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At least 487 records · Page 27

Early Diagnosis of Fibromyalgia Using Surface-Enhanced Raman Spectroscopy Combined with Chemometrics

Fibromyalgia (FM) is a chronic muscle pain disorder that shares several clinical features with other related rheumatologic disorders. This study investigates the feasibility of using surface-enhanced Raman spectroscopy (SERS) with gold nanoparticles (AuNPs) as a fingerprinting approach to diagnose FM and other rheumatic diseases such as rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), osteoarthritis (OA), and chronic low back pain (CLBP). Blood samples were obtained on protein saver cards from FM (n = 83), non-FM (n = 54), and healthy (NC, n = 9) subjects. A semi-permeable membrane filtration method was used to obtain low-molecular-weight fraction (LMF) serum of the blood samples. SERS measurement conditions were standardized to enhance the LMF signal. An OPLS-DA algorithm created using the spectral region 750 to 1720 cm -1 enabled the classification of the spectra into their corresponding FM and non-FM classes (Rcv > 0.99) with 100% accuracy, sensitivity, and specificity. The OPLS-DA regression plot indicated that spectral regions associated with amino acids were responsible for discrimination patterns and can be potentially used as spectral biomarkers to differentiate FM and other rheumatic diseases. This exploratory work suggests that the AuNP SERS method in combination with OPLS-DA analysis has great potential for the label-free diagnosis of FM.

60 APPLIED LIFE SCIENCES↗

Quality Investigation of Pultruded Carbon Fiber Panels Subjected to Four-Point Flexure via Fiber Optic Sensing

Pultruded carbon fiber-reinforced composites are attractive to the wind energy industry due to the rapid production of highly aligned unidirectional composites with enhanced fiber volume fractions and increased specific strength and stiffness. However, high volume carbon fiber manufacturing remains cost-prohibitive. This study investigates the feasibility of a pultruded low-cost textile carbon fiber-reinforced epoxy composite as a promising material in spar cap production was undertaken based on mechanical response to four-point flexure loading. As spar caps are primarily subjected to flexural loading, large-span four-point flexure was considered, and coupon testing was restricted to tensile modulus and compression strength assessment. High-resolution spatial fiber optic strain sensing was utilized to determine spatial strain distribution during four-point flexure, revealing consistent strain along the length of the part and proved to be an excellent option for process manufacturing quality examination. Additionally, holes with diameters of 2.49 mm, 5.08 mm, and 1.93 mm were drilled through the thickness of full-width parts to determine the feasibility of structural health monitoring of pultruding parts internal to wind blades via fiber optic strain sensing.

Chemistry↗

EMS-Induced Mutagenesis of Clostridium carboxidivorans for Increased Atmospheric CO 2 Reduction Efficiency and Solvent Production

Clostridium carboxidivorans (P7) is one of the most important solvent-producing bacteria capable of fermenting syngas (CO, CO 2 , and H 2 ) to produce chemical commodities when grown as an autotroph. This study aimed to develop ethyl methanesulfonate (EMS)-induced P7 mutants that were capable of growing in the presence of CO 2 as a unique source of carbon with increased solvent formation and atmospheric CO 2 reduction to limit global warming. Phenotypic analysis including growth and end product characterization of the P7 wild type (WT) demonstrated that this strain grew better at 25 °C than 37 °C when CO 2 served as the only source of carbon. In the current study, 55 mutagenized P7-EMS mutants were developed by using 100 mM and 120 mM EMS. Interestingly, using a forward genetic approach, three out of the 55 P7-EMS mutants showed a significant increase in ethanol, butyrate, and butanol production. The three P7-EMS mutants presented on average a 4.68-fold increase in concentrations of ethanol when compared to the P7-WT. Butyric acid production from 3 P7-EMS mutants contained an average of a 3.85 fold increase over the levels observed in the P7-WT cultures under the same conditions (CO 2 only). In addition, one P7-EMS mutant presented butanol production (0.23 ± 0.02 g/L), which was absent from the P7-WT under CO 2 conditions. Most of the P7-EMS mutants showed stability of the obtained end product traits after three transfers. Most importantly, the amount of reduced atmospheric CO 2 increased up to 8.72 times (0.21 g/Abs) for ethanol production and up to 8.73 times higher (0.16 g/Abs) for butyrate than the levels contained in the P7-WT. Additionally, to produce butanol, the P7-EMSIII-J mutant presented 0.082 g/Abs of CO 2 reduction. This study demonstrated the feasibility and effectiveness of employing EMS mutagenesis in generating solvent-producing anaerobic bacteria mutants with improved and novel product formation and increased atmospheric CO 2 reduction efficiency.

