bluuebunny/crossref_metadata_2025 huggingface dataset:
Elemental Concentrations in Japanese Silicate Rock Standards JA‐1, JR‐1 and JB‐2
Authors: BOWER N.W. , GLADNEY E.S. , HAGAN R.C. , TRUJILLO P.E. , WARREN R.G.
Published: May 2007

Data on three Japanese geochemical reference samples (JR‐1, JA‐1, and JB‐2) are presented. Ten major and thirty‐five trace element concentrations were determined using x‐ray fluorescence, instrumental thermal neutron activation, thermal neutron capture prompt gamma‐ray spectrometry, delayed neutron assay, automated thermal neutron activation analysis, inductively coupled plasma emission, atomic absorption, and ion selective electrode. Good agreement between the various methods and with recent literature values were obtained using error weighted mean concentrations for the samples.
Additional Certified Values for CCRMP Soils SO‐1 to ‐4
Authors: STEGER H.F. , BOWMAN W.S. , McKEAGUE J.A.
Published: May 2007

New mean values for up to 11 major and minor and up to 11 trace elements in soils SO‐1 to SO4 have been calculated by two procedures. Analytical results received by CCRMP subsequent to the certification program of 1979 were included. In one instance, the same procedure as used for certification wherein all results except those rejected on chemical and/or statistical considerations was followed, but little improvement over the 1979 calculations was obtained. The other procedure is proposed by the authors for use in identifying concentration range intervals wherein maximum interlaboratory consensus is observed. The application of this procedure has permitted the certification of the four soils for the content of 24 elements not previously certified.
Reference Samples in Geology and Geochemistry
Authors: Flanagan F. J.
Published: May 2007

The report discusses some history of analytical problems that resulted in early standards. Geologic samples of economic interest and general information are discussed by country of origin, whereas geochemical samples are mentioned by samples types and by their intended use. Numerous topics and problems for reference samples and their data are discussed.
SPECTROPHOTOMETRIC DETERMINATION OF FERROUS IRON IN EIGHTEEN UNITED STATES GEOCHEMICAL REFERENCE STANDARDS
Authors: Bruce Charles B. , Bower Nathan W.
Published: May 2007

Iron (II) oxide in 50 mg samples of silicate rocks, deposits, and soils is measured after digestion with HF and HCl in the presence of ICl. The iodine produced is measured spectrophotometrically. Results are presented for the eighteen available USGS geochemical reference standards including the GXR series.
Determination of Gold in Twenty Geochemical Reference Samples by Flameless Atomic Absorption Spectrometry
Authors: BENEDETTI M.F. , KERSABIEC A.M. DE , BOULEGUE J.
Published: May 2007

After acid digestion, gold is extracted with MIBK and determinated by flameless atomic absorption spectrometry. The results for six USGS reference samples and fourteen French geochemical standards are presented and discussed. The agreement with working values for these standards is in the range of pm 5%.
Gold in BHVO‐1, BIR‐1, DNC‐1 and BCR‐1 by Fire‐Assay Preconcentration Neutron Activation Analysis: Sample Size vs. Accuracy
Authors: LOUIS Robert M. St.
Published: May 2007

Four mafic USGS rock standards (BHVO‐1, BIR‐1, DNC‐1, BCR‐1) were analyzed at three sample sizes (1, 5, and 10 g) for gold by neutron activation analysis subsequent to fire‐assay concentration. The results indicate that large samples, in the order of 10 g, are required to produce consistent results, although analyses of variance indicate that sample sizes of 5 g may be used effectively. The analysis of 1 g samples resulted in a large range of values and high standard deviations. BCR‐1 was found to be the most homogeneous of the four standards for gold, followed in decreasing order by BIR‐1, DNC‐1, and BHVO‐1. Data for Ir in BIR‐1 and DNC‐1 are also presented.
Compilation of Boron Concentration Data for NBS, USGS and CCRMP Reference Materials
Authors: GLADNEY Ernest S. , ROELANDTS Iwan
Published: May 2007

Boron concentration data on 69 different biological, coal and geological reference materials issued by NBS, USGS and CCRMP have been collected from 1951‐1986. Data from 135 journal articles and technical reports are included. These data are summarized in consensus (mean) values with uncertainties expressed as pm one standard deviation. Mean values are also calculated as a function of analytical procedure and all raw data are given in the tables.
Determination of Lead‐210, Radium‐226, Thorium‐228 and Uranium‐238 in Five CCRMP Reference Samples by Gamma‐Ray Spectrometry
Authors: Joshi S.R.
Published: May 2007

Lead‐210, radium‐226, thorium‐228 and uranium‐238 concentrations have been determined in five CCRMP reference samples using direct gamma‐ray spectrometry. Literature data are available for only lead‐210 and radium‐226 levels in these samples.
Determination of the Rare‐Earth Elements and Yttrium In 37 International Silicate Reference Materials By Inductively Coupled Plasma‐Atomic Emission Spectrometry
Authors: JARVIS Kym E. , JARVIS Ian
Published: May 2007

The rare‐earth elements (REE) and yttrium have been determined in 37 international rock and mineral reference materials. Samples were prepared using conventional rock‐dissolution techniques, and the REE and yttrium were separated from the other constituents using cation‐exchange chromatography. The REE (La, Ce, Pr, Nd, Sm, Eu, Gd, Dy, Ho, Er, Yb, Lu) and yttrium were determined simultaneously by inductively coupled plasma‐atomic emission spectrometry (ICP‐AES). Results for four well‐characterised USGS standard rocks agree favourably with “recommended” values and with REE determinations made previously by workers using ICP‐AES, isotope dilution mass spectrometry, instrumental neutron activaton analysis and X‐ray fluorescence spectrometry.

