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DOE OSTI2014

Long-Term Outcomes and Complications in Patients With Craniopharyngioma: The British Columbia Cancer Agency Experience

Purpose: We report long-term outcomes and complications of craniopharyngioma patients referred to our institution. Methods and Materials: Between 1971 and 2010, 123 consecutive patients received primary treatment for craniopharyngioma in British Columbia and were referred to our institution. The median age was 30 years (range, 2-80 years). Thirty-nine percent of patients were treated primarily with subtotal resection (STR) and radiation therapy (RT), 28% with STR alone, 15% with gross total resection, 11% with cyst drainage (CD) alone, 5% with CD+RT, and 2% with RT alone. Eight percent of patients received intracystic bleomycin (ICB) therapy. Results: Median follow-up was 8.9 years, and study endpoints were reported at 10 years. Ten-year Kaplan-Meier progression-free survival (PFS) was 46%. Patients treated with STR+RT or CD+RT had the highest PFS (82% and 83%, respectively). There were no significant differences between PFS after adjuvant versus salvage RT (84% vs 74%, respectively; P=.6). Disease-specific survival (DSS) was 88%, and overall survival (OS) was 80%. Primary treatment modality did not affect DSS or OS, while older age was a negative prognostic factor for OS but not DSS. Kaplan-Meier rates for visual deterioration, anterior pituitary hormone deficiency, diabetes insipidus, seizure disorder, and cerebrovascular events (CVE) due to treatment, not tumor progression, were 27%, 76%, 45%, 16%, and 11%, respectively. The CVE rate was 29% in patients who received ICB compared to 10% in those who did not (P=.07). Conclusions: We report favorable PFS in patients with craniopharyngioma, especially in those who received RT after surgery. DSS and OS rates were excellent regardless of primary treatment modality. We observed a high incidence of hypopituitarism, visual deterioration, and seizure disorder. Eleven percent of patients experienced CVEs after treatment. There was a suggestion of increased CVE risk in patients treated with ICB.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

DOE OSTI2021

Discovery of widespread transcription initiation at microsatellites predictable by sequence-based deep neural network

Using the Cap Analysis of Gene Expression (CAGE) technology, the FANTOM5 consortium provided one of the most comprehensive maps of transcription start sites (TSSs) in several species. Strikingly, ~72% of them could not be assigned to a specific gene and initiate at unconventional regions, outside promoters or enhancers. Here, we probe these unassigned TSSs and show that, in all species studied, a significant fraction of CAGE peaks initiate at microsatellites, also called short tandem repeats (STRs). To confirm this transcription, we develop Cap Trap RNA-seq, a technology which combines cap trapping and long read MinION sequencing. We train sequence-based deep learning models able to predict CAGE signal at STRs with high accuracy. These models unveil the importance of STR surrounding sequences not only to distinguish STR classes, but also to predict the level of transcription initiation. Importantly, genetic variants linked to human diseases are preferentially found at STRs with high transcription initiation level, supporting the biological and clinical relevance of transcription initiation at STRs. Together, our results extend the repertoire of non-coding transcription associated with DNA tandem repeats and complexify STR polymorphism.

59 BASIC BIOLOGICAL SCIENCES↗

DOE OSTI2017

Candidatus Mycoplasma girerdii replicates, diversifies, and co-occurs with Trichomonas vaginalis in the oral cavity of a premature infant

Genital mycoplasmas, which can be vertically transmitted, have been implicated in preterm birth, neonatal infections, and chronic lung disease of prematurity. Our prior work uncovered 16S rRNA genes belonging to a novel, as-yet-uncultivated mycoplasma (lineage 'Mnola') in the oral cavity of a premature neonate. Here, we characterize the organism's associated community, growth status, metabolic potential, and population diversity. Sequencing of genomic DNA from the infant's saliva yielded 1.44 Gbp of high-quality, non-human read data, from which we recovered three essentially complete (including 'Mnola') and three partial draft genomes (including Trichomonas vaginalis). The completed 629,409-bp 'Mnola' genome (Candidatus Mycoplasma girerdii str. UC-B3) was distinct at the strain level from its closest relative, vaginally-derived Ca. M. girerdii str. VCU-M1, which is also associated with T. vaginalis. Replication rate measurements indicated growth of str. UC-B3 within the infant. Genes encoding surface-associated proteins and restriction-modification systems were especially diverse within and between strains. In UC-B3, the population genetic underpinnings of phase variable expression were evident in vivo. Unique among mycoplasmas, Ca. M. girerdii encodes pyruvate-ferredoxin oxidoreductase and may be sensitive to metronidazole. This study reveals a metabolically unique mycoplasma colonizing a premature neonate, and establishes the value of genome-resolved metagenomics in tracking phase variation.