59 BASIC BIOLOGICAL SCIENCES↗

Machine Learning Downscaling of SoilMERGE in the United States Southern Great Plains

SoilMERGE (SMERGE) is a root-zone soil moisture (RZSM) product that covers the entire continental United States and spans 1978 to 2019. Machine learning techniques, Random Forest (RF), eXtreme Gradient Boosting (XGBoost), and Gradient Boost (GBoost) downscaled SMERGE to spatial resolutions straddling the field scale domain (100 to 3000 m). Study area was northern Oklahoma and southern Kansas. The coarse resolution of SMERGE (0.125 degree) limits this product’s utility. To validate downscaled results in situ data from four sources were used that included: United States Department of Energy Atmospheric Radiation Measurement (ARM) observatory, United States Climate Reference Network (USCRN), Soil Climate Analysis Network (SCAN), and Soil moisture Sensing Controller and oPtimal Estimator (SoilSCAPE). In addition, RZSM retrievals from NASA’s Airborne Microwave Observatory of Subcanopy and Surface (AirMOSS) campaign provided a nearly spatially continuous comparison. Three periods were examined: era 1 (2016 to 2019), era 2 (2012 to 2015), and era 3 (2003 to 2007). During eras 1 and 2, RF outperformed XGBoost and GBoost, whereas during era 3 no model dominated. Performance was better during eras 1 and 2 as opposed to the pre-L band era 3. Improvements across all eras, regions, and models realized from downscaling included an increase in correlation from 0.03 to 0.42 and a decrease in ub RMSE from -0.0005 to -0.0118 m 3 /m 3 . This study demonstrates the feasibility of SMERGE downscaling opening the prospect for the development of a long-term RZSM dataset at a more desirable field-scale resolution with the potential to support diverse hydrometeorological and agricultural applications.

54 ENVIRONMENTAL SCIENCES↗

Searching for Dwarf H$α$ Emission-line Galaxies within Voids. I. Survey Methods and First Observations

The population density of dwarf galaxies in low-density voids is likely determined by the dark matter halo mass function and how galaxy formation proceeds in smaller halos. This depends on the nature of dark matter itself, making the dwarf galaxy population a tracer of its properties. While dwarfs have been found in smaller, closer voids, they have proven difficult to find in larger, more distant voids through magnitude-limited spectroscopic surveys. This is because these surveys detect an overwhelmingly large number of objects behind the voids that must be verified spectroscopically, making void surveys prohibitively inefficient and expensive in terms of large-telescope time. Narrowband imaging for emission lines such as Hα reduces the number of background objects, although the overall number remains large. If imaging is done through a filter set with overlapping transmission wings, then object redshift can be estimated from photometry alone. The precision possible is an order of magnitude greater than single-band photometry, with the caveat that the captured line must be identified through other means. Broadband photometry can be used to reject enough objects with emission of an unwanted type to make obtaining spectra of the remaining objects feasible. In this study, we present an Hα survey for dwarf galaxies with M r ' fainter than -14 mag through the center 4.3 square degrees of the void FN8. Using Sloan $g^{\prime} ,r^{\prime} ,i^{\prime}$ photometry, we exclude enough [O II ] and [O III ] emitters that follow-up spectra of only a few dozen objects are required to statistically estimate the void population density.

