bluuebunny/crossref_metadata_2025 huggingface dataset:
Least-Squares Curve Fitting of near Infrared Spectra Predicts Protein and Moisture Content of Ground Wheat
Authors: Hruschka William R. , Norris Karl H.
Published: August 2005

Near infrared (log 1/reflectance) spectra of samples of ground wheat were approximated by a linear combination of spectra of known constituents, the approximation satisfying a least-squares criterion. The appropriate coefficients of these linear combinations were then linearly correlated with the protein and moisture content of the samples. Two extensions of previously reported curve-fitting techniques were made. First, multilinearly correlating several of the curve fit coefficients with the chemical data improved the standard errors. Second, using sample spectra as components, rather than pure constituent spectra, improved the standard errors to a point where they became comparable to those obtained by currently used derivative methods. The samples covered a protein range of 10 to 19%. Correlation coefficients reached 0.998 for protein, corresponding to a standard error of prediction of 0.15%. Parameters examined included spectral region, smoothing, and wavelength shifting. Results with reflectance spectra of sample sets with large particle size variation and high noise are also reported.
Orientation Measurements from Polymer Surfaces Using Fourier Transform Infrared Photoacoustic Spectroscopy
Authors: Krishnan K. , Hill S. , Hobbs J. P. , Sung C. S. P.
Published: August 2005

Fourier transform IR photoacoustic (FT-IR-PAS) dichroism studies have been applied to determine molecular orientation from the surface of one-way drawn poly(ethylene terephthalate) film. When compared with attenuated total internal reflectance (ATR) dichroic spectra obtained with a modified, rotatable sample holder on the same sample, photoacoustic (PA) spectra show saturation effects in strong absorption bands near 1730, 1250, and 1100 cm−1, probably due to the greater penetration depth in the PA technique. The dichroic ratios ( kx/ky) on the plane of the sample film have been calculated from PA spectra, only on bands which do not show saturation and compared with the analogous ratios determined from ATR dichroic spectra. For three well-known parallel bands at 1335, 975, and 795 cm−1 the dichroic ratio is greater than unity in both ATR and PAS, as expected from the drawing process. In general, somewhat lower dichroic ratios are observed by PA spectra than by ATR spectra with this sample. Possible reasons for this trend are discussed. This study demonstrates the potential of FT-IR-PAS dichroism as a complementary technique to ATR dichroism, especially on samples with rough or brittle surfaces.
Saturation and Prefilter Distortions of Observed Excitation Spectral Profiles
Authors: Piepmeier E. H. , Beenen G. J.
Published: August 2005

When the wavelength of a laser is tuned across a spectral line, the spectral positions of the observed peaks of the absorption, fluorescence, or ionization signals may be distorted by saturation and prefilter effects. Theoretical models are presented which predict the spectral shifts that may occur when there is an asymmetry in either the line or laser spectral profiles. Examples are presented that show the appearance of an extra peak, and a dramatic shift equal in magnitude to the half-width of a profile. Spectral broadening is predicted for both symmetric and asymmetric spectral profiles. Line reversal is a predicted prefilter effect, in the absence of saturation. Saturation and prefilter effects are treated separately to emphasize their individual characteristics.
Spectrophotometric Analysis by Cross-Correlation
Authors: Mann C. K. , Goleniewski J. R. , Sismanidis C. A.
Published: August 2005

An examination of the use of cross-correlation in quantitative analysis under conditions that isolated peaks are not obtained is reported. Examples are taken from infrared absorption spectroscopy. The properties of correlation that are relevant to this application are described. A comparison between cross-correlation and peak measurement is made with emphasis on the effects of sample background and instrument noise. Results are presented to show that correlation allows substantial improvement of performance when spectra with complex backgrounds are involved. It affords a significant improvement when noisy signals must be handled.
Infrared Laser-Induced Thermal Lens Calorimetry
Authors: Carter C. A. , Brady J. M. , Harris J. M.
Published: August 2005

Thermal lens calorimetry is applied to the measurement of infrared absorption of condensed phase samples. The unique trade offs encountered with longer wavelength lasers in thermal lens measurements are discussed. As a demonstration of the technique, the determination of hydrocarbons using a helium-neon laser operated at 3.39 μm is reported. The minimum detectable sample has an absorbance, A = 5 × 10−4, corresponding to 8 ng of 2,2,4-trimethylpentane within the beam volume in the sample. Interpretation of absorbance at the helium-neon laser transition is aided by the determination of functional group molar absorptivities from a series of normal, cyclic, and branched-chain hydrocarbons. The average specific absorption coefficient for hydrocarbons at this wavelength is found to be 2.09 (±0.09) 1 g−1 cm−1.
NMR Investigations on Liquid Metallic Bulk and Particle Samples
Authors: Ploumbidis D.
Published: August 2005

Measurements of the Knight shift of 115In in liquid indium have been carried out over the temperature range of 420 to 1350 K, using bulk and particle samples. The results observed with the different forms of sample are in reasonable agreement. Therefore, bulk samples seem to be preferable for NMR studies in all those cases where droplet preparation is difficult. A theoretical investigation of the detection sensitivity and NMR signal form of bulk samples is presented.
Laser-Enhanced Ionization Flame Velocimeter
Authors: Schenck P. K. , Travis J. C. , Turk G. C. , O'Haver T. C.
Published: August 2005