Les éléments de terres rares (TR) et yttrium ont été dosés dans 37 échantillons internationaux de réféence. Les échantillons ont été décomposés par dissolution acide et les TR séparés par résine échangeuse de cations. Les TR (La, Ce, Pr, Nd, Sm, Eu, Gd, Dy, Ho, Er, Yb, Lu) et yttrium ont été dosés simultanément par la spectrométrie d'émission‐plasma inductif. Les résultats obtenus pour quatre échantillons de référence bien charactérisés de I'USGS se comparent favorablement avec ceux obtenus par la spectrométrie d'émission‐plasma, la dilution isotopique, I'activation neutronique et par la spectrométrie d'é fluorescence‐X.
Boron Contents in Selected International Geochemical Reference Samples
Authors: LEEMAN William P.
Published: May 2007

Boron concentrations have been measured in fifteen geochemical reference materials using prompt gamma neutron activation analysis. Replicate analyses of these samples provide an indication of the precision of the method under “normal'’analytical conditions over an extended period of time.

La teneur en bore a été dosée dans quinze échantillons géochimiques de référence par l'activation neutronique avec “prompt gamma”. L'analyse répétée de ces échantillons démontre, en général, une bonne précision de la méthode en analyse de routine.
Robust Measures and the Estimator Limit
Authors: ABBEY Sydney
Published: May 2007

A new concept, the Estimator Limit, is proposed as a mean of overcoming discrepanices among the “robust'’measures used in deducing “best values'’from incoherent analytical data on proposed rock reference samples.

Un nouveau concept, l'“estimateur limite'’est proposé pour surmonter les inconsistances entre les mesures “robustes'’utilisées pour établir les “meilleures valeurs’à partir de données analytiques incohérentes (obtenues) sur des geostandards proposés.
The Determination of Major Oxide and Trace Element Concentrations in Eighteen Chinese Standard Reference Samples by X‐ray Fluorescence Spectrometry
Authors: VIVIT Davison V. , KING Bi‐Shia Wang
Published: May 2007

Eighteen Chinese geologic reference samples (stream sediments GSD 9–12, soils GSS 1–8, and rocks GSR 1–6) were analyzed by wavelength‐dispersive X‐ray fluorescence spectrometry (XRFS) for major elements Si, Ti, Al, Fe, Mn, Mg, Ca, Na, K, and P, and by energy‐dispersive XRFS for trace elements Ba, Ce, Cr, Cu, La, Nb, Ni, Rb, Sr, Y, Zn, and Zr. Major element analysis followed gravimetric determination of loss on ignition, and samples were prepared by fusion with Li2B4O7. A loose‐powder sample preparation was used for trace element analysis. The results reported in this study are, generally, in good agreement with concentrations compiled by X. Xie of the Geochemical Standard Reference Group and the Institute of Geophysical and Geochemical Exploration (People's Republic of China).
Determination of Trace Abundances of Ag, B, Ge, Mo, Sn, Tl and W in Geochemical Reference Samples by Atomic Emission Spectrography
Authors: KUZNETSOVA Albina I. , CHUMAKOVA Nina L.
Published: May 2007

Thirty‐one geochemical reference samples have been analysed for Ag, B, Ge, Mo, Sn, Tl and W by atomic emission spectrographic techniques with air‐jet controlled d.c. arc. The paper presents description of techniques and the data are compared to those from other studies.
Determination of the Rare Earth Elements in Thirteen GSJ Silicate Rock Reference Samples by Secondary Ion Mass Spectrometry
Authors: MacRAE N.D. , WU T‐W
Published: May 2007

Rare earth elements were determined by secondary ion mass spectrometry (SIMS) for 12 igneous rocks and one feldspar separate from the new rock reference samples of the Geological Survey of Japan. The study presents an expanded application of the SIMS facility.
Simultaneous Determination of Gallium and Molybdenum in Reference Materials Using Epithermal Activation Analysis and a Well‐Type Germanium Detector
Authors: LANDSBERGER S. , BODE P.
Published: May 2007

Ga and Mo were determined simultaneously with the use of a well‐type detector in routine epithermal neutron activation analysis. The interference of uranium has been evaluated. The data obtained on four reference samples are compared to published values.
Determination of Lithium in the NRCC Marine Sediments: MESS‐1, BCSS‐1, PACS‐1 and the NIST River Sediment: SRM 2704
Authors: RANTALA R.T.T. , LORING D.H.
Published: May 2007

NRCC marine sediment reference materials: MESS‐1, BCSS‐1, PACS‐1 and the NIST river sediment: SRM 2704 have been analyzed in replicate for lithium (Li) by flame atomic absorption spectrophotometry. Precision (% coefficient of variation) for the NRCC SRM's was <1.5%, and the NIST SRM was 4.3%. Results from replicate acid dissolution of the SRM's in Teflon bombs using boiling water and microwave heating showed no difference in Li concentration between the two methods.
On the Evaluation of Rock Reference Materials ‐A “Five‐Mode’ Approach*
Authors: ABBEY Sydney
Published: May 2007

The concentrations of numerous constituents must be evaluated in rock samples if they are to be used as reference materials. Because of varying degrees of specialized skills in earth‐science laboratories, the collaboration of many institutions is required in order to establish reliable values. Analytical data reported in such operations are highly variable. The number of constituents reported per sample varies from one laboratory to another. The number of values reported varies from one constituent to another. The reported values for each constituent are generally incoherent, often displaying skewed distributions. The problem is then how to deduce the most probably “true’ concentration for each constituent. Various computation schemes, based on medians, means and related measures, are discussed. A new scheme, involving a combination of modes, is proposed.
Determination of Platinum and Palladium in Sixty‐Eight Geochemical Reference Samples by Flameless Atomic Absorption Spectrometry
Authors: TERASHIMA Shigeru
Published: May 2007

