Spectral Analysis Program Research Articles

Application of FEFF to the x-ray spectroscopy of cerium dioxide

The spectral analysis program FEFF has been used to address a series of x-ray spectroscopic results from cerium based materials. Specifically, the experimental results of the M4,5 x-ray emission spectroscopy (XES) of γ-Ce, the M4,5 x-ray absorption spectroscopy of γ-Ce, and the L3 XAS of CeO2 are simulated with FEFF, with varying degrees of success. Cerium’s role as a surrogate for Pu is introduced and the strengths and shortcomings of the FEFF computational results will be noted.

The Estill Voice Model: A paradigm for voice training and treatment

For over 40 years, the Estill Voice Model (EVM) has defined voice quality according to movement of anatomy and physiology. EVM addresses the daunting degrees of freedom issue in voice motor control by isolating Craft of voice production from Artistry and Performance Metaphysics. The EVM proposes an integrated implicit-explicit approach for voice motor learning that flows through all training and therapy protocols. Implicit instructions include auditory-perceptual prompts (e.g., quack like a duck to produce “twang”) and explicit prompts train physiologic conditions of the vocal anatomy correlated with the voice quality (e.g., narrow your aryepiglottic sphincter to produce “twang”). Estill exercises address power, source, and filter properties of voice production, and include narrowing the aryepiglottic sphincter for “ring” in opera and belt and for increased power in hypofunctional voices, and varying vocal fold mass for register shifts and optimizing contact for hyperfunctional voices. Patients learn to feel, see, and hear the voice via multiple feedback modes including hand gestures, magnitude estimation of bodily kinesthetic effort, visual acoustic cues in real-time spectral analysis programs. This presentation will highlight objective measurement science and clinical evidence for using Estill exercises in treatment for all voices, from the novice speaker to the expert performer.

The effects of hypercortisolism on the frequency and magnitude of sleep EEG waves in patients with Cushing syndrome: A spectral analysis study

ObjectivesOur aim was to investigate the effects of endogenous chronic hypercortisolism on sleep electroencephalogram (EEG) and differences between the adrenocorticotropic hormone (ACTH)-dependent and independent Cushing Syndrome (CS) patients through a sleep spectral analysis program. MethodsA total of 32 patients diagnosed as having endogenous CS (12 ACTH-dependent and 20 ACTH-independent) and a control group comprising 16 healthy individuals were included in the study. Polysomnographic analysis was performed. Blood samples were collected at 08:00 AM for analysis of ACTH and basal cortisol, and at 00:00 AM for midnight cortisol levels. The frequency and power of the slow wave activity (SWA), theta, alpha, and beta waves of the first and last non-rapid eye movement (NREM) cycles were measured with a spectral analysis program. ResultsThe CS patient group had higher SWA power, especially in the first NREM cycle. In the ACTH-dependent group, SWA maximum and mean power values were higher in the frontal channels in the first NREM, compared to the last NREM sleep stage (p<0.05). ConclusionCortisol has been found to be associated with SWA waves, making these waves higher in power, especially in the first NREM phase. This difference was much less pronounced in the final NREM sleep stage. The difference between the first and last NREM sleep stages with respect to the power of SWA in the frontal channel in the ACTH-dependent group suggests that not only cortisol but also high levels of ACTH affect the power of slow waves during sleep.

Hyperfine structure studies of neutral praseodymium with Fourier transform spectroscopy

The hyperfine structure patterns of some neutral praseodymium (Pr I) lines in the range of 2969 − 34998 cm−1 were investigated based on the archival data from the Fourier transform spectrometer at the US National Solar Observatory. The hyperfine magnetic dipole interaction constants A are presented by fitting the spectra with our spectral analysis program. The HFS constants A for 56 levels of Pr I from 0.0 to 27602.42 cm−1 were determined.

Recovering Age–Metallicity Distributions from Integrated Spectra: Validation with MUSE Data of a Nearby Nuclear Star Cluster

