Sample records for mono lake suggests

  1. Mono Lake Excursion Reviewed

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


    The Mono Lake Excursion as recorded in the Mono Basin, CA, has an older part that is about negative 30 degrees inclination and about 300 degrees declination during low relative field intensity. Those paleomagnetic directions are closely followed by greater than 80 degrees positive inclination and east declination of about 100 degrees during higher relative field intensity. A path of the Virtual Geomagnetic Poles (VGPs) for the older part followed from old to young forms a large clockwise loop that reaches 35 degrees N latitude and is centered at about 35 degrees E longitude. That loop is followed by a smaller one that is counterclockwise and centered at about 70 degrees N latitude and 270 degrees E longitude (Denham & Cox, 1971; Denham, 1974; Liddicoat & Coe, 1979). The Mono Lake Excursion outside the Mono Basin in western North America is recorded as nearly the full excursion at Summer Lake, OR (Negrini et al., 1984), and as the younger portion of steep positive inclination/east declination in the Lahontan Basin, NV. The overall relative field intensity during the Mono Lake Excursion in the Lahontan Basin mirrors very closely the relative field intensity in the Mono Basin (Liddicoat, 1992, 1996; Coe & Liddicoat, 1994). Using 14C and 40Ar/39Ar dates (Kent et al., 2002) and paleoclimate and relative paleointensity records (Zimmerman et al., 2006) for the Mono Lake Excursion in the Mono Basin, it has been proposed that the Mono Lake Excursion might be older than originally believed and instead be the Laschamp Excursion at about 40,000 yrs B.P. (Guillou et al., 2004). On the contrary, we favor a younger age for the Mono Lake Excursion, about 32,000 yrs B.P., using the relative paleointensity in the Mono Basin and Lahontan Basin and 14C dates from the Lahontan Basin (Benson et al., 2002). The age of about 32,000 yrs B.P. is also in accord with the age (32,000- 34,000 yrs B.P.) reported by Channell (2006) for the Mono Lake Excursion at ODP Site 919 in the Irminger Basin

  2. Mafic replenishment of multiple felsic reservoirs at the Mono domes and Mono Lake islands, California

    Bray, Brandon; Stix, John; Cousens, Brian


    The Mono Basin has been the site of frequent volcanic activity over the past 60,000 years, including the emplacement of the Mono domes and Mono Lake islands. The Mono Basin lavas are the youngest and most poorly understood products of the Long Valley Volcanic Field. We have undertaken a study of Mono Basin volcanism encompassing whole-rock major and trace element, Sr, Nd, Pb, and O isotopic, and electron microprobe glass, plagioclase, and amphibole analyses. Variations in major and trace elements suggest that fractional crystallization of feldspar (Sr, K2O), apatite (P2O5), titanomagnetite (V), zircon (Zr), and allanite (La, Ce) has influenced the evolution of the Mono Basin lavas. Field observations, petrography, and chemistry together demonstrate that injection of more mafic magma is a common process throughout the Mono Basin. Mafic enclaves of the Mono domes are stretched and rounded, with chilled margins between enclave and host rhyolite. Thin sections reveal millimeter-scale inclusions of rhyolite in the enclaves and vice versa along the host-enclave border. Paoha Island dacite has glass with 67-72 wt% SiO2 and contains microscopic clots of more mafic glasses, with SiO2 contents as low as 64 wt%. Isotopically, the June Lake and Black Point basalts and the Mono dome enclaves represent the least evolved material in the Long Valley Volcanic Field, with 87Sr/86Sri 0.5126. The silicic Mono Lake lavas and Mono dome rhyolites display a significant crustal component, with 87Sr/86Sri >0.7058 and 143Nd/144Nd 19 and δ18O >+6.5‰. The Mono Lake lavas generally are younger and less evolved than the Mono domes, with enrichment in trace elements including Ba and Sr accompanied by lower 143Nd/144Nd and higher 206Pb/204Pb. This implies that the Mono domes and the Mono Lake lavas are derived from different magma batches, if not from separate magma chambers. There is no systematic relationship between the degree of chemical evolution and the lava ages, indicating that several

  3. Crustal structure between Lake Mead, Nevada, and Mono Lake, California

    Johnson, Lane R.


    Interpretation of a reversed seismic-refraction profile between Lake Mead, Nevada, and Mono Lake, California, indicates velocities of 6.15 km/sec for the upper layer of the crust, 7.10 km/sec for an intermediate layer, and 7.80 km/sec for the uppermost mantle. Phases interpreted to be reflections from the top of the intermediate layer and the Mohorovicic discontinuity were used with the refraction data to calculate depths. The depth to the Moho increases from about 30 km near Lake Mead to about 40 km near Mono Lake. Variations in arrival times provide evidence for fairly sharp flexures in the Moho. Offsets in the Moho of 4 km at one point and 2 1/2 km at another correspond to large faults at the surface, and it is suggested that fracture zones in the upper crust may displace the Moho and extend into the upper mantle. The phase P appears to be an extension of the reflection from the top of the intermediate layer beyond the critical angle. Bouguer gravity, computed for the seismic model of the crust, is in good agreement with the measured Bouguer gravity. Thus a model of the crustal structure is presented which is consistent with three semi-independent sources of geophysical data: seismic-refraction, seismic-reflection, and gravity.

  4. Was Mono Lake a 14C dump?

    Maggs, William Ward

    This is a scientific story without an explanation, called a “mystery” and an “enigma” in articles by the people who discovered it. Confounded by evidence they cannot explain by natural processes, these scientists implicate human beings.One month ago in Eos, (June 7, 1988, p. 633), Wallace Broecker and Scott Stine reported abnormally high levels of radiogenic 14C in California's Mono Lake, now a National Historic Site. The only logical explanation, they proposed, is that someone secretly dumped a total of about 20 curies of 14C into the lake in two doses, sometime between 1952 and 1958 and again between 1966 and 1977. Broecker and Stine, geologists at Lamont-Doherty Geological Observatory in Palisades, N.Y., called on readers for information on the source of the 14C.

  5. Mono Lake Analog Mars Sample Return Expedition for AMASE

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


    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.

  6. Review of the recording and age of the Mono Lake Excursion

    Coe, R.; Liddicoat, J.


    Among the brief departures from gradual, long-term behaviour of the palaeomagnetic field in the Brunhes Normal Chron that reached opposite polarity or have a Virtual Geomagnetic Pole deep in the southern hemisphere, the first to be reported is the Laschamp Excursion (LE) in volcanic rocks in the Massif Central in France (Bonhommet and Zahringer, 1969). They originally believed it occurred between about 9,000 to 20,000 years before present, but it is now assigned an age of about 40,000 years B.P. (Guillou et al., 2004). Denham and Cox (1971) unsuccessfully sought the LE in exposed lake sediments that seemed to span that interval in the Mono Basin in the western Great Basin of the U.S., but instead encountered anomalous field behaviour that is called the Mono Lake Excursion (MLE)(Liddicoat and Coe, 1979). As a tribute to Norbert Bonhommet, who assisted us in our initial field work in the Mono Basin and shared a long-standing interest in the LE and MLE, we will review the palaeomagnetic behaviour and age of the MLE in the Mono Basin and elsewhere, for which there are nearly 20 reports of its occurrence globally, and evaluate the recent suggestion that the excursion at Mono Lake and the LE are the same.

  7. Age of the Mono Lake excursion and associated tephra

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


    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).

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

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


    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.

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

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


    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.

  10. A New 62-sample Record of the Mono Lake Excursion Waveform from the Depocenter Sediments of Summer Lake, OR

    Negrini, R. M.; McCuan, D. T.; Horton, R. A.; Verosub, K. L.


    A new core from Summer Lake, Oregon provides the primary datset for a composite, 62-sample record of the Mono Lake Excursion (MLE) waveform. The magnetograms and virtual geomagnetic poles (VGPs) are consistent with those associated with the MLE record from Mono Lake (e.g., Liddicoat and Coe, 1979). The added detail from this new record firmly establishes three distinct VGP clusters centered first on easternmost Asia/Siberia, then on Europe, and, finally, on North America. The jumps between clusters involve typically one sample, which represents only a few decades of time. The excursion is bracketed by tephra of known age (the Mount St. Helens Cy 46.0 ± 6 ka and the Wono 27.3 ± 0.3 14C kyr B.P.) and the age of the excursion is ~28 14C kyr B.P based on an average of five radiocarbon ages from below, within and above the excursion interval. A second waveform that exhibits shallowing inclinations and easterly declination swings upsection is truncated by a prominent unconformity. These PSV features and the associated RPI leading up to this unconformity correlate with those of the onset of the Laschamp Excursion (Lund et al., 2005). Both radiocarbon and PSV correlations support missing sediment from the Summer Lake record between 42.5 and 38 GISP2 ka. This sediment hiatus correlates to unconformities or lowstands in other Great Basin lakes suggesting a Heinrich 4-induced drought that affected much of western North America.

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

    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.


    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.

  12. Possible recording of the Mono Lake Excursion in cored sediment from Clear Lake, California

    Liddicoat, Joseph; Verosub, Kenneth


    We report the possible recording of the Mono Lake Excursion (MLE) in cored sediment from Clear Lake, CA. The locality (39.0˚N, 237.3˚E) is about 120 km north of San Francisco, CA, and 320 km northwest of the Mono Basin, CA, where the MLE first was discovered in North America (Denham and Cox, 1971). The field behaviour at Clear Lake that might be the MLE is recorded in clay and peaty clay about 50 cm below the top of the lowermost 80-cm core slug of a 21.6-m core. The coring was done by the wire-line method (Sims and Rymer, 1975) and the samples (rectangular solids 21 mm on a side and 15 mm high) were measured in a cryogenic magnetometer after demagnetization in an alternating field to 35 milliTesla (Verosub, 1977). The continuously-spaced samples record negative inclination of nearly 20˚ and northerly declination when unnormalized relative field intensity was reduced by an order of magnitude from the mean value. Those palaeomagnetic directions are followed immediately by positive inclination to about 50˚ and easterly declination of about 60˚ when the field intensity is at a relative high. That pattern of behaviour is recorded at three localities (Wilson Creek, Mill Creek, and Warm Springs) in the Mono Basin at the MLE (Liddicoat and Coe, 1979; Liddicoat, 1992). A path of the Virtual Geomagnetic Poles (VGPs) at Clear Lake form a clockwise-trending loop that is centered at 65˚N, 20˚E in the hemisphere away from the locality. The VGP that is farthest from the North Geographic Pole is at 29.3˚N, 337.1˚E, which is close to the path formed by the VGPs in the older portion of the MLE (Liddicoat and Coe, 1979; Liddicoat, 1992). The age of the sediment recording the anomalous palaeomagnetic directions in Clear Lake is about 30,000 years B.P. (Verosub, 1977). That age was determined from six (uncalibrated) radiocarbon dates, three of which are from near the base of the core (Sims and Rymer, 1975) where there are the anomalous palaeomagnetic directions, and linear

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

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


    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

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

    Gill, Thomas Edward


    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

  15. High resolution seismic reflection profiles of Holocene volcanic and tectonic features, Mono Lake, California

    Jayko, A. S.; Hart, P. E.; Bursik, M. I.; McClain, J. S.; Moore, J. C.; Boyle, M.; Childs, J. R.; Novick, M.; Hill, D. P.; Mangan, M.; Roeske, S.


    The Inyo-Mono Craters of Long Valley and Mono Basin, California are the youngest eruptive vents of the Great Basin, USA and the second youngest in California. They are one of two seismically active volcanic centers with geothermal power production in the Walker Lane, western Great Basin, the other being the Coso Volcanic Field to the south. High resolution seismic reflection data collected from the northern tip of the Mono Craters eruptive centers in Mono Lake delinates two structural zones proximal to the active volcanic centers in Mono Lake. A growth structure drapped by ~30 m or more of bedded sediment shows increasing deformation and offset of clastic deposits on the northwest margin of the basin. Coherent thin-bedded stratigraphic sections with strong reflectors to 30-100m depth are preserved on the western and northern margins of the basin. The southern and southeastern areas of the lake are generally seismically opaque, due to extensive ash and tephra deposits as well as widespread methane. Thin pockets of well-bedded, poorly consolidated sediment of probable Holocene and last glacial age are present within intrabasin depressions providing some local age constraints on surfaces adjacent to volcanic vents and volcanically modified features.

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

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


    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.

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

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


    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.

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

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


    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.

  19. Paleomagnetic Excursion Recorded in Exposed Lacustrine Sediments on Paoha Island in Mono Lake, CA.

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


    Paleomagnetic secular variation (PSV) in the Wilson Creek Formation that was deposited in Pleistocene Lake Russell in the Mono Basin, CA, has been known for nearly 50 years. The research began in the late 1960s during a search for the Laschamp Excursion (LE) believed then to have occurred between about 20,000 and 9,000 years ago (Bonhommet and Zahringer, 1969). Although that investigation was unsuccessful in locating the LE in the eroded bank of Wilson Creek on the northwest side of Mono Lake, which is the remnant of Lake Russell, anomalous field behavior was documented that is the Mono Lake Excursion (MLE)(Denham and Cox, 1971; Liddicoat and Coe, 1979). We did a PSV investigation of a portion of the Wilson Creek Formation where it is exposed on Paoha Island in the center of Mono Lake. Using volcanic ash layers from the nearby Mono Craters as stratigraphc marker beds and the tephrochronology of Lajoie (1993), we located anomalous field behavior that is similar to the field behavior during the MLE with some exceptions. One is the onset of negative inclination 45 cm beneath a 7-cm rhyolitic ash bed. That position is four times lower in the formation than negative inclination beneath Ash 15 that is midway in the MLE at three localities in the basin - Wilson Creek, Mill Creek, and Warm Springs (Liddicoat, 1992). Declination, inclination, and relative field intensity (RFI) where we sampled on Paoha Island are different enough from the paleomagnetic field behavior during the MLE that the possibility exists that a second excursion is recorded in the Wilson Creek Formation. We will present the paleomagnetic directions and RFI that are recorded on Paoha Island for that field behavior.

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

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


    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

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

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


    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

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

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


    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.

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

    Ciulla, R.A.; Roberts, M.F. [Boston College, Chestnut Hill, MA (United States); Diaz, M.R.; Taylor, B.F. [Univ. of Miami, FL (United States)


    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.

  4. Exploration Of Mono Lake With An ROV: a prototype experiment for the MAPS AUV program

    Stoker, C. R.; Barch, D.; Farmer, J.; Flagg, M.; Healy, T.; Tengdin, T.; Thomas, H.; Schwer, K.; Stakes, D.


    This paper describes a field experiment to explore Mono Lake using the Telepresence Controlled Remotely Operated Vehicle (TROV). This experiment was a prototype study demonstrating the science capabilities defined for a new AUV planned for development by a consortium project called MAPS. The goal of the experiment was to study mineralization processes associated with thermal and non-thermal spring inflow into Mono Lake, a hypersaline, alkaline lake in eastern California located in a volcanically active area. TROV is a tethered ROV, which can be controlled using a virtual reality-based user interface. TROV's video capabilities included a matched pair of stereo video cameras on a rapid pan and tilt platform and a single fixed downward pointing camera. Additional capabilities included high resolution 750 kHz pencil beam SONAR and 1 MHz scanning SONAR for navigating in the murky water, instruments for measuring water column properties (C,T,D, pH), a syringe water sample, and a three function manipulator arm used to collect mineral samples and place them in a sample box mounted on the vehicle. TROV was navigated using a DiveTracker acoustic navigation system. TROV was deployed from the deck of a houseboat anchored above the field sites with control and data recording equipment also onboard. The boat's location was continuously recorded using differential GPS system during 10 days of field operations. TROV had a total of 38 hours of bottom time. We studied 4 sites including (1) a broad, gently sloping, ooze-covered mound SE of Paoha island with copious methane gas seeps, (2) shallow, tufa-coated pinnacles of volcanic origin associated with islets NE of Paoha Island, (3) subaqueous thermal springs located along the SE shore of Paoha Island, and (4) a deep area (~50m) E of Paoha Island.

  5. A Eukaryotic green alga, Picocystis, dominates Mono Lake, California in an algal bloom - Hints at cryptic oxygen cycle in euxinic waters

    Tookmanian, E. M.; Bauer, K. W.; Thompson, K.; Waldeck, A.; Berelson, W.; Stevenson, B. S.; Stamps, B. W.; Johnson, H.; Sessions, A. L.; Miller, L. G.; Oremland, R. S.; Rosen, M. R.; Corsetti, F. A.; Spear, J. R.


    Mono Lake is a closed-basin stratified soda lake (pH = 9.8; salinity = 60 g/L) that supports high rates of primary productivity (annual average of 100 mmol C m-2 d-1), and is dominated by a eukaryotic alga, Picocystis strain ML. To further investigate the unique biology of the lake, we sampled the water column during an algal bloom when productivity was on the order of 1500 mmol C m-2 d-1 at 2 m depth. Picocystis was abundant at all depths in SSU rRNA gene sequencing libraries. Interestingly, the relative abundance of Picocystis was greatest at 20 m depth. This part of the water column was well below the oxycline (12 m) and detectable photosynthetically active radiation (5 m). Sulfide concentrations from previous work increased just below 20 m to millimolar concentrations; however, analysis of metatranscriptomic data indicated that genes involved in both photosystem I and II were expressed at 25 m. This suggests that photosynthesis was active despite euxinic waters and light conditions below our detectable limit. Metagenomes and metatranscriptomes at 20 and 25 m depth also revealed an abundance of sulfide oxidizing genes (soxA and soxB). These metabolisms are often mixotrophic, using oxygen as their electron acceptor, presenting further support for photosynthetic oxygen production at depth. We suggest that Picocystis may be producing oxygen through photosynthesis in the euxinic bottom waters of Mono Lake. The oxygen produced would be extremely transient, consumed in either abiotic or microbially-mediated oxidation of sulfide, or both. This potential cryptic oxygen cycle in the euxinic bottom waters of Mono Lake could explain the fate of large sulfide fluxes from sediments, as well as offer an opportunity to explore the biogeochemistry of this site to inform how we approach the rise of oxygen and early evolution of life.

  6. Identification and dating of the Mono Lake excursion in lava flows from the Canary islands.

    Guillou, Hervé; Laj, Carlo; Carracedo, Juan-Carlos; Kissel, Catherine; Nomade, Sebastien; Perez-Torrado, Francisco; Wandres, Camille


    The Mono Lake geomagnetic excursion was defined from the study of lacustrine sections from Western North America [Denham, 1974; Liddicoat et al., 1979]. The proposed age for this excursion reported in the literature changed in time since the first observation and a debate was even very recently opened about the reliability of the dating at the original section at Wilson Creek. In ice cores, a peak in the production of cosmogenic isotopes is clearly observed about 7 ka after the peak associated to the Laschamp excursion. This younger peak, attributed to the Mono Lake occurs between the millennial climatic cycles 7 and 6 (Dansgaard-Oeschger cycles), around 34 kyr in the most recent Greenland ice age model. In addition, in other places, this excursion is described by an intensity low with only very rarely an associated directional shift, questioning the global character of this excursion. We present a coupled paleomagnetic and dating investigation conducted on four different lavas from the island of Tenerife (Spain) on the basis of preliminary K/Ar dating. From a paleomagnetic point of view, one of these sites is characterized by a direction largely deviated from the one calculated on the basis of an axial geocentric dipole field. The paleointensity values, determined using Thellier and Thellier method and the PICRIT03 set of criteria, is very low, about 8 µT. Two other sites are slightly deviated from the GAD value, in particular with lower inclinations. Paleointensity determinations from these lavas do not yet have a statistical significance and need to be completed but the first results indicate a value around 20 µT. Finally, the last site has a direction consistent with the GAD values and no reliable paleointensity determinations could be obtained so far. The preliminary K/Ar dating are now completed by Ar/Ar dating and their combination yield an average age of about 32 ka ± 2 ka for the four outcrops, not statistically distinguishable one from another. This

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

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


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

    Valet, Jean-Pierre; Valladas, Hélène


    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.

  9. 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

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


    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).

  10. Dating Lake Tahoe (CA/NV) and Mono Lake (CA) sediment using palaeomagnetic secular variation as a chronology for late Pleistocene palaeoclimate in the U.S. Great Basin

    Liddicoat, Joseph


    In 1976, six meters of graded and varved sediment were recovered in three piston cores from Lake Tahoe, CA/NV, and used for palaeomagnetic and sedimentologic investigations (Palmer et al., 1979; Denham, 1981). The long-term changes (secular variation) in the Lake Tahoe palaeomagnetic record were compared to secular variation in exposed lacustrine sediment of the Wilson Creek Formation (Lajoie, 1993) in the Mono Basin, CA, (Denham and Cox, 1971), 100 km away. During the more than 30 years since the coring was done in Lake Tahoe, the record of palaeomagnetic secular variation in the Mono Basin and elsewhere in the Great Basin has been refined (Liddicoat and Coe, 1979; Lund et al., 1988, Liddicoat and Coe, 1997; Liddicoat and Coe, 1998; Benson et al., 1998; Negrini and Davis, 1992; Kent et al., 2002; Zimmerman et al., 2006) to allow a reexamination of the palaeomagnetic directions and environmental magnetic record in the Lake Tahoe cores and the age of those sediments. Inferences are also possible about the sedimentological importance during the recording of the palaeomagnetic field at Lake Tahoe and possibly in the Mono Basin, and the age of the Lake Tahoe sediment recovered, which postdates the Mono Lake Excursion. The age of the Mono Lake Excursion and Wilson Creek Formation is relevant to investigations of Late Pleistocene palaeoclimate reconstructions for the U.S. Great Basin (Zimmerman et al., 2006).

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

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


    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

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

    Han, Ying; Liu, Wenbin; Hansen, Hans Chr. Bruun


    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...

  13. Phylogenies of microcystin-producing cyanobacteria in the lower Laurentian Great Lakes suggest extensive genetic connectivity.

    Timothy W Davis

    Full Text Available Lake St. Clair is the smallest lake in the Laurentian Great Lakes system. MODIS satellite imagery suggests that high algal biomass events have occurred annually along the southern shore during late summer. In this study, we evaluated these events and tested the hypothesis that summer bloom material derived from Lake St. Clair may enter Lake Erie via the Detroit River and represent an overlooked source of potentially toxic Microcystis biomass to the western basin of Lake Erie. We conducted a seasonally and spatially resolved study carried out in the summer of 2013. Our goals were to: 1 track the development of the 2013 summer south-east shore bloom 2 conduct a spatial survey to characterize the extent of toxicity, taxonomic diversity of the total phytoplankton population and the phylogenetic diversity of potential MC-producing cyanobacteria (Microcystis, Planktothrix and Anabaena during a high biomass event, and 3 compare the strains of potential MC-producers in Lake St. Clair with strains from Lake Erie and Lake Ontario. Our results demonstrated a clear predominance of cyanobacteria during a late August bloom event, primarily dominated by Microcystis, which we traced along the Lake St. Clair coastline downstream to the Detroit River's outflow at Lake Erie. Microcystin levels exceeded the Province of Ontario Drinking Water Quality Standard (1.5 µg L(-1 for safe drinking water at most sites, reaching up to five times this level in some areas. Microcystis was the predominant microcystin producer, and all toxic Microcystis strains found in Lake St. Clair were genetically similar to toxic Microcystis strains found in lakes Erie and Ontario. These findings suggest extensive genetic connectivity among the three systems.

  14. Historical profiles of PCB in dated sediment cores suggest recent lake contamination through the "halo effect".

    Naffrechoux, Emmanuel; Cottin, Nathalie; Pignol, Cécile; Arnaud, Fabien; Jenny, Jean-Philippe; Perga, Marie-Elodie


    We investigated the major sources of polychlorinated biphenyls (PCB) and interpreted the environmental fate processes of these persistent organic pollutants in the past and current PCB contamination of three large, urbanized, French peri-alpine lakes. Dated sediment cores were analyzed in order to reconstruct and compare the historical contamination in all three lakes. Stratigraphic changes of PCB contents and fluxes were considered as revealing the temporal dynamics of PCB deposition to the lakes and the distribution of the seven indicator congeners (further referred to as PCBi) as an indicator of the main contamination origin and pathway. Although located within a single PCB industrial production region, concentration profiles for the three lakes differed in timing, peak concentration magnitudes, and in the PCBi congeners compositions. PCBi fluxes to the sediment and the magnitude of the temporal changes were generally much lower in Lake Annecy (0.05-2 ng·cm(-2)·yr(-1)) as compared to Lakes Geneva (0.05-5 ng·cm(-2)·yr(-1)) and Bourget (5-290 ng·cm(-2)·yr(-1)). For all three lakes, the paramount contamination occurred in the early 1970s. In Lakes Annecy and Bourget, PCB fluxes have declined and plateaued at 0.5 and 8 ng·cm(-2)·yr(-1), respectively, since the early 1990s. In Lake Geneva, PCB fluxes have further decreased by the end of the XX(th) century and are now very low. For the most contaminated lake (Lake Bourget), the high PCBi flux (5-290 ng·cm(-2)·yr(-1)) and the predominance of heavy congeners for most of the time period are consistent with a huge local input to the lake. This still high rate of Lake Bourget is explained by transport of suspended solids from one of its affluents, polluted by an industrial point source. Intermediate historical levels and PCBi distribution over time for Lake Geneva suggest a mixed contamination (urban point sources and distant atmospheric transport), while atmospheric deposition to Lake Annecy explains its lowest

  15. What's Mono?

    ... es mono? Have you ever heard of the "kissing disease"? If you said that it's mono, you' ... But you don't get mono only from kissing. Infectious mononucleosis, called mono for short, is caused ...

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

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


    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).

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

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


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

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


    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).

  19. Arsenic(III) fuels anoxygenic photosynthesis in hot spring biofilms from Mono Lake, California

    Kulp, T.R.; Hoeft, S.E.; Asao, M.; Madigan, M.T.; Hollibaugh, J.T.; Fisher, J.C.; Stolz, J.F.; Culbertson, C.W.; Miller, L.G.; Oremland, R.S.


    Phylogenetic analysis indicates that microbial arsenic metabolism is ancient and probably extends back to the primordial Earth. In microbial biofilms growing on the rock surfaces of anoxic brine pools fed by hot springs containing arsenite and sulfide at high concentrations, we discovered light-dependent oxidation of arsenite [As(III)] to arsenate [As(V)] occurring under anoxic conditions. The communities were composed primarily of Ectothiorhodospira-like purple bacteria or Oscillatoria-like cyanobacteria. A pure culture of a photosynthetic bacterium grew as a photoautotroph when As(III) was used as the sole photosynthetic electron donor. The strain contained genes encoding a putative As(V) reductase but no detectable homologs of the As(III) oxidase genes of aerobic chemolithotrophs, suggesting a reverse functionality for the reductase. Production of As(V) by anoxygenic photosynthesis probably opened niches for primordial Earth's first As(V)-respiring prokaryotes.

  20. Antarctic lakes suggest millennial reorganizations of Southern Hemisphere atmospheric and oceanic circulation.

    Hall, Brenda L; Denton, George H; Fountain, Andrew G; Hendy, Chris H; Henderson, Gideon M


    The phasing of millennial-scale oscillations in Antarctica relative to those elsewhere in the world is important for discriminating among models for abrupt climate change, particularly those involving the Southern Ocean. However, records of millennial-scale variability from Antarctica dating to the last glacial maximum are rare and rely heavily on data from widely spaced ice cores, some of which show little variability through that time. Here, we present new data from closed-basin lakes in the Dry Valleys region of East Antarctica that show high-magnitude, high-frequency oscillations in surface level during the late Pleistocene synchronous with climate fluctuations elsewhere in the Southern Hemisphere. These data suggest a coherent Southern Hemisphere pattern of climate change on millennial time scales, at least in the Pacific sector, and indicate that any hypothesis concerning the origin of these events must account for synchronous changes in both high and temperate latitudes.

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

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


    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.

  2. 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

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


    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)).

  3. 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

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


    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)).

  4. Kame deltas provide evidence for a new glacial lake and suggest early glacial retreat from central Lower Michigan, USA

    Schaetzl, Randall J.; Lepper, Kenneth; Thomas, Sarah E.; Grove, Leslie; Treiber, Emma; Farmer, Alison; Fillmore, Austin; Lee, Jordan; Dickerson, Bethany; Alme, Kayleigh


    In association with an undergraduate Honors Seminar at Michigan State University, we studied two small kame deltas in north-central Lower Michigan. These recently identified deltas provide clear evidence for a previously unknown proglacial lake (Glacial Lake Roscommon) in this large basin located in an interlobate upland. Our first goal was to document and characterize the geomorphology of these deltas. Because both deltas are tied to ice-contact ridges that mark the former position of the retreating ice margin within the lake, our second goal was to establish the age of one of the deltas, thereby constraining the timing of ice retreat in this part of Michigan, for which little information currently exists. Both deltas are composed of well-sorted fine and medium sands with little gravel, and have broad, nearly flat surfaces and comparatively steep fronts. Samples taken from the upper 1.5 m of the deltas show little spatial variation in texture, aside from a general fining toward their outer margins. Gullies on the outer margins of both deltas probably postdate the formation of the deltas proper; we suggest that they formed by runoff during a permafrost period, subsequent to lake drawdown. We named the ice lobe that once covered this area the Mackinac Lobe, because it had likely advanced into the region across the Mackinac Straits area. Five of six optically stimulated luminescence (OSL) ages from one of the deltas had minimal scatter and were within ± 1000 years of one another, with a mean age of 23.1 ± 0.4 ka. These ages suggest that the Mackinac Lobe had started to retreat from the region considerably earlier than previously thought, even while ice was near its maximum extent in Illinois and Indiana, and the remainder of Michigan was ice-covered. This early retreat, which appears to coincide with a short-lived warm period indicated from the Greenland ice core, formed an "opening" that was at least occasionally flooded. Thick and deep, fine-textured deposits

  5. Suggestions and Effect on Bamboo Island Construction of Qiandao Lake%千岛湖竹岛建设建议及作用

    张乃华; 项瑜; 余觉来; 汪爱君; 黄超钢


    Suggestions and effect of bamboo island construction in Qiandao Lake were introduced. Some safeguard measures were put forward so as to provide the reference for the bamboo island construction of Qiandao Lake.%介绍了千岛湖竹岛建设的建议及竹岛的作用,并提出一些保障措施,以期为千岛湖竹岛的建设提供参考。

  6. Some Suggestions for the Construction of Kuihu Lake Provincial Wetland Park%奎湖省级湿地公园建设的几点建议



    本文根据奎湖湿地的实际情况,提出了奎湖湿地公园建设中存在的一些问题,并针对存在的问题,提出了一些建议和措施,为奎湖省级湿地公园建设提供参考。%In May, 2014, Anhui Provincial Wetland Conservation Center gave approval to planned construction of Kuihu Lake Provincial Wetland Park (pilot project), applied for by Forestry Bureau of Nanling County. At present, the construction of Kuihu Lake Provincial Wetland Park has started. According to the actualities of Kuihu Lake wetland, this paper pointed out some existing problems in its construction and put foward some specific suggestions and measures to provide reference for the construction of Kuihu Lake Provincial Wetland Park.

  7. Lake

    Wien, Carol Anne


    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…

  8. How Long Is Mono Contagious?

    ... 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 ...

  9. 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



    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.

  10. Mono pile foundation. Final report

    Lyngesen, S.; Brendstrup, C.


    The use of mono piles as foundations for maritime structures has been developed during the last decades. The installation requirements within the offshore sector have resulted in equipment enabling driving of piles up to 3-4 m to large penetration depths. The availability of this equipment has made the use of large mono piles feasible as foundations for structures like wind turbines. The mono pile foundations consists of three parts; the bare pile, a conical transition and a boat landing. All parts are prefitted at the yard in order to minimise the installation work that has to be carried out offshore. The study of a mono pile foundations for a 1.5 MW wind turbine has been conducted for two locations, Horns Rev and Roedsand. Three different water depths: 5, 8 and 11 m have been investigated in the study. The on-site welding between pile and conical transition is performed by an automatic welding machine. Final testing and eventually repair of the weld are conducted at least 16 hours after welding. This is followed by final installation of J-tube, tie-in to subsea cables and installation of the impressed current system for corrosive protection of the mono pile. The total cost for procurement and installation of the mono pile using the welded connection is estimated. The price does not include procurement and installation of access platform and boat landing. These costs are estimated to 250.000 DKK. Depending on water depth the cost of the pile ranges from 2,2 to 2,7 million DKK. Procurement and fabrication of the pile are approx. 75% of the total costs. The remaining 25% are due to installation. The total costs are very sensitive to the unit price of pile steel. During the project it became obvious that ice load has a very large influence on the dimensions of the mono pile. (EG)

  11. Climate inferences between paleontological, geochemical, and geophysical proxies in Late Pleistocene lacustrine sediments from Summer Lake, Oregon, western Great Basin

    Heaton, Eric; Thompson, Greg; Negrini, Rob; Wigand, Peter


    Paleontological, geochemical, and geophysical data from western Great Basin pluvial Summer Lake, Oregon have established a high resolution paleoclimate record during the late Pleistocene Mono Lake Excursion (~34.75 ka), Dansgaard-Oeschger interstadials 6-8, and the end of Heinrich Even 4 (~38 ka). Proxies of grain-size, magnetic susceptibility, carbon/nitrogen ratio, ostracode analysis and palynology from a depocenter core show new results with improved age control regarding high amplitude, high frequency changes in lake level, lake temperature, and regional precipitation and temperature which correspond directly with colder/warmer and respectively drier/wetter climates as documented with Northern Atlantic Greenland ice core data. Results from geophysical and geochemical analysis, and the presence of ostracode Cytherissa lacustris consistently demonstrate the correspondence of low lake conditions and colder water temperatures during Dansgaard-Oeschger stadials and the Mono Lake Excursion. The opposite holds true during interstadials. Smaller grain size, increases in carbon/nitrogen ratio and consistent absence of C. lacustris suggest periods of increased discharge into the lake, increased lake level, and warmer water temperatures. Warmer/wetter climate conditions are confirmed during interstadials 7 and 8 from pollen analysis. Existence of Atriplex, Rosaceae, Chrysothamnus and Ambrosia, and pollen ratios of Juniperus/Dip Pinus and (Rosaceae+Atriplex+Poaceae+Chrysothamnus+Ambrosia)/(Pinus+Picea+T. mertensiana+Sarcobatus) suggest warmer/wetter semi-arid woodland conditions during interstadials 7 and 8. This contrasts with absences in these pollens and pollen ratios indicating colder/drier continental montane woodland conditions during stadials and the Mono Lake Excursion. Increases in Juniper/Dip Pinus ratio suggest a warmer/wetter climate during interstadial 6 however additional proxies do not demonstrate comparative warmer/wetter climate, deeper lake level or

  12. Festival nimega Mono / Ivar Sakk

    Sakk, Ivar, 1962-


    Haapsalu graafilise disaini festival Haapsalu Linnagaleriis: sisaldab ülevaate- ja teemanäitust ning väikest sümpoosioni. Temaatilise aastanäituse motiiv on "MONO". Plakateid on ka välismaa tegijatelt. Kuraator Marko Kekishev

  13. Quaternary Eruptions of the Mono-Inyo Craters, California

    Bursik, M. I.; Pouget, S.; Mangan, M.; Marcaida, M.; Vazquez, J. A.


    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.

  14. 广西河湖水域岸线管理现状分析及建议%Current status analysis and suggestions for administration of river-lake shoreline and water area in Guangxi



    An introduction was made on the current status of river-lake shoreline and water area administration in Guangxi. The author analyzed the major problems and put forward suggestions for strengthening administration.%  介绍了广西河湖水域岸线管理现状,分析现阶段管理中存在的主要问题,并提出加强河湖水域及岸线管理的建议措施。

  15. 87Sr/86Sr Ratios in Carbonate From the Red Lake and Steep Rock Groups in Canada Suggest Rb-enriched Continental Crust was Influencing Seawater Chemistry Prior to 3.0 Ga

    Satkoski, A.; Fralick, P. W.; Beard, B. L.; Johnson, C.


    Previous work has suggested that prior to 2.5 Ga, Sr isotope compositions of seawater were essentially mantle buffered and the effects of continental weathering on seawater chemistry were negligible. To test this, we collected Sr isotope data from 2.93 and 2.80 Ga carbonates that are part of the Red Lake and Steep Rock groups (Canada), respectively. To better understand carbonate formation and any post-depositional alteration, Sr isotopes are considered with O isotopes and REEs, as well as Rb and Sr contents, including correction for decay of 87Rb. All samples have Y/Ho ratios higher than chondrite and have positive La anomalies, which, combined with low Rb contents suggests that clastic contamination is negligible. Samples we consider near pristine have δ18O (VSMOW) values >20‰. Samples with the highest Y/Ho ratios and largest La anomalies from Red Lake and Steep Rock have initial 87Sr/86Sr ratios of 0.7018-0.7020. This Sr isotope composition is significantly more radiogenic than contemporaneous mantle (0.7011-0.7012), especially at a time when the isotopic difference between the crust and mantle was much less than today. This implies that radiogenic continental crust was emergent and shed detritus into the world's oceans prior to 3.0 Ga, in contrast with proposals for submerged continental crust, but in line with new estimates that continental crust at 3.0 Ga was 60-70% of current volume. We contend that this large amount of crust combined with enhanced Archean weathering could account for the radiogenic Sr isotope compositions we report here, and suggests a significant impact from continental weathering on ocean chemistry during the Archean.

  16. Enantioselective recognition of mono-demethylated methoxychlor metabolites by the estrogen receptor.

    Miyashita, Masahiro; Shimada, Takahiro; Nakagami, Shizuka; Kurihara, Norio; Miyagawa, Hisashi; Akamatsu, Miki


    Metabolites of methoxychlor such as 2-(p-hydroxyphenyl)-2-(p-methoxyphenyl)-1,1,1-trichloroethane (mono-OH-MXC) and 2,2-bis(p-hydroxyphenyl)-1,1,1-trichloroethane (bis-OH-MXC), have estrogenic activity. Mono-OH-MXC is a chiral compound in which the carbon atom bridging two benzene rings is the chiral centre. In previous studies the estrogenic activity of racemic mono-OH-MXC has been measured, and the activity of each enantiomer of this compound has not yet been elucidated. In this study, we evaluated the estrogen receptor-binding activity of each enantiomer of mono-OH-MXC to clarify the enantioselective recognition by the estrogen receptor. (S)-mono-OH-MXC showed 3-fold higher binding activity than that of the (R) enantiomer. The activity of bis-OH-MXC was only 1.7-fold higher than that of (S)-mono-OH-MXC. This result suggests that the one hydroxy group and the orientation of the CCl3 group of mono- and bis-OH-MXCs are important for the interaction with the estrogen receptor. The result also points out the estrogenic activity of methoxychlor after metabolic activation in vivo, which predominantly produces the (S)-mono-OH-MXC, may be higher than estimated from the in vitro activity of racemic mixtures.

  17. Rare earth element and uranium-thorium variations in tufa deposits from the Mono Basin, CA

    Wilcox, E. S.; Tomascak, P. B.; Hemming, N.; Hemming, S. R.; Rasbury, T.; Stine, S.; Zimmerman, S. R.


    Samples of fossil tufa deposits from several localities in the Mono Basin, eastern California, were analyzed for trace element concentrations in order to better understand changes in lake composition in the past. These deposits were formed during the last glacial cycle, mostly during deglaciation (Benson et al., 1990, PPP). Three elevations are represented by the analyses. Samples from near Highway 167 were sampled between 2063 and 2069 m asl. Samples from near Thompson Road were sampled between 2015 and 2021 m. One layered mound was sampled at 1955 m. Concentrations of the lanthanide rare earth elements (REE), in particular the heavy/light (HREE/LREE) distributions, have been shown to be sensitive to alkalinity in modern saline lakes (e.g., Johannesson et al., 1994, GRL, 21, 773-776), and the same has been suggested for U/Th (Anderson et al., 1982, Science, 216, 514-516). Holocene to near-modern tufa towers exist in shallow water and around the current shoreline (1945 m). Tufa towers above 2000 m include a characteristic morphology termed thinolite, interpreted to represent pseudomorphs after the very cold water mineral ikaite. Most lower elevation towers do not have the thinolite morphology, but some layered tufa mounds at low elevations include several layers of thinolite, such as the one sampled for this project. Analyses were made on millimeter-scale bulk samples from tufa towers. Measurements were made on sample solutions with a Varian 820MS quadrupole ICP-MS. Mono Basin tufa samples have total REE concentrations ranging from 0.029 to 0.77 times average shales. Samples have flat to moderately HREE-enriched shale-normalized patterns with limited overall variability ([La/Lu]SN of 1.8 to 9.6) but with some variability in the slope of the HREE portion of the patterns. Tufa towers sampled from three elevations have (Gd/Lu)SN of 0.40 to 1.5. The REE patterns of most samples have small positive Ce anomalies, but a minority of samples, all from the layered tufa mound

  18. Investigations of the Origin of the Magnetic Remanence in Late Pleistocene Lacustrine Sediments in the Mono Basin, CA

    Vasquez, N.; Corley, A. D.


    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

  19. Stochastic modeling of Lake Van water level time series with jumps and multiple trends

    H. Aksoy


    Full Text Available 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.

  20. Embryotoxicity of an extract from Great Lakes lake trout to rainbow trout and lake trout

    Wright, P.J.; Tillitt, D.E. [National Biological Service, Columbia, MO (United States). Midwest Science Center


    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.

  1. Permeability of mono- and bi-dispersed porous media

    Kim S.J.


    Full Text Available In this study, the permeability of mono- and bi-dispersed porous media is considered. The effects of the particle size distribution and the packing structure of particles on the permeability are investigated experimentally and analytically. Both experimental and analytic results suggest that the particlesize distribution is close to the log-normal distribution, and the permeability of the mono-dispersed porous media quasi-linearly decreases as the range of the particle size distribution increases. On the other hand, the effect of packing structure of particles on the permeability is shown to be negligible.The permeability of the bidispersed porous media quasi-linearly decreases as the range of cluster size increases, and nearly independent of the particle size distribution. The present model is valid over the range of parameters typically found in heat transfer applications.

  2. Mono- versus polydrug abuse patterns among publicly funded clients

    Relyea George


    Full Text Available Abstract To examine patterns of mono- versus polydrug abuse, data were obtained from intake records of 69,891 admissions to publicly funded treatment programs in Tennessee between 1998 and 2004. While descriptive statistics were employed to report frequency and patterns of mono- and polydrug abuse by demographic variables and by study years, bivariate logistic regression was applied to assess the probability of being a mono- or polydrug abuser for a number of demographic variables. The researchers found that during the study period 51.3% of admissions reported monodrug abuse and 48.7% reported polydrug abuse. Alcohol, cocaine, and marijuana were the most commonly abused substances, both alone and in combination. Odds ratio favored polydrug abuse for all but one drug category–other drugs. Gender did not affect drug abuse patterns; however, admissions for African Americans and those living in urban areas exhibited higher probabilities of polydrug abuse. Age group also appeared to affect drug abuse patterns, with higher odds of monodrug abuse among minors and adults over 45 years old. The discernable prevalence of polydrug abuse suggests a need for developing effective prevention strategies and treatment plans specific to polydrug abuse.

  3. Possible Recording of the Hilina Pali Excursion in the Mono Basin, California

    Coe, R.; Liddicoat, J.


    Inclination of about negative 40˚ in basalt from Kilauea volcano, Hawaii (Teanby et al., 2002), that is assigned an age of about 18,000 radiocarbon years (uncorrected)(Coe et al., 1978, after Rubin and Berthold, 1961) and an excursion in northeastern China at Changbaishan Volcano of similar age from Ar40/Ar39 dates (Singer et al., 2011) that was interpreted to be the Blake Subchron (Zhu et al., 2000) using K/Ar (Liu, 1987) and Ar40/39 dates (Lin, 1999), might be recorded as shallow positive inclination in lacustrine siltstone in the bank of Wilson Creek in the Mono Basin, CA. The siltstone was deposited in Pleistocene Lake Russell, of which Mono Lake is the remnant, and was exposed when Wilson Creek was incised as the shoreline of Mono Lake receded (Lajoie, 1968). Basaltic and rhyolitic volcanic ash layers exposed in the bank of the creek are stratigraphic markers that have been important for studies of the Mono Lake Excursion (Denham and Cox, 1971; Liddicoat and Coe, 1979; Liddicoat, 1992; Coe and Liddicoat, 1994) and Pleistocene climate in the U.S. Great Basin (Zimmerman et al., 2006). Those ash layers likewise are useful for locating paleomagnetic directions along strike that might be the negative inclination in Hawaii named the Hilina Pali Excursion (Teanby et al., 2002). The portion of the lacustine section exposed along Wilson Creek that is of interest records waveform Delta in Lund et al. (1988) in Subunit E of Lajoie (1993) that is bracketed by ash layers 12 and 13; in Lajoie (1968), those ash layers are numbered 8 and 7, respectively. About midway in Subunit E, which has a thickness of 1.1 m, the inclination is about 15˚ in four back-to-back horizons that span 8 cm. The subsamples, each 2 cm thick, were treated by either alternating field or thermal demagnetization. The Virtual Geomagnetic Pole (VGP) for the horizon with the shallowest inclination (14.9˚) is 53.8˚ N, 22.7˚ E (n = 6, Alpha-95 = 2.3˚), and the VGPs within waveform Delta when followed

  4. Resonant mono Higgs at the LHC

    Basso, Lorenzo


    In recent years, the production of a SM particle with large missing transverse momentum, dubbed mono-X searches, have gained increasing attention. After the discovery of the Higgs boson in 2012, the run-II of the LHC will now scrutinise its properties, looking for BSM physics. In particular, one could search for mono-Higgs signals, that are typically studied in models addressing dark matter. However, this signal can appear also in models addressing the neutrino masses, if additional heavier neutrinos with masses at the electroweak scale are present. The latter will couple to the SM neutrinos and the Higgs boson, yielding a type of mono-Higgs signal not considered for dark matter: the resonant production of a Higgs boson and missing energy. In this paper, we address the LHC exclusion power of the latter with dedicated detector simulations, and reinterpret it in a benchmark model for neutrino mass generation.

  5. Genetic structure and hierarchical population divergence history of Acer mono var. mono in South and Northeast China.

    Chunping Liu

    Full Text Available Knowledge of the genetic structure and evolutionary history of tree species across their ranges is essential for the development of effective conservation and forest management strategies. Acer mono var. mono, an economically and ecologically important maple species, is extensively distributed in Northeast China (NE, whereas it has a scattered and patchy distribution in South China (SC. In this study, the genetic structure and demographic history of 56 natural populations of A. mono var. mono were evaluated using seven nuclear microsatellite markers. Neighbor-joining tree and STRUCTURE analysis clearly separated populations into NE and SC groups with two admixed-like populations. Allelic richness significantly decreased with increasing latitude within the NE group while both allelic richness and expected heterozygosity showed significant positive correlation with latitude within the SC group. Especially in the NE region, previous studies in Quercus mongolica and Fraxinus mandshurica have also detected reductions in genetic diversity with increases in latitude, suggesting this pattern may be common for tree species in this region, probably due to expansion from single refugium following the last glacial maximum (LGM. Approximate Bayesian Computation-based analysis revealed two major features of hierarchical population divergence in the species' evolutionary history. Recent divergence between the NE group and the admixed-like group corresponded to the LGM period and ancient divergence of SC groups took place during mid-late Pleistocene period. The level of genetic differentiation was moderate (FST  = 0.073; G'ST  = 0.278 among all populations, but significantly higher in the SC group than the NE group, mirroring the species' more scattered distribution in SC. Conservation measures for this species are proposed, taking into account the genetic structure and past demographic history identified in this study.

  6. Genetic structure and hierarchical population divergence history of Acer mono var. mono in South and Northeast China.

    Liu, Chunping; Tsuda, Yoshiaki; Shen, Hailong; Hu, Lijiang; Saito, Yoko; Ide, Yuji


    Knowledge of the genetic structure and evolutionary history of tree species across their ranges is essential for the development of effective conservation and forest management strategies. Acer mono var. mono, an economically and ecologically important maple species, is extensively distributed in Northeast China (NE), whereas it has a scattered and patchy distribution in South China (SC). In this study, the genetic structure and demographic history of 56 natural populations of A. mono var. mono were evaluated using seven nuclear microsatellite markers. Neighbor-joining tree and STRUCTURE analysis clearly separated populations into NE and SC groups with two admixed-like populations. Allelic richness significantly decreased with increasing latitude within the NE group while both allelic richness and expected heterozygosity showed significant positive correlation with latitude within the SC group. Especially in the NE region, previous studies in Quercus mongolica and Fraxinus mandshurica have also detected reductions in genetic diversity with increases in latitude, suggesting this pattern may be common for tree species in this region, probably due to expansion from single refugium following the last glacial maximum (LGM). Approximate Bayesian Computation-based analysis revealed two major features of hierarchical population divergence in the species' evolutionary history. Recent divergence between the NE group and the admixed-like group corresponded to the LGM period and ancient divergence of SC groups took place during mid-late Pleistocene period. The level of genetic differentiation was moderate (FST  = 0.073; G'ST  = 0.278) among all populations, but significantly higher in the SC group than the NE group, mirroring the species' more scattered distribution in SC. Conservation measures for this species are proposed, taking into account the genetic structure and past demographic history identified in this study.

  7. Lake trout rehabilitation in Lake Ontario

    Elrod, Joseph H.; O'Gorman, Robert; Schneider, Clifford P.; Eckert, Thomas H.; Schaner, Ted; Bowlby, James N.; Schleen, Larry P.


    Attempts to maintain the native lake trout (Salvelinus namaycush) population in Lake Ontario by stocking fry failed and the species was extirpated by the 1950s. Hatchery fish stocked in the 1960s did not live to maturity because of sea lamprey (Petromyzon marinus) predation and incidental commercial harvest. Suppression of sea lampreys began with larvicide treatments of Lake Ontario tributaries in 1971 and was enhanced when the tributaries of Oneida Lake and Lake Erie were treated in the 1980s. Annual stocking of hatchery fish was resumed with the 1972 year class and peaked at about 1.8 million yearlings and 0.3 million fingerlings from the 1985–1990 year classes. Survival of stocked yearlings declined over 50% in the 1980 s and was negatively correlated with the abundance of lake trout > 550 mm long (r = −0.91, P < 0.01, n = 12). A slot length limit imposed by the State of New York for the 1988 fishing season reduced angler harvest. Angler harvest in Canadian waters was 3 times higher in eastern Lake Ontario than in western Lake Ontario. For the 1977–1984 year classes, mean annual survival rate of lake trout age 6 and older was 0.45 (range: 0.35–0.56). In U.S. waters during 1985–1992, the total number of lake trout harvested by anglers was about 2.4 times greater than that killed by sea lampreys. The number of unmarked lake trout < 250 mm long in trawl catches in 1978–1992 was not different from that expected due to loss of marks and failure to apply marks at the hatchery, and suggested that recruitment of naturally-produced fish was nil. However, many of the obstacles which may have impeded lake trout rehabilitation in Lake Ontario during the 1980s are slowly being removed, and there are signs of a general ecosystem recovery. Significant recruitment of naturally produced lake trout by the year 2000, one interim objective of the rehabilitation plan for the Lake, may be achieved.

  8. Search for Exotic mono-jet and mono-photon signatures with the ATLAS detector

    Rezvani Reyhaneh


    Full Text Available Mono-jet and mono-photon signatures are final states in a variety of scenarios beyond the Standard Model, such as the Large Extra Dimension models, gauge-mediated SUSY breaking scenarios, and models with pair production of Weakly Interacting Massive Particles considered as dark matter candidates. The produced exotic particles do not interact with the detector, resulting in missing transverse energy. The results of searches, performed in the ATLAS experiment at the LHC, for new physics in final states with an energetic jet or photon and large missing transverse energy are presented. The mono-jet search is performed using both 4.6 fb−1 of 7 TeV and 10.5 fb−1 of 8 TeV data, while the mono-photon results correspond to 4.6 fb−1 of 7 TeV data.

  9. 21 CFR 172.834 - Ethoxylated mono- and diglycerides.


    ... ethoxylated mono-and diglycerides (polyoxyethylene (20) mono- and diglycerides of fatty acids) (polyglycerate... labeling it shall be followed by either “polyoxyethylene (20) mono-and diglycerides of fatty acids” or... (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) FOOD ADDITIVES PERMITTED FOR DIRECT ADDITION TO FOOD...

  10. Lake trout in the Great Lakes: Basin-wide stock collapse and binational restoration

    Hansen, Michael J.; Taylor, William W.; Ferreri, C. Paola


    The lake trout (Salvelinus namaycush) was important to the human settlement of each of the Great Lakes, and underwent catastrophic collapses in each lake in the nineteenth and twentieth centuries. The timing of lake trout stock collapses were different in each lake, as were the causes of the collapses, and have been the subject of much scientific inquiry and debate. The purpose of this chapter is to summarize and review pertinent information relating historical changes in Great Lakes lake trout stocks, binational efforts to restore those stocks, and progress toward stock restoration. This presentation attempts to generalize patterns across the Great Lakes, rather than to focus within each lake. Lake specific analyses have been used to understand lake specific causes and effects, but there is continuing debate about some of these causes and effects. A basinwide review may suggest mechanisms for observed changes that are not evident by lake specific analysis.

  11. Lake Cadagno

    Tonolla, Mauro; Storelli, Nicola; Danza, Francesco


    Lake Cadagno (26 ha) is a crenogenic meromictic lake located in the Swiss Alps at 1921 m asl with a maximum depth of 21 m. The presence of crystalline rocks and a dolomite vein rich in gypsum in the catchment area makes the lake a typical “sulphuretum ” dominated by coupled carbon and sulphur cyc...


    Petre GÂŞTESCU


    Full Text Available Limnology is a border discipline between geography, hydrology and biology, and is also closely connected with other sciences, from it borrows research methods. Physical limnology (the geography of lakes, studies lake biotopes, and biological limnology (the biology of lakes, studies lake biocoenoses. The father of limnology is the Swiss scientist F.A. Forel, the author of a three-volume entitled Le Leman: monographie limnologique (1892-1904, which focuses on the geology physics, chemistry and biology of lakes. He was also author of the first textbook of limnology, Handbuch der Seenkunde: allgemeine Limnologie,(1901. Since both the lake biotope and its biohydrocoenosis make up a single whole, the lake and lakes, respectively, represent the most typical systems in nature. They could be called limnosystems (lacustrine ecosystems, a microcosm in itself, as the American biologist St.A. Forbes put it (1887.

  13. Scour properties of mono bucket foundation

    Stroescu, Ionut Emanuel; Frigaard, Peter Bak


    Field experience proved that the Mono Bucket Foundations (MBFs) have good response against scour development. Moreover, the ratio between large diameter (bucket lid) and the small diameter (shaft tower) is the driving parameter for the process of erosion/backfill, like scour protection diameter...... in the case of scour protected monopiles. However, the structural design to reduce the scour development for MBFs is still open to optimization. The influences of parameters that generate backfill and scour, the transfer load webs and the misalignment with seabed, have not been systematically studied until...

  14. Late Pleistocene eruptive history of the Mono Craters rhyolites, eastern California, from U-Th dating of explosive and effusive products

    Marcaida, M.; Vazquez, J. A.; Calvert, A. T.; Miller, J. S.


    During late Pleistocene-Holocene time, repeated explosive and effusive eruptions of high-silica rhyolite magma south of Mono Lake, California, have produced a chain of massive domes known as the Mono Craters and a time-series of tephra deposits preserved in sediments of the Wilson Creek formation of ancestral Mono Lake. The record of late Holocene volcanism at Mono Craters is relatively well constrained by tephrostratigraphy and 14C dating, and the timing of late Pleistocene eruptions is similarly well constrained by tephrochronology and magnetostratigraphy of the Wilson Creek formation. However, the chronology of eruptions for the Mono Craters chain, comprising at least 28 individual domes, has thus far been based on age estimates from hydration rind dating of obsidian that is highly dependent on local calibration. We constrain the timing of late Pleistocene dome emplacement by linking independently dated Wilson Creek tephras to their dome equivalents in the Mono Craters using combined titanomagnetite geochemistry and U-Th geochronology. Ion microprobe 238U-230Th dating of unpolished allanite and zircon rims gives isochron dates of ca. 42 ka, ca. 38 ka, ca. 26 ka, and ca. 20 ka for domes 19, 24, 31 (newly recognized), and 11 of the Mono Craters, respectively. These domes are biotite-bearing rhyolites with titanomagnetites that are compositionally identical to those from several Wilson Creek tephras. Specifically, we correlate Ash 15, Ash 7, and Ash 3 of the Wilson Creek formation to domes 19, 31, and 11 of the Mono Craters, respectively, based on matching titanomagnetite compositions and indistinguishable U-Th ages. 40Ar/39Ar dating of single sanidines from domes 19 and 31 yield mean dates that are 10 k.y. older than their corresponding U-Th dates, likely due to excess argon from melt inclusions and/or incompletely re-equilibrated antecrysts. Based on our new U-Th isochron date of ca. 34 ka for allanite-zircon from Ash 8 pumice and the ca. 26-27 ka age of Ash 7

  15. Ecology under lake ice.

    Hampton, Stephanie E; Galloway, Aaron W E; Powers, Stephen M; Ozersky, Ted; Woo, Kara H; Batt, Ryan D; Labou, Stephanie G; O'Reilly, Catherine M; Sharma, Sapna; Lottig, Noah R; Stanley, Emily H; North, Rebecca L; Stockwell, Jason D; Adrian, Rita; Weyhenmeyer, Gesa A; Arvola, Lauri; Baulch, Helen M; Bertani, Isabella; Bowman, Larry L; Carey, Cayelan C; Catalan, Jordi; Colom-Montero, William; Domine, Leah M; Felip, Marisol; Granados, Ignacio; Gries, Corinna; Grossart, Hans-Peter; Haberman, Juta; Haldna, Marina; Hayden, Brian; Higgins, Scott N; Jolley, Jeff C; Kahilainen, Kimmo K; Kaup, Enn; Kehoe, Michael J; MacIntyre, Sally; Mackay, Anson W; Mariash, Heather L; McKay, Robert M; Nixdorf, Brigitte; Nõges, Peeter; Nõges, Tiina; Palmer, Michelle; Pierson, Don C; Post, David M; Pruett, Matthew J; Rautio, Milla; Read, Jordan S; Roberts, Sarah L; Rücker, Jacqueline; Sadro, Steven; Silow, Eugene A; Smith, Derek E; Sterner, Robert W; Swann, George E A; Timofeyev, Maxim A; Toro, Manuel; Twiss, Michael R; Vogt, Richard J; Watson, Susan B; Whiteford, Erika J; Xenopoulos, Marguerite A


    Winter conditions are rapidly changing in temperate ecosystems, particularly for those that experience periods of snow and ice cover. Relatively little is known of winter ecology in these systems, due to a historical research focus on summer 'growing seasons'. We executed the first global quantitative synthesis on under-ice lake ecology, including 36 abiotic and biotic variables from 42 research groups and 101 lakes, examining seasonal differences and connections as well as how seasonal differences vary with geophysical factors. Plankton were more abundant under ice than expected; mean winter values were 43.2% of summer values for chlorophyll a, 15.8% of summer phytoplankton biovolume and 25.3% of summer zooplankton density. Dissolved nitrogen concentrations were typically higher during winter, and these differences were exaggerated in smaller lakes. Lake size also influenced winter-summer patterns for dissolved organic carbon (DOC), with higher winter DOC in smaller lakes. At coarse levels of taxonomic aggregation, phytoplankton and zooplankton community composition showed few systematic differences between seasons, although literature suggests that seasonal differences are frequently lake-specific, species-specific, or occur at the level of functional group. Within the subset of lakes that had longer time series, winter influenced the subsequent summer for some nutrient variables and zooplankton biomass. © 2016 The Authors. Ecology Letters published by CNRS and John Wiley & Sons Ltd.

  16. Yellowstone Lake Nanoarchaeota

    Scott eClingenpeel


    Full Text Available Considerable Nanoarchaeota novelty and diversity were encountered in Yellowstone Lake, Yellowstone National Park, where sampling targeted lake floor hydrothermal vent fluids, streamers and sediments associated with these vents, and in planktonic photic zones in three different regions of the lake. Significant homonucleotide repeats (HR were observed in pyrosequence reads and in near full-length Sanger sequences, averaging 112 HR per 1,349 bp clone and could confound diversity estimates derived from pyrosequencing, resulting in false nucleotide insertions or deletions (indels. However, Sanger sequencing of two different sets of PCR clones (110 bp, 1349 bp demonstrated that at least some of these indels are real. The majority of the Nanoarchaeota PCR amplicons were vent associated; however, curiously, one relatively small Nanoarchaeota OTU (70 pyrosequencing reads was only found in photic zone water samples obtained from a region of the lake furthest removed from the hydrothermal regions of the lake. Extensive pyrosequencing failed to demonstrate the presence of an Ignicoccus lineage in this lake, suggesting the Nanoarchaeota in this environment are associated with novel Archaea hosts. Defined phylogroups based on near full-length PCR clones document the significant Nanoarchaeota 16S rRNA gene diversity in this lake and firmly establish a terrestrial clade distinct from the marine Nanoarcheota as well as from other geographical locations.

