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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 OSTI2018

TL/OSL properties of beta irradiated Al2O3:Tm3+ phosphor synthesized by microwave combustion method

Highlights: • TL emission spectra of γ – rayed Al{sub 2}O{sub 3}:Tm{sup 3+} shows Tm{sup 3+} characteristic transitions. • Doping of Tm{sup 3+} ions causes enhancement of TL/OSL. • TL/OSL kinetic parameters are analyzed by CGCD method. • TL mechanism of γ/β – rayed Al{sub 2}O{sub 3}:Tm{sup 3+} was proposed. • TL/OSL dosimetric properties of Al{sub 2}O{sub 3}:Tm{sup 3+} suggests that the material is appropriate for medical dosimetry. - Abstract: This work discusses synthesis of stable α-phase of Al{sub 2}O{sub 3}:Tm{sup 3+} by combustion method using temperature controlled microwave oven. The crystalline phase was analyzed by X-ray diffraction (XRD) technique and average crystallite size was found to be 147 nm. Observations using scanning electron microscope (SEM) image suggest formation of agglomerated particles and energy dispersive x-ray spectroscopy (EDS) confirmed the incorporation of Tm{sup 3+} in Al{sub 2}O{sub 3}. Thermoluminescence emission (TLE) spectrum of γ – irradiated Al{sub 2}O{sub 3}:Tm{sup 3+} shows characteristic emissions of Tm{sup 3+}, Cr{sup 3+} and Mn{sup 4+}. TL glow curves of γ – irradiated Al{sub 2}O{sub 3}:Tm{sup 3+} exhibit a prominent peak at 453 K along with a shoulder at 496 K. The glow curves of β – irradiated Al{sub 2}O{sub 3}:Tm{sup 3+} were studied in different emission regions using U340 + BG39 (UV band pass), CS759 + BG39 (Blue band pass) and BG39 (Visible band pass) optical glass filters. A prominent peak was observed at 471 K in for all mentioned emission regions and an additional shoulder was observed at 511 K with CS759 + BG39 and BG39 filters. TL glow curve of β – irradiated Al{sub 2}O{sub 3}:Tm{sup 3+} using only BG39 filter had more counts than CS759 + BG39 and U340 + BG39 filters. Further, the effect of Tm{sup 3+} impurity on TL response was studied. TL kinetic parameters were estimated by using computerized glow curve deconvolution (CGCD) technique. The activation energy and frequency factor of prominent peak (471 K) were found to be 1.31 eV and 3.50 × 10{sup 13} s{sup −1} respectively. Optically stimulated luminescence (OSL) characteristics of β – irradiated Al{sub 2}O{sub 3}:Tm{sup 3+} were studied using U340 + BG39 and CS759 + BG39 filters. Highest OSL intensity was observed in UV. OSL curves were deconvoluted by general order decay equation. Life time and photoionization cross section of the traps responsible for OSL were found to be 5.30 s and 3.98 × 10{sup −18} cm{sup 2} respectively. The process of ionization of electron from Tm{sup 3+}, electron trap in host lattice and its recombination mechanism is proposed. Phosphorescence decay of beta irradiated sample was also studied. The lifetime of phosphorescence decay was found to be 140 s for the prominent peak and TL intensity decays 25% after the phosphorescence. TL/OSL dosimetric properties viz. linearity with dose, reusability and minimum detectable dose of the phosphor were characterized for medical dosimetry application.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2012

Updated Results and Patterns of Failure in a Randomized Hypofractionation Trial for High-risk Prostate Cancer

