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DOE OSTI2024

Characterizing risk for Dengue in Brazil: a multi-dimensional approach

Dengue is the most common mosquito-borne infectious disease worldwide, primarily caused by the Aedes Aegypti mosquitoes. There are approximately 100-400 million cases annually, with roughly half of the global population at risk. In recent years, and particularly in 2024, there has been a major increase in Dengue cases in North and South America. One of the most heavily affected countries is Brazil, where there has been a 230% increase in cases in 2024 compared to 2023. In a report in June 2024, the CDC released a report indicating 3 risk groups for dengue: infants aged ≤1 year, pregnant women, and adults over 65 years old. Due to the spike in cases, it’s important to understand what factors contribute to Dengue risk and create a model to quantify it in order to inform decisions on how to respond. The main 2 parts of this project were a) exploring the spatial relationships between these 3 Dengue risk group populations and aedes aegypti mosquitoes in Brazil and b) creating an index to quantify risk for Dengue in Brazil. The 10 cities with the highest risk were identified, and it was found that the east coast and southern regions are at highest risk. The findings in this study provide insights into cities and areas of Brazil that should be focused on for targeting Dengue spread.

59 BASIC BIOLOGICAL SCIENCES↗

DOE OSTI2023

COVID-19 vaccination status, side effects, and perceptions among breast cancer survivors: a cross-sectional study in China

Introduction Breast cancer is the most prevalent malignancy in patients with coronavirus disease 2019 (COVID-19). However, vaccination data of this population are limited. Methods A cross-sectional study of COVID-19 vaccination was conducted in China. Multivariate logistic regression models were used to assess factors associated with COVID-19 vaccination status. Results Of 2,904 participants, 50.2% were vaccinated with acceptable side effects. Most of the participants received inactivated virus vaccines. The most common reason for vaccination was “fear of infection” (56.2%) and “workplace/government requirement” (33.1%). While the most common reason for nonvaccination was “worry that vaccines cause breast cancer progression or interfere with treatment” (72.9%) and “have concerns about side effects or safety” (39.6%). Patients who were employed (odds ratio, OR = 1.783, p = 0.015), had stage I disease at diagnosis (OR = 2.008, p = 0.019), thought vaccines could provide protection (OR = 1.774, p = 0.007), thought COVID-19 vaccines were safe, very safe, not safe, and very unsafe (OR = 2.074, p < 0.001; OR = 4.251, p < 0.001; OR = 2.075, p = 0.011; OR = 5.609, p = 0.003, respectively) were more likely to receive vaccination. Patients who were 1–3 years, 3–5 years, and more than 5 years after surgery (OR = 0.277, p < 0.001; OR = 0.277, p < 0.001, OR = 0.282, p < 0.001, respectively), had a history of food or drug allergies (OR = 0.579, p = 0.001), had recently undergone endocrine therapy (OR = 0.531, p < 0.001) were less likely to receive vaccination. Conclusion COVID-19 vaccination gap exists in breast cancer survivors, which could be filled by raising awareness and increasing confidence in vaccine safety during cancer treatment, particularly for the unemployed individuals.

Xu, Yali↗

DOE OSTI2024

Integrated transcriptomic and metabolomic investigation of the genes and metabolites involved in swine follicular cyst formation

Follicular cysts are a common reproductive disorder in mammals that is usually caused by stress. However, the pathogenesis of follicular cysts in sows remains unclear. To provide new insights into the mechanisms of follicular cyst formation in pigs, we conducted a combined transcriptomic and metabolomic analysis on theca interna and mural granulosa cells of follicular cysts and mature follicles. We identified 2,533 up-regulated and 1,355 down-regulated genes in follicular cysts, compared with mature follicles. These differentially expressed genes were mainly found in signaling pathways related to tumor formation and cortisol synthesis and secretion as shown by Ingenuity Pathway Analysis, which predicted 4,362 upstream regulatory factors. The combined gene expression and pathway analysis identified the following genes as potential biomarkers for porcine follicular cysts: cytochrome P450 family 2 subfamily C polypeptide 18, L-lactate dehydrogenase, carbamoyl-phosphate synthase, fibroblast growth factor 7, integrin binding sialoprotein, interleukin 23 receptor, prolactin receptor, epiregulin, interleukin 1 receptor type II, arginine vasopressin receptor 1A, fibroblast growth factor 10, claudin 7, G Protein Subunit Gamma 3, cholecystokinin B receptor and cytosolic phospholipase A2 . Metabolomics analysis found significant differences in 87 metabolites, which were enriched in unsaturated fatty acid biosynthesis, and sphingolipid signaling pathways. These results provide valuable information on the molecular mechanisms of follicular cyst formation, which may facilitate the development of new therapeutics to prevent and treat follicular cysts.