  17. Yellowstone lake nanoarchaeota.

    Clingenpeel, Scott; Kan, Jinjun; Macur, Richard E; Woyke, Tanja; Lovalvo, Dave; Varley, John; Inskeep, William P; Nealson, Kenneth; McDermott, Timothy R


    Considerable Nanoarchaeota novelty and diversity were encountered in Yellowstone Lake, Yellowstone National Park (YNP), where sampling targeted lake floor hydrothermal vent fluids, streamers and sediments associated with these vents, and in planktonic photic zones in three different regions of the lake. Significant homonucleotide repeats (HR) were observed in pyrosequence reads and in near full-length Sanger sequences, averaging 112 HR per 1349 bp clone and could confound diversity estimates derived from pyrosequencing, resulting in false nucleotide insertions or deletions (indels). However, Sanger sequencing of two different sets of PCR clones (110 bp, 1349 bp) demonstrated that at least some of these indels are real. The majority of the Nanoarchaeota PCR amplicons were vent associated; however, curiously, one relatively small Nanoarchaeota OTU (71 pyrosequencing reads) was only found in photic zone water samples obtained from a region of the lake furthest removed from the hydrothermal regions of the lake. Extensive pyrosequencing failed to demonstrate the presence of an Ignicoccus lineage in this lake, suggesting the Nanoarchaeota in this environment are associated with novel Archaea hosts. Defined phylogroups based on near full-length PCR clones document the significant Nanoarchaeota 16S rRNA gene diversity in this lake and firmly establish a terrestrial clade distinct from the marine Nanoarcheota as well as from other geographical locations.

  18. On mono-W signatures in spin-1 simplified models

    Haisch, Ulrich [Oxford Univ. (United Kingdom). Rudolf Peierls Centre for Theoretical Physics; CERN, Geneva (Switzerland). Theory Div.; Kahlhoefer, Felix [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Tait, Tim M.P. [California Univ., Irvine, CA (United States). Dept. of Physics and Astronomy


    The potential sensitivity to isospin-breaking effects makes LHC searches for mono-W signatures promising probes of the coupling structure between the Standard Model and dark matter. It has been shown, however, that the strong sensitivity of the mono-W channel to the relative magnitude and sign of the up-type and down-type quark couplings to dark matter is an artefact of unitarity violation. We provide three different solutions to this mono-W problem in the context of spin-1 simplified models and briefly discuss the impact that our findings have on the prospects of mono-W searches at future LHC runs.

  19. On mono-W signatures in spin-1 simplified models

    Ulrich Haisch


    Full Text Available The potential sensitivity to isospin-breaking effects makes LHC searches for mono-W signatures promising probes of the coupling structure between the Standard Model and dark matter. It has been shown, however, that the strong sensitivity of the mono-W channel to the relative magnitude and sign of the up-type and down-type quark couplings to dark matter is an artifact of unitarity violation. We provide three different solutions to this mono-W problem in the context of spin-1 simplified models and briefly discuss the impact that our findings have on the prospects of mono-W searches at future LHC runs.

  20. Deposits of the most recent eruption in the Southern Mono Craters, California: Description, interpretation and implications for regional marker tephras

    Bursik, Marcus; Sieh, Kerry; Meltzner, Aron


    The penultimate eruption in the Mono Craters, Mono County, CA, USA, occurred in the southern section of the volcanic chain, and is herein named the South Mono eruption. The South Mono eruption occurred in 594-648cal A.D., and its products consist of widespread Plinian and phreatomagmatic fall, surge and pyroclastic flow deposits. The explosive deposits can be broken into Basal, Orange-Brown (surge dominated) and Upper subunits. The eruptive phase represented by the Upper beds was the most intense and voluminous, dispersing tephra over a wide region of eastern CA and western NV. South Coulee was the only effusive product of the eruption, and comprises the vast majority of the c. 0.4 cu km dense-rock equivalent (DRE) volume. The tephra overlies the deposits of Wilson Butte to the south, and is correlated herein with Wood's Tephra 2, and Walker Lake and Turupah Flats regional marker tephra layers. Other dates for these regional tephras may be the result of dating ash redeposited in debris flow events following fire.

  1. Microbiology of Lonar Lake and other soda lakes.

    Antony, Chakkiath Paul; Kumaresan, Deepak; Hunger, Sindy; Drake, Harold L; Murrell, J Colin; Shouche, Yogesh S


    Soda lakes are saline and alkaline ecosystems that are believed to have existed throughout the geological record of Earth. They are widely distributed across the globe, but are highly abundant in terrestrial biomes such as deserts and steppes and in geologically interesting regions such as the East African Rift valley. The unusual geochemistry of these lakes supports the growth of an impressive array of microorganisms that are of ecological and economic importance. Haloalkaliphilic Bacteria and Archaea belonging to all major trophic groups have been described from many soda lakes, including lakes with exceptionally high levels of heavy metals. Lonar Lake is a soda lake that is centered at an unusual meteorite impact structure in the Deccan basalts in India and its key physicochemical and microbiological characteristics are highlighted in this article. The occurrence of diverse functional groups of microbes, such as methanogens, methanotrophs, phototrophs, denitrifiers, sulfur oxidizers, sulfate reducers and syntrophs in soda lakes, suggests that these habitats harbor complex microbial food webs that (a) interconnect various biological cycles via redox coupling and (b) impact on the production and consumption of greenhouse gases. Soda lake microorganisms harbor several biotechnologically relevant enzymes and biomolecules (for example, cellulases, amylases, ectoine) and there is the need to augment bioprospecting efforts in soda lake environments with new integrated approaches. Importantly, some saline and alkaline lake ecosystems around the world need to be protected from anthropogenic pressures that threaten their long-term existence.

  2. Lake trout rehabilitation in Lake Erie: a case history

    Cornelius, Floyd C.; Muth, Kenneth M.; Kenyon, Roger


    Native lake trout (Salvelinus namaycush) once thrived in the deep waters of eastern Lake Erie. The impact of nearly 70 years of unregulated exploitation and over 100 years of progressively severe cultural eutrophication resulted in the elimination of lake trout stocks by 1950. Early attempts to restore lake trout by stocking were unsuccessful in establishing a self-sustaining population. In the early 1980s, New York's Department of Environmental Conservation, Pennsylvania's Fish and Boat Commission, and the U.S. Fish and Wildlife Service entered into a cooperative program to rehabilitate lake trout in the eastern basin of Lake Erie. After 11 years of stocking selected strains of lake trout in U.S. waters, followed by effective sea lamprey control, lake trout appear to be successfully recolonizing their native habitat. Adult stocks have built up significantly and are expanding their range in the lake. Preliminary investigations suggest that lake trout reproductive habitat is still adequate for natural reproduction, but natural recruitment has not been documented. Future assessments will be directed toward evaluation of spawning success and tracking age-class cohorts as they move through the fishery.

  3. Stochastic modeling of Lake Van water level time series with jumps and multiple trends

    H. Aksoy


    Full Text Available In 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 shows that change in the water level is related to the water budget of the lake. In this study, a stochastic model is generated using the measured monthly water level data of the lake. The model is derived after removal of trend and periodicity in the data set. Trend observed in the lake water level time series is fitted by mono- and multiple-trend lines. For the multiple-trend, the time series is first divided into homogeneous segments by means of SEGMENTER, segmentation software. Four segments are found meaningful practically each fitted with a trend line. Two models considering mono- and multiple-trend time series are developed. The multiple-trend model is found better for planning future development in surrounding areas of the lake.

  4. Mono- and combined antimicrobial agents efficiency in experimental wound infection

    Наталія Ігорівна Філімонова


    Full Text Available Modern problems of antibiotic therapy are shown by wide range of side effects, both on organism and microbiological levels: the spread of allergies, toxic for organ systems reactions, dysbiosis development, and resistant pathogens formation and dissemination. Therefore the necessity of search for new effective drugs with significant antimicrobial activity applied for the wounds treatment arises. Development of combined remedies on the background of different origin antimicrobial agents’ derivatives is one of the fight directions against infectious diseases in the skin pathology. Recently among the existing antimicrobial agents one should focus on antiseptic drugs, due to degenerative and dysfunctional effect on microbial cell.Aim of research. The comparison of mono- and combined antimicrobial agents chemotherapeutic efficiency in the treatment of localized purulent infection under experimental conditions.Metods. The study of chemotherapeutic efficiency was carried out on the model of localized purulent Staphylococcus infection on albino mice weighting 14 – 16 g. S.aureus ATCC 25923 strains were used as infectious agents. The contamination was performed subcutaneously to the right side of mice’s skin after depilation. The animals were randomly divided into 4 groups: the 1st group – infected mice without treatment (control; the 2nd group – infected mice treated with a ciprofloxacin; the 3rd group – infected mice treated with a Ciprofloxacin and Decamethoxin combination; the 4th group – infected mice treated with a combined drug on the base of mutual prodrugs (Hexamethylenetetramine and Phenyl salicylate.Results. The efficiency of mono- and combined antimicrobial agents under experimental Staphylococcus wound infection conditions was studied. It was found that localized purulent staph center was formed more slowly in comparison with control and mono preparation use (2nd group of animals. The average index of skin lesions in comparison

  5. Evolution of alkaline lakes - Lake Van case study

    Tillman Meyer, Felix; Viehberg, Finn; Bahroun, Sonya; Wolf, Annabel; Immenhauser, Adrian; Kwiecien, Ola


    Lake Van in Eastern Anatolia (Turkey) is the largest terminal soda lake on Earth. The lake sedimentary profile covers ca. 600 ka (Stockhecke et al. 2014) Based on lithological changes, the presence of freshwater microfossils and close-to-freshwater pH value in the pore water, members of ICDP PALEOVAN concluded that Lake Van might have started as an open lake. Here we show paleontological and geochemical evidence in favour of this idea and constrain the time, when Lake Van likely transformed into a closed lake. Additionally we provide the first conceptual model of how this closure may have happened. Our archives of choice are inorganic and biogenic carbonates, separated by wet sieving. We identified microfossil assemblages (fraction > 125 µm) and performed high-resolution oxygen isotope (delta18O) and elemental (Mg/Ca, Sr/Ca) analyses of the fraction food supply. These two aspects point to an increasing salinity in a shallowing lake. The delta18O values of inorganic carbonates are relatively low during the initial phase of Lake Van and increase abruptly (ca. 7‰) after 530 ka BP. At approximately the same time combination of Sr/Ca and Mg/Ca data suggest first occurrence of aragonite. Again, these findings suggest geochemical changes of the lake water concurrent with transition documented by microfossils. Comparison between Lake Van and Lake Ohrid (Lacey et al. 2016) delta18O data, precludes regional climate change (e.g.: increased evaporation) as the main driver of observed changes. With no evidence for increased volcanic or tectonic activity (e.g.: tephra layers, deformation structures, slumping) in the Lake Van sedimentary profile around 530 ka, it seems unlikely that a pyroclastic flow blocked the outflow of the lake. Alternatively, a portion of inflow has been diverged which might have caused a change in the hydrological balance and lake level falling below its outlet. However, as no geomorphological data confirming this scenario yet exist, it is only a

  6. Plasma etching on large-area mono-, multi- and quasi-mono crystalline silicon

    Davidsen, Rasmus Schmidt; Schmidt, Michael Stenbæk; Boisen, Anja


    We use plasma etched Black Si (BS)[1][2] nanostructures to achieve low reflectance due to the resulting graded refractive index at the Si-air interface. The goal of this investigation is to develop a suitable texturing method for Si solar cells. Branz et al. [3]report below 3% average reflectance...... advantages such as; (i) excellent light trapping, (ii) dry, single-sided and scalable process method and (iii) etch independence on crystallinity of Si, RIE-texturing has so far not been proven superior to standard wet texturing, primarily as a result of lower power conversion efficiency due to increased...... using maskless RIE in a O2 and SF6 plasma, and the surface topology was optimized for solar cell applications by varying gas flows, pressure, power and process time. The starting substrates were 156x156 mm p-type, CZ mono-, multi- and quasi-mono crystalline Si wafers, respectively, with a thickness...

  7. Emotions in freely varying and mono-pitched vowels, acoustic and EGG analyses.

    Waaramaa, Teija; Palo, Pertti; Kankare, Elina


    Vocal emotions are expressed either by speech or singing. The difference is that in singing the pitch is predetermined while in speech it may vary freely. It was of interest to study whether there were voice quality differences between freely varying and mono-pitched vowels expressed by professional actors. Given their profession, actors have to be able to express emotions both by speech and singing. Electroglottogram and acoustic analyses of emotional utterances embedded in expressions of freely varying vowels [a:], [i:], [u:] (96 samples) and mono-pitched protracted vowels (96 samples) were studied. Contact quotient (CQEGG) was calculated using 35%, 55%, and 80% threshold levels. Three different threshold levels were used in order to evaluate their effects on emotions. Genders were studied separately. The results suggested significant gender differences for CQEGG 80% threshold level. SPL, CQEGG, and F4 were used to convey emotions, but to a lesser degree, when F0 was predetermined. Moreover, females showed fewer significant variations than males. Both genders used more hypofunctional phonation type in mono-pitched utterances than in the expressions with freely varying pitch. The present material warrants further study of the interplay between CQEGG threshold levels and formant frequencies, and listening tests to investigate the perceptual value of the mono-pitched vowels in the communication of emotions.

  8. Intercultural Interactions of Mono-Cultural, Mono-Lingual Local Students in Small Group Learning Activities: A Bourdieusian Analysis

    Colvin, Cassandra; Fozdar, Farida; Volet, Simone


    This research examines the understandings and experiences of mono-cultural, mono-lingual local students in relation to intercultural interactions within small group learning activities at university. Bourdieu's concepts of field, habitus and capital are employed to illuminate a number of barriers to intercultural interaction. Using qualitative…

  9. Intercultural Interactions of Mono-Cultural, Mono-Lingual Local Students in Small Group Learning Activities: A Bourdieusian Analysis

    Colvin, Cassandra; Fozdar, Farida; Volet, Simone


    This research examines the understandings and experiences of mono-cultural, mono-lingual local students in relation to intercultural interactions within small group learning activities at university. Bourdieu's concepts of field, habitus and capital are employed to illuminate a number of barriers to intercultural interaction. Using qualitative…

  10. Investigations About the Recording of the Palaeomagnetic Field in the Mono Basin, CA, in Siltstone from a Granitic Provenance

    Liddicoat, Joseph; Coe, Robert


    For more than three decades, Reidar Lovlie did innovative laboratory and field experiments that advanced our understanding about how sediments acquire a remanent magnetization (Lovlie, 1979, and his subsequent publications about that research). The investigations we and our students have done with lacustrine sediments deposited during the late Pleistocene in the Mono Basin, CA, have benefited from those experiments. One of Lovlie's laboratory experiments that was especially useful in our investigation of the role of relative field intensity (RFI) during a rapidly changing field, the Mono Lake Excursion (MLE; Coe and Liddicoat, 1994), was his study of suspended magnetic grains in slowly curing epoxy resin as the field strength was varied (Lovlie, 1993). More recently we did comparative field and laboratory experiments with sediments from different depositional environments in the Mono Basin that help to explain the recording of the palaeomagnetic field in unweathered siltstone derived from a granitic provenance in the California Sierra Nevada. Our investigations are possible because inclination, declination, and RFI using alternating field and thermal demagnetization and intensity normalizing experiments of magnetic susceptibility (k), saturation isothermal remanent magnetization (SIRM), and anhysteretic remanent magnetization (ARM)(Lund et al., 2005) can be measured with precision for localities separated by as much as 15 kilometres using volcanic ash beds as marker horizons. In addition to making the comparison between localities in the Mono Basin that record the MLE, we have done that for a time interval following the MLE also in the Mono Basin where the palaeomagnetic directions are anomalous compared to secular variation (waveform Delta in Lund et al., 1988; Liddicoat and Coe, 2013). In that interval the RFI is nearly double the RFI during the MLE (Zimmerman et al., 2006), which again allows us to study RFI as a factor in the palaeomagnetic recording process in

  11. Increased expression and dysregulated association of restriction factors and type I interferon in HIV, HCV mono- and co-infected patients.

    Zhu, Jia-Wu; Liu, Feng-Liang; Mu, Dan; Deng, De-Yao; Zheng, Yong-Tang


    Host restriction factors and type I interferon are important in limiting HIV and HCV infections, yet the role of HIV, HCV mono- and co-infection in regulating these antiviral genes expression is not clear. In this study, we measured the levels of TRIM5α, TRIM22, APOBEC3G, and IFN-α, -β mRNA expression in peripheral blood mononuclear cells of 43 HIV mono-infected, 70 HCV mono-infected and 64 HIV/HCV co-infected patients along with 98 healthy controls. We also quantified HIV and HCV viral loads in mono- and co-infected patients. The results showed that HCV, HIV mono- and co-infection differentially increased TRIM22, APOBEC3G, and IFN-α, -β mRNA expression while the mRNA expression of TRIMα was upregulated only by HCV-mono infection. HIV/HCV co-infection was associated with higher viral load, compared to either HIV or HCV mono-infection. Additionally, we showed TRIMα and TRIM22 positively correlated with IFN-α, -β, which could be dysregulated by HIV, HCV mono- and co-infection. Furthermore, we found TRIM22 negatively correlated with HCV viral load in mono-infected patients and APOBEC3G positively correlated with HCV viral load in co-infected patients. Collectively, our findings suggest the potential role of restriction factors in restricting HIV, HCV mono- and co-infection in vivo, which appears to be a therapeutic target for potential drug discovery.

  12. Viruses in Antarctic lakes

    Kepner, R. L. Jr; Wharton, R. A. Jr; Suttle, C. A.; Wharton RA, J. r. (Principal Investigator)


    Water samples collected from four perennially ice-covered Antarctic lakes during the austral summer of 1996-1997 contained high densities of extracellular viruses. Many of these viruses were found to be morphologically similar to double-stranded DNA viruses that are known to infect algae and protozoa. These constitute the first observations of viruses in perennially ice-covered polar lakes. The abundance of planktonic viruses and data suggesting substantial production potential (relative to bacteria] secondary and photosynthetic primary production) indicate that viral lysis may be a major factor in the regulation of microbial populations in these extreme environments. Furthermore, we suggest that Antarctic lakes may be a reservoir of previously undescribed viruses that possess novel biological and biochemical characteristics.

  13. Hypnosis, suggestion, and suggestibility: an integrative model.

    Lynn, Steven Jay; Laurence, Jean-Roch; Kirsch, Irving


    This article elucidates an integrative model of hypnosis that integrates social, cultural, cognitive, and neurophysiological variables at play both in and out of hypnosis and considers their dynamic interaction as determinants of the multifaceted experience of hypnosis. The roles of these variables are examined in the induction and suggestion stages of hypnosis, including how they are related to the experience of involuntariness, one of the hallmarks of hypnosis. It is suggested that studies of the modification of hypnotic suggestibility; cognitive flexibility; response sets and expectancies; the default-mode network; and the search for the neurophysiological correlates of hypnosis, more broadly, in conjunction with research on social psychological variables, hold much promise to further understanding of hypnosis.

  14. Effects of lake trout refuges on lake whitefish and cisco in the Apostle Islands Region of Lake Superior

    Zuccarino-Crowe , Chiara M.; Taylor, William W.; Hansen, Michael J.; Seider, Michael J.; Krueger, Charles C.


    Lake trout refuges in the Apostle Islands region of Lake Superior are analogous to the concept of marine protected areas. These refuges, established specifically for lake trout (Salvelinus namaycush) and closed to most forms of recreational and commercial fishing, were implicated as one of several management actions leading to successful rehabilitation of Lake Superior lake trout. To investigate the potential significance of Gull Island Shoal and Devils Island Shoal refuges for populations of not only lake trout but also other fish species, relative abundances of lake trout, lake whitefish (Coregonus clupeaformis), and cisco (Coregonus artedi) were compared between areas sampled inside versus outside of refuge boundaries. During 1982–2010, lake trout relative abundance was higher and increased faster inside the refuges, where lake trout fishing was prohibited, than outside the refuges. Over the same period, lake whitefish relative abundance increased faster inside than outside the refuges. Both evaluations provided clear evidence that refuges protected these species. In contrast, trends in relative abundance of cisco, a prey item of lake trout, did not differ significantly between areas inside and outside the refuges. This result did not suggest indirect or cascading refuge effects due to changes in predator levels. Overall, this study highlights the potential of species-specific refuges to benefit other fish species beyond those that were the refuges' original target. Improved understanding of refuge effects on multiple species of Great Lakes fishes can be valuable for developing rationales for refuge establishment and predicting associated fish community-level effects.

  15. Professional Android Programming with Mono for Android and NETC#

    McClure, Wallace B; Croft, John J; Dick, Jonathan; Hardy, Chris


    A one-of-a-kind book on Android application development with Mono for Android The wait is over! For the millions of .NET/C# developers who have been eagerly awaiting the book that will guide them through the white-hot field of Android application programming, this is the book. As the first guide to focus on Mono for Android, this must-have resource dives into writing applications against Mono with C# and compiling executables that run on the Android family of devices. Putting the proven Wrox Professional format into practice, the authors provide you with the knowledge you need to become a succ

  16. Playa Lakes

    Kansas Data Access and Support Center — This digital dataset provides information about the spatial distribution of soil units associated with playa lakes. Specific soil types have been designated by the...

  17. Greater Sage-grouse Telemetry - Mono Co. [ds68

    California Department of Resources — Combined telemetry locations for sage grouse in Mono County which were fitted with radio-transmitters for the USGS Greater sage-grouse project. Contains spatial and...

  18. Delineation of sympatric morphotypes of lake trout in Lake Superior

    Moore, Seth A.; Bronte, Charles R.


    Three morphotypes of lake trout Salvelinus namaycush are recognized in Lake Superior: lean, siscowet, and humper. Absolute morphotype assignment can be difficult. We used a size-free, whole-body morphometric analysis (truss protocol) to determine whether differences in body shape existed among lake trout morphotypes. Our results showed discrimination where traditional morphometric characters and meristic measurements failed to detect differences. Principal components analysis revealed some separation of all three morphotypes based on head and caudal peduncle shape, but it also indicated considerable overlap in score values. Humper lake trout have smaller caudal peduncle widths to head length and depth characters than do lean or siscowet lake trout. Lean lake trout had larger head measures to caudal widths, whereas siscowet had higher caudal peduncle to head measures. Backward stepwise discriminant function analysis retained two head measures, three midbody measures, and four caudal peduncle measures; correct classification rates when using these variables were 83% for leans, 80% for siscowets, and 83% for humpers, which suggests the measures we used for initial classification were consistent. Although clear ecological reasons for these differences are not readily apparent, patterns in misclassification rates may be consistent with evolutionary hypotheses for lake trout within the Laurentian Great Lakes.

  19. Genetic diversity of lake whitefish in lakes Michigan and Huron: sampling, standardization, and research priorities

    Stott, Wendylee; VanDeHey, Justin A.; Sloss, Brian L.


    We combined data from two laboratories to increase the spatial extent of a genetic data set for lake whitefish Coregonus clupeaformis from lakes Huron and Michigan and saw that genetic diversity was greatest between lakes, but that there was also structuring within lakes. Low diversity among stocks may be a reflection of relatively recent colonization of the Great Lakes, but other factors such as recent population fluctuation and localized stresses such as lamprey predation or heavy exploitation may also have a homogenizing effect. Our data suggested that there is asymmetrical movement of lake whitefish between Lake Huron and Lake Michigan; more genotypes associated with Lake Michigan were observed in Lake Huron. Adding additional collections to the calibrated set will allow further examination of diversity in other Great Lakes, answer questions regarding movement among lakes, and estimate contributions of stocks to commercial yields. As the picture of genetic diversity and population structure of lake whitefish in the Great Lakes region emerges, we need to develop methods to combine data types to help identify important areas for biodiversity and thus conservation. Adding genetic data to existing models will increase the precision of predictions of the impacts of new stresses and changes in existing pressures on an ecologically and commercially important species.

  20. Imaging the magmatic system of Mono Basin, California with magnetotellurics in three--dimensions

    Peacock, Jared R.; Mangan, Margaret T.; McPhee, Darcy K.; Ponce, David A.


    A three–dimensional (3D) electrical resistivity model of Mono Basin in eastern California unveils a complex subsurface filled with zones of partial melt, fluid–filled fracture networks, cold plutons, and regional faults. In 2013, 62 broadband magnetotelluric (MT) stations were collected in an array around southeastern Mono Basin from which a 3D electrical resistivity model was created with a resolvable depth of 35 km. Multiple robust electrical resistivity features were found that correlate with existing geophysical observations. The most robust features are two 300 ± 50 km3 near-vertical conductive bodies (3–10 Ω·m) that underlie the southeast and north-eastern margin of Mono Craters below 10 km depth. These features are interpreted as magmatic crystal–melt mush zones of 15 ± 5% interstitial melt surrounded by hydrothermal fluids and are likely sources for Holocene eruptions. Two conductive east–dipping structures appear to connect each magma source region to the surface. A conductive arc–like structure (< 0.9 Ω·m) links the northernmost mush column at 10 km depth to just below vents near Panum Crater, where the high conductivity suggests the presence of hydrothermal fluids. The connection from the southernmost mush column at 10 km depth to below South Coulée is less obvious with higher resistivity (200 Ω·m) suggestive of a cooled connection. A third, less constrained conductive feature (4–10 Ω·m) 15 km deep extending to 35 km is located west of Mono Craters near the eastern front of the Sierra Nevada escarpment, and is coincident with a zone of sporadic, long–period earthquakes that are characteristic of a fluid-filled (magmatic or metamorphic) fracture network. A resistive feature (103–105 Ω·m) located under Aeolian Buttes contains a deep root down to 25 km. The eastern edge of this resistor appears to structurally control the arcuate shape of Mono Craters. These observations have been combined to form a new conceptual model

  1. New mono-organotin (IV) dithiocarbamate complexes

    Muthalib, Amirah Faizah Abdul; Baba, Ibrahim


    Eighteen new mono-organotin dithiocarbamate compounds derived each nine from methyltin(IV) and phenyltin(IV) reacted using in-situ method with various type of N-dialkylamine together with carbon disulphide with the ratio of 1:3:3. Elemental and gravimetric analysis showed that the general formula of these compounds were RSnCl[S2CNR'R″]2 (R= Ph, CH3, R' = CH3, C2H5, C7H7 and R″ = C2H5, C6H11, iC3H7, C7H7). These compounds had been characterized by infrared spectroscopy, ultraviolet spectroscopy, 1H, 13C NMR spectroscopy and single crystal X-ray crystallography. The infrared spectra of these compounds showed three important peaks indicating the formation of dithiocarbamate compounds, ν(CN), ν(CS) and ν(Sn-S) band which present in the region of 1444-1519, 954-1098 and 318-349 cm-1 respectively. The ultraviolet-visible spectra showed an absorption band for the π - π* transition of NCS group in the range of 253 - 259 nm due to the intramolecular charge transfer of the ligand. The 13C NMR spectra showed an important shift for δ(N13CS2) in the range of 196.8 - 201.9 ppm.. Single crystal X-ray diffraction studies showed three new structures with the general formula of PhSnCl[S2CN(Et)(i-Pr)]2, MeSnCl[S2CN(Me)(Cy)]2 and MeSnCl[S2CN(i-Pr)(CH2Ph)]2. All structures having a distorted octahedral geometry set by CClS4 donor atom from the two chelating dithiocarbamate ligands.

  2. Mono-colonization with Lactobacillus acidophilus NCFM affects the intestinal metabolome as compared to germ-free mice

    Roager, Henrik Munch; Sulek, Karolina; Skov, Kasper

    of colonizing bacteria. In this study the effect of the Lactobacillus acidophilus NCFM strain was investigated by comparing the metabolome of mono-colonized and germ-free mice in several compartments. By liquid-chromatography coupled to mass spectrometry, we were able to show that the metabolome differed...... between the mono-colonized and germ-free mice, not only in ileum, caecum and colon, but also in plasma and liver. These observations suggest that L. acidophilus NCFM highly influence the metabolism in multiple compartments, underlying that the gut microbiota metabolism affects the host systemic metabolism....

  3. Geographical ancestry of Lake Malawi's cichlid fish diversity

    Genner, Martin J; Ngatunga, Benjamin P.; Mzighani, Semvua; Smith, Alan; Turner, George F


    The Lake Malawi haplochromine cichlid flock is one of the largest vertebrate adaptive radiations. The geographical source of the radiation has been assumed to be rivers to the south and east of Lake Malawi, where extant representatives of the flock are now present. Here, we provide mitochondrial DNA evidence suggesting the sister taxon to the Lake Malawi radiation is within the Great Ruaha river in Tanzania, north of Lake Malawi. Estimates of the time of divergence between the Lake Malawi flo...

  4. Estimating the volume of Alpine glacial lakes

    Cook, S. J.; Quincey, D. J.


    Supraglacial, moraine-dammed and ice-dammed lakes represent a potential glacial lake outburst flood (GLOF) threat to downstream communities in many mountain regions. This has motivated the development of empirical relationships to predict lake volume given a measurement of lake surface area obtained from satellite imagery. Such relationships are based on the notion that lake depth, area and volume scale predictably. We critically evaluate the performance of these existing empirical relationships by examining a global database of glacial lake depths, areas and volumes. Results show that lake area and depth are not always well correlated (r2 = 0.38) and that although lake volume and area are well correlated (r2 = 0.91), and indeed are auto-correlated, there are distinct outliers in the data set. These outliers represent situations where it may not be appropriate to apply existing empirical relationships to predict lake volume and include growing supraglacial lakes, glaciers that recede into basins with complex overdeepened morphologies or that have been deepened by intense erosion and lakes formed where glaciers advance across and block a main trunk valley. We use the compiled data set to develop a conceptual model of how the volumes of supraglacial ponds and lakes, moraine-dammed lakes and ice-dammed lakes should be expected to evolve with increasing area. Although a large amount of bathymetric data exist for moraine-dammed and ice-dammed lakes, we suggest that further measurements of growing supraglacial ponds and lakes are needed to better understand their development.

  5. Novel monofunctional platinum (II) complex Mono-Pt induces apoptosis-independent autophagic cell death in human ovarian carcinoma cells, distinct from cisplatin.

    Guo, Wen-Jie; Zhang, Yang-Miao; Zhang, Li; Huang, Bin; Tao, Fei-Fei; Chen, Wei; Guo, Zi-Jian; Xu, Qiang; Sun, Yang


    Failure to engage apoptosis appears to be a leading mechanism of resistance to traditional platinum drugs in patients with ovarian cancer. Therefore, an alternative strategy to induce cell death is needed for the chemotherapy of this apoptosis-resistant cancer. Here we report that autophagic cell death, distinct from cisplatin-induced apoptosis, is triggered by a novel monofunctional platinum (II) complex named Mono-Pt in human ovarian carcinoma cells. Mono-Pt-induced cell death has the following features: cytoplasmic vacuolation, caspase-independent, no nuclear fragmentation or chromatin condensation, and no apoptotic bodies. These characteristics integrally indicated that Mono-Pt, rather than cisplatin, initiated a nonapoptotic cell death in Caov-3 ovarian carcinoma cells. Furthermore, incubation of the cells with Mono-Pt but not with cisplatin produced an increasing punctate distribution of microtubule-associated protein 1 light chain 3 (LC3), and an increasing ratio of LC3-II to LC3-I. Mono-Pt also caused the formation of autophagic vacuoles as revealed by monodansylcadaverine staining and transmission electron microscopy. In addition, Mono-Pt-induced cell death was significantly inhibited by the knockdown of either BECN1 or ATG7 gene expression, or by autophagy inhibitors 3-methyladenine, chloroquine and bafilomycin A 1. Moreover, the effect of Mono-Pt involved the AKT1-MTOR-RPS6KB1 pathway and MAPK1 (ERK2)/MAPK3 (ERK1) signaling, since the MTOR inhibitor rapamycin increased, while the MAPK1/3 inhibitor U0126 decreased Mono-Pt-induced autophagic cell death. Taken together, our results suggest that Mono-Pt exerts anticancer effect via autophagic cell death in apoptosis-resistant ovarian cancer. These findings lead to increased options for anticancer platinum drugs to induce cell death in cancer.

  6. Thiamine concentrations in lake whitefish eggs from the upper Great Lakes are related to maternal diet

    Riley, S.C.; Rinchard, J.; Ebener, M.P.; Tillitt, D.E.; Munkittrick, K.R.; Parrott, J.L.; Allen, J.D.


    Thiamine deficiency is responsible for reproductive impairment in several species of salmonines in the Great lakes, and is thought to be caused by the consumption of prey containing thiaminase, a thiamine-degrading enzyme. Because thiaminase levels are extremely high in dreissenid mussels, fish that prey on them may be susceptible to thiamine deficiency. We determined thiamine concentrations in lake whitefish Coregonus clupeaformis eggs from the upper Laurentian Great Lakes to assess the potential for thiamine deficiency and to determine if thiamine concentrations in lake whitefish eggs were related to maternal diet. Mean thiamine concentrations in lake whitefish eggs were highest in Lake Huron, intermediate in Lake Superior, and lowest in Lake Michigan. Some fish had thiamine concentrations below putative thresholds for lethal and sublethal effects in salmonines, suggesting that some larval lake whitefish may currently be at risk of at least sublethal effects of low thiamine concentrations, although thiamine thresholds are unknown for lake whitefish. Egg thiamine concentrations in lake whitefish eggs were statistically significantly related to isotopic carbon signatures, suggesting that egg thiamine levels were related to maternal diet, but low egg thiamine concentrations did not appear to be associated with a diet of dreissenids. Egg thiamine concentrations were not statistically significantly related to multifunction oxidase induction, suggesting that lower egg thiamine concentrations in lake whitefish were not related to contaminant exposure.

  7. New mono-organotin (IV) dithiocarbamate complexes

    Muthalib, Amirah Faizah Abdul; Baba, Ibrahim [School of Chemical Sciences and Food Technology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi (Malaysia)


    Eighteen new mono-organotin dithiocarbamate compounds derived each nine from methyltin(IV) and phenyltin(IV) reacted using in-situ method with various type of N-dialkylamine together with carbon disulphide with the ratio of 1:3:3. Elemental and gravimetric analysis showed that the general formula of these compounds were RSnCl[S{sub 2}CNR′R″]{sub 2} (R= Ph, CH{sub 3}, R′ = CH{sub 3}, C{sub 2}H{sub 5}, C{sub 7}H{sub 7} and R″ = C{sub 2}H{sub 5}, C{sub 6}H{sub 11}, iC{sub 3}H{sub 7}, C{sub 7}H{sub 7}). These compounds had been characterized by infrared spectroscopy, ultraviolet spectroscopy, {sup 1}H, {sup 13}C NMR spectroscopy and single crystal X-ray crystallography. The infrared spectra of these compounds showed three important peaks indicating the formation of dithiocarbamate compounds, ν(CN), ν(CS) and ν(Sn-S) band which present in the region of 1444–1519, 954–1098 and 318–349 cm{sup −1} respectively. The ultraviolet-visible spectra showed an absorption band for the π - π* transition of NCS group in the range of 253 – 259 nm due to the intramolecular charge transfer of the ligand. The {sup 13}C NMR spectra showed an important shift for δ(N{sup 13}CS{sub 2}) in the range of 196.8 – 201.9 ppm.. Single crystal X-ray diffraction studies showed three new structures with the general formula of PhSnCl[S{sub 2}CN(Et)(i−Pr)]{sub 2}, MeSnCl[S{sub 2}CN(Me)(Cy)]{sub 2} and MeSnCl[S{sub 2}CN(i−Pr)(CH{sub 2}Ph)]{sub 2}. All structures having a distorted octahedral geometry set by CClS{sub 4} donor atom from the two

  8. The organic content of the Tagish Lake meteorite.

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


    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.

  9. Zooplankton communities in a large prealpine lake, Lake Constance: comparison between the Upper and the Lower Lake

    Gerhard MAIER


    Full Text Available The zooplankton communities of two basins of a large lake, Lake Constance, were compared during the years 2002 and 2003. The two basins differ in morphology, physical and chemical conditions. The Upper Lake basin has a surface area of 470 km2, a mean depth of 100 and a maximum depth of 250 m; the Lower Lake basin has a surface area of 62 km2, a mean depth of only 13 and a maximum depth of 40 m. Nutrient, chlorophyll-a concentrations and mean temperatures are somewhat higher in the Lower than in the Upper Lake. Total abundance of rotifers (number per m2 lake surface was higher and rotifer development started earlier in the year in the Lower than in the Upper Lake. Total abundance of crustaceans was higher in the Upper Lake in the year 2002; in the year 2003 no difference in abundance could be detected between the lake basins, although in summer crustacean abundance was higher in the Lower than in the Upper Lake. Crustacean communities differed significantly between lake basins while there was no apparent difference in rotifer communities. In the Lower Lake small crustaceans, like Bosmina spp., Ceriodaphnia pulchella and Thermocyclops oithonoides prevailed. Abundance (number per m2 lake surface of predatory cladocerans, large daphnids and large copepods was much lower in the Lower than in the Upper Lake, in particular during the summer months. Ordination with nonmetric multidimensional scaling (NMS separated communities of both lakes along gradients that correlated with temperature and chlorophyll a concentration. Clutches of copepods were larger in the Lower than in the Upper Lake. No difference could be detected in clutch size of large daphnids between lake basins. Our results show that zooplankton communities in different basins of Lake Constance can be very different. They further suggest that the lack of large crustaceans in particular the lack of large predatory cladocerans in the Lower Lake can have negative effects on growth and

  10. Theories of Suggestion.

    Brown, W


    The word "suggestion" has been used in educational, scientific and medical literature in slightly different senses. In psychological medicine the use of suggestion has developed out of the earlier use of hypnotic influence.Charcot defined hypnosis as an artificial hysteria, Bernheim as an artificially increased suggestibility. The two definitions need to be combined to give an adequate account of hypnosis. Moreover, due allowance should be made for the factors of dissociation and of rapport in hypnotic phenomena.The relationships between dissociation, suggestibility, and hypnotizability.Theories of suggestion propounded by Pierre Janet, Freud, McDougall, Pawlow and others. Ernest Jones's theory of the nature of auto-suggestion. Janet explains suggestion in terms of ideo-motor action in which the suggested idea, because of the inactivity of competing ideas, produces its maximum effect. Freud explains rapport in terms of the sex instinct "inhibited in its aim" (transference) and brings in his distinction of "ego" and "ego-ideal" (or "super-ego") to supplement the theory. Jones explains auto-suggestion in terms of narcissism. McDougall explains hypnotic suggestion in terms of the instinct of self-abasement. But different instincts may supply the driving power to produce suggestion-effects in different circumstances. Such instincts as those of self-preservation (fear) and gregariousness may play their part. Auto-suggestion as a therapeutic factor is badly named. It supplements, but does not supplant the will, and makes complete volition possible.

  11. Pairing preferences of the model mono-valence mono-atomic ions investigated by molecular simulation.

    Zhang, Qiang; Zhang, Ruiting; Zhao, Ying; Li, HuanHuan; Gao, Yi Qin; Zhuang, Wei


    We carried out a series of potential of mean force calculations to study the pairing preferences of a series of model mono-atomic 1:1 ions with evenly varied sizes. The probabilities of forming the contact ion pair (CIP) and the single water separate ion pair (SIP) were presented in the two-dimensional plots with respect to the ion sizes. The pairing preferences reflected in these plots largely agree with the empirical rule of matching ion sizes in the small and big size regions. In the region that the ion sizes are close to the size of the water molecule; however, a significant deviation from this conventional rule is observed. Our further analysis indicated that this deviation originates from the competition between CIP and the water bridging SIP state. The competition is mainly an enthalpy modulated phenomenon in which the existing of the water bridging plays a significant role.

  12. Great Lakes

    Edsall, Thomas A.; Mac, Michael J.; Opler, Paul A.; Puckett Haecker, Catherine E.; Doran, Peter D.


    The Great Lakes region, as defined here, includes the Great Lakes and their drainage basins in Minnesota, Wisconsin, Illinois, Indiana, Ohio, Pennsylvania, and New York. The region also includes the portions of Minnesota, Wisconsin, and the 21 northernmost counties of Illinois that lie in the Mississippi River drainage basin, outside the floodplain of the river. The region spans about 9º of latitude and 20º of longitude and lies roughly halfway between the equator and the North Pole in a lowland corridor that extends from the Gulf of Mexico to the Arctic Ocean.The Great Lakes are the most prominent natural feature of the region (Fig. 1). They have a combined surface area of about 245,000 square kilometers and are among the largest, deepest lakes in the world. They are the largest single aggregation of fresh water on the planet (excluding the polar ice caps) and are the only glacial feature on Earth visible from the surface of the moon (The Nature Conservancy 1994a).The Great Lakes moderate the region’s climate, which presently ranges from subarctic in the north to humid continental warm in the south (Fig. 2), reflecting the movement of major weather masses from the north and south (U.S. Department of the Interior 1970; Eichenlaub 1979). The lakes act as heat sinks in summer and heat sources in winter and are major reservoirs that help humidify much of the region. They also create local precipitation belts in areas where air masses are pushed across the lakes by prevailing winds, pick up moisture from the lake surface, and then drop that moisture over land on the other side of the lake. The mean annual frost-free period—a general measure of the growing-season length for plants and some cold-blooded animals—varies from 60 days at higher elevations in the north to 160 days in lakeshore areas in the south. The climate influences the general distribution of wild plants and animals in the region and also influences the activities and distribution of the human

  13. Degenerate gaugino mass region and mono-boson collider signatures

    Anandakrishnan, Archana; Raby, Stuart


    In this paper we discuss search strategies at the LHC for light electroweak gauginos which are mostly Wino-like, Higgsino-like or an admixture. These states are typically degenerate with decay products that are less energetic and hence difficult to detect. In addition, their production cross-sections at a hadron collider are suppressed compared to colored states such as the gluinos. In order to detect these states one needs to trigger on initial or final state radiation. Many previous analyses have focussed on mono-jet and mono-photon triggers. In the paper we argue and show that these triggers are unlikely to succeed, due to the large background from QCD backgrounds for the mono-jet searches and the fact that the $p_T$ distribution of the mono-photons are rapidly decreasing functions of $p_T$. We show this with both an analytic calculation of photons in the initial state radiation and also a detailed numerical analysis. We then argue that mono-Z triggers, from Z decaying into charged leptons may well provide...

  14. Suggested safeguards an

    MJM Venter

    ... COORDINATION. (FACILITATION OR CASE MANAGEMENT) IN SOUTH AFRICA ... SUGGESTED SAFEGUARDS AND LIMITATIONS FOR EFFECTIVE AND .... professional practice.27 They have to assess the situation; educate the parents.

  15. Taxa-specific eco-sensitivity in relation to phytoplankton bloom stability and ecologically relevant lake state

    Napiórkowska-Krzebietke, Agnieszka; Dunalska, Julita A.; Zębek, Elżbieta


    Phytoplankton (including plant-like, animal-like algae and Cyanobacteria) blooms have recently become a serious global threat to the sustenance of ecosystems, to human and animal health and to economy. This study focused on the composition and stability of blooms as well as their taxa-specific ecological sensitivity to the main causal factors (especially phosphorus and nitrogen) in degraded urban lakes. The analyzed lakes were assessed with respect to the trophic state as well as ecological status. Total phytoplankton biomass (ranging from 1.5 to 181.3 mg dm-3) was typical of blooms of different intensity, which can appear during a whole growing season but are the most severe in early or late summer. Our results suggested that steady-state and non-steady-state bloom assemblages including mono-, bi- and multi-species or heterogeneous blooms may occur in urban lakes. The most intense blooms were formed by the genera of Cyanobacteria: Microcystis, Limnothrix, Pseudanabaena, Planktothrix, Bacillariophyta: Cyclotella and Dinophyta mainly Ceratium and Peridinium. Considering the sensitivity of phytoplankton assemblages, a new eco-sensitivity factor was proposed (E-SF), based on the concept of Phytoplankton Trophic Index composed of trophic scores of phytoplankton taxa along the eutrophication gradient. The E-SF values of 0.5, 1.3, 6.7 and 15.1 were recognized in lakes having a high, good, moderate or poor ecological status, respectively. For lake restoration, each type of bloom should be considered separately because of different sensitivities of taxa and relationships with environmental variables. Proper recognition of the taxa-specific response to abiotic (especially to N and P enrichment) and biotic factors could have significant implications for further water protection and management.

  16. Manufacturer's Suggested Retail Prices

    Rosenkranz, S.


    Based on arguments of the `reference- dependent' theory of consumer choice we assume that a retailer's discount of a manufacturer's suggested retail price changes consumers' demand. We can show that the producer benefits from suggesting a retail price. If consumers are additionally sufficiently `los

  17. Mono-hydroxy methoxychlor alters levels of key sex steroids and steroidogenic enzymes in cultured mouse antral follicles.

    Craig, Zelieann R; Leslie, Traci C; Hatfield, Kimberly P; Gupta, Rupesh K; Flaws, Jodi A


    Methoxychlor (MXC) is an organochlorine pesticide that reduces fertility in female rodents by decreasing antral follicle numbers and increasing follicular death. MXC is metabolized in the body to mono-hydroxy MXC (mono-OH). Little is known about the effects of mono-OH on the ovary. Thus, this work tested the hypothesis that mono-OH exposure decreases production of 17β-estradiol (E₂) by cultured mouse antral follicles. Antral follicles were isolated from CD-1 mice (age 35-39 days) and exposed to dimethylsulfoxide (DMSO), or mono-OH (0.1-10 μg/mL) for 96 h. Media and follicles were collected for analysis of sex steroid levels and mRNA expression, respectively. Mono-OH treatment (10 μg/mL) decreased E(2) (DMSO: 3009.72±744.99 ng/mL; mono-OH 0.1 μg/mL: 1679.66±461.99 ng/mL; 1 μg/mL: 1752.72±532.41 ng/mL; 10 μg/mL: 45.89±33.83 ng/mL), testosterone (DMSO: 15.43±2.86 ng/mL; mono-OH 0.1μg/mL: 17.17±4.71 ng/mL; 1 μg/mL: 13.64±3.53 ng/mL; 10 μg/mL: 1.29±0.23 ng/mL), androstenedione (DMSO: 1.92±0.34 ng/mL; mono-OH 0.1 μg/mL: 1.49±0.43ng/mL; 1 μg/mL: 0.64±0.31 ng/mL; 10 μg/mL: 0.12±0.06 ng/mL) and progesterone (DMSO: 24.11±4.21 ng/mL; mono-OH 0.1μg/mL: 26.77±4.41 ng/mL; 1 μg/mL: 20.90±3.75 ng/mL; 10 μg/mL: 9.44±2.97 ng/mL) levels. Mono-OH did not alter expression of Star, Hsd3b1, Hsd17b1 and Cyp1b1, but it did reduce levels of Cyp11a1, Cyp17a1 and Cyp19a1 mRNA. Collectively, these data suggest that mono-OH significantly decreases levels of key sex steroid hormones and the expression of enzymes required for steroidogenesis.

  18. Possible temperate lakes on Titan

    Vixie, Graham; Barnes, Jason W.; Jackson, Brian; Rodriguez, Sébastien; Le Mouélic, Stéphane; Sotin, Christophe; MacKenzie, Shannon; Wilson, Paul


    We analyze southern mid-latitude albedo-dark features on Titan observed by Cassini's Visual and Infrared Mapping Spectrometer (VIMS). In exploring the nature of these features we consider their morphology, albedo, and specular reflectivity. We suggest that they represent candidates for potential temperate lakes. The presence of lakes at the mid-latitudes would indicate that surface liquid can accumulate and remain stable away from Titan's poles. Candidate lakes were identified by looking for possible shorelines with lacustrine morphology. Then, we applied an atmospheric correction that empirically solved for their surface albedo. Finally, we looked for a specular reflection of the sky in the identified candidates. Using this prescription, we find two candidates that remain as potential temperature lakes. If candidate features do represent temperate lakes on Titan, they have implications for formation mechanisms such as clouds and rainfall or, in low elevation areas, percolation and subsurface flow. Clouds were observed near candidate lake locations on the T66 flyby and this latitude band showed many clouds during southern summer. Our techniques can be applied to areas of Titan that lack RADAR coverage to search for mid- and low-latitude lakes in the future.

  19. Fatigue Analysis of a Mono-Tower Platform

    Kirkegaard, Poul Henning; Sørensen, John Dalsgaard; Brincker, Rune

    In this paper, a fatigue reliability analysis of a Mono-tower platform is presented. The failure mode, fatigue failure in the butt welds, is investigated with two different models. The one with the fatigue strength expressed through SN relations, the other with the fatigue strength expressed thro...... of the natural period, damping ratio, current, stress Spectrum and parameters describing the fatigue strength. Further, soil damping is shown to be significant for the Mono-tower.......In this paper, a fatigue reliability analysis of a Mono-tower platform is presented. The failure mode, fatigue failure in the butt welds, is investigated with two different models. The one with the fatigue strength expressed through SN relations, the other with the fatigue strength expressed...

  20. Fatigue Reliability Analysis of a Mono-Tower Platform

    Kirkegaard, Poul Henning; Sørensen, John Dalsgaard; Brincker, Rune


    In this paper, a fatigue reliability analysis of a Mono-tower platform is presented. The failure mode, fatigue failure in the butt welds, is investigated with two different models. The one with the fatigue strength expressed through SN relations, the other with the fatigue strength expressed thro...... of the natural period, damping ratio, current, stress spectrum and parameters describing the fatigue strength. Further, soil damping is shown to be significant for the Mono-tower.......In this paper, a fatigue reliability analysis of a Mono-tower platform is presented. The failure mode, fatigue failure in the butt welds, is investigated with two different models. The one with the fatigue strength expressed through SN relations, the other with the fatigue strength expressed...

  1. Extraction of mono- and dicarboxylic acids from a curative water.

    Franke, C; Weil, L; Niessner, R


    A method for the analysis of mono- and dicarboxylic acids from water is presented. For this purpose two techniques, a C(18) solid phase extraction (SPE) and a combination method of liquid-liquid extraction (LLE) and aminopropyl SPE, were tested. With the combination method all analytes, short-chain mono- and long-chain dicarboxylic acids, could be analysed in one approach. The C(18) SPE was not suitable for short-chain mono- but for dicarboxylic acids. Concentrations in the investigated water ranged from 315 mg/l (butanoic acid) to 2.9 mg/l (octanoic acid). Dicarboxylic acids were found from 5 mg/l (octanedioic acid) to 0.5 mg/l (dodecanedioic acid).

  2. Research Suggestions for Students

    Holland, John L.


    Describes how to perform accurate research. Also includes suggestions for specific research projects under such headings as: (1) types; (2) environments; (3) interactions; (4) classification; (5) hexagonal model; and (6) differentiation. (HMV)

  3. Open to Suggestion.

    Journal of Reading, 1984


    Contributors offer suggestions concerning parents as reading stimulators, book discussions, a test bank for the secondary school/college reading lab, standardized reading tests, television reading, plagiarism, vocabulary development, and book reports. (FL)

  4. Open To Suggestion.

    Journal of Reading, 1988


    Suggests class activities in three short articles including: (1) "Students Evaluate Reading," by Lenore Sandel; (2) "Solving Verbal Analogies," by Edward J. Dwyer; and (3) "Becoming Testwise," by Dean Schoen. (RS)

  5. Reliability Analysis of a Mono-Tower Platform

    Kirkegaard, Poul Henning; Enevoldsen, I.; Sørensen, John Dalsgaard;

    In this paper a reliability analysis of a Mono-tower platform is presented. The failure modes, considered, are yelding in the tube cross-sections, and fatigue failure in the butt welds. The fatigue failure mode is investigated with a fatigue model, where the fatigue strength is expressed through SN...... for the fatigue limit state is a significant failure mode for the Mono.tower platform. Further, it is shown for the fatigue failure mode the the largest contributions to the overall uncertainty are due to the damping ratio, the inertia coefficient, the stress concentration factor, the model uncertainties...

  6. Reliability Analysis of a Mono-Tower Platform

    Kirkegaard, Poul Henning; Enevoldsen, I.; Sørensen, John Dalsgaard;


    In this paper, a reliability analysis of a Mono-tower platform is presented. Te failure modes considered are yielding in the tube cross sections and fatigue failure in the butts welds. The fatigue failrue mode is investigated with a fatigue model, where the fatigue strength is expressed through SN...... that the fatigue limit state is a significant failure mode for the Mono-tower platform. Further, it is shown for the fatigue failure mode that the largest contributions to the overall uncertainty are due to the damping ratio, the inertia coefficient, the stress concentration factor, the model uncertainties...

  7. Cost-Effective Mass Production of Mono Bucket Foundations

    Gres, Szymon; Nielsen, Søren Andreas; Fejerskov, Morten


    No recognized procedures exist for the Mono Bucket Foundation design, which is an obstruction for mass customization/production and industrialization in relation to certifying authorities. This paper presents the outcome of on-going research and development program that provides solution for inno......No recognized procedures exist for the Mono Bucket Foundation design, which is an obstruction for mass customization/production and industrialization in relation to certifying authorities. This paper presents the outcome of on-going research and development program that provides solution...

  8. Microplastics in Taihu Lake, China.

    Su, Lei; Xue, Yingang; Li, Lingyun; Yang, Dongqi; Kolandhasamy, Prabhu; Li, Daoji; Shi, Huahong


    In comparison with marine environments, the occurrence of microplastics in freshwater environments is less understood. In the present study, we investigated microplastic pollution levels during 2015 in Taihu Lake, the third largest Chinese lake located in one of the most developed areas of China. The abundance of microplastics reached 0.01 × 10(6)-6.8 × 10(6) items/km(2) in plankton net samples, 3.4-25.8 items/L in surface water, 11.0-234.6 items/kg dw in sediments and 0.2-12.5 items/g ww in Asian clams (Corbicula fluminea). The average abundance of microplastics was the highest in plankton net samples from the southeast area of the lake and in the sediments from the northwest area of the lake. The northwest area of the lake was the most heavily contaminated area of the lake, as indicated by chlorophyll-α and total phosphorus. The microplastics were dominated by fiber, 100-1000 μm in size and cellophane in composition. To our best knowledge, the microplastic levels measured in plankton net samples collected from Taihu Lake were the highest found in freshwater lakes worldwide. The ratio of the microplastics in clams to each sediment sample ranged from 38 to 3810 and was negatively correlated to the microplastic level in sediments. In brief, our results strongly suggest that high levels of microplastics occurred not only in water but also in organisms in Taihu Lake.

  9. Discovery and industrial applications of lytic polysaccharide mono-oxygenases.

    Johansen, Katja S


    The recent discovery of copper-dependent lytic polysaccharide mono-oxygenases (LPMOs) has opened up a vast area of research covering several fields of application. The biotech company Novozymes A/S holds patents on the use of these enzymes for the conversion of steam-pre-treated plant residues such as straw to free sugars. These patents predate the correct classification of LPMOs and the striking synergistic effect of fungal LPMOs when combined with canonical cellulases was discovered when fractions of fungal secretomes were evaluated in industrially relevant enzyme performance assays. Today, LPMOs are a central component in the Cellic CTec enzyme products which are used in several large-scale plants for the industrial production of lignocellulosic ethanol. LPMOs are characterized by an N-terminal histidine residue which, together with an internal histidine and a tyrosine residue, co-ordinates a single copper atom in a so-called histidine brace. The mechanism by which oxygen binds to the reduced copper atom has been reported and the general mechanism of copper-oxygen-mediated activation of carbon is being investigated in the light of these discoveries. LPMOs are widespread in both the fungal and the bacterial kingdoms, although the range of action of these enzymes remains to be elucidated. However, based on the high abundance of LPMOs expressed by microbes involved in the decomposition of organic matter, the importance of LPMOs in the natural carbon-cycle is predicted to be significant. In addition, it has been suggested that LPMOs play a role in the pathology of infectious diseases such as cholera and to thus be relevant in the field of medicine. © 2016 Authors; published by Portland Press Limited.

  10. Dust Storms From Owens and Mono Valleys, California


    asthma , and chronic bronchitis are subject to increased morbidity. Hospitalization of these patients with bronchial spasm and related pulmonary...waters in Lake Magadi, Kenya . at temperatures between 67 and 82’C and p11 about 9 (Eugster and Jones 1968. p. 160).The temperature in the first...Silicate, Lake Magadi, Kenya ." Science, Volume 161, 12 July 1968. Pp. 160-163. Eugster, H. P., and G. I. Smith. "Mineral Equilibria in the Searles Lake

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

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


    Acidic mining lakes (pH 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.

  12. Attitudes to Suggestions



    As an Australian expat teaching English in China for over four years, I often encourage my students to not only learn the English language but also try to understand Western culture. This includes the fact that Westerners frequently initiate proactive suggestions on any aspects of soci-

  13. Palaeolimnological evidence of vulnerability of Lake Neusiedl (Austria) toward climate related changes since the last "vanished-lake" stage.

    Tolotti, Monica; Milan, Manuela; Boscaini, Adriano; Soja, Gerhard; Herzig, Alois


    The palaeolimnological reconstruction of secular evolution of Euroepan Lakes with key socio-economical relevance respect to large (climate change) and local scale (land use, tourism) environmental changes, represents one of the objectives of the project EuLakes (European Lakes Under Environmental Stressors, Supporting lake governance to mitigate the impact of climate change, Reg. N. 2CE243P3), launched in 2010 within the Central European Inititiative. The project consortium comprises lakes of different morphology and prevalent human uses, including the meso-eutrophic Lake Neusiedl, the largest Austrian lake (total area 315 km2), and the westernmost shallow (mean depth 1.2 m) steppe lake of the Euro-Asiatic continent. The volume of Lake Neusiedl can potentially change over the years, in relation with changing balance between atmospheric precipitation and lake water evapotranspiration. Changing water budget, together with high lake salinity and turbidity, have important implications over the lake ecosystem. This contribution illustrates results of the multi-proxi palaeolimnological reconstruction of ecologial changes occurred in Lake Neusiedl during the last ca. 140 years, i.e. since the end of the last "vanished-lake" stage (1865-1871). Geochemical and biological proxies anticipate the increase in lake productivity of ca. 10 years (1950s) respect to what reported in the literature. Diatom species composition indicate a biological lake recovery in the late 1980s, and suggest a second increment in lake productivity since the late 1990s, possibly in relation with the progressive increase in the nitrogen input from agriculture. Abundance of diatoms typical of brackish waters indicated no significant long-term change in lake salinity, while variations in species toleranting dessiccation confirm the vulnerability of Lake Neusiedl toward climate-driven changes in the lake water balance. This fragility is aggravated by the the semi-arid climate conditions of the catchemnt

  14. Plasma etching on large-area mono-, multi- and quasi-mono crystalline silicon

    Davidsen, Rasmus Schmidt; Schmidt, Michael Stenbæk; Boisen, Anja


    We use plasma etched Black Si (BS)[1][2] nanostructures to achieve low reflectance due to the resulting graded refractive index at the Si-air interface. The goal of this investigation is to develop a suitable texturing method for Si solar cells. Branz et al. [3]report below 3% average reflectance...... for their 16.8% efficient black Si cell using a metal-assisted, chemical etching method on FZ mono-crystalline Si substrates. Yoo et al. [4] use RIE similar to this work on large-area, multi-crystalline Si cells and achieve a 16.1% efficiency despite a relatively high reflectance of 13.3%. Despite several...... advantages such as; (i) excellent light trapping, (ii) dry, single-sided and scalable process method and (iii) etch independence on crystallinity of Si, RIE-texturing has so far not been proven superior to standard wet texturing, primarily as a result of lower power conversion efficiency due to increased...

  15. Systemic lupus erythematosus patients contain significantly less igm against mono-methylated lysine than healthy subjects.

    Sha Guo

    Full Text Available Post-translational modifications on proteins are important in biological processes but may create neo-epitopes that induce autoimmune responses. In this study, we measured the serum IgG and IgM response to a set of non-modified or acetyl- and methyl-modified peptides corresponding to residues 1-19 of the histone 3 N-terminal tail in systemic lupus erythematosus (SLE patients and healthy subjects. Our results indicated that the SLE patients and healthy subjects produced antibodies (Abs to the peptides, but the two groups had different Ab isotype and epitope preferences. Abs to the non-modified form, H31-19, were of the IgG isotype and produced by SLE patients. They could not recognize the scrambled H31-19, which contained the same amino acid composition but a different sequence as H31-19. In comparison, healthy subjects in general did not produce IgG against H31-19. However, about 70% of the healthy subjects produced IgM Abs against mono-methylated K9 of H31-19 (H31-19K9me. Our further studies revealed that ε-amine mono-methylated lysine could completely inhibit the IgM binding to H31-19K9me, but lysine had no inhibitory effect. In addition, the IgM Abs could bind peptides containing a mono-methylated lysine residue but with totally different sequences. Thus, mono-methylated lysine was the sole epitope for the IgM. Interestingly, SLE patients had much lower levels of this type of IgM. There was no obvious correlation between the IgM levels and disease activity and the decreased IgM was unlikely caused by medical treatments.We also found that the IgM Abs were not polyreactive to dsDNA, ssDNA, lipopolysaccharide (LPS or insulin and they did not exist in umbilical cord serum, implying that they were not natural Abs. The IgM Abs against mono-methylated lysine are present in healthy subjects but are significantly lower in SLE patients, suggesting a distinct origin of production and special physiological functions.

  16. Bathymetry of Lake Michigan

    National Oceanic and Atmospheric Administration, Department of Commerce — Bathymetry of Lake Michigan has been compiled as a component of a NOAA project to rescue Great Lakes lake floor geological and geophysical data and make it more...

  17. Bathymetry of Lake Ontario

    National Oceanic and Atmospheric Administration, Department of Commerce — Bathymetry of Lake Ontario has been compiled as a component of a NOAA project to rescue Great Lakes lake floor geological and geophysical data and make it more...

