NASA Technical Reports Server (NTRS)
Pun, A.; Papike, J. J.
1994-01-01
We are evaluating the trace-element concentrations in the pyroxenes of Pasamonte. Pasamonte is a characteristic member of the main group eucrites, and has recently been redescribed as a polymict eucrite. Our Pasamonte sample contained eucritic clasts with textures ranging from subophitic to moderately coarse-grained. This study concentrates on pyroxenes from an unequilibrated, coarse-grained eucrite clast. Major-, minor-, and trace-element analyses were measured for zoned pyroxenes in the eucritic clast of Pasamonte. The major- and minor-element zoning traverses were measured using the JEOL 733 electron probe with an Oxford-Link imaging/analysis system. Complemenatry trace elements were then measured for the core and rim of each of the grains by SIMS. The trace elements analyzed consisted of eight REE, Sr, Y, and Zr. These analyses were performed on a Cameca 4f ion probe. The results of the CI chondrite normalized (average CI trace-element analyses for several grains and the major- and minor-element zoning patterns from a single pyroxene grain are given. The Eu abundance in the cores of the pyroxenes represents the detection limit and therefore the (-Eu) anomaly is a minimum. Major- and minor-element patterns are typical for igneous zoning. Pyroxene cores are Mg enriched, whereas the rims are enriched in Fe and Ca. Also, Ti and Mn are found to increase, while Cr and Al generally decrease in core-to-rim traverses. The cores of the pyroxenes are more depleted in the Rare Earth Elements (REE) than the rims. Using the minor- and trace-element concentrations of bulk Pasamonte and the minor- and trace-element concentrations from the cores of the pyroxenes in Pasamonte measured in this study, we calculated partition coefficients between pyroxene and melt. This calculation assumes that bulk Pasamonte is representative of a melt composition.
Piper, D.Z.; Isaacs, C.M.
1995-01-01
Approximately 24 samples of the Monterey Formation, Southern California, have been analyzed for their major-element oxide and minor-element content. These analyses allow identification of a detrital fraction, composed of terrigenous quartz, clay minerals, and other Al silicate minerals, and a marine fraction, composed of biogenic silica, calcite, dolomite, organic matter, apatite, and minor amounts of pyrite. The minor-element contents in the marine fraction alone are interpreted to have required, at the time of deposition, a high level of primary productivity in the photic zone and denitrifying bacterial respiration in the bottom water.
Seawater as the source of minor elements in black shales, phosphorites and other sedimentary rocks
Piper, D.Z.
1994-01-01
Many of the minor elements in seawater today have a concentration-depth profile similar to that of the biologically essential nutrients, NO-3 and PO3-4. They show a relative depletion in the photic zone and enrichment in the deep ocean. The difference between their surface- and deep-ocean values, normalized to the change in PO3-4, approaches the average of measured minor-element: P ratios in marine plankton, although individual analyses of the latter show extreme scatter for a variety of reasons. Despite this scatter in the minor-element analyses of plankton, agreement between the two sets of data shows unequivocally that an important marine flux of many minor elements through the ocean is in the form of biogenic matter, with a composition approaching that of plankton. This interpretation is further supported by sediment studies, particularly of sediments which accumulate in shelf-slope environments where biological productivity in the photic zone is exceptionally high and organic carbon contents of the underlying sediment elevated. The interelement relations observed for some of these sediments approach the average values of plankton. These same interelement relations are observed in many marine sedimentary rocks such as metalliferous black shales and phosphorites, rocks which have a high content of marine fractions (e.g., organic matter, apatite, biogenic silica and carbonates). Many previous studies of the geochemistry of these rocks have concluded that local hydrothermal activity, and/or seawater with an elemental content different from that of the modern ocean, was required to account for their minor-element contents. However, the similarity in several of the minor-element ratios in many of these formations to minor-element ratios in modern plankton demonstrates that these sedimentary rocks accumulated in environments whose marine chemistry was virtually identical to that seen on continental shelf-slopes, or in marginal seas, of the ocean today. The accumulation of the marine fraction of minor elements on these ancient sea floors was determined largely by the accumulation of organic matter, settling from the photic zone and with a composition of average plankton. A second marine fraction of minor elements in these rocks accumulated through precipitation and adsorption from seawater. The suite of elements in this fraction reflects redox conditions in the bottom water, as determined by bacterial respiration. For example, high Mn, high Cr+V and high Mo concentrations, above those which can be attributed to the accumulation of planktonic matter, characterize accumulation under bottom-water oxidizing, denitrifying and sulfate-reducing conditions, respectively. ?? 1994.
NASA Technical Reports Server (NTRS)
Steele, I. M.; Smith, J. V.; Skirius, C.
1985-01-01
Cathodoluminescence has been applied to look for textural features of olivine in carbonaceous meteorites relevant to the unresolved dispute over the origin of the olivine, whether from a vapor or a liquid. Cathodoluminescence photographs of forsterite grains in Murchison (C2) and Allende (C3) meteorites presented here reveal a blue core with planar boundaries to a red or dark rim. High-precision electron microprobe analyses have been performed which reveal unusually large amounts of the 'minor' elements Al, Ti, and Ca in the blue cores of these forsterites, suggesting formation by crystallization at high temperatures from a source rich in these metals. Following conclusions drawn from previous analyses of olivine in meteorites, it is argued that the minor element signature should be able to characterize olivines in micrometeorites and in deep-sea particles.
NASA Astrophysics Data System (ADS)
Denniston, Rhawn F.; Shearer, Charles K.; Layne, Graham D.; Vaniman, David T.
1997-05-01
Fracture-lining calcite samples from Yucca Mountain, Nevada, obtained as part of the extensive vertical sampling in studies of this site as a potential high-level waste repository, have been characterized according to microbeam-scale (25-30 μm) trace and minor element chemistry, and cathodoluminescent zonation patterns. As bulk chemical analyses are limited in spatial resolution and are subject to contamination by intergrown phases, a technique for analysis by secondary ion mass spectrometry (SIMS) of minor (Mn, Fe, Sr) and trace (REE) elements in calcite was developed and applied to eighteen calcite samples from four boreholes and one trench. SIMS analyses of REE in calcite and dolomite have been shown to be quantitative to abundances < 1 × chondrite. Although the low secondary ion yields associated with carbonates forced higher counting times than is necessary in most silicates, Mn, Fe, Sr, and REE analyses were obtained with sub-ppm detection limits and 2-15% analytical precision. Bulk chemical signatures noted by Vaniman (1994) allowed correlation of minor and trace element signatures in Yucca Mountain calcite with location of calcite precipitation (saturated vs. unsaturated zone). For example, upper unsaturated zone calcite exhibits pronounced negative Ce and Eu anomalies not observed in calcite collected below in the deep unsaturated zone. These chemical distinctions served as fingerprints which were applied to growth zones in order to examine temporal changes in calcite crystallization histories; analyses of such fine-scale zonal variations are unattainable using bulk analytical techniques. In addition, LREE (particularly Ce) scavenging of calcite-precipitating solutions by manganese oxide phases is discussed as the mechanism for Ce-depletion in unsaturated zone calcite.
John A. McLean; P. Laks; T.L. Shore
1983-01-01
Western spruce budworm were reared on three host foliages and artificial medium. Trace element analyses showed large differences in elemental concentrations between food sources and only minor differences between insect life stages. Discriminant analyses were carried out to test the distinctiveness of adult chemoprints from each rearing regime. Fe, Cu, and Zn were...
Lyons, P.C.; Morelli, J.J.; Hercules, D.M.; Lineman, D.; Thompson-Rizer, C. L.; Dulong, F.T.
1990-01-01
A study of the elemental composition of intimately associated coal macerals in the English Swallow Wood coal bed was conducted using a laser microprobe mass analyser, and indicated a similar trace and minor elemental chemistry in the vitrinite and cutinite and a different elemental signature in the fusinite. Three to six sites were analysed within each maceral during the study by laser micro mass spectrometry (LAMMS). Al, Ba, Ca, Cl, Cr, Dy, F, Fe, Ga, K, Li, Mg, Na, S, Si, Sr, Ti, V, and Y were detected by LAMMS in all three macerals but not necessarily at each site analysed. The signal intensities of major isotopic peaks were normalized to the signal intensity of the m z 85 peak (C7H) to determine the relative minor- and trace-element concentrations among the three dominant macerals. The vitrinite and the cutinite were depleted in Ba, Ca, Dy, Li, Mg, Sr, and Y relative to their concentrations observed in the fusinite. The cutinite was distinguished over vitrinite by less Ti, V, Cr and Ca, and K Ca $ ??1 (relative signal intensities). The fusinite, relative to the cutinite and vitrinite, was relatively depleted in Cr, Sc, Ti, and V. The fusinite, as compared with both the cutinite and vitrinite, was relatively enriched in Ba, Ca, Dy, Li, Mg, Sr, and Y, and also showed the most intense m z 64, 65, 66 signals (possibly S2+, HS2+, H2S2+, respectively). The LAMMS data indicate a common source for most elements and selective loss from the maceral precursors in the peat or entrapment of certain elements as mineral matter, most likely during the peat stage or during early diagenesis. The relatively high amounts of Ba, Ca, Dy, Li, Mg, Sr, and Y in the fusinite are consistent with micron and submicron mineral-matter inclusions such as carbonates and Ca-Al phosphates (probably crandallite group minerals). Mineralogical data on the whole coal, the LAMMS chemistry of the vitrinite and cutinite, and scanning electron microscopy/energy dispersive X-ray analysis (SEM/EDAX) of the elements in the macerals are consistent with the presence of micron and submicron inclusions of clays such as kaolinite, illite, and Ca-rich or Ca-bearing minerals (e.g. calcite, Ca-Al phosphates, and illite) which are different in kind and proportions in the three macerals. The variance as measured by the F-statistic for all three macerals indicates generally a nonuniform distribution of minor and trace elements in all three macerals, thus supporting a mineral-matter (inorganic) origin of the elements analysed. Exceptions are Al, K, Fe, Ga, and Sr in the vitrinite and cutinite, which is consistent with organic complexing or a uniform distribution of micron or submicron mineral matter such as illite and phosphate(s). ?? 1990.
Bunburra Rockhole: Exploring the geology of a new differentiated asteroid
NASA Astrophysics Data System (ADS)
Benedix, G. K.; Bland, P. A.; Friedrich, J. M.; Mittlefehldt, D. W.; Sanborn, M. E.; Yin, Q.-Z.; Greenwood, R. C.; Franchi, I. A.; Bevan, A. W. R.; Towner, M. C.; Perrotta, G. C.; Mertzman, S. A.
2017-07-01
Bunburra Rockhole is the first recovered meteorite of the Desert Fireball Network. We expanded a bulk chemical study of the Bunburra Rockhole meteorite to include major, minor and trace element analyses, as well as oxygen and chromium isotopes, in several different pieces of the meteorite. This was to determine the extent of chemical heterogeneity and constrain the origin of the meteorite. Minor and trace element analyses in all pieces are exactly on the basaltic eucrite trend. Major element analyses show a slight deviation from basaltic eucrite compositions, but not in any systematic pattern. New oxygen isotope analyses on 23 pieces of Bunburra Rockhole shows large variation in both δ17O and δ18O, and both are well outside the HED parent body fractionation line. We present the first Cr isotope results of this rock, which are also distinct from HEDs. Detailed computed tomographic scanning and back-scattered electron mapping do not indicate the presence of any other meteoritic contaminant (contamination is also unlikely based on trace element chemistry). We therefore conclude that Bunburra Rockhole represents a sample of a new differentiated asteroid, one that may have more variable oxygen isotopic compositions than 4 Vesta. The fact that Bunburra Rockhole chemistry falls on the eucrite trend perhaps suggests that multiple objects with basaltic crusts accreted in a similar region of the Solar System.
LA-ICP-MS of magnetite: Methods and reference materials
Nadoll, P.; Koenig, A.E.
2011-01-01
Magnetite (Fe3O4) is a common accessory mineral in many geologic settings. Its variable geochemistry makes it a powerful petrogenetic indicator. Electron microprobe (EMPA) analyses are commonly used to examine major and minor element contents in magnetite. Laser ablation ICP-MS (LA-ICP-MS) is applicable to trace element analyses of magnetite but has not been widely employed to examine compositional variations. We tested the applicability of the NIST SRM 610, the USGS GSE-1G, and the NIST SRM 2782 reference materials (RMs) as external standards and developed a reliable method for LA-ICP-MS analysis of magnetite. LA-ICP-MS analyses were carried out on well characterized magnetite samples with a 193 nm, Excimer, ArF LA system. Although matrix-matched RMs are sometimes important for calibration and normalization of LA-ICP-MS data, we demonstrate that glass RMs can produce accurate results for LA-ICP-MS analyses of magnetite. Cross-comparison between the NIST SRM 610 and USGS GSE-1G indicates good agreement for magnetite minor and trace element data calibrated with either of these RMs. Many elements show a sufficiently good match between the LA-ICP-MS and the EMPA data; for example, Ti and V show a close to linear relationship with correlation coefficients, R2 of 0.79 and 0.85 respectively. ?? 2011 The Royal Society of Chemistry.
Molybdenite Mineral Evolution: A Study Of Trace Elements Through Time
NASA Astrophysics Data System (ADS)
McMillan, M. M.; Downs, R. T.; Stein, H. J.; Zimmerman, A.; Beitscher, B. A.; Sverjensky, D. A.; Papineau, D.; Armstrong, J. T.; Hazen, R. M.
2010-12-01
Mineral evolution explores changes through time in Earth’s near-surface mineralogy, including diversity of species, relative abundances of species, and compositional ranges of major, minor and trace elements. Such studies elucidate the co-evolution of the geosphere and biosphere. Accordingly, we investigated trace and minor elements in molybdenite (MoS2) with known ages from 3 billion years to recent. Molybdenite, the commonest mineral of Mo, may prove to be a useful case study as a consequence of its presence in Earth’s early history, the effects of oxidation on Mo mobility, and the possible role of Mo mineral coevolution with biology via its role in the nitrogen fixation enzyme nitrogenase. We employed ICPMS, SEM and electron microprobe analyses to detect trace and minor elements. We detected significant amounts of Mn and Cu (~100 ppm) and greater amounts of Fe, W, and Re (to ~4000 ppm). Molybdenites commonly contain micro inclusions, resulting in local concentrations in otherwise homogeneous samples. Inhomogeneities in Fe, Zn and Sn concentrations, for example, point to the presence of pyrite, sphalerite and cassiterite inclusions, respectively. Analyses examined as a function of time reveal that samples containing significant concentrations (>200 ppm, compared to average values < 100 ppm) of W and Re formed primarily within the last billion years. These trends may reflect changes in the mobility of W and Re in oxic hydrothermal fluids at shallow crustal conditions following the Great Oxidation Event.
Andrew Fowler
2015-10-01
Compilation of rare earth element and associated major and minor dissolved constituent analytical data for USA geothermal fields and global seafloor hydrothermal vents. Data is in original units. Reference to and use of this data should be attributed to the original authors and publications according to the provisions outlined therein.
Forster, H.-J.; Davis, J.C.; Tischendorf, G.; Seltmann, R.
1999-01-01
High-precision major, minor and trace element analyses for 44 elements have been made of 329 Late Variscan granitic and rhyolitic rocks from the Erzgebirge metallogenic province of Germany. The intrusive histories of some of these granites are not completely understood and exposures of rock are not adequate to resolve relationships between what apparently are different plutons. Therefore, it is necessary to turn to chemical analyses to decipher the evolution of the plutons and their relationships. A new classification of Erzgebirge plutons into five major groups of granites, based on petrologic interpretations of geochemical and mineralogical relationships (low-F biotite granites; low-F two-mica granites; high-F, high-P2O5 Li-mica granites; high-F, low-P2O5 Li-mica granites; high-F, low-P2O5 biotite granites) was tested by multivariate techniques. Canonical analyses of major elements, minor elements, trace elements and ratio variables all distinguish the groups with differing amounts of success. Univariate ANOVA's, in combination with forward-stepwise and backward-elimination canonical analyses, were used to select ten variables which were most effective in distinguishing groups. In a biplot, groups form distinct clusters roughly arranged along a quadratic path. Within groups, individual plutons tend to be arranged in patterns possibly reflecting granitic evolution. Canonical functions were used to classify samples of rhyolites of unknown association into the five groups. Another canonical analysis was based on ten elements traditionally used in petrology and which were important in the new classification of granites. Their biplot pattern is similar to that from statistically chosen variables but less effective at distinguishing the five groups of granites. This study shows that multivariate statistical techniques can provide significant insight into problems of granitic petrogenesis and may be superior to conventional procedures for petrological interpretation.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bankston, D.C.; Humphris, S.E.; Thompson, G.
1979-07-01
A technique for the determination of major concentrations of SiO/sub 2/, Al/sub 2/O/sub 3/, Fe/sub 2/O/sub 3/, MgO, CaO, Na/sub 2/O, and K/sub 2/O, minor levels of TiO/sub 2/, P/sub 2/O/sub 5/, and MnO, and trace concentrations of Ba, Cr, Cu, Ni, Sr, V, and Zn, in semi-microsamples 200 mg) of powdered whole rock, is described. Chemically diverse standard reference rocks are used both for calibration and assessment of accuracy. A lithium metaborate fusion melt of each standard or sample is dissolved in dilute HNO/sub 3/ containing Cs/sup +/ at a level of 0.2% (w/v). The resulting solution is usedmore » to perform all analyses except those for Na/sub 2/O and K/sub 2/O, which are determined in a portion of the original sample solution wherein the Cs/sup +/ concentration has been raised to 0.32% (w/v). Analyses of both portions of each sample solution are performed using an optical emission spectrometer/spectrograph equipped with an echelle monochromator and a dc argon plasma excitation source. Trace element detection limits ranged from 2 ppM for Cu to 15 ppM for Zn. A study of precision based on replicate determinations in three splits of the proposed USGS reference basalt BHVO-1 yielded the following results: (1) For analyses of the major and minor oxide constituents, values of the percent relative standard deviation (RSD) ranged from 1 for CaO, to 21 for P/sub 2/O/sub 5/. 2) For trace element determinations, values of the RSD ranged from 2 for Cu, to 19 for Zn. 2 figures, 11 tables.« less
Minor elements in Keweenawan lavas, Michigan
Cornwall, H.R.; Rose, H.J.
1957-01-01
The distribution of minor elements in three basaltic flows of the Keweenawan series, of Michigan, is related to differentiation in the flows. Thus, nickel is most abundant in the early differentiates; nickel, chromium, and barium are generally deficient in the pegmatites, which formed late; whereas copper, vanadium, yttrium, and other minor elements are concentrated in the pegmatites. The minor-element content of individual minerals in the Greenstone flow varies markedly from one mineral to another and seems to depend primarily on the presence or absence in the minerals of major elements for which the minor elements can substitute. Minor elements have substituted most readily for those major elements with similar ionic radii. Valence and electronegativity also seem to influence the ease of substitution. The distribution of other minor elements in copper-bearing lodes of the Michigan copper district shows no apparent relation to copper mineralization. ?? 1957.
Vicenzi, Edward P.; Eggins, Stephen; Logan, Amelia; Wysoczanski, Richard
2002-01-01
An initial study of the minor element, trace element, and impurities in Corning archeological references glasses have been performed using three microbeam techniques: electron probe microanalysis (EPMA), laser ablation ICP-mass spectrometry (LA ICP-MS), and secondary ion mass spectrometry (SIMS). The EPMA results suggest a significant level of heterogeneity for a number of metals. Conversely, higher precision and a larger sampling volume analysis by LA ICP-MS indicates a high degree of chemical uniformity within all glasses, typically <2 % relative (1 σ). SIMS data reveal that small but measurable quantities of volatile impurities are present in the glasses, including H at roughly the 0.0001 mass fraction level. These glasses show promise for use as secondary standards for minor and trace element analyses of insulating materials such as synthetic ceramics, minerals, and silicate glasses. PMID:27446764
Williams Element with Generalized Degrees of Freedom for Fracture Analysis of Multiple-Cracked Beam
NASA Astrophysics Data System (ADS)
Xu, Hua; Wei, Quyang; Yang, Lufeng
2017-10-01
In this paper, the method of finite element with generalized degrees of freedom (FEDOFs) is used to calculate the stress intensity factor (SIF) of multiple cracked beam and analysed the effect of minor cracks on the main crack SIF in different cases. Williams element is insensitive to the size of singular region. So that calculation efficiency is highly improved. Examples analysis validates that the SIF near the crack tip can be obtained directly though FEDOFs. And the result is well consistent with ANSYS solution and has a satisfied accuracy.
Investigation of drinking water quality in Kosovo.
Berisha, Fatlume; Goessler, Walter
2013-01-01
In the recent years, not much environmental monitoring has been conducted in the territory of Kosovo. This study represents the first comprehensive monitoring of the drinking water situation throughout most of the territory of Kosovo. We present the distribution of major and minor trace elements in drinking water samples from Kosovo. During our study we collected 951 samples from four different sources: private-bored wells; naturally flowing artesian water; pumped-drilled wells; and public water sources (tap water). The randomly selected drinking water samples were investigated by routine water analyses using inductively coupled plasma mass spectrometry (ICPMS) for 32 elements (Li, Be, B, Na, Mg, Al, K, Ca, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, As, Rb, Sr, Mo, Ag, Cd, Sn, Sb, Te, Ba, Tl, Pb, Bi, Th, U). Even though there are set guidelines for elemental exposure in drinking water worldwide, in developing countries, such as Kosovo, the lack of monitoring drinking water continues to be an important health concern. This study reports the concentrations of major and minor elements in the drinking water in Kosovo. Additionally, we show the variation of the metal concentration within different sources. Of the 15 regulated elements, the following five elements: Mn, Fe, Al, Ni, As, and U were the elements which most often exceeded the guidelines set by the EU and/or WHO.
Ion microprobe mass analysis of lunar samples. Lunar sample program
NASA Technical Reports Server (NTRS)
Anderson, C. A.; Hinthorne, J. R.
1971-01-01
Mass analyses of selected minerals, glasses and soil particles of lunar, meteoritic and terrestrial rocks have been made with the ion microprobe mass analyzer. Major, minor and trace element concentrations have been determined in situ in major and accessory mineral phases in polished rock thin sections. The Pb isotope ratios have been measured in U and Th bearing accessory minerals to yield radiometric age dates and heavy volatile elements have been sought on the surfaces of free particles from Apollo soil samples.
Hair analyses: worthless for vitamins, limited for minerals.
Hambidge, K M
1982-11-01
Despite many major and minor problems with interpretation of analytical data, chemical analyses of human hair have some potential value. Extensive research will be necessary to define this value, including correlation of hair concentrations of specific elements with those in other tissues and metabolic pools and definition of normal physiological concentration ranges. Many factors that may compromise the correct interpretation of analytical data require detailed evaluation for each specific element. Meanwhile, hair analyses are of some value in the comparison of different populations and, for example, in public health community surveys of environmental exposure to heavy metals. On an individual basis, their established usefulness is much more restricted and the limitations are especially notable for evaluation of mineral nutritional status. There is a wide gulf between the limited and mainly tentative scientific justification for their use on an individual basis and the current exploitation of multielement chemical analyses of human hair.
Deducing Wild 2 Components with a Statistical Dataset of Olivine in Chondrite Matrix
NASA Technical Reports Server (NTRS)
Frank, D. R.; Zolensky, M. E.; Le, L.
2012-01-01
Introduction: A preliminary exam of the Wild 2 olivine yielded a major element distribution that is strikingly similar to those for aqueously altered carbonaceous chondrites (CI, CM, and CR) [1], in which FeO-rich olivine is preferentially altered. With evidence lacking for large-scale alteration in Wild 2, the mechanism for this apparent selectivity is poorly understood. We use a statistical approach to explain this distribution in terms of relative contributions from different chondrite forming regions. Samples and Analyses: We have made a particular effort to obtain the best possible analyses of both major and minor elements in Wild 2 olivine and the 5-30 micrometer population in chondrite matrix. Previous studies of chondrite matrix either include larger isolated grains (not found in the Wild 2 collection) or lack minor element abundances. To overcome this gap in the existing data, we have now compiled greater than 10(exp 3) EPMA analyses of matrix olivine in CI, CM, CR, CH, Kakangari, C2-ungrouped, and the least equilibrated CO, CV, LL, and EH chondrites. Also, we are acquiring TEM/EDXS analyses of the Wild 2 olivine with 500s count times, to reduce relative errors of minor elements with respect to those otherwise available. Results: Using our Wild 2 analyses and those from [2], the revised major element distribution is more similar to anhydrous IDPs than previous results, which were based on more limited statistics (see figure below). However, a large frequency peak at Fa(sub 0-1) still persists. All but one of these grains has no detectable Cr, which is dissimilar to the Fa(sub 0-1) found in the CI and CM matrices. In fact, Fa(sub 0-1) with strongly depleted Cr content is a composition that appears to be unique to Kakangari and enstatite (highly reduced) chondrites. We also note the paucity of Fa(sub greater than 58), which would typically indicate crystallization in a more oxidizing environment [3]. We conclude that, relative to the bulk of anhydrous IDPs, Wild 2 may have received a larger contribution from the Kakangari and/or enstatite chondrite forming regions. Alternatively, Wild 2 may have undergone accretion in an anomalously reducing region, marked by nebular condensation of this atypical forsterite. In [4], a similar conclusion was reached with an Fe-XANES study. We will also use similar lines of reasoning, and our previous conclusions in [5], to constrain the relative contributions of silicates that appear to have been radially transported from different ordinary and carbonaceous chondrite forming regions to the Kuiper Belt. In addition, the widespread depletion of Cr in these FeO-rich (Fa(sub greater than 20)) fragments is consistent with mild thermal metamorphism in Wild 2.
The Apollo 17 'melt sheet' - Chemistry, age and Rb/Sr systematics
NASA Technical Reports Server (NTRS)
Winzer, S. R.; Nava, D. F.; Schuhmann, S.; Philpotts, J. A.; Schuhmann, P. J.; Lum, R. K. L.; Lindstrom, M. M.; Lindstrom, D. J.
1977-01-01
Major, minor, and trace-element compositions, age data, and Rb/Sr systematics of Apollo 17 boulders have been compiled, and additional analyses performed on a norite breccia clast (77215) included in the Apollo 17, Station 7 boulder. The Apollo 17 boulders are found to be identical or nearly so in major, minor, and trace-element composition, suggesting that they all originated as an impact melt analogous to melt sheets found in larger terrestrial craters. The matrix dates (Ar-40/Ar-39) and Rb/Sr systematics available suggest that this impact melt formed by a single impact about 4 billion years ago. This impact excavated, shocked, brecciated, and melted norites, norite cumulates, and possibly anorthositic gabbros and dunites about 4.4 billion years old. The impact was likely a major one, possibly the Serenitatis basin-forming event.
Investigation of Drinking Water Quality in Kosovo
Berisha, Fatlume; Goessler, Walter
2013-01-01
In the recent years, not much environmental monitoring has been conducted in the territory of Kosovo. This study represents the first comprehensive monitoring of the drinking water situation throughout most of the territory of Kosovo. We present the distribution of major and minor trace elements in drinking water samples from Kosovo. During our study we collected 951 samples from four different sources: private-bored wells; naturally flowing artesian water; pumped-drilled wells; and public water sources (tap water). The randomly selected drinking water samples were investigated by routine water analyses using inductively coupled plasma mass spectrometry (ICPMS) for 32 elements (Li, Be, B, Na, Mg, Al, K, Ca, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, As, Rb, Sr, Mo, Ag, Cd, Sn, Sb, Te, Ba, Tl, Pb, Bi, Th, U). Even though there are set guidelines for elemental exposure in drinking water worldwide, in developing countries, such as Kosovo, the lack of monitoring drinking water continues to be an important health concern. This study reports the concentrations of major and minor elements in the drinking water in Kosovo. Additionally, we show the variation of the metal concentration within different sources. Of the 15 regulated elements, the following five elements: Mn, Fe, Al, Ni, As, and U were the elements which most often exceeded the guidelines set by the EU and/or WHO. PMID:23509472
Perceived sibling relationships of sexual minority youth.
Toomey, Russell B; Richardson, Rhonda A
2009-01-01
The purpose of this study was to examine the relationships of sexual minority youth and their siblings. The participants were 56 lesbian, gay, bisexual, or transgender individuals ranging in age from 18 to 24 years, who reported information about a total of 107 siblings. Respondents completed a demographic data questionnaire as well as adapted versions of the Sibling Closeness Scale (SCS) and the Sibling Approval of Sexual Behavior Scale (SASBS) to describe their relationship with each of their siblings. Analyses examined birth order and gender in relation to outness to siblings as well as sibling closeness and approval. Results provide information about disclosure of LGBT status to siblings, elements of closeness and acceptance in sibling relationships of sexual minority youth, and the significance of gender and birth order in these sibling relationships.
NASA Technical Reports Server (NTRS)
Germani, M. S.; Bradley, J. P.; Brownlee, D. E.
1990-01-01
A 200 keV electron microscope was used to obtain elemental analyses from over 4000 points on thin sections of eight 'layer silicate' class interplanetary dust particles (IDPs). Major and minor element abundances from a volume approaching that of a cylinder 50 nm in diameter were observed. Mineral phases and their relative abundances in the thin sections were identified and petrographic characteristics were determined. Three of the particles contained smectite (1.0-1.2 nm basal spacing) and two contained serpentine (0.7 nm basal spacing). The point count analyses and Mg-Si-Fe ternary diagrams show that one of the serpentine-containing IDPs is similar to CI and CM chondritic meteorites. The IDPs exhibit evidence of aqueous processing, but they have typically experienced only short range, submicrometer scale alteration. The IDPs may provide a broad sampling of the asteroid belt.
Distribution and Phase Association of Some Major and Trace Elements in the Arabian Gulf Sediments
NASA Astrophysics Data System (ADS)
Basaham, A. S.; El-Sayed, M. A.
1998-02-01
Twenty-four sediment samples were collected from the Arabian Gulf (ROPME Sea) and analysed for their grain size distribution and carbonate contents as well as the major elements Ca, Mg, Fe and Al and macro and trace elements Mn, Sr, Ba, Zn, Cu, Cr, V, Ni and Hg. Concentration of trace elements are found comparable to previous data published for samples taken before and after the Gulf War, and reflect the natural background level. Grain size analyses, aluminium and carbonate measurements support the presence of two major sediment types: (1) a terrigenous, fine-grained and Al rich type predominating along the Iranian side; and (2) a coarse-grained and carbonate rich type predominating along the Arabian side of the Gulf. Investigation of the correlation of the elements analysed with the sediment type indicates that they could be grouped under two distinct associations: (1) carbonate association including Ca and Sr; and (2) terrigenous association comprising Al, Fe, Mg, Ba, Mn, Zn, Cu, Cr, V, Ni and Hg. Element/Al ratios calculated for the mud non-carbonate fraction indicate that the Euphrates and Tigris rivers have minor importance as sediment sources to the Gulf. Most of the elements have exceptionally high aluminium ratios in sediments containing more than 85-90% carbonate. These sediments are restricted to the southern and south-eastern part of the area where depth is shallow and temperature and salinity are high. Both biological accumulation and chemical and biochemical coprecipitation could be responsible for this anomaly.
Keatley, A C; Scott, T B; Davis, S; Jones, C P; Turner, P
2015-12-01
Minor element composition and rare earth element (REE) concentrations in nuclear materials are important as they are used within the field of nuclear forensics as an indicator of sample origin. However recent studies into uranium ores and uranium ore concentrates (UOCs) have shown significant elemental and isotopic heterogeneity from a single mine site such that some sites have shown higher variation within the mine site than that seen between multiple sites. The elemental composition of both uranium and gangue minerals within ore samples taken along a single mineral vein in South West England have been measured and reported here. The analysis of the samples was undertaken to determine the extent of the localised variation in key elements. Energy Dispersive X-ray spectroscopy (EDS) was used to analyse the gangue mineralogy and measure major element composition. Minor element composition and rare earth element (REE) concentrations were measured by Electron Probe Microanalysis (EPMA). The results confirm that a number of key elements, REE concentrations and patterns used for origin location do show significant variation within mine. Furthermore significant variation is also visible on a meter scale. In addition three separate uranium phases were identified within the vein which indicates multiple uranium mineralisation events. In light of these localised elemental variations it is recommended that representative sampling for an area is undertaken prior to establishing the REE pattern that may be used to identify the originating mine for an unknown ore sample and prior to investigating impact of ore processing on any arising REE patterns. Copyright © 2015 Elsevier Ltd. All rights reserved.
Chemical composition and origin of black patinas on granite.
Silva, Benita; Aira, Noelia; Martínez-Cortizas, Antonio; Prieto, Beatriz
2009-12-15
Black patinas from the surfaces of granite outcrops (including some with engravings) and granite buildings were analysed. Rock samples were also taken from areas of the same surfaces where there were no black patinas. The constituent elements of the granite rocks, elements of essentially biological origin (C, N, H) and other minor elements, including some typical from pollution, were all determined. The ratios between the concentrations of each element in the patinas and in the corresponding rock samples without patina were calculated in order to determine which elements form the patinas. The data were then examined by hierarchical cluster analysis and principal components analysis to establish the factors that determine the differences between samples. It was found that the elements that differentiate the patinas from the samples of rock without patina are those unrelated to granite, which indicates that, at least from a geochemical point of view, the rocky substrate does not affect patina formation. In all patinas analysed, the concentrations of carbon were higher than in the corresponding samples without patina; there were also relatively higher concentrations of sulphur, phosphorus, chlorine, calcium, etc. in some patinas, depending on the situation of the outcrop or monument.
Mineralogy of Drill Cuttings Beowawe, Dixie Valley and Roosevelt Hot Springs
Simmons, Stuart
2017-01-25
Mineralogical, lithological, and geospatial data of drill cuttings from exploration production wells in Beowawe, Dixie Valley and Roosvelt Hot Springs. These data support whole rock analyses for major, minor and critical elements to assess critical metals in produced fluids from Nevada and Utah geothermal fields. The samples were analyzed by x-ray diffraction (legacy data) and then checked by thin section analysis.
A view on elemental distribution alterations of coronary artery walls in atherogenesis
NASA Astrophysics Data System (ADS)
Pallon, J.; Homman, P.; Pinheiro, T.; Halpern, M. J.; Malmqvist, K.
1995-09-01
In this study, the Nuclear Microprobe technique was employed to investigate the elemental concentration alterations of minor and trace elements at the different cellular layers and structures of freeze-dried cryosections of human coronary arteries. Nuclear microprobe analyses enable to determine 7 elements, i.e., P, S, Cl, K, Ca, Fe and Zn in the artery walls. Furthermore, it was possible to identify early modifications of the artery due to the atherosclerosis progression that cannot be detected with specific staining or conventional histological methods. These modifications are shown to be related to abnormal Fe and Zn depositions in the surroundings of the elastic laminae. Later on, the calcifications of these regions occur, contributing to the elastic laminae damage and leading to the atheroma growing and maturation.
Trace and minor elements in sphalerite from metamorphosed sulphide deposits
NASA Astrophysics Data System (ADS)
Lockington, Julian A.; Cook, Nigel J.; Ciobanu, Cristiana L.
2014-12-01
Sphalerite is a common sulphide and is the dominant ore mineral in Zn-Pb sulphide deposits. Precise determination of minor and trace element concentrations in sulphides, including sphalerite, by Laser-Ablation Inductively-Coupled-Plasma Mass-Spectrometry (LA-ICP-MS) is a potentially valuable petrogenetic tool. In this study, LA-ICP-MS is used to analyse 19 sphalerite samples from metamorphosed, sphalerite-bearing volcanic-associated and sedimentary exhalative massive sulphide deposits in Norway and Australia. The distributions of Mn, Fe, Co, Cu, Ga, Se, Ag, Cd, In, Sn, Sb, Hg, Tl, Pb and Bi are addressed with emphasis on how concentrations of these elements vary with metamorphic grade of the deposit and the extent of sulphide recrystallization. Results show that the concentrations of a group of trace elements which are believed to be present in sphalerite as micro- to nano-scale inclusions (Pb, Bi, and to some degree Cu and Ag) diminish with increasing metamorphic grade. This is interpreted as due to release of these elements during sphalerite recrystallization and subsequent remobilization to form discrete minerals elsewhere. The concentrations of lattice-bound elements (Mn, Fe, Cd, In and Hg) show no correlation with metamorphic grade. Primary metal sources, physico-chemical conditions during initial deposition, and element partitioning between sphalerite and co-existing sulphides are dominant in defining the concentrations of these elements and they appear to be readily re-incorporated into recrystallized sphalerite, offering potential insights into ore genesis. Given that sphalerite accommodates a variety of trace elements that can be precisely determined by contemporary microanalytical techniques, the mineral has considerable potential as a geothermometer, providing that element partitioning between sphalerite and coexisting minerals (galena, chalcopyrite etc.) can be quantified in samples for which the crystallization temperature can be independently constrained.
Tellurium content of marine manganese oxides and other manganese oxides
Lakin, H.W.; Thompson, C.E.; Davidson, D.F.
1963-01-01
Tellurium in amounts ranging from 5 to 125 parts per million was present in all of 12 samples of manganese oxide nodules from the floor of the Pacific and Indian oceans. These samples represent the first recognized points of high tellurium concentration in a sedimentary cycle. The analyses may lend support to the theory that the minor-element content of seafloor manganese nodules is derived from volcanic emanations.
Igneous fractionation and subsolidus equilibration of diogenite meteorites
NASA Technical Reports Server (NTRS)
Mittlefehldt, David W.
1993-01-01
Diogenites are coarse-grained orthopyroxenite breccias of remarkably uniform major element composition. Most diogenites contain homogeneous pyroxene fragments up to 5 cm across of Wo2En74Fs24 composition. Common minor constituents are chromite, olivine, trolite and metal, while silica, plagioclase, merrillite and diopside are trace phases. Diogenites are generally believed to be cumulates from the eucrite parent body, although their relationship with eucrites remains obscure. It has been suggested that some diogenites are residues after partial melting. I have performed EMPA and INAA for major, minor and trace elements on most diogenites, concentrating on coarse-grained mineral and lithic clasts in order to elucidate their igneous formation and subsequent metamorphic history. Major element compositions of diogenites are decoupled from minor and trace element compositions; the latter record an igneous fractionation sequence that is not preserved in the former. Low equilibration temperatures indicate that major element diffusion continued long after crystallization. Diffusion coefficients for trivalent and tetravalent elements in pyroxene are lower than those of divalent elements. Therefore, major element compositions of diogenites may represent means of unknown portions of a cumulate homogenized by diffusion, while minor and trace elements still yield information on their igneous history. The scale of major element equilibration is unknown, but is likely to be on the order of a few cm. Therefore, the diogenite precursors may have consisted largely of cm-sized, igneously zoned orthopyroxene grains, which were subsequently annealed during slow cooling, obliterating major element zoning but preserving minor and trace incompatible element zoning.
NASA Technical Reports Server (NTRS)
Hu, H.-N.; Taylor, L. A.
1977-01-01
Rhodes et al. (1975, 1976) and Adams et al. (1975) have reported that the agglutinate fraction of the soils on the lunar surface displays a marked enrichment in Fe, Mg, Ti, K, and La, and a depletion in Ca, Na, Al, and Eu, relative to the bulk soils. The reported investigation is concerned with a testing of the theory of chemical fractionation involving magnetic separation which was developed in connection with these findings. Soils 64421 and 71501 were sieved and the magnetic fractions separated according to the method developed by Adams and McCord (1973). Analyses of agglutinitic glass did not indicate any appreciable chemical fractionation for the major and minor elements accompanying the agglutination process. It was found that most, if not all fractionations reported can be accounted for completely by the magnetic nonagglutinate impurities in the agglutinate fraction. It is, therefore, concluded that there appears to be no reason to make use of any chemical fractionation theory, whose validity remains to be demonstrated.
Back-arc with frontal-arc component origin of Triassic Karmutsen basalt, British Columbia, Canada
Barker, F.; Sutherland, Brown A.; Budahn, J.R.; Plafker, G.
1989-01-01
The largely basaltic, ???4.5-6.2-km-thick, Middle to Upper Triassic Karmutsen Formation is a prominent part of the Wrangellian sequence. Twelve analyses of major and minor elements of representative samples of pillowed and massive basalt flows and sills from Queen Charlotte and Vancouver Islands are ferrotholeiites that show a range of 10.2-3.8% MgO (as normalized, H2O- and CO2-free) and related increases in TiO2 (1.0-2.5%), Zr (43-147 ppm) and Nb (5-16 ppm). Other elemental abundances are not related simply to MgO: distinct groupings are evident in Al2O3, Na2O and Cr, but considerable scatter is present in FeO* (FeO + 0.9Fe2O3) and CaO. Some of the variation is attributed to alteration during low-rank metamorphism or by seawater - including variation of Ba, Rb, Sr and Cu, but high-field-strength elements (Sc, Ti, Y, Zr and Nb) as well as Cr, Ni, Cu and rare-earth elements (REE's) were relatively immobile. REE's show chondrite-normalized patterns ranging from light-REE depleted to moderately light-REE enriched. On eleven discriminant plots these analyses fall largely into or across fields of within-plate basalt (WIP), normal or enriched mid-ocean-ridge tholeiite (MORB) and island-arc tholeiite (IAT). Karmutsen basalts are chemically identical to the stratigraphically equivalent Nikolai Greenstone of southern Alaska and Yukon Territory. These data and the fact that the Karmutsen rests on Sicker Group island-arc rocks of Paleozoic age suggest to us that: 1. (1) the basal arc, after minor carbonate-shale deposition, underwent near-axial back-arc rifting (as, e.g., the Mariana arc rifted at different times); 2. (2) the Karmutsen basalts were erupted along this rift or basin as "arc-rift" tholeiitite; and 3. (3) after subsequent deposition of carbonates and other rocks, and Jurassic magmatism, a large fragment of this basalt-sediment-covered island arc was accreted to North America as Wrangellia. The major- and minor-elemental abundances of Karmutsen basalt is modeled by first mixing primitive arc magma with enriched basaltic liquid derived either from garnet peridotite or metasomatized mantle, followed by fractionation of olivine, pyroxenes, plagioclase and spinel. ?? 1989.
Toxic and essential elements in Lebanese cheese.
Bou Khozam, Rola; Pohl, Pawel; Al Ayoubi, Baydaa; Jaber, Farouk; Lobinski, Ryszard
2012-01-01
Concentrations of 20 minor, trace and ultratrace elements relevant to human health (Ag, Al, As, Cd, Co, Cr, Cu, Fe, Hg, Li, Mn, Mo, Ni, Pb, Sb, Se, Si, Sn, V) were determined in four different varieties of the most consumed cheese in Lebanon (Halloumi, Double Crème, Baladi, Labneh) sampled at five different provinces (Grand Beirut, South of Lebanon, North of Lebanon, Mount of Lebanon and Beka'a) during the wet and dry seasons. The analyses were carried out by double focussing sector field inductively coupled plasma-mass spectrometry (ICP-MS) in order to avoid errors due to polyatomic interferences. Levels of toxic elements (As, Cd, Pb) were generally below the WHO permissible levels in dairy products. Concentrations of most elements were considerably affected by the type of cheese, the geographical site and the season of sampling.
Quantifying Volcanic Emissions of Trace Elements to the Atmosphere: Ideas Based on Past Studies
NASA Astrophysics Data System (ADS)
Rose, W. I.
2003-12-01
Extensive data exist from volcanological and geochemical studies about exotic elemental enrichments in volcanic emissions to the atmosphere but quantitative data are quite rare. Advanced, highly sensitive techniques of analysis are needed to detect low concentrations of some minor elements, especially during major eruptions. I will present data from studies done during low levels of activity (incrustations and silica tube sublimates at high temperature fumaroles, from SEM studies of particle samples collected in volcanic plumes and volcanic clouds, from geochemical analysis of volcanic gas condensates, from analysis of treated particle and gas filter packs) and a much smaller number that could reflect explosive activity (from fresh ashfall leachate geochemistry, and from thermodynamic codes modeling volatile emissions from magma). This data describes a highly variable pattern of elemental enrichments which are difficult to quantify, generalize and understand. Sampling in a routine way is difficult, and work in active craters has heightened our awareness of danger, which appropriately inhibits some sampling. There are numerous localized enrichments of minor elements that can be documented and others can be expected or inferred. There is a lack of systematic tools to measure minor element abundances in volcanic emissions. The careful combination of several methodologies listed above for the same volcanic vents can provide redundant data on multiple elements which could lead to overall quantification of minor element fluxes but there are challenging issues about detection. For quiescent plumes we can design combinations of measurements to quantify minor element emission rates. Doing a comparable methodology to succeed in measuring minor element fluxes for significant eruptions will require new strategies and/or ideas.
NASA Astrophysics Data System (ADS)
Mendes Godinho, R.; Raimundo, J.; Vale, C.; Anes, B.; Brito, P.; Alves, L. C.; Pinheiro, T.
2013-07-01
In the scope of a monitoring program to assess the environmental impact of automobile traffic over one main bridge in Lisbon, both water and duckweed (Lemna minor L.) were sampled from the road drainage tanks and analyzed for chemical elements. Plants uptake Cr, Mn, Cu, and Zn metals from rain water draining the bridge road. Nuclear microprobe elemental maps of cryosections of L. minor tissues showed that incorporated elements were internalized in fronds of the plant. This approach at micrometer level allows a better knowledge of the elemental tissue partitioning in this biomonitor organism.
Yamaoka, Shuhei; Yoshimura, Kazusa; Kondou, Youichi; Onogi, Akio; Matsui, Minami; Iwata, Hiroyoshi; Ban, Tomohiro
2017-01-01
Profiling elemental contents in wheat grains and clarifying the underlying genetic systems are important for the breeding of biofortified crops. Our objective was to evaluate the genetic potential of 269 Afghan wheat landraces for increasing elemental contents in wheat cultivars. The contents of three major (Mg, K, and P) and three minor (Mn, Fe, and Zn) elements in wheat grains were measured by energy dispersive X-ray fluorescence spectrometry. Large variations in elemental contents were observed among landraces. Marker-based heritability estimates were low to moderate, suggesting that the elemental contents are complex quantitative traits. Genetic correlations between two locations (Japan and Afghanistan) and among the six elements were estimated using a multi-response Bayesian linear mixed model. Low-to-moderate genetic correlations were observed among major elements and among minor elements respectively, but not between major and minor elements. A single-response genome-wide association study detected only one significant marker, which was associated with Zn, suggesting it will be difficult to increase the elemental contents of wheat by conventional marker-assisted selection. Genomic predictions for major elemental contents were moderately or highly accurate, whereas those for minor elements were mostly low or moderate. Our results indicate genomic selection may be useful for the genetic improvement of elemental contents in wheat. PMID:28072876
Information Summary, Area of Concern: Grand Calumet River, Indiana
1991-03-01
Indiana Harbor and Adjacent Lake Michigan (Source Rl, Table 4) 10 Concentrations of 26 Major, Minor and Trace Elements in Sediments from Indiana Harbor...2 Dec 84 (Source R39, Table 2) 68 Concentrations of Major, Minor , and Trace Elements in Fish and Crayfish from Indiana Harbor and Adjacent Lake...Table 21b) 71 Catch per Unit Effort in Crayfish Traps (Source Rl, Table 21c) 72 Concentratiors of Major, Minor , and Trace Elements in Periphyton and
Phosphorite-hosted zinc and lead mineralization in the Sekarna deposit (Central Tunisia)
Garnit, Hechmi; Bouhel, Salah; Barca, Donatella; Johnson, Craig A.; Chtara, Chaker
2012-01-01
The Sekarna Zn–Pb deposit is located in Central Tunisia at the northeastern edge of the Cenozoic Rohia graben. Mineralization comprises two major ore types: (1) disseminated Zn–Pb sulfides that occur as lenses in sedimentary phosphorite layers and (2) cavity-filling zinc oxides (calamine-type ores) that crosscut Late Cretaceous and Early Eocene limestone. We studied Zn sulfide mineralization in the Saint Pierre ore body, which is hosted in a 5-m-thick sedimentary phosphorite unit of Early Eocene age. The sulfide mineralization occurs as replacements of carbonate cement in phosphorite. The ores comprise stratiform lenses rich in sphalerite with minor galena, Fe sulfides, and earlier diagenetic barite. Laser ablation–inductively coupled plasma mass spectrometry analyses of sphalerite and galena show a wide range of minor element contents with significant enrichment of cadmium in both sphalerite (6,000–20,000 ppm) and galena (12–189 ppm). The minor element enrichments likely reflect the influence of the immediate organic-rich host rocks. Fluid inclusions in sphalerite give homogenization temperatures of 80–130°C. The final ice melting temperatures range from −22°C to −11°C, which correspond to salinities of 15–24 wt.% NaCl eq. and suggest a basinal brine origin for the fluids. Sulfur isotope analyses show uniformly negative values for sphalerite (−11.2‰ to −9.3‰) and galena (−16‰ to −12.3‰). The δ34S of barite, which averages 25.1‰, is 4‰ higher than the value for Eocene seawater sulfate. The sulfur isotopic compositions are inferred to reflect sulfur derivation through bacterial reduction of contemporaneous seawater sulfate, possibly in restricted basins where organic matter was abundant. The Pb isotopes suggest an upper crustal lead source.
Phosphorite-hosted zinc and lead mineralization in the Sekarna deposit (Central Tunisia)
NASA Astrophysics Data System (ADS)
Garnit, Hechmi; Bouhlel, Salah; Barca, Donatella; Johnson, Craig A.; Chtara, Chaker
2012-06-01
The Sekarna Zn-Pb deposit is located in Central Tunisia at the northeastern edge of the Cenozoic Rohia graben. Mineralization comprises two major ore types: (1) disseminated Zn-Pb sulfides that occur as lenses in sedimentary phosphorite layers and (2) cavity-filling zinc oxides (calamine-type ores) that crosscut Late Cretaceous and Early Eocene limestone. We studied Zn sulfide mineralization in the Saint Pierre ore body, which is hosted in a 5-m-thick sedimentary phosphorite unit of Early Eocene age. The sulfide mineralization occurs as replacements of carbonate cement in phosphorite. The ores comprise stratiform lenses rich in sphalerite with minor galena, Fe sulfides, and earlier diagenetic barite. Laser ablation-inductively coupled plasma mass spectrometry analyses of sphalerite and galena show a wide range of minor element contents with significant enrichment of cadmium in both sphalerite (6,000-20,000 ppm) and galena (12-189 ppm). The minor element enrichments likely reflect the influence of the immediate organic-rich host rocks. Fluid inclusions in sphalerite give homogenization temperatures of 80-130°C. The final ice melting temperatures range from -22°C to -11°C, which correspond to salinities of 15-24 wt.% NaCl eq. and suggest a basinal brine origin for the fluids. Sulfur isotope analyses show uniformly negative values for sphalerite (-11.2‰ to -9.3‰) and galena (-16‰ to -12.3‰). The δ34S of barite, which averages 25.1‰, is 4‰ higher than the value for Eocene seawater sulfate. The sulfur isotopic compositions are inferred to reflect sulfur derivation through bacterial reduction of contemporaneous seawater sulfate, possibly in restricted basins where organic matter was abundant. The Pb isotopes suggest an upper crustal lead source.
NASA Technical Reports Server (NTRS)
Flynn, G. J.; Sutton, S. R.
1990-01-01
Trace element abundance determinations were performed using synchrotron X-ray fluorescence on nine particles collected from the stratosphere and classified as cosmic. Improvements to the Synchrotron Light Source allowed the detection of all elements between Cr and Mo, with the exceptions of Co and As, in our largest particle. The minor and trace element abundance patterns of three Ni-depleted particles were remarkably similar to those of extraterrestrial igneous rocks. Fe/Ni and Fe/Mn ratios suggest that one of these may be of lunar origin. All nine particles exhibited an enrichment in Br, ranging from 1.3 to 38 times the C1 concentration. Br concentrations were uncorrelated with particle size, as would be expected for a surface correlated component acquires from the stratosphere.
Duodu, Godfred Odame; Goonetilleke, Ashantha; Allen, Charlotte; Ayoko, Godwin A
2015-10-22
Wet-milling protocol was employed to produce pressed powder tablets with excellent cohesion and homogeneity suitable for laser ablation (LA) analysis of volatile and refractive elements in sediment. The influence of sample preparation on analytical performance was also investigated, including sample homogeneity, accuracy and limit of detection. Milling in volatile solvent for 40 min ensured sample is well mixed and could reasonably recover both volatile (Hg) and refractive (Zr) elements. With the exception of Cr (-52%) and Nb (+26%) major, minor and trace elements in STSD-1 and MESS-3 could be analysed within ±20% of the certified values. Comparison of the method with total digestion method using HF was tested by analysing 10 different sediment samples. The laser method recovers significantly higher amounts of analytes such as Ag, Cd, Sn and Sn than the total digestion method making it a more robust method for elements across the periodic table. LA-ICP-MS also eliminates the interferences from chemical reagents as well as the health and safety risks associated with digestion processes. Therefore, it can be considered as an enhanced method for the analysis of heterogeneous matrices such as river sediments. Copyright © 2015 Elsevier B.V. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Landis, E.R.; Rohrbacher, T.J.; Gluskoter, H.
1999-07-01
As part of the activities conducted under the U.S. Hungarian Science and Technology Fund, a total of 39 samples from five coal mines in Hungary were selected for standard coal analyses and major, minor and trace elements analysis. The mine areas sampled were selected to provide a spectrum of coal quality information for comparison with other coal areas in central Europe and worldwide. All of the areas are of major importance in the energy budget of Hungary. The five sample sites contain coal in rocks of Jurassic, Cretaceous, Eocene, Miocene, and Pliocene age. The coals, from four underground and onemore » surface mine, range in rank from high volatile bituminous to lignite B. Most of the coal produced from the mines sampled is used to generate electricity. Some of the power plants that utilize the coals also provide heat for domestic and process usage. The standard coal analysis program is based on tests performed in accordance with standards of the American Society for Testing and Materials (ASTM). Proximate and ultimate analyses were supplemented by determinations of the heating value, equilibrium moisture, forms of sulfur, free-swelling index, ash fusion temperatures (both reducing and oxidizing), apparent specific gravity and Hardgrove Grindability index. The major, minor and trace element analyses were performed in accordance with standardized procedures of the U.S. Geological Survey. The analytical results will be available in the International Coal Quality Data Base of the USGS. The results of the program provide data for comparison with test data from Europe and information of value to potential investors or cooperators in the coal industry of Hungary and Central Europe.« less
Thermal changes of the environment and their influence on reinforced concrete structures
NASA Astrophysics Data System (ADS)
Fojtik, R.; Cajka, R.
2018-04-01
The thermal expansion of concrete elements concerns both monolithic and prefabricated structures. Inappropriate design of dilation segments may cause minor but even larger failures. Critical environment factors are temperature-changing operations, such as unheated underground garages, where temperature fluctuations may occur depending on the exterior conditions. This paper numerically and experimentally analyses the thermal deformation of selected girders in the underground garages and the consequent structure failures, their causes, possible prevention and appropriate remediation.
A comparison of methods for evaluating structure during ship collisions
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ammerman, D.J.; Daidola, J.C.
1996-10-01
A comparison is provided of the results of various methods for evaluating structure during a ship-to-ship collision. The baseline vessel utilized in the analyses is a 67.4 meter in length displacement hull struck by an identical vessel traveling at speeds ranging from 10 to 30 knots. The structural response of the struck vessel and motion of both the struck and striking vessels are assessed by finite element analysis. These same results are then compared to predictions utilizing the {open_quotes}Tanker Structural Analysis for Minor Collisions{close_quotes} (TSAMC) Method, the Minorsky Method, the Haywood Collision Process, and comparison to full-scale tests. Consideration ismore » given to the nature of structural deformation, absorbed energy, penetration, rigid body motion, and virtual mass affecting the hydrodynamic response. Insights are provided with regard to the calibration of the finite element model which was achievable through utilizing the more empirical analyses and the extent to which the finite element analysis is able to simulate the entire collision event. 7 refs., 8 figs., 4 tabs.« less
NASA Technical Reports Server (NTRS)
McKay, G.; Schwandt, C.; Le, L.; Mikouchi, T.
2007-01-01
Nakhlites are olivine-bearing clinopyroxene cumulates. Based on petrographic characteristics, they may be divided into groups that cooled at different rates and may have been formed at different depths in a single flow. The order of cooling rate from slowest to fastest is NWA998
EDXRF study of Indian punch-marked silver coins
NASA Astrophysics Data System (ADS)
Vijayan, V.; Rautray, T. R.; Basa, D. K.
2004-09-01
Coins are important archaeological objects that can provide valuable information regarding coin minting methodology and provenance as well as politics and economics of the time. Punch-marked coins are the oldest known numismatics used in ancient India. 23 Indian punch-marked silver coins were analysed, for the first time, by using multi-elemental non-destructive energy dispersive X-ray fluorescence (EDXRF) technique. Our study reveals that silver, copper, iron, gold and lead are the significant constituents of the Indian punch marked silver coins, with minor/trace of elements like Ti, Cr, Co, Ni, As and Y also seems to indicate the fragmentation as well as the impoverishment of the power for the regimes that had produced the studied coins.
NASA Astrophysics Data System (ADS)
Dyar, M. Darby; Fassett, Caleb I.; Giguere, Stephen; Lepore, Kate; Byrne, Sarah; Boucher, Thomas; Carey, CJ; Mahadevan, Sridhar
2016-09-01
This study uses 1356 spectra from 452 geologically-diverse samples, the largest suite of LIBS rock spectra ever assembled, to compare the accuracy of elemental predictions in models that use only spectral regions thought to contain peaks arising from the element of interest versus those that use information in the entire spectrum. Results show that for the elements Si, Al, Ti, Fe, Mg, Ca, Na, K, Ni, Mn, Cr, Co, and Zn, univariate predictions based on single emission lines are by far the least accurate, no matter how carefully the region of channels/wavelengths is chosen and despite the prominence of the selected emission lines. An automated iterative algorithm was developed to sweep through all 5485 channels of data and select the single region that produces the optimal prediction accuracy for each element using univariate analysis. For the eight major elements, use of this technique results in a 35% improvement in prediction accuracy; for minors, the improvement is 13%. The best wavelength region choice for any given univariate analysis is likely to be an inherent property of the specific training set that cannot be generalized. In comparison, multivariate analysis using partial least-squares (PLS) almost universally outperforms univariate analysis. PLS using all the same wavelength regions from the univariate analysis produces results that improve in accuracy by 63% for major elements and 3% for minor element. This difference is likely a reflection of signal to noise ratios, which are far better for major elements than for minor elements, and likely limit their prediction accuracy by any technique. We also compare predictions using specific wavelength ranges for each element against those employing all channels. Masking out channels to focus on emission lines from a specific element that occurs decreases prediction accuracy for major elements but is useful for minor elements with low signals and proportionally much higher noise; use of PLS rather than univariate analysis is still recommended. Finally, we tested the generalizability of our results by analyzing a second data set from a different instrument. Overall prediction accuracies for the mixed data sets are higher than for either set alone for all major and minor elements except Ni, Cr, and Co, where results are roughly comparable.
NASA Technical Reports Server (NTRS)
Larimer, John W.; Ganapathy, R.
1987-01-01
The trace element distribution in oldhamite (CaS) extracted from enstatite chondrites was determined by INAA. Prior to extraction, the petrologic setting of the grains was studied microscopically, and their minor element contents determined by microprobe analysis; samples that displayed a wide range of minor element contents were selected for detailed elementary analysis. Those samples of CaS suspected to be more primitive on the basis of their minor element and petrologic siting contain the entire inventory of the host meteorite's light REE (LREE) and Eu, plus 30-50 percent of the heavy-REE inventory. In less primitive samples, the LREE are less enriched although Eu remains highly concentrated. Several other elements, including lithophiles and chalcophiles, are most enriched in the most primitive CaS. It is suggested that oldhamite played a key role in the redistribution of these elements during the metamorphism and evolution of enstatite-rich material.
The effects of minor elements in La0.6Sr0.4Co0.2Fe0.8O3-δ cathodes on oxygen reduction reaction
NASA Astrophysics Data System (ADS)
Oishi, Junya; Otomo, Junichiro; Oshima, Yoshito; Koyama, Michihisa
2015-03-01
It is known that the minor elements affect the performance of solid oxide fuel cell (SOFC). In this study, we focus on the influence of minor elements on the SOFC cathode properties. The Ca, Ba, Al, and Si, which originate from raw materials and production processes for SOFC cathodes, are investigated as minor elements that may have effect on the properties of La0.6Sr0.4Co0.2Fe0.8O3-δ (LSCF) cathode. To examine the effects of minor elements on the cathode properties, Ca, Ba, Al, and Si with a controlled concentration are added to the LSCF reference sample. Conductivity relaxation measurements are conducted to determine the chemical diffusion coefficient (Dchem) and surface exchange coefficient (ktr), which governs the overpotential characteristics of the LSCF cathode. The results show that Al and Si have negative effects on both Dchem and ktr while Ca and Ba do not alter Dchem and show weakly positive effects on ktr. The effects of Ca and Ba for the cathode properties are discussed on the basis of XPS measurements.
A review of international pharmacy-based minor ailment services and proposed service design model.
Aly, Mariyam; García-Cárdenas, Victoria; Williams, Kylie; Benrimoj, Shalom I
2018-01-05
The need to consider sustainable healthcare solutions is essential. An innovative strategy used to promote minor ailment care is the utilisation of community pharmacists to deliver minor ailment services (MASs). Promoting higher levels of self-care can potentially reduce the strain on existing resources. To explore the features of international MASs, including their similarities and differences, and consider the essential elements to design a MAS model. A grey literature search strategy was completed in June 2017 to comply with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses standard. This included (1) Google/Yahoo! search engines, (2) targeted websites, and (3) contact with commissioning organisations. Executive summaries, table of contents and title pages of documents were reviewed. Key characteristics of MASs were extracted and a MAS model was developed. A total of 147 publications were included in the review. Key service elements identified included eligibility, accessibility, staff involvement, reimbursement systems. Several factors need to be considered when designing a MAS model; including contextualisation of MAS to the market. Stakeholder engagement, service planning, governance, implementation and review have emerged as key aspects involved with a design model. MASs differ in their structural parameters. Consideration of these parameters is necessary when devising MAS aims and assessing outcomes to promote sustainability and success of the service. Copyright © 2018 Elsevier Inc. All rights reserved.
Piper, D.Z.; Isaacs, C.M.
1996-01-01
The concentrations of Cd, Cr, Cu, Mo, Ni, Sb, U, V, and Zn were measured in early Quaternary sediment (1.32 to 1.08 Ma) from the Oki Ridge in the Japan Sea. The elements were partitioned between a detrital fraction, composed of terrigenous and volcaniclastic aluminosilicate debris, and a marine fraction, composed of biogenic and hydrogenous debris derived from seawater. The most important factors controlling minor-element accumulation rates in the marine fraction were (1) primary productivity in the photic zone, which largely controlled the flux of particulate organic-matter-bound minor elements settling through the water column and onto the seafloor, and (2) bottom-water redox, which determined the suite of elements that accumulated directly from seawater. This marine fraction of minor elements on Oki Ridge recorded six periods of high minor-element abundance. Assuming a constant bulk sediment accumulation rate, each period lasted roughly 5,000 to 10,000 years with a 41,000-year cycle. Accumulation rates of individual elements such as Cd, Mo, and U suggest sulfate-reducing conditions were established in the bottom water during the 10,000-year periods; accumulation rates of Cr and V during the intervening periods are indicative of less reducing, denitrifying conditions. Interelement ratios, for example, Cu:Mo, V:Cr, and Sb:Mo, further reflect bottom-water instability, such that bottom-water redox actually varied from sulfate reducing to denitrifying during the periods of highest minor-element accumulation rates; it varied from denitrifying to oxidizing during the intervening periods. Sediment lithology supports these interpretations of the minor-element distributions; the sediment is finely laminated for several of the periods represented by Cd, Mo, and U maxima and weakly laminated to bioturbated for the intervening periods. The geochemistry of this sediment demonstrates the unambiguous signal of Mo, principally, but of several other minor elements as well in recording sulfate-reducing conditions in bottom water. The forcing function that altered their accumulation, that is, that altered primary productivity and bottom water redox conditions, is problematic. Currently held opinion suggests that O2 depletion was most strongly developed during glacial advances. Low sea level during such times is interpreted to have enhanced primary productivity and restricted bottom-water advection.
Beltrán, María; Sánchez-Astudillo, María; Aparicio, Ramón; García-González, Diego L
2015-02-15
The geographical traceability of virgin olive oil can be controlled by chemical species that are linked to the production area. Trace elements are among these species. The hypothesis is that the transfer of elements from the soil to the oil is subjected to minor variations and therefore this chemical information can be used for geographical traceability. In order to confirm this hypothesis, the trace elements of virgin olive oils from south-western Spain were analysed, and the same elements were determined in the corresponding olive-pomaces and soils. The differences in the concentration were studied according to cultivars and locations. Results show some coincidences in the selection of elements in soils (W, Fe, Na), olive-pomace (W, Fe, Na, Mg, Mn, Ca, Ba, Li) and olive oils (W, Fe, Mg, Mn, Ca, Ba, Li, Bi), which supports their utility in traceability. In the case of olive oils, 93% of the samples were correctly classified in their geographical origins (96% for Beas, 77% for Gibraleón, 91% for Niebla, and 100% for Sanlúcar de Guadiana). Copyright © 2014 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Jordan, B.
2016-12-01
Field-based petrologic research projects often involve multiple field seasons, with geochemical analysis of samples collected in one season informing aspects of subsequent field seasons. To simulate this approach in the Iceland Volcanology Field Camp (South Dakota School of Mines & Technology) a portable X-ray fluorescence spectrometer (pXRF) was employed to provide "laboratory analyses" in support of a course mapping project. The project was conducted in the Árnes central volcano in the Neogene plateau lava succession in the West Fjords of northwestern Iceland. The field area has a wide compositional spectrum from basalt to rhyolite, with abundant intermediates. The pXRF is particularly helpful in the study of these kinds of rocks in Iceland because lithologies can be quite similar across a wide range of compositions (often lacking diagnostic macroscopic phenocryst assemblages, and having similar groundmass characteristics). A Bruker Tracer III-SD pXRF was utilized, operating at 40 KeV and 11.2 μA with no filter. Analyses were conducted at basecamp in the evenings on relatively flat fresh surfaces, with three 30 s analyses of different spots for each sample. A basic empirical calibration was generated with six aphyric samples previously analyzed by laboratory XRF. Light elements Na, Mg, and Al were not determined directly, but were estimated based on linear or polynomial correlations with other elements or elemental ratios (K, Ca, and Sr/Y respectively) determined from a previously obtained laboratory XRF data set for this central volcano. The resulting chemical analyses (normalized to sum to 100%) provided full major and minor element compositions to be used for classification, and several trace elements (V, Sr, Y, Zr) that could potentially distinguish different lavas of similar major element composition. The approach is coarse, and has pitfalls particularly regarding porphyritic rocks, but serves the objectives of the field camp project.
ICP-AES determination of minor- and major elements in apples after microwave assisted digestion.
Juranović Cindrić, Iva; Krizman, Ivona; Zeiner, Michaela; Kampić, Štefica; Medunić, Gordana; Stingeder, Gerhard
2012-12-15
The aim of this paper was to determine the content of minor and major elements in apples by inductively coupled plasma atomic emission spectrometry (ICP-AES). Prior to ICP-AES measurement, dried apples were digested in a microwave assisted digestion system. The differences in the measured element concentrations after application of open and closed microwave system as sample preparation procedures are discussed. In whole apples, flesh and peel Ag, Al, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, Sr and Zn were analysed after optimisation and validating the analytical method using ICP-AES. The accuracy of the method determined by spiking experiments was very good (recoveries 88-115%) and the limits of detection of elements of interest were from 0.01 up to 14.7 μg g(-1). The reference ranges determined in all apple samples are 39-47 mg g(-1) for K, 9-14 mg g(-1) for Na, 3-7 mg g(-1) for Mg, 3-7 μg g(-1) for Zn, 0.7-2.8 μg g(-1) for Sr. The range of Mn in peel 4-6 μg g(-1) is higher compared to whole apple from 0.7 to 1.7 μg g(-1). Cd is found only in peel, in the concentration range of 0.4-1.1 μg g(-1). Copyright © 2012 Elsevier Ltd. All rights reserved.
Minor element partitioning and mineralogy in limpets from the Ischia CO2 vent site
NASA Astrophysics Data System (ADS)
Langer, Gerald; Sadekov, Aleksey; Nehrke, Gernot; Baggini, Cecilia; Rodolfo-Metalpa, Riccardo; Hall-Spencer, Jason; Bijma, Jelle; Elderfield, Henry
2015-04-01
Specimens of the patellogastropod limpet Patella caerulea were collected within and outside a CO2 vent site at Ischia, Italy. The shells were sectioned transversally and scanned for polymorph distribution by means of confocal Raman microscopy. Minor element to calcium ratios were measured using laser-ablation-inductively-coupled-plasma-mass-spectroscopy (LA-ICPMS). Mg/Ca, Sr/Ca, and Li/Ca ratios were determined in calcitic as well as aragonitic parts of the shells. This approach allows for investigating the effects of the polymorph and the seawater carbonate chemistry on minor element partitioning separately.
Minor Elements in Nakhlite Pyroxenes: Cr in MIL00346
NASA Technical Reports Server (NTRS)
McKay, G. A.; Schwandt, C.; Le, L.; Makishima, J.; Kurihara, T.
2006-01-01
Nakhlites are olivine-bearing clinopyroxene cumulates. Based on petrographic characteristics, they may be divided into groups that cooled at different rates and may have been formed at different depths in a single flow. The order of cooling rate from slowest to fastest is NWA998
Khan, Naeem; Choi, Ji Yeon; Nho, Eun Yeong; Jamila, Nargis; Habte, Girum; Hong, Joon Ho; Hwang, In Min; Kim, Kyong Su
2014-09-01
This study aimed at analyzing the concentrations of 23 minor and trace elements in aromatic spices by inductively coupled plasma-mass spectrometry (ICP-MS), after wet digestion by microwave system. The analytical method was validated by linearity, detection limits, precision, accuracy and recovery experiments, obtaining satisfactory values in all cases. Results indicated the presence of variable amounts of both minor and trace elements in the selected aromatic spices. Manganese was high in cinnamon (879.8 μg/g) followed by cardamom (758.1 μg/g) and clove (649.9 μg/g), strontium and zinc were high in ajwain (489.9 μg/g and 84.95 μg/g, respectively), while copper was high in mango powder (77.68 μg/g). On the whole some of the minor and essential trace elements were found to have good nutritional contribution in accordance to RDA. The levels of toxic trace elements, including As, Cd, and Pb were very low and did not found to pose any threat to consumers. Copyright © 2014 Elsevier Ltd. All rights reserved.
Space transfer vehicle concepts and requirements, volume 2, book 1
NASA Technical Reports Server (NTRS)
1991-01-01
The objective of the systems engineering task was to develop and implement an approach that would generate the required study products as defined by program directives. This product list included a set of system and subsystem requirements, a complete set of optimized trade studies and analyses resulting in a recommended system configuration, and the definition of an integrated system/technology and advanced development growth path. A primary ingredient in the approach was the TQM philosophy stressing job quality from the inception. Included throughout the Systems Engineering, Programmatics, Concepts, Flight Design, and Technology sections are data supporting the original objectives as well as supplemental information resulting from program activities. The primary result of the analyses and studies was the recommendation of a single propulsion stage Lunar Transportation System (LTS) configuration that supports several different operations scenarios with minor element changes. This concept has the potential to support two additional scenarios with complex element changes. The space based LTS concept consists of three primary configurations--Piloted, Reusable Cargo, and Expendable Cargo.
Hansen, A B; Larsen, E; Hansen, L V; Lyngsaae, M; Kunze, H
1991-12-01
During 2 days of an offshore drilling operation in the North Sea, 16 airborne dust samples from the atmosphere of the Shale Shaker House were collected onto filters. During this operation, drilling mud composed of a water slurry of barite (BaSO4) together with minor amounts of additives, among them chrome lignosulphonate and chrome lignite, was circulated between the borehole and the Shale Shaker House. The concentration of airborne dust in the atmosphere was determined and the elemental composition of the particles analysed by both PIXE (proton-induced X-ray emission) and ICP-MS (inductively coupled plasma-mass spectrometry). The total amount of dust collected varied from 0.04 to 1.41 mg m-3 with barium (Ba) as the single most abundant element. The open shale shakers turned out to be the major cause of generation of dust from the solid components of the drilling mud.
Overstreet, W.C.; Day, G.W.; Botinelly, Theodore; VanTrump, George
1987-01-01
Magnetic concentrates from 106 localities in three plutons of syenite and one pluton of shonkinite in the southern Asir were analyzed spectrographically for 31 elements to determine if anomaly-enhancement techniques would identify mineralization not disclosed by conventional geochemical sample media. Positive anomalies are lacking for all elements except vanadium. Vanadium contents as high as 0.7 percent were identified in magnetic concentrates from the syenite pluton to the southeast of Suq al Ithnayn, but magnetite is sparse. This observation indicates a need to reexamine magnetite-rich drill core for possible ore-grade tenors in vanadium from the zoned pluton at Lakathah. Experimental analyses for platinum-group metals in magnetic concentrates from layered mafic plutons at Jabal Sha'i', Jabal al Ashshar, and Hishshat al Hawi should be performed to determine whether micron-size particles of the platinum-group metals are present in mafic rocks of the Arabian Shield.
Silva, L.F.O.; Oliveira, M.L.S.; Boit, K.M.; Finkelman, R.B.
2009-01-01
The current paper presents the concentration, distribution, and modes of occurrence of trace elements of 13 coals from south Brazil. The samples were collected in the state of Santa Catarina. Chemical analyses and the high ash yields indicate that all studied coals are rich in mineral matter, with SiO2 and Al2O3 dominating as determined by inductively coupled plasma-atomic emission spectrometry (ICP-AES). Quartz is the main mineral species and is associated with minor levels of feldspars, kaolinite, hematite, and iron-rich carbonates. The contents of trace elements, including As, Pb, Cd, Ni, Cr, Mn, Be, V, U, Zn, Li, Cu, Tl, and Ni, in coals were determined. A comparison of ranges and means of elemental concentrations in Santa Catarina, Brazil, and world coals shows that the ranges of most elements in Santa Catarina coal are very close to the usual worldwide concentration ranges in coal. ?? Springer Science+Business Media B.V. 2008.
NASA Technical Reports Server (NTRS)
Barron, Andrew R. (Inventor); Hepp, Aloysius F. (Inventor); Jenkins, Phillip P. (Inventor); MacInnes, Andrew N. (Inventor)
1999-01-01
A minority carrier device includes at least one junction of at least two dissimilar materials, at least one of which is a semiconductor, and a passivating layer on at least one surface of the device. The passivating layer includes a Group 13 element and a chalcogenide component. Embodiments of the minority carrier device include, for example, laser diodes, light emitting diodes, heterojunction bipolar transistors, and solar cells.
Luquet, Gilles; Salomé, Murielle; Ziegler, Andreas; Paris, Céline; Percot, Aline; Dauphin, Yannicke
2016-11-01
During premolt, crayfish develop deposits of calcium ions, called gastroliths, in their stomach wall. The stored calcium is used for the calcification of parts of the skeleton regularly renewed for allowing growth. Structural and molecular analyses of gastroliths have been primarily performed on three crayfish species, Orconectes virilis, Procambarus clarkii, and more recently, Cherax quadricarinatus. We have performed high-resolution analyses of gastroliths from the native noble crayfish, Astacus astacus, focusing on the microstructure, the mineralogical and elemental composition and distribution in a comparative perspective. Field emission scanning electron microscopy (FESEM) and atomic force microscopy (AFM) observations showed a classical layered microstructure composed of 200-nm diameter granules aligned along fibers. These granules are themselves composed of agglomerated nanogranules of 50nm-mean diameters. Denser regions of bigger fused granules are also present. Micro-Raman spectroscopy show that if A. astacus gastroliths, similarly to the other analyzed gastroliths, are mainly composed of amorphous calcium carbonate (ACC), they are also rich in amorphous calcium phosphate (ACP). The presence of a carotenoid pigment is also observed in A. astacus gastrolith contrary to C. quadricarinatus. Energy-dispersive X-ray spectroscopy (EDX) analyses demonstrate the presence of minor elements such as Mg, Sr, Si and P. The distribution of this last element is particularly heterogeneous. X-ray absorption near edge structure spectroscopy (XANES) reveals an alternation of layers more or less rich in phosphorus evidenced in the mineral phase as well as in the organic matrix in different molecular forms. Putative functions of the different P-comprising molecules are discussed. Copyright © 2016 Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Shuxia, ZHAO; Lei, ZHANG; Jiajia, HOU; Yang, ZHAO; Wangbao, YIN; Weiguang, MA; Lei, DONG; Liantuan, XIAO; Suotang, JIA
2018-03-01
The chemical composition of alloys directly determines their mechanical behaviors and application fields. Accurate and rapid analysis of both major and minor elements in alloys plays a key role in metallurgy quality control and material classification processes. A quantitative calibration-free laser-induced breakdown spectroscopy (CF-LIBS) analysis method, which carries out combined correction of plasma temperature and spectral intensity by using a second-order iterative algorithm and two boundary standard samples, is proposed to realize accurate composition measurements. Experimental results show that, compared to conventional CF-LIBS analysis, the relative errors for major elements Cu and Zn and minor element Pb in the copper-lead alloys has been reduced from 12%, 26% and 32% to 1.8%, 2.7% and 13.4%, respectively. The measurement accuracy for all elements has been improved substantially.
