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Sample records for acids mono lake

  1. Radionuclides in Mono Lake, California

    SciTech Connect

    Simpson, H.J.; Trier, R.M.; Toggweiler, J.R.; Mathieu, G.; Deck, B.L.; Olsen, C.R.; Hammond, D.E.; Fuller, C.; Ku, T.L.

    1982-04-30

    Several radioisotopes of the naturally occurring uranium and thorium decay series, in addition to fallout plutonium, have unusually high concentrations in the water column of Mono Lake, a natural alkaline, saline lake. Complexing by carbonate ions appears to be responsible for the enhanced solubility of actinide elements with oxidation states of IV to VI. In contrast, fallout strontium-90 has been largely removed from the water, probably as a result of coprecipitation with calcium carbonate. The daughter/parent activity ratios of thorium, radium, and uranium isotopes suggest that thorium is removed from the water column to the sediments on time scales substantially longer than a month and that the desorption of thorium from the sediments to the water column requires less than a few years.

  2. Radionuclides in Mono Lake, California

    SciTech Connect

    Simpson, H.J.; Trier, R.M.; Toggweiler, J.R.; Mathieu, G.; Deck, B.L.; Olsen, C.R.; Hammond, D.E.; Fuller, C.; Ku, T.L.

    1982-04-01

    Several radioisotopes of the naturally occurring uranium and thorium decay series, in addition to fallout plutonium have unusually high concentrations in the water column of Mono Lake, a natural alkaline, saline lake. Complexing by carbonate ions appears to be responsible for the enhanced solubility of actinide elements with oxidation states of IV to VI. In contrast, fallout strontium-90 has been largely removed from the water, probably as a result of coprecipitation with calcium carbonate. The daughter/parent activity ratios of thorium, radium, and uranium isotopes suggest that thorium is removed from the water column to the sediments on time scales substantially longer than a month and that the desorption of thorium from the sediments to the water column requires less than a few years. 2 tables.

  3. 9. GRANT LAKE AND MONO LAKE IN DISTANCE, LOOKING NORTHEAST ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. GRANT LAKE AND MONO LAKE IN DISTANCE, LOOKING NORTHEAST - Los Angeles Aqueduct, From Lee Vining Intake (Mammoth Lakes) to Van Norman Reservoir Complex (San Fernando Valley), Los Angeles, Los Angeles County, CA

  4. Digital Bathymetric Model of Mono Lake, California

    USGS Publications Warehouse

    Raumann, Christian G.; Stine, Scott; Evans, Alexander; Wilson, Jerry

    2002-01-01

    In 1986 and 1987, Pelagos Corporation of San Diego (now Racal Pelagos) undertook a bathymetric survey of Mono Lake in eastern California for the Los Angeles Department of Water and Power (DWP). The result of that survey was a series of maps at various scales and contour intervals. From these maps, the DWP hoped to predict consequences of the drop in lake level that resulted from their diversion of streams in the Mono Basin. No digital models, including shaded-relief and perspective-view renderings, were made from the data collected during the survey. With the permission of Pelagos Corporation and DWP, these data are used to produce a digital model of the floor of Mono Lake. The model was created using a geographic information system (GIS) to incorporate these data with new observations and measurements made in the field. This model should prove to be a valuable tool for enhanced visualization and analyses of the floor of Mono Lake.

  5. Gas exchange on Mono Lake and Crowley Lake, California

    NASA Technical Reports Server (NTRS)

    Wanninkhof, Rik; Ledwell, James R.; Broecker, Wallace S.

    1987-01-01

    Gas exchange coefficients (k) have been determined for freshwater Crowley Lake and saline Mono Lake through the use of a man-made purposefully injected gas, SF6. The concentration decreased from an initial value of 40 to 4 pmol/L for Mono Lake and from 20 to 1 pmol/L for Crowley lake over a period of 6 wks. Wind-speed (u) records from anemometers on the shore of each lake made it possible to determine the relationship between k and u. The average u and k values for the experiment were identical for the two lakes, despite the large chemical differences. It is estimated that, for the u values observed over Mono Lake from July to December 1984, the exchange of CO2 occurred 2.5 times faster than without chemical enhancement. This is a factor of 4 lower than needed to explain the high invasion rate of C-14 produced by nuclear bomb tests.

  6. Gaylussite formation at mono lake, california

    USGS Publications Warehouse

    Bischoff, J.L.; Herbst, D.B.; Rosenbauer, R.J.

    1991-01-01

    The salinity of Mono Lake has steadily increased since 1941 from 50%. to about 90%. due to diversion of tributary streams. This increase has resulted in the newly discovered precipitation of gaylussite (Na2Ca(CO3)2 ?? 5H2O). Chemical modeling of the lake water using Pitzer equations suggests that gaylussite has been forming year round since about 1970 when the salinity first exceeded 80%., and that it was earlier forming intermittently at lower salinities in the winter shortly after diversion began, breaking down incongruently to aragonite during summers. Lake water appears to remain at a constant 9-fold supersaturation with aragonite at all salinities, perhaps buffered by monohydrocalcite which appears to be just at saturation for all salinities. Other saline lakes also appear to be buffered by monohydrocalcite. ?? 1991.

  7. Gaylussite formation at Mono Lake, California

    SciTech Connect

    Bischoff, J.L.; Rosenbauer, R.J. ); Herbst, D.B. )

    1991-06-01

    The salinity of Mono Lake has steadily increased since 1941 from 50{per thousand} to about 90{per thousand} due to diversion of tributary streams. This increase has resulted in the newly discovered precipitation of gaylussite (Na{sub 2}Ca(CO{sub 3}){sub 2} {center dot} 5H{sub 2}O). Chemical modeling of the lake water using Pitzer equations suggests that gaylussite has been forming year round since about 1970 when the salinity first exceeded 80{per thousand}, and that it was earlier forming intermittently at lower salinities in the winter shortly after diversion began, breaking down incongruently to aragonite during summers. Lake water appears to remain at a constant 9-fold supersaturation with aragonite at all salinities, perhaps buffered by monohydrocalcite which appears to be just at saturation for all salinities. Other saline lakes also appear to be buffered by monohydrocalcite.

  8. Elevated concentrations of actinides in Mono Lake

    SciTech Connect

    Anderson, R.F.; Bacon, M.P.; Brewer, P.G.

    1982-04-30

    Tetravalent thorium, pentavalent protactinium, hexavalent uranium, and plutonium (oxidation state uncertain) are present in much higher concentrations in Mono Lake, a saline, alkaline lake in eastern central California, than in seawater. Low ratios of actinium to protactinium and of americium to plutonium indicate that the concentrations of trivalent actinides are not similarly enhanced. The elevated concentrations of the ordinarily very insoluble actinides are maintained in solution by natural ligands, which inhibit their chemical removal from the water column, rather than by an unusually large rate of supply.

  9. Elevated concentrations of actinides in mono lake.

    PubMed

    Anderson, R F; Bacon, M P; Brewer, P G

    1982-04-30

    Tetravalent thorium, pentavalent protactinium, hexavalent uranium, and plutonium (oxidation state uncertain) are present in much higher concentrations in Mono Lake, a saline, alkaline lake in eastern central California, than in seawater. Low ratios of actinium to protactinium and of americium to plutonium indicate that the concentrations of trivalent actinides are not similarly enhanced. The elevated concentrations of the ordinarily very insoluble actinides are maintained in solution by natural ligands, which inhibit their chemical removal from the water column, rather than by an unusually large rate of supply.

  10. 1. LEE VINING INTAKE LOOKING EAST TO MONO LAKE. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. LEE VINING INTAKE LOOKING EAST TO MONO LAKE. - Los Angeles Aqueduct, From Lee Vining Intake (Mammoth Lakes) to Van Norman Reservoir Complex (San Fernando Valley), Los Angeles, Los Angeles County, CA

  11. 2. LEE VINING INTAKE, MONO LAKE IN BACKGROUND. Los ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. LEE VINING INTAKE, MONO LAKE IN BACKGROUND. - Los Angeles Aqueduct, From Lee Vining Intake (Mammoth Lakes) to Van Norman Reservoir Complex (San Fernando Valley), Los Angeles, Los Angeles County, CA

  12. Mono Lake earthquake of October 23, 1990

    SciTech Connect

    McNutt, S.; Bryant, W.; Wilson, R.

    1991-02-01

    On October 23, 1990, a moderate earthquake of local magnitude (M{sub L}) 5.7 shook the Mono Lake area, a region known for its recent volcanic and tectonic activity. The earthquake was centered approximately 5 miles north of Lee Vining and 16 miles southeast of Bridgeport, near Black Point, an isolated flat-topped hill on the north shore of Mono Lake. Shaking from the earthquake was felt at approximately Modified Mercalli Intensity VI in the local area and weakly throughout much of north central California as far west as Sacramento and the San Francisco Bay area. This article summarizes the seismological features of the earthquake and relates the findings made during a surface fault rupture investigation of epicentral area by Division of Mines and Geology (DMG) geologists. To demonstrate how this earthquake fits into the regional tectonic setting, the character of this event is compared to that of other noteworthy seismic events that have occurred over the last 12 years.

  13. 11. GRANT LAKE AND MONO LAKE LOOKING NORTH/NORTHEAST Los ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    11. GRANT LAKE AND MONO LAKE LOOKING NORTH/NORTHEAST - Los Angeles Aqueduct, From Lee Vining Intake (Mammoth Lakes) to Van Norman Reservoir Complex (San Fernando Valley), Los Angeles, Los Angeles County, CA

  14. 10. GRANT LAKE AND MONO LAKE LOOKING EAST/NORTHEAST Los ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. GRANT LAKE AND MONO LAKE LOOKING EAST/NORTHEAST - Los Angeles Aqueduct, From Lee Vining Intake (Mammoth Lakes) to Van Norman Reservoir Complex (San Fernando Valley), Los Angeles, Los Angeles County, CA

  15. Plutonium speciation in water from Mono Lake, California

    USGS Publications Warehouse

    Cleveland, J.M.; Rees, T.F.; Nash, K.L.

    1983-01-01

    The solubility of plutonium in Mono Lake water is enhanced by the presence of large concentrations of indigenous carbonate ions and moderate concentrations of fluoride ions. In spite of the complex chemical composition of this water, only a few ions govern the behavior of plutonium, as demonstrated by the fact that it was possible to duplicate plutonium speciation in a synthetic water containing only the principal components of Mono Lake water.

  16. Plutonium speciation in water from Mono Lake, California

    SciTech Connect

    Cleveland, J.M.; Rees, T.F.; Nash, K.L.

    1983-12-23

    The solubility of plutonium in Mono Lake water is enhanced by the presence of large concentrations of indigenous carbonate ions and moderate concentrations of fluoride ions. In spite of the complex chemical composition of this water, only a few ions govern the behavior of plutonium, as demonstrated by the fact that it was possible to duplicate plutonium speciation in a synthetic water containing only the principal components of Mono Lake water.

  17. Geophysical studies of Mono Lake, east-central California

    NASA Astrophysics Data System (ADS)

    Athens, N. D.; Ponce, D. A.

    2012-12-01

    Magnetic and gravity investigations were undertaken in Mono Lake, California to study regional crustal structures and to aid understanding the geologic framework of Mono Lake, in particular regarding potential geothermal resources and volcanic hazards throughout Mono Basin. Recent geophysical surveys included over 600 line-kilometers of high-resolution ship-borne magnetometer data that augmented existing airborne data, 22 line-kilometers of ground magnetic data that were collected along six traverses across Paoha Island, 56 gravity stations that were collected on Paoha and Negit Islands, and 28 rock samples that were collected for physical property data. Magnetic highs in the study area occur to the east and west of Mono Lake, where pre-Tertiary basement is exposed. Magnetic data indicate that Mono Lake itself is dominated by three prominent magnetic anomalies that are from west to east: a magnetic high along the northwest part of the lake associated with the moderately magnetic basalt cinder cone at Black Point, a magnetic high associated with the young volcanic centers at Paoha and Negit Islands, and a broad magnetic high along the eastern margin of the lake probably associated with moderately magnetic granitic basement rocks at depth. Because volcanic rocks exposed at the surface of Paoha and Negit Islands are only weakly magnetic, magnetic data suggest that more mafic volcanic rocks probably occur at depth and are the source of the anomaly. The linear and steep magnetic gradient across the eastern part of the lake may reflect a fault. A fault may also be imaged in the northeastern part of the lake, where a possible laterally offset magnetic anomaly may be present. Within Mono Lake, gravity station control is poor because land-based gravity stations are limited to Paoha and Negit Islands. The gravity low in the basin reflects a moderately deep sedimentary basin filled with low density lacustrine and volcanic deposits. Isostatic gravity data indicate the central

  18. Nongeocentric axial dipole field behavior during the Mono Lake excursion

    NASA Astrophysics Data System (ADS)

    Negrini, Robert M.; McCuan, Daniel T.; Horton, Robert A.; Lopez, James D.; Cassata, William S.; Channell, James E. T.; Verosub, Kenneth L.; Knott, Jeffrey R.; Coe, Robert S.; Liddicoat, Joseph C.; Lund, Steven P.; Benson, Larry V.; Sarna-Wojcicki, Andrei M.

    2014-04-01

    A new record of the Mono Lake excursion (MLE) is reported from the Summer Lake Basin of Oregon, USA. Sediment magnetic properties indicate magnetite as the magnetization carrier and imply suitability of the sediments as accurate recorders of the magnetic field including relative paleointensity (RPI) variations. The magnitudes and phases of the declination, inclination, and RPI components of the new record correlate well with other coeval but lower resolution records from western North America including records from the Wilson Creek Formation exposed around Mono Lake. The virtual geomagnetic pole (VGP) path of the new record is similar to that from another high-resolution record of the MLE from Ocean Drilling Program (ODP) Site 919 in the Irminger Basin between Iceland and Greenland but different from the VGP path for the Laschamp excursion (LE), including that found lower in the ODP-919 core. Thus, the prominent excursion recorded at Mono Lake, California, is not the LE but rather one that is several thousands of years younger. The MLE VGP path contains clusters, the locations of which coincide with nonaxial dipole features found in the Holocene geomagnetic field. The clusters are occupied in the same time progression by VGPs from Summer Lake and the Irminger Basin, but the phase of occupation is offset, a behavior that suggests time-transgressive decay and return of the principal field components at the beginning and end of the MLE, respectively, leaving the nonaxial dipole features associated with the clusters dominant during the excursion.

  19. Mono Lake Analog Mars Sample Return Expedition for AMASE

    NASA Technical Reports Server (NTRS)

    Conrad, P. G.; Steele, A.; Younse, P.; DiCicco, M.; Morgan, A. R.; Backes, P.; Eigenbrode, J. E.; Marquardt, D.; Amundsen, H. E. F.

    2011-01-01

    We explored the performance of one robotic prototype for sample acquisition and caching of martian materials that has been developed at the Jet Propulsion Laboratory for potential use in the proposed MAX-C Mars Sample Return architecture in an environment, rich in chemical diversity with a variety of mineralogical textures. Mono Lake State Tufa Reserve in Mono County, CA possesses a variety of minerals including a variety of evaporites, volcanic glass and lava, and sand and mudstones. The lake itself is an interesting chemical system: the water is highly alkaline (pH is approximately 10) and contains concentrations of Cl, K, B, with lesser amounts of S Ca Mg, F, As, Li, I and Wand generally enriched HREEs. There are also traces of radioactive elements U, Th, Pl.

  20. Bacterial oxidation of methyl bromide in Mono Lake, California

    USGS Publications Warehouse

    Connell, T.L.; Joye, S.B.; Miller, L.G.; Oremland, R.S.

    1997-01-01

    The oxidation of methyl bromide (MeBr) in the water column of Mono Lake, CA, was studied by measuring the formation of H14CO3 from [14C]MeBr. Potential oxidation was detected throughout the water column, with highest rates occurring in the epilimnion (5-12 m depth). The oxidation of MeBr was eliminated by filter-sterilization, thereby demonstrating the involvement of bacteria. Vertical profiles of MeBr activity differed from those obtained for nitrification and methane oxidation, indicating that MeBr oxidation is not simply a co-oxidation process by either nitrifiers or methanotrophs. Furthermore, specific inhibitors of methane oxidation and/or nitrification (e.g., methyl fluoride, acetylene, allyl sulfide) had no effect upon the rate of MeBr oxidation in live samples. Of a variety of potential electron donors added to Mono Lake water, only trimethylamine resulted in the stimulation of MeBr oxidation. Cumulatively, these results suggest that the oxidation of MeBr in Mono Lake waters is attributable to trimethylamine-degrading methylotrophs. Neither methyl chloride nor methanol inhibited the oxidation of [14C]MeBr in live samples, indicating that these bacteria directly oxidized MeBr rather than the products of MeBr nucleophilic substitution reactions.

  1. Age of the Mono Lake excursion and associated tephra

    USGS Publications Warehouse

    Benson, L.; Liddicoat, J.; Smoot, J.; Sarna-Wojcicki, A.; Negrini, R.; Lund, S.

    2003-01-01

    The Mono Lake excursion (MLE) is an important time marker that has been found in lake and marine sediments across much of the Northern Hemisphere. Dating of this event at its type locality, the Mono Basin of California, has yielded controversial results with the most recent effort concluding that the MLE may actually be the Laschamp excursion (Earth Planet. Sci. Lett. 197 (2002) 151). We show that a volcanic tephra (Ash #15) that occurs near the midpoint of the MLE has a date (not corrected for reservoir effect) of 28,620 ?? 300 14C yr BP (??? 32,400 GISP2 yr BP) in the Pyramid Lake Basin of Nevada. Given the location of Ash #15 and the duration of the MLE in the Mono Basin, the event occurred between 31,500 and 33,300 GISP2 yr BP, an age range consistent with the position and age of the uppermost of two paleointensity minima in the NAPIS-75 stack that has been associated with the MLE (Philos. Trans. R. Soc. London Ser. A 358 (2000) 1009). The lower paleointensity minimum in the NAPIS-75 stack is considered to be the Laschamp excursion (Philos. Trans. R. Soc. London Ser. A 358 (2000) 1009).

  2. Assessing Ecological Impact Assessment: Lessons from Mono Lake, California.

    PubMed

    Wiens, John A; Patten, Duncan T; Botkin, Daniel B

    1993-11-01

    Because of its high salinity and alkalinity, Mono Lake, in eastern California (USA), is a relatively simple ecosystem. It has become the focus of an environmental controversy over the effects of 50 yr of diversions of water from tributary streams to supply water to Los Angeles. Diversions lowered the lake level, increased the salinity, changed the availability of aquatic habitats, and altered the configuration of the shoreline and of islands that support breeding colonies of gulls. We consider (1) how two independent panels of experts synthesized scientific information on the lake ecosystem to assess the environmental consequences of these changes, and (2) how the findings of these groups influenced policy decisions and how well subsequent changes in the lake matched expectations. Despite differences in composition and approach, the two panels reached generally similar conclusions. These conclusions have been a major component of legal activities and the development of management plans for the lake and basin ecosystem. Both panels concluded that, because of the simplicity of the lake ecosystem, ecological consequences of changes in lake level and salinity associated with continuing diversions were likely to be unusually clear-cut. At certain lake levels these changes would be expected to alter algal and invertebrate populations and the populations of aquatic birds that feed upon them or to disrupt breeding activities in gull colonies. Projections about when critical lake levels might be reached, however, have not been met. This is largely because stream flows into the lake have been altered from recent historic patterns by the cessation of water diversions due to governmental and legal actions (prompted in part by the panels' findings) and by a prolonged drought. These events illustrate the difficulty of projecting a timetable for environmental changes, even in simple and well-studied ecosystems.

  3. The microbial arsenic cycle in Mono Lake, California.

    PubMed

    Oremland, Ronald S; Stolz, John F; Hollibaugh, James T

    2004-04-01

    Significant concentrations of dissolved inorganic arsenic can be found in the waters of a number of lakes located in the western USA and in other water bodies around the world. These lakes are often situated in arid, volcanic terrain. The highest concentrations of arsenic occur in hypersaline, closed basin soda lakes and their remnant brines. Although arsenic is a well-known toxicant to eukaryotes and prokaryotes alike, some prokaryotes have evolved biochemical mechanisms to exploit arsenic oxyanions (i.e., arsenate and arsenite); they can use them either as an electron acceptor for anaerobic respiration (arsenate), or as an electron donor (arsenite) to support chemoautotrophic fixation of CO(2) into cell carbon. Unlike in freshwater or marine ecosystems, these processes may assume quantitative significance with respect to the carbon cycle in arsenic-rich soda lakes. For the past several years our research has focused on the occurrence and biogeochemical manifestations of these processes in Mono Lake, a particularly arsenic-rich environment. Herein we review some of our findings concerning the biogeochemical arsenic cycle in this lake, with the hope that it may broaden the understanding of the influence of microorganisms upon the speciation of arsenic in more common, less "extreme" environments, such as drinking water aquifers.

  4. The microbial arsenic cycle in Mono Lake, California

    USGS Publications Warehouse

    Oremland, Ronald S.; Stolz, John F.; Hollibaugh, James T.

    2004-01-01

    Significant concentrations of dissolved inorganic arsenic can be found in the waters of a number of lakes located in the western USA and in other water bodies around the world. These lakes are often situated in arid, volcanic terrain. The highest concentrations of arsenic occur in hypersaline, closed basin soda lakes and their remnant brines. Although arsenic is a well-known toxicant to eukaryotes and prokaryotes alike, some prokaryotes have evolved biochemical mechanisms to exploit arsenic oxyanions (i.e., arsenate and arsenite); they can use them either as an electron acceptor for anaerobic respiration (arsenate), or as an electron donor (arsenite) to support chemoautotrophic fixation of CO2 into cell carbon. Unlike in freshwater or marine ecosystems, these processes may assume quantitative significance with respect to the carbon cycle in arsenic-rich soda lakes. For the past several years our research has focused on the occurrence and biogeochemical manifestations of these processes in Mono Lake, a particularly arsenic-rich environment. Herein we review some of our findings concerning the biogeochemical arsenic cycle in this lake, with the hope that it may broaden the understanding of the influence of microorganisms upon the speciation of arsenic in more common, less “extreme” environments, such as drinking water aquifers.

  5. The radiocarbon budget for Mono Lake: an unsolved mystery

    USGS Publications Warehouse

    Broecker, W.S.; Wanninkhof, R.; Mathieu, G.; Peng, T.-H.; Stine, S.; Robinson, S.; Herczeg, A.; Stuiver, M.

    1988-01-01

    Since 1957 the 14C C ratio of the dissolved inorganic carbon in Mono Lake has risen by about 60???. The magnitude of this increase is about four times larger than that expected from the invasion of bomb-produced 14C from the atmosphere. We have eliminated the following explanations: (1) measurement error, (2) an unusually high physical exchange rate for non-reactive gases, (3) inorganic enhancement of the CO2 exchange rate, and (4) biological enhancement of the CO2 exchange rate. Clandestine disposal of waste radiocarbon remains a dark-horse explanation. In the course of our investigations we have uncovered evidence for at least one episodic input of radiocarbon-free carbon to the lake over the last 1000 years. We speculate that this injection was related to a hydrothermal event resulting from sublacustrine volcanic activity. ?? 1988.

  6. Selenate-dependent anaerobic arsenite oxidation by a bacterium from Mono Lake, California.

    PubMed

    Fisher, Jenny C; Hollibaugh, James T

    2008-05-01

    Arsenate was produced when anoxic Mono Lake water samples were amended with arsenite and either selenate or nitrate. Arsenite oxidation did not occur in killed control samples or live samples with no added terminal electron acceptor. Potential rates of anaerobic arsenite oxidation with selenate were comparable to those with nitrate ( approximately 12 to 15 mumol.liter(-1) h(-1)). A pure culture capable of selenate-dependent anaerobic arsenite oxidation (strain ML-SRAO) was isolated from Mono Lake water into a defined salts medium with selenate, arsenite, and yeast extract. This strain does not grow chemoautotrophically, but it catalyzes the oxidation of arsenite during growth on an organic carbon source with selenate. No arsenate was produced in pure cultures amended with arsenite and nitrate or oxygen, indicating that the process is selenate dependent. Experiments with washed cells in mineral medium demonstrated that the oxidation of arsenite is tightly coupled to the reduction of selenate. Strain ML-SRAO grows optimally on lactate with selenate or arsenate as the electron acceptor. The amino acid sequences deduced from the respiratory arsenate reductase gene (arrA) from strain ML-SRAO are highly similar (89 to 94%) to those from two previously isolated Mono Lake arsenate reducers. The 16S rRNA gene sequence of strain ML-SRAO places it within the Bacillus RNA group 6 of gram-positive bacteria having low G+C content.

  7. Sources and flux of natural gases from Mono lake, California

    SciTech Connect

    Oremland, R.S.; Miller, L.G. ); Whiticar, M.J. )

    1987-11-01

    The ability to identify a formation mechanism for natural gas in a particular environment requires consideration of several geochemical factors when there are multiple sources present. Four primary sources of methane have been identified in Mono Lake. Two of these sources were associated with numerous natural gas seeps which occur at various locations in the lake and extend beyond its present boundary; the two other gas sources result from current microbiological processes. Current microbiological processes responsible for sources of natural gas in the lake included pelagic methanogenesis and decomposition of terrestrial grasses in the littoral zone. Methanogenesis in the pelagic sediments resulted in methane saturation. Interstitial sulfate decreased from 133 mM at the surface to 35 mM by 110 cm depth, indicating that sulfate-reduction and methanogenesis operated concurrently. Methane diffused out of the sediments resulting in concentrations of about 50 {mu}M in the anoxic bottom waters. Methane oxidation in the oxic/anoxic boundary lowered the concentration by > 98%, but values in surface waters were supersaturated with respect to the atmosphere. The {delta}{sup 13}CH{sub 4} of this unoxidized residual methane was enriched in {sup 13}C relative to methane in the bottom water and sediments. Average outward flux of this methane was 2.77 {times} 10{sup 7} moles yr{sup {minus}1}. A fourth, but minor source of methane was associated with the decomposition of terrestrial grasses taking place in the lake's recently expanded littoral zone.

  8. Ca isotope fractionation in a high-alkalinity lake system: Mono Lake, California

    NASA Astrophysics Data System (ADS)

    Nielsen, Laura C.; DePaolo, Donald J.

    2013-10-01

    Precipitation of calcium carbonate minerals from aqueous solutions causes surface-controlled kinetic stable Ca isotope fractionation. The magnitude of fractionation depends on the relative rates of ion attachment to and detachment from the mineral surface, which in turn is predicted to depend on both the saturation state and the solution stoichiometry or the Ca:CO32- activity ratio. Experimental studies have not directly investigated the effects of varying solution stoichiometry on calcium isotope partitioning during calcite or aragonite growth, but natural alkaline lake systems such as Mono Lake, California provide a test bed for the hypothesized stoichiometry dependence. Mono Lake has a Ca:CO32- activity ratio of about 0.0001, seven orders of magnitude lower than ocean water and typical terrestrial freshwater. We present chemical and isotopic measurements of streams, springs, lake water, and precipitated carbonates from the Mono Basin that yield evidence of stoichiometry-dependent Ca isotope fractionation during calcite, aragonite and Mg-calcite precipitation from the alkaline lake water. To estimate the Ca isotope fractionation factors, it is necessary to characterize the lake Ca balance and constrain the variability of lake water chemistry both spatially and temporally. Streams and springs supply Ca to the lake, and a substantial fraction of this supply is precipitated along the lake shore to form tufa towers. Lake water is significantly supersaturated with respect to carbonate minerals, so CaCO3 also precipitates directly from the water column to form carbonate-rich bottom sediments. Growth rate inhibition by orthophosphate likely preserves the high degree of supersaturation in the lake. Strontium isotope ratios are used to estimate the proportions of fresh and alkaline lake water from which each solid carbonate sample precipitated. Carbonate minerals that precipitate directly from lake water (low Ca:CO32-) experience relatively large Ca isotope fractionation

  9. Balancing Public Trust Resources of Mono Lake and Los Angeles' Water Right: An Economic Approach

    NASA Astrophysics Data System (ADS)

    Loomis, John B.

    1987-08-01

    The contingent valuation method (CVM) is used to quantify the Public Trust values of Mono Lake at alternative lake levels. The dichotomous choice approach to contingent valuation is employed using a logit model. The economic benefit to California residents of preserving Mono Lake is estimated to be 1.5 billion. Purchase of replacement water and power would cost 26.2 million annually. On efficiency grounds, reallocation of water for maintenance of Public Trust values at Mono Lake is warranted. The CVM appears to be a useful methodology to evaluate the balancing and feasibility tests of the expanded Public Trust doctrine suggested by the California Supreme Court.

  10. Magnetic and gravity studies of Mono Lake, east-central, California

    USGS Publications Warehouse

    Athens, Noah D.; Ponce, David A.; Jayko, Angela S.; Miller, Matt; McEvoy, Bobby; Marcaida, Mae; Mangan, Margaret T.; Wilkinson, Stuart K.; McClain, James S.; Chuchel, Bruce A.; Denton, Kevin M.

    2014-01-01

    From August 26 to September 5, 2011, the U.S. Geological Survey (USGS) collected more than 600 line-kilometers of shipborne magnetic data on Mono Lake, 20 line-kilometers of ground magnetic data on Paoha Island, 50 gravity stations on Paoha and Negit Islands, and 28 rock samples on Paoha and Negit Islands, in east-central California. Magnetic and gravity investigations were undertaken in Mono Lake to study regional crustal structures and to aid in understanding the geologic framework, in particular regarding potential geothermal resources and volcanic hazards throughout Mono Basin. Furthermore, shipborne magnetic data illuminate local structures in the upper crust beneath Mono Lake where geologic exposure is absent. Magnetic and gravity methods, which sense contrasting physical properties of the subsurface, are ideal for studying Mono Lake. Exposed rock units surrounding Mono Lake consist mainly of Quaternary alluvium, lacustrine sediment, aeolian deposits, basalt, and Paleozoic granitic and metasedimentary rocks (Bailey, 1989). At Black Point, on the northwest shore of Mono Lake, there is a mafic cinder cone that was produced by a subaqueous eruption around 13.3 ka. Within Mono Lake there are several small dacite cinder cones and flows, forming Negit Island and part of Paoha Island, which also host deposits of Quaternary lacustrine sediments. The typical density and magnetic properties of young volcanic rocks contrast with those of the lacustrine sediment, enabling us to map their subsurface extent.

  11. Organic osmolytes in aerobic bacteria from mono lake, an alkaline, moderately hypersaline environment.

    PubMed

    Ciulla, R A; Diaz, M R; Taylor, B F; Roberts, M F

    1997-01-01

    The identity and concentrations of intracellular organic solutes were determined by nuclear magnetic resonance spectroscopy for two strains of aerobic, gram-negative bacteria isolated from Mono Lake, Calif., an alkaline, moderately hypersaline lake. Ectoine (1,4,5,6-tetrahydro-2-methyl-4-pyrimidinecarboxylic acid) was the major endogenous solute in both organisms. Concentrations of ectoine varied with external NaCl levels in strain ML-D but not in strain ML-G, where the level was high but invariant from 1.5 to 3.0 M NaCl. Hydroxyectoine also occurred in strain ML-D, especially at elevated NaCl concentrations (2.5 and 3.0 M), but at levels lower than those of ectoine. Exogenous organic solutes that might occur in Mono Lake were examined for their effects on the de novo synthesis of ectoine. Dimethylsulfoniopropionate (DMSP) (0.1 or 1 mM) did not significantly lower ectoine levels in either isolate, and only strain ML-G showed any capacity for DMSP accumulation. With nitrogen limitation, however, DMSP (0.1 mM) substituted for ectoine in strain ML-G and became the main organic solute. Glycine betaine (GB) was more effective than DMSP in affecting ectoine levels, principally in strain ML-D. Strain ML-D accumulated GB to 50 or 67% of its organic solute pool at 2.5 M NaCl, at an external level of 0.1 or 1 mM GB, respectively. Strain ML-D also accumulated arsenobetaine. The methylated zwitterionic compounds, probably metabolic products of phytoplankton (DMSP and GB) or brine shrimps (arsenobetaine) in Mono Lake, may function as osmolytes for indigenous bacteria when present at high concentrations or under conditions of nitrogen limitation or salt stress.

  12. Analysis of fae and fhcD genes in Mono Lake, California.

    PubMed

    Nercessian, Olivier; Kalyuzhnaya, Marina G; Joye, Samantha B; Lidstrom, Mary E; Chistoserdova, Ludmila

    2005-12-01

    Genes for two enzymes of the tetrahydromethanopterin-linked C(1) transfer pathway (fae and fhcD) were detected in hypersaline, hyperalkaline Mono Lake (California), via PCR amplification and analysis. Low diversity for fae and fhcD was noted, in contrast to the diversity previously detected in a freshwater lake, Lake Washington (Washington).

  13. Organic geochemistry and brine composition in Great Salt, Mono, and Walker Lakes

    USGS Publications Warehouse

    Domagalski, J.L.; Orem, W.H.; Eugster, H.P.

    1989-01-01

    Samples of Recent sediments, representing up to 1000 years of accumulation, were collected from three closed basin lakes (Mono Lake, CA, Walker Lake, NV, and Great Salt Lake, UT) to assess the effects of brine composition on the accumulation of total organic carbon, the concentration of dissolved organic carbon, humic acid structure and diagenesis, and trace metal complexation. The Great Salt Lake water column is a stratified Na-Mg-Cl-SO4 brine with low alkalinity. Algal debris is entrained in the high density (1.132-1.190 g/cc) bottom brines, and in this region maximum organic matter decomposition occurs by anaerobic processes, with sulfate ion as the terminal electron acceptor. Organic matter, below 5 cm of the sediment-water interface, degrades at a very slow rate in spite of very high pore-fluid sulfate levels. The organic carbon concentration stabilizes at 1.1 wt%. Mono Lake is an alkaline (Na-CO3-Cl-SO4) system. The water column is stratified, but the bottom brines are of lower density relative to the Great Salt Lake, and sedimentation of algal debris is rapid. Depletion of pore-fluid sulfate, near l m of core, results in a much higher accumulation of organic carbon, approximately 6 wt%. Walker Lake is also an alkaline system. The water column is not stratified, and decomposition of organic matter occurs by aerobic processes at the sediment-water interface and by anaerobic processes below. Total organic carbon and dissolved organic carbon concentrations in Walker Lake sediments vary with location and depth due to changes in input and pore-fluid sulfate concentrations. Nuclear magnetic resonance studies (13C) of humic substances and dissolved organic carbon provide information on the source of the Recent sedimentary organic carbon (aquatic vs. terrestrial), its relative state of decomposition, and its chemical structure. The spectra suggest an algal origin with little terrestrial signature at all three lakes. This is indicated by the ratio of aliphatic to

  14. Organic geochemistry and brine composition in Great Salt, Mono, and Walker Lakes

    NASA Astrophysics Data System (ADS)

    Domagalski, Joseph L.; Orem, William H.; Eugster, Hans P.

    1989-11-01

    Samples of Recent sediments, representing up to 1000 years of accumulation, were collected from three closed basin lakes (Mono Lake, CA, Walker Lake, NV, and Great Salt Lake, UT) to assess the effects of brine composition on the accumulation of total organic carbon, the concentration of dissolved organic carbon, humic acid structure and diagenesis, and trace metal complexation. The Great Salt Lake water column is a stratified Na-Mg-Cl-SO 4 brine with low alkalinity. Algal debris is entrained in the high density (1.132-1.190 g/cc) bottom brines, and in this region maximum organic matter decomposition occurs by anaerobic processes, with sulfate ion as the terminal electron acceptor. Organic matter, below 5 cm of the sediment-water interface, degrades at a very slow rate in spite of very high pore-fluid sulfate levels. The organic carbon concentration stabilizes at 1.1 wt%. Mono Lake is an alkaline (Na-CO 3-Cl-SO 4) system. The water column is stratified, but the bottom brines are of lower density relative to the Great Salt Lake, and sedimentation of algal debris is rapid. Depletion of pore-fluid sulfate, near l m of core, results in a much higher accumulation of organic carbon, approximately 6 wt%. Walker Lake is also an alkaline system. The water column is not stratified, and decomposition of organic matter occurs by aerobic processes at the sediment-water interface and by anaerobic processes below. Total organic carbon and dissolved organic carbon concentrations in Walker Lake sediments vary with location and depth due to changes in input and pore-fluid sulfate concentrations. Nuclear magnetic resonance studies ( 13C) of humic substances and dissolved organic carbon provide information on the source of the Recent sedimentary organic carbon (aquatic vs. terrestrial), its relative state of decomposition, and its chemical structure. The spectra suggest an algal origin with little terrestrial signature at all three lakes. This is indicated by the ratio of aliphatic to

  15. Sources and flux of natural gases from Mono Lake, California

    USGS Publications Warehouse

    Oremland, R.S.; Miller, L.G.; Whiticar, Michael J.

    1987-01-01

    The ability to identify a formation mechanism for natural gas in a particular environment requires consideration of several geochemical factors when there are multiple sources present. Four primary sources of methane have been identified in Mono Lake. Two of these sources were associated with numerous natural gas seeps which occur at various locations in the lake and extend beyond its present boundary; the two other gas sources result from current microbiological processes. In the natural gas seeps, we observed flow rates as high as 160 moles CH4 day-1, and estimate total lakewide annual seep flux to be 2.1 ?? 106 moles CH4. Geochemical parameters (??13CH4,??DCH4,CH4/[C2H6+ C3H8]) and ??14CH4measurements revealed that most of the seeps originate from a paleo-biogenic (??13CH4 = about -70%.). natural gas deposit of Pleistocene age which underlies the current and former lakebed. Gas seeps in the vicinity of hot springs had, in combination with the biogenic gas, a prominent thermogenic gas component resulting from hydrothermal alteration of buried organic matter. Current microbiological processes responsible for sources of natural gas in the lake included pelagic meth- anogenesis and decomposition of terrestrial grasses in the littoral zone. Methanogenesis in the pelagic sediments resulted in methane saturation (2-3 mM at 50 cm; ??13CH4 = about -85%.). Interstitial sulfate decreased from 133 mM at the surface to 35 mM by 110 cm depth, indicating that sulfate-reduction and methanogenesis operated concurrently. Methane diffused out of the sediments resulting in concentrations of about 50 ??M in the anoxic bottom waters. Methane oxidation in the oxic/anoxic boundry lowered the concentration by >98%, but values in surface waters (0.1-1.3??M) were supersaturated with respect to the atmosphere. The ??13CH4 (range = -21.8 to -71.8%.) of this unoxidized residual methane was enriched in 13C relative to methane in the bottom water and sediments. Average outward flux of this

  16. Anaerobic Halo-Alkaliphilic Baterial Community of Athalassic, Hypersaline Mono Lake in California

    NASA Technical Reports Server (NTRS)

    Pikuta, Elena V.; Hoover, Richard B.; Marsic, Damien; Ng, Joseph D.; Six, N. Frank (Technical Monitor)

    2002-01-01

    The microorganisms of soda Mono Lake and other similar athalassic hypersaline alkaline soda lakes are of significance to Astrobiology. The microorganisms of these regimes represent the best known terrestrial analogs for microbial life that might have inhabited the hypersaline alkaline lakes and evaporites confined within closed volcanic basins and impact craters during the late Noachian and early Hesperian epochs (3.6 - 4.2 Gya) of ancient Mars. We have investigated the anaerobic microbiota of soda Mono Lake in northern California. In this paper we discuss the astrobiological significance of these ecosystems and describe several interesting features of two novel new species of anaerobic halo-alkaliphilic bacteria (Spirochaeta americana, sp. nov. and Desulfonatronum paiuteum, sp. nov) that we have isolated from Mono Lake.

  17. Ikaite precipitation by mixing of shoreline springs and lake water, Mono Lake, California, USA

    USGS Publications Warehouse

    Bischoff, J.L.; Stine, S.; Rosenbauer, R.J.; Fitzpatrick, J.A.; Stafford, Thomas W.

    1993-01-01

    Metastable ikaite (CaCO3??6H2O) forms abundantly during winter months along the south shoreline of Mono Lake where shoreline springs mix with lake water. Ikaite precipitates because of its decreased solubility at low temperature and because of orthophosphate-ion inhibition of calcite and aragonite. During the spring some of the ikaite is transformed to anhydrous CaCO3 and is incorporated into tufa, but most is dispersed by wave action into the lake where it reacts to form gaylussite (Na2Ca(CO3)2?? 5H2O). Spring waters have low pH values, are dominantly Ca-Na-HCO3, have low radiocarbon activities, and are mixtures of deep-seated geothermal and cold groundwaters. Chemical modeling reveals that precipitation of CaCO3 can occur over a broad range of mixtures of spring and lake water with a maximum production occurring at 96% spring water and 4% lake water. Under these conditions all the Ca and a significant fraction of the CO3 of the precipitate is spring supplied. A radiocarbon age of 19,580 years obtained on a natural ikaite sample supports this conclusion. With the springs supplying a large and probably variable portion of the carbonate, and with apparent 14C age of the carbonate varying from spring to spring, tufa of similar actual antiquity may yield significantly different 14C dates, making tufa at this location unsuitable for absolute age dating by the radiocarbon method. ?? 1993.

  18. Dissimilatory arsenate and sulfate reduction in sediments of two hypersaline, arsenic-rich soda lakes: Mono and Searles Lakes, California.

    PubMed

    Kulp, T R; Hoeft, S E; Miller, L G; Saltikov, C; Murphy, J N; Han, S; Lanoil, B; Oremland, R S

    2006-10-01

    A radioisotope method was devised to study bacterial respiratory reduction of arsenate in sediments. The following two arsenic-rich soda lakes in California were chosen for comparison on the basis of their different salinities: Mono Lake (approximately 90 g/liter) and Searles Lake (approximately 340 g/liter). Profiles of arsenate reduction and sulfate reduction were constructed for both lakes. Reduction of [73As]arsenate occurred at all depth intervals in the cores from Mono Lake (rate constant [k] = 0.103 to 0.04 h(-1)) and Searles Lake (k = 0.012 to 0.002 h(-1)), and the highest activities occurred in the top sections of each core. In contrast, [35S]sulfate reduction was measurable in Mono Lake (k = 7.6 x10(4) to 3.2 x 10(-6) h(-1)) but not in Searles Lake. Sediment DNA was extracted, PCR amplified, and separated by denaturing gradient gel electrophoresis (DGGE) to obtain phylogenetic markers (i.e., 16S rRNA genes) and a partial functional gene for dissimilatory arsenate reduction (arrA). The amplified arrA gene product showed a similar trend in both lakes; the signal was strongest in surface sediments and decreased to undetectable levels deeper in the sediments. More arrA gene signal was observed in Mono Lake and was detectable at a greater depth, despite the higher arsenate reduction activity observed in Searles Lake. A partial sequence (about 900 bp) was obtained for a clone (SLAS-3) that matched the dominant DGGE band found in deeper parts of the Searles Lake sample (below 3 cm), and this clone was found to be closely related to SLAS-1, a novel extremophilic arsenate respirer previously cultivated from Searles Lake.

  19. Dissimilatory arsenate and sulfate reduction in sediments of two hypersaline, arsenic-rich soda lakes: Mono and Searles Lakes, California

    USGS Publications Warehouse

    Kulp, T.R.; Hoeft, S.E.; Miller, L.G.; Saltikov, C.; Murphy, J.N.; Han, S.; Lanoil, B.; Oremland, R.S.

    2006-01-01

    A radioisotope method was devised to study bacterial respiratory reduction of arsenate in sediments. The following two arsenic-rich soda lakes in California were chosen for comparison on the basis of their different salinities: Mono Lake (???90 g/liter) and Searles Lake (???340 g/liter). Profiles of arsenate reduction and sulfate reduction were constructed for both lakes. Reduction of [73As] arsenate occurred at all depth intervals in the cores from Mono Lake (rate constant [k] = 0.103 to 0.04 h-1) and Searles Lake (k = 0.012 to 0.002 h-1), and the highest activities occurred in the top sections of each core. In contrast, [35S] sulfate reduction was measurable in Mono Lake (k = 7.6 ?? 104 to 3.2 ?? 10-6 h-1) but not in Searles Lake. Sediment DNA was extracted, PCR amplified, and separated by denaturing gradient gel electrophoresis (DGGE) to obtain phylogenetic markers (i.e., 16S rRNA genes) and a partial functional gene for dissimilatory arsenate reduction (arrA). The amplified arrA gene product showed a similar trend in both lakes; the signal was strongest in surface sediments and decreased to undetectable levels deeper in the sediments. More arrA gene signal was observed in Mono Lake and was detectable at a greater depth, despite the higher arsenate reduction activity observed in Searles Lake. A partial sequence (about 900 bp) was obtained for a clone (SLAS-3) that matched the dominant DGGE band found in deeper parts of the Searles Lake sample (below 3 cm), and this clone was found to be closely related to SLAS-1, a novel extremophilic arsenate respirer previously cultivated from Searles Lake. Copyright ?? 2006, American Society for Microbiology. All Rights Reserved.

  20. Organic geochemistry and brine composition in Great Salt, Mono, and Walker Lakes

    SciTech Connect

    Domagalski, J.L.; Orem, W.H.; Eugster, H.P.

    1989-01-01

    Samples of recent sediments, representing up to 1,000 years of accumulation, were collected from three closed basin lakes to assess the effects of brine composition on the accumulation of effects of brine composition on the accumulation of total organic carbon, the concentration of dissolved organic carbon, humic acid structure and diagenesis, and trace metal complexation. The Great Salt Lake water column is a stratified Na-Mg-Cl-SO{sub 4} brine with low alkalinity. Algal debris is entrained in the high density (1.132-1.190 g/ml) bottom brines, and in this region maximum organic matter decomposition occurs by anaerobic processes, with sulfate ion as the terminal electron acceptor. Organic matter, below 5 cm of the sediment-water interface, degrades at a very slow rate in spite of very high pore-fluid sulfate levels. Mono Lake is an alkaline (Na-CO{sub 3}-Cl-SO{sub 4}) system. The water column is stratified, but the bottom brines are of lower density relative to the Great Salt Lake, and sedimentation of algal debris is rapid. Walker Lake is also an alkaline system. The water column is not stratified, and decomposition of organic matter occurs by aerobic processes at the sediment-water interface and by anaerobic processes below. Total organic carbon and dissolved organic carbon concentrations in Walker Lake sediments vary with location and depth due to changes in input and pore-fluid sulfate concentrations. Nuclear magnetic resonance studies of humic substances and dissolved organic carbon provide information on the source of the recent sedimentary organic carbon, its relative state of decomposition, and its chemical structure. 44 refs., 10 figs., 6 tabs.

  1. Organic osmolytes in aerobic bacteria from Mono Lake, an alkaline, moderately hypersaline environment

    SciTech Connect

    Ciulla, R.A.; Roberts, M.F.; Diaz, M.R.; Taylor, B.F.

    1997-01-01

    The identity and concentrations of intracellular organic solutes were determined by nuclear magnetic resonance spectroscopy for two strains of aerobic, gram-negative bacteria isolated from Mono Lake, California, an alkaline, moderately hypersaline lake. Ectoine (1,4,5,6-tetrahydro-2-methyl-4-pyrimidinecarboxylic acid) was the major endogenous solute in both organisms. Concentrations of ectoine varied with external NaCl levels in strain ML-D but not in strain ML-G, where the level was high but invariant from 1.5 to 3.0 M NaCl. Hydroxyectoine also occurred in strain ML-D, especially at elevated NaCl concentrations (2.5 and 3.0 M), but at levels lower than those of ectoine. Exogenous organic solutes that might occur in Mono Lake were examined for their effects on the de novo synthesis of ectoine. Dimethylsulfoniopropionate (DMSP) (0.1 or 1 mM) did not significantly lower ectoine levels in either isolate, and only strain ML-G showed any capacity for DMSP accumulation. With nitrogen limitation, however, DMSP (0.1 mM) substituted for ectoine in strain ML-G showed any capacity for DMSP accumulation. With nitrogen limitation, however, DMSP (0.1 mM) substituted for ectoine in strain ML-G and became the main organic solute. Glycine betaine (GB) was more effective than DMSP in affecting ectoine levels, principally in strain ML-D. Strain ML-D accumulated GB to 50 or 67% of its organic solute pool at 2.5 M NaCl, at an external level of 0.1 or 1 mM GB, respectively. Strain ML-D also accumulated arsenobetaine. The methylated zwitterionic compounds, probably metabolic products of phytoplankton (DMSP and GB) or brine shrimps (arsenobetaine) in Mono Lake, may function as osmolytes for indigenous bacteria when present at high concentrations or under conditions of nitrogen limitation or salt stress. 33 refs., 5 figs., 2 tabs.

  2. Morphological characterization of viruses in the stratified water column of alkaline, hypersaline Mono Lake.

    PubMed

    Brum, Jennifer R; Steward, Grieg F

    2010-10-01

    Concentrations of viruses and prokaryotes in the alkaline, moderately hypersaline, seasonally stratified Mono Lake are among the highest reported for a natural aquatic environment. We used electron microscopy to test whether viral morphological characteristics differed among the epilimnion, metalimnion, and the anoxic hypolimnion of the lake and to determine how the properties of viruses in Mono Lake compare to other aquatic environments. Viral capsid size distributions were more similar in the metalimnion and hypolimnion of Mono Lake, while viral tail lengths were more similar in the epilimnion and metalimnion. The percentage of tailed viruses decreased with depth and the relative percentages of tailed phage families changed with depth. The presence of large (>125 nm capsid), untailed viruses in the metalimnion and hypolimnion suggests that eukaryotic viruses are produced in these suboxic and anoxic, hypersaline environments. Capsid diameters of viruses were larger on average in Mono Lake compared to other aquatic environments, and no lemon-shaped or filamentous viruses were found, in contrast to other high-salinity or high-altitude lakes and seas. Our data suggest that the physically and chemically distinct layers of Mono Lake harbor different viral assemblages, and that these assemblages are distinct from other aquatic environments that have been studied. Furthermore, we found that filtration of a sample through a 0.22-µm pore-size filter significantly altered the distribution of viral capsid diameters and tail lengths, resulting in a relative depletion of viruses having larger capsids and longer tails. This observation highlights the potential for bias in molecular surveys of viral diversity, which typically rely on filtration through 0.2- or 0.22-µm pore-size membrane filters to remove bacteria during sample preparation.

  3. Dust Generation Resulting from Desiccation of Playa Systems: Studies on Mono and Owens Lakes, California

    NASA Astrophysics Data System (ADS)

    Gill, Thomas Edward

    1995-01-01

    Playas, evaporites, and aeolian sediments frequently are linked components within the Earth system. Anthropogenic water diversions from terminal lakes form playas that release fugitive dust. These actions, documented worldwide, simulate aeolian processes activated during palaeoclimatic pluvial/interpluvial transitions, and have significant environmental impacts. Pluvial lakes Russell and Owens in North America's Great Basin preceded historic Mono and Owens Lakes, now desiccated by water diversions into dust-generating, evaporite -encrusted playas. Geochemical and hydrologic cycles acting on the Owens (Dry) Lake playa form three distinct crust types each year. Although initial dust production results from deflation of surface efflorescences after the playa dries, most aerosols are created by saltation abrasion of salt/silt/clay crusts at crust/ sand sheet contacts. The warm-season, clastic "cemented" crust is slowest to degrade into dust. If the playa surface is stabilized by an unbroken, non-efflorescent crust, dust formation is discouraged. When Mono Lake's surFace elevation does not exceed 1951 meters (6400 feet), similar processes will also generate dust from its saline lower playa. Six factors--related to wind, topography, groundwater, and sediments--control dust formation at both playas. These factors were combined into a statistical model relating suspended dust concentrations to playa/lake morphometry. The model shows the extent and severity of Mono Lake dust storms expands significantly below the surface level 6376 feet (1943.5 meters). X-ray diffraction analysis of Mono Basin soils, playa sediments, and aerosols demonstrates geochemical cycling of materials through land, air and water during Mono Lake's 1982 low stand. Soils and clastic playa sediments contain silicate minerals and tephra. Saline groundwater deposited calcite, halite, thenardite, gaylussite, burkeite and glauberite onto the lower playa. Aerosols contained silicate minerals (especially

  4. 40 CFR 721.10505 - Phosphoric acid, mixed mono- and diesters with 2-ethyl-1-hexanol and polyethylene glycol mono-C12...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... diesters with 2-ethyl-1-hexanol and polyethylene glycol mono-C12-16-alkyl ethers. 721.10505 Section 721... Phosphoric acid, mixed mono- and diesters with 2-ethyl-1-hexanol and polyethylene glycol mono-C12-16-alkyl... identified as phosphoric acid, mixed mono- and diesters with 2-ethyl-1-hexanol and polyethylene glycol...

  5. 40 CFR 721.10505 - Phosphoric acid, mixed mono- and diesters with 2-ethyl-1-hexanol and polyethylene glycol mono-C12...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... diesters with 2-ethyl-1-hexanol and polyethylene glycol mono-C12-16-alkyl ethers. 721.10505 Section 721... Phosphoric acid, mixed mono- and diesters with 2-ethyl-1-hexanol and polyethylene glycol mono-C12-16-alkyl... identified as phosphoric acid, mixed mono- and diesters with 2-ethyl-1-hexanol and polyethylene glycol...

  6. Correlation of Late-Pleistocene Lake-Level Oscillations in Mono Lake, California, with North Atlantic Climate Events

    USGS Publications Warehouse

    Benson, L.V.; Lund, S.P.; Burdett, J.W.; Kashgarian, Michaele; Rose, T.P.; Smoot, J.P.; Schwartz, M.

    1998-01-01

    Oxygen-18 (18O) values of sediment from the Wilson Creek Formation, Mono Basin, California, indicate three scales of temporal variation (Dansgaard-Oeschger, Heinrich, and Milankovitch) in the hydrologic balance of Mono Lake between 35,400 and 12,900 14C yr B.P. During this interval, Mono Lake experienced four lowstands each lasting from 1000 to 2000 yr. The youngest low-stand, which occurred between 15,500 and 14,000 14C yr B.P., was nearly synchronous with a desiccation of Owens Lake, California. Paleomagnetic secular variation (PSV) data indicate that three of four persistent lowstands occurred at the same times as Heinrich events H1, H2, and H4. 18O data indicate the two highest lake levels occurred ???18,000 and ???13,100 14C yr B.P., corresponding to passages of the mean position of the polar jet stream over the Mono Basin. Extremely low values of total inorganic carbon between 26,000 and 14,000 14C yr B.P. indicate glacial activity, corresponding to a time when summer insolation was much reduced. ?? 1998 University of Washington.

  7. 40 CFR 721.8340 - Mono esters from 2- propenoic acid (generic).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Mono esters from 2- propenoic acid... Specific Chemical Substances § 721.8340 Mono esters from 2- propenoic acid (generic). (a) Chemical... as mono esters from 2-propenoic acid (PMN P-01-85) is subject to reporting under this section for...

  8. 40 CFR 721.8340 - Mono esters from 2- propenoic acid (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Mono esters from 2- propenoic acid... Specific Chemical Substances § 721.8340 Mono esters from 2- propenoic acid (generic). (a) Chemical... as mono esters from 2-propenoic acid (PMN P-01-85) is subject to reporting under this section for...

  9. 21 CFR 184.1101 - Diacetyl tartaric acid esters of mono- and diglycerides.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Diacetyl tartaric acid esters of mono- and... acid esters of mono- and diglycerides. (a) Diacetyl tartaric acid esters of mono- and diglycerides, also know as DATEM, are composed of mixed esters of glycerin in which one or more of the...

  10. 21 CFR 184.1101 - Diacetyl tartaric acid esters of mono- and diglycerides.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Diacetyl tartaric acid esters of mono- and... acid esters of mono- and diglycerides. (a) Diacetyl tartaric acid esters of mono- and diglycerides, also know as DATEM, are composed of mixed esters of glycerin in which one or more of the...

  11. 21 CFR 184.1101 - Diacetyl tartaric acid esters of mono- and diglycerides.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Diacetyl tartaric acid esters of mono- and... acid esters of mono- and diglycerides. (a) Diacetyl tartaric acid esters of mono- and diglycerides, also know as DATEM, are composed of mixed esters of glycerin in which one or more of the...

  12. 40 CFR 721.8340 - Mono esters from 2- propenoic acid (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Mono esters from 2- propenoic acid... Specific Chemical Substances § 721.8340 Mono esters from 2- propenoic acid (generic). (a) Chemical... as mono esters from 2-propenoic acid (PMN P-01-85) is subject to reporting under this section for...

  13. 21 CFR 184.1101 - Diacetyl tartaric acid esters of mono- and diglycerides.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Diacetyl tartaric acid esters of mono- and... acid esters of mono- and diglycerides. (a) Diacetyl tartaric acid esters of mono- and diglycerides, also know as DATEM, are composed of mixed esters of glycerin in which one or more of the...

  14. 40 CFR 721.8340 - Mono esters from 2- propenoic acid (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Mono esters from 2- propenoic acid... Specific Chemical Substances § 721.8340 Mono esters from 2- propenoic acid (generic). (a) Chemical... as mono esters from 2-propenoic acid (PMN P-01-85) is subject to reporting under this section for...

  15. 21 CFR 184.1101 - Diacetyl tartaric acid esters of mono- and diglycerides.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Diacetyl tartaric acid esters of mono- and... Specific Substances Affirmed as GRAS § 184.1101 Diacetyl tartaric acid esters of mono- and diglycerides. (a) Diacetyl tartaric acid esters of mono- and diglycerides, also know as DATEM, are composed of mixed...

  16. 40 CFR 721.8340 - Mono esters from 2- propenoic acid (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Mono esters from 2- propenoic acid... Specific Chemical Substances § 721.8340 Mono esters from 2- propenoic acid (generic). (a) Chemical... as mono esters from 2-propenoic acid (PMN P-01-85) is subject to reporting under this section for...

  17. Temporal correlation of U. S. Great Basin lake sediments below the Mono Lake Excursion using paleomagnetic secular variation

    NASA Astrophysics Data System (ADS)

    Liddicoat, J. C.; Coe, R. S.; Negrini, R. M.; Knott, J. R.; Lund, S.; Benson, L. V.

    2015-12-01

    Beginning nearly 50 years ago with a paleomagnetic study of exposed lacustrine sediments in the Mono Basin, CA (Denham and Cox, 1971), there have been subsequent studies to document paleomagnetic secular variation (PSV) in the basin and to establish a chronology for that record (Vazquez and Lidzbarski, 2012). We report a paleomagnetic secular variation (PSV) investigation of lacustrine sediments in the Mono Basin, CA, that extends the base of the PSV record of Lund et al. (1988) by about 20 percent. We did our investigation at two localities separated by about 4 km on the southeastern and eastern sides of Mono Lake: South Shore Cliffs (SSC) and Warm Springs (WS). The sampled interval at SSC is from 0.1 m above to 2.2 m below Wilson Creek Ash 19 in the tephrostratigraphy of Lajoie (1968), ending in loose sand. At WS, we sampled from Ash 17 to 1.0 m below Ash 19, a total of 2 m. At SSC using back-to-back horizons 2-cm thick containing one to three samples each that were a.f. or thermally demagnetized, we found rapidly fluctuating PSV in the interval from ~ 0.3 to 1.0 m below Ash 19. The fluctuating PSV contains a change in declination of ~ 80˚ from 308˚ (n = 3, α-95: 6.1˚) to 29˚ (n = 3, α-95: 11.5˚) within a single hand sample that spans 14 cm. Inclination during that change in declination gradually rose from 56˚ to 63˚ and increased to 70˚ before reducing to a minimum of 29.9˚. The path of the Virtual Geomagnetic Poles when the declination is most westerly forms a narrow loop that reaches 49.7˚ N latitude near 170˚ E longitude. At WS the westerly swing in declination is absent, but the easterly declination and relatively steep inclination described above are recorded. A study of the relative paleomagnetic intensity (RPI) shows that the maximum RPI is ~1.5 m below Ash 19 and decreases to a minimum ~6 cm above the ash. Distinct PSV and RPI features below the Mono Lake excursion correlate well between records from the periphery of Mono Lake and those from

  18. Systematic Behavior of the Non-dipole Magnetic Field during the 32 ka Mono Lake Excursion

    NASA Astrophysics Data System (ADS)

    Negrini, R. M.; McCuan, D.; Cassata, W. S.; Channell, J. E.; Verosub, K. L.; Liddicoat, J. C.; Knott, J. R.; Coe, R. S.; Benson, L. V.; Sarna-Wojcicki, A.; Lund, S.; Horton, R.; Lopez, J.

    2012-12-01

    Paleomagnetic excursions are enigmatic phenomena that reveal geodynamo behavior in its transitional state and provide important refinements in age control for the late Pleistocene, a critical time period for the study of paleoclimate and human evolution. We report here on two widely separated, unusually detailed records of the Mono Lake excursion (MLE) from sedimentary sequences dated at 32 ka. One of the records is from Summer Lake, Oregon. The vector components of this new record faithfully reproduce the principle features of the MLE as recorded at the type localities around Mono Lake, CA, though with greater detail and higher amplitude. Radiocarbon dates on bulk organics in the Summer Lake record confirm the 32 ka age of the MLE. The other record is from the marine Irminger Basin off of eastern Greenland and is based on the measurement of discrete samples rather than u-channels. The associated VGP paths of the two records strongly suggest systematic field behavior that includes three loci of nondipole flux whose relative dominance oscillates through time. The staggered sequence followed by the two paths through each flux locus further suggests that both the demise and return of the main field floods zonally during the excursion. The composite path is also compatible with the VGPs of a 32 ka set of lavas from New Zealand and, notably, it does not include VGPs associated with the 40 ka Laschamp excursion. This confirms that these two excursions are distinct events and, more specifically, shows that it is the 32 ka Mono Lake excursion that is recorded in the sediments surrounding Mono Lake rather than the ~40 ka Laschamp excursion.

  19. Lake Level Changes in the Mono Basin During the Last Deglacial Period

    NASA Astrophysics Data System (ADS)

    Wang, X.; Ali, G.; Hemming, S. R.; Zimmerman, S. R. H.; Stine, S. W.; Hemming, G.

    2014-12-01

    Mono Basin, located in the southwestern corner of the US Great Basin, has long been known to have experienced large lake level changes, particularly during the last deglaciation. But until recently it was not possible to establish a reliable lake level time series. We discovered many visually clean, white, shiny, dense calcite samples in the basin, associated with tufa deposits from high terraces. Their low thorium, but high uranium contents allow precise and reproducible U/Th age determinations. A highly resolved history of a minimum lake level through the last deglaciation can therefore be inferred based on sample locations and their ages. We found that the lake level reached ~2030 m asl at ~20.4 ka, evidenced by calcite coatings on a tufa mound at the upper Wilson Creek. The lake then rose to ~2075 m by ~19.1 ka, shown by calcite cements on conglomerates from the Hansen Cut terrace. The lake climbed to at least ~2140 m at ~15.9 ka, indicated by beach calcites from the east Sierra slope. Such timing of the highest lake stand, occurring within Heinrich Stadial 1, is reinforced by U/Th dates on calcite coatings from widespread locations in the basin, including the Bodie Hills and Cowtrack Mountains. The lake then dropped rapidly to ~2075 m at ~14.5 ka. It stood near this height over the next ~300 years, evidenced by a few-centimeter thick, laminated calcite rims on the Goat Ranch tufa mounds. It subsequently plunged to ~2007 m at ~13.8 ka, indicated by calcite coatings from cemetery road tufa mounds. The lake level came back to ~2030 m at ~12.9 ka, as seen in upper Wilson Creek tufa mounds. The lake level had a few fluctuations within the Younger Dryas, and even shot up to ~2075 m at ~12.0 ka. It then fell to levels in accord with Holocene climatic conditions. Relative to the present lake level of ~1950 m, Mono Lake broadly stood high during Heinrich Stadial 1 and Younger Dryas, when the climate was extremely cold over the North Atlantic, and the Asian monsoon was

  20. First survey of fungi in hypersaline soil and water of Mono Lake area (California).

    PubMed

    Steiman, Régine; Ford, Larry; Ducros, Véronique; Lafond, Jean-Luc; Guiraud, Pascale

    2004-01-01

    Mono Lake is a closed lake located in central California, east of the Sierra Nevada mountains. It contains dissolved carbonates, sulfates and chlorides at high concentrations. Due to its high salinity, Mono Lake was sometimes compared to the Dead Sea. However, it appears that Mono Lake water and vicinity abound with life. In this work, the fungal flora living in this extreme ecosystem was studied for the first time. Soil, tufa, water and sediment samples were also analyzed for their mineral and salt composition. Results showed that water was particularly rich in sodium, potassium, phosphorus and boron. Soil and sediments contained very high levels of calcium and magnesium, but also barium, boron and strontium. Sodium, phosphorus and iron levels varied in a large extent from one to another sample. Neutral to very alkaline pH were recorded. Water samples were found sterile in the conditions chosen for fungi isolation, while sediment, soil and tufa samples led to the isolation of a total of 67 fungal species (from 23 samples), belonging to various taxonomic groups. From our results no clear effects of the chemical parameters of the samples were observed on fungal life apart from the pH. The methods chosen did not allow the isolation of extremely halotolerant species. We isolated in this work a series of ubiquitous species, suggesting that a selection of resistant and/or adaptable strains of some common species could have occurred. Depending on the medium and the temperature of isolation, it can be hypothesized that some species were present as dormant structures, while some others, isolated at pH 8 on a medium enriched in Na and Ca, could be in a growing form adapted to alkaline and saline conditions. This work contributes to a better knowledge of the mycobiota present in the Mono Lake's ecosystem.

  1. 40 CFR 747.115 - Mixed mono and diamides of an organic acid.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Mixed mono and diamides of an organic... Substances § 747.115 Mixed mono and diamides of an organic acid. This section identifies activities with... subject to this section: P-84-529, mixed mono and diamides of an organic acid. (b)...

  2. 40 CFR 747.115 - Mixed mono and diamides of an organic acid.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Mixed mono and diamides of an organic... Substances § 747.115 Mixed mono and diamides of an organic acid. This section identifies activities with... subject to this section: P-84-529, mixed mono and diamides of an organic acid. (b)...

  3. 40 CFR 747.115 - Mixed mono and diamides of an organic acid.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Mixed mono and diamides of an organic... Substances § 747.115 Mixed mono and diamides of an organic acid. This section identifies activities with... subject to this section: P-84-529, mixed mono and diamides of an organic acid. (b)...

  4. 40 CFR 747.115 - Mixed mono and diamides of an organic acid.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Mixed mono and diamides of an organic... Substances § 747.115 Mixed mono and diamides of an organic acid. This section identifies activities with... subject to this section: P-84-529, mixed mono and diamides of an organic acid. (b)...

  5. Mono Lake Excursion as a Chronologic Marker in the U.S. Great Basin

    NASA Astrophysics Data System (ADS)

    Liddicoat, J. C.; Coe, R. S.; Knott, J. R.

    2008-05-01

    Nevada, Utah, and California east of the Sierra Nevada are in the Great Basin physiographic province of western North America. During periods of the Pleistocene, Lake Bonneville and Lake Lahontan covered valleys in Utah and Nevada, respectively, and other lakes such as Lake Russell in east-central California did likewise (Feth, 1964). Now dry except for its remnant, Mono Lake, Lake Russell provides an opportunity to study behavior of Earth's past magnetic field in lacustrine sediments that are exposed in natural outcrops. The sediments record at least 30,000 years of paleomagnetic secular variation (Liddicoat, 1976; Zimmerman et al., 2006) and have been of particular interest since the discovery of the Mono Lake Excursion (MLE) by Denham and Cox (1971) because the field behavior can be documented at numerous sites around Mono Lake (Liddicoat and Coe, 1979, Liddicoat, 1992; Coe and Liddicoat, 1994) and on Paoha Island in the lake. Moreover, there have been recent attempts to date the excursion (Kent et al., 2002, Benson et al., 2003) more accurately and use the age and relative field intensity in paleoclimate research (Zimmerman et al., 2006). It has been proposed that the excursion in the Mono Basin might be older than originally believed (Denham and Cox, 1971; Liddicoat and Coe, 1979) and instead be the Laschamp Excursion (LE), ~ 40,000 yrs B.P. (Guillou et al., 2004), on the basis of 14C and 40Ar/39Ar dates (Kent et al., 2002) and the relative paleointensity record (Zimmerman et al., 2006) for the excursion in the Mono Basin. On the contrary, we favor a younger age for the excursion, ~ 32,000 yrs B.P., using the relative paleointensity at the Mono and Lahontan basins and 14C dates from the Lahontan Basin (Benson et al., 2003). The age of ~ 32,000 yrs B.P. is in accord with the age (32,000-34,000 yrs B.P.) reported by Channell (2006) for the MLE at Ocean Drilling Program (ODP) Site 919 in the Irminger Basin in the North Atlantic Ocean, which contains as well an

  6. Effect of benthic boundary layer transport on the productivity of Mono Lake, California.

    PubMed

    Bruce, Louise C; Jellison, Robert; Imberger, Jörg; Melack, John M

    2008-08-19

    The significance of the transport of nutrient-rich hypolimnetic water via the benthic boundary layer (BBL) to the productivity of Mono Lake was studied using a coupled hydrodynamic and ecological model validated against field data. The coupled model enabled us to differentiate between the role of biotic components and hydrodynamic forcing on the internal recycling of nutrients necessary to sustain primary productivity. A 4-year period (1991-1994) was simulated in which recycled nutrients from zooplankton excretion and bacterially-mediated mineralization exceeded sediment fluxes as the dominant source for primary productivity. Model outputs indicated that BBL transport was responsible for a 53% increase in the flux of hypolimnetic ammonium to the photic zone during stratification with an increase in primary production of 6% and secondary production of 5%. Although the estimated impact of BBL transport on the productivity of Mono Lake was not large, significant nutrient fluxes were simulated during periods when BBL transport was most active.

  7. Effect of benthic boundary layer transport on the productivity of Mono Lake, California

    PubMed Central

    Bruce, Louise C; Jellison, Robert; Imberger, Jörg; Melack, John M

    2008-01-01

    The significance of the transport of nutrient-rich hypolimnetic water via the benthic boundary layer (BBL) to the productivity of Mono Lake was studied using a coupled hydrodynamic and ecological model validated against field data. The coupled model enabled us to differentiate between the role of biotic components and hydrodynamic forcing on the internal recycling of nutrients necessary to sustain primary productivity. A 4-year period (1991–1994) was simulated in which recycled nutrients from zooplankton excretion and bacterially-mediated mineralization exceeded sediment fluxes as the dominant source for primary productivity. Model outputs indicated that BBL transport was responsible for a 53% increase in the flux of hypolimnetic ammonium to the photic zone during stratification with an increase in primary production of 6% and secondary production of 5%. Although the estimated impact of BBL transport on the productivity of Mono Lake was not large, significant nutrient fluxes were simulated during periods when BBL transport was most active. PMID:18710583

  8. Depth distribution of microbial diversity in Mono Lake, a meromictic soda lake in California.

    PubMed

    Humayoun, Shaheen B; Bano, Nasreen; Hollibaugh, James T

    2003-02-01

    We analyzed the variation with depth in the composition of members of the domain Bacteria in samples from alkaline, hypersaline, and currently meromictic Mono Lake in California. DNA samples were collected from the mixolimnion (2 m), the base of the oxycline (17.5 m), the upper chemocline (23 m), and the monimolimnion (35 m). Composition was assessed by sequencing randomly selected cloned fragments of 16S rRNA genes retrieved from the DNA samples. Most of the 212 sequences retrieved from the samples fell into five major lineages of the domain Bacteria: alpha- and gamma-Proteobacteria (6 and 10%, respectively), Cytophaga-Flexibacter-Bacteroides (19%), high-G+C-content gram-positive organisms (Actinobacteria; 25%), and low-G+C-content gram-positive organisms (Bacillus and Clostridium; 19%). Twelve percent were identified as chloroplasts. The remaining 9% represented beta- and delta-Proteobacteria, Verrucomicrobiales, and candidate divisions. Mixolimnion and oxycline samples had low microbial diversity, with only 9 and 12 distinct phylotypes, respectively, whereas chemocline and monimolimnion samples were more diverse, containing 27 and 25 phylotypes, respectively. The compositions of microbial assemblages from the mixolimnion and oxycline were not significantly different from each other (P = 0.314 and 0.877), but they were significantly different from those of chemocline and monimolimnion assemblages (P < 0.001), and the compositions of chemocline and monimolimnion assemblages were not significantly different from each other (P = 0.006 and 0.124). The populations of sequences retrieved from the mixolimnion and oxycline samples were dominated by sequences related to high-G+C-content gram-positive bacteria (49 and 63%, respectively) distributed in only three distinct phylotypes, while the population of sequences retrieved from the monimolimnion sample was dominated (52%) by sequences related to low-G+C-content gram-positive bacteria distributed in 12 distinct

  9. Calcite-impregnated defluidization structures in littoral sands of Mono Lake, California

    USGS Publications Warehouse

    Cloud, P.; Lajoie, K.R.

    1980-01-01

    Associated locally with well-known tufa mounds and towers of Mono Lake, California, are subvertical, concretionary sand structures through which fresh calcium-containing artesian waters moved up to sites of calcium carbonate precipitation beneath and adjacent to the lake. The structures include closely spaced calcite-impregnated columns, tubes, and other configurations with subcylindrical to bizarre cross sections and predominantly vertical orientation in coarse, barely coherent pumice sands along the south shore of the lake. Many structures terminate upward in extensive calcareous layers of caliche and tufa. Locally they enter the bases of tufa mounds and towers. A common form superficially resembles root casts and animal burrows except that branching is mostly up instead of down. Similar defluidization structures in ancient sedimentary rocks have been mistakenly interpreted as fossil burrows.

  10. High Resolution Seismic Imaging of the Trench Canyon Fault Zone, Mono Lake, Northeastern California

    NASA Astrophysics Data System (ADS)

    Novick, M. W.; Jayko, A. S.; Roeske, S.; McClain, J. S.; Hart, P. E.; Boyle, M.

    2009-12-01

    High resolution seismic imaging of Mono Lake, located in northeastern California, has revealed an approximately northwest striking fault in the area to the west of aerially exposed Negit Volcano. This fault, henceforth referred to as the Trench Canyon Fault (TCF), has also been mapped onshore along a correlating strike as far north as Cedar Hill Volcano, located to the northeast of the lake on the California/Nevada border. Onshore, the TCF was mapped for approximately 10 kilometers using air photos, DEM images, and standard geologic pace and compass mapping techniques. The TCF post- dates the last glacial maximum, evidenced by the cutting of wave cut benches along Cedar Hill Volcano. Relict, non-historic shorelines, left by the steady evaporation of Mono Lake beginning approximately 13k, are also repeatedly cut by the fault. Additional evidence of fault presence includes sag ponds, pressure ridges, tectonically fractured rocks, and normal fault scarps found along strike. Offshore, DEM images show a northeast striking structure to the northwest of Negit Volcano, which is co-linear with the onshore TCF. High resolution seismic imaging of the structure, using an applied acoustic/SIG mini-sparker system, reveals steeply dipping Holocene sediments, as well as volcanic deposits from active vents which have erupted in the last 1000 years, offset by the fault. Detailed structural analysis of the previously unstudied Trench Canyon Fault (TFC) and faults in the Cedar Hill region of northern California, along with seismic studies of sediments beneath Mono Lake not only allow for a better comprehension of this minor fault system, but provide greater understanding of the larger and more complex Walker Lane Shear Zone. Fault analyses, combined and correlated with those from CHV, give a better understanding of how slip is transferred into the complicated Mina defection to the east, from the dextral and normal faults along the Sierra Nevada Range front.

