Cl Abundances Research Articles

Melting, Differentiation and Degassing at the Pantelleria Volcano, Italy

We present the results of the first systematic study of melt compositions at Pantelleria, based on both melt inclusions and matrix glasses in pantellerites from 10 eruptions during the last eruptive cycle (<45 kyr). We present major and trace element compositions, as well as data on the volatiles sulphur (S), fluorine (F), chlorine (Cl), water (H2O), carbon dioxide (CO2) and lithium (Li) Rare earth element (REE) compositions were inverted using the program INVMEL to establish the melt fraction vs depth relationship in the Pantellerian mantle source region. Inversion indicates that melts are generated by ∼1·7% melting of a light rare earth element (LREE)-enriched mantle source. The source lies principally within the spinel–garnet transition zone, which, on the basis of trace element ratios, shows some affinity to the source of North African magmatism. Major and trace element data indicate a gap in melt compositions at intermediate compositions, consistent with previously published whole-rock data. This gap rules out the possibility of explaining chemical variability in the Pantelleria lavas merely by changes in the crystal content of the magmas. Principal component analysis of major element glass compositions shows that the liquid line of descent for mafic melt compositions is controlled by clinopyroxene, plagioclase, magnetite and olivine crystallization. Alkali feldspar, clinopyroxene, ilmenite and olivine or aenigmatite crystallization controls the liquid line of descent for the silicic melt compositions, with aenigmatite broadly replacing olivine in the most evolved magmas. Trace element modelling indicates that 96% fractional crystallization is required to generate pantellerites from alkali basalts at Pantelleria (through trachytes, generated after 76% fractional crystallization). We have measured pantellerite volatile concentrations in melt inclusions and in matrix glasses from a variety of eruptions. Melt inclusions, on average, contain 350 ppm S, 3500 ppm F and 9000 ppm Cl. We have measured up to 4·9 wt % H2O and 150 ppm CO2 in melt inclusions. Li–H2O systematics and Cl abundances in melt inclusions are consistent with partitioning of Li and Cl into a subcritical hydrosaline fluid at low pressures. The volatiles H2O and CO2 are used to estimate melt equilibration pressures, which reach a maximum of 1·5 kbar. Temperatures of 800°C are calculated for the most evolved pantellerites, using published feldspar–melt geothermometers, and up to 870°C for the least evolved samples. Low melt viscosities are calculated for the range of pantellerite compositions observed and may account for rapid differentiation by crystal settling. Stable density stratification of the magma chamber is reflected in the eruption of generally progressively more fractionated compositions after the Green Tuff eruption during the last eruptive cycle. Some anomalies in this trend may be explained by variation in the relative rates of eruption vs fractionation. The density stratification is expected to be enhanced and further stabilized by the efficient migration of a fluid phase to the roof of the magma chamber. The sulphur data are used in combination with published experimental partitioning data for peralkaline rhyolites to estimate the sulphur yield to the atmosphere for a large pantelleritic eruption similar to the Green Tuff. This is expected to be markedly higher than for a similar-sized metaluminous rhyolitic or dacitic eruption, mainly owing to the higher bulk sulphur content, lower fluid–melt partition coefficients, and rapid differentiation and vapour phase segregation in the magma chamber.

First experimental results of the 33S(α,p)36Cl cross section for production in the Early Solar System

Short-lived radionuclides (SLRs), with t1/2<∼5Ma, were extant in the Early Solar System (ESS). Their relatively short lifetimes and different chemical behavior make them useful for dating processes in the ESS. The existence of the SLR 36Cl (t1/2=3.01×105a) has been determined from correlation between isotopic enrichment of its daughter isotope, 36S, and Cl abundance in meteorites. The relatively high inferred initial Solar System 36Cl/Cl ratio strongly suggests that 36Cl was produced in the ESS by bombardment of solar energetic particles on gas and dust in the protoplanetary disc. A major uncertainty in the irradiation models is the absence of experimental data. Experimental data on key 36Cl production reactions will help constrain the calculated yields. Of the reactions considered in the ESS models, the 33S(α,p)36Cl reaction is one of the most important. Here we report first results of a measurement of the averaged reaction cross section in the energy range 1.84–2.04MeV/A. Our result, 192±33mb (1σ), is significantly higher than results of previous calculations, 102 and 34mb.