New chemical determinations of zinc in basalts, and rocks of similar composition
Rader, L.F.; Swadley, W.C.; Huffman, C.; Lipp, H.H.
1963-01-01
New determinations of zinc in 124 basalts by the chemical method described (Huff-Man et al. 1963) are reported. Average zinc values, in per cent, for basalts from diverse regions are as follows: Idaho, 28 samples, 0.013; Hawaii, 33 samples, 0.010; Connecticut, 27 samples, 0.0090; Oregon, 17 samples, 0.0081; California, 8 samples, 0.0071; and New Mexico, 11 samples, 0.0086; average, all samples, 0.0099 per cent zinc. A plot of differentiation indicator ratios calculated from the conventional rock analyses, CaO/(Na2O + K2O) as the ordinate and SiO2/MgO as the abscissa, was used to select, from different localities, samples essentially the same in chemical composition that were to be used for comparisons of zinc and other minor elements. Zinc correlates with MnO and with total iron as FeO. An inverse relationship found for zinc and manganese is related to the total iron content of the basalts. Thus for a given iron concentration as zinc increases, manganese decreases and vice versa. Ratios of zinc, the common denominator, to 11 other minor elements determined spectro-graphically show correlations with cobalt, gallium, scandium, yttrium, and zirconium. ?? 1963.
Disentangling controls on element impurities of bivalve shells
NASA Astrophysics Data System (ADS)
Zhao, Liqiang; Schöne, Bernd R.; Mertz-Kraus, Regina
2017-04-01
Trace and minor elements of bivalve shells can potentially serve as proxies of past environmental change. However, retrieving environmental information from element impurities of bivalve shells remains an extremely challenging task. A central difficulty concerns the fact that extrinsic and intrinsic factors governing the element incorporation are poorly constrained. Within the framework of the ARAMACC project, we aim to decipher the complexity of the incorporation of trace and minor elements into bivalve shells and explore their full potential as proxies of environmental change. More specifically, the following questions were tackled. (1) How are trace and minor elements transported from the ambient environment to the calcifying front? (2) How is their incorporation into the shells affected by environmental and physiological variables? Our findings lend support to the general assumption that divalent ions (e.g., Cu2+, Mn2+, Zn2+ and Pb2+) share the same transport pathways as Ca2+ because of similar ionic radii and electrochemical properties. However, results obtained for Mg2+, Sr2+ and Ba2+ are particularly interesting as they are at odds with existing hypotheses on the incorporation of these three elements, i.e., intracellular Ca2+ pathways (via Ca2+ channels and Ca2+-ATPase) are likely not responsible for their incorporation. Despite the existence of strong physiological interference, some encouraging results were found, in particular (1) strong, positive relationships between the Sr, Ba and Mn contents of the shells and concentrations in the ambient water, (2) only minor effects of growth rate (which is closely linked to the rate of crystal growth and hence, kinetics) on the amounts of Na, Sr, Ba and Mn incorporation into the shells. Overall, our findings demonstrate that environmental and physiological controls on the element incorporation do not have to be mutually exclusive, i.e., if environmental changes outweigh physiological influences, one could still expect that trace and minor elements of bivalve shells serve as promising environmental proxies.
The 'North American shale composite' - Its compilation, major and trace element characteristics
NASA Technical Reports Server (NTRS)
Gromet, L. P.; Dymek, R. F.; Haskin, L. A.; Korotev, R. L.
1984-01-01
North American shale composite (NASC) major element composition and compilation are presented, together with rare earth element (REE) redeterminations obtained by high precision analytical methods. The major element composition of the NASC compares closely with other average shale compositions, and significant portions of the REE and some other trace elements are contained in minor phases. The uneven REE distribution in NASC powder appears to yield the heterogeneity in analyzed aliquants. REE distributions of detrital sediments may to some extent be dependent on their minor mineral assemblages and the sedimentological factors controlling these assemblages.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chabert, C.; Coquelet-Pascal, C.; Saturnin, A.
Studies have been performed to assess the industrial perspectives of partitioning and transmutation of long-lived elements. These studies were carried out in tight connection with GEN-IV systems development. The results include the technical and economic evaluation of fuel cycle scenarios along with different options for optimizing the processes between the minor actinide transmutation in fast neutron reactors, their interim storage and geological disposal of ultimate waste. The results are analysed through several criteria (impacts on waste, on waste repository, on fuel cycle plants, on radiological exposure of workers, on costs and on industrial risks). These scenario evaluations take place inmore » the French context which considers the deployment of the first Sodium-cooled Fast Reactor (SFR) in 2040. 3 management options of minor actinides have been studied: no transmutation, transmutation in SFR and transmutation in an accelerator-driven system (ADS). Concerning economics the study shows that the cost overrun related to the transmutation process could vary between 5 to 9% in SFR and 26 % in the case of ADS.« less
NASA Astrophysics Data System (ADS)
Iveson, A. A.; Webster, J. D.; Rowe, M. C.; Neill, O. K.
2016-12-01
New experimental data for crystal-melt partitioning behaviour of a suite of trace-elements are presented. Hydrous rhyo-dacitic starting glasses from Mt. Usu, Japan, were doped with Li, Sc, Cr, Mn, Ni, Cu, Zn, Ga, Rb, Sr, Y, Nb, Mo, Ba, W, and Pb. Aqueous solutions were added such that the volatile phase(s) coexisting with amphibole, plagioclase, and clinopyroxene at run conditions buffered the S, F, and Cl contents of the melts. Internally-heated pressure vessel experiments were conducted at 750-850 °C, 1.0-4.0 Kbar, and ƒO2 ≈ NNO-NNO+2 log units. Major- and minor-element concentrations in the phenocrysts and glasses were analysed by EPMA, and trace-element contents by SIMS and/or LA-ICP-MS. The long run durations, homogeneous glasses, and minimal compositional zonation of crystals suggest that near-equilibrium conditions were achieved. Results of multiple phenocryst and glass analyses show that Nernst-type crystal-melt partition coefficients for these elements range from strongly incompatible e.g. Dmineral/melt ≈ 0 for Nb into plagioclase, to moderately incompatible e.g. Dmineral/melt ≈ 0.75 for Ga into amphibole, to strongly compatible e.g. Dmineral/melt > 50 for Ni into amphibole and clinopyroxene. Furthermore, unlike other elements investigated, partitioning of Li between phenocrysts and melt is similar for all three phases, with average DLicpx/melt ≈ 0.26 > DLiplag/melt ≈ 0.24 > DLiamph/melt ≈ 0.19. Relative to major-element composition of crystalline phases, the temperature, pressure, and ƒO2 conditions do not appear to strongly affect this behaviour. The incorporation of F and Cl into amphiboles is also consistent with the Fe-F and Mg-Cl crystallographic avoidance principles. Importantly, across two orders of magnitude in concentration, partitioning behaviours of all analysed trace-elements appear to obey Henry's Law. The experimental data are integrated with new amphibole, plagioclase, and pyroxene analyses from eruptive products of Augustine and Mt. St. Helens volcanoes. The results are applicable to understanding processes governing melt evolution during shallow magma storage and formation of economic metal deposits, where the crystallisation of porphyry-type magmas leads to fluid exsolution, and enrichment and transport of such trace- and ore-elements.
NASA Astrophysics Data System (ADS)
Randazzo, L. A.; Censi, P.; Saiano, F.; Zuddas, P.; Aricò, P.; Mazzola, S.
2009-04-01
Distributions and concentrations of many minor and trace elements in epicontinental basins, as Mediterranean Sea, are mainly driven to atmospheric fallout from surroundings. This mechanism supplies an estimated yearly flux of about 1000 kg km-2 of terrigenous matter of different nature on the whole Mediterranean basin. Dissolution of these materials and processes occurring at solid-liquid interface along the water column drive the distributions of many trace elements as V, Cr, Mn, Co, Cu, and Pb with contents ranging from pmol l-1 (Co, Cd, Pb) to nmol l-1 scale in Mediterranean seawater, with some local differences in the basin. The unwinding of an oceanographic cruise in the coastal waters of Ionian Sea during the Etna's eruptive activity in summer 2001 led to the almost unique chance to test the effects of large delivery of volcanic ash to a coastal sea water system through the analyses of distribution of selected trace elements along several seawater columns. The collection of these waters and their analyses about V, Cr, Mn, Co, Cu, and Pb contents evidenced trace element concentrations were always higher (about 1 order of magnitude at least) than those measured concentrations in the recent past in Mediterranean seawater, apart from Pb. Progressive increase of concentrations of some elements with depth, sometimes changing in a "conservative" behaviour without any clear reason and the observed higher concentrations required an investigation about interaction processes occurring at solid-liquid interface between volcanic ash and seawater along water columns. This investigation involving kinetic evaluation of trace element leaching to seawater, was carried out during a 6 months time period under laboratory conditions. X-ray investigations, SEM-EDS observations and analyses on freshly-erupted volcanic ash evidenced formation of alteration clay minerals onto glass fraction surfaces. Chemical analyses carried out on coexisting liquid phase demonstrated that trace element leaching occurs through a first quick followed by a slow second step that attaints to an apparent equilibrium after 6 months. Amplitude of kinetic rate constant measured for SiO2 release during the first step and behaviour of Ti/Si and Cr/Si rations in primary volcanic minerals, glass fraction and leaching solutions during the first 1 month stage of the experimental interaction allowed to demonstrate that trace element release mainly occurs from glassy materials and Ti-rich magnetite.
NASA Astrophysics Data System (ADS)
Buchanan, A.; Hanchar, J. M.; Steele-MacInnis, M. J.; Crowley, J. L.; Valley, P. M.; Fisher, C. M.; Fedo, C.; Piccoli, P. M.; Fournelle, J.
2012-12-01
The Lyon Mountain granite (LMG) is located in the northeastern Adirondack Mountains in New York State and hosts several low-titanium iron oxide apatite (IOA) ore deposits. The ores are predominately hosted by perthite bearing granite, which has been extensively altered to albite and microcline granite by Na and K metasomatism. This alteration results in several distinct groups of rocks that are dominated by either K or Na addition and a group composed of mixed Na and K addition. The different groups of altered perthite also lie on a trend suggestive of addition of Fe to each, consistent with a secondary mineralization origin. Previous work showed that the host rocks of the IOA ores have zircon with ~1150 Ma cores and 1060-1050 Ma rims and whole grains. This study aims to further constrain the timing of LMG emplacement, subsequent hydrothermal alteration, and Fe mineralization through geochemical analysis of the major, minor, and accessory phases and geochronology of accessory phases. SIMS analyses of zircon from several of the IOA ores reveal at least two periods of growth after LMG magmatism, at 1039 +/- 4.4 Ma and 1016 +/- 7 Ma to 1000 +/- 9 Ma. In situ EMPA and LA-ICPMS trace element analyses of the zircon rims and cores reveal that in two samples the zircon rims are enriched in rare earth elements (REE) compared to their cores, potentially pointing to a hydrothermal origin. Apatite has unusually high REE and Y concentrations (some total REE2O3 > 20 wt. % oxide and up to 8 wt. % oxide Y2O3), as does titanite, which allowed for the in situ analysis of Sm-Nd in apatite and titanite by LA-MC-ICP-MS. Initial Nd isotopic composition of both ore and host rock apatite and host rock titanite are consistent with published Adirondack initial Nd whole rock data, suggesting a local source for REE in these ores. EMPA and LA-ICPMS trace-element analyses of the major rock-forming minerals indicate that the feldspar have undergone Na-metasomatism and are depleted in REEs, perhaps signifying the "local source" and the mechanism of the REE enrichment in the LMG apatite in the IOA ores and host rocks. In contrast, the minor- and trace-element compositions of the other major rock-forming minerals (e.g., clinopyroxene and fayalite) as well as the zircon, and fluorite in the LMG have average igneous granitic trace- and minor-element compositions. To better understand the timing and origin of these post ~1050 Ma events, U-Pb ID-TIMS dating of apatite and titanite, and in situ LA-MC-ICPMS Sm-Nd analysis were done on the ore and host rock samples. Apatite dates range from 1050 to 850 Ma and titanite dates range from ~1015 to 970 Ma. There is significant age variation within samples and within grains. Titanite does not have sufficient spread for accurate Sm-Nd isochron dating and two ore-apatite samples have homogenous initial Nd isotopic and Sm-Nd elemental ratios, precluding calculation of Sm-Nd dates. A third ore sample shows a large spread in Sm-Nd and yields a Sm-Nd isochron date of ~850 Ma, in close agreement with U-Pb apatite dates. The Sm-Nd isochron and U-Pb apatite dates may reflect cooling recorded in these minerals or a younger hydrothermal mineralization event.
Environmental assessment of Al-Hammar Marsh, Southern Iraq.
Al-Gburi, Hind Fadhil Abdullah; Al-Tawash, Balsam Salim; Al-Lafta, Hadi Salim
2017-02-01
(a) To determine the spatial distributions and levels of major and minor elements, as well as heavy metals, in water, sediment, and biota (plant and fish) in Al-Hammar Marsh, southern Iraq, and ultimately to supply more comprehensive information for policy-makers to manage the contaminants input into the marsh so that their concentrations do not reach toxic levels. (b) to characterize the seasonal changes in the marsh surface water quality. (c) to address the potential environmental risk of these elements by comparison with the historical levels and global quality guidelines (i.e., World Health Organization (WHO) standard limits). (d) to define the sources of these elements (i.e., natural and/or anthropogenic) using combined multivariate statistical techniques such as Principal Component Analysis (PCA) and Agglomerative Hierarchical Cluster Analysis (AHCA) along with pollution analysis (i.e., enrichment factor analysis). Water, sediment, plant, and fish samples were collected from the marsh, and analyzed for major and minor ions, as well as heavy metals, and then compared to historical levels and global quality guidelines (WHO guidelines). Then, multivariate statistical techniques, such as PCA and AHCA, were used to determine the element sourcing. Water analyses revealed unacceptable values for almost all physio-chemical and biological properties, according to WHO standard limits for drinking water. Almost all major ions and heavy metal concentrations in water showed a distinct decreasing trend at the marsh outlet station compared to other stations. In general, major and minor ions, as well as heavy metals exhibit higher concentrations in winter than in summer. Sediment analyses using multivariate statistical techniques revealed that Mg, Fe, S, P, V, Zn, As, Se, Mo, Co, Ni, Cu, Sr, Br, Cd, Ca, N, Mn, Cr, and Pb were derived from anthropogenic sources, while Al, Si, Ti, K, and Zr were primarily derived from natural sources. Enrichment factor analysis gave results compatible with multivariate statistical techniques findings. Analysis of heavy metals in plant samples revealed that there is no pollution in plants in Al-Hammar Marsh. However, the concentrations of heavy metals in fish samples showed that all samples were contaminated by Pb, Mn, and Ni, while some samples were contaminated by Pb, Mn, and Ni. Decreasing of Tigris and Euphrates discharges during the past decades due to drought conditions and upstream damming, as well as the increasing stress of wastewater effluents from anthropogenic activities, led to degradation of the downstream Al-Hammar Marsh water quality in terms of physical, chemical, and biological properties. As such properties were found to consistently exceed the historical and global quality objectives. However, element concentration decreasing trend at the marsh outlet station compared to other stations indicate that the marsh plays an important role as a natural filtration and bioremediation system. Higher element concentrations in winter were due to runoff from the washing of the surrounding Sabkha during flooding by winter rainstorms. Finally, the high concentrations of heavy metals in fish samples can be attributed to bioaccumulation and biomagnification processes.
NASA Technical Reports Server (NTRS)
Papike, J. J.; Karner, J. M.; Shearer, C. K.; Spilde, M. N.
2002-01-01
Spinels from Apollo 12 Olivine basalts have been studied by Electron and Ion microprobe techniques. The zoning trends of major, minor and trace elements provide new insights into the conditions under which planetary basalts form. Additional information is contained in the original extended abstract.
Understanding gas shales using inorganic, ternary geochemical systematics.
NASA Astrophysics Data System (ADS)
Basu, Sudeshna; Jones, Adrian; Verchovsky, Alexander
2016-04-01
We have developed a new approach of simultaneous analyses of carbon, nitrogen and noble gases, for isotopic and elemental compositions in bulk shales from different depths (11785 to 11909 feet) of a core from the Haynesville Bossier formation to decouple the different trapped components. This is preceded by major, minor and trace elemental analyses to understand their paleo productivity, tectonic and redox conditions of deposition as well as constraining their alteration and weathering. 5 to 10 mg of samples have been combusted from 200-1200°C in incremental steps of 100°C. Based on δ13C, we identify both marine+lacustrine (δ13C ~ -25 ‰, C/N ~ 5) and minor continental organic matter (δ13C ~ -27 ‰, C/N ~ 60) in the samples, in agreement with observations from elemental compositions. Extremely depleted δ13C of ≤ -34 ‰ in some temperature steps, can be attributed to methanogenesis. Two carbonate populations, primary (δ13C ~ 0 to 2 ‰) and diagenetic (δ13C ~ -13 to -11 ‰) can also be identified. We have been able to identify the multiple C components present in the samples, including very minor ones, without resorting to acid treatment. The bulk N δ15N values vary from -1.2to +6.4 ‰, but show a wide range from -15 to 15 ‰ within individual steps. By suitable modelling, we constrain the primary δ15N to be 5 to 8 ‰, identifiable in very high temperature steps of heating. This is possible if there is penetration of hot fluids that eliminates organic N along a reaction front leaving it fractionated, but leaves behind an unreacted core of residual nitrogen unaffected by isotopic fractionation (Boudou et al., 2008). Our study indicates that using bulk N values as primary signatures to constrain the redox conditions of deposition or thermal maturity of shales as is the practice, should be done with caution. Simultaneously obtained noble gases were used to constrain gas retention in the samples. Deviations of measured 4He/40Ar* (where 40Ar* represents radiogenic 40Ar after correcting for contribution from atmospheric Ar) from expected values has been used to monitor gas loss by degassing. Boudou, J., Schimmelmann, A., Ader, M., Mastalerz, M., Sebilo, M., Gengembre, L.,2008. Organic nitrogen chemistry during low grade metamorphism. Geochimica Cosmochimica Acta 72, 1199-1221.
NASA Astrophysics Data System (ADS)
Omar, Aimi Farehah; Ismail, Ismanizan
2016-11-01
Sesquiterpene synthase (SS) catalyzes the formation of sesquiterpenes from farnesyl diphosphate (FDP) via carbocation intermediates. In this study, the promoter region of sesquiterpene synthase was isolated from Persicaria minor to identify possible cis-acting elements in the promoter. The full-length PmSS promoter of P. minor is 1824-bp sequences. The sequence was analyzed and several putative cis-acting regulatory elements were identified. Three cis-acting regulatory elements were selected for deletion analysis which are cis-acting element involved in wound responsiveness (WUN), cis - acting element involved in defense and stress responsiveness (TC) and cis-acting element involved in ABA responsiveness (ABRE). Series of deletions were conducted to assess the promoter activity producing three truncated fragments promoter; Prom 2 1606-bp, Prom 3 1144- bp, and Prom 4 921-bp. The full-length promoter and its deletion series were cloned into the pBGWFS7 vector which contain β-glucuronidase (GUS) gene and green fluorescent protein (GFP) as the reporter gene. All constructs were successfully transformed into Arabidopsis thaliana based on PCR of positive BASTA resistance plants.
Origins and Distribution of Chondritic Olivine Inferred from Wild 2 and Chondrite Matrix
NASA Technical Reports Server (NTRS)
Frank, D. R.; Zolensky, M. E.
2014-01-01
To date, only 180 particle impact tracks from Wild 2 have been extracted from the Stardust aerogel collector and even fewer have been thoroughly characterized. In order to provide a cohesive compositional dataset that can be compared to the meteorite record, we have made both major and minor element analyses (TEM/EDXS) of olivine and low-Ca pyroxene for 39 particles harvested from 26 tracks. However, the dearth of equivalent analyses for these phases in chondrite matrix hinders their comparison to the Wild 2 samples. To properly permit comparison of chondritic olivine and pyroxene to the Wild 2 samples, we have also provided a large, comprehensive EPMA dataset (greater than10(exp 3) analyses) of analogous grains (5-30 micrometers) isolated in L/LL3.0-4, CI, CM, CR, CH, CO, CV, Acfer 094, EH3, EL6, and Kakangari matrix
The BCLA Minor: Business, Communication, and Liberal Arts Minor at Towson University
ERIC Educational Resources Information Center
Mahin, Linda
2008-01-01
In this article, the author describes a cross-disciplinary minor that combines elements of business, communication, and the liberal arts. The BCLA Minor enhances employment opportunities and cultural awareness for students with majors in the Colleges of Business and Economics, Fine Arts and Communication, and Liberal Arts by integrating the…
Publications - RDF 2005-5 | Alaska Division of Geological & Geophysical
content DGGS RDF 2005-5 Publication Details Title: Major-oxide, minor-oxide, and trace-element geochemical ., and Lessard, R.R., 2005, Major-oxide, minor-oxide, and trace-element geochemical data from rocks ; Zinc; Zirconium Top of Page Department of Natural Resources, Division of Geological & Geophysical
PIXE analysis of ancient Chinese Qing dynasty porcelain
NASA Astrophysics Data System (ADS)
Cheng, Huansheng; He, Wenquan; Tang, Jiayong; Yang, Fujia; Wang, Jianhua
1996-09-01
The major and minor chemical compositions and trace element content of white glaze made in Qing dynasty at kuan kiln have been determined by PIXE. Experimental results show that trace element contents RbSrZr are useful to distinguish the place of production of ancient porcelain. In the porcelain from different kilns situated in a same province, the trace element contents can be different from each other. Determining and comparing the major and minor compositions and trace elemental concentrations in white glaze by PIXE technique, we can distinguish a precious Qing dynasty porcelain made at kuan kiln from a fake.
Holocene geochemical footprint from Semi-arid alpine wetlands in southern Spain
NASA Astrophysics Data System (ADS)
García-Alix, Antonio; Jiménez-Espejo, Francisco J.; Jiménez-Moreno, Gonzalo; Toney, Jaime L.; Ramos-Román, María J.; Camuera, Jon; Anderson, R. Scott; Delgado-Huertas, Antonio; Martínez-Ruiz, Francisca; Queralt, Ignasi
2018-02-01
Here we provide the geochemical dataset that our research group has collected after 10 years of investigation in the Sierra Nevada National Park in southern Spain. These data come from Holocene sedimentary records from four alpine sites (ranging from ˜2500 to ˜3000 masl): two peatlands and two shallow lakes. Different kinds of organic and inorganic analyses have been conducted. The organic matter in the bulk sediment was characterised using elemental measurements and isotope-ratio mass spectrometry (EA-IRMS). Leaf waxes in the sediment were investigated by means of chromatography with flame-ionization detection and mass spectrometry (GC-FID, GC-MS). Major, minor and trace elements of the sediments were analysed with atomic absorption (AAS), inductively coupled plasma mass spectrometry (ICP-MS), as well as X-ray scanning fluorescence. These data can be reused by environmental researchers and soil and land managers of the Sierra Nevada National Park and similar regions to identify the effect of natural climate change, overprinted by human impact, as well as to project new management policies in similar protected areas.
Knott, J.R.; Sarna-Wojcicki, A. M.; Montanez, I.P.; Wan, E.
2007-01-01
Volcanic glass samples from the same volcanic center (intra-source) often have a similar major-element composition. Thus, it can be difficult to distinguish between individual tephra layers, particularly when using similarity coefficients calculated from electron microprobe major-element measurements. Minor/trace element concentrations in glass can be determined by solution inductively coupled plasma mass spectrometry (S-ICP-MS), but have not been shown as suitable for use in large tephrochronologic databases. Here, we present minor/trace-element concentrations measured by S-ICP-MS and compare these data by similarity coefficients, the method commonly used in large databases. Trial samples from the Bishop Tuff, the upper and lower tuffs of Glass Mountain and the tuffs of Mesquite Spring suites from eastern California, USA, which have an indistinguishable major-element composition, were analyzed using S-ICP-MS. The resulting minor/trace element similarity coefficients clearly separated the suites of tephra layers and, in most cases, individual tephra layers within each suite. Comparisons with previous instrumental neutron activation analysis (INAA) elemental measurements were marginally successful. This is important step toward quantitative correlation in large tephrochronologic databases to achieve definitive identification of volcanic glass samples and for high-resolution age determinations. ?? 2007 Elsevier Ltd and INQUA.
Study of ephemeris accuracy of the minor planets. [using computer based data systems
NASA Technical Reports Server (NTRS)
Brooks, D. R.; Cunningham, L. E.
1974-01-01
The current state of minor planet ephemerides was assessed, and the means for providing and updating these emphemerides for use by both the mission planner and the astronomer were developed. A system of obtaining data for all the numbered minor planets was planned, and computer programs for its initial mechanization were developed. The computer based system furnishes the osculating elements for all of the numbered minor planets at an adopted date of October 10, 1972, and at every 400 day interval over the years of interest. It also furnishes the perturbations in the rectangular coordinates relative to the osculating elements at every 4 day interval. Another computer program was designed and developed to integrate the perturbed motion of a group of 50 minor planets simultaneously. Sampled data resulting from the operation of the computer based systems are presented.
Genesis of Augite-Bearing Ureilites: Evidence From LA-ICP-MS Analyses of Pyroxenes and Olivine
NASA Technical Reports Server (NTRS)
Herrin, J. S.; Lee, C-T. A.; Mittlefehldt, D. W.
2008-01-01
Ureilites are ultramafic achondrites composed primarily of coarse-grained low-Ca pyroxene and olivine with interstitial carbonaceous material, but a number of them contain augite [1]. Ureilites are considered to be restites after partial melting of a chondritic precursor, although at least some augite-bearing ureilites may be partially cumulate [1, 2]. In this scenario, the augite is a cumulus phase derived from a melt that infiltrated a restite composed of typical ureilite material (olivine+low-Ca pyroxene) [2]. To test this hypothesis, we examined the major and trace element compositions of silicate minerals in select augite-bearing ureilites with differing mg#. Polished thick sections of the augite-bearing ureilites ALH 84136 , EET 87511, EET 96293, LEW 88201, and META78008 and augite-free typical ureilite EET 90019 were examined by EPMA for major and minor elements and laser ablation ICP-MS (LA-ICP-MS) for trace elements, REE in particular. Although EET 87511 is reported to contain augite, the polished section that we obtained did not.
Mesh Deformation Based on Fully Stressed Design: The Method and Two-Dimensional Examples
NASA Technical Reports Server (NTRS)
Hsu, Su-Yuen; Chang, Chau-Lyan
2007-01-01
Mesh deformation in response to redefined boundary geometry is a frequently encountered task in shape optimization and analysis of fluid-structure interaction. We propose a simple and concise method for deforming meshes defined with three-node triangular or four-node tetrahedral elements. The mesh deformation method is suitable for large boundary movement. The approach requires two consecutive linear elastic finite-element analyses of an isotropic continuum using a prescribed displacement at the mesh boundaries. The first analysis is performed with homogeneous elastic property and the second with inhomogeneous elastic property. The fully stressed design is employed with a vanishing Poisson s ratio and a proposed form of equivalent strain (modified Tresca equivalent strain) to calculate, from the strain result of the first analysis, the element-specific Young s modulus for the second analysis. The theoretical aspect of the proposed method, its convenient numerical implementation using a typical linear elastic finite-element code in conjunction with very minor extra coding for data processing, and results for examples of large deformation of two-dimensional meshes are presented in this paper. KEY WORDS: Mesh deformation, shape optimization, fluid-structure interaction, fully stressed design, finite-element analysis, linear elasticity, strain failure, equivalent strain, Tresca failure criterion
Gázquez, M J; Bolívar, J P; García-Tenorio, R; Vaca, F
2009-07-30
The present study was conducted to characterize several raw materials and co-products from the titanium dioxide industry in relation to their elemental composition (major, minor and trace elements), granulometry, mineralogy, microscopic morphology and physical composition. The main objective was to gain basic information for the future potential application of these co-products in fields such as agriculture, construction, civil engineering, etc. Microscopic studies were performed by applying scanning electron microscopy with X-ray microanalysis (SEM-XRMA) while the mineralogical compositions were analysed by means of the X-ray diffraction (XRD) technique. The concentrations of major elements such as Na, Al, Si, Ca, Ti, Fe, S and K were determined by X-ray fluorescence (XRF), while heavy metals and other trace elements were determined by ICP-MS. The physicochemical characterization of the raw materials used in the titanium dioxide industry, in addition to the characterization of the co-products generated, has enabled the evaluation of the degree of fractionation of different elements and compounds between the different co-products, as well as the control of the possible variations in the physicochemical composition of the raw materials throughout the time and the study of the influence of these variations in the characteristics of the obtained co-products. As a main conclusion of our study, it is possible to indicate that the levels of the pollutant elements associated to the co-products analysed were, in general, within safe limits and, therefore, they could potentially be used in composites as fertilizers or for building materials in road construction, etc. Nevertheless, for the specific application of each of these co-products in agriculture, construction and civil engineering, additional studies need to be performed to evaluate their appropriateness for the proposed application, together with specific studies on their health and environmental impact.
Trace element analysis by EPMA in geosciences: detection limit, precision and accuracy
NASA Astrophysics Data System (ADS)
Batanova, V. G.; Sobolev, A. V.; Magnin, V.
2018-01-01
Use of the electron probe microanalyser (EPMA) for trace element analysis has increased over the last decade, mainly because of improved stability of spectrometers and the electron column when operated at high probe current; development of new large-area crystal monochromators and ultra-high count rate spectrometers; full integration of energy-dispersive / wavelength-dispersive X-ray spectrometry (EDS/WDS) signals; and the development of powerful software packages. For phases that are stable under a dense electron beam, the detection limit and precision can be decreased to the ppm level by using high acceleration voltage and beam current combined with long counting time. Data on 10 elements (Na, Al, P, Ca, Ti, Cr, Mn, Co, Ni, Zn) in olivine obtained on a JEOL JXA-8230 microprobe with tungsten filament show that the detection limit decreases proportionally to the square root of counting time and probe current. For all elements equal or heavier than phosphorus (Z = 15), the detection limit decreases with increasing accelerating voltage. The analytical precision for minor and trace elements analysed in olivine at 25 kV accelerating voltage and 900 nA beam current is 4 - 18 ppm (2 standard deviations of repeated measurements of the olivine reference sample) and is similar to the detection limit of corresponding elements. To analyse trace elements accurately requires careful estimation of background, and consideration of sample damage under the beam and secondary fluorescence from phase boundaries. The development and use of matrix reference samples with well-characterised trace elements of interest is important for monitoring and improving of the accuracy. An evaluation of the accuracy of trace element analyses in olivine has been made by comparing EPMA data for new reference samples with data obtained by different in-situ and bulk analytical methods in six different laboratories worldwide. For all elements, the measured concentrations in the olivine reference sample were found to be identical (within internal precision) to reference values, suggesting that achieved precision and accuracy are similar. The spatial resolution of EPMA in a silicate matrix, even at very extreme conditions (accelerating voltage 25 kV), does not exceed 7 - 8 μm and thus is still better than laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) or secondary ion mass spectrometry (SIMS) of similar precision. These make the electron microprobe an indispensable method with applications in experimental petrology, geochemistry and cosmochemistry.
NASA Astrophysics Data System (ADS)
Paquette, J.; Deakin, M.; Baker, D. R.
2006-12-01
Because in situ observations of actively growing surfaces are technically impractical, our understanding of crystal growth mechanisms at hydrothermal and magmatic conditions lags behind that of minerals that can be grown from aqueous solutions at or near room temperature. Growing silicate minerals from hydrous synthetic carbonate melts offers the opportunity to relate directly minor element incorporation to their surface microtopography. Natural hydrothermal diopside was used to seed experiments in which synthetic clinopyroxene crystals were grown at 800 degrees C and 10 kbars for 24 hours, from alkaline melts modelled after the lavas of the Tanzanian volcano Oldoinyo Lengai. The melts were prepared from Na2CO3, K2CO3, CaCO3, MgCO3 and Fe3O4 reagents. One run was anhydrous and the others contained either 2.5 or 5 wt. % H2O. Euhedral tabular crystals ranging in size from 100 to 300 ìm across were found in all three runs, hand-picked and freed from their carbonate matrix by overnight immersion in dilute acetic acid. The crystals consist of \\{110\\} prism, \\{100\\} and \\{001\\} pinacoids and a \\{111\\} dipyramid. AFM images resolved a distinct surface microtopography on each form: arrays of broad macrosteps on \\{100\\}, lens- shaped islands on \\{001\\} facets and striated fiber-like crystallites on \\{110\\}. EMP analyses of polished grain mounts show that compositional zoning of Na and Fe occurs not only among non-equivalent growth sectors but also within single \\{100\\} sectors. Electron microprobe maps of sequentially polished sections indicate that zoning within \\{100\\} sectors reflects differential uptake of Na and Fe on symmetrically non-equivalent steps. Near the crystal surface, the non- equivalent coeval vicinal faces of growth hillocks on \\{100\\} are either diopside-like, Na.007Ca1.00(Mg0.754Fe2+0.22Mn2+0.013Al_{0.003)Si2.00O6 , or acmitic, Ca0.63Na0.35(Mg0.64Fe3+ 0.36)Al0.01Si1.99O6 in composition. Step-specific incorporation of minor elements in a clinopyroxene face has only been documented once, in a hydrothermal diopside from Orford (Quebec), where Fe(II) and Mn(II) were differentially incorporated on steps oriented parallel to [010] on \\{100\\} faces. This natural example and our synthetic crystals reflect growth regimes where minor element incorporation was limited by surface-structural kinetics rather than diffusion- controlled kinetics. Such step-specific surface-structural control has never been reported in clinopyroxenes grown from silicate melts. Is it present, but more subtle, or do silicate melts promote a significantly different growth regime? Comparing zoning patterns in synthetic silicates grown from carbonate versus silicate melts could put new constraints on current models of element partitioning.
7 CFR 1753.80 - Minor construction procedure.
Code of Federal Regulations, 2010 CFR
2010-01-01
... same calendar year is limited to the following amounts for the following discrete categories of minor...) A single minor construction project may be a discrete element of a somewhat larger overall project... placement project. It cannot be a portion, by dividing into smaller segments, of a discrete major...
Fragments of ancient lunar crust: Ferroan noritic anorthosites from the descartes region of the Moon
NASA Technical Reports Server (NTRS)
Norman, M. D.; Alibert, C.; Mcculloch, M. T.
1993-01-01
Noritic anorthosite clasts from breccia 67016 have bulk compositions similar to that of the upper crust of the Moon and petrogenetic affinities with pristine ferroan anorthosites. Rb-Sr and Sm-Nd isotopic compositions of mineral separates from one of these clasts suggest very old (greater than or = 4.4 Ga) ages, but interpretation of these data is complicated by the multi-stage history of the clasts which involved magmatic crystallization, brecciation, subsolidus recrystallization, and sulfide metasomatism. These clasts record some of the earliest events on the Moon, including early crust formation, accretionary bombardment, and degassing of the lunar interior. Modal analyses of these clasts show they are now composed of about 70 percent plagioclase, 28 percent pyroxene, 2 percent troilite, and minor amounts of ilmenite and chromite. No metallic iron, phosphates, or other trace phases were observed. Olivine is very rare, occurring only as relicts within secondary troilite+pyroxene intergrowths which may reflect reaction of olivine with sulfurous vapors. PIXE proton microprobe analyses of the sulfides show that the metasomatism was accompanied by enrichments of Cu, Zn, Ni, Se, and Sb. The clasts have been only mildly shocked since the observed texture was established. Major and minor element mineral compositions are very homogeneous and strikingly similar to those of pristine ferroan anorthosites. Pyroxene compositions indicate equilibration temperatures of 850-900 C. Except for the sulfide and chalcophile element metasomatism, these clasts appear to be essentially monomict and probably represent a noritic member of the ferroan anorthosite suite. Their low Ni contents and Ni/Co ratios are consistent with the interpretation of these clasts as igneous rocks which have escaped mixing with meteoritic material.
Weathering of the New Albany Shale, Kentucky: II. Redistribution of minor and trace elements
Tuttle, M.L.W.; Breit, G.N.; Goldhaber, M.B.
2009-01-01
During weathering, elements enriched in black shale are dispersed in the environment by aqueous and mechanical transport. Here a unique evaluation of the differential release, transport, and fate of Fe and 15 trace elements during progressive weathering of the Devonian New Albany Shale in Kentucky is presented. Results of chemical analyses along a weathering profile (unweathered through progressively weathered shale to soil) describe the chemically distinct pathways of the trace elements and the rate that elements are transferred into the broader, local environment. Trace elements enriched in the unweathered shale are in massive or framboidal pyrite, minor sphalerite, CuS and NiS phases, organic matter and clay minerals. These phases are subject to varying degrees and rates of alteration along the profile. Cadmium, Co, Mn, Ni, and Zn are removed from weathered shale during sulfide-mineral oxidation and transported primarily in aqueous solution. The aqueous fluxes for these trace elements range from 0.1 g/ha/a (Cd) to 44 g/ha/a (Mn). When hydrologic and climatic conditions are favorable, solutions seep to surface exposures, evaporate, and form Fe-sulfate efflorescent salts rich in these elements. Elements that remain dissolved in the low pH (<4) streams and groundwater draining New Albany Shale watersheds become fixed by reactions that increase pH. Neutralization of the weathering solution in local streams results in elements being adsorbed and precipitated onto sediment surfaces, resulting in trace element anomalies. Other elements are strongly adsorbed or structurally bound to solid phases during weathering. Copper and U initially are concentrated in weathering solutions, but become fixed to modern plant litter in soil formed on New Albany Shale. Molybdenum, Pb, Sb, and Se are released from sulfide minerals and organic matter by oxidation and accumulate in Fe-oxyhydroxide clay coatings that concentrate in surface soil during illuviation. Chromium, Ti, and V are strongly correlated with clay abundance and considered to be in the structure of illitic clay. Illite undergoes minimal alteration during weathering and is concentrated during illuvial processes. Arsenic concentration increases across the weathering profile and is associated with the succession of secondary Fe(III) minerals that form with progressive weathering. Detrital fluxes of particle-bound trace elements range from 0.1 g/ha/a (Sb) to 8 g/ha/a (Mo). Although many of the elements are concentrated in the stream sediments, changes in pH and redox conditions along the sediment transport path could facilitate their release for aqueous transport.
NASA Technical Reports Server (NTRS)
Kimura, Makoto; El-Goresy, Ahmed; Palme, Herbert; Zinner, Ernst
1993-01-01
A comprehensive study is performed for the Ca-,Al-rich inclusions (CAIs) in the unique chondrite ALH85085. The ALH85085 inclusions are smaller (5-80 microns) and more refractory than their counterparts in carbonaceous chondrites. The study includes 42 inclusions for petrography and mineralogy, 15 for bulk major and minor element chemical composition, six for Mg-Al isotopic systematics, 10 for Ca isotopes, nine for Ti isotopes, and six for trace element abundances. In addition, oxygen-isotopic compositions were determined in minerals from a single inclusion. No correlation is found between mineralogy, major element chemistry, and trace element abundances. It is further shown that the high-temperature geochemical behavior of ultrarefractory trace elements is decoupled from that of the major elements Ca and Ti (Ti is correlated with the relatively volatile elements Nb and Yb) implying that perovskite is of only minor importance as carrier of ultrarefractories.
Batashev, Denis R.; Pakhomova, Marina V.; Razumovskaya, Anna V.; Voitsekhovskaja, Olga V.; Gamalei, Yuri V.
2013-01-01
The discovery of abundant plasmodesmata at the bundle sheath/phloem interface in Oleaceae (Gamalei, 1974) and Cucurbitaceae (Turgeon et al., 1975) raised the questions as to whether these plasmodesmata are functional in phloem loading and how widespread symplasmic loading would be. Analysis of over 800 dicot species allowed the definition of “open” and “closed” types of the minor vein phloem depending on the abundance of plasmodesmata between companion cells and bundle sheath (Gamalei, 1989, 1990). These types corresponded to potential symplasmic and apoplasmic phloem loaders, respectively; however, this definition covered a spectrum of diverse structures of phloem endings. Here, a review of detailed cytological analyses of minor veins in 320 species from the subclass Asteridae is presented, including data on companion cell types and their combinations which have not been reported previously. The percentage of Asteridae species with “open” minor vein cytology which also contain sieve-element-companion cell complexes with “closed” cytology, i.e., that show specialization for both symplasmic and apoplasmic phloem loading, was determined. Along with recent data confirming the dissimilar functional specialization of structurally different parts of minor vein phloem in the stachyose-translocating species Alonsoa meridionalis (Voitsekhovskaja et al., 2009), these findings suggest that apoplasmic loading is indispensable in a large group of species previously classified as putative symplasmic loaders. Altogether, this study provides formal classifications of companion cells and of minor veins, respectively, in 24 families of the Asteridae based on their structural features, opening the way to a close investigation of the relationship between structure and function in phloem loading. PMID:23970890
Trace elements record complex histories in diogenites
NASA Astrophysics Data System (ADS)
Balta, J. B.; Beck, A. W.; McSween, H. Y.
2012-12-01
Diogenite meteorites are cumulate rocks composed mostly of orthopyroxene and chemically linked to eucrites (basaltic) and howardites (brecciated mixtures of diogenites and eucrites). Together, they represent the largest single family of achondrite meteorites delivered to Earth, and have been spectrally linked to the asteroid 4 Vesta, the largest remaining basaltic protoplanet. However, this spectral link is non-unique as many basaltic asteroids likely formed and were destroyed in the early solar system. Recent work suggested that Vesta may be an unlikely parent body for the diogenites based on correlations between trace elements and short-lived isotope decay products, which would be unlikely to survive on a body as large as Vesta due to its long cooling history [1]. Recent analyses of terrestrial and martian olivines have demonstrated that trace element spatial distributions can preserve evidence of their crystallization history even when major elements have been homogenized [2]. We have mapped minor elements including Cr, Al, and Ti in seemingly homogeneous diogenite orthopyroxenes and found a variety of previously unobserved textures. The pyroxenes in one sample (GRA 98108) are seemingly large grains of variable shapes and sizes, but the trace elements reveal internal grain boundaries between roughly-equal sized original subgrains, with equilibrated metamorphic triple junctions between them and trace element depletions at the boundaries. These trends suggest extraction of trace elements by a magma along those relict grain boundaries during a reheating event. Two other samples show evidence of fracturing and annealing, with trace element mobility within grains. One sample appears to have remained a closed system during annealing (MET 01084), while the other has interacted with a fluid or magma to move elements along annealed cracks (LEW 88679). These relict features establish that the history of diogenite pyroxenes is more complex than their homogeneous major element compositions imply. Many trace element analyses are performed using either bulk rock techniques or spot analyses, and these maps suggest those types of analyses likely sample variable trace element abundances even within otherwise homogeneous grains, rendering their results difficult to interpret. Consequently, the correlation discussed previously between trace elements and short lived isotopes has likely been impacted by post-magmatic alteration and cannot solely be used to argue that HED's cannot be derived from Vesta. Furthermore, these maps strengthen the HED-Vesta link by suggesting that the diogenites underwent an extended history of cooling, reheating, partial melting, impact fragmentation, fluid/melt migration, and finally re-annealing. These complicated steps are particularly noteworthy as the pyroxene cumulate layer on the asteroid Vesta should lie beneath the eucritic crust, implying that early impacts were able to penetrate that crust and affect the diogenite layers early in Vesta's history, most likely while the asteroid was still hot enough to allow for annealing and regrowth of fractured grains. [1] Schiller et al. (2011) [2] Milman-Barris et al. (2008)
Preliminary Report on U-Th-Pb Isotope Systematics of the Olivine-Phyric Shergottite Tissint
NASA Technical Reports Server (NTRS)
Moriwaki, R.; Usui, T.; Yokoyama, T.; Simon, J. I.; Jones, J. H.
2014-01-01
Geochemical studies of shergottites suggest that their parental magmas reflect mixtures between at least two distinct geochemical source reservoirs, producing correlations between radiogenic isotope compositions, and trace element abundances.. These correlations have been interpreted as indicating the presence of a reduced, incompatible-element- depleted reservoir and an oxidized, incompatible-element-rich reservoir. The former is clearly a depleted mantle source, but there has been a long debate regarding the origin of the enriched reservoir. Two contrasting models have been proposed regarding the location and mixing process of the two geochemical source reservoirs: (1) assimilation of oxidized crust by mantle derived, reduced magmas, or (2) mixing of two distinct mantle reservoirs during melting. The former clearly requires the ancient martian crust to be the enriched source (crustal assimilation), whereas the latter requires a long-lived enriched mantle domain that probably originated from residual melts formed during solidification of a magma ocean (heterogeneous mantle model). This study conducts Pb isotope and U-Th-Pb concentration analyses of the olivine-phyric shergottite Tissint because U-Th-Pb isotope systematics have been intensively used as a powerful radiogenic tracer to characterize old crust/sediment components in mantle- derived, terrestrial oceanic island basalts. The U-Th-Pb analyses are applied to sequential acid leaching fractions obtained from Tissint whole-rock powder in order to search for Pb isotopic source components in Tissint magma. Here we report preliminary results of the U-Th-Pb analyses of acid leachates and a residue, and propose the possibility that Tissint would have experienced minor assimilation of old martian crust.
Impact Histories of Vesta and Vestoids inferred from Howardites, Eucrites, and Diogenites
NASA Technical Reports Server (NTRS)
Scott, E. R. D.; Bogard, D. D.; Bottke, W. F.; Taylor, G. J.; Greenwood, R. C.; Franchi, I. A.; Keil, K.; Moskovitz, N. A.; Nesvorny, D.
2009-01-01
The parent body of the howardites, eucrites and diogenites (HEDs) is thought to be asteroid (4) Vesta [1]. However, several eucrites have now been recognized, like NWA 011 and Ibitira, with major element compositions and mineralogy like normal eucrites but with different oxygen isotope compositions and minor element concentrations suggesting they are not from the same body [2, 3]. The discoveries of abnormal eucrites and V-type asteroids that are probably not from Vesta [see 4] raise the question whether the HEDs with normal oxygen isotopes are coming from Vesta [3]. To address this issue and understand more about the evolution of Vesta in preparation for the arrival of the Dawn spacecraft, we integrate fresh insights from Ar-Ar dating and oxygen isotope analyses of HEDs, radiometric dating of differentiated meteorites, as well as dynamical and astronomical studies of Vesta, the Vesta asteroid family (i.e., the Vestoids), and other V-type asteroids.
NASA Technical Reports Server (NTRS)
Lundberg, Laura L.; Crozaz, Ghislaine; Mcsween, Harry Y., Jr.
1990-01-01
Analyses of mineral REE and selected minor and trace elements were carried out on individual grains of pyroxenes, whitlockite, maskelynite, and olivine of the Antarctic shergottite ALHA77005, and the results are used to interpret its parent magma and crystallization history. The results of mineral compositions and textural observations suggest that ALHA77005 is a cumulate with about half cumulus material (olivine + chromite) and half postcumulus phases. Most of the REEs in ALHA77005 reside in whitlockite whose modal concentration is about 1 percent. Mineral REE data support previous suggestions that plagioclase and whitlockite crystallized late, and that low-Ca pyroxene initiated crystallization before high-Ca pyroxene. The REE patterns for the intercumulus liquid, calculated from distribution coefficients for ALHA77005 pyroxene, plagioclase, and whitlockite, are in very good agreement and are similar to that of Shergotty.
Carlton, R.W.; Koeberl, C.; Baranoski, M.T.; SchuMacHer, G.A.
1998-01-01
The origin of the Serpent Mound structure in south-central Ohio has been disputed for many years. Clearly, more evidence was needed to resolve the confusion concerning the origin of the Serpent Mound feature either by endogenic processes or by hypervelocity impact. A petrographic study of 21 samples taken from a core 903 m long drilled in the central uplift of the structure provides evidence of shock metamorphism in the form of multiple sets of planar deformation features in quartz grains, as well as the presence of clasts of altered impact-melt rock. Crystallographic orientations of the planar deformation features show maxima at the shock-characteristic planes of {101??3} and {101??2} and additional maxima at {101??1}, {213??1}, and {516??1}. Geochemical analyses of impact breccias show minor enrichments in the abundances of the siderophile elements Cr, Co, Ni, and Ir, indicating the presence of a minor meteoritic component.
Minor elements, HREE and d18O distribution in UHP garnets from the Dora-Maira massif (western Alps)
NASA Astrophysics Data System (ADS)
Brunet, F.; Chazot, G.; Vielzeuf, D.; Chopin, C.
2003-04-01
The spatial distribution of minor elements, HREE and δ18O in garnet can be used as a probe of the availability and mobility of those elements and isotopes at the time of crystal growth, provided that the initial record was not significantly modified by intracrystalline diffusion and that growth took place under nearly constant pressure and temperature conditions. Garnets from three different Dora-Maira rock-types have been studied, (1) nearly pure pyrope (GT1) from the magnesian coesite-bearing quartzites, (2) almandine/pyrope dominant garnets (GT2) from jadeite-quartzite veins which crosscut the Mg-quartzite body, (3) almandine/grossular dominant garnets (GT3) from the country-rock gneiss, sampled in the vicinity of the quartzites. In GT1, minor elements are mainly Fe, Na and P. Na and P are incorporated according to a Na^+ + P5+ = Me2+ + Si4+ substitution with P_2O_5 contents up to 2000 to 2500 ppm. HREE concentrations obtained by LA-ICP-MS, vary by 2 orders of magnitude from core to rim. The δ18O ratio (Cameca 1270, Nancy), around 5 ppm (SMOW), is constant within error throughout the analysed crystals. In GT2, the situation is different since HREE concentrations appear remarkably constant within a given crystal and from one crystal to the other. In contrast with GT1, Na in GT2 is partly charge-balanced by yttrium incorporation. The δ18O ratio in GT2 of around 7 ppm is close to that encountered in GT3 (gneiss) between 7 and 8 ppm. In GT3, phosphorus content is close to detection limit (P_2O_5 below 300 ppm). HREE concentrations are highly variable from one crystal to the other and unfortunately, the size of garnet crystals does not allow profiling. Although δ18O ratio in garnet is imposed by the bulk-rock isotopic composition, HREE distribution is dominated by element availability through the fluid composition and/or absence/presence of accessory phases. The decrease in HREE and P concentration from GT1 cores to rims suggest that these elements are preferentially incorporated into garnet. Garnet growth leads to progressive depletion of these elements in the matrix. There is no significant influx of HREE during UHP garnet growth. The homogeneity of the δ18O ratio within garnet crystals is also an indication of UHP growth in a close metamorphic system. Jadeite-quartzite veins have geochemical characteristics close to that of the country-rock gneiss from which they could originate. They would then represent an evidence of Mg-quartzite and country gneiss interaction at UHP.
Geology and phosphate resources of the Hawley Creek area, Lemhi County, Idaho
Oberlindacher, Peter; Hovland, Robert David
1979-01-01
Phosphate resources occur within the Retort Phosphatic Shale Member of the Permian Phosphoria Formation in the Hawley Creek area, near Leadore, in east-central Idaho. About 12 square miles (31 km2 ) of the Retort Member and enclosing rocks were mapped at a scale of 1:12,000 to evaluate the leasable Federal mineral resources. The Retort has an average thickness of 73 feet (22.3 m) and 12.9 linear miles (20.8 linear km) of outcrop within the area mapped. Rock samples taken from a bulldozer trench were analyzed for phosphate content and for minor trace elements. Analyses show a cumulative thickness of 8.7 feet ( 2.7 m) of medium-grade phosphate rock ( 24 to 31 percent P2O5) and 33.4 feet (10.2 m) of low-grade phosphate rock (16 to 24 percent P2O5). Minor elements in the Retort include uranium, vanadium, fluorine, cadmium, chromium, nickel, molybdenum, silver, and rare earths. These minor elements are potential byproducts of any future phosphate production in the Hawley Creek area. In addition, analyses of six phosphate rock samples taken from a prospect trench show a cumulative thickness of 14.9 ft (4.5 m) at 17.6 percent P2O5. Indicated phosphate resources are calculated for phosphate beds under less than 600 feet (183.0 m) of overburden. Approximately 36.5 feet (11.1 m), representing 50 percent of the total Retort Member, were measured in trench CP-71. There are 80.42 million short tons (72.96 million metric tons) of medium-grade phosphate rock, and 308.76 million short tons ( 280.10 million metric tons) of low-grade phosphate rock in the Retort Member within the map area. Because the thickness and grade of the phosphate beds for each block are based on the recovered section from CP-71, the calculated phosphate resource estimates represent a minimum. Other mineral resources in the area are thorium (35 ppm) in a Precambrian (?) granite body located immediately west of the Hawley Creek area; oil and gas accumulations may occur beneath the Medicine Lodge thrust system in this part of the Beaverhead Mountains. Paleozoic, Mesozoic, and Cenozoic rocks are present in the Hawley Creek area. Fold axes and thrust faults have a dominant northwest trend. These thrusts and folds are probably associated with the northeast-oriented stress field that existed in Late Cretaceous time. Evidence of younger, high-angle normal and reverse faults in the area also exists.
Tourtelot, H.A.
1964-01-01
The composition of nonmarine shales of Cretaceous age that contain less than 1 per cent organic carbon is assumed to represent the inherited minor-element composition of clayey sediments delivered to the Cretaceous sea that occupied the western interior region of North America. Differences in minor-element content between these samples and samples of 1. (a) nonmarine carbonaceous shales (1 to 17 per cent organic carbon), 2. (b) nearshore marine shales (less than 1 per cent organic carbon), and 3. (c) offshore marine shales (as much as 8 per cent organic carbon), all of the same age, reveal certain aspects of the role played by clay minerals and organic materials in affecting the minor-element composition of the rocks. The organic carbon in the nonmarine rocks occurs in disseminated coaly plant remains. The organic carbon in the marine rocks occurs predominantly in humic material derived from terrestrial plants. The close similarity in composition between the organic isolates from the marine samples and low-rank coal suggests that the amount of marine organic material in these rocks is small. The minor-element content of the two kinds of nonmarine shales is the same despite the relatively large amount of organic carbon in the carbonaceous shales. The nearshore marine shales, however, contain larger median amounts of arsenic, boron, chromium, vanadium and zinc than do the nonmarine rocks; and the offshore marine shales contain even larger amounts of these elements. Cobalt, molybdenum, lead and zirconium show insignificant differences in median content between the nonmarine and marine rocks, although as much as 25 ppm molybdenum is present in some offshore marine samples. The gallium content is lower in the marine than in the nonmarine samples. Copper and selenium contents of the two kinds of nonmarine rocks and the nearshore marine samples are the same, but those of the offshore samples are larger. In general, arsenic, chromium, copper, molybdenum, selenium, vanadium and zinc are concentrated in those offshore marine samples having the largest amounts of organic carbon, but samples with equal amounts of vanadium, for instance, may differ by a factor of 3 in their amount of organic carbon. Arsenic and molybdenum occur in some samples chiefly in syngenetic pyrite but also are present in relatively large amounts in samples that contain little pyrite. The data on nonmarine carbonaceous shales indicate that organic matter of terrestrial origin in marine shales contributes little to the minor-element content of such rocks. It is possible that marine organic matter, even though seemingly small in amount in marine shales, contributes to the minor-element composition of the shales. In addition to any such contribution, however, the great effectiveness in sorption processes of humic materials in conjunction with clay minerals suggests that such processes must have played an important role as these materials moved from the relatively dilute solutions of the nonmarine environment to the relatively concentrated solution of sea water. The volumes of sea water sufficient to supply for sorption the amounts of most minor elements in the offshore marine samples are insignificant compared to the volumes of water with which the clay and organic matter were in contact during their transportation and sedimentation. Consequently, the chemical characteristics of the environment in which the clay minerals and organic matter accumulated and underwent diagenesis probably were the most important factors in controlling the degree to which sorption processes and the formation of syngenetic minerals affected the final composition of the rocks. ?? 1969.
ERIC Educational Resources Information Center
Sulfridge, Rocky M.
2012-01-01
This dissertation explores the website usage of adolescent sexual minorities, examining notions of information seeking and sexual identity development. Sexual information seeking is an important element within human information behavior and is uniquely problematic for young sexual minorities. Utilizing a contemporary gay teen website, this…
Asian American Middleman Minority Theory. The Constructional Framework of an American Myth. Draft.
ERIC Educational Resources Information Center
Wong, Eugene Franklin
This paper questions the applicability of middleman minority theory to Chinese and Japanese Americans. The constructional elements of the theory, in its American form, are analyzed in the context of Chinese and Japanese American economic, social, and political conditions. The ethnic group triad (elite-middleman minority-masses) is identified and…
NASA Technical Reports Server (NTRS)
Kent, J. J.; Brandon, A. D.; Lapen, T. J.; Peslier, A. H.; Irving, A. J.; Coleff, D. M.
2012-01-01
Northwest Africa (NWA) 5744 meteorite is a granulitic and troctolitic lunar breccia which may represent nearly pristine lunar crust (Fig. 1). NWA 5744 is unusually magnesian compared to other lunar breccias, with bulk [Mg/(Mg+Fe)] 0.79 [1, 2]. Inspection shows impactor content is likely to be very minor, with low Ni content and a lack of metal grains. Some terrestrial contamination is present, evidenced by calcite within cracks. NWA 5744 has notably low concentrations of incompatible trace elements (ITEs) [2]. The goal of this study is to attempt to classify this lunar granulite through analyses of in situ phases.
Local structures around the substituted elements in mixed layered oxides
Akama, Shota; Kobayashi, Wataru; Amaha, Kaoru; Niwa, Hideharu; Nitani, Hiroaki; Moritomo, Yutaka
2017-01-01
The chemical substitution of a transition metal (M) is an effective method to improve the functionality of a material, such as its electrochemical, magnetic, and dielectric properties. The substitution, however, causes local lattice distortion because the difference in the ionic radius (r) modifies the local interatomic distances. Here, we systematically investigated the local structures in the pure (x = 0.0) and mixed (x = 0.05 or 0.1) layered oxides, Na(M1−xM′x)O2 (M and M′ are the majority and minority transition metals, respectively), by means of extended X-ray absorption fine structure (EXAFS) analysis. We found that the local interatomic distance (dM-O) around the minority element approaches that around the majority element to reduces the local lattice distortion. We further found that the valence of the minority Mn changes so that its ionic radius approaches that of the majority M. PMID:28252008
Rare Earth Element Concentration of Wyoming Thermal Waters Update
DOE Office of Scientific and Technical Information (OSTI.GOV)
Quillinan, Scott; Nye, Charles; Neupane, Hari
Updated version of data generated from rare earth element investigation of produced waters. These data represent major, minor, trace, isotopes, and rare earth element concentrations in geologic formations and water associated with oil and gas production.
Garrison, Virginia; Lamothe, Paul; Morman, Suzette; Plumlee, Geoffrey S.; Gilkes, Robert; Prakongkep, Nattaporn
2010-01-01
The Sahara and Sahel lose billions of tons of eroded mineral soils annually to the Americas and Caribbean, Europe and Asia via atmospheric transport. African dust was collected from a dust source region (Mali, West Africa) and from downwind sites in the Caribbean [Trinidad-Tobago (TT) and U.S. Virgin Islands (VI)] and analysed for 32 trace-elements. Elemental composition of African dust samples was similar to that of average upper continental crust (UCC), with some enrichment or depletion of specific trace-elements. Pb enrichment was observed only in dust and dry deposition samples from the source region and was most likely from local use of leaded gasoline. Dust particles transported long-distances (VI and TT) exhibited increased enrichment of Mo and minor depletion of other elements relative to source region samples. This suggests that processes occurring during long-distance transport of dust produce enrichment/depletion of specific elements. Bioaccessibility of trace-metals in samples was tested in simulated human fluids (gastric and lung) and was found to be greater in downwind than source region samples, for some metals (e.g., As). The large surface to volume ratio of the dust particles (<2.5 µm) at downwind sites may be a factor.
Blackman, LM; Boevink, P; Cruz, SS; Palukaitis, P; Oparka, KJ
1998-01-01
The location of the 3a movement protein (MP) of cucumber mosaic virus (CMV) was studied by quantitative immunogold labeling of the wild-type 3a MP in leaves of Nicotiana clevelandii infected by CMV as well as by using a 3a-green fluorescent protein (GFP) fusion expressed from a potato virus X (PVX) vector. Whether expressed from CMV or PVX, the 3a MP targeted plasmodesmata and accumulated in the central cavity of the pore. Within minor veins, the most extensively labeled plasmodesmata were those connecting sieve elements and companion cells. In addition to targeting plasmodesmata, the 3a MP accumulated in the parietal layer of mature sieve elements. Confocal imaging of cells expressing the 3a-GFP fusion protein showed that the 3a MP assembled into elaborate fibrillar formations in the sieve element parietal layer. The ability of 3a-GFP, expressed from PVX rather than CMV, to enter sieve elements demonstrates that neither the CMV RNA nor the CMV coat protein is required for trafficking of the 3a MP into sieve elements. CMV virions were not detected in plasmodesmata from CMV-infected tissue, although large CMV aggregates were often found in the parietal layer of sieve elements and were usually surrounded by 3a MP. These data suggest that CMV traffics into minor vein sieve elements as a ribonucleoprotein complex that contains the viral RNA, coat protein, and 3a MP, with subsequent viral assembly occurring in the sieve element parietal layer. PMID:9548980
NASA Technical Reports Server (NTRS)
Lepore, K. H.; Mackie, J.; Dyar, M. D.; Fassett, C. I.
2017-01-01
Information on emission lines for major and minor elements is readily available from the National Institute of Standards and Technology (NIST) as part of the Atomic Spectra Database. However, tabulated emission lines are scarce for some minor elements and the wavelength ranges presented on the NIST database are limited to those included in existing studies. Previous work concerning minor element calibration curves measured using laser-induced break-down spectroscopy found evidence of Zn emission lines that were not documented on the NIST database. In this study, rock powders were doped with Rb, Ce, La, Sr, Y, Zr, Pb and Se in concentrations ranging from 10 percent to 10 parts per million. The difference between normalized spectra collected on samples containing 10 percent dopant and those containing only 10 parts per million were used to identify all emission lines that can be detected using LIBS (Laser-Induced Breakdown Spectroscopy) in a ChemCam-like configuration at the Mount Holyoke College LIBS facility. These emission spectra provide evidence of many previously undocumented emission lines for the elements measured here.
Cigars, youth, and the Internet link.
Malone, R E; Bero, L A
2000-01-01
OBJECTIVES: This study examined the accessibility and appeal to youth of cigar marketing sites on the Internet. METHODS: Sites marketing cigars (n = 141) were examined for age restrictions, prices, health warnings, and other elements. RESULTS: Although it is illegal for minors to purchase tobacco, only 36 sites (25.5%) prohibited purchases by minors. Sites offered low prices, and 32% accepted money orders, cashier's checks, or cash-on-delivery (COD) orders. Almost 30% of the sites included elements with potential youth appeal; only 3.5% displayed health warnings. CONCLUSIONS: The unregulated promotion of cigars on the Internet has the potential to attract youth, and there are few barriers to Internet tobacco purchases by minors. PMID:10800432
NASA Astrophysics Data System (ADS)
Cho, Lawrence; Kim, Myung Soo; Kim, Young Ha; De Cooman, Bruno C.
2014-09-01
The influence of the addition of minor alloying elements on the selective oxidation and the reactive wetting of CMnSi transformation-induced plasticity (TRIP) steels was studied by means of galvanizing simulator tests. Five TRIP steels containing small alloying additions of Cr, Ni, Ti, Cu, and Sn were investigated. After intercritical annealing (IA) at 1093 K (820 °C) in a N2 + 5 pct H2 gas atmosphere with a dew point of 213 K (-60 °C), two types of oxides were formed on the strip surface: Mn-rich xMnO·SiO2 ( x > 1.5) and Si-rich xMnO·SiO2 ( x < 0.3) oxides. The addition of the minor alloying elements changed the morphology of the Si-rich oxides from a continuous film to discrete islands and this improved the wettability by molten Zn. The improved wetting effect of the minor alloying elements was attributed to an increased area fraction of the surface where the oxides were thinner, enabling a direct unhindered reaction between Fe and the Al in the liquid Zn and the formation of the inhibition layer during the hot dip galvanizing. The addition of a small amount of Sn is shown to significantly decrease the density of Zn-coating defects on CMnSi TRIP steels.
Couple-level Minority Stress: An Examination of Same-sex Couples' Unique Experiences.
Frost, David M; LeBlanc, Allen J; de Vries, Brian; Alston-Stepnitz, Eli; Stephenson, Rob; Woodyatt, Cory
2017-12-01
Social stress resulting from stigma, prejudice, and discrimination-"minority stress"-negatively impacts sexual minority individuals' health and relational well-being. The present study examined how being in a same-sex couple can result in exposure to unique minority stressors not accounted for at the individual level. Relationship timeline interviews were conducted with 120 same-sex couples equally distributed across two study sites (Atlanta and San Francisco), gender (male and female), and relationship duration (at least six months but less than three years, at least three years but less than seven years, and seven or more years). Directed content analyses identified 17 unique couple-level minority stressors experienced within nine distinct social contexts. Analyses also revealed experiences of dyadic minority stress processes (stress discrepancies and stress contagion). These findings can be useful in future efforts to better understand and address the cumulative impact of minority stress on relational well-being and individual health.
NASA Astrophysics Data System (ADS)
Alizadeh Behjani, Mohammadreza; Hassanpour, Ali; Ghadiri, Mojtaba; Bayly, Andrew
2017-06-01
Segregation of granules is an undesired phenomenon in which particles in a mixture separate from each other based on the differences in their physical and chemical properties. It is, therefore, crucial to control the homogeneity of the system by applying appropriate techniques. This requires a fundamental understanding of the underlying mechanisms. In this study, the effect of particle shape and cohesion has been analysed. As a model system prone to segregation, a ternary mixture of particles representing the common ingredients of home washing powders, namely, spray dried detergent powders, tetraacetylethylenediamine, and enzyme placebo (as the minor ingredient) during heap formation is modelled numerically by the Discrete Element Method (DEM) with an aim to investigate the effect of cohesion/adhesion of the minor components on segregation quality. Non-spherical particle shapes are created in DEM using the clumped-sphere method based on their X-ray tomograms. Experimentally, inter particle adhesion is generated by coating the minor ingredient (enzyme placebo) with Polyethylene Glycol 400 (PEG 400). The JKR theory is used to model the cohesion/adhesion of coated enzyme placebo particles in the simulation. Tests are carried out experimentally and simulated numerically by mixing the placebo particles (uncoated and coated) with the other ingredients and pouring them in a test box. The simulation and experimental results are compared qualitatively and quantitatively. It is found that coating the minor ingredient in the mixture reduces segregation significantly while the change in flowability of the system is negligible.
Viets, J.G.; Leach, D.L.; Lichte, F.E.; Hopkins, R.T.; Gent, C.A.; Powell, J.W.
1996-01-01
Paragenetic and minor- and trace-element studies were conducted on samples of epigenetic ore and gangue minerals collected from mines and drill core in the Silesian-Cracow (S-C) district of southern Poland. Four discrete mineral suites representing four mineralizing stages can be identified throughout the district. The earliest epigenetic minerals deposited during stage 1 consist of a late dolomite cement together with minor pyrite and marcasite. Stage 2 was the first ore-forming stage and included repetitive deposition of sphalerite and galena in a variety of morphologies. Stage 3 abruptly followed the first ore stage and deposited marcasite and pyrite with variable amounts of late sphalerite and galena. In the samples studied, minerals deposited during stage 3 are predominately marcasite-pyrite with minor sphalerite and galena in the Pomorzany and Olkusz mines, whereas, at the Trzebionka mine, stage 3 mineralization deposited mostly galena and sphalerite with little marcasite or pyrite. Stage 4 minerals include contains barite, followed by calcite, with very minor pyrite and a rare, late granular sphalerite. Compared to other major Mississippi Valley-type (MVT) districts of the world, the Silesian-Cracow district contains sphalerite with the second largest range in Ag concentrations and the largest range in Fe and Cd concentrations of any district. Unlike in other districts, very wide ranges in minor- and trace-element concentrations are also observed in paragenetically equivalent samples collected throughout the district. This wide range indicates that the minor- and trace-element content of the ore-forming environment was highly variable, both spatially and temporally, and suggests that the hydrologic system that the ore fluids traversed from their basinal source was very complex. Throughout the district, a significant increase in Tl, Ge, and As concentrations is accompanied by a lightening of sulfur isotopes between stage 2 and stage 3 minerals. This change appears to record a major district-scale hydrologic event that probably reflects the introduction of fluids with significantly different geochemistry than that of earlier ore-forming fluids.
Leventhal, Joel S.
1979-01-01
Core samples from Devonian shales from five localities in the Appalachian Basin have been analyzed for major, minor, and trace constituents. The contents of major elements are rather similar; however, the minor constituents, organic C, S, PO4, and CO3, show variations by a factor of 10. Trace elements Mo, Ni, Cu, V, Co, U, Zn, Hg, As, and Mn show variations that can be related graphically and statistically to the minor constituents. Down-hole plots show the relationships most clearly. Mn is associated with CO3 content, the other trace elements are strongly Controlled by organic C. Amounts of organic C are generally in the range of 3-6 percent, and S is in the range of 2-5 percent. Trace-element amounts show the following general ranges (ppm, parts per million)- Co, 20-40; Cu,40-70; U, 10-40; As, 20-40, V, 150-300; Ni, 80-150; high values are as much as twice these values. The organic C was probably the concentrating agent, whereas the organic C and sulfide S created an environment for preservation or immobilization of trace elements. Closely spaced samples showing an abrupt transition in color from black to gray and gray to black shale show similar effects of trace-element changes, that is, black shale contains enhanced amounts of organic C and trace elements. Ratios of trace elements to organic C or sulfide S were relatively constant even though deposition rates varied from 10 to 300 meters in 5 million years.
ERIC Educational Resources Information Center
Lawrence, Michael A.
1985-01-01
"Narrowcasting" is information and entertainment aimed at specific population segments, including previously ignored minorities. Cable, satellite, videodisc, low-power television, and video cassette recorders may all help keep minorities from being "information poor." These elements, however, are expensive, and study is needed to understand how…
Major, minor, trace and rare earth elements in sediments of the Bijagós archipelago, Guinea-Bissau.
Carvalho, Lina; Figueira, Paula; Monteiro, Rui; Reis, Ana Teresa; Almeida, Joana; Catry, Teresa; Lourenço, Pedro Miguel; Catry, Paulo; Barbosa, Castro; Catry, Inês; Pereira, Eduarda; Granadeiro, José Pedro; Vale, Carlos
2018-04-01
Sixty sediment samples from four sites in the Bijagós archipelago were characterized for fine fraction, loss on ignition, major, minor and trace elemental composition (Al, Fe, Ca, Mg, Ti, P, Zr, Mn, Cr, Sr, Ba, B, V, Li, Zn, Ni, Pb, As, Co, U, Cu, Cs and Cd), and the elements of the La-Lu series. Element concentrations were largely explained by the Al content and the proportion of fine fraction content, with the exception of Ca and Sr. Sediments showed enhanced Ti, U, Cr, As and Cd concentrations with respect to estimated upper crust values, most likely mirroring a regional signature. Rare earth elements were in deficit relatively to the North American Shale Composite (NASC), mainly in coarser material. No pronounced Ce-anomaly was observed, while Eu-anomalies were positive in most analyzed sediments. Copyright © 2017 Elsevier Ltd. All rights reserved.
Signatures in Martian Volatiles and the Magma Sources of NC Meteorites
NASA Technical Reports Server (NTRS)
Marti, K.; Mathew, K. J.
2004-01-01
We report nitrogen and xenon isotopic signatures in Yamato nakhlites and use the data to assess properties of the magma source of NC meteorites in planet Mars. The Chassigny meteorite was investigated by Floran et al, who classified it as a cumulate dunite with hydrous amphibole-bearing melt inclusions with no preferred orientation of the olivines. Their inferred composition of the parent magma, which was based on electron microprobe analyses, has been questioned. The trace and minor elements in minerals were analyzed in nakhlites and in Chassigny and the authors conclude that nakhlites may represent samples from different horizons of the same lithologic unit, but that Chassigny was not co-magmatic with the nakhlites.
Correlation of Mechanical Properties with Diameter and Cooling Rate of 1080 Wire-Rod
NASA Astrophysics Data System (ADS)
Kohli, A.; Poirier, D. R.
2017-12-01
More than 540 heats of 1080 wire-rod were statistically analyzed by regression analyses to see whether tensile strength and percent reduction in area (%RA) relate to wire-rod diameter and composition. As diameter increases from 5.6 to 12.7 mm, the trend in %RA shows a decrease with negligible effect on the trend of the tensile strength. It was found that the estimated cooling rate at 700 °C during controlled cooling is responsible for the "diameter effect." The effect of composition on %RA is minor when contrasted to the "diameter effect." In particular, the effect of the concentrations of the residual elements on %RA within the compositional range studied is negligible.
Moyle, Phillip R.; Causey, J. Douglas
2001-01-01
This report provides chemical analyses for 31 samples collected from various phosphate mine sites in southeastern Idaho (25), northern Utah (2), and western Wyoming (4). The sampling effort was undertaken as a reconnaissance and does not constitute a characterization of mine wastes. Twenty-five samples were collected from waste rock dumps, 2 from stockpiles, and 1 each from slag, tailings, mill shale, and an outcrop. All samples were analyzed for a suite of major, minor, and trace elements. Although the analytical data set for the 31 samples is too small for detailed statistical analysis, a summary of general observations is made.
NASA Technical Reports Server (NTRS)
Flynn, G. J.; Sutton, S. R.
1992-01-01
Major-element abundances in 11 C, C?, and TCA cosmic dust particles have been measured using SEM and TEM energy dispersive X-ray (EDX) systems. The Fe/Ni ratio, when coupled with major element abundances, appears to be a useful discriminator of cosmic particles. Three particles classified as C?, but having Fe/Ni peak height ratios similar to those measured on the powdered Allende meteorite sample in their HSC EDX spectra, exhibit chondritic minor-/trace-element abundance patterns, suggesting they are extraterrestrial. The one particle classified as C-type, but without detectable Ni in its JSC EDX spectrum, exhibits an apparently nonchondritic minor-/trace-element abundance pattern. A class of particles that are chondritic except for large depletions in the volatile elements Zn and S has been identified. It is likely that these particles condensed with a C1 abundance pattern and that Zn and S were removed by some subsequent process.
Electron-probe microanalysis of light elements in coal and other kerogen
Bustin, R.M.; Mastalerz, Maria; Raudsepp, M.