Purpose: To report long-term results and patterns of failure after conventional and hypofractionated radiation therapy in high-risk prostate cancer. Methods and Materials: This randomized phase III trial compared conventional fractionation (80 Gy at 2 Gy per fraction in 8 weeks) vs hypofractionation (62 Gy at 3.1 Gy per fraction in 5 weeks) in combination with 9-month androgen deprivation therapy in 168 patients with high-risk prostate cancer. Freedom from biochemical failure (FFBF), freedom from local failure (FFLF), and freedom from distant failure (FFDF) were analyzed. Results: In a median follow-up of 70 months, biochemical failure (BF) occurred in 35 of the 168 patients (21%) in the study. Among these 35 patients, local failure (LF) only was detected in 11 (31%), distant failure (DF) only in 16 (46%), and both LF and DF in 6 (17%). In 2 patients (6%) BF has not yet been clinically detected. The risk reduction by hypofractionation was significant in BF (10.3%) but not in LF and DF. We found that hypofractionation, with respect to conventional fractionation, determined only an insignificant increase in the actuarial FFBF but no difference in FFLF and FFDF, when considering the entire group of patients. However, an increase in the 5-year rates in all 3 endpoints-FFBF, FFLF, and FFDF-was observed in the subgroup of patients with a pretreatment prostate-specific antigen (iPSA) level of 20 ng/mL or less. On multivariate analysis, the type of fractionation, iPSA level, Gleason score of 4+3 or higher, and T stage of 2c or higher have been confirmed as independent prognostic factors for BF. High iPSA levels and Gleason score of 4+3 or higher were also significantly associated with an increased risk of DF, whereas T stage of 2c or higher was the only independent variable for LF. Conclusion: Our results confirm the isoeffectiveness of the 2 fractionation schedules used in this study, although a benefit in favor of hypofractionation cannot be excluded in the subgroup of patients with an iPSA level of 20 ng/mL or less. The {alpha}/{beta} ratio might be more appropriately evaluated by FFLF than FFBF results, at least in high-risk disease.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2013

A PARAMETER STUDY FOR BAROCLINIC VORTEX AMPLIFICATION

Recent studies have shown that baroclinic vortex amplification is strongly dependent on certain factors, namely, the global entropy gradient, the efficiency of thermal diffusion and/or relaxation as well as numerical resolution. We conduct a comprehensive study of a broad range and combination of various entropy gradients, thermal diffusion and thermal relaxation timescales via local shearing sheet simulations covering the parameter space relevant for protoplanetary disks. We measure the Reynolds stresses as a function of our control parameters and see that there is angular momentum transport even for entropy gradients as low as {beta} = -dln s/dln r = 1/2. Values we expect in protoplanetary disks are between {beta} = 0.5-2.0 The amplification-rate of the perturbations, {Gamma}, appears to be proportional to {beta}{sup 2} and thus proportional to the square of the Brunt-Vaeisaelae frequency ({Gamma}{proportional_to}{beta}{sup 2}{proportional_to}N {sup 2}). The saturation level of Reynolds stresses, on the other hand, seems to be proportional to {beta}{sup 1/2}. This highlights the importance of baroclinic effects even for the low entropy gradients expected in protoplanetary disks.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2016

Functional roles of CymA and NapC in reduction of nitrate and nitrite by Shewanella putrefaciens W3-18-1

Shewanella putrefaciens W3-18-1 harbours two periplasmic nitrate reductase (Nap) gene clusters, NapC-associated nap-alpha (napEDABC) and CymA-dependent nap-beta (napDAGHB), for dissimilatory nitrate respiration. CymA is a member of the NapC/NirT quinol dehydrogenase family and acts as a hub to support different respiratory pathways, including those on iron [Fe(III)] and manganese [Mn(III, IV)] (hydr)oxide, nitrate, nitrite, fumarate and arsenate in Shewanella strains. However, in our analysis it was shown that another NapC/NirT family protein, NapC, was only involved in nitrate reduction, although both CymA and NapC can transfer quinol-derived electrons to a periplasmic terminal reductase or an electron acceptor. Furthermore, our results showed that NapC could only interact specifically with the Nap-alpha nitrate reductase while CymA could interact promiscuously with Nap-alpha, Nap-beta and the NrfA nitrite reductase for nitrate and nitrite reduction. To further explore the difference in specificity, site-directed mutagenesis on both CymA and NapC was conducted and the phenotypic changes in nitrate and nitrite reduction were tested. Our analyses demonstrated that the Lys-91 residue played a key role in nitrate reduction for quinol oxidation and the Asp-166 residue might influence the maturation of CymA. The Asp-97 residue might be one of the key factors that influence the interaction of CymA with the cytochromes NapB and NrfA.