  18. Designated Wildlife Lakes - points

    Minnesota Department of Natural Resources — This is a point shapefile of Designated Wildlife Lakes in Minnesota. This shapefile was created by converting lake polygons from the Designated Wildlife Lakes...

  19. Great Lakes Bathymetry

    National Oceanic and Atmospheric Administration, Department of Commerce — Bathymetry of Lakes Michigan, Erie, Saint Clair, Ontario and Huron has been compiled as a component of a NOAA project to rescue Great Lakes lake floor geological and...

  20. Bathymetry of Lake Superior

    National Oceanic and Atmospheric Administration, Department of Commerce — Bathymetry of Lake Superior has been compiled as a component of a NOAA project to rescue Great Lakes lake floor geological and geophysical data and make it more...

  1. Hydrography - Lakes Assessments - Attaining

    NSGIC GIS Inventory (aka Ramona) — This layer shows only attaining lakes of the Integrated List. The Lakes Integrated List represents lake assessments in an integrated format for the Clean Water Act...

  2. Bathymetry of Lake Huron

    National Oceanic and Atmospheric Administration, Department of Commerce — Bathymetry of Lake Huron has been compiled as a component of a NOAA project to rescue Great Lakes lake floor geological and geophysical data and make it more...

  3. Suggestions for Teaching Practice

    ZHAN Na-na


    Teacher development and teaching practice(TP) have caught the eyes of researchers at home and abroad for many years. Many western scholars hold that reflective teaching is an efficient way to promote teacher development, but traditional TP is prevailing in China. Based on the merits and demerits of traditional TP and reflective TP, the author hopes to provide some suggestions for the people involved to promote the development of teacher education.

  4. 21 CFR 184.1505 - Mono- and diglycerides.


    ... 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...

  5. Tagging a mono-top signature in Natural SUSY

    Goncalves, Dorival; Takeuchi, Michihisa


    We study the feasibility of probing a region of Natural Supersymmetry where the stop and higgsino masses are compressed. Although this region is most effectively searched for in the mono-jet channel, this signature is present in many other non-supersymmetric frameworks. Therefore, another channel that carries orthogonal information is required to confirm the existence of the light stop and higgsinos. We show that a supersymmetric version of the $t \\bar t H$ process, $pp \\to t \\tilde t_1 \\tilde \\chi^0_{1(2)}$, can have observably large rate when both the stop and higgsinos are significantly light, and it leads to a distinctive mono-top signature in the compressed mass region. We demonstrate that the hadronic channel of the mono-top signature can effectively discriminate the signal from backgrounds by tagging a hadronic top-jet. We show that the hadronic channel of mono-top signature offers a significant improvement over the leptonic channel and the sensitivity reaches $m_{\\tilde t_1} \\simeq 420$ GeV at the 13 ...

  6. Spin, Charge, and Bonding in Transition Metal Mono Silicides

    Marel, D. van der; Damascelli, A.; Schulte, K.; Menovsky, A. A.


    Published in: Physica B 244 (1998) 138-147 citations recorded in [Science Citation Index] Abstract: We review some of the relevant physical properties of the transition metal mono-silicides with the FeSi structure (CrSi, MnSi, FeSi, CoSi, NiSi, etc) and explore the relation between their structural

  7. IRIS Toxicological Review of Ethylene Glycol Mono Butyl ...

    EPA has finalized the Toxicological Review of Ethylene Glycol Mono Butyl Ether: in support of the Integrated Risk Information System (IRIS). Now final, this assessment may be used by EPA’s program and regional offices to inform decisions to protect human health. N/A

  8. Transient Monotonic and Cyclic Load Effects on Mono Bucket Foundations

    Nielsen, Søren Dam

    and when hitting the foundation they induce high impact loads with a short duration. It is important that the foundation is able to resists these huge loads. Fortunately, the conducted research showed that the capacity of the mono bucket foundation is high to impact loads. When exposed to a huge wave load...

  9. Temperature dependence of atomic vibrations in mono-layer graphene

    Allen, C.S.; Liberti, E.; Kim, J.S.; Xu, Q.; Fan, Y.; He, K.; Robertson, A.W.; Zandbergen, H.W.; Warner, J.H.; Kirkland, A.I.


    We have measured the mean square amplitude of both in- and out-of-plane lattice vibrations for mono-layer graphene at temperatures ranging from ∼100 K to 1300 K. The amplitude of lattice vibrations was calculated from data extracted from selected area electron diffraction patterns recorded across a

  10. Electricity generation by anaerobic bacteria and anoxic sediments from hypersaline soda lakes

    Miller, L.G.; Oremland, R.S.


    Anaerobic bacteria and anoxic sediments from soda lakes produced electricity in microbial fuel cells (MFCs). No electricity was generated in the absence of bacterial metabolism. Arsenate respiring bacteria isolated from moderately hypersaline Mono Lake (Bacillus selenitireducens), and salt-saturated Searles Lake, CA (strain SLAS-1) oxidized lactate using arsenate as the electron acceptor. However, these cultures grew equally well without added arsenate using the MFC anode as their electron acceptor, and in the process oxidized lactate more efficiently. The decrease in electricity generation by consumption of added alternative electron acceptors (i.e. arsenate) which competed with the anode for available electrons proved to be a useful indicator of microbial activity and hence life in the fuel cells. Shaken sediment slurries from these two lakes also generated electricity, with or without added lactate. Hydrogen added to sediment slurries was consumed but did not stimulate electricity production. Finally, electricity was generated in statically incubated "intact" sediment cores from these lakes. More power was produced in sediment from Mono Lake than from Searles Lake, however microbial fuel cells could detect low levels of metabolism operating under moderate and extreme conditions of salt stress. ?? 2008 US Government.

  11. Great Lakes Science Center

    Federal Laboratory Consortium — Since 1927, Great Lakes Science Center (GLSC) research has provided critical information for the sound management of Great Lakes fish populations and other important...

  12. Morphological variation of siscowet lake trout in Lake Superior

    Bronte, C.R.; Moore, S.A.


    Historically, Lake Superior has contained many morphologically distinct forms of the lake trout Salvelinus namaycush that have occupied specific depths and locations and spawned at specific times of the year. Today, as was probably the case historically, the siscowet morphotype is the most abundant. Recent interest in harvesting siscowets to extract oil containing omega-3 fatty acids will require additional knowledge of the biology and stock structure of these lightly exploited populations. The objective of this study was to determine whether shape differences exist among siscowet populations across Lake Superior and whether these shape differences can be used to infer stock structure. Morphometric analysis (truss protocol) was used to differentiate among siscowets sampled from 23 locations in Lake Superior. We analyzed 31 distance measurements among 14 anatomical landmarks taken from digital images of fish recorded in the field. Cluster analysis of size-corrected data separated fish into three geographic groups: The Isle Royale, eastern (Michigan), and western regions (Michigan). Finer scales of stock structure were also suggested. Discriminant function analysis demonstrated that head measurements contributed to most of the observed variation. Cross-validation classification rates indicated that 67–71% of individual fish were correctly classified to their region of capture. This is the first study to present shape differences associated with location within a lake trout morphotype in Lake Superior.

  13. Planning Interventions for Lake Conservation: A Case of Shahpura Lake, Bhopal, India

    Munoth, Navneet; Nagaich, Anugrah Anilkumar


    With due increment in the development process of India, the problems related to environment are under constant increment and its contamination has now became a great threat for the rich ecology of the country. Particularly, the problems regarding the water quality are now becoming more acute and complicated due to increasing urbanization, industrialization, siltation, agricultural run-off and discharge of untreated sewage water. The city Bhopal in India having named as the city of lakes, is also experiencing similar issues. The famous characteristic lakes of Bhopal are under great environmental stress due to pollution from various sources. The Shahpura lake is one such lake, situated well within the city. A number of wards and colonies surrounding the lake boundary discharge their sewage and silage into the existing drainage network of the area, which ultimately finds its way into the lake through open drains. The main source of contamination in the lake is sewage fed drains, which are dumped into the lake during the summers. Besides this, other activities like bathing, cloth washing, cattle bathing and religious activities like idol immersion etc. also paves the way for high concentration of harmful chemicals in the lake. This work mainly discusses the existing situation and causes of water pollution in the Shahpura lake of Bhopal. It also brings into light the constitutional safeguards related to Lake Conservation in India and reviews their practical implications. In the end, it focuses on recommending the lake conservation strategies for the case of Shahpura lake; and suggests measures that could be adopted elsewhere to prevent the issue of lake pollution from various sources, emphasizing the importance of lakes.

  14. Pyrogen testing of lipid-based TPN using Mono Mac 6 monocyte cell line and DELFIA

    Moesby, Lise; Hansen, E W; Christensen, J D


    Measurement of lipopolysaccharide (LPS) induced interleukin-6 (IL-6) secretion in Mono Mac 6 cells.......Measurement of lipopolysaccharide (LPS) induced interleukin-6 (IL-6) secretion in Mono Mac 6 cells....

  15. Mono Lake or Laschamp geomagnetic event recorded from lava flows in Amsterdam Island (southeastern Indian Ocean)

    Carvallo, C; Ruffet, G; Henry, B I; Poidras, T; Carvallo, Claire; Camps, Pierre; Ruffet, Gilles; Henry, Bernard; Proxy, Thierry Poidras


    We report a survey carried out on basalt flows from Amsterdam Island in order to check the presence of intermediate directions interpreted to belong to a geomagnetic field excursion within the Brunhes epoch, completing this paleomagnetic record with paleointensity determinations and radiometric dating. The directional results corroborate the findings by Watkins and Nougier (1973) : normal polarity is found for two units and an intermediate direction, with associated VGPs close to the equator, for the other two units. A notable result is that these volcanic rocks are well suited for absolute paleointensity determinations. Fifty percent of the samples yields reliable intensity values with high quality factors. An original element of this study is that we made use of the PTRM-tail test of Shcherbakova et al. (2000) to help in the interpretation of the paleointensity measurements. Doing thus, only the high temperature intervals, beyond 400 degres C, were retained to obtain the most reliable estimate of the streng...

  16. 21 CFR 184.1101 - Diacetyl tartaric acid esters of mono- and diglycerides.


    ... 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 hydroxyl...

  17. 40 CFR 721.8340 - Mono esters from 2- propenoic acid (generic).


    ... 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 the...

  18. 21 CFR 172.856 - Propylene glycol mono- and diesters of fats and fatty acids.


    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Propylene glycol mono- and diesters of fats and... DIRECT ADDITION TO FOOD FOR HUMAN CONSUMPTION Multipurpose Additives § 172.856 Propylene glycol mono- and diesters of fats and fatty acids. Propylene glycol mono- and diesters of fats and fatty acids may be...

  19. 21 CFR 573.800 - Polyethylene glycol (400) mono- and dioleate.


    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Polyethylene glycol (400) mono- and dioleate. 573... DRINKING WATER OF ANIMALS Food Additive Listing § 573.800 Polyethylene glycol (400) mono- and dioleate. (a) The food additive polyethylene glycol (400) mono- and dioleate meets the following...

  20. Depth gradients in food-web processes linking habitats in large lakes: Lake Superior as an exemplar ecosystem

    Sierszen, Michael E.; Hrabik, Thomas R.; Stockwell, Jason D.; Cotter, Anne M; Hoffman, Joel C.; Yule, Daniel L.


    In large lakes around the world, depth-based changes in the abundance and distribution of invertebrate and fish species suggest that there may be concomitant changes in patterns of resource allocation. Using Lake Superior of the Laurentian Great Lakes as an example, we explored this idea through stable isotope analyses of 13 major fish taxa.

  1. The Morphometry of Lake Palmas, a Deep Natural Lake in Brazil

    Barroso, Gilberto F.; Gonçalves, Monica A.; Garcia, Fábio da C.


    Lake Palmas (A = 10.3km2) is located in the Lower Doce River Valley (LDRV), on the southeastern coast of Brazil. The Lake District of the LDRV includes 90 lakes, whose basic geomorphology is associated with the alluvial valleys of the Barreiras Formation (Cenozoic, Neogene) and with the Holocene coastal plain. This study aimed to investigate the relationship of morphometry and thermal pattern of a LDRV deep lake, Lake Palmas. A bathymetric survey carried out in 2011 and the analysis of hydrographic and wind data with a geographic information system allowed the calculation of several metrics of lake morphometry. The vertical profiling of physical and chemical variables in the water column during the wet/warm and dry/mild cold seasons of 2011 to 2013 has furnished a better understanding of the influence of the lake morphometry on its structure and function. The overdeepened basin has a subrectangular elongated shape and is aligned in a NW-SE direction in an alluvial valley with a maximum depth (Zmax) of 50.7m, a volume of 2.2×108 m3 (0.22km3) and a mean depth (Zmv) of 21.4m. These metrics suggest Lake Palmas as the deepest natural lake in Brazil. Water column profiling has indicated strong physical and chemical stratification during the wet/warm season, with a hypoxic/anoxic layer occupying one-half of the lake volume. The warm monomictic pattern of Lake Palmas, which is in an accordance to deep tropical lakes, is determined by water column mixing during the dry and mild cold season, especially under the influence of a high effective fetch associated with the incidence of cold fronts. Lake Palmas has a very long theoretical retention time, with a mean of 19.4 years. The changes observed in the hydrological flows of the tributary rivers may disturb the ecological resilience of Lake Palmas. PMID:25406062

  2. Contamination of nonylphenolic compounds in creek water, wastewater treatment plant effluents, and sediments from Lake Shihwa and vicinity, Korea: Comparison with fecal pollution

    Choi, Minkyu; Furlong, Edward T.; Moon, Hyo-Bang; Yu, Jun; Choi, Hee-Gu


    Nonylphenolic compounds (NPs), coprostanol (COP), and cholestanol, major contaminants in industrial and domestic wastewaters, were analyzed in creek water, wastewater treatment plant (WWTP) effluent, and sediment samples from artificial Lake Shihwa and its vicinity, one of the most industrialized regions in Korea. We also determined mass discharge of NPs and COP, a fecal sterol, into the lake, to understand the linkage between discharge and sediment contamination. Total NP (the sum of nonylphenol, and nonylphenol mono- and di-ethoxylates) were 0.32–875 μg L-1 in creeks, 0.61–87.0 μg L-1 in WWTP effluents, and 29.3–230 μg g-1 TOC in sediments. Concentrations of COP were 0.09–19.0 μg L-1 in creeks, 0.11–44.0 μg L-1 in WWTP effluents, and 2.51–438 μg g-1 TOC in sediments. The spatial distributions of NPs in creeks and sediments from the inshore region were different from those of COP, suggesting that Lake Shihwa contamination patterns from industrial effluents differ from those from domestic effluents. The mass discharge from the combined outfall of the WWTPs, located in the offshore region, was 2.27 kg d-1 for NPs and 1.00 kg d-1 for COP, accounting for 91% and 95% of the total discharge into Lake Shihwa, respectively. The highest concentrations of NPs and COP in sediments were found in samples at sites near the submarine outfall of the WWTPs, indicating that the submarine outfall is an important point source of wastewater pollution in Lake Shihwa.

  3. Archaea in Yellowstone Lake.

    Kan, Jinjun; Clingenpeel, Scott; Macur, Richard E; Inskeep, William P; Lovalvo, Dave; Varley, John; Gorby, Yuri; McDermott, Timothy R; Nealson, Kenneth


    The Yellowstone geothermal complex has yielded foundational discoveries that have significantly enhanced our understanding of the Archaea. This study continues on this theme, examining Yellowstone Lake and its lake floor hydrothermal vents. Significant Archaea novelty and diversity were found associated with two near-surface photic zone environments and two vents that varied in their depth, temperature and geochemical profile. Phylogenetic diversity was assessed using 454-FLX sequencing (~51,000 pyrosequencing reads; V1 and V2 regions) and Sanger sequencing of 200 near-full-length polymerase chain reaction (PCR) clones. Automated classifiers (Ribosomal Database Project (RDP) and Greengenes) were problematic for the 454-FLX reads (wrong domain or phylum), although BLAST analysis of the 454-FLX reads against the phylogenetically placed full-length Sanger sequenced PCR clones proved reliable. Most of the archaeal diversity was associated with vents, and as expected there were differences between the vents and the near-surface photic zone samples. Thaumarchaeota dominated all samples: vent-associated organisms corresponded to the largely uncharacterized Marine Group I, and in surface waters, ~69-84% of the 454-FLX reads matched archaeal clones representing organisms that are Nitrosopumilus maritimus-like (96-97% identity). Importance of the lake nitrogen cycling was also suggested by >5% of the alkaline vent phylotypes being closely related to the nitrifier Candidatus Nitrosocaldus yellowstonii. The Euryarchaeota were primarily related to the uncharacterized environmental clones that make up the Deep Sea Euryarchaeal Group or Deep Sea Hydrothermal Vent Group-6. The phylogenetic parallels of Yellowstone Lake archaea to marine microorganisms provide opportunities to examine interesting evolutionary tracks between freshwater and marine lineages.

  4. Pacific salmonines in the Great Lakes Basin

    Claramunt, Randall M.; Madenjian, Charles P.; Clapp, David; Taylor, William W.; Lynch, Abigail J.; Leonard, Nancy J.


    Pacific salmon (genus Oncorhynchus) are a valuable resource, both within their native range in the North Pacific rim and in the Great Lakes basin. Understanding their value from a biological and economic perspective in the Great Lakes, however, requires an understanding of changes in the ecosystem and of management actions that have been taken to promote system stability, integrity, and sustainable fisheries. Pacific salmonine introductions to the Great Lakes are comprised mainly of Chinook salmon, coho salmon, and steelhead and have accounted for 421, 177, and 247 million fish, respectively, stocked during 1966-2007. Stocking of Pacific salmonines has been effective in substantially reducing exotic prey fish abundances in several of the Great Lakes (e.g., lakes Michigan, Huron, and Ontario). The goal of our evaluation was to highlight differences in management strategies and perspectives across the basin, and to evaluate policies for Pacific salmonine management in the Great Lakes. Currently, a potential conflict exists between Pacific salmonine management and native fish rehabilitation goals because of the desire to sustain recreational fisheries and to develop self-sustaining populations of stocked Pacific salmonines in the Great Lakes. We provide evidence that suggests Pacific salmonines have not only become naturalized to the food webs of the Great Lakes, but that their populations (specifically Chinook salmon) may be fluctuating in concert with specific prey (i.e., alewives) whose populations are changing relative to environmental conditions and ecosystem disturbances. Remaining questions, however, are whether or not “natural” fluctuations in predator and prey provide enough “stability” in the Great Lakes food webs, and even more importantly, would a choice by managers to attempt to reduce the severity of predator-prey oscillations be antagonistic to native fish restoration efforts. We argue that, on each of the Great Lakes, managers are pursuing

  5. Seed mediated synthesis of highly mono-dispersed gold nanoparticles in the presence of hydroquinone

    Kumar, Dhiraj; Mutreja, Isha; Sykes, Peter


    Gold nanoparticles (AuNPs) are being studied for several biomedical applications, including drug delivery, biomedical imaging, contrast agents and tumor targeting. The synthesis of nanoparticles with a narrow size distribution is critical for these applications. We report the synthesis of highly mono-dispersed AuNPs by a seed mediated approach, in the presence of tri-sodium citrate and hydroquinone (HQ). AuNPs with an average size of 18 nm were used for the synthesis of highly mono-dispersed nanocrystals of an average size 40 nm, 60 nm, 80 nm and ˜100 nm; but the protocol is not limited to these sizes. The colloidal gold was subjected to UV-vis absorbance spectroscopy, showing a red shift in lambda max wavelength, peaks at 518.47 nm, 526.37 nm, 535.73 nm, 546.03 nm and 556.50 nm for AuNPs seed (18 nm), 40 nm, 60 nm, 80 nm and ˜100 nm respectively. The analysis was consistent with dynamic light scattering and electron microscopy. Hydrodynamic diameters measured were 17.6 nm, 40.8 nm, 59.8 nm, 74.1 nm, and 91.4 nm (size by dynamic light scattering—volume %); with an average poly dispersity index value of 0.088, suggesting mono-dispersity in the size distribution, which was also confirmed by transmission electron microscopy analysis. The advantage of a seed mediated approach is a multi-step growth of nanoparticle size that enables us to control the number of nanoparticles in the suspension, for size ranging from 24.5 nm to 95.8 nm. In addition, the HQ-based synthesis of colloidal nanocrystals allowed control of the particle size and size distribution by tailoring either the number of seeds, amount of gold precursor or reducing agent (HQ) in the final reaction mixture.

  6. Seed mediated synthesis of highly mono-dispersed gold nanoparticles in the presence of hydroquinone.

    Kumar, Dhiraj; Mutreja, Isha; Sykes, Peter


    Gold nanoparticles (AuNPs) are being studied for several biomedical applications, including drug delivery, biomedical imaging, contrast agents and tumor targeting. The synthesis of nanoparticles with a narrow size distribution is critical for these applications. We report the synthesis of highly mono-dispersed AuNPs by a seed mediated approach, in the presence of tri-sodium citrate and hydroquinone (HQ). AuNPs with an average size of 18 nm were used for the synthesis of highly mono-dispersed nanocrystals of an average size 40 nm, 60 nm, 80 nm and ∼100 nm; but the protocol is not limited to these sizes. The colloidal gold was subjected to UV-vis absorbance spectroscopy, showing a red shift in lambda max wavelength, peaks at 518.47 nm, 526.37 nm, 535.73 nm, 546.03 nm and 556.50 nm for AuNPs seed (18 nm), 40 nm, 60 nm, 80 nm and ∼100 nm respectively. The analysis was consistent with dynamic light scattering and electron microscopy. Hydrodynamic diameters measured were 17.6 nm, 40.8 nm, 59.8 nm, 74.1 nm, and 91.4 nm (size by dynamic light scattering-volume %); with an average poly dispersity index value of 0.088, suggesting mono-dispersity in the size distribution, which was also confirmed by transmission electron microscopy analysis. The advantage of a seed mediated approach is a multi-step growth of nanoparticle size that enables us to control the number of nanoparticles in the suspension, for size ranging from 24.5 nm to 95.8 nm. In addition, the HQ-based synthesis of colloidal nanocrystals allowed control of the particle size and size distribution by tailoring either the number of seeds, amount of gold precursor or reducing agent (HQ) in the final reaction mixture.

  7. Modification and performance evaluation of a mono-valve engine

    Behrens, Justin W.

    A four-stroke engine utilizing one tappet valve for both the intake and exhaust gas exchange processes has been built and evaluated. The engine operates under its own power, but has a reduced power capacity than the conventional 2-valve engine. The reduction in power is traced to higher than expected amounts of exhaust gases flowing back into the intake system. Design changes to the cylinder head will fix the back flow problems, but the future capacity of mono-valve engine technology cannot be estimated. The back flow of exhaust gases increases the exhaust gas recirculation (EGR) rate and deteriorates combustion. Intake pressure data shows the mono-valve engine requires an advanced intake valve closing (IVC) time to prevent back flow of charge air. A single actuation camshaft with advanced IVC was tested in the mono-valve engine, and was found to improve exhaust scavenging at TDC and nearly eliminated all charge air back flow at IVC. The optimum IVC timing is shown to be approximately 30 crank angle degrees after BDC. The mono-valve cylinder head utilizes a rotary valve positioned above the tappet valve. The open spaces inside the rotary valveand between the rotary valve and tappet valve represent a common volume that needs to be reduced in order to reduce the base EGR rate. Multiple rotary valve configurations were tested, and the size of the common volume was found to have no effect on back flow but a direct effect on the EGR rate and engine performance. The position of the rotary valve with respect to crank angle has a direct effect on the scavenging process. Optimum scavenging occurs when the intake port is opened just after TDC.

  8. Mono(2-ethylhexyl)phthalate and mono-n-butyl phthalate activation of peroxisome proliferator activated-receptors alpha and gamma in breast.

    Venkata, Nagaraj Gopisetty; Robinson, Jodie A; Cabot, Peter J; Davis, Barbara; Monteith, Greg R; Roberts-Thomson, Sarah J


    The phthalates di(2-ethylhexyl)phthalate (DEHP) and di-n-butyl phthalate (DBP) are environmental contaminants with significant human exposures. Both compounds are known reproductive toxins in rodents and DEHP also induces rodent hepatocarcinogenesis in a process believed to be mediated via the peroxisome proliferator-activated receptor alpha (PPARalpha). DEHP and DBP are metabolised to their respective monoesters, mono-(2-ethylhexyl)phthalate (MEHP) and mono-n-butyl phthalate (MBP), which are the active metabolites. MEHP also activates another member of the PPAR subfamily, PPARgamma. The effects of PPARalpha and PPARgamma activation in human breast cells appears to be opposing; PPARalpha activators in breast cells cause an increase in proliferation, while PPARgamma activation in breast cells is associated with differentiation and an inhibition of cell proliferation. Further to this the activation of the PPARs is cell and ligand specific, suggesting the importance of examining the effect of MEHP and MBP on the activation of PPARalpha, PPARbeta and PPARgamma in human breast. We used the common model of human breast cancer MCF-7 and examined the ability of MEHP and MBP to activate human PPARs in this system. The ability of MBP and MEHP to block PPAR responses was also assessed. We found that both human PPARalpha and PPARgamma were activated by MEHP whereas MEHP could not activate PPARbeta. MBP was unable to activate any PPAR isoforms in this breast model, despite being a weak peroxisome proliferator in liver, although MBP was an antagonist for both PPARgamma and PPARbeta. Our results suggest that the toxicological consequences of MEHP in the breast could be complex given the opposing effects of PPARalpha and PPARgamma in human breast cells.

  9. Using Satellite Imagery to Monitor the Major Lakes; Case Study Lake Hamun

    Norouzi, H.; Islam, R.; Bah, A.; AghaKouchak, A.


    Proper lakes function can ease the impact of floods and drought especially in arid and semi-arid regions. They are important environmentally and can directly affect human lives. Better understanding of the effect of climate change and human-driven changes on lakes would provide invaluable information for policy-makers and local people. As part of a comprehensive study, we aim to monitor the land-cover/ land-use changes in the world's major lakes using satellite observations. As a case study, Hamun Lake which is a pluvial Lake, also known as shallow Lake, located on the south-east of Iran and adjacent to Afghanistan, and Pakistan borders is investigated. The Lake is the main source of resources (agriculture, fishing and hunting) for the people around it and politically important in the region since it is shared among three different countries. The purpose of the research is to find the Lake's area from 1972 to 2015 and to see if any drought or water resources management has affected the lake. Analyzing satellites imagery from Landsat shows that the area of the Lake changes seasonally and intra-annually. Significant seasonal effects are found in 1975,1977, 1987, 1993, 1996, 1998, 2000, 2009 and 2011, as well as, substantial amount of shallow water is found throughout the years. The precipitation records as well as drought historical records are studied for the lake's basin. Meteorological studies suggest that the drought, decrease of rainfalls in the province and the improper management of the Lake have caused environmental, economic and geographical consequences. The results reveal that lake has experienced at least two prolong dryings since 1972 which drought cannot solely be blamed as main forcing factor.Proper lakes function can ease the impact of floods and drought especially in arid and semi-arid regions. They are important environmentally and can directly affect human lives. Better understanding of the effect of climate change and human-driven changes on lakes

  10. Gamma spectra pictures using a digital plotter. Program MONO; Representacion de Espectros directos mediante un trazado digital. Prograa MONO

    Los Arcos, J. M.


    The program MONO has been written for a CALCOMP-936 digital plotter operating off- -line with a UMI VAC 1106 computer, to obtain graphic representations of single gamma spectra stored on magnetic tape. It allows to plot the whole spectrum or only a part, as well as to draw a given spectrum on the same or different picture than the previous one. Ten representation scales are available and at up nine comment lines can be written in a graphic. (Author) 4 refs.

  11. Climate-driven changes in grassland vegetation, snow cover, and lake water of the Qinghai Lake basin

    Wang, Xuelu; Liang, Tiangang; Xie, Hongjie; Huang, Xiaodong; Lin, Huilong


    Qinghai Lake basin and the lake have undergone significant changes in recent decades. We examine MODIS-derived grassland vegetation and snow cover of the Qinghai Lake basin and their relations with climate parameters during 2001 to 2010. Results show: (1) temperature and precipitation of the Qinghai Lake basin increased while evaporation decreased; (2) most of the grassland areas improved due to increased temperature and growing season precipitation; (3) weak relations between snow cover and precipitation/vegetation; (4) a significantly negative correlation between lake area and temperature (r=-0.9, presponsible for the degradation of vegetation cover in Namco Lake basin. These results suggest different responses to the similar warming climate: improved (degraded) ecological condition and productive capacity of the Qinghai Lake basin (Namco Lake basin).

  12. Bathymetry of Lake Erie and Lake Saint Clair

    National Oceanic and Atmospheric Administration, Department of Commerce — Bathymetry of Lake Erie and Lake Saint Clair has been compiled as a component of a NOAA project to rescue Great Lakes lake floor geological and geophysical data and...

  13. Subglacial Lake McGregor, south-central Alberta, Canada

    Munro-Stasiuk, Mandy J.


    It is proposed that a lake, here named "Subglacial Lake McGregor", existed beneath the Laurentide Ice Sheet at, or near, the last glacial maximum. The lake resided in the ancient buried McGregor and Tee Pee preglacial valleys, which are now mostly filled with glacigenic deposits. The greatest thickness of sediment in the valleys is in the form of chaotically deposited lake beds that were laid down in a subaqueous environment by a number of process: gravity flow, water transport, and suspension settling. Topographic, sedimentary, and stratigraphic evidence point to a subglacial, not a proglacial, origin for the beds. During the early stages of lake existence, ice movement was significant as there are numerous sets of shear planes in the sedimentary beds. This indicates that the lake filled (lake sedimentation) and drained (shearing of the beds by overlying ice when ice contacted the bed) often. Thus, early in its history, the lake(s) was/were ephemeral. During the later stages of lake existence, the lake was relatively stable with no rapid draining or influx of sediment. Gradual drainage of the lake resulted in lowering of the ice onto the lake beds resulting in subglacial till deposition. Drainage was not a single continuous event. Rather it was characterized by multiple phases of near total drainage (till deposition), followed by water accumulation (lake sedimentation). Water accumulation events became successively less significant reflected by thinning of lake beds and thickening of till beds higher in the stratigraphic sequence. Since subglacial lake sedimentation appears to be restricted to the subglacial valleys, it is suggested that the valleys acted as a large-scale interconnected cavity system that both stored and transported water. It is also suggested that these acted as the main routes of water flow beneath the Laurentide Ice Sheet.

  14. The relationship between mono-abundance and mono-age stellar populations in the Milky Way disk

    Minchev, I; Chiappini, C; Martig, M; Anders, F; Matijevic, G; de Jong, R S


    Studying the Milky Way disk structure using stars in narrow bins of [Fe/H] and [alpha/Fe] has recently been proposed as a powerful method to understand the Galactic thick and thin disk formation. It has been assumed so far that these mono-abundance populations (MAPs) are also coeval, or mono-age, populations. Here we study this relationship for a Milky Way chemo-dynamical model and show that equivalence between MAPs and mono-age populations exists only for the high-[alpha/Fe] tail, where the chemical evolution curves of different Galactic radii are far apart. At lower [alpha/Fe]-values a MAP is composed of stars with a range in ages, even for small observational uncertainties and a small MAP bin size. Due to the disk inside-out formation, for these MAPs younger stars are typically located at larger radii, which results in negative radial age gradients that can be as large as 2 Gyr/kpc. Positive radial age gradients can result for MAPs at the lowest [alpha/Fe] and highest [Fe/H] end. Such variations with age p...

  15. Outflows of groundwater in lakes: case study of Lake Raduńske Górne

    Cieśliński Roman


    Full Text Available The aim of the study was to locate and describe groundwater outflows in a selected lake basin. The study hypothesis was based on the fact that, according to the specialist literature, one of the forms of lake water supply is through groundwater outflows. It was also assumed that the lakes of the Kashubian Lake District are characterised by such a form of lake water supply. The time scope of the work included the period from January 2011 to September 2012. The spatial scope of the work included the area of Lake Raduńskie Górne, located in the Kashubian Lake District in north Poland. The research plot was in the north-eastern part of the lake. Office works were aimed at gathering and studying source materials and maps. Cartographic materials were analysed with the use of the MapInfo Professional 9.5. The purpose of the field work was to find the groundwater outflows in the basin of Lake Raduńskie Górne. During the field research diving was carried out in the lake. During the dive audiovisual documentation was conducted using a Nikon D90 camera with Ikelite underwater housing for Nikon D90 and an Ikelite DS 161 movie substrobe, as well as a GoPro HD HERO 2 Outdoor camera. During the project, four groundwater outflows were found. In order to examine these springs audiovisual and photographic documentation was made. To systematise the typology of the discovered springs, new nomenclature was suggested, namely under-lake springs with subtypes: an under-lake slope spring and under-lake offshore spring

  16. Heterogeneous glacial lake changes and links of lake expansions to the rapid thinning of adjacent glacier termini in the Himalayas

    Song, Chunqiao; Sheng, Yongwei; Wang, Jida; Ke, Linghong; Madson, Austin; Nie, Yong


    Glacier mass loss in the Himalayas has far-reaching implications for the alteration of regional hydrologic regimes, an increased risk of glacial lake outburst, downstream water resource abundance, and contributions to sea level rise. However, the mass losses of Himalayan glaciers are not well understood towing to the scarcity of observations and the heterogeneous responses of Himalayan glaciers to climate change and local factors (e.g., glacier surge, interacting with proglacial lakes). In particular, there is a lack of understanding on the unique interactions between moraine-dammed glacial lakes and their effects on debris cover on valley glacier termini. In this study, we examined the temporal evolution of 151 large glacial lakes across the Himalayas and then classified these glacial lakes into three categories: proglacial lakes in contact with full or partial debris-covered glaciers (debris-contact lakes), ice cliff-contact lakes, and non-glacier-contact lakes. The results show that debris-contact lakes experienced a dramatic areal increase of 36.5% over the years 2000 to 2014, while the latter two categories of lakes remained generally stable. The majority of lake expansions occurred at the glacier front without marked lake level rises. This suggests that the rapid expansion of these debris-contact lakes can be largely attributed to the thinning of debris-covered ice as caused by the melting of glacial fronts and the subsequent glacial retreat. We reconstructed the height variations of glacier fronts in contact with 57 different proglacial lakes during the years 2000 to 2014. These reconstructed surface elevation changes of debris-covered, lake-contact glacier fronts reveal significant thinning trends with considerable lowering rates that range from 1.0 to 9.7 m/y. Our study reveals that a substantial average ice thinning of 3.9 m/y occurred at the glacier fronts that are in contact with glacial lakes.

  17. Recent warming of lake Kivu.

    Sergei Katsev

    Full Text Available Lake Kivu in East Africa has gained notoriety for its prodigious amounts of dissolved methane and dangers of limnic eruption. Being meromictic, it is also expected to accumulate heat due to rising regional air temperatures. To investigate the warming trend and distinguish between atmospheric and geothermal heating sources, we compiled historical temperature data, performed measurements with logging instruments, and simulated heat propagation. We also performed isotopic analyses of water from the lake's main basin and isolated Kabuno Bay. The results reveal that the lake surface is warming at the rate of 0.12°C per decade, which matches the warming rates in other East African lakes. Temperatures increase throughout the entire water column. Though warming is strongest near the surface, warming rates in the deep waters cannot be accounted for solely by propagation of atmospheric heat at presently assumed rates of vertical mixing. Unless the transport rates are significantly higher than presently believed, this indicates significant contributions from subterranean heat sources. Temperature time series in the deep monimolimnion suggest evidence of convection. The progressive deepening of the depth of temperature minimum in the water column is expected to accelerate the warming in deeper waters. The warming trend, however, is unlikely to strongly affect the physical stability of the lake, which depends primarily on salinity gradient.


    James K. Campbell


    Full Text Available Investigation into trust has become a topical issue in current socialscience research. This is, in large part, a result of a perception that trust in institutions has declined markedly in the past two decades. This paper investigates trust in some of Penang’s civil associations as a way of measuring the health of social capital in Penang. It focuses on issues of trust and diversity since both are critical issues in Malaysian society in general and civil associations in particular. We began our analysis expecting higher forms of trust among members in the mono-ethnic associations, based on the power of bonding. However, findings from this study tend to suggest that rather than leading to lesser trust and infectiveness, involvement in mixed-ethnic associations have in fact generated higher trust among their members. These findings reveal an interesting corrective to more pessimistic view on the relationshipbetween trust and diversity. Data from this study also provide important insight into how bridging between different people in associations marked by diversity can accentuate trust over and above the levels found in associations were bonding between like types is the dominant characteristic. The data also indicate that for both, mono-ethnic and mixed-ethnic associations, it is the extent of members’ involvements in their associations that form trust and not vice versa.

  19. Dissecting simulated disk galaxies I: the structure of mono-age populations

    Martig, Marie; Flynn, Chris


    We study seven simulated disk galaxies, three with a quiescent merger history, and four with mergers in their last 9 Gyr of evolution. We compare their structure at z=0 by decomposing them into "mono-age populations" (MAPs) of stars within 500 Myr age bins. All studied galaxies undergo a phase of merging activity at high redshift, so that stars older than 9 Gyr are found in a centrally concentrated component, while younger stars are mostly found in disks. We find that most MAPs have simple exponential radial and vertical density profiles, with a scale-height that typically increases with age. Because a large range of merger histories can create populations with simple structures, this suggests that the simplicity of the structure of mono-abundance populations observed in the Milky Way by Bovy et al. (2012b,c) is not necessarily a direct indicator of a quiescent history for the Milky Way. Similarly, the anti-correlation between scale-length and scale-height does not necessarily imply a merger-free history. How...

  20. Europa's Great Lakes

    Schmidt, B. E.; Blankenship, D. D.; Patterson, G. W.; Schenk, P. M.


    Unique to the surface of Europa, chaos terrain is diagnostic of the properties and dynamics of its icy shell. While models have suggested that partial melt within a thick shell or melt-through of a thin shell may form chaos, neither model has been able to definitively explain all observations of chaos terrain. However, we present a new model that suggests large melt lenses form within the shell and that water-ice interactions above and within these lenses drive the production of chaos. Our analysis of the geomorphology of Conamara Chaos and Thera Macula, was used to infer and test a four-stage lens-collapse chaos formation model: 1) Thermal plumes of warm, pure ice ascend through the shell melting the impure brittle ice above, producing a lake of briny water and surface down draw due to volume reduction. 2) Surface deflection and driving force from the plume below hydraulically seals the water in place. 3) Extension of the brittle ice lid generates fractures from below, allowing brines to enter and fluidize the ice matrix. 4) As the lens and now brash matrix refreeze, thermal expansion creates domes and raises the chaos feature above the background terrain. This new "lense-collapse" model indicates that chaos features form in the presence of a great deal of liquid water, and that large liquid water bodies exist within 3km of Europa's surface comparable in volume to the North American Great Lakes. The detection of shallow subsurface "lakes" implies that the ice shell is recycling rapidly and that Europa may be currently active. In this presentation, we will explore environments on Europa and their analogs on Earth, from collapsing Antarctic ice shelves to to subglacial volcanos in Iceland. I will present these new analyses, and describe how this new perspective informs the debate about Europa's habitability and future exploration.

  1. Lake metabolism scales with lake morphometry and catchment conditions

    Stæhr, Peter A.; Baastrup-Spohr, Lars; Jensen, Kaj Sand


    We used a comparative data set for 25 lakes in Denmark sampled during summer to explore the influence of lake morphometry, catchment conditions, light availability and nutrient input on lake metabolism. We found that (1) gross primary production (GPP) and community respiration (R) decline with lake...... in lake morphometry and catchment conditions when comparing metabolic responses of lakes to human impacts....

  2. A population on the rise: The origin of deepwater sculpin in Lake Ontario

    Welsh, Amy B.; Scribner, Kim T.; Stott, Wendylee; Walsh, Maureen


    Deepwater sculpin, Myoxocephalus thompsonii, were thought to have been extirpated from Lake Ontario. However, in recent years, abundance has increased and recruitment has been documented. There are two hypotheses concerning the origin of the current Lake Ontario deepwater sculpin population. First, individuals from the upper Great Lakes may have recolonized Lake Ontario. Alternatively, the Lake Ontario population may have not been extirpated, and the remnant population has recovered naturally. To test these hypotheses, eight microsatellite loci were used to analyze samples from the current Lake Ontario population, museum specimens from the historic Lake Ontario population, and current upper Great Lakes populations. The genetic data suggest that historically throughout the Great Lakes, deepwater sculpin exhibited low levels of spatial genetic structure. Approximate Bayesian Computation analyses support the hypothesis that the current Lake Ontario population is more closely related to populations in the upper Great Lakes than to the historic Lake Ontario samples, indicating that the current Lake Ontario population likely resulted from recolonization from the Upper Great Lakes. The current Lake Ontario population has reduced allelic diversity relative to upper Great Lakes populations, indicating a possible founder effect. This study demonstrates the role life history variation can play in recolonization success. The pelagic larval phase of the deepwater sculpin allowed recolonization of Lake Ontario via passive larval drift.

  3. Arsenic, Prokaryotes, and Closed Basin Soda Lakes of the Western USA.

    Oremland, R. S.


    A number of saline, alkaline soda lakes in the Great Basin and Mojave Desert of the United States have unusually high concentrations of inorganic arsenic dissolved in their brine-waters. The arsenic originates from natural rather than anthropogenic sources, namely volcanic hydrothermal inputs. When this influx is coupled with evapo-concentration and the unique chemical behavior of arsenic oxyanions in alkaline waters, it results in extremely elevated As concentrations. For example, the salinity and arsenate levels of 3 comparable soda lakes (pH 9.8) are: Big Soda Lake, NV (27 g/L; 20 uM), Mono Lake, CA (90 g/L; 200 uM), and Searles Lake, CA (340 g/L; 3,900 uM). The arsenic oxidation state changes from As5+ (arsenate) to As3+ (arsenite) with vertical transition from their oxygenated surface water to their anoxic bottom water. Similar phenomena occur in their littoral sediments. These lakes also harbor active populations of prokaryotes that achieve these As redox changes either by using arsenate as an electron acceptor for respiration, or by employing arsenite as a chemoautotrophic electron donor. Diverse microorganisms have been identified in these systems that are involved in the biogeochemical cycling of arsenic therein, and in situ studies made with radiotracer (73As) and other means showed that these redox reactions occur at rapid rates. However, other than their use for waterfowl hunting (Big Soda Lake), as a region of scenic beauty (Mono Lake), or as a resource for the chemical industry (Searles Lake), there is little concern about the arsenic in these systems because the waters are not potable and their chemistry is too extreme to allow for the presence of fish. Nonetheless, microbial processes that govern arsenic biogeochemistry can greatly influence the hydrologic mobility and toxicity of this element in freshwater systems, such as drinking water aquifers. Moreover, anthropogenic inputs of arsenic can also occur in closed basin lakes in this region, such as

  4. iOS Development using MonoTouch Cookbook

    Tavlikos, Dimitris


    The book is written in a cookbook style, presenting examples in the style of recipes, allowing you to go directly to your topic of interest, or follow topics throughout a chapter to gain in-depth knowledge. This book is essential for C# and .NET developers with no previous experience in iOS development and Objective-C developers that want to make a transition to the benefits of MonoTouch and the C# language, for creating complete, compelling iPhone, iPod and iPad applications and deploying them to the App Store.

  5. IRIS Toxicological Review of Ethylene Glycol Mono-Butyl ...

    EPA released the draft report, Toxicological Review for Ethylene Glycol Mono-Butyl Ether , that was distributed to Federal agencies and White House Offices for comment during the Science Discussion step of the IRIS Assessment Development Process. Comments received from other Federal agencies and White House Offices are provided below with external peer review panel comments. EPA is conducting a peer review of the scientific basis supporting the human health hazard and dose-response assessment of EGBE that will appear on the Integrated Risk Information System (IRIS) database.

  6. DNR 24K Lakes

    Minnesota Department of Natural Resources — Medium scale lake polygons derived from the National Wetlands Inventory (NWI) polygons and MnDOT Basemap lake delineations. Integrated with the DNR 24K Streams...

  7. Absence of germline mono-allelic promoter hypermethylation of the CDH1 gene in gastric cancer patients

    Ozawa Takachika


    Full Text Available Abstract Background Germline mono-allelic promoter hypermethylation of the MLH1 or MSH2 gene in families with hereditary nonpolyposis colorectal cancer has recently been reported. The purpose of this study was to evaluate if germline promoter hypermethylation of the tumor suppressor gene CDH1 (E-cadherin might cause predisposition to gastric cancer. Methods We prepared two groups of samples, a group of blood samples from 22 patients with familial gastric cancer or early-onset gastric cancer selected from among 39 patients, and a group of non-cancerous gastric tissue samples from 18 patients with sporadic gastric cancer showing loss of CDH1 expression selected from among 159 patients. We then investigated the allele-specific methylation status of the CDH1 promoter by bisulfite sequencing of multiple clones. Results Although there was a difference between the methylation level of the two alleles in some samples, there was no mono-allelic promoter hypermethylation in any of the samples. Conclusion These results suggest that germline mono-allelic hypermethylation of the CDH1 promoter is not a major predisposing factor for gastric cancer.

  8. N-terminal mono-PEGylation of growth hormone antagonist: correlation of PEG size and pharmacodynamic behavior.

    Wu, Ling; Ho, Sa V; Wang, Wei; Gao, Jianping; Zhang, Guifeng; Su, Zhiguo; Hu, Tao


    Growth hormone antagonist (GHA), an analog of growth hormone (GH), can inhibit GH action and treat acromegaly. However, GHA suffers from a short plasma half-life of 15-20 min that has limited its clinical application. PEGylation, conjugation with polyethylene glycol (PEG), can increase the plasma half-life of GHA. Single PEG attachment (mono-PEGylation) at N-terminus of GHA has the advantages of product homogeneity and minimization of the bioactivity loss. Conjugation of large PEG molecule may increase the plasma half-life but could potentially decrease the bioactivity of GHA, due to the steric shielding effect of PEG. Thus, N-terminal mono-PEGylation of GHA with 20 kDa and 40 kDa PEG were used to look for a balance of the two competing factors. Sedimentation velocity analysis suggested that 40 kDa PEG was more efficient than 20 kDa PEG to elongate the molecular shape of the conjugate. As reflected by marginal suppression of insulin-like growth factor I (IGF-I), GHA conjugated with 40 kDa PEG was statistically indistinguishable from the saline solution that could not inhibit GH action. In contrast, GHA conjugated with 20kDa PEG can apparently inhibit GH action, as reflected by IGF-I suppression of 30-43%. Thus, our work demonstrated the effective therapeutic potency of N-terminally mono-PEGylated GHA.

  9. Crystal growth of 50 cm square mono-like Si by directional solidification and its characterization

    Miyamura, Y.; Harada, H.; Jiptner, K.; Chen, J.; Prakash, R. R.; Nakano, S.; Gao, B.; Kakimoto, K.; Sekiguchi, T.


    Seed-assisted growth of mono crystalline-like Silicon (mono-like Si) ingots of 50 cm square has been performed. By controlling the shape of the liquid-solid interface, a mono-like crystal was grown from a small seed of 20 cm diameter. Several developments to reduce the carbon incorporation have been realized as can be seen from the shiny ingot surfaces. The dislocation density is reduced to the order of 104 cm-2.


    selected satellite lakes and Mara River in Lake Victoria basin, during wet and dry seasons in. 2002. Samples ... The wet season recorded higher biomass in all satellite lakes than during the dry season (t = 2.476, DF ..... communication. Urbana ...

  11. Two novel human members of an emerging mammalian gene family related to mono-ADP-ribosylating bacterial toxins

    Koch-Nolte, F.; Haag, F.; Braren, R. [Univ. Hospital, Hamburg (Germany)] [and others


    Mono-ADP-ribosylation is one of the posttranslational protein modifications regulating cellular metabolism, e.g., nitrogen fixation, in prokaryotes. Several bacterial toxins mono-ADP-ribosylate and inactivate specific proteins in their animal hosts. Recently, two mammalian GPI-anchored cell surface enzymes with similar activities were cloned (designated ART1 and ART2). We have now identified six related expressed sequence tags (ESTs) in the public database and cloned the two novel human genes from which these are derived (designated ART3 and ART4). The deduced amino acid sequences of the predicted gene products show 28% sequence identity to one another and 32-41% identity vs the muscle and T cell enzymes. They contain signal peptide sequences characteristic of GPI anchorage. Southern Zoo blot analyses suggest the presence of related genes in other mammalian species. By PCR screening of somatic cell hybrids and by in situ hybridization, we have mapped the two genes to human chromosomes 4p14-p15.l and 12q13.2- q13.3. Northern blot analyses show that these genes are specifically expressed in testis and spleen, respectively. Comparison of genomic and cDNA sequences reveals a conserved exon/intron structure, with an unusually large exon encoding the predicted mature membrane proteins. Secondary structure prediction analyses indicate conserved motifs and amino acid residues consistent with a common ancestry of this emerging mammalian enzyme family and bacterial mono(ADP-ribosyl)transferases. It is possible that the four human gene family members identified so far represent the {open_quotes}tip of an iceberg,{close_quote} i.e., a larger family of enzymes that influences the function of target proteins via mono-ADP-ribosylation. 35 refs., 4 figs.

  12. A Synoptic Climatology of Heavy Rain Events in the Lake Eyre and Lake Frome Catchments

    Michael John Pook


    Full Text Available The rare occasions when Lake Eyre in central, southern Australia fills with water excite great interest and produce major ecological responses. The filling of other smaller lakes such as Lake Frome, have less impact but can contribute important information about the current and past climates of these arid regions. Here, the dominant synoptic systems responsible for heavy rainfall over the catchments of Lake Eyre and Lake Frome since 1950 are identified and compared. Heavy rain events are defined as those where the mean catchment rainfall for 24 hours reaches a prescribed threshold. There were 25 such daily events at Lake Eyre and 28 in the Lake Frome catchment. The combination of a monsoon trough at mean sea level and a geopotential trough in the mid-troposphere was found to be the synoptic system responsible for the majority of the heavy rain events affecting Lake Eyre and one in five of the events at Lake Frome. Complex fronts where subtropical interactions occurred with Southern Ocean fronts also contributed over 20% of the heavy rainfall events in the Frome catchment. Surface troughs without upper air support were found to be associated with 10% or fewer of events in each catchment, indicating that mean sea level pressure analyses alone do not adequately capture the complexity of the heavy rainfall events. At least 80% of the heavy rain events across both catchments occurred when the Southern Oscillation Index (SOI was in its positive phase, and for Lake Frome, the SOI exceeded +10 on 60% of occasions, suggesting that the background atmospheric state in the Pacific Ocean was tilted towards La Niña. Hydrological modeling of the catchments suggests that the 12-month running mean of the soil moisture in a sub-surface layer provides a low frequency filter of the precipitation and matches measured lake levels relatively well.

  13. Mono-Energy Coronary Angiography with a Compact Synchrotron Source

    Eggl, Elena; Mechlem, Korbinian; Braig, Eva; Kulpe, Stephanie; Dierolf, Martin; Günther, Benedikt; Achterhold, Klaus; Herzen, Julia; Gleich, Bernhard; Rummeny, Ernst; Noёl, Peter B.; Pfeiffer, Franz; Muenzel, Daniela


    X-ray coronary angiography is an invaluable tool for the diagnosis of coronary artery disease. However, the use of iodine-based contrast media can be contraindicated for patients who present with chronic renal insufficiency or with severe iodine allergy. These patients could benefit from a reduced contrast agent concentration, possibly achieved through application of a mono-energetic x-ray beam. While large-scale synchrotrons are impractical for daily clinical use, the technology of compact synchrotron sources strongly advanced during the last decade. Here we present a quantitative analysis of the benefits a compact synchrotron source can offer in coronary angiography. Simulated projection data from quasi-mono-energetic and conventional x-ray tube spectra is used for a CNR comparison. Results show that compact synchrotron spectra would allow for a significant reduction of contrast media. Experimentally, we demonstrate the feasibility of coronary angiography at the Munich Compact Light Source, the first commercial installation of a compact synchrotron source.

  14. Mono(ADP-ribosylation) in rat liver mitochondria.

    Frei, B; Richter, C


    This paper investigates protein mono(ADP-ribosylation) in rat liver mitochondria. In isolated inner mitochondrial membranes, in the presence of both ADP-ribose and NAD+, a protein is mono-(ADP-ribosylated) with high specificity. The reaction apparently consists of enzymatic NAD+ glycohydrolysis and subsequent binding of free ADP-ribose to the acceptor protein. In terms of chemical stability, the resulting bond is unique among the ADP-ribose linkages thus far characterized. Formation of a Schiff base adduct between free ADP-ribose and the acceptor protein is excluded. In intact mitochondria at least three classes of proteins are ADP-ribosylated in vivo. One ADP-ribose-protein linkage is of the carboxylate ester type as indicated by its lability in neutral buffer. Another class of ADP-ribosylated proteins requires hydroxylamine for release of ADP-ribose. The third class is stable in hydroxylamine but labile to alkali, similar to the ADP-ribose-cysteine linkage in transducin formed by pertussis toxin.

  15. Leptonic mono-top from single stop production at LHC

    Duan, Guang Hua; Wu, Lei; Yang, Jin Min; Zhang, Mengchao


    Top squark (stop) can be produced via QCD interaction but also the electroweak interaction at the LHC. In this paper, we investigate the observability of the associated production of stop and chargino, $pp \\to \\tilde{t}_1\\tilde{\\chi}^-_1$, in compressed electroweakino scenario at the 14 TeV LHC. Due to the small mass-splitting between the lightest neutralino ($\\tilde{\\chi}^0_1$) and chargino ($\\tilde{\\chi}^-_1$), such a single stop production can give a mono-top signature through the stop decay $\\tilde{t}_1 \\to t \\tilde{\\chi}^0_1$. Focusing on the leptonic mono-top channel, we propose a lab-frame observable $\\cos\\theta_{b\\ell}$ to reduce the SM backgrounds in virtue of a boosted top quark from the stop decay. We find that the single stop production can be probed at $2\\sigma$ level at the HL-LHC for $m_{\\tilde{t}_1}<760$ GeV and $m_{\\tilde{\\chi}^0_1}<150$ GeV.

  16. Mono-W Dark Matter Signals at the LHC: Simplified Model Analysis

    Bell, Nicole F; Leane, Rebecca K


    We study mono-W signals of dark matter (DM) production at the LHC, in the context of gauge invariant renormalizable models. We analyze two simplified models, one involving an s-channel Z' mediator and the other a t-channel colored scalar mediator, and consider examples in which the DM-quark couplings are either isospin conserving or isospin violating after electroweak symmetry breaking. While previous work on mono-W signals have focused on isospin violating EFTs, obtaining very strong limits, we find that isospin violating effects are small once such physics is embedded into a gauge invariant simplified model. We thus find that the 8 TeV mono-W results are much less constraining than those arising from mono-jet searches. Considering both the leptonic (mono-lepton) and hadronic (mono fat jet) decays of the W, we determine the 14 TeV LHC reach of the mono-W searches with 3000 fb$^{-1}$ of data. While a mono-W signal would provide an important complement to a mono-jet discovery channel, existing constraints on t...

  17. Charcoal deposition and redeposition in Elk Lake, Minnesota, USA

    Platt, Bradbury J.


    Sedimentary charcoal, diatom and phytolith records of the past 1500 years at Elk Lake, Minnesota, in combination with sediment trap studies and a transect of surface sediment samples, document the mechanisms by which previously deposited charcoal is redeposited and finally buried in this lake. The frequent correspondence of high diatom concentrations and peaks of phytolith and charcoal fragments suggest that currents and turbulence related to lake circulation are responsible for winnowing charcoal and phytoliths from shallow water depositional sites to deeper areas of the lake. High diatom concentrations in the record relate to increased nutrient fluxes also supplied by circulation. Despite the fact that the watershed and area around Elk Lake has not been burned since AD 1922, charcoal continues to reach the profundal zone from littoral source areas in Elk Lake. The variable redeposition of within-lake charcoal requires evaluation before fire-history records can be related to global, regional or even local fire events.

  18. Microbial diversity in lake sediments detected by PCR-DGGE

    Xinqing ZHAO; Liuyan YANG; Can CHEN; Lin XIAO; Lijuan JIANG; Zhe MA; Haowei ZHU; Zhenyang YU; Daqiang YIN


    In this study,PCR-denaturing gradient gel electrophoresis (DGGE) was applied to analyze the microbial communities in lake sediments from Lake Xuanwu,Lake Mochou in Nanjing and Lake Taihu in Wuxi.Sediment samples from seven locations in three lakes were collected and their genomic DNAs were extracted.The DNA yields of the sediments of Lake Xuanwu and Lake Mochou were high (10 μg/g),while that of sediments in Lake Taihu was relatively low.After DNA purification,the 16S rDNA genes (V3 to V5 region) were amplified and the amplified DNA fragments were separated by parallel DGGE.The DGGE profiles showed that there were five common bands in all the lake sediment samples indicating that there were similarities among the populations of microorganisms in all the lake sediments.The DGGE profiles of Lake Xuanwu and Lake Mochou were similar and about 20 types of micro-organisms were identified in the sediment samples of both lakes.These results suggest that the sediment samples of these two city lakes (Xuanwu,Mochou) have similar microbial communities.However,the DGGE profiles of sediment samples in Lake Taihu were significantly differ-ent from these two lakes.Furthermore,the DGGE pro-files of sediment samples in different locations in Lake Taihu were also different,suggesting that the microbial communities in Lake Taihu are more diversified than those in Lake Xuanwu and Lake Mochou.The differences in microbial diversity may be caused by the different environmental conditions,such as redox potential,pH,and the concentrations of organic matters.Seven major bands of 16S rDNA genes fragments from the DGGE profiles of sediment samples were further re-amplified and sequenced.The results of sequencing analysis indicate that five sequences shared 99%-100% homology with known sequences (Bacillus and Brevibacillus,uncultured bacteria),while the other two sequences shared 93%-96% homology with known sequences (Acinetobacter,and Bacillus).The study shows that the PCR-DGGE tech

  19. Multiple isomers in the photoelectron spectra of small mono-niobium carbide clusters

    Iordanov, Ivan; Sofo, Jorge O.


    We calculate the photoelectron spectrum of small mono-niobium carbide clusters (NbCn) using density functional theory for clusters with n = 2-7 and the symmetry adapted cluster configuration interaction method for the smallest clusters (n = 2-4). Theoretical spectra of a single structure cannot explain all peaks present in the spectrum measured by Zhai et al. [J. Chem. Phys. 115, 5170 (2001)]. However, we can match all peaks in the experimental spectra if we assume that the beam contains a combination of cyclic and linear structures. This finding is even more surprising given the fact that some of the excited metastable geometries have energies as large as 0.5 eV above the ground state. Our result is confirmed by both theoretical approaches. We suggest further experiments, using additional beam cooling, to corroborate this observation.

  20. Modeling toxaphene behavior in the Great Lakes.

    Xia, Xiaoyan; Hopke, Philip K; Holsen, Thomas M; Crimmins, Bernard S


    Chlorinated camphenes, toxaphene, are persistent organic pollutants of concern in the Great Lakes since elevated concentrations are found in various media throughout the system. While concentrations have decreased since their peak values in the 1970s and 80s, recent measurements have shown that the rate of this decline in Lake Superior has decreased significantly. This modeling study focused on toxaphene cycling in the Great Lakes and was performed primarily to determine if elevated water and fish concentrations in Lake Superior can be explained by physical differences among the lakes. Specifically, the coastal zone model for persistent organic pollutants (CoZMo-POP), a fugacity-based multimedia fate model, was used to calculate toxaphene concentrations in the atmosphere, water, soil, sediment, and biota. The performance of the model was evaluated by comparing calculated and reported concentrations in these compartments. In general, simulated and observed concentrations agree within one order of magnitude. Both model results and observed values indicate that toxaphene concentrations have declined in water and biota since the 1980s primarily as the result of decreased atmospheric deposition rates. Overall the model results suggest that the CoZMo-POP2 model does a reasonable job in simulating toxaphene variations in the Great Lakes basin. The results suggest that the recent findings of higher toxaphene concentrations in Lake Superior can be explained by differences in the physical properties of the lake (primarily large volume, large residence time and cold temperatures) compared to the lower lakes and increased recent inputs are not needed to explain the measured values.