  11. 40 CFR 721.10437 - Sulfonic acid, linear xylene alkylate, mono, sodium salts (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Sulfonic acid, linear xylene alkylate... Significant New Uses for Specific Chemical Substances § 721.10437 Sulfonic acid, linear xylene alkylate, mono... chemical substances identified generically as sulfonic acid, linear xylene alkylate, mono, sodium...

  12. 40 CFR 721.10437 - Sulfonic acid, linear xylene alkylate, mono, sodium salts (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Sulfonic acid, linear xylene alkylate... Significant New Uses for Specific Chemical Substances § 721.10437 Sulfonic acid, linear xylene alkylate, mono... chemical substances identified generically as sulfonic acid, linear xylene alkylate, mono, sodium...

  13. Coupled arsenotrophy in a hot spring photosynthetic biofilm at Mono Lake, California.

    PubMed

    Hoeft, Shelley E; Kulp, Thomas R; Han, Sukkyun; Lanoil, Brian; Oremland, Ronald S

    2010-07-01

    Red-pigmented biofilms grow on rock and cobble surfaces present in anoxic hot springs located on Paoha Island in Mono Lake. The bacterial community was dominated ( approximately 85% of 16S rRNA gene clones) by sequences from the photosynthetic Ectothiorhodospira genus. Scraped biofilm materials incubated under anoxic conditions rapidly oxidized As(III) to As(V) in the light via anoxygenic photosynthesis but could also readily reduce As(V) to As(III) in the dark at comparable rates. Back-labeling experiments with (73)As(V) demonstrated that reduction to (73)As(III) also occurred in the light, thereby illustrating the cooccurrence of these two anaerobic processes as an example of closely coupled arsenotrophy. Oxic biofilms also oxidized As(III) to As(V). Biofilms incubated with [(14)C]acetate oxidized the radiolabel to (14)CO(2) in the light but not the dark, indicating a capacity for photoheterotrophy but not chemoheterotrophy. Anoxic, dark-incubated samples demonstrated As(V) reduction linked to additions of hydrogen or sulfide but not acetate. Chemoautotrophy linked to As(V) as measured by dark fixation of [(14)C]bicarbonate into cell material was stimulated by either H(2) or HS(-). Functional genes for the arsenate respiratory reductase (arrA) and arsenic resistance (arsB) were detected in sequenced amplicons of extracted DNA, with about half of the arrA sequences closely related ( approximately 98% translated amino acid identity) to those from the family Ectothiorhodospiraceae. Surprisingly, no authentic PCR products for arsenite oxidase (aoxB) were obtained, despite observing aerobic arsenite oxidation activity. Collectively, these results demonstrate close linkages of these arsenic redox processes occurring within these biofilms.

  14. Marinospirillum celere sp. nov., a novel haloalkaliphilic, helical bacterium isolated from Mono Lake.

    PubMed

    Namsaraev, Zorigto; Akimov, Vladimir; Tsapin, Alexandre; Barinova, Ekaterina; Nealson, Kenneth; Gorlenko, Vladimir

    2009-09-01

    Two strains of a Gram-negative, helical, haloalkaliphilic bacterium were isolated from Mono Lake (USA). Both strains were mesophilic and grew between 13 and 55 degrees C, with optimum growth at 35-45 degrees C. The optimum pH for growth was 9.5. Growth was observed at NaCl concentrations of 0.5-12% (w/v), with optimum growth at 2% NaCl. Both isolates were motile by means of bipolar tuft flagella, coccoid body-forming and strictly aerobic. It was concluded that they belong to the same species, based on DNA-DNA hybridization values (95% DNA relatedness). DNA G+C contents of the novel strains were 52.1 and 52.3 mol%. On the basis of 16S rRNA gene sequence similarity, both strains were shown to be related closely to the members of the genus Marinospirillum (family Oceanospirillaceae, class Gammaproteobacteria). Sequence similarity of strain v1c_Sn-redT to the type strains of Marinospirillum alkaliphilum, Marinospirillum minutulum, Marinospirillum megaterium and Marinospirillum insulare was 95.0, 92.7, 91.8 and 91.8%, respectively. Chemotaxonomic data [major ubiquinone, Q8; major fatty acids, C18:1(n-7) and C16:0] and physiological and biochemical tests supported the affiliation of the novel strains to the genus Marinospirillum as members of a novel species, for which the name Marinospirillum celere sp. nov. is proposed, with the type strain v1c_Sn-redT (=LMG 24610T=VKM 2416T).

  15. Abundance, distribution, and diversity of viruses in alkaline, hypersaline Mono Lake, California.

    PubMed

    Jiang, S; Steward, G; Jellison, R; Chu, W; Choi, S

    2004-01-01

    Mono Lake is a large (180 km2), alkaline (pH approximately 10), moderately hypersaline (70-85 g kg(-1)) lake lying at the western edge of the Great Basin. An episode of persistent chemical stratification (meromixis) was initiated in 1995 and has resulted in depletion of oxygen and accumulation of ammonia and sulfide beneath the chemocline. Although previous studies have documented high bacterial abundances and marked seasonal changes in phytoplankton abundance and community composition, there have been no previous reports on the occurrence of viruses in this unique lake. Based on the high concentrations and diversity of microbial life in this lake, we hypothesized that planktonic viruses are also abundant and diverse. To examine the abundance and distribution of viruses and bacteria, water samples were collected from four stations along 5 to 15 vertical depths at each station. Viral abundance ranged from 1 x 10(8) to 1 x 10(9) mL(-1), among the highest observed in any natural aquatic system examined so far. Increases (p < 0.1) in viral densities were observed in the anoxic bottom water at multiple stations. However, regression analysis indicated that viral abundance could not be predicted by any single environmental parameter. Pulsed field gel electrophoresis revealed a diverse viral community in Mono Lake with genome sizes ranging from approximately 14 to >400 kb with most of the DNA in the 30 to 60 kb size range. Cluster analysis grouped the anoxic bottom-water viral community into a unique cluster differentiating it from surface and mid-water viral communities. A hybridization study using an indigenous viral isolate as a probe revealed an episodic pattern of temporal phage distribution with strong niche stratification between oxic and anoxic waters.

  16. Mono Lake Excursion in Cored Sediment from the Eastern Tyrrhenian Sea

    NASA Astrophysics Data System (ADS)

    Liddicoat, Joseph; Iorio, Marina; Sagnotti, Leonardo; Incoronato, Alberto

    2013-04-01

    A search for the Laschamp and Mono Lake excursions in cored marine and lacustrine sediment younger than 50,000 years resulted in the discovery of both excursions in the Greenland Sea (73.3˚ N, 351.0˚ E, Nowaczyk and Antanow, 1997), in the North Atlantic Ocean (62.7˚ N, 222.5˚ E, Channell, 2006), in Pyramid Lake in the Lahontan Basin, NV, USA (40.1˚ N, 240.2˚ E, Benson et al., 2008), and in the Black Sea (43.2˚ N, 36.5˚ E, Nowaczyk et al., 2012). The inclination, declination, and relative field intensity during the Mono Lake Excursion (MLE) in the Black Sea sediment matches well the behaviour of the excursion in the Mono Basin, CA, in that a reduction in inclination during westerly declination is soon followed by steep positive inclination when declination is easterly, and relative field intensity increases after a low at the commencement of the excursion (Liddicoat and Coe, 1979). A large clockwise loop of Virtual Geomagnetic Poles (VGPs) at the Black Sea when followed from old to young patterns very well the VGP loop formed by the older portion of the MLE in the Mono Basin (Liddicoat and Coe, 1979). We also searched for the MLE in cored sediment from the eastern Tyrrhenian Sea (40.1˚ N, 14.7˚ E) where the age of the sediment is believed to be about 32,000 years when comparing the susceptibility in the core with the susceptibility in a nearby one that is dated by palaeomagnetic secular variation records, Carbon-14, and numerous tephra layers in the Tyrrhenian Sea sediment (Iorio et al., 2011). In the Tyrrhenian Sea core, called C1067, closely spaced samples demagnetized in an alternating field to100 mT record a shallowing of positive inclination to 48˚ that is followed by steep positive inclination of 82˚ when declination moves rapidly to the southeast. The old to young path of the VGPs in C1067 forms a narrow counter-clockwise loop that reaches 30.3˚ N, 30.8˚ E and that is centered at about 55˚ N, 15˚ E. Although descending to a latitude that is

  17. Methods and spatial extent of geophysical Investigations, Mono Lake, California, 2009 to 2011

    USGS Publications Warehouse

    Jayko, A.S.; Hart, P.E.; Childs, J. R.; Cormier, M.-H.; Ponce, D.A.; Athens, N.D.; McClain, J.S.

    2013-01-01

    This report summarizes the methods and spatial extent of geophysical surveys conducted on Mono Lake and Paoha Island by U.S. Geological Survey during 2009 and 2011. The surveys include acquisition of new high resolution seismic reflection data, shipborne high resolution magnetic data, and ground magnetic and gravity data on Paoha Island. Several trials to acquire swath bathymetry and side scan sonar were conducted, but were largely unsuccessful likely due to physical properties of the water column and (or) physical properites of the highly organic bottom sediment.

  18. High-resolution seismic imaging, Mono Lake fault zone, eastern Sierra region, Walker Lane, California

    NASA Astrophysics Data System (ADS)

    Jayko, A. S.; Childs, J. R.; Hart, P. E.; Bursik, M. I.; McClain, J. S.

    2012-12-01

    Multiple strands of the Mono Lake fault zone (MLfz), a segment of the Sierra Nevada frontal fault zone, have been imaged on several high-resolution seismic reflection profiles collected during 2009 and 2011 at Mono Lake. The profiles show coherent reflectors to about 30-40 ms depth below the lake bottom (~30 m thick section) in nearshore areas north of the Lee Vining delta. The MLfz is well imaged on 8 lines including 4 lines ~normal to the trend of the fault zone. The fault zone is ~ 0.75 km wide. Deep reflection horizons appear gently tilted and rotated into the fault zone with a prominent clastic wedge overlying the west-tilted horizons. Shallow reflectors above the clastic wedge are generally east-sloping, but noticeably less inclined above the fault zone. At least two ruptures offset Holocene deposits, with ~0.5-1.8 m dip-slip offset around 2.5 ka and ~3.6-6.13 m dip-slip offset around 4.7 to 6.25 ka. The ages of reflection horizons are estimated using published Holocene and late Pleistocene sedimentation rates, as well as correlation with a published nearby shallow core. The short term fault slip rate based on the timing of the most recent event and multiple events in the profile lines suggests fault slip rates of about 0.26 to 0.55 m/ka using ages based only on sedimentation rate and of about 0.31 to 0.34 m/ka using correlation ages from nearby shallow core. This offshore dip-slip rate is significantly lower than previous published 1.0-2.0 m/ka dip-slip rates estimated using cosmogenic dating of Tioga glacial moraines in Lundy Canyon and offset older moraines. The offset on the large scarp in Lundy Canyon (~20 m) decreases both north and south of the canyon and flanking lateral moraines where the scarp is on the order of only ~4-7 m high. A possible explanation for the apparent difference in MLfz slip rates onshore and offshore in this part of Mono Basin may be soft sediment deformation of saturated glacial-deltaic sediment within Lundy Canyon that causes

  19. Primary studies of trace quantities of green vegetation in Mono Lake area using 1990 AVIRIS data

    NASA Technical Reports Server (NTRS)

    Chen, Zhi-Kang; Elvidge, Chris D.; Groeneveld, David P.

    1992-01-01

    Our primary results in Jasper Ridge Biological Preserve indicate that high spectral resolution Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) data may provide a substantial advantage in vegetation, based on the chlorophyll red edge feature from 700-780 nm. The chlorophyll red edge was detected for green vegetation cover as low as 4.8 percent. The objective of our studies in Mono Lake area is to continue the experiments performed in Jasper Ridge and to examine the persistence of red edge feature of trace quantities of green vegetation for different plant communities with non-uniform soil backgrounds.

  20. Distribution of RuBisCO genotypes along a redox gradient in Mono Lake, California.

    PubMed

    Giri, Bruno J; Bano, Nasreen; Hollibaugh, James T

    2004-06-01

    Partial sequences of ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO) (EC 4.1.1.39) genes were retrieved from samples taken along a redox gradient in alkaline, hypersaline Mono Lake, Calif. The form I gene (cbbL) was found in all samples, whereas form II (cbbM) was not retrieved from any of the samples. None of the RuBisCO sequences we obtained were closely related (nucleotide similarity, <90%) to sequences in the database. Some could be attributed to organisms isolated from the lake (Cyanobium) or appearing in enrichment cultures. Most (52%) of the sequences fell into in one clade, containing sequences that were identical to sequences retrieved from an enrichment culture grown with nitrate and sulfide, and another clade contained sequences identical to those retrieved from an arsenate-reducing, sulfide-oxidizing enrichment.

  1. Distribution, production, and ecophysiology of Picocystis strain ML in Mono Lake, California

    USGS Publications Warehouse

    Roesler, Collin S.; Culbertson, Charles W.; Etheridge, Stacey M.; Goericke, Ralf; Kiene, Ronald P.; Miller, Laurence G.; Oremland, Ronald S.

    2002-01-01

    A recently described unicellular chlorophytic alga isolated from meromictic Mono Lake, California, occupies a niche that spans two environments: the upper oxic mixolimnion and the deeper anoxic and highly reducing monimolimnion. This organism, Picocystis sp. strain ML, accounts for nearly 25% of the primary production during the winter bloom and more than 50% at other times of the year. In incubations, it is heavily grazed by the brine shrimp, Artemia monica. We assessed growth and photosynthetic parameters over broad ranges of irradiance, salinity, and pH and under oxic and anoxic conditions. Picocystis appears to be particularly adapted to low irradiance; we observed an order of magnitude increase in the cellular pigment concentrations, as well as marked increases in cellspecific photosynthetic parameters for cells acclimated to low-growth irradiance. Growth rates of 0.3–1.5 d21 were observed over a salinity range of 0–260‰ and a pH range of 4–12, with maximal growth at ;50 mmol photons m22 s21 , 40‰, and pH 6–10. Growth and oxygenic photosynthesis were observed under anoxic conditions at rates comparable to those measured under oxic conditions. The ability of the organism to acclimate and grow under such a broad range of environmental conditions makes it an important component of the Mono Lake ecosystem and likely contributes to its dominance of the monimolimnion/mixolimnion interface.

  2. 21 CFR 172.856 - Propylene glycol mono- and diesters of fats and fatty acids.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... fatty acids. 172.856 Section 172.856 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH... diesters of fats and fatty acids. Propylene glycol mono- and diesters of fats and fatty acids may be safely... and/or fatty acids in compliance with § 172.860 and/or oleic acid derived from tall oil fatty acids...

  3. 21 CFR 172.856 - Propylene glycol mono- and diesters of fats and fatty acids.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... and/or fatty acids in compliance with § 172.860 and/or oleic acid derived from tall oil fatty acids in... fatty acids. 172.856 Section 172.856 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH... diesters of fats and fatty acids. Propylene glycol mono- and diesters of fats and fatty acids may be...

  4. 21 CFR 172.856 - Propylene glycol mono- and diesters of fats and fatty acids.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... and/or fatty acids in compliance with § 172.860 and/or oleic acid derived from tall oil fatty acids in... fatty acids. 172.856 Section 172.856 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH... diesters of fats and fatty acids. Propylene glycol mono- and diesters of fats and fatty acids may be...

  5. 21 CFR 172.856 - Propylene glycol mono- and diesters of fats and fatty acids.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... and/or fatty acids in compliance with § 172.860 and/or oleic acid derived from tall oil fatty acids in... fatty acids. 172.856 Section 172.856 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH... diesters of fats and fatty acids. Propylene glycol mono- and diesters of fats and fatty acids may be...

  6. Magmatic gas emissions at Holocene volcanic features near Mono Lake, California, and their relation to regional magmatism

    NASA Astrophysics Data System (ADS)

    Bergfeld, Deborah; Evans, William C.; Howle, James F.; Hunt, Andrew G.

    2015-02-01

    Silicic lavas have erupted repeatedly in the Mono Basin over the past few thousand years, forming the massive domes and coulees of the Mono Craters chain and the smaller island vents in Mono Lake. We report here on the first systematic study of magmatic CO2 emissions from these features, conducted during 2007-2010. Most notably, a known locus of weak steam venting on the summit of North Coulee is actually enclosed in a large area (~ 0.25 km2) of diffuse gas discharge that emits 10-14 t/d of CO2, mostly at ambient temperature. Subsurface gases sampled here are heavily air-contaminated, but after standard corrections are applied, show average δ13C-CO2 of - 4.72‰, 3He/4He of 5.89RA, and CO2/3He of 0.77 × 1010, very similar to the values in fumarolic gas from Mammoth Mountain and the Long Valley Caldera immediately to the south of the basin. If these values also characterize the magmatic gas source at Mono Lake, where CO2 is captured by the alkaline lake water, a magmatic CO2 upflow beneath the lake of ~ 4 t/d can be inferred. Groundwater discharge from the Mono Craters area transports ~ 13 t/d of 14C-dead CO2 as free gas and dissolved carbonate species, and adding in this component brings the estimated total magmatic CO2 output to 29 t/d for the two silicic systems in the Mono Basin. If these emissions reflect intrusion and degassing of underlying basalt with 0.5 wt.% CO2, a modest intrusion rate of 0.00075 km3/yr is indicated. Much higher intrusion rates are required to account for CO2 emissions from Mammoth Mountain and the West Moat of the Long Valley Caldera.

  7. Sedimentary and Volcanic Records of the Laschamp and Mono Lake Excursions from Australia and New Zealand

    NASA Astrophysics Data System (ADS)

    Ingham, E. M.; Roberts, A. P.; Turner, G. M.; Heslop, D.; Ronge, T.; Conway, C.; Leonard, G.; Townsend, D.; Tiedemann, R.; Lamy, F.; Calvert, A. T.

    2014-12-01

    Geomagnetic excursions are short-lived deviations of the geomagnetic field from the normal range of secular variation. Despite significant advances in geomagnetic excursion research over the past 20 years, fundamental questions remain concerning the typical duration and global morphology of excursional geomagnetic fields. To answer such questions, more high-resolution, chronologically well-constrained excursion records are required, particularly from the Southern Hemisphere. We present preliminary paleomagnetic records of the Laschamp (~41 ka) and Mono Lake (~35 ka) excursions from three marine sediment cores from the Bounty Trough, New Zealand margin, and complementary volcanic records of the Laschamp excursion from lavas of Mt Ruapehu, New Zealand. Relatively high sedimentation rates of 12 - 26 cm/kyr in the Bounty Trough during glacial periods allow identification of excursional field behavior at each of the studied core locations. Each core displays one or two excursional events, with rapid directional swings between stable normal polarity and reversed excursional directions, each associated with coincident relative paleointensity minima. These anomalous paleomagnetic directions are interpreted to represent the Laschamp and Mono Lake excursions, based on a combination of tephrochronology, radiocarbon dating, and cyclostratigraphy (defined from core-scanning X-ray fluorescence and magnetic susceptibility records). Beside these records, we present results from fourteen lava flows, on Mt Ruapehu, for which 40Ar-39Ar dating indicates ages of between 39 and 45 ka. The step heating 40Ar-39Ar experiments produced particularly flat age plateaus, with corresponding 2 s.d. errors mostly approaching 1 kyr. The youngest and oldest flows carry normal polarity magnetization, however six flows, dated between 41 and 43 ka, display transitional field characteristics. Three of these flows display a declination swing of around 180o, which coincides with a previously published

  8. Nitrogen fixation dynamics of two diazotrophic communities in Mono Lake, California

    USGS Publications Warehouse

    Oremland, R.S.

    1990-01-01

    Two types of diazotrophic microbial communities were found in the littoral zone of alkaline hypersaline Mono Lake, California. One consisted of anaerobic bacteria inhabiting the flocculent surface layers of sediments. Nitrogen fixation (acetylene reduction) by flocculent surface layers occurred under anaerobic conditions, was not stimulated by light or by additions of organic substrates, and was inhibited by O2, nitrate, and ammonia. The second community consisted of a ball-shaped association of a filamentous chlorophyte (Ctenocladus circinnatus) with diazotrophic, nonheterocystous cyanobacteria, as well as anaerobic bacteria (Ctenocladus balls). Nitrogen fixation by Ctenocladus balls was usually, but not always, stimulated by light. Rates of anaerobic dark fixation equaled those in the light under air. Fixation in the light was stimulated by 3-(3,4-dichlorophenyl)-1,1-dimethylurea and by propanil [N-(3,4-dichlorophenyl)propanamide]. 3-(3,4-Dichlorophenyl)-1,1-dimethyl urea-elicited nitrogenase activity was inhibited by ammonia (96%) and nitrate (65%). Fixation was greatest when Ctenocladus balls were incubated anaerobically in the light with sulfide. Dark anaerobic fixation was not stimulated by organic substrates in short-term (4-h) incubations, but was in long-term (67-h) ones. Areal estimates of benthic N2 fixation were measured seasonally, using chambers. Highest rates (~29.3 ??mol of C2H4 m-2 h-1) occurred under normal diel regimens of light and dark. These estimates indicate that benthic N2 fixation has the potential to be a significant nitrogen source in Mono Lake.

  9. Characterization of microbial arsenate reduction in the anoxic bottom waters of Mono Lake, California

    USGS Publications Warehouse

    Hoeft, S.E.; Lucas, F.; Hollibaugh, J.T.; Oremland, R.S.

    2002-01-01

    Dissimilatory reduction of arsenate (DAsR) occurs in the arsenic-rich, anoxic water column of Mono Lake, California, yet the microorganisms responsible for this observed in situ activity have not been identified. To gain insight as to which microorganisms mediate this phenomenon, as well as to some of the biogeochemical constraints on this activity, we conducted incubations of arsenate-enriched bottom water coupled with inhibition/amendment studies and Denaturing Gradient Gel Electrophoresis (DGGE) characterization techniques. DAsR was totally inhibited by filter-sterilization and by nitrate, partially inhibited (~50%) by selenate, but only slightly (~25%) inhibited by oxyanions that block sulfate-reduction (molybdate and tungstate). The apparent inhibition by nitrate, however, was not due to action as a preferred electron acceptor to arsenate. Rather, nitrate addition caused a rapid, microbial re-oxidation of arsenite to arsenate, which gave the overall appearance of no arsenate loss. A similar microbial oxidation of As(III) was also found with Fe(III), a fact that has implications for the recycling of As(V) in Mono Lake's anoxic bottom waters. DAsR could be slightly (10%) stimulated by substrate amendments of lactate, succinate, malate, or glucose, but not by acetate, suggesting that the DAsR microflora is not electron donor limited. DGGE analysis of amplified 16S rDNA gene fragments from incubated arsenate-enriched bottom waters revealed the presence of two bands that were not present in controls without added arsenate. The resolved sequences of these excised bands indicated the presence of members of the epsilon (Sulfurospirillum) and delta (Desulfovibrio) subgroups of the Proteobacteria, both of which have representative species that are capable of anaerobic growth using arsenate as their electron acceptor.

  10. 40 CFR 721.1729 - Boric acid (H3BO3), mixed esters with polyethylene glycol mono-Bu ether and polyethylene glycol...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... polyethylene glycol mono-Bu ether and polyethylene glycol mono Me ether. 721.1729 Section 721.1729 Protection... acid (H3BO3), mixed esters with polyethylene glycol mono-Bu ether and polyethylene glycol mono Me ether... identified as boric acid (H3BO3), mixed esters with polyethylene glycol mono-Bu ether and polyethylene...

  11. 40 CFR 721.1729 - Boric acid (H3BO3), mixed esters with polyethylene glycol mono-Bu ether and polyethylene glycol...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... polyethylene glycol mono-Bu ether and polyethylene glycol mono Me ether. 721.1729 Section 721.1729 Protection... acid (H3BO3), mixed esters with polyethylene glycol mono-Bu ether and polyethylene glycol mono Me ether... identified as boric acid (H3BO3), mixed esters with polyethylene glycol mono-Bu ether and polyethylene...

  12. 40 CFR 721.1729 - Boric acid (H3BO3), mixed esters with polyethylene glycol mono-Bu ether and polyethylene glycol...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... polyethylene glycol mono-Bu ether and polyethylene glycol mono Me ether. 721.1729 Section 721.1729 Protection... acid (H3BO3), mixed esters with polyethylene glycol mono-Bu ether and polyethylene glycol mono Me ether... identified as boric acid (H3BO3), mixed esters with polyethylene glycol mono-Bu ether and polyethylene...

  13. 40 CFR 721.1729 - Boric acid (H3BO3), mixed esters with polyethylene glycol mono-Bu ether and polyethylene glycol...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... polyethylene glycol mono-Bu ether and polyethylene glycol mono Me ether. 721.1729 Section 721.1729 Protection... acid (H3BO3), mixed esters with polyethylene glycol mono-Bu ether and polyethylene glycol mono Me ether... identified as boric acid (H3BO3), mixed esters with polyethylene glycol mono-Bu ether and polyethylene...

  14. 40 CFR 721.1729 - Boric acid (H3BO3), mixed esters with polyethylene glycol mono-Bu ether and polyethylene glycol...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... polyethylene glycol mono-Bu ether and polyethylene glycol mono Me ether. 721.1729 Section 721.1729 Protection... acid (H3BO3), mixed esters with polyethylene glycol mono-Bu ether and polyethylene glycol mono Me ether... identified as boric acid (H3BO3), mixed esters with polyethylene glycol mono-Bu ether and polyethylene...

  15. 21 CFR 172.856 - Propylene glycol mono- and diesters of fats and fatty acids.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... with § 172.860 and/or oleic acid derived from tall oil fatty acids in compliance with § 172.862. (b... fatty acids. 172.856 Section 172.856 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH... CONSUMPTION Multipurpose Additives § 172.856 Propylene glycol mono- and diesters of fats and fatty...

  16. Anaerobic oxidation of arsenite in Mono Lake water and by a facultative, arsenite-oxidizing chemoautotroph, strain MLHE-1.

    PubMed

    Oremland, Ronald S; Hoeft, Shelley E; Santini, Joanne M; Bano, Nasreen; Hollibaugh, Ryan A; Hollibaugh, James T

    2002-10-01

    Arsenite [As(III)]-enriched anoxic bottom water from Mono Lake, California, produced arsenate [As(V)] during incubation with either nitrate or nitrite. No such oxidation occurred in killed controls or in live samples incubated without added nitrate or nitrite. A small amount of biological As(III) oxidation was observed in samples amended with Fe(III) chelated with nitrolotriacetic acid, although some chemical oxidation was also evident in killed controls. A pure culture, strain MLHE-1, that was capable of growth with As(III) as its electron donor and nitrate as its electron acceptor was isolated in a defined mineral salts medium. Cells were also able to grow in nitrate-mineral salts medium by using H(2) or sulfide as their electron donor in lieu of As(III). Arsenite-grown cells demonstrated dark (14)CO(2) fixation, and PCR was used to indicate the presence of a gene encoding ribulose-1,5-biphosphate carboxylase/oxygenase. Strain MLHE-1 is a facultative chemoautotroph, able to grow with these inorganic electron donors and nitrate as its electron acceptor, but heterotrophic growth on acetate was also observed under both aerobic and anaerobic (nitrate) conditions. Phylogenetic analysis of its 16S ribosomal DNA sequence placed strain MLHE-1 within the haloalkaliphilic Ectothiorhodospira of the gamma-PROTEOBACTERIA: Arsenite oxidation has never been reported for any members of this subgroup of the PROTEOBACTERIA:

  17. Anaerobic oxidation of arsenite in Mono Lake water and by a facultative, arsenite-oxidizing chemoautotroph, strain MLHE-1

    USGS Publications Warehouse

    Oremland, R.S.; Hoeft, S.E.; Santini, J.M.; Bano, N.; Hollibaugh, R.A.; Hollibaugh, J.T.

    2002-01-01

    Arsenite [As(III)]-enriched anoxic bottom water from Mono Lake, California, produced arsenate [As(V)] during incubation with either nitrate or nitrite. No such oxidation occurred in killed controls or in live samples incubated without added nitrate or nitrite. A small amount of biological As(III) oxidation was observed in samples amended with Fe(III) chelated with nitrolotriacetic acid, although some chemical oxidation was also evident in killed controls. A pure culture, strain MLHE-1, that was capable of growth with As(III) as its electron donor and nitrate as its electron acceptor was isolated in a defined mineral salts medium. Cells were also able to grow in nitrate-mineral salts medium by using H2 or sulfide as their electron donor in lieu of As(III). Arsenite-grown cells demonstrated dark 14CO2 fixation, and PCR was used to indicate the presence of a gene encoding ribulose-1,5-biphosphate carboxylase/oxygenase. Strain MLHE-1 is a facultative chemoautotroph, able to grow with these inorganic electron donors and nitrate as its electron acceptor, but heterotrophic growth on acetate was also observed under both aerobic and anaerobic (nitrate) conditions. Phylogenetic analysis of its 16S ribosomal DNA sequence placed strain MLHE-1 within the haloalkaliphilic Ectothiorhodospira of the ??-Proteobacteria. Arsenite oxidation has never been reported for any members of this subgroup of the Proteobacteria.

  18. Anaerobranca californiensis sp. nov., an anaerobic, alkalithermophilic, fermentative bacterium isolated from a hot spring on Mono Lake.

    PubMed

    Gorlenko, Vladimir; Tsapin, Alexandre; Namsaraev, Zorigto; Teal, Tracy; Tourova, Tatyana; Engler, Diane; Mielke, Randy; Nealson, Kenneth

    2004-05-01

    A novel, obligately anaerobic, alkalithermophilic, chemo-organotrophic bacterium was isolated from the sediment of an alkaline hot spring located on Paoha Island in Mono Lake, California, USA. This rod-shaped bacterium was motile via peritrichous flagella. Isolated strains grew optimally in 5-25 g NaCl l(-1), at pH 9.0-9.5 and at a temperature of 58 degrees C and were fermentative and mainly proteolytic, utilizing peptone, Casamino acids and yeast extract. Optimal growth was seen in the presence of elemental sulfur, polysulfide or thiosulfate with concomitant reduction to hydrogen sulfide. Sulfite was also formed in an equal ratio to sulfide during reduction of thiosulfate. The novel isolate could also reduce Fe(III) and Se(IV) in the presence of organic matter. On the basis of physiological properties, 16S rRNA gene sequence and DNA-DNA hybridization data, strain PAOHA-1(T) (=DSM 14826(T)=UNIQEM 227(T)) belongs to the genus Anaerobranca and represents a novel species, Anaerobranca californiensis sp. nov.

  19. Bacterial dissimilatory reduction of arsenate and sulfate in meromictic Mono Lake, California

    USGS Publications Warehouse

    Oremland, R.S.; Dowdle, P.R.; Hoeft, S.; Sharp, J.O.; Schaefer, J.K.; Miller, L.G.; Switzer, Blum J.; Smith, R.L.; Bloom, N.S.; Wallschlaeger, D.

    2000-01-01

    The stratified (meromictic) water column of alkaline and hypersaline Mono Lake, California, contains high concentrations of dissolved inorganic arsenic (~200 ??mol/L). Arsenic speciation changes from arsenate [As (V)] to arsenite [As (III)] with the transition from oxic surface waters (misolimnion) to anoxic bottom waters (monimolimnion). A radioassay was devised to measure the reduction of 73As (V) to 73As (III) and tested using cell suspensions of the As (V)-respiring Bacillus selenitireducens, which completely reduced the 73As (V). In field experiments, no significant activity was noted in the aerobic mixolimnion waters, but reduction of 73As (V) to 73As (III) was observed in all the monimolimnion samples. Rate constants ranged from 0.02 to 0.3/day, with the highest values in the samples from the deepest depths (24 and 28 m). The highest activities occurred between 18 and 21 m, where As (V) abundant (rate, ~5.9 ??mol/L per day). In contrast, sulfate reduction occurred at depths below 21 m, with the highest rates attained at 28 m (rate, ~2.3 ??mol/L per day). These results indicate that As (V) ranks second in importance, after sulfate, as an electron acceptor for anaerobic bacterial respiration in the water column. Annual arsenate respiration may mineralize as much as 14.2% of the pelagic photosynthetic carbon fixed during meromixis. When combined with sulfate-reduction data, anaerobic respiration in the water column can mineralize 32-55% of this primary production. As lakes of this type approach salt saturation, As (V) can become the most important electron acceptor for the biogeochemical cycling of carbon. Copyright (C) 2000 Elsevier Science Ltd.

  20. Bacterial dissimilatory reduction of arsenate and sulfate in meromictic Mono Lake, California

    NASA Astrophysics Data System (ADS)

    Oremland, Ronald S.; Dowdle, Philip R.; Hoeft, Shelly; Sharp, Jonathan O.; Schaefer, Jeffra K.; Miller, Laurence G.; Switzer Blum, Jodi; Smith, Richard L.; Bloom, Nicholas S.; Wallschlaeger, Dirk

    2000-09-01

    The stratified (meromictic) water column of alkaline and hypersaline Mono Lake, California, contains high concentrations of dissolved inorganic arsenic (˜200 μmol/L). Arsenic speciation changes from arsenate [As (V)] to arsenite [As (III)] with the transition from oxic surface waters (mixolimnion) to anoxic bottom waters (monimolimnion). A radioassay was devised to measure the reduction of 73As (V) to 73As (III) and tested using cell suspensions of the As (V)-respiring Bacillus selenitireducens, which completely reduced the 73As (V). In field experiments, no significant activity was noted in the aerobic mixolimnion waters, but reduction of 73As (V) to 73As (III) was observed in all the monimolimnion samples. Rate constants ranged from 0.02 to 0.3/day, with the highest values in the samples from the deepest depths (24 and 28 m). The highest activities occurred between 18 and 21 m, where As (V) was abundant (rate, ˜5.9 μmol/L per day). In contrast, sulfate reduction occurred at depths below 21 m, with the highest rates attained at 28 m (rate, ˜2.3 μmol/L per day). These results indicate that As (V) ranks second in importance, after sulfate, as an electron acceptor for anaerobic bacterial respiration in the water column. Annual arsenate respiration may mineralize as much as 14.2% of the pelagic photosynthetic carbon fixed during meromixis. When combined with sulfate-reduction data, anaerobic respiration in the water column can mineralize 32-55% of this primary production. As lakes of this type approach salt saturation, As (V) can become the most important electron acceptor for the biogeochemical cycling of carbon.

  1. Reflectance spectra from eutrophic Mono Lake California, measured with the Airborne Visible and Infrared Imaging Spectrometer (AVIRIS)

    NASA Technical Reports Server (NTRS)

    Melack, John M.; Pilorz, Stuart H.

    1990-01-01

    An AVIRIS image was obtained for Mono Lake, California, on May 26, 1989, a day with excellent visibility. Atmospherically-corrected reflectance spectra derived from the image indicate a spectral signature for chlorophyll a, the dominant photosynthetic pigment in the phytoplankton of the lake. Chlorophyll a concentrations in the lake were about 22 mg/cu m, and the upwelling radiance was low with a peak reflectance at about 570 nm of about 5 percent. Coherent noise appeared in the image as regular variations of 0.1 to 0.2 microwatts/sq cm per str oriented diagonally to the flight line. A simple ratio of two spectral bands removed the conspicuous undulations, but modifications of the shielding within the instrument are needed to improve the signal especially over dark targets such as lakes.

  2. Aerobic methane oxidation and methanotroph community composition during seasonal stratification in Mono Lake, California (USA).

    PubMed

    Carini, Stephen; Bano, Nasreen; LeCleir, Gary; Joye, Samantha B

    2005-08-01

    Patterns of aerobic methane (CH4) oxidation and associated methanotroph community composition were investigated during the development of seasonal stratification in Mono Lake, California (USA). CH4 oxidation rates were measured using a tritiated CH4 radiotracer technique. Fluorescence in situ hybridization (FISH), denaturing gradient gel electrophoresis (DGGE) and sequence analysis were used to characterize methanotroph community composition. A temporally shifting zone of elevated CH4 oxidation (59-123 nM day(-1)) was consistently associated with a suboxycline, microaerophilic zone that migrated upwards in the water column as stratification progressed. FISH analysis revealed stable numbers of type I (4.1-9.3 x 10(5) cells ml(-1)) and type II (1.4-3.4 x 10(5) cells ml(-1)) methanotrophs over depth and over time. Denaturing gradient gel electrophoresis and sequence analysis indicated slight shifts in methanotroph community composition despite stable absolute cell numbers. Variable CH4 oxidation rates in the presence of a relatively stable methanotroph population suggested that zones of high CH4 oxidation resulted from an increase in activity of a subset of the existing methanotroph population. These results challenge existing paradigms suggesting that zones of elevated CH4 oxidation activity result from the accumulation of methanotrophic biomass and illustrate that type II methanotrophs may be an important component of the methanotroph population in saline and/or alkaline pelagic environments.

  3. Spirochaeta americana sp. nov.: A New Haloalkaliphilic, Obligately Anaerobic Spirochete Isolated from Soda Mono Lake, California

    NASA Technical Reports Server (NTRS)

    Hoover, Richard B.; Pikuta, Elena V.; Marsic, Damien; Whitman, William B.; Tang, Jane; Krader, Paul; Six, N. Frank (Technical Monitor)

    2002-01-01

    A novel obligately anaerobic, mesophilic, haloalkaliphilic spirochete, strain ASpG1, was isolated from sediments of the alkaline, hypersaline Mono Lake in California, U.S.A. The gram-negative cells are motile and spirochete-shaped with sizes of 0.22 x 10-15 micron. Growth was observed over the temperature range of 10 C to 44 C (optimum 37 C), NaCl concentration range of greater than 1 - 12 % (wt/vol) (optimum 3%), and pH range 7.5 - 10.5 (optimum pH 9.5). The novel isolate is strictly alkaliphilic, requires high concentrations of carbonate in the medium, and is capable of utilizing D-glucose, fructose, maltose, sucrose, starch, and D-mannitol. Main end products of glucose fermentation are: H2, acetate, ethanol, and formate. Strain AspG1 is resistant to kanamycin, but sensitive to chloramphenicol, gentamycin and tetracycline. The G+C content of its DNA is 58.5 mol%. On the basis of its physiological and molecular properties, the isolate appears to be a novel species among the genus Spirochaeta; and the name Spirochaeta americana sp. nov., is proposed for the taxon (type strain ASpG1(sup T) = ATCC BAA_392(sup T) = DSMZ 14872(sup T)).

  4. NITZSCHIA OVALIS (BACILLARIOPHYCEAE) MONO LAKE STRAIN ACCUMULATES 1,4/2,5 CYCLOHEXANETETROL IN RESPONSE TO INCREASED SALINITY(1).

    PubMed

    Garza-Sánchez, Fernando; Chapman, David J; Cooper, James B

    2009-04-01

    The growth of microalgae in hypersaline conditions requires that cells accumulate osmoprotectants. In many instances, these are polyols. We isolated the diatom Nitzschia ovalis H. J. Arn. from the saline and alkaline water body Mono Lake (CA, USA). This isolate can grow in salinities ranging from 5 to 120 parts per thousand (ppt) of salt but normally at 90 ppt salinity. In this report, we identified the major polyol osmoprotectant as 1,4/2,5 cyclohexanetetrol by electron ionization-mass spectrometry (EI-MS), (1) H, (13) C nuclear magnetic resonance spectroscopy (NMR), and infrared (IR) and showed an increase in cellular concentration in response to rising salinity. This increase in the cyclitol concentration was evaluated by gas chromatography of the derived tetraacetylated cyclohexanetetrol obtaining an average of 0.7 fmol · cell(-1) at 5 ppt and rising to 22.5 fmol · cell(-1) at 120 ppt. The 1,4/2,5 cyclohexanetetrol was also detected in the red alga Porphyridium purpureum. Analysis of the free amino acid content in N. ovalis cultures exposed to changes in salinity showed that proline and lysine also accumulate with increased salinity, but the cellular concentration of these amino acids is about 10-fold lower than the concentration of 1,4/2,5 cyclohexanetetrol. The comparison of amino acid concentration per cell with cyclitol suggests that this polyol is important in compensating the cellular osmotic pressure due to increased salinity, but other physiological functions could also be considered.

  5. Method for separating mono- and di-octylphenyl phosphoric acid esters

    DOEpatents

    Arnold, Jr., Wesley D.

    1977-01-01

    A method for separating mono-octylphenyl phosphoric acid ester and di-octylphenyl phosphoric acid ester from a mixture thereof comprises reacting the ester mixture with a source of lithium or sodium ions to form a mixture of the phosphate salts; contacting the salt mixture with an organic solvent which causes the dioctylphenyl phosphate salt to be dissolved in the organic solvent phase and the mono-octylphenyl phosphate salt to exist in a solid phase; separating the phases; recovering the phosphate salts from their respective phases; and acidifying the recovered salts to form the original phosphoric acid esters.

  6. Magmatic gas emissions at Holocene volcanic features near Mono Lake, California, and their relation to regional magmatism

    USGS Publications Warehouse

    Bergfeld, D.; Evans, William C.; Howle, James F.; Hunt, Andrew G.

    2015-01-01

    Silicic lavas have erupted repeatedly in the Mono Basin over the past few thousand years, forming the massive domes and coulees of the Mono Craters chain and the smaller island vents in Mono Lake. We report here on the first systematic study of magmatic CO2 emissions from these features, conducted during 2007–2010. Most notably, a known locus of weak steam venting on the summit of North Coulee is actually enclosed in a large area (~ 0.25 km2) of diffuse gas discharge that emits 10–14 t/d of CO2, mostly at ambient temperature. Subsurface gases sampled here are heavily air-contaminated, but after standard corrections are applied, show average δ13C-CO2 of − 4.72‰, 3He/4He of 5.89RA, and CO2/3He of 0.77 × 1010, very similar to the values in fumarolic gas from Mammoth Mountain and the Long Valley Caldera immediately to the south of the basin. If these values also characterize the magmatic gas source at Mono Lake, where CO2 is captured by the alkaline lake water, a magmatic CO2 upflow beneath the lake of ~ 4 t/d can be inferred. Groundwater discharge from the Mono Craters area transports ~ 13 t/d of 14C-dead CO2 as free gas and dissolved carbonate species, and adding in this component brings the estimated total magmatic CO2 output to 29 t/d for the two silicic systems in the Mono Basin. If these emissions reflect intrusion and degassing of underlying basalt with 0.5 wt.% CO2, a modest intrusion rate of 0.00075 km3/yr is indicated. Much higher intrusion rates are required to account for CO2 emissions from Mammoth Mountain and the West Moat of the Long Valley Caldera.

  7. Scenario earthquake hazards for the Long Valley Caldera-Mono Lake area, east-central California

    USGS Publications Warehouse

    Chen, Rui; Branum, David M.; Wills, Chris J.; Hill, David P.

    2014-01-01

    As part of the U.S. Geological Survey’s (USGS) multi-hazards project in the Long Valley Caldera-Mono Lake area, the California Geological Survey (CGS) developed several earthquake scenarios and evaluated potential seismic hazards, including ground shaking, surface fault rupture, liquefaction, and landslide hazards associated with these earthquake scenarios. The results of these analyses can be useful in estimating the extent of potential damage and economic losses because of potential earthquakes and in preparing emergency response plans. The Long Valley Caldera-Mono Lake area has numerous active faults. Five of these faults or fault zones are considered capable of producing magnitude ≥6.7 earthquakes according to the Uniform California Earthquake Rupture Forecast, Version 2 (UCERF 2) developed by the 2007 Working Group of California Earthquake Probabilities (WGCEP) and the USGS National Seismic Hazard Mapping (NSHM) Program. These five faults are the Fish Slough, Hartley Springs, Hilton Creek, Mono Lake, and Round Valley Faults. CGS developed earthquake scenarios for these five faults in the study area and for the White Mountains Fault to the east of the study area. Earthquake scenarios are intended to depict the potential consequences of significant earthquakes. They are not necessarily the largest or most damaging earthquakes possible. Earthquake scenarios are both large enough and likely enough that emergency planners should consider them in regional emergency response plans. Earthquake scenarios presented here are based on fault geometry and activity data developed by the WGCEP, and are consistent with the 2008 Update of the United States National Seismic Hazard Maps (NSHM).For the Hilton Creek Fault, two alternative scenarios were developed in addition to the NSHM scenario to account for different opinions in how far north the fault extends into the Long Valley Caldera. For each scenario, ground motions were calculated using the current standard practice

  8. Amino acids in the Tagish Lake Meteorite

    NASA Technical Reports Server (NTRS)

    Kminek, G.; Botta, O.; Glavin, D. P.; Bada, J. L.

    2002-01-01

    High-performance liquid chromatography (HPLC) based amino acid analysis of a Tagish Lake meteorite sample recovered 3 months after the meteorite fell to Earth have revealed that the amino acid composition of Tagish Lake is strikingly different from that of the CM and CI carbonaceous chondrites. We found that the Tagish Lake meteorite contains only trace levels of amino acids (total abundance = 880 ppb), which is much lower than the total abundance of amino acids in the CI Orgueil (4100 ppb) and the CM Murchison (16 900 ppb). Because most of the same amino acids found in the Tagish Lake meteorite are also present in the Tagish Lake ice melt water, we conclude that the amino acids detected in the meteorite are terrestrial contamination. We found that the exposure of a sample of Murchison to cold water lead to a substantial reduction over a period of several weeks in the amount of amino acids that are not strongly bound to the meteorite matrix. However, strongly bound amino acids that are extracted by direct HCl hydrolysis are not affected by the leaching process. Thus even if there had been leaching of amino acids from our Tagish Lake meteorite sample during its 3 month residence in Tagish Lake ice and melt water, a Murchison type abundance of endogenous amino acids in the meteorite would have still been readily detectable. The low amino acid content of Tagish Lake indicates that this meteorite originated fiom a different type of parent body than the CM and CI chondrites. The parent body was apparently devoid of the reagents such as aldehyldes/ketones, HCN and ammonia needed for the effective abiotic synthesis of amino acids. Based on reflectance spectral measurements, Tagish Lake has been associated with P- or D-type asteroids. If the Tagish Lake meteorite was indeed derived fiom these types of parent bodies, our understanding of these primitive asteroids needs to be reevaluated with respect to their potential inventory of biologically important organic compounds.

  9. Arsenite as an Electron Donor for Anoxygenic Photosynthesis: Description of Three Strains of Ectothiorhodospira from Mono Lake, California and Big Soda Lake, Nevada

    PubMed Central

    Hoeft McCann, Shelley; Boren, Alison; Hernandez-Maldonado, Jaime; Stoneburner, Brendon; Saltikov, Chad W.; Stolz, John F.; Oremland, Ronald S.

    2016-01-01

    Three novel strains of photosynthetic bacteria from the family Ectothiorhodospiraceae were isolated from soda lakes of the Great Basin Desert, USA by employing arsenite (As(III)) as the sole electron donor in the enrichment/isolation process. Strain PHS-1 was previously isolated from a hot spring in Mono Lake, while strain MLW-1 was obtained from Mono Lake sediment, and strain BSL-9 was isolated from Big Soda Lake. Strains PHS-1, MLW-1, and BSL-9 were all capable of As(III)-dependent growth via anoxygenic photosynthesis and contained homologs of arxA, but displayed different phenotypes. Comparisons were made with three related species: Ectothiorhodospira shaposhnikovii DSM 2111, Ectothiorhodospira shaposhnikovii DSM 243T, and Halorhodospira halophila DSM 244. All three type cultures oxidized arsenite to arsenate but did not grow with As(III) as the sole electron donor. DNA–DNA hybridization indicated that strain PHS-1 belongs to the same species as Ect. shaposhnikovii DSM 2111 (81.1% sequence similarity), distinct from Ect. shaposhnikovii DSM 243T (58.1% sequence similarity). These results suggest that the capacity for light-driven As(III) oxidation is a common phenomenon among purple photosynthetic bacteria in soda lakes. However, the use of As(III) as a sole electron donor to sustain growth via anoxygenic photosynthesis is confined to novel isolates that were screened for by this selective cultivation criterion. PMID:28035953

  10. Arsenite as an Electron Donor for Anoxygenic Photosynthesis: Description of Three Strains of Ectothiorhodospira from Mono Lake, California and Big Soda Lake, Nevada.

    PubMed

    Hoeft McCann, Shelley; Boren, Alison; Hernandez-Maldonado, Jaime; Stoneburner, Brendon; Saltikov, Chad W; Stolz, John F; Oremland, Ronald S

    2016-12-26

    Three novel strains of photosynthetic bacteria from the family Ectothiorhodospiraceae were isolated from soda lakes of the Great Basin Desert, USA by employing arsenite (As(III)) as the sole electron donor in the enrichment/isolation process. Strain PHS-1 was previously isolated from a hot spring in Mono Lake, while strain MLW-1 was obtained from Mono Lake sediment, and strain BSL-9 was isolated from Big Soda Lake. Strains PHS-1, MLW-1, and BSL-9 were all capable of As(III)-dependent growth via anoxygenic photosynthesis and contained homologs of arxA, but displayed different phenotypes. Comparisons were made with three related species: Ectothiorhodospira shaposhnikovii DSM 2111, Ectothiorhodospira shaposhnikovii DSM 243(T), and Halorhodospira halophila DSM 244. All three type cultures oxidized arsenite to arsenate but did not grow with As(III) as the sole electron donor. DNA-DNA hybridization indicated that strain PHS-1 belongs to the same species as Ect. shaposhnikovii DSM 2111 (81.1% sequence similarity), distinct from Ect. shaposhnikovii DSM 243(T) (58.1% sequence similarity). These results suggest that the capacity for light-driven As(III) oxidation is a common phenomenon among purple photosynthetic bacteria in soda lakes. However, the use of As(III) as a sole electron donor to sustain growth via anoxygenic photosynthesis is confined to novel isolates that were screened for by this selective cultivation criterion.

  11. Arsenite as an electron donor for anoxygenic photosynthesis: Description of three strains of Ectothiorhodospria from Mono Lake, California, and Big Soda Lake, Nevada

    USGS Publications Warehouse

    McCann, Shelley; Boren, Alison; Hernandez-Maldonado, Jaime; Stoneburner, Brendon; Saltikov, Chad W; Stolz, John F.; Oremland, Ronald S.

    2017-01-01

    Three novel strains of photosynthetic bacteria from the family Ectothiorhodospiraceae were isolated from soda lakes of the Great Basin Desert, USA by employing arsenite (As(III)) as the sole electron donor in the enrichment/isolation process. Strain PHS-1 was previously isolated from a hot spring in Mono Lake, while strain MLW-1 was obtained from Mono Lake sediment, and strain BSL-9 was isolated from Big Soda Lake. Strains PHS-1, MLW-1, and BSL-9 were all capable of As(III)-dependent growth via anoxygenic photosynthesis and contained homologs of arxA, but displayed different phenotypes. Comparisons were made with three related species: Ectothiorhodospira shaposhnikovii DSM 2111, Ectothiorhodospira shaposhnikovii DSM 243T, and Halorhodospira halophila DSM 244. All three type cultures oxidized arsenite to arsenate but did not grow with As(III) as the sole electron donor. DNA–DNA hybridization indicated that strain PHS-1 belongs to the same species as Ect. shaposhnikovii DSM 2111 (81.1% sequence similarity), distinct from Ect. shaposhnikovii DSM 243T (58.1% sequence similarity). These results suggest that the capacity for light-driven As(III) oxidation is a common phenomenon among purple photosynthetic bacteria in soda lakes. However, the use of As(III) as a sole electron donor to sustain growth via anoxygenic photosynthesis is confined to novel isolates that were screened for by this selective cultivation criterion.

  12. Tindallia californiensis sp. nov., a new anaerobic, haloalkaliphilic, spore-forming acetogen isolated from Mono Lake in California.

    PubMed

    Pikuta, Elena V; Hoover, Richard B; Bej, Asim K; Marsic, Damien; Detkova, Ekaterina N; Whitman, William B; Krader, Paul

    2003-08-01

    A novel extremely haloalkaliphilic, strictly anaerobic, acetogenic bacterium strain APO was isolated from sediments of the athalassic, meromictic, alkaline Mono Lake in California. The Gram-positive, spore-forming, slightly curved rods with sizes 0.55-0.7x1.7-3.0 microm were motile by a single laterally attached flagellum. Strain APO was mesophilic (range 10-48 degrees C, optimum of 37 degrees C); halophilic (NaCl range 1-20% (w/v) with optimum of 3-5% (w/v), and alkaliphilic (pH range 8.0-10.5, optimum 9.5). The novel isolate required sodium ions in the medium. Strain APO was an organotroph with a fermentative type of metabolism and used the substrates peptone, bacto-tryptone, casamino acid, yeast extract, l-serine, l-lysine, l-histidine, l-arginine, and pyruvate. The new isolate performed the Stickland reaction with the following amino acid pairs: proline + alanine, glycine + alanine, and tryptophan + valine. The main end product of growth was acetate. High activity of CO dehydrogenase and hydrogenase indicated the presence of a homoacetogenic, non-cycling acetyl-CoA pathway. Strain APO was resistant to kanamycin but sensitive to chloramphenicol, tetracycline, and gentamycin. The G+C content of the genomic DNA was 44.4 mol% (by HPLC method). The sequence of the 16S rRNA gene of strain APO possessed 98.2% similarity with the sequence from Tindallia magadiensis Z-7934, but the DNA-DNA hybridization value between these organisms was only 55%. On the basis of these physiological and molecular properties, strain APO is proposed to be a novel species of the genus Tindallia with the name Tindallia californiensis sp. nov., (type strain APO = ATCC BAA-393 = DSM 14871).

  13. Tindallia californiensis sp. nov., a new anaerobic, haloalkaliphilic, spore-forming acetogen isolated from Mono Lake in California

    NASA Technical Reports Server (NTRS)

    Pikuta, E. V.; Hoover, R. B.; Bej, A. K.; Marsic, D.; Detkova, E. N.; Whitman, W. B.; Krader, P.

    2003-01-01

    A novel extremely haloalkaliphilic, strictly anaerobic, acetogenic bacterium strain APO was isolated from sediments of the athalassic, meromictic, alkaline Mono Lake in California. The Gram-positive, spore-forming, slightly curved rods with sizes 0.55- 0.7x1.7-3.0 microns were motile by a single laterally attached flagellum. Strain APO was mesophilic (range 10-48 C, optimum of 37 C); halophilic (NaCl range 1-20% (w/v) with optimum of 3-5% (w/v), and alkaliphilic (pH range 8.0-10.5, optimum 9.5). The novel isolate required sodium ions in the medium. Strain APO was an organotroph with a fermentative type of metabolism and used the substrates peptone, bacto-tryptone, casamino acid, yeast extract, L-serine, L-lysine, L-histidine, L-arginine, and pyruvate. The new isolate performed the Stickland reaction with the following amino acid pairs: proline + alanine, glycine + alanine, and tryptophan + valine. The main end product of growth was acetate. High activity of CO dehydrogenase and hydrogenase indicated the presence of a homoacetogenic, non-cycling acetyl-coA pathway. Strain APO was resistant to kanamycin but sensitive to chloramphenicol, tetracycline, and gentamycin. The G+C content of the genomic DNA was 44.4 mol% (by HPLC method). The sequence of the 16s rRNA gene of strain APO possessed 98.2% similarity with the sequence from Tindullia magadiensis Z-7934, but the DNA-DNA hybridization value between these organisms was only 55%. On the basis of these physiological and molecular properties, strain APO is proposed to be a novel species of the genus Tindallia with the name Tindallia californiensis sp. nov., (type strain APO = ATCC BAA-393 - DSM 14871).

  14. Acid lakes from natural and anthropogenic causes

    SciTech Connect

    Patrick, R.; Binetti, V.P.; Halterman, S.G.

    1981-01-30

    Lakes may be acid because of natural ecological conditions or because of anthropogenic activities. Apparently there has been a recent increase in acidity of many lakes in the northeastern United States. Factors that may be contributing to this increase include the use by utilities of precipitators, sulfur scrubbers, and tall stacks; the use of petroleum; and methods of combustion of fossil fuels.

  15. Synthesis, purification, and time-dependent disposition studies of 9- or 10-mono-iodostearic acid and 9- and 10-mono-iodostearyl carnitine

    SciTech Connect

    Reed, K.W.

    1985-01-01

    The purpose of this investigation was to evaluate the potential use of radiolabeled 9- or 10-mono-iodostearyl carnitine as a perfusion and metabolic imaging agent for the heart. Radiochemical purity was achieved and determined by the use of silica gel and/or anion exchange resin chromatography. Radiochemical yields of 45-63 and 4% were obtained for the fatty acid and carnitine ester, respectively. Male albino mice were sacrificed at 2, 5, 7, 10, 15, 20, 30, and 50 minutes post-injection with either /sup 125/I 9- or 10-mono-iodostearic acid or 9- or 10-mono-iodostearyl (-) carnitine. The lungs, liver heart, kidney, spleen, pancreas, small intestine, stomach, thyroid, blood, fat, and skeletal muscle tissue were excised and assayed for levels of radioactivity in a NaI crystal well counter. The very low target-to-nontarget ratios obtained with /sup 125/I 9- or 10-mono-iodostearyl carnitine in mice strongly suggest that radioiodinated 9- or 10-mono-iodostearyl carnitine is not suitable for use as a myocardial imaging agent. However, radioiodinated 9- or 10-mono-iodostearic acid showed promise as a myocardial imaging agent and may warrant further investigation.

  16. A full-vector paleomagnetic secular variation record (PSV) from Pyramid Lake (Nevada) from 47-17 ka: Evidence for the successive Mono Lake and Laschamp Excursions

    NASA Astrophysics Data System (ADS)

    Lund, S.; Benson, L.; Negrini, R.; Liddicoat, J.; Mensing, S.

    2017-01-01

    We have carried out a paleomagnetic study of late-Pleistocene Pyramid Lake core PLC08-1 (1680 cm). Our goals were to develop a full-vector paleomagnetic secular variation (PSV) record for the core, establish a paleomagnetic chronostratigraphy for the lake based on correlation of the PSV record to other dated PSV records in the region, compare that chronostratigraphy with previously developed radiocarbon and ash chronologies, and search for evidence of the Mono Lake Excursion and Laschamp Excursion. We have recovered a full-vector PSV record (inclination, declination, relative paleointensity) for the interval 47 ka to 17 ka. Twenty radiocarbon dates and four dated ashes provided a chronostratigraphic framework for this record. We have also used the link between our PSV and other dated PSV records to develop an independent PSV chronostratigraphy for the core. The PSV chronostratigraphy is not significantly different from that estimated by the radiocarbon and ash chronologies. We note the existence of two intervals of anomalous paleomagnetic directions. The younger interval, centered at 34.1 ± 0.4 ka, has the characteristic vector component features of the Mono Lake Excursion. The older interval, centered at 40.9 ± 0.5 ka, has the characteristic paleomagnetic signature of the Laschamp Excursion. This is the first time both intervals of excursional behavior have been found in the same sediment record from the western USA. Our new PSV record also corroborates previous estimates of the Mono Lake Excursion directional field behavior (Liddicoat and Coe, 1979) and age (Benson et al., 2003).

  17. Analysis of methane monooxygenase genes in mono lake suggests that increased methane oxidation activity may correlate with a change in methanotroph community structure.

    PubMed

    Lin, Ju-Ling; Joye, Samantha B; Scholten, Johannes C M; Schäfer, Hendrik; McDonald, Ian R; Murrell, J Colin

    2005-10-01

    Mono Lake is an alkaline hypersaline lake that supports high methane oxidation rates. Retrieved pmoA sequences showed a broad diversity of aerobic methane oxidizers including the type I methanotrophs Methylobacter (the dominant genus), Methylomicrobium, and Methylothermus, and the type II methanotroph Methylocystis. Stratification of Mono Lake resulted in variation of aerobic methane oxidation rates with depth. Methanotroph diversity as determined by analysis of pmoA using new denaturing gradient gel electrophoresis primers suggested that variations in methane oxidation activity may correlate with changes in methanotroph community composition.

  18. [The new bacteriochlorophyll a-containing bacterium Roseinatronobacter monicus sp. nov. from the hypersaline soda Mono Lake (California, United States)].

    PubMed

    Boldareva, E N; Briantseva, I A; Tsapin, A; Nelson, K; Sorokin, D Iu; Turova, T P; Boĭchenko, V A; Stadnichuk, I N; Gorlenko, V M

    2007-01-01

    Two strains of pink-colored aerobic bacteriochlorophyll a-containing bacteria were isolated from aerobic (strain ROS 10) and anaerobic (strain ROS 35) zones of the water column of Mono Lake (California, United States). Cells of the bacteria were nonmotile oval gram-negative rods multiplying by binary fission by means of a constriction. No intracellular membranes were detected. Polyphosphates and poly-1-hydroxybutyric acid were the storage compounds. Pigments were represented by bacteriochlorophyll a and carotenoids of the spheroidene series. The strains were obligately aerobic, mesophilic (temperature optimum of 25-30 degrees C), alkaliphilic (pH optimum of 8.5-9.5), and halophilic (optimal NaCl concentration of 40-60 g/l). They were obligately heterotrophic and grew aerobically in the dark and in the light. Respiration was inhibited by light at wavelengths corresponding to the absorption of the cellular pigments. The substrate utilization spectra were strain-specific. In the course of organotrophic growth, the bacteria could oxidize thiosulfate to sulfate; sulfide and polysulfide could also be oxidized. The DNA G+C content was 59.4 mol % in strain ROS 10 and 59 mol % in strain ROS 35. In their phenotypic properties, the new strains were close but not identical to the alkaliphilic bacterium Roseinatronobacter thiooxidans. The distinctions in the nucleotide sequences of the 16S rRNA genes (2%) and low DNA-DNA hybridization level with Rna. thiooxidans (22-25%) allow the new strains to be assigned to a new species of the genus Roseinatronobacter, Roseinatronobacter monicus sp. nov.

  19. Patterns of volcanism, weathering, and climate history from high-resolution geochemistry of the BINGO core, Mono Lake, California, USA

    NASA Astrophysics Data System (ADS)

    Zimmerman, S. R.; Starratt, S.; Hemming, S. R.

    2012-12-01

    Mono Lake, California is a closed-basin lake on the east side of the Sierra Nevada, and inflow from snowmelt dominates the modern hydrology. Changes in wetness during the last glacial period (>12,000 years ago) and over the last 2,000 years have been extensively described, but are poorly known for the intervening period. We have recovered a 6.25 m-long core from ~3 m of water in the western embayment of Mono Lake, which is shown by initial radiocarbon dates to cover at least the last 10,000 years. The sediments of the core are variable, ranging from black to gray silts near the base, laminated olive-green silt through the center, to layers of peach-colored carbonate nodules interbedded with gray and olive silts and pea-green organic ooze. Volcanic tephras from <1 to 8 cm thick occur throughout. Results of 0.5 cm-resolution scanning-X-Ray fluoresence (XRF) analysis describe changes in lithology due to volcanism, erosion, and changing lake level and chemistry. Titanium (Ti) is chemically and biologically unreactive, and records the dominant input, from weathering of Sierra Nevada granite to the west and Miocene and Pliocene volcanic rocks of the Bodie and Adobe Hills to the north, east, and south. The rhyolitic tephras of the Mono-Inyo Craters are much lower in TiO2 than the bedrock (<0.1% vs. 1-2%), and are an unweathered source of K2O (3.5-5%), and thus form dramatic peaks in the K/Ti ratio. Calcium (Ca) and Sr are well correlated throughout the core, and normalization of both by K (detritus + tephra) corresponds with occurrence of carbonate-rich layers. These are a mixture of authigenic precipitates directly precipitated and eroded into the lake during periods of regression. The lowermost 1.5 m of the BINGO core contains the highest proportion of detrital input to Mono Lake over the last ~12,000 years, recorded by high Si, Ti, K, and Fe, in black to dark-gray, fine-grained silts above 10 cm of pure light gray silt. Based on radiocarbon dates of >10,000 calibrated

  20. 40 CFR 721.1950 - 2-Butenedioic acid (Z), mono(2-((1-oxopropenyloxy)ethyl) ester .

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...-oxopropenyloxy)ethyl) ester . 721.1950 Section 721.1950 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.1950 2-Butenedioic acid (Z), mono(2-((1-oxopropenyloxy)ethyl) ester . (a... 2-butenedioic acid (Z), mono(2-((1-oxopropenyloxy)ethyl) ester (PMN P-85-543) is subject...

  1. 40 CFR 721.1950 - 2-Butenedioic acid (Z), mono(2-((1-oxopropenyloxy)ethyl) ester .

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...-oxopropenyloxy)ethyl) ester . 721.1950 Section 721.1950 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.1950 2-Butenedioic acid (Z), mono(2-((1-oxopropenyloxy)ethyl) ester . (a... 2-butenedioic acid (Z), mono(2-((1-oxopropenyloxy)ethyl) ester (PMN P-85-543) is subject...

  2. 40 CFR 721.1950 - 2-Butenedioic acid (Z), mono(2-((1-oxopropenyloxy)ethyl) ester .

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...-oxopropenyloxy)ethyl) ester . 721.1950 Section 721.1950 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.1950 2-Butenedioic acid (Z), mono(2-((1-oxopropenyloxy)ethyl) ester . (a... 2-butenedioic acid (Z), mono(2-((1-oxopropenyloxy)ethyl) ester (PMN P-85-543) is subject...

  3. 40 CFR 721.1950 - 2-Butenedioic acid (Z), mono(2-((1-oxopropenyloxy)ethyl) ester .

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...-oxopropenyloxy)ethyl) ester . 721.1950 Section 721.1950 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.1950 2-Butenedioic acid (Z), mono(2-((1-oxopropenyloxy)ethyl) ester . (a... 2-butenedioic acid (Z), mono(2-((1-oxopropenyloxy)ethyl) ester (PMN P-85-543) is subject...

  4. 40 CFR 721.1950 - 2-Butenedioic acid (Z), mono(2-((1-oxopropenyloxy)ethyl) ester .

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...-oxopropenyloxy)ethyl) ester . 721.1950 Section 721.1950 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.1950 2-Butenedioic acid (Z), mono(2-((1-oxopropenyloxy)ethyl) ester . (a... 2-butenedioic acid (Z), mono(2-((1-oxopropenyloxy)ethyl) ester (PMN P-85-543) is subject...

  5. 40 CFR 721.3130 - Sulfuric acid, mono-C9-11-alkyl esters, sodium salts.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Sulfuric acid, mono-C9-11-alkyl esters... Specific Chemical Substances § 721.3130 Sulfuric acid, mono-C9-11-alkyl esters, sodium salts. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as...

  6. 40 CFR 721.3130 - Sulfuric acid, mono-C9-11-alkyl esters, sodium salts.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Sulfuric acid, mono-C9-11-alkyl esters... Specific Chemical Substances § 721.3130 Sulfuric acid, mono-C9-11-alkyl esters, sodium salts. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as...

  7. 40 CFR 721.3130 - Sulfuric acid, mono-C9-11-alkyl esters, sodium salts.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Sulfuric acid, mono-C9-11-alkyl esters... Specific Chemical Substances § 721.3130 Sulfuric acid, mono-C9-11-alkyl esters, sodium salts. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as...

  8. 40 CFR 721.3130 - Sulfuric acid, mono-C9-11-alkyl esters, sodium salts.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Sulfuric acid, mono-C9-11-alkyl esters... Specific Chemical Substances § 721.3130 Sulfuric acid, mono-C9-11-alkyl esters, sodium salts. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as...

  9. 40 CFR 721.3130 - Sulfuric acid, mono-C9-11-alkyl esters, sodium salts.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Sulfuric acid, mono-C9-11-alkyl esters... Specific Chemical Substances § 721.3130 Sulfuric acid, mono-C9-11-alkyl esters, sodium salts. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as...

  10. Aza-Michael Mono-addition Using Acidic Alumina under Solventless Conditions.

    PubMed

    Bosica, Giovanna; Abdilla, Roderick

    2016-06-22

    Aza-Michael reactions between primary aliphatic and aromatic amines and various Michael acceptors have been performed under environmentally-friendly solventless conditions using acidic alumina as a heterogeneous catalyst to selectively obtain the corresponding mono-adducts in high yields. Ethyl acrylate was the main acceptor used, although others such as acrylonitrile, methyl acrylate and acrylamide were also utilized successfully. Bi-functional amines also gave the mono-adducts in good to excellent yields. Such compounds can serve as intermediates for the synthesis of anti-cancer and antibiotic drugs.

  11. 21 CFR 582.4101 - Diacetyl tartaric acid esters of mono- and diglycerides of edible fats or oils, or edible fat...

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Diacetyl tartaric acid esters of mono- and... Diacetyl tartaric acid esters of mono- and diglycerides of edible fats or oils, or edible fat-forming fatty acids. (a) Product. Diacetyl tartaric acid esters of mono- and diglycerides of edible fats or oils,...

  12. 21 CFR 582.4101 - Diacetyl tartaric acid esters of mono- and diglycerides of edible fats or oils, or edible fat...

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Diacetyl tartaric acid esters of mono- and... Diacetyl tartaric acid esters of mono- and diglycerides of edible fats or oils, or edible fat-forming fatty acids. (a) Product. Diacetyl tartaric acid esters of mono- and diglycerides of edible fats or oils,...

  13. Occurrence and biomagnification of polychlorinated naphthalenes and non- and mono-ortho PCBs in Lake Ontario sediment and biota.

    PubMed

    Helm, Paul A; Gewurtz, Sarah B; Whittle, D Michael; Marvin, Chris H; Fisk, Aaron T; Tomy, Gregg T

    2008-02-15

    Biota and surface sediments collected from Lake Ontario were analyzed for polychlorinated naphthalenes (PCNs) and non- and mono-ortho-substituted polychlorinated biphenyls (n/ m-o-PCBs) to compare bioaccumulation behavior of these classes of dioxin-like chemicals in a food web from the Great Lakes. Mean sigmaPCN concentrations (tri-octaCN) ranged from 14 +/- 9 pg/g in plankton to 3500 +/- 3200 pg/g (wet weight) in lake trout while sediments contained from 21 to 38 ng/g (dry weight). Principal components analysis of PCN congener patterns indicated that chlorine substitution determined which congeners favored accumulation (e.g., CN-42, -52, -60, -66, -67, and -73), while others may be subject to metabolism. The bioaccumulative congeners exhibited similar trophic magnification factors (TMFs; 1.23-1.42) and biomagnification factors (BMFs; 5.5-8.6) to the n/m-o-PCBs for the trout/weighted diet relation, although BMFs for a benthic feeding relationship (slimy sculpin/Diporeia) indicated that the n/m-o-PCBs were more bioavailablethroughthe benthic pathway. PCNs contribute significantly to the burden of dioxin-like compounds in Lake Ontario biota, contributing between 12 and 22% of total PCN + PCB TEQ in lake trout and up to 69% in benthic organisms.

  14. The effects of recent uplift and volcanism on deposition in Mono Lake, California, from seismic-reflection (CHIRP) profiles

    NASA Astrophysics Data System (ADS)

    Colman, S. M.; Hemming, S. R.; Stine, S.; Zimmerman, S. R. H.

    2014-05-01

    About 150 km of high-resolution, seismic reflection (Compressed High-Intensity Radar Pulse) profiles (approximately 20 m penetration) were collected in Mono Lake in order to define the uppermost sedimentary architecture of the basin, which has been heavily impacted by recent volcanic, tectonic, and climatic processes. The study also provides an important background for ongoing efforts to obtain paleoenvironmental records from sediment cores in the lake. The history of four seismic-stratigraphic units in the upper 20 m of section are inferred from the data, and the interpretations are generally consistent with previous interpretations of lake history for the past 2000 years, including a major lowstand at 1941 m. No shorelines below the previously documented major lowstand at 1941 m were found. A relatively steep slope segment, whose toe is at about 1918 m, and which occurs on the southern and western margins of the deep basin of the lake, is interpreted as the relict foreset slope of deposition from prograding western tributaries. This topography is unconformably overlain by a unit of interbedded tephra and lake sediments of variable lithology, which contains tephra of the North Mono (600-625 cal yr BP) eruption in its upper part. The tephra-rich unit is overlain by a mostly massive mudflow deposit that is locally more than 18 m thick and that is distributed in a radial pattern around Paoha Island. The evidence suggests that within the past few hundred years, rapid uplift of Paoha Island through thick, preexisting lake deposits led to widespread slope failures, which created a terrain of disrupted, intact blocks near the island, and a thick, fluid mudflow beyond. As is common in mudflows, the mudflow moved up the depositional slope of the lake floor, terminating against the preexisting slopes, likely in multiple surges. Since about 1700 Common Era, fine-grained, well-laminated sediments have accumulated in the deep parts of the lake at anomalously rapid rates

  15. Acid Raindrops Keep Fallin' in My Lake.

    ERIC Educational Resources Information Center

    Journal of Chemical Education, 2003

    2003-01-01

    Demonstrates acid rain falling into lakes using vinegar and explores the effects on different types of solids such as chalk, sand, and lime. Includes instructor information and student worksheets. (YDS)

  16. Molecular analysis of the sulfate reducing and archaeal community in a meromictic soda lake (Mono Lake, California) by targeting 16S rRNA, mcrA, apsA, and dsrAB genes.

    PubMed

    Scholten, J C M; Joye, S B; Hollibaugh, J T; Murrell, J C

    2005-07-01

    Sulfate reduction is the most important process involved in the mineralization of carbon in the anoxic bottom waters of Mono Lake, an alkaline, hypersaline, meromictic Lake in California. Another important biogeochemical process in Mono Lake is thought to be sulfate-dependent methane oxidation (SDMO). However little is known about what types of organisms are involved in these processes in Mono Lake. Therefore, the sulfate-reducing and archaeal microbial community in Mono Lake was analyzed by targeting 16S rRNA, methyl-coenzyme M reductase (mcrA), adenosine-5'-phosphosulfate (apsA), and dissimilatory sulfite reductase (dsrAB) genes to investigate the sulfate-reducing and archaeal community with depth. Most of the 16S rRNA gene sequences retrieved from the samples fell into the delta-subdivision of the Proteobacteria. Phylogenetic analyses suggested that the clones obtained represented sulfate-reducing bacteria, which are probably involved in the mineralization of carbon in Mono Lake, many of them belonging to a novel line of descent in the delta-Proteobacteria. Only 6% of the sequences retrieved from the samples affiliated to the domain Euryarchaeota but did not represent Archaea, which is considered to be responsible for SDMO [Orphan et al. 2001: Appl Environ Microbiol 67:1922-1934; Teske et al.: Appl Environ Microbiol 68:1994-2007]. On the basis of our results and thermodynamic arguments, we proposed that SDMO in hypersaline environments is presumably carried out by SRB alone. Polymerase chain reaction (PCR) amplifications of the mcrA-, apsA-, and dsrAB genes in Mono Lake samples were, in most cases, not successful. Only the PCR amplification of the apsA gene was partially successful. The amplification of these functional genes was not successful because there was either insufficient "target" DNA in the samples, or the microorganisms in Mono Lake have divergent functional genes.