60 APPLIED LIFE SCIENCES↗

DOE OSTI2022

Epidermal growth factor receptor cascade prioritizes the maximization of signal transduction

Many studies have been performed to quantify cell signaling. Cell signaling molecules are phosphorylated in response to extracellular stimuli, with the phosphorylation sequence forming a signal cascade. The information gain during a signal event is given by the logarithm of the phosphorylation molecule ratio. The average information gain can be regarded as the signal transduction quantity (ST), which is identical to the Kullback–Leibler divergence (KLD), a relative entropy. We previously reported that if the total ST value in a given signal cascade is maximized, the ST rate (STR) of each signaling molecule per signal duration (min) approaches a constant value. To experimentally verify this theoretical conclusion, we measured the STR of the epidermal growth factor (EGF)-related cascade in A431 skin cancer cells following stimulation with EGF using antibody microarrays against phosphorylated signal molecules. The results were consistent with those from the theoretical analysis. Thus, signaling transduction systems may adopt a strategy that prioritizes the maximization of ST. Furthermore, signal molecules with similar STRs may form a signal cascade. In conclusion, ST and STR are promising properties for quantitative analysis of signal transduction.

59 BASIC BIOLOGICAL SCIENCES↗

DOE OSTI2016

SU-D-BRA-07: Applications of Combined KV/MV CBCT Imaging with a High-DQE MV Detector

Purpose: To investigate whether a high detection quantum efficiency (DQE) MV detector makes combined kV/MV CBCT clinically practical. Methods: Combined kV/MV CBCT was studied for scan time reduction (STR) and metal artifact reduction (MAR). 6MV CBCT data (dose rate = 0.017 MU/degree) were collected using 1) a novel focused pixelated cadmium tungstate (CWO) scintillator (15mm thickness, DQE(0) = 22%, 0.784mm pixel pitch) coupled to a flat panel imager, and 2) a commercial portal imager with a 133mg/cm{sup 2} gadolinium oxysulfide (GOS) screen (DQE(0) = 1.2%). The 100kVp data were acquired using a commercial imager employing a columnar cesium iodide scintillator (DQE(0) = 70%) with a dose rate of 0.0016 cGy/degree. For STR, MV and kV projections spanning 105° were combined to constitute a complete CBCT scan. Total dose was ∼2cGy and acquisition time was 18s. For MAR, only the metalcorrupted pixels in the kV projections were replaced with MV data resulting in a total dose of less than 1cGy for a 360° scan. Image quality was assessed using an 18-cm diameter electron density phantom with nine tissue inserts, some of which were replaced with steel rods for MAR studies. Results: The CWO contrast-to-noise ratio (CNR) was ∼4.0x higher than the GOS CNR and was ∼4.8x lower than the kV CNR when normalized for dose. When CWO MV data were combined with kV data for STR, all contrast inserts were visible, but only two were detectable in the composite kV/GOS image. Metal artifacts were greatly reduced using the kV/MV MAR technique with all contrast inserts clearly visible in the composite kV/CWO image but only two inserts visible in the composite kV/GOS image. Conclusion: We have demonstrated that a high DQE MV detector significantly improves kV/MV CBCT image quality thus enabling scan time reduction and metal artifact reduction without a severe dose penalty. AW and JS-L are employees of Varian, RF is an employee of Siemens.

