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Introduction Advanced Clinical Practice (ACP) roles are increasingly being developed internationally. Identifying factors perceived as affecting the development of ACP can support effective implementation. Aim To understand the views of senior health service staff as to factors influencing the development of ACP roles in mental health services. Method Focus group and semi structured interviews. Participants were directors of nursing (n = 10) and other senior staff from roles important to workforce development (n =10). Results Content analysis suggested 7 categories: understanding the role and national guidelines, attitudes to the role, learning from implementing other roles, understanding pre-requisites for development, challenges, opportunities, and future support/actions.. Prerequisites for success would include early engagement with stakeholders. Medical attitudes towards ACP roles were perceived as generally more positive than previously. Discussion The study provides unique information regarding perspectives of senior staff regarding the implementation of ACP roles in mental health services. A wide range of mental health services were perceived as potentially benefiting from ACPs, with the importance of role clarity being highlighted and long-term developmental pathways for staff. Implications for practice Successful Implementation of ACP roles may require clear role definition, early engagement with stakeholders and processes to evaluate role outcomes. Accessible summary What is known on the subject? • Advanced Clinical Practitioners (ACPs) are, typically, non-medical healthcare professionals, who possess advanced clinical skills, a master’s level qualification and evidence of leadership, management and research abilities. • Most ACPs are nurses and new ACP roles are increasingly being established around the world. • The views of senior staff towards new mental health nursing roles in organisations is likely to influence their introduction and sustainability • Research on mental health nursing ACP roles is sparse. What the paper adds to existing knowledge • The paper uniquely provides specific information as to factors perceived by senior staff as affecting the implementation of ACP roles in mental health services. • A wide range of mental health services were perceived as potentially benefiting from ACPs • Establishing role clarity for MHN ACPs is perceived as being as essential to successful introduction of the role, as has been found for other specialities What are the implications for practice? • Participants identified a need for early engagement with service users and professions about new ACP roles and for processes that can evaluate ACP roles once they established. • Some mental health nurses may require long-term developmental pathways to help prepare them to take on a master’s level course and then the ACP role.

The objective of this study is to investigate the role of segments, rhythm, and rhythm combined with intonation in the identification of a speaker's dialect. In a between-subjects design using three conditions, we tested 62 listeners (Zurich Swiss German) in a two-alternative-forced choice dialect identification experiment: in condition one, 21 listeners were asked to identify two dialects (Valais and Bern Swiss German) in unmorphed form. In condition two, 20 different listeners had to identify the same two dialects but with swapped speech rhythm, and in condition three, 21 different listeners had to identify the same dialects with swapped speech rhythm and intonation. The experiment showed that exchanging speech rhythm alone or speech rhythm combined with intonation had very little effect on the listeners’ dialect identification performance: listeners appear to use primarily segmental information in the identification process. Further results revealed that (a) superimposing the prosodic structure of one dialect (Bern Swiss German) onto another (Valais Swiss German) caused greater variability across some listeners than the other way around and that (b) identification performance varies as a function of sentence material used, i.e. how the sentences differ in segmental and prosodic make-up. We discuss implications for forensic phonetics, language and cognition, and automatic speech recognition.

CRISPR–Cas systems eliminate nucleic acid invaders in bacteria and archaea. The effector complex of the Type III-B Cmr system cleaves invader RNAs recognized by the CRISPR RNA (crRNA ) of the complex. Here we show that invader RNAs also activate the Cmr complex to cleave DNA. As has been observed for other Type III systems, Cmr eliminates plasmid invaders in Pyrococcus furiosus by a mechanism that depends on transcription of the crRNA target sequence within the plasmid. Notably, we found that the target RNA per se induces DNA cleavage by the Cmr complex in vitro. DNA cleavage activity does not depend on cleavage of the target RNA but notably does require the presence of a short sequence adjacent to the target sequence within the activating target RNA (rPAM [RNA protospacer-adjacent motif]). The activated complex does not require a target sequence (or a PAM) in the DNA substrate. Plasmid elimination by the P. furiosus Cmr system also does not require the Csx1 (CRISPR-associated Rossman fold [CARF] superfamily) protein. Plasmid silencing depends on the HD nuclease and Palm domains of the Cmr2 (Cas10 superfamily) protein. The results establish the Cmr complex as a novel DNA nuclease activated by invader RNAs containing a crRNA target sequence and a rPAM.

