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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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All sourcesNASA NTRSDOE OSTI
DOE OSTI2024

Innovating the next generation of commercial smart building software

Nearly 30% of commercial building energy use is wasted due to equipment faults and HVAC controls problems. The result is increased emissions, compromised comfort and productivity, and less reliable coordination of building power needs with a clean grid. The energy impact alone represents $17 billion in potential savings. Today’s smart building software provides a robust solution to address these operational deficiencies. Energy management and information systems (EMIS) are saving up to 9% on average, with two-year paybacks. They are being incorporated into energy management processes, commissioning services, and utility programs. As effective as they are, two barriers prevent even deeper benefits; limited personnel to fix problems once they are identified, and the expense and time to manually implement changes in control systems. In partnership with the research community, the EMIS industry is developing new capabilities to overcome these barriers. Moving beyond siloed products for either fault detection and diagnostics, or optimal control, these new capabilities empower users to not only automatically identify faults, but also to push corrective action, and control improvements to their buildings. In this paper, several areas for enhancements are documented: ‘one-time’ correction of faults such as setpoints, schedules, and economizer lockouts; short-term active testing for automated proportional integral derivative (PID) loop tuning and functional testing; and continuous supervisory control for demand flexibility and year-round efficiency. Results are presented from a pair of partner implementations out of a dozen providers integrating these enhancements into their products, including field tests from across the country, and insights into operator acceptance and integration into operations and maintenance practices.

Casillas, Armando↗
DOE OSTI2025

Size‐Controlled Cobalt Nanoplates and Their Impact on Oxygen Evolution Catalysis

Controlling the size of nanoparticles is important in catalytic reactions, not only for tuning the surface area but also for modifying the electronic structure. However, achieving precise size control in 2D structures remains challenging. In this work, we demonstrate precise size control of cobalt nanoplates, ranging from 19 nm to 80 nm, which is achieved by tuning the ratio of two surfactants used in the synthesis. The 19 nm of Co nanoplates exhibit higher oxygen evolution reaction activity due to a higher proportion of {10$\overline{1}$1} to {0001} facets. In conclusion, this size control allows systematic investigation into how nanoplate dimensions influence catalytic performance in the oxygen evolution reaction, offering new insights into structure-activity relationships of cobalt nanocatalysts.

defect↗
DOE OSTI2025

Thick graded interfaces increase wear resistance in Ti/TiN nanolayered thin films

Multilayered composites with nanoscale layer thickness incorporating titanium and titanium nitride (Ti/TiN) are used as a model system to study the effects of heterophase interface structure on elastic and plastic deformation, as well as wear behavior. Here, in this work, hardness, modulus, and wear rate under dry reciprocating sliding contact are quantified as a function of Ti-TiN heterophase interfacial nitrogen gradient thickness for Ti/TiN multilayers with 10–80 nm layer thickness. Hardness and modulus are found to be inversely proportional to layer thickness and independent of interface gradient for most specimens. Wear rate is found to be inversely proportional to interface gradient thickness at constant layer thickness, demonstrating that control of nanoscale interface structure is a valid approach to enhancing wear behavior. The materials studied in this work wear comparably or slower than other Ti- and TiN-based composites in the literature, providing a promising avenue for engineering wear-resistant materials for use in industrially relevant applications.

Graded interfaces↗
DOE OSTI2026

Resource-Adaptive Federated Text Generation with Differential Privacy

In cross-silo federated learning (FL), sensitive text datasets remain confined to local organizations due to privacy regulations, making repeated training for each downstream task both communication-intensive and privacy-demanding. A promising alternative is to generate differentially private (DP) synthetic datasets that approximate the global distribution and can be reused across tasks. However, pretrained large language models (LLMs) often fail under domain shift, and federated finetuning is hindered by computational heterogeneity: only resource-rich clients can update the model, while weaker clients are excluded, amplifying data skew and the adverse effects of DP noise. We propose a flexible participation framework that adapts to client capacities. Strong clients perform DP federated finetuning, while weak clients contribute through a lightweight DP voting mechanism that refines synthetic text. To ensure the synthetic data mirrors the global dataset, we apply control codes (e.g., labels, topics, metadata) that represent each client’s data proportions and constrain voting to semantically coherent subsets. This two-phase approach requires only a single round of communication for weak clients and integrates contributions from all participants. Experiments show that our framework improves distribution alignment and downstream robustness under DP and heterogeneity.

