provide attitude reference, and store energy. These functions are currently performed using reaction or momentum wheels, gyros, batteries, and devices that provide an absolute reference (Sun sensors and star trackers). A Combined Attitude, Reference, and Energy Storage (CARES) system based on high energy density inertial energy storage wheels (flywheels) has potential advantages over existing technologies. Even when used only for energy storage, this system offers the potential for substantial improvements in life, energy efficiency, and weight over existing battery technologies. Utilizing this same device for both attitude control and attitude reference would result in significant additional savings in overall satellite weight and complexity.

Eisenhaure, D.↗

Editorial: Edge computation and digital distribution networks

The development of digital technologies is penetrating all areas of energy revolution. Based on the in-depth integration of advanced digital technologies, distribution networks are gradually transforming into digital distribution networks (DDNs) with tremendous changes from the structure to the operation mode. DDNs is the digitalized appearance of the physical distribution network, in which ubiquitous connections and massive data are the basic characteristics (Huo et al., 2022). It is an important task to utilize the massive data and propose novel operation modes to construct more efficient and intelligent distribution networks (Jian et al., 2022). Among the advanced digital technologies in DDNs, edge computing has received wide attention (Zhao et al., 2022). It has superior performance in local sensing and intelligent computation, which can effectively relieve huge communication pressure. However, the limited computing resources and the complex computing tasks at the edge side significantly challenge the collaboration of distribution network regulation and advanced digital technologies (Hu et al., 2022). It is necessary to find out proper methods to utilize advanced digital technology to construct DDNs. This Research Topic is organized to introduce the recent progress in the construction, operation and advanced computational methods for DDNs. Finally, seven papers have been accepted, which can be sorted into the following three categories: 1) Evolution and technical features of DDNs, 2) Intelligent operation control of DDNs, 3) Advanced simulation for large-scale DDNs. The three sections below respectively introduce the major research and contributions of the papers covered in each category.

24 POWER TRANSMISSION AND DISTRIBUTION↗

Adaptive Control of a Utility-Scale Wind Turbine Operating in Region 3

Adaptive control techniques are well suited to nonlinear applications, such as wind turbines, which are difficult to accurately model and which have effects from poorly known operating environments. The turbulent and unpredictable conditions in which wind turbines operate create many challenges for their operation. In this paper, we design an adaptive collective pitch controller for a high-fidelity simulation of a utility scale, variable-speed horizontal axis wind turbine. The objective of the adaptive pitch controller in Region 3 is to regulate generator speed and reject step disturbances. The control objective is accomplished by collectively pitching the turbine blades. We use an extension of the Direct Model Reference Adaptive Control (DMRAC) approach to track a reference point and to reject persistent disturbances. The turbine simulation models the Controls Advanced Research Turbine (CART) of the National Renewable Energy Laboratory in Golden, Colorado. The CART is a utility-scale wind turbine which has a well-developed and extensively verified simulator. The adaptive collective pitch controller for Region 3 was compared in simulations with a bas celliansesical Proportional Integrator (PI) collective pitch controller. In the simulations, the adaptive pitch controller showed improved speed regulation in Region 3 when compared with the baseline PI pitch controller and it demonstrated robustness to modeling errors.

Frost, Susan A.↗

Wheeling and Banking Strategies for Optimal Renewable Energy Deployment. International Experiences

This paper defines the principles of wheeling (i.e., transmission) tariffs and renewable energy (RE) banking provisions and their role in RE deployment in countries with plans for large-scale RE. It reviews experiences to date in the United States, Mexico, and India and discusses key policy and regulatory considerations for devising more effective wheeling and/or banking provisions for countries with ambitious RE deployment targets. The paper addresses the challenges of competing needs of stakeholders, especially those of RE generators, distribution utilities, and transmission network owners and operators. The importance of wheeling and banking and their effectiveness for financial viability of RE deployment is also explored. This paper aims to benefit policymakers and regulators as well as key renewable energy stakeholders. Key lessons for regulators include: creating long-term wheeling and banking policy certainty, considering incentivizing RE through discounted transmission access, and assessing the cost implications of such discounts, as well as expanding access to renewable energy customers.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

Snail transcription factor NLS and importin β1 regulate the subcellular localization of Cathepsin L and Cux1

Several recent studies have highlighted an additional unexpected localization and site of action for Cathepsin L (Cat L) protease within the nucleus in breast, colon and prostate cancer, however, its role in the nucleus was unclear. It was proposed to mediate proteolytic processing of the transcription factor CCAAT-displacement protein/cut homeobox transcription factor (Cux1) from the full-length p200 isoform to generate the p110 and p90 isoforms, of which the p110 isoform was shown to act as a cell cycle regulator to accelerate entry into the S phase. The p110 isoform has also been shown to bind to the promoter regions of Snail and E-cadherin to activate Snail and inactivate E-cadherin transcription, thus promoting epithelial mesenchymal transition (EMT). Mechanistic studies on what drives Cat L nuclear localization have not been reported. Our hypothesis is that Snail shuttles into the nucleus with Cat L through binding to importin-β. Snail knockdown with siRNA in MDA-MB-468 breast cancer cells led to nuclear to cytoplasmic shuttling of Cat L and decreased levels of Cux1, while overexpression of Snail in MCF-7 breast cancer cells or HEK-293 human embryonic kidney cells led to increased nuclear expression of both Cat L and Cux1. Additionally, transient transfection of Snail NLS mutants not only abrogated Snail nuclear localization but also nuclear localization of Cat L and Cux1. Interestingly, importin β1 knockdown with siRNA decreased Snail and Cux1 levels, as well as nuclear localization of Cat L. Therefore, we show for the first time that the nuclear localization of Cat L and its substrate Cux1can be positively regulated by Snail NLS and importin β1, suggesting that Snail, Cat L and Cux1 all utilize importin β1 for nuclear import. - Highlights: • Snail expression is associated with increased nuclear expression of Cathepsin L (Cat L) and Cux1. • Snail NLS is required for nuclear localization of Cat L and Cux1. • Importin β1 is required for Snail, Cat L and Cux1 expression/nuclear localization.