Halogen systematics (Cl, Br, I) in Mid-Ocean Ridge Basalts: A Macquarie Island case study

The abundance of halogens (Cl, Br and I) in the Earth’s mantle has the potential to provide information about mantle metasomatism and volatile recycling in subduction zones. Basalt melts sample different parts of the Earth’s mantle, but few data are available for Br or I in basalt melts, and the relative partitioning behaviour of these elements has not been investigated rigorously. To address these issues, we determined the abundances of Cl, Br and I in enriched Mid-Ocean Ridge Basalt (E-MORB) glasses from Macquarie Island in the southwest Pacific. The Macquarie Island glasses are fairly typical of Pacific MORB with MgO of ∼5.5. to 9wt%, 87Sr/86Sr of 0.70257–0.70276, 143Nd/144Nd of 0.51300–0.51306 and 3He/4He of ∼8Ra. These glasses provide a unique opportunity to investigate halogen partitioning behaviour, because their variable MgO contents and trace element signatures (e.g. La/Sm ∼1.4–7.9) result from different degrees of partial melting and fractional crystallisation.The combined measurement of Br/Cl, I/Cl and K/Cl, together with correlations between Cl and other trace elements, demonstrate that the halogens in the Macquarie Island glasses had a mantle source and were not influenced by seawater contamination. Log–log correlation diagrams indicate that Cl, Br and K were not statistically fractionated during partial melting, crystallisation or degassing of CO2 from these melts. The behaviour of I is less well constrained and minor fractionation of I/Cl cannot be precluded during multi-stage melting and enrichment processes. The data indicate the mantle source of the Macquarie Island glasses was characterised by K/Cl of 13±4, Br/Cl of (3.7±0.5)×10−3 and I/Cl of (130±100)×10−6 (2σ uncertainties; weight ratios). The K/Cl ratio of the Macquarie Island glasses is equivalent to the median of all published MORB data. This suggests the Br/Cl and I/Cl values may also be representative of average MORB mantle values.

THE SOLAR FLARE CHLORINE ABUNDANCE FROM RESIK X-RAY SPECTRA

The abundance of chlorine is determined from X-ray spectra obtained with the RESIK instrument on {\em CORONAS-F} during solar flares between 2002 and 2003. Using weak lines of He-like Cl, \ion{Cl}{16}, between 4.44 and 4.50 \AA, and with temperatures and emission measures from {\em GOES} on an isothermal assumption, we obtained $A({\rm Cl}) = 5.75 \pm 0.26$ on a scale $A({\rm H}) = 12$. The uncertainty reflects an approximately factor 2 scatter in measured line fluxes. Nevertheless our value represents what is probably the best solar determination yet obtained. It is higher by factors of 1.8 and 2.7 than Cl abundance estimates from an infrared sunspot spectrum and nearby \ion{H}{2} regions. The constancy of the RESIK abundance values over a large range of flares ({\em GOES} class from below C1 to X1) argues for any fractionation that may be present in the low solar atmosphere to be independent of the degree of solar activity.

Low abundance of sweat duct Cl- channel CFTR in both healthy and cystic fibrosis athletes with exceptionally salty sweat during exercise.

To understand potential mechanisms explaining interindividual variability observed in human sweat sodium concentration ([Na(+)]), we investigated the relationship among [Na(+)] of thermoregulatory sweat, plasma membrane expression of Na(+) and Cl(-) transport proteins in biopsied human eccrine sweat ducts, and basal levels of vasopressin (AVP) and aldosterone. Lower ductal luminal membrane expression of the Cl(-) channel cystic fibrosis transmembrane conductance regulator (CFTR) was observed in immunofluorescent staining of sweat glands from healthy young adults identified as exceptionally "salty sweaters" (SS) (n = 6, P < 0.05) and from patients with cystic fibrosis (CF) (n = 6, P < 0.005) compared with ducts from healthy young adults with "typical" sweat [Na(+)] (control, n = 6). Genetic testing of healthy subjects did not reveal any heterozygotes ("carriers") for any of the 39 most common disease-causing CFTR mutations in the United States. SS had higher baseline plasma [AVP] compared with control (P = 0.029). Immunostaining to investigate a potential relationship between higher plasma [AVP] (and sweat [Na(+)]) and ductal membrane aquaporin-5 revealed for all groups a relatively sparse and location-dependent ductal expression of the water channel with localization primarily to the secretory coil. Availability of CFTR for NaCl transport across the ductal membrane appears related to the significant physiological variability observed in sweat salt concentration in apparently healthy humans. At present, a heritable link between healthy salty sweaters and the most prevalent disease-causing CFTR mutations cannot be established.