  1. In-Lake Processes Offset Increased Terrestrial Inputs of Dissolved Organic Carbon and Color to Lakes

    Köhler, Stephan J.; Kothawala, Dolly; Futter, Martyn N.; Liungman, Olof; Tranvik, Lars


    Increased color in surface waters, or browning, can alter lake ecological function, lake thermal stratification and pose difficulties for drinking water treatment. Mechanisms suggested to cause browning include increased dissolved organic carbon (DOC) and iron concentrations, as well as a shift to more colored DOC. While browning of surface waters is widespread and well documented, little is known about why some lakes resist it. Here, we present a comprehensive study of Mälaren, the third largest lake in Sweden. In Mälaren, the vast majority of water and DOC enters a western lake basin, and after approximately 2.8 years, drains from an eastern basin. Despite 40 years of increased terrestrial inputs of colored substances to western lake basins, the eastern basin has resisted browning over this time period. Here we find the half-life of iron was far shorter (0.6 years) than colored organic matter (A420 ; 1.7 years) and DOC as a whole (6.1 years). We found changes in filtered iron concentrations relate strongly to the observed loss of color in the western basins. In addition, we observed a substantial shift from colored DOC of terrestrial origin, to less colored autochthonous sources, with a substantial decrease in aromaticity (-17%) across the lake. We suggest that rapid losses of iron and colored DOC caused the limited browning observed in eastern lake basins. Across a wider dataset of 69 Swedish lakes, we observed greatest browning in acidic lakes with shorter retention times (< 1.5 years). These findings suggest that water residence time, along with iron, pH and colored DOC may be of central importance when modeling and projecting changes in brownification on broader spatial scales. PMID:23976946

  2. Analysis of Gas Membrane Ultra-High Purification of Small Quantities of Mono-Isotopic Silane

    de Almeida, Valmor F. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Chemical Sciences Division; Hart, Kevin J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Chemical Sciences Division


    A small quantity of high-value, crude, mono-isotopic silane is a prospective gas for a small-scale, high-recovery, ultra-high membrane purification process. This is an unusual application of gas membrane separation for which we provide a comprehensive analysis of a simple purification model. The goal is to develop direct analytic expressions for estimating the feasibility and efficiency of the method, and guide process design; this is only possible for binary mixtures of silane in the dilute limit which is a somewhat realistic case. Among the common impurities in crude silane, methane poses a special membrane separation challenge since it is chemically similar to silane. Other potential problematic surprises are: ethylene, diborane and ethane (in this order). Nevertheless, we demonstrate, theoretically, that a carefully designed membrane system may be able to purify mono-isotopic, crude silane to electronics-grade level in a reasonable amount of time and expenses. We advocate a combination of membrane materials that preferentially reject heavy impurities based on mobility selectivity, and light impurities based on solubility selectivity. We provide estimates for the purification of significant contaminants of interest. To improve the separation selectivity, it is advantageous to use a permeate chamber under vacuum, however this also requires greater control of in-leakage of impurities in the system. In this study, we suggest cellulose acetate and polydimethylsiloxane as examples of membrane materials on the basis of limited permeability data found in the open literature. We provide estimates on the membrane area needed and priming volume of the cell enclosure for fabrication purposes when using the suggested membrane materials. These estimates are largely theoretical in view of the absence of reliable experimental data for the permeability of silane. Last but not least, future extension of this work to the non-dilute limit may apply to the recovery of silane from

  3. Analysis of Gas Membrane Ultra-High Purification of Small Quantities of Mono-Isotopic Silane

    de Almeida, Valmor F [ORNL; Hart, Kevin J [ORNL


    A small quantity of high-value, crude, mono-isotopic silane is a prospective gas for a small-scale, high-recovery, ultra-high membrane purification process. This is an unusual application of gas membrane separation for which we provide a comprehensive analysis of a simple purification model. The goal is to develop direct analytic expressions for estimating the feasibility and efficiency of the method, and guide process design; this is only possible for binary mixtures of silane in the dilute limit which is a somewhat realistic case. Among the common impurities in crude silane, methane poses a special membrane separation challenge since it is chemically similar to silane. Other potential problematic surprises are: ethylene, diborane and ethane (in this order). Nevertheless, we demonstrate, theoretically, that a carefully designed membrane system may be able to purify mono-isotopic, crude silane to electronics-grade level in a reasonable amount of time and expenses. We advocate a combination of membrane materials that preferentially reject heavy impurities based on mobility selectivity, and light impurities based on solubility selectivity. We provide estimates for the purification of significant contaminants of interest. To improve the separation selectivity, it is advantageous to use a permeate chamber under vacuum, however this also requires greater control of in-leakage of impurities in the system. In this study, we suggest cellulose acetate and polydimethylsiloxane as examples of membrane materials on the basis of limited permeability data found in the open literature. We provide estimates on the membrane area needed and priming volume of the cell enclosure for fabrication purposes when using the suggested membrane materials. These estimates are largely theoretical in view of the absence of reliable experimental data for the permeability of silane. Last but not least, future extension of this work to the non-dilute limit may apply to the recovery of silane from

  4. Recent desiccation of Western Great Basin Saline Lakes: Lessons from Lake Abert, Oregon, U.S.A.

    Moore, Johnnie N


    Although extremely important to migrating waterfowl and shorebirds, and highly threatened globally, most saline lakes are poorly monitored. Lake Abert in the western Great Basin, USA, is an example of this neglect. Designated a critical habitat under the Western Hemisphere Shorebird Reserve Network, the lake is at near record historic low levels and ultra-high salinities that have resulted in ecosystem collapse. Determination of the direct human effects and broader climate controls on Lake Abert illustrates the broader problem of saline lake desiccation and suggests future solutions for restoration of key habitat values. A 65-year time series of lake area was constructed from Landsat images and transformed to lake volume and salinity. "Natural" (without upstream withdrawals) conditions were calculated from climate and stream flow data, and compared to measured volume and salinity. Under natural conditions the lake would have higher volume and lower salinities because annual water withdrawals account for one-third of mean lake volume. Without withdrawals, the lake would have maintained annual mean salinities mostly within the optimal range of brine shrimp and alkali fly growth. Even during the last two years of major drought, the lake would have maintained salinities well below measured values. Change in climate alone would not produce the recent low lake volumes and high salinities that have destroyed the brine shrimp and alkali fly populations and depleted shorebird use at Lake Abert. Large scale withdrawal of water for direct human use has drastically increased the imbalance between natural runoff and evaporation during periods of drought in saline lakes worldwide but could be offset by establishing an "environmental water budget" to lay a foundation for the conservation of saline lake habitats under continued threats from development and climate change.

  5. Evaluation of methods to estimate lake herring spawner abundance in Lake Superior

    Yule, D.L.; Stockwell, J.D.; Cholwek, G.A.; Evrard, L.M.; Schram, S.; Seider, M.; Symbal, M.


    Historically, commercial fishers harvested Lake Superior lake herring Coregonus artedi for their flesh, but recently operators have targeted lake herring for roe. Because no surveys have estimated spawning female abundance, direct estimates of fishing mortality are lacking. The primary objective of this study was to determine the feasibility of using acoustic techniques in combination with midwater trawling to estimate spawning female lake herring densities in a Lake Superior statistical grid (i.e., a 10′ latitude × 10′ longitude area over which annual commercial harvest statistics are compiled). Midwater trawling showed that mature female lake herring were largely pelagic during the night in late November, accounting for 94.5% of all fish caught exceeding 250 mm total length. When calculating acoustic estimates of mature female lake herring, we excluded backscattering from smaller pelagic fishes like immature lake herring and rainbow smelt Osmerus mordax by applying an empirically derived threshold of −35.6 dB. We estimated the average density of mature females in statistical grid 1409 at 13.3 fish/ha and the total number of spawning females at 227,600 (95% confidence interval = 172,500–282,700). Using information on mature female densities, size structure, and fecundity, we estimate that females deposited 3.027 billion (109) eggs in grid 1409 (95% confidence interval = 2.356–3.778 billion). The relative estimation error of the mature female density estimate derived using a geostatistical model—based approach was low (12.3%), suggesting that the employed method was robust. Fishing mortality rates of all mature females and their eggs were estimated at 2.3% and 3.8%, respectively. The techniques described for enumerating spawning female lake herring could be used to develop a more accurate stock–recruitment model for Lake Superior lake herring.

  6. Survey and assessment of post volcanic activities of a young caldera lake, Lake Cuicocha, Ecuador

    G. Gunkel


    Full Text Available Cuicocha is a young volcano adjacent to the inactive Pleistocene Cotacachi volcano complex, located in the western cordilleras of the Ecuadorian Andes. A series of eruptions with intensive ash emission and collapse of the caldera occurred around 4500–3000 y BP. A crater 3.2 km in diameter and a maximum depth of 450 m was formed. Further eruptions of the volcano occurred 1300 y BP and formed four smaller domes within the caldera. Over the last few hundred years, a caldera lake has developed, with a maximum depth of 148 m. The lake water is characterized by sodium carbonate with elevated concentrations of manganese, calcium and chloride. Nowadays, an emission of gases, mainly CO2, and an input of warm spring water occur in Lake Cuicocha. The zone of high activity is in the western basin of the lake at a depth of 78 m, and continuous gas emissions with sediment resuspension were observed using sonar. In the hypolimnion of the lake, CO2 accumulation occurs up to 0.2% saturation, but the risk of a limnic eruption can be excluded at present. The lake possesses monomictic stratification behaviour, and during overturn an intensive gas exchange with the atmosphere occurs. Investigations concerning the sedimentation processes of the lake suggest only a thin sediment layer of up to 10–20 cm in the deeper lake basin; in the western bay, in the area of gas emissions, the lake bottom is partly depleted of sediment in the form of holes, and no lake colmation exists. Decreases in the lake water level of about 30 cm y−1 indicate a percolation of water into fractures and fissures of the volcano, triggered by a nearby earthquake in 1987.

  7. The "tipping" temperature within Subglacial Lake Ellsworth, West Antarctica and its implications for lake access

    M. Thoma


    Full Text Available We present results from new geophysical data allowing 3-D modelling of the water flow within Subglacial Lake Ellsworth (SLE, West Antarctica. Our simulations indicate that this lake has a novel temperature distribution due to significantly thinner ice than other surveyed subglacial lakes. The critical pressure boundary (tipping depth, established from the semi-empirical Equation of State, defines whether the lake's flow regime is convective or stratified. It passes through SLE and separates different temperature (and flow regimes on either side of the lake. Our results have implications for the location of proposed access holes into SLE, the choice of which will depend on scientific or operational priorities. If an understanding of subglacial lake water properties and dynamics is the priority, holes are required in a basal freezing area at the North end of the lake. This would be the preferred priority suggested by this paper, requiring temperature and salinity profiles in the water column. A location near the Southern end, where bottom currents are lowest, is optimum for detecting the record of life in the bed sediments; to minimise operational risk and maximise the time span of a bed sediment core, a location close to the middle of the lake, where the basal interface is melting and the lake bed is at its deepest, remains the best choice. Considering potential lake-water salinity and ice-density variations, we estimate the critical tipping depth, separating different temperature regimes within subglacial lakes, to be in about 2900 to 3045 m depth.

  8. RADARSAT-2 Polarimetry for Lake Ice Mapping

    Pan, Feng; Kang, Kyung-Kuk; Duguay, Claude


    Changes in the ice regime of lakes can be employed to assess long-term climate trends and variability in high latitude regions. Lake ice cover observations are not only useful for climate monitoring, but also for improving ice and weather forecasts using numerical prediction models. In recent years, satellite remote sensing has assumed a greater role in observing lake ice cover for both purposes. Radar remote sensing has become an essential tool for mapping lake ice at high latitudes where cloud cover and polar darkness severely limits ice observations from optical systems. In Canada, there is an emerging interest by government agencies to evaluate the potential of fully polarimetric synthetic aperture radar (SAR) data from RADARSAT-2 (C-band) for lake ice monitoring. In this study, we processed and analyzed the polarization states and scattering mechanisms of fully polarimetric RADARSAT-2 data obtained over Great Bear Lake, Canada, to identify open water and different ice types during the freeze-up and break-up periods. Polarimetric decompositions were employed to separate polarimetric measurements into basic scattering mechanisms. Entropy, anisotropy, and alpha angle were derived to characterize the scattering heterogeneity and mechanisms. Ice classes were then determined based on entropy and alpha angle using the unsupervised Wishart classifier and results evaluated against Landsat 8 imagery. Preliminary results suggest that the RADARSAT-2 polarimetric data offer a strong capability for identifying open water and different lake ice types.

  9. Water balance for Crater Lake, Oregon

    Nathenson, Manuel


    A water balance for Crater Lake, Oregon, is calculated using measured lake levels and precipitation data measured at Park Headquarters and at a gage on the North Rim. Total water supply to the lake from precipitation and inflow from the crater walls is found to be 224 cm/y over the area of the lake. The ratio between water supply to the lake and precipitation at Park Headquarters is calculated as 1.325. Using leakage determined by Phillips (1968) and Redmond (1990), evaporation from the lake is approximately 85 cm/y. Calculations show that water balances with precipitation data only from Park Headquarters are unable to accurately define the water-level variation, whereas the addition of yearly precipitation data from the North Rim reduces the average absolute deviation between calculated and modeled water levels by one half. Daily precipitation and water-level data are modeled assuming that precipitation is stored on the rim as snow during fall and winter and released uniformly during the spring and early summer. Daily data do not accurately define the water balance, but they suggest that direct precipitation on the lake is about 10 % higher than that measured at Park Headquarters and that about 17 % of the water supply is from inflow from the rim.

  10. Insights from a synthesis of old and new climate-proxy data from the Pyramid and Winnemucca lake basins for the period 48 to 11.5 cal ka

    Benson, Larry; Smoot, J.P.; Lund, S.P.; Mensing, S.A.; Foit, F.F.; Rye, R.O.


    A synthesis of old and new paleoclimatic data from the Pyramid and Winnemucca lake basins indicates that, between 48.0 and 11.5·103 calibrated years BP (hereafter ka), the climate of the western Great Basin was, to a degree, linked with the climate of the North Atlantic. Paleomagnetic secular variation (PSV) records from Pyramid Lake core PLC08-1 were tied to the GISP2 ice-core record via PSV matches to North Atlantic sediment cores whose isotopic and(or) carbonate records could be linked to the GISP2 δ18O record. Relatively dry intervals in the western Great Basin were associated with cold Heinrich events and relatively wet intervals were associated with warm Dansgaard-Oeschger (DO) oscillations. The association of western Great Basin dry events with North Atlantic cold events (and vice versa) switched sometime after the Laurentide Ice Sheet (LIS) reached its maximum extent. For example, the Lahontan highstand, which culminated at 15.5 ka, and a period of elevated lake level between 13.1 and 11.7 ka were associated with cold North Atlantic conditions, the latter period with the Youngest Dryas event. Relatively dry periods were associated with the Bølling and Allerød warm events. A large percentage of the LIS may have been lost to the North Atlantic during Heinrich events 1 and 2 and may have resulted in the repositioning of the Polar Jet Stream over North America. The Trego Hot Springs, Wono, Carson Sink, and Marble Bluff tephras found in core PLC08-1 have been assigned GISP2 calendar ages of respectively, 29.9, 33.7, 34.1, and 43.2 ka. Given its unique trace-element chemistry, the Carson Sink Bed is the same as Wilson Creek Ash 15 in the Mono Lake Basin. This implies that the Mono Lake magnetic excursion occurred at approximately 34 ka and it is not the Laschamp magnetic excursion. The entrance of the First Americans into the northern Great Basin is dated to approximately 14.4 ka, a time when the climate was relatively dry. Evidence for human occupation of

  11. Evaluation of offshore stocking of Lake Trout in Lake Ontario

    Lantry, B.F.; O'Gorman, R.; Strang, T.G.; Lantry, J.R.; Connerton, M.J.; Schanger, T.


    Restoration stocking of hatchery-reared lake trout Salvelinus namaycush has occurred in Lake Ontario since 1973. In U.S. waters, fish stocked through 1990 survived well and built a large adult population. Survival of yearlings stocked from shore declined during 1990–1995, and adult numbers fell during 1998–2005. Offshore stocking of lake trout was initiated in the late 1990s in response to its successful mitigation of predation losses to double-crested cormorants Phalacrocorax auritus and the results of earlier studies that suggested it would enhance survival in some cases. The current study was designed to test the relative effectiveness of three stocking methods at a time when poststocking survival for lake trout was quite low and losses due to fish predators was a suspected factor. The stocking methods tested during 2000–2002 included May offshore, May onshore, and June onshore. Visual observations during nearshore stockings and hydroacoustic observations of offshore stockings indicated that release methods were not a direct cause of fish mortality. Experimental stockings were replicated for 3 years at one site in the southwest and for 2 years at one site in the southeast. Offshore releases used a landing craft to transport hatchery trucks from 3 to 6 km offshore out to 55–60-m-deep water. For the southwest site, offshore stocking significantly enhanced poststocking survival. Among the three methods, survival ratios were 1.74 : 1.00 : 1.02 (May offshore : May onshore : June onshore). Although not statistically significant owing to the small samples, the trends were similar for the southeast site, with survival ratios of 1.67 : 1.00 : 0.72. Consistent trends across years and sites indicated that offshore stocking of yearling lake trout during 2000–2002 provided nearly a twofold enhancement in survival; however, this increase does not appear to be great enough to achieve the 12-fold enhancement necessary to return population abundance to restoration

  12. Mono-jet signatures of gluphilic scalar dark matter

    Godbole, Rohini M.; Mendiratta, Gaurav; Shivaji, Ambresh; Tait, Tim M. P.


    A gluphilic scalar dark matter (GSDM) model has recently been proposed as an interesting vision for WIMP dark matter communicating dominantly with the Standard Model via gluons. We discuss the collider signature of a hard jet recoiling against missing momentum (;mono-jet;) in such a construction, whose leading contribution is at one-loop. We compare the full one-loop computation with an effective field theory (EFT) treatment, and find (as expected) that EFT does not accurately describe regions of parameter space where mass of the colored mediator particles are comparable to the experimental cuts on the missing energy. We determine bounds (for several choices of SU(3) representation of the mediator) from the √{ s} = 8 TeV data, and show the expected reach of the √{ s} = 13 TeV LHC and a future 100 TeV pp collider to constrain or discover GSDM models.

  13. Aryl hydrocarbon mono-oxygenase activity in human lymphocytes

    Griffin, G.D.; Schuresko, D.D.


    Aryl hydrocarbon mono-oxygenase (AHM), an enzyme of key importance in metabolism of xenobiotic chemicals such as polynuclear aromatic hydrocarbons (PNA), is present in human lymphocytes. Studies investing the relation of activity of AHM in human lymphocytes to parameters such as disease state, PNA exposure, in vitro mitogen stimulation, etc. have been summarized in this report. Some studies have demonstrated increased AHM activity in lymphocytes from cigarette smokers (compared to nonsmokers), and in lung cancer patients when compared to appropriate control groups. These observations are confused by extreme variability in human lymphocyte AHM activities, such variability arising from factors such as genetic variation in AHM activity, variation in in vitro culture conditions which affect AHM activity, and the problematical relationship of common AHM assays to actual PNA metabolism taking place in lymphocytes. If some of the foregoing problems can be adequately addressed, lymphocyte AHM activity could hold the promise of being a useful biomarker system for human PNA exposure.

  14. Mono-jet Signatures of Gluphilic Scalar Dark Matter

    Godbole, Rohini M; Shivaji, Ambresh; Tait, Tim M P


    A gluphilic scalar dark matter (GSDM) model has recently been proposed as an interesting vision for WIMP dark matter communicating dominantly with the Standard Model via gluons. We discuss the collider signature of a hard jet recoiling against missing momentum ("mono-jet") in such a construction, whose leading contribution is at one-loop. We compare the full one-loop computation with an effective field theory (EFT) treatment, and find (as expected) that EFT does not accurately describe regions of parameter space where mass of the colored mediator particles are comparable to the experimental cuts on the missing energy. We determine bounds (for several choices of SU(3) representation of the mediator) from the $\\sqrt{s}=$ 8 TeV data, and show the expected reach of the $\\sqrt{s}=$ 13 TeV LHC and a future 100 TeV $pp$ collider to constrain or discover GSDM models.

  15. Mechanically flexible optically transparent porous mono-crystalline silicon substrate

    Rojas, Jhonathan Prieto


    For the first time, we present a simple process to fabricate a thin (≥5μm), mechanically flexible, optically transparent, porous mono-crystalline silicon substrate. Relying only on reactive ion etching steps, we are able to controllably peel off a thin layer of the original substrate. This scheme is cost favorable as it uses a low-cost silicon <100> wafer and furthermore it has the potential for recycling the remaining part of the wafer that otherwise would be lost and wasted during conventional back-grinding process. Due to its porosity, it shows see-through transparency and potential for flexible membrane applications, neural probing and such. Our process can offer flexible, transparent silicon from post high-thermal budget processed device wafer to retain the high performance electronics on flexible substrates. © 2012 IEEE.

  16. Mono-jet signatures of gluphilic scalar dark matter

    Rohini M. Godbole


    Full Text Available A gluphilic scalar dark matter (GSDM model has recently been proposed as an interesting vision for WIMP dark matter communicating dominantly with the Standard Model via gluons. We discuss the collider signature of a hard jet recoiling against missing momentum (“mono-jet” in such a construction, whose leading contribution is at one-loop. We compare the full one-loop computation with an effective field theory (EFT treatment, and find (as expected that EFT does not accurately describe regions of parameter space where mass of the colored mediator particles are comparable to the experimental cuts on the missing energy. We determine bounds (for several choices of SU(3 representation of the mediator from the s=8 TeV data, and show the expected reach of the s=13 TeV LHC and a future 100 TeV pp collider to constrain or discover GSDM models.

  17. Lake retention of manufactured nanoparticles

    Koelmans, A.A.; Quik, J.T.K.; Velzeboer, I.


    For twenty-five world lakes and three engineered nanoparticles (ENP), lake retention was calculated using a uniformly mixed lake mass balance model. This follows similar approaches traditionally used in water quality management. Lakes were selected such that lake residence times, depths and areal hy

  18. Lake retention of manufactured nanoparticles

    Koelmans, A.A.; Quik, J.T.K.; Velzeboer, I.


    For twenty-five world lakes and three engineered nanoparticles (ENP), lake retention was calculated using a uniformly mixed lake mass balance model. This follows similar approaches traditionally used in water quality management. Lakes were selected such that lake residence times, depths and areal hy

  19. Detecting Magnetosomes in Freshwater Lakes and Lake Sediments

    Kodama, K. P.; Kim, B.; Kopp, B.; Chen, A. P.


    We will present a summary of the work done to date on detecting magnetosomes in the lake sediments and water column of Lake Ely, a small post-glacial lake in northeastern Pennsylvania. To establish that magnetosomes dominate the magnetic mineralogy of the Lake Ely sediments we sampled the water column every meter down to its maximum depth of 23 m and measured the dissolved oxygen, sulfide, and iron, as well as the ARM of the material filtered from the water. We examined the water samples for magnetotactic bacteria. These results established an increase in the ARM of the filtered material at the oxic-anoxic transition. They also showed that the ARM was carried by magnetosomes produced by magnetotactic bacteria living in the water column at depths from 15-19 m. TEM of magnetic separates collected from the lake sediments show that magnetosomes are transferred to the sediments from the water column and are a significant fraction of the magnetic minerals in the sediments. We used a variety of mineral magnetic techniques to magnetically characterize the magnetosomes in the lake sediments. The delta-delta ratio test of low temperature behavior at the Verwey transition (Moskowitz et al., 1993) gave values of 1.2 to 1.5, lower than the theoretically predicted level of 2 for magnetosomes, but a numeric unmixing technique could resolve higher delta-delta ratios in the dark organic-rich layers in the sediments where magnetosomes were more prevalent. ARM/SIRM ratios of 0.15 to 0.35 with Raf values (the crossover of an IRM acquisition curve versus its alternating field demagnetization curve) of 0.45 to 0.5 are consistent with the presence of magnetosomes in the sediments, the water column, and in a sediment trap located at the bottom of the lake. IRM and ARM acquisition modeling of samples collected from a 160 cm piston core revealed two components of magnetization with coercivities of about 25 mT and 65 mT that are identified as Egli's (2004) biogenic soft (BS) and biogenic

  20. Synthesis and Photocytotoxicity of Mono-functionalised Porphyrin with Valine Moiety

    Wei Min SHI; Jian WU; Yi Feng WU; Kai Xian QIAN


    A mono-funtionalised tetraphenylporphyrin (TPP) bearing valine moiety at the phenyl ring was synthesized for photocytotoxicity examination in four steps, starting from regiospecific mono-nitration of TPP at the phenyl ring. The in vitro photocytotoxicitic effect against SPC-A1 adenocarcinona cell line was tested.

  1. Growth and survival of stocked lake trout with nuclear cataracts in Lake Ontario

    Kincaid, Harold L.; Elrod, Joseph H.


    Four strains of yearling lake trout Salvelinus namaycush from the 1985 and 1986 year-classes at the Allegheny National Fish Hatchery were evaluated for nuclear cataracts prior to stocking in Lake Ontario in June 1986 and 1987. Lake trout recaptured by bottom trawling from April to August 1987 and 1988 were examined for cataracts. Cataract frequencies in three strains of yearling lake trout at stocking in 1986 and after 14 and 26 months in the lake were: Seneca Lake–35, 24, and 29%; Lake Ontario–32,24, and 42%; and Lake Superior–7,4, and 6%. Cataract frequencies for yearlings at stocking in 1987 and after 2 and 14 months were: Seneca Lake–51, 37, and 51 %; Lake Superior–7,12, and 12%; and Jenny Lake–46,13, and 36%. Cataract frequency was lower (P weight and length were not different between healthy fish and fish with cataracts. The absence of growth depression in fish with cataracts and the reduced survival rate suggested that faster growing fish were more susceptible to cataract formation.

  2. Salting our freshwater lakes.

    Dugan, Hilary A; Bartlett, Sarah L; Burke, Samantha M; Doubek, Jonathan P; Krivak-Tetley, Flora E; Skaff, Nicholas K; Summers, Jamie C; Farrell, Kaitlin J; McCullough, Ian M; Morales-Williams, Ana M; Roberts, Derek C; Ouyang, Zutao; Scordo, Facundo; Hanson, Paul C; Weathers, Kathleen C


    The highest densities of lakes on Earth are in north temperate ecosystems, where increasing urbanization and associated chloride runoff can salinize freshwaters and threaten lake water quality and the many ecosystem services lakes provide. However, the extent to which lake salinity may be changing at broad spatial scales remains unknown, leading us to first identify spatial patterns and then investigate the drivers of these patterns. Significant decadal trends in lake salinization were identified using a dataset of long-term chloride concentrations from 371 North American lakes. Landscape and climate metrics calculated for each site demonstrated that impervious land cover was a strong predictor of chloride trends in Northeast and Midwest North American lakes. As little as 1% impervious land cover surrounding a lake increased the likelihood of long-term salinization. Considering that 27% of large lakes in the United States have >1% impervious land cover around their perimeters, the potential for steady and long-term salinization of these aquatic systems is high. This study predicts that many lakes will exceed the aquatic life threshold criterion for chronic chloride exposure (230 mg L(-1)), stipulated by the US Environmental Protection Agency (EPA), in the next 50 y if current trends continue.


    Elliott, James E.; Avery, Dale W.


    A mineral survey of the Dolus Lakes Roadless Area in southwestern Montana, was conducted. Much of the roadless area has probable and substantiated potential for resources of gold, silver, molybdenum, and tungsten. The nature of the geologic terrain indicates that there is little promise for the occurrence of coal, oil, gas, or geothermal resources. Detailed geologic and geochemical studies are suggested to delineate exploration targets that could be tested by drilling.

  4. Evolutionary history of a widespread tree species Acer mono in East Asia.

    Guo, Xi-Di; Wang, Hong-Fang; Bao, Lei; Wang, Tian-Ming; Bai, Wei-Ning; Ye, Jun-Wei; Ge, Jian-Ping


    East Asia has the most diverse temperate flora in the world primarily due to the lack of Pleistocene glaciation and the geographic heterogeneity. Although increasing phylogeography studies in this region provided more proofs in this issue, discrepancies and uncertainty still exist, especially in northern temperate deciduous broad-leaved and coniferous mixed forest region (II). And a widespread plant species could reduce the complexity to infer the relationship between diversity and physiographical pattern. Hence, we studied the evolution history of a widespread temperate tree, Acer mono, populations in region II and the influence of physiographic patterns on intraspecific genetic diversity. Analyses of chloroplast sequences and nuclear microsatellites indicated high levels of genetic diversity. The diversity distribution was spatially heterogeneous and a latitudinal cline existed in both markers. The spatial distribution pattern between genetic diversity within A. mono and the diversity at species level was generally consistent. Western subtropical evergreen broad-leaved forest subregion (IVb) had a unique ancient chloroplast clade (CP3) and a nuclear gene pool (GP5) with dominance indicating the critical role of this area in species diversification. Genetic data and ecological niche model results both suggested that populations in region II disappeared during the last glacial maximum (LGM) and recovered from south of Changbai Mt. and the Korean Peninsula. Two distribution centers were likely during the LGM, one in the north edge of warm temperate deciduous broad-leaved forest region (III) and another in the south edge of region III. This was reflected by the genetic pattern with two spatially independent genetic groups. This study highlights the key role of region III in sustaining genetic diversity in the northern range and connecting diversity between southern and northern range. We elucidated the diversity relationship between vegetation regions which could

  5. Collide and Conquer: Constraints on Simplified Dark Matter Models using Mono-X Collider Searches

    Brennan, A J; Gramling, J; Jacques, T D


    The use of simplified models as a tool for interpreting dark matter collider searches has become increasingly prevalent, and while early Run II results are beginning to appear, we look to see what further information can be extracted from the Run I dataset. We consider three `standard' simplified models that couple quarks to fermionic singlet dark matter: an $s$-channel vector mediator with vector or axial-vector couplings, and a $t$-channel scalar mediator. Upper limits on the couplings are calculated and compared across three alternate channels, namely mono-jet, mono-$Z$ (leptonic) and mono-$W/Z$ (hadronic). The strongest limits are observed in the mono-jet channel, however the computational simplicity and absence of significant $t$-channel model width effects in the mono-boson channels make these a straightforward and competitive alternative. We also include a comparison with relic density and direct detection constraints.

  6. Aluminum substitution in goethite in lake ore

    Carlson, L.


    Full Text Available The extent of substitution of Fe by Al in goethite in 32 lake ore samples collected from 11 lakes in Finland varied between 0 and 23 mol-%. The data indicated a negative relationship between Al-substitution and the particle size of lake ore. Differences in the Al-substitution were apparent between sampling sites, suggesting that kinetic and environmental variation in lake ore formation influences the substitution. Non-substituted goethite is formed in coarse-grained sediments with locally high concentrations of Fe due to iron-rich springs. Unit cell edge lengths and volumes of goethite varied as function of Al-subsitution but deviated from the Vegard relationship towards higher values.

  7. 2016 Lake Michigan Lake Trout Working Group Report

    Madenjian, Charles P.; Breidert, Brian; Boyarski, David; Bronte, Charles R.; Dickinson, Ben; Donner, Kevin; Ebener, Mark P.; Gordon, Roger; Hanson, Dale; Holey, Mark; Janssen, John; Jonas, Jory; Kornis, Matthew; Olsen, Erik; Robillard, Steve; Treska, Ted; Weldon, Barry; Wright, Greg D.


    This report provides a review on the progression of lake trout rehabilitation towards meeting the Salmonine Fish Community Objectives (FCOs) for Lake Michigan (Eshenroder et. al. 1995) and the interim goal and evaluation objectives articulated in A Fisheries Management Implementation Strategy for the Rehabilitation of Lake Trout in Lake Michigan (Dexter et al. 2011); we also include data describing lake trout stocking and mortality to portray the present state of progress towards lake trout rehabilitation.

  8. Morphological diversity of mole vole mono- and polymorphic populations: Does Chernov's "compensation principle" work within a population?

    Vasil'ev, A G; Bolshakov, V N; Evdokimov, N G; Sineva, N V


    The ecological "compensation principle" enunciated by Yu.I. Chernov, who suggested a higher level of compensatory diversity in communities depleted in composition, proved to be also applicable to a single population, as demonstrated in a model rodent species, mole vole with mono- and polymorphic coat color, using the methods of geometric morphometrics. The mandible shape diversity was significantly increased in the monomorphic as compared to polymorphic populations, in which the division of foraging activities between animals of different morphs led to a suppression of general morphological diversity.

  9. Multi-proxy identification of the Laschamp geomagnetic field excursion in Lake Pupuke, New Zealand

    Nilsson, Andreas; Muscheler, Raimund; Snowball, Ian; Aldahan, Ala; Possnert, Göran; Augustinus, Paul; Atkin, Daniel; Stephens, Tom


    We present palaeomagnetic and cosmogenic radionuclide records of the Laschamp geomagnetic excursion in Lake Pupuke, a maar lake in Auckland, New Zealand. Laschamp was identified by a combination of relative palaeointensity, 10Be and 14C data from the lake sediments and represents the first such record from the Southern Hemisphere. Despite the high organic carbon content, which causes relatively weak natural remanent magnetisations, the geomagnetic intensity minimum associated with the Laschamp excursion is identifiable as a relative palaeointensity minimum that is synchronous with (i) a peak in 10Be concentration and (ii) an anomaly in Δ 14C. The Lake Pupuke time scale, provided by 14C data calibrated with INTCAL09, places the 10Be maximum at the same time as a 10Be maximum in Greenland ice cores when secured to the GICC05 time scale. The central age of the Laschamp geomagnetic excursion in Lake Pupuke as defined by the 10Be prediction peak is c. 41 kyr, which confirms its global application as a palaeomagnetic isochron. Anomalous palaeomagnetic directional data at c. 32 kyr in the Lake Pupuke sediments may represent the Mono Lake geomagnetic excursion, but tephra layers caused by frequent eruptions in the Auckland volcanic field during this excursion probably disrupted the palaeointensity signal. The study highlights the value of combining traditional palaeomagnetic methods with measurements of cosmogenic radionuclides in the quest for accurate and precise geochronologies during MIS3, a time of rapid global climate change.

  10. The Current State of China's Freshwater Resources and Related Suggestions

    Wu Ruijin


    China has many lakes, marshlands and rivers. Due to their uneven geographical distribution and varied degrees of salinity, their exploitable freshwater resources are limited. In the wake of the highspeed growth of national economy in recent years, human infringement upon their natural settings has been increasingly intense, leading to the degeneration of China's lacustrine ecosystems and the degradation of their surrounding environments. Lakes are shrinking and becoming more saline. In arid and semi-arid inland areas, some of them have even disappeared. In addition, lake water pollution and eutrophication in densely populated areas are getting worse, resulting in serious water shortages in some places. Silt deposition in lake basins, water surface shrinkage caused by hectic and irrational reclamation for farmland, the prevalence of flooding and water-logging calamities and ecosystem depletion caused by predatory exploitation of fishery resources, all of these have become restrictive factors in regional sustainable development. The author of this article suggests measures for the protection and sustainable exploitation of limnetic settings in China.

  11. Hydrography - Lakes Assessments - Non Attaining

    NSGIC GIS Inventory (aka Ramona) — This layer shows only non attaining lakes of the Integrated List. The Lakes Integrated List represents lake assessments in an integrated format for the Clean Water...

  12. Boat Dwellers of Weishan Lake



    IN the south of Shandong Province, Weishan Lake is the largest freshwater lake in northern China. Under the bright blue sky, it gleams like a large mirror. "As the sun is about to set, Weishan Lake is quiet…" Humming

  13. Nitrogen deposition to lakes in national parks of the western Great Lakes region: Isotopic signatures, watershed retention, and algal shifts

    Hobbs, William O.; Lafrancois, Brenda Moraska; Stottlemyer, Robert; Toczydlowski, David; Engstrom, Daniel R.; Edlund, Mark B.; Almendinger, James E.; Strock, Kristin E.; VanderMeulen, David; Elias, Joan E.; Saros, Jasmine E.


    Atmospheric deposition is a primary source of reactive nitrogen (Nr) to undisturbed watersheds of the Great Lakes region of the U.S., raising concerns over whether enhanced delivery over recent decades has affected lake ecosystems. The National Atmospheric Deposition Program (NADP) has been measuring Nr deposition in this region for over 35 years. Here we explore the relationships among NADP-measured Nr deposition, nitrogen stable isotopes (δ15N) in lake sediments, and the response of algal communities in 28 lakes situated in national parks of the western Great Lakes region of the U.S. We find that 36% of the lakes preserve a sediment δ15N record that is statistically correlated with some form of Nr deposition (total dissolved inorganic N, nitrate, or ammonium). Furthermore, measured long-term (since 1982) nitrogen biogeochemistry and inferred critical nitrogen loads suggest that watershed nitrogen retention and climate strongly affect whether sediment δ15N is related to Nr deposition in lake sediment records. Measurements of algal change over the last ~ 150 years suggest that Nr deposition, in-lake nutrient cycling, and watershed inputs are important factors affecting diatom community composition, in addition to direct climatic effects on lake physical limnology. The findings suggest that bulk sediment δ15N does reflect Nr deposition in some instances. In addition, this study highlights the interactive effects of Nr deposition and climate variability.

  14. Resveratrol induces cellular senescence with attenuated mono-ubiquitination of histone H2B in glioma cells

    Gao, Zhen; Xu, Michael S.; Barnett, Tamara L. [Nevada Cancer Institute, Las Vegas, NV 89135 (United States); Xu, C. Wilson, E-mail: [Nevada Cancer Institute, Las Vegas, NV 89135 (United States)


    Research highlights: {yields} Resveratrol induces cellular senescence in glioma cell. {yields} Resveratrol inhibits mono-ubiquitination of histone H2B at K120. {yields} Depletion of RNF20, phenocopies the inhibitory effects of resveratrol. {yields} Mono-ubiquitination of histone H2B at K120 is a novel target of resveratrol. {yields} RNF20 inhibits cellular senescence in proliferating glioma cells. -- Abstract: Resveratrol (3,4',5-trihydroxy-trans-stilbene), a polyphenol naturally occurring in grapes and other plants, has cancer chemo-preventive effects and therapeutic potential. Although resveratrol modulates multiple pathways in tumor cells, how resveratrol or its affected pathways converge on chromatin to mediate its effects is not known. Using glioma cells as a model, we showed here that resveratrol inhibited cell proliferation and induced cellular hypertrophy by transforming spindle-shaped cells to enlarged, irregular and flatten-shaped ones. We further showed that resveratrol-induced hypertrophic cells expressed senescence-associated-{beta}-galactosidase, suggesting that resveratrol-induced cellular senescence in glioma cells. Consistent with these observations, we demonstrated that resveratrol inhibited clonogenic efficiencies in vitro and tumor growth in a xenograft model. Furthermore, we found that acute treatment of resveratrol inhibited mono-ubiquitination of histone H2B at K120 (uH2B) in breast, prostate, pancreatic, lung, brain tumor cells as well as primary human cells. Chronic treatment with low doses of resveratrol also inhibited uH2B in the resveratrol-induced senescent glioma cells. Moreover, we showed that depletion of RNF20, a ubiquitin ligase of histone H2B, inhibited uH2B and induced cellular senescence in glioma cells in vitro, thereby recapitulated the effects of resveratrol. Taken together, our results suggest that uH2B is a novel direct or indirect chromatin target of resveratrol and RNF20 plays an important role in inhibiting cellular

  15. 21 CFR 582.4505 - Mono- and diglycerides of edible fats or oils, or edible fat-forming acids.


    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Mono- and diglycerides of edible fats or oils, or... GENERALLY RECOGNIZED AS SAFE Emulsifying Agents § 582.4505 Mono- and diglycerides of edible fats or oils, or edible fat-forming acids. (a) Product. Mono- and diglycerides of edible fats or oils, or edible...

  16. Human land uses enhance sediment denitrification and N2O production in Yangtze lakes primarily by influencing lake water quality

    W. Liu


    Full Text Available Sediment denitrification in lakes alleviates the effects of eutrophication through removal of nitrogen to the atmosphere as N2O and N2. However, N2O contributes notably to the greenhouse effect and global warming. Human lands uses (e.g., agricultural and urban areas strongly affect lake water quality and sediment characteristics, which, in turn, may regulate lake sediment denitrification and N2O production. In this study, we investigated sediment denitrification and N2O production and their relationships to within-lake variables and watershed land uses in 20 lakes from the Yangtze River basin in China. The results indicated that both lake water quality and sediment characteristics were significantly influenced by watershed land uses. Increased background denitrification rate would result in increased N2O production rate. Background denitrification and N2O production rates were positively related to water nitrogen concentrations but were not significantly correlated with sediment characteristics and plant community structure. A significant positive relationship was observed between background denitrification rate and percentage of human-dominated land uses (HDL in watersheds. Structural equation modelling revealed that the indirect effects of HDL on sediment denitrification and N2O production in Yangtze lakes were mediated primarily through lake water quality. Our findings also suggest that although sediments in Yangtze lakes can remove large quantities of nitrogen through denitrification, they may also be an important source of N2O, especially in lakes with high nitrogen content.

  17. Statistical analysis of interaction between lake seepage rates and groundwater and lake levels

    Ala-aho, P.; Rossi, P. M.; Klöve, B.


    measurement locations. Result suggested that underlying hydrogeological conditions dictated the variation of seepage rates to some extent for all of the measurement locations. Correlation analysis of seepage meter measurements and water levels and precipitation indicated that seepage rates in a specific seepage measurement location were influenced by different parts of the hydrogeological system. Location and rate of inseepage were dictated by a different groundwater flow system compared to locations where outseepage were measured. In addition locations of outseepage responded differently to changes in the lake and groundwater levels. Variation of seepage rate in some locations reflected the changes in the regional groundwater system, as other responded to changes in the local flow system. Study shows that a simple statistical analysis of temporal variability of lake seepage rates and lake and groundwater level recordings can give a valuable insight to the dynamics of lake - groundwater interaction. Such understanding is of crucial importance when effects of changes in climate, land use or water extraction needs to be understood and managed in lake - aquifer systems. ACKNOWLEDGEMENTS The project was financed by the 7th framework project GENESIS (226536).

  18. Bioaccumulation of toxaphene congeners in the lake superior food web

    Muir, D.C.G.; Whittle, D.M.; De Vault, D. S.; Bronte, C.R.; Karlsson, H.; Backus, S.; Teixeira, C.


    The bioaccumulation and biotransformation of toxaphene was examined in the food webs of Lake Superior and Siskiwit Lake (Isle Royale) using congener specific analysis as well as stable isotope ratios of carbon and nitrogen to characterize food webs. Toxaphene concentrations (calculated using technical toxaphene) in lake trout (Salvelinus namaycush) from the western basin of Lake Superior (N = 95) averaged (±SD) 889 ± 896 ng/g wet wt and 60 ± 34 ng/g wet wt in Siskiwit Lake. Major congeners in lake trout were B8-789 (P38), B8-2226 (P44), B9-1679 (P50), and B9-1025 (P62). Toxaphene concentrations were found to vary seasonally, especially in lower food web organisms in Lake Superior and to a lesser extent in Siskiwit Lake. Toxaphene concentrations declined significantly in lake herring (Coregonus artedii), rainbow smelt (Omerus mordax), and slimy sculpin (Cottus cognatus) as well as in zooplankton (> 102 &mn;m) and Mysis (Mysis relicta) between May and October. The seasonal variation may reflect seasonal shifts in the species abundance within the zooplankton community. Trophic magnification factors (TMF) derived from regressions of toxaphene congener concentrations versus δ15N were > 1 for most octa- and nonachlorobornanes in Lake Superior except B8-1413 (P26) and B9-715. Log bioaccumulation factors (BAFs) for toxaphene congeners in lake trout (ng/g lipid/ng/L dissolved) ranged from 4.54 to 9.7 and were significantly correlated with log octanol-water partition coefficients. TMFs observed for total toxaphene and congener B9-1679 in Lake Superior were similar to those in Arctic lakes, as well as to previous studies in the Great Lakes, which suggests that the bioaccumulation behavior of toxaphene is similar in pelagic food webs of large, cold water systems. However, toxaphene concentrations were lower in lake trout from Siskiwit Lake and lakes in northwestern Ontario than in Lake Superior possibly because of shorter food chains and greater reliance on zooplankton or

  19. Separation of mono- and di-PEGylate of exenatide and resolution of positional isomers of mono-PEGylates by preparative ion exchange chromatography.

    Nguyen, Ngoc-Thanh Thi; Lee, Jae Sun; Yun, Soi; Lee, E K


    Exenatide is a synthetic version of the 39-mer peptide of Exendin-4, which is an FDA-approved therapeutic against Type II diabetes mellitus. However, exenatide has a very short in-serum half-life and PEGylation have been performed to improve its in-serum stability. PEGylation often yields multivalent binding to non-specific residues, and the desired species should be carefully separated by chromatographies. In this study, we first devised an aqueous-phase, two-step PEGylation process. This consists of thiolation of Lys 12 and 27 residues followed by attachment of PEG-maleimide (10kD) to thiol groups. This process yields various species: mono-PEGylates with positional isomers, di-PEGylate, and other higher MW substances. A prep-grade cationic exchange chromatography (HiTrap SP) at pH 3.0 partially separated mono- and di-PEGylates based on the molar ratio of conjugated PEG and peptide and thus molecular weight of the conjugates. To further investigate the chromatographic separation of positional isomers of mono-PEGylates, we prepared two kinds of exenatide analogs by point mutation; K12C and K27C. Each analog was mono-PEGylated with very high yield (>95%). When a mixture of the two positional isomers of mono-PEGylates was applied to HiTrap SP chromatography, K12C-PEGylate and K27C-PEGylate eluted separately at 0.22M and 0.33M NaCl, respectively. When the proportions of acid and its conjugate base of the amino acid residues adjacent to the PEGylation site at pH 3.0 were analyzed, K27C-PEGylate shows stronger positive charge than K12C-PEGylate, and we propose the residence time difference between the two mono-PEGylates could be due to the charge difference. ELISA result shows that the immuno-binding activity of both analogs and their mono-PEGylates are well maintained. Furthermore, both mono-PEGylates of the analogs show higher than 50-fold improved anti-trypsin stability. We expect that mono-PEGylates of the exenatide analogs are alternatives to the conventional C40

  20. Modelled present and future thaw lake area expansion/contraction trends throughout the continuous permafrost zone

    Y. Mi


    Full Text Available Thaw lakes and drained lake basins are a dominant feature of Arctic lowlands. Thaw lakes are a source of the greenhouse gas methane (CH4, which is produced under anaerobic conditions, while drained lake basins are carbon sinks due to sedimentation. Besides feedbacks on climate, the development of thaw lakes due to the melt-out of ground ice and subsequent ground subsidence, can have significant impacts on the regional morphology, hydrology, geophysics and biogehemistry. Permafrost degradation as a result of climate warming, which is proceeding considerably faster in high latitude regions than the global average, could lead to either an increases in lake area due to lake expansion, or decrease due to lake drainage. However, which process will dominate is elusive. Therefore understanding thaw lake dynamics and quantifying the feedbacks related to thaw lake expansion and contraction are urgent questions to solve. We apply a stochastic model, THAWLAKE, on four representative Arctic sites, to reproduce recent lake dynamics (1963–2012 and predict for the future changes under various anticipated climate scenarios. The model simulations of current thaw lake cycles and expansion rates are comparable with data. Future lake expansions are limited by lake drainage. We suggest further improvements in the area of enhancing the hydrology component, and operation on larger scales to gauge the impacts on lacustrine morphology and greenhouse gas emissions.

  1. Extreme drought causes distinct water acidification and eutrophication in the Lower Lakes (Lakes Alexandrina and Albert), Australia

    Li, Siyue; Bush, Richard T.; Mao, Rong; Xiong, Lihua; Ye, Chen


    Droughts are set to increase in frequency and magnitude with climate change and water extraction, and understanding their influence on ecosystems is urgent in the Holocene. Low rainfall across the Murray-Darling Basin (MDB) of Australia resulted in an unprecedented water level decline in the Lower Lakes (Lakes Alexandrina and Albert) at the downstream end of the river system. A comprehensive data covering pre-drought (2004-2006), drought (2007-2010) and post-drought (2010-2013) was firstly used to unravel drought effects on water quality in the contrasting main parts and margins of the two Lakes, particularly following water acidification resulting from acid sulfate soil oxidation. Salinity, nutrients and Chl-a significantly increased during the drought in the Lake main waterbody, while pH remained stable or showed minor shifts. In contrast to the Lake Alexandrina, total dissolved solid (TDS) and electrical conductivity (EC) during the post-drought more than doubled the pre-drought period in the Lake Albert as being a terminal lake system with narrow and shallow entrance. Rewetting of the exposed pyrite-containing sediment resulted in very low pH (below 3) in Lake margins, which positively contributed to salinity increases via SO42- release and limestone dissolution. Very acidic water (pH 2-3) was neutralised naturally by lake refill, but aerial limestone dosing was required for neutralisation of water acidity during the drought period. The Lower Lakes are characterized as hypereutrophic with much higher salinity, nutrient and algae concentrations than guideline levels for aquatic ecosystem. These results suggest that, in the Lower Lakes, drought could cause water quality deterioration through water acidification and increased nutrient and Chl-a concentrations, more effective water management in the lake catchment is thus crucial to prevent the similar water quality deterioration since the projected intensification of droughts. A comparative assessment on lake


    G. I. Leychenkov


    Full Text Available In early February 2012, the drill hole at the Vostok Station encountered theLakeVostokwater. This step is important to study the lake composition including possible microbial life and to model subglacial environments however, the next ambitious target of the Vostok Drilling Project is sampling of bottom sediments, which contain the unique record of ice sheet evolution and environmental changes in centralAntarcticafor millions of years. In this connection, the forecast of sedimentary succession based on existing geophysical data, study of mineral inclusions in the accretion ice cores and tectonic models is important task. Interpretation of Airborne geophysical data suggests thatLakeVostokis the part of spacious rift system, which exists at least from Cretaceous. Reflection and refraction seismic experiments conducted in the southern part ofLakeVostokshow very thin (200–300 m stratified sedimentary cover overlying crystalline basement with velocity of 6.0–6.2 km/s. At present, deposition in southernLakeVostokis absent and similar conditions occurred likely at least last3 m.y. when ice sheet aboveLakeVostokchanged insignificantly. It can be also inferred that from the Late Miocene the rate of deposition inLakeVostokwas extremely low and so the most of sedimentary section is older being possibly of Oligocene to early to middle Miocene age when ice sheet oscillated and deposition was more vigorous. If so, the sampling of upper few meters of this condensed section is very informative in terms of history of Antarctic glaciation. Small thickness of sedimentary cover raises a question about existence of lake (rift depression during preglacial and early glacial times.

  3. Deepening Sleep by Hypnotic Suggestion

    Cordi, Maren J.; Schlarb, Angelika A.; Rasch, Björn


    Study Objectives: Slow wave sleep (SWS) plays a critical role in body restoration and promotes brain plasticity; however, it markedly declines across the lifespan. Despite its importance, effective tools to increase SWS are rare. Here we tested whether a hypnotic suggestion to “sleep deeper” extends the amount of SWS. Design: Within-subject, placebo-controlled crossover design. Setting: Sleep laboratory at the University of Zurich, Switzerland. Participants: Seventy healthy females 23.27 ± 3.17 y. Intervention: Participants listened to an auditory text with hypnotic suggestions or a control tape before napping for 90 min while high-density electroencephalography was recorded. Measurements and Results: After participants listened to the hypnotic suggestion to “sleep deeper” subsequent SWS was increased by 81% and time spent awake was reduced by 67% (with the amount of SWS or wake in the control condition set to 100%). Other sleep stages remained unaffected. Additionally, slow wave activity was significantly enhanced after hypnotic suggestions. During the hypnotic tape, parietal theta power increases predicted the hypnosis-induced extension of SWS. Additional experiments confirmed that the beneficial effect of hypnotic suggestions on SWS was specific to the hypnotic suggestion and did not occur in low suggestible participants. Conclusions: Our results demonstrate the effectiveness of hypnotic suggestions to specifically increase the amount and duration of slow wave sleep (SWS) in a midday nap using objective measures of sleep in young, healthy, suggestible females. Hypnotic suggestions might be a successful tool with a lower risk of adverse side effects than pharmacological treatments to extend SWS also in clinical and elderly populations. Citation: Cordi MJ, Schlarb AA, Rasch B. Deepening sleep by hypnotic suggestion. SLEEP 2014;37(6):1143-1152. PMID:24882909

  4. Climate-related differences in the dominance of submerged macrophytes in shallow lakes

    Kosten, S.; Kamarainen, A.; Jeppesen, E.; Nes, van E.H.; Peeters, E.T.H.M.; Lacerot, G.; Scheffer, M.


    It has been suggested that shallow lakes in warm climates have a higher probability of being turbid, rather than macrophyte dominated, compared with lakes in cooler climates, but little field evidence exists to evaluate this hypothesis. We analyzed data from 782 lake years in different climate zones

  5. Interaction of potassium mono and di phosphates with bovine serum albumin studied by fluorescence quenching method.

    Bakkialakshmi, S; Shanthi, B; Chandrakala, D


    The interactions between potassium mono and di phosphates and bovine serum albumin (BSA) were studied using fluorescence spectroscopy (FS) and ultraviolet spectroscopy (UV). The experimental results showed that the potassium mono and di phosphates could insert into the BSA and quench the inner fluorescence of BSA by forming the potassium mono phosphate-BSA and pottassium di phosphate-BSA complexes. It was found that the static quenching was the main reason leading to the fluorescence quenching. It was conformed by XRD and SEM techniques.

  6. Professional iPhone Programming with MonoTouch and .NET/C#

    McClure, Wallace B; Dunn, Craig


    What .NET C# developers need to enter the hot field of iPhone apps. iPhone applications offer a hot opportunity for developers. Until the open source MonoTouch project, this field was limited to those familiar with Apple's programming languages. Now .NET and C# developers can join the party. This Wrox guide is the first book to cover MonoTouch, preparing developers to take advantage of this lucrative opportunity.: MonoTouch opens the field of iPhone app development to .NET and C# developers for the first time; the Wrox reputation among .NET developers assures them that this guide covers everyt

  7. A new approach to modelling and designing mono-block dental implants

    R. Hunter; F. Alister; Möller, J.; J. Alister


    Purpose: of this paper is present a new approach to modelling and design the low cost mono-block dental implants based on the integration of the computer aided techniques. This approach provides the automation of the design process of the mono-block dental implants.Design/methodology/approach: The approach used to develop the modelling and design of the mono-block dental implants are based on the parametrization of the main geometric features of the implants. This approach allows to generate ...

  8. Develop mono-block tooth implants using automate design and FEM analysis

    J.P. Alister; J. Moller,; F. Alister; R. Hunter


    Purpose: Purpose of this paper is present a new approach to modelling and design the low cost mono-block dental implants based on the integration of the computer aided techniques. This approach provides the automation of the design process of the mono-block dental implants.Design/methodology/approach: The approach used to develop the modelling and design of the mono-block dental implants are based on the parametrization of the main geometric features of the implants. This approach allows to ...

  9. Great Lakes Teacher's Guide.

    Reid, Ron

    The Great Lakes are one of the world's greatest reservoirs of fresh water, the foundation of Ontario's economic development, a primary force in ecological systems, and a base for pleasure and recreation. They are also a magnificent resource for the teachers of Ontario. Study of the Great Lakes can bring to life the factors that shape the ecology…

  10. Marine lakes of Indonesia

    Becking, Leontine Elisabeth


    The objective of this thesis was to obtain insight into the processes that play a role in biodiversity patterns of tropical marine species by using marine lakes as a model. Marine lakes are landlocked water bodies that maintain a marine character through narrow submarine connections to the sea. Two

  11. The Great Lakes.

    Seasons, 1987


    The Great Lakes are one of the world's greatest reserviors of fresh water, the foundation of Ontario's economic development, a primary force in ecological systems, and a base for pleasure and recreation. These lakes and their relationship with people of Canada and the United States can be useful as a subject for teaching the impact of human…

  12. Marine lakes of Indonesia

    Becking, Leontine Elisabeth


    The objective of this thesis was to obtain insight into the processes that play a role in biodiversity patterns of tropical marine species by using marine lakes as a model. Marine lakes are landlocked water bodies that maintain a marine character through narrow submarine connections to the sea. Two

  13. New insight into the spawning behavior of lake trout, Salvelinus namaycush, from a recovering population in the Laurentian Great Lakes

    Binder, Thomas R.; Thompson, Henry T.; Muir, Andrew M.; Riley, Stephen C.; Marsden, J. Ellen; Bronte, Charles R.; Krueger, Charles C.


    Spawning behavior of lake trout, Salvelinus namaycush, is poorly understood, relative to stream-dwelling salmonines. Underwater video records of spawning in a recovering population from the Drummond Island Refuge (Lake Huron) represent the first reported direct observations of lake trout spawning in the Laurentian Great Lakes. These observations provide new insight into lake trout spawning behavior and expand the current conceptual model. Lake trout spawning consisted of at least four distinct behaviors: hovering, traveling, sinking, and gamete release. Hovering is a new courtship behavior that has not been previously described. The apparent concentration of hovering near the margin of the spawning grounds suggests that courtship and mate selection might be isolated from the spawning act (i.e., traveling, sinking, and gamete release). Moreover, we interpret jockeying for position displayed by males during traveling as a unique form of male-male competition that likely evolved in concert with the switch from redd-building to itinerant spawning in lake trout. Unlike previous models, which suggested that intra-sexual competition and mate selection do not occur in lake trout, our model includes both and is therefore consistent with evolutionary theory, given that the sex ratio on spawning grounds is skewed heavily towards males. The model presented in this paper is intended as a working hypothesis, and further revision may become necessary as we gain a more complete understanding of lake trout spawning behavior.

  14. A Mono Master Shrug Matching Algorithm for Examination Surveillance

    Sandhya Devi G


    Full Text Available This paper proposes an unusual slant for Shrug recognition from Gesticulation Penetrated Images (GPI based on template matching. Shrugs can be characterized with image templates which are used to compare and match shrugs. The proposed technique makes use of a single template to identify match in the candidates and hence entitled as mono master shrug matching. It does not necessitate erstwhile acquaintance of movements, motion estimation or tracking. The proposed technique brands a unique slant to isolate various shrugs from a given video. Additionally, this method is based on the reckoning of feature invariance to photometric and geometric variations from a given video for the rendering of the shrugs in a lexicon. This descriptor extraction method includes the standard deviation of the gesticulation penetrated images of a shrug. The comparison is based on individual and rational actions with exact definitions varying widely uses histogram based tracker which computes the deviation of the candidate shrugs from the template shrug. Far-reaching investigation is done on a very intricate and diversified dataset to establish the efficacy of retaining the anticipated method.

  15. Adding Mono- and Multivalent Ions to Lyotropic Chromonic Liquid Crystals

    Tortora, Luana; Park, Heung-Shik; Antion, Kelly; Woolwerton, Chris; Finotello, Daniele; Lavrentovich, Oleg


    Lyotropic Chromonic Liquid Crystals (LCLCs) are a distinct class of liquid crystals formed in aqueous solutions by molecules with rigid polyaromatic cores and ionic groups at the periphery [1-4]. The phase diagrams of these materials should depend on entropic factors (as in the Onsager model) and electrostatic interactions. Using optical polarizing microscopy, we studied the effects of mono- and multivalent ions on the phase diagrams of Blue 27 [3] and Sunset Yellow [2]. The monovalent ions change the temperatures of phase transitions, as described in [4], while the effect of multivalent ions is more dramatic and, in addition to the changed temperatures of phase transitions by tens of degrees, it often involves condensation of LCLC aggregates into domains with birefringence much higher than that in a normal nematic phase. Work supported by OBR B-7844. [1]J. Lydon, Current Opin. Colloid & Interface Sci. 3, 458 (1998);8, 480-489 (2004); [2]V. R. Horowitz, L. A. Janowitz, A. L. Modic, P. J. Heiney, and P. J. Collings, 2005, Phys. Rew. E 72, 041710; [3]Yu. A. Nastishin, H. Liu, T. Schneider, T., V. Nazarenko, R. Vasyuta, S. V. Shiyanovskii, and O. D. Lavrentovich, 2005, Phys. Rev. E 72, 041711; [4]A.F. Kostko, B. H. Cipriano, O. A. Pinchuk, L. Ziserman, M. A. Anisimov, D. Danino, and S. R. Raghavan. J. Phys. Chem. B 109, 19126-19133 (2005)

  16. Similar Sister Chromatid Arrangement in Mono- and Holocentric Plant Chromosomes.

    Schubert, Veit; Zelkowski, Mateusz; Klemme, Sonja; Houben, Andreas


    Due to the X-shape formation at somatic metaphase, the arrangement of the sister chromatids is obvious in monocentric chromosomes. In contrast, the sister chromatids of holocentric chromosomes cannot be distinguished even at mitotic metaphase. To clarify their organization, we differentially labelled the sister chromatids of holocentric Luzula and monocentric rye chromosomes by incorporating the base analogue EdU during replication. Using super-resolution structured illumination microscopy (SIM) and 3D rendering, we found that holocentric sister chromatids attach to each other at their contact surfaces similar to those of monocentrics in prometaphase. We found that sister chromatid exchanges (SCEs) are distributed homogeneously along the whole holocentric chromosomes of Luzula, and that their occurrence is increased compared to monocentric rye chromosomes. The SCE frequency of supernumerary B chromosomes, present additionally to the essential A chromosome complement of rye, does not differ from that of A chromosomes. Based on these results, models of the sister chromatid arrangement in mono- and holocentric plant chromosomes are presented.

  17. Fringing in MonoCam Y4 filter images

    Brooks, J.; Fisher-Levine, M.; Nomerotski, A.


    We study the fringing patterns observed in MonoCam, a camera with a single Large Synoptic Survey Telescope (LSST) CCD sensor. Images were taken at the U.S. Naval Observatory in Flagstaff, Arizona (NOFS) employing its 1.3 m telescope and an LSST y4 filter. Fringing occurs due to the reflection of infrared light (700 nm or larger) from the bottom surface of the CCD which constructively or destructively interferes with the incident light to produce a net ``fringe'' pattern which is superimposed on all images taken. Emission lines from the atmosphere, dominated by hydroxyl (OH) spectra, can change in their relative intensities as the night goes on, producing different fringe patterns in the images taken. We found through several methods that the general shape of the fringe patterns remained constant, though with slight changes in the amplitude and phase of the fringes. We also found that a superposition of fringes from two monochromatic lines taken in the lab offered a reasonable description of the sky data.