The temporal and spatial evolution of the depleted neutral atom density following laser-enhanced ionization in laminar flow flames has been used to characterize the flow velocity of the flame gases. This technique utilizes a low power cw dye laser and a low sodium seed density (1011 to 1012 atoms/ml). The flow velocity can be measured to better than 2% in standard analytical burners.
Effects of Aerosol Introduction on the Analytical Utility of dc Plasma Jets
Authors: Coleman Geoffrey N. , Allen Alexander M.
Published: August 2005

Large aerosol introduction tubes are shown to affect adversely analytical calibration curves and apparent ion-to-atom intensity ratios in two-electrode dc plasma jets. With large chimneys, the aerosol that skirts the plasma results in substantial ground state atom concentrations along the optical axis between the source and detector. The use of excited ion emission lines for analysis circumvents most of the adverse effects.
Calibration Curve Preparation of Analytes in Liquid Solutions by Means of an Exponential Dilution Flask
Authors: Inman E. L. , Voigtman E. , Winefordner J. D.
Published: August 2005

An exponential dilution flask for liquid solutions is evaluated for automated calibration curve preparation and detection limit determination by spectroscopic methods. Linearity of the log concentration vs time plot is found to approach 5 orders of magnitude. Design parameters have been selected for use as a routine laboratory system.
Some Pattern Recognition Considerations for Low-Temperature Luminescence and Room Temperature Fluorescence Spectra
Authors: Sogliero Gene , Eastwood Delyle , Ehmer Robert
Published: August 2005

Low-temperature (77 K) luminescence (LTL) and room temperature fluorescence (RTF) spectra of polynuclear aromatic hydrocarbons with varying amounts of spectral structure are studied as a function of several instrument parameters (emission slit width, scan speed, and damping) in order to develop quantitative criteria for spectral quality and reproducibility. The purpose of this study is to assess the classification and pattern recognition capabilities for hazardous chemicals for various spectral techniques and to develop suitable spectral libraries and search routines. In order to quantitate the effect of the instrument parameters on the spectrum, a statistic (power) was used to measure spectral quality. In addition, three measures of similarity, used for assessing the agreement between two patterns (spectra), were evaluated to determine the variability that can be expected in spectra obtained under the same and different instrumental conditions. Analysis of the data confirms that the low-temperature luminescence technique produces better quality spectra than the room temperature fluorescence technique, but that room temperature fluorescence spectra are more repeatable.
Direct Aerosol Introduction in Constant-Temperature Furnace Atomic Absorption Spectroscopy
Authors: Jenke Dennis R. , Woodriff Ray
Published: August 2005

Combination of a sample introduction/desolvation system with a Woodriff-type constant temperature furnace atomizer allows for the rapid, direct analysis of aqueous samples with precisions comparable to and detection limits 5 times lower than those obtained by conventional flame analysis. The introduction system consists of a pneumatic nebulizer, a spray chamber for collection of large aerosol particles, a heated chamber for solvent evaporation, and a condenser for solvent removal. Under optimized operating conditions, detection limits obtainable for Ag, Cd, Zn, and Pb are 0.14, 0.50, 0.64, and 8.3 ppb, respectively, whereas precision at a concentration level 50 times the detection limit is 2.7%, 5.3%, 7.0%, and 5.5% relative standard deviation. The system is relatively free from chloride and nitrate matrix interferences, whereas interferences resulting from the presence of 1% sulfate and phosphate ions appear to be related to the nebulization process and can be greatly reduced by modification of these conditions.
Effects of Air-Acetylene Flame Parameters on Simultaneous Multielement Atomic Absorption Spectrometry
Authors: Harnly James M. , Kane Jean S. , Miller-Ihli Nancy J.
Published: August 2005

The effects of the air-acetylene ratio and the observation height on the detection limits and analytical accuracy of 11 elements (Ca, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, and Zn) determined by simultaneous multielement atomic absorption spectrometry with a continuum source (SIMAAC) were investigated. Determinations were made at four observation heights and five airacetylene ratios evenly spaced over normal ranges for these variables. For the 11 elements, detection limits and characteristic concentrations varied by factors of 1.5 to 25. The best compromise detection limits were obtained at observation heights low in the flame and with richer flames. The variations of the analytical recoveries for Co, Cr, Cu, Fe, K, Mg, Na, and Zn determined in a National Bureau of Standards (NBS) standard reference material (SRM) and two United States Geological Survey (USGS) standard rocks as a function of the flame parameters were relatively insignificant. Significant variations were observed for Ca and Mg, whereas the concentration of Ni was too low to permit any conclusions. The optimal, compromise flame parameters, for analytical accuracy, were the two lowest observation heights in lean flames when all elements except Ca and Mg were determined. Inclusion of Mg shifted the optimal parameters to a higher observation height. Four NBS SRM's and three USGS standard rocks were analyzed weekly, over a 7-week period, at a low observation height in a lean air-acetylene flame. In general, accuracies within ±5% of 100% and precisions of ±5% were obtained for Co, Cr, Cu, Fe, K, Mn, Na, and Zn. Acceptable recovery (100% ± 5%) for Ca could only be obtained with a large dilution of the sample into a 0.5% La matrix.
Computer-Assisted Spectral Identification of Unknown Mixtures
Authors: Gillette P. C. , Lando J. B. , Koenig J. L.
Published: August 2005