Platinum and palladium contents of sixty‐eight geochemical reference samples have been determined by graphite furnace atomic absorption spectrometry after digestion of sample with aqua regia and hydrofluoric acid and extraction of platinum and palladium as iodides by methylisobutylketone (MIBK). The data are compared with those from other studies and crustal abundances.
Determination of Rare Earth Elements and Yttrium in Nine Geochemical Reference Samples Using a Novel Group Separation Procedure Involving Mixed‐Acid Elution Ion‐Exchange Chromatography
Authors: CROUDACE Ian W. , MARSHALL Stan
Published: May 2007

Rare earth data for nine well‐known geochemical reference samples were obtained using a rapid and efficient cation exchange chromatographic separation procedure. It involves the use of a mixed‐acid eluent (HCI and HNO3) on a 15 x 1 cm column of Bio‐Rad AG50–X8 (200–400 mesh) to remove matrix and many trace elements from rock solutions. The rare earth elements are removed from the column using 60 ml 7M HNO3. The pre‐concentration procedure described is routinely used in this laboratory for the determination of the rare earth elements by mass spectrometry‐isotope dilution, and has been satisfactorily used for their determination using inductively‐coupled plasma‐source atomic emission spectrometry.
Two New Polish Geological‐Environmental Reference Materials: Apatite Concentrate (CTA‐AC‐1) and Fine Fly Ash (CTA‐FFA‐1)
Authors: DYBCZYNASKI Rajmund , POLKOWSKA‐MOTRENKO Halina , SAMCZYNASKI Zbigniew , SZOPA Zygmunt
Published: May 2007

World‐wide intercomparison runs has made possible the certification of two new Polish geological‐environmental reference materials for multi‐element trace analysis: Apatite Concentrate (CTA‐AC‐1) and Fine Fly Ash (CTA‐FFA‐1). “Recommended values’ are established for 25 (CTA‐AC‐1) and 40 (CTA‐FFA‐1) elements respectively. In addition, “information values’ are assigned for 12 elements in CTA‐AC‐1 and 10 elements in CTA‐FFA‐1. Our method of data evaluation has been further improved and a modified version of criteria for assigning recommended and information values is proposed.
Spectrophotometric Determination of Zirconium in Thirty‐one Geochemical Reference Samples with Xylenol Orange
Authors: OKAI Takashi
Published: May 2007

The zirconium content of 31 geochemical reference samples has been determined by a spectrophotometric method with Xylenol orange after sample decomposition by acid digestion and alkali fusion. The agreement between the present results and published data is generally good.
What is A “Method”?
Authors: ABBEY Sydney
Published: May 2007

Using a recently published compilation of analytical data on reference samples SY‐2, SY‐3 and MRG‐1 as an example, a case is presented in favor of more precise terminology in describing analytical methods used in reporting data in collaborative programs. The technique of final measurement in a particular method is often less important than earlier operations, such as sample attack or technique of separation.
Determination of Silver in Seventy‐Three Geochemical Reference Samples by Atomic Absorption Spectrometry
Authors: Terashima Shigeru
Published: May 2007

The silver content of seventy‐three geochemical reference samples has been determined by atomic absorption spectrometry using an air‐acetylene flame or a graphite furnace atomizer, after extraction of silver as iodide with methyl isobutyl ketone (MIBK). A comparison with published data shows clearly the need for much more data on most reference samples.
ELEMENTAL CONCENTRATIONS IN TWENTY NIST STANDARDS OF GEOCHEMICAL INTEREST
Authors: BOWER N.W. , LEWIS C.M. , NEIFERT P.E. , GLADNEY E.S.
Published: May 2007

Data are presented for twenty standard reference materials currently available from the USA's National Institute of Standards and Technology (NIST) that are of use in geochemical analyses. Some of these standards have not been previously presented in the geochemical literature and many elements’concentrations are reported here for the first time. Instrumental neutron activation analysis, X‐ray fluorescence, colorimetry, and coulometry were employed to obtain results on ten major and thirty‐eight trace element concentrations as well as H2O+ and H2O‐. Error bars for the analyses as well as consensus values from the literature are presented and generally good agreement are obtained for the available values.
DETERMINATION OF FLUORINE, CHLORINE, BROMINE AND IODINE IN SEVEN GEOCHEMICAL REFERENCE SAMPLES
Authors: LANGENAUER Marcel , KRÄHENBÜHL Urs , FURRER Verena , WYTTENBACH Armin
Published: May 2007

The concentrations of fluorine, chlorine, bromine and iodine of seven geochemical reference samples have been determined. Analytical techniques were neutron activation analysis for chlorine, bromine and iodine and ion‐selective potentiometry for fluorine. After irradiation of the samples, these halogens were separated from the matrix elements by pyrohydrolysis in presence of vanadium (V) oxide. This extraction allows to measure the four halogens in the same sample.
1988 COMPILATION OF ELEMENTAL CONCENTRATION DATA FOR USGS AGV‐1, GSP‐1 AND G‐2
Authors: GLADNEY Ernest S. , JONES Elizabeth A. , NICKELL Eric J. , ROELANDTS Iwan
Published: May 2007

Concentration data on up to 90 individual constituents in USGS AGV‐1, GSP‐1, and G‐2 have been collected from 1270 journal articles and technical reports. These data are summarized in consensus (mean) values with uncertainties expressed as +/‐ one standard deviation. Mean values are also calculated as a function of analytical procedure and all raw data are given in the tables. Recommended values are proposed based upon data criteria used by NIST (National Institute of Standards and Technology, formerly the National Bureau of Standards or NBS).
APPLICATION OF THE ICP‐MS TECHNIQUE TO TRACE ELEMENT ANALYSIS OF PERIDOTITES AND THEIR MINERALS
Authors: IONOV D.A. , SAVOYANT L. , DUPUY C.
Published: May 2007