79 ASTRONOMY AND ASTROPHYSICS↗

Effect of sintering temperature on adhesion of spray-on piezoelectric transducers

Conventionally sol-gel spray-on transducers require a high-temperature (> 700 ◦C) sintering process; however, this process can affect the microstructure of the substrate material. For mechanical elbows and valves utilized for fluid transport in the energy sector, the components are designed to have a specific microstructure, and deviations from these specifications can create weak points in the system. For this reason it is important to investigate how the temperature of the deposition process affects the substrate. This paper investigates the effect of high-temperature and low-temperature (< 150 ◦C) processing conditions on the surface composition of the substrate. Furthermore, the resultant transducers from high- and low-temperature fabrication processes are compared to determine if a low-temperature processing method is feasible. For these studies a sol-gel spray-on process is employed to deposit piezoelectric ceramics onto a stainless-steel 316L substrate. Energy-dispersive X-ray spectroscopy is utilized to determine the composition of the substrate surface before and after transducer deposition. Results indicate that the high-temperature processing conditions may alter the surface composition of the metal due to a diffusion of the metal into the ceramic, which results in a metal surface that is bonded to the ceramic. Furthermore, it is shown that low-temperature processing of spray-on transducers is a viable method for transducer fabrication where the resultant transducers meet the industry minimum requirement of 30 dB signalto-noise ratio. In parallel simulation calculations, finite-element method (FEM) studies were performed to model the adhesive strength of the low-temperature processed transducer to the substrate surface. Comparisons between the simulations and experiments suggest that the bond strength is much greater than the commercial gel bonds and closer to hardened epoxy glue bonds. These results indicate that spray-on transducers fabricated under lowtemperature processing conditions are a viable solution for leave-in-place monitoring of structures.

M. Sinding, Kyle↗

Progressive collapse analysis of stiffened panel structure with consideration of actual welding distortion and residual stresses

To date, inclusion of welding distortion and residual stresses in determining the strength of marine structures is based on empirical formulations due to welding complexity. In this study, a more feasible numerical model was developed from the perspective of inherent strain theory. The accuracy of this simplified numerical model was confirmed by transient thermo-elastic–plastic finite element analysis using a novel dynamic mesh refining and iterative substructure method which is 50 times faster than conventional finite element method. Welding distortion by the two numerical approaches was validated with experimental measurement. The collapse analyses indicated that the inherent strain model predicted a compressive strength and load-displacement curve with high accuracy, as validated by the transient thermo-mechanical model. The global stiffness and the ultimate strength of the welded structure would be overestimated by about 22% if no welding effects were considered. The proposed computation procedure for determining the ultimate strength of welded structures is accurate, simple, and practical and enables improvement of ultimate strength through optimization of welding joint design to reduce the welding residual stress and distortion.

Huang, Hui↗

Recovery of Cs-137 from Electric Arc Furnace Dust - 20562

The present work proposes the Cs-137 recovery from Electric Arc Furnace Dusts (EAFD) by leaching, in order to reduce the volume of radioactive waste to be managed. Leaching tests were performed on different samples of EAFD contaminated with Cs-137. Two leaching methodologies were tested: dynamic and static using as medium distilled water and in some cases NaOH. The results indicate the possibility of recovering Cs-137 from EAFD using the dynamic method; however, the recovery efficiencies of Cs-137 depend on EAFD's chemical composition. The leachates of Cs-137 were quantitatively adsorbed on exchange resins, showing its great potential to isolate or contain the Cs-137 recovery from EAFD. This study shows the feasible to apply the dynamic leaching methodology to recover Cs-137 from EAFD and the use of ion exchange resins for the isolation of removed Cs-137. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

Modeling of H2 Dispersion at ARIES

Hydrogen is a versatile and clean energy carrier that can be produced from various renewable sources such as wind, solar, and hydropower and help decarbonize electricity grids, industry, and transportation. Using the Hydrogen Research Facility under Advanced Research on Integrated Energy Systems (ARIES) at the National Renewable Energy Laboratory's (NREL) Flatirons campus as a test bench, the study examines the feasibility, useability, and value of using computational fluid dynamics (CFD) techniques to model hydrogen dispersion. The ARIES facility was chosen because controlled hydrogen releases can be performed at a rate of 27 kg-H2/hr. Site-specific atmospheric and weather condition data such as wind speed and temperature were used as inputs to the model. The results show statistical distributions and ranges of hydrogen concentrations at locations throughout the domain. Wind conditions are found to significantly impact the release behavior, including the hydrogen cloud's direction and concentrations. At low wind speeds (below 1 mph), hydrogen forms a cloud and at higher wind speeds (> 2-4 mph) hydrogen plume stretches in the direction of wind momentum. From >100 simulations for ARIES site-specific conditions, statistical quantities combined with a clustering algorithm were used to propose sensor location at various elevations from ground.