Gaseous and particulate pollutant concentrations associated with five samples per day collected during a July 2001 summer intensive study at the Pittsburgh Carnegie Mellon University (CMU) Supersite were used to apportion fine particulate matter (PM2.5) into primary and secondary contributions using PMF2. Input to the PMF2 analysis included the concentrations of PM2.5 nonvolatile and semivolatile organic material, elemental carbon (EC), ammonium sulfate, trace element components, gas-phase organic material, and NO(x), NO2, and O3 concentrations. A total of 10 factors were identified. These factors are associated with emissions from various sources and facilities including crustal material, gasoline combustion, diesel combustion, and three nearby sources high in trace metals. In addition, four secondary sources were identified, three of which were associated with secondary products of local emissions and were dominated by organic material and one of which was dominated by secondary ammonium sulfate transported to the CMU site from the west and southwest. The three largest contributors to PM2.5 were secondary transported material (dominated by ammonium sulfate) from the west and southwest (49%), secondary material formed during midday photochemical processes (24%), and gasoline combustion emissions (11%). The other seven sources accounted for the remaining 16% of the PM2.5. Results obtained at the CMU site were comparable to results previously reported at the National Energy Technology Laboratory (NETL), located approximately 18 km south of downtown Pittsburgh. The major contributor at both sites was material transported from the west and southwest. Some difference in nearby sources could be attributed to meteorology as evaluated by HYSPLIT model back-trajectory calculations. These findings are consistent with the majority of the secondary ammonium sulfate in the Pittsburgh area being the result of contributions from distant transport, and thus decoupled from local activity involving organic pollutants in the metropolitan area. In contrast, the major local secondary sources were dominated by organic material.

Apportionment of primary and secondary pollutants during a July 2001 intensive study at the National Energy Technology Laboratory is reported. PM2.5 was apportioned into primary and secondary contributions using PMF2, and results were compared with apportionment based on UNMIX 2.3. Input to PMF2 included PM2.5 mass data from four per 24 hour PC-BOSS filters and TEOM, NOx, NO2, O3, non-volatile, semi-volatile, and volatile organic material, elemental carbon, sulfate, and PIXE determined trace metals. Nine factors were identified in the PMF analysis. Six factors were associated with primary particles from crustal, mobile (gasoline and diesel), and three local sources high in trace metals. Three factors were associated with secondary sources. Two were associated with local emissions dominated by organic material, one was dominated by transported ammonium sulfate. UNMIX was able to identify the two major mobile sources, major local secondary source and transported secondary source. The three major sources of ...

The Salt Lake City EPA Environmental Monitoring for Public Access and Community Tracking (EMPACT) project, initiated in October 1999, is designed to evaluate the usefulness of a newly developed real-time continuous monitor (RAMS) for total (non-volatile plus semi-volatile) PM2.5 mass and the health relevance of PM2.5 measured by this method as compared to other measurements of PM2.5 parameters. Ammonium nitrate and semi-volatile organic compounds (SVOC) are significant components of fine particles in many urban atmospheres. These components however, are not properly measured by current EPA accepted methods, such as the PM2.5 FRM, due to loss of semi-volatile material (SVM) from the filter during sampling. Continuous PM2.5 mass measurements are attempted using methods such as the R&P TEOM monitor. This method however, heats the sample to remove particle-bound water. This results in evaporation of significant amounts of semi-volatile material. Similarly, continuous carbonaceous material monitors are expected to lose semi-volatile organic material during sample collection. Continuous RAMS and collocated TEOM monitor data have been obtained at the EMPACT sampling site in Salt lake City, Utah during a 2-year period. Results obtained for the continuous determination of total PM2.5 mass with the RAMS have been validated by comparison with results obtained from collocated PC-BOSS diffusion denuder integrated samples at the EMPACT sampling site in Salt Lake City, Utah during three intensive sampling periods (winter 1999–2000, summer 2000, and winter 2000–2001). While the RAMS is shown to measure total PM2.5, including semi-volatile nitrate and organic material, commercially available semi-continuous TEOM and C monitors do not reliably measure these species.

Lichens are known to accumulate airborne elements. This characteristic makes them useful as biomonitors of air quality. However, direct correlations of element concentrations in the air with element concentrations in lichen thalli are generally unavailable. The purpose of this study was to quantitatively examine the relationship between concentrations of copper in ambient air samples and thalli of foliose and fruticose lichens. Lichen samples from four sites along an air copper gradient were collected and analyzed. Foliose specimens consistently accumulated more than twice as much copper as fruticose specimens at all four sites. The relationship between copper concentrations in foliose and fruticose lichens and ambient air samples along an airborne copper gradient was examined using a stepwise regression model. An R2 value of (0.84) and an F-statistic of (182.5, p

Growth form and substrate influences on elemental accumulation patterns were investigated in four lichen species. Two fruticose species (Usnea amblyoclada on rock and Usnea hirta on bark) and two foliose species (Flavoparmelia caperata on rock and Flavopunctelia flaventior on bark) were collected below Massai Point in Chiricahua National Monument in southeastern Arizona, U.S.A. Samples were analyzed for 14 elements. A two-way ANOVA model was used to examine the relationships between substrate and growth form (independent variables) on element accumulation (dependent variable) patterns in lichen samples. In the ANOVA model the growth form variable was significant for K, Ca, Ti, Ba, Fe, Ni Cu, Zn, Pb, Rb, and Sr while the substrate variable was significant for K, Ti, Mn, Fe, Ni, Rb, and Sr. A significant interaction between the two class variables was observed for P, K, Ti, Mn, Fe Ni, Rb, and Sr. Accumulation of sulfur appeared to be independent of both growth form and substrate influences. In this...