The Potential Feasibility of Chlorinic Photosynthesis on Exoplanets

The modern search for life-bearing exoplanets emphasizes the potential detection of O(2) and O(3) absorption spectra in exoplanetary atmospheres as ideal signatures of biology. However, oxygenic photosynthesis may not arise ubiquitously in exoplanetary biospheres. Alternative evolutionary paths may yield planetary atmospheres tinted with the waste products of other dominant metabolisms, including potentially exotic biochemistries. This paper defines chlorinic photosynthesis (CPS) as biologically mediated photolytic oxidation of aqueous Cl(-) to form halocarbon or dihalogen products, coupled with CO(2) assimilation. This hypothetical metabolism appears to be feasible energetically, physically, and geochemically, and could potentially develop under conditions that approximate the terrestrial Archean. It is hypothesized that an exoplanetary biosphere in which chlorinic photosynthesis dominates primary production would tend to evolve a strongly oxidizing, halogen-enriched atmosphere over geologic time. It is recommended that astronomical observations of exoplanetary outgoing thermal emission spectra consider signs of halogenated chemical species as likely indicators of the presence of a chlorinic biosphere. Planets that favor the evolution of CPS would probably receive equivalent or greater surface UV flux than is produced by the Sun, which would promote stronger abiotic UV photolysis of aqueous halides than occurred during Earth's Archean era and impose stronger evolutionary selection pressures on endemic life to accommodate and utilize halogenated compounds. Ocean-bearing planets of stars with metallicities equivalent to, or greater than, the Sun should especially favor the evolution of chlorinic biospheres because of the higher relative seawater abundances of Cl, Br, and I such planets would tend to host. Directed searches for chlorinic biospheres should probably focus on G0-G2, F, and A spectral class stars that have bulk metallicities of +0.0 Dex or greater.

Primary origin of some trachytoid magmas: Inferences from naturally quenched glasses in hydrothermally metasomatized gabbroic xenoliths (Hyblean area, Sicily)

Hydrothermally-modified gabbroic xenoliths from the Hyblean tuff-breccia deposits (Sicily) consist of albitized plagioclase, Fe–Mg-rich clays, aegirine–augite, ±zeolites, titanite, apatite, magnetite, and hydrothermal zircon. Pockets of silicate glass with perlitic cracking occur in some samples forming 15–20% (by volume) of the rock modal assemblage. Electron microprobe analyses show the trachytic composition of the glass, with generally peralkaline sodic affinity [molar Al2O3/(Na2O+K2O)~0.8 (average value); molar Al2O3/(Na2O+K2O+CaO)~0.7 (average value); Na2O/K2O (wt.%)=1.7–2.3]. The glass trace element abundances, obtained by secondary ion mass spectrometry (SIMS) analyses are consistent with those of world-wide trachytes (e.g. Zr/Ti=0.15–018; Nb/Y=0.73–1). Relatively high abundances of Cl (700–1600 ppm) and F (>500 ppm) were also detected in the glass.Careful macroscopic and microscopic observations exclude the possibility that external silicate melt infiltrated the xenolith. The occurrence of glass pockets between the mafic clay assemblages and the feldspar grains, along with comparisons between chemical compositions of the glass and the surrounding minerals, suggest that the glass is due to the melting of a eutectoid system consisting of Na-rich alkali feldspar, Fe–Mg-rich clays and aegirine–augite. Halogens had probably played an important role in the partial melting process by decreasing the melting temperature of modal minerals, especially feldspar.The occurrence of these trachytic glasses lends support to petrologic models suggesting that partial melting of a hydrothermally altered, brine-rich oceanic crust induced by shallow-seated basic intrusions can produce primary trachytoid melts. This may explain the “Daly-gap” characterizing some oceanic within-plate volcanoes.

