Association of Classroom Ventilation with Reduced Illness Absence: A Prospective Study in California Elementary Schools
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32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
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Correlation of free-response and receiver-operating-characteristic area-under-the-curve estimates: Results from independently conducted FROC/ROC studies in mammography
Purpose: From independently conducted free-response receiver operating characteristic (FROC) and receiver operating characteristic (ROC) experiments, to study fixed-reader associations between three estimators: the area under the alternative FROC (AFROC) curve computed from FROC data, the area under the ROC curve computed from FROC highest rating data, and the area under the ROC curve computed from confidence-of-disease ratings. Methods: Two hundred mammograms, 100 of which were abnormal, were processed by two image-processing algorithms and interpreted by four radiologists under the FROC paradigm. From the FROC data, inferred-ROC data were derived, using the highest rating assumption. Eighteen months afterwards, the images were interpreted by the same radiologists under the conventional ROC paradigm; conventional-ROC data (in contrast to inferred-ROC data) were obtained. FROC and ROC (inferred, conventional) data were analyzed using the nonparametric area-under-the-curve (AUC), (AFROC and ROC curve, respectively). Pearson correlation was used to quantify the degree of association between the modality-specific AUC indices and standard errors were computed using the bootstrap-after-bootstrap method. The magnitude of the correlations was assessed by comparison with computed Obuchowski-Rockette fixed reader correlations. Results: Average Pearson correlations (with 95% confidence intervals in square brackets) were: Corr(FROC, inferred ROC) = 0.76[0.64, 0.84] > Corr(inferred ROC, conventional ROC) = 0.40[0.18, 0.58] > Corr (FROC, conventional ROC) = 0.32[0.16, 0.46]. Conclusions: Correlation between FROC and inferred-ROC data AUC estimates was high. Correlation between inferred- and conventional-ROC AUC was similar to the correlation between two modalities for a single reader using one estimation method, suggesting that the highest rating assumption might be questionable.
60 APPLIED LIFE SCIENCES↗
In vitro selection and analysis of SARS-CoV-2 nirmatrelvir resistance mutations contributing to clinical virus resistance surveillance
To facilitate the detection and management of potential clinical antiviral resistance, in vitro selection of drug-resistant severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) against the virus M pro inhibitor nirmatrelvir (Paxlovid active component) was conducted. Six M pro mutation patterns containing T304I alone or in combination with T21I, L50F, T135I, S144A, or A173V emerged, with A173V+T304I and T21I+S144A+T304I mutations showing >20-fold resistance each. Biochemical analyses indicated inhibition constant shifts aligned to antiviral results, with S144A and A173V each markedly reducing nirmatrelvir inhibition and M pro activity. SARS-CoV-2 surveillance revealed that in vitro resistance–associated mutations from our studies and those reported in the literature were rarely detected in the Global Initiative on Sharing All Influenza Data database. In the Paxlovid Evaluation of Protease Inhibition for COVID-19 in High-Risk Patients trial, E166V was the only emergent resistance mutation, observed in three Paxlovid-treated patients, none of whom experienced COVID-19–related hospitalization or death.
60 APPLIED LIFE SCIENCES↗
Quantitative cardiac phosphoproteomics profiling during ischemia-reperfusion in an immature swine model
Ischemia-reperfusion (I/R) results in altered metabolic and molecular responses, and phosphorylation is one of the most noted regulatory mechanisms mediating signaling mechanisms during physiological stresses. To expand our knowledge of the potential phosphoproteomic changes in the myocardium during I/R, we used Isobaric Tags for Relative and Absolute Quantitation-based analyses in left ventricular samples obtained from porcine hearts under control or I/R conditions. The data are available via ProteomeXchange with identifier PXD006066. We identified 1,896 phosphopeptides within left ventricular control and I/R porcine samples. Significant differential phosphorylation between control and I/R groups was discovered in 111 phosphopeptides from 86 proteins. Analysis of the phosphopeptides using Motif-x identified five motifs: (..R..S..), (..SP..), (..S.S..), (..S…S..), and (..S.T..). Semiquantitative immunoblots confirmed site location and directional changes in phosphorylation for phospholamban and pyruvate dehydrogenase E1, two proteins known to be altered by I/R and identified by this study. Novel phosphorylation sites associated with I/R were also identified. Functional characterization of the phosphopeptides identified by our methodology could expand our understanding of the signaling mechanisms involved during I/R damage in the heart as well as identify new areas to target therapeutic strategies.