Procedures are described which permit the qualitative analysis of spectral mixtures by using factor analysis in conjunction with a spectral reference library.
A Computerized Research Microdensitometer for Spectrographic Data Analysis
Authors: Grandy Mark E. , Sainz Mario A. , Coleman David M.
Published: August 2005

A research grade microdensitometer has been modified and updated with a linear optical encoder to monitor and control accurately photographic plate position and digitized read out of density data. This measurement system is fully interfaced to a Data General time-shared computer network. Plate position is controlled to within ±0.0001 in. (0.0025 mm) via a closed-loop computer, stepper motor, and incremental linear optical encoder system. Plate movement and density sampling are under computer control with resulting data stored on disc memory for later analysis. Program techniques, including error analysis, have been developed to determine unknown wavelengths to within ±0.006 Å from spectral dispersion data fit to third-order polynomials. Analytical implications, especially relating to sequential multi-element analysis, are discussed. The completed instrument may be applied to a variety of spectroscopic and nonspectroscopic problems.
Detection of Transient Spectra within Polycrystalline Samples Using the New Technique of Diffuse Reflectance Flash Photolysis
Authors: Kessler R. W. , Oelkrug D. , Wilkinson F.
Published: August 2005

A powdered semiconductor (ZnO) and a polycrystalline sample of perovskite-type LaAIO3 doped with 1% Cr(III) have been subjected to the recently developed technique of diffuse reflectance flash photolysis. In both cases transient absorption spectra are obtained from these powdered, nontransparent samples and these are reported here. Thus, the method allows the direct observation of absorption by transient species formed following pulsed irradiation within powdered samples as well as from highly scattering interfaces demonstrating that the technique has high potential for investigating heterogeneous photochemical systems.
Surface Spectroscopic Analysis of HCN/NH3 Corrosion Products on Iron by Fourier Transform Infrared Photoacoustic Spectroscopy and X-ray Photoelectron Spectroscopy
Authors: Gardella Joseph A. , Eyring Edward M. , Klein Joseph C. , Carvalho Manuel B.
Published: August 2005

Surface analysis of the corrosion products formed on iron metal exposed to off gas from a HCN production process has been performed. The atmosphere contains HCN(g), NH3(g), and H2O(g) plus other trace gases. Iron gratings exposed to the atmosphere form a dark blue coating which pits the surface of the iron. Samples of the corroded iron surface were analyzed by FT-IR/photoacoustic spectroscopy (PAS) and x-ray photoelectron spectroscopy (XPS or ESCA). The mid-IR spectrum from PAS yielded peaks due to NH4+, CN−, and H2O. ESCA analysis confirmed that the surface iron was divalent, coordinated to cyanide, and no iron(II) oxide was present. Relative quantitation from ESCA showed a 1:4 ratio of NH4/CN type nitrogen, thus a specific single stoichiometry was not postulated for the corrosion product. Peak positions of the cyanide stretching frequencies suggest a mixed ferro(ferrocyanide) complex, with some ammonium as a counterion. This study illustrates the detailed structural information obtainable from FT-IR/PAS with ESCA and the applicability of FT-IR/PAS to corrosion problems.
Infrared Group Frequency Data for Diphenoquinones
Authors: Nyquist R. A.
Published: August 2005

The 3,3′,5,5′-tetraalkyl-4,4′-diphenoquinones exhibit their most intense IR band near 1600 cm−1, and is assigned to a complex mode involving out-of-phase (C=O)2 stretching. A combination tone assigned as in-phase (C=0)2 stretching and out-of-phase stretching suggests that the frequency separation between the two (C=O)2 stretching modes is small. Other characteristic group frequencies are also discussed.
ICP Spectra: I. Background Emission
Authors: Forster A. R. , Anderson T. A. , Parsons M. L.
Published: August 2005

The background spectra originating from an ICP excitation source using a standard set of conditions have been tabulated and classified from 2075 to 6005 Å. These data were acquired using a high-resolution, scanning echelle monochromator capability of 0.01 Å. Background features include 205 Ar transitions; atomic spectra from H, C, and Si; and molecular band emission from the OH species. Possible spectral interferences of analysis lines with this background spectra were discussed and tabulated for first through third order overlaps.
Developments for High-Speed Analysis of Diverse Ferrous Alloys
Authors: Washburn D. Neil , Walters John P.
Published: August 2005

High-power positionally stabilized sparks were used to sample several types of ferrous alloys. The power was increased by sparking at repetition rates up to 1920 sparks/s and peak discharge currents up to 800 A. The signal/background ratios of several spectral lines were measured photographically and photoelectrically, while the power was varied and the number of coulombs held constant. The coulombs were measured by gated integration of the discharge current waveform. Analysis time decreased by a factor of 16 while the signal/background ratio for sample spectral lines decreased by a factor of 2.5.
Synchronous Luminescence Spectroscopy: Methodology and Applicability
Authors: Vo-Dinh Tuan
Published: August 2005