Wang, Jiayi [ORNL]↗
DOE OSTI2024

Interactions between phosphate and arsenic in iron/biochar-treated groundwater: Corrosion control insights from column experiments

An increasing number of studies have reported the coexistence of arsenic (As) and phosphorus at high concentrations in groundwater, which threatens human health and increases the complexity of groundwater remediation. However, limited work has been done regarding As interception in the presence of phosphate in flowing systems. In this study, a series of experiments were conducted to evaluate the interactions between phosphate and As during As removal by iron (Fe)-based biochar (FeBC). The addition of phosphate promoted As removal by FeBC in the batch and column experiments. X-ray absorption near edge structure (XANES) analysis provided evidence of simultaneous oxidation and reduction of trivalent arsenic in the FeBC column experiment, accompanied by corrosive Fe oxidation. However, the addition of phosphate enhanced As stabilization, attributed to the As-incorporated Fe-Ca-phosphates precipitates. The involvement of phosphate decelerated the Fe corrosion and the formation of secondary minerals in the column, mediating the risk of passivation and clogging. The As retained by Fe-Ca-phosphate precipitates was more readily oxidized, resulting in higher proportions of pentavalent arsenic. In conclusion, the results of this work identify the corrosion control and sustained-release roles of phosphate in FeBC application, informing the perspective of FeBC in As-contaminated groundwater remediation and providing new insights into the interactions between phosphate and As.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2026

Feedforward-feedback ammonia control at a water resource recovery facility based on a digital twin with hybrid model

Ammonia-based aeration control (ABAC) at full-scale Water Resource Recovery Facilities (WRRFs) can be challenged by diurnal loading and transport delays. This work addressed these challenges using a hybrid feedforward–feedback controller built on Activated Sludge Model 1 (ASM1), marking the first full-scale deployment to pair a mechanistic feedforward core with data-driven corrections. The objectives were to improve ammonia setpoint tracking, assess performance of the mechanistic model when enhanced with data-driven corrections, and document full-scale operation. The hybrid model incorporates two data-driven components: (1) a Mechanistic Error Forecasting Engine (MEFE), consisting of a multivariate linear regressor and a long short-term memory (LSTM) ensemble. Defying expectations, low-parameter models outperformed more complex alternatives, reducing the mechanistic error by 71%. (2) A Residual Oscillation Forecasting Engine (ROFE), based on Fast Fourier Transform, reduced the remaining error by another 35%. Two proportional–integral (PI) feedback loops further (i) trim the feedforward output and (ii) eliminate residual controller error in the final aerobic zone. In full-scale operation, the controller reduced mean-squared error (MSE) by 94% over the baseline and produced more stable dissolved oxygen (DO) setpoints. Overall, it was proven that layering multi-timescale data-driven models on a mechanistic core can yield reliable ABAC performance at WRRFs.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2025

Risk of Mortality in Family Members of Men Seeking Fertility Assessment

Objective: To assess mortality in family members of men seeking fertility assessment. Subfertility serves as a biomarker for overall somatic health, and poor semen quality is associated with increased risk of hospitalization and mortality from chronic conditions. However, it is unclear if these risks extend to family members of men with low sperm count. Design: Retrospective cohort study. Subjects: Family members, up to third-degree relatives, of men in the Subfertility, Health and Assisted Reproduction and the Environment cohort who underwent a semen analysis as part of a fertility assessment 1996–2017. Relatives of men with a recorded total sperm count who lived in Utah for ≥1 year 1904–2017 were included in the analysis (N = 22,280 families). Exposure: Individuals were classified by family membership. Families were classified as relatives of azoospermic (0M), oligozoospermic (<39M), or normozoospermic (≥39M) men. The average total sperm count of the proband (male relative) with fertility assessment was also included as a continuous exposure measure. Main Outcome Measures: The main outcomes were all-cause and cause-specific mortality risk by sex, age, and degree of relation: first-, second-, and third-degree. Cox proportional hazard models were used to test the association between fertility classification and mortality, controlling for sex, race/ethnicity, and birth year. Results: A total of 666,437 relatives of men with fertility assessment (N deaths = 183,974) were included in the analysis. Relative to normozoospermia families, all-cause mortality risk increased in oligozoospermia families (hazard ratio [HR] oligozoospermia , 1.03; 95% confidence interval [CI], 1.01–1.05). Close relatives, first- (HR oligozoospermia , 1.17; 95% CI, 1.07–1.28) and second-degree relatives (HR azoospermia , 1.11; 95% CI, 1.04–1.20; HR oligozoospermia , 1.05; 95% CI,1.01–1.09), of azoospermic and oligozoospermic men had the highest all-cause and cause-specific mortality risk, including death attributed to cardiovascular disease or congenital birth conditions. Conclusion: Our results suggest that familial all-cause and cause-specific mortality risk differ by fertility phenotype. Families of azoospermic and oligozoospermic men showed significantly increased risk, particularly for close relatives. This study provides further evidence that shared genetic and/or environmental factors could influence both fertility and somatic health.