  17. Regional Monitoring of Acidic Lakes and Streams

    EPA Pesticide Factsheets

    This asset provides data on the acid-base status of lakes and streams. Key chemical indicators measured include: sulfate, nitrate, ammonium, chloride, Acid Neutralizing Capacity (ANC), pH, base cations, dissolved organic carbon (DOC), total aluminum. TIME and LTM are part of EPA's Environmental Monitoring and Assessment Program (EMAP). Long-term monitoring of the acid-base status (pH, ANC, SO4, NO3, NH4, DOC, base cations, Al) in lakes and streams. Monitoring is conducted in acid sensitive regions of the Eastern U.S.

  18. 21 CFR 582.4505 - Mono- and diglycerides of edible fats or oils, or edible fat-forming acids.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Mono- and diglycerides of edible fats or oils, or edible fat-forming acids. 582.4505 Section 582.4505 Food and Drugs FOOD AND DRUG ADMINISTRATION... GENERALLY RECOGNIZED AS SAFE Emulsifying Agents § 582.4505 Mono- and diglycerides of edible fats or oils,...

  19. 21 CFR 582.4505 - Mono- and diglycerides of edible fats or oils, or edible fat-forming acids.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Mono- and diglycerides of edible fats or oils, or edible fat-forming acids. 582.4505 Section 582.4505 Food and Drugs FOOD AND DRUG ADMINISTRATION... GENERALLY RECOGNIZED AS SAFE Emulsifying Agents § 582.4505 Mono- and diglycerides of edible fats or oils,...

  20. 21 CFR 582.4505 - Mono- and diglycerides of edible fats or oils, or edible fat-forming acids.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Mono- and diglycerides of edible fats or oils, or edible fat-forming acids. 582.4505 Section 582.4505 Food and Drugs FOOD AND DRUG ADMINISTRATION... GENERALLY RECOGNIZED AS SAFE Emulsifying Agents § 582.4505 Mono- and diglycerides of edible fats or oils,...

  1. 21 CFR 582.4505 - Mono- and diglycerides of edible fats or oils, or edible fat-forming acids.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Mono- and diglycerides of edible fats or oils, or edible fat-forming acids. 582.4505 Section 582.4505 Food and Drugs FOOD AND DRUG ADMINISTRATION... GENERALLY RECOGNIZED AS SAFE Emulsifying Agents § 582.4505 Mono- and diglycerides of edible fats or oils,...

  2. 21 CFR 582.4505 - Mono- and diglycerides of edible fats or oils, or edible fat-forming acids.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Mono- and diglycerides of edible fats or oils, or edible fat-forming acids. 582.4505 Section 582.4505 Food and Drugs FOOD AND DRUG ADMINISTRATION... GENERALLY RECOGNIZED AS SAFE Emulsifying Agents § 582.4505 Mono- and diglycerides of edible fats or oils,...

  3. Determination of polyfluoroalkyl phosphoric acid diesters, perfluoroalkyl phosphonic acids, perfluoroalkyl phosphinic acids, perfluoroalkyl carboxylic acids, and perfluoroalkane sulfonic acids in lake trout from the Great Lakes region.

    PubMed

    Guo, Rui; Reiner, Eric J; Bhavsar, Satyendra P; Helm, Paul A; Mabury, Scott A; Braekevelt, Eric; Tittlemier, Sheryl A

    2012-11-01

    A comprehensive method to extract perfluoroalkyl carboxylic acids, perfluoroalkane sulfonic acids, perfluoroalkyl phosphonic acids, perfluoroalkyl phosphinic acids, and polyfluoroalkyl phosphoric acid diesters simultaneously from fish samples has been developed. The recoveries of target compounds ranged from 78 % to 121 %. The new method was used to analyze lake trout (Salvelinus namaycush) from the Great Lakes region. The results showed that the total perfluoroalkane sulfonate concentrations ranged from 0.1 to 145 ng/g (wet weight) with perfluorooctane sulfonate (PFOS) as the dominant contaminant. Concentrations in fish between lakes were in the order of Lakes Ontario ≈ Erie > Huron > Superior ≈ Nipigon. The total perfluoroalkyl carboxylic acid concentrations ranged from 0.2 to 18.2 ng/g wet weight. The aggregate mean perfluorooctanoic acid (PFOA) concentration in fish across all lakes was 0.045 ± 0.023 ng/g. Mean concentrations of PFOA were not significantly different (p > 0.1) among the five lakes. Perfluoroalkyl phosphinic acids were detected in lake trout from Lake Ontario, Lake Erie, and Lake Huron with concentration ranging from non-detect (ND) to 0.032 ng/g. Polyfluoroalkyl phosphoric acid diesters were detected only in lake trout from Lake Huron, at levels similar to perfluorooctanoic acid.

  4. Dynamics of the Earth Magnetic Field during the period of high variability covering the Laschamp and Mono Lake excursions.

    NASA Astrophysics Data System (ADS)

    Laj, Carlo; Guillou, Hervé; Kissel, Catherine

    2014-05-01

    We report on a synthesis of new paleomagnetic data (direction and intensity), conducted together with new K/Ar and 40Ar/39Ar dating over the past few years on 37 lava flows from the Chaîne des Puys (Massif Central, France). New flows emplaced during the Laschamp excursion have been identified and their K/Ar and 40Ar/39Ar dating improves again the precision of the age of this excursion, now established at 41.3 ± 0.6 ka (2sigma). Also, transitional flows corresponding to the Mono Lake excursion have been identified for the first time in this region, widening the geographical expression of this excursion. Absolute intensities obtained from 22 flows out of the 35 studied flows indicate that the intensity of the earth magnetic field is highly reduced, not only during the Laschamp but also during the Mono Lake excursion (to about 10% of the present-day field value). These two well identified and well dated minima, therefore now constitute very precise and accurate tie-points for the chronostratigraphy of this time period. In the 7000 years long interval separating the two excursions, the intensity of the earth magnetic field recovers to almost non-transitional values. This rules out the recent suggestion that a long intensity minimum (6000 years) between the two excursions would have resulted in the extinction of the Neandertal man-kind, via a strong decrease of the atmospheric ozone and an increase in UVB concentration. Not only the amplitude but also the duration of the observed changes are remarkably consistent in the high resolution records obtained from marine sediments, lavas and cosmogenic isotopes from polar ice. They indicate that the duration of the Laschamp can be estimated at about 1500 years based on the intensity drop and to about 640 years based on the directional change. If an excursion is an aborted polarity state as previously suggested, this would imply a duration of only 320 years for a polarity reversal, far shorter than what is invoked in the

  5. Water-quality data for selected sites on Reversed, Rush, and Alger Creeks and Gull and Silver Lakes, Mono County, California, April 1994 to March 1995

    USGS Publications Warehouse

    Wang, Bronwen; Rockwell, G.L.; Blodgett, J.C.

    1995-01-01

    Water-quality data for selected sites on Reversed, Rush, and Alger Creeks and Gull and Silver Lakes, Mono County, California, were collected from April 1994 to March 1995. Water samples were analyzed for major ions and trace elements, nutrients, methylene blue active substances, and oil and grease. Field measurements were made for discharge, specific conductance, pH, water temperature, barometric pressure, dissolved oxygen, and alkalinity. Additional data collected include vertical water profiles of specific conductance, pH, water temperature, and dissolved oxygen collected at 3.3-foot intervals for Gull and Silver Lakes; chlorophyll-a and -b concentrations and Secchi depth for Gull and Silver Lakes; sediment interstitial- water nutrient concentrations in cores from Gull Lake; and lake surface and volume of Gull and Silver Lakes.

  6. Novel surface-active oligofructose fatty acid mono-esters by enzymatic esterification.

    PubMed

    van Kempen, Silvia E H J; Boeriu, Carmen G; Schols, Henk A; de Waard, Pieter; van der Linden, Erik; Sagis, Leonard M C

    2013-06-01

    This article describes the synthesis of a series of oligofructose monoesters with fatty acids of different chain length (C8, C12, C16 and C18) to obtain food-grade surfactants with a range of amphiphilicity. Reactions were performed in a mixture of DMSO/Bu(t)OH (10/90 v/v) at 60°C and catalysed by immobilised Candida antarctica lipase B. MALDI-TOF-MS analysis showed that the crude reaction products were mixtures of unmodified oligofructose and mostly mono-esters. The conversion into mono-esters increased with the length of the fatty acid chain, reflecting the specificity of the lipase towards more lipophilic substrates. Reverse phase solid phase extraction was used to fractionate the products, which lead to sufficient purity (>93%) of the fatty acid esters for functionality testing. It was shown that derivatives of longer (C16 and C18) fatty acids were more efficient in lowering surface tension and gave a much higher dilatational modulus than derivatives of the shorter (C8 and C12) fatty acids.

  7. 21 CFR 582.4101 - Diacetyl tartaric acid esters of mono- and diglycerides of edible fats or oils, or edible fat...

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... diglycerides of edible fats or oils, or edible fat-forming fatty acids. 582.4101 Section 582.4101 Food and... Diacetyl tartaric acid esters of mono- and diglycerides of edible fats or oils, or edible fat-forming fatty acids. (a) Product. Diacetyl tartaric acid esters of mono- and diglycerides of edible fats or oils,...

  8. 21 CFR 582.4101 - Diacetyl tartaric acid esters of mono- and diglycerides of edible fats or oils, or edible fat...

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... diglycerides of edible fats or oils, or edible fat-forming fatty acids. 582.4101 Section 582.4101 Food and... Diacetyl tartaric acid esters of mono- and diglycerides of edible fats or oils, or edible fat-forming fatty acids. (a) Product. Diacetyl tartaric acid esters of mono- and diglycerides of edible fats or oils,...

  9. 21 CFR 582.4101 - Diacetyl tartaric acid esters of mono- and diglycerides of edible fats or oils, or edible fat...

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... diglycerides of edible fats or oils, or edible fat-forming fatty acids. 582.4101 Section 582.4101 Food and... Diacetyl tartaric acid esters of mono- and diglycerides of edible fats or oils, or edible fat-forming fatty acids. (a) Product. Diacetyl tartaric acid esters of mono- and diglycerides of edible fats or oils,...

  10. Spatial characterization of acid rain stress in Canadian Shield lakes

    NASA Technical Reports Server (NTRS)

    Tanis, Fred J.

    1986-01-01

    The acidification of lake waters from airborne pollutants is of continental proportions both in North America and Europe. A major concern of the acid rain problem is the cumulative ecosystem damage to lakes and forest. The number of lakes affected in northeastern United States and on the Canadian Shield is though to be enormous. The principle objective is to examine how seasonal changes in lake water transparency are related to annual acidic load. Further, the relationship between variations in lake acidification and ecophysical units is being examined. Finally, the utility of Thematic Mapper (TM) based observations to measure seasonal changes in the optical transparency in acid lakes is being investigated.

  11. Isoquercitrin Esters with Mono- or Dicarboxylic Acids: Enzymatic Preparation and Properties

    PubMed Central

    Vavříková, Eva; Langschwager, Fanny; Jezova-Kalachova, Lubica; Křenková, Alena; Mikulová, Barbora; Kuzma, Marek; Křen, Vladimír; Valentová, Kateřina

    2016-01-01

    A series of isoquercitrin (quercetin-3-O-β-d-glucopyranoside) esters with mono- or dicarboxylic acids was designed to modulate hydro- and lipophilicity and biological properties. Esterification of isoquercitrin was accomplished by direct chemoenzymatic reaction using Novozym 435 (lipase from Candida antarctica), which accepted C5- to C12-dicarboxylic acids; the shorter ones, such as oxalic (C2), malonic (C3), succinic (C4) and maleic (C4) acids were not substrates of the lipase. Lipophilicity of monocarboxylic acid derivatives, measured as log P, increased with the chain length. Esters with glutaric and adipic acids exhibited hydrophilicity, and the dodecanedioic acid hemiester was more lipophilic. All derivatives were less able to reduce Folin–Ciocalteau reagent (FCR) and scavenge DPPH (1,1-diphenyl-2-picrylhydrazyl) than isoquercitrin; ABTS (2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid)) radical-scavenging activity was comparable. Dodecanoate and palmitate were the least active in FCR and ABTS scavenging; dodecanoate and hemiglutarate were the strongest DPPH scavengers. In contrast, most derivatives were much better inhibitors of microsomal lipoperoxidation than isoquercitrin; butyrate and hexanoate were the most efficient. Anti-lipoperoxidant activity of monocarboxylic derivatives, except acetates, decreased with increasing aliphatic chain. The opposite trend was noted for dicarboxylic acid hemiesters, isoquercitrin hemidodecanedioate being the most active. Overall, IQ butyrate, hexanoate and hemidodecanedioate are the most promising candidates for further studies. PMID:27338349

  12. The influence of mono- and divalent cations on the cardiac metabolism of arachidonic acid

    SciTech Connect

    Weis, M.T.; Malik, K.U. )

    1989-06-01

    Our previous study indicated that, in the isolated rabbit heart, perfusion with Ca2+ free Krebs Henseleit buffer (KHB) results in increased conversion of exogenous arachidonic acid to PGE2 and 6-keto-PGF1 alpha, probably as the result of increased availability of substrate to cyclooxygenase. Since perfusion with Ca2+ free buffer is known to cause alterations in the cardiac content of various mono- and divalent cations, the present study was performed to determine: (a) The relationship between the conversion of exogenous arachidonic acid to prostaglandins and cardiac content of Na+, K+, Ca2+ and Mg2+; and (b) Whether enhanced arachidonic acid conversion to prostaglandins during Ca2+ free perfusion is due to reduced incorporation of this fatty acid into tissue lipids. Perfusion of the rabbit heart with Ca2+ free buffer produced a significant reduction in the tissue content of Na+, K+, Ca2+ and Mg2+. However, the production of 6-keto-PGF1 alpha from exogenous arachidonic acid was linearly correlated with tissue Mg2+. These observations, together with our finding that perfusion with Ca2+ free KHB reduced the incorporation of (3H) arachidonic acid into tissue lipids, suggests that Ca2+ free perfusion may, by reducing the activity of arachidonyl CoA synthetase (a Mg2+ dependent enzyme), decrease the acylation of arachidonic acid into lipids, thus increasing the availability of arachidonic acid to cyclooxygenase.

  13. Isoquercitrin Esters with Mono- or Dicarboxylic Acids: Enzymatic Preparation and Properties.

    PubMed

    Vavříková, Eva; Langschwager, Fanny; Jezova-Kalachova, Lubica; Křenková, Alena; Mikulová, Barbora; Kuzma, Marek; Křen, Vladimír; Valentová, Kateřina

    2016-06-07

    A series of isoquercitrin (quercetin-3-O-β-d-glucopyranoside) esters with mono- or dicarboxylic acids was designed to modulate hydro- and lipophilicity and biological properties. Esterification of isoquercitrin was accomplished by direct chemoenzymatic reaction using Novozym 435 (lipase from Candida antarctica), which accepted C₅- to C12-dicarboxylic acids; the shorter ones, such as oxalic (C₂), malonic (C₃), succinic (C₄) and maleic (C₄) acids were not substrates of the lipase. Lipophilicity of monocarboxylic acid derivatives, measured as log P, increased with the chain length. Esters with glutaric and adipic acids exhibited hydrophilicity, and the dodecanedioic acid hemiester was more lipophilic. All derivatives were less able to reduce Folin-Ciocalteau reagent (FCR) and scavenge DPPH (1,1-diphenyl-2-picrylhydrazyl) than isoquercitrin; ABTS (2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid)) radical-scavenging activity was comparable. Dodecanoate and palmitate were the least active in FCR and ABTS scavenging; dodecanoate and hemiglutarate were the strongest DPPH scavengers. In contrast, most derivatives were much better inhibitors of microsomal lipoperoxidation than isoquercitrin; butyrate and hexanoate were the most efficient. Anti-lipoperoxidant activity of monocarboxylic derivatives, except acetates, decreased with increasing aliphatic chain. The opposite trend was noted for dicarboxylic acid hemiesters, isoquercitrin hemidodecanedioate being the most active. Overall, IQ butyrate, hexanoate and hemidodecanedioate are the most promising candidates for further studies.

  14. Volcanic hazard alert issued for the Long Valley-Mono Lake area of California

    USGS Publications Warehouse

    Kerr, R. A.

    1982-01-01

    The ski resort of Mammoth Lakes, nestled against the east front of the Sierra Nevada just east of Yosemite National Park, knows about natural hazards. It is still being shaken by an unusual sequence of earthquakes that started in 1978 and included four earthquakes of magnitude 6 within 48 hours of each other in May 1980. An earthquake hazard watch is still in effect. 

  15. An Advanced TALSPEAK Concept Using 2-Ethylhexylphosphonic Acid Mono-2-Ethylhexyl Ester as the Extractant

    SciTech Connect

    Lumetta, Gregg J.; Casella, Amanda J.; Rapko, Brian M.; Levitskaia, Tatiana G.; Pence, Natasha K.; Carter, Jennifer C.; Niver, Cynthia M.; Smoot, Margaret R.

    2014-12-21

    A method for separating the trivalent actinides and lanthanides is being developed using 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester (HEH[EHP]) as the extractant. The method is based on the preferential binding of the actinides in the aqueous phase by N-(2-hydroxyethyl)ethylenediamine-N,N',N'-triacetic acid (HEDTA), which serves to keep the actinides in the aqueous phase while the lanthanides are extracted into an organic phase containing HEH[EHP]. The process is very robust, showing little dependence upon the pH or the HEH[EHP], HEDTA, and citrate concentrations over the ranges that might be expected in a nuclear fuel recycling plant. Single-stage runs with a 2-cm centrifugal contactor indicate that modifications to the process chemistry may be needed to increase the extraction rate for Sm, Eu, and Gd. The hydraulic properties of the system are favorable to application in centrifugal contactors.

  16. 40 CFR 721.2140 - Carbo-poly-cycli-col azo-alkyl-aminoalkyl-carbo-mono-cyclic ester, halogen acid salt.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...-aminoalkyl-carbo-mono-cyclic ester, halogen acid salt. 721.2140 Section 721.2140 Protection of Environment...-aminoalkyl-carbo-mono-cyclic ester, halogen acid salt. (a) Chemical substance and significant new uses...-mino-al-kyl-car-bo-mon-o-cyc-lic ester, halogen acid salt (PMN P-88-1682) is subject to reporting...

  17. 40 CFR 721.2140 - Carbo-poly-cycli-col azo-alkyl-aminoalkyl-carbo-mono-cyclic ester, halogen acid salt.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...-aminoalkyl-carbo-mono-cyclic ester, halogen acid salt. 721.2140 Section 721.2140 Protection of Environment...-aminoalkyl-carbo-mono-cyclic ester, halogen acid salt. (a) Chemical substance and significant new uses...-mino-al-kyl-car-bo-mon-o-cyc-lic ester, halogen acid salt (PMN P-88-1682) is subject to reporting...

  18. 40 CFR 721.2140 - Carbo-poly-cycli-col azo-alkyl-aminoalkyl-carbo-mono-cyclic ester, halogen acid salt.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...-aminoalkyl-carbo-mono-cyclic ester, halogen acid salt. 721.2140 Section 721.2140 Protection of Environment...-aminoalkyl-carbo-mono-cyclic ester, halogen acid salt. (a) Chemical substance and significant new uses...-mino-al-kyl-car-bo-mon-o-cyc-lic ester, halogen acid salt (PMN P-88-1682) is subject to reporting...

  19. 40 CFR 721.2140 - Carbo-poly-cycli-col azo-alkyl-aminoalkyl-carbo-mono-cyclic ester, halogen acid salt.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...-aminoalkyl-carbo-mono-cyclic ester, halogen acid salt. 721.2140 Section 721.2140 Protection of Environment...-aminoalkyl-carbo-mono-cyclic ester, halogen acid salt. (a) Chemical substance and significant new uses...-mino-al-kyl-car-bo-mon-o-cyc-lic ester, halogen acid salt (PMN P-88-1682) is subject to reporting...

  20. 40 CFR 721.2140 - Carbo-poly-cycli-col azo-alkyl-aminoalkyl-carbo-mono-cyclic ester, halogen acid salt.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...-aminoalkyl-carbo-mono-cyclic ester, halogen acid salt. 721.2140 Section 721.2140 Protection of Environment...-aminoalkyl-carbo-mono-cyclic ester, halogen acid salt. (a) Chemical substance and significant new uses...-mino-al-kyl-car-bo-mon-o-cyc-lic ester, halogen acid salt (PMN P-88-1682) is subject to reporting...

  1. Spirochaeta americana sp. nov., a new haloalkaliphilic, obligately anaerobic spirochaete isolated from soda Mono Lake in California.

    PubMed

    Hoover, Richard B; Pikuta, Elena V; Bej, Asim K; Marsic, Damien; Whitman, William B; Tang, Jane; Krader, Paul

    2003-05-01

    A novel, obligately anaerobic, mesophilic, haloalkaliphilic spirochaete, strain ASpG1(T), was isolated from sediments of the alkaline, hypersaline Mono Lake in California, USA. Cells of the Gram-negative strain were motile and spirochaete-shaped with sizes of 0.2-0.22 x 8-18 microm. Growth of the strain was observed between 10 and 44 degrees C (optimum 37 degrees C), in 2-12% (w/v) NaCl (optimum 3% NaCl) and between pH 8 and 10.5 (optimum pH 9.5). The novel strain was strictly alkaliphilic, required high concentrations of carbonates in the medium and was capable of utilizing D-glucose, fructose, maltose, sucrose, starch and D-mannitol. End products of glucose fermentation were H2, acetate, ethanol and formate. Strain ASpG(T) was resistant to kanamycin and rifampicin, but sensitive to gentamicin, tetracycline and chloramphenicol. The G + C content of its DNA was 58.5 mol%. DNA-DNA hybridization analysis of strain ASpG1(T) with its most closely related species, Spirochaeta alkalica Z-7491(T), revealed a hybridization value of only 48.7%. On the basis of its physiological and molecular properties, strain ASpG1(T) appears to represent a novel species of the genus Spirochaeta, for which the name Spirochaeta americana is proposed (type strain ASpG1(T) =ATCC BAA-392(T) = DSM 14872(T)).

  2. Desulfonatronum paiuteum sp. nov.: A New Alkaliphilic, Sulfate-Reducing Bacterium, Isolated from Soda Mono Lake, California

    NASA Technical Reports Server (NTRS)

    Pikuta, Elena; Hoover, Richard B.; Marsic, Damien; Whitman, William; Cleland, David; Krader, Paul; Six, N. Frank (Technical Monitor)

    2002-01-01

    A novel alkaliphilic, sulfate reducing bacterium strain MLF1(sup T) was isolated from sediments of soda Mono Lake, California. Gram-negative vibrion cells, motile by singular polar flagellum, with sizes 0.5 - 0.6x 1.2 - 2.0 micron occurred singly, in pairs or short spirilla. Growth was observed over the temperature range of +15 C to +48 C (optimum +37 C), NaCl concentration range is greater than 1 - 7 %, wt/vol (optimum 3 %, wt/vol) and pH range 7.8 - 10.5 (optimum pH 9.0 - 9.4). The novel isolate is strictly alkaliphilic, requires high carbonate concentration in medium, obligately anaerobic and catalase negative. As electron donors strain MLF1(sup T) uses hydrogen, formate, ethanol. Sulfate, sulfite, and thiosulfate (but not sulfur or nitrate) can be used as electron acceptors. The sole end product of growth on formate was H2S. Strain MLF1(sup T) is resistant to kanamycin and gentamycin, but sensitive to chloramphenicol and tetracycline. Na2MoO4 inhibits growth of strain MLF1(sup T). The sum of G+C in DNA is 63.1 mol% (by HPLC method). On the basis of physiological and molecular properties, the isolate was considered as novel species of genus Desulfonatronum; and the name Desulfonatronum paiuteum sp. nov., is proposed (type strain MLF1(sup T) = ATCC BAA-395(sup T) = DSMZ 14708(sup T).

  3. Spirochaeta americana sp. nov., a new haloalkaliphilic, obligately anaerobic spirochaete isolated from soda Mono Lake in California

    NASA Technical Reports Server (NTRS)

    Hoover, Richard B.; Pikuta, Elena V.; Bej, Asim K.; Marsic, Damien; Whitman, William B.; Tang, Jane; Krader, Paul

    2003-01-01

    A novel, obligately anaerobic, mesophilic, haloalkaliphilic spirochaete, strain ASpG1(T), was isolated from sediments of the alkaline, hypersaline Mono Lake in California, USA. Cells of the Gram-negative strain were motile and spirochaete-shaped with sizes of 0.2-0.22 x 8-18 microm. Growth of the strain was observed between 10 and 44 degrees C (optimum 37 degrees C), in 2-12% (w/v) NaCl (optimum 3% NaCl) and between pH 8 and 10.5 (optimum pH 9.5). The novel strain was strictly alkaliphilic, required high concentrations of carbonates in the medium and was capable of utilizing D-glucose, fructose, maltose, sucrose, starch and D-mannitol. End products of glucose fermentation were H2, acetate, ethanol and formate. Strain ASpG(T) was resistant to kanamycin and rifampicin, but sensitive to gentamicin, tetracycline and chloramphenicol. The G + C content of its DNA was 58.5 mol%. DNA-DNA hybridization analysis of strain ASpG1(T) with its most closely related species, Spirochaeta alkalica Z-7491(T), revealed a hybridization value of only 48.7%. On the basis of its physiological and molecular properties, strain ASpG1(T) appears to represent a novel species of the genus Spirochaeta, for which the name Spirochaeta americana is proposed (type strain ASpG1(T) =ATCC BAA-392(T) = DSM 14872(T)).

  4. The Laschamp-Mono lake geomagnetic events and the extinction of Neanderthal: a causal link or a coincidence?

    NASA Astrophysics Data System (ADS)

    Valet, Jean-Pierre; Valladas, Hélène

    2010-12-01

    The causes of Neanderthal extinction and the transition with the modern man in Europe and Near East remain largely uncertain. The two main factors currently proposed are the arrival of a modern human competitor and/or the aptitude of the Neanderthals to survive rapidly changing climatic conditions. None of these hypotheses is fully satisfactory because the Neanderthals experienced other large climatic changes and the duration of overlap of the two populations remains largely unknown and even uncertain. No special attention has been given to the geomagnetic excursions of Laschamp and Mono Lake which are synchroneous with the extinction and were the most dramatic events encountered by the Neanderthals over the past 250 thousand years of their existence. During this period the geomagnetic field strength was considerably reduced and the shielding efficiency of the magnetosphere lowered, leaving energetic particles reach latitudes as low as 30°. The enhanced flux of high-energy protons (linked to solar activity) into the atmosphere yielded significant ozone depletion down to latitudes of 40-45°. A direct consequence was an increase of the UV-B radiations at the surface which might have reached at least 15-20% in Europe with significant impacts on health of human populations. We suggest that these conditions, added to some other factors, contributed to the demise of Neanderthal population.

  5. High-resolution tephrochronology of the Wilson Creek Formation (Mono Lake, California) and Laschamp event using 238U-230Th SIMS dating of accessory mineral rims

    NASA Astrophysics Data System (ADS)

    Vazquez, Jorge A.; Lidzbarski, Marsha I.

    2012-12-01

    Sediments of the Wilson Creek Formation surrounding Mono Lake preserve a high-resolution archive of glacial and pluvial responses along the eastern Sierra Nevada due to late Pleistocene climate change. An absolute chronology for the Wilson Creek stratigraphy is critical for correlating the paleoclimate record to other archives in the western U.S. and the North Atlantic region. However, multiple attempts to date the Wilson Creek stratigraphy using carbonates and tephras yield discordant results due to open-system effects and radiocarbon reservoir uncertainties as well as abundant xenocrysts. New ion microprobe 238U-230Th dating of the final increments of crystallization recorded by allanite and zircon autocrysts from juvenile pyroclasts yield ages that effectively date eruption of key tephra beds and delimit the timing of basal Wilson Creek sedimentation to the interval between 26.8±2.1 and 61.7±1.9 ka. Tephra (Ash 15) erupted during the geomagnetic excursion originally designated the Mono Lake excursion yields an age of 40.8±1.9 ka, indicating that the event is instead the Laschamp excursion. The new ages support a depositional chronology from magnetostratigraphy that indicates quasi-synchronous glacial and hydrologic responses in the Sierra Nevada and Mono Basin to regional climate change, with intervals of lake filling and glacial-snowpack melting that are in phase with peaks in spring insolation.

  6. High-resolution tephrochronology of the Wilson Creek Formation (Mono Lake, California) and Laschamp event using 238U-230Th SIMS dating of accessory mineral rims

    USGS Publications Warehouse

    Vazquez, Jorge A.; Lidzbarski, Marsha I.

    2012-01-01

    Sediments of the Wilson Creek Formation surrounding Mono Lake preserve a high-resolution archive of glacial and pluvial responses along the eastern Sierra Nevada due to late Pleistocene climate change. An absolute chronology for the Wilson Creek stratigraphy is critical for correlating the paleoclimate record to other archives in the western U.S. and the North Atlantic region. However, multiple attempts to date the Wilson Creek stratigraphy using carbonates and tephras yield discordant results due to open-system effects and radiocarbon reservoir uncertainties as well as abundant xenocrysts. New ion microprobe 238U-230Th dating of the final increments of crystallization recorded by allanite and zircon autocrysts from juvenile pyroclasts yield ages that effectively date eruption of key tephra beds and delimit the timing of basal Wilson Creek sedimentation to the interval between 26.8±2.1 and 61.7±1.9 ka. Tephra (Ash 15) erupted during the geomagnetic excursion originally designated the Mono Lake excursion yields an age of 40.8±1.9 ka, indicating that the event is instead the Laschamp excursion. The new ages support a depositional chronology from magnetostratigraphy that indicates quasi-synchronous glacial and hydrologic responses in the Sierra Nevada and Mono Basin to regional climate change, with intervals of lake filling and glacial-snowpack melting that are in phase with peaks in spring insolation.

  7. Interactions of squaric acid with DABCO mono-betaine: Structural, spectroscopic and calculation studies

    NASA Astrophysics Data System (ADS)

    Barczyński, P.; Dega-Szafran, Z.; Katrusiak, A.; Szafran, M.

    2012-04-01

    The 1:1 complex of squaric acid (3,4-dihydroxy-3-cyclobutene-1,2-dion) with DABCO mono-betaine (1-carboxymethyl-1,4-diazabicyclo[2.2.2]octane inner salt), 1, has been characterized by single-crystal X-ray analysis, FTIR and NMR spectroscopies and by DFT calculations. The crystal of 1 is triclinic, space group P1¯. Short COOH⋯O and Nsbnd H⋯O hydrogen bonds of 2.445(2) and 2.582(2) Å, respectively, link the diprotonated DABCO mono-betaine dications and squarate dianions into chain. The structure is additionally stabilized by the N+⋯O electrostatic interactions and weak Csbnd H⋯O hydrogen bonds. The FTIR spectrum shows two broad absorptions in the 3000-2000 cm-1 region assigned to the νNsbnd H⋯O vibration and in the 1900-500 cm-1 region attributed to the ν(OHO) and γ(OHO) vibrations of the short hydrogen bonds.

  8. Evaluation of mono or mixed cultures of lactic acid bacteria in type II sourdough system.

    PubMed

    Ekinci, Raci; Şimşek, Ömer; Küçükçuban, Ayca; Nas, Sebahattin

    2016-01-01

    The aim of this study was to evaluate the use of mono and mixed lactic acid bacteria (LAB) cultures to determine suitable LAB combinations for a type II sourdough system. In this context, previously isolated sourdough LAB strains with antimicrobial activity, which included Lactobacillus plantarum PFC22, Lactobacillus brevis PFC31, Pediococcus acidilactici PFC38, and Lactobacillus sanfranciscensis PFC80, were used as mono or mixed culture combinations in a fermentation system to produce type II sourdough, and subsequently in bread dough production. Compared to the monoculture fermentation of dough, the use of mixed cultures shortened the adaptation period by half. In addition, the use of mixed cultures ensured higher microbial viability, and enhanced the fruity flavor during bread dough production. It was determined that the combination of L. plantarum PFC22 + P. acidilactici PFC38 + L. sanfranciscensis PFC80 is a promising culture mixture that can be used in the production of type II sourdough systems, and that may also contribute to an increase in metabolic activity during bread production process.

  9. Mammoth Lakes earthquakes, May 25-27, 1980, Mono County, California

    SciTech Connect

    McJunkin, R.D.; Bedrossian, T.L.

    1980-09-01

    A summary of California Division of Mines and Geology activities in the Mammoth Lakes region during and following the earthquakes of May 25 to 27, 1980 is presented. The first earthquake occurred on May 25th a it had a magnitude of 6.0. During the next 16 minutes, four magnitude 4.1 to 5.0 shock and one 5.5 shock occurred. The seismic activity was the beginning of an earthquake sequence that produced 72 magnitude 4.0 to 4.9 events, six 5.0 to 5.5 events, and three events of magnitude 6.0 to 6.3 during the next 48 hours; thousands of magnitude less than or equal to 3.9 earthquakes were generated during the same time period. The regional geology of the earthquake area is discussed, including rock types, structural setting, and seismic history. Ground rupture in the area is also detailed. (JMT)

  10. Spatial characterization of acid rain stress in Canadian Shield lakes

    NASA Technical Reports Server (NTRS)

    Tanis, Fred J.

    1986-01-01

    A major concern of the acid rain problem is the cumulative ecosystem damage to lakes and forests. The number of lakes affected in northeastern United States and on the Canadian Shield is thought to be enormous. Seasonal changes in lake transparency are examined relative to annual acidic load. The relationship between variations in lake acidification and ecophysical units is being examined. Finally, the utility of Thematic Mapper (TM) based observations is being used to measure seasonal changes in the optical transparency in acid lakes.

  11. Challenges in the Synthesis of a Unique Mono-Carboxylic Acid Antibiotic (+)-Zincophorin

    PubMed Central

    Song, Zhenlei; Lohse, Andrew G.; Hsung, Richard P.

    2009-01-01

    (+)-Zincophorin, also referred to as M144255 or griseochellin, is a polyoxygenated ionophoric antibiotic that was isolated from Streptomyces griseus in 1984. It possesses strong in vivo activity against Gram-positive bacteria and Clostridium coelchii. Its methyl ester was reported in a patent as having strong inhibitory properties against influenza WSN/virus with reduced toxicity for the host cell. Its ability to strongly bind with Zn2+, which is also present in its X-ray structure, is the basis for its name. Over the last two decades, (+)-zincophorin h as attracted an impressive array of synthetic efforts including Danishefsky's first total synthesis along with two recent elegant total syntheses reported by Cossy and Miyashita as well as our own formal total synthesis. This Account provides a comparison of the different synthetic efforts on this novel mono-carboxylic acid antibiotic and documents its interesting isolation, structure determination, and biological activities. PMID:19642422

  12. Challenges in the synthesis of a unique mono-carboxylic acid antibiotic, (+)-zincophorin.

    PubMed

    Song, Zhenlei; Lohse, Andrew G; Hsung, Richard P

    2009-04-01

    (+)-Zincophorin, also referred to as M144255 or griseocholin, is a polyoxygenated ionophoric antibiotic that was isolated from Streptomyces griseus in 1984. It possesses strong in vivo activity against Gram-positive bacteria and Clostridium coelchii. Its methyl ester was reported in a patent as having strong inhibitory properties against influenza WSN/virus with reduced toxicity for the host cell. Its ability to strongly bind with Zn2+, which is also present in its X-ray structure, is the basis for its name. Over the last two decades, (+)-zincophorin has attracted an impressive array of synthetic efforts including Danishefsky's first total synthesis, along with two recent elegant total syntheses reported by Cossy and Miyashita as well as our own formal total synthesis. This review provides a comparison of the different synthetic efforts on this novel mono-carboxylic acid antibiotic and documents its interesting isolation, structure determination, and biological activities.

  13. Behavior of mono-, di-, and trihydroxyoctadecenoic acids during mashing and methods of controlling their production.

    PubMed

    Kobayashi, N; Kaneda, H; Kuroda, H; Watari, J; Kurihara, T; Shinotsuka, K

    2000-01-01

    The behavior of mono-, di-, and trihydroxyoctadecenoic acids was investigated during laboratory-scale mashing under various conditions with a view to controlling their production. Using a malt in which the lipoxygenase activity was at only a trace level (less than 0.01 U/g) or starting the mashing at a higher temperature than that conventionally used (65 degrees C instead of 48 degrees C) significantly decreased the production of these hydroxy fatty acids. Lowering the pH of the mash to inhibit lipoxygenase activity and preventing O2 uptake by the mash using carbon dioxide were also effective in reducing the amounts of these acids produced during mashing. From the viewpoint of industrial-scale beer production, the prevention of O2 uptake by the mash was selected as an appropriate method for reducing oxidation during wort production without affecting the subsequent brewing process or the taste of the finished beer. After introducing oxidation prevention procedures, the content of trihydroxyoctadecenoic acids decreased by about 30% and the foam stability and taste were improved in commercial products brewed using less than 25% malts.

  14. Egg fatty acid composition from lake trout fed two Lake Michigan prey fish species.

    USGS Publications Warehouse

    Honeyfield, D.C.; Fitzsimons, J.D.; Tillitt, D.E.; Brown, S.B.

    2009-01-01

    We previously demonstrated that there were significant differences in the egg thiamine content in lake trout Salvelinus namaycush fed two Lake Michigan prey fish (alewife Alosa pseudoharengus and bloater Coregonus hoyi). Lake trout fed alewives produced eggs low in thiamine, but it was unknown whether the consumption of alewives affected other nutritionally important components. In this study we investigated the fatty acid composition of lake trout eggs when females were fed diets that resulted in different egg thiamine concentrations. For 2 years, adult lake trout were fed diets consisting of four combinations of captured alewives and bloaters (100% alewives; 65% alewives, 35% bloaters; 35% alewives, 65% bloaters; and 100% bloaters). The alewife fatty acid profile had higher concentrations of arachidonic acid and total omega-6 fatty acids than the bloater profile. The concentrations of four fatty acids (cis-13, 16-docosadienoic, eicosapentaenoic, docosapentaenoic, and docosahexaenoic acids) were higher in bloaters than in alewives. Although six fatty acid components were higher in lake trout eggs in 2001 than in 2000 and eight fatty acids were lower, diet had no effect on any fatty acid concentration measured in lake trout eggs in this study. Based on these results, it appears that egg fatty acid concentrations differ between years but that the egg fatty acid profile does not reflect the alewife-bloater mix in the diet of adults. The essential fatty acid content of lake trout eggs from females fed alewives and bloaters appears to be physiologically regulated and adequate to meet the requirements of developing embryos.

  15. Dissimilatory arsenate reduction with sulfide as electron donor: experiments with mono lake water and Isolation of strain MLMS-1, a chemoautotrophic arsenate respirer.

    PubMed

    Hoeft, Shelley E; Kulp, Thomas R; Stolz, John F; Hollibaugh, James T; Oremland, Ronald S

    2004-05-01

    Anoxic bottom water from Mono Lake, California, can biologically reduce added arsenate without any addition of electron donors. Of the possible in situ inorganic electron donors present, only sulfide was sufficiently abundant to drive this reaction. We tested the ability of sulfide to serve as an electron donor for arsenate reduction in experiments with lake water. Reduction of arsenate to arsenite occurred simultaneously with the removal of sulfide. No loss of sulfide occurred in controls without arsenate or in sterilized samples containing both arsenate and sulfide. The rate of arsenate reduction in lake water was dependent on the amount of available arsenate. We enriched for a bacterium that could achieve growth with sulfide and arsenate in a defined, mineral medium and purified it by serial dilution. The isolate, strain MLMS-1, is a gram-negative, motile curved rod that grows by oxidizing sulfide to sulfate while reducing arsenate to arsenite. Chemoautotrophy was confirmed by the incorporation of H(14)CO(3)(-) into dark-incubated cells, but preliminary gene probing tests with primers for ribulose-1,5-biphosphate carboxylase/oxygenase did not yield PCR-amplified products. Alignment of 16S rRNA sequences indicated that strain MLMS-1 was in the delta-Proteobacteria, located near sulfate reducers like Desulfobulbus sp. (88 to 90% similarity) but more closely related (97%) to unidentified sequences amplified previously from Mono Lake. However, strain MLMS-1 does not grow with sulfate as its electron acceptor.

  16. Dissimilatory arsenate reduction with sulfide as electron donor: Experiments with Mono Lake water and isolation of strain MLMS-1, a chemoautotrophic arsenate respirer

    USGS Publications Warehouse

    Hoeft, S.E.; Kulp, T.R.; Stolz, J.F.; Hollibaugh, J.T.; Oremland, R.S.

    2004-01-01

    Anoxic bottom water from Mono Lake, California, can biologically reduce added arsenate without any addition of electron donors. Of the possible in situ inorganic electron donors present, only sulfide was sufficiently abundant to drive this reaction. We tested the ability of sulfide to serve as an electron donor for arsenate reduction in experiments with lake water. Reduction of arsenate to arsenite occurred simultaneously with the removal of sulfide. No loss of sulfide occurred in controls without arsenate or in sterilized samples containing both arsenate and sulfide. The rate of arsenate reduction in lake water was dependent on the amount of available arsenate. We enriched for a bacterium that could achieve growth with sulfide and arsenate in a defined, mineral medium and purified it by serial dilution. The isolate, strain MLMS-1, is a gram-negative, motile curved rod that grows by oxidizing sulfide to sulfate while reducing arsenate to arsenite. Chemoautotrophy was confirmed by the incorporation of H14CO3- into dark-incubated cells, but preliminary gene probing tests with primers for ribulose-1,5-biphosphate carboxylase/oxygenase did not yield PCR-amplified products. Alignment of 16S rRNA sequences indicated that strain MLMS-1 was in the ??-Proteobacteria, located near sulfate reducers like Desulfobulbus sp. (88 to 90% similarity) but more closely related (97%) to unidentified sequences amplified previously from Mono Lake. However, strain MLMS-1 does not grow with sulfate as its electron acceptor.

  17. Dissimilatory arsenate reduction with sulfide as the electron donor--Experiments with Mono Lake water and isolation of strain MLMS-1, a chemoautotrophic arsenate-respirer

    USGS Publications Warehouse

    Hoeft, Shelley E.; Kulp, Thomas R.; Stolz, John F.; Hollibaugh, James T.; Oremland, Ronald S.

    2004-01-01

    Anoxic bottom water from Mono Lake, California, can biologically reduce added arsenate without any addition of electron donors. Of the possible in situ inorganic electron donors present, only sulfide was sufficiently abundant to drive this reaction. We tested the ability of sulfide to serve as an electron donor for arsenate reduction in experiments with lake water. Reduction of arsenate to arsenite occurred simultaneously with the removal of sulfide. No loss of sulfide occurred in controls without arsenate or in sterilized samples containing both arsenate and sulfide. The rate of arsenate reduction in lake water was dependent on the amount of available arsenate. We enriched for a bacterium that could achieve growth with sulfide and arsenate in a defined, mineral medium and purified it by serial dilution. The isolate, strain MLMS-1, is a gram-negative, motile curved rod that grows by oxidizing sulfide to sulfate while reducing arsenate to arsenite. Chemoautotrophy was confirmed by the incorporation of H14CO3− into dark-incubated cells, but preliminary gene probing tests with primers for ribulose-1,5-biphosphate carboxylase/oxygenase did not yield PCR-amplified products. Alignment of 16S rRNA sequences indicated that strain MLMS-1 was in the δ-Proteobacteria, located near sulfate reducers like Desulfobulbus sp. (88 to 90% similarity) but more closely related (97%) to unidentified sequences amplified previously from Mono Lake. However, strain MLMS-1 does not grow with sulfate as its electron acceptor.

  18. The Mono Lake geomagnetic excursion recorded in loess: Its application as time marker and implications for its geomagnetic nature

    NASA Astrophysics Data System (ADS)

    Hambach, U.; Hark, M.; Zeeden, C.; Reddersen, B.; Zöller, L.; Fuchs, M.

    2009-04-01

    One of the youngest and worldwide documented geomagnetic excursions in the Brunhes Chron is the Mono Lake excursion (MLE). It has been detected in marine and terrestrial sedimentary archives as well as in lavas. Recent age determinations and age estimates for the MLE centre around an age interval of approximately 31 - 34 ka. Likewise the Laschamp excursion the MLE goes along with a distinct peak in cosmogenic radionuclides in ice cores and sedimentary archives. It provides therefore an additional geomagnetic time marker for various geoarchives to synchronise different climate archives. Here we report on a detailed record of the MLE from a loess site at Krems, Lower Austria. The site is situated on the southern slope of the Wachtberg hill in the vicinity of the old city centre of Krems. The archive comprises Middle to Upper Würmian (Late Pleistocene) loess in which an Upper Palaeolithic (Early Gravettian) cultural layer is embedded. The most spectacular finds are a double infant burial found in 2005 and a single burial discovered in 2006 (Einwögerer et al., 2006). Generally, archaeological findings show an extraordinarily good preservation due to embedding in rapidly sedimented loess (Händel et al., 2008). The about 10 m thick loess pile consists of calcareous sandy, coarse silt which is rich in mica indicating local sources. It is well stratified with brownish horizons representing embryonic soils pointing to incipient pedogenesis. Some of the pedo-horizons show occasionally indications of minor erosion and bedding-parallel sediment transport, but no linear erosional features. Pale greyish horizons are the result of partial gleying under permafrost conditions. No strong pedogenesis including decalcification and clay formation is present. The cultural layer is still covered by more than 5 m of loess, and dated by radiocarbon to ~27 ka 14C BP (Einwögerer et al., 2006). Below this layer up to 2.5 m of loess resting on Lower Pleistocene fluvial gravels are

  19. 40 CFR 721.1645 - Benzenesulfonic acid, 4-methyl-, reaction products with oxirane mono[(C10-16-alkyloxy)methyl...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...-, reaction products with oxirane mono derivatives and 2,2,4(or 2,4,4)-trimethyl-1,6-hexanediamine. 721.1645... Substances § 721.1645 Benzenesulfonic acid, 4-methyl-, reaction products with oxirane mono derivatives and 2... to reporting. (1) The chemical substance benzenesulfonic acid, 4-methyl-, reaction products...

  20. 40 CFR 721.1645 - Benzenesulfonic acid, 4-methyl-, reaction products with oxirane mono[(C10-16-alkyloxy)methyl...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...-, reaction products with oxirane mono derivatives and 2,2,4(or 2,4,4)-trimethyl-1,6-hexanediamine. 721.1645... Substances § 721.1645 Benzenesulfonic acid, 4-methyl-, reaction products with oxirane mono derivatives and 2... to reporting. (1) The chemical substance benzenesulfonic acid, 4-methyl-, reaction products...

  1. 40 CFR 721.1645 - Benzenesulfonic acid, 4-methyl-, reaction products with oxirane mono[(C10-16-alkyloxy)methyl...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...-, reaction products with oxirane mono derivatives and 2,2,4(or 2,4,4)-trimethyl-1,6-hexanediamine. 721.1645... Substances § 721.1645 Benzenesulfonic acid, 4-methyl-, reaction products with oxirane mono derivatives and 2... to reporting. (1) The chemical substance benzenesulfonic acid, 4-methyl-, reaction products...

  2. 40 CFR 721.1645 - Benzenesulfonic acid, 4-methyl-, reaction products with oxirane mono[(C10-16-alkyloxy)methyl...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...-, reaction products with oxirane mono derivatives and 2,2,4(or 2,4,4)-trimethyl-1,6-hexanediamine. 721.1645... Substances § 721.1645 Benzenesulfonic acid, 4-methyl-, reaction products with oxirane mono derivatives and 2... to reporting. (1) The chemical substance benzenesulfonic acid, 4-methyl-, reaction products...

  3. 40 CFR 721.1645 - Benzenesulfonic acid, 4-methyl-, reaction products with oxirane mono[(C10-16-alkyloxy)methyl...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...-, reaction products with oxirane mono derivatives and 2,2,4(or 2,4,4)-trimethyl-1,6-hexanediamine. 721.1645... Substances § 721.1645 Benzenesulfonic acid, 4-methyl-, reaction products with oxirane mono derivatives and 2... to reporting. (1) The chemical substance benzenesulfonic acid, 4-methyl-, reaction products...

  4. Gas phase measurements of mono-fluoro-benzoic acids and the dimer of 3-fluoro-benzoic acid

    SciTech Connect

    Daly, Adam M.; Carey, Spencer J.; Pejlovas, Aaron M.; Li, Kexin; Kukolich, Stephen G.; Kang, Lu

    2015-04-14

    The microwave spectrum of the mono-fluoro-benzoic acids, 2-fluoro-, 3-fluoro-, and 4-fluoro-benzoic acid have been measured in the frequency range of 4-14 GHz using a pulsed beam Fourier transform microwave spectrometer. Measured rotational transition lines were assigned and fit using a rigid rotor Hamiltonian. Assignments were made for 3 conformers of 2-fluorobenzoic acid, 2 conformers of 3-fluorobenzoic acid, and 1 conformer of 4-fluorobenzoic acid. Additionally, the gas phase homodimer of 3-fluorobenzoic acid was detected, and the spectra showed evidence of proton tunneling. Experimental rotational constants are A(0{sup +}) = 1151.8(5), B(0{sup +}) = 100.3(5), C(0{sup +}) = 87.64(3) MHz and A(0{sup −}) = 1152.2(5), B(0{sup −}) = 100.7(5), C(0{sup −}) = 88.85(3) MHz for the two ground vibrational states split by the proton tunneling motion. The tunneling splitting (ΔE) is approximately 560 MHz. This homodimer appears to be the largest carboxylic acid dimer observed with F-T microwave spectroscopy.

  5. Spirochaeta Americana Sp. Nov., A new Haloalkaliphilic, Obligately Anaerobic Spirochete Isolated from Soda Mono Lake in California

    NASA Technical Reports Server (NTRS)

    Hoover, Richard B.; Pikuta, Elena V.; Bej, Asim K.; Marsic, Damien; Whitman, William B.; Tang, Jane; Krader, Paul; Six, N. Frank (Technical Monitor)

    2002-01-01

    A novel obligately anaerobic, mesophilic, haloalkaliphilic spirochete, strain ASpG1(sup T), was isolated from sediments of the alkaline, hypersaline Mono Lake in California, U.S.A. The Gram-negative cells are motile and spirochete-shaped with sizes of 0.2 - 0.22 X 8-15 microns. Growth was observed over the following ranges: temperature 10 C to 44 C; optimum +37 C; NaCl concentration 2 - 12 % (w/v); optimum NaCl3 % and pH 8 - 10.5; optimum pH 9.5. The novel isolate is strictly alkaliphilic, requires high concentrations of carbonate in the medium, and is capable of utilizing D-glucose, fructose, maltose, sucrose, starch, and D-mannitol. The main end products of glucose fermentation are: H2, acetate, ethanol, and formate. Strain ASpG(sup T) is resistant to kanamycin, and rifampin, but sensitive to chloramphenicol, gentamycin and tetracycline. The G+C content of its DNA is 58.5 mol%, genome size is 2.98 x l0(exp 9) Daltons, Tm of the genomic DNA is 68 +/- 2 C, and DNA-DNA hybridization with the most closely related species, Spirocheta alkalica Strain Z-7491(sup T), exhibited 48.7% homology. On the basis of its physiological and molecular properties, the isolate appears to be a novel species of the genus Spirochaeta; and the name Spirochaeta americana sp. nov., is proposed for the taxon (type strain ASpG1(sup T) = ATCC BAA-392(sup T) = DSMZ 14872(sup T)).

  6. Spatial characterization of acid rain stress in Canadian Shield Lakes

    NASA Technical Reports Server (NTRS)

    Tanis, F. J.; Marshall, E. M.

    1989-01-01

    The lake acidification in Northern Ontario was investigated using LANDSAT TM to sense lake volume reflectance and also to provide important vegetation and terrain characteristics. The purpose of this project was to determine the ability of LANDSAT to assess water quality characteristics associated with lake acidification. Results demonstrate that a remote sensor can discriminate lake clarity based upon reflection. The basic hypothesis is that seasonal and multi-year changes in lake optical transparency are indicative of sensitivity to acidic deposition. In many acid-sensitive lakes optical transparency is controlled by the amount of dissolved organic carbon present. Seasonal changes in the optical transparency of lakes can potentially provide an indication of the stress due to acid deposition and loading.

  7. Hydrogeologic controls on the groundwater interactions with an acidic lake in karst terrain, Lake Barco, Florida

    USGS Publications Warehouse

    Lee, T.M.

    1996-01-01

    Transient groundwater interactions and lake stage were simulated for Lake Barco, an acidic seepage lake in the mantled karst of north central Florida. Karst subsidence features affected groundwater flow patterns in the basin and groundwater fluxes to and from the lake. Subsidence features peripheral to the lake intercepted potential groundwater inflow and increased leakage from the shallow perimeter of the lake bed. Simulated groundwater fluxes were checked against net groundwater flow derived from a detailed lake hydrologic budget with short-term lake evaporation computed by the energy budget method. Discrepancies between modeled and budget- derived net groundwater flows indicated that the model underestimated groundwater inflow, possibly contributed to by transient water table mounding near the lake. Recharge from rainfall reduced lake leakage by 10 to 15 times more than it increased groundwater inflow. As a result of the karst setting, the contributing groundwater basin to the lake was 2.4 ha for simulated average rainfall conditions, compared to the topographically derived drainage basin area of 81 ha. Short groundwater inflow path lines and rapid travel times limit the contribution of acid-neutralizing solutes from the basin, making Lake Barco susceptible to increased acidification by acid rain.

  8. Chemical hazards from acid crater lakes

    NASA Astrophysics Data System (ADS)

    van Bergen, M. J.; Sumarti, S.; Heikens, A.; Bogaard, T. A.; Hartiyatun, S.

    2003-04-01

    Acid crater lakes, which are hosted by a considerable number of active volcanoes, form a potential threat for local ecosystems and human health, as they commonly contain large amounts of dissolved chemicals. Subsurface seepage or overflow can lead to severe deterioration of the water quality of rivers and wells, as observations around several of these volcanoes have shown. The Ijen crater lake in East Java (Indonesia) is a striking example, as this reservoir of hyperacid (pH<0.5) sulphate, chloride and fluoride-rich water is the source of a ca. 50 km long acid river that transports substantial quantities of potentially toxic elements. A downstream trend of increasing pH from <1 to 2.5-4 is largely due to dilution with moderately acid springs (pH= ca. 4) and neutral tributaries (pH= ca. 7) inside the Ijen caldera. Geochemical controls that regulate element transport are subject to seasonal fluctuations in rainfall. Long-term monitoring has shown that fluoride levels pose some of the most severe environmental threats. Its concentration decreases from ca. 1300 mg/kg in the lake to ca. 10 mg/kg in a coastal area downstream, where virtually all of the river water is used for irrigating rice fields and other cropland. Apart from serious problems for agriculture, our survey of 55 drinking water wells in the irrigation area shows that 50% contain fluoride above the 1.5 ppm WHO limit, in line with the observation that dental fluorosis is widespread among the ca. 100,000 residents of the area. A conspicuous spatial correlation between fluoride concentrations and the irrigation system suggest that long-term (century) infiltration of irrigation water may have affected the quality of groundwater. Fluorosis is also a problem in some villages within the caldera, where well water sources may have a more direct subsurface connection with the lake system. From our observations we conclude that water-quality monitoring is especially needed for health reasons in volcanic areas where

  9. Tindallia Californiensis sp. nov.: A New Halo-Alkaliphilic Primary Anaerobe, Isolated from Meromictic soda Mono Lake in California and the Correction of Diagnosis for Genus Tindallia

    NASA Technical Reports Server (NTRS)

    Pikuta, Elena; Marsic, Damien; Hoover, Richard B.; Kevbrin, Vadim; Whitman, William B.; Krader, Paul; Cleland, Dave; Six, N. Frank (Technical Monitor)

    2002-01-01

    A novel extremely halo-alkaliphilic, bacterium strain APO (sup T) was isolated from sediments of the athalassic, meromictic, soda Mono Lake in California. Gram positive, spore-forming, slightly curved rods with sizes 0.6-0.7x 2.5-4.0 micrometers which occur singly, in pairs or short curved chains. Cells, are motile by singular subcentral flagellum. Strain APO (sup T) is mesophilic: growth was observed over the temperature range of +10 C to +48 C (optimum +37 C), NaCl concentration range 1-20 %, wt/vol (optimum 3-5%, wt/vol) and pH range 8.0-11.0 (optimum pH 9.5). The novel isolate is strictly halo-alkaliphilic, requires sodium chloride in medium, obligately anaerobic and catalase-negative. Strain APO (sup T) is organo-heterotroph with fermentative type of metabolism, and uses as substrates: peptone, badotryptone, casamino acids, yeast extract, L-serine, L-lysine, L-histidine, L-arginine, and pyruvate. The main end products of growth on peptone medium were: lactate, acetate, propionate, and ethanol. Strain APO (sup T) is resistant to kanamycin, but sensitive to chloramphenicol, tetracycline, and gentamycin. The sum of G+C in DNA is 44.4 mol% (by HPLC method). On the bait of physiological and molecular properties, the isolate was considered as novel species of genus Tindallia; and the name Tindallia californiensis sp. nov., is proposed for new isolate (type strain APO (sup T) - ATCC BAA_393(sup T) = DSMZ 14871 (sup T)).

  10. In vivo vizualisation of mono-ADP-ribosylation by dPARP16 upon amino-acid starvation

    PubMed Central

    Aguilera-Gomez, Angelica; van Oorschot, Marinke M; Veenendaal, Tineke; Rabouille, Catherine

    2016-01-01

    PARP catalysed ADP-ribosylation is a post-translational modification involved in several physiological and pathological processes, including cellular stress. In order to visualise both Poly-, and Mono-, ADP-ribosylation in vivo, we engineered specific fluorescent probes. Using them, we show that amino-acid starvation triggers an unprecedented display of mono-ADP-ribosylation that governs the formation of Sec body, a recently identified stress assembly that forms in Drosophila cells. We show that dPARP16 catalytic activity is necessary and sufficient for both amino-acid starvation induced mono-ADP-ribosylation and subsequent Sec body formation and cell survival. Importantly, dPARP16 catalyses the modification of Sec16, a key Sec body component, and we show that it is a critical event for the formation of this stress assembly. Taken together our findings establish a novel example for the role of mono-ADP-ribosylation in the formation of stress assemblies, and link this modification to a metabolic stress. DOI: http://dx.doi.org/10.7554/eLife.21475.001 PMID:27874829

  11. Drainage basin control of acid loadings to two Adirondack lakes

    NASA Astrophysics Data System (ADS)

    Booty, W. G.; Depinto, J. V.; Scheffe, R. D.

    1988-07-01

    Two adjacent Adirondack Park (New York) calibrated watersheds (Woods Lake and Cranberry Pond), which receive identical atmospheric inputs, generate significantly different unit area of watershed loading rates of acidity to their respective lakes. A watershed acidification model is used to evaluate the watershed parameters which are responsible for the observed differences in acid loadings to the lakes. The greater overall mean depth of overburden on Woods Lake watershed, which supplies a greater buffer capacity as well as a longer retention time of groundwater, appears to be the major factor responsible for the differences.

  12. Mono Lake Saved.

    ERIC Educational Resources Information Center

    Kaye, Roger

    1995-01-01

    Describes the story of a Yup'ik Eskimo man who works as Native liaison for the Yukon Delta National Wildlife Refuge in Alaska to help subsistence hunters grasp the notion of international waterfowl management and to make clear why Yup'ik people must join sport hunters in accepting harvest reductions of declining species. (LZ)

  13. Noncatalytic mono-N-methylation of aniline in supercritical methanol: the kinetics and acid/base effect.

    PubMed

    Takebayashi, Yoshihiro; Morita, Yoshinori; Sakai, Hideki; Abe, Masahiko; Yoda, Satoshi; Furuya, Takeshi; Sugeta, Tsutomu; Otake, Katsuto

    2005-08-21

    Aniline is easily N-methylated in supercritical methanol without catalyst at 350 degrees C and 0.237 g cm-3 to give mono-N-methylaniline with high selectivity, and the reaction rate is increased by a small amount of base (LiOH, NaOH, KOH, and CH3ONa), indicating a difference in the reaction mechanism from the ordinary acid-catalyzed one.

  14. Microbiology and chemistry of acid lakes in Florida

    SciTech Connect

    James, R.T.

    1989-01-01

    Effects of acid precipitation, low pH, and dissolved organic carbon (DOC), on lake chemistry and microbiology were investigated spatially - in 5 clear and 5 dark lakes, temporally - in 3 clear and 2 dark lakes over a 2 year period, and experimentally - in enclosures to investigate effects of various acid manipulations. Spatial studies found significant positive relationships among DOC, chlorophyll a, pH, and bacterial densities. Using all data, a subsidy stress curve was observed between DOC and bacteria, further indicating toxicity of DOC at high concentrations. Temporal studies found no consistent or significant relationships between pH and bacterial densities, bacterial biomass, chlorophyll a, and protozoans. Clear lake pH was negatively related to rainfall and acid deposition. Acid deposition was also negatively related to glucose assimilation by surface water bacteria, indicating a stress on bacteria. Experimental studies examined effects of pulsed and gradual acid additions on microbial communities of a clear and dark lake. Bacteria biomass and density did not decline in response to any acid addition. Decrease uptake of both glucose and thymidine was observed in the clear-lake pulsed treatment. Chlorophyll a and protozoans declined in the dark lake pulsed treatment but not in others, indicating that pulsed additions of acid were more detrimental to the microbial community than gradual additions to the same pH.

  15. Resolving the age of Wilson Creek Formation tephras and the Mono Lake excursion using high-resolution SIMS dating of allanite and zircon rims

    NASA Astrophysics Data System (ADS)

    Vazquez, J. A.; Lidzbarski, M. I.

    2012-12-01

    Sediments of the Wilson Creek Formation surrounding Mono Lake preserve a high-resolution archive of glacial and pluvial responses along the eastern Sierra Nevada due to late Pleistocene climate change. An absolute chronology for the Wilson Creek stratigraphy is critical for correlating the paleoclimate record to other archives in the western U.S. and the North Atlantic region. However, multiple attempts to date the Wilson Creek stratigraphy using carbonates and interbedded rhyolitic tephras yield discordant 14C and 40Ar/39Ar results due to open-system effects, carbon reservoir uncertainties, as well as abundant xenocrysts entrained during eruption. Ion microprobe (SIMS) 238U-230Th dating of the final increments of crystallization recorded by allanite and zircon autocrysts from juvenile pyroclasts yields ages that effectively date eruption of key tephra beds and resolve age uncertainties about the Wilson Creek stratigraphy. To date the final several micrometers of crystal growth, individual allanite and zircon crystals were embedded in soft indium to allow sampling of unpolished rims. Isochron ages derived from rims on coexisting allanite and zircon (± glass) from hand-selected pumiceous pyroclasts delimit the timing of Wilson Creek sedimentation between Ashes 7 and 19 (numbering of Lajoie, 1968) to the interval between ca. 27 to ca. 62 ka. The interiors of individual allanite and zircon crystals sectioned in standard SIMS mounts yield model 238U-230Th ages that are mostly <10 k.y. older than their corresponding rim age, suggesting a relatively brief interval of allanite + zircon crystallization before eruption. A minority of allanite and zircon crystals yield rim and interior model ages of ca. 90-100 ka, and are likely to be antecrysts recycled from relatively early Mono Craters volcanism and/or intrusions. Tephra (Ash 15) erupted during the geomagnetic excursion originally designated the Mono Lake excursion yields a rim isochron age of ca. 41 ka indicating that

  16. Thioalkalimicrobium cyclicum sp. nov. and Thioalkalivibrio jannaschii sp. nov., novel species of haloalkaliphilic, obligately chemolithoautotrophic sulfur-oxidizing bacteria from hypersaline alkaline Mono Lake (California).

    PubMed

    Sorokin, Dimitry Yu; Gorlenko, Vladimir M; Tourova, Tat'yana P; Tsapin, Alexandre I; Nealson, Kenneth H; Kuenen, Gijs J

    2002-05-01

    Two strains of haloalkaliphilic, obligately autotrophic, sulfur-oxidizing bacteria were isolated from the oxygen-sulfide interface water layer of stratified alkaline and saline Mono Lake, California, USA. Strain ALM 1T was a dominant species in enrichment on moderate-saline, carbonate-buffered medium (0.6 M total Na+, pH 10) with thiosulfate as an energy source and nitrate as a nitrogen source. Cells of ALM 1T are open ring-shaped and are non-motile. It has a high growth rate and activity of thiosulfate and sulfide oxidation and very low sulfur-oxidizing activity. Genetic comparison and phylogenetic analysis suggested that ALM 1T (= DSM 14477T = JCM 11371T) represents a new species of the genus Thioalkalimicrobium in the gamma-Proteobacteria, for which the name Thioalkalimicrobium cyclicum sp. nov. is proposed. Another Mono Lake isolate, strain ALM 2T, dominated in enrichment on a medium containing 2 M total Na+ (pH 10). It is a motile vibrio which tolerates up to 4 M Na+ and produces a membrane-bound yellow pigment. Phylogenetic analysis placed ALM 2T as a member of genus Thioalkalivibrio in the gamma-Proteobacteria, although its DNA hybridization with the representative strains of this genus was only about 30%. On the basis of genetic and phenotypic properties, strain ALM 2T (= DSM 14478T = JCM 11372T) is proposed as Thioalkalivibrio jannaschii sp. nov..

  17. The trophodynamics of PCBs, including mono- and non-ortho congeners, in the food web of North-Central Lake Ontario.

    PubMed

    Metcalfe, T L; Metcalfe, C D

    1997-08-18

    The distribution of polychlorinated biphenyls (PCBs) in the food-web of Lake Ontario was studied to determine the parameters that control the trophodynamics of PCB congeners; including toxic non-ortho and mono-ortho PCBs. 'Biomagnification' of PCBs was evident in the food-web as total PCBs increased through trophic levels when concentrations were calculated on both a wet wt. and lipid weight basis; although there was no evidence of biomagnification between forage fish and piscivorous fish. Biomagnification was greatest for congeners with log octanol-water partition (log Kow) coefficients between 6 and 7.5. Non-ortho congeners 77 and 126, and congener 151 were not biomagnified to the extent of other congeners with similar Kow, which was attributed to high rates of metabolic clearance of these compounds. The Toxic Equivalent Quantities (TEQs) associated with non-ortho and mono-ortho PCBs increased throughout the Lake Ontario food-web. The high TEQ observed in herring gull eggs was primarily the result of very high concentrations of congener 126 in this component of the food web.

  18. Lake morphometry and wind exposure may shape the plankton community structure in acidic mining lakes.

    PubMed

    Weithoff, Guntram; Moser, Michael; Kamjunke, Norbert; Gaedke, Ursula; Weisse, Thomas

    2010-05-01

    Acidic mining lakes (pH <3) are specific habitats exhibiting particular chemical and biological characteristics. The species richness is low and mixotrophy and omnivory are common features of the plankton food web in such lakes. The plankton community structure of mining lakes of different morphometry and mixing type but similar chemical characteristics (Lake 130, Germany and Lake Langau, Austria) was investigated. The focus was laid on the species composition, the trophic relationship between the phago-mixotrophic flagellate Ochromonas sp. and bacteria and the formation of a deep chlorophyll maximum along a vertical pH-gradient. The shallow wind-exposed Lake 130 exhibited a higher species richness than Lake Langau. This increase in species richness was made up mainly by mero-planktic species, suggesting a strong benthic/littoral - pelagic coupling. Based on the field data from both lakes, a nonlinear, negative relation between bacteria and Ochromonas biomass was found, suggesting that at an Ochromonas biomass below 50 μg C L(-1), the grazing pressure on bacteria is low and with increasing Ochromonas biomass bacteria decline. Furthermore, in Lake Langau, a prominent deep chlorophyll maximum was found with chlorophyll concentrations ca. 50 times higher than in the epilimnion which was build up by the euglenophyte Lepocinclis sp. We conclude that lake morphometry, and specific abiotic characteristics such as mixing behaviour influence the community structure in these mining lakes.

  19. Storage capacity, detention time, and selected sediment deposition characteristics for Gull and Silver Lakes, Mono County, California

    USGS Publications Warehouse

    Blodgett, J.C.

    1996-01-01

    Bathymetric surveys made in September 1994 indicate the maximum storage capacity of Gull and Silver Lakes, California, is about 2,400 and 3,000 acre-feet, respectively. During March through October 1994, the lake level dropped 0.7 feet at both Gull Lake and Silver Lake. The associated change in storage was 60 acre-feet at Gull Lake and 80 acre-feet at Silver Lake. The flow detention time for average annual flow conditions at Gull Lake is about 2.5 years and for Silver Lake, the average detention time is about 19 days. Sediment deposition at the inlet to Silver Lake has been monitored since 1951 using aerial photography. During 1963 through 1994, the area of sediment deposition increased from 0.32 to about 2.4 acres. Analyses of these data indicate that the rate of deposition was lower during 1951-72 than the rate during 1973-94. Sediment deposition at the lake inlet is a continuing phenomenon.

  20. Inhibition of the alpha-ketoglutarate dehydrogenase complex by the myeloperoxidase products, hypochlorous acid and mono-N-chloramine.

    PubMed

    Jeitner, Thomas M; Xu, Hui; Gibson, Gary E

    2005-01-01

    Abstract alpha-Ketoglutarate dehydrogenase (KGDHC) complex activity is diminished in a number of neurodegenerative disorders and its diminution in Alzheimer Disease (AD) is thought to contribute to the major loss of cerebral energy metabolism that accompanies this disease. The loss of KGDHC activity appears to be predominantly due to post-translation modifications. Thiamine deficiency also results in decreased KGDHC activity and a selective neuronal loss. Recently, myeloperoxidase has been identified in the activated microglia of brains from AD patients and thiamine-deficient animals. Myeloperoxidase produces a powerful oxidant, hypochlorous acid that reacts with amines to form chloramines. The aim of this study was to investigate the ability of hypochlorous acid and chloramines to inhibit the activity of KGDHC activity as a first step towards investigating the role of myeloperoxidase in AD. Hypochlorous acid and mono-N-chloramine both inhibited purified and cellular KGDHC and the order of inhibition of the purified complex was hypochlorous acid (1x) > mono-N-chloramine (approximately 50x) > hydrogen peroxide (approximately 1,500). The inhibition of cellular KGDHC occurred with no significant loss of cellular viability at all exposure times that were examined. Thus, hypochlorous acid and chloramines have the potential to inactivate a major target in neurodegeneration.

  1. Microbial ecology of acid strip mine lakes in southern Indiana

    SciTech Connect

    Gyure, R.A.

    1986-01-01

    In this study, the author examined the limnology and microbial ecology of two acid strip mine lakes in the Greene-Sullivan State Forest near Dugger, Indiana. Reservoir 29 is a larger lake (225 ha) with water column pH of 2.7 and sediment pH of 3.8. Lake B, a smaller (20 ha) lake to the south of Reservoir 29, also has an acidic water column (pH 3.4) but more neutral sediments (pH 6.2). Both have very high sulfate concentrations: 20-30 mM in the water column and as high as 100 mM in the hypolimnion of Lake B. Low allochthonous carbon and nutrient input characterize these lakes as oligotrophic, although algal biomass is higher than would be expected for this trophic status. In both lakes, algal populations are not diverse, with a few species of single-celled Chlorophyta and euglenoids dominating. Algal biomass is concentrated in a thin 10 cm layer at the hypolimnion/metalimnion interface, although light intensity at this depth is low and severely limits productivity. Bacterial activity based on /sup 14/C-glucose incorporation is highest in the hypolimnion of both lakes, and sulfate-reduction is a dominant process in the sediments. Rates of sulfate-reduction compare with those in other freshwater environments, but are not as high as rates measured in high sulfate systems like saltmarsh and marine sediments.

  2. Influence of long-range atmospheric transportation (LRAT) on mono-to octa-chlorinated PCDD/Fs levels and distributions in soil around Qinghai Lake, China.

    PubMed

    Han, Ying; Liu, Wenbin; Hansen, Hans Chr Bruun; Chen, Xuebin; Liao, Xiao; Li, Haifeng; Wang, Mengjing; Yan, Nan

    2016-08-01

    Long-range atmospheric transportation (LRAT) of persistent organic pollutants followed by their deposition in cold, arid regions is of wide concern. This problem occurs at Qinghai Lake in the northeastern Tibetan Plateau, a sparsely populated area with extreme weather conditions and little current or historical anthropogenic pollution. The concentrations and distribution patterns of the mono-to octa-chlorinated dibenzo-p-dioxin and dibenzofuran (PCDD/F) congeners in surface soil samples collected from around Qinghai Lake were quantified. Concentration differences between low-(mono-to tri-) chlorinated PCDD/Fs and high-(tetra-to octa-) chlorinated PCDD/Fs were measured. High PCDD/F levels were detected, with total concentrations of 15,108 ± 6323 pg/g for the 27 PCDD/F congeners and 15,104 ± 6324 pg/g for the low-chlorinated PCDD/Fs. The concentrations of 17 2,3,7,8-substituted PCDD/Fs were only 3.1 ± 4.4 pg/g and the corresponding international toxicity equivalency (I-TEQ) was 0.11 ± 0.22 pg I-TEQ/g. Given their higher vapor pressures and lower boiling points, low-chlorinated PCDD/Fs, were predominantly gaseous, whereas high-chlorinated PCDD/Fs were predominantly solid, indicating that there is a higher potential for long-range transport of low-chlorinated PCDD/Fs. Overall, because of their high LRAT potential, low-chlorinated PCDD/Fs may pose a greater risk to local ecosystems in cold, remote areas than high-chlorinated PCDD/Fs.

  3. Spatial characterization of acid rain stress in Canadian Shield Lakes

    NASA Technical Reports Server (NTRS)

    Tanis, Fred J.

    1987-01-01

    The acidification of lake waters from airborne pollution is of continental proportions both in North America and Europe. A major concern of the acid rain problem is the cumulative ecosystem damage to lakes and forest. The number of lakes affected in northeastern U.S. and on the Canadian Shield is though to be enormous. How seasonal changes in lake transparency are related to annual acidic load was examined. The relationship between variations in lake acidification and ecophysical units was also examined. The utility of Thematic Mapper based observations to measure seasonal changes in the optical transparency in acid lakes was investigated. The potential for this optical response is related to a number of local ecophysical factors with bedrock geology being, perhaps, the most important. Other factors include sulfate deposition, vegetative cover, and terrain drainage/relief. The area of southern Ontario contains a wide variety of geologies from the most acid rain sensitive granite quartzite types to the least sensitive limestone dolomite sediments. Annual sulfate deposition ranges from 1.0 to 4.0 grams/sq m.