This paper discusses the figures of merit associated with the synchronous luminescence (SL) technique in multicomponent analysis of complex samples. Spectral interferences and experimental factors that influence the choice of experimental conditions are investigated. The efficacy of SL is demonstrated in the direct determination of anthracene and 2-methylanthracene in a raw coal liquid. The application of the second-derivative technique to the SL measurement of organic samples is shown. Special emphasis is directed toward the applicability of the SL technique as a practical and cost-effective screening procedure in the routine analysis of complex organic samples.
Stability of Rapid Scanning Interferometers
Authors: De Haseth James A.
Published: August 2005

An investigation is made to measure errors and instabilities associated with interferometric spectrometers. All data analysis is performed using the time or distance domain signal (interferogram) to eliminate any anomalies produced by transformation to spectral data. Three basic tests were performed which involved variations of the centerburst amplitude, the interferogram sampling offset and signal stability. These tests were performed on raw data and after all nonzero phase had been removed from the interferometric signal. All errors measured are extremely small, but are larger than ideal detector-limited noise. This paper does not attempt to identify all potential instabilities associated with interferometers, but presents methods by which instabilities can be measured and quantified on a relative basis.
Application of Factor Analysis to the Resolution of Overlapping XPS Spectra
Authors: Gilbert R. A. , Llewellyn J. A. , Swartz W. E. , Palmer J. W.
Published: August 2005

Factor analysis has been used to resolve the overlapping XPS spectra obtained in the x-ray-induced transformation of Pt(en)2(OH)2Cl2 to Pt(en)2Cl2. This is achieved without prior knowledge of the data set nor the establishment of any initial curve fitting criteria.
High-Voltage Spark Atomic Emission Detector for Gas Chromatography
Authors: Calkin Clayton L. , Koeplin Sandra M. , Crouch S. R.
Published: August 2005

A dc-powered, double-gap, miniature nanosecond spark source for emission spectrochemical analysis of gas chromatographic effluents is described. The spark is formed between two thoriated tungsten electrodes by the discharge of a coaxial capacitor. The spark detector is coupled to the gas chromatograph by a heated transfer line. The gas chromatographic effluent is introduced into the heated spark chamber where atomization and excitation of the effluent occurs upon breakdown of the analytical gap. A microcomputer-controlled data acquisition system allows the implementation of time-resolution techniques to distinguish between the analyte emission and the background continuum produced by the spark discharge. Multiple sparks are computer averaged to improve the signal-to-noise ratio. The application of the spark detector for element-selective detection of metals and nonmetals is reported.
Preliminary Evaluation of the Effects of Quenching and Inner-Filter on the Ratio Deconvolution of Fluorescence Data
Authors: Fogarty Michael P. , Warner Isiah M.
Published: August 2005

The theory for the use of quenching as an aid in the ratio deconvolution of multicomponent fluorescence data is discussed. The advantage of quenching is that apparent changes in the relative fluorescence intensity of the components can be accomplished without extensive sample preparation. The disadvantage is that most quenchers exhibit significant absorption in the range of excitation wavelengths used for studying many fluorescent analytes. This absorption produces an attenuation of the excitation beam through an “inner-filter” mechanism. The problems associated with inner-filter effects are discussed.
Instrumental Distortions of Raman Lines
Authors: Arora A. K. , Umadevi V.
Published: August 2005

The effect of spectrometer resolution on the peak intensity and the full width at half maximum (FWHM) of a Lorentzian spectrum is obtained by evaluating the convoluted line shapes. Spectrometer resolution functions (SRF) having Gaussian and triangular profiles are considered separately. Empirical relations to estimate the true peak intensity and the FWHM from the observed parameters are suggested. These relations are valid over an extended range of parameters with an accuracy better than that of other methods suggested earlier. As an application, the true FWHM's and peak intensities of the main component of the Raman active Ag mode of sulphate ion in potash alum at low temperatures are evaluated.
Application of PAS for the Investigation of Overtones and Combinations in the near IR
Authors: Natale Michael , Lewis Larry N.
Published: August 2005

The photoacoustic spectrometer (PAS) used in the near IR region is shown to be useful for observing the combinations and overtones of strong IR fundamentals. Overtones and combinations of the carbonyls in Mo(CO)6, Ir4(CO)12, and [RhCl(CO)2]2 are observed. Carbonyl and ring (C—H, C—C) fundamental overtones and combinations from (C6H6)Cr(CO)3 are observed in the near IR. The near IR PAS is shown to be useful for analyzing surface constituents on silicon. An overtone and combination due to bound H2O is identified on silicon by comparison to the near IR PAS spectrum of H2O and D2O. The C—N overtone band due to ferro- and ferricyanide is observed in the near IR by PAS. The spectrum of ferricyanide deposited on silicon is used to identify the surface changes that occur on a silicon photoelectrochemical cell coated with ferricyanide.
Analysis of Barium and Strontium in Sediments by dc Plasma Emission Spectrometry
Authors: Bowker P. C. , Manheim F. T.
Published: August 2005