Ecological preferences of forest voles

Basic climatic parameters (annual average air temperature and annual amount of precipitation) over 12–25 years have been analyzed with regard to their values corresponding to different levels of abundance in three species of forest voles: Clethrionomys glareolus (in 11 areas of the species range), Cl. rutilus, and Cl. rufocanus (in three areas each). The results show that the abundance of all these species correlates significantly with fluctuations of annual average temperature, with the correlation being negative in Cl. glareolus and Cl. rufocanus but positive in Cl. rutilus. In addition, the abundance of Cl. rufocanus shows a significant correlation with annual precipitation. Voles inhabiting different geographic regions may reach high abundance under different conditions. As for the species range as a whole, however, Cl. glareolus is more ecologically flexible than the other two voles. This species is also more warmth- and moisture-loving, while Cl. rufocanus is more cold-loving and xerophilous, with Cl. rutilus occupying an intermediate position between them. Clethrionomys rutilus is most temperature-dependent and stenothermic among them, whereas Cl. glareolus is indifferent to the factors studied.

The nature of Martian fluids based on mobile element studies in salt‐assemblages from Martian meteorites

The S, Cl, and Br abundances determined in salt assemblages in Nakhla and Lafayette olivine fracturefillings and in gas‐rich impact‐melt (GRIM) glasses from Shergotty and EET79001 Lithologies A &amp; B using EMPA/EDS/APS X‐ray Microprobe techniques are compared with the S and Cl abundances determined by Gooding and coworkers in similar samples using quadrupole mass‐spectrometric techniques. All the analytical methods yield relatively high Cl and low SO3 abundances in Nakhla indicating a SO3/Cl ratio of ∼0.2. The same ratio in Lafayette secondary salts seems to be ∼2. In the case of GRIM glasses from Shergotty and EET79001 Lith A &amp; Lith B, the SO3 abundance is found to be high whereas the Cl abundance is low yielding a SO3/Cl ratio of ∼5–300 (large errors are associated with these ratios because of low Cl signals). The salts found in Nakhla fracturefillings are inferred to have formed from Cl‐rich fluids (high pH) near nakhlite source region on Mars, whereas the secondary minerals found in shergottite GRIM glasses seem to be associated with SO3‐rich fluids (low pH) near shergottite source region on Mars. The Cl‐rich fluids seem to have infiltrated into the nakhlite source region ∼600 Ma ago, whereas the SO3‐rich fluids likely percolated into the shergottite source region at ∼180 Ma (or less) suggesting the possible existence of two types of fluid sources on Mars.

Hydrothermal origin of halogens at Home Plate, Gusev Crater

In the Inner Basin of the Columbia Hills, Gusev Crater is Home Plate, an 80 m platform of layered clastic rocks of the Barnhill class with microscopic and macroscopic textures, including a bomb sag, suggestive of a phreatomagmatic origin. We present data acquired by the Spirit Mars Exploration Rover by Alpha Particle X‐Ray Spectrometer (APXS), Mössbauer Spectrometer, Miniature Thermal Emission Spectrometer (Mini‐TES), and Panoramic Camera (Pancam) for the Barnhill class rocks and nearby vesicular Irvine class basalts. In major element concentrations (e.g., SiO2, Al2O3, MgO, and FeO*), the two rock classes are similar, suggesting that they are derived from a similar magmatic source. The Barnhill class, however, has higher abundances of Cl, Br, Zn, and Ge with comparable SO3 to the Irvine basalts. Nanophase ferric oxide (np ox) and volcanic glass were detected in the Barnhill class rocks by Mössbauer and Mini‐TES, respectively, and imply greater alteration and cooling rates in the Barnhill than in the Irvine class rocks. The high volatile elements in the Barnhill class agree with volcanic textures that imply interaction with a briny groundwater during eruption and (or) by later alteration. Differences in composition between the Barnhill and Irvine classes allow the fingerprinting of a Na‐Mg‐Zn‐Ge‐Cl‐Br (±Fe ± Ca ± CO2) brine with low S. Nearby sulfate salt soils of fumarolic origin may reflect fractionation of an acidic S‐rich vapor during boiling of a hydrothermal brine at depth. Persistent groundwater was likely present during and after the formation of Home Plate.