Abstract Current instruments and spectral analysis programs are now able to decompose the integrated spectrum of a stellar system into distributions of ages and metallicities. The reliability of these methods has rarely been tested on nearby systems with resolved stellar ages and metallicities. Here we derive the age–metallicity distribution of M54, the nucleus of the Sagittarius dwarf spheroidal galaxy, from its integrated Multi-Unit Spectroscopic Explorer (MUSE) spectrum. We find a dominant old (8–14 Gyr), metal-poor (−1.5 dex) component and a young (1 Gyr), metal-rich (+0.25 dex) component—consistent with the complex stellar populations measured from individual stars in the same MUSE data set. There is excellent agreement between the (mass-weighted) average age and metallicity of the resolved and integrated analyses. Differences are only 3% in age and 0.2 dex metallicity. By co-adding individual stars to create M54's integrated spectrum, we show that the recovered age–metallicity distribution is insensitive to the magnitude limit of the stars or the contribution of blue horizontal branch stars—even when including additional blue wavelength coverage from the WiFeS Atlas of Galactic Globular cluster Spectra survey. However, we find that the brightest stars can induce the spurious recovery of an old (&gt;8 Gyr), metal-rich (+0.25 dex) stellar population, which is otherwise not expected from our understanding of chemical enrichment in M54. The overall derived stellar mass-to-light ratio of M54 is M/L V = 1.46 with a scatter of 0.22 across the field of view, which we attribute to the stochastic contribution of a young, metal-rich component. These findings provide strong evidence that complex stellar population distributions can be reliably recovered from integrated spectra of extragalactic systems.

A new spray deposition pattern measurement system based on spectral analysis of a fluorescent tracer

To complement shortages of discrete sampling data and improve the detection accuracy of droplet deposition in unmanned aerial vehicle (UAV) spraying, we developed a new spray deposition pattern measurement system (SDPMS) based on a fluorescent tracer and spectral analysis. Then, we evaluated the system performance in two field spraying experiments in comparison with water-sensitive paper results. The system comprises a fluorescence scanner and spectral analysis program. The fluorescence scanner includes an ultraviolet light, spectrometer, far end controller, stepping motor, and sample reel. First, 1.0% fluorescent tracer solution is sprayed, and the droplets are collected on a paper strip. Then, the paper strip is scanned with the fluorescence scanner, and a set of fluorescence intensity values is collected and processed by the spectral analysis program. Finally, the spray deposition pattern is calculated. The experimental results showed that the spray deposition pattern from the SDPMS had a 0.89 correlation coefficient with that of water-sensitive paper. A linear regression model between fluorescence intensity and deposit coverage was constructed, with a coefficient of determination of 0.91 (F = 61.8845, P < 0.001). In addition, a linear regression model between fluorescence intensity and volume rate was constructed, with a coefficient of determination of 0.89 (F = 51.6639, P < 0.001). The SDPMS and field experiments offer a good foundation for the development of an improved system compatible with UAV spraying.

Advanced Spectral Analysis Program.

Advanced Spectral Analysis Program is a LabVIEW-based program intended for rapid and accurate analysis of large sets of spectral data. It can handle a range of different types of data including angle-resolved and energy-dispersive powder diffraction and Raman spectra. We present it here with a focus on high-temperature high-pressure powder diffraction. The program contains a novel graphical user interface that allows rapid manual fitting and indexing of peaks which require precise fitting ranges and includes tools for fitting any Bravais lattice and arbitrary user-defined multivariate equations of state. The program allows the user to simultaneously view and manipulate multiple data sets from an experiment. The user can save and load analysis progress at any point, allowing for repeatable calculations to be performed, and to allow the fast comparison of different analysis parameters.

66. Results of a spectrometric analysis performed at the ASST Lariana on 223Ra-dichloruro Xofigo

Purpose BAYER has recently marketed a pharmaceutical named Xofigo, consisting of 223Ra-dichloride, for the treatment of metastatic bone lesions of castration-resistant prostate cancer. Its production modality consists of the neutron irradiation of a 226Ra target yielding 227Ac which, through intermediate steps, decays into 223Ra. In view of the possible presence of radionuclide impurities that may demand strong radiation protection requirements (e.g. 227Ac and 226Ra), a radiometric analysis of Xofigo was performed to rule out any contamination by other long-lived radioisotopes [1] . Methods The spectrometry system consisted of the GEM-20 P EG&G ORTEC Hyperpure Germanium detector, the ORTEC TRIUMP-PCI-8 k multichannel analyzer, the ORTEC GammaVision spectral analysis program, and two certified calibration point sources (152Eu and 241Am). A 0.2 ml volume of radiopharmaceutical (about 200 kBq activity) was inserted into a conical test tube and the gamma emission spectrum was acquired. The detection efficiency was calculated by a dedicated application (ORTEC ANGLE v.3.0), integrated with the GammaVision software. The spectral analysis was performed by means of a specific library, containing both expected and suspected radioisotopes. Results The spectral acquisitions (see Figure) and the related analysis (see Table) were repeated to test the reproducibility of the results and provided the following outcomes: the calculated 223Ra activity was (196 ± 9) kBq, in agreement with the one measured at sampling, and the 211Bi and 219Rn activities were absolutely compatible with the transient equilibrium condition with the 223Ra father. No radionuclides other than those expected were found above the minimum detectable activity (MDA). Conclusions Any significant presence of radioisotope contamination in the radiopharmaceutical sample and, consequently, of issues related to long-lived radionuclides, can be excluded, ensuring both the operator and the patient protection and the safe management of the radioactive waste. Download : Download high-res image (262KB) Download : Download full-size image