  4. Dynamics of the earth magnetic field in the 10-75 kyr period comprising the Laschamp and Mono Lake excursions: New results from the French Chaîne des Puys in a global perspective

    NASA Astrophysics Data System (ADS)

    Laj, Carlo; Guillou, Hervé; Kissel, Catherine

    2014-02-01

    We report here on a new paleomagnetic (directions and intensities) and coupled K/Ar and 40Ar/39Ar analysis of 35 different flows, emplaced in the Chaîne des Puys during the 75 to 10 kyr interval, which contains the Mono Lake and Laschamp excursions. There is a remarkable agreement between the new set of absolute volcanic intensities and published sedimentary (GLOPIS-75) and cosmogenic (10Be and 36Cl) records. The Laschamp and Mono Lake excursions are clearly revealed by a very significant intensity drop at 41.2±1.6 ka and 34.2±1.2 ka respectively. The duration of the Laschamp excursion is ˜1500 yr and about 640 yr when the drop of paleointensity or the directional change are considered respectively. The intensity drop at the Mono Lake is twice as short. In the ˜7 ka interval separating the two excursions, the field intensity recovers to almost non-transitional values. The rate of decrease of the field intensity during these excursions attains 18 nT/yr for the Laschamp and even greater value (33 nT/yr) for the Mono Lake. This figure is, for the Laschamp excursion, similar to the present field intensity decrease in the last two centuries so that one may wonder whether such a high rate of change may be characteristic of an impending geomagnetic event (reversal or excursion). We suggest that the name Auckland excursion should be used for the present-day called Mono Lake.

  5. Climate Change Impacts on the Los Angeles Aqueducts Water Sources: 21st Century Hydrologic Projections for Owens Valley and Mono Lake Watershed

    NASA Astrophysics Data System (ADS)

    Costa-Cabral, M. C.; Roy, S. B.; Maurer, E. P.; Mills, W. B.; Chen, L.

    2011-12-01

    Precipitation from the Eastern Sierra Nevada watersheds of Owens Lake and Mono Lake is one of the main water sources, and the one of highest quality, for Los Angeles' more than 4 million people. Winter snow is stored in the large snowpack reservoir, and meltwater (~0.2-0.5 million acre-feet) is delivered annually to the city in the dry season by the 340-mile long Los Angeles Aqueduct system, operated by the Los Angeles Department of Water and Power. We identify plausible scenarios of future climate conditions in the Owens-Mono watersheds over the 21st century based on CMIP3 results for 16 global climate models (GCMs) statistically downscaled to 1/8° and greenhouse gas emission scenarios A2 and B1; and we evaluate the consequent hydrologic impacts using the Variable Infiltration Capacity (VIC) hydrologic model. Such climate scenarios have large and unquantifiable associated uncertainty and do not represent predictions, but are considered to be plausible under the current state of knowledge. We applied VIC to the Owens-Mono watersheds and calibrated the model using monthly streamflow records provided by LADWP. Of most interest to Los Angeles' water supply are the projections for the snowpack and the dry-season hydrograph that relies on snowmelt. Our results indicate future increases in the fraction of precipitation falling as rain rather than snow, from a historical value of about 20% to 20-30% by mid-century and 28-52% by end of century (depending on the GCM) for scenario A2. As a result, the snowpack's peak snow water equivalent (SWE) is projected to decline by most GCMs. The SWE peak is also projected to shift toward earlier dates (by a few days by mid-century and by a GCM-average of 2 weeks by end of century under emissions scenario A2). The diminished SWE, earlier SWE peak and earlier melt associated with rising temperatures result in earlier hydrograph peaks, a shift in the date marking the passage of half of the year's hydrograph volume (by more than one

  6. Extremely acid Permian lakes and ground waters in North America

    USGS Publications Warehouse

    Benison, K.C.; Goldstein, R.H.; Wopenka, B.; Burruss, R.C.; Pasteris, J.D.

    1998-01-01

    Evaporites hosted by red beds (red shales and sandstones), some 275-265 million years old, extend over a large area of the North American mid- continent. They were deposited in non-marine saline lakes, pans and mud- flats, settings that are typically assumed to have been alkaline. Here we use laser Raman microprobe analyses of fluid inclusions trapped in halites from these Permian deposits to argue for the existence of highly acidic (pH < 1) lakes and ground waters. These extremely acidic systems may have extended over an area of 200,000 km2. Modern analogues of such systems may be natural acid lake and groundwater systems (pH ~2-4) in southern Australia. Both the ancient and modern acid systems are characterized by closed drainage, arid climate, low acid-neutralizing capacity, and the oxidation of minerals such as pyrite to generate acidity. The discovery of widespread ancient acid lake and groundwater systems demands a re-evaluation of reconstructions of surface conditions of the past, and further investigations of the geochemistry and ecology of acid systems in general.

  7. Similar bacterial community composition in acidic mining lakes with different pH and lake chemistry.

    PubMed

    Kampe, Heike; Dziallas, Claudia; Grossart, Hans-Peter; Kamjunke, Norbert

    2010-10-01

    As extreme environmental conditions strongly affect bacterial community composition (BCC), we examined whether differences in pH-even at low pH-and in iron and sulfate concentrations lead to changes in BCC of acidic mining lakes. Thereby, we tested the following hypotheses: (1) diversity of the bacterial community in acidic lakes decreases with reducing pH, (2) BCC differs between epilimnion and hypolimnion, and (3) BCC in extremely acidic environments does not vary much over time. Therefore, we investigated the BCC of three acidic lakes with different pH values (2.3, 2.7, and 3.2) by denaturing gradient gel electrophoresis (DGGE) and subsequent sequencing of DGGE bands as well as catalyzed reporter deposition-FISH (CARD-FISH). BCC did not significantly vary among the studied lakes nor differ much between water layers. In contrast, BCC significantly changed over time, which is contradictory to our hypotheses. Bacterial communities were dominated by Alpha-, Beta-, and Gammaproteobacteria, whereas Actino- and Acidobacteria rarely occurred. Cell numbers of both free and attached bacteria were positively related to DOC concentration. Overall, low pH and extreme chemical conditions of the studied lakes led to similar assemblages of bacteria with pronounced temporal differences. This notion indicates that temporal changes in environmental conditions including food web structure also affect unique communities of bacteria thriving at low pH.

  8. Investigation of mono/competitive adsorption of environmentally relevant ionized weak acids on graphite: impact of molecular properties and thermodynamics.

    PubMed

    Moustafa, Ahmed M A; McPhedran, Kerry N; Moreira, Jesús; Gamal El-Din, Mohamed

    2014-12-16

    The thermodynamics of adsorption and competitive interactions of five weak acids on a graphite surface was assessed in alkaline solutions. Adsorption of the acids in mono- and multicompound solutions followed their Freundlich isotherms which suggest a diversity of graphite adsorption sites as confirmed by the presence of carboxylic and phenolic groups observed on graphite surfaces. Thermodynamic calculations assigned the formation of the negatively charged assisted hydrogen bond (-CAHB) between ionized solutes and adsorbent surface groups as the possible adsorption mechanism. However, the similar pKa values of current acids resulted in comparable free energies for -CAHB formation (ΔG(-CAHB)) being less than solvation free energies (ΔGSolv). Thus, additional ΔG is supplemented by increased hydrophobicity due to proton exchange of ionized acids with water (ΔΔG Hydrophobicity). Adsorption capacities and competition coefficients indicated that ΔΔG Hydrophobicity values depend on the neutral and ionized acid Kow. Competitive adsorption implies that multilayer adsorption may occur via hydrophobic bonding with the CH3 ends of the self-assembled layer which affects the acid adsorption capacities in mixtures as compared to monocompound solutions. The determination of adsorption mechanisms will assist in understanding of the fate and bioavailability of emerging and classical weak acids released into natural waters.

  9. Mono County geothermal activity

    SciTech Connect

    Lyster, D.L.

    1986-01-01

    Three geothermal projects have been proposed or are underway in Mono County, California. The Mammoth/Chance geothermal development project plans to construct a 10-MW geothermal binary power plant which will include 8 production and 3 injection wells. Pacific Lighting Energy Systems is also planning a 10-MW binary power plant consisting of 5 geothermal wells and up to 4 injection wells. A geothermal research project near Mammoth Lakes has spudded a well to provide a way to periodically measure temperature gradient, pressure, and chemistry of the thermal waters and to investigate the space-heating potential of the area in the vicinity of Mammoth Lakes. All three projects are briefly described.

  10. Microbial Sulfur Cycling in an Acid Mine Lake

    NASA Astrophysics Data System (ADS)

    Bernier, L.; Warren, L. A.

    2004-12-01

    Geochemical dynamics of a tailings impacted lake in Northern Ontario were investigated over a three-year period, in which active pyrrhotite slurry disposal was initiated in year two. A strong seasonal trend of decreasing epilimnetic pH with significant diurnal acid production, pre-, during and post slurry deposition was observed with high rates observed compared to pre-slurry. Slurry deposition occurred at the surface of the lake and acted as a reaction stimulant for acid generation. Over the diurnal timescale investigated, the highest rates of acid production occurred not at the lake surface but within the metaliminetic region of the lake. This region was exemplified by strong decreasing oxygen gradients, and thus observed high rates of acid generation are more consistent with microbial pathways of sulfur oxidation than with abiotic, oxygen catalyzed pathways. Consistent with microbial catalysis, metalimnetic rates of acid generation were highest during June and July when microbial populations and metabolic rates were maximal. These results indicate that microbial oxidation of sulfur species play a major role in acid generation in this system. Further, observed rates of acid generation exceed those predicted by published abiotic rates of pyrrhotite oxidation, but are consistent with literature estimates of acid generation catalyzed by microbial activity. Acidithiobacilli accounted for up to 50% of the microbial community pre slurry, but were absent post slurry deposition. These results are the first to demonstrate quantitatively that microbial sulfur oxidation can play a predominant role in acid generation within mine tailings impacted systems. They further highlight the need to evaluate the more complex pathways by which microorganisms process sulfur as the conditions, controls and process rates differ from those observed for abiotic reactions.

  11. Effect of Butanedioic Acid Mono (2,2-Dimethylhydrazide) on the Activity of Membrane-Bound Succinate Dehydrogenase

    PubMed Central

    See, Raymond M.; Foy, Chester L.

    1982-01-01

    Mitochondria isolated from hypocotyls of five-day-old bean (Phaseolus vulgaris L. `Black Valentine') seedlings rapidly oxidized succinate, malate, and NADH. Oxidation rates, respiratory control, and ADP:O ratios obtained with saturating concentrations of all three substrates indicated that the mitochondria were tightly coupled. The mitochondrial preparation was then employed to investigate the respiration-inhibiting effects of butanedioic acid mono (2,2-dimethyl-hydrazide) (daminozide) a plant growth retardant having structural similarity to an endogenous respiratory substrate (succinate). Daminozide markedly inhibited the activity of membrane-bound succinate dehydrogenase. Inhibition was of the competitive type (apparent Ki, 20.2 millimolar) with respect to succinate. Although not excluding other hypotheses, the results support an active role for daminozide in the suppression of respiration as an important metabolic site of its action as a plant growth regulator. PMID:16662493

  12. Thiamine and fatty acid content of Lake Michigan Chinook salmon

    USGS Publications Warehouse

    Honeyfield, D.C.; Peters, A.K.; Jones, M.L.

    2008-01-01

    Nutritional status of Lake Michigan Chinook salmon (Oncorhynchus tshawytscha) is inadequately documented. An investigation was conducted to determine muscle and liver thiamine content and whole body fatty acid composition in small, medium and large Chinook salmon. Muscle and liver thiamine concentrations were highest in small salmon, and tended to decrease with increasing fish size. Muscle thiamine was higher in fall than spring in large salmon. The high percentage of Chinook salmon (24-32% in fall and 58-71% in spring) with muscle thiamine concentration below 500 pmol/g, which has been associated with loss of equilibrium and death in other Great Lake salmonines, suggest that Chinook appear to rely less on thiamine than other Great Lakes species for which such low concentrations would be associated with thiamine deficiency (Brown et al. 2005b). A positive correlation was observed between liver total thiamine and percent liver lipids (r = 0.53, P < 0.0001, n = 119). In medium and large salmon, liver lipids were observed to be low in fish with less than 4,000 pmol/g liver total thiamine. In individuals with greater than 4,000 pmol/g liver thiamine, liver lipid increased with thiamine concentration. Individual fatty acids declined between fall and spring. Essential omega-3 fatty acids appear to be conserved as lipid content declined. Arachidonic acid (C20:4n6), an essential omega-6 fatty acid was not different between fall and spring, although the sum of omega-6 (Sw6) fatty acids declined over winter. Elevated concentrations of saturated fatty acids (sum) were observed in whole body tissue lipid. In summary, thiamine, a dietary essential vitamin, and individual fatty acids were found to vary in Lake Michigan Chinook salmon by fish size and season of the year.

  13. Enrichment and isolation of Bacillus beveridgei sp. nov., a facultative anaerobic haloalkaliphile from Mono Lake, California, that respires oxyanions of tellurium, selenium, and arsenic

    USGS Publications Warehouse

    Baesman, S.M.; Stolz, J.F.; Kulp, T.R.; Oremland, R.S.

    2009-01-01

    Mono Lake sediment slurries incubated with lactate and tellurite [Te(IV)] turned progressively black with time because of the precipitation of elemental tellurium [Te(0)]. An enrichment culture was established from these slurries that demonstrated Te(IV)-dependent growth. The enrichment was purified by picking isolated black colonies from lactate/Te(IV) agar plates, followed by repeated streaking and picking. The isolate, strain MLTeJB, grew in aqueous Te(IV)-medium if provided with a small amount of sterile solid phase material (e.g., agar plug; glass beads). Strain MLTeJB grew at high concentrations of Te(IV) (~8 mM) by oxidizing lactate to acetate plus formate, while reducing Te(IV) to Te(0). Other electron acceptors that were found to sustain growth were tellurate, selenate, selenite, arsenate, nitrate, nitrite, fumarate and oxygen. Notably, growth on arsenate, nitrate, nitrite and fumarate did not result in the accumulation of formate, implying that in these cases lactate was oxidized to acetate plus CO2. Strain MLTeJB is a low G + C Gram positive motile rod with pH, sodium, and temperature growth optima at 8.5-9.0, 0.5-1.5 M, and 40??C, respectively. The epithet Bacillus beveridgei strain MLTeJBT is proposed. ?? 2009 Springer.

  14. Bacillus arsenicoselenatis, sp. nov., and Bacillus selenitireducens, sp. nov.: Two haloalkaliphiles from Mono Lake, California that respire oxyanions of selenium and arsenic

    USGS Publications Warehouse

    Switzer, Blum J.; Burns, Bindi A.; Buzzelli, J.; Stolz, J.F.; Oremland, R.S.

    1998-01-01

    Two gram-positive anaerobic bacteria (strains E1H and MLS10) were isolated from the anoxic muds of Mono Lake, California, an alkaline, hypersaline, arsenic-rich water body. Both grew by dissimilatory reduction of As(V) to As(III) with the concomitant oxidation of lactate to acetate plus CO2. Bacillus arsenicoselenatis (strain E1H) is a spore-forming rod that also grew by dissimilatory reduction of Se(VI) to Se(IV). Bacillus selenitireducens (strain MLS 10) is a short, non-spore-forming rod that grew by dissimilatory reduction of Se(IV) to Se(0). When the two isolates were cocultured, a complete reduction of Se(VI) to Se(0) was achieved. Both isolates are alkaliphiles and had optimal specific growth rates in the pH range of 8.5-10. Strain E1H had a salinity optimum at 60 g 1-1 NaCl, while strain MLS10 had optimal growth at lower salinities (24-60 g 1-1 NaCl). Both strains have limited abilities to grow with electron donors and acceptors other than those given above. Strain MLS10 demonstrated weak growth as a microaerophile and was also capable of fermentative growth on glucose, while strain E1H is a strict anaerobe. Comparative 16S rRNA gene sequence analysis placed the two isolates with other Bacillus spp. in the low G+C gram-positive group of bacteria.

  15. Analysis of ammonia-oxidizing bacteria from hypersaline Mono Lake, California, on the basis of 16S rRNA sequences.

    PubMed

    Ward, B B; Martino, D P; Diaz, M C; Joye, S B

    2000-07-01

    Ammonia-oxidizing bacteria were detected by PCR amplification of DNA extracted from filtered water samples throughout the water column of Mono Lake, California. Ammonia-oxidizing members of the beta subdivision of the division Proteobacteria (beta-subdivision Proteobacteria) were detected using previously characterized PCR primers; target sequences were detected by direct amplification in both surface water and below the chemocline. Denaturing gradient gel electrophoresis analysis indicated the presence of at least four different beta-subdivision ammonia oxidizers in some samples. Subsequent sequencing of amplified 16S rDNA fragments verified the presence of sequences very similar to those of cultured Nitrosomonas strains. Two separate analyses, carried out under different conditions (different reagents, locations, PCR machines, sequencers, etc.), 2 years apart, detected similar ranges of sequence diversity in these samples. It seems likely that the physiological diversity of nitrifiers exceeds the diversity of their ribosomal sequences and that these sequences represent members of the Nitrosomonas europaea group that are acclimated to alkaline, high-salinity environments. Primers specific for Nitrosococcus oceanus, a marine ammonia-oxidizing bacterium in the gamma subdivision of the Proteobacteria, did not amplify target from any samples.

  16. Enrichment and isolation of Bacillus beveridgei sp. nov., a facultative anaerobic haloalkaliphile from Mono Lake, California, that respires oxyanions of tellurium, selenium, and arsenic.

    PubMed

    Baesman, S M; Stolz, J F; Kulp, T R; Oremland, Ronald S

    2009-07-01

    Mono Lake sediment slurries incubated with lactate and tellurite [Te(IV)] turned progressively black with time because of the precipitation of elemental tellurium [Te(0)]. An enrichment culture was established from these slurries that demonstrated Te(IV)-dependent growth. The enrichment was purified by picking isolated black colonies from lactate/Te(IV) agar plates, followed by repeated streaking and picking. The isolate, strain MLTeJB, grew in aqueous Te(IV)-medium if provided with a small amount of sterile solid phase material (e.g., agar plug; glass beads). Strain MLTeJB grew at high concentrations of Te(IV) (~8 mM) by oxidizing lactate to acetate plus formate, while reducing Te(IV) to Te(0). Other electron acceptors that were found to sustain growth were tellurate, selenate, selenite, arsenate, nitrate, nitrite, fumarate and oxygen. Notably, growth on arsenate, nitrate, nitrite and fumarate did not result in the accumulation of formate, implying that in these cases lactate was oxidized to acetate plus CO(2). Strain MLTeJB is a low G + C Gram positive motile rod with pH, sodium, and temperature growth optima at 8.5-9.0, 0.5-1.5 M, and 40 degrees C, respectively. The epithet Bacillus beveridgei strain MLTeJB(T) is proposed.

  17. Bacillus arsenicoselenatis, sp. nov., and Bacillus selenitireducens, sp. nov.: two haloalkaliphiles from Mono Lake, California that respire oxyanions of selenium and arsenic.

    PubMed

    Switzer Blum, J; Burns Bindi, A; Buzzelli, J; Stolz, J F; Oremland, R S

    1998-12-01

    Two gram-positive anaerobic bacteria (strains E1H and MLS10) were isolated from the anoxic muds of Mono Lake, California, an alkaline, hypersaline, arsenic-rich water body. Both grew by dissimilatory reduction of As(V) to As(III) with the concomitant oxidation of lactate to acetate plus CO2. Bacillus arsenicoselenatis (strain E1H) is a spore-forming rod that also grew by dissimilatory reduction of Se(VI) to Se(IV). Bacillus selenitireducens (strain MLS10) is a short, non-spore-forming rod that grew by dissimilatory reduction of Se(IV) to Se(0). When the two isolates were cocultured, a complete reduction of Se(VI) to Se(0) was achieved. Both isolates are alkaliphiles and had optimal specific growth rates in the pH range of 8.5-10. Strain E1H had a salinity optimum at 60 g l-1 NaCl, while strain MLS10 had optimal growth at lower salinities (24-60 g l-1 NaCl). Both strains have limited abilities to grow with electron donors and acceptors other than those given above. Strain MLS10 demonstrated weak growth as a microaerophile and was also capable of fermentative growth on glucose, while strain E1H is a strict anaerobe. Comparative 16S rRNA gene sequence analysis placed the two isolates with other Bacillus spp. in the low G+C gram-positive group of bacteria.

  18. Mono County update

    SciTech Connect

    Lyster, D.L.

    1987-07-01

    In May 1987, the Mono County Energy Management Department recommended that a two-year moratorium be placed on geothermal power production projects on private lands within the Mono-Long Valley KGRA. The intent of the proposed moratorium was to allow for the collection and evaluation of hydrologic monitoring data in the Long Valley Caldera. Now, to still achieve this end, the Energy Management Department will suggest that mitigation measures and project-specific monitoring requirements be implemented via the California Environmental Quality Act (CEQA) documentation and the county use permit process. The monitoring data will provide important information to Mono County decision-makers regarding potential adverse impacts from geothermal production on such local resources as Hot Creek Gorge, the Hot Creek Fish Hatchery, and Hot Creek, itself. The Mammoth/Chance Geothermal Project is the proposed construction and operation of a 10 megawatt, net, geothermal binary-cycle power plant and production- and injection-well field by Bonneville Pacific Corporation. The project is currently under environmental review, pursuant to CEQA requirements. The Mono County Energy Management Director is providing assistance to the Town of Mammoth Lakes on its California Energy Commission (CEC) grant-funded resource assessment project. The grant of $220,000 provides for the drilling of at least two temperature-gradient wells (exploratory wells) within the town limits. If a geothermal resource is detected and found to provide adequate flows at a suitable temperature, the Town of Mammoth Lakes will proceed in the development of a geothermal space-heating system to provide heat to such users as the Centinela Mammoth Hospital, Mammoth elementary and high schools, the Gateway Industrial Park, and future residential development projects.

  19. Mono Test

    MedlinePlus

    ... services. Advertising & Sponsorship: Policy | Opportunities PLEASE NOTE: Your web browser does not have JavaScript enabled. Unless you enable Javascript , your ability to navigate and access the features of this website will be ... Mononucleosis (Mono) Test Share this page: Was this page helpful? Also ...

  20. Spatial and spectral characterization of acid rain stress in Canadian Shield lakes

    NASA Technical Reports Server (NTRS)

    Marshall, Elizabeth J.; Tanis, Frederick J.

    1989-01-01

    Results from this study demonstrate that a remote sensor can discriminate lake clarity based upon reflection. The basic hypothesis was that seasonal and multiyear changes in lake optical transparency are indicative of sensitivity to acidic deposition. In many acid-sensitive lakes optical transparency is controlled by the amount of dissolved organic carbon (DOC) present. DOC is a strong absorbing, nonscattering material which has the greatest impact at short visible wavelengths, including Thematic Mapper band 1. Acid-sensitive lakes have high concentrations of aluminum which have been mobilized by acidic components contained in the runoff. Aluminum complexing with DOC is considered to be the primary mechanism to account for observed increases in lake transparency in acid-sensitive lakes. Thus seasonal changes in the optical transparency of lakes should provide an indication of the stress due to acid deposition and loading.

  1. Assessment of lake sensitivity to acidic deposition in national parks of the Rocky Mountains

    USGS Publications Warehouse

    Nanus, L.; Williams, M.W.; Campbell, D.H.; Tonnessen, K.A.; Blett, T.; Clow, D.W.

    2009-01-01

    The sensitivity of high-elevation lakes to acidic deposition was evaluated in five national parks of the Rocky Mountains based on statistical relations between lake acid-neutralizing capacity concentrations and basin characteristics. Acid-neutralizing capacity (ANC) of 151 lakes sampled during synoptic surveys and basin-characteristic information derived from geographic information system (GIS) data sets were used to calibrate the statistical models. The explanatory basin variables that were considered included topographic parameters, bedrock type, and vegetation type. A logistic regression model was developed, and modeling results were cross-validated through lake sampling during fall 2004 at 58 lakes. The model was applied to lake basins greater than 1 ha in area in Glacier National Park (n = 244 lakes), Grand Teton National Park (n = 106 lakes), Great Sand Dunes National Park and Preserve (n = 11 lakes), Rocky Mountain National Park (n = 114 lakes), and Yellowstone National Park (n = 294 lakes). Lakes that had a high probability of having an ANC concentration 3000 m, with 80% of the catchment bedrock having low buffering capacity. The modeling results indicate that the most sensitive lakes are located in Rocky Mountain National Park and Grand Teton National Park. This technique for evaluating the lake sensitivity to acidic deposition is useful for designing long-term monitoring plans and is potentially transferable to other remote mountain areas of the United States and the world.

  2. Decomposition of Alternative Chirality Amino Acids by Alkaliphilic Anaerobe from Owens Lake, California

    NASA Technical Reports Server (NTRS)

    Townsend, Alisa; Pikuta, Elena V.; Guisler, Melissa; Hoover, Richard B.

    2009-01-01

    The study of alkaliphilic microbial communities from anaerobic sediments of Owens and Mono Lakes in California led to the isolation of a bacterial strain capable of metabolizing amino acids with alternative chirality. According to the phylogenetic analysis, the anaerobic strain BK1 belongs to the genus Tindallia; however, despite the characteristics of other described species of this genus, the strain BK1 was able to grow on D-arginine and Dlysine. Cell morphology of this strain showed straight, motile, non-spore-forming rods with sizes 0.45 x 1.2-3 microns. Physiological characteristics of the strain showed that it is catalase negative, obligately anaerobic, mesophilic, and obligately alkaliphilic. This isolate is unable to grow at pH 7 and requires CO3 (2-) ions for growth. The strain has chemo-heterotrophic metabolism and is able to ferment various proteolysis products and some sugars. It plays the role of a primary anaerobe within the trophic chain of an anaerobic microbial community by the degradation of complex protein molecules to smaller and less energetic molecules. The new isolate requires NaCl for growth, and can grow within the range of 0.5-13 %, with the optimum at 1 % NaCl (w/v). The temperature range for the growth of the new isolate is 12-40 C with optimum at 35 C. The pH range for the growth of strain BK1 occurs between 7.8 and 11.0 with optimum at 9.5. This paper presents detailed physiological characteristics of the novel isolate from Owens Lake, a unique relic ecosystem of Astrobiological significance, and makes an accent on the ability of this strain to utilize L-amino acids.

  3. Analysis of acylglycerols containing mono- and dihydroxy fatty acids in castor oil by HPLC and MS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ricinoleate, a monohydroxy fatty acid, has many industrial uses such as the manufacture of aviation lubricant, plastic, paint and cosmetics. Ricinoleate occurs as acylglycerols (AG) in castor oil, and about 70% of castor oil is triricinolein. Castor oil is the only commercial source of ricinoleate. ...

  4. Preliminary Paleomagnetic Data From Santa Mariá Volcano, Guatemala and Their Bearing on the Mono Lake and Hilina Pali Excursions

    NASA Astrophysics Data System (ADS)

    Escobar Wolf, R. P.; Diehl, J. F.; Rose, W. I.; Singer, B. S.

    2005-12-01

    Paleomagnetic directions determined from oriented block samples collected by Rose et al. in 1977 ( Journal of Geology) and from eight paleomagnetic sites drilled in lava flows from Santa Maria volcano, Guatemala in 1990 define a pattern of variation similar to the pattern of geomagnetic field changes recorded by the sediments of the Wilson Creek Formation near Mono Lake, California. This led Conway et al. in 1994 ( Journal of Geology) to suggest that these flows had recorded the Mono Lake Excursion (MLE). The correlation was made on pattern recognition alone and relied almost entirely the well- defined inclination dataset than on the declination data; no radioisotopic ages were available. In March of 2005 we returned to the crater of Santa Mariá and drilled 23 lava flows from the original sections of Rose et al; block samples for 40Ar/39Ar were also collected. Unfortunately aggradation in the crater due to mass wasting made it impossible to sample all the flows of Rose et al. At each site or lava flow, four to seven cores were drilled and oriented with a sun compass. Samples cut from the drilled cores were magnetically cleaned using alternation field demagnetization and analyzed using principle component analysis. Thermal demagnetization is currently underway. The resulting inclination waveform (over 70° of change from +60° to -12°) is very similar to those previously reported in the literature for the MLE, but the declination waveform shows little variation (<25°; mean declination is 13.4°) throughout the stratigraphic sequence that we collected. Consequently, VGP data from the lava flows do not show the classic clockwise and counterclockwise loops as seen at the Wilson Creek section and at other MLE locations. Instead the directions (VGPs) tend to cluster in three distinct groups with the lowermost lava flows (5) and uppermost lava flows (3) clustering near the expected axial dipole inclination for the region (~28 °) while lava flows from the middle of the

  5. Determination of mono- and dichloroacetic acids in betaine media by liquid chromatography.

    PubMed

    Ghassempour, Alireza; Chalavi, Soheila; Abdollahpour, Assem; Mirkhani, Seyed Amir

    2006-02-15

    A simple and sensitive method has been developed for the analysis of residue amounts of chloroacetic acids in betaine samples based on derivatization by 1-naphthylamine (NA). The derivatized compounds are analyzed by reverse phase high performance liquid chromatography using methanol and water as mobile phase in the ratio of 32/68 (v/v) and phenyl column and PDA detection at 222nm. The detection limits (LOD) of monochloroacetic acid (MCA) and dichloroacetic acid (DCA) are 0.1 and 0.15mugmL(-1), respectively. The limits of quantification (LOQ) and the linear dynamic ranges (LDR) of MCA are found to be 1 and 1-400mugmL(-1), respectively, and for DCA are found to be 3 and 3-400mugmL(-1), respectively. The precision at the 5ppm level for MCA and DCA are about 3% and 2%, (n=5), respectively. The average recovery for MCA and DCA spiked to betaine samples are 98% and 97%, respectively.

  6. Dietary palmitic acid influences LDL-mediated lymphocyte proliferation differently to other mono- and polyunsaturated fatty acids in rats.

    PubMed

    Tinahones, F J; Gómez-Zumaquero, J M; Monzón, A; Rojo-Martínez, G; Pareja, A; Morcillo, S; Cardona, F; Olveira, G; Soriguer, F

    2004-10-01

    Recent studies suggest that the biological effects of saturated fatty acids depend on the length of their chain. We compared the effect of diets containing different fatty acids on plasma lipids and lymphocyte proliferation in the presence of lovastatin and with increasing amounts of LDL. Lymphocytes from rats fed with a diet rich in palmitic acid had a greater lymphocyte proliferation capacity than those from rats fed with diets rich in oleic acid, linoleic acid, or fish oil. This effect was maintained when small amounts of polyunsaturatwed fatty acids (PUFA; sunflower oil) were added to the palmitic acid diet. LDL receptor activity, measured by the capacity of lovastatin to revert the inhibition of lymphocyte proliferation with increasing amounts of LDL in the medium, was greater in the rats fed with palmitic acid, and was similar to the other groups when small amounts of PUFA were added. All the groups had similar levels of plasma cholesterol, but the LDL levels were significantly lower in the group fed with palmitic acid plus PUFA. The highest HDL-cholesterol (HDLc) levels were found in the palmitic acid group and the lowest LDL-cholesterol (LDLc)/HDLc ratio in the palmitic acid plus PUFA group. These results suggest that diets rich in palmitic acid do not raise total cholesterol, but reduce LDLc or keep it normal, and raise HDLc levels. This effect may be partly due to an increase in LDL receptor activity. The inclusion of small amounts of PUFA in the diet rich in palmitic acid substantially modified the LDL receptor response in the lymphocytes, suggesting that the proportion of different families of dietary fatty acids may be more important than the individual amount of each in absolute terms to explain their effects on plasma lipids and lipoproteins.

  7. Acid lake in N.Y. gets relief

    NASA Astrophysics Data System (ADS)

    A pond in the Adirondack Mountains of New York State has received a second soothing dose of baking soda. The 21 tons of sodium bicarbonate should moderate the pond's acidic conditions, lethal to fish and other forms of life.Wolf Pond, 25 miles (40 km) north of Saranac Lake, has developed an extremely low pH (4.5) because of acid rain and the runoff of acidic surface water, combined with very little outflow. The pond was first treated with sodium bicarbonate by t h e New York Department of Environmental Conservation in 1984; afterward the pH rose to about 6.2. Fish stocked by local residents have continued to live in the pond, despite the eventual rebound in its acidity.

  8. Enzymatic production of enantiopure amino acids from mono-substituted hydantoin substrates.

    PubMed

    Matcher, Gwynneth F; Dorrington, Rosemary A; Burton, Stephanie G

    2012-01-01

    Biocatalytic conversion of 5-substituted hydantoin derivatives is an efficient method for the production of unnatural enantiomerically pure amino acids. The enzymes required to carry out this hydrolysis occur in a wide variety of eubacterial species each of which exhibit variations in substrate selectivity, enantiospecificity, and catalytic efficiency. Screening of the natural environment for bacterial strains capable of utilizing hydantoin as a nutrient source (as opposed to rational protein design of known enzymes) is a cost-effective and valuable approach for isolating microbial species with novel hydantoin-hydrolysing enzyme systems. Once candidate microbial isolates have been identified, characterization and optimization of the activity of target enzyme systems can be achieved by subjecting the hydantoin-hydrolysing system to physicochemical manipulations aimed at the enzymes activity within the natural host cells, expressed in a heterologous host, or as purified enzymes. The latter two options require knowledge of the genes encoding for the hydantoin-hydrolysing enzymes. This chapter describes the methods that can be used in conducting such development of hydantoinase-based biocatalytic routes for production of target amino acids.

  9. Synthesis and evaluation of quinazoline amino acid derivatives as mono amine oxidase (MAO) inhibitors.

    PubMed

    Khattab, Sherine Nabil; Haiba, Nesreen Saied; Asal, Ahmed Mosaad; Bekhit, Adnan A; Amer, Adel; Abdel-Rahman, Hamdy M; El-Faham, Ayman

    2015-07-01

    A series of quinazolinone amino acid ester and quinazolinone amino acid hydrazides were prepared under microwave irradiation as well as conventional condition. The microwave irradiation afforded the product in less reaction time, higher yield and purity. The structures of the synthesized compounds were confirmed by IR, NMR, and elemental analysis. The new synthesized compounds were studied for their monoamine oxidase inhibitory activity. They showed more selective inhibitory activity toward MAO-A than MAO-B. Compounds 7, 10, and 15 showed MAO-A inhibition activity (IC50=3.6×10(-9), 2.8×10(-9), 2.1×10(-9) M, respectively) comparable to that of the standard clorgyline (IC50=2.9×10(-9)M). 2-(2-(Benzo[d][1,3]dioxol-5-yl)-4-oxo-1,2-dihydroquinazolin-3(4H)-yl)acetohydrazide 15 showed selective MAO-A inhibition activity (SI=39524) superior to that of the standard clorgyline (SI=33793). The acute toxicity of the synthesized compounds was determined. In addition, computer-assisted simulated docking experiments were performed to rationalize the biological activity.

  10. Australian Acid Brine Lake as a Mars Analog: An Analysis of Preserved Lipids in Shore and Lake Sediments

    NASA Astrophysics Data System (ADS)

    Graham, H. V.; Stern, J. C.; Baldridge, A. M.; Thomsen, B. J.

    2016-05-01

    This study investigates organic molecules preserved in sediment cores from an acid brine lake. We explore the distribution and stable isotopic composition of lipids in order to understand preservation potential in similar martian environments.

  11. Plasma osmotic and electrolyte concentrations of largemouth bass from some acidic Florida lakes

    SciTech Connect

    Canfield, D.E. Jr.; Maceina, M.J.; Nordlie, F.G.; Shireman, J.V.

    1985-05-01

    Five acidic clear (pH 3.7-4.9), three acidic colored (pH 4.1-4.6), and three neutral (pH 6.9-7.3) north-central Florida lakes were surveyed in 1983 to determine plasma osmotic and electrolyte concentrations, growth, and coefficients of condition for largemouth bass Micropterus salmoides floridanus. Plasma osmotic concentrations averaged greater than 273 milliosmoles/kg in fish from acidic colored and circumneutral lakes, but averaged less than 269 milliosmoles/kg in four of the acidic clear lakes. Growth and coefficients of condition of largemouth bass > 305 mm total length in the acidic lakes were significantly lower than in the neutral lakes. Reductions in fish growth and condition, however, could be related to either acidic conditions or lake trophic status. 29 references, 3 tables.

  12. Investigation of acyl migration in mono- and dicaffeoylquinic acids under aqueous basic, aqueous acidic, and dry roasting conditions.

    PubMed

    Deshpande, Sagar; Jaiswal, Rakesh; Matei, Marius Febi; Kuhnert, Nikolai

    2014-09-17

    Acyl migration in chlorogenic acids describes the process of migration of cinnamoyl moieties from one quinic acid alcohol group to another, thus interconverting chlorogenic acid regioisomers. It therefore constitutes a special case of transesterification reaction. Acyl migration constitutes an important reaction pathway in both coffee roasting and brewing, altering the structure of chlorogenic acid initially present in the green coffee bean. In this contribution we describe detailed and comprehensive mechanistic studies comparing inter- and intramolecular acyl migration involving the seven most common chlorogenic acids in coffee. We employe aqueous acidic and basic conditions mimicking the brewing of coffee along with dry roasting conditions. We show that under aqueous basic conditions intramolecular acyl migration is fully reversible with basic hydrolysis competing with acyl migration. 3-Caffeoylquinic acid was shown to be most labile to basic hydrolysis. We additionally show that the acyl migration process is strongly pH dependent with increased transesterification taking place at basic pH. Under dry roasting conditions acyl migration competes with dehydration to form lactones. We argue that acyl migration precedes lactonization, with 3-caffeoylquinic acid lactone being the predominant product.

  13. Metals in crayfish from neutralized acidic and non-acidic lakes

    SciTech Connect

    Bagatto, G.; Alikhan, M.A.

    1987-09-01

    Large amounts of acid forming SO/sub 2/, as well as Cu, Ni and other metals are being continuously released into the environment by mining and smelting activities at Sudbury, Ontario, Canada. Consequently, a number of lakes in this region has become both acid and metal stressed. The addition of basic calcium compounds to acidic ponds and lakes has long been recognized as beneficial, as it contributes to increased fish production and water quality. In addition to increases in pH and alkalinity, such additions may reduce water-dissolved metal concentrations, change water transparency and bring about alterations in species diversity. Neutralization experiments have shown that an increase in water alkalinity and DOC may reduce the acute toxicity of Cu to fish. However, the influence of water quality on metal availability and accumulation has received scant attention. Earlier work showed that tissue metal concentrations in crayfish were related to the distance from the emission site. The purpose of the present study is to compare concentrations of six metals in freshwater crayfish from a neutralized acidic lake and a closely situated non-acidic lake. Various tissue concentrations in crayfish are also examined to determine specific tissue sites for these accumulations.

  14. Spectroscopic studies of the interaction mechanisms between mono-caffeoylquinic acids and transferrin.

    PubMed

    Guan, Yanqing; Dong, Jing; Chen, Shizhong; Liu, Meixian; Wang, Daidong; Zhang, Xiaotian; Wang, Hong; Lin, Zongtao

    2017-03-07

    Transferrin (Tf) is an important protein responsible for circulating and transporting iron into cytoplasm. Tf can be taken into cells through endocytosis mediated by Tf receptor, which usually overexpresses in cancer cells. The Tf-Tf receptor pathway opens a possible avenue for novel targeted cancer therapy by utilizing Tf-binding active compounds. Among which, anti-cancer active caffeoylquinic acids (CQAs) were recently found to be promising Tf-binders by our group. For better understanding the anti-cancer activities of CQAs, it is important to unveil the binding mechanisms between CQAs and Tf. In this study, the fluorescence quenching, surface plasmon resonance (SPR), circular dichroism (CD) and molecular docking were used to investigate the interactions between CQA and Tf. The results showed that the calculated apparent association constants of interactions between 1-, 3-, 4- and 5-CQA and Tf at 298K were 7.97×10(5)M(-1), 4.36×10(7)M(-1), 6.58×10(5)M(-1) and 4.42×10(6)M(-1), respectively. The thermodynamic parameters indicated that the interaction between 1-, 3-, 5-CQA and Tf is due to H-bonding, and electrostatic interactions were likely involved in the binding of 4-CQA and Tf. The CD results indicated that bindings of 1-CQA, 4-CQA and 5-CQA with Tf resulted in more stretched β-turn and random coil translated from β-sheet. In contrast, 3-CQA led to more stable a-helix conformation. Molecular docking studies of CQAs with Tf further displayed that CQAs were able to interact with residues near Fe(3+) binding site. The spectroscopic studies revealed the action mechanisms, thermodynamics and interacting forces between CQAs and Tf, and thus are helpful for future design and discovery of Tf-binders for targeted cancer therapy applying Tf-Tf receptor pathway.

  15. Application of a combined measurement and modeling method to quantify windblown dust emissions from the exposed playa at Mono Lake, California.

    PubMed

    Ono, Duane; Kiddoo, Phill; Howard, Christopher; Davis, Guy; Richmond, Kenneth

    2011-10-01

    Particulate matter < or =10 microm (PM10) emissions due to wind erosion can vary dramatically with changing surface conditions. Crust formation, mechanical disturbance, soil texture, moisture, and chemical content of the soil can affect the amount of dust emitted during a wind event. A refined method of quantifying windblown dust emissions was applied at Mono Lake, CA, to account for changing surface conditions. This method used a combination of real-time sand flux monitoring, ambient PM10 monitoring, and dispersion modeling to estimate dust emissions and their downwind impact. The method identified periods with high emissions and periods when the surface was stable (no sand flux), even though winds may have been high. A network of 25 Cox sand catchers (CSCs) was used to measure the mass of saltating particles to estimate sand flux rates across a 2-km2 area. Two electronic sensors (Sensits) were used to time-resolve the CSC sand mass to estimate hourly sand flux rates, and a perimeter tapered element oscillating microbalance (TEOM) monitor measured hourly PM10 concentrations. Hourly sand flux rates were related by dispersion modeling to hourly PM10 concentrations to back-calculate the ratio of vertical PM10 flux to horizontal sand flux (K-factors). Geometric mean K-factor values (K(f)) were found to change seasonally, ranging from 1.3 x 10(-5) to 5.1 x 10(-5) for sand flux measured at 15 cm above the surface (q15). Hourly PM10 emissions, F, were calculated by applying seasonal K-factors to sand flux measurements (F = K(f) x q15). The maximum hourly PM10 emission rate from the study area was 76 g/m2 x hr (10-m wind speed = 23.5 m/sec). Maximum daily PM10 emissions were estimated at 450 g/m2 x day, and annual emissions at 1095 g/m2 x yr. Hourly PM10 emissions were used by the U.S. Environmental Protection Agency (EPA) guideline AERMOD dispersion model to estimate downwind ambient impacts. Model predictions compared well with monitor concentrations, with hourly PM10

  16. Application of a Combined Measurement and Modeling Method to Quantify Windblown Dust Emissions from the Exposed Playa at Mono Lake, California.

    PubMed

    Ono, Duane; Kiddoo, Phill; Howard, Christopher; Davis, Guy; Richmond, Kenneth

    2011-10-01

    Particulate matter ≤10 μm (PM10) emissions due to wind erosion can vary dramatically with changing surface conditions. Crust formation, mechanical disturbance, soil texture, moisture, and chemical content of the soil can affect the amount of dust emitted during a wind event. A refined method of quantifying windblown dust emissions was applied at Mono Lake, CA, to account for changing surface conditions. This method used a combination of real-time sand flux monitoring, ambient PM10 monitoring, and dispersion modeling to estimate dust emissions and their downwind impact. The method identified periods with high emissions and periods when the surface was stable (no sand flux), even though winds may have been high. A network of 25 Cox sand catchers (CSCs) was used to measure the mass of saltating particles to estimate sand flux rates across a 2-km(2) area. Two electronic sensors (Sensits) were used to time-resolve the CSC sand mass to estimate hourly sand flux rates, and a perimeter tapered element oscillating microbalance (TEOM) monitor measured hourly PM10 concentrations. Hourly sand flux rates were related by dispersion modeling to hourly PM10 concentrations to back-calculate the ratio of vertical PM10 flux to horizontal sand flux (K-factors). Geometric mean K-factor values (K f) were found to change seasonally, ranging from 1.3 × 10(-5) to 5.1 × 10(-5) for sand flux measured at 15 cm above the surface (q 15). Hourly PM10 emissions, F, were calculated by applying seasonal K-factors to sand flux measurements (F = K f × q 15). The maximum hourly PM10 emission rate from the study area was 76 g/m(2)·hr (10-m wind speed = 23.5 m/sec). Maximum daily PM10 emissions were estimated at 450 g/m(2)·day, and annual emissions at 1095 g/m(2)·yr. Hourly PM10 emissions were used by the U.S. Environmental Protection Agency (EPA) guideline AERMOD dispersion model to estimate downwind ambient impacts. Model predictions compared well with monitor concentrations, with

  17. Acid precipitation effects on algal productivity and biomass in Adirondack Lakes. Final completion report

    SciTech Connect

    Hendrey, G.R.

    1982-12-01

    Relationships between phytoplankton communities and lake acidity in three Adirondack Mountain Lakes were studied at Woods Lake, Sagamore Lake (pH ca. 5.5), and Panther Lake (pH ca. 7.0). Numbers of phytoplankton species observed were Woods 45, Sagamore 55, and Panther 85, conforming to observations at many other sites that species numbers decrease with increasing acidity. The smaller plankton are relatively more important in the more acid lakes, Woods > Sagamore > Panther. This pattern could be determined by nutrient availability (lake acidification is suspected of leading to decreased availability of phosphorus). The amount of 14C-labelled dissolved photosynthate (14C-DOM), as a percent of total productivity, is ordered Woods > Sagamore > Panther.

  18. Recovery of Daphnia galeata mendotae in two historically acid and metal contaminated lakes after liming

    SciTech Connect

    Welsh, P.G.; Yan, N.; Hangang, L.; Dixon, D.G.

    1994-12-31

    Daphnia galeata mendotae (DGM) has recently re-appeared in Hannah and Middle Lake, two lakes historically stressed by acid and metals. These lakes were limed in the early 1970s. Since then, the lakes have remained non-acidic but metal levels have declined monotonically. DGM became a dominant zooplankton species in Hannah Lake approximately 5 years before Middle Lake. One hypothesis for this temporal displacement in recovery is available metal concentrations regulating recovery in the two lakes. The authors examined the chronic toxicity of Cu, Cd, and Ni mixtures to DGM in the laboratory with lake water manipulated to correspond to metal concentrations in successive 4--5 year increments (1976, 1981, 1985, 1989, and 1993). Cultures of DGM were established from both lakes. Survivorship and, especially, number of living offspring produced were sensitive indicators of past metal conditions. Conditions representative of 1976 lake water (immediately post-liming) were acutely lethal to both DGM populations. Hannah Lake DGM had higher survivorship and number of live offspring produced for all of the remaining simulated lake conditions. These results correspond well with field assessment of the timing of recovery of DGM in both lakes.

  19. Electrocatalysis of chloroacetic acids (mono-, di- and tri-) at a C60-[dimethyl-(beta-cyclodextrin)]2 and nafion chemically modified electrode.

    PubMed

    Wei, M; Li, M; Li, N; Gu, Z; Zhou, X

    2001-01-26

    The C(60)-[dimethyl-(beta-cyclodextrin)](2) and nafion chemically modified electrode (CME) exhibits one electroreduction peak and two electro-oxidation peaks in a mixed solvent of water and acetonitrile (3:2, v/v) containing tetra-butylammonium perchlorate. The reduction of chloroacetic acids (mono-, di- and tri-) can be electrocatalyzed at this electrode, indicating that C(60)-[dimethyl-(beta-cyclodextrin)](2) is capable of mediating the electron transfer to chloroacetic acids. Values of the apparent catalytic rate constant, k, were determined by using the rotating-disk electrode (RDE).

  20. Assessment of lake sensitivity to acidic deposition in national parks of the Rocky Mountains.

    PubMed

    Nanus, L; Williams, M W; Campbell, D H; Tonnessen, K A; Blett, T; Clow, D W

    2009-06-01

    The sensitivity of high-elevation lakes to acidic deposition was evaluated in five national parks of the Rocky Mountains based on statistical relations between lake acid-neutralizing capacity concentrations and basin characteristics. Acid-neutralizing capacity (ANC) of 151 lakes sampled during synoptic surveys and basin-characteristic information derived from geographic information system (GIS) data sets were used to calibrate the statistical models. The explanatory basin variables that were considered included topographic parameters, bedrock type, and vegetation type. A logistic regression model was developed, and modeling results were cross-validated through lake sampling during fall 2004 at 58 lakes. The model was applied to lake basins greater than 1 ha in area in Glacier National Park (n = 244 lakes), Grand Teton National Park (n = 106 lakes), Great Sand Dunes National Park and Preserve (n = 11 lakes), Rocky Mountain National Park (n = 114 lakes), and Yellowstone National Park (n = 294 lakes). Lakes that had a high probability of having an ANC concentration <100 microeq/L, and therefore sensitive to acidic deposition, are located in basins with elevations >3000 m, with <30% of the catchment having northeast aspect and with >80% of the catchment bedrock having low buffering capacity. The modeling results indicate that the most sensitive lakes are located in Rocky Mountain National Park and Grand Teton National Park. This technique for evaluating the lake sensitivity to acidic deposition is useful for designing long-term monitoring plans and is potentially transferable to other remote mountain areas of the United States and the world.

  1. On the microstructure of organic solutions of mono-carboxylic acids: Combined study by infrared spectroscopy, small-angle neutron scattering and molecular dynamics simulations

    NASA Astrophysics Data System (ADS)

    Eremin, Roman A.; Kholmurodov, Kholmirzo T.; Petrenko, Viktor I.; Rosta, László; Grigoryeva, Natalia A.; Avdeev, Mikhail V.

    2015-11-01

    The data of infrared spectroscopy (IR), molecular dynamics (MD) simulations and small-angle neutron scattering (SANS) have been combined to conclude about the nanoscale structural organization of organic non-polar solutions of saturated mono-carboxylic acids with different alkyl chain lengths for diluted solutions of saturated myristic (C14) and stearic (C18) acids in benzene and decalin. In particular, the degree of dimerization was found from the IR spectra. The structural anisotropy of the acids and their dimers was used in the treatment of the data of MD simulations to describe the solute-solvent interface in a cylindrical approximation and show its rather strong influence on SANS. The corresponding scattering length density profiles were used to fit the experimental SANS data comprising the information about the acid molecule isomerization. The SANS data from concentrated solutions showed a partial self-assembling of the acids within the nematic transition is different for two solvents due to lyophobic peculiarities.

  2. A Demonstration of Acid Rain and Lake Acidification: Wet Deposition of Sulfur Dioxide.

    ERIC Educational Resources Information Center

    Goss, Lisa M.

    2003-01-01

    Introduces a science demonstration on the dissolution of sulfuric oxide emphasizing the concept of acid rain which is an environmental problem. Demonstrates the acidification from acid rain on two lake environments, limestone and granite. Includes safety information. (YDS)

  3. Catchment and atmospheric effects on acidity of lakes in the northeastern United States

    SciTech Connect

    Davis, R.B.; Anderson, D.S.; Rhodes, T.E.

    1995-06-01

    Sedimentary evidence from 12 lakes in northeastern United States reveals that both catchment and atmospheric processes have caused changes in lake acidity. Diatom remains indicate pH 5.2 to 5.8 (one lake 6.8) for one to two centuries before impacts on the catchment by Euro-americans. These low-alkalinity lakes were very sensitive to altered fluxes of base cations and acids. Several lakes increased in pH by 0.2 to 0.6 unit in the 1800s and early 1900s when their catchments were logged. Re-acidification of some of the lakes was initially due to forest succession. Older sediment from one of the lakes also shows alkalization by natural disturbance, and acidification paralleling forest succession. However, much of the recent acidification, to uniquely low levels by the 1970s is due to high sulfur deposition.

  4. Biotinylation of a propargylated cyclic (3'-5') diguanylic acid and of its mono-6-thioated analog under "click" conditions.

    PubMed

    Grajkowski, Andrzej; Cieślak, Jacek; Schindler, Christian; Beaucage, Serge L

    2013-03-01

    Commercial N(2)-isobutyryl-5'-O-(4,4'-dimethoxytrityl)-2'-O-(propargyl)guanosine is converted to its 3'-O-levulinyl ester in a yield of 91%. The reaction of commercial N(2)-isobutyryl-5'-O-(4,4'-dimethoxytrityl)-2'-O-tert-butyldimethylsilyl-3'-O-[(2-cyanoethyl)-N,N-diisopropylaminophosphinyl]guanosine with N(2)-isobutyryl-2'-O-propargyl-3'-O-(levulinyl)guanosine provides, after P(III) oxidation, 3'-/5'-deprotection, and purification, the 2'-O-propargylated guanylyl(3'-5')guanosine 2-cyanoethyl phosphate triester in a yield of 88%. Phosphitylation of this dinucleoside phosphate triester with 2-cyanoethyl tetraisopropylphosphordiamidite and 1H-tetrazole, followed by an in situ intramolecular cyclization, gives the propargylated cyclic dinucleoside phosphate triester, which is isolated in a yield of 40% after P(III) oxidation and purification. Complete removal of the nucleobases, phosphates, and 2'-O-tert-butyldimethylsilyl protecting groups leads to the desired propargylated c-di-GMP diester. Cycloaddition of a biotinylated azide with the propargylated c-di-GMP diester under click conditions provides the biotinylated c-di-GMP conjugate in an isolated yield of 62%. Replacement of the 6-oxo function of N(2)-isobutyryl-5'-O-(4,4'-dimethoxytrityl)-3'-O-levulinyl-2'-O-(propargyl)guanosine with a 2-cyanoethylthio group is effected by treatment with 2,4,6-triisopropybenzenesulfonyl chloride and triethylamine to give a 6-(2,4,6-triisopropylbenzenesulfonic acid) ester intermediate. Reaction of this key intermediate with 3-mercaptoproprionitrile and triethylamine, followed by 5'-dedimethoxytritylation, affords the 6-(2-cyanoethylthio)guanosine derivative in a yield of 70%. The 5'-hydroxy function of this derivative is reacted with commercial N(2)-isobutyryl-5'-O-(4,4'-dimethoxytrityl)-2'-O-tert-butyldimethylsilyl-3'-O-[(2-cyanoethyl)-N,N-diisopropylaminophosphinyl]guanosine. The reaction product is then converted to the mono-6-thioated c-di- GMP biotinylated conjugate under

  5. Evaluation of the recovery of Adirondack acid lakes by chemical manipulation

    SciTech Connect

    Depinto, J.V.; Edzwald, J.K.

    1982-06-01

    This study specifically addressed an evaluation of materials (calcium hydroxide and carbonate, agricultural limestone, fly ash, water treatment plant softening sludge, cement plant by-pass dust) for their neutralizing effectiveness and for establishing a neutral pH buffer system, and an evaluation of the effect of various lake recovery materials on algal growth. Laboratory continuous-flow microcosims were used as models to assess acid lake recovery. These models were filled with actual acid lake water over a layer of lake sediments, subjected to a given chemical treatment, and continuously fed water of selected quality (e.g., acid rain). A simulation of sediment-water-air kinetic interactions on a treated acid lake was obtained by careful monitoring of the microcosm chemical response. Agricultural limestone was determined to be the most appropriate material for acid lake recovery treatment based on its neutralizing properties, assessment of its potential impact on biota, its availability, and its relative cost: the results of this laboratory study suggest that full-scale recovery of an Adirondack acid lake is technically feasible. It is, however, recommended that an acid lake recovery field demonstration project be undertaken. 58 references, 36 figures, 29 tables.

  6. Perfluorinated acids in air, rain, snow, surface runoff, and lakes: relative importance of pathways to contamination of urban lakes.

    PubMed

    Kim, Seung-Kyu; Kannan, Kurunthachalam

    2007-12-15

    Concentrations of perfluorinated acids (PFAs) were measured in various environmental matrices (air, rain, snow, surface runoff water, and lake water) in an urban area, to enable identification of sources and pathways of PFAs to urban water bodies. Total PFA concentrations ranged from 8.28 to 16.0 pg/ m3 (mean 11.3) in bulk air (sum of vapor and particulate phases), 0.91 to 13.2 ng/L (6.19) in rainwater, 0.91 to 23.9 ng/L (7.98) in snow, 1.11-81.8 ng/L (15.1 ng/L) in surface runoff water (SRW), and 9.49 to 35.9 ng/L (21.8) in lake water. Perfluorooctanoic acid (PFOA) was the predominant compound, accounting for > 35% of the total PFA concentrations, in all environmental matrices analyzed. Concentrations and relative compositions of PFAs in SRW were similar to those found for urban lakes. SRW contributes to contamination by PFOA in urban lakes. The measured concentration ratios of FTOH to PFOA in air were 1-2 orders of magnitude lower than the ratios calculated based on an assumption of exclusive atmospheric oxidation of FTOHs. Nevertheless, the mass balance analysis suggested the presence of an unknown input pathway that could contribute to a significant amount of total PFOA loadings to the lake. Flux estimates of PFOA at the air-water interface in the urban lake suggest net volatilization from water.

  7. Acid precipitation effects on algal productivity and biomass in Adirondack Mountain lakes

    SciTech Connect

    Hendrey, G.R.

    1982-12-01

    Relationships between phytoplankton communities and lake acidity in three Adirondack Mountain lakes were studied at Woods Lake (pH ca. 4.9), Sagamore Lake (pH ca. 5.5), and Panther Lake (pH ca. 7.0). Species numbers decrease with increasing acidity. Patterns of increasing biomass and productivity in Woods Lake may be atypical of similar oligotrophic lakes in that they develop rather slowly to maxima six weeks after ice-out, instead of occurring very close to ice-out. Contributions of netplankton, nannoplankton and ultraplankton to productivity per m/sup 2/ show that the smaller plankton are relatively more important in the more acid lakes. This pattern could be determined by nutrient availability (lake acidification is suspected of leading to decreased availability of phosphorus). This was consistent with a hypothesis that microbial heterotrophic activity is reduced with increasing acidity, but the smaller phytoplankton may be more leaky at low pH. 11 references, 2 tables.

  8. Parent Body Influences on Amino Acids in the Tagish Lake Meteorite

    NASA Technical Reports Server (NTRS)

    Glavin, D. P.; Callahan, M. P.; Dworkin, J. P.; Elsila, J. E.; Herd, C. D. K.

    2010-01-01

    The Tagish Lake meteorite is a primitive C2 carbonaceous chondrite with a mineralogy, oxygen isotope, and bulk chemical. However, in contrast to many CI and CM carbonaceous chondrites, the Tagish Lake meteorite was reported to have only trace levels of indigenous amino acids, with evidence for terrestrial L-amino acid contamination from the Tagish Lake meltwater. The lack of indigenous amino acids in Tagish Lake suggested that they were either destroyed during parent body alteration processes and/or the Tagish Lake meteorite originated on a chemically distinct parent body from CI and CM meteorites where formation of amino acids was less favorable. We recently measured the amino acid composition of three different lithologies (11h, 5b, and 11i) of pristine Tagish Lake meteorite fragments that represent a range of progressive aqueous alteration in order 11h < 5b < 11i as inferred from the mineralogy, petrology, bulk isotopes, and insoluble organic matter structure. The distribution and enantiomeric abundances of the one- to six-carbon aliphatic amino acids found in hot-water extracts of the Tagish Lake fragments were determined by ultra performance liquid chromatography fluorescence detection and time of flight mass spectrometry coupled with OPA/NAC derivatization. Stable carbon isotope analyses of the most abundant amino acids in 11h were measured with gas chromatography coupled with quadrupole mass spectrometry and isotope ratio mass spectrometry.

  9. Spatial characterization of acid rain stress in Canadian Shield lakes. Progress report, 1 August 1985-1 February 1986

    SciTech Connect

    Tanis, F.J.

    1986-01-01

    The acidification of lake waters from airborne pollutants is of continental proportions both in North America and Europe. A major concern of the acid rain problem is the cumulative ecosystem damage to lakes and forest. The number of lakes affected in northeastern United States and on the Canadian Shield is though to be enormous. The principle objective is to examine how seasonal changes in lake water transparency are related to annual acidic load. Further, the relationship between variations in lake acidification and ecophysical units is being examined. Finally, the utility of Thematic Mapper (TM) based observations to measure seasonal changes in the optical transparency in acid lakes is being investigated.

  10. Geochemistry, mineralogy, and chemical modeling of the acid crater lake of Kawah Ijen Volcano, Indonesia

    NASA Astrophysics Data System (ADS)

    Delmelle, Pierre; Bernard, Alain

    1994-06-01

    The Kawah Ijen volcano—with a record of phreatic eruptions—has its 1000 m wide crater filled with a lake that has existed for at least one century. At present, the lake waters are hot ( T ≈ 37° C), strongly mineralized (TDS = 105 g/L) and extremely acidic ( pH ≈ 0.4). By its volume, the Javanese lake is probably the largest accumulation in the world of such acidic waters. Mineralogy of the suspended solids within the lake waters suggests that concentrations of Si, Ca, Ti, and Ba are controlled by precipitation of silica, gypsum, anatase, and barite. Lake sediment is composed of chemical precipitates with composition similar to the suspended solids. Thermodynamic calculations predict that the lake waters have reached equilibrium with respect to α-cristobalite, barite, gypsum, anglesite, celestite, and amorphous silica, in agreement with the analytical observations. Significant concentrations of ferric iron suggest that the current lake waters are fairly oxidized. Sulfides are absent in the water column but are always present in the native S spherules that form porous aggregates which float on the lake. The presence of native S provides direct evidence of more reduced conditions at the lake floor where H 2S is probably being injected into the lake. With progressive addition of H 2S to the acid waters, native S, pyrite, and enargite are theoretically predicted to be saturated. Reactions between upward streaming H 2S-bearing gases discharged by subaqueous fumaroles, and metals dissolved in the acidic waters could initiate precipitation of these sulfides. A model of direct absorption of hot magmatic gases into cool water accounts for the extreme acidity of the crater lake. Results show that strongly acidic, sulfate-rich solutions are formed under oxidizing conditions at high gas/water ratios. Reactions between the acidic fluids and the Ijen andesite were modeled to account for elevated cation concentrations in lake water. Current concentrations of conservative

  11. Hydrogeologic comparison of an acidic-lake basin with a neutral-lake basin in the West-Central Adirondack Mountains, New York

    USGS Publications Warehouse

    Peters, N.E.; Murdoch, Peter S.

    1985-01-01

    Two small headwater lake basins that receive similar amounts of acidic atmospheric deposition have significantly different lake outflow pH values; pH at Panther Lake (neutral) ranges from about 4.7 to 7; that at Woods Lake (acidic) ranges from about 4.3 to 5. A hydrologic analysis, which included monthly water budgets, hydrograph analysis, examination of flow duration and runoff recession curves, calculation of ground-water storage, and an analysis of lateral flow capacity of the soil, indicates that differences in lakewater pH can be attributed to differences in the ground-water contribution to the lakes. A larger percentage of the water discharged from the neutral lake is derived from ground water than that from the acidic lake. Ground water has a higher pH resulting from a sufficiently long residence time for neutralizing chemical reactions to occur with the till. The difference in ground-water contribution is attributed to a more extensive distribution of thick till (<3m) in the neutral-lake basin than in the acidic-lake basin; average thickness of till in the neutral-lake basin is 24m whereas that in the other is 2.3m. During the snowmelt period, as much as three months of accumulated precipitation may be released within two weeks causing the lateral flow capacity of the deeper mineral soil to be exceeded in the neutral-lake basin. This excess water moves over and through the shallow acidic soil horizons and causes the lakewater pH to decrease during snowmelt.Two small headwater lake basins that receive similar amounts of acidic atmospheric deposition have significantly different lake outflow pH values; pH at Panther Lake (neutral) ranges from about 4. 7 to 7; that at Woods Lake (acidic) ranges from about 4. 3 to 5. A hydrologic analysis, which included monthly water budgets, hydrograph analysis, examination of flow duration and runoff recession curves, calculation of ground-water storage, and an analysis of lateral flow capacity of the soil, indicates that

  12. Separation of some mono-, di- and tri-unsaturated fatty acids containing 18 carbon atoms by high-performance liquid chromatography and photodiode array detection.

    PubMed

    Czauderna, M; Kowalczyk, J

    2001-08-25

    Positional and geometric isomers of mono-, di- and tri-unsaturated fatty acids containing 18 carbon atoms were separated on commercially available reversed-phase columns in gradient systems composed of acetonitrile and water, utilizing photodiode array detection. The biological samples were hydrolyzed with 2 M NaOH for 35-40 min at 85-90 degrees C. After cooling, the hydrolysates were acidified with 4 M HCl and the free fatty acids were extracted with dichloromethane. The organic solvent was removed in a gentle stream of argon. The fatty acids were determined after pre-column derivatization with dibromacetophenone in the presence of triethylamine. The reaction components were mixed and reacted for 2 h at 50 degrees C. Separations of derivatized fatty acids were performed on two C18 columns (Nova Pak C18, 4 microm, 250x4.6 mm, Waters) by binary or ternate gradient programs and UV detection at 254 and 235 nm. The geometric and positional isomers of some unsaturated fatty acids were substantially retained on the C18 columns and were distinct from some saturated fatty acids, endogenous substances in biological samples or background interference. Only slight separation of critical pairs of cis-9 C18:1/cis-11 C18:1 and cis-6 C18:1/trans-11 C18:1 was obtained. A ternate gradient program can be used for complete fractionation of a mixture of conjugated linoleic acid isomers (CLA) from cis-9, cis-12 and trans-9, trans-12 isomers of C18:2. The CLA isomers in the effluent were monitored at 235 nm. The CLA isomers were differentiated from saturated and unsaturated fatty acids using a photodiode array detector. The utility of the method was demonstrated by evaluating the fatty acid composition of duodenal digesta, rapeseed and maize oils.

  13. Chemical and biological characteristics of Emerald Lake and the streams in its watershed and the responses of the lake and streams to acidic deposition. Final report

    SciTech Connect

    Melack, J.M.; Cooper, S.D.; Jenkins, T.M.; Barmuta, L.; Hamilton, S.

    1989-03-14

    This report describes the results of field work conducted at Emerald Lake in Sequoia National Park during the period of 1983-88, with an emphasis on the effects of acid deposition on a high-elevation lake in the Sierra Nevada. Time-series data were collected for major ions, nutrients, trace metals, chlorophyll, zooplankton and zoobenthos. Mass balances were calculated for major solutes in the lake, including analysis of the inflows and major solutes in the lake, including analysis of the inflows and outflow from the lake. The ecology and population dynamics of the resident population of brook trout were studied in detail. Biological surveys indicated the presence of the Pacific tree frog in small ponds in the vicinity of Emerald Lake. Experimental acidification of large bags in the lake was used to develop dose-response relationships for the major zooplankton species, especially Daphnia. The conclusion of the research to date is that Emerald Lake is not currently showing serious chemical or biological effects of acidification. Acid-sensitive animals are found in the lake and associated streams. The surface waters of the Emerald Basin are extremely dilute and ANC-generating processes in the lake are small compared to that of the watershed. Acidic episodes have been recorded. If these episodes were to increase, the surface waters and the biological populations could be readily affected.

  14. Aquatic fulvic acids in microbially based ecosystems: results from two desert lakes in Antarctica

    USGS Publications Warehouse

    McKnight, Diane M.; Aiken, G.R.; Smith, R.L.

    1991-01-01

    These lakes receive very limited input of organic material from the surrounding barren desert, but they sustain algal and bacterial populations under permanent ice cover. One lake has an extensive anoxic zone and high salinities; the other is oxic and has low salinities. Despite these differences, fulvic acids from both lakes had similar elemental compositions, carbon distributions, and amino acid contents, indicating that the chemistry of microbially derived fulvic acvids is not strongly influenced by chemical conditions in the water column. Compared to fulvic acids from other natural waters, these fulvic acids have low C:N atomic ratios (19-25) and low contents of aromatic carbons (5-7% of total carbon atoms); they are most similar to marine fulvic acids. -from Authors

  15. Seasonal and spatial variations in phytoplanktonic chlorophyll in eutrophic Mono Lake, California, measured with the Airborne Visible and Infrared Imaging Spectrometer (AVIRIS)

    NASA Technical Reports Server (NTRS)

    Melack, John M.; Gastil, Mary

    1992-01-01

    The principal problem with application of airborne imaging spectrometers to lakes is the weak upwelling signal, especially when narrow spectral bands with high spatial resolution are sought. Furthermore, atmospheric path radiance dominates the signal received from dark targets such as lakes. Once atmospheric effects have been removed from the radiance received at the sensor, semi-empirical relationships can be developed to extract information about phytoplankton pigment concentrations for different underwater optical conditions. In lakes where concentrations of dissolved organics and suspended detritus may not co-vary with phytoplankton pigments, the many spectral channels of an imaging spectrometer such as AVIRIS are likely to be required to distinguish the various aquasols. The objectives of our study are to: (1) estimate the chlorophyll content of a lake with hundred-fold seasonal ranges in chlorophyll concentration using atmospherically corrected upwelling radiances derived from AVIRIS imagery, and (2) to examine spatial patterns in chlorophyll after reduction of the coherent noise in the imagery by filtering techniques.

  16. Coccomyxa: a dominant planktic alga in two acid lakes of different origin.

    PubMed

    Barcytė, Dovilė; Nedbalová, Linda

    2017-03-01

    The aim of this study was to reveal the taxonomic position and phylogenetic relationships of the dominant planktic algae in two acid metal-rich lakes of different origin (Hromnice Lake and Plešné Lake, Czech Republic) and to investigate their morphology and ultrastructure under natural and laboratory conditions. Phylogenetic analyses (18S rRNA and ITS-2) revealed that the strain isolated from Hromnice Lake belongs to the species Coccomyxa elongata, while Coccomyxa from Plešné Lake was described as a new species C. silvae-gabretae. It is the first evidence that representatives of this genus are capable of becoming the dominant primary producers in the extreme environment of acid lakes with an increased supply of phosphorus. There were clear differences in cell morphology under different growth conditions, revealing the high phenotypic plasticity of the strains. The ability to change the morphology may help the cells of Coccomyxa to survive harsh conditions in the aforementioned acid lakes.

  17. Lake

    ERIC Educational Resources Information Center

    Wien, Carol Anne

    2008-01-01

    The lake is blue black and deep. It is a glaciated finger lake, clawed out of rock when ice retracted across Nova Scotia in a northerly direction during the last ice age. The lake is narrow, a little over a mile long, and deep, 90 to 190 feet in places according to local lore, off the charts in others. The author loves to swim there, with a sense…

  18. Patterns of nutrient dynamics in Adirondack lakes recovering from acid deposition.

    PubMed

    Gerson, Jacqueline R; Driscoll, Charles T; Roy, Karen M

    2016-09-01

    With decreases in acid deposition, nitrogen : phosphorus (N:P) ratios in lakes are anticipated to decline, decreasing P limitation of phytoplankton and potentially changing current food web dynamics. This effect could be particularly pronounced in the Adirondack Mountains of New York State, a historic hotspot for effects of acid deposition. In this study, we evaluate spatial patterns of nutrient dynamics in Adirondack lakes and use these to infer potential future temporal trends. We calculated Mann-Kendall tau correlations among total phosphorus (TP), chlorophyll a, dissolved organic carbon (DOC), acid neutralizing capacity (ANC), and nitrate (NO3(-) ) concentrations in 52 Adirondack Long Term Monitoring (ALTM) program lakes using samples collected monthly during 2008-2012. We evaluated the hypothesis that decreased atmospheric N and S deposition will decrease P limitation in freshwater ecosystems historically impacted by acidification. We also compared these patterns among lake watershed characteristics (i.e., seepage or lacking a surface outlet, chain drainage, headwater drainage, thin glacial till, medium glacial till). We found that correlations (P < 0.05) were highly dependent upon the different hydrologic flowpaths of seepage vs. drainage lakes. Differentiations among watershed till depth were also important in determining correlations due to water interaction with surficial geology. Additionally, we found low NO3(-) :TP (N:P mass) values in seepage lakes (2.0 in winter, 1.9 in summer) compared to chain drainage lakes (169.4 in winter, 49.5 in summer) and headwater drainage lakes (97.0 in winter, 10.9 in summer), implying a high likelihood of future shifts in limitation patterns for seepage lakes. With increasing DOC and decreasing NO3(-) concentrations coinciding with decreases in acid deposition, there is reason to expect changes in nutrient dynamics in Adirondack lakes. Seepage lakes may become N-limited, while drainage lakes may become less P

  19. Potential for acid precipitation damage to lakes of the Sierra Nevada, California

    SciTech Connect

    Harte, J.; Holdren, J.; Tonnesson, K.

    1983-04-01

    One of the areas of California potentially sensitive to acidic deposition is the Sierra Nevada, located along the eastern boundary. A report on sensitive areas in North America identifies the Sierra as a region characterized by poorly buffered soils and granite based lakes. The subalpine and alpine lakes in this region share many of the characteristics of lakes adversely affected by acid deposition in other parts of the US and the world. For this investigation selected subalpine lakes of the western slope of the Sierra were chosen for study, to establish baseline water quality which would allow for the identification of chemical and biological changes due to acidic deposition. It was then attempted to simulate the ecosystem stress of increased acidic deposition, particularly in the form of snowmelt, on these systems by performing microcosm experiments in the laboratory. These experiments were particularly concerned with recording changes in concentrations of micronutrients which might be leached from lake sediments with increasing acidification. This phenomenon is particularly important to study in the light of finds on the importance of aluminum leaching in the northeast which was led to toxic effects of biota in Adirondack lakes. 10 references, 3 figures, 1 table.

  20. Growing spherulitic calcite grains in saline, hyperalkaline lakes: experimental evaluation of the effects of Mg-clays and organic acids

    NASA Astrophysics Data System (ADS)

    Mercedes-Martín, R.; Rogerson, M. R.; Brasier, A. T.; Vonhof, H. B.; Prior, T. J.; Fellows, S. M.; Reijmer, J. J. G.; Billing, I.; Pedley, H. M.

    2016-04-01

    The origin of spherical-radial calcite bodies - spherulites - in sublacustrine, hyperalkaline and saline systems is unclear, and therefore their palaeoenvironmental significance as allochems is disputed. Here, we experimentally investigate two hypotheses concerning the origin of spherulites. The first is that spherulites precipitate from solutions super-saturated with respect to magnesium-silicate clays, such as stevensite. The second is that spherulite precipitation happens in the presence of dissolved, organic acid molecules. In both cases, experiments were performed under sterile conditions using large batches of a synthetic and cell-free solution replicating waters found in hyperalkaline, saline lakes (such as Mono Lake, California). Our experimental results show that a highly alkaline and highly saline solution supersaturated with respect to calcite (control solution) will precipitate euhedral to subhedral rhombic and trigonal bladed calcite crystals. The same solution supersaturated with respect to stevensite precipitates sheet-like stevensite crystals rather than a gel, and calcite precipitation is reduced by ~ 50% compared to the control solution, producing a mixture of patchy prismatic subhedral to euhedral, and minor needle-like, calcite crystals. Enhanced magnesium concentration in solution is the likely the cause of decreased volumes of calcite precipitation, as this raised equilibrium ion activity ratio in the solution. On the other hand, when alginic acid was present then the result was widespread development of micron-size calcium carbonate spherulite bodies. With further growth time, but falling supersaturation, these spherules fused into botryoidal-topped crusts made of micron-size fibro-radial calcite crystals. We conclude that the simplest tested mechanism to deposit significant spherical-radial calcite bodies is to begin with a strongly supersaturated solution that contains specific but environmentally-common organic acids. Furthermore, we found

  1. Unusual nonterrestrial L-proteinogenic amino acid excesses in the Tagish Lake meteorite

    NASA Astrophysics Data System (ADS)

    Glavin, Daniel P.; Elsila, Jamie E.; Burton, Aaron S.; Callahan, Michael P.; Dworkin, Jason P.; Hilts, Robert W.; Herd, Christopher D. K.