14C/C ratios in samples from radial transects across individual thalli of Caloplaca trachyphylla collected at two sites were measured and the results used to investigate whether 14C/C data might provide some insight into the magnitude of carbon turnover in this lichen species. The 14C/C data suggest that significant internal recycling/translocation of carbon is unlikely in the sampled thalli. However, converting the 14C/C data for the larger intact thalli sampled at each site to calendar years, using the atmospheric ⊃14C record, does not yield constant or even monotonically varying growth rates. Since crustose lichen growth rates are constant or decrease with thallus size, and since the 14C/C data from these larger thalli show a relatively small spread in 14C/C data values compared to the Northern Hemisphere atmospheric ⊃14C record over the past 50 years, the 14C/C data suggest that carbon turnover may be occurring. Carbon turnover was modelled starting with the atmospheric ⊃14C record. Turnover was incorporated so that for each year in the record a constant percentage of the total carbon was lost annually and replaced by new photosynthetically fixed carbon with a 14C/C ratio equal to that of the contemporary atmosphere. The 14C/C data from the radial samples were then converted to a calendar year using the model record. Constant annual carbon turnover values of 0, 0·5, 1, 1·5, 2, 2·5, 3, 3·5, 4, 4·5, 5, 5·5, 6, 7, 8, 9, 10, 15, 20, 25 and 50% were modelled. Carbon turnover values between 3 and 6% created ⊃14C model records that when applied to 14C/C data from the thalli produced constant radial growth rates that were: (1) identical for all lichens at a given site, and (2) independent of lichen size at a given site. The 14C/C data further indicate that annual carbon turnover in this species of lichen is 14C/C data from the thalli and might explain the discrepancies between the standard atmospheric ⊃14C record and the 14C/C ratios observed in C. trachyphylla.

PM2.5 mass was measured daily with three batch samplers, a PM2.5 R&P Partisol-Plus FRM, an Andersen RAAS, and a BYU PC-BOSS, and continuously with a TEOM monitor during July and August 2000. PM2.5 composition was also determined. These data are part of an ongoing PM2.5 characterization program centered around a sampling site at the National Energy Technology Laboratory Pittsburgh campus. The composition and concentrations of PM2.5 were both highly variable during this time period. Likely sources of PM2.5 during low concentration periods were transportation, coal-fired boiler, and other emissions generated in the local area. For these periods, the average concentration of PM2.5 was 13 μg/m3 and 70% of the PM2.5 mass was carbonaceous material, including semivolatile organic material that was lost in varying degrees from both the TEOM and FRM samplers. In contrast, much higher concentrations of PM2.5 were associated with transport of pollutants to the site. Analysis of meteorological and back-trajectory data...

The concentration and composition of PM2.5 has been measured with a variety of continuous and integrated samplers at the Hawthorne EPA Environmental Monitoring for Public Awareness and Community Tracking (EMPACT) sampling site in Salt Lake City, UT, and at an EPA Science to Achieve Results (STAR) sampling site in Bountiful, UT. Data are considered at both sites during a 10-day winter period with high PM2.5 concentrations due to winter inversions, and at the Hawthorne site only during a fourteen day summer period when the site was impacted by smoke from wildfires in the Wasatch Mountains. The PM2.5 was dominated by organic material and ammonium nitrate in the winter and by organic material in the summer. In both cases, substantial amounts of sem-volatile material, SVM, was present which was not measured by a Tapered Element Oscillating Microbalance (TEOM) monitor but was detected by a Real-Time Ambient Mass Sampler (RAMS). The PM2.5 data have been combined with concentrations of particulate soot and soil c...

Lichen samples were collected and observations about lichen communities were recorded at sites in the intermountain western United States. Specifically the states of Idaho, Montana, Wyoming, Nevada, Utah, Colorado, Arizona, and New Mexico were included in this study. The minor and trace-element concentrations in many of the lichens collected were determined by proton induced X-ray emission (PIXE). These data are part of a base line assessment of current air pollution conditions in this region. These data also provide an opportunity to study some aspects of lichen physiology. Using the data from 508 foliose and fruticose lichens, frequency distributions for concentrations of phosphorus and calcium are considered. Phosphorus has a closely-spaced, bimodal distribution: one mode for foliose lichens and one mode for fruticose lichens. This suggests that all lichen genera in this study have similar requirements and absorption mechanisms for phosphorus. Calcium has a complex frequency distribution and concentrations that range from 450 mg/kg to 14 % dry weight. Contributions to this complex distribution pattern can be understood if the data are resolved into growth form, genera within each growth form, and in some cases species within a given genus. This complex dependence on calcium is strong evidence that lichens develop specific calcium-related adaptations in order to accommodate various habitat conditions.