60 APPLIED LIFE SCIENCES↗

DOE OSTI2018

Genus-wide assessment of lignocellulose utilization in the extremely thermophilic Caldicellulosiruptor by genomic, pan-genomic and metagenomic analysis

Metagenomic data from Obsidian Pool (Yellowstone National Park, USA) and thirteen genome sequences were used to re-assess genus-wide biodiversity for the extremely thermophilic Caldicellulosiruptor . The updated core-genome contains 1,401 ortholog groups (average genome size for thirteen species = 2,516 genes). The pan-genome, which remains open with a revised total of 3,493 ortholog groups, encodes a variety of multi-domain glycoside hydrolases (GH). These include three cellulases with GH48 domains that are co-located in the Glucan Degradation Locus (GDL) and are specific determinants for microcrystalline cellulose utilization. Three recently sequenced species, Caldicellulosiruptor sp. str. Rt8.B8 (re-named here Caldicellulosiruptor morganii ), Thermoanaerobacter cellulolyticus str. NA10 (re-named here Caldicellulosiruptor naganoensis NA10), and Caldicellulosiruptor sp. str. Wai35.B1 (re-named here Caldicellulosiruptor danielii ) degraded Avicel and lignocellulose (switchgrass). C. morganii was more efficient than C. bescii in this regard and differed from the other twelve species examined here, both based on genome content and organization and in the specific domain features of conserved GHs. Metagenomic analysis of lignocellulose-enriched samples from Obsidian Pool revealed limited new information on genus biodiversity. Enrichments yielded genomic signatures closely related to Caldicellulosiruptor obsidiansis , but there was also evidence for other thermophilic fermentative anaerobes ( Caldanaerobacter , Fervidobacterium , Caloramator , and Clostridium ). One enrichment, containing 89.7% Caldicellulosiruptor and 9.7% Caloramator , had a capacity for switchgrass solubilization comparable to C. bescii . These results refine the known biodiversity of Caldicellulosiruptor and indicate that microcrystalline cellulose degradation at temperatures above 70°C, based on current information, is limited to certain members of this genus that produce GH48 domain-containing enzymes. The genus Caldicellulosiruptor contains the most thermophilic bacteria capable of lignocellulose deconstruction and are promising candidates for consolidated bioprocessing for the production of biofuels and bio-based chemicals. The focus here is on the extant capability of this genus for plant biomass degradation and the extent to which this can be inferred from the core and pan-genomes, based on analysis of thirteen species and metagenomic sequence information from environmental samples. Key to microcrystalline hydrolysis is the content of the Glucan Degradation Locus (GDL), a set of genes encoding glycoside hydrolases (GH), several of which have GH48 and family 3 carbohydrate binding module domains, that function as primary cellulases. Resolving the relationship between the GDL and lignocellulose degradation will inform efforts to identify more prolific members of the genus and to develop metabolic engineering strategies to improve this characteristic

59 BASIC BIOLOGICAL SCIENCES↗

NASA NTRS1985

Solar thermal propulsion for planetary spacecraft

Previous studies have shown that many desirable planetary exploration missions require large injection delta-V. Solar Thermal Rocket (STR) propulsion, under study for orbit-raising applications may enhance or enable such high-energy missions. The required technology of thermal control for liquid hydrogen propellant is available for the required storage duration. Self-deploying, inflatable solar concentrators are under study. The mass penalty for passive cryogenic thermal control, liquid hydrogen tanks and solar concentrators does not compromise the specific impulse advantage afforded by the STR as compared to chemical propulsion systems. An STR injection module is characterized and performance is evaluated by comparison to electric propulsion options for the Saturn Orbiter Titan Probe (SOTP) and Uranus Flyby Uranus Probe (UFUP) missions.

Sercel, J. C.↗

NASA NTRS1992

A global monthly sea surface temperature climatology

The paper presents a new global 2 deg x 2 deg monthly sea surface temperature (SST) climatology, referred here to as the Shea-Trenberth-Reynolds (STR) climatology, which was derived by modifying a 1950-1979-based SST climatology from the Climate Analysis Center (CAC), by using data from the Comprehensive Ocean-Atmosphere Data Set to improve the SST estimates in the regions of the Kuroshio and the Gulf Stream. A comparison of the STR climatology with the Alexander and Mobley SST climatology showed that the STR climatology is warmer in the Northern Hemisphere, and colder poleward of 45 deg S.