Inductively coupled plasma mass spectrometry (ICP‐MS) has been applied to the determination of Rb, Sr, Ba, Zr, Hf, Nb, Ta, Th, U, Pb, Sc and 14 REE in peridotites and their constituent minerals: garnet, clinopyroxene, orthopyroxene and olivine. Determination limits for most elements are 1–10 ppb (in the solid sample), with accuracy and precision comparable to those of thermal ionisation and spark‐source mass spectrometry. New data on international standards PCC‐1, DTS‐1, UB‐N and JP‐1 are reported.
TERMINOLOGY FOR GEOLOGICAL REFERENCE MATERIAL VALUES: A PROPOSAL TO THE INTERNATIONAL ORGANISATION FOR STANDARDISATION (ISO), PRODUCERS AND USERS
Authors: POTTS Philip J. , KANE Jean S.
Published: May 2007

A new terminology is proposed for categorising values in geological reference materials based on the confidence that may be placed in an individual datum. This classification scheme is designed to be applicable to data derived from both cooperative analysis programmes and compilations of data published in the literature. Use of the following terminology is proposed: “certified value equivalent”, “recommended value” and “provisional value”, depending on the associated one sigma confidence limits and other analytical criteria listed in Table 1. To demonstrate the application to data that was originally assessed using different criteria and terminology, the proposed scheme has been used to reclassify data derived from the cooperative analysis program for USGS SDO‐1 (Devonian Shale) and a compilation of published data for USGS G‐1 (granite).
RARE EARTH ELEMENT CONCENTRATIONS IN USGS AND CCRMP IGNEOUS ROCK STANDARDS DETERMINED BY HIGH PERFORMANCE ION CHROMATOGRAPHY
Authors: WATKINS Ronald T. , le ROEX Anton P.
Published: May 2007

Eleven rare earth elements (REE) have been determined in ten USGS and two CCRMP igneous rock standards using high performance ion chromatography. Duplicate analyses of two or more separately prepared aliquots of each sample were undertaken; reproducibility was better than 5% for each of the REE. In most cases, the results compare closely with published REE values for those samples for which the REE are well characterised. Where the results for individual elements are in disagreement with published data, the more erratic patterns yielded by the earlier data when plotted on chondrite‐normalised REE diagrams suggest that values determined in this study are of greater accuracy.
XRF AND INAA DETERMINATIONS OF MAJOR AND TRACE ELEMENTS IN GEOLOGICAL SURVEY OF JAPAN IGNEOUS AND SEDIMENTARY ROCK STANDARDS
Authors: HALLETT R. Bruce , KYLE Philip R.
Published: May 2007

Major and trace element analyses have been obtained by wavelength dispersive X‐ray fluorescence for the Geological Survey of Japan Igneous rock series and selected samples from the Sedimentary rock series reference samples. Additional trace element data for the Igneous rock series were obtained by instrumental neutron activation analysis. Samples were analyzed multiple times for 10 major elements (with loss‐on‐ignition) and the following trace elements; As, Ba, Ce, Co, Cr, Cs, Cu, Eu, Ga, Hf, La, Lu, Nb, Nd, Ni, Pb, Rb, Sb, Sc, Sm, Sr, Ta, Tb, Th, U, V, W, Y, Yb, Zn and Zr.
THE PREPARATION AND CERTIFICATION OF FOURTEEN SOUTH AFRICAN SILICATE ROCKS FOR USE AS REFERENCE MATERIALS*
Authors: RING Edward Joseph
Published: May 2007

This report describes the preparation, analysis and certification of South African Reference Materials (SARMs) 39 to 52. These materials, which comprise a suite of rock materials originally named SAROCs, were collected from many locations within the Republic of South Africa. Nineteen laboratories in five countries used a variety of analytical techniques to provide the analytical results. The certified and tentative values that have been assigned to a number of constituents are presented in tabular form in appendices.
FLUORINE ABUNDANCES OF TWENTY NINE GEOLOGICAL AND OTHER REFERENCE SAMPLES USING FAST‐NEUTRON ACTIVATION ANALYSIS
Authors: CROUDACE Ian W. , RANDLE Keith
Published: May 2007

The fluorine content in twenty‐nine reference samples of geological interest has been determined using a well tried and tested method which has been previously reported. The analytical method uses fast neutron activation involving the reaction 19F(n,a)16N and gamma spectrometry. Interferences have been found to be negligible for the experimental conditions used. The method involves minimal sample preparation, is rapid and can easily measure concentrations down to 5 parts per million in a 5 g sample.
DETERMINATION OF ALL PLATINUM GROUP ELEMENTS IN SIX NEW CHINESE PGE GEOCHEMICAL STANDARD REFERENCE SAMPLES USING NEUTRON ACTIVATION ANALYSIS AFTER A NICKEL SULPHIDE FIRE ASSAY PRECONCENTRATION
Authors: Xiaolin LI , Chunhan TONG
Published: May 2007

Six new Chinese PGE geochemical standard reference samples, GPt‐1 to GPt‐6, were analyzed by neutron activation analysis after nickel sulphide fire assay preconcentration. Analytical data on all platinum group elements are presented along with a brief description of the analytical procedure.
MAJOR AND TRACE ELEMENT DETERMINATIONS ON NIST GLASS STANDARD REFERENCE MATERIALS 611, 612, 614 AND 1834 BY INDUCTIVELY COUPLED PLASMA‐MASS SPECTROMETRY
Authors: HOLLOCHER Kurt , RUIZ Joaquin
Published: May 2007