    2012-08-01

    The distribution and isotopic and enantiomeric compositions of amino acids found in three distinct fragments of the Tagish Lake C2-type carbonaceous chondrite were investigated via liquid chromatography with fluorescence detection and time-of-flight mass spectrometry and gas chromatography isotope ratio mass spectrometry. Large L-enantiomeric excesses (Lee ˜ 43-59%) of the α-hydrogen aspartic and glutamic amino acids were measured in Tagish Lake, whereas alanine, another α-hydrogen protein amino acid, was found to be nearly racemic (D ≈ L) using both techniques. Carbon isotope measurements of D- and L-aspartic acid and D- and L-alanine in Tagish Lake fall well outside of the terrestrial range and indicate that the measured aspartic acid enantioenrichment is indigenous to the meteorite. Alternate explanations for the L-excesses of aspartic acid such as interference from other compounds present in the sample, analytical biases, or terrestrial amino acid contamination were investigated and rejected. These results can be explained by differences in the solid-solution phase behavior of aspartic acid, which can form conglomerate enantiopure solids during crystallization, and alanine, which can only form racemic crystals. Amplification of a small initial L-enantiomer excess during aqueous alteration on the meteorite parent body could have led to the large L-enrichments observed for aspartic acid and other conglomerate amino acids in Tagish Lake. The detection of nonterrestrial L-proteinogenic amino acid excesses in the Tagish Lake meteorite provides support for the hypothesis that significant enantiomeric enrichments for some amino acids could form by abiotic processes prior to the emergence of life.

  2. Unusual Nonterrestrial L-proteinogenic Amino Acid excesses in the Tagish Lake Meteorite

    NASA Technical Reports Server (NTRS)

    Glavin, Daniel P.; Elsila, Jamie E.; Burton, Aaron S.; Callahan, Michael P.; Dworkin, Jason P.; Hilts, Robert W.; Herd, D. K.

    2012-01-01

    The distribution and isotopic and enantiomeric compositions of amino acids found in three distinct fragments of the Tagish Lake C2-type carbonaceous chondrite were investigated via liquid chromatography with fluorescence detection and time-of-flight mass spectrometry and gas chromatography isotope ratio mass spectrometry. Large L-enantiomeric excesses (L(sub ee) approximately 43-59%) of the alpha-hydrogen aspartic and glutamic amino acids were measured in Tagish Lake, whereas alanine, another alpha hydrogen protein amino acid, was found to be nearly racemic (D much approximately L) using both techniques. Carbon isotope measurements of D- and L-aspartic acid and 1)- and L-alanine in Tagish Lake fall well outside of the terrestrial range and indicate that the measured aspartic acid enantioenrichment is indigenous to the meteorite. Alternate explanations for the L-excesses of aspartic acid such as interference from other compounds present in the sample, analytical biases, or terrestrial amino acid contamination were investigated and rejected. These results can be explained by differences in the solid-solution phase behavior of aspartic acid, which can form conglomerate enantiopure solids during crystallization, and alanine, which can only form racemic crystals. Amplification of a small initial L-enantiomer excess during aqueous alteration on the meteorite parent body could have led to the large L-enrichments observed for aspartic acid and other conglomerate amino acids in Tagish Lake. The detection of non terrestrial L-proteinogenic amino acid excesses in the Tagish Lake meteorite provides support for the hypothesis that significant enantiomeric enrichments for some amino acids could form by abiotic processes prior to the emergence of life.

  3. Selective transfer of polyunsaturated fatty acids from phytoplankton to planktivorous fish in large boreal lakes.

    PubMed

    Strandberg, Ursula; Hiltunen, Minna; Jelkänen, Elli; Taipale, Sami J; Kainz, Martin J; Brett, Michael T; Kankaala, Paula

    2015-12-01

    Lake size influences various hydrological parameters, such as water retention time, circulation patterns and thermal stratification that can consequently affect the plankton community composition, benthic-pelagic coupling and the function of aquatic food webs. Although the socio-economical (particularly commercial fisheries) and ecological importance of large lakes has been widely acknowledged, little is known about the availability and trophic transfer of polyunsaturated fatty (PUFA) in large lakes. The objective of this study was to investigate trophic trajectories of PUFA in the pelagic food web (seston, zooplankton, and planktivorous fish) of six large boreal lakes in the Finnish Lake District. Docosahexaenoic acid (DHA), eicosapentaenoic acid (EPA) and α-linolenic acid (ALA) were the most abundant PUFA in pelagic organisms, particularly in the zooplanktivorous fish. Our results show that PUFA from the n-3 family (PUFAn-3), often associated with marine food webs, are also abundant in large lakes. The proportion of DHA increased from ~4±3% in seston to ~32±6% in vendace (Coregonus albula) and smelt (Osmerus eperlanus), whereas ALA showed the opposite trophic transfer pattern with the highest values observed in seston (~11±2%) and the lowest in the opossum shrimp (Mysis relicta) and fish (~2±1%). The dominance of diatoms and cryptophytes at the base of the food web in the study lakes accounted for the high amount of PUFAn-3 in the planktonic consumers. Furthermore, the abundance of copepods in the large lakes explains the effective transfer of DHA to planktivorous fish. The plankton community composition in these lakes supports a fishery resource (vendace) that is very high nutritional quality (in terms of EPA and DHA contents) to humans.

  4. "Hairy blobs:" microbial suspects preserved in modern and ancient extremely acid lake evaporites.

    PubMed

    Benison, Kathleen C; Jagniecki, Elliot A; Edwards, Tina B; Mormile, Melanie R; Storrie-Lombardi, Michael C

    2008-08-01

    "Hairy blobs" are unusual clumps of organic bodies and sulfate crystals that have been found in evaporite minerals grown in acid saline lakes. Here, we document modern hairy blobs in halite and gypsum from 5 modern acid saline lakes in southern Western Australia, and Permian hairy blobs trapped in halite from the mid-Permian Opeche Shale in the subsurface of North Dakota. These are among the first microbial remains described from acid saline lake environments. They give clues about the role of microorganisms in the acidity, geochemistry, and mineralogy of these extreme environments. This study also may add to the inventory of life in extreme environments and help predict possible martian life-forms and the method of preservation.

  5. Adaptive reversals in acid tolerance in copepods from lakes recovering from historical stress.

    PubMed

    Derry, Alison M; Arnott, Shelley E

    2007-06-01

    Anthropogenic habitat disturbance can often lead to rapid evolution of environmental tolerances in taxa that are able to withstand the stressor. What we do not understand, however, is how species respond when the stressor no longer exists, especially across landscapes and over a considerable length of time. Once anthropogenic disturbance is removed and if there is an ecological trade-off associated with local adaptation to such an historical stressor, then evolutionary theory would predict evolutionary reversals. On the Boreal Shield, tens of thousands of lakes acidified as a result of SO2 emissions, but many of these lakes are undergoing chemical recovery as a consequence of reduced emissions. We investigated the adaptive consequences of disturbance and recovery to zooplankton living in these lakes by asking (1) if contemporary evolution of acid tolerance had arisen among Leptodiaptomus minutus copepod populations in multiple circum-neutral lakes with and without historical acidification, (2) if L. minutus populations were adaptively responding to reversals in selection in historically acidified lakes that had recovered to pH 6.0 for at least 6-8 years, and (3) if there was a fitness trade-off for L. minutus individuals with high acid tolerance at circum-neutral pH. L. minutus populations had higher acid tolerances in circum-neutral lakes with a history of acidification than in local and distant lakes that were never acidified. However, copepods in circum-neutral acid-recovering lakes were less acid-tolerant than were copepods in lakes with longer recovery time. This adaptive reversal in acid tolerance of L. minutus populations following lake recovery was supported by the results of a laboratory experiment that indicated a fitness trade-off in copepods with high acid tolerances at circum-neutral pH. These responses appear to have a genetic basis and suggest that L. minutus is highly adaptive to changes in environmental conditions. Therefore, restoration managers

  6. Coordination geometry of monomeric, dimeric and polymeric organotin(IV) compounds constructed from 5-bromopyridine-2-carboxylic acid and mono-, di- or tri-organotin precursors

    NASA Astrophysics Data System (ADS)

    Hong, Min; Yin, Han-Dong; Zhang, Yan-Wei; Jiang, Jin; Li, Chuan

    2013-03-01

    Reactions of mono-, di-, tri-alkyltin chlorides or oxide with 5-bromopyridine-2-carboxylic acid result in five new organotin(IV) compounds, [MeSn(O2CC5NH3Br)Cl2(H2O)]·(C2H5)2O (1), [(n-Bu)Sn(O2CC5NH3Br)Cl2(H2O)]·(C2H5)2O (2), {[(n-Bu)2Sn(O2CC5NH3Br)]2O}2 (3) [(n-Bu)3Sn(O2CC5NH3Br)]n (4) and [Ph3Sn(O2CC5NH3Br)]n (5), which have been characterized by single crystal X-ray diffraction, element analysis, IR, 1H, 13C and 119Sn NMR. Three different coordination modes for the ligand are demonstrated in this group of compounds: (1) bidentate mode with the pyridyl nitrogen atom and carboxyl oxygen atom for mono-alkyltin compounds 1 and 2, in which six-coordinated tin center is also bound with two chlorine ions and one water molecule; (2) compound 3 is a tetranuclear centrosymmetric dimer with a central Sn2O2 four-membered ring. The four tin atoms are linked by two bridging carboxyl groups while the remaining two act as monodentate ligands to the endo- and exo-cyclic tin atoms; (3) for tri-alkyltin compounds 4 and 5, the bidentate bridging carboxylic group coordinates with two different tin atoms through the Snsbnd Osbnd Cdbnd O → Sn bond, and the carboxylate bridge propagates 1D polymeric chains, typical for five coordinate tin. However, in compounds 3-5, the pyridyl nitrogen atoms do not participate in the coordination. For triorganotin(IV) polymers 4 and 5, the solution studies show the collapse of the intermolecular interactions observed in the solid state to yield monomeric species.

  7. Polymethylene-interrupted fatty acids: Biomarkers for native and exotic mussels in the Laurentian Great Lakes

    USGS Publications Warehouse

    Mezek, Tadej; Sverko, Ed; Ruddy, Martina D.; Zaruk, Donna; Capretta, Alfredo; Hebert, Craig E.; Fisk, Aaron T.; McGoldrick, Daryl J.; Newton, Teresa J.; Sutton, Trent M.; Koops, Marten A.; Muir, Andrew M.; Johnson, Timothy B.; Ebener, Mark P.; Arts, Michael T.

    2011-01-01

    Freshwater organisms synthesize a wide variety of fatty acids (FAs); however, the ability to synthesize and/or subsequently modify a particular FA is not universal, making it possible to use certain FAs as biomarkers. Herein we document the occurrence of unusual FAs (polymethylene-interrupted fatty acids; PMI-FAs) in select freshwater organisms in the Laurentian Great Lakes. We did not detect PMI-FAs in: (a) natural seston from Lake Erie and Hamilton Harbor (Lake Ontario), (b) various species of laboratory-cultured algae including a green alga (Scenedesmus obliquus), two cyanobacteria (Aphanizomenon flos-aquae and Synechococystis sp.), two diatoms (Asterionella formosa, Diatoma elongatum) and a chrysophyte (Dinobryon cylindricum) or, (c) zooplankton (Daphnia spp., calanoid or cyclopoid copepods) from Lake Ontario, suggesting that PMI-FAs are not substantively incorporated into consumers at the phytoplankton–zooplankton interface. However, these unusual FAs comprised 4-6% of total fatty acids (on a dry tissue weight basis) of native fat mucket (Lampsilis siliquoidea) and plain pocketbook (L. cardium) mussels and in invasive zebra (Dreissena polymorpha) and quagga (D. bugensis) mussels. We were able to clearly partition Great Lakes' mussels into three separate groups (zebra, quagga, and native mussels) based solely on their PMI-FA profiles. We also provide evidence for the trophic transfer of PMI-FAs from mussels to various fishes in Lakes Ontario and Michigan, further underlining the potential usefulness of PMI-FAs for tracking the dietary contribution of mollusks in food web and contaminant-fate studies.

  8. Acid-catalyzed conversion of mono- and poly-sugars into platform chemicals: effects of molecular structure of sugar substrate.

    PubMed

    Hu, Xun; Wu, Liping; Wang, Yi; Song, Yao; Mourant, Daniel; Gunawan, Richard; Gholizadeh, Mortaza; Li, Chun-Zhu

    2013-04-01

    Hydrolysis/pyrolysis of lignocellulosic biomass always produces a mixture of sugars with distinct structures as intermediates or products. This study tried to elucidate the effects of molecular structure of sugars on their acid-catalyzed conversions in ethanol/water. Location of carbonyl group in sugars (fructose versus glucose) and steric configuration of hydroxyl groups (glucose versus galactose) significantly affected yields of levulinic acid/ester (fructose>glucose>galactose). The dehydration of fructose to 5-(hydroxymethyl)furfural produces much less soluble polymer than that from glucose and galactose, which results in high yields of levulinic acid/ester from fructose. Anhydrate sugar such as levoglucosan tends to undergo the undesirable decomposition to form less levulinic acid/ester. Catalytic behaviors of the poly-sugars (sucrose, maltose, raffinose, β-cyclodextrins) were determined much by their basic units. However, their big molecular sizes create the steric hindrance that significantly affects their followed conversion over solid acid catalyst.

  9. Authigenic phyllosilicates in modern acid saline lake sediments and implications for Mars

    NASA Astrophysics Data System (ADS)

    Story, Stacy; Bowen, Brenda Beitler; Benison, Kathleen Counter; Schulze, Darrell G.

    2010-12-01

    Aluminum- and Fe/Mg-phyllosilicates are considered important geochemical indicators in terrestrial and Martian sedimentary systems. Traditionally, Al-phyllosilicates are characterized as forming and remaining stable under conditions of low to moderate pH, while Fe/Mg-phyllosilicates are considered representative of only dilute and moderate to high pH conditions. However, we have observed Al- and Fe/Mg-phyllosilicates in acid saline lake sediments in Western Australia. Phyllosilicate formation mechanisms in these lake systems include direct precipitation from lake waters, early diagenetic precipitation from shallow groundwaters, and deposition/alteration of detrital grains. X-ray diffraction analysis of silt- and clay-size sediments from two acid saline lakes in Western Australia indicates the presence of several complex mineral assemblages with extreme spatial heterogeneity that reflects the complex geochemistry of these lakes. These assemblages include unique combinations of authigenic and/or detrital phyllosilicates (e.g., kaolinite, smectite, and palygorskite-sepiolite), sulfates (e.g., alunite, jarosite, and gypsum), Fe-oxides (e.g., hematite and goethite), and other silicates (e.g., mullite and heulandite-clinoptilolite). Observations of Fe/Mg-phyllosilicates found in acid saline sediments in southern Western Australia suggest their degradation under conditions of low pH (2.5-5.4) is slowed by the high salinity (5-25%) of the lake and shallow groundwaters. The occurrence of both Al- and Fe/Mg-phyllosilicates in these acid saline lake sediments suggests that environmental interpretations based on the occurrence of phyllosilicates require additional consideration of their spatial distribution and association with other minerals. Moreover, the similarity between the diverse mineral assemblages in these terrestrial acid saline systems and those on Mars indicates similar conditions may have existed on Mars.

  10. Variation in Lake Michigan alewife (Alosa pseudoharengus) thiaminase and fatty acids composition

    USGS Publications Warehouse

    Honeyfield, D.C.; Tillitt, D.E.; Fitzsimons, J.D.; Brown, S.B.

    2010-01-01

    Thiaminase activity of alewife (Alosa pseudoharengus) is variable across Lake Michigan, yet factors that contribute to the variability in alewife thiaminase activity are unknown. The fatty acid content of Lake Michigan alewife has not been previously reported. Analysis of 53 Lake Michigan alewives found a positive correlation between thiaminase activity and the following fatty acid: C22:ln9, sum of omega-6 fatty acids (Sw6), and sum of the polyunsaturated fatty acids. Thiaminase activity was negatively correlated with C15:0, C16:0, C17:0, C18:0, C20:0, C22:0, C24:0, C18:ln9t, C20:3n3, C22:2, and the sum of all saturated fatty acids (SAFA). Multi-variant regression analysis resulted in three variables (C18:ln9t, Sw6, SAFA) that explained 71% (R2=0.71, P<0.0001) of the variation in thiaminase activity. Because the fatty acid content of an organism is related is food source, diet may be an important factor modulating alewife thiaminase activity. These data suggest there is an association between fatty acids and thiaminase activity in Lake Michigan alewife.

  11. Multiple-path dissociation mechanism for mono- and dinuclear tris(hydroxamato)iron(III) complexes with dihydroxamic acid ligands in aqueous solution.

    PubMed

    Boukhalfa, H; Crumbliss, A L

    2000-09-18

    Linear synthetic dihydroxamic acids ([CH3N(OH)C=O)]2(CH2)n; H2Ln) with short (n = 2) and long (n = 8) hydrocarbon-connecting chains form mono- and dinuclear complexes with Fe(III) in aqueous solution. At conditions where the formation of Fe2(Ln)3 is favored, complexes with each of the two ligand systems undergo [H+]-induced ligand dissociation processes via multiple sequential and parallel paths, some of which are common and some of which are different for the two ligands. The pH jump induced ligand dissociation proceeds in two major stages (I and II) where each stage is shown to be comprised of multiple components (Ix, where x = 1-3 for L2 and L8, and IIy, where y = 1-3 for L2 and y = 1-4 for L8). A reaction scheme consistent with kinetic and independent ESI-MS data is proposed that includes the tris-chelated complexes (coordinated H2O omitted for clarity) (Fe2(Ln)3, Fe2(L2)2(L2H)2, Fe(LnH)3, Fe(L8)(L8H)), bis-chelated complexes (Fe2(Ln)2(2+), Fe(LnH)2+, Fe(L8)+), and monochelated complexes (Fe(LnH)2+). Analysis of kinetic data for ligand dissociation from Fe2(Ln)(LnH)3+ (n = 2, 4, 6, 8) allows us to estimate the dielectric constant at the reactive dinuclear Fe(III) site. The existence of multiple ligand dissociation paths for the dihydroxamic acid complexes of Fe(III) is a feature that distinguishes these systems from their bidentate monohydroxamic acid and hexadentate trihydroxamic acid counterparts and may be a reason for the biosynthesis of dihydroxamic acid siderophores, despite higher environmental molar concentrations necessary to completely chelate Fe(III).

  12. Seven hexamethylenetetramine (HMTA) complexes with mono- and dicarboxylic acids: analysis of packing modes of HMTA complexes in the literature.

    PubMed

    Lemmerer, Andreas

    2011-04-01

    The crystal structures of seven hexamethylenetetramine (HMTA) complexes, or co-crystals, with carboxylic acid donor molecules are reported to explain the link between the molecular structure of HMTA and the crystal structure of the co-crystals, i.e. the dimension and shape of their hydrogen-bonded assembly. A comprehensive and detailed literature survey of HMTA complexes (38), be they neutral co-crystals or salts, with molecules containing carboxylic acid and phenol functional groups reveals that in general two N acceptors are used for strong O-H···N interactions. Owing to the relative arrangement of two of the four N atoms, the most common type of assembly features one-dimensional zigzag chains. Weak interactions of the C-H···N type are formed by N atoms not involved in strong interactions. These chains also form the basis of two-dimensional assemblies. These one- and two-dimensional assemblies feature either two or three functional groups. If only one functional group is on the donor molecule, then wing or V-shaped zero-dimensional assemblies are formed, which can be considered to be the building blocks for one- and two-dimensional assemblies. In general, the HMTA molecules form two-dimensional layers which are stabilized by weak hydrogen bonds. Co-crystals with cyclohexylcarboxylic acid (I), 4-fluorobenzoic acid (II), 4-methylbenzoic acid (III) and cinnamic acid (IV) all feature the V-shaped zero-dimensional assemblies. Co-crystals with cis-1,4-cyclohexyldicarboxylic acid (VI) and trans-1,4-cyclohexylcarboxylic acid (VII) feature the zigzag chains and can be structurally derived from co-crystal (I). Co-crystal (V), with 4-nitrobenzoic acid, has solvent water included and features hydrogen bonding to all four N atoms of the HMTA molecule.

  13. Chemical and biological status of lakes and streams in the upper midwest: assessment of acidic deposition effects

    USGS Publications Warehouse

    Wiener, J.G.; Eilers, J.M.

    1987-01-01

    Many lakes in three areas in the Upper Midwest - northeastern Minnesota, northern Wisconsin, and the Upper Peninsula of Michigan - have low acid neutralizing capacity (ANC) and may be susceptible to change by acidic deposition. Northcentral Wisconsin and the Upper Peninsula of Michigan together contain about 150-300 acidic lakes (ANC ≤ 0), whereas none have been found in Minnesota. These acidic lakes are precipitation-dominated, Clearwater seepage lakes having small surface area, shallow depth, and low concentrations of dissolved organic carbon. The spatial distribution of these acidic lakes parallels a west to east gradient of increasing sulfate and hydrogen ion deposition. Several of these acidic lakes exhibit chemical characteristics and biological changes consistent with those observed elsewhere in waters reported to be acidified by acidic deposition. However, an hypothesis of recent lake acidification is not supported by analyses of either historical chemical data or diatom remains in lake sediments, and natural sources of acidity and alternative ecological processes have not been conclusively eliminated as causative factors. Streams in this three-state region have high ANC and appear to be insensitive to acidic deposition. The species richness and composition of lacustrine fish communities in the region are partly related to pH and associated chemical factors. Sport fishes considered acid-sensitive and of primary concern with regard to acidification include walleye, smallmouth bass, and black crappie. The fishery in at least one lake, Morgan Lake in Wisconsin (pH 4.6), may have declined because of acidification. Given the general lack of quantitative fishery data for acidic Wisconsin and Michigan lakes, however, more general conclusions concerning impacts or the absence of impacts of acidification on the region's fishery resources are not possible.

  14. Response of fish assemblages to declining acidic deposition in Adirondack Mountain lakes, 1984-2012

    NASA Astrophysics Data System (ADS)

    Baldigo, B. P.; Roy, K. M.; Driscoll, C. T.

    2016-12-01

    Adverse effects of acidic deposition on the chemistry and fish communities were evident in Adirondack Mountain lakes during the 1980s and 1990s. Fish assemblages and water chemistry in 43 Adirondack Long-Term Monitoring (ALTM) lakes were sampled by the Adirondack Lakes Survey Corporation and the New York State Department of Environmental Conservation during three periods (1984-87, 1994-2005, and 2008-12) to document regional impacts and potential biological recovery associated with the 1990 amendments to the 1963 Clean Air Act (CAA). We assessed standardized data from 43 lakes sampled during the three periods to quantify the response of fish-community richness, total fish abundance, and brook trout (Salvelinus fontinalis) abundance to declining acidity that resulted from changes in U.S. air-quality management between 1984 and 2012. During the 28-year period, mean acid neutralizing capacity (ANC) increased significantly from 3 to 30 μeq/L and mean inorganic monomeric Al concentrations decreased significantly from 2.22 to 0.66 μmol/L, yet mean species richness, all species or total catch per net night (CPNN), and brook trout CPNN did not change significantly in the 43 lakes. Regression analyses indicate that fishery metrics were not directly related to the degree of chemical recovery and that brook trout CPNN may actually have declined with increasing ANC. While the richness of fish communities increased with increasing ANC as anticipated in several Adirondack lakes, observed improvements in water quality associated with the CAA have generally failed to produce detectable shifts in fish assemblages within a large number of ALTM lakes. Additional time may simply be needed for biological recovery to progress, or else more proactive efforts may be necessary to restore natural fish assemblages in Adirondack lakes in which water chemistry is steadily recovering from acidification.

  15. Response of fish assemblages to declining acidic deposition in Adirondack Mountain lakes, 1984–2012

    USGS Publications Warehouse

    Baldigo, Barry P.; Roy, Karen; Driscoll, Charles T.

    2016-01-01

    Adverse effects of acidic deposition on the chemistry and fish communities were evident in Adirondack Mountain lakes during the 1980s and 1990s. Fish assemblages and water chemistry in 43 Adirondack Long-Term Monitoring (ALTM) lakes were sampled by the Adirondack Lakes Survey Corporation and the New York State Department of Environmental Conservation during three periods (1984–87, 1994–2005, and 2008–12) to document regional impacts and potential biological recovery associated with the 1990 amendments to the 1963 Clean Air Act (CAA). We assessed standardized data from 43 lakes sampled during the three periods to quantify the response of fish-community richness, total fish abundance, and brook trout (Salvelinus fontinalis) abundance to declining acidity that resulted from changes in U.S. air-quality management between 1984 and 2012. During the 28-year period, mean acid neutralizing capacity (ANC) increased significantly from 3 to 30 μeq/L and mean inorganic monomeric Al concentrations decreased significantly from 2.22 to 0.66 μmol/L, yet mean species richness, all species or total catch per net night (CPNN), and brook trout CPNN did not change significantly in the 43 lakes. Regression analyses indicate that fishery metrics were not directly related to the degree of chemical recovery and that brook trout CPNN may actually have declined with increasing ANC. While the richness of fish communities increased with increasing ANC as anticipated in several Adirondack lakes, observed improvements in water quality associated with the CAA have generally failed to produce detectable shifts in fish assemblages within a large number of ALTM lakes. Additional time may simply be needed for biological recovery to progress, or else more proactive efforts may be necessary to restore natural fish assemblages in Adirondack lakes in which water chemistry is steadily recovering from acidification.

  16. Brown trout exposed to acid-treated and nontreated humic water from Lake Skjervatjern

    SciTech Connect

    Lien, L. )

    1994-01-01

    Lake Skjervatjern was divided into two separate basins. One basin and its catchment were treated with sulphuric acid and ammonium nitrate. The other part was kept as a control. Brown trout was exposed to acid-treated and nontreated water from the outlets of the basins. The results showed higher mortality in acid-treated water compared to nontreated water from Lake Skjervatjern. Chloride concentration in blood plasma was lower in fish exposed to acid-treated water, indicating a higher degree of stress. Some physical/chemical parameters showed different values for the acid-treated basin compared to water from the nontreated one, e.g., increasing concentrations of sulphur and nitrogen were seen in the acid-treated basin. However, no physical/chemical parameter or group of parameters has been identified from the two basins that can explain the difference in fish mortality and stress. 6 refs., 1 fig., 3 tabs.

  17. Integrated Lake-Watershed Acidification Study (ILWAS): contributions to the international conference on the ecological impact of acid precipitation

    SciTech Connect

    Not Available

    1981-05-01

    The Integrated Lake-Watershed Acidification Study (ILWAS) was initiated to study and detail lake acidification processes for three lake watershed basins in the Adirondack Park region of New York. The three basins (Woods, Sagamore, and Panther), receive similar amounts of acid deposition yet observable pH values for the lakes are very dissimilar indicating unequal acid neutralizing capacities among the watersheds. This volume contains a compilation of seven papers. Relevant topics include: a characterization of the geology, hydrology, limnology and vegetation of the three study sites, an analysis of acid precipitation quality and quantity, the effects of vegetative canopy, the effects of snowmelt, the effects of winter lake stratification, comparison of heavy metal transport, examination of acidic sources other than direct precipitation, assessment of lake acidification during spring thaw and integration of all acidification components with a mathematical model.

  18. Comparative study of mono- and multi-filament MgB2 wires with different boron powders and malic acid addition

    NASA Astrophysics Data System (ADS)

    Kim, J. H.; Heo, Yoon-Uk; Matsumoto, A.; Kumakura, H.; Rindfleisch, M.; Tomsic, M.; Dou, S. X.

    2010-07-01

    We evaluated the effects of different boron (B) powders and of malic acid (C4H6O5) addition on the critical current density (Jc) of mono- and multi-filament MgB2 wires. We found that Jc of the wires made from the amorphous B showed the best performance. Low sintering processing keeps the grain size small, which leads to strong flux pinning. From transmission electron microscopy (TEM) observations, we confirmed that the crystalline B powders supplied by SMI and Tangshan had a β-rhombohedral structure as a main phase. These two powders also had numerous defects, such as twin and stacking faults inside the powder particles. However, these defects are not enough to promote the full reaction between magnesium (Mg) and B crystalline powder when sintered at low temperatures, and brings about low Jc values. Even though the morphologies of the two crystalline B powders appeared somewhat different, Jc for the two wires had similar quantitative values. For the malic acid doped wires, Jc of the wire made from the amorphous B was estimated to be above 100 000 A cm - 2 at 6 T and 4.2 K. This value is comparable to the low temperature superconductor Nb-Ti. In addition, the Jc was 25 000 A cm - 2 at 10 T and 4.2 K. This performance is the best Jc reported so far in in situ processed MgB2 wires. Interestingly, the low-field Jc performance of malic acid doped wire fabricated with crystalline B is higher than that of the pure wire fabricated with amorphous B. At 20 K, enhanced performance of Jc by malic acid doping is much higher than that of the pure MgB2 wire. The Jc at 5 T and 20 K was estimated to be 13 000 A cm - 2.

  19. Chemical composition of softwater Florida lakes and their sensitivity to acid precipitation

    SciTech Connect

    Hendry, C.D.; Brezonik, P.L.

    1984-02-01

    Based on alkalinity data for 596 lakes, 31 percent of Florida's 7300 lakes have < 100 ..mu..eq/L alkalinity and are sensitive to acid deposition. More than two-thirds of the lakes in 12 northern Florida counties fit this criterion. Increasing aluminum and decreasing nutrient and chlorophyll a concentrations were observed with decreasing pH in a survey of 20 softwater lakes. Maximum measured aluminum values (100-150 ..mu..g/L) are below levels associated with fish toxicity. Factor analysis showed that lake chemistry was related to three principal factors, representing three major processes: watershed weathering, acidification, and nutrient inputs. An acidification index defined as the difference between excess SO/sub 4//sup 2 -/ and excess (Ca/sup 2 +/ + Mg/sup 2 +/) accounted for 74 percent of the variance in lake pH. Comparison of historical (late 1950s) and present data for pH, alkalinity, and excess SO/sub 4//sup 2 -/ indicated loss of alkalinity (> 25 ..mu..eq/L) and increases in excess SO/sub 4//sup 2 -/ (16-34 ..mu..eq/L) in several softwater lakes.

  20. Hematite-Based Solar Water Splitting in Acidic Solutions: Functionalization by Mono- and Multilayers of Iridium Oxygen-Evolution Catalysts.

    PubMed

    Li, Wei; Sheehan, Stafford W; He, Da; He, Yumin; Yao, Xiahui; Grimm, Ronald L; Brudvig, Gary W; Wang, Dunwei

    2015-09-21

    Solar water splitting in acidic solutions has important technological implications, but has not been demonstrated to date in a dual absorber photoelectrochemical cell. The lack of functionally stable water-oxidation catalysts (WOCs) in acids is a key reason for this slow development. The only WOCs that are stable at low pH are Ir-based systems, which are typically too expensive to be implemented broadly. It is now shown that this deficiency may be corrected by applying an ultra-thin monolayer of a molecular Ir WOC to hematite for solar water splitting in acidic solutions. The turn-on voltage is observed to shift cathodically by 250 mV upon the application of a monolayer of the molecular Ir WOC. When the molecular WOC is replaced by a heterogeneous multilayer derivative, stable solar water splitting for over 5 h is achieved with near-unity Faradaic efficiency.

  1. Pt based nanocomposites (mono/bi/tri-metallic) decorated using different carbon supports for methanol electro-oxidation in acidic and basic media.

    PubMed

    Singh, Baljit; Murad, Lukaa; Laffir, Fathima; Dickinson, Calum; Dempsey, Eithne

    2011-08-01

    Pt based mono/bi/tri-metallic nanocomposites on different carbon based supports (activated carbon (AC), carbon nanotubes (CNTs) and carbon nanofibers (CNFs)) were synthesised and Pt surface enrichment achieved. The overall theoretical metallic content (Pt + Au + Sn) was 20% (w/w) in all mono/bi/tri-metallic nanocomposites and was found to be uniformly distributed in the supporting matrix (80%). The surface morphology and composition of the synthesised materials was characterised using scanning electron microscopy (SEM), energy-dispersive X-ray spectrometry (EDX), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), thermo-gravimetric analysis (TGA), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS), while cyclic voltammetry was employed in order to confirm their typical metallic electrochemical characteristics. Electrochemical measurements indicated that Pt(2)Au(1)Sn(1) trimetallic catalysts demonstrated a significantly higher electrochemically active surface area relative to activated carbon supported PtAu based bimetallic counterparts. The results show that the CNT based trimetallic catalyst (Pt(2)Au(1)Sn(1)/CNT) showed greatest electroactive surface area (49.3 m(2)/g) and current density for methanol oxidation in acidic (490 mA mg(-1) Pt) as well as basic (1700 mA mg(-1) Pt) conditions. Results demonstrated that in comparison to Au/C and Sn/C (no/negligible response), the presence of a small amount of Pt in the Au and Sn based nanocomposites, significantly modified the catalytic properties. The activated carbon supported bimetallic (Pt(1)Au(3)/C) catalyst showed reasonably good response (260 mA mg(-1) Pt) among all bimetallic nanomaterials examined. The current response achieved for Pt(2)Au(1)Sn(1)/CNT was 1.9 times (in acidic media) and 2.1 times (in basic media) that for synthesised Pt/C in terms of per mg Pt activity. Overall the methanol oxidation studies demonstrated that the presence of Au and Sn in Pt

  2. The organic content of the Tagish Lake meteorite.

    PubMed

    Pizzarello, S; Huang, Y; Becker, L; Poreda, R J; Nieman, R A; Cooper, G; Williams, M

    2001-09-21

    The Tagish Lake meteorite fell last year on a frozen lake in Canada and may provide the most pristine material of its kind. Analyses have now shown this carbonaceous chondrite to contain a suite of soluble organic compounds (approximately 100 parts per million) that includes mono- and dicarboxylic acids, dicarboximides, pyridine carboxylic acids, a sulfonic acid, and both aliphatic and aromatic hydrocarbons. The insoluble carbon exhibits exclusive aromatic character, deuterium enrichment, and fullerenes containing "planetary" helium and argon. The findings provide insight into an outcome of early solar chemical evolution that differs from any seen so far in meteorites.

  3. Lake eutrophication and brownification downgrade availability and transfer of essential fatty acids for human consumption.

    PubMed

    Taipale, S J; Vuorio, K; Strandberg, U; Kahilainen, K K; Järvinen, M; Hiltunen, M; Peltomaa, E; Kankaala, P

    2016-11-01

    Fish are an important source of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) for birds, mammals and humans. In aquatic food webs, these highly unsaturated fatty acids (HUFA) are essential for many physiological processes and mainly synthetized by distinct phytoplankton taxa. Consumers at different trophic levels obtain essential fatty acids from their diet because they cannot produce these sufficiently de novo. Here, we evaluated how the increase in phosphorus concentration (eutrophication) or terrestrial organic matter inputs (brownification) change EPA and DHA content in the phytoplankton. Then, we evaluated whether these changes can be seen in the EPA and DHA content of piscivorous European perch (Perca fluviatilis), which is a widely distributed species and commonly consumed by humans. Data from 713 lakes showed statistically significant differences in the abundance of EPA- and DHA-synthesizing phytoplankton as well as in the concentrations and content of these essential fatty acids among oligo-mesotrophic, eutrophic and dystrophic lakes. The EPA and DHA content of phytoplankton biomass (mgHUFAg(-1)) was significantly lower in the eutrophic lakes than in the oligo-mesotrophic or dystrophic lakes. We found a strong significant correlation between the DHA content in the muscle of piscivorous perch and phytoplankton DHA content (r=0.85) as well with the contribution of DHA-synthesizing phytoplankton taxa (r=0.83). Among all DHA-synthesizing phytoplankton this correlation was the strongest with the dinoflagellates (r=0.74) and chrysophytes (r=0.70). Accordingly, the EPA+DHA content of perch muscle decreased with increasing total phosphorus (r(2)=0.80) and dissolved organic carbon concentration (r(2)=0.83) in the lakes. Our results suggest that although eutrophication generally increase biomass production across different trophic levels, the high proportion of low-quality primary producers reduce EPA and DHA content in the food web up to predatory fish

  4. Response of sediment calcium and magnesium species to the regional acid deposition in eutrophic Taihu Lake, China.

    PubMed

    Tao, Yu; Dan, Dai; Chengda, He; Qiujin, Xu; Fengchang, Wu

    2016-11-01

    Acid deposition causes carbonate dissolution in watersheds and leads to profound impacts on water chemistry of lakes. Here, we presented a detailed study on the seasonal, spatial, and vertical variations of calcium and magnesium species in the overlying water, interstitial water, and sediment profiles in eutrophic Taihu Lake under the circumstance of regional acid deposition. The result showed that both the acid deposition and biomineralization in Taihu Lake had effects on Ca and Mg species. In the lake water, calcium carbonate was saturated or over-saturated based on long-term statistical calculation of the saturation index (SI). On the sediment profiles, significant difference in Ca and Mg species existed between the surface sediment (0-10 cm) and deeper sediments (>10 cm). The interstitial water Ca(2+) and Mg(2+), ion-exchangeable Ca and Mg in the surface sediment were higher than those in the deeper sediment. In the spring, when the acid deposition is more intensive, the acid-extracted Ca and Mg in the surface sediment were lower than that in the deeper sediment in the northwest lake, due to carbonate dissolution caused by the regional acid deposition. Spatially, the higher concentration of acid-extracted Ca and Mg in the northwest surface sediment than that in the east lake was observed, indicating the pronounced carbonate biomineralization by algae bloom in the northwest lake. Statistical analysis showed that acid deposition exerted a stronger impact on the variation of acid-extracted Ca and Mg in the surface sediment than the biomineralization in Taihu Lake. For the total Ca and Mg concentration in the spring, however, no significant change between the surface and deeper sediment in the northwest lake was observed, indicating that the carbonate precipitation via biomineralization and the carbonate dissolution due to acidic deposition were in a dynamic balance. These features are of major importance for the understanding of combined effects of acid

  5. Spatial characterization of acid rain stress in Canadian Shield Lakes

    NASA Technical Reports Server (NTRS)

    Tanis, Fred J.

    1987-01-01

    An analysis was performed to interpret the spatial aspects of lake acidification. Three types of relationships were investigated based upon the August to May seasonal scene pairing. In the first type of analysis ANOVA was used to examine the mean Thematic Mapper band one count by ecophysical strata. The primary difference in the two ecophysical strata is the soil type and depth over the underlying bedrock. Examination of the August to May difference values for TM band one produced similar results. Group A and B strata were the same as above. The third type of analysis examined the relationship between values of the August to May difference from polygons which have similar ecophysical properties with the exception of sulfate deposition. For this case lakes were selected from units with sandy soils over granitic rock types and the sulfate deposition was 1.5 or 2.5 g/sq m/yr.

  6. Reactions of CO2 with aqueous piperazine solutions: formation and decomposition of mono- and dicarbamic acids/carbamates of piperazine at 25.0 °C.

    PubMed

    Conway, William; Fernandes, Debra; Beyad, Yaser; Burns, Robert; Lawrance, Geoffrey; Puxty, Graeme; Maeder, Marcel

    2013-02-07

    Piperazine (PZ) is widely recognized as a promising solvent for postcombustion capture (PCC) of carbon dioxide (CO(2)). In view of the highly conflicting data describing the kinetic reactions of CO(2)(aq) in piperazine solutions, the present study focuses on the identification of the chemical mechanism, specifically the kinetic pathways for CO(2)(aq) in piperazine solutions that form the mono- and dicarbamates, using the analysis of stopped-flow spectrophotometric kinetic measurements and (1)H NMR spectroscopic data at 25.0 °C. The complete set of rate and equilibrium constants for the kinetic pathways, including estimations for the protonation constants of the suite of piperazine carbamates/carbamic acids, is reported here using an extended kinetic model which incorporates all possible reactions for CO(2)(aq) in piperazine solutions. From the kinetic data determined in the present study, the reaction of CO(2)(aq) with free PZ was found to be the dominant reactive pathway. The superior reactivity of piperazine is confirmed in the kinetic rate constant determined for the formation of piperazine monocarbamic acid (k(7) = 2.43(3) × 10(4) M(-1) s(-1)), which is within the wide range of published values, making it one of the faster reacting amines. The corresponding equilibrium constant for the formation of the monocarbamic acid, K(7), markedly exceeds that of other monoamines. Kinetic and equilibrium constants for the remaining pathways indicate a minor contribution to the overall kinetics at high pH; however, these pathways may become more significant at higher CO(2) loadings and lower pH values where the concentrations of the reactive species are correspondingly higher.

  7. A mechanistic study into the epoxidation of carboxylic acid and alkene in a mono, di-acylglycerol lipase.

    PubMed

    Wang, Xuping; Tang, Qingyun; Popowicz, Grzegorz Maria; Yang, Bo; Wang, Yonghua

    2015-05-01

    More and more industrial chemistry reactions rely on green technologies. Enzymes are finding increasing use in diverse chemical processes. Epoxidized vegetable oils have recently found applications as plasticizers and additives for PVC production. We report here an unusual activity of the Malassezia globosa lipase (SMG1) that is able to catalyze epoxidation of alkenes. SMG1 catalyzes formation of peroxides from long chain carboxylic acids that subsequently react with double bonds of alkenes to produce epoxides. The SMG1 is selective towards carboxylic acids and active also as a mutant lacking hydrolase activity. Moreover we present previously unobserved mechanism of catalysis that does not rely on acyl-substrate complex nor tetrahedral intermediate. Since SMG1 lipase is activated by allosteric change upon binding to the lipophilic-hydrophilic phase interface we reason that it can be used to drive the epoxidation in the lipophilic phase exclusively.

  8. New mono- and dimeric members of the secalonic acid family: blennolides A-G isolated from the fungus Blennoria sp.

    PubMed

    Zhang, Wen; Krohn, Karsten; Flörke, Ulrich; Pescitelli, Gennaro; Di Bari, Lorenzo; Antus, Sándor; Kurtán, Tibor; Rheinheimer, Joachim; Draeger, Siegfried; Schulz, Barbara

    2008-01-01

    Blennolides A-G (2-8), seven unusual chromanones, were isolated together with secalonic acid B (1) from Blennoria sp., an endophytic fungus from Carpobrotus edulis. This is the first reported isolation of the blennolides 2 and 3 (hemisecalonic acids B and E), the existence of which as the monomeric units of the dimeric secalonic acids had long been postulated. A compound of the proposed structure 4 (beta-diversonolic ester) will need to be revised, as its reported data do not fit those of the established structure of blennolide C (4). Other monomers, the blennolides D-F (5-7) seem to be derived from blennolides A (2) and B (3) by rearrangement of the hydroaromatic ring. The heterodimer 8, composed of the monomeric blennolide A (2) and the rearranged 11-dehydroxy derivative of blennolide E (6), extends the ergochrome family with an ergoxanthin type of skeleton. The structures of the new compounds were elucidated by detailed spectroscopic analysis and further confirmed by an X-ray diffraction study of a single crystal of 2. The absolute configurations were determined by TDDFT calculations of CD spectra, including the solid-state CD/TDDFT approach. Preliminary studies showed strong antifungal and antibacterial activities of these compounds against Microbotryum violaceum and Bacillus megaterium, respectively. They were also active against the alga Chlorella fusca and the bacterium Escherichia coli.

  9. C-H bond strengths and acidities in aromatic systems: effects of nitrogen incorporation in mono-, di-, and triazines.

    PubMed

    Wren, Scott W; Vogelhuber, Kristen M; Garver, John M; Kato, Shuji; Sheps, Leonid; Bierbaum, Veronica M; Lineberger, W Carl

    2012-04-18

    The negative ion chemistry of five azine molecules has been investigated using the combined experimental techniques of negative ion photoelectron spectroscopy to obtain electron affinities (EA) and tandem flowing afterglow-selected ion tube (FA-SIFT) mass spectrometry to obtain deprotonation enthalpies (Δ(acid)H(298)). The measured Δ(acid)H(298) for the most acidic site of each azine species is combined with the EA of the corresponding radical in a thermochemical cycle to determine the corresponding C-H bond dissociation energy (BDE). The site-specific C-H BDE values of pyridine, 1,2-diazine, 1,3-diazine, 1,4-diazine, and 1,3,5-triazine are 110.4 ± 2.0, 111.3 ± 0.7, 113.4 ± 0.7, 107.5 ± 0.4, and 107.8 ± 0.7 kcal mol(-1), respectively. The application of complementary experimental methods, along with quantum chemical calculations, to a series of nitrogen-substituted azines sheds light on the influence of nitrogen atom substitution on the strength of C-H bonds in six-membered rings.

  10. Impacts on water quality and biota from natural acid rock drainage in Colorado's Lake Creek watershed

    USGS Publications Warehouse

    Bird, D.A.; Sares, Matthew A.; Policky, Greg A.; Schmidt, Travis S.; Church, Stanley E.

    2006-01-01

    Colorado's Lake Creek watershed hosts natural acid rock drainage that significantly impacts surface water, streambed sediment, and aquatic life. The source of the ARD is a group of iron-rich springs that emerge from intensely hydrothermally altered, unexploited, low-grade porphyry copper mineralization in the Grizzly Peak Caldera. Source water chemistry includes pH of 2.5 and dissolved metal concentrations of up to 277 mg/L aluminum, 498 mg/L iron, and 10 mg/L copper. From the hydrothermally altered area downstream for 27 kilometers to Twin Lakes Reservoir, metal concentrations in streambed sediment are elevated and the watershed experiences locally severe adverse impacts to aquatic life due to the acidic, metal-laden water. The water and sediment quality of Twin Lakes Reservoir is sufficiently improved that the reservoir supports a trout fishery, and remnants of upstream ARD are negligible.

  11. Cytotoxic Activity of Bioactive Compound 1, 2- Benzene Dicarboxylic Acid, Mono 2- Ethylhexyl Ester Extracted from a Marine Derived Streptomyces sp. VITSJK8.

    PubMed

    Krishnan, Kannabiran; Mani, Abirami; Jasmine, Subashini

    2014-01-01

    Marine Streptomyces are prolific producers of majority of bioactive secondary metabolites which are used in pharmaceutical industry as effective drugs against life threatening diseases. The cytotoxic activity of the pure compound 1, 2- benzene dicarboxylic acid, mono 2- ethylhexyl ester (DMEHE) from marine derived actinomycete Streptomyces sp. VITSJK8 was investigated against mouse embryonic fibroblast (NIH 3T3) and human keratinocyte (HaCaT) normal cell lines, human hepatocellular liver carcinoma (HepG 2) and human breast adenocarcinoma (MCF-7) cell lines by using MTT assay. The compound DMEHE exhibited IC 50 values of 42, 100, 250 and 500 µg/ ml against HepG2, MCF-7, HaCaT and NIH 3T3 cell lines, respectively. The effect of DMEHE on the growth of cancer cell lines was expressed as the % of viability. Cell viability was recorded as 67.7%, 78.14%, 82.23% and 96. 11% in HepG2, MCF-7, HaCaT and NIH 3T3 cells, respectively. The results of the study conclude that the bioactive compound isolated from the potential isolate Streptomyces sp. VITSJK8 exhibited cytotoxic activity against HepG2 and MCF- 7 cancer cell lines and low toxicity against normal HaCaT and NIH 3T3 cell lines.

  12. Cytotoxic Activity of Bioactive Compound 1, 2- Benzene Dicarboxylic Acid, Mono 2- Ethylhexyl Ester Extracted from a Marine Derived Streptomyces sp. VITSJK8

    PubMed Central

    Krishnan, Kannabiran; Mani, Abirami; Jasmine, Subashini

    2014-01-01

    Marine Streptomyces are prolific producers of majority of bioactive secondary metabolites which are used in pharmaceutical industry as effective drugs against life threatening diseases. The cytotoxic activity of the pure compound 1, 2- benzene dicarboxylic acid, mono 2- ethylhexyl ester (DMEHE) from marine derived actinomycete Streptomyces sp. VITSJK8 was investigated against mouse embryonic fibroblast (NIH 3T3) and human keratinocyte (HaCaT) normal cell lines, human hepatocellular liver carcinoma (HepG 2) and human breast adenocarcinoma (MCF-7) cell lines by using MTT assay. The compound DMEHE exhibited IC 50 values of 42, 100, 250 and 500 µg/ ml against HepG2, MCF-7, HaCaT and NIH 3T3 cell lines, respectively. The effect of DMEHE on the growth of cancer cell lines was expressed as the % of viability. Cell viability was recorded as 67.7%, 78.14%, 82.23% and 96. 11% in HepG2, MCF-7, HaCaT and NIH 3T3 cells, respectively. The results of the study conclude that the bioactive compound isolated from the potential isolate Streptomyces sp. VITSJK8 exhibited cytotoxic activity against HepG2 and MCF- 7 cancer cell lines and low toxicity against normal HaCaT and NIH 3T3 cell lines. PMID:25635251

  13. Hydrogen bonding in electronically excited states: a comparison between formic acid dimer and its mono-substituted thioderivatives.

    PubMed

    Cimas, Alvaro; Mó, Otilia; Yáñez, Manuel; Martín, Nazario; Corral, Inés

    2010-10-28

    A multi-state complete active space second order perturbation theory (MS-CASPT2) study on the valence singlet electronic excited states of formic acid dimer is presented. The electronic spectrum of this dihydrogen bonded system is dominated by nπ* and ππ* intramonomer and charge transfer excitations and consists of a very intense ππ* transition at 8.25 eV and three weaker nπ*(2×) and ππ*(1×) electronic excitations at 6.21 eV, 9.13 eV, and 9.93 eV, respectively. The characteristic nπ*-nπ*-ππ*-ππ*… pattern found in the formic acid dimer electronic spectrum is altered when a sulfur atom is introduced in the molecule. Furthermore, carbonyl-by-thiocarbonyl or hydroxyl-by-thiohydroxyl substitution is predicted to strongly affect the intensity of the above electronic transitions. The effect of oxygen-by-sulfur substitution on the geometry of the first excited state (S(1)) has been investigated at the CC2 and CASSCF levels of theory. Although the two methods qualitatively predict the same geometrical changes upon nπ* excitation, the geometries of the S(1) state are found to differ considerably between the two levels.

  14. Response of DOC in acid-sensitive Maine lakes to decreasing sulfur deposition (1993 - 2009)

    EPA Science Inventory

    In response to the Clean Air Act Amendments of 1990, sulfur deposition has decreased across the northeastern United States. As a result, sulfate concentrations in lakes and streams have also decreased and many surface waters have become less acidic. Over the same time period, th...

  15. Effects of salinity and ultraviolet radiation on the bioaccumulation of mycosporine-like amino acids in Artemia from Lake Urmia (Iran).

    PubMed

    Khosravi, Sanaz; Khodabandeh, Saber; Agh, Naser; Bakhtiarian, Mahdieh

    2013-01-01

    We investigated the effects of salinity and artificial UV radiation on the accumulation of mycosporine-like amino acids (MAAs) in sexual and parthenogenetic Artemia from Lake Urmia. The nauplii hatched from the cysts were cultured until adulthood under two salinities (150 and 250 g L(-1) ) and two light treatments (PAR and PAR+UVR) in the laboratory. Finally, the Artemia were analyzed for their concentration of MAAs. In most of the cases, the higher salinity level applied was found to increase the MAA concentrations in both Artemia populations significantly. The acquisition efficiency of MAAs in both Artemia populations increased under exposure to UVR-supplemented photosynthetically active radiation (PAR) compared to those raised under PAR, except for Porphyra-334. It was observed that combination of UV radiation and elevated salinity significantly increased the bioaccumulation of MAAs. Thus, the presence of these compounds in these populations of Artemia may increase their adaptability for living in high-UV and high-salinity conditions prevailing in Lake Urmia. Higher concentrations of MAAs in the parthenogenetic population of Artemia could be probably attributed to its mono sex nature and higher adaptation capacities to extreme environmental conditions.

  16. Mono and binuclear ruthenium(II) complexes containing 5-chlorothiophene-2-carboxylic acid ligands: Spectroscopic analysis and computational studies

    NASA Astrophysics Data System (ADS)

    Swarnalatha, Kalaiyar; Kamalesu, Subramaniam; Subramanian, Ramasamy

    2016-11-01

    New Ruthenium complexes I, II and III were synthesized using 5-chlorothiophene-2-carboxylic acid (5TPC), as ligand and the complexes were characterized by elemental analysis, FT-IR, 1H, 13C NMR, and mass spectroscopic techniques. Photophysical and electrochemical studies were carried out and the structures of the synthesized complex were optimized using density functional theory (DFT). The molecular geometry, the highest occupied molecular orbital (HOMO), the lowest unoccupied molecular orbital (LUMO) energies and Mulliken atomic charges of the molecules are determined at the B3LYP method and standard 6-311++G (d,p) basis set starting from optimized geometry. They possess excellent stabilities and their thermal decomposition temperatures are 185 °C, 180 °C and 200 °C respectively, indicating that the metal complexes are suitable for the fabrication processes of optoelectronic devices.

  17. Unveiling of novel regio-selective fatty acid double bond hydratases from Lactobacillus acidophilus involved in the selective oxyfunctionalization of mono- and di-hydroxy fatty acids.

    PubMed

    Kim, Kyoung-Rok; Oh, Hye-Jin; Park, Chul-Soon; Hong, Seung-Hye; Park, Ji-Young; Oh, Deok-Kun

    2015-11-01

    The aim of this study is the first time demonstration of cis-12 regio-selective linoleate double-bond hydratase. Hydroxylation of fatty acids, abundant feedstock in nature, is an emerging alternative route for many petroleum replaceable products thorough hydroxy fatty acids, carboxylic acids, and lactones. However, chemical route for selective hydroxylation is still quite challenging owing to low selectivity and many environmental concerns. Hydroxylation of fatty acids by hydroxy fatty acid forming enzymes is an important route for selective biocatalytic oxyfunctionalization of fatty acids. Therefore, novel fatty acid hydroxylation enzymes should be discovered. The two hydratase genes of Lactobacillus acidophilus were identified by genomic analysis, and the expressed two recombinant hydratases were identified as cis-9 and cis-12 double-bond selective linoleate hydratases by in vitro functional validation, including the identification of products and the determination of regio-selectivity, substrate specificity, and kinetic parameters. The two different linoleate hydratases were the involved enzymes in the 10,13-dihydroxyoctadecanoic acid biosynthesis. Linoleate 13-hydratase (LHT-13) selectively converted 10 mM linoleic acid to 13S-hydroxy-9(Z)-octadecenoic acid with high titer (8.1 mM) and yield (81%). Our study will expand knowledge for microbial fatty acid-hydroxylation enzymes and facilitate the designed production of the regio-selective hydroxy fatty acids for useful chemicals from polyunsaturated fatty acid feedstocks.

  18. Long term (1987-2012) trends in water chemistry of acid sensitive Swedish lakes

    NASA Astrophysics Data System (ADS)

    Futter, Martyn; Valinia, Salar; Fölster, Jens

    2014-05-01

    Acidification of surface waters is a serious concern in Sweden. During the 1970s and 1980s, many surface waters in Sweden were acidified by long-range pollution. Legislated emissions reductions have led to the recovery of many water bodies but today, there are concerns about the possibility of re-acidification. Sweden is committed to a goal of natural acidification only (i.e. no anthropogenic acidification). Here, we present long term (1987-2012) trends in strong acid anion, base cation, organic carbon and alkalinity measurements. Lakes are defined as acidified in Sweden if pH is more than 0.4 units less than a reference (1860) pH estimated using MAGIC, a widely used process-based model of acidification. Using this criteria, many acid sensitive Swedish lakes are still acidified. A changing climate and more intensive forest harvesting may further delay the recovery from acidification. Average measured alkalinity in the 38 lakes presented here was <= 0.02 mekv/l between 2000-2012. Strong acid anion concentrations declined, primarily as a result of declines in sulfate. Chloride is now the dominant anion in many of these lakes. Base cations concentrations have declined less rapidly, leading to an increase in charge balance ANC. This increase in charge balance ANC has not been matched by an increase in measured alkalinity. Total organic carbon concentrations have increased significantly in many of these lakes, to the point where modeled organic acidity is now approximately equal to inorganic acidity. While the results presented here conform to acidification theory, they illustrate the value of long-term monitoring for assessing the effects of pollutant reduction measures, identifying new threats to water quality and corroborating model results. Most importantly, the long-term monitoring results presented here can be an important tool for informing environmental policy.

  19. Significant seasonal variations of microbial community in an acid mine drainage lake in Anhui Province, China.

    PubMed

    Hao, Chunbo; Wei, Pengfei; Pei, Lixin; Du, Zerui; Zhang, Yi; Lu, Yanchun; Dong, Hailiang

    2017-04-01

    Acid mine drainage (AMD),characterized by strong acidity and high metal concentrations, generates from the oxidative dissolution of metal sulfides, and acidophiles can accelerate the process significantly. Despite extensive research in microbial diversity and community composition, little is known about seasonal variations of microbial community structure (especially micro eukaryotes) in response to environmental conditions in AMD ecosystem. To this end, AMD samples were collected from Nanshan AMD lake, Anhui Province, China, over a full seasonal cycle from 2013 to 2014, and water chemistry and microbial composition were studied. pH of lake water was stable (∼3.0) across the sampling period, while the concentrations of ions varied dramatically. The highest metal concentrations in the lake were found for Mg and Al, not commonly found Fe. Unexpectedly, ultrahigh concentration of chlorophyll a was measured in the extremely acidic lake, reaching 226.43-280.95 μg/L in winter, even higher than those in most eutrophic freshwater lakes. Both prokaryotic and eukaryotic communities showed a strong seasonal variation. Among the prokaryotes, "Ferrovum", a chemolithotrophic iron-oxidizing bacterium was predominant in most sampling seasons, although it was a minor member prior to September, 2012. Fe(2+) was the initial geochemical factor that drove the variation of the prokaryotic community. The eukaryotic community was simple but varied more drastically than the prokaryotic community. Photoautotrophic algae (primary producers) formed a food web with protozoa or flagellate (top consumers) across all four seasons, and temperature appeared to be responsible for the observed seasonal variation. Ochromonas and Chlamydomonas (responsible for high algal bloom in winter) occurred in autumn/summer and winter/spring seasons, respectively, because of their distinct growth temperatures. The closest phylogenetic relationship between Chlamydomonas species in the lake and those in Arctic

  20. Photomodulation of conformational states. I. Mono- and bicyclic peptides with (4-amino)phenylazobenzoic acid as backbone constituent.

    PubMed

    Renner, C; Behrendt, R; Spörlein, S; Wachtveitl, J; Moroder, L

    2000-12-01

    The thioredoxin reductase active-site fragment H-Ala-Cys-Ala-Thr-Cys-Asp-Gly-Phe-OH [134-141], which is known for its high tendency to assume an almost identical conformation as in the intact enzyme, was backbone cyclized with the photoresponsive (4-amino)phenylazobenzoic acid (APB) to produce a monocyclic and disulfide-bridged bicyclic APB-peptide. Light-induced reversible cis/trans isomerization occurs at identical extents in both the linear and the two cyclic forms. Nuclear magnetic resonance conformational analysis clearly revealed that in the bicyclic APB-peptide both as a trans- and cis-azo-isomer the constraints imparted by the bicyclic structure do not allow the molecule to relax into a defined low energy conformation, thus making the molecule a frustrated system that flip-flops between multiple conformational states. Conversely, the monocyclic APB peptide folds into a well-defined lowest energy structure as a trans-azo-isomer, which upon photoisomerization to the cis-azo configuration relaxes into a less restricted conformational space. First femtosecond spectroscopic analysis of the dynamics of the photoreaction confirm a fast first phase on the femtosecond time scale related to the cis/trans isomerization of the azobenzene moiety followed by a slower phase in the picosecond time scale that involves an adjustment of the peptide backbone. Due to the well- defined photoresponsive two-state transition of this monocyclic peptide molecule, it represents a model system well suited for studying the ultrafast dynamics of conformational transitions by time-resolved spectroscopy.

  1. Modeling aluminum-silicon chemistries and application to Australian acidic playa lakes as analogues for Mars

    USGS Publications Warehouse

    Marion, G.M.; Crowley, J.K.; Thomson, B.J.; Kargel, J.S.; Bridges, N.T.; Hook, S.J.; Baldridge, A.; Brown, A.J.; Ribeiro da Luz, B.; de Souza, Filho C.R.

    2009-01-01

    Recent Mars missions have stimulated considerable thinking about the surficial geochemical evolution of Mars. Among the major relevant findings are the presence in Meridiani Planum sediments of the mineral jarosite (a ferric sulfate salt) and related minerals that require formation from an acid-salt brine and oxidizing environment. Similar mineralogies have been observed in acidic saline lake sediments in Western Australia (WA), and these lakes have been proposed as analogues for acidic sedimentary environments on Mars. The prior version of the equilibrium chemical thermodynamic FREZCHEM model lacked Al and Si chemistries that are needed to appropriately model acidic aqueous geochemistries on Earth and Mars. The objectives of this work were to (1) add Al and Si chemistries to the FREZCHEM model, (2) extend these chemistries to low temperatures (<0 ??C), if possible, and (3) use the reformulated model to investigate parallels in the mineral precipitation behavior of acidic Australian lakes and hypothetical Martian brines. FREZCHEM is an equilibrium chemical thermodynamic model parameterized for concentrated electrolyte solutions using the Pitzer approach for the temperature range from <-70 to 25 ??C and the pressure range from 1 to 1000 bars. Aluminum chloride and sulfate mineral parameterizations were based on experimental data. Aluminum hydroxide and silicon mineral parameterizations were based on Gibbs free energy and enthalpy data. New aluminum and silicon parameterizations added 12 new aluminum/silicon minerals to this Na-K-Mg-Ca-Fe(II)-Fe(III)-Al-H-Cl-Br-SO4-NO3-OH-HCO3-CO3-CO2-O2-CH4-Si-H2O system that now contain 95 solid phases. There were similarities, differences, and uncertainties between Australian acidic, saline playa lakes and waters that likely led to the Burns formation salt accumulations on Mars. Both systems are similar in that they are dominated by (1) acidic, saline ground waters and sediments, (2) Ca and/or Mg sulfates, and (3) iron

  2. Modeling aluminum-silicon chemistries and application to Australian acidic playa lakes as analogues for Mars

    NASA Astrophysics Data System (ADS)

    Marion, G. M.; Crowley, J. K.; Thomson, B. J.; Kargel, J. S.; Bridges, N. T.; Hook, S. J.; Baldridge, A.; Brown, A. J.; Ribeiro da Luz, B.; de Souza Filho, C. R.

    2009-06-01

    Recent Mars missions have stimulated considerable thinking about the surficial geochemical evolution of Mars. Among the major relevant findings are the presence in Meridiani Planum sediments of the mineral jarosite (a ferric sulfate salt) and related minerals that require formation from an acid-salt brine and oxidizing environment. Similar mineralogies have been observed in acidic saline lake sediments in Western Australia (WA), and these lakes have been proposed as analogues for acidic sedimentary environments on Mars. The prior version of the equilibrium chemical thermodynamic FREZCHEM model lacked Al and Si chemistries that are needed to appropriately model acidic aqueous geochemistries on Earth and Mars. The objectives of this work were to (1) add Al and Si chemistries to the FREZCHEM model, (2) extend these chemistries to low temperatures (<0 °C), if possible, and (3) use the reformulated model to investigate parallels in the mineral precipitation behavior of acidic Australian lakes and hypothetical Martian brines. FREZCHEM is an equilibrium chemical thermodynamic model parameterized for concentrated electrolyte solutions using the Pitzer approach for the temperature range from <-70 to 25 °C and the pressure range from 1 to 1000 bars. Aluminum chloride and sulfate mineral parameterizations were based on experimental data. Aluminum hydroxide and silicon mineral parameterizations were based on Gibbs free energy and enthalpy data. New aluminum and silicon parameterizations added 12 new aluminum/silicon minerals to this Na-K-Mg-Ca-Fe(II)-Fe(III)-Al-H-Cl-Br-SO 4-NO 3-OH-HCO 3-CO 3-CO 2-O 2-CH 4-Si-H 2O system that now contain 95 solid phases. There were similarities, differences, and uncertainties between Australian acidic, saline playa lakes and waters that likely led to the Burns formation salt accumulations on Mars. Both systems are similar in that they are dominated by (1) acidic, saline ground waters and sediments, (2) Ca and/or Mg sulfates, and (3) iron

  3. N,N‧-Dimethylpiperazine mono-betaine complex with two molecules of 3-iodobenzoic acid and water studied by X-ray diffraction, DFT, FTIR and NMR methods

    NASA Astrophysics Data System (ADS)

    Dega-Szafran, Z.; Katrusiak, A.; Szafran, M.

    2008-03-01

    N, N'-Dimethylpiperazine mono-betaine ( N-carboxymethyl- N, N'-dimethylpiperazinium inner salt, MBPZ) forms a crystalline complex with two molecules of 3-iodobenzoic acid (3IBA). The complex crystallizes as a monohydrate, MBPZ(3IBA) 2H 2O. The complex has been characterized by X-ray diffraction and FTIR, Raman, 1H and 13C NMR spectroscopies. The crystals are monoclinic, space group P2 1/ c, with a = 6.7810(17), b = 38.391(4), c = 10.0542(16) Å, β = 90.024(18)°. The piperazinium ring has a chair conformation with the N +CH 2COO - substituent in the axial and both methyl groups in the equatorial positions. The 3IBA molecules interact with the carboxylate group of N +CH 2COO - and N' atom through the O-H···O and O-H···N hydrogen bonds of the lengths 2.550 and 2.695 Å. The water molecules link MBPZ(3IBA) 2 complexes by the O-H···OOCCH 2N + hydrogen bonds of 2.850 and 2.793 Å into infinite chains. The MBPZ(3XBA) 2H 2O (X = I, Br, Cl), MBPZ(3IBA) 2 complexes and MBPZ have been analyzed by the B3LYP/MidiX level of theory. The conformers with the axial CH 2COO - substituent have lower energies than these with the equatorial CH 2COO - one. The bands at 3433, 2790, 2450, 1915 cm -1 assigned to the ν(OH) vibration of the various hydrogen bonds, and two bands attributed to the ν(C dbnd O) (1680 cm -1) and ν as(COO) (1660 cm -1) vibrations in the FTIR spectrum confirm the structure of the title complex. The 1H- 13C HMBC spectrum has been analyzed in order to assign the carbon-13 chemical shifts.

  4. Cholesterol-deprivation increases mono-unsaturated very long-chain fatty acids in skin fibroblasts from patients with X-linked adrenoleukodystrophy.

    PubMed

    Engelen, M; Ofman, R; Mooijer, P A W; Poll-The, B T; Wanders, R J A; Kemp, S

    2008-03-01

    X-linked adrenoleukodystrophy (X-ALD) is the most common peroxisomal disorder and is characterized by a striking and unpredictable variation in phenotypic expression. It ranges from a rapidly progressive and fatal cerebral demyelinating disease in childhood (CCALD), to the milder slowly progressive form in adulthood (AMN). X-ALD is caused by mutations in the ABCD1 gene that encodes a peroxisomal membrane located ABC half-transporter named ALDP. Mutations in ALDP result in reduced beta-oxidation of very long-chain fatty acids (VLCFA, >22 carbon atoms) in peroxisomes and elevated levels of VLCFA in plasma and tissues. Previously, it has been shown that culturing skin fibroblasts from X-ALD patients in lipoprotein-deficient medium results in reduced VLCFA levels and increased expression of the functionally redundant ALD-related protein (ALDRP). The aim of this study was to further resolve the interaction between cholesterol and VLCFA metabolism in X-ALD. Our data show that the reduction in 26:0 in X-ALD fibroblasts grown in lipoprotein-deficient culture medium (free of cholesterol) is offset by a significant increase in both the level and synthesis of 26:1. We also demonstrate that cholesterol-deprivation results in increased expression of stearoyl-CoA-desaturase (SCD) and increased desaturation of 18:0 to 18:1. Finally, there was no increase in [1-(14)C]-26:0 beta-oxidation. Taken together, we conclude that cholesterol-deprivation reduces saturated VLCFA, but increases mono-unsaturated VLCFA. These data may have implications for treatment of X-ALD patients with lovastatin.

  5. 2005 Crater Lake Formation, Lahar, Acidic Flood, and Gas Emission From Chiginagak Volcano, Alaska

    NASA Astrophysics Data System (ADS)

    Schaefer, J. R.; Scott, W. E.; McGimsey, R. G.; Jorgenson, J.

    2005-12-01

    A 400-m-wide crater lake developed in the formerly snow-and-ice-filled crater of Mount Chiginagak volcano sometime between August 2004 and June 2005, presumably due to increased heat flux from the hydrothermal system. We are also evaluating the possible role of magma intrusion and degassing. In early summer 2005, clay-rich debris and an estimated 5.6 million cubic meters of acidic water from the crater exited through tunnels in the base of a glacier that breaches the south crater rim. Over 27 kilometers downstream, the acidic waters of the flood reached approximately 1.5 meters above current water levels and inundated an important salmon spawning drainage, acidifying at least the surface water of Mother Goose Lake (approximately 1 cubic kilometer in volume) and preventing the annual salmon run. No measurements of pH were taken until late August 2005. At that time the pH of water sampled from the Mother Goose Lake inlet, lake surface, and outlet stream (King Salmon River) was 3.2. Defoliation and leaf damage of vegetation along affected streams, in areas to heights of over 70 meters in elevation above flood level, indicates that a cloud of detrimental gas or aerosol accompanied the flood waters. Analysis of stream water, lake water, and vegetation samples is underway to better determine the agent responsible for the plant damage. This intriguing pattern of gas-damaged vegetation concentrated along and above the flood channels is cause for further investigation into potential hazards associated with Chiginagak's active crater lake. Anecdotal evidence from local lodge owners and aerial photographs from 1953 suggest that similar releases occurred in the mid-1970s and early 1950s.

  6. Algal and bacterial activities in acidic (pH 3) strip mine lakes

    SciTech Connect

    Gyure, R.A.; Konopka, A.; Brooks, A.; Doemel, W.

    1987-09-01

    Reservoir 29 and Lake B are extremely acid lakes (epilimnion pHs of 2.7 and 3.2, respectively), because they receive acidic discharges from coal refuse piles. They differ in that the pH of profundal sediments in Reservoir 29 increased from 2.7 to 3.8 during the period of thermal stratification, whereas permanently anoxic sediments in Lake B had a pH of 6.2. The pH rise in Reservoir 29 sediments was correlated with a temporal increase in H/sub 2/S concentration in the anaerobic hypolimnion from 0 to >1 mM. The chlorophyll a levels in the epilimnion of Reservoir 29 were low, and the rate of primary production was typical of an oligotrophic system. However, there was a dense 10-cm layer of algal biomass at the bottom of the metalimnion. Production by this layer was low owing to light limitation and possibly H/sub 2/S toxicity. The specific photosynthetic rates of epilimnetic algae were low, which suggests that nutrient availability is more important than pH in limiting production. The highest photosynthetic rates were obtained in water samples incubated at pH 2.7 to 4. Heterotrophic bacterial activity (measured by (/sup 14/C)glucose metabolism) was greatest at the sediment/water interface. Bacterial production (assayed by thymidine incorporation) was as high in Reservoir 29 as in a nonacid mesotrophic Indiana lake.

  7. Algal and Bacterial Activities in Acidic (pH 3) Strip Mine Lakes

    PubMed Central

    Gyure, Ruth A.; Konopka, Allan; Brooks, Austin; Doemel, William

    1987-01-01

    Reservoir 29 and Lake B are extremely acid lakes (epilimnion pHs of 2.7 and 3.2, respectively), because they receive acidic discharges from coal refuse piles. They differ in that the pH of profundal sediments in Reservoir 29 increased from 2.7 to 3.8 during the period of thermal stratification, whereas permanently anoxic sediments in Lake B had a pH of 6.2. The pH rise in Reservoir 29 sediments was correlated with a temporal increase in H2S concentration in the anaerobic hypolimnion from 0 to >1 mM. The chlorophyll a levels in the epilimnion of Reservoir 29 were low, and the rate of primary production was typical of an oligotrophic system. However, there was a dense 10-cm layer of algal biomass at the bottom of the metalimnion. Production by this layer was low owing to light limitation and possibly H2S toxicity. The specific photosynthetic rates of epilimnetic algae were low, which suggests that nutrient availability is more important than pH in limiting production. The highest photosynthetic rates were obtained in water samples incubated at pH 2.7 to 4. Heterotrophic bacterial activity (measured by [14C]glucose metabolism) was greatest at the sediment/water interface. Bacterial production (assayed by thymidine incorporation) was as high in Reservoir 29 as in a nonacid mesotrophic Indiana lake. PMID:16347430

  8. Australian Acid Playa Lake as a Mars Analog: Results from Sediment Lipid Analysis

    NASA Astrophysics Data System (ADS)

    Graham, H.; Baldridge, A. M.; Stern, J. C.

    2015-12-01

    The ephemeral saline acidic lakes on the Yilgarn Craton of Western Australia have been suggested as geochemical analogues to martian terrains. Both are characterized by interbedded phyllosilicates and hydrated sulfates. On Mars, these areas indicate shifting environmental conditions, from the neutral/alkaline and wet conditions that dominated during the Noachian era to the more familiar dry, acidic conditions that began in the Hesperian. The habitability of such a dynamic environment can be informed by investigation of the Yilgarn Lake system. Previous work has found phospholipid fatty acids (PLFA) evidence of microbial communities in sections of sediment cores taken from Lake Gilmore. These communities include both Gram-positive and -negative bacteria, Actinomycetes, and even methanotrophs. Given recurring detection of methane on the martian surface, evidence of a methane cycling community in an analogous environment is of particular interest. In this study we analyze the carbon isotope composition of bulk organic material as well as extracted lipids from the Lake Gilmore sediment cores at both a near-shore and mid-lake location. These analyses reveal very low accumulations of organic carbon, concentrated primarily in the gypsum-rich near-shore core. The near-shore sediments show a down-core decrease in abundance of organic carbon as well as depletion in the carbon isotope composition (δ13C) with depth. Bulk carbon did not exhibit the unique, highly depleted, diagnostic signature associated with methanotrophic biomass. Compound-specific isotope analysis (CSIA) of carbon in extracted methanotroph PFLAs can confirm the presence of a methane cycling metabolism at depth. Also, additional extractions have isolated lipids associated with lake-edge grasses. These analyses consider both the chain-length distribution and carbon CSIA of these lipids in order to understand the effect of terrestrial detritus on any preserved methanotroph carbon signal, given the very low

  9. Trends in summer chemistry linked to productivity in lakes recovering from acid deposition in the Adirondack region of New York

    USGS Publications Warehouse

    Momen, B.; Lawrence, G.B.; Nierzwicki-Bauer, S. A.; Sutherland, J.W.; Eichler, L.W.; Harrison, J.P.; Boylen, C.W.