1996-01-01
Recent advances in electron microprobe technology including development of layered synthetic microstructures, more stable electronics and better matrix-correction programs facilitated routine microanalysis of the light elements in coal. Utilizing an appropriately equipped electron microprobe with suitable standards, it is now possible to analyze directly the light elements (C, O and N, if abundant) in coal macerals and other kerogen. The analytical results are both accurate compared to ASTM methods and highly precise, and provide an opportunity to access the variation in coal chemistry at the micrometre scale. Our experiments show that analyses using a 10 kV accelerating voltage and 10 nA beam current yield the most reliable data and result in minimum sample damage and contamination. High sample counts were obtained for C, O and N using a bi-elemental nickel-carbon pseudo-crystal (2d = 9.5 nm) as an analyzing crystal. Vitrinite isolated from anthracite rank coal proves the best carbon standard and is more desirable than graphite which has higher porosity, whereas lower rank vitrinite is too heterogeneous to use routinely as a standard. Other standards utilized were magnesite for oxygen and BN for nitrogen. No significant carbon, oxygen or nitrogen X-ray peak shifts or peak-shape changes occur between standards and the kerogen analyzed. Counting rates for carbon and oxygen were found to be constant over a range of beam sizes and currents for counting times up to 160 s. Probe-determined carbon and oxygen contents agree closely with those reported from ASTM analyses. Nitrogen analyses compare poorly to ASTM values which probably is in response to overlap between the nitrogen Ka peak with the carbon K-adsorption edge and the overall low nitrogen content of most of our samples. Our results show that the electron microprobe technique provides accurate compositional data for both minor and major elements in coal without the necessity and inherent problems associated with mechanically isolating macerals. Studies to date have demonstrated the level of compositional variability within and between macerals in suites of Canadian coals.
NASA Astrophysics Data System (ADS)
Raia, N. H.; Cooperdock, E. H. G.; Barnes, J.; Stockli, D. F.; Schwarzenbach, E. M.
2016-12-01
Serpentinized ultramafic rocks are commonly found in exhumed HP/LT subduction complexes, but their tectonic origins (i.e., setting of serpentinization) are difficult to decipher due to extensive alteration. Growing literature and geochemical datasets demonstrate that immobile elements (REE, HFSE) in serpentinites can retain magmatic signatures indicative of the tectonic setting of parent peridotite, while fluid-mobile elements and stable isotopic signatures shed light on the fluids causing serpentinization. This study combines whole-rock trace and major element geochemistry, stable isotope (δD and δO) analyses with petrographic observation to determine the tectonic origin of ultramafic rocks in the HP/LT Aegean subduction complex. The best-preserved HP rocks of the Cycladic Blueschist Unit (CBU) are found on Syros, Greece, where serpentinized ultramafic rocks within the CBU are closely associated with metamorphosed remnants of subducted oceanic crust. All samples are completely serpentinized, lacking relict pyroxene or spinel grains, with typical assemblages consisting of serpentine, talc, chlorite, magnetite, and minor carbonate. The serpentinizing fluid was characterized using stable isotopes. δD and δO values of bulk-rock serpentinite powders and chips, respectively, suggest seafloor serpentinites hydrated by seawater at low T, typical of alteration at mid-ocean ridges and hyper-extended margins (δD = -64 to -33‰ and δO = 5.2 to 9.0‰). To fingerprint a tectonic origin, whole rock serpentinite REE patterns are compared to a global database of whole rock serpentinite analyses from fore-arc mantle wedge, mid-ocean ridge, and hyper-extended margin tectonic settings. Whole rock major element, trace element, and REE analyses are consistent with limited melt extraction, flat REE patterns (LaN/SmN = 0.2-2.6, SmN/YbN = 0.3-3.5; N= C1 normalized), and do not show pronounced Eu anomalies. These data are consistent with abyssal peridotites derived from hyper-extended margin settings, although some overlap with mid-ocean ridge serpentinites makes it difficult to rule out. In any case, the geochemical signatures retained in these serpentinites indicate they are unlikely sourced from the mantle wedge, as has been historically speculated.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Clegg, Samuel M; Barefield, James E; Wiens, Roger C
2008-01-01
The ChemCam instrument on the Mars Science Laboratory (MSL) will include a laser-induced breakdown spectrometer (LIBS) to quantify major and minor elemental compositions. The traditional analytical chemistry approach to calibration curves for these data regresses a single diagnostic peak area against concentration for each element. This approach contrasts with a new multivariate method in which elemental concentrations are predicted by step-wise multiple regression analysis based on areas of a specific set of diagnostic peaks for each element. The method is tested on LIBS data from igneous and metamorphosed rocks. Between 4 and 13 partial regression coefficients are needed to describemore » each elemental abundance accurately (i.e., with a regression line of R{sup 2} > 0.9995 for the relationship between predicted and measured elemental concentration) for all major and minor elements studied. Validation plots suggest that the method is limited at present by the small data set, and will work best for prediction of concentration when a wide variety of compositions and rock types has been analyzed.« less
Wildman, R.A.; Domagalski, Joseph L.; Hering, J.G.
2009-01-01
The relative influences of hydrologic processes and biogeochemistry on the transport and retention of minor solutes were compared in the riverbed of the lower Merced River (California, USA). The subsurface of this reach receives ground water discharge and surface water infiltration due to an altered hydraulic setting resulting from agricultural irrigation. Filtered ground water samples were collected from 30 drive point locations in March, June, and October 2004. Hydrologic processes, described previously, were verified by observations of bromine concentrations; manganese was used to indicate redox conditions. The separate responses of the minor solutes strontium, barium, uranium, and phosphorus to these influences were examined. Correlation and principal component analyses indicate that hydrologic processes dominate the distribution of trace elements in the ground water. Redox conditions appear to be independent of hydrologic processes and account for most of the remaining data variability. With some variability, major processes are consistent in two sampling transects separated by 100 m. Copyright ?? 2009 by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America. All rights reserved.
NMR structure of the 101-nucleotide core encapsidation signal of the Moloney murine leukemia virus.
D'Souza, Victoria; Dey, Anwesha; Habib, Dina; Summers, Michael F
2004-03-19
The full length, positive-strand genome of the Moloney Murine Leukemia Virus contains a "core encapsidation signal" that is essential for efficient genome packaging during virus assembly. We have determined the structure of a 101-nucleotide RNA that contains this signal (called mPsi) using a novel isotope-edited NMR approach. The method is robust and should be generally applicable to larger RNAs. mPsi folds into three stem loops, two of which (SL-C and SL-D) co-stack to form an extended helix. The third stem loop (SL-B) is connected to SL-C by a flexible, four-nucleotide linker. The structure contains five mismatched base-pairs, an unusual C.CG base-triple platform, and a novel "A-minor K-turn," in which unpaired adenosine bases A340 and A341 of a GGAA bulge pack in the minor groove of a proximal stem, and a bulged distal uridine (U319) forms a hydrogen bond with the phosphodiester of A341. Phylogenetic analyses indicate that these essential structural elements are conserved among the murine C-type retroviruses.
NASA Astrophysics Data System (ADS)
Aburada, Tomohiro
2011-12-01
The effects and mechanistic roles of a minor alloying element, Ni, on the localized corrosion behavior were explored by studying (Al75Cu 17Mg8)97Ni3 and Al70Cu 18Mg12 amorphous alloys. To explore the minor alloying element limited to the outer surface layers, the corrosion behavior of Al70Cu 18Mg12 amorphous alloy in solutions with and without Ni 2+ was also studied. Both Ni alloying and Ni2+ in solution improved the localized corrosion resistance of the alloys by ennobling the pitting and repassivation potentials. Pit growth by the selective dissolution of Al and Mg was also suppressed by Ni alloying. Remaining Cu and Ni reorganized into a Cu-rich polycrystalline nanoporous structure with continuous ligaments in pits. The minor Ni alloying and Ni2+ in solution suppressed the coarsening of the ligaments in the dealloyed nanoporous structure. The presence of relatively immobile Ni atoms at the surface suppressed the surface diffusion of Cu, which reduced the coarsening of the nanoporous structure, resulting in the formation of 10 to 30 nm wide Cu ligaments. Two mechanistic roles of minor alloying elements in the improvement of the pitting corrosion resistance of the solid solution alloys are elucidated. The first role is the suppression of active dissolution by altering the atomic structure. Ni in solid solution formed stronger bonds with Al, and reduces the probability of weaker Al-Al bonds. The second role is to hinder dissolution by producing a greater negative shift of the true interfacial potential at the dissolution front under the dealloyed layer due to the greater Ohmic resistance through the finer porous structure. These effects contributed to the elevation of pitting potentials by ennobling the applied potential required to produce enough dissolution for the stabilization of pits. Scientifically, this thesis advances the state of understanding of alloy dissolution, particularly the role of minor alloying elements on preferential oxidation at the atomic, nanometer, and micrometer scales. Technological implementations of the findings of the research are also discussed, including a new route to synthesize nanoporous materials with tunable porosity and new corrosion mitigation strategies for commercial Al-based alloys containing the detrimental Al2CuMg phase.
Tannins and terpenoids as major precursors of Suwannee River fulvic acid
Leenheer, Jerry A.; Rostad, Colleen E.
2004-01-01
Suwannee River fulvic acid (SRFA) was fractionated into 7 fractions by normal-phase chromatography on silica gel followed by reverse-phase fractionation on XAD-8 resin that produced 18 subfractions. Selected major subfractions were characterized by 13C-nuclear magnetic resonance (NMR), infrared spectrometry, and elemental analyses. 13C-NMR spectra of the subfractions were more indicative of precursor structures than unfractionated SRFA, and gave spectral profiles that indicated SRFA mass was about equally split between tannin precursors and terpenoid precursors. Lignin precursors were minor components. Synthesis of 13C-NMR data with elemental data for subfractions derived from both tannin and terpenoid precursors revealed high ring contents and low numbers of carbon per rings which is indicative of fused ring structures that are extensively substituted with carboxyl and methyl groups. These results ruled out extended chain structures for SRFA. This information is useful for determining sources and properties of fulvic acid in drinking water supplies as tannins are more reactive with chlorine to produce undesirable disinfection by-products than are terpenoids.
NASA Technical Reports Server (NTRS)
Smith, J. V.; Hansen, E. C.; Steele, I. M.
1980-01-01
Lunar olivines from anorthosites, granulitic impactites, and rocks in the Mg-rich plutonic trend were subjected to electron probe measurements for Al, P, Ca, Ti, Cr and Mn, which show that the FeO/MnO ratio for lunar olivines lies between 80 and 110 with little difference among the rock types. The low values of Ca in lunar olivines indicate slow cooling to subsolidus temperatures, with blocking temperatures of about 750 C for 67667 and 1000 C for 60255,73-alpha determined by the Finnerty and Boyd (1978) experiments. An important paradox is noted in the low Ti content of Fe-rich olivines from anorthosites, although both Ti and Fe tend to become enriched in liquid during fractional distillation. Except for Ca and Mn, olivine from anorthosites has lower minor element values than other rock types. Formation from a chemically distinct system is therefore implied.
Elemental fractionation and magnetic properties of melt-based Y1Ba2Cu3Oz containing excess Tb or Pt
NASA Technical Reports Server (NTRS)
Hojaji, Hamid; Barkatt, Aaron; Hu, Shouxiang; Michael, Karen A.; Thorpe, Arthur N.; Talmy, Inna G.; Haught, Debbie A.; Alterescu, Sidney
1990-01-01
Scanning electron microscopy of certain partially melted Y-Ba-Cu-O materials containing minority metal oxide species (Y:Tb:Ba:Cu = 1:0.1:2:3 or Y:Ba:Cu with Pt impurities), accompanied by both EDX and EMP analysis, indicates that the minority species (Tb or Pt) is quantitatively concentrated in a relatively small number of 123-type grains. High magnetic susceptibility and magnetization observed for these materials indicate that such elemental distribution is not detrimental to superconducting behavior.
Late Holocene sedimentation in coastal areas of the northwestern Ross Sea (Antarctica)
NASA Astrophysics Data System (ADS)
Colizza, Ester; Finocchiaro, Furio; Kuhn, Gerhard; Langone, Leonardo; Melis, Romana; Mezgec, Karin; Severi, Mirko; Traversi, Rita; Udisti, Roberto; Stenni, Barbara; Braida, Martina
2013-04-01
Sediment cores and box cores collected in two coastal areas of the northwestern Ross Sea (Antarctica) highlight the possibility of studying the Late Holocene period in detail. In this work we propose a study on two box cores and two gravity cores collected in the Cape Hallett and Wood Bay areas during the 2005 PNRA oceanographic cruise. The two sites are feed by Eastern Antarctic Ice Shelf (EAIS) and previous studies have highlighted a complex postglacial sedimentary sequence, also influenced by local morphology. This study is performed within the framework of the PNRA-ESF PolarCLIMATE HOLOCLIP (Holocene climate variability at high-southern latitudes: an integrated perspective) Project. The data set includes: magnetic susceptibility, X-ray analyses, 210Pb, 14C dating, diatoms and foraminifera assemblages, organic carbon, and grain-size analyses. Furthermore XRF core scanner analyses, colour analysis from digital images, and major, minor and trace element concentration analyses (ICP-AES) are performed. Data show that the box core and upper core sediments represent a very recent sedimentation in which it is possible to observe the parameter variability probably linked to climate variability/changes: these variation will be compared with isotopic record form ice cores collected form the same Antarctic sector.
Gebhardt, J S; Nierzwicki-Bauer, S A
1991-01-01
Symbiotically associated cyanobacteria from Azolla mexicana and Azolla pinnata were isolated and cultured in a free-living state. Morphological analyses revealed differences between the free-living isolates and their symbiotic counterparts, as did restriction fragment length polymorphism (RFLP) analyses with both single-copy glnA and rbcS gene probes and a multicopy psbA gene probe. RFLP analyses with Anabaena sp. strain PCC 7120 nifD excision element probes, including an xisA gene probe, detected homologous sequences in DNA extracted from the free-living isolates. Sequences homologous to these probes were not detected in DNA from the symbiotically associated cyanobacteria. These analyses indicated that the isolates were not identical to the major cyanobacterial symbiont species residing in leaf cavities of Azolla spp. Nevertheless, striking similarities between several free-living isolates were observed. In every instance, the isolate from A. pinnata displayed banding patterns virtually identical to those of free-living cultures previously isolated from Azolla caroliniana and Azolla filiculoides. These results suggest the ubiquitous presence of a culturable minor cyanobacterial symbiont in at least three species of Azolla. Images PMID:1685078
Building the Minority Faculty Development Pipeline.
ERIC Educational Resources Information Center
Gates, Paul E.; Ganey, James H.; Brown, Marc D.
2003-01-01
Describes efforts toward minority faculty development in dentistry, including those of Harlem Hospital-Columbia University School of Dentistry and Oral Surgery, the National Dental Association Foundation, and Bronx Lebanon Hospital Center. Explains that critical elements in the success of these programs are environment, selection criteria,…
Lima, A.; Belkin, H.E.; Torok, K.
1999-01-01
Microthermometric investigations of silicate-melt inclusions and electron microprobe analyses were conducted on experimentally homogenized silicate-melt inclusions and on the host clinopyroxenes from 4 scoria samples of different layers from the Mt. Somma-Vesuvius medieval eruption (Formazione di Terzigno, 893 A.D.). The temperature of homogenization, considered the minimum trapping temperature, ranges from 1190 to 1260??5 ??C for all clinopyroxene-hosted silicate melt inclusions. The major and minor-element compositional trends shown by Terzigno scoria and matrix glass chemical analysis are largely compatible with fractional crystallization of clinopyroxene and Fe-Ti oxides. Sulfur contents of the homogenized silicate-melt inclusions in clinopyroxene phenocrysts compared with that in the host scoria show that S has been significantly degassed in the erupted products; whereas, Cl has about the same abundance in the inclusions and in host scoria. Fluorine is low (infrequently up to 800 ppm) in the silicate-melt inclusions compared to 2400 ppm in the bulk scoria. Electron microprobe analyses of silicate-melt inclusions show that they have primitive magma compositions (Mg# = 75-91). The composition of the host clinopyroxene phenocrysts varies from typical plinian-related (Mg#???85) to non-plinian related (Mg#???85). The mixed source of the host clinopyroxenes and primitive nature of the silicate-melt inclusions implies that these phenocrysts, in part, may be residual and/or have a polygenetic origin. The similar variation trends of major and minor-elements between homogenized silicate-melt inclusions from the Terzigno scoria, and silicate-melt inclusions in olivine and diopside phenocrysts from plinian eruptions (Marianelli et al., 1995) suggest that the trapped inclusions represent melts similar to those that supplied the plinian and sub-plinian magma chambers. These geochemical characteristics suggest that the Vesuvius magmatic system retained a vestige of the most recent plinian event.
NASA Astrophysics Data System (ADS)
Fabre, C.; Maurice, S.; Cousin, A.; Wiens, R. C.; Forni, O.; Sautter, V.; Guillaume, D.
2011-03-01
Accurate characterization of the Chemistry Camera (ChemCam) laser-induced breakdown spectroscopy (LIBS) on-board composition targets is of prime importance for the ChemCam instrument. The Mars Science Laboratory (MSL) science and operations teams expect ChemCam to provide the first compositional results at remote distances (1.5-7 m) during the in situ analyses of the Martian surface starting in 2012. Thus, establishing LIBS reference spectra from appropriate calibration standards must be undertaken diligently. Considering the global mineralogy of the Martian surface, and the possible landing sites, three specific compositions of igneous targets have been determined. Picritic, noritic, and shergottic glasses have been produced, along with a Macusanite natural glass. A sample of each target will fly on the MSL Curiosity rover deck, 1.56 m from the ChemCam instrument, and duplicates are available on the ground. Duplicates are considered to be identical, as the relative standard deviation (RSD) of the composition dispersion is around 8%. Electronic microprobe and laser ablation inductively coupled plasma mass spectrometry (LA ICP-MS) analyses give evidence that the chemical composition of the four silicate targets is very homogeneous at microscopic scales larger than the instrument spot size, with RSD < 5% for concentration variations > 0.1 wt.% using electronic microprobe, and < 10% for concentration variations > 0.01 wt.% using LA ICP-MS. The LIBS campaign on the igneous targets performed under flight-like Mars conditions establishes reference spectra for the entire mission. The LIBS spectra between 240 and 900 nm are extremely rich, hundreds of lines with high signal-to-noise, and a dynamical range sufficient to identify unambiguously major, minor and trace elements. For instance, a first LIBS calibration curve has been established for strontium from [Sr] = 284 ppm to [Sr] = 1480 ppm, showing the potential for the future calibrations for other major or minor elements.
Rare Earth Element Geochemistry for Produced Waters, WY
Quillinan, Scott; Nye, Charles; McLing, Travis; Neupane, Hari
2016-06-30
These data represent major, minor, trace, isotopes, and rare earth element concentrations in geologic formations and water associated with oil and gas production. *Note - Link below contains updated version of spreadsheet (6/14/2017)
Venkatasalu, Munikumar Ramasamy
2017-09-02
To investigate older British South Asians' views on dying at acute hospitals. Older people, including those from ethnic minorities prefer 'home as a haven' for their last days of life; however, they are more likely to die in hospital. Constructive grounded theory was used as a methodological approach that informed data collection to data analysis. Open meetings with 11 local South Asian community organisations enabled the researchers to recruit a total of 55 older South Asians in this study. Data were collected using gender-based focus groups (n=5) and in-depth, semi-structured interviews (n=29). Transcripts were analysed using Nvivo 9. Three key themes were identified: 'mistrust', 'let him not be alone' and 'family as a protective shield'. The theme 'mistrust' is explored through examination of beliefs, attitudes and expectations about 'hospital' as a place in the care of the dying. The theme of 'let him not be alone' draws the family's preferences and concerns in relation to leaving their older dying relative alone in the hospital. The final theme of 'family as a protective shield' describes the element of family care as a protective shield for their older one to have peaceful end-of-life care moments in the hospital. Allowing older relatives to die in hospital seems to evoke feelings of missed filial responsibilities and guilt among family carers among older ethnic minorities. The presence of cultural paranoia and mistrust often led minorities to experience sub-standard end-of-life care in acute hospitals.
Insecure Identities: Unaccompanied Minors as Refugees in Hamburg
ERIC Educational Resources Information Center
Schroeder, Joachim
2012-01-01
This paper analyses the financial circumstances and social income of nearly one hundred unaccompanied minors who have come to Hamburg as refugees from various regions of Africa. It is based on extensive qualitative surveys, analysing their objective conditions of life and in particular their legal situation. A wide range of interview material and…
NASA Astrophysics Data System (ADS)
Mitchell, Andrew C.; Brown, Giles H.
2007-01-01
SummaryWe present diurnal (i) 0.45 and 0.1 μm pore-size filtered and (ii) operationally defined labile particulate-associated major, minor and trace element concentrations and fluxes in glacial outflow waters draining Haut Glacier d'Arolla, Switzerland. We use speciation modelling (PHREEQCi) and water-suspended sediment interaction experiments are utilised under conditions analogous to the subglacial channellised hydrological system, in order to assess controls on, and the most suitable sampling methods to investigate short-term variations in the mode of major, minor and trace element species export from a glacierised headwater catchment. 0.45 μm pore-size filtered major ions, Sr and U are exported in glacial outflow waters predominately as mobile monovalent or divalent ions or as carbonate complexes, and are controlled by hydrological variations over diurnal cycles, exhibiting an inverse concentration with increasing meltwater discharge. Conversely, 0.45 μm pore-size filtered concentrations of most minor and trace elements ( e.g. Fe, Mn, Co, Ba and Pb) exhibit variations that are not strongly inter-correlated with meltwater discharge or suspended sediment concentrations (SSC) over diurnal periods. The use of 0.45 and 0.1 μm pore-size filter membranes indicates that significant colloidal material is not passing through the 0.45 μm pore-size filters, and these unsystematic variations are not a result of colloid measurement. Speciation modelling applied to meltwaters and observations during water-rock interaction experiments suggest that these unsystematic temporal variations reflect physicochemical controls. This includes sorption, and the oversaturation and precipitation of Fe and Al (oxi)hydroxides, and the co-precipitation of other species. Diurnal pH variations appear important in controlling such short-term physicochemical controls, which limits such species use for hydrological investigations. The percentage of total elemental fluxes exported as the labile particulate-associated flux (%PAF) for each minor and trace element changes dramatically between and during the diurnal cycles, reflecting species-specific sensitivity to hydrological and physicochemical controls. Hydrological interpretations of hydrochemical data must be made carefully when using chemical determinations by ICP-MS, since we demonstrate that measurements will comprise of any material that passes through the filter. This can lead to higher concentration measurements than if determined by ion chromatography, which measures truly ionic dissolved species.
Minor element distribution in iron disulfides in coal: a geochemical review
Kolker, Allan
2012-01-01
Electron beam microanalysis of coal samples in U.S. Geological Survey (USGS) labs confirms that As is the most abundant minor constituent in Fe disulfides in coal and that Se, Ni, and other minor constituents are present less commonly and at lower concentrations than those for As. In nearly all cases, Hg occurs in Fe disulfides in coal at concentrations below detection by electron beam instruments. Its presence is shown by laser ablation ICP-MS, by selective leaching studies of bulk coal, and by correlation with Fe disulfide proxies such as total Fe and pyritic sulfur. Multiple generations of Fe disulfides are present in coal. These commonly show grain-to-grain and within-grain minor- or trace element compositional variation that is a function of the early diagenetic, coalification, and post-coalification history of the coal. Framboidal pyrite is almost always the earliest Fe disulfide generation, as shown by overgrowths of later Fe disulfides which may include pyrite or marcasite. Cleat- (or vein) pyrite (or marcasite) is typically the latest Fe disulfide generation, as shown by cross-cutting relations. Cleat pyrite forms by fluid migration within a coal basin and consequently may be enriched in elements such as As by deposition from compaction-driven fluids, metal enriched basinal brines or hydrothermal fluids. In some cases, framboidal pyrite shows preferential Ni enrichment with respect to co-occurring pyrite forms. This is consistent with bacterial complexing of metals in anoxic sediments and derivation of framboidal pyrite from greigite (Fe3S4), an Fe monosulfide precursor to framboidal pyrite having the thio-spinel structure which accommodates transition metals. Elements such as As, Se, and Sb substitute for S in the pyrite structure whereas metals, including transition metals, Hg and Pb, are thought to substitute for Fe. Understanding the distribution of minor and trace elements in Fe disulfides in coal has important implications for their availability to the environment through coal mining and use, as well as for potential reduction by coal preparation, and for delineating diagenetic compositional changes throughout and after coal formation.
ERIC Educational Resources Information Center
Whitmore, Kay R.
This paper argues for the participation and partnership of diverse elements in the community in order to achieve the goals of educational reform, and especially to encourage academic achievement among minority students. In a speech before the Forum '88 conference of the National Action Council for Minorities in Engineering, the cooperative…
Study of the influence of platinum, palladium and rhodium on duckweed (Lemna minor).
Bednarova, Ivana; Mikulaskova, Hana; Havelkova, Barbora; Strakova, Lenka; Beklova, Miroslava; Sochor, Jiri; Hynek, David; Adam, Vojtech; Kizek, Rene
2014-01-01
Road traffic pollutants and the residues of cytostatics that are widely used in anti-cancer therapy are a significant sources of platinum group elements (PGE; Pt, Pd and Rh) in environment. These metals can migrate into sewage and thus pollute surface waters. The purpose of our study was to evaluate the effect of PtCl4 on the antioxidant and enzymatic activity of duckweed (Lemna minor), a bioindicator of the aquatic environment. The study was performed using a 7-day conventional test based on the OECD 221 (CSN EN ISO 20079)--Lemna sp. Growth Inhibition Test. We also conducted a microbiotest to analyse the effects of PtC4, PdCl2 and RhCl3 on the morphology and vegetative growth of colonies of this plant and compared their inhibitory effects during the microbiotest. We observed inhibition of colony growth and clear morphological changes. Antioxidant and enzymatic activities increased with platinum doses increased. The 168hEC50 of PtCl4 was 12.16 μM (95% confidence interval = 9.88-14.44) and the 168hEC50 of PdCl2 was 50.39 (95% confidence interval = 23.83-76.96). The greatest inhibition of growth by RhCl3 was observed at 25 μM. The obtained results suggest that L. minor phytotoxicity tests should be widely used in the biomonitoring.
NASA Astrophysics Data System (ADS)
Pingitore, N. E., Jr.; Clague, J. W.; Gorski, D.
2014-12-01
The Round Top Mountain peraluminous rhyolite, exposed at the surface in Sierra Blanca, Hudspeth County, west Texas, USA, is enriched in yttrium and heavy rare earth elements (YHREEs). Other potentially valuable elements in the deposit include Be, Li, U, Th, Sn, F, Nb, and Ta. Texas Rare Earth Resources Corp. proposes to extract the YHREEs from the host mineral variety yttrofluorite by inexpensive heap leaching with dilute sulfuric acid, which also releases some of the Be, Li, U, F, and Th from other soluble minor minerals. Data: Feldspars and quartz comprise 90-95% of the rhyolite, with pheonocrysts of up to 250 microns set in an aphanitic matrix that hosts the typically sub-micron target yttrofluorite. Reverse circulation cuttings from some 100 drill holes, two drill cores, and outcrop and trench observations suggest striking physical homogeneity through this billion-plus ton surface-exposed laccolith, about 1200 feet high and a mile in diameter (375 x 1600 m). Gray to pink, and other minor hues, color variation derives from magnetite—hematite redox reaction. Plots of Y, 13 REEs, U, Th, and Nb analyses from over 1500 samples collected from 64 drill holes (color codes in figure) exhibit remarkably little variation in the concentration of these elements with geographic position or depth within the laccolith. Importance: Uniform mineralization grades help insure against the mining production surprises often associated with vein deposits and heterogeneous open pit deposits. At Round Top, mine feedstock can be relatively constant over the life of the mine (multiple decades), so the mechanical mining process can be optimized early on and not need expensive alterations later. Likewise, the chemical and physical parameters of the heap leach can be perfected. The sensitive and expensive process of extraction of elements and element groups from the pregnant leach solution and purification also can be optimized. Origin: The remarkable homogeneity of the YHREE distribution through the laccolith suggest YHREE and associated mineralization from a late-stage fluorine vapor generated within the magma in situ, rather than from injection of a F-rich fluid from an external source. The micron-scale cavities that produce up to 5% original porosity in the rhyolite may be nano-analogues of the cavities associated with granite pegmatites.
NASA Astrophysics Data System (ADS)
Ding, T.; Ma, D.; Lu, J.; Zhang, R.
2017-12-01
Huangshaping polymetallic deposit, located in southern Hunan Province, China, hosts abundant W-Mo-Pb-Zn mineralization which linked with the skarn system located between late Mesozoic high-K calc-alkaline to shoshonitic granitoids and the Carboniferous carbonate in this deposit. In this study, concentrations of trace and minor elements of the magnetites from different skarn stages are obtained by in situ LA-ICP-MS analysis, in order to further understand the polymetallic mineralization processes within this deposit. The generally high concentrations of spinel elements, including Mg, Al, Ti, Mn, V, Cr, Co, Ni, Ga, Ge, and Sn, in all magnetites from this deposit suggest that these elements are incorporated into magnetite lattice by substituting Fe3+ and/or Fe2+. However, the various concentrations of Na, Si, K, Ca, and W elements in magnetites, combining the abnormal time-resolved analytical signals of LA-ICP-MS analyses, suggest that these elements are significantly affected by the fluid inclusions in magnetites. Two groups of magnetites can be further distinguished based on their trace and minor elements concentrations: Group-1 magnetites, including those in medium grain garnets and calcite, have obvious lower Na, Si, K, Ca, Sn, W, but higher Mg, Al, Ti, V, Co, Ni, Zn concentrations compared with Group-2 magnetites, which including those in coarse grain garnets, tremolite, and bulk magnetite ores. This suggests that the hydrothermal fluids where Group-2 magnetites precipitated are evolved magmatic fluids which have undergone the crystal fractionation during the early skarn stages (eg. Garnet and tremolite), the high Na, Si, K, and Ca in the hydrothermal fluids probably result from the dissolution of the host rocks, such as limestone, sandstone, and evaporite horizons in this deposit. However, the Group-1 magnetites probably precipitated in the hydrothermal fluids with low salinity, which result the low Na, Si, K, and Ca in these magnitites. Furthermore, these fluids might have undergone large scale circulation, the extraction from Zn-rich metamorphic basement and Mg, Al-rich strata probably have provided abundant Mg, Al, Zn in the hydrothermal fluids where Group-1 magnetites precipitated. As a conclusion, this study suggests that the compositions of magnetites can be the proxies of ore genesis.
Lee, Haofu; Nguyen, Alan; Hong, Christine; Hoang, Paul; Pham, John; Ting, Kang
2017-01-01
Introduction The aims of this study were to evaluate the effects of rapid palatal expansion on the craniofacial skeleton of a patient with unilateral cleft lip and palate (UCLP) and to predict the points of force application for optimal expansion using a 3-dimensional finite element model. Methods A 3-dimensional finite element model of the craniofacial complex with UCLP was generated from spiral computed tomographic scans with imaging software (Mimics, version 13.1; Materialise, Leuven, Belgium). This model was imported into the finite element solver (version 12.0; ANSYS, Canonsburg, Pa) to evaluate transverse expansion forces from rapid palatal expansion. Finite element analysis was performed with transverse expansion to achieve 5 mm of anterolateral expansion of the collapsed minor segment to simulate correction of the anterior crossbite in a patient with UCLP. Results High-stress concentrations were observed at the body of the sphenoid, medial to the orbit, and at the inferior area of the zygomatic process of the maxilla. The craniofacial stress distribution was asymmetric, with higher stress levels on the cleft side. When forces were applied more anteriorly on the collapsed minor segment and more posteriorly on the major segment, there was greater expansion of the anterior region of the minor segment with minimal expansion of the major segment. Conclusions The transverse expansion forces from rapid palatal expansion are distributed to the 3 maxillary buttresses. Finite element analysis is an appropriate tool to study and predict the points of force application for better controlled expansion in patients with UCLP. PMID:27476365
Lee, Haofu; Nguyen, Alan; Hong, Christine; Hoang, Paul; Pham, John; Ting, Kang
2016-08-01
The aims of this study were to evaluate the effects of rapid palatal expansion on the craniofacial skeleton of a patient with unilateral cleft lip and palate (UCLP) and to predict the points of force application for optimal expansion using a 3-dimensional finite element model. A 3-dimensional finite element model of the craniofacial complex with UCLP was generated from spiral computed tomographic scans with imaging software (Mimics, version 13.1; Materialise, Leuven, Belgium). This model was imported into the finite element solver (version 12.0; ANSYS, Canonsburg, Pa) to evaluate transverse expansion forces from rapid palatal expansion. Finite element analysis was performed with transverse expansion to achieve 5 mm of anterolateral expansion of the collapsed minor segment to simulate correction of the anterior crossbite in a patient with UCLP. High-stress concentrations were observed at the body of the sphenoid, medial to the orbit, and at the inferior area of the zygomatic process of the maxilla. The craniofacial stress distribution was asymmetric, with higher stress levels on the cleft side. When forces were applied more anteriorly on the collapsed minor segment and more posteriorly on the major segment, there was greater expansion of the anterior region of the minor segment with minimal expansion of the major segment. The transverse expansion forces from rapid palatal expansion are distributed to the 3 maxillary buttresses. Finite element analysis is an appropriate tool to study and predict the points of force application for better controlled expansion in patients with UCLP. Copyright © 2016 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.
Chemistry of rocks and soils at Meridiani Planum from the Alpha Particle X-ray Spectrometer.
Rieder, R; Gellert, R; Anderson, R C; Brückner, J; Clark, B C; Dreibus, G; Economou, T; Klingelhöfer, G; Lugmair, G W; Ming, D W; Squyres, S W; d'Uston, C; Wänke, H; Yen, A; Zipfel, J
2004-12-03
The Alpha Particle X-ray Spectrometer on the Opportunity rover determined major and minor elements of soils and rocks in Meridiani Planum. Chemical compositions differentiate between basaltic rocks, evaporite-rich rocks, basaltic soils, and hematite-rich soils. Although soils are compositionally similar to those at previous landing sites, differences in iron and some minor element concentrations signify the addition of local components. Rocky outcrops are rich in sulfur and variably enriched in bromine relative to chlorine. The interaction with water in the past is indicated by the chemical features in rocks and soils at this site.
Cotta, Aloisio J. B.; Enzweiler, Jacinta; Wilson, Stephen A.; Perez, Carlos A.; Nardy, Antonio J. R.; Larizzatti, Joao H.
2007-01-01
Reference materials (RM) are required for quantitative analyses and their successful use is associated with the degree of homogeneity, and the traceability and confidence limits of the values established by characterisation. During the production of a RM, the chemical characterisation can only commence after it has been demonstrated that the material has the required level of homogeneity. Here we describe the preparation of BRP-1, a proposed geochemical reference material, and the results of the tests to evaluate its degree of homogeneity between and within bottles. BRP-1 is the first of two geochemical RM being produced by Brazilian institutions in collaboration with the United States Geological Survey (USGS) and the International Association of Geoanalysts (IAG). Two test portions of twenty bottles of BRP-1 were analysed by wavelength dispersive-XRF spectrometry and major, minor and eighteen trace elements were determined. The results show that for most of the investigated elements, the units of BRP-1 were homogeneous at conditions approximately three times more rigorous than those strived for by the test of “sufficient homogeneity”. Furthermore, the within bottle homogeneity of BRP-1 was evaluated using small beam (1 mm2) synchrotron radiation XRF spectrometry and, for comparison, the USGS reference materials BCR-2 and GSP-2 were also evaluated. From our data, it has been possible to assign representative minimum masses for some major constituents (1 mg) and for some trace elements (1-13 mg), except Zr in GSP-2, for which test portions of 74 mg are recommended.
An Analysis of Educational Policy: Implications for Minority Community Concerns.
ERIC Educational Resources Information Center
Harris, J. John, III; Ogle, Terry
The paper presents a detailed overview of educational policymaking and discusses the need for minority groups to be involved in policy formation. The first section describes the distinguishing characteristics of the main elements of the functions of administration and policymaking process. The second section examines the following three models of…
Creating a Campus Climate That Supports Academic Excellence.
ERIC Educational Resources Information Center
Adams, Howard G.
This paper discusses the campus climate as a critical element in the academic development of college students, with emphasis on minority and women students pursuing engineering and other technical degrees. Reforming the campus climate to make it more receptive to minority and women students requires: (1) a clear mandate from top administrators to…
Daily minority stress and affect among gay and bisexual men: A 30-day diary study.
Eldahan, Adam I; Pachankis, John E; Jonathon Rendina, H; Ventuneac, Ana; Grov, Christian; Parsons, Jeffrey T
2016-01-15
This study examined the time-variant association between daily minority stress and daily affect among gay and bisexual men. Tests of time-lagged associations allow for a stronger causal examination of minority stress-affect associations compared with static assessments. Multilevel modeling allows for comparison of associations between minority stress and daily affect when minority stress is modeled as a between-person factor and a within-person time-fluctuating state. 371 gay and bisexual men in New York City completed a 30-day daily diary, recording daily experiences of minority stress and positive affect (PA), negative affect (NA), and anxious affect (AA). Multilevel analyses examined associations between minority stress and affect in both same-day and time-lagged analyses, with minority stress assessed as both a between-person factor and a within-person state. Daily minority stress, modeled as both a between-person and within-person construct, significantly predicted lower PA and higher NA and AA. Daily minority stress also predicted lower subsequent-day PA and higher subsequent-day NA and AA. Self-report assessments and the unique sample may limit generalizability of this study. The time-variant association between sexual minority stress and affect found here substantiates the basic tenet of minority stress theory with a fine-grained analysis of gay and bisexual men's daily experience. Time-lagged effects suggest a potentially causal pathway between minority stress as a social determinant of mood and anxiety disorder symptoms among gay and bisexual men. When modeled as both a between-person factor and within-person state, minority stress demonstrated expected patterns with affect. Copyright © 2015 Elsevier B.V. All rights reserved.
Daily Minority Stress and Affect among Gay and Bisexual Men: A 30-day Diary Study
Eldahan, Adam I.; Pachankis, John E.; Rendina, H. Jonathon; Ventuneac, Ana; Grov, Christian; Parsons, Jeffrey T.
2015-01-01
Background This study examined the time-variant association between daily minority stress and daily affect among gay and bisexual men. Tests of time-lagged associations allow for a stronger causal examination of minority stress-affect associations compared with static assessments. Multilevel modeling allows for comparison of associations between minority stress and daily affect when minority stress is modeled as a between-person factor and a within-person time-fluctuating state. Methods 371 gay and bisexual men in New York City completed a 30-day daily diary, recording daily experiences of minority stress and positive affect (PA), negative affect (NA), and anxious affect (AA). Multilevel analyses examined associations between minority stress and affect in both same-day and time-lagged analyses, with minority stress assessed as both a between-person factor and a within-person state. Results Daily minority stress, modeled as both a between-person and within-person construct, significantly predicted lower PA and higher NA and AA. Daily minority stress also predicted lower subsequent-day PA and higher subsequent-day NA and AA. Limitations Self-report assessments and the unique sample may limit generalizability of this study. Conclusions The time-variant association between sexual minority stress and affect found here substantiates the basic tenet of minority stress theory with a fine-grained analysis of gay and bisexual men’s daily experience. Time-lagged effects suggest a potentially causal pathway between minority stress as a social determinant of mood and anxiety disorder symptoms among gay and bisexual men. When modeled as both a between-person factor and within-person state, minority stress demonstrated expected patterns with affect. PMID:26625095
NASA Astrophysics Data System (ADS)
Dyar, M. D.; Nelms, M.; Breves, E. A.
2012-12-01
Laser-induced breakdown spectrometer (LIBS), as implemented on the ChemCam instrument on Mars Science Lab and the proposed New Frontiers SAGE mission to Venus, can analyze elements from H to Pb from up to 7m standoff. This study examines the capabilities of LIBS to analyze H, O, B, Be, and Li under conditions simulating Earth, the Moon, and Mars. Of these, H is a major constituent of clay minerals and a key indicator of the presence of water. Its abundance in terrestrial materials ranges from 0 ppm up to 10's of wt.% H2O in hydrated sulfates and clays, with prominent emission lines occurring ca. 656.4 nm. O is an important indicator of atmospheric and magmatic coevolution, and has lines ca. 615.8, 656.2, 777.6, and 844.8 nm. Unfortunately there are very few geological samples from which O has been directly measured, but stoichiometry suggests that O varies from ca. 0 wt.% in sulfides to 21% in ferberite, 32% in ilmenite, 42% in amphiboles, 53% in quartz, 63% in melanterite, and 71% in epsomite. Li (lines at 413.3, 460.4, and 670.9 nm in vacuum), B (412.3 nm), and Be (313.1 nm) are highly mobile elements and key indicators of interaction with water. Local atmospheric composition and pressure significantly influence LIBS plasma intensity because the local atmosphere and the breakdown products from the atmospheric species interact with the ablated surface material in the plasma. Measurement of light elements with LIBS requires that spectra be acquired under conditions matching the remote environment. LIBS is critically dependent on the availability of well characterized, homogeneous reference materials that are closely matched in matrix (composition and structure) to the sample being studied. In modern geochemistry, analyses of most major, minor, and trace elements are routinely made. However, quantitative determination of light element concentrations in geological specimens still represents a major analytical challenge. Thus standards for which hydrogen, oxygen, and other light elements are directly measured are nearly nonexistent in the 1-2 g quantities needed for LIBS analyses. For this study, we have obtained two sample suites that provide calibrations needed for accurate analyses of H, O, B, Be, and Li in geological samples. The first suite of 11 samples was analyzed for oxygen by fast neutron activation analysis. The second suite includes 11 gem-quality minerals representing the major rock-forming species for B, Li, and Be-rich parageneses. Light elements were directly analyzed using a combination of EMPA, XRF, ion microprobe, uranium extraction, proton-induced gamma-ray emission (PIGE), and prompt gamma-ray neutron activation analysis (PGNAA). LIBS spectra were acquired at Mount Holyoke College under air, vacuum, and CO2 to simulate terrestrial, lunar, and martian environments. Spectra were then used to develop three separate calibration models (one for each environment), enabling LIBS characterization of light elements using multivariate analyses. Results show that when direct analyses of H, O, Li, B, and Be are used rather than LOI results, inferred, or indirectly calculated values, optimal root mean squared errors of prediction result. We are actively adding samples to these calibration suites, and we expect that prediction errors (accuracies) of <1wt% for these elements are possible.
NASA Astrophysics Data System (ADS)
Stefanovsky, S. V.; Stefanovsky, O. I.; Kadyko, M. I.; Nikonov, B. S.
2018-03-01
Sodium aluminum (iron) phosphate glass ceramics containing of up to 20 wt.% rare earth (RE) oxides simulating pyroprocessing waste were produced by melting at 1250 °C followed by either quenching or slow cooling to room temperature. The iron-free glass-ceramics were composed of major glass and minor phosphotridymite and monazite. The iron-bearing glass-ceramics were composed of major glass and minor monazite and Na-Al-Fe orthophosphate at low waste loadings (5-10 wt.%) and major orthophosphate and minor monazite as well as interstitial glass at high waste loadings (15-20 wt.%). Slowly cooled samples contained higher amount of crystalline phases than quenched ones. Monazite is major phase for REs. Leach rates from the materials of major elements (Na, Al, Fe, P) are 10-5-10-7 g cm-2 d-1, RE elements - lower than 10-5 g cm-2 d-1.
The Resurrection of Laplace’s Method of Initial Orbit Determination
1983-01-17
and retrograde, at least one-third of that of a main belt asteroid. Presumably it was the strange motion that kept the Minor Planet Center from...main- belt minor planets. For an Earth-approaching asteroid one needs an element set for next month. Both 1982HS and 1982SA were discovered by our...pseudo-observations good to 1". A. 1982HS and 1982SA Both of these are inner main- belt , high inclination, high eccen- tricity minor planets. Since
Bishop, Janice L; Englert, Peter A J; Patel, Shital; Tirsch, Daniela; Roy, Alex J; Koeberl, Christian; Böttger, Ute; Hanke, Franziska; Jaumann, Ralf
2014-12-13
Surface sediments at Lakes Fryxell, Vanda and Brownworth in the Antarctic Dry Valleys (ADV) were investigated as analogues for the cold, dry environment on Mars. Sediments were sampled from regions surrounding the lakes and from the ice cover on top of the lakes. The ADV sediments were studied using Raman spectra of individual grains and reflectance spectra of bulk particulate samples and compared with previous analyses of subsurface and lakebottom sediments. Elemental abundances were coordinated with the spectral data in order to assess trends in sediment alteration. The surface sediments in this study were compared with lakebottom sediments (Bishop JL et al. 2003 Int. J. Astrobiol. 2, 273-287 (doi:10.1017/S1473550403001654)) and samples from soil pits (Englert P et al. 2013 In European Planetary Science Congress, abstract no. 96; Englert P et al. 2014 In 45th Lunar and Planetary Science Conf., abstract no. 1707). Feldspar, quartz and pyroxene are common minerals found in all the sediments. Minor abundances of carbonate, chlorite, actinolite and allophane are also found in the surface sediments, and are similar to minerals found in greater abundance in the lakebottom sediments. Surface sediment formation is dominated by physical processes; a few centimetres below the surface chemical alteration sets in, whereas lakebottom sediments experience biomineralization. Characterizing the mineralogical variations in these samples provides insights into the alteration processes occurring in the ADV and supports understanding alteration in the cold and dry environment on Mars. © 2014 The Author(s) Published by the Royal Society. All rights reserved.
Estrada, Mica; Woodcock, Anna; Hernandez, Paul R.; Schultz, P. Wesley
2010-01-01
Students from several ethnic minority groups are underrepresented in the sciences, such that minority students more frequently drop out of the scientific career path than non-minority students. Viewed from a perspective of social influence, this pattern suggests that minority students do not integrate into the scientific community at the same rate as non-minority students. Kelman (1958, 2006) describes a tripartite integration model of social influence (TIMSI) by which a person orients to a social system. To test if this model predicts integration into the scientific community, we conducted analyses of data from a national panel of minority science students. A structural equation model framework showed that self-efficacy (operationalized consistent with Kelman’s ‘rule-orientation’) predicted student intentions to pursue a scientific career. However, when identification as a scientist and internalization of values are added to the model, self-efficacy becomes a poorer predictor of intention. Additional mediation analyses support the conclusion that while having scientific self-efficacy is important, identifying with and endorsing the values of the social system reflect a deeper integration and more durable motivation to persist as a scientist. PMID:21552374
NASA Astrophysics Data System (ADS)
Lezzerini, Marco; Antonelli, Fabrizio; Gallello, Gianni; Ramacciotti, Mirco; Parodi, Luca; Alberti, Antonio; Pagnotta, Stefano; Legnaioli, Stefano; Palleschi, Vincenzo
2017-05-01
The aim of this study is to investigate the provenance of marbles used as architectural elements (bases, shafts and capitals of columns) for building the internal spiral staircase of the medieval bell tower of St. Nicholas Church at Pisa, Italy. Accordingly, the 45 collected marble samples have been analysed by optical microscopy, X-ray powder diffraction and mass spectroscopy for carbon and oxygen stable isotope ratio analysis; additionally, SEM-EDS analysis have been performed to complement data about accessory minerals. By comparison with literature data on the main sources of the white Mediterranean marbles used in ancient times, the results show that the analysed samples are mainly white crystalline marbles from Carrara (Italy) and, subordinately, from other Tuscan and Eastern Mediterranean quarrying areas. In fact, Mt. Pisano and Campiglia M.ma (Tuscany, Italy) and Marmara (Turkey), Paros, Mt. Penteli, Thasos (Greece) are minor sources. The other coloured stones identified on the strength of their macroscopic features are quartzites from Mt. Pisano area and granitoids from Sardinia and Island of Elba (Italy). Occasionally, a very limited number of architectonical elements made up of Acquabona limestone from Rosignano Marittimo (Livorno, Italy), red limestone with ammonites (the so-called "Rosso Ammonitico") and black limestone belonging to the Tuscan Nappe sequence, outcropping at northwest of Pisa in the nearby Monti d'Oltre Serchio area, are present.
Philip, Jessica Elizabeth; Shahid, Muhammad; Prathapachandra Kurup, M R; Velayudhan, Mohanan Puzhavoorparambil
2017-10-01
Two chromone hydrazone ligands HL 1 and HL 2 were synthesized and characterized by elemental analyses, IR, 1 H NMR & 13 C NMR, electronic absorption and mass spectra. The reactions of the chromone hydrazones with transition metals such as Ni, Cu, and Zn (II) salts of acetate afforded mononuclear metal complexes. Characterization and structure elucidation of the prepared chromone hydrazone metal (II) complexes were done by elemental, IR, electronic, EPR spectra and thermo gravimetric analyses as well as conductivity and magnetic susceptibility measurements. The spectroscopic data showed that the ligand acts as a mono basic bidentate with coordination sites are azomethine nitrogen and hydrazonic oxygen, and they exhibited distorted geometry. The biological studies involved antidiabetic activity i.e. enzyme inhibition of α-amylase and α-glucosidase, Calf Thymus - DNA (CT-DNA) interaction and molecular docking. Potential capacity of synthesized compounds to inhibit the α-amylase and α-glucosidase activity was assayed whereas DNA interaction studies were carried out with the help UV-Vis absorption titration and viscosity method. The docking studies of chromone hydrazones show that they are minor groove binders. Complexes were found to be good DNA - intercalates. Chromone hydrazones and its transition metal complexes have shown comparable antidiabetic activity with a standard drug acarbose. Copyright © 2017 Elsevier B.V. All rights reserved.
Analysing Language Education Policy for China's Minority Groups in Its Entirety
ERIC Educational Resources Information Center
Feng, Anwei; Sunuodula, Mamtimyn
2009-01-01
Two main bodies of literature are identifiable in minority education policy studies in China. Many adopt a descriptive approach to examining policy documents and general outcomes in their historical contexts while others focus on evaluating preferential policies made to address inequality issues in minority education. In most discussions,…
The Ethnic Minority Achievement Grant: A Critical Analysis
ERIC Educational Resources Information Center
Tikly, Leon; Osler, Audrey; Hill, John
2005-01-01
This article critically analyses the extent to which the Ethnic Minority Achievement Grant (EMAG) has been successful in meeting its core objective of raising the achievement of minority ethnic groups who are at risk of underachieving. The article provides an historical analysis of the Grant, sets the Grant within the context of the Labour…
Alpha proton x ray spectrometer
NASA Technical Reports Server (NTRS)
Rieder, Rudi; Waeke, H.; Economou, T.
1994-01-01
Mars Pathfinder will carry an alpha-proton x ray spectrometer (APX) for the determination of the elemental chemical composition of Martian rocks and soils. The instrument will measure the concentration of all major and some minor elements, including C, N, and O at levels above typically 1 percent.
ERIC Educational Resources Information Center
Hamlin, Larry
This document is a student manual for a general mechanical repair course. Following a list of common essential elements of trade and industrial education, the manual is divided into three sections. The first section, on minor automotive maintenance, contains 13 units: automotive shop safety; engine principles; fuel system operation and repair;…
ERIC Educational Resources Information Center
Hamlin, Larry
This document contains the competency test package for three sections of a general mechanical repair course: minor automotive maintenance, small engine mechanics, and welding. Following a list of the common essential elements for trade and industrial education, competency tests for the three sections are provided. Each test includes unit name,…
Minor planets and related objects. XIX - Shape and pole orientation of /39/ Laetitia
NASA Technical Reports Server (NTRS)
Sather, R. E.
1976-01-01
Results are reported for analyses of UBV photoelectric photometric data and light curves of the asteroid Laetitia. The pole orientation is determined using a technique for reducing the scatter in the magnitude-phase relation. No significant variations in color are found over the surface, and the light curves are found to indicate topographic elements (peaks, scarps, or depressions) approximately 10 km in radius. It is shown that the light-curve amplitudes as well as the wide scatter in observed magnitude and phase relation can be explained by a triaxial ellipsoidal figure with a dimensional ratio of about 15:9:5. It is concluded that the size, shape, and composition of this asteroid are highly suggestive of a major collisional fragment from a substantially more massive differentiated parent body.
NASA Astrophysics Data System (ADS)
Caterina, Ingoglia; Maurizio, Triscari; Giuseppe, Sabatino
The archaeological site in Via La Farina, Block P, in Messina, is unique in many ways, due also to the high quantity of samples of iron slag. The slag was examined to identify the production centres of such materials, and, after characterization, was compared to similar material, exclusively for product typology, from different archaeological sites in the province of Messina, situated in the Peloritani Mountains (Messina city, S. Marco d'Alunzio, Milazzo, Francavilla di Sicilia, Novara di Sicilia as well as the archaeological site of Halaesa, near Tusa). Mineralogical characterization of the phases carried out by X-ray diffractometry (XRD) and Rietveld data elaboration, morphological study of slag findings and a semi-quantitative analysis by scanning electronic microscope (SEM+EDX) were performed. A chemical investigation was carried out by electron probe micro analysis (EPMA), to determine major element,. Minor and trace elements were determined by LA-ICP-MS. All the examined slag is related to iron metallurgy, and, in the case of Via La Farina, there is firm archaeological evidence pinpointing to smelting activity.
National Coal Quality Inventory (NACQI)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Robert Finkelman
2005-09-30
The U.S. Geological Survey (USGS) conducted the National Coal Quality Inventory (NaCQI) between 1999 and 2005 to address a need for quality information on coals that will be mined during the next 20-30 years. Collaboration between the USGS, State geological surveys, universities, coal burning utilities, and the coal mining industry plus funding support from the Electric Power Research Institute (EPRI) and the U.S. Department of Energy (DOE) permitted collection and submittal of coal samples for analysis. The chemical data (proximate and ultimate analyses; major, minor and trace element concentrations) for 729 samples of raw or prepared coal, coal associated shale,more » and coal combustion products (fly ash, hopper ash, bottom ash and gypsum) from nine coal producing States are included. In addition, the project identified a new coal reference analytical standard, to be designated CWE-1 (West Elk Mine, Gunnison County, Colorado) that is a high-volatile-B or high-volatile-A bituminous coal with low contents of ash yield and sulfur, and very low, but detectable contents of chlorine, mercury and other trace elements.« less
Multielemental analyses of isomorphous Indian garnet gemstones by XRD and external pixe techniques.
Venkateswarulu, P; Srinivasa Rao, K; Kasipathi, C; Ramakrishna, Y
2012-12-01
Garnet gemstones were collected from parts of Eastern Ghats geological formations of Andhra Pradesh, India and their gemological studies were carried out. Their study of chemistry is not possible as they represent mixtures of isomorphism nature, and none of the individual specimens indicate independent chemistry. Hence, non-destructive instrumental methodology of external PIXE technique was employed to understand their chemistry and identity. A 3 MeV proton beam was employed to excite the samples. In the present study geochemical characteristics of garnet gemstones were studied by proton induced X-ray emission. Almandine variety of garnet is found to be abundant in the present study by means of their chemical contents. The crystal structure and the lattice parameters were estimated using X-Ray Diffraction studies. The trace and minor elements are estimated using PIXE technique and major compositional elements are confirmed by XRD studies. The technique is found very useful in characterizing the garnet gemstones. The present work, thus establishes usefulness and versatility of the PIXE technique with external beam for research in Geo-scientific methodology. Copyright © 2012 Elsevier Ltd. All rights reserved.
Crystal Field Effects and Siderophile Element Partitioning: Implications for Mars HSE Geochemistry
NASA Technical Reports Server (NTRS)
Jones, John H.; Malavergne, V.; Neal, C. R.
2007-01-01
Analyses of martian (SNC) meteorites indicate that Pt abundances do not vary much compared to other highly siderophile elements (HSE). Therefore, Jones et al. [1] inferred that D(Pt) during basalt petrogenesis was of order unity. This inference was at odds with previously published experiments that gave a D(sub ol/liq) for Pt of approx. 0.01 [2]. Because olivine is likely to be an important constituent of any reasonable martian mantle, the implication of these findings is that minor minerals must have D(Pt) much greater than 1, which seemed improbable. However, not only did the SNC evidence point to a D(sub ol/liq) approx. equal to 1, but so did plots of D(sub ol/liq) vs. ionic radius (Onuma diagram). The ionic radius of Pt(2+) suggested that D(sub ol/liq) for Pt was of order unity, in agreement with the inferences from SNC meteorites. New experiments have failed to detect measurable Pt in olivine, even at high oxygen fugacities [3]. Therefore, some other parameter, other than ionic charge and radius, must hold sway during olivine liquid partitioning of Pt.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Butterworth, A.L.; Becker, N.; Gainsforth, Z.
2012-03-13
Quantification of synchrotron XRF analyses is typically done through comparisons with measurements on the NIST SRM 1832/1833 thin film standards. Unfortunately, these standards are inhomogeneous on small scales at the tens of percent level. We are synthesizing new homogeneous multilayer standards using the Atomic Layer Deposition technique and characterizing them using multiple analytical methods, including ellipsometry, Rutherford Back Scattering at Evans Analytical, Synchrotron X-ray Fluorescence (SXRF) at Advanced Photon Source (APS) Beamline 13-ID, Synchrotron X-ray Absorption Spectroscopy (XAS) at Advanced Light Source (ALS) Beamlines 11.0.2 and 5.3.2.1 and by electron microscopy techniques. Our motivation for developing much-needed cross-calibration of synchrotronmore » techniques is borne from coordinated analyses of particles captured in the aerogel of the NASA Stardust Interstellar Dust Collector (SIDC). The Stardust Interstellar Dust Preliminary Examination (ISPE) team have characterized three sub-nanogram, {approx}1{micro}m-sized fragments considered as candidates to be the first contemporary interstellar dust ever collected, based on their chemistries and trajectories. The candidates were analyzed in small wedges of aerogel in which they were extracted from the larger collector, using high sensitivity, high spatial resolution >3 keV synchrotron x-ray fluorescence spectroscopy (SXRF) and <2 keV synchrotron x-ray transmission microscopy (STXM) during Stardust ISPE. The ISPE synchrotron techniques have complementary capabilities. Hard X-ray SXRF is sensitive to sub-fg mass of elements Z {ge} 20 (calcium) and has a spatial resolution as low as 90nm. X-ray Diffraction data were collected simultaneously with SXRF data. Soft X-ray STXM at ALS beamline 11.0.2 can detect fg-mass of most elements, including cosmochemically important oxygen, magnesium, aluminum and silicon, which are invisible to SXRF in this application. ALS beamline 11.0.2 has spatial resolution better than 25 nm. Limiting factors for Stardust STXM analyses were self-imposed limits of photon dose due to radiation damage concerns, and significant attenuation of <1500 eV X-rays by {approx}80{micro}m thick, {approx}25 mg/cm{sup 3} density silica aerogel capture medium. In practice, the ISPE team characterized the major, light elements using STXM (O, Mg, Al, Si) and the heavier minor and trace elements using SXRF. The two data sets overlapped only with minor Fe and Ni ({approx}1% mass abundance), providing few quantitative cross-checks. New improved standards for cross calibration are essential for consortium-based analyses of Stardust interstellar and cometary particles, IDPs. Indeed, they have far reaching application across the whole synchrotron-based analytical community. We have synthesized three ALD multilayers simultaneously on silicon nitride membranes and silicon and characterized them using RBS (on Si), XRF (on Si{sub 3}N{sub 4}) and STXM/XAS (holey Si{sub 3}N{sub 4}). The systems we have started to work with are Al-Zn-Fe and Y-Mg-Er. We have found these ALD multi-layers to be uniform at {micro}m- to nm scales, and have found excellent consistency between four analytical techniques so far. The ALD films can also be used as a standard for e-beam instruments, eg., TEM EELS or EDX. After some early issues with the consistency of coatings to the back-side of the membrane windows, we are confident to be able to show multi-analytical agreement to within 10%. As the precision improves, we can use the new standards to verify or improve the tabulated cross-sections.« less
SEASONAL MONITORING OF ELEMENTS AT THREE CONSTRUCTED TREATMENT WETLANDS: 1999-2001
A suite of major, minor, and trace elements in sediment, pore water, and overlying water were monitored during winter and summer over a three year period at three different types of constructed treatment wetlands to evaluate their efficacy with season. Acid-volatile sulfide (AVS)...
ERIC Educational Resources Information Center
Baysu, Gülseli; Celeste, Laura; Brown, Rupert; Verschueren, Karine; Phalet, Karen
2016-01-01
Can perceptions of equal treatment buffer the negative effects of threat on the school success of minority students? Focusing on minority adolescents from Turkish and Moroccan heritage in Belgium (M[subscript age] = 14.5; N = 735 in 47 ethnically diverse schools), multilevel mediated moderation analyses showed: (a) perceived discrimination at…
ERIC Educational Resources Information Center
Kulyk, Volodymyr
2013-01-01
This article analyses school systems for two of Ukraine's minorities, the Hungarians and the Crimean Tatars with the aim of assessing their success in promoting ethnocultural identity and social integration of the minority youth. I demonstrate that the exclusive instruction in Hungarian ensures the reproduction of group language knowledge and…
Body Image Concerns of Gay Men: The Roles of Minority Stress and Conformity to Masculine Norms
ERIC Educational Resources Information Center
Kimmel, Sara B.; Mahalik, James R.
2005-01-01
The authors hypothesized that gay men's experiences of minority stress and their conformity to masculine norms would be associated with increased body image dissatisfaction and masculine body ideal distress. For this cross-sectional study, 357 gay males completed a Web-based survey, and 2 multiple regression analyses indicated that minority stress…
Leventhal, J.S.; Hosterman, J.W.
1982-01-01
Core samples of Devonian shales from five localities in the Appalachian basin have been analyzed chemically and mineralogically. The amounts of major elements are similar; however, the minor constituents, organic C, S, phosphate and carbonate show ten-fold variations in amounts. Trace elements Mo, Ni, Cu, V, Co, U, Zn, Hg, As and Mn show variations in amounts that can be related to the minor constituents. All samples contain major amounts of quartz, illite, two types of mixed-layer clays, and chlorite in differing quantities. Pyrite, calcite, feldspar and kaolinite are also present in many samples in minor amounts. Dolomite, apatite, gypsum, barite, biotite and marcasite are present in a few samples in trace amounts. Trace elements listed above are strongly controlled by organic C with the exception of Mn which is associated with carbonate minerals. Amounts of organic C generally range from 3 to 6%, and S is in the range of 2-5%. Amounts of trace elements show the following general ranges in ppm (parts per million): Co, 20-40; Cu, 40-70; U, 10-40; As, 20-40; V, 150-300; Ni, 80-150; high values are as much as twice these values. The organic C was probably the concentrating agent, and the organic C and sulfide S together created an environment that immobilized and preserved these trace elements. Closely spaced samples showing an abrupt transition in color also show changes in organic C, S and trace-element contents. Several associations exist between mineral and chemical content. Pyrite and marcasite are the only minerals found to contain sulfide-S. In general, the illite-chlorite mixed-layer clay mineral shows covariation with organic C if calcite is not present. The enriched trace elements are not related to the clay types, although the clay and organic matter are intimately associated as the bulk fabric of the rock. ?? 1982.
NASA Astrophysics Data System (ADS)
Fernández-Olmo, Ignacio; Puente, Mariano; Montecalvo, Lucia; Irabien, Angel
2014-08-01
The bulk atmospheric deposition of the minor and trace elements As, Cd, Cr, Cu, Mn, Mo, Ni, Pb, Ti, V and Zn was investigated in Santander, a Northern Spanish coastal city. Bulk deposition samples were collected monthly for three years using a bottle/funnel device. Taking into account that heavy metals are bioavailable only in their soluble forms, water-soluble and water-insoluble fractions were evaluated separately for element concentration. The fluxes of the studied elements in the bulk deposition exhibited the following order: Zn > Mn ≫ Cu > Cr > Pb > V > Ni ≫ As > Mo > Cd. The fluxes of Zn and Mn were more than 10 times higher than those of the other elements, with maximum values of 554.5 and 334.1 μg m- 2 day- 1, respectively. Low solubilities (below 22%) were found for Cr, Ti and Pb, whereas the highest solubility was found for Zn (78%). With the exception of Cu, all of the studied metals in the water-soluble fraction of the atmospheric deposition showed seasonal dependence, due to the seasonal variability of precipitation. The enrichment factors (EFs) of Cu, Cd and Zn were higher than 100, indicating a clear anthropogenic origin. The EF of Mn (50) was below 100, but an exclusively industrial origin is suggested. Positive Matrix Factorisation (PMF) was used for the source apportionment of the studied minor and trace elements in the soluble fraction. Four factors were identified from PMF, and their chemical profiles were compared with those calculated from known sources that were previously identified in Santander Bay: two industrial sources, the first of which was characterised by Zn and Mn, which contributes 62.5% of the total deposition flux of the studied elements; a traffic source; and a maritime source. Zinc and Mn are considered to be the most characteristic pollutants of the studied area.
ERIC Educational Resources Information Center
Hamlin, Larry
This document contains a curriculum guide and lesson plans for a general mechanical repair course with three sections: minor automotive maintenance, small engine repair, and welding. The curriculum guide begins with a matrix that relates the lesson plans to essential elements of math, science, language arts, and social studies and to Texas…
Publications - RDF 2008-1 v. 1.0.1 | Alaska Division of Geological &
main content DGGS RDF 2008-1 v. 1.0.1 Publication Details Title: Major-oxide, minor-oxide, and trace , S.E., and Jing, L., 2008, Major-oxide, minor-oxide, and trace-element geochemical data from rocks and Birch Creek; Hope Creek; Idaho Creek; Major Oxides; McManus Creek; Montana Creek; Polar Creek; Pool
Assessment of Factors Resulting in Abuse Evaluations in Young Children with Minor Head Trauma
ERIC Educational Resources Information Center
Anderst, James D.
2008-01-01
Objective: The primary objective was to determine which of the examined factors prompted physicians to initiate a further abuse evaluation in young children with minor head injury. The recording of important historical elements in the charts of these patients was also evaluated. Methods: Charts of 349 children less than 3 years of age with minor…
NASA Technical Reports Server (NTRS)
Fijany, Amir (Inventor); Bejczy, Antal K. (Inventor)
1994-01-01
In a computer having a large number of single-instruction multiple data (SIMD) processors, each of the SIMD processors has two sets of three individual processor elements controlled by a master control unit and interconnected among a plurality of register file units where data is stored. The register files input and output data in synchronism with a minor cycle clock under control of two slave control units controlling the register file units connected to respective ones of the two sets of processor elements. Depending upon which ones of the register file units are enabled to store or transmit data during a particular minor clock cycle, the processor elements within an SIMD processor are connected in rings or in pipeline arrays, and may exchange data with the internal bus or with neighboring SIMD processors through interface units controlled by respective ones of the two slave control units.
Surface-active element effects on the shape of GTA, laser, and electron-beam welds
DOE Office of Scientific and Technical Information (OSTI.GOV)
Heiple, C.R.; Roper, J.R.; Stagner, R.T.
1983-03-01
Laser and electron-beam welds were passed across selenium-doped zones in 21-6-9 stainless steel. The depth/width (d/w) ratio of a defocused laser weld with a weld pool shape similar to a GTA weld increased by over 200% in a zone where 66 ppm selenium had been added. Smaller increases were observed in selenium-doped zones for a moderately defocused electron beam weld with a higher d/w ratio in undoped base metal. When laser or electron beam weld penetration was by a keyhole mechanism, no change in d/w ratio occurred in selenium-doped zones. The results confirm the surface-tension-driven fluid-flow model for the effectmore » of minor elements on GTA weld pool shape. Other experimental evidence bearing on the effect of minor elements on GTA weld penetration is summarized.« less
Boulyga, Sergei F; Heilmann, Jens; Prohaska, Thomas; Heumann, Klaus G
2007-10-01
A method for the direct multi-element determination of Cl, S, Hg, Pb, Cd, U, Br, Cr, Cu, Fe, and Zn in powdered coal samples has been developed by applying inductively coupled plasma isotope dilution mass spectrometry (ICP-IDMS) with laser-assisted introduction into the plasma. A sector-field ICP-MS with a mass resolution of 4,000 and a high-ablation rate laser ablation system provided significantly better sensitivity, detection limits, and accuracy compared to a conventional laser ablation system coupled with a quadrupole ICP-MS. The sensitivity ranges from about 590 cps for (35)Cl+ to more than 6 x 10(5) cps for (238)U+ for 1 microg of trace element per gram of coal sample. Detection limits vary from 450 ng g(-1) for chlorine and 18 ng g(-1) for sulfur to 9.5 pg g(-1) for mercury and 0.3 pg g(-1) for uranium. Analyses of minor and trace elements in four certified reference materials (BCR-180 Gas Coal, BCR-331 Steam Coal, SRM 1632c Trace Elements in Coal, SRM 1635 Trace Elements in Coal) yielded good agreement of usually not more than 5% deviation from the certified values and precisions of less than 10% relative standard deviation for most elements. Higher relative standard deviations were found for particular elements such as Hg and Cd caused by inhomogeneities due to associations of these elements within micro-inclusions in coal which was demonstrated for Hg in SRM 1635, SRM 1632c, and another standard reference material (SRM 2682b, Sulfur and Mercury in Coal). The developed LA-ICP-IDMS method with its simple sample pretreatment opens the possibility for accurate, fast, and highly sensitive determinations of environmentally critical contaminants in coal as well as of trace impurities in similar sample materials like graphite powder and activated charcoal on a routine basis.
NASA Astrophysics Data System (ADS)
Saha, Debasree; Chatterjee, Debashis; Chakravarty, Sanchita; Mazumder, Madhurina
2018-04-01
Coal samples of Samaleswari open cast coal block (S-OCB) are high ash (Aad, mean value 35.43%) and low sulphur content (St, on dry basis, mean value 0.91% < 1%) in quality. The stratigraphic variation of volatile matter and fixed carbon (dry ash-free) reflect a progress of coal metamorphism with depth that accordance to the coal rank variation from lignite to high volatile bituminous in the studied borehole. The younger coal seams have greater detrital minerals (quartz, illite, rutile) influence whereas older coal seams have greater authigenic mineral (kaolinite, dolomite, siderite, apatite) contribution that are possibly due to subsidence and sediment transportation. In S-OCB coal trace elements affinities in-between mineral and organic fraction are identified with statistical hierarchical cluster analysis. The work is further supported by the use of chemical fractionation experiment that reveals the multi mode of occurrence of several environmentally concern and interested trace elements (Sb, As, Be, Cd, Cr, Co, Cu, Pb, Mn, Ni, Zn). Among the analysed trace elements Co, Mn and Zn have major silicate association along with significant carbonate/oxide/monosulfide association. Whereas As, Cd, Cu, Pb and Ni have dominant pyritic association with notable silicate and carbonate/oxide/monosulfide association. The rest three elements (Sb, Be, Cr) have principally organic association with minor silicate and carbonate/oxide/monosulfide association. The stratigraphic variation of organo-mineral matrix content and detrital-authigenic mineral ratio are primarily related to coal rank. Geochemical character of coal also reflects a light towards proper utilisation of S-OCB coal from technical and environmental view point.
Elemental and Mineralogical Analysis of Silt Fraction from Site U1420, IODP Expedition 341
NASA Astrophysics Data System (ADS)
Salinas, J. K.; Jaeger, J. M.; Penkrot, M. L.
2016-12-01
In southeastern Alaska, the Chugach-St. Elias Mountains - the world's highest coastal mountain range - exhibit extreme topography due to the collision and subduction of the Yakutat microplate beneath the North American plate. The St. Elias orogen is younger than 30 Ma, with mountain building having occurred during a period of enhanced glacial erosion when erosive ice streams delivered sediment into the Gulf of Alaska. Integrated Ocean Drilling Program Expedition 341 set out to investigate the relationship between mountain building and glacial dynamics in the Gulf of Alaska. Sediment cores from site U1420 were collected, within the Bering trough, just offshore of the Bering Glacier. Analysis of Bering Trough seismic profiles demonstrates an evolution from tectonically-controlled to depositionally-controlled continental margin strata formation (Worthington et al., 2010). The goal of this study is to investigate the provenance of the silt-sized fraction (15-63 μm) of U1420 sediments across this transition in seismic facies using mineralogy and elemental geochemical analyses. XRD mineralogical analysis shows consistent downhole mineralogy with minor variations in relative peak intensities. Elemental ICP-MS geochemical analysis reveal concentrations of both major and trace elements to be very well constrained, with all major (Al, Ca, Fe, Mg, and Ti) and trace elemental data (Ce, Cr, Ga, La, Rb, Sc, Sr, Th, and Y) only varying downhole by few percent/ppm. Both the consistent downhole mineralogy and elemental data suggest that the provenance of the silt-sized sediment deposited offshore has not changed since initial deposition (<0.7 Ma). Comparison with onshore bedrock geochemistry and surface samples from the modern Gulf of Alaska indicate that U1420 silt is similar in composition to modern regional sediment sources and is a mixture of the different bedrock lithologies within the modern Bering Glacier drainage.
NASA Astrophysics Data System (ADS)
Marguí, E.; Queralt, I.; García-Ruiz, E.; García-González, E.; Rello, L.; Resano, M.
2018-01-01
Home-based collection protocols for clinical specimens are actively pursued as a means of improving life quality of patients. In this sense, dried blood spots (DBS) are proposed as a non-invasive and even self-administered alternative to sampling whole venous blood. This contribution explores the potential of energy dispersive X-ray fluorescence spectrometry for the simultaneous and direct determination of some major (S, Cl, K, Na), minor (P, Fe) and trace (Ca, Cu, Zn) elements in blood, after its deposition onto clinical filter papers, thus giving rise to DBS. For quantification purposes the best strategy was to use matrix-matched blood samples of known analyte concentrations. The accuracy and precision of the method were evaluated by analysis of a blood reference material (Seronorm™ trace elements whole blood L3). Quantitative results were obtained for the determination of P, S, Cl, K and Fe, and limits of detection for these elements were adequate, taking into account their typical concentrations in real blood samples. Determination of Na, Ca, Cu and Zn was hampered by the occurrence of high sample support (Na, Ca) and instrumental blanks (Cu, Zn). Therefore, the quantitative determination of these elements at the levels expected in blood samples was not feasible. The methodology developed was applied to the analysis of several blood samples and the results obtained were compared with those reported by standard techniques. Overall, the performance of the method developed is promising and it could be used to determine the aforementioned elements in blood samples in a simple, fast and economic way. Furthermore, its non-destructive nature enables further analyses by means of complementary techniques to be carried out.
Detrital and oceanic dysoxia influence on OAE2 sediment geochemistry from Tarfaya, SW Morocco
NASA Astrophysics Data System (ADS)
Turgeon, S. C.; Kolonic, S.; Brumsack, H.-J.; Wagner, T.
2003-04-01
The Cretaceous "greenhouse" world's stratigraphic record is punctuated by several important organic-rich intervals representing quasi-global "Oceanic Anoxic Events" (OAEs). This study focuses on sediments from Tarfaya in SW Morocco deposited during the Cenomanian-Turonian Boundary Event (CTBE or OAE2 at 93.5 Ma). These sediments consist of distinctly laminated, carbonate-rich black shales alternating with lighter coloured structureless intervals and sporadic chert lenses. Sediments from three sites representing proximal to distal settings were studied. Samples were analysed for Ctot, Corg, Stot, as well as several major-, minor- and trace elements using XRF and ICP-MS. These sediments are characterised by high Corg, Stot, and CaCO3 contents and consist of a simple two component mixing system ("average shale"-CaCO3). Major element concentrations are low, except for Ca and P, owing in part to the carbonate dilution effect. Most elements plot along "average shale" lines. Elements such as Si, Ti, Fe, K, Rb, and Zr show positive relationships with Al2O3, pointing to homogeneous source area material. Several Al-normalised elements (As, Ba, Cr, Cu, Ni, Sr, U, V, Y, Zn), many of them redox-sensitive or sulphide-residing, are enriched in the sediments indicating an oxygen-depleted environment and potential availability of hydrogen sulfide in the water column at the time of deposition. High Zn concentrations suggest increased submarine volcanism and/or hydrothermal activity during this time interval. High Ba concentrations are possibly indicative of high regional paleoproductivity, which is further supported by the elevated P concentrations hinting at nutrient availability. Basinward trends in the geochemical distribution of some elements are apparent and probably reflect the decreasing influence of terrestrial sediments away from the shoreline.
Finkelman, Robert B.; Fiene, F.L.; Miller, R.N.; Simon, F.O.