The dc plasma arc is suited to analysis of barium and strontium in a wide range of sedimentary rock matrices, from sands, shales, and carbonates, to ferromanganese nodules. Samples containing 10 ppm to more than 3000 ppm barium and strontium were studied. Both alkali (3500 ppm lithium borate, from a preliminary fusion) and lanthanum salts (1%) in the final solution are needed to achieve freedom from systematic effects due to extreme variation in matrix. In the absence of La, neither Li, Na, K, nor Cs totally eliminated effects of Al and other constituents on emission. Silica addition to the fusion helps achieve proper flux viscosity to aid removal of fused beads from graphite crucibles. The effect of refractory-substance formers such as aluminum with calcium can be reduced or removed by selection of a portion of the arc for emission measurement. However, it was decided not to pursue this approach because of loss in analytical sensitivity and need for greater precision in optical adjustment. Analysis of standard rock samples showed generally satisfactory agreement with precision methods of analysis, and some new standard rock data are reported.
Performance of Some Regenerated Hollow Cathode Lamps for Atomic Absorption Spectrometry
Authors: Parker W. C. , Lozada R. , LaBrecque J. J.
Published: August 2005

Some preliminary results are reported for recuperated hollow cathode lamps in a demountable system as used in atomic absorption spectrometry. The lamps recuperated consisted of the following elements: magnesium, aluminum, chromium, copper, zinc, and selenium. Each lamp was cut open, modified according to its requirements, and mounted in a demountable system. The sensitivities and emission spectra of each lamp were compared with their commercial equivalent.
Direct Quantification of Analyte Concentration by Resonant Acoustic Profiling
Authors: Godber Benjamin , Thompson Kevin SJ , Rehak Marian , Uludag Yildiz , Kelling Sven , Sleptsov Alexander , Frogley Mark , Wiehler Klaus , Whalen Christopher , Cooper Matthew A
Published: August 2005

Background: Acoustic sensors that exploit resonating quartz crystals directly detect the binding of an analyte to a receptor. Applications include detection of bacteria, viruses, and oligonucleotides and measurement of myoglobin, interleukin 1β (IL-1β), and enzyme cofactors.

Methods: Resonant Acoustic Profiling™ was combined with a microfluidic lateral flow device incorporating an internal reference control, stable linker chemistry, and immobilized receptors on a disposable sensor “chip”. Analyte concentrations were determined by analyzing the rate of binding of the analyte to an appropriate receptor.

Results: The specificity and affinity of antibody–antigen and enzyme–cofactor interactions were determined without labeling of the receptor or the analyte. We measured protein concentrations (recombinant human IL-1β and recombinant human myoglobin) and quantified binding of cofactors (NADP+ and NAD+) to the enzyme glucose dehydrogenase. Lower limits of detection were ∼1 nmol/L (17 ng/mL) for both IL-1β and human myoglobin. The equilibrium binding constant for NADP+ binding to glucose dehydrogenase was 2.8 mmol/L.

Conclusions: Resonant Acoustic Profiling detects analytes in a relatively simple receptor-binding assay in <10 min. Potential applications include real-time immunoassays and biomarker detection. Combination of this technology platform with existing technologies for concentration and presentation of analytes may lead to simple, label-free, high-sensitivity methodologies for reagent and assay validation in clinical chemistry and, ultimately, for real-time in vitro diagnostics.
Development and Calibration of a TDR Extensometer for Geotechnical Monitoring
Authors: Lin CP , Tang SH
Published: August 2005

Up-hole reflectometry devices that interrogate passive mechanical transducers are increasingly used in geotechnical instrumentation. One of such a monitoring technique is the time domain reflectometry (TDR). This study utilizes the principle of TDR to devise a TDR extensometer using a waveguide with an impedance mismatch interface inside it. The movement of the impedance mismatch interface is coupled with the displacement of interest such that the time shift in the reflected signal becomes a measure of the displacement. The accuracy of the TDR extensometer is better than ± 0.5 mm and is not affected by measuring range and cable length. It can be used for applications that require both high accuracy and large displacement range, and is suitable for long-term monitoring in a harsh environment where humidity and lightening surge may cause problems for electronic sensors. The devised extensometer can be combined with existing TDR transducers for groundwater pressure and shear deformation to form an integrated TDR monitoring system for slope stability.
Comparison of Dental Maturity in Children of Different Ethnic Origins: International Maturity Curves for Clinicians
Authors: Chaillet N , Nyström M , Demirjian A
Published: August 2005

Dental maturity was studied with 9577 dental panoramic tomograms of healthy subjects from 8 countries, aged between 2 and 25 years of age. Demirjian's method based on 7 teeth was used for determining dental maturity scores, establishing gender-specific tables of maturity scores and development graphs. The aim of this study was to give dental maturity standards when the ethnic origin is unknown and to compare the efficiency and applicability of this method to forensic sciences and dental clinicians. The second aim was to compare the dental maturity of these different populations. We noted an high efficiency for International Demirjian's method at 99%CI (0.85% of misclassified and a mean accuracy between 2 to 18 years ± 2.15 years), which makes it useful for forensic purposes. Nevertheless, this international method is less accurate than Demirjian's method developed for a specific country, because of the inter-ethnic variability obtained by the addition of 8 countries in the dental database. There are inter-ethnic differences classified in three major groups. Australians have the fastest dental maturation and Koreans have the slowest.
Rate of Gene Transfer From Mitochondria to Nucleus: Effects of Cytoplasmic Inheritance System and Intensity of Intracellular Competition
Authors: Yamauchi Atsushi
Published: August 2005

