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This document summarizes peer review comments and scores for the fiscal year 2023 U.S. Department of Energy (DOE) Hydrogen Program Annual Merit Review and Peer Evaluation Meeting (AMR), held June 6-9, 2023. This review process provides project- and program-level evaluations of DOE-funded research, development, demonstration, and analysis of hydrogen and fuel cell technologies.
The Energy Policy Act of 1992 (EPAct) was enacted in part to reduce the nation's dependence on imported petroleum. Provisions of EPAct require certain fleets to acquire alternative fuel vehicles (AFVs). The U.S. Department of Energy administers these requirements through its State and Alternative Fuel Provider Fleet Program, Federal Fleet Requirements, and Alternative Fuel Designation Authority. This report summarizes activities under the program during model year 2023.
The Accident Tolerant Fuels (ATF) program aims to develop next generation Light Water Reactor (LWR) fuels with improved performance, reliability, and safety. The program has developed a roadmap to support the insertion of lead fuel rods (LFRs) or lead fuel assemblies (LFAs) of an accident tolerant fuel into a commercial LWR by the end of FY 2022. In order to achieve this goal, novel fuel compositions and cladding materials are being assembled as drop-in irradiation experiments to allow for prioritization of concepts to further the ATF mission. Development of fabrication methodology and qualification techniques for small-scale irradiation test samples is reported.
The American Association of Physicists in Medicine began the Medical Physics Leadership Academy Journal Club in the fall of 2020. The initiative was launched to provide a forum for medical physicists to learn about leadership topics using published material, discuss and reflect on the material, and consider incorporating the discussed skills into their professional practice. This report presents the framework for the MPLA Journal Club program, describes the lessons learned over the last 2 years, summarizes the data collected from attendees, and highlights the roadmap for the program moving forward.
Nanoconfinements are utilized to program how polymers entangle and disentangle as chain clusters to engineer pseudo bonds with tunable strength, multivalency, and directionality. When amorphous polymers are grafted to nanoparticles that are one magnitude larger in size than individual polymers, programming grafted chain conformations can "synthesize" high-performance nanocomposites with moduli of ≈25GPa and a circular lifecycle without forming and/or breaking chemical bonds. These nanocomposites dissipate external stresses by disentangling and stretching grafted polymers up to ≈98% of their contour length, analogous to that of folded proteins; use both polymers and nanoparticles for load bearing; and exhibit a non-linear dependence on composition throughout the microscopic, nanoscopic, and single-particle levels.
The Green Ocean Amazon (GoAmazon2014/5) scientific program focused on the influence of aerosols and surface fluxes on tropical cloud formation. This major research effort gathered high-quality environmental data over the central Amazon basin during 2014 and 2015. The present work is a contribution to the GoAmazon2014/5 investigations with an emphasis on the behaviour of the most important mechanism of precipitation over the tropics: mesoscale convective systems (MCSs). To provide a background, MCSs' tracks obtained from infrared satellite images over the entire Amazon basin in 2014–2015 are compared with climatological values. We report the number of MCSs and precipitation in the basin is about 50% lower than compared to the climatology for 2000–2013. We argue that the below average occurrence of MCSs during the GoAmazon2014/5 program can be explained, at least in part, by the effects of positive anomalies in sea surface temperature over the equatorial Pacific Ocean, negative moisture transport toward the Amazon basin, and by the anticyclonic phase of the mode of interannual and intraseasonal variability over South America. Special attention is given to the 99 MCSs that occurred over the GoAmazon2014/5 site. The impact of MCSs on the meteorological variables over the GoAmazon2014/5 sites is examined, and the contribution of MCSs to rainfall over that region is estimated to be about 70% of the total. Finally, the synoptic and thermodynamic conditions related to the MCSs' genesis and dissipation are discussed. It is suggested that in days with reduced MCS genesis over the GoAmazon2014/5 region, the ventilation over the continent by easterly winds from the relative cold South Atlantic Ocean favours convection at locations near the ocean as compared to those inland.