59 BASIC BIOLOGICAL SCIENCES↗
NASA NTRS1993

Wind variability in the Large Magellanic Cloud B(e) supergiant HD 34664

We present optical linear spectropolarimetry of the B(e) supergiant HD 34664. The polarization and position angle display significant spectral features which correspond to the H-alpha and H-beta emission lines. We use the line polarizations to separate the interstellar foreground polarization from the intrinsic polarization of HD 34664. The intrinsic polarization is consistent with electron scattering in a circumstellar disk seen at high inclination and provides further and independent evidence for the two-component wind model of the B(e) supergiants. We compare the polarization and spectrum of HD 34664 to observations published in the literature. In our data the continuum polarization is by a factor of two larger and the H-alpha line-to-continuum ratio is by a factor of at least four increased over previous observations. Since both the polarization and the line intensity are measures of the electron density in the stellar wind, we suggest that the observed variations can be attributed to a rise in the stellar mass-loss rate.

Schulte-Ladbeck, R. E.↗
NASA NTRS2017

Vascular Patterning Analysis by VESGEN 2D/3D with Bioinformatics: Updates for Rodent Tissues

Fractally branching vascular systems are a complex physiological requirement shared by humans with all higher terrestrial life forms, including other vertebrates, insects, and higher land plants. Vascular trees, networks, and tree-network composites are therefore mapped and quantified by the VESsel GENeration Analysis (VESGEN) software according to weighted physiological vascular rules that include vessel connectivity, tapering and bifurcational branching. According to fluid dynamics, successful vascular transport depends upon a complex distributed system of highly regulated laminar flow. VESGEN has elucidated changes in vascular patterning resulting from inflammatory, developmental and other signaling pathways within numerous tissues of major model organisms important for Space Biology, especially for rodents. Important early stage regenerative opportunities have been identified by VESGEN vascular analysis for visual impairments in the human retina, and is currently being used for research into astronaut visual and ocular disorders associated with long duration missions. The VESGEN 2D software is a mature, automated, widely published capability for which beta testing and public release by NASA is planned for the upcoming year. Early-stage capabilities for VESGEN 3D analysis are under development for the rodent retina and intestine as prototype tissues. A prototype VESGEN 2D Bioinformatics software capability has also been developed to associate phenotypic changes in molecular expression with vascular structure and function. By new VESGEN bioinformatic innovations, expression patterns of the genetic, transcriptional, protein and other markers for regulatory molecules such as vascular endothelial growth factor (VEGF) and their receptors, often indicators of tissue oxygenation status, are co-localized with alterations in vascular pattern. Biomarkers are therefore mapped and quantified as information dimensions directly correlated with the spatial dimensions of a vascular pattern. Further important technology innovations by NASA include substantial image segmentation advances for more automated binary extraction of the grayscale vascular patterns, together with informative associated image quality assessments. Vascular mapping and quantification capabilities for the rodent retina and intestine are illustrated for VESGEN 2D, along with technology status reports on VESGEN 3D and Bioinformatic capabilities. Research partially supported by Ames Center Innovation Awards.