    2006-01-01

    The US Environmental Protection Agency established the Adirondack Effects Assessment Program (AEAP) to evaluate and monitor the status of biological communities in lakes in the Adirondack region of New York that have been adversely affected by acid deposition. This program includes chemical analysis of 30 lakes, sampled two to three times each summer. Results of trends analysis for lake chemistry and chlorophyll a (chlor a) are presented for 1994 to 2003, and a general comparison is made with recent results of the Adirondack Long-Term Monitoring (ALTM) Program, which included chemical analysis of all but two of these lakes (plus an additional 24 lakes) monthly, year-round for 1992-2004. Increases in pH were found in 25 of the 30 AEAP lakes (P < 0.05) and increases in acid-neutralizing capacity (ANC) were found in 12 of the 30 lakes (P < 0.05). Concentrations of both SO 42- and Mg 2+ decreased in 11 lakes (P < 0.05), whereas concentrations of NO 3- decreased in 20 lakes (P < 0.05). Concentrations of NH 4+ decreased in 10 lakes at a significance level of P < 0.05 and in three other lakes based on P < 0.1. Concentrations of inorganic and organic monomeric aluminum generally were below the reporting limit of 1.5 ??mol L-1, but decreases were detected in four and five lakes, respectively (P < 0.1). Concentrations of chlor a increased in seven lakes at a significance level of P < 0.05 and two lakes at a significance level of P < 0.1. A significant inverse correlation was also found between chlor a and NO 3- concentrations in nine lakes at a significance level of P < 0.05 and two lakes at a significance level of P < 0.1. Results of AEAP analysis of lake chemistry were similar to those of the ALTM Program, although decreases in SO 42- concentrations were more evident in the year-round ALTM record. Overall, the results suggest (a) a degree of chemical recovery from acidification during the summer, (b) an increase in phytoplankton productivity, and (c) a decreasing trend in

  10. Long-term recovery of lakes in the Adirondack region of New York to decreases in acidic deposition

    NASA Astrophysics Data System (ADS)

    Waller, Kristin; Driscoll, Charles; Lynch, Jason; Newcomb, Dani; Roy, Karen

    2012-01-01

    After years of adverse impacts to the acid-sensitive ecosystems of the eastern United States, the Acid Rain Program and Nitrogen Budget Program were developed to control sulfur dioxide (SO 2) and nitrogen oxide (NO x) emissions through market-based cap and trade systems. We used data from the National Atmospheric Deposition Program's National Trends Network (NTN) and the U.S. EPA Temporally Integrated Monitoring of Ecosystems (TIME) program to evaluate the response of lake-watersheds in the Adirondack region of New York to changes in emissions of sulfur dioxide and nitrogen oxides resulting from the Acid Rain Program and the Nitrogen Budget Program. TIME is a long-term monitoring program designed to sample statistically selected subpopulations of lakes and streams across the eastern U.S. to quantify regional trends in surface water chemistry due to changes in atmospheric deposition. Decreases in wet sulfate deposition for the TIME lake-watersheds from 1991 to 2007 (-1.04 meq m -2-yr) generally corresponded with decreases in estimated lake sulfate flux (-1.46 ± 0.72 meq m -2-yr), suggesting declines in lake sulfate were largely driven by decreases in atmospheric deposition. Decreases in lake sulfate and to a lesser extent nitrate have generally coincided with increases in acid neutralizing capacity (ANC) resulting in shifts in lakes among ANC sensitivity classes. The percentage of acidic Adirondack lakes (ANC <0 μeq L -1) decreased from 15.5% (284 lakes) to 8.3% (152 lakes) since the implementation of the Acid Rain Program and the Nitrogen Budget Program. Two measures of ANC were considered in our analysis: ANC determined directly by Gran plot analysis (ANC G) and ANC calculated by major ion chemistry (ANC calc = CB - CA). While these two metrics should theoretically show similar responses, ANC calc (+2.03 μeq L -1-yr) increased at more than twice the rate as ANC G (+0.76 μeq L -1-yr). This discrepancy has important implications for assessments of lake recovery

  11. Effect of diacylglycerol acyltransferase 2 overexpression in 3T3-L1 is associated to an increase in mono-unsaturated fatty acid accumulation

    PubMed Central

    2014-01-01

    Background Fatty acid (FA) composition is the most important parameter affecting the flavor and nutritional value of the meat. The final and the only committed step in the biosynthesis of triglycerides is catalyzed by diacylglycerol acyltransferase 2 (DGAT2). The role of DGAT2 in lipid accumulation has been demonstrated in adipocytes, However, little is known about the effect of DGAT2 on the FA composition of these cells. Methods To investigate the role of DGAT2 in regulating lipid accumulation, FA composition and the expression of adipogenic genes, we cloned the open reading frame of the porcine DGAT2 gene and established 3T3-L1 cells that overexpressed DGAT2. Cells were then cultured in differentiation medium (DM) without FA, with a mixture of FAs (FA-DM), or containing a 13C stable isotope-labeled FA mixture (IFA-DM). The FA composition of adipocytes was analyzed by gas chromatography–mass spectrometry and gas chromatography-isotope ratio mass spectrometry. Quantitative PCR and western blotting were employed to detect expression of adipogenic genes in 3T3-L1 adipocytes cultured with FA-DM for 12 d. Results The triacylglyceride (TAG) content was significantly higher in 3T3-L1 adipocytes overexpressing DGAT2 than in control cells. When cultured in DM or FA-DM for 12 d, cells overexpressing DGAT2 showed a higher proportion of unsaturated FAs (C16:1 and C18:1). However, when cells overexpressing DGAT2 were cultured with FA-DM for 30 min, the FA composition was almost identical to that of controls. Further, the proportion of stable isotope-labeled FAs were similar in 3T3-L1 adipocytes overexpressing DGAT2 and control cells cultured in IFA-DM for 12 d. These results collectively indicate that the higher proportion of mono-unsaturated FAs, C16:1 and C18:1, may originate from de novo FA synthesis but not from the uptake of specific FAs from the medium. This hypothesis is further supported by evidence that both mRNA and protein expression of genes involved in FA

  12. Detection of a cyclic perfluorinated acid, perfluoroethylcyclohexane sulfonate, in the Great Lakes of North America.

    PubMed

    De Silva, Amila O; Spencer, Christine; Scott, Brian F; Backus, Sean; Muir, Derek C G

    2011-10-01

    Perfluoroethylcyclohexanesulfonate (PFECHS) is a cyclic perfluorinated acid (PFA) mainly used as an erosion inhibitor in aircraft hydraulic fluids. It is expected to be as recalcitrant to environmental degradation as aliphatic PFAs including perfluorooctanoate (PFOA) and perfluorooctane sulfonate (PFOS). For the first time, PFECHS is reported in top predator fish (Lakes and in surface waters (0.16-5.7 ng L(-1)). PFOS was the major aliphatic PFA in fish from the Great Lakes. Concentrations of most of the PFAs were not statistically different from previously reported 2004 trout data in Lake Ontario. Shorter chain perfluorocarboxylates were prevalent in surface waters of the Great Lakes, dominated by PFOA (0.65-5.5 ng/L). An impurity in the commercial PFECHS formulation, perfluoromethylcyclohexane sulfonate (PFMeCHS), was also detected in the dissolved phase but not above detection limits in fish tissue. Bioaccumulation factors (BAFs) were estimated by taking the ratio of fish to water concentrations. The mean log BAF values corresponded to 2.8 for PFECHS, 2.1 for PFOA, and 4.5 for PFOS. It is not certain whether the fish-water BAF for PFECHS is an overestimate due to the influence of precursor biotransformation. Further studies are recommended to understand the extent of PFECHS contamination.

  13. O sbnd H⋯O and O sbnd H⋯N hydrogen bonds in the complex of DABCO mono-betaine with p-hydroxybenzoic acid studied by X-ray diffraction, DFT calculations and spectroscopic methods

    NASA Astrophysics Data System (ADS)

    Barczyński, P.; Dega-Szafran, Z.; Katrusiak, A.; Szafran, M.

    2011-08-01

    DABCO mono-betaine (1,4-diazabicyclo[2.2.2]octane-1-acetate) forms a complex with p-hydroxybenzoic acid (HBA) at the 1:1 ratio. The crystals are monoclinic, space group P2 1/ m. The HBA and DABCO mono-betaine molecules are linked into infinite chains through the COOH⋯OOC and O sbnd H⋯N hydrogen bonds of 2.604(1) and 2.771(2) Å, respectively. The DABCO mono-betaine is located on a mirror plane and the HBA molecule lies on this plane. In the structure of the 1:1 complex optimized by the B3LYP/6-31G(d,p) approach, the DABCO ring has a planar conformation, while in the chains formed by two complexes, the DABCO moieties assume the propeller conformations. The FTIR spectrum shows several bands attributed to the O sbnd H, O sbnd H⋯O, O sbnd H⋯N, C dbnd O and COO stretching vibrations. 1H and 13C chemical shifts assignments were confirmed by the magnetic isotropic shielding constants, calculated by the GIAO/B3LYP/6-31G(d,p) approach.

  14. Perfluoroalkyl acids in the egg yolk of birds from Lake Shihwa, Korea.

    PubMed

    Yoo, Hoon; Kannan, Kurunthachalam; Kim, Seong Kyu; Lee, Kyu Tae; Newsted, John L; Giesy, John P

    2008-08-01

    Concentrations of perfluoroalkyl acids (PFAs) were measured in egg yolks of three species of birds, the little egret (Egretta garzetta), little ringed plover (Charadrius dubius), and parrot bill (Paradoxornis webbiana), collected in and around Lake Shihwa, Korea, which receives wastewaters from an adjacent industrial complex. Mean concentrations of perfluorooctanesulfonate (PFOS) ranged from 185 to 314 ng/g ww and were similar to those reported for bird eggs from other urban areas. Long-chain perfluorocarboxylic acids (PFCAs) were also found in egg yolks often at great concentrations. Mean concentrations of perfluoroundecanoic acid (PFUnA) ranged from 95 to 201 ng/g ww. Perfluorooctanoic acid was detected in 32 of 44 egg samples, but concentrations were 100-fold less than those of PFOS. Relative concentrations of PFAs in all three species were similar with the predominance of PFOS (45-50%). There was a statistically significant correlation between PFUnA and perfluorodecanoic acid in egg yolks (p < 0.05), suggesting a common source of PFCAs. Using measured egg concentrations and diet concentrations, the ecological risk of the PFOS and PFA mixture to birds in Lake Shihwa was evaluated using two different approaches. Estimated hazard quotients were similar between the two approaches. The concentration of PFOS associated with 90th centile in bird eggs was 100-fold less than the lowest observable adverse effect level determined for birds, and those concentrations were 4-fold less than the suggested toxicity reference values. On the basis of limited toxicological data, current concentrations of PFOS are less than what would be expected to have an adverse effect on birds in the Lake Shihwa region.

  15. Using Fiber Optic Distributed Temperature Sensing (DTS) to Assess Groundwater-Lake Exchange in an Acid Mine Lake in Eastern Germany

    NASA Astrophysics Data System (ADS)

    Hausner, M. B.; Fleckenstein, J.; Neumann, C.; Tyler, S. W.

    2008-12-01

    Groundwater flows through contaminated mine sites are a major concern in many parts of the world. In this study, a variety of instrumentation was used to locate and quantify groundwater inflows into an acid lake on an abandoned mine site in Brandenburg, Germany. While previously-installed piezometers and seepage meters had identified several points of groundwater influx into the lake, such techniques are spatially limited to the point of installation. To address this limitation, a fiber-optic distributed temperature sensor (DTS) was deployed across the lake bottom and in vertical profilers to confirm and expand the previously generated data sets. Fiber-optic DTS, a relatively new technology, provides the opportunity to measure temperature on very high spatial and temporal scales using Raman spectra scattering of pulsed light within a glass fiber. A 1000 meter cable was deployed spatially along the sediment-water interface to identify spatially scattered areas of groundwater inflow, while two high-resolution probes (which return temperature readings every 2.4 vertical cm) were installed vertically near existing seepage meters. Preliminary analysis of the vertical deployments showed substantial groundwater upwelling, confirming the results of previous seepage meter measurements which showed significant vertical flux into the lake. Ongoing analysis of the lateral deployment is expected to identify areas in which there are anomalies in the diurnal temperature cycle at the lake bottom; such anomalies may indicate groundwater influx into the lake. These areas will be used to locate future seepage meter and piezometer installations.

  16. Common Loon (Gavia immer) eggshell thickness and egg volume vary with acidity of nest lake in northern Wisconsin

    USGS Publications Warehouse

    Pollentier, C.D.; Kenow, K.P.; Meyer, M.W.

    2007-01-01

    Environmental acidification has been associated with factors that may negatively affect reproduction in many waterbirds. Declines in lake pH can lead to reductions in food availability and quality, or result in the altered availability of toxic metals, such as mercury. A recent laboratory study conducted by the U.S. Geological Survey and the Wisconsin Department of Natural Resources indicated that Common Loon (Gavia immer) chicks hatched from eggs collected on acidic lakes in northern Wisconsin may be less responsive to stimuli and exhibit reduced growth compared to chicks from neutral-pH lakes. Here we report on the relation between Common Loon egg characteristics (eggshell thickness and egg volume) and lake pH, as well as eggshell methylmercury content. Eggs (N = 84) and lake pH measurements were obtained from a four county region of northern Wisconsin. Egg-shells were 3-4% thinner on lakes with pH ??? 6.3 than on neutral-pH lakes and this relation was linear across the pH range investigated (P 0.05, n.s.) or lake pH. Results suggest that low lake pH may be associated with thinner eggshells and reduced egg volume in Common Loons. We speculate on the mechanisms that may lead to this phenomeno.

  17. Exploring Variability in Acidic Saline Playa Lakes in WA with HyMAP Hyperspectral Data

    NASA Astrophysics Data System (ADS)

    Baldridge, A. M.; Hook, S. J.; Souza Filho, C. R.; Thomson, B. J.; Bridges, N. T.; Crowley, J. K.

    2009-12-01

    Acid saline lakes in Western Australia have been recognized as useful chemical terrestrial analogs for aqueous mineral formation on Mars [e.g., 1]. In these lake systems, large pH and salinity differences are observed both laterally and vertically over scales of a few tens of meters[2, 3]. The variability in these lakes have been offered as an alternate formation mechanism for some of the phyllosilicates and sulfates on Mars, suggesting that these different mineral types may be separated by chemical gradients rather than by temporal boundaries[4]. To assess the ability to detect this variability remotely and to determine the extent of the surface variability, which may not be easily accessible in the field, spectral mapping for two of the acidic saline playa lakes was performed. HyMAP airborne data were acquired in December, 2008, of Lake Gilmore and Lake Chandler in WA. The HyMAP sensors have 126 bands that cover the wavelength range between 0.45 and 2.5 µm. Hyvista Corporation provided atmospherically corrected surface reflectance data at approximately 3m spatial resolution. Using the methodology described by [5] the HyMAP data were analyzed using ENVI to identify spectrally pure endmembers that can be used to distinguish mineralogy in the scene. Relevant (e.g. not roads, water or vegetation) spectral endmembers derived for each scene were identified visually using spectra from the ASTER spectral library[6]. The processing techniques were applied to all flight lines and ultimately a classification map mosaic was produced for selection of relevant and intriguing field sampling sites. The classification maps will be validated using field spectroscopy and visual inspection of representative samples collected from the field sites in October 2009, and laboratory spectroscopy and X-ray diffraction will be performed for further validation. The classification maps confirm variability in mineralogy across the lakes, validating geochemical modeling. There are also some

  18. Fatty Acid composition of the muscle lipids of five fish species in işıklı and karacaören dam lake, Turkey.

    PubMed

    Citil, Ozcan Baris; Kalyoncu, Leyla; Kahraman, Oguzhan

    2014-01-01

    Total fatty acid composition of muscle lipids in some fish species (Cyprinus carpio (Işıklı Dam Lake), Tinca tinca (Işıklı Dam Lake), Scardinius erythrophthalmus (Işıklı Dam Lake), Cyprinus carpio (Karacaören Dam Lake), and Carassius carassius (Karacaören Dam Lake)) was determined by gas chromatography. Polyunsaturated fatty acids (PUFAs) of Cyprinus carpio (Işıklı Dam Lake) were found higher than PUFA of other species. Palmitic acid was the highest saturated fatty acid (SFA) in Tinca tinca (24.64%). Oleic acid was the highest monounsaturated fatty acid (MUFAs) in Cyprinus carpio (Işıklı Dam Lake) (19.25%). The most abundant polyunsaturated fatty acid in Scardinius erythrophthalmus was docosahexaenoic acid (DHA) (17.94%). Total ω3 fatty acid composition was higher than the total ω6 fatty acids of Cyprinus carpio in both dam lakes. ω3/ω6 rates in Cyprinus carpio (Işıklı Dam Lake), Tinca tinca, Scardinius erythrophthalmus, Cyprinus carpio (Karacaören), and Carassius carassius were 2.12, 1.19, 2.15, 2.87, and 2.82, respectively.

  19. Using Australian Acidic Playa Lakes as Analogs for Phyllosilicate and Sulfate Depositional Environments on Mars

    NASA Astrophysics Data System (ADS)

    Baldridge, A. M.; Michalski, J.; Kargel, J.; Hook, S.; Marion, G.; Crowley, J.; Bridges, N.; Brown, A.; Ribeiro da Luz, B.; de Souza Filho, C. R.; Thomson, B.

    2008-12-01

    Recent work on the origin of martian sulfates and their relationship to phyllosilicate deposits suggest that these deposits formed in different eras of Mars' history, under distinct environmental conditions. In southwestern Meridiani Planum phyllosilicates exist in close proximity to sulfate deposits. One possible explanation for this relationship is that it is an unconformable stratigraphic sequence, representing a significant change in aqueous geochemical conditions over time. Specifically, it may be interpreted to record a change in environment from neutral pH aqueous alteration in the Noachian to an acidic evaporitic system in the late Noachian to the Hesperian. On Earth, two different geochemical systems need not be evoked to explain such chemical variation. Acidic playa lakes in Western Australia have large pH differences separated by only a few tens of meters and demonstrate how highly variable chemistries can coexist over short distances in natural environments. Playa lakes on Earth tend to be dominated by lateral flow of water and salts leading to lateral chemical variation. Heterogeneity of playa mineralogy in Australia is due to the varied source rocks of brines and the mixing of dilute oxidizing brines and freshwater with the saturated evaporitic brines. This is evidenced by the ferricretes in the near-shore environment and more soluble phases in basin interiors. Playa lakes on Mars would be much larger than their terrestrial counterparts, leading to the prevalence of large-scale surface and crustal advection of water and salt rather than short-distance lateral flow, except at lake boundaries. Little or no influx of freshwater would preclude the formation of playa rim (e.g., crater rim) ferricretes and silcretes. Instead, we expect to see mainly vertical facies changes, and any diachronous lateral facies changes are expected to occur on very large spatial scales. Comparison of high spatial resolution, hyperspectral airborne data for Australian playa

  20. Spatial characterization of acid rain stress in Canadian Shield Lakes. Progress report, 1 August 1986-1 February 1987

    SciTech Connect

    Tanis, F.J.

    1987-01-01

    The acidification of lake waters from airborne pollution is of continental proportions both in North America and Europe. A major concern of the acid rain problem is the cumulative ecosystem damage to lakes and forest. The number of lakes affected in northeastern U.S. and on the Canadian Shield is though to be enormous. How seasonal changes in lake transparency are related to annual acidic load was examined. The relationship between variations in lake acidification and ecophysical units was also examined. The utility of Thematic Mapper based observations to measure seasonal changes in the optical transparency in acid lakes was investigated. The potential for this optical response is related to a number of local ecophysical factors with bedrock geology being, perhaps, the most important. Other factors include sulfate deposition, vegetative cover, and terrain drainage/relief. The area of southern Ontario contains a wide variety of geologies from the most acid rain sensitive granite quartzite types to the least sensitive limestone dolomite sediments. Annual sulfate deposition ranges from 1.0 to 4.0 grams/sq m.

  1. Chemical, crystallographic and stable isotopic properties of alunite and jarosite from acid-Hypersaline Australian lakes

    USGS Publications Warehouse

    Alpers, C.N.; Rye, R.O.; Nordstrom, D.K.; White, L.D.; King, B.-S.

    1992-01-01

    Chemical, crystallographic and isotopic analyses were made on samples containing alunite and jarosite from the sediments of four acid, hypersaline lakes in southeastern and southwestern Australia. The alunite and jarosite are K-rich with relatively low Na contents based on chemical analysis and determination of unit cell dimensions by powder X-ray diffraction. Correcting the chemical analyses of fine-grained mineral concentrates from Lake Tyrrell, Victoria, for the presence of halite, silica and poorly crystalline aluminosilicates, the following formulas indicate best estimates for solid-solution compositions: for alunite, K0.87Na0.04(H3O)0.09(Al 0.92Fe0.08)3(SO4)2(OH) 6 and for jarosite, K0.89Na0.07(H3O)0.04(Fe 0.80Al0.20)3(SO4)2(OH) 6. The ??D-values of alunite are notably larger than those for jarosite from Lake Tyrrell and it appears that the minerals have closely approached hydrogen isotope equilibrium with the acidic regional groundwaters. The ??D results are consistent with a fractionation ???60-70??? between alunite and jarosite observed in other areas. However, interpretation of ??D results is complicated by large variability in fluid ??DH2O from evaporation, mixing and possible ion hydration effects in the brine. ??D-values of water derived from jarosite by step-wise heating tend to be smaller at 250??C, at which temperature hydronium and other non-hydroxyl water is liberated, than at 550??C, where water is derived from the hydroxyl site, but the differences are not sufficiently different to invalidate measurements of total ??D obtained by conventional, single-step heating methods. ??34S-values for alunite and jarosite from the four lakes (+19.7 to +21.2??? CDT) and for aqueous sulfate from Lake Tyrrell (+18.3 to +19.8???) are close to the values for modern evaporites (+21.5 ??0.3???) and seawater (+20??0.5???) and are probably typical of seawater-derived aerosols in arid coastal environments. ??34-S-values slightly smaller than that for seawater may

  2. Inorganic carbon limitation and mixotrophic growth in Chlamydomonas from an acidic mining lake.

    PubMed

    Tittel, Jörg; Bissinger, Vera; Gaedke, Ursula; Kamjunke, Norbert

    2005-06-01

    Plankton communities in acidic mining lakes (pH 2.5-3.3) are species-poor because they face extreme environmental conditions, e.g. 150mg l(-1) Fe2+ +Fe3+. We investigated the growth characteristics of the dominant pigmented species, the flagellate Chlamydomonas acidophila, in semi-continuous culture experiments under in situ conditions. The following hypotheses were tested: (1) Low inorganic carbon (IC) concentrations in the epilimnion (e.g. 0.3 mg l(-1)) arising from the low pH limit phototrophic growth (H-1); (2) the additional use of dissolved organic carbon (mixotrophy) leads to higher growth rates under IC-limitation (H-2), and (3) phagotrophy is not relevant (H-3). H-1 was supported as the culture experiments, in situ PAR and IC concentrations indicated that IC potentially limited phototrophic growth in the mixed surface layers. H-2 was also supported: mixotrophic growth always exceeded pure phototrophic growth even when photosynthesis was saturated. Dark growth in filtered lake water illuminated prior to inoculation provided evidence that Chlamydomonas was able to use the natural DOC. The alga did not grow on bacteria, thus confirming H-3. Chlamydomonas exhibited a remarkable resistance to starvation in the dark. The compensation light intensity (ca. 20 micromol photons m(-2) s(-1)) and the maximum phototrophic growth (1.50 d(-1)) fell within the range of algae from non-acidic waters. Overall, Chlamydomonas, a typical r-strategist in circum-neutral systems, showed characteristics of a K-strategist in the stable, acidic lake environment in achieving moderate growth rates and minimizing metabolic losses.

  3. Mono County update

    SciTech Connect

    Lyster, D. )

    1988-12-01

    The Mono County Board of Supervisors approved the issuance of a use-permit for the Mammoth-Pacific II geothermal power plant. The power plant will be a binary, air-cooled, 10-megawatt, net, project. An appeal was filed by the California Department of Fish and Game, and the permit will not take effect until this appeal is resolved. Mono County also issued a project use-permit to proposers of Bonneville Pacific Corporations Mammoth Chance Geothermal Project, also a 10-megawatt, net, binary and air-cooled project. The permit was appealed by the Sierra Club, Cal-Trout, and the California Department of Fish and Game. Now, a subsequent EIR must be prepared for public review and comment. The subsequent EIR will address the issue of cumulative impacts and will include a discussion of new information.

  4. Dust Storms From Owens and Mono Valleys, California

    DTIC Science & Technology

    1986-09-01

    developed a model that predicts that the level of Mono Lake will stabilize at 6.223 feet just after the year 2050, if the present water export and...done on the behavior of the saline components. and models were c’nstructed usint! lake-bed clays and brines. We visited the plava monthly in 1985. 21...lake bed. Spiralling streamers of dust arose from south of the water body to the region of the sand dunes, where an opaque cloud rose to 8,500 feet

  5. Composition and copper binding properties of aquatic fulvic acids in eutrophic Taihu Lake, China.

    PubMed

    Li, Weiwei; Zhang, Fenfen; Ye, Qi; Wu, Dan; Wang, Liying; Yu, Yihua; Deng, Bing; Du, Jinzhou

    2017-04-01

    Fulvic acid (FA) plays a significant role in biogenic-elemental cycling in aquatic ecosystems which is highly dependent on their organic composition. In this study, the aquatic FA contents and binding properties during bloom and non-bloom periods in Taihu Lake were investigated by two-dimensional correlation spectroscopy Fourier transform infrared spectroscopy (2D-COS-FTIR), nuclear magnetic resonance (NMR) and elemental analysis. Compared with non-bloom FA, bloom FA was of lower nitrogen content and higher C/N ratio. It contained more carboxylic and aliphatic groups while less amide groups. 2D-COS-FTIR spectra evidenced the carboxyl groups in bloom FA had the fastest response to Cu(II) binding. Also, polysaccharide in bloom FA was more susceptive to Cu(II) concentrations than that in non-bloom FA. While comparing with bloom FA, the N-rich organic compounds in non-bloom FA exhibited faster binding sequence with Cu(II). A comprehensive scheme about the interaction process of FA-Cu(II) showed that both nitrogenous and oxygenic groups in FAs were active in binding to Cu(II). The alteration in binding behaviors of organic groups in FAs to Cu(II) may have been driven by algal products and microbial community variety in Taihu Lake. Our results here have the potential to contribute significantly to future studies of dissolved organic matter dynamic biogeochemistry processes and trace metal cycling processes in eutrophic lakes.

  6. Dissolution of resin acids, retene and wood sterols from contaminated lake sediments.

    PubMed

    Meriläinen, Päivi; Lahdelma, Ilpo; Oikari, Laura; Hyötyläinen, Tarja; Oikari, Aimo

    2006-10-01

    The dissolution potency of hydrophobic resin acids (RAs), retene and wood sterols from sediments was studied. These wood extractives and their metabolites are sorbed from pulp and paper mill effluents to downstream sediments. With harmful components like these, sediments can pose a hazard to the aquatic environment. Therefore, sediment elutriates with water were produced under variable conditions (agitation rate and efficiency, time), and concentrations of the dissoluted compounds were analyzed. Both naturally contaminated field sediments and artificially spiked sediments were studied. By vigorous agitation RAs can be released fast from the sediment matrix and equilibrium reached within 3 days. Compared to RAs, desorption of retene from lake sediment was slower and did not completely reach equilibrium in 23 days. Sterols spiked to pristine sediment with a 33-day contact time desorbed faster than those associated authentically with industrial sediment of from a contaminated lake. Simulating the water turbulence adjacent to a sediment surface by low and high rate of agitation in the laboratory, an increase in the mixing rate after 43-day elutriation suddenly released a high amount of wood sterols. The results indicate wide variation between hazardous chemicals in their tendency to dissolution from sediment solids. Erosion and hydrology adjacent to the sediment surface, as well as risks from dredging activities of sediments, may expose lake biota to bioactive chemicals.

  7. Influence of copper recovery on the water quality of the acidic Berkeley Pit lake, Montana, U.S.A.

    PubMed

    Tucci, Nicholas J; Gammons, Christopher H

    2015-04-07

    The Berkeley Pit lake in Butte, Montana, formed by flooding of an open-pit copper mine, is one of the world's largest accumulations of acidic, metal-rich water. Between 2003 and 2012, approximately 2 × 10(11) L of pit water, representing 1.3 lake volumes, were pumped from the bottom of the lake to a copper recovery plant, where dissolved Cu(2+) was precipitated on scrap iron, releasing Fe(2+) back to solution and thence back to the pit. Artificial mixing caused by this continuous pumping changed the lake from a meromictic to holomictic state, induced oxidation of dissolved Fe(2+), and caused subsequent precipitation of more than 2 × 10(8) kg of secondary ferric compounds, mainly schwertmannite and jarosite, which settled to the bottom of the lake. A large mass of As, P, and sulfate was also lost from solution. These unforeseen changes in chemistry resulted in a roughly 25-30% reduction in the lake's calculated and measured total acidity, which represents a significant potential savings in the cost of lime treatment, which is not expected to commence until 2023. Future monitoring is needed to verify that schwertmannite and jarosite in the pit sediment do not convert to goethite, a process which would release stored acidity back to the water column.

  8. Mono County update

    SciTech Connect

    Lyster, D.L.

    1987-06-01

    On February 9, 1988, the Mono County Board of Supervisors voted to approve Bonneville Pacific Corporation's Mammoth Chance Geothermal Project. The project is an air-cooled, binary, geothermal power plant, 10 megawatts, net. The Mono County Board of Supervisors issued a project use-permit with vigorous and stringent conditions. Specific emphasis was placed on the establishment of a monitoring program designed to detect the effects of geothermal development on the springs at the Hot Creek Fish Hatchery and Hot Creek Gorge. On October 5, 1987, the Mono County Planning Commission granted a use-permit to Mammoth Pacific for its Mammoth Pacific II Project, a binary, air-cooled, geothermal power plant, 10 megawatts, net. The issuance of the use-permit instigated an appeal by the Sierra Club. That appeal was heard on February 22, 1988, At the end of the testimony, the Board of Supervisors voted to uphold the appeal of the Sierra Club, thereby denying the project by a vote of 3 to 2. The main areas of concern voiced by the majority of the Board included potential hydrologic impacts to Hot Creek Gorge and Hot Creek Fish Hatchery, visual impacts, and impacts to mule deer migration and survival. One of the options now available to Mammoth Pacific is to request that the project be denied without prejudice. This would allow Mammoth Pacific to return to the Board immediately with additional material regarding its concerns.

  9. Fatty acid composition of freshwater wild fish in subalpine lakes: a comparative study.

    PubMed

    Vasconi, Mauro; Caprino, Fabio; Bellagamba, Federica; Busetto, Maria Letizia; Bernardi, Cristian; Puzzi, Cesare; Moretti, Vittorio Maria

    2015-03-01

    In this study, the proximate and fatty acid compositions of the muscle tissue of 186 samples of fish belonging to fifteen species of freshwater fish harvested in subalpine lakes (bleak, shad, crucian carp, whitefish, common carp, pike, black bullhead, burbot, perch, Italian roach, roach, rudd, wels catfish, chub and tench) were investigated. Most of the fish demonstrated a lipid content in the fillet lower than 2.0 g 100 g(-1) wet weight (range 0.6-9.7). A strong relationship between feeding behavior and fatty acid composition of the muscle lipids was observed. Planktivorous fish showed the lowest amounts of n-3 fatty acids (p < 0.05), but the highest monounsaturated fatty acid (MUFA) contents, in particular 18:1n-9. Conversely, carnivorous fish showed the highest amounts of saturated fatty acids and n-3 fatty acids (p < 0.05), but the lowest MUFA contents. Omnivorous fish showed substantial proportions of n-3 fatty acids and the highest contents of n-6 fatty acids. Principal component analysis showed a distinct separation between fish species according to their feeding habits and demonstrated that the most contributing trophic markers were 18:1n-9, 18:3n-3, 22:6n-3 and 20:4n-6. The quantitative amounts n-3 polyunsaturated fatty acid in muscle tissues varied depending on the fish species, the lipid content and the feeding habits. Some species were very lean, and therefore would be poor choices for human consumption to meet dietary n-3 fatty acid requirements. Nevertheless, the more frequently consumed and appreciated fish, shad and whitefish, had EPA and DHA contents in the range 900-1,000 mg 100 g(-1) fresh fillet.

  10. The Organic Content of the Tagish Lake Meteorite

    NASA Technical Reports Server (NTRS)

    Pizzarello, Sandra; Huang, Yongsong; Becker, Luann; Poreda, Robert J.; Nieman, Ronald A.; Cooper, George; Williams, Michael

    2001-01-01

    The Tagish Lake meteorite felt last year on a frozen take in Canada and may provide the most pristine material of its kind. Analyses have now shown this carbonaceous chondrite to contain a suite of soluble organic compounds (approximately 100 parts per million) that includes mono- and dicarboxylic acids, dicarboximides, pyridine carboxylic acids, a sulfonic acid, and both aliphatic and aromatic hydrocarbons. The insoluble carbon exhibits exclusive aromatic character, deuterium enrichment, and fullerenes containing 'planetary' helium and argon. The findings provide insight into an outcome of early solar chemical evolution that differs from any seen so far in meteorites.

  11. Use of sequential sampling of amphipod abundance to classify the biotic integrity of acid-sensitive lakes

    NASA Astrophysics Data System (ADS)

    France, Robert

    1992-03-01

    A sequential sampling program using previously published zoobenthos data is described for ubiquitous, cost-effective biomonitoring of the effects of lake acidification. Spring densities of the littoral amphipod Hyalella azteca are quantitatively sorted into five abundance catagories. An essential step in the a priori definition of decision criteria is the stratification of proportional densities per unit macrophyte biomass in relation to aqueous total phosphorus concentrations. Density rankings were related to lake acidity and to detailed lake-specific information on patterns of Hyalella life history and acid tolerance. Incorporation of Hyalella abundance as a potential metric for the assessment of the biological integrity of acid-sensitive waters is recommended. The temporal integration of transient changes in spring meltwater chemistry is an important rationale for the development of such biomonitoring procedures.

  12. Gas flushing through hyper-acidic crater lakes: the next steps within a reframed monitoring time window

    NASA Astrophysics Data System (ADS)

    Rouwet, Dmitri

    2016-04-01

    Tracking variations in the chemical composition, water temperature and pH of brines from peak-activity crater lakes is the most obvious way to forecast phreatic activity. Volcano monitoring intrinsically implies a time window of observation that should be synchronised with the kinetics of magmatic processes, such as degassing and magma intrusion. To decipher "how much time ago" a variation in degassing regime actually occurred before eventually being detected in a crater lake is key, and depends on the lake water residence time. The above reasoning assumes that gas is preserved as anions in the lake water (SO4, Cl, F anions), in other words, that scrubbing of acid gases is complete and irreversible. Less is true. Recent work has confirmed, by direct MultiGas measurement from evaporative plumes, that even the strongest acid in liquid medium (i.e. SO2) degasses from hyper-acidic crater lakes. The less strong acid HCl has long been recognised as being more volatile than hydrophyle in extremely acidic solutions (pH near 0), through a long-term steady increase in SO4/Cl ratios in the vigorously evaporating crater lake of Poás volcano. We now know that acidic gases flush through hyper-acidic crater lake brines, but we don't know to which extend (completely or partially?), and with which speed. The chemical composition hence only reflects a transient phase of the gas flushing through the lake. In terms of volcanic surveillance this brings the advantage that the monitoring time window is definitely shorter than defined by the water chemistry, but yet, we do not know how much shorter. Empirical experiments by Capaccioni et al. (in press) have tried to tackle this kinetic problem for HCl degassing from a "lab-lake" on the short-term (2 days). With this state of the art in mind, two new monitoring strategies can be proposed to seek for precursory signals of phreatic eruptions from crater lakes: (1) Tracking variations in gas compositions, fluxes and ratios between species in

  13. Assessment of factors limiting algal growth in acidic pit lakes--a case study from Western Australia, Australia.

    PubMed

    Kumar, R Naresh; McCullough, Clint D; Lund, Mark A; Larranaga, Santiago A

    2016-03-01

    Open-cut mining operations can form pit lakes on mine closure. These new water bodies typically have low nutrient concentrations and may have acidic and metal-contaminated waters from acid mine drainage (AMD) causing low algal biomass and algal biodiversity. A preliminary study was carried out on an acidic coal pit lake, Lake Kepwari, in Western Australia to determine which factors limited algal biomass. Water quality was monitored to obtain baseline data. pH ranged between 3.7 and 4.1, and solute concentrations were slightly elevated to levels of brackish water. Concentrations of N were highly relative to natural lakes, although concentrations of FRP (<0.01 mg/L) and C (total C 0.7-3.7 and DOC 0.7-3.5 mg/L) were very low, and as a result, algal growth was also extremely low. Microcosm experiment was conducted to test the hypothesis that nutrient enrichment will be able to stimulate algal growth regardless of water quality. Microcosms of Lake Kepwari water were amended with N, P and C nutrients with and without sediment. Nutrient amendments under microcosm conditions could not show any significant phytoplankton growth but was able to promote benthic algal growth. P amendments without sediment showed a statistically higher mean algal biomass concentration than controls or microcosms amended with phosphorus but with sediment did. Results indicated that algal biomass in acidic pit lake (Lake Kepwari) may be limited primarily by low nutrient concentrations (especially phosphorus) and not by low pH or elevated metal concentrations. Furthermore, sediment processes may also reduce the nutrient availability.

  14. Functional groups and activities of bacteria in a highly acidic volcanic mountain stream and lake in Patagonia, Argentina.

    PubMed

    Wendt-Potthoff, Katrin; Koschorreck, M

    2002-01-01

    Acidic volcanic waters are naturally occurring extreme habitats that are subject of worldwide geochemical research but have been little investigated with respect to their biology. To fill this gap, the microbial ecology of a volcanic acidic river (pH approximately equal to 0-1.6), Rio Agrio, and the recipient lake Caviahue in Patagonia, Argentina, was studied. Water and sediment samples were investigated for Fe(II), Fe(III), methane, bacterial abundances, biomass, and activities (oxygen consumption, iron oxidation and reduction). The extremely acidic river showed a strong gradient of microbial life with increasing values downstream and few signs of life near the source. Only sulfide-oxidizing and fermentative bacteria could be cultured from the upper part of Rio Agrio. However, in the lower part of the system, microbial biomass and oxygen penetration and consumption in the sediment were comparable to non-extreme aquatic habitats. To characterize similarities and differences of chemically similar natural and man-made acidic waters, our findings were compared to those from acidic mining lakes in Germany. In the lower part of the river and the lake, numbers of iron and sulfur bacteria and total biomass in sediments were comparable to those known from acidic mining lakes. Bacterial abundance in water samples was also very similar for both types of acidic water (around 10(5) mL(-1)). In contrast, Fe(II) oxidation and Fe(III) reduction potentials appeared to be lower despite higher biogenic oxygen consumption and higher photosynthetic activity at the sediment-water interface. Surprisingly, methanogenesis was detected in the presence of high sulfate concentrations in the profundal sediment of Lake Caviahue. In addition to supplementing microbiological knowledge on acidic volcanic waters, our study provides a new view of these extreme sites in the general context of aquatic habitats.

  15. High Elevation Lakes of the Western US: Are we Studying Systems Recovering from Excess Atmospheric Deposition of Acids and Nutrients?

    NASA Astrophysics Data System (ADS)

    Sickman, J. O.

    2011-12-01

    Instrumental records and monitoring of high elevation lakes began in most areas of the western US in the early 1980s. Much effort has been devoted to detecting changes in these aquatic ecosystems resulting from increased atmospheric deposition of acids and nutrients. However, there is growing evidence that thresholds for atmospheric pollutants were crossed much earlier in the 20th Century and that some of the subsequent hydrochemical and ecological changes observed in these lakes may be the result of recovery from earlier atmospheric forcing. We examine responses of high elevation lakes to atmospheric deposition on annual to century timescales using data from a 29-year study of Emerald Lake (Sequoia National Park) and paleolimnological analyses of other high elevation lakes incorporating diatom species analyses and geochemical proxies for fossil-fuel burning. At Emerald Lake, we have observed multiple transitions between nitrogen and phosphorus limitation of phytoplankton, the earliest of which occurred in the beginning of the 1980s and may be the result of reduction in N deposition due to the Clean Air Act. Critical loads analyses incorporating diatom species in lake sediments suggest that thresholds for N deposition were crossed in the period of 1950-1980 in the Rocky Mountains and likely much earlier, 1900-1920, in the Sierra Nevada. Diatom species composition is strongly controlled by acid neutralizing capacity (ANC) in the Sierra Nevada and we have observed a pronounced decline and recovery of ANC over the period of 1920-1980 in some Sierra Nevada lakes that coincides with the abundance of spheroidal carbonaceous particles (i.e., a diagnostic tracer of fossil fuel combustion) preserved in lake sediments; these patterns appear to be driven by increased emissions of oxidized N and S in the mid-20th Century and reductions in acid precursor levels caused by the Clean Air Act in the 1970s. Thus, when interpreting observational records from western high elevation

  16. Influence of bioturbation on the biogeochemistry of the sediment in the littoral zone of an acidic mine pit lake

    NASA Astrophysics Data System (ADS)

    Lagauzère, S.; Moreira, S.; Koschorreck, M.

    2010-10-01

    In the last decades, the mining exploitation of large areas in Lusatia (South-eastern Germany) but also in other mining areas worldwide has led to the formation of hundreds of pit lakes. Pyrite oxidation in the surrounding dumps makes many such lakes extremely acidic (pH < 3). The biogeochemical functioning of these lakes is mainly governed by cycling of iron. This represents a relevant ecological problem and intensive research has been conducted to understand the involved biogeochemical processes and develop bioremediation strategies. Despite some studies reporting the presence of living organisms (mostly bacteria, algae, and macro-invertebrates) under such acidic conditions, and their trophic interactions, their potential impact on the ecosystem functioning was poorly investigated. The present study aimed to assess the influence of chironomid larvae on oxygen dynamics and iron cycle in the sediment of acidic pit lakes. In the Mining Lake 111, used as a study case since 1996, Chironomus crassimanus (Insecta, Diptera) is the dominant benthic macro-invertebrate species and occurs at relatively high abundances in shallow water. A 16-day laboratory experiment using microcosms combined with high resolution measurements (DET gel probes and O2 microsensors) was carried out. The burrowing activity of C. crassimanus larvae induced a 3-fold increase of the oxygen consumption by sediment, and stimulated the mineralization of organic matter in the upper layers of the sediment. The iron cycle was also impacted (e.g. lower rates of reduction and oxidation, increase of iron-oxidizing bacteria abundance, stimulation of mineral formation) but with no significant effect on the iron flux at the sediment-water interface, and thus on the water acidity budget. This work provides the first assessment of bioturbation in an acidic mining lake and shows that its influence on biogeochemistry cannot be neglected.

  17. Influence of bioturbation on the biogeochemistry of littoral sediments of an acidic post-mining pit lake

    NASA Astrophysics Data System (ADS)

    Lagauzère, S.; Moreira, S.; Koschorreck, M.

    2011-02-01

    In the last decades, the mining exploitation of large areas in Lusatia (Eastern Germany) but also in other mining areas worldwide has led to the formation of hundreds of pit lakes. Pyrite oxidation in the surrounding dumps makes many such lakes extremely acidic (pH < 3). The biogeochemical functioning of these lakes is mainly governed by cycling of iron. This represents a relevant ecological problem and intensive research has been conducted to understand the involved biogeochemical processes and develop bioremediation strategies. Despite some studies reporting the presence of living organisms (mostly bacteria, algae, and macro-invertebrates) under such acidic conditions, and their trophic interactions, their potential impact on the ecosystem functioning was poorly investigated. The present study aimed to assess the influence of chironomid larvae on oxygen dynamics and iron cycle in the sediment of acidic pit lakes. In the Mining Lake 111, used as a study case since 1996, Chironomus crassimanus (Insecta, Diptera) is the dominant benthic macro-invertebrate species and occurs at relatively high abundances in shallow water. A 16-day laboratory experiment using microcosms combined with high resolution measurements (DET gel probes and O2 microsensors) was carried out. The burrowing activity of C. crassimanus larvae induced a 3-fold increase of the diffusive oxygen uptake by sediment, indicating a stimulation of the mineralization of organic matter in the upper layers of the sediment. The iron cycle was also impacted (e.g. lower rates of reduction and oxidation, increase of iron-oxidizing bacteria abundance, stimulation of mineral formation) but with no significant effect on the iron flux at the sediment-water interface, and thus on the water acidity budget. This work provides the first assessment of bioturbation in an acidic mining lake and shows that its influence on biogeochemistry cannot be neglected.

  18. Enrichment of Non-Terrestrial L-Proteinogenic Amino Acids by Aqueous Alteration on the Tagish Lake Meteorite Parent Body

    NASA Technical Reports Server (NTRS)

    Glavin, Daniel P.; Elsila, Jamie E.; Burton, Aaron S.; Callahan, Michael P.; Dworkin, Jason P.; Herd, Christopher D. K.

    2012-01-01

    The distribution and isotopic and enantiomeric compositions of amino acids found in three distinct fragments of the Tagish Lake C2-type carbonaceous chondrite were investigated via liquid chromatography fluorescence detection time-of-flight mass spectrometry and gas chromatography isotope ratio mass spectrometry. Large L-enantiomeric excesses (L(sub ee) approx. 43 to 59%) of the a-hydrogen aspartic and glutamic amino acids were measured in Tagish Lake, whereas alanine, another alpha-hydrogen protein amino acid, was found to be nearly racemic (D approx. L) using both techniques. Carbon isotope measurements of D- and L-aspartic acid and D- and L-alanine in Tagish Lake fall well outside of the terrestrial range and indicate that the measured aspartic acid enantioenrichment is indigenous to the meteorite. Alternate explanations for the Lexcesses of aspartic acid such as interference from other compounds present in the sample, analytical biases, or terrestrial amino acid contamination were investigated and rejected. These results can be explained by differences in the solid-solution phase behavior of aspartic acid, which can form conglomerate enantiopure solids during crystallization, and alanine, which can only form racemic crystals.

  19. 21 CFR 184.1505 - Mono- and diglycerides.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... acids that are derived from edible sources. The most prevalent fatty acids include lauric, linoleic, myristic, oleic, palmitic, and stearic. Mono- and diglycerides are manufactured by the reaction of glycerin with fatty acids or the reaction of glycerin with triglycerides in the presence of an alkaline...

  20. 21 CFR 184.1505 - Mono- and diglycerides.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... prepared from fats or oils or fat-forming acids that are derived from edible sources. The most prevalent fatty acids include lauric, linoleic, myristic, oleic, palmitic, and stearic. Mono- and diglycerides are manufactured by the reaction of glycerin with fatty acids or the reaction of glycerin with triglycerides in...

  1. 21 CFR 184.1505 - Mono- and diglycerides.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... prepared from fats or oils or fat-forming acids that are derived from edible sources. The most prevalent fatty acids include lauric, linoleic, myristic, oleic, palmitic, and stearic. Mono- and diglycerides are manufactured by the reaction of glycerin with fatty acids or the reaction of glycerin with triglycerides in...

  2. 21 CFR 184.1505 - Mono- and diglycerides.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... prepared from fats or oils or fat-forming acids that are derived from edible sources. The most prevalent fatty acids include lauric, linoleic, myristic, oleic, palmitic, and stearic. Mono- and diglycerides are manufactured by the reaction of glycerin with fatty acids or the reaction of glycerin with triglycerides in...

  3. 21 CFR 184.1505 - Mono- and diglycerides.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... prepared from fats or oils or fat-forming acids that are derived from edible sources. The most prevalent fatty acids include lauric, linoleic, myristic, oleic, palmitic, and stearic. Mono- and diglycerides are manufactured by the reaction of glycerin with fatty acids or the reaction of glycerin with triglycerides in...

  4. Critical loads of acidity for 90,000 lakes in northern Saskatchewan: A novel approach for mapping regional sensitivity to acidic deposition

    NASA Astrophysics Data System (ADS)

    Cathcart, H.; Aherne, J.; Jeffries, D. S.; Scott, K. A.

    2016-12-01

    Atmospheric emissions of sulphur dioxide (SO2) from large point sources are the primary concern for acidic deposition in western Canada, particularly in the Athabasca Oil Sands Region (AOSR) where prevailing winds may potentially carry SO2 over acid-sensitive lakes in northern Saskatchewan. A novel catchment-scale regression kriging approach was used to assess regional sensitivity and critical loads of acidity for the total lake population of northern Saskatchewan (89,947 lakes). Lake catchments were delineated using Thiessen polygons, and surface water chemistry was predicted for sensitivity indicators (calcium, pH, alkalinity, and acid neutralizing capacity). Critical loads were calculated with the steady state water chemistry model using regression-kriged base cations, sulphate, and dissolved organic carbon concentrations modelled from surface water observations (n > 800) and digital landscape-scale characteristics, e.g., climate, soil, vegetation, landcover, and geology maps. A large region (>13,726 km2) of two or more indicators of acid sensitivity (pH < 6 and acid neutralizing capacity, alkalinity, calcium < 50 μeq L-1) and low critical loads < 5 meq m-2 yr-1 were predicted on the Athabasca Basin. Exceedance of critical loads under 2006 modelled total sulphate deposition was predicted for 12% of the lakes (covering an area of 3742 km2), primarily located on the Athabasca Basin, within 100 km of the AOSR. There have been conflicting scientific reports of impacts from atmospheric emissions from the AOSR; the results of this study suggest that catchments in the Athabasca Basin within 100 km of the AOSR have received acidic deposition in excess of their critical loads and many of them may be at risk of ecosystem damage owing to their sensitivity.

  5. Holocene n-Fatty Acid Δd Records from Lake Hurleg, Northeastern Tibetan Plateau

    NASA Astrophysics Data System (ADS)

    He, Y.; Zhao, C.; Liu, Z.; Wang, H.; Liu, W.; Yu, Z.

    2014-12-01

    The interpretation of δD records from the Tibetan Plateau region remains challenging due to multiple climatic factors influencing on the precipitation isotopic values. Here we study the mechanism of δD variation in this region, by reconstructing the past 10.5 ka n-fatty acid (FA) δD records from sediment core taken in Lake Hurleg on the northeastern Tibetan Plateau and comparing them to the previously presented temperature and moisture data from the same core. Comparison of both C16 and C26 n-FA δD with the average carbon length of n-FA suggests that n-FA δD variability was independent of the n-FA distribution. For δD in the C26 n-FA, it serves as an indicator of hydrogen isotopic signals in terrestrial water. During the Holocene, the heavier C26 n-FA δD values corresponded to millennial cold and wet conditions as inferred by the temperature and salinity records. Thus the terrestrial water δD value changes might be caused by factors other than temperature and moisture, such as the vegetation type and the glacial melt water input. As for the C16 n-FA, although it contains both terrestrial and aquatic source, it mainly mimics the lacustrine water isotopic signal. Therefore, the difference between C16 and C26 n-FA δD can be interpreted as the fractionation between terrestrial and aquatic water induced by evaporation on lake surface. Based on the δD records together with temperature and moisture records, we suggest in millennial timescale, not only stronger precipitation but also less evaporation occurred during the cold periods in the Lake Hurleg region.

  6. The 2005 catastrophic acid crater lake drainage, lahar, and acidic aerosol formation at Mount Chiginagak volcano, Alaska, USA: Field observations and preliminary water and vegetation chemistry results

    NASA Astrophysics Data System (ADS)

    Schaefer, Janet R.; Scott, William E.; Evans, William C.; Jorgenson, Janet; McGimsey, Robert G.; Wang, Bronwen

    2008-07-01

    A mass of snow and ice 400-m-wide and 105-m-thick began melting in the summit crater of Mount Chiginagak volcano sometime between November 2004 and early May 2005, presumably owing to increased heat flux from the hydrothermal system, or possibly from magma intrusion and degassing. In early May 2005, an estimated 3.8 × 106 m3 of sulfurous, clay-rich debris and acidic water, with an accompanying acidic aerosol component, exited the crater through a tunnel at the base of a glacier that breaches the south crater rim. Over 27 km downstream, the acidic waters of the flood inundated an important salmon spawning drainage, acidifying Mother Goose Lake from surface to depth (approximately 0.5 km3 in volume at a pH of 2.9 to 3.1), killing all aquatic life, and preventing the annual salmon run. Over 2 months later, crater lake water sampled 8 km downstream of the outlet after considerable dilution from glacial meltwater was a weak sulfuric acid solution (pH = 3.2, SO4 = 504 mg/L, Cl = 53.6 mg/L, and F = 7.92 mg/L). The acid flood waters caused severe vegetation damage, including plant death and leaf kill along the flood path. The crater lake drainage was accompanied by an ambioructic flow of acidic aerosols that followed the flood path, contributing to defoliation and necrotic leaf damage to vegetation in a 29 km2 area along and above affected streams, in areas to heights of over 150 m above stream level. Moss species killed in the event contained high levels of sulfur, indicating extremely elevated atmospheric sulfur content. The most abundant airborne phytotoxic constituent was likely sulfuric acid aerosols that were generated during the catastrophic partial crater lake drainage event. Two mechanisms of acidic aerosol formation are proposed: (1) generation of aerosol mist through turbulent flow of acidic water and (2) catastrophic gas exsolution. This previously undocumented phenomenon of simultaneous vegetation-damaging acidic aerosols accompanying drainage of an acidic

  7. The 2005 catastrophic acid crater lake drainage, lahar, and acidic aerosol formation at Mount Chiginagak volcano, Alaska, USA: Field observations and preliminary water and vegetation chemistry results

    USGS Publications Warehouse

    Schaefer, J.R.; Scott, W.E.; Evans, William C.; Jorgenson, J.; McGimsey, R.G.; Wang, B.

    2008-01-01

    A mass of snow and ice 400-m-wide and 105-m-thick began melting in the summit crater of Mount Chiginagak volcano sometime between November 2004 and early May 2005, presumably owing to increased heat flux from the hydrothermal system, or possibly from magma intrusion and degassing. In early May 2005, an estimated 3.8??106 m3 of sulfurous, clay-rich debris and acidic water, with an accompanying acidic aerosol component, exited the crater through a tunnel at the base of a glacier that breaches the south crater rim. Over 27 km downstream, the acidic waters of the flood inundated an important salmon spawning drainage, acidifying Mother Goose Lake from surface to depth (approximately 0.5 km3 in volume at a pH of 2.9 to 3.1), killing all aquatic life, and preventing the annual salmon run. Over 2 months later, crater lake water sampled 8 km downstream of the outlet after considerable dilution from glacial meltwater was a weak sulfuric acid solution (pH = 3.2, SO4 = 504 mg/L, Cl = 53.6 mg/L, and F = 7.92 mg/L). The acid flood waters caused severe vegetation damage, including plant death and leaf kill along the flood path. The crater lake drainage was accompanied by an ambioructic flow of acidic aerosols that followed the flood path, contributing to defoliation and necrotic leaf damage to vegetation in a 29 km2 area along and above affected streams, in areas to heights of over 150 m above stream level. Moss species killed in the event contained high levels of sulfur, indicating extremely elevated atmospheric sulfurcontent. The most abundant airborne phytotoxic constituent was likely sulfuric acid aerosols that were generated during the catastrophic partial crater lake drainage event. Two mechanisms of acidic aerosol formation are proposed: (1) generation of aerosol mist through turbulent flow of acidic water and (2) catastrophic gas exsolution. This previously undocumented phenomenon of simultaneous vegetationdamaging acidic aerosols accompanying drainage of an acidic crater

  8. Removal of emerging perfluorooctanoic acid and perfluorooctane sulfonate contaminants from lake water.

    PubMed

    Pramanik, Biplob Kumar; Pramanik, Sagor Kumar; Sarker, Dipok Chandra; Suja, Fatihah

    2016-10-11

    Perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) are the major polyfluoroalkyl substances (PFASs) contaminating global water environment. This study investigated the efficiency of granular activated carbon (GAC), ultrafiltration (UF) and nanofiltration (NF) treatment for removing PFOS and PFOA contaminants from lake water. NF gave greater removal of all contaminant types (in terms of organic matter, PFOS and PFOA) than GAC treatment which in turn was greater than UF treatment. The lower removal by UF was due to larger pore size of the membrane compared to the size of the target contaminants. For all treatment processes, lower pH (4) in the feedwater showed greater rejection of the organics and selected PFASs. This was likely due to increase in the electrostatic repulsion between solute and sorbent. It could be observed that on increasing the concentration of organics in the feed solution, the rejection of PFOA/PFOS decreased which was due to competition between organics and PFOS/PFOA for binding sites on the membrane/activated carbon surface. It was also noted that protein content led to greater influence for lower rejection of the PFOA/PFOS than carbohydrate or DOC content. This study demonstrated the potential use of membrane processes for removing emerging persistent organic pollutant removal from lake water.

  9. Phytoplankton limitation by phosphorus and zooplankton grazing in an acidic Adirondack lake

    SciTech Connect

    Singer, R.; Evans, G.L.; Pratt, N.C.

    1984-08-01

    Lakes which are believed to have been acidified by atmospheric deposition of anthropogenic substances are known for their unusually high water clarity and low nutrient concentrations. Some evidence indicates that alterations in predator/prey relationships, an indirect effect of acidification, bring about the increase in water clarity. Enclosures were used to study the effects of phosphorus addition and zooplankton removal on the phytoplankton of an acidic lake in the Adirondack Mountains of New York. Fertilized enclosures had significantly lower alkalinities and contained significantly more dissolved oxygen after the incubation period than did unfertilized enclosures. The P concentration remained at or near the limit of detection in the unfertilized enclosures. The phytoplankton population bloomed after the addition of 80 micro g/liter of phosphate as KH/sub 2/PO/sub 4/. The response was measured by cell counts of the dominant phytoplankton. Chlamydomonas, and by changes in chlorophyll a concentration. About half the number of algal cells were present after the two week incubation when zooplankton were not removed, indicating that zooplankton herbivory can influence, but not totally control, the algal production. 46 references.

  10. Influence of in ovo mercury exposure, lake acidity, and other factors on common loon egg and chick quality in Wisconsin

    USGS Publications Warehouse

    Kenow, Kevin P.; Meyer, Michael W.; Rossmann, Ronald; Gray, Brian R.; Arts, Michael T.

    2015-01-01

    A field study was conducted in Wisconsin (USA) to characterize in ovo mercury (Hg) exposure in common loons (Gavia immer). Total Hg mass fractions ranged from 0.17 mg/g to 1.23mg/g wet weight in eggs collected from nests on lakes representing a wide range of pH (5.0–8.1) and were modeled as a function of maternal loon Hg exposure and egg laying order. Blood total Hg mass fractions in a sample of loon chicks ranged from 0.84ug/g to 3.86 ug/g wet weight at hatch. Factors other than mercury exposure that may have persistent consequences on development of chicks from eggs collected on low-pH lakes (i.e., egg selenium, calcium, and fatty acid mass fractions) do not seem to be contributing to reported differences in loon chick quality as a function of lake pH. However, it was observed that adult male loons holding territories on neutral-pH lakes were larger on average than those occupying territories on low-pH lakes. Differences in adult body size of common loons holding territories on neutral-versus low-pH lakes may have genetic implications for differences in lake-source-related quality (i.e., size) in chicks. The tendency for high in ovo Hg exposure and smaller adult male size to co-occur in low-pH lakes complicates the interpretation of the relative contributions of each to resulting chick quality.

  11. How Long Is Mono Contagious?

    MedlinePlus

    ... it is contagious. Once someone gets mono, the virus stays in that person's body for life. That doesn't mean that you are always ... as long as 18 months. After that, the virus remains dormant (inactive) in the body for the rest of a person's life. If you've had mono, the virus can ...

  12. Mono-estolide synthesis from trans-8-hydroxy fatty acids by lipases in solvent-free media and their physical properties

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pseudomonas aeruginosa 42A2 is known to produce two hydroxy-fatty acids, 10(S)-hydroxy-8(E)-octadecenoic and 7,10(S,S)-dihydroxy-8(E)-octadecenoic acids, when cultivated in a mineral medium using oleic acid as a single carbon source. These compounds were purified, 91 and 96 % respectively, to produc...

  13. Hydrological Evolution and Chemical Structure of the Hyper-acidic Spring-lake System on White Island, New Zealand

    NASA Astrophysics Data System (ADS)

    Christenson, B. W.; Britten, K.; Mazot, A.

    2015-12-01

    White Island has a long and varied history of acid spring discharge and shallow ephemeral lake formation on the Main Crater floor. In the 12 months prior to the onset of the 1976-2000 eruptive episode, mass discharge from the spring system increased ca. 10-fold, pointing to a strong coupling of the hydrothermal environment to the evolving magmatic system. However, between 1976-1978 the formation of numerous eruption vents to 200 m depth in the Western Sub-crater abruptly changed the hydrostatic regime of the volcano, resulting in the reversal of groundwater flow in the massif towards the newly-formed crater(s). This affected not only the style of volcanic activity (leading to phreatic-phreatomagmatic-magmatic eruption cycles), but also led to the demise of the spring system, with total flow from the crater declining by a factor > 100 by 1979. Eruptive activity came to a close soon after moderate Strombolian activity in mid-2000, by which time ephemeral lakes had already started to form in the eruption crater complex. Since 2003 there have been two complete lake filling and evaporative cycles, reflecting varying heat flow through the conduit system beneath the lake. Over these cycles, lake water concentrations of Cl and SO4 varied between ca. 35-150 and 5-45 g/L respectively, with pH values ranging between +1.5 and -1. Springs reappeared on the Main Crater floor in 2004, and their discharges varied with lake level, pointing to the lake level being a primary control over the piezometric surface in the crater area. Springs closest to the crater complex show direct evidence of crater lake water infiltration into the crater floor aquifer, whereas distal spring discharges show compositional variations reflecting vertical displacement of the interface between shallow, dilute condensate and an underlying acidic brine fluid. Evidence suggests that this acidic brine presently contains a significant component of altered seawater. Volcanic unrest in 2012, which included

  14. Indications of human activity from amino acid and amino sugar analyses on Holocene sediments from lake Lonar, central India

    NASA Astrophysics Data System (ADS)

    Menzel, P.; Gaye, B.; Wiesner, M.; Prasad, S.; Basavaiah, N.; Stebich, M.; Anoop, A.; Riedel, N.; Brauer, A.

    2012-04-01

    The DFG funded HIMPAC (Himalaya: Modern and Past Climates) programme aims to reconstruct Holocene Indian Monsoon climate using a multi-proxy and multi-archive approach. First investigations made on sediments from a ca. 10 m long core covering the whole Holocene taken from the lake Lonar in central India's state Maharashtra, Buldhana District, serve to identify changes in sedimentation, lake chemistry, local vegetation and regional to supra-regional climate patterns. Lake Lonar occupies the floor of an impact crater that formed on the ~ 65 Ma old basalt flows of the Deccan Traps. It covers an area of ca. 1 km2 and is situated in India's core monsoon area. The modern lake has a maximum depth of about 5 m, is highly alkaline, and hyposaline, grouped in the Na-Cl-CO3 subtype of saline lakes. No out-flowing stream is present and only three small streams feed the lake, resulting in a lake level highly sensitive to precipitation and evaporation. The lake is eutrophic and stratified throughout most of the year with sub- to anoxic waters below 2 m depth. In this study the core sediments were analysed for their total amino acid (AA) and amino sugar (AS) content, the amino acid bound C and N percentage of organic C and total N in the sediment and the distribution of individual amino acids. The results roughly show three zones within the core separated by distinct changes in their AA content and distribution. (i) The bottom part of the core from ca. 12000 cal a BP to 11400 cal a BP with very low AA and AS percentage indicating high lithogenic contribution, most probably related to dry conditions. (ii) From 11400 cal a BP to 1200 cal a BP the sediments show moderate AA and AS percentages and low values for the ratios of proteinogenic AAs to their non-proteinogenic degradation products (e.g. ASP/β-ALA; GLU/γ-ABA). (iii) The top part of the core (< 1200 cal a BP) is characterised by an intense increase in total AA and AS, AA-C/Corg and AA-N/Ntotas well as in the ratio of

  15. Water Resources Data, California Water Year 1982, Volume 1. Southern Great Basin from Mexican Border to Mono Lake basin, and Pacific slope basins from Tijuana River to Santa Maria River

    USGS Publications Warehouse

    Bowers, J.C.; Butcher, M.T.; Lamb, C.E.; Singer, J.A.; Smith, G.B.

    1984-01-01

    Water-resources data for the 1982 water year for California consists of records of stage, discharge, and water quality of streams; stage and contents of lakes and reservoirs; and water levels and water quality in wells. Volume 1 contains discharge records for 160 gaging stations; stage and contents for 19 lakes and reservoirs; water quality for 20 streams and 20 wells; water levels for 174 observation wells. Also included are 10 crest-stage partial-record stations. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in California.

  16. Water Resources Data for California, water year 1981: Vol. 1. Colorado River basin, Southern Great basin from Mexican Border to Mono Lake basin, and Pacific slope basins from Tijuana River to Santa Maria River

    USGS Publications Warehouse

    ,

    1982-01-01

    Water-resources data for the 1981 water year for California consists of records of stage, discharge, and water quality of streams; stage and contents in lakes and reservoirs; and water levels and water quality in wells. Volume 1 contains discharge records for 169 gaging stations; stage and contents for 19 lakes and reservoirs; water quality for 42 streams and 21 wells; water levels for 169 observation wells. Also included are 10 crest-stage partial-record stations. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in California.

  17. Water Resources Data for California, Water Year 1988. Volume 1. Southern Great Basin from Mexican Border to Mono Lake Basin, and Pacific Slope Basins from Tijuana River to Santa Maria River

    USGS Publications Warehouse

    Polinoski, K.G.; Hoffman, E.B.; Smith, G.B.; Bowers, J.C.

    1989-01-01

    Water resources data for the 1988 water year for California consist of records of stage, discharge, and water quality of streams; stage and contents in lakes and reservoirs; and water levels and water quality in wells. Volume 1 contains discharge records for 134 gaging stations; stage and contents for 17 lakes and reservoirs; and water quality for 24 streams. Also included are 10 crest-stage partial-record stations, 5 miscellaneous measurement sites, and 16 water-quality partial-record stations. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in California.

  18. Water resources data for California, water year 1980; Volume 1, Colorado River basin, Southern Great Basin from Mexican border to Mono Lake basin, and Pacific slope basins from Tijuana River to Santa Maria River

    USGS Publications Warehouse

    ,

    1981-01-01

    Volume 1 of water resources data for the 1980 water year for California consists of records of stage, discharge, and water quality of streams; stage and contents in lake and reservoirs; and water levels in wells. This report contains discharge records for 174 gaging stations; stage and contents for 18 lakes and reservoirs; water quality for 51 stations; water levels for 165 observation wells. Also included are 9 crest-stage partial-record stations. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in California.

  19. Water Resources Data for California, Water Year 1987. Volume 1. Southern Great Basin from Mexican Border to Mono Lake Basin, and Pacific Slope Basins from Tijuana River to Santa Maria River

    USGS Publications Warehouse

    Bowers, J.C.; McConaughy, C.E.; Polinoski, K.G.; Smith, G.B.

    1988-01-01

    Water resources data for the 1987 water year for California consist of records of stage, discharge, and water quality of streams; stage and contents in lakes and reservoirs; and water levels and water quality in wells. Volume 1 contains discharge records for 134 gaging stations; stage and contents for 16 lakes and reservoirs; and water quality for 16 streams. Also included are 10 crest-stage partial-record stations, 3 miscellaneous measurement sites, and 10 water-quality partial-record stations. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in California.

  20. Water Resources Data for California, 1983. Volume 1. Southern Great Basin from Mexican Border to Mono Lake Basin, and Pacific Slope Basins from Tijuana River to Santa Maria River

    USGS Publications Warehouse

    Bowers, J.C.; Butcher, M.T.; Lamb, C.E.; Singer, J.A.; Smith, G.B.

    1985-01-01

    Water resources data for the 1983 water year for California consists of records of stage, discharge, and water quality of streams; stage and contents in lakes and reservoirs; and water levels and water quality in wells. Volume 1 contains discharge records for 154 gaging stations; stage and contents for 18 lakes and reservoirs; water quality for 20 streams and 18 wells; water levels for 165 observation wells. Also included are 10 crest-stage partial-record stations. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and federal agencies in California.

  1. Water Resources Data for California, Water Year 1985. Volume 1. Southern Great Basin from Mexican Border to Mono Lake Basin, and Pacific Slope Basins from Tijuana River to Santa Maria River

    USGS Publications Warehouse

    Bowers, J.C.; McConaughy, C.E.; Polinoski, K.G.; Smith, G.B.

    1987-01-01

    Water resources data for the 1985 water year for California consists of records of stage, discharge, and water quality of streams; stage and contents in lakes and reservoirs; and water levels and water quality in wells. Volume 1 contains discharge records for 150 gaging stations; stage and contents for 17 lakes and reservoirs; water quality for 23 streams. Also included are 10 crest-stage partial-record stations, three miscellaneous measurement sites, and one waterquality partial-record station. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in California.

  2. Water Resources Data for California, Water Year 1986. Volume 1. Southern Great Basin from Mexican Border to Mono Lake Basin, and Pacific Slope Basins from Tijuana River to Santa Maria River

    USGS Publications Warehouse

    Bowers, J.C.; McConaughy, C.E.; Polinoski, K.G.; Smith, G.B.

    1988-01-01

    Water resources data for the 1986 water year for California consist of records of stage, discharge, and water quality of streams; stage and contents in lakes and reservoirs; and water levels and water quality in wells. Volume 1 contains discharge records for 144 gaging stations; stage and contents for 15 lakes and reservoirs; watet quality for 21 streams. Also included are crest-stage partial-record stations, 3 miscellaneous measurement sites, and 5 water-quality partial-record stations. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in California.

  3. Binding characteristics of Cu(2+) to natural humic acid fractions sequentially extracted from the lake sediments.

    PubMed

    He, En; Lü, Changwei; He, Jiang; Zhao, Boyi; Wang, Jinghua; Zhang, Ruiqing; Ding, Tao

    2016-11-01

    Humic acids (HAs) determine the distribution, toxicity, bioavailability, and ultimate fate of heavy metals in the environment. In this work, ten HA fractions (F1-F10) were used as adsorbent, which were sequentially extracted from natural sediments of Lake Wuliangsuhai, to investigate the binding characteristics of Cu(2+) to HA. On the basis of the characterization results, differences were found between the ten extracted HA fractions responding to their elemental compositions and acidic functional groups. The characterization results reveal that the responses of ten extracted HA fractions to their elemental compositions and acidic functional groups were different. The O/C and (O + N)/C ratio of F1-F8 approximately ranged from 0.66 to 0.53 and from 0.72 to 0.61, respectively; the measured results showed that the contents of phenolic groups and carboxyl groups decreased from 4.46 to 2.60 mmol/g and 1.60 to 0.58 mmol/g, respectively. The binding characteristics of Cu(2+) to the ten HA fractions were well modeled by the bi-Langmuir model; the binding behavior of Cu(2+) to all the ten HA fractions were strongly impacted by pH and ionic strength. The FTIR and SEM-EDX image of HA fractions (pre- and post-adsorption) revealed that carboxyl and phenolic groups were responsible for the Cu(2+) sorption on the ten sequentially extracted HA fractions process, which is the same with the analysis of the ligand binding and bi-Langmuir models Accordingly, the adsorption capacity of the former HA fractions on Cu(2+) were higher than the latter ones, which may be attributed to the difference of carboxyl and phenolic group contents between the former and latter extracted HA fractions. Additionally, the functional groups with N and S should not be neglected. This work is hopeful to understand the environmental effect of humic substances, environmental geochemical behavior, and bioavailability of heavy metals in lakes.

  4. Influence of Acid Mine Drainage (AMD) on recent phyto- and zooplankton in "the Anthropogenic Lake District" in south-west Poland

    NASA Astrophysics Data System (ADS)

    Sienkiewicz, Elwira; Gasiorowski, Michal

    2015-04-01

    In south-west Poland (central Europe) many the post-mining lakes formed so-called "the Anthropogenic Lake District". Areas, where water comes in contact with lignite beds characterized by high concentration of sulfide minerals are called Acid Mine Drainage (AMD). Pyrite oxidation and other sulfide compounds caused release sulfuric acids and heavy metal ions. These processes caused decline of water pH, sometimes to extremely low pH < 2.8. Presently, pit lakes located in south-west Poland have water pH ranged between 2.7 and 8.9. Differences of water reaction in the mine lakes depend on many factors, such as bedrock buffer capacity, geological structure of carboniferous area, exploitation technique of lignite, methods of filling and water supply of reservoirs and their age. During the evolution of lakes' ecosystems, sulfate-iron-calcium type of waters occurring in acid lakes will transform in alkaline hydrogen-carbonate-calcium type of waters. Due to the different time of the completion of lignite exploitation, lakes' age varied between forty and over one hundred years. Studies showed that younger lakes are more acidic in compare to older. To estimate impact of AMD we analyzed recent diversity of diatoms and Cladocera remains and water chemistry from extremely acidic, relatively young lakes and from alkaline, older water bodies. As we expected, flora and fauna from acidic lakes have shown very low diversity and species richness. Among diatoms, Eunotia exigua (Bréb. ex Kütz.) Rabenhorst and/or E. paludosa Grunow were dominated taxa, while fauna Cladocera did not occurred in lakes with water pH < 3. On this area, exploitation of lignite continued up to 1973. Older lakes were formed in the region where the mine started work in 1880 and lignite mining stopped in 1926. Measurements of pH value in situ point to neutral or alkaline water, but because of the possibility of hysteresis phenomenon, the studies of phyto- and zooplankton have shown if there has already been a

  5. Indirect effects of UV radiation: Fe{sup 2+} enrichment stimulates picocyanobacterial growth in Clearwater acidic Shield lakes

    SciTech Connect

    Auclair, J.C.

    1995-12-31

    Ozone depletion and associated increases in UVB radiation could increase the photoreduction of iron in Shield lakes of the Boreal forest zone. Since photoreduced iron (I) is more soluble than iron (III), and the re-oxidation rate slower in acidic (pH = 5--6) lakes, phytoplankton growth and/or species composition may be altered where iron is growth limiting. The differential enrichment of UV{sub A+B} transparent herbivore-free (< 65 mu) lakewater enclosures ({approximately}500L) with phosphorus, phosphorus and Fe (II) and phosphorus, ammonium and Fe (II) revealed that the Spring phytoplankton abundance of an oligotrophic Clearwater acidic Canadian Shield lake was limited by herbivore grazing, rather than by a limiting nutrient. However, in the herbivore-free enriched enclosures the addition of Fe{sup 2+} greatly stimulated picocyanobacterial growth and grazing activity by mixotrophic species comprising the microbial food web of this lake. In spite of a 10-fold increase in the mixotrophic chrysophytes, the authors did not discern any strong competitive interactions among the mixotrophic organisms, strongly suggesting that the latter obtain most if not all of their iron quota from their picoplanktonic prey.