Dai, Jiage↗

DOE OSTI2020

Genotypic and Phenotypic Characterization of Incompatibility Group FIB Positive Salmonella enterica Serovar Typhimurium Isolates from Food Animal Sources

Salmonella enterica is one of the most common bacterial foodborne pathogens in the United States, causing illnesses that range from self-limiting gastroenteritis to more severe, life threatening invasive disease. Many Salmonella strains contain plasmids that carry virulence, antimicrobial resistance, and/or transfer genes which allow them to adapt to diverse environments, and these can include incompatibility group (Inc) FIB plasmids. This study was undertaken to evaluate the genomic and phenotypic characteristics of IncFIB-positive Salmonella enterica serovar Typhimurium isolates from food animal sources, to identify their plasmid content, assess antimicrobial resistance and virulence properties, and compare their genotypic isolates with more recently isolated S. Typhimurium isolates from food animal sources. Methods: We identified 71 S. Typhimurium isolates that carried IncFIB plasmids. These isolates were subjected to whole genome sequencing and evaluated for bacteriocin production, antimicrobial susceptibility, the ability to transfer resistance plasmids, and a subset was evaluated for their ability to invade and persist in intestinal human epithelial cells. Results: Approximately 30% of isolates (n = 21) displayed bacteriocin inhibition of Escherichia coli strain J53. Bioinformatic analyses using PlasmidFinder software confirmed that all isolates contained IncFIB plasmids along with multiple other plasmid replicon types. Comparative analyses showed that all strains carried multiple antimicrobial resistance genes and virulence factors including iron acquisition genes, such as iucABCD (75%), iutA (94%), sitABCD (76%) and sitAB (100%). In 17 cases (71%), IncFIB plasmids, along with other plasmid replicon types, were able to conjugally transfer antimicrobial resistance and virulence genes to the susceptible recipient strain. For ten strains, persistence cell counts (27%) were noted to be significantly higher than invasion bacterial cell counts. When the genome sequences of the study isolates collected from 1998–2003 were compared to those published from subsequent years (2005–2018), overlapping genotypes were found, indicating the perseverance of IncFIB positive strains in food animal populations. This study confirms that IncFIB plasmids can play a potential role in disseminating antimicrobial resistance and virulence genes amongst bacteria from several food animal species.

59 BASIC BIOLOGICAL SCIENCES↗

DOE OSTI2021

Impact of Aerosol and Cloud on the Solar Energy Potential over the Central Gangetic Himalayan Region

We examine the impact of atmospheric aerosols and clouds on the surface solar radiation and solar energy at Nainital, a high-altitude remote location in the central Gangetic Himalayan region (CGHR). For this purpose, we exploited the synergy of remote-sensed data in terms of ground-based AERONET Sun Photometer and satellite observations from the MODerate Resolution Imaging Spectroradiometer (MODIS) and the Meteosat Second Generation (MSG), with radiative transfer model (RTM) simulations and 1 day forecasts from the Copernicus Atmosphere Monitoring Service (CAMS). Clouds and aerosols are one of the most common sources of solar irradiance attenuation and hence causing performance issues in the photovoltaic (PV) and concentrated solar power (CSP) plant installations. The outputs of RTM results presented with high accuracy under clear, cloudy sky and dust conditions for global horizontal (GHI) and beam horizontal irradiance (BHI). On an annual basis the total aerosol attenuation was found to be up to 105 kWh m –2 for the GHI and 266 kWh m –2 for BHI, respectively, while the cloud effect is much stronger with an attenuation of 245 and 271 kWh m –2 on GHI and BHI. The results of this study will support the Indian solar energy producers and electricity handling entities in order to quantify the energy and financial losses due to cloud and aerosol presence.

