Similarity analysis for thermal signature comparison in metal additive manufacturing
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Chandrasekar, Sujana↗
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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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Analysis of mutational signatures in exomes from B-cell lymphoma cell lines suggest APOBEC3 family members to be involved in the pathogenesis of primary effusion lymphoma
Here, primary effusion lymphoma (PEL) is a rare large B-cell neoplasm particularly affecting immunodeficient hosts with an increased incidence in young or middle-aged males infected with the HIV. 1 The clinical outcome of patients with PEL is unfavorable with a median survival of <6 months. 1 PEL has been closely associated with human herpes virus 8 (HHV8, previously called Kaposi sarcoma herpesvirus) infection. 1 In some cases a coinfection of HHV8 with the Epstein–Barr Virus (EBV) has been described. 1 HHV8 encodes various genes homologous to cellular genes that have proliferative and anti-apoptotic functions. 2 Although HHV8 is supposed to be a major driver of PEL, it alone is not sufficient for a full-blown lymphomagenesis. 2 PEL usually shows complex karyotypes with many chromosomal aberrations. 3 This chromosomal complexity might be driven by the viral infection and lead to genetic alterations cooperating with HHV8 in PEL lymphomagenesis. 4
59 BASIC BIOLOGICAL SCIENCES↗
Stratigraphic Analysis of Microseismic Signatures during Hydraulic Stimulation
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Earth Sciences↗
Wheat signature modeling and analysis for improved training statistics: Supplement. Simulated LANDSAT wheat radiances and radiance components
Simulated scanner system data values generated in support of LACIE (Large Area Crop Inventory Experiment) research and development efforts are presented. Synthetic inband (LANDSAT) wheat radiances and radiance components were computed and are presented for various wheat canopy and atmospheric conditions and scanner view geometries. Values include: (1) inband bidirectional reflectances for seven stages of wheat crop growth; (2) inband atmospheric features; and (3) inband radiances corresponding to the various combinations of wheat canopy and atmospheric conditions. Analyses of these data values are presented in the main report.
Malila, W. A.↗
Quantitative Analysis of Topographic Signatures for Geomorphic Applications
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topographic earth science remote sensing data geom↗
Gamma/neutron analysis for SNM signatures at high-data rates(greater than 107 cps) for single-pulse active interrogation
We are developing a high data gamma/neutron spectrometer suitable for active interrogation of special nuclear materials (SNM) activated by a single burst from an intense source. We have tested the system at Naval Research Laboratory's (NRL) Mercury pulsed-power facility at distances approaching 10 meters from a depleted uranium (DU) target. We have found that the gamma-ray field in the target room 'disappears' 10 milliseconds after the x-ray flash, and that gamma ray spectroscopy will then be dominated by isomeric states/beta decay of fission products. When a polyethylene moderator is added to the DU target, a time-dependent signature of the DU is produced by thermalized neutrons. We observe this signature in gamma-spectra measured consecutively in the 0.1-1.0 ms time range. These spectra contain the Compton edge line (2.2 MeV) from capture in hydrogen, and a continuous high energy gamma-spectrum from capture or fission in minority constituents of the DU.
08 HYDROGEN↗
Water quality parameter measurement using spectral signatures
Regression analysis is applied to the problem of measuring water quality parameters from remote sensing spectral signature data. The equations necessary to perform regression analysis are presented and methods of testing the strength and reliability of a regression are described. An efficient algorithm for selecting an optimal subset of the independent variables available for a regression is also presented.
White, P. E.↗
Genetic Analysis of the Full-Length gag Gene from the Earliest Korean Subclade B of HIV-1: An Outbreak among Korean Hemophiliacs
We determined the earliest full-length HIV-1 gag gene sequences in 110 patients with HIV-1, including 20 hemophiliacs (HPs) and 90 local controls (LCs). The gag gene from stored sera was amplified using RT-PCR, and was subjected to direct sequencing. Phylogenetic analysis indicated that 94 and 16 sequences belonged to the Korean subclade of HIV-1 subtype B (KSB) and subtype B, respectively. A total of 12 signature pattern amino acids were found within the KSB, distinct from the worldwide consensus of subtype B. Within the KSB, the gag gene sequences from donors O and P and those from the 20 HPs comprised two subclusters. In particular, sequences from donor O strongly clustered with those of eight HPs. Moreover, signature pattern analysis indicated that 14 signature nucleotides were shared between the HPs and LCs within KSB (p < 0.01). Among the 14 nucleotides, positions 9 and 5 belonged to clusters O and P, respectively. In conclusion, signature pattern analysis for the gag gene revealed 12 signature pattern residues within the KSB and also confirmed the previous conclusion that the 20 HPs were infected with viruses due to incompletely inactivated clotting factor IX. This study is the first genetic analysis of the HIV-1 gag gene in Korea.