Parsons-Wingerter, P.↗
DOE OSTI2017

Chemical/Optical Properties of Oliktok Aerosols Field Campaign Report

The arctic environment is changing at an alarming rate. During this time of escalation, it is important to understand the impacts of aerosols, both natural and anthropogenic. To support this effort, an aerosol sampling campaign was conducted at the U.S. Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) Climate Research Facility third Mobile Facility (AMF3) at Oliktok Point on the North Slope of Alaska (NSA). The specific objectives of the campaign were to collect aerosol particles as a function of aerodynamic particle size in order to better understand the varying chemical and optical properties of the aerosols in the different particle size modes. A DRUM-style cascading impactor (Davis Rotating-Unit for Monitoring) was deployed at the beginning of March 2017 through the end of May 2017, collecting samples in eight size bins for each 12-hour period, thereby obtaining a diurnal signature. On March 6, a fire burned down the power generation shed at the sampling site. No samples were collected again until March 10. Due to DRUM sampler rotation issues, samples were collected intermittently until March 13. From March 14 through the end of the study, samples were collected with little interference. The size bins of the instrument range from approximately 10 to 0.09 μm; however, deployment at the Oliktok Point facility required an inlet configuration that effectively filtered out the coarsest size bin. Therefore, the reported size bins are 5.0 to 2.5, 2.5 to 1.15, 1.15 to 0.75, 0.75 to 0.56, 0.56 to 0.34, 0.34 to 0.26, and 0.26 to 0.09 μm. It is also possible that ultrafine particles were removed by electrostatic charging of the high-density polyethylene inlet tubing; however, confirmation of this would require further testing. The collected samples were returned to the University of California (UC), Davis for offline analysis. Particle mass concentrations were measured by soft-beta ray attenuation while optical attenuation was determined by broadband transmission spectrometry (10 wavelengths from 349 to 849 nm in 50 nm increments, minus 649 nm). The samples were then taken to the Advanced Light Source facility at Lawrence Berkeley National Laboratory for synchrotron-induced X-ray fluorescence spectrometry (SXRF). Thirty elements were detected, from sodium to molybdenum plus lead. The polarized nature of the synchrotron beam eliminates 97.5% of the primary Compton background, providing approximately a factor of 10 greater sensitivity than unpolarized X-ray instruments (Barberie et al. 2013). The data were reduced using custom software packages and analyzed for any sources of contamination, sample damage, or other potential causes of data invalidation. The interpretation of the final data set is ongoing and only early results will be described in this report. In spite of power and instrumental issues at the start, the field campaign was largely successful. Excluding the first stage that did not receive sample and power/rotational issues, the remaining stages were 99.7% complete (number of valid measurements/total number of measurements made). The percent of measurements below detection were < 30% for all species with the exception of sodium, magnesium, arsenic, and scandium. Sodium and magnesium were expected to be difficult to measure using SXRF due to low sensitivity at that energy range. Scandium is very rare in ambient samples unless near a very strong source. Arsenic is fairly common in urban settings but is not expected in the arctic environment.

54 ENVIRONMENTAL SCIENCES↗
NASA NTRS1975

Radiation effects on beta /10.6/ of pure and europium doped KCl

Changes in the optical absorption coefficient as the result of X-ray and electron bombardment of pure monocrystalline and polycrystalline KCl and of divalent europium doped polycrystalline KCl were determined. A constant heat flow calorimetric method was used to measure the optical absorption coefficients. Both 300 kV X-ray irradiation and 2 MeV electron irradiation produced increases in the optical absorption coefficient at room temperature. X-ray irradiation produced more significant changes in pure monocrystalline KCl than equivalent amounts of electron irradiation. Electron irradiation of pure and Eu-doped polycrystalline KCl produced increases in the absorption by as much as a factor of 20 over untreated material. Bleaching of the electron-irradiated doped KCl with 649 millimicron light produced a further increase.