Radial 14C/C profiles across three individuals of the crustose lichen Rhizocarpon geographicum (L.) DC. have been determined using accelerator mass spectrometry. These data were used to assess whether lifespan estimates can be determined in this species using 14C/C isotope ratio measurements. 14C/C profiles are relatively flat with Δ14C values (deviations from the modern radiocarbon standard) for the radial samples displaying a small spread ranging from 130 to 200 per mil. The data are consistent with carbon cycling based on growth patterns involving replacement and fusion of areoles within the thallus as well as or instead of cellular or molecular replacement. Consequently, lifespan estimates cannot be obtained from 14C/C measurements of this species and the Δ14C profiles provide no insights into whether the relationship between size and age is linear or curvilinear in this species.

Sections of the crustose saxicolous lichen, Caloplaca trachyphylla, were dated using 14C accelerator mass spectrometry (AMS). The data show a stron linear dependence of radial position on time (r=0.993), suggesting a constant radial growth rate. This specimen had averaged a marginal growth rate of 1.48 mm/year. Extrapolation of the growth curve yields a thallus age of 20 years. These data demonstrate the feasibility of using AMS technology to precisely date lichen tissues and determine growth rates of lichen thalli.

In order to better understand the distribution pattern of mineral elements in lichen tissues, thin sections (15 μm) of the foliose, vagrant soil lichen Xanthoparmelia chlorochroa were examined using proton microprobe Particle induced X-ray emission (PIXE). This technique was used to make two-dimensional scans, with 5 μm resolution, across tissue cross sections of the test species. Element maps for Si, P, S, Cl, K, Ca, Ti, Mn, Fe, Cu, Zn, and As have been prepared. Several elements are strongly localized in the element maps. PIXE data are complimented with STIM, light micrographs, and SEM images. Preliminary data suggest that nuclear microprobe techniques may be useful in elucidating element absorption and transport mechanisms in lichens.

The foundations for building a large research‐ and service‐orientated library automation environment are examined. The coordinating efforts between the UW‐Madison campus library community and administrative library committees overseeing the Electronic Library are described. The collaborative relationship between these committees, technical and non‐technical library staff, and library technology development, integration and support efforts is discussed.

Outlines the problems and challenges faced by the University of Wisconsin with the integration of GIS tools within the electronic library resources. Briefly details the introduction of the system before outlining its abilities and benefits. Considers the training required by library staff. Discusses the ways of testing and evaluating such a project and presents a model testing such a project within a future proposed environment. Considers new potential technology enhancements.

Four broad area for future development in the digital library environment are identified and explored. The presentation and display of information is linked to interface design issues and the types of data and services that might be made available. The challenge of organizing resources and services into virtual collections, often based on vendor, product name, or levels of bibliographic access, is considered. Issues concerning the technical architecture of library systems and data are described, including multi‐tiered architecture, broadcast search capabilities, and support for a growing diversity of data formats. Rights management and access controls related to resource integrity and user security are discussed.

Air pollutants were collected in Logan, Cache County, UT, in February 1993 during two periods of atmospheric inversion accompanied by fog. The following atmospheric species were determined: (1) gaseous SO2, NO2 (semi-quantitatively),HNO3, NH3, and HF; (2) fine particulate SO4 =, NO3 -, NH4 +, F–, H+, C, Si, S, K, Ca, Ti, Mn, Fe, Ni, Cu, Zn, Pb, Se, Br, and Sr, and; (3) fine particulate mass, which was calculated. The major components of fine particulate matter were carbonaceous material, ammonium nitrate, and ammonium sulfate, while the soil component was small. Calculated, fine particulate mass averaged 80 μg/m3 and reached concentrations as high as 120 μg/m3. SO2/Sox and NO2/NOy mole ratios generally varied between 0.2 and 0.1 during inversions. These ratios also showed moderate but consistent diurnal patterns. The emission inventory for Cache County indicates sources of SO2 and NOx but not significant amounts of primary sulfate and nitrate. The observations reported here indicate there is sign...

Total fluoride (gas plus fine particle), spherical aluminosilicate particles, particulate selenium, arsenic, lead, bromine, and absorption of light by fine particles have been used to characterize chemical profiles for sources of sulfur oxides impacting the Grand Canyon National Park Class I Visibility Region. During the Project MOHAVE (Measurement of Haze and Visual Effects) winter and summer intensive studies in 1992, these various species were determined at seven sampling sites in and around the Grand Canyon. Extensive upper air and surface-based meteorological measurements were examined to determine probable geographical origins of the air mass present during a given sampling period for each sampling site. Samples corresponding to air masses dominated by transport from a single major source region were used to determine a source profile for each region. Source regions which have been characterized by this analysis include the San Joaquin Valley area, the southern California coastal urban area, the Baja, California-Imperial Valley area, the Arizona and Mexico area (including major smelters) south of the Grand Canyon, the area southeast of the Grand Canyon, the Colorado Plateau area, the Wasatch Front in Utah, and the area in Nevada to the west and northwest of the Grand Canyon. Source profiles giving the ratio of each endemic marker to SO x for each identified regional source in these areas have been determined. The source profiles for the various regional sources are all statistically different and distinguishable from those for other geographically adjoining sources.