Regional Probabilistic and Statistical Mineral Potential Mapping of Gold–Silver Deposits Using GIS in the Gangreung Area, Korea

AbstractThe aim of the present study is to analyze relationships between epithermal Au‐Ag deposits of the hydrothermal type and related geological factors and integrate the relationships using probabilistic and statistical models in a geographic information system (GIS) environment. A variety of spatial geological data were compiled, evaluated and integrated to produce a map of potential Au and Ag deposits in the Gangreung area, Korea. This empirical approach assumes that all deposits shared a common genesis. The method consists of three main steps: (i) identification of spatial relationships; (ii) quantification of such relationships and (iii) integration of multiple quantified relationships. A spatial database containing Au and Ag deposits, topographic, geologic, geophysical and geochemical data was constructed using a GIS. The factors relating to 103 Au and Ag mineral deposits are the geological data such as lithology and fault structure, geochemical data including the abundance of Al, As, Ba, Ca, Cd, Co, conductivity, Cr, Cu, Eh, Fe, HCO3–, K, Li, Mg, Mn, Mo, Na, Ni, Pb, pH, Si, Sr, V, W, Zn, Cl−, F−, PO43−, NO2−, NO3− and SO42−, and geophysical data including Bouguer and magnetic anomalies. Using the constructed spatial database, the relationships between mineral deposit areas and 36 related factors are identified and quantified by probabilistic and statistical modeling; that is, likelihood ratio, weights of evidence and logistic regression. All the factors were combined to produce a map of the regional mineral potential using the overlay method in a GIS environment. The mineral potential map was then verified by comparison with known mineral deposits. The verification results give respective accuracies of 82.52%, 72.45% and 81.60% for the likelihood ratio, weights of evidence and logistic regression models, respectively. The mineral potential map can be used as a source of basic information for mineral resource development.

A Multiwavelength Analysis of the Halo Planetary Nebula DdDm‐1

We present new HST optical imagery as well as new UV and IR spectroscopic data obtained with the Hubble Space Telescope and Spitzer Space Telescope, respectively, of the halo planetary nebula DdDm-1. For the first time we present a resolved image of this object, which indicates that the morphology of DdDm-1 can be described as two orthogonal elliptical components in the central part surrounded by an extended halo. The extent of the emission is somewhat larger than was previously reported in the literature. We combine the spectral data with our own previously published optical measurements to derive nebular abundances of He, C, N, O, Ne, Si, S, Cl, Ar, and Fe. The metallicity, as gauged by oxygen, is found to be 0.60 dex below the solar value, confirming DdDm-1's status as a halo PN. In addition, we find that Si and Fe are markedly underabundant, suggesting their depletion onto dust. The very low C/O ratio suggests that the chemistry of the nebula should be consistent with an oxygen-rich environment. With regard to the unexpectedly low S abundance relative to O often seen in PNe, we find that the sulfur abundance of DdDm-1 is only slightly below the value expected based on the normal lockstep behavior between S and O observed in H II regions and blue compact galaxies. We performed a photoionization model analysis from which we inferred a central star effective temperature and luminosity of 55,000 K and 1000 L☉, respectively, implying an initial progenitor mass of <1 M☉. Finally, we report on a new radial velocity determination from echelle observations.

Geochemistry of Martian soil and bedrock in mantled and less mantled terrains with gamma ray data from Mars Odyssey

Surficial materials, including soil and dust, are abundant in the upper tens of centimeters of the Martian surface sensed by the Mars Odyssey Gamma Ray Spectrometer (GRS). Seven large areas (14% of the Martian surface) that represent possible compositional end‐members were selected, including three regions heavily mantled with surficial materials. The selection process included mapping the ratio of exposed rocky terrain to surficial materials using high‐resolution imagery. GRS data for H, Cl, Fe, Si, K, and Th were obtained for each area. The areas are chemically homogeneous within each area, given the spatial resolution and analytical uncertainty of the GRS data. However, substantial chemical differences exist among the areas, including the different mantled terrains, contrary to earlier assumptions that surficial materials are globally homogeneous due to aeolian mixing. The observed chemical differences among the areas may be due to variations in the protolith compositions, extent of alteration of the protolith regions, or post soil formation processes. The abundances of Cl, K, and Th in rockier (but still soil‐rich) areas such as Syrtis Major Planum can be explained by mixing between a soil with higher concentrations of Cl, K, and Th, similar to the abundances in the mantled terrains (and some of the landing sites), and crustal rocks containing lower abundances of these elements, similar to Martian meteorites.