1984-01-01
Approximately 20 kg of the Herrin (No. 6) coal was collected from a strip mine in St. Clair County, Ill. A 10-kg portion was ground to -60 mesh, homogenized, and riffled into 128 splits of 70-80 g each. Homogeneity of these splits was confirmed by moisture, ash, and sulfur analyses of six randomly selected splits. Results of these analyses were within the ASTM (American Society for Testing and Materials) guidelines for interlaboratory precision. Splits of the Herrin (No. 6) coal were then transmitted to more than 30 laboratories for analysis. Low-temperature plasma oxidation was used to isolate inorganic matter for quantitative chemical and mineralogical analysis. Despite a wide variation in ashing conditions, only minor variations in ash yields were obtained; these variations were attributed to differences in operating temperature and moisture content. Mineralogical analyses of low-temperature ash (LTA) concentrates prepared by five different laboratories indicated variations within the limits of analytical error. The mean values, in weight percent, for the major minerals are as follows: calcite, 9; quartz, 20; pyrite, 23; kaolinite, 14; and illite+mixed-layer clays, 31. Normative mineralogical calculations and Fourier transform infrared analysis (FTIR) yielded results similar to those obtained from X-ray diffraction (XRD). Choosing appropriate mineral standards was found to be critical for the proper use of analytical techniques such as XRD and FTIR. Good interlaboratory agreement was obtained for most major, minor, and trace elements despite differences in analytical procedures and in the type of sample analyzed (coal, high-temperature ash, or LTA). Discrepancies between analyses for zinc, strontium, manganese, and iron may be attributed to sampling inhomogeneity problems. Mossbauer spectroscopy showed that approximately 44 percent of the pyritic sulfur was lost through weathering in the first year after preparation of the interlaboratory sample. Szomolnokite and possibly coquimbite and jarosite were also identified. Scanning electron microscopy studies indicated ubiquitous pyrite framboids and, less commonly, euhedral crystals, skeletal grains, irregularly shaped particles, and vein fillings. Minor accessory minerals such as rare-earth phosphates and possibly silicates, zircon, barium sulfate, titanium oxide, and sphalerite were also found. The textural evidence indicates that the minerals in the banded material are detrital whereas the minerals occurring as vein and pore fillings are authigenic. Magnetic measurements indicate that coal crushed in a steel pulverizer is contaminated by small quantities of abrasion fragments from the crusher, which seriously affect the measured magnetic properties of the coal.
NASA Astrophysics Data System (ADS)
Abrar, M.; Iqbal, T.; Fahad, M.; Andleeb, M.; Farooq, Z.; Afsheen, S.
2018-05-01
In the present work, the laser-induced breakdown spectroscopy technique is applied to explore the concentration of toxic elements present in cosmetic materials. The elemental analysis of chromium (Cr), magnesium (Mg), cadmium (Cd) and lead (Pb) are selected as major elements and manganese (Mn), sodium (Na), potassium (P), sulfur (S), silicon (Si) and titanium (Ti) as minor elements in cosmetic products. In this technique, a plasma plume is generated by using an Nd:YAG Laser of 532 nm wavelength and spectral lines for the respective samples are observed. Four different samples of cosmetic products are selected, i.e. two samples for lipstick and two for eyeshadow. The observed spectral lines of all major and minor elements are used to calculate their concentration in all samples through the intensity ratio method. Among selected lipstick and eyeshadow samples, one sample is branded, and one is collected from the local market. It is observed that chromium, magnesium and lead have strong spectral lines and consequently show high concentration. The calculated concentrations are then compared to permissible limits set by the Food and Drug Administration with regard to the cosmetics industry. The concentration of these toxic elements in selected local cosmetic samples exceeds the safe permissible limit for human use and could lead to serious health problems.
A Human Capital Approach to Reduce Health Disparities
Glover, Saundra H.; Xirasagar, Sudha; Jeon, Yunho; Elder, Keith T.; Piper, Crystal N.; Pastides, Harris
2010-01-01
Objective To introduce a human capital approach to reduce health disparities in South Carolina by increasing the number and quality of trained minority professionals in public health practice and research. Methods The conceptual basis and elements of Project EXPORT in South Carolina are described. Project EXPORT is a community based participatory research (CBPR) translational project designed to build human capital in public health practice and research. This project involves Claflin University (CU), a Historically Black College University (HBCU) and the African American community of Orangeburg, South Carolina to reduce health disparities, utilizing resources from the University of South Carolina (USC), a level 1 research institution to build expertise at a minority serving institution. The elements of Project EXPORT were created to advance the science base of disparities reduction, increase trained minority researchers, and engage the African American community at all stages of research. Conclusion Building upon past collaborations between HBCU’s in South Carolina and USC, this project holds promise for a public health human capital approach to reduce health disparities. PMID:21814634
NASA Astrophysics Data System (ADS)
Seal, R. R., II; Piatak, N. M.
2017-12-01
Carbonatites and alkaline intrusions are important sources of REEs. Environmental risks related to these deposit types have been assessed through literature review and evaluation of the geochemical properties of representative samples of mill tailings and their leachates. The main ore mineral in carbonatite deposits is bastnasite [(Ce,La)(CO3)F], which is found with dolomite and calcite ( 65 %), barite (20 - 25 %), plus a number of minor accessory minerals including sulfides such as galena and pyrite. Generally, alkaline intrusion-related REE deposits either occur in layered complexes or with dikes and veins cutting alkaline intrusions. Such intrusions have a more diverse group of REE ore minerals that include fluorcarbonates, oxides, silicates, and phosphates. Ore also can include minor calcite and iron (Fe), lead (Pb), and zinc (Zn) sulfides. The acid-generating potential of both deposit types is low because of a predominance of carbonate minerals in the carbonatite deposits, the presence of feldspars and minor calcite in alkaline intrusion-related deposits, and to only minor to trace occurrence of potentially acid-generating sulfide minerals. Both deposit types, however, are produced by igneous and hydrothermal processes that enrich high-field strength, incompatible elements, which typically are excluded from common rock-forming minerals. Elements such as yttrium (Y), niobium Nb), zirconium (Zr), hafnium (Hf), tungsten (W), titanium (Ti), tantalum (Ta), scandium (Sc), thorium (Th), and uranium (U) can be characteristic of these deposits and may be of environmental concern. Most of these elements, including the REEs, but with the exception of U, have low solubilities in water at the near-neutral pH values expected around these deposits. Mill tailings from carbonatite deposits can exceed residential soil and sediment criteria for Pb, and leachates from mill tailings can exceed drinking water guidelines for Pb. The greatest environmental challenges, however, are linked to the presence of Th and U, although mineral hosts for these elements are moderately unreactive in the environment. Both deposit types can have mill tailings that exceed residential soil criteria for U. Uranium can be recovered as a byproduct to mitigate its environmental effects, but Th remains a waste product that requires management.
Minor and trace element concentrations in adjacent kamacite and taenite in the Krymka chondrite
NASA Astrophysics Data System (ADS)
Meftah, N.; Mostefaoui, S.; Jambon, A.; Guedda, E. H.; Pont, S.
2016-04-01
We report in situ NanoSIMS siderophile minor and trace element abundances in individual Fe-Ni metal grains in the unequilibrated chondrite Krymka (LL3.2). Associated kamacite and taenite of 10 metal grains in four chondrules and one matrix metal were analyzed for elemental concentrations of Fe, Ni, Co, Cu, Rh, Ir, and Pt. The results show large elemental variations among the metal grains. However, complementary and correlative variations exist between adjacent kamacite-taenite. This is consistent with the unequilibrated character of the chondrite and corroborates an attainment of chemical equilibrium between the metal phases. The calculated equilibrium temperature is 446 ± 9 °C. This is concordant with the range given by Kimura et al. (2008) for the Krymka postaccretion thermal metamorphism. Based on Ni diffusivity in taenite, a slow cooling rate is estimated of the Krymka parent body that does not exceed ~1K Myr-1, which is consistent with cooling rates inferred by other workers for unequilibrated ordinary chondrites. Elemental ionic radii might have played a role in controlling elemental partitioning between kamacite and taenite. The bulk compositions of the Krymka metal grains have nonsolar (mostly subsolar) element/Ni ratios suggesting the Fe-Ni grains could have formed from distinct precursors of nonsolar compositions or had their compositions modified subsequent to chondrule formation events.
NASA Astrophysics Data System (ADS)
Van de Voorde, Lien; Vandevijvere, Melissa; Vekemans, Bart; Van Pevenage, Jolien; Caen, Joost; Vandenabeele, Peter; Van Espen, Piet; Vincze, Laszlo
2014-12-01
The most unique and only known 16th century Antwerp majolica tile floor in Belgium is situated in a tower of the Rameyenhof castle (Gestel, Belgium). This exceptional work of art has recently been investigated in situ by using X-ray fluorescence (XRF) and Raman spectroscopy in order to study the material characteristics. This study reports on the result of the analyses based on the novel combination of non-destructive and portable instrumentation, including a handheld XRF spectrometer for obtaining elemental information and a mobile Raman spectrometer for retrieving structural and molecular information on the floor tiles in the Rameyenhof castle and on a second, similar medallion, which is stored in the Rubens House museum in Antwerp (Belgium). The investigated material, majolica, is a type of ceramic, which fascinated many people and potters throughout history by its beauty and colourful appearance. In this study the characteristic major/minor and trace element signature of 16th century Antwerp majolica is determined and the pigments used for the colourful paintings present on the floor are identified. Furthermore, based on the elemental fingerprint of the white glaze, and in particular on the presence of zinc in the tiles - an element that was not used for making 16th century majolica - valuable information about the originality of the chapel floor and the two central medallions is acquired.
Inert matrix fuel neutronic, thermal-hydraulic, and transient behavior in a light water reactor
NASA Astrophysics Data System (ADS)
Carmack, W. J.; Todosow, M.; Meyer, M. K.; Pasamehmetoglu, K. O.
2006-06-01
Currently, commercial power reactors in the United States operate on a once-through or open cycle, with the spent nuclear fuel eventually destined for long-term storage in a geologic repository. Since the fissile and transuranic (TRU) elements in the spent nuclear fuel present a proliferation risk, limit the repository capacity, and are the major contributors to the long-term toxicity and dose from the repository, methods and systems are needed to reduce the amount of TRU that will eventually require long-term storage. An option to achieve a reduction in the amount, and modify the isotopic composition of TRU requiring geological disposal is 'burning' the TRU in commercial light water reactors (LWRs) and/or fast reactors. Fuel forms under consideration for TRU destruction in light water reactors (LWRs) include mixed-oxide (MOX), advanced mixed-oxide, and inert matrix fuels. Fertile-free inert matrix fuel (IMF) has been proposed for use in many forms and studied by several researchers. IMF offers several advantages relative to MOX, principally it provides a means for reducing the TRU in the fuel cycle by burning the fissile isotopes and transmuting the minor actinides while producing no new TRU elements from fertile isotopes. This paper will present and discuss the results of a four-bundle, neutronic, thermal-hydraulic, and transient analyses of proposed inert matrix materials in comparison with the results of similar analyses for reference UOX fuel bundles. The results of this work are to be used for screening purposes to identify the general feasibility of utilizing specific inert matrix fuel compositions in existing and future light water reactors. Compositions identified as feasible using the results of these analyses still require further detailed neutronic, thermal-hydraulic, and transient analysis study coupled with rigorous experimental testing and qualification.
ERIC Educational Resources Information Center
Paul, Faith G.
2005-01-01
A key element in educational reform has been to increase mathematical proficiency. We look at how five urban high schools with virtually all low-income, minority, and immigrant students have arranged for students to take algebra I, and we examine the course enrollments and grades of these student in the core college prep courses. Both preparation…
ERIC Educational Resources Information Center
Kanu, Yatta
2006-01-01
As a consequence of the Civil Rights Movement and related social movements, the past 30 years have witnessed an unprecedented rise in higher education enrollments among ethnic minority groups, women, and low-income students, as well as increases in the financial aid available to these groups. However, certain ethnic minority populations, such as…
NASA Astrophysics Data System (ADS)
Bolívar, J. P.; Olías, M.; González-García, F.; García-Tenorio, R.
2008-08-01
The levels and distribution of natural radionuclides in groundwaters from the unconfined Almonte-Marismas aquifer, upon which Doñana National Park is located, have been analysed. Most sampled points were multiple piezometers trying to study the vertical distribution of the hydrogeochemical characteristics in the aquifer. Temperature, pH, electrical conductivity, dissolved oxygen and redox potential were determined in the field. A large number of parameters, physico-chemical properties, major and minor ions, trace elements and natural radionuclides (U-isotopes, Th-isotopes, Ra-isotopes and 210Po), were also analysed. In the southern zone, where aeolian sands crop out, water composition is of the sodium chloride type, and the lower U-isotopes concentrations have been obtained. As water circulates through the aquifer, bicarbonate and calcium concentrations increase slightly, and higher radionuclides concentrations were measured. Finally, we have demonstrated that 234U/238U activity ratios can be used as markers of the type of groundwater and bedrock, as it has been the case for old waters with marine origin confined by a marsh in the south-east part of aquifer.
[Resilient or Risk Group? Psychological Burden at Unaccompanied Refugee Minors (URM) in Germany].
Rücker, Stefan; Büttner, Peter; Lambertz, Birgit; Karpinski, Norbert; Petermann, Franz
2017-04-01
Resilient or Risk Group? Psychological Burden at Unaccompanied Refugee Minors (URM) in Germany Unaccompanied minors (umA in German) are considered as a risk group for psychological disorders. In international studies a high prevalence for trauma, anxiety, and depression were reported. A sample of N = 52 unaccompanied minors living in Germany was questioned on symptom severity as well as stress experience with the Refugee Health Screening-15. More than each second unaccompanied minor shows clinically relevant symptom severity and stress experience. In age-specific analyses the highest stress levels were found among the youngest unaccompanied minors. Therefore, specifically adapted settings for care should be applied for this high-risk group.
Stewart, Jared J; Polutchko, Stephanie K; Demmig-Adams, Barbara; Adams, William W
2018-01-01
An Arabidopsis thaliana accession with naturally low vein density, Eifel-5 (Ei-5), was compared to Columbia-0 (Col-0) with respect to rosette growth, foliar vein architecture, photosynthesis, and transpiration. In addition to having to a lower vein density, Ei-5 grew more slowly, with significantly lower rates of rosette expansion, but had similar capacities for photosynthetic oxygen evolution on a leaf area basis compared to Col-0. The individual foliar minor veins were larger in Ei-5, with a greater number of vascular cells per vein, compared to Col-0. This compensation for low vein density resulted in similar values for the product of vein density × phloem cell number per minor vein in Ei-5 and Col-0, which suggests a similar capacity for foliar sugar export to support similar photosynthetic capacities per unit leaf area. In contrast, the product of vein density × xylem cell number per minor vein was significantly greater in Ei-5 compared to Col-0, and was associated not only with a higher ratio of water-transporting tracheary elements versus sugar-transporting sieve elements but also significantly higher foliar transpiration rates per leaf area in Ei-5. In contrast, previous studies in other systems had reported higher ratios of tracheary to sieve elements and higher transpiration rate to be associated with higher - rather than lower - vein densities. The Ei-5 accession thus further underscores the plasticity of the foliar vasculature by illustrating an example where a higher ratio of tracheary to sieve elements is associated with a lower vein density. Establishment of the Ei-5 accession, with a low vein density but an apparent overcapacity for water flux through the foliar xylem network, may have been facilitated by a higher level of precipitation in its habitat of origin compared to that of the Col-0 accession.
NASA Astrophysics Data System (ADS)
Deutsch, A.; Langenhorst, F.; Berndt, J.
2015-09-01
We report for the four internally rather homogeneous groups of glass (IVC, IVC-MT, BOT 12 [suevite], FBG) concentrations of major and 42 minor elements (in-situ data with LA-ICP-MS) as well as Sr-Nd, and DEGAS data.
Schibille, Nadine
2011-01-01
The chemical characterisation of archaeological glass allows the discrimination between different glass groups and the identification of raw materials and technological traditions of their production. Several lines of evidence point towards the large-scale production of first millennium CE glass in a limited number of glass making factories from a mixture of Egyptian mineral soda and a locally available silica source. Fundamental changes in the manufacturing processes occurred from the eight/ninth century CE onwards, when Egyptian mineral soda was gradually replaced by soda-rich plant ash in Egypt as well as the Islamic Middle East. In order to elucidate the supply and consumption of glass during this transitional period, 31 glass samples from the assemblage found at Pergamon (Turkey) that date to the fourth to fourteenth centuries CE were analysed by electron microprobe analysis (EPMA) and by laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS). The statistical evaluation of the data revealed that the Byzantine glasses from Pergamon represent at least three different glass production technologies, one of which had not previously been recognised in the glass making traditions of the Mediterranean. While the chemical characteristics of the late antique and early medieval fragments confirm the current model of glass production and distribution at the time, the elemental make-up of the majority of the eighth- to fourteenth-century glasses from Pergamon indicate the existence of a late Byzantine glass type that is characterised by high alumina levels. Judging from the trace element patterns and elevated boron and lithium concentrations, these glasses were produced with a mineral soda different to the Egyptian natron from the Wadi Natrun, suggesting a possible regional Byzantine primary glass production in Asia Minor. PMID:21526144
Jacobs, Aryana S.; Schwartz, Marc D.; Valdimarsdottir, Heiddis; Nusbaum, Rachel H.; Hooker, Gillian W.; DeMarco, Tiffani A.; Heinzmann, Jessica E.; McKinnon, Wendy; McCormick, Shelley R.; Davis, Claire; Forman, Andrea D.; Lebensohn, Alexandra Perez; Dalton, Emily; Tully, Diana Moglia; Graves, Kristi D.; Similuk, Morgan; Kelly, Scott; Peshkin, Beth N.
2016-01-01
Telephone genetic counseling (TC) for high-risk women interested in BRCA1/2 testing has been shown to yield positive outcomes comparable to usual care (UC; in-person) genetic counseling. However, little is known about how genetic counselors perceive the delivery of these alternate forms of genetic counseling. As part of a randomized trial of TC versus UC, genetic counselors completed a 5-item genetic counselor process questionnaire (GCQ) assessing key elements of pre-test sessions (information delivery, emotional support, addressing questions and concerns, tailoring of session, and facilitation of decision- making) with the 479 female participants (TC, N=236; UC, N=243). The GCQ scores did not differ for TC vs. UC sessions (t (477) = 0.11, p = 0.910). However, multivariate analysis showed that participant race/ethnicity significantly predicted genetic counselor perceptions (β = 0.172, p<0.001) in that the GCQ scores were lower for minorities in TC and UC. Exploratory analyses suggested that GCQ scores may be associated with patient preference for UC versus TC (t (79) = 2.21, p=0.030). Additionally, we found that genetic counselor ratings of session effectiveness were generally concordant with patient perceptions of the session. These data indicate that genetic counselors perceive that key components of TC can be delivered as effectively as UC, and that these elements may contribute to specific aspects of patient satisfaction. However, undefined process differences may be present which account for lower counselor perceptions about the effectiveness of their sessions with minority women (i.e., those other than non-Hispanic Whites). We discuss other potential clinical and research implications of our findings. PMID:26969308
Schibille, Nadine
2011-04-19
The chemical characterisation of archaeological glass allows the discrimination between different glass groups and the identification of raw materials and technological traditions of their production. Several lines of evidence point towards the large-scale production of first millennium CE glass in a limited number of glass making factories from a mixture of Egyptian mineral soda and a locally available silica source. Fundamental changes in the manufacturing processes occurred from the eight/ninth century CE onwards, when Egyptian mineral soda was gradually replaced by soda-rich plant ash in Egypt as well as the Islamic Middle East. In order to elucidate the supply and consumption of glass during this transitional period, 31 glass samples from the assemblage found at Pergamon (Turkey) that date to the fourth to fourteenth centuries CE were analysed by electron microprobe analysis (EPMA) and by laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS). The statistical evaluation of the data revealed that the Byzantine glasses from Pergamon represent at least three different glass production technologies, one of which had not previously been recognised in the glass making traditions of the Mediterranean. While the chemical characteristics of the late antique and early medieval fragments confirm the current model of glass production and distribution at the time, the elemental make-up of the majority of the eighth- to fourteenth-century glasses from Pergamon indicate the existence of a late Byzantine glass type that is characterised by high alumina levels. Judging from the trace element patterns and elevated boron and lithium concentrations, these glasses were produced with a mineral soda different to the Egyptian natron from the Wadi Natrun, suggesting a possible regional Byzantine primary glass production in Asia Minor.
NASA Astrophysics Data System (ADS)
Lee, Yonghoon; Nam, Sang-Ho; Ham, Kyung-Sik; Gonzalez, Jhanis; Oropeza, Dayana; Quarles, Derrick; Yoo, Jonghyun; Russo, Richard E.
2016-04-01
Laser-Induced Breakdown Spectroscopy (LIBS) and Laser-Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS), both based on laser ablation sampling, can be employed simultaneously to obtain different chemical fingerprints from a sample. We demonstrated that this analysis approach can provide complementary information for improved classification of edible salts. LIBS could detect several of the minor metallic elements along with Na and Cl, while LA-ICP-MS spectra were used to measure non-metallic and trace heavy metal elements. Principal component analysis using LIBS and LA-ICP-MS spectra showed that their major spectral variations classified the sample salts in different ways. Three classification models were developed by using partial least squares-discriminant analysis based on the LIBS, LA-ICP-MS, and their fused data. From the cross-validation performances and confusion matrices of these models, the minor metallic elements (Mg, Ca, and K) detected by LIBS and the non-metallic (I) and trace heavy metal (Ba, W, and Pb) elements detected by LA-ICP-MS provided complementary chemical information to distinguish particular salt samples.
NASA Astrophysics Data System (ADS)
Al-Bashaireh, Khaled
2018-02-01
This study aims at the identification of the provenance of white marble sculptures and architectural elements uncovered from the archaeological site of Gerasa and neighboring areas, north Jordan. Most of the marbles are probably of the Roman or Byzantine periods. Optical microscopy, X-ray diffraction, and mass spectrometry were used to investigate petrographic, mineralogical and isotopic characteristics of the samples, respectively. Analytical results were compared with the main reference databases of known Mediterranean marble quarries exploited in antiquity. The collected data show that the most likely main sources of the sculptures were the Greek marble quarries of Paros-2 (Lakkoi), Penteli (Mount Pentelikon, Attica), and Thasos-3 (Thasos Island, Cape Vathy, Aliki); the Asia Minor marble quarries of Proconessus-1 (Marmara) and Aphrodisias (Aphrodisias); and the Italian quarry of Carrara (Apuan Alps). Similarly, the Asia Minor quarries of the fine-grained Docimium (Afyon) and the coarse-grained Proconessus-1 (Marmara) and Thasos-3 are the most likely sources of the architectural elements. The results agree with published data on the wide use of these marbles for sculpture and architectural elements.
Verplanck, Philip L.; Van Gosen, Bradley S.; Seal, Robert R.; McCafferty, Anne E.
2014-01-01
The greatest environmental challenges associated with carbonatite and peralkaline intrusion-related rare earth element deposits center on the associated uranium and thorium. Considerable uncertainty exists around the toxicity of rare earth elements and warrants further investigation. The acid-generating potential of carbonatites and peralkaline intrusion-related deposits is low due to the dominance of carbonate minerals in carbonatite deposits, the presence of feldspars and minor calcite within the alkaline intrusion deposits, and only minor quantities of potentially acid-generating sulfides. Therefore, acid-drainage issues are not likely to be a major concern associated with these deposits. Uranium has the potential to be recovered as a byproduct, which would mitigate some of its environmental effects. However, thorium will likely remain a waste-stream product that will require management since progress is not being made towards the development of thorium-based nuclear reactors in the United States or other large scale commercial uses. Because some deposits are rich in fluorine and beryllium, these elements may be of environmental concern in certain locations.
The fate of minor alkali elements in the chemical evolution of salt lakes
2011-01-01
Alkaline earth elements and alkali metals (Mg, Ca, Na and K) play an important role in the geochemical evolution of saline lakes as the final brine type is defined by the abundance of these elements. The role of major ions in brine evolution has been studied in great detail, but little has been done to investigate the behaviour of minor alkali elements in these systems despite their similar chemical affinities to the major cations. We have examined three major anionic brine types, chloride, sulphate, and bicarbonate-carbonate, in fifteen lakes in North America and Antarctica to determine the geochemical behaviour of lithium, rubidium, strontium, and barium. Lithium and rubidium are largely conservative in all water types, and their concentrations are the result of long-term solute input and concentration through evaporation and/or sublimation. Strontium and barium behaviours vary with anionic brine type. Strontium can be removed in sulphate and carbonate-rich lakes by the precipitation of carbonate minerals. Barium may be removed in chloride and sulphate brines by either the precipitation of barite and perhaps biological uptake. PMID:21992434
Kuo, Fu Wen; Yang, Shu Ching
2017-12-01
This study aimed to elucidate whether the interaction of classroom composition and the need to belong influences belongingness seeking and, if so, to investigate how upward comparison mediates the effects. The analyses were conducted with a cross-sectional sample of 383 Taiwanese aboriginal adolescents (39.7% male) recruited from schools with mixed-sex/ethnicity (n = 113), single-sex (n = 122), and minority-only (n = 148) classrooms. After controlling for socioeconomic status, the moderation analyses indicated that participants with a chronic need to belong in classes with diversity (mixed sex/ethnicity) perceived higher social acceptance, while those with a chronic need to belong in homogeneous classes (single-sex and minority-only) reported greater feelings of rejection. Upward comparison for differentiation was found to influence the indirect effects of the need to belong on feelings of rejection and depression in single-sex and minority-only classes. In particular, the mediating effect of upward comparison was stronger in minority-only classes. Copyright © 2017 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.
Stricker, Gary D.; Flores, Romeo M.; Trippi, Michael H.; Ellis, Margaret S.; Olson, Carol M.; Sullivan, Jonah E.; Takahashi, Kenneth I.
2007-01-01
The U.S. Geological Survey (USGS), in cooperation with the Wyoming Reservoir Management Group (RMG) of the Bureau of Land Management (BLM) and nineteen independent coalbed methane (CBM) gas operators in the Powder River and Green River Basins in Wyoming and the Williston Basin in North Dakota, collected 963 coal samples from 37 core holes (fig. 1; table 1) between 1999 and 2005. The drilling and coring program was in response to the rapid development of CBM, particularly in the Powder River Basin (PRB), and the needs of the RMG BLM for new and more reliable data for CBM resource estimates and reservoir characterization. The USGS and BLM entered into agreements with the gas operators to drill and core Fort Union coal beds, thus supplying core samples for the USGS to analyze and provide the RMG with rapid, real-time results of total gas desorbed, coal quality, and high pressure methane adsorption isotherm data (Stricker and others, 2006). The USGS determined the ultimate composition of all coal core samples; for selected samples analyses also included proximate analysis, calorific value, equilibrium moisture, apparent specific gravity, and forms of sulfur. Analytical procedures followed those of the American Society of Testing Materials (ASTM; 1998). In addition, samples from three wells (129 samples) were analyzed for major, minor, and trace element contents. Ultimate and proximate compositions, calorific value, and forms of sulfur are fundamental parameters in evaluating the economic value of a coal. Determining trace element concentrations, along with total sulfur and ash yield, is also essential to assess the environmental effects of coal use, as is the suitability of the coal for cleaning, gasification, liquefaction, and other treatments. Determination of coal quality in the deeper part (depths greater than 1,000 to 1,200 ft) of the PRB (Rohrbacher and others, 2006; Luppens and others, 2006) is especially important, because these coals are targeted for future mining and development. This report contains summary tables, histograms, and isopleth maps of coal analyses. Details of the compositional internal variability of the coal beds are based on the continuous vertical sampling of coal sequences, including beds in the deeper part of the PRB. Such sampling allows for close comparisons of the compositions of different parts of coal beds as well as within the same coal beds at different core hole locations within short distances of each other.
NASA Astrophysics Data System (ADS)
Wohlgemuth-Ueberwasser, Cora C.; Viljoen, Fanus; Petersen, Sven; Vorster, Clarisa
2015-06-01
The key for understanding the trace metal inventory of currently explored VHMS deposits lies in the understanding of trace element distribution during the formation of these deposits on the seafloor. Recrystallization processes already occurring at the seafloor might liberate trace elements to later hydrothermal alteration and removement. To investigate the distribution and redistribution of trace elements we analyzed sulfide minerals from 27 black smoker samples derived from three different seafloor hydrothermal fields: the ultramafic-hosted Logatchev hydrothermal field on the Mid-Atlantic Ridge, the basaltic-hosted Turtle Pits field on the mid-atlantic ridge, and the felsic-hosted PACMANUS field in the Manus basin (Papua New Guinea). The sulfide samples were analyzed by mineral liberation analyser for the modal abundances of sulfide minerals, by electron microprobe for major elements and by laser ablation-inductively coupled plasma-mass spectrometry for As, Sb, Se, Te, and Au. The samples consist predominantly of chalcopyrite, sphalerite, pyrite, galena and minor isocubanite as well as inclusions of tetrahedrite-tennantite. Laser ablation spectra were used to evaluate the solubility limits of trace elements in different sulfide minerals at different textures. The solubility of As, Sb, and Au in pyrite decreases with increasing degree of recrystallization. When solubility limits are reached these elements occur as inclusions in the different sulfide phases or they are expelled from the mineral phase. Most ancient VHMS deposits represent felsic or bimodal felsic compositions. Samples from the felsic-hosted PACMANUS hydrothermal field at the Pual ridge (Papua New Guinea) show high concentrations of Pb, As, Sb, Bi, Hg, and Te, which is likely the result of an additional trace element contribution derived from magmatic volatiles. Co-precipitating pyrite and chalcopyrite are characterized by equal contents of Te, while chalcopyrite that replaced pyrite (presumably during black smoker growth) is enriched in Te relative to pyrite. These higher Te concentrations may be related to higher fluid temperature.
The hoard of Beçin—non-destructive analysis of the silver coins
NASA Astrophysics Data System (ADS)
Rodrigues, M.; Schreiner, M.; Mäder, M.; Melcher, M.; Guerra, M.; Salomon, J.; Radtke, M.; Alram, M.; Schindel, N.
2010-05-01
We report the results of an analytical investigation on 416 silver-copper coins stemming from the Ottoman Empire (end of 16th and beginning of 17th centuries), using synchrotron micro X-ray fluorescence analysis (SRXRF). In the past, analyses had already been conducted with energy dispersive X-ray fluorescence analysis (EDXRF), scanning electron microscopy with energy dispersive X-ray spectrometry (SEM/EDX) and proton induced X-ray emission spectroscopy (PIXE). With this combination of techniques it was possible to confirm the fineness of the coinage as well as to study the provenance of the alloy used for the coins. For the interpretation of the data statistical analysis (principal component analysis—PCA) has been performed. A definite local assignment was explored and significant clustering was obtained regarding the minor and trace elements composing the coin alloys.
Hooker, Claire; Chapman, Simon
2006-02-01
To analyse structural factors revealed by politicians that shaped legislation on tobacco control in New South Wales, 1955-95. Parliamentary debates and other records were collected. Open-ended interviews were conducted with 17 Members of Parliament (MPs) who were significantly involved, and then analysed for structural elements. Tobacco industry lobbying had a significant but limited influence on policy making, being exerted largely through social interactions with executives and based on concerns about the economic impact on third parties. MPs saw health advocates' chief functions as (1) generating community concern about the issue and support for control measures, and (2) bringing any new information to political attention, providing pro-control arguments and data through the media. Factors that delayed tobacco control policies included: the conservative stance of Premiers and major parties, commitments to unanimous federal action, and rivalry between parties. Factors that facilitated control policies included: reforms that gave the Legislative Council increased power, the use of parliamentary committees, and backbencher and grass roots support. Tobacco control policy and legislation has been the product of political structures that gave power to those MPs in the least powerful positions--minor parties, Members of the Legislative Council (MLCs), backbenchers, women and party rank and file--rather than to major parties and their executives. Advocates should make the most of their access points to the political process, providing information, arguments and support and demonstrating public opinion in favour of further control.
NASA Astrophysics Data System (ADS)
Re, Alessandro; Angelici, Debora; Lo Giudice, Alessandro; Corsi, Jacopo; Allegretti, Silvia; Biondi, Alessia Fabiola; Gariani, Gianluca; Calusi, Silvia; Gelli, Nicla; Giuntini, Lorenzo; Massi, Mirko; Taccetti, Francesco; La Torre, Leonardo; Rigato, Valentino; Pratesi, Giovanni
2015-04-01
The first part of this study reports on the wide campaign for the extension of the database of both trace and minor elements concentration in diopside by means of μ-PIXE measurements and of luminescence spectra in diopside and wollastonite by means of μ-IL measurements. Diopside and wollastonite are actually two of the most common lapis lazuli-forming minerals. For this former part of the study, we analysed rocks of known provenance at the microbeam line of the LNL laboratories in Legnaro (PD) of the Istituto Nazionale di Fisica Nucleare (INFN). The latter part of the paper is dedicated to the non-invasive Ion Beam Analyses (IBA) characterisation of six pieces of the "Collezione Medicea". The collection is exhibited at the Museum of Natural History (University of Firenze) and belonged to the Medici family. It includes artworks made of lapis lazuli manufactured in the 16th and 17th centuries but there is not precise information about the provenance of the used raw material. Results on the artworks show, as expected, that the Chilean provenance of the material used for the analysed artworks has to be excluded. Lapis lazuli used for five of the analysed artworks can be ascribed to the Afghan quarry district, while one object cannot be attributed only on the base of diopside and wollastonite analysis.
Geochemistry and economic potential of massive sulfide deposits from the eastern Pacific Ocean
Bischoff, James L.; Rosenbauer, R.J.; Aruscavage, P. J.; Baedecker, P.A.; Crock, J.G.
1983-01-01
Bulk chemical analyses are performed for major and minor elements using a variety of techniques on a suite of 9 samples of sea floor massive sulfide deposits from 21?N EPR, Juan de Fuca Ridge and Galapagos Rift. Results indicate that deposits at 21?N and Juan de Fuca are very similar despite a geographic separation of 2300 km and are composed primarily of Zn, Fe, and S, with important minor concentrations of Ag, As, Cd and Ge. The Galapagos Rift massive sulfide is primarily Fe, Cu and S and with important minor contents of only Co and Mo. Au is low, ranging from below detection up to 0.17 ppm. Pt group metals are very low, and average about 0.001 ppm. Consideration of enrichment factors and relative metal abundance suggests that MORB is a sufficient source for all the metals enriched in the sea floor deposits. The economically important metals for the 21?N and Juan de Fuca deposits are primarily Zn and Ag, (97%) with potential by-products of Cu, Cd and possibly, Ge. For the Galapagos Rift, the primary value is with Cu (86%) with potential by-products of Co and Mo. The Galapagos Rift deposit is similar to, but contains about twice the Cu content, of typical ore from the Skouriotisa mine of the Troodos complex of Cyprus. The grade of the 21?N/Juan de Fuca deposits is 4 times greater than that of the Galapagos Rift and about twice that of prime deep-sea manganese nodules.
In situ semi-quantitative analysis of polluted soils by laser-induced breakdown spectroscopy (LIBS).
Ismaël, Amina; Bousquet, Bruno; Michel-Le Pierrès, Karine; Travaillé, Grégoire; Canioni, Lionel; Roy, Stéphane
2011-05-01
Time-saving, low-cost analyses of soil contamination are required to ensure fast and efficient pollution removal and remedial operations. In this work, laser-induced breakdown spectroscopy (LIBS) has been successfully applied to in situ analyses of polluted soils, providing direct semi-quantitative information about the extent of pollution. A field campaign has been carried out in Brittany (France) on a site presenting high levels of heavy metal concentrations. Results on iron as a major component as well as on lead and copper as minor components are reported. Soil samples were dried and prepared as pressed pellets to minimize the effects of moisture and density on the results. LIBS analyses were performed with a Nd:YAG laser operating at 1064 nm, 60 mJ per 10 ns pulse, at a repetition rate of 10 Hz with a diameter of 500 μm on the sample surface. Good correlations were obtained between the LIBS signals and the values of concentrations deduced from inductively coupled plasma atomic emission spectroscopy (ICP-AES). This result proves that LIBS is an efficient method for optimizing sampling operations. Indeed, "LIBS maps" were established directly on-site, providing valuable assistance in optimizing the selection of the most relevant samples for future expensive and time-consuming laboratory analysis and avoiding useless analyses of very similar samples. Finally, it is emphasized that in situ LIBS is not described here as an alternative quantitative analytical method to the usual laboratory measurements but simply as an efficient time-saving tool to optimize sampling operations and to drastically reduce the number of soil samples to be analyzed, thus reducing costs. The detection limits of 200 ppm for lead and 80 ppm for copper reported here are compatible with the thresholds of toxicity; thus, this in situ LIBS campaign was fully validated for these two elements. Consequently, further experiments are planned to extend this study to other chemical elements and other matrices of soils.
Tourtelot, Harry Allison; Tailleur, Irvin L.
1971-01-01
The Shublik Formation (Middle and Late Triassic) is widespread in the surface and subsurface of northern Alaska. Four stratigraphic sections along about 70 miles of the front of the northeastern Brooks Range east of the Canning giver were examined and sampled in detail in 1968. These sections and six-step spectrographic and carbon analyses of the samples combined with other data to provide a preliminary local description of the highly organic unit and of the paleoenvironments. Thicknesses measured between the overlying Kingak Shale of Jurassic age and the underlying Sadlerochit Formation of Permian and Triassic age range from 400 to more than 800 feet but the 400 feet, obtained from the most completely exposed section, may be closer to the real thickness across the region. The sections consist of organic-rich, phosphatic, and fossiliferous muddy, silty, or carbonate rocks. The general sequence consists, from the bottom up, of a lower unit of phosphatic siltstone, a middle unit of phosphatic carbonate rocks, and an upper unit of shale and carbonate rocks near the Canning River and shale, carbonate rocks, and sandstone to the east. Although previously designated a basal member of the Kingak Shale (Jurassic), the upper unit is here included with the Shublik on the basis of its regional lithologic relation. The minor element compositions of the samples of the Shublik Formation are consistent with their carbonaceous and phosphatic natures in that relatively large amounts of copper, molybdenum, nickel, vanadium and rare earths are present. The predominantly sandy rocks of the underlying Sadlerochit Formation (Permian and Triassic) have low contents of most minor elements. The compositions of samples of Kingak Shale have a wide range not readily explicable by the nature of the rock: an efflorescent sulfate salt contains 1,500 ppm nickel and 1,500 ppm zinc and large amounts of other metals derived from weathering of pyrite and leaching of local shale. The only recorded occurrence of silver and 300 ppm lead in gouge along a shear plane may be the result of metals introduced from an extraneous source. The deposits reflect a marine environment that deepened somewhat following deposition of the Sadlerochit Formation and then shoaled during deposition of the upper limestone-siltstone unit. This apparently resulted from a moderate transgression and regression of the sea with respect to a northwest-trending line between Barrow and the Brooks Range at the International Boundary. Nearer shore facies appear eastward. The phosphate in nodules, fossil molds and oolites, appears to have formed diagenetically within the uncompacted sediment.
A Transparently-Scalable Metadata Service for the Ursa Minor Storage System
2010-06-25
provide application-level guarantees. For example, many document editing programs imple- ment atomic updates by writing the new document ver- sion into a...Transparently-Scalable Metadata Service for the Ursa Minor Storage System 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6...operations that could involve multiple servers, how close existing systems come to transparent scala - bility, how systems that handle multi-server
NASA Astrophysics Data System (ADS)
Li, Zhu-bai; Wang, Li-chen; Geng, Xiao-peng; Hu, Feng-xia; Sun, Ji-rong; Shen, Bao-gen
2017-03-01
Magnetic materials of MM-Fe-B (MM=mischmetal) ribbons were prepared using melt spinning method by varying the content of MM. The ribbons contain minor phases besides the main phase of Re2Fe14B. X-ray techniques show that the diffraction peak intensities of the minor phase Fe3B vary with the content of constituent elements, indicating that the amount of minor phase could be tunable. The squareness of hysteresis loop is the best in MM13Fe80.5B6.5 ribbons, which should mainly ascribe to the less amount of minor phase. Henkel plots verify the more uniform magnetization reversals in MM13Fe80.5B6.5 ribbons, and the energy product achieves to the maximum of 12.74 MGOe with the coercivity of 6.50 kOe. With the increase of MM content the coercivity increases monotonically, and reaches to 9.13 kOe in MM15Fe77.5B7.5 ribbons, which should be related with the nature of the defects in the main phase. These investigations show that optimizing the content of constituent elements and phase constitution could improve magnetic properties in the resource-saving magnets of MM-Fe-B ribbons.
Quantification of Methylated Selenium, Sulfur, and Arsenic in the Environment
Vriens, Bas; Ammann, Adrian A.; Hagendorfer, Harald; Lenz, Markus; Berg, Michael; Winkel, Lenny H. E.
2014-01-01
Biomethylation and volatilization of trace elements may contribute to their redistribution in the environment. However, quantification of volatile, methylated species in the environment is complicated by a lack of straightforward and field-deployable air sampling methods that preserve element speciation. This paper presents a robust and versatile gas trapping method for the simultaneous preconcentration of volatile selenium (Se), sulfur (S), and arsenic (As) species. Using HPLC-HR-ICP-MS and ESI-MS/MS analyses, we demonstrate that volatile Se and S species efficiently transform into specific non-volatile compounds during trapping, which enables the deduction of the original gaseous speciation. With minor adaptations, the presented HPLC-HR-ICP-MS method also allows for the quantification of 13 non-volatile methylated species and oxyanions of Se, S, and As in natural waters. Application of these methods in a peatland indicated that, at the selected sites, fluxes varied between 190–210 ng Se·m−2·d−1, 90–270 ng As·m−2·d−1, and 4–14 µg S·m−2·d−1, and contained at least 70% methylated Se and S species. In the surface water, methylated species were particularly abundant for As (>50% of total As). Our results indicate that methylation plays a significant role in the biogeochemical cycles of these elements. PMID:25047128
Integrated Experimental and Modelling Research for Non-Ferrous Smelting and Recycling Systems
NASA Astrophysics Data System (ADS)
Jak, Evgueni; Hidayat, Taufiq; Shishin, Denis; Mehrjardi, Ata Fallah; Chen, Jiang; Decterov, Sergei; Hayes, Peter
The chemistries of industrial pyrometallurgical non-ferrous smelting and recycling processes are becoming increasingly complex. Optimisation of process conditions, charge composition, temperature, oxygen partial pressure, and partitioning of minor elements between phases and different process streams require accurate description of phase equilibria and thermodynamics which are the focus of the present research. The experiments involve high temperature equilibration in controlled gas atmospheres, rapid quenching and direct measurement of equilibrium phase compositions with quantitative microanalytical techniques including electron probe X-ray microanalysis and Laser Ablation ICP-MS. The thermodynamic modelling is undertaken using computer package FactSage with the quasi-chemical model for the liquid slag phase and other advanced models. Experimental and modelling studies are combined into an integrated research program focused on the major elements Cu-Pb-Fe-O-Si-S system, slagging Al, Ca, Mg and other minor elements. The ongoing development of the research methodologies has resulted in significant advances in research capabilities. Examples of applications are given.
NASA Astrophysics Data System (ADS)
Krüger, Harald; Stephan, Thomas; Engrand, Cécile; Briois, Christelle; Siljeström, Sandra; Merouane, Sihane; Baklouti, Donia; Fischer, Henning; Fray, Nicolas; Hornung, Klaus; Lehto, Harry; Orthous-Daunay, Francois-Régis; Rynö, Jouni; Schulz, Rita; Silén, Johan; Thirkell, Laurent; Trieloff, Mario; Hilchenbach, Martin
2015-11-01
COmetary Secondary Ion Mass Analyzer (COSIMA) is a time-of-flight secondary ion mass spectrometry (TOF-SIMS) instrument on board the Rosetta space mission. COSIMA has been designed to measure the composition of cometary dust particles. It has a mass resolution m/Δm of 1400 at mass 100 u, thus enabling the discrimination of inorganic mass peaks from organic ones in the mass spectra. We have evaluated the identification capabilities of the reference model of COSIMA for inorganic compounds using a suite of terrestrial minerals that are relevant for cometary science. Ground calibration demonstrated that the performances of the flight model were similar to that of the reference model. The list of minerals used in this study was chosen based on the mineralogy of meteorites, interplanetary dust particles and Stardust samples. It contains anhydrous and hydrous ferromagnesian silicates, refractory silicates and oxides (present in meteoritic Ca-Al-rich inclusions), carbonates, and Fe-Ni sulfides. From the analyses of these minerals, we have calculated relative sensitivity factors for a suite of major and minor elements in order to provide a basis for element quantification for the possible identification of major mineral classes present in the cometary particles.
NASA Technical Reports Server (NTRS)
Arya, Vinod K.; Halford, Gary R.
1993-01-01
The feasibility of a viscoplastic model incorporating two back stresses and a drag strength is investigated for performing nonlinear finite element analyses of structural engineering problems. To demonstrate suitability for nonlinear structural analyses, the model is implemented into a finite element program and analyses for several uniaxial and multiaxial problems are performed. Good agreement is shown between the results obtained using the finite element implementation and those obtained experimentally. The advantages of using advanced viscoplastic models for performing nonlinear finite element analyses of structural components are indicated.
Mediating Factors Explaining the Association Between Sexual Minority Status and Dating Violence.
Martin-Storey, Alexa; Fromme, Kim
2017-08-01
Dating violence presents a serious threat for individual health and well-being. A growing body of literature suggests that starting in adolescence, individuals with sexual minority identities (e.g., individuals who identify as gay, lesbian, or bisexual) may be at an increased risk for dating violence compared with heterosexuals. Research has not, however, identified the mechanisms that explain this vulnerability. Using a diverse sample of young adults ( n = 2,474), the current study explored how minority stress theory, revictimization theory, sex of sexual partners, and risky sexual behavior explained differences in dating violence between sexual minority and heterosexual young adults. Initial analyses suggested higher rates of dating violence among individuals who identified as bisexual, and individuals who identified as gay or lesbian when compared with heterosexuals, and further found that these associations failed to differ across gender. When mediating and control variables were included in the analyses, however, the association between both sexual minority identities and higher levels of dating violence became nonsignificant. Of particular interest was the role of discrimination, which mediated the association between bisexual identity and dating violence. Other factors, including sex and number of sexual partners, alcohol use, and childhood maltreatment, were associated with higher rates of dating violence but did not significantly explain vulnerability among sexual minority individuals compared with their heterosexual peers. These findings suggest the importance of minority stress theory in explaining vulnerability to dating violence victimization among bisexuals in particular, and generally support the importance of sexual-minority specific variables in understanding risk for dating violence within this vulnerable population.
NASA Astrophysics Data System (ADS)
Abdullatif, Osman; Abdlmutalib, Ammar; Ahmed, Jarrah; Abdelgadir, Mohamed; Adam, Ammar
2017-04-01
The Permian-Triassic Khuff Formation carbonate reservoirs (and equivalents) in the Middle East are estimated to contain about 15-20 % of the world's gas reserves. Excellently exposed outcropping Khuff strata in central Saudi Arabia provide good outcrop equivalents to the Khuff Formation in the subsurface. The Khuff Formation is composed of five members and from bottom to top are Ash Shiqqah, Huqayl, Duhaysan, Midnab and Khartam members. The Carbonates lithofacies dominate with minor terrestrial clastics, and the paleoenvironments vary from terrestrial, sabkha, tidal-intertidal and open marine environments. This study investigates the relationship between lithostratigraphy, sequence stratigraphy and chemostratigraphy by integration of both field and laboratory sedimentological and chemical elements data. The vertical chemical elements profiles along the Khuff members show variations in their chemical elements content with the variation in lithofacies types, staking pattern, depositional and stratigraphic pattern. The chemostratigraphic distribution of the chemical elements also showed variation within and between the Khuff members. There is a general agreement between chemostratigraphic analyses based on vertical profiles and binary cross plots. The Khuff members and their stratigraphic boundaries can be differentiated based on their chemostratigraphic signatures. Moreover, the lithofacies and depositional paleoenvironmental of different Khuff members can be identified based on their chemical element contents. Chemostratigraphic zones or clusters are markedly established indicating different lithofacies and depositional paleoenvironments. Terrestrial, channel, lacustrine, shoreline to open marine carbonate lithofacies, as building blocks of sequence stratigraphy, all may be distinguished based on their chemical signatures. These outcrop analog results might be of significance to lithofacies, paleoenvironmental, stratigraphic identification, classification and correlation of Khuff Formation in the subsurface. The results might also provide guides and application to reservoir Khuff Formation identification, layering and zonation in the subsurface.
Comparison between PGAA and ID-AMS analysis for determining chlorine content in whole rock basalt
NASA Astrophysics Data System (ADS)
di Nicola, L.; Schnabel, C.; Wilcken, K. M.; Gméling, K.
2009-04-01
Accurate determination of chlorine concentrations in terrestrial rocks is of importance for the interpretation of terrestrial in-situ cosmogenic 36Cl. Neutron capture by 35Cl, together with production from Ca and K, is one of the three major production pathways of 36Cl in rocks. Here, we present an inter-comparison of chlorine determinations by two procedures. The first approach is an independent Cl determination by prompt gamma (neutron) activation analysis (PGAA). The second method is isotope dilution based on isotopically-enriched stable chlorine carrier added during chemical sample preparation for accelerator mass spectrometry (ID-AMS). Twenty six (26) whole rock samples have been processed for PGAA and ID-AMS analyses. Elemental analysis by PGAA provides concentrations of major, minor and trace elements including the target elements for 36Cl production (K, Ca, Ti, and Fe), as well as of neutron absorbers and neutron moderators (H, B, Cl, Sm and Gd). The Cl concentrations determined during this study constitute the first inter-comparison for concentrations below 100 μCl/g. Our results show no significant difference in Cl concentrations between methods, and comparable uncertainties. This agreement guarantees that during the procedure we employ for whole rock sample no significant loss of stable chlorine from either the spike or the sample occurs before isotopic equilibration, prior to AgCl precipitation. Furthermore, we show that the elemental analysis by PGAA offers anadvance for the interpretation of 36Cl measurements. It allows simultaneous measurement of major and most trace element concentrations with a precision necessary for calculating the relative contributions to 36Cl production rates of the different mechanisms. Finally, the Cl concentration can be used to optimize the amount of isotopically-enriched spike for AMS-ID sample preparation for 36Cl.
NASA Technical Reports Server (NTRS)
Wopenka, Brigitte; Jollife, Bradley L.; Zinner, Ernst; Kremser, Daniel T.
1996-01-01
We have determined major (Si, Zr, Hf), minor (Al, Y, Fe, P), and trace element (Ca, Sc, Ti, Ba, REE, Th, U) concentrations and Raman spectra of a zoned, 200 microns zircon grain in lunar sample 14161,7069, a quartz monzodiorite breccia collected at the Apollo 14 site. Analyses were obtained on a thin section in situ with an ion microprobe, an electron microprobe, and a laser Raman microprobe. The zircon grain is optically zoned in birefringence, a reflection of variable (incomplete) metamictization resulting from zo- nation in U and Th concentrations. Variations in the concentrations of U and Th correlate strongly with those of other high-field-strength trace elements and with changes in Raman spectral parameters. Concentrations of U and Th range from 21 to 55 ppm and 6 to 31 ppm, respectively, and correlate with lower Raman peak intensities, wider Raman peaks, and shifted Si-O peak positions. Concentrations of heavy rare earth elements range over a factor of three to four and correlate with intensities of fluorescence peaks. Correlated variations in trace element concentrations reflect the original magmatic differentiation of the parental melt approx. 4 b.y. ago. Degradation of the zircon structure, as reflected by the observed Raman spectral parameters, has occurred in this sample over a range of alpha-decay event dose from approx. 5.2 x 10(exp 14) to 1.4 x 10(exp 15) decay events per milligram of zircon, as calculated from the U and Th concentrations. This dose is well below the approx. 10(exp 16) events per milligram cumulative dose that causes complete metamictization and indicates that laser Raman microprobe spectroscopy is an analytical technique that is very sensitive to the radiation-induced damage in zircon.
NASA Astrophysics Data System (ADS)
Armstrong, J. T.; McSwiggen, P.; Nielsen, C.
2013-12-01
Quantitative electron microprobe analysis has revolutionized two-dimensional elemental analysis of Earth materials at the micrometer-scale. Newly available commercial field emission (FE-) source instruments represent significant technological advances in quantitative measurement with high spatial resolution at sub-micrometer scale - helping to bridge the gap between conventional microprobe and AEM analyses. Their performance specifications suggest the ability to extend routine quantitative analyses from ~3-5 micrometer diameter areas down to 1-2 micrometer diameter at beam energies of 15 keV; and, with care, down to 200-500 nm diameter at reduced beam energies. . In order to determine whether the level of performance suggested by the specifications is realistic, we spent a week doing analyses at the newly installed JEOL JXA-8530F field emission microprobe at Arizona State University, using a series of samples that are currently being studied in various projects at CIW. These samples included: 1) high-pressure experiment run product containing intergrowths of sub-micrometer grains of metal, sulfide, Fe-Mg-perovskite, and ferropericlase; 2) a thin section of the Ivankinsky basalt, part of the Siberian flood basalt sequence containing complex sub-micrometer intergrowths of magnetite, titanomagnetite, ilmenite, titanite and rutile; 3) a polished section of the Giroux pallasite, being studied for element partitioning, that we used as an analogue to test the capabilities for zonation and diffusion determination; and 4) a polished section of the Semarkona ordinary chondrite containing chondules comprised of highly zoned and rimmed olivines and pyroxenes in a complex mesostasis of sub-micrometer pyroxenes and glass. The results of these analyses that we will present confirmed our optimism regarding the new analytical capabilities of a field emission microprobe. We were able, at reduced voltages, to accurately analyze the major and minor element composition of intergrowth and rimming phases as small as 200 nm without artifact contribution from the surrounding phases. We were able to determine the compositional gradients at kamacite-taenite boundaries in the pallasite specimen with a resolution of ~180 nm, enabling much higher precision and accuracy determination of the meteorite's cooling rate than previously possible with microprobe measurements. We were able to determine the composition and zonation of phases in the experimental run product, none of which were large enough to be analyzable in a conventional electron microprobe.
Öner-Sieben, Soner; Rappl, Christine; Sauer, Norbert; Stadler, Ruth; Lohaus, Gertrud
2015-01-01
Trees are generally assumed to be symplastic phloem loaders. A typical feature for most wooden species is an open minor vein structure with symplastic connections between mesophyll cells and phloem cells, which allow sucrose to move cell-to-cell through the plasmodesmata into the phloem. Fraxinus excelsior (Oleaceae) also translocates raffinose family oligosaccharides in addition to sucrose. Sucrose concentration was recently shown to be higher in the phloem sap than in the mesophyll cells. This suggests the involvement of apoplastic steps and the activity of sucrose transporters in addition to symplastic phloem-loading processes. In this study, the sucrose transporter FeSUT1 from F. excelsior was analysed. Heterologous expression in baker’s yeast showed that FeSUT1 mediates the uptake of sucrose. Immunohistochemical analyses revealed that FeSUT1 was exclusively located in phloem cells of minor veins and in the transport phloem of F. excelsior. Further characterization identified these cells as sieve elements and possibly ordinary companion cells but not as intermediary cells. The localization and expression pattern point towards functions of FeSUT1 in phloem loading of sucrose as well as in sucrose retrieval. FeSUT1 is most likely responsible for the observed sucrose gradient between mesophyll and phloem. The elevated expression level of FeSUT1 indicated an increased apoplastic carbon export activity from the leaves during spring and late autumn. It is hypothesized that the importance of apoplastic loading is high under low-sucrose conditions and that the availability of two different phloem-loading mechanisms confers advantages for temperate woody species like F. excelsior. PMID:26022258
ERIC Educational Resources Information Center
Fox, Louis
2007-01-01
Advanced information, communication, computation and collaboration technologies, known as "cyberinfrastructure," have become essential elements for research, education, and innovation in the 21st century. A major challenge confronting the United States today is how to ensure that all colleges and universities, including those that have…
Alvarado, Sandra; Guédez, Magdiel; Lué-Merú, Marcó P; Nelson, Graterol; Alvaro, Anzalone; Jesús, Arroyo C; Gyula, Záray
2008-11-01
In this study the removal of arsenic by the Water Hyacinth (Eichhornia crassipes) and Lesser Duckweed (Lemna minor) was monitored under a concentration of 0.15mgL(-1) of the element. Plant densities were 1kg/m2 for Lesser Duckweed and 4kg/m2 for Water Hyacinth on a wet basis. The arsenic was determined in foliar tissue and water samples by hydride generation atomic absorption spectroscopy. The element was monitored as a function of time during 21 days. No significant differences were found in the bioaccumulation capability of both species. The removal rate for L. minor was 140mg As/had with a removal recovery of 5%. The Water Hyacinth had a removal rate of 600mg As/had and a removal recovery of 18%, under the conditions of the assay. The removal efficiency of Water Hyacinth was higher due to the biomass production and the more favorable climatic conditions. This specie represents a reliable alternative for arsenic bioremediation in waters.
Todorov, Todor I.; Wolf, Ruth E.; Adams, Monique
2014-01-01
Typically, 27 major, minor, and trace elements are determined in natural waters, acid mine drainage, extraction fluids, and leachates of geological and environmental samples by inductively coupled plasma-optical emission spectrometry (ICP-OES). At the discretion of the analyst, additional elements may be determined after suitable method modifications and performance data are established. Samples are preserved in 1–2 percent nitric acid (HNO3) at sample collection or as soon as possible after collection. The aqueous samples are aspirated into the ICP-OES discharge, where the elemental emission signals are measured simultaneously for 27 elements. Calibration is performed with a series of matrix-matched, multi-element solution standards.
Baldwin, Aleta; Dodge, Brian; Schick, Vanessa; Herbenick, Debra; Sanders, Stephanie A; Dhoot, Roshni; Fortenberry, J Dennis
2017-11-01
Disclosure of sexual identity among sexual minority women is related to better outcomes and improved quality of care. The existing literature on sexual minority women's experiences of identity disclosure and related interactions with healthcare providers draws little distinction between different groups of sexual minority women, despite the different barriers, stigma and health outcomes that exist between them. This paper presents factors influencing identity disclosure and describes the characteristics of interactions that sexual minority women have with their healthcare providers around sexual identity and health. Using a mixed-methods approach, both qualitative and quantitative data were gathered using an online survey. The sample included lesbian, bisexual, queer and pansexual women from across the USA. Qualitative and quantitative data were analysed concurrently, and qualitative themes were quantified and integrated into quantitative analyses. Identity disclosure, reasons for disclosing identity and characteristics of interactions with providers varied by identity, but often overlapped. Bisexual and pansexual participants were significantly less likely to disclose identity than lesbian participants. There were no significant differences related to age or ethnicity. Findings from this study have the potential to inform ethical medical practices and improve healthcare quality among sexual minority women.
Minority and minority-deaf professionals. How many and where are they?
Andrews, J F; Jordan, D L
1993-12-01
A survey of 6,043 professionals in 349 deaf education programs showed that 10.4% are from nonwhite or minority ethnic/cultural backgrounds. Of these minority professionals, 11.7% are deaf. Only 8 minority deaf administrators were found. Chi-square analyses showed that ethnic/cultural background and hearing loss were strongly associated with the type of program where the professionals were employed. More than half of the minority professionals worked in public schools. The District of Columbia, New York, and Maryland lead the country in the number of deaf professionals employed. More than half of all black deaf professionals work in either D.C. or New York. Texas leads the country in numbers of Hispanic professionals employed, and New Mexico has more Hispanic professionals than does California, New York, or Florida.
Report of the IAU/IAG Working Group on cartographic coordinates and rotational elements: 2006
Seidelmann, P.K.; Archinal, B.A.; A'Hearn, M.F.; Conrad, A.; Consolmagno, G.J.; Hestroffer, D.; Hilton, J.L.; Krasinsky, G.A.; Neumann, G.; Oberst, J.; Stooke, P.; Tedesco, E.F.; Tholen, D.J.; Thomas, P.C.; Williams, I.P.
2007-01-01
Every three years the IAU/IAG Working Group on Cartographic Coordinates and Rotational Elements revises tables giving the directions of the poles of rotation and the prime meridians of the planets, satellites, minor planets, and comets. This report introduces improved values for the pole and rotation rate of Pluto, Charon, and Phoebe, the pole of Jupiter, the sizes and shapes of Saturn satellites and Charon, and the poles, rotation rates, and sizes of some minor planets and comets. A high precision realization for the pole and rotation rate of the Moon is provided. The expression for the Sun's rotation has been changed to be consistent with the planets and to account for light travel time ?? 2007 Springer Science+Business Media B.V.
Mattinson, C.G.; Wooden, J.L.; Zhang, J.X.; Bird, D.K.
2009-01-01
In the southeastern part of the North Qaidam terrane, near Dulan, paragneiss hosts minor peridotite and UHP eclogite. Zircon geochronology and trace element geochemistry of three paragneiss samples (located within a ???3 km transect) indicates that eclogite-facies metamorphism resulted in variable degrees of zircon growth and recrystallization in the three samples. Inherited zircon core age groups at 1.8 and 2.5 Ga suggest that the protoliths of these rocks may have received sediments from the Yangtze or North China cratons. Mineral inclusions, depletion in HREE, and absence of negative Eu anomalies indicate that zircon U-Pb ages of 431 ?? 5 Ma and 426 ?? 4 Ma reflect eclogite-facies zircon growth in two of the samples. Ti-in-zircon thermometry results are tightly grouped at ???660 and ???600 ??C, respectively. Inclusions of metamorphic minerals, scarcity of inherited cores, and lack of isotopic or trace element inheritance demonstrate that significant new metamorphic zircon growth must have occurred. In contrast, zircon in the third sample is dominated by inherited grains, and rims show isotopic and trace element inheritance, suggesting solid-state recrystallization of detrital zircon with only minor new growth. ?? 2009 Elsevier Ltd.
NASA Astrophysics Data System (ADS)
Minguillón, María Cruz; Campos, Arturo Alberto; Cárdenas, Beatriz; Blanco, Salvador; Molina, Luisa T.; Querol, Xavier
2014-05-01
This work was carried out in the framework of the Cal-Mex project, which focuses on investigating the atmosphere along Mexico-California border region. Sampling was carried out at two sites located in Tijuana urban area: Parque Morelos and Metales y Derivados. PM2.5 and PM10 24 h samples were collected every three days from 17th May 2010 to 27th June 2010, and were used for gravimetric and chemical analyses (major and minor elements, inorganic ions, organic and elemental carbon) of PM. A subsequent Positive Matrix Factorization (PMF) analysis was performed. PM2.5 and PM10 average concentrations during Cal-Mex were relatively lower compared to usual annual averages. Trace elements concentrations recorded in the present study were lower than those recorded in Mexico City in 2006, with the exception of Pb at Metales y Derivados, attributed to the influence of a specific industrial source, which also includes As, Cd and Tl. Apart from this industrial source, both urban sites were found to be affected by similar sources with respect to bulk PM. Fine PM (PM2.5) was mainly apportioned by fueloil and biomass combustion and secondary aerosols, and road traffic. Coarse PM (PM2.5-10) was mainly apportioned by a mineral source (sum of road dust resuspension, construction emissions and natural soil) and fresh and aged sea salt. The road traffic was responsible for more than 60% of the fine elemental carbon and almost 40% of the fine organic matter.
Magmatic apatite - a window into melt evolution of the Dalgety pluton.
NASA Astrophysics Data System (ADS)
Pope, M. D.; Tailby, N.; Webster, J. D.
2017-12-01
The Dalgety Pluton is located in the Lachlan Fold Belt in southeastern Australia, and is a coarse grained, peraluminous, S-type, biotite granodiorite. Historically, pluton emplacement has been thought of as cooling from a single, large body of magma over a geologically quick period. Current studies suggest issues with this model and propose a slower, incremental model of emplacement in some settings (Glazner et al., 2004). This work proposes that the emplacement of the Dalgety Pluton occurred in incremental phases demonstrated through halogen, minor, and trace element concentrations in apatites. Apatites from 13 samples collected along a north-south transect of the pluton were analyzed using a 5-spectrometer Cameca SX-100 calibrated for seventeen elements (F, Na, Cl, P, Mg, Al, Si, Ca, S, K, Ti, Mn, Fe, Sr, Ba, La, and Ce) at the American Museum of Natural History. The majority of apatites are fluorapatites, having >50 % F, <15 % Cl, and <25 % OH (calculated from Ketchum et al., 2015). However, the concentrations of the halogens vary throughout the pluton with the highest Cl concentrations near the southern edge. Two of the minor elements, Mn and Fe, also show distinct variation with the lowest concentrations being 0.35 wt% in Mn and 0.25 wt% in Fe and the highest being 1.10 wt% and 0.95 wt%, respectively. Trace elements Ce and La vary as well with their highest concentrations being 0.29 wt% and 0.11 wt% and their lowest for both being below the detection limit of the electron probe. Elemental variation across the pluton is seen in the concentration of minor elements and halogens with a sharp increases at 10,000 meters and again at 21,000 meters from the southern rim of the pluton. Similar shifts in concentration are also seen in the trace elements, however the concentrations decrease at these distances. These wholesale elemental fluctuations in composition are indicative of a dramatic shift in melt composition supporting the hypothesis of multiple melt injection in the Dalgety Pluton. Reference: Glazner, A.F., Bartley, J.M., Coleman, D.S., Gray, W. and Taylor, R.Z., 2004. Are plutons assembled over millions of years by amalgamation from small magma chambers?. GSA today, 14(4/5), pp.4-12.
Enhancement of porous silicon photoluminescence property by lithium chloride treatment
NASA Astrophysics Data System (ADS)
Azaiez, Khawla; Zaghouani, Rabia Benabderrahmane; Khamlich, Saleh; Meddeb, Hosny; Dimassi, Wissem
2018-05-01
Porous silicon (PS) decorated by several nanostructured metal elements has still aroused interests as promising composites in many industrial applications. With the focus mainly on the synthesis, the aspect of stability against optical irradiation of such materials has so far not been thoroughly addressed. This work focuses primarily on the influence of lithium chloride solution (LiCl) treatment on the physical properties of PS. Variations in the structural and optoelectronic properties of PS were observed after immersion in (LiCl), as revealed by the obtained analyses. Moreover, enhanced photoluminescence (PL) property of the PS after passivation by lithium particles was clearly shown, and their presence on the surface of the microporous silicon was confirmed by FTIR spectroscopy and atomic force microscopy. An improvement of the minority carrier lifetime was also obtained, which was attributed to the decrease of the surface recombination velocity after LiCl treatment.
XAP, a program for deconvolution and analysis of complex X-ray spectra
Quick, James E.; Haleby, Abdul Malik
1989-01-01
The X-ray analysis program (XAP) is a spectral-deconvolution program written in BASIC and specifically designed to analyze complex spectra produced by energy-dispersive X-ray analytical systems (EDS). XAP compensates for spectrometer drift, utilizes digital filtering to remove background from spectra, and solves for element abundances by least-squares, multiple-regression analysis. Rather than base analyses on only a few channels, broad spectral regions of a sample are reconstructed from standard reference spectra. The effects of this approach are (1) elimination of tedious spectrometer adjustments, (2) removal of background independent of sample composition, and (3) automatic correction for peak overlaps. Although the program was written specifically to operate a KEVEX 7000 X-ray fluorescence analytical system, it could be adapted (with minor modifications) to analyze spectra produced by scanning electron microscopes, electron microprobes, and probes, and X-ray defractometer patterns obtained from whole-rock powders.
Factors Influencing the Trilingual Education in Leshan Ebian Yi Autonomous County
ERIC Educational Resources Information Center
Jian, Huang
2013-01-01
Language is symbolic of nationality culture (Claire, 2000). Trilingual education to the minority students is necessity for inheriting and developing their national culture. This survey studies the trilingual education in practice, analyses the existing trilingual education problems in Sichuan Leshan minority areas and indicates the prospect of the…
Off Balance: Youth, Race & Crime in the News. Building Blocks for Youth.
ERIC Educational Resources Information Center
Dorfman, Lori; Schiraldi, Vincent
This report assesses findings from content analyses on crime news, investigating whether news coverage reflects actual crime trends; how news coverage depicts minorities and crime; and whether news coverage disproportionately depicts minority youth as perpetrators. Data came from searches of criminal justice and communications databases, which…
Completely non-destructive elemental analysis of bulky samples by PGAA
NASA Astrophysics Data System (ADS)
Oura, Y.; Nakahara, H.; Sueki, K.; Sato, W.; Saito, A.; Tomizawa, T.; Nishikawa, T.
1999-01-01
NBAA (neutron beam activation analysis), which is a combination of PGAA and INAA by a single neutron irradiation, using an internal monostandard method is proposed as a very unique and promising method for the elemental analysis of voluminous and invaluable archaeological samples which do not allow even a scrape of the surface. It was applied to chinawares, Sueki ware, and bronze mirrors, and proved to be a very effective method for nondestructive analysis of not only major elements but also some minor elements such as boron that help solve archaeological problems of ears and sites of their production.
Micro-PIXE studies of Lupinus angustifolius L. after treatment of seeds with molybdenum
NASA Astrophysics Data System (ADS)
Przybylowicz, W. J.; Mesjasz-Przybylowicz, J.; Wouters, K.; Vlassak, K.; Combrink, N. J. J.
1997-02-01
An example of nuclear microprobe application in agriculture is presented. The NAC nuclear microprobe was used to determine quantitative elemental distribution of major, minor and trace elements in Lupinus angustifolius L. (Leguminosae) after treatment of seeds with molybdenum. Experiments were performed in order to establish safe concentration levels and sources of Mo in seed treatments. Elemental distributions in Mo-treated plants and in the non-treated control plants were studied in order to explain how Mo causes toxicity. Some specific regions of Mo and other main and trace elements enrichment were identified.
Li, Pengsheng; Huang, Yeen; Guo, Lan; Wang, Wanxin; Xi, Chuhao; Lei, Yiling; Luo, Min; Pan, Siyuan; Deng, Xueqing; Zhang, Wei-hong; Lu, Ciyong
2017-01-01
Objectives Recent studies have suggested that sexual minorities are more likely to have poor sleep quality. This study aims to explore sleep quality among sexual minority adolescents and examines the association between sexual minority status and sleep quality. Design Cross-sectional survey. Setting A total of 506 high schools in seven Chinese provinces. Participants A total of 150 822 students in grades 7–12 completed the questionnaires, and 123 459 students who reported being aware of their sexual orientation were included in analyses. Main outcome measures The Pittsburgh Sleep Quality Index, sexual attraction and school bullying victimisation. Results Of the 123 459 students who were analysed, 5.00% self-reported as sexual minorities. Only 26.67% of sexual minority students slept 8 or more hours/day, which is less than their heterosexual peers (35.70%; χ2=130.04, P<0.001). Of the total sample, 22.41% of the students reported poor sleep quality, and this prevalence was significantly higher in sexual minority students than in heterosexual students (32.56% vs 21.87%; χ2=281.70, P<0.001). After controlling for social demographics, lifestyle and depressive symptoms, sexual minority students had higher odds of poor sleep quality (adjusted OR=1.41, 95% CI 1.31 to 1.51) than their heterosexual peers. The indirect effect of school bullying victimisation (standardised β estimate=0.007, 95% CI 0.006 to 0.009) was significant, indicating that school bullying victimisation partially mediated the association between sexual minority status and sleep quality. Conclusions Our study suggested that poor sleep quality was common in sexual minority adolescents, and more attention should be paid to sleep problems in this population. Conducting interventions to reduce school bullying behaviours is an important step to improving sleep quality in sexual minority adolescents. Further, studies are warranted that focus on the risk factors and mechanisms of and interventions for sleep problems in sexual minority adolescents. PMID:29282258
NASA Astrophysics Data System (ADS)
Sanderman, J.; Baisden, W. T.; Creamer, C.; Farrell, M.; Fallon, S.
2016-12-01
Carbonatites and alkaline intrusions are important sources of REEs. Environmental risks related to these deposit types have been assessed through literature review and evaluation of the geochemical properties of representative samples of mill tailings and their leachates. The main ore mineral in carbonatite deposits is bastnasite [(Ce,La)(CO3)F], which is found with dolomite and calcite ( 65 %), barite (20 - 25 %), plus a number of minor accessory minerals including sulfides such as galena and pyrite. Generally, alkaline intrusion-related REE deposits either occur in layered complexes or with dikes and veins cutting alkaline intrusions. Such intrusions have a more diverse group of REE ore minerals that include fluorcarbonates, oxides, silicates, and phosphates. Ore also can include minor calcite and iron (Fe), lead (Pb), and zinc (Zn) sulfides. The acid-generating potential of both deposit types is low because of a predominance of carbonate minerals in the carbonatite deposits, the presence of feldspars and minor calcite in alkaline intrusion-related deposits, and to only minor to trace occurrence of potentially acid-generating sulfide minerals. Both deposit types, however, are produced by igneous and hydrothermal processes that enrich high-field strength, incompatible elements, which typically are excluded from common rock-forming minerals. Elements such as yttrium (Y), niobium Nb), zirconium (Zr), hafnium (Hf), tungsten (W), titanium (Ti), tantalum (Ta), scandium (Sc), thorium (Th), and uranium (U) can be characteristic of these deposits and may be of environmental concern. Most of these elements, including the REEs, but with the exception of U, have low solubilities in water at the near-neutral pH values expected around these deposits. Mill tailings from carbonatite deposits can exceed residential soil and sediment criteria for Pb, and leachates from mill tailings can exceed drinking water guidelines for Pb. The greatest environmental challenges, however, are linked to the presence of Th and U, although mineral hosts for these elements are moderately unreactive in the environment. Both deposit types can have mill tailings that exceed residential soil criteria for U. Uranium can be recovered as a byproduct to mitigate its environmental effects, but Th remains a waste product that requires management.
Newcomb, Michael E; Ryan, Daniel T; Garofalo, Robert; Mustanski, Brian
2015-10-01
Men who have sex with men (MSM) are disproportionately impacted by the HIV/AIDS epidemic in the United States. The epidemic is not evenly distributed across MSM, and young racial minority MSM experience the highest rate of new infections. Race-based sexual stereotyping is not uncommon among MSM, and it may contribute to the isolation of racial minority sexual networks, which has been found to contribute to increased HIV incidence in Black MSM. The goals of these analyses were to describe the race-based sexual preferences and stereotypes of racially diverse young MSM (YMSM), and to examine whether endorsement of sexual stereotypes was associated with sexual risk behavior when having sex with partners of the stereotyped race. Data were taken from Crew 450, an ongoing longitudinal study of a syndemic of psychosocial health issues linked to HIV among YMSM in Chicago and surrounding areas. Analyses utilized data from three study waves, and longitudinal analyses were conducted with Hierarchical Linear Modeling. YMSM generally endorsed same-race preferences for sexual partners. Black partners were rated highest in displaying stereotypically dominant characteristics and in likelihood of taking the top/insertive sex role, while Latino partners were rated the highest in likelihood of sex being hot and passionate. White partners were rated lowest on each of these domains. Longitudinal analyses found that endorsement of these stereotypes had important implications for the rate of condomless receptive and insertive anal sex with racial minority partners. Findings suggest that sexual stereotypes may contribute to the isolation of racial minority sexual networks.
Newcomb, Michael E.; Ryan, Daniel T.; Garofalo, Robert; Mustanski, Brian
2015-01-01
Men who have sex with men (MSM) are disproportionately impacted by the HIV/AIDS epidemic in the United States. The epidemic is not evenly distributed across MSM, and young racial minority MSM experience the highest rate of new infections. Race-based sexual stereotyping is not uncommon among MSM, and it may contribute to the isolation of racial minority sexual networks, which has been found to contribute to increased HIV incidence in Black MSM. The goals of these analyses were to describe the race-based sexual preferences and stereotypes of racially-diverse young MSM (YMSM), and to examine whether endorsement of sexual stereotypes was associated with sexual risk behavior when having sex with partners of the stereotyped race. Data were taken from Crew 450, an ongoing longitudinal study of a syndemic of psychosocial health issues linked to HIV among YMSM in Chicago and surrounding areas. Analyses utilized data from three study waves, and longitudinal analyses were conducted with Hierarchical Linear Modeling. YMSM generally endorsed same-race preferences for sexual partners. Black partners were rated highest in displaying stereotypically dominant characteristics and in likelihood of taking the top/insertive sex role, while Latino partners were rated the highest in likelihood of sex being hot and passionate. White partners were rated lowest on each of these domains. Longitudinal analyses found that endorsement of these stereotypes had important implications for the rate of condomless receptive and insertive anal sex with racial minority partners. Findings suggest that sexual stereotypes may contribute to the isolation of racial minority sexual networks. PMID:26116010
Magnesioferrite from the Cretaceous-Tertiary boundary, Caravaca, Spain
Bohor, B.F.; Foord, E.E.; Ganapathy, R.