    Yu-da Lai


    Full Text Available This paper explores the auditory lexical access of mono-morphemic compounds in Chinese as a way of understanding the role of orthography in the recognition of spoken words. In traditional Chinese linguistics, a compound is a word written with two or more characters whether or not they are morphemic. A monomorphemic compound may either be a binding word, written with characters that only appear in this one word, or a non-binding word, written with characters that are chosen for their pronunciation but that also appear in other words. Our goal was to determine if this purely orthographic difference affects auditory lexical access by conducting a series of four experiments with materials matched by whole-word frequency, syllable frequency, cross-syllable predictability, cohort size, and acoustic duration, but differing in binding. An auditory lexical decision task (LDT found an orthographic effect: binding words were recognized more quickly than non-binding words. However, this effect disappeared in an auditory repetition and in a visual LDT with the same materials, implying that the orthographic effect during auditory lexical access was localized to the decision component and involved the influence of cross-character predictability without the activation of orthographic representations. This claim was further confirmed by overall faster recognition of spoken binding words in a cross-modal LDT with different types of visual interference. The theoretical and practical consequences of these findings are discussed.

  19. Antioxidant and cytotoxic activity of mono- and bissalicylic acid derivatives

    Đurendić Evgenija A.


    Full Text Available A simple synthesis of mono- and bis-salicylic acid derivatives 1-10 by the transesterification of methyl salicylate (methyl 2-hydroxybenzoate with 3-oxapentane-1,5-diol, 3,6- dioxaoctane-1,8-diol, 3,6,9-trioxaundecane-1,11-diol, propane-1,2-diol or 1-aminopropan- 2-ol in alkaline conditions is reported. All compounds were tested in vitro on three malignant cell lines (MCF-7, MDA-MB-231, PC-3 and one non-tumor cell line (MRC- 5. Strong cytotoxicity against prostate PC-3 cancer cells expressed compounds 3, 4, 6, 9 and 10, all with the IC50 less than 10 μmol/L, which were 11-27 times higher than the cytotoxicity of antitumor drug doxorubicin. All tested compounds were not toxic against the non-tumor MRC-5 cell line. Antioxidant activity of the synthesized derivatives was also evaluated. Compounds 2, 5 and 8 were better OH radical scavengers than commercial antioxidants BHT and BHA. The synthesized compounds showed satisfactory scavenger activity, which was studied by QSAR modeling. A good correlation between the experimental variables IC50 DPPH and IC50 OH and MTI (molecular topological indices molecular descriptors and CAA (accessible Connolly solvent surface area for the new compounds 1, 3, and 5 was observed.

  20. Mono-energy coronary angiography with a compact light source

    Eggl, Elena; Mechlem, Korbinian; Braig, Eva; Kulpe, Stephanie; Dierolf, Martin; Günther, Benedikt; Achterhold, Klaus; Herzen, Julia; Gleich, Bernhard; Rummeny, Ernst; Noël, Peter B.; Pfeiffer, Franz; Muenzel, Daniela


    While conventional x-ray tube sources reliably provide high-power x-ray beams for everyday clinical practice, the broad spectra that are inherent to these sources compromise the diagnostic image quality. For a monochromatic x-ray source on the other hand, the x-ray energy can be adjusted to optimal conditions with respect to contrast and dose. However, large-scale synchrotron sources impose high spatial and financial demands, making them unsuitable for clinical practice. During the last decades, research has brought up compact synchrotron sources based on inverse Compton scattering, which deliver a highly brilliant, quasi-monochromatic, tunable x-ray beam, yet fitting into a standard laboratory. One application that could benefit from the invention of these sources in clinical practice is coronary angiography. Being an important and frequently applied diagnostic tool, a high number of complications in angiography, such as renal failure, allergic reaction, or hyperthyroidism, are caused by the large amount of iodine-based contrast agent that is required for achieving sufficient image contrast. Here we demonstrate monochromatic angiography of a porcine heart acquired at the MuCLS, the first compact synchrotron source. By means of a simulation, the CNR in a coronary angiography image achieved with the quasi-mono-energetic MuCLS spectrum is analyzed and compared to a conventional x-ray-tube spectrum. The results imply that the improved CNR achieved with a quasi-monochromatic spectrum can allow for a significant reduction of iodine contrast material.

  1. Winter anoxic layer in Lake Hibara

    Sato, Yasuhiro; KUMAGAI, Michio; Sugawara, Kotaro; Miyamori, Yasushi


    Abstract : The concentration of dissolved oxygen in waters 0.5-0.6m above the bottom of Lake Hibara, a dimictic lake, was zero in early spring of 1994 and 1997. The concentrations in early spring of 1992, 1993, 1995, 1996, and 1998 ranged from 3.75 to 10.1mg1~-1. The depth profiles of water temperature suggest that water had not circulated prior to the sample collections of 1994 and 1997, but it had done so in the cases of the other years, suggesting that winter conditions were well preserved...

  2. Lake bed classification using acoustic data

    Yin, Karen K.; Li, Xing; Bonde, John; Richards, Carl; Cholwek, Gary


    As part of our effort to identify the lake bed surficial substrates using remote sensing data, this work designs pattern classifiers by multivariate statistical methods. Probability distribution of the preprocessed acoustic signal is analyzed first. A confidence region approach is then adopted to improve the design of the existing classifier. A technique for further isolation is proposed which minimizes the expected loss from misclassification. The devices constructed are applicable for real-time lake bed categorization. A mimimax approach is suggested to treat more general cases where the a priori probability distribution of the substrate types is unknown. Comparison of the suggested methods with the traditional likelihood ratio tests is discussed.

  3. Movement patterns and spatial segregation of two populations of lake trout Salvelinus namaycush in Lake Huron

    Binder, Thomas; Marsden, J. Ellen; Riley, Stephen; Johnson, James E.; Johnson, Nicholas; He, Ji; Ebener, Mark P.; Holbrook, Christopher; Bergstedt, Roger A.; Bronte, Charles R.; Hayden, Todd A.; Krueger, Charles C.


    Movement ecology is an important component of life history and population dynamics, and consequently its understanding can inform successful fishery management decision-making. While lake trout populations in Lake Huron have shown signs of recovery from near extinction in recent years, knowledge of their movement behavior remains incomplete. We used acoustic telemetry to describe and compare movement patterns of two Lake Huron lake trout populations: Drummond Island and Thunder Bay. Both populations showed high spawning site fidelity, with no evidence of co-mingling during non-spawning season. Detections between spawning periods were mainly limited to receivers within 100 km of spawning locations, and suggested that the two populations likely remained segregated throughout the year. Drummond Island fish, which spawn inside the Drummond Island Refuge, primarily dispersed east into Canadian waters of Lake Huron, with 79–92% of fish being detected annually on receivers outside the refuge. In contrast, Thunder Bay fish tended to disperse south towards Saginaw Bay. Large proportions (i.e., > 80%) of both populations were available to fisheries outside the management zone containing their spawning location. Thunder Bay fish moved relatively quickly to overwinter habitat after spawning, and tended to repeat the same post-spawning movement behavior each year. The consistent, predictable movement of both populations across management zones highlights the importance of understanding population dynamics to effective management of Lake Huron lake trout.

  4. Seismic reflection data from Lake Elsinore, Southern CA, reveal a sustained late-Holocene lake lowstand

    Pyke, B. N.; Kirby, M. E.; Scholz, C. A.; Cattaneo, P.


    Lake Elsinore, located 120 kilometers southeast of Los Angeles, California, is Southern California’s largest natural lake. In December 2008, we collected over 75 km of high-resolution seismic reflection data using a CHIRP single-channel seismic-reflection Edgetech Geostar and the Geopulse™ Boomer systems. Initial interpretations reveal several interesting seismic sequences over the past 10,000 calendar years before present (cy BP: age control is based on dated sediment cores tied to the seismic lines). Most intriguing is evidence for a sustained interval of low lake level bracketed between ~ 3,000 and 1,800 cy BP. Prominent truncated stratal terminations characterize the upper boundary of this low stand seismic sequence. Sediment core data in the form of mudcracks, grain size variations, and geochemical data from various depositional environments (i.e., littoral and profundal) within Lake Elsinore support the seismic reflection interpretation for a low stand. Regionally, there is evidence for a similar interval of dry climate at Tulare Lake, the Mojave lakes, the Salton Sea, and possibly Dry Lake. A comparison to marine proxies along the eastern Pacific is less straight forward. The reason for this interval of sustained dry climate is not clear at this time. However, these results suggest that the already water-poor, over populated region of Southern California is subject to “droughts” of longer duration than that seen in the historical or tree-ring records from the region.

  5. Trophic relationships between a native and a nonnative predator in a system of natural lakes

    Meeuwig, Michael H.; Guy, Christopher S.; Fedenberg, Wade A.


    Bull trout, a species of char listed as threatened under the US Endangered Species Act, have been displaced from portions of their historic range following the introduction of nonnative lake trout. It has been suggested that competitive exclusion as a result of trophic overlap between bull trout and lake trout may be the causal mechanism associated with displacement of bull trout. This study used stable isotope data to evaluate trophic relationships among native bull trout, nonnative lake trout and other fishes in seven lakes in Glacier National Park (GNP), Montana. Bull trout and lake trout had greater δ15N values relative to other fishes among lakes (δ15N = 3.0‰). Lake trout had greater δ15N values relative to bull trout (δ15N = +1.0‰). Bull trout had greater δ13C values relative to lake trout in six of the seven lakes examined. Although both bull trout and lake trout had greater δ15N values relative to other fishes within lakes in GNP, differences in δ15N and 13C between bull trout and lake trout suggest that they are consuming different prey species or similar prey species in different proportions. Therefore, displacement of bull trout as a direct result of complete overlap in food resource use is not anticipated unless diet shifts occur or food resources become limiting. Additionally, future studies should evaluate food habits to identify important prey species and sources of partial dietary overlap between bull trout and lake trout.

  6. Characterizing supraglacial lake drainage and freezing on the Greenland Ice Sheet

    N. Selmes


    Full Text Available The behaviour of supraglacial lakes on the Greenland Ice Sheet has attracted a great deal of focus, specifically with regard to their fast drainage through hydrofracturing to the ice sheet base. However, a previous study has shown that this mode of drainage accounts for only 13% of the lakes on the Greenland Ice Sheet. No published work to date has studied what happens to those lakes that do not drain suddenly. We present here three possible modes by which lakes can disappear from the ice sheet, which will have strongly contrasting effects on glacial dynamics and the ice sheet water budget. Around half of all supraglacial lakes observed persisted through the melt season and froze at the end of summer. A third drained slowly, which we interpret to be a result of incision of the supraglacial lake exit-channel. The fate of 7% of lakes could not be observed due to cloud cover, and the remainder drained suddenly. Both fast and slow lake drainage types are absent at higher elevations where lakes tend to freeze despite having similar or longer life spans to lakes at lower elevations, suggesting the mechanisms of drainage are inhibited. Groups of neighbouring lakes were observed to drain suddenly on the same day suggesting a common trigger mechanism for drainage initiation. We find that great care must be taken when interpreting remotely sensed observations of lake drainage, as fast and slow lake drainage can easily be confused if the temporal resolution used is too coarse.

  7. Lake trout in northern Lake Huron spawn on submerged drumlins

    Riley, Stephen C.; Binder, Thomas; Wattrus, Nigel J.; Faust, Matthew D.; Janssen, John; Menzies, John; Marsden, J. Ellen; Ebener, Mark P.; Bronte, Charles R.; He, Ji X.; Tucker, Taaja R.; Hansen, Michael J.; Thompson, Henry T.; Muir, Andrew M.; Krueger, Charles C.


    Recent observations of spawning lake trout Salvelinus namaycush near Drummond Island in northern Lake Huron indicate that lake trout use drumlins, landforms created in subglacial environments by the action of ice sheets, as a primary spawning habitat. From these observations, we generated a hypothesis that may in part explain locations chosen by lake trout for spawning. Most salmonines spawn in streams where they rely on streamflows to sort and clean sediments to create good spawning habitat. Flows sufficient to sort larger sediment sizes are generally lacking in lakes, but some glacial bedforms contain large pockets of sorted sediments that can provide the interstitial spaces necessary for lake trout egg incubation, particularly if these bedforms are situated such that lake currents can penetrate these sediments. We hypothesize that sediment inclusions from glacial scavenging and sediment sorting that occurred during the creation of bedforms such as drumlins, end moraines, and eskers create suitable conditions for lake trout egg incubation, particularly where these bedforms interact with lake currents to remove fine sediments. Further, these bedforms may provide high-quality lake trout spawning habitat at many locations in the Great Lakes and may be especially important along the southern edge of the range of the species. A better understanding of the role of glacially-derived bedforms in the creation of lake trout spawning habitat may help develop powerful predictors of lake trout spawning locations, provide insight into the evolution of unique spawning behaviors by lake trout, and aid in lake trout restoration in the Great Lakes.

  8. Historical trophic evolutions and their ecological responses from shallow lakes in the middle and lower reaches of the Yangtze River: Case studies on Longgan Lake and Taibai Lake


    The evolutions of diatom floras and the total phosphorous (TP) concentrations in the historical period were reconstructed for two lakes, Longgan and Taibai in the middle Yangtze River,based on high resolutional fossil diatom study from two sediment cores and an established regional diatom-TP transfer function. The TP concentration in Longgan Lake changed slightly in the range of 36-62 μg/L and kept its middle trophic level in the past 200 years. The changes of diatom assemblages reflect a macrophyte-dominated history of the lake. During the nineteenth century, the lake TP concentration increased comparatively, corresponding to the increase in abundance of benthic diatoms. The progressive increase of epiphytic diatoms since the onset of the twentieth century indicates the development of aquatic plants, coinciding with the twice drops of water TP level. The TP concentration in Taibai Lake kept a stable status about 50 μg/L before 1953 AD, while diatoms dominated by facultative planktonic Aulacoseira granulata shifted quickly to epiphytic diatom species, indicating a rapid expansion of aquatic vegetation. During 1953-1970 AD, the coverage of aquatic plants decreased greatly inferred by the low abundance of epiphytic diatoms as well as declined planktonic types, and the reconstructed TP concentration shows an obvious rising trend firstly, suggesting the beginning of the lake eutrophication. The lake was in the eutrophic condition after 1970, coinciding with the successive increase of planktonic diatoms. The comparison of the two lakes suggests the internal adjustment and purification function of aquatic plants for nutrients in water. The discrepancy of TP trends in the two lakes after 1960 reflects two different patterns of lake environmental response to human disturbance. Sediments in Taibai Lake clearly recorded the process of lake ecological transformation from the macrophyte-dominated stage to the algae-dominated stage. The limits of TP concentration (68-118

  9. Lake metabolism scales with lake morphometry and catchment conditions

    Stæhr, Peter A.; Baastrup-Spohr, Lars; Jensen, Kaj Sand;


    We used a comparative data set for 25 lakes in Denmark sampled during summer to explore the influence of lake morphometry, catchment conditions, light availability and nutrient input on lake metabolism. We found that (1) gross primary production (GPP) and community respiration (R) decline with lake...... area, water depth and drainage ratio, and increase with algal biomass (Chl), dissolved organic carbon (DOC) and total phosphorus (TP); (2) all lakes, especially small with less incident light, and forest lakes with high DOC, have negative net ecosystem production (NEP ... decreases with lake area and water depth as a consequence of lower input of nutrients and organic matter per unit water volume; (4) the influence of benthic processes on free water metabolic measures declines with increasing lake size; and (5) with increasing lake size, lake metabolism decreases...

  10. Predicting the locations of naturally fishless lakes

    Schilling, Emily Gaenzle; Loftin, C.S.; Degoosh, K.E.; Huryn, Alexander D.; Webster, K.E.


    complementary approaches. First we visited 21 lakes predicted to be fishless and assessed current fish presence with gillnetting. Second, we used paleolimnological techniques based on the abundance of Chaoborus americanus mandibles in the bottom segments of sediment cores. Fifteen of the 21 lakes predicted to be fishless currently contain fish. Paleolimnological evidence, however, suggests that nine of the 15 lakes were historically fishless and thus were subject to undocumented fish introductions. 8. Our approach efficiently predicts the distribution Maine's naturally fishless lakes, and our results indicate that these habitats have declined due to fish introductions. Our method could be applied to other regions with similar geographic and geomorphic constraints on fish distributions as a tool to enhance conservation of a limited resource that provides habitat for unique biological communities. ?? 2007 Blackwell Publishing Ltd.

  11. Depth, ice thickness, and ice-out timing cause divergent hydrologic responses among Arctic lakes

    Arp, Christopher D.; Jones, Benjamin M.; Liljedahl, Anna K.; Hinkel, Kenneth M.; Welker, Jeffery A.


    Lakes are prevalent in the Arctic and thus play a key role in regional hydrology. Since many Arctic lakes are shallow and ice grows thick (historically 2-m or greater), seasonal ice commonly freezes to the lake bed (bedfast ice) by winter's end. Bedfast ice fundamentally alters lake energy balance and melt-out processes compared to deeper lakes that exceed the maximum ice thickness (floating ice) and maintain perennial liquid water below floating ice. Our analysis of lakes in northern Alaska indicated that ice-out of bedfast ice lakes occurred on average 17 days earlier (22-June) than ice-out on adjacent floating ice lakes (9-July). Earlier ice-free conditions in bedfast ice lakes caused higher open-water evaporation, 28% on average, relative to floating ice lakes and this divergence increased in lakes closer to the coast and in cooler summers. Water isotopes (18O and 2H) indicated similar differences in evaporation between these lake types. Our analysis suggests that ice regimes created by the combination of lake depth relative to ice thickness and associated ice-out timing currently cause a strong hydrologic divergence among Arctic lakes. Thus understanding the distribution and dynamics of lakes by ice regime is essential for predicting regional hydrology. An observed regime shift in lakes to floating ice conditions due to thinner ice growth may initially offset lake drying because of lower evaporative loss from this lake type. This potential negative feedback caused by winter processes occurs in spite of an overall projected increase in evapotranspiration as the Arctic climate warms.

  12. Antinociceptive and Anti-Inflammatory Effects of Zerumbone against Mono-Iodoacetate-Induced Arthritis.

    Chien, Ting-Yi; Huang, Steven Kuan-Hua; Lee, Chia-Jung; Tsai, Po-Wei; Wang, Ching-Chiung


    The fresh rhizome of Zingiber zerumbet Smith (Zingiberaceae) is used as a food flavoring and also serves as a folk medicine as an antipyretic and for analgesics in Taiwan. Zerumbone, a monocyclic sesquiterpene was isolated from the rhizome of Z. zerumbet and is the major active compound. In this study, the anti-inflammatory and antinociceptive effects of zerumbone on arthritis were explored using in vitro and in vivo models. Results showed that zerumbone inhibited inducible nitric oxide (NO) synthase (iNOS), cyclooxygenase (COX)-2 expressions, and NO and prostaglandin E₂ (PGE₂) production, but induced heme oxygenase (HO)-1 expression in a dose-dependent manner in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. When zerumbone was co-treated with an HO-1 inhibitor (tin protoporphyrin (SnPP)), the NO inhibitory effects of zerumbone were recovered. The above results suggest that zerumbone inhibited iNOS and COX-2 through induction of the HO-1 pathway. Moreover, matrix metalloproteinase (MMP)-13 and COX-2 expressions of interleukin (IL)-1β-stimulated primary rat chondrocytes were inhibited by zerumbone. In an in vivo assay, an acetic acid-induced writhing response in mice was significantly reduced by treatment with zerumbone. Furthermore, zerumbone reduced paw edema and the pain response in a mono-iodoacetate (MIA)-induced rat osteoarthritis model. Therefore, we suggest that zerumbone possesses anti-inflammatory and antinociceptive effects which indicate zerumbone could be a potential candidate for osteoarthritis treatment.

  13. Antinociceptive and Anti-Inflammatory Effects of Zerumbone against Mono-Iodoacetate-Induced Arthritis

    Ting-Yi Chien


    Full Text Available The fresh rhizome of Zingiber zerumbet Smith (Zingiberaceae is used as a food flavoring and also serves as a folk medicine as an antipyretic and for analgesics in Taiwan. Zerumbone, a monocyclic sesquiterpene was isolated from the rhizome of Z. zerumbet and is the major active compound. In this study, the anti-inflammatory and antinociceptive effects of zerumbone on arthritis were explored using in vitro and in vivo models. Results showed that zerumbone inhibited inducible nitric oxide (NO synthase (iNOS, cyclooxygenase (COX-2 expressions, and NO and prostaglandin E2 (PGE2 production, but induced heme oxygenase (HO-1 expression in a dose-dependent manner in lipopolysaccharide (LPS-stimulated RAW 264.7 cells. When zerumbone was co-treated with an HO-1 inhibitor (tin protoporphyrin (SnPP, the NO inhibitory effects of zerumbone were recovered. The above results suggest that zerumbone inhibited iNOS and COX-2 through induction of the HO-1 pathway. Moreover, matrix metalloproteinase (MMP-13 and COX-2 expressions of interleukin (IL-1β-stimulated primary rat chondrocytes were inhibited by zerumbone. In an in vivo assay, an acetic acid-induced writhing response in mice was significantly reduced by treatment with zerumbone. Furthermore, zerumbone reduced paw edema and the pain response in a mono-iodoacetate (MIA-induced rat osteoarthritis model. Therefore, we suggest that zerumbone possesses anti-inflammatory and antinociceptive effects which indicate zerumbone could be a potential candidate for osteoarthritis treatment.

  14. 长江中下游地区湖泊资源可持续利用%The Sustainable Utilization of Lake Resources in the Middle and Lower Reaches of Yangtze River


    Based on geographical and hydrological characteristics of lakes in the middle and lower reaches of Yangtze River, this paper analyzes the factors rest ricting the sustainable utilization of lake resources, including the conflict am ong agriculture water conservancy, and fishery, lake water pollution and eutroph ication, lake siltation and swamping. The countermeasures and suggestions, such a s improving the strategic status of lake harnessing, strengthening integrated ma nagement of lakes and their watershed, strengthening researches on lake environm ent and lake resources, are proposed to practice the sustainable utilization of lake resources.

  15. Mono-Cycle Photonics and Optical Scanning Tunneling Microscopy Route to Femtosecond Ångstrom Technology

    Yamashita, Mikio; Morita, Ryuji


    "Mono-Cycle Photonics and Optical Scanning Tunneling Microscopy" deals with both the ultrashort laser-pulse technology in the few- to mono-cycle region and the laser-surface-controlled scanning-tunneling microscopy (STM) extending into the spatiotemporal extreme technology. The former covers the theory of nonlinear pulse propagation beyond the slowly-varing-envelope approximation, the generation and active chirp compensation of ultrabroadband optical pulses, the amplitude and phase characterization of few- to mono-cycle pulses, and the feedback field control for the mono-cycle-like pulse generation. In addition, the wavelength-multiplex shaping of ultrabroadband pulse is described. The latter covers the CW-laser-excitation STM, the femtosecond-time-resolved STM and atomic-level surface phenomena controlled by femtosecond pulses.

  16. Developing C# Apps for iPhone and iPad using MonoTouch

    Costanich, Bryan


    Developing C# Applications for iPhone and iPad using MonoTouch shows you how to use your existing C# skills to write apps for the iPhone and iPad. Fortunately, there's MonoTouch, Novell's .NET library that allows C# developers to write C# code that executes in iOS. Furthermore, MonoTouch allows you to address all the unique functions of the iPhone, iPod Touch, and iPad. And the big plus: You needn't learn any Objective-C to master MonoTouch!. Former Microsoft engineer and published app-store developer Bryan Costanich shows you how to use the tools you already know to create native apps in iOS

  17. Repairing split ends: SIRT6, mono-ADP ribosylation and DNA repair

    Van Meter, Michael; Mao, Zhiyong; Gorbunova, Vera; Seluanov, Andrei


    The sirtuin gene family comprises an evolutionarily ancient set of NAD+ dependent protein deacetylase and mono-ADP ribosyltransferase enzymes. Found in all domains of life, sirtuins regulate a diverse array of biological processes, including DNA repair, gene silencing, apoptosis and metabolism. Studies in multiple model organisms have indicated that sirtuins may also function to extend lifespan and attenuate age-related pathologies. To date, most of these studies have focused on the deacetylase activity of sirtuins, and relatively little is known about the other biochemical activity of sirtuins, mono-ADP ribosylation. We recently reported that the mammalian sirtuin, SIRT6, mono-ADP ribosylates PARP1 to promote DNA repair in response to oxidative stress. In this research perspective we review the role of SIRT6 in DNA repair and discuss the emerging implications for sirtuin directed mono-ADP ribosylation in aging and age-related diseases. PMID:21946623

  18. Lake Nasser evaporation reduction study

    Hala M.I. Ebaid


    Full Text Available This study aims to evaluate the reduction of evaporation of Lake Nasser’s water caused by disconnecting (fully or partially some of its secondary channels (khors. This evaluation integrates remote sensing, Geographic Information System (GIS techniques, aerodynamic principles, and Landsat7 ETM+ images. Three main procedures were carried out in this study; the first derived the surface temperature from Landsat thermal band; the second derived evaporation depth and approximate evaporation volume for the entire lake, and quantified evaporation loss to the secondary channels’ level over one month (March by applied aerodynamic principles on surface temperature of the raster data; the third procedure applied GIS suitability analysis to determine which of these secondary channels (khors should be disconnected. The results showed evaporation depth ranging from 2.73 mm/day at the middle of the lake to 9.58 mm/day at the edge. The evaporated water-loss value throughout the entire lake was about 0.86 billion m3/month (March. The analysis suggests that it is possible to save an approximate total evaporation volume loss of 19.7 million m3/month (March, and thus 2.4 billion m3/year, by disconnecting two khors with approximate construction heights of 8 m and 15 m. In conclusion, remote sensing and GIS are useful for applications in remote locations where field-based information is not readily available and thus recommended for decision makers remotely planning in water conservation and management.

  19. Unusual bacterioplankton community structure in ultra-oligotrophic Crater Lake

    Urbach, Ena; Vergin, Kevin L.; Morse, Ariel


    The bacterioplankton assemblage in Crater Lake, Oregon (U.S.A.), is different from communities found in other oxygenated lakes, as demonstrated by four small subunit ribosomal ribonucleic acid (SSU rRNA) gene clone libraries and oligonucleotide probe hybridization to RNA from lake water. Populations in the euphotic zone of this deep (589 m), oligotrophic caldera lake are dominated by two phylogenetic clusters of currently uncultivated bacteria: CL120-10, a newly identified cluster in the verrucomicrobiales, and ACK4 actinomycetes, known as a minor constituent of bacterioplankton in other lakes. Deep-water populations at 300 and 500 m are dominated by a different pair of uncultivated taxa: CL500-11, a novel cluster in the green nonsulfur bacteria, and group I marine crenarchaeota. b-Proteobacteria, dominant in most other freshwater environments, are relatively rare in Crater Lake (marine crenarchaeota and green nonsulfur bacteria. Comparison of Crater Lake to other lakes studied by rRNA methods suggests that selective factors structuring Crater Lake bacterioplankton populations may include low concentrations of available trace metals and dissolved organic matter, chemistry of infiltrating hydrothermal waters, and irradiation by high levels of ultraviolet light.

  20. Rapid Loss of Lakes on the Mongolian Plateau

    Tao, S.; Fang, J.; Zhao, X.; Zhao, S.; Shen, H.; Hu, H.; Tang, Z.; Wang, Z.; Guo, Q.


    Lakes are widely distributed on the Mongolian Plateau and as critical water sources have sustained Mongolian pastures for hundreds of years. However, the plateau has experienced significant lake shrinkage and grassland degradation during the past several decades. To quantify the changes in all the lakes on the plateau and the associated driving factors, we performed a satellite-based survey using multi-temporal Landsat images from the 1970s to 2000s, combining with ground-based censuses. Our results document a rapid loss of lakes on the plateau in the past decades: the number of lakes with a water surface area >1 km2 decreased from 785 in the late 1980s to 577 in 2010, with a greater rate of decrease (34.0%) in Inner Mongolia of China than in Mongolia (17.6%). This decrease has been particularly pronounced since the late 1990s in Inner Mongolia and the number of lakes >10 km2 has declined by 30.0%. The statistical analyses suggested that in Mongolia precipitation was the dominant driver for the lake changes, while in Inner Mongolia coal mining was most important in its grassland area and irrigation was the leading factor in its cultivated area. The deterioration of lakes is expected to continue in the following decades not only because of changing climate but also increasing exploitation of underground mineral and groundwater resources on the plateau. To protect grasslands and the indigenous nomads, effective action is urgently required to save these valuable lakes from further deterioration.

  1. A Proposed Aquatic Plant Community Biotic Index for Wisconsin Lakes

    Nichols, Stanley; Weber, Steven; Shaw, Byron


    The Aquatic Macrophyte Community Index (AMCI) is a multipurpose tool developed to assess the biological quality of aquatic plant communities in lakes. It can be used to specifically analyze aquatic plant communities or as part of a multimetric system to assess overall lake quality for regulatory, planning, management, educational, or research purposes. The components of the index are maximum depth of plant growth; percentage of the littoral zone vegetated; Simpson's diversity index; the relative frequencies of submersed, sensitive, and exotic species; and taxa number. Each parameter was scaled based on data distributions from a statewide database, and scaled values were totaled for the AMCI value. AMCI values were grouped and tested by ecoregion and lake type (natural lakes and impoundments) to define quality on a regional basis. This analysis suggested that aquatic plant communities are divided into four groups: (1) Northern Lakes and Forests lakes and impoundments, (2) North-Central Hardwood Forests lakes and impoundments, (3) Southeastern Wisconsin Till Plains lakes, and (4) Southeastern Wisconsin Till Plains impoundments, Driftless Area Lakes, and Mississippi River Backwater lakes. AMCI values decline from group 1 to group 4 and reflect general water quality and human use trends in Wisconsin. The upper quartile of AMCI values in any region are the highest quality or benchmark plant communities. The interquartile range consists of normally impacted communities for the region and the lower quartile contains severely impacted or degraded plant communities. When AMCI values were applied to case studies, the values reflected known impacts to the lakes. However, quality criteria cannot be used uncritically, especially in lakes that initially have low nutrient levels.

  2. Mono-X, dijet, and long-lived particle searches at the LHC

    McDonald, Emily; The ATLAS collaboration


    This document presents a summary of the most recent Run II searches and results in the mono-X (photon, Z/W/H), mono-/di-jet, and long-lived particle channels for the ATLAS and CMS experiments. Limits on Simplified Models of dark matter and Effective Field Theories in each channel are also presented where relevant as a complement to the SUSY, BSM Higgs, and Invisible Higgs results which are to be covered in a separate presentation.

  3. Baker's yeast mediated reduction of substituted acenaphthenequinones: Regio- and enantioselective preparation of mono-hydroxyacenaphthenones

    Xing Yong Wang; Jing Nan Cui; Wei Min Ren; Feng Li; Chun Liang Lu; Xu Hong Qian


    Baker's yeast mediated reduction of acenaphthenequinone within 4-10 h afforded mono-hydroxyacenaphthenone mainly with low enantioselectivity, the substrate and mono-hydroxyacenaphthenone product almost converted to dihydroxyacenaphthene after 48 h.By control of the reaction time and in the presence of DMF as co-solvent, the reduction of 6-substituted acenaphthenequinones under vigorous agitation afforded the corresponding 2-hydroxyacenaphthenones in 24-84% yields with 10-93% ee.

  4. Evidence that Mono-ADP-Ribosylation of CtBP1/BARS Regulates Lipid Storage

    Bartz, René; Seemann, Joachim; Zehmer, John K.; Serrero, Ginette; Kent D. Chapman; Anderson, Richard G. W.; Liu, Pingsheng


    Mono-ADP-ribosylation is emerging as an important posttranslational modification that modulates a variety of cell signaling pathways. Here, we present evidence that mono-ADP-ribosylation of the transcriptional corepressor C terminal binding protein, brefeldin A (BFA)-induced ADP-ribosylated substrate (CtBP1/BARS) regulates neutral lipid storage in droplets that are surrounded by a monolayer of phospholipid and associated proteins. CtBP1/BARS is an NAD-binding protein that becomes ribosylated ...

  5. Geothermal systems of the Mono Basin-Long Valley region, eastern California and western Nevada

    Higgins, C.T.; Flynn, T.; Chapman, R.H.; Trexler, D.T.; Chase, G.R.; Bacon, C.F.; Ghusn, G. Jr.


    The region that includes Mono Basin, Long Valley, the Bridgeport-Bodie Hills area, and Aurora, in eastern California and western Nevada was studied to determine the possible causes and interactions of the geothermal anomalies in the Mono Basin-Long Valley region as a whole. A special goal of the study was to locate possible shallow bodies of magma and to determine their influence on the hydrothermal systems in the region. (ACR)

  6. Asynchrony in the inter-annual recruitment of lake whitefish Coregonus clupeaformis in the Great Lakes region

    Zischke, Mitchell K.; Bunnell, David; Troy, Cary D.; Berglund, Eric K.; Caroffino, David C.; Ebener, Mark P.; He, Ji X.; Sitar, Shawn P.; Hook, Tomas O.


    Spatially separated fish populations may display synchrony in annual recruitment if the factors that drive recruitment success, particularly abiotic factors such as temperature, are synchronised across broad spatial scales. We examined inter-annual variation in recruitment among lake whitefish (Coregonus clupeaformis) populations in lakes Huron, Michigan and Superior using fishery-dependent and -independent data from 1971 to 2014. Relative year-class strength (RYCS) was calculated from catch-curve residuals for each year class across multiple sampling years. Pairwise comparison of RYCS among datasets revealed no significant associations either within or between lakes, suggesting that recruitment of lake whitefish is spatially asynchronous. There was no consistent correlation between pairwise agreement and the distance between datasets, and models to estimate the spatial scale of recruitment synchrony did not fit well to these data. This suggests that inter-annual recruitment variation of lake whitefish is asynchronous across broad spatial scales in the Great Lakes. While our method primarily evaluated year-to-year recruitment variation, it is plausible that recruitment of lake whitefish varies at coarser temporal scales (e.g. decadal). Nonetheless, our findings differ from research on some other Coregonus species and suggest that local biotic or density-dependent factors may contribute strongly to lake whitefish recruitment rather than inter-annual variability in broad-scale abiotic factors.


    Hartemann, F V; Albert, F; Anderson, G G; Anderson, S G; Bayramian, A J; Betts, S M; Chu, T S; Cross, R R; Ebbers, C A; Fisher, S E; Gibson, D J; Ladran, A S; Marsh, R A; Messerly, M J; O' Neill, K L; Semenov, V A; Shverdin, M Y; Siders, C W; McNabb, D P; Barty, C P; Vlieks, A E; Jongewaard, E N; Tantawi, S G; Raubenheimer, T O


    Recent progress in accelerator physics and laser technology have enabled the development of a new class of tunable gamma-ray light sources based on Compton scattering between a high-brightness, relativistic electron beam and a high intensity laser pulse produced via chirped-pulse amplification (CPA). A precision, tunable Mono-Energetic Gamma-ray (MEGa-ray) source driven by a compact, high-gradient X-band linac is currently under development and construction at LLNL. High-brightness, relativistic electron bunches produced by an X-band linac designed in collaboration with SLAC NAL will interact with a Joule-class, 10 ps, diode-pumped CPA laser pulse to generate tunable {gamma}-rays in the 0.5-2.5 MeV photon energy range via Compton scattering. This MEGa-ray source will be used to excite nuclear resonance fluorescence in various isotopes. Applications include homeland security, stockpile science and surveillance, nuclear fuel assay, and waste imaging and assay. The source design, key parameters, and current status are presented, along with important applications, including nuclear resonance fluorescence. In conclusion, we have optimized the design of a high brightness Compton scattering gamma-ray source, specifically designed for NRF applications. Two different parameters sets have been considered: one where the number of photons scattered in a single shot reaches approximately 7.5 x 10{sup 8}, with a focal spot size around 8 {micro}m; in the second set, the spectral brightness is optimized by using a 20 {micro}m spot size, with 0.2% relative bandwidth.

  8. Ecology of playa lakes

    Haukos, David A.; Smith, Loren M.


    Between 25,000 and 30,000 playa lakes are in the playa lakes region of the southern high plains (Fig. 1). Most playas are in west Texas (about 20,000), and fewer, in New Mexico, Oklahoma, Kansas, and Colorado. The playa lakes region is one of the most intensively cultivated areas of North America. Dominant crops range from cotton in southern areas to cereal grains in the north. Therefore, most of the native short-grass prairie is gone, replaced by crops and, recently, grasses of the Conservation Reserve Program. Playas are the predominant wetlands and major wildlife habitat of the region.More than 115 bird species, including 20 species of waterfowl, and 10 mammal species have been documented in playas. Waterfowl nest in the area, producing up to 250,000 ducklings in wetter years. Dominant breeding and nesting species are mallards and blue-winged teals. During the very protracted breeding season, birds hatch from April through August. Several million shorebirds and waterfowl migrate through the area each spring and fall. More than 400,000 sandhill cranes migrate through and winter in the region, concentrating primarily on the larger saline lakes in the southern portion of the playa lakes region.The primary importance of the playa lakes region to waterfowl is as a wintering area. Wintering waterfowl populations in the playa lakes region range from 1 to 3 million birds, depending on fall precipitation patterns that determine the number of flooded playas. The most common wintering ducks are mallards, northern pintails, green-winged teals, and American wigeons. About 500,000 Canada geese and 100,000 lesser snow geese winter in the playa lakes region, and numbers of geese have increased annually since the early 1980’s. This chapter describes the physiography and ecology of playa lakes and their attributes that benefit waterfowl.

  9. [Suggestion and hypnosis in hysteria].

    Berner, P


    Suggestive influences allow to resolve ambiguities. Normally they are only accepted if they correspond with the knowledge and believes of the subject. Under hypnosis or under the impact of serious psychic perturbations one may take up reality constructions which are not in conformity with these criteria. The restriction of consciousness and the ignoring of certain functions permitting this are the common basis of hypnosis and hysteria. But suggestions do not cause the later; they may only shape the symptomatology. Hypnosis can create a terrain facilitating the resolution of the problems underlying hysteria but it does not represent the treatment of hysteria.

  10. Effect of Subgrains on the Performance of Mono-Like Crystalline Silicon Solar Cells

    Su Zhou


    Full Text Available The application of Czochralski (Cz monocrystalline silicon material in solar cells is limited by its high cost and serious light-induced degradation. The use of cast multicrystalline silicon is also hindered by its high dislocation densities and high surface reflectance after texturing. Mono-like crystalline silicon is a promising material because it has the advantages of both mono- and multicrystalline silicon. However, when mono-like wafers are made into cells, the efficiencies of a batch of wafers often fluctuate within a wide range of >1% (absolute. In this work, mono-like wafers are classified by a simple process and fabricated into laser doping selective emitter cells. The effect and mechanism of subgrains on the performance of mono-like crystalline silicon solar cells are studied. The results show that the efficiency of mono-like crystalline silicon solar cells significantly depends on material defects that appear as subgrains on an alkaline textured surface. These subgrains have an almost negligible effect on the optical performance, shunt resistance, and junction recombination but significantly affect the minority carrier diffusion length and quantum efficiency within a long wavelength range. Finally, an average efficiency of 18.2% is achieved on wafers with hardly any subgrain but with a small-grain band.

  11. Chironomidae (Diptera in the Himalayan Lakes – A study of sub-fossil assemblages in the sediments of two high altitude lakes from Nepal

    Subodh Sharma


    Full Text Available Chironomid head capsules were identified from sediment cores taken from Lake Gokyo (4750 m and Lake Gosaikunda (4350 m in the east-central Himalaya, to determine taxonomic composition of chironomid assemblages over time.  The sedimentation rate of Lake Gosaikunda was estimated at 0.05 cm/yr and that of Gokyo was estimated at 0.07 cm/yr by 210Pb and 137Cs dating.  Micropsectra sp. was dominant in the sediments of both lakesLake Gokyo sediments also contained Pseudodiamesa sp., Eukiefferiella/Tvetenia sp., Orthocladius/Cricotopus sp. and Rheocricotopus sp.  The concentration of headcapsules was nearly an order of magnitude greater in the Lake Gosaikunda core, which contained mostly Micropsectra sp. and Pseudodiamesa sp.  These taxa are typical of cold oligotrophic lakes.  Differences in lake depth, dissolved minerals, plus epi- and hypolimnetic temperature and dissolved oxygen suggest that stratification and temperature-induced increases in primary production may affect chironomid assemblages in these pristine lakes.  Palaeolimnological studies of Himalayan lakes should include replicate cores within lake, to increase headcapsule sample sizes given potentially high rates of sedimentation from glacial runoff. Key words: high altitude lakes, Himalaya, Chironomidae, palaeolimnology, Nepal

  12. Evaluating the growth potential of sea lampreys (Petromyzon marinus) feeding on siscowet lake trout (Salvelinus namaycush) in Lake Superior

    Moody, E.K.; Weidel, B.C.; Ahrenstorff, T.D.; Mattes, W.P.; Kitchell, J.F.


    Differences in the preferred thermal habitat of Lake Superior lake trout morphotypes create alternative growth scenarios for parasitic sea lamprey (Petromyzon marinus) attached to lake trout hosts. Siscowet lake trout (Salvelinus namaycush) inhabit deep, consistently cold water (4–6 °C) and are more abundant than lean lake trout (Salvelinus namaycush) which occupy temperatures between 8 and 12 °C during summer thermal stratification. Using bioenergetics models we contrasted the growth potential of sea lampreys attached to siscowet and lean lake trout to determine how host temperature influences the growth and ultimate size of adult sea lamprey. Sea lampreys simulated under the thermal regime of siscowets are capable of reaching sizes within the range of adult sea lamprey sizes observed in Lake Superior tributaries. High lamprey wounding rates on siscowets suggest siscowets are important lamprey hosts. In addition, siscowets have higher survival rates from lamprey attacks than those observed for lean lake trout which raises the prospect that siscowets serve as a buffer to predation on more commercially desirable hosts such as lean lake trout, and could serve to subsidize lamprey growth.

  13. UVR induce optical changes and phosphorous release of lake water and macrophyte leachates in shallow Andean lakes

    Beatriz MODENUTTI


    Full Text Available We carried out laboratory experiments in order to study the effect of ultraviolet radiation (UVR on optical features and phosphorous release of Dissolved Organic Mater (DOM from lake water and macrophyte leachates. Lake water samples were obtained from lakes Escondido and El Trébol, and macrophytes (Potamogeton linguatus and Schoenoplectus californicus from their littoral zones. After UVR exposure, DOM from lake El Trébol seemed to react more quickly than that from Lake Escondido and this seems to be related with the degree of lability or aromaticity in the DOM bulk of each lake. Leachates from both macrophytes showed different absorbance spectra with differences in photochemical transformations after UVR exposure: S. californicus leachates exhibited the highest photodegradation. A significant Soluble Reactive Phosphorus (SRP release was observed in lake water after UVR exposure. Lake El Trébol showed the highest SRP concentrations, suggesting that the release of orthophosphate was favored by low molecular weight DOM. P. linguatus leachates have more dissolved phosphorus content than S. californicus ones and after UVR exposure, P. linguatus leachate did not react to UVR while S. californicus exhibited a decrease in SRP. However both macrophyte leachates showed the higher P release in darkness. The obtained results indicated that macrophyte leachates could contribute significantly to changes in the optical characteristics and in the nutrient content in shallow Andean lakes. An increasing input of P. linguatus leachates would produce DOM of high molecular size and a higher P release than S. californicus.

  14. Water level changes of high altitude lakes in Himalaya–Karakoram from ICESat altimetry

    Priyeshu Srivastava; Rakesh Bhambri; Prashant Kawishwar; D P Dobhal


    Himalaya–Karakoram (H–K) region hosts large number of high altitude lakes but are poorly gauged by in-situ water level monitoring method due to tough terrain conditions and poor accessibility. After the campaigns of ICESat during 2003–2009, now it is possible to achieve lake levels at decimetre accuracy. Therefore, in present study, high altitude lake levels were observed using ICESat/GLAS altimetry in H–K between 2003 and 2009 to generate baseline information. The study reveals that out of 13 lakes, 10 lakes show increasing trend of water levels at different rate (mean rate 0.173 m/y) whereas three lakes unveiled decreasing trend (mean rate −0.056 m/y). Out of five freshwater lakes, four lakes show an increasing trend of their level (mean rate 0.084 m/y) whereas comparatively six salt lakes (out of seven salt lakes) exhibited ∼3 times higher mean rate of lake level increase (0.233 m/y). These observed lake level rise can be attributed to the increased melt runoffs (i.e., seasonal snow and glacier melts) owing to the enhanced mean annual and seasonal air temperature during past decade in north-western (NW) Himalaya. Further, varied behaviours of lake level rises in inter- and intra-basins suggest that the local climatic fluctuations play prominent role along with regional and global climate in complex geographical system of NW Himalaya.

  15. A Holocene Sediment Record From Lake Elsinore, Southern California: Evidence for Relative Lake Level Change and the Onset of ENSO.

    Kirby, M. E.; Lund, S. P.; Poulsen, C. J.


    There are very few complete terrestrial, Holocene paleoclimate records from coastal southwestern North America. Lake Elsinore, located 120km southeast of Los Angeles, represents one of the only natural, non-playa lakes in the region. Furthermore, it is well documented that coastal southwestern North America is highly sensitive to changes in atmospheric circulation and its affect on regional hydrodynamics. As shown by Kirby et al. (in press), modern lake levels at Lake Elsinore respond directly to total annual precipitation, particularly winter season amounts. The lake is also located along the eastern Pacific Ocean where changes in ocean circulation and its thermal structure modulate the overlying atmosphere, and thus the adjacent continental climate. Here, we present two 7 meter sediment core records from Lake Elsinore spanning the entire Holocene. Although the cores are from the lake's littoral zone, they show surprisingly complete records with very little lithologic evidence for major hiatuses. A combination of sedimentological analyses (e.g., mass magnetic susceptibility (CHI); total percent carbonate; total organic matter) and lithologic descriptions provide insight to lake dynamics over the Holocene. Using the historical calibration between magnetic susceptibility and relative lake level (i.e., high lake levels = high CHI values and vice versa) from Kirby et al. (in press), we developed a first-order estimate of Holocene relative lake levels for Lake Elsinore. The historic calibration is extrapolated through the sediment record based on the assumption that, like today, first order lake level change is directly related to precipitation amount. Both total percent carbonate and total organic matter support our historical calibration between CHI and lake level. Our data suggest a relative increase in lake levels during the mid-Holocene (ca. 8,000 cal yr BP) and through to the present day. From this observation, we hypothesize that regional hydrology as linked to

  16. Can lake sensitivity to desiccation be predicted from lake geometry?

    Torabi Haghighi, Ali; Menberu, Meseret Walle; Aminnezhad, Mousa; Marttila, Hannu; Kløve, Bjørn


    Declining lake levels (Aral Sea syndrome) can be caused by changes in climate, increased water use or changed regulation patterns. This paper introduces a novel lake geometry index (LGI) to quantify lake hydrological characteristics. The index was developed using a large representative dataset of lake hypsographic characteristics from 152 lakes and man-made reservoirs. Using the LGI index, lakes can be classified into five groups: groups 1-4 when LGI is 0.5-2.5, 2.5-4.5, 4.5-6.5 and 6.5-8.5, respectively, and group 5 when LGI is >8.5. Naturally shallow and vast lakes and wetlands fall into the first group and deep man-made reservoirs in narrow valleys are in group 5. The response of three different lake systems (LGI 0.75, 2.75 and 6.5) to different water flow scenarios was then simulated using the water balance equation. From this, the index 'potential lake area' (Apot) was developed to show lake responses to changed hydro-climatological conditions. Apot and LGI can be used to classify lakes into open or closed systems. Simulations showed that lakes with low LGI have a shorter response time to flow and climate changes. As a result, the impact of water balance restoration is faster for lakes with low LGI than for lakes with high LGI. The latter are also more vulnerable to climate variation and change.

  17. Vasculitis neuropathy mimicking lower limb mono-radiculopathy: a study and follow-up of 8 cases.

    Lozeron, Pierre; Lacroix, Catherine; Michon, Mathilde; Theaudin, Marie; Petit Lacour, Marie-Christine; Denier, Christian; Adams, David


    The aim of this study was to describe misleading lower limb mono radiculopathy revealing peripheral nerve vasculitis. Retrospective review of eight patients with biopsy confirmed vasculitis presenting as mono-radicululopathy in a tertiary referral centre dedicated to patients with rare peripheral neuropathies. Patients presented with chronic (6/8) or acute (n = 2) radiculopathy in L4, L5 or S1 territories associated with subtle systemic signs. A diagnostic workup was performed because of secondary motor deficit, the absence of clear radicular compression or failure of initial treatment focused on pain relief. In all, nerve conduction studies showed signs of asymmetrical axonal peripheral neuropathy (mononeuritis multiplex). Necrotizing vasculitis was eventually confirmed by peripheral nerve biopsy. Biological markers of inflammation or eosinophilia were present in 5/8 and a progressive motor deficit (7/8) is suggestive of the diagnosis. Under steroid treatment, all patients improved during a mean of 2 years 6 months of follow-up (Mean Rankin score improvement 1.9 point), but five relapsed including three mononeuritis multiplex, and one had acral necrosis. Vasculitis presenting as LL radiculopathy is rare; EMG studies with signs of mononeuritis multiplex and nerve biopsy studies are useful for making the diagnosis.

  18. The Mono Arch, eastern Sierra region, California: Dynamic topography associated with upper-mantle upwelling?

    Jayko, A.S.


    A broad, topographic flexure localized east of and over the central and southern Sierra Nevada, herein named the Mono Arch, apparently represents crustal response to lithospheric and/or upper-mantle processes, probably dominated by mantle upwelling within the continental interior associated Pacific-North American plate-boundary deformation. This zone of flexure is identified through comparison between the topographic characteristics of the active Cascade volcanic arc and backarc regions with the analogous former arc and backarc in the Sierra Nevada and eastern Sierra Nevada. Serial topographic profiles measured normal to the modern Cascade backarc reveal an accordance of topographic lows defined by valley floors with an average minimum elevation of ???1400-1500m for over 175km to the southeast. Although the accordance drops in elevation slightly to the south, the modern Cascade backarc region is remarkably level, and is characterized by relief up to ???750m above this baseline elevation. By contrast, serial topographic profiles over the former arc and backarc transitions of the eastern Sierra region exhibit a regional anticlinal warping defined by accordant valley floors and by a late Miocene-early Pliocene erosion surface and associated deposits. The amplitude of this flexure above regionally flat baseline elevations to the east varies spatially along the length of the former Sierran arc, with a maximum of ???1000m centred over the Bridgeport Basin. The total zone of flexure is approximately 350km long N-S and 100km wide E-W, and extends from Indian Wells Valley in the south to the Sonora Pass region in the north. Previous geophysical, petrologic, and geodetic studies suggest that the Mono Arch overlies a zone of active mantle upwelling. This region also represents a zone crustal weakness formerly exploited by the middle-to-late Miocene arc and is presently the locus of seismic and volcanic activities. This seismic zone, which lies east of the Sierra Nevada block

  19. Halls Lake 1990

    National Oceanic and Atmospheric Administration, Department of Commerce — Salt marsh habitats along the shoreline of Halls Lake are threatened by wave erosion, but the reconstruction of barrier islands to reduce this erosion will modify or...

  20. Sunk Lake Natural Area

    US Fish and Wildlife Service, Department of the Interior — The Sunk Lake Natural Area Management Plan guides the long-range development of the Natural Area by identifying and integrating appropriate habitats, management...

  1. Lake Transect : 1986

    US Fish and Wildlife Service, Department of the Interior — This document summarizes transect surveys that were done at four different lakes on St. Vincent National Wildlife Refuge in 1986. Lists of the plant species found at...

  2. Lake Transect : 1988

    US Fish and Wildlife Service, Department of the Interior — This document summarizes transect surveys that were done at four different lakes on St. Vincent National Wildlife Refuge in 1988. Lists of the plant species found at...

  3. Lake Transect : 1989

    US Fish and Wildlife Service, Department of the Interior — This document summarizes transect surveys that were done at four different lakes on St. Vincent National Wildlife Refuge in 1989. Lists of the plant species found...

  4. History of Lake Andes

    US Fish and Wildlife Service, Department of the Interior — Information about the history and management of Lake Andes is compiled in this report. It is intended to help future refuge managers become acquainted with the...

  5. Lake Level Reconstructions

    National Oceanic and Atmospheric Administration, Department of Commerce — Records of past lake levels, mostly related to changes in moisture balance (evaporation-precipitation). Parameter keywords describe what was measured in this data...

  6. Great Lakes Ice Charts

    National Oceanic and Atmospheric Administration, Department of Commerce — Charts show ice extent and concentration three times weekly during the ice season, for all lakes except Ontario, from the 1973/74 ice season through the 2001/2002...

  7. Chase Lake Wetland Management District, Chase Lake National Wildlife Refuge, Chase Lake Prairie Project: Annual narrative report: 1997

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Chase Lake WMD, Chase Lake NWR, Chase Lake Prairie Project, and Halfway Lake NWR outlines Refuge accomplishments during the 1997...

  8. High-pressure Raman study of mono-L-alaninium nitrate crystals

    Soares, R. A.; Lima, R. J. C.; Façanha Filho, P. F.; Freire, P. T. C.; Lima, J. A.; da Silva Filho, J. G.


    Single-crystal samples of mono-L-alaninium nitrate, known for its non-linear optical properties, have been studied by Raman spectroscopy in a diamond-anvil cell up to pressures of 7.4 GPa. The data acquired in this study are consistent with the hypothesis that a phase transition takes place between 3.5 and 4.1 GPa, as suggested by the change of Raman profile in both the low wavenumber and the internal modes spectral regions. A detailed analysis of the vibrational properties in the wavenumber region below 130 cm-1 including the dependence of the wavenumber of the observed modes as a function of pressure as well a comparison with previous papers reporting the Raman spectra of the L-alanine is presented. Correlation between hydrogen bond at room pressure and the occurrence of the phase transition with pressure variation was proposed giving new insights about the problem. Upon decompression to ambient pressure the original spectra were recovered indicating that the phase transition is reversible.

  9. Prediction of mono- and polycyclic aromatic hydrocarbon degradation in spiked soils using cyclodextrin extraction

    Allan, Ian J. [School of Environmental Sciences, University of East Anglia, Norwich NR4 7TJ (United Kingdom); Semple, Kirk T. [Department of Environmental Sciences, Lancaster University, LA1 4YQ (United Kingdom); Hare, Rina [Alcontrol Laboratories, Chester CH5 3US (United Kingdom); Reid, Brian J. [Alcontrol Laboratories, Chester CH5 3US (United Kingdom)]. E-mail:


    In this study, an aqueous-based hydroxypropyl-{beta}-cyclodextrin (HPCD) extraction technique was assessed for its capacity to determine the microbially degradable fraction of mono- and polycyclic aromatic hydrocarbons in four dissimilar soils. A linear relationship (slope = 0.90; R {sup 2} = 0.89), approaching 1:1 between predicted and observed phenanthrene mineralization, was demonstrated for the cyclodextrin extraction; however, the water only extraction underestimated the microbially available fraction by a factor of three (slope = 3.35; R {sup 2} = 0.64). With respect to determining the mineralizable fraction of p-cresol in soils, the cyclodextrin extraction (slope = 0.94; R {sup 2} = 0.84) was more appropriate than the water extraction (slope = 1.50; R {sup 2} = 0.36). Collectively, these results suggested that the cyclodextrin extraction technique was suitable for the prediction of the mineralizable fraction of representative PAHs and phenols present in dissimilar soils following increasing soil-contaminant contact times. The assessment of the microbial availability of contaminants in soils is important for a more representative evaluation of soil contamination. - An aqueous-based HPCD extraction technique was more appropriate than the water extraction in prediction of the mineralizable fraction of phenanthrene and p-cresol present in a range of dissimilar soils.

  10. Mono-(2-Ethylhexyl Phthalate Promotes Pro-Labor Gene Expression in the Human Placenta.

    Ximi K Wang

    Full Text Available Women exposed to phthalates during pregnancy are at increased risk for delivering preterm, but the mechanism behind this relationship is unknown. Placental corticotropin-releasing hormone (CRH and cyclooxygenase-2 (COX-2 are key mediators of parturition and are regulated by the non-canonical NF-kB (RelB/p52 signaling pathway. In this study, we demonstrate that one of the major phthalate metabolites, mono-(2-ethylhexyl-phthalate (MEHP, increased CRH and COX-2 mRNA and protein abundance in a dose-dependent manner in primary cultures of cytotrophoblast. This was coupled with an increase in nuclear import of RelB/p52 and its association with the CRH and COX-2 promoters. Silencing of NF-kB inducing kinase, a central signaling component of the non-canonical NF-kB pathway, blocked MEHP-induced upregulation of CRH and COX-2. These results suggest a potential mechanism mediated by RelB/p52 by which phthalates could prematurely induce pro-labor gene activity and lead to preterm birth.

  11. Is Lake Tahoe Terminal?

    Coats, R. N.; Reuter, J.; Heyvaert, A.; Lewis, J.; Sahoo, G. B.; Schladow, G.; Thorne, J. H.


    Lake Tahoe, an iconic ultra-oligotrophic lake in the central Sierra Nevada, has been studied intensively since 1968, with the goal of understanding and ultimately controlling its eutrophication and loss of clarity. Research on the lake has included a) periodic profiles of primary productivity, nutrients, temperature, and plankton; b) Secchi depth; c) nutrient limitation experiments; d) analysis of sediment cores; e) radiocarbon dating of underwater in-place tree stumps; g) analysis of long-term temperature trends. Work in its watershed has included a) monitoring of stream discharge, sediment and nutrients at up to 20 stream gaging stations; b) monitoring of urban runoff water quality at selected sites; c) development of a GIS data base, including soils, vegetation, and land use. Based on these studies, we know that a) primary productivity in the lake is limited by phosphorus, and continues to increase; b) the loss of clarity continues, but at a declining rate; c) the lake has been warming since 1970, and its resistance to deep mixing is increasing; d) historically the lake level drops below the outlet elevation about one year in seven; e) 6300 to 4300 yrs BP lake level was below the present outlet elevation long enough for large trees to grow; f) the date of the peak snowmelt runoff is shifting toward earlier dates; g) after accounting for annual runoff, loads of nutrients and suspended sediment have declined significantly in some basin streams since 1980. Downscaled outputs from GCM climatic models have recently been used to drive hydrologic models and a lake clarity model, projecting future trends in the lake and watersheds. Results show a) the temperature and thermal stability will likely continue to increase, with deep mixing shutting down in the latter half of this century; b) the lake may drop below the outlet for an extended period beginning about 2085; c) the annual snowpack will continue to decline, with earlier snowmelt and shift from snowfall to rain; d


    Schulz, Klaus J.


    The mineral-resource potential of the Whisker Lake Wilderness in northeastern Wisconsin was evaluated. Only a strip along the southwest corner of the wilderness is assessed as having probable mineral-resource potential. If mineral deposits exist, they probably are of the massive sulfide type. The geologic terrain precludes the presence of fossil fuel resources. Sand and gravel and peat in swampy lowlands are the only resources of the Whisker lake Wilderness.

  13. Similar resilience attributes in lakes with different management practices.

    Didier L Baho

    Full Text Available Liming has been used extensively in Scandinavia and elsewhere since the 1970s to counteract the negative effects of acidification. Communities in limed lakes usually return to acidified conditions once liming is discontinued, suggesting that liming is unlikely to shift acidified lakes to a state equivalent to pre-acidification conditions that requires no further management intervention. While this suggests a low resilience of limed lakes, attributes that confer resilience have not been assessed, limiting our understanding of the efficiency of costly management programs. In this study, we assessed community metrics (diversity, richness, evenness, biovolume, multivariate community structure and the relative resilience of phytoplankton in limed, acidified and circum-neutral lakes from 1997 to 2009, using multivariate time series modeling. We identified dominant temporal frequencies in the data, allowing us to track community change at distinct temporal scales. We assessed two attributes of relative resilience (cross-scale and within-scale structure of the phytoplankton communities, based on the fluctuation frequency patterns identified. We also assessed species with stochastic temporal dynamics. Liming increased phytoplankton diversity and richness; however, multivariate community structure differed in limed relative to acidified and circum-neutral lakes. Cross-scale and within-scale attributes of resilience were similar across all lakes studied but the contribution of those species exhibiting stochastic dynamics was higher in the acidified and limed compared to circum-neutral lakes. From a resilience perspective, our results suggest that limed lakes comprise a particular condition of an acidified lake state. This explains why liming does not move acidified lakes out of a "degraded" basin of attraction. In addition, our study demonstrates the potential of time series modeling to assess the efficiency of restoration and management outcomes through

  14. H2/D2 exchange reaction on mono-disperse Pt clusters: enhanced activity from minute O2 concentrations

    Riedel, Jakob Nordheim; Rötzer, Marian David; Jørgensen, Mikkel;


    The H2/D2 exchange reaction was studied on mono-disperse Pt8 clusters in a μ-reactor. The chemical activity was studied at temperatures varying from room temperature to 180 °C using mass spectrometry. It was found that minute amounts of O2 in the gas stream increased the chemical activity...... significantly. XPS and ISS before and after reaction suggest little or no sintering during reaction. A reaction pathway is suggested based on DFT. H2 desorption is identified as the rate-limiting step and O2 is confirmed as the source of the increased activity. The binding energy of platinum atoms in a SiO2...... supported Pt8 cluster is found to be comparable to the interatomic binding energies of bulk platinum, underlining the stability of the model system....