We report on the major and trace element composition and homogeneity of NIST (National Institute of Standards and Technology) glass standard reference materials 611, 612, 614, and 1834 for use as microanalytical trace element standards in laser ablation‐inductively coupled plasma‐mass spectrometry. The four analyzed NIST glasses were not designed as microanalytical standards, but their availability and careful preparation made them obvious candidates. Our data indicate that NIST 1834 is inhomogeneous on a scale of 100 mg with respect to several trace elements. Within analytical uncertainty, NIST 611, 612, and 614 are apparently homogeneous.
NEW TRACE ELEMENT AND REE DATA IN THIRTEEN GSF REFERENCE SAMPLES BY ICP‐MS
Authors: BALARAM V. , RAMESH S.L. , ANJAIAH K.V.
Published: May 2007

Analytical data on 34 geochemically significant trace elements (Sc, V, Cr, Co, Ni, Cu, Zn, Ga, Rb, Sr, Y, Zr, Nb, Cs, Ba, Hf, Ta, Pb, The, U and REE) by using Inductively Coupled Plasma Mass Spectrometry (ICP‐MS), for 13 reference rock samples obtained from the Geological Survey of Finland are presented. For many elements, especially most of the heavy‐REE, concentrations are reported here for the first time.
MAJOR AND TRACE ELEMENT ANALYSIS OF FIFTEEN JAPANESE IGNEOUS REFERENCE ROCKS BY XRFS AND INAA
Authors: STIX John , GORTON Michael P. , FONTAINE Eric
Published: May 2007

Fifteen Japanese igneous reference rocks have been analyzed by X‐ray fluorescence spectrometry and instrumental neutron activation analysis for major and trace elements. Agreement between measured and accepted values is generally favourable with, however, several exceptions. Small systematic discrepancies are noted for MgO, Na2O, Sr, The, Eu, and Lu, which are likely the result of differences in calibration and/or analytical techniques. Zn generally shows poor agreement, suggesting that the rocks are not well characterized for this element.
Design For Existing Lines: Part and Process Plan Optimization to Best Utilize Existing Production Lines
Authors: Smithson Arlene G. , Hamza Karim , Saitou Kazuhiro
Published: May 2007

This paper presents a method for modifying the design of the new part for the maximum utilization of existing production lines dedicated to other products. The method takes as inputs a nominal part design and the process information of the (potentially multiple) existing line(s), and produces a modified part design and a process sequence of the new part that maximizes the utilization of available manufacturing processes in the existing lines or equivalently minimizes the addition of new processes dedicated to the new product. The problem is formulated as mixed discrete-continuous multiobjective optimization. A multiobjective genetic algorithm is used to generate Pareto optimal designs for the optimization analysis. A case study on the production of a new machine bracket considering two available production lines is presented.
Large-Scale Spatial-Transmission Models of Infectious Disease
Authors: Riley Steven
Published: May 2007

During transmission of seasonal endemic diseases such as measles and influenza, spatial waves of infection have been observed between large distant populations. Also, during the initial stages of an outbreak of a new or reemerging pathogen, disease incidence tends to occur in spatial clusters, which makes containment possible if you can predict the subsequent spread of disease. Spatial models are being used with increasing frequency to help characterize these large-scale patterns and to evaluate the impact of interventions. Here, I review several recent studies on four diseases that show the benefits of different methodologies: measles (patch models), foot-and-mouth disease (distance-transmission models), pandemic influenza (multigroup models), and smallpox (network models). This review highlights the importance of the household in spatial studies of human diseases, such as smallpox and influenza. It also demonstrates the need to develop a simple model of household demographics, so that these large-scale models can be extended to the investigation of long–time scale human pathogens, such as tuberculosis and HIV.
Mars: A New Core-Crystallization Regime
Authors: Stewart Andrew J. , Schmidt Max W. , van Westrenen Wim , Liebske Christian
Published: May 2007

The evolution of the martian core is widely assumed to mirror the characteristics observed for Earth's core. Data from experiments performed on iron-sulfur and iron-nickel-sulfur systems at pressures corresponding to the center of Mars indicate that its core is presently completely liquid and that it will not form an outwardly crystallizing iron-rich inner core, as does Earth. Instead, planetary cooling will lead to core crystallization following either a “snowing-core” model, whereby iron-rich solids nucleate in the outer portions of the core and sink toward the center, or a “sulfide inner-core” model, where an iron-sulfide phase crystallizes to form a solid inner core.
Because Science Matters
Authors: Pope Barbara Kline
Published: May 2007

A Scientist's Guide to Talking with the Media
. Practical Advice from the Union of Concerned Scientists.
By Richard Hayes and Daniel Grossman
. Rutgers University Press, New Brunswick, NJ, 2006. 228 pp. Paper, $18.95. ISBN 9780813538587.

Hayes and Grossman offer researchers advice on how to work with the media to best present their findings and advice to a broad, public audience.
In-House Growth-Promoting Transport System for
Neisseria gonorrhoeae
Authors: Sharma Dharmendra , Sethi Sunil , Mehta Swami Das , Sharma Meera
Published: May 2007

Eno powder (GlaxoSmithKline), an antacid preparation readily available over the counter, was used instead of a CO
2
generator for the growth of 15 strains of
Neisseria gonorrhoeae
obtained from men with urethritis. Due to its easy accessibility and low cost, Eno powder can be useful in developing countries for transporting clinical specimens from resource-poor peripheral labs to reference laboratories.
Abilities of APTIMA, AMPLICOR, and ProbeTec Assays To Detect
Chlamydia trachomatis
and
Neisseria gonorrhoeae
in PreservCyt ThinPrep Liquid-Based Pap Samples
Authors: Chernesky M. , Jang D. , Portillo E. , Chong S. , Smieja M. , Luinstra K. , Petrich A. , MacRitchie C. , Ewert R. , Hayhoe B. , Sarabia A. , Thompson F.
Published: May 2007