Grimes, H. H.↗
DOE OSTI2021

GeantV: Results from the Prototype of Concurrent Vector Particle Transport Simulation in HEP

Full detector simulation was among the largest CPU consumers in all CERN experiment software stacks for the first two runs of the Large Hadron Collider. In the early 2010s, it was projected that simulation demands would scale linearly with increasing luminosity, with only partial compensation from increasing computing resources. The extension of fast simulation approaches to cover more use cases that represent a larger fraction of the simulation budget is only part of the solution, because of intrinsic precision limitations. The remainder corresponds to speeding up the simulation software by several factors, which is not achievable by just applying simple optimizations to the current code base. In this context, the GeantV R&D project was launched, aiming to redesign the legacy particle transport code in order to benefit from features of fine-grained parallelism, including vectorization and increased locality of both instruction and data. This paper provides an extensive presentation of the results and achievements of this R&D project, as well as the conclusions and lessons learned from the beta version prototype.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
NASA NTRS1990

On the disappearance of O I in some high-luminosity cool stars

Far UV spectra and flux measurements of cool giant and supergiant stars, focusing on the O I (UV 2) and S I/Si II fluxes and their dependence on stellar parameters are presented. The de-reddened O I surface fluxes vary by factors of several hundred over the 11 stars in the sample and, at a given luminosity, decrease with decreasing effective temperature. No flux at all is detected in the three M supergiants observed to date. In contrast, the S I/Si II blend near 1810 angstrom is clearly detected in all the stars. Its strength generally increases with luminosity, but has little effective temperature dependence. Possible explanations for the behavior of O I include changes in the intensities of Lyman alpha and beta which excite the lines of S I and O I, respectively, as well as scattering and/or absorption of the O I flux in a dense, circumstellar gas shell.

Carpenter, K. G.↗
NASA NTRS2009

Rapid Monitoring of Bacteria and Fungi aboard the International Space Station (ISS)

Microorganisms within spacecraft have traditionally been monitored with culture-based techniques. These techniques involve growth of environmental samples (cabin water, air or surfaces) on agar-type media for several days, followed by visualization of resulting colonies or return of samples to Earth for ground-based analysis. Data obtained over the past 4 decades have enhanced our understanding of the microbial ecology within space stations. However, the approach has been limited by the following factors: i) Many microorganisms (estimated > 95%) in the environment cannot grow on conventional growth media; ii) Significant time lags (3-5 days for incubation and up to several months to return samples to ground); iii) Condensation in contact slides hinders colony counting by crew; and iv) Growth of potentially harmful microorganisms, which must then be disposed of safely. This report describes the operation of a new culture-independent technique onboard the ISS for rapid analysis (within minutes) of endotoxin and beta-1, 3-glucan, found in the cell walls of gramnegative bacteria and fungi, respectively. The technique involves analysis of environmental samples with the Limulus Amebocyte Lysate (LAL) assay in a handheld device, known as the Lab-On-a-Chip Application Development Portable Test System (LOCAD-PTS). LOCADPTS was launched to the ISS in December 2006, and here we present data obtained from Mach 2007 until the present day. These data include a comparative study between LOCADPTS analysis and existing culture-based methods; and an exploratory survey of surface endotoxin and beta-1, 3-glucan throughout the ISS. While a general correlation between LOCAD-PTS and traditional culture-based methods should not be expected, we will suggest new requirements for microbial monitoring based upon culture-independent parameters measured by LOCAD-PTS.

Gunter, D.↗
DOE OSTI2013

Camptothecin inhibits platelet-derived growth factor-BB-induced proliferation of rat aortic vascular smooth muscle cells through inhibition of PI3K/Akt signaling pathway