54 ENVIRONMENTAL SCIENCES↗

DOE OSTI2020

Accelerated Aging Humidity Chamber for Nuclear Grade HEPA Filter Media

A unique accelerated aging humidity chamber for simulating the natural aging process of nuclear grade high efficiency particulate air (HEPA) filter media is being designed, implemented, and tested. The nuclear industry currently lacks information regarding the shelf life and service life of HEPA filter media. The Department of Energy recommends disposing of HEPA filters 10 years after the manufacture date for filters operated under dry conditions. Studies have shown the tensile strength and water repellency of HEPA filter media diminish with age. The chamber's principal function is to sustain an elevated relative humidity condition for an extended duration specified by the Arrhenius aging model. To accomplish this, various design parameters were established: (1) consistently achieve uniform humidity conditions within the chamber to equally expose media sheets, (2) ensure the chamber is sufficiently sealed to mitigate the uncontrolled infiltration of air, (3) confidently secure the media sheets to avert the introduction of unnecessary stressing/creasing, (4) fabricate the chamber from clear polycarbonate material to allow inspection of the media sheets, (5) provide a safe and ergonomic design for personnel, (6) ensure the chamber design is replicable and relatively easy to fabricate/assemble. A humidity source, fan, PID controller, humidity and temperature transmitters, and data loggers are required for proper operation and control of the chamber. The humidity source must accommodate target values up to 95% relative humidity throughout the chamber. The three humidity and temperature transmitters are strategically spaced throughout the chamber to ensure uniform conditions. The 10 cubic feet per minute (CFM) fan selected intends to accomplish the desired air change rate inside the chamber of approximately 20 air changes per hour (ACH). The 2 plenums on the upper and lower portions of the chamber utilize a perforated design to uniformly distribute air, promote air mixing, and control the air velocity entering the chamber. Industrial blueprint hanging clamps are being retrofitted to be seated within the chamber drawers and firmly secure the nuclear grade filter media. The aged media will be evaluated using autopsy methodology, and the results obtained intend to help clarify the useful life of nuclear grade HEPA filters. Nuclear grade high efficiency particulate air (HEPA) filters are defined as disposable, extended-media, dry-type filters with a rigid casing enclosing the full depth of the pleats and have a minimum particle removal efficiency of 99.97%. [1] - HEPA filters are constantly exposed to stressors and subsequently have been shown to degrade as the filter ages. Properties such as tensile strength and water repellency, along with others, are negatively impacted. [2] - Due to the scarcity of naturally aged HEPA filters available, it is crucial to develop accelerated aging methods which effectively mimic the natural degradation effects. - After accelerated aging, the filters are subject to testing in the Axial Flow Large Scale Test Stand (ALSTS) and other analysis techniques such as the same qualification tests performed directly after being manufactured. - Quality data is necessary for future decisions regarding the lifetime of nuclear grade HEPA filters. - The objective is to develop a prototype accelerated aging humidity chamber for nuclear grade HEPA filter media. The chamber should expose the media to commonly occurring stressors to expedite the degradation process caused by aging. PID yields reliable and reproducible results: - CFD model correlates well with actual performance; - Further analysis is needed to complete characterization; - Future work for the chamber is still to be completed. The data shown in Figure 5 and Table 1 indicate the system is functioning as designed. As can be determined from the system response evaluation in Table 1, the PID controller is yielding reliable and reproducible results at each set point. As the set point increases, the time constant and 20% settling time increase accordingly. From the results in Table 1, it stands to reason that the CFD model correlates well with the actual performance of the system. Each system response parameter for the 90%RH* CFD model is slightly lower than the parameters collected from the physical model tested at an equivalent set point. This is to be expected considering the inlet in the CFD model is a constant supply of water vapor, whereas the physical model uses a PID controller to monitor the amount of water vapor needed and reacts accordingly. More analysis is still to be done on the prototype chamber. A pressure test will be conducted in order to determine the hourly leak rate of the chamber. This test will involve constant air flow into the chamber until the desired pressure is reached. A uniformity test will also be conducted in order to ensure each filter medium is being exposed to equivalent relative humidity levels. This test will involve an array of humidity meters strategically oriented inside the chamber to record any possible gradients. Future work for the chamber includes dehumidification abilities, tests while fully loaded with filters, and temperature control. Once completed, the autopsy team at Institute of Clean Energy Technology will conduct necessary accelerated aging studies as needed.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