Infections with
Chlamydia trachomatis
and
Neisseria gonorrhoeae
are often asymptomatic. Liquid-based Pap (L-Pap) screening may provide samples for testing by commercial assays. Women attending a health clinic or a street youth clinic had a PreservCyt ThinPrep sample and a cervical swab (CS) collected. The L-Pap sample was tested for cytopathology; then 1 ml was transferred to an L-Pap specimen transfer tube for testing by the Gen-Probe APTIMA assays (APTIMA Combo 2 [AC2], APTIMA
C. trachomatis
[ACT], and APTIMA
N. gonorrhoeae
[AGC]). The residual L-Pap sample was tested for
C. trachomatis
and
N. gonorrhoeae
using Roche AMPLICOR (AMP) and Becton Dickinson ProbeTec (PT). The CS was tested by AC2. A patient was considered infected if two specimens were positive or if a single specimen was positive in two tests. The prevalence of infection was 10% (29/290) for
C. trachomatis
and 2.4% (7/290) for
N. gonorrhoeae
. Most of the positive patients had specimens that were reactive in all assays (20/29 for
C. trachomatis
; 6/7 for
N. gonorrhoeae
). Four patients had double infections. The sensitivities and specificities of the various tests for the specimens tested were as follows. For
C. trachomatis
on L-Pap, sensitivity and specificity were 100 and 98.1%, respectively, for ACT, 93.1 and 98.8% for AC2, 86.2 and 91.2% for AMP, and 72.4 and 92.7% for PT. For
N. gonorrhoeae
on L-Pap, sensitivity and specificity were 100% for both AGC and AC2, 85.7 and 100% for AMP, and 85.7 and 100% for PT. For AC2 with CSs, sensitivity and specificity were 93.1 and 98.5%, respectively, for
C. trachomatis
, and both were 100% for
N. gonorrhoeae
. There were significant differences in sensitivity and specificity (
P
< 0.001). The APTIMA assays were more sensitive and specific than AMP or PT for detecting women's
C. trachomatis
and/or
N. gonorrhoeae
infections by testing ThinPrep samples.
Transmission of
Enterocytozoon bieneusi
between a Child and Guinea Pigs
Authors: Cama Vitaliano A. , Pearson Julie , Cabrera Lilia , Pacheco Luz , Gilman Robert , Meyer Sarah , Ortega Ynes , Xiao Lihua
Published: May 2007

An unusual
Enterocytozoon bieneusi
genotype was found in seven guinea pigs and a 2-year-old child in the same household. The genetic uniqueness of the parasite, its wide occurrence in other guinea pigs in the community, and its absence in other children in the community suggest the possibility of zoonotic transmission of the infection to the study child.
Antibody Binding in Proximity to the Receptor/Glycoprotein Complex Leads to a Basal Level of Virus Neutralization
Authors: Yang Xinzhen , Lipchina Inna , Lifton Michelle , Wang Liping , Sodroski Joseph
Published: May 2007

Hypothetically, antibodies may neutralize enveloped viruses by diverse mechanisms, such as disruption of receptor binding, interference with conformational changes required for virus entry, steric hindrance, or virus aggregation. Here, we demonstrate that retroviral infection mediated by the avian sarcoma-leukosis virus (ASLV-A) envelope glycoproteins can be neutralized by an antibody directed against a functionally unimportant component of a chimeric receptor protein. Thus, the binding of an antibody in proximity to the retroviral envelope glycoprotein-receptor complex, without binding to the entry machinery itself, results in neutralization. This finding provides additional support for the hypothesis that steric hindrance is sufficient for antibody-mediated neutralization of retroviruses.
Mn
2+
Suppressor Mutations and Biochemical Communication between Ty1 Reverse Transcriptase and RNase H Domains
Authors: Yarrington Robert M. , Chen Jichao , Bolton Eric C. , Boeke Jef D.
Published: May 2007

Ty1 reverse transcriptase/RNase H (RT/RH) is exquisitely sensitive to manganese concentrations. Elevated intracellular free Mn
2+
inhibits Ty1 retrotransposition and in vitro Ty1 RT-polymerizing activity. Furthermore, Mn
2+
inhibition is not limited to the Ty1 RT, as this ion similarly inhibits the activities of both avian myeloblastosis virus and human immunodeficiency virus type 1 RTs. To further characterize Mn
2+
inhibition, we generated RT/RH suppressor mutants capable of increased Ty1 transposition in
pmr1
Δ cells.
PMR1
codes for a P-type ATPase that regulates intracellular calcium and manganese ion homeostasis, and
pmr1
mutants accumulate elevated intracellular manganese levels and display 100-fold less transposition than
PMR1
+
cells. Mapping of these suppressor mutations revealed, surprisingly, that suppressor point mutations localize not to the RT itself but to the RH domain of the protein. Furthermore, Mn
2+
inhibition of in vitro RT activity is greatly reduced in all the suppressor mutants, whereas RH activity and cleavage specificity remain largely unchanged. These intriguing results reveal that the effect of these suppressor mutations is transmitted to the polymerase domain and suggest biochemical communication between these two domains during reverse transcription.
Characterization of Rift Valley Fever Virus Transcriptional Terminations
Authors: Ikegami Tetsuro , Won Sungyong , Peters C. J. , Makino Shinji
Published: May 2007