59 BASIC BIOLOGICAL SCIENCES↗
Limitations on wind-tunnel pressure signature extrapolation
Analysis of some recent experimental sonic boom data has revived the hypothesis that there is a closeness limit to the near-field separation distance from which measured wind tunnel pressure signatures can be extrapolated to the ground as though generated by a supersonic-cruise aircraft. Geometric acoustic theory is used to derive an estimate of this distance and the sample data is used to provide a preliminary indication of practical separation distance values.
Mack, Robert J.↗
Possible signatures of dissipation from time-series analysis techniques using a turbulent laboratory magnetohydrodynamic plasma
The frequency spectrum of magnetic fluctuations as measured on the Swarthmore Spheromak Experiment is broadband and exhibits a nearly Kolmogorov 5/3 scaling. It features a steepening region which is indicative of dissipation of magnetic fluctuation energy similar to that observed in fluid and magnetohydrodynamic turbulence systems. Two non-spectrum based time-series analysis techniques are implemented on this data set in order to seek other possible signatures of turbulent dissipation beyond just the steepening of fluctuation spectra. Presented here are results for the flatness, permutation entropy, and statistical complexity, each of which exhibits a particular character at spectral steepening scales which can then be compared to the behavior of the frequency spectrum.
70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
A Monte Carlo Technique to Estimate Emissions from R&D Facilities
The Pacific Northwest National Laboratory (PNNL) operates multidisciplinary laboratory Research and Development (R&D) facilities for the U. S. Department of Energy and sampled air chemical emissions from some of these facilities from 1998 until 2008. Although sampling was not required for environmental compliance, PNNL conducted sampling to provide data to compare estimated release fractions to those used for emissions estimates and to verify that methods used to determine compliance with air regulations and permits conservatively predict actual emissions. Sampling also identifies and quantifies air toxics emitted to compare with compliance limits established by the State. The sampling data provides a unique opportunity to quantify emissions and investigate factors potentially impacting emissions. Previous work using this data set include a paper by Woodruff, Benar, and McCarthy1 who summarized the compliance approach used by PNNL and described sampling and analytical measurements for the first sampling campaigns. Conclusions reported in the paper were that none of the measurements of the target compounds exceeded a State acceptable source impact level (ASIL)2 even using significant overestimation factors, and that an average release fraction calculated from the data provided reasonable validation of the factor used in compliance assessments. Other reports using the data include the following: • A metric was developed by Ballinger, Duchsherer, and Metoyer3 to compare chemical signatures. The analysis found similarities in chemical signatures from three of the buildings but a markedly different signature from the fourth building. • A method was developed and used on the data to rank the chemical compounds that present the greatest risk to a potential downstream receptor and to determine whether the sampling parameters and detection limits provided sufficient resolution to verify compliance at potential receptor locations.4 • The stack data from one of the buildings was analyzed using a statistical technique called Positive Matrix Factorization (PMF) to identify the number and composition of major contributing sources to measured stack concentrations.5 In this analysis, a method is described that uses a Monte Carlo technique to produce a distribution of emission estimates from the measured data. The method is applied to one of the chemicals previously identified as more significant than others using the ranking process.4 Variations on the method are investigated and compared to determine their effects on the emission estimates.
Laboratory, air chemical emissions, volatile organ↗
A static acoustic signature system for the analysis of dynamic flight information
The Army family of helicopters was analyzed to measure the polar octave band acoustic signature in various modes of flight. A static array of calibrated microphones was used to simultaneously acquire the signature and differential times required to mathematically position the aircraft in space. The signature was then reconstructed, mathematically normalized to a fixed radius around the aircraft.
Ramer, D. J.↗
Characteristic vector analysis as a technique for signature extraction of remote ocean color data
Characteristic vector analysis is being used to extract spectral signatures of suspended matter in the ocean from remote ocean color data collected with MOCS (Multichannel Ocean Color Sensor), a multispectral scanner. Spectral signatures appear to be obtainable either directly from characteristic vectors or through a transformation of these eigenvectors. Quantification of the suspended matter associated with each resulting signature seems feasible using associated coefficients generated by the technique. This paper presents eigenvectors associated with algae, 'sediment', acid waste, sewage sludge, and oil. The results suggest an efficient method of transmitting from satellites multispectral data of pollution in our oceans.