1986-01-01
Magnesioferrite grading toward magnetite has been identified as a very small but meaningful constituent of the basal iron-rich portion of the Cretaceous-Tertiary (K-T) boundary clay at the Barranco del Gredero section, Caravaca, Spain. This spinel-type phase and others of the spinel group, found in K-T boundary clays at many widely separated sites, have been proposed as representing unaltered remnants of ejecta deposited from an earth-girdling dust cloud formed from the impact of an asteroid or other large bolide at the end of the Cretaceous period. The magnesioferrite occurs as euhedral, frequently skeletal, micron-sized octahedral crystals. The magnesioferrite contains 29 ?? 11 ppb Ir, which accounts for only part of the Ir anomaly at this K-T boundary layer (52 ?? 1 ppb Ir). Major element analyses of the magnesioferrite show variable compositions. Some minor solid solution exists toward hercynite-spinel and chromite-magnesiochromite. A trevorite-nichromite (NiFe2O4NiCr2O4) component is also present. The analyses are very similar to those reported for sites at Furlo and Petriccio, Umbria, Italy. On the basis of the morphology and general composition of the magnesioferrite grains, rapid crystallization at high temperature is indicated, most likely directly from a vapor phase and in an environment of moderate oxygen fugacity. Elemental similarity with metallic alloy injected into rocks beneath two known impact craters suggests that part of the magnesioferrite may be derived from the vaporized chondritic bolide itself, or from the mantle; there is no supporting evidence for its derivation from crustal target rocks. ?? 1986.
Zhu, Rui; Zander, Thomas; Dreischarf, Marcel; Duda, Georg N; Rohlmann, Antonius; Schmidt, Hendrik
2013-04-26
Mostly simplified loads were used in biomechanical finite element (FE) studies of the spine because of a lack of data on muscular physiological loading. Inverse static (IS) models allow the prediction of muscle forces for predefined postures. A combination of both mechanical approaches - FE and IS - appears to allow a more realistic modeling. However, it is unknown what deviations are to be expected when muscle forces calculated for models with rigid vertebrae and fixed centers of rotation, as generally found in IS models, are applied to a FE model with elastic vertebrae and discs. The aim of this study was to determine the effects of these disagreements. Muscle forces were estimated for 20° flexion and 10° extension in an IS model and transferred to a FE model. The effects of the elasticity of bony structures (rigid vs. elastic) and the definition of the center of rotation (fixed vs. non-fixed) were quantified using the deviation of actual intervertebral rotation (IVR) of the FE model and the targeted IVR from the IS model. For extension, the elasticity of the vertebrae had only a minor effect on IVRs, whereas a non-fixed center of rotation increased the IVR deviation on average by 0.5° per segment. For flexion, a combination of the two parameters increased IVR deviation on average by 1° per segment. When loading FE models with predicted muscle forces from IS analyses, the main limitations in the IS model - rigidity of the segments and the fixed centers of rotation - must be considered. Copyright © 2013 Elsevier Ltd. All rights reserved.
The Dart estuary, Devon, UK: a case study of chemical dynamics and pollutant mobility
NASA Astrophysics Data System (ADS)
Schuwerack, P.-M. M.; Neal, M.; Neal, C.
2007-01-01
Water, sediments and gill and digestive gland tissues of adult common shore crab (Carcinus maenas), collected at Noss Marina, Sandquay (Britannia Royal Naval College), the Dartmouth Pier, Warfleet Cove and Sugary Cove in the Dart estuary, Devon, UK, were analysed for major, minor and trace elements in spring 2004. Total acid-available measurements analysed included the truly dissolved component and acid-available sediments. Trace metal concentrations are associated largely with particulate and micro-particulate/colloidal phases, the latter being able to pass through standard filter papers. Wide ranges of chemical concentrations were found in the water, sediments and tissues at all the locations. In the water column, 48% of the variance is linked to the sea-salt component (Cl, Na, K, Ca, Mg, B, Li and Sr) and the sediment-associated acid-available fractions are linked to Fe-rich lithogenous materials (Ba, Co, Cu, Fe, Mn, V and Zn). In the sediments, trace elements of Cd, Co, Cr, Fe, Pb, Mn, Ni and V are correlated with the sea salts and associated with the fraction of fine sediments within the total sediment. In the gills and the digestive gland tissues of crabs, high concentrations of Al, Cu and Fe are found and there are correlations between acid-available trace metals of Cu, Cr, Fe, Mn, Ni, Sr and Zn. The relationships between trace metal contaminants, their site-specific concentrations, their temporal and spatial variability and the effects of human activities, such as moorland/agriculture with historic mining and recreational activities in the lower Dart estuary, are discussed.
NASA Astrophysics Data System (ADS)
Togunwa, Olayinka S.; Abdullah, Wan H.
2017-08-01
The Neogene strata of the onshore West Baram Province of NW Borneo contain organic rich rock formations particularly within the Sarawak basin. This basin is a proven prolific oil and gas province, thus has been a subject of great interest to characterise the nature of the organic source input and depositional environment conditions as well as thermal maturation. This study is performed on outcrop samples of Lambir, Miri and Tukau formations, which are of stratigraphic equivalence to the petroleum bearing cycles of the offshore West Baram delta province in Sarawak. The investigated mudstone samples are organic rich with a total organic carbon (TOC) content of more than 1.0 wt.%. The integration of elemental and molecular analyses indicates that there is no significant variation in the source input between these formations. The investigated biomarkers parameters achieved from acyclic isoprenoids, terpanes and steranes biomarkers of a saturated hydrocarbon biomarkers revealed that these sediments contain high contribution of land plants with minor marine organic matter input that was deposited and preserved under relatively oxic to suboxic conditions. This is further supported by low total sulphur (TS), high TOC/TN ratios, source and redox sensitive trace elements (V, Ni, Cr, Co and Mo) concentrations and their ratios, which suggest terrigenous source input deposited under oxic to suboxic conditions. Based on the analysed biomarker thermal maturity indicators, it may be deduced that the studied sediments are yet to enter the maturity stage for hydrocarbon generation, which is also supported by measured vitrinite reflectance values of 0.39-0.48% Ro.
Pfaff, Katharina; Koenig, Alan; Wenzel, Thomas; Ridley, Ian; Hildebrandt, Ludwig H.; Leach, David L.; Markl, Gregor
2011-01-01
Various models have been proposed to explain the formation mechanism of colloform sphalerite, but the origin is still under debate. In order to decipher influences on trace element incorporation and sulfur isotope composition, crystalline and colloform sphalerite from the carbonate-hosted Mississippi-Valley Type (MVT) deposit near Wiesloch, SW Germany, were investigated and compared to sphalerite samples from 52 hydrothermal vein-type deposits in the Schwarzwald ore district, SW Germany to study the influence of different host rocks, formation mechanisms and fluid origin on trace element incorporation. Trace and minor element incorporation in sphalerite shows some correlation to their host rock and/or origin of fluid, gangue, paragenetic minerals and precipitation mechanisms (e.g., diagenetic processes, fluid cooling or fluid mixing). Furthermore, crystalline sphalerite is generally enriched in elements like Cd, Cu, Sb and Ag compared to colloform sphalerite that mainly incorporates elements like As, Pb and Tl. In addition, sulfur isotopes are characterized by positive values for crystalline and strongly negative values for colloform sphalerite. The combination of trace element contents, typical minerals associated with colloform sphalerite from Wiesloch, sulfur isotopes and thermodynamic considerations helped to evaluate the involvement of sulfate-reducing bacteria in water-filled karst cavities. Sulfate-reducing bacteria cause a sulfide-rich environment that leads in case of a metal-rich fluid supply to a sudden oversaturation of the fluid with respect to galena, sphalerite and pyrite. This, however, exactly coincides with the observed crystallization sequence of samples involving colloform sphalerite from the Wiesloch MVT deposit.
Wang, Zhi-gang; Yu, Hong-mei
2012-01-01
The content of the elements C, H, O and N in Jinhua bergamot was analysed by using Vario III elemental analyser, the bergamot sample was scanned by using X-ray fluorescence spectrometer with PW2400 wavelength dispersion, and the content of the elements Mg, Al, P, S, Cl, K, Ca, Mn, Fe and Sr was analysed by using IQ+ analytical method. It turned out that the result is more ideal if the content of the elements C, H, O and N is processed as fix phase, and the analytical result is more ideal if, to prevent the sample skin from coming off, the sample is wrapped with mylar film with the film coefficient adjusted.
Bioaccumulation of Uranium and Thorium by Lemna minor and Lemna gibba in Pb-Zn-Ag Tailing Water.
Sasmaz, Merve; Obek, Erdal; Sasmaz, Ahmet
2016-12-01
This study focused on the ability of Lemna minor and Lemna gibba to remove U and Th in the tailing water of Keban, Turkey. These plants were placed in tailing water and individually fed to the reactors designed for these plants. Water and plant samples were collected daily from the mining area. The plants were ashed at 300°C for 1 day and analyzed by ICP-MS for U and Th. U was accumulated as a function of time by these plants, and performances between 110 % and 483 % for L. gibba, and between 218 % and 1194 % for L. minor, were shown. The highest Th accumulations in L. minor and L. gibba were observed at 300 % and 600 % performances, respectively, on the second day of the experiment. This study indicated that both L. gibba and L. minor demonstrated a high ability to remove U and Th from tailing water polluted by trace elements.
Spears, D.A.; Tewalt, S.J.
2009-01-01
The Parkgate coal of Langsettian age in the Yorkshire-Nottinghamshire coalfield is typical of many coals in the UK in that it has a high sulphur (S) content. Detailed information on the distribution of the forms of S, both laterally and vertically through the seam, was known from previous investigations. In the present work, 38 interval samples from five measured sections of the coal were comprehensively analysed for major, minor and trace elements and the significance of the relationships established using both raw and centered log transformed data. The major elements are used to quantify the variations in the inorganic and organic coal components and determine the trace element associations. Pyrite contains nearly all of the Hg, As, Se, Tl and Pb and is also the major source of the Mo, Ni, Cd and Sb. The clays contain the following elements in decreasing order of association: Rb, Cs, Li, Ga, U, Cr, V, Sc, Y, Bi, Cu, Nb, Sn, Te and Th. Nearly all of the Rb is present in the clay fraction, whereas for elements such as V, Cu and U, a significant amount is thought to be present in the organic matter, based on the K vs trace element regression equations. Only Ge, and possibly Be, would appear to have a dominant organic source. The trace element concentrations are calculated for pyrite, the clay fraction and organic matter. For pyrite it is noted that concentrations agree with published data from the Yorkshire-Nottinghamshire coalfield and also that Tl concentrations (median of 0.33 ppm) in the pyrite are greater than either Hg or Cd. Unlike these elements, Tl has attracted less attention and possibly more information is needed on its anthropogenic distribution and impacts on man and the environment. A seawater source is thought to be responsible for the high concentrations of S, Cl and the non-detrital trace elements in the Parkgate coal. Indicative of the seawater control is the Th/U ratio, which expresses the detrital to non-detrital element contributions. Using other elements, similar ratios can be calculated, which in combination offer greater interpretative value. ?? 2009 Elsevier B.V.
NASA Astrophysics Data System (ADS)
Eshaghi Malekshah, Rahime; Salehi, Mehdi; Kubicki, Maciej; Khaleghian, Ali
2017-12-01
Two novel mononuclear complexes, [Zn (TTA) (bipy)Cl] (1) and [Zn (TTA) (phen)Cl] (2) (TTA = 4,4,4-Trifluoro-1-(2-furyl)-1,3-butanedione, phen = 1,10-phenanthroline and bipy 2, 2ʹ-bipyridine), were synthesized and fully characterized by elemental analyses, 1H NMR, UV-Vis, FTIR spectroscopy, and conductivity measurements. The crystal structures of these two mono-nuclear zinc (II) complexes were determined by X-ray single-crystal diffraction. The result of X-ray diffraction analyses revealed that both complexes have distorted tetragonal-pyramid structures. In MTT cytotoxicity studies, these Zn (II) complexes exhibited antitumor activity against MCF-7 and MKN-45 cell lines. It was also found that the proliferation rate of MCF-7 and MKN-45 cells decreased after treatment with the above-mentioned complexes. In addition, the apoptosis-inducing activity was assessed by AO/EB (Acridine Orange/Ethidium bromide) staining assay and found that they have the potential to act as effective metal-based anticancer drugs. Finally, the molecular docking studies showed that complex 2 strongly binds through minor groove with DNA by relative binding energy -7.33 kcal mol-1.
Unsteady load on an oscillating Kaplan turbine runner
NASA Astrophysics Data System (ADS)
Puolakka, O.; Keto-Tokoi, J.; Matusiak, J.
2013-02-01
A Kaplan turbine runner oscillating in turbine waterways is subjected to a varying hydrodynamic load. Numerical simulation of the related unsteady flow is time-consuming and research is very limited. In this study, a simplified method based on unsteady airfoil theory is presented for evaluation of the unsteady load for vibration analyses of the turbine shaft line. The runner is assumed to oscillate as a rigid body in spin and axial heave, and the reaction force is resolved into added masses and dampings. The method is applied on three Kaplan runners at nominal operating conditions. Estimates for added masses and dampings are considered to be of a magnitude significant for shaft line vibration. Moderate variation in the added masses and minor variation in the added dampings is found in the frequency range of interest. Reference results for added masses are derived by solving the boundary value problem for small motions of inviscid fluid using the finite element method. Good correspondence is found in the added mass estimates of the two methods. The unsteady airfoil method is considered accurate enough for design purposes. Experimental results are needed for validation of unsteady load analyses.
Improvement of sensitivity in PIGE analysis of steels by neutron-gamma coincidences measurement
NASA Astrophysics Data System (ADS)
Ene, Antoaneta
2004-07-01
In this work the sensitivities of minor elements in a standard steel sample EURONORM-CRM No. 085-1 irradiated with beams of 5.5 MeV protons and 5 MeV deuterons have been determined both by regular proton- (p-PIGE) and deuteron-induced prompt gamma-ray emission (d-PIGE) methods and with the selection of the (p, n) and (d, n) reaction channels, measuring the neutron-gamma coincidences. A check on the elemental composition of the steel standard has also been carried out using combined INAA and PIXE and quantitative determinations have been done for some elements whose concentrations were not specified by the manufacturer, such as Al, As, Cr, Mo, Na, Ni, W. This complex study has resulted in a significant improvement of the sensitivities for some minor elements in steel by reducing the background and increasing the peak-to-background ratio in the coincident prompt gamma-rays spectra as a result of the elimination of the competing nuclear reactions originating from isotopes of the adjacent elements in the periodic table, present in the steel target. This extension of the PIGE method could be adapted by any analyst with the necessary equipment for the analysis of a wide variety of matrices that are refractory enough to withstand the heating effect of the bombarding beam, taking into account that this type of experiment requires longer irradiation times.
Donohue, Patrick H; Hill, Eddy; Huss, Gary R
2018-02-01
Pallasite meteorites, which consist primarily of olivine and metal, may be remnants of disrupted core-mantle boundaries of differentiated asteroids or planetesimals. The early thermal histories of pallasites are potentially recorded by minor- and trace-element zonation in olivine. However, constraining this history requires knowledge of element behavior under the conditions of pallasite formation, which is lacking for many of the main elements of interest (e.g., Co, Cr, Mn). In this study, we experimentally determined metal/olivine partition coefficients for Fe, Ni, Co, Cr, and Mn in a pallasite analogue at subsolidus temperatures. Metal/olivine partition coefficients ( K M ) increase in the order K Mn < K Cr < 1 < K Fe < K Co < K Ni , with five orders of magnitude separating K Mn from K Ni . Transition metals also become more siderophile with increasing experimental temperature (900 to 1550°C). The experiments incidentally produced diffusion profiles in olivine for these elements; Our results suggest they diffuse through olivine at similar rates. Core compositions of pallasite olivines are consistent with high-temperature equilibration with FeNi-metal. Olivine zonation toward crystal rims varies significantly for the investigated transition metals. We suggest rim zonation results from partial re-equilibration during late stage crystallization of minor phases (e.g., chromite, phosphates). This re- equilibration occurred over short timescales relative to overall pallasite cooling, likely tied to initial cooling rates on the order of 100-300°C/Myr.
NASA Astrophysics Data System (ADS)
Donohue, Patrick H.; Hill, Eddy; Huss, Gary R.
2018-02-01
Pallasite meteorites, which consist primarily of olivine and metal, may be remnants of disrupted core-mantle boundaries of differentiated asteroids or planetesimals. The early thermal histories of pallasites are potentially recorded by minor- and trace-element zonation in olivine. However, constraining this history requires knowledge of element behavior under the conditions of pallasite formation, which is lacking for many of the main elements of interest (e.g., Co, Cr, Mn). In this study, we experimentally determined metal/olivine partition coefficients for Fe, Ni, Co, Cr, and Mn in a pallasite analogue at subsolidus temperatures. Metal/olivine partition coefficients (KM) increase in the order KMn < KCr < 1 < KFe < KCo < KNi, with five orders of magnitude separating KMn from KNi. Transition metals also become more siderophile with increasing experimental temperature (900-1550 °C). The experiments incidentally produced diffusion profiles in olivine for these elements; our results suggest they diffuse through olivine at similar rates. Core compositions of pallasite olivines are consistent with high-temperature equilibration with FeNi-metal. Olivine zonation toward crystal rims varies significantly for the investigated transition metals. We suggest rim zonation results from partial re-equilibration during late stage crystallization of minor phases (e.g., chromite, phosphates). This re-equilibration occurred over short timescales relative to overall pallasite cooling, likely tied to initial cooling rates on the order of 100-300 °C/Myr.
Barik, Saroja K; Muduli, Pradipta R; Mohanty, Bita; Rath, Prasanta; Samanta, Srikanta
2018-01-01
The article presents first systematic report on the concentration of selected major elements [iron (Fe) and manganese (Mn)] and minor elements [zinc (Zn), copper (Cu), chromium (Cr), lead (Pb), nickel (Ni), and cobalt (Co)] from the core sediment of Chilika Lake, India. The analyzed samples revealed higher content of Pb than the background levels in the entire study area. The extent of contamination from minor and major elements is expressed by assessing (i) the metal enrichments in the sediment through the calculations of anthropogenic factor (AF), pollution load index (PLI), Enrichment factor (EF), and geoaccumulation index (Igeo) and (ii) potential biological risks by the use of sediment quality guidelines like effect range median (ERM) and effect range low (ERL) benchmarks. The estimated indices indicated that sediment is enriched with Pb, Ni, Cr, Cu and Co. The enrichment of these elements seems to be due to the fine granulometric characteristics of the sediment with Fe and Mn oxyhydroxides being the main metal carriers and fishing boats using low grade paints, fuel, and fishing technology using lead beads fixed to fishing nets. Trace element input to the Chilika lake needs to be monitored with due emphasis on Cr and Pb contaminations since the ERM and ERL benchmarks indicated potential biological risk with these metals.
Depoliticizing Minority Admissions through Predicted Graduation Equations. AIR Forum 1982 Paper.
ERIC Educational Resources Information Center
Sanford, Timothy R.
The way that the University of North Carolina, Chapel Hill, has tried to depoliticize minority admissions through the use of predicted graduation equations that are race specific is examined. Multiple regression and discriminant analyses were used with nine independent variables (primarily academic) to predict graduation status of 1974 entering…
ERIC Educational Resources Information Center
Pierce, Margaret E.; Wechsler-Zimring, Adrianna; Noam, Gil; Wolf, Maryanne; Katzir, Tami
2013-01-01
This study examined the potentially compounding effect of language minority (LM) status on problem behaviors among urban second and third grade-level poor readers. Univariate analyses showed that a disproportionate percentage of both LM and English monolingual (L1) poor readers already displayed clinically significant levels of anxiety, social…
ERIC Educational Resources Information Center
Santos, Jose L.; Cabrera, Nolan L.; Fosnacht, Kevin J.
2010-01-01
Authors examine the proportion of undergraduate applications, admissions, and enrollments preceding, during, and after Proposition 209 while accounting for the relative growth in University of California eligibility for underrepresented minorities (URMs). They employed standard deviation analyses to measure dispersion of the URMs to non-URMs.…
Academic Performance of Language-Minority Students and All-Day Kindergarten: A Longitudinal Study
ERIC Educational Resources Information Center
Chang, Mido
2012-01-01
This longitudinal study examined the effect of all-day kindergarten programs on the academic achievement of students from racial language minority and low socioeconomic class. The study employed a series of 3-level longitudinal multilevel analyses using a nationally representative database, the Early Childhood Longitudinal Study (ECLS). The study…
NASA Technical Reports Server (NTRS)
Righter, M.; Lapen, T.; Righter, K.
2008-01-01
Achondritic meteorites are a diverse group of meteorites that formed by igneous activity in asteroids. These meteorites can provide important information about early differentiation processes on asteroidal bodies. The howardite-eucrite-diogenite (HED) meteorites, the largest group of achondrites, are the only group of meteorites for which a potential parent body has been identified (4 Vesta) [e.g., 1]. Mesosiderites are stony-iron meteorites composed of roughly equal amounts of metal and silicates and silicates are broadly similar to HED meteorites [2]. They may have been formed by impact-mixing of crustal and core materials of differentiated meteorite parent bodies. Chemical and oxygen isotopic compositional data suggest that the HED meteorites and silicate portions of mesosiderites originated on the same or closely related parent bodies. Pallasites and IIIAB irons also have similar oxygen isotope compositions and have been thought to be related to the HEDs [3,4]. However, recent high resolution analyses have shown that pallasites and HED's have different oxygen isotopic values, but mesosiderites and HED s have the same isotope compositions implying a close connection [5]. QUE 93148 is a small (1.1g) olivine-rich (mg 86) achondrite that contains variable amounts of orthopyroxenene (mg 87) and kamacite (6.7 wt% Ni), with minor augite [6]. This meteorite was originally classified as a lodranite [7], but it s oxygen isotopic composition precludes a genetic relationship to the acapulcoites and lodranites. And also this meteorite has a lower Mn/Mg ratio than any major group of primitive or evolved achondrites and suggested that QUE 93148 may be a piece of the deep mantle of the HED parent body [6]. To better understand the relationship between HED s, mesosiderites and related achondrites, we have measured trace elements in the individual metallic and silicate phases. In this study, abundances of a suite of elements were measured for the unusual mesosiderite RKPA 79015 and a ungrouped achondrite QUE93148.
NASA Astrophysics Data System (ADS)
Hatipoğlu, Murat; Kibar, Rana; Çetin, Ahmet; Can, Nurdoğan; Helvacı, Cahit; Derin, H.
2011-07-01
Amethyst crystals on matrix specimens from the Dursunbey-Balıkesir region in Turkey have five representative purple color zonings: dark purple, light purple, lilac, orchid, and violet. The purple color zonings have been analyzed with optical absorption spectra in the visible wavelength region, chemical full trace element analyses (inductively coupled plasma-atomic emission spectroscopy and inductively coupled plasma-mass spectroscopy), and scanning electron microscopic images with high magnification. It can be proposed that the production of the purple color in amethyst crystals is due to three dominant absorption bands centered at 375, 530, and 675 nm, respectively. In addition, the purple color zonings are also due to four minor absorption bands centered at 435, 480, 620, and 760 nm. X-ray diffraction graphics of the investigated amethyst crystals indicate that these crystals are composed of a nearly pure alpha-quartz phase and do not include any moganite silica phase and/or other mineral implications. Trace element analyses of the amethyst crystals show five representative purple color zonings, suggesting that the absorption bands can be mainly attributed to extrinsic defects (chemical impurities). However, another important factor that influences all structural defects in amethyst is likely to be the gamma irradiation that exists during amethyst crystallization and its inclusion in host materials. This gamma irradiation originates from the large underlying intrusive granitoid body in the region of amethyst formation. Irradiation modifies the valence values of the impurity elements in the amethyst crystals. It is observed that the violet-colored amethyst crystals have the most stable and the least reversible coloration when exposed to strong light sources. This situation can be related to the higher impurity content of Fe (2.50 ppm), Co (3.1 ppm), Ni (38 ppm), Cu (17.9 ppm), Zn (10 ppm), Zr (3.9 ppm), and Mo (21.8 ppm).
Rare Earth Geochemistry of Rock Core form WY Reservoirs
Quillinan, Scott; Bagdonnas, Davin; McLaughlin, J. Fred; Nye, Charles
2016-10-01
These data include major, minor, trace and rare earth element concentration of geologic formations in Wyoming oil and gas fields. *Note - Link below contains updated version of spreadsheet (6/14/2017)
Maksimova, Victoria V; Mazukhina, Svetlana I; Cherepanova, Tatiana A; Gorbacheva, Tamara T
2017-07-29
The physical-chemical stage of marginal filters in minor rivers of the White Sea catchment area by the example of the Umba River, flowing to Kandalaksha Gulf, has been explored. Application of the method of physical-chemical modeling on the basis of field data allowed establishing migration forms of a number of elements in the "river-sea" system and deposition of solid phases when mixing waters. The mixing of river and sea water is accompanied by the sedimentation of predominantly goethite, hydromuscovite, and hydroxylapatite. Sediments in mixing river and sea waters were found to be mainly composed by goethite, hydromuscovite, and hydroxylapatite. The research has added to the knowledge of the role of the abiotic part in the marginal filters of small rivers in the Arctic.
NASA Astrophysics Data System (ADS)
Talhelm, A. F.; Pregitzer, K. S.; Burton, A. J.; Xia, M.; Zak, D. R.
2017-12-01
The elemental and biochemical composition of plant tissues is an important influence on primary productivity, decomposition, and other aspects of biogeochemistry. Human activity has greatly altered biogeochemical cycles in ecosystems downwind of industrialized regions through atmospheric nitrogen deposition, but most research on these effects focuses on individual elements or steps in biogeochemical cycles. Here, we quantified pools and fluxes of biomass, the four major organic elements (carbon, oxygen, hydrogen, nitrogen), four biochemical fractions (lignin, structural carbohydrates, cell walls, and soluble material), and energy in a mature northern hardwoods forest in Michigan. We sampled the organic and mineral soil, fine and coarse roots, leaf litter, green leaves, and wood for chemical analyses. We then combined these data with previously published and archival information on pools and fluxes within this forest, which included replicated plots receiving either ambient deposition or simulated nitrogen deposition (3 g N m-2 yr-1 for 18 years). Live wood was the largest pool of energy and all elements and biochemical fractions. However, the production of wood, leaf litter, and fine roots represented similar fluxes of carbon, hydrogen, oxygen, cell wall material, and energy, while nitrogen fluxes were dominated by leaf litter and fine roots. Notably, the flux of lignin via fine roots was 70% higher than any other flux. Experimental nitrogen deposition had relatively few significant effects, increasing foliar nitrogen, increasing the concentration of lignin in the soil organic horizon and decreasing pools of all elements and biochemical fractions in the soil organic horizon except nitrogen, lignin, and structural carbohydrates. Overall, we found that differences in tissue chemistry concentrations were important determinants of ecosystem-level pools and fluxes, but that nitrogen deposition had little effect on concentrations, pools, or fluxes in this mature forest. Disclaimer: The views expressed in this poster are those of the authors and do not necessarily represent the views or policies of the U.S. EPA.
Spörlein, Christoph; Schlueter, Elmar
2018-01-01
Here we examine a conceptualization of immigrant assimilation that is based on the more general notion that distributional differences erode across generations. We explore this idea by reinvestigating the efficiency-equality trade-off hypothesis, which posits that stratified education systems educate students more efficiently at the cost of increasing inequality in overall levels of competence. In the context of ethnic inequality in math achievement, this study explores the extent to which an education system's characteristics are associated with ethnic inequality in terms of both the group means and group variances in achievement. Based on data from the 2012 PISA and mixed-effect location scale models, our analyses revealed two effects: on average, minority students had lower math scores than majority students, and minority students' scores were more concentrated at the lower end of the distribution. However, the ethnic inequality in the distribution of scores declined across generations. We did not find compelling evidence that stratified education systems increase mean differences in competency between minority and majority students. However, our analyses revealed that in countries with early educational tracking, minority students' math scores tended to cluster at the lower end of the distribution, regardless of compositional and school differences between majority and minority students.
Spörlein, Christoph
2018-01-01
Here we examine a conceptualization of immigrant assimilation that is based on the more general notion that distributional differences erode across generations. We explore this idea by reinvestigating the efficiency-equality trade-off hypothesis, which posits that stratified education systems educate students more efficiently at the cost of increasing inequality in overall levels of competence. In the context of ethnic inequality in math achievement, this study explores the extent to which an education system’s characteristics are associated with ethnic inequality in terms of both the group means and group variances in achievement. Based on data from the 2012 PISA and mixed-effect location scale models, our analyses revealed two effects: on average, minority students had lower math scores than majority students, and minority students’ scores were more concentrated at the lower end of the distribution. However, the ethnic inequality in the distribution of scores declined across generations. We did not find compelling evidence that stratified education systems increase mean differences in competency between minority and majority students. However, our analyses revealed that in countries with early educational tracking, minority students’ math scores tended to cluster at the lower end of the distribution, regardless of compositional and school differences between majority and minority students. PMID:29494677
FCRD Advanced Reactor (Transmutation) Fuels Handbook
DOE Office of Scientific and Technical Information (OSTI.GOV)
Janney, Dawn Elizabeth; Papesch, Cynthia Ann
2016-09-01
Transmutation of minor actinides such as Np, Am, and Cm in spent nuclear fuel is of international interest because of its potential for reducing the long-term health and safety hazards caused by the radioactivity of the spent fuel. One important approach to transmutation (currently being pursued by the DOE Fuel Cycle Research & Development Advanced Fuels Campaign) involves incorporating the minor actinides into U-Pu-Zr alloys, which can be used as fuel in fast reactors. U-Pu-Zr alloys are well suited for electrolytic refining, which leads to incorporation rare-earth fission products such as La, Ce, Pr, and Nd. It is, therefore, importantmore » to understand not only the properties of U-Pu-Zr alloys but also those of U-Pu-Zr alloys with concentrations of minor actinides (Np, Am) and rare-earth elements (La, Ce, Pr, and Nd) similar to those in reprocessed fuel. In addition to requiring extensive safety precautions, alloys containing U, Pu, and minor actinides (Np and Am) are difficult to study for numerous reasons, including their complex phase transformations, characteristically sluggish phasetransformation kinetics, tendency to produce experimental results that vary depending on the histories of individual samples, rapid oxidation, and sensitivity to contaminants such as oxygen in concentrations below a hundred parts per million. Although less toxic, rare-earth elements such as La, Ce, Pr, and Nd are also difficult to study for similar reasons. Many of the experimental measurements were made before 1980, and the level of documentation for experimental methods and results varies widely. It is, therefore, not surprising that little is known with certainty about U-Pu-Zr alloys, particularly those that also contain minor actinides and rare-earth elements. General acceptance of results commonly indicates that there is only a single measurement for a particular property. This handbook summarizes currently available information about U, Pu, Zr, Np, Am, La, Ce, Pr, and Nd and alloys of two or three of these elements. It contains information about phase diagrams and related information (including phases and phase transformations); heat capacity, entropy, and enthalpy; thermal expansion; and thermal conductivity and diffusivity. In addition to presenting information about materials properties, the handbook attempts to provide information about how well the property is known and how much variation exists between measurements. Although it includes some results from models, its primary focus is experimental data. The Handbook is organized in two sections: one with information about the U-Pu-Zr ternary and one with information about other elements and binary and vi ternary alloys in the U-Np-Pu-Am-La-Ce-Pr-Nd-Zr system. Within each section, information about elements is presented first, followed by information about binary alloys, then information about ternary alloys. The order in which the elements in each alloy are mentioned follows the order in the first sentence of this paragraph. Much of the information on the U-Pu-Zr system repeats information from the FCRD Transmutation Fuels Handbook 2015. Most of the other data has been published elsewhere (although scattered throughout numerous references, some quite obscure); however, some data from Idaho National Laboratory is presented here for the first time. As the FCRD programmatic mission evolves, future editions of this handbook will begin to include other advanced reactor fuel designs and compositions. Hence, the title of the handbook will transition to the Advanced Reactor Fuels Handbook.« less
Finite Element Analysis of a NASA National Transonic Facility Wind Tunnel Balance
NASA Technical Reports Server (NTRS)
Lindell, Michael C.
1996-01-01
This paper presents the results of finite element analyses and correlation studies performed on a NASA National Transonic Facility (NTF) Wind Tunnel balance. In the past NASA has relied primarily on classical hand analyses, coupled with relatively large safety factors, for predicting maximum stresses in wind tunnel balances. Now, with the significant advancements in computer technology and sophistication of general purpose analysis codes, it is more reasonable to pursue finite element analyses of these balances. The correlation studies of the present analyses show very good agreement between the analyses and data measured with strain gages and therefore the studies give higher confidence for using finite element analyses to analyze and optimize balance designs in the future.
Finite Element Analysis of a NASA National Transonic Facility Wide Tunnel Balance
NASA Technical Reports Server (NTRS)
Lindell, Michael C. (Editor)
1999-01-01
This paper presents the results of finite element analyses and correlation studies performed on a NASA National Transonic Facility (NTF) Wind Tunnel balance. In the past NASA has relied primarily on classical hand analyses, coupled with relatively large safety factors, for predicting maximum stresses in wind tunnel balances. Now, with the significant advancements in computer technology and sophistication of general purpose analysis codes, it is more reasonable to pursue finite element analyses of these balances. The correlation studies of the present analyses show very good agreement between the analyses and data measured with strain gages and therefore the studies give higher confidence for using finite element analyses to analyze and optimize balance designs in the future.
Diogenites: Cumulates from Asteroid 4 Vesta: Insights from Orthopyroxene and Spinel Chemistry
NASA Technical Reports Server (NTRS)
Papike, James J.; Bowman, L. E.; Spilde, M. N.; Fowler, G. W.; Shearer, C. K.
1996-01-01
Cumulate rocks are important planetary lithologies, but they can be difficult to interpret. Important clues to the nature of their parental melts may still be present in the interiors of cumulus phases. However, in some cases, even the cores of the cumulus grains may have been modified by postcrystallization reactions with trapped melt and other cumulus phases. We have previously studied the major-, minor-, and trace-element chemistry of orthopyroxene from a suite of diogenites and concluded that their chemical attributes can best be explained by crystallization from parental melts that were derived from a depleted mantle source that had already experienced eucrite removal. However, we and others have had difficulty explaining the great range in concentration of minor elements (Al, Ti) and trace elements (REE, Y, Zr) if all diogenites were derived from a single magmatic system. Therefore, we have investigated the chemistry of diogenitic spinels to see if they still held clues to the diogenite parental melt compositions. Although spinel is low in abundance in diogenites (<5 vol%) it still may hold clues to the maomatic and metamorphic history of these rocks.
NASA Astrophysics Data System (ADS)
Mollo, S.; Blundy, J. D.; Giacomoni, P.; Nazzari, M.; Scarlato, P.; Coltorti, M.; Langone, A.; Andronico, D.
2017-07-01
A peculiar characteristic of the paroxysmal sequence that occurred on March 16, 2013 at the New South East Crater of Mt. Etna volcano (eastern Sicily, Italy) was the eruption of siliceous crustal xenoliths representative of the sedimentary basement beneath the volcanic edifice. These xenoliths are quartzites that occur as subspherical bombs enclosed in a thin trachybasaltic lava envelope. At the quartzite-magma interface a reaction corona develops due to the interaction between the Etnean trachybasaltic magma and the partially melted quartzite. Three distinct domains are observed: (i) the trachybasaltic lava itself (Zone 1), including Al-rich clinopyroxene phenocrysts dispersed in a matrix glass, (ii) the hybrid melt (Zone 2), developing at the quartzite-magma interface and feeding the growth of newly-formed Al-poor clinopyroxenes, and (iii) the partially melted quartzite (Zone 3), producing abundant siliceous melt. These features makes it possible to quantify the effect of magma contamination by siliceous crust in terms of clinopyroxene-melt element partitioning. Major and trace element partition coefficients have been calculated using the compositions of clinopyroxene rims and glasses next to the crystal surface. Zone 1 and Zone 2 partition coefficients correspond to, respectively, the chemical analyses of Al-rich phenocrysts and matrix glasses, and the chemical analyses of newly-formed Al-poor crystals and hybrid glasses. For clinopyroxenes from both the hybrid layer and the lava flow expected relationships are observed between the partition coefficient, the valence of the element, and the ionic radius. However, with respect to Zone 1 partition coefficients, values of Zone 2 partition coefficients show a net decrease for transition metals (TE), high-field strength elements (HFSE) and rare earth elements including yttrium (REE + Y), and an increase for large ion lithophile elements (LILE). This variation is associated with coupled substitutions on the M1, M2 and T sites of the type M1(Al, Fe3 +) + TAl = M2(Mg, Fe2 +) + TSi. The different incorporation of trace elements into clinopyroxenes of hybrid origin is controlled by cation substitution reactions reflecting local charge-balance requirements. According to the lattice strain theory, simultaneous cation exchanges across the M1, M2, and T sites have profound effects on REE + Y and HFSE partitioning. Conversely, both temperature and melt composition have only a minor effect when the thermal path of magma is restricted to 70 °C and the value of non-bridging oxygens per tetrahedral cations (NBO/T) shifts moderately from 0.31 to 0.43. As a consequence, Zone 2 partition coefficients for REE + Y and HFSE diverge significantly from those derived for Zone 1, accounting for limited cation incorporation into the newly-formed clinopyroxenes at the quartzite-magma interface.
Klimasauskas, Edward P.; Miller, Marti L.; Bradley, Dwight C.; Bundtzen, Tom K.; Hudson, Travis L.
2006-01-01
The data consist of major- and minor-element concentrations for rock samples collected during 2005 by the U.S. Geological Survey. Samples were analyzed by fire assay (Au, Pd, Pt), cold vapor atomic absorption spectroscopy (Hg), and the inductively coupled plasma mass spectrometry (ICPMS) 10 and 42 element methods. For details of sample preparation and analytical techniques see USGS Open File Report 02-0223 (Analytical methods for chemical analysis of geologic and other materials, U.S. Geological Survey), available at .
NASA Technical Reports Server (NTRS)
Flynn, G. J.; Keller, L. P.; Wirick, S.; Jacobsen, C.
2004-01-01
Many anhydrous interplanetary dust particles (IDPs) are the most pristine samples of primitive solar system dust currently available for laboratory analysis. Their primitive nature is demonstrated by: 1) the high content of moderately volatile elements, indicating they have not been heated significantly since formation, 2) the absence of hydrated material, indicating they never experienced aqueous processing, 3) the presence of unequilibrated mineral assemblages, 4) the presence of large isotopic anomalies (e.g., D and 15N enrichment), in these IDPs.
NASA Astrophysics Data System (ADS)
Greenberger, Rebecca N.; Mustard, John F.; Osinski, Gordon R.; Tornabene, Livio L.; Pontefract, Alexandra J.; Marion, Cassandra L.; Flemming, Roberta L.; Wilson, Janette H.; Cloutis, Edward A.
2016-12-01
Meteorite impacts on Earth and Mars can generate hydrothermal systems that alter the primary mineralogies of rocks and provide suitable environments for microbial colonization. We investigate a calcite-marcasite-bearing vug at the 23 km diameter Haughton impact structure, Devon Island, Nunavut, Canada, using imaging spectroscopy of the outcrop in the field (0.65-1.1 μm) and samples in the laboratory (0.4-2.5 μm), point spectroscopy (0.35-2.5 μm), major element chemistry, and X-ray diffraction analyses. The mineral assemblages mapped at the outcrop include marcasite; marcasite with minor gypsum and jarosite; fibroferrite and copiapite with minor gypsum and melanterite; gypsum, Fe3+ oxides, and jarosite; and calcite, gypsum, clay, microcline, and quartz. Hyperspectral mapping of alteration phases shows spatial patterns that illuminate changes in alteration conditions and formation of specific mineral phases. Marcasite formed from the postimpact hydrothermal system under reducing conditions, while subsequent weathering oxidized the marcasite at low temperatures and water/rock ratios. The acidic fluids resulting from the oxidation collected on flat-lying portions of the outcrop, precipitating fibroferrite + copiapite. That assemblage then likely dissolved, and the changing chemistry and pH resulting from interaction with the calcite-rich host rock formed gypsum-bearing red coatings. These results have implications for understanding water-rock interactions and habitabilities at this site and on Mars.
Correlations in metal release profiles following sorption by Lemna minor.
Üçüncü Tunca, Esra; Ölmez, Tolga T; Özkan, Alper D; Altındağ, Ahmet; Tunca, Evren; Tekinay, Turgay
2016-08-02
Following the rapid uptake of contaminants in the first few hours of exposure, plants typically attempt to cope with the toxic burden by releasing part of the sorbed material back into the environment. The present study investigates the general trends in the release profiles of different metal(loid)s in the aquatic macrophyte Lemna minor and details the correlations that exist between the release of metal(loid) species. Water samples with distinct contamination profiles were taken from Nilüfer River (Bursa, Turkey), Yeniçağa Lake (Bolu, Turkey), and Beyşehir Lake (Konya, Turkey) and used for release studies; 36 samples were tested in total. Accumulation and release profiles were monitored over five days for 11 metals and a metalloid ((208)Pb, (111)Cd, (52)Cr,(53)Cr,(60)Ni,(63)Cu,(65)Cu,(75)As,(55)Mn, (137)Ba, (27)Al, (57)Fe, (66)Zn,(68)Zn) and correlation, cluster and principal component analyses were employed to determine the factors that affect the release of these elements. Release profiles of the tested metal(loid)s were largely observed to be distinct; however, strong correlations have been observed between certain metal pairs (Cr/Ni, Cr/Cu, Zn/Ni) and principal component analysis was able to separate the metal(loid)s into three well-resolved groups based on their release.
Conaway, Christopher; Thordsen, James J.; Manning, Michael A.; Cook, Paul J.; Trautz, Robert C.; Thomas, Burt; Kharaka, Yousif K.
2016-01-01
The chemical composition of formation water and associated gases from the lower Cretaceous Paluxy Formation was determined using four different sampling methods at a characterization well in the Citronelle Oil Field, Alabama, as part of the Southeast Regional Carbon Sequestration Partnership (SECARB) Phase III Anthropogenic Test, which is an integrated carbon capture and storage project. In this study, formation water and gas samples were obtained from well D-9-8 #2 at Citronelle using gas lift, electric submersible pump, U-tube, and a downhole vacuum sampler (VS) and subjected to both field and laboratory analyses. Field chemical analyses included electrical conductivity, dissolved sulfide concentration, alkalinity, and pH; laboratory analyses included major, minor and trace elements, dissolved carbon, volatile fatty acids, free and dissolved gas species. The formation water obtained from this well is a Na–Ca–Cl-type brine with a salinity of about 200,000 mg/L total dissolved solids. Differences were evident between sampling methodologies, particularly in pH, Fe and alkalinity. There was little gas in samples, and gas composition results were strongly influenced by sampling methods. The results of the comparison demonstrate the difficulty and importance of preserving volatile analytes in samples, with the VS and U-tube system performing most favorably in this aspect.
Commeau, R.F.; Reynolds, Leslie A.; Poag, C.W.
1985-01-01
The composition of agglutinated foraminiferal tests vary remarkably in response to local substrate characteristics, physiochemical properties of the water column and species- dependant selectivity of test components. We have employed a technique that combines a scanning electron microscope with an energy dispersive X-ray spectrometer system to identify major and minor elemental constituents of agglutinated foraminiferal walls. As a sample is bombarded with a beam of high energy electrons, X-rays are generated that are characteristic of the elements present. As a result, X- ray density maps can be produced for each of several elements present in the tests of agglutinated foraminifers.
Federal Register 2010, 2011, 2012, 2013, 2014
2010-11-18
... measurements as well as finite element modelling and fatigue analyses to better understand the stress... include strain measurements as well as finite element modeling and fatigue analyses to better understand... finite element modelling and fatigue analyses to better understand the stress distribution onto the frame...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Garzenne, Claude; Massara, Simone; Tetart, Philippe
2006-07-01
Accelerator Driven Systems offer the advantage, thanks to the core sub-criticality, to burn highly radioactive elements such as americium and curium in a dedicated stratum, and then to avoid polluting with these elements the main part of the nuclear fleet, which is optimized for electricity production. This paper presents firstly the ADS model implemented in the fuel cycle simulation code TIRELIRE-STRATEGIE that we developed at EDF R and D Division for nuclear power scenario studies. Then we show and comment the results of TIRELIRE-STRATEGIE calculation of a transition scenario between the current French nuclear fleet, and a fast reactor fleetmore » entirely deployed towards the end of the 21. century, consistently with the EDF prospective view, with 3 options for the minor actinides management:1) vitrified with fission products to be sent to the final disposal; 2) extracted together with plutonium from the spent fuel to be transmuted in Generation IV fast reactors; 3) eventually extracted separately from plutonium to be incinerated in a ADSs double stratum. The comparison of nuclear fuel cycle material fluxes and inventories between these options shows that ADSs are not more efficient than critical fast reactors for reducing the high level waste radio-toxicity; that minor actinides inventory and fluxes in the fuel cycle are more than twice as high in case of a double ADSs stratum than in case of minor actinides transmutation in Generation IV FBRs; and that about fourteen 400 MWth ADS are necessary to incinerate minor actinides issued from a 60 GWe Generation IV fast reactor fleet, corresponding to the current French nuclear fleet installed power. (authors)« less
Geochemistry of the Patricia Zn-Pb-Ag Deposit (paguanta, NE Chile)
NASA Astrophysics Data System (ADS)
Chinchilla Benavides, D.; Merinero Palomares, R.; Piña García, R.; Ortega Menor, L.; Lunar Hernández, R.
2013-12-01
The Patricia Zn-Pb-Ag ore deposit is located within the Paguanta mining project, situated at the northern end of the Andean Oligocene Porphyry Copper Belt of Chile. The sulfide mineralization occurs as W-E oriented veins hosted in volcanic rocks, mainly andesite (pyroclastic, ash and lavas), of Upper Cretaceous to Middle Tertiary age. The ore mineralogy (obtained by EMPA analyses) comprises in order of abundance, pyrite, sphalerite (5.5 - 10.89 wt % Fe, 9.8-19 % molar FeS and 0.52 wt % Cd), galena, arsenopyrite, chalcopyrite and Ag-bearing sulfosalts. The veins show a zoned and banded internal structure with pyrite at the edges and sphalerite in the center. The Ag occurs mostly as Ag-Cu-Sb sulfosalts, in order of abundance: series freibergite - argentotennantite -polybasite and stephanite. Other minor Ag phases such as argentite, pyrargirite and diaphorite were also identified. These Ag phases are typically associated with the base-metal sulfides. Freibergite occurs filling voids within sphalerite, chalcopyrite and at the contact between sphalerite and galena. Polybasite, stephanite, pyrargirite and argentite are mostly in close association with freibergite. In the case of diaphorite, it commonly occurs filling voids between galena crystals or as inclusions within galena. Some minor Ag-bearing sulfosalts are also identified between pyrite crystals. The alteration minerals are dominated by chlorite, illite and kaolinite. The gangue minerals consist of quartz and carbonates identified by XRD as kutnahorite. We obtained linear correlation statistically significant only for Ag, As Au, Cd, Cu, Pb, Sb and Zn and therefore we generated an enhanced scatter plot matrix of these elements. Bulk rock analyses (ICP/MS and XRF) of drill cores show that Ag is strongly and positively correlated with Pb and As, moderately with Cd, Sb, Au and Zn and weakly with Cu, while Au is moderately and positively correlated with Ag, As, Cd, Sb and Zn and weakly with Cu and Pb. These results are consistent with bulk rock analyses of selected and mineralized samples were similar correlations have been obtained. Ag positive correlations indicate that the formation of Ag-bearing minerals is mainly associated with galena, arsenopyrite and sphalerite occurrence. Au positive correlations indicate that this element occurs in close relationship with Ag-bearing minerals, arsenopyrite and sphalerite. The weak correlation between Cu and Ag and Au indicate that the formation of chalcopyrite is not related with the main stages of Ag-Au mineralization. The main conclusion of this study is that geochemical analyses along drill cores that cut mineralization confirm that the occurrence of Ag and Au in the Paguanta deposit is associated with the formation of galena, arsenopyrite and sphalerite. This study also confirm previous conclusions suggesting that the Patricia Pb-Zn-Ag ore deposit probably represents an example of epithermal mineralization of intermediate sulfidation state, with periods of lower sulfidation state during sphalerite deposition.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Johnson, Christian I.; Rich, R. Michael; Kobayashi, Chiaki
2013-03-10
We present radial velocities and chemical abundance ratios of [Fe/H], [O/Fe], [Si/Fe], and [Ca/Fe] for 264 red giant branch stars in three Galactic bulge off-axis fields located near (l, b) = (-5.5, -7), (-4, -9), and (+8.5, +9). The results are based on equivalent width and spectrum synthesis analyses of moderate resolution (R Almost-Equal-To 18,000), high signal-to-noise ratio (S/N {approx} 75-300 pixel{sup -1}) spectra obtained with the Hydra spectrographs on the Blanco 4 m and WIYN 3.5 m telescopes. The targets were selected from the blue side of the giant branch to avoid cool stars that would be strongly affectedmore » by CN and TiO; however, a comparison of the color-metallicity distribution in literature samples suggests that our selection of bluer targets should not present a significant bias against metal-rich stars. We find a full range in metallicity that spans [Fe/H] Almost-Equal-To -1.5 to +0.5, and that, in accordance with the previously observed minor-axis vertical metallicity gradient, the median [Fe/H] also declines with increasing Galactic latitude in off-axis fields. The off-axis vertical [Fe/H] gradient in the southern bulge is estimated to be {approx}0.4 dex kpc{sup -1}; however, comparison with the minor-axis data suggests that a strong radial gradient does not exist. The (+8.5, +9) field exhibits a higher than expected metallicity, with a median [Fe/H] = -0.23, that might be related to a stronger presence of the X-shaped bulge structure along that line-of-sight. This could also be the cause of an anomalous increase in the median radial velocity for intermediate metallicity stars in the (+8.5, +9) field. However, the overall radial velocity and dispersion for each field are in good agreement with recent surveys and bulge models. All fields exhibit an identical, strong decrease in velocity dispersion with increasing metallicity that is consistent with observations in similar minor-axis outer bulge fields. Additionally, the [O/Fe], [Si/Fe], and [Ca/Fe] versus [Fe/H] trends are identical among our three fields, and are in good agreement with past bulge studies. We find that stars with [Fe/H] {approx}< -0.5 are {alpha}-enhanced, and that the [{alpha}/Fe] ratios decline at higher metallicity. At [Fe/H] {approx}< 0, the {alpha}-element trends are indistinguishable from the halo and thick disk, and the variations in the behavior of individual {alpha}-elements are consistent with production in massive stars and a rapid bulge formation timescale.« less
Experimental and Analytical Studies of Solar System Chemistry
NASA Technical Reports Server (NTRS)
Burnett, Donald S.
2003-01-01
The cosmochemistry research funded by this grant resulted in the publications given in the attached Publication List. The research focused in three areas: (1) Experimental studies of trace element partitioning. (2) Studies of the minor element chemistry and O isotopic compositions of MgAlO4 spinels from Ca-Al-Rich Inclusions in carbonaceous chondrite meteorites, and (3) The abundances and chemical fractionations of Th and U in chondritic meteorites.
McInroy, Lauren B; D'Souza, Sandra A; Austin, Ashley; McCready, Lance T; Eaton, Andrew D; Shade, Leslie R; Wagaman, M Alex
2017-01-01
Background Sexual and gender minority youth are a population in peril, exemplified by their disproportionate risk of negative experiences and outcomes. Sexual and gender minority youth may be particularly active users of information and communication technologies (ICTs), and it is important to identify the potential contributions of ICTs to their resilience and well-being. Objective Our aim was to (1) investigate the use of ICTs by sexual and gender minority youth, (2) identify the ways that ICTs influence the resilience and coping of sexual and gender minority youth, focusing on promotion of well-being through self-guided support-seeking (particularly using mobile devices), (3) develop a contextually relevant theoretical conceptualization of resilience incorporating minority stress and ecological approaches, (4) generate best practices and materials that are accessible to multiple interested groups, and (5) identify whether video narratives are a viable alternative to collect qualitative responses in Web-based surveys for youth. Methods Mixed methods, cross-sectional data (N=6309) were collected via a Web-based survey from across the United States and Canada from March-July 2016. The sample was generated using a multipronged, targeted recruitment approach using Web-based strategies and consists of self-identified English-speaking sexual and gender minority youth aged 14-29 with technological literacy sufficient to complete the Web-based survey. The survey was divided into eight sections: (1) essential demographics, (2) ICT usage, (3) health and mental health, (4) coping and resilience, (5) sexual and gender minority youth identities and engagement, (6) fandom communities, (7) nonessential demographics, and (8) a video submission (optional, n=108). The option of a 3-5 minute video submission represents a new research innovation in Web-based survey research. Results Data collection is complete (N=6309), and analyses are ongoing. Proposed analyses include (1) structural equation modeling of quantitative data, (2) grounded theory analysis of qualitative data, and (3) an integrative, mixed methods analysis using a data transformation design. Theoretical and methodological triangulation of analyses integrates an interwoven pattern of results into a comprehensive picture of a phenomenon. Results will be reported in 2017 and 2018. Conclusions This research study will provide critical insights into the emerging use of ICTs by sexual and gender minority youth and identify intervention strategies to improve their well-being and reduce risks encountered by this vulnerable population. Implications for practice, research, and knowledge translation are provided. PMID:28958984
ERIC Educational Resources Information Center
Severiens, Sabine; Wolff, Rick
2008-01-01
This article examines students from ethnic minorities and majorities with regard to the relationships between their social and academic integration and their quality of learning. A total of 523 students at four universities completed a questionnaire: analyses of variance were used to examine mean differences, and structural equation modelling…
ERIC Educational Resources Information Center
Parsons, Carl
2009-01-01
The enquiries into police action in the Stephen Lawrence murder, the Macpherson report and the subsequent race relations legislation have altered the political, professional and wider social climate of debate on equality issues, including inequalities in minority ethnic exclusions. The paper analyses the meanings given to racism and institutional…
ERIC Educational Resources Information Center
Khanal, Peshal
2017-01-01
Nepal's multicultural society is hierarchical and divided along the lines of caste, ethnicity and language and its school system, including curriculum and pedagogy, is influenced greatly by the dominant language and culture. In this context, this article analyses the difficulties and struggle ethnic minority children experience as they move…
Computer Access and Computer Use for Science Performance of Racial and Linguistic Minority Students
ERIC Educational Resources Information Center
Chang, Mido; Kim, Sunha
2009-01-01
This study examined the effects of computer access and computer use on the science achievement of elementary school students, with focused attention on the effects for racial and linguistic minority students. The study used the Early Childhood Longitudinal Study (ECLS-K) database and conducted statistical analyses with proper weights and…
Correlates of Cutting Behavior among Sexual Minority Youths and Young Adults
ERIC Educational Resources Information Center
Walls, N. Eugene; Laser, Julie; Nickels, Sarah J.; Wisneski, Hope
2010-01-01
Using secondary analyses of data from a sample of 265 sexual minority youths, the authors examined correlates of cutting behavior to determine whether patterns are similar to those found in studies of self-injury with community samples of predominately heterosexual youths. The sample consisted of youths who received services at an urban social…
ERIC Educational Resources Information Center
Luke, Allan
2017-01-01
Adam Wright, Michael A. Gottfried, and Vi-Nhuan Le demonstrate empirically that minority teachers have a positive impact on the "social-emotional development" of American minority kindergarten children. Their analyses of 2010-2011 data from the Early Childhood Longitudinal Study focus on measurable effects in four social and affective…
ERIC Educational Resources Information Center
Woolf, Katherine; Haq, Inam; McManus, I. Chris; Higham, Jenny; Dacre, Jane
2008-01-01
Evidence shows that medical students from Minority Ethnic (ME) backgrounds and male medical students underperform in undergraduate examinations. Our study confirmed these findings in first year clinical (year 3) medical students, and further explored this disparity in performance. We conducted a series of meta-analyses to measure the effects of…
Biesbroek, J Matthijs; Weaver, Nick A; Hilal, Saima; Kuijf, Hugo J; Ikram, Mohammad Kamran; Xu, Xin; Tan, Boon Yeow; Venketasubramanian, Narayanaswamy; Postma, Albert; Biessels, Geert Jan; Chen, Christopher P L H
2016-01-01
Studies on the impact of small vessel disease (SVD) on cognition generally focus on white matter hyperintensity (WMH) volume. The extent to which WMH location relates to cognitive performance has received less attention, but is likely to be functionally important. We examined the relation between WMH location and cognition in a memory clinic cohort of patients with sporadic SVD. A total of 167 patients with SVD were recruited from memory clinics. Assumption-free region of interest-based analyses based on major white matter tracts and voxel-wise analyses were used to determine the association between WMH location and executive functioning, visuomotor speed and memory. Region of interest-based analyses showed that WMHs located particularly within the anterior thalamic radiation and forceps minor were inversely associated with both executive functioning and visuomotor speed, independent of total WMH volume. Memory was significantly associated with WMH volume in the forceps minor, independent of total WMH volume. An independent assumption-free voxel-wise analysis identified strategic voxels in these same tracts. Region of interest-based analyses showed that WMH volume within the anterior thalamic radiation explained 6.8% of variance in executive functioning, compared to 3.9% for total WMH volume; WMH volume within the forceps minor explained 4.6% of variance in visuomotor speed and 4.2% of variance in memory, compared to 1.8% and 1.3% respectively for total WMH volume. Our findings identify the anterior thalamic radiation and forceps minor as strategic white matter tracts in which WMHs are most strongly associated with cognitive impairment in memory clinic patients with SVD. WMH volumes in individual tracts explained more variance in cognition than total WMH burden, emphasizing the importance of lesion location when addressing the functional consequences of WMHs.
HPV infection among a population-based sample of sexual minority women from USA
Reiter, Paul L; McRee, Annie-Laurie
2017-01-01
Objectives Sexual minority women are at risk for infection with human papillomavirus (HPV); yet, relatively little is known about the prevalence of HPV infection among this population. Methods We analysed data from the 2003–2012 National Health and Nutrition Examination Survey among women aged 20–59 (n=7132). We examined two dimensions of sexual orientation (sexual identity and sexual behaviour) and used weighted logistic regression to determine how HPV infection outcomes (any HPV type, high-risk HPV type and vaccine HPV type) vary by dimension. Results Similar patterns emerged for sexual identity and sexual behaviour. In bivariate analyses, HPV infection outcomes were more common among non-heterosexual women compared with heterosexual women (any type: 49.7% vs 41.1%; high-risk type: 37.0% vs 27.9%), as well as among women who reported any same-sex partners compared with women who reported only opposite-sex partners (any type: 55.9% vs 41.0%; high-risk type: 37.7% vs 28.2%; vaccine type: 19.1% vs 14.0%) (p<0.05). When we disaggregated measures of sexual orientation into subgroups, bisexual women and women who reported partners of both sexes had greater odds of HPV infection outcomes (p<0.05 in bivariate analyses). Multivariate models attenuated several of these differences, though lesbian women and women who reported only same-sex partners had lower odds of most HPV infection outcomes in multivariate analyses (p<0.05). Conclusions HPV infection is common among sexual minority women, though estimates vary depending on how sexual orientation is operationalised. Results can help inform targeted HPV and cervical cancer prevention efforts for sexual minority women. PMID:27165699
Mereish, Ethan H.; Poteat, V. Paul
2015-01-01
Sexual minorities (e.g., lesbians, gay men, bisexual individuals) are at higher risk for mental and physical health disparities than heterosexuals, and some of these disparities relate to minority stressors such as discrimination. Yet, there is little research elucidating pathways that predict health or that promote resiliency among sexual minorities. Building on the minority stress model, the present study utilized relational cultural theory to situate sexual minority health within a relational framework. Specifically, the study tested mediators of the relationships between distal (i.e., discrimination, rejection, victimization) and proximal stressors (i.e., internalized homophobia, sexual orientation concealment) and psychological and physical distress for sexual minorities. Among 719 sexual minority adults, structural equation modeling analyses were used to test four models reflecting the mediating effects of shame, poorer relationships with a close peer and the LGBT community, and loneliness on the associations between minority stressors and psychological distress (i.e., depression and anxiety) and physical distress (i.e., distressing physical symptoms). As hypothesized, the associations between distal and proximal minority stressors and distress were mediated by shame, poorer relationships with a close peer and the LGBT community, and loneliness. Findings underscore the possible relational and interpersonal mechanisms by which sexual minority stressors lead to psychological and physical distress. PMID:26010289
NASA Astrophysics Data System (ADS)
Baziotis, Ioannis; Kimura, Jun-Ichi; Pantazidis, Avgoustinos; Klemme, Stephan; Berndt, Jasper; Asimow, Paul
2017-04-01
Santorini volcano sits ˜150 km above the Wadati-Benioff zone of the Aegean arc, where the African plate subducts northward beneath the Eurasian continent (Papazachos et al. 2000). Santorini volcano has a long history: activity started ca. 650 ka (mainly rhyolites and rhyodacites), with active pulses following ca. 550 ka (basalt to rhyodacite) and ca. 360 ka (large explosive eruptions of andesite to rhyodacite and minor basalt), culminating in the caldera-forming Bronze-age Minoan event (Druitt et al. 1999). As in many arc volcanoes, scenarios of fractional crystallization with or without mixing between felsic and mafic magmas have been proposed to explain the compositions, textures, and eruptive styles of Santorini products (e.g., Huijsmans & Barton 1989; Montazavi & Sparks 2004; Andújar et al. 2015). Here we focus on a basalt lava from the southern part of Santorini volcano (Balos cove, 36˚ 21.7'N, 25˚ 23.8'E), one of the few basaltic localities in the Aegean arc. The goals are to infer constraints on the magma chamber conditions which lead to mafic eruption at Santorini Volcano and to evaluate the slab and mantle wedge conditions via geochemical and petrological mass balance modelling. We collected and characterised 20 samples for texture (SEM), mineral chemistry (FE-EPMA) and whole-rock chemistry (XRF). The basalts contain phenocrystic olivine (Ol) and clinopyroxene (Cpx) (<600 μm diameter) in a fine groundmass (<100 μm diameter) of Ol, Cpx, plagioclase (Pl) and magnetite (Mt) with minor glass and rare xenocrystic quartz. Santorini basalts exhibit a pilotaxitic to trachytic texture defined by randomly to flow-oriented tabular Pl, respectively. The predominant minerals are calcic Pl (core An78-85 and rim An60-76; 45-50 vol.%), Cpx (En36-48Wo41-44Fs11-21; 10-15 vol.%) and Ol (Fo74-88; 10-12 vol.%). Idiomorphic to subidiomorphic Mt (<10μm diameter) with variable TiO2 contents (1.9-16.5 wt%) is a minor constituent (˜1-2 vol.%) in the less mafic samples. Observed mineralogy and major element chemistry suggest fractionation in a shallow magma chamber. Using the major element chemistry and PRIMACALC2 (Kimura & Ariskin 2014) back-calculator, inferred crystallization conditions are P=0.02 GPa, oxidized (fO2=QFM+2), and ˜1 wt% H2O in the primary basalt. The source mantle conditions are estimated at P=2.1 GPa, T=1350˚ C, and degree of melting F=8%. We also used trace elements to estimate the incompatible element budget of the primary basalt using the forward trace-element mass-balance model of ARC BASALT SIMULATOR ver.4 (Kimura et al. 2014). Preliminary results suggest that the slab flux was derived from ˜150 km depth, and fluxed mantle melting occurred at P=2.3 GPa, T=1380˚ C, F=8%. The estimated slab depth is consistent with the seismic observations and mantle conditions are consistent with the PRIMACALC2 major element modelling. Our intent is to extend our analytical data with precise trace element and isotope analyses in order to reveal more detailed source conditions and richer information about processes from the slab through the mantle and up to the shallow magma chamber. References Andújar, J. et al. (2015). JPET, 56 (4), 765-794. Druitt, et al. (1999). Geological Society Memoir, 19. Huijsmans, J. P., & Barton, M. (1989). JPET, 30(3), 583-625. Kimura, J. I., & Ariskin, A. A. (2014). G3, 15, 1494-1514. Kimura, J. I. et al. (2014). G3, 15, 691-739. Mortazavi, M., & Sparks, R. S. J. (2004). Con Min Pet, 146(4), 397-413. Papazachos, et al. (2000). Tectonophysics, 319(4), 275-300.
Quantitative Effects of P Elements on Hybrid Dysgenesis in Drosophila Melanogaster
Rasmusson, K. E.; Simmons, M. J.; Raymond, J. D.; McLarnon, C. F.
1990-01-01
Genetic analyses involving chromosomes from seven inbred lines derived from a single M' strain were used to study the quantitative relationships between the incidence and severity of P-M hybrid dysgenesis and the number of genomic P elements. In four separate analyses, the mutability of sn(w), a P element-insertion mutation of the X-linked singed locus, was found to be inversely related to the number of autosomal P elements. Since sn(w) mutability is caused by the action of the P transposase, this finding supports the hypothesis that genomic P elements titrate the transposase present within a cell. Other analyses demonstrated that autosomal transmission ratios were distorted by P element action. In these analyses, the amount of distortion against an autosome increased more or less linearly with the number of P elements carried by the autosome. Additional analyses showed that the magnitude of this distortion was reduced when a second P element-containing autosome was present in the genome. This reduction could adequately be explained by transposase titration; there was no evidence that it was due to repressor molecules binding to P elements and inhibiting their movement. The influence of genomic P elements on the incidence of gonadal dysgenesis was also investigated. Although no simple relationship between the number of P elements and the incidence of the trait could be discerned, it was clear that even a small number of elements could increase the incidence markedly. The failure to find a quantitative relationship between P element number and the incidence of gonadal dysgenesis probably reflects the complex etiology of this trait. PMID:2155853
Voskarides, Konstantinos; Mazières, Stéphane; Hadjipanagi, Despina; Di Cristofaro, Julie; Ignatiou, Anastasia; Stefanou, Charalambos; King, Roy J; Underhill, Peter A; Chiaroni, Jacques; Deltas, Constantinos
2016-01-01
The archeological record indicates that the permanent settlement of Cyprus began with pioneering agriculturalists circa 11,000 years before present, (ca. 11,000 y BP). Subsequent colonization events followed, some recognized regionally. Here, we assess the Y-chromosome structure of Cyprus in context to regional populations and correlate it to phases of prehistoric colonization. Analysis of haplotypes from 574 samples showed that island-wide substructure was barely significant in a spatial analysis of molecular variance (SAMOVA). However, analyses of molecular variance (AMOVA) of haplogroups using 92 binary markers genotyped in 629 Cypriots revealed that the proportion of variance among the districts was irregularly distributed. Principal component analysis (PCA) revealed potential genetic associations of Greek-Cypriots with neighbor populations. Contrasting haplogroups in the PCA were used as surrogates of parental populations. Admixture analyses suggested that the majority of G2a-P15 and R1b-M269 components were contributed by Anatolia and Levant sources, respectively, while Greece Balkans supplied the majority of E-V13 and J2a-M67. Haplotype-based expansion times were at historical levels suggestive of recent demography. Analyses of Cypriot haplogroup data are consistent with two stages of prehistoric settlement. E-V13 and E-M34 are widespread, and PCA suggests sourcing them to the Balkans and Levant/Anatolia, respectively. The persistent pre-Greek component is represented by elements of G2-U5(xL30) haplogroups: U5*, PF3147, and L293. J2b-M205 may contribute also to the pre-Greek strata. The majority of R1b-Z2105 lineages occur in both the westernmost and easternmost districts. Distinctively, sub-haplogroup R1b- M589 occurs only in the east. The absence of R1b- M589 lineages in Crete and the Balkans and the presence in Asia Minor are compatible with Late Bronze Age influences from Anatolia rather than from Mycenaean Greeks.
A computer graphics program for general finite element analyses
NASA Technical Reports Server (NTRS)
Thornton, E. A.; Sawyer, L. M.
1978-01-01
Documentation for a computer graphics program for displays from general finite element analyses is presented. A general description of display options and detailed user instructions are given. Several plots made in structural, thermal and fluid finite element analyses are included to illustrate program options. Sample data files are given to illustrate use of the program.
Field, Frank R; Wallington, Timothy J; Everson, Mark; Kirchain, Randolph E
2017-12-19
A comprehensive component-level assessment of several strategic and minor metals (SaMMs), including copper, manganese, magnesium, nickel, tin, niobium, light rare earth elements (LREEs; lanthanum, cerium, praseodymium, neodymium, promethium, and samarium), cobalt, silver, tungsten, heavy rare earth elements (yttrium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, and lutetium), and gold, use in the 2013 model year Ford Fiesta, Focus, Fusion, and F-150 is presented. Representative material contents in cars and light-duty trucks are estimated using comprehensive, component-level data reported by suppliers. Statistical methods are used to accommodate possible errors within the database and provide estimate bounds. Results indicate that there is a high degree of variability in SaMM use and that SaMMs are concentrated in electrical, drivetrain, and suspension subsystems. Results suggest that trucks contain greater amounts of aluminum, nickel, niobium, and silver and significantly greater amounts of magnesium, manganese, gold, and LREEs. We find tin and tungsten use in automobiles to be 3-5 times higher than reported by previous studies which have focused on automotive electronics. Automotive use of strategic and minor metals is substantial, with 2013 vehicle production in the United States, Canada, EU15, and Japan alone accounting for approximately 20% of global production of Mg and Ta and approximately 5% of Al, Cu, and Sn. The data and analysis provide researchers, recyclers, and decision-makers additional insight into the vehicle content of strategic and minor metals of current interest.
Ridley, W.I.; Perfit, M.R.; Josnasson, I.R.; Smith, M.F.
1994-01-01
The Galapagos Fossil Hydrothermal Field is composed of altered oceanic crust and extinct hydrothermal vents within the eastern Galapagos Rift between 85??49???W and 85??55???W. The discharge zone of the hydrothermal system is revealed along scarps, thus providing an opportunity to examine the uppermost mineralized, and highly altered interior parts of the crust. Altered rocks collected in situ by the submersible ALVIN show complex concentric alteration zones. Microsamples of individual zones have been analysed for major/minor, trace elements, and strontium isotopes in order to describe the complex compositional details of the hydrothermal alteration. Interlayered chlorite-smectite and chlorite with disequilibrium compositions dominate the secondary mineralogy as replacement phases of primary glass and acicular pyroxene. Phenocrysts and matrix grains of plagioclase are unaffected during alteration. Using a modification of the Gresens' equation we demonstrate that the trivalent rare earth elements (REEs) are relatively immobile, and calculate degrees of enrichment and depletion in other elements. Strontium isotopic ratios increase as Sr concentrations decrease from least-altered cores to most-altered rims and cross-cutting veins in individual samples, and can be modeled by open system behaviour under low fluid-rock ratio (< 10) conditions following a period of lower-temperature weathering of volcanics within the rift zone. The complex patterns of element enrichment and depletion and strontium isotope variations indicate mixing between pristine seawater and ascending hot fluids to produce a compositional spectrum of fluids. The precipitation of base-metal sulfides beneath the seafloor is probably a result of fluid mixing and cooling. If, as suggested here, the discharge zone alteration occurred under relatively low fluid-rock ratios, then this shallow region must play an important role in determining the exit composition of vent fluids in marine hydrothermal systems. ?? 1994.
A Geochemical Study of Postshield Volcanism and the Generation of Trachyte on West Maui, HI
NASA Astrophysics Data System (ADS)
Trenkler, M. L.; Cousens, B.
2016-12-01
The West Maui Volcano provides a complete evolutionary history of a fully developed Hawaiian volcano described by three main phases: (1) the tholeiitic shield-building stage of the Wailuku Basalts; (2) the postshield alkalic stage Honolua Volcanics; and (3) the rejuvenated stage Lahaina Volcanics of silica-undersaturated rocks. On West Maui, the postshield Honolua Volcanics erupted highly differentiated rocks (benmoreite to trachyte), with little to no intermediate alkalic rocks, upon cessation of tholeiitic shield building. Utilizing K-Ar dated samples, we present 35 new major and trace element analyses of shield, postshield, and rejuvenated stage lavas on West Maui in an attempt to identify the mechanisms present during evolution from basalt to trachyte over a defined temporal and spatial range. Wailuku basalts are dominated by olivine fractionation, whereas decreasing Sc and CaO/Al2O3 with increasing degree of differentiation indicate Honolua benmoreites and trachytes heavily fractionated clinopyroxene. Major element trends are consistent with crystallization of titano-magnetite, potassium feldspar, and minor apatite. Trace element patterns of the Honolua Volcanics are uniform with strong enrichments in LILE and the LREEs indicating fractionation and lower degrees of partial melting compared to Wailuku basalts. The HREEs are enriched relative to shield basalts with Gd/Yb values of 2.0-2.8 as a result of high degrees of fractionation and the presence of crystalizing apatite. Major and trace element trends follow the evolution of the postshield Hawi Volcanics of Kohala, where alkalic basalts differentiate up to trachyte. Compared to shield lavas, the Honolua Volcanics represent a drastic decrease in magma supply rates, infrequent eruptions, and magma residence times long enough to produce highly differentiated magmas with no significant mafic magma input.
Yaguchi, Toshie; Konno, Mitsuru; Kamino, Takeo; Watanabe, Masashi
2008-11-01
A technique for preparation of a pillar-shaped specimen and its multidirectional observation using a combination of a scanning transmission electron microscope (STEM) and a focused ion beam (FIB) instrument has been developed. The system employs an FIB/STEM compatible holder with a specially designed tilt mechanism, which allows the specimen to be tilted through 360 degrees [T. Yaguchi, M. Konno, T. Kamino, T. Hashimoto, T. Ohnishi, K. Umemura, K. Asayama, Microsc. Microanal. 9 (Suppl. 2) (2003) 118; T. Yaguchi, M. Konno, T. Kamino, T. Hashimoto, T. Ohnishi, M. Watanabe, Microsc. Microanal. 10 (Suppl. 2) (2004) 1030]. This technique was applied to obtain the three-dimensional (3D) elemental distributions around a contact plug of a Si device used in a 90-nm technology. A specimen containing only one contact plug was prepared in the shape of a pillar with a diameter of 200nm and a length of 5mum. Elemental maps were obtained from the pillar specimen using a 200-kV cold-field emission gun (FEG) STEM model HD-2300C equipped with the EDAX genesis X-ray energy-dispersive spectrometry (XEDS) system through a spectrum imaging technique. In this study, elemental distributions of minor elements with weak signals were enhanced by applying principal component analysis (PCA), which is a superior technique to extract weak signals from a large dataset. The distributions of elements, especially the metallization component Ti and minor dopant As in this particular device, were successfully extracted by PCA. Finally, the 3D elemental distributions around the contact plug could be visualized by reconstruction from the tilt series of maps.
Das-Munshi, Jayati; Bhugra, Dinesh; Crawford, Mike J
2018-04-18
Ethnic minority service users with schizophrenia and schizoaffective disorders may experience inequalities in care. There have been no recent studies assessing access to evidence-based treatments for psychosis amongst the main ethnic minority groups in the UK. Data from nationally representative surveys from England and Wales, for 10,512 people with a clinical diagnosis of schizophrenia or schizoaffective disorders, were used for analyses. Multi-level multivariable logistic regression analyses were used to assess ethnic minority inequalities in access to pharmacological treatments, psychological interventions, shared decision making and care planning, taking into account a range of potential confounders. Compared with white service users, black service users were more likely prescribed depot/injectable antipsychotics (odds ratio 1.56 (95% confidence interval 1.33-1.84)). Black service users with treatment resistance were less likely to be prescribed clozapine (odds ratio 0.56 (95% confidence interval 0.39-0.79)). All ethnic minority service users, except those of mixed ethnicity, were less likely to be offered cognitive behavioural therapy, compared to white service users. Black service users were less likely to have been offered family therapy, and Asian service users were less likely to have received copies of care plans (odds ratio 0.50 (95% confidence interval 0.33-0.76)), compared to white service users. There were no clinician-reported differences in shared decision making across each of the ethnic minority groups. Relative to white service users, ethnic minority service users with psychosis were generally less likely to be offered a range of evidence-based treatments for psychosis, which included pharmacological and psychological interventions as well as involvement in care planning.