DOE OSTI2024

Analysis of the Surface Morphology and Chemical Composition of Zr-Nb3Sn Alloys with Different Zr Concentrations

In the field of superconducting science, Nb has been the material of choice for Radio Frequency (RF) Cavities for years. However, in recent years Nb3Sn has shown to be a promising alternative to Nb. Its combination of a significantly high superconducting transition temperature and a much higher value of upper critical magnetic field (Hc2), has been the reason the alloy has been so widely studied. This project aims to develop materials to further improve the high magnetic field performance of Nb3Sn by improving its upper critical magnetic field and critical current density (Jc). One way to improve the Jc and the Hc2 is to create more grain boundaries in the Nb3Sn alloy allowing them to trap more magnetic flux lines in the materials. To do this the grains must be made smaller which will naturally cause the formation of more grain boundaries. A common way to create smaller grains is by doping an impurity in the alloy. In this study, Nb3Sn was doped with Zr to form Zr-Nb3Sn alloys. This project investigates the surface properties and chemical composition of Zr-Nb3Sn alloys with varying zirconium concentrations (~0.5% and ~24% Zr). Using Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS), and X-ray Photoemission Spectroscopy (XPS), allowed for the characterization of the differences in surface morphology and elemental composition between samples. SEM images were quantified using ImageJ giving insight into grain distribution. The results indicate that increased Zr concentration creates smaller grains in the Zr-Nb3Sn alloy. Furthermore, the ~ 24% Zr grew nanoscale particles on the surface that are possible oxides. XPS data revealed that as Zr concentration increased, the total Nb oxides (NbOx) thickness decreased. Conversely, as Zr concentration increased, the surface Sn oxides (SnOx) also increased slightly. Quantification via ImageJ of SEM data showed that the ~ 0.5% Zr sample had a grain size of ~ 5300 nm2. These results show that Zr inclusion leads to smaller grain formations, which is promising in the world of superconducting RF cavities for high magnetic field applications.

Sue, Micah↗

DOE OSTI2024

Novel mutation leading to splice donor loss in a conserved site of DMD gene causes Duchenne muscular dystrophy with cryptorchidism

Background As one of the most common congenital abnormalities in male births, cryptorchidism has been found to have a polygenic aetiology according to previous studies of common variants. However, little is known about genetic predisposition of rare variants for cryptorchidism, since rare variants have larger effective size on diseases than common variants. Methods In this study, a cohort of 115 Chinese probands with cryptorchidism was analysed using whole-genome sequencing, alongside 19 parental controls and 2136 unaffected men. Additionally, CRISPR-Cas9 editing of a conserved variant was performed in a mouse model, with MRI screening used to observe the phenotype. Results In 30 of 115 patients (26.1%), we identified four novel genes ( ARSH , DMD , MAGEA4 and SHROOM2 ) affecting at least five unrelated patients and four known genes ( USP9Y , UBA1 , BCORL1 and KDM6A ) with the candidate rare pathogenic variants affecting at least two cases. Burden tests of rare variants revealed the genome-wide significances for newly identified genes (p<2.5×10 −6 ) under the Bonferroni correction. Surprisingly, novel and known genes were mainly found on X chromosome (seven on X and one on Y) and all rare X-chromosomal segregating variants exhibited a maternal inheritance rather than de novo origin. CRISPR-Cas9 mouse modelling of a splice donor loss variant in DMD (NC_000023.11:g.32454661C>G), which resides in a conserved site across vertebrates, replicated bilateral cryptorchidism phenotypes, confirmed by MRI at 4 and 10 weeks. The movement tests further revealed symptoms of Duchenne muscular dystrophy (DMD) in transgenic mice. Conclusion Our results revealed the role of the DMD gene mutation in causing cryptorchidism. The results also suggest that maternal-X inheritance of pathogenic defects could have a predominant role in the development of cryptorchidism.