dispersion↗

Effective Defect Detection Using Instance Segmentation for NDI

Ultrasonic testing is a common Non-Destructive Inspection (NDI) method used in aerospace manufacturing. However, the complexity and size of the ultrasonic scans make it challenging to identify defects through visual inspection or machine learning models. Using computer vision techniques to identify defects from ultrasonic scans is an evolving research area. In this study, we used instance segmentation to identify the presence of defects in the ultrasonic scan images of composite panels that are representative of real components manufactured in aerospace. We used two models based on Mask- RCNN (Detectron 2) and YOLO 11 respectively. Additionally, we implemented a simple statistical pre-processing technique that reduces the burden of requiring custom-tailored pre-processing techniques. Our study demonstrates the feasibility and effectiveness of using instance segmentation in the NDI pipeline by significantly reducing data pre-processing time, inspection time, and overall costs.

computer vision techniques↗

Single-Walled Carbon Nanotubes with Confined Chalcogens as the Catalysts and Electrodes for Oxygen Reduction Reaction in Fuel Cells

The goal of this project is to synthesize and characterize a new non-metal electro-catalyst for oxygen reduction reaction (ORR) for fuel cell applications. The intended catalyst is a composite material composed of sulfur chains encapsulated in narrow diameter single-walled carbon nanotubes (S@SWNTs). S@SWNTs were successfully synthesized through sulfur vapor infusion method, and validated with Raman spectroscopy. However, the electrochemical analysis on the ORR catalytic activity of S@SWNTs indicated that it had low ORR catalytic activity. Our theoretical study based on density functional theory (DFT) revealed that the poor oxygen adsorption (low binding energy) on the surface of S@SWNTs was the bottleneck of the entire catalytic reaction. The focus of the project was subsequently pivoted to the development of a new non-noble metal ORR catalyst that could provide durability in acidic electrolyte. The hypothesis was to encapsulate small iron (Fe) clusters in SWNTs (Fe@SWNTs) can provide ORR electro-catalytic activity and long durability in acidic environment. DFT-based computational studies were carried out to explore the feasibility of the Fe@SWNTs catalyst. The theoretical study indicated that Fe@SWNTs indeed could catalyze the ORR with lower theoretical overpotential than platinum (Pt). However, its weaker bonding energy with oxygen was the bottleneck of the overall reaction. On the other hand, Fe clusters (composed of 7 Fe atoms) encapsulated in nitrogen-doped SWNTs (Fe 7 @N 4 WSNTs) showed proper oxygen adsorption by the Fe cluster and low theoretical overpotential of ORR. Comparing to the Fe single atom catalyst on N-doped SWNTs (Fe-N 4 SWNTs), which is one the best non-noble metal ORR catalysts reported in the literature, the Fe 7 @N 4 WSNTs showed lower overpotential and better resistance to acidic environment. Fe encapsulated N-doped SWNTs were synthesized with ferrocene as the Fe precursors through vapor infusion method, and experimental validate is underway. This study theoretically demonstrated the feasibility of a new type of non-noble metal electro-catalyst for ORR that could have high catalytic activity and long durability.