Weinberger, Andrea H.; Pilver, Corey E.; Desai, Rani A.; Mazure, Carolyn M.; McKee, Sherry A.
2012-01-01
BACKGROUND Although data clearly link major depression and smoking, little is known about the association between dysthymia and minor depression and smoking behavior. The current study examined changes in smoking over three years for current and former smokers with and without dysthymia and minor depression. METHODS Participants who were current or former daily cigarette smokers at Wave 1 of the National Epidemiologic Survey on Alcohol and Related Conditions and completed the Wave 2 assessment were included in these analyses (n=11,973; 46% female). Analyses examined the main and gender-specific effects of current dysthymia, lifetime dysthymia, and minor depression (a single diagnostic category that denoted current and or lifetime prevalence) on continued smoking for Wave 1 current daily smokers and continued abstinence for Wave 1 former daily smokers. RESULTS Wave 1 current daily smokers with current dysthymia (OR=2.13, 95% CI=1.23, 3.70) or minor depression (OR=1.53, 95% CI=1.07, 2.18) were more likely than smokers without the respective diagnosis to report continued smoking at Wave 2. Wave 1 former daily smokers with current dysthymia (OR=0.44, 95% CI=0.20, 0.96) and lifetime dysthymia (OR=0.37, 95% CI=0.15, 0.91) were less likely than those without the diagnosis to remain abstinent from smoking at Wave 2. The gender-by-diagnosis interactions were not significant, suggesting that the impact of dysthymia and minor depression on smoking behavior is similar among men and women. CONCLUSIONS Current dysthymia and minor depression are associated with a greater likelihood of continued smoking; current and lifetime dysthymia are associated with a decreased likelihood of continued smoking abstinence. PMID:22809897
Weinberger, Andrea H; Pilver, Corey E; Desai, Rani A; Mazure, Carolyn M; McKee, Sherry A
2013-01-01
Although data clearly link major depression and smoking, little is known about the association between dysthymia and minor depression and smoking behavior. The current study examined changes in smoking over 3 years for current and former smokers with and without dysthymia and minor depression. Participants who were current or former daily cigarette smokers at Wave 1 of the National Epidemiologic Survey on Alcohol and Related Conditions and completed the Wave 2 assessment were included in these analyses (n=11,973; 46% female). Analyses examined the main and gender-specific effects of current dysthymia, lifetime dysthymia, and minor depression (a single diagnostic category that denoted current and/or lifetime prevalence) on continued smoking for Wave 1 current daily smokers and continued abstinence for Wave 1 former daily smokers. Wave 1 current daily smokers with current dysthymia (OR=2.13, 95% CI=1.23, 3.70) or minor depression (OR=1.53, 95% CI=1.07, 2.18) were more likely than smokers without the respective diagnosis to report continued smoking at Wave 2. Wave 1 former daily smokers with current dysthymia (OR=0.44, 95% CI=0.20, 0.96) and lifetime dysthymia (OR=0.37, 95% CI=0.15, 0.91) were less likely than those without the diagnosis to remain abstinent from smoking at Wave 2. The gender-by-diagnosis interactions were not significant, suggesting that the impact of dysthymia and minor depression on smoking behavior is similar among men and women. Current dysthymia and minor depression are associated with a greater likelihood of continued smoking; current and lifetime dysthymia are associated with a decreased likelihood of continued smoking abstinence. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Li, Rong; Jones, Brian
2014-12-01
On Grand Cayman, the Pleistocene Ironshore Formation consists of six unconformity-bounded units of limestones that have been partially or completely altered to calcite by post-depositional meteoric diagenesis. In order to examine the diagenetic history from the perspective of geochemical elements, the concentrations of minor element (Sr, Na, Mg), trace elements (Ba, Fe, Mn, Al, Si), and rare-earth elements (REE) and yttrium (Y) were determined for 105 corals and 84 matrices collected from the Rogers Wreck Point (RWP), Western Onshore area (WO), and offshore George Town (GT) areas. With the transformation of aragonite to calcite, the Sr, Na, and Ba values decreased, but Mg increased, which are indicative of diagenetic alteration in an open water system. Due to intrinsic "vital effects" and the extrinsic diagenetic environment, the variations of Sr, Na, Ba, and Mg concentrations between Acropora and Montastrea from the GT area are different to those of their counterparts from RWP and WO. The signatures of Sr, Na, Ba, and Mg are in good agreement with the diagenetic history as determined from petrographic and stable isotopic criteria. The REE + Y (REY) concentrations (ΣREY) are higher in the matrices (0.2-6.9 ppm, average 2.6 ppm) than in the associated corals (0.1-5.4 ppm, average 0.6 ppm). Shale-normalized REY patterns of the Pleistocene Ironshore Formation are similar to those of oxygenated seawater, which are characterized by (1) light REE depletion relative to heavy REE (average DySN/SmSN = 1.7, n = 35), (2) positive La anomalies (average Pr/Pr* = 1.17, n = 53), and (3) negative Ce anomalies (average Ce/Ce* = 0.49, n = 53). The preserved seawater-like REY distribution pattern, the lack of correlation between ΣREY and mineralogy, and the lack of correlation between ΣREY and diagenesis-sensitive stable oxygen isotope (δ18O) indicate that meteoric diagenesis did not have a major impact on the REY distribution patterns. The matrices and corals in the GT area, compared to their counterparts from RWP and WO, have relatively less depleted LREE and lower Y in REY distribution pattern, suggesting contamination by minor amounts of detrital sediments. This is supported by the fact that limestones from the GT area contain abnormally high contents of detrital elements (Al, Si). The variations in ΣREY in carbonate rocks from locality to locality probably reflect variations that existed in the local depositional environments where these deposits originally formed.
Apollo 16 Evolved Lithology Sodic Ferrogabbro
NASA Technical Reports Server (NTRS)
Zeigler, Ryan; Jolliff, B. L.; Korotev, R. L.
2014-01-01
Evolved lunar igneous lithologies, often referred to as the alkali suite, are a minor but important component of the lunar crust. These evolved samples are incompatible-element rich samples, and are, not surprisingly, most common in the Apollo sites in (or near) the incompatible-element rich region of the Moon known as the Procellarum KREEP Terrane (PKT). The most commonly occurring lithologies are granites (A12, A14, A15, A17), monzogabbro (A14, A15), alkali anorthosites (A12, A14), and KREEP basalts (A15, A17). The Feldspathic Highlands Terrane is not entirely devoid of evolved lithologies, and rare clasts of alkali gabbronorite and sodic ferrogabbro (SFG) have been identified in Apollo 16 station 11 breccias 67915 and 67016. Curiously, nearly all pristine evolved lithologies have been found as small clasts or soil particles, exceptions being KREEP basalts 15382/6 and granitic sample 12013 (which is itself a breccia). Here we reexamine the petrography and geochemistry of two SFG-like particles found in a survey of Apollo 16 2-4 mm particles from the Cayley Plains 62283,7-15 and 62243,10-3 (hereafter 7-15 and 10-3 respectively). We will compare these to previously reported SFG samples, including recent analyses on the type specimen of SFG from lunar breccia 67915.
Randich, Erik; Grant, Patrick M
2006-07-01
The bullet evidence in the JFK assassination investigation was reexamined from metallurgical and statistical standpoints. The questioned specimens are comprised of soft lead, possibly from full-metal-jacketed Mannlicher-Carcano (MC), 6.5-mm ammunition. During lead refining, contaminant elements are removed to specified levels for a desired alloy or composition. Microsegregation of trace and minor elements during lead casting and processing can account for the experimental variabilities measured in various evidentiary and comparison samples by laboratory analysts. Thus, elevated concentrations of antimony and copper at crystallographic grain boundaries, the widely varying sizes of grains in MC bullet lead, and the 5-60 mg bullet samples analyzed for assassination intelligence effectively resulted in operational sampling error for the analyses. This deficiency was not considered in the original data interpretation and resulted in an invalid conclusion in favor of the single-bullet theory of the assassination. Alternate statistical calculations, based on the historic analytical data, incorporating weighted averaging and propagation of experimental uncertainties also considerably weaken support for the single-bullet theory. In effect, this assessment of the material composition of the lead specimens from the assassination concludes that the extant evidence is consistent with any number between two and five rounds fired in Dealey Plaza during the shooting.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Randich, E; Grant, P M
2006-08-29
The bullet evidence in the JFK assassination investigation was reexamined from metallurgical and statistical standpoints. The questioned specimens are comprised of soft lead, possibly from full-metal-jacketed Mannlicher-Carcano, 6.5-mm ammunition. During lead refining, contaminant elements are removed to specified levels for a desired alloy or composition. Microsegregation of trace and minor elements during lead casting and processing can account for the experimental variabilities measured in various evidentiary and comparison samples by laboratory analysts. Thus, elevated concentrations of antimony and copper at crystallographic grain boundaries, the widely varying sizes of grains in Mannlicher-Carcano bullet lead, and the 5-60 mg bullet samples analyzedmore » for assassination intelligence effectively resulted in operational sampling error for the analyses. This deficiency was not considered in the original data interpretation and resulted in an invalid conclusion in favor of the single-bullet theory of the assassination. Alternate statistical calculations, based on the historic analytical data, incorporating weighted averaging and propagation of experimental uncertainties also considerably weaken support for the single-bullet theory. In effect, this assessment of the material composition of the lead specimens from the assassination concludes that the extant evidence is consistent with any number between two and five rounds fired in Dealey Plaza during the shooting.« less
Minor elements in lunar olivine as a petrologic indicator
NASA Technical Reports Server (NTRS)
Steele, I. M.; Smith, J. V.
1975-01-01
Accurate electron microprobe analyses (approximately 50 ppm) were made for Al, Ca, Ti, Cr, Mn, and Ni in Mg-rich olivines which may derive from early lunar crust or deeper environments. Low-Ca contents consistently occur only in olivines from dunitic and troctolitic breccia: spinel troctolite and other rock types have high-Ca olivines suggesting derivation by near-surface processes. Rock 15445 has olivine with distinctly low CaO (approximately 0.01 wt.%). Chromium ranges to higher values (max.0.2 oxide wt.%) than for terrestrial harzburgites and lherzolites but is similar to the range in terrestrial komatiites. Divalent chromium may be indicated over trivalent Cr because olivines lack sufficient other elements for charge balance of the latter. NiO values in lunar specimens range from 0.00 to 0.07 wt.% and a weak anticorrelation with Cr2O3 suggests an oxidation state effect. Al2O3 values are mostly below 0.04-wt.% and show no obvious correlation with fragment type. TiO2 values lie below 0.13-wt.% and seem to correlate best with crystallization rate and plagioclase content of the host rock. High values of Al2O3 and TiO2 reported by other workers have not been confirmed, and are probably wrong.
Luppens, James A.; Janke, Louis G.; McCord, Jamey D.; Bullock, John H.; Brazeau, Lisa; Affronter, Ronald H.
2007-01-01
A performance audit of the U.S. Geological Survey (USGS), Energy Resource Program (ERP) Inorganic Geochemistry Laboratory (IGL) was conducted between August, 2003 and October, 2005. The goals were to ensure that a high level of analytical performance was maintained and identify any areas that could be enhanced. The audit was subdivided into three phases. Phase 1 was a preliminary assessment of current performance based on recent performance on CANSPEX samples. IGL performance was also compared to laboratories world-wide with similar scope. Phase 2 consisted of the implementation of the recommended changes made in Phase 1. Phase 3 of the audit consisted of a reassessment effort to evaluate the effectiveness of the recommendations made in the Phase 1 and an on-site audit of the laboratory facilities. Phases 1 and 3 required summary reports that are included in Appendices A and B of this report. The audit found that the IGL was one of the top two laboratories compared for trace element analyses. Several recommendations to enhance performance on major and minor elemental parameters were made and implemented. Demonstrated performance improvements as a result of the recommended changes were documented. Several initiatives to sustain the performance improvements gained from the audit have been implemented.
Margins for Benign Salivary Gland Neoplasms of the Head and Neck.
Carlson, Eric R; McCoy, James Michael
2017-08-01
The proper ablation of any neoplasm of the head and neck requires the inclusion of linear and anatomic barrier margins surrounding the neoplasm. Extirpative surgery of the major and minor salivary glands is certainly no exception to this surgical principle. To this end, the selection and execution of the most appropriate ablative surgical procedure for a major or minor benign salivary gland neoplasm is an essential exercise in oral and maxillofacial surgery. Of equal importance is the intraoperative identification and preservation of the pseudocapsule surrounding the benign neoplasm. This article reviews these important elements specifically related to ablative surgery of benign neoplasms of the parotid, submandibular and minor salivary glands with strict attention to observed nomenclature. Copyright © 2017 Elsevier Inc. All rights reserved.
A Black Theological Response to Race-Based Medicine: Reconciliation in Minority Communities.
Johnson, Kirk A
2017-06-01
The harm race-based medicine inflicts on minority bodies through race-based experimentation and the false solutions a race-based drug ensues within minority communities provokes concern. Such areas analyze the minority patient in a physical proxy. Though the mind and body are important entities, we cannot forget about the spirit. Healing is not just a physical practice; it includes spiritual practice. Efficient medicine includes the holistic elements of the mind, body, and spirit. Therefore, the spiritual discipline of black theology can be used as a tool to mend the harms of race-based medicine. It can be an avenue of research to further particular concerns for justice in medical care . Such theology contributes to the discussion of race-based medicine indicating the need for the voice, participation, and interdependence of minorities. Black theology can be used as a tool of healing and empowerment for health equity and awareness by exploring black theology's response to race-based medicine, analyzing race in biblical literature, using biblical literature as a tool for minority patient empowerment, building on past and current black church health advocacy with personal leadership in health advocacy.
Federal Register 2010, 2011, 2012, 2013, 2014
2010-07-27
... closed to new entrants. These instructions parallel the benefit-accrual-freeze instructions. Make minor... its premium accounting system to handle the new data element. The collection of information under the...
Shallow ground-water conditions, Tom Green County, Texas
Lee, J.N.
1986-01-01
Pollution from oil-field activities may affect the quality of water in some isolated wells and in some areas in the county. No historical records are available for determining any changes in pesticides, minor elements, or bacteria.
Hajnal, András; Csábi, Györgyi; Herold, Róbert; Jeges, Sára; Halmai, Tamás; Trixler, Dániel; Simon, Maria; Tóth, Ákos Levente; Tényi, Tamás
2016-03-30
Minor physical anomalies are external markers of abnormal brain development,so the more common appearance of these signs among the relatives of schizophrenia patients can confirm minor physical anomalies as intermediate phenotypes. The aim of the present study was to investigate the rate and topological profile of minor physical anomalies in the first-degree unaffected relatives of patients with schizophrenia compared to matched normal control subjects. Using a list of 57 minor physical anomalies (the Méhes Scale), 20 relatives of patients with the diagnosis of schizophrenia and as a comparison 20 matched normal control subjects were examined. Minor physical anomalies were more common in the head and mouth regions among the relatives of schizophrenia patients compared to normal controls. By the differentiation of minor malformations and phenogenetic variants, we have found that only phenogenetic variants were more common in the relatives of schizophrenia patients compared to the control group, however individual analyses showed, that one minor malformation (flat forehead) was more prevalent in the relative group. The results can promote the concept, that minor physical anomalies can be endophenotypic markers of the illness. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
Elements of well-being affected by criminalizing the drug user.
Iguchi, Martin Y.; London, Jennifer A.; Forge, Nell Griffith; Hickman, Laura; Fain, Terry; Riehman, Kara
2002-01-01
OBJECTIVE: The authors examine the possible adverse consequences of incarceration on drug offenders, their families, and their communities. OBSERVATIONS: State and federal policies on drug felons may affect eight elements of personal and community well-being: children and families, access to health benefits, access to housing benefits, access to assistance for higher education, immigration status, employment, eligibility to vote, and drug use or recidivism. CONCLUSIONS: Minorities have a high chance of felony conviction and an increasing lack of access to resources, suggesting that patterns of drug conviction and health disparities may be mutually reinforcing. Large numbers of people sent to prison for drug offenses are now completing their terms and reentering communities. Their reentry will disproportionately affect minority communities. Without resources (education, job opportunities, insurance, health care, housing, and the right to vote) drug abusers face a higher risk of recidivism and increase the burden on their communities. PMID:12435838
FIP effect for minor heavy solar wind ions as seen with SOHO/CELIAS/MTOF
DOE Office of Scientific and Technical Information (OSTI.GOV)
Heidrich-Meisner, Verena, E-mail: heidrich@physik.uni-kiel.de; Berger, Lars; Wimmer-Schweingruber, Robert F.
A recent paper [Shearer et al., 2014] reported that during solar maximum Ne showed a surprisingly low abundance. This leads to the question whether other elements show the same behavior. The good mass resolution of Mass-Time-Of-Flight (MTOF) as part of the Charge ELement and Isotope Analysis System (CELIAS) on the Solar Helioshperic Observatory (SOHO) allows to investigate the composition of heavy minor elements in different types of solar wind. We restrict this study to slow solar wind, where the characterisation of slow solar wind is taken from Xu and Borovsky, 2014. This classification scheme requires magnet field information. Since SOHOmore » does not carry a magnetometer, we use the Magnetometer (MAG) of the Advanced Composition Explorer (ACE) instead. The Solar Wind Ion Composition Spectrometer (ACE/SWICS) also provides composition data for cross-calibration and charge-state distributions as input for the transmission function of MTOF whenever the two spacecraft can be expected to observe the same type of wind. We illustrate the MTOF’s capability to determine the solar wind abundance compared to the photospheric abundance (called the FIP ratio in the following) for rare elements like Ti or Cr on long-time scales as a proof of concept for our analysis. And in this brief study, measurements with both ACE/SWICS indicate that the observed elements exhibit a (weak) dependence on the solar cycle, whereas the MTOF measurements are inconclusive.« less
Study of marbles from Middle Atlas (Morocco): elemental, mineralogical and structural analysis
NASA Astrophysics Data System (ADS)
Khrissi, S.; Bejjit, L.; Haddad, M.; Falguères, C.; Ait Lyazidi, S.; El Amraoui, M.
2018-05-01
A series of marbles sampled from the region of Middle Atlas (Morocco), are characterized by different complementary spectroscopic techniques. X-Ray fluorescence is used to determine elemental composition of rock while X-Ray diffraction and the Raman spectroscopy are used to determine major crystalline phases (calcite and dolomite) and minor ones (quartz).The samples display typical EPR spectra of Mn2+ in calcite and reveal the presence of Fe3+ ions.
Tavallali, Azar G; Kabir, Zarina Nahar; Jirwe, Maria
2014-06-01
Sweden has a population of a little more than 9.4 million. The rapid growth of immigration in Sweden has resulted in an increased number of minority ethnic patients and minority ethnic nurses in the Swedish healthcare system. This also applies to paediatric care. The purpose of this study was to explore how parents with ethnic Swedish backgrounds experience minority ethnic nurses' cultural competence and the care the nurses provide in a Swedish paediatric care context. This exploratory qualitative study is of 14 parents with an ethnic Swedish background whose child was in a ward at a children's hospital in Stockholm County Council. Data were collected using semi-structured interviews to identify parents' perceptions and experiences of minority ethnic nurses' cultural competence. The interviews were analysed by qualitative content analysis. The analyses of the interviews led to four main categories: influence of nurses' ethnicity; significance of cross-cultural communication; cross-cultural skills; and the importance of nursing education. Nurses' ethnicity did not have much impact on parents' satisfaction with their child's care. The parents attached importance to nurses' language skills and to their adaptation and awareness of Swedish culture. They also attached weight to nurses' professional knowledge and personal attributes. The role of nursing education to increase nurses' cultural awareness was highlighted too. © 2013 Nordic College of Caring Science.
ERIC Educational Resources Information Center
Lonigan, Christopher J.; Farver, JoAnn M.; Nakamoto, Jonathan; Eppe, Stefanie
2013-01-01
This study utilized latent growth-curve analyses to determine if the early literacy skills of children who were Spanish-speaking language-minority (LM) followed a similar quantitative growth profile over a preschool year as that of a group of children from a comparable socioeconomic (SES) background but who were not LM. Participants, who ranged in…
Teaching Poor Ethnic Minority Students: A Critical Realist Interpretation of Disempowerment
ERIC Educational Resources Information Center
Stylianou, Areti; Scott, David
2018-01-01
This article aims to supplement the literature on the role of school context with regards to the disempowerment of teachers in their work with poor ethnic minority students. We use a critical realist framework to analyse the empirical data collected for an in-depth school case study and we suggest the existence of real, interrelated, emergent and…
ERIC Educational Resources Information Center
Woo, Hongryun; Bang, Na Mi; Cauley, Bridget; Choi, Namok
2017-01-01
This meta-analysis of five studies examined the effect of school-based intervention programs on psychosocial well-being of gifted racial/ethnic minority students in K-12 school settings. Analyses determined the overall effect sizes for various intervention programs and compared the effect sizes for subgroups by grade (i.e., elementary vs.…
Greenfield, Brenna L; Roos, Corey; Hagler, Kylee J; Stein, Elena; Bowen, Sarah; Witkiewitz, Katie A
2018-06-01
Mindfulness-based relapse prevention has shown promise as a treatment for substance use disorder but its efficacy according to racial/ethnic minority status and group composition is unknown. This is a secondary analysis of existing data (Bowen et al., 2014) testing individual race/ethnicity and racial/ethnic group composition as moderators of mindfulness-based relapse prevention (MBRP). Participants (N = 191; 29% female; 47% racial/ethnic minority; mean age = 39) with substance use disorder were randomized to MBRP or relapse prevention (RP). Outcomes were heavy drinking days (HDD) and drug use days (DUD) 12 months after treatment completion. Negative binominal regression models were conducted. Analyses accounted for drug of choice. Individual race/ethnicity was a significant moderator of substance use outcomes. White participants had lower HDD in MBRP than RP (IRR = 0, 95% CI: 0,0), whereas for minority participants, there was no treatment difference in HDD. Conversely, minorities had lower DUD in MBRP than RP (IRR = 0.03, 95% CI: 0.01, 0.10), whereas for whites there was no treatment difference in DUD. Group racial/ethnic composition was a significant moderator. Participants in groups with more than half whites had lower HDD in MBRP than RP (IRR = 0.01, 95% CI: 0, 0.09), whereas for participants in groups with more than half minorities there was no treatment difference in HDD. Exploratory analyses suggested MBRP resulted in better outcomes than RP when individual race/ethnic status was reflected in the group race/ethnicity (i.e., whites in groups with more than half whites or minorities in groups with more than half minorities). Among whites, MBRP appears to be more effective than RP in preventing heavy drinking relapse. However, among racial/ethnic minorities, MBRP appears to more effective than RP in preventing drug use relapse. This suggests that the interaction between individual race/ethnicity and group composition may influence primary outcomes. Copyright © 2018 Elsevier Ltd. All rights reserved.
Gender Minority Stress and Depressive Symptoms in Transitioned Swiss Transpersons
Corbisiero, Salvatore; Schaefer, Dirk J.; Jenewein, Josef; Schneeberger, Andres; Kuhn, Annette; Garcia Nuñez, David
2018-01-01
Compared to the general population, transpersons are exposed to higher levels of discrimination and violence. The stigmatization of transpersons can lead to physical and psychological problems. In particular, transindividuals exhibit a higher prevalence of depression compared to the cispopulation. The gender minority stress model (GMSM) provides a comprehensive theoretical basis to interpret these biopsychosocial interactions. Using the GMSM, this study aimed to identify associations between experience of stigmatization and the mental health of transitioned transpersons using correlational analyses and multiple regression models. In total, 143 transpersons were recruited. Multivariate analyses identified three variables (i.e., unemployment, nonaffirmation of gender identity, and internalized transphobia) to explain variance of depressive symptoms. Furthermore, a mediation of the proximal factors between distal factors and depressive symptoms was found. However, the moderating effect of resilience factors was not demonstrated. The results confirmed the importance of distal and proximal minority stressors for the mental health of transpersons. At the same time, the protective influence of resilience factors seemed to be surprisingly minor. In the treatment of transpersons, practitioners should not only focus on somatic aspects, but also consider the person's previous experiences of stigmatization. PMID:29850581
Niranjan, Soumya J; Durant, Raegan W; Wenzel, Jennifer A; Cook, Elise D; Fouad, Mona N; Vickers, Selwyn M; Konety, Badrinath R; Rutland, Sarah B; Simoni, Zachary R; Martin, Michelle Y
2017-08-03
The study of disparities in minority recruitment to cancer clinical trials has focused primarily on inquiries among minority patient populations. However, clinical trial recruitment is complex and requires a broader appreciation of the multiple factors that influence minority participation. One area that has received little attention is minority recruitment training for professionals who assume various roles in the clinical trial recruitment process. Therefore, we assessed the perspectives of cancer center clinical and research personnel on their training and education needs toward minority recruitment for cancer clinical trials. Ninety-one qualitative interviews were conducted at five U.S. cancer centers among four stakeholder groups: cancer center leaders, principal investigators, referring clinicians, and research staff. Interviews were recorded and transcribed. Qualitative analyses focused on response data related to training for minority recruitment for cancer clinical trials. Four prominent themes were identified: (1) Research personnel are not currently being trained to focus on recruitment and retention of minority populations; (2) Training for minority recruitment and retention provides for a specific focus on factors influencing minority research participation; (3) Training on cultural awareness may help to bridge cultural gaps between potential minority participants and research professionals; (4) Views differ regarding the importance of research personnel training designed to focus on recruitment of minority populations. There is a lack of systematic training for minority recruitment. Many stakeholders acknowledged the benefits of minority recruitment training and welcomed training that focuses on increasing cultural awareness to increase the participation of minorities in cancer clinical trials.
A comparison between different finite elements for elastic and aero-elastic analyses.
Mahran, Mohamed; ELsabbagh, Adel; Negm, Hani
2017-11-01
In the present paper, a comparison between five different shell finite elements, including the Linear Triangular Element, Linear Quadrilateral Element, Linear Quadrilateral Element based on deformation modes, 8-node Quadrilateral Element, and 9-Node Quadrilateral Element was presented. The shape functions and the element equations related to each element were presented through a detailed mathematical formulation. Additionally, the Jacobian matrix for the second order derivatives was simplified and used to derive each element's strain-displacement matrix in bending. The elements were compared using carefully selected elastic and aero-elastic bench mark problems, regarding the number of elements needed to reach convergence, the resulting accuracy, and the needed computation time. The best suitable element for elastic free vibration analysis was found to be the Linear Quadrilateral Element with deformation-based shape functions, whereas the most suitable element for stress analysis was the 8-Node Quadrilateral Element, and the most suitable element for aero-elastic analysis was the 9-Node Quadrilateral Element. Although the linear triangular element was the last choice for modal and stress analyses, it establishes more accurate results in aero-elastic analyses, however, with much longer computation time. Additionally, the nine-node quadrilateral element was found to be the best choice for laminated composite plates analysis.
Bulk and rare earth abundances in the Luna 16 soil levels A and D.
NASA Technical Reports Server (NTRS)
Gillum, D. E.; Ehmann, W. D.; Wakita, H.; Schmitt, R. A.
1972-01-01
Determination of the abundances of major, minor, and trace elements by means of sequential INAA (instrumental neutron activation analysis) in two Luna 16 soils, at levels A (about 7 cm depth) and D (about 30 cm depth). Abundances of the bulk elements in Luna 16 soils generally agree with the values reported by Vinogradov (1971). Elemental abundances of both bulk and trace elements are nearly the same for the two A and D soil levels. Overall, the chemical compositions of the two Luna 16 soils are more closely related to Apollo 11 soil 10084 than to Apollo 12 and 14 soils, with the exception of TiO2 abundances.-
Trace geochemistry of lunar material
NASA Technical Reports Server (NTRS)
Morrison, G. H.
1974-01-01
The lunar samples from the Apollo 16 and 17 flights which were analyzed include soil, igneous rock, anorthositic gabbro, orange soil, subfloor basalt, and norite breccia. Up to 57 elements including majors, minors, rare earths and other trace elements were determined in the lunar samples. The analytical techniques used were spark source mass spectrometry and neutron activation analysis. The latter was done either instrumentally or with group radiochemical separations. The differences in abundances of the elements in lunar soils at the various sites are discussed. With regard to the major elements only Si is about the same at all the sites. A detailed analysis which was performed on a sample of the Allende meteorite is summarized.
Durant, Raegan W; Wenzel, Jennifer A; Scarinci, Isabel C; Paterniti, Debora A; Fouad, Mona N; Hurd, Thelma C; Martin, Michelle Y
2014-04-01
The study of disparities in minority recruitment to cancer clinical trials has focused primarily on inquiries among minority populations. Yet very little is known about the perceptions of individuals actively involved in minority recruitment to clinical trials within cancer centers. Therefore, the authors assessed the perspectives of cancer center clinical and research personnel on barriers and facilitators to minority recruitment. In total, 91 qualitative interviews were conducted at 5 US cancer centers among 4 stakeholder groups: cancer center leaders, principal investigators, research staff, and referring clinicians. All interviews were recorded and transcribed. Qualitative analyses of response data was focused on identifying prominent themes related to barriers and facilitators to minority recruitment. The perspectives of the 4 stakeholder groups were largely overlapping with some variations based on their unique roles in minority recruitment. Four prominent themes were identified: 1) racial and ethnic minorities are influenced by varying degrees of skepticism related to trial participation, 2) potential minority participants often face multilevel barriers that preclude them from being offered an opportunity to participate in a clinical trial, 3) facilitators at both the institutional and participant level potentially encourage minority recruitment, and 4) variation between internal and external trial referral procedures may limit clinical trial opportunities for racial and ethnic minorities. Multilevel approaches are needed to address barriers and optimize facilitators within cancer centers to enhance minority recruitment for cancer clinical trials. © 2014 American Cancer Society.
Al Chawa, Taofik; Ludwig, Kerstin U; Fier, Heide; Pötzsch, Bernd; Reich, Rudolf H; Schmidt, Gül; Braumann, Bert; Daratsianos, Nikolaos; Böhmer, Anne C; Schuencke, Hannah; Alblas, Margrieta; Fricker, Nadine; Hoffmann, Per; Knapp, Michael; Lange, Christoph; Nöthen, Markus M; Mangold, Elisabeth
2014-06-01
The genes Gremlin-1 (GREM1) and Noggin (NOG) are components of the bone morphogenetic protein 4 pathway, which has been implicated in craniofacial development. Both genes map to recently identified susceptibility loci (chromosomal region 15q13, 17q22) for nonsyndromic cleft lip with or without cleft palate (nsCL/P). The aim of the present study was to determine whether rare variants in either gene are implicated in nsCL/P etiology. The complete coding regions, untranslated regions, and splice sites of GREM1 and NOG were sequenced in 96 nsCL/P patients and 96 controls of Central European ethnicity. Three burden and four nonburden tests were performed. Statistically significant results were followed up in a second case-control sample (n = 96, respectively). For rare variants observed in cases, segregation analyses were performed. In NOG, four rare sequence variants (minor allele frequency < 1%) were identified. Here, burden and nonburden analyses generated nonsignificant results. In GREM1, 33 variants were identified, 15 of which were rare. Of these, five were novel. Significant p-values were generated in three nonburden analyses. Segregation analyses revealed incomplete penetrance for all variants investigated. Our study did not provide support for NOG being the causal gene at 17q22. However, the observation of a significant excess of rare variants in GREM1 supports the hypothesis that this is the causal gene at chr. 15q13. Because no single causal variant was identified, future sequencing analyses of GREM1 should involve larger samples and the investigation of regulatory elements. © 2014 Wiley Periodicals, Inc.
NASA Astrophysics Data System (ADS)
Ford, K. E. Saavik; Paglione, Timothy; Robbins, Dennis; Mac Low, Mordecai-Mark; Agueros, Marcel A.
2015-01-01
AstroCom NYC is an NSF-funded partnership between astronomers at The City University of New York (CUNY), The American Museum of Natural History (AMNH) and Columbia University, designed to increase recruitment and retention of underrepresented minorities in astronomy and astrophysics. I will discuss the major program elements, including: recruitment, student selection, a 'Methods of Scientific Research' (MSR) course, summer research experience and ongoing structured mentoring. I will also discuss how the programs are integrated into each institution and present progress updates from our first two years.
PIXE analysis of ancient Chinese Changsha porcelain
NASA Astrophysics Data System (ADS)
Lin, E. K.; Yu, Y. C.; Wang, C. W.; Liu, T. Y.; Wu, C. M.; Chen, K. M.; Lin, S. S.
1999-04-01
In this work, proton induced X-ray emission (PIXE) method was applied for the analysis of ancient Chinese Changsha porcelain produced in the Tang dynasty (AD 618-907). A collection of glazed potsherds was obtained in the complex of the famous kiln site at Tongguan, Changsha city, Hunan province. Studies of elemental composition were carried out on ten selected Changsha potsherds. Minor and trace elements such as Ti, Mn, Fe, Co, Cu, Rb, Sr, and Zr in the material of the porcelain glaze were determined. Variation of these elements from sample to sample was investigated. Details of results are presented and discussed.
DeWeese, Lawrence R.; Stephens, Verlin C.; Short, Terry M.; Dubrovsky, Neil M.
2007-01-01
The U.S. Geological Survey National Water-Quality Assessment Program collected tissue samples from a variety of aquatic organisms during 1992-1999 within 47 study units across the United States. These tissue samples were collected to determine the occurrence and distribution of 20 major and minor trace elements in aquatic organisms. This report presents the tissue trace-element concentration data, sample summaries, and concentration statistics for 1,457 tissue samples representing 76 species or groups of fish, aquatic invertebrates, and plants were collected at 824 sampling sites.
NASA Technical Reports Server (NTRS)
Kuehner, S. M.; Laughlin, J. R.; Grossman, L.; Johnson, M. L.; Burnett, D. S.
1989-01-01
The applicability of ion microprobe (IMP) for quantitative analysis of minor elements (Sr, Y, Zr, La, Sm, and Yb) in the major phases present in natural Ca-, Al-rich inclusions (CAIs) was investigated by comparing IMP results with those of an electron microprobe (EMP). Results on three trace-element-doped glasses indicated that it is not possible to obtain precise quantitative analysis by using IMP if there are large differences in SiO2 content between the standards used to derive the ion yields and the unknowns.
Unraveling Appalachian tectonics: domain analysis of topographic lineaments in Pennsylvania
NASA Astrophysics Data System (ADS)
Karimi, B.; Schon, K.; Nussbaum, G. W.; Storer, N. D.; McGuire, J. L.; Hardcastle, K.
2016-12-01
Litho-tectonic provinces provide different components of a regions' tectonic history, and are identified as spatial entities with common structural elements, or a number of contiguous related elements. The province boundaries are easily identified when geomorphic expressions are distinct, or significant rock exposure allows for little uncertainty. When exposures are limited, locations of boundaries between provinces are uncertain. In such instances, satellite imagery can be quite advantageous, as tectonically sourced features (faults, folds, fractures, and joints) may exert a strong control on topographic patterns by creating pathways for weathering and erosion. Lineament analyses of topography often focus on well-pronounced tectonic features to interpret regional tectonics. We suggest that lineament analyses including all topographic features may include more subtle tectonic features, resulting in the identification of minor heterogeneities within litho-tectonic provinces. Our study focuses on Appalachian tectonics, specifically in Pennsylvania (PA), home to the Appalachian Orocline and 5 distinct tectonic provinces. Using hillshades from a digital elevation model (DEM) of PA, we manually pick all topographic lineaments 1 km or greater, discriminating only against man-made structures. The final lineament coverage of the state is subdivided into smaller areas for which rose diagrams were prepared. The dominant lineament trends were compared and associated with known structural features. Peaks with no known source are marked as possible tectonic features requiring further research. A domain analysis is performed on the lineament data to identify the extent and interplay of swarms, followed by an investigation of their azimuthal compatibility. We present the results of our domain analysis of all topographic lineaments in the context of identifying litho-tectonic provinces associated with Appalachian tectonics in Pennsylvania, and possible heterogeneities within them.
NASA Astrophysics Data System (ADS)
Anantharaman, K.; Breier, J. A., Jr.; Jain, S.; Reed, D. C.; Dick, G.
2015-12-01
Deep-sea hydrothermal plumes occur when hot fluids from hydrothermal vents replete with chemically reduced elements and compounds like sulfide, methane, hydrogen, ammonia, iron and manganese mix with cold, oxic seawater. Chemosynthetic microbes use these reduced chemicals to power primary production and are pervasive throughout the deep sea, even at sites far removed from hydrothermal vents. Although neutrally-buoyant hydrothermal plumes have been well-studied, rising hydrothermal plumes have received little attention even though they represent an important interface in the deep-sea where microbial metabolism and particle formation processes control the transformation of important elements and impact global biogeochemical cycles. In this study, we used genome-resolved metagenomic analyses and thermodynamic-bioenergetic modeling to study the microbial ecology of rising hydrothermal plumes at five different hydrothermal vents spanning a range of geochemical gradients at the Eastern Lau Spreading Center (ELSC) in the Western Pacific Ocean. Our analyses show that differences in the geochemistry of hydrothermal vents do not manifest in microbial diversity and community composition, both of which display only minor variance across ELSC hydrothermal plumes. Microbial metabolism is dominated by oxidation of reduced sulfur species and supports a diversity of bacteria, archaea and viruses that provide intriguing insights into metabolic plasticity and virus-mediated horizontal gene transfer in the microbial community. The manifestation of sulfur oxidation genes in hydrogen and methane oxidizing organisms hints at metabolic opportunism in deep-sea microbes that would enable them to respond to varying redox conditions in hydrothermal plumes. Finally, we infer that the abundance, diversity and metabolic versatility of microbes associated with sulfur oxidation impart functional redundancy that could allow it to persist in the dynamic settings of hydrothermal plumes.
Mereish, Ethan H; Poteat, V Paul
2015-07-01
Sexual minorities (e.g., lesbians, gay men, bisexual individuals) are at an increased risk for poorer mental and physical health outcomes than heterosexuals, and some of these health disparities relate to minority stressors such as discrimination. Yet, there is little research elucidating pathways that predict health or that promote resiliency among sexual minorities. Building on the minority stress model, the present study utilized relational cultural theory to situate sexual minority health within a relational framework. Specifically, the study tested mediators of the relationships between distal (i.e., discrimination, rejection, victimization) and proximal stressors (i.e., internalized homophobia, sexual orientation concealment) and psychological and physical distress for sexual minorities. Among 719 sexual minority adults, structural equation modeling analyses were used to test 4 models reflecting the mediating effects of shame, poorer relationships with a close peer and the lesbian/gay/bisexual/transgender (LGBT) community, and loneliness on the associations between minority stressors and psychological distress (i.e., depression and anxiety) and physical distress (i.e., distressing physical symptoms). As hypothesized, the associations between distal and proximal minority stressors and distress were mediated by shame, poorer relationships with a close peer and the LGBT community, and loneliness. Findings underscore the possible relational and interpersonal mechanisms by which sexual minority stressors lead to psychological and physical distress. (c) 2015 APA, all rights reserved).
Increasing the Efficiency of Electron Microprobe Measurements of Minor and Trace Elements in Rutile
NASA Astrophysics Data System (ADS)
Neill, O. K.; Mattinson, C. G.; Donovan, J.; Hernández Uribe, D.; Sains, A.
2016-12-01
Minor and trace element contents of rutile, an accessory mineral found in numerous lithologic settings, has many applications for interpreting earth systems. While these applications vary widely, they share a need for precise and accurate elemental measurements. The electron microprobe can be used to measure rutile compositions, although long X-ray counting times are necessary to achieve acceptable precision. Continuum ("background") intensity can be estimated using the iterative Mean Atomic Number (MAN) method of Donovan and Tingle (1996), obviating the need for direct off-peak background measurements, and reducing counting times by half. For this study, several natural and synthetic rutiles were measured by electron microprobe. Data was collected once but reduced twice, using off-peak and an MAN background corrections, allowing direct comparison of the two methods without influence of other variables (counting time, analyte homogeneity, beam current, calibration standards, etc.). These measurements show that, if a "blank" correction (Donovan et al., 2011, 2016) is used, minor and trace elements of interest can be measured in rutile using the MAN background method in half the time of traditional off-peak measurements, without sacrificing accuracy or precision (Figure 1). This method has already been applied to Zr-in-rutile thermometry of ultra-high pressure metamorphic rocks from the North Qaidam terrane in northwest China. Finally, secondary fluorescence of adjacent phases by continuum X-rays can lead to artificially elevated concentrations. For example, when measuring Zr, care should be taken to avoid analytical spots within 100 microns of zircon or baddeleyite crystals. References: 1) J.J. Donovan and T.N Tingle (1996) J. Microscopy, 2(1), 1-7 2) J.J. Donovan, H.A. Lowers, and B.G. Rusk (2011) Am. Mineral., 96, 274282 3) J.J. Donovan, J.W. Singer and J.T. Armstrong (2016) Am. Mineral., 101, 1839-1853 4) G.L. Lovizotto et al. (2009) Chem. Geol., 261, 346-369
NASA Astrophysics Data System (ADS)
Lamborg, C. H.; Buesseler, K. O.; Lam, P. J.
2008-07-01
As part of the Vertical Transport in the Global Ocean (VERTIGO) program, we collected and analyzed sinking particles using sediment traps at three depths in the oceanic mesopelagic zone and at two biogeochemically contrasting sites (N. Central Pacific at ALOHA; N. Pacific Western Subarctic Gyre at K2). In this paper, we present the results of minor and trace element determinations made on these samples. Minor and trace elements in the sinking material showed 2 trends in flux with depth: increasing and constant. The sinking particulate phase of some elements (Al, Fe, Mn) was dominated by material of lithogenic origin and exhibited flux that was constant with depth and consistent with eolian dust inputs (ALOHA), or increasing in flux with depth as a result of lateral inputs from a shelf (K2). This shelf-derived material also appears to have been confined to very small particles, whose inherent sinking rates are slow, and residence time within the mesopelagic "twilight zone" would be consequently long. Furthermore, the flux of this material did not change with substantial changes in the rain of biogenic material from the surface (K2), suggesting mechanistic decoupling from the flux of organic carbon and macronutrients. Micronutrient (Fe, Co, Zn and Cu) fluxes examined in a 1-D mass balance suggest widely differing sources and sinks in the water column as well as impacts from biological uptake and regeneration. For example, total Fe fluxes into and out of the euphotic zone appeared to be dominated by lithogenic material and far exceed biological requirements. The export flux of Fe, however, appeared to be balanced by the eolian input of soluble Fe. For Zn and Cu, the situation is reversed, with atmospheric inputs insufficient to support fluxes, and the cycling therefore dominated by the draw down of an internal pool. For Co, the situation lies in between, with important, but ultimately insufficient atmospheric inputs.
NASA Technical Reports Server (NTRS)
Papike, J. J.; Spilde, M. N.; Fowler, G. W.; Shearer, C. K.
1994-01-01
Considerable attention has been paid recently to the primitive achondrites because they may form a link between chondrites and more differentiated achondrite meteorites. A recent paper by Miyamoto and Takeda addresses the thermal history of lodranites Yamato 74357 and MAC 88177 as inferred from chemical zoning of pyroxene and olivine determined by electron microprobe analyses. Their results suggested that interstitial melt was present and then extracted. We have taken the analysis of Lodran-type meteorites one step further by incorporating the techniques of Electromagnetic Pulse/Wavelength Dispersive Spectroscopy (EMP/WDS) compositional imaging and scanning ion mass spectroscopy (SIMS) analysis. Orthopyroxene in Lodran is strongly zoned in CaO, Al2O3, TiO2, and Cr2O3 within the last 10-30 microns from the grain boundaries. The rims are reversely zoned in Mg-Fe, exhibiting Mg enrichment, and compositions change from a fairly uniform Wo3En94 within the grains to Wo1En96 at the rims. CaO drops from 1.6 to 0.6 wt% and Al2O3, TiO2, and Cr2O3 exhibit similar depletions. MnO is fairly uniform throughout the grains at around 0.5 wt%. Olivine is also reversely zoned with respect to not only grain boundaries but also to fractures within the grains, giving many olivine grains a complex, patchy zoning pattern. Some of the core-rim trace-element systematics for orthopyroxene are illustrated. Because of the rather narrow zoned rims in Lodran orthopyroxene and the low trace-element abundances, it is difficult to clearly resolve the trace-element systematics. Nevertheless it is evident that the cores are enriched in the incompatible trace elements Ce, Nd, Dy, Er, Yb, Y, and Zr relative to the rims.
Andersen, Judith P; Zou, Christopher; Blosnich, John
2015-05-01
Prior research shows that health disparities exist between sexual minority and heterosexual individuals. We extend the literature by testing if the higher prevalence of childhood victimization experienced by sexual minority individuals accounts for lifetime health disparities. Heterosexual (n = 422) and sexual minority (n = 681) participants were recruited on-line in North America. Respondents completed surveys about their childhood victimization experiences (i.e., maltreatment by adults and peer victimization) and lifetime physician-diagnosed physical health conditions. Results showed that sexual minority individuals experienced higher prevalence of childhood victimization and lifetime physical health problems than heterosexuals. Mediation analyses indicated that maltreatment by adults and peer bullying explained the health disparities between sexual minority individuals and heterosexuals. This study is the first to show that multiple childhood victimization experiences may be one pathway to explain lifetime physical health disparities. Intervention programs reducing the perpetration of violence against sexual minority individuals are critical to reduce health care needs related to victimization experiences. Copyright © 2015 Elsevier Ltd. All rights reserved.
Tatum, Alexander K
2017-01-01
Previous psychological and public health research has highlighted the impact of legal recognition of same-sex relationships on individual identity and mental health. Using a sample of U.S. sexual minority (N = 313) and heterosexual (N = 214) adults, participants completed a battery of mental health inventories prior to the nationwide legalization of same-sex marriage. Analyses of covariance (ANCOVAs) examining identity revealed sexual minority participants living in states where same-sex marriage was banned experienced significantly higher levels of internalized homonegativity than sexual minority participants living in states where same-sex marriage was legal, even after controlling for state-level political climate. Mental health ANCOVAs revealed sexual minority participants residing in states without same-sex marriage experienced greater anxiety and lower subjective wellbeing compared to sexual minority participants residing in states with same-sex marriage and heterosexual participants residing in states with or without same-sex marriage. Implications for public policy and future research directions are discussed.
The minor third communicates sadness in speech, mirroring its use in music.
Curtis, Meagan E; Bharucha, Jamshed J
2010-06-01
There is a long history of attempts to explain why music is perceived as expressing emotion. The relationship between pitches serves as an important cue for conveying emotion in music. The musical interval referred to as the minor third is generally thought to convey sadness. We reveal that the minor third also occurs in the pitch contour of speech conveying sadness. Bisyllabic speech samples conveying four emotions were recorded by 9 actresses. Acoustic analyses revealed that the relationship between the 2 salient pitches of the sad speech samples tended to approximate a minor third. Participants rated the speech samples for perceived emotion, and the use of numerous acoustic parameters as cues for emotional identification was modeled using regression analysis. The minor third was the most reliable cue for identifying sadness. Additional participants rated musical intervals for emotion, and their ratings verified the historical association between the musical minor third and sadness. These findings support the theory that human vocal expressions and music share an acoustic code for communicating sadness.
Psychiatrists' views of compulsory psychiatric care of minors.
Turunen, Suvi; Välimäki, Maritta; Kaltiala-Heino, Riittakerttu
2010-01-01
Commitment to psychiatric care is in Finland allowed for minors in broader terms than for adults. Minors can be committed to and detained in involuntary psychiatric treatment if they suffer from severe mental disorder and fulfil the additional commitment criteria defined in the Mental Health Act. Adults can be committed to involuntary psychiatric care only if they are mentally ill (=psychotic), and fulfil the additional criteria. Involuntary treatment of minors has been increasing steadily since the Mental Health Act was passed in 1991. This study was set up to find out whether the Finnish child and adolescent psychiatrists agree with the need for defining broader commitment criteria for minors, and why. Semi-structured, reflexive dyadic interviews were carried out with 44 psychiatrists working with children and adolescents. The data was analysed using qualitative and quantitative content analysis. The analysis showed that broader commitment criteria for minors were favoured referring to developmental needs related to childhood and adolescence, prevention of mental illnesses and inadequacy of descriptive diagnosis in childhood and adolescence. The commitment criteria were rather seen as too narrow for adults than as too broad for minors, and the medical rights of minors were preferred over self-determination. Copyright 2009 Elsevier Ltd. All rights reserved.
ERIC Educational Resources Information Center
McPartland, James M.; And Others
Three separate reports are bound together in this volume. Each examines one area of the transition from school to work in order to identify how elements of the process differ for blacks and women compared to whites and white males, and how these elements might better meet the needs of blacks and women. The three papers, and their authors, are as…
NASA Astrophysics Data System (ADS)
Bourdin, C.; Douville, E.; Genty, D.
2009-12-01
A multi-elemental study focusing on earth-alkalis (Mg, Ca, Sr and Ba), uranium and rare-earth elements (REE) in the calcite of a stalagmite from the Chauvet Cave (SE of France) has been achieved by ICP-MS. The Chau-stm6 stalagmite which grew from 33 to 11.5 ky had already been dated and the published d13C and d18O profile is used as a paleoclimatic benchmark. Ba and Sr profiles show an abrupt concentration increase at the beginning of the last deglaciation whereas U and Mg feature a decreasing trend. REY (REE+yttrium) concentrations decrease markedly during early deglaciation (between 15 and 14.5 ky). The transition corresponds to a change from a slow to a fast growth rate. These variations can be explained by the crystallographic control of ionic radii of the minor elements: incorporation of small ions compared to Ca such as U, Mg, heavy REE are favoured during slow growth period (i.e. glacial) whereas large ions such as Ba, Sr and light REE are preferentially precipitated during fast growth period (i.e. Bolling-Allerod). This crystallographic effect seems to be dominant here because the soil above the cave is sparse. And may not have played a major role on the opposite to the water-limestone interaction.
Lee, Rebecca E; Mama, Scherezade K; Adamus-Leach, Heather J
2012-01-01
Cardiometabolic risk factors such as obesity, excess percent body fat, high blood pressure, elevated resting heart rate and sedentary behavior have increased in recent decades due to changes in the environment and lifestyle. Neighborhood micro-environmental, street scale elements may contribute to health above and beyond individual characteristics of residents. To investigate the relationship between neighborhood street scale elements and cardiometabolic risk factors among inactive ethnic minority women. Women (N = 410) completed measures of BMI, percent body fat, blood pressure, resting heart rate, sedentary behavior and demographics. Trained field assessors completed the Pedestrian Environment Data Scan in participants' neighborhoods. Data were collected from 2006-2008. Multiple regression models were conducted in 2011 to estimate the effect of environmental factors on cardiometabolic risk factors. Adjusted regression models found an inverse association between sidewalk buffers and blood pressure, between traffic control devices and resting heart rate, and a positive association between presence of pedestrian crossing aids and BMI (ps<.05). Neighborhood attractiveness and safety for walking and cycling were related to more time spent in a motor vehicle (ps<.05). Findings suggest complex relationships among micro-environmental, street scale elements that may confer important cardiometabolic benefits and risks for residents. Living in the most attractive and safe neighborhoods for physical activity may be associated with longer times spent sitting in the car.
Abandoned mine slags analysis by EPMA WDS X-ray mapping
NASA Astrophysics Data System (ADS)
Guimarães, F.; Rosado, L.; Morais, C.; Candeias, A. E.; Pinto, A. P.; Mirão, J.
2010-02-01
Mining activity on the Iberian Pyritic Belt (Portugal and Spain) started before Phoenician times, became particularly intense during the Roman occupation of the Iberian Peninsula (for gold), and after the industrial revolution (for gold, copper, zinc, lead and sulphur). The commonest ore of this region is a massive polymetalic sulphide accumulation, where pyrite (FeS2) is the main mineral, with variable concentrations of chalcopyrite (CuFeS2), sphalerite (ZnS), galena (PbS), arsenopyrite (FeAsS2), other sulphides and sulfosalts which include minor elements like Mn, Co, Ni, Se, Cd, Sb, Te, Hg and Bi. Some of the main and minor elements of these ores are hazardous and the drainage basins of pollutant source areas often induce health concerns in the resident population. Electron probe microanalysis study followed previous optical and XRD analysis of the slags. The study focused on the identification of phases how sulphide and metallic phases are distributed within the material and infer about leachable elements during weathering. Electron probe X-ray maps show evidences of different behaviour between the elements: Ca and Zn are completely leached; iron is retained in oxyhydroxides, lead and arsenic precipitate as sulphates. Electron probe microanalysis studies are essential to understand complex materials as earth materials. Nevertheless, care is required to a correct interpretation of data and most quantitative compositional data are not trustworthy.
NASA Astrophysics Data System (ADS)
Eriksson, Patrick G.; Reczko, Boris F. F.; Jaco Boshoff, A.; Schreiber, Ute M.; Van der Neut, Markus; Snyman, Carel P.
1995-06-01
Three architectural elements are identified in the Lower Proterozoic Magaliesberg Formation (Pretoria Group, Transvaal Supergroup) of the Kaapvaal craton, South Africa: (1) medium- to coarse-grained sandstone sheets; (2) fine- to medium-grained sandstone sheets; and (3) mudrock elements. Both sandstone sheet elements are characterised by horizontal lamination and planar cross-bedding, with lesser trough cross-bedding, channel-fills and wave ripples, as well as minor desiccated mudrock partings, double-crested and flat-topped ripples. Due to the local unimodal palaeocurrent patterns in the medium- to coarse-grained sandstone sheets, they are interpreted as ephemeral braid-delta deposits, which were subjected to minor marine reworking. The predominantly bimodal to polymodal palaeocurrent trends in the fine- to medium-grained sandstone sheets are inferred to reflect high-energy macrotidal processes and more complete reworking of braid-delta sands. The suspension deposits of mudrocks point to either braid-delta channel abandonment, or uppermost tidal flat sedimentation. The depositional model comprises ephemeral braid-delta systems which debouched into a high-energy peritidal environment, around the margins of a shallow epeiric sea on the Kaapvaal craton. Braid-delta and tidal channel dynamics are inferred to have been similar. Fine material in the Magaliesberg Formation peritidal complexes indicates that extensive aeolian removal of clay does not seem applicable to this example of the early Proterozoic.
Mereish, Ethan H; Katz-Wise, Sabra L; Woulfe, Julie
2017-08-01
Bisexual individuals are at higher risk for poor mental health outcomes compared to heterosexual as well as lesbian and gay individuals and experience minority stressors, such as discrimination, from both heterosexual and sexual minority communities. However, there is little research examining the negative effects of bisexual-specific minority stressors on bisexual individuals' mental health as well as psychological factors that might help explain minority stressors' deleterious effects. This research examined the effects of distal minority stressors (i.e., anti-bisexual experiences from both heterosexual as well as lesbian and gay people) and proximal stressors (i.e., internalized heterosexism and sexual orientation concealment) on psychological distress and suicidality among bisexual adults (N = 503). Building on the relational framing of the minority stress model, we also tested one relational factor (i.e., loneliness) as a mediator of the associations between distal and proximal minority stressors and poor mental health (i.e., psychological distress and suicidality). Structural equation modeling analyses were used to test the mediating effects of loneliness on the associations between minority stressors and psychological distress and suicidality. Although distal and proximal minority stressors were not associated with each other, loneliness mediated the effects of distal and proximal minority stressors on psychological distress and suicidality. The results of this study underscore the importance of targeting bisexual-specific minority stressors as well as loneliness in preventive interventions to improve the mental health of bisexual individuals.
XTCE. XML Telemetry and Command Exchange Tutorial
NASA Technical Reports Server (NTRS)
Rice, Kevin; Kizzort, Brad; Simon, Jerry
2010-01-01
An XML Telemetry Command Exchange (XTCE) tutoral oriented towards packets or minor frames is shown. The contents include: 1) The Basics; 2) Describing Telemetry; 3) Describing the Telemetry Format; 4) Commanding; 5) Forgotten Elements; 6) Implementing XTCE; and 7) GovSat.
12 CFR 225.8 - Capital planning.
Code of Federal Regulations, 2013 CFR
2013-01-01
... instrument, a payment of common or preferred stock dividends, a payment that may be temporarily or... stock repurchases; the strategies for addressing potential capital shortfalls; and the internal...-common elements of tier 1 capital, including perpetual preferred stock and related surplus, minority...
ERIC Educational Resources Information Center
McCann, Guy
With minor modifications, an advertising fundamentals course can stimulate creative development and provide career direction while it presents the basic elements of advertising. A group presentation introduces students to research and familiarizes them with the conflict resolution process useful in preparing advertising. A group project arranges…
NASA Astrophysics Data System (ADS)
Corrigan, Catherine M.; Chabot, Nancy L.; McCoy, Timothy J.; McDonough, William F.; Watson, Heather C.; Saslow, Sarah A.; Ash, Richard D.
2009-05-01
To better understand the partitioning behavior of elements during the formation and evolution of iron meteorites, two sets of experiments were conducted at 1 atm in the Fe-Ni-P system. The first set examined the effect of P on solid metal/liquid metal partitioning behavior of 22 elements, while the other set explored the effect of the crystal structures of body-centered cubic (α)- and face-centered cubic (γ)-solid Fe alloys on partitioning behavior. Overall, the effect of P on the partition coefficients for the majority of the elements was minimal. As, Au, Ga, Ge, Ir, Os, Pt, Re, and Sb showed slightly increasing partition coefficients with increasing P-content of the metallic liquid. Co, Cu, Pd, and Sn showed constant partition coefficients. Rh, Ru, W, and Mo showed phosphorophile (P-loving) tendencies. Parameterization models were applied to solid metal/liquid metal results for 12 elements. As, Au, Pt, and Re failed to match previous parameterization models, requiring the determination of separate parameters for the Fe-Ni-S and Fe-Ni-P systems. Experiments with coexisting α and γ Fe alloy solids produced partitioning ratios close to unity, indicating that an α versus γ Fe alloy crystal structure has only a minor influence on the partitioning behaviors of the trace element studied. A simple relationship between an element's natural crystal structure and its α/γ partitioning ratio was not observed. If an iron meteorite crystallizes from a single metallic liquid that contains both S and P, the effect of P on the distribution of elements between the crystallizing solids and the residual liquid will be minor in comparison to the effect of S. This indicates that to a first order, fractional crystallization models of the Fe-Ni-S-P system that do not take into account P are appropriate for interpreting the evolution of iron meteorites if the effects of S are appropriately included in the effort.
Craig, Shelley L; McInroy, Lauren B; D'Souza, Sandra A; Austin, Ashley; McCready, Lance T; Eaton, Andrew D; Shade, Leslie R; Wagaman, M Alex
2017-09-28
Sexual and gender minority youth are a population in peril, exemplified by their disproportionate risk of negative experiences and outcomes. Sexual and gender minority youth may be particularly active users of information and communication technologies (ICTs), and it is important to identify the potential contributions of ICTs to their resilience and well-being. Our aim was to (1) investigate the use of ICTs by sexual and gender minority youth, (2) identify the ways that ICTs influence the resilience and coping of sexual and gender minority youth, focusing on promotion of well-being through self-guided support-seeking (particularly using mobile devices), (3) develop a contextually relevant theoretical conceptualization of resilience incorporating minority stress and ecological approaches, (4) generate best practices and materials that are accessible to multiple interested groups, and (5) identify whether video narratives are a viable alternative to collect qualitative responses in Web-based surveys for youth. Mixed methods, cross-sectional data (N=6309) were collected via a Web-based survey from across the United States and Canada from March-July 2016. The sample was generated using a multipronged, targeted recruitment approach using Web-based strategies and consists of self-identified English-speaking sexual and gender minority youth aged 14-29 with technological literacy sufficient to complete the Web-based survey. The survey was divided into eight sections: (1) essential demographics, (2) ICT usage, (3) health and mental health, (4) coping and resilience, (5) sexual and gender minority youth identities and engagement, (6) fandom communities, (7) nonessential demographics, and (8) a video submission (optional, n=108). The option of a 3-5 minute video submission represents a new research innovation in Web-based survey research. Data collection is complete (N=6309), and analyses are ongoing. Proposed analyses include (1) structural equation modeling of quantitative data, (2) grounded theory analysis of qualitative data, and (3) an integrative, mixed methods analysis using a data transformation design. Theoretical and methodological triangulation of analyses integrates an interwoven pattern of results into a comprehensive picture of a phenomenon. Results will be reported in 2017 and 2018. This research study will provide critical insights into the emerging use of ICTs by sexual and gender minority youth and identify intervention strategies to improve their well-being and reduce risks encountered by this vulnerable population. Implications for practice, research, and knowledge translation are provided. ©Shelley L Craig, Lauren B McInroy, Sandra A D'Souza, Ashley Austin, Lance T McCready, Andrew D Eaton, Leslie R Shade, M Alex Wagaman. Originally published in JMIR Research Protocols (http://www.researchprotocols.org), 28.09.2017.
Final Environmental Assessment for Constructing a Magnet School at Laughlin Air Force Base, Texas
2016-10-01
agencies on the human health and environmental conditions in minority and low-income populations. Environmental justice analyses are performed to identify...potential disproportionately high and adverse human health or environmental effects from proposed federal actions on minority or low-income populations...considered to assess the potential for disproportionately high and adverse human health or environmental effects from proposed action on these
Sudhakar, S; Porcelvan, S; Francis, T.G. Tilak; Rathnamala, D; Radhakrishnan, R
2017-01-01
Introduction The postural adaptation is very common now a days in school going children, office desk oriented job, computer users and frequent mobile users, and in all major industrial workers. Several studies have documented a high incidence of postural abnormalities in a given population; however, methods of postural measurement were poorly defined. The implication of postural pro software to analyse the postural imbalance of upper body dysfunction is very rare and literature studies says that the kinematic changes in particular segment will produce pain/discomfort and thereby lesser productivity of subjects. Aim To evaluate the postural changes in subjects with upper body dysfunction after a corrective exercise strategy using postural analysis software and pectoralis minor muscle length testing. Materials and Methods After explaining the procedure and benefits, informed consent was taken from the participating subjects (age 25-55 years). Subjects with upper body dysfunction were randomly allocated into two groups (each group 30 subjects). The Group–A received the corrective exercise strategy and Group-B received the conventional exercise for eight weeks of study duration (15 reps each exercise, total duration of 40 min; four days/week. Pre and Post posture analysis were analysed using posture pro software along with flexibility of pectoralis minor was assessed using ruler scale method. Results After interpretation of data, both the group showed the postural alteration and pectoralis minor muscle length changes, p-value (p<0.01) of both group showed highly significant changes. But comparing the both groups, the subjects who received the corrective exercise strategy shown more percentage of improvement in posture alteration (56.25%), pectoralis minor muscle length changes (68.69%) than the conventional exercise received subjects in posture alteration (24.86%) and pectoralis minor muscle length changes (21.9%). Conclusion Altered postural changes and pectoralis minor muscle flexibility before and after the corrective exercise strategy evaluated by postural analysis software method shown to be a significant tool in clinical practice, which is easier and reproducible method. PMID:28893030
Sexual Minority Status, Peer Harassment, and Adolescent Depression
Martin-Storey, Alexa; Crosnoe, Robert
2012-01-01
The well-documented higher rates of depression among sexual minority youth are increasingly viewed by developmentalists as a byproduct of the stigmatization of sexual minority status in American society and of the negative impact this stigma has on the processes associated with depression. This study attempted to spur future research by testing Hatzenbuehler’s (2009) psychological mediation framework to investigate the ways in which peer harassment related to sexuality puts young people at risk by influencing the cognitive, social, and regulatory factors associated with depression. Analyses of 15 year olds in the NICHD Study of Early Child Care and Youth Development revealed that sexual minority status was largely associated with depressive outcomes via harassment, which was subsequently associated with depression via cognitive and social factors. Results point to various avenues for exploring the importance of the social world and self-concept for the outcomes of sexual minority adolescents in the future. PMID:22401842
Analysis of Minor Component Segregation in Ternary Powder Mixtures
NASA Astrophysics Data System (ADS)
Asachi, Maryam; Hassanpour, Ali; Ghadiri, Mojtaba; Bayly, Andrew
2017-06-01
In many powder handling operations, inhomogeneity in powder mixtures caused by segregation could have significant adverse impact on the quality as well as economics of the production. Segregation of a minor component of a highly active substance could have serious deleterious effects, an example is the segregation of enzyme granules in detergent powders. In this study, the effects of particle properties and bulk cohesion on the segregation tendency of minor component are analysed. The minor component is made sticky while not adversely affecting the flowability of samples. The segregation extent is evaluated using image processing of the photographic records taken from the front face of the heap after the pouring process. The optimum average sieve cut size of components for which segregation could be reduced is reported. It is also shown that the extent of segregation is significantly reduced by applying a thin layer of liquid to the surfaces of minor component, promoting an ordered mixture.
Application of Standards-Based Quantitative SEM-EDS Analysis to Oxide Minerals
NASA Astrophysics Data System (ADS)
Mengason, M. J.; Ritchie, N. W.; Newbury, D. E.
2016-12-01
SEM and EPMA analysis are powerful tools for documenting and evaluating the relationships between minerals in thin sections and for determining chemical compositions in-situ. The time and costs associated with determining major, minor, and some trace element concentrations in geologic materials can be reduced due to advances in EDS spectrometer performance and the availability of software tools such as NIST DTSA II to perform multiple linear least squares (MLLS) fitting of energy spectra from standards to the spectra from samples recorded under the same analytical conditions. MLLS fitting is able to overcome spectral peak overlaps among the transition-metal elements that commonly occur in oxide minerals, which had previously been seen as too difficult for EDS analysis, allowing for rapid and accurate determination of concentrations. The quantitative use of EDS is demonstrated in the chemical analysis of magnetite (NMNH 114887) and ilmenite (NMNH 96189) from the Smithsonian Natural History Museum Microbeam Standards Collection. Average concentrations from nine total spots over three grains are given in mass % listed as (recommended; measured concentration ± one standard deviation). Spectra were collected for sixty seconds live time at 15 kV and 10 nA over a 12 micrometer wide scan area. Analysis of magnetite yielded Magnesium (0.03; 0.04 ± 0.01), Aluminum (none given; 0.040 ± 0.006), Titanium (0.10; 0.11 ± 0.02), Vanadium (none given; 0.16 ± 0.01), Chromium (0.17; 0.14 ± 0.02), and Iron (70.71, 71.4 ± 0.2). Analysis of ilmenite yielded Magnesium (0.19; 0.183 ± 0.008), Aluminum (none given; 0.04 ± 0.02), Titanium (27.4, 28.1 ± 0.1), Chromium (none given; 0.04 ± 0.01), Manganese (3.69; 3.73 ± 0.03), Iron (36.18; 35.8 ± 0.1), and Niobium (0.64; 0.68 ± 0.03). The analysis of geologic materials by standards-based quantitative EDS can be further illustrated with chemical analyses of oxides from ocean island basalts representing several locations globally to illustrate the suitability of the method to the goal of evaluating trends in major and minor element concentrations and variability among locations. The shorter collection times of EDS, compared to WDS, allow greater sampling of the populations of oxides present as fine-grained quench products in addition to sampling larger inclusions hosted by silicate minerals.
Swami, Viren; Hendrikse, Sinead
2013-01-01
Previous work has suggested that ethnic minority women have more negative attitudes to cosmetic surgery than British Whites, but reasons for this are not fully understood. To overcome this dearth in the literature, the present study asked 250 British Asian and 250 African Caribbean university students to complete measures of attitudes to cosmetic surgery, cultural mistrust, adherence to traditional cultural values, ethnic identity salience, self-esteem, and demographics. Preliminary analyses showed that there were significant between-group differences only on cultural mistrust and self-esteem, although effect sizes were small (d values = .21-.37). Further analyses showed that more negative attitudes to cosmetic surgery were associated with greater cultural mistrust, stronger adherence to traditional values, and stronger ethnic identity salience, although these relationships were weaker for African Caribbean women than for British Asians. These results are discussed in relation to perceptions of cosmetic surgery among ethnic minority women.
Laser heterodyne system for obtaining height profiles of minor species in the atmosphere
NASA Technical Reports Server (NTRS)
Jain, S. L.; Saha, A. K.
1986-01-01
An infrared laser heterodyne system for obtaining height profiles of minor constituents of the atmosphere was developed and erected. A brief discription of the system is given. The system consists of a tunable CO2 waveguide laser in the 9 to 11 micrometer band, that is used as a local oscillator and a heliostat that follows the sun and brings in solar radiation, that is mixed with the laser beam in a high speed liquid nitrogen cooled mercury cadmium telluride detector. The detected signal is analysed in a RF spectrum analyser that allows tracing absorption line profiles. Absorption lines of a number of minor constituents in the troposphere and stratosphere, such as O3, NH3, H2O, SO2, ClO, N2O, are in the 9 to 11 micrometer band and overlap with that of CO2 laser range. The experimental system has been made operational and trial observations taken. Current measurements are limited to ozone height profiles. Results are presented.
Rockliffe, Lauren; Marlow, Laura A.V.; Bedford, Helen; McBride, Emily; Waller, Jo
2017-01-01
Abstract Objectives In England, uptake of human papillomavirus (HPV) vaccination to prevent HPV‐related cancer is lower among girls from ethnic minority backgrounds. We aimed to explore the factors that prevented ethnic minority parents from vaccinating, compared to White British nonvaccinating parents and vaccinating ethnic minority parents. Methods Interviews with 33 parents (n = 14 ethnic minority non‐vaccinating, n = 10 White British nonvaccinating, and n = 9 ethnic minority vaccinating) explored parents' reasons for giving or withholding consent for HPV vaccination. Data were analysed using Framework Analysis. Results Concerns about the vaccine were raised by all nonvaccinating ethnic minority parents, and they wanted information to address these concerns. External and internal influences affected parents' decisions, as well as parents' perceptions that HPV could be prevented using means other than vaccination. Reasons were not always exclusive to nonvaccinating ethnic minority parents, although some were, including a preference for abstinence from sex before marriage. Only ethnic minority parents wanted information provided via workshops. Conclusions Ethnic differences in HPV vaccination uptake may be partly explained by concerns that were only reported by parents from some ethnic groups. Interventions to improve uptake may need to tackle difficult topics like abstinence from sex before marriage, and use a targeted format. PMID:28231418
Life assessment of structural components using inelastic finite element analyses
NASA Technical Reports Server (NTRS)
Arya, Vinod K.; Halford, Gary R.
1993-01-01
The need for enhanced and improved performance of structural components subject to severe cyclic thermal/mechanical loadings, such as in the aerospace industry, requires development of appropriate solution technologies involving time-dependent inelastic analyses. Such analyses are mandatory to predict local stress-strain response and to assess more accurately the cyclic life time of structural components. The NASA-Lewis Research Center is cognizant of this need. As a result of concerted efforts at Lewis during the last few years, several such finite element solution technologies (in conjunction with the finite element program MARC) were developed and successfully applied to numerous uniaxial and multiaxial problems. These solution technologies, although developed for use with MARC program, are general in nature and can easily be extended for adaptation with other finite element programs such as ABAQUS, ANSYS, etc. The description and results obtained from two such inelastic finite element solution technologies are presented. The first employs a classical (non-unified) creep-plasticity model. An application of this technology is presented for a hypersonic inlet cowl-lip problem. The second of these technologies uses a unified creep-plasticity model put forth by Freed. The structural component for which this finite element solution technology is illustrated, is a cylindrical rocket engine thrust chamber. The advantages of employing a viscoplastic model for nonlinear time-dependent structural analyses are demonstrated. The life analyses for cowl-lip and cylindrical thrust chambers are presented. These analyses are conducted by using the stress-strain response of these components obtained from the corresponding finite element analyses.
The use of mosses as environmental metal pollution indicators.
Aceto, Maurizio; Abollino, Ornella; Conca, Raffaele; Malandrino, Mery; Mentasti, Edoardo; Sarzanini, Corrado
2003-01-01
The possibility of using mosses as environmental indicators of metal pollution has been investigated. Mosses of the species Bryum argenteum were collected from different parts of Piedmont (Italy), ranging from highly polluted areas to nearly uncontaminated mountain areas. Periodical samplings were planned in every site on a monthly base, in order to check variations of metal uptake throughout one year; correlations with pluviometric and thermal patterns were investigated for all sampling stations. On every moss sample 20 elements, ranging from major (K, P, Al, Ca, Fe and Mg) to minor (Mn, Na, Ti and Zn) and trace (As, Ba, Cd, Co, Cr, Cu, Li, Ni, Pb and Sr), were quantitatively determined by inductively coupled plasma-atomic emission spectrometry or graphite furnace-atomic absorption spectrometry, depending on the needed sensitivity. Statistical analyses, carried out with principal component analysis and cluster analysis methods, revealed that a good correlation exists between metal content in mosses and pollution degree in the areas sampled.
NASA Astrophysics Data System (ADS)
Murry, Adam T.
Science has been identified as a crucial element in the competitiveness and sustainability of America in the global economy. American citizens, especially minority populations, however, are not pursuing science education or careers. Past research has implicated ‘attitudes toward science’ as an important factor in the public’s participation in science. I applied Ajzen’s (1991) Theory of Planned Behavior to attitudes toward science to predict science-related sustainability-action intentions and evaluated whether scientists and Native Americans differed in their general attitudes toward science, cultural values, and specific beliefs about science. Analyses revealed that positive attitude toward science and the cultural value of individualism predicted intentions to engage with science-related sustainability actions. Unexpectedly, scientists and Native Americans did not differ in their cultural values or positive attitude toward science. However, Natives Americans held significantly more negative attitude toward science than scientists. Implications for science education and attitudes towards science theory and application are discussed.
Dust as a tipping element: The Bodélé Depression, Chad
Washington, Richard; Bouet, Christel; Cautenet, Guy; Mackenzie, Elisabeth; Ashpole, Ian; Engelstaedter, Sebastian; Lizcano, Gil; Henderson, Gideon M.; Schepanski, Kerstin; Tegen, Ina
2009-01-01
Dust plays a vital role in climate and biophysical feedbacks in the Earth system. One source of dust, the Bodélé Depression in Chad, is estimated to produce about half the mineral aerosols emitted from the Sahara, which is the world's largest source. By using a variety of new remote sensing data, regional modeling, trajectory models, chemical analyses of dust, and future climate simulations, we investigate the current and past sensitivity of the Bodélé. We show that minor adjustments to small features of the atmospheric circulation, such as the Bodélé Low-Level Jet, could profoundly alter the behavior of this feature. Dust production during the mid-Holocene ceased completely from this key source region. Although subject to a great deal of uncertainty, some simulations of the 21st century indicate the potential for a substantial increase in dust production by the end of the century in comparison with current values. PMID:19620716
Dependence of Nebular Heavy-element Abundance on H I Content for Spiral Galaxies
NASA Astrophysics Data System (ADS)
Robertson, Paul; Shields, Gregory A.; Davé, Romeel; Blanc, Guillermo A.; Wright, Audrey
2013-08-01
We analyze the galactic H I content and nebular log (O/H) for 60 spiral galaxies in the Moustakas et al. (2006a) spectral catalog. After correcting for the mass-metallicity relationship, we show that the spirals in cluster environments show a positive correlation for log (O/H) on DEF, the galactic H I deficiency parameter, extending the results of previous analyses of the Virgo and Pegasus I clusters. Additionally, we show for the first time that galaxies in the field obey a similar dependence. The observed relationship between H I deficiency and galactic metallicity resembles similar trends shown by cosmological simulations of galaxy formation including inflows and outflows. These results indicate the previously observed metallicity-DEF correlation has a more universal interpretation than simply a cluster's effects on its member galaxies. Rather, we observe in all environments the stochastic effects of metal-poor infall as minor mergers and accretion help to build giant spirals.
Mercurio, Mariano; Rossi, Manuela; Izzo, Francesco; Cappelletti, Piergiulio; Germinario, Chiara; Grifa, Celestino; Petrelli, Maurizio; Vergara, Alessandro; Langella, Alessio
2018-02-01
Fourteen samples of tourmaline from the Real Museo Mineralogico of Federico II University (Naples) have been characterized through multi-methodological investigations (EMPA-WDS, SEM-EDS, LA-ICP-MS, and FT-IR spectroscopy). The samples show different size, morphology and color, and are often associated with other minerals. Data on major and minor elements allowed to identify and classify tourmalines as follows: elbaites, tsilaisite, schorl, dravites, uvites and rossmanite. Non-invasive, non-destructive FT-IR and in-situ analyses were carried out on the same samples to validate this chemically-based identification and classification. The results of this research show that a complete characterization of this mineral species, usually time-consuming and expensive, can be successfully achieved through non-destructive FT-IR technique, thus representing a reliable tool for a fast classification extremely useful to plan further analytical strategies, as well as to support gemological appraisals. Copyright © 2017 Elsevier B.V. All rights reserved.