Male fertility↗
DOE OSTI2025

Benefits of Dual Fuel Heat Pump Grid-responsive Control: A Model-based Control Optimization Approach Using Building and Equipment Co-simulation

Conventional dual fuel heat pumps lack the intelligent control mechanisms to efficiently manage the switch between heat pump and furnace, leading to sub-optimal energy usage and, in some cases, increased operating costs. To resolve this gap, this study applies optimized control on hybrid heat pumps. With a focus on equipment control strategies, we compare the performances of five spacing heating equipment, including a conventional heat pump (HP), a conventional furnace, a dual fuel heat pump (DFHP) with conventional control, a dual fuel heat pump with smart control, and a novel seamlessly fuel flexible heat pump (SFFHP). While DFHP runs on either gas or electricity at any given moment, SFFHP concurrently consumes gas and electricity by continuously optimizing the proportion of each. In this research, a co-simulation framework is developed by integrating a building envelope model with a physics-based heat pump simulation model to analyze the benefits of grid-responsive controls of DFHP and SFFHP. The model-based optimal controls adjust the operation of the heat pump and gas furnace based on utility price signals and marginal grid emission to minimize utility cost and CO 2 emissions for multiple climate zones, different utility tariffs, and marginal grid emission scenarios. Case studies in Chicago and Los Angeles demonstrate that SFFHP and DFHP, with model-based optimal control, can deliver significant reductions in peak demand, utility cost, and CO 2 emission. In Chicago, SFFHP and smart controlled DFHP yield up to 64.7% and 61.7% utility cost reduction and up to 15.7% and 8.5% CO 2 emission reduction compared to the gas furnace. In Los Angeles, SFFHP and smart controlled DFHP achieve up to 43.6% and 40.1% utility cost reduction and up to 13.8% and 14.1% CO2 emission reduction compared to conventional heat pumps. In conclusion, by leveraging the fuel flexibility nature of dual fuel heat pumps, the model-based control optimization approach makes dual fuel heat pump an attractive option for demand response programs.

Control↗
DOE OSTI2025

Stereochemical Control of Water Transport Properties in Thiol‐yne Polymers

Barrier polymers underpin almost every commercial sector, yet the needs of several emerging areas remain unmet by commercially‐available materials, including temporary orthopedic implants, transient health monitors, neural implants, and other long‐term implants. The ability to tune polymer composition independently of polymer structure positions thiol‐yne click chemistry as a promising platform to serve these emerging technologies. Here, this work describes the differences in the hierarchical structure of stoichiometrically identical materials which differ only in the proportion of the cis versus trans backbone alkene stereochemistry. Varying the isomer content in this way directs different temperature and rate dependent crystallization behavior, which affords control over micron‐scale structure. This investigation focuses on how these stereochemical features affect the water vapor permeation process by several methods and develops an understanding of how this unique structural regularity improves barrier performance relative to a commercially available water barrier polymer, poly(ethylene terephthalate).

77 NANOSCIENCE AND NANOTECHNOLOGY↗
DOE OSTI2024

Efficacy and Costs of Restoring Wetland Breeding Habitat for Imperiled Amphibians in the Southeastern U.S.