Shea, Dennis J.↗

NASA NTRS2002

Development of inflatable antenna structures

Self-rigidizable spring-tape-reinforced (STR) booms were used to develop structural systems for large-aperture space inflatable radar antennas. The lightweight planar frames built with STR booms can be compactly stowed for launch, deployed by inflation pressure in space, and used to tension the RF membrane apertures of the antennas. Engineering models of a Ka-band reflectarray antenna and a L-band synthetic-aperture radar antenna were developed and have successfully demonstrated stowage and deployment, as well as RF performance. A design improvement was also being implemented to enhance long-term configuration stability and widen the application range of the STR booms.

inflatable antenna structures deployment↗

NASA NTRS2006

An eight-meter inflatable reflectarray antenna and its inflatable/self-rigidizable booms

This paper presents the analysis and test results related to buckling capability, modal characteristics, and thermal expansion coefficient of STR aluminum laminate inflatable/self-rigidizable booms with lengths up to 10 metes. STR booms are fundamental building blocks of space inflatable/self-rigidizable reflectarray antennas. These boom characteristics are essential for analyzing structural integrity, in orbit dynamic response, and in orbit thermal distortion of the 8-mter reflectarray antenna. Distinct advantages of the STR booms will also be identified and presented by this paper.

membranes↗

NASA NTRS2007

Operational Experience with Autonomous Star Trackers on ESA Interplanetary Spacecraft

Mars Express (MEX), Rosetta and Venus Express (VEX) are ESA interplanetary spacecrafts (S/C) launched in June 2003, March 2004 and November 2005, respectively. Mars Express was injected into Mars orbit end of 2003 with routine operations starting in spring 2004. Rosetta is since launch on its way to rendezvous comet Churyumov-Gerasimenko in 2014. It has completed several test and commissioning activities and is performing several planetary swingbys (Earth in spring 2005, Mars in spring 2007, Earth in autumn 2007 and again two years later). Venus Express has also started routine operations since the completion of the Venus orbit insertion maneuver sequence beginning of May 2006. All three S/C are three axes stabilized with a similar attitude and orbit control system (AOCS). The attitude is estimated on board using star and rate sensors and controlled using four reaction wheels. A bipropellant reaction control system with 10N thrusters serves for wheel off loadings and attitude control in safe mode. Mars Express and Venus Express have an additional 400N engine for the planetary orbit insertion. Nominal Earth communication is accomplished through a high gain antenna. All three S/C are equipped with a redundant set of autonomous star trackers (STR) which are based on almost the same hardware. The STR software is especially adapted for the respective mission. This paper addresses several topics related to the experience gained with the STR operations on board the three S/C so far.

Lauer, Mathias↗

NASA NTRS2010

TPSAS-NF1676L-10980-DND

We plan to perform the following sets of computations on unadapted (fixed) grids: 1) Structured RANS set 1 (Code: CFL3D, Grid: Str-OnetoOne-A-v1 (supplied by HiLiftPW-1 committee), Turbulence model: Spalart-Allmaras), 2) Structured RANS set 2 (Code: CFL3D, Grid: Str-OnetoOne-A-v1 (supplied by HiLiftPW-1 committee), Turbulence model: Menter SST), 3) Structured RANS set 3 (time permitting) (Code: CFL3D, Grid: Str-OnetoOne-B-v1 (supplied by HiLiftPW-1 committee), Turbulence model: Menter SST), 4) Unstructured RANS set 1 (Code: FUN3D, Grid: Unst-Mixed-FromTet-Nodecentered-A-v1 (supplied by HiLiftPW-1 committee), Turbulence model: Spalart-Allmaras), and 5) Unstructured RANS set 2 (time permitting) (Code: FUN3D, Grid: Unst-Hex-FromOnetoOne-A-v1 (supplied by HiLiftPW-1 committee), Turbulence model: Spalart-Allmaras),. Optional case 3 is not being computed. CFL3D is a structured upwind-biased cell-centered RANS code,1 and FUN3D is an unstructured upwind-biased node-centered RANS code

Elizabeth M Lee-Rausch↗

NASA NTRS2010

TPSAS-NF1676L-10454-DND

C L Rumsey↗

DOE OSTI2014

Assessment of Chronological Effects of Irreversible Electroporation on Hilar Bile Ducts in a Porcine Model