Abstract Large regional programs to restore riverine habitat for fish and aquatic organisms have become common throughout North America, Europe, and elsewhere. Evaluating the effectiveness of projects implemented under these programs—sometimes called programmatic monitoring and evaluation—has proven challenging, and little guidance exists on programmatic monitoring and evaluation approaches and their effectiveness. In this paper, we review different approaches for evaluating the effectiveness of river restoration projects implemented across a region. These programmatic monitoring and evaluation approaches include case studies, meta-analyses, multiple before–after control–impact (mBACI), extensive posttreatment (EPT), intensively monitored watersheds (IMWs), and hybrid programmatic approaches that use a combination of different experimental designs. For each approach, we discuss the pros and cons as well as provide examples. The most appropriate approach depends in part on the questions that the programmatic monitoring and evaluation strives to address, the spatial and temporal scale at which detection of a response is expected, and the scale of inference. Case studies and mBACI approaches can answer questions about individual projects but have several limitations in terms of cost, timely results, and feasibility. A meta-analysis, which can provide broadly applicable results, is dependent upon a large number of case studies being completed. The EPT approach can provide relatively quick and easy-to-interpret results, but it requires a large population of completed projects and careful selection of controls. The IMW approach has been broadly applied in western North America but has had limited success and appears to be tractable only in small catchments where restoration and monitoring can be well controlled. Based on results from recent efforts in the USA and Europe, the most feasible programmatic monitoring and evaluation approach in terms of cost, implementability, and production of timely results appears to be a hybrid approach that uses a combination of the EPT and mBACI approaches.
Abstract The historical distribution of Sockeye Salmon Oncorhynchus nerka in the Columbia River basin has been constrained by the species’ dependence on nursery lakes for juvenile rearing. Several productive lake systems were impounded by dams during the last century leading to the extirpation of Sockeye Salmon from many nursery lakes in the region. Recent efforts to re‐establish populations in historically natal areas are exemplified by the Cle Elum Lake reintroduction program. The program is founded on outplanting adult fish from two middle Columbia River donor populations with different adaptive potentials. We used genetic stock identification methods to differentiate stock origins between Osoyoos Lake ( OSO ) and Lake Wenatchee ( WEN ) donor stocks and to evaluate the relative productivity from two brood years (2011 and 2012) of natural spawning in the novel environment. Spawning ground surveys revealed assortative mating between earlier‐spawning WEN fish that were more abundant farthest upstream and later‐spawning OSO fish that were concentrated (82%) downstream nearest the lake. Hybrids accounted for only 5% of sampled smolts and 4% of adult returns. Smolts rearing in Cle Elum Lake were significantly larger overall ( OSO , 140 mm; WEN , 129 mm) than smolts in either donor population (84 mm). However, the average size of OSO smolts varied among emigration years, and relative smolt abundances favored the WEN stock (70% overall), indicative of a rearing survival advantage. In relation, the WEN stock exhibited a better average rate of replacement (0.80) in adult‐to‐adult escapement compared with the OSO stock (0.17). Continued monitoring will focus on trends in productivity and potential demographic shifts that may arise in the Cle Elum Lake population and will provide managers with information concerning limiting factors in the environment that might affect similar approaches to reintroductions in other lake systems.
An open-source program named VeloxChem has been developed for the calculation of electronic real and complex linear response functions at the levels of Hartree–Fock and Kohn–Sham density functional theories. With an object-oriented program structure written in a Python/C++ layered fashion, VeloxChem enables time-efficient prototyping of novel scientific approaches without sacrificing computational efficiency, so that molecular systems involving up to and beyond 500 second-row atoms (or some 10,000 contracted and in part diffuse Gaussian basis functions) can be routinely addressed. In addition, VeloxChem is equipped with a polarizable embedding scheme for the treatment of the classical electrostatic interactions with an environment that in turn is modeled by atomic site charges and polarizabilities. The underlying hybrid message passing interface (MPI)/open multiprocessing (OpenMP) parallelization scheme makes VeloxChem suitable for execution in high-performance computing cluster environments, showing even slightly beyond linear scaling for the Fock matrix construction with use of up to 16,384 central processing unit (CPU) cores. An efficient—with respect to convergence rate and overall computational cost—multifrequency/gradient complex linear response equation solver enables calculations not only of conventional spectra, such as visible/ultraviolet/X-ray electronic absorption and circular dichroism spectra, but also time-resolved linear response signals as due to ultra-short weak laser pulses.