  15. Resilience and Restoration of Lakes

    Kathryn L. Cottingham


    Full Text Available Lake water quality and ecosystem services are normally maintained by several feedbacks. Among these are nutrient retention and humic production by wetlands, nutrient retention and woody habitat production by riparian forests, food web structures that cha nnel phosphorus to consumers rather than phytoplankton, and biogeochemical mechanisms that inhibit phosphorus recycling from sediments. In degraded lakes, these resilience mechanisms are replaced by new ones that connect lakes to larger, regional economi c and social systems. New controls that maintain degraded lakes include runoff from agricultural and urban areas, absence of wetlands and riparian forests, and changes in lake food webs and biogeochemistry that channel phosphorus to blooms of nuisance al gae. Economic analyses show that degraded lakes are significantly less valuable than normal lakes. Because of this difference in value, the economic benefits of restoring lakes could be used to create incentives for lake restoration.

  16. Suggestions on photons and fermions

    Alvargonzalez, R


    In this paper we suggest a configuration of photons consistent with a spin $\\hbar$, and a configuration of the fermions coherent with a spin $\\hbar/2$. These suggested configurations open the way to further analyses which lead to the following conclusions: - There cannot exist elementary particles of spin $\\hbar/2$ with a mass inferior to $1m_e$ or with a radius greater than $1l_e$. - The electrostatic force derives from the centrifugal forces inherent to the spin and are propagated by photons. - The derivation of the electrostatic force explains the existence of positive and negative charges and Coulomb's law. - The enormous differences between the centrifugal forces and the centripetal forces at the surface of the protons give rise to quantic fluctuations of space which generate the energy flows necessary for equilibrium. These energy flows can explain gravitation and the strong force. - The mass of the proton, $m_p$, and the mass of the neutron, $m_n$, must each have a concrete value required for the cohes...

  17. Is Lake Chabot Eutrophic?

    Pellegrini, K.; Logan, J.; Esterlis, P.; Lew, A.; Nguyen, M.


    Introduction/Abstract: Lake Chabot is an integral part of the East Bay watershed that provides habitats for animals and recreation for humans year-round. Lake Chabot has been in danger of eutrophication due to excessive dumping of phosphorous and nitrogen into the water from the fertilizers of nearby golf courses and neighboring houses. If the lake turned out to be eutrophified, it could seriously impact what is currently the standby emergency water supply for many Castro Valley residents. Eutrophication is the excessive richness of nutrients such as nitrogen and phosphorus in a lake, usually as a result of runoff. This buildup of nutrients causes algal blooms. The algae uses up most of the oxygen in the water, and when it dies, it causes the lake to hypoxify. The fish in the lake can't breathe, and consequently suffocate. Other oxygen-dependant aquatic creatures die off as well. Needless to say, the eutrophication of a lake is bad news for the wildlife that lives in or around it. The level of eutrophication in our area in Northern California tends to increase during the late spring/early summer months, so our crew went out and took samples of Lake Chabot on June 2. We focused on the area of the lake where the water enters, known on the map as Honker Bay. We also took readings a ways down in deeper water for comparison's sake. Visually, the lake looked in bad shape. The water was a murky green that glimmered with particulate matter that swirled around the boat as we went by. In the Honker Bay region where we focused our testing, there were reeds bathed in algae that coated the surface of the lake in thick, swirling patterns. Surprisingly enough, however, our test results didn't reveal any extreme levels of phosphorous or nitrogen. They were slightly higher than usual, but not by any significant amount. The levels we found were high enough to stimulate plant and algae growth and promote eutrophication, but not enough to do any severe damage. After a briefing with a

  18. Surface microlayers on temperate lowland lakes

    Båstrup-Spohr, Lars; Stæhr, Peter Anton


    with subsurface water (SSW) in an eutrophic and a mesotrophic lake from April to September 2007. Wind, solar irradiance, and lake temperature were followed continuously. Samples were analyzed for organic and inorganic compounds as well as for photosynthesis and respiration. Most compounds were enriched in the SML......At the air-water interface material, organisms accumulate and form a thin layer of organic and inorganic material called the surface microlayer (SML). In order to investigate the development, composition, and metabolism of SML on lakes, samples were collected using a screen sampler along....... Enrichment factors of several compounds were higher at low bulk water concentrations, suggesting that atmospheric deposition then contributed relatively more to concentrations in the SML. Increasing temperature significantly decreased SML enrichment of TOC (total organic carbon), related to changes in TOC...

  19. Tewaukon – Clouds LakeLake Elsie – Storm Lake and Wild Rice Refuges Narrative Reports : 1939-1956 : From Sand Lake National Wildlife Refuge

    US Fish and Wildlife Service, Department of the Interior — These narrative reports summarize refuge activities from 1939 to 1956 for Lake Tewaukon Refuge, Clouds Lake Refuge, Lake Elsie Refuge, Storm Lake Refuge, Wild Rice...


    The Product is the paper "Pulp and Paper Mills as Sources of Toxaphene to Lake Superior and Northern Lake Michigan" published in the Journal of Great Lakes Research, 25(2):383-394 International Association of Great Lakes 1999.

  1. Glacial lake inventory and lake outburst potential in Uzbekistan.

    Petrov, Maxim A; Sabitov, Timur Y; Tomashevskaya, Irina G; Glazirin, Gleb E; Chernomorets, Sergey S; Savernyuk, Elena A; Tutubalina, Olga V; Petrakov, Dmitriy A; Sokolov, Leonid S; Dokukin, Mikhail D; Mountrakis, Giorgos; Ruiz-Villanueva, Virginia; Stoffel, Markus


    Climate change has been shown to increase the number of mountain lakes across various mountain ranges in the World. In Central Asia, and in particular on the territory of Uzbekistan, a detailed assessment of glacier lakes and their evolution over time is, however lacking. For this reason we created the first detailed inventory of mountain lakes of Uzbekistan based on recent (2002-2014) satellite observations using WorldView-2, SPOT5, and IKONOS imagery with a spatial resolution from 2 to 10m. This record was complemented with data from field studies of the last 50years. The previous data were mostly in the form of inventories of lakes, available in Soviet archives, and primarily included localized in-situ data. The inventory of mountain lakes presented here, by contrast, includes an overview of all lakes of the territory of Uzbekistan. Lakes were considered if they were located at altitudes above 1500m and if lakes had an area exceeding 100m(2). As in other mountain regions of the World, the ongoing increase of air temperatures has led to an increase in lake number and area. Moreover, the frequency and overall number of lake outburst events have been on the rise as well. Therefore, we also present the first outburst assessment with an updated version of well-known approaches considering local climate features and event histories. As a result, out of the 242 lakes identified on the territory of Uzbekistan, 15% are considered prone to outburst, 10% of these lakes have been assigned low outburst potential and the remainder of the lakes have an average level of outburst potential. We conclude that the distribution of lakes by elevation shows a significant influence on lake area and hazard potential. No significant differences, by contrast, exist between the distribution of lake area, outburst potential, and lake location with respect to glaciers by regions. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Evidence of Lake Trout reproduction at Lake Michigan's mid-lake reef complex

    Janssen, J.; Jude, D.J.; Edsall, T.A.; Paddock, R.W.; Wattrus, N.; Toneys, M.; McKee, P.


    The Mid-Lake Reef Complex (MLRC), a large area of deep (> 40 m) reefs, was a major site where indigenous lake trout (Salvelinus namaycush) in Lake Michigan aggregated during spawning. As part of an effort to restore Lake Michigan's lake trout, which were extirpated in the 1950s, yearling lake trout have been released over the MLRC since the mid-1980s and fall gill net censuses began to show large numbers of lake trout in spawning condition beginning about 1999. We report the first evidence of viable egg deposition and successful lake trout fry production at these deep reefs. Because the area's existing bathymetry and habitat were too poorly known for a priori selection of sampling sites, we used hydroacoustics to locate concentrations of large fish in the fall; fish were congregating around slopes and ridges. Subsequent observations via unmanned submersible confirmed the large fish to be lake trout. Our technological objectives were driven by biological objectives of locating where lake trout spawn, where lake trout fry were produced, and what fishes ate lake trout eggs and fry. The unmanned submersibles were equipped with a suction sampler and electroshocker to sample eggs deposited on the reef, draw out and occasionally catch emergent fry, and collect egg predators (slimy sculpin Cottus cognatus). We observed slimy sculpin to eat unusually high numbers of lake trout eggs. Our qualitative approaches are a first step toward quantitative assessments of the importance of lake trout spawning on the MLRC.

  3. Holocene Lake Records on Kamchatka

    Diekmann, Bernhard; Biskaborn, Boris; Chapligin, Bernhard; Dirksen, Oleg; Dirksen, Veronika; Hoff, Ulrike; Meyer, Hanno; Nazarova, Larisa


    palaeoecologocal responses in different lake systems under same climatic boundary conditions. Our findings give evidence of longterm climate changes that suggest the existence of a warm and humid early Holocene climate optimum between roughly 9.0 and 4.5 ka BP, followed by climate deterioration of the neoglacial epoch in concert with summer cooling, glacial advances, and enhanced continentality. Two strong cooling episodes punctuated late Holocene climate development between 4.5 and 3.5 ka BP and during the last millennium, marking the prelude of neoglacial cooling and the Little Ice Age. This general development of Holocene climate on Kamchatka is in line with environmental changes in the neighbouring Sea of Okhotsk, where the pattern of sea-ice dynamics is consistent with early Holocene warmth and Neoglacial climate cooling. While the marine records from the Sea of Okhotsk mainly reflect winter conditions, our findings show that summer climate on Kamchatka shows a similar trend of temporal change. Holocene climate variability on Kamchatka was mainly driven by external insolation forcing, changes in solar activity, and internal climate forcing. The latter is dictated by by the relative position of the Aleutan Low in response to the prevailing modes of Pacific Decadal Oscillation and the Arctic Oscillation that both control the influence of maritime or continental air masses and the intensity of rain- or snow-bringing cyclones.

  4. Lake-catchment systems and sediment information in Baikal district (Siberia and Mongolia)



    Sediment information is closely related to a lake-catchment system. Lake Baikal and Lake Khuvsgul in the Baikal depression have shown different sedimentary trends during the past 800 ka; the sediment discharge (sedimentation rate) in Baikal basically followed the global climatic change, whereas that in Khuvsgul did not always do so. An elementary mathematical model is used to explain the difference, considering changes in the catchment area and water level. Numerical calculations based on the model suggest that sedimentary conditions are closely related to changes in the water level and erosion area, which probably had a signiifcant inlfuence on Lake Khuvsgul and little inlfuence on Lake Baikal.

  5. Temperature dependence of the relationship between pCO2 and dissolved organic carbon in lakes

    Pinho, L.


    The relationship between the partial pressure of carbon dioxide (pCO2) and dissolved organic carbon (DOC) concentration in Brazilian lakes, encompassing 225 samples across a wide latitudinal range in the tropics, was tested. Unlike the positive relationship reported for lake waters, which was largely based on temperate lakes, we found no significant relationship for low-latitude lakes (< 33°), despite very broad ranges in both pCO2 and DOC levels. These results suggest substantial differences in the carbon cycling of low-latitude lakes, which must be considered when upscaling limnetic carbon cycling to global scales.

  6. Lake Morphometry for NHD Lakes in Ohio Region 5 HUC

    U.S. Environmental Protection Agency — Lake morphometry metrics are known to influence productivity in lakes and are important for building various types of ecological and environmental models of lentic...

  7. Lake Morphometry for NHD Lakes in California Region 18 HUC

    U.S. Environmental Protection Agency — Lake morphometry metrics are known to influence productivity in lakes and are important for building various types of ecological and environmental models of lentic...

  8. Lake Morphometry for NHD Lakes in Tennessee Region 6 HUC

    U.S. Environmental Protection Agency — Lake morphometry metrics are known to influence productivity in lakes and are important for building various types of ecological and environmental models of lentic...


    Studies on phytoplankton species diversity and abundance were carried out in 8 selected satellite lakes within the Lake ... species of blue green algae such as Spirulina spp. are sources of ... scientific and conservation interests. This study ...

  10. A dynamic multimedia environmental and bioaccumulation model for brominated flame retardants in Lake Huron and Lake Erie, USA.

    Lim, Dong-Hee; Lastoskie, Christian M


    Polybrominated biphenyls (PBBs) and polybrominated diphenyl ethers (PBDEs) may pose a worldwide pollution problem because of their persistence, long-range transport capability, and predisposition to bioaccumulate. The ubiquitous presence of PBBs and PBDEs has heightened interest in determination of their fate. We report results for a fugacity-based dynamic environmental and bioaccumulation model of the fate of hexabromobiphenyl (hexaBB) discharged into the Saginaw Bay region of Lake Huron, USA. We calculated transient fugacity profiles of hexaBB in Lake Huron and Lake Erie water and sediment during the 1970s, 1980s, and 1990s. The hexaBB concentrations in the environmental compartments were used as inputs for a dynamic bioaccumulation model of Lake Huron and Lake Erie aquatic biota. The model results indicate that the sediment compartments of Lakes Huron and Erie serve as reservoirs for the accumulation and slow transfer of hexaBB to the food web constituents of these lakes. We present bioaccumulation factors (BAFs) and compare the predicted hexaBB concentrations in lake trout from the bioaccumulation model with measurements during the period 1980 to 2000. An uncertainty analysis for this model suggests that errors associated with input parameter uncertainty can be reduced by refining estimates of the sediment degradation half-life of hexaBB. The corroborated PBB model has carryover application for modeling the fate of polybrominated diphenyl ether (PBDE) contaminants in the Great Lakes. By fitting model outputs to field measurement data using the transformed least square fit method, we report estimations of 2,2',4,4'-tetrabromodiphenyl ether (BDE-47) emission rates into the Lake Huron and Lake Erie watershed areas.

  11. Cormorant predation on PIT-tagged lake fish

    Christian Skov


    Full Text Available The present study use data from recovered PIT (Passive Integrated Transponder tags to explore species- and size-specific annual predation rates by cormorants on three common lacustrine fishes (size range 120-367 mm in a European lake; roach (Rutilus rutilus, common bream (Abramis brama and perch (Perca fluviatilis. In addition, we quantify the level of age/size truncation that cormorant predation could introduce in a population of perch, an important fish for recreational angling as well as for trophic interactions and ecosystem function in European lakes. Based on three years of PIT tagging of fish in lake Viborg and subsequent recoveries of PIT tags from nearby cormorant roosting and breeding sites, we show that cormorants are major predators of roach, bream and perch within the size groups we investigated and for all species larger individuals had higher predation rates. Perch appear to be the most vulnerable of the three species and based on a comparison with mortality estimates from lakes without significant avian predation, this study suggest that predation from cormorants can induce age/size truncation in lake Viborg, leaving very few larger perch in the lake. This truncation reduces the likelihood of anglers catching a large perch and may also influence lower trophic levels in the lake and thus turbidity as large piscivorous perch often play an important structuring role in lake ecosystem functioning.

  12. The conserved macrodomains of the non-structural proteins of Chikungunya virus and other pathogenic positive strand RNA viruses function as mono-ADP-ribosylhydrolases.

    Eckei, Laura; Krieg, Sarah; Bütepage, Mareike; Lehmann, Anne; Gross, Annika; Lippok, Barbara; Grimm, Alexander R; Kümmerer, Beate M; Rossetti, Giulia; Lüscher, Bernhard; Verheugd, Patricia


    Human pathogenic positive single strand RNA ((+)ssRNA) viruses, including Chikungunya virus, pose severe health problems as for many neither efficient vaccines nor therapeutic strategies exist. To interfere with propagation, viral enzymatic activities are considered potential targets. Here we addressed the function of the viral macrodomains, conserved folds of non-structural proteins of many (+)ssRNA viruses. Macrodomains are closely associated with ADP-ribose function and metabolism. ADP-ribosylation is a post-translational modification controlling various cellular processes, including DNA repair, transcription and stress response. We found that the viral macrodomains possess broad hydrolase activity towards mono-ADP-ribosylated substrates of the mono-ADP-ribosyltransferases ARTD7, ARTD8 and ARTD10 (aka PARP15, PARP14 and PARP10, respectively), reverting this post-translational modification both in vitro and in cells. In contrast, the viral macrodomains possess only weak activity towards poly-ADP-ribose chains synthesized by ARTD1 (aka PARP1). Unlike poly-ADP-ribosylglycohydrolase, which hydrolyzes poly-ADP-ribose chains to individual ADP-ribose units but cannot cleave the amino acid side chain - ADP-ribose bond, the different viral macrodomains release poly-ADP-ribose chains with distinct efficiency. Mutational and structural analyses identified key amino acids for hydrolase activity of the Chikungunya viral macrodomain. Moreover, ARTD8 and ARTD10 are induced by innate immune mechanisms, suggesting that the control of mono-ADP-ribosylation is part of a host-pathogen conflict.

  13. 40 CFR 721.3130 - Sulfuric acid, mono-C9-11-alkyl esters, sodium salts.


    ... 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... acid, mono-C9-11-alkyl esters, sodium salts (PMN P-01-149; CAS No. 84501-49-5) is subject to reporting...



    The work investigates ethoxylation of glycerol mono oleate (GMO) performed in the presence of an alkaline catalyst. Glycerol mono oleate applied was derivated from Indonesian palm oil. The reaction was conducted with variation of Glycerol mono oleate : ethylene oxide ratio, temperature, and catalyst concentration. Forier Transform Infra Red (FTIR) and Nuclear Magnetic Resonance (NMR) analysis showed products with degrees of ethoxylation n=2 and n=3. FTIR analysis of products gave a new peak a...


    Langton, C.; Stefanko, D.


    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.

  16. Selective mono-radioiodination and characterization of a cell-penetrating peptide. L-Tyr-maurocalcine

    Ahmadi, Mitra; Bacot, Sandrine; Perret, Pascale; Riou, Laurent; Ghezzi, Catherine [Universite Joseph Fourier, Grenoble (France); INSERM U1039, Grenoble (France). Radiopharmaceutiques Biocliniques; Poillot, Cathy; Cestele, Sandrine [INSERM U836, Grenoble (France). Grenoble Inst. of Neuroscience; Universite Joseph Fourier, Grenoble (France); Desruet, Marie-Dominique [INSERM U1039, Grenoble (France). Radiopharmaceutiques Biocliniques; Couvet, Morgane; Bourgoin, Sandrine; Seve, Michel [CRI-INSERM U823, Grenoble (France). Inst. of Albert Bonniot; Universite Joseph Fourier, Grenoble (France); Waard, Michel de [INSERM U836, Grenoble (France). Grenoble Inst. of Neuroscience; Universite Joseph Fourier, Grenoble (France); Smartox Biotechnologies, Grenoble (France)


    Mono-and poly-iodinated peptides form frequently during radioiodination procedures. However, the formation of a single species in its mono-iodinated form is essential for quantitative studies such as determination of tissue concentration or image quantification. Therefore, the aim of the present study was to define the optimal experimental conditions in order to exclusively obtain the mono-iodinated form of L-maurocalcine (L-MCa). L-MCa is an animal venom toxin which was shown to act as a cell-penetrating peptide. In order to apply the current direct radioiodination technique using oxidative agents including chloramine T, Iodo-Gen {sup registered} or lactoperoxidase, an analogue of this peptide containing a tyrosine residue (Tyr-L-MCa) was synthesized and was shown to fold/oxidize properly. The enzymatic approach using lactoperoxidase/H{sub 2}O{sub 2} was found to be the best method for radioiodination of Tyr-L-MCa. MALDI-TOF mass spectrometry analyses were then used for identification of the chromatographic eluting components of the reaction mixtures. We observed that the production of different radioiodinated species depended upon the reaction conditions. Our results successfully described the experimental conditions of peptide radioiodination allowing the exclusive production of the mono-iodinated form with high radiochemical purity and without the need for a purification step. Mono-radioiodination of L-Tyr-MCa will be crucial for future quantitative studies, investigating the mechanism of cell penetration and in vivo biodistribution.

  17. Simulating 2,368 temperate lakes reveals weak coherence in stratification phenology

    Read, Jordan S.; Winslow, Luke A.; Hansen, Gretchen J. A.; Van Den Hoek, Jamon; Hanson, Paul C.; Bruce, Louise C; Markfort, Corey D.


    Changes in water temperatures resulting from climate warming can alter the structure and function of aquatic ecosystems. Lake-specific physical characteristics may play a role in mediating individual lake responses to climate. Past mechanistic studies of lake-climate interactions have simulated generic lake classes at large spatial scales or performed detailed analyses of small numbers of real lakes. Understanding the diversity of lake responses to climate change across landscapes requires a hybrid approach that couples site-specific lake characteristics with broad-scale environmental drivers. This study provides a substantial advancement in lake ecosystem modeling by combining open-source tools with freely available continental-scale data to mechanistically model daily temperatures for 2,368 Wisconsin lakes over three decades (1979-2011). The model accurately predicted observed surface layer temperatures (RMSE: 1.74°C) and the presence/absence of stratification (81.1% agreement). Among-lake coherence was strong for surface temperatures and weak for the timing of stratification, suggesting individual lake characteristics mediate some - but not all - ecologically relevant lake responses to climate.

  18. Toward a Lake Ice Phenology Derived from VIIRS Data

    Sütterlin, Melanie; Duguay-Tetzlaff, Anke; Wunderle, Stefan


    this study is a physical mono-window (PMW) model based on the Radiative Transfer for the Television Infrared Observation Satellite Operational Vertical Sounder code (RTTOV). RTTOV, which is a fast radiative transfer model, can be used to estimate upward and downward atmospheric path radiance and atmospheric transmittance in the thermal infrared for a specific atmospheric profile. In this study, atmospheric profiles from ECMWF ERA-interim are utilized to run RTTOV and simulate top-of-atmosphere (TOA) brightness temperatures. We present the first retrievals of LSWT and ice features from corrected clear-sky channel I05 data of the VIIRS sensor. Together with VIS and NIR reflectance values, these first LSWT retrievals are used to derive ice-on/off dates for selected Swiss lakes by applying a threshold method. After successful validation based on in-situ measurements of Swiss lakes, the method can be utilized for global application.

  19. Interleukin-27 is differentially associated with HIV viral load and CD4+ T cell counts in therapy-naive HIV-mono-infected and HIV/HCV-co-infected Chinese.

    Lai He

    Full Text Available Human Immunodeficiency Virus (HIV infection and the resultant Acquired Immunodeficiency Syndrome (AIDS epidemic are major global health challenges; hepatitis C virus (HCV co-infection has made the HIV/AIDS epidemic even worse. Interleukin-27 (IL-27, a cytokine which inhibits HIV and HCV replication in vitro, associates with HIV infection and HIV/HCV co-infection in clinical settings. However, the impact of HIV and HCV viral loads on plasma IL-27 expression levels has not been well characterized. In this study, 155 antiretroviral therapy-naïve Chinese were recruited. Among them 80 were HIV- and HCV-negative healthy controls, 45 were HIV-mono-infected and 30 were HIV/HCV-co-infected. Plasma level HIV, HCV, IL-27 and CD4+ number were counted and their correlation, regression relationships were explored. We show that: plasma IL-27 level was significantly upregulated in HIV-mono-infected and HIV/HCV-co-infected Chinese; HIV viral load was negatively correlated with IL-27 titer in HIV-mono-infected subjects whereas the relationship was opposite in HIV/HCV-co-infected subjects; and the relationships between HIV viral loads, IL-27 titers and CD4+ T cell counts in the HIV mono-infection and HIV/HCV co-infection groups were dramatically different. Overall, our results suggest that IL-27 differs in treatment-naïve groups with HIV mono-infections and HIV/HCV co-infections, thereby providing critical information to be considered when caring and treating those with HIV mono-infection and HIV/HCV co-infection.

  20. Lake Michigan lake trout PCB model forecast post audit

    Scenario forecasts for total PCBs in Lake Michigan (LM) lake trout were conducted using the linked LM2-Toxics and LM Food Chain models, supported by a suite of additional LM models. Efforts were conducted under the Lake Michigan Mass Balance Study and the post audit represents th...

  1. Lake Erie Fish Community Data

    U.S. Geological Survey, Department of the Interior — Lake Erie Biological Station (LEBS), located in Sandusky, Ohio, is a field station of the USGS Great Lakes Science Center (GLSC). LEBS is the primary federal agency...

  2. Crescent Lake Wilderness Reference Sheet

    US Fish and Wildlife Service, Department of the Interior — Reference sheet includes information about Crescent Lake National Wildlife Refuge, and results of the public hearing for Crescent Lake Wilderness Proposal.

  3. Freshwater lake seabird surveys 2012

    US Fish and Wildlife Service, Department of the Interior — The Alaska Peninsula/Becharof NWR complex hosts Becharof Lake, the largest lake within a National Wildlife Refuge system. In addition to this distinction, Becharof...

  4. Great Lakes Environmental Database (GLENDA)

    U.S. Environmental Protection Agency — The Great Lakes Environmental Database (GLENDA) houses environmental data on a wide variety of constituents in water, biota, sediment, and air in the Great Lakes area.

  5. Functional microbiology of soda lakes

    Sorokin, D.Y.; Banciu, H.L.; Muyzer, G.


    Soda lakes represent unique permanently haloalkaline system. Despite the harsh conditions, they are inhabited by abundant, mostly prokaryotic, microbial communities. This review summarizes results of studies of main functional groups of the soda lake prokaryotes responsible for carbon, nitrogen and

  6. Effects of forest fragmentation on the mating system of a cool-temperate heterodichogamous tree Acer mono

    Satoshi Kikuchi


    Full Text Available Pollination is a key process for reproduction and gene flow in flowering plants. Anthropogenic habitat fragmentation, however, can disrupt plant–pollinator interactions, and may have a negative impact on the reproductive success and population viability of entomophilous plants. Heterodichogamous plants containing protandrous and protogynous individuals within a population may be susceptible to habitat fragmentation due to a lack of available mating partners. In this study, we investigated the effects of forest fragmentation on the mating system in the heterodichogamous plant Acer mono, a major constituent of cool-temperate deciduous forests in Japan. Microsatellite analysis was applied to 212 adult trees and 17 seed families from continuous and fragmented forests. Dispersal kernel modeling using the neighborhood model indicated that pollen dispersal of A. mono was highly fat-tailed. The estimated parameters of the model suggested that the siring success of a pollen donor increased approximately fivefold, with a 100 cm increase in its diameter at breast height (DBH, and that disassortative mating was five times more frequent than assortative mating. The mating system parameters of each mother tree, outcrossing rate (tm, biparental inbreeding (tm−ts, and paternity correlation (rpm varied among sites and conditions, depending on the local density of potential pollen donors. Whereas A. mono was effectively outcrossed (tm=0.901, tm−ts=0.052, and the number of effective sires was 1/rpm=14.93 in the continuous forest, clumped trees within the fragmented forest showed increased biparental inbreeding and reduced pollen pool genetic diversity (tm=0.959, tm−ts=0.245,1/rpm=1.742 as a result of localized mating combined with spatial genetic structures. In contrast, the isolated trees had a higher selfing rate, but the pollen pool diversity was maintained (tm=0.801, tm−ts=0.022, and 1/rpm=15.63 due to frequent long-distance pollination. These

  7. Microplastic pollution in lakes and lake shoreline sediments - A case study on Lake Bolsena and Lake Chiusi (central Italy).

    Fischer, Elke Kerstin; Paglialonga, Lisa; Czech, Elisa; Tamminga, Matthias


    Rivers and effluents have been identified as major pathways for microplastics of terrestrial sources. Moreover, lakes of different dimensions and even in remote locations contain microplastics in striking abundances. This study investigates concentrations of microplastic particles at two lakes in central Italy (Lake Bolsena, Lake Chiusi). A total number of six Manta Trawls have been carried out, two of them one day after heavy winds occurred on Lake Bolsena showing effects on particle distribution of fragments and fibers of varying size categories. Additionally, 36 sediment samples from lakeshores were analyzed for microplastic content. In the surface waters 2.68 to 3.36 particles/m(3) (Lake Chiusi) and 0.82 to 4.42 particles/m(3) (Lake Bolsena) were detected, respectively. Main differences between the lakes are attributed to lake characteristics such as surface and catchment area, depth and the presence of local wind patterns and tide range at Lake Bolsena. An event of heavy winds and moderate rainfall prior to one sampling led to an increase of concentrations at Lake Bolsena which is most probable related to lateral land-based and sewage effluent inputs. The abundances of microplastic particles in sediments vary from mean values of 112 (Lake Bolsena) to 234 particles/kg dry weight (Lake Chiusi). Lake Chiusi results reveal elevated fiber concentrations compared to those of Lake Bolsena what might be a result of higher organic content and a shift in grain size distribution towards the silt and clay fraction at the shallow and highly eutrophic Lake Chiusi. The distribution of particles along different beach levels revealed no significant differences.

  8. Regulation of TGF-β Superfamily Signaling by SMAD Mono-Ubiquitination

    Feng Xie


    Full Text Available TGF-β(transforming growth factor-β superfamily signaling mediators are important regulators of diverse physiological and pathological events. TGF-β signals are transduced by transmembrane type I and type II serine/threonine kinase receptors and their downstream effectors, the SMAD(drosophila mothers against decapentaplegic protein proteins. Numerous studies have already demonstrated crucial regulatory roles for modification of TGF-β pathway components by poly-ubiquitination. Recently, several studies also uncovered mono-ubiquitination of SMADs as a mechanism for SMAD activation or inactivation. Mono-ubiquitination and subsequent deubiquitination of SMAD proteins accordingly play important roles in the control of TGF-β superfamily signaling. This review highlights the major pathways regulated by SMAD mono-ubiquitination.

  9. Mono-X Versus Direct Searches: Simplified Models for Dark Matter at the LHC

    Liew, Seng Pei; Vichi, Alessandro; Zurek, Kathryn M


    We consider simplified models for dark matter (DM) at the LHC, focused on mono-Higgs, -Z, -W or -b produced in the final state. Our primary purpose is to study the LHC reach of a relatively complete set of simplified models for these final states, while comparing the reach of the mono-X DM search against direct searches for the mediating particle. We find that direct searches for the mediating particle, whether in di-jets, jets+MET, multi-b+MET, or di-boson+MET, are usually stronger. We draw attention to the cases that the mono-X search is strongest, which include regions of parameter space in inelastic DM, two Higgs doublet, and squark mediated production models with a compressed spectrum.

  10. Impact of temperature on performance of series and parallel connected mono-crystalline silicon solar cells

    Subhash Chander


    Full Text Available This paper presents a study on impact of temperature on the performance of series and parallel connected mono-crystalline silicon (mono-Si solar cell employing solar simulator. The experiment was carried out at constant light intensity 550 W/m2with cell temperature in the range 25–60 oC for single, series and parallel connected mono-Si solar cells. The performance parameters like open circuit voltage, maximum power, fill factor and efficiency are found to decrease with cell temperature while the short circuit current is observed to increase. The experimental results reveal that silicon solar cells connected in series and parallel combinations follow the Kirchhoff’s laws and the temperature has a significant effect on the performance parameters of solar cell.

  11. Second- and third-order nonlinear optical properties of unsubstituted and mono-substituted chalcones

    Abegão, Luis M. G.; Fonseca, Ruben D.; Santos, Francisco A.; Souza, Gabriela B.; Barreiros, André Luis B. S.; Barreiros, Marizeth L.; Alencar, M. A. R. C.; Mendonça, Cleber R.; Silva, Daniel L.; De Boni, Leonardo; Rodrigues, J. J.


    This work describes the second and third orders of nonlinear optics properties of unsubstituted chalcone (C15H12O) and mono-substituted chalcone (C16H14O2) in solution, using hyper-Rayleigh scattering and Z-Scan techniques to determine the first molecular hyperpolarizability (β) and the two-photon absorption (2PA) cross section respectively. β Values of 25.4 × 10-30 esu and 31.6 × 10-30 esu, for unsubstituted and mono-substituted chalcone, respectively, dissolved in methanol have been obtained. The highest values of 2PA cross-sections obtained were 9 GM and 14 GM for unsubstituted and mono-substituted chalcone, respectively. The experimental 2PA cross sections obtained for each chalcone are in good agreement with theoretical results.

  12. Matrix effects in applying mono- and polyclonal ELISA systems to the analysis of weathered oils in contaminated soil.

    Pollard, S J T; Farmer, J G; Knight, D M; Young, P J


    Commercial mono- and polyclonal enzyme-linked immunosorbent assay (ELISA) systems were applied to the on-site analysis of weathered hydrocarbon-contaminated soils at a former integrated steelworks. Comparisons were made between concentrations of solvent extractable matter (SEM) determined gravimetrically by Soxhlet (dichloromethane) extraction and those estimated immunologically by ELISA determination over a concentration range of 2000-330,000 mg SEM/kg soil dry weight. Both ELISA systems tinder-reported for the more weathered soil samples. Results suggest this is due to matrix effects in the sample rather than any inherent bias in the ELISA systems and it is concluded that, for weathered hydrocarbons typical of steelworks and coke production sites, the use of ELISA requires careful consideration as a field technique. Consideration of the target analyte relative to the composition of the hydrocarbon waste encountered appears critical.

  13. Modelling mono-digestion of grass silage in a 2-stage CSTR anaerobic digester using ADM1.

    Thamsiriroj, T; Murphy, J D


    This paper examines 174 days of experimental data and modelling of mono-digestion of grass silage in a two stage wet process with recirculation of liquor; the two vessels have an effective volume of 312 L each. The organic loading rate is initiated at 0.5 kg VS m(-3) d(-1) (first 74 days) and subsequently increased to 1 kg VS m(-3) d(-1). The experimental data was used to generate a mathematical model (ADM1) which was calibrated over the first 74 days of operation. Good accuracy with experimental data was found for the subsequent 100 days. Results of the model would suggest starting the process without recirculation and thus building up the solids content of the liquor. As the level of VFA increases, recirculation should be employed to control VFA. Recirculation also controls solids content and pH. Methane production was estimated at 88% of maximum theoretical production.

  14. A Lake Dream in Asia

    Yang Wei


    @@ When William Wordsworth,representative of Lake Poets wrote his Ode to Night ingale nearby the Lake District of England at the turn of the nine-teenth century,he never imagined a century later,a similar romantic lake dream has been created in China,Asia.

  15. Interesting Ziandao Lake


    LOCATED in Chun’an County, Zhejiang Province, Qiandao Lake (Lake of a Thousand Isles) is a state-level scenic spot and a bright pearl of the golden tourism line between Hangzhou’s West Lake and Anhui’s Huangshan Mountain. Last autumn, we went to Chun’an. It took only three to four hours by coach to travel from Hangzhou to Chun’an. Flanked by mountains on the west, the small county faces water on the east. A street goes across the county; it takes less than half an hour to walk from one end to the other. Small restaurants and shops line the western side of the road,

  16. Lake Morphometry for NHD Lakes in Great Lakes Region 4 HUC

    U.S. Environmental Protection Agency — Lake morphometry metrics are known to influence productivity in lakes and are important for building various types of ecological and environmental models of lentic...

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

    Giovanna Bosica


    Full Text Available 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.

  18. A study on synthesis and oxidation mechanism of mono-alkyl phosphate


    Oxidation of white phosphorus by peroxides to produce mono-alkyl phosphate in the alcoholic solution has been studied under non-and catalytic conditions. In this paper,the mechanism of the oxidation process was analyzed. The content of mono-alkyl phosphate in the product is affected by different types of alcoholic solution and peroxide solvent. The result shows the availability of the following order for the activity of the peroxide solvent and alcoholic solutions-tert-butyl hydroperoxide>(di) benzoyl perox...

  19. Extracting the complex optical conductivity of mono- and bilayer graphene by ellipsometry

    Chang, You-Chia; Liu, Chang-Hua; Liu, Che-Hung; Zhong, Zhaohui; Norris, Theodore B.


    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.

  20. Ultrasonication of pyrogenic microorganisms improves the detection of pyrogens in the Mono Mac 6 assay

    Moesby, Lise; Hansen, E W; Christensen, J D


    of the assay. The interleukin-6 inducing capacity of a broad spectrum of UV-killed and ultrasonicated microorganisms is examined in Mono Mac 6 cells. The interleukin-6 secretion is determined in a sandwich immunoassay (DELFIA). The Mono Mac 6 assay is able to detect UV-killed Bacillus subtilis, Staphylococcus...... aureus and Salmonella typhimurium, but neither Candida albicans nor Aspergillus niger. After ultrasonication of the microorganisms it is possible to detect C. albicans and A. niger. The interleukin-6 inducing ability of the examined microorganisms is in no case reduced after ultrasonic treatment. However...

  1. Perchlorate in Lake Water from an Operating Diamond Mine.

    Smith, Lianna J D; Ptacek, Carol J; Blowes, David W; Groza, Laura G; Moncur, Michael C


    Mining-related perchlorate [ClO4(-)] in the receiving environment was investigated at the operating open-pit and underground Diavik diamond mine, Northwest Territories, Canada. Samples were collected over four years and ClO4(-) was measured in various mine waters, the 560 km(2) ultraoligotrophic receiving lake, background lake water and snow distal from the mine. Groundwaters from the underground mine had variable ClO4(-) concentrations, up to 157 μg L(-1), and were typically an order of magnitude higher than concentrations in combined mine waters prior to treatment and discharge to the lake. Snow core samples had a mean ClO4(-) concentration of 0.021 μg L(-1) (n=16). Snow and lake water Cl(-)/ClO4(-) ratios suggest evapoconcentration was not an important process affecting lake ClO4(-) concentrations. The multiyear mean ClO4(-) concentrations in the lake were 0.30 μg L(-1) (n = 114) in open water and 0.24 μg L(-1) (n = 107) under ice, much below the Canadian drinking water guideline of 6 μg L(-1). Receiving lake concentrations of ClO4(-) generally decreased year over year and ClO4(-) was not likely [biogeo]chemically attenuated within the receiving lake. The discharge of treated mine water was shown to contribute mining-related ClO4(-) to the lake and the low concentrations after 12 years of mining were attributed to the large volume of the receiving lake.

  2. Modeling Antarctic subglacial lake filling and drainage cycles

    C. F. Dow


    Full Text Available The growth and drainage of active subglacial lakes in Antarctica has previously been inferred from analysis of ice surface altimetry data. We use a subglacial hydrology model applied to a synthetic Antarctic ice stream to determine internal controls on the filling and drainage of subglacial lakes and their impact on ice stream dynamics. Our model outputs suggest that the highly constricted subglacial environment of the ice stream, combined with relatively high rates of water flow funneled from large catchments, can combine to create a system exhibiting slow-moving pressure waves. Over a period of years, the accumulation of water in the ice stream onset region results in a buildup of pressure creating temporary channels, which then evacuate the excess water. This increased flux of water through the ice stream drives lake growth. As the water body builds up, it too steepens the hydraulic gradient and allows greater flux out of the overdeepened lake basin. Eventually this flux is large enough to create channels that cause the lake to drain. Due to the presence of the channels, the drainage of the lake causes high water pressures around 50 km downstream of the lake rather than immediately in the vicinity of the overdeepening. Following lake drainage, channels again shut down. Lake drainage depends on the internal hydrological development in the wider system and therefore does not directly correspond to a particular water volume or depth. This creates a highly temporally and spatially variable system, which is of interest for assessing the importance of subglacial lakes in ice stream hydrology and dynamics.

  3. Detecting acid precipitation impacts on lake water quality

    Loftis, Jim C.; Taylor, Charles H.


    The United States Environmental Protection Agency is planning to expand its long-term monitoring of lakes that are sensitive to acid deposition effects. Effective use of resources will require a careful definition of the statistical objectives of monitoring, a network design which balances spatial and temporal coverage, and a sound approach to data analysis. This study examines the monitoring objective of detecting trends in water quality for individual lakes and small groups of lakes. Appropriate methods of trend analysis are suggested, and the power of trend detection under seasonal (quarterly) sampling is compared to that of annual sampling. The effects of both temporal and spatial correlation on trend detection ability are described.

  4. Technologies for lake restoration

    Helmut KLAPPER


    Full Text Available Lakes are suffering from different stress factors and need to be restored using different approaches. The eutrophication remains as the main water quality management problem for inland waters: both lakes and reservoirs. The way to curb the degradation is to stop the nutrient sources and to accelerate the restoration with help of in-lake technologies. Especially lakes with a long retention time need (eco- technological help to decrease the nutrient content in the free water. The microbial and other organic matter from sewage and other autochthonous biomasses, causes oxygen depletion, which has many adverse effects. In less developed countries big reservoirs function as sewage treatment plants. Natural aeration solves problems only partly and many pollutants tend to accumulate in the sediments. The acidification by acid rain and by pyrite oxidation has to be controlled by acid neutralizing technologies. Addition of alkaline chemicals is useful only for soft waters, and technologies for (microbial alkalinization of very acidic hardwater mining lakes are in development. The corrective measures differ from those in use for eutrophication control. The salinization and water shortage mostly occurs if more water is used than available. L. Aral, L. Tschad, the Dead Sea or L. Nasser belong to waters with most severe environmental problems on a global scale. Their hydrologic regime needs to be evaluated. The inflow of salt water at the bottom of some mining lakes adds to stability of stratification, and thus accumulation of hydrogen sulphide in the monimolimnion of the meromictic lakes. Destratification, which is the most used technology, is only restricted applicable because of the dangerous concentrations of the byproducts of biological degradation. The contamination of lakes with hazardous substances from industry and agriculture require different restoration technologies, including subhydric isolation and storage, addition of nutrients for better self

  5. Lakes on Mars

    Cabrol, Nathalie A


    On Earth, lakes provide favorable environments for the development of life and its preservation as fossils. They are extremely sensitive to climate fluctuations and to conditions within their watersheds. As such, lakes are unique markers of the impact of environmental changes. Past and current missions have now demonstrated that water once flowed at the surface of Mars early in its history. Evidence of ancient ponding has been uncovered at scales ranging from a few kilometers to possibly that of the Arctic ocean. Whether life existed on Mars is still unknown; upcoming missions may find critic

  6. Reevaluation of lake trout and lake whitefish bioenergetics models

    Madenjian, Charles P.; Pothoven, Steve A.; Kao, Yu-Chun


    Using a corrected algorithm for balancing the energy budget, we reevaluated the Wisconsin bioenergetics model for lake trout (Salvelinus namaycush) in the laboratory and for lake whitefish (Coregonus clupeaformis) in the laboratory and in the field. For lake trout, results showed that the bioenergetics model slightly overestimated food consumption by the lake trout when they were fed low and intermediate rations, whereas the model predicted food consumption by lake trout fed ad libitum without any detectable bias. The slight bias in model predictions for lake trout on restricted rations may have been an artifact of the feeding schedule for these fish, and we would therefore recommend application of the Wisconsin lake trout bioenergetics model to lake trout populations in the field without any revisions to the model. Use of the Wisconsin bioenergetics model for coregonids resulted in overestimation of food consumption by lake whitefish both in the laboratory and in the field by between 20 and 30%, on average. This overestimation of food consumption was most likely due to overestimation of respiration rate. We therefore adjusted the respiration component of the bioenergetics model to obtain a good fit to the observed consumption in our laboratory tanks. The adjusted model predicted the consumption in the laboratory and the field without any detectable bias. Until a detailed lake whitefish respiration study can be conducted, we recommend application of our adjusted version of the Wisconsin generalized coregonid bioenergetics model to lake whitefish populations in the field.

  7. Ellsworth Subglacial Lake, West Antarctica: A review of its history and recent field campaigns

    Ross, N.; Siegert, M. J.; Rivera, A.; Bentley, M. J.; Blake, D.; Capper, L.; Clarke, R.; Cockell, C. S.; Corr, H. F. J.; Harris, W.; Hill, C.; Hindmarsh, R. C. A.; Hodgson, D. A.; King, E. C.; Lamb, H.; Maher, B.; Makinson, K.; Mowlem, M.; Parnell, J.; Pearce, D. A.; Priscu, J.; Smith, A. M.; Tait, A.; Tranter, M.; Wadham, J. L.; Whalley, W. B.; Woodward, J.

    Ellsworth Subglacial Lake, first observed in airborne radio echo sounding data acquired in 1978, is located within a long, deep subglacial trough within the Ellsworth Subglacial Highlands of West Antarctica. Geophysical surveys have characterized the lake, its subglacial catchment, and the thickness, structure, and flow of the overlying ice sheet. Covering 28.9 km2, Ellsworth Subglacial Lake is located below 2.9 to 3.3 km of ice at depths of -1361 to -1030 m. Seismic reflection data have shown the lake to be up to 156 m deep and underlain by unconsolidated sediments. Ice sheet flow over the lake is characterized by low velocities (2 m of sediment below the lake floor, (4) water circulation modeling suggesting a melting ice-water interface, and (5) coring that can target the deepest point of the lake floor away from marginal, localized sediment sources.

  8. Ciliated protozoa of two antarctic lakes: analysis by quantitative protargol staining and examination of artificial substrates

    Kepner, R. L. Jr; Wharton, R. A. Jr; Coats, D. W.; Wharton RA, J. r. (Principal Investigator)


    Planktonic and artificial substrate-associated ciliates have been identified in two perennially ice-covered antarctic lakes of the McMurdo Dry Valleys. Abundances estimated by quantitative protargol staining ranged from Vorticella. The taxonomic findings compare favorably with those of previous investigators; however four previously unreported genera were observed in both Lakes Fryxell and Hoare. The variability in the depth distributions of ciliates in Lake Fryxell is explained in terms of lake physicochemical properties and ciliate prey distributions, while factors related to temporal succession in the Lake Hoare assemblage remain unexplained. Local marine or temperate zone freshwater habitats are a more likely source than the surrounding dry valleys soils for present ciliate colonists in these lakes. Although the taxonomic uncertainties require further examination, our results suggest that ciliate populations in these antarctic lakes undergo significant fluctuations and are more diverse than was previously recognized.

  9. Biology and status of the shortnose cisco Coregonus reighardi Koelz in the Laurentian Great Lakes

    Webb, Shane A.; Todd, Thomas N.


    The shortnose cisco, Coregonus reighardi, a member of the endemic species assemblage of Coregoninae in the Laurentian Great Lakes, was commercially important until overfishing and competition pressures from induced planktivores extirpated the species in Lakes Michigan and Ontario. Spawning shortnose ciscoes have been collected from Lake Huron and Georgian Bay of Lake Huron since 1956, however, no individuals have been collected from these habitats since 1985. Shortnose ciscoes were not collected during surveys of the cisco fishery of Georgian Bay during the summer of 1992 and spring of 1993. The lack of captures in the last eight years coupled with captures of only lone individuals in the last 16 years suggests the species may be extinct in all of the Laurentian system. The life history traits examined for Lake Huron shortnose ciscoes were similar to the conditions recorded for Lake Michigan and Ontario shortnose ciscoes, although Lake Huron fish were smaller.

  10. Sedimentation influx and volcanic interactions in the Fuji Five Lakes: implications for paleoseismological records

    Lamair, Laura; Hubert-Ferrari, Aurélia; Yamamoto, Shinya; El Ouahabi, Meriam; Garrett, Ed; Shishikura, Masanobu; Schmidt, Sabine; Boes, Evelien; Obrochta, Stephen; Nakamura, Atsunori; Miyairi, Yosuke; Yokoyama, Yusuke; De Batist, Marc; Heyvaert, Vanessa M. A.


    The Fuji Fives Lakes are located at the foot of Mount Fuji volcano close to the triple junction, where the North American Plate, the Eurasian plate and the Philippine Sea Plate meet. These lakes are ideally situated to study Mount Fuji volcanism and the interaction between volcanism, changes in lake sedimentation rates and the ability of lakes to record paleoearthquakes. Here, we present newly acquired geological data of Lake Yamanaka and Lake Motosu, including seismic reflection profiles, gravity and piston cores. These two lakes and their respective watersheds were affected by several eruptions of Mount Fuji. Lake Yamanaka, a very shallow lake (max. depth 14 m), was heavily impacted by the scoria fall-out of the A.D. 1707 Hoei eruption of Mount Fuji. A detailed investigation of the effect of the Hoei eruption was conducted on short gravity cores, using high resolution XRD, C/N and 210Pb/137Cs analyses. The preliminary results suggest that the sedimentation rate of Lake Yamanaka drastically reduced after the Hoei eruption, followed by an increase until the present day. Similarly, lacustrine sedimentation in Lake Motosu (max. depth 122 m) was disturbed by Mount Fuji volcanism at a larger scale. The watershed of Lake Motosu was impacted by several lava flows and scoria cones. For example, the Omuro scoria cone reduced the catchment size of Lake Motosu and modified its physiography. The related scoria fall out covered an extensive part of the lake catchment and reduced terrigenous sedimentary influx to Lake Motosu. Within the deep basin of Lake Motosu, seismic reflection data shows two different periods that are distinguished by a major change in the dominant sedimentary processes. During the first period, sublacustrine landslides and turbidity currents were the dominant sedimentation processes. During the second one, the seismic stratigraphy evidences only deposition of numerous turbidites interrupting the hemipelagic sedimentation. Changes in sedimentary processes

  11. Final Results From the Circumarctic Lakes Observation Network (CALON) Project

    Hinkel, K. M.; Arp, C. D.; Eisner, W. R.; Frey, K. E.; Grosse, G.; Jones, B. M.; Kim, C.; Lenters, J. D.; Liu, H.; Townsend-Small, A.


    Since 2012, the physical and biogeochemical properties of ~60 lakes in northern Alaska have been investigated under CALON, a project to document landscape-scale variability of Arctic lakes in permafrost terrain. The network has ten nodes along two latitudinal transects extending inland 200 km from the Arctic Ocean. A meteorological station is deployed at each node and six representative lakes instrumented and continuously monitored, with winter and summer visits for synoptic assessment of lake conditions. Over the 4-year period, winter and summer climatology varied to create a rich range of lake responses over a short period. For example, winter 2012-13 was very cold with a thin snowpack producing thick ice across the region. Subsequent years had relatively warm winters, yet regionally variable snow resulted in differing gradients of ice thickness. Ice-out timing was unusually late in 2014 and unusually early in 2015. Lakes are typically well-mixed and largely isothermal, with minor thermal stratification occurring in deeper lakes during calm, sunny periods in summer. Lake water temperature records and morphometric data were used to estimate the ground thermal condition beneath 28 lakes. Application of a thermal equilibrium steady-state model suggests a talik penetrating the permafrost under many larger lakes, but lake geochemical data do not indicate a significant contribution of subpermafrost groundwater. Biogeochemical data reveal distinct spatial and seasonal variability in chlorophyll biomass, chromophoric dissolved organic carbon (CDOM), and major cations/anions. Generally, waters sampled beneath ice in April had distinctly higher concentrations of inorganic solutes and methane compared with August. Chlorophyll concentrations and CDOM absorption were higher in April, suggesting significant biological/biogeochemical activity under lake ice. Lakes are a positive source of methane in summer, and some also emit nitrous oxide and carbon dioxide. As part of the

  12. Molecular phylogenetic investigations of the Viviparidae (Gastropoda: Caenogastropoda) in the lakes of the Rift Valley area of Africa.

    Sengupta, Mita E; Kristensen, Thomas K; Madsen, Henry; Jørgensen, Aslak


    The freshwater gastropod family Viviparidae is nearly cosmopolitan, but absent from South America. On the African continent, two genera are recognized; the widespread Bellamya and the monotypic Neothauma, which is confined to Lake Tanganyika. Most of the African Bellamya species are confined to the major lakes of the Rift Valley area in Africa, i.e. Lake Albert, Lake Malawi, Lake Mweru, and Lake Victoria. The phylogenetic analyses of mitochondrial (COI and 16S) and nuclear (H3, 18S and 28S) DNA inferred three major lake-clades; i.e. Lake Victoria/Kyoga/Albert, Lake Malawi and Lake Mweru/Bangweulu. The endemic B. rubicunda from Lake Albert and B. unicolor from Lake Kyoga were inferred to be part of the Lake Victoria clade. Bellamya capillata as identified by shell characters was polyphyletic in gene trees. The monophyletic Bellamya species radiation in Lake Malawi was most nearly related to the Lake Victoria/Kyoga/Albert-clade. Taxa from the Zambian lakes, Mweru and Bangweulu, were inferred together and placed ancestral to the other lakes. Neothauma tanganyicense was inferred as the sister-group to the Zambian Bellamya. Within the lake-clades the endemic radiations show very low genetic diversities (0-4.1% in COI), suggesting much faster morphological divergence than molecular divergence. Alternatively, Bellamya in Africa constitutes only a few species with several sub-species or eco-phenotypic morphs. The African viviparids were inferred to be the sister-group to a clade comprising Asian species, and the relatively low genetic diversity between the clades (12.6-15.5% in COI) makes a recent Miocene dispersal event from Asia to Africa much more likely than an ancient Gondwana vicarience distribution.

  13. Subglacial lake drainage detected beneath the Greenland ice sheet.

    Palmer, Steven; McMillan, Malcolm; Morlighem, Mathieu


    The contribution of the Greenland ice sheet to sea-level rise has accelerated in recent decades. Subglacial lake drainage events can induce an ice sheet dynamic response--a process that has been observed in Antarctica, but not yet in Greenland, where the presence of subglacial lakes has only recently been discovered. Here we investigate the water flow paths from a subglacial lake, which drained beneath the Greenland ice sheet in 2011. Our observations suggest that the lake was fed by surface meltwater flowing down a nearby moulin, and that the draining water reached the ice margin via a subglacial tunnel. Interferometric synthetic aperture radar-derived measurements of ice surface motion acquired in 1995 suggest that a similar event may have occurred 16 years earlier, and we propose that, as the climate warms, increasing volumes of surface meltwater routed to the bed will cause such events to become more common in the future.

  14. Subglacial lake drainage detected beneath the Greenland ice sheet

    Palmer, Steven; McMillan, Malcolm; Morlighem, Mathieu


    The contribution of the Greenland ice sheet to sea-level rise has accelerated in recent decades. Subglacial lake drainage events can induce an ice sheet dynamic response—a process that has been observed in Antarctica, but not yet in Greenland, where the presence of subglacial lakes has only recently been discovered. Here we investigate the water flow paths from a subglacial lake, which drained beneath the Greenland ice sheet in 2011. Our observations suggest that the lake was fed by surface meltwater flowing down a nearby moulin, and that the draining water reached the ice margin via a subglacial tunnel. Interferometric synthetic aperture radar-derived measurements of ice surface motion acquired in 1995 suggest that a similar event may have occurred 16 years earlier, and we propose that, as the climate warms, increasing volumes of surface meltwater routed to the bed will cause such events to become more common in the future. PMID:26450175

  15. A Mass balance mercury budget for a mine-dominated lake: Clear Lake, California

    Suchanek, T.H.; Cooke, J.; Keller, K.; Jorgensen, S.; Richerson, P.J.; Eagles-Smith, C. A.; Harner, E.J.; Adam, D.P.


    The Sulphur Bank Mercury Mine (SBMM), active intermittently from 1873-1957 and now a USEPA Superfund site, was previously estimated to have contributed at least 100 metric tons (105 kg) of mercury (Hg) into the Clear Lake aquatic ecosystem. We have confirmed this minimum estimate. To better quantify the contribution of the mine in relation to other sources of Hg loading into Clear Lake and provide data that might help reduce that loading, we analyzed Inputs and Outputs of Hg to Clear Lake and Storage of Hg in lakebed sediments using a mass balance approach. We evaluated Inputs from (1) wet and dry atmospheric deposition from both global/regional and local sources, (2) watershed tributaries, (3) groundwater inflows, (4) lakebed springs and (5) the mine. Outputs were quantified from (1) efflux (volatilization) of Hg from the lake surface to the atmosphere, (2) municipal and agricultural water diversions, (3) losses from out-flowing drainage of Cache Creek that feeds into the California Central Valley and (4) biotic Hg removal by humans and wildlife. Storage estimates include (1) sediment burial from historic and prehistoric periods (over the past 150-3,000 years) from sediment cores to ca. 2.5m depth dated using dichloro diphenyl dichloroethane (DDD), 210Pb and 14C and (2) recent Hg deposition in surficial sediments. Surficial sediments collected in October 2003 (11 years after mine site remediation) indicate no reduction (but a possible increase) in sediment Hg concentrations over that time and suggest that remediation has not significantly reduced overall Hg loading to the lake. Currently, the mine is believed to contribute ca. 322-331 kg of Hg annually to Clear Lake, which represents ca. 86-99% of the total Hg loading to the lake. We estimate that natural sedimentation would cover the existing contaminated sediments within ca. 150-300 years. ?? 2008 Springer Science+Business Media B.V.

  16. Exploration of Microbial Diversity and Community Structure of Lonar Lake: The Only Hypersaline Meteorite Crater Lake within Basalt Rock.

    Paul, Dhiraj; Kumbhare, Shreyas V; Mhatre, Snehit S; Chowdhury, Somak P; Shetty, Sudarshan A; Marathe, Nachiket P; Bhute, Shrikant; Shouche, Yogesh S


    Lonar Lake is a hypersaline and hyperalkaline soda lake and the only meteorite impact crater in the world situated in basalt rocks. Although culture-dependent studies have been reported, a comprehensive understanding of microbial community composition and structure in Lonar Lake remains elusive. In the present study, microbial community structure associated with Lonar Lake sediment and water samples was investigated using high-throughput sequencing. Microbial diversity analysis revealed the existence of diverse, yet largely consistent communities. Proteobacteria (30%), Actinobacteria (24%), Firmicutes (11%), and Cyanobacteria (5%) predominated in the sequencing survey, whereas Bacteroidetes (1.12%), BD1-5 (0.5%), Nitrospirae (0.41%), and Verrucomicrobia (0.28%) were detected in relatively minor abundances in the Lonar Lake ecosystem. Within the Proteobacteria phylum, the Gammaproteobacteria represented the most abundantly detected class (21-47%) within sediment samples, but only a minor population in the water samples. Proteobacteria and Firmicutes were found at significantly higher abundance (p ≥ 0.05) in sediment samples, whereas members of Actinobacteria, Candidate division TM7 and Cyanobacteria (p ≥ 0.05) were significantly abundant in water samples. Compared to the microbial communities of other hypersaline soda lakes, those of Lonar Lake formed a distinct cluster, suggesting a different microbial community composition and structure. Here we report for the first time, the difference in composition of indigenous microbial communities between the sediment and water samples of Lonar Lake. An improved census of microbial community structure in this Lake ecosystem provides a foundation for exploring microbial biogeochemical cycling and microbial function in hypersaline lake environments.

  17. Exploration of microbial diversity and community structure of Lonar Lake: the only hypersaline meteorite crater lake within basalt rock

    Dhiraj ePaul


    Full Text Available Lonar Lake is a hypersaline and hyperalkaline soda lake and the only meteorite impact crater in the world created in the basalt rocks. Although culture-dependent studies have been reported, the comprehensive understanding of microbial community composition and structure of Lonar Lake remain obscure. In the present study, microbial community structure associated with Lonar Lake sediment and water samples was investigated using high throughput sequencing. Microbial diversity analysis revealed the existence of diverse, yet near consistent community composition. The predominance of bacterial phyla Proteobacteria (30% followed by Actinobacteria (24%, Firmicutes (11% and Cyanobacteria (5% was observed. Bacterial phylum Bacteroidetes (1.12%, BD1-5 (0.5%, Nitrospirae (0.41% and Verrucomicrobia (0.28% were detected as relatively minor populations in Lonar Lake ecosystem. Within Proteobacteria, Gammaproteobacteria represented the most abundant population (21-47% among all the sediments and as a minor population in water samples. Bacterial members Proteobacteria and Firmicutes were present significantly higher (p≥0.05 in sediment samples, whereas members of Actinobacteria, Candidate_division_TM7 and Cyanobacteria (p≥0.05 were significantly abundant in water samples. It was noted that compared to other hypersaline soda lakes, Lonar Lake samples formed one distinct cluster, suggesting a different microbial community composition and structure. The present study reports for the first time the different composition of indigenous microbial communities between the sediment and water samples of Lonar Lake. Having better insight of community structure of this Lake ecosystem could be useful in understanding the microbial role in the geochemical cycle for future functional exploration of the unique hypersaline Lonar Lake.

  18. Non-destructive elemental analysis of large meteorite samples by prompt gamma-ray neutron activation analysis with the internal mono-standard method.

    Latif, Sk A; Oura, Y; Ebihara, M; Nakahara, H


    Prompt gamma-ray neutron activation analysis (PGNAA) using the internal mono-standard method was tested for its applicability to analyzing large solid samples including irregularly shaped meteorite samples. For evaluating the accuracy and precision of the method, large quantities of the Geological Survey of Japan standardized rock powders (JB-1a, JG-1a, and JP-1) were analyzed and 12 elements (B, Na, Mg, Al, Cl, K, Ca, Ti, Mn, Fe, Sm, and Gd) were determined by using Si as an internal standard element. Analytical results were mostly in agreement with literature values within 10 %. The precision of the method was also shown to be within 10 % (1σ) for most of these elements. The analytical procedure was then applied to four stony meteorites (Allende, Kimble County, Leedey, Lake Labyrinth) and four iron meteorites (Canyon Diablo, Toluca (Mexico), Toluca (Xiquipilco), Squaw Creek) consisting of large chunks or single slabs. For stony meteorites, major elements (Mg, Al, Si, S, Ca, and Ni), minor elements (Na and Mn) and trace element (B, Cl, K, Ti, Co, and Sm) were determined with adequate accuracy. For iron meteorites, results for the Co and Ni mass fractions determined are all consistent with corresponding literature values. After the analysis, it was confirmed that the residual radioactivity remaining in the sample after PGNAA was very low and decreased down to the background level. This study shows that PGNAA with the internal mono-standard method is highly practical for determining the elemental composition of large, irregularly shaped solid samples including meteorites.