Chen, Jianhai (ORCID:0000000300932003)↗

DOE OSTI2021

Pre-existing humoral immunity to human common cold coronaviruses negatively impacts the protective SARS-CoV-2 antibody response

SARS-CoV-2 infection causes diverse outcomes ranging from asymptomatic infection to respiratory distress and death. A major unresolved question is whether prior immunity to endemic, human common cold coronaviruses (hCCCoVs) impacts susceptibility to SARS-CoV-2 infection or immunity following infection and vaccination. Therefore, we analyzed samples from the same individuals before and after SARS-CoV-2 infection or vaccination. We found hCCCoV antibody levels increase after SARS-CoV-2 exposure, demonstrating cross-reactivity. However, a case-control study indicates that baseline hCCCoV antibody levels are not associated with protection against SARS-CoV-2 infection. Rather, higher magnitudes of pre-existing betacoronavirus antibodies correlate with more SARS-CoV-2 antibodies following infection, an indicator of greater disease severity. Additionally, immunization with hCCCoV spike proteins before SARS-CoV-2 immunization impedes the generation of SARS-CoV-2-neutralizing antibodies in mice. Together, these data suggest that pre-existing hCCCoV antibodies hinder SARS-CoV-2 antibody-based immunity following infection and provide insight on how pre-existing coronavirus immunity impacts SARS-CoV-2 infection, which is critical considering emerging variants.

60 APPLIED LIFE SCIENCES↗

DOE OSTI2023

Autonomous Inversion of In Situ Deformation Measurement Data for Injection-Induced Stress Change

Geologic carbon storage (GCS) is likely to play a key part of the global effort to dramatically reduce CO2 emissions and perhaps even reduce atmospheric CO2 concentrations through carbon negative operations. A critical part of effort to commercialize and widely deploy this technology is developing the capability to rapidly assimilate real-time monitoring data into a form that will enable site operators to make decisions to manage the safe and efficient operations. Two of the risks associate with GCS are the risk of inducing fractures in the sealing formations that can create leakage pathways and the risk of inducing earthquakes of sufficient magnitude to cause public concern, property damage, or safety risks. To properly manage these risks the site operator needs to know the initial state of stress, the change in stress induced by injection, and the relationship between operational parameters such as injection rate and pressure and the change in stress. Current methods of estimating the change in stress require choosing the type of constitutive model and the model parameters based on core, log, and geophysical data during the characterization phase, with little feedback from operational observations to validate or refine these choices. These characterization methods interrogate the geologic formations using length scales, loading rates or magnitudes that are quite different from those encountered by the actual storage system. It is shown that errors in the assumed constitutive response, even when informed by laboratory tests on core samples, are likely to be common, large, and underestimate the magnitude of stress change caused by injection. Recent advances in borehole-based strain instruments and borehole and surface-based tilt and displacement instruments have now enabled monitoring of the deformation of the storage system throughout its operational lifespan. This data can enable validation and refinement of the knowledge of the geomechanical properties and state of the system, but brings with it a challenge to transform the raw data into actionable knowledge. We demonstrate a method that uses automatic differentiation and a finite-element based geomechanical model perform a gradient-based deterministic inversion of geomechanical monitoring data. This approach allows autonomous integration of the instrument data without the need for time consuming manual interpretation and selection of updated model parameters. Furthermore, only isotropic linear elasticity is considered in this paper, the approach presented is very flexible as to what type of geomechanical constitutive response can be used. The approach is easily adaptable to nonlinear physics-based constitutive models to account for common rock behaviors such as creep and plasticity. The approach also enables training of machine learning-based constitutive models by allowing back propagation of errors through the finite element calculations. This enables strongly enforcing known physics, such as conservation of momentum and continuity, while allowing data-driven models to learn the truly unknown physics such as the constitutive or petrophysical responses.