Programming for today’s quantum computers is making significant strides toward modern workflows compatible with high performance computing (HPC), but fundamental challenges still remain in the integration of these vastly different technologies. Quantum computing (QC) programming languages share some common ground, as well as their emerging runtimes and algorithmic modalities. In this short paper, we explore avenues of refinement for the quantum processing unit (QPU) in the context of many-tasks management, asynchronous or otherwise, in order to understand the value it can play in linking QC with HPC. Through examples, we illustrate how its potential for scientific discovery might be realized.
RadICalc is a cross-platform program designed to calculate the intensity of radiation released by the decay of arbitrary isotopic mixtures. It was developed to address the need for a program that could calculate the composition, activity, and measurable radiation of a sample over time without significant effort from end-users. RadICalc uses Bateman's solutions for radioactive decay to determine activity over time. Radiation intensities are subsequently calculated using a database containing information about alpha particles, beta electrons, gamma- rays, conversion and Auger electrons, and X-rays. The user interface accepts input for isotopic mixture, initial number of atoms, and time passed since sample composition was known. Results are plotted graphically, and there is a search interface provided to and isotopes of interest. RadICalc can determine activity and radiation expected at specific masses with user-defined molecules in addition to atomic species; the latter is useful in mass based isotope separations for radiometric counting applications, a novel method under development at PNNL.
In non-small cell lung cancer (NSCLC) patients, the expression of tumor programmed death ligand 1 (PD-L1) is an important parameter for deciding the timing of the use of anti-programmed cell death 1 (PD-1) antibody. There has been increasing concern over the benefit of anti-PD-1 antibody in high-risk patients, such as those with preexisting interstitial lung disease (ILD). However, the status and value of PD-L1 as a predictive biomarker and the efficacy of anti-PD-1 antibody in NSCLC patients with preexisting ILD remains uncertain. We retrospectively reviewed the medical records of advanced/recurrent NSCLC patients who had undergone analysis of the tumor PD-L1 expression. We identified 358 patients with advanced/recurrent NSCLC who had undergone analysis of tumor PD-LI expression. Of these, 210 received anti-PD-1 antibody. Tumor-cell PD-L1 expression was similar between the groups with and without preexisting ILD (median, 35%; interquartile range, 0–70%; vs. median, 10%; interquartile range, 1–68%; p = 0.66). Of the 210 patients who received anti-PD-1 antibody, 14 patients had preexisting ILD. The progression-free survival (PFS) showed no significant difference between the patients receiving anti-PD-1 antibody with and without preexisting ILD (median PFS, 4.3 vs. 5.3 months; HR, 0.97; p = 0.84). Within the patients with preexisting ILD, the PFS was tended to be longer in the patients with tumor PD-L1 expression ≥ 50% than in those with tumor PD-L1 expression < 50% (median PFS, 12.5 vs. 2.5 months; HR, 0.47; p = 0.14). The value of PD-L1 expression as a biomarker may be comparable between patients with and without preexisting ILD.
We introduce a methodology for optimally locating fixed disinfectant booster stations for response to contamination incidents in water distribution networks. In this work a stochastic programming problem considering uncertainty in both the location and time of the contamination incident is formulated, resulting in a large Mixed Integer Linear Programming problem. While the original full-space problem is intractably large, we show a series of reductions that decrease the size of the problem by up to five orders of magnitude and allow solutions of the optimal placement problem for realistically-sized water network models.