  6. Drainage reversals in Mono Basin during the late pliocene and Pleistocene

    USGS Publications Warehouse

    Reheis, M.C.; Stine, S.; Sarna-Wojcicki, A. M.

    2002-01-01

    Mono Basin, on the eastern flank of the central Sierra Nevada, is the highest of the large hydrographically closed basins in the Basin and Range province. We use geomorphic features, shoreline deposits, and basalt-filled paleochannels to reconstruct an early to middle Pleistocene record of shorelines and changing spillways of Lake Russell in Mono Basin. During this period of time, Lake Russell repeatedly attained altitudes between 2205 and 2280 m-levels far above the present surface of Mono Lake (~1950 m) and above its last overflow level (2188 m). The spill point of Lake Russell shifted through time owing to late Tertiary and Quaternary faulting and volcanism. During the early Pleistocene, the lake periodically discharged through the Mount Hicks spillway on the northeastern rim of Mono Basin and flowed northward into the Walker Lake drainage basin via the East Walker River. Paleochannels recording such discharge were incised prior to 1.6 Ma, possibly between 1.6 and 1.3 Ma, and again after 1.3 Ma (ages of basaltic flows that plugged the paleochannels). Faulting in the Adobe Hills on the southeastern margin of the basin eventually lowered the rim in this area to below the altitude of the Mount Hicks spillway. Twice after 0.76 Ma, and possibly as late as after 0.1 Ma, Lake Russell discharged southward through the Adobe Hills spillway into the Owens-Death Valley system of lakes. This study supports a pre-Pleistocene aquatic connection through Mono Basin between the hydrologically distinct Lahontan and Owens-Death Valley systems, as long postulated by biologists, and also confirms a probable link during the Pleistocene for species adapted to travel upstream in fast-flowing water.

  7. Limits of detections for the determination of mono- and dicarboxylic acids using gas and liquid chromatographic methods coupled with mass spectrometry

    PubMed Central

    Št’ávová, Jana; Beránek, Josef; Nelson, Eric P.; Diep, Bonnie A.; Kubátová, Alena

    2011-01-01

    The chromatographic separation and instrumental limits of detection (LODs) were obtained for a broad range of C1-C18 monocarboxylic (MCAs) and C2-C14 dicarboxylic acids (DCAs) employing either chemical derivatization followed by gas chromatography-mass spectrometry and flame ionization detection (GC-MS/FID) or direct analysis with liquid chromatography high resolution MS and tandem MS (LC-MS). Suitability, efficiency and stability of reaction products for several derivatization agents used for esterification (BF3/butanol), and trimethysilylation, including trimethylsilyl-N-N-dimethylcarbamate (TMSDMC) and N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA) were evaluated. The lowest limits of detection for the majority of compounds below 10 pg (with the exception of acetic acid) were obtained for derivatization with BF3/butanol followed by GC-MS in the total ion current (TIC) mode. Further improvements were achieved when applying either selected ion monitoring (SIM), which decreased the LODs to 1–4 pg or a combination of SIM and TIC (SITI) (2–5 pg). GC-FID provided LODs comparable to those obtained by GC-MS TIC. Both trimethylsilylation (followed by GC-MS) and direct LC-MS/MS analysis yielded LODs of 5– 40 pg for most of the acids. For volatile acids the LODs were higher, e.g., 25 and 590 ng for TMSDMC and BSTFA derivatized formic acid, respectively whereas the LC-MS methods did not allow for the analysis of formic acid at all. PMID:21185238

  8. MonoColor CMOS sensor

    NASA Astrophysics Data System (ADS)

    Wang, Ynjiun P.

    2009-02-01

    A new breed of CMOS color sensor called MonoColor sensor is developed for a barcode reading application in AIDC industry. The RGBW color filter array (CFA) in a MonoColor sensor is arranged in a 8 x 8 pixels CFA with only 4 pixels of them are color (RGB) pixels and the rest of 60 pixels are transparent or monochrome. Since the majority of pixels are monochrome, MonoColor sensor maintains 98% barcode decode performance compared with a pure monochrome CMOS sensor. With the help of monochrome and color pixel fusion technique, the resulting color pictures have similar color quality in terms of Color Semantic Error (CSE) compared with a Bayer pattern (RGB) CMOS color camera. Since monochrome pixels are more sensitive than color pixels, a MonoColor sensor produces in general about 2X brighter color picture and higher luminance pixel resolution.

  9. A microbial arsenic cycle in sediments of an acidic mine impoundment: Herman Pit, Clear Lake, California

    USGS Publications Warehouse

    Blum, Jodi S.; McCann, Shelley; Bennett, S.; Miller, Laurence G.; Stolz, J. R.; Stoneburner, B.; Saltikov, C.; Oremland, Ronald S.

    2015-01-01

    The involvement of prokaryotes in the redox reactions of arsenic occurring between its +5 [arsenate; As(V)] and +3 [arsenite; As(III)] oxidation states has been well established. Most research to date has focused upon circum-neutral pH environments (e.g., freshwater or estuarine sediments) or arsenic-rich “extreme” environments like hot springs and soda lakes. In contrast, relatively little work has been conducted in acidic environments. With this in mind we conducted experiments with sediments taken from the Herman Pit, an acid mine drainage impoundment of a former mercury (cinnabar) mine. Due to the large adsorptive capacity of the abundant Fe(III)-rich minerals, we were unable to initially detect in solution either As(V) or As(III) added to the aqueous phase of live sediment slurries or autoclaved controls, although the former consumed added electron donors (i.e., lactate, acetate, hydrogen), while the latter did not. This prompted us to conduct further experiments with diluted slurries using the live materials from the first incubation as inoculum. In these experiments we observed reduction of As(V) to As(III) under anoxic conditions and reduction rates were enhanced by addition of electron donors. We also observed oxidation of As(III) to As(V) in oxic slurries as well as in anoxic slurries amended with nitrate. We noted an acid-tolerant trend for sediment slurries in the cases of As(III) oxidation (aerobic and anaerobic) as well as for anaerobic As(V) reduction. These observations indicate the presence of a viable microbial arsenic redox cycle in the sediments of this extreme environment, a result reinforced by the successful amplification of arsenic functional genes (aioA, and arrA) from these materials.

  10. Comprehensive Emerging Chemical Discovery: Novel Polyfluorinated Compounds in Lake Michigan Trout.

    PubMed

    Fakouri Baygi, Sadjad; Crimmins, Bernard S; Hopke, Philip K; Holsen, Thomas M

    2016-09-06

    A versatile screening algorithm capable of efficiently searching liquid chromatographic/mass spectrometric data for unknown compounds has been developed using a combination of open source and generic computing software packages. The script was used to search for select novel polyfluorinated contaminants in Great Lakes fish. However, the framework is applicable whenever full-scan, high-resolution mass spectral and chromatographic data are collected. Target compound classes are defined and a matrix of candidates is generated that includes mass spectral profiles and likely fragmentation pathways. The initial calibration was performed using a standard solution of known linear perfluoroalkyl acids. Once validated, Lake Michigan trout data files were analyzed for polyfluoroalkyl acids using the algorithm referencing 3570 possible compounds including C4-C10 perfluoro- and polyfluoroalkyl, polyfluorochloroalkyl acids and sulfonates, and potential ether forms. The results suggest the presence of 30 polyfluorinated chemical formulas which have not been previously reported in the literature. The identified candidates included mono- to hexafluoroalkyl carboxylic acids, mono- and trifluoroalkyl carboxylic acid ethers, and novel polyfluoroalkyl sulfonates. Candidate species identified in lake trout were qualified using theoretical isotopic profile matching, characteristic fragmentation patterns based on known linear perfluoroalkyl acid (PFAA) fragmentation, and retention time reproducibility among replicate extractions and injections. In addition, the relative retention times of multiple species within a compound class were compared based on theoretical octanol-water partition coefficients.

  11. Perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA): emerging contaminants of increasing concern in fish from Lake Varese, Italy.

    PubMed

    Squadrone, S; Ciccotelli, V; Prearo, M; Favaro, L; Scanzio, T; Foglini, C; Abete, M C

    2015-07-01

    Perfluoroalkylated substances (PFASs) are highly fluorinated aliphatic compounds with high thermal and chemical stability, used in a range of industrial applications. Extensive screening analyses in biota samples from all over the world have shown the bioaccumulation of PFAS into higher trophic levels in the food chain. Perfluorooctane sulfonic acid (PFOS) and perfluoroctanoic acid (PFOA) are potential reproductive and developmental toxicants and are considered to be emerging endocrine disrupters. Ingestion of fish and other seafood is considered the main source of exposure of these contaminants. Here, we quantified PFOS and PFOA by LC-MS/MS in muscle samples of European perch from Lake Varese, Italy. PFOS was detected in all samples with concentrations of up to 17.2 ng g(-1). Although the reported values were lower than the recommended total daily intake (TDI) proposed by the European Food Safety Authority (EFSA), fish from Lake Varese may be a significant source of dietary PFOS exposure.

  12. Gas exchange rates for three closed-basin lakes

    SciTech Connect

    Peng, T.H.; Broecker, W.

    1980-09-01

    Long term monitoring of the /sup 14/C:/sup 12/C ratio in three closed-basin lakes in the western United States has resulted in reliable estimates of the mean CO/sub 2/ invasion rates. When normalized to sea level pressure the results are 6 mol m/sup -/2 yr/sup -/1 for Pyramid Lake, 17 for Walker Lake, and 38 for Mono Lake. Except for Mono Lake, these bomb /sup 14/C-derived invasion rates are consistent with those derived from the distribution of natural radiocarbon. The big difference in the invasion rates estimated for Mono Lake by the two methods is attributed to the influx of /sup 14/C-free spring waters to the lake. Possible causes for the difference in CO/sub 2/ invasion rates among the three lakes are wind velocity, salinity, and pH.

  13. Water Resources Data--California, Water Year 2002, Volume 1, Southern Great Basin from Mexican Border to Mono Lake Basin, and Pacific Slope Basins from Tijuana River to Santa Maria River

    USGS Publications Warehouse

    Rockwell, G.L.; Pope, G.L.; Agajanian, J.; Caldwell, L.A.

    2003-01-01

    Water-resources data for the 2002 water year for California consist of records of stage, discharge, and water quality of streams, stage and contents in lakes and reservoirs, and water levels and water quality in wells. Volume 1 contains discharge records for 188 gaging stations and 10 crest-stage partial-record stations, stage and contents for 19 lakes and reservoirs, gage-height records for 2 stations, water quality for 39 streamflow-gaging stations and 11 partial-record stations, and precipitation data for 1 station. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in California.

  14. Water Resources Data, California, Water Year 1991. Volume 1. Southern Great Basin from Mexican Border to Mono Lake Basin; and Pacific Slope Basins from Tijuana River to Santa Maria River

    USGS Publications Warehouse

    Jensen, R.M.; Hoffman, E.B.; Bowers, J.C.; Mullen, J.R.

    1992-01-01

    Water resources data for the 1991 water year for California consist of records of stage, discharge, and water quality of streams; stage and contents in lakes and reservoirs; and water levels and water quality in wells. Volume 1 contains dischrage records for 171 streamflow-gaging stations, 16 crest-stage partial-record streamflow stations, and 3 miscellaneous measurement stations; stage and contents records for 24 lakes and reservoirs; water-quality records for 23 streamflow-gaging stations, 4 partial-record stations; and precipitation records for 16 stations. These data represent that part of the National Water Data System operated by the U,S. Geological Survey and cooperating State and Federal agencies in California.

  15. Water Resources Data, California, Water Year 1994. Volume 1. Southern Great Basin from Mexican Border to Mono Lake Basin, and Pacific Slope Basins from Tijuana River to Santa Maria River

    USGS Publications Warehouse

    Hayes, P.D.; Agajanian, J.A.; Rockwell, G.L.

    1995-01-01

    Water resources data for the 1994 water year for California consist of records of stage, discharge, and water quality of streams; stage and contents in lakes and reservoirs; and water levels and water quality in wells. Volume 1 contains (1) discharge records for 143 streamflow-gaging stations, 15 crest-stage partial-record streamflow stations; (2) stage and contents records for 20 lakes and reservoirs; (3) water quality records for 19 streamflow-gaging stations and 2 partial-record stations; and ( 4) precipitation records for 8 stations. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in California.

  16. Water Resources Data, California, Water Year 1996. Volume 1. Southern Great Basin from Mexican Border to Mono Lake Basin, and Pacific Slope Basins from Tijuana River to Santa Maria River

    USGS Publications Warehouse

    Rockwell, G.L.; Hayes, P.D.; Agajanian, J.A.

    1997-01-01

    Water-resources data for the 1996 water year for California consist of records of stage, discharge, and water quality of streams, stage and contents in lakes and reservoirs, and water levels and water quality in wells. Volume 1 contains discharge records for 149 gaging stations and 6 crest-stage partial-record stations, stage and contents for 21 lakes and reservoirs, gage height records for 1 station, water quality for 19 streamflow-gaging stations and 17 partial record stations, and precipitation data for 4 stations. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in California.

  17. Water Resources Data, California, Water Year 1989. Volume 1. Southern Great Basin from Mexican Border to Mono Lake Basin; and Pacific Slope Basins from Tijuana River to Santa Maria River

    USGS Publications Warehouse

    Hoffman, E.B.; Bowers, J.C.; Jensen, R.M.

    1990-01-01

    Water resources data for the 1989 water year for California consist of records of stage, discharge, and water quality of streams; stage and contents in lakes and reservoirs; and water levels and water quality in wells. Volume 1 contains discharge records for 137 gaging stations; stage and contents for 15 lakes and reservoirs; water quality for 25 streams; and precipitation for 8 gaging stations. Also included are 15 crest-stage partial-record stations, 7 miscellaneous measurement sites, and 5 water-quality partial record stations. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in California.

  18. Water resources data, California, water year 2004, volume 1. southern Great Basin from Mexican border to Mono Lake Basin, and Pacific Slope basins from Tijuana River to Santa Maria River

    USGS Publications Warehouse

    Agajanian, J.; Caldwell, L.A.; Rockwell, G.L.; Pope, G.L.

    2005-01-01

    Water-resources data for the 2004 water year for California consist of records of stage, discharge, and water quality of streams, stage and contents in lakes and reservoirs, and water levels and water quality in wells. Volume 1 contains discharge records for 195 gaging stations and 10 crest-stage partial-record stations, stage and contents for 25 lakes and reservoirs, gage-height records for 2 stations, water quality for 47 streamflow-gaging stations and 7 partial-record stations, and precipitation data for 5 stations. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in California.

  19. Water Resources Data, California, Water Year 1990. Volume 1. Southern Great Basin from Mexican Border to Mono Lake Basin; and Pacific Slope Basins from Tijuana River to Santa Maria River

    USGS Publications Warehouse

    Bowers, J.C.; Jensen, R.M.; Hoffman, E.B.

    1991-01-01

    Water resources data for the 1990 water year for California consist of records of stage, discharge, and water quality of streams; stage and contents in lakes and reservoirs; and water levels and water quality in wells. Volume 1 contains discharge records for 157 streamflow-gaging stations, 16 crest-stage partial-record streamflow stations, and 2miscellaneous measurement stations; stage and contents records for 16 lakes and reservoirs; water-quality records for 19 streamflow-gaging stations, 2 partial-record stations; and precipitation records for 13 stations. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in California.

  20. Water Resources Data, California, Water Year 1997. Volume 1. Southern Great Basin from Mexican Border to Mono Lake Basin, and Pacific Slope Basins from Tijuana River to Santa Maria River

    USGS Publications Warehouse

    Hayes, P.D.; Agajanian, J.A.; Rockwell, G.L.

    1998-01-01

    Water-resources data for the 1997 water year for California consist of records of stage, discharge, and water quality of streams, stage and contents in lakes and reservoirs, and water levels and water quality in wells. Volume 1 contains discharge records for 151 gaging stations and 16 crest-stage partial-record stations, stage and contents for 21 lakes and reservoirs, gage height records for 1 station, water quality for 23 streamflow-gaging stations and 10 partialrecord stations, and precipitation data for 5 stations. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in Califomia.

  1. Water Resources Data -- California, Water Year 2003, Volume 1, Southern Great Basin from Mexican Border to Mono Lake Basin, and Pacific Slope Basins from Tijuana River to Santa Maria River

    USGS Publications Warehouse

    Pope, G.L.; Agajanian, J.; Caldwell, L.A.; Rockwell, G.L.

    2004-01-01

    Water-resources data for the 2003 water year for California consist of records of stage, discharge, and water quality of streams, stage and contents in lakes and reservoirs, and water levels and water quality in wells. Volume 1 contains discharge records for 193 gaging stations and 11 crest-stage partial-record stations, stage and contents for 22 lakes and reservoirs, gage-height records for 2 stations, water quality for 47 streamflow-gaging stations and 12 partial-record stations, and precipitation data for 1 station. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in California.

  2. Water Resources Data--California, Water Year 2001, Volume 1, Southern Great Basin from Mexican Border to Mono Lake Basin, and Pacific Slope Basins from Tijuana River to Santa Maria River

    USGS Publications Warehouse

    Agajanian, J.; Rockwell, G.L.; Anderson, S.W.; Pope, G.L.

    2002-01-01

    Water-resources data for the 2001 water year for California consist of records of stage, discharge, and water quality of streams, stage and contents in lakes and reservoirs, and water levels and water quality in wells. Volume 1 contains discharge records for 180 gaging stations and 13 crest-stage partial-record stations, stage and contents for 20 lakes and reservoirs, gage-height records for 2 stations, water quality for 37 streamflow-gaging stations and 2 partial-record stations, and precipitation data for 3 stations. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in California.

  3. Water Resources Data, California, Water Year 1993. Volume 1. Southern Great Basin from Mexican Border to Mono Lake Basin, and Pacific Slope Basins from Tijuana River to Santa Maria River

    USGS Publications Warehouse

    Mullen, J.R.; Hayes, P.D.; Agajanian, J.A.

    1994-01-01

    Water resources data for the 1993 water year for California consist of records of stage, discharge, and water quality of streams; stage and contents in lakes and reservoirs; and water levels and water quality in wells. Volume 1 contains (1) discharge records for 156 streamflow-gaging stations, 12 crest-stage partial-record streamflow stations, and 5 miscellaneous measurement stations; (2) stage and contents records for 26 lakes and reservoirs; (3) water-quality records for 17 streamflow-gaging stations and 6 partial-record stations; and (4) precipitation records for 10 stations . These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in California.

  4. Water Resources Data, California, Water Year 1992. Volume 1. Southern Great Basin from Mexican Border to Mono Lake Basin; and Pacific Slope Basins from Tijuana River to Santa Maria River

    USGS Publications Warehouse

    Hoffman, E.B.; Bowers, J.C.; Mullen, J.R.; Hayes, P.D.

    1993-01-01

    Water resources data for the 1992 water year for California consist of records of stage, discharge, and water quality of streams; stage and contents in lakes and reservoirs; and water levels and water quality in wells. Volume 1 contains (1) discharge records for 161 streamflow-gaging stations, 15 crest-stage partial-record streamflow stations, and 5 miscellaneous measurement stations; (2) stage and contents records for 26 lakes and reservoirs; (3) water-quality records for 23 streamflow-gaging stations and 3 partialrecord stations; and ( 4) precipitation records for 11 stations. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in California.

  5. Water Resources Data, California, Water Year 1998. Volume 1. Southern Great Basin from Mexican Border to Mono Lake Basin; and Pacific Slope Basins from Tijuana River to Santa Maria River

    USGS Publications Warehouse

    Agajanian, J.; Rockwell, G.L.; Hayes, P.D.; Anderson, S.W.

    1999-01-01

    Water-resources data for the 1998 water year for California consist of records of stage, discharge, and water quality of streams, stage and contents in lakes and reservoirs, and water levels and water quality in wells. Volume 1 contains discharge records for 157 gaging stations and 13 crest-stage partial-record stations, stage and contents for 21 lakes and reservoirs, gage-height records for 1 station, water quality for 22 streamflow-gaging stations and 14 partialrecord stations, and precipitation data for 3 stations. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in California.

  6. Water Resources Data--California, Water Year 2000, Volume 1, Southern Great Basin from Mexican Border to Mono Lake Basin, and Pacific Slope Basins from Tijuana River to Santa Maria River

    USGS Publications Warehouse

    Anderson, S.W.; Agajanian, J.; Rockwell, G.L.

    2001-01-01

    Water-resources data for the 2000 water year for California consist of records of stage, discharge, and water quality of streams, stage and contents in lakes and reservoirs, and water levels and water quality in wells. Volume 1 contains discharge records for 175 gaging stations and 13 crest-stage partial-record stations, stage and contents for 20 lakes and reservoirs, gage-height records for 2 stations, water quality for 27 streamflow-gaging stations and 3 partial-record stations, and precipitation data for 4 stations. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in California.

  7. Water Resources Data, California, Water Year 1995. Volume 1. Southern Great Basin from Mexican Border to Mono Lake Basin; and Pacific Slope Basins from Tijuana River to Santa Maria River

    USGS Publications Warehouse

    Agajanian, J.A.; Rockwell, G.L.; Hayes, P.D.

    1996-01-01

    Water resources data for the 1995 water year for California consist of records of stage, discharge, and water quality of streams; stage and contents in lakes and reservoirs; and water levels and water quality in wells. Volume 1 contains (1) discharge records for 141 streamflow-gaging stations, 6 crest-stage partial-record streamflow stations; (2) stage and contents records for 20 lakes and reservoirs; (3) water quality records for 21 streamflow-gaging stations and 3 partial-record stations; and (4) precipitation records for 1 station. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in California.

  8. Correlation analysis of tree growth, climate, and acid deposition in the Lake States. Forest Service research paper

    SciTech Connect

    Holdaway, M.R.

    1990-01-01

    The report describes research designed to detect subtle regional tree growth trends related to sulfate (SO{sub 4}) deposition in the Lake States. Correlation methods were used to analyze climatic and SO{sub 4} deposition. Effects of SO{sub 4} deposition are greater on climatically stressed trees, especially pine species on dry sites, than on unstressed trees. Jack pine growth shows the strongest correlation to both climate and acid deposition.

  9. Comparative study of cadmium and lead accumulations in Cambarus bartoni (Fab. ) (Decapoda, Crustacea) from an acidic and a neutral lake

    SciTech Connect

    Keenan, S.; Alikhan, M.A. )

    1991-07-01

    The purpose of the study reported in this paper was to compare concentrations of lead and cadmium in the sediment and water, as well as in the crayfish, Cambarus Bartoni (Fab.) (Decapoda - Crustacea) trapped from an acidic and a neutral lake in the Sudbury district of Northeastern Ontario. Hepatopancreatic, alimentary canal, tail muscles and exoskeletal concentrations in the crayfish are also examined to determine specific tissue sites for these accumulations.

  10. Interaction of the cesium cation with mono-, di-, and tricarboxylic acids in the gas phase. A Cs+ affinity scale for cesium carboxylates ion pairs.

    PubMed

    Mayeux, Charly; Tammiku-Taul, Jaana; Massi, Lionel; Lohu, Ene-Liis; Burk, Peeter; Maria, Pierre-Charles; Gal, Jean-François

    2009-10-01

    Humic substances (HS), including humic and fulvic acids, play a significant role in the fate of metals in soils. The interaction of metal cations with HS occurs predominantly through the ionized (anionic) acidic functions. In the context of the effect of HS on transport of radioactive cesium isotopes in soils, a study of the interaction between the cesium cation and model carboxylic acids was undertaken. Structure and energetics of the adducts formed between Cs+ and cesium carboxylate salts [Cs+RCOO-] were studied by the kinetic method and density functional theory (DFT). Clusters generated by electrospray ionization mass spectrometry from mixtures of a cesium salt (nitrate, iodide, trifluoroacetate) and carboxylic acids were quantitatively studied by CID. By combining the results of the kinetic method and the energetic data from DFT calculations, a scale of cesium cation affinity, CsCA, was built for 33 cesium carboxylates representing the first scale of cation affinity of molecular salts. The structural effects on the CsCA values are discussed.

  11. Brooktrout Lake case study: biotic recovery from acid deposition 20 years after the 1990 Clean Air Act Amendments.

    PubMed

    Sutherland, James W; Acker, Frank W; Bloomfield, Jay A; Boylen, Charles W; Charles, Donald F; Daniels, Robert A; Eichler, Lawrence W; Farrell, Jeremy L; Feranec, Robert S; Hare, Matthew P; Kanfoush, Sharon L; Preall, Richard J; Quinn, Scott O; Rowell, H Chandler; Schoch, William F; Shaw, William H; Siegfried, Clifford A; Sullivan, Timothy J; Winkler, David A; Nierzwicki-Bauer, Sandra A

    2015-03-03

    The Adirondack Mountain region is an extensive geographic area (26,305 km(2)) in upstate New York where acid deposition has negatively affected water resources for decades and caused the extirpation of local fish populations. The water quality decline and loss of an established brook trout (Salvelinus fontinalis [Mitchill]) population in Brooktrout Lake were reconstructed from historical information dating back to the late 1880s. Water quality and biotic recovery were documented in Brooktrout Lake in response to reductions of S deposition during the 1980s, 1990s, and 2000s and provided a unique scientific opportunity to re-introduce fish in 2005 and examine their critical role in the recovery of food webs affected by acid deposition. Using C and N isotope analysis of fish collagen and state hatchery feed as well as Bayesian assignment tests of microsatellite genotypes, we document in situ brook trout reproduction, which is the initial phase in the restoration of a preacidification food web structure in Brooktrout Lake. Combined with sulfur dioxide emissions reductions promulgated by the 1990 Clean Air Act Amendments, our results suggest that other acid-affected Adirondack waters could benefit from careful fish re-introduction protocols to initiate the ecosystem reconstruction of important components of food web dimensionality and functionality.

  12. Acidification in the Adirondacks: defining the biota in trophic levels of 30 chemically diverse acid-impacted lakes.

    PubMed

    Nierzwicki-Bauer, Sandra A; Boylen, Charles W; Eichler, Lawrence W; Harrison, James P; Sutherland, James W; Shaw, William; Daniels, Robert A; Charles, Donald F; Acker, Frank W; Sullivan, Timothy J; Momen, Bahram; Bukaveckas, Paul

    2010-08-01

    The Adirondack Mountains in New York State have a varied surficial geology and chemically diverse surface waters that are among the most impacted by acid deposition in the U.S. No single Adirondack investigation has been comprehensive in defining the effects of acidification on species diversity, from bacteria through fish, essential for understanding the full impact of acidification on biota. Baseline midsummer chemistry and community composition are presented for a group of chemically diverse Adirondack lakes. Species richness of all trophic levels except bacteria is significantly correlated with lake acid-base chemistry. The loss of taxa observed per unit pH was similar: bacterial genera (2.50), bacterial classes (1.43), phytoplankton (3.97), rotifers (3.56), crustaceans (1.75), macrophytes (3.96), and fish (3.72). Specific pH criteria were applied to the communities to define and identify acid-tolerant (pH<5.0), acid-resistant (pH 5.0-5.6), and acid-sensitive (pH>5.6) species which could serve as indicators. Acid-tolerant and acid-sensitive categories are at end-points along the pH scale, significantly different at P<0.05; the acid-resistant category is the range of pH between these end-points, where community changes continually occur as the ecosystem moves in one direction or another. The biota acid tolerance classification (batc) system described herein provides a clear distinction between the taxonomic groups identified in these subcategories and can be used to evaluate the impact of acid deposition on different trophic levels of biological communities.

  13. Novel Halomonas sp. B15 isolated from Larnaca Salt Lake in Cyprus that generates vanillin and vanillic acid from ferulic acid.

    PubMed

    Vyrides, Ioannis; Agathangelou, Maria; Dimitriou, Rodothea; Souroullas, Konstantinos; Salamex, Anastasia; Ioannou, Aristostodimos; Koutinas, Michalis

    2015-08-01

    Vanillin is a high value added product with many applications in the food, fragrance and pharmaceutical industries. A natural and low-cost method to produce vanillin is by microbial bioconversions through ferulic acid. Until now, limited microorganisms have been found capable of bioconverting ferulic acid to vanillin at high yield. This study aimed to screen halotolerant strains of bacteria from Larnaca Salt Lake which generate vanillin and vanillic acid from ferulic acid. From a total of 50 halotolenant/halophilic strains 8 grew in 1 g/L ferulic acid and only 1 Halomonas sp. B15 and 3 Halomonas elognata strains were capable of bioconverting ferulic acid to vanillic acid at 100 g NaCl/L. The highest vanillic acid (365 mg/L) at these conditions generated by Halomonas sp. B15 which corresponds to ferulic acid bioconversion yield of 36.5%. Using the resting cell technique with an initial ferulic acid concentration of 0.5 g/L at low salinity, the highest production of vanillin (245 mg/L) took place after 48 h, corresponding to a bioconversion yield of 49%. This is the first reported Halomonas sp. with high yield of vanillin production from ferulic acid at low salinity.

  14. Crystal structure of 4-(3-carb-oxy-pro-pan-amido)-2-hy-droxy-benzoic acid mono-hydrate.

    PubMed

    Tahir, Muhammad Nawaz; Ahmed, Muhammad Naeem; Butt, Arshad Farooq; Shad, Hazoor Ahmad

    2014-12-01

    In the title hydrate, C11H11NO6·H2O, the organic mol-ecule is approximately planar (r.m.s. deviation for the non-H atoms = 0.129 Å) and an intra-molecular O-H⋯O hydrogen bond closes an S(6) ring. In the crystal, the benzoic acid group participates in an O-H⋯O hydrogen bond to the water mol-ecule and accepts a similar bond from another water mol-ecule. The other -CO2H group forms a carb-oxy-lic acid inversion dimer, thereby forming an R 2 (2)(8) loop. These bonds, along with N-H⋯O and C-H⋯O inter-actions, generate a three-dimensional network.

  15. Microbial Diversity and Its Relationship to Physicochemical Characteristics of the Water in Two Extreme Acidic Pit Lakes from the Iberian Pyrite Belt (SW Spain)

    PubMed Central

    López-Pamo, Enrique; Gomariz, María; Amils, Ricardo; Aguilera, Ángeles

    2013-01-01

    The Iberian Pyrite Belt (IPB) hosts one of the world’s largest accumulations of acidic mine wastes and pit lakes. The mineralogical and textural characteristics of the IPB ores have favored the oxidation and dissolution of metallic sulfides, mainly pyrite, and the subsequent formation of acidic mining drainages. This work reports the physical properties, hydrogeochemical characteristics, and microbial diversity of two pit lakes located in the IPB. Both pit lakes are acidic and showed high concentrations of sulfate and dissolved metals. Concentrations of sulfate and heavy metals were higher in the Nuestra Señora del Carmen lake (NSC) by one order of magnitude than in the Concepción (CN) lake. The hydrochemical characteristics of NSC were typical of acid mine waters and can be compared with other acidic environments. When compared to other IPB acidic pit lakes, the superficial water of CN is more diluted than that of any of the others due, probably, to the strong influence of runoff water. Both pit lakes showed chemical and thermal stratification with well defined chemoclines. One particular characteristic of NSC is that it has developed a chemocline very close to the surface (2 m depth). Microbial community composition of the water column was analyzed by 16S and 18S rRNA gene cloning and sequencing. The microorganisms detected in NSC were characteristic of acid mine drainage (AMD), including iron oxidizing bacteria (Leptospirillum, Acidithiobacillus ferrooxidans) and facultative iron reducing bacteria and archaea (Acidithiobacillus ferrooxidans, Acidiphilium, Actinobacteria, Acidimicrobiales, Ferroplasma) detected in the bottom layer. Diversity in CN was higher than in NSC. Microorganisms known from AMD systems (Acidiphilium, Acidobacteria and Ferrovum) and microorganisms never reported from AMD systems were identified. Taking into consideration the hydrochemical characteristics of these pit lakes and the spatial distribution of the identified microorganisms, a

  16. Atmospheric oxalic acid and related secondary organic aerosols in Qinghai Lake, a continental background site in Tibet Plateau

    NASA Astrophysics Data System (ADS)

    Meng, Jingjing; Wang, Gehui; Li, Jianjun; Cheng, Chunlei; Cao, Junji

    2013-11-01

    Summertime PM2.5 aerosols collected from Qinghai Lake (3200 m a.s.l.), a remote continental site in the northeastern part of Tibetan Plateau, were analyzed for dicarboxylic acids (C2-C11), ketocarboxylic acids and α-dicarbonyals. Oxalic acid (C2) is the dominant dicarboxylic acid in the samples, followed by malonic, succinic and azelaic acids. Total dicarboxylic acids (231 ± 119 ng m-3), ketocarboxylic acids (8.4 ± 4.3 ng m-3), and α-dicarbonyls (2.7 ± 2.1 ng m-3) at the Tibetan background site are 2-5 times less than those detected in lowland areas such as 14 Chinese megacities. Compared to those in other urban and marine areas enhancements in relative abundances of C2/total diacids and diacids-C/WSOC of the PM2.5 samples suggest that organic aerosols in the region are more oxidized due to strong solar radiation. Molecular compositions and air mass trajectories demonstrate that the above secondary organic aerosols in the Qinghai Lake atmosphere are largely derived from long-range transport. Ratios of oxalic acid, glyoxal and methylglyoxal to levoglucosan in PM2.5 aerosols emitted from household burning of yak dung, a major energy source for Tibetan in the region, are 30-400 times lower than those in the ambient air, which further indicates that primary emission from biomass burning is a negligible source of atmospheric oxalic acid and α-dicarbonyls at this background site.

  17. Immune factors and fatty acid composition in human milk from river/lake, coastal and inland regions of China.

    PubMed

    Urwin, Heidi J; Zhang, Jian; Gao, Yixiong; Wang, Chunrong; Li, Lixiang; Song, Pengkun; Man, Qingqing; Meng, Liping; Frøyland, Livar; Miles, Elizabeth A; Calder, Philip C; Yaqoob, Parveen

    2013-06-01

    Breast milk fatty acid composition may be affected by the maternal diet during gestation and lactation. The influence of dietary and breastmilk fatty acids on breast milk immune factors is poorly defined. We determined the fatty acid composition and immune factor concentrations of breast milk from women residing in river/lake, coastal and inland regions of China, which differ in their consumption of lean fish and oily fish. Breast milk samples were collected on days 3–5 (colostrum), 14 and 28 post-partum (PP) and analysed for soluble CD14 (sCD14), transforming growth factor (TGF)-b1, TGF-b2, secretory IgA (sIgA) and fatty acids. The fatty acid composition of breast milk differed between the regions and with time PP. The concentrations of all four immune factors in breast milk decreased over time, with sCD14, sIgA and TGF-b1 being highest in the colostrum in the river and lake region. Breast milk DHA and arachidonic acid (AA) were positively associated, and g-linolenic acid and EPA negatively associated, with the concentrations of each of the four immune factors. In conclusion, breast milk fatty acids and immune factors differ between the regions in China characterised by different patterns of fish consumption and change during the course of lactation. A higher breast milk DHA and AA concentration is associated with higher concentrations of immune factors in breast milk, suggesting a role for these fatty acids in promoting gastrointestinal and immune maturation of the infant.

  18. Water resources data for California, water year 1979; Volume 1: Colorado River basin, Southern Great Basin from Mexican Border to Mono Lake basin, and Pacific slope basins from Tijuana River to Santa Maria River

    USGS Publications Warehouse

    ,

    1981-01-01

    Water-resources data for the 1979 water year for California consist of records of stage, discharge, and water quality of streams; stage, contents, and water quality of lakes and reservoirs; records of water levels in selected observation wells; and selected chemical analyses of ground water. Records for a few pertinent streamflow and water-quality stations in bordering States are also included. These data, a contribution to the National Water Data System, were collected by the Geological Survey and cooperating local, State, and Federal agencies in California.

  19. Water resources data for California, water year 1978; Volume 1: Colorado River basin, southern Great Basin from Mexican border to Mono Lake basin, and Pacific Slope basins from Tijuana River to Santa Maria River

    USGS Publications Warehouse

    ,

    1979-01-01

    Water-resources data for the 1978 water year for California consist of records of stage, discharge, and water quality of streams; stage, contents, and water quality of lakes and reservoirs; records of water levels in selected observation wells; and selected chemical analyses of ground water. Records for a few pertinent streamflow and water-quality stations in bordering States are also included. These data, a contribution to the National water Data System, were collected by the Geological Survey and cooperating local, State, and Federal agencies in California.

  20. Sources and haloacetic acid/trihalomethane formation potentials of aquatic humic substances in the Wakarusa River and Clinton Lake near Lawrence, Kansas

    USGS Publications Warehouse

    Pomes, M.L.; Larive, C.K.; Thurman, E.M.; Green, W.R.; Orem, W.H.; Rostad, C.E.; Coplen, T.B.; Cutak, B.J.; Dixon, A.M.

    2000-01-01

    Gram quantities of aquatic humic substances (AHS) were extracted from the Wakarusa River-Clinton Lake Reservoir system, near Lawrence, KS, to support nuclear magnetic resonance (NMR) experimental studies, report concentrations of dissolved organic carbon (DOC) and AHS, define sources of the AHS, and determine if the AHS yield sufficient quantities of haloacetic acids (HAA5) and trihalomethanes (THM4) that exceed U.S. Environmental Protection Agency (EPA) Maximum Contaminant Levels (MCL) in drinking water. AHS from the Wakarusa River and Clinton Lake originated from riparian forest vegetation, reflected respective effects of soil organic matter and aquatic algal/bacterial sources, and bore evidence of biological degradation and photodegradation. AHS from the Wakarusa River showed the effect of terrestrial sources, whereas Clinton Lake humicacid also reflected aquatic algal/bacterial sources. Greater amounts of carbon attributable to tannin-derived chemical structures may correspond with higher HAA5 and THM4 yields for Clinton Lake fulvic acid. Prior to appreciable leaf-fall from deciduous trees, the combined (humic and fulvic acid) THM4 formation potentials for the Wakarusa River approached the proposed EPA THM4 Stage I MCL of 80 ??g/L, and the combined THM4 formation potential for Clinton Lake slightly exceeded the proposed THM4 Stage II MCL of 40 ??g/L. Finally, AHS from Clinton Lake could account for most (>70%) of the THM4 concentrations in finished water from the Clinton Lake Water Treatment Plant based on September 23, 1996, THM4 results.Gram quantities of aquatic humic substances (AHS) were extracted from the Wakarusa River-Clinton Lake Reservoir system, near Lawrence, KS, to support nuclear magnetic resonance (NMR) experimental studies, report concentrations of dissolved organic carbon (DOC) and AHS, define sources of the AHS, and determine if the AHS yield sufficient quantities of haloacetic acids (HAA5) and trihalomethanes (THM4) that exceed U

  1. 13C NMR quantification of mono and diacylglycerols obtained through the solvent-free lipase-catalyzed esterification of saturated fatty acids.

    PubMed

    Fernandes, Jane Luiza Nogueira; de Souza, Rodrigo Octavio Mendonça Alves; de Vasconcellos Azeredo, Rodrigo Bagueira

    2012-06-01

    In the present investigation, we studied the enzymatic synthesis of monoacylglycerols (MAG) and diacylglycerols (DAG) via the esterification of saturated fatty acids (stearic, palmitic and an industrial residue containing 87% palmitic acid) and glycerol in a solvent-free system. Three immobilized lipases (Lipozyme RM IM, Lipozyme TL IM and Novozym 435) and different reaction conditions were evaluated. Under the optimal reaction conditions, esterifications catalyzed by Lipozyme RM IM resulted in a mixture of MAG and DAG at high conversion rates for all of the substrates. In addition, except for the reaction of industrial residue at atmospheric pressure, all of these products met the World Health Organization and European Union directives for acylglycerol mixtures for use in food applications. The products were quantified by (13)C NMR, with the aid of an external reference signal which was generated from a sealed coaxial tube filled with acetonitrile-d3. After calibrating the area of this signal using the classical external reference method, the same coaxial tube was used repeatedly to quantify the reaction products.

  2. Furan-based benzene mono- and dicarboxylic acid derivatives as multiple inhibitors of the bacterial Mur ligases (MurC-MurF): experimental and computational characterization

    NASA Astrophysics Data System (ADS)

    Perdih, Andrej; Hrast, Martina; Pureber, Kaja; Barreteau, Hélène; Grdadolnik, Simona Golič; Kocjan, Darko; Gobec, Stanislav; Solmajer, Tom; Wolber, Gerhard

    2015-06-01

    Bacterial resistance to the available antibiotic agents underlines an urgent need for the discovery of novel antibacterial agents. Members of the bacterial Mur ligase family MurC-MurF involved in the intracellular stages of the bacterial peptidoglycan biosynthesis have recently emerged as a collection of attractive targets for novel antibacterial drug design. In this study, we have first extended the knowledge of the class of furan-based benzene-1,3-dicarboxylic acid derivatives by first showing a multiple MurC-MurF ligase inhibition for representatives of the extended series of this class. Steady-state kinetics studies on the MurD enzyme were performed for compound 1, suggesting a competitive inhibition with respect to ATP. To the best of our knowledge, compound 1 represents the first ATP-competitive MurD inhibitor reported to date with concurrent multiple inhibition of all four Mur ligases (MurC-MurF). Subsequent molecular dynamic (MD) simulations coupled with interaction energy calculations were performed for two alternative in silico models of compound 1 in the UMA/ d-Glu- and ATP-binding sites of MurD, identifying binding in the ATP-binding site as energetically more favorable in comparison to the UMA/ d-Glu-binding site, which was in agreement with steady-state kinetic data. In the final stage, based on the obtained MD data novel furan-based benzene monocarboxylic acid derivatives 8- 11, exhibiting multiple Mur ligase (MurC-MurF) inhibition with predominantly superior ligase inhibition over the original series, were discovered and for compound 10 it was shown to possess promising antibacterial activity against S. aureus. These compounds represent novel leads that could by further optimization pave the way to novel antibacterial agents.

  3. Rate constants for 1,5- and 1,6-hydrogen atom transfer reactions of mono-, di-, and tri-aryl-substituted donors, models for hydrogen atom transfers in polyunsaturated fatty acid radicals.

    PubMed

    DeZutter, Christopher B; Horner, John H; Newcomb, Martin

    2008-03-06

    Rate constants for 1,5- and 1,6-hydrogen atom transfer reactions in models of polyunsaturated fatty acid radicals were measured via laser flash photolysis methods. Photolyses of PTOC (pyridine-2-thioneoxycarbonyl) ester derivatives of carboxylic acids gave primary alkyl radicals that reacted by 1,5-hydrogen transfer from mono-, di-, and tri-aryl-substituted positions or 1,6-hydrogen transfer from di- and tri-aryl-substituted positions to give UV-detectable products. Rate constants for reactions in acetonitrile at room temperature ranged from 1 x 10(4) to 4 x 10(6) s(-1). The activation energies for a matched pair of 1,5- and 1,6-hydrogen atom transfers giving tri-aryl-substituted radicals were approximately equal, as were the primary kinetic isotope effects, but the 1,5-hydrogen atom transfer reaction was 1 order of magnitude faster at room temperature than the 1,6-hydrogen atom transfer reaction due to a less favorable entropy of activation for the 1,6-transfer reaction. Solvent effects on the rate constants for the 1,5-hydrogen atom transfer reaction of the 2-[2-(diphenylmethyl)phenyl]ethyl radical at ambient temperature were as large as a factor of 2 with the reaction increasing in rate in lower polarity solvents. Hybrid density functional theory computations for the 1,5- and 1,6-hydrogen atom transfers of the tri-aryl-substituted donors were in qualitative agreement with the experimental results.

  4. A combined CaO/electrochemical treatment of the acid mine drainage from the "Robule" Lake.

    PubMed

    Orescanin, Visnja; Kollar, Robert

    2012-01-01

    The purpose of this work was development and application of the purification system suitable for the treatment of the acid mine drainage (AMD) accumulated in the "Robule" Lake, which represents the part of the Bor copper mining and smelting complex, Serbia. The study was undertaken in order to minimize adverse effect on the environment caused by the discharge of untreated AMD, which was characterized with low pH value (2.63) and high concentration of heavy metals (up to 610 mg/L) and sulfates (up to 12,000 mg/L). The treatment of the effluent included pretreatment/pH adjustment with CaO followed by electrocoagulation using iron and aluminum electrode sets. Following the final treatment, the decrease in the concentration of heavy metals ranged from 40 up to 61000 times depending on the metal and its initial concentration. The parameters, color and turbidity were removed completely in the pretreatment step, while the removal efficiencies for other considered parameters were as follows: EC = 55.48%, SO(4) (2-) = 70.83%, Hg = 98.36%, Pb = 97.50%, V = 98.43%, Cr = 99.86%, Mn = 97.96%, Fe = 100.00%, Co = 99.96%, Ni = 99.78%, Cu = 99.99% and Zn = 99.94%. Because the concentrations of heavy metals in the electrochemically treated AMD (ranging from 0.001 to 0.336 mg/L) are very low, the negative impact of this effluent on the aquatic life and humans is not expected. The sludge generated during the treatment of AMD is suitable for reuse for at least two purposes (pretreatment of AMD and covering of the flotation waste heap). From the presented results, it could be concluded that electrochemical treatment is a suitable approach for the treatment of AMD.

  5. Organic matter in sediment layers of an acidic mining lake as assessed by lipid analysis. Part II: Neutral lipids.

    PubMed

    Poerschmann, Juergen; Koschorreck, Matthias; Górecki, Tadeusz

    2017-02-01

    Natural neutralization of acidic mining lakes is often limited by organic matter. The knowledge of the sources and degradability of organic matter is crucial for understanding alkalinity generation in these lakes. Sediments collected at different depths (surface sediment layer from 0 to 1 cm and deep sediment layer from 4 to 5cm) from an acidic mining lake were studied in order to characterize sedimentary organic matter based on neutral signature markers. Samples were exhaustively extracted, subjected to pre-chromatographic derivatizations and analyzed by GC/MS. Herein, molecular distributions of diagnostic alkanes/alkenes, terpenes/terpenoids, polycyclic aromatic hydrocarbons, aliphatic alcohols and ketones, sterols, and hopanes/hopanoids were addressed. Characterization of the contribution of natural vs. anthropogenic sources to the sedimentary organic matter in these extreme environments was then possible based on these distributions. With the exception of polycyclic aromatic hydrocarbons, combined concentrations across all marker classes proved higher in the surface sediment layer as compared to those in the deep sediment layer. Alkane and aliphatic alcohol distributions pointed to predominantly allochthonous over autochthonous contribution to sedimentary organic matter. Sterol patterns were dominated by phytosterols of terrestrial plants including stigmasterol and β-sitosterol. Hopanoid markers with the ββ-biohopanoid "biological" configuration were more abundant in the surface sediment layer, which pointed to higher bacterial activity. The pattern of polycyclic aromatic hydrocarbons pointed to prevailing anthropogenic input. Pyrolytic makers were likely to due to atmospheric deposition from a nearby former coal combustion facility. The combined analysis of the array of biomarkers provided new insights into the sources and transformations of organic matter in lake sediments.

  6. Quantification of 15 bile acids in lake charr feces by ultra-high performance liquid chromatography-tandem mass spectrometry.

    PubMed

    Li, Ke; Buchinger, Tyler J; Bussy, Ugo; Fissette, Skye D; Johnson, Nicholas S; Li, Weiming

    2015-09-15

    Many fishes are hypothesized to use bile acids (BAs) as chemical cues, yet quantification of BAs in biological samples and the required methods remain limited. Here, we present an UHPLC-MS/MS method for simultaneous, sensitive, and rapid quantification of 15 BAs, including free, taurine, and glycine conjugated BAs, and application of the method to fecal samples from lake charr (Salvelinus namaycush). The analytes were separated on a C18 column with acetonitrile-water (containing 7.5mM ammonium acetate and 0.1% formic acid) as mobile phase at a flow rate of 0.25mL/min for 12min. BAs were monitored with a negative electrospray triple quadrupole mass spectrometer (Xevo TQ-S™). Calibration curves of 15 BAs were linear over the concentration range of 1.00-5,000ng/mL. Validation revealed that the method was specific, accurate, and precise. The method was applied to quantitative analysis of feces extract of fry lake charr and the food they were eating. The concentrations of analytes CA, TCDCA, TCA, and CDCA were 242.3, 81.2, 60.7, and 36.2ng/mg, respectively. However, other taurine conjugated BAs, TUDCA, TDCA, and THDCA, were not detected in feces of lake charr. Interestingly, TCA and TCDCA were detected at high concentrations in food pellets, at 71.9 and 38.2ng/mg, respectively. Application of the method to feces samples from lake charr supported a role of BAs as chemical cues, and will enhance further investigation of BAs as chemical cues in other fish species.

  7. Quantification of 15 bile acids in lake charr feces by ultra-high performance liquid chromatography–tandem mass spectrometry

    USGS Publications Warehouse

    Li, Ke; Buchinger, Tyler J.; Bussy, Ugo; Fissette, Skye D; Johnson, Nicholas; Li, Weiming

    2015-01-01

    Many fishes are hypothesized to use bile acids (BAs) as chemical cues, yet quantification of BAs in biological samples and the required methods remain limited. Here, we present an UHPLC–MS/MS method for simultaneous, sensitive, and rapid quantification of 15 BAs, including free, taurine, and glycine conjugated BAs, and application of the method to fecal samples from lake charr (Salvelinus namaycush). The analytes were separated on a C18 column with acetonitrile–water (containing 7.5 mM ammonium acetate and 0.1% formic acid) as mobile phase at a flow rate of 0.25 mL/min for 12 min. BAs were monitored with a negative electrospray triple quadrupole mass spectrometer (Xevo TQ-S™). Calibration curves of 15 BAs were linear over the concentration range of 1.00–5,000 ng/mL. Validation revealed that the method was specific, accurate, and precise. The method was applied to quantitative analysis of feces extract of fry lake charr and the food they were eating. The concentrations of analytes CA, TCDCA, TCA, and CDCA were 242.3, 81.2, 60.7, and 36.2 ng/mg, respectively. However, other taurine conjugated BAs, TUDCA, TDCA, and THDCA, were not detected in feces of lake charr. Interestingly, TCA and TCDCA were detected at high concentrations in food pellets, at 71.9 and 38.2 ng/mg, respectively. Application of the method to feces samples from lake charr supported a role of BAs as chemical cues, and will enhance further investigation of BAs as chemical cues in other fish species.

  8. Benthic plant communities in acidic Lake Colden, New York: Sphagnum and the algal mat

    SciTech Connect

    Hendrey, G R; Vertucci, J A

    1980-03-01

    Lake Colden, in the central Adirondack Mountains of New York State is botanically similar to acidified lakes in Sweden. Acidification of some Swedish lakes has been associated with an expansion of Sphagnum, primarily in shallow, sheltered littoral areas but also to depths of 18m. During a brief botanical survey on 24-25 July 1979, we observed a dense meadow of Sphagnum pylaesii around much of the shoreline of Lake Colden. Plant community composition was determined by a visual estimate of cover along a single typical transect and through underwater photography on 28-29 August 1979. Water samples were collected and returned to our laboratory for analyses several days later. Sample pH was determined by potentiometry and alkalinity by multiple end point titrations. Biomass samples were also taken of the Sphagnum mat community and dry weight was determined. Chemical content of plant tissue was analyzed.

  9. Water resources data for California, water year 1976; Volume 1: Colorado River basin, southern Great Basin from Mexican border to Mono Lake basin, and Pacific Slope basins from Tijuana River to Santa Maria River

    USGS Publications Warehouse

    ,

    1977-01-01

    Water-resources data for the 1976 water year for California consist of records of stage, discharge, and water quality of streams; stage, contents, and water quality of lakes and reservoirs; records of water levels in selected observation wells; and selected chemical analyses of ground water. Records for a few pertinent streamflow and water-quality stations in bordering States are also included. The records were collected and computed by the Water Resources Division of the U.S. Geological Survey under the direction of Lee R. Peterson, district chief; Winchell Smith, assistant district chief for hydrologic data; and Leonard N. Jorgensen, chief of the basic-data section. These data, a contribution to the National Water Data System, were collected by the Geological Survey and cooperating local, State, and Federal agencies in California.

  10. Water resources data for California, water year 1977; Volume 1: Colorado River Basin, Southern Great Basin from Mexican Border to Mono Lake Basin, and Pacific Slope Basins from Tijuana River to Santa Maria River

    USGS Publications Warehouse

    ,

    1978-01-01

    Water-resources data for the 1977 water year for California consist of records of stage, discharge, and water quality of streams; stage, contents, and water quality of lakes and reservoirs; records of water levels in selected observation wells; and selected chemical analyses of ground water. Records for a few pertinent streamflow and water-quality stations in bordering States are also included. The records were collected and computed by the Water Resources Division of the U.S. Geological Survey under the direction of Winchell Smith, Assistant District Chief for Hydrologic Data and Leonard N. Jorgensen, Chief of the Basic-Data Section. These data, a contribution to the National Water Data System, were collected by the Geological Survey and cooperating local, State, and Federal agencies in California.

  11. Three-Dimensional Analysis of dike/fault interaction at Mono Basin (California) using the Finite Element Method

    NASA Astrophysics Data System (ADS)

    La Marra, D.; Battaglia, M.

    2013-12-01

    Mono Basin is a north-trending graben that extends from the northern edge of Long Valley caldera towards the Bodie Hills and is bounded by the Cowtrack Mountains on the east and the Sierra Nevada on the west. The Mono-Inyo Craters volcanic chain forms a north-trending zone of volcanic vents extending from the west moat of the Long Valley caldera to Mono Lake. The Hartley Springs fault transects the southern Mono Craters-Inyo Domes area between the western part of the Long Valley caldera and June Lake. Stratigraphic data suggest that a series of strong earthquakes occurred during the North Mono-Inyo eruption sequence of ~1350 A.D. The spatial and temporal proximity between Hartley Springs Fault motion and the North Mono-Inyo eruption sequence suggests a possible relation between seismic events and eruptions. We investigate the interactions between slip along the Hartley Springs fault and dike intrusion beneath the Mono-Inyo craters using a three-dimensional finite element model of the Mono Basin. We employ a realistic representation of the Basin that includes topography, vertical and lateral heterogeneities of the crust, contact relations between fault planes, and a physical model of the pressure required to propagate the dike. We estimate (a) the distribution of Coulomb stress changes to study the influence of dike intrusion on Hartley Springs fault, and (b) the local stress and volumetric dilatation changes to understand how fault slip may influence the propagation of a dike towards the surface.

  12. Temperature Trends in Montane Lakes

    NASA Astrophysics Data System (ADS)

    Melack, J. M.; Sadro, S.; Jellison, R.

    2014-12-01

    Long-term temperature trends in lakes integrate hydrological and meteorological factors. We examine temperature trends in a small montane lake with prolonged ice-cover and large seasonal snowfall and in a large saline lake. Emerald Lake, located in the Sierra Nevada (California), is representative of high-elevation lakes throughout the region. No significant trend in outflow temperature was apparent from 1991to 2012. Snowfall in the watershed accounted for 93% of the variability in average summer lake temperatures. Mono Lake (California) lies in a closed, montane basin and is hypersaline and monomictic or meromictic. Temperature profiles have been collected from 1982 to 2010. In the upper water column, the July-August-September water temperatures increased 0.8-1.0°C over the 29 years. This rate of warming is less than published estimates based on satellite-derived skin temperatures and will discussed in the context of general limnological interpretation of temperature trends.

  13. 238U-230Th crystallization ages for the oldest domes of the Mono Craters, eastern California

    NASA Astrophysics Data System (ADS)

    Marcaida, M.; Vazquez, J. A.

    2014-12-01

    The Mono Craters volcanic chain is one of the youngest areas of rhyolitic volcanism in the Mono Lake-Long Valley region of eastern California. Located just south of Mono Lake, the Mono Craters comprise at least 28 individual domes and flows (numbered 3-30, north to south); however, the timing and frequency of eruptions remain poorly resolved. The earliest signs of volcanic activity are preserved as numerous tephra layers (Ashes 1-19, top to bottom) in the late Pleistocene Wilson Creek formation of ancestral Mono Lake, which indicate that rhyolitic volcanism from Mono Craters began by at least ca. 62 ka [1]. Although the current chronology indicates that most of the Mono Craters are younger than ca. 20 ka [2-4], similar compositions of titanomagnetite from both pumice and lava potentially correlate several Wilson Creek tephras to porphyritic biotite-bearing domes 11, 24, and 19 of the Mono Craters [5], suggesting that multiple domes in the Mono Craters chain reflect volcanism older than ca. 20 ka. Ash 3 is correlated to dome 11 based on similar ca. 20 ka ages and titanomagnetite compositions [6]. More recently, we performed ion microprobe 238U-230Th dating of unpolished rims of allanite and zircon from domes 24 and 19, yielding isochron ages of ca. 38 ka and ca. 42 ka, respectively. The age of dome 24 is consistent with the ca. 38 ka age of its potential correlative tephra layers [1, 5], indicating that dome 24 is likely the extrusive equivalent of Ashes 9-10. Dome 19 has titanomagnetite crystals with similar bimodal chemistry to titanomagnetites from Ash 15 [5]. The age of dome 19 is indistinguishable from the 238U-230Th age of Ash 15 [1], which erupted during a prominent geomagnetic excursion, originally designated as the "Mono Lake" excursion. Combining geochronological and titanomagnetite compositional data confirms that Ash 15 and its extrusive equivalent, dome 19, erupted during the Laschamp excursion. [1] Vazquez, J.A. and Lidzbarski, M.I. (2012) EPSL 357

  14. The bioaccessibility of eicosapentaenoic acid was higher from phospholipid food products than from mono- and triacylglycerol food products in a dynamic gastrointestinal model

    PubMed Central

    Domoto, Nobuhiko; Koenen, Marjorie E; Havenaar, Robert; Mikajiri, Akihiro; Chu, Boon-Seang

    2013-01-01

    The bioaccessibility of eicosapentaenoic acid (EPA) in the forms of monoacylglycerol (EPA-MAG), triacylglycerol (EPA-TAG), and phospholipid (EPA-PL) during gastrointestinal passage was compared in this study using a dynamic gastrointestinal model (TIM system). The TIM system simulated the average upper gastrointestinal tract conditions of healthy human adults after intake of a meal (fed state conditions). In this study, the three EPA-rich oils were separately homogenized with full fat milk to obtain oil-in-water emulsions. Plain yogurt was added into the mixture at an emulsion/yogurt ratio of 4:1 (w/w) as the food matrix of the test products. The results show that the test meals containing EPA-PL left the stomach compartment most efficiently in comparison with the gastric emptying of EPA-MAG and EPA-TAG. The PLs also showed a significantly (P < 0.05) higher bioaccessibility of EPA (75–80%) in comparison with MAG (30%) and TAG (38%). The better gastric emptying of EPA-PL was likely related to the more stable emulsion of EPA-PL in the test meal. EPA-PL was delivered within the meal matrix into the duodenum instead of floating on the top of the test meal matrix. EPA-MAG had the highest amount of EPA that did not leave the stomach (68% of the test meal). The results from this work indicate that EPA-PL is a more effective form of EPA for a higher lipid bioaccessibility than MAG and TAG under the test conditions. PMID:24804049

  15. Labile aluminium chemistry downstream a limestone treated lake and an acid tributary: effects of warm winters and extreme rainstorms.

    PubMed

    Andersen, Dag O

    2006-08-01

    The outlet from the limestone treated Lake Terjevann consisted mainly of well-mixed lake water (mean pH 6.1) during the ice-free seasons including the unusually warm winters of 1992 and 1993. However, during the ice-covered period acidic water (mean pH 4.8, mean inorganic aluminium (Al(i)) about 160 microg/l) from the catchment draining under the lake ice dominated. A downstream tributary was generally acid and rich in aluminium (mean pH 4.6, Al(i) about 230 microg/l). After an extreme rainstorm loaded with sea-salts cation exchange in the soil resulted in more than a doubling of the Al(i) concentration (reaching about 500 microg/l). It took 3-4 months until the Al(i) concentration returned to pre-event levels. During the ice-covered period, the acidic outlet and tributary waters resulted in acidic conditions below the confluence (pH<4.8, Al(i) about 150 microg/l) while during the ice-free periods the more neutral outlet water resulted in higher pH and lower Al(i) concentrations (pH>5.2, Al(i) about 95 microg/l). However, during the latter climatic conditions the water was most probably more harmful to fish due to hydrolysing and polymerizing aluminium. After the sea-salt event, the increased Al(i) concentration in the tributary made the zone below the confluence potentially more toxic (pH approximately 5, Al(i) approximately 250 microg/l). Expected global warming resulting in winter mean temperatures above 0 degrees C may eliminate the seasonal acidification of the outlet from limestone-treated lakes creating permanent toxic mixing zones in the confluence below acidic aluminium-rich tributaries. Besides, more frequent rainstorms as a consequence of global warming may increase the frequency of sea-salt events and the Al(i) concentrations in the mixing zones.

  16. Capillary Electrophoresis of Mono- and Oligosaccharides.

    PubMed

    Toppazzini, Mila; Coslovi, Anna; Rossi, Marco; Flamigni, Anna; Baiutti, Edi; Campa, Cristiana

    2016-01-01

    This chapter reports an overview of the recent advances in the analysis of mono- and oligosaccharides by capillary electrophoresis (CE); furthermore, relevant reviews and research articles recently published in the field are tabulated. Additionally, pretreatments and procedures applied to uncharged and acidic carbohydrates (i.e., monosaccharides and lower oligosaccharides carrying carboxylate, sulfate, or phosphate groups) are described.Representative examples of such procedures are reported in detail, upon describing robust methodologies for the study of (1) neutral oligosaccharides derivatized by reductive amination and by formation of glycosylamines; (2) sialic acid derivatized with 2-aminoacridone, released from human serum immunoglobulin G; (3) anomeric couples of neutral glycosides separated using borate-based buffers; (4) unsaturated, underivatized oligosaccharides from lyase-treated alginate.

  17. Lake acidification

    SciTech Connect

    Dobson, J.E.; Peplies, R.W.; Rush, R.M.

    1987-06-01

    This paper examined a National Research Council (NRC) report called Acid Deposition: Long-Term Trends. The report has been the final word on acid deposition as the cause of acidification of lakes. The authors considered it important that the tentative nature of this report be kept in perspective so that the work of the NRC would promote rather than inhibit scientific inquiry on the lake acidification issue. In this spirit, this report proposed that degradation of storm damaged trees could increase the acidity of the forest humus and as a result the ground water which would fed local streams and lakes. They proposed that extensive forest blowdown could be a factor in acidification of surface waters.

  18. Quaternary Eruptions of the Mono-Inyo Craters, California

    NASA Astrophysics Data System (ADS)

    Bursik, M. I.; Pouget, S.; Mangan, M.; Marcaida, M.; Vazquez, J. A.

    2013-12-01

    The eruptive products of the Mono-Inyo Craters volcanic chain include the tephra and associated volcanic rocks of Black Point, islands of Mono Lake, Mono Craters, Inyo Craters, late eruptions of Mammoth Mountain and Red Cones. Most of the eruptions were explosive, and generated numerous pyroclastic flows, surges and falls as well as the prominent domes and lava flows that now cover vents. The eruptions range in age from several hundred years to at least 60,000 yr BP. The Mono-Inyo tephras are dispersed throughout the Sierra Nevada and Basin and Range, providing key time-stratigraphic marker layers. Recent work has not only resulted in high-precision radiometric dating of many of the tephras, but also detailed geochemical data that for the first time provides fingerprinting sufficiently precise to discriminate among the tephras. Lithostratigraphy of many of the layers is herein described for the first time, based on careful sampling and description in the field, and laboratory grain size, grain shape and componentry analyses of the late Pleistocene tephras of the Wilson Creek Formation. Most of the Wilson Creek volcanic layers are fall deposits accumulated within paleolake Russell, which were generated by eruptions of variable intensity and influenced by paleowinds of different orientation. Prevailing winds were generally to the North and East, but often the Pleistocene layers less than 25 ka were dispersed to the West. Many of the fall layers show evidence of wave reworking, generally near the top, although in some cases it is pervasive. Only near the vent do some layers of apparent debris flow origin occur. Maximum pumice sizes range up to nearly 3 cm, and lithics range up to 1 cm in the rhyolitic fall beds, while thicknesses range up to c. 30 cm. These data are consistent with relatively low volume, subplinian style eruptive behavior for most of the life of the Mono-Inyo Craters.

  19. Effects of different cooking methods on fatty acid profiles in four freshwater fishes from the Laurentian Great Lakes region.

    PubMed

    Neff, Margaret R; Bhavsar, Satyendra P; Braekevelt, Eric; Arts, Michael T

    2014-12-01

    Fish is often promoted as a healthy part of the human diet due its high content of long chain n-3 polyunsaturated fatty acids (LC-PUFA). Previous studies have shown that cooked fish can have different fatty acid profiles than raw fillets, depending on the cooking method and fish species. In this study, the fatty acid content of broiled, baked or fried skinless, boneless fillets of four fish species from the tributaries of the Great Lakes, or connecting rivers, was compared to fatty acid profiles in raw sections from the same fillet. Cooking treatments had little effect on n-3 fatty acid content; however, fried treatments generally had higher n-6 and MUFA content, which is likely a result of the cooking oil used (canola). Broiling or baking is generally the most healthy option presented in this study, as these methods result in lower levels of less-favourable fatty acids; however, the choice of cooking oil may also influence the overall fatty acid content in cooked fish.

  20. Determining D/L Ratios of Amino Acids Found in Ice Above Lake Vostok Using ESI/CIT Mass Spectroscopy

    NASA Technical Reports Server (NTRS)

    Tsapin, A.; Kanik, I.; Beegle, L. W.; Wu, L.; Cooks, R. G.

    2003-01-01

    Astrobiology is an area where longevity of (micro) organisms is of great interest. Cryospheres are common phenomena in the solar system, particularly on satellites, comets and asteroids, as well as at least some of the planets. Recent data from the Mars Global Surveyor mission suggest the possibility of permafrost or perhaps even liquid water under the Martian surface [2]. These environments may be the areas in which the probability of finding life is the highest. This issue is of concern due to the probable evolution of planetary environments such as that of Mars from more hospitable to less hospitable conditions over the history of the solar system. In addition, evaluation of the possible transfer of living organisms between planets via impact ejecta [3] is dependent on knowledge of the maximum time periods over which microorganisms can remain dormant and subsequently revive and reproduce.Amino acid racemization dating, or aminostratigraphy, has been used for many years to date biological systems, and has been examined as a possible biosignature detection technique for Mars. We have suggested using amino acid racemization as one of the most indicative biosignatures [4]. Only life systems produce preferential synthesis of L-amino acids versus D-amino acids. Almost all amino acids in terrestrial organisms can be found only in the L-enantiomeric form.We studied the level of amino acid racemization, specifically of aspartic acid, in permafrost samples from eastern Siberia. Also we analyzed samples of ice from borehole drilled to lake Vostok, Antarctica.

  1. Processes at the sediment water interface after addition of organic matter and lime to an acid mine pit lake mesocosm

    SciTech Connect

    Matthias Koschorreck; Elke Bozau; Rene Froemmichen; Walter Geller; Peter Herzsprung; Katrin Wendt-Potthoff

    2007-03-01

    A strategy to neutralize acidic pit lakes was tested in a field mesocosm of 4500 m{sup 3} volume in the Acidic Pit Mine Lake 111 in the Koyne-Plessa lignite mining district of Lusatia, Germany. Carbokalk, a byproduct from sugar production, and wheat straw was applied near to the sediment surface to stimulate in lake microbial alkalinity generation by sulfate and iron reduction. The biogeochemical processes at the sediment-water interface were studied over 3 years by geochemical monitoring and an in situ microprofiler. Substrate addition generated a reactive zone at the sediment surface where sulfate and iron reduction proceeded. Gross sulfate reduction reached values up to 10 mmol m{sup -2} d{sup -1}. The neutralization rates between 27 and 0 meq m{sup -2} d{sup -1} were considerably lower than in previous laboratory experiments. The precipitation of ferric iron minerals resulted in a growing acidic sediment layer on top of the neutral sediment. In this layer sulfate reduction was observed but iron sulfides could not precipitate. In the anoxic sediment H{sub 2}S was oxidized by ferric iron minerals. H{sub 2}S partly diffused to the water column where it was oxidized. As a result the net formation of iron sulfides decreased after 1 year although gross sulfate reduction rates continued to be high. The rate of iron reduction exceeded the sulfate reduction rate, which resulted in high fluxes of ferrous iron out of the sediment. 46 refs., 6 figs., 1 tab.

  2. Syntrophic associations from hypersaline soda lakes converting organic acids and alcohols to methane at extremely haloalkaline conditions.

    PubMed

    Sorokin, Dimitry Y; Abbas, Ben; Geleijnse, Mitchell; Kolganova, Tatjana V; Kleerebezem, Robbert; van Loosdrecht, Mark C M

    2016-09-01

    Until now anaerobic oxidation of VFA at high salt-pH has been demonstrated only at sulfate-reducing conditions. Here, we present results of a microbiological investigation of anaerobic conversion of organic acids and alcohols at methanogenic conditions by syntrophic associations enriched from hypersaline soda lakes in Central Asia. Sediment incubation experiments showed active, albeit very slow, methane formation from acetate, propionate, butyrate and C2 C4 alcohols at pH 10 and various levels of salinity. Enrichments of syntrophic associations using hydrogenotrophic members of the genus Methanocalculus from soda lakes as partners resulted in several highly enriched cultures converting acetate, propionate, butyrate, benzoate and EtOH to methane. Most syntrophs belonged to Firmicutes, while the propionate-oxidizer formed a novel lineage within the family Syntrophobacteraceae in the Deltaproteobacteria. The acetate-oxidizing syntroph was identified as 'Ca. Syntrophonatronum acetioxidans' previously found to oxidize acetate at sulfate-reducing conditions up to salt-saturating concentrations. Butyrate and a benzoate-degrading syntrophs represent novel genus-level lineages in Syntrophomonadales which are proposed as Candidatus taxons 'Syntrophobaca', 'Syntrophocurvum' and 'Syntropholuna'. Overall, despite very slow growth, the results indicated the presence of a functionally competent syntrophic community in hypersaline soda lakes, capable of efficient oxidation of fermentation products to methane at extremely haloalkaline conditions.

  3. Diet of yellow-billed loons (Gavia adamsii) in Arctic lakes during the nesting season inferred from fatty acid analysis

    USGS Publications Warehouse

    Haynes, T B; Schmutz, Joel A.; Bromaghin, Jeffrey; Iverson, S J; Padula, V. M.; Rosenberger, A E

    2015-01-01

    Understanding the dietary habits of yellow-billed loons (Gavia adamsii) can give important insights into their ecology, however, studying the diet of loons is difficult when direct observation or specimen collection is impractical. We investigate the diet of yellow-billed loons nesting on the Arctic Coastal Plain of Alaska using quantitative fatty acid signature analysis. Tissue analysis from 26 yellow-billed loons and eleven prey groups (nine fish species and two invertebrate groups) from Arctic lakes suggests that yellow-billed loons are eating high proportions of Alaska blackfish (Dallia pectoralis), broad whitefish (Coregonus nasus) and three-spined stickleback (Gasterosteus aculeatus) during late spring and early summer. The prominence of blackfish in diets highlights the widespread availability of blackfish during the early stages of loon nesting, soon after spring thaw. The high proportions of broad whitefish and three-spined stickleback may reflect a residual signal from the coastal staging period prior to establishing nesting territories on lakes, when loons are more likely to encounter these species. Our analyses were sensitive to the choice of calibration coefficient based on data from three different species, indicating the need for development of loon-specific coefficients for future study and confirmation of our results. Regardless, fish that are coastally distributed and that successfully overwinter in lakes are likely key food items for yellow-billed loons early in the nesting season.

  4. 21 CFR 582.4521 - Monosodium phosphate derivatives of mono- and diglycerides of edible fats or oils, or edible fat...

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... diglycerides of edible fats or oils, or edible fat-forming fatty acids. 582.4521 Section 582.4521 Food and... Monosodium phosphate derivatives of mono- and diglycerides of edible fats or oils, or edible fat-forming fatty acids. (a) Product. Monosodium phosphate derivatives of mono- and diglycerides of edible fats...

  5. 21 CFR 582.4521 - Monosodium phosphate derivatives of mono- and diglycerides of edible fats or oils, or edible fat...

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... diglycerides of edible fats or oils, or edible fat-forming fatty acids. 582.4521 Section 582.4521 Food and... Monosodium phosphate derivatives of mono- and diglycerides of edible fats or oils, or edible fat-forming fatty acids. (a) Product. Monosodium phosphate derivatives of mono- and diglycerides of edible fats...

  6. 21 CFR 582.4521 - Monosodium phosphate derivatives of mono- and diglycerides of edible fats or oils, or edible fat...

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... diglycerides of edible fats or oils, or edible fat-forming fatty acids. 582.4521 Section 582.4521 Food and... Monosodium phosphate derivatives of mono- and diglycerides of edible fats or oils, or edible fat-forming fatty acids. (a) Product. Monosodium phosphate derivatives of mono- and diglycerides of edible fats...

  7. 21 CFR 582.4521 - Monosodium phosphate derivatives of mono- and diglycerides of edible fats or oils, or edible fat...

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... diglycerides of edible fats or oils, or edible fat-forming fatty acids. 582.4521 Section 582.4521 Food and... Monosodium phosphate derivatives of mono- and diglycerides of edible fats or oils, or edible fat-forming fatty acids. (a) Product. Monosodium phosphate derivatives of mono- and diglycerides of edible fats...

  8. Acid rain recovery may help to mitigate the impacts of climate change on thermally sensitive fish in lakes across eastern North America.

    PubMed

    Warren, Dana R; Kraft, Clifford E; Josephson, Daniel C; Driscoll, Charles T

    2016-12-15

    From the 1970s to 1990s, more stringent air quality regulations were implemented across North America and Europe to reduce chemical emissions that contribute to acid rain. Surface water pH slowly increased during the following decades, but biological recovery lagged behind chemical recovery. Fortunately, this situation is changing. In the past few years, northeastern US fish populations have begun to recover in lakes that were historically incapable of sustaining wild fish due to acidic conditions. As lake ecosystems across the eastern United States recover from acid deposition, the stress to the most susceptible populations of native coldwater fish appears to be shifting from acidification effects to thermal impacts associated with changing climate. Extreme summer temperature events - which are expected to occur with increasing frequency in the coming century - can stress and ultimately kill native coldwater fish in lakes where thermal stratification is absent or highly limited. Based on data from northeastern North America, we argue that recovery from acid deposition has the potential to improve the resilience of coldwater fish populations in some lakes to impacts of climate change. This will occur as the amount of dissolved organic carbon (DOC) in the water increases with increasing lake pH. Increased DOC will reduce water clarity and lead to shallower and more persistent lake thermoclines that can provide larger areas of coldwater thermal refuge habitat. Recovery from acidification will not eliminate the threat of climate change to coldwater fish, but secondary effects of acid recovery may improve the resistance of coldwater fish populations in lakes to the effects of elevated summer temperatures in historically acidified ecosystems. This analysis highlights the importance of considering the legacy of past ecosystem impacts and how recovery or persistence of those effects may interact with climate change impacts on biota in the coming decades.

  9. Great Minds? Great Lakes!

    ERIC Educational Resources Information Center

    Environmental Protection Agency, Chicago, IL. Great Lakes National Program Office.