Grew, G. W.↗
An Analysis of Measured Pressure Signatures From Two Theory-Validation Low-Boom Models
Two wing/fuselage/nacelle/fin concepts were designed to check the validity and the applicability of sonic-boom minimization theory, sonic-boom analysis methods, and low-boom design methodology in use at the end of the 1980is. Models of these concepts were built, and the pressure signatures they generated were measured in the wind-tunnel. The results of these measurements lead to three conclusions: (1) the existing methods could adequately predict sonic-boom characteristics of wing/fuselage/fin(s) configurations if the equivalent area distributions of each component were smooth and continuous; (2) these methods needed revision so the engine-nacelle volume and the nacelle-wing interference lift disturbances could be accurately predicted; and (3) current nacelle-configuration integration methods had to be updated. With these changes in place, the existing sonic-boom analysis and minimization methods could be effectively applied to supersonic-cruise concepts for acceptable/tolerable sonic-boom overpressures during cruise.
Mack, Robert J.↗
A discussion of dynamic stability measurement techniques
Techniques for the measurement of the dynamic stability of linear systems are discussed. Particular attention is given to an analysis of the errors in the procedures, and to methods for calculating the system damping from the data. The techniques discussed include: transient decay, moving block analysis, spectral analysis, random decrement signatures, transfer function analysis, and parameter identification methods. The special problems of rotorcraft dynamic stability testing are discussed.
Johnson, W.↗
Time-dependent behavioral data from zebrafish reveals novel signatures of chemical toxicity using point of departure analysis
High-content imaging of embryonic zebrafish behavior can be used as a screening approach to rapidly evaluate the relative potential for chemicals to cause toxicity. However, most statistical methods applied to these data so far transform movement values to incidence-based “hits” and calculate lowest effect levels (LELs), which loses individual fish resolution of behavior and defies hazard ranking due to reliance on applied dose levels. Here, we have developed and parallelized a workflow to calculate benchmark dose (BMD) values from dynamic, high-content zebrafish behavior data that scales for high-throughput chemical screening. To appropriately capture the dynamics of zebrafish response from light to dark stimulus, we summarized time-dependent data using both area under the curve and immediate change at the transition point into two novel metrics that characterized abnormal behavior as a function of chemical concentration. The BMD workflow was applied to calculate BMD 10 values of 1,060 ToxCast chemicals for 24 zebrafish endpoints, including behavior, mortality and morphology. The BMD 10 values provided better precision and separation than LELs for clustering chemicals since they were derived from models that best-fit their concentration-response curves. Clustering analysis revealed behavioral signatures as the most sensitive endpoints. High concordance in chemical activity was observed between ToxCast assays and zebrafish behavioral endpoints, however ToxPi analysis indicated that rankings based on in vitro data was not a reliable predictor of in vivo rankings for lower potency chemicals. The methods developed in this work will enable the use of high-content zebrafish behavioral screening data for BMD analysis in toxicological hazard assessment.
59 BASIC BIOLOGICAL SCIENCES↗
Rotor Magnet Fault Analysis in Permanent Magnet AC Machines Under Load Conditions - All Electric Transportation Systems
This paper studies the performance of a Permanent Magnet (PM) alternating-current (AC) machine when subjected to faults under load conditions. The effect of varying load torques, and unbalances are found to be potential causes of rotor faults, inducing physical magnet defects or broken rotor-PMs. The consequent and immediate impact on the machine quantities is observed through anomalous change in torque-speed characteristics and other vital signatures such as machine back-EMF/flux and motor current signatures (MCS). The present research study develops and illustrates a method to diagnose physical magnet defects (fault) in PMAC machines by estimating the machine torque/back-EMF constant, Ke. The constant Ke is a measure of magnet strength exhibiting the health of rotor PMs, indicative of faults. Advanced research studies and investigations are carried out to establish motor approximations and signature-based analysis as significant viable tools for diagnosing machine faults even under load conditions.
alternating current↗
Integrative epigenomic analysis reveals unique epigenetic signatures involved in unipotency of mouse female germline stem cells
Background: Germline stem cells play an essential role in establishing the fertility of an organism. Although extensively characterized, the regulatory mechanisms that govern the fundamental properties of mammalian female germline stem cells remain poorly understood. Results: We generate genome-wide profiles of the histone modifications H3K4me1, H3K27ac, H3K4me3, and H3K27me3, DNA methylation, and RNA polymerase II occupancy and perform transcriptome analysis in mouse female germline stem cells. Comparison of enhancer regions between embryonic stem cells and female germline stem cells identifies the lineage-specific enhancers involved in germline stem cell features. Additionally, our results indicate that DNA methylation primarily contributes to female germline stem cell unipotency by suppressing the somatic program and is potentially involved in maintenance of sexual identity when compared with male germline stem cells. Moreover, we demonstrate down-regulation of Prmt5 triggers differentiation and thus uncover a role for Prmt5 in maintaining the undifferentiated status of female germline stem cells. Conclusions: The genome-wide epigenetic signatures and the transcription regulators identified here provide an invaluable resource for understanding the fundamental features of mouse female germline stem cells.
59 BASIC BIOLOGICAL SCIENCES↗