완전통계 피로해석법을 이용한 모스 LNG 운반선 수명 연장에 관한 리뷰

Fatigue analysis for life extension of a ship is different from that of a newly constructed ship since the current corrosion margin and voyage routes of the past and future must be considered, thereby complicating the life extension procedure. This research introduces the fatigue analysis case for the life extension project of a moss LNG carrier using full spectral fatigue analysis, which has been previously used for newly constructed ships. It is expected that the fatigue analysis methodologies and full spectral fatigue analysis program used in this study will be applicable to other life extension projects.

PIXE-quantified AXSIA: Elemental mapping by multivariate spectral analysis

Automated, nonbiased, multivariate statistical analysis techniques are useful for converting very large amounts of data into a smaller, more manageable number of chemical components (spectra and images) that are needed to describe the measurement. We report the first use of the multivariate spectral analysis program AXSIA (Automated eXpert Spectral Image Analysis) developed at Sandia National Laboratories to quantitatively analyze micro-PIXE data maps. AXSIA implements a multivariate curve resolution technique that reduces the spectral image data sets into a limited number of physically realizable and easily interpretable components (including both spectra and images). We show that the principal component spectra can be further analyzed using conventional PIXE programs to convert the weighting images into quantitative concentration maps. A common elemental data set has been analyzed using three different PIXE analysis codes and the results compared to the cases when each of these codes is used to separately analyze the associated AXSIA principal component spectral data. We find that these comparisons are in good quantitative agreement with each other.

Conformational isomerism in 1-heptanal

The rotational spectrum of 1-heptanal has been recorded over the 10–22 GHz region using a pulsed-molecular-beam, Fourier transform microwave spectrometer. The spectrum has been analyzed using the jb95 spectral analysis program. The spectra of 13 conformational isomers have been identified and assigned in the rich soup of observed transitions. Transitions of these isomers have relative intensities that are well above the intensity level of the onset of 13C isotopomers, which are a factor of 100 down in intensity. In addition to the above 13 isomers, two additional spectra were identified and assigned that belong to dimers that consist of 1-heptanal and one water molecule. In order to map the observed spectra to conformational geometries, high-level ab initio calculations have been carried out. All 15 observed conformers have been associated with ab initio determined structure configurations. In general, the agreement in rotational constants and dipole intensity pattern between the ab initio results and the experimentally observed spectra is quite good.

Prediction of fatty acid content in rabbit meat and discrimination between conventional and organic production systems by NIRS methodology

To investigate the feasibility of using the NIRS methodology to analyse the fatty acid content of rabbit meat and to discriminate between conventional and organic production, the meat of a hind leg of 119 rabbits was scanned between 1100 and 2498 nm and 104 samples were sent to the laboratory for reference analysis of fatty acids by gas chromatography. A commercial spectral analysis program (WINISI-2, v. 1.04) was used to process the data and to develop chemometric models. The better calibration equation for each fatty acid, leading to a higher determination coefficient of cross-validation ( r 2) and low standard error of cross-validation (SECV) was retained. Prediction of linoleic, palmitic, palmitoleic and oleic acid content was excellent or good ( r 2 between 0.90 and 0.70); prediction of arachidonic, stearic, α-linolenic and eicosatrienoic FA has r 2 between 0.69 and 0.50. However, miristic, vaccenic, icosaenoic and eicosadienoic FA are problematic to predict. When fatty acids were grouped, the r 2 of the calibration equations were: 0.85 for saturated FA, 0.83 for MUFA, 0.92 for PUFA and 0.91 for n − 6 FA, indicating excellent or good prediction. Prediction of α-linolenic FA ( r 2 = 0.59) needs more precision. The obtained equations have been applied for predicting meat fatty acid composition of both groups of production systems, conventional and organic, for an other 52 rabbit meat samples (2 × 26). Meat of the organic source had lower ( p = 0.000) monounsaturated FA (30.54% vs. 34.64%) and higher ( p = 0.019) polyunsaturated FA (27.28% vs. 23.66%) than rabbit meat from the conventional system, while the saturated FA content was similar (42%) in both groups. The discriminant model correctly classified (98%) between conventional or organic produced rabbit meat.