08 HYDROGEN↗

Considerations for a Medium-Voltage DC Electrolysis Testbed

Here we present the results of a study focused on the feasibility of using Medium Voltage DC (MVDC) power distribution from wind power generation to electrolyzers for hydrogen production. This approach, using hybrid energy generation in a MVDC microgrid, offers many advantages. These include possible improvements in efficiency, reliability and installation cost compared to a more typical state-of-the-art AC distribution configuration. It also eliminates the need for transformers, which have recently been subject to price volatility and availability concerns. This study highlights the practical feasibility of MVDC distribution networks for integrating various energy sources, offering improved efficiency and reduced system complexity compared to conventional AC-based solutions. Future work will focus on enhancing fault protection strategies, scaling the system to larger renewable installations, and conducting hardware implementation at the National Renewable Energy Laboratory's (NREL) Flatirons Campus (FC). In the sections that follow we show that a DC Collection and Distribution System (DC CDS) reduces the losses associated with the electrical conversion / distribution process relative to a state-of-the-art AC approach, improving overall efficiency by 5%. On the qualitative side, reducing the number of conversion stages is likely to improve reliability, reduce capital investment cost, and enable simpler control algorithms to be used, and reduced risk of instabilities and malfunctions.

08 HYDROGEN↗

Domesticating a food spoilage yeast into an organic acid–tolerant metabolic engineering host: Lactic acid production by engineered Zygosaccharomyces bailii

Lactic acid represents an important class of commodity chemicals, which can be produced by microbial cell factories. However, due to the toxicity of lactic acid at lower pH, microbial production requires the usage of neutralizing agents to maintain neutral pH. Zygosaccharomyces bailii, a food spoilage yeast, can grow under the presence of organic acids used as food preservatives. This unique trait of the yeast might be useful for producing lactic acid. With the goal of domesticating the organic acid!tolerant yeast as a metabolic engineering host, seven Z. bailii strains were screened in a minimal medium with 10 g/L of acetic, or 60 g/L of lactic acid at pH 3. The Z. bailii NRRL Y7239 strain was selected as the most robust strain to be en- gineered for lactic acid production. By applying a PAN!ARS!based CRISPR!Cas9 system consisting of a transfer RNA promoter and NAT selection, we demonstrated the targeted deletion of ADE2 and site!specific integration of Rhizopus oryzae ldhA coding for lactate dehydrogenase into the PDC1 locus. The resulting pdc1::ldhA strain produced 35 g/L of lactic acid without ethanol production. Here, this study de- monstrates the feasibility of the CRISPR!Cas9 system in Z. bailii, which can be applied for a fundamental study of the species.

59 BASIC BIOLOGICAL SCIENCES↗

Solving the duck curve in a smart grid environment using a non-cooperative game theory and dynamic pricing profiles

With the intermittency that comes with electricity generation from renewables, utilizing dynamic pricing will encourage the demand-side to respond in a smart way that would minimize the electricity costs and flatten the net electricity demand curve. Determining the optimal dynamic pricing profile that would leverage distributed storage to flatten the curve is a novel idea that needs to be studied. Moreover, the economic feasibility of utilizing distributed electrical energy storage is still not given in the literature. Therefore, in this paper, a novel way of solving a citywide dynamic model using a bilevel programming algorithm is introduced. The problem is developed as a novel non-cooperative Stackelberg game that utilizes air-conditioning systems and electrical storage through the end-users to determine the optimal dynamic pricing profile. The results show that the combined effect of utilizing demand-side air-conditioning systems and distributed storage together can flatten the curve while employing the optimal dynamic pricing profile. An economic study is performed to determine the economic feasibility of 20 different cases with different battery designs and the level of solar penetration. Three metrics were used to evaluate the economic performance of each case: the levelized cost of storage, the levelized cost of energy, and the simple payback period. Most cases had levelized cost of storage values lower than 0.457 $/kWh, which is the lower bound available in the literature. Seven out of 16 cases have a simple payback period shorter than the lifetime of the system (25 years). The case with a 100 MW PV power plant and a battery storage of size 597 MWh, was found to be the most promising case with a simple payback period of 12.71 years for the photovoltaic plant and 19.86 years for the demand-side investments.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

Preoperative Radiosurgery for Resected Brain Metastases: The PROPS-BM Multicenter Cohort Study

Preoperative radiosurgery (SRS) is a feasible alternative to postoperative SRS, with potential benefits in adverse radiation effect (ARE) and leptomeningeal disease (LMD) relapse. However, previous studies are limited by small patient numbers and single-institution designs. Our aim was to evaluate preoperative SRS outcomes and prognostic factors from a large multicenter cohort (Preoperative Radiosurgery for Brain Metastases [PROPS-BM]).