Burghardt, Jeffrey A.↗

DOE OSTI2024

No evidence of Bartonella infections in host-seeking Ixodes scapularis and Ixodes pacificus ticks in the United States

Background. Bartonella spp. infect a variety of vertebrates throughout the world, with generally high prevalence. Several Bartonella spp. are known to cause diverse clinical manifestations in humans and have been recognized as emerging pathogens. These bacteria are mainly transmitted by blood-sucking arthropods, such as fleas and lice. The role of ticks in the transmission of Bartonella spp. is unclear. Methods. A recently developed quadruplex polymerase chain reaction (PCR) amplicon next-generation sequencing approach that targets Bartonella-specific fragments on gltA, ssrA, rpoB, and groEL was applied to test host-seeking Ixodes scapularis ticks (n=1641; consisting of 886 nymphs and 755 adults) collected in 23 states of the eastern half of the United States and Ixodes pacificus ticks (n=966; all nymphs) collected in California in the western United States for the presence of Bartonella DNA. These species were selected because they are common human biters and serve as vectors of pathogens causing the greatest number of vector-borne diseases in the United States. Results. No Bartonella DNA was detected in any of the ticks tested by any target. Conclusions. Owing to the lack of Bartonella detection in a large number of host-seeking Ixodes spp. ticks tested across a broad geographical region, our results strongly suggest that I. scapularis and I. pacificus are unlikely to contribute more than minimally, if at all, to the transmission of Bartonella spp.

59 BASIC BIOLOGICAL SCIENCES↗

DOE OSTI2020

Quantum dynamics in strongly driven random dipolar magnets

The random dipolar magnet LiHo x Y 1– x F 4 enters a strongly frustrated regime for small Ho 3+ concentrations with x < 0.05. In this regime, the magnetic moments of the Ho 3+ ions experience small quantum corrections to the common Ising approximation of LiHo x Y 1– x F 4 , which lead to a $\mathbb{Z}_2$-symmetry breaking and small, degeneracy breaking energy shifts between different eigenstates. Here we show that destructive interference between two almost degenerate excitation pathways burns spectral holes in the magnetic susceptibility of strongly driven magnetic moments in LiHo x Y 1– x F 4 . Such spectral holes in the susceptibility, microscopically described in terms of Fano resonances, can already occur in setups of only two or three frustrated moments, for which the driven level scheme has the paradigmatic Λ shape. For larger clusters of magnetic moments, the corresponding level schemes separate into almost isolated many-body Λ schemes, in the sense that either the transition matrix elements between them are negligibly small or the energy difference of the transitions is strongly off-resonant to the drive. This enables the observation of Fano resonances, caused by many-body quantum corrections to the common Ising approximation also in the thermodynamic limit. Finally, we discuss its dependence on the driving strength and frequency as well as the crucial role that is played by lattice dissipation.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗

DOE OSTI2020

Epidemiological surveillance of common respiratory viruses in patients with suspected COVID-19 in Southwest China