The Rod-Extremity and Gadolinia AnaLysis (REGAL) Program is a joint international effort to expand the nuclide inventory experimental data for irradiated nuclear fuel, with a specific focus on addressing two challenging needs associated with the characterization of modern, high duty, nuclear fuel. The first challenge is filling the gaps in experimental nuclide inventory data for gadolinia (UO 2 –Gd 2 O 3 ) fuel rods. The huge absorption cross sections of Gd-155 and Gd-157 in the Gd dopant in these rods lead to atypical spatial self-shielding patterns and have an impact on the neutronic environment within the fuel assembly compared to regular UO 2 fuel rods. Additionally, the second challenge is investigating the impact of burnup gradients at rod extremities on fuel composition and neutron leakage, to provide relevant experimental data for assessing computational capabilities to model such impact. A benchmark has been defined as a first step in the development of best-estimate models in the preliminary phase of the experimental data evaluation. Comparison of experimental results obtained in Phase I of the program for two measured pressurized water reactor (PWR) samples, one UO 2 and one UO 2 –Gd 2 O 3 sample, with calculated results obtained with different computational tools based on the defined benchmark are presented and discussed.
Recent advances in the Langlands program shed light on a vast area of modern mathematics from an unconventional viewpoint, including number theory, gauge theory, representation, knot theory and etc. By applying to physics, these novel perspectives endow with a unified account of the (integer/ fractional) quantum Hall effect. The plateaus of the Hall conductance are described by Hecke eigensheaves of the geometric Langlands correspondence. Especially, the particle-vortex duality, which is explained by S-duality of Chern–Simons theory, corresponds to the Langlands duality in Wilson and Hecke operators. Moreover the Langlands duality in the quantum group associated with the Hamiltonian describes fractal energy spectrum structure, know as Hofstadter’s butterfly. These results suggest that the Langlands program has many physically realistic meanings.
Prior research has shown load reduction estimates from residential event-driven demand response programs (e.g., Critical Peak Pricing)using X of the highest Y days with a weather adjustment method are the best performing within the class of currently used baseline methods. However, they are still biased relative to estimates produced from randomized control trials (RCTs), the unbiased “gold standard” evaluation method. In this paper we identify underlying factors that cause some of the bias found in one commonly used baseline method. Rather than simply quantifying bias, our research provides a deeper understanding of what causes the bias and thus can be used to develop more accurate methods that are not subject to these underlying factors. Previous studies have compared various baseline methods relative to each other; however, because all baseline methods are biased, it is impossible to determine the true bias that exists in them. We have access to a unique RCT dataset: the Sacramento Municipal Utility District's study of critical peak pricing. Our analysis of 23 event days over two summers allows us to identify the true bias on load reduction estimates by using the RCT estimates as the unbiased gold standard against which we compare the estimates from the baseline methods. We found that spillover of energy reductions, from hours targeted by a program onto other hours, is one underlying factor that is a major cause of bias in baseline methods. We discuss alternative baseline methods that may not be subject to this same bias.
Mycobacterium tuberculosis (MTB) displays the remarkable ability to transition in and out of dormancy, a hallmark of the pathogen’s capacity to evade the immune system and exploit susceptible individuals. Uncovering the gene regulatory programs that underlie the phenotypic shifts in MTB during disease latency and reactivation has posed a challenge. We develop an experimental system to precisely control dissolved oxygen levels in MTB cultures in order to capture the transcriptional events that unfold as MTB transitions into and out of hypoxia-induced dormancy. Using a comprehensive genome-wide transcription factor binding map and insights from network topology analysis, we identify regulatory circuits that deterministically drive sequential transitions across six transcriptionally and functionally distinct states encompassing more than three-fifths of the MTB genome. The architecture of the genetic programs explains the transcriptional dynamics underlying synchronous entry of cells into a dormant state that is primed to infect the host upon encountering favorable conditions.
The C Programming Language is known for being an efficient language that can be compiled on almost any architecture and operating system. However the absence of dynamic safety checks and a relatively weak type system allows programmer oversights that are hard to spot. In this paper, we present RTC, a runtime monitoring tool that instruments unsafe code and monitors the program execution. RTC is built on top of the ROSE compiler infrastructure. RTC finds memory bugs and arithmetic overflows and underflows, and run-time type violations. Most of the instrumentations are directly added to the source file and only require a minimal runtime system. As a result, the instrumented code remains portable. In tests against known error detection benchmarks, RTC found 98% of all memory related bugs and had zero false positives. Finally, in performance tests conducted with well known algorithms, such as binary search and MD5, we determined that our tool has an average run-time overhead rate of 9.7× and memory overhead rate of 3.5×.