  19. Chromosome engineering: generation of mono- and dicentric isochromosomes in a somatic cell hybrid system.

    Higgins, A W; Schueler, M G; Willard, H F


    The most common isochromosome found in humans involves the long arm of the X, i(Xq), and is associated with a subset of Turner syndrome cases. To study the formation and behavior of isochromosomes in a more tractable experimental system, we have developed a somatic cell hybrid model system that allows for the selection of mono- or dicentric isochromosomes involving the short arm of the X, i(Xp). Simultaneous positive and negative counterselection of a mouse/human somatic cell hybrid containing a human X chromosome, selecting for retention of the UBE1 locus in Xp but against the HPRT locus in Xq, results in a variety of abnormalities of the X chromosome involving deletions of Xq. We have generated 70 such "Pushmi-Pullyu" hybrids derived from seven independent X chromosomes. Cytogenetic analysis of these hybrids using fluorescence in situ hybridization showed i(Xp) chromosomes in approximately 19% of the hybrids. Southern blot and polymerase chain reaction analyses of the Pushmi-Pullyu hybrids revealed a distribution of breakpoints along Xq. The distance between the centromeres of the dicentric i(Xp)s generated ranged from approximately 2 Mb to approximately 20 Mb. To examine centromeric activity in these dicentric i(Xp)s, we used indirect immunofluorescence with antibodies to centromere protein E (CENP-E). CENP-E was detected at only one of the centromeres of a dicentric i(Xp) with approximately 2-3 Mb of Xq DNA. In contrast, CENP-E was detected at both centromeres of a dicentric i(Xp) with approximately 14 Mb of Xq DNA. Two other dicentric i(Xp) chromosomes were heterogeneous with respect to centromeric activity, suggesting that centromeric activity and chromosome stability of dicentric chromosomes may be more complicated than previously thought. The Pushmi-Pullyu model system presented in this study may provide a tool for examining the structure and function of mammalian centromeres.

  20. Europe's Neogene and Quaternary lake gastropod diversity - a statistical approach

    Neubauer, Thomas A.; Georgopoulou, Elisavet; Harzhauser, Mathias; Mandic, Oleg; Kroh, Andreas


    During the Neogene Europe's geodynamic history gave rise to several long-lived lakes with conspicuous endemic radiations. However, such lacustrine systems are rare today as well as in the past compared to the enormous numbers of "normal" lakes. Most extant European lakes are mainly results of the Ice Ages and are due to their (geologically) temporary nature largely confined to the Pleistocene-Holocene. As glacial lakes are also geographically restricted to glacial regions (and their catchment areas) their preservation potential is fairly low. Also deposits of streams, springs, and groundwater, which today are inhabited by species-rich gastropod assemblages, are rarely preserved. Thus, the pre-Quaternary lacustrine record is biased towards long-lived systems, such as the Late Miocene Lake Pannon, the Early to Middle Miocene Dinaride Lake System, the Middle Miocene Lake Steinheim and several others. All these systems have been studied for more than 150 years concerning their mollusk inventories and the taxonomic literature is formidable. However, apart from few general overviews precise studies on the γ-diversities of the post-Oligocene European lake systems and the shifting biodiversity in European freshwater systems through space and time are entirely missing. Even for the modern faunas, literature on large-scale freshwater gastropod diversity in extant lakes is scarce and lacks a statistical approach. Our preliminary data suggest fundamental differences between modern and pre-Pleistocene freshwater biogeography in central Europe. A rather homogenous central European Pleistocene and Holocene lake fauna is contrasted by considerable provincialism during the early Middle Miocene. Aside from the ancient Dessaretes lakes of the Balkan Peninsula, Holocene lake faunas are dominated by planorbids and lymnaeids in species numbers. This composition differs considerably from many Miocene and Pliocene lake faunas, which comprise pyrgulid-, hydrobiid-, viviparid-, melanopsid

  1. Lake whitefish diet, condition, and energy density in Lake Champlain and the lower four Great Lakes following dreissenid invasions

    Herbst, Seth J.; Marsden, J. Ellen; Lantry, Brian F.


    Lake Whitefish Coregonus clupeaformis support some of the most valuable commercial freshwater fisheries in North America. Recent growth and condition decreases in Lake Whitefish populations in the Great Lakes have been attributed to the invasion of the dreissenid mussels, zebra mussels Dreissena polymorpha and quagga mussels D. bugensis, and the subsequent collapse of the amphipod, Diporeia, a once-abundant high energy prey source. Since 1993, Lake Champlain has also experienced the invasion and proliferation of zebra mussels, but in contrast to the Great Lakes, Diporeia were not historically abundant. We compared the diet, condition, and energy density of Lake Whitefish from Lake Champlain after the dreissenid mussel invasion to values for those of Lake Whitefish from Lakes Michigan, Huron, Erie, and Ontario. Lake Whitefish were collected using gill nets and bottom trawls, and their diets were quantified seasonally. Condition was estimated using Fulton's condition factor (K) and by determining energy density. In contrast to Lake Whitefish from some of the Great Lakes, those from Lake Champlain Lake Whitefish did not show a dietary shift towards dreissenid mussels, but instead fed primarily on fish eggs in spring, Mysis diluviana in summer, and gastropods and sphaeriids in fall and winter. Along with these dietary differences, the condition and energy density of Lake Whitefish from Lake Champlain were high compared with those of Lake Whitefish from Lakes Michigan, Huron, and Ontario after the dreissenid invasion, and were similar to Lake Whitefish from Lake Erie; fish from Lakes Michigan, Huron, and Ontario consumed dreissenids, whereas fish from Lake Erie did not. Our comparisons of Lake Whitefish populations in Lake Champlain to those in the Great Lakes indicate that diet and condition of Lake Champlain Lake Whitefish were not negatively affected by the dreissenid mussel invasion.

  2. Influence of precipitation, landscape and hydrogeomorphic lake features on pelagic allochthonous indicators in two connected ultraoligotrophic lakes of North Patagonia

    Queimalinos, Claudia, E-mail: [Laboratorio de Fotobiologia, Instituto de Investigaciones en Biodiversidad y Medio Ambiente (INIBIOMA, UNComahue-CONICET), Quintral 1250, R8400FRF Bariloche, Rio Negro (Argentina); Reissig, Mariana; Dieguez, Maria del Carmen [Laboratorio de Fotobiologia, Instituto de Investigaciones en Biodiversidad y Medio Ambiente (INIBIOMA, UNComahue-CONICET), Quintral 1250, R8400FRF Bariloche, Rio Negro (Argentina); Arcagni, Marina; Ribeiro Guevara, Sergio [Laboratorio de Analisis por Activacion Neutronica (LAAN), Centro Atomico Bariloche, Comision Nacional de Energia Atomica, Av. Bustillo 9500, R8402AGP Bariloche, Rio Negro (Argentina); Campbell, Linda [School of Environmental Studies, Saint Mary' s University, 923 Robie Street, Halifax, Nova Scotia, Canada B3H-3C3 (Canada); Soto Cardenas, Carolina [Laboratorio de Fotobiologia, Instituto de Investigaciones en Biodiversidad y Medio Ambiente (INIBIOMA, UNComahue-CONICET), Quintral 1250, R8400FRF Bariloche, Rio Negro (Argentina); Rapacioli, Raul [Facultad de Ingenieria, Universidad Nacional del Comahue, Buenos Aires1400, Q8300IBX Neuquen (Argentina); and others


    We investigated the terrestrial influence on two chained deep ultraoligotrophic lakes of North Patagonia (Argentina) through the seasonal analysis of two pelagic allochthonous indicators: i) water color, as a proxy of allochthonous dissolved organic matter in lakes; and ii) the color to chlorophyll a ratio (Color:Chla), as an indicator of the relationship between allochthonous and autochthonous carbon pools. We also evaluated the potential transfer pathways of the allochthonous dissolved organic matter into the pelagic food webs of these deep lakes, including the natural zooplankton {delta}{sup 13}C in the analysis. The dynamics of the allochthonous indicators were related to the precipitation regime, water level fluctuations, and hydrogeomorphic and catchment features of lakes Moreno East and Moreno West. The water color (absorbance at 440 nm) was extremely low (< 0.28 m{sup -1}) in both lakes regardless of the season. However, precipitation and snowmelt regimes drove the increase and decrease of water color, respectively. A significant positive relationship between the zooplankton bulk {delta}{sup 13}C with the water color would suggest an input of allochthonous organic carbon into the pelagic consumers. The incorporation of the dissolved allochthonous material into higher trophic levels is likely favored by the bacterivorous behavior of planktonic organisms, mixotrophic flagellates and ciliates, which dominate the pelagic food webs of these Patagonian lakes. Morphometric aspects, mainly the higher water residence time, led to lower values of allochthony in Moreno East compared to Moreno West, probably accentuated by its upper position in the lake chain. Overall, our results suggest that these allochthonous signals can bring insight into the magnitude of the interaction between terrestrial environments and lake ecosystems, even in extremely clear and ultraoligotrophic systems, such as the Andean Patagonian lakes. - Highlights: Black-Right-Pointing-Pointer Pelagic

  3. Composition and predicted functional ecology of mussel-associated bacteria in Indonesian marine lakes.

    Cleary, Daniel F R; Becking, Leontine E; Polónia, Ana R M; Freitas, Rossana M; Gomes, Newton C M


    In the present study, we sampled bacterial communities associated with mussels inhabiting two distinct coastal marine ecosystems in Kalimantan, Indonesia, namely, marine lakes and coastal mangroves. We used 16S rRNA gene pyrosequencing and predicted metagenomic analysis to compare microbial composition and function. Marine lakes are small landlocked bodies of seawater isolated to varying degrees from the open sea environment. They contain numerous endemic taxa and represent natural laboratories of speciation. Our primary goals were to (1) use BLAST search to identify closely related organisms to dominant bacterial OTUs in our mussel dataset and (2) to compare bacterial communities and enrichment in the predicted bacterial metagenome among lakes. Our sequencing effort yielded 3553 OTUs belonging to 44 phyla, 99 classes and 121 orders. Mussels in the largest marine lake (Kakaban) and the coastal mangrove habitat were dominated by bacteria belonging to the phylum Proteobacteria whereas smaller lakes, located on the island of Maratua, were dominated by bacteria belonging to the phyla Firmicutes and Tenericutes. The single most abundant OTU overall was assigned to the genus Mycoplasma. There were several significant differences among locations with respect to metabolic pathways. These included enrichment of xenobiotic biodegradation pathways in the largest marine lake and coastal mangrove. These locations were also the most enriched with respect to nitrogen metabolism. The presence of genes related to isoquinoline alkaloids, polyketides, hydrolases, mono and dioxygenases in the predicted analysis of functional pathways is an indication that the bacterial communities of Brachidontes mussels may be potentially important sources of new marine medicines and enzymes of industrial interest. Future work should focus on measuring how mussel microbial communities influence nutrient dynamics within the marine lake environment and isolating microbes with potential biotechnological

  4. Jurassic Lake T'oo'dichi': a large alkaline, saline lake, Morrison Formation, eastern Colorado Plateau

    Turner, C.E.; Fishman, N.S.


    Recognition of alkaline, saline-lake deposits in the Morrison Formation significantly alters interpretations of depositional environments of this formation, and it also has important implications for paleoclimatic interpretation. Late Jurassic climate was apparently much more arid than had previously been thought. In fact, sedimentologic evidence suggests that the lake basin was typically dry for extended periods and enjoyed only brief wet intervals. This conclusion has important consequences for environmental interpretation of the habitat that was favorable for large herbivorous dinosaurs, which thrived in the Late Jurassic. -from Authors

  5. Lake transparency: a window into decadal variations in dissolved organic carbon concentrations in Lakes of Acadia National Park, Maine

    Roesler, Collin S.; Culbertson, Charles W.


    A forty year time series of Secchi depth observations from approximately 25 lakes in Acadia National Park, Maine, USA, evidences large variations in transparency between lakes but relatively little seasonal cycle within lakes. However, there are coherent patterns over the time series, suggesting large scale processes are responsible. It has been suggested that variations in colored dissolved organic matter (CDOM) are primarily responsible for the variations in transparency, both between lakes and over time and further that CDOM is a robust optical proxy for dissolved organic carbon (DOC). Here we present a forward model of Secchi depth as a function of DOC based upon first principles and bio-optical relationships. Inverting the model to estimate DOC concentration from Secchi depth observations compared well with the measured DOC concentrations collected since 1995 (RMS error chemistry and watershed characteristics, including land cover and land use.

  6. Poet Lake Crystal Approval

    This September 19, 2016 letter from EPA approves the petition from Poet Biorefining-Lake Crystal, regarding non-grandfathered ethanol produced through a dry mill process, qualifying under the Clean Air Act for renewable fuel (D-code 6) RINs under the RFS

  7. in lake chamo, ethiopia


    zooplankton until they move to the littoral regions and start feeding .... Fish collected during the spawning season (i.e.,. March-June .... females, but sampling in the estuary downstream ... same size could be first-time spawners in Lake. Chamo ...

  8. Reclaiming the lake

    Rasmussen, Mattias Borg


    of individual rights that move well beyond the site of conflict. It is therefore argued that the actions to reclaim Lake Conococha were not only a battle for natural resources and clean water, but more fundamentally an attempt to repossess a citizenship that may be constitutionally secured but all too oft en...

  9. Lake Ontario: Nearshore Variability

    We conducted a high-resolution survey with towed electronic instrumentation along the Lake Ontario nearshore (720 km) at a 20 meter contour. The survey was conducted September 6-10, 2008 with a shorter 300 km survey conducted August 14-15 for comparing of temporal variability. ...

  10. 40 CFR 721.1950 - 2-Butenedioic acid (Z), mono(2-((1-oxopropenyloxy)ethyl) ester .


    ...-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...

  11. Polyurethane triblock copolymers with mono-disperse hard segments. Influence of the hard segment length on thermal and thermomechanical properties

    Arun, Araichimani; Baack, Kasper K.J.; Gaymans, Reinoud J.


    Polyurethane triblock copolymers were synthesized by reacting 4,4-methylenebis(phenyl isocyanate) (MDI)-endcapped poly(tetramethylene oxide) (PTMO) with mono-amine-amide (MMA) units. Four different MMA units were used, i.e. no-amide (6m), mono-amide (6B), di-amide (6T6m) and tri-amide (6T6B), based

  12. Reconciling the opposing effects of warming on phytoplankton biomass in 188 large lakes.

    Kraemer, Benjamin M; Mehner, Thomas; Adrian, Rita


    Lake ecosystems are deeply integrated into local and regional economies through recreation, tourism, and as sources of food and drinking water. Shifts in lake phytoplankton biomass, which are mediated by climate warming will alter these benefits with potential cascading effects on human well-being. The metabolic theory of ecology suggests that warming reduces lake phytoplankton biomass as basal metabolic costs increase, but this hypothesis has not been tested at the global scale. We use satellite-based estimates of lake surface temperature (LST) and lake surface chlorophyll-a concentration (chl-a; as a proxy for phytoplankton biomass) in 188 of the world's largest lakes from 2002-2016 to test for interannual associations between chl-a and LST. In contrast to predictions from metabolic ecology, we found that LST and chl-a were positively correlated in 46% of lakes (p < 0.05). The associations between LST and chl-a depended on lake trophic state; warming tended to increase chl-a in phytoplankton-rich lakes and decrease chl-a in phytoplankton-poor lakes. We attribute the opposing responses of chl-a to LST to the effects of temperature on trophic interactions, and the availability of resources to phytoplankton. These patterns provide insights into how climate warming alters lake ecosystems on which millions of people depend for their livelihoods.

  13. Groundwater contamination by microcystin from toxic cyanobacteria blooms in Lake Chaohu, China.

    Yang, Zhen; Kong, Fanxiang; Zhang, Min


    Lake Chaohu is a eutrophic lake that experiences massive cyanobacterial blooms. The high concentrations of microcystin observed in this lake are the result of the bloom's high proportion of toxic cyanobacteria strains. Groundwater is the important source of water for drinking, washing, and irrigation in the watershed of Lake Chaohu. This study examines the space-time distribution of microcystins and related environmental factors in wells near Lake Chaohu. All collected groundwater samples from the Lake Chaohu region had detectable concentrations of microcystins. The highest concentration of microcystins, 1.07 μg L(-1), occurred in a well hundreds of meters from the western coast of the lake in September. The distance from the lake shore to the well was significantly and positively correlated with the microcystin concentration in the groundwater. Moreover, a correlation analysis shows that the microcystin concentration in the groundwater was positively correlated with the total dissolved phosphorus (TDP) and microcystin concentration of the nearby lake water. Therefore, the microcystin in the groundwater likely originates from penetration by nearby lake water. Our results suggest that the groundwater near Lake Chaohu poses a significant health risk for the local residents when used for drinking water.

  14. Climate-induced changes in lake ecosystem structure inferred from coupled neo- and paleoecological approaches.

    Saros, Jasmine E; Stone, Jeffery R; Pederson, Gregory T; Slemmons, Krista E H; Spanbauer, Trisha; Schliep, Anna; Cahl, Douglas; Williamson, Craig E; Engstrom, Daniel R


    Over the 20th century, surface water temperatures have increased in many lake ecosystems around the world, but long-term trends in the vertical thermal structure of lakes remain unclear, despite the strong control that thermal stratification exerts on the biological response of lakes to climate change. Here we used both neo- and paleoecological approaches to develop a fossil-based inference model for lake mixing depths and thereby refine understanding of lake thermal structure change. We focused on three common planktonic diatom taxa, the distributions of which previous research suggests might be affected by mixing depth. Comparative lake surveys and growth rate experiments revealed that these species respond to lake thermal structure when nitrogen is sufficient, with species optima ranging from shallower to deeper mixing depths. The diatom-based mixing depth model was applied to sedimentary diatom profiles extending back to 1750 AD in two lakes with moderate nitrate concentrations but differing climate settings. Thermal reconstructions were consistent with expected changes, with shallower mixing depths inferred for an alpine lake where treeline has advanced, and deeper mixing depths inferred for a boreal lake where wind strength has increased. The inference model developed here provides a new tool to expand and refine understanding of climate-induced changes in lake ecosystems.

  15. Cytological Findings Suggesting Sexuality in Phytomonas davidi (Protozoa: Kinetoplastida

    Maria Auxiliadora de Sousa


    Full Text Available On few occasions, Phytomonas davidi (McGhee & Postell isolate cultures in LIT (liver infusion-tryptose medium around 27oC presented, as seen in Giemsa-stained smears, a set of peculiar morphological features, among them being noticeable the pairs of apposed cells attached by their posterior ends, where occurred a stained line and/or a dilatation, usually bulb-like in shape; sometimes this dilatation could occupy one of the cells or hold both together. In some pairs, the nucleus of each parasite seemed migrating towards the other, entering into such dilatation; in others, both nuclei were inside it, sometimes in close proximity or seeming fused; peculiar chromatin arrangements involving both nuclei were occasionally observed. Several mono or binucleate round forms bearing one or two flagella, as well as flagellate slender cells without nucleus were concomitantly seen there. In some instances, an intriguing small stained body occurred beside a single large nucleus, either in pairs presenting the bulb-like structure or in round cells. These cytological findings seemed steps of a dynamic process suggesting sexuality, since in several of them nuclear interactions following fusion of two parasites appeared to occur

  16. [Ecological compensation standard in Dongting Lake region of returning cropland to lake based on emergy analysis].

    Mao, De-Hua; Hu, Guang-Wei; Liu, Hui-Jie; Li, Zheng-Zui; Li, Zhi-Long; Tan, Zi-Fang


    The annual emergy and currency value of the main ecological service value of returning cropland to lake in Dongting Lake region from 1999 to 2010 was calculated based on emergy analysis. The calculation method of ecological compensation standard was established by calculating annual total emergy of ecological service function increment since the starting year of returning cropland to lake, and the annual ecological compensation standard and compensation area were analyzed from 1999 to 2010. The results indicated that ecological compensation standard from 1999 to 2010 was 40.31-86.48 yuan x m(-2) with the mean of 57.33 yuan x m(-2). The ecological compensation standard presented an increase trend year by year due to the effect of eco-recovery of returning cropland to lake. The ecological compensation standard in the research area presented a swift and steady growth trend after 2005 mainly due to the intensive economy development of Hunan Province, suggesting the value of natural ecological resources would increase along with the development of society and economy. Appling the emergy analysis to research the ecological compensation standard could reveal the dynamics of annual ecological compensation standard, solve the abutment problem of matter flow, energy flow and economic flow, and overcome the subjective and arbitrary of environment economic methods. The empirical research of ecological compensation standard in Dongting Lake region showed that the emergy analysis was feasible and advanced.

  17. Lake Levels since about 40,000 Years Ago at Lake Chalco, near Mexico City

    Caballero, Margarita; Guerrero, Beatriz Ortega


    Diatoms, magnetic susceptibility, organic content, and 14C ages of sediments from a 26-m core suggest that Lake Chalco, in the southern part of the basin of Mexico, went through a series of major fluctuations during the late Pleistocene and the Holocene. Before ca. 39,000 14C yr B.P. the lake was very deep (about 8-10 m), alkaline, and saline. It then became shallow (Chalco deepened to about 4-5 m about the time of a major eruption of nearby Popocatepetl volcano ca. 22,000 yr B.P. The lake remained relatively deep and fresh until ca. 18,500 yr B.P., when lower levels and alternating acidic to freshwater conditions were established. After 14,500 yr B.P. lake level rose slightly, but by ca. 10,000 yr B.P. Chalco became very shallow (Chalco became a fresh to slightly alkaline shallow lake a few meters deep.

  18. Directly dated MIS 3 lake-level record from Lake Manix, Mojave Desert, California, USA

    Reheis, Marith; Miller, David M.; McGeehin, John P.; Redwine, Joanna R.; Oviatt, Charles G.; Bright, Jordon E.


    An outcrop-based lake-level curve, constrained by ~ 70 calibrated 14C ages on Anodonta shells, indicates at least 8 highstands between 45 and 25 cal ka BP within 10 m of the 543-m upper threshold of Lake Manix in the Mojave Desert of southern California. Correlations of Manix highstands with ice, marine, and speleothem records suggest that at least the youngest three highstands coincide with Dansgaard–Oeschger (D–O) stadials and Heinrich events 3 and 4. The lake-level record is consistent with results from speleothem studies in the Southwest that indicate cool wet conditions during D–O stadials. Notably, highstands between 43 and 25 ka apparently occurred at times of generally low levels of pluvial lakes farther north as interpreted from core-based proxies. Mojave lakes may have been supported by tropical moisture sources during oxygen-isotope stage 3, perhaps controlled by southerly deflection of Pacific storm tracks due to weakening of the sea-surface temperature gradient in response to North Atlantic climate perturbations.

  19. A model for landscape development in terms of shoreline displacement, sediment dynamics, lake formation, and lake choke-up processes

    Brydsten, Lars [Umeaa University, Dept. of Ecology and Environmental Science (Sweden)


    This project expands on the study 'A mathematical model for lake ontogeny in terms of filling with sediments and macrophyte vegetation' published in SKB TR-04-09. As the title suggests, this older model focuses on lakes (existing and future lakes). This newer study extends the model to examine progress of terrestrial objects such as mires or arable land. Furthermore, this newer model could simulate progress of the areas close to the objects. These areas are divided according to their watershed boundaries. If two or more objects are situated along the same brook, the lower situated area is defined as its catchments minus the catchments of the closest higher situated object. The model encourages the study of an object situated in the sea from the time of deglaciation (c. 10,000 BP) to the time for the object due to positive shore displacement is situated on land or that a lake object has progressed to a wetland, however not longer than 18,000 AP. The model focuses on the object and its location in 100-year steps. The model is written in VisualBasic and is divided into two modules, a marine module and a lake module. The marine module deals with shoreline displacement, erosion and accumulation of postglacial fine-grained sediments and erosion of glacial clay. Inputs to the marine module are a digital elevation model (DEM), a digital map showing the extension of the objects and a marine quaternary map. The two maps are in raster formats with exactly the same formats (extension and cell sizes) as the DEM. For each time step the water depths at each pixel are calculated using a shore displacement equation. Next, the water depth changes due to sediment dynamics are calculated using the following rules; accumulation of fine-grained sediments are allowed if the pixel is situated within a future lake object; erosion of fine-grained sediment is allowed if the pixel is not within a future lake object and the marine quaternary map shows occurrence of postglacial

  20. Compatibility of Ugandan Schistosoma mansoni isolates with Biomphalaria snail species from Lake Albert and Lake Victoria

    Adriko, Moses; Standley, Claire J.; Tinkitina, Benjamin


    In order to investigate the capacity of being intermediate host for Schistosoma mansoni, the Ugandan F1 generation of Biomphalaria snail species that were laboratory-bred from parent populations originally collected from either Lake Victoria or Lake Albert was challenged with sympatric and non......-sympatric S. mansoni isolates. After a prepatent period of 20 days, a daily 10-hourly snail shedding for cercariae was done to determine the infection rate, cercarial production per hour and survival period of infected snails. The study suggests that when parasite strains from a different geographical origin...... is used for infection, survival of infected snails increase, leading to an increased transmission potential. Although earlier literature had indicated that the Lake Victoria Biomphalaria sudanica is refractory to S. mansoni, we showed that all Ugandan Biomphalaria spp., including B. sudanica from all...

  1. Stable isotope evolution and paleolimnology of ancient Lake Creede

    Rye, Robert O.; Bethke, Philip M.; Finkelstein, David B.


    and were dominated by CO2 produced by the oxidation of organic matter (hypolimnion). During Period III the lake remained stratified. The productive zone was in the hypolimnion, probably due to a thinning of the epilimnion resulting from an increase in the surface area of the lake or a decrease in input waters reflecting a climate change. An upsection increase in values δ18O for the heaviest samples during Periods ! and II indicates evaporative concentration of 18O and by, analogy, salinity in the hypolimnon. The δD-δ18O evolution of the lake is inferred on theoretical evaporation trends, comparison to Mono Lake, and measurement of the δD in fluid inclusions in a calcite pseudomorph after ikaite. The δD-δ18O composition of the lake water followed a curved path that eventually hooked over at a nearly constant δ18O value for the lake of 2% to 2%. Travetine (tufa) mounds formed along the inner and outer margins of the lake in a zone of mixing of warm, volcanic CO2-bearing, meteoric waters and lake water. Ikaite crystals formed on the mounds from unmixed saline lake water, probably below the thermocline. As the position of the thermocline deepened, likely following the spring runoff, the ikaite was replaced by calcite and the resulting "pearls" were covered with travertine deposited from mixed meteoric and lake waters. The upsection increase in δ18O values of the carbonates, the long period of invariance of large δ18OH2O values, the presence of brine shrimp fecal pellets, and the inferred hooked δD-δ18O path are consistent with evidence from other studies that Lake Creede obtained significant salinity rather early in its history and certainly by the time the lake became permanently stratified.

  2. Synthesis of lanthanum tris (mono-i-octyl phthalate)and its thermal stability for polyvinyl chloride


    A novel type of thermal stabilizer-lanthanum tris (mono-i-octyl phthalate) (LTMP) was synthesized by double-decomposition reaction of sodium mono-i-octyl phthalate with lanthanum chloride at 60℃.Sodium mono-i-octyl phthalate was prepared by sodium hydrate and mono-i-octyl phthalate prepared by reaction of isooctyl alcohol and phthalic anhydride in the presence of sulfuric acid catalyst at 110 ℃. The yield of lanthanum tris (mono-i-octyl phthalate) is about 84.5%. Its thermal stabilities were measured by heat-ageing oven test when incorporated into PVC. The experimental results show that the heat stability time is about 40min at 190 ℃ when adding 3phr (per hundred resin) to PVC. The thermal stability of this product is better than that of Ca-Zn complex and basic lead salt stabilizers, and equal to that of dibutyltin dilaurate.

  3. Water Quality Index for Assessment of Rudrasagar Lake Ecosystem, India

    Joyanta pal


    Full Text Available Water quality of lakes, rivers and reservoirs in developing countries like India is being degraded because of the contaminated inflows and surrounding influence. There is a serious need for appropriate water quality monitoring for future planning and management of Lake and other type of water resources. Quality of water in Rudrasagar Lake, Tripura, India has been investigated in this paper. Water Quality Index (WQI was applied in Rudrasagar Lake India using water quality parameters like pH, Turbidity, Conductivity, Hardness, Alkalinity, Dissolved Oxygen, Biochemical Oxygen Demand and Nitrate. Based on the importance of the parameter for aquatic life the relative weight is assigned to each water quality parameter ranged from 1 to 4. Tests were performed on site using electronic measuring device as well as on Laboratory with samples of water collected from different locations of Rudrasagar Lake. It shows that water quality of Rudrasagar Lake falls within the ‗good water‘ category but marginally. Continuous monitoring of Rudrasagar lake is suggested for proper management.

  4. Modeling Antarctic Subglacial Lake Filling and Drainage Cycles

    Dow, Christine F.; Werder, Mauro A.; Nowicki, Sophie; Walker, Ryan T.


    The growth and drainage of active subglacial lakes in Antarctica has previously been inferred from analysis of ice surface altimetry data. We use a subglacial hydrology model applied to a synthetic Antarctic ice stream to examine internal controls on the filling and drainage of subglacial lakes. Our model outputs suggest that the highly constricted subglacial environment of our idealized ice stream, combined with relatively high rates of water flow funneled from a large catchment, can combine to create a system exhibiting slow-moving pressure waves. Over a period of years, the accumulation of water in the ice stream onset region results in a buildup of pressure creating temporary channels, which then evacuate the excess water. This increased flux of water beneath the ice stream drives lake growth. As the water body builds up, it steepens the hydraulic gradient out of the overdeepened lake basin and allows greater flux. Eventually this flux is large enough to melt channels that cause the lake to drain. Lake drainage also depends on the internal hydrological development in the wider system and therefore does not directly correspond to a particular water volume or depth. This creates a highly temporally and spatially variable system, which is of interest for assessing the importance of subglacial lakes in ice stream hydrology and dynamics.

  5. Lake level fluctuations boost toxic cyanobacterial "oligotrophic blooms".

    Cristiana Callieri

    Full Text Available Global warming has been shown to strongly influence inland water systems, producing noticeable increases in water temperatures. Rising temperatures, especially when combined with widespread nutrient pollution, directly favour the growth of toxic cyanobacteria. Climate changes have also altered natural water level fluctuations increasing the probability of extreme events as dry periods followed by heavy rains. The massive appearance of Dolichospermum lemmermannii ( = planktonic Anabaena, a toxic species absent from the pelagic zone of the subalpine oligotrophic Lake Maggiore before 2005, could be a consequence of the unusual fluctuations of lake level in recent years. We hypothesized that these fluctuations may favour the cyanobacterium as result of nutrient pulses from the biofilms formed in the littoral zone when the lake level is high. To help verify this, we exposed artificial substrates in the lake, and evaluated their nutrient enrichment and release after desiccation, together with measurements of fluctuations in lake level, precipitation and D. lemmermannii population. The highest percentage of P release and the lowest C:P molar ratio of released nutrients coincided with the summer appearance of the D. lemmermannii bloom. The P pulse indicates that fluctuations in level counteract nutrient limitation in this lake and it is suggested that this may apply more widely to other oligotrophic lakes. In view of the predicted increase in water level fluctuations due to climate change, it is important to try to minimize such fluctuations in order to mitigate the occurrence of cyanobacterial blooms.

  6. Tracing the geochemical evolution of alkaline Lake Van, Turkey

    Kwiecien, Ola; Viehberg, Finn; Plessen, Birgit; Litt, Thomas; Tillman Meyer, Felix


    Terminal Lake Van, the world's largest soda basin, is characterised by Na-CO3-Cl water chemistry (Reimer et al., 2008), salinity of ~22 ‰ and high pH of ~9.7. The sedimentary record of the lake goes ca. 600 ka back and documents major climatic events over that period (Stockhecke et al., 2014). Alas, the longevity of the basin does not mean that it persisted unchanged over such a long time. Information collected within the ICDP PALEOVAN project clearly suggests that upon its birth the chemistry of early Lake Van was very different from its modern alkaline equivalent. Here we document, by means of proxy data, the changes in water chemistry in a transforming basin. Results of lithological (Stockhecke et al., 2014) and micropaleontological (ostracod, gastropod and diatom assemblages) analysis, combined with geochemical data (δ18O, δ13C, Mg/Ca, Sr/Ca) obtained from the biogenic and authigenic carbonate fraction imply, that early Lake Van was a relatively shallow, fresh-to-brackish and, most probably, open basin. Sedimentological information points to tectonic factors rather than climatic changes responsible for closing the lake ca. 430 ka ago. Reimer, A., Landmann, G., Kempe, S., 2008. Lake Van, Eastern Anatolia, Hydrochemistry and History. Aquat. Geochemistry 15, 195-222. Stockhecke, M., Sturm, M., Brunner, I., Schmincke, H.-U., Sumita, M., Kipfer, R., Cukur, D., Kwiecien, O., Anselmetti, F.S., 2014. Sedimentary evolution and environmental history of Lake Van (Turkey) over the past 600 000 years. Sedimentology.

  7. Health Disparities and Relational Well-Being between Multi- and Mono-Ethnic Asian Americans

    Zhang, Wei


    Focusing on Hawaii, a state with 21.3% of the population being multi-racial according to the 2010 U.S. Census, this study aims to examine the existence and nature of health disparities between mono- and multi-ethnic Asian Americans and the importance of Relational Well-Being in affecting the health of Asian Americans. A series of ordinary least…

  8. De kwalitatieve en semikwantitatieve bepaling van 6-mono-acetylmorfine in de urine van druggebruikers (I)

    Derks HJGM; van Twillert K; Zomer G


    In dit rapport wordt een analytische methode beschreven voor de bepaling van 6-mono-acetylmorfine in urine. Deze metaboliet van heroine is een marker voor heroine-gebruik en de bepaling ervan kan gebruikt worden om het gebruik van heroine van dat van morfine te onderscheiden. De methode is gebasee

  9. Synthesis and photochromic behavior of mono-,and biphotochromic system linked by p-phenylene bridge

    N.O.Mahmoodi; K.Tabatabaeian; A.Ghavidast


    The synthesis of mono- and bis-1,3-diazabicyclo[3.1.0]hex-3-ene derivatives with indole ring and p-phenylene spacer,which behave as photochromic materials,is reported.The structure-photochromic behavior relationship (SPBR) of the synthesized compounds has been analyzed.

  10. Literature review on cyclic lateral loading effects of mono-bucket foundations

    Kapitanov, Lachezar Rosenov; Duroska, Peter; Quirante, Cesar Antonio Garcia


    calculation is highly demanded at the different design phases. The intention of the current study is to present, review and summarize the existing techniques to assess the effect of cyclic loading on Mono-Bucket foundations while emphasizing the advantage and disadvantage of each of them. Additionally...

  11. Synthesis of Versatile Building Blocks through Asymmetric Hydrogenation of Functionalized Itaconic Acid Mono-Esters

    Hekking, Koen F.W.; Lefort, Laurent; Vries, André H.M. de; Delft, Floris L. van; Schoemaker, Hans E.; Vries, Johannes G. de; Rutjes, Floris P.J.T.


    The rhodium-catalyzed asymmetric hydrogenation of several β-substituted itaconic acid mono-esters, using a library of monodentate phosphoramidite and phosphite ligands is described. Two β-alkyl-substituted substrates were readily hydrogenated by the rhodium complex Rh(COD)2BF4 in combination with (S

  12. Upgrading of the Mono Media Filters in Water Treatment Plants by Changing Filter Media

    L Rezaei


    Full Text Available "n "n "nBackground and Objectives:Dual media filters have two different layer beds consist of sand and Anthracite. Advantage of dual media filters is longer run duration and more filtration rate. The purpose of this study was to achieve a performable model to improve single media Filters in water treatment plants."nMaterials and Methods: in this cross-sectional study, two pilots; mono and dual media were made and in a 5 month period samples taking were done. Total samples taken from input and output of each pilot, was 40. The samples then introduced for the measurment of turbidity and total organic carbon. Meanwhile the filters head loss also quantified in 40 times head loss measurement was done."nResults: Average turbidity removal in mono and two layer pilots were 63 and 65 percent respectively. Average removal of Total Organic Carbon in mono and two media pilots were 40 and 66 percent respectively. Head loss in dual and single media pilots were 0 .68 and 1.15 m respectively."nConclusion: Although average torbidity removal disparity between two pilots was not significant the amount of total organic carbon removed was considerable. Average head loss in single media pilot was more than dual media type. Ratio of UFRV in dual media to mono media filter was 51:30 it shows that filtration rate capacity will be improved up to70 percent by changing media type.

  13. Preparation of mono- and diacetyl 4,4′-dimethylbiphenyl and their corresponding carboxylic acids

    Titinchi, Salam J.J.; Kamounah, Fadhil S.; Abbo, Hanna S.


    dimethylbiphenyls. In chloroalkane or carbon disulfide solvent, the yields of isomers were in the order: 2 -> 3-; in nitromethane 3-isomer predominated. On the other hand diacetylation of the hydrocarbon gave only the 2,3′-diacetyl isomer. The mono- and di-ketones are converted to the corresponding carboxylic acids...

  14. Synthesis of hierarchical zeolites using an inexpensive mono-quaternary ammonium surfactant as mesoporogen.

    Zhu, Xiaochun; Rohling, Roderigh; Filonenko, Georgy; Mezari, Brahim; Hofmann, Jan P; Asahina, Shunsuke; Hensen, Emiel J M


    A simple amphiphilic surfactant containing a mono-quaternary ammonium head group (N-methylpiperidine) is effective in imparting substantial mesoporosity during synthesis of SSZ-13 and ZSM-5 zeolites. Highly mesoporous SSZ-13 prepared in this manner shows greatly improved catalytic performance in the methanol-to-olefins reaction compared to bulk SSZ-13.

  15. Experimental damping assessment of a full scale offshore mono bucket foundation

    Gres, Szymon; Fejerskov, Morten; Ibsen, Lars Bo


    This paper quantifies the system damping of a offshore meteorological mast supported by a Mono Bucket foundation based on a long-term experimental campaign. The structure is located at Dogger Bank west, North Sea, and equipped with a measurement system monitoring acceleration, strain, inclination...

  16. Forced vibration and wave propagation in mono-coupled periodic structures

    Ohlrich, Mogens


    This paper describes the wave propagation and vibration characteristics of mono-coupled structures which are of spatially periodic nature. The receptance approach to periodic structure theory is applied to study undamped periodic systems with composite structural elements; particular emphasis...... of the determination of the junction-receptance. The influence of such a disorder is illustrated by a simple example...

  17. Improving Enantioselectivity by Using a Mono-Sulphonated Diphosphine as Ligand for Homogeneous Imine Hydrogenation

    Lansink, Cornelis; Vries, Johannes G. de


    The Rhodium catalysed hydrogenation of acetophenone N-benzylimine using mono-sulphonated (2S,4S)-bis-(diphenylphosphino)pentane as ligand gives the corresponding amine with 94% e.e., whereas use of the di-sulphonated ligand yields product with 2% e.e.

  18. IRIS Toxicological Review of Ethylene Glycol Mono-Butyl Ether (Egbe) (Interagency Science Discussion Draft)

    EPA released the draft report, Toxicological Review for Ethylene Glycol Mono-Butyl Ether , that was distributed to Federal agencies and White House Offices for comment during the Science Discussion step of the IRIS Assessment Development Process. Comments received from ot...

  19. IRIS Toxicological Review of Ethylene Glycol Mono Butyl Ether (Egbe) (Final Report)

    EPA has finalized the Toxicological Review of Ethylene Glycol Mono Butyl Ether: in support of the Integrated Risk Information System (IRIS). Now final, this assessment may be used by EPA’s program and regional offices to inform decisions to protect human health.

  20. Specific fluorescent detection of fibrillar α-synuclein using mono- and trimethine cyanine dyes

    Volkova, K.D.; Kovalska, V.B.; Balanda, A.O.; Losytskyy, M.Yu; Golub, A.G.; Vermeij, R.J.; Subramaniam, V.; Tolmachev, O.I.; Yarmoluk, S.M.


    With the aim of searching of novel amyloid-specific fluorescent probes the ability of series of mono- and trimethine cyanines based on benzothiazole, pyridine and quinoline heterocycle end groups to recognize fibrillar formations of α-synuclein (ASN) was studied. For the first time it was revealed t


    Zhang Tao; Ma Changzheng; Zhang Qun; Zhang Shouhong


    A method for mono-pulse radar 3-D imaging in stepped tracking mode is presented and the amplitude linear modulation of error signals in stepped tracking mode is analyzed with its compensation method followed, so the problem of precisely tracking of target is solved. Finally the validity of these methods is proven by the simulation results.

  2. The acute effects of mono(2-ethylhexyl)phthalate (MEHP) on testes of prepubertal Wistar rats

    Dalgaard, M.; Nellemann, Christine Lydia; Lam, Henrik Rye;


    A single oral dose of 400 mg/kg body weight of mono(2-ethylhexyl)phthalate (MEHP), the testis toxic metabolite of di(2-ethylhexyl)phthalate. was given to 28-day-old male Wistar rats and the testis toxic effects were investigated 3, 6. and 12 h after exposure. Detachment and sloughing of germ cell...

  3. Endotoxin testing of proteins for parenteral administration using the Mono Mac 6 assay

    Moesby, Lise; Hansen, E W; Christensen, J D


    Pharmaceutical products containing proteins cause problems in testing for endotoxin and pyrogens. Many proteins interfere with the LAL test and the proteins are immunogenic in rabbits. The monocytic cell line Mono Mac 6 is an alternative assay for detection of endotoxin and other pyrogens....

  4. One-step selection of Vaccinia virus-binding DNA aptamers by MonoLEX

    Stöcklein Walter


    Full Text Available Abstract Background As a new class of therapeutic and diagnostic reagents, more than fifteen years ago RNA and DNA aptamers were identified as binding molecules to numerous small compounds, proteins and rarely even to complete pathogen particles. Most aptamers were isolated from complex libraries of synthetic nucleic acids by a process termed SELEX based on several selection and amplification steps. Here we report the application of a new one-step selection method (MonoLEX to acquire high-affinity DNA aptamers binding Vaccinia virus used as a model organism for complex target structures. Results The selection against complete Vaccinia virus particles resulted in a 64-base DNA aptamer specifically binding to orthopoxviruses as validated by dot blot analysis, Surface Plasmon Resonance, Fluorescence Correlation Spectroscopy and real-time PCR, following an aptamer blotting assay. The same oligonucleotide showed the ability to inhibit in vitro infection of Vaccinia virus and other orthopoxviruses in a concentration-dependent manner. Conclusion The MonoLEX method is a straightforward procedure as demonstrated here for the identification of a high-affinity DNA aptamer binding Vaccinia virus. MonoLEX comprises a single affinity chromatography step, followed by subsequent physical segmentation of the affinity resin and a single final PCR amplification step of bound aptamers. Therefore, this procedure improves the selection of high affinity aptamers by reducing the competition between aptamers of different affinities during the PCR step, indicating an advantage for the single-round MonoLEX method.

  5. Classification of All Associative Mono-n-ary Algebras with 2 Elements

    Stephan Dominique Andres


    of these associative mono--ary algebras with 2 elements for even ≥2 and 6 for odd ≥3. These algebras are described explicitly. It is shown that a similar result is impossible for algebras with at least 4 elements. An application concerning the assignment of a control bit to a string is given.

  6. Bioconversion of Mono- and Sesquiterpenoids by Recombinant Human Cytochrome P450 Monooxygenases

    Julsing, Mattijs K.; Fichera, Mario A.; Malz, Frank; Ebbelaar, Monique; Bos, Rein; Woerdenbag, Herman J.; Quax, Wim J.; Kayser, Oliver


    Cytochrome P450 monooxygenases play an important role in the biosynthesis and metabolism of terpenoids. We explored the potential of recombinant human liver cytochrome P450 monooxygenases CYP1A2, CYP2C9, and CYP3A4, heterologously expressed in Escherichia coli, to convert mono- and sesquiterpenoids

  7. Síntesis de mono y diitaconatos de alquilo y arilo

    Francisco J. Sánchez


    Full Text Available Se presenta una técnica para la síntesis en laboratorio de mono y diitaconatos y la separación de los mismos por extracción selectiva con solventes orgánicos. La pureza de los productos se determina por cromatografía en capa fina y por espectroscopia infrarroja.

  8. Some transition metal complexes derived from mono- and di-ethynyl perfluorobenzenes

    Armitt, D.J.; Bruce, M.I.; Gaudio, M.; Zaitseva, N.N.; Skelton, B.W.; White, A.H.; Le Guennic, B.; Halet, J.-F.; Fox, M.A.; Roberts, R.L.; Hartl, F.; Low, P.J.


    Transition metal alkynyl complexes containing perfluoroaryl groups have been prepared directly from trimethylsilyl-protected mono- and di-ethynyl perfluoroarenes by simple desilylation/metallation reaction sequences. Reactions between Me3SiC CC6F5 and RuCl(dppe)Cp'[Cp' = Cp, Cp*] in the presence of

  9. (II) and Zn (II) ions in mono-element and the bi-element aqueous ...


    and zinc (II) ions (Cu2+ and Zn2+) in mono-element and binary aqueous solutions. The experiments were carried out .... (1998) proposed a model that allows to evaluate the adsorption capacity of ...... 2(8):875- 878. Tien CT, Huang CP (1991).

  10. 76 FR 38026 - Diethylene Glycol Mono Butyl Ether; Exemption From the Requirement of a Tolerance


    ... butyl ether, also a glycol ether differing in only one ethyl group from DEGBE. These data were used to... monobutyl ether, also a glycol ether differing only in one ethyl group. This data was used to assess the... AGENCY 40 CFR Part 180 Diethylene Glycol Mono Butyl Ether; Exemption From the Requirement of a...

  11. Mercury levels in herring gulls and fish: 42 years of spatio-temporal trends in the Great Lakes.

    Blukacz-Richards, E Agnes; Visha, Ariola; Graham, Matthew L; McGoldrick, Daryl L; de Solla, Shane R; Moore, David J; Arhonditsis, George B


    Total mercury levels in aquatic birds and fish communities have been monitored across the Canadian Great Lakes by Environment and Climate Change Canada (ECCC) for the past 42 years (1974-2015). These data (22 sites) were used to examine spatio-temporal variability of mercury levels in herring gull (Larus argentatus) eggs, lake trout (Salvelinus namaycush), walleye (Sander vitreus), and rainbow smelt (Osmerus mordax). Trends were quantified with dynamic linear models, which provided time-variant rates of change of mercury concentrations. Lipid content (in both fish and eggs) and length in fish were used as covariates in all models. For the first three decades, mercury levels in gull eggs and fish declined at all stations. In the 2000s, trends for herring gull eggs reversed at two sites in Lake Erie and two sites in Lake Ontario. Similar trend reversals in the 2000s were observed for lake trout in Lake Superior and at a single station in Lake Ontario. Mercury levels in lake trout continued to slowly decline at all of the remaining stations, except for Lake Huron, where the levels remained stable. A post-hoc Bayesian regression analysis suggests strong trophic interactions between herring gulls and rainbow smelt in Lake Superior and Lake Ontario, but also pinpoints the likelihood of a trophic decoupling in Lake Huron and Lake Erie. Continued monitoring of mercury levels in herring gulls and fish is required to consolidate these trophic shifts and further evaluate their broader implications.

  12. Ecological and environmental water demand of the lakes in the Haihe-Luanhe Basin of North China


    The purpose of this paper is to present a brief concept of the ecological and environmental water demand of lake. The present situation and affecting factors of lake ecological system in the Haihe-Luanhe Basin of North China was analyzed. The calculating method of the ecological and environmental water demand of the lake basis on the water body and the calculating method of the ecological and environmental water demand of the lake basis on the aquatic ecosystem, wetland and vegetation were compared and discussed. As the examples of Baiyangdian Lake and Beidagang Lake in Haihe-Luanhe river basin, the ecological and environmental water demand of the two lakes was calculated to be 27× 108m3 . It is 6.75 times to the water demand according to the calculating method of the ecological and environmental water demand of the lake basis on the water body. The research result indicated: ( 1 ) The calculating methods of the ecological and environmental water demand of the lake basis on the aquatic ecosystem should be better than only basis on the water body of lake. (2) The data, such as area of the vegetation kind around and in the lake, the vegetation coefficient, the evaporating amount of the vegetation and the vegetation water demand itself around and in the lake are lack and urgent need. Some suggestions for controlling and regulating the water resource of the lake in North China were proposed.

  13. Regional impacts of ultrafine particle emissions from the surface of the Great Lakes

    S. H. Chung


    Full Text Available Quantifying the impacts of aerosols on climate requires a detailed knowledge of both the anthropogenic and the natural contributions to the aerosol population. Recent work has suggested a previously unrecognized natural source of ultrafine particles resulting from breaking waves at the surface of large freshwater lakes. This work is the first modeling study to investigate the potential for this newly discovered source to affect the aerosol number concentrations on regional scales. Using the WRF-Chem modeling framework, the impacts of wind-driven aerosol production from the surface of the Great Lakes were studied for a July 2004 test case. Simulations were performed for a base case with no lake surface emissions, a case with lake surface emissions included, and a default case wherein large freshwater lakes emit marine particles as if they were oceans. Results indicate that the lake surface emissions can enhance the surface level aerosol number concentration by ∼20 % over the remote northern Great Lakes and by ∼5 % over other parts of the Great Lakes. These results were highly sensitive the nucleation parameterization within WRF-Chem; when the nucleation process was deactivated, surface-layer enhancements from the lake emissions increased to as much as 200 %. The results reported here have significant uncertainties associated with the lake emission parameterization and the way ultrafine particles are modeled within WRF-Chem. Nevertheless, the magnitude of the impacts found in this study suggest that further study of this phenomena is merited.

  14. Ballast water treatment techniques: review and suggestions regarding use in the Arctic and Great Lakes

    Brink, van den A.M.; Kaag, N.H.B.M.; Sneekes, A.C.


    The retreating ice cover opens up the opportunity for new shipping routes, and consequently shipping traffic in the Arctic region is increasing and with this the risk of introducing non-indigenous species (NIS) via ballast water. Ballast water must therefore be treated to prevent the transport of NI

  15. Prevalence, Risk Factors, and Treatment Outcomes of Isoniazid- and Rifampicin-Mono-Resistant Pulmonary Tuberculosis in Lima, Peru.

    Leonela Villegas

    Full Text Available Isoniazid and rifampicin are the two most efficacious first-line agents for tuberculosis (TB treatment. We assessed the prevalence of isoniazid and rifampicin mono-resistance, associated risk factors, and the association of mono-resistance on treatment outcomes.A prospective, observational cohort study enrolled adults with a first episode of smear-positive pulmonary TB from 34 health facilities in a northern district of Lima, Peru, from March 2010 through December 2011. Participants were interviewed and a sputum sample was cultured on Löwenstein-Jensen (LJ media. Drug susceptibility testing was performed using the proportion method. Medication regimens were documented for each patient. Our primary outcomes were treatment outcome at the end of treatment. The secondary outcome included recurrent episodes among cured patients within two years after completion of the treatment.Of 1292 patients enrolled, 1039 (80% were culture-positive. From this subpopulation, isoniazid mono-resistance was present in 85 (8% patients and rifampicin mono-resistance was present in 24 (2% patients. In the multivariate logistic regression model, isoniazid mono-resistance was associated with illicit drug use (adjusted odds ratio (aOR = 2.10; 95% confidence interval (CI: 1.1-4.1, and rifampicin mono-resistance was associated with HIV infection (aOR = 9.43; 95%CI: 1.9-47.8. Isoniazid mono-resistant patients had a higher risk of poor treatment outcomes including treatment failure (2/85, 2%, p-value<0.01 and death (4/85, 5%, p<0.02. Rifampicin mono-resistant patients had a higher risk of death (2/24, 8%, p<0.01.A high prevalence of isoniazid and rifampicin mono-resistance was found among TB patients in our low HIV burden setting which were similar to regions with high HIV burden. Patients with isoniazid and rifampicin mono-resistance had an increased risk of poor treatment outcomes.

  16. Glacial lake evolution in the southeastern Tibetan Plateau and the cause of rapid expansion of proglacial lakes linked to glacial-hydrogeomorphic processes

    Song, Chunqiao; Sheng, Yongwei; Ke, Linghong; Nie, Yong; Wang, Jida


    Glacial lakes, as an important component of the cryosphere in the southeastern Tibetan Plateau (SETP) in response to climate change, pose significant threats to the downstream lives and properties of people, engineering construction, and ecological environment via outburst floods, yet we currently have limited knowledge of their distribution, evolution, and the driving mechanism of rapid expansions due to the low accessibility and harsh natural conditions. By integrating optical imagery, satellite altimetry and digital elevation model (DEM), this study presents a regional-scale investigation of glacial lake dynamics across two river basins of the SETP during 1988-2013 and further explores the glacial-hydrogeomorphic process of rapidly expanding lakes. In total 1278 and 1396 glacial lakes were inventoried in 1988 and 2013, respectively. Approximately 92.4% of the lakes in 2013 are not in contact with modern glaciers, and the remaining 7.6% includes 27 (1.9%) debris-contact lakes (in contact with debris-covered ice) and 80 (5.7%) cirque lakes. In categorizing lake variations, we found that debris-contact proglacial lakes experienced much more rapid expansions (∼75%) than cirque lakes (∼7%) and non-glacier-contact lakes (∼3%). To explore the cause of rapid expansion for these debris-contact lakes, we further investigated the mass balance of parent glaciers and elevation changes in lake surfaces and debris-covered glacier tongues using time-series Landsat images, ICESat altimetry, and DEM. Results reveal that the upstream expansion of debris-contact proglacial lakes was not directly associated with rising water levels but with a geomorphological alternation of upstream lake basins caused by melting-induced debris subsidence at glacier termini. This suggests that the hydrogeomorphic process of glacier thinning and retreat, in comparison with direct glacial meltwater alone, may have played a dominant role in the recent glacial lake expansion observed across the

  17. Isotopic and hydrologic responses of small, closed lakes to climate variability: Comparison of measured and modeled lake level and sediment core oxygen isotope records

    Steinman, Byron A.; Abbott, Mark B.; Nelson, Daniel B.; Stansell, Nathan D.; Finney, Bruce P.; Bain, Daniel J.; Rosenmeier, Michael F.


    Simulations conducted using a coupled lake-catchment isotope mass balance model forced with continuous precipitation, temperature, and relative humidity data successfully reproduce (within uncertainty limits) long-term (i.e., multidecadal) trends in reconstructed lake surface elevations and sediment core oxygen isotope (δ18O) values at Castor Lake and Scanlon Lake, north-central Washington. Error inherent in sediment core dating methods and uncertainty in climate data contribute to differences in model reconstructed and measured short-term (i.e., sub-decadal) sediment (i.e., endogenic and/or biogenic carbonate) δ18O values, suggesting that model isotopic performance over sub-decadal time periods cannot be successfully investigated without better constrained climate data and sediment core chronologies. Model reconstructions of past lake surface elevations are consistent with estimates obtained from aerial photography. Simulation results suggest that precipitation is the strongest control on lake isotopic and hydrologic dynamics, with secondary influence by temperature and relative humidity. This model validation exercise demonstrates that lake-catchment oxygen isotope mass balance models forced with instrumental climate data can reproduce lake hydrologic and isotopic variability over multidecadal (or longer) timescales, and therefore, that such models could potentially be used for quantitative investigations of paleo-lake responses to hydroclimatic change.

  18. Changes in ice cover thickness and lake level of Lake Hoare, Antarctica - Implications for local climatic change

    Wharton, Robert A., Jr.; Mckay, Christopher P.; Clow, Gary D.; Andersen, Dale T.; Simmons, George M., Jr.; Love, F. G.


    Results are reported from 10 years of ice-thickness measurements at perennially ice-covered Lake Hoare in southern Victoria Land, Antarctica. The ice cover of this lake had been thinning steadily at a rate exceeding 20 cm/yr during the last decade but seems to have recently stabilized at a thickness of 3.3 m. Data concerning lake level and degree-days above freezing are presented to show the relationship between peak summer temperatures and the volume of glacier-derived meltwater entering Lake Hoare each summer. From these latter data it is inferred that peak summer temperatures have been above 0 C for a progressively longer period of time each year since 1972. Possible explanations for the thinning of the lake ice are considered. The thickness of the ice cover is determined by the balance between freezing during the winter and ablation that occurs all year but maximizes in summer. It is suggested that the term most likely responsible for the change in the ice cover thickness at Lake Hoare is the extent of summer melting, consistent with the rising lake levels.

  19. Changes in Glaciers and Glacial Lakes and the Identification of Dangerous Glacial Lakes in the Pumqu River Basin, Xizang (Tibet

    Tao Che


    Full Text Available Latest satellite images have been utilized to update the inventories of glaciers and glacial lakes in the Pumqu river basin, Xizang (Tibet, in the study. Compared to the inventories in 1970s, the areas of glaciers are reduced by 19.05% while the areas of glacial lakes are increased by 26.76%. The magnitudes of glacier retreat rate and glacial lake increase rate during the period of 2001–2013 are more significant than those for the period of the 1970s–2001. The accelerated changes in areas of the glaciers and glacial lakes, as well as the increasing temperature and rising variability of precipitation, have resulted in an increased risk of glacial lake outburst floods (GLOFs in the Pumqu river basin. Integrated criteria were established to identify potentially dangerous glacial lakes based on a bibliometric analysis method. It is found, in total, 19 glacial lakes were identified as dangerous. Such finding suggests that there is an immediate need to conduct field surveys not only to validate the findings, but also to acquire information for further use in order to assure the welfare of the humans.

  20. Ecosystem health assessment of urban rivers and lakes-Case study of "the six lakes" in Beijing,China


    The assessment of the ecosystem health of urban rivers and lakes is the scientific basis for their management and ecological restoration.This study developed a three-level indicator system for its assessment.The results indicated that:Zhonghai and Nanhai are in the state of transition from unhealthy to critical state and all the other lakes are in unhealthy states.Water environmental quality,structure and function of the aquatic ecosystem,and the structure of waterfront areas were the constraints.Nanhai was ranked as poor and the others were all ranked as very poor.However,the ecological environment of Zhonghai and Nanhai were better than the others,the sums of the degree of membership to the healthy state and critical state were all close to 0.6.and the restorations of these lakes were moderate.The sums of the degree of membership to the healthy state and critical state of the other lakes were under 0.3,as it was difficult to restore these lakes.Some suggestions on scientific management and ecological restoration of the six lakes were improve the water quality of six lakes and the water ecosystem and waterfront areas.

  1. Life history differences between fat and lean morphs of lake charr (Salvelinus namaycush) in Great Slave Lake, Northwest Territories, Canada

    Hansen, Michael J.; Nate, Nancy A.; Chavarie, Louise; Muir, Andrew M.; Zimmerman, Mara S.; Krueger, Charles C.


    Life history characteristics (size, age, plumpness, buoyancy, survival, growth, and maturity) were compared between fat and lean morphs of lake charr Salvelinus namaycush in Great Slave Lake, Canada, to determine if differences may reflect effects of resource polymorphism. Lake charr were sampled using graded-mesh gill nets set in three depth strata. Of 236 lake charr captured, 122 were a fat morph and 114 were a lean morph. Males and females did not differ from each other in any attributes for either fat or lean morphs. The fat morph averaged 15 mm longer, 481 g heavier, and 4.7 years older than the lean morph. The fat morph averaged 26% heavier and 48% more buoyant at length than the lean morph. Survival of the fat morph was 1.7% higher than that of the lean morph. The fat morph grew at a slower annual rate to a shorter asymptotic length than the lean morph. Fat and lean morphs matured at similar lengths and ages. We concluded that the connection between resource polymorphism and life histories in lean versus fat lake charr suggests that morph-specific restoration objectives may be needed in lakes where lake charr diversity is considered to be a restoration goal.

  2. Origin and Distribution Of Glacial Lakes: A Case Study In Tista Basin, India

    Kulkarni, A. V.


    Himalayan glaciers are experiencing retreat due to changes in the temperature and precipitation pattern. Retreating glaciers depending upon the underlying bed topography can cause lake formation near terminus. Therefore formation and draining of lakes in the glaciated terrain of Himalaya is commonly observed. However, few lakes became stable under suitable geomorphologic conditions and grow sufficiently large to threaten population and infrastructure in downstream. In this investigation changes in glacial lakes in Tista basin were studied using satellite images for a period between 1989 and 2010. The Tista basin in Sikkim covers approximately 7096 sq km area and the total glaciated area is 501± 29 sq km. During the period of investigation the lake area is increased from 6.6 ± 0.8 km2 to 9.6 ± 1.1 km2 due to formation of new lakes and also due to expansion of existing lake. Out of 23 lakes, 16 showed variable increase in area. We have also observed formation of stable proglacial lake due to coalescence of small supra glacial lakes on Changsang and South Lhonak Glacier. The size of lake near South Lhonak Glacier was increased from 18 to 126 ha from 1978 to 2014 (Figure). Therefore detail field investigations were carried out to understand volume and extent of ice in end moraine. The water volume was estimated as 53 million m3 using bathymetric survey and ice at the core of terminal moraines was mapped using resistivity survey. These investigations suggests a possibility of catastrophic outburst flood, if moraine dam breached under extreme weather conditions. Therefore, mitigation strategy is needed to improve safety of people living in the region. In addition, numerous remote sensing based investigations have mapped more than 300 lakes in the glaciated terrain in India, therefore, a national program to monitor glacier lakes and strategy to mitigate possible disaster is needed. Figure: Expansion of the lake near South Lhonak glacier from year 1990 to 2014.