Thirty-six lichen samples that were collected from five wilderness areas and a national monument in the intermountain western United States have been analyzed by PIXE for the determination of 21 elements: P, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Br, Rb, Sr, Ba, and Pb. Samples were powdered and spiked with Y as an internal standard. The powder was analyzed directly as a sample of moderate thickness. Elemental concentration means and ranges were generally consistent with concentration ranges from other studies of unimpacted lichens. Some samples, however, had high concentrations of S, Cu, As, and a few other elements. There are interpretations of the data that imply some wilderness areas are being impacted to some degree by industrial-plant atmospheric emissions.

Hair samples were obtained from ten mummies of the archaic and formative cultures of the north coast of Chile. Each sample was divided into two portions. One portion was washed in acetone and then water and the second portion remained unwashed. All samples were then prepared by an acid digestion procedure and analyzed by PIXE. The washed and unwashed samples were compared to determine what elements were present in the material on the hair surface. Concentrations of the elements Ca, Ti, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Sr, and Pb are reported. Comparison was made to previously published elemental analyses of mummy hair and modern hair. One sample, which had a reddish hue, was found to contain unusually large quantities of Fe and As. Since the unwashed sample had much higher concentrations of these elements than the washed sample, it is believed that the reddish color originated in a mineral dye applied to the hair.

Self-supporting foils of aluminum oxide in the thickness range 100 to 300 nm were prepared by anodic oxidation of aluminum foil and subsequent dissolution of the unreacted aluminum. The foil thicknesses were measured by scanning electron microscopy. Using these foils, stopping cross sections of aluminum oxide for protons and deuterons were measured for particles in the energy range 0.90 to 2.50 MeV. These measured stopping cross sections are compared to other literature results and to the theoretical values as predicted by Bragg's Rule.

Materials containing a significant silicate matrix are often considered for element analysis by the PIXE method. In some circumstances such materials may not be conveniently prepared for sample analysis. It has been found that a lithium metaborate fusion-acid dissolution procedure works well for converting siliceous materials into solution from which thin-target PIXE samples may be made. We have demonstrated that this method will allow rapid and accurate element analysis. The lithium metaborate, however, creates a matrix residue leading to the requirement for sample thickness corrections and an increase in detection limits. We have found this to be a useful sample-preparation method.

One of the primary components of the background in PIXE spectra is secondary electron bremsstrahlung (SEB). However, in order to evaluate the integral usually used to calculate SEB cross sections, certain simplifications must be made, such as assuming an infinite target thickness. In order to more realistically model the physical processes involved in SEB, a Monte Carlo approach is useful. SEB cross sections are calculated by Monte Carlo techniques and the results are compared with the work of Ishii, Morita, and Tarawa [Phys. Rev. A13 (1976) 131; Int. J. PIXE l (1990) 1]. To demonstrate the flexibility of the Monte Carlo method, effects due to the target thickness and the proton-electron cross section are examined.

Six samples of fossilized dinosaur bone and surrounding rock were analyzed by PIXE to investigate general relations between the bone and rock. The powdered samples were brought into an acid solution by a lithium metaborate fusion process. The data were analyzed with chemometric methods to successfully differentiate the bone samples from the complementary rock samples. The Sr/Ca ratio is consistently higher in fossilized bone than the surrounding rock. Ba, Y and U, when found in the rock, appear in significantly higher concentrations in the bone. S and Ti, elements commonly found in rock samples, are not found in the bone samples.

The reasons for using the services of a library automation consultant are numerous, but the key reason is to obtain help—expertise—not already available in the library staff. When a decision to use a consultant is made, the consultant should be identified, selected, and hired through a careful review process. Not all consultants are equal in ability or share the same areas of expertise. Once a consultant is hired, the library must continuously evaluate the consulting process and provide feedback to the consultant so that necessary adjustments can be made. This symposium presents the related insights and perspectives of both librarians and library system vendors.

Fine particulate matter (PM2.5) concentrations associated with 202 24-hr samples collected at the National Energy Technology Laboratory (NETL) particulate matter (PM) characterization site in south Pittsburgh from October 1999 through September 2001 were used to apportion PM2.5 into primary and secondary contributions using Positive Matrix Factorization (PMF2). Input included the concentrations of PM2.5 mass determined with a Federal Reference Method (FRM) sampler, semi-volatile PM2.5 organic material, elemental carbon (EC), and trace element components of PM2.5. A total of 11 factors were identified. The results of potential source contributions function (PSCF) analysis using PMF2 factors and HYSPLIT-calculated back-trajectories were used to identify those factors associated with specific meteorological transport conditions. The 11 factors were identified as being associated with emissions from various specific regions and facilities including crustal material, gasoline combustion, diesel combustion, and three nearby sources high in trace metals. Three sources associated with transport from coal-fired power plants to the southeast, a combination of point sources to the northwest, and a steel mill and associated sources to the west were identified. In addition, two secondary-material-dominated sources were identified, one was associated with secondary products of local emissions and one was dominated by secondary ammonium sulfate transported to the NETL site from the west and southwest. Of these 11 factors, the four largest contributors to PM2.5 were the secondary transported material (dominated by ammonium sulfate) (47%), local secondary material (19%), diesel combustion emissions (10%), and gasoline combustion emissions (8%). The other seven factors accounted for the remaining 16% of the PM2.5 mass. The findings are consistent with the major source of PM2.5 in the Pittsburgh area being dominated by ammonium sulfate from distant transport and so decoupled from local activity emitting organic pollutants in the metropolitan area. In contrast, the major local secondary sources are dominated by organic material.