A comparison of velocity- and wavelet-based tube-wave suppression methods

Velocity-based filters, namely the f − k filter and the τ − p filter, were applied to suppress tube-wave noise in a borehole data gather recorded near the Gulf Coast of Louisiana. In comparison, wavelet-based filters, namely the median filter and the spatial derivative filter (i.e., subtraction filter), were also applied to the data. Attenuation measurements were made by using a spectral analysis program. Both velocity-based filters reduced tube waves by a factor of 6.5 with minimal distortion to the signal. In contrast, the median filter and the subtraction filter reduced tube waves by factors of 8.6 and 7.9, respectively, but caused noticeable signal distortion.

Effect of bulky lesions on DNA: solution structure of a DNA duplex containing a cholesterol adduct.

The three-dimensional solution structure of two DNA decamers of sequence d(CCACXGGAAC)-(GTTCCGGTGG) with a modified nucleotide containing a cholesterol derivative (X) in its C1 '(chol)alpha or C1 '(chol)beta diastereoisomer form has been determined by using NMR and restrained molecular dynamics. This DNA derivative is recognized with high efficiency by the UvrB protein, which is part of the bacterial nucleotide excision repair, and the alpha anomer is repaired more efficiently than the beta one. The structures of the two decamers have been determined from accurate distance constraints obtained from a complete relaxation matrix analysis of the NOE intensities and torsion angle constraints derived from J-coupling constants. The structures have been refined with molecular dynamics methods, including explicit solvent and applying the particle mesh Ewald method to properly evaluate the long range electrostatic interactions. These calculations converge to well defined structures whose conformation is intermediate between the A- and B-DNA families as judged by the root mean square deviation but with sugar puckerings and groove shapes corresponding to a distorted B-conformation. Both duplex adducts exhibit intercalation of the cholesterol group from the major groove of the helix and displacement of the guanine base opposite the modified nucleotide. Based on these structures and molecular dynamics calculations, we propose a tentative model for the recognition of damaged DNA substrates by the UvrB protein.

NvAssign: protein NMR spectral assignment with NMRView

Nuclear magnetic resonance (NMR) protein studies rely on the accurate assignment of resonances. The general procedure is to (1) pick peaks, (2) cluster data from various experiments or spectra, (3) assign peaks to the sequence and (4) verify the assignments with the spectra. Many algorithms already exist for automating the assignment process (step 3). What is lacking is a flexible interface to help a spectroscopist easily move from clustering (step 2) to assignment algorithms (step 3) and back to verification of the algorithm output with spectral analysis (step 4). A software module, NvAssign, was written for use with NMRView. It is a significant extension of the previous CBCA module. The module provides a flexible interface to cluster data and interact with the existing assignment algorithms. Further, the software module is able to read the results of other algorithms so that the data can be easily verified by spectral analysis. The generalized interface is demonstrated by connecting the clustered data with the assignment algorithms PACES and MONTE using previously assigned data for the lyase domain of DNA polymerase lambda. The spectral analysis program NMRView is now able to read the output of these programs for simplified analysis and verification. NvAssign is available from http://dir.niehs.nih.gov/dirnmr/nvassign

On the Absorption of X‐Rays in the Interstellar Medium

We present an improved model for the absorption of X-rays in the ISM intended for use with data from future X-ray missions with larger effective areas and increased energy resolution such as Chandra and XMM, in the energy range above 100eV. Compared to previous work, our formalism includes recent updates to the photoionization cross section and revised abundances of the interstellar medium, as well as a treatment of interstellar grains and the H2molecule. We review the theoretical and observational motivations behind these updates and provide a subroutine for the X-ray spectral analysis program XSPEC that incorporates our model.

Crystallographic and NMR analysis of 9-phenylthiophenanthrene and 9-tert-butylthiophenanthrene

The crystal structures of 9-phenylthiophenanthrene (C20H14S) and 9-tert-butylthiophenanthrene (C18H18S) were determined at 193 K. The former crystallizes in orthorhombic space group P212121 (No. 19) with cell dimensions a = 5.602(2), b = 9.247(3), and c = 27.508(12) Å and the latter in orthorhombic space group Pbcn (No. 60) with cell parameters a = 21.335(4), b = 7.540(2), and c = 18.197(4) Å. In both compounds the substituents at sulfur are nearly perpendicular to the phenanthrene plane. NMR spectra of the compounds were recorded in CDCl3. The 1H NMR spectral parameters were analyzed in detail by using an iterative spectral analysis program. The 13C{1H} resonances were fully assigned with the aid of two-dimensional heteronuclear chemical shift correlation spectra. On the basis of the NOE difference spectra the orientation of the side chain was concluded to be similar to that in the solid state.