Rift Valley fever virus (RVFV) (genus
Phlebovirus
, family
Bunyaviridae
) has a tripartite negative-strand genome and causes a mosquito-borne disease among humans and livestock in sub-Saharan African and Arabian Peninsula countries. Phlebovirus L, M, and N mRNAs are synthesized from the virus-sense RNA segments, while NSs mRNA is transcribed from the anti-virus-sense S segment. The present study determined the 3′ termini of all RVFV mRNAs. The 3′ termini of N and NSs mRNAs were mapped within the S-segment intergenic region and were complementary to each other by 30 to 60 nucleotides. The termini of M and L mRNAs were mapped within 122 to 107 nucleotides and 16 to 41 nucleotides, respectively, from the 5′ ends of their templates. Viral RNA elements that control phlebovirus transcriptional terminations are largely unknown. Our studies suggested the importance of a pentanucleotide sequence, CGUCG, for N, NSs, and M mRNA transcription terminations. Homopolymeric tracts of C sequences, which were located upstream of the pentanucleotide sequence, promoted N and M mRNA terminations. Likewise, the homopolymeric tracts of G sequences that are found upstream of the pentanucleotide sequence promoted NSs mRNA termination. The L-segment 5′-untranslated region (L-5′ UTR) had neither the pentanucleotide sequence nor homopolymeric sequences, yet replacement of the S-segment intergenic region with the L-5′ UTR exerted N mRNA termination in an infectious virus. The L-5′ UTR contained two 13-nucleotide-long complete complementary sequences, and their sequence complementarities were important for L mRNA termination. A computer-mediated RNA secondary structure analysis further suggested that RNA secondary structures formed by the sections of the two 13-nucleotide-long sequences and by the sequence between them may have a role in L mRNA termination. Our data demonstrated that viral RNA elements that govern L mRNA termination differed from those that regulate mRNA terminations in the M and S segments.
Linkage maps for Arabidopsis lyrata subsp. lyrata andArabidopsis lyratasubsp. petraea combining anonymous and Arabidopsis thaliana–derived markers
Authors: Beaulieu Julien , Jean Martine , Belzile François
Published: May 2007

Arabidopsis lyrata, a close relative of the model plant Arabidopsis thaliana, is 1 of a few plant species for which the genome is to be entirely sequenced, which promises to yield important insights into genome evolution. Only 2 sparse linkage maps have been published, and these were based solely on markers derived from the A. thaliana genome. Because the genome of A. lyrata is practically twice as large as that of A. thaliana, the extent of map coverage of the A. lyrata genome remains uncertain. In this study, a 2-way pseudo-testcross strategy was used to construct genetic linkage maps of A. lyrata subsp. petraea and A. lyrata subsp. lyrata, using simple sequence repeat (SSR) and cleaved amplified polymorphic sequence (CAPS) markers from the A. thaliana genome, and anonymous amplified fragment length polymorphism (AFLP) markers that could potentially uncover regions unique to the A. lyrata genome. The SSR and CAPS markers largely confirmed the relationships between linkage groups in A. lyrata and A. thaliana. AFLP markers slightly increased the coverage of the A. lyrata maps, but mostly increased marker density on the linkage groups. We noted a much lower level of polymorphism and a greater segregation distortion in A. lyrata subsp. lyrata markers. The implications of these findings for the sequencing of the A. lyrata genome are discussed.
Genetic maps of the proximal half of chromosome arm 2L of Drosophila melanogaster
Authors: Levine Sylvia Glen , Sunday Suchot , Dörig Ruth E. , Suter Beat , Lasko Paul
Published: May 2007

Drosophila mutants have played an important role in elucidating the physiologic function of genes. Large-scale projects have succeeded in producing mutations in a large proportion of Drosophila genes. Many mutant fly lines have also been produced through the efforts of individual laboratories over the past century. In an effort to make some of these mutants more useful to the research community, we systematically mapped a large number of mutations affecting genes in the proximal half of chromosome arm 2L to more precisely defined regions, defined by deficiency intervals, and, when possible, by individual complementation groups. To further analyze regions 36 and 39–40, we produced 11 new deficiencies with gamma irradiation, and we constructed 6 new deficiencies in region 30–33, using the DrosDel system. trans-heterozygous combinations of deficiencies revealed 5 additional functions, essential for viability or fertility.
Wide range QTL analysis for complex architectural traits in a 1-year-old apple progeny
Authors: Segura V. , Denancé C. , Durel C.-E. , Costes E.
Published: May 2007

The present study aimed at investigating the genetic determinisms of architectural traits in a 1-year-old apple ( Malus × domestica Borkh.). F1progeny. A precise phenotyping including both tree topology and geometry was performed on 123 offspring. For a wide range of developmental traits, broad-sense heritability was estimated and quantitative trait loci (QTLs) were investigated. Several loci controlling geometry were identified (i) for integrated traits, such as tree surface and volume; (ii) for traits related to the form of long sylleptic axillary shoots (LSAS), such as bending and basis angle; and (iii) for traits of finer components, such as internode length of the trunk and LSAS. Considering topology, 4 QTLs were mapped for the total number of sylleptic branching in the tree, suggesting a strong and complex genetic control that was analysed through colocalisations between QTLs mapped for the different shoot types (long, medium, short). Two QTLs were also mapped for a phenological trait (date of bud break). When several QTLs were detected for a trait, a linear model was built to test epistatic effects and estimate the whole percentage of variability explained. The discussion focuses on particular colocalisations and on the relevance of traits to further tree development.
Characteristics of controlled low-strength materials incorporating cement kiln dust
Authors: Lachemi M , Hossain K M.A , Shehata M , Thaha W
Published: May 2007