The intensity of X-rays from PIXE (particle induced X-ray emission) analysis of particulate matter may be reduced relative to that expected from thin samples because of two effects: reduced X-ray cross sections due to proton energy loss, and X-ray attenuation. An equation has been derived for the correction of reduced X-ray intensities emitted from spherical particles. An arbitrary but homogeneous particle composition is assumed. A single particle size or a particle size distribution may be selected. The angle of X-ray detection relative to the incident beam may also be selected. Calculations for X-ray emission lines from sodium to tin have been made for several particle compositions, several radius values and a particle size distribution. It was surprising to find that attenuation corrections were independent of detection angle for all emission lines and particle sizes studied.

This research evaluates the merits of road pricing scenarios affecting a single industry almost exclusively – grain movement on the rural road network in the west central region of the Canadian province of Saskatchewan. Policies in the Canadian grain handling and transportation industry have led to increased use of rural roads, accelerating road deterioration in the region. Using a simulated optimization framework to compare road pricing schemes, we find that a policy of differential road pricing based on known road maintenance costs generates the lowest total social costs. The differences between the simulated social costs in the pricing scenarios are surprisingly small.

Lichens have been shown to be effective biomonitors of air quality. They are currently being used to characterize background element levels and to identify air pollution effects on federally administered lands in the Rocky Mountain region of the western United States. PIXE analysis for twenty elements has been performed on over two hundred lichen specimens collected from various national forests, national monuments, and national parks in the region. This paper reports on patterns of iron and titanium accumulation in lichen tissues. Data show a strong relationship between concentrations of iron and titanium. The Fe/Ti ratios agree well with values reported in similar lichen studies; however, our values for both iron and titanium concentrations are ten times greater than other reports. A distribution function for the log of iron concentrations is distinctly bimodal. The lower concentration mode contains fruticose lichens from bark substrates and the higher concentration mode contains foliose lichens from rock substrates. High iron concentrations in fruticose lichens along the Wasatch Front suggest air pollution impact from a local steel plant.Lichens have been shown to be effective biomonitors of air quality. They are currently being used to characterize background element levels and to identify air pollution effects on federally administered lands in the Rocky Mountain region of the western United States. PIXE analysis for twenty elements has been performed on over two hundred lichen specimens collected from various national forests, national monuments, and national parks in the region. This paper reports on patterns of iron and titanium accumulation in lichen tissues. Data show a strong relationship between concentrations of iron and titanium. The Fe/Ti ratios agree well with values reported in similar lichen studies; however, our values for both iron and titanium concentrations are ten times greater than other reports. A distribution function for the log of iron concentrations is distinctly bimodal. The lower concentration mode contains fruticose lichens from bark substrates and the higher concentration mode contains foliose lichens from ro...

Sulfur transformation chemistry was studied in the plume of the Utah smelter of Kennecott Copper Corporation from April to October 1977. Samples were taken at up to four locations from 4 to 60 km from the stacks. Data collected at each station included: SO2 concentration, low-volume collected total paniculate matter, high-volume collected size fractionated paniculate matter, wind velocity and direction, temperature, and relative humidity. Paniculate samples were analyzed for S(IV). sulfate, strong acid, anions, cations, and elemental concentrations using calorimetric, ion Chromatographie, FIXE, ESCA, ion microprobe, and SEM-ion microprobe techniques. The concentration of As in the paniculate matter was used as a conservative plume tracer. The ratios Mo/As, Pb/As, and Zn/As were constant in particulate matter collected at all sampling sites for any particle size. Strong mineral acid was neutralized by background metal oxide and/or carbonate particulates within 40km of the smelter. This neutralization process is limited only by the rate of incorporation of basic material into the plume. Two distinct metal-S(IV) species similar to those observed in laboratory aerosol experiments were found in the plume. The formation of paniculate S(IV) species occurs by interaction of SO2 (g) with both ambient and plume derived aerosol and is equilibrium controlled. The extent of formation of S(IV) complexes in the aerosol is directly proportional to the SO2(g) and paniculate (Cu + Fe) concentration and inversely proportional to the paniculate acidity. S(IV) species were stable in collected paniculate matter only in the neutralized material, but with proper sampling techniques could be demonstrated to also be present in very acidic particles at high ambient SO2(g) concentrations. Reduction of arsenate to arsenite by the aerosol S(IV) complexes during plume transport is suggested. The SO2(g)-sulfate conversion process in the plume is described by a mechanism which is first order in SO2(g). Equations are derived describing sulfur chemistry when both S(IV) and sulfate formation occur in a plume. The formation of sulfate results primarily in the formation of < 0.5 μm particulates. The formation process is not correlated with plume expansion, paniculate acidity, metal content, or S(IV) species. Due to meteorological restrictions on sampling, data were collected only during periods of maximum insolation. The formation of sulfate from SO2(g) in the plume during periods of high insolation is temperature dependent with an apparent activation energy of 16.6 ± 1.4 kcal mol−1 and a k1, value of 0.039h−1 at 25°C.