Abstract Background The outbreak of coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is currently the peak season of common respiratory viral infections. However, the clinical symptoms of most SARS-CoV-2 infected patients are not significantly different from those of common respiratory viral infections. Therefore, knowing the epidemiological patterns of common respiratory viruses may be valuable to improve the diagnostic and therapeutic efficacy of patients with suspected COVID-19, especially in Southwest China (a mild epidemic area). Methods A total of 2188 patients with clinically suspected of COVID-19 in Southwest China were recruited from January 21 to February 29, 2020. Nasopharyngeal swabs, throat swabs and sputum specimens were collected to detect SARS-CoV-2 by using real-time reverse transcription-polymerase chain reaction (RT-PCR) and other 12 viruses via PCR fragment analysis combined with capillary electrophoresis. Clinical characteristics and laboratory test findings were acquired from electronic medical records. All data were analyzed to unravel the epidemiological patterns. Results Only 1.1% (24/2188) patients with suspected COVID-19 were eventually confirmed to have SARS-CoV-2 infection, and the most frequently observed symptoms were fever (75.0%, 18/24) and cough (20.8%, 5/24). The overall detection rate of other respiratory pathogens was 10.3% (226/2188). Among them, human rhinovirus (3.2%, 71/2188), human parainfluenza viruses (1.6%, 35/2188), influenza B virus (1.2%, 26/2188) and mycoplasma pneumonia (1.2%, 26/2188) were the predominantly detected pathogens in this study. Moreover, the co-infection was observed in 22 specimens. Notably, one COVID-19 case had a coexisting infection with human parainfluenza virus (4.2%, 1/24) and bocavirus was the most common virus tending to occur in co-infection with other respiratory pathogens. Conclusions This study reveals the epidemiological features of common respiratory viruses and their clinical impact during the ongoing outbreak of COVID-19 in a mild epidemic area. The findings highlight the importance of understanding the transmission patterns of the common respiratory virus in COVID-19 regions, which can provide information support for the development of appropriate treatment plans and health policies, while eliminating unnecessary fear and tension.

Si, Yanjun↗

DOE OSTI2021

TRIM27-mediated ubiquitination of PPARγ promotes glutamate-induced cell apoptosis and inflammation

Neurotoxicity induced by glutamate (Glu) is often used to study the signaling mechanism of neurological disorders. The identification of specific genetic factors that cause Glu-induced neurotoxicity provides evidence for the common pathways of neuronal apoptosis and inflammation. TRIM27 has been found to induce apoptosis and inflammation. Nevertheless, there is little evidence that TRIM27 is associated with Glu-induced neurotoxicity. We found that TRIM27 expression was increased in epilepsy patients and in HT22 cells following Glu treatment. Glu-mediated cell apoptosis, decreased PPARγ expression, and increased levels of cleaved Caspase-3 and IL-1β expression in HT22 cells were significantly inhibited by TRIM27 knockdown. TRIM27 overexpression significantly induced cell apoptosis and expression of cleaved Caspase-3 and IL-1β, but inhibited PPARγ expression in HT22 cells, which were reversed by ROZ, suggesting the involvement of PPARγ in TRIM27-mediated cell apoptosis and inflammation in HT22 cells. Mechanically, TRIM27 ubiquitinates and degrades PPARγ, following induces cleaved Caspase-3 and IL-1β expression. Clinically, increased expression of TRIM27 in epilepsy patients was associated with decreased PPARγ expression. Taken together, our study suggests that TRIM27-mediated ubiquitination of PPARγ promotes Glu-induced HT22 cell apoptosis and IL-1β release.

60 APPLIED LIFE SCIENCES↗

DOE OSTI2025

Cyanine-Incorporated Amorphous Polymeric Carbon Dots for Optical Reactive Oxygen Species Sensing

Reactive oxygen species (ROS) are common cellular oxidants that when overproduced by cellular stressors cause harm to cells. Detection of ROS is of utmost importance to understanding a wide variety of cellular function and toxicity mechanisms. Conventional ROS fluorescence assays involve using a single dye to visualize the ROS quantity. Herein, we describe ROS-sensitive, fluorescent-dye-incorporated carbon dots with dual fluorescence capabilities and good biocompatibility. Carbon dots (CDs) made of citric acid and urea were synthesized with incorporated cyanine-3-amine (Cy3), a bright red fluorescent dye, to create Cy3-CDs. Additionally, to get Cy3 into the ROS-sensitive form, this work demonstrated that Cy3 alone and Cy3 within carbon dots can be electrochemically reduced to their colorless ROS-sensitive form. Cy3, CDs, and Cy3-CDs are all responsive to additions of superoxide, leading to an increase in the fluorescence. Overall, this work examines how O 2 •– and additional oxidizers interact with CDs, Cy3, and Cy3-CDs, and molecular-level hypotheses are explored that will inform the design of future carbon dot-based ROS sensors.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