The abnormal proliferation of vascular smooth muscle cells (VSMCs) in arterial wall is a major cause of vascular disorders such as atherosclerosis and restenosis after angioplasty. In this study, we investigated not only the inhibitory effects of camptothecin (CPT) on PDGF-BB-induced VSMC proliferation, but also its molecular mechanism of this inhibition. CPT significantly inhibited proliferation with IC50 value of 0.58 μM and the DNA synthesis of PDGF-BB-stimulated VSMCs in a dose-dependent manner (0.5–2 μM ) without any cytotoxicity. CPT induced the cell cycle arrest at G0/G1 phase. Also, CPT decreased the expressions of G0/G1-specific regulatory proteins including cyclin-dependent kinase (CDK)2, cyclin D1 and PCNA in PDGF-BB-stimulated VSMCs. Pre-incubation of VSMCs with CPT significantly inhibited PDGF-BB-induced Akt activation, whereas CPT did not affect PDGF-receptor beta phosphorylation, extracellular signal-regulated kinase (ERK) 1/2 phosphorylation and phospholipase C (PLC)-γ1 phosphorylation in PDGF-BB signaling pathway. Our data showed that CPT pre-treatment inhibited VSMC proliferation, and that the inhibitory effect of CPT was enhanced by LY294002, a PI3K inhibitor, on PDGF-BB-induced VSMC proliferation. In addition, inhibiting the PI3K/Akt pathway by LY294002 significantly enhanced the suppression of PCNA expression and Akt activation by CPT. These results suggest that the anti-proliferative activity of CPT is mediated in part by downregulating the PI3K/Akt signaling pathway. - Highlights: ► CPT inhibits proliferation of PDGF-BB-induced VSMC without cytotoxicity. ► CPT arrests the cell cycle in G0/G1 phase by downregulation of cyclin D1 and CDK2. ► CPT significantly attenuates Akt phosphorylation in PDGF-BB signaling pathway. ► LY294002 enhanced the inhibitory effect of CPT on VSMC proliferation. ► Thus, CPT is mediated by downregulating the PI3K/Akt signaling pathway.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2024

Effects of zero and reversed magnetic shear on resistive wall modes in a straight limiter tokamak with zero beta

Advanced tokamak scenarios often feature equilibriums with zero and reversed magnetic shear. To isolate and investigate their impacts on the resistive wall mode (RWM) instability analytically, we construct a series of cylindrical limiter equilibriums with different magnetic shear in the core and toward plasma edge, as a prototype of the configurations in advanced tokamak scenarios. Equilibriums with zero β are considered so that the analysis focuses on the current-driven RWMs. Analytical solutions for the n=1 resistive wall mode, derived from the reduced ideal magnetohydrodynamics (MHD) equations, consistently demonstrate key insights for both the core and the edge: the growth rate of RWMs is inversely proportional to the averaged magnetic shear when the safety factor at the edge (qa) is held constant. Specifically, an increase in positive averaged magnetic shear results in a decreased growth rate, whereas an increase in negative averaged magnetic shear leads to an increased growth rate. Furthermore, the influence of nqa on the mode's stability significantly surpasses the effects of magnetic shear changes previously discussed. These analytical calculation results provide a verification of NIMROD simulations.

Wan, Sui (ORCID:0009000464121677)↗
DOE OSTI2024

Global brain activity and its coupling with cerebrospinal fluid flow is related to tau pathology

Abstract INTRODUCTION Factors responsible for the deposition of pathological tau in the brain are incompletely understood. This study links macroscale tau deposition in the human brain to cerebrospinal fluid (CSF) flow dynamics using resting‐state functional magnetic resonance imaging (rsfMRI). METHODS Low‐frequency (< 0.1 Hz) resting‐state global brain activity is coupled with CSF flow and potentially reflects CSF dynamics‐related clearance. We examined the correlation between rsfMRI measures of CSF inflow and global activity (gBOLD–CSF coupling) as a predictor, interacting with amyloid beta (Aβ), of tau and cortical thickness (dependent variables) across Alzheimer's Disease Neuroimaging Initiative (ADNI) participants from cognitively unimpaired through mild cognitive impairment (MCI) and Alzheimer's disease (AD). RESULTS Tau deposition in Aβ+ participants, accompanied by cortical thinning and cognitive decline, is associated with decreased gBOLD–CSF coupling. Tau mediates the relationship between coupling and thickness. DISCUSSION Findings suggest that resting‐state global brain activity and CSF movements comodulate Alzheimer's tau deposition, presumably related to CSF clearance. Highlights A non‐invasive functional magnetic resonance imaging (fMRI) assessment of a CSF clearance‐related process is carried out. Global brain activity is coupled with CSF inflow in human fMRI during resting state. Global fMRI–CSF coupling is correlated with tau in Alzheimer's disease (AD). This coupling measure is also associated with cortical thickness, mediated by tau.