Bejdová, Šárka; Dupej, Ján; Krajíček, Václav; Velemínská, Jana; Velemínský, Petr
2018-01-01
One of the most fundamental issues in forensic anthropology is the determination of sex and population affinity based on various skeletal elements. Therefore, we compared the sexual dimorphism of the upper facial skeleton from a recent Czech population (twenty-first century) with that of a population from Early Modern Age Bohemia (sixteenth to eighteenth centuries). Methods of geometric morphometrics were applied. According to the results, sexual dimorphism in terms of size, shape, and form was statistically significant in both populations. The best results of sex estimation originated from analyses of form. Thus, both size and shape differences should be taken into account for determination of the sex. The accuracy of prediction achieved 91.1% for individuals in the recent population and 87.5% for individuals from the early modern population. Only minor differences were found between sexual dimorphism in the studied populations. We conclude that sexual dimorphism of the upper facial skeleton is stable during the relatively short time period.
Wirt, Laurie; Motyka, Jacek; Leach, David; Sass-Gustkiewicz, Maria; Szuwarzynski, Marek; Adamczyk, Zbigniew; Briggs, Paul; Meiers, Al
2003-01-01
The water chemistry of aquifers and streams in the Upper Silesia Ore District, Poland are affected by their proximity to zinc, lead, and silver ores and by ongoing mining activities that date back to the 11th century. This report presents hydrologic and water-quality data collected as part of a collaborative research effort of the U.S. Geological Survey and the University of Mining and Metallurgy in Cracow, Poland to study Mississippi-Valley-Type lead-zinc deposits. MVT deposits in the Upper Silesia Ore District (Fig. 1) were selected for detailed study because the Polish mining industry allowed access to collect samples from underground mines and mine-land property. Water-quality samples were collected from streams, springs, wells, underground mine seeps and drains; and mine-tailings ponds. Data include field measurements of specific conductance, pH, water temperature, and dissolved oxygen and laboratory analyses of major and minor inorganic constituents and selected trace-element constituents.
Hammad, Tarek A; Neyarapally, George A; Pinheiro, Simone P; Iyasu, Solomon; Rochester, George; Dal Pan, Gerald
2013-01-01
Due to the sparse nature of serious drug-related adverse events (AEs), meta-analyses combining data from several randomized controlled trials (RCTs) to evaluate drug safety issues are increasingly being conducted and published, influencing clinical and regulatory decision making. Evaluation of meta-analyses involves the assessment of both the individual constituent trials and the approaches used to combine them. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) reporting framework is designed to enhance the reporting of systematic reviews and meta-analyses. However, PRISMA may not cover all critical elements useful in the evaluation of meta-analyses with a focus on drug safety particularly in the regulatory-public health setting. This work was conducted to (1) evaluate the adherence of a sample of published drug safety-focused meta-analyses to the PRISMA reporting framework, (2) identify gaps in this framework based on key aspects pertinent to drug safety, and (3) stimulate the development and validation of a more comprehensive reporting tool that incorporates elements unique to drug safety evaluation. We selected a sample of meta-analyses of RCTs based on review of abstracts from high-impact journals as well as top medical specialty journals between 2009 and 2011. We developed a preliminary reporting framework based on PRISMA with specific additional reporting elements critical for the evaluation of drug safety meta-analyses of RCTs. The reporting of pertinent elements in each meta-analysis was reviewed independently by two authors; discrepancies in the independent evaluations were resolved through discussions between the two authors. A total of 27 meta-analyses, 12 from highest impact journals, 13 from specialty medical journals, and 2 from Cochrane reviews, were identified and evaluated. The great majority (>85%) of PRISMA elements were addressed in more than half of the meta-analyses reviewed. However, the majority of meta-analyses (>60%) did not address most (>80%) of the additional reporting elements critical for the evaluation of drug safety. Some of these elements were not addressed in any of the reviewed meta-analyses. This review included a sample of meta-analyses, with a focus on drug safety, recently published in high-impact journals; therefore, we may have underestimated the extent of the reporting problem across all meta-analyses of drug safety. Furthermore, temporal trends in reporting could not be evaluated in this review because of the short time interval selected. While the majority of PRISMA elements were addressed by most studies reviewed, the majority of studies did not address most of the additional safety-related elements. These findings highlight the need for the development and validation of a drug safety reporting framework and the importance of the current initiative by the Council for International Organizations of Medical Sciences (CIOMS) to create a guidance document for drug safety information synthesis/meta-analysis, which may improve reporting, conduct, and evaluation of meta-analyses of drug safety and inform clinical and regulatory decision making.
Boundary element analyses for sound transmission loss of panels.
Zhou, Ran; Crocker, Malcolm J
2010-02-01
The sound transmission characteristics of an aluminum panel and two composite sandwich panels were investigated by using two boundary element analyses. The effect of air loading on the structural behavior of the panels is included in one boundary element analysis, by using a light-fluid approximation for the eigenmode series to evaluate the structural response. In the other boundary element analysis, the air loading is treated as an added mass. The effect of the modal energy loss factor on the sound transmission loss of the panels was investigated. Both boundary element analyses were used to study the sound transmission loss of symmetric sandwich panels excited by a random incidence acoustic field. A classical wave impedance analysis was also used to make sound transmission loss predictions for the two foam-filled honeycomb sandwich panels. Comparisons between predictions of sound transmission loss for the two foam-filled honeycomb sandwich panels excited by a random incidence acoustic field obtained from the wave impedance analysis, the two boundary element analyses, and experimental measurements are presented.
Oh, Sam S.; Foreman, Marilyn G.; Celedón, Juan C.
2015-01-01
A key objective of the 1993 National Institutes of Health (NIH) Revitalization Act was to ensure inclusion of minorities in clinical research. We conducted a literature search for the period from 1993 to 2013 to examine whether racial/ethnic minorities are adequately represented in published research studies of pulmonary diseases, particularly NIH-funded studies. We found a marked underrepresentation of minorities in published clinical research on pulmonary diseases. Over the last 20 years, inclusion of members of racial or ethnic minority groups was reported (in MeSH terms, journal titles, and MEDLINE fields) in less than 5% of all NIH-funded published studies of respiratory diseases. Although a secondary analysis revealed that a larger proportion of NIH-funded studies included any minorities, this proportional increment mostly resulted from studies including relatively small numbers of minorities (which precludes robust race- or ethnic-specific analyses). Underrepresentation or exclusion of minorities from NIH-funded studies is likely due to multiple reasons, including insufficient education and training on designing and implementing population-based studies of minorities, inadequate motivation or incentives to overcome challenges in the recruitment and retention of sufficient numbers of members of racial/ethnic minorities, underrepresentation of minorities among respiratory scientists in academic medical centers, and a dearth of successful partnerships between academic medical centers and underrepresented communities. This problem could be remedied by implementing short-, medium-, and long-term strategies, such as creating incentives to conduct minority research, ensuring fair review of grant applications focusing on minorities, developing the careers of minority scientists, and facilitating and valuing research on minorities by investigators of all backgrounds. PMID:25584658
Burchard, Esteban G; Oh, Sam S; Foreman, Marilyn G; Celedón, Juan C
2015-03-01
A key objective of the 1993 National Institutes of Health (NIH) Revitalization Act was to ensure inclusion of minorities in clinical research. We conducted a literature search for the period from 1993 to 2013 to examine whether racial/ethnic minorities are adequately represented in published research studies of pulmonary diseases, particularly NIH-funded studies. We found a marked underrepresentation of minorities in published clinical research on pulmonary diseases. Over the last 20 years, inclusion of members of racial or ethnic minority groups was reported (in MeSH terms, journal titles, and MEDLINE fields) in less than 5% of all NIH-funded published studies of respiratory diseases. Although a secondary analysis revealed that a larger proportion of NIH-funded studies included any minorities, this proportional increment mostly resulted from studies including relatively small numbers of minorities (which precludes robust race- or ethnic-specific analyses). Underrepresentation or exclusion of minorities from NIH-funded studies is likely due to multiple reasons, including insufficient education and training on designing and implementing population-based studies of minorities, inadequate motivation or incentives to overcome challenges in the recruitment and retention of sufficient numbers of members of racial/ethnic minorities, underrepresentation of minorities among respiratory scientists in academic medical centers, and a dearth of successful partnerships between academic medical centers and underrepresented communities. This problem could be remedied by implementing short-, medium-, and long-term strategies, such as creating incentives to conduct minority research, ensuring fair review of grant applications focusing on minorities, developing the careers of minority scientists, and facilitating and valuing research on minorities by investigators of all backgrounds.
Roadmap of next generation minor body explorations in Japan
NASA Astrophysics Data System (ADS)
Yano, H.
As of the early 2004, more than 250,000 minor bodies in the solar system have been detected. Among them, several thousands of asteroids are determined orbital elements well and even multi-band spectroscopic observation from ground enables us to classify taxonomy of them in statistically valid numbers. On the other hand, there have been several 10,000s of meteorite and cosmic dust samples already collected in the terrestrial environment. Thus, asteroid studies in statistical manners are practically conducted by ground observation and meteoritic analyses. It is a unique contribution of planetary exploration to provide the ground truth which bridges between abundant database of the ground observation and that of the meteoritic analyses, by bringing samples back to the Earth from a particular asteroid investigated in-situ. In May 2003, JAXA/ISAS successfully launched the Hayabusa (MUSES-C) spacecraft as the first kind of such minor body exploration, which will bring surface samples of an S-type NEO back to the Earth in mid 2007. Many of Japanese planetary scientists hope to advance such sample return strategies as their new expertise in the post-Hayabusa era. Now the ISAS new minor body exploration working group is about to start. Mission candidates include multiple sample returns from known spectra asteroids, in order to complete the asteroid taxonomy-meteoritic connection issue as early as possible (next 10-20 years) with possible international collaborations. One of such ideas is the multiple rendezvous sample return mission to known spectra NEOs of both primitive types (i.e., C, P/D) and differentiated types (e.g., V, M). Another is fly-by investigation and sample collection of multiple asteroids that belong to a single main-belt family. It will provide direct information of the interior as well as collisional history of their parent body, a refractory planetesimal disrupted by mutual collisions in the early stage of the Solar System evolution. One scenario targets the Koronis family including the Ida-Gaspra system, the only family asteroid visited by spacecraft in the past, and its dust band. Another aims the Nysa-Polana Family, which has several spectral types. Also what ISAS is planning is the solar powered sail mission which will make fly-by observations of main belt asteroids as well as Jovian Trojan asteroids, most of which are D-type asteroids with the absence of water absorption lines. Understanding generic connections among the Trojans, short-period cometary nucleus and the outermost D-type asteroids in the main belt may be a clue of how to distinguish between asteroids and comets, depending upon where they originated with respect to heliocentric distance in the early solar system.
NASA Astrophysics Data System (ADS)
Midula, Pavol; Wiche, Oliver
2016-04-01
Bioavailability research presents an essential tool, in modern phytoremediation and phytomining technologies, allowing the estimation of plant available fractions of elements in soils. However, up to date, sufficient interdisciplinary knowledge on the biogeochemically impacted behavior of specific target elements, in particular Ge and REEs in mining affected soils and their uptake into strategically used plants is lacking. This presented work is focused on a correlation study between the concentrations of selected heavy metals, Ge and REEs in soils formed on the top of the dump-field of Davidschacht and the corresponding their concentrations in 12 vascular plant species. The mine-dump of Davidschacht, situated in the Freiberg (Saxony, Germany) municipality area was chosen as the study area, which has been considered to be a high contaminated enclave, due to the mining history of the region. In total 12 sampling sites with differing composition of plant species were selected. At each sampling site soil samples from a soil depth of 0 - 10 cm and samples of plant material (shoots) were taken. The soil samples were analysed for total concentration of elements, pH (H2O) and consequently analysed by 4-step sequential extraction (SE) to determine fractions of elements that are mobile (fraction 1), acid soluble (pH 5) (fraction 2), bound to organic and oxidizable matter (fraction 3) and bound to amorphic oxides (fraction 4). The plant material was decomposed by hydrofluoric acid in order to extract the elements. Concentrations of elements in soil extracts and digestion solutions were analysed by ICP-MS. For all species bioconcentration factor (BCF) was calculated of the total concentration of elements in order to investigate the bioaccumulation potential. Arsenic (As), cadmium (Cd) and lead (Pb) were chosen as the representative heavy metals. Within the REEs neodymium (Nd) and cerium (Ce) were selected as representatives for all REEs, since Nd and Ce correlated significant with the other elements from this group. High amounts of As, Cd, Pb in mould horizons were proved. The surprisingly highest concentrations were determined for As (in average 3328 mg kg-1). The results of the pH measurement indicates acid conditions (in average 4.86, min. 3.89) for whole mine heap. Due to the mobility of Cd and Pb in acid environment, a high mobility of Cd in mobile soil fractions (in average 0.58 mg kg-1) was found, that seems to be responsible for the Cd pollution of Freiberger Mulde river, situated near the dump-field in the East direction from the studied area. The Pb content was in the average 1513 mg kg-1. SE analyses shows, that only the minor amounts of these metals were accounted in fractions I - IV (As: 7.75 %, Pb: 5.48 %, Cd: 26.77 %). The total Ge content in soil samples was 2.7 mg.kg-1in average. The concentrations of Nd and Ce were 17.7 mg kg-1and 38.5 mg kg-1, which is even lower than the average Nd and Ce contents in the Earth crust. However, the concentration of Ge was roughly a factor of two higher, than this average showing a large pool of Ge that could be accessed by phytoextraction. The SE analyses shows, that the average in fractions I - IV is even much lower, than in the case of the above mentioned heavy metals in comparison with Ge (1.75 %), Nd (3.28 %) and Ce (3.12 %). The BCF calculated for plants shows, that the only element, which could be possibly used as the object of phytoaccumulation is Cd (the BCF > 1) in species Populus tremula (3.0, 1.7), Spirea douglasii (1.4, 2.2) and Tanacetum vulgare (3.2, 1.3) at the most sampling places. Since these species represent the natural occurring vegetation of the dump, the use of these species together with soil amendments enhancing the plant availability of elements in soil fractions hold promise for phytoextraction of economically valuable metalloids and consequently an in situ bioremediation of the dump field. This work was realised with the support of Christin Jahns on behalf of the Saxonia company and financial supported by grant scheme VEGA 1/0538/15 . The authors are grateful to students and laboratory assistants contributing in the field work and sample preparation.
Poon, Matthew; Schutz, Michael
2015-01-01
Acoustic cues such as pitch height and timing are effective at communicating emotion in both music and speech. Numerous experiments altering musical passages have shown that higher and faster melodies generally sound "happier" than lower and slower melodies, findings consistent with corpus analyses of emotional speech. However, equivalent corpus analyses of complex time-varying cues in music are less common, due in part to the challenges of assembling an appropriate corpus. Here, we describe a novel, score-based exploration of the use of pitch height and timing in a set of "balanced" major and minor key compositions. Our analysis included all 24 Preludes and 24 Fugues from Bach's Well-Tempered Clavier (book 1), as well as all 24 of Chopin's Preludes for piano. These three sets are balanced with respect to both modality (major/minor) and key chroma ("A," "B," "C," etc.). Consistent with predictions derived from speech, we found major-key (nominally "happy") pieces to be two semitones higher in pitch height and 29% faster than minor-key (nominally "sad") pieces. This demonstrates that our balanced corpus of major and minor key pieces uses low-level acoustic cues for emotion in a manner consistent with speech. A series of post hoc analyses illustrate interesting trade-offs, with sets featuring greater emphasis on timing distinctions between modalities exhibiting the least pitch distinction, and vice-versa. We discuss these findings in the broader context of speech-music research, as well as recent scholarship exploring the historical evolution of cue use in Western music.
NASA Astrophysics Data System (ADS)
Tian, J.; Xie, X.; Jin, H.; Wang, P.; Jian, Z.
2009-12-01
Energy dispersive X-ray fluorescence (XRF) scanning technology provides the most accurate and most economic analytical methods for the determination of major and minor elements of the deep-sea sediment ranging from sodium (11) to uranium (92). Scanning on the smooth core surface by XRF Core scanner is reliable and non-destructive to the sediment, requiring little or no time to prepare the core. This method overcomes the drawback of the traditional analytical method by ICP-AES or ICP-MS which requires long time for sample preparation. Thus, it makes it viable to reconstruct long and high-resolution elemental time series from sediment cores. We have performed relatively elemental concentration analyses on the deep sea sediment cores from ODP site 1143 (southern SCS) down to 190.77 mcd (meters composite depth) by XRF core scanner. The depth resolution of the scanning is 1 cm, equivalent to a time resolution of ~250 years. The age model is based on tuning the benthic foraminiferal d18O at Site 1143 to obliquity and precession (Tian et al., 2002) which indicates that the 190.77 meters long sediment spans the past 5 Myr. We compared the records between 99.5 and 136.46 mcd with the elemental records from the same site obtained by Philips PW 2400 X-ray spectrometer (Wehausen et al., online publication). Comparison reveals, regardless of the absolute changes of the elements, that the elemental records (Si, Ti, Al, Fe, Mn, Ca, K, P, Ba, Rb, Sr) obtained by two methods are nearly the same. Results show that the relative concentration variations of the productivity related elements such as Ba and Ca display distinctive glacial-interglacial cycles for the past 5 Myr. These productivity cycles recorded show one-on-one relationship with the glacial-interglacial cycles of the global ice volume change recorded in the benthic foraminiferal d18O. The glacial-interglacial cycles in productivity and global ice volume changes are consistent with each other not only in amplitude but also in secular variations. The benthic d18O implies the final formation of the northern hemisphere glaciation between ~2.5 Ma and ~3.3 Ma, as indicated by gradually increased values of d18O. During this period, both Ba and Ca show gradually increased values of relative concentration, indicating increased productivity which was probably caused by intensified East Asia summer monsoon. The close relationship of the productivity related elemental variations with benthic foraminiferal d18O reveals that the Plio-Pleistocene variations of the East Asian monsoon have been greatly dominated by global ice volume change. Although the elements related to terrigenous detrital matter composition of site 1143 such as Ti, Fe, As, Co and Ni display distinct glacial-interglacial cycles for the past 5 Myr, they display different patterns in secular variation with that of the benthic foraminiferal d18O. The mismatch indicates that besides northern hemisphere glaciation other multiple processes including changes in provenance and weathering intensity caused by monsoonal climate variability and sea level fluctuations could have affected the terrigenous detrital matter composition of site 1143.
A First Look at PCMH Implementation for Minority Veterans: Room for Improvement.
Hernandez, Susan E; Taylor, Leslie; Grembowski, David; Reid, Robert J; Wong, Edwin; Nelson, Karin M; Liu, Chuan-Fen; Fihn, Stephan D; Hebert, Paul L
2016-03-01
Implementation of Patient Aligned Care Teams (PACT), a patient-centered medical home model, has been inconsistent among the >900 primary care facilities in the Veterans Health Administration. Estimate if the degree of PACT implementation at a facility varied with the percentage of minority veteran patients at the facility. Cross-sectional, facility-level analysis of PACT implementation measures in 2012. Veterans Health Administration hospital-based and community-based primary care facilities. We used a previously validated PACT Implementation Progress Index (Pi) and its 8 domains: access, continuity of care, care coordination, comprehensiveness, self-management support, and patient-centered care and communication, shared decision-making domains, and team functioning. Facilities were categorized as low (<5.2%, n=208), medium (5.2%-25.8%, n=413), and high (>25.8%, n=206) percent minority based on the percent of their own veteran population. Most minority veterans received care in high minority (69%) and medium minority facilities (29%). In adjusted analyses, medium and high minority facilities scored 0.773 (P=0.009) and 0.930 (P=0.008) points lower on the Pi score relative to low minority facilities. Relative to low minority facilities, both medium and high minority facilities were less likely of having high Pi scores (≥2) and more likely of having low Pi scores (≤-2). Both medium and high minority facilities had the same 3 domain scores lower than low minority facilities (care coordination, comprehensiveness, and self-management). Overall PACT implementation varied with respect to the racial/ethnic composition of a facility, with medium and high minority facilities having a lower implementation scores.
Bioremediation of an iron-rich mine effluent by Lemna minor.
Teixeira, S; Vieira, M N; Espinha Marques, J; Pereira, R
2014-01-01
Contamination of water resources by mine effluents is a serious environmental problem. In a old coal mine, in the north of Portugal (São Pedro da Cova, Gondoma),forty years after the activity has ended, a neutral mine drainage, rich in iron (FE) it stills being produced and it is continuously released in local streams (Ribeiro de Murta e Rio Ferreira) and in surrounding lands. The species Lemna minor has been shown to be a good model for ecotoxicological studies and it also has the capacity to bioaccumulate metals. The work aimed test the potential of the species L. minor to remediate this mine effluent, through the bioaccumulation of Fe, under greenhouse experiments and, at the same time, evaluate the time required to the maximum removal of Fe. The results have shown that L. minor was able to grow and develop in the Fe-rich effluent and bioaccumulating this element. Throughout the 21 days of testing it was found that there was a meaningful increase in the biomass of L. minor both in the contaminated and in the non-contaminated waters. It was also found that bioaccumulation of Fe (iron) occurred mainly during the first 7 days of testing. It was found that L. minor has potential for the bioremediation of effluents rich in iron.
NASA Technical Reports Server (NTRS)
Piatek, Slawomir; Pryor, Carlton; Bristow, Paul; Olszewski, Edward W.; Harris, Hugh C.; Mateo, Mario; Minniti, Dante; Tinney, Christopher G.
2005-01-01
This article presents a measurement of the proper motion of the Ursa Minor dwarf spheroidal galaxy determined from images taken with the Hubble Space Telescope in two distinct fields. Each field contains a quasi-stellar object that serves as the "reference point". Integrating the motion of Ursa Minor in a realistic potential for the Milky Way produces orbital elements. The perigalacticon and apogalacticon are 40 (10, 76) and 89 (78, 160) kpc, respectively, where the values in the parentheses represent the 95% confidence intervals derived from Monte Carlo experiments. The eccentricity of the orbit is 0.39 (0.09, 0.79), and the orbital period is 1.5 (1.1, 2.7) Gyr. The orbit is retrograde and inclined by 124 degrees (94 deg, 36 deg ) to the Galactic plane. Ursa Minor is not a likely member of a proposed stream of galaxies on similar orbits around the Milky Way, nor is the plane of its orbit coincident with a recently proposed planar alignment of galaxies around the Milky Way. Comparing the orbits of Ursa Minor and Carina shows no reason for the different star formation histories of these two galaxies. Ursa Minor must contain dark matter to have a high probability of having survived disruption by the Galactic tidal force until the present.
Structural Evaluation of the RSRM Nozzle Replacement Adhesive
NASA Technical Reports Server (NTRS)
Batista-Rodriguez, A.; McLennan, M. L.; Palumbos, A. V.; Richardson, D. E.
1999-01-01
This paper describes the structural performance evaluation of a replacement adhesive for the Reusable Solid Rocket Motor (RSRM) nozzle utilizing finite element analysis. Due to material obsolescence and industrial safety issues, the two current structural adhesives, EA 913 and EA 946 are to be replaced with a new adhesive. TIGA 321. The structural evaluation in support of the adhesive replacement effort includes residual stress, transportation, and flight analyses. Factors of safety are calculated using the stress response from each analysis. The factors of safety are used as the limiting criteria to compare the replacement adhesive against the current adhesives. Included in this paper are the analytical approach, assumptions and modeling techniques as well as the results of the evaluation. An important factor to the evaluation is the similarity in constitutive material properties (elastic modulus and Poisson's ratio) between TIGA 321 and EA 913. This similarity leads to equivalent material response from the two adhesives. However, TIGA 321 surpasses EA 913's performance due to higher material capabilities. Conversely, the change in stress response from EA 946 to TIGA 321 is more apparent: this is primarily attributed to the difference in the modulii of the two adhesives, which differ by two orders of magnitude. The results of the bondline evaluation indicate that the replacement adhesive provides superior performance than the current adhesives with only minor exceptions. Furthermore, TIGA 321 causes only a minor chance in the response of the phenolic and metal components.
Design of a cluster-randomized minority recruitment trial: RECRUIT.
Tilley, Barbara C; Mainous, Arch G; Smith, Daniel W; McKee, M Diane; Amorrortu, Rossybelle P; Alvidrez, Jennifer; Diaz, Vanessa; Ford, Marvella E; Fernandez, Maria E; Hauser, Robert A; Singer, Carlos; Landa, Veronica; Trevino, Aron; DeSantis, Stacia M; Zhang, Yefei; Daniels, Elvan; Tabor, Derrick; Vernon, Sally W
2017-06-01
Racial/ethnic minority groups remain underrepresented in clinical trials. Many strategies to increase minority recruitment focus on minority communities and emphasize common diseases such as hypertension. Scant literature focuses on minority recruitment to trials of less common conditions, often conducted in specialty clinics and dependent on physician referrals. We identified trust/mistrust of specialist physician investigators and institutions conducting medical research and consequent participant reluctance to participate in clinical trials as key-shared barriers across racial/ethnic groups. We developed a trust-based continuous quality improvement intervention to build trust between specialist physician investigators and community minority-serving physicians and ultimately potential trial participants. To avoid the inherent biases of non-randomized studies, we evaluated the intervention in the national Randomized Recruitment Intervention Trial (RECRUIT). This report presents the design of RECRUIT. Specialty clinic follow-up continues through April 2017. We hypothesized that specialist physician investigators and coordinators trained in the trust-based continuous quality improvement intervention would enroll a greater proportion of minority participants in their specialty clinics than specialist physician investigators in control specialty clinics. Specialty clinic was the unit of randomization. Using continuous quality improvement, the specialist physician investigators and coordinators tailored recruitment approaches to their specialty clinic characteristics and populations. Primary analyses were adjusted for clustering by specialty clinic within parent trial and matching covariates. RECRUIT was implemented in four multi-site clinical trials (parent trials) supported by three National Institutes of Health institutes and included 50 associated specialty clinics from these parent trials. Using current data, we have 88% power or greater to detect a 0.15 or greater difference from the currently observed control proportion adjusting for clustering. We detected no differences in baseline matching criteria between intervention and control specialty clinics (all p values > 0.17). RECRUIT was the first multi-site randomized control trial to examine the effectiveness of a trust-based continuous quality improvement intervention to increase minority recruitment into clinical trials. RECRUIT's innovations included its focus on building trust between specialist investigators and minority-serving physicians, the use of continuous quality improvement to tailor the intervention to each specialty clinic's specific racial/ethnic populations and barriers to minority recruitment, and the use of specialty clinics from more than one parent multi-site trial to increase generalizability. The effectiveness of the RECRUIT intervention will be determined after the completion of trial data collection and planned analyses.
Sun, Shufang; Hoyt, William T; Brockberg, Dustin; Lam, Jaime; Tiwari, Dhriti
2016-11-01
Psychological services are culturally encapsulated for dominant cultural groups, and racial minorities underutilize treatment even though they suffer from more severe psychological distress. Sociocultural factors such as acculturation (one's adaptation into mainstream group) and enculturation (one's adherence to culture of heritage) are hypothesized to affect minorities' attitudes toward seeking psychological services. This meta-analysis examined 3 methods to assess acculturation/enculturation-unidimensional acculturation, bidimensional acculturation, and bidimensional enculturation as predictors of help-seeking attitudes (HSAs)-both positive and negative attitudes-among racial and ethnic minorities in 207 samples drawn from 111 research reports. The omnibus correlations between acculturation/enculturation variables and HSAs were quite small, but in the predicted direction. Moderator analyses suggested a more nuanced understanding of the association between bidimensional enculturation and positive HSAs: This association was significant (r = -.14 95% CI[-.18, -.09]) for Asians and Asian Americans, but very close to zero and nonsignificant for other racial minority groups (African Americans, Latino Americans, and others). In addition, the domain of acculturation/enculturation assessed was predictive of effect size, with enculturation measures containing a higher proportion of cognitive items (e.g., items that assess cultural values and beliefs) showing stronger (more negative) associations with positive HSAs. Post hoc analyses indicated that certain Asian cultural values, including emotional self-control, conformity to social norms, and collectivism, showed especially high negative associations with positive HSAs. (PsycINFO Database Record (c) 2016 APA, all rights reserved).
U.S. Issues Policy on Racial Harassment.
ERIC Educational Resources Information Center
Jaschik, Scott
1994-01-01
New federal Department of Education guidelines put responsibility for monitoring campus racial climate on individual colleges. The policy statement contains some elements pleasing to minority students and others attractive to civil libertarians. However, its broad definition of harassment is criticized by some. (MSE)
A disintegrating minor planet transiting a white dwarf.
Vanderburg, Andrew; Johnson, John Asher; Rappaport, Saul; Bieryla, Allyson; Irwin, Jonathan; Lewis, John Arban; Kipping, David; Brown, Warren R; Dufour, Patrick; Ciardi, David R; Angus, Ruth; Schaefer, Laura; Latham, David W; Charbonneau, David; Beichman, Charles; Eastman, Jason; McCrady, Nate; Wittenmyer, Robert A; Wright, Jason T
2015-10-22
Most stars become white dwarfs after they have exhausted their nuclear fuel (the Sun will be one such). Between one-quarter and one-half of white dwarfs have elements heavier than helium in their atmospheres, even though these elements ought to sink rapidly into the stellar interiors (unless they are occasionally replenished). The abundance ratios of heavy elements in the atmospheres of white dwarfs are similar to the ratios in rocky bodies in the Solar System. This fact, together with the existence of warm, dusty debris disks surrounding about four per cent of white dwarfs, suggests that rocky debris from the planetary systems of white-dwarf progenitors occasionally pollutes the atmospheres of the stars. The total accreted mass of this debris is sometimes comparable to the mass of large asteroids in the Solar System. However, rocky, disintegrating bodies around a white dwarf have not yet been observed. Here we report observations of a white dwarf--WD 1145+017--being transited by at least one, and probably several, disintegrating planetesimals, with periods ranging from 4.5 hours to 4.9 hours. The strongest transit signals occur every 4.5 hours and exhibit varying depths (blocking up to 40 per cent of the star's brightness) and asymmetric profiles, indicative of a small object with a cometary tail of dusty effluent material. The star has a dusty debris disk, and the star's spectrum shows prominent lines from heavy elements such as magnesium, aluminium, silicon, calcium, iron, and nickel. This system provides further evidence that the pollution of white dwarfs by heavy elements might originate from disrupted rocky bodies such as asteroids and minor planets.
Toumi, Mondher; Motrunich, Anastasiia; Millier, Aurélie; Rémuzat, Cécile; Chouaid, Christos; Falissard, Bruno; Aballéa, Samuel
2017-01-01
ABSTRACT Background: Despite the guidelines for Economic and Public Health Assessment Committee (CEESP) submission having been available for nearly six years, the dossiers submitted continue to deviate from them, potentially impacting product prices. Objective: to review the reports published by CEESP, analyse deviations from the guidelines, and discuss their implications for the pricing and reimbursement process. Study design: CEESP reports published until January 2017 were reviewed, and deviations from the guidelines were extracted. The frequency of deviations was described by type of methodological concern (minor, important or major). Results: In 19 reports, we identified 243 methodological concerns, most often concerning modelling, measurement and valuation of health states and results presentation and sensitivity analyses; nearly 63% were minor, 33% were important and 4.5% were major. All reports included minor methodological concerns, and 17 (89%) included at least one important and/or major methodological concern. Global major methodological concerns completely invalidated the analysis in seven dossiers (37%). Conclusion: The CEESP submission dossiers fail to adhere to the guidelines, potentially invalidating the health economics analysis and resulting in pricing negotiations. As these negotiations tend to be unfavourable for the manufacturer, the industry should strive to improve the quality of the analyses submitted to CEESP. PMID:28804600
The expression of APRIL in Sjogren's syndrome: aberrant expression of APRIL in the salivary gland.
Vosters, Jelle L; Roescher, Nienke; Polling, Eline J; Illei, Gabor G; Tak, Paul P
2012-09-01
A proliferation-inducing ligand (APRIL) and B-cell activating factor (BAFF) are B-cell-related mediators and may play a role in the pathogenesis in SS. In this descriptive study we assessed the expression of APRIL and BAFF in the minor salivary gland and serum from SS patients. Paraffin-embedded minor salivary gland sections from SS patients, non-SS controls and healthy volunteers were analysed by immunohistochemistry. Digital image quantification was performed to evaluate the expression of BAFF, APRIL and transmembrane activator and CAML interactor. Furthermore, serum was analysed for soluble BAFF and APRIL levels by ELISA. All the data were also analysed for subjects with decreased and normal stimulated salivary flow independent of the classification. APRIL expression was lower in minor salivary gland biopsies from SS patients compared with healthy volunteers and to a lesser extent non-SS controls, whereas BAFF expression was similar in all groups. Soluble APRIL levels in serum were increased in SS patients and in subjects with decreased salivary flow independent of the classification. APRIL salivary gland tissue levels are decreased, suggesting that targeting this cytokine locally in the salivary glands would not benefit SS patients. Moreover, the discrepancy between local and systemic levels is striking and future research should assess this in more detail.
NASA Astrophysics Data System (ADS)
Godard, M.; Bennett, E.; Carter, E.; Kourim, F.; Lafay, R.; Noël, J.; Kelemen, P. B.; Michibayashi, K.; Harris, M.
2017-12-01
The transition from the base of the Oman ophiolite to the underlying metamorphic sole was drilled at Hole BT1B (Sumail Massif) during Phase 1 of Oman Drilling Project (Winter 2016-2017). 74 samples were collected from the 300m of recovered cores for whole rock geochemical and XRD analyses. 55 listvenites, ophicarbonates and serpentinites, and 19 schists and greenstones were analyzed for major and minor elements (XRF) and for CO2 and S concentrations (CHNS) aboard DV Chikyu (ChikyuOman, Summer 2017). Analyses for trace elements (ICP-MS) at the University of Montpellier are in progress. The composition of listvenites, ophicalcites and serpentinites recovered at Hole BT1B record extensive interactions between CO2-rich fluids and the serpentinized peridotites. These reactions involved addition of SiO2 and formation of carbonates at the expense of the serpentinized peridotite protolith. All samples recovered from the mantle section are enriched in fluid mobile and incompatible trace elements compared to the mean composition of the Oman mantle. These enrichments are up to 103 times the Oman mantle for Rb and Ba. They mimic the pattern of the samples from the metamorphic sole. This suggests that the composition of the listvenites in these elements is controlled by that of contaminating fluids that may have originated in the same lithologies as those drilled at the base of Hole BT1B. Listvenites, ophicalcites and serpentinites also show notable downhole chemical variations, with listvenites showing marked variations in Al2O3 and TiO2. Occurrence of lherzolites and cpx-harzburgites has been reported at the base of the Oman dominantly harzburgitic mantle section. The observed variations in the listvenites (Al2O3 and TiO2) could be related to the composition of their protolith, the deepest having more fertile compositions. Alternatively, the observed downhole changes in the composition of listvenites may relate to the progressive equilibration of the reacting ultramafic-rocks and/or listvenite with the fluids originating in the subducting metamorphic sole; these variations could be related to heterogeneous reaction kinetics (temperature, reactive surfaces, chemical gradients) and/or to transport (e.g. local variations in permeability) within the listvenite units.
NASA Astrophysics Data System (ADS)
Somasekhar, V.; Ramanaiah, S.; Sarma, D. Srinivasa
2018-06-01
Petrological and geochemical studies have been carried out on Pulivendla and Gandikota Quartzite from Chitravati Group of Cuddapah Supergroup to decipher the provenance and depositional environment. Both the units are texturally mature with sub-rounded to well-rounded and moderately to well-sorted grains. Majority of the framework grains are quartz, in the form of monocrystalline quartz, followed by feldspars (K-feldspar and plagioclase), mica, rock fragments, heavy minerals, with minor proportion of the matrix and cement. Based on major element geochemical classification diagram, Pulivendla Quartzite is considered as quartz-arenite and arkose to sub-arkose, whereas Gandikota Quartzite falls in the field of lith-arenite and arkose to sub-arkose. Weathering indices like CIA, PIA, CIW, ICV, Th/U ratio and A-CN-K ternary diagram suggest moderate to intense chemical weathering of the source rocks of these quartzites. Whole rock geochemistry of quartzites indicate that they are primarily from the first-cycle sediments, along with some minor recycled components. Also their sources were mostly intermediate-felsic igneous rocks of Archean age. The tectonic discrimination plots, Th-Sc-Zr/10 of both these formations reflect active to passive continental margin setting. Chondrite-normalized rare earth element (REE) patterns, and various trace element ratios like Cr/Th, Th/Co, La/Sc and Th/Cr indicate dominantly felsic source with minor contribution from mafic source. Th/Sc ratios of Pulivendla and Gandikota Quartzite are in close proximity with average values of 2.83, 3.45 respectively, which is higher than AUCC (Th/Sc=0.97), demonstrating that the contributions from more alkali source rocks than those that contributed to AUCC.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Campbell, Keri; Judge, Elizabeth J.; Dirmyer, Matthew R.
Surrogate nuclear explosive debris was synthesized and characterized for major, minor, and trace elemental composition as well as uranium isotopics. The samples consisted of an urban glass matrix, equal masses soda lime and cement, doped with 500 ppm uranium with varying enrichments. The surface and cross section morphology were measured with SEM, and the major elemental composition was determined by XPS. LA-ICP-MS was used to measure the uranium isotopic abundance comparing different sampling techniques. Furthermore, the results provide an example of the utility of LA-ICP-MS for forensics applications.
In vivo evaluation of a magnesium-based degradable intramedullary nailing system in a sheep model.
Rössig, Christina; Angrisani, Nina; Helmecke, Patrick; Besdo, Silke; Seitz, Jan-Marten; Welke, Bastian; Fedchenko, Nickolay; Kock, Heiko; Reifenrath, Janin
2015-10-01
The biocompatibility and the degradation behavior of the LAE442 magnesium-based intramedullary interlocked nailing system (IM-NS) was assessed in vivo in a comparative study (stainless austenitic steel 1.4441LA) for the first time. IM-NS was implanted into the right tibia (24-week investigation period; nails/screws diameter: 9 mm/3.5 mm, length: 130 mm/15-40 mm) of 10 adult sheep (LAE442, stainless steel, n=5 each group). Clinical and radiographic examinations, in vivo computed tomography (CT), ex vivo micro-computed tomography (μCT), mechanical and histological examinations and element analyses of alloying elements in inner organs were performed. The mechanical examinations (four-point bending) revealed a significant decrease of LAE442 implant stiffness, force at 0.2% offset yield point and maximum force. Periosteal (new bone formation) and endosteal (bone decline) located bone alterations occurred in both groups (LAE442 alloy more pronounced). Moderate gas formation was observed within the LAE442 alloy group. The CT-measured implant volume decreased slightly (not significant). Histologically a predominantly direct bone-to-implant interface existed within the LAE442 alloy group. Formation of a fibrous tissue capsule around the nail occurred in the steel group. Minor inflammatory infiltration was observed in the LAE442 alloy group. Significantly increased quantities of rare earth elements were detected in the LAE442 alloy group. μCT examination showed the beginning of corrosion in dependence of the surrounding tissue. After 24 weeks the local biocompatibility of LAE442 can be considered as suitable for a degradable implant material. An application oriented interlocked intramedullary nailing system in a comparative study (degradable magnesium-based LAE442 alloy vs. steel alloy) was examined in a sheep model for the first time. We focused in particular on the examination of implant degradation by means of (μ-)CT, mechanical properties (four-point bending), clinical compatibility, local bone reactions (X-ray and histology) and possible systemic toxicity (histology and element analyses of inner organs). A significant decrease of magnesium (LAE442 alloy) implant stiffness and maximum force occurred. Moderate not clinically relevant gas accumulation was determined. A predominantly direct bone-to-implant contact existed within the magnesium (LAE442 alloy) group compared to an indirect contact in the steel group. Rare earth element accumulation could be observed in inner organs but H&E staining was inconspicuous. Copyright © 2015 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
NASA Technical Reports Server (NTRS)
Winzer, S. R.; Meyerhoff, M.; Nava, D. F.; Schuhmann, S.; Philpotts, J. A.; Lindstrom, D. J.; Lum, R. K. L.; Lindstrom, M. M.; Schuhmann, P.
1977-01-01
The matrix and 58 clasts from breccia 61175 were analyzed for major, minor, and trace elements. The matrix is anorthositic and has lithophile trace element abundances 20 to 40 times chondrite. Clasts comprise impact melt rocks, xenocryst and xenolith-free very high aluminum (VHA) and anorthositic basalts, anorthosite, anorthosite-norite-troctolite granulites, and hornfelses. The VHA and anorthositic basalts are considered to be impact melts, and the hornfelses were probably formed by incorporation of breccias or preexisting melt rocks into a melt sheet prior to cooling. The range of melt-rock lithophile trace element abundances might indicate more than one melt sheet.
The petrogenesis of L-6 chondrites - Insights from the chemistry of minerals
NASA Technical Reports Server (NTRS)
Curtis, D. B.; Schmitt, R. A.
1979-01-01
Measurements of the major, minor and trace element abundances of the major minerals of the L-6 chondrites Alfianello, Colby (WI) and Leedey are used to investigate the formation mechanisms of L-6 chondrites. Electron microprobe analysis was performed on individual grains of each mineral, and separated minerals were analyzed by instrumental and radiochemical neutron activation analysis. The compositions of the three meteorites are observed to be generally uniform, however different abundances and distributions of rare earth elements and Co and Ni indicate that the meteorites have different petrogenetic histories. Alkali element distributions are found to be incompatible with internal equilibration of a closed system.
ERIC Educational Resources Information Center
Qian, Xiaoyu; Nandakumar, Ratna; Glutting, Joseoph; Ford, Danielle; Fifield, Steve
2017-01-01
In this study, we investigated gender and minority achievement gaps on 8th-grade science items employing a multilevel item response methodology. Both gaps were wider on physics and earth science items than on biology and chemistry items. Larger gender gaps were found on items with specific topics favoring male students than other items, for…
Hilal, Saima; Kuijf, Hugo J.; Ikram, Mohammad Kamran; Xu, Xin; Tan, Boon Yeow; Venketasubramanian, Narayanaswamy; Postma, Albert; Biessels, Geert Jan; Chen, Christopher P. L. H.
2016-01-01
Background and Purpose Studies on the impact of small vessel disease (SVD) on cognition generally focus on white matter hyperintensity (WMH) volume. The extent to which WMH location relates to cognitive performance has received less attention, but is likely to be functionally important. We examined the relation between WMH location and cognition in a memory clinic cohort of patients with sporadic SVD. Methods A total of 167 patients with SVD were recruited from memory clinics. Assumption-free region of interest-based analyses based on major white matter tracts and voxel-wise analyses were used to determine the association between WMH location and executive functioning, visuomotor speed and memory. Results Region of interest-based analyses showed that WMHs located particularly within the anterior thalamic radiation and forceps minor were inversely associated with both executive functioning and visuomotor speed, independent of total WMH volume. Memory was significantly associated with WMH volume in the forceps minor, independent of total WMH volume. An independent assumption-free voxel-wise analysis identified strategic voxels in these same tracts. Region of interest-based analyses showed that WMH volume within the anterior thalamic radiation explained 6.8% of variance in executive functioning, compared to 3.9% for total WMH volume; WMH volume within the forceps minor explained 4.6% of variance in visuomotor speed and 4.2% of variance in memory, compared to 1.8% and 1.3% respectively for total WMH volume. Conclusions Our findings identify the anterior thalamic radiation and forceps minor as strategic white matter tracts in which WMHs are most strongly associated with cognitive impairment in memory clinic patients with SVD. WMH volumes in individual tracts explained more variance in cognition than total WMH burden, emphasizing the importance of lesion location when addressing the functional consequences of WMHs. PMID:27824925
NASA Astrophysics Data System (ADS)
Seitz, Hans-Michael; Brey, Gerhard P.; Harris, Jeffrey W.; Durali-Müller, Soodabeh; Ludwig, Thomas; Höfer, Heidi E.
2018-05-01
The most remarkable feature of the inclusion suite in ultradeep alluvial and kimberlitic diamonds from Sao Luiz (Juina area in Brazil) is the enormous range in Mg# [100xMg/(Mg + Fe)] of the ferropericlases (fper). The Mg-richer ferropericlases are from the boundary to the lower mantle or from the lower mantle itself when they coexist with ringwoodite or Mg- perovskite (bridgmanite). This, however, is not an explanation for the more Fe-rich members and a lowermost mantle or a "D" layer origin has been proposed for them. Such a suggested ultra-deep origin separates the Fe-rich fper-bearing diamonds from the rest of the Sao Luiz ultradeep diamond inclusion suite, which also contains Ca-rich phases. These are now thought to have an origin in the uppermost lower mantle and in the transition zone and to belong either to a peridotitic or mafic (subducted oceanic crust) protolith lithology. We analysed a new set of more Fe-rich ferropericlase inclusions from 10 Sao Luiz ultradeep alluvial diamonds for their Li isotope composition by solution MC-ICP-MS (multi collector inductively coupled plasma mass spectrometry), their major and minor elements by EPMA (electron probe micro-analyser) and their Li-contents by SIMS (secondary ion mass spectrometry), with the aim to understand the origin of the ferropericlase protoliths. Our new data confirm the wide range of ferropericlase Mg# that were reported before and augment the known lack of correlation between major and minor elements. Four pooled ferropericlase inclusions from four diamonds provided sufficient material to determine for the first time their Li isotope composition, which ranges from δ7Li + 9.6 ‰ to -3.9 ‰. This wide Li isotopic range encompasses that of serpentinized ocean floor peridotites including rodingites and ophicarbonates, fresh and altered MORB (mid ocean ridge basalt), seafloor sediments and of eclogites. This large range in Li isotopic composition, up to 5 times higher than `primitive upper mantle' Li-abundances, and an extremely large and incoherent range in Mg# and Cr, Ni, Mn, Na contents in the ferropericlase inclusions suggests that their protoliths were members of the above lithologies. This mélange of altered rocks originally contained a variety of carbonates (calcite, magnesite, dolomite, siderite) and brucite as the secondary products in veins and as patches and Ca-rich members like rodingites and ophicarbonates. Dehydration and redox reactions during or after deep subduction into the transition zone and the upper parts of the lower mantle led to the formation of diamond and ferropericlase inclusions with variable compositions and a predominance of the Ca-rich, high-pressure silicate inclusions. We suggest that the latter originated from peridotites, mafic rocks and sedimentary rocks as redox products between calcite and SiO2.
Storm, Ingrid; Sobolewska, Maria; Ford, Robert
2017-09-01
Most literature on racial prejudice deals with the racial attitudes of the ethnic majority and ethnic minorities separately. This paper breaks this tradition. We examine the social distance attitudes of white and non-white British residents to test if these attitudes follow the same trends over time, whether they are driven by the same social processes and whether they are inter-related. We have three main findings. Firstly, social distance from other ethnic groups has declined over time for both white and ethnic minority Britons. For the white majority there are both period and cohort elements to this decline. Secondly, we see some evidence that social distance between the majority and minority groups is reciprocal. Specifically, minorities who experience rejection by the white British feel a greater sense of distance from them. Thirdly, we find that all groups share the perception of the same ethnic hierarchy. We see evidence of particularly widespread hostility towards Muslim Britons from all ethnic groups suggesting that Muslims are singled out for negative attention from many British residents of all other backgrounds, including a large number who do not express hostility to other groups. © London School of Economics and Political Science 2017.
Trace-element analyses of core samples from the 1967-1988 drillings of Kilauea Iki lava lake, Hawaii
Helz, Rosalind Tuthill
2012-01-01
This report presents previously unpublished analyses of trace elements in drill core samples from Kilauea Iki lava lake and from the 1959 eruption that fed the lava lake. The two types of data presented were obtained by instrumental neutron-activation analysis (INAA) and energy-dispersive X-ray fluorescence analysis (EDXRF). The analyses were performed in U.S. Geological Survey (USGS) laboratories from 1989 to 1994. This report contains 93 INAA analyses on 84 samples and 68 EDXRF analyses on 68 samples. The purpose of the study was to document trace-element variation during chemical differentiation, especially during the closed-system differentiation of Kilauea Iki lava lake.
Steuerwald, Amy J.; Parsons, Patrick J.; Arnason, John G.; Chen, Zhen; Peterson, C. Matthew; Louis, Germaine M. Buck
2013-01-01
Analysis of human urine is commonly used in biomonitoring studies to assess exposure to essential (e.g., Cu, Zn, Se) and non-essential (Pb, Cd, Pt) trace elements. These data are also used in epidemiological studies to evaluate potential associations between trace element exposure and various health outcomes within a population. Today most trace element analyses are typically performed using quadrupole-based inductively coupled plasma mass spectrometry (Q-ICP-MS). However, there is always the potential for spectral interferences with Q-ICP-MS instrumentation, especially when analyzing human specimens that may contain medications and other exogenous substances. Moreover, such xenobiotics may be unknown to the investigators. In a recent study focusing on environmental exposures and endometriosis: Endometriosis: Natural History, Diagnosis, and Outcomes (ENDO Study), urine specimens (n=619) were collected from participating women upon enrollment into the study or prior to surgery or pelvic magnetic resonance imaging (MRI), and analyzed for 21 trace elements by Q-ICP-MS. Here we report on some anomalous results observed for Se and Pt with elevated concentrations up to several orders of magnitude greater than what might be expected based on established reference intervals. Further investigations using Sector Field (SF-) ICP-MS instrumentation led to identification of doubly charged and polyatomic gadolinium (Gd) species traced to a Gd-based contrast agent that was administered to some subjects just prior to urine collection. Specifically, interferences from Gd2+ and several minor polyatomics were identified as interferences on all of the major isotopes of Se including 74Se, 76Se, 77Se, 78Se, 80Se, and 82Se. While trace amounts of Pt were present in the urine, a number of Gd-containing polyatomic species were also evident as major interferences on all isotopes of Pt (190Pt, 192Pt, 194Pt, 195Pt, 196Pt, and 198Pt), including Gd-chlorides, Gd-argides, and Gd-oxides. These observations underscore the importance of considering potential isobaric interferences when interpreting unusual trace element results for clinical specimens. PMID:27397951
Petrology of the axial ridge of the Mariana Trough backarc spreading center
NASA Astrophysics Data System (ADS)
Hawkins, J. W.; Lonsdale, P. F.; Macdougall, J. D.; Volpe, A. M.
1990-10-01
The axial ridge of the Mariana Trough backarc basin, between 17°40'N and 18°30'N rises as much as 1 km above the floor of a 10-15 km wide rift valley. Physiographic segmentation, with minor ridge offsets and overlaps, coincides with a petrologic segmentation seen in trace element and isotope chemistry. Analyses of 239 glass and 40 aphyric basalt samples, collected with ALVIN and by dredging, show that the axial ridge is formed largely of (olivine) hypersthene-normative tholeiitic basalt. About half of these are enriched in both LIL elements and volatiles, but are depleted in HFS elements like other rocks found throughout much of the Mariana Trough. The LIL enrichments distinguish these rocks from N-MORB even though Nd and Sr isotope ratios indicate that much of the crust formed from a source similar to that for N-MORB. In addition to LIL-enriched basalt there is LIL depleted basalts even more closely resembling N-MORB in major and trace elements as well as Sr, Nd and Pb isotopes. Both basalt varieties have higher Al and lower total Fe than MORB at equivalent Mg level. Mg# ranges from relatively "primitive" (e.g. Mg# 65-70) to more highly fractionated (e.g. Mg# 45-50). Highest parts of the axial ridge are capped by pinnacles with elongated pillows of basaltic andesite (e.g. 52-56%) SiO 2. These are due to extreme fractional crystallization of basalts forming the axial ridge. Active hydrothermal vents with chimneys and mats of opaline silica, barite, sphalerite and lesser amounts of pyrite, chalcopyrite and galena formed near these silicic rocks. The vents are surrounded by distinctive vent animals, polychaete worms, crabs and barnacles. Isotope data indicate that the Mariana Trough crust was derived from a heterogeneous source including mantle resembling the MORB-source and an "arc-source" component. The latter was depleted in HFS elements in previous melting events and later modified by addition of H 2O and LIL elements.
ERIC Educational Resources Information Center
Henrichs, Erinn L.; Jackson, Julie K.
2012-01-01
Establishing classroom routines that provide students with the opportunities to learn and successfully apply the language of science is a daunting task. With minor variations, research has shown that effective and comprehensive vocabulary programs share four common elements: they are rich and varied language experiences; they teach well-selected…
Drug Education: Reasons and Failures
ERIC Educational Resources Information Center
Smith, Cameron V.
1971-01-01
This paper contains 50 reasons" used to explain increasing drug abuse by youth, grouped into 10 categories: criminal elements, minorities, youth, adults, homes, schools, churches, corporate system, political system, and society. The interplay of reasons is extremely complicated; hence educational or remedial programs built upon simplistic cause…
Publications - RDF 2002-1 | Alaska Division of Geological & Geophysical
., Clautice, K.H., Flynn, R.L., Grady, J.C., Munly, W.C., and Johnson, M.R. Publication Date: Aug 2002 ., Flynn, R.L., Grady, J.C., Munly, W.C., and Johnson, M.R., 2002, Major-oxide, minor-oxide, trace-element
NASA Astrophysics Data System (ADS)
Zhong, Xin; Frehner, Marcel; Kunze, Karsten; Zappone, Alba
2014-10-01
A novel electron backscatter diffraction (EBSD) -based finite-element (FE) wave propagation simulation is presented and applied to investigate seismic anisotropy of peridotite samples. The FE model simulates the dynamic propagation of seismic waves along any chosen direction through representative 2D EBSD sections. The numerical model allows separation of the effects of crystallographic preferred orientation (CPO) and shape preferred orientation (SPO). The obtained seismic velocities with respect to specimen orientation are compared with Voigt-Reuss-Hill estimates and with laboratory measurements. The results of these three independent methods testify that CPO is the dominant factor controlling seismic anisotropy. Fracture fillings and minor minerals like hornblende only influence the seismic anisotropy if their volume proportion is sufficiently large (up to 23%). The SPO influence is minor compared to the other factors. The presented FE model is discussed with regard to its potential in simulating seismic wave propagation using EBSD data representing natural rock petrofabrics.
Satam, Vijay; Babu, Balaji; Patil, Pravin; Brien, Kimberly A; Olson, Kevin; Savagian, Mia; Lee, Megan; Mepham, Andrew; Jobe, Laura Beth; Bingham, John P; Pett, Luke; Wang, Shuo; Ferrara, Maddi; Bruce, Chrystal D; Wilson, W David; Lee, Moses; Hartley, John A; Kiakos, Konstantinos
2015-09-01
The design, synthesis, and DNA binding properties of azaHx-PI or p-anisyl-4-aza-benzimidazole-pyrrole-imidazole (5) are described. AzaHx, 2-(p-anisyl)-4-aza-benzimidazole-5-carboxamide, is a novel, fluorescent DNA recognition element, derived from Hoechst 33258 to recognize G·C base pairs. Supported by theoretical data, the results from DNase I footprinting, CD, ΔT(M), and SPR studies provided evidence that an azaHx/IP pairing, formed from antiparallel stacking of two azaHx-PI molecules in a side-by-side manner in the minor groove, selectively recognized a C-G doublet. AzaHx-PI was found to target 5'-ACGCGT-3', the Mlu1 Cell Cycle Box (MCB) promoter sequence with specificity and significant affinity (K(eq) 4.0±0.2×10(7) M(-1)). Copyright © 2015 Elsevier Ltd. All rights reserved.
Silvey, W.D.; Brennan, R.
1962-01-01
A method for the quantitative spectrochemical determination of microgram amounts of 17 minor elements in water is given. The chelating reagents 8-quinolinol, tannic acid, and thionalide are utilized to concentrate traces (1 to 500 ??g.) of aluminum, cobalt, chromium, copper, iron, gallium, germanium, manganese, nickel, titanium, vanadium, bismuth, lead, molybdenum, cadmium, zinc, and beryllium. Indium is added as a buffer, and palladium is used as an internal standard. The ashed oxides of these 17 metals are subsequently subjected to direct current arcing conditions during spectrum analysis. The method can be used to analyze waters with dissolved solids ranging from less than 100 to more than 100,000 p.p.m. There is no limiting concentration range for the determination of the heavy metals since any volume of sample can be used that will contain a heavy metal concentration within the analytical range of the method. Both the chemical and spectrographic procedures are described, and precision and accuracy data are given.
Stress and efficiency studies in EFG
NASA Technical Reports Server (NTRS)
1986-01-01
The goals of this program were: (1) to define minimum stress configurations for silicon sheet growth at high speeds; (2) to quantify dislocation electrical activity and their limits on minority carrier diffusion length in deformed silicon; and (3) to study reasons for degradation of lifetime with increases in doping level in edge-defined film-fed growth (EFG) materials. A finite element model was developed for calculating residual stress with plastic deformation. A finite element model was verified for EFG control variable relationships to temperature field of the sheet to permit prediction of profiles and stresses encountered in EFG systems. A residual stress measurement technique was developed for finite size EFG material blanks using shadow Moire interferometry. Transient creep response of silicon was investigated in the temperature range between 800 and 1400 C in strain and strain regimes of interest in stress analysis of sheet growth. Quantitative relationships were established between minority carrier diffusion length and dislocation densities using Electron Beam Induced Current (EBIC) measurement in FZ silicon deformed in four point bending tests.
van Os, E C C; Kalverboer, M E; Zijlstra, A E; Post, W J; Knorth, E J
2016-09-01
Decision-making regarding an asylum request of a minor requires decision-makers to determine the best interests of the child when the minor is relatively unknown. This article presents a systematic review of the existing knowledge of the situation of recently arrived refugee children in the host country. This research is based on the General Comment No. 14 of UN Committee on the Rights of the Child. It shows the importance of knowing the type and number of stressful life events a refugee child has experienced before arrival, as well as the duration and severity of these events. The most common mental health problems children face upon arrival in the host country are PTSD, depression and various anxiety disorders. The results identify the relevant elements of the best interests of the child assessment, including implications for procedural safeguards, which should promote a child rights-based decision in the asylum procedure.
NASA Technical Reports Server (NTRS)
Parr, R. A.; Johnston, M. H.; Mcclure, J. C.
1980-01-01
Monotectic alloys having aligned spherical particles of rods of the minor component dispersed in a matrix of the major component are prepared by forming a melt containing predetermined amounts of the major and minor components of a chosen monotectic system, providing in the melt a dopant capable of breaking down the liquid solid interface for the chosen alloy, and directionally solidfying the melt at a selected temperature gradient and a selected rate of movement of the liquid-solid interface (growth rate). Shaping of the minor component into spheres or rods and the spacing between them are controlled by the amount of dopant and the temperature gradient and growth rate values. Specific alloy systems include Al Bi, Al Pb and Zn Bi, using a transition element such as iron.
Impact of Including Higher Actinides in Fast Reactor Transmutation Analyses
DOE Office of Scientific and Technical Information (OSTI.GOV)
B. Forget; M. Asgari; R. Ferrer
2007-09-01
Previous fast reactor transmutation studies generally disregarded higher mass minor actinides beyond Cm-246 due to various considerations including deficiencies in nuclear cross-section data. Although omission of these higher mass actinides does not significantly impact the neutronic calculations and fuel cycle performance parameters follow-on neutron dose calculations related to fuel recycling, transportation and handling are significantly impacted. This report shows that including the minor actinides in the equilibrium fast reactor calculations will increase the predicted neutron emission by about 30%. In addition a sensitivity study was initiated by comparing the impact of different cross-section evaluation file for representing these minor actinides.
Dózsa-Farkas, Klára; Csitári, Bianka; Felföldi, Tamás
2017-04-18
Results of a comparative investigation on five Cernosvitoviella species from Hungarian Sphagnum mires including their distribution and the description of a new species, Cernosvitoviella farkasi sp. n., are presented in this paper. Cernosvitoviella atrata, C. aggtelekiensis, C. crassoductus and C. farkasi sp. n. could be easily distinguished from each other based on both morphological and molecular taxonomic analyses. However, C. minor seems to be a species complex on the basis of these investigations, so it was referred as C. minor sensu lato. The status of the C. minor variants requires further studies.
Scandinavian guidelines for initial management of minor and moderate head trauma in children.
Astrand, Ramona; Rosenlund, Christina; Undén, Johan
2016-02-18
The management of minor and moderate head trauma in children differs widely between countries. Presently, there are no existing guidelines for management of these children in Scandinavia. The purpose of this study was to produce new evidence-based guidelines for the initial management of head trauma in the paediatric population in Scandinavia. The primary aim was to detect all children in need of neurosurgical intervention. Detection of any traumatic intracranial injury on CT scan was an important secondary aim. General methodology according to the Appraisal of Guidelines for Research and Evaluation (AGREE) II and the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system was used. Systematic evidence-based review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) methodology and based upon relevant clinical questions with respect to patient-important outcomes. Quality ratings of the included studies were performed using Quality Assessment of Diagnostic Accuracy Studies (QUADAS)-2 and Centre of Evidence Based Medicine (CEBM)-2 tools. Based upon the results, GRADE recommendations, a guideline, discharge instructions and in-hospital observation instructions were drafted. For elements with low evidence, a modified Delphi process was used for consensus, which included relevant clinical stakeholders. The guidelines include criteria for selecting children for CT scans, in-hospital observation or early discharge, and suggestions for monitoring routines and discharge advice for children and guardians. The guidelines separate mild head trauma patients into high-, medium- and low-risk categories, favouring observation for mild, low-risk patients as an attempt to reduce CT scans in children. We present new evidence and consensus based Scandinavian Neurotrauma Committee guidelines for initial management of minor and moderate head trauma in children. These guidelines should be validated before extensive clinical use and updated within four years due to rapid development of new diagnostic tools within paediatric neurotrauma.
Lyons, P.C.; Palmer, C.A.; Bostick, N.H.; Fletcher, J.D.; Dulong, F.T.; Brown, F.W.; Brown, Z.A.; Krasnow, M.R.; Romankiw, L.A.
1989-01-01
A rank series consisting of twelve vitrinite concentrates and companion whole-coal samples from mined coal beds in the eastern United States, England, and Australia were analyzed for C, H, N, O, ash, and 47 trace and minor elements by standard elemental, instrumental neutron activation analysis (INAA), and direct-current-arc spectrographic (DCAS) techniques. The reflectance of vitrinite, atomic H:C and O:C, and ash-free carbon data were used to determine ranks that range from high-volatile C bituminous coal to meta-anthracite. A van Krevelen (atomic H:C vs. O:C) diagram of the vitrinite concentrates shows a smooth curve having its lowest point at H:C = 0.18 and O:C = 0.01. This improves the van Krevelen diagram by the addition of our vitrinite concentrate from meta-anthracite from the Narragansett basin of New England. Boron content (400-450 ppm) in two Illinois basin vitrinite concentrates was about an order of magnitude higher than B contents in other concentrates analyzed. We attribute this to marine origin or hydrothermal activity. The alkaline-earth elements Ca, Mg and Ba (DCAS) have higher concentrations in our vitrinite concentrates from bituminous coals of the Appalachian basin, than they do in vitrinite concentrates from the marine-roofed bituminous coals of the Illinois basin; therefore, a nonmarine origin for these alkaline-earth elements is postulated for the Appalachian basin coals. An ion-exchange mechanism due to high concentrations of these elements as ions in diagenetic water, but probably not recent ground water, may be responsible for the relatively high values of these elements in Appalachian concentrates. Higher concentrations of Ni and Cr in one of the English vitrinite concentrates and of Zr in the Australian concentrate probably indicate organic association and detrital influence, respectively. ?? 1989.
Tucker, Raymond P; Testa, Rylan J; Reger, Mark A; Simpson, Tracy L; Shipherd, Jillian C; Lehavot, Keren
2018-01-12
Research suggests the prevalence of suicide ideation and suicide attempts in the transgender veteran community may be upwards of 20 times higher than nontransgender veterans, who are known to be at increased risk than the general US population. This study aimed to understand the potential influence of external and internal minority stress experienced during and after military service on past-year and recent suicide ideation in a sample of 201 transgender veterans. Nonparametric bootstrapping analyses indicated past-year transgender-specific discrimination and rejection (external minority stress) indirectly predicted frequency of both past-year and past 2-week suicide ideation through past-year shame related to gender identity (internal minority stress). This result was significant when controlling for symptoms of depression and demographics. Similar patterns emerged when examining relationships among military external and internal minority stress on suicide outcomes. These results suggest that attempts to reduce both the experience and impact of minority stressors related to gender identity during and after military service may be an important avenue for suicide prevention. © 2018 The American Association of Suicidology.
Parental consent for abortion and the judicial bypass option in Arkansas: effects and correlates.
Joyce, Ted
2010-09-01
In 2005, Arkansas changed its parental notification requirement for minors seeking an abortion to a parental consent law, under which a minor can obtain an abortion without consent after obtaining a judicial waiver. Using state health department data on 7,463 abortions among 15-19-year-olds over the period 2001-2007, an analysis of abortion and second-trimester abortion rates among Arkansas minors relative to rates among older teenagers evaluated the influence of the 2005 change in the law. Linear and logistic regression analyses estimated the changes in rates among different age-groups, and assessed the likelihood of minors' using the bypass procedure or having a second-trimester abortion. No association was found between the change in the law and either the abortion rate or the second-trimester abortion rate among minors in the state. Ten percent of all abortions among minors were obtained through the judicial bypass procedure, and minors aged 15 or younger who had an abortion were less likely than those aged 17 to get a waiver (odds ratio, 0.2). Minors who used the bypass option were less likely than those who obtained parental consent to have a second-trimester abortion (0.5), and they terminated the pregnancy 1.1 weeks earlier, on average, than did minors who had gotten such consent. States that convert a parental notification statute to a parental consent statute are unlikely to experience a decrease in abortions among minors. Copyright © 2010 by the Guttmacher Institute.
Discrimination, Mental Health, and Substance Use Disorders Among Sexual Minority Populations.
Lee, Ji Hyun; Gamarel, Kristi E; Bryant, Kendall J; Zaller, Nickolas D; Operario, Don
2016-08-01
Sexual minority (lesbian, gay, bisexual) populations have a higher prevalence of mental health and substance use disorders compared to their heterosexual counterparts. Such disparities have been attributed, in part, to minority stressors, including distal stressors such as discrimination. However, few studies have examined associations between discrimination, mental health, and substance use disorders by gender among sexual minority populations. We analyzed data from 577 adult men and women who self-identified as lesbian, gay, or bisexual and participated in Wave 2 of the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC). Six questions assessed discrimination due to sexual orientation. Weighted multivariable logistic regression examined associations between experiences of sexual orientation discrimination and both mental health and substance use disorders. Analyses were conducted separately for sexual minority men and women, adjusting for sociodemographic covariates. Sexual minority men who ever experienced discrimination (57.4%) reported higher odds of any lifetime drug use disorder and cannabis use disorder compared to sexual minority men who never experienced discrimination. Sexual minority women who ever experienced discrimination (42.9%) reported higher odds of any lifetime mood disorder and any lifetime anxiety disorder compared to sexual minority women who never experienced discrimination. The findings suggest that discrimination is differentially associated with internalizing (mental health) and externalizing (substance use) disorders for sexual minority men and women. These findings indicate a need to consider how homophobia and heteronormative discrimination may contribute to distinct health outcomes for lesbian and bisexual women compared with gay and bisexual men.
Yoo, Hyung Chol; Miller, Matthew J; Yip, Pansy
2015-04-01
There is limited research examining psychological correlates of a uniquely racialized experience of the model minority stereotype faced by Asian Americans. The present study examined the factor structure and fit of the only published measure of the internalization of the model minority myth, the Internalization of the Model Minority Myth Measure (IM-4; Yoo et al., 2010), with a sample of 155 Asian American high school adolescents. We also examined the link between internalization of the model minority myth types (i.e., myth associated with achievement and myth associated with unrestricted mobility) and psychological adjustment (i.e., affective distress, somatic distress, performance difficulty, academic expectations stress), and the potential moderating effect of academic performance (cumulative grade point average). Results suggested the 2-factor model of the IM-4 had an acceptable fit to the data and supported the factor structure using confirmatory factor analyses. Internalizing the model minority myth of achievement related positively to academic expectations stress; however, internalizing the model minority myth of unrestricted mobility related negatively to academic expectations stress, both controlling for gender and academic performance. Finally, academic performance moderated the model minority myth associated with unrestricted mobility and affective distress link and the model minority myth associated with achievement and performance difficulty link. These findings highlight the complex ways in which the model minority myth relates to psychological outcomes. (c) 2015 APA, all rights reserved).
Adams, David T.; Nielsen, Roger L.; Kent, Adam J.R.; Tepley, Frank J.
2011-01-01
Melt inclusions trapped in phenocryst phases are important primarily due to their potential of preserving a significant proportion of the diversity of magma composition prior to modification of the parent magma array during transport through the crust. The goal of this investigation was to evaluate the impact of formational and post-entrapment processes on the composition of melt inclusions hosted in high anorthite plagioclase in MORB. Our observations from three plagioclase ultra-phyric lavas from the Endeavor Segment of the Juan de Fuca Ridge document a narrow range of major elements and a dramatically greater range of minor and trace elements within most host plagioclase crystals. Observed host/inclusion partition coefficients for Ti are consistent with experimental determinations. In addition, observed values of DTi are independent of inclusion size and inclusion TiO2 content of the melt inclusion. These observations preclude significant effects from the re-homogenization process, entrapment of incompatible element boundary layers or dissolution/precipitation. The observed wide range of TiO2 contents in the host feldspar, and between bands of melt inclusions within individual crystals rule out modification of TiO contents by diffusion, either pre-eruption or due to re-homogenization. However, we do observe comparatively small ranges for values of K2O and Sr compared to P2O5 and TiO2 in both inclusions and crystals that can be attributed to diffusive processes that occurred prior to eruption.
The U.S. Geological Survey coal quality (COALQUAL) database version 3.0
Palmer, Curtis A.; Oman, Charles L.; Park, Andy J.; Luppens, James A.
2015-12-21
Because of database size limits during the development of COALQUAL Version 1.3, many analyses of individual bench samples were merged into whole coal bed averages. The methodology for making these composite intervals was not consistent. Size limits also restricted the amount of georeferencing information and forced removal of qualifier notations such as "less than detection limit" (<) information, which can cause problems when using the data. A review of the original data sheets revealed that COALQUAL Version 2.0 was missing information that was needed for a complete understanding of a coal section. Another important database issue to resolve was the USGS "remnant moisture" problem. Prior to 1998, tests for remnant moisture (as-determined moisture in the sample at the time of analysis) were not performed on any USGS major, minor, or trace element coal analyses. Without the remnant moisture, it is impossible to convert the analyses to a usable basis (as-received, dry, etc.). Based on remnant moisture analyses of hundreds of samples of different ranks (and known residual moisture) reported after 1998, it was possible to develop a method to provide reasonable estimates of remnant moisture for older data to make it more useful in COALQUAL Version 3.0. In addition, COALQUAL Version 3.0 is improved by (1) adding qualifiers, including statistical programming to deal with the qualifiers; (2) clarifying the sample compositing problems; and (3) adding associated samples. Version 3.0 of COALQUAL also represents the first attempt to incorporate data verification by mathematically crosschecking certain analytical parameters. Finally, a new database system was designed and implemented to replace the outdated DOS program used in earlier versions of the database.
Exchangeable Ions Are Responsible for the In Vitro Antibacterial Properties of Natural Clay Mixtures
Otto, Caitlin C.; Haydel, Shelley E.
2013-01-01
We have identified a natural clay mixture that exhibits in vitro antibacterial activity against a broad spectrum of bacterial pathogens. We collected four samples from the same source and demonstrated through antibacterial susceptibility testing that these clay mixtures have markedly different antibacterial activity against Escherichia coli and methicillin-resistant Staphylococcus aureus (MRSA). Here, we used X-ray diffraction (XRD) and inductively coupled plasma – optical emission spectroscopy (ICP-OES) and – mass spectrometry (ICP-MS) to characterize the mineralogical and chemical features of the four clay mixture samples. XRD analyses of the clay mixtures revealed minor mineralogical differences between the four samples. However, ICP analyses demonstrated that the concentrations of many elements, Fe, Co, Cu, Ni, and Zn, in particular, vary greatly across the four clay mixture leachates. Supplementation of a non-antibacterial leachate containing lower concentrations of Fe, Co, Ni, Cu, and Zn to final ion concentrations and a pH equivalent to that of the antibacterial leachate generated antibacterial activity against E. coli and MRSA, confirming the role of these ions in the antibacterial clay mixture leachates. Speciation modeling revealed increased concentrations of soluble Cu2+ and Fe2+ in the antibacterial leachates, compared to the non-antibacterial leachates, suggesting these ionic species specifically are modulating the antibacterial activity of the leachates. Finally, linear regression analyses comparing the log10 reduction in bacterial viability to the concentration of individual ion species revealed positive correlations with Zn2+ and Cu2+ and antibacterial activity, a negative correlation with Fe3+, and no correlation with pH. Together, these analyses further indicate that the ion concentration of specific species (Fe2+, Cu2+, and Zn2+) are responsible for antibacterial activity and that killing activity is not solely attributed to pH. PMID:23691149
Surgical adverse outcome reporting as part of routine clinical care.
Kievit, J; Krukerink, M; Marang-van de Mheen, P J
2010-12-01
In The Netherlands, health professionals have created a doctor-driven standardised system to report and analyse adverse outcomes (AO). The aim is to improve healthcare by learning from past experiences. The key elements of this system are (1) an unequivocal definition of an adverse outcome, (2) appropriate contextual information and (3) a three-dimensional hierarchical classification system. First, to assess whether routine doctor-driven AO reporting is feasible. Second, to investigate how doctors can learn from AO reporting and analysis to improve the quality of care. Feasibility was assessed by how well doctors reported AO in the surgical department of a Dutch university hospital over a period of 9 years. AO incidence was analysed per patient subgroup and over time, in a time-trend analysis of three equal 3-year periods. AO were analysed case by case and statistically, to learn lessons from past events. In 19,907 surgical admissions, 9189 AOs were reported: one or more AO in 18.2% of admissions. On average, 55 lessons were learnt each year (in 4.3% of AO). More AO were reported in P3 than P1 (OR 1.39 (1.23-1.57)). Although minor AO increased, fatal AO decreased over time (OR 0.59 (0.45-0.77)). Doctor-driven AO reporting is shown to be feasible. Lessons can be learnt from case-by-case analyses of individual AO, as well as by statistical analysis of AO groups and subgroups (illustrated by time-trend analysis), thus contributing to the improvement of the quality of care. Moreover, by standardising AO reporting, data can be compared across departments or hospitals, to generate (confidential) mirror information for professionals cooperating in a peer-review setting.
Surgical adverse outcome reporting as part of routine clinical care
Krukerink, M; Marang-van de Mheen, P J
2010-01-01
Background In The Netherlands, health professionals have created a doctor-driven standardised system to report and analyse adverse outcomes (AO). The aim is to improve healthcare by learning from past experiences. The key elements of this system are (1) an unequivocal definition of an adverse outcome, (2) appropriate contextual information and (3) a three-dimensional hierarchical classification system. Objectives First, to assess whether routine doctor-driven AO reporting is feasible. Second, to investigate how doctors can learn from AO reporting and analysis to improve the quality of care. Methods Feasibility was assessed by how well doctors reported AO in the surgical department of a Dutch university hospital over a period of 9 years. AO incidence was analysed per patient subgroup and over time, in a time-trend analysis of three equal 3-year periods. AO were analysed case by case and statistically, to learn lessons from past events. Results In 19 907 surgical admissions, 9189 AOs were reported: one or more AO in 18.2% of admissions. On average, 55 lessons were learnt each year (in 4.3% of AO). More AO were reported in P3 than P1 (OR 1.39 (1.23–1.57)). Although minor AO increased, fatal AO decreased over time (OR 0.59 (0.45–0.77)). Conclusions Doctor-driven AO reporting is shown to be feasible. Lessons can be learnt from case-by-case analyses of individual AO, as well as by statistical analysis of AO groups and subgroups (illustrated by time-trend analysis), thus contributing to the improvement of the quality of care. Moreover, by standardising AO reporting, data can be compared across departments or hospitals, to generate (confidential) mirror information for professionals cooperating in a peer-review setting. PMID:20430928
Workforce Diversity: Monitoring Employment Trends in Public Organizations.