Endosymbiotic theory states that mitochondria originated as bacterial intracellular symbionts, the size of the mitochondrial genome gradually reducing over a long period owing to, among other things, gene transfer from the mitochondria to the nucleus. Such gene transfer was observed in more genes in animals than in plants, implying a higher transfer rate of animals. The evolution of gene transfer may have been affected by an intensity of intracellular competition among organelle strains and the organelle inheritance system of the organism concerned. This article reveals a relationship between those factors and the gene transfer rate from organelle to nuclear genomes, using a mathematical model. Mutant mitochondria that lose a certain gene by deletion are considered to replicate more rapidly than normal ones, resulting in an advantage in intracellular competition. If the competition is intense, heteroplasmic individuals possessing both types of mitochondria change to homoplasmic individuals including mutant mitochondria only, with high probability. According to the mathematical model, it was revealed that the rate of gene transfer from mitochondria to the nucleus can be affected by three factors, the intensity of intracellular competition, the probability of paternal organelle transmission, and the effective population size. The gene transfer rate tends to increase with decreasing intracellular competition, increasing paternal organelle transmission, and decreasing effective population size. Intense intracellular competition tends to suppress gene transfer because it is likely to exclude mutant mitochondria that lose the essential gene due to the production of lethal individuals.
The Rank Ordering of Genotypic Fitness Values Predicts Genetic Constraint on Natural Selection on Landscapes Lacking Sign Epistasis
Authors: Weinreich Daniel M
Published: August 2005

Sewall Wright's genotypic fitness landscape makes explicit one mechanism by which epistasis for fitness can constrain evolution by natural selection. Wright distinguished between landscapes possessing multiple fitness peaks and those with only a single peak and emphasized that the former class imposes substantially greater constraint on natural selection. Here I present novel formalism that more finely partitions the universe of possible fitness landscapes on the basis of the rank ordering of their genotypic fitness values. In this report I focus on fitness landscapes lacking sign epistasis (i.e., landscapes that lack mutations the sign of whose fitness effect varies epistatically), which constitute a subset of Wright's single peaked landscapes. More than one fitness rank ordering lacking sign epistasis exists for L > 2 (where L is the number of interacting loci), and I find that a highly statistically significant effect exists between landscape membership in fitness rank-ordering partition and two different proxies for genetic constraint, even within this subset of landscapes. This statistical association is robust to population size, permitting general inferences about some of the characteristics of fitness rank orderings responsible for genetic constraint on natural selection.
ThecsnD/csnESignalosome Genes Are Involved in theAspergillus nidulansDNA Damage Response
Authors: Lima Joel Fernandes , Malavazi Iran , von Zeska Kress Fagundes Marcia Regina , Savoldi Marcela , Goldman Maria Helena S , Schwier Elke , Braus Gerhard H , Goldman Gustavo Henrique
Published: August 2005

The signalosome (CSN) is a conserved multiprotein complex involved in regulation of eukaryotic development and is also required to activate ribonucleotide reductase for DNA synthesis. In Aspergillus nidulans, csnD/csnE are key regulators of sexual development. Here, we investigated whether the csnD/csnE genes are involved in the DNA damage response in this fungus. The growth of the csnD/csnE deletion mutants was reduced by subinhibitory concentrations of hydroxyurea, camptothecin, 4-nitroquinoline oxide, and methyl methanesulfonate. A. nidulans increases csnD/csnE mRNA levels when it is challenged by different DNA-damaging agents. There is no significant transcriptional induction of the csnE promoter fused with lacZ gene in the presence of DNA-damaging agents, suggesting that increased mRNA accumulation is due to increased mRNA stability. Septation was not inhibited in the csnD/csnE deletion mutants while ΔuvsB ΔcsnE presented an increase in septation upon DNA damage caused by methyl methanesulfonate, suggesting that uvsBATR and csnE genetically interact during checkpoint-dependent inhibition of septum formation. The double ΔcsnD/ΔcsnE ΔnpkA mutants were more sensitive to DNA-damaging agents than were the respective single mutants. Our results suggest that csnD/csnE genes are involved in the DNA damage response and that NpkA and UvsBATR genetically interact with the signalosome.
Modeling Early Epstein-Barr Virus Infection in Drosophila melanogaster: The BZLF1 Protein
Authors: Adamson Amy L , Wright Natasha , LaJeunesse Dennis R
Published: August 2005