Herbaceous isolated wetlands in the North American Southeastern Coastal Plain are important breeding sites for many imperiled amphibians. However, most are degraded from alterations to historic fire disturbance and hydrologic regimes. Without fire, encroaching woody vegetation can transition wetlands to more terrestrial conditions and negatively impact amphibian breeding habitat, yet few studies have experimentally tested the efficacy, cost, or temporal requirement of current methods to restore herbaceous wetland vegetation. Here, we tested the interaction of manipulating wetland canopy and leaf litter/duff to promote herbaceous vegetation within one year (i.e., one breeding season) in degraded herbaceous wetlands in South Carolina. We assessed plant response via herbaceous cover, composition, and species similarity to the wetland seed bank and then related treatment performance to treatment cost. Removing trees combined with burning, disturbing, or removing duff significantly increased herbaceous cover and proportions of wetland plants and graminoids. Removing trees alone did not improve herbaceous cover compared to closed-canopy controls, and manipulating duff alone had limited positive effects on plant cover and composition. The most expensive yet effective treatment was Tree Removal-Duff Removal, while Tree Removal-Duff Disturbance was the most cost-effective. At a minimum, we recommend removing trees and burning to kickstart herbaceous recovery. Promisingly, comparisons of our data with previous seed bank studies from these same wetlands indicate there was limited seed bank attrition during 30 years of woody encroachment. Results from this study should aid practitioners in choosing wetland restoration techniques to better conserve at-risk species in the Southeastern Coastal Plain.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2024

Tribological behavior of hybrid Aluminum-TiB 2 metal matrix composites for brake rotor applications

Here, this research investigates the feasibility of hybrid aluminum metal matrix composites (MMC) incorporating TiB 2 particles for brake rotor applications. The composites were produced by incorporating both in-situ, submicron-sized TiB 2 particles and regular micron-sized TiB 2 powders via stir and squeeze casting techniques into A206 aluminum alloy matrix. Systematic adjustments in the fractions of in-situ and ex-situ TiB 2 particles were conducted to evaluate their impact on wear behavior and mechanisms. Combination of both particle types allowed composites with up to 10 vol% of reinforcements. Composites with higher proportions of ex-situ particles demonstrated increased wear resistance compared to those solely composed of in-situ particles, control specimens without TiB 2 , and conventional cast iron counterparts. The lowest wear rate for the hybrid composites sliding against phenolic brake pads was 1.1 × 10 -5 mm 3 /Nm, signifying a 3-fold reduction relative to cast iron sliding against the same pads. Wear analysis elucidated distinctive mechanisms within the hybrid composites, characterized by mild fragmented abrasive wear, adhesive wear, and plastic deformation, accompanied by the formation of an intermixed tribo-oxide layer.

42 ENGINEERING↗
DOE OSTI2025

Descriptor: Infrastructure Perception and Control: Multi-Sensor Object Tracking Dataset (IPC-MSOT)

Traffic intersections are crucial and challenging nodes in transportation networks where multiple lanes of vehicles and pedestrians converge. Traffic accidents often occur at traffic intersections, including a large proportion of traffic fatalities and about one-half of all traffic injuries in the United States. Object detection data were collected in 2024 across three intersections in Colorado Springs, CO, USA, over the course of multiple days and various times to induce a heterogeneous mix of traffic conditions and behaviors. The purpose of the data collection exercises was to learn various attributes about infrastructure sensors and to build a repository of high-resolution, object-level data that can be used for research and development (e.g., to develop multisensor data fusion algorithms). The Infrastructure Perception and Control:Multi-Sensor Object tracking (IPC-MSOT) dataset was collected as part of the U.S. Department of Transportation's Strengthening Mobility and Revolutionizing Transportation (SMART) project, where the city of Colorado Springs, Colorado, and the National Renewable Energy Laboratory collaborated to collect object-level trajectory data from road users using multiple types of infrastructure sensors deployed at different intersections. This dataset allows for testing of late-stage sensor fusion algorithms and their ability to ingest multimodal sensor data, and it can be utilized by traffic engineers to design and evaluate trajectory-based signal control strategies.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2025

Roles of surface Mn(III) and MgOH + /CaOH + complexation in photochemically assisted Mn 2+ oxidation and Todorokite formation