DOE OSTI2020

Alcohol-Induced Low-Temperature Blockage of Supported-Metal Catalysts for Enhanced Catalysis

The partial or complete blockage of active sites of metal nanoparticles (NPs) on supported-metal catalysts has been of interest for tuning the stability, selectivity, and rate of reactions. In this study, we show that Au-sites in Au/TiO 2 surprisingly become blocked upon treatment in common alcohols (2-propanol and methanol), with 2-propanol causing a greater extent of blockage. Nearly 95% of Au-sites are covered after treatment in 2-propanol at room temperature, followed by desorption at 150 °C. Infrared spectroscopy of CO adsorption unambiguously confirms the occurrence of this phenomenon. Electron energy loss spectroscopy (EELS), temperature-programmed desorption (TPD), Raman spectroscopy, and DFT simulations suggest that the formation of carbon deposits from 2-propanol decomposition and/or the migration of a TiO x layer over the supported NPs may be responsible for the blockage of Au-sites. Nearly full coverage of Au NPs after treatment in 2-propanol led to negligible activity for catalytic CO oxidation, whereas partial retraction of the overlayer led to enhanced activity with time-on-stream, suggesting a self-activating catalytic performance.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

DOE OSTI2025

Population Genomics of Pseudocercospora griseola Reveals New Groups in the Middle American Clade and the Presence of the Endophytic Bacterium Achromobacter xylosoxidans

Angular leaf spot (ALS), caused by Pseudocercospora griseola is an important disease of common beans. P. griseola, is highly variable and has co-evolved with its host. In this study, 48 isolates of P. griseola from Puerto Rico, Guatemala, Honduras and Tanzania were sequenced (3RADseq), resulting in the de novo assembly of 42,214 contigs. Phylogenomic, population genetic structure and principal component analyses using 1,260 SNPs divided these isolates into two populations, Andean and Middle American, while the Middle American population was further divided into three sub-populations. There were moderate to high levels of differentiation between P. griseola populations, with pairwise Fst values ranging from 0.11 to 0.95. The Andean population was composed of isolates from Tanzania, and was separated from the Middle American population (Fst = 0.95). The Middle American population was separated into 3 subpopulations including isolates from: 1. Guatemala and Honduras, 2. Tanzania, and 3. Puerto Rico. Pathogenicity testing of 27 isolates from Puerto Rico, using 12 common bean differential lines, identified ten races, but these races were not associated with SNPs found in virulence genes. DNA of an endophytic bacterium (Achromobacter xylosoxidans) was found in seven mildly virulent isolates suggesting a possible role of the bacterium in the observed virulence patterns. To understand the evolution and diversity of P. griseola, further study of the virulence genes and the interactions among the endophytic bacterium, the fungus, and the host plant is required. Such information is critical to inform breeding strategies for the development of resistant germplasm and cultivars.

Serrato-Diaz, Luz M. [U.S. Department of Agricultu↗

DOE OSTI2021

In situ characterization of laser-generated melt pools using synchronized ultrasound and high-speed X-ray imaging

Metal additive manufacturing is a fabrication method that forms a part by fusing layers of powder to one another. An energy source, such as a laser, is commonly used to heat the metal powder sufficiently to cause a molten pool to form, which is known as the melt pool. The melt pool can exist in the conduction or the keyhole mode where the material begins to rapidly evaporate. The interaction between the laser and the material is physically complex and difficult to predict or measure. Here, high-speed X-ray imaging was combined with immersion ultrasound to obtain synchronized measurements of stationary laser-generated melt pools. Furthermore, two-dimensional and three-dimensional finite-element simulations were conducted to help explain the ultrasonic response in the experiments. In particular, the time-of-flight and amplitude in pulse-echo configuration were observed to have a linear relationship to the depth of the melt pool. These results are promising for the use of ultrasound to characterize the melt pool behavior and for finite-element simulations to aid in interpretation.

42 ENGINEERING↗