Epstein-Barr virus (EBV) is the causative agent of infectious mononucleosis and is associated with several forms of cancer, including lymphomas and nasopharyngeal carcinoma. The EBV immediate-early protein BZLF1 functions as a transcriptional activator of EBV early gene expression and is essential for the viral transition between latent and lytic replication. In addition to its role in the EBV life cycle, BZLF1 (Z) also has profound effects upon the host cellular environment, including disruption of cell cycle regulation, signal transduction pathways, and transcription. In an effort to understand the nature of Z interactions with the host cellular environment, we have developed a Drosophila model of early EBV infection, where we have expressed Z in the Drosophila eye. Using this system, we have identified a highly conserved interaction between the Epstein-Barr virus Z protein and shaven, a Drosophila homolog of the human Pax2/5/8 family of genes. Pax5 is a well-characterized human gene involved with B-cell development. The B-cell-specific Pax5 also promotes the transcription of EBV latent genes from the EBV Wp promoter. Our work clearly demonstrates that the Drosophila system is an appropriate and powerful tool for identifying the underlying genetic networks involved in human infectious disease.
Association Mapping of Kernel Size and Milling Quality in Wheat (Triticum aestivum L.) Cultivars
Authors: Breseghello Flavio , Sorrells Mark E
Published: August 2005

Association mapping is a method for detection of gene effects based on linkage disequilibrium (LD) that complements QTL analysis in the development of tools for molecular plant breeding. In this study, association mapping was performed on a selected sample of 95 cultivars of soft winter wheat. Population structure was estimated on the basis of 36 unlinked simple-sequence repeat (SSR) markers. The extent of LD was estimated on chromosomes 2D and part of 5A, relative to the LD observed among unlinked markers. Consistent LD on chromosome 2D was <1 cM, whereas in the centromeric region of 5A, LD extended for ∼5 cM. Association of 62 SSR loci on chromosomes 2D, 5A, and 5B with kernel morphology and milling quality was analyzed through a mixed-effects model, where subpopulation was considered as a random factor and the marker tested was considered as a fixed factor. Permutations were used to adjust the threshold of significance for multiple testing within chromosomes. In agreement with previous QTL analysis, significant markers for kernel size were detected on the three chromosomes tested, and alleles potentially useful for selection were identified. Our results demonstrated that association mapping could complement and enhance previous QTL information for marker-assisted selection.
Chromosome Complement of the Fungal Plant Pathogen Fusarium graminearum Based on Genetic and Physical Mapping and Cytological Observations
Authors: Gale L R , Bryant J D , Calvo S , Giese H , Katan T , O'Donnell K , Suga H , Taga M , Usgaard T R , Ward T J , Kistler H C
Published: August 2005

A genetic map of the filamentous fungus Fusarium graminearum (teleomorph: Gibberella zeae) was constructed to both validate and augment the draft whole-genome sequence assembly of strain PH-1. A mapping population was created from a cross between mutants of the sequenced strain (PH-1, NRRL 31084, originally isolated from Michigan) and a field strain from Minnesota (00-676, NRRL 34097). A total of 111 ascospore progeny were analyzed for segregation at 235 loci. Genetic markers consisted of sequence-tagged sites, primarily detected as dCAPS or CAPS (n = 131) and VNTRs (n = 31), in addition to AFLPs (n = 66) and 7 other markers. While most markers exhibited Mendelian inheritance, segregation distortion was observed for 25 predominantly clustered markers. A linkage map was generated using the Kosambi mapping function, using a LOD threshold value of 3.5. Nine linkage groups were detected, covering 1234 cM and anchoring 99.83% of the draft sequence assembly. The nine linkage groups and the 22 anchored scaffolds from the sequence assembly could be assembled into four chromosomes, leaving only five smaller scaffolds (59,630 bp total) of the nuclear DNA unanchored. A chromosome number of four was confirmed by cytological karyotyping. Further analysis of the genetic map data identified variation in recombination rate in different genomic regions that often spanned several hundred kilobases.
Multiple Genes Affect Sensitivity of Caenorhabditis elegans to the Bacterial Pathogen Microbacterium nematophilum
Authors: Gravato-Nobre Maria J , Nicholas Hannah R , Nijland Reindert , O'Rourke Delia , Whittington Deborah E , Yook Karen J , Hodgkin Jonathan
Published: August 2005

Interactions with bacteria play a major role in immune responses, ecology, and evolution of all animals, but they have been neglected until recently in the case of C. elegans. We report a genetic investigation of the interaction of C. elegans with the nematode-specific pathogen Microbacterium nematophilum, which colonizes the rectum and causes distinctive tail swelling in its host. A total of 121 mutants with altered response to infection were isolated from selections or screens for a bacterially unswollen (Bus) phenotype, using both chemical and transposon mutagenesis. Some of these correspond to known genes, affecting either bacterial adhesion or colonization (srf-2, srf-3, srf-5) or host swelling response (sur-2, egl-5). Most mutants define 15 new genes (bus-1–bus-6, bus-8, bus-10, bus-12–bus-18). The majority of these mutants exhibit little or no rectal infection when challenged with the pathogen and are probably altered in surface properties such that the bacteria can no longer infect worms. A number have corresponding alterations in lectin staining and cuticle fragility. Most of the uninfectable mutants grow better than wild type in the presence of the pathogen, but the sur-2 mutant is hypersensitive, indicating that the tail-swelling response is associated with a specific defense mechanism against this pathogen.
A Statistical Multiprobe Model for Analyzing cis and trans Genes in Genetical Genomics Experiments With Short-Oligonucleotide Arrays
Authors: Alberts Rudi , Terpstra Peter , Bystrykh Leonid V , de Haan Gerald , Jansen Ritsert C
Published: August 2005