Neurosciences & Neurology↗
DOE OSTI2021

Vadose and Saturated Zone Flow and Transport Calculations for the Active Trenches of the Low-Level Burial Grounds, Hanford Site, Washington

The purpose of the fate and transport modeling described in this environmental calculation file (ECF) is to evaluate the impacts to groundwater associated with waste disposal operations at Mixed Waste Low-Level Burial Ground (LLBG) Trenches 31 and 34 to satisfy requirements in DOE O 435.1, Radioactive Waste Management. The model integrates the flow and transport in the vadose zone beneath the active trenches with the saturated zone downgradient of the trenches to predict the radionuclide concentration at the point of assessment (POA). DOE M 435.1-1, Radioactive Waste Management Manual, defines the POA as the point of highest projected dose or concentration beyond a 100 m (328 ft) buffer zone surrounding the disposed waste. The modeling is conducted in accordance with the DOE G 435.1, Implementation Guide for Use with DOE M 435.1-1, performance assessment (PA) guidelines. The modeling involves evaluation of the groundwater concentrations and radionuclide arrival times during the 1,000-year compliance and 10,000-year sensitivity-uncertainty periods per DOE O 435.1 and DOE M 435.1. This analysis does not consider radionuclide release during facility operations, only the post-closure impacts of the radionuclides to the environment. The evaluation of potential radiological dose to groundwater receptors caused by releases from a closed facility containing radioactive waste typically includes the following: (1) Release of radionuclides from that facility (2) Transport of those radionuclides through the environment, and (3) Exposure to humans to environmental concentration levels of those radionuclides The fate and transport three-dimensional (3D) model analysis involves the post-closure impacts to the environment of the technetium-99, iodone-129, and uranium (all isotopes in the waste). The residual inventory estimates include several radionuclides, but technetium-99 is typically responsible for almost all of the beta-gamma dose equivalent associated with groundwater (water resources) protection per 40 CFR 141, “National Primary Drinking Water Regulations” (e.g., see the results in WCH-520, Performance Assessment of Environmental Restoration Disposal Facility, Hanford Site, Washington; hereinafter referred to as the ERDF PA), and iodone-129 can also be a significant dose contributor for some waste (e.g., RPP-RPT-59958, Performance Assessment for the Integrated Disposal Facility, Hanford Site, Washington; hereinafter referred to as the IDF PA). Uranium does not typically factor significantly into the impacts to groundwater, even during the 10,000-year sensitivity-uncertainty period, but always remains of interest as a contaminant. This ECF does not address vadose and saturated zone modeling for Trench 94 of the 200 East Area LLBG. Current information confirms the validity of the low corrosion rate of the naval reactor plant carbon steel (HY-80), and the even lower corrosion rate of the nickel-iron-chromium alloy reactor vessel (Inconel Alloy 600) presented in DOE/EIS-0259, Final Environmental Impact Statement on the Disposal of Decommissioned, Defueled Cruiser, Ohio Class, and Los Angeles Class Naval Reactor Plants. Based on these low corrosion rates, the time to breach the reactor vessel to allow release of radionuclides from the activated metal of the reactor vessel internal structure is at least 10,000 years. This time to breach precludes the need to evaluate the vadose and saturated zone transport of contaminants released from the reactor compartment disposal packages in the 200 East Area LLBGs PA (CP-63826, Waste Release Model Package Report for the Active Trenches of the Low-Level Burial Grounds, Hanford Site, Washington).