The Localized Chemical Pollution in NGC 5253 Revisited: Results from Deep Echelle Spectrophotometry

WepresentechellespectrophotometryofthebluecompactdwarfgalaxyNGC 5253obtainedwiththeVLTUVES. We have measured the intensities of a large number of permitted and forbidden emission lines in four zones of the centralpartof thegalaxy.Wedetect faint C iiand O iirecombinationlines, thefirsttimethat these areunambiguously detected in a dwarf starburst galaxy. The physical conditions of the ionized gas have been derived using a large number of different line intensity ratios. Chemical abundances of He, N, O, Ne, S, Cl, Ar, and Fe have been determined following standardmethods.C ++ andO ++ abundanceshavebeenderivedfrompurerecombinationlinesand arelargerthanthoseobtainedfromcollisionallyexcitedlines(from0.30to0.40dexforC ++ andfrom0.19to0.28dex for O ++ ). This result is consistent with atemperaturefluctuation parameter (t 2 ) between 0.050 and 0.072. Weconfirm previous results that indicate the presence of a localized N enrichment in certain zones of NGC 5253 and detect a possible slight He overabundance in the same zones. The enrichment pattern agrees with that expected for the pollution by the ejecta of Wolf-Rayet (W-R) stars. The amount of enriched material needed to produce the observed overabundance is consistent with the mass lost by the number of W-R stars estimated in the starbursts. We discuss the possible origin of the difference between abundances derived from recombination and collisionally excited lines (the so-called abundance discrepancy problem) in H ii regions, finding that a recent hypothesis based on the delayed enrichment by SN ejecta inclusions seems not to explain the observed features. Subject headingg galaxies: abundances — galaxies: clusters: individual (NGC 5253) — galaxies: kinematics and dynamics — galaxies: starburst Online material: color figures, machine-readable table

Hydrogeochemistry and Water Balance in the Coastal Wetland Area of “Biviere di Gela,” Sicily, Italy

In the study area physical and chemical factors control the composition of surface and groundwaters, which in turn determine the water quality of the “Biviere di Gela” lake. These factors combine to create diverse water types which change their compositional character spatially as rainfall infiltrates the soil zone, moves down a topographically defined flow path, and interacts with bedrock minerals. Low-salinity waters, which represent the initial stage of underground circulation, start dissolving calcium carbonate from the local rocks. The progressive increase in salinity, characterized by substantially higher Ca, SO4, Na and Cl concentrations, suggests that dissolution of CaSO4 and NaCl is an important process during water–rock interactions. The “Biviere di Gela” lake is often separated into two units (Lago Grande and Lago Piccolo). “Lago Grande” water is generally of Na-SO4-Cl-type, whereas “Lago Piccolo” water is of Na-Cl-SO4-type. Their total content of dissolved salts varies with season, the amount of rainfall, and inflow of ground and drainage water. Over time, an increasing trend towards greater salinity and also sudden changes in the relative abundances of Cl and SO4 have been recorded for the “Lago Grande.” The isotope composition of the lake water appears to be affected by inflow of ground and surface waters and also by evaporative loss. The nitrate content of waters from the recharge basin is of particular concern because it contributes to lake eutrophication. The trace element contents do not evidence the presence of any significant metal contamination of lake waters, although a future potential hazard of metals bioaccumulation by the aquatic biota must be taken into consideration. Finally, a water balance for the basin shows that a drop in precipitation of about 20% might be critical for lake survival.

Regulation of Acid-Base Transporters by Vasopressin in the Kidney Collecting Duct of Brattleboro Rat

Aim: The objective of these studies was to examine the effects of long-term vasopressin treatment on acid-base transporters in the collecting duct of rat kidney. Methods: Brattleboro rats were placed in metabolic cages and treated with daily injections of 1-desamino-8-D-arginine vasopressin (dDAVP), a selective V₂-receptor agonist, or its vehicle (control) for up to 8 days. Results: dDAVP treatment resulted in a significant reduction in serum bicarbonate concentration, and caused the upregulation of key ammoniagenesis enzymes, along with increased urinary NH₄⁺ excretion. Northern hybridization and immunofluorescence labeling indicated a significant increase (+80%) in mRNA expression of the apical Cl^–/HCO₃^– exchanger pendrin (PDS), along with a sharp increase in its protein abundance in B-type intercalated cells in the cortical collecting duct in dDAVP-treated rats. In the inner medullary collecting duct, the abundance of basolateral Cl^–/HCO₃^– exchanger (AE1) and apical H⁺-ATPase was significantly reduced in dDAVP-treated rats. Kidney renin mRNA increased significantly and correlated with an increase in serum aldosterone levels in dDAVP-injected rats. Serum corticosterone levels were, however, reduced and correlated with increased mRNA levels of renal 11β-hydroxysteroid dehydrogenase-2 (11β-HSD2) and decreased mRNA expression of 11β-hydroxylase in the adrenal gland of dDAVP-injected rats. Conclusion: Chronic administration of dDAVP to Brattleboro rats is associated with the upregulation of PDS and downregulation of H⁺-ATPase and AE1 in the collecting duct, along with increased ammoniagenesis. Stimulation of the renin-angiotensin-aldosterone system and/or decreased glucocorticoid levels likely plays a role in the transduction of these effects.