Purpose: To evaluate the chronological effects of irreversible electroporation (IRE) on large hilar bile ducts in an in vivo porcine model correlated with computed tomography (CT) cholangiography and histopathology. Materials and Methods: Twelve IRE zones were made along hilar bile ducts intraoperatively under ultrasound (US)-guidance in 11 pigs. Paired electrodes were placed either on opposing sides of the bile duct (straddle [STR]) or both on one side of the bile duct (one-sided [OSD]). The shortest electrode-to-duct distance was classified as periductal (≤2 mm) or nonperiductal (>2 mm). CT cholangiography and laboratory tests were performed before IRE and again at 2 days, 4 weeks, and 8 weeks after IRE. Degree of bile duct injury were graded as follows: grade 0 = no narrowing; grade 1 = ≤50 % duct narrowing; grade 2 = >50 % narrowing without proximal duct dilatation; grade 3 = grade 2 with proximal duct dilatation; and grade 4 = grade 3 with enzyme elevation. Pigs were selected for killing and histopathology at 2 days, 4, and 8 weeks. Results: Nonperiductal electrode placement produced no long-term strictures in 5 of 5 ducts. Periductal electrode placement produced mild narrowing in 6 of 7 ducts: 5 grade 1 and 1 grade 2. None showed increased enzymes. There was no significant difference between STR versus OSD electrode placement. Histopathology showed minor but relatively greater ductal mural changes in narrowed ducts. Conclusion: In the larger hilar ducts, long-term patency and mural integrity appear resistant to IRE damage with the energy deposition used, especially if the electrode is not immediately periductal in position.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

DOE OSTI2025

Exascale granular microstructure reconstruction in 3D volumes of arbitrary geometries with generative learning

Reconstructing 3D granular microstructures within volumes of arbitrary geometries from limited 2D image data is crucial for predicting the material properties, as well as performances of structural components accounting for material microstructural effects. We present a novel generative learning framework that enables exascale reconstruction of granular microstructures within complex 3D geometric volumes. Building upon existing transfer learning techniques using pre-trained convolutional neural networks (CNN), we introduce several key innovations to overcome the difficulties inherent in arbitrary geometries. Our framework incorporates periodic boundary conditions using circular padding techniques, ensuring continuity and representativeness of the reconstructed microstructures. We also introduce a novel seamless transition reconstruction (STR) method that creates statistically equivalent transition zones to integrate multiple pre-existing 3D microstructure volumes. Based on STR, we propose a cost-effective strategy for reconstructing microstructures within complex geometric volumes, minimizing computational waste. Validation through numerical experiments using kinetic Monte Carlo simulations demonstrates accurate reproduction of grain statistics, including grain size distributions and morphology. A case study involving the reconstruction of a 4-blade propeller microstructure illustrates the method’s capability to efficiently handle complex geometries. In conclusion, the proposed framework significantly reduces computational demands while maintaining high reconstruction quality, paving the way for scalable microstructure reconstruction in materials design and analysis.

36 MATERIALS SCIENCE↗

DOE OSTI2013

Management of Pediatric Myxopapillary Ependymoma: The Role of Adjuvant Radiation

Introduction: Myxopapillary ependymoma (MPE) is a rare tumor in children. The primary treatment is gross total resection (GTR), with no clearly defined role for adjuvant radiation therapy (RT). Published reports, however, suggest that children with MPE present with a more aggressive disease course. The goal of this study was to assess the role of adjuvant RT in pediatric patients with MPE. Methods: Sixteen patients with MPE seen at Johns Hopkins Hospital (JHH) between November 1984 and December 2010 were retrospectively reviewed. Fifteen of the patients were evaluable with a mean age of 16.8 years (range, 12-21 years). Kaplan-Meier curves and descriptive statistics were used for analysis. Results: All patients received surgery as the initial treatment modality. Surgery consisted of either a GTR or a subtotal resection (STR). The median dose of adjuvant RT was 50.4 Gy (range, 45-54 Gy). All patients receiving RT were treated at the involved site. After a median follow-up of 7.2 years (range, 0.75-26.4 years), all patients were alive with stable disease. Local control at 5 and 10 years was 62.5% and 30%, respectively, for surgery alone versus 100% at both time points for surgery and adjuvant RT. Fifty percent of the patients receiving surgery alone had local failure. All patients receiving STR alone had local failure compared to 33% of patients receiving GTR alone. One patient in the surgery and adjuvant RT group developed a distant site of recurrence 1 year from diagnosis. No late toxicity was reported at last follow-up, and neurologic symptoms either improved or remained stable following surgery with or without RT. Conclusions: Adjuvant RT improved local control compared to surgery alone and should be considered after surgical resection in pediatric patients with MPE.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