60 APPLIED LIFE SCIENCES↗
Screening of Viral Pathogens from Pediatric Ileal Tissue Samples after Vaccination
In 2010, researchers reported that the two US-licensed rotavirus vaccines contained DNA or DNA fragments from porcine circovirus (PCV). Although PCV, a common virus among pigs, is not thought to cause illness in humans, these findings raised several safety concerns. In this study, we sought to determine whether viruses, including PCV, could be detected in ileal tissue samples of children vaccinated with one of the two rotavirus vaccines. A broad spectrum, novel DNA detection technology, the Lawrence Livermore Microbial Detection Array (LLMDA), was utilized, and confirmation of viral pathogens using the polymerase chain reaction (PCR) was conducted. The LLMDA technology was recently used to identify PCV from one rotavirus vaccine. Ileal tissue samples were analyzed from 21 subjects, aged 15–62 months. PCV was not detected in any ileal tissue samples by the LLMDA or PCR. LLMDA identified a human rotavirus A from one of the vaccinated subjects, which is likely due to a recent infection from a wild type rotavirus. LLMDA also identified human parechovirus, a common gastroenteritis viral infection, from two subjects. Additionally, LLMDA detected common gastrointestinal bacterial organisms from the Enterobacteriaceae , Bacteroidaceae , and Streptococcaceae families from several subjects. This study provides a survey of viral and bacterial pathogens from pediatric ileal samples, and may shed light on future studies to identify pathogen associations with pediatric vaccinations.
59 BASIC BIOLOGICAL SCIENCES↗
Probabilistic Assessment of Damage from Same Shock Response Spectra due to Variations in Damping
Interpretation of field data from shock tests and subsequent assessment of product safety margins via laboratory testing are based on the shock response spectra (SRS). The SRS capture how a single degree of freedom (SDOF) structure responds to the shock at differing frequencies and, therefore, no longer contain the duration or other temporal parameters pertaining to the shock. A single duration can often be included in the technical specification or in the recreation of acceleration vs. time history from the specified SRS; however, there is little basis for that beyond technical judgment. The loss of such temporal information can result in the recreated SRS being the same while its effect on a system or component can be different. This paper attempts to quantify this deficiency as well as propose a simple method of capturing damping from shock waves that can allow the original waveform to be more accurately reconstructed from the SRS. In this study the decay rate associated with various frequencies that comprise the overall shock was varied. This variation in the decay rate leads to a variation in the acceleration vs. time history, which can be correlated to a “Damage Index” that captures the fatigue damage imparted to the object under shock. Several waveforms that have the same SRS but varying rates of decay for either high- or low-frequency components of the shock were investigated. The resulting variation in stress cycles and Damage Index is discussed in the context of the lognormal distribution of fatigue failure data. It is proposed that, along with the SRS, the decay rate is also captured to minimize the discrepancy between field data and representative laboratory tests.
36 MATERIALS SCIENCE↗
Transcriptome-Wide Cleavage Site Mapping on Cellular mRNAs Reveals Features Underlying Sequence-Specific Cleavage by the Viral Ribonuclease SOX
Many viruses express factors that reduce host gene expression through widespread degradation of cellular mRNA. An example of this class of proteins is the mRNA-targeting endoribonuclease SOX from the gamma-herpesvirus Kaposi’s sarcoma-associated herpesvirus (KSHV). Previous studies indicated that cleavage of messenger RNAs (mRNA) by SOX occurs at specific locations defined by the sequence of the target RNA, which is at odds with the down-regulation of a large portion of cellular transcripts. In this study, we address this paradox by using high-throughput sequencing of cleavage intermediates combined with a custom bioinformatics-based analysis pipeline to identify SOX cleavage sites across the mRNA transcriptome. These data, coupled with targeted mutagenesis, reveal that while cleavage sites are specific and reproducible, they are defined by a degenerate sequence motif containing a small number of conserved residues rather than a strong consensus sequence. This degenerate element is well represented in both human and KSHV mRNA, and its presence correlates with RNA destabilization by SOX. This represents a new endonuclease targeting strategy, in which use of a degenerate targeting element enables RNA cleavage at specific locations without restricting the range of targets. Furthermore, it shows that strong target selectivity can be achieved without a high degree of sequence specificity.
59 BASIC BIOLOGICAL SCIENCES↗
International land Model Benchmarking (ILAMB) Package v001.00
As a contribution to International Land Model Benchmarking (ILAMB) Project, we are providing new analysis approaches, benchmarking tools, and science leadership. The goal of ILAMB is to assess and improve the performance of land models through international cooperation and to inform the design of new measurement campaigns and field studies to reduce uncertainties associated with key biogeochemical processes and feedbacks. ILAMB is expected to be a primary analysis tool for CMIP6 and future model-data intercomparison experiments. This team has developed initial prototype benchmarking systems for ILAMB, which will be improved and extended to include ocean model metrics and diagnostics.