Chemical abundances in seven galactic planetary nebulae

An observational study of chemical abundances in the galactic planetary nebulae NGC 1535, NGC 2438, NGC 2440, NGC 3132, NGC 3242, NGC6302, and NGC 7009 based on long-slit spectra of high signal-to-noise ratio in the 3100 to 6900 A range is presented. We determined the N, O, Ne, S, and Cl abundances from collisionally excited lines and the He and O ++ abundances from recombination lines. The O ++ /H + estimates derived from recombination lines are about a factor of four and two higher than those derived from forbidden lines for NGC 7009 and NGC 3242, respectively. Spatial profiles of O ++ /H + abundance from OII permitted lines and from [OIII] forbidden lines were obtained for the planetary nebula NGC 7009. The differences between O ++ /H + derived from recombination and from forbidden lines present smooth variations along the nebular surface of NGC 7009, with the differences decreasing from the center to the edges of the nebula. If these abundance differences are explained by the presence of electron temperature fluctuations, quantified by the parameter t 2 , a value of about t 2 = 0.09 is required for NGC 3242 and NGC 7009.

The Main Ion Concentrations in Surface Soil Layer in Nam Dinh Province of the Red River Delta, Northern Vietnam

This study aims to clarify the main ion concentrations in paddy field surface soil from 0 to 100cm in depth along the coast of the Red River Delta, Northern Vi etnam, represented by Nam Dinh Province. There is a relation between total dissolved solid (TDS) and Na+concentration. Na+and Cl- concentrations in paddy fields increase gradually and the abundance of Cl- concentration in soil proclaims the influence of seawater intrusion. Washing is reported to reduce the high salinity in the cultivation-layer soil of paddy fields. Furthermore, the impact of seawater intrusion on soil salinity of coastal paddy fields has been considered. The top soil layer of coastal salt-affected paddy fields has the highest sodium absorption ratio (SAR) values, and shows the strongest salinity influence in both the flood season and the dry season. Soil samples near the Day River mouth have high SAR values with considerable Na+ concentrations in the dry season. The exchange selectivity between Ca2+, Mg2+and Na+ has also been studied by considering changes in the SAR under different conditions of soil composition and land cover. In coastal agricultural land, the SAR in the surface soil layer can be used to evaluate the influence of salinity. The SAR in cultivated soil is used to assess the influence of salinity problems on the paddy field.

Sr, Nd, and Pb isotope evidence for a mantle origin of alkali chlorides and carbonates in the Udachnaya kimberlite, Siberia