Etude de la conversion SO 2 en sulfate dans le panache d'une centrale electrique chauffee au petrole situee pres de la cote Pacifique

The method of proton particle induced X-ray emission (proton PIXE) has been used by several teams of researchers for minor and trace element analysis of many interesting biological samples. The proton PIXE analysis method is often ideal for such samples because it allows for the simultaneous determination of several elements and requires only a small sample. Difficult problems are often encountered in preparing samples suitable for PIXE analysis and considerable imagination has been used to solve these problems. Samples both thick and thin in comparison to the particle-beam range have been used. Thin samples are usually supported on thin foils. Procedures used in preparing thins samples have included wet ashing, dry ashing, nebulization of a suspension, freeze-drying, sectioning with a microtome, and spiking with noninterfering elements. Each method of sample analysis has advantages which must be understood when choosing a method for a particular problem.

A single-acid, wet-digestion method using nitric acid has been used to prepare samples for element analysis by thin-target, particle induced X-ray emission (PIXE). The method involves repeated cycles of heating in acid and charring until a clear solution is obtained. Good recovery of elements is observed and matrix reduction is achieved. The method has been successfully applied to organic, carbonaceous and a few other inorganic samples that were in a variety of chemical and physical forms.

Automation developments of individual libraries are viewed as a mid-range plateau leading toward involvement in networks. The primary issues of machine-readable record formats, holdings formats mechanisms for updating machine-readable databases, and system interfaces for hardware, software, and operating systems need to be addressed if the local developments are to be a step toward the library's eventual networking capabilities. Libraries and the bibliographic networks are all progressing in their use of computer technology, but not necessarily toward a common goal.

The chemical composition of two copper and three lead smelter flue dust samples has been studied by wet chemical analysis techniques for sulfite, sulfate, arsenite, anenate, chloride, fluoride, phosphate and acid species; by photoetoctron spectroscopy; by X-ray diffraction analysis; and by proton induced X-ray emission spectroscopy. The results indicate the acidity, chemical composition, and time stability of the flue samples varies greatly. Specific components identified in the samples include; sulfate, sulfite, bisulfate, elemental sulfur, sulfide, arsenite, arsenate, arsenic suifide, chloride, fluoride, phosphate, Fe(II), Fe(III), total trace metal composition, and the specific compounds As 2 O 3 , PbSO 4 , PbO · PbSO 4 , ZnO, Fe 3 O 4 , and Fe 2 O 3 . Acidity, and die chemical components controlling acidity vary widely among the samples studied. Comparisons of the bulk and surface composition of the samples indicate that the surface species cannot be predicted from the bulk composition. From the data obtained, satisfactory total mass and charge balance is obtained for the major (> 1 wt%) components present in the flue dusts studied.

A FORTAN program, NANOLEX, has been developed for the analysis of particle induced X-ray spectra. Background components are stripped from a spectrum and recursive relations are employed to strip away contributions of non-Gaussian peak components. A technique known as linearization of a Gaussian is used to determined an energy scale and a good estimate of peak intensities. Ideal Gaussian spectra are generated for elements in the sample and a Fletcher-Powell optimization method is used in a linear least-squares fitting of ideal spectra to the stripped experimental spectrum. The program has been developed with both small and large computer versions.

Proton particle-induced x-ray emission (proton PIXE) analysis has been used for the determination of minor and trace element concentrations in obsidian artifacts. Thin targets were made from the acid digests of 30 to 100 mg of finely powdered obsidian samples. Concentrations are reported for K, Ca, Tl, Ba, Mn, Fe, Zn, Ga, Rb, Sr, and Zr. Forty-nine obsidian artifacts from Northern Campeche, Mexico, were analyzed. Methods used for the association of obsidian artifacts with geological sources are illustrated.