60 APPLIED LIFE SCIENCES↗

Identification of a DYRK1A-mediated phosphorylation site within the nuclear localization sequence of the hedgehog transcription factor GLI1

GLI1 is a key downstream transcription effector of the Hedgehog (Hh) signaling pathway that is involved in promoting cell growth, differentiation and tissue patterning in embryonic development. GLI1 over-activation and its nuclear localization has also been linked to the increased aggressiveness of a number of cancers. It has previously been demonstrated that DYRK1A (dual-specificity tyrosine-regulated kinase 1A) can phosphorylate GLI1 and promote GLI1 nuclear localization and its transcriptional activity. Utilizing recombinant human GLI1 and DYRK1A proteins and phospho-peptide mass spectrometry, we demonstrated that GLI1 is phosphorylated by DYRK1A at Ser408, a phospho-site that falls within the putative nuclear localization sequence (NLS) of GLI1, suggesting a possible mechanistic role in modulating its translocation. Further, we showed that the Ser408 site on GLI1 was not phosphorylated in the presence of the selective DYRK1A inhibitor harmine. The data described herein provide the first identification of a DYRK1A-mediated site of phosphorylation on GLI1 within its NLS and may serve as a valuable mechanism for further understanding Hh signaling modulation. - Highlights: • We describe a novel direct DYRK1A phosphorylation site on GLI1 at Ser408. • Harmine a selective DYRK1A inhibitor, blocks DYRK1A-mediated GLI1 phosphorylation. • The Ser408 phospho-site is within the GLI1 nuclear localization sequence (380–420). • This phosphorylation site provides a potential anti-Hh therapeutic target.

60 APPLIED LIFE SCIENCES↗

Making coal relevant for small scale applications: Modular gasification for syngas/engine CHP applications in challenging environments

Small-scale coal gasification technology, coupled to a reciprocating engine generator, has the potential for making coal a cost competitive resource for meeting the flexible energy needs and resiliency requirements of utilities across the United States. To maintain grid stability and reliability, electrical generation must be regulated to match the load at the proper voltage and frequency. With the expansion of intermittent sources into the grid, such as wind and solar, frequency and voltage regulation become increasingly important and challenging. This work presents the results of a Front End Engineering Design (FEED) effort to detail the engineering and preliminary economics of a small-scale, air blown, fixed-bed gasification process, operating at near-atmospheric pressure, with gas cleanup to provide syngas and pyrolysis liquid fuels for use in reciprocating engine generators for combined heat and power at the University of Alaska Fairbanks. A very detailed assessment of capital and operating costs allows the evaluation of a levelized cost of electricity of 208.06 $/MWh, which can be reduced through the selling of by-products (steam for heating purposes and pyrolysis liquids to be used for power generation in an existing diesel engine). Here, a combined sensitivity analysis, based on the Monte Carlo approach, has been carried out to evaluate the effects of the uncertainties (capital and operating costs and plant annual availability) on the LCOE.

01 COAL, LIGNITE, AND PEAT↗

Planning green infrastructure placement based on projected precipitation data

Continued urbanization has led to tremendous changes on the landscape. These changes have exacerbated the effects of extreme climatic events such as flooding because of constrained water infiltration and increased surface flow. Typical runoff control measures involve sophisticated gray infrastructure that guide excess surface flow into storage and disposal sites. In a dynamic climate system, these measures are not sustainable since they cannot be easily modified to accommodate large volumes of runoff. Green Infrastructure (GI) is an adaptable technique that can be used to minimize runoff, in addition to offering an array of additional benefits (urban heat regulation, aesthetics, improved air quality etc.). Strategic placement of GI is key to achieving maximum utility. While physical site characteristics play a major role in determining suitable GI placement sites, knowledge of future precipitation patterns is crucial to ensure successful flood mitigation. Here, suitable GI sites within the city of Knoxville, Tennessee, were determined based on potential impact of an extreme flood event as indicated by site characteristics. Then, the relative potential likelihood of a flood event was determined based on projected precipitation data and knowledge of existing flood zones. By combining potential impact with likelihood information, low, medium, and high priority GI implementation sites were established. Results indicate that high priority sites are in the central parts of the city with priority decreasing outward. The GI prioritization scheme presented here, offers valuable guidance to city planners and policy makers who wish to exploit the GI approach for flood mitigation.

54 ENVIRONMENTAL SCIENCES↗