Short-oligonucleotide arrays typically contain multiple probes per gene. In genetical genomics applications a statistical model for the individual probe signals can help in separating “true” differential mRNA expression from “ghost” effects caused by polymorphisms, misdesigned probes, and batch effects. It can also help in detecting alternative splicing, start, or termination.
An Ancient Mitochondrial Polymorphism in Adalia bipunctata Linked to a Sex-Ratio-Distorting Bacterium
Authors: Jiggins Francis M , Tinsley Matthew C
Published: August 2005

Sex-ratio-distorting microbes are common parasites of arthropods. Although the reasons they have invaded and spread though populations are well understood, their subsequent dynamics within those populations are virtually unknown. We have found that different strains of a male-killing Rickettsia bacterium infecting the beetle Adalia bipunctata are associated with distinct mitochondrial haplotypes, which is expected as both the mitochondria and the bacteria are maternally transmitted. These mitochondrial haplotypes shared a common ancestor >2 million years ago, and their overall diversity is significantly greater than expected under neutrality from comparisons with a nuclear gene. Furthermore, a variety of statistical tests show strong deviations from neutrality in mitochondrial but not in nuclear genes. We therefore conclude that natural selection is probably maintaining a polymorphism of different Rickettsia strains in this species. Despite the age of the different mitochondrial haplotypes, there is very little genetic diversity within them. Furthermore, there is considerable variation in mitochondrial haplotype and bacterial strain frequency between populations, despite it being thought that this species has fairly low levels of population structure. We conclude that the fitness of these male killers may be negatively frequency dependent or different strains may be favored in different populations. These hypotheses await experimental confirmation.
Fate of Applied Sulfate in Volcanic Ash‐Influenced Forest Soils
Authors: Kimsey Mark , McDaniel Paul , Strawn Dan , Moore Jim
Published: August 2005

Forests in the Inland Northwest, USA, commonly show SO4 deficiency, suggesting limited SO4 availability in the soils. Regional soils, which lie between the east slopes of the northern Cascade Range and the west slopes of the northern Rocky Mountains, are influenced to varying degrees by poorly crystalline aluminosilicates and ferrihydrite, and are often classified as Andisols (Andosols). Research has shown that SO4 retention is greatly influenced by Fe and Al oxides. However, little is known of the sorption behavior exhibited by poorly crystalline andic soils of the region. In this study we investigated the mineralogy and SO4 sorption capacity of ash‐influenced soils found in the Inland Northwest. Batch SO4 adsorption experiments showed that up to 40% of added SO4 was adsorbed. Furthermore, there were positive correlations between soil SO4 adsorption capacity and increasing ash influence as measured by (i) the andic soil parameter %Alo + 0.5%Feo (R2 = 0.89), (ii) P retention (R2 = 0.91), and (iii) NaF pH (R2 = 0.48). Soil pH, total organic C (TOC), and percentage of clay showed insignificant or inconclusive relationships with SO4 adsorption. Release of adsorbed SO4 was significantly lower in volcanic ash‐influenced soils as compared with non‐ash soils, indicating a greater affinity for SO4 These results indicate that poorly crystalline aluminosilicates and Fe oxides significantly influence the amount of SO4 present in forest soil solutions. Successful nutrient management plans must recognize the sorption behavior of these andic soils.
Pharmaceuticals
Authors: Jiang Timothy T. , Acosta Daniel
Published: August 2005

This article provides a comprehensive summary of common adverse side effects associated with key pharmaceutical drugs used in the treatment of selected diseases and disorders. The focus of this chapter is on the use of drugs associated with key organs and physiological functions of the body. The main topics covered are Anesthetics, Analgesics, Sedative Hypnotics, Anti‐physchotic, Antiepileptics, Neurodegenerative Disorders, Adrenergic and Cholinergic Agents, Cardiovascular Drugs, and Hormone Antagonists.
Geneticists' views on science policy formation and public outreach
Authors: Mathews Debra J.H. , Kalfoglou Andrea , Hudson Kathy
Published: August 2005

Though much research about the public's views of scientists, genetic research and its moral, ethical, and social implications exists, little has been done to investigate how scientists view their own role(s) in public discussions and policy formation related to genetic research and technologies. We interviewed 20 academic geneticists in the United States about their perceptions of the roles they and others (e.g., professional societies, the public, ethicists, and elected officials) do and should play in the formation of science policy, the communication of science to the public, and the public discussions of moral and ethical issues raised by scientific advances. The participants in our study thought that scientists should be more actively involved in public outreach and science policy formation, but frequently they felt ill‐equipped and unsupported by their peers and institutions to pursue these activities. Furthermore, many were skeptical of or did not trust elected officials—who they consider uninformed about the issues and too driven by political agendas—to formulate sound science policy. They do, however, have faith in the ability of scientific societies to influence policy effectively, and some thought that societies should play a larger role, both in science policy and as a liaison between scientists and the public. Finally, participants offered suggestions for increasing the involvement and influence of scientists in science‐policy formation and public discourse. © 2005 Wiley‐Liss, Inc.