ERIC Educational Resources Information Center
Guajardo, Salomon A.
1999-01-01
Presents the use of research designs that can be used by human resource specialists to evaluate and monitor work force diversity and minority employment. Compares results of Repeated Measure Analyses of Variance with One Within-subjects Factor design with Repeated Measure Analyses of Variance with One Within-subjects Factor by job category. (JOW)
78 FR 53135 - Agency Information Collection Extension
Federal Register 2010, 2011, 2012, 2013, 2014
2013-08-28
... Synfuel data Minor revisions to instructions and definitions Form EIA-7A: Coal Production and Preparation... Production and Preparation Report;'' EIA-8A ``Coal Stocks Report;'' EIA-20 ``Weekly Coal Monitoring Report... environment. EIA surveys are conducted to collect coal market data. The data elements include production...
Weld microfissuring in Inconel 718 minimized by minor elements
NASA Technical Reports Server (NTRS)
Morrison, T. J.; Shira, C. S.; Weisenberg, L. A.
1968-01-01
Manganese, silicon, and magnesium markedly reduce the tendency of Inconel 718 to weld microfissuring. By combining a manganese, 0.20 percent by content, with silicon, greater than 0.25 percent content, or by adding 20 ppm of magnesium, the weld microfissuring decreased in the standard alloy.
Poon, Matthew; Schutz, Michael
2015-01-01
Acoustic cues such as pitch height and timing are effective at communicating emotion in both music and speech. Numerous experiments altering musical passages have shown that higher and faster melodies generally sound “happier” than lower and slower melodies, findings consistent with corpus analyses of emotional speech. However, equivalent corpus analyses of complex time-varying cues in music are less common, due in part to the challenges of assembling an appropriate corpus. Here, we describe a novel, score-based exploration of the use of pitch height and timing in a set of “balanced” major and minor key compositions. Our analysis included all 24 Preludes and 24 Fugues from Bach’s Well-Tempered Clavier (book 1), as well as all 24 of Chopin’s Preludes for piano. These three sets are balanced with respect to both modality (major/minor) and key chroma (“A,” “B,” “C,” etc.). Consistent with predictions derived from speech, we found major-key (nominally “happy”) pieces to be two semitones higher in pitch height and 29% faster than minor-key (nominally “sad”) pieces. This demonstrates that our balanced corpus of major and minor key pieces uses low-level acoustic cues for emotion in a manner consistent with speech. A series of post hoc analyses illustrate interesting trade-offs, with sets featuring greater emphasis on timing distinctions between modalities exhibiting the least pitch distinction, and vice-versa. We discuss these findings in the broader context of speech-music research, as well as recent scholarship exploring the historical evolution of cue use in Western music. PMID:26578990
Dynamics of vaccination strategies via projected dynamical systems.
Cojocaru, Monica-Gabriela; Bauch, Chris T; Johnston, Matthew D
2007-07-01
Previous game theoretical analyses of vaccinating behaviour have underscored the strategic interaction between individuals attempting to maximise their health states, in situations where an individual's health state depends upon the vaccination decisions of others due to the presence of herd immunity. Here, we extend such analyses by applying the theories of variational inequalities (VI) and projected dynamical systems (PDS) to vaccination games. A PDS provides a dynamics that gives the conditions for existence, uniqueness and stability properties of Nash equilibria. In this paper, it is used to analyse the dynamics of vaccinating behaviour in a population consisting of distinct social groups, where each group has different perceptions of vaccine and disease risks. In particular, we study populations with two groups, where the size of one group is strictly larger than the size of the other group (a majority/minority population). We find that a population with a vaccine-inclined majority group and a vaccine-averse minority group exhibits higher average vaccine coverage than the corresponding homogeneous population, when the vaccine is perceived as being risky relative to the disease. Our model also reproduces a feature of real populations: In certain parameter regimes, it is possible to have a majority group adopting high vaccination rates and simultaneously a vaccine-averse minority group adopting low vaccination rates. Moreover, we find that minority groups will tend to exhibit more extreme changes in vaccinating behaviour for a given change in risk perception, in comparison to majority groups. These results emphasise the important role played by social heterogeneity in vaccination behaviour, while also highlighting the valuable role that can be played by PDS and VI in mathematical epidemiology.
Mereish, Ethan H.; Bradford, Judith B.
2014-01-01
Objective: Research has documented that sexual minorities are at greater risk for substance use than heterosexuals. However, there are limited studies and mixed findings when investigating these health disparities among racial and ethnic minority samples. We used an intersectionality framework to examine disparities in lifetime substance use problems between heterosexual and sexual minority men and women and within sexual minority groups among a racially diverse sample. Method: A nonprobability sample of heterosexual (n = 1,091) and sexual minority (n = 1,465) patients from an urban community health center ranged in age from 18 to 72 years. Participants completed a brief patient survey and reported demographic information and history of lifetime substance use problems. Logistic regressions analyses were used to examine interactions between and among sexual orientation, gender, and race. Results: We found a significant three-way interaction among sexual orientation, gender, and race. Sexual minorities had a greater risk of self-reported lifetime substance use problems than heterosexuals, with nuanced gender and racial differences. Of greatest note, sexual minority women of color had greater risks than heterosexual women of color and than White sexual minority women. Sexual minority men of color did not differ in their risk when compared with heterosexual men of color, and they had lower risk than White sexual minority men. Conclusions: The results of this study demonstrate that an intersectionality framework is crucial to clearly identify lifetime substance use disparities between racially diverse sexual minority and heterosexual men and women. Future research, treatment, and policy should use intersectionality approaches when addressing substance use disparities. PMID:24411810
Evidence for montmorillonite or its compositional equivalent in Columbia Hills, Mars
Clark, B. C.; Arvidson, R. E.; Gellert, Ralf; Morris, R.V.; Ming, D. W.; Richter, L.; Ruff, S.W.; Michalski, J.R.; Farrand, W. H.; Yen, A. S.; Herkenhoff, K. E.; Li, R.; Squyres, S. W.; Schroder, C.; Klingelhofer, G.; Bell, J.F.
2007-01-01
During its exploration of the Columbia Hills, the Mars Exploration Rover "Spirit" encountered several similar samples that are distinctly different from Martian meteorites and known Gusev crater soils, rocks, and sediments. Occurring in a variety of contexts and locations, these "Independence class" samples are rough-textured, iron-poor (equivalent FeO ??? 4 wt%), have high Al/Si ratios, and often contain unexpectedly high concentrations of one or more minor or trace elements (including Cr, Ni, Cu, Sr, and Y). Apart from accessory minerals, the major component common to these samples has a compositional profile of major and minor elements which is similar to the smectite montmorillonite, implicating this mineral, or its compositional equivalent. Infrared thermal emission spectra do not indicate the presence of crystalline smectite. One of these samples was found spatially associated with a ferric sulfate-enriched soil horizon, possibly indicating a genetic relationship between these disparate types of materials. Compared to the nearby Wishstone and Watchtower class rocks, major aqueous alteration involving mineral dissolution and mobilization with consequent depletions of certain elements is implied for this setting and may be undetectable by remote sensing from orbit because of the small scale of the occurrences and obscuration by mantling with soil and dust. Copyright 2007 by the American Geophysical Union.
Sexual minority status, peer harassment, and adolescent depression.
Martin-Storey, Alexa; Crosnoe, Robert
2012-08-01
The well-documented higher rates of depression among sexual minority youth are increasingly viewed by developmentalists as a byproduct of the stigmatization of sexual minority status in American society and of the negative impact this stigma has on the processes associated with depression. This study attempted to spur future research by testing Hatzenbuehler's (2009) psychological mediation framework to investigate the ways in which peer harassment related to sexuality puts young people at risk by influencing the cognitive, social, and regulatory factors associated with depression. Analyses of 15 year olds in the NICHD Study of Early Child Care and Youth Development revealed that sexual minority status was largely associated with depressive outcomes via harassment, which was subsequently associated with depression via cognitive and social factors. Results point to various avenues for exploring the importance of the social world and self-concept for the outcomes of sexual minority adolescents in the future. Copyright © 2012 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.
Buttram, Mance E.; Surratt, Hilary L.; Kurtz, Steven P.
2014-01-01
Research among sexual minorities has traditionally examined problems such as substance use, HIV risk, mental health problems, and victimization. Among sexual minority street-based female sex workers, these vulnerabilities can be magnified. Grounded in theories of resilience, this study examines risk and protective factors associated with a high level of personal mastery among a vulnerable population of women. Data are drawn from baseline interviews from street-based African American female sex workers enrolled in a randomized intervention trial in Miami, Florida. We compare sexual minority (N=197) and heterosexual (N=365) women on measures of risk and protective factors; among sexual minority women we present logistic regression analyses which reveal that severe mental distress and HIV transmission risk are associated with low levels of personal mastery, while protective factors of transportation access and social support are associated with high levels of personal mastery. These findings suggest that these protective factors may potentially facilitate the development of personal mastery and represent beneficial avenues for intervention efforts. PMID:25530691
Vilchinsky, Noa; Reges, Orna; Leibowitz, Morton; Khaskia, Abdulrahim; Mosseri, Morris; Kark, Jeremy D
2018-05-01
Despite its proven efficacy, low participation rates in cardiac prevention and rehabilitation programs (CPRPs) prevail worldwide, especially among ethnic minorities. This is strongly evident in Israel's Arab minority. Since psychological distress has been found to be associated with CPRP participation and minorities are subjected to higher levels of distress, it is plausible that distress may be an important barrier for CPRP participation among minority patients. The current prospective study assessed the contribution of depression and anxiety symptoms to participation in a CPRP after acute coronary syndrome, both in the enrollment phase and when considering adherence over time, among Jewish (majority) and Arab (minority) patients in Israel. Patients were interviewed during hospitalization about their emotional status and at a 6-mo follow-up concerning participation in a CPRP. Analyses were performed on 397 patients. The Brief Symptom Inventory was used. Logistic regression modeling was applied. Symptoms of depression, but not anxiety, were frequently observed among Arab patients compared with their Jewish counterparts. In analyses adjusted for age, sex, ethnicity, and sociodemographic and clinical characteristics, having symptoms of anxiety was associated with less participation in a CPRP, evident for both Jews and Arabs; this association was less evident for symptoms of depression. Multivariable adjusted models did not show a significant association of symptoms of anxiety or depression with adherence in a CPRP. Accounting for psychological distress did not reduce the sharp difference between Jews and Arabs in CPRP participation. Symptoms of distress may serve as barriers to CPRP participation, regardless of ethnic origin.
NASA Astrophysics Data System (ADS)
Aiuppa, Alessandro; Allard, Patrick; D'Alessandro, Walter; Michel, Agnes; Parello, Francesco; Treuil, Michel; Valenza, Mariano
2000-06-01
The concentrations and fluxes of major, minor and trace metals were determined in 53 samples of groundwaters from around Mt Etna, in order to evaluate the conditions and extent of alkali basalt weathering by waters enriched in magma-derived CO 2 and the contribution of aqueous transport to the overall metal discharge of the volcano. We show that gaseous input of magmatic volatile metals into the Etnean aquifer is small or negligible, being limited by cooling of the rising fluids. Basalt leaching by weakly acidic, CO 2-charged water is the overwhelming source of metals and appears to be more extensive in two sectors of the S-SW (Paternò) and E (Zafferana) volcano flanks, where out flowing groundwaters are the richest in metals and bicarbonate of magmatic origin. Thermodynamic modeling of the results allows to evaluate the relative mobility and chemical speciation of various elements during their partitioning between solid and liquid phases through the weathering process. The facts that rock-forming minerals and groundmass dissolve at different rates and secondary minerals are formed are taken into account. At Mt. Etna, poorly mobile elements (Al, Th, Fe) are preferentially retained in the solid residue of weathering, while alkalis, alkaline earth and oxo-anion-forming elements (As, Se, Sb, Mo) are more mobile and released to the aqueous system. Transition metals display an intermediate behavior and are strongly dependent on either the redox conditions (Mn, Cr, V) or solid surface-related processes (V, Zn, Cu). The fluxes of metals discharged by the volcanic aquifer of Etna range from 7.0 × 10 -3 t/a (Th) to 7.3 × 10 4 t/a (Na). They are comparable in magnitude to the summit crater plume emissions for a series of elements (Na, K, Ca, Mg, U, V, Li) with lithophile affinity, but are minor for volatile elements. Basalt weathering at Mt Etna also consumes about 2.1 × 10 5 t/a of magma-derived carbon dioxide, equivalent to ca. 7% of contemporaneous crater plume emissions. The considerable transport of some metals in Etna's aquifer reflects a particularly high chemical erosion rate, evaluated at 2.3∗10 5 t/a, enhanced by the initial acidity of magmatic CO 2-rich groundwater.
Self-care and depression in patients with chronic heart failure.
Holzapfel, Nicole; Löwe, Bernd; Wild, Beate; Schellberg, Dieter; Zugck, Christian; Remppis, Andrew; Katus, Hugo A; Haass, Markus; Rauch, Bernhard; Jünger, Jana; Herzog, Wolfgang; Müller-Tasch, Thomas
2009-01-01
Although chronic heart failure (CHF) is often complicated by comorbid depression and poor self-care, little is known about their specific association in patients with CHF. To investigate self-care behavior among patients with CHF with different degrees of depression severity. A total of 287 patients with documented CHF, New York Heart Association functional class II to IV, completed the European Heart Failure Self-Care Behavior Scale. The Structured Clinical Interview for DSM (SCID) IV served as the criterion standard for the presence of a depressive disorder. Analyses of covariance and linear regression analyses revealed that patients with CHF with minor depression reported significantly lower levels of self-care than patients with major depression (P = .003) and nondepressed patients (P = .014). In addition to minor depression, age (P < or = .001), multimorbidity (P = .01), left ventricular ejection fraction (P = .001), and family status (P = .01) were determinants of self-care. Our results demonstrate that patients with CHF with minor depression and not major depression are at higher risk for poor self-care and its resulting consequences, such as symptom deterioration and frequent hospitalization.
Health Indicators for Older Sexual Minorities: National Health Interview Survey, 2013–2014
Laffan, Alison M.; Erdem, Erkan; Cahill, Sean R.; Kenefick, Daniel; Ye, Jiahui; Haffer, Samuel C.
2017-01-01
Abstract Purpose: Advances in lesbian, gay, and bisexual (sexual minority [SM]) acceptance and equality have been made in the past decade. However, certain SM subgroups continue to be disadvantaged due to lack of data and, thus, lack of knowledge about these populations. Data for older sexual minorities are especially lacking and will be increasingly important as more sexual minorities enter older age. This research explores results from a nationally representative health survey to elucidate some health indicators for older sexual minorities. Methods: Data from the 2013 and 2014 National Health Interview Surveys (NHIS) were pooled for increased sample size, and established research methods were followed as recommended by prior NHIS sexual orientation studies. We conducted descriptive analyses on the differences between SM and heterosexual groups, aged 65 years and older, for 12 health indicators. Results: Four out of the 12 health indicators were significantly different for sexual minorities, and three out of those four indicated positive health outcomes or behaviors when compared with heterosexuals. Sexual minorities were more than three times as likely to receive HIV testing as heterosexual peers. Sexual minorities were more likely to receive an influenza vaccination, and much more likely to report excellent or very good health, than their heterosexual peers. Sexual minorities were more than twice as likely to report binge drinking, which is consistent with prior research for adult sexual minorities. Conclusion: This analysis is the first to examine national data on health indicators for sexual minorities, aged 65 years and older, using NHIS data. As more surveys begin to collect SMdata and more years of data are collected by NHIS, a clearer picture of the health of older adult sexual minorities should emerge. PMID:29028455
Health Indicators for Older Sexual Minorities: National Health Interview Survey, 2013-2014.
Dragon, Christina N; Laffan, Alison M; Erdem, Erkan; Cahill, Sean R; Kenefick, Daniel; Ye, Jiahui; Haffer, Samuel C
2017-12-01
Advances in lesbian, gay, and bisexual (sexual minority [SM]) acceptance and equality have been made in the past decade. However, certain SM subgroups continue to be disadvantaged due to lack of data and, thus, lack of knowledge about these populations. Data for older sexual minorities are especially lacking and will be increasingly important as more sexual minorities enter older age. This research explores results from a nationally representative health survey to elucidate some health indicators for older sexual minorities. Data from the 2013 and 2014 National Health Interview Surveys (NHIS) were pooled for increased sample size, and established research methods were followed as recommended by prior NHIS sexual orientation studies. We conducted descriptive analyses on the differences between SM and heterosexual groups, aged 65 years and older, for 12 health indicators. Four out of the 12 health indicators were significantly different for sexual minorities, and three out of those four indicated positive health outcomes or behaviors when compared with heterosexuals. Sexual minorities were more than three times as likely to receive HIV testing as heterosexual peers. Sexual minorities were more likely to receive an influenza vaccination, and much more likely to report excellent or very good health, than their heterosexual peers. Sexual minorities were more than twice as likely to report binge drinking, which is consistent with prior research for adult sexual minorities. This analysis is the first to examine national data on health indicators for sexual minorities, aged 65 years and older, using NHIS data. As more surveys begin to collect SMdata and more years of data are collected by NHIS, a clearer picture of the health of older adult sexual minorities should emerge.
Electrically conductive resinous bond and method of manufacture
Snowden, T.M. Jr.; Wells, B.J.
1985-01-01
A method of bonding elements together with a bond of high strength and good electrical conductivity which comprises: applying an unfilled polyimide resin between surfaces of the elements to be bonded, heat treating said unfilled polyimide resin in stages between a temperature range of about 40 to 365/sup 0/C to form a strong adhesive bond between said elements, applying a metal-filled polyimide resin overcoat between said elements so as to provide electrical connection therebetween, and heat treating said metal-filled polyimide resin with substantially the same temperature profile as the unfilled polyimide resin. The present invention is also concerned with an adhesive, resilient, substantially void free bonding combination for providing a high strength, electrically conductive adhesive attachment between electrically conductive elements which comprises a major amount of an unfilled polyimide resin and a minor amount of a metal-filled polyimide resin.
Electrically conductive resinous bond and method of manufacture
Snowden, Jr., Thomas M.; Wells, Barbara J.
1987-01-01
A method of bonding elements together with a bond of high strength and good electrical conductivity which comprises: applying an unfilled polyimide resin between surfaces of the elements to be bonded, heat treating said unfilled polyimide resin in stages between a temperature range of about 40.degree. to 365.degree. C. to form a strong adhesive bond between said elements, applying a metal-filled polyimide resin overcoat between said elements so as to provide electrical connection therebetween, and heat treating said metal-filled polyimide resin with substantially the same temperature profile as the unfilled polyimide resin. The present invention is also concerned with an adhesive, resilient, substantially void free bonding combination for providing a high strength, electrically conductive adhesive attachment between electrically conductive elements which comprises a major amount of an unfilled polyimide resin and a minor amount of a metal-filled polyimide resin.
Demandite, lunar materials and space industrialization
NASA Technical Reports Server (NTRS)
Criswell, D. R.
1977-01-01
Terrestrial industry consumes a wide range of elements in producing the outputs which support and make industrial societies possible. 'Demandite' is a conceptual or synthetic molecule which is composed of the weight fractions of the major elements consumed by industry. Demandite needed for mature industrial activities in space will differ from the terrestrial composition because solar energy must replace hydrocarbon-energy, lunar and asteroidal bulk compositions are different from mineral deposits on the earth, and the major bulk processing in space will be the creation of radiation shielding for human habitats to provide real estate in space complete with water, atmosphere and life-stock elements. Demandite cost may be dominated by earth to deep space transport cost of minor elemental constituents depleted in the lunar soils unless careful attention is given to substitution of materials, searches of the moon (polar regions) and asteroids for the depleted elements, and continuing lowering of earth to deep space transport costs.
NASA Astrophysics Data System (ADS)
Kurat, G.; Palme, H.; Spettel, B.; Baddenhausen, Hildegard; Hofmeister, H.; Palme, Christl; Wänke, H.
1980-01-01
Major, minor, and trace element contents have been determined in seven ultramafic xenoliths, the host basanite, and some mineral separates from xenoliths from Kapfenstein, Austria. Most of the xenoliths represent residues after extraction of different amounts of basaltic liquid. Within the sequence Iherzolite to harzburgite contents of Al, Ca, Ti, Na, Sc, V, Cr and the HREE decrease systematically with increasing Mg/Fe and decreasing Yb/Sc. Although all samples are depleted in highly incompatible elements, the less depleted end of our suite very closely approaches the chondritic Yb/Sc ratio and consequently the primitive upper mantle composition. Chromium behaved as a non-refractory element. Consequently it should have higher abundances in basalts than observed, suggesting that most basalts experienced Cr fractionation by chromite separation during ascent. Several processes have been active in addition to partial melting within the upper mantle beneath Kapfenstein: (1) a hornblendite has been identified as wet alkali-basaltic mobilisate; (2) an amphibole Iherzolite is the product of alkali-basalt metasomatism of a common depleted Iherzolite; (3) two amphibole Iherzolites contain evidence for rather pure water metasomatism of normal depleted Iherzolites; (4) a garnet-spinel websterite was a tholeiitic liquid trapped within the upper mantle and which suffered a subsequent partial melting event (partial remobilization of a mobilisate). (5) Abundances of highly incompatible elements are generally very irregular, indicating contamination of upper mantle rocks by percolating liquids (in the mantle). Weathering is an important source of contamination: e.g. U mobilization by percolating groundwater. Contamination of the xenoliths by the host basanite liquid can only amount to approximately 5.5 × 10 -4 parts. Distributions of minor and trace elements between different minerals apparently reflect equilibrium and vary with equilibration temperature.
Superelement Analysis of Tile-Reinforced Composite Armor
NASA Technical Reports Server (NTRS)
Davila, Carlos G.
1998-01-01
Super-elements can greatly improve the computational efficiency of analyses of tile-reinforced structures such as the hull of the Composite Armored Vehicle. By taking advantage of the periodicity in this type of construction, super-elements can be used to simplify the task of modeling, to virtually eliminate the time required to assemble the stiffness matrices, and to reduce significantly the analysis solution time. Furthermore, super-elements are fully transferable between analyses and analysts, so that they provide a consistent method to share information and reduce duplication. This paper describes a methodology that was developed to model and analyze large upper hull components of the Composite Armored Vehicle. The analyses are based on two types of superelement models. The first type is based on element-layering, which consists of modeling a laminate by using several layers of shell elements constrained together with compatibility equations. Element layering is used to ensure the proper transverse shear deformation in the laminate rubber layer. The second type of model uses three-dimensional elements. Since no graphical pre-processor currently supports super-elements, a special technique based on master-elements was developed. Master-elements are representations of super-elements that are used in conjunction with a custom translator to write the superelement connectivities as input decks for ABAQUS.
Chemical composition of rocks and soils at Taurus-Littrow
NASA Technical Reports Server (NTRS)
Rose, H. J., Jr.; Cuttitta, F.; Berman, S.; Brown, F. W.; Carron, M. K.; Christian, R. P.; Dwornik, E. J.; Greenland, L. P.
1974-01-01
Seventeen soils and seven rock samples were analyzed for major elements, minor elements, and trace elements. Unlike the soils at previous Apollo sites, which showed little difference in composition at each collection area, the soils at Taurus-Littrow vary widely. Three soil types are evident, representative of (1) the light mantle at the South Massif, (2) the dark mantle in the valley, and (3) the surface material at the North Massif. The dark-mantle soils are chemically similar to those at Tranquillitatis. Basalt samples from the dark mantle are chemically similar although they range from fine to coarse grained. It is suggested that they originated from the same source but crystallized at varying depths from the surface.
41 CFR 60-2.17 - Additional required elements of affirmative action programs.
Code of Federal Regulations, 2011 CFR
2011-07-01
... selection disparities; (3) Compensation system(s) to determine whether there are gender-, race-, or... determine whether they result in disparities in the employment or advancement of minorities or women; and (5... Other Provisions Relating to Public Contracts OFFICE OF FEDERAL CONTRACT COMPLIANCE PROGRAMS, EQUAL...
Wildland fire emits a substantial quantity of aerosol to the atmosphere. These aerosols typically comprise a complex mixture of organic matter and refractory elemental or black carbon with a relatively minor contribution of inorganic matter from soils and plant micronutrients. Id...
Understanding and Enhancing Multicultural Teaching in Preschool
ERIC Educational Resources Information Center
Leung, Chi-Hung; Hue, Ming-Tak
2017-01-01
Preschool teachers are an important element of high-quality, developmentally and multiculturally appropriate early childhood programmes. 7.5% of the total 160,000 children enrolled in Hong Kong kindergartens are ethnic-minority students and they are neglected in the Hong Kong education system until 2008. This study investigated the perceptions of…
12 CFR 567.5 - Components of capital.
Code of Federal Regulations, 2011 CFR
2011-01-01
... Requirements § 567.5 Components of capital. (a) Core Capital. (1) The following elements, 3 less the amount of any deductions pursuant to paragraph (a)(2) of this section, comprise a savings association' s core... includable in core capital. (iii) Minority interests in the equity accounts of the subsidiaries that are...
Recruitment of Hispanic and Black Students.
ERIC Educational Resources Information Center
Rivera, Manuel G.
The issue of recruitment of community college minority students who are underrepresented in higher education (Hispanics and Blacks) is complex and needs various programs which are unique and fit within the framework of the institution. Historical elements in Texas make it difficult to implement recruitment efforts. Recent statistics illustrate the…
40 CFR 98.144 - Monitoring and QA/QC requirements.
Code of Federal Regulations, 2012 CFR
2012-07-01
... calibrated scales or weigh hoppers. Total annual mass charged to glass melting furnaces at the facility shall... mineral mass fractions at least annually to verify the mass fraction data provided by the supplier of the... (Reapproved 2006) Standard Test Method for Major and Minor Elements in Combustion Residues from Coal...
NASA Astrophysics Data System (ADS)
Veevers, J. J.; Saeed, A.
2007-12-01
In conjugate SE Africa and Antarctica, Early Permian sandstones of the Swartrant Formation of the Ellisras Basin, Vryheid Formation of the Karoo Basin, and Amelang Plateau Formation of Dronning Maud Land (DML) were deposited after Gondwanan glaciation on a westward paleoslope. We analysed detrital zircons for U-Pb ages by a laser ablation microprobe-inductively coupled plasma mass spectrometer (LAM-ICPMS) and attached age significance only to clusters of three or more overlapping analyses. We analysed Hf-isotope compositions by a multi-collector spectrometer (LAM-MC-ICPMS) and trace elements by electron microprobe (EMP) and ICPMS. These analyses indicate the rock type and source (whether crustal or juvenile mantle) of the host magma, and a "crustal" model age ( TDMC). The integrated analysis gives a more distinctive, and more easily interpreted, picture of crustal evolution in the provenance area than age data alone. Zircons from the Ellisras Basin are aged 2700-2540 Ma with minor populations about 2815 Ma and 2040 Ma, which correspond with the ages of the upslope parts of the proximal Kaapvaal Craton and Limpopo Belt. Mafic rock is the dominant host rock, and it reflects the Archean granite-greenstone terrane of the Kaapvaal Craton. The three Karoo Basin samples and the two DML samples have zircons with these common properties: (1) 1160-880 Ma, host magma mafic granitoid (< 65% SiO 2) derived from juvenile depleted mantle sources ( ɛHf positive) at 1.65 Ga and 1.35 Ga, with TDMC of 2.0-0.9 Ga; (2) 760 to 480 Ma, host magma granitoid and low-heavy rare earth element rock (?alkaline rock-carbonatite), derived from mixed crustal and juvenile depleted mantle sources ( ɛHf positive and negative) at 1.50 Ga and 1.35 Ga, with TDMC of 2.0-0.9 Ga. Together with similar detrital zircons in Triassic sandstone of SE Australia, these properties reflect those in upslope central Antarctica, indicating a provenance of ˜ 1000 Ma (Grenville) cratons embedded in 700-500 Ma (Pan-Gondwanaland) fold belts. Detrital zircons in Cambrian sediments of the Ellsworth-Whitmore Mountains block and Cambrian metasediments of the Welch Mountains with comparable properties suggest that the central Antarctic provenance operated also in the ˜ 500 Ma Cambrian.
The expression of APRIL in Sjögren’s syndrome: aberrant expression of APRIL in the salivary gland
Roescher, Nienke; Polling, Eline J.; Illei, Gabor G.; Tak, Paul P.
2012-01-01
Objective. A proliferation-inducing ligand (APRIL) and B-cell activating factor (BAFF) are B-cell-related mediators and may play a role in the pathogenesis in SS. In this descriptive study we assessed the expression of APRIL and BAFF in the minor salivary gland and serum from SS patients. Methods. Paraffin-embedded minor salivary gland sections from SS patients, non-SS controls and healthy volunteers were analysed by immunohistochemistry. Digital image quantification was performed to evaluate the expression of BAFF, APRIL and transmembrane activator and CAML interactor. Furthermore, serum was analysed for soluble BAFF and APRIL levels by ELISA. All the data were also analysed for subjects with decreased and normal stimulated salivary flow independent of the classification. Results. APRIL expression was lower in minor salivary gland biopsies from SS patients compared with healthy volunteers and to a lesser extent non-SS controls, whereas BAFF expression was similar in all groups. Soluble APRIL levels in serum were increased in SS patients and in subjects with decreased salivary flow independent of the classification. Conclusion. APRIL salivary gland tissue levels are decreased, suggesting that targeting this cytokine locally in the salivary glands would not benefit SS patients. Moreover, the discrepancy between local and systemic levels is striking and future research should assess this in more detail. PMID:22562936
Bottom sediments and pore waters near a hydrothermal vent in Lake Baikal (Frolikha Bay)
Granina, L.Z.; Klerkx, J.; Callender, E.; Leermakers, M.; Golobokova, L.P.
2007-01-01
We discuss the redox environments and the compositions of bottom sediments and sedimentary pore waters in the region of a hydrothermal vent in Frolikha Bay, Lake Baikal. According to our results, the submarine vent and its companion nearby spring on land originate from a common source. The most convincing evidence for their relation comes from the proximity of stable oxygen and hydrogen isotope compositions in pore waters and in the spring water. The isotope composition indicates a meteoric origin of pore waters, but their major- and minor-element chemistry bears imprint of deep water which may seep through permeable faulted crust. Although pore waters near the submarine vent have a specific enrichment in major and minor constituents, hydrothermal discharge at the Baikal bottom causes a minor impact on the lake water chemistry, unlike the case of freshwater geothermal lakes in the East-African Rift and North America. ?? 2007.
Coming Out Experiences of Hispanic Sexual Minority Young Adults in South Florida.
Gattamorta, Karina; Quidley-Rodriguez, Narciso
2017-08-03
Sexual minority youth and young adults (SMYYA) have higher prevalence of mental and behavioral health problems potentially linked to experiences of discrimination, stigma, and rejection. Among Hispanics, the intersection of stressors related to being an ethnic and sexual minority may result in compounding adverse outcomes. Coming out may play an important role in experiencing discrimination, stigma, and rejection. However, limited research examines coming out among Hispanic SMYYA (HSMYYA). This qualitative study seeks to understand the coming-out experiences of HSMYYA living in South Florida. Twenty participants between 18 and 28 years old were interviewed. Qualitative content analysis generated codes, which were grouped into categories to generate themes. This study presents data highlighting reasons for disclosing and not disclosing sexual orientation and the perceived consequences of those decisions. Additionally, we discuss unique cultural elements that impact HSMYYA's decisions to reveal sexual orientation.
The Impact of Education on Inter-Group Attitudes: A Multiracial Analysis
Wodtke, Geoffrey T.
2013-01-01
How does education affect racial attitudes? Past studies focus almost exclusively on Whites’ attitudes toward Blacks, neglecting important minority populations. This study extends previous research by analyzing the effects of education on beliefs about racial stereotypes, discrimination, and affirmative action policies among Whites, Asians, Hispanics, and Blacks. Results indicate that Whites, Hispanics, and Blacks with higher levels of education are more likely to reject negative stereotypes, but these effects are less consistent among Asians. And, although education has consistent positive effects on awareness of discrimination against minorities, a more advanced education is not associated with greater support for racial preferences among any respondent group. Education is, however, related to more favorable attitudes toward race-targeted job training. These results are partly consistent with a revised group conflict perspective positing that education unevenly promotes different elements of the dominant racial ideology among nonwhite minorities, depending on their position in the racial hierarchy. PMID:24409004
Kritek, Phyllis Beck; Hargraves, Martha; Cuellar, Ernestine H.; Dallo, Florence; Gauthier, Donna M.; Holland, Christi A.; Ilkiw, Connie; Swanson, Jane W.; Swanson, Reid
2002-01-01
A national conference convened in May 2001 explored health disparities among minority women. It included 5 one-hour workshops that randomly assigned each participant to 1 of 4 groups. Groups generated recommendations on conference topics and from these identified priority recommendations. Trained facilitators guided groups through brainstorming and weighted voting processes; individual recommendations were submitted in writing. Participants generated 598 recommendations, 71 of them voted as priorities; these were analyzed to capture participants' “messages.” Central themes focused on access issues and cultural incompetence as deterrents to the elimination of health disparities and on education, funding, and community-based, community-driven research as mechanisms for change. Strategies for change included reinventing or expanding the role of minority communities and changing health care itself and “how” it does its work. The essential element in all recommendations was community leadership and control. PMID:11919057
The Impact of Education on Inter-Group Attitudes: A Multiracial Analysis.
Wodtke, Geoffrey T
2012-03-01
How does education affect racial attitudes? Past studies focus almost exclusively on Whites' attitudes toward Blacks, neglecting important minority populations. This study extends previous research by analyzing the effects of education on beliefs about racial stereotypes, discrimination, and affirmative action policies among Whites, Asians, Hispanics, and Blacks. Results indicate that Whites, Hispanics, and Blacks with higher levels of education are more likely to reject negative stereotypes, but these effects are less consistent among Asians. And, although education has consistent positive effects on awareness of discrimination against minorities, a more advanced education is not associated with greater support for racial preferences among any respondent group. Education is, however, related to more favorable attitudes toward race-targeted job training. These results are partly consistent with a revised group conflict perspective positing that education unevenly promotes different elements of the dominant racial ideology among nonwhite minorities, depending on their position in the racial hierarchy.
Extraction of information from major element chemical analyses of lunar basalts
NASA Technical Reports Server (NTRS)
Butler, J. C.
1985-01-01
Major element chemical analyses often form the framework within which similarities and differences of analyzed specimens are noted and used to propose or devise models. When percentages are formed the ratios of pairs of components are preserved whereas many familiar statistical and geometrical descriptors are likely to exhibit major changes. This ratio preserving aspect forms the basis for a proposed framework. An analysis of compositional variability within the data set of 42 major element analyses of lunar reference samples was selected to investigate this proposal.
Katz-Wise, Sabra L.; Rosario, Margaret; Calzo, Jerel P.; Scherer, Emily A.; Sarda, Vishnudas; Austin, S. Bryn
2017-01-01
This research examined endorsement and timing of sexual orientation developmental milestones. Participants were 1235 females and 398 males from the Growing Up Today Study, ages 22 to 29 years, who endorsed a sexual minority orientation (lesbian/gay, bisexual, mostly heterosexual) or reported same-gender sexual behavior (heterosexual with same-gender sexual experience). An online survey measured current sexual orientation and endorsement and timing (age first experienced) of five sexual orientation developmental milestones: same-gender attractions, other-gender attractions, same-gender sexual experience, other-gender sexual experience, and sexual minority identification. Descriptive analyses and analyses to test for gender and sexual orientation group differences were conducted. Results indicated that females were more likely than males to endorse same-gender attraction, other-gender attraction, and other-gender sexual experience, with the most gender differences in endorsement among mostly heterosexuals and heterosexuals with same-gender sexual experience. In general, males reached milestones earlier than females, with the most gender differences in timing among lesbian and gay individuals and heterosexuals with same-gender sexual experience. Results suggest that the three sexual minority developmental milestones may best characterize the experiences of lesbians, gay males, and female and male bisexuals. More research is needed to understand sexual orientation development among mostly heterosexuals and heterosexuals with same-gender sexual experience. PMID:27148762
Katz-Wise, Sabra L; Rosario, Margaret; Calzo, Jerel P; Scherer, Emily A; Sarda, Vishnudas; Austin, S Bryn
2017-02-01
This research examined endorsement and timing of sexual orientation developmental milestones. Participants were 1,235 females and 398 males from the Growing Up Today Study, ages 22 to 29 years, who endorsed a sexual minority orientation (lesbian/gay, bisexual, mostly heterosexual) or reported same-gender sexual behavior (heterosexual with same-gender sexual experience). An online survey measured current sexual orientation and endorsement and timing (age first experienced) of five sexual orientation developmental milestones: same-gender attractions, other-gender attractions, same-gender sexual experience, other-gender sexual experience, and sexual minority identification. Descriptive analyses and analyses to test for gender and sexual orientation group differences were conducted. Results indicated that women were more likely than men to endorse same-gender attraction, other-gender attraction, and other-gender sexual experience, with the most gender differences in endorsement among mostly heterosexuals and heterosexuals with same-gender sexual experience. In general, men reached milestones earlier than women, with the most gender differences in timing among lesbian and gay individuals and heterosexuals with same-gender sexual experience. Results suggest that the three sexual minority developmental milestones may best characterize the experiences of lesbians, gay males, and female and male bisexuals. More research is needed to understand sexual orientation development among mostly heterosexuals and heterosexuals with same-gender sexual experience.
Derkenne, Clément; Lamblin, Antoine; Demaison, Xavier; Darléguy, Adrien
2015-12-01
The wearing of individual protective elements has revolutionized the typology of war wounds. The benefit/risk ratio is particularly satisfying, but several side effects with minor consequences are described, calling for further ergonomic development from manufacturers of these protective elements. This case report describes a meralgia paresthetica by compression of the lateral cutaneous thigh nerve because of the wearing of bulletproof vest. A symptomatic treatment was introduced, and 2 months after the apparition of the symptoms, the patient's condition has improved, with only a slight hypoesthesia remaining. Reprint & Copyright © 2015 Association of Military Surgeons of the U.S.
Synthesis and characterization of surrogate nuclear explosion debris: urban glass matrix
Campbell, Keri; Judge, Elizabeth J.; Dirmyer, Matthew R.; ...
2017-07-26
Surrogate nuclear explosive debris was synthesized and characterized for major, minor, and trace elemental composition as well as uranium isotopics. The samples consisted of an urban glass matrix, equal masses soda lime and cement, doped with 500 ppm uranium with varying enrichments. The surface and cross section morphology were measured with SEM, and the major elemental composition was determined by XPS. LA-ICP-MS was used to measure the uranium isotopic abundance comparing different sampling techniques. Furthermore, the results provide an example of the utility of LA-ICP-MS for forensics applications.
NASA Astrophysics Data System (ADS)
Milidragovic, D.; Zagorevski, A.; Weis, D.; Joyce, N.; Chapman, J. B.
2018-05-01
Primitive, near-primary arc magmas occur as a volumetrically minor ≤100 m thick unit in the Canadian Cordillera of northwestern British Columbia, Canada. These primitive magmas formed an olivine-phyric, picritic tuff near the base of the Middle-Late Triassic Stuhini Group of the Stikine Terrane (Stikinia). A new 40Ar/39Ar age on hornblende from a cross-cutting basaltic dyke constrains the tuff to be older than 221 ± 2 Ma. An 87Sr/86Sr isochron of texturally-unmodified tuff samples yields 212 ± 25 Ma age, which is interpreted to represent syn-depositional equilibration with sea-water. Parental trace element magma composition of the picritic tuff is strongly depleted in most incompatible trace elements relative to MORB and implies a highly depleted ambient arc mantle. High-precision trace element and Hf-Nd-Pb isotopic analyses indicate an origin by mixing of a melt of depleted ambient asthenosphere with ≤2% of subducted sediment melt. Metasomatic addition of non-conservative incompatible elements through melting of subducted Panthalassa Ocean floor sediments accounts for the arc signature of the Stuhini Group picritic tuff, enrichment of light rare earth elements (LREE) relative to heavy rare earth elements (HREE) and high field strength elements (HFSE), and anomalous enrichment in Pb. The inferred Panthalassan sediments are similar in composition to the Neogene-Quaternary sediments of the modern northern Cascadia Basin. The initial Hf isotopic composition of the picritic tuff closely approximates that of the ambient Middle-Late Triassic asthenosphere beneath Stikinia and is notably less radiogenic than the age-corrected Hf isotopic composition of the Depleted (MORB) Mantle reservoir (DM or DMM). This suggests that the ambient asthenospheric mantle end-member experienced melt depletion (F ≤ 0.05) a short time before picrite petrogenesis. The mantle end-member in the source of the Stuhini Group picritic tuff is isotopically similar to the mantle source of enriched mid-ocean ridge basalts (E-MORB) erupted today at the southern end of the Explorer Ridge in northeastern Pacific Ocean. The isotopic similarity between the Middle-Late Triassic ambient mantle under Stikinia, and mantle presently tapped at the southern Explorer Ridge suggests that enriched domains in the northeastern Pacific mantle are long-lived (≥222 million years).
What Should the FeO Content of a Terrestrial Planet Be?
NASA Technical Reports Server (NTRS)
Jones, John H.
2013-01-01
Basalts from the Earth, the Moon, Mars, and Vesta are strongly depleted in elements that prefer to reside in the metallic state (siderophile elements). Therefore, it is believed that all these bodies have metallic cores. We do not yet have siderophile element analyses of venusian or mercurian basalts, but we assume that Venus, too, as a terrestrial planet, has a metallic core. For the Earth, Moon, Mercury, and Mars, the moments-of-inertia of these bodies are consistent with metallic cores of various sizes. Because Venus rotates so slowly, it may be difficult to determine the moment-of-inertia of Venus in order to confirm this assumption. However, despite many possible complexities, it seems likely that most of the major and minor terrestrial planets have experienced some sort of metal/silicate equilibration, and we will use this as a boundary condition. One immediate contrast between the Earth and Moon is the difference in FeO content between lunar and terrestrial basalts. Both bodies presumably formed near 1 AU and formed from the same feeding zone of planetesimals, judging by their oxygen isotopes [13]. If, for example, the Moon formed from the Earth by a giant impact, then this event must have occurred before high-pressure equilibria had the opportunity to deplete the Earth s mantle in FeO. Alternatively, the bulk silicate Moon may be dominated by material from the impactor. Regardless, it would be useful to know the pressures where FeO incorporation into a metallic core is not of interest. If the Giant Impact hypothesis is correct, this should set an upper limit for the size of the proto-Earth at the time of the impact.
NASA Astrophysics Data System (ADS)
McLeod, C. L.; Brown, K.; Brydon, R.; Haley, M.; Hill, T.; Shaulis, B.; Tronnes, R. G.
2017-12-01
Advances in the capabilities of microanalysis over the past several decades have promoted a redefinition of traditional petrological terminology. This has allowed a more accurate evaluation of a samples petrogenetic history. For example, the term "phenocryst", specifically describes crystals that grew from the liquid that solidified into the groundmass. Evolving from this idea is the term xenocryst, referring to crystals that did not originate in the magma but were gathered by it, and antecrysts, which crystallized from a progenitor of the magma that solidified into the groundmass. Through identification of a magmas different, and distinct, crystal populations, the petrogenetic history of a magmatic rock can therefore be unraveled. This approach has been widely applied to terrestrial volcanic systems throughout the past several decades. This study presents results from a combined microimaging and in-situ microanalytical investigation of granitic magmas crystal cargoes in order to unravel how granitic batholiths are constructed. 27 lithological units from two granite batholiths in the Oslo Rift, Norway form the basis of this investigation. Micro X-Ray Fluorescence (µXRF) mapping of major elements and selected trace elements is used in order to chemically map each granitic unit, identify any characteristic growth zoning, and compare the crystal cargoes of the different units. Major and trace elemental abundances of the major phases (feldspars, biotite, amphibole) and minor phases (apatite and titanite) are to be quantified through electron microprobe analysis (EPMA) and laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS) respectively. Through chemically fingerprinting the crystal cargoes of these Oslo Rift granitic magmas, the open vs. closed nature of granitic, intrusive, magmatic systems will be investigated. Within the context of the Oslo Rift, this study also offers an opportunity to evaluate the processes inherent to granitoid magmatism during continental rifting.
Clague, D.A.; Frey, F.A.
1982-01-01
These volcanic rocks are the products of small-volume, late-stage vents along rifts cutting the older massive Koolan tholeiitic shield on Oahu. Most of the lavas and tuffs have the geochemical features expected of near-primary magmas derived from a peridotite source with olivine Fo87-89, e.g. 100 Mg/(Mg + Fe2+) > 65, Ni > 250 p.p.m. and the presence of ultramafic mantle xenoliths at 18 of the 37 vents. Thus the geochemistry of the alkali olivine basalt, basanite, nephelinite and nepheline melilitite lavas and tuffs of these Honolulu volcanic rocks has been used to deduce the composition of their mantle source and the conditions under which they were generated by partial melting in the mantle. New major- and trace-element analyses for 31 samples are tabulated and indicate derivation by partial melting of a garnet (<10%) lherzolite source which was isotopically homogeneous and compositionally uniform for most major and trace elements, though apparently heterogeneous in TiO2, Zr, Hf, Nb and Ta (due perhaps to the low inferred degrees of melting which failed to exhaust the source in minor residual phases). In comparison with estimates of a primordial mantle composition and the mantle source of MORB, the garnet peridotite source of these Honolulu volcanics was increasingly enriched in the sequence heavy REE, Y, Tb, Ti, Sm, Zr and Hf, for which a multi-stage history is required. This composition differs from the source of the previously erupted tholeiitic shield, nor is it represented in the upper-mantle xenoliths in the lavas and tuff of the unit.-R.A.H.
Peltonen-Sainio, Pirjo; Jauhiainen, Lauri; Lehtonen, Heikki
2016-01-01
Diversification of agriculture was one of the strengthened aims of the greening payment of European Agricultural Policy (CAP) as diversification provides numerous ecosystems services compared to cereal-intensive crop rotations. This study focuses on current minor crops in Finland that have potential for expanded production and considers changes in their cropping areas, yield trends, breeding gains, roles in crop rotations and potential for improving resilience. Long-term datasets of Natural Resources Institute Finland and farmers' land use data from the Agency of Rural Affairs were used to analyze the above-mentioned trends and changes. The role of minor crops in rotations declined when early and late CAP periods were compared and that of cereal monocultures strengthened. Genetic yield potentials of minor crops have increased as also genetic improvements in quality traits, although some typical trade-offs with improved yields have also appeared. However, the gap between potential and attained yields has expanded, depending on the minor crop, as national yield trends have either stagnated or declined. When comparing genetic improvements of minor crops to those of the emerging major crop, spring wheat, breeding achievements in minor crops were lower. It was evident that the current agricultural policies in the prevailing market and the price environment have not encouraged cultivation of minor crops but further strengthened the role of cereal monocultures. We suggest optimization of agricultural land use, which is a core element of sustainable intensification, as a future means to couple long-term environmental sustainability with better success in economic profitability and social acceptability. This calls for development of effective policy instruments to support farmer's diversification actions.
Peltonen-Sainio, Pirjo; Jauhiainen, Lauri; Lehtonen, Heikki
2016-01-01
Diversification of agriculture was one of the strengthened aims of the greening payment of European Agricultural Policy (CAP) as diversification provides numerous ecosystems services compared to cereal-intensive crop rotations. This study focuses on current minor crops in Finland that have potential for expanded production and considers changes in their cropping areas, yield trends, breeding gains, roles in crop rotations and potential for improving resilience. Long-term datasets of Natural Resources Institute Finland and farmers’ land use data from the Agency of Rural Affairs were used to analyze the above-mentioned trends and changes. The role of minor crops in rotations declined when early and late CAP periods were compared and that of cereal monocultures strengthened. Genetic yield potentials of minor crops have increased as also genetic improvements in quality traits, although some typical trade-offs with improved yields have also appeared. However, the gap between potential and attained yields has expanded, depending on the minor crop, as national yield trends have either stagnated or declined. When comparing genetic improvements of minor crops to those of the emerging major crop, spring wheat, breeding achievements in minor crops were lower. It was evident that the current agricultural policies in the prevailing market and the price environment have not encouraged cultivation of minor crops but further strengthened the role of cereal monocultures. We suggest optimization of agricultural land use, which is a core element of sustainable intensification, as a future means to couple long-term environmental sustainability with better success in economic profitability and social acceptability. This calls for development of effective policy instruments to support farmer’s diversification actions. PMID:27870865
Parental Consent for Abortion and the Judicial Bypass Option in Arkansas: Effects and Correlates
Joyce, Ted
2010-01-01
CONTEXT In 2005, Arkansas changed its parental notification requirement for minors seeking an abortion to a parental consent law, under which a minor can obtain an abortion without consent after obtaining a judicial waiver. METHODS Using state Department of Health data on 7,463 abortions among 15–19-year-olds over the period 2001–2007, an analysis of abortion and second-trimester abortion rates among Arkansas minors relative to rates among older teenagers evaluated the influence of the 2005 change in the law. Linear and logistic regression analyses estimated the changes in rates among different age-groups, and assessed the likelihood of minors’ using the bypass procedure or having a second-trimester abortion. RESULTS No association was found between the change in the law and either the abortion rate or the second-trimester abortion rate among minors in the state. Ten percent of all abortions among minors were obtained through the judicial bypass procedure, and minors aged 15 or younger who had an abortion were less likely than those aged 17 to get a waiver (odds ratio, 0.2). Minors who used the bypass option were less likely than those who obtained parental consent to have a second-trimester abortion (0.5), and they terminated the pregnancy 1.1 weeks earlier, on average, than did minors who had gotten such consent. CONCLUSIONS States that convert a parental notification statute to a parental consent statute are unlikely to experience a decrease in abortions among minors. PMID:20887286
de Jong, Elisabeth M.; Jellesma, Francine C.; Koomen, Helma M. Y.; de Jong, Peter F.
2016-01-01
Previous research showed that a values-affirmation intervention can help reduce the achievement gap between African American and European American students in the US. In the present study, it was examined if these results would generalize to ethnic minority students in a country outside the US, namely the Netherlands, where there is also an achievement gap between native and ethnic minority students. This type of intervention was tested in two separate studies, the first among first-year pre-vocational students (n = 361, 84% ethnic minority), and the second among sixth grade students (n = 290, 96% ethnic minority). Most minority participants had a Turkish-Dutch or Moroccan-Dutch immigrant background. In the second study, a third condition was added to the original paradigm, in which students elaborated on either their affirmation- or a control exercise with the help of a teaching assistant. We also examined whether values affirmation affected the level of problem behavior of negatively stereotyped ethnic minority youth. Contrary to what was expected, multilevel analyses revealed that the intervention had no effect on the school achievement or the problem behavior of the ethnic minority students. Possible explanations for these findings, mainly related to contextual and cultural differences between the Netherlands and the US, are discussed. PMID:27242604
Woodford, Michael R; Kulick, Alex
2015-03-01
A heterosexist campus climate can increase risk for mental health problems for sexual minority students; however, the relationship between campus climate for sexual minorities and academic outcomes remains understudied. Using a sample of sexual minority respondents extracted from a campus climate survey conducted at a large university in the Midwest, we examine relationships between multiple dimensions of psychological and experiential campus climate for sexual minorities with academic integration (academic disengagement, grade-point average [GPA]) and social integration (institutional satisfaction, acceptance on campus). We also investigate the protective role of engagement with informal academic and peer-group systems. Findings suggest campus climate affects sexual minority students' integration. In multivariate analyses, perceptions of whether lesbian, gay, and bisexual (LGB) people could be open about their sexual identity was positively associated with acceptance on campus; personal heterosexist harassment was positively associated with academic disengagement and negatively with GPA. Students' informal academic integration (instructor relations) and informal social integration (LGB friends) demonstrated influential main effects but did not moderate any of the climate-outcome relationships. Researchers should further explore the relationships between climate and academic outcomes among sexual minority students, both collectively and among specific sub-groups, and address the role of other protective factors.
Discrimination, Mental Health, and Substance Use Disorders Among Sexual Minority Populations
Lee, Ji Hyun; Gamarel, Kristi E.; Bryant, Kendall J.; Zaller, Nickolas D.
2016-01-01
Abstract Purpose: Sexual minority (lesbian, gay, bisexual) populations have a higher prevalence of mental health and substance use disorders compared to their heterosexual counterparts. Such disparities have been attributed, in part, to minority stressors, including distal stressors such as discrimination. However, few studies have examined associations between discrimination, mental health, and substance use disorders by gender among sexual minority populations. Methods: We analyzed data from 577 adult men and women who self-identified as lesbian, gay, or bisexual and participated in Wave 2 of the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC). Six questions assessed discrimination due to sexual orientation. Weighted multivariable logistic regression examined associations between experiences of sexual orientation discrimination and both mental health and substance use disorders. Analyses were conducted separately for sexual minority men and women, adjusting for sociodemographic covariates. Results: Sexual minority men who ever experienced discrimination (57.4%) reported higher odds of any lifetime drug use disorder and cannabis use disorder compared to sexual minority men who never experienced discrimination. Sexual minority women who ever experienced discrimination (42.9%) reported higher odds of any lifetime mood disorder and any lifetime anxiety disorder compared to sexual minority women who never experienced discrimination. Conclusion: The findings suggest that discrimination is differentially associated with internalizing (mental health) and externalizing (substance use) disorders for sexual minority men and women. These findings indicate a need to consider how homophobia and heteronormative discrimination may contribute to distinct health outcomes for lesbian and bisexual women compared with gay and bisexual men. PMID:27383512
Schultz, P. Wesley; Hernandez, Paul R.; Woodcock, Anna; Estrada, Mica; Chance, Randie C.; Aguilar, Maria; Serpe, Richard T.
2013-01-01
For more than 40 years, there has been a concerted national effort to promote diversity among the scientific research community. Yet given the persistent national-level disparity in educational achievements of students from various ethnic and racial groups, the efficacy of these programs has come into question. The current study reports results from a longitudinal study of students supported by a national National Institutes of Health–funded minority training program, and a propensity score matched control. Growth curve analyses using Hierarchical Linear Modeling show that students supported by Research Initiative for Science Excellence were more likely to persist in their intentions to pursue a scientific research career. In addition, growth curve analyses indicate that undergraduate research experience, but not having a mentor, predicted student persistence in science. PMID:24285910
Ufnar, David F.; Ludvigson, Greg A.; Gonzalez, Luis A.; Brenner, Richard L.; Witzke, Brian J.
2004-01-01
Siderite-bearing pedogenic horizons of the Nanushuk Formation of the North Slope, Alaska, provide a critical high paleolatitude oxygen isotopic proxy record of paleoprecipitation, supplying important empirical data needed for paleoclimatic reconstructions and models of "greenhouse-world" precipitation rates. Siderite ??18O values were determined from four paleosol horizons in the National Petroleum Reserve Alaska (NPR-A) Grandstand # 1 Core, and the values range between -17.6??? and -14.3??? Peedee belemnite (PDB) with standard deviations generally less than 0.6??? within individual horizons. The ??13C values are much more variable, ranging from -4.6??? to +10.8??? PDB. A covariant ??18O versus ??13C trend in one horizon probably resulted from mixing between modified marine and meteoric phreatic fluids during siderite precipitation. Groundwater values calculated from siderite oxygen isotopic values and paleobotanical temperature estimates range from -23.0??? to -19.5??? standard mean ocean water (SMOW). Minor element analyses show that the siderites are impure, having enrichments in Ca, Mg, Mn, and Sr. Minor element substitutions and Mg/Fe and Mg/ (Ca + Mg) ratios also suggest the influence of marine fluids upon siderite precipitation. The pedogenic horizons are characterized by gleyed colors, rare root traces, abundant siderite, abundant organic matter, rare clay and silty clay coatings and infillings, some preservation of primary sedimentary stratification, and a lack of ferruginous oxides and mottles. The pedogenic features suggest that these were poorly drained, reducing, hydromorphic soils that developed in coal-bearing delta plain facies and are similar to modern Inceptisols. Model-derived estimates of precipitation rates for the Late Albian of the North Slope, Alaska (485-626 mm/yr), are consistent with precipitation rates necessary to maintain modern peat-forming environments. This information reinforces the mutual consistency between empirical paleotemperature estimates and isotope mass balance models of the hydrologic cycle and can be used in future global circulation modeling (GCM) experiments of "greenhouse-world" climates to constrain high latitude precipitation rates in simulations of ancient worlds with decreased equator-to-pole temperature gradients. ?? 2004 Geological Society of America.
A Model for Determining Strength for Embedded Elliptical Crack in Ultra-high-temperature Ceramics
Wang, Ruzhuan; Li, Weiguo
2015-01-01
A fracture strength model applied at room temperature for embedded elliptical crack in brittle solid was obtained. With further research on the effects of various physical mechanisms on material strength, a thermo-damage strength model for ultra-high-temperature ceramics was applied to each temperature phase. Fracture strength of TiC and the changing trends with elliptical crack shape variations under different temperatures were studied. The study showed that under low temperature, the strength is sensitive to the crack shape variation; as the temperature increases, the sensitivities become smaller. The size of ellipse’s minor axes has great effect on the material strength when the ratio of ellipse’s minor and major axes is lower than 0.5, even under relatively high temperatures. The effect of the minor axes of added particle on material properties thus should be considered under this condition. As the crack area is set, the fracture strength decreases firstly and then increases with the increase of ratio of ellipse’s minor and major axes, and the turning point is 0.5. It suggests that for the added particles the ratio of ellipse’s minor and major axes should not be 0.5. All conclusions significantly coincided with the results obtained by using the finite element software ABAQUS. PMID:28793488
A Model for Determining Strength for Embedded Elliptical Crack in Ultra-high-temperature Ceramics.
Wang, Ruzhuan; Li, Weiguo
2015-08-05
A fracture strength model applied at room temperature for embedded elliptical crack in brittle solid was obtained. With further research on the effects of various physical mechanisms on material strength, a thermo-damage strength model for ultra-high-temperature ceramics was applied to each temperature phase. Fracture strength of TiC and the changing trends with elliptical crack shape variations under different temperatures were studied. The study showed that under low temperature, the strength is sensitive to the crack shape variation; as the temperature increases, the sensitivities become smaller. The size of ellipse's minor axes has great effect on the material strength when the ratio of ellipse's minor and major axes is lower than 0.5, even under relatively high temperatures. The effect of the minor axes of added particle on material properties thus should be considered under this condition. As the crack area is set, the fracture strength decreases firstly and then increases with the increase of ratio of ellipse's minor and major axes, and the turning point is 0.5. It suggests that for the added particles the ratio of ellipse's minor and major axes should not be 0.5. All conclusions significantly coincided with the results obtained by using the finite element software ABAQUS.
Minor actinide transmutation in thorium and uranium matrices in heavy water moderated reactors
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bhatti, Zaki; Hyland, B.; Edwards, G.W.R.
2013-07-01
The irradiation of Th{sup 232} breeds fewer of the problematic minor actinides (Np, Am, Cm) than the irradiation of U{sup 238}. This characteristic makes thorium an attractive potential matrix for the transmutation of these minor actinides, as these species can be transmuted without the creation of new actinides as is the case with a uranium fuel matrix. Minor actinides are the main contributors to long term decay heat and radiotoxicity of spent fuel, so reducing their concentration can greatly increase the capacity of a long term deep geological repository. Mixing minor actinides with thorium, three times more common in themore » Earth's crust than natural uranium, has the additional advantage of improving the sustainability of the fuel cycle. In this work, lattice cell calculations have been performed to determine the results of transmuting minor actinides from light water reactor spent fuel in a thorium matrix. 15-year-cooled group-extracted transuranic elements (Np, Pu, Am, Cm) from light water reactor (LWR) spent fuel were used as the fissile component in a thorium-based fuel in a heavy water moderated reactor (HWR). The minor actinide (MA) transmutation rates, spent fuel activity, decay heat and radiotoxicity, are compared with those obtained when the MA were mixed instead with natural uranium and taken to the same burnup. Each bundle contained a central pin containing a burnable neutron absorber whose initial concentration was adjusted to have the same reactivity response (in units of the delayed neutron fraction β) for coolant voiding as standard NU fuel. (authors)« less
Exploring Ethnic Inequalities in Admission to Russell Group Universities
Boliver, Vikki
2015-01-01
This article analyses national university applications and admissions data to explore why ethnic minority applicants to Russell Group universities are less likely to receive offers of admission than comparably qualified white applicants. Contrary to received opinion, the greater tendency of ethnic minorities to choose highly numerically competitive degree subjects only partially accounts for their lower offer rates from Russell Group universities relative to white applicants with the same grades and ‘facilitating subjects’ at A-level. Moreover, ethnic inequalities in the chances of receiving an admissions offer from a Russell Group university are found to be greater in relation to courses where ethnic minorities make up a larger percentage of applicants. This latter finding raises the possibility that some admissions selectors at some Russell Group universities may be unfairly rejecting a proportion of their ethnic minority applicants in an attempt to achieve a more ethnically representative student body. PMID:27904229
Mobilizing support for the extreme right: a discursive analysis of minority leadership.
Rooyackers, Ilse N; Verkuyten, Maykel
2012-03-01
This study uses a tripolar model of minority influence to investigate social category constructions of extreme right politicians. The analysis focuses on Geert Wilders, leader of the extreme right Party For Freedom (PVV) in the Netherlands. It is examined how this popular politician construes the interdependent relations between himself, the population, and mainstream politicians, and discursively manages his controversial standpoints and proposals. Four parliamentary debates are analysed. The analysis shows that by defining national identity, Wilders invokes a self-image as a prototypical member of the population. Furthermore, and in contrast to other politicians, Wilders works up a self-image of a responsible and realistic politician who is group oriented. In addition, the analysis suggests that being a minority can be of strategic political value and therefore a position to foster. The relevance of the analysis for social psychological approaches to leadership and political minorities is discussed. © 2011 The British Psychological Society.
Sexual Identity Group Differences in Child Abuse and Neglect
Alvy, Lisa M.; Hughes, Tonda L.; Kristjanson, Arlinda F.; Wilsnack, Sharon C.
2013-01-01
Research suggests that sexual minority women are more likely than heterosexual women to report childhood abuse, but little is known about potential within-group variations in experiences of abuse among sexual minority women. We investigated rates and characteristics of childhood sexual and physical abuse among women from five sexual identity groups. Our analyses used a pooled sample of women from a national probability study and a large community-based study of sexual minority women designed to replicate the national study’s methodology (pooled n = 953). As predicted, heterosexual women reported significantly less childhood abuse than did women who identified as mostly heterosexual, bisexual, mostly lesbian, or lesbian. There was also considerable variability in abuse rates and characteristics, including severity of abuse, among sexual minority subgroups. To the extent that differences in reports reflect the actual prevalence and severity of abuse experiences, sexual identity subgroup differences in childhood abuse have important clinical and public health implications. PMID:23345571
Palmer, C.A.; Lyons, P.C.
1990-01-01
Twelve hand-picked vitrinite concentrates and companion whole-coal samples were analyzed for trace and minor elements by instrumental neutron activation analysis (INAA) and direct-current-arc spectrographic techniques (DCAS). The vitrinite concentrates contained 94 to nearly 100 vol.% vitrinite compared to 71-95 vol.% in the companion whole coals. The ash contents of the vitrinite concentrates were 2 to more than 190 times less than the ash contents of the companion whole coals. Organic and inorganic affinities were determined by comparing the elemental concentrations in the vitrinite concentrates to the concentrations in the companion whole coals. The ratios of these concentrations for 33 selected elements are shown in Figure 1. Ratios greater than 1 indicate organic affinity, and ratios less than 1 indicate inorganic affinity. Br and W generally showed organic affinity in all samples in this study. In the nine samples from the eastern United States (Fig. 1A-C) less than one-fourth of the trace elements show organic affinity compared to nearly one-half for the three English and Australian samples (Fig. 1D). The elements that generally show organic affinity in the non-U.S.A. samples studied include As, Cs, Hf, and Ni, which have generally inorganic affinities in the U.S.A. samples, and Cr, Sb, Se, and U, which have mixed (both organic and inorganic) affinities, in the U.S.A. coals studied, has an inorganic affinity in the English coals studied. B shows organic affinity in the samples from the Illinois basin (Fig. 1C). For the samples studied, Ba shows organic affinity in the Appalachian basin bituminous coals (Fig. 1B), inorganic affinity in the Illinois basin coals, and overall mixed affinities. In all the samples studied, Cu, Mn, Na, Sr, Ta, V, and Zn show mixed affinities, and A1, Co, Eu, Fe, Ga, K, La, Mg, Sc, Si, Th, Ti, and Ub have generally inorganic affinity. ?? 1990.
Suicidal ideation in ethnic minority and majority adolescents in Utrecht, the Netherlands.
van Bergen, D D; Smit, J H; van Balkom, A J L M; van Ameijden, E; Saharso, S
2008-01-01
We investigated the prevalence and explored the vulnerability to suicidal ideation across several ethnic minority versus ethnic majority adolescents in the city of Utrecht in The Netherlands. Exploratory analyses were conducted on a dataset obtained from the Municipal Health Services in Utrecht. We examined whether ethnic minority adolescents are at risk for suicidal ideation because of a family background of migration, social-economic position and certain family factors, which influence psychological constellations. We found that levels of suicidal ideation among adolescents of Turkish background were significantly higher than in both majority and other minority adolescents, The Turkish adolescents at risk for suicidal ideation reported that they do not enjoy being at home with their families. Psychological factors, in particular lack of self-pride and the idea of not becoming successful in life, appeared to be important, as well as feelings of loneliness. Suicidal ideation was not found equally across all ethnic minority groups. A history of migration, ethnic minority status, or low socioeconomic status were not sufficient to explain the variation across ethnicities. Our results suggest that specific social-cultural factors, contextualized in the individual and located in the family environment, are relevant in explaining the disproportionate rates for Turkish adolescents in Utrecht.
Evidence of birth-and-death evolution of 5S rRNA gene in Channa species (Teleostei, Perciformes).
Barman, Anindya Sundar; Singh, Mamta; Singh, Rajeev Kumar; Lal, Kuldeep Kumar
2016-12-01
In higher eukaryotes, minor rDNA family codes for 5S rRNA that is arranged in tandem arrays and comprises of a highly conserved 120 bp long coding sequence with a variable non-transcribed spacer (NTS). Initially the 5S rDNA repeats are considered to be evolved by the process of concerted evolution. But some recent reports, including teleost fishes suggested that evolution of 5S rDNA repeat does not fit into the concerted evolution model and evolution of 5S rDNA family may be explained by a birth-and-death evolution model. In order to study the mode of evolution of 5S rDNA repeats in Perciformes fish species, nucleotide sequence and molecular organization of five species of genus Channa were analyzed in the present study. Molecular analyses revealed several variants of 5S rDNA repeats (four types of NTS) and networks created by a neighbor net algorithm for each type of sequences (I, II, III and IV) did not show a clear clustering in species specific manner. The stable secondary structure is predicted and upstream and downstream conserved regulatory elements were characterized. Sequence analyses also shown the presence of two putative pseudogenes in Channa marulius. Present study supported that 5S rDNA repeats in genus Channa were evolved under the process of birth-and-death.
Deformation in Micro Roll Forming of Bipolar Plate
NASA Astrophysics Data System (ADS)
Zhang, P.; Pereira, M.; Rolfe, B.; Daniel, W.; Weiss, M.
2017-09-01
Micro roll forming is a new processing technology to produce bipolar plates for Proton Exchange Membrane Fuel Cells (PEMFC) from thin stainless steel foil. To gain a better understanding of the deformation of the material in this process, numerical studies are necessary before experimental implementation. In general, solid elements with several layers through the material thickness are required to analyse material thinning in processes where the deformation mode is that of bending combined with tension, but this results in high computational costs. This pure solid element approach is especially time-consuming when analysing roll forming processes which generally involves feeding a long strip through a number of successive roll stands. In an attempt to develop a more efficient modelling approach without sacrificing accuracy, two solutions are numerically analysed with ABAQUS/Explicit in this paper. In the first, a small patch of solid elements over the strip width and in the centre of the “pre-cut” sheet is coupled with shell elements while in the second approach pure shell elements are used to discretize the full sheet. In the first approach, the shell element enables accounting for the effect of material being held in the roll stands on material flow while solid elements can be applied to analyse material thinning in a small discrete area of the sheet. Experimental micro roll forming trials are performed to prove that the coupling of solid and shell elements can give acceptable model accuracy while using shell elements alone is shown to result in major deviations between numerical and experimental results.
NASA Astrophysics Data System (ADS)
Ulrich, R. N.; Mergelsberg, S. T.; Dove, P. M.
2016-12-01
Crustacean exoskeletons are a complex biocomposite of organic macromolecules and calcium carbonate minerals. The highly divergent functions and diverse morphologies of these biominerals across taxa raise the question of whether these differences are systematically reflected in exoskeleton composition and structure. Previous studies that investigated element concentrations in exoskeletons used spectroscopic methods. However, the findings were largely inconclusive because of analytical limitations and most studies concluded that magnesium, phosphorus, and other trace elements are mostly contained in the mineral fraction because concentrations in the organic framework could not be resolved. This experimental study was designed to quantify the distributions of Ca, P, Mg, and Sr in the mineral versus organic fractions of exoskeletons from the American Lobster (H. americanus), Dungeness Crab (M. magister), and Red Rock Crab (M. productus). Samples of exoskeleton from 10 body parts were collected in triplicate and dissolved using three procedures specific to extracting the 1) mineral, 2) protein, and 3) chitin phases separately. Chemical analyses of the resulting effluents using ICP-OES show the mineral fraction of the skeleton can contain significant amounts of mineralized Mg and P particularly for body parts associated with a significant difference in mineral structural ordering. The protein fraction contains more Mg and P than expected based on estimates from previous studies (Hild et al., 2008). While the element distributions vary greatly depending on the location, in body parts with thicker cuticle (e.g. claw) the mineral component appears to control overall composition. The findings have implications for paleoenvironmental reconstructions based upon exoskeleton composition. First, the chemical composition of an exoskeleton cannot be assumed constant across the different body parts of an entire organism. This is particularly true when the exoskeleton of the claw is compared to other body parts. We also show a significant fraction of minor and trace elements contained in an exoskeleton are associated with the organic component. Element concentrations obtained from bulk measurements of exoskeletons cannot be assigned to the mineral fraction without imposing a bias on biomineral composition.
Adherence to antiepileptic drugs among diverse older Americans on Part D Medicare.
Piper, Kendra; Richman, Joshua; Faught, Edward; Martin, Roy; Funkhouser, Ellen; Szaflarski, Jerzy P; Dai, Chen; Juarez, Lucia; Pisu, Maria
2017-01-01
Older minority groups are more likely to have poor AED adherence. We describe adherence to antiepileptic drugs (AEDs) among older Americans with epilepsy. In retrospective analyses of 2008-2010 Medicare claims for a 5% random sample of beneficiaries augmented by minority representation, epilepsy cases in 2009 were those with ≥1 claim with ICD-9345.x or ≥2 with 780.3x, and ≥1 AED. New-onset cases had no such claims or AEDs in the year before the 2009 index event. We calculated the Proportion of Days Covered (PDC) (days with ≥1 AED over total follow-up days) and used logistic regression to estimate associations of non-adherence (PDC <0.8) with minority group adjusting for covariates. Of 36,912 epilepsy cases (19.2% White, 62.5% African American (AA), 11.3% Hispanic, 5.0% Asian and 2% American Indian/Alaskan Native), 31.8% were non-adherent (range: 24.1% Whites to 34.3% AAs). Of 3706 new-onset cases, 37% were non-adherent (range: 28.7% Whites to 40.5% AAs). In adjusted analyses, associations with minority group were significant among prevalent cases, and for AA and Asians vs. Whites among new cases. Among other findings, beneficiaries from high-poverty ZIP codes were more likely to be non-adherent than their counterparts, and those in cost-sharing drug benefit phases were less likely to be non-adherent than those in deductible phases. About a third of older adults with epilepsy have poor AED adherence; minorities are more likely than Whites. Investigations of reasons for non-adherence, and interventions to promote adherence, are needed with particular attention to the effect of cost-sharing and poverty. Copyright © 2016 Elsevier Inc. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Murat, Claude; Payen, Thibaut; Petitpierre, Denis
2013-01-01
In the last decade, the genome of several dozen filamentous fungi have been sequenced. Interestingly, vast diversity in genome size was observed (Fig. 2.1) with 14-fold differences between the 9 Mb of the human pathogenic dandruff fungus (Malassezia globosa; Xu, Saunders, et al., 2007) and the 125 Mb of the ectomycorrhizal black truffle of P rigord (Tuber melanosporum; Martin, Kohler, et al., 2010). Recently, Raffaele and Kamoun (2012) highlighted that the genomes of several lineages of filamentous plant pathogens have been shaped by repeat-driven expansion. Indeed, repeated elements are ubiquitous in all prokaryote and eukaryote genomes; however, their frequencies canmore » vary from just a minor percentage of the genome to more that 60 percent of the genome. Repeated elements can be classified in two major types: satellites DNA and transposable elements. In this chapter, the different types of repeated elements and how these elements can impact genome and gene repertoire will be described. Also, an intriguing link between the transposable elements richness and diversity and the ecological niche will be highlighted.« less
Finite element analyses of railroad tank car head impacts
DOT National Transportation Integrated Search
2008-09-24
This paper describes engineering analyses of a railroad : tank car impacted at its head by a rigid punch. This type of : collision, referred to as a head impact, is examined using : dynamic, nonlinear finite element analysis (FEA). : Commercial softw...
Thermal finite-element analysis of space shuttle main engine turbine blade
NASA Technical Reports Server (NTRS)
Abdul-Aziz, Ali; Tong, Michael T.; Kaufman, Albert
1987-01-01
Finite-element, transient heat transfer analyses were performed for the first-stage blades of the space shuttle main engine (SSME) high-pressure fuel turbopump. The analyses were based on test engine data provided by Rocketdyne. Heat transfer coefficients were predicted by performing a boundary-layer analysis at steady-state conditions with the STAN5 boundary-layer code. Two different peak-temperature overshoots were evaluated for the startup transient. Cutoff transient conditions were also analyzed. A reduced gas temperature profile based on actual thermocouple data was also considered. Transient heat transfer analyses were conducted with the MARC finite-element computer code.
ERIC Educational Resources Information Center
Sagebiel, F.; Dahmen, J.
2006-01-01
The paper describes elements of engineering organizational cultures and structures in higher engineering education from the European project WomEng. Hypotheses, based on state of the art, refer to: women friendly presentation, attractiveness of interdisciplinary teaching methods, single sex education, perceptions of minority status, feelings of…
Multi-Cultural Issues In Mental Health Services: Strategies Towards Equity.
ERIC Educational Resources Information Center
California State Dept. of Health, Sacramento.
While California has evolved the elements of a strong and responsive mental health service delivery system based on a statutory partnership among the executive office, local jurisdictions, and citizens, many groups of persons in need of mental health services remain underserved. Such is the plight of the racial/ethnic minority people, whose…
32 CFR 643.122 - Reserve facilities-Air Force and Navy use.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 32 National Defense 4 2010-07-01 2010-07-01 true Reserve facilities-Air Force and Navy use. 643... Force and Navy use. MACOM may approve local agreements with other Army, DOD, and Reserve elements... Force or Navy Reserve, or which involve a transfer of funds between services for other than minor...
ERIC Educational Resources Information Center
Perrine, William M.
2016-01-01
The purpose of this study was to examine potential validity concerns regarding the use of music festival scores as an element of value-added assessment practices mandated by federal education policy. Nonmusical school and band characteristics of band size, school enrollment, school percentage of minority enrollment, and school percentage of…
Different Types of Word Links in the Mental Lexicon
ERIC Educational Resources Information Center
Zhang, Baoguo
2008-01-01
This essay mainly discusses the following issue: Do people from different cultures store English words in their minds in different ways; and what elements determine people's mental lexicon? The findings from my experiment showed that cultural factors only play a minor role on this stage. The leading dominants in this light are the linguistic…