62 RADIOLOGY AND NUCLEAR MEDICINE↗

High harmonic generation in mixed XUV and NIR fields at a free-electron laser

Abstract We present the results of an experiment investigating the generation of high-order harmonics by a femtosecond near-infrared (NIR) laser pulse in the presence of an extreme ultraviolet (XUV) field provided by a free-electron laser (FEL), a process referred to as XUV-assisted high-order harmonic generation (HHG). Our experimental findings show that the XUV field can lead to a small enhancement in the harmonic yield when the XUV and NIR pulses overlap in time, while a strong decrease of the HHG yield and a red shift of the HHG spectrum is observed when the XUV precedes the NIR pulse. The latter observations are in qualitative agreement with model calculations that consider the effect of a decreased number of neutral emitters but are at odds with the predicted effect of the correspondingly increased ionization fraction on the phase matching. Our study demonstrates the technical feasibility of XUV-assisted HHG experiments at FELs, which may provide new avenues to investigate correlation-driven electron dynamics as well as novel ways to study and control propagation effects and phase matching in HHG.

47 OTHER INSTRUMENTATION↗

Uinta Basin CarbonSAFE II: Storage Complex Feasibility (Final Report)

The primary objective of this CarbonSAFE Phase II project was to establish the technical and commercial feasibility of a commercial-scale CO 2 geological storage complex for Deseret Power Electric Cooperative Bonanza Power Plant and other CO 2 sources in the northeast Uinta Basin, Utah, with the goal to securely store at least 50 million metric tons of captured CO 2 and accelerate CO 2 capture, utilization, and storage (CCUS) deployment. The project team established high-potential technical and commercial feasibility for a storage site within the east Uinta Basin (Utah), in the Cretaceous sandstones (Frontier, Dakota, and Buckhorn), Entrada Sandstone, Nugget Sandstone, and/or Weber Sandstone southwest of the Bonanza coal-fired power plant. This project collected and analyzed state-of-the-art data to characterize the storage complex consistent with Environmental Protection Agency (EPA) permitting standards. The team conducted extensive analog studies, outcrop mapping, and data sampling, which largely contributed to understanding the subsurface lithology and facies. Existing data were obtained and assessed from Utah Division of Oil, Gas, and Mining (DOGM), Utah Geological Survey (UGS), Colorado Geological Survey (CGS), U.S. Geological Survey (USGS), and EPA. These data were analyzed using state-of-the-art CCUS technologies for Societal Considerations, Site Characterization, Modeling and Simulations, Risk Assessment, Management and Monitoring, potential Underground Injection Control (UIC) Class VI Well Permitting, and Technical/Economic Feasibility. Through these high-resolution data collection and feasibility studies, this project was expected to provide a reference for initiating Underground Injection Control (UIC) and other commercial-scale geological storage permitting processes in the Western United States, ultimately contributing to the nation's decarbonization goals through low-risk, cost-effective commercial-scale carbon capture, utilization, and storage (CCUS) projects.

42 ENGINEERING↗

Technical and economic feasibility of molten chloride salt thermal energy storage systems

A techno-economic study is performed to assess the feasibility of molten chloride salt thermal energy storage (TES) systems for next generation concentrating solar power. Refractory liners internally insulate tanks to allow tank shells to be constructed from carbon steel. The liner must not be wetted by salt to maintain predictable thermal properties and manageable heat loss out of the tank. The commercial scale tank liner is an anchored brick and mortar design with expansion joints to accommodate thermal expansion. Furthermore, finite element analysis is performed to optimize the thermal and mechanical profile of the tank. Equalizing the shell temperature between the water-cooled foundation and the shell wall is necessary to minimize differential thermomechanical stress and lower overall stress values below industrial allowable limits. The cost of the TES system is estimated to be $60/kWhth, which is four times greater than Department of Energy targets. Solutions to reduce system cost and overall risk are proposed.

14 SOLAR ENERGY↗