Recent epidemiological and animal lexicological studies indicate that reactions between SO2 and metal containing aerosols result in the formation of respiratory irritants. These studies point out the importance of understanding in detail the chemical species formed by such interactions. Using a combination of thermometric, ESCA and PIXE analysis techniques, it has been demonstrated that both inorganic and organic S(IV) species are stable constituents of aerosols associated with pollution sources containing SO2 and transition metals or with pollution sources resulting from the combustion of fossil fuels. The data indicate the inorganic sulfite species are present as complexes with Fe(III), Cu(II), Zn(II) and possibly Pb(II). The concentration of these inorganic sulfite species is 10 to 30% of the sulfate concentration in primary aerosols produced by smelters. These inorganic sulfite species tend to be evenly distributed over the various particle sizes. In contrast, the inorganic sulfite in primary aerosols produced by fossil fuel burning sources tends to exist in the

Effluents from a high temperature, high pressure, entrained flow gasifier were analysed for possible inorganic and organic pollutants. The effluents and product gases from this type of reactor are very clean compared to those produced in established commercial gasification processes. The only major potential pollutants are the particulate matter and NH4+ in the scrubber water, the bottom ash, and the H2S and HCN in the product and flash gases. All of the non-volatile organic compounds produced are quantitatively adsorbed by the particulate matter in the scrubber water. Increasing the pressure and decreasing the O2coal ratio tended to reduce pollutants in the effluents and increase coal conversion efficiency.

Various links between acquisitions and circulation systems are possible whether manual or automated. Design considerations of such interfaces between vendor and/or in-house systems must consider record formats, linking data fields, and future demands of maintaining the interface. The greatest advantages to circulation and acquisitions functions are generally realized in the areas of transferring rather than recreating data, as well as collection development information. Benefits to other library functions and programs must also be considered in the overall development and evaluation.

Negative errors as large as 50% may occur in particle induced x-ray emission (PIXE) determinations of sulfur concentration in environmental samples. The low values obtained by PIXE in this study are due to chemical reactions induced by irradiation and to loss of sulfur species which are volatile at the temperatures produced by the particle beam under some conditions. The use of small beam currents can eliminate the losses due to simple heating but not those due to radiation-induced reactions. 4 tables.

Proton particle-induced X-ray emission (PIXE) analysis has been used to determine the concentrations of K, Ca, Ti, Mn, Fe, Co, Ni, Cu, Zn, Se, Br, Rb, Sr, Cd, Cs, and Pb in liver, spleen, aorta, kidney medulla, kidney cortex, abdominal fat, pancreas, and hair taken at autopsy from Southwest Indians, primarily of the Pima tribe. Samples were prepared by a low-temperature ashing procedure which is compared to other preparation methods. Data were analyzed by a computer program, ANALEX. The accuracy is tested with NBS standard reference materials and with flame atomic absorption spectrophotometric results. The precision allowed observation of element concentration differences between replicate, half-gram samples of the same tissue. The differences appeared to arise from tissue inhomogeneities. 5 figures, 4 tables.

Obsidian artifacts from Edzna, Dzibilnocac, and Santa Rosa Xtampak in northern Campeche, Mexico, have been analyzed by means of X-ray fluorescence in order to determine their trace element composition. The results are compared to the trace element composition of obsidian sources in Guatemala and Mexico. It is postulated that the obsidian from the three sites in northern Campeche came from highland Guatemala, mostly from El Chayal. Our data are compared to the published data of other archaeological sites in Mesoamerica from which obsidian samples have been analyzed. Finally, obsidian transport routes are postulated between northern Campeche, Mexico, and highland Guatemala.

Particle induced X-ray emission (PIXE) analysis is a highly versatile method of element analysis. Thus it is well suited for use as a complement to other methods of analysis in experimental programs requiring both chemical and elemental analyses. This paper reports some results of two projects where PIXE was used in conjunction with titration calorimetry, ion chromatography, atomic absorption spectroscopy, gas chromatography/mass spectrometry, X-ray fluorescence spectroscopy and some other methods. The first is a study of sulfur chemistry in a copper smelter plume. Arsenic was found to be a conservative tracer of the plume and was used for calculation of plume dilution. Calcium was found to be characteristic of the background or ambient aerosol and was used to correct particulate data for the background contribution. The use of both plume and ambient tracers and of data from other analytical methods noted above led to the determination of several aspects of the plume sulfur chemistry. The second project is a study of the effluents from a high-temperature, high-pressure entrained flow gasifier. The scrubber water and particulate matter entrained in the scrubber water and in the product gas were analyzed by PIXE. Of particular interest were the low elemental concentrations in the scrubber water.

Papers reporting the application of particle induced X-ray emission (PIXE) analysis to biological samples continue to appear regularly in the literature. The majority of these papers deal with blood, hair, and other common body organs while a few deal with biological samples from the environment. A variety of sample preparation methods have been demonstrated, a number of which are improvements, refinements and extensions of the thick- and thin-sample preparation methods reported in the early development of PIXE. While many papers describe the development of PIXE techniques some papers are now describing application of the methods to serious biological problems. The following two factors may help to stimulate more consistent use of the PIXE method. First, each PIXE facility should be organized to give rapid sample processing and should have available several sample preparation and handling methods. Second, those with the skill to use PIXE methods need to become closely associated with researchers knowledgeable in medical and biological sciences and they also need to become more involved in project planning and sample handling.