DOE OSTI2014

The contribution of heavy metals in cigarette smoke condensate to malignant transformation of breast epithelial cells and in vivo initiation of neoplasia through induction of a PI3K–AKT–NFκB cascade

Cigarette smoking is a crucial factor in the development and progression of multiple cancers including breast. Here, we report that repeated exposure to a fixed, low dose of cigarette smoke condensate (CSC) prepared from Indian cigarettes is capable of transforming normal breast epithelial cells, MCF-10A, and delineate the biochemical basis for cellular transformation. CSC transformed cells (MCF-10A-Tr) were capable of anchorage-independent growth, and their anchorage dependent growth and colony forming ability were higher compared to the non-transformed MCF-10A cells. Increased expression of biomarkers representative of oncogenic transformation (NRP-1, Nectin-4), and anti-apoptotic markers (PI3K, AKT, NFκB) were also noted in the MCF-10A-Tr cells. Short tandem repeat (STR) profiling of MCF-10A and MCF-10A-Tr cells revealed that transformed cells acquired allelic variation during transformation, and had become genetically distinct. MCF-10A-Tr cells formed solid tumors when implanted into the mammary fat pads of Balb/c mice. Data revealed that CSC contained approximately 1.011 μg Cd per cigarette equivalent, and Cd (0.0003 μg Cd/1 × 10{sup 7} cells) was also detected in the lysates from MCF-10A cells treated with 25 μg/mL CSC. In similar manner to CSC, CdCl{sub 2} treatment in MCF-10A cells caused anchorage independent colony growth, higher expression of oncogenic proteins and increased PI3K–AKT–NFκB protein expression. An increase in the expression of PI3K–AKT–NFκB was also noted in the mice xenografts. Interestingly, it was noted that CSC and CdCl{sub 2} treatment in MCF-10A cells increased ROS. Collectively, results suggest that heavy metals present in cigarettes of Indian origin may substantially contribute to tumorigenesis by inducing intercellular ROS accumulation and increased expression of PI3K, AKT and NFκB proteins. - Highlights: • Repeated exposure of CSC causes malignant transformation in MCF-10A. • MCF-10A-Tr cells showed a distinct STR profile and tumor inducing characteristics. • Increased expression of PI3K, AKT, and NFκB protein in MCF-10A-Tr and solid tumor. • Increased ROS and PI3K-AKT-NFκB proteins in smoke carcinogen exposed MCF-10A cells. • Cadmium may be a strong contributor to the transformation of MCF-10A cells.

60 APPLIED LIFE SCIENCES↗

DOE OSTI2026

Contrasting effects of glutamate and branched-chain amino acid metabolism on acid tolerance in a Castellaniella isolate from acidic groundwater

Groundwater acidification co-occurring with nitrate pollution is a common, global environmental health hazard. Denitrifying bacteria have been leveraged for the in situ removal of nitrate in groundwater. However, co-existing stressors—such as low pH—reduce the efficacy of biological removal processes. Castellaniella sp. str. MT123 is a complete denitrifier that was isolated from acidic, nitrate-contaminated groundwater. The strain grows robustly by nitrate respiration at pH < 6.0, completely reducing nitrate to dinitrogen gas. Genomic analyses of MT123 revealed few previously characterized acid tolerance genes. Thus, we utilized a combination of proteomics, metabolomics, and competitive mutant fitness to characterize the genetic mechanisms of MT123 acclimation to growth under mildly acidic conditions. We found that glutamate accumulation is critical in the acid acclimation of MT123, possibly through consumption of intracellular protons via glutamate decarboxylation to GABA. This is despite the fact that MT123 lacks the canonical glutamate decarboxylase-glutamate/GABA antiporter system implicated in acid tolerance in other bacteria. In contrast, branched-chain amino acid (BCAA) accumulation was detrimental to cell growth at lower pHs, possibly through indirect mechanisms impacting the cellular glutamate pool. Genetic analysis previously linked MT123 to a population of Castellaniella that bloomed—concurrent to nitrate removal—during a biostimulation effort to reduce groundwater nitrate concentrations at MT123’s location of origin. Thus, our analyses provide novel insight into mechanisms of acclimation to acidic conditions in a strain with significant potential for nitrate bioremediation.

59 BASIC BIOLOGICAL SCIENCES↗