Todorokite, a Mn oxide phase commonly found in seafloor Mn nodules, is one of the most abundant Mn oxides in nature and has wide applications in environmental engineering, including heavy metal remediation, contaminant adsorption for water purification, and catalysis for organic pollutant degradation. However, traditional abiotic formation of todorokite reported to date typically requires high temperature, pressure, and pH outside circumneutral conditions, or involves several days of phase transformations from precursor phases. In this study, we demonstrate rapid todorokite formation within 6 h via photochemically assisted oxidation of Mn 2+ (aq) in the presence of Mg 2+ or Ca 2+ , notably at ambient temperature and pressure. The concentrations of aqueous MgOH + and CaOH + , as well as the pH (initial 9 or 6), had significant collective influences on the crystalline phases of the formed Mn oxide solids. The proportions of the Mn oxidation states (IV, III, and II) and the extent of Mn(III) surface complexation with MgOH + or CaOH + controlled the crystalline phases (todorokite, feitknechtite, and birnessite) and the extent of cation incorporation into the resulting Mn oxide solids. Specifically, the oxidation state of Mn influenced the crystallization of different Mn oxide phases, and the formed Mn(III) complexed with MgOH + or CaOH + facilitated the formation of todorokite, along with cation incorporation. X-ray pair distribution function analysis revealed that incorporated Mg species were located at the inside corner sites of the 5 × 3 MnO 6 octahedral tunnel structure of todorokite, suggesting complexation between MgOH + and Mn(III) at the corners of the tunnel. Furthermore, this study provides novel insights into the elusive formation of todorokite and its potential for applications in advanced water treatment and environmental remediation.

Abiotic Mn2+ oxidation↗
DOE OSTI2024

Dynamic Shaping of Grid Response of Multi-Machine Multi-Inverter Systems Through Grid-Forming IBRs

We consider the problem of controlling the frequency response of weakly-coupled multi-machine multi-inverter low-inertia power systems via grid-forming inverter-based resources (IBRs). In contrast to existing methods, our approach relies on dividing the larger system into multiple strongly-coupled subsystems, without ignoring either the underlying network or approximating the subsystem response as an aggregate harmonic mean model. Rather, through a structured clustering and recursive dynamic shaping approach, the frequency response of the overall system to load perturbations is shaped appropriately. We demonstrate the proposed approach for a three-node triangular configuration and a small-scale radial network. Furthermore, previous synchronization analysis for heterogeneous systems requires the machines to satisfy certain proportionality property. In our approach, the effective transfer functions for each cluster can be tuned by the IBRs to satisfy such property, enabling us to apply the shaping control to systems with a wider range of heterogeneous machines.

frequency-shaping control↗
DOE OSTI2026

Quantum-Enhanced Dark-Matter Sensing with Large Photon Number Fock States in a High-Q SRF Cavity

Wave-like dark matter candidates such as axions or dark photons in the microwave frequency range can be probed using resonant superconducting cavities. We demonstrate a quantum-enhanced sensing approach based on a multimode, high-Q superconducting RF (SRF) cavity, where a large Fock state is prepared in the storage mode via sideband transitions mediated by a transmon ancilla and a measurement-based feedforward protocol, achieving high-fidelity Fock states [1]. The prepared |n⟩ state induces stimulated emission from the dark-matter field, providing an (n + 1) enhancement in transition probability and proportional boost in signal rate [2]. A secondary cavity mode functions as an in-situ reference to calibrate noise. We present the control sequence, noise-referencing strategy, and projected sensitivity improvements for axion and dark-photon detection. This multimode architecture combines large Fock state preparation with noise calibration, offering a practical path to increased scan rate in cavity-based dark-matter searches.

Kim, Taeyoon↗
DOE OSTI2024

Dynamic Shaping of Grid Response of Multi-Machine Multi-Inverter Systems Through Grid-Forming IBRs: Preprint

We consider the problem of controlling the frequency response of weakly-coupled multi-machine multi-inverter low-inertia power systems via grid-forming inverter-based resources (IBRs). In contrast to existing methods, our approach relies on dividing the larger system into multiple strongly-coupled subsystems, without ignoring either the underlying network or approximating the subsystem response as an aggregate harmonic mean model. Rather, through a structured clustering and recursive dynamic shaping approach, the frequency response of the overall system to load perturbations is shaped appropriately. We demonstrate the proposed approach for a three-node triangular configuration and a small-scale radial network. Furthermore, for small-scale radial microgrids, we demonstrate the ability of IBRs to tune the effective transfer functions of synchronous machines. This enables us to relax the uniform turbine time-constant assumptions and widen the scope of existing synchronization results for proportionally heterogeneous machines.