Research Article| July 01, 2005 Sr, Nd, and Pb isotope evidence for a mantle origin of alkali chlorides and carbonates in the Udachnaya kimberlite, Siberia Roland Maas; Roland Maas 1School of Earth Sciences, University of Melbourne, Parkville, Victoria 3010, Australia, and Max-Planck Institut für Chemie, Mainz 55020, Germany Search for other works by this author on: GSW Google Scholar Maya B. Kamenetsky; Maya B. Kamenetsky 2Centre for Ore Deposit Research, University of Tasmania, Hobart, Tasmania 7001, Australia, and Max-Planck Institut für Chemie, Mainz 55020, Germany Search for other works by this author on: GSW Google Scholar Alexander V. Sobolev; Alexander V. Sobolev 3Max-Planck Institut für Chemie, Mainz 55020, Germany, and Vernadsky Institute of Geochemistry, Moscow 117975, Russia Search for other works by this author on: GSW Google Scholar Vadim S. Kamenetsky; Vadim S. Kamenetsky 4Centre for Ore Deposit Research, University of Tasmania, Hobart, Tasmania 7001, Australia, and Max-Planck Institut für Chemie, Mainz 55020, Germany Search for other works by this author on: GSW Google Scholar Nikolai V. Sobolev Nikolai V. Sobolev 5Institute of Mineralogy and Petrography, Novosibirsk 630090, Russia Search for other works by this author on: GSW Google Scholar Author and Article Information Roland Maas 1School of Earth Sciences, University of Melbourne, Parkville, Victoria 3010, Australia, and Max-Planck Institut für Chemie, Mainz 55020, Germany Maya B. Kamenetsky 2Centre for Ore Deposit Research, University of Tasmania, Hobart, Tasmania 7001, Australia, and Max-Planck Institut für Chemie, Mainz 55020, Germany Alexander V. Sobolev 3Max-Planck Institut für Chemie, Mainz 55020, Germany, and Vernadsky Institute of Geochemistry, Moscow 117975, Russia Vadim S. Kamenetsky 4Centre for Ore Deposit Research, University of Tasmania, Hobart, Tasmania 7001, Australia, and Max-Planck Institut für Chemie, Mainz 55020, Germany Nikolai V. Sobolev 5Institute of Mineralogy and Petrography, Novosibirsk 630090, Russia Publisher: Geological Society of America Received: 03 Oct 2004 Revision Received: 24 Jan 2005 Accepted: 27 Jan 2005 First Online: 02 Mar 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 Geological Society of America Geology (2005) 33 (7): 549–552. https://doi.org/10.1130/G21257.1 Article history Received: 03 Oct 2004 Revision Received: 24 Jan 2005 Accepted: 27 Jan 2005 First Online: 02 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Roland Maas, Maya B. Kamenetsky, Alexander V. Sobolev, Vadim S. Kamenetsky, Nikolai V. Sobolev; Sr, Nd, and Pb isotope evidence for a mantle origin of alkali chlorides and carbonates in the Udachnaya kimberlite, Siberia. Geology 2005;; 33 (7): 549–552. doi: https://doi.org/10.1130/G21257.1 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGeology Search Advanced Search Abstract The kimberlite rocks of the Udachnaya-East pipe (Siberia) are uniquely fresh and contain very high abundances of primary volatiles (Cl, CO2, S). Alkali elements and chlorine are extremely abundant in the reconstructed kimberlite melt compositions, and this enrichment is very important for our understanding of deep-mantle melting and melt transport. Here we present new isotopic data that confirm a mantle origin for these kimberlitic chlorides and carbonates, and constrain the kimberlite emplacement age as ca. 347 Ma. The initial Nd and Pb isotope ratios in a large salt aggregate, in a Cl-S–enriched water leachate of the groundmass, and in the silicate fraction of the groundmass are very similar ( ε Nd = +3 to +4, 206Pb/204Pb = 18.6, 207Pb/204Pb = 15.53), implying a comagmatic origin of the chlorides and carbonates and the silicates. Combined Sr, Nd, and Pb isotope data are used to rule out any significant contributions to the kimberlite chlorine budget from crustal sources, such as the Cambrian evaporite sequences of the Siberian platform. Our data support the interpretation that exsolved Na-K chloride and Na-K-Ca carbonate formed directly from original uncontaminated kimberlite magma. High Cl abundances in kimberlites suggest the presence of a Cl-rich reservoir in the deep sublithospheric mantle. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.

Optical andIUESpectra of the Planetary Nebula NGC 7026

We investigated spectroscopic data of the extended planetary nebula NGC 7026 in the wavelengths 3700-10,050 A, secured with the Hamilton Echelle Spectrograph at Lick Observatory. This optical wavelength spectrum has been analyzed along with the International Ultraviolet Explorer (IUE) UV spectral data. The diagnostic diagram indicates that the planetary nebula has very complex electron densities of N ~ 3000-10,000 cm-3. The electron temperatures are relatively low: around T = 8000-9500 K, probably as a result of an enhanced heavy elemental cooling. The electron temperature variation also indicates that the low-excitation line region is slightly higher than the high-excitation line regions perhaps as a result of the hardening of escaped UV ionizing photons into the outer shell part of low-excitation lines. We construct a photoionization model, with the central star of the planetary nebula at a temperature of Teff = 80,000 K, to fit most of the relatively strong line intensities and the observed physical conditions. With this photoionization model construction and with a semiempirical ionization correction method, we derived the elemental abundances of the nebula. Compared to the average or normal planetary nebula, most elemental abundances of He, C, N, O, Ne, S, Ar, and Cl appear to be enhanced.