54 ENVIRONMENTAL SCIENCES↗
International land Model Benchmarking (ILAMB) Package v002.00
As a contribution to International Land Model Benchmarking (ILAMB) Project, we are providing new analysis approaches, benchmarking tools, and science leadership. The goal of ILAMB is to assess and improve the performance of land models through international cooperation and to inform the design of new measurement campaigns and field studies to reduce uncertainties associated with key biogeochemical processes and feedbacks. ILAMB is expected to be a primary analysis tool for CMIP6 and future model-data intercomparison experiments. This team has developed initial prototype benchmarking systems for ILAMB, which will be improved and extended to include ocean model metrics and diagnostics.
54 ENVIRONMENTAL SCIENCES↗
Heterogeneous recycling in fast reactors
Current sodium fast reactor (SFR) designs have avoided the use of depleted uranium blankets over concerns of creating weapons grade plutonium. While reducing proliferation risks, this restrains the reactor design space considerably. This project will analyze various blanket and transmutation target configurations that could broaden the design space while still addressing the non-proliferation issues. The blanket designs will be assessed based on the transmutation efficiency of key minor actinide (MA) isotopes and also on mitigation of associated proliferation risks. This study will also evaluate SFR core performance under different scenarios in which depleted uranium blankets are modified to include minor actinides with or without moderators (e.g. BeO, MgO, B 4 C, and hydrides). This will be done in an effort to increase the sustainability of the reactor and increase its power density while still offering a proliferation resistant design with the capability of burning MA waste produced from light water reactors (LWRs). Researchers will also analyze the use of recycled (as opposed to depleted) uranium in the blankets. The various designs will compare MA transmutation efficiency, plutonium breeding characteristics, proliferation risk, shutdown margins and reactivity coefficients with a current reference sodium fast reactor design employing homogeneous recycling. The team will also evaluate the out-of-core accumulation and/or burn-down rates of MAs and plutonium isotopes on a cycle-by-cycle basis. This cycle-by-cycle information will be produced in a format readily usable by the fuel cycle systems analysis code, VISION, for assessment of the sustainability of the deployment scenarios.
22 GENERAL STUDIES OF NUCLEAR REACTORS↗
Voltage Impacts of Utility-Scale Distributed Wind
Although most utility-scale wind turbines in the United States are added at the transmission level in large wind power plants, distributed wind power offers an alternative that could increase the overall wind power penetration without the need for additional transmission. This report examines the distribution feeder-level voltage issues that can arise when adding utility-scale wind turbines to the distribution system. Four of the Pacific Northwest National Laboratory taxonomy feeders were examined in detail to study the voltage issues associated with adding wind turbines at different distances from the sub-station. General rules relating feeder resistance up to the point of turbine interconnection to the expected maximum voltage change levels were developed. Additional analysis examined line and transformer overvoltage conditions.
17 WIND ENERGY↗
Using the H Index to Assess Impact of DOE National Laboratories
The most readily accessible elements of the Emerald Matrix by quantitative measures are the knowledge and economy related measures. In this paper, the H Index for an institution will be used to assess STE impact, which is in the knowledge generation element. The H Index was developed by Hirsch (2005) as a measure of an individual’s scientific impact. The H Index is defined as the number of publications that have been cited h or more times for a given author. It has been generalized to organizations. Doing so leads to a complication in that H index scales with the number of publications. Although this may not be problematic when comparing individual researchers, it systematically favors larger institutions. Molinari and Molinari (2008) proposed an alternative index (hm) designed to assess organizational impact. It transforms the H Index for an organization into an impact index by removing a factor dependent on the number of publications. The hm provides another approach to compare institutions provided that differences in the citation patterns associated with fields of study are addressed. Kinney (2007) used the Molinari and Molinari (2008) approach to compare various scientific institutions in nonbiomedical research areas. Kinney (2007) used the Thomson Reuters Web of Science (WoS) as the source and used publications in nonbiomedical research areas, which is very important because the research areas of universities are much broader than say a DOE national laboratory. Also there are differences in citation rates for the various research fields that make comparisons between individuals or organizations difficult. The results from Kinney (2007) are given in Table 1 and indicate that the DOE national laboratories compare favorably with the selected universities in terms of impact (hm) in the research areas used in Kinney’s analysis. This report will compare hm for DOE national laboratories using an approach similar to Kinney (2007) providing a measure of impact of the DOE national laboratories.