  3. Wind-driven Water Bodies : a new paradigm for lake geology

    Nutz, A.; Schuster, M.; Ghienne, J. F.; Roquin, C.; Bouchette, F. A.


    In this contribution we emphasize the importance in some lakes of wind-related hydrodynamic processes (fair weather waves, storm waves, and longshore, cross-shore and bottom currents) as a first order forcing for clastics remobilization and basin infill. This alternative view contrasts with more classical depositional models for lakes where fluvial-driven sedimentation and settling dominates. Here we consider three large lakes/paleo-lakes that are located in different climatic and geodynamic settings: Megalake Chad (north-central Africa), Lake Saint-Jean (Québec, Canada), and Lake Turkana (Kenya, East African Rift System). All of these three lake systems exhibit well developed modern and ancient high-energy littoral morphosedimentary structures which directly derive from wind-related hydrodynamics. The extensive paleo-shorelines of Megalake Chad are composed of beach-foredune ridges, spits, wave-dominated deltas, barriers, and wave-ravinment surface. For Lake Saint-Jean the influence of wind is also identified below the wave-base at lake bottom from erosional surfaces, and sediment drifts. In the Lake Turkana Basin, littoral landforms and deposits are identified for three different time intervals (today, Holocene, Plio-Pleistocene) evidencing that wind-driven hydrodynamics can be preserved in the geological record. Moreover, a preliminary global survey suggests that numerous modern lakes (remote sensing) and paleo-lakes (bibliographic review) behave as such. We thus coin the term "Wind-driven Water Bodies" (WWB) to refer to those lake systems where sedimentation (erosion, transport, deposition) is dominated by wind-induced hydrodynamics at any depth, as it is the case in the marine realm for shallow seas. Integrating wind forcing in lake models has strong implications for basin analysis (paleoenvironments and paleoclimates restitutions, resources exploration), but also for coastal engineering, wildlife and reservoirs management, or leisure activities.

  4. Highly divergent mussel lineages in isolated Indonesian marine lakes

    de Leeuw, Christiaan A.; Knegt, Bram; Maas, Diede L.; de Voogd, Nicole J.; Abdunnur; Suyatna, Iwan; Peijnenburg, Katja T.C.A.


    Marine lakes, with populations in landlocked seawater and clearly delineated contours, have the potential to provide a unique model to study early stages of evolution in coastal marine taxa. Here we ask whether populations of the mussel Brachidontes from marine lakes in Berau, East Kalimantan (Indonesia) are isolated from each other and from the coastal mangrove systems. We analyzed sequence data of one mitochondrial marker (Cytochrome Oxidase I (COI)), and two nuclear markers (18S and 28S). In addition, we examined shell shape using a geometric morphometric approach. The Indonesian populations of Brachidontes spp. harbored four deeply diverged lineages (14–75% COI corrected net sequence divergence), two of which correspond to previously recorded lineages from marine lakes in Palau, 1,900 km away. These four lineages also showed significant differences in shell shape and constitute a species complex of at least four undescribed species. Each lake harbored a different lineage despite the fact that the lakes are separated from each other by only 2–6 km, while the two mangrove populations, at 20 km distance from each other, harbored the same lineage and shared haplotypes. Marine lakes thus represent isolated habitats. As each lake contained unique within lineage diversity (0.1–0.2%), we suggest that this may have resulted from in situdivergence due to isolation of founder populations after the formation of the lakes (6,000–12,000 years before present). Combined effects of stochastic processes, local adaptation and increased evolutionary rates could produce high levels of differentiation in small populations such as in marine lake environments. Such short-term isolation at small spatial scales may be an important contributing factor to the high marine biodiversity that is found in the Indo-Australian Archipelago. PMID:27761314

  5. Highly divergent mussel lineages in isolated Indonesian marine lakes

    Leontine E. Becking


    Full Text Available Marine lakes, with populations in landlocked seawater and clearly delineated contours, have the potential to provide a unique model to study early stages of evolution in coastal marine taxa. Here we ask whether populations of the mussel Brachidontes from marine lakes in Berau, East Kalimantan (Indonesia are isolated from each other and from the coastal mangrove systems. We analyzed sequence data of one mitochondrial marker (Cytochrome Oxidase I (COI, and two nuclear markers (18S and 28S. In addition, we examined shell shape using a geometric morphometric approach. The Indonesian populations of Brachidontes spp. harbored four deeply diverged lineages (14–75% COI corrected net sequence divergence, two of which correspond to previously recorded lineages from marine lakes in Palau, 1,900 km away. These four lineages also showed significant differences in shell shape and constitute a species complex of at least four undescribed species. Each lake harbored a different lineage despite the fact that the lakes are separated from each other by only 2–6 km, while the two mangrove populations, at 20 km distance from each other, harbored the same lineage and shared haplotypes. Marine lakes thus represent isolated habitats. As each lake contained unique within lineage diversity (0.1–0.2%, we suggest that this may have resulted from in situdivergence due to isolation of founder populations after the formation of the lakes (6,000–12,000 years before present. Combined effects of stochastic processes, local adaptation and increased evolutionary rates could produce high levels of differentiation in small populations such as in marine lake environments. Such short-term isolation at small spatial scales may be an important contributing factor to the high marine biodiversity that is found in the Indo-Australian Archipelago.

  6. The response of Lake Tahoe to climate change

    Sahoo, G.B.; Schladow, S.G.; Reuter, J.E.; Coats, R.; Dettinger, M.; Riverson, J.; Wolfe, B.; Costa-Cabral, M.


    Meteorology is the driving force for lake internal heating, cooling, mixing, and circulation. Thus continued global warming will affect the lake thermal properties, water level, internal nutrient loading, nutrient cycling, food-web characteristics, fish-habitat, aquatic ecosystem, and other important features of lake limnology. Using a 1-D numerical model - the Lake Clarity Model (LCM) - together with the down-scaled climatic data of the two emissions scenarios (B1 and A2) of the Geophysical Fluid Dynamics Laboratory (GFDL) Global Circulation Model, we found that Lake Tahoe will likely cease to mix to the bottom after about 2060 for A2 scenario, with an annual mixing depth of less than 200 m as the most common value. Deep mixing, which currently occurs on average every 3-4 years, will (under the GFDL B1 scenario) occur only four times during 2061 to 2098. When the lake fails to completely mix, the bottom waters are not replenished with dissolved oxygen and eventually dissolved oxygen at these depths will be depleted to zero. When this occurs, soluble reactive phosphorus (SRP) and ammonium-nitrogen (both biostimulatory) are released from the deep sediments and contribute approximately 51 % and 14 % of the total SRP and dissolved inorganic nitrogen load, respectively. The lake model suggests that climate change will drive the lake surface level down below the natural rim after 2085 for the GFDL A2 but not the GFDL B1 scenario. The results indicate that continued climate changes could pose serious threats to the characteristics of the Lake that are most highly valued. Future water quality planning must take these results into account.

  7. Enhanced nighttime gas emissions from a lake

    Podgrajsek, E.; Sahlée, E.; Rutgersson, A.


    Methane (CH4) and carbon dioxide (CO2) are two important greenhouse gases. Previous studies have shown that lakes can be important natural sources of atmospheric CH4 and CO2. It is therefore important to monitor the fluxes of these gases between lakes and the atmosphere in order to understand the processes that govern the exchange. Most previous lake flux studies are based on chamber measurements, by using the eddy covariance method, the resolution in time and in space of the fluxes is increased, which gives more information on the governing processes. Eddy covariance measurements at a Swedish lake show that both methane fluxes (FCH4 ) and carbon dioxide fluxes (FCO2 ) experience high nighttime fluxes for a large part of the data set (largest median FCH4night ≈ 13 nmol m2 s-1 and smallest median FCH4day ≈ 4.0 nmol m-2 s-1, largest median FCO2night ≈ 0.2 μmol m2 s-1 and smallest median FCO2day ≈ 0.02 μmol m-2 s-1, with larger variability during night). For the diel cycle of the CH4 fluxes it is suggested that water side convection could enhance the transfer velocity, transport CH4 rich water to the surface, as well as trigger ebullition. The high nighttime CO2 fluxes could to a large extent be explained with enhanced transfer velocities due to water side convection. If gas fluxes are not measured during nighttime, when water side convection normally is generated, periods of potential high gas flux might be missed and estimations of the total amount of gas released from lakes to the atmosphere will be biased.

  8. Surface seiches in Flathead Lake, Montana

    Kirillin, Georgiy; Lorang, Mark; Gotschalk, Chris; Lippmann, Tom


    Flathead Lake— the largest freshwater lake in the western USA—undergoes significant short-term water level oscillations due to standing barotropic waves (seiches). Large surface area and several embayments cause high amplitudes and complicated spatial pattern of the seiches. We used water level records from 12 sites distributed around the lake and the results of numerical circulation modeling to establish the modal composition of seiches, the two-dimensional wave shape, and current patterns. For this, we directly applied harmonic analysis to the output of a full circulation model. Compared to the traditional reduced eigenvalue problem, the proposed approach allows modal separation of real datasets that is potentially advantageous for analysis of the resonant response to periodic wind forcing. Surprisingly, both model results and observations demonstrated predominance of the 'two-node' horizontal mode, whereas the usually most acute 'one-node' mode was attenuated by the large shallow bay connected through a narrow straight to the main lake basin. Energy of several higher modes was concentrated around the mouth of the main inflow suggesting their strong effect on the redistribution of the inflow waters and suspended matter within the lake. The rotary spectral analysis revealed rotational character of two particular modes and localized potential upwelling/downwelling areas, where water-sediment matter transport could be intensified by 'seiche pumping'. The results have a wide range of applications including transport of dissolved and suspended matter, assement of shoreline erosion, and exchange processes at the water-sediment boundary. In addition, knowledge of the spatial seiche pattern facilitates estimation of the hypothetical lake response to earthquakes in this seismically active region.

  9. Thermal structure of proglacial lakes in Patagonia

    Sugiyama, Shin; Minowa, Masahiro; Sakakibara, Daiki; Skvarca, Pedro; Sawagaki, Takanobu; Ohashi, Yoshihiko; Naito, Nozomu; Chikita, Kazuhisa


    Calving glaciers are rapidly retreating in many regions under the influence of ice-water interactions at the glacier front. In contrast to the numerous researches conducted on fjords in front of tidewater glaciers, very few studies have been reported on lakes in which freshwater calving glaciers terminate. To better understand ice-water interactions at the front of freshwater calving glaciers, we measured lakewater temperature, turbidity, and bathymetry near Glaciar Perito Moreno, Upsala, and Viedma, large calving glaciers of the Southern Patagonia Icefield. The thermal structures of these lakes were significantly different from those reported in glacial fjords. There was no indication of upwelling subglacial meltwater; instead, turbid and cold glacial water discharge filled the region near the lake bottom. This was because water density was controlled by suspended sediment concentrations rather than by water temperature. Near-surface wind-driven circulation reaches a depth of 180 m, forming a relatively warm isothermal layer (mean temperature of 5-6°C at Perito Moreno, 3-4°C at Upsala, and 6-7°C at Viedma), which should convey heat energy to the ice-water interface. However, the deeper part of the glacier front is in contact with stratified cold water, implying a limited amount of melting there. In the lake in front of Glaciar Viedma, the region deeper than 120 m was filled entirely with turbid and very cold water at pressure melting temperature. Our results revealed a previously unexplored thermal structure of proglacial lakes in Patagonia, suggesting its importance in the subaqueous melting of freshwater calving glaciers.

  10. Humanos salvajes y monos altruistas. Reflexiones sobre Darwin

    Martinez Contreras Jorge


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    Darwin propuso en 1871 que preferiría descender de un mono que de los “salvajes”. El mono es un babuino hamadryas que, en un relato de Brehm, salva a un infante de una jauría. Los “salvajes” son los fueguinos a los que visitó en los años 1830. ¿Por qué Darwin fue tan buen observador del comportamiento animal y por qué no dudo discernir en qué consistía la sociedad de cazadores-recolectores de los cuatro grupos de Tierra del Fuego?. Esto es lo que tratamos de dilucidar en este trabajo.


  11. Changes in lake level and trophy at Lake Vrana, a large karstic lake on the Island of Cres (Croatia, with respect to palaeoclimate and anthropogenic impacts during the last approx. 16,000 years

    Ante BARIĆ


    Full Text Available A multi-proxy approach study (cladocerans, diatoms, geochemistry, plant macrofossils, pollen, was performed on a sediment core from Lake Vrana (Vransko Jezero, a large and deep karstic lake on the northern Adriatic island of Cres, Croatia. Considerable lake-level changes occurred during the last approx. 16,000 years. The stratigraphic evidence suggests that periods of enhanced precipitation and the post-LGM rise in sea level were the main driving forces. The lake records indicate early human impacts. Sediment echo-sounding indicated that >25 m of lake sediments lies within the site, from which 5 m have been cored. Shallow lake stages occurred from 14.4 14C ky BP to early Holocene. Prior to Alleröd, interglacial sediments were redeposited, reflecting the influences of rising sea-level (forming a local groundwater barrier, a temporary increase in precipitation, and lake-level changes. There appears to be a hiatus in the sequence, for no sediments assignable to the Alleröd chronozone could be found. A discordance in the echo profile at the appropriate horizon in the sequence supports this interpretation. Groundwater level increased again at 10.6 ky BP (during Younger Dryas chronozone, a swamp vegetation formed, which gave way to a shallow lake. During the Preboreal chronozone, this freshwater lake persisted with fluctuating levels. The establishment and subsequent persistence of the present deep water lake at about 8.5 ky BP, correspond with findings of a pluvial period at the Dalmatian coast, which lasted from 8.4 to 6 ky BP. First human catchment disturbances were related to settlements of Neolithic or Bronze Age. The increase in summer drought, coupled with forest clearance during Illyrian times, are assumed to be responsible for the change towards present evergreen oak vegetation in the lake catchment. The intensification in land-use during Roman and post-Roman settlements caused a slight increase in the lake trophic level.

  12. Radiochronology of lake sediments

    Erten, H.N. [Bilkent Univ., Ankara (Turkey). Dept. of Chemistry


    Sediment cores from Lakes Zurich, Constance, from the Sea of Marmara and from southern Turkey, northern Cyprus and eastern Spain were dated using natural {sup 210}Pb, fallout {sup 137}Cs and cosmic-ray produced {sup 7}Be radionuclides. Constant activity regions in the uppermost sections of sediments from Lake Zurich and the Sea of Marmara were attributed to post-depositional mobility of {sup 210}Pb in the former case and to bioturbation in the latter. A serious discrepancy exists between the {sup 210}Pb dating of Sea of Marmara sediments and those obtained by organic carbon based methods. The elements Zn, Cu, P and Pb were enriched in the upper sections of the sediment cores corresponding to the last 200 years. The increased metallurgical activities as a result of reforms in the Ottoman Army during the 18th century could be the most likely cause. (Author).

  13. Energy-balance and melt contributions of supraglacial lakes, Langtang Khola, Nepal

    Miles, E. S.; Willis, I. C.; Pellicciotti, F.; Steiner, J. F.; Buri, P.; Arnold, N. S.


    As Himalayan debris-covered glaciers retreat and thin in response to climate warming, their long, low-gradient tongues generate substantial meltwater which often collects to form surface lakes. Supraglacial lakes on debris covered glaciers present a mechanism of atmosphere-glacier energy transfer that is poorly-studied, and only conceptually included in mass-balance studies. The ponded water can enhance energy transfer as compared to dry debris cover, while also acting as a reservoir of melt-available energy. Supraglacial lakes occur in association with debris-free ice cliffs, another poorly-constrained but critical component of glacier melt. Understanding the role of supraglacial lakes requires precise monitoring of lake volume, estimation of inlet and outlet flows, and consideration of the energy balance across three surfaces: atmosphere-lake, lake-ice, and lake-saturated debris layer. This research progresses previous modeling work on the energy and mass balance of such supraglacial lakes. Lakes were monitored during the monsoon of 2013 on Lirung Glacier in the Langtang Himal of Nepal with pressure transducers and temperature sensors, while UAV-derived DEMs were used to determine lake geometry. Lake albedo was measured to vary between 0.08 and 0.12, and a nearby on-glacier AWS was used to drive the energy balance. Results indicate that the lakes act as a significant recipient of energy, and suggest that lakes are an important part of an active supraglacial hydrologic system during the monsoon. Melt generated by the lake in contact with bare ice is calculated to be 3-5 cm/day, while energy conducted through saturated lake-bottom debris only resulted in 1-2 mm/day melt. The subaqueous melt rates are of similar magnitude to observed ice-cliff melt rates, allowing lake-cliff systems to persist. Energy leaving the lake system through englacial conduits may be the most important contribution to the glacier's mass balance, driving surface evolution to form new ice

  14. The influence of a lake-wetland complex on catchment nutrient flux and speciation

    Covino, T. P.; McGlynn, B. L.; Kalinin, A.


    reduced nitrogen (e.g., NH4-N) in piezometers located at the lake margins. These results suggest that lake-wetland complexes within stream networks can substantially alter the timing, magnitude, and form of fluvial nutrient flux and can even serve to reset catchment biogeochemical signatures over short (<1 km) spatial scales.

  15. 21 CFR 582.4101 - Diacetyl tartaric acid esters of mono- and diglycerides of edible fats or oils, or edible fat...


    ... 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, or...

  16. Not so Great Lakes?

    Showstack, Randy

    In 1965, Frank Sinatra won the Grammy Award for his album, "September of My Years;" "Early Bird," the first commercial communications satellite, was launched; and Dr. Martin Luther King, Jr. was arrested in Selma, Alabama, during demonstrations against voter-registration rules.The year 1965 was also the last time water levels in the U.S. Great Lakes were as low as they are now.

  17. Great Lakes Energy Institute

    Alexander, J. Iwan [Case Western Reserve Univ., Cleveland, OH (United States)


    The vision of the Great Lakes Energy Institute is to enable the transition to advanced, sustainable energy generation, storage, distribution and utilization through coordinated research, development, and education. The Institute will place emphasis on translating leading edge research into next generation energy technology. The Institute’s research thrusts focus on coordinated research in decentralized power generation devices (e.g. fuel cells, wind turbines, solar photovoltaic devices), management of electrical power transmission and distribution, energy storage, and energy efficiency.

  18. Audubon National Wildlife Refuge, Lake Nettie National Wildlife Refuge, Camp Lake Easement Refuge, Wintering River Easement Refuge, Cottonwood Lake Easement Refuge, Sheyenne Lake Easement Refuge : Narrative report : 1969

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Audubon National Wildlife Refuge (including Lake Nettie National Wildlife Refuge, Camp Lake Easement Refuge, Cottonwood Lake...

  19. Bear Lake-Minidoka - Phragmites Control

    US Fish and Wildlife Service, Department of the Interior — Bear Lake: Phragmites patches were sprayed on the refuge & north of the lake proper. Minidoka: patches along the Snake River & Lake Walcott were treated with...

  20. Environmental Monitoring, Water Quality - Lakes Assessments - Attaining

    NSGIC Education | GIS Inventory — This layer shows only attaining lakes of the Integrated List. The Lakes Integrated List represents lake assessments in an integrated format for the Clean Water Act...

  1. Opportunistic fungi in lake water and fungal infections in associated human population in Dal Lake, Kashmir.

    Bandh, Suhaib A; Kamili, Azra N; Ganai, Bashir A; Lone, Bashir A


    Natural habitats of opportunistic fungal pathogens are outside of the host; therefore, it is critically important to understand their ecology and routes of transmission. In this study, we investigated the presence of human pathogenic opportunistic fungi in lake water and incidence of fungal infections in associated population in Kashmir, India. Six hundred forty water samples were taken on seasonal basis from a wide network of sampling stations of the lake for an extended period of two years for screening their occurrence. The samples were inoculated onto rose bengal agar, malt extract agar, potato dextrose agar and other specified culture media supplemented with Chloramphenicol and Streptomycin followed by incubation at 37 °C. All the samples were positive for fungi, which were later identified by sequencing the rDNA internal transcribed spacer region aided by classical morphological culture techniques and physiological profiling. The whole process led to the isolation of sixteen species of opportunistic fungal pathogens belonging to genus Aspergillus, Candida, Penicillium, Cryptococcus, Fusarium, Rhizopus and Mucor in decreasing order of prevalence. Furthermore, 20% population (n = 384) of Dal inhabitants was examined for possible fungal infections and it was observed that only 8.07% individuals were positive for fungal infections with 4.68% skin infection cases, 2.34% onychomycosis cases and 1.04% candidiasis cases. Scrapings from onychomycosis and candidiasis patients showed the presence of Aversicolor and Calbicans respectively, resembling exactly the strains isolated from the lake water. However, the skin infection was because of a dermatophyte not isolated for the lake water. Higher prevalence of infection (6.77%) was seen in people using lake water followed by a positive prevalence of 1.30% using tap water. The results of present study suggest that the lake inhabitants are at a greater risk of getting life threatening fungal diseases which may lead to

  2. Circumpolar mapping of ground-fast lake ice

    Bartsch, Annett; Pointner, Georg; Leibman, Marina O.; Dvornikov, Yuri A.; Khomutov, Artem V.; Trofaier, Anna M.


    depth measurements from several sites suggest that the used method yields the potential to utilize ground-fast lake ice information over larger areas with respect to landscape development, but results need to be treated with care, specifically for larger lakes and along river courses.

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

    Kim, Seung-Kyu; Kannan, Kurunthachalam


    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.

  4. Testing the spatial and temporal framework of speciation in an ancient lake species flock: the leech genus Dina (Hirudinea: Erpobdellidae in Lake Ohrid

    T. Wilke


    Full Text Available Ancient Lake Ohrid on the Balkan Peninsula is considered to be the oldest ancient lake in Europe with a suggested Plio-Pleistocene age. Its exact geological age, however, remains unknown. Therefore, molecular clock data of Lake Ohrid biota may serve as an independent constraint of available geological data, and may thus also help to refine age estimates. Such evolutionary data may also help unravel potential biotic and abiotic factors that promote speciation events. Here, mitochondrial sequencing data of one of the largest groups of endemic taxa in Lake Ohrid, the leech genus Dina, is used to test whether it represents an ancient lake species flock, to study the role of horizontal and vertical barriers in Lake Ohrid for evolutionary events, to estimate the onset of intralacustrine diversification in this group based on molecular clock analyses, and to compare this data with data from other endemic species for providing an approximate time frame for the origin of Lake Ohrid. Based on the criteria speciosity, monophyly and endemicity, it can be concluded that Lake Ohrid Dina, indeed, represents an ancient lake species flock. Lineage sorting of its species, however, does not seem to be complete. Analyses of population structures of Dina spp. in the Ohrid watershed indicate a horizontal zonation of haplotypes from spring and lake populations, corroborating the role of lake-side springs, particularly the southern feeder springs, for evolutionary processes in endemic Ohrid taxa. Vertical differentiation of lake taxa, however, appears to be limited, though differences between populations from the littoral and the profundal are apparent. Molecular clock analyses indicate that the most recent common ancestor of extant species of this flock is approximately 1.99±0.83 Ma old, whereas the split of the Lake Ohrid Dina flock from a potential sister taxon outside the lake is estimated at 8.30±3.60 Ma. Comparisons with other groups of endemic Ohrid species

  5. Algae Bloom in a Lake

    David Sanabria


    Full Text Available The objective of this paper is to determine the likelihood of an algae bloom in a particular lake located in upstate New York. The growth of algae in this lake is caused by a high concentration of phosphorous that diffuses to the surface of the lake. Our calculations, based on Fick's Law, are used to create a mathematical model of the driving force of diffusion for phosphorous. Empirical observations are also used to predict whether the concentration of phosphorous will diffuse to the surface of this lake within a specified time and under specified conditions.

  6. Great Lakes' regional climate regimes

    Kravtsov, Sergey; Sugiyama, Noriyuki; Roebber, Paul


    We simulate the seasonal cycle of the Great Lakes' water temperature and lake ice using an idealized coupled lake-atmosphere-ice model. Under identical seasonally varying boundary conditions, this model exhibits more than one seasonally varying equilibrium solutions, which we associate with distinct regional climate regimes. Colder/warmer regimes are characterized by abundant/scarce amounts of wintertime ice and cooler/warmer summer temperatures, respectively. These regimes are also evident in the observations of the Great Lakes' climate variability over recent few decades, and are found to be most pronounced for Lake Superior, the deepest of the Great Lakes, consistent with model predictions. Multiple climate regimes of the Great Lakes also play a crucial role in the accelerated warming of the lakes relative to the surrounding land regions in response to larger-scale global warming. We discuss the physical origin and characteristics of multiple climate regimes over the lakes, as well as their implications for a longer-term regional climate variability.

  7. Limited Regulation of Lake Erie.


    Ontario,, Cedar Point in Ohio, Presque Isle in Pennsylvania and Hamlin in New York. Recreational boating is a significant activity on Lake Erie . Along...RD-Al47 936 LIMITED REGULATION OF LAKE ERIE (U) INTERNATIONAL LAKE i/i ERIE REGULATION STUDY BOARD NOV 83 UNCLASSIFIED F/G 13/2 N lhhhhh..hEmhhI...o lake Erie ’Governmen of 4,- % * L CTE " 84100400 .- Canad Unite Stte INTRNAIONL OIN COMISIO 4WD’ This document hais been ow for public rleoe and so


    Petre GÂŞTESCU


    Full Text Available The article offers a synthesis of the lakes of Romania. We addressed the following questions: genetic types of lakes, geographical distribution and their use in various fields of activities. Thus, in the territory of Romania is a large genetic diversity of lakes distributed on all major forms of relief and recovery in many economic areas. Romania is particularly present fluvial lakes, glacial lakes and anthropogenic lakes (especially reservoirs.

  9. Glacial lakes Buni and Jezerce: Albania

    Milivojević Milovan; Kovačević-Majkić Jelena


    The paper presents glacial lakes and glacial relief forms at the foothill of the peak Maja Jezerce in Mt. Prokletije in Albania, near the border with Montenegro. The group of lakes Buni and Jezerce, which consists of six lakes and which genetically belongs to glacial-erosional lakes, is analyzed. Lakes are situated at the cirque bottom, between the moraines and limestone ridges. Except presented morphometric characteristics of lake basins, data about cirque are given, as well as the reconstru...


    Petre GÂŞTESCU


    The article offers a synthesis of the lakes of Romania. We addressed the following questions: genetic types of lakes, geographical distribution and their use in various fields of activities. Thus, in the territory of Romania is a large genetic diversity of lakes distributed on all major forms of relief and recovery in many economic areas. Romania is particularly present fluvial lakes, glacial lakes and anthropogenic lakes (especially reservoirs).

  11. Sources of methane to an Arctic lake in Alaska: An isotopic investigation

    Lecher, Alanna L.; Chuang, Pei-Chuan; Singleton, Michael; Paytan, Adina


    Sources of dissolved methane (CH4) at Toolik Lake, Alaska, include both diffusion from lake sediments and groundwater entering the lake from its perimeter. Here we use hydrogen and oxygen isotopes in water (H2O), carbon and hydrogen isotopes in CH4, and carbon isotopes in dissolved inorganic carbon (DIC) to calculate the relative importance of lake sediment and groundwater discharge as sources of dissolved CH4 to Toolik Lake. We also resolve the relative importance of the source contribution spatially within the lake and determine the processes controlling CH4 concentrations in groundwater surrounding the lake. Our findings, from a mixing model based on isotopes in CH4, suggest that groundwater is a more important source of CH4 at the perimeter of the lake where the water-to-air flux is high. Additionally, we find on the local scale that high groundwater methane concentrations may be better linked to areas around the lake where rain is the dominant source of water to the active layer, indicating that changes in precipitation and active layer thaw depth will impact methane concentrations in the active layer and, ultimately, the groundwater associated flux to Toolik Lake.

  12. A preliminary evaluation of lake morphometric traits influence on the maximum growing depth of macrophytes

    Mattia M. Azzella


    Full Text Available Underwater light regime is widely considered the principal determinant of aquatic plant depth distribution. The majority of previous studies dealing with macrophytes in lakes have singled out Secchi disk transparency (SD values as the key empirical proxy to explain the maximum depth of macrophyte colonization (Zc. Few studies have investigated the role played by lake morphometry in structuring macrophyte beds. Using a balanced dataset including 20 Italian lakes (10 shallow and 10 deep lakes, we analysed transparency and lake morphometric traits to investigate their possible effects on Zc. Our results demonstrate that lake area plays a significant role, and confirm a direct influence of SD values on Zc. Considering lakes with an equal degree of transparency, smaller lakes may yield a lower Zc than larger ones. Morphology has a great influence on lake ecological characteristics especially on water thermal conditions and mixing depth. Based on our data, we argue that the thermal stratification plays a non negligible role in explaining macrophytes zonation, due to its influence on macrophytes life cycles and phytoplankton vertical distribution. Therefore, the present data suggest the need to enhance and refine our knowledge about the relationship between aquatic plants distribution and lake thermal conditions to better model the response of macrophytes to climate change and eutrophication.

  13. Phytoplankton diversity in the middle Rio Doce lake system of southeastern Brazil

    Cristiane Freitas de Azevedo Barros


    Full Text Available This study presents results of the inventory of algal flora conducted between August 2007 and May 2008 in 18 lakes of the middle Rio Doce lake system, most of which is in the state of Minas Gerais, Brazil. We recorded 481 taxa, increasing the known total phytoplankton diversity of the region (gamma diversity by 80%. The following classes were represented: Zygnematophyceae (171 taxa, Cyanobacteria (101, Chlorophyceae (71, Bacillariophyceae (42, Euglenophyceae (43, Trebouxiophyceae (24, Dinophyceae (8, Xanthophyceae (8, Chrysophyceae (6, Cryptophyceae (6 and Oedogoniophyceae (1. We identified 221 taxa that were rare (restricted to one or two lakes, and 101 that were considered representative (present in at least nine lakes. Botryococcus braunii, Elakatothrix genevensis, Planktolyngbya limnetica, Peridinium pusillum, Trachelomonas volvocina, Cosmarium contractum, Staurastrum forficulatum, Staurastrum leptocladum, Staurastrum rotula, and Staurodesmus dejectus were present in all lakes. Richness varied from 95 taxa (in Lake Gambazinho to 168 taxa (in Lake Palmeirinha. Jaccard indices were low, and the highest similarities between lakes were 53% (Ferrugem/Ferruginha, 47% (Central/Almécega and 46% (Águas Claras/Palmeirinha, demonstrating high environmental and biotic dissimilarities between lakes. Geographic distance was not significantly associated with floristic similarity, suggesting that local factors are more important than are regional ones in shaping the phytoplankton composition of lakes.

  14. Phytoplankton diversity in relation to different weather conditions in two urban made lakes

    Munay Abdulqadir Omar


    Full Text Available Many scientists have reported that global warming have significant impact on phytoplankton community, however, the impact of global warming on phytoplankton communities in suburban made lake is less understood. Therefor the objective of this study are to observe the effect of variable weather conditions on the diversity and succession of phytoplankton in mesotrophic lake (Seri Serdang and oligotrophic lake (Engineering Faculty Lake. Samples were collected from surface water and species diversity (Shannon Weaver Diversity Index was calculated. Daily weather and rain fall were recorded. A total of 65 species from five divisions (Chlorophyta, Euglenophyta, Cyanophyta, Bacillariophyta and Dinophyta and 52 species belonging to six divisions (Chlorophyta, Cyanophyta, Bacillariophyta, Euglenophyta, Cryptophyta & Charophyta were recorded from Engineering Faculty Lake and Seri Serdang Lake respectively. Division of Chlorophyta was found most dominant in both lakes during all the weeks (67%. The most dominant species in Faculty Engineering Lake was Microcystis aeruginosa during all weather conditions. Whereas, the most dominant species in Seri Serdang Lake during all weather conditions were Chlamydomonas reinhardtii, Planktothrix agardhii. The phytoplankton density was low during dry weather conditions for both lakes. The present finding suggested noticeable correlation between weather changes to the alteration of population density of phytoplankton.

  15. Parasites pitched against nature: Pitch Lake water protects guppies (Poecilia reticulata) from microbial and gyrodactylid infections.

    Schelkle, Bettina; Mohammed, Ryan S; Coogan, Michael P; McMullan, Mark; Gillingham, Emma L; VAN Oosterhout, Cock; Cable, Joanne


    SUMMARY The enemy release hypothesis proposes that in parasite depleted habitats, populations will experience relaxed selection and become more susceptible (or less tolerant) to pathogenic infections. Here, we focus on a population of guppies (Poecilia reticulata) that are found in an extreme environment (the Pitch Lake, Trinidad) and examine whether this habitat represents a refuge from parasites. We investigated the efficacy of pitch in preventing microbial infections in Pitch Lake guppies, by exposing them to dechlorinated water, and reducing gyrodactylid infections on non-Pitch Lake guppies by transferring them to Pitch Lake water. We show that (i) natural prevalence of ectoparasites in the Pitch Lake is low compared to reference populations, (ii) Pitch Lake guppies transferred into aquarium water develop microbial infections, and (iii) experimentally infected guppies are cured of their gyrodactylid infections both by natural Pitch Lake water and by dechlorinated water containing solid pitch. These results indicate a role for Pitch Lake water in the defence of guppies from their parasites and suggest that Pitch Lake guppies might have undergone enemy release in this extreme environment. The Pitch Lake provides an ideal ecosystem for studies on immune gene evolution in the absence of parasites and long-term evolutionary implications of hydrocarbon pollution for vertebrates.

  16. 1. Mono([8]annulene)Uranium(4) half-sandwich complexes, 2. Novel syntheses of symmetrically substituted cyclooctatetetraenes

    Boussie, T.R.


    A reproducible, high-yield synthesis of mono([8]annulene)uranium(4)dichloride (1) is reported, along with the X-ray crystal structural of the bis(pyridine) adduct. Metathesis reactions of the half-sandwich complex 1 with a variety of simple alkyl and alkoxy reagents failed to generate any isolable mono-ring complexes. Reactions of 1 with polydentate, delocalized anions did produce stable derivatives, including mono([8]annulene)uranium(4)bis(acetylacetonate) (4). An X-ray crystal structure of 4 is reported.

  17. 1. Mono((8)annulene)Uranium(4) half-sandwich complexes, 2. Novel syntheses of symmetrically substituted cyclooctatetetraenes

    Boussie, T.R.


    A reproducible, high-yield synthesis of mono((8)annulene)uranium(4)dichloride (1) is reported, along with the X-ray crystal structural of the bis(pyridine) adduct. Metathesis reactions of the half-sandwich complex 1 with a variety of simple alkyl and alkoxy reagents failed to generate any isolable mono-ring complexes. Reactions of 1 with polydentate, delocalized anions did produce stable derivatives, including mono((8)annulene)uranium(4)bis(acetylacetonate) (4). An X-ray crystal structure of 4 is reported.

  18. Lake Charles CCS Project

    Leib, Thomas [Leucadia Energy, LLC, Salt Lake City, UT (United States); Cole, Dan [Denbury Onshore, LLC, Plano, TX (United States)


    In late September 2014 development of the Lake Charles Clean Energy (LCCE) Plant was abandoned resulting in termination of Lake Charles Carbon Capture and Sequestration (CCS) Project which was a subset the LCCE Plant. As a result, the project was only funded through Phase 2A (Design) and did not enter Phase 2B (Construction) or Phase 2C (Operations). This report was prepared relying on information prepared and provided by engineering companies which were engaged by Leucadia Energy, LLC to prepare or review Front End Engineering and Design (FEED) for the Lake Charles Clean Energy Project, which includes the Carbon Capture and Sequestration (CCS) Project in Lake Charles, Louisiana. The Lake Charles Carbon Capture and Sequestration (CCS) Project was to be a large-scale industrial CCS project intended to demonstrate advanced technologies that capture and sequester carbon dioxide (CO2) emissions from industrial sources into underground formations. The Scope of work was divided into two discrete sections; 1) Capture and Compression prepared by the Recipient Leucadia Energy, LLC, and 2) Transport and Sequestration prepared by sub-Recipient Denbury Onshore, LLC. Capture and Compression-The Lake Charles CCS Project Final Technical Report describes the systems and equipment that would be necessary to capture CO2 generated in a large industrial gasification process and sequester the CO2 into underground formations. The purpose of each system is defined along with a description of its equipment and operation. Criteria for selection of major equipment are provided and ancillary utilities necessary for safe and reliable operation in compliance with environmental regulations are described. Construction considerations are described including a general arrangement of the CCS process units within the overall gasification project. A cost estimate is provided, delineated by system area with cost breakdown showing equipment, piping and materials

  19. An Integrated Approach for Understanding Anthropogenic and Climatic Impacts on Lakes: A Case study from Lake Iznik, Turkey

    Derin, Y.; Milewski, A.; Fryar, A. E.; Schroeder, P.


    gauges (1990 water level: 8386cm; 2010 water level: 8000cm) and a decline in surface area extent as seen in the Landsat data is mostly attributed to changes in landuse practices. Rainfall has increased during this same period suggesting the decline in water quantity is mostly a result of water use practices (e.g. overpumping, increased irrigation). The drop in lake level combined with changes in land management practices has resulted in decreased water quality. Ongoing research is being conducted to predict the amount of flow and required change in land use needed to restore the lake to mesotrophic conditions using the constructed hydrologic model. Results show the potential for using integrated approaches to better understand, differentiate, and mitigate anthropogenic and climate impacts on lakes around the world.


    lake's geological history of having marine inputs from the Red Sea (Gionfiantini et al., 1973). Unlike the other ... area) at the shore where one of the hot springs joins the lake. It is not known ... that goes to the Red Sea port of Assab. One of the ...

  1. Late Quaternary palaeoenvironmental reconstruction from Lakes Ohrid and Prespa (Macedonia/Albania border using stable isotopes

    M. J. Leng


    Full Text Available Here we present stable isotope data from three sediment records from lakes that lie along the Macedonian-Albanian border (Lake Prespa: 1 core, and Lake Ohrid: 2 cores. The records only overlap for the last 40 kyr, although the longest record contains the MIS 5/6 transition (Lake Ohrid. The sedimentary characteristics of both lakes differ significantly between the glacial and interglacial phases. At the end of MIS 6 Lake Ohrid's water level was low (high δ18Ocalcite and, although productivity was increasing (high calcite content, the carbon supply was mainly from inorganic catchment rock sources (high δ13Ccarb. During the last interglacial, calcite and TOC production and preservation increased, progressively lower δ18Ocalcite suggest increase in humidity and lake levels till around 115 ka. During ca. 80 ka to 11 ka the lake records suggest cold conditions as indicated by negligible calcite precipitation and low organic matter content. In Lake Ohrid δ13Corg are complacent, in contrast Lake Prespa shows consistently higher δ13Corg suggesting a low oxidation of 13C-depleted organic matter in agreement with a general deterioration of climate conditions during the glacial. From 15 ka to the onset of the Holocene, calcite and TOC begin to increase, suggesting lake levels were probably low (high δ18Ocalcite. In the Holocene (11 ka to present enhanced productivity is manifested by high calcite and organic matter content. All three cores show an early Holocene characterised by low δ18Ocalcite, apart from the very early Holocene phase in Prespa where the lowest δ18Ocalcite occurs at ca. 7.5 ka, suggesting a phase of higher lake level only in (the more sensitive Lake Prespa. From 6 ka δ18Ocalcite suggest progressive aridification, in agreement

  2. Late Quaternary palaeoenvironmental reconstruction from Lakes Ohrid and Prespa (Macedonia/Albania border using stable isotopes

    M. J. Leng


    Full Text Available Here we present stable isotope data from three sediment records from lakes that lie along the Macedonian-Albanian border (Lake Prespa: 1 core, and Lake Ohrid: 2 cores. The records only overlap for the last 40 kyr, although the longest record contains the MIS 5/6 transition (Lake Ohrid. The sedimentary characteristics of both lakes differ significantly between the glacial and interglacial phases. At the end of MIS 6 Lake Ohrid's water level was low (high δ18Ocalcite and, although productivity was increasing (high calcite content, the carbon supply was mainly from inorganic catchment rock sources (high δ13Ccarb. During the last interglacial, calcite and TOC production and preservation increased, progressively lower δ18Ocalcite suggest increase in humidity and lake levels until around 115 ka. During ca. 80 ka to 11 ka the lake records suggest cold conditions as indicated by negligible calcite precipitation and low organic matter content. In Lake Ohrid, δ13Corg are complacent; in contrast, Lake Prespa shows consistently higher δ13Corg suggesting a low oxidation of 13C-depleted organic matter in agreement with a general deterioration of climate conditions during the glacial. From 15 ka to the onset of the Holocene, calcite and TOC begin to increase, suggesting lake levels were probably low (high δ18Ocalcite. In the Holocene (11 ka to present enhanced productivity is manifested by high calcite and organic matter content. All three cores show an early Holocene characterised by low δ18Ocalcite, apart from the very early Holocene phase in Prespa where the lowest δ18Ocalcite occurs at ca. 7.5 ka, suggesting a phase of higher lake level only in (the more sensitive Lake Prespa. From 6 ka, δ18Ocalcite suggest progressive aridification, in

  3. Littoral zones as sources of biodegradable dissolved organic carbon in lakes

    Stets, E.G.; Cotner, J.B.


    A survey of 12 lakes in Minnesota, USA, was conducted to examine the factors controlling variability in biodegradable dissolved organic carbon (BDOC) concentration. The principal question addressed was whether BDOC concentration was more strongly related to lake trophic status or morphometric parameters. BDOC concentration was determined by incubating filtered lake water for a period of 15 months and fitting an exponential decay curve to measured DOC concentrations. BDOC concentrations varied from 73 to 427 mmol C.L-1 and composed 15%-63% of the total DOC pool. There were no significant correlations between BDOC and measures of lake trophic status. Instead, BDOC was most closely associated with the percentage of lake area covered by littoral zone, suggesting a significant source of BDOC from aquatic macrophytes and lake surface sediments. ?? 2008 NRC.

  4. Brief Communication "Expansion of meltwater lakes on the Greenland Ice Sheet"

    M. R. van den Broeke


    Full Text Available Forty years of satellite imagery reveal that meltwater lakes on the margin of the Greenland Ice Sheet have expanded substantially inland to higher elevations with warming. These lakes are important because they provide a mechanism for bringing water to the ice bed, causing sliding. Inland expansion of lakes could accelerate ice flow by bringing water to previously frozen bed, potentially increasing future rates of mass loss. Increasing lake elevations closely follow the rise of the mass balance equilibrium line over much of the ice sheet, suggesting no physical limit on lake expansion. Data are not yet available to detect a corresponding change in ice flow, and the potential effects of lake expansion on ice sheet dynamics are not included in ice sheet models.

  5. Subaqueous geology and a filling model for Crater Lake, Oregon

    Nathenson, M.; Bacon, C.R.; Ramsey, D.W.


    Results of a detailed bathymetric survey of Crater Lake conducted in 2000, combined with previous results of submersible and dredge sampling, form the basis for a geologic map of the lake floor and a model for the filling of Crater Lake with water. The most prominent landforms beneath the surface of Crater Lake are andesite volcanoes that were active as the lake was filling with water, following caldera collapse during the climactic eruption of Mount Mazama 7700 cal. yr B.P. The Wizard Island volcano is the largest and probably was active longest, ceasing eruptions when the lake was 80 m lower than present. East of Wizard Island is the central platform volcano and related lava flow fields on the caldera floor. Merriam Cone is a symmetrical andesitic volcano that apparently was constructed subaqueously during the same period as the Wizard Island and central platform volcanoes. The youngest postcaldera volcanic feature is a small rhyodacite dome on the east flank of the Wizard Island edifice that dates from 4800 cal. yr B.P. The bathymetry also yields information on bedrock outcrops and talus/debris slopes of the caldera walls. Gravity flows transport sediment from wall sources to the deep basins of the lake. Several debris-avalanche deposits, containing blocks up to 280 m long, are present on the caldera floor and occur below major embayments in the caldera walls. Geothermal phenomena on the lake floor are bacterial mats, pools of solute-rich warm water, and fossil subaqueous hot spring deposits. Lake level is maintained by a balance between precipitation and inflow versus evaporation and leakage. High-resolution bathymetry reveals a series of up to nine drowned beaches in the upper 30 m of the lake that we propose reflect stillstands subsequent to filling of Crater Lake. A prominent wave-cut platform between 4 m depth and present lake level that commonly is up to 40 m wide suggests that the surface of Crater Lake has been at this elevation for a very long time

  6. Geo- and Biogeochemical Processes in a Heliothermal Hypersaline Lake

    Zachara, John M.; Moran, James J.; Resch, Charles T.; Lindemann, Stephen R.; Felmy, Andrew R.; Bowden, Mark E.; Cory, Alexandra B.; Fredrickson, Jim K.


    exchange, and lower winter lake temperatures. Solubility calculations indicated seasonal biogenic and thermogenic aragonite precipitation in the upper and lower mixolimnion, but the absence of calcareous sediments at depth suggested dissolution and recycling during winter months. Carbon concentrations were high in Hot Lake (e.g., 0 to 450 mg/L for both DOC and DIC) and increased with depth. DIC concentrations were variable and influenced by calcium carbonate precipitation, but DOC concentrations remained constant except in the monimolimnion where mass loss by anaerobic microbial processes was implied. Biogenic reduced solutes originating in monimolimnion (H2S and CH4) appeared to be biologically oxidized in the metalimnion as they were not observed in more shallow lake waters. Multi-year solute inventory calculations indicated that Hot Lake is a stable, albeit seasonally and annually dynamic feature, with inorganic solutes cycled between lake waters and sediments depending on annual recharge, temperature, and lake water dilution state. Hot Lake with its extreme geochemical and thermal regime functions as analogue of early earth and extraterrestrial life environments.

  7. Design and synthesis of potent inhibitors of the mono(ADP-ribosyl)transferase, PARP14.

    Upton, Kristen; Meyers, Matthew; Thorsell, Ann-Gerd; Karlberg, Tobias; Holechek, Jacob; Lease, Robert; Schey, Garrett; Wolf, Emily; Lucente, Adrianna; Schüler, Herwig; Ferraris, Dana


    A series of (Z)-4-(3-carbamoylphenylamino)-4-oxobut-2-enyl amides were synthesized and tested for their ability to inhibit the mono-(ADP-ribosyl)transferase, PARP14 (a.k.a. BAL-2; ARTD-8). Two synthetic routes were established for this series and several compounds were identified as sub-micromolar inhibitors of PARP14, the most potent of which was compound 4t, IC50=160nM. Furthermore, profiling other members of this series identified compounds with >20-fold selectivity over PARP5a/TNKS1, and modest selectivity over PARP10, a closely related mono-(ADP-ribosyl)transferase. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Literature review on cyclic lateral loading effects of mono-bucket foundations

    Kapitanov, Lachezar Rosenov; Duroska, Peter; Garcia, Cesar Antonio Garcia


    The renewable offshore energy sector is currently growing rapidly and there is a vast interest in optimization of the design procedures for the offshores wind turbines. Mono-Bucket can be a breakthrough in the sphere of offshore wind turbines foundations due to its lightness and fast installation...... and consequently cost-effectiveness compared to other common solutions. The long-term cyclic loading can cause degradation of soil-bucket system stiffness, which yields into accumulated and permanent deformations. Despite of the advantages, there is no standard procedure to design the foundation especially...... for assessing the accumulated deformations under environmental longterm loading. However, numerical and semi-empirical methods already used for offshore foundations can be adopted to take into account the effect of cyclic loading on Mono-Buckets. Among them, load-displacement techniques as cyclic p-y curves...

  9. Synergistic extraction of praseodymium with 2-ethylhexyl phosphonic acid mono-2-ethylhexyl ester and 8-Hydroxyquinoline

    ZHANG Qian; WU Dong-bei; BAO Bo-rong


    The synergistic extraction of Pr3+ from hydrochloric medium using mixture of 2-ethylhexyl phosphonic acid mono-2-ethylhexyl ester (P507, HL) and 8-Hydroxyquinoline (HQ) in heptane was investigated. The effect of equilibrium of aqueous acidity on extraction of Pr3+ was discussed. The effect of extractant concentraction, different diluents, equilibrium time and acetate ion concentration on extraction reaction were also studied. With a method of double-logarithmic slope, composition of the extracted species on 2-ethylhexyl phosphonic acid mono-2-ethylhexyl ester and 8-Hydroxyquinolinc was derived. The result shows that the synergistic extraction system not only overcomes emulsification of 8-Hydroxyquinoline, but also shows perfect capacity of synergistic extraction. The largest synergistic enhancement factor can be calculated to be 5.49 at pH 3.6 for Pr3+.

  10. Mono-layer BC2 a high capacity anode material for Li-ion batteries

    Hardikar, Rahul; Samanta, Atanu; Han, Sang Soo; Lee, Kwang-Ryeol; Singh, Abhishek


    Mono-layer of graphene with high surface area compared to the bulk graphite phase, shows less Li uptake. The Li activity or kinetics can be modified via defects and/or substitutional doping. Boron and Nitrogen are the best known dopants for carbonaceous anode materials. In particular, boron doped graphene shows higher capacity and better Li adsorption compared to Nitrogen doped graphene. Here, using first principles density functional theory calculations, we study the spectrum of boron carbide (BCx) mono-layer phases in order to estimate the maximum gravimetric capacity that can be achieved by substitutional doping in graphene. Our results show that uniformly boron doped BC2 phase shows a high capacity of? 1400 mAh/g, much higher than previously reported capacity of BC3. Supported by Korea Institute of Science and Technology.

  11. Nonlinear Optical Properties of Novel Mono-O-Hydroxy Bidentate Schiff Base: Quantum Chemical Calculations

    N. S. Labidi


    Full Text Available The semiempirical AM1 SCF method is used to study the first static hyperpolarizabilities β of some novel mono-O-Hydroxy bidentate Schiff base in which electron donating (D and electron accepting (A groups were introduced on either side of the Schiff base ring system. Geometries of all molecules were optimized at the semiempirical AM1. The first static hyperpolarizabilities of these molecules were calculated using Hyperchem package. To understand this phenomenon in the context of molecular orbital picture, we examined the molecular HOMO and molecular LUMO generated via Hyperchem. The study reveals that the mono-O-Hydroxy bidentate Schiff bases have large β values and hence in general may have potential applications in the development of nonlinear optical materials.

  12. Resurrecting an unsalvageable lower incisor with a mono-block approach

    Jain, Rachit; Thomas, Manuel S.; Yadav, Amit


    Contemporary techniques, as well as the availability of bioactive and adhesive materials in endodontics, have helped revivifying teeth that were deemed hopeless. These newer materials and techniques would enable the clinician: (a) to predictably stop microbial activity (b) to achieve a total corono-apical fluid tight seal and (c) to strengthen mutilated teeth by obtaining intra-radicular reinforcement through mono-block effect. This case report demonstrates the successful treatment of a mutilated anterior tooth with the use of bioactive and adhesive materials to obtain a total seal and mono-block effect. This article also shows the use of a simple method in the placement of root filling cement into the root canal. PMID:26430310

  13. Couple Control Model Implementation on Antagonistic Mono- and Bi-Articular Actuators

    Prattico, Flavio; Yamamoto, Shin-ichiroh


    Recently, robot assisted therapy devices are increasingly used for spinal cord injury (SCI) rehabilitation in assisting handicapped patients to regain their impaired movements. Assistive robotic systems may not be able to cure or fully compensate impairments, but it should be able to assist certain impaired functions and ease movements. In this study, a couple control model for lower-limb orthosis of a body weight support gait training system is proposed. The developed leg orthosis implements the use of pneumatic artificial muscle as an actuation system. The pneumatic muscle was arranged antagonistically to form two pair of mono-articular muscles (i.e., hip and knee joints), and a pair of bi-articular actuators (i.e., rectus femoris and hamstring). The results of the proposed couple control model showed that, it was able to simultaneously control the antagonistic mono- and bi-articular actuators and sufficiently performed walking motion of the leg orthosis.

  14. Rotavirus infection in children: mono-and combines forms, especially clinics and course

    N. B. Denisyuk


    Full Text Available Analyzed 74 case histories of children under one year with rotavirus infection. The most commonly detected rotavirus gastroenteritis in the form of mono-and combined forms. Mono-infection in 78.3% of cases occurred in the moderate form with a leading syndrome in the form of gastroenteritis, severe dehydration proceeded with symptoms of varying severity. Mixed variants in 98.7% of cases are in the unfavorable premorbid background, in 42.8% of children were registered in the severe forms, and children younger than 6 months were erased within. The diagnosis of intestinal infection was confirmed by PCR, bacteriological and immunological methods.

  15. Detection and Quantification of Crack in Composite Mono Leaf Spring by Vibration Parameters

    Jamadar, Nagendra Iranna; Kivade, Sangshetty Bheemanna; Pedada, Sudhakara Rao


    Automobile industries focus for the components alternative to conventional materials with composites. There is high demand for enhanced performance and light weight. The emphasis is given for composite mono leaf spring as potential item as it is made up of glass fibre reinforced plastics despite they are sensitive to damages such as crack, delamination, de-bonding etc., occurred during either manufacturing or in service condition. These damages grow in progression and results in catastrophic failure. This work aims to deal with structural health monitoring to study and analyse the damage levels in composite mono leaf spring such as detection, location and quantification of damage. An experimental investigation has been carried out to evaluate presence and severity of damage by vibration parameters and validated with simulation.

  16. Resurrecting an unsalvageable lower incisor with a mono-block approach

    Rachit Jain


    Full Text Available Contemporary techniques, as well as the availability of bioactive and adhesive materials in endodontics, have helped revivifying teeth that were deemed hopeless. These newer materials and techniques would enable the clinician: (a to predictably stop microbial activity (b to achieve a total corono-apical fluid tight seal and (c to strengthen mutilated teeth by obtaining intra-radicular reinforcement through mono-block effect. This case report demonstrates the successful treatment of a mutilated anterior tooth with the use of bioactive and adhesive materials to obtain a total seal and mono-block effect. This article also shows the use of a simple method in the placement of root filling cement into the root canal.

  17. The origin of oriented lakes in the Andean foreland, Parque Nacional Torres del Paine (Chilean Patagonia)

    Gonzales, Joseph; Aydin, Atilla


    The Parque Nacional Torres Del Paine and surrounding area in the Magallanes foreland basin in Chilean Patagonia is the site for numerous lakes fed by glaciers and rivers in the Andean highlands to the west. The lakes are elongate and have conspicuously systematic orientations. We hypothesize that the origin of the oriented lakes lies in the fault system, composed of a right-lateral strike-slip fault set oriented 58° from north, a left-lateral strike-slip set oriented 87°, and a thrust fault set oriented 167°, that exists within the underlying rocks. To test this hypothesis quantitatively, we determined the shape and orientation of the lakes by fitting each lake with an ellipse of appropriate aspect ratio, and later with multiple ellipses consistent with the composite geometry of some lakes. We then examined the faults in the area in terms of their kinematics, orientation and distribution. The distribution of lake orientations showed three distinct groups which appear to correspond to the three main fault groups. For lakes fitted with multiple ellipses, the difference in means between the right-lateral, left-lateral, and thrust faults and their corresponding groups of lakes are 3.05°, 1.57°, and 5.17°. Using a Kolmogorov-Smirnov (K-S) statistical test to compare the orientations of faults with respect to the lakes suggests that there is not a strongly significant difference between the fault orientations and the corresponding lake groups. These results indicate that the faults have a profound control on the orientation, shape, and distribution of the lakes. We attribute this to faults and their damage zones being weaker and therefore prone to a faster rate of erosion, and to stress perturbations associated with discontinuous faults resulting in localized high density fracturing and surface subsidence. These results have implications for lake and drainage system morphologies in other foreland basins along the Andes and other similar settings.

  18. Developing inorganic carbon-based radiocarbon chronologies for Holocene lake sediments in arid NW China

    Zhang, Jiawu; Ma, Xueyang; Qiang, Mingrui; Huang, Xiaozhong; Li, Shuang; Guo, Xiaoyan; Henderson, Andrew C. G.; Holmes, Jonathan A.; Chen, Fahu


    Inorganic carbonates are often used to establish radiocarbon (14C) chronologies for lake sediments when terrestrial plant remains (TPR) are rare or when bulk organic matter is insufficient for dating, a problem that is common for many lakes in arid regions. However, the reservoir effect (RE), as well as old carbon contributed from the lakes catchment make it difficult to establish reliable chronologies. Here we present a systematic study of inorganic 14C ages of two lake-sediment sequences, one from a small-enclosed saline lake - Lake Gahai in Qaidam Basin, and the other from a large freshwater lake - Lake Bosten in Xinjiang. Modern dissolved inorganic carbon (DIC) of the lakes, paleo-lake sediments exposed in the catchment, and mollusk shells in core sediments from Lake Gahai were dated to assess the RE and the contribution of pre-aged carbon to the old ages in the cores. We propose a statistical regression to assess more than one RE for the 14C carbonate ages within our sedimentary sequences. Old radiocarbon ages contributed by detrital carbonates were assessed by comparing the ages of mollusk shells with those of carbonates at the same sediment depths. We established the RE of the authigenic component and assessed detrital old carbon contributions to our two sites, and this was used to correct the 14C ages. Based on this approach, we developed age models for both cores, and tested them using 210Pb ages in both cores and TPR-based 14C-ages recovered from Lake Bosten. We further tested our age models by comparing carbonate-based oxygen isotope (δ18O) records from both lakes to an independently-dated regional speleothem δ18O record. Our results suggest if sedimentary sequences are densely dated and the RE and the contribution of old carbon from detrital carbonates can be ascertained, robust chronological frameworks based on carbonate-based 14C determinations can be established.

  19. Lake Bogoria, Kenya: Hot and warm springs, geysers and Holocene stromatolites

    McCall, Joseph


    I carried out the first regional geological survey of the central Gregory Rift Valley in Kenya in 1958-60, and review here the numerous subsequent specialised studies focused on the unique endoreic Lake Bogoria (formerly Hannington), studies which embraced the sedimentology of the Holocene sediments around the lake shores, the hot-spring and geyser activities and the coring of the sediments beneath the lake. I focus on the occurrences of stromatolites in a hydrothermal environment, both in two closely spaced late Holocene (~ 4500 yr BP) generations at the lake margin, associated with algae and cyanobacteria, which represent a final more humid climatic phase after the several interglacial more humid phases (also represented by stromatolite occurrences in other rift valley lakes); and also at present being formed, at the edge of the now highly saline lake, in the very hot springs in association with thermophilic bacteria and with silica. I briefly mention the older occurrences in Lake Magadi to the south, which are quite different; and form three generations; and also present-day occurrences of stromatolites in a flood-plain environment, unlike the present-day environment at Lake Bogoria. Other stromatolite occurrences are mentioned, around Lake Turkana and the former lake in the Suguta River valley to the north. I suggest that the hot waterfall at Kapedo, at the head of the Suguta River, and the central island of Ol Kokwe (with hot springs, amidst the fresh water Lake Baringo) could well be investigated for stromatolite occurrences. Lake Bogoria, an empty wilderness occupied only by flamingos when I mapped it, is now more accessible and provides a unique open-air laboratory for such researches, but like all the Rift Valley lakes, is unique, sui generis. Results of detailed investigations of the type reviewed here, can only be applied to other occurrences of stromatolites elsewhere in the rift system or beyond the rift system with reservation.

  20. Using paleolimnology to find restoration solutions: the case of Lake Muzzano, Switzerland

    Isabelle eLarocque-Tobler


    Full Text Available Lake Muzzano (45°59′50″N 8°55′41″E, 337 m a.s.l. is a hyper-eutrophied lake located in the Tessin region of Switzerland. Almost every year, algal blooms (Microcystis cover the lake with a thickness of 1-2 cm. These blooms associated with periods of anoxia in summer have led to fish kills in 1967 and 1994. In the hope of avoiding these blooms, a bypass bringing water away from the lake has been established in 1999. This solution was not adequate as blooms kept reoccurring. Sediment removal was then proposed by the Tessin Canton as a possible remediation technique and The L.A.K.E.S Institute had a mandate in 2010 to study the lake (present and past state to determine the reasons creating anoxia and algal blooms. The present state of the lake shows that anoxia is still occurring when the algal bloom covers the lake’s surface. Subfossil diatom and chironomid analyses show that the baseline conditions were those found before 1922 AD when the lake was oligotrophic and supported a diversified community of chironomids suggesting good oxygenation. After 1922 AD, circulation to the lake was cut out and nutrients accumulated in the lake leading to anoxia and the establishment of Microcystis. Heavy metal analysis in the sediment shows that the concentration is above the national recommendation and thus sediment should not be removed or should be stored with hazardous material. Based on the present status of the lake and paleolimnological results, two solutions are proposed: to further decrease the nutrients coming in the lake (possibly using filtrating plants followed by flushing to increase lake water circulation. Physical capping of the sediment to avoid exchange of heavy metals and phosphorus release at the water/sediment interface could also be envisaged once the two prime solutions are in place.