frequency-shaping control↗
DOE OSTI2024

Evolution of oxygen and stratification and their relationship in the North Pacific Ocean in CMIP6 Earth system models

Abstract. This study examines the linkages between the upper-ocean (0–200 m) oxygen (O2) content and stratification in the North Pacific Ocean using four Earth system models (ESMs), an ocean hindcast simulation, and an ocean reanalysis. The trends and variability in oceanic O2 content are driven by the imbalance between physical supply and biological demand. Physical supply is primarily controlled by ocean ventilation, which is responsible for the transport of O2-rich surface waters to the subsurface. Isopycnic potential vorticity (IPV), a quasi-conservative tracer proportional to density stratification that can be evaluated from temperature and salinity measurements, is used herein as a dynamical proxy for ocean ventilation. The predictability potential of the IPV field is evaluated through its information entropy. The results highlight a strong O2–IPV connection and somewhat higher (as compared to the rest of the basin) predictability potential for IPV across the tropical Pacific, where the El Niño–Southern Oscillation occurs. This pattern of higher predictability and strong anticorrelation between O2 and stratification is robust across multiple models and datasets. In contrast, IPV at mid-latitudes has low predictability potential and its center of action differs from that of O2. In addition, the locations of extreme events or hotspots may or may not differ between the two fields, with a strong model dependency, which persists in future projections. On the one hand, these results suggest that it may be possible to monitor ocean O2 in the tropical Pacific based on a few observational sites co-located with the more abundant IPV measurements; on the other, they lead us to question the robustness of the IPV–O2 relationship in the extratropics. The proposed framework helps to characterize and interpret O2 variability in relation to physical variability and may be especially useful in the analysis of new observation-based data products derived from the BGC-Argo float array in combination with the traditional but far more abundant Argo data.

Novi, Lyuba↗
DOE OSTI2026

Identification of drug repurposing candidates for amyotrophic lateral sclerosis using electronic health records: a retrospective cohort study

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease with a life expectancy of only 3–5 years and few approved treatments. To identify drug repurposing candidates for the treatment of ALS, we analysed the electronic health records (EHRs) of a large cohort of military veterans with ALS. We analysed the EHRs of individuals in the US Veterans Health Administration (VHA) database who were diagnosed with ALS between Jan 1, 2009 and Dec 31, 2019 to assess medication effects. Individuals without recorded prescriptions after the date of diagnosis were excluded. Two sets of criteria were applied to ascertain exposure. Exposure criteria A were met if the dispense date or the end date of the medication was within 12 months of ALS diagnosis and the end date was at least 6 months after the dispense date. Exposure criteria B were met if there were at least two dispenses within 6 months before diagnosis and 12 months after diagnosis. Propensity score-matched control groups were generated on the basis of confounders included in the EHR, with methodology of potential outcomes used to infer treatment effects. The primary outcome was death. A standard Cox proportional hazards analysis was done to assess association with survival. Survival was defined as the time from diagnosis date recorded in the EHR to death reported in the Department for Veterans Affairs Vital Status File. Follow-up survival time was censored on Dec 31, 2020, for those alive on this date. Downstream protein targets of drugs with clinically significant effects were analysed using the protein–protein interaction networks-based algorithm PathFX. The EHRs of 11 003 individuals with ALS in the VHA database were appropriate for analysis. 162 medications with treatment groups of 30 or more individuals were identified. Among these 162 medications, 27 were associated with statistically significant changes (≥0·1) in the hazard ratio (HR) for death. 18 of the medications were associated with a reduced HR for death (prolonged survival), and nine were associated with an increased HR for death (reduced survival). Drugs associated with reduced HR included HMG-CoA reductase inhibitors (simvastatin, pravastatin, lovastatin, and atorvastatin), PDE5 inhibitors (vardenafil and sildenafil), and α-adrenergic antagonists (tamsulosin and terazosin). The medications associated with an increased HR were drugs used either in the management of clinical features of ALS associated with poor outcomes or in end-of-life care. PathFx analysis identified a complex of proteins interacting with several of the identified drugs. To our knowledge, this analysis is the largest EHR-based study for identifying drug repurposing candidates for ALS. We identified several drugs that warrant further assessment as therapeutic options in ALS, as well as a protein network complex that might serve as a therapeutic target for ALS.

Reimer, Richard J. [Stanford Univ., CA (United Sta↗