    This book contains lesson plans that provide an integrated approach to incorporating Great Lakes environmental issues into elementary subjects. The book is divided into three subject areas: (1) History, which includes the origins of the Great Lakes, Great Lakes people, and shipwrecks; (2) Social Studies, which covers government, acid rain as a…

  10. Toxicity of acid mine pit lake water remediated with limestone and phosphorus.

    PubMed

    Neil, Luke L; McCullough, Clint D; Lund, Mark A; Evans, Louis H; Tsvetnenko, Yuri

    2009-11-01

    Pit lakes are increasingly common worldwide and have potential to provide many benefits. However, lake water toxicity may require remediation before beneficial end uses can be realised. Three treatments to remediate AMD (pH approximately 4.8) pit lake water containing elevated concentrations of Al and Zn from Collie, Western Australia were tested in mesocosms. Treatments were: (a) limestone neutralisation (L), (b) phosphorus amendment (P), and (c) combined limestone neutralisation and phosphorus amendment (L+P). Laboratory bioassays with Ceriodaphnia cf. dubia, Chlorella protothecoides and Tetrahymena thermophila assessed remediation. Limestone neutralisation increased pH and reduced heavy metal concentrations by 98% (Al) to 14% (Mg), removing toxicity to the three test species within 2 months. Phosphorus amendment removed toxicity after 6 months of treatment. However, phosphorus amendment to prior limestone neutralisation failed to reduce toxicity more than limestone neutralisation alone. Low concentrations of both phosphorus and nitrogen appear to limit phytoplankton population growth in all treatments.

  11. Toxicity of acid mine pit lake water remediated with limestone and phosphorus

    SciTech Connect

    Neil, L.L.; McCullough, C.D.; Lund, M.A.; Evans, L.H.; Tsvetnenko, Y.

    2009-11-15

    Pit lakes are increasingly common worldwide and have potential to provide many benefits. However, lake water toxicity may require remediation before beneficial end uses can be realised. Three treatments to remediate AMD (pH similar to 4.8) pit lake water containing elevated concentrations of Al and Zn from Collie, Western Australia were tested in mesocosms. Treatments were: (a) limestone neutralisation (L), (b) phosphorus amendment (P), and c) combined limestone neutralisation and phosphorus amendment (L+P). Laboratory bioassays with Ceriodaphnia cf. dubia, Chlorella protothecoides and Tetrahymena thermophila assessed remediation. Limestone neutralisation increased pH and reduced heavy metal concentrations by 98% (Al) to 14% (Mg), removing toxicity to the three test species within 2 months. Phosphorus amendment removed toxicity after 6 months of treatment. However, phosphorus amendment to prior limestone neutralisation failed to reduce toxicity more than limestone neutralisation alone. Low concentrations of both phosphorus and nitrogen appear to limit phytoplankton population growth in all treatments.

  12. Three-dimensional model of the Mono Basin (California): finite element analysis of the interaction between the Hartley Spring Fault and the Mono Dike

    NASA Astrophysics Data System (ADS)

    La Marra, D.; Manconi, A.; McDonnell, A.; Battaglia, M.

    2012-12-01

    Mono Basin is a northward-trending structural depression lying immediately east of the central Sierra Nevada (California) that extends from the northern edge of Long Valley Caldera towards the center of Mono Lake. The Mono-Inyo Craters volcanic chain forms a prominent 17-km-long arcuate ridge within the Mono Basin. Recent studies have proposed that the volcanism and tectonism in this area is likely interrelated. Stratigraphic data suggest that a series of strong earthquakes occurred during the North Mono-Inyo eruption sequence of 1350 A.D. Geological data are consistent with rupture of the Hartley Springs fault during the eruption sequence. The temporal proximity of these events suggests the possibility of a causal relationship. We use the Finite Element Method (FEM) to generate a three-dimensional model of the Mono Basin and investigate the feedback mechanism between dike intrusion and slip along the Hartley Springs fault. First we combine the potential of the FEM with the Okada (1992) analytical solution for a homogeneous elastic flat half-space to validate our model. Then, to better simulate a geodynamic model of the Mono Basin, we implement more realistic dynamics that include gravity forces, vertical and lateral heterogeneities of the crust, and topography. We evaluate the distribution of local stress changes to study the influence of the Inyo dike intrusion on the Hartley Springs fault and how slip along the fault may encourage the propagation of dikes towards the surface. We employ the Coulomb stress change as a failure criterion on the Hartley Springs fault. Preliminary results indicate that slip along the Hartley Springs fault may have encouraged the intrusion of the Mono Dike.

  13. Perfluoroalkyl acids in selected wastewater treatment plants and their discharge load within the Lake Victoria basin in Kenya.

    PubMed

    Chirikona, Florah; Filipovic, Marko; Ooko, Seline; Orata, Francis

    2015-05-01

    A major ecological challenge facing Lake Victoria basin is the influx of chemical contaminants from domestic, hospital, and industrial effluents. Determined levels of perfluoroalkyl acids (PFAAs) in wastewater and sludge from selected wastewater treatment plants (WWTPs) in Kenya are presented and their daily discharge loads calculated for the first time within the Lake Victoria basin. Samples were extracted and separated using solid-phase extraction and ultra-performance liquid chromatography (UPLC)-MS/MS or LC-MS/MS methodology. All sewage sludge and wastewater samples obtained from the WWTPs contained detectable levels of PFAAs in picogram per gram dry weight (d.w.) and in nanogram per liter, respectively. There was variability in distribution of PFAAs in domestic, hospital, and industrial waste with domestic WWPTs observed to contain higher levels. Almost all PFAA homologues of chain length C-6 and above were detected in samples analyzed, with long-chain PFAAs (C-8 and above chain length) being dominant. The discharge from hospital contributes significantly to the amounts of PFAAs released to the municipal water systems and the lake catchment. Using the average output of wastewater from the five WWTPs, a mass load of 1013 mg day(-1) PFAAs per day discharged has been calculated, with the highest discharge obtained at Kisumu City (656 mg day(-1)). The concentration range of perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) in wastewater was 1.3-28 and 0.9-9.8 ng L(-1) and in sludge samples were 117-673 and 98-683 pg g(-1), respectively.

  14. Insights from the Metagenome of an Acid Salt Lake: The Role of Biology in an Extreme Depositional Environment

    PubMed Central

    Johnson, Sarah Stewart; Chevrette, Marc Gerard; Ehlmann, Bethany L.; Benison, Kathleen Counter

    2015-01-01

    The extremely acidic brine lakes of the Yilgarn Craton of Western Australia are home to some of the most biologically challenging waters on Earth. In this study, we employed metagenomic shotgun sequencing to generate a microbial profile of the depositional environment associated with the sulfur-rich sediments of one such lake. Of the 1.5 M high-quality reads generated, 0.25 M were mapped to protein features, which in turn provide new insights into the metabolic function of this community. In particular, 45 diverse genes associated with sulfur metabolism were identified, the majority of which were linked to either the conversion of sulfate to adenylylsulfate and the subsequent production of sulfide from sulfite or the oxidation of sulfide, elemental sulfur, and thiosulfate via the sulfur oxidation (Sox) system. This is the first metagenomic study of an acidic, hypersaline depositional environment, and we present evidence for a surprisingly high level of microbial diversity. Our findings also illuminate the possibility that we may be meaningfully underestimating the effects of biology on the chemistry of these sulfur-rich sediments, thereby influencing our understanding of past geobiological conditions that may have been present on Earth as well as early Mars. PMID:25923206

  15. Long term response of acid-sensitive Vermont Lakes to sulfate deposition

    EPA Science Inventory

    Atmospheric deposition of sulfur can negatively affect the health of lakes and streams, particularly in poorly buffered catchments. In response to the Clean Air Act Amendments, wet deposition of sulfate decreased more than 35% in Vermont between 1990 and 2008. However, most of ...

  16. The use of amino acid analyses in (palaeo-) limnological investigations: A comparative study of four Indian lakes in different climate regimes

    NASA Astrophysics Data System (ADS)

    Menzel, Philip; Anupama, Krishnamurthy; Basavaiah, Nathani; Das, Brijraj Krishna; Gaye, Birgit; Herrmann, Nicole; Prasad, Sushma

    2015-07-01

    In the present study, we report the results of comprehensive amino acid (AA) analyses of four Indian lakes from different climate regimes. We focus on the investigation of sediment cores retrieved from the lakes but data of modern sediment as well as vascular plant, soil, and suspended particulate matter samples from individual lakes are also presented. Commonly used degradation and organic matter source indices are tested for their applicability to the lake sediments, and we discuss potential reasons for possible limitations. A principal component analysis including the monomeric AA composition of organic matter of all analysed samples indicates that differences in organic matter sources and the environmental properties of the individual lakes are responsible for the major variability in monomeric AA distribution of the different samples. However, the PCA also gives a factor that most probably separates the samples according to their state of organic matter degradation. Using the factor loadings of the individual AA monomers, we calculate a lake sediment degradation index (LI) that might be applicable to other palaeo-lake investigations.

  17. Acid-leachable Li and Mg from Lake Cuitzeo sediments in the central Mexico: Paleoclimate change during the past 45 Ka

    NASA Astrophysics Data System (ADS)

    Li, H.; Alcantara, I. I.; Bischoff, J. L.; Wen, D.; Garduño-Monroy, V. H.

    2009-12-01

    Located in Michoacán state of south-central Mexico (19°56’N, 101°5’W), Lake Cuitzeo is an alkaline lake with an area of ~400 km2, average depth of 27m and elevation of 1821m. A 27-m long core was retrieved from the lake, covering about 127-kyr depositional history. The chronology of the upper 9.2m of the core has been reconstructed by radiocarbon dates, showing a continuous deposition during the past 45 Ka. Using 0.5N HCl for leaching the de-ionized water washed lake sediments, we have measured the acid-leachable (AL) elements including Na, K, Li, Mg and Si by ICP-OES. Comparing to the total Si content in bulk sediments ranging from 10 to 40 wt.% with an average of 25.2 ± 4.3 wt.%, the AL Si ranges from 0.064 to 0.375 wt.% with an average of 0.253 ± 0.048 wt.%. The AL Mg content has strongly linear correlation with the total Mg content in the bulk sediments, but accounts for ~55% of the total Mg content. When the carbonate content in the sediment is greater than 10%, the weight loss by the acid-leaching is mainly from dissolution of carbonate. In addition, when the AL Mg is less than 1%, AL Li and AL Mg appear strongly linear correlation. Thus, the AL Li and Mg contents are mainly from authigenic minerals formed in the lake, such as carbonate and sepiolite. When Mg was used up in the lake due to precipitation of carbonate and sepiolite, Li will substitute in sepiolite under the hyper saline and alkaline lake conditions. Therefore, AL Li and Mg contents in the lake sediments can be used as indicators of lake hydrological change under different climatic conditions. High CaCO3%, Li and Mg contents in the periods of 2~12Ka, 19~24Ka, 28~31Ka, 33~34Ka, 35~38Ka and 43~45Ka, indicate higher salinity and alkalinity of the lake hence lower lake levels might be caused by dry and/or warm climates. During 12~20Ka, the lake was relatively fresh and deeper, reflecting cold but wet climatic conditions due to jet stream shifted south during LGM.

  18. Long-term temporal trends and spatial patterns in the acid-base chemistry of lakes in the Adirondack region of New York in response to decreases in acidic deposition

    NASA Astrophysics Data System (ADS)

    Driscoll, Charles T.; Driscoll, Kimberley M.; Fakhraei, Habibollah; Civerolo, Kevin

    2016-12-01

    We examined the response of lake water chemistry in the Adirondack Mountains of New York State, USA to decreases in acid deposition. Striking declines in the concentrations and fluxes of sulfate and hydrogen ion in wet deposition have been observed since the late 1970s, while significant decreases in nitrate have been evident since the early 2000s. Decreases in estimated dry sulfur and nitrate deposition have also occurred in the Adirondacks, but with no change in dry to wet deposition ratios. These patterns follow long-term decreases in anthropogenic emissions of sulfur dioxide and nitrogen oxides in the U.S. over the same interval. All of the 48 lakes monitored through the Adirondack Long-Term Monitoring program since 1992 have exhibited significant declines in sulfate concentrations, consistent with reductions in atmospheric deposition of sulfur. Nitrate concentrations have also significantly diminished at variable rates in many (33 of 48) lakes. Decreases in concentrations of sulfate plus nitrate (48 of 48) in lakes have driven widespread increases in acid neutralizing capacity (ANC; 42 of 48) and lab pH (33 of 48), and decreases in the toxic fraction, inorganic monomeric Al (45 of 48). Coincident with decreases in acid deposition, concentrations of dissolved organic carbon (DOC) have also increased in some (29 of 48) lakes. While recovery from elevated acid deposition is evident across Adirondack lakes, highly sensitive and impacted mounded seepages lakes and thin till drainage lakes are recovering most rapidly. Future research might focus on how much additional recovery could be achieved given the current deposition relative to future deposition anticipated under the Clean Power Plan, ecosystem effects of increased mobilization of dissolved organic matter, and the influence of changing climate on recovery from acidification.

  19. Calcite growth-rate inhibition by fulvic acids isolated from Big Soda Lake, Nevada, USA, The Suwannee River, Georgia, USA and by polycarboxylic acids

    USGS Publications Warehouse

    Reddy, Michael M.; Leenheer, Jerry

    2011-01-01

    Calcite crystallization rates are characterized using a constant solution composition at 25°C, pH=8.5, and calcite supersaturation (Ω) of 4.5 in the absence and presence of fulvic acids isolated from Big Soda Lake, Nevada (BSLFA), and a fulvic acid from the Suwannee River, Georgia (SRFA). Rates are also measured in the presence and absence of low-molar mass, aliphatic-alicyclic polycarboxylic acids (PCA). BSLFA inhibits calcite crystal-growth rates with increasing BSLFA concentration, suggesting that BSLFA adsorbs at growth sites on the calcite crystal surface. Calcite growth morphology in the presence of BSLFA differed from growth in its absence, supporting an adsorption mechanism of calcite-growth inhibition by BSLFA. Calcite growth-rate inhibition by BSLFA is consistent with a model indicating that polycarboxylic acid molecules present in BSLFA adsorb at growth sites on the calcite crystal surface. In contrast to published results for an unfractionated SRFA, there is dramatic calcite growth inhibition (at a concentration of 1 mg/L) by a SRFA fraction eluted by pH 5 solution from XAD-8 resin, indicating that calcite growth-rate inhibition is related to specific SRFA component fractions. A cyclic PCA, 1, 2, 3, 4, 5, 6-cyclohexane hexacarboxylic acid (CHXHCA) is a strong calcite growth-rate inhibitor at concentrations less than 0.1 mg/L. Two other cyclic PCAs, 1, 1 cyclopentanedicarboxylic acid (CPDCA) and 1, 1 cyclobutanedicarboxylic acid (CBDCA) with the carboxylic acid groups attached to the same ring carbon atom, have no effect on calcite growth rates up to concentrations of 10 mg/L. Organic matter ad-sorbed from the air onto the seed crystals has no effect on the measured calcite crystal-growth rates.

  20. Impacts of changing food webs in Lake Ontario: Implications of dietary fatty acids on growth of alewives

    USGS Publications Warehouse

    Snyder, R.J.; Demarche, C.J.; Honeyfield, D.C.

    2011-01-01

    Declines in the abundance and condition of Great Lakes Alewives have been reported periodically during the last two decades, and the reasons for these declines remain unclear. To better understand how food web changes may influence Alewife growth and Wisconsin growth model predictions, we fed Alewives isocaloric diets high in omega-6 fatty acids (corn oil) or high in omega-3 fatty acids (fish oil). Alewives were fed the experimental diets at either 1% ("low ration") or 3% ("high ration") of their wet body weight per day. After six weeks, Alewives maintained on the high ration diets were significantly larger than those fed the low ration diets. Moreover, Alewives given the high ration fish oil diet were significantly larger than those maintained on the high ration corn oil diet after six weeks of growth. Body lipid, energy density and total body energy of Alewives on the high ration diets were significantly higher than those fed the low ration diets, and total body energy was significantly higher in Alewives given the high ration fish oil diet compared to those on the high ration corn oil diet. The current Wisconsin bioenergetics model underestimated growth and overestimated food consumption by Alewives in our study. Alewife thiaminase activity was similar among treatment groups. Overall, our results suggest that future food web changes in Lake Ontario, particularly if they involve decreases in the abundance of lipid rich prey items such as Mysis, may reduce Alewife growth rates and total body energy due to reductions in the availability of dietary omega-3 fatty acids. ?? 2011 AEHMS.

  1. Sediment amino acids as indicators of anthropogenic activities and potential environmental risk in Erhai Lake, Southwest China.

    PubMed

    Ni, Zhaokui; Wang, Shengrui; Zhang, Mianmian

    2016-05-01

    Total hydrolysable amino acids (THAAs) constitute the most important fraction of labile nitrogen. Anthropogenic activities directly influence various biogeochemical cycles and then accelerate lake ecosystem deterioration. This is the first study that has established the relationship between sediment THAAs and anthropogenic activities using dated sediment cores, and evaluated the possibility of THAAs release at the sediment interface based on changes in environmental conditions in Erhai Lake. The results showed that historical distribution and fractions of THAAs could be divided into three stages: a stable period before the 1970s, a clear increasing period from the 1970s to 1990s, and a gradually steady period that started after the 1990s. The chemical fraction, aromatic and sulfur amino acids (AAs) accounted for only ≤3% of THAAs. Basic AAs accounted for 5-17% of THAAs, and remained at a relatively stable level. However, acidic and neutral AAs, which accounted for 19-44% and 35-69% of THAAs, respectively, were the predominant factors causing THAAs to increase due to rapid agricultural intensification and intensification of contemporary sedimentation of phytoplankton or macrophytes since the 1970s. These trends were closely related to both anthropogenic activities and natural processes, which implied that sediment THAAs could act as an effective indicator that reflects anthropogenic activities and aquatic environmental characteristics. The current contributions of sediment THAAs on TN and TOC were <5% and 1.5%, respectively. However, the dramatic increase in THAAs in the sediment cores indicated that there was a huge potential source of labile nitrogen for the overlying water under certain environmental conditions. Correlation analysis suggested that the release of THAAs was negatively correlated with pH, whereas positively correlated with bacterial number and degree of OM mineralization, which particularly depend on the stability of HFOM. Therefore, the risk of

  2. Hazardous crater lakes studied

    NASA Astrophysics Data System (ADS)

    Kusakabe, Minoru

    Crater lakes usually sit on top of volcanic conduits and act as condensers of magmatic vapor. Studies of crater lakes can therefore provide information on both deep magmatic activity and variations in the degassing state of a shallow magmatic body. The Lake Nyos gas disaster of August 1986 and a similar event in August 1984 at Lake Monoun, both in Cameroon, resulted from the accumulation of magmatic CO2 in the bottom layers of the lakes. Geochemical monitoring of crater lakes is a promising tool for forecasting not only limnic but also volcanic eruptions. Acid-mineralized waters formed by condensation of hot magmatic volatiles in crater lakes are thought to bear some resemblance to hydrothermal fluids acting in the genesis of acid-sulfate alteration and Au-Cu-Ag mineralization of volcanic-hosted precious metal deposits.

  3. Amino Acids and Stable Carbon Isotope Distributions in Taihu Lake, China, Over the Last 15,000 Years, and Their Paleoecological Implications

    NASA Astrophysics Data System (ADS)

    Jinquan, Wang; Jinling, Liu

    2000-03-01

    Amino acid, organic nitrogen, and stable carbon isotope (13C/12C) profiles through a core from East Taihu Lake are interpreted in terms of paleoecology and paleoclimate over the last ca. 15,000 yr. Lower amino acid contents and higher δ13C values at the base of the core represent a cool and arid climate, and coincide with low organic productivity. A marked increase in total amino acids and organic nitrogen, with a decrease in δ13C values from 193 to 90 cm (ca. 6500-6000 yr B.P.), indicates a warmer and moist climate, and greater organic productivity. Amino acids then decrease in abundance, while δ13C values increase progressively, beginning at 73 cm (ca. 6000 yr B.P.), reflecting cooling and lower organic productivity. The average δ13C values from a core from West Taihu Lake are evidently higher than values from East Taihu Lake. The latter may reflect a stream environment, whereas the high δ13C values from West Taihu Lake likely reflect autotrophic carbon sources and a lacustrine environment since 11,000 yr B.P.

  4. New insights into the source of decadal increases of dissolved organic matter in acid-sensitive lakes of the Northeastern U.S.

    EPA Science Inventory

    The last several decades have seen decreases in SO42- deposition across the northeastern United States. As a result, SO42- concentrations in lakes and streams have also decreased and many surface water bodies have become less acidic. During the same time period, there has been ...

  5. Preliminary measurements of summer nitric acid and ammonia concentrations in the Lake Tahoe Basin air-shed: implications for dry deposition of atmospheric nitrogen.

    PubMed

    Tarnay, L; Gertler, A W; Blank, R R; Taylor, G E

    2001-01-01

    Over the past 50 years, Lake Tahoe, an alpine lake located in the Sierra Nevada mountains on the border between California and Nevada, has seen a decline in water clarity. With significant urbanization within its borders and major urban areas 130 km upwind of the prevailing synoptic airflow, it is believed the Lake Tahoe Basin is receiving substantial nitrogen (N) input via atmospheric deposition during summer and fall. We present preliminary inferential flux estimates to both lake surface and forest canopy based on empirical measurements of ambient nitric acid (HNO3), ammonia (NH3), and ammonium nitrate (NH4NO3) concentrations, in an effort to identify the major contributors to and ranges of atmospheric dry N deposition to the Lake Tahoe Basin. Total flux from dry deposition ranges from 1.2 to 8.6 kg N ha-1 for the summer and fall dry season and is significantly higher than wet deposition, which ranges from 1.7 to 2.9 kg N ha-1 year-1. These preliminary results suggest that dry deposition of HNO3 is the major source of atmospheric N deposition for the Lake Tahoe Basin, and that overall N deposition is similar in magnitude to deposition reported for sites exposed to moderate N pollution in the southern California mountains.

  6. Magmatic storage conditions along the Mono Craters chain, Eastern California

    NASA Astrophysics Data System (ADS)

    Williams, M.; Befus, K.; Gardner, J. E.

    2012-12-01

    We employ a variety of petrologic tools to characterize the pre-eruptive storage conditions of individual units erupted from Mono Craters. The Mono Craters chain represents one of the systems within the Long Valley volcanic field in Eastern California, which has been a regional center for effusive to cataclysmic volcanism from 800 ka until recent times. The Long Valley system has been the focus of much research; however, there are little published petrologic data for the Mono Craters chain. Understanding the Mono Craters chain is critical because it was the center for the most recent eruptions in the region. Eruptions along the chain occurred from 20 ka to ~660 years ago, and it is the most likely focus for future volcanic activity in the Long Valley region. Thus, petrologic data from Mono Craters must provide excellent constraints on the development and nature of the existing magmatic system. The Mono Craters chain contains 27 high silica rhyolite domes and flows and 1 dacite dome that were erupted along a gently arcuate trend that extends for ~15 km south of Mono Lake. The high silica rhyolites can be subdivided based on phenocryst assemblages into the following groups: biotite-bearing rhyolite, orthopyroxene-bearing rhyolite, fayalite-bearing rhyolite, sparsely porphyritic rhyolite, and aphyric rhyolite. We collected samples from 14 of the domes and flows within the Mono Craters chain, obtaining samples from each of the groups except the orthopyroxene-bearing rhyolite. We examined the composition of the mineral phases using electron microprobe analyses. Biotite-bearing rhyolites contain phenocrysts of quartz, plagioclase (Ab74-77), sanidine (Or66-68), Fe-rich hornblende, Ti-rich biotite, pyroxene, and magnetite with lamellae of ilmenite. Fayalite-bearing rhyolites contain phenocrysts of quartz, plagioclase (Ab75-80), sanidine (Or61-69), fayalite (Fa92-93), Fe-rich hornblende, Ti-rich biotite, pyroxene, magnetite and ilmenite. Sparsely porphyritic rhyolites

  7. The Magma Transport System of the Mono Craters, California

    NASA Astrophysics Data System (ADS)

    Johnson, M. R.; Putirka, K. D.

    2013-12-01

    The Mono Craters are a series of 28 volcanic domes, coulees, and craters, just 16 km north of Long Valley. The magmatic products of the Mono Craters include mostly small magmatic bodies, sills, and dikes set in a transtensional tectonic setting. New high-density sampling of the domes reveals a wider range of magma compositions than heretofore recognized, and thus reveals what is likely a more complex magmatic system, involving a greater number of batches of magma and a more complex magma storage/delivery system. Here, we present a model for the magma plumbing system based on space-composition patterns and preliminary estimates of crystallization temperatures and pressures based on olivine-, feldspar- and clinopyroxene-liquid equilibria. Whole rock analyses show three compositionally distinct batches of magma within the Mono Craters proper: a felsic (73-78.4% SiO2), intermediate (64.4-68% SiO2) and mafic (52.7-61% SiO2) group. The Mono Lake Islands (Paoha and Negit) fall into the intermediate group, but contain distinctly lower TiO2 and Fe2O3 at a given SiO2 compared to all other Mono Craters; on this basis, we surmise that the Paoha and Negit eruptions represent a distinct episode of magmatism that is not directly related to the magmatic activity that created the Mono Craters proper. The discontinuous nature of the three groups indicates that magma mixing, while evident to some degree within and between certain domes, did not encompass the entire range of compositions at any given time. The three groups, however, do form a rough linear trend, and some subsets of domes have compositions that fall on distinctly linear (if still discontinuous) trends that cannot be reproduced by fractional crystallization, but rather are indicative of magma mixing. Our high-density sampling also reveals interesting geographical patterns: for example, felsic magmas erupt throughout the entire Mono Craters chain, erupting at a wide range of temperatures, ranging from 650-995°C, but

  8. Contemporaneous deposition of phyllosilicates and sulfates: Using Australian acidic saline lake deposits to describe geochemical variability on Mars

    USGS Publications Warehouse

    Baldridge, A.M.; Hook, S.J.; Crowley, J.K.; Marion, G.M.; Kargel, J.S.; Michalski, J.L.; Thomson, B.J.; de Souza, Filho C.R.; Bridges, N.T.; Brown, A.J.

    2009-01-01

    Studies of the origin of the Martian sulfate and phyllosilicate deposits have led to the hypothesis that there was a marked, global-scale change in the Mars environment from circum-neutral pH aqueous alteration in the Noachian to an acidic evaporitic system in the late Noachian to Hesperian. However, terrestrial studies suggest that two different geochemical systems need not be invoked to explain such geochemical variation.Western Australian acidic playa lakes have large pH differences separated vertically and laterally by only a few tens of meters, demonstrating how highly variable chemistries can coexist over short distances in natural environments. We suggest diverse and variable Martian aqueous environments where the coetaneous formation of phyllosilicates and sulfates at the Australian sites are analogs for regions where phyllosilicates and sulfates coexist on Mars. In these systems, Fe and alkali earth phyllosilicates represent deep facies associated with upwelling neutral to alkaline groundwater, whereas aluminous phyllosilicates and sulfates represent near-surface evaporitic facies formed from more acidic brines. Copyright 2009 by the American Geophysical Union.

  9. Contemporaneous deposition of phyllosilicates and sulfates: Using Australian acidic saline lake deposits to describe geochemical variability on Mars

    NASA Astrophysics Data System (ADS)

    Baldridge, A. M.; Hook, S. J.; Crowley, J. K.; Marion, G. M.; Kargel, J. S.; Michalski, J. L.; Thomson, B. J.; de Souza Filho, C. R.; Bridges, N. T.; Brown, A. J.

    2009-10-01

    Studies of the origin of the Martian sulfate and phyllosilicate deposits have led to the hypothesis that there was a marked, global-scale change in the Mars environment from circum-neutral pH aqueous alteration in the Noachian to an acidic evaporitic system in the late Noachian to Hesperian. However, terrestrial studies suggest that two different geochemical systems need not be invoked to explain such geochemical variation. Western Australian acidic playa lakes have large pH differences separated vertically and laterally by only a few tens of meters, demonstrating how highly variable chemistries can coexist over short distances in natural environments. We suggest diverse and variable Martian aqueous environments where the coetaneous formation of phyllosilicates and sulfates at the Australian sites are analogs for regions where phyllosilicates and sulfates coexist on Mars. In these systems, Fe and alkali earth phyllosilicates represent deep facies associated with upwelling neutral to alkaline groundwater, whereas aluminous phyllosilicates and sulfates represent near-surface evaporitic facies formed from more acidic brines.

  10. Application of a continuous distribution model for proton binding by humic acids extracted from acidic lake sediments

    SciTech Connect

    Rhea, J.R.; Young, T.C. )

    1987-01-01

    The proton binding characteristics of humic acids extracted from the sediments of Cranberry Pond, an acidic water body located in the Adirondack Mountain region of New York State, were explored by the application of a nultiligand distribution model. The model characterizes a class of proton binding sites by mean log K values and the standard deviations of log K values and the mean. Mean log K values and their relative abundances were determined directly from experimental titration data. The model accurately predicts the binding of protons by the humic acids for pH values in the range 3.5 to 10.0.

  11. Application of a continuous distribution model for proton binding by humic acids extracted from acidic lake sediments

    NASA Astrophysics Data System (ADS)

    Rhea, James R.; Young, Thomas C.

    1987-10-01

    The proton binding characteristics of humic acids extracted from the sediments of Cranberry Pond, an acidic water body located in the Adirondack Mountain region of New York State, were explored by the application of a multiligand distribution model. The model characterizes a class of proton binding sites by mean log K values and the standard deviations of log K values about the mean. Mean log K values and their relative abundances were determined directly from experimental titration data. The model accurately predicts the binding of protons by the humic acids for pH values in the range 3.5 to 10.0.

  12. Fatty Acid Composition and Levels of Selected Polyunsaturated Fatty Acids in Four Commercial Important Freshwater Fish Species from Lake Victoria, Tanzania

    PubMed Central

    Robert, Agnes; Mfilinge, Prosper; Limbu, Samwel M.; Mwita, Chacha J.

    2014-01-01

    Fatty acids (FAs) particularly ω3 and ω6 polyunsaturated fatty acids (PUFAs) play important role in human health. This study aimed to investigate the composition and levels of selected ω3 PUFAs in four commercial fish species, Nile perch (Lates niloticus), Nile tilapia (Oreochromis niloticus), Tilapia zillii, and dagaa (Rastrineobola argentea) from Mwanza Gulf in Lake Victoria. The results indicated that 36 types of FAs with different saturation levels were detected. These FAs were dominated by docosahexaenoic (DHA), eicosapentaenoic (EPA), docosapentaenoic (DPA), and eicosatetraenoic acids. O. niloticus had the highest composition of FAs (34) compared to L. niloticus (27), T. zillii (26), and R. argentea (21). The levels of EPA differed significantly among the four commercial fish species (F = 6.19,  P = 0.001). The highest EPA levels were found in R. argentea followed by L. niloticus and O. niloticus and the lowest in T. zillii. The DPA levels showed no significant difference among the four fish species studied (F = 0.652,  P = 0.583). The study concluded that all four commercial species collected from Mwanza Gulf are good for human health, but R. argentea is the best for consumption because it contains higher levels of ω3 FAs, mainly EPA. PMID:25610654

  13. Variation in fatty acid composition in muscle and heart tissues among species and populations of tropical fish in Lakes Victoria and Kyoga.

    PubMed

    Kwetegyeka, Justus; Mpango, George; Grahl-Nielsen, Otto

    2008-11-01

    The composition of the fatty acids in muscle and heart tissue of seven fish species, Nile perch (Lates niloticus), Nile tilapia (Oreochromis niloticus), marbled lungfish (Protopterus aethiopicus), African catfish (Clarias gariepinus), Lake Victoria squeaker (Synodontis victoriae), Bagrus docmas, and Tilapia zilli, from two locations in Lake Kyoga and one location in Lake Victoria was chemometrically determined. The muscle tissue was very lean, with an average of 3.4 mg total fatty acids per g tissue. The lipid level in the heart tissue was approximately five times higher than in the muscle tissue, with an average of 15.5 mg total fatty acids per g tissue. The n-3/n-6 level in the muscles was 1.7 +/- 0.7 and in the heart tissue 1.0 +/- 0.4. The muscle tissue contained an average of 46 mg cholesterol per 100 g, and the heart tissue contained about five times as much. Plasmalogens were detected in 7-8% of the amounts of total fatty acids in both muscle and heart tissue. The seven species had large differences (P < 0.05) in the fatty acid composition for both muscle and heart tissue. Within the species there were differences between fish from the populations in the three locations, although the population differences were smaller than the species differences. These differences appear to be controlled more closely by genetics/transcriptomics than by the diet.

  14. Mineralogical and Chemical Characterization of Acidic Pumices Outcrop North of Lake Van

    NASA Astrophysics Data System (ADS)

    Yucel, Aysegul; Efe, Tugba; Onal, Mehmet; Depci, Tolga; Aydin, Harun

    2016-10-01

    In the present study, mineralogical, physical and chemical characteristics of the pumice located in North of Lake Van locations were investigated to find an applicability of them for cement and textile industry. Characterization studies of the pumice samples were carried out by thin section, SEM, XRF, XRD and FTIR analysis. In addition, the bulk density, Hard Grove Index (HGI), pozzolanic activity and reactive silica of the pumice samples were determined. The overall results showed that the pumice samples, which might be an eruption product of Mount Suphan, had an amorphous structure and rhyolite composition in high calc- alkaline series. The chemical compositions and physical properties indicated that the pumice samples could be used in cement and textile industry.

  15. Impact of acid effluent from Kawah Ijen crater lake on irrigated agricultural soils: Soil chemical processes and plant uptake

    NASA Astrophysics Data System (ADS)

    van Rotterdam-Los, A. M. D.; Heikens, A.; Vriend, S. P.; van Bergen, M. J.; van Gaans, P. F. M.

    2008-12-01

    Volcanogenic contamination of irrigation water, caused by effluent from the hyperacid Ijen crater lake, has severely affected the properties of agricultural soils in East Java, Indonesia. From a comparison of acidified topsoil with subsoil and with top- and subsoil in a reference area, we identified processes responsible for changes in soil and soil solution chemistry induced by acid irrigation water, with emphasis on the nutrients Ca, Mg, Fe, and Mn, and on Al, which may become phytotoxic under acid conditions in soils. Compositional data for bulk soil composition and selective extractions with 1 M KCl and 0.2 M acid ammonium oxalate are used in a mass balance approach to specify element fluxes, including uptake by rice plants. The results show that input via irrigation water has produced an increase in the total aluminum content in the affected topsoil, which is of the same order of magnitude as the increase in labile Al. High bioavailability of Al, as reflected by concentrations in KCl extracts, is consistent with elevated concentrations observed in rice plants. In contrast, and despite the high input via irrigation water, Ca and Mg concentrations have decreased in all measured soil fractions through dissolution of amorphous phases and minerals, and through competition of Al for adsorption sites on the exchange complex and plant roots. Strong leaching is also evident for Fe and especially Mn. In terms of the overall mass balance of the topsoil, plant uptake of Al, Ca, Fe, Mg and Mn is negligible. If the use of acid irrigation would be stopped and the soil pH were to increase to values above 4.5, the observed phytotoxicity of Al will be halted. However, crops may then become fully dependent on the input from irrigation water or fertilizer for essential elements, due to the previous removal from the topsoil through leaching.

  16. Investigation of low-molecular weight organic acids and their spatiotemporal variation characteristics in Hongfeng Lake, China.

    PubMed

    Xiao, Min; Wu, Fengchang; Wang, Liying; Li, Xinqing; Huang, Rongsheng

    2013-02-01

    The identities and concentrations of low-molecular-weight organic acids (LMWOAs) were determined by ion chromatography throughout a 20-m water column in Hongfeng Lake, China. The spatiotemporal variations of LMWOAs and their contributions to dissolved organic matter (DOM) in a research period of 24 hr were also investigated. The results demonstrated that five LMWOAs (lactic, acetic, pyruvic, sorbic, oxalic acid) were detected, and their total concentration and proportion in DOC were 6.55 micromol/L and 7.47%. Their average levels were 2.50, 0.65, 2.35, 0.96 and 0.09 micromol/L, respectively. LMWOAs were higher during daytime (10:00-18:00 on Jun 13, 2008) than nighttime (21:00-6:00 the next morning), in particular 4.99 micromol/L high in the epilimnion (< or = 1 m water depth), reflecting the fact that direct import from terrigenous sources and photochemical production from humic materials were dominant during LMWOAs' origin and accumulation. The same factors caused LMWOAs to be 0.63 micromol/L in the epilimnion higher than in the hypolimnion. The rapid decrease of total organic acid (TOA) up until 18:00 mainly resulted from bio-uptake and mineralization in the hypolimnion (>1 m water depth). Pyruvic acid increased with time in the epilimnion and decreased in the hypolimnion, largely related to the two contrary processes of continuous degradation and synthesis of macromolecular organic matter during life materials' cycle mediated by organisms. Simultaneously, plankton behavior and thermal stratification played a pivotal role in LMWOAs' behavior in the water column, causing decreasing and increasing profiles. The distribution of LMWOAs represents an interesting resource for biogeochemical research of DOM in aquatic ecosystems.

  17. Factors determining growth and vertical distribution of planktonic algae in extremely acidic mining lakes (pH 2.7)

    NASA Astrophysics Data System (ADS)

    Bissinger, Vera

    2003-04-01

    In this thesis, I investigated the factors influencing the growth and vertical distribution of planktonic algae in extremely acidic mining lakes (pH 2-3). In the focal study site, Lake 111 (pH 2.7; Lusatia, Germany), the chrysophyte, Ochromonas sp., dominates in the upper water strata and the chlorophyte, Chlamydomonas sp., in the deeper strata, forming a pronounced deep chlorophyll maximum (DCM). Inorganic carbon (IC) limitation influenced the phototrophic growth of Chlamydomonas sp. in the upper water strata. Conversely, in deeper strata, light limited its phototrophic growth. When compared with published data for algae from neutral lakes, Chlamydomonas sp. from Lake 111 exhibited a lower maximum growth rate, an enhanced compensation point and higher dark respiration rates, suggesting higher metabolic costs due to the extreme physico-chemical conditions. The photosynthetic performance of Chlamydomonas sp. decreased in high-light-adapted cells when IC limited. In addition, the minimal phosphorus (P) cell quota was suggestive of a higher P requirement under IC limitation. Subsequently, it was shown that Chlamydomonas sp. was a mixotroph, able to enhance its growth rate by taking up dissolved organic carbon (DOC) via osmotrophy. Therefore, it could survive in deeper water strata where DOC concentrations were higher and light limited. However, neither IC limitation, P availability nor in situ DOC concentrations (bottom-up control) could fully explain the vertical distribution of Chlamydomonas sp. in Lake 111. Conversely, when a novel approach was adopted, the grazing influence of the phagotrophic phototroph, Ochromonas sp., was found to exert top-down control on its prey (Chlamydomonas sp.) reducing prey abundance in the upper water strata. This, coupled with the fact that Chlamydomonas sp. uses DOC for growth, leads to a pronounced accumulation of Chlamydomonas sp. cells at depth; an apparent DCM. Therefore, grazing appears to be the main factor influencing the

  18. Air pollutin and acid rain, Report 4. Effects of air pollution and acid rain on fish, wildlife, and their habitats - lakes

    SciTech Connect

    Potter, W.; Adler, D.

    1982-06-01

    This report summarizes the results of scientific research related to air pollution effects on fish and wildlife associated with lakes and wetlands. The effects of photochemical oxidants, particulates, and acidifying air pollutants on water quality and lake and wetland biota are summarized. The characteristics that indicate lake sensitivity to air pollutants, in particular acidifying pollutants, are presented. Socioeconomic aspects of air pollution impacts on lake ecosystems are discussed and areas of research are suggested to increase the understanding of the effects of air pollutants on lake and wetland ecosystems. 172 references, 1 figure, 6 tables.

  19. Connections between hyper-acid crater lakes and flank springs: new evidence from Rincón de la Vieja volcano (Costa Rica)

    NASA Astrophysics Data System (ADS)

    Martínez, M.; Fernández, E.; Sáenz, W.; van Bergen, M. J.; Ayres, G.; Pacheco, J. F.; Brenes, J.; Avard, G.; Malavassi, E.

    2012-04-01

    Rincón de la Vieja, a complex andesitic stratovolcano in NW Costa Rica, shows various hydrothermal surface manifestations that comprise: (1) A hyper-acid crater lake and subaerial fumaroles receiving direct input of fluids of magmatic origin, (2) Acid thermal discharges along the northeastern slopes of the volcano that feed the headwaters of the Cucaracho river, and (3) Small lakes and a geothermal field with bubbling-boiling mud pools, acid-sulfate springs, steaming ground and fumarolic emissions in a region on the western flank. Here the streams are of relatively low flow rate and their chemical signatures correspond to that of deep fluids from an extensive geothermal reservoir mixed with shallow meteoric water. Physico-chemical properties of the sulfate-chloride hyper-acid lake (T=28-58 °C; pH between 1.2 and <0, high TDS of 24,000-160,000 mg/kg) are consistent with a meteoric water body supplied by a significant input of chemical components derived from hydrolysis of magmatic volatiles and from intense rock leaching. The Cucaracho catchment receives input from warm acid brines with no free-gas phase but carrying a high load of hydrolyzed magmatic volatiles and rock-forming elements. One of these brines (Spring 4) is characterized by a sulfate-chloride chemical signature, medium temperatures of 27-38 °C, pH between 2 and 4 and TDS values between 780 and 1300 mg/L. Based on water and heat-balance considerations, chemical and stable-isotope signatures and groundwater transport modeling, it has been proposed that these acid springs represent brine water from the lake-hydrothermal system that is diluted by shallow groundwater permeating tephra layers (Kempter and Rowe, 2000). Since Rincóńs latest phreatomagmatic activity in 1983, episodes of phreatic eruptions from the crater lake have been registered in 1983-87, 1991, 1995, 1998 and 2011. Some of these eruptions (VEI 1) have expelled large quantities of lake water, triggering small to medium- sized fast

  20. Differences in activation of aryl hydrocarbon receptors of white sturgeon relative to lake sturgeon are predicted by identities of key amino acids in the ligand binding domain.

    PubMed

    Doering, Jon A; Farmahin, Reza; Wiseman, Steve; Beitel, Shawn C; Kennedy, Sean W; Giesy, John P; Hecker, Markus

    2015-04-07

    Dioxin-like compounds (DLCs) are pollutants of global environmental concern. DLCs elicit their adverse outcomes through activation of the aryl hydrocarbon receptor (AhR). However, there is limited understanding of the mechanisms that result in differences in sensitivity to DLCs among different species of fishes. Understanding these mechanisms is critical for protection of the diversity of fishes exposed to DLCs, including endangered species. This study investigated specific mechanisms that drive responses of two endangered fishes, white sturgeon (Acipenser transmontanus) and lake sturgeon (Acipenser fulvescens) to DLCs. It determined whether differences in sensitivity to activation of AhRs (AhR1 and AhR2) can be predicted based on identities of key amino acids in the ligand binding domain (LBD). White sturgeon were 3- to 30-fold more sensitive than lake sturgeon to exposure to 5 different DLCs based on activation of AhR2. There were no differences in sensitivity between white sturgeon and lake sturgeon based on activation of AhR1. Adverse outcomes as a result of exposure to DLCs have been shown to be mediated through activation of AhR2, but not AhR1, in all fishes studied to date. This indicates that white sturgeon are likely to have greater sensitivity in vivo relative to lake sturgeon. Homology modeling and in silico mutagenesis suggests that differences in sensitivity to activation of AhR2 result from differences in key amino acids at position 388 in the LBD of AhR2 of white sturgeon (Ala-388) and lake sturgeon (Thr-388). This indicates that identities of key amino acids in the LBD of AhR2 could be predictive of both in vitro activation by DLCs and in vivo sensitivity to DLCs in these, and potentially other, fishes.

  1. Enhanced Resolution of Chiral Amino Acids with Capillary Electrophoresis for Biosignature Detection in Extraterrestrial Samples.

    PubMed

    Creamer, Jessica S; Mora, Maria F; Willis, Peter A

    2017-01-17

    Amino acids are fundamental building blocks of terrestrial life as well as ubiquitous byproducts of abiotic reactions. In order to distinguish between amino acids formed by abiotic versus biotic processes it is possible to use chemical distributions to identify patterns unique to life. This article describes two capillary electrophoresis methods capable of resolving 17 amino acids found in high abundance in both biotic and abiotic samples (seven enantiomer pairs d/l-Ala, -Asp, -Glu, -His, -Leu, -Ser, -Val and the three achiral amino acids Gly, β-Ala, and GABA). To resolve the 13 neutral amino acids one method utilizes a background electrolyte containing γ-cyclodextrin and sodium taurocholate micelles. The acidic amino acid enantiomers were resolved with γ-cyclodextrin alone. These methods allow detection limits down to 5 nM for the neutral amino acids and 500 nM for acidic amino acids and were used to analyze samples collected from Mono Lake with minimal sample preparation.

  2. Investigations of the Origin of the Magnetic Remanence in Late Pleistocene Lacustrine Sediments in the Mono Basin, CA

    NASA Astrophysics Data System (ADS)

    Vasquez, N.; Corley, A. D.

    2015-12-01

    In the Mono Basin, CA, fine sand, silt, and volcanic ash deposited in Pleistocene Lake Russell is exposed on the margin of Mono Lake, and on Paoha Island in the lake. The silt records the Mono Lake Excursion (MLE: Denham and Cox, 1971) and several tens of thousands of years of paleomagnetic secular variation (PSV: Denham and Cox, 1971; Liddicoat, 1976; Lund et al., 1988). The sediment is believed to be an accurate recorder of PSV because the MLE has the same signal at widely separated localities in the basin (Denham, 1974; Liddicoat and Coe, 1979; Liddicoat, 1992) with the exception at wave-cut cliffs on the southeast side of the lake (Coe and Liddicoat, 1994). Magnetite, titanomagnetite, and titanomaghemite are present in the sediment (Denham and Cox, 1971; Liddicoat, 1976; Liddicoat and Coe, 1979), which is glacial flour from the adjacent Sierra Nevada (Lajoie, 1968). X-rays of the sediment and lineation measurements show patterns of normal bedding with layers aligned such that the minimum axes are within 5-10 degrees of normal bedding, with 10 percent foliation and 1 percent lineation (Coe and Liddicoat, 1994). We explore reasons for the difference in part of the PSV record at the wave-cut cliffs beyond the interpretation of Coe and Liddicoat (1994) that paleomagnetic field strength is a controlling factor. Possibilities include the sedimentation rate - at localities on the margin of Mono Lake the rate is about 60 percent less than at the wave-cut cliffs - and lithology of the sediment. At Mill Creek on the northwest side of Mono Lake, the non-magnetic sediment fraction is coarser-grained than at the wave-cut cliffs by a factor of about two, and there is a similar difference in the total inorganic carbon (TIC) percentage by weight for the two localities. (Spokowski et al., 2011) Studies of the sediment at two localities in the basin where the Hilina Pali Excursion (Teanby et al., 2002) might be recorded (Wilson Creek and South Shore Cliffs; Liddicoat and Coe

  3. High-resolution aeromagnetic survey of the Mono Basin-Long Valley Caldera region, California

    NASA Astrophysics Data System (ADS)

    Ponce, D. A.; Mangan, M.; McPhee, D.

    2013-12-01

    A new high-resolution aeromagnetic survey of the Mono Basin-Long Valley Caldera region greatly enhances previous magnetic interpretations that were based on older, low-resolution, and regional aeromagnetic data sets and provides new insights into volcano-tectonic processes. The surveyed area covers a 8,750 km2 NNW-trending swath situated between the Sierra Nevada to the west and the Basin and Range Province to the east. The surveyed area includes the volcanic centers of Mono Lake, Mono-Inyo Craters, Mammoth Mountain, Devils Postpile, and Long Valley Caldera. The NW-trending eastern Sierra frontal fault zone crosses through the study area, including the active Mono Lake, Silver Lake, Hartley Springs, Laurel Creek, and Hilton Creek faults. Over 6,000 line-kilometers of aeromagnetic data were collected at a constant terrain clearance of 150 m, a flight-line spacing of 400 m, and a tie-line spacing of 4 km. Data were collected via helicopter with an attached stinger housing a magnetic sensor using a Scintrex CS-3 cesium magnetometer. In the northern part of the survey area, data improve the magnetic resolution of the individual domes and coulees along Mono Craters and a circular shaped magnetic anomaly that coincides with a poorly defined ring fracture mapped by Kistler (1966). Here, aeromagnetic data combined with other geophysical data suggests that Mono Craters may have preferentially followed a pre-existing plutonic basement feature that may have controlled the sickle shape of the volcanic chain. In the northeastern part of the survey, aeromagnetic data reveal a linear magnetic anomaly that correlates with and extends a mapped fault. In the southern part of the survey, in the Sierra Nevada block just south of Long Valley Caldera, aeromagnetic anomalies correlate with NNW-trending Sierran frontal faults rather than to linear NNE-trends observed in recent seismicity over the last 30 years. These data provide an important framework for the further analysis of the

  4. Stochastic modeling of Lake Van water level time series with jumps and multiple trends

    NASA Astrophysics Data System (ADS)

    Aksoy, H.; Unal, N. E.; Eris, E.; Yuce, M. I.

    2013-06-01

    In the 1990s, water level in the closed-basin Lake Van located in the Eastern Anatolia, Turkey, has risen up about 2 m. Analysis of the hydrometeorological data shows that change in the water level is related to the water budget of the lake. In this study, stochastic models are proposed for simulating monthly water level data. Two models considering mono- and multiple-trend time series are developed. The models are derived after removal of trend and periodicity in the dataset. Trend observed in the lake water level time series is fitted by mono- and multiple-trend lines. In the so-called mono-trend model, the time series is treated as a whole under the hypothesis that the lake water level has an increasing trend. In the second model (so-called multiple-trend), the time series is divided into a number of segments to each a linear trend can be fitted separately. Application on the lake water level data shows that four segments, each fitted with a trend line, are meaningful. Both the mono- and multiple-trend models are used for simulation of synthetic lake water level time series under the hypothesis that the observed mono- and multiple-trend structure of the lake water level persist during the simulation period. The multiple-trend model is found better for planning the future infrastructural projects in surrounding areas of the lake as it generates higher maxima for the simulated lake water level.

  5. Microbial heterotrophic production in an oligotrophic acidic geothermal lake: responses to organic amendments and terrestrial plant litter.

    PubMed

    Wolfe, Gordon V; Fitzhugh, Connor; Almasary, Areeje; Green, Adrian; Bennett, Patrick; Wilson, Mark; Siering, Patricia

    2014-09-01

    Boiling Springs Lake (BSL) is an oligotrophic, acidic geothermal feature where even very low levels of microbial heterotrophic production still exceed autotrophy. To test whether allochthonous leaf litter (LL) inputs fuel this excess, we quantified leaf litterfall, leaching and decomposition kinetics, and measured the impact of organic amendments on production, germination and cell growth, using pyrosequencing to track changes in microbial community composition. Coniferous leaves in BSL exhibited high mass loss rates during leaching and decomposition, likely due to a combination of chemical hydrolysis and contributions of both introduced and endemic microbes. We measured very low in situ (3)H-thymidine incorporation over hours by the dominant chemolithotroph Acidimicrobium (13-65 μg C L(-1) day(-1)), which was inhibited by simple C sources (acetate, glucose). Longer term incubations with additions of 0.01-0.02% complex C/N sources induced germination of the Firmicute Alicyclobacillus within 1-2 days, as well as growth of Acetobacteraceae after 3-4 days. LL additions yielded the opposite successional patterns of these r-selected heterotrophs, boosting production to 30-150 μg C L(-1) day(-1). Growth and germination studies suggest both prokaryotes and fungi likely consume allochthonous organics, and might be novel sources of lignocellulose-degrading enzymes. A model of BSL's C budget supports the hypothesis that allochthonous inputs fuel seasonal microbial heterotrophy, but that dissolved organic C sources greatly exceed direct LL inputs.

  6. Mineralogy of evaporite deposits on Mars: Constraints from laboratory, field, and remote measurements of analog terrestrial acid saline lakes

    NASA Astrophysics Data System (ADS)

    Bridges, N.; Núñez, J. I.; Seelos, F. P., IV; Hook, S. J.; Baldridge, A. M.; Thomson, B. J.

    2015-12-01

    Remote compositional data from imaging spectrometers such as CRISM, OMEGA, and TES, and high-resolution imagery from MOC, CTX, and HiRISE have provided invaluable information for improving our understanding of the composition and geologic history of the martian surface and identifying potential past and present habitable environments on Mars. Simulated CRISM spectra and summary parameter maps and HiRISE color images were generated using airborne hyperspectral data of two acid-saline lakes in Western Australia. These locations are applicable to Mars, as they contain a suite of clays, sulfates, and salts formed under variable pH and salinity - mineralogies similar to those observed in Noachian and Hesperian terrain. The remote datasets were used to make surface composition predictions which were then verified through field study and sample analysis. We find phyllosilicates intermixed with sulfates in sulfate-rich surfaces exhibit variable spectral responses, even for similar conditions and abundances seen in the field. Where sulfates, such as gypsum and alunite, are found, phyllosilicates are intermixed or reside beneath the surface yet are not always detected. This suggests that geologic complexities may mask phyllosilicate detection at or near the surface on Mars where only sulfates have so far been found.

  7. Anaerobic decomposition of cellulose by allcaliphilic microbial Community of Owens Lake, California

    NASA Technical Reports Server (NTRS)

    Pikuta, Elena V.; Itoh, Takashi; Hoover, Richard B.

    2005-01-01

    The study of communities of microbial extremophiles from anaerobic sediments of Owens Lake and Mono Lake in California has established the presence of active microbial cellulolytic processes in both lakes. The prior study of the microbial diversity in Mono Lake showed that the trophic chain of organic decomposition includes secondary anaerobes that were found to be previously unknown species (Spirochaeta americana, Tindallia californiensis, and Desulfonatronum thiodismutans). And as we published earlier, the secondary anaerobes of Owens Lakes were morphologically very similar to those of Mono Lake. However, continuing comparison of the physiology and genetics has led to the conclusion that some links of organic decomposition in the trophic chain of Owens Lake are represented by different unknown species. A new isolate of a sugarlytic spirochete from Owens Lake, which was morphologically very similar to S. americana isolated from Mono Lake, was found to have different metabolic capacity such as the lack of capability to produce hydrogen during glucose fermentation. Furthermore, from the same bacterial community (from Owens Lake) another sugarlytic spore-forming alkaliphile (strain SCA) was isolated in pure culture. Here we discuss the geology and chemistry of Owens Lake as a unique ecosystem of Astrobiological significance. This paper also presents some of the characteristics for the novel isolates and describes their participation in the process of cellulose degradation.

  8. Embryotoxicity of an extract from Great Lakes lake trout to rainbow trout and lake trout

    SciTech Connect

    Wright, P.J.; Tillitt, D.E.

    1995-12-31

    Aquatic ecosystems such as the Great Lakes are known to be contaminated with chemicals that are toxic to fish. However, the role of these contaminants in reproductive failures of fishes, such as lake trout recruitment, has remained controvertible. It was the objective to evaluate dioxin-like embryotoxicity of a complex mixture of chemicals and predict their potential to cause the lack of recruitment in Great Lakes lake trout. Graded doses of a complex environmental extract were injected into eggs of both rainbow trout and lake trout. The extract was obtained from whole adult lake trout collected from Lake Michigan in 1988. The extract was embryotoxic in rainbow trout, with LD50 values for Arlee strain and Erwin strain of 33 eggEQ and 14 eggEQ respectively. The LOAEL for hemorrhaging, yolk-sac edema, and craniofacial deformities in rainbow trout were 2, 2, and 4 eggEQ, respectively. Subsequent injections of the extract into lake trout eggs were likewise embryotoxic, with an LD50 value of 7 eggEQ. The LOAEL values for the extract in lake trout for hemorrhaging, yolk-sac edema, and craniofacial deformities were 0.1, 1, and 2 eggEQ, respectively. The current levels of contaminants in lake trout eggs are above the threshold for hemorrhaging and yolk-sac edema. The results also support the use of an additive model of toxicity to quantify PCDDs, PCDFs, Non-o-PCBs, and Mono-o-PCBs in relation to early life stage mortality in Lake Michigan lake trout.

  9. Stability of uncoated and fulvic acids coated manufactured CeO2 nanoparticles in various conditions: From ultrapure to natural Lake Geneva waters.

    PubMed

    Oriekhova, Olena; Stoll, Serge

    2016-08-15

    Understanding the behavior of engineered nanoparticles in natural water and impact of water composition in changing conditions is of high importance to predict their fate once released into the environment. In this study we investigated the stability of uncoated and Suwannee River fulvic acids coated CeO2 manufactured nanoparticles in various environmental conditions. The effect of pH changes on the nanoparticle and coating stability was first studied in ultrapure water as well as the variation of zeta potentials and sizes with time in presence of fulvic acids at environmental pH. Then the stability of CeO2 in synthetic and natural Lake Geneva waters was investigated as a function of fulvic acids concentration. Our results indicate that the adsorption of environmentally relevant concentrations of Suwannee River fulvic acids promotes CeO2 stabilization in ultrapure water as well as synthetic water and that the coating stability is high upon pH variations. On the other hand in natural Lake Geneva water CeO2 NPs are found in all cases aggregated due to the effect of heterogeneous organic and inorganic compounds.

  10. 21 CFR 582.4521 - Monosodium phosphate derivatives of mono- and diglycerides of edible fats or oils, or edible fat...

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... diglycerides of edible fats or oils, or edible fat-forming fatty acids. 582.4521 Section 582.4521 Food and... fatty acids. (a) Product. Monosodium phosphate derivatives of mono- and diglycerides of edible fats or oils, or edible fat-forming fatty acids. (b) Conditions of use. This substance is generally...

  11. Characterization of year-round sensitivity of California's Montane Lakes to acidic deposition. Final report, October 1986-June 1989

    SciTech Connect

    Sickman, J.O.; Melack, J.M.

    1989-06-01

    Four high-elevation, lake watersheds in the Sierra Nevada were studied from October 1986 through June 1988. Researchers measured wet deposition, lake outflow and lake chemistry and physics at these sites using the mass-balance approach to relate the effect of wet deposition on lake and stream water chemistry. Crystal and Ruby Lakes, located on the eastern slope of the Sierra, and Topaz and Pear Lakes, located on the western slope in Sequoia National Park, were found to be dimictic. Major solute concentrations in the subsurface reached a minima during the latter part of snowmelt. Near-bottom concentrations of these solutes generally had less seasonal variation and were generally higher than subsurface values. Mean snow depth and chemical concentrations were similar for the winters of 1986-87 and 1987-88 at all watersheds. Volume-weighted mean pH ranged from 5.3 to 5.5, with the dominant ion being hydrogen, ammonium, acetate, nitrate and sulfate. Wet deposition as mixed rain and snow occurring between May and October can deliver more solutes to the watersheds than winter snows.

  12. Retrieval of lake water temperature based on LandSat TM imagery: A case study in East Lake of Wuhan

    NASA Astrophysics Data System (ADS)

    Cao, Bo; Kang, Ling; Yang, Shengmei

    2013-10-01

    Lake water temperature is one of the most important parameters determining ecological conditions in lake water. With the recent development of satellite remote sensing, remotely sensed data instead of traditional sampling measurement can be used to retrieve the lake surface temperature. The East Lake located in the Wuhan city was selected as research region in this paper. The mono window algorithm has been applied to retrieve the lake water temperature of East lake basin with Landsat TM data. Through three groups of field survey data, the outcome shows that the retrieval results using the mono window model are quite approximate to the same period of the experimental region historical temperature data. So, it is feasible to utilize the remote sensing method to obtain the lake temperature. Meanwhile, the retrieval results also demonstrate that the East Lake surface temperatures from different years have the similar distribution regularity. Generally speaking, the temperature of the lake center is higher than the surrounding area. The west of lake is mostly higher than the east mainly due to the vegetation density and urbanization distribution condition. This conclusion is important to the further study on monitoring the East Lake temperature particularly in large scale.

  13. Identification of 8-O-4/8-5(Cyclic)- and 8-8(Cyclic)/5-5-Coupled Dehydrotriferulic Acids, Naturally Occurring in Cell Walls of Mono- and Dicotyledonous Plants.

    PubMed

    Waterstraat, Martin; Bunzel, Diana; Bunzel, Mirko

    2016-09-28

    Besides ferulate dimers, higher oligomers of ferulic acid such as trimers and tetramers were previously demonstrated to occur in plant cell walls. This paper reports the identification of two new triferulic acids. 8-O-4/8-5(cyclic)-triferulic acid was synthesized from ethyl ferulate under oxidative conditions using copper(II)-tetramethylethylenediamine [CuCl(OH)-TMEDA] as a catalyst, whereas 8-8(cyclic)/5-5-triferulic acid was isolated (preparative size exclusion chromatography, reversed-phase HPLC) from saponified insoluble maize fiber. Structures of both trimers were unambiguously elucidated by high-resolution LC-ToF-MS/MS and one- ((1)H) and two-dimensional (HSQC, HMBC, COSY, NOESY) NMR spectroscopy. The newly described trimers were identified by LC-MS/MS in alkaline hydrolysates of insoluble fibers from maize, wheat, and sugar beet, indicating that ferulic acid cross-links between cell wall polymers are more diverse than previously recognized. Saponification experiments also suggest that the newly identified 8-O-4/8-5(cyclic)-triferulic acid is the naturally occurring precursor of the previously identified 8-O-4/8-5(noncyclic)-triferulic acid in plant cell walls.

  14. Extracting the complex optical conductivity of mono- and bilayer graphene by ellipsometry

    NASA Astrophysics Data System (ADS)

    Chang, You-Chia; Liu, Chang-Hua; Liu, Che-Hung; Zhong, Zhaohui; Norris, Theodore B.

    2014-06-01

    A method for analysis of spectroscopic ellipsometry data is demonstrated to extract the optical conductivity of mono- and bilayer chemical-vapor-deposited graphene. We model graphene as a truly two-dimensional (2D) material with a sheet conductivity, rather than a phenomenological effective refractive index as has been used in the literature. This technique measures both the real and imaginary part of the optical conductivity, which is important for graphene optoelectronics and metamaterials. Using this method, we obtain broadband measurements of the complex optical conductivity for mono- and bilayer graphene from ultraviolet to mid-infrared wavelengths. We also study how chemical doping with nitric acid modifies the complex optical conductivity.

  15. Sources of acid and metals from the weathering of the Dinero waste pile, Lake Fork watershed, Leadville, Colorado

    USGS Publications Warehouse

    Diehl, S.F.; Hageman, Phil L.; Smith, Kathleen S.; Herron, J.T.; Desborough, G.A.

    2005-01-01

    Two trenches were dug into the south Dinero mine-waste pile near Leadville, Colorado, to study the weathering of rock fragments and the mineralogic sources of metal contaminants in the surrounding wetland and Lake Fork Watershed. Water seeping from the base of the south Dinero waste-rock pile was pH 2.9, whereas leachate from a composite sample of the rock waste was pH 3.3. The waste pile was mostly devoid of vegetation, open to infiltration of precipitation, and saturated at the base because of placement in the wetland. The south mine-waste pile is composed of poorly sorted material, ranging from boulder-size to fine-grained rock fragments. The trenches showed both matrix-supported and clast-supported zones, with faint horizontal color banding, suggesting zonation of Fe oxides. Secondary minerals such as jarosite and gypsum occurred throughout the depth of the trenches. Infiltration of water and transport of dissolved material through the pile is evidenced by optically continuous secondary mineral deposits that fill or line voids. Iron-sulfate material exhibits microlaminations with shrinkage cracking and preferential dissolution of microlayers that evidence drying and wetting events. In addition to fluids, submicron-sized to very fine-grained particles such as jarosite are transported through channel ways in the pile. Rock fragments are coated with a mixture of clay, jarosite, and manganese oxides. Dissolution of minerals is a primary source of metals. Skeletal remnants of grains, outlined by Fe-oxide minerals, are common. Potassium jarosite is the most abundant jarosite phase, but Pb-and Ag-bearing jarosite are common. Grain-sized clusters of jarosite suggest that entire sulfide grains were replaced by very fine-grained jarosite crystals. The waste piles were removed from the wetland and reclaimed upslope in 2003. This was an opportunity to test methods to identify sources of acid and metals and metal transport processes within a waste pile. A series of

  16. Lake Life.

    ERIC Educational Resources Information Center

    Ohrn, Deborah Gore, Ed.

    1993-01-01

    This quarterly publication of the State Historical Society of Iowa features articles and activities for elementary school students. This summer issue focuses on the topic of lake life. The issue includes the following features: (1) "Where the Lakes Are Map"; (2) "Letter from the Lake"; (3) "Lake People"; (4)…

  17. MAGNESIUM MONO POTASSIUM PHOSPHATE GROUT FOR P-REACTOR VESSEL IN-SITU DECOMISSIONING

    SciTech Connect

    Langton, C.; Stefanko, D.

    2011-01-05

    The objective of this report is to document laboratory testing of magnesium mono potassium phosphate grouts for P-Reactor vessel in-situ decommissioning. Magnesium mono potassium phosphate cement-based grout was identified as candidate material for filling (physically stabilizing) the 105-P Reactor vessel (RV) because it is less alkaline than portland cement-based grout (pH of about 12.4). A less alkaline material ({<=} 10.5) was desired to address a potential materials compatibility issue caused by corrosion of aluminum metal in highly alkaline environments such as that encountered in portland cement grouts. Information concerning access points into the P-Reactor vessel and amount of aluminum metal in the vessel is provided elsewhere. Fresh and cured properties were measured for: (1) commercially blended magnesium mono potassium phosphate packaged grouts, (2) commercially available binders blended with inert fillers at SRNL, (3) grouts prepared from technical grade MgO and KH{sub 2}PO{sub 4} and inert fillers (quartz sands, Class F fly ash), and (4) Ceramicrete{reg_sign} magnesium mono potassium phosphate-based grouts prepared at Argonne National Laboratory. Boric acid was evaluated as a set retarder in the magnesium mono potassium phosphate mixes.

  18. EPA Directs DuPont to Remove Mercury from Pompton Lake in Pompton Lakes, New Jersey

    EPA Pesticide Factsheets

    (New York, N.Y.) The U.S. Environmental Protection Agency today released its final plan to remove mercury contamination from areas of Pompton Lake in Pompton Lakes, New Jersey, including the areas where the Acid Brook flows into the lake, called the Acid B

  19. New insights into the biogeochemistry of extremely acidic environments revealed by a combined cultivation-based and culture-independent study of two stratified pit lakes.

    PubMed

    Falagán, Carmen; Sánchez-España, Javier; Johnson, David Barrie

    2014-01-01

    The indigenous microbial communities of two extremely acidic, metal-rich stratified pit lakes, located in the Iberian Pyrite Belt (Spain), were identified, and their roles in mediating transformations of carbon, iron, and sulfur were confirmed. A combined cultivation-based and culture-independent approach was used to elucidate microbial communities at different depths and to examine the physiologies of isolates, which included representatives of at least one novel genus and several species of acidophilic Bacteria. Phosphate availability correlated with redox transformations of iron, and this (rather than solar radiation) dictated where primary production was concentrated. Carbon fixed and released as organic compounds by acidophilic phototrophs acted as electron donors for acidophilic heterotrophic prokaryotes, many of which catalyzed the dissimilatory reduction in ferric iron; the ferrous iron generated was re-oxidized by chemolithotrophic acidophiles. Bacteria that catalyze redox transformations of sulfur were also identified, although these Bacteria appeared to be less abundant than the iron oxidizers/reducers. Primary production and microbial numbers were greatest, and biogeochemical transformation of carbon, iron, and sulfur, most intense, within a zone of c. 8-10 m depth, close to the chemocline, in both pit lakes. Archaea detected in sediments included two Thaumarchaeota clones, indicating that members of this recently described phylum can inhabit extremely acidic environments.

  20. Influence of in ovo mercury exposure, lake acidity, and other factors on common loon egg and chick quality in Wisconsin

    EPA Science Inventory

    We conducted a field study in Wisconsin to characterize in ovo mercury (Hg) exposure in common loons (Gavia immer). Total Hg mass fractions ranged from 0.17 to 1.23 ìg/g wet weight (ww) in eggs collected from nests on lakes representing a wide range of pH (5.0 - 8.1) and ...

  1. Episodic acidification of Adirondack lakes during snowmelt

    SciTech Connect

    Schaefer, D.A.; Driscoll, C.T.; Van Dreason, R.; Yatsko, C.P.

    1990-07-01

    Maximum values of acid neutralizing capacity (ANC) in Adirondack, New York lake outlets generally occur during summer and autumn. During spring snowmelt, transport of acidic water through acid-sensitive watersheds causes depression of upper lake water ANC. In some systems lake outlet ANC reaches negative values. The authors examined outlet water chemistry from II Adirondack lakes during 1986 and 1987 snowmelts. In these lakes, SO concentrations were diluted during snowmelt and did not depress ANC. For lakes with high baseline ANC values, springtime ANC depressions were primarily accompanied by basic cation dilution. For lakes with low baseline ANC, No increases dominated ANC depressions. Lakes with intermediate baseline ANC were affected by both processes and exhibited larger ANC depressions. Ammonium dilution only affected wetland systems. A model predicting a linear relationship between outlet water ANC minima and autumn ANC was inappropriate. To assess watershed response to episodic acidification, hydrologic flow paths must be considered. (Copyright (c) 1990 by the American Geophysical Union.)

  2. Production of levulinic acid, furfural, and gamma valerolactone from C.sub.5 and C.sub.6 carbohydrates in mono- and biphasic systems using gamma-valerolactone as a solvent

    DOEpatents

    Dumesic, James A.; Alonso, David Martin; Gurbuz, Elif I.; Wettstein, Stephanie G.

    2013-03-19

    A method to make levulinic acid (LA), furfural, or gamma-valerolactone (GVL). React cellulose (and/or other C.sub.6 carbohydrates) or xylose (and/or other C.sub.5 carbohydrates) or combinations thereof in a monophasic reaction medium comprising GVL and an acid; or (ii) a biphasic reaction system comprising an organic layer comprising GVL, and a substantially immiscible aqueous layer. At least a portion of the cellulose (and/or other C.sub.6 carbohydrates), if present, is converted to LA and at least a portion of the xylose (and/or other C.sub.5 carbohydrates), if present, is converted into furfural.

  3. Geochemistry of sediments in cores and sediment traps from Bear Lake, Utah and Idaho

    USGS Publications Warehouse

    Bischoff, James L.; Cummins, Kathleen; Shamp, Donald D.

    2005-01-01

    The present study of Bear Lake began in 1998. Initially, the study utilized sediments from three long cores (up to 5 m) previously collected in 1996 and short cores (up to 40 cm) collected in 1998. The short cores were specifically acquired to preserve the uppermost layers of sediment that may have been lost in the long cores. In addition, three arrays of sediment traps were deployed during the summer of 1998, and sediment from these traps was collected during the summers of 1999 and 2000 (see Dean and others, 2005, for core and sediment trap locations). The cores and sediment traps were sampled, and splits were distributed to various investigators for analyses of a wide variety of sediment parameters. The chemical composition of the acid-soluble component of the sediments is presented in this report. HCl or HNO3 treatment of the sediment quantitatively dissolves the authigenic component of the sediment, a component that includes carbonates, sulfates, and iron-mono sulfides. In the case of Bear Lake, CaCO3 is the major component of the sediment today and for most of the Holocene (Dean and others 2005). The chemical composition of the acid-soluble fraction gives important information on this component and, therefore, insight into the chemical conditions of the lake at the time of carbonate deposition.

  4. Microcalorimetric determination of the thermodynamics of formation of the mono- and bi-sulfato complexes of lanthanum in aqueous solutions between 25 and 55 degrees C

    SciTech Connect

    Simpson, C.; Matijevic, E.

    1987-05-01

    Using a differential microcalorimeter, the formation constants and enthalpies of formation of the mono- and bi-sulfato complexes of lanthanum ion have been evaluated for aqueous acidic solutions over a temperature range of 25 to 55/sup 0/C.

  5. Investigations on the "Extreme" Microbial Arsenic Cycle within the Sediments of an Acidic Impoundment of the Former Sulfur Bank Mercury Mine: Herman Pit, Clear Lake, California.

    NASA Astrophysics Data System (ADS)

    Blum, J. S.; Hoeft McCann, S. E.; Bennett, S.; Miller, L. G.; Stoneburner, B.; Saltikov, C.; Oremland, R. S.

    2014-12-01

    The involvement of prokaryotes in the redox reactions of arsenic occurring between this element's +5 [arsenate; As(V)] and + 3 [arsenite; As(III)] oxidation states has been well established. Most research has focused upon circum-neutral pH environments, such as freshwater lake and aquifer sediments, and extreme environments like hot springs and hypersaline soda lakes have also been well investigated. In contrast, little work has been conducted on acidic environments. The azure-hued, clear waters of the Herman Pit are acidic (pH 2-4), and overlie oxidized sediments that have a distinctive red/orange coloration indicative of the presence of ferrihydrites and other Fe(III) minerals. There is extensive ebullitive release of geothermal gases from the lake bottom in the form of numerous continuous-flow seeps which are composed primarily of mixtures of CO2, CH4, and H2S. We collected near-shore surface sediments with an Eckman grab, and stored the "soupy" material in filled mason jars kept at 4˚C. Initial experiments were conducted using 3:1 mixtures of lake water: sediment so as to generate dilute slurries which were amended with mM levels of electron acceptors (arsenate, nitrate, oxygen), electron donors (arsenite, acetate, lactate, hydrogen), and incubated under N2, air, or H2. Owing to the large adsorptive capacity of the Fe(III)-rich slurries, we were unable to detect As(V) or As(III) in the aqueous phase of either live or autoclaved controls, although the former consumed lactate, acetate, nitrate, or hydrogen, while the latter did not. This prompted us to conduct a series of further diluted slurry experiments using the live materials from the first as a 10 % addition to lakewater. In these experiments we observed reduction of As(V) to As(III) in anoxic slurries and that rates were enhanced by addition of electron donors (H2, acetate, or lactate). We also observed oxidation of As(III) to As(V) in oxic slurries and in anoxic slurries amended with nitrate. These

  6. Water resources data for California, water year 1993. Volume 1. Southern Great Basin from Mexican border to Mono Lake Basin, and Pacific Slope Basins from Tijuana River to Santa Maria River. Water-data report (Annual), 1 October 1992-30 September 1993

    SciTech Connect

    Mullen, J.R.; Hayes, P.D.; Agajanian, J.A.

    1994-06-01

    Water resources data for the 1993 water year for California consist of records of stage, discharge, and water quality of streams; stage and contents in lakes and reservoirs; and water levels and water quality in wells. Volume 1 contains (1) discharge records for 156 streamflow-gaging stations, 12 crest-stage partial-record streamflow stations, and 5 miscellaneous measurement stations; (2) stage and contents records for 26 lakes and reservoirs; (3) water-quality records for 17 streamflow-gaging stations and 6 partial-record stations; and (4) precipitation records for 10 stations.