97 MATHEMATICS AND COMPUTING↗
Models and methods for assessing the value of HVDC adn MVDC technologies in modern power grids (Annual Report, Executive Summary)
Evolution of today’s predominantly alternating current (ac) transmission grid in to mixed ac transmission – high-voltage direct current (HVdc) systems is expected with the decreasing costs of and advancements in power electronics technologies. The recent technological advancements include the development of more efficient and compact voltage source converters (VSCs) that can provide fast response. Because of their controllability and fast response, HVdc systems provide the ability to enhance reliability of the ac transmission grid through frequency support, voltage control, and congestion relief. The HVdc systems can also provide other ancillary services to enhance the economics and reliability of the ac transmission grids, and to optimize their performance. The tools, models, and methods developed to evaluate their benefits will be key enablers to understanding the value proposition introduced by the fast-acting HVdc systems. The main motivation of this work was to develop models and methods to explore and quantify the technical and economic benefits of HVdc systems and fast response VSC technologies in the future grid of United States. The models and methods explore the benefits of HVdc systems through provision of controlled active/reactive power and fast response. The fast response can provide much-needed multiobjective services to the grid (e.g., frequency response, voltage control) while moving blocks of energy. The models and methods can be applied to study other power electronics technologies and scenarios such as those undertaken in ongoing studies led by the North American Electric Reliability Corporation (NERC) Inverter-based Resource Performance Task Force (IRPTF). The IRPTF studies identify the problems associated with power electronics-based technologies as they are integrated in to the bulk power system (or the ac transmission system).
24 POWER TRANSMISSION AND DISTRIBUTION↗
Testing a novel peptide drug towards a goal of reducing mortality in critically ill COVID19 patients
COVID 19 has been devastating the globe over the past year, and although our knowledge of how the disease progresses is constantly evolving, there is a significant amount we now about the mechanisms underlying COVID19. There is growing evidence that a 'cytokine storm' is a significant driver of mortality associated with COVID19, with studies showing high levels of hallmark inflammatory indicators in critically ill COVID19 patients. This essentially consists of the patient's immune system going awry and causing white blood cells to constantly release a large number of small molecules called cytokines. The result of this is further activation of the immune system, which ends up attacking not only infected but also healthy patient tissues, resulting in organ failure.
59 BASIC BIOLOGICAL SCIENCES↗
Extending the Air and Moisture Leakage Calculator to add Residential Buildings and Additional Commercial Buildings
The DOE Windows and Building Envelope Research and Development Roadmap for Emerging Technologies shows that in 2010, infiltration was responsible for 4 quads of space conditioning primary energy use in the residential and commercial sectors. The relative contribution of air leakage in building heating and cooling load is increasing with improvement in the thermal resistance of building envelopes. Advanced air barrier technologies and construction practices have been developed to reduce air leakage in buildings. However, limited information on the impact of air barrier technologies on energy consumption and the durability of buildings has hindered their adoption. In the past Oak Ridge National Laboratory (ORNL), the National Institute of Standards and Technology (NIST), Air Barrier Association of America (ABBA), and U.S.-China Clean Energy Research Center for Building Energy Efficiency (CERC-BEE) collaborated to develop an online calculator that estimates the potential energy and cost savings in major U.S., Canadian and Chinese cities from improvement in air tightness in commercial buildings. In 2018–2019, the calculator was expanded to add moisture transfer calculations given that air leakage through the building envelope can have a significant impact on moisture transfer and associated impacts. In this study, the calculator is expanded further by adding data for two additional commercial buildings (strip mall and primary school) and a residential building. The team investigated the impact of airtightness on energy consumption and moisture transfer of the added buildings. The study includes the analysis of air tightness in 52 major cities in the U.S. and 5 cities in Canada.
32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
Implementation of Detailed Polyethylene Pyrolysis Kinetics into CFD Simulations using Machine Learning
Municipal solid waste (MSW) and waste plastics have received significant attention due to the issues of waste generation and storage, as well as their potential as an energy resource. High-density polyethylene (HDPE) makes up a large portion of plastic waste and has been the subject of several conversion studies. However, the mechanisms associated with converting HDPE through pyrolysis and gasification are extensive and complex making them difficult to implement into high-fidelity computational fluid dynamic (CFD) simulations. For this project, a primary pyrolysis mechanism containing 42 unique species and 737 heterogeneous reactions was used to generate kinetic data over a range of operating conditions. A machine learning (ML) model was developed to replicate the results of the detailed pyrolysis mechanism while significantly increasing the computational efficiency. A deep operator network (DeepONet) architecture was adopted to train the model using time steps relevant to CFD simulations. The ML used physics-based loss functions to ensure mass conservation. The ML model has been deployed in simple MFiX CFD simulations, single particle, and an experimental drop tube reactor, and has shown promising performance compared to the original scheme.
Houston, Ross↗
Reference Station Risk Assessment for Refueling Heavy-Duty Vehicles Using HyRAM+
The deployment of heavy-duty (HD) hydrogen fuel cell vehicles that are entering the market now is driving the need for expanded HD hydrogen refueling station infrastructure to meet demand. This expansion must prioritize safety and reliability, necessitating careful consideration of the associated risks. In this study, we use a light-duty (LD) hydrogen refueling station as a comparative tool to quantify the risks for a HD station, which is essentially a scaled-up version of a LD station.
08 HYDROGEN↗