This paper presents a study that focuses on evaluating the feasibility of incorporating cement kiln dust (CKD) in the development of controlled low-strength materials (CLSM). A preliminary study (phase I) was conducted (based on fresh and strength properties) to understand the behaviour of 12 selected CLSM mixtures where CKD and cement content varied from 4% to 45% and from 2% to 4% of total mass, respectively. Subsequently, four best CLSM mixes were selected for a detailed study (phase II), which investigated fresh and hardened properties, addressed durability issues, and made recommendations for suitable mix designs for field applications. The research suggests that CLSM with acceptable properties can be developed using moderate volumes of CKD (up to 15% by mass). A combination of 2% cement and 10% CKD or 15% CKD and no cement can provide a mix that satisfies the requirements of a CLSM. Sustainable development in the cement industry can be partly achieved by producing CKD-based CLSM, as it consumes cogenerated products from the cement manufacturing process.Key words: cement kiln dust, controlled low-strength material, mix design, fresh–mechanical properties, durability.
Optimization of municipal wastewater biological nutrient removal using ASM2d
Authors: Kennedy Kevin J , McHarg Amy Marie
Published: May 2007

Activated sludge model No. 2d (ASM2d) was calibrated then used to determine optimal recycle rates and basin retention times, with respect to final N, soluble P (sP) or N plus sP concentrations for Modified Bardenpho (MB), Modified University of Cape Town (MUCT), and anaerobic–anoxic–oxic (A2O) biological nutrient removal processes. Simulations were conducted at two temperatures and three primary effluent (PE) concentrations (COD, TSS, TKN, sP). All BNR processes were shown to be capable of achieving an effluent sP concentration below 1 mg/L at all conditions when effluent N concentration was neglected. None of the processes were capable of producing an effluent with N concentrations below 5 mg/L at high PE concentration. The MB and MUCT processes were both successful in achieving a combined sP and N removal below 1 mg/L and 5 mg/L for low PE concentrations at 10 and 20 ºC. Only the MB process, at 20 ºC with medium PE concentrations, was found to achieve an effluent below 1 mg/L and 5 mg/L, respectively for sP and N. Recycle from the anoxic basin of the MUCT process had an insignificant effect on N and sP removals. All input variables to the MB and A2O process proved to be somewhat significant and it is recommended that they be kept within future experimental designs. Dynamic tests with real Ottawa plant influent flow data indicated that the MB process was more robust with respect to TN, sP, and CBOD5 removal than the MUCT process.Key words: activated sludge, biological nutrient removal, simulation, model, ASM2d.
Selection of water treatment processes using Bayesian decision network analyses
Authors: Zhu Zoe J.Y. , McBean Edward A
Published: May 2007

Decisions on selection between alternative water treatment sequences require numerous considerations, including treatment effectiveness and costs of the individual technologies, water quality guidelines, and the characteristics of the influent source water. Bayesian decision networks (BDNs) are demonstrated to provide a normative framework to assist in decision making for problem domains where tradeoffs are needed between uncertainty in the domain and the preferences of decision makers. A methodology is developed to apply BDNs and the methodology, and is illustrated with experimental results.Key words: Bayesian decision network, uncertainty, risk assessment, water quality, water treatment processes.
Occurrence of N-nitrosamines in Alberta public drinking-water distribution systems
Authors: Charrois Jeffrey W.A. , Boyd Jessica M , Froese Kenneth L , Hrudey Steve E
Published: May 2007

Since the 1974 discovery of trihalomethanes as disinfection by-products (DBPs) in drinking water, the regulatory and public health focus has been primarily directed at halogenated compounds, even though it is well established that chlorination and chloramination also produce non-halogenated DBPs. Specific halogenated DBPs that could reasonably explain the correlation of some adverse health outcomes with consumption of disinfected drinking water in a number of epidemiologic studies have yet to be identified. We therefore explored an emerging class of non-halogenated DBPs, N-nitrosamines, which warrant consideration given public health concerns regarding possible correlations of bladder cancer with exposure to chlorinated drinking water. We developed a dual media (Ambersorb® 572 and LiChrolut® EN), off-line, solid-phase extraction method that utilized a modified commercially-available extraction manifold combined with our previous GC–MS ammonia positive chemical ionization (PCI) quantitative method for analyzing N-nitrosamines in drinking water. We surveyed 20 Alberta municipal drinking-water distribution systems for the presence of N-nitrosodimethylamine (NDMA) and seven other N-nitrosamine species. Analytical results revealed the occurrence of NDMA (up to 100 ng/L) as well as two other N-nitrosamines (N-nitrosopyrrolidine and N-nitrosomorpholine) within select Alberta drinking water supplies.Key words: Alberta, chloramination, disinfection by-products, distribution system, drinking water, N-nitrosamines, NDMA, public health, survey.
Prediction of flow rates for potable water supply from directionally drilled horizontal wells in river sediments
Authors: Birch S , Donahue R , Biggar K W , Sego D C
Published: May 2007

Horizontal wells installed by directional drilling in the highly permeable river bottom sediments can improve the quality of water delivered to water treatments plants by filtration of suspended solids and dilution with groundwater. Predicting the flow rates available from horizontal wells is an important step in evaluating the technology. A series of three-dimensional finite element models were developed to simulate a horizontal well located beneath a river and a parametric analysis of predicted flow as a function of pipe length, pipe diameter, depth below river bottom, and sediment hydraulic conductivity was conducted to determine optimum horizontal well configurations. The results indicated that the frictional head losses in the well screen have a significant impact on predicted withdrawal rates. Analysis of well length and pipe diameter indicates that for each specific well configuration there exists an optimum length, beyond which little increase in flow occurs. The simulations indicated maximum flows occur when horizontal wells are placed as deep as possible until they are within 0.5 to 2.5 m of an impermeable lower boundary.Key words: directional drilling, water supply, horizontal wells, river filtration.