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
NASA NTRS1993

Detergent solubilization of the EGF receptor from A431 cells

Functional reconstitution of purified preparations of human epidermal growth factor receptor (EGFR) requires dissociation of the protein from its plasma membrane lipid environment. Solubilization of membrane proteins in this manner requires the use of detergents, which are known to disrupt plasma membrane lipid/protein interactions. We have investigated the ability of three nonionic detergents to solubilize the human EGFR selectively, and have also analyzed the effect of these various treatments on the intrinsic tyrosyl kinase activity of the receptor. The nonionic detergent known as n-octyl glucoside (n-octyl beta-D-glucopyranoside) was found to give the best combination of selectivity, yield, and maintenance of enzymatic activity of the human EGFR.

Non-NASA Center↗
DOE OSTI2015

Transcription factor FOXA2-centered transcriptional regulation network in non-small cell lung cancer

Lung cancer is the leading cause of cancer-mediated death. Although various therapeutic approaches are used for lung cancer treatment, these mainly target the tumor suppressor p53 transcription factor, which is involved in apoptosis and cell cycle arrest. However, p53-targeted therapies have limited application in lung cancer, since p53 is found to be mutated in more than half of lung cancers. In this study, we propose tumor suppressor FOXA2 as an alternative target protein for therapies against lung cancer and reveal a possible FOXA2-centered transcriptional regulation network by identifying new target genes and binding partners of FOXA2 by using various screening techniques. The genes encoding Glu/Asp-rich carboxy-terminal domain 2 (CITED2), nuclear receptor subfamily 0, group B, member 2 (NR0B2), cell adhesion molecule 1 (CADM1) and BCL2-associated X protein (BAX) were identified as putative target genes of FOXA2. Additionally, the proteins including highly similar to heat shock protein HSP 90-beta (HSP90A), heat shock 70 kDa protein 1A variant (HSPA1A), histone deacetylase 1 (HDAC1) and HDAC3 were identified as novel interacting partners of FOXA2. Moreover, we showed that FOXA2-dependent promoter activation of BAX and p21 genes is significantly reduced via physical interactions between the identified binding partners and FOXA2. These results provide opportunities to understand the FOXA2-centered transcriptional regulation network and novel therapeutic targets to modulate this network in p53-deficient lung cancer. - Highlights: • Identification of new target genes of FOXA2. • Identifications of novel interaction proteins of FOXA2. • Construction of FOXA2-centered transcriptional regulatory network in non-small cell lung cancer.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2016

Prolyl hydroxylase-1 regulates hepatocyte apoptosis in an NF-κB-dependent manner

Hepatocyte death is an important contributing factor in a number of diseases of the liver. PHD1 confers hypoxic sensitivity upon transcription factors including the hypoxia inducible factor (HIF) and nuclear factor-kappaB (NF-κB). Reduced PHD1 activity is linked to decreased apoptosis. Here, we investigated the underlying mechanism(s) in hepatocytes. Basal NF-κB activity was elevated in PHD1{sup −/−} hepatocytes compared to wild type controls. ChIP-seq analysis confirmed enhanced binding of NF-κB to chromatin in regions proximal to the promoters of genes involved in the regulation of apoptosis. Inhibition of NF-κB (but not knock-out of HIF-1 or HIF-2) reversed the anti-apoptotic effects of pharmacologic hydroxylase inhibition. We hypothesize that PHD1 inhibition leads to altered expression of NF-κB-dependent genes resulting in reduced apoptosis. This study provides new information relating to the possible mechanism of therapeutic action of hydroxylase inhibitors that has been reported in pre-clinical models of intestinal and hepatic disease. -- Highlights: •Genetic ablation of PHD1 upregulates NF-kappaB (NF-κB) in hepatocytes. •Activation of NF-κB leads to differential DNA-binding of p50/p65 and results in differential regulation of apoptotic genes. •We identified proline 191 in the beta subunit of the I-kappaB kinase as a target for PHD1-mediated hydroxylation. •Blockade of prolyl-4-hydroxylases has been found cytoprotective in liver cells.

60 APPLIED LIFE SCIENCES↗