A portable, photon analysis spectrometer for the assay of X- and gamma-ray emitting radionuclides

A portable, battery-powered, multichannel analyzer (MCA) for use with Ge spectrometers has been developed for in-field use for the assay of x-and γ-ray emitting radionuclides. The spectrometer is capable of operating to rates greater than 150,000 counts per second. The analyzer is a Canberra InSpector MCA, that is equipped with the INEEL ultra-stable dual-energy pulser, and pulse injection with subsequent removal (PISR) circuitry. PCGAP, a set of MCA control and spectral analysis programs, was developed for use on a PC with a Windows NT Operating System. It includes an interactive peak analysis program as well as automatic spectral analysis programs for the X- and γ-ray regions, and a number of utility programs. The pulser peaks are calibrated with radioactive sources in terms of energy (i.e., their energy equivalents are measured) using the PCGAP spectral analysis package so that energy shifts, including those due to changes in temperature or count rate, do not cause a loss of energy calibration. The number of injected low- and high-energy-equivalent pulses is known so the stored pulser pulses can be used for a dead-time and random summing correction. The pulser peaks are also used to monitor any deterioration in spectral quality caused by noise, ground loops, etc. The results of performance tests to demonstrate the capabilities of this pulser-equipped InSpector are reported.

Measuring the oxidation of heme compounds in heart homogenates from rats supplemented with dietary antioxidants

Protection by antioxidant nutrients against oxidative damage in rat heart homogenates was studied. Following spontaneous oxidation of heart homogenates from rats fed vitamin E, selenium, or β-carotene, oxidized heme proteins (OHP) and thiobarbituric acid reactive substances (TBARS) were measured. The absorbance spectra of oxidized and reduced heme proteins were analyzed with a heme spectral analysis program (HSAP) developed in this laboratory. HSAP is a multicomponent analysis program that uses successive approximations and computer spreadsheet solver functions to deconvolute a complex absorbance spectrum into individual heme protein spectra. Vitamin E markedly decreased formation of OHP, and vitamin E, selenium, or β-carotene significantly lowered the production of TBARS during spontaneous oxidation of heart homogenates compared with homogenates from rats fed antioxidant-deficient diets. Pyridine hemochrome analysis showed that the total amounts of heme proteins present in the homogenates decreased during the oxidative incubation period. The formation of OHP correlated significantly with the amount of TBARS produced and could be simulated as a function of the oxidative and protective reactions involved in the oxidation of rat heart homogenates. Copyright © 1996 Elsevier Science Inc.

NMR characterization of obscurinervine and obscurinervidine using novel computerized analysis techniques

The 13C and 1H resonances of the alkaloids, obscurinervine (1) and obscurinervidine (2), are assigned using high-field NMR experiments and computerized data analysis procedures. A 2D INADEQUATE analysis of 26 mg of 2 was performed with a high-sensitivity carbon probe and the data interpreted using the spectral analysis program, CCBOND, to provide unambiguous 13C assignments. Although all signals are visually undetectable, CCBOND determined 20 of the 22 carbon–carbon bonds present. Corresponding 1H chemical shift assignments are made from HETCOR data. Proton–proton couplings are determined from DQF-COSY data using the new analysis program, HHCORR. Since HHCORR models signals as AB spin systems, the determined coupling constants are fairly independent of higher order effects, linewidths and digital resolution. Also a significant sensitivity improvement over visual interpretation of DQF-COSY data is observed. The obtained coupling constants are interpreted through the Karplus relationship to provide conformational details. These novel software analysis techniques allow accurate and more routine analysis of INADEQUATE and DQF-COSY data providing non-specialists access to these powerful experiments. Absolute stereochemistry of 2 is determined by a comparison with the ORD curve of(–)-O-methylaspidolimine. Stereospecific 1H assignments are obtained from proton–proton couplings and molecular mechanics simulations. The 13C and 1H chemical shift assignments for the related alkaloid, obscurinervine 1, are determined from CCBOND processed 2D INADEQUATE, HHCORR processed DQF-COSY, and HETCOR data. Differences in the rigidity of 1 and 2 in dimethyl sulfoxide (DMSO) are quantified by variable-temperature 1H NMR spectroscopy. Complete conformations of all ring systems are obtained from molecular mechanics using dihedral angles derived from proton–proton couplings as a check on the quality of the model. All conformational conclusions are